Can training improve eyewitness identification? The effect of internal feature focus on memory for faces

Evidence suggests that individuals rely on external features such as hair and face shape when processing and recognising unfamiliar faces. This is problematic in a forensic setting because hairstyle can be changed easily. In two studies we examined whether training individuals to focus more on the stable, internal features of the face (e.g. eyes, nose and mouth) and hence less on the changeable external features would improve identification accuracy. In Study 1, participants were instructed to focus on: (1) internal features, (2) external features, or (3) both internal and external features. Participants’ eye movements were monitored while they studied target faces, which they later tried to identify from an array that included the target with a changed appearance. In Study 2, participants were instructed to focus on: (1) internal features, (2) external features, or (3) given no instructions. Participants were required to identify target faces from line-ups, where they were presented either unchanged or with an altered hairstyle. Results suggested that training individuals to attend to internal features of unfamiliar faces may improve identification accuracy in the common situation where external features have changed between presentation and identification. However, internal feature focus may decrease identification accuracy when external features are unchanged.     

A local variance based approach to alleviate the scene content interference for source camera identification

Identifying the source camera of images is becoming increasingly important nowadays. A popular approach is to use a type of pattern noise called photo-response non-uniformity (PRNU). The noise of image contains the patterns which can be used as a fingerprint. Despite that, the PRNU-based approach is sensitive towards scene content and image intensity. The identification is poor in areas having low or saturated intensity, or in areas with complicated texture. The reliability of different regions is difficult to model in that it depends on the interaction of scene content and the characteristics of the denoising filter used to extract the noise. In this paper, we showed that the local variance of the noise residual can measure the reliability of the pixel for PRNU-based source camera identification. Hence, we proposed to use local variance to characterize the severeness of the scene content artifacts. The local variance is then incorporated to the general matched filter and peak to correlation energy (PCE) detector to provide an optimal framework for signal detection. The proposed method is tested against several state-of-art methods. The experimental results show that the local variance based approach outperformed other state-of-the-art methods in terms of identification accuracy.     

商事登记制度的立法完善

在我国市场经济发展的现阶段,法典意义上的"民商分立"既无可能,亦无必要。由于我国缺乏商法的传统,在商法明显的国际化与统一化的趋向下,制定《商事通则》亦是困难重重。在我国商事立法进程中,当务之急是制定一部统一的《商事登记法》。商事登记法作为商事立法的重要组成部分,体现着商法营利性的核心理念,应当以效率与安全作为立法的基本价值取向。同时在立法中应注意一些具体问题,如商事主体的确认,注册登记与营业登记的分离以及商事登记机关责任的强化等。     

农民工认同社会主义核心价值观的思考

农民工作为中国工人阶级的重要组成部分,其对社会主义核心价值观的认同非常重要.认同的内容包括农民工对中国特色社会主义社会政治的认同、改变和提升农民工的物质生活条件、社会保障内容和丰富农民工的精神文化生活等内容.农民工认同社会主义核心价值观的过程是“外化”过程和“内化”过程的统一.     

马流感病毒NP单克隆抗体的制备及特性鉴定

利用原核表达的马流感病毒(EIV)核蛋白(NP)为免疫原,经腹腔接种4周龄BALB/c小鼠,取其脾细胞与SP2/0骨髓瘤细胞进行融合,经4次有限稀释法克隆和间接ELISA法筛选,获得了3株稳定分泌单抗的杂交瘤细胞株2G11、3E10和4A1,并对它们进行了亚类鉴定、间接ELISA检测和特性鉴定。结果显示,单抗2G11为IgG1亚型,3E10为IgG2a亚型,4A1为IgM亚型,轻链均为κ链。单抗2G11、3E10和4A1的细胞上清液及腹水效价分别为1∶640、1∶640、1∶320和1∶409 600、1∶204 800、0。这3株单抗均能特异性识别EIV NP重组蛋白,并且能够与天然EIV结合;获得的3株单抗与马动脉炎病毒、马疱疹病毒1型、马疱疹病毒4型、马乙型脑炎病毒均不发生交叉反应。亲和力试验结果显示,单抗2G11和3E10与EIV的亲和力常数分别为4.39×106 M-1和2.20×106 M-1。     

大熊猫源停乳链球菌类马亚种的分离与鉴定

为研究引起大熊猫脚掌化脓感染的原因,有效防治该病,对大熊猫感染部位的浓汁进行了细菌学检查及分离,对分离菌进行形态特征、理化特性鉴定、兰氏分群以及16S rDNA序列的分子鉴定,并构建系统发育树;对分离菌进行健康小鼠的人工感染试验。结果分离到5株细菌,根据5株分离菌的形态特征、理化特性及兰氏分群结果,结合16S rDNA序列测定与系统发育分析结果,判定为链球菌属的停乳链球菌类马亚种。该分离菌对供试健康小鼠有较强的致病作用。证实分离菌即为引起大熊猫脚掌化脓感染的病原菌。     

猪伪狂犬病病毒GZ-Z1株的分离鉴定

为获得1株猪伪狂犬病病毒贵州分离株,将贵阳市某猪场送检的流产胎儿病料经一系列处理后接种Vero细胞,并对分离毒株分别进行了病毒理化特性、电镜形态观察、中和试验、动物接种试验、核酸检测等鉴定。当盲传至第3代时,出现细胞变圆变亮、脱落、呈拉网状特征的细胞病变;分离毒不耐酸和热,对5-碘脱氧尿核苷和有机溶剂氯仿敏感,能被伪狂犬病病毒标准阳性血清中和;透射电镜下可见位于囊泡中呈近圆形、有囊膜、150～180 nm大小的成熟病毒粒子,在胞核中可见衣壳呈晶格状排列的病毒包涵体以及空心、实心2种无囊膜的病毒粒子;将分离毒株接种家兔,能引起家兔奇痒、麻痹死亡;PCR扩增产物经测序证明系PRV gD基因的部分序列。结果表明,成功分离获得了1株猪伪狂犬病病毒贵州株。     

DNA条形码技术在兽医寄生虫学研究中的应用

阐述了DNA条形码的概念、DNA条形码基因的筛选方法、DNA条形码的优势与劣势和分析方法,概述了近几年DNA条形码在兽医寄生虫方面的应用情况,旨在引起广大读者对该技术的关注。     

Identification of forensically important sarcophagid flies (Diptera: Sarcophagidae) in China, based on COI and 16S rDNA gene sequences

Insects attracted to cadavers may provide important indications of the postmortem interval (PMI). However, use of the flesh flies (Diptera: Sarcophagidae) for PMI estimation is limited as the species are often not morphologically distinct, especially as immatures. In this study, 23 forensically important flesh flies were collected from 13 locations in 10 Chinese provinces. Then, a 278-bp segment of the cytochrome oxidase subunits one (COI) gene and a 289-bp segment of the 16S rDNA gene of all specimens were successfully sequenced. Phylogenetic analysis of the sequenced segments showed that all sarcophagid specimens were properly assigned into four species (Boerttcherisca peregrina [Robineau-Desvoidy, 1830], Helicophagella melanura [Meigen, 1826], Parasarcophaga albiceps [Meigen, 1826], and Parasarcophaga dux [Thompson, 1869]) with relatively strong supporting values, thus indicating that the COI and 16S rDNA regions are suitable for identification of sarcophagid species. The difference between intraspecific threshold and interspecific divergence confirmed the potential of the two regions for sarcophagid species identification.