51 research outputs found
A Foot in Both Worlds: Asian Americans' Perceptions of Asian, White, and Racially Ambiguous Faces
Past research on racial perception has often focused on responses from White participants, making it difficult to determine the role of perceiver race in the perception of others. Similarly, studies examining perceptions of individuals whose racial category membership is unclear have not systematically examined responses from non-Whites. This was addressed by showing Asian participants pictures of Whites, Asians, and racially ambiguous White-Asian faces. Event-related potentials were recorded to measure early attention responses. Participants initially oriented more to outgroup White than ingroup Asian or racially ambiguous faces. Shortly after that, they showed sensitivity to the racial context in which the faces were presented, more deeply processing ingroup Asian and racially ambiguous faces when they were seeing lots of other Asians, but more deeply processing outgroup White and racially ambiguous faces when they were seeing lots of other Whites. Still later, responses were more sensitive to the objective physical properties of the faces, with racially ambiguous faces differentiated from both Whites and Asians. These results demonstrate the fluidity of racial processing, and when compared to responses obtained from White participants, show how perceiver race and racial context influences attention to racial cues
Scabies Mite Peritrophins Are Potential Targets of Human Host Innate Immunity
The gut of most invertebrates is lined by a protective layer of chitin and glycoproteins, often designated as a peritrophic matrix. Previous research suggests that it forms a barrier that may protect the midgut epithelium from abrasive food particles and pathogens. Parasitic invertebrates ingesting vertebrate plasma have evolved additional strategies to protect themselves from hazardous host molecules consumed during feeding. An important part of the immediate defense in vertebrate plasma is complement-mediated killing. The Complement system is a complex network of more than 35 proteins present in human plasma that results in killing of foreign cells including the gut epithelial cells of a feeding parasite. Recently we found that scabies mites, who feed on skin containing plasma, produce several proteins that inhibit human complement within the mite gut. The mites excrete these molecules into the upper epidermis where they presumably also inhibit complement activity. Mite gut antigens that initially trigger the complement cascade have not been identified previously. Obvious possible targets of complement attack within the mite gut could be peritrophins. Our study describes the first peritrophin identified in scabies mites and indicates a possible role in complement activation
Towards a new phenotype for tick resistance in beef and dairy cattle:a review
About 80% of the world's cattle are affected by ticks and tick-borne diseases, both of which cause significant production losses. Cattle host resistance to ticks is the most important factor affecting the economics of tick control, but it is largely neglected in tick-control programs due to technical difficulties and costs associated with identifying individual-animal variation in resistance. The present paper reviews the scientific literature to identify factors affecting resistance of cattle to ticks and the biological mechanisms of host tick resistance, to develop alternative phenotype(s) for tick resistance. If new cost-effective phenotype(s) can be developed and validated, then tick resistance of cattle could be genetically improved using genomic selection, and incorporated into breeding objectives to simultaneously improve cattle productive attributes and tick resistance. The phenotype(s) could also be used to improve tick control by using cattle management. On the basis of the present review, it is recommended that three possible phenotypes (haemolytic analysis measures of skin hypersensitivity reactions simplified artificial tick infestations) be further developed to determine their practical feasibility for consistently, cost-effectively and reliably measuring cattle tick resistance in thousands of individual animals in commercial and smallholder farmer herds in tropical and subtropical areas globally. During evaluation of these potential new phenotypes, additional measurements should be included to determine the possibility of developing a volatile-based resistance phenotype, to simultaneously improve cattle resistance to both ticks and biting flies. Because the current measurements of volatile chemistry do not satisfy the requirements of a simple, cost-effective phenotype for use in commercial cattle herds, consideration should also be given to inclusion of potentially simpler measures to enable indirect genetic selection for volatile-based resistance to ticks
Decision ambiguity is mediated by a late positive potential originating from cingulate cortex
Electro-cortical implicit race bias does not vary with participants' race or sex
Earlier research found evidence for electro-cortical race bias towards black target faces in white American participants irrespective of the task relevance of race. The present study investigated whether an implicit race bias generalizes across cultural contexts and racial in- and out-groups. An Australian sample of 56 Chinese and Caucasian males and females completed four oddball tasks that required sex judgements for pictures of male and female Chinese and Caucasian posers. The nature of the background (across task) and of the deviant stimuli (within task) was fully counterbalanced. Event-related potentials (ERPs) to deviant stimuli recorded from three midline sites were quantified in terms of mean amplitude for four components: N1, P2, N2 and a late positive complex (LPC; 350–700 ms). Deviants that differed from the backgrounds in sex or race elicited enhanced LPC activity. These differences were not modulated by participant race or sex. The current results replicate earlier reports of effects of poser race relative to background race on the LPC component of the ERP waveform. In addition, they indicate that an implicit race bias occurs regardless of participant's or poser's race and is not confined to a particular cultural context
Survival of mouse embryos frozen-thawed slowly or rapidly in the presence of various cryoprotectants
Associations of Neospora caninum seropositivity with environment and management in Danish dairy herds
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