微波辐射固定及其在免疫金标记技术中的应用

应用微波辐射快速固定大鼠胰腺组织和白血病病人骨髓细胞悬液,再按常规制作电镜超薄切片。包埋后超薄切片免疫金标记β细胞中的胰岛素分泌颗粒显示组织细胞结构清晰,标记率高,(图1)。骨髓细胞悬液包埋前免疫金标记和酶反应定位血小板表面糖蛋白(GPⅡb/Ⅲa)和胞浆内过氧化物酶均呈现阳性结果(图2)。电镜观察结果表明,经微波辐射固定的生物样品能较好地保存细胞的超微结构,抗原性及其酶活性。根据多次反复试验,我们取得的经验是,在进行微波辐射固定生物样品时,电镜样品固定温度和时间以26～28℃,15秒为宜。由于微波辐射加热温度升高很快,我们采用在炉室内四角放置四个盛有     

类果蝇复眼视觉神经计算建模及仿生应用研究综述

随着类果蝇复眼视觉神经计算建模技术的快速发展,如何提高运动目标的实时检测追踪等仿生应用能力成为类果蝇复眼视觉神经领域的研究难题,所以研究类果蝇复眼视觉神经计算建模及其仿生应用具有非常重要的意义。类果蝇复眼视觉神经系统是一个高度平行的专用视觉神经网络模型,并具有适度的复杂性以允许快速进行视觉信息处理。本文首先从类果蝇复眼的生理结构、感光细胞的光电转换、视叶神经的加工处理、中央脑的认知抉择4个部分详细阐述类果蝇复眼视觉神经计算建模的研究现状,然后介绍类果蝇复眼视觉神经计算建模在军事与民用领域的典型仿生应用,最后展望了类果蝇复眼视觉神经计算建模的发展趋势与挑战。     

盖玻片在培养细胞免疫电子显微术中的应用

体外培养的细胞不仅可用于研究其形态和机能的变化,而且可进行不同药物学作用时细胞内抗原成分的定位检测及细胞特征的研究。通常盖玻片放入培养皿中作为培养细胞的支持物,细胞在盖玻片上长成单层,可立即固定、染色,进行光学显微镜的观察。在实验中我们发现,加盖玻片的单层细胞培养法也可以直接应用于免疫电镜的包埋前和包埋后染色方法。该技术具有以下优点。(1)使用盖玻片可以避免免疫电镜标本制作过程中,为了搜集细胞而进行的数次刮取、离心。免疫反应及后固定、脱水、浸透、包埋均在盖玻片上进行,使培养细胞的损伤降低至最小程度。(2)如果在直径3．5cm的培养皿中进行免疫过氧化物酶反应大约需要至少200μl抗体,而使用盖玻片法,每张盖玻片则仅需要10μl抗体,大大节约了免疫反应的抗体量,既简便又经济。(3)盖玻片法使包埋后培养细胞呈单层位于包埋块的表面,在每一张超薄切片中都能观察到很多细胞。     

电镜包埋块快速制备中污染物的实验观察

临床诊断电镜工作的开展 ,必然要求改变以往周期长的制样过程 ,而包埋块制备过程所花时间最多 ,人们用微波聚合、高温聚合等条件以缩短聚合时间 ,并在实际工作中得以应用 [1]。但常为了快速 ,而在样品固定到包埋前的处理中忽视了某些细节 ,造成包埋块制备中的人为污染 ,影响电镜观察 ,这些污染无法通过返工来弥补。本文就此污染物产生进行模拟实验与探讨。材料与方法正常小鼠乙醚麻醉后 ,快速取肾组织入 3%戊二醛 - 1 .5 %多聚甲醛的前固定液中 ,后固定液用 1 %锇酸 - 1 .5 %亚铁氰化钾 ( 1∶ 1 ) ,70 %酒精饱和铀液块染过夜 ,系列酒精、丙…     

百日草木质化过程的研究

管胞的分化常被作为细胞分化的模型(1)。早先,曾用酸性磷酶为标示,做过水稻发育的研究(2,3)。本篇报告注重在百日草木质化过程中细胞超微细结构的变化及酸性磷酸酶在细胞中分布情形的探讨。由百日草叶诱道出的愈合组织,生长在分化培养基中。取出愈合组织做成二醛及锇酸之双重固定,用洒精脱水,再包埋於低粘度树脂中,切完片,经醋酸铀及柠檬酸铅染色,在电显下观察。细胞化学法则利用高模理氏(Gomori’S)反应,在前固定后处理(4)。     

一种观察体内细胞骨架的电镜方法

迄今为止对细胞骨架的形态与分布的研究,几乎全部是在组织培养细胞中进行的。这主要是由于研究活体组织中细胞时要进行切片,而引入的包埋介质限制了去垢剂进行提取等重要而有效的技术手段的应用。然而,有关的研究结果已充分显示出体外人工培养条件,特别是对固体基质表面的附着,造成了骨架系统的一系列显著改变。本文试用新鲜活体组织为材料,在Bright5030型低温切片机上快速冷冻并切成2—8μ厚切片,用盖玻片条或电镜载网取下切片,立即放入37℃的含有非离子型去垢剂TritonX—100(浓度为0.5％)和戊二醛(浓度为2％)的微管稳定性缓冲液中进行处理,或先行提取随之进行固定。用系列提高浓度的乙醇脱水后,临界点干燥,喷镀金膜,用扫描电镜观察,或在固定后用醋酸双氧铀染色。再经脱水和临界点干燥,以透射电镜观察。从而提供了一     

适合光镜和电镜诊断肾小球疾病的固定剂选择

目的：为了使已经石蜡包埋的肾穿组织脱蜡后进行电镜观察,关键是选择适当的固定剂。方法：在石蜡包埋前,肾穿组织分别用甲醛、戊二醛及戊二醛、锇酸双固定。根据光镜和电镜观察结果,选择能兼顾光镜和电镜的固定剂。结果：甲醛固定不能有效保存肾穿组织的超微结构,锇酸的固定能有效地保存超微结构,但严重影响了光镜切片的染色;而戊二醛与甲醛相比,较好地保存了肾穿组织的超微结构,同时又不影响光镜切片的染色。结论：在石蜡包     

卫星广播调度的鲁棒生长方法

本文提出基于果蝇刚毛分化自组织机理的卫星广播调度新方法，该方法生长出了这种问题的优化解。为增加自组织计算的鲁棒性引入了随机竞争排序技术，对不同大小问题的计算测试表明该方法能快速一致地产生有好的结果。     

显微摄影测光表测量Epon薄切片的厚度

本文利用显微摄影测光表测量经锇酸固定的组织Ｅｐｏｎ薄切片的透光率，将测量过透光率的Ｅ－ｐｏｎ薄切片作重包埋切片确定其厚度。结果显示，Ｅｐｏｎ薄切片的透光率与其厚度之间具有非常好的直线关系。因此，显微摄影测光表能测量经锇酸固定的组织Ｅｐｏｎ薄切片的厚度，而且该切片仍能用于组织细胞形态和化学成份的定量分析以及组织细胞形态的三维重建。     

免疫金法与ABC法在电镜包埋前染色之比较

包埋后免疫电镜术虽能精确定位抗原,但难度大。本文用胶体金标记法与ABC法对人鼻中线恶网瘤组织在树脂包埋前作抗人T细胞免疫染色,并对两种方法进行比较。简述如下:临床活检鼻中线恶网组织,经4％多聚甲醛加1％戊二醛4℃固定,振动切片(50μm),PBS冲洗,在预先硅化的载玻片上作免疫染色:鼠抗人T细胞McAb(Dako公司出品)孵育过夜;金标羊抗鼠抗体(10nm,军科院基础所出品)室温下孵育1小时,再将切片倾入小瓶,经1％锇酸后固定,常规脱水包埋及超薄切片,不作铀铅复     

Cross-dataset emotion recognition from facial expressions through convolutional neural networks

The face is the window to the soul. This is what the 19th-century French doctor Duchenne de Boulogne thought. Using electric shocks to stimulate muscular contractions and induce bizarre-looking expressions, he wanted to understand how muscles produce facial expressions and reveal the most hidden human emotions. Two centuries later, this research field remains very active. We see automatic systems for recognizing emotion and facial expression being applied in medicine, security and surveillance systems, advertising and marketing, among others. However, there are still fundamental questions that scientists are trying to answer when analyzing a person’s emotional state from their facial expressions. Is it possible to reliably infer someone’s internal state based only on their facial muscles’ movements? Is there a universal facial setting to express basic emotions such as anger, disgust, fear, happiness, sadness, and surprise? In this research, we seek to address some of these questions through convolutional neural networks. Unlike most studies in the prior art, we are particularly interested in examining whether characteristics learned from one group of people can be generalized to predict another’s emotions successfully. In this sense, we adopt a cross-dataset evaluation protocol to assess the performance of the proposed methods. Our baseline is a custom-tailored model initially used in face recognition to categorize emotion. By applying data visualization techniques, we improve our baseline model, deriving two other methods. The first method aims to direct the network’s attention to regions of the face considered important in the literature but ignored by the baseline model, using patches to hide random parts of the facial image so that the network can learn discriminative characteristics in different regions. The second method explores a loss function that generates data representations in high-dimensional spaces so that examples of the same emotion class are close and examples of different classes are distant. Finally, we investigate the complementarity between these two methods, proposing a late-fusion technique that combines their outputs through the multiplication of probabilities. We compare our results to an extensive list of works evaluated in the same adopted datasets. In all of them, when compared to works that followed an intra-dataset protocol, our methods present competitive numbers. Under a cross-dataset protocol, we achieve state-of-the-art results, outperforming even commercial off-the-shelf solutions from well-known tech companies.     

应用于硬盘录像机中的网络EPG技术

电子节目菜单（Electronic Program Guide,EPG）,即电子版的未来节目索引。EPG的主要作用就是用户利用EPG提供的菜单,选择自己喜欢的组播频道,点播自己喜欢的视频节目,在线演唱自己喜欢的歌曲。本设计的目的在于针对现有技术的不足,研制开发一种可以通过网络进行节目指南自动下载并存放在刻录机中的新型EPG系统,即电子节目菜单,内容包括未来节目索引,节目信息介绍（节目导演、演员和基本剧情等）,还可通过对节目名称、演员名称、剧种、热点节目等信息对节目进行快速搜索进而实现预制刻录。本设计的特点在于通过网络连接服务器下载EPG,快捷和可实现实时通讯,另可通过EPG显示的节目名称对未来节目进行预制刻录。     

地面雷达抗箔条干扰技术研究

箔条是一种重要且有效的无源干扰方式。箔条弹投放之后,其速度下降较慢,雷达截面积迅速变大,此时箔条信号幅度远大于目标机的,而两者在相同的距离门内,导致可能无法检测到目标机信号。本文基于地面雷达系统,提出了在跟踪帧和搜索帧同时使用自适应动目标显示,实现飞机和箔条信号的频域分离;根据含有多普勒频率的线性调频信号经过脉冲压缩处理后峰值点发生偏移的特点,提出了使用大时宽带宽比的线性调频信号,实现飞机和箔条信号的时域分离。进行了雷达信号级仿真实验,结果表明本文提出的措施具有较好的抗箔条干扰能力, 可以快速而正确的获得目标机信号。      

Functions and roles of social media in media transformation in China: A case study of “@CCTV NEWS”

Social media has transformed how traditional media is used and viewed in China. Many traditional media companies are utilizing social media platforms such as WeChat, Weibo (Micro Blog), and Cellphone-Applications to expand their influence. But how has social media contributed to the transformation process of traditional mainstream media in China? Did they push the reform in both deep level and superficial level? We attempts to find the answers by taking CCTV (China’s state media) as the subject of research and explore the social factors that facilitated China’s traditional media’s transformation process, the traditional media’s achievements, as well as the challenges during this period.The paper consists of six parts. In the first part, we had a literature review, and elaborated on terms included in this paper. In the second part, we gave an general introduction to different development periods of CCTV station, CCTV News programs and CCTV’s social media transformation. In the third part, we analyzed the factors that encouraged CCTV to take the strategy of transformation, which are also urging other mainstream media companies in China to take the same steps. In the fourth part, we looked into the achievements the media companies made during the transformation period. Afterwards, the deficiencies and limitations in the transformation process are also analyzed. Finally, we drew conclusions that in the process of transformation, social media plays an important role in superficial reform while attaining very limited achievements in the fundamental level. There is still a long way to go in order to accomplish the all-round integration with new media.The thesis utilizes in-depth interviews, content analysis and literature review as methods of research. It is worth mentioning that this paper is based on first-hand data retrieved from the New Media Department of CCTV News Center.     

Taking back the power: an analysis of Black women’s communicative resistance

Black women are a structurally oppressed group in a subordinate position in the power hierarchy. Language is an important demonstration of group identity and is used to manage the day-to-day realities of being both Black and women. Scholars have devoted attention to explaining why Black women’s discursive practices are a function of their particular vantage point and can serve as a measure of protection against social and political hostilities. While there is a great deal of research acknowledging Black women’s ability to resist, the work can be extended by analyzing the specific resistance strategies Black women employ in common social environments. This essay uses Black/feminist standpoint and power and discourse frameworks to analyze Black women’s communicative resistance across three communication contexts: (1) education, (2) workplace, and (3) personal relationships.     

数字电视气象预警全频道一键式发布系统建设和应用

在全球气候变化的大背景下,气象灾害对人民生命财产安全造成了重大影响。气象预报预警信息能否准确及时地发送到用户,是减轻和避免气象灾害造成损失的重要环节。为此,桐庐县气象局充分利用数字电视网络优势和信息发布快的优势,建成了数字电视气象预警全频道一键式发布系统,为彻底解决农村气象预警信息"最后1 km"问题进行了有益的探索,成为农村地区最有效的气象预警发布手段之一。主要介绍数字电视气象预警全频道一键式发布系统的建设模式、系统功能及应用情况。     

基于语言表达障碍者的藏文语音辅助系统的设计

基于西藏地区语言表达障碍者迫切的实际需要和嵌入式语音播放系统的应用日益成熟和广泛,采用SPCE3200作为本系统的主控芯片,通过TFT LCD模组完成了藏文文本的输入和显示,根据一定算法直接调用存储在外扩Flash(SD卡)上的语音资源,利用SPCE3200自带的解码器,通过软件设计实现了藏文语音播报,旨在帮助广大藏族同胞中语言表达障碍者实现快捷方便有效的与外界的交流。实际使用结果表明,该系统反应速度快,运行稳定,可以直接通过触屏实现藏文的输入和语音播放,简单、快捷、方便。该系统作为藏族同胞语言表达障碍人群的语音辅助工具,极大的方便和改善了他们的生活质量,具有一定的实用推广价值。     

Personalisation — An Overview of its Use and Potential

Some definitions of personalisation are very limited and focus on targeting content at users based on their expressed interests or buying patterns. In BTexact Technologies, considerable effort has been applied to exploring the wider uses of personalisation and how services, tasks, devices, interfaces, etc, can adapt to information in a user profile. It is also important to note that the information in a personal profile need not be static but could change quickly with context. An example of this might be the user's current location. Is personalisation valuable though — or is it just technology hype? Mobile telephones can be used as an example to look at the success factors and, in particular, the value proposition for the user. The reality is that mobile telephones are very personal devices, hold personal contact information, fit into a person's pocket and go everywhere with them. They provide a communications medium for contacting a person rather than a location or an organisation.