Showing papers by "Jawaharlal Nehru University published in 1997"
TL;DR: The aim is to use Fourier techniques to analyse this periodicity, and thereby to develop a tool to recognize coding regions in genomic DNA, and find that the relative-height of the peak at f = 1/3 in the Fourier spectrum is a good discriminator of coding potential.
Abstract: Motivation: The major signal in coding regions of genomic sequences is a three-base periodicity. Our aim is to use Fourier techniques to analyse this periodicity, and thereby to develop a tool to recognize coding regions in genomic DNA. Result: The three-base periodicity in the nucleotide arrangement is evidenced as a sharp peak at frequency f — 1/3 in the Fourier (or power) spectrum. From extensive spectral analysis of DNA sequences of total length over 5.5 million base pairs from a wide variety or organisms (including the human genome), and by separately examining coding and non-coding sequences, we find that the relative height of the peak at f = 1/3 in the Fourier spectrum is a good discriminator of coding potential. This feature is utilized by us to detect probable coding regions in DNA sequences, by examining the local signal-to-noise ratio of the peak within a sliding window. While the overall accuracy is comparable to that of other techniques currently in use, the measure that is presently proposed is independent of training sets or existing database information, and can thus find general application. Availability: A computer program GeneScan which locates coding open reading frames and exonic regions in genomic sequences has been developed, and is available on request. Contact: E-mail: rama@jnuniv.emet.in.
469 citations
TL;DR: The role of endogeic species in intensifying agroecosystems is likely to be more important for soil function, especially because they act as ecosystem engineers and through their mutualistic interactions with microflora, selective ingestion of soil particles, high rates of ingestion and production of casts, galleries, burrows and chambers can affect nutrient and organic matter dynamics and other pedological processes.
233 citations
TL;DR: It is demonstrated that proline is involved in reducing the photodamage in the thylakoid membranes by scavenging and/or reducing the production of 1O2.
Abstract: Investigations were carried out to determine the involvement of proline in protecting thylakoid membranes against photodamage. The exposure of thylakoids isolated from the cotyledons of Brassica juncea to photoinhibitory light caused a linear increase in lipid peroxidation with time as measured by the assay of conjugated dienes and malondialdehyde (MDA). Proline produced a considerable reduction in the lipid peroxidation-linked formation of both conjugated dienes and MDA in the thylakoids during exposure to strong light. This reduction in lipid peroxidation reflects the probable involvement of proline in the reduction of the free radicals generated on strong light exposure. The thylakoids exposed to strong light intensity also generated singlet oxygen (1O2) and superoxide radical anion (O2−1). The level of these radicals increased with the time of exposure. The presence of proline significantly curtailed the production of 1O2 by the thylakoids during strong illumination. However, the presence of proline did not affect the O2− induction capacity of the thylakoid membranes during strong light exposure. Peroxidation of linolenic acid micelles occurred on exposure to UV radiation. The almost total suppression of UV-induced lipid peroxidation of linolenic acid micelles in the presence of sodium azide and L-histidine (singlet oxygen quenchers) suggested the involvement of 1O2 in UV-induced lipid peroxidation. The presence of proline during the exposure of linolenic acid micelles to UV radiation caused a considerable reduction in the formation of conjugated dienes as well as MDA. The proline-induced reduction in the peroxidation of these micelles further confirms the involvement of proline in reducing the level of 1O2. Our results therefore demonstrate that proline is involved in reducing the photodamage in the thylakoid membranes by scavenging and/or reducing the production of 1O2.
168 citations
TL;DR: The sediment load of the Ganges-Brahmaputra-Meghna (GBM) river system consists exclusively of fine sand, silt and clay at their lower reaches within the Bengal basin, Bangladesh, and is deposited under uniformly fluctuating, unidirectional energy conditions.
Abstract: The Bengal basin, Bangladesh, represents one of the most densely populated recent floodplains of the world. The sediment flux through the basin is one of the highest on a global scale. A significant portion of this sediment load find its sink in the basin itself because of its lower elevation and frequent flooding. The textural, mineralogical and chemical nature of the sediments thus have an important bearing on the environmental quality of the basin as well as for the Bay of Bengal. The sediment load of the Ganges-Brahmaputra-Meghna (GBM) river system consists exclusively of fine sand, silt and clay at their lower reaches within the Bengal basin, Bangladesh, and is deposited under uniformly fluctuating, unidirectional energy conditions. The sediments have a close simitarity in grain size with the sediments of the surrounding floodplain. The mineral assemblage is dominated by quartz and feldspars. Illite and kaolinite are the major clay minerals, and occur in almost equal proportion in bed sediments. The heavy mineral assemblage is dominated by unstable minerals which are mostly derived from high-rank metamorphic rocks. The characteristic smaller grain-size, i.e. having large surface-to-mass ratios, and the mineralogy of sediments suggests that they are susceptible to large chemical adsorptive reactions and thus could serve as a potential trap for contaminants. However, the sediments of the GBM river system in the Bengal basin, Bangladesh, shows lower concentration of Pb, Hg and As, and a marginally higher value for Cd as compared to that of standard shale. Considering population density and extensive agricultural practice in the basin, the sediments can in the long run become contaminated.
125 citations
TL;DR: In this paper, the largest nontrivial Lyapunov exponent is used as a good order parameter for the transition from chaos to SNA to periodic motion in quasiperiodically driven systems in the neighborhood of saddle-node bifurcation.
Abstract: Strange nonchaotic attractors (SNA) arise in quasiperiodically driven systems in the neighborhood of a saddle-node bifurcation whereby a strange attractor is replaced by a periodic (torus) attractor. This transition is accompanied by Type-I intermittency. The largest nontrivial Lyapunov exponent $\ensuremath{\Lambda}$ is a good order parameter for this route from chaos to SNA to periodic motion: the signature is distinctive and unlike that for other routes to SNA. In particular, $\ensuremath{\Lambda}$ changes sharply at the SNA to torus transition, as does the distribution of finite-time or $N$-step Lyapunov exponents, $P({\ensuremath{\Lambda}}_{N})$.
93 citations
TL;DR: In this article, the dynamics of phase separation of a critical or near-critical binary mixture in the presence of a surface with a preferential attraction for one of the components of the mixture is considered.
Abstract: We critically review the modelling and simulations of surface-directed spinodal decomposition, namely, the dynamics of phase separation of a critical or near-critical binary mixture in the presence of a surface with a preferential attraction for one of the components of the mixture.
91 citations
TL;DR: In this article, the results obtained by Vives in this connection are reconsidered in a homogeneous product market and it is shown that these results are sensitive to the market sharing rules which have the property of including the competitive equilibrium in the set of Bertrand equilibria.
88 citations
TL;DR: It is likely that methylglyoxal undergoes a redox cycle and generates the free radicals which in turn lower the antioxidant status in animals, and the increased levels of lipid peroxidation provide support for the involvement of free radical processes in the detrimental effects of methyl glyoxal.
87 citations
TL;DR: The third largest river of India, the Godavari River, has been sampled for Particulate Inorganic and OrganicCarbon (PIC, POC), Particulated Nitrogen (PN), andParticulate Amino Acids (PAA, including 2 hexosamines(HA)) during the dry season POM in the upper reaches is relatively freshand autochthonous, in the lower reaches it is degradedand inorganic suspended matter content is higher as mentioned in this paper.
Abstract: The Godavari River, the third largest river of India,has been sampled for Particulate Inorganic and OrganicCarbon (PIC, POC), Particulate Nitrogen (PN), andParticulate Amino Acids (PAA, including 2 hexosamines(HA)). During the dry season Particulate OrganicMatter (POM) in the upper reaches is relatively freshand autochthonous, in the lower reaches it is degradedand inorganic suspended matter content is higher here.In the wet season (wet monsoon) heavy rains cause abasin-wide flushing of humus from entire catchmentarea consequently POM in the river is mainly degradedand allochthonous. Annual transport of the GodavariRiver amounts to 2.81 × 10 6 ton POC, 0.29 × 10 6ton PN and 0.10 × 10 6 tonParticulate Amino Acid Nitrogen. These amounts rank theGodavari River to one of the most important organic carbontransporting rivers in the world.
75 citations
TL;DR: In this article, measurements of ozone (O 3 ) and oxides of nitrogen (NO x ) were carried out at six sites in Delhi during the winter months of 1993, and the results showed that ozone exhibited initial high levels during morning hours which subsequently declined to lower levels around noon.
74 citations
TL;DR: In this article, it was shown that gamma-aminobutyric acid (GABA) is involved in tonic regulation of rapid eye movement sleep and the action is mediated through GABAA receptor.
TL;DR: In this paper, the dielectric behavior of supercooled aqueous solutions of DMSO, EEG, and methanol has been examined in the frequency range 106−10-3 Hz and in the...
Abstract: The dielectric behavior of the supercooled aqueous solutions of dimethyl sulfoxide (DMSO), ethylene glycol (EG), and methanol (MeOH) has been examined in the frequency range 106−10-3 Hz and in the ...
TL;DR: In this article, the use of SNAs rather than chaotic attractors can offer some advantages in experiments involving synchronization with aperiodic dynamics, which can be used for applications such as secure communication.
Abstract: Strange nonchaotic attractors (SNAs), which are realized in many quasiperiodically driven nonlinear systems, are strange (geometrically fractal) but nonchaotic (the largest nontrivial Lyapunov exponent is negative). Two such identical independent systems can be synchronized by in-phase driving: Because of the negative Lyapunov exponent, the systems converge to a common dynamics, which, because of the strangeness of the underlying attractor, is aperiodic. This feature, which is robust to external noise, can be used for applications such as secure communication. A possible implementation is discussed and its performance is evaluated. The use of SNAs rather than chaotic attractors can offer some advantages in experiments involving synchronization with aperiodic dynamics.
TL;DR: In this article, the authors present extensive results from two-dimensional simulations of phase-separation kinetics in a model with order-parameter dependent mobility, and show that the time-dependent structure factor exhibits dynamical scaling and the scaling function is numerically indistinguishable from that for the Cahn-Hilliard (CH) equation, even in the limit where surface diffusion is the mechanism for domain growth.
Abstract: We present extensive results from two-dimensional simulations of phase-separation kinetics in a model with order-parameter dependent mobility. We find that the time-dependent structure factor exhibits dynamical scaling and the scaling function is numerically indistinguishable from that for the Cahn-Hilliard (CH) equation, even in the limit where surface diffusion is the mechanism for domain growth. This supports the view that the scaling form of the structure factor is ``universal'' and leads us to question the conventional wisdom that an accurate representation of the scaled structure factor for the CH equation can only be obtained from a theory which correctly models bulk diffusion.
TL;DR: In this paper, the average land holding was 0.84 ha split into two distant plots, one in the upland and the other in the valley, and a high level of crop diversity was maintained by rotation of crops in time and space on small fields.
Abstract: The State of Himachal Pradesh in the north-western Indian Himalaya is distinguished for integration of profit-oriented horticulture and use of modern yield-increasing inputs in the traditional, subsistence-economy-centered agriculture in the recent past. Farming systems in the two neighboring villages of the State were analysed. The average land holding was 0.84 ha split into two distant plots, one in the upland and the other in the valley. A high level of crop diversity (14 rainy season crops and 3 winter season crops) was maintained by rotation of crops in time and space on small fields, together with coexistence of mixed and monocropping practices. Upland, terraced agroecosystems were more diversified, as well as efficient in terms of energy and monetary rates of return, than the valley agroecosystems. Potatoes showed the highest energy and monetary output:input ratio. Mixed cropping was not as dominant as monocropping. Following the introduction of apples in the croplands, rates of return dec...
TL;DR: In this article, the authors present detailed numerical results for phase-separation kinetics of critical binary mixtures in the vicinity of a surface that exerts a long-ranged attractive force on one of the components of the mixture.
Abstract: We present detailed numerical results for phase-separation kinetics of critical binary mixtures in the vicinity of a surface that exerts a long-ranged attractive force on one of the components of the mixture. We consider surface potentials of the form $V(Z)\ensuremath{\sim}{Z}^{\ensuremath{-}n}$, where $Z$ is the distance from the surface and $n=1,2,3$. In particular, we investigate the interplay of the surface wetting layer with the dynamics of domain growth. We find that the wetting layer at the surface exhibits power-law growth with an exponent that depends on $n$, in contrast to the case with a short-ranged surface potential, where the growth is presumably logarithmic. From correlation functions, we identify characteristic length scales in directions parallel and perpendicular to the surface. We observe a regime of accelerated growth in the parallel direction and critically examine some possible explanations for this.
TL;DR: In this paper, a fully dynamical calculation of the orbital diamagnetism of a charged particle in a magnetic field is presented, from which the effect of dissipation on Landau diamagnetic properties can be assessed.
Abstract: Starting from a quantum Langevin equation of a charged particle in a magnetic field we present a fully dynamical calculation of the orbital diamagnetism, from which the effect of dissipation on Landau diamagnetism can be assessed. The treatment throws light on subtle issues of confined boundaries and the approach to equilibrium of a quantum dissipative system. Additional results are presented for the diamagnetism in a confined parabolic potential. {copyright} {ital 1997} {ital The American Physical Society}
TL;DR: In this article, the authors discuss the five decades of India's experience of migration of highly qualified personnel (HQP), as presented in this paper, broadly falls into three distinct but overlapping periods, namely: 1940s to 1960s, 1970 to 1980s, and 1990s and beyond.
Abstract: Five decades of India's experience of migration of highly qualified personnel (HQ P), as presented in this paper, broadly falls into three distinct but overlapping periods, namely: 1940s to 1960s; 1970 to 1980s; and 1990s and beyond. In the post-indepen dence period up to the 1960s, India did not really experience the trend of brain drain. The demand pattern created by the official policies to expand the university sector and strengthen the infrastructure in science and technology determined the human resource policies in training, higher education and even attracted some established Indian scientists from abroad during this early phase. Beginning with the 1970s, India began to experience the problem of brain drain, for which several economic and sociological factors were responsible including the oversupply of HQP and the lack of demand for these personnel. Even though different trends are discernible during the 1980s and 1990s, the case discussed here illustrates that India continues to lose its scienti...
TL;DR: It is successfully demonstrated that HIV1 Rev binds with labeled 34-kDa HABP which can be competed with excess unlabeled HABp, suggesting this protein can be a cellular factor promoting HIV1Rev to function.
TL;DR: Indirect immunofluorescence and immunoprecipitation analyses using specific antibodies against EhCaBP suggest that it is a soluble cytoplasmic protein with no major post-translational modification and there may be novel Ca(2+)-signal transduction pathway in E. histolytica mediated by EhCa BP.
TL;DR: The potential of arecoline alkaloid to modify the chemopreventive efficacy of phytic acid, via modulation of hepatic biotransformation system enzymes and antioxidant defence mechanism, was assessed in a murine system.
TL;DR: In this paper, the authors examined the child labour-based industry of match production in India, which is concentrated in the Sivakasi-Sattur matchbelt of Tamil Nadu, and argued that the abolition of child labour, while reducing the excessive trading margins and changing the irrational locational structure characterising this industry, would in fact result in higher earnings for adult workers.
Abstract: The abolition of child labour in underdeveloped countries is often held to be practically infeasible because it would entail closure of the economic activities which exist only because of access to such labour. Abolition, therefore, would reduce the earnings of poor households whose survival strategies, in the context of adult unemployment, depend on incomes derived from the practice. This article examines the child labour‐based industry of match production in India, which is concentrated in the Sivakasi‐Sattur matchbelt of Tamil Nadu. It is argued that the abolition of child labour, while reducing the excessive trading margins and changing the irrational locational structure characterising this industry, would in fact result in higher earnings for adult workers. However, it could have adverse consequences for a section of workers, which can be addressed with appropriate state action.
TL;DR: In this paper, it is shown that limited liability and moral hazard in effort provides a richer theory of share contracts when the tenant also has discretion in the choice of projects. But the authors do not consider the problem of share tenancy in the context of share-tenancy.
TL;DR: Data show that, while in water substance P appears to favour an extended chain conformation, in the presence of perdeuterated dodecylphosphocholine micelles as membrane model system an amphiphilic helical conformation is induced in the mid-region of substance P.
Abstract: Both the aqueous and the lipid-induced structure of a representative and widely studied tachykinin, substance P, has been investigated by two-dimensional proton nuclear magnetic resonance (2D 1H-NMR) spectroscopy and distance geometry calculations. Unambiguous NMR assignments of protons have been made with the aid of correlation spectroscopy (COSY and TOCSY) experiments and Overhauser enhancement spectroscopy (ROESY and NOESY; experiments. The NMR data obtained were utilized in a distance geometry algorithm to generate a family of structures which were further refined using restrained energy minimization. These data show that, while in water substance P appears to favour an extended chain conformation, in the presence of perdeuterated dodecylphosphocholine (DPC) micelles as membrane model system an amphiphilic helical conformation is induced in the mid-region (Q5-Q8) of substance P. The conformation adopted by substance P in the presence of DPC micelles yields a structural motif typical of neurokinin-1 selective ligands, as proposed by Convert and coworkers (O. Convert et al., Neuropeptides 19, 259-270 (1991)).
TL;DR: The armies of India and the dynamics of imperial rule, the structure and ideologies of company rule ideologies of the garrison state, the military resources of the army and the finances of British India, in action -the Burma War and the campaign against Bharatpur economies, imperial authority and war Anglo-Indian militarism in an age of retrenchment and reform conclusion -the survival of the British garrison state as mentioned in this paper.
Abstract: The armies of India and the dynamics of imperial rule the structure and ideologies of company rule ideologies of the garrison state the military resources of the garrison state the army and the finances of British India the garrison state in action - the Burma War and the campaign against Bharatpur economies, imperial authority and war Anglo-Indian militarism in an age of retrenchment and reform conclusion - the survival of the garrison state.
TL;DR: In this article, traditional knowledge, uses, monetary costs, and benefits associated with medicinal plants were analyzed in the Chhakinal watershed of Northwestern Himalaya, and the medicinal value of four species, Dioscorea deltoidea, Podophyllum hexandrum, Valeriana jatamansi, and Jurinea macrocephala, were unknown to local people, but sold for cash income.
Abstract: Traditional knowledge, uses, monetary costs, and benefits associated with medicinal plants were analyzed in the Chhakinal watershed of Northwestern Himalaya. Of 29 plant species used in folk medicine, only 3 species, Juglans regia, Picrorrhiza kurrooa, and Morchella esculenta were noted to have market value. The medicinal value of four species, Dioscorea deltoidea, Podophyllum hexandrum, Valeriana jatamansi, and Jurinea macrocephala, were unknown to local people, but sold for cash income. Use of medicinal plants in the traditional health care system of the area varied, depending upon the species and ailment. A total of 11 species were used for disorders related to digestive system, six species were used for skin infections, and three species were used for joint or muscular pain. The medicinal plants grew in government owned forests and other uncultivated lands as constituents of natural vegetation. Alpine vegetation had the greatest number of medicinal plant species, while forests had the greates...
TL;DR: The results suggest that, contrary to the action of adrenergic inputs, the cholinergic input is unlikely to have a dissociated effect on sleep-wakefulness and body temperature and this regulation is mediated through muscarinic receptors present in this area.
TL;DR: In this article, the authors investigated the complexation interactions of copper, cadmium and lead, in their divalent states, with humic acids extracted from three different sources: the treated sewage from a treatment plant, Yamuna river bed sediment, and Yamuna River flood plain soil, all at Okhla, Delhi.
Abstract: Metal—humate interactions in aqueous and terrestrial ecosystems control the speciation of trace metals and hence, their bioavailability and toxicity. The present study investigated the complexation interactions of copper, cadmium and lead, in their divalent states, with humic acids extracted from three different sources: the treated sewage from a treatment plant, Yamuna river bed sediment, and Yamuna river flood plain soil, all at Okhla, Delhi, employing ion selective electrode potentiometry. The conditional stability constants of the complexes were computed from Scatchard plots. The influences of the two important metal speciation factors, viz., pH and ionic strength of the reaction medium on the conditional stability constants were ascertained by investigating the reactions under three different pH: 5.0, 6.0 and 7.0 and three different ionic strengths: 0.01, 0.03 and 0.1. Stabilities of metal—humic acid (HA) complexes follow the order: Cu-HA > Pb-HA > Cd-HA for humic acids from any single source...
TL;DR: Results demonstrate that, in addition to the cofactor, the N-terminal arm plays an important role in stabilizing the tetrameric structure of SHMT.
Abstract: The role of the amino and carboxyl-terminal regions of cytosolic serine hydroxymethyltransferase (SHMT) in subunit assembly and catalysis was studied using six amino-terminal (lacking the first 6, 14, 30, 49, 58, and 75 residues) and two carboxyl-terminal (lacking the last 49 and 185 residues) deletion mutants. These mutants were constructed from a full length cDNA clone using restriction enzyme/PCR-based methods and overexpressed in Escherichia coli. The overexpressed proteins, des-(A1-K6)-SHMT and des-(A1- W14)-SHMT were present in the soluble fraction and they were purified to homogeneity. The deletion clones, for des-(A1–V30)-SHMT and des-(A1–L49)-SHMT were expressed at very low levels, whereas des-(A1–R58)-SHMT, des-(A1–G75)-SHMT, des-(Q435–F483)-SHMT and des-(L299-F483)-SHMT mutant proteins were not soluble and formed inclusion bodies. Des-(A1–K6)-SHMT and des-(A1–W14)-SHMT catalyzed both the tetrahydrofolate-dependent and tetrahydrofolate-independent reactions, generating characteristic spectral intermediates with glycine and tetrahydrofolate. The two mutants had similar kinetic parameters to that of the recombinant SHMT (rSHMT). However, at 55 °C, the des-(A1–W14)-SHMT lost almost all the activity within 5 min, while at the same temperature rSHMT and des-(A1–K6)-SHMT retained 85% and 70% activity, respectively. Thermal denaturation studies showed that des-(A1–W14)-SHMT had a lower apparent melting temperature (52°C) compared to rSHMT (56°C) and des-(A1–K6)-SHMT (55 °C), suggesting that N-terminal deletion had resulted in a decrease in the thermal stability of the enzyme. Further, urea induced inactivation of the enzymes revealed that 50% inactivation occurred at a lower urea concentration (1.2 ± 0.1 M) in the case of des-(A1–W14)-SHMT compared to rSHMT (1.8 ±0.1 M) and des-(A1–K6)-SHMT (1.7 ±0.1 M). The apoenzyme of des-(A1- W14)-SHMT was present predominantly in the dimer form, whereas the apoenzymes of rSHMT and des-(A1–K6)-SHMT were a mixture of tetramers (≈75% and ≈65%, respectively) and dimers. While, rSHMT and des-(A1–K6)-SHMT apoenzymes could be reconstituted upon the addition of pyridoxal-5′-phosphate to 96% and 94% enzyme activity, respectively, des-(A1–W14)-SHMT apoenzyme could be reconstituted only upto 22%. The percentage activity regained correlated with the appearance of visible CD at 425 nm and with the amount of enzyme present in the tetrameric form upon reconstitution as monitored by gel filtration. These results demonstrate that, in addition to the cofactor, the N-terminal arm plays an important role in stabilizing the tetrameric structure of SHMT.
TL;DR: The data presented here indicate a role for the 34-kDa hyaluronan binding protein in cellular signal transduction and the regulation of the cellular and cell surface phosphorylation of HA-binding protein by HA, PMA and calyculin-A was demonstrated in different cell lines.