Does face image statistics predict a preferred spatial frequency for human face processing?

Psychophysical experiments suggested a relative importance of a narrow band of spatial frequencies for recognition of face identity in humans. There exists, however, no conclusive evidence of why it is that such frequencies are preferred. To address this question, I examined the amplitude spectra of a large number of face images and observed that face spectra generally fall off more steeply with spatial frequency compared with ordinary natural images. When external face features (such as hair) are suppressed, then whitening of the corresponding mean amplitude spectra revealed higher response amplitudes at those spatial frequencies which are deemed important for processing face identity. The results presented here therefore provide support for that face processing characteristics match corresponding stimulus properties.     

Smoker's face: an underrated clinical sign?

In a prospective survey of patients attending a general medical outpatient clinic roughly half the current cigarette smokers who had smoked for 10 years or more were identified, using defined criteria, by their facial features alone. These facial features, designated "smoker''s face," were present in three (8%) of those who had smoked cigarettes for 10 years or more in the past and in none of the non-smokers. The association of smoker''s face with current smoking that had continued for 10 years or more was significant (p less than 0.001) and remained after the patient''s age, social class, exposure to sunlight, recent change of weight, and estimated lifetime consumption of cigarettes were controlled for. Smoker''s face may be a helpful indicator in antismoking campaigns.     

Are developing countries prepared to face Ebola-like outbreaks?

<正>Ebola virus disease has caused havoc in West Africa,with 11,162deaths and more than 27,181 cases(as of May 31,2015)being reported since the virus emerged in early2014 in Guinea.The maximum number of cases has been reported in Sierra Leone(12,827),while most of the reported deaths have occurred in Liberia(4,806),according to the Center for Disease Control and     

How is the individuality of a face recognized?

A familiar face is instantly recognized in a crowd. This cannot be achieved through a feature by feature comparison of the observed face with either an average face (norm-based model of face recognition) or with a set of similarly constructed faces stored in memory (exemplar-based model of face recognition). A modified norm-based model is thus proposed. Instead of memorizing an average face, the normal variations for each facial feature are used to construct a multidimensional volume of face-space devoid of unusual features, here defined as features whose metrics lie below the 5th or above the 95th percentiles for that feature. A face consisting of 100 independently variable features will thus have, on average, 10 unusual features. Face identification then becomes exception-reporting. It requires only 10 such rare features to render a given face a one in 10¹³ faces (P=0.05¹⁰=9.8×10⁻¹⁴). In a world containing 6.7×10⁹ people, such a face would be unique. Faces remembered in this way can have their unusual features exaggerated or attenuated without loss of identity. This is the basis of caricatures and anti-caricatures. It also means that individuals belonging to a foreign race, possessing several features with modes beyond the “usual range” of the own-race population, will all look alike. Features that render a face unique in the own-race population are now shared by everyone in the foreign race.Average faces are more beautiful than the faces used in the averaging process. This makes evolutionary sense. Natural selection increases the frequency of fit features at the expense of maladaptive features. “Usual features” are therefore fitter than “unusual features”, and play an important role in mate selection. Such an existing fundamental sexual attribute could easily have been harnessed for the fast and efficient recognition of individuals in the community.     

The unknown face of IRE1α – Beyond ER stress

IRE1α (Inositol Requiring kinase Enzyme 1 alpha), a transmembrane protein localized to the endoplasmic reticulum (ER) is a master regulator of the unfolded protein response (UPR) pathway. The fate determining steps during ER stress-induced apoptosis are greatly attributed to IRE1α’s endoribonuclease and kinase activities. Apart from its role as a chief executioner in ER stress, recent studies have shown that upon activation in the presence or absence of ER stress, IRE1α executes multiple cellular processes such as differentiation, immune response, progression and repression of the cell cycle. Besides its crucial role in protein misfolding, the versatile contributions of IRE1α in other cellular functions are greatly unknown. In this review, we have discussed the structural conservation of IRE1 among eukaryotes, the mechanisms underlying its activation and the recent understandings of the non-apoptotic functions of IRE1 other than ER stress-induced cell death.     

Genetically modified laboratory animals--what welfare problems do they face?

In this article, we respond to public concern expressed about the welfare of genetically modified (GM) nonhuman animals. As a contribution to the debate on this subject, we attempt in this article to determine in what situations the practice of genetic modification in rodents may generate significant welfare problems. After a brief discussion of the principles of animal welfare, we focus on the problem of animal suffering and review some types of gene modifications likely to cause predictable welfare problems. In this article, we also consider suffering that may be involved in the process of generating GM animals. Finally, we discuss the role of GM animals in attempts to reduce, replace, and refine the use of animals in research.     

Ectodermal Wnt/β-catenin signaling shapes the mouse face

The canonical Wnt/β-catenin pathway is an essential component of multiple developmental processes. To investigate the role of this pathway in the ectoderm during facial morphogenesis, we generated conditional β-catenin mouse mutants using a novel ectoderm-specific Cre recombinase transgenic line. Our results demonstrate that ablating or stabilizing β-catenin in the embryonic ectoderm causes dramatic changes in facial morphology. There are accompanying alterations in the expression of Fgf8 and Shh, key molecules that establish a signaling center critical for facial patterning, the frontonasal ectodermal zone (FEZ). These data indicate that Wnt/β-catenin signaling within the ectoderm is critical for facial development and further suggest that this pathway is an important mechanism for generating the diverse facial shapes of vertebrates during evolution.     

中国灵长类文献纵览

把1870—2001年来自美国“现代灵长类文献题录数据库”、“维普中文数据库”及“中国灵长类研究文献题录”的资料按4个时期（I：1870—1949；II：1950—1965；III：1966—1977；IV：1978—2001）分类整理。此外，使用了“科学引文数据库（扩展版）”。结果如下：（1）1870—2001年共有2 052篇文献，2个文献数量高峰分别出现于1950—1965和1978—2001年；科研部门所发表的论文占54.2%，并随时间而增加；而国外部门则随之减少。（2）2 052篇文献中，超过9%的文献为SCI所收录，其中1966—1977年被SCI收录的文献百分比最高；在全部被SCI收录的文献中又以科研部门的占优势（59.1%）；但国外部门则以其30.1%的文献被SCI收录而领先。（3）统计了灵长类研究9个领域文献百分比及其变化，其中1978—2001间生态学和行为、神经生物学、繁殖和饲养快速发展；化石灵长类、形态学和解剖学减少；分类及分布、细胞及分子进化显得不甚突出；在第II时期和第 IV时期疾病防治研究相当多；保护生物学得到越来越多的关注。第IV时期作者数量最多，但每个作者的文献平均数却不如第I时期。一般地说，在SCI收录的作者中以中国作者居多，但在第I时期唯一被SCI收录的作者则是一名外国学者；在第III时期外国作者占被收录作者数的60%。     

What makes a cell face selective? The importance of contrast

Faces are robustly detected by computer vision algorithms that search for characteristic coarse contrast features. Here, we investigated whether face-selective cells in the primate brain exploit contrast features as well. We recorded from face-selective neurons in macaque inferotemporal cortex, while presenting?a face-like collage of regions whose luminances were changed randomly. Modulating contrast combinations between regions induced activity changes ranging from no response to a response greater than that to a real face in 50% of cells. The critical stimulus factor determining response magnitude was contrast polarity, for example, nose region brighter than left eye. Contrast polarity preferences were consistent across cells, suggesting a common computational strategy across the population, and matched features used by computer vision algorithms for face detection. Furthermore, most cells were tuned both for contrast polarity and for the geometry of facial features, suggesting cells encode information useful both for detection and recognition.     

The real face of HIF1α in the tumor process

It is well known that the hypoxia-inducible factor 1 α (HIF1α) is detectable as adaptive metabolic response to hypoxia. However, HIF1/HIF1α is detectable even under normoxic conditions, if the metabolism is altered, e.g., high proliferation index. Importantly, both hypoxic metabolism and the Warburg effect have in common a decrease of the intracellular pH value.

In our interpretation, HIF1α is not directly accumulated by hypoxia, but by a process which occurs always under hypoxic conditions, a decrease of the intracellular pH value because of metabolic imbalances. We assume that HIF1α is a sensitive controller of the intracellular pH value independently of the oxygen concentration. Moreover, HIF1α has its major role in activating genes to eliminate toxic metabolic waste products (e.g., NH₃/NH₄+) generated by the tumor-specific metabolism called glutaminolysis, which occur during hypoxia, or the Warburg effect. For that reason, HIF1α appears as a potential target for tumor therapy to disturb the pH balance and to inhibit the elimination of toxic metabolic waste products in the tumor cells.     

贺兰山马鹿冬季食性分析

2003年11月—2004年2月在宁夏贺兰山国家级自然保护区和内蒙古贺兰山国家级自然保护区，利用粪便显微组织学分析技术结合野外啃食调查对马鹿阿拉善亚种（Cervus elaphus alxaicus）冬季食性进行了研究。从7个沟系中一共收集了219堆马鹿粪便中捡拾粪粒，组成14个复合样本进行分析，其结果表明，灰榆（27.37%）、山杨（11.75%）、蒙古扁桃（9.83%）、金露梅（8.12%）、锦鸡儿（6.52%）等植物的当年枝和落叶以及禾本科草本植物（7.51%）是马鹿冬季主要食物，其中灰榆为大宗食物，针叶树种（杜松、油松、青海云杉）和其他草本植物所占比例均较小。马鹿对灰榆、山杨、蒙古扁桃、金露梅、锦鸡儿和杜松有正选择性；而对禾本科草本植物、油松和青海云杉有负选择性。马鹿对它们选择性的强弱顺序为：山杨＞杜松＞锦鸡儿＞蒙古扁桃＞金露梅＞灰榆＞禾本科草本植物＞油松＞青海云杉。马鹿取食乔木36.8%、灌木44.7%、禾本科草本植物8.0%和非禾本科草本植物10.5%，这4类植物的利用性与可利用性存在极显著差异，乔木和灌木的利用性高于可利用性；禾本科草本植物和非禾本科草本植物的利用性低于可利用性，说明马鹿的食物以木本植物为主，草本植物为辅。Spearman相关分析得出马鹿对食物的选择性与水分、灰分、粗蛋白、粗脂肪、粗纤维和无氮浸出物之间无明显的相关关系。被啃食植物中粗蛋白含量较高，蛋白质不是越冬马鹿的限制因子，而能量可能是影响冬季马鹿采食较为关键的因子。马鹿冬季采食策略主要是以最小的能量消耗获取最大的能量收益。     

鱼类特异的基因组复制

辐鳍鱼类是脊椎动物中种类最多、分布最广的类群，其基因组大小不等。过去的观点认为，在脊椎动物进化历程中曾发生了两次基因组复制。近期的系统基因组学研究资料进一步提出，在大约350百万年，辐鳍鱼还发生了第三次基因组复制，即鱼类特异的基因组复制(fishspecific genome duplication，FSGD)，且发生的时间正处在“物种极度丰富”的硬骨鱼谱系(真骨总目)和“物种贫乏”的谱系(辐鳍鱼纲基部的类群)出现分歧的时间点，表明FSGD与硬骨鱼物种和生物多样性的增加有关。进一步开展鱼类比较基因组学和功能基因组学研究将进一步验证FSGD这一假说。     

广州地区犬蝠的食性

2004年5月—2006年4月采用拾遗法、粪便内容物分析法及实地观察对广州地区常见的食果蝙蝠¬—犬蝠(Cynopterus sphinx)进行了食性研究。对26份食物残留物和粪便样品的分析结果表明：犬蝠的食物包含13科21种的植物果实,3科3种的植物叶片,如：蒲桃（Syzygium jambos）、蒲葵（Livistona subglobosa）及龙眼（Dimocarous longan）的果实。其食性随果实的成熟季节而出现明显的季节性变化,夏秋两季大量食用各种水果,而在食物欠缺的春冬两季则主要食用棕榈科蒲葵的种子。广州地区犬蝠的繁殖期在每年的5—10月。     

Roma women in Athenian firms: do they face wage bias?

In the current study, we analyse the effect of having a Roma background on women's wages. By utilizing data from sixteen multiethnic municipalities in which Roma live, we estimate that 66.2 per cent of the wage differential between Roma and non-Roma female workers cannot be explained by differences in observed characteristics. Prejudices against Roma women are discussed and appear to explain the wage gap found here. The occupational segregation of the Roma in low-paid jobs and employers' statistical motivations are also found to influence wages earned by Roma. This study concludes that there is a need for better implementation of existing laws, rules and regulations, which would counter the discrimination against minority women in the labour market. In addition, a better means of assessing workers' skills might contribute to the reduction of wage discrimination, and greater educational achievement would significantly boost the economic status of Roma women.