Origins and antiquity of X-linked triallelic color vision systems in New World monkeys

It is known that the squirrel monkey, marmoset, and other related New World (NW) monkeys possess three high-frequency alleles at the single X-linked photopigment locus, and that the spectral sensitivity peaks of these alleles are within those delimited by the human red and green pigment genes. The three alleles in the squirrel monkey and marmoset have been sequenced previously. In this study, the three alleles were found and sequenced in the saki monkey, capuchin, and tamarin. Although the capuchin and tamarin belong to the same family as the squirrel monkey and marmoset, the saki monkey belongs to a different family and is one of the species that is most divergent from the squirrel monkey and marmoset, suggesting the presence of the triallelic system in many NW monkeys. The nucleotide sequences of these alleles from the five species studied indicate that gene conversion occurs frequently and has partially or completely homogenized intronic and exonic regions of the alleles in each species, making it appear that a triallelic system arose independently in each of the five species studied. Nevertheless, a detailed analysis suggests that the triallelic system arose only once in the NW monkey lineage, from a middle wavelength (green) opsin gene, and that the amino acid differences at functionally critical sites among alleles have been maintained by natural selection in NW monkeys for >20 million years. Moreover, the two X-linked opsin genes of howler monkeys (a NW monkey genus) were evidently derived from the incorporation of a middle (green) and a long wavelength (red) allele into one chromosome; these two genes together with the (autosomal) blue opsin gene would immediately enable even a male monkey to have trichromatic vision.     

网页设计中色彩视觉元素探究

以网页界面中的色彩视觉元素为研究对象,总结网页界面中的色彩元素特性,结合色彩属性与实际网页色彩设计表象,探讨基于网页界面的配色方法,并通过分析影响网页界面色彩视觉效果的各种因素,指出网页色彩设计中存在的问题与实际设计中的经验,力求为国内网页设计的美化与创新提供一定的理论依据与实例参考.     

Mechanisms of central color vision

PURPOSE: To evaluate the effectiveness of limbal relaxing incisions (LRIs) for correcting corneal astigmatism during cataract surgery. SETTING: Cullen Eye Institute, Houston, Texas, USA. METHODS: In 12 eyes of 11 patients, cataract surgery was combined with LRIs. The LRIs were made according to a modified Gills nomogram and were based on preoperative corneal astigmatism determined with standard keratometry and computerized videokeratography (EyeSys Corneal Analysis System Version 3.2). RESULTS: The mean preoperative keratometric cylinder was 2.46 +/- 0.81 diopters (D). At 1 month postoperatively, mean arithmetic reduction in keratometric cylinder was 1.12 +/- 0.74 D, and the with-the-wound (WTW) change (calculated by Holladay, Cravy, Koch vector analysis formula) was -0.70 +/- 0.44. From 1 day to 1 month postoperatively, there was 0.55 D of WTW regression with minimal change in the mean cylindrical axis. There were no overcorrections. CONCLUSION: Limbal relaxing incisions are a practical, simple, and forgiving approach to the correction of astigmatism during cataract surgery.     

Individual variations in color vision among squirrel monkeys (Saimiri sciureus) of different geographical origins.

Used a forced-choice discrimination procedure to test color vision and visual sensitivity in 10 adult feral squirrel monkeys originating from 3 locations—Bolivia, Columbia, Guyana. Ss included 4 females and 6 males. In agreement with results from an earlier study by the present 1st author (in press) of vision in squirrel monkeys of Peruvian origin, striking individual variations in color vision were found among these Ss. Some Ss had trichromatic color vision, while others were dichromats. Within these 2 categories, a total of 5 color vision phenotypes could be discerned. Most of these types were qualitatively similar to common forms of human color-defective vision. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Selection by color and form in vision.

Whether attention to a local part of a visual display can prevent access to semantic information in form matching tasks with objects was studied. A first picture containing a line segment (the reference) was followed by 2 lateral objects also containing a line segment (a target and a distractor). Participants matched the line segments according to either their orientation or color. Effects of semantic information were assessed by manipulating the semantic relations among the pictures surrounding the reference, target, and distractor. Semantic information affected performance in the orientation matching task, but not in the color matching task. Results suggest the existence of separate selection mechanisms in vision. Selection of local colors for response purposes can be based on inhibition of the form pathway (eliminating semantic effects on matching). Selection within the form pathway can involve a bias toward global shape (the picture). Once attention is allocated to global shape, associated semantic representations are activated and semantic effects on matching emerge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Spatial and temporal aspects of infant color vision

The present paper constitutes a review of the literature on young infants' chromatic discrimination capabilities. A series of early studies showed that infants as young as two months postnatal can make at least some chromatic discriminations between stationary, homogeneous fields of different wavelength compositions. Current studies of spatial and temporal contrast sensitivity functions (CSFs) for red/green isoluminant stimuli suggest that spatial chromatic CSFs show developmental changes in sensitivity and spatial scale, but not curve shape; while temporal chromatic CSFs (tCSFs) show developmental changes in sensitivity and curve shape, but not temporal scale. Infants can also code the direction of motion of moving isoluminant red/green gratings, for both continuous and quadrature motion. The possible mechanisms that underlie infants' chromatic discriminations are discussed.     

Color vision and color naming: A psychophysiological hypothesis of cultural difference.

Proposes an hypothesis which relates physiological differences in visual processing to semantic categorization. A comparison of primary color-naming systems across cultures reveals a regular geographic patterning of color-naming confusions. These semantic data indicative of a short wavelength (blue) insensitive, so-called tritan, color vision have been corroborated by psychophysically measured depressions in spectral sensitivity and confusions in color matching. Yellow intraocular pigmentation which is biometeorologically adaptive and which attenuates effective short wavelength radiation is assessed to contribute in varying degrees toward mimicry of the tritan color-vision complex. Furthermore, the density of yellow intraocular pigmentation is found to parallel the worldwide distribution of collapsed color-naming systems (51/2 p. ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mapping of cortical areas involved in color vision in non-human primates

Foreign body (FB) injury from aspiration or ingestion is a common pediatric health problem. Diagnosis relies on clinical judgment plus medical history, physical examination, and radiographic evaluation. A multi-institutional review of 1269 FB events revealed that 85% were correctly diagnosed following a single physician encounter. However, 15% of the children had an elusive diagnosis (>1 week), despite previous evaluation. Delays in diagnosis were seven times more likely to occur in aspirations than in ingestions. Secondary injuries (e.g., pneumonia and atelectasis) occurred in 13% of airway FBs but in only 1.7% of esophageal FBs. Plain radiographs were used in 82% of children, and special studies (e.g., fluoroscopy) in only 7%. We conclude that diagnosis of FB injury in children is frequently achieved at the initial evaluation but that continued surveillance by follow-up visits to health care facilities from parents and other caretakers is important, to reduce pulmonary injuries.     

Vision in the prairie dog: Spectral sensitivity and color vision.

Assessed visual sensitivity and color vision discrimination tests with 2 male and 3 female black-tailed prairie dogs. As measured in an increment-threshold situation, (Exp I), spectral sensitivity functions peak at 520-540 nm. For different states of adaptation there was little change in the location of peak spectral sensitivity, although at higher light levels the function had a somewhat more complex form. In Exp II, it was found that Ss' threshold was slightly lower than that for other cone visual systems. Tests for the presence of a spectral neutral point and for chromaticity confusions in Exp III revealed that Ss have color vision of the dichromatic variety. Like other gound-dwelling sciurids examined previously, the dichromacy of the prairie dog is closest to that shown by human protanopes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

知识图谱的最新进展、关键技术和挑战

跨模态图像−文本检索是一项在给定一种模态（如文本）的查询条件下检索另一种模态（如图像）的任务. 该任务的关键问题在于如何准确地测量图文两种模态之间的相似性,在减少视觉和语言这两种异构模态之间的视觉语义差异中起着至关重要的作用. 传统的检索范式依靠深度学习提取图像和文本的特征表示,并将其映射到一个公共表示空间中进行匹配. 然而,这种方法更多地依赖数据表面的相关关系,无法挖掘数据背后真实的因果关系,在高层语义信息的表示和可解释性方面面临着挑战. 为此,在深度学习的基础上引入因果推断和嵌入共识知识,提出嵌入共识知识的因果图文检索方法. 具体而言,将因果干预引入视觉特征提取模块,通过因果关系替换相关关系学习常识因果视觉特征,并与原始视觉特征进行连接得到最终的视觉特征表示. 为解决本方法文本特征表示不足的问题,采用更强大的文本特征提取模型BERT（Bidirectional encoder representations from transformers,双向编码器表示）,并且嵌入两种模态数据之间共享的共识知识对图文特征进行共识级的表示学习. 在MS-COCO数据集以及MS-COCO 到Flickr30k上的跨数据集实验,证明了本文方法可以在双向图文检索任务上实现召回率和平均召回率的一致性改进.

     

Photopigment basis for dichromatic color vision in cows, goats, and sheep

Electroretinogram (ERG) flicker photometry was used to measure the spectral properties of cones in three common ungulates-cattle (Bos taurus), goats (Capra hircus), and sheep (Ovis aries). Two cone mechanisms were identified in each species. The location of peak sensitivity of an S-cone mechanism varied from about 444 to 455 nm for the three species; analogous values for an M/L-cone were tightly clumped at about 552-555 nm. Each of these three species has the requisite photopigment basis for dichromatic color vision and they are, thus, similar to other ungulates examined earlier.     

带钢视觉检测系统的研究现状及展望

应用机器视觉技术进行带钢表面检测,能够在线实时检测并识别带钢表面出现的夹杂、划伤、辊印等缺陷,同时能够对缺陷的图像、种类、数量和位置等信息进行有效的统计和保存.本文介绍了基于机器视觉的带钢表面自动检测系统的基本原理和结构,比较分析了两种典型系统的结构、原理和性能,并指出了当前研究工作面临的问题和今后的发展趋势.     

Shift of equiluminance in congenital color vision deficiencies: pattern-ERG, VEP and psychophysical findings

A case of the HELLP syndrome is reported that was initially diagnosed as cholecystitis. Much overlap exists between the two diagnoses, and the emergency physician must be aware of the important differences between them. Because the HELLP syndrome and preeclampsia may occur in both the second and third trimesters, they represent serious diagnoses that must be considered when evaluating a pregnant patient with right upper quadrant abdominal pain.     

A vision for psychopharmacology

Jarisch-Herxheimer reaction (J-HR) is an acute febrile reaction which may complicate the initiation of an effective treatment against infections due to intracellular micro-organisms. We report a case of J-HR complicating treatment of chronic Q fever endocarditis with demonstration of elevated serum cytokine concentrations.     

Polymorphism in the number of genes encoding long-wavelength-sensitive cone pigments among males with normal color vision

Examination by direct DNA sequence analysis of the X-linked visual pigment genes in 27 males with normal color vision reveals that almost half have two or more different genes encoding a long-wavelength-sensitive cone pigment. This is counter to the conventional theory proposed from results of Southern hybridization studies that there is a single long-wave pigment gene per X-chromosome. Further, the sequences and consideration of the structure of the X-linked pigment gene array suggest that the majority of the observers (as many as 2/3) have hybrid (or fusion) genes like those that have been proposed to underlie color anomaly. In some observers the long-wave hybrid genes contain a substantial amount of middle-wave sequence, e.g. five observers have hybrid long-wave genes that contain middle-wave sequences that include exon 4. Three of those five have the hybrid as their only long-wave gene, and thus have no other gene that could potentially encode a long-wave pigment. In these subjects, it is the hybrid gene that produces their normal long-wavelength-sensitive cone pigment. The high frequency of hybrid genes indicates that they are normal variant forms of the long-wave gene. Contrary to what is commonly believed, the introduction and the expression of hybrid genes is not sufficient to cause color vision defects.     

A perspective on disgust.

Approaches disgust as a food-related emotion and defines it as revulsion at the prospect of oral incorporation of offensive objects. These objects have contamination properties; if they contact an otherwise acceptable food, they tend to render it inedible. Issues considered include: the nature of the objects of disgust and why they are virtually all of animal origin, the meaning of oral incorporation, the belief that people take on the properties of the foods they eat, the nature of the contamination response and its relation to the laws of sympathetic magic (similarity and contagion), and the ontogeny of disgust, which is believed to develop during the 1st 8 yrs of life. The idea that feces, the universal disgust object, is also the 1st is explored, and the mechanisms for the acquisition of disgust are examined. Disgust is recommended as an easily studiable emotion, a model for cognitive–affective linkages, and a model for the acquisition of values and culture. (103 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Severity of color vision defects: electroretinographic (ERG), molecular and behavioral studies

Earlier research on phenotype/genotype relationships in color vision has shown imperfect predictability of color matching from the photopigment spectral sensitivities inferred from molecular genetic analysis. We previously observed that not all of the genes of the X-chromosome linked photopigment gene locus are expressed in the retina. Since sequence analysis of DNA does not necessarily reveal which of the genes are expressed into photopigments, we used ERG spectral sensitivities and adaptation measurements to assess expressed photopigment complement. Many deuteranomalous subjects had L, M, and L-M hybrid genes. The ERG results showed that M pigment is not present in measurable quantities in deutan subjects. Using these results to determine gene expression improved the correlations between inferred pigment separation and color matching. Furthermore, we found a subject who had normal L and M genes and normal proximal promoter sequences, yet he had a single photopigment (M) by ERG and tested as a protanope. These results demonstrate the utility of ERG measurements in studies of molecular genetics of color vision deficiencies, and further support the conclusion that not all genes are expressed in color deficient subjects. In particular, deuteranomaly requires a presently unknown mechanism of selective expression which excludes normal M genes and allows expression of L-M hybrid genes in one cone type, and the normal L in another.     

A perspective on thinking.

Research on general thinking abilities—productive, higher order, critical, and creative thinking—has progressed slowly compared with the rapid progress that has been made in the study of cognitive structures and procedures. As alternatives to currently prevailing assumptions, three framing assumptions for the study of thinking are proposed, involving situated cognition, personal and social epistemologies, and conceptual competence. Evidence consistent with these assumptions is outlined, and topics in the psychology of thinking are discussed in relation to the assumptions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)