Showing papers by "North Eastern Hill University published in 2005"
TL;DR: In this paper, a detailed study of 173 plant species representing 145 genera under 70 families were recorded through baseline floristic survey in four selected sacred groves, to know the importance of biodiversity status and vegetation characteristics.
Abstract: The people of Manipur, a state in northeast India, follow ancestral worship and animism in the form of deity worship, with the central focus on worship in forest patches. The beliefs and taboos associated with the Sylvan deities (Umanglais) in the forest patches are restricted to any sort of disturbance of flora and fauna. These social boundaries help to conserve the entire organism as a whole, which stand the concept of sacred groves. The pleasing of deities is performed every year by the Meiteis, a dominant community of Manipur, in honour of the deities and to gain their favour. Indigenous cultural and rituals practices of the local people in sacred groves serve as a tool for conserving biodiversity. Sacred groves are distributed over a wide ecosystem and help in conservation of rare and endemic species. Well-preserved sacred groves are store houses of valuable medicinal and other plants having high economic value, and serve as a refuge to threatened species. One hundred and sixty-six sacred groves were inventoried in Manipur valley that comprises Imphal east, Imphal west, Thoubal and Bishnupur districts of the state. Detailed studies were carried out in four selected sacred groves, to know the importance of biodiversity status and vegetation characteristics. A total of 173 plant species representing 145 genera under 70 families were recorded through baseline floristic survey. The species diversity indices were compared among the four studied groves. The vegetation composition and community characteristics were recorded. Ethnobotanical uses of species were examined, which reveal that 96% of the species were used as medicine for the treatment of various ailments. Utilization of herbal medicine by the Meiteis is closely related to the cultural and ritual practices. A few of the medicinal plants which have disappeared from the locality are now confined only to the groves. Socio-cultural aspects were investigated taking into account the attitudes of local people, which indicate social beliefs and taboo are eroding, simultaneously degrading the degree of protection of sacred groves. Therefore, conservation measures of sacred groves need to be formulated considering the factor of degradation and the basic necessities of the local people. Until and unless a viable option is provided to the local people (especially those who habitat nearby the adjoining areas) for sustaining their economic condition, no step for conservation of biodiversity will be successful.
96 citations
TL;DR: The higher value of the counterion binding constant for AOT has been reported for the first time and is shown to be due to a change in the shape of the AOT micelles around c*.
95 citations
TL;DR: In the electronic absorption, fluorescence and resonance Raman studies of rhodamine 6G laser dye dispersed in the polymethylcyanoacrylate matrix, band maxima are red shifted compared to solution and Raman spectra show some new bands.
72 citations
TL;DR: In this article, it was shown that if cosmic dark energy behaves like a fluid with equation of state p = w ρ (p and ρ being pressure and energy density respectively) as well as generalized Chaplygin gas simultaneously, big rip or big smash problem does not arise even for equation w − 1.
72 citations
TL;DR: The triphenyltin(IV) complexes of 4-[((E)-1-{2-hydroxy-5-[(E)-2-(2-carboxyphenyl)-1diazenyl]phenyl}methylidene)amino]aryls (aryls) have been synthesized and characterized by 1H-, 13C-, 119Sn-NMR, ESI mass spectrometry, IR and 119mSn Mossbauer spectroscopic techniques in combination with elemental analysis.
62 citations
TL;DR: It was found that BFMI was significantly associated with SRM after adjusting for age, income and FFMI, and the relationship between FFMI and morbidity was not clearly perceptible, suggesting that BMI may not always provide accurate information about the variation in body fat and body composition that is associated with morbidity.
Abstract: This paper deals with BMI and morbidity in relation to body-fat mass (BFM) and fat-free mass (FFM). The analysis was based on cross-sectional data concerning the age, household income, anthropometry and morbidity of 575 males aged 18-59 years from a rural community in North-East India. Data on morbidity were based on the self-reported morbidity (SRM) of the subjects during the last 4 weeks before the survey, whereas data on BMI and body composition were estimated from anthropometry. It was found that SRM was significantly associated with age and income. However, the relationship between BMI and SRM was not significant after adjusting for age and income. Separating the BMI into body-fat mass index (BFMI being BFM in kg divided by height squared in metres) and fat-free mass index (FFMI being FFM in kg divided by height squared in metres), it was found that BFMI was significantly associated with SRM after adjusting for age, income and FFMI. The subjects with a low ( 5.0kg/m 2 ) BFMI than in those with a normal BFMI (odds ratio 3.9, 95 % CI 1.3, 9.8). However, the relationship between FFMI and morbidity was not clearly perceptible. It is therefore speculated that BMI may not always provide accurate information about the variation in body fat and body composition that is associated with morbidity.
60 citations
TL;DR: The study revealed that the leaves of Psidium guajava, Houttuynia cordata and stalk of Lasia spinosa possess a profound anticestodal efficacy as evident by the mean mortality time of R. echinobothrida following exposure to 5 - 40 mg/ml concentration of these plant extracts.
Abstract: The anticestodal efficacy of nine plants that are used in the indigenous system of medicine by Naga tribes in north-east India to cure intestinal-helminth parasitic infections was tested employing Raillietina echinobothrida, a tapeworm of poultry, as a model test parasite. The study revealed that the leaves of Psidium guajava, Houttuynia cordata and stalk of Lasia spinosa possess a profound anticestodal efficacy as evident by the mean mortality time of R. echinobothrida which ranged from 1 to 3.66 hrs, following exposure to 5 - 40 mg/ml concentration of these plant extracts. Moderate activity was recorded for the leaves of Clerodendrum colebrookianum, Lasia spinosa and Centella asiatica, while Curcuma longa, Cinnamomum cassia, Gynura angulosa, Lasia spinosa (stem) and Aloe vera revealed a negligible degree of anticestodal activity.
60 citations
TL;DR: The results provide cause for concern over the status of genetics education in India and the nature of students' conceptual understandings and possible reasons for the observed lack of understanding are discussed.
Abstract: Since the work of Watson and Crick in the mid-1950s, the science of genetics has become increasingly molecular. The development of recombinant DNA technologies by the agricultural and pharmaceutical industries led to the introduction of genetically modified organisms (GMOs). By the end of the twentieth century, reports of animal cloning and recent completion of the Human Genome Project (HGP), as well techniques developed for DNA fingerprinting, gene therapy and others, raised important ethical and social issues about the applications of such technologies. For citizens to understand these issues, appropriate genetics education is needed in schools. A good foundation in genetics also requires knowledge and understanding of topics such as structure and function of cells, cell division, and reproduction. Studies at the international level report poor understanding by students of genetics and genetic technologies, with widespread misconceptions at various levels. Similar studies were nearly absent in India. In this study, I examine Indian higher secondary students' understanding of genetic information related to cells and transmission of genetic information during reproduction. Although preliminary in nature, the results provide cause for concern over the status of genetics education in India. The nature of students' conceptual understandings and possible reasons for the observed lack of understanding are discussed.
54 citations
TL;DR: In this paper, the diorganotin(IV) compounds, [Me2SnL2(OH2)]2 (1), [nBu2snL2[OH2]2 (2), [mBu2nL1]3
53 citations
TL;DR: Canonical analysis shows a notable cumulative impact of six abiotic factors on richness, density and diversity of the rotifer communities of the lower Assam valley of the Brahmaputra river basin.
Abstract: The rotifer communities of 15 acidic – alkaline and soft – marginally hard water floodplain lakes of the lower Assam valley of the Brahmaputra river basin, characterized by low ionic concentrations, reveal 164 species (178 taxa) belonging to 39 genera and 20 families and represent the richest biodiversity known to date in these ecotones of the Indian subcontinent. Nine species are new to the Indian Rotifera. Cosmopolitan (59.7%) > pantropical (15.2%) > cosmotropical (12.2%) species dominate the taxocoenosis. Biogeographically interesting elements constitute a notable component (13.4%); important members of this category include six Oriental, two Australasian and seven Palaeotropical species. The examined fauna depicts a tropical character with predominance of Lecanespp. (28.0%). Littoral or periphytic rotifers (76.2%) dominate the planktonic species. Rotifers comprise a dominant qualitative (67–103, 79.1 ± 11.0 species) and an important quantitative (mean: 41.1–65.9%) component of zooplankton in all floodplain lakes, register a moderate diversity (mean: 2.036–2.642), low dominance (mean: 0.019–0.216) and high evenness (mean: 0.840–0.893). The examined material indicates several interesting acidophilous elements. Richness depicts significant inverse correlation with pH. Water temperature, conductivity, dissolved oxygen and alkalinity record significant direct relationships with the rotifer abundance. Diversity is influenced by abundance and is also directly correlated with water temperature and conductivity. Canonical analysis shows a notable cumulative impact of six abiotic factors on richness, density and diversity.
51 citations
TL;DR: The tetrafluoroborate salt of as discussed by the authors was characterized by FT-IR and FT-NMR spectroscopy as well as analytical data using single crystal X-ray diffraction studies.
TL;DR: The homolytic C-H bond dissociation enthalpies (BDEs) of toluene and its para- and meta-substituted derivatives have been estimated by using the (RO)B3LYP/6-311++G(2df,2p)//(U)B 3LYP / 6-311G(d,p) procedure and are found to be in good agreement.
Abstract: The homolytic C-H bond dissociation enthalpies (BDEs) of toluene and its para- and meta-substituted derivatives have been estimated by using the (RO)B3LYP/6-311++G(2df,2p)//(U)B3LYP/6-311G(d,p) procedure. The performance of two other hybrid functionals of DFT, namely, B3PWP91 and O3LYP, has also been evaluated using the same basis sets and molecules. Our computed results are compared with the available experimental values and are found to be in good agreement. The (RO)B3LYP and (RO)O3LYP procedures are found to produce reliable BDEs for the C-H bonds in toluene and the C-X (X = F, Cl) bond in alpha-substituted toluene (C6H5-CH2X) and their substituted derivatives. The substituent effect on the BDE values has been analyzed in terms of the ground-state effect and the radical effect. The effect of polarization of the C-H bond on the substituent effect is also analyzed. The BDE(C-H) and BDE(C-X) values for alpha-substituted (X = F and Cl) toluenes with a set of para substituents are presented for the first time.
TL;DR: In this article, three diorganotin(IV) complexes of the type, [R 2 Sn(L a H)(L b H)] (R = n Bu or Me and, L a H and L b H are two different 5-[( E )-2-(aryl)-1-diazenyl]-2-hydroxybenzoate residues; a: aryl= 4′-Cl-(held constant) and b: ayrl= ǫ-Me or 4′ -Br) have been prepared either by reacting n Bu 2 Sn
TL;DR: The indenyl and pentamethylcyclopentadienyl ruthenium(II) complexes were fully characterized on the basis of microanalyses, FT-IR and NMR spectroscopy as mentioned in this paper.
Journal Article•
TL;DR: A critical review of information available on various components of the adrenergic signal transduction cascades involved in the regulation of melatonin synthesis is given.
Abstract: Rhythmic neural outputs from the hypothalamic suprachiasmatic nucleus (SCN), which programme the rhythmic release of norepinephrine (NE) from intrapineal nerve fibers, regulate circadian rhythm of melatonin synthesis. Increased secretion of NE with the onset of darkness during the first half of night stimulates melatonin synthesis by several folds. NE binds to both alpha1- and beta-adrenergic receptors present on the pinealocyte membrane and initiates adrenergic signal transduction via cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) generating pathways. The NE-induced adrenergic signal transduction switches 'on' melatonin synthesis during the early hours of night by stimulating expression of the rate-limiting enzyme of melatonin synthesis, N-acetyltransferase (AA-NAT) via cAMP-protein kinase A (PKA)-cAMP response element binding protein (CREB)-cAMP response element (CRE) pathway as well as by increasing AA-NAT activity via cAMP-PKA-14-3-3 protein pathway. Simultaneously, adrenergically-induced expression of inducible cAMP early repressor (ICER) negatively regulates aa-nat gene expression and controls the amplitude of melatonin rhythm. In the second half of night, increased release of acetylcholine from central pinealopetal projections, inhibition of NE secretion by SCN, withdrawal of adrenergic inputs and reversal of events that took place in the first half lead to switching 'off' of melatonin synthesis. Adrenergic signal transduction via cGMP-protein kinase G (PKG)-mitogen activated protein kinase (MAPK)-ribosomal S6 kinase (RSK) pathway also seems to be fully functional, but its role in modulation of melatonin synthesis remains unexplored. This article gives a critical review of information available on various components of the adrenergic signal transduction cascades involved in the regulation of melatonin synthesis.
TL;DR: In this article, the impact of human activities such as shifting agriculture and horticultural practices on temporal and spatial changes in microbial biomass and dehydrogenase and urease activities in soil was analyzed in the Nokrek biosphere reserve of Meghalaya in north-east India.
Abstract: The present study conducted in the Nokrek biosphere reserve (BR) of Meghalaya in north-east India aimed at analyzing the impact of human activities such as shifting agriculture (‘Jhum’) and horticultural practices on temporal and spatial changes in microbial biomass and dehydrogenase and urease activities in soil. Microbial biomass-C (MBC) and -N(MBN) as well as dehydrogenase and urease activities were significantly (P
TL;DR: In this article, the authors derived sum rules for neutralino and chargino masses in different representations of SU(5) which lead to different nonuniversal boundary conditions for the gaugino masses at the unification scale.
Abstract: Grand unified theories can lead to nonuniversal boundary conditions for the gaugino masses at the unification scale. We consider the implications of such nonuniversal boundary conditions for the composition of the lightest neutralino as well as for the upper bound on its mass in the simplest supersymmetric grand unified theory based on the SU(5) gauge group. We derive sum rules for neutralino and chargino masses in different representations of SU(5) which lead to different nonuniversal boundary conditions for the gaugino masses at the unification scale. We also consider the phenomenological implications of the nonuniversal gaugino masses arising from a grand unified theory in the context of large hadron collider. In particular we investigate the detection of heavy neutral Higgs bosons H{sup 0}, A{sup 0}from H{sup 0}, A{sup 0}{yields}{chi}-tilde{sub 2}{sup 0}{chi}-tilde{sub 2}{sup 0}{yields}4l and study the possibilities of detecting the neutral Higgs bosons in cascade decays, including the decays {chi}-tilde{sub 2}{sup 0}{yields}h{sup 0}(H{sup 0},A{sup 0}){chi}-tilde{sub 1}{sup 0}{yields}bb{chi}-tilde{sub 1}{sup 0}.
TL;DR: Toxicity studies of the tributyltin(IV) complexes of the 4]-((E)-1-{2-hydroxy-5-[(E)-2-(2-carboxyphenyl)1-diazenyl]phenyl}methylidene)amino]aryls on the second larval instar of the Aedes aegypti and Anopheles stephensi mosquito larvae are also reported as discussed by the authors.
Abstract: (Bu3Sn[O2CC6H4{N N(C6H3-4-OH(C(H) NC6H4OCH3-4))}-o])n reveals a polymeric structure. Toxicity studies of the tributyltin(IV) complexes of the 4-[((E)-1-{2-hydroxy-5-[(E)-2-(2-carboxyphenyl)1-diazenyl]phenyl}methylidene)amino]aryls on the second larval instar of the Aedes aegypti and Anopheles stephensi mosquito larvae are also reported. The LC50 values indicate that the complexes are effective larvicides, which range from a low of 0.36 ppm to a high of 0.69 ppm against the Ae. aegypti larvae and between 0.82 and 1.17 ppm against the An. stephensi larvae. Copyright 2005 John Wiley & Sons, Ltd.
TL;DR: The reaction of the complex [{(η6-C6Me6)Ru(μ-Cl)Cl}2] 1 with sodium azide ligand gave two new dimers of the composition as mentioned in this paper, depending upon the reaction conditions.
TL;DR: In this article, a cyclic centrosymmetric dinuclear moiety linked into extended chains by pairs of long Sn⋯O contacts was identified and their structures differ primarily in the packing arrangement afforded by the benzyl groups.
TL;DR: The study suggests that the aerial shoots of T. repens.
Abstract: Trifolium repens. L. is an herbal plant that is used in the folk medicine of the Naga tribes of India as a deworming remedy. This study deals with evaluating its anticestodal activity using experim...
TL;DR: In this paper, the shape of decaying part and photo count distribution of non-decaying part are determined in 21 spectral decompositions of a biophoton signal obtained from interference and long pass filters.
TL;DR: In this paper, the authors consider threshold effects on neutrino masses and mixings in a recently proposed model for understanding large solar and atmospheric mixing angles using radiative magnification for the case of quasidegenerate neutrinos.
Abstract: We consider threshold effects on neutrino masses and mixings in a recently proposed model for understanding large solar and atmospheric mixing angles using radiative magnification for the case of quasidegenerate neutrinos We show that the magnitude of the threshold effects is sufficient to bring concordance between the predictions of this model and latest data from KamLAND and SNO on observations of neutrino oscillations
TL;DR: This work deals with a theoretical study of the (CH...C)- hydrogen bonds in CH4, CH3X, and CH2X2 (X = F, Cl) complexed with their homoconjugates and heteroconjugate carbanions, indicating an important electronic reorganization in the two partners.
Abstract: This work deals with a theoretical study of the (CH···C)- hydrogen bonds in CH4, CH3X, and CH2X2 (X = F, Cl) complexed with their homoconjugate and heteroconjugate carbanions. The properties of the complexes are calculated with the B3LYP method using the 6-311++G(d,p) or 6-311++G(2df,2p) basis sets. The deprotonation enthalpies (DPE) of the CH bond or the proton affinities of the carbanions (PA(C-) are calculated as well. All the systems with the exception of the CH4···CHCl2- one are characterized by a double minimum potential. In some of the complexes, the (CHb···C)- hydrogen bond is linear. In other systems, such as CH3F···CH2F- and CH3F···CHF2-, there is a large departure from linearity, the systems being stabilized by electrostatic interactions between the nonbonded H of the neutral molecule and the F atom of the carbanion. In the transition state, the (CHb···C)- bond is linear, and there is a large contraction of the intermolecular C···C distance. The binding energies vary within a large range, from ...
TL;DR: In this article, a study was carried out to understand whether fine root growth and N mineralization are synchronized in such a manner that helps to conserve N in the humid subtropical forest ecosystem, and to assess whether or not these processes are influenced by human disturbance.
Abstract: The present study was carried out to understand whether fine root growth and N mineralization are synchronized in such a manner that helps to conserve N in the humid subtropical forest ecosystem, and to assess whether or not these processes are influenced by human disturbance. The study was conducted in two pairs of undisturbed and disturbed stands of subtropical humid forest in the Jaintia hill district of Meghalaya, northeast India. The amount of fine root (540–754 g m−2) and coarse root (307–387 g m−2) mass in the protected stands was higher than those recorded (fine root 422–466 g m−2, coarse root 247–305 g m−2) in the unprotected stands. The total annual root production was also higher in the protected stands (1,102–1,242 g m−2) than the unprotected stands (890–940 g m−2). The mean concentration of NH4+–N and NO3−–N was higher in the protected stands than in the unprotected stands. The inorganic-N (NH4+–N and NO3−–N) concentration was markedly high during the dry period and low during the wet period in all the stands. Inorganic-N concentration, nitrification and N mineralization rates were significantly (P<0.01) higher in the surface (0–10 cm) than the subsurface (10–20 cm) layer. The low and high N mineralization rates observed during the dry and wet periods, respectively, coincided with the lean and peak periods of fine root mass. Disturbance in the forests caused a reduction in fine root mass as well as in N mineralization.
TL;DR: In this paper, a series of mononuclear indenyl and pentamethylcyclopentadienyl ruthenium(II) complexes of formulation [(η5-L3)Ru(PPh3)(L2)]X, (where L3=indenyl; X=PF6 or BF4 and L2=azine ligands) have been prepared by the reaction of [(∷5L3]Ru(pPh3)2(CH3CN)]X with the appropriate azine ligands in methanol or dichloromet
TL;DR: While no significant impact of abiotic factors was recorded on zooplankton density, rainfall alone was the most important factor that influenced net plankton and various groups of phytoplankon.
Abstract: A pioneering limnological investigation was carried out in Bhutan in a small peat bog in the Trashiyangtse district (1950 m above sea level) from February 2000 to January 2002. The sampled pond water had low transparency (55.0–95.0 cm), was typically acidic (pH 5.69–6.58) with soft water (alkalinity, 11.0–36.0 mg/l; total hardness, 10.0–34.0 mg/l), and had low to moderate specific conductivity (17.0–62.0 µS/cm). Further, moderate Na (2.0–6.8 mg/l), K (1.8–13.5 mg/l), sulphate (0.85–2.99 mg/l), and silicate (2.5–15.0 mg/l) concentrations as well as low nutrient levels such as phosphate (0.006–0.170 mg/l) and nitrate (0.003–0.180 mg/l) characterize the water in the peat bog. The recorded net plankton comprised 27 species of phytoplankton and 49 species of zooplankton, with the latter indicating greater homogeneity and breaking down into Rotifera (23 species) > Cladocera (13 species) > Rhizopoda (8 species) > Copepoda (3 species) > Ostracoda = Nematoda (1 species each). On the other hand, the net plankton density ranged between 93 and 692 number/l (n/l) with numerical dominance by phytoplankton (68.5% ± 12%), of which Chlorophyceae were predominant (90 ± 63 n/l). Zooplankton showed moderately high diversity (2.745 ± 0.293) and evenness (0.925 ± 0.049) and exhibited almost equal abundance of four recorded groups, namely Cladocera (20 ± 15 n/l) > Rotifera (15 ± 6 n/l) > Copepoda (14 ± 7 n/l) > Rhizopoda (14 ± 4 n/l). While no significant impact of abiotic factors was recorded on zooplankton density, rainfall alone was the most important factor that influenced net plankton and various groups of phytoplankton. Comments on some comparative limnological attributes are also made with similar as well as different habitats in the nearby Himalayan countries.
TL;DR: In this article, the molecular structure of a representative complex, (η5-C5Me5)Ru(PPh3)(C5H4N-2-CH N-C6H4-p-Cl)]PF6, has been established by X-ray crystallography.
TL;DR: The presence of prominent swellings in some sensilla and shrinkage in others suggests that the leaf extract affects different systems through different mechanisms, and the possible use of the plant as a potential biopesticide against certain insect pests is discussed.
Abstract: Scanning electron microscopic study revealed some remarkable adverse effects of Eupatorium adenophorum Spreng leaf extract on cuticular and antennal sensilla of the mustard aphid, Lipaphis erysimi Kalt. The study appears to be the first of its kind in providing evidence on toxic property of the plant on certain agricultural pests, although the indigenous tribes of the region know the insecticidal property of the plant for a long time. The study further provides indications regarding the neurotoxic nature of the leaf extract since it has caused abnormalities in the sensory structures. The presence of prominent swellings in some sensilla and shrinkage in others suggests that the leaf extract affects different systems through different mechanisms. The possible use of the plant as a potential biopesticide against certain insect pests is discussed.
TL;DR: In this article, a triclinic space group (P21/c) was used to characterize the molecular structures of ruthenium dimeric complexes of the type (η6-C6Me6)Ru(κ2-O,O′-R1COCHCOR2)N3.