Showing papers by "North Eastern Hill University published in 2014"

Reconstruction of gene co-expression network from microarray data using local expression patterns

Abstract: Biological networks connect genes, gene products to one another. A network of co-regulated genes may form gene clusters that can encode proteins and take part in common biological processes. A gene co-expression network describes inter-relationships among genes. Existing techniques generally depend on proximity measures based on global similarity to draw the relationship between genes. It has been observed that expression profiles are sharing local similarity rather than global similarity. We propose an expression pattern based method called GeCON to extract Ge ne CO-expression N etwork from microarray data. Pair-wise supports are computed for each pair of genes based on changing tendencies and regulation patterns of the gene expression. Gene pairs showing negative or positive co-regulation under a given number of conditions are used to construct such gene co-expression network. We construct co-expression network with signed edges to reflect up- and down-regulation between pairs of genes. Most existing techniques do not emphasize computational efficiency. We exploit a fast correlogram matrix based technique for capturing the support of each gene pair to construct the network. We apply GeCON to both real and synthetic gene expression data. We compare our results using the DREAM (Dialogue for Reverse Engineering Assessments and Methods) Challenge data with three well known algorithms, viz., ARACNE, CLR and MRNET. Our method outperforms other algorithms based on in silico regulatory network reconstruction. Experimental results show that GeCON can extract functionally enriched network modules from real expression data. In view of the results over several in-silico and real expression datasets, the proposed GeCON shows satisfactory performance in predicting co-expression network in a computationally inexpensive way. We further establish that a simple expression pattern matching is helpful in finding biologically relevant gene network. In future, we aim to introduce an enhanced GeCON to identify Protein-Protein interaction network complexes by incorporating variable density concept.

Anthelmintic efficacy of gold nanoparticles derived from a phytopathogenic fungus, Nigrospora oryzae.

Abstract: Exploring a green chemistry approach, this study brings to the fore, the anthelmintic efficacy of gold nanoparticles, highlighting the plausible usage of myconanotechnology. Gold nanoparticles of ∼6 to ∼18 nm diameter were synthesized by treating the mycelia-free culture filtrate of the phytopathogenic fungus with gold chloride. Their size and morphology were confirmed by UV-Vis spectroscopy, DLS data, AFM and TEM images. The XRD studies reveal a crystalline nature of the nanoparticles, which are in cubic phase. The FTIR spectroscopic studies before and after the formation of nanoparticles show the presence of possible functional groups responsible for the bio-reduction and capping of the synthesized gold nanoparticles. The latter were tested as vermifugal agents against a model cestode Raillietina sp., an intestinal parasite of domestic fowl. Further, ultrastructural and biochemical parameters were used to corroborate the efficacy study.

Bioactive compounds in bamboo shoots: health benefits and prospects for developing functional foods

Abstract: Summary Juvenile bamboo shoots have long been used as food and in traditional medicine in many Asian countries, but scientific evidences of its health benefits have been highlighted recently. According to ancient Chinese medicinal books, the consumption of young shoots helps in improving digestion, relieving hypertension, sweating, preventing cardiovascular diseases and cancer. The young shoots are delicious and rich in nutrient components such as proteins, carbohydrates, minerals and vitamins and bioactive compounds. The health benefits of the young shoots are attributed to the presence of bioactive compounds mainly phenols, phytosterols and dietary fibres, which play a potential role in health promotion and providing protection against many chronic and degenerative diseases. Phenolic compounds in bamboos have multiple biological effects such as antioxidation, anti-ageing, antifatigue, antimicrobial and prevention of cardiovascular diseases. Dietary fibres and phytosterols have a beneficial effect on lipid profile and bowel function and reduce total serum cholesterol and low-density lipoprotein cholesterol level. This study discusses the bioactive compounds in bamboo shoots and how, due to its nutritive value and health benefits, the shoots can be utilised as an ingredient in the development of functional foods.

Kinetic parameters for nutrient enhanced crude oil biodegradation in intertidal marine sediments.

Abstract: Availability of inorganic nutrients, particularly N and P, is often a primary control on crude oil hydrocarbon degradation in marine systems. Nevertheless, there is a paucity of information on fundamental kinetic parameters for nutrient enhanced crude oil biodegradation that can be used to model the fate of crude oil in bioremediation programmes that use inorganic nutrient addition to stimulate oil biodegradation. Here we report fundamental kinetic parameters (Ks and qmax) for nitrate- and phosphate-stimulated crude oil biodegradation under nutrient limited conditions and with respect to crude oil, under conditions where N&P are not limiting. Crude oil degradation was limited by both N&P availability. When N was added alone maximum rates of CO2 production measured were 3.94±0.46 µmol CO2 /g wet sediment/day. However when the same levels of N were added in the presence of 0.5% P w/w of oil (1.6 μmol P/g wet sediment) maximum rates of measured CO2 production more than doubled (11.52±0.72 µmol CO2 /g wet sediment/day). Ks and qmax estimates for N (in the form of sodium nitrate) when P was not limiting were 1.57±0.56 µmol/g wet sediment and 10.57±0.63 µmol CO2 /g wet sediment/day respectively. The corresponding values for P were 80 nmol/g wet sediment and 8.76±1.15 µmol CO2 /g wet sediment/day. The qmax values with respect to N and P were not significantly different (P< 0.05). Analysis of bacterial 16S rRNA genes indicated that Alcanivorax spp. were selected in these marine sediments with increasing inorganic nutrient concentration, whereas Cycloclasticus spp. were more prevalent at lower inorganic nutrient concentrations. These data suggest that simple empirical estimates of the proportion of nutrients added relative to crude oil concentrations may not be sufficient to guarantee successful crude oil bioremediation in oxic beach sediments. The data we present also help define the maximum rates and hence timescales required for bioremediation of beach sediments.

Evaluation of the antimicrobial potency of silver nanoparticles biosynthesized by using an endophytic fungus, Cryptosporiopsis ericae PS4.

Abstract: In the present study, silver nanoparticles (AgNPs) with an average particle size of 5.5 ± 3.1 nm were biosynthesized using an endophytic fungus Cryptosporiopsis ericae PS4 isolated from the ethno-medicinal plant Potentilla fulgens L. The nanoparticles were characterized using UV-visible spectrophotometer, transmission electron microscopy (TEM), scanning electron microscopy (SEM), selective area electron diffraction (SAED), and energy dispersive X-ray (EDX) spectroscopy analysis. Antimicrobial efficacy of the AgNPs was analyzed singly and in combination with the antibiotic/antifungal agent chloramphenicol/fluconazole, against five pathogenic microorganisms-Staphylococcus aureus MTCC96, Salmonella enteric MTCC735, Escherichia coli MTCC730, Enterococcus faecalis MTCC2729, and Candida albicans MTCC 183. The activity of AgNPs on the growth and morphology of the microorganisms was studied in solid and liquid growth media employing various susceptibility assays. These studies demonstrated that concentrations of AgNPs alone between 10 and 25 μM reduced the growth rates of the tested bacteria and fungus and revealed bactericidal/fungicidal activity of the AgNPs by delaying the exponential and stationary phases. Examination using SEM showed pits and ruptures in bacterial cells indicating fragmented cell membrane and severe cell damage in those cultures treated with AgNPs. These experimental findings suggest that the biosynthesized AgNPs may be a potential antimicrobial agent.

Theoretical investigation of atmospheric chemistry of volatile anaesthetic sevoflurane: reactions with the OH radicals and atmospheric fate of the alkoxy radical (CF3)2CHOCHFO: thermal decomposition vs. oxidation

Abstract: A theoretical study on the mechanism and kinetics of the gas phase reactions of a volatile anaesthetic compound (CF3)2CHOCH2F (Sevoflurane) with the OH radicals has been carried out using the hybrid HF–density functional M06-2X/6-31+G(d,p) method. Three conformations are predicted for the Sevoflurane molecule. Among the three conformers, the most stable one is considered for a detailed study. Reaction profiles are modeled including the formation of pre-reactive and post-reactive complexes at entrance and exit channels. Single point energy calculations have been performed by using the 6-311++G(d,p) basis set. The hydrogen abstraction from the –CH2F group is found to be the dominant reaction channel for hydrogen abstraction by OH radicals. Theoretically the calculated rate constant is found to be in good agreement with the experimentally measured ones. Using group-balanced isodesmic reactions, the standard enthalpies of formation for (CF3)2CHOCH2F, (CF3)2COCH2F and (CF3)2CHOCHF radicals are also reported for the first time. The atmospheric fate of the alkoxy radical, (CF3)2CHOCHFO, is also investigated for the first time using the same level of theory. Out of four prominent plausible decomposition channels including oxidation, our results clearly point out that reaction with O2 is the dominant path for the decomposition of (CF3)2CHOCHFO in the atmosphere involving the lowest energy barrier which is in accord with recent experimental findings.

Studies on Biosynthesis of Antimicrobial Silver Nanoparticles Using Endophytic Fungi Isolated from the Ethno-medicinal Plant Gloriosa superba L.

Abstract: Two endophytic fungi isolated from the ethno-medicinal plant Gloriosa superba L. were used for the in vitro biosynthesis of silver nanoparticles (AgNPs). The endophytic fungi were identified as Alternaria solani GS1 and Penicillium funiculosum GS2 based on their ITS regions of rRNA gene sequences. The silver nanoparticles obtained were characterized by UV–visible spectroscopy and transmission electron microscopy. Silver nanoparticles of the size 5–20 nm biosynthesized by A. solani GS1were found to be at peak at 415 nm whereas the AgNPs of the size 5–10 nm biosynthesized using P. funiculosum GS2 showed a maximum peak at 403 nm. An evident superiority of the antimicrobial potency, as denoted by the zone of inhibition by biosynthesized AgNPs using P. funiculosum GS2 compared to that by A. solani GS1, was observed when the nanoparticles were used against three different bacterial strains (Streptococcus pyogenes MTCC1925, Escherichia coli MTCC730 and Enterococcus faecalis MTCC2729) and a fungal strain (Candida albicans MTCC183). The present study elucidates the efficacy of the AgNPs synthesized by endophytic fungi against the three tested bacterial strains as well as the fungal strain C. albicans indicating their potency of bioprospection for medicinal usage.

Application of genetics and genomics towards Capsicum translational research

Abstract: Capsicum species commonly known as Chili peppers are economically important group of plants belonging to the Solanaceae family. Of the 38 species reported, only six species namely, Capsicum annuum, C. assamicum, C. baccatum, C. frutescence, C. chinense and C. pubescens are cultivated. They are very important component of the human being as peppers are used as vegetables, spices, and a coloring agent and for medicinal purposes. Based on pungency trait which is due to the presence of a group of compounds known as capsaicinoids, cultivated capsicums are classified into sweet peppers and hot peppers. Although conventional breeding and classical genetic analysis were successful in estimating the number of genes for economically important traits governed by few major genes and their incorporation in the breeding programme, the advent of molecular markers and recently developed next generation sequencing technologies supplemented greatly in dissecting the genetic and molecular basis of economically important traits in the capsicum genome for applied research. Here in this review, we tried to highlight the use of molecular markers, comparative mapping and advanced genomics technologies and their integrated use in the translational research of cultivated Capsicums.

Synthesis and characterization of some water soluble Zn(II) complexes with (E)-N-(pyridin-2-ylmethylene)arylamines that regulate tumour cell death by interacting with DNA.

Abstract: The synthesis and spectroscopic properties of nine water soluble zinc(II) complexes of (E)-N-(pyridin-2-ylmethylene)arylamines (Ln) with the general formula [Zn(X)2(Ln)] (X = Cl−, Br−, I−; (1–8)) and [Zn(μ-N3)(N3)(L3)]2 (9) are reported. The complexes were characterized by elemental analysis and their spectroscopic properties were studied using UV-Visible, fluorescence, IR and 1H NMR spectroscopies. The solid state structures of zinc(II) complexes 2–4 and 6–9 were established by single crystal X-ray crystallography. The majority of the structures are mononuclear with tetra-coordinate zinc centres (2–4, 6 and 7) except where L carries an additional donor atom capable of coordinating zinc (8), in which case the zinc atom has a distorted square pyramidal geometry. The centrosymmetric molecule of [Zn(μ-N3)(N3)(L3)]2 (9) is binuclear with the zinc atoms in a trigonal bipyramidal coordination environment. In general, the dichlorozinc derivatives 1, 3–5 and 8 exhibited moderately elevated in vitro cytotoxic potency towards the human epithelial cervical carcinoma (HeLa) cell line, with 4 as the best performer (IC50 value of 18 μM). Apoptosis-inducing activity, assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, showed that the zinc complexes interacted with DNA and thereby interfered the DNA binding of several transcription factors to its promoter sites, thus inhibiting gene transcription required for the biological activity of cells.

Epiphytic and endophytic bacteria that promote growth of ethnomedicinal plants in the subtropical forests of Meghalaya, India

Abstract: The present study was aimed to investigate the endophytic and epiphytic bacteria associated with selected ethnomedicinal plants from the pristine subtropical forests of Meghalaya and analyse them for plant growth promotion and antagonistic ability. This study is an attempt to explore plant associated bacteria which are beneficial to host plants, and thus aid in the conservation of ethnomedicinal plants of the studied subtropical forests, which are dwindling due to exploitation. The plant growth promotion parameters like indole acetic acid (IAA) production, mineral phosphate solubilisation, acid phosphatase activity, presence of 1-aminocyclopro- pane-1-carboxylic acid deaminase (ACC) gene, nitrogen fixation, cellulose digestion, chitin and pectin degrada- tion were screened among the isolates. The study revealed significant differences in bacterial population not only between the epiphytic and endophytic microhabitats, but also amongst the host plants. Out of the 70 isolated plant associated bacteria, Bacillus sp., Serratia sp., Pseudomonas sp., Pantoea sp., and Lysinibacillus sp. showed potent plant growth promotion properties. Bacillus siamensis C53 and B. subtilis cenB showed significant antagonistic activity against the tested pathogens. This study indicated the isolates inhabiting the plants prevalent in the subtropical sacred forests could be explored for use as plant growth promoters while practising the cultiva- tion and conservation of ethnomedicinal plants. Rev. Biol. Trop. 62 (4): 1295-1308. Epub 2014 December 01.

Traditional healing with animals (zootherapy) by the major ethnic group of karbi anglong district of assam, india

Abstract: Objective: To survey and document the traditional knowledge related to medicinal uses of animals among the ethnic groups in Karbi Anglong district of Assam. Methods: A long term field survey was conducted from July 2008 to October 2009 by performing personal interviews through structured questionnaire with more than 500 respondents, who provided information regarding the use of different animals and their products in their traditional medicine. Most of the information on the use of various animals in traditional medicine by them was provided by elderly people in the age groups of more than 50 years. Results: A total of 48 different animals were recorded to be used for different ethno-medical purposes against various diseases, including tuberculosis, asthma, cancer, paralysis, jaundice, leprosy, toothache, rabies, dysentery, baldness, rheumatism, arthritis, weakness, piles etc. The highest percentage of animals used for traditional treatment is mammals (about 40%) followed by insects (about 21%) and birds (about 19%). Conclusion: The findings reveal a rich traditional knowledge of indigenous people of Karbi Anglong about the use of animals and their product in traditional medicine. It is suggested that this kind of traditional knowledge should be included into the scientific literature for the conservation and management of medicinal faunistic resources.

The mitochondrial genome of Paragonimus westermani (Kerbert, 1878), the Indian isolate of the lung fluke representative of the family Paragonimidae (Trematoda)

Abstract: Among helminth parasites, Paragonimus (zoonotic lung fluke) gains considerable importance from veterinary and medical points of view because of its diversified effect on its host. Nearly fifty species of Paragonimus have been described across the globe. It is estimated that more than 20 million people are infected worldwide and the best known species is Paragonimus westermani, whose type locality is probably India and which infects millions of people in Asia causing disease symptoms that mimic tuberculosis. Human infections occur through eating raw crustaceans containing metacercarie or ingestion of uncooked meat of paratenic hosts such as pigs. Though the fluke is known to parasitize a wide range of mammalian hosts representing as many as eleven families, the status of its prevalence, host range, pathogenic manifestations and its possible survivors in nature from where the human beings contract the infection is not well documented in India. We took advantage of the whole genome sequence data for P. westermani, generated by Next Generation Sequencing, and its comparison with the existing data for the P. westermani for comparative mt DNA phylogenomic analyses. Specific primers were designed for the 12 protein coding genes with the aid of existing P. westermani mtDNA as the reference. The Ion torrent next generation sequencing platform was harnessed to completely sequence the mitochondrial genome, and applied innovative approaches to bioinformatically assemble and annotate it. A strategic PCR primer design utilizing the whole genome sequence data from P. westermani enabled us to design specific primers capable of amplifying all regions of the mitochondrial genome from P. westermani. Assembly of NGS data from libraries enriched in mtDNA sequence by PCR gave rise to a total of 11 contigs spanning the entire 14.7 kb mt DNA sequence of P. westermani available at NCBI. We conducted gap-filling by traditional Sanger sequencing to fill in the gaps. Annotation of non-protein coding genes successfully identified tRNA regions for the 24 tRNAs coded in mtDNA and 12 protein coding genes. Bayesian phylogenetic analyses of the concatenated protein coding genes placed P. westermani within the family Opisthorchida. The complete mtDNA sequence of P. westermani is 15,004 base pairs long; the lung fluke is the major etiological agent of paragonimiasis and the first Indian representative for the family Paragonimidae to be fully sequenced that provides important genetic markers for ecological, population and biogeographical studies and molecular diagnostic of digeneans that cause trematodiases.

Plant Extracts and Plant-Derived Compounds: Promising Players in Countermeasure Strategy Against Radiological Exposure: A Review

Abstract: Radiation exposure leads to several pathophysiological conditions, including oxidative damage, inflammation and fibrosis, thereby affecting the survival of organisms. This review explores the radiation countermeasure properties of fourteen (14) plant extracts or plant-derived compounds against these cellular manifestations. It was aimed at evaluating the possible role of plants or its constituents in radiation countermeasure strategy. All the 14 plant extracts or compounds derived from it and considered in this review have shown some radioprotection in different in vivo, ex-vivo and or in vitro models of radiological injury. However, few have demonstrated advantages over the others. C. majus possessing antioxidant, anti-inflammatory and immunomodulatory effects appears to be promising in radioprotection. Its crude extracts as well as various alkaloids and flavonoids derived from it, have shown to enhance survival rate in irradiated mice. Similarly, curcumin with its antioxidant and the ability to ameliorate late effect of radiation exposure, combined with improvement in survival in experimental animal following irradiation, makes it another probable candidate against radiological injury. Furthermore, the extracts of P. hexandrum and P. kurroa in combine treatment regime, M. piperita, E. officinalis, A. sinensis, nutmeg, genistein and ginsan warrants further studies on their radioprotective potentials. However, one that has received a lot of attention is the dietary flaxseed. The scavenging ability against radiation-induced free radicals, prevention of radiation-induced lipid peroxidation, reduction in radiation cachexia, level of inflammatory cytokines and fibrosis, are some of the remarkable characteristics of flaxseed in animal models of radiation injury. While countering the harmful effects of radiation exposure, it has shown its ability to enhance survival rate in experimental animals. Further, flaxseed has been tested and found to be equally effective when administered before or after irradiation, and against low doses (≤ 5 Gy) to the whole body or high doses (12-13.5 Gy) to the whole thorax. This is particularly relevant since apart from the possibility of using it in pre-conditioning regime in radiotherapy, it could also be used during nuclear plant leakage/accidents and radiological terrorism, which are not pre-determined scenarios. However, considering the infancy of the field of plant-based radioprotectors, all the above-mentioned plant extracts/plant-derived compounds deserves further stringent study in different models of radiation injury.

Trace Elements Analysis in Drinking Water of Meghalaya by Using Graphite Furnace-Atomic Absorption Spectroscopy and in relation to Environmental and Health Issues

Abstract: Determination of the certain major and trace elements was carried out in drinking water supply scheme in three districts of Meghalaya. This work aims to identify trends resulting in the deterioration of drinking water which is also a potential source of environmental contaminants. About 50 samples, each from one district, were collected both from the source and various tanks and tap. The elements determined are Li, Na, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Rb, Ag, Au, Pb, Cd, Se, Ca, K, and Mg. The pH is slightly lower than neutral pH of 7 while the turbidity is very high even after treatment. The concentrations of Ca and Mg are found to be deficient. The elements Cr, Fe, Co, Ni, Zn, Mo, and Pb decrease after treatment while Mn, Cu, and Cd increase slightly after treatment. Se concentration is found to be much higher than expected. The results were compared with the standard recommendation values for the quality of drinking water. This study provides a general indication of where water-quality constituent concentrations met or exceeded water-quality standards and the data presented in this report will be useful from public health point of view.

Performance of M-MRC receivers over TWDP fading channels

Abstract: An expression of characteristic function of signal-to-noise ratio (SNR) for two waves with diffused power (TWDP) fading channel is derived. Using this expression, the expression for the probability density function (PDF) of the output SNR of maximal ratio combining (MRC) receiver is obtained. Expressions for the performance matrix of MRC receiver over TWDP fading channels are also deduced. PDF based approach is followed to derive expressions of outage probability and average symbol error rate for coherent and non-coherent m-ary modulation schemes. Effects of the number of branches M and the fading parameters K and Δ on the system performance are studied. The results obtained are verified by Monte Carlo simulation.

High-Selective Compact UWB Bandpass Filter With Dual Notch Bands

Abstract: In this letter, a novel high selective UWB band pass filter (BPF) with dual notch bands is presented. UWB BPF is realized using open stub and short stub loaded resonator (SLR). The resonators are realized to incorporate four resonating modes in the UWB passband extending from 3.14 to 10.53 GHz. Two transmission zeroes at 3.01 and 10.68 GHz, near to the UWB passband, increases the selectivity of the filter. Half wavelength long spiral resonators as slots are implemented in ground plane to achieve notch band at 5.13 GHz and an inward folded resonator is placed near to the open SLR to achieve notch at 8.0 GHz. Measured passband insertion loss is within 1.5 dB. The prototype of the proposed UWB BPF is fabricated and measured. Simulated response of the designed BPF agrees well with the measured result.

Identification of Unknown Homeopathic Remedies by Delayed Luminescence

Abstract: A quality control method of highly diluted and potentized homeopathic remedies is important for curing patients applying homeopathic therapy. Lenger detected photons in highly potentized homeopathic remedies by delayed luminescence. The photons of Argentum metallicum 100MK and Cantharis 100MK magnetically bound to their carrier substances ethanol or saccharose were separated by their resonating magnetic field of about 2.06 MHz. The photons of these 100MK potency levels and of their reference substances were determined to be standard values calculated by the B2-values of Bajpai's equation derived from the Hamiltonian equation. The stability of ethanolic Argentum metallicum 100MK and Cantharis 100MK declined to 1/3 of their photons within a month in contrast to saccharose globules with Argentum metallicum 100MK having been stable during the period of these investigations for almost 1 year. Some remedies delivered as CMK potency had been proved to be ethanol. The testing amount of high ethanolic potencies is limited to 40 μl because 80 μl resulted in an attenuation of the photons; 40 μl equal 16 medicated saccharose globules. Six unknown homeopathic remedies could be identified as increasing potency levels of Argentum metallicum from 100MK to 1.000MK which indicates a calibration curve. The homeopathic factories having sent the unknown remedies confirmed the measurements. A quality control of homeopathic remedies is possible by comparing the different B2-values of the remedies and their carrier substances.

Bakers' yeast: an environment benign catalyst for the one-pot synthesis of indolyl chromenes and bisindolyl alkanes

Abstract: A green protocol for one-pot synthesis of pharmacologically important indolyl chromenes and bis(indolyl)alkanes was achieved using Saccharomyces cerevisiae (commonly known as bakers' yeast) as catalyst under room temperature stirring condition. This method is relatively simple, efficient, inexpensive, and environment-friendly.

An Index of Maternal and Child Healthcare Status in India: Measuring Inter- and Intra-State Variations from Capability Perspectives

Abstract: Despite remarkable progress in past few decades India’s current maternal and child mortality levels fall significantly short to attain many of the targets of MDGs. The variation in attainments across and within regions has always been a crucial dimension of Indian concerns. The present paper takes a closer look at the spatial variation of maternal and child healthcare status in India by summarising a set of constituent indicators that are instrumental in nature, and result in debilitating outcomes for women and their newborn. Taking the stock of information generated by the third round of District Level Health and Facility Survey (DLHS-3) this paper adopts the Pena Distance Method to gauge the spatial variations. The states are classified first in terms of their MCH status in 2007–2008. At later stage intrastate disparities are captured by measuring rural–urban inequality, and inter-district disparity within states. Key results indicate that the overall state ranking is, to a significant extent, explained by the intrastate variations. However, the major contribution of this paper lies in quantifying the relative role of constituent indicators that are responsible for the existing disparities across and within state boundaries.

Northeast India: An important region with a rich biodiversity of Rotifera

Abstract: This study extends our previous work to investigate the planktonic rotifers of floodplain lakes (locally called as beels or pats) of Northeast India (NEI) and reviews the known rotifer diversity from the seven states of this region To do this we examined plankton samples from numerous sites from different states, including 30 floodplain lakes (beels) of Assam and 15 floodplain lakes (pats) of Manipur This survey yielded 238 species, making the region of NEI one of the most specious and diverse (50 genera and 23 families) of the Indian subcontinent Occurrence of four Australian and Asian, 10 Oriental, 13 Paleotropical, two Holarctic, two Indian pandemics, 12 Eastern Hemisphere elements, and several species of regional distribution importance are distinctive features of this rotifer assemblage The beels or pats of NEI are Rotifera rich habitats with Deepor Beel and Loktak Lake (two Ramsar sites) as globally important wetlands, and Assam (>500% of the Indian species) recorded highest richness amongst all states of this country While explaining some 63–74% of the variation of the rotifer assemblage along two axes, Canonical Correspondence Analysis yielded little insight regarding the influence of individual abiotic parameters on their diversity This study from Northeast India, a part of the Himalayan and Indo-Myanmar “hotspots,” is of special biodiversity interest