The pathophysiology of restricted repetitive behavior

Restricted, repetitive behaviors (RRBs) are heterogeneous ranging from stereotypic body movements to rituals to restricted interests. RRBs are most strongly associated with autism but occur in a number of other clinical disorders as well as in typical development. There does not seem to be a category of RRB that is unique or specific to autism and RRB does not seem to be robustly correlated with specific cognitive, sensory or motor abnormalities in autism. Despite its clinical significance, little is known about the pathophysiology of RRB. Both clinical and animal models studies link repetitive behaviors to genetic mutations and a number of specific genetic syndromes have RRBs as part of the clinical phenotype. Genetic risk factors may interact with experiential factors resulting in the extremes in repetitive behavior phenotypic expression that characterize autism. Few studies of individuals with autism have correlated MRI findings and RRBs and no attempt has been made to associate RRB and post-mortem tissue findings. Available clinical and animal models data indicate functional and structural alterations in cortical-basal ganglia circuitry in the expression of RRB, however. Our own studies point to reduced activity of the indirect basal ganglia pathway being associated with high levels of repetitive behavior in an animal model. These findings, if generalizable, suggest specific therapeutic targets. These, and perhaps other, perturbations to cortical basal ganglia circuitry are mediated by specific molecular mechanisms (e.g., altered gene expression) that result in long-term, experience-dependent neuroadaptations that initiate and maintain repetitive behavior. A great deal more research is needed to uncover such mechanisms. Work in areas such as substance abuse, OCD, Tourette syndrome, Parkinson’s disease, and dementias promise to provide findings critical for identifying neurobiological mechanisms relevant to RRB in autism. Moreover, basic research in areas such as birdsong, habit formation, and procedural learning may provide additional, much needed clues. Understanding the pathophysioloy of repetitive behavior will be critical to identifying novel therapeutic targets and strategies for individuals with autism

Preparation and characterization of hollow glass microspheres (HGMs) for hydrogen storage using urea as a blowing agent

Hollow glass microspheres (HGMs) are unique class of porous material that can be used for hydrogen storage. They are finely dispersed and free flowing powder having microsphere diameter, 10-200 mu m and wall thickness, 0.5-2 mu m. In this report, we present the preparation of HGMs from glass frits using air-acetylene flame spheroidisation method. Urea was incorporated in the feed glass as a blowing agent to get porous walled HGMs. Effect of concentration of urea in the feed glass on the development of pores on HGMs wall was investigated. It was observed that, the porosity of the HGMS walls increased with the increase in urea content in the feed glass. Characterization of HGMs prepared was done using FE-SEM, ESEM, FTIR and XRD techniques. The spherical nature and the morphology of the HGMs samples prepared were confirmed using FE-SEM, while the pore diameter and the porosity of the samples was observed in the ESEM images. Hydrogen adsorption experiments were carried out at room temperature (RT) and 200 degrees C at 10 bar pressure, for 5 h for all the HGMs samples prepared. The HGMs prepared with 2% urea showed large number of micro/nano pores and it showed a hydrogen storage capacity of 2.3 wt.% at 200 degrees C and 10 bar pressure. The hydrogen adsorption on HGMs at RT and 10 bar pressure was lower than that observed at 200 degrees C and 10 bar pressure. (C) 2014 Elsevier B.V. All rights reserved

Effect of Co loading on the hydrogen storage characteristics of hollow glass microspheres (HGMs)

The use of hydrogen as a fuel either direct combustion in an IC engine or for power generation in fuel cells continues to be a topic of significant interest. Developing and popularizing fuel cells for vehicular or other stationary applications depends upon the availability of safe and reliable hydrogen storage method. The greatest challenge as of now in this regard is the production of a light weight, nontoxic and easily transportable material which can store hydrogen. World-wide research is being conducted on developing newer materials for hydrogen storage. Hollow glass microspheres (HGMs) can be considered to be a potential hydrogen carrier which can store and deliver hydrogen for energy release applications. In this paper, we are reporting the preparation and characterization of cobalt loaded HGMs from amber glass powder for hydrogen storage applications. The feed glass powder with different percentage of cobalt loading was prepared by soaking and drying the feed glass powder in required amount of cobalt nitrate hexahydrate solution. Further, the dried feed glass powder was flame spheroidised to get cobalt loaded HGMs. Characterizations of all the HGMs samples were done using SEM, FTIR and XRD techniques. Hydrogen adsorptions on all the samples were done for 10 bar pressure at room temperature and 200 degrees C for 5 h. The results showed that the hydrogen adsorption capacity on these samples increased with increase in cobalt wt% from 0.2 to 2.0%. The hydrogen storage capacity of HACo2 was found to 2.32 wt% for 10 bar pressure at 200 degrees C. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved

sj-docx-1-pic-10.1177_09544062231184396 – Supplemental material for Artificial Neural Network prediction of forming limit diagram for directionally-rolled, size scaled copper strips

Supplemental material, sj-docx-1-pic-10.1177_09544062231184396 for Artificial Neural Network prediction of forming limit diagram for directionally-rolled, size scaled copper strips by SP Sundar Singh Sivam, N Harshavardhana and R Rajendran in Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science</p