法医硅藻检验的历程和最新进展

法医硅藻检验的历程和最新进展| Diatom Identification and its progress in Forensics
硅藻是一种在可在任何自然水域中找到的藻类微生物，因为硅藻具有明显的地域特征以及良好的化学稳定性，所以被认为是法医鉴定中推断溺亡原因和溺亡地点的重要判据。

由于水体中的硅藻通常都是微米级的，故最合适的方法是采用显微放大的方式进行观测，把制备好的样品转移至滤膜上再置于显微镜下观测比较。

Diatom is a kind of microorganism that could be found in any natural water. Because of the territorial character and chemical stability, diatom is used in forensic identification to deduce the reason of drowning and the important criterion of drowning location. As the size of diatom in water is usually at the level of micrometer, so the most common method to observe is microscope. By transferring the sample prepared to the filter film the diatoms could be compared and found under microscope.
纵观过去，硅藻的显微分析经历了三个历程，技术更新持续至今。

Till now, microanalysis of diatom has experienced three decades and the technology is continuing up to date.
第一代：光学显微镜| Optical Microscope
光学显微镜观测是最简单的方式。

由于放大倍数和分辨率的限制，只有尺寸较大的藻类能被观测到（10 微米以上），而对肺以外的内脏如肾、肝样品观测效果较差，很容易出现假阴性判断。

It is the simplest way to observe diatom by optical microscope. Due to the restriction of the magnification, only larger than 10 microns diatoms could be observed. It is difficult for the samples from viscera, such as the kidney and liver samples. Thus it is the main reason of false negative judgment.
第二代：扫描电镜法|SEM
这是目前最理想也最常用的一种方法，由于极高的分辨率，SEM可以观测到哪怕是极小（达到甚至小于1微米）的硅藻。

因此可以说所有的藻类都能被观测到，但是由于SEM的视场小，要想对大面积的滤膜进行无遗漏的观测，并对硅藻进行分类和计数，还是相当困难并且耗时的。

因此，这种方法的局限性非常明显。

This is one of the most ideal methods that most commonly used at present. Because of its high resolution, SEM can observe diatoms that are small to less than 1 micron. But the high magnification also brings difficulty to SEM that it is not easy to go through the whole film sample without missing any part of it and it is also time-consuming. Thus the limitation of this method is very clear.
第三代：专用硅藻检验方案|DiatomScope
DiatomScope 是LabWorld公司开发的全新一代快速自动法医硅藻检验系统，是基于飞纳台式扫描电镜进行的开发，目前DiatomScope在以下方面体现了非常实用的价值：
DiatomScope is a new generation of diatom detection solution developed by LabWorld Scientific. It is a development based on the desktop Scanning Electron microscope (SEM). The current DiatomScope has sh own a great of practical value in the following aspects:
1.基于全球最快的台式扫描电镜，取图速度快；
1.based on the fastest desktop scanning electron microscope in the world, the speed of
capturing a picture is very fast.
越来越多的人认为扫描电镜是进行硅藻分析的必要工具，飞纳公司设计的扫描电镜，操作简单，待机时间短，取图速度快，是非常合适的硅藻检验工具。

More and more researchers think that SEM is the right tool for diatom analysis. Since the SEM
manufactured by Phenom is easy to use, the waiting time is very short and the time of capturing image is very fast so it is the best for diatom inspection.
2.自动快速样品扫描，确保无遗漏区域；
2. Automatic and fast whole sample scanning to ensure that no area is missed.
SEM分析硅藻最令人头疼的一点是效率，一般情况下用户需要一个个视场逐个进行观测，记录。

DiatomScope系统设计了简便的操作流程，通过简单快速的培训即可上手操作，且内置算法使得SEM的扫描速度更快；
The most headache point of diatom analysis by SEM is the speed or efficiency. In general, user has to capture the image tile by tile, then record one by one. DiatomScope simplified the
process by programming, which can be operated with a quick and simple training. The built-in algorithm makes the scanning procedure faster.
全样品或自定义扫描区域后，仪器即可自动按设定自动完成所有扫描，确保无遗漏，而且一次最多可以放置9个1英寸样品，设置好后仪器还可以自动夜间工作。

另外扫描和硅藻确认分析可分开独立进行，这样仪器的使用效率得以提高；
After defining the whole sample or customized area, the instrument can automatically complete all the scans automatically according to the set, ensure no omission, and can place up to 9 1-
inch samples at most, and the instrument can also work at night automatically. Besides,
scanning and diatom recognition analysis can be carried out separately and independently, thus it improves the efficiency of the instrument.
3.可协同工作，节省占机时间；
3. work corporately to save time
样品扫描后，条件许可的用户可以通过软件并行工作共同进行硅藻标记工作，系统自动对标记的地方进行高放大倍数取图，使用户可以最终进行判定；
On the basis of the results of the whole sample scanning, the user can confirm the diatom
labelling work through the software in parallel, and the system can automatically capture the image on high magnification again, then the user can finally make a decision.
4.自动统计硅藻种类和数量并生成报告；
4.Automatically count diatom species and quantities and generate reports.
结合大量的用户体验设计的自动生成报告功能减少了用户工作，直观地呈现出统计数据和细节，便于法医做出判断。

Combined with a large number of user experience, automatically generated reports reduce user work, intuitionistic presentation of statistical data and details, making it easier for forensic
police to make the right judgment.
在此基础上，LabWorld将致力于开发更智能化的硅藻检验方法，持续报道将在后续登出。

Based on the above, Labworld will devote to develop more automatic identification method in the future, it will be reported continually with your attention.。