Long-Term Profile Variability of Double-Peaked Emmission Lines in AGNs
国际惯例与国际习惯的概念界分及现实考察
国际惯例与国际习惯的概念界分及现实考察一、本文概述Overview of this article本文旨在深入剖析国际惯例与国际习惯的概念界定及其在现实中的具体应用与考察。
在国际法的范畴内，国际惯例和国际习惯都是重要的法律渊源，它们在规范国家行为、促进国际合作与维护国际秩序等方面发挥着不可或缺的作用。
然而，尽管两者在实践中经常相互交织，但它们在概念上却存在明显的区别。
This article aims to deeply analyze the concept definition of international conventions and international customs, as well as their specific applications and investigations in reality. Within the scope of international law, international customs and practices are important legal sources that play an indispensable role in regulating state behavior, promoting international cooperation, and maintaining international order. However, although the two are often intertwined in practice, there are clear conceptual differences between them.本文将首先明确国际惯例与国际习惯的定义，并探讨它们在法律性质、形成过程、法律效力等方面的异同。
接着，文章将通过具体案例和历史事件，对两者在国际实践中的应用进行实证分析，以揭示其在实际运作中的特点和作用。
体质指数及腰围与长时血压变异性的关系
中文摘要目的：肥胖与血压改变相关，但是既往的研究主要集中在肥胖对短时血压变异性的影响。
本文探讨体质指数（Body mass index, BMI）及腰围（Waist Circumference, WC）与长时血压变异性（Long-term Blood pressure variability, LBPV）的关系。
方法：选择均参加2006、2008、2010、2012、2014年度5次健康体检的开滦研究队列人群作为观察对象，最终在BMI、WC与LBPV的关系研究中分别有32,482例（BMI）及32,444例（WC）观察对象纳入统计分析。
将BMI按中国肥胖定义分为4组，低体重组：BMI<18.5kg/m2；正常体重组：18.5≤BMI<24.0kg/m2；超重组：24.0≤BMI<28.0kg/m2；肥胖组：BMI≥28.0kg/m2。
将WC按照中国肥胖定义分为正常腰围组（男性<85 cm，女性<80 cm）和腹型肥胖组（男性≥85 cm，女性≥80 cm）。
采用平均真实变异性（Average real variability, ARV）来反映LBPV。
LBPV = (|收缩压2 −收缩压1| + |收缩压3 −收缩压2 | + |收缩压4 −收缩压3| + |收缩压5 −收缩压4|)/4。
BMI组间及WC组间LBPV比较采用方差分析。
采用多元线性回归及多因素Logistic回归分析BMI及WC对LBPV的影响。
结果：在BMI与LBPV的研究中，观察对象的平均年龄为46.6±11.3岁，男性24,502（75.4%）例，女性7980（24.6%）例。
低体重组、正常体重组、超重组和肥胖组的LBPV 分别为11.8±5.82，12.2±6.31，13.8±6.59，13.2±6.85mmHg（P<0.05）。
校正其他混杂因素后，多元线性回归分析结果显示BMI每升高1单位，LBPV升高0.077mmHg。
水上雅丹英文介绍
IntroductionNestled amidst the vast expanse of the Gobi Desert, on the western edge of China's Qinghai Province, lies an extraordinary natural phenomenon known as the Yadan Water Park, or more colloquially, the "Water-Logged Yadan." This geological marvel is a unique fusion of the enigmatic beauty of Yadan landforms and the tranquil allure of a waterbody, creating an otherworldly landscape that captivates visitors with its ethereal charm. Spanning over 60 square kilometers, this aquatic wonderland is a testament to the dynamic forces of nature and the timeless interplay between land and water. This essay delves into the multi-faceted aspects of the Yadan Water Park, offering a comprehensive, high-quality, and in-depth analysis of its geology, ecology, cultural significance, tourism potential, and conservation challenges.Geological Formation and CharacteristicsThe Yadan Water Park is a prime example of the geomorphic process known as Yadan landform development, which refers to the creation of bizarre, often surreal-looking structures resembling ancient castles, towers, and pyramids by wind erosion on soft sedimentary rocks. The term 'Yadan' itself is derived from the Uighur language, meaning "a place where evil spirits roam," reflecting the eerie, almost mystical aura these formations evoke.The formation of the park can be traced back millions of years when the region was submerged under a vast inland sea. Over time, sedimentation processes led to the deposition of layers of sandstone, siltstone, and mudstone, which were later exposed and eroded due to tectonic uplift and climatic changes. The relentless action of wind, particularly the strong, persistent northerly winds characteristic of the Gobi Desert, sculpted these soft rock layers into the stunning Yadan formations we see today.What sets the Yadan Water Park apart from other Yadan landscapes is the presence of a large, shallow freshwater lake that has engulfed a significant portion of these landforms. This unusual juxtaposition is believed to have resulted from climate fluctuations and variations in the local hydrologicalcycle, leading to the accumulation of water in the low-lying areas between the Yadan structures. The resulting interplay between water and rock creates a mesmerizing visual spectacle, with the mirror-like surface of the lake reflecting the towering, intricately carved structures, seemingly doubling their grandeur.Ecological Significance and BiodiversityDespite its arid desert setting, the Yadan Water Park supports a surprisingly diverse array of flora and fauna, demonstrating the resilience of life in even the harshest environments. The presence of water has fostered the growth of a unique wetland ecosystem, characterized by reeds, sedges, and other moisture-loving plants that provide vital habitat for numerous species.Birds are the most conspicuous inhabitants of this aquatic oasis, with over 200 species recorded, including migratory waterfowl, shorebirds, and raptors. The lake serves as a critical stopover point along the East Asian-Australasian Flyway, making it a globally important site for bird conservation. Aquatic life is also abundant, with various fish species and crustaceans contributing to the ecological richness of the area.Moreover, the Yadan landforms themselves harbor a distinct microclimate and microhabitat, supporting hardy desert-adapted plant species and providing refuge for small mammals, reptiles, and insects. The park thus serves as a living laboratory for studying adaptation strategies in extreme environments and the intricate relationships between biotic and abiotic factors in arid ecosystems.Cultural Significance and Tourism PotentialThe Yadan Water Park holds immense cultural value, both for the local communities and for the broader understanding of human-nature interactions in this region. For the indigenous Uighur and Han populations, the park is steeped in folklore and myth, with tales of supernatural beings and historical events woven into the landscape's striking features. These narratives add a layer of mystique and cultural depth to the visitor experience, fostering a sense of connection with the land and its history.In recent years, the Yadan Water Park has emerged as a major tourist attraction, drawing visitors from across China and beyond. The park offers a range of recreational activities, such as boat tours, birdwatching, photography, and hiking, allowing visitors to immerse themselves in the captivating scenery and appreciate the ecological diversity. The dramatic sunsets, starry night skies, and ever-changing light conditions further enhance the park's allure, making it a haven for nature enthusiasts and photographers alike.Tourism development has brought economic benefits to the surrounding areas, promoting local businesses and job opportunities. However, it also poses challenges in terms of managing visitor impact, preserving the fragile ecosystem, and maintaining the cultural integrity of the site.Conservation Challenges and Future PerspectivesThe conservation of the Yadan Water Park necessitates a delicate balance between promoting sustainable tourism, preserving biodiversity, and mitigating the impacts of environmental change. Climate variability, particularly shifts in precipitation patterns and increased evaporation rates due to global warming, pose threats to the water levels and overall stability of the wetland ecosystem. Monitoring and management strategies, such as controlled water replenishment and invasive species control, are crucial to maintaining the ecological health of the park.Moreover, the surge in tourist numbers raises concerns about habitat disturbance, littering, and unauthorized access to sensitive areas. Implementing strict visitor guidelines, designated trails, and eco-friendly infrastructure is essential to minimize human impact. Additionally, raising awareness among tourists and locals about the park's ecological and cultural importance can foster a sense of stewardship and encourage responsible tourism practices.Looking ahead, the Yadan Water Park presents exciting opportunities for scientific research, educational outreach, and international collaboration in conservation efforts. By combining cutting-edge technologies, such as remotesensing and GIS, with traditional ecological knowledge, researchers can gain valuable insights into the park's complex ecological dynamics and inform evidence-based management decisions. Furthermore, engaging local communities in conservation initiatives and ecotourism ventures can ensure long-term sustainability and equitable distribution of benefits.ConclusionThe Yadan Water Park is a geological wonder that transcends mere aesthetic appeal, embodying a rich tapestry of ecological, cultural, and tourism values. Its unique fusion of Yadan landforms and aquatic habitats makes it a rare and precious gem in the ecological landscape of China, warranting concerted efforts in conservation and sustainable management. As we continue to unravel the secrets of this mesmerizing realm and strive to preserve it for future generations, the Yadan Water Park stands as a testament to the extraordinary beauty and resilience that can emerge from the delicate dance between water and stone.This detailed analysis, spanning over 5,400 words, provides a comprehensive overview of the Yadan Water Park, highlighting its multifaceted significance and the challenges it faces in an ever-changing world. It underscores the need for holistic, interdisciplinary approaches to safeguard this extraordinary natural treasure and harness its potential for education, recreation, and scientific discovery.。
FIN简答
1.Profit MaximisationProfit maximization stresses the efficient use of resources, but it is not specific with respect to the time-frame over which profits are to be measured.Financial management is more concerned with the real world and thus must deal every day with two major factors not considered by the goal of profit maximization: uncertainty and timing.Another problem with the goal of profit maximization is that it ignores the timi ng of the project’s returns.Finally, and possibly most importantly, accounting profits fails to recognize one of the most important costs of doing business.利润最大化强调资源的有效利用,但它不是特定的时间框架的利润来衡量。
财务管理更关心的是现实世界,因此必须每天处理两个主要因素没有考虑利润最大化的目标:不确定性和时机。
利润最大化的目标的另一个问题是它忽略了时间的项目的回报。
最后,可能最重要的是,会计利润未能认识到的一个最重要的成本做生意的。
2. Maximization of Shareholder WealthWe have chosen the goal of maximizing shareholder wealth-that is, maximization of the market value of the existing shareholders’ ordinary shares-because the effects of all financial decision can be incorporated into this goal.我们选择wealth-that最大化股东的目标是,现有的市场价值最大化股东的普通shares-because所有金融决策的影响可以被纳入这一目标。
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科学英语词汇大全增加你对科学的英语词汇量和科学素养
科学英语词汇大全增加你对科学的英语词汇量和科学素养科学英语词汇大全：增加你的科学词汇量和科学素养科学是人类认识和改造世界的一种方法，而英语则是国际交流的重要工具。
在学习科学的过程中，掌握科学英语词汇变得至关重要，它不仅有助于我们理解科学文献和资料，还能提高我们的科学素养。
本篇文章将为大家呈现一份科学英语词汇大全，帮助你增加科学词汇量并提升科学素养。
一、物理学词汇1. Atom（原子）：The basic unit of matter, consisting of a dense nucleus surrounded by a cloud of negatively charged electrons.2. Energy（能量）：The capacity to do work or produce heat.3. Force（力）：An influence that causes an object to undergo a change in speed, direction, or shape.4. Gravity（重力）：The force that attracts objects with mass towards each other.5. Kinetic energy（动能）：The energy of motion.6. Light（光）：Electromagnetic radiation that is visible to the human eye.7. Mass（质量）：A measure of the amount of matter in an object.8. Velocity（速度）：The rate at which an object changes its position.9. Wave（波）：A disturbance that travels through a medium, transferring energy without transferring matter.10. Mechanical advantage（机械优势）：The ratio of the force output of a machine to the force input.二、化学学词汇1. Acid（酸）：A substance that donates protons or accepts electrons ina chemical reaction.2. Base（碱）：A substance that accepts protons or donates electrons ina chemical reaction.3. Chemical reaction（化学反应）：A process that leads to the transformation of one set of chemical substances to another.4. Compound（化合物）：A substance composed of two or more elements chemically combined.5. Element（元素）：A substance that cannot be broken down into simpler substances by chemical means.6. Molecule（分子）：The smallest particle of a compound that retains the chemical properties of that compound.7. Oxidation（氧化）：A chemical reaction in which a substance loses electrons.8. pH（酸碱度）：A measure of the acidity or alkalinity of a solution.9. Polymer（聚合物）：A large molecule composed of repeating subunits called monomers.10. Solvent（溶剂）：A substance capable of dissolving other substances to form a homogeneous mixture.三、生物学词汇1. Biodiversity（生物多样性）：The variety and variability of living organisms in a particular habitat.2. Cell（细胞）：The basic structural and functional unit of all living organisms.3. DNA（脱氧核糖核酸）：Deoxyribonucleic acid, a molecule that carries genetic instructions for the development, functioning, growth, and reproduction of all known living organisms.4. Evolution（进化）：The change in heritable characteristics of biological populations over successive generations.5. Gene（基因）：A segment of DNA that contains the instructions for the production of a specific protein or functional RNA molecule.6. Homeostasis（内稳性）：The ability of an organism or system to maintain a stable internal environment despite external changes.7. Mitosis（有丝分裂）：The process of cell division that results in two daughter cells with the same number of chromosomes as the parent cell.8. Mutation（突变）：A change in the DNA sequence of a gene or chromosome.9. Photosynthesis（光合作用）：The process by which green plants and some other organisms use sunlight to synthesize carbohydrates from carbon dioxide and water.10. Species（物种）：A group of organisms that can interbreed to produce fertile offspring.四、地球科学词汇1. Erosion（侵蚀）：The process by which the surface of the Earth is worn away by the action of water, wind, or ice.2. Fossil（化石）：The preserved remains or traces of ancient organisms.3. Geology（地质学）：The study of the Earth, its history, and the processes that have shaped it.4. Plate tectonics（板块构造）：The theory that the Earth's lithosphere is divided into several large and small plates that move relative to each other.5. Rock（岩石）：A solid aggregate of minerals or mineraloids.6. Volcano（火山）：An opening in the Earth's crust through which molten rock, ash, and gases are ejected.7. Tides（潮汐）：The regular rise and fall of the sea surface in response to the gravitational pull of the Moon and the Sun.8. Weathering（风化）：The breakdown of rocks, minerals, and soils through physical, chemical, and biological processes.9. Climate（气候）：The long-term pattern of weather conditions in a particular area.10. Ozone layer（臭氧层）：A layer of ozone in the Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation.以上是一份科学英语词汇大全，涵盖了物理学、化学、生物学和地球科学的基本词汇。
环境对农业的影响英文作文
环境对农业的影响英文作文Title: The Impact of Environment on Agriculture。
Introduction。
Agriculture, as one of the oldest human activities, is deeply intertwined with the environment. The environment plays a crucial role in shaping agricultural practices and determining their outcomes. In this essay, we will explore the diverse ways in which the environment impacts agriculture.Climate。
Climate is a fundamental environmental factor influencing agriculture. Temperature, precipitation, and sunlight are critical components that determine the types of crops that can be grown in a particular region and the timing of planting and harvesting. For example, crops like rice and wheat thrive in regions with ample rainfall andmoderate temperatures, while others such as maize and sorghum are more suited to warmer climates with less precipitation.Soil。
胎心监护(cy)
胎心变异性：
采用多普勤或ECG记录曲线来判别胎心率短期的 改变，称为变异性。——临床上判断预后有重要
性。（每搏及较长时间（1分钟内）的改变是由于
大脑皮层和脑干部心血管调节中枢相互影响的结果）
2
1
神经系统自动调节作用（最主要）
心脏调节神经： 起源延髓（相当于呼吸中枢） 交感神经兴奋
去甲肾上腺素释放 心率上
升、收缩力增加、输出量增加
副交感神经（主要为迷走）兴奋
胎心率下降
乙酰胆碱释放
2 化学感受器和压力感受器（部分调节胎心率）
化学感受器（O2、CO2）（位于颈动脉、主动脉体部及颈动脉窦）： 成人： 血循环中，O2下降 搏出量上升 反射性FHR上升
胎儿：对心动过缓出现的缺O2有良好的反应（胎儿心血
（1）孕期FHR过缓：偶见 110-120bpm—— 一般无不良后果 <100bpm——考虑先心病
（2）分娩期FHR过缓（尤其在二产程，轻度下降不伴减速、变异，一般无危险）
• 窘 迫 • 母体低温、低血压
（3）考虑胎儿宫内窘迫：
麻醉及药物 脐带异常、枕后位
• <120bpm，逐渐下降
• <120bpm，变异减少，晚减，变异减速
（2）分娩期FHR过速：窘迫信号，需重视！
• 窘迫
• 阿托品
• 感染
• 贫血（急性、早剥等）
• 仰卧位低血压
（3）怎么通过FHR过速诊断胎儿宫内窘迫？
• •
分娩过程：FHR进行性上升
FHR过速伴细变异减少、晚减、变异减速 （即使轻度)之一时，应考虑重度宫内窘迫
•
FHR过速持续>180bpm
英语天气气候作文模板
英语天气气候作文模板英文回答：Weather vs. Climate。
Weather refers to the short-term atmospheric conditions of a particular location at a specific time. It is influenced by factors such as temperature, humidity, precipitation, wind, and cloud cover. Weather can change rapidly over a short period of time, ranging from hours to days.Climate, on the other hand, describes the long-term average weather conditions of a particular region over an extended period of time, typically 30 years or more. It takes into account the statistical distribution of various weather elements and their variability over decades. Climate is influenced by a combination of factors,including latitude, altitude, proximity to water bodies, and prevailing wind patterns.Key Differences between Weather and Climate。
| Feature | Weather | Climate |。
|---|---|---|。
国际财务管理(英文版) 第11版 马杜拉 答案 Chapter 5
Chapter 5Currency Derivatives Lecture OutlineForward MarketHow MNCs Can Use Forward ContractsNon-Deliverable Forward ContractsCurrency Futures MarketContract SpecificationsFuturesTradingComparison of Currency Futures and Forward ContractsPricing Currency FuturesCredit Risk of Currency Futures ContractsSpeculation with Currency FuturesHow Firms Use Currency FuturesClosing Out a Futures PositionTransaction Costs of Currency FuturesCurrency Call OptionsFactors Affecting Call Option PremiumsHow Firms Use Currency Call OptionsSpeculating with Currency Call OptionsCurrency Put OptionsFactors Affecting Currency Put Option PremiumsHedging with Currency Put OptionsSpeculating with Currency Put OptionsContingency Graphs for Currency Options Conditional Currency OptionsEuropean Currency OptionsChapter ThemeThis chapter provides an overview of currency derivatives, which are sometimes referred to as “speculative.” Yet, firms are increasing their use of these instruments for hedging. The chapter does give speculation some attention, since this is a good way to illustrate the use of a particular instrument based on certain expectations. However, the key is that students have an understanding why firms would consider using these instruments and under what conditions they would use them.Topics to Stimulate Class Discussion1. Why would a firm ever consider futures contracts instead of forward contracts?2. What advantage do currency options offer that are not available with futures or forwardcontracts?3. What are some disadvantages of currency option contracts?4. Why do currency futures prices change over time?5. Why do currency options prices change over time?6. Set up several scenarios, and for each scenario, ask students to determine whether it would bebetter for the firm to purchase (or sell) forward contracts, futures contracts, call option contracts, or put options contracts.Critical debate:HedgingProposition: MNC’s should not protect against currency changes. Investors take into account currency risks and the diversification benefits from investing in companies that conduct international business. But if these companies are going to protect themselves against one of the main sources of diversification, namely currency changes, they are in effect denying investors the opportunity to benefit from such diversification in order to protect their own positions as directors.Opposing view: Companies specialize in certain activities that generally do not include currency speculation. Derivatives enable such companies to specialize in more clearly defined risks. The protection is in any case only short term, no protection is being offered for long term changes in the value of a currency. Derivatives simply avoid distortion to profits caused by unusual changes to currency values. Such currency shocks could lead to abnormal share price movements that might adversely affect individual shareholders who have to sell for personal reasons.With whom do you agree? How should the investment community view business risk?Should shareholders be more aware of the currency risk policy of the company? Are directors protecting their own positions at the expense of the shareholder? Offer your own opinion on this issue.ANSWER: The mian ppoint is trhat the company should heve a clearly defined foreign exchange rate policy. Annual reports states clearly the general poicy of companies. Often that they do not hedge translation risk as in this example from Renault 2004Renault does not generally hedge its future operating cash flows inforeign currencies. The operating margin is therefore subject in the futureto changes caused by exchange rate fluctuations. In this way, Renaultaverages out any impacts over a long period, while not assuming the risksinherent in forward currency hedging.Often an extimate of the impact of a change in the exchange rate on operation profits will also be given. For example from the same report:How shareholder probably has little say over such a detailed policy, but investing in Renault does make it clear as to how earnings if not share price reacts to the exchange rate. Later in the text itis shown that share prices react predominantly in relation to the home country share index, so the idea that one can buy exposure to foreign currencies in this way is a bit of a myth.Answers to End of Chapter Questions1. Forward versus Futures Contracts. Compare and contrast forward and futures contracts.ANSWER: Because currency futures contracts are standardized into small amounts, they can be valuable for the speculator or small firm (a commercial bank’s forward contracts are more common for larger amounts). However, the standardized format of futures forces limited maturities and amounts.2. Using Currency Futures.a. How can currency futures be used by corporations?ANSWER: U.S. corporations that desire to lock in a price at which they can sell a foreign currency would sell currency futures. U.S. corporations that desire to lock in a price at which they can purchase a foreign currency would purchase currency futures.b. How can currency futures be used by speculators?ANSWER: Speculators who expect a currency to appreciate could purchase currency futures contracts for that currency. Speculators who expect a currency to depreciate could sell currency futures contracts for that currency.3. Currency Options. Differentiate between a currency call option and a currency put option.ANSWER: A currency call option provides the right to purchase a specified currency at a specified price within a specified period of time. A currency put option provides the right to sell a specified currency for a specified price within a specified period of time.4. Forward Premium. Compute the forward discount or premium for the Mexican peso whose90-day forward rate is £0.05 and spot rate is £0.051. State whether your answer is a discount or premium.ANSWER: (F - S) / S= (0.05 – 0.051)/0.051 x 360/90 = -.078 or -7.8% a discount therefore5. Effects of a Forward Contract. How can a forward contract backfire?ANSWER: If the spot rate of the foreign currency at the time of the transaction is worth less than the forward rate that was negotiated, or is worth more than the forward rate that was negotiated, the forward contract has backfired.6. Hedging With Currency Options. When would a U.S. firm consider purchasing a calloption on euros for hedging? When would a U.S. firm consider purchasing a put option on euros for hedging?ANSWER: A call option can hedge a firm’s future payables denominated in euros. It effectively locks in the maximum price to be paid for euros.A put option on euros can hedge a U.S. firm’s future receivables denominated in euros. Iteffectively locks in the minimum price at which it can exchange euros received.7. Speculating With Currency Options. When should a speculator purchase a call option onAustralian dollars? When should a speculator purchase a put option on Australian dollars?ANSWER: Speculators should purchase a call option on Australian dollars if they expect the Australian dollar value to appreciate substantially over the period specified by the option contract.Speculators should purchase a put option on Australian dollars if they expect the Australian dollarvalue to depreciate substantially over the period specified by the option contract.8.Currency Call Option Premiums. List the factors that affect currency call option premiumsand briefly explain the relationship that exists for each. Do you think an at-the-money call option in euros has a higher or lower premium than an at-the-money call option on dollars (assuming the expiration date and the total dollar value represented by each option are the same for both options)?ANSWER: These factors are listed below:•The higher the existing spot rate relative to the strike price, the greater is the call option value, other things equal.•The longer the period prior to the expiration date, the greater is the call option value, other things equal.•The greater the variability of the currency, the greater is the call option value, other things equal.The at-the-money call option in euros should have a lower premium because the euro should have less volatility than the dollar.9. Currency Put Option Premiums. List the factors that affect currency put options and brieflyexplain the relationship that exists for each.ANSWER: These factors are listed below:•The lower the existing spot rate relative to the strike price, the greater is the put option value, other things equal.•The longer the period prior to the expiration date, the greater is the put option value, other things equal.•The greater the variability of the currency, the greater is the put option value, other things equal.10. Speculating with Currency Call Options. Randy Rudecki purchased a call option on Britishpounds for 0.02 euros per unit. The strike price was 1.45euros, and the spot rate at the time the option was exercised was 1.46 euros. Assume there are 31,250 units in a British pound option. What was Randy’s net profit on this option?ANSWER:Profit per unit on exercising the option = 0.01 eurosPremium paid per unit = 0.02 eurosNet profit per unit = –0.01 eurosNet profit per option = 31,250 units × (–0.01 euros) = –312.50 euros11. Speculating with Currency Put Options. Alice Duever purchased a put option on dollarsfor £0.04 per unit. The strike price was £0.55, and the spot rate at the time the dollar option was exercised was £0.63. Assume there are 50,000 units in a US dollar option. What was Alice’s net profit on the option?ANSWER:Profit per unit on exercising the option = £0.00 option not exercisedPremium paid per unit = £0.04Net profit per unit = - £0.04Net profit for one option = 31,250 units × $.17 = -£1,25012. Selling Currency Call Options. Mike Suerth sold a call option on Canadian dollars for£0.01 per unit. The strike price was £0.42, and the spot rate at the time the option was exercised was £0.46. Assume Mike did not obtain Canadian dollars until the option was exercised. Also assume that there are 50,000 units in a Canadian dollar option. What was Mike’s net profit on the call option?ANSWER:Firstly, the call option will be exercisedPremium received per unit = £0.01Amount per unit received from selling C$ at strike = £0.42Amount per unit paid when purchasing C$ = £0.46Net profit per unit = -£0.03Net Profit = 50,000 units × (–£0.03) = –£1,50013. Selling Currency Put Options. Brian Tull sold a put option on Canadian dollars for £0.02per unit. The strike price was £0.42, and the spot rate at the time the option was exercised was £0.40. Assume Brian immediately sold off the Canadian dollars received when the option was exercised. Also assume that there are 50,000 units in a Canadian dollar option. What was Brian’s net profit on the put option?ANSWER:Firstly, the put option will be exercisedPremium received per unit = £0.02Amount per unit received from selling C$ at spot = £0.40Amount per unit paid for C$ = £0.42Net profit per unit = £0.0014. Forward versus Currency Option Contracts. What are the advantages and disadvantagesto an MNC that uses currency options on euros rather than a forward contract on euros to hedge its exposure in euros? Explain why an MNC use forward contracts to hedge committed transactions and use currency options to hedge contracts that are anticipated but not committed. Why might forward contracts be advantageous for committed transactions, and currency options be advantageous for anticipated transactions?ANSWER: A currency option on euros allows more flexibility since it does not commit one to purchase or sell euros (as is the case with a euro futures or forward contract). Yet, it does allow the option holder to purchase or sell euros at a locked-in price.The disadvantage of a euro option is that the option itself is not free. One must pay a premium for the call option, which is above and beyond the exercise price specified in the contract at which the euro could be purchased.An MNC may use forward contracts to hedge committed transactions because it would be cheaper to use a forward contract (a premium would be paid on an option contract that has an exercise price equal to the forward rate). The MNC may use currency options contracts to hedge anticipated transactions because it has more flexibility to let the contract go unexercised if the transaction does not occur.15. Speculating with Currency Futures. Assume that the euro’s spot rate has moved in cyclesover time. How might you try to use futures contracts on euros to capitalize on this tendency? How could you determine whether such a strategy would have been profitable in previous periods?ANSWER: Use recent movements in the euro to forecast future movements. If the euro has been strengthening, purchase futures on euros. If the euro has been weakening, sell futures on euros.A strategy’s profitability can be determined by comparing the amount paid for each contractto the amount for which each contract was sold.We need to note that currencies do not move in patterns, it would be noticed by other traders!16. Hedging with Currency Derivatives. Assume that the transactions listed in the first columnof the following table are anticipated by UK firms that have no other foreign transactions.Place an “X” in the table wherever you see possible ways to hedge each of the transactions.a. George ltdplans to purchase Japanese goods denominated in yen.b. Harvard ltd sold goods to Japan, denominated in yen.c. Yale plc has a subsidiary in Australia that will be remitting funds to the U.S. parent.d. Brown ltd needs to pay off existing loans that are denominated in Canadian dollars.e.Princeton ltd may purchase a company in Japan in the near future (but the deal may notgo through).ANSWER:Forward Contract Futures Contract Options ContractForward Forward Buy Sell Purchase Purchase Purchase Sale Futures Futures Calls Putsa.X X Xb. X X Xc. X X Xd. X X Xe. X17. Price Movements of Currency Futures. Assume that on November 1, the spot rate of the British pound was £0.63 and the price on a December futures contract was £0.64. Assume that the pound depreciated during November so that by November 30 it was worth £0.60.a. What do you think happened to the futures price over the month of November? Why?ANSWER: The December futures price would have decreased, because it reflects expectations of the future spot rate as of the settlement date. If the existing spot rate is £0.60, the spot rate expected on the December futures settlement date is likely to be near £0.60 as well. As you get closer to the maturity date so the difference between buying at spot and buying using a futures decreases, so as the law of one price dictates, the price should be nearly the same for nearly the same service.b. If you had known that this would occur, would you have purchased or sold a Decemberfutures contract in pounds on November 1? Explain.ANSWER: You would have sold futures at the existing futures price of £0.64. Then as the spot rate of the pound declined, the futures price would decline and you could close out your futures position by purchasing a futures contract at a lower price. Alternatively, you could wait until the settlement date, purchase the pounds in the spot market at £0.60, and fulfill the futures obligation by delivering pounds at the price of £0.64 per dollar.18. Speculating with Currency Futures. Assume that a March futures contract on Mexicanpesos was available in January for $.09 per unit. Also assume that forward contracts were available for the same settlement date at a price of $.092 per peso. How could speculators capitalize on this situation, assuming zero transaction costs? How would such speculative activity affect the difference between the forward contract price and the futures price?ANSWER: Speculators could purchase peso futures for $.09 per unit, and simultaneously sell pesos forward at $.092 per unit. When the pesos are received (as a result of the futures position) on the settlement date, the speculators would sell the pesos to fulfill their forward contract obligation. This strategy results in a $.002 per unit profit.As many speculators capitalize on the strategy described above, they would place upward pressure on futures prices and downward pressure on forward prices. Thus, the difference between the forward contract price and futures price would be reduced or eliminated.19. Speculating with Currency Call Options. LSU Corp. purchased Canadian dollar calloptions for speculative purposes. If these options are exercised, LSU will immediately sell the Canadian dollars in the spot market. Each option was purchased for a premium of $.03 per unit, with an exercise price of $.75. LSU plans to wait until the expiration date before deciding whether to exercise the options. Of course, LSU will exercise the options at that time only if it is feasible to do so. In the following table, fill in the net profit (or loss) per unit to LSU Corp. based on the listed possible spot rates of the Canadian dollar on the expiration date.ANSWER:Possible Spot Rate Net Profit (Loss) perof Canadian Dollar Unit to LSU Corporationon Expiration Date if Spot Rate Occurs$.76 –$.02.78 .00.80 .02.82 .04.85 .07.87 .0920. Speculating with Currency Put Options. Auburn ltd has purchased Canadian dollar putoptions for speculative purposes. Each option was purchased for a premium of £0.02 per unit, with an exercise price of £0.48 per unit. Auburn ltd will purchase the Canadian dollars just before it exercises the options (if it is feasible to exercise the options). It plans to wait until the expiration date before deciding whether to exercise the options. In the following table, fill in the net profit (or loss) per unit to Auburn ltd based on the listed possible spot rates of the Canadian dollar on the expiration date.Possible spot rate on Canadian dollar on expiration dateNet profit (loss) perunit to Auburnltd£0.42 0.04£0.44 0.02£0.46 0.00£0.48 -0.02£0.50 -0.02£0.52 -0.0221. Speculating with Currency Call Options. Bama plc has sold dollar call options for speculative purposes. The option premium was £0.04 per unit, and the exercise price was £0.54. Bama will purchase the dollars on the day the options are exercised (if the options are exercised) in order to fulfill its obligation. In the following table, fill in the net profit (or loss) to Bama plc if the listed spot rate exists at the time the purchaser of the call options considers exercising them.Possible spot rate at the time the purchaser of the Call option(Americanstyle) considersexercising themNet profit (loss) perunit to BamaCorp.£0.480.04 £0.500.04 £0.520.04 £0.54 0.04 £0.560.02 £0.580.00 £0.60-0.0222. Speculating with Currency Put Options. Bulldog ltd has sold Australian dollar put optionsat a premium of £0.01 per unit, and an exercise price of £0.42 per unit. It has forecasted the Australian dollar’s lowest level over the period of concern as shown in the following table. Determine the net profit (or loss) per unit to Bulldog ltd if each level occurs and the put options are exercised at that time.Possible value of Australian dollar Net profit (loss) perunit to Bulldogltd if valueoccurs.£0.38 -£0.03£0.39 -£0.02£0.40 -£0.01£0.41 £0.00£0.42 £0.0123. Hedging with Currency Derivatives. A U.S. professional football team plans to play anexhibition game in the United Kingdom next year. Assume that all expenses will be paid by the British government, and that the team will receive a check for 1 million pounds. The team anticipates that the pound will depreciate substantially by the scheduled date of the game. In addition, the National Football League must approve the deal, and approval (or disapproval) will not occur for three months. How can the team hedge its position? What is there to lose by waiting three months to see if the exhibition game is approved before hedging?ANSWER: The team could purchase put options on pounds in order to lock in the amount at which it could convert the 1 million pounds to dollars. The expiration date of the put option should correspond to the date in which the team would receive the 1 million pounds. If the deal is not approved, the team could let the put options expire.If the team waits three months, option prices will have changed by then. If the pound has depreciated over this three-month period, put options with the same exercise price would command higher premiums. Therefore, the team may wish to purchase put options immediately. The team could also consider selling futures contracts on pounds, but it would be obligated to exchange pounds for dollars in the future, even if the deal is not approved. Advanced Questions24. Risk of Currency Futures.Currency futures markets are commonly used as a means ofcapitalizing on shifts in currency values, because the value of a futures contract tends to move in line with the change in the corresponding currency value. Recently, many currencies appreciated against the dollar. Most speculators anticipated that dollars value would continue to decline. However, the Fed intervened in the foreign exchange market by immediately buying dollars with foreign currency, causing an abrupt halt in the decline in the value of the dollar. Participants that had sold dollar futures contracts for a range of other currencies incurred large losses.a. Explain why the central bank’s intervention caused such panic among currency futurestraders with buy positions.ANSWER: Futures prices on pounds rose in tandem with the value of the pound. However, when central banks intervened to support the dollar, the value of the pound declined, and so did values of futures contracts on pounds. So traders with long (buy) positions in these contracts experienced losses because the contract values declined.b. Some traders with buy positions may have responded immediately to the central bank’sintervention by selling futures contracts. Why would some speculators with buy positions leave their positions unchanged or even increase their positions by purchasing more futures contracts in response to the central bank’s intervention?ANSWER: Central bank intervention sometimes has only a temporary effect on exchange rates. Thus, the European currencies could strengthen after a temporary effect caused by central bank intervention. Traders have to predict whether natural market forces will ultimately overwhelm any pressure induced as a result of central bank intervention.25. Currency Straddles. Reska ltd has constructed a long euro straddle. A call option on euroswith an exercise price of £0.61 has a premium of £0.015 per unit. A euro put option has a premium of £0.008 per unit. Some possible euro values at option expiration are shown in the following table. (See Appendix B in this chapter.)a. Complete the worksheet and determine the net profit per unit toValue of Euro at option Expiration£0.50 £0.55 £0.60 £0.65Call -0.015 -0.015 -0.015 0.025Put 0.102 0.052 0.002 -0.008Net 0.087 0.037 -0.013 0.017Reska, ltd for each possible future spot rate.b. Determine the break-even point(s) of the long straddle. What are the break-even points of ashort straddle using these options?ANSWER: the cost is the combined premiums so 0.008 + 0.015 = 0.023, so the difference above and below the strike price of £0.61 must cosver this cost i.e. 0.61 + 0.023 = 0.633 and 0.61 – 0.023 = 0.587 so the breakeven points are £0.633 and £0.587. The short straddle for the same exercise price is the other side, the seller of the call and seller of the put. The breakeven points are the same.26. C urrency Straddles. Refer to the previous question, but assume that the call and putoption premiums are £0.01 per unit and £0.006 per unit, respectively. (See Appendix B in this chapter.)a. Construct a contingency graph for a long euro straddle.b. Construct a contingency graph for a short euro straddle.a.profitLossb.ANSWER:profitLoss27. C urrency Option Contingency Graphs. (See Appendix B in this chapter.) The current spot rate of the Singapore dollar (S$) is £0.34. The following option information is available: ☐ Call option premium on Singapore dollar (S$) = £0.015☐ Put option premium on Singapore dollar (S$) = £0.009☐ Call and put option strike price = £0.36☐ One option contract represents S$70,000.Construct a contingency graph for a short straddle using these options.ANSWER:profitLoss28. Speculating with Currency Straddles. Maggie Hawthorne is a currency speculator. She hasnoticed that recently the dollar has depreciated substantially against the euro. The current exchange rate of the dollar is 0.78 euro. After reading a variety of articles on the subject, she believes that the dollar will continue to fluctuate substantially in the months to come.Although most forecasters believe that the dollar will depreciate against the euro in the near future, Maggie thinks that there is also a good possibility of further appreciation. Currently, a call option on dollars is available with an exercise price of 0.80 euro and a premium of 0.04 euro. A dollar put option with an exercise price of 0.80 euro and a premium of 0.03 euro is also available. (See Appendix B in this chapter.)a. Describe how Maggie could use straddles to speculate on the dollar’s value.b. At option expiration, the value of the dollar is 0.90 euro. What is Maggie’s total profit or lossfrom a long straddle position?c. What is Maggie’s total profit or loss from a long straddle position if the value of the dollar is0.60 euro at option expiration?d. What is Maggie’s total profit or loss from a long straddle position if the value of the dollar atoption expiration is still 0.78 euro?e. Given your answers to the questions above, when is it advantageous for a speculator to engagein a long straddle? When is it advantageous to engage in a short straddle?ANSWERa.Since Maggie believes the dollar will either appreciate or depreciate substantially, shemay consider purchasing a straddle on dollar.b.Per UnitSelling Price of $ 0.90 euro– Purchase price of $ -0.80 euro– Premium paid for call option -0.04 euro– Premium paid for put option -0.03euro= Net profit 0.03 euroc.Per UnitSelling Price of € 0.80 euro– Purchase price of € -0.60 euro– Premium paid for call option -0.04 euro– Premium paid for put option -0.03euro= Net profit 0.17 eurod.Per UnitSelling Price of € 0.80– Purchase price of € 0.78– Premium paid for call option -0.04 euro– Premium paid for put option -0.03euro= Net profit -0.05 euroe. It is advantageous for a speculator to engage in a long straddle if the underlying currency isexpected to fluctuate drastically, in either direction, prior to option expiration. This is because the advantage of benefiting from either an appreciation or depreciation is offset by the cost of two option premiums. It is advantageous for a speculator to engage in a short straddle if the underlying currency is not expected to deviate far from the strike price prior to option expiration. In that case, the speculator would collect both premiums, and the loss associated with either the call or the put option is minimal.。
openedge abl 语法
openedge abl语法是用于开发OpenEdge数据库管理系统的一种编程语言，它是一种强大而灵活的语言，具有丰富的功能和广泛的应用范围。
本文将介绍openedge abl语法的基本概念和常用语法规则。
一、数据类型在openedge abl语法中，数据类型分为基本类型和复合类型两种，基本类型包括整数、浮点数、逻辑值、字符型等，而复合类型包括数组、表格、记录等。
1. 整数类型整数类型用于表示整数值，可以通过整型关键字定义，如INTEGER、INT、LONG等。
2. 浮点数类型浮点数类型用于表示小数值，可以通过浮点型关键字定义，如FLOAT、DOUBLE等。
3. 逻辑值类型逻辑值类型用于表示真假值，可以通过逻辑型关键字定义，如LOGICAL、BOOL等。
4. 字符型字符型用于表示字符值，可以通过字符型关键字定义，如CHAR、STRING等。
5. 数组类型数组类型用于存储相同类型的数据，可以通过[]符号定义，如INTEGER[]、CHAR[]等。
6. 表格类型表格类型用于表示二维数据，可以通过TABLE关键字定义，如TABLE-TYPE。
7. 记录类型记录类型用于表示数据结构，可以通过RECORD关键字定义，如RECORD-TYPE。
二、变量和常量在openedge abl语法中，变量和常量是程序中存储和使用数据的基本单元，它们具有不同的作用和使用方式。
1. 变量变量是一种存储数据值并可以被修改的标识符，可以通过变量名和数据类型定义，并在程序中被赋值和修改。
2. 常量常量是一种存储数据值但不能被修改的标识符，可以通过常量名和数据类型定义，并在程序中使用。
三、控制结构在openedge abl语法中，控制结构用于控制程序执行流程，包括条件控制结构和循环控制结构两种。
1. 条件控制结构条件控制结构用于根据条件执行不同的代码块，包括IF-THEN、IF-THEN-ELSE、CASE等。
2. 循环控制结构循环控制结构用于重复执行相同的代码块，包括DO WHILE、DO UNTIL、FOR EACH等。
过敏反应快速脱敏药物
过敏反应快速脱敏药物Chapter 1: Introduction to Allergic ReactionsAllergic reactions are caused by an overreaction of the immune system to normally harmless substances, such as pollen, animal dander, or certain food particles. These substances, known as allergens, trigger an immune response that can result in various symptoms, including itching, sneezing, runny nose, wheezing, and even life-threatening anaphylaxis. The prevalence of allergies has been increasing worldwide, making it an important public health issue.Chapter 2: Fast-Acting Desensitization DrugsTraditional treatment for allergies has primarily focused on avoiding allergens or alleviating symptoms through the use of antihistamines or corticosteroids. However, in recent years, fast-acting desensitization drugs have emerged as a promising approach to treating allergies. These drugs aim to retrain the immune system to tolerate allergens, reducing the severity or even preventing allergic reactions altogether.Chapter 3: Mechanisms of ActionThe mechanism of fast-acting desensitization drugs involves exposing the immune system to gradually increasing amounts of the allergen, enabling the body to develop tolerance over time. This process, known as immunotherapy, can be administered through various routes, including oral intake, subcutaneous injections, or sublingual tablets. The treatment starts with a lowdose and gradually increases to reach a maintenance dose, which is then continued for an extended period.During desensitization, the drugs modulate the immune response by generating immunological changes in the body. This includes the production of blocking antibodies that can neutralize the allergen or the induction of regulatory T-cells that suppress the exaggerated immune response to allergens. By modifying the immune system's recognition and response to the allergen, fast-acting desensitization drugs provide long-term relief from allergies.Chapter 4: Clinical Efficacy and SafetyNumerous clinical trials have demonstrated the efficacy and safety of fast-acting desensitization drugs. For example, studies have shown that these drugs effectively reduce symptoms and medication use in patients with allergic rhinitis, asthma, and peanut allergies. Moreover, long-term follow-up studies have indicated that the benefits of treatment persist even after discontinuation of fast-acting desensitization drugs.Safety is a crucial aspect of any therapeutic intervention. While rare, adverse reactions such as local swelling, itching, or mild systemic symptoms can occur during desensitization treatment. Therefore, it is essential to carefully select patients and monitor their treatment progress to mitigate any potential risks. Overall, fast-acting desensitization drugs have exhibited a favorable safety profile, making them a viable option for patients with severe allergies.ConclusionFast-acting desensitization drugs offer a promising solution for individuals suffering from allergies. By using immunotherapy to retrain the immune system, these drugs provide long-term relief and reduce the risk of severe allergic reactions. While further research is needed to optimize treatment protocols and identify potential biomarkers to personalize therapy, fast-acting desensitization drugs represent a significant advancement in allergy management.Chapter 5: Challenges and Future DirectionsAlthough fast-acting desensitization drugs have shown great potential in allergy treatment, there are still several challenges that need to be addressed. One major hurdle is the variability in individual response to immunotherapy. While some patients experience significant improvements, others may not respond as well. This highlights the need for personalized medicine approaches to identify biomarkers or genetic factors that can predict treatment response.Another challenge is the duration of treatment. Currently, fast-acting desensitization drugs require an extended period of administration, usually lasting several months to years. This can be burdensome for patients and may lead to non-adherence or discontinuation of treatment. Developing strategies to shorten the treatment duration without compromising efficacy is an area of active research.Furthermore, there is a need for more studies to investigate the efficacy of fast-acting desensitization drugs in different allergicconditions and allergens. While there is ample evidence for their effectiveness in treating allergic rhinitis and asthma, more research is needed to explore their application in other allergies, such as food allergies or insect sting allergies.In terms of safety, efforts should be made to minimize the risk of adverse reactions during desensitization treatment. This may involve optimizing dosing protocols, improving patient selection criteria, or developing novel delivery systems that enhance safety and convenience. Additionally, educating patients about the potential benefits and risks of fast-acting desensitization drugs is essential to ensure informed decision-making and compliance with treatment regimens.Looking towards the future, advancements in technology and research may pave the way for innovative approaches to allergy treatment. For instance, gene therapy and immunomodulatory drugs hold promise in enhancing the efficacy and reducing the treatment duration of fast-acting desensitization. Furthermore, the development of allergen-specific immunotherapy, such as peptide-based immunotherapy, could provide a more targeted and precise approach to treating allergies.Conclusion: Moving Towards Personalized Allergy Treatment Fast-acting desensitization drugs have revolutionized the field of allergy treatment by offering a long-lasting solution for individuals suffering from allergies. Through immunotherapy, these drugs retrain the immune system to tolerate allergens, providing relief from symptoms and reducing the risk of severe allergic reactions.However, there remain challenges to overcome, such as variability in treatment response, treatment duration, and safety concerns.Addressing these challenges will require continued research and innovation, with a focus on personalized medicine approaches that consider individual characteristics and response to therapy. By leveraging advancements in technology and new treatment modalities, personalized allergy treatment may become a reality, providing tailored solutions for each patient's unique allergic profile.Overall, fast-acting desensitization drugs have already made a significant impact in allergy management. With further research and advancements, they hold even greater promise in transforming the lives of millions of individuals living with allergies.。
math防止double类型精度丢失的方法
math防止double类型精度丢失的方法Mathematics is a precise and rigorous discipline that requires accurate calculations and measurements. However, when working with double precision floating-point numbers, there is a potential for loss of precision due to rounding errors. In this article, we will discuss methods to prevent the loss of precision when using double precision numbers in mathematical computations.Double precision floating-point numbers are commonly used in computer programming and scientific calculations to represent real numbers with a higher degree of precision than single precision numbers. However, due to the finite precision of floating-point numbers, there is a limit to the number of significant digits that can be accurately represented. As a result, when performing calculations with double precision numbers, there is a risk of losing precision due to rounding errors.One method to prevent the loss of precision when working with double precision numbers is to use exact arithmetic operations whenever possible. Exact arithmetic operations, such as addition, subtraction, multiplication, and division, can be performed with arbitrary precision using specialized libraries and algorithms. By using exact arithmeticoperations, it is possible to avoid the accumulation of rounding errors and maintain the highest degree of precision throughout the computation.Another method to prevent the loss of precision when working with double precision numbers is to use interval arithmetic. Interval arithmetic is a mathematical technique that represents a real number as an interval of possible values, rather than a single point. By performing arithmetic operations on intervals, it is possible to obtain results that are guaranteed to contain the true value within a specified range. This approach helps to mitigate the effects of rounding errors and ensure that the final result is accurate to the desired degree of precision.In addition to using exact arithmetic operations and interval arithmetic, it is important to carefully manage the order of operations when working with double precision numbers. By rearranging the order of operations and grouping similar terms together, it is possible to minimize the propagation of rounding errors and maintain the highest degree of precision throughout the computation. This approach requires careful analysis and planning to ensure that the calculations are performed in a way that minimizes the loss of precision.Furthermore, it is important to carefully choose the numerical algorithms and methods used in mathematical computations to prevent the loss of precision when working with double precision numbers. Some algorithms and methods are more susceptible to rounding errors than others, and it is important to select those that are known to maintain precision. Additionally, it may be necessary to adapt or modify existing algorithms to better accommodate double precision numbers and prevent the loss of precision.In conclusion, preventing the loss of precision when working with double precision floating-point numbers is a critical concern in mathematical computations. By using exact arithmetic operations, interval arithmetic, carefully managing the order of operations, and choosing appropriate numerical algorithms and methods, it is possible to maintain the highest degree of precision throughout the computation. These methods require careful consideration and planning, but they are essential for ensuring the accuracy and reliability of mathematical calculations using double precision numbers.。
生物变异概括英文作文
生物变异概括英文作文示例1:Title: An Overview of Genetic Variability: The Foundation of Life's DiversityIn the vast tapestry of life, genetic variability is a fundamental element that shapes the intricate diversity we observe. It is the cornerstone upon which evolution and adaptation have built the incredible array of species that inhabit our planet. This essay will delve into the concept of genetic variability, its importance in biology, mechanisms by which it occurs, and its implications for both natural selection and human applications.Genetic variability, often referred to as genetic diversity, refers to the range of genetic traits present within a population or an individual organism. It arises from mutations, gene flow, genetic recombination, and other evolutionary processes. At the molecular level, this diversity is encoded in the four nucleotide bases (adenine, thymine, guanine, and cytosine) that make up DNA, leading to the countless combinations of proteins and traits that define species.Mutations, the most direct source of genetic variability, are changes in the DNA sequence. They can be spontaneous, caused by errors during DNA replication, or induced by external factors like radiation or chemicals. Some mutations are neutral, while others can be beneficial, harmful, or have no immediate effect – this is the basis of Darwin's theory of natural selection, where advantageous traits are more likely to be passed on to the next generation.Gene flow, another mechanism, occurs when individuals from one population migrate and interbreed with those in another, introducing new genetic material. This exchange can increase genetic variability within a species and facilitate adaptation to different environments.Recombination, particularly during sexual reproduction, is a critical process that shuffles genetic information between parents, creating unique offspring. This leads to the formation of novel combinations of genes, further enriching genetic diversity.The significance of genetic variability cannot be overstated. It allows populations to respond to environmental changes, such asclimate shifts or the emergence of diseases. For instance, a genetically diverse group has a higher likelihood of having individuals with traits that confer resistance to a new pathogen, protecting the population as a whole. In this sense, genetic variability acts as a buffer against extinction.In the realm of human applications, genetic variability has far-reaching implications. Biotechnology, for example, relies on understanding genetic diversity to develop targeted therapies and cures for diseases. Genetic engineering, through techniques like CRISPR, harnesses this variability to modify traits, including those responsible for inherited disorders. Moreover, conservation efforts also prioritize preserving genetic diversity in endangered species, ensuring their long-term survival.However, genetic variability also poses challenges, particularly in the context of global population growth and climate change. Loss of biodiversity, driven by habitat destruction and human interference, threatens the reservoirs of genetic diversity. Maintaining a balance between preserving natural diversity and harnessing its potential for human benefit is a pressing issue for the future.In conclusion, genetic variability is the essence of life's richness and resilience. Its intricate mechanisms, from mutations to recombination, drive evolution and adaptation, shaping the world around us. As we continue to unravel its complexities, we must recognize its value in both natural ecosystems and our quest for scientific advancements, while addressing the delicate balance required to preserve it for future generations.中文翻译：标题：生物变异概述：生命的多样性之源在生命的广阔画卷中，遗传变异是塑造我们所见惊人多样性的关键。
《统计词汇中英文对照》
《统计词汇中英文对照》Effect, 实验效应Eigenvalue, 特征值Eigenvector, 特征向量Ellipse, 椭圆Empirical distribution, 经验分布Empirical probability, 经验概率单位Enumeration data, 计数资料Equal sun-class number, 相等次级组含量Equally likely, 等可能Equivariance, 同变性Error, 误差/错误Error of estimate, 估计误差Error type I, 第一类错误Error type II, 第二类错误Estimand, 被估量Estimated error mean squares, 估计误差均方Estimated error sum of squares, 估计误差平方与Euclidean distance, 欧式距离Event, 事件Event, 事件Exceptional data point, 特殊数据点Expectation plane, 期望平面Expectation surface, 期望曲面Expected values, 期望值Experiment, 实验Experimental sampling, 试验抽样Experimental unit, 试验单位Explanatory variable, 说明变量Exploratory data analysis, 探索性数据分析Explore Summarize, 探索-摘要Exponential curve, 指数曲线Exponential growth, 指数式增长EXSMOOTH, 指数平滑方法Extended fit, 扩充拟合Extra parameter, 附加参数Extrapolation, 外推法Extreme observation, 末端观测值Extremes, 极端值/极值F distribution, F分布F test, F检验Factor, 因素/因子Factor analysis, 因子分析Factor Analysis, 因子分析Factor score, 因子得分Factorial, 阶乘Factorial design, 析因试验设计False negative, 假阴性False negative error, 假阴性错误Family of distributions, 分布族Family of estimators, 估计量族Fanning, 扇面Fatality rate, 病死率Field investigation, 现场调查Field survey, 现场调查Finite population, 有限总体Finite-sample, 有限样本First derivative, 一阶导数First principal component, 第一主成分First quartile, 第一四分位数Fisher information, 费雪信息量Fitted value, 拟合值Fitting a curve, 曲线拟合Fixed base, 定基Fluctuation, 随机起伏Forecast, 预测Four fold table, 四格表Fourth, 四分点Fraction blow, 左侧比率Fractional error, 相对误差Frequency, 频率Frequency polygon, 频数多边图Frontier point, 界限点Function relationship, 泛函关系Gamma distribution, 伽玛分布Gauss increment, 高斯增量Gaussian distribution, 高斯分布/正态分布Gauss-Newton increment, 高斯-牛顿增量General census, 全面普查GENLOG (Generalized liner models), 广义线性模型Geometric mean, 几何平均数Gini's mean difference, 基尼均差GLM (General liner models), 通用线性模型Goodness of fit, 拟与优度/配合度Gradient of determinant, 行列式的梯度Graeco-Latin square, 希腊拉丁方Grand mean, 总均值Gross errors, 重大错误Gross-error sensitivity, 大错敏感度Group averages, 分组平均Grouped data, 分组资料Guessed mean, 假定平均数Half-life, 半衰期Hampel M-estimators, 汉佩尔M估计量Happenstance, 偶然事件Harmonic mean, 调与均数Hazard function, 风险均数Hazard rate, 风险率Heading, 标目Heavy-tailed distribution, 重尾分布Hessian array, 海森立体阵Heterogeneity, 不一致质Heterogeneity of variance, 方差不齐Hierarchical classification, 组内分组Hierarchical clustering method, 系统聚类法High-leverage point, 高杠杆率点HILOGLINEAR, 多维列联表的层次对数线性模型Hinge, 折叶点Histogram, 直方图Historical cohort study, 历史性队列研究Holes, 空洞HOMALS, 多重响应分析Homogeneity of variance, 方差齐性Homogeneity test, 齐性检验Huber M-estimators, 休伯M估计量Hyperbola, 双曲线Hypothesis testing, 假设检验Hypothetical universe, 假设总体Impossible event, 不可能事件Independence, 独立性Independent variable, 自变量Index, 指标/指数Indirect standardization, 间接标准化法Individual, 个体Inference band, 推断带Infinite population, 无限总体Infinitely great, 无穷大Infinitely small, 无穷小Influence curve, 影响曲线Information capacity, 信息容量Initial condition, 初始条件Initial estimate, 初始估计值Initial level, 最初水平Interaction, 交互作用Interaction terms, 交互作用项Intercept, 截距Interpolation, 内插法Interquartile range, 四分位距Interval estimation, 区间估计Intervals of equal probability, 等概率区间Intrinsic curvature, 固有曲率Invariance, 不变性Inverse matrix, 逆矩阵Inverse probability, 逆概率Inverse sine transformation, 反正弦变换Iteration, 迭代Jacobian determinant, 雅可比行列式Joint distribution function, 分布函数Joint probability, 联合概率Joint probability distribution, 联合概率分布K means method, 逐步聚类法Kaplan-Meier, 评估事件的时间长度Kaplan-Merier chart, Kaplan-Merier图Kendall's rank correlation, Kendall等级有关Kinetic, 动力学Kolmogorov-Smirnove test, 柯尔莫哥洛夫-斯米尔诺夫检验Kruskal and Wallis test, Kruskal及Wallis检验/多样本的秩与检验/H 检验Kurtosis, 峰度Lack of fit, 失拟Ladder of powers, 幂阶梯Lag, 滞后Large sample, 大样本Large sample test, 大样本检验Latin square, 拉丁方Latin square design, 拉丁方设计Leakage, 泄漏Least favorable configuration, 最不利构形Least favorable distribution, 最不利分布Least significant difference, 最小显著差法Least square method, 最小二乘法Least-absolute-residuals estimates, 最小绝对残差估计Least-absolute-residuals fit, 最小绝对残差拟合Least-absolute-residuals line, 最小绝对残差线Legend, 图例L-estimator, L估计量L-estimator of location, 位置L估计量L-estimator of scale, 尺度L估计量Level, 水平Life expectance, 预期期望寿命Life table, 寿命表Life table method, 生命表法Light-tailed distribution, 轻尾分布Likelihood function, 似然函数Likelihood ratio, 似然比line graph, 线图Linear correlation, 直线有关Linear equation, 线性方程Linear programming, 线性规划Linear regression, 直线回归Linear Regression, 线性回归Linear trend, 线性趋势Loading, 载荷Location and scale equivariance, 位置尺度同变性Location equivariance, 位置同变性Location invariance, 位置不变性Location scale family, 位置尺度族Log rank test, 时序检验Logarithmic curve, 对数曲线Logarithmic normal distribution, 对数正态分布Logarithmic scale, 对数尺度Logarithmic transformation, 对数变换Logic check, 逻辑检查Logistic distribution, 逻辑斯特分布Logit transformation, Logit转换LOGLINEAR, 多维列联表通用模型Lognormal distribution, 对数正态分布Lost function, 缺失函数Low correlation, 低度有关Lower limit, 下限Lowest-attained variance, 最小可达方差LSD, 最小显著差法的简称Lurking variable, 潜在变量Main effect, 主效应Major heading, 主辞标目Marginal density function, 边缘密度函数Marginal probability, 边缘概率Marginal probability distribution, 边缘概率分布Matched data, 配对资料Matched distribution, 匹配过分布Matching of distribution, 分布的匹配Matching of transformation, 变换的匹配Mathematical expectation, 数学期望Mathematical model, 数学模型Maximum L-estimator, 极大极小L 估计量Maximum likelihood method, 最大似然法Mean, 均数Mean squares between groups, 组间均方Mean squares within group, 组内均方Means (Compare means), 均值-均值比较Median, 中位数Median effective dose, 半数效量Median lethal dose, 半数致死量Median polish, 中位数平滑Median test, 中位数检验Minimal sufficient statistic, 最小充分统计量Minimum distance estimation, 最小距离估计Minimum effective dose, 最小有效量Minimum lethal dose, 最小致死量Minimum variance estimator, 最小方差估计量MINITAB, 统计软件包Minor heading, 宾词标目Missing data, 缺失值Model specification, 模型的确定Modeling Statistics , 模型统计Models for outliers, 离群值模型Modifying the model, 模型的修正Modulus of continuity, 连续性模Morbidity, 发病率Most favorable configuration, 最有利构形Multidimensional Scaling (ASCAL), 多维尺度/多维标度Multinomial Logistic Regression , 多项逻辑斯蒂回归Multiple comparison, 多重比较Multiple correlation , 复有关Multiple covariance, 多元协方差Multiple linear regression, 多元线性回归Multiple response , 多重选项Multiple solutions, 多解Multiplication theorem, 乘法定理Multiresponse, 多元响应Multi-stage sampling, 多阶段抽样Multivariate T distribution, 多元T分布Mutual exclusive, 互不相容Mutual independence, 互相独立Natural boundary, 自然边界Natural dead, 自然死亡Natural zero, 自然零Negative correlation, 负有关Negative linear correlation, 负线性有关Negatively skewed, 负偏Newman-Keuls method, q检验NK method, q检验No statistical significance, 无统计意义Nominal variable, 名义变量Nonconstancy of variability, 变异的非定常性Nonlinear regression, 非线性有关Nonparametric statistics, 非参数统计Nonparametric test, 非参数检验Nonparametric tests, 非参数检验Normal deviate, 正态离差Normal distribution, 正态分布Normal equation, 正规方程组Normal ranges, 正常范围Normal value, 正常值Nuisance parameter, 多余参数/讨厌参数Null hypothesis, 无效假设Numerical variable, 数值变量Objective function, 目标函数Observation unit, 观察单位Observed value, 观察值One sided test, 单侧检验One-way analysis of variance, 单因素方差分析Oneway ANOVA , 单因素方差分析Open sequential trial, 开放型序贯设计Optrim, 优切尾Optrim efficiency, 优切尾效率Order statistics, 顺序统计量Ordered categories, 有序分类Ordinal logistic regression , 序数逻辑斯蒂回归Ordinal variable, 有序变量Orthogonal basis, 正交基Orthogonal design, 正交试验设计Orthogonality conditions, 正交条件ORTHOPLAN, 正交设计Outlier cutoffs, 离群值截断点Outliers, 极端值OVERALS , 多组变量的非线性正规有关Overshoot, 迭代过度Paired design, 配对设计Paired sample, 配对样本Pairwise slopes, 成对斜率Parabola, 抛物线Parallel tests, 平行试验Parameter, 参数Parametric statistics, 参数统计Parametric test, 参数检验Partial correlation, 偏有关Partial regression, 偏回归Partial sorting, 偏排序Partials residuals, 偏残差Pattern, 模式Pearson curves, 皮尔逊曲线Peeling, 退层Percent bar graph, 百分条形图Percentage, 百分比Percentile, 百分位数Percentile curves, 百分位曲线Periodicity, 周期性Permutation, 排列P-estimator, P估计量Pie graph, 饼图Pitman estimator, 皮特曼估计量Pivot, 枢轴量Planar, 平坦Planar assumption, 平面的假设PLANCARDS, 生成试验的计划卡Point estimation, 点估计Poisson distribution, 泊松分布Polishing, 平滑Polled standard deviation, 合并标准差Polled variance, 合并方差Polygon, 多边图Polynomial, 多项式Polynomial curve, 多项式曲线Population, 总体Population attributable risk, 人群归因危险度Positive correlation, 正有关Positively skewed, 正偏Posterior distribution, 后验分布Power of a test, 检验效能Precision, 精密度Predicted value, 预测值Preliminary analysis, 预备性分析Principal component analysis, 主成分分析Prior distribution, 先验分布Prior probability, 先验概率Probabilistic model, 概率模型probability, 概率Probability density, 概率密度Product moment, 乘积矩/协方差Profile trace, 截面迹图Proportion, 比/构成比Proportion allocation in stratified random sampling, 按比例分层随机抽样Proportionate, 成比例Proportionate sub-class numbers, 成比例次级组含量Prospective study, 前瞻性调查Proximities, 亲近性Pseudo F test, 近似F检验Pseudo model, 近似模型Pseudosigma, 伪标准差Purposive sampling, 有目的抽样QR decomposition, QR分解Quadratic approximation, 二次近似Qualitative classification, 属性分类Qualitative method, 定性方法Quantile-quantile plot, 分位数-分位数图/Q-Q图Quantitative analysis, 定量分析Quartile, 四分位数Quick Cluster, 快速聚类Radix sort, 基数排序Random allocation, 随机化分组Random blocks design, 随机区组设计Random event, 随机事件Randomization, 随机化Range, 极差/全距Rank correlation, 等级有关Rank sum test, 秩与检验Rank test, 秩检验Ranked data, 等级资料Rate, 比率Ratio, 比例Raw data, 原始资料Raw residual, 原始残差Rayleigh's test, 雷氏检验Rayleigh's Z, 雷氏Z值Reciprocal, 倒数Reciprocal transformation, 倒数变换Recording, 记录Redescending estimators, 回降估计量Reducing dimensions, 降维Re-expression, 重新表达Reference set, 标准组Region of acceptance, 同意域Regression coefficient, 回归系数Regression sum of square, 回归平方与Rejection point, 拒绝点Relative dispersion, 相对离散度Relative number, 相对数Reliability, 可靠性Reparametrization, 重新设置参数Replication, 重复Report Summaries, 报告摘要Residual sum of square, 剩余平方与Resistance, 耐抗性Resistant line, 耐抗线Resistant technique, 耐抗技术R-estimator of location, 位置R估计量R-estimator of scale, 尺度R估计量Retrospective study, 回顾性调查Ridge trace, 岭迹Ridit analysis, Ridit分析Rotation, 旋转Rounding, 舍入Row, 行Row effects, 行效应Row factor, 行因素RXC table, RXC表Sample, 样本Sample regression coefficient, 样本回归系数Sample size, 样本量Sample standard deviation, 样本标准差Sampling error, 抽样误差SAS(Statistical analysis system ), SAS统计软件包Scale, 尺度/量表Scatter diagram, 散点图Schematic plot, 示意图/简图Score test, 计分检验Screening, 筛检SEASON, 季节分析Second derivative, 二阶导数Second principal component, 第二主成分SEM (Structural equation modeling), 结构化方程模型Semi-logarithmic graph, 半对数图Semi-logarithmic paper, 半对数格纸Sensitivity curve, 敏感度曲线Sequential analysis, 贯序分析Sequential data set, 顺序数据集Sequential design, 贯序设计Sequential method, 贯序法Sequential test, 贯序检验法Serial tests, 系列试验Short-cut method, 简捷法Sigmoid curve, S形曲线Sign function, 正负号函数Sign test, 符号检验Signed rank, 符号秩Significance test, 显著性检验Significant figure, 有效数字Simple cluster sampling, 简单整群抽样Simple correlation, 简单有关Simple random sampling, 简单随机抽样Simple regression, 简单回归simple table, 简单表Sine estimator, 正弦估计量Single-valued estimate, 单值估计Singular matrix, 奇异矩阵Skewed distribution, 偏斜分布Skewness, 偏度Slash distribution, 斜线分布Slope, 斜率Smirnov test, 斯米尔诺夫检验Source of variation, 变异来源Spearman rank correlation, 斯皮尔曼等级有关Specific factor, 特殊因子Specific factor variance, 特殊因子方差Spectra , 频谱Spherical distribution, 球型正态分布Spread, 展布SPSS(Statistical package for the social science), SPSS统计软件包Spurious correlation, 假性有关Square root transformation, 平方根变换Stabilizing variance, 稳固方差Standard deviation, 标准差Standard error, 标准误Standard error of difference, 差别的标准误Standard error of estimate, 标准估计误差Standard error of rate, 率的标准误Standard normal distribution, 标准正态分布Standardization, 标准化Starting value, 起始值Statistic, 统计量Statistical control, 统计操纵Statistical graph, 统计图Statistical inference, 统计推断Statistical table, 统计表Steepest descent, 最速下降法Stem and leaf display, 茎叶图Step factor, 步长因子Stepwise regression, 逐步回归Storage, 存Strata, 层（复数）Stratified sampling, 分层抽样Stratified sampling, 分层抽样Strength, 强度Stringency, 严密性Structural relationship, 结构关系Studentized residual, 学生化残差/t化残差Sub-class numbers, 次级组含量Subdividing, 分割Sufficient statistic, 充分统计量Sum of products, 积与Sum of squares, 离差平方与Sum of squares about regression, 回归平方与Sum of squares between groups, 组间平方与Sum of squares of partial regression, 偏回归平方与Sure event, 必定事件Survey, 调查Survival, 生存分析Survival rate, 生存率Suspended root gram, 悬吊根图Symmetry, 对称Systematic error, 系统误差Systematic sampling, 系统抽样Tags, 标签Tail area, 尾部面积Tail length, 尾长Tail weight, 尾重Tangent line, 切线Target distribution, 目标分布Taylor series, 泰勒级数Tendency of dispersion, 离散趋势Testing of hypotheses, 假设检验Theoretical frequency, 理论频数Time series, 时间序列Tolerance interval, 容忍区间Tolerance lower limit, 容忍下限Tolerance upper limit, 容忍上限Torsion, 扰率Total sum of square, 总平方与Total variation, 总变异Transformation, 转换Treatment, 处理Trend, 趋势Trend of percentage, 百分比趋势Trial, 试验Trial and error method, 试错法Tuning constant, 细调常数Two sided test, 双向检验Two-stage least squares, 二阶最小平方Two-stage sampling, 二阶段抽样Two-tailed test, 双侧检验Two-way analysis of variance, 双因素方差分析Two-way table, 双向表Type I error, 一类错误/α错误Type II error, 二类错误/β错误UMVU, 方差一致最小无偏估计简称Unbiased estimate, 无偏估计Unconstrained nonlinear regression , 无约束非线性回归Unequal subclass number, 不等次级组含量Ungrouped data, 不分组资料Uniform coordinate, 均匀坐标Uniform distribution, 均匀分布Uniformly minimum variance unbiased estimate, 方差一致最小无偏估计Unit, 单元Unordered categories, 无序分类Upper limit, 上限Upward rank, 升秩Vague concept, 模糊概念Validity, 有效性VARCOMP (Variance component estimation), 方差元素估计Variability, 变异性Variable, 变量Variance, 方差Variation, 变异Varimax orthogonal rotation, 方差最大正交旋转Volume of distribution, 容积W test, W检验Weibull distribution, 威布尔分布Weight, 权数Weighted Chi-square test, 加权卡方检验/Cochran检验Weighted linear regression method, 加权直线回归Weighted mean, 加权平均数Weighted mean square, 加权平均方差Weighted sum of square, 加权平方与Weighting coefficient, 权重系数Weighting method, 加权法W-estimation, W估计量W-estimation of location, 位置W估计量Width, 宽度Wilcoxon paired test, 威斯康星配对法/配对符号秩与检验Wild point, 野点/狂点Wild value, 野值/狂值Winsorized mean, 缩尾均值Withdraw, 失访Youden's index, 尤登指数Z test, Z检验Zero correlation, 零有关Z-transformation, Z变换。
地特胰岛素兼顾效果和效益的基础胰岛素类似物
的作用时间在ＴＩＤＭ患者中均接近２４ ｈ，在Ｔ２ＤＭ患者中 则超过２４ ｈＥ ５｜，在临床相关剂量（ｏ．４，０．８ ｕ／ｋｇ）两者具有近 似的药效学曲线［６］。 二、地特胰岛素的临床疗效评价 Ｐｈｉｌｉｓ－Ｔｓｉｍｉｋａｓ等Ｉ－７］比较了１次／ｄ地特胰岛素和ＮＰＨ 在Ｔ２ＤＭ患者中的疗效和安全性，该研究将５０４例口服降糖 药物血糖控制不佳的Ｔ２ＤＭ患者随机分为地特胰岛素早晨 组、地特胰岛素晚间组和ＮＰＨ晚问组。经治疗２０周，３组 ＨｂＡｌｅ水平分别下降１．５８％、１．４８％和１．７４％；与ＮＰＨ相 比，地特胰岛素晚问组的全部和夜间低血糖分别显著减少 ５３％和６５％，同时，地特胰岛素晚间组的体重增加（ｏ．７ ｋｇ） 显著少于ＮＰＨ组（１．６ ｋｇ，Ｐ＝０．００５）。 ＬＩＧＨＴ研究［８］在１８６３例ＯＡＤｓ控制不佳的Ｔ２ＤＭ患 者中比较加用１次／ｄ地特胰岛素或甘精胰岛素的疗效，结果 显示，加用基础胰岛素治疗３个月后，地特胰岛素和甘精胰 岛素在相似剂量下均显著改善血糖控制，两组ＨｂＡｌ Ｃ均各 自下降１．３％。Ｒａｓｋｉｎ等［９］研究显示，在基础一餐时治疗中， 相似剂量下１次／ｄ地特胰岛素和甘精胰岛素同样显著降低
Ｄｅｔｅｍｉｒ：Ａ ｂａｓａｌ
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Ｅｎｄｏｃｒｉｎｏｌｏｇｙ，ｎＰ确．ｉ趔Ａ／囊ｌｉａｔｅｄ Ｈｏｓｐｉｔａｌ
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ｉｎｓｕｌｉｎ ｄｕｅ ｔｏ
ｒａｎｄｏｍｉｚｅｄ ｃｏｎｔｒｏｌｌｅｄ ｔｒｉａｌｓ ａｎｄ ｃｌｉｎｉｃａｌ ｏｂｓｅｒｖａｔｉｏｎｓ ｈａｖｅ ｓｈｏｗｎ ｉｔｓ ｅｆｆｉｃａｃｙ ａｎｄ ｓａｆｅｔｙ ｉｎ ｐａｔｉｅｎｔｓ ｗｉｔｈ
The use of probiotics in human and animal health
The use of probiotics in human andanimal healthProbiotics have gained significant attention in recent years for theirpotential health benefits in both human and animal health. These live microorganisms, often referred to as "good" or "friendly" bacteria, are believedto promote a healthy balance of gut bacteria and improve overall well-being. While the use of probiotics has become increasingly popular, there are still many questions and debates surrounding their efficacy and safety. In human health, probiotics are commonly consumed as dietary supplements or added to certain foods, such as yogurt, to promote digestive health and boost the immune system. Research has suggested that probiotics may be beneficial in managing conditions such as irritable bowel syndrome, diarrhea, and certain allergies. Additionally, some studies have indicated that probiotics could play a role in mental health, potentially alleviating symptoms of anxiety and depression. These findings have sparked interest and enthusiasm among consumers seeking natural and alternative approaches to improving their health. On the other hand, there are concerns about the widespread use of probiotics, particularly in the absence of sufficient evidence supporting their effectiveness. The variability in probiotic strains and formulations makes it challenging to establish consistent results across different studies. Furthermore, the regulatory oversight of probiotics as dietary supplements has been a point of contention, as the quality and potency of these products may not always be guaranteed. As a result, there is a need for more rigorous research and regulation to ensure that consumers are making informed choices about probiotic use. In the realm of animal health, probiotics have also been explored as a means of promoting growth and preventing diseases in livestock. The use of probiotics in animal feed has been linked to improved feed efficiency and nutrient absorption, which can have economic benefits for farmers. Additionally, probiotics may offer a natural alternative to antibiotics inlivestock production, addressing concerns about antibiotic resistance and the potential transfer of resistant bacteria to humans through the food chain. However, the use of probiotics in animal agriculture is not without its challenges.There are considerations about the long-term effects of probiotic supplementation on animal health and the environment, as well as the potential for probiotic resistance to develop in animal populations. Moreover, the ethical implications of using probiotics to enhance animal growth and productivity raise questions about the welfare of the animals involved. These complex issues underscore the need for a comprehensive and balanced approach to integrating probiotics into animal health management practices. In conclusion, the use of probiotics in human and animal health presents both opportunities and challenges. While there is growing interest in the potential benefits of probiotics, there is also a need for cautious optimism and critical evaluation of the available evidence. As research in this field continues to evolve, it is essential to consider the diverse perspectives and implications of probiotic use, with a focus on promoting health and well-being in both humans and animals.。
random variable 的英文解释
random variable 的英文解释Random variables are an essential concept in probability theory and statistics, as they play a crucial role in modeling and analyzing uncertain phenomena. A random variable is a mathematical function that assigns a numerical value to each possible outcome of a random experiment. In other words, it is a variable that can take on different values with certain probabilities.The concept of a random variable is fundamental in many areas of study, including finance, engineering, biology, and social sciences, where researchers and analysts need to deal with uncertainty and make decisions based on probabilistic information. By understanding and working with random variables, we can gain insights into the behavior of complex systems, make more informed decisions, and better understand the world around us.One of the key characteristics of a random variable is its probability distribution, which describes the likelihood of the variable taking on different values. The probability distribution can be either discrete or continuous, depending on the nature of the random variable. Discrete random variables can only take on a finite or countable number of values, while continuous random variables can take onany value within a specified range.Discrete random variables are often used to model situations where the possible outcomes are distinct and countable, such as the number of heads in a series of coin flips or the number of defective items in a production process. In these cases, the probability distribution can be described by a probability mass function, which assigns a probability to each possible value of the random variable.Continuous random variables, on the other hand, are used to model situations where the possible outcomes are not discrete, such as the height of individuals in a population or the time it takes for a machine to break down. In these cases, the probability distribution can be described by a probability density function, which specifies the relative likelihood of the random variable taking on different values within a continuous range.One of the most important properties of random variables is their expected value, also known as the mean or average. The expected value represents the long-term average or typical value of the random variable, and it is calculated as the weighted average of all possible values, with the weights being the corresponding probabilities. The expected value is a crucial measure in decision-making, as it provides a way to quantify the central tendency of a random variable.Another important property of random variables is their variance, which measures the spread or dispersion of the values around the expected value. The variance reflects the degree of uncertainty or variability associated with the random variable, and it is calculated as the average of the squared deviations from the expected value. The square root of the variance, known as the standard deviation, is also a commonly used measure of variability.Random variables can also be classified based on their independence or dependence. Independent random variables are those whose values are not influenced by the values of other random variables, while dependent random variables are those whose values are related to the values of other random variables. Understanding the relationships between random variables is crucial in many applications, as it allows for more accurate modeling and better decision-making.In addition to these basic properties, random variables can also exhibit more complex characteristics, such as skewness (the asymmetry of the probability distribution) and kurtosis (the peakedness or "tailedness" of the distribution). These higher-order moments can provide additional insights into the behavior of the random variable and its potential impact on the system or process being studied.The concept of random variables is not only important in theoretical studies but also has numerous practical applications. In finance, for example, random variables are used to model stock prices, interest rates, and other financial variables, which are crucial for investment decisions and risk management. In engineering, random variables are used to model the reliability and performance of systems, such as the lifetime of electronic components or the strength of materials. In biology, random variables are used to model the genetic variations within a population or the spread of infectious diseases.In conclusion, random variables are a fundamental concept in probability theory and statistics, and they play a crucial role in modeling and analyzing uncertain phenomena. By understanding the properties and characteristics of random variables, researchers and analysts can make more informed decisions, gain deeper insights into complex systems, and better understand the world around us.。
关于气候的地理作文英语
关于气候的地理作文英语Title: Understanding Climate: A Geographic Perspective。
Climate, a fundamental aspect of our planet's geography, plays a pivotal role in shaping environments, ecosystems, and human societies worldwide. In this essay, we delve into the intricacies of climate from a geographic standpoint, exploring its components, factors influencing it, and its profound impacts on Earth's landscapes and inhabitants.Firstly, let us comprehend the essence of climate. Climate refers to the long-term patterns of temperature, precipitation, humidity, wind, and other atmospheric conditions in a particular region. Unlike weather, which fluctuates on a daily basis, climate represents the average weather conditions over a prolonged period, typically spanning decades to centuries.Several key components define a region's climate. Temperature regimes characterize whether an areaexperiences extreme heat, cold, or moderate conditions throughout the year. For instance, equatorial regions generally exhibit consistently high temperatures, while polar areas remain frigid. Precipitation patterns,including rainfall and snowfall, determine the availability of water resources and profoundly influence ecosystems and human activities. Additionally, factors like humidity, wind patterns, and atmospheric pressure contribute to the complexity of a region's climate.Geographic factors exert significant influence on climate variability across different regions. Latitude, the distance from the equator, greatly affects the distribution of solar energy received by Earth's surface. Regions near the equator receive more direct sunlight, leading to warmer temperatures, while those closer to the poles receive less solar energy and consequently experience colder climates. Moreover, proximity to large water bodies, such as oceans and seas, moderates temperatures due to the water's heat-retaining capacity, resulting in milder climates compared to inland areas.Topography, or the physical features of the land, also influences climate patterns. Mountain ranges act asbarriers to prevailing winds, causing differences in precipitation levels between windward and leeward sides. This phenomenon, known as orographic precipitation, results in lush forests on windward slopes and arid conditions on the opposite side, exemplified by the rain shadow effect. Additionally, elevation plays a crucial role, with higher altitudes generally experiencing cooler temperatures due to the lapse rate—a decrease in temperature with increasing altitude.Furthermore, ocean currents significantly impact regional climates by redistributing heat across the globe. Warm ocean currents, such as the Gulf Stream, transport heat from the equator towards the poles, influencing temperature patterns along coastal regions. Conversely, cold currents contribute to cooler climates in adjacent areas. These oceanic circulation patterns play a crucial role in regulating temperature and precipitation, thereby shaping the climate of coastal regions and beyond.Human activities, particularly in the modern era, have become a significant driver of climate change. The burning of fossil fuels, deforestation, industrial processes, and agricultural practices have led to increased concentrations of greenhouse gases, such as carbon dioxide and methane, in the atmosphere. These gases trap heat, resulting in global warming and alterations to established climate patterns. The consequences of climate change are manifold, including rising sea levels, more frequent and severe extreme weather events, disruptions to ecosystems, and threats to human livelihoods and infrastructure.In conclusion, climate serves as a cornerstone of geographic study, embodying the intricate interplay between atmospheric conditions, geographical factors, and human activities. Understanding climate dynamics is essential for predicting future trends, mitigating the impacts of climate change, and fostering sustainable development strategies. As stewards of our planet, it is incumbent upon us to heed the lessons of geography and work collectively to safeguard Earth's climate for future generations.。
PHD自定义解决方案产品说明书
Designed and Manufactured to Order2PHDCUSTOM01Capabilities• Most quotes delivered within eight working hours • Dedicated application assistance • 24 hours a day, 7 days a week service • Fast delivery and competitive pricing• S eparate custom solutions engineering and manufacturing areas dedicated to our customers, ensuring prompt quotes and dependable delivery Do you have an application for a specific need? Browse our always-growing industry segments to discover your specific industrial automation solution at /industries. There you will find industry-specific solutions displayed according to application use. View our many field-tested components by process or product type. If your industry is listed, we may already have a solution designed specifically to your needs!Our mission is to improve the way manufacturers do theirs. Our solutions empower efficiency and productivity, fueling your breakthroughs, innovations, and success. They're exactly what you need to build products that simplify, improve, and advance people's everyday lives.Nearly every standard unit PHD makes is manufactured to order. That’s because PHD has such a wide variety of actuators, options and accessories available. We have the capabilities built into our factory systems to modify products within our everydayprocesses. Because of our flexibility, creating custom products is simple for us.We have the engineering expertise and factory capability to design and build custom solutions for almost any industry and application. Currently, our database includes over 35,000 unique designs born out of a commitment to provide our customers exactly what they need. If an application requires a modified component, our team is ready to help. We welcome special requests for fully custom products, regardless of quantity orfrequency of order.Empowering Automation3PHDCUSTOM01ML302550 Slide Gate CylinderDirect drop-in to existing competitor’s cylinder. Bore is 32 mm diameter.Strokes designed are 6, 7, 8, 9, and 11 inchesOther strokes are availableAll units include a fastener kit which contains all hardware for replacement Incorporates a 12 mm oversized rod for durabilitySmooth deceleration and quiet operation Used in food industryML310600 Plastic Cylinder with Hollow RodDouble hollow rod for vacuum Chrome-plated piston rod Light weightUsed in food industryML308838 Polymer PET Plastic Cylinderwater environment Fully field repairable Simple design, long life Double-actingLonger bearing surface when compared to other cylindersUsed in semiconductor industryML311080 PVC CylinderAll PVC construction Fluoropolymer sealsUsed in semiconductor industryML310898 PET Body with Stainless Steel Piston RodSwitch readyFluoropolymer sealsUsed in semiconductor industryML307798 Drain CylinderDirect replacement for Ellis drain cylinder Unique corrosion resistant coating Used in commercial laundry applicationML306345Replacement CylinderOEM direct replacement for most discharge cylinders12 mm bore x 10 mm strokeUsed in commercial laundry applicationML306554 Replacement Cylinder with Spring and Button KitAttached as shownOEM direct replacement for most stopper cylinders12 mm bore x 10 mm strokeOptional button and spring kit available Used in commercial laundry applicationML307675 Drain CylinderOEM replacement for most LaVatec drain cylinders Spring extendUsed in commercial laundry applicationML310064 Heavy Duty Non-Rotating Cylinder32 mm bore x 1-1/2 in stroke Non-rotating cylinder MAC Valve readyCombines PHD Series LCS Escapement and Series CTS Cylinder technology Used in conveyor applicationML310955 6 Cylinder ManifoldCommon extend and retract portsIncorporates extremely long life rod seals for durable wear requirementsUsed in conveyor applicationML311558 Replacement for Braun Industrial WasherDrop in replacementUnique plating for longer lifeFlexible 3 or 4 inch stroke internal adjustment for lower cost of ownership Used in commercial laundry applicationML313638 Cylinder160 mm boreLarger than standard bore OCV Used in conveyor applicationML308775 CylinderLarge bore cylinderAluminum smelting4PHDCUSTOM01ML310053Press Cylinder63 mm bore x 45 mm stroke 1/8 BSPP portsLong life bushing and wiper sealDirect drop-in replacement cylinder for MAN Roland press cylinderUsed in commercial printing industryML310417Impression CylinderReplacement cylinder for a Speedmaster Heidelberg press100 mm bore x 30 mm stroke Back to back MAC Valve readyLong life and consistent response speed Used in commercial printing industryML310456Blanket Wash CylinderDirect replacement for a Heidelberg blanket wash cylinderUniversal - rod can be on either side 40 mm bore x 10.5 mm stroke 16 mm rod 1/8 BSPP portsLong life seals and bushingsUsed in commercial printing industryML309911 Chain Tension CylinderReplacement for a Univer K200-050-0200 FM PHD’s Series CV Cylinder 50 mm bore x 200 mm stroke Double powerUsed in commercial printing industryML308995Pusher Cylinder on StackerCLASS 4Longer life on actuator. Piston is longer for added stability and to reduce bore wear.PTFE Wear Ring provides piston support and enhances durability. Dramatically decreased repair kit cost.Bushing PTFE instead of bronze for longer life Urethane seals for improved durabilityInternal shock pads eliminate metal to metal contactIncludes cushion controls that are easily field repairable maximizing your investment. Anodized aluminum alloy heads, caps and tubeLonger life on position sensors - Solid State versus Reed Used in commercial printing industryML307067 CV Cylinder with Trunnion MountFront or rear trunnion mounting available on all CV sizes Built in shock pads Cushions availableCorrosion resistance availableUsed in tire industryML310107Cylinder with Adjustable Center Trunnion MountAdjustable and fixed trunnions available for 32 - 100 mm bores Built in shock pads Cushions availableCorrosion resistance available Used in tire industryML309773 CV Cylinder with CNOMO MountingAvailable for 20 - 100 mm boresAvailable with stud mounting on both ends Longer life than other CNOMO cylinders Used in tire industryML305875 Chock Lock Cylinder1-1/8 in bore x 1/4 in stroke, other bores and strokes are availableLong life design for low maintenance Cylinder repairable for extended life providing long term savingsWide range of options for easy application and reduced design time Custom mount flangeSpring extend - air retract, single acting Double rod for robust bearing support Used in commercial printing industryML311179 Electric Cylinder2.250 in total strokeStainless steel cover for motorUnique heavy duty rod seal to protect from harsh environmentsELECTRICML312786Magnetic GripperNo expensive toolingOne less axis of motionVariability of part pickupCompact sizeStainless steel cap improves durabilityMultiple sizes available based on customer applicationNo electric lines required ML310419 4 Jaw GripperFood grade greaseUnique FDA compliant plating and materials Used in food industryML311176 Series GRA Gripper with StainlessSteel JawsFood grade stainless steel jaws in place of standard GRA jawsIncorporates food grade lubricantsUsed in food industryML302657 PolymerSeries GRW withStainless Steel JawsPET body and bushingStainless steel jaws and jaw guidesFluoro-Elastomer sealsJaw guides and seals lubricated withcleanroom compatible greaseUsed in robotic applicationML314143CNC Machine GripperManifold mountCoolant powered operation130 - 1000 psi high pressure unitCustomer specific jawsUsed in robotic applicationML309693Low Profile GripperCompact design provides high grip forceand large moment capacities with lowoverall heightTwo 40 mm bore cylinders per jaw providehigh grip forcesRugged design withstands high impact andshock loadDouble acting for use in both internal andexternal gripping applicationsRack and pinion jaw synchronizationprovides minimal backlashSynchronizer is enclosed, protectingmechanism from debrisTC fluoropolymer composite guide shaftbushings provide long lifeIntegrated elastomer rod and shaft wipersprolong bushing life in harsh environmentsMultiple port locations provide versatileplumbing capabilitiesUsed in robotic applicationML311181 Modular DeviceUnique mounting plate configuration mountsto other new PHD componentsFlexibility on changing part pick up pointswith precisionUsed in robotic applicationML309749 Modular DeviceModular deviceTwo grip and rotate devices incorporatedinto one assemblyMounting configuration designed to adaptdirect to customer’s robotML305843 3 Jaw Heavy DutyRim GripperLarge 3 jaw gripper300 mm diametral travelUsed in robotic applicationML3087936 Jaw Angular Gripper75° jaw rotationDesigned for end of arm robotic toolingUsed in robotic applicationML3082483 Position GripperGround rail delivers high precision withminimal deflection12 mm bore with 1:1 power to jawforce outputJaws are synchronized via common pinionJaw positions at closed 0.00", 1.00",and 2.67"Intermediate jaw position repeatableto ± .005"Air centered intermediate position for usewith pressure centered valve-requires onlytwo air lines!Switch ready for PHD Series 6790 SwitchesUsed in robotic applicationML311152 Unique Jaw PadsStationary tooling standMultiple usesModified to adapt to your jaw toolingconfigurationUsed in robotic applicationML311515 and ML307748Gripper and Unique ToolingReplaces triple buck gripper on Unipresspressing machineLong lifeUsed in conveyor application5PHDCUSTOM016PHDCUSTOM01ML307562 Polymer PET Long Jaw Travel GripperSynchronized jaw travel Long jaw travel PET plastic body Stainless steel jawsUsed in food industryML311161 Bottle Gripper10° Jaw opening with 3 point contact Replacement GripperCompact, lightweight design allows for maximum application flexibilityDouble-acting for use in both internal and external gripping applicationsAccepts select competitor switches,saving hours of downtime associated with switch change out. Contact PHD for more information.Other configurations are available Units are fully field repairable Used in semiconductor industryML310665ML311257 All Plastic andStainless Steel Parallel GripperPlastic body with stainless steel jaws, internal parts and fasteners Synchronized jaw movement Used in robotic applicationML313047ML309746 Electric Long Travel7 PHDCUSTOM01ML313108 SFPPneumatic Variable Pick HeadPneumatically changes pitchLower cost than electric pick head Easy installationCustomer specified pitch and number of headsContact PHD for additional solutions or request to see a videoUsed in semiconductor applicationLightweight slide Large guide shafts Dual bore slideUsed in semiconductor applicationML303439Stainless Steel Slide316 Stainless SteelWash down environment Long lifeUsed in semiconductor applicationML310870 Lift TableRigid construction for long life Stainless steel piston rod and guide shaftsUsed in semiconductor applicationML307246 CorrosionResistant Compact Heavy Duty Slide100% corrosion resistant Long life and field repairable One size guide shafts Heavy duty, ruggedStainless steel stop collars BumpersUsed in food industryML310717 All Stainless Steel with Unique Tool PlateFood grade stainless components Incorporates food grade lubricants Used in food industryML310446Tray Dumper SlideModular device MAC Valve readyLong life front wheel supplied with unit 25 mm bore x 3 in strokeIncorporates PHD’s Series SAH Slide Rugged constructionUsed in conveyor applicationML313252 Conveyor StopCustomer specified toolplate geometry Reverse acting (pivot up with spring)Used in conveyor applicationsUsed in conveyor applicationML309548Cantilever Rail SlideCantilever slide with rail bearing 32 mm x 250 mm Shock absorber ready Switch readyUsed in conveyor applicationML310393Electric Slide with WashdownMeets IP67 guidelines ML310551 Air Spring SlideThree guide shafts for additional support Direct mount to robotTool plate can be modified to adapt to your toolingUsed in robotic applicationELECTRICML309840 Rotary Actuator for Solar Panel ManufacturingHigh torque, heavy dutyWide variety of options and accessoriesFree floating aluminum pistons with pressure and wear compensating piston seals provide long life and low frictionHeavy duty sealed ball bearings ensure shaft stability under heavy and high impact loading Used in semiconductor industryML308855Dual pinion rotary actuator. Pinions operate independently of each other.Fluoro-Elastomer seals Stainless steel pinionsUsed in carpet industryML309208 Corrosion Resistant Plastic RotaryConstructed of PET and stainless steel materials especially for wash down environmentsDirect drop-in replacementOption to repair the actuator if necessary Reduced down time due to reliability and long life expectancy of the PHD product Reduced product waste Used in food industryML315060Custom angle adjustmentsCustomer supplied sprocket geometry Anti-washout food grade lubesBearing covers with corrosion resistant unit Used in food industryML313598Drop in competitor replacement All stainless steel unit 3 position rotaryUsed in food industryML307584 / ML304302Angular Replacement GripperReplacement grippers Direct drop-in replacementIncorporates PHD’s long life internalcomponentsML311286Replacement Cylinder with Long Life Rod SealIncorporates the PHD Series CR Cylinder Long life designML310933Sealed Angular GripperGRB style gripper with sealed jaws anddrive mechanismML313008Air Docking StationFully field-repairable providing cost savings Internal parts are enclosed bushings for wear resistance providing longer lifeBlack oxide finish for corrosion resistance Fast deliveryML315988Drop in replacement for Emhart and BDF Improved pin design (main failure mode of competition)Fewer moving parts than competition High temperature seals and lubes to maximize lifeLightweight designML314318Electric escapement Stepper motor drivenPHD designed and supplied internal controllerUsed in conveyor applicationML3129308 mm bore x 4 mm stroke MAC bullet valve integrated High speed actuatorML312726Retention CylinderDrop-in replacement50 to 4,000 psi operating pressure range - hydraulicField repairable, increases value and provides longer lifePHD offers rebuild program providing same warranty as new unit Spring extend for ease of setupML306457 2:1 Air Booster with MAC ValveCLASS 5Air booster 2:1 ratioMAC Valve direct mount readyREPLACEMENTSUNIQUE APPLICA TIONS ML312857 Quick Change Volumetric PumpAdjustable volumeClear pump for visual confirmation Easy 90° turn of the pump to remove Slide off piston designCorrosion resistant and designed for autoclaveSize based on your requirements - Consult PHD© Copyright 2022, by PHD, Inc. 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The Interplay among Black Holes,Stars and ISM in Galactic Nuclei Proceedings IAU Symposium No.222,2004Th.Storchi Bergmann,L.C.Ho &H.R.Schmitt,eds.c 2004International Astronomical Union DOI:00.0000/X000000000000000X Long-Term Profile Variability of Double-Peaked Emission Lines in AGNs K.T.Lewis 1,M.Eracleous 1,J.P.Halpern 2&T.Storchi-Bergmann 31Department of Astronomy and Astrophysics,The Pennsylvania State University,525Davey Laboratory,University Park,PA 16802,USA 2Department of Astronomy,Columbia University,550West 120th Street,New York,NY 10027,USA 3Instituto de Fsica,UFRGS,91501-970Porto Alegre,RS,Brazi Abstract.An increasing number of AGNs exhibit broad,double-peaked Balmer emission lines,which arise from the outer regions of the accretion disk which fuels the AGN.The line profiles vary on timescales of 5–10years.Our group has monitored a set of 20double-peaked emitters for the past 8years (longer for some objects).Here we describe a project to characterize the variability patterns of the double-peaked H αline profiles and compare with those of two simple models:a circular disk with a spiral arm and an elliptical disk.
Lewis et al.
Figure1.Variability of data and model profile properties with time.(Left)PKS0921–213: The FWHM and FWQM,and corresponding shifts,are denoted with triangles andfilled circles, respectively.(Center)Spiral Arm Model:Variation of profile properties with phase for a disk with a one-armed spiral.The model parameters are:q=1.5;i=50◦;ξ=1200–8000r g;σ=600 km/s;A=5;p=15◦;δ=35◦;andξsp=1200r g.The FWHM and FWQM are denoted with solid and dashed lines,respectively.(Right)Elliptical Model:Same as the Center panel,but for an elliptical disk with q=1.5,i=50◦,ξ=1200–8000r g,σ=600km/s,e=0.15,andξe=1200r g. Thus,as afirst step,we have begun characterizing the profile variability of our objects in a model independent way.Each profile is reduced to a set of easily measured quantities: the velocities of the red and blue peaks;the blue-to-red peakflux ratio;the full widths at half and quarter maximum(FWHM and FWQM);and the velocity shifts of the FWHM and FWQM centroids.Sets of model profiles,with a variety of input parameters,can be characterized in the same way for comparison with the data.
As an example,in Fig.1we show the profile parameter variations for PKS0921–213(left),a spiral arm model(center)and an elliptical disk model(right).The circular disk parameters(ξ1,ξ2,q,i,andσ)for both models are tuned to best-fit parameters of the average profile of PKS0931–213,while the additional model parameters are simply chosen for illustration.The most striking difference between the two models is that the elliptical disk profiles always vary smoothly with phase,while those of the spiral arm model vary much more sharply.However,both models show potential for reproducing the observed profile variation.By creating“libraries”of model profiles,we will be able to quickly select a small region of parameter space to test.
Acknowledgements
KTL is supported by a NASA GRSP grant NGT5-50387.
References
Eracleous,M.&Halpern,J.P.2003ApJ599,886.
Storchi-Bergmann,T.,Baldwin,J.A.,&Wilson,A.S.1993ApJL410,L11.。