Virginia Commonwealth University

About: Virginia Commonwealth University is a education organization based out in Richmond, Virginia, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 23822 authors who have published 49587 publications receiving 1787046 citations. The organization is also known as: VCU.

Cross-modal plasticity in specific auditory cortices underlies visual compensations in the deaf

Abstract: When the brain is deprived of input from one sensory modality, it often compensates with supranormal performance in one or more of the intact sensory systems. In the absence of acoustic input, it has been proposed that cross-modal reorganization of deaf auditory cortex may provide the neural substrate mediating compensatory visual function. We tested this hypothesis using a battery of visual psychophysical tasks and found that congenitally deaf cats, compared with hearing cats, have superior localization in the peripheral field and lower visual movement detection thresholds. In the deaf cats, reversible deactivation of posterior auditory cortex selectively eliminated superior visual localization abilities, whereas deactivation of the dorsal auditory cortex eliminated superior visual motion detection. Our results indicate that enhanced visual performance in the deaf is caused by cross-modal reorganization of deaf auditory cortex and it is possible to localize individual visual functions in discrete portions of reorganized auditory cortex.

Synthesis and Characterization of Porous Benzimidazole-Linked Polymers and Their Performance in Small Gas Storage and Selective Uptake

Abstract: Porous organic polymers containing nitrogen-rich building units are among the most promising materials for selective CO2 capture and separation which can have a tangible impact on the environment and clean energy applications. Herein we report on the synthesis and characterization of four new porous benzimidazole-linked polymers (BILPs) and evaluate their performance in small gas storage (H2, CH4, CO2) and selective CO2 binding over N2 and CH4. BILPs were synthesized in good yields by the condensation reaction between aryl-o-diamine and aryl-aldehyde building blocks. The resulting BILPs exhibit moderate surface area (SABET = 599–1306 m2 g–1), high chemical and thermal stability, and remarkable gas uptake and selectivity. The highest selectivity based on initial slope calculations at 273 K was observed for BILP-2: CO2/N2 (113) and CO2/CH4 (17), while the highest storage capacity was recorded for BILP-4: CO2 (24 wt % at 273 K and 1 bar) and H2 (2.3 wt % at 77 K and 1 bar). These selectivities and gas uptake...

What kinds of things are psychiatric disorders

Abstract: This essay explores four answers to the question 'What kinds of things are psychiatric disorders?' Essentialist kinds are classes whose members share an essence from which their defining features arise. Although elegant and appropriate for some physical (e.g. atomic elements) and medical (e.g. Mendelian disorders) phenomena, this model is inappropriate for psychiatric disorders, which are multi-factorial and 'fuzzy'. Socially constructed kinds are classes whose members are defined by the cultural context in which they arise. This model excludes the importance of shared physiological mechanisms by which the same disorder could be identified across different cultures. Advocates of practical kinds put off metaphysical questions about 'reality' and focus on defining classes that are useful. Practical kinds models for psychiatric disorders, implicit in the DSM nosologies, do not require that diagnoses be grounded in shared causal processes. If psychiatry seeks to tie disorders to etiology and underlying mechanisms, a model first proposed for biological species, mechanistic property cluster (MPC) kinds, can provide a useful framework. MPC kinds are defined not in terms of essences but in terms of complex, mutually reinforcing networks of causal mechanisms. We argue that psychiatric disorders are objectively grounded features of the causal structure of the mind/brain. MPC kinds are fuzzy sets defined by mechanisms at multiple levels that act and interact to produce the key features of the kind. Like species, psychiatric disorders are populations with central paradigmatic and more marginal members. The MPC view is the best current answer to 'What kinds of things are psychiatric disorders?'