Dynamic Suppression of Average Facial Structure Shapes Neural Tuning in Three Macaque Face Patches

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Neuroticism Delays Detection of Facial Expressions

The rapid detection of emotional signals from facial expressions is fundamental for human social interaction. The personality factor of neuroticism modulates the processing of various types of emotional facial expressions; however, its effect on the detection of emotional facial expressions remains unclear. In this study, participants with high- and low-neuroticism scores performed a visual search task to detect normal expressions of anger and happiness, and their anti-expressions within a crowd of neutral expressions. Anti-expressions contained an amount of visual changes equivalent to those found in normal expressions compared to neutral expressions, but they were usually recognized as neutral expressions. Subjective emotional ratings in response to each facial expression stimulus were also obtained. Participants with high-neuroticism showed an overall delay in the detection of target facial expressions compared to participants with low-neuroticism. Additionally, the high-neuroticism group showed higher levels of arousal to facial expressions compared to the low-neuroticism group. These data suggest that neuroticism modulates the detection of emotional facial expressions in healthy participants; high levels of neuroticism delay overall detection of facial expressions and enhance emotional arousal in response to facial expressions.     

研究: 异族面孔分类中情绪的调节作用

人们对异族面孔的分类绩效比本族面孔更好,这称作异族分类优势.但面孔异族分类优势是否也和面孔异族效应一样受到情绪的调节作用,尚未可知.本文通过两个实验考察情绪对于面孔种族分类任务的影响.实验一要求40名大学生被试对不同表情面孔(中性,负性,正性)完成种族判断任务,结果发现,正性和负性情绪使年轻人对异族面孔分类变得更慢,削弱了面孔异族分类优势,而且正性情绪对异族分类效应影响更大.实验二以不同情绪加工特点的老年人为被试,发现老年人对负性异族面孔的分类绩效明显更差,负性情绪对异族分类优势的影响更大.这些结果为异族分类优势理论中,异族面孔分类和个体身份加工过程相互制约的潜在假设提供了进一步的支持.     

Effect of Homocysteine Thiolactone on Structure and Aggregation Propensity of Bovine Pancreatic Insulin

Homocysteine thiolactone (HCTL) is a cyclic thioester of homocysteine, showing high reactivity toward lysine residues of proteins. In the present study the structural properties and aggregation propensity of bovine pancreatic insulin were studied in the presences of increasing concentration of HCTL (0–500 μM), using different spectroscopic techniques. As shown in this study, HCTL induces gross structural alterations and subsequently aggregation of insulin in a dose dependent manner. Also induction of insulin aggregation by HCTL occurs in a sequential process, where native protein with alpha-helical abundant structure gradually transforms into partially folded conformations with the significant amount of beta-sheet. Since C-terminal B-chain of insulin plays a critical role in stability of this protein, the structural alteration/aggregation induced by HCTL can be consequence of homocysteinylation of the only Lysine residue (Lys29) on its B-chain. This study may have important implications regarding the effect of HCTL on structure of insulin particularly in the pathological states linked to hyperhomocysteinemia.     

Structure Based Prediction of Asparagine Deamidation Propensity in Monoclonal Antibodies

Identification of asparagine (Asn) sites that are prone to deamidation is critical for the development of therapeutic monoclonal antibodies (mAbs). Despite a common chemical degradation pathway, the rates of Asn deamidation can vary dramatically among different sites, and prediction of the sensitive deamidation sites is still challenging. In this study, characterization of Asn deamidation for five IgG1 and five IgG4 mAbs under both normal and stressed conditions revealed dramatic differences in the Asn deamidation rates. A comprehensive analysis of the deamidation sites indicated that the deamidation rate differences could be explained by differences in the local structure conformation, structure flexibility and solvent accessibility. A decision tree was developed to predict the deamidation propensity for all Asn sites in IgG mAbs based on the analysis of these three structural parameters. This decision tree will allow potential Asn deamidation hot spots to be identified early in development.     

Lack of Support for the Association between Facial Shape and Aggression: A Reappraisal Based on a Worldwide Population Genetics Perspective

Antisocial and criminal behaviors are multifactorial traits whose interpretation relies on multiple disciplines. Since these interpretations may have social, moral and legal implications, a constant review of the evidence is necessary before any scientific claim is considered as truth. A recent study proposed that men with wider faces relative to facial height (fWHR) are more likely to develop unethical behaviour mediated by a psychological sense of power. This research was based on reports suggesting that sexual dimorphism and selection would be responsible for a correlation between fWHR and aggression. Here we show that 4,960 individuals from 94 modern human populations belonging to a vast array of genetic and cultural contexts do not display significant amounts of fWHR sexual dimorphism. Further analyses using populations with associated ethnographical records as well as samples of male prisoners of the Mexico City Federal Penitentiary condemned by crimes of variable level of inter-personal aggression (homicide, robbery, and minor faults) did not show significant evidence, suggesting that populations/individuals with higher levels of bellicosity, aggressive behaviour, or power-mediated behaviour display greater fWHR. Finally, a regression analysis of fWHR on individual''s fitness showed no significant correlation between this facial trait and reproductive success. Overall, our results suggest that facial attributes are poor predictors of aggressive behaviour, or at least, that sexual selection was weak enough to leave a signal on patterns of between- and within-sex and population facial variation.     

Serotonin Transporter Gene-Linked Polymorphism Affects Detection of Facial Expressions

Previous studies have demonstrated that the serotonin transporter gene-linked polymorphic region (5-HTTLPR) affects the recognition of facial expressions and attention to them. However, the relationship between 5-HTTLPR and the perceptual detection of others'' facial expressions, the process which takes place prior to emotional labeling (i.e., recognition), is not clear. To examine whether the perceptual detection of emotional facial expressions is influenced by the allelic variation (short/long) of 5-HTTLPR, happy and sad facial expressions were presented at weak and mid intensities (25% and 50%). Ninety-eight participants, genotyped for 5-HTTLPR, judged whether emotion in images of faces was present. Participants with short alleles showed higher sensitivity (d′) to happy than to sad expressions, while participants with long allele(s) showed no such positivity advantage. This effect of 5-HTTLPR was found at different facial expression intensities among males and females. The results suggest that at the perceptual stage, a short allele enhances the processing of positive facial expressions rather than that of negative facial expressions.     

Sequential Effects in Judgements of Attractiveness: The Influences of Face Race and Sex

In perceptual decision-making, a person’s response on a given trial is influenced by their response on the immediately preceding trial. This sequential effect was initially demonstrated in psychophysical tasks, but has now been found in more complex, real-world judgements. The similarity of the current and previous stimuli determines the nature of the effect, with more similar items producing assimilation in judgements, while less similarity can cause a contrast effect. Previous research found assimilation in ratings of facial attractiveness, and here, we investigated whether this effect is influenced by the social categories of the faces presented. Over three experiments, participants rated the attractiveness of own- (White) and other-race (Chinese) faces of both sexes that appeared successively. Through blocking trials by race (Experiment 1), sex (Experiment 2), or both dimensions (Experiment 3), we could examine how sequential judgements were altered by the salience of different social categories in face sequences. For sequences that varied in sex alone, own-race faces showed significantly less opposite-sex assimilation (male and female faces perceived as dissimilar), while other-race faces showed equal assimilation for opposite- and same-sex sequences (male and female faces were not differentiated). For sequences that varied in race alone, categorisation by race resulted in no opposite-race assimilation for either sex of face (White and Chinese faces perceived as dissimilar). For sequences that varied in both race and sex, same-category assimilation was significantly greater than opposite-category. Our results suggest that the race of a face represents a superordinate category relative to sex. These findings demonstrate the importance of social categories when considering sequential judgements of faces, and also highlight a novel approach for investigating how multiple social dimensions interact during decision-making.     

Face Mask Sampling for the Detection of Mycobacterium tuberculosis in Expelled Aerosols

Background

Although tuberculosis is transmitted by the airborne route, direct information on the natural output of bacilli into air by source cases is very limited. We sought to address this through sampling of expelled aerosols in face masks that were subsequently analyzed for mycobacterial contamination.

Methods

In series 1, 17 smear microscopy positive patients wore standard surgical face masks once or twice for periods between 10 minutes and 5 hours; mycobacterial contamination was detected using a bacteriophage assay. In series 2, 19 patients with suspected tuberculosis were studied in Leicester UK and 10 patients with at least one positive smear were studied in The Gambia. These subjects wore one FFP30 mask modified to contain a gelatin filter for one hour; this was subsequently analyzed by the Xpert MTB/RIF system.

Results

In series 1, the bacteriophage assay detected live mycobacteria in 11/17 patients with wearing times between 10 and 120 minutes. Variation was seen in mask positivity and the level of contamination detected in multiple samples from the same patient. Two patients had non-tuberculous mycobacterial infections. In series 2, 13/20 patients with pulmonary tuberculosis produced positive masks and 0/9 patients with extrapulmonary or non-tuberculous diagnoses were mask positive. Overall, 65% of patients with confirmed pulmonary mycobacterial infection gave positive masks and this included 3/6 patients who received diagnostic bronchoalveolar lavages.

Conclusion

Mask sampling provides a simple means of assessing mycobacterial output in non-sputum expectorant. The approach shows potential for application to the study of airborne transmission and to diagnosis.     

Sex Differences in the Rapid Detection of Emotional Facial Expressions

Background

Previous studies have shown that females and males differ in the processing of emotional facial expressions including the recognition of emotion, and that emotional facial expressions are detected more rapidly than are neutral expressions. However, whether the sexes differ in the rapid detection of emotional facial expressions remains unclear.

Methodology/Principal Findings

We measured reaction times (RTs) during a visual search task in which 44 females and 46 males detected normal facial expressions of anger and happiness or their anti-expressions within crowds of neutral expressions. Anti-expressions expressed neutral emotions with visual changes quantitatively comparable to normal expressions. We also obtained subjective emotional ratings in response to the facial expression stimuli. RT results showed that both females and males detected normal expressions more rapidly than anti-expressions and normal-angry expressions more rapidly than normal-happy expressions. However, females and males showed different patterns in their subjective ratings in response to the facial expressions. Furthermore, sex differences were found in the relationships between subjective ratings and RTs. High arousal was more strongly associated with rapid detection of facial expressions in females, whereas negatively valenced feelings were more clearly associated with the rapid detection of facial expressions in males.

Conclusion

Our data suggest that females and males differ in their subjective emotional reactions to facial expressions and in the emotional processes that modulate the detection of facial expressions.     

基于发育网络识别模型的大熊猫面部识别

个体识别是动物行为学与生态学研究工作的基础,也是制定珍稀野生动物保护政策的重要依据。为了丰富大熊猫个体识别和种群数量调查的方法,我们于2017年7月分别在四川省雅安市碧峰峡大熊猫基地和四川省汶川县耿达镇的中华大熊猫苑共计拍摄18只大熊猫个体,每只大熊猫拍摄6~13张高质量面部照片（共计131张）,利用发育网络（Developmental Network）建立大熊猫面部识别模型。利用此模型对存在部分背景的大熊猫面部照片进行识别检测,得到的个体识别率为79.41%,对完全去除背景的大熊猫面部照片进行识别检测,得到的个体识别率为58.82%。研究表明,发育网络具有足够的大熊猫个体识别能力,不同背景比例的照片对大熊猫个体识别的实际结果具有较大的影响。随着发育网络识别模型的发展,我们建议更多的野生动物保护研究者结合这一技术深入地开展珍稀野生动物（如大熊猫）个体识别研究,逐步提高识别准确度,并应用到关键区域大规模的动物调查中。     

从体质特征看中国南方汉族的人种归属

2009年至2012年研究组调查了中国南方汉族15154例(男性为7340例,女性为7814例)的身高、体重和16项测量指标,并计算出12项指数,将南方汉族与蒙古人种北亚类型族群、南亚类型族群及东亚类型族群的韩国人、日本人进行了比较。结果显示:1)南方汉族头面部主要指标介于北亚、南亚类型族群之间;南方汉族男性更接近于北亚类型族群,而南方汉族女性比男性头面部特征更接近南亚类型族群。2)南方汉族男性头部的长、宽、高、围度小于东亚类型族群,面部比韩国人、日本人狭窄;南方汉族女性头的长、宽、围度、下颌角间宽值小于韩国人、日本人,头较高,面部比韩国人、日本人狭窄。南方汉族男性、女性与韩国人、日本人体质差异较大。3)聚类分析结果提示,中国南方汉族与韩国人、日本人体质差异较大。南方汉族男性体质相对接近于北亚类型族群,女性体质介于北亚、南亚类型族群之间。华南汉族体质在南方汉族中有一定的特殊性。     

Prediction of Peptide and Protein Propensity for Amyloid Formation

Understanding which peptides and proteins have the potential to undergo amyloid formation and what driving forces are responsible for amyloid-like fiber formation and stabilization remains limited. This is mainly because proteins that can undergo structural changes, which lead to amyloid formation, are quite diverse and share no obvious sequence or structural homology, despite the structural similarity found in the fibrils. To address these issues, a novel approach based on recursive feature selection and feed-forward neural networks was undertaken to identify key features highly correlated with the self-assembly problem. This approach allowed the identification of seven physicochemical and biochemical properties of the amino acids highly associated with the self-assembly of peptides and proteins into amyloid-like fibrils (normalized frequency of β-sheet, normalized frequency of β-sheet from LG, weights for β-sheet at the window position of 1, isoelectric point, atom-based hydrophobic moment, helix termination parameter at position j+1 and ΔG° values for peptides extrapolated in 0 M urea). Moreover, these features enabled the development of a new predictor (available at http://cran.r-project.org/web/packages/appnn/index.html) capable of accurately and reliably predicting the amyloidogenic propensity from the polypeptide sequence alone with a prediction accuracy of 84.9 % against an external validation dataset of sequences with experimental in vitro, evidence of amyloid formation.     

Pain and Empathy: The Effect of Self-Oriented Feelings on the Detection of Painful Facial Expressions

Background

Painful facial expressions have been shown to trigger affective responses among observers. However, there is so far no clear indication about the self- or other-oriented nature of these feelings. The purpose of this study was to assess whether facial expressions of pain are unconsciously associated with other-oriented feelings (empathic concern) or with self-oriented feelings (personal distress).

Method

70 participants took part in a priming paradigm in which ambiguous facial expressions of pain were primed by words related to empathic concern, distress, negative or by neutral words. It was hypothesized that empathic concern or distress-related words might facilitate the detection of pain in ambiguous facial expressions of pain, independently of a mere effect of prime (i.e., neutral words) or an effect of valence congruency (negative primes).

Results

The results showed an effect of prime on the detection and on the reaction time to answer “pain” when confronted to ambiguous facial expressions of pain. More specifically, the detection of pain was higher and faster when preceded by distress primes relative to either neutral or negative primes.

Conclusion

The present study suggests that painful expressions are unconsciously related to self-oriented feelings of distress and that their threat value might account for this effect. These findings thus shed new light on the automatic relationship between painful expressions and the affective components of empathy.     

Introducing a Rigid Loop Structure from Deer into Mouse Prion Protein Increases Its Propensity for Misfolding In Vitro

Prion diseases are fatal neurodegenerative disorders characterized by misfolding of the cellular prion protein (PrP^c) into the disease-associated isoform (PrP^Sc) that has increased β-sheet content and partial resistance to proteolytic digestion. Prion diseases from different mammalian species have varying propensities for transmission upon exposure of an uninfected host to the infectious agent. Chronic Wasting Disease (CWD) is a highly transmissible prion disease that affects free ranging and farmed populations of cervids including deer, elk and moose, as well as other mammals in experimental settings. The molecular mechanisms allowing CWD to maintain comparatively high transmission rates have not been determined. Previous work has identified a unique structural feature in cervid PrP, a rigid loop between β-sheet 2 and α-helix 2 on the surface of the protein. This study was designed to test the hypothesis that the rigid loop has a direct influence on the misfolding process. The rigid loop was introduced into murine PrP as the result of two amino acid substitutions: S170N and N174T. Wild-type and rigid loop murine PrP were expressed in E. coli and purified. Misfolding propensity was compared for the two proteins using biochemical techniques and cell free misfolding and conversion systems. Murine PrP with a rigid loop misfolded in cell free systems with greater propensity than wild type murine PrP. In a lipid-based conversion assay, rigid loop PrP converted to a PK resistant, aggregated isoform at lower concentrations than wild-type PrP. Using both proteins as substrates in real time quaking-induced conversion, rigid loop PrP adopted a misfolded isoform more readily than wild type PrP. Taken together, these findings may help explain the high transmission rates observed for CWD within cervids.     

Structure of Actinomycin based on Conformational Studies

ACTINOMYCIN (Fig. 1) inhibits DNA dependent RNA synthesis and binds specifically to DNA and double stranded poly-deoxyribonucleotides. The three-dimensional structure of actinomycin is therefore relevant to the molecular mechanism of its biological activity and the stereochemistry of replication.     

反硝化功能基因—— 检测反硝化菌种群结构的分子标记

反硝化菌种类繁多, 且分属多个分类学上的不同种属, 故不能利用常规的16S rRNA测序方法对其进行研究。利用编码反硝化酶的功能基因作为分子标记, 可以有效研究环境样品中反硝化菌的种群结构、数量以及活性等。本文重点介绍了主要的反硝化功能基因以及常用的扩增引物, 分析了反硝化功能基因与16S rRNA系统发育之间的关系, 比较了nirS和nirK基因菌的群落分布特征, 对目前反硝化功能基因的研究和应用现状进行了综述, 讨论了研究中发现的新问题, 期望为研究复杂微生物的生态特征提供参考。