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Wyszukujesz frazę "Das, S K." wg kryterium: Autor


Tytuł:
A Green Function Estimation of Correction to Vegards Law for isovalent Substitutional Defects in Alkali Halide Crystals
Autorzy:
Datta Roy (Paul), S.
Das, S. K.
Powiązania:
https://bibliotekanauki.pl/articles/2013286.pdf
Data publikacji:
2000-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.72.Bb
61.82.Bg
Opis:
A Green function method is developed for estimation of lattice parameter r(χ) of an AX-BX solid solution over entire composition range (χ=0 to 1). The r(χ) obtained in the present method is different from the value r$\text{}_{V}$(χ) suggested by Vegard's law. We estimated the deviation from Vegard's law, r(χ)-r$\text{}_{V}$(χ), over entire composition range for isovalent substitutional defect in alkali halide crystals. When compared to X-ray diffraction measurements, we find that the deviation is in correct direction, variation of r(χ) with χ is consistent with experiment and the overall agreement is fairly good considering the accuracy of the experiment.
Źródło:
Acta Physica Polonica A; 2000, 97, 4; 671-679
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A study on the occurrence of Asian open bill stork, Anastomus oscitans in particular tree species at Nature Park, Kolkata, India
Autorzy:
Das, A.
Sarkar, S.
Banerjee, K.
Nandy, A.
Talapatra, S.N.
Swarnakar, S.
Powiązania:
https://bibliotekanauki.pl/articles/11152.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Opis:
The trees support many bird and animal species while the survival of urban-dwelling species e.g. bird species dominate over others. This particular Nature park in Kolkata is the habitat of birds and fish species suggesting a better environment for food chain maintenance. The Asian open bill stork, Anastomus oscitans among other bird species is a common and provides ecosystem health indicator. The present study aims to understand the occurrence and population nos. of Asian open bill stork on particular tree species surrounding wetlands at Nature Park, Kolkata, India. Our results clearly indicate that a total population of this bird species having 671 nos. on the particular trees but not in all other available trees in the study area. In conclusion, present research emphasizes a novel occurrence and higher population of the A. oscitans being observed on the basis of the presence of particular tree species, though no attempt has been made on physico-chemical properties of present water and microclimate within the park. Therefore, further research planning should be oriented considering the physico-chemical impacts as well as local microenvironment along with human interaction as visitors in such a way so that these barriers cannot affect nesting and breeding of those species as eco-indicator. Also further relevant research is needed to emphasize on the conservation of these specific tree species to increase population of Asian open bill stork, A. oscitans in Nature park.
Źródło:
International Letters of Natural Sciences; 2014, 22
2300-9675
Pojawia się w:
International Letters of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment of antimutagenic avenue and wild plant diversity on roadside near Nature Park, Kolkata, India
Autorzy:
Das, S.
Benerjee, K.
Nandy, A.
Nath Talapatra, S.
Powiązania:
https://bibliotekanauki.pl/articles/11170.pdf
Data publikacji:
2015
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Opis:
The study of diversity of plants in an urban area is a suitable measure of the terrestrial ecosystem. The study of avenue and wild plants diversity is an important research work, which provides knowledge about naturally occurring chemicals in plants, to protect against mutation, cancer and other diseases. These are commonly called as phytochemicals and the natural chemical ingredients are potent to use in antimutagenicity. The present study aims to understand the occurrence and population nos. of different avenue and wild plants planted or natural on roadside near Nature Park, Kolkata, India. The results clearly indicate that a total population of these plant species are having 282 nos. in the study area. Various literatures clearly revealed that these plants and/or their parts have potent antimutagenic properties by the presence of several phytochemicals. In conclusion, present preliminary research emphasizes an occurrence of antimutagenic avenue and wild plants on roadsides, containing natural chemical ingredients. Previous research works confirmed that toxins or mutagens or carcinogens may cause mutation that leads to cancer. The present study is a preliminary assessment of antimutagenic avenue and wild plant species diversity that have not yet been studied in that particular geographical area. The present study also suggested that avenue and wild plants are suitable for antimutagenic potential along with aesthetical view of human as well as ecosystem support. Therefore, biodiversity study, phytochemicals estimation and conservation of these particular plant species and/or different antimutagenic species in other local area viz. roadsides, parks, forests etc. might be relevant because the plant species can be used for herbal medicine in human healthcare as well as to prevent mutation and cancer.
Źródło:
International Letters of Natural Sciences; 2015, 02
2300-9675
Pojawia się w:
International Letters of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Biomonitoring tool: morphological anomalies in Zygnema sp. of Ganga River Bank
Autorzy:
Das, K.
Gupta, K.
Swarnakar, S.
Talapatra, S.N.
Powiązania:
https://bibliotekanauki.pl/articles/11639.pdf
Data publikacji:
2015
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Opis:
The present study aims to detect morphological abnormalities in Zygnema sp. because this test species have high adaptive capacity in unfavourable environmental stress. This alga is inhabited at the suburban bank of river Ganga, West Bengal, India. The study was done at experimental sites, downstream at Khardah near sewage water mixing area was compared with upstream control site Kalyani as no sewage water discharge. External and internal abnormal morphology such as undulating or wavy and extra outgrowth on cell wall, sometimes bending inwardly and outwardly as external deformities while internal anomalies such as pigment loss, nucleus was in circular, rectangular, oval and amoeboid shapes, also vacuolated and trilobed, broom like chloroplasts and central part of the thallas dried in between two segments. It was observed that this test species was surviving and well adapted with above mentioned deformities. The present preliminary study with Zygnema sp. can be utilized for in situ and ex situ indicator species for riverine biomonitoring. Further research may be relevant to know both tolerant and sensitive algae species inhabited at the river Ganga bank alongwith biochemical and genetic parameters. The present work is suggesting that other inhabiting algae and this adaptive test species can be used for bioremediation of pollutants.
Źródło:
International Letters of Natural Sciences; 2015, 47
2300-9675
Pojawia się w:
International Letters of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Breeding and agronomic approaches for the biofortification of zinc in wheat (Triticum aestivum L.) to combat zinc deficiency in millions of a population: a Bangladesh perspective
Biofortyfikacja pszenicy (Triticum aestivum L.) cynkiem w celu ograniczenia niedoboru cynku w populacji: perspektywa Bangladeszu
Autorzy:
Das, S.
Chaki, A.K.
Hossain, A.
Powiązania:
https://bibliotekanauki.pl/articles/27742.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Botaniczne
Opis:
The World Health Organization (WHO) has estimated that around 2 billion people across the globe are suffering from “hidden hunger”, where 815 million are under malnutrition. The major essential elements for humans are Fe, Zn, I, Se, Ca, F, and also vitamins. Among them, Zn is considered in the fifth place leading to causes of several deficiency diseases. At least one-third of the population in the world is facing Zn deficiency including around 450,000 children under the age of five. Vitamin A, Fe, and Zn deficiencies can be overcome through the biofortification of staple foodstuffs. This review emphasizes various breeding and agronomic approaches for the biofortification of Zn in wheat grains, which is an encouraging and cost-effective method to enhance the Zn contents of cereal grains. Recently, the Bangladesh Wheat and Maize Research Institute (BWMRI), with technical support from CIMMYT, Mexico, released a promising new Zn-biofortified wheat cultivar, ‘BARI Gom 33’, a result from a conventional breeding program. It has 32 and 50–55 mg kg−1 Zn without and with soil application of ZnSO4, respectively. This cultivar could be a savior for a million people in South Asia, including Bangladesh.
WHO (Światowa Organizacja Zdrowia) oceniła, że około 2 miliardy ludzi na całym świecie cierpi z powodu „ukrytego głodu”, podczas gdy 815 milionów cierpi z powodu niedożywienia. Głównymi pierwiastkami niezbędnymi w diecie dla człowieka są Fe, Zn, J, Se, Ca, F oraz witaminy. Cynk zajmuje 5 miejsce pod względem deficytu w pożywieniu, a jego niedobory prowadzą do wielu groźnych chorób. Co najmniej jedna trzecia populacji na świecie wykazuje objawy niedoboru Zn, w tym około 450000 dzieci poniżej piątego roku życia. Niedobory witaminy A, Fe i Zn można niwelować poprzez biofortyfikację podstawowych artykułów spożywczych. Niniejsza praca przeglądowa podkreśla różne podejścia hodowlane i agronomiczne do biofortyfikacji Zn w ziarniakach pszenicy, co może stanowić zachęcające i opłacalne narzędzie służące zwiększaniu zawartości Zn. Niedawno Bangladeski Instytut Badań Pszenicy i Kukurydzy (BWMRI), przy wsparciu technicznym Międzynarodowego Centrum Ulepszania Kukurydzy i Pszenicy (CIM-MYT) w Meksyku, przekazał nową, wzbogaconą w Zn odmianę biofortyfikowanej pszenicy ‘BARI Gom 33’ uzyskaną w ramach konwencjonalnego programu hodowlanego. Zawartość Zn w ziarniakach wynosi odpowiednio 32,09 i 50–55 μg L−1 Zn bez nawożenia i po doglebowym nawożeniu ZnSO4. Ta odmiana może uratować przed niedożywieniem milion ludzi w Azji Południowej, w tym w Bangladeszu.
Źródło:
Acta Agrobotanica; 2019, 72, 2
0065-0951
2300-357X
Pojawia się w:
Acta Agrobotanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Calculation of Lattice Relaxation in Some Substitutional Alloys Using a Green Function
Autorzy:
Das, S. K.
Datta Roy (Paul), S.
Powiązania:
https://bibliotekanauki.pl/articles/1995663.pdf
Data publikacji:
1999-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.72.Bb
61.82.Bg
Opis:
In this paper we calculate nearest neighbour relaxation in some dilute substitutional alloys using a lattice static Green function and the Morse potential function. Distant neighbour relaxation is calculated by invoking a continuum approximation. The potential parameters for the unlike interactions are calculated using simple interpolation formulae. Using the above relaxation, we calculate volume changes in the above alloys. It is observed that the simple model predicts values which are in reasonably good agreement with the experimental values in all cases. The calculated values are also compared with those obtained from the Vegard law. For Au-Ag alloy, our model reproduces both the correct sign and the magnitude of the volume change, whereas the Vegard law cannot even give the sign of the volume change. This shows the inherent strength of the present model.
Źródło:
Acta Physica Polonica A; 1999, 95, 3; 359-366
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development of Electrically Conductive Nanocrystalline Thin Film for Optoelectronic Applications
Autorzy:
Das, S K.
Islam, J. M. M.
Hasan, M.
Kabir, H.
Gafur, Md. A.
Hoque, E.
Khan, M. A.
Powiązania:
https://bibliotekanauki.pl/articles/412543.pdf
Data publikacji:
2013
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Conductive thin film
Composite
TiO2
Solar cell
Optoelectronics
Sodium alginate
Opis:
Sodium alginate (TiO2) sand composites were prepared by solution casting. Purified sand was added in the composite films to increase electrical conductivity. Electrical properties such as conductivity, capacitance, dielectric constant, and loss tangent of the composites were investigated. The current voltage characteristics for all the composites showed ohmic behavior. All the electrical properties have been found to improve with the incorporation of sand (SiO2) but 6 % sand containing composite exhibits the best electrical properties. The mechanical properties tensile strength (TS), elongation at break (Eb) and Young modulus for 6 % sand containing composite film are found to be 4.445 MPa, 9.76 %, and 72.8 MPa respectively. The experimental results reveal that the blended films exhibit higher stability and improved mechanical properties of both tensile strength and elongation at break in dry state. Water absorption properties of the composites are found to decrease with the increase of sand content. Lowest water uptake properties and highest stability were demonstrated by 6 % sand containing sample. Electrically conductive composite films have useful applications for solar cells and optoelectronics. Thus, this study is very much expected to aid in the design and selection of proper composite for the potential application of solar cell and optoelectronics.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2013, 10, 1; 90-101
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of organic inputs on strength and stability of soil aggregates under rice-wheat rotation
Autorzy:
Das, B.
Chakraborty, D.
Singh, V.K.
Aggarwal, P.
Singh, R.
Dwivedi, B.S.
Powiązania:
https://bibliotekanauki.pl/articles/25472.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
tensile strength
stability
soil aggregate
rice
wheat
cereal crop rotation
Opis:
The study aims to elucidate the impact of organic inputs on strength and structural stability of aggregates in a sandy loam soil. Tensile strength, friability and water stability of aggregates, and the carbon contents in bulk soil and in large macro (>2 mm), small macro (0.25-2 mm), micro (0.053-0.25 mm) and silt+clay size (<0.053) aggregates were evaluated in soils from a long-term experiment with rice-wheat rotation at Modipuram, India, with different sources and amounts of organic C inputs as partial substitution of N fertilizer. Addition of organic substrates significantly improved soil organic C contents, but the type and source of inputs had different impacts. Tensile strength of aggregates decreased and friability increased through organic inputs, with a maximum effect under green gram residue (rice)-farmyard manure (wheat) substitution. Higher macroaggregates in the crop residue- and farmyard manure-treated soils resulted in a higher aggregate mean weight diameter, which also had higher soil organic C contents. The bulk soil organic C had a strong relation with the mean weight diameter of aggregates, but the soil organic C content in all aggregate fractions was not necessarily effective for aggregate stability. The soil organic C content in large macroaggregates (2-8 mm) had a significant positive effect on aggregate stability, although a reverse effect was observed for aggregates <0.25 mm. Partial substitution of nitrogen by organic substrates improved aggregate properties and the soil organic C content in bulk soil and aggregate fractions, although the relative effect varied with the source and amount of the organic inputs.
Źródło:
International Agrophysics; 2014, 28, 2
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Estimation of Optimum Value of Y-Capacitor for Reducing Emi in Switch Mode Power Supplies
Autorzy:
Jha, M. M.
Naik, K. B.
Das, S. P.
Powiązania:
https://bibliotekanauki.pl/articles/262807.pdf
Data publikacji:
2009
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie
Tematy:
EMI
CM noise
touch current
Y-capacitor
Opis:
Putting a Y-capacitor between the primary ground and secondary ground is a common practice in industry to reduce EMI; but, this capacitor increases touch current. A method is discussed to measure the touch current at circuit design level. An optimum value of Y-capacitor is predicted without exceeding touch current limit. Experimental results of touch current measurements and EMI measurements are analyzed.
Źródło:
Electrical Power Quality and Utilisation. Journal; 2009, 15, 2; 47-50
1896-4672
Pojawia się w:
Electrical Power Quality and Utilisation. Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of antiepileptic activity of methanolic leaves extract of Tragia involucrata Linn. in mice
Autorzy:
Varma, G.G.
Mathai, B.K.
Das, K.
Gowda, G.
Rammohan, S.
Einstein, J.W.
Powiązania:
https://bibliotekanauki.pl/articles/11927.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
antiepileptic drug
antiepileptic activity
methanolic extract
leaf
plant extract
Tragia involucrata
Indian stinging nettle
mice
mouse
anticonvulsant action
pentylenetetrazol
picrotoxin
Opis:
The present investigation was aimed to study an antiepileptic activity of methanolic extract of Tragia involucrata Linn in mice. In vivo screening models like maximal electroshock-induced convulsion (MES), pentylenetetrazole (PTZ) and picrotoxin (PTX) induced models are used to evaluate the antiepileptic effects of the extracts. The biochemical estimation was done by measuring the lipid peroxidation and reduced glutathione (GSH). In the MES induced convulsion, methanolic extract of Tragia involucrata (METI) at high dose (800 mg/kg body weight), showed high significant inhibition on tonic hind limb extension (THLE, 6.83 ±0.30***) and decrease in duration of stupor period (108.7 ±6.53***). In PTZ and PTX induced model METI (400 mg/kg and 800 mg/kg) showed significant delay on the onset of convulsions, decreased duration of convulsion and reduced mortality significantly. It also showed significant decrease in brain MDA level in lipid peroxidation profile, and increase in the brain glutathione levels in mice against PTZ induced convulsion. The results confirmed that Tragia involucrata Linn possesses dose dependent antiepileptic activity.
Źródło:
International Letters of Natural Sciences; 2014, 12, 2
2300-9675
Pojawia się w:
International Letters of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
First report of twig blight of ban tulsi (Croton bonplandianus Bail.) caused by Choanephora cucurbitarum (Berk.and Ravenel) Thaxt. in India
Autorzy:
Das, S.
Dutta, S.
Ray, S.K.
Powiązania:
https://bibliotekanauki.pl/articles/65731.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
twig blight
ban tulsi
Croton bonplandianus
Euphorbiaceae
herb
perennial plant
folk medicine
Choanephora cucurbitarum
plant pathogen
sporangium
India
Opis:
In August 2015, twig blight disease of ban tulsi (Croton bonplandianus Bail.) caused by Choanephora cucurbitarum (Berk. & Ravenel) Thaxt. was observed for the first time, in the Gangetic alluvial region of West Bengal, India. A severe disease incidence (40–50%) showed twig blight symptoms starting with shoot apical meristem (SAM), leaf, and blossom blight symptoms. Typical symptoms were characterized by over-projecting black pin head like emerging sporangiola which formed mycelial cushion on the infected surface. The present report describes the identification of the causal pathogen as C. cucurbitarum based on its morphology and the internal transcribed spacer of its ribosomal DNA (rDNA – ITS) sequences with 100% identity of NCBI-GenBank published Choanephora database. Optimum temperatures, 28–30°C, coupled with high relative humidity (80–90%) during the monsoon season enhances the disease’s progress. To the best of our knowledge this is the first report of twig blight of C. bonplandianus, caused by C. cucurbitarum, in India as well as globally.
Źródło:
Journal of Plant Protection Research; 2017, 57, 4
1427-4345
Pojawia się w:
Journal of Plant Protection Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Flame Retardant and Antimicrobial Jute Textile Using Sodium Metasilicate Nonahydrate
Autorzy:
Basak, S.
Samanta, K. K.
Chattopadhyay, S. K.
Das, S.
Narkar, R.
Dsouza, C.
Shaikh, A. H.
Powiązania:
https://bibliotekanauki.pl/articles/779514.pdf
Data publikacji:
2014
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
flame retardant
sodium metasilicate nonahydrate
jute
LOI
antimicrobial
Opis:
Flame retardant and antimicrobial functionalities were imparted in jute textile using sodium metasilicate nonahydrate (SMSN), commonly known as “water glass”. Sodium metasilicate nonahydrate (SMSN) was applied in jute fabric in different concentration by padding method followed by drying. Flame retardancy of the fabric was evaluated by Limiting Oxygen Index (LOI) and burning behaviour under vertical flammability tester including the char length. Burning rate was found to decrease by almost 10 times after an application of 2% SMSN compared to the control sample. Thermogravimetry (TG) and differential scanning calorimetry (DSC) analysis of both the control and treated jute fabrics were utilized to understand the mechanism of developed flame retardance in jute fabric. It was observed that the SMSN treated samples showed excellent antimicrobial property against both gram positive and gram negative bacteria. Antimicrobial properties of both the control and treated jute fabrics were also measured quantitatively.
Źródło:
Polish Journal of Chemical Technology; 2014, 16, 2; 106-113
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Heuristic Procedure for the Assembly Line Balancing Problem With Postural Load Smoothness
Autorzy:
Jaturanonda, C.
Nanthavanij, S.
Das, S. K.
Powiązania:
https://bibliotekanauki.pl/articles/90459.pdf
Data publikacji:
2013
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
assembly line balancing
postural load smoothness
upper extremities disorders
RULA
linia montażowa
obciążenie
kończyny górne
Opis:
This paper presents a heuristic procedure for assigning assembly tasks to workstations where both productivity and ergonomics issues are considered concurrently. The procedure uses Kilbridge and Wester’s algorithm to obtain an initial task–workstation assignment solution which minimizes the balance delay of an assembly line. A task reassignment algorithm was applied to improve the initial solution by exchanging assembly tasks, which smooth postural load among workers, between workstations. A composite index of variation was used to measure the effectiveness of the task–workstation assignment solution. On the basis of clothes assembling, it was found that the task–workstation assignment solution with a minimum composite index of variation can be obtained with relatively equal weights in balance delay and postural load.
Źródło:
International Journal of Occupational Safety and Ergonomics; 2013, 19, 4; 531-541
1080-3548
Pojawia się w:
International Journal of Occupational Safety and Ergonomics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Identifying overlapping phylogenetic and geographic roots of HIV - 1 evolution through computational analyses
Autorzy:
Singh, P.K.
Banik, R.
Chakraborty, H.J.
Das, S.G.
Ganguli, S.
Datta, A.
Powiązania:
https://bibliotekanauki.pl/articles/11359.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
phylogenetic root
geographic root
evolution
computational analysis
HIV-1
genome
recombinant strain
AIDS
human disease
acquired immunodeficiency syndrome zob.AIDS
acquired immune deficiency syndrome zob.AIDS
Opis:
HIV-1 or Human Immuno Deficiency Virus-1 is the main causative agent of Acquired Immuno Deficiency Syndrome (AIDS). Human host infected with HIV - 1 extensively harbours many viral variants but very little is known about the difference in pattern[17] of evolution of phylogenetic lineages of HIV-1 non recombinant, normal inter subtype recombinant and main two specific recombinant forms of HIV-1 i.e., Circulating Recombinant Forms (CRFs) and Unique Recombinant Forms (URFs). This study is mainly concerned with study of the difference in evolutionary lineages of non-recombinant and recombinant sequences of HIV-1 genome sequences and identification of geographically rich areas which has reported high degree of HIV-1 occurrence and variety. Total 1550 HIV-1 genome sequences were obtained from HIV Los Alamos Database. The sequences were aligned using MAFFT (Multiple Alignment using Fast Fourier Transform) web server tool. Alignment was carried out using 10 different set of alignment parameter values. After alignment the aligned file was used for constructing N-J phylogenetic tree using Clustal X2 tool. Phylogenetic analysis was performed keeping in mind the category to which the sequence belongs. Upon analysis it was observed that the clade containing the probable ancestor belongs remained constant in all cases of different alignment values. Non recombinant isolates, inter subtype recombinants, CRFs, URFs all followed different patterns of evolution. Non recombinant sequences were found geographically specific and subtype specific to some extent whereas, normal recombinants were subtype specific and less geographically specific. CRFs showed variation among the pattern of their evolution. At some instances the sequences occurred as sister taxa of non-recombinant or normal inter subtype recombinant sequences, while at some instances as sister taxa of other CRFs where they were geographically specific. Three CRFs existed as completely diverged sequences. URFs were four in number; two of them were Indian isolates of while other two were Japanese isolates. URFs were found to be totally geographically specific. Geography wise high rate of variation was observed in India and Japan as these two countries had sequences belonging to all of the above categories. Cameroon and South Africa have very large number isolates and a considerable amount of genetic variation among isolates but they lack URFs.
Źródło:
International Letters of Natural Sciences; 2014, 02
2300-9675
Pojawia się w:
International Letters of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Kinetics and mechanism of electron transfer to pyridinium chlorochromate (VI) from sulfur containing amino acid, L-cysteine in aqueous and micellar media
Autorzy:
Senapati, S.
Das, S.
Mohanty, P.
Patnaik, A.K.
Powiązania:
https://bibliotekanauki.pl/articles/779166.pdf
Data publikacji:
2011
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
kinetyka
przeniesienie elektronu
chlorochromian pirydyny
cysteina
kinetics mechanism
electron transfer
pyridinium chlorochromate
cysteine
micellar media
Opis:
The electron transfer reaction of L-cysteine (RSH) with pyridinium chlorochromate (PCC) has been studied spectrophotometrically over the range 2.0 ≤ 10^3 [RSH] ≤ 6.0; 0.01 ≤ [H+] ≤ 0.2; 298 ≤ T ≤ 318 K and I = 0.3 mol dm-3 (NaClO4). The electron transfer reaction has also been carried out in the presence of anionic, cationic and neutral micelle. The reaction in acid medium is strongly catalyzed by changing [SDS]T (sodium dodecyl sulfate) up to 3 × 10-2 mol dm-3, beyond this concentration of SDS, the rate is retarded. The cationic and neutral micelle has a small effect on the rate. ΔH≠ (kJ mol-1) and ΔS≠ (JK-1 mol-1) values for the k1 and k2 paths are 30.20 ± 0.25, -159.65 ± 0.83 and 29.60 ± 0.62, -127.09 ± 2.17, respectively. The negative activation entropy is indicative of the ordered transition state for the electron transfer reaction. Formation of 2-amino-3-(2-amino-2-carboxy-ethyl) disulfanyl-propanoic acid as product is strongly supported by IR spectra.
Źródło:
Polish Journal of Chemical Technology; 2011, 13, 2; 6-10
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł

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