Dohutia C.,Regional Medical Research Center |
Bhattacharyya D.R.,Regional Medical Research Center |
Sharma S.K.,Regional Medical Research Center |
Mohapatra P.K.,Regional Medical Research Center |
And 6 more authors.
Tropical Biomedicine | Year: 2015
Mosquitoes are the vectors of several life threatening diseases like dengue, malaria, Japanese encephalitis and lymphatic filariasis, which are widely present in the north-eastern states of India. Investigations on five local plants of north-east India, selected on the basis of their use by indigenous communities as fish poison, were carried out to study their mosquito larvicidal potential against Anopheles stephensi (malaria vector), Stegomyia aegypti (dengue vector) and Culex quinquefasciatus (lymphatic filariasis vector) mosquitoes. Crude Petroleum ether extracts of the roots of three plants viz. Derris elliptica, Linostoma decandrum and Croton tiglium were found to have remarkable larvicidal activity; D. elliptica extract was the most effective and with LC50 value of 0.307 μg/ml its activity was superior to propoxur, the standard synthetic larvicide. Half-life of larvicidal activity of D. elliptica and L. decandrum extracts ranged from 2-4 days. © 2015, Malaysian Society for Parasitology. All rights reserved.
Prakash A.,Regional Medical Research Center |
Sharma S.K.,Regional Medical Research Center |
Mohapatra P.K.,Regional Medical Research Center |
Gogoi K.,Regional Medical Research Center |
And 3 more authors.
Parasitology Research | Year: 2013
Malaria control is compromised worldwide by continuously evolving drug-resistant strains of the parasite demanding exploration of natural resources for developing newer antimalarials. The northeastern region of India is endemic for malaria characterized by high prevalence of drug-resistant Plasmodium falciparum strains. Many plants are used by the indigenous communities living in the northeast India in their traditional system of medicine for the treatment of malarial fever. Folklore claim of antimalarial property of one such plant Brucea mollis was evaluated in vitro and in vivo for antiplasmodial activity. Crude extracts from dried B. mollis root powder were prepared through soxhlet extraction using petroleum ether, methanol, and water sequentially. Methanol extract was further partitioned between chloroform and water. These extracts were tested in vitro against laboratory-adapted chloroquine-sensitive and chloroquine-resistant strains of P. falciparum. In in vitro evaluation, extracts were found more active on the chloroquine-sensitive strain. Methanolic-chloroform (IC50 5.1 μg ml-1) and methanolic-aqueous (IC50 13.9 μg ml-1) extracts recorded significant in vitro antiplasmodial activity which was also supported by their promising in vivo activity (ED50 72 and 30 mg kg -1 bw day-1, respectively) against chloroquine-resistant Plasmodium yoelli N-67 strain in Swiss albino mice. Methanolic-aqueous extract-treated mice survived on average for 14 days that was comparable to the reference drug chloroquine. This is the first report of antiplasmodial activity of B. mollis validating the traditional use of this plant as antimalarial in the northeast India and calls for further detailed investigations. © 2012 Springer-Verlag Berlin Heidelberg.
Abir R.,Saha Institute of Nuclear Physics |
Jamil U.,Dr College |
Mustafa M.G.,Saha Institute of Nuclear Physics |
Srivastava D.K.,Variable Energy Cyclotron Center
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2012
We obtain the radiative energy loss of a heavy quark in a deconfined medium due to radiation of gluons off them using a recently derived generalised gluon emission spectrum. We find that the heavy flavour loses energy almost in a similar fashion like light quarks through this process. With this, we further analyse the nuclear modification factor for D-meson at LHC and RHIC energies. In particular, the obtained result is found to be in close agreement with the most recent data from ALICE collaboration at 2.76 ATeV Pb-Pb collisions. We also discuss the nuclear modification factor due to the collisional energy loss. Furthermore, the result of non-photonic single electron from the decay of both D- and B-mesons is compared with the RHIC data at 200 AGeV Au-Au collisions, which is also in close agreement. © 2012 Elsevier B.V.
Basumatary R.,Dr College |
Sharma D.K.,Gauhati University
Herpetology Notes | Year: 2013
We present morphometric and natural history observations on 14 species of freshwater turtles of Kaziranga National Park, India, documented in our study during 2008-2010. Turtle species assemblage in Brahmaputra river is found to be highest followed by Diffolu river and wetlands. Observations on microhabitat, reproductive behaviour has been included. Among so far recorded chelonians from the park, Nilssonia nigricans is extinct in the wild, whereas Chitra indica, Pangshura sylhetensis, Cuora mouhotii and Manouria emys are endangered. Though well protected inside the park, the turtles are threatened with habitat destruction and excessive fishing in certain areas.
Chutia P.,Dr College |
Solanki G.S.,Mizoram University
Tropical Ecology | Year: 2013
We conducted a questionnaire survey to document the patterns of bird hunting among the Nyishi, Apatani and Monpa tribes of Western Arunachal Pradesh, India. A total of 157 hunters representing 57% Nyishis, 20% Monpas and 23% Apatanis were interviewed to ascertain the seasonality of hunting and number of bird species hunted. Fifty three species of birds including 18 belonging to Schedule I of India's Wildlife (Protection) Act were hunted by the interviewees. Examples of Schedule I species hunted in the region are hornbills, eagles and owls. Passeriformes were hunted most (40%) followed by Ciconiformes (19%) and Strigiformes (9%). These families constituted 70% of the total species hunted. Hornbills and Galliformes are the most threatened groups in the region. Hunting is intensive during jhum cultivation and harvesting of the crops. However, hunting time and season vary with the species. The average rate of hunting from all major tribal groups is 6 birds hunter-1 year-1. The rate of loss from the study area is 10,956 birds year-1. The implications of the hunting on biodiversity are discussed. © International Society for Tropical Ecology.
Dutta S.,Tezpur University |
Dutta S.,Dr College |
Karak N.,Tezpur University |
Saikia J.P.,Tezpur University |
Konwar B.K.,Tezpur University
Journal of Polymers and the Environment | Year: 2010
Mesua ferrea L. seed oil (MFLSO) modified polyurethanes blends with epoxy and melamine formaldehyde (MF) resins have been studied for biodegradation with two techniques, namely microbial degradation (broth culture technique) and natural soil burial degradation. In the former technique, rate of increase in bacterial growth in polymer matrix was monitored for 12 days via a visible spectrophotometer at the wavelength of 600 nm using McFarland turbidity as the standard. The soil burial method was performed using three different soils under ambient conditions over a period of 6 months to correlate with natural degradation. Microorganism attack after the soil burial biodegradation of 180 days was realized by the measurement of loss of weight and mechanical properties. Biodegradation of the films was also evidenced by SEM, TGA and FTIR spectroscopic studies. The loss in intensity of the bands at ca. 1735 cm -1 and ca. 1050 cm -1 for ester linkages indicates biodegradation of the blends through degradation of ester group. Both microbial and soil burial studies showed polyurethane/epoxy blends to be more biodegradable than polyurethane/MF blends. Further almost one step degradation in TG analysis suggests degradation for both the blends to occur by breakage of ester links. The biodegradation of the blends were further confirmed by SEM analyses. The study reveals that the modified MFLSO based polyurethane blends deserve the potential to be applicable as "green binders" for polymer composite and surface coating applications. © 2010 Springer Science+Business Media, LLC.
Borah M.N.,Dr College |
Baruah B.J.,Dr College |
Chaliha S.,Bahona College |
Gogoi D.P.,Bahona College |
And 2 more authors.
Journal of Experimental Nanoscience | Year: 2013
Nanocrystalline CdSe films are deposited on glass substrates by the chemical bath deposition method at different molarities and at room temperature. The structural parameters such as lattice constant, internal strain and dislocation density of CdSe nanocrystals are measured from X-ray diffractrograms using the Williamson-Hall plot. The average crystallite size of prepared films are found to be from 9.5 to 26 nm. The prepared films are found to be under compressive strain with very high dislocation density of the order of 1017 line m-2. © 2013 Copyright Taylor and Francis Group, LLC.
PubMed | Regional Medical Research Center and Dr College
Type: Journal Article | Journal: Tropical biomedicine | Year: 2015
Mosquitoes are the vectors of several life threatening diseases like dengue, malaria, Japanese encephalitis and lymphatic filariasis, which are widely present in the north-eastern states of India. Investigations on five local plants of north-east India, selected on the basis of their use by indigenous communities as fish poison, were carried out to study their mosquito larvicidal potential against Anopheles stephensi (malaria vector), Stegomyia aegypti (dengue vector) and Culex quinquefasciatus (lymphatic filariasis vector) mosquitoes. Crude Petroleum ether extracts of the roots of three plants viz. Derris elliptica, Linostoma decandrum and Croton tiglium were found to have remarkable larvicidal activity; D. elliptica extract was the most effective and with LC50 value of 0.307 g/ml its activity was superior to propoxur, the standard synthetic larvicide. Half-life of larvicidal activity of D. elliptica and L. decandrum extracts ranged from 2-4 days.