不同化学激活剂对小鼠卵母细胞的激活效果

为探讨不同激活剂的卵母细胞孤雌激活效果及激活胚体外发育情况,用乙醇、Ca-A23187、SrCl2、6-DMAP及CB分别对小鼠卵母细胞进行了激活处理。结果显示,70 mL/L乙醇刺激小鼠卵母细胞时,以激活5~7 min的激活效果及孤雌胚发育较好,桑囊胚发育率可达29.11%;用SrCl2激活小鼠卵母细胞时,6~10 mmol/L为最佳处理浓度,3~6 h为最佳激活时间,桑囊胚发育率可达16.67%;以70 mL/L乙醇激活5 min,再用2 mmol/L 6-DMAP 5μg/mL CB激活3 h效果最佳,桑囊胚发育率高达35.77%。研究证实,小鼠卵母细胞经乙醇、6-DMAP和CB等复合激活后能较好地发育。     

关于天津市地方禁毒立法的探索

二十世纪八十年代后,毒品在中国又开始死灰复燃。针对日益严重的毒品违法犯罪,国家制定了一系列法律法规,在禁毒斗争中发挥了巨大作用。但是,由于毒品问题的特殊性和我国国情,仅全国统一禁毒立法还不够,尚需地方立法的细化和补充。本文根据对天津毒品问题的分析和对其他省、市、自治区已有地方禁毒立法的研究比较,指出了制定天津地方禁毒立法的必要性,提出了天津禁毒条例的体系设想,力求为天津的禁毒立法提供某些启示和借鉴,推动我市地方禁毒立法进程。     

From clouds of chemical warfare to blue skies of peace: the Tehran Peace Museum,Iran

Despite the limited number of peace museums around the world, there exists an essential role for existing peace museums to promote a culture of peace and peace education. The purpose of this article was to introduce the origins, rationale, scope and work of the Tehran Peace Museum in Iran. The concept of the museum is to facilitate peace education and develop peaceful environments drawn from the personal experiences of war survivors. The museum encompasses exhibitions about the horrors of chemical and nuclear warfare and is balanced with awareness programmes, bridge-building dialogues, connections with other peace museums and a comprehensive peace education programme catering for younger and older members of society. It offers the space and opportunity for a community of learning within the museum and welcomes fresh ideas and initiatives from visitors and volunteers. The Tehran Peace Museum is unique in its body of volunteers, men and women who have been directly affected by chemical weapons. They are involved in the Veterans Voices of Peace Oral History Project and actively voice the need for creating peaceful societies in today’s world.     

Portable high‐resolution automated 3D imaging for footwear and tire impression capture

The forensic science community raised the need for improved evidence recognition, collection, and visualization analytical instrumentation for field and laboratory use. While the 3D optical techniques for imaging static objects have been extensively studied, there is still a major gap between current knowledge and collecting high‐quality footwear and tire impression evidence. Among optical means for 3D imaging, digital fringe projection (DFP) techniques reconstruct 3D shape from phase information, achieving camera‐pixel spatial resolution. This paper presents a high‐resolution 3D imaging technology using DFP techniques dedicated to footwear and tire impression capture. We developed fully automated software algorithms and a graphical user interface (GUI) that allow anyone without training to operate for high‐quality 3D data capture. We performed accuracy evaluations and comparisons comparing with the commercial high‐end 3D scanner and carried out qualitative tests for various impressions comparing with the current practices. Overall, our technology achieves similar levels of accuracy and resolution with a high‐end commercially available 3D scanner, while having the merits of being (1) more affordable; (2) much easier to operate; and (3) more robust. Compared with the current practice of casting, our technology demonstrates its superiority because it (1) is non‐destructive; (2) collects more evidence detail than casts, especially when an impression is fragile; (3) requires less time and money to collect each piece of evidence; and (4) results in a digital file that can easily be shared with other examiners.     

荧光钙血迹蓝钠试剂增强潜在多介质混合鞋印的应用

目的研究荧光钙血迹蓝钠试剂增强潜在灰尘水渍混合鞋印、灰尘尿渍混合鞋印、灰尘血渍混合鞋印的普适性。方法采用高压微雾雾化法,雾化增强常见的8种地板上的20%w/w灰尘含量的灰尘水渍、灰尘尿渍和灰尘血渍混合鞋印,并与平面扫描提取技术相比较。结果增强后的鞋印花纹清晰,呈亮蓝色,提取效果明显优于自然光下拍照提取,略优于平面扫描提取技术。结论荧光钙血迹蓝钠试剂能够有效增强潜在多介质混合鞋印,是一种便捷高效的潜在混合鞋印增强提取方法。     

易制毒化学品犯罪及其惩治对策

目前 ,我国易制毒化学品种类较多 ,管理难度大 ,管理漏洞多 ,易制毒化学品犯罪日趋严重。易制毒化学品犯罪的主要特点是涉及数量大 ,品种多 ,主体复杂 ,隐蔽性强。严厉惩治易制毒化学品犯罪 ,必须提高认识 ,加强领导 ,堵住漏洞 ,严格对缉毒人员的培训 ,提高查缉能力 ,同时要完善相关的法律、法规。     

高效红外线辐射燃气灶具节能原理的探讨

新型红外线金属网式燃气灶具可使燃气趋于完全燃烧,提高热效率,达到保护环境的目的。文中重点介绍了灶具的结构,并分析其节能原理。     

无碳复写字迹的化学消退特征初探

无碳复写消退变造文书案件近年呈增多趋势。采用多种常见有机溶剂对无碳复写字迹进行化学消退实验，并比较消退效果及消退特征，可以为化学消退无碳复写字迹的检验提供基础性研究数据。     

光谱成像检验法在朱墨时序鉴定中的应用

光敏印文色料与签字笔书写色料交叉重叠后,因互溶渗透不易形成层状结构而使判定朱墨时序的难度较大。光谱成像检验法是通过比较交叉点、纯印文色料、纯墨迹色料处的反射曲线位置来判定交叉时序关系。     

Automated detection and classification of counterfeit banknotes using quantitative features captured by spectral-domain optical coherence tomography

Counterfeiting of banknotes is still a severe crime problem in many countries. One of the most significant issue for solving the crime is to classify the counterfeit types and identify the sources. Most of the current methods to classify counterfeit banknotes rely on manual examination that is time-consuming and labor-intensive. Moreover, these methods only detect surface features which can be easily imitated through advanced printing technology. In this study, an automated method based on optical coherence tomography (OCT) and machine-learning algorithms was proposed to classify different types of banknotes based on the internal features. A spectral-domain OCT (SD-OCT) system was employed for sub-surface imaging and quantitative assessment of banknotes. A total of 29 Chinese 100-Yuan banknotes were collected, in which 4 of them were real and 25 of them were counterfeiting by three different printing processes. Each banknote was imaged 10 times in 3 distinct regions, which resulted in a dataset of 290 samples. Each sample was characterized by extracting 2 A-scan (OCT signal intensity along depth) based features and 14B-scan (cross-sectional OCT images) based features. Several machine-learning models, including logistic regression (LR), support vector machines (SVM), K-nearest neighbor (KNN) and random forest (RF), were built and optimized as the classifiers that were trained using 203 samples and applied to predict 87 testing samples. The best performance was achieved by SVM classifier in which the sensitivity of 96.55% and specificity of 98.85% were obtained in discriminating between authentic and counterfeit banknotes, and the sensitivity of 94.67% and specificity of 98.22% were obtained in predicting the types of counterfeit banknotes. These classifiers were also evaluated using the receiver operating characteristic (ROC) curves. To the best of our knowledge, this is the first study where A-scan and B-scan derived features from OCT images have been used for the detection and classification of different types of counterfeit banknotes.