Arijit Roy
Coventry University, Computer Science, Graduate Student
Terpinolene oxide, a monoterpene belonging to the p-menthane group, is easily derived from naturally abundant (R)-limonene. It was isomerized with montmorillonite clay catalyst to karahanaenone (2,2, 5-trimethylcyclohept-4-en-1-one) by... more
Terpinolene oxide, a monoterpene belonging to the p-menthane group, is easily derived from naturally abundant (R)-limonene. It was isomerized with montmorillonite clay catalyst to karahanaenone (2,2, 5-trimethylcyclohept-4-en-1-one) by ring enlargement. The enantiomers of the corresponding alcohol, karahanaenol (2,2, 5-trimethylcyclohept-4-en-1- ol), known for their individual organoleptic properties, were resolved through Pseudomonas cepacia lipase mediated enantiospecific alcoholysis of its acetate derivative.
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Precipitate growth kinetics can be modelled using a combination of Allen-Cahn and Cahn-Hilliard equations. In this paper, we describe one such phase field model which incorporates cubic anisotropy in interfacial energy as well as in... more
Precipitate growth kinetics can be modelled using a combination of Allen-Cahn and Cahn-Hilliard equations. In this paper, we describe one such phase field model which incorporates cubic anisotropy in interfacial energy as well as in atomic mobility to study the growth ki-netics of a β-phase precipitate growing from a supersaturated α-phase matrix. The model is implemented using a semi-implicit Fourier spectral technique. We show that the morphologies which result from atomic mobility anisotropy can be very different from those which result from interfacial energy anisotropy. We also show that the combined effect of both these anisotropies leads to very interesting microstructural features. Finally, we indicate the extension of these models to incorporate hexagonal anisotropies.
The present study was carried out with an aim to perform a prospective study to establish the role of sodium tetradecyl sulfate (3 %) (STDS) as a safe and effective sclerosant in the management of primary hydrocele. Sclerotherapy was... more
The present study was carried out with an aim to perform a prospective study to establish the role of sodium tetradecyl sulfate (3 %) (STDS) as a safe and effective sclerosant in the management of primary hydrocele. Sclerotherapy was performed with 3 % STDS on an outdoor basis. The amount of sclerosant injected depended on the amount of fluid drained. All patients were given prophylactic antibiotics. Patients were clinically reassessed at 1 week, 1 month, 3 months, and 6 months and earlier if complications occur. The data were analyzed using Statistical Package for Social Sciences Version 15.0. The data have been represented as frequencies and percentages. Chi-square test was used to compare the data. A total of 57 patients with primary vaginal hydrocele gave consent for being enrolled in the study. The age of patients ranged from 18 to 65 years with a mean age of 35.72 ± 13.18 years. The success rate at the end of the study was observed to be 84.2 %. As regards patient satisfaction, in present study, in a limited time period of follow up, all the patients who had a successful procedure were satisfied. Overall, sclerotherapy was observed to be a relatively cost-effective (including both direct and indirect costs) procedure with low complications, high satisfaction, and a high success rate within the limited period of follow-up.
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Spinocerebellar ataxias (SCAs) are hereditary, autosomal dominant progressive neurodegenerative disorders showing clinical and genetic heterogeneity. They are usually manifested clinically in the third to fifth decade of life although... more
Spinocerebellar ataxias (SCAs) are hereditary, autosomal dominant progressive neurodegenerative disorders showing clinical and genetic heterogeneity. They are usually manifested clinically in the third to fifth decade of life although there is a wide variability in the age of onset. More than 36 different types of SCAs have been reported so far and about half of them are caused by pathological expansion of the trinucleotide, Cytosine Alanine Guanine (CAG) repeat. The global prevalence of SCA is 0.3-2 per 100,000 population, SCA3 being the commonest variety worldwide, accounting for 20-50 per cent of all cases, though SCA 2 is generally considered as the commonest one in India. However, SCA6 has not been addressed adequately from India though it is common in the eastern Asian countries like, Japan, Korea and Thailand. The present study was undertaken to identify the prevalence of SCA6 in the city of Kolkata and the eastern part of India. 83 consecutive patients were recruited for the study of possible SCAs and their clinical features and genotype were investigated. 6 of the 83 subjects turned out positive for SCA6, constituting therefore, 13.33% of the patient pool. SCA6 is prevalent in the eastern part of India, though not as frequent as the other common varieties. Further community based studies are required in order to understand the magnitude of SCA6 in the eastern part, as well as in other regions of India.
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In the present study, an attempt has been made to evaluate the scope of enhancing wear resistance of austempered ductile iron (ADI) by laser surface melting (LSM) and laser surface hardening (LSH). A detailed study concerning... more
In the present study, an attempt has been made to evaluate the scope of enhancing wear resistance of austempered ductile iron (ADI) by laser surface melting (LSM) and laser surface hardening (LSH). A detailed study concerning microstructural evolution and mechanical properties ...
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The authors use a solid mechanics approach to investigate hydride formation and cracking in zirconium-niobium alloys used in the pressure tubes of CANDU nuclear reactors. In this approach, the forming hydride is assumed to be purely... more
The authors use a solid mechanics approach to investigate hydride formation and cracking in zirconium-niobium alloys used in the pressure tubes of CANDU nuclear reactors. In this approach, the forming hydride is assumed to be purely elastic and its volume dilation is accommodated by elasto-plastic deformation of the surrounding matrix material. The energetics of the hydride formation is revisited and
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Cognitive symptoms are common in advanced Parkinson's disease (PD). However, assessment of cognitive... more
Cognitive symptoms are common in advanced Parkinson's disease (PD). However, assessment of cognitive impairment is difficult in PD because of accompanying motor symptoms and the coexistence of nonmotor symptoms. Specific subdomains affected in the disease are not reflected in the conventional scales used for assessing cognition. This study was aimed at looking at the spectrum of cognitive impairment in the various phenotypes and stages of PD and the correlation of cognitive impairment with motor and nonmotor symptoms of PD. Fifty PD patients fulfilling the UK PD Society Brain Bank's criteria were selected after obtaining explicit consent. Patients were assessed clinically and by using various scales like Scales for Outcomes in PD-Cognition (SCOPA-COG), mini-mental state examination, and Beck's Depression Inventory and Scoring. The mean age was 58 years, 82% of the patients were male, and the mean modified Hoehn and Yahr staging was 2. The most commonly affected domains were memory and executive functioning. Cognitive impairment was more in those with late-onset disease, more advanced stage of disease, and in the postural instability and gait disorder (PIGD) subgroup. The cognitive function deteriorated with increasing age and duration of the illness. Significant correlation with cognitive impairment was obtained for the manifestations of increased motor disability, presence of coexistent psychotic symptoms and depression. Cognitive impairment was common among PD patients, and it was more prevalent with increasing duration of the disease, in older patients, in late-onset disease, and in the PIGD subgroup. Increasing motor disability and associated psychotic symptoms as well as depression significantly increased the cognitive impairment.
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... Since the discovery of electromigration (EM) phenomena in the 1960s, the theory of ... With the various interconnect system developed as integrated circuit (IC) technology progresses, and ... under driving forces through various... more
... Since the discovery of electromigration (EM) phenomena in the 1960s, the theory of ... With the various interconnect system developed as integrated circuit (IC) technology progresses, and ... under driving forces through various diffusion paths in the metal interconnection during EM ...
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In this paper, we present quantitative analyses of the impact of Joule heating on the package level electromigration (EM) test of copper dual damascene (DD) interconnects with linewidths of 0.28 and 0.7 μm. A total of 120 samples are... more
In this paper, we present quantitative analyses of the impact of Joule heating on the package level electromigration (EM) test of copper dual damascene (DD) interconnects with linewidths of 0.28 and 0.7 μm. A total of 120 samples are tested with a maximum current density of 8 MA/cm2. It is found that high test current density has a negligible impact on the estimation of activation energy and offers an opportunity to shorten the test time. However, the current density exponent is found to be a strong function of test current density, especially for interconnects with a larger linewidth. Correction due to Joule heating on the estimation of the current density exponent is described.
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Research Interests: Biochemistry, Physiology, Chemistry, RNA, Structural Dynamics, and 28 moreGene regulation, Body, Vitamin D, Membrane Proteins, Gene expression, Estrogen Receptor, Antibodies, Vitamin D receptor, Hormones, Rodents, Nucleic Acids, Proteins, Cytochrome oxidase, Cloning, Gene Structure, Populations, Digestive System, Receptors, Peptide hormones, Sexual Differentiation, Structure activity Relationship, Gene Family, Ligands, Binding Site, Biochemistry and cell biology, Nuclear Localization, Globulins, and DNA sequence
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Myoclonic dystonia refers to a clinical syndrome characterized by rapid jerky movements along with dystonic posturing of the limbs. Clinically, it is characterized by sudden, brief, electric shock-like movements, mostly involving the... more
Myoclonic dystonia refers to a clinical syndrome characterized by rapid jerky movements along with dystonic posturing of the limbs. Clinically, it is characterized by sudden, brief, electric shock-like movements, mostly involving the upper extremities, shoulders, neck and trunk. Characteristically, the movements wane with consumption of small dose of alcohol in about 50% of cases. Additionally, dystonic contractions are observed in most of the patients in the affected body parts and some patients may exhibit cervical dystonia or graphospasm as well. It may manifest as an autosomal dominant condition or sometimes, as a sporadic entity, though there are doubts whether these represent cases with reduced penetrance. The condition is usually treated with a combination of an anticholinergic agent like, benztropine, pimozide and tetrabenazine. We report one sporadic case and one familial case where the father and the son are affected. The cases were collected from the Movement Disorders Clinic of Bangur Institute of Neurosciences, Kolkata, West Bengal in a period of ten months. Myoclonic dystonia is a rare condition and to the best of our knowledge, this series is the first one reported from our country. Videos of the patients are also provided with the article.
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To assess the visuospatial function in different types of dementia with the visual object and space perception (VOSP) battery and to relate the degree of visuospatial dysfunction with different types and stages of dementia. A sample of 53... more
To assess the visuospatial function in different types of dementia with the visual object and space perception (VOSP) battery and to relate the degree of visuospatial dysfunction with different types and stages of dementia. A sample of 53 participants with dementia and equal number of age-, sex-, and education-matched controls were recruited for the study. Participants were evaluated for visuospatial skill using VOSP test battery. The scores of dementia patients were compared with controls and within dementia cohort scores were compared based on stage of dementia. The dementia group scored low in all of the subtests of the VOSP battery in comparison to controls. Alzheimer's disease (AD), dementia of Lewy bodies (DLB), and vascular dementia (VaD) patients performed more poorly than controls in all subtests examining object perception and space perception. The three semantic variants of frontotemporal dementia (FTD) patients scored low in all four subtests of object perception, whereas behavioral variant FTD (bvFTD) patients performed normally. The scores deteriorated with the advancement of dementia in all patients from the dementia groups. Visuospatial function is significantly impaired in dementia patients particularly in AD, DLB, and VaD patients from the beginning, and the impairment is severe in advanced disease stages.
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The efficacy of pentoxifylline--a haemorrheologic agent along with aspirin--an analgesic agent was evaluated in the amelioration of the tissue damage due to experimentally induced frostbite in 5 groups (20 each) of rats with body weights... more
The efficacy of pentoxifylline--a haemorrheologic agent along with aspirin--an analgesic agent was evaluated in the amelioration of the tissue damage due to experimentally induced frostbite in 5 groups (20 each) of rats with body weights ranging between 175 and 200 g. Frostbite was produced experimentally in the hind limbs by exposing the animals to -15 +/- 1 degrees C for 1 h using the harness technique, with simultaneous recording of rectal and environmental temperatures. The degree of tissue damage was assessed on the basis of tissue necrosis after 15 days. Administration of pentoxifylline (40 mg/kg bw) 30 min before and 30 min after the cold exposure followed by two doses of the same daily for the next 5 days along with aspirin (5 mg/kg bw) twice daily for the same duration only after cold exposure, resulted in significant improvement in the degree of tissue preservation. The findings of this preliminary study have brought to light the potential usefulness of these drugs in the ...