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Biswas M, Chatterjee A, Ghosh SK, Dasgupta S, Ghosh K, Ganguly PK. Prevalence, types, clinical associations, and determinants of peripheral neuropathy in rheumatoid patients. Ann Indian Acad Neurol 2011; 14:194-7. [PMID: 22028533 PMCID: PMC3200043 DOI: 10.4103/0972-2327.85893] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2010] [Revised: 02/19/2011] [Accepted: 03/09/2011] [Indexed: 11/15/2022] Open
Abstract
Background: Rheumatoid arthritis is a multi-system autoimmune disorder predominantly involving multiple small and large joints along with certain extra-articular manifestations. The presence of peripheral neuropathy in patients with rheumatoid arthritis contributes significantly to the functional limitation in patients with rheumatoid arthritis. Objectives: To study the prevalence, types, and determinants of peripheral neuropathy in patients with rheumatoid arthritis. Materials and Methods: We studied 74 patients with rheumatoid arthritis of at least 2 year duration for the presence of peripheral neuropathy both clinically and electrophysiologically. The data obtained were entered into a database and continuous variables were analyzed using the Student t test and categorical variables were analyzed using the chi-square test. Results: Peripheral neuropathy was detected in 39.19% (29 out of 74 patients) patients on electrophysiologic testing and 82.76% (24 out of 29 patients) of the patients were asymptomatic. There was significant association between the presence of peripheral neuropathy and disease duration and rheumatoid factor positivity by the latex agglutination method. Sensory neuropathy was the most common form detected. Conclusions: Our study shows that subclinical peripheral neuropathy particularly sensory neuropathy which is not related to disease severity is very common in patients with prolonged disease duration.
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Keidar M, Walk R, Shashurin A, Srinivasan P, Sandler A, Dasgupta S, Ravi R, Guerrero-Preston R, Trink B. Cold plasma selectivity and the possibility of a paradigm shift in cancer therapy. Br J Cancer 2011; 105:1295-301. [PMID: 21979421 PMCID: PMC3241555 DOI: 10.1038/bjc.2011.386] [Citation(s) in RCA: 338] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Background: Plasma is an ionised gas that is typically generated in high-temperature laboratory conditions. However, recent progress in atmospheric plasmas has led to the creation of cold plasmas with ion temperature close to room temperature. Methods: Both in-vitro and in-vivo studies revealed that cold plasmas selectively kill cancer cells. Results: We show that: (a) cold plasma application selectively eradicates cancer cells in vitro without damaging normal cells; and (b) significantly reduces tumour size in vivo. It is shown that reactive oxygen species metabolism and oxidative stress responsive genes are deregulated. Conclusion: The development of cold plasma tumour ablation has the potential of shifting the current paradigm of cancer treatment and enabling the transformation of cancer treatment technologies by utilisation of another state of matter.
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Dasgupta S, Tyler SC, Grossman ED. Co-localization of human posterior STS during biological motion, face and social perception. J Vis 2011. [DOI: 10.1167/11.11.629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Tyler SC, Dasgupta S, Battelli L, Grossman ED. Lateralized Temporal Parietal Junction (TPJ) activity during temporal order judgment tasks. J Vis 2011. [DOI: 10.1167/11.11.264] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Mukhopadhyay A, Dasgupta S, Mukhopadhyay S, Bose CK, Sarkar S, Gharami F, Koner S, Basak J, Roy UK. Imatinib mesylate therapy in patients of chronic myeloid leukemia with Philadelphia chromosome positive: an experience from eastern India. Indian J Hematol Blood Transfus 2011; 28:82-8. [PMID: 23730014 DOI: 10.1007/s12288-011-0108-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Accepted: 08/25/2011] [Indexed: 12/24/2022] Open
Abstract
Imatinib inhibits constitutively active BCR-ABL tyrosine kinase of chronic myeloid leukemia (CML). In a long term study it was found superior to interferon alfa plus cytarabine for newly diagnosed CML in the chronic phase. However, till date there is no major study to evaluate eastern Indian CML patients treated with imatinib mesylate. The aim of our study was to see the efficacy, tolerability, toxicity and safety of imatinib in eastern Indian subset of CML population. The present study enrolled 831 patients with CML out of which 197 were excluded due to various reasons of noncompliance, death and not being fit to receive the drug. The rest, 634 (76% of total enrolled) were selected for the evaluation. In the beginning of the study, 603 patients were in chronic phase, 27 in accelerated phase and 4 patients in blast crisis phase. Among 634 patients, 280 patients (44%) received previously either interferon alpha or hydroxyurea and other 354 patients (56%) were previously untreated. Complete hematological remission and major cytogenetic response were 91 and 67%, respectively after 1 year of treatment. Complete molecular remission was 35% after 1 year of treatment. Sixty-four patients (10.1%) were resistant to imatinib mesylate in 5 years. The disease free and overall survival at 60 months were 72.2 and 76.1% respectively. After 60 months of follow up, continuous treatment of chronic phase CML with imatinib as initial therapy was found to be safe and able to induce durable responses in a high proportion of patients.
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Wagstaff J, Hawkins RE, Nathan PD, Sarda SP, Vekeman F, Korves C, Dasgupta S, O'Mara S, Fitton S, Hayers J, Tham C, Luka A, Wei R, Mykletun A, Neary M, Duh MS. Sunitinib (SU) treatment (trx) patterns and toxicity in patients (pts) with advanced renal cell carcinoma (RCC) in United Kingdom (UK). J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.e15150] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Mallik S, Mandal PK, Chatterjee C, Ghosh P, Manna N, Chakrabarty D, Bagchi SN, Dasgupta S. Assessing cold chain status in a metro city of India: an intervention study. Afr Health Sci 2011; 11:128-133. [PMID: 21572868 PMCID: PMC3092313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023] Open
Abstract
BACKGROUND Cold chain maintenance is an essential activity to maintain the potency of vaccines and to prevent adverse events following immunization. One baseline study highlighted the unsatisfactory cold chain status in city of Kolkata in India. OBJECTIVES To assess the changes which occurred in the cold chain status after the intervention undertaken to improve the status and also to assess the awareness of the cold chain handlers regarding cold chain maintenance. METHODS Intervention consisted of reorganization of cold chain points and training of health manpower in Kolkata Municipal area regarding immunization and cold chain following the guidelines as laid by Govt of India. Reevaluation of cold chain status was done at 20 institutions selected by stratified systematic random sampling after the intervention. The results were compared with baseline survey. RESULTS Significant improvement had been observed in correct placing of cold chain equipment, maintenance of stock security, orderly placing of ice packs, diluents and vaccines inside the equipment, temperature recording and maintenance. But awareness and skill of cold chain handlers regarding basics of cold chain maintenance was not satisfactory. CONCLUSIONS The success of intervention included significant improvement of cold chain status including creation of a designated cold chain handler. The gaps lay in non-availability of non-electrical cold chain equipment and separate cold chain room, policy makers should stress. Cold chain handlers need reorientation training regarding heat & cold sensitive vaccines, preventive maintenance and correct contingency plan.
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Roy S, Basu S, Dasgupta S, Singh AK, Viswanathan R. Carbapenem resistance in Acinetobacter baumannii isolated from blood of neonates with sepsis. Indian J Med Microbiol 2011; 28:416-7. [PMID: 20966591 DOI: 10.4103/0255-0857.71814] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Anderson B, Cao M, Dasgupta S, Morse A, Yu C. Maintaining a directed, triangular formation of mobile autonomous agents. COMMUNICATIONS IN INFORMATION AND SYSTEMS 2011. [DOI: 10.4310/cis.2011.v11.n1.a1] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Dasgupta S, Ng V. Which Clustering Do You Want? Inducing Your Ideal Clustering with Minimal Feedback. J ARTIF INTELL RES 2010. [DOI: 10.1613/jair.3003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
While traditional research on text clustering has largely focused on grouping documents by topic, it is conceivable that a user may want to cluster documents along other dimensions, such as the author's mood, gender, age, or sentiment. Without knowing the user's intention, a clustering algorithm will only group documents along the most prominent dimension, which may not be the one the user desires. To address the problem of clustering documents along the user-desired dimension, previous work has focused on learning a similarity metric from data manually annotated with the user's intention or having a human construct a feature space in an interactive manner during the clustering process. With the goal of reducing reliance on human knowledge for fine-tuning the similarity function or selecting the relevant features required by these approaches, we propose a novel active clustering algorithm, which allows a user to easily select the dimension along which she wants to cluster the documents by inspecting only a small number of words. We demonstrate the viability of our algorithm on a variety of commonly-used sentiment datasets.
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Nath RK, Dasgupta S, Ghosh S, Mitra A, Panda AK. Spectral Studies on the Binding Behavior of Cationic Dyes and Surfactants with Bacterial Polysaccharide ofKlebsiellaK43. J DISPER SCI TECHNOL 2010. [DOI: 10.1080/01932690903269586] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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87
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Dasgupta S, Pyles J, Grossman E. Multi-voxel pattern analysis (MVPA) of the STS during biological motion perception. J Vis 2010. [DOI: 10.1167/10.7.789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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88
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Dasgupta S, Ghosh S, Sengupta SG, Sarkar R. Tubo-ovarian Actinomycosis: a case report with brief review of literature. ACTA ACUST UNITED AC 2010. [PMID: 22918075 DOI: 10.4103/0019-5359.99872] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Pelvic actinomycosis is an uncommon condition, often associated with the use of intrauterine contraceptive device (IUCD). Pelvic actinomycosis is rare accounting for 3% of all human actinomycotic infections. Ovarian actinomycosis is even rarer. Here, we present a 24-year-old woman using an IUCD for 3 1 / 2 years with right-sided adnexal mass, which was diagnosed postoperatively as tubo-ovarian actinomycosis. Many times, an appropriate management is overlooked or delayed due to its non-specific and variable clinical and radiological features. Sometimes, it can even mimic an advanced pelvic malignancy. Therefore, the gynecologist should consider the possibility of this infection to spare the patient from morbidity of radical surgical procedure.
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Dasgupta S, Roy B, Tandon V. Ultrastructural alterations of the tegument of Raillietina echinobothrida treated with the stem bark of Acacia oxyphylla (Leguminosae). JOURNAL OF ETHNOPHARMACOLOGY 2010; 127:568-571. [PMID: 19854257 DOI: 10.1016/j.jep.2009.10.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2008] [Revised: 09/14/2009] [Accepted: 10/14/2009] [Indexed: 05/28/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE The stem bark of Acacia oxyphylla Graham ex Bentham is used as an anthelmintic by the natives of Mizoram (North-East India). AIM OF THE STUDY The present study was performed to evaluate whether or not the plant-derived components caused any ultrastructural changes in the tegumental interface of the parasite. MATERIALS AND METHODS The test parasite Raillietina echinobothrida, the cestode of domestic fowl, was exposed to the ethanolic crude extract and acetone fraction of stem bark of Acacia oxyphylla for varying concentrations and time duration and processed for transmission electron microscopy as soon as paralysis set in the treated parasites. RESULTS Treatment with crude alcoholic extract and its acetone fraction revealed complete inactivation and flaccid paralysis of the cestode, which was soon followed by death. The treated parasites also exhibited intense vacuolization of the tegumental layers along with complete disorganization and/or erosion of microtriches. CONCLUSIONS Considerable structural alterations in the treated parasites are suggestive of an efficient vermicidal activity of the Acacia oxyphylla stem bark-derived botanicals against cestodes.
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Navarrete A, Dasgupta S, Delignat S, Caligiuri G, Christophe OD, Bayry J, Nicoletti A, Kaveri SV, Lacroix-Desmazes S. Splenic marginal zone antigen-presenting cells are critical for the primary allo-immune response to therapeutic factor VIII in hemophilia A. J Thromb Haemost 2009; 7:1816-23. [PMID: 19682235 DOI: 10.1111/j.1538-7836.2009.03571.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Alloimmune responses to intravenously administered protein therapeutics are the most common cause of failure of replacement therapy in patients with defective levels of endogenous proteins. Such a situation is encountered in some patients with hemophilia A, who develop inhibitory anti-factor (F)VIII alloantibodies after administration of FVIII to treat hemorrhages. OBJECTIVES The nature of the secondary lymphoid organs involved in the initiation of immune responses to human therapeutic has not been studied. We therefore investigated this in the case of FVIII, a self-derived exogenous protein therapeutic. METHODS The distribution of intravenously administered FVIII was followed after FVIII-deficient mice were injected with radiolabeled FVIII and using immunohistochemistry. The role of the spleen and antigen-presenting cells (APC) in the onset of the anti-FVIII immune response was analyzed upon splenectomy or treatment of the mice with APC-depleting compounds. RESULTS FVIII preferentially accumulated in the spleen at the level of metallophilic macrophages in the marginal zone (MZ). Surgical removal of the spleen or selective in vivo depletion of macrophages and CD11c-positive CD8 alpha-negative dendritic cells resulted in a drastic reduction in anti-FVIII immune responses. CONCLUSIONS Using FVIII-deficient mice as a model for patients with hemophilia A, and human pro-coagulant FVIII as a model for immunogenic self-derived protein therapeutics, our results highlight the importance of the spleen and MZ APCs in the initiation of immune responses to protein therapeutics. Identification of the receptors implicated in retention of protein therapeutics in the MZ may pave the way towards novel strategies aimed at reducing their immunogenicity.
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Chakraborty S, Sengupta R, Dasgupta S, Mukhopadhyay R, Bandyopadhyay S, Joshi M, Ameta SC. Synthesis and characterization ofin situsodium-activated and organomodified bentonite clay/styrene-butadiene rubber nanocomposites by a latex blending technique. J Appl Polym Sci 2009. [DOI: 10.1002/app.30146] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Dasgupta S, Krekelberg B. Interactions between Speed and Contrast Tuning in Human Visual Cortex. Neuroimage 2009. [DOI: 10.1016/s1053-8119(09)70655-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Dasgupta S, Reddy BM. Present status of understanding on the genetic etiology of polycystic ovary syndrome. J Postgrad Med 2009; 54:115-25. [PMID: 18480528 DOI: 10.4103/0022-3859.40778] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Polycystic ovary syndrome (PCOS) is the most common endocrinopathy in women of reproductive age with a prevalence of approximately 7-10% worldwide. PCOS reflects multiple potential aetiologies and variable clinical manifestations. This syndrome is characterized by serious health implications such as diabetes, coronary heart diseases and cancer and also leads to infertility. PCOS can be viewed as a heterogeneous androgen excess disorder with varying degrees of reproductive and metabolic abnormalities determined by the interaction of multiple genetic and environmental factors. In this paper, we have attempted a comprehensive review of primarily molecular genetic studies done so far on PCOS. We have also covered the studies focusing on the environmental factors and impact of ethnicity on the presentation of this syndrome. A large number of studies have been attempted to understand the aetiological mechanisms behind PCOS both at the clinical and molecular genetic levels. In the Indian context, majority of the PCOS studies have been confined to the clinical dimensions. However, a concrete genetic mechanism behind the manifestation of PCOS is yet to be ascertained. Understanding of this complex disorder requires comprehensive studies incorporating relatively larger homogenous samples for genetic analysis and taking into account the ethnicity and the environmental conditions of the population/cohort under study. Research focused on these aspects may provide better understanding on the genetic etiology and the interaction between genes and environment, which may help develop new treatment methods and possible prevention of the syndrome.
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Das S, Dasgupta S, Biswas A, Abraham A, Konar A. On Stability of the Chemotactic Dynamics in Bacterial-Foraging Optimization Algorithm. ACTA ACUST UNITED AC 2009. [DOI: 10.1109/tsmca.2008.2011474] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Dasgupta S, Nath RK, Biswas S, Mitra A, Panda AK. Interactions of bacterial polysaccharides with cationic dyes: physicochemical studies. INDIAN JOURNAL OF BIOCHEMISTRY & BIOPHYSICS 2009; 46:192-197. [PMID: 19517998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Capsular polysaccharides (SPS) are an integral component of gram-negative bacteria, and also have potential use as vaccine. In this paper, interactions of SPS isolated from Klebsiella strains K20 and K51 with cationic dyes pinacyanol chloride (PCYN) and acridine orange (AO) were studied by absorbance and fluorescence measurements. Both the polysaccharides having glucuronic acid as the potential anionic site induced strong metachromasy (blue shift approximately 100 nm) in the PCYN. The spectral changes were studied at different polymer/dye molar ratios (P/D = 0-40). A complete reversal of metachromasy was observed upon addition of co-solvents, suggesting the breakaway of dye molecules from the biopolymer matrix. Binding constant, changes in free energy, enthalpy and entropy of the dye polymer complex were also computed from the spectral data at different temperatures to reveal the nature of the interaction. Quenching of fluorescence of AO by the polymers and the incorporated mechanisms were also explored.
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Dasgupta S, Wheeler D, Huq M, Khaliquzzaman M. Improving indoor air quality for poor families: a controlled experiment in Bangladesh. INDOOR AIR 2009; 19:22-32. [PMID: 19191925 DOI: 10.1111/j.1600-0668.2008.00558.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
UNLABELLED The World Health Organization's 2004 Global and Regional Burden of Disease Report estimates that acute respiratory infections from indoor air pollution (pollution from burning wood, animal dung, and other bio-fuels) kill a million children annually in developing countries, inflicting a particularly heavy toll on poor families in South Asia and Africa. This paper reports on an experiment that studied the use of different fuels in conjunction with different combinations of construction materials, space configurations, cooking locations, and household ventilation practices (use of doors and windows) as potentially-important determinants of indoor air pollution. Results from controlled experiments in Bangladesh were analyzed to test whether changes in these determinants can have significant effects on indoor air pollution. Analysis of the data shows, for example, that pollution from the cooking area is transported into living spaces rapidly and completely. Furthermore, it is important to factor in the interaction between outdoor and indoor air pollution. Hence, the optimal cooking location should take 'seasonality' in account. Among fuels, seasonal conditions seem to affect the relative severity of pollution from wood, dung, and other biomass fuels. However, there is no ambiguity about their collective impact. All are far dirtier than clean (LPG and Kerosene) fuels. The analysis concludes that if cooking with clean fuels is not possible, then building the kitchen with permeable construction material and providing proper ventilation in cooking areas will yield a better indoor health environment. PRACTICAL IMPLICATIONS Several village-level measures could significantly reduce IAP exposure in Bangladesh. All would require arrangements and the assert of male heads-of-household: negotiated bulk purchases of higher cost, cleaner fuels; purchase of more fuel-efficient stoves; peripheral location of cooking facilities; building the kitchen with permeable construction material; rotation of women in cooking roles, to reduce their exposure; and ventilation of smoke through a stack tall enough to disperse smoke over a relatively broad area. It is expected that village men and women will agree to these measures if they become convinced that IAP poses a serious risk to health, and their actions will significantly reduce the risk. The keys to success are effective public education about the sources and risks of IAP, and financial and technical assistance for changes in cooking arrangements.
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Purkait MK, Dasgupta S, De S. Precipitation of cetyl (hexadecyl) pyridineum chloride using mono and divalent oxyanions. JOURNAL OF HAZARDOUS MATERIALS 2008; 160:502-507. [PMID: 18417282 DOI: 10.1016/j.jhazmat.2008.03.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2007] [Revised: 11/27/2007] [Accepted: 03/07/2008] [Indexed: 05/26/2023]
Abstract
Experimental investigations have been carried out to observe the performance of precipitation behavior of potassium permanganate (KMnO4) and potassium dichromate (K2Cr2O7) in cetyl (hexadecyl) pyridineum chloride (CPC) solution. As in the case of Al3+-dodecylbenzenesulfonate systems [P. Somasundaran, K.P. Anathapadmanabhan, M.S. Celik, Langmuir 4 (1988) 1061-1063], the precipitation is found to be caused by interaction of CPC micelles with oxyanions. The counter oxyanions have a strong tendency to bind themselves to the surface of cationic CPC micelles. This lowered the free oxyanion concentration in solution. Therefore, to start precipitation, higher oxyanion concentration is required for higher CPC concentration. The effects of temperature, concentrations of both counter ions and CPC on the precipitation have been studied in detail. It has been observed that at CPC to KMnO4 concentration ratio of 1.0 (concentration of CPC and KMnO4 is 400ppm), the percentage precipitation of CPC is around 99.3 at 30 degrees C. The percent precipitation of CPC decreases to about 94% when temperature increases to 70 degrees C at the same condition. The extent of CPC precipitation increases at the same experimental condition when K2Cr2O7 is used instead of KMnO4.
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Dasgupta S, Gottschalk S, Kruk R, Hahn H. A nanoparticulate indium tin oxide field-effect transistor with solid electrolyte gating. NANOTECHNOLOGY 2008; 19:435203. [PMID: 21832686 DOI: 10.1088/0957-4484/19/43/435203] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Reversible tuning of the transport properties of metallic conducting systems is not reported widely in the literature. Here, we report a junction field-effect transistor (FET) based on a transparent conducting oxide (TCO) nanoparticle channel and a solid polymer electrolyte as a gate. The device principle is based on the variation of the drain current induced by the capacitive double layer charging at the electrolyte/nanoparticle interfaces. A device with a metallic conducting channel made of indium tin oxide (ITO) nanoparticles exhibits an on/off ratio of 2 × 10(3) even when the gate potential is limited within the electrochemical capacitive region to avoid redox reactions at the interface. An FET device with metal-like conductance is always favored for the low dimensions of the device and a high on-state current. The field-effect mobility is calculated to be 24.3 cm(2) V(-1) s(-1). A subthreshold swing between 230 and 425 mV dec(-1) is observed.
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Anderson JA, Jana M, Dasgupta S, Liu X, Pahan K. Involvement of P38MAP kinase in the induction of nitric oxide synthase in human astrocytes. J Neurochem 2008. [DOI: 10.1046/j.1471-4159.81.s1.18_3.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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