Magnon Broadening Effects in Double Layered Manganite La_1.2 Sr_1.8 Mn_2 O_7
23699772_那米鸡早期生长发育规律研究
DOI: 10.12101/j.issn.1004-390X(n).201907029那米鸡早期生长发育规律研究*胡 瑀1,2， 邓 俊3， 邱立华1， 范新阳1， 黄 静1， 王荣平2 **， 苗永旺1 **(1. 云南农业大学 动物科学技术学院，云南 昆明 650201；2. 云南农业职业技术学院 畜牧兽医学院，云南 昆明 650212；3. 云南省畜牧总站，云南 昆明 650224)摘要: 【目的】研究那米鸡的生长发育规律。
【方法】选用 Gompertz 、Logistic 和 Von Bertalanffy 3 种常用的非线性曲线模型对那米鸡0~210日龄体质量进行了生长曲线拟合与分析。
【结果】那米鸡体质量的累积生长曲线呈现“S”形，表明其生长发育正常；表现为60日龄之前生长速度较慢，60~120日龄阶段为该鸡的生长旺盛期，120日龄以后生长速度逐渐减缓。
60日龄以前，公鸡、母鸡的体质量累积生长曲线基本一致，60日龄以后，公鸡生长速度明显快于母鸡。
3种曲线模型均能较好的拟合公、母鸡的生长发育，拟合度均达0.99以上，其中Gompertz 模型对公鸡的拟合值与实际值最为接近，Von Bertalanffy 模型对母鸡的拟合值与实际值最接近，表明Gompertz 模型对那米鸡公鸡体质量的拟合度更高(R 2=0.998)，Von Bertalanffy 模型对母鸡体质量的拟合度更高(R 2=1.000)。
【结论】本研究揭示了那米鸡的生长发育规律，表明运用Gompertz 和Von Bertalan-ffy 模型对那米鸡进行生长曲线的拟合与分析是可行的，可为那米鸡的饲养管理及选育利用提供依据。
关键词: 那米鸡；生长发育；生长曲线；拟合度中图分类号: S 831.4 文献标志码: A 文章编号: 1004–390X (2021) 02−0229−06Study on the Characteristics of the Early Growth andDevelopment of Nami ChickenHU Yu 1,2，DENG Jun 3，QIU Lihua 1，FAN Xinyang 1，HUANG Jing 1，WANG Rongping 2，MIAO Yongwang 1(1. Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, China;2. Department of Animal Husbandry & Veterinary medicine, Yunnan Agricultural College of Vocational Education, Kunming 650212, China; 3. Yunnan Animal Husbandry Station, Kunming 650224, China)Abstract: ［Purposes ］In order to study the growth and development characteristics of Nami chick-en.［Methods ］Three nonlinear curve model commonly used Gompertz, Logistic and Von Bertalan-ffy, were used to fit and analyze the weight of Nami chicken at the age of 0-210 days.［Results ］The cumulative growth curve of Nami chicken showed “S” shape, indicating that its growth and develop-ment was normal. This curve showed that the growth rate was slow before 60 days of age, and fast at the age of 60 to 120 days, and slowed down gradually after 120 days of age. Before 60 days old, the accumulative growth weight of cocks and hens was basically the same, and after 60 days old, the云南农业大学学报（自然科学），2021，36(2)：229−234Journal of Yunnan Agricultural University (Natural Science)E-mail:********************收稿日期：2019-07-13 修回日期：2020-11-13 网络首发时间：2021-03-10 17:10:04*基金项目：迪庆州科技局项目(KX141626)；国家自然科学基金项目(31760659)。
Comparative physiological, metabolomic, and transcriptomic improved abiotic by exogenous melatonin
Journal of Experimental Botany, Vol. 66, No. 3 pp. 681–694, 2015doi:10.1093/jxb/eru373 Advance Access publication 15 September, 2014This paper is available online free of all access charges (see /open_access.html for further details)ReseaRch PaPeRComparative physiological, metabolomic, and transcriptomic analyses reveal mechanisms of improved abiotic stress resistance in bermudagrass [Cynodon dactylon (L). Pers.] by exogenous melatoninHaitao Shi1,*, Chuan Jiang2,3,*, Tiantian Ye1,3, Dun-Xian Tan4, Russel J. Reiter4, Heng Zhang2,†, Renyi Liu2,† and Zhulong Chan1,†1 Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China2 Shanghai Center for Plant Stress Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 201602, China3 University of Chinese Academy of Sciences, Beijing, 100039, China4 Department of Cellular and Structural Biology, The University of Texas Health Science Center, San Antonio, TX, USA*These authors contributed equally to this work.† To whom correspondence should be addressed. E-mail: zhulongch@ or ryliu@ or hengzhang@ Received 22 July 2014; Revised 12 August 2014; Accepted 13 August 2014AbstractMelatonin (N-acetyl-5-methoxytryptamine), a well-known animal hormone, is also involved in plant development and abiotic stress responses. In this study, it is shown that exogenous application of melatonin conferred improved salt, drought, and cold stress resistances in bermudagrass. Moreover, exogenous melatonin treatment alleviated reactive oxygen species (ROS) burst and cell damage induced by abiotic stress; this involved activation of several antioxi-dants. Additionally, melatonin-pre-treated plants exhibited higher concentrations of 54 metabolites, including amino acids, organic acids, sugars, and sugar alcohols, than non-treated plants under abiotic stress conditions. Genome-wide transcriptomic profiling identified 3933 transcripts (2361 up-regulated and 1572 down-regulated) that were dif-ferentially expressed in melatonin-treated plants versus controls. Pathway and gene ontology (GO) term enrichment analyses revealed that genes involved in nitrogen metabolism, major carbohydrate metabolism, tricarboxylic acid (TCA)/org transformation, transport, hormone metabolism, metal handling, redox, and secondary metabolism were over-represented after melatonin pre-treatment. Taken together, this study provides the first evidence of the protec-tive roles of exogenous melatonin in the bermudagrass response to abiotic stresses, partially via activation of anti-oxidants and modulation of metabolic homeostasis. Notably, metabolic and transcriptomic analyses showed that the underlying mechanisms of melatonin could involve major reorientation of photorespiratory and carbohydrate and nitrogen metabolism.Key words:Abiotic stress, antioxidant, bermudagrass, melatonin, metabolites, reactive oxygen species, transcriptomic. IntroductionMelatonin (N-acetyl-5-methoxytryptamine) is a well-known animal hormone that is involved in many biological processes including sleep, mood, circadian rhythms, retinal physiology, seasonal reproductive physiology, temperature homeostasis, sexual behaviour, antioxidative activity, and immunological enhancement (Galano et al., 2011; Venegas et al., 2012; Calvo© The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (/licenses/by/3.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.682 | Shi et alet al., 2013). However, melatonin is not only found exclusively in animals, but is ubiquitously present in almost all forms of life including protists, prokaryotes, eukaryotic unicells, algae, fungi, and plants (Dubbels et al., 1995; Hattori et al., 1995; Kolář and Macháčkova, 2005; Arnao and Hernández-Ruiz, 2006, 2007; Tan et al., 2007a, b, 2012).In 1995, two reports first identified melatonin in higher plants (Dubbels et al., 1995; Hattori et al., 1995). In the last 20 years, additional research found that melatonin is univer-sally distributed in leaves, roots, stems, fruits, and seeds of all plant species examined (Manchester et al., 2000; Reiter et al., 2001; Kolář and Macháčkova, 2005; Hernández-Ruiz and Arnao, 2008; Murch et al., 2009; Zhao et al., 2013). Interestingly, remarkably high concentrations of melatonin have been identified and quantified in popular beverages (beer, tea, coffee, and wine), crops (barley, corn, grape, wheat, rice, tobacco, and oats), and Arabidopsis in comparison with those in animals (Manchester et al., 2000; Kolář and Macháčkova, 2005; Arnao and Hernández-Ruiz, 2006, 2009b, 2013a, b; Tan et al., 2007a, 2012; Ramakrishna et al., 2012). Additionally, the melatonin content of tomato and rice has been modified by genetic engineering (Okazaki and Ezura, 2009; Okazaki et al., 2009, 2010; Byeon et al., 2012, 2013, 2014; Byeon and Back, 2014a, b). The well-known beneficial effects of mela-tonin on human health and the abundance of melatonin in popular beverages and crops may encourage the daily con-sumption of these products (Tan et al., 2012).To date, melatonin has also been found to be a ubiqui-tous modulator in multiple plant developmental processes and various stress responses (Kolář and Macháčkova, 2005; Arnao and Hernández-Ruiz, 2006; Tan et al., 2007a, 2012). Changes in melatonin in plants may be involved in circadian rhythms, flowering, promotion of photosynthesis, preserva-tion of chlorophyll (Arnao and Hernández-Ruiz, 2009a; Tan et al., 2012), stimulation and regeneration of root system architecture (Hernández-Ruiz et al., 2005; Pelagio-Flores et al., 2012; Zhang et al., 2014), delayed senescence of leaves (Byeon et al., 2012; Wang et al., 2012, 2013a, b), and allevia-tion of oxidative damage mediated by reactive oxygen species (ROS) and reactive nitrogen species (RNS) burst (Tan et al., 2012) Moreover, melatonin protects against multiple abiotic processes such as cold stress (Posmyk et al., 2009a; Kang et al., 2010; Bajwa et al., 2014), copper stress (Posmyk et al., 2008, 2009b), high temperature (Byeon and Back 2014b), salt stress (Li et al., 2012), osmotic stress (Zhang et al., 2013), drought stress (Wang et al., 2014), and pathogen infection (Yin et al., 2013). The mechanisms were partially character-ized after the direct exogenous application of melatonin to plants (Posmyk et al., 2008, 2009a, b; Zhao et al., 2011; Li et al., 2012; Pelagio-Flores et al., 2012; Wang et al., 2012, 2013a, b; Yin et al., 2013; Bajwa et al., 2014) or the creation of transgenic plants that produced either more or less mela-tonin through modulating its metabolic pathway (Kang et al., 2010; Byeon et al., 2013, 2014; Park et al., 2013; Byeon and Back, 2014a; Wang et al., 2014). Finally, the recent studies which showed the protective roles of melatonin in response to abiotic stress indicate that this indole might be a poten-tially ideal target for future genetic engineering technology to improve abiotic stress resistance in plants. Thus, transgenic plants with higher melatonin concentration might lead to breakthroughs to improve crop production in agriculture as well as the general health of humans (Tan et al., 2012). Bermudagrass [Cynodon dactylon (L). Pers.] is a warm-season turfgrass for lawns, parks, and sport fields cultivated worldwide (Shi et al., 2012, 2013a, b, 2014b, c, d). In response to global changed environmental stresses, improvement of abiotic stress resistance is very important for grass engineer-ing (Shi et al., 2012, 2013a, b, 2014b, c, d). As mentioned above, melatonin might be an ideal target for future genetic engineering of some plant species. However, the endogenous melatonin concentration and the possible role of mela-tonin in response to abiotic stress in bermudagrass is largely unknown. In this study, endogenous melatonin was examined after abiotic stress treatments in bermudagrass plants, and exogenous melatonin treatment was applied to investigate the in vivo role of melatonin in the response of bermudagrass to abiotic stress. In addition, the effects of exogenous mela-tonin treatment on ROS accumulation and cell damage, as well as underlying antioxidant responses, were determined. Moreover, comparative metabolomic and transcriptomic analyses were performed to identify differentially expressed metabolites and genes after exogenous melatonin treatment. This study provided some insights into the physiological and molecular mechanisms of melatonin in bermudagrass responses to multiple abiotic stresses.Materials and methodsPlant materials and growth conditionsNewly harvested common bermudagrass seeds were used in this study. After stratification in deionized water at 4 °C for 4 d in dark-ness, the bermudagrass seeds were sown in soil in the growth room, which was controlled at 28 °C, with an irradiance of ~150 μmol quanta m–2 s–1, 16 h light and 8 h dark cycles, and ~65% relative humidity.Plant abiotic stress treatmentTo test the effect of exogenous melatonin on plant physiological responses and abiotic stress resistance, 21-day-old bermudagrass plants were irrigated with water or with different concentrations of melatonin solutions for 7 d, respectively. After melatonin pre-treatment, all control and melatonin-pre-treated 28-day-old bermu-dagrass plants were subjected to subsequent salt, drought, or cold stress treatments. For salt stress treatment, 28-day-old bermudagrass plants were irrigated with NaCl solutions for 25 d; the NaCl concen-tration was increased stepwise by 50 mM every 5 d to a final concen-tration of 300 mM. For drought stress treatment, 28-day-old plants were subjected to a drought condition by withholding water for 21 d and then re-watered for 4 d. For cold stress treatment, 28-day-old bermudagrass plants were subjected to 4 °C treatment for 21 d, and then transferred to –10 °C for 8 h. The freezing stress-treated plants were then recovered overnight at 4 °C and transferred to a standard growth room (28 °C) for 4 d. In each independent experiment, three pots with ~40 plants in each pot were used for each treatment in one concentration of melatonin, and at least three independent experi-ments were performed to obtain the results.The survival rate of the salt-, drought-, or freezing-stressed plants was recorded at 25 d after stress treatments. The plant leaf samples from melatonin-pre-treated 28-day-old plants were collected at theMelatonin-mediated abiotic stress responses in bermudagrass | 683indicated time points after salt, drought, or cold treatment for the assays of multiple of physiological parameters.Quantification of melatonin by enzyme-linked immunosorbent assay (ELISA)Melatonin from plant leaves was extracted using the acetone–methanol method as described by Pape and Lüning (2006). Briefly, 1 g of plant leaf samples was ground in liquid nitrogen, and then transferred to 5 ml of extraction mixture (acetone:methanol:wa ter=89:10:1) and homogenized extensively on ice, and the homogen-ate was centrifuged at 4500 g for 5 min at 4 °C. The supernatant was moved to a new centrifuge tube containing 0.5 ml of 1% trichloric acid for protein precipitation. After centrifugation at 12 000 g for 10 min at 4 °C, the extract was used for quantification of melatonin using the Melatonin ELISA Kit (EK-DSM; Buhlmann Laboratories AG, Schonenbuch, Switzerland) according to the manufacturer’s instruction as described in Shi and Chan (2014a).Quantifications of chlorophyll contentPlant leaf chlorophyll was extracted using 80% (v/v) acetone for 6 h with shaking in the dark. The concentration of chlorophyll was then calculated by examining the absorbance at 645 nm and 663 nm of the centrifuged supernatant.Quantification of electrolyte leakage (EL)The EL of plant leaves under control and abiotic stress conditions was assayed using a conductivity meter (Leici-DDS-307A, Shanghai, China) as previously described (Shi et al., 2012, 2013a, b, 2014b, c, d). The relative EL was expressed as the ratio of initial conductivity to the conductivity after boiling.Determination of malondialdehyde (MDA) contentThe MDA content was extracted using chilled thiobarbituric acid (TBA) reagent, and was quantified via determining the absorbance of the supernatant at 450, 532, and 600 nm as previously described (Shi et al., 2012, 2013a, b, 2014b, d).Determination of ROS accumulation and antioxidantsAs two major indicators of ROS accumulation, hydrogen peroxide (H2O2) and superoxide radical (O2·–) contents were quantified using the titanium sulphate method and the Plant O2·– ELISA Kit (10-40-488, Bejing Dingguo, Beijing, China) as previously described (Shi et al., 2012, 2013a, b, 2014b, d).The activities of three antioxidant enzymes, namely superoxide dismutase (SOD; EC 1.15.1.1), catalase (CAT; EC 1.11.1.6). and peroxidase (POD; EC 1.11.1.7), were assayed using a Total SOD Assay Kit (S0102; Haimen Beyotime, Haimen city, China), a CAT Assay Kit (S0051; Haimen Beyotime), and a Plant POD Assay Kit (A084-3; Nanjing Jiancheng, Nanjing city, China), respectively, as described by Shi et al., 2012, 2013a, b, 2014b, d). The concen-trations of reduced glutathione (G SH) and oxidized glutathione (G SSG) were determined using the G SH and G SSG Assay Kit (S0053; Haimen Beyotime) as described by Shi et al. (2014b, d), and the GSH redox state was calculated as the ratio of GSH concentra-tion to the concentration of GSH plus GSSG.Extraction, identification, and quantification of metabolites Extraction, identification, and quantification of metabolites from plant leaves were performed as in Shi et al. (2014d). Briefly, the metabolite extraction and sample derivatization were performed as in Lisec et al. (2006), then the derivatizated extract was injected into a DB-5MS capillary cloumn (30 m×0.25 mm×0.25 μm; Agilent J&W GC column, California, USA) using gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) (Agilent 7890A/5975C) according to the protocol described by Shi et al. (2014d). After the GC-TOF-MS assay, the various metabolites were identified via com-paring every retention time index-specific mass with reference spec-tra in mass spectral libraries (NIST 2005, Wiley 7.0). The numerous metabolites were then quantified based on the pre-added internal standard (ribitol) in the process of metabolite extraction.Hierarchical cluster analysisThe hierarchical cluster analysis of several metabolites was per-formed using the CLUSTER program (http://bonsai.ims.u-tokyo. ac.jp/~mdehoon/software/cluster/) and Java Treeview (http:// /) as in Shi et al., 2012, 2013a, b, 2014b, d). For cluster analysis, all metabolites were quantified as fold change relative to the wild-type bermudagrass plants under control condi-tions, which was set as 1.0.RNA extraction, library construction, and sequencingFor RNA extraction, 28-day-old bermuagrass plants in pots that were irrigated with water or 20 μM melatonin for 7 d were used. Each treatment was represented by two replicate leaf samples, and each sample contained leaves from at least 30 seedlings. Total RNA was extracted with TRIzol (Invitrogen) and was quantified as pre-viously described (Shi et al., 2013c). RNA quality was determined using a 2100 Bioanalyzer (Agilent Technologies, Santa Clara, CA, USA) according to the manufacturer’s protocol. The cDNA librar-ies were constructed with the mRNA-Seq Sample Preparation Kit™ (Illumina, San Diego, CA, USA) and the DNA yield and fragment insert size distribution of each library were determined on the Agilent Bioanalyzer. The cDNA libraries were then sequenced on an Illumina HiSeq2500 sequencing instrument using the 100 bp sin-gle end protocol.Quantitative real-time PCRThe above RNA samples were also used for synthesis of first-strand cDNA with reverse transcriptase (BIO-RAD, Hercules, CA, USA), and the cDNAs were used for quantitative real-time PCR using a CFX96™ Real Time System (BIO-RAD) as previously described (Shi et al., 2013c). The specific primers of the analysed genes for real-time PCR are listed in Supplementary Table S1 available at JXB online, and the housekeeping genes have been described in Hu et al. (2012).Bioinformatics analyses of RNA-Seq dataRaw RNA-Seq reads were first trimmed for low quality regions using clean reads with length longer than 25 bp, obtained after trim-ming low quality bases (Q<17) using the SolexQA tool (v2.2) and removing adaptor sequences using the cutadapt tool (v1.3) (Martin, 2011). A total of 679 million clean RNA-Seq reads from 20 librar-ies, and four libraries were used for transcriptome profiling in this study. Transcriptome analyses of RNA-Seq data were used for transcriptome assembly using Trinity software (v r20131110) (Haas et al., 2013). The resulting pre-assembled transcriptome were refined according to the methods described by Ranjan et al. (2014). After transcripts expressed at a low level and redundant sequences were removed, 28 456 high quality transcripts were retained as the final reference transcriptome for bermudagrass.To obtain putative annotations, the final transcriptome sequences were compared with the NCBI nr protein database by BlastX using an E-value of 1e-5 as the cut-off. Blast2GO (v 2.5.0) (Gotz et al., 2008) was used to assign G O terms to each tran-script. The final transcriptome sequences were also compared with Arabidopsis (TAIR10) and rice (MSU release7) protein database using BlastX with an E-value cut-off of 1e-5. The best hit from these two well-annotated species was used to annotate each ber-mudagrass transcript.684 | Shi et alTo evaluate the abundance of each transcript, reads from indi-vidual libraries were mapped to the final reference transcripts using Bowtie, and the read counts on each transcript were estimated by the software RSEM with default parameters (Li and Dewey, 2011). Differentially expressed transcripts were identified by the R package edge R (Robinson et al., 2010.).GO term enrichment analysis of differentially expressed genes was carried out using the topGO Bioconductor package (v 2.16.0) (Alexa et al., 2006) for up- and down-regulated genes, respectively. The Classification SuperViewer T ool (http://bar.utoronto.ca/ntools/cgi-bin/ ntools_classification_superviewer.cgi) was used to generate an overview of the enriched pathways (Provart and Zhu, 2003), and MapMan was used as the classification source to assign functional pathways for each gene (Thimm et al., 2004; Y ang et al., 2013). The normalized frequency (NF) of each functional category was calculated as described in Chan et al. (2011): NF=sample frequency of each category in this experiment/ background frequency of each category in the Arabidopsis genome.Statistical analysisThe experiments in this study were repeated three times and the data shown are the means ±SEs. The means are the average of three inde-pendent experiments. Each independent experiment was a pooled sample from at least 30 bermudagrass plants. Bars with different let-ters above the columns in the figures indicate significant differences at P<0.05 (Duncan’s range test).ResultsAbiotic stress induced the endogenous melatonin levelin bermudagrassTo investigate how abiotic stress affected the melatonin con-tent, endogenous melatonin levels in bermudagrass leaves were quantified after treatments with 300 mM NaCl, drought, or cold (4 °C) stresses for 0, 7, 14, and 21 d. Melatonin con-tent remained steady at ~50 pg g–1 fresh weight (FW) in non-treated control plants (Fig. 1). After abiotic stress treatments, the melatonin content in bermudagrass leaves significantly increased (Fig. 1). The induction of melatonin content by multiple abiotic stress treatments indicated the in vivo role of melatonin in bermudagrass response to abiotic stress.Exogenous melatonin improved abiotic stress resistance in bermudagrassAfter 7 d pre-treatment with different concentrations of mela-tonin (0, 4, 20, and 100 μM melatonin, respectively), no sig-nificant differences were observed between non-treated and melatonin pre-treated plants (28 d old) (Fig. 2A). When salt, drought, or cold (4 °C) stresses were applied, the endogenous melatonin levels were activated, and 20 μM and 100 μM mel-atonin-pre-treated bermudagrass had significantly higher lev-els than non-melatonin-treated plants (Fig. 2B). G rowth and physiological parameters including chlorophyll, EL, survival rate, plant height, and plant biomass (weight) of melatonin-pre-treated 28-day-old bermudagrass plants were generally equivalent to those of non-treated plants under well-watered conditions for the following 25 d (Fig. 2C–G). After salt, drought, or freezing stress treatments, growth of both melatonin-pre-treated and non-treated plants was inhibited, but 20 μM and 100 μM melatonin-pre-treated plants had greener leaf tissues than those of non-treated bermudagrass plants (Fig. 2A). Consistently, 20 μM or 100 μM melatonin-pre-treated plants exhibited a significantly higher chlorophyll content, lower EL, and higher survival rate than did non-treated bermudagrass plants (Fig. 2C–E). Moreover, 20 μM and 100 μM melatonin-pre-treated plants exhibited healthy growth in comparison with non-treated and 4 μM melatonin-pre-treated plants, with sig-nificantly higher plant height and weight (Fig. 2F, G). These results indicate that exogenous melatonin application improved salt, drought, and freezing stress resistance in bermudagrass.Exogenous melatonin alleviated abiotic stress-induced ROS accumulation in bermudagrassAs the major indicators of the stress-triggered ROS level and oxidative damage, H2O2, O2·–, and MDA contents were assayed among control and 20 μM melatonin-pre-treated plants during abiotic stress treatments. Under control con-ditions, melatonin had no significant effect on H2O2, O2·–, and MDA contents (Fig. 3A–C). When salt, drought, and cold (4 °C) stresses were applied, melatonin-pre-treated plants showed significantly lower levels of H2O2, O2·–, and MDA in comparison with non-treated bermudagrass plants, conferring less oxidative damage (Fig. 3A–C). These results indicated that exogenous application of melatonin could modulate abiotic stress-triggered ROS accumulation and related oxidative damage in bermudagrass.Effects of exogenous melatonin on ROS-related antioxidants in bermudagrass response toabiotic stressTo alleviate abiotic stress-triggered ROS burst, plants have developed complex antioxidant defence system, including several antioxidant enzymes and non-enzymatic glutathione antioxidant pool. Under control conditions, no significant differences in antioxidant enzymes and the non-enzymatic glutathione antioxidant pool were found between non-treated and melatonin-pre-treated bermudagrass (Fig. 4A–F). Under abiotic stress conditions, the activities of antioxidant enzymes (SOD, CAT, and POD) and the GSSG content were greatly induced, while G SH content was significantly decreased (Fig. 4A–F). Additionally, melatonin-pre-treated plants Fig. 1. The endogenous melatonin level was induced by salt, drought, and cold stresses in bermudagrass. T wenty-eight-day-old bermudagrass plants were treated with control, 300 mM NaCl, drought, and cold (4 °C) stresses for 0, 7, 14, and 21 d, respectively. Bars with different letters above the columns of figures indicate significant differences at P<0.05 (Duncan’s range test).Melatonin-mediated abiotic stress responses in bermudagrass | 685showed significantly higher activities of antioxidant enzymes (SOD, CAT, and POD) and a higher GSH redox state in com-parison with non-treated plants, conferring more effective antioxidants (Fig. 4A –F ). These results indicated that mela-tonin had significant effects on both antioxidant enzymes and the non-enzymatic glutathione antioxidant pool, which might be consistent with alleviated abiotic stress-induced ROS accu-mulation and related oxidative damage in bermudagrass.Modulation of metabolic homeostasis by exogenousmelatonin treatment under control and abiotic stressconditionsTo gain more insights into the modulation of metabolic homeostasis by exogenous melatonin treatment under control and abiotic stress conditions, G C-TOF-MS was performed to identify differentially expressed metabolites. In total, 54 metabolites, comprising 16 amino acids, 13 organic acids, 18 sugars, five sugar alcohols, and two aromatic amines, were reproducibly examined in non-treated and melatonin-pre-treated plants under control and abiotic stress conditions (Fig. 5; Supplementary Table S2 at JXB online). Under con-trol conditions, no significant regular pattern of these metab-olites was shown in non-treated and melatonin-pre-treated plants (Fig. 5; Supplementary Table S2). When salt, drought,and cold (4 °C) stresses were applied, melatonin-pre-treatedplants exhibited higher concentrations of almost all the 54metabolites than non-treated plants (Fig. 5; SupplementaryTable S2). Additionally, many of these metabolites were com-monly regulated by salt, drought, and cold (4°C) stressesFig. 2. Application of exogenous melatonin improved abiotic stress resistance in bermudagrass. (A) Growth of 28-day-old plants with different melatonin treatments and under control, salt, drought, or freezing stress conditions. The picture is representative of one pot for every treatment in one concentration of melatonin, and at least nine pots with ~120 lines were used for the stress treatments with similar results. (B) Melatonin content of 28-day-old plants with different melatonin treatments and under control, 300 mM NaCl, drought stress, and cold (4 °C) stress conditions for 14 d. (C, D) Chlorophyll (C) and EL (D) of 28-day-old plants with different treatments (0, 4, 20, and 100 μM melatonin, respectively) under control, 300 mM NaCl, drought stress, and freezing stress conditions for 21 d. (E) The survival rate of bermudagrass plants after 25 d of treatments of control, 300 mM NaCl, re-watered from drought, and freezing stresses. (F , G) Plant height (F) and fresh weight (G) of bermudagrass plants after 24 d of treatments of control, 300 mM NaCl, re-watered from drought, and freezing stresses. The results shown are the means ±SE (n =3 for B, n =4 for C–E, and n =12 for F and G), and bars with different letters above the columns of figures indicate significant differences at P <0.05 (Duncan’s range test). (This figure is available in colour at JXB online.)686 | Shi et al(Fig. 5; Supplementary Table S2). Interestingly, 18 metabo-lites, comprising 10 amino acids, six sugars, and two sugar alcohols, were assigned to the carbon metabolic pathway comprising glycolysis, oxidative pentose phosphate pathway, and the tricarboxylic acid (TCA) cycle, indicating the direct link between melatonin and the carbon metabolic pathway in bermudagrass response to abiotic stress. Melatonin-pre-treated plants exhibited significantly higher levels of thesemetabolites than non-treated plants under abiotic stress con-ditions (Fig. 6A ).Transcriptome analysis: GO annotation and enrichmentanalysisSince melatonin pre-treatment increased salt, drought, and freezing stress resistance in bermudagrass, the 28-day-old plants (without and with 7 d of pre-treatment) were used for transcriptomic analysis to reveal the effect of melatonin pre-treatment on global transcriptional reprogramming. Approximately 679 million RNA-Seq reads were used for de novo assembly of the bermudagrass transcriptome. After removing poorly expressed and redundant transcripts, 28 456 high quality transcripts were retained as the final refer-ence transcriptome. These annotated transcripts were used to search various protein databases. In total, 22 137 (78%) had BLASTX hits in the well-annotated Arabidopsis and/or rice protein database (E-value >1e-5). G O annotation was performed using the Blast2G O pipeline, and 18 701 (66%) transcripts were assigned with at least one GO term. Among the three GO categories, 13 402 transcripts were annotated in Biological Process, 14 052 transcripts in Molecular Function, and 14 685 in Cellular Component.Using fold change >2 and false discovery rate (FDR) <0.05 as thresholds, 3933 transcripts (2361 up-regulated and 1572 down-regulated by exogenous melatonin treatment) were identified as differentially expressed genes (Supplementary Tables S4, S5 at JXB online). Many stress-responsive genes were highly induced by exogenous melatonin treatment in bermudagrass (Table 1). Interestingly, several C-REPEAT-BINDING FACTORS/DEHYDRATION-responsive ELEMENT-BINDING PROTEIN (CBF/DREB ) genes and target genes, heat shock transcription factors (TFs), zinc fin-ger TFs, WRKY , MYB , bHLH genes, and hormone-related genes were highly induced >16-fold after melatonin treatment (Table 2). GO enrichment analysis in the biological process domain suggested that genes related to the cysteine biosyn-thetic process, response to light signal, and the photosyn-thetic process were down-regulated. In particular, the studies of Wang et al. (2012) showed that melatonin can lower ROS damage of many photosynthetic components. Therefore, the expression of genes involved in the photosystem might been suppressed through a negative feedback mechanism. The up-regulated genes were greatly enriched with the GO terms involved in gene expression regulatory process, such as pro-tein phosphorylation, DNA-dependent transcription, regula-tion of circadian rhythm, etc. (Fig. 7).To confirm the reliability of the RNA-Seq data, the expres-sion of 18 genes (nine up-regulated and nine down-regulated by exogenous melatonin treatment) that were differentially expressed between control and melatonin-treated plants was assessed via quantitative real-time PCR. Consistently, the results of the real-time PCR assay exhibited the same trend and were correlated with the RNA-Seq data (Supplementary Fig. S1 at JXB online), confirming the reproducibility of RNA-Seq data.Pathway and GO term enrichment analyses The transcriptome data were submitted to the Mercator web tool to align with the public protein database, and 14 288 transcripts were located in at least one point in plant biologi-cal pathways. As shown in Table 1, pathway analysis revealedthat melatonin affected the expression of many genes involved in N metabolism, minor carbohydrate metabolism, TCA/org transformation, transport, hormone metabolism, metal han-dling, redox, and secondary metabolism (Table 1, group I). Other transcripts involved in stress response and metabolism were extensively changed after melatonin treatment (Fig. 6B ; Supplementary Fig. S2 at JXB online). These results indi-cated that melatonin treatment might induce a stress response in bermudagrass. The pathway analysis results were consist-ent with the study carried out by Weeda et al. (2014), whichFig. 3. Abiotic stress-induced ROS accumulation and MDA content were alleviated by exogenous melatonin in bermudagrass. (A–C) Quantifications of H 2O 2 content (A), O 2·– content (B), and MDA content (C) of 28-day-old plants with different treatments (control and 20 μM melatonin) under control, 300 mM NaCl, drought, and cold (4 °C) stress conditions on the designated days. The results shown are the means ±SEs, and bars with different letters above the columns of figures indicate significant differences at P <0.05 (Duncan’s range test).。
微藻的营养特性及其在畜牧业中应用的研究进展【论文】
微藻的营养特性及其在畜牧业中应用的研究进展摘要：微藻是一种分布广泛且营养物质含量高、光合能力强的自养植物。
微藻能合成多种拥有特殊生物活性的化合物, 还能提高动物的生长性能、增强机体免疫机能、改善畜产品品质、解决畜牧业的环境污染问题, 同时还可减轻食品与饲料以及燃料工业之间的竞争。
因此, 本文就微藻的营养特性及其对畜禽生长、免疫、产品品质等的影响进行综述, 为微藻在畜牧业中的开发和利用提供参考。
关键词：微藻; 生长; 免疫; 产品品质; 畜牧业;Abstract：Microalgae, a high photoautotrophy plant, is widely distributed and contained rich nutrient contents.M icroalgae can synthesize various special bioactive compounds, and play an important role in improving animal growth, immunity and meat quality, meanwhile, it can also curb environmental pollution and reduce competitive pressure among food, feed and fuel industry. Therefore, the nutritional characteristics of microalgae and its effects on animal growth and meat quality were reviewed in this paper so that it can provide a reference for the development and utilization ofmicroalgae in animal husbandry.Keyword：microalgae; grow th; immune; product quality; animal husbandry;到2050年, 全球人口预计将增加1/3, 估计粮食产量增加70%。
(武汉大学)分子生物学考研名词汇总
（武汉大学）分子生物学考研名词汇总●base flipping 碱基翻出●denaturation 变性DNA双链的氢键断裂，最后完全变成单链的过程●renaturation 复性热变性的DNA经缓慢冷却，从单链恢复成双链的过程●hybridization 杂交●hyperchromicity 增色效应●ribozyme 核酶一类具有催化活性的RNA分子，通过催化靶位点RNA链中磷酸二酯键的断裂，特异性地剪切底物RNA分子，从而阻断基因的表达●homolog 同源染色体●transposable element 转座因子●transposition 转座遗传信息从一个基因座转移至另一个基因座的现象成为基因转座，是由转座因子介导的遗传物质重排●kinetochore 动粒●telomerase 端粒酶●histone chaperone 组蛋白伴侣●proofreading 校正阅读●polymerase switching 聚合酶转换●replication folk 复制叉刚分开的模板链与双链DNA的连接区●leading strand 前导链在DNA复制过程中，与复制叉运动方向相同，以5’-3’方向连续合成的链被称为前导链●lagging strand 后随链在DNA复制过程中，与复制叉运动方向相反的，不连续延伸的DNA链被称为后随链●Okazaki fragment 冈崎片段●primase 引物酶依赖于DNA的RNA聚合酶，其功能是在DNA复制过程中合成RNA引物●primer 引物是指一段较短的单链RNA或DNA，它能与DNA的一条链配对提供游离的3’-OH末端以作为DNA聚合酶合成脱氧核苷酸链的起始点●DNA helicase DNA解旋酶●single-strand DNA binding protein, SSB 单链DNA结合蛋白●cooperative binding 协同结合●sliding DNA clamp DNA滑动夹●sliding clamp loader 滑动夹装载器●replisome 复制体●replicon 复制子单独复制的一个DNA单元称为一个复制子，一个复制子在一个细胞周期内仅复制一次●replicator 复制器●initiator protein 起始子蛋白●end replication problem 末端复制问题●homologous recombination 同源重组●strand invasion 链侵入●Holliday junction Holliday联结体●branch migration 分支移位●joint molecule 连接分子●synthesis-dependent strand annealing, SDSA 合成依赖性链退火●gene conversion 基因转变●conservative site-specific recombination, CSSR 保守性位点特异性重组●recombination site 重组位点●recombinase recognition sequence 重组酶识别序列●crossover region 交换区●serine recombinase 丝氨酸重组酶●tyrosine recombinase 酪氨酸重组酶●lysogenic state 溶原状态●lytic growth 裂解生长●transposon 转座子能够在没有序列相关性的情况下独立插入基因组新位点上的一段DNA序列，是存在与染色体DNA上可自主复制和位移的基本单位。
不同化学疏果剂对‘富士’苹果的疏除效果及品质影响
天津农$科学Tianjin Agricultural Sciences2021，27(3):17-24,28•作物栽培与设施园艺不同化学疏果剂对‘富士’苹果的疏除效果及品质影响王安丽李文胜周文静吴泽珍！，张振军2,胡安鸿"(1.新疆农业大学林学与园艺学院，新疆乌鲁木齐830052;2.阿克苏地8林业科学研究所，新疆阿克苏843000)摘要:对比不同化学疏果剂对‘红富士’苹果的疏除效果及成本，筛选出适宜阿克苏‘红富士’苹果的化学疏果剂及浓度，以减 少工人疏花成本，调控树体负载量，提升果品品质。
以盛果期‘新红1号’为试材，实采用正交试验设计方法果实6~8m m、10~12mm、14~16m m和18~20m m时喷施不同浓度西维因、萘乙酸、6-B A、疏果剂（山东），以人工疏果为对照，分析化学疏果剂 的疏除效果、成本以及对品质的影响。
同类同浓度的化学疏果剂疏除效果同，成本，对果实品质同。
过单果占比、双果占比、空台率、疏除率、果实横径和成本支出综合比较，盛果期树幼直径6!8m m时喷施800mg*L-1西维因的 疏除效果与人工疏果效果最相近，成本仅为人工疏果的13.080;幼果直径10~12m m时喷施1200mg*L-1的疏除效果与人工疏果效果最相近，成本为人工疏果的16.59%;幼果直径14!16m m时喷施400m g*L-1西维因效果与人工疏果效果最相近，成本为人工疏果的9.570;幼果直径18!20m m时喷施150m g •L-16-B A效果与人工疏果效果最相近，成本为人工疏果的 67.740。
对果实品质影响不显著。
关键词：富士苹果;化学疏果剂；果；本;品质中图分类号：S661.1文献标识码：A D O I 编码：10.3969/j.issn.l006 — 6500.2021.03.005Effects of Different Chemical Fruit Thinning Agents on the Fruit Thinning Effect and Quality of ；Fuji； Apple WANG Anli1,LI Wensheng1,ZHOU Wenjing1,WU Zezhen1,ZHANG Zhenjun2,HU Anhong2(1.College of Forestry and Horticulture, Xinjiang Agricultural University, Urumqi, Xinjiang 830052, China, 2. Aksu Regional Institute of Forestry Science, Aksu, Xinjiang 843000, China)Abstract: Comparison the effect and cost of chemical fruit thinners on ’red Fujiw apples, find suitable chemicals and its concentration which can well reduce costs and regulate the load and improve quality in Aksu. ’Xinhong No. K was used as the test material in the full fruit period. The orthogonal design method was used to spray different concentrations of carbaryl, NAA, 6-BA and fruit thinning agent (Shandong) on the fruit diameter of 6-8mm, 10-12 mm, 14-16 mm and 18-20 mm. The effect, cost and quality of chemical fruit thinning agent on the fruit thinning were analyzed. Different kinds and concentrations of chemical thinning agents have different thinning effects, different cost and different fruit quality# Through comprehensive comparison of single fruit set rate, double fruit set rate, empty fruit rate, flower thinning rate, fruit diameter and costs,when the fruit diameter was 6-8mm, high yield stage trees the effect of spraying 800 mg*L-1of Carbaryl was the closest to hand-thinned, and the cost was only 13.08% of the hand-thinned;when the fruit diameter was 10-12 mm, the effect of spraying 1200 mg*L-1of Carbaryl was the closest to the hand-thinned, and the cost was 16.59% of hand-thinned; the effect of spraying 400 m g*L-1of Carbaryl on 14-16 mm fruit was the closest to the effect of h an d- thinned, the cost was 9.57% of the hand-thinned; the effect of spraying 150 mg*L-16-B A on 18-20 mm was similar to the effect of hand-thinned, and the cost was 67#740 of hand-thinned# The main quality of the fruit was not significant difference#Key words：’Fuji’ apple; chemical thinning agent; fruit setting rate; cost; quality苹果 的水果，以 富，果，人，量 ]1]。
《MrDREB1调控扁蓿豆响应冷胁迫机制的初步研究》范文
《MrDREB1调控扁蓿豆响应冷胁迫机制的初步研究》篇一摘要：本研究初步探讨了MrDREB1基因在扁蓿豆响应冷胁迫过程中的调控机制。
通过分子生物学和遗传学手段，我们揭示了MrDREB1在冷胁迫下的表达模式及其对扁蓿豆的生理和分子响应的影响。
本研究不仅有助于深入理解植物抗寒机制，也为扁蓿豆的抗寒育种提供了理论依据。
一、引言植物在面对环境压力时，如冷胁迫，会通过一系列复杂的生理和分子响应机制来保护自身免受伤害。
DREB（Dehydration-responsive Element Binding）蛋白是植物响应非生物胁迫的重要转录因子之一。
MrDREB1作为DREB家族的一员，在扁蓿豆中可能发挥着重要的调控作用。
因此，研究MrDREB1在扁蓿豆响应冷胁迫中的调控机制，对于理解植物抗寒性具有重要意义。
二、材料与方法1. 材料选择：选取扁蓿豆作为实验材料，对其进行了基因组DNA的提取和纯化。
2. 基因克隆与表达分析：通过PCR技术克隆MrDREB1基因，并利用实时荧光定量PCR（qRT-PCR）技术分析其在冷胁迫条件下的表达模式。
3. 转基因植物构建与表型分析：构建MrDREB1过表达和沉默的转基因扁蓿豆，并对其生长表型及抗寒性进行观察和比较。
4. 生理生化分析：测定转基因植物在冷胁迫下的生理生化指标，如抗氧化酶活性、MDA含量等。
5. 分子机制研究：利用生物信息学手段预测MrDREB1的靶基因，并通过双荧光素酶报告系统验证其与冷胁迫相关基因的互作。
三、结果与分析1. MrDREB1基因的表达模式：qRT-PCR结果显示，在冷胁迫条件下，MrDREB1基因的表达量显著上升，表明其可能参与扁蓿豆的冷胁迫响应。
2. 转基因植物的表型分析：MrDREB1过表达的扁蓿豆表现出较强的抗寒性，而沉默株系则表现出对冷胁迫的敏感性。
这表明MrDREB1在扁蓿豆抗寒性中发挥了重要作用。
3. 生理生化分析：过表达MrDREB1的转基因扁蓿豆在冷胁迫下的抗氧化酶活性增强，MDA含量降低，表明其细胞膜系统受到的损伤较小。
油菜素甾醇类化合物合成研究进展
油菜素甾醇类化合物合成研究进展刘金娜1，2（1杨凌职业技术学院，陕西杨凌712100；2西北农林科技大学生命科学学院，陕西杨凌712100）摘要油菜素甾醇类化合物能够促进植物生长，提高作物抗性，调节激素平衡，广泛应用于农业生产。
但是，油菜素甾醇类化合物在植物中的含量极低，主要分布在花粉及幼嫩的组织中，提取分离工艺复杂，不易大量获取。
市售的油菜素甾醇类化合物主要通过人工合成的方式获得。
基于生物和化学合成两个方面的思考，本文总结了油菜素甾醇类化合物在植物体内的生物合成途径，并结合工业生产，阐述了油菜素甾醇类化合物相关产品的合成路线，提出了展望，以期为油菜素甾醇类化合物的工业化应用提供参考。
关键词油菜素甾醇类化合物；生物合成；化学合成；展望中图分类号O629.2文献标识码A文章编号1007-5739（2023）22-0067-06DOI：10.3969/j.issn.1007-5739.2023.22.019开放科学（资源服务）标识码（OSID）：Research Progress on Synthesis of BrassinosteroidsLIU Jinna1,2(1Yangling Vocational&Technical College,Yangling Shaanxi712100;2College of Life Sciences,North West Agriculture and Forestry University,Yangling Shaanxi712100) Abstract Brassinosteroids can promote plant growth,improve crop resistance,regulate hormone balance,which are widely used in agricultural production.However,the content of brassinosteroids in plants is extremely low,which mainly distributed in pollen and young tissues.The extraction and separation process of brassinosteroids is complex and difficult to obtain in large quantities.The commercially available brassinosteroids are mainly obtained through artificial synthesis.Based on two aspects of biological and chemical synthesis,this paper summarized the biological synthesis pathways of brassinosteroids in plants,expounded on the synthesis routes of brassinosteroids related products in combi-nation with industrial put forward,proposed prospects,so as to provide references for the industrial application of bras-sinosteroids.Keywords brassinosteroid;biological synthesis;chemical synthesis;prospect油菜素甾醇类化合物（brassinosteroids，简称BRs）最早从欧洲油菜的花粉中分离获得，具有促进植物生长、提高作物抗性、调节激素平衡的作用，广泛应用于农业生产。
原创英文文献翻译,英文原文名称见介绍(马铃薯在微波和对流干燥过程中的质量和结构变化)
这篇文章是用来测量马铃薯在微波和对流干燥过程中的质量和结构变化。
微波炉经过改良后，选择微波或者对流干燥模式干燥样品。
脱水马铃薯样品的质量品质以抗坏血酸残留量（VC）、复水能力以及具有收缩性的结构为准。
抗坏血酸马铃薯品质的重要指标，且与热变性有关。
抗坏血酸的恶化标志着一级反应情况，进一步的研究表明，取决于空气温度、微波力、湿度含量。
在微波干燥样品中，VC含量破坏减少。
样品的体积皱缩度显示其与湿度的线性关系。
在对流加工过程中，样品自始至终都会出现收缩性，然而，我们却发现微波干燥有两个收缩周期。
微波干燥样品有更高的复水能力。
关键词：对流干燥; 微波干燥; 马铃薯; 复水; 缩水; 维生素C目录1.简介2. 材料与方法3. 结果与讨论3.1.维生素C3.2.收缩性3.3. 复水4.结论参考文献1.简介在微波加工过程中，食物品质是消费者关注的重要指标之一。
微波干燥食品可以提高复杂的化学转换、化学反应。
,这些反应可以导致维生素的分解，脂肪氧化和美拉德反应。
而这些反应机制可以受浓度、温度、水分活度（aw）影响(Bruin & Luyben, 1980)。
经调查研究发现，在微波烹调中维生素会有所减少。
Rosen (1972) 曾研究讨论了微波食品及其相关食料的作用影响，微波量子能在各能级范围内比其他形式的电磁能（X- 和γ-射线）能量都低，也就使得分子和化学集团相互作用从而引起化学变化。
Gerster (1989)把热敏感和水溶性的维生素C 、B1和B2作为指示器来定性分析化学变化。
食品在微波炉中的烫熟、加热以及再加热过程中其维生素残留量可与常规加热方法相比较。
研究发现抗坏血酸的破坏速率随着aw值增加而增加，在解吸附系统中由于粘度的降低破坏速度会大大增加(Labuza, McNally, Gallagher, & Hawkes, 1972)。
Kirk, Dennison, Kokoczka, and Heldman (1977)研究发现，在复水食品体系中，抗坏血酸的稳定性受水分活度、湿度、氧气、贮藏温度的影响。
果胶与多酚相互作用机制及其对食品加工特性影响的研究进展
张璇，赵文，高哲，等. 果胶与多酚相互作用机制及其对食品加工特性影响的研究进展[J]. 食品工业科技，2024，45（1）：378−386.doi: 10.13386/j.issn1002-0306.2023030201ZHANG Xuan, ZHAO Wen, GAO Zhe, et al. Research Progress on the Interaction Mechanism of Pectin and Polyphenol and Their Effect on Food Processing Characteristics[J]. Science and Technology of Food Industry, 2024, 45(1): 378−386. (in Chinese with English abstract). doi: 10.13386/j.issn1002-0306.2023030201· 专题综述 ·果胶与多酚相互作用机制及其对食品加工特性影响的研究进展张 璇1，赵 文1,2，高 哲1，李美娇1，吴梦颖1，周 茜1,*（1.河北农业大学食品科技学院，河北保定 071000；2.河北省农产品加工工程技术研究中心，河北保定 071000）摘 要：果胶和多酚共存于植物性食品体系中。
除天然存在的果胶-多酚复合物外，在受到加热、高压、干燥等外力作用的食品加工过程中，两者会快速且自发地进行相互作用。
果胶与多酚之间的相互作用会影响食品的理化性质和功能特性。
本文总结了果胶与多酚相互作用的机制、内部和外部多重影响因素、主要的研究方法并结合 Langmuir 和Freundlich 常见的等温吸附模型对果胶与多酚之间的吸附行为进行描述和定量表征。
此外还探讨了两者相互作用对食品加工特性及多酚生物可利用性的影响，分析了该领域的研究方向和发展趋势。
关键词：果胶，多酚，相互作用，等温吸附模型，生物可利用性本文网刊:中图分类号：TS255.1 文献标识码：A 文章编号：1002−0306（2024）01−0378−09DOI: 10.13386/j.issn1002-0306.2023030201Research Progress on the Interaction Mechanism of Pectin and Polyphenol and Their Effect on Food Processing CharacteristicsZHANG Xuan 1，ZHAO Wen 1,2，GAO Zhe 1，LI Meijiao 1，WU Mengying 1，ZHOU Qian 1, *（1.College of Food Science and Technology, Hebei Agricultural University, Baoding 071000, China ；2.Engineering Technology Research Center for Agricultural Product Processing of Hebei, Baoding 071000, China ）Abstract ：The pectin and polyphenols that co-exist in plant-based food systems form complexes in natural conditions and interact quickly and spontaneously during food processing due to external forces, such as heating, high pressure, and drying.The interaction can affect the physicochemical properties and functional properties of foods. This review summarizes the mechanisms, multiple internal and external influencing factors, and main research methods involved in pectin and polyphenol interaction, while their adsorption behavior is described and quantitatively characterized using the isothermal adsorption model commonly used by Langmuir and Freundlich. In addition, the impact of pectin and polyphenol interaction on food processing characteristics and polyphenol bioavailability is also discussed, and the future research prospects and development trends in this field are analyzed.Key words ：pectin ；polyphenol ；interactions ；isothermal adsorption models ；bioavailability果胶是一种酸性杂多糖，广泛存在于蔬菜、水果和谷物等植物细胞壁中，在人类健康中发挥着重要的作用[1]。
日粮添加蚕豆皮对湖羊生长性能、屠宰性能、器官发育和肉品质的影响
第 32 卷 第 10 期Vol.32，No.10162-1722023 年 10 月草业学报ACTA PRATACULTURAE SINICA 王钊， 刘静， 于昊， 等. 日粮添加蚕豆皮对湖羊生长性能、屠宰性能、器官发育和肉品质的影响. 草业学报， 2023， 32（10）： 162−172.WANG Zhao ， LIU Jing ， YU Hao ， et al . Effects of dietary broad bean skin on growth rate ， slaughter performance ， organ development and meat quality of Hu sheep. Acta Prataculturae Sinica ， 2023， 32（10）： 162−172.日粮添加蚕豆皮对湖羊生长性能、屠宰性能、器官发育和肉品质的影响王钊1，刘静1，于昊1，李鹏2，牛伟强2，万永杰1，张艳丽1，茆达干1*（1.南京农业大学动物科技学院，江苏 南京210095；2.启东瑞鹏牧业有限公司，江苏 启东226200）摘要：本试验旨在研究日粮添加蚕豆皮对湖羊生长性能、屠宰性能、器官发育及肉品质的影响。
60只4月龄健康湖羊公羊［（27.00±2.00） kg ］随机分为4组（n =15，每组3个重复，每个重复5只羊），分别饲喂含蚕豆皮0%（对照组C ）、10%（组Ⅰ）、20%（组Ⅱ）和30%（组Ⅲ）的日粮，试验期60 d 。
结果表明：与对照组相比，添加不同比例的蚕豆皮组湖羊体重、平均日采食量和平均日增重均极显著提高（P <0.01）；蚕豆皮组Ⅲ的胴体重（19.62±0.73 vs 17.75±0.86） kg 和宰前活重（37.22±1.01 vs 34.76±0.71） kg 极显著提高（P <0.01），眼肌面积显著提高（35.84±2.47 vs 27.84±0.13 cm 2，P <0.05）；肝脏重量有提高趋势（670.00±73.37 vs 588.00±49.87 g ，P =0.071），瘤胃重量（659.40±66.44 vs 548.00±75.48） g 和小肠重量（1107.80±150.56 vs 901.00±41.32） g 显著提高（P <0.05）；肌纤维横截面积极显著降低（584.67±32.01 vs 832.90±53.48 μm 2，P <0.01），肌肉谷氨酸含量极显著提高（37.74±1.64 vs 13.19±3.38 mg ·g -1，P <0.01），精氨酸含量（19.08±1.28 vs 11.25±2.39） mg ·g -1和非必需氨基酸总量（118.44±1.98 vs 90.59±9.56） mg ·g -1显著提高（P <0.05），缬氨酸含量（12.40±1.09 vs 7.98±1.61 mg ·g -1，P =0.086）和必需氨基酸总量（135.25±3.51 vs 106.79±11.14 mg ·g -1，P =0.071）有上升趋势。
纳米抗菌材料的研究进展
纳米抗菌材料的研究进展摘要：纳米抗菌材料中抗菌剂以纳米尺寸分散，具有高比表面积和高反应活性，抗菌材料整体的抗菌效果较传统抗菌剂有显著提高，更能显著的抑制细菌、真菌等微生物的生长和繁殖，并改善抗菌材料的力学性能，引起了国内外研究者的广泛关注。
本文对具有广泛应用前景的金属型、光催化型、季铵盐或季磷盐修饰无机纳米颗粒等纳米抗菌剂的研究及应用情况进行了综述。
关键词：纳米、抗菌剂、金属型、光催化型、无机纳米颗粒The research development of nano-antibacterial materialsAbstract:Antibacterial agents are dispersed as nano-sized particles in nano-antibacterial material. Because of the high surface area and high reactivity of antimicrobial agents, the overall antibacterial properties of nano-antibacterial materials have increased more significantly than the conventional antibacterial agents, which have more effect on inhibiting the growth and reproduction of microbial, such as bacteria, fungi and other microbial. Moreover, antibacterial agents can improve the mechanical properties of antibacterial material. In this paper, the research and application development of some kinds of nano-antibacterial materials with broad application prospects is reviewed, such as metal-based, light catalytic nano-antibacterial materials, and inorganic nano-sized materials modified by quaternary ammonium or quaternary phosphorus salt.Keywords: nano-sized, antibacterial agent, metal, light catalytic, inorganic nanoparticles 随着科技的发展，生活水平的提高，人们对自身居住、工作、生活的环境卫生要求进一步提高，促进了抗菌技术和抗菌材料的快速发展。
马尾松与乡土阔叶树种凋落叶木质素降解的混合效应
热带亚热带植物学报2022, 30(1): 19 ~ 30Journal of Tropical and Subtropical Botany马尾松与乡土阔叶树种凋落叶木质素降解的混合效应李勋1, 张艳1, 覃宇2, 张健3*(1. 四川民族学院，横断山区生态修复与特色产业培育研究中心，四川康定626001；2. 阿坝师范学院，四川汶川623002；3. 四川农业大学林学院，生态林业工程重点实验室，长江上游生态安全协同创新中心，成都611130)摘要：为了解森林凋落叶分解过程中木质素的释放规律，对马尾松(Pinus massoniana, P)、檫木(Sassafras tzumu, S)、香樟(Cinnamomum camphora, C)和香椿(Toona sinensis, T)凋落叶分解过程中的木质素降解率进行了研究。
结果表明，大部分混合凋落叶的木质素在分解过程中出现富集现象，PT和PC组合的木质素含量在第1年较高，之后降低。
而PS、PST、PSC、PCT和PSCT组合在0~6、0~9和15~18个月表现出富集现象，其余时期降低。
在不同分解时期，部分混合凋落叶组合的木质素降解率表现出非加和效应，呈协同效应，以春季和夏季的协同效应较强，秋冬季较弱。
此外，PSCT6121、PSC622、PS64和PC64的木质素降解率在大部分分解时期(≥6/8)表现出协同效应。
因此，马尾松与乡土阔叶树种凋落叶混合后促进了木质素的降解，在马尾松人工林改造过程中，与乡土阔叶树种适当混种，可促进凋落叶中木质素的降解。
关键词：马尾松；乡土树种；凋落物；木质素doi: 10.11926/jtsb.4408All Rights Reserved.Mixed Effects on Lignin Degradation in the Litter Leaves of Pinusmassoniana and Native Broad-leaved Tree SpeciesLI Xun1, ZHANG Yan1, QIN Yu2, ZHANG Jian3*(1. Research Center for Ecological Restoration and Characteristic Industry Cultivation in Hengduan Mountains Region, Sichuan Minzu College, Kangding626000, Sichuan, China; 2. Aba Teachers University, Wenchuan 623002, Sichuan, China; 3. Key Laboratory of Forestry Ecological Engineering in Sichuan,Collaborative Innovation Center of Ecological Security in the Upper Reaches of Yangtze River, Sichuan Agricultural University,Chengdu 611130, China)Abstract: To understand the release rule of lignin in the decomposition process of forest leaf litter, the lignindegradation rate of leaf litter of Pinus massoniana(P), Sassafras tzumu(S), Cinnamomum camphora(C) andToona sinensis(T) was studied. The results showed that lignin in most of mixed litter was enriched duringdecomposition. The lignin content in combination of PT and PC was high in the first year, and then decreased.However, the lignin content in combination of PS, PST, PSC, PCT and PSCT were enriched at 0-6, 0-9 and 15-18 months, and decreased at other periods. At all decomposition stages, the degradation rate of lignin in somemixed litters showed synergistic effect rather than additive effect, the synergistic effect was stronger in summerand winter than in other seasons. Besides, the lignin degradation rate of PSCT6121, PSC622, PS64 and PC64收稿日期: 2021-03-09 接受日期: 2021-05-19基金项目：国家自然科学基金项目(31370628); 四川省科技支撑计划项目(12ZC0017); 四川民族学院自办科研项目(XYZB2003ZA, XYZB2016ZB); 四川民族学院特色科研孵化项目(KBFH2103); 四川省大学生创新创业训练计划项目(S202011661092, S202011661106, S202011661090)资助This work was supported by the National Natural Science Foundation of China (Grant No. 31370628), the Project for Science and Technology Support ofSichuan (Grant No. 12ZC0017), the Project for Scientific Research of Sichuan Minzu College (Grant No. ZYZB2003ZA, XYZB2016ZB), the Project forCharacteristic Research Incubation of Sichuan Minzu College (Grant No. KBFH2103), and the Project for Innovation and Entrepreneurship Training forCollege Students in Sichuan (Grant No. S202011661092, S202011661106, S202011661090).作者简介：李勋，男，博士，主要从事长江中上游马尾松低效人工林改造。
不饱和脂肪酸与炎症性肠病因果关系的孟德尔随机化分析
不饱和脂肪酸与炎症性肠病因果关系的孟德尔随机化分析*李 健1 高建淑1,2 赵可可1,2 高鸿亮1,2#新疆医科大学第一附属医院消化病二科1（830054） 新疆医科大学研究生学院2背景：炎症性肠病（IBD ）是一种慢性复发性胃肠道炎症性疾病，包括溃疡性结肠炎（UC ）和克罗恩病（CD ）。
目前尚不清楚不饱和脂肪酸与IBD 之间是否存在因果关系。
目的：采用两样本孟德尔随机化分析探究不饱和脂肪酸与IBD 之间的因果关系。
方法：不饱和脂肪酸和IBD 的全基因组关联研究（GWAS ）数据均来源于网络公开数据库。
采用逆方差加权分析法进行两样本孟德尔随机化分析，使用加权中位数法和MR⁃Egger 回归分析验证因果效应，以OR 及其95% CI 评价不饱和脂肪酸与IBD 风险的因果关系。
结果：ω⁃6脂肪酸与CD 无直接因果关系，与UC 有直接因果关系，逆方差加权分析结果显示ω⁃6脂肪酸基因水平每增加一个标准差，UC 风险增加16%（OR =1.16，95% CI : 1.00~1.36，P =0.04）。
而ω⁃3脂肪酸、单不饱和脂肪酸与IBD 之间均未发现因果关系。
结论：ω⁃6脂肪酸可能仅与UC 存在因果关系，ω⁃3脂肪酸、单不饱和脂肪酸与IBD 之间均未发现因果关系。
关键词 脂肪酸类，不饱和； 脂肪酸类，ω⁃6； 炎症性肠病； 结肠炎, 溃疡性； Crohn 病； 孟德尔随机化分析Causal Association Between Unsaturated Fatty Acids and Inflammatory Bowel Disease: A Mendelian Random ⁃ization Analysis LI Jian 1, GAO Jianshu 1,2, ZHAO Keke 1,2, GAO Hongliang 1,2. 1The Second Department of Gastroenterology, the First Affiliated Hospital of Xinjiang Medical University, Urumqi (830054); 2Graduate School of Xinjiang Medical University, UrumqiCorrespondence to:GAOHongliang,Email:*************************.cnBackground: Inflammatory bowel disease (IBD) is a chronic recurrent inflammatory disease of gastrointestinal tract including ulcerative colitis (UC) and Crohn's disease (CD). It is unclear whether there is a causal association between unsaturated fatty acids and IBD. Aims: A two ⁃sample Mendelian randomization analysis was used to explore the causal association between unsaturated fatty acids and IBD. Methods: The data of the genome⁃wide association study (GWAS) of unsaturated fatty acids and IBD were obtained from web ⁃based public databases. Two ⁃sample Mendelian randomization analysis was performed by using inverse⁃variance weighted analysis, and weight median estimator and MR⁃Egger regression were conducted to validate the association of the causal effect. The causality of unsaturated fatty acids on the risk of IBDwas evaluated by OR and 95% CI . Results: No direct causal association was found between ω⁃6 fatty acids and CD, and a direct causal association was found with UC. Inverse⁃variance weighted analysis showed a 16% increase in the risk of UC for each standard deviation increase in ω⁃6 fatty acid gene levels (OR =1.16, 95% CI : 1.00⁃1.36, P =0.04). However, no causal association was found between ω⁃3 fatty acids, monounsaturated fatty acids and IBD. Conclusions: ω⁃6 fatty acids may be onlycausally associated with UC, and no causal association is found between ω⁃3 fatty acids, monounsaturated fatty acids and IBD.Key words Fatty Acids, Unsaturated; Fatty Acids, Omega⁃6; Inflammatory Bowel Disease; Colitis, Ulcerative; Crohn Disease; Mendelian Randomization AnalysisDOI ： 10.3969/j.issn.1008⁃7125.2023.01.003*基金项目：新疆维吾尔自治区自然科学基金杰出青年科学基金项目（2022D01E25）炎症性肠病（inflammatory bowel disease, IBD ）是一种免疫介导的胃肠道慢性炎症性疾病，包括溃疡性结肠炎（ulcerative colitis, UC ）和克罗恩病（Crohn's disease, CD ），临床特征以腹痛和腹泻为主。
effect of supplemental humate at different levels on the growth performance slaughter and carcass
International Journal of Poultry Science 3 (6): 406-410, 2004© Asian Network for Scientific Information, 2004Effect of Supplemental Humate at Different Levels on the Growth Performance,Slaughter and Carcass Traits of BroilersMevlüt Karaoglu, Muhlis Macit, Nurinisa Esenbuga, Hülya Durdag, Leyla Turgut and Ö. Cevdet Bilgin Department of Animal Science, Collage of Agriculture, Ataturk University, 25240-Erzurum, TurkeyE-mail: mmacit@.trAbstract: The current trial was carried out to determine the influence of supplemental humates including humic, fulvic and ulmic acids and some microminerals on the performance and carcass traits of broilers.A study was conducted with total 240 male broiler chicks (Ross-308), received from a commercial hatcheryat 1 day of age. Chicks were allocated to four dietary treatments (H, H, H and H groups) as completely0123randomized experimental design . Feed and water were offered for ad libitum consumption and lighteningwas continuous throughout experimental period. A basal diet (H), basal diet plus 0.10 (H), 0.20 (H) and0120.30 % (H) humate (Farmagulator DRY, Humate, Farmavet International Inc., Kocaeli 41400, Turkey) were3TMoffered during experimental period. All birds were housed in batteries from 1 to 21 days, and in grower broiler pens to 49 days in the Application and Research Farm of the Agricultural Faculty, Atatürk University. At the end of the trial all birds were slaughtered. Feed intake and body weight gains were recorded weekly per pen.Final body weights were 2525, 2494, 2646 and 2546 g for H, H, H and H groups respectively, and the0123difference was not significant. Average daily weight gains were 51.8, 49.8, 52.9 and 49.9 g, respectively, and the supplementation had statistically no significant effect on this parameter. Daily feed consumptions were 103.2, 95.6, 104.4 and 98.6 g and the difference between control and treatment groups was significant (P<0.05). FCR values were 1.87, 1.84, 1.86 and 1.85. At the end of the trial, hot carcass weights and yields were 1874, 1913, 1912 and 1884 g and 75.78, 75.51, 75.55 and 75.55 %, and difference was not significant.There was no different in offal weights. Abdominal fat pad weights were found to be 35.5, 40.33, 40.0 and32.16 g, respectively. Difference among the groups in terms of abdominal fat weights was not statisticallysignificant. The mortality was 1.8, 0.0, 0.0 and 0.0 % for H, H, H and H and there was no significant0123different among the groups. In conclusion, although humate supplementation to diets of broilers had no effect on performance, slaughter and carcass characteristics, a slightly improvement was observed in FCRfor H group fed with diet containing 0.1 % humate. In addition, it was not observed dead chick in humate 1groups while 1.8 % of mortality in control group.Key words: Humate, broiler, performance, slaughter, carcassIntroductionFeed is the major item of cost in the production of poultry meat and eggs. In addition to feedstuffs, some microbiological cultures and various chemical agents such as probiotics, prebiotics, antibiotics, humates and enzymes, etc. have been adding to animal diets as feed additive to enhance nutrient utilization, improve feed conversion efficiency and maintain health status. But during the past several years, inclusion of probiotics and humates in rations is preferable to antibiotics, primarily because they cause no harmful effects on consumers (Yörük et al., 2004).Humates, a part of fertilizers, are derived from plant matter decomposed by bacteria (Seen and Kingman, 1973) and contain humus, humic acid, fulvic acid, ulmic acid and some microelements (Stevenson, 1994). Previous studies related to humates have focused mainly on the growth of germinal tissue in seed. The idea of using humates as feed additives in animal nutrition is new. At first humates were used as a part of replacement therapy for digestive system disturbances such as malnutrition and diarrhea and increased for feed conversion efficiency in calves, dogs and cats. Remarkable changes in electrolyte balance and enhancements in immune potency of poultry (Yörük et al., 2004; Parks et al., 1986) in response to humate supplementation have been reported. In addition, consistent agreements in the limited numbers of published articles show that humates promote growth by altering partitioning of nutrient metabolism (Parks, 1998), reducing mortality (Eren et al., 2000) and improving feed conversion efficiency (Yörük et al., 2004; Eren et al., 2000).The objective of the present study was to investigate the effect of supplementation of humate on performance, slaughter and carcass characteristics of broilers. Materials and MethodsChicks and diets: The Research Animal Ethic Committee of Atatürk University approved this experimental protocol. A study was conducted with total 240 male broiler chicks (Ross-308), received from acommercial hatchery (KÖY-TUR) at 1 day of age. Chicks,(humic, fulvic, ulmic and humatomelanic acids), 663.3initially about 40 g, were randomly allocated to four SiO and other minerals (Mn, 50 mg; Zn, 60 mg; Fe, 60dietary treatments and were housed in batteries from 1mg; Cu, 5 mg; Co, 0.2 mg; I, l mg; Se, 0.5 mg; and Al, Na,to 21 days, and in grower broiler pens from 21 to 49K, Mg and P in trace amounts). The experimental groups days in the Application and Research Farm of the consisting four dietary treatments were: 1) H was fed Agricultural Faculty, Atatürk University. The ambient with only basal diet, 2) H was fed with basal diet plus temperature was thermostatically controlled. This0.1 % humate, 3) H was fed with basal diet plus 0.2 %temperature was set at 33 C the 1 day of thehumate, and 4) H was fed with basal diet plus 0.3%o stexperiment and decreased 1 C every 3 day thereafter humate during experimental period. The weights of o rdfor the duration of the experimental period. The chicks chickens and feed consumptions were weekly recorded,were weighed and distributed randomly into four per pen. Mortality was recorded as it occurred and treatment groups. Each treatment group was replicated percentage mortality was determined at the end of the six times as subgroups, comprising of 10 birds each.study.Feed and water were offered for ad libitum consumption,At the end of the trial, the birds were held for 10-12h and lightning was continuous throughout experimental without food and water prior to the determining of final period. All birds were fed a starter diet from day 1 to 21,body weights. Each bird was weighed live, slaughtered and a finisher diet to 49 days. Diets were formulated and allowed to bleed for 180 s, previously determined to according to NRC recommendations (1994). Feed be sufficient time for bleeding. The bird was then composition was analyzed by the AOAC (1990) and reweighed to calculate blood weight by difference, sub-shown in Table 1. scalded at 50-52 E C for approximately 30 s, and placedin a rotary drum plucker for 30 s to remove feathers. Table 1: Composition of starter and grower dietsStarter Grower diet diet Ingredients and composition (kg ton )-1Ground corn 462.9462.3Soybean meal(480 g CP kg feed)221.4210.0-1Full fat soy 125.0100.0Ground wheat 100.0100.0Fish meal 40.025.0DCP 16.717.3Ground limestone 5.913.0Salt (NaCl) 2.5 2.6Soya oil 15.833.1Poultry fat -15.0Lysine -0.8DL-methionine 2.4 2.5Choline cloride 0.40.4Trace mineral premix 3.0 3.01Vitamin premix 5.0 5.01Coccidiostat 1.0 1.0Lasolocyde - 1.0Analysis (g kg , dry matter basis)-1 2Dry matter 940.0930.0Crude protein 220.0200.0Ash 67.459.6Ether extract 44.049.9Crude fiber 74.660.5N-free extracts 570.0560.0ME (kcal kg )30003100–1Premixes were formulated to meet recommended levels for minerals and vitamins (NRC, 1994).Calculated by AOAC (1990).2Humate was added to starter and finisher diets of chicks at different levels (0.0, 0.1, 0.2 and 0.3%). Each kg of humate contained 160 mg polymeric polyhydroxy acid20 1 23The bird was reweighed to calculate feather weight by difference. The bird then processed by removing the head, neck, shanks and feets, and was eviscerated by cutting around the vent removing the viscera without disturbing the fat pad along the abdominal wall. The heart, liver and gizzard were dissected from the viscera,and the gizzard was cut open and rinsed of its content.All of the above components were weighed individually.The weight of the remaining gastrointestinal tract,including fat and mesentery, was determined by difference between the whole picked bird weight minus the various components and dressed carcass weight.The lungs were left in the eviscerated carcass. The carcass was immersed in water 4 C and washed. Upon o removal from water, the carcass was drained for 10 min,weighed for hot carcass weight and yield, bagged and stored at 3 ± 0.5 C for 24h. (Yalçin et al ., 1999). Upon o removal from the bag, the fat pad lining abdominal wall was removed from carcass, and both of fat pad and carcass were weighed to determine a cold carcass weight and yield. All of the evisceration steps and cutting procedures mentioned above performed by two experienced people according to Brake et al . (1993).Statistical Analysis: The data were subjected to analysis using a General Linear Model procedure of SAS (SAS Institute, 1996) for the completely randomized experimental design. Differences between means were determined by Duncan’s multiple range test at significance level of P<0.05.Results and DiscussionGrowth Performance and Feed Efficiency: The average daily weight gain, daily feed consumption and feed conversion values of treatment groups are shown inTable 2: Daily weight gain, feed consumption and feed conversion ratios of broilers during experimental periodAge (weeks)Daily Weight Gain (g)---------------------------------------------------------------------------------------------------------------------------------Groups n 1234567AverageH 612.929.645.255.380.184.055.751.80 bH 612.428.342.658.781.853.370.649.81bH 612.631.044.866.184.771.060.052.92aH 612.828.942.257.380.369.458.149.93 bSEM ±0.69±2.17±2.22±2.11±2.30±10.74±8.77±1.14Significance Ns Ns Ns *Ns Ns Ns Ns Daily Feed Consumption (g) H 617.246.579.4116.1155.5174.4133.2103.20 b a a H 617.138.4 68.1111.1165.8129.9139.395.61 ab b b H 617.443.177.4117.4168.4150.5156.4104.42 a ab a H 617.6 38.670.2115.5158.3147.1142.998.63ab ab ab SEM ±0.57±1.50 ±1.35±2.99±3.82±3.00±8.34±2.06Significance Ns Ns Ns Ns ***Ns *Feed Conversion Ratio H 6 1.33 1.57 1.74 2.10 1.94 2.08 2.30 1.870 H 6 1.31 1.36 1.60 1.91 2.03 2.44 1.97 1.811H 6 1.39 1.39 1.73 1.77 1.99 2.12 2.60 1.862H 6 1.38 1.33 1.66 2.01 1.97 2.13 2.45 1.853SEM ±0.06±0.10±0.10±0.08±0.06±0.14±0.42±0.16Significance Ns Ns Ns Ns Ns Ns Ns Ns **: (P<0.01); *: (P<0.05); NS: Non significant. : Means within a column with no common superscripts differ significantly (P<0.05). a,bTable 2.improvement was observed in H for FCR as compared It is apparent that the difference between control (H )with the H group. Orban et al . (1993) reported that feed 0and treatment groups in terms of daily weight gain (H ,conversion ratios ranged from 1.72 to 1.90. FCR,1H and H ) was not significant at the 3, 5, 6 and 7 wks of determined herein, was closely or better than the 2 3the trial. The daily weight gain of H group was foundfindings of Summers et al . (1992). The use of increasing 2statistically higher than that of H , H and H groups at 4levels of humate (H and H groups) didn’t improve 0 1 3thweek of experimental period. In generally, it was performance traits of broilers.observed that there was no significant difference In addition, survival rates of broilers were determined in among the treatment groups in this characteristic (Table present study. Mortality for control group fed the basal 2). However, H group produced an important increase diet was higher than that for groups fed diets containing 2 in daily weight gain, as compared with the other groups.humate at different levels. The mortality was 1.8, 0.0, 0.0Table 2 presents the daily feed consumption and feed and 0.0 % for H , H , H and H , respectively and there conversion ratio (FCR) according to ages (wks) of was no significant different among the groups. These broilers. It was determined that there was significant values were lower than findings ranged from 2.7 to 6.52difference between control and other groups (P<0.05) in reported by Richter at al . (1999) and Pradhan et al .daily feed consumption. It was observed that the highest (1998) for broilers fed diets containing probiotic at feed consumption was in H group while the lowest one different levels. Little is known about the mechanism by 2in H group. Karaoglu and Durdag (2003) found that the which humate supplementation enhances the life span 1 daily feed consumptions for control and probiotic-treated and improves production efficiency. But, data obtained groups were 94.5, 95.0 and 96.3 g, and these findings from present study suggest that humate were similar to the results of the current study.supplementation may benefit poultry production. In a The feed efficiency was not affected by humate study, it was reported that supplemental humate supplementation during experimental period. Table 2alleviates toxicity of Cd in chickens (Herzig et al ., 1994)shows that the FCR values were more or less similar up by reducing deposition of toxic metals in organs. to 6wk for all groups. At the end of the trial, although th humate didn’t have an appreciable effect on FCR Slaughter and Carcass Traits: Producing lean poultry (P>0.05). The feed efficiency of H group was slightly meat to meet the demands of the consuming public is a 1better than those of the other groups. Approximately 2 %-major objective of the broiler industry. One of the major10 2 30 1 2 3Table 3: Effect of humate on the slaughter and carcass characteristics of broilers Parameters H H H H SEM±Significance0123------------------------------------------------------------------------------------------------------------Slaughter CharacteristicsBody weight before slaughter (g)247325332528247761.65Ns Body weight after slaughter (g)238524492454240362.25Ns Body weight after plucking (g)219322402249220358.14Ns Blood 88847474 6.4Ns Feathers 117125130120 5.6Ns Head 76847580 3.4Ns Feet and shanks 10910499104 3.4Ns Offals 105117112117 6.2Ns Heart 101010110.6Ns Liver 42424343 2.2Ns Gizzard 43414043 2.2Ns Abdominal fat pad weight (g) 36404032 4.5Ns Hot carcass weight (g) 1874191319121884 51.3Ns Hot carcass yield (%)767676760.5Ns Cold carcass weight (g) 1847188918821856 49.1Ns Cold carcass yield (%) 757574750.5Ns Carcass Characteristics Wing weight (g) 209206212203 6.9Ns Leg weight (g) 74877474570926.7Ns Breast weight (g) 76378780279023.9Ns Neck weight (g) 96979789 5.7Ns Tail weight (g) 28232627 2.61Ns Ns: Non-significant; ±, Standard error of samples.items is to obtain the higher percentage yield of saleable observed in FCR for H group fed with diet containing 0.1products and consequently to increase the edible 3% humate. In addition, it was not observed dead chick in portions. The results on the slaughter weight and blood,humate groups while 1.8 % of mortality in control group.feather, head, feet and shanks and gastrointestinaltracts as inedible portions, and gizzard, heart and liver as edible organs, and carcass weights and yields are shown in Table 3. As shown, the differences among the groups in terms of all slaughter and carcass characteristics were not significant in present study. Dickens and Lyon (1993) noted that blood loss were 2.64 and 2.86 % of live weight, in our study it was around 3.2% and H had the highest blood volume as compared 0 with control and the other treatment groups. Brake et al .(1993) reported that the slaughter weight, blood,feathers, head, feet and gastrointestinal tract were 2547.4, 98.1, 108.1, 61.0, 114.3 and 170.8 g, and heart,liver, gizzard, abdominal fat pad, hot and cold carcass weights were 13.3, 42.3, 40.4, 43.3, 1789.3 and 1771.6g. In generally, findings obtained from the present study were higher than these results reported by Brake et al .(1993). The findings on carcass yields values were in agreement with results reported by Eren et al . (2000)and Kocabagli et al . (2002).In conclusion, although humate supplementation to diets of broilers had no effect on performance, slaughter and carcass characteristics, a slightly improvement was1 ReferencesAOAC, 1990. Official methods of analysis of theAssociation of Official Analytical Chemist. Vol. I, 15th ed., Arlington, VA.Brake, J., B. Havenstein, S.E. Scheideler, B.R. Ferketand D.V. Rives, 1993. Relatinship of sex, age, and body weight to broiler carcass yield and offal production. Poult. Sci., 72: 1137-1145.Dickens, J.A. and C.E. Lyon, 1993. Effect of two stunningvoltages on blood loss and objective texture of meat deboned at various post-mortem times. Poult. Sci.,72: 589-593.Eren, M., G. Deniz, S.S. Gezen and I.I. Türkmen, 2000.Broyler yemlerine katilan humatlarin besi performansi, serum mineral konsantrasyonu ve kemik külü üzerine etkileri. Ankara Univ. Vet. Fak.Derg., 47: 255-263.Herzig, I., J. Hampl, V.A. Docekalova, B. Psarkova andJ.V. Vlcek, 1994. The effect of sodium huminate on cadmium deposition in the organs of chickens. Vet.Med. (Praha) 39: 175-185.Karaoglu, M., and H. Durdag, 2003. Dietary probiotic Richter, G., I. Kühn, and H. Köhler, 1999. Test ofeffect on the growth, slaughtering and carcass traits in broiler chickens slaughtered at different ages.Research Project Final Report. College of Agriculture, Atatürk University, Erzurum-Turkey. BAP-2002/17. Kocabagli, N., M. Alp, N. Acar and R. Kahraman, 2002.The effects of dietary humate supplementation on broiler growth and carcass yield. Poult. Sci., 81: 227-230.NRC, 1994. National Research Council, Nutrient Requirements of Poultry. 9th Revised Editition.National Academy Press, Washington, DC. 7:11-19. Orban, J.I., D.A. Roland Sr., K. Cumnis and R.T. Lovell, 1993. Influence of large doses of Ascorbic acid on performance, plasma calcium, bone characteristics, eggshell quality in broilers and Leghorn hens. Poult.Sci., 72: 691-700.Parks, C., P.R. Ferket, L.N. Thomas and J.L. Grimes, 1986. Growth performance and immunity of turkeys fed high and low crude protein diets supplemented with Menefee humate. Poult. Sci., 75: 138-143. Parks, C. W., 1998. The use of Menefee Humatein typical and low-crude protein diets for turkey toms and in the bioremediation of petroleum-contaminated soil amended with poultry litter as a co-substrate and nutrient source. M.S. Thesis. North Carolina State University, Raleigh, NC.Pradhan, R.N., G. Sahoo, P.K. Mishra, L.K. Babu, S.C.Mishra and L.M. Mohapatra, 1998. Role of probiotics on performance of broiler chicks. Ind. J. Anim. Prod., Manage., 14: 80-83. Poultry Abstracts 2000 Vol. 26 No: 3-643.Toyocerin in broiler fattening. Poultry Abstracts 2000 Vol. 28 No. 5-355.SAS, 1996. SAS Institute Inc., NC, USA.Seen, T.L. and A.R. Kingman, 1973. A review of humus and humic acids. Research Series Report No: 145.South Carolina Agricultural Experiment Station, Clemson, SC.Stevenson, F.J., 1994. Humus-chemistry genesis , composition, reactions. John Wiley and Sons, New York, NY.Summers, J.D., D. Spratt and J.L. Atkinson, 1992. Broiler weight gain and carcass composition when fed diets varying in amino acid balance, dietary energy and protein level Poult. Sci., 71: 263-273.Yalçin, S., S. Özkan, Z. Açikgöz and K. Özkan, 1999. Effect of dietary methionine on performance, carcass characteristics and breast meat composition of heterozygous naked neck (Na/na+) birds under spring and summer conditions. Br. Poult. Sci., 40: 688-694.Yörük, M.A., M. Gül, A. Hayirli and M. Macit, 2004. The effects of supplementation of humate and probiotic on egg production and quality parameters during the late laying period in hens. Poult. Sci., 83: 84-88.。
一株野鸟源H16N3亚型禽流感病毒的遗传进化分析与感染能力评估
中国病原生物学杂志2020年12月第15卷第12期•1370•Journal of Pathogen Biology Dec.2020,Vol.15.No.121）01:10.13350/j.cjpb.201202•论著•一株野鸟源H16N3亚型禽流感病毒的遗传进化分析与感染能力评估*孙雷云李元果张醒海….赵梦琳；.胡鑫宇；.王铁成‘，孙伟洋'，冯娜:赵永坤杨松涛夏成柱「，孟德荣‘.高玉伟心…（1•占林农业大学动物科学技术学院，吉林长春130118；2.军事医学研究院军事兽医研究所；3.吉林大学；4.沧州师范学院〉目的了解H16N3亚型禽流感病毒的遗传进化特征及其化物学特性，为野鸟源禽流感病毒预警提供科学依据。
方法采集途径我国中东部地区重要候鸟栖息地的野鸟粪便样品.经处理后接种SPF鸡胚.获得具有血液凝集特性病原体.经全底因测序确定病毒亚型。
选取H16亚型流感病毒构建系统发育树并进行分子特性分析。
检测病毒受体结合特性.并进行小鼠和家禽感染试验.评价该病毒对哺乳动物和家禽的致病性。
结果分离到1株病原体（CZ-638）,经全基因组测疗;及电镜观察.确定为H16N3W：型禽流感病毒。
在系统发育树种，该带株位于欧亚谱系分支。
氨基酸位点分析显示.HA蛋白裂解位点为INERl GI.F.符合低致病性禽流感病毒分子特征.受体结合域的228位点由G （It氨酸）突变为S"纟訊酸）。
该病毒株能够凝集绵羊红细胞、正常鸡红细胞及仅有SA«2,6受体的鸡红细胞.表明该毒株具有双受体结合能力。
动物感染试验显示.该毒株对小鼠、1周龄雏鸡、亚成体家鸭均不具有感染力。
结论分离的H16N3毒株为欧亚谱系.对小鼠和家禽无致病性。
该毒株存在结合人1:呼吸道流感病毒受体的能力.但尚未获得感染家禽和哺乳动物的能力•应持续监测.追踪病毒进化待征°关键词】禽流感病馭H16N3；遗传进化；致病性；受体结合待性；感染能力中图分类号】S852.65【文献标识码】【文章编号】1673-5234(2020)12-1370-07[Journal of Pathogen Biology.2020Dec；15(12):1370—1376.]A genetic evolutionary analysis and an evaluation of the infectivity of avian influenza H16N3isolated fromwild birds in ChinaSUN Lei-yun1'・LI Yuan-guo,ZHANG Xing-hai2',ZHAO Meng-lin・HU Xin—yu,WANG Tie-cheng J,SUN Wei-yang・FENG Na2・ZHAO Yong-kun~・YANG Song-tao2•XIA Xian-zhu2,MENG De~R o n g1,GAO Y u-wei~(1.College of Alli mal Science and Technology・Jilin Agricultural University»Changchun9China130118； 2.Institute of Military Veterinary Medicine.Academy of Military Medical Science； 3.J ilin University; 4.Can^zhou Normal University)Objectives To ascertain the genetic evolutionary characteristics and biological characteristics of the H16N3 subtype of the avian influenza virus in order to provide a scientific basis for early warning of avian influenza virus from wild birds.Methods Fecal samples from wild birds in major migratory bird habitats in central and eastern China were collected and inoculated into SPF chicken embryos after treatment to obtain pathogens with blood agglutination characteristics.and the virus subtypes were determined using whole gene sequencing.A phylogenetic tree was constructed for the H16subtype of the influenza virus.and the subtypes were characterized molecularly.The receptor binding characteristics of the virus were determined and infection tests were conducted in mice and poultry to evaluate the pathogenicity of the virus to mammals and poultry.Results One strain of pathogen(CZ-638)was isolated and identified as avian influenza virus subtype H16N3according to whole genome sequencing and electron microscopy.In the phylogenetic tree・the strain was located in the Eurasian lineage branch.An analysis of amino acid sites indicated that an HA protein cleavage site was INER J GLF.which was in line with the molecular characteristics of the low pathogenic avian influenza virus.Amino acid 228of the receptor binding domain mutated from G(glycine)to S(serine).This strain agglutinated sheep red blood cells・normal chicken red blood cells,and chicken red blood cells with the SAa2,6receptor alone・indicating that this vi-【基金项目】【通讯作者】【作者简介】国家科技重大专项（No.2O2OZX1OOO1-O16-OO3）；国家自然科学基金项目（No.31970502）。
白榆接种外生菌根真菌生长响应的初步研究
山东农业大学学报(自然科学版),2023,54(4):544-552VOL.54NO.42023 Journal of Shandong Agricultural University(Natural Science Edition)doi:10.3969/j.issn.1000-2324.2023.04.010白榆接种外生菌根真菌生长响应的初步研究韩凤旗,闫伟*内蒙古农业大学林学院,内蒙古呼和浩特010018摘要:为探索白榆(Ulmus pumila)对外生菌根真菌的侵染响应，本文以白榆为宿主树种，选取3种外生菌根真菌褐环乳牛肝菌(Suillus luteus)、点柄乳牛肝菌(S.granulatus)与粘盖乳牛肝菌(S.bovinus)进行了人工菌根合成、光合及生长效应等内容的初步研究，试验用幼苗由种子萌发，分别采用固体和液体二种菌剂进行接种处理，接种后在高智能光照室持续培育90d。
接种幼苗高生长、总叶绿素含量、干旱胁迫下接种幼苗高生长效应与未接菌的幼苗指标差异显著（P<0.05）,白榆接种处理净光合速率（Pn）、光化学淬灭系数(qP)、最大光化学效率(Fv/Fm)对照CK始终明显低于3个接种处理，非光化学淬灭系数(NPQ)对照CK始终明显高于3个接种处理。
由此从光合基础上证实了对幼苗接种有助于提高其适应性和抗逆性。
关键词:白榆;共生菌;侵染响应中图法分类号:S714文献标识码:A文章编号:1000-2324(2023)04-0544-09 Preliminary Study on the Growth Response of Ulmus pumilaInoculated with Ectotrophic Mycorrhizal FungiHAN Feng-qi,YAN Wei*Forestry College of Innet Mongolia Agricultural University,Hohhot010018,ChinaAbstract:To explore the response of Ulmus pumila to exogenous mycorrhizal fungi,taking U.pumila as host species,three ectomycorrhizal fungi,Suillus luteus,S.granulatus and S.bovinus,were selected for a preliminary study of artificial mycorrhizal synthesis,photosynthesis and growth effects.The experimental seedlings were germinated from seeds and inoculated with solid and liquid inoculants respectively.After inoculation,the seedlings were incubated in a high-intelligent light room for90days.Results showed that high growth,total chlorophyll content and high growth effect of inoculated seedlings under drought stress were significantly different from those of uninoculated seedlings(P<0.05).Net photosynthetic rate(Pn),photochemical quenching coefficient(qP)and maximum photochemical efficiency(Fv/Fm)of inoculated white ulmus were significantly lower than those of inoculated control CK.The non-photochemical quenching coefficient(NPQ)of CK was always significantly higher than that of the three inoculated treatments.It was proved that inoculation could improve the adaptability and stress resistance of seedlings on the basis of photosynthesis.Keywords:Ulmus pumila;symbiotic bacteria;infection response白榆（Ulmus pumila）是榆科（Ulmaceae）榆属（Ulmus）乔木树种，喜光，耐旱，耐寒，耐瘠薄，抗逆性、适应性超强。
青稞B hordein基因对小麦面粉加工特性的影响
青稞B hordein基因对小麦面粉加工特性的影响青稞B hordein基因是小麦谷物中一种重要的蛋白质，它对小麦面粉加工特性有着重要的影响。
近年来，大量研究表明青稞B hordein基因是一种多态的蛋白质，它可能控制小麦对于湿度和温度的反应，以及小麦面粉的加工性能。
例如，阿拉伯人研究发现，hordein基因突变可以改变小麦的耐湿性，从而改变其在弱碱新面糊中的加工性能。
此外，泰勒和詹姆森在1979年得出结论，hordein突变会改变小麦混合物的稠度和稠率，从而影响其加工特性。
对于青稞B hordein基因对小麦面粉加工特性的影响，目前还缺乏全面的、系统的研究。
因此，有必要进行深入研究，以弄清青稞B hordein基因突变对小麦面粉加工特性的影响，并建立科学有效的小麦面粉加工配方以满足市场的需求。
在研究小麦加工特性时，还应该考虑其他因素，例如添加剂、水分以及处理过程影响等。
最近的研究揭示了不同省份小麦品种之间存在着明显的基因多样性，并且这种基因多样性会对小麦面粉的加工性能产生重大影响。
因此，在制定面粉加工配方时，应考虑新的基因或调节因子，以改善小麦加工特性。
此外，为了更好地理解青稞B hordein基因对小麦面粉加工特性的影响，还应研究小麦-青稞B hordein的作用机制，并开发出能够有效控制小麦加工性能的技术。
这将不仅有助于提升小麦产品的品质，而且还将更好地改善小麦面粉加工过程所面临的风险和限制。
总之，青稞B hordein基因对小麦加工特性的影响是一个复杂的话题，研究有待更深入。
在研究小麦加工特性的同时，应该考虑其他因素，例如酵母等微生物的作用。
通过酵母发酵可以改变小麦面团的口感和结构，从而影响小麦面粉加工特性。
此外，对小麦化学成分的研究也有助于提升小麦面粉加工特性，因为不同的化学成分可能会改变小麦糊状性、流变性等加工特性。
未来研究也可以专注于青稞B hordein基因通过不同信号通路影响小麦加工特性的方式。
紫外吸收剂插层蒙脱土对沥青老化性能的影响
建筑材料学报JOURNAL OF BUILDING MATERIALS第24卷第2期2021年4月Vol. 24,No. 2Apr. ,2021文章编号；1007-9629(2021)02-0362-08紫外吸收剂插层蒙脱土对沥青老化性能的影响冯振刚，张沛，孙思敖，栗培龙，李新军(长安大学公路学院，陕西西安710064)摘要：采用有机插层剂对钠基蒙脱土进行有机化处理，得到有机蒙脱土(OMMT),分别将其与不同类 型的紫外吸收剂(UVA)进行复合插层，制备得到UVA 插层OMMT,并通过X 射线衍射试验对UVA 插层OMMT 的结构进行了表征；同时通过熔融共混法，制备了 UVA 插层OMMT 改性沥青，并采用常规性能试验、薄膜烘箱老化试验和紫外光(UV)老化试验,研究了 UVA.插层OMMT 改性沥青的物理性能、耐热氧老化性能和耐UV 老化性能，评价了不同类型UVA 插层OMMT 对沥青耐老化性能的影响.结果表明：不同类型UVA.插层OMMT 对沥青的耐热氧老化性能和耐UV 老化性能均具有 改善作用，其中UV328插层OMMT 改性沥青和UV326插层OMMT 改性沥青的耐老化性能较优，原因一是OMMT 的片层结构阻止了热和氧向沥青内部扩散，原因二是UV328插层OMMT 和UV326 插层OMMT 具有较大的插层率，从而增强了 UVA 插层OMMT 对紫外光屏蔽与吸收的协同作用.关键词：沥青；紫外吸收剂；蒙脱土；热氧老化；紫外光老化中图分类号:U414文献标志码：A doi ；10. 3969/j. issn. 1007-9629. 2021. 02. 019Effect of Ultraviolet Absorber Intercalated Montmorilloniteon Aging Properties of AsphaltFENG Zhengang, ZHANG Pei, SUN Siao f LI Peilong, LI Xinjun(School of Highway, Chang*an University, Xi'an 710064, China)Abstract : The organic montmorillonite (OMMT) was obtained via intercalation of Na-montmorillonite by organic intercalator. Then the ultraviolet absorber(UVA)intercalated OMMT was prepared with differenttypes of UVA and OMMT. The structure of UVA intercalated OMMT was characterized by X-ray diffrac tion (XRD) test. The UVA intercalated OMMT modified asphalt was prepared via melt blending. The physical properties, thermo-oxidative aging resistance and ultraviolet (UV ) aging resistance of the UVAintercalated OMMT modified asphalt were investigated by conventional physical properties test, thin filmoven test(TFOT) and UV aging test, respectively. Based on these, the effect of different types of UVA intercalated OMMT on aging resistance of asphalt was evaluated. The results show that both the thermo-oxidative and UV aging resistance of asphalt can be improved by the UVA intercalated OMMT, amongwhich the UV328 intercalated OMMT modified asphalt and UV326 intercalated OMMT modified asphaltshow better aging resistance. The reason is that the layered structure of OMMT prevents heat and oxygenfrom diffusing into the asphalt. On the other hand, the intercalation rate of UV328 intercalated OMMTand UV326 intercalated OMMT is larger, which enhances the synergistic effect on shielding and absorbingUV light of the UVA intercalated OMMT.Key words : bitumen; ultraviolet absorber; montmorillonite ; thermo-oxidative aging ; ultraviolet aging收稿日期：2020-02-29；修订日期：2020-04-05基金项目:国家自然科学基金资助项目(51508032);吉林省交通运输科技项目(2018-1-7);山西省公路局科技项目(2019-1-2);中央高校基本科研业务费资助项目(300102219216)第一作者:冯振刚(1986-),男，河南三门峡人，长安大学副教授，硕士生导师，博士. E-mail ：Z gfeng@chd. edu. cn第2期冯振刚，等:紫外吸收剂插层蒙脱土对沥青老化性能的影响363沥青老化主要包括热氧老化和紫外光（UV）老化两方面，前者根据老化发生的时间和条件不同分为短期热氧老化和长期热氧老化，后者发生在沥青路面服役期间，是一种长期的光氧老化过程2」.随着长寿命沥青路面的推广应用，沥青的UV老化受到了广泛关注，对于沥青抗UV老化措施的研究也已成为国内外的研究热点⑷.目前，常用的方法是将具有吸收紫外光或屏蔽紫外光功能的改性剂（如紫外吸收剂、层状硅酸盐等）掺加到沥青当中，以改善沥青的耐UV老化性能2」.前期研究表明，部分紫外吸收剂（UVA）可在不影响沥青自身化学结构的情况下改善沥青的耐UV 老化性能，同时发现UVA对沥青的低温性能也具有显著的改善作用⑷•不同类型的UVA在某一合适掺量下不仅可改善沥青的耐UV老化性能，而且能提高沥青的耐热氧老化性能页•此外，将蒙脱土（MMT）有机化处理后可以改善蒙脱土与沥青的相容性，提高有机蒙脱土（OMMT）改性沥青的耐老化性能口〉⑷.虽然单独掺加UVA或OMMT可改善沥青的耐老化性能，但OMMT的加入会使沥青的低温性能明显下降,而一些UVA的热稳定性较差，在制备改性沥青的过程中容易受热失效，起不到应有的改性效果E8'15-16].鉴于此，本文基于OMMT可赋予层间插层物质热稳定性和改善沥青耐老化性能的作用，以及UVA对沥青耐UV老化和低温性能的改善作用，采用4类UVA（UV326、UV328、UV531、UV770）与OMMT进行复合插层，制备了4类UVA插层OMMT,并通过X射线衍射（XRD）分析了不同类型UVA插层OMMT的结构；同时通过熔融共混法，制备了4类UVA插层OMMT改性沥青，并采用常规性能试验、薄膜烘箱老化试验（TFOT）和UV老化试验，研究了UVA插层OMMT改性沥青的物理性能、耐热氧老化性能和耐UV老化性能，评价了不同类型UVA插层OMMT对沥青耐老化性能的影响.1试验过程1.1原材料壳牌90#基质沥青、钠基蒙脱土（Na-MMT）、有机插层剂（十八烷基二甲基节基氯化鞍）、紫外吸收剂（UV326、UV328、UV531、UV770）;原材料的技术指标见表1~4.1.2UVA插层OMMT的制备（1）取15g Na-MMT与300mL蒸憎水配制成表1壳牌90*沥青的技术指标Table1Technical specification of Shell90#asphaltItem SpecificationPenetration(25°C,5s,100g)/(0.1mm)90 Ductility(5cm•min-1,15°C)/cm>100Softening point/°C45.9Density(15°C)/(g•cm-3) 1.034Mass loss ratio/%—0.065 RTFOT Penetration retention61.2 (163 85min)ratio(25C)/%Residual ductility(15C)/cm47.3表2Na-MMT的技术指标Table2Technical specification of Na-MMTItem SpecificationColor Creamy-whiteGranularity/mm0.075 Montmorillonite content(by mass)/%$95 Cation exchange capacity/mmol0.9/100gAverage wafer thickness/nm25Density/(g•cm-3) 1.9Apparent viscosity/(mPa・s)5000pH value&0Whiteness/%75表3十八烷基二甲基莱基氯化镀的技术指标Table3Technical specification of octadecyl dimethyl benzylammonium chlorideItem SpecificationAppearanceColorless to light yellowtransparent liquidCH3Cl~Molecular formula CH2—N+—CH2(CH2)16CH:1Relative molecular mass424.15Purity(by mass)/%50CAS number122-19-0Active matter content(by mass)/%50±1Free amine content(by mass)/%<2.0pH value(259,1%) 6.0-8.0溶液，室温下以1200r/min的速率搅拌1h,使Na-MMT形成分散悬浮液；（2）采用水浴恒温装置，使温度保持在80°C,然后将6.87g的十八烷基二甲基节基氯化鞍加入到Na-MMT悬浮液中，并以1200r/min的速率搅拌2h,得到有机蒙脱土（OM-MT）溶液；（3）按UVA插层OMMT总质量的30%将不同类型的UVA加入到OMMT溶液中，继续在364建筑材料学报第24卷表4不同类型UVA的技术指标Table4Technical specification of different types of UVAType Appearance Content(by MeltingTransmittance/%mass)/%point/°C450nm500nmUV326Light yellow crystalline powder>9970-72>97>98 UV328Light yellow powder>99>81>97>98 UV531Light yellow needle powder>9947-49>90>95 UV770Colorless or slightly yellow crystalline powder>99>141>98>99相同条件下反应2h后停止加热与搅拌，自然冷却至室温，然后将得到的絮状沉淀物反复洗涤，并在100°C条件下干燥至恒重，研磨成粉末，即得到不同类型的UVA插层OMMT.1.3UVA插层OMMT改性沥青的制备将不同类型的UVA插层OMMT与基质沥青通过熔融共混的方法制备UVA插层OMMT改性沥青•将基质沥青加热至150°C，然后将不同类型的UVA插层OMMT按不同掺量(占基质沥青质量的1%、2%、3%、4%)加入到基质沥青中，采用高速剪切乳化机在150°C、1800r/min条件下剪切0.5h,以确保UVA插层OMMT在沥青中分散均匀.为了便于对比，OMMT改性沥青也采用相同方法进行处理.1.4UVA插层OMMT的X射线衍射(XRD)分析采用Ultimate IV型X射线衍射仪对UVA插层OMMT的结构进行表征.XRD测试条件如下:&射线(波长为0.15406nm).Cu靶、辐射管电流为30mA、辐射管电压为40kV,扫描范围0.5°〜10.0°,频率采用l(°)/min,扫描方式为连续记谱扫描方式.1.5UVA插层OMMT改性沥青的物理性能试验按照JTG E20-201H公路工程沥青及沥青混合料试验规程》中T0604、T0605、T0606和T0625的规定，测试改性沥青的针入度、延度、软化点和黏度.1.6UVA插层OMMT改性沥青的老化试验(1)TFOT老化试验：按照JTG E20—2011中T0609的规定，模拟UVA插层OMMT改性沥青的短期热氧老化过程.TFOT老化试验的温度为163°C,老化时间为5h.(2)U V老化试验:通过室内加速紫外光老化箱来模拟UVA插层OMMT改性沥青的UV老化过程.试验过程如下：将经过TFOT老化后的沥青试样移至紫外光老化箱中进行UV老化，UV波长范围为300〜360nm,UV灯泡功率为300W,试验温度为60°C,老化时间为144h.2结果与讨论2.1UVA插层OMMT的XRD分析不同类型UVA插层OMMT的XRD测试结果如图1所示.由图1可见：采用有机插层剂对Na-MMT进行有机化处理后，所得到的有机蒙脱土(OMMT)衍射角向小角度移动；不同类型UVA与OMMT插层后，其衍射角进一步向小角度移动，表明Na-MMT经有机化处理后其层间距均有所增大•这是因为Na-MMT具有片层状结构，经有机化处理后，相对分子质量较大的基团置换了原有的层间阳离子，从而使得其层间距显著扩大刀.基于XRD图谱,在已知入射角9的情况下，通过布拉格(Bragg)方程可以计算得到UVA插层OMMT的层间距，见式(1).2〃ooisin0=m(1)式中：弘。
美国宾夕法尼亚州大学研究人员采用纳米纤维复合材料创建生物基材料
美国宾夕法尼亚州大学研究人员采用纳米纤维复合材料创建生
物基材料
佚名
【期刊名称】《高科技纤维与应用》
【年(卷),期】2012(037)006
【摘要】位于美国宾夕法尼亚州费城的宾夕法尼亚州大学（Penn）于2012年8月7日报道，该校研究人员已开发和验证一种技术，采用纳米纤维复合材料作为组织支架，相当于再生的筋、韧带和半月板组织，用在受伤病人的膝盖、肩袖（肌键袖）、跟键及其他关节上。
【总页数】2页(P74-75)
【正文语种】中文
【中图分类】TQ342.94
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a r X i v :c ond-ma t/997362v1[c ond-m at.str-el]23J ul1999Magnon Broadening Effects in Double Layered Man-ganite La 1.2Sr 1.8Mn 2O 7Nobuo Furukawa a ,Kazuma Hirota b a Department of Physics,Aoyama Gakuin University,Setagaya,Tokyo 157-8572,Japan b CREST,Department of Physics,Tohoku University,Sendai 980-8578,Japan Abstract:Magnon linewidth of La 1.2Sr 1.8Mn 2O 7near the Brillouin zone boundary is investigated from both theoretical and experimental points of view.Abrupt magnon broadening is ascribed to a strong magnon-phonon coupling.Magnon broadening observed in cubic perovskite manganites is also discussed.1Introduction Magnetic excitation spectra of colossal magnetoresistance (CMR)manganites in the ferromagnetic metal phase attract our attention in the point whether they can be understood by the conventional double-exchange (DE)mech-anism.For (La,Sr)MnO 3and (La,Pb)MnO 3where T c is relatively high,a cosine-band type magnon dispersion is observed [1,2,3].At low tempera-ture,Magnon linewidth Γis narrow enough throughout the Brillouin zone,which makes it possible to observe well-defined magnon branches,and it be-comes broad at finite temperature.The DE model explains the cosine-band dispersion [4]as well as the temperature dependence of the linewidth in the form Γ∝(1−M 2)ωq ,where M is the magnetization normalized by the sat-uration value and ωq is the magnon dispersion [5].The origin of the magnon broadening is the Stoner absorption,which disappears at T →0(or M →1)due to the half-metallic nature of the system.For compounds with lower T c ,Doloc et al.[6]observed broadening ofmagnon dispersion.They claimed that the abrupt increase of linewidth near the zone boundary can not be explained by DE mechanism alone.One of the possible explanations is that the broadening is caused by the magnon-phonon1interaction[7].A strong coupling between magnons and phonons are through the modulation of the exchange coupling by the lattice displacement.Anomalous broadening of magnon linewidth is also observed in the double-layered manganite La1.2Sr1.8Mn2O7[8].Intra double-layer coupling creates optical and acoustic branches of magnons.Two-dimensional dispersion of both branches indicates that the inter double-layer coupling is sufficiently weak.Magnon broadening near the zone boundary is also observed in this compound.In this paper we investigate the possibility of this broadening caused by the magnon-phonon interaction.2Comparison between theory and experimentAs for dispersionless optical phonon with frequencyΩ0,the magnon linewidth due to magnon-phonon interaction is given byΓ(q)∝D(ωq−Ω0),where D(ω) is the magnon density of states[7].In a two dimensional system,we have step-function like behavior.(1)Γ(q)= Γ0ωq>Ω00ωq<Ω0When a magnon with momentum q has energyωq>Ω0,it is possible tofind an elastic channel to decay into a magnon-phonon pair with momentum q′and q−q′,respectively,which satisfiesωq=ωq′+Ω0.This is the reason why magnon linewidth abruptly becomes broad as magnon branch crosses that of the phonon.Let us now compare the theoretical results with experimental data.We show inelastic neutron scattering intensities for La1.2Sr1.8Mn2O7in Fig.1, where a contour map is plotted in theω-q plane.Scattering vector is taken as(1+q,0,5)in the reciprocal lattice units.Details of experimental are given in ref.[8].A well-defined acoustic magnon branch is observed near the zone center.We also see optical phonon which is nearly dispersionless atω∼20meV.Above q∼0.3where magnon branch and phonon branch crosses,we see an abrupt increase of the magnon linewidth.A weak trace of the dispersion is observed above the crossing point.The data is consistently explained as follows.Magnon dispersion is cosine-band like with the zone boundary energy∼40meV,which crosses with the optical phonon withΩ0∼20meV.A strong coupling between magnons and phonons creates abrupt magnon broadening above the crossing point.23DiscussionMagnon dispersions so far observed in the ferromagnetic metal phase of man-ganites are well defined near the zone center regardless of compounds and dimensionalities.Zone boundary broadening is,however,strongly compound dependent.The present result suggests that the zone-boundary magnon broadening is influenced by the strength of the magnon-phonon interac-tions.Although magnon-phonon dispersion crossing is also reported in three-dimensional manganites[3,9],zone-boundary broadening is observed only in low T c compounds.This implies a relation between T c and spin-lattice inter-action strength.Strong damping of the zone-boundary magnons might also explain the“zone-boundary softening”of magnons in low T c manganites[10], if we assume that the zone-boundaryflat dispersion observed by neutron in-elastic scattering is allocated as an optical phonon branch,while the real zone-boundary magnon branch at higher frequency is wiped out above the magnon-phonon crossing point.Further detailed studies of the relations between the magnon linewidth broadening above the magnon-phonon crossing point and the other magneto-elastic behaviors will clarify the role of the spin-lattice interactions to various physical properties.N.F.thanks J.Fernandez-Baca for discussion.K.H.acknowledges H.Fu-jioka,M.Kubota,H.Yoshizawa,Y.Moritomo and Y.Endoh for experimental collaborations.This work is partially supported by Mombusho Grant-in-Aid for Priority Area.References[1]T.G.Perring,G.Aeppli,S.M.Hayden,S.A.Carter,J.P.Remeikaand S.-W.Cheong,Phys.Rev.Lett.77(1996)711.[2]M.Martin,G.Shirane,Y.Endoh,K.Hirota,Y.Moritomo and Y.Tokura,Phys.Rev.B53(1996)14285.[3]A.Moudden,L.Vasiliu-Doloc,L.Pinsard and A.Revcolevschi,PhysicaB241-243(1998)276.[4]N.Furukawa,J.Phys.Soc.Jpn.65(1996)1174.3[5]N.Furukawa and K.Hirota,Physica B241-243(1998)780.[6]L.Vasiliu-Doloc,J.W.Lynn,A.H.Moudden,A.M.de Leon-Guevaraand A.Revcolevschi,Phys.Rev.B58(1998)14913.[7]N.Furukawa,J.Phys.Soc.Jpn.68(in press,cond-mat/9905133).[8]H.Fujioka,M.Kubota,K.Hirota,H.Yoshizawa,Y.Moritomo and Y.Endoh,J.Phys.Chem.Solids(in press,condmat/9902253).[9]P.Dai,H.Hwang,J.Zhang,J.Fernandez-Baca,S.-W.Cheong,C.Kloc,Y.Tomioka and Y.Tokura,cond-mat/9904372.[10]H.Hwang,P.Dai,S.-W.Cheong,G.Aeppli,D.A.Tennant and H.A.Mook,Phys.Rev.Lett.80(1998)1316.Figure captions.Figure1:The dispersion relation of acoustic branch of spin wave of La1.2Sr1.8Mn2O7 at10K(I4/mmm:a=3.87˚A,c=20.1˚A).Measurements were carried out on the triple-axis spectrometer TOPAN located in the JRR-3M reactor of JAERI.PG(002)reflection of pyrolytic graphite was use to monochromate and analyze neutrons.Data were taken at every1meV and0.05rlu(re-ciprocal lattic unit)along(1+q05)and accumulated for7min.Contours are drawn every20counts between0and400.Nearly dispersionless optical phonon branch is also observed atω∼20meV.4This figure "l327.jpg" is available in "jpg" format from: /ps/cond-mat/9907362v1。