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BACKGROUND: Schizophrenia (SZ) is most recognized by its psychotic symptoms, yet the cognitive deficits are more predictive of functional outcome and less responsive to treatment. The neuropathology underlying cognitive deficits remains elusive, but alterations in GABAergic interneurons are believed to play an essential role. One such alteration observed in human patients and animal models is a reduced number of parvalbumin (PV)-expressing interneurons in the prefrontal cortex (PFC). Such a loss of inhibitory GABAergic cells could disrupt the balance between excitation and inhibition (E/I) in ways that affect cognition. METHODS: In this study, we examine whether increasing the activity of the prefrontal PV cells that remain is sufficient to normalize E/I balance and rescue cognition in an animal model of SZ. To generate this model, we administer an NMDA antagonist (MK801) to adolescent rats, which reduces prefrontal PV cell number and recapitulates many of the behavioral endophenotypes of SZ. To increase the activity of remaining PV cells, we inject a virus into the PFC delivering a PV-promoter driven excitatory DREADD. Subsequent administration of CNO activates the DREADD, increasing the activity of transfected PV cells. We examine the effects of this intervention on E/I balance through whole cell patch clamp electrophysiology, and the effects on different aspects of cognition through the T-maze working memory task and the set shifting cognitive flexibility task. RESULTS: Our electrophysiological data indicate an elevated prefrontal E/I ratio in MK801-treated female rats, but not in male rats. The altered E/I balance in females is brought back to control levels by CNO activation of DREADD-expressing prefrontal PV cells. To further characterize sex differences, we compare PV cell counts in MK801- and saline-treated male and female rats. The electrophysiological findings in females are reflected in behavioral performance on two tests of cognition. MK801-treated female rats show impairments in working memory and cognitive flexibility compared to saline-treated controls, and performance improves when PV cell activity is increased. Specifically, a two-way mixed ANOVA of T-maze performance showed a significant main effect of group. As expected, the SZ model group performed significantly worse than the control group. Interestingly, the rescue group’s performance was not significantly different from the control group. A mixed two-way ANOVA analysis of the set shifting task showed significant main effects of group on rule acquisition. The SZ model group required more trials to learn the rules than controls. The rescue group acquired the task significantly faster than the SZ model group and was not significantly different from controls. When looking at the types of errors made, we see that the SZ model animals made more perseverative errors than both controls and rescue group animals, while rescue and control animals performed similarly. DISCUSSION: The partial rescue of working memory and the robust rescue of cognitive flexibility we observe suggest that upregulating the activity of PV interneurons that remain in SZ may works as a strategy for ameliorating prefrontal GABAergic deficits and cognitive impairments. This study examines the mechanisms underlying cognitive dysfunction in SZ, potentially pointing to effective novel therapeutics. We have validated the effectiveness of our rescue across cellular, electrophysiological, and behavioral dimensions. Future directions include further exploration of gender differences including adjustments to our MK801 model that may elicit E/I deficits in males.

Despite very strict wildlife protection acts in several countries and trading laws such as CITES, illegal trading and poaching of wildlife is still active mostly because of the use of their parts in Chinese medicinal products and ornaments. For successfully identifying wildlife and their parts, mitochondrial DNA sequencing is being used now-a-days. DNA bar coding using fragments of cytochrome b and cytochrome oxidase I genes are frequently utilized for mammalian species identification. This mini review describes some of the mtDNA sequences and STR markers used for mammalian species identification in the field of forensic wildlife along with the problems associated and their possible solutions.

Structural analysis of π-extended 7,7,8,8-tetracyano-p-quinodimethane (TCNQ)-based molecules reveal molecular and packing features which may help better understand the weak electron accepting features for these molecules compared with TCNQ, in solution (cyclic voltammetry measurements), while showing varying trends in thin solid films (photoinduced electron transfer measurements). On the basis of the current findings, we propose that unsymmetrical compounds in this series hold promise as good candidates for use in solar cell applications as their molecular features allow for better solid-state packing, a property likely conducive for better charge transport. Electron acceptor/donor pairs of compatible molecular shapes rather than the usually sought planar shapes may offer a route worth pursuing.

This paper explores how socio-economic, especially socio-religious affiliations, and demographic characteristics of individuals influence participation in higher education (HE). It argues that appropriate measures of ‘deficits’ in participation should inform the nature and scope of affirmative action. The analytical and policy relevance of distinguishing between stock and flow measures, the differences in eligibility for HE across groups are emphasized. After controlling for relevant factors, the ‘hierarchy of participation in higher education’ that emerges from detailed analysis suggests that deficits for some marginalized groups are not high enough to justify reservation for these groups on the basis of low participation.

Research and Control Laboratory, Bharat Aluminium Co. Ltd., Korba-495 684 C.M.D.P.o:college, Bilaspur-495 001 Manuscript received 3 October 1989, revised 2 April1991, accepted 6 May 1991 Extractive Spectrophotometric Determination of Vanadium with N-Benzyl-2-chlorobenzo-hydroxamic Acid &nbsp

N-Benzyl-2-naphthohydroxamic acid extracts vanadium(V) selectively and quantitatively into chloroform from 2–8.5M hydrochloric acid in the presence of Mo(VI), Zr(IV) and Ce(IV). The extraction takes place quickly and gives a stable reddish-violet extract which shows an absorption maximum at 505 nm with molar absorptivity of (5.34 ± 0.05) × 103 1.mole−1.cm−1. The optimum range for the determination is 2.2–7.4 ppm of vanadium(V) in the final solution. The method has been used for the determination of vanadium in steels.

This paper describes the design and implementation of the NUMAchine multiprocessor. As the market for CC-NUMA multiprocessors expands, this research project provides a timely architectural design and cost-effective prototype. The key to the successful implementation for our 48-processor prototype is the use of off-the-shelf components and programmable logic devices. Since this machine will serve a research vehicle for parallel software development, a number of hardware features to enhance experimentation have been included in the design.