Cochin University of Science and Technology

About: Cochin University of Science and Technology is a education organization based out in Kochi, Kerala, India. It is known for research contribution in the topics: Thin film & Natural rubber. The organization has 5382 authors who have published 7690 publications receiving 103827 citations. The organization is also known as: CUSAT & Cochin University.

Prediction of Indian Summer-Monsoon Onset Variability: A Season in Advance.

Abstract: Monsoon onset is an inherent transient phenomenon of Indian Summer Monsoon and it was never envisaged that this transience can be predicted at long lead times. Though onset is precipitous, its variability exhibits strong teleconnections with large scale forcing such as ENSO and IOD and hence may be predictable. Despite of the tremendous skill achieved by the state-of-the-art models in predicting such large scale processes, the prediction of monsoon onset variability by the models is still limited to just 2-3 weeks in advance. Using an objective definition of onset in a global coupled ocean-atmosphere model, it is shown that the skillful prediction of onset variability is feasible under seasonal prediction framework. The better representations/simulations of not only the large scale processes but also the synoptic and intraseasonal features during the evolution of monsoon onset are the comprehensions behind skillful simulation of monsoon onset variability. The changes observed in convection, tropospheric circulation and moisture availability prior to and after the onset are evidenced in model simulations, which resulted in high hit rate of early/delay in monsoon onset in the high resolution model.

Hypoglycemia induced changes in cholinergic receptor expression in the cerebellum of diabetic rats

Abstract: Glucose homeostasis in humans is an important factor for the functioning of nervous system. Hypoglycemia and hyperglycemia is found to be associated with central and peripheral nerve system dysfunction. Changes in acetylcholine receptors have been implicated in the pathophysiology of many major diseases of the central nervous system (CNS). In the present study we showed the effects of insulin induced hypoglycemia and streptozotocin induced diabetes on the cerebellar cholinergic receptors, GLUT3 and muscle cholinergic activity. Results showed enhanced binding parameters and gene expression of Muscarinic M1, M3 receptor subtypes in cerebellum of diabetic (D) and hypoglycemic group (D + IIH and C + IIH). α7nAchR gene expression showed a significant upregulation in diabetic group and showed further upregulated expression in both D + IIH and C + IIH group. AchE expression significantly upregulated in hypoglycemic and diabetic group. ChAT showed downregulation and GLUT3 expression showed a significant upregulation in D + IIH and C + IIH and diabetic group. AchE activity enhanced in the muscle of hypoglycemic and diabetic rats. Our studies demonstrated a functional disturbance in the neuronal glucose transporter GLUT3 in the cerebellum during insulin induced hypoglycemia in diabetic rats. Altered expression of muscarinic M1, M3 and α7nAchR and increased muscle AchE activity in hypoglycemic rats in cerebellum is suggested to cause cognitive and motor dysfunction. Hypoglycemia induced changes in ChAT and AchE gene expression is suggested to cause impaired acetycholine metabolism in the cerebellum. Cerebellar dysfunction is associated with seizure generation, motor deficits and memory impairment. The results shows that cerebellar cholinergic neurotransmission is impaired during hyperglycemia and hypoglycemia and the hypoglycemia is causing more prominent imbalance in cholinergic neurotransmission which is suggested to be a cause of cerebellar dysfunction associated with hypoglycemia.

Fast UV sensing properties of n-ZnO nanorods/p-GaN heterojunction

Abstract: n-type ZnO nanorods are vertically grown over p-type Mg:GaN substrate by simple hydrothermal process to form a p-GaN/n-ZnO nanorods heterojunction. The heterojunction showed good rectifying behavior. The defect states in the heterojunction are analyzed in detail using photoluminescence studies. The device response is studied for various biasing conditions and UV light pulse illumination frequencies. The present device has the fastest UV response on comparison with devices based on solution grown ZnO nanorods. The device showed reproducible results even after long exposure to room temperature and humidity environment.

Mesoscale simulation of an extreme rainfall event over Mumbai, India, using a high-resolution MM5 model

Abstract: Mesoscale models are essential for the accurate prediction of high-impact weather, such as severe thunderstorms, heavy rainfall events, mountain weather forecasting, cloudbursts and cyclones. An attempt has been made in the present study to simulate the heavy rainfall event that occurred during 26 July 2005 over Santa Cruz (19.20°N, 72.53°E) in Mumbai, India, using the Fifth-Generation NCAR/Penn State Mesoscale Model (MM5). The cloud-resolving mesoscale model with the right combination of the nesting domains, horizontal resolution and cloud parameterization schemes, is able to simulate the heavy rainfall event both qualitatively and quantitatively. The model results indicate the existence of an intense mesoscale vortex in the mid-troposphere during this heavy rainfall event. The localized heavy rainfall which occurred over Santa Cruz may possibly be due to the subsidence of the mid-tropospheric mesoscale vortex, superimposed on the active monsoon conditions over this region. Copyright © 2007 Royal Meteorological Society