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1.
Mol Biol Rep ; 49(11): 11177-11186, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36097126

RESUMEN

BACKGROUND: Populations exhibit signatures of local adaptive traits due to spatial and environmental heterogeneity resulting in microevolution. The blue sheep is widely distributed across the high Asian mountains and are the snow leopard's principal prey species. These mountains differ in their evolutionary history due to differential glaciation and deglaciation periods, orography, and rainfall patterns, and such factors causes diversification in species. METHODS AND RESULTS: Therefore, we assess the phylogeographic status of blue sheep using the mitochondrial cytochrome b gene (220 bp) across the Indian Himalayan region (IHR) and its relationship with other populations. Of the observed five haplotypes, two and three were from the western Himalayas (WH) and eastern Himalayas (EH) respectively. One of the haplotypes from WH was shared with the population of Pamir plateau, suggesting historical maternal connectivity between these areas. The phylogenetic analyses split the blue sheep into two paraphyletic clades, and western and eastern populations of IHR were within the Pamir and Tibetan plateau clades, respectively. We observed a relatively higher mean sequence divergence in the EH population than in the WH. CONCLUSION: We propose five 'Evolutionary Significant Units' across the blue sheep distribution range based on observed variation in the species' ecological requirements, orography, climatic conditions, and maternal lineages, viz.; Western Himalaya-Pamir plateau (WHPP); Eastern Himalaya-Tibetan plateau (EHTP); Qilian mountains; Helan mountains and Hengduan mountains population. Despite the small sample size, population divergence was observed across the IHR, therefore, we suggest a transboundary, collaborative study on comparative morphology, anatomy, ecology, behaviour, and population genetics using harmonized different genetic markers for identifying the overall taxonomic status of the blue sheep across its range for planning effective conservation strategies.


Asunto(s)
Citocromos b , Genética de Población , Mitocondrias , Animales , Citocromos b/genética , Haplotipos/genética , Filogenia , Filogeografía , Ovinos/genética , Mitocondrias/metabolismo
2.
Mol Biol Rep ; 48(6): 5151-5160, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34213708

RESUMEN

The Indian antelope or blackbuck (Antilope cervicapra) is endemic to the Indian subcontinent, inhabiting scrublands and dry grasslands. Most of the blackbuck populations are small, isolated, and threatened by habitat fragmentation and degradation. Management of such disjunct populations requires genetic characterization, which is critical for assessing hazards of stochastic events and inbreeding. Addressing the scarcity of such information on the blackbuck, we describe a novel panel of microsatellite markers that could be used to monitor blackbuck demography and population genetic parameters using non-invasive faecal sampling. We screened microsatellites (n = 40) that had been reported to amplify in bovid and cervid species using faecal samples of the blackbuck collected from Kaimoor Wildlife Sanctuary, Uttar Pradesh, India and its vicinities. We selected 12 markers for amplification using faecal DNA extracts (n = 140) in three multiplex reactions. We observed a mean amplification success rate of 72.4% across loci (92.1-25.7%) with high allele diversity (mean number of alleles/locus = 8.67 ± 1.03). Mean genotyping error rates across the markers were low to moderate (allelic drop-out rate = 0.09; false allele rate = 0.11). The proportions of first- and second-order relatives in the study population were 0.69% and 6.21%, respectively. Based on amplification success, genotyping error rates and the probability of identity (PID), we suggest (i) a panel of five microsatellite markers (cumulative PID = 1.24 × 10-5) for individual identification and population monitoring and (ii) seven additional markers for conservation genetics studies. This study provides essential tools capable of augmenting blackbuck conservation strategies at the landscape level, integral to protecting the scrubland-grassland ecosystem.


Asunto(s)
Antílopes/genética , Repeticiones de Microsatélite/genética , Vigilancia de la Población/métodos , Animales , Conservación de los Recursos Naturales/métodos , Ecosistema , Heces , Genética de Población/métodos , India , Técnicas de Amplificación de Ácido Nucleico/métodos
3.
Int J Inf Manage ; 55: 102171, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32836633

RESUMEN

The Covid-19 pandemic has led to an inevitable surge in the use of digital technologies due to the social distancing norms and nationwide lockdowns. People and organizations all over the world have had to adjust to new ways of work and life. We explore possible scenarios of the digital surge and the research issues that arise. An increase in digitalization is leading firms and educational institutions to shift to work-from-home (WFH). Blockchain technology will become important and will entail research on design and regulations. Gig workers and the gig economy is likely to increase in scale, raising questions of work allocation, collaboration, motivation, and aspects of work overload and presenteeism. Workplace monitoring and technostress issues will become prominent with an increase in digital presence. Online fraud is likely to grow, along with research on managing security. The regulation of the internet, a key resource, will be crucial post-pandemic. Research may address the consequences and causes of the digital divide. Further, the issues of net neutrality and zero-rating plans will merit scrutiny. A key research issue will also be the impact and consequences of internet shutdowns, frequently resorted to by countries. Digital money, too, assumes importance in crisis situations and research will address their adoption, consequences, and mode. Aspects of surveillance and privacy gain importance with increased digital usage.

4.
Comput Methods Appl Mech Eng ; 314: 71-84, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-28090125

RESUMEN

A multi-physics model has been developed to investigate the effects of cellular level mechanisms on the thermomechanical response of ultrasonically activated soft tissue. Cellular level cavitation effects have been incorporated in the tissue level continuum model to accurately determine the thermodynamic states such as temperature and pressure. A viscoelastic material model is assumed for the macromechanical response of the tissue. The cavitation model based equation-of-state provides the additional pressure arising from evaporation of intracellular and cellular water by absorbing heat due to structural and viscoelastic heating in the tissue, and temperature to the continuum level thermomechanical model. The thermomechanical response of soft tissue is studied for the operational range of frequencies of oscillations and applied loads for typical ultrasonically activated surgical instruments. The model is shown to capture characteristics of ultrasonically activated soft tissue deformation and temperature evolution. At the cellular level, evaporation of water below the boiling temperature under ambient conditions is indicative of protein denaturation around the temperature threshold for coagulation of tissues. Further, with increasing operating frequency (or loading), the temperature rises faster leading to rapid evaporation of tissue cavity water, which may lead to accelerated protein denaturation and coagulation.

5.
Zool Stud ; 58: e19, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31966320

RESUMEN

Sex identification of individuals is an important task in wildlife forensics as well as in conservation biology. It helps scientists understand population sex ratios with respect to maintaining genetic diversity, managing inbreeding depression and preventing the demographic consequences of sex-biased poaching. The literature on the use of mammalian molecular sex markers indicates that the success of accurate sex identification is variable across species. Very little is known about the effectiveness of such markers on the mammals of South and Southeast Asia. Therefore, we selected and tested three sets of universal primers for low-cost gel-based sex identification of mammals. We amplified different sets of markers-SRY (157 bp) and 12S rRNA (384 bp); Y-53-SRY (225 bp) and ZFX/ZFY (P1/P2; 445); SRY (157 bp) and 12S rRNA (151 bp)-to be used with different types (tissue, hair and skin) of samples from 20 mammalian species. All three sets of primers amplified the sex-specific fragment in a range of samples from hair to tissue. With an increasing number of field studies using non-invasively collected samples, this proposed low-cost gel- based method of molecular sexing may be applied in various aspects of the ecology and biology of South and Southeast Asian mammals, their conservation and forensics. We suggest that at least two sets of primers be used for any biological samples to avoid ambiguity.

6.
Mitochondrial DNA A DNA Mapp Seq Anal ; 29(2): 256-265, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28117612

RESUMEN

Phylogeography and evolutionary history of the freshwater species are poorly known. We document the phylogeography of widely distributed Puntius sophore using cytochrome oxidase subunit I (COI) gene of 650 bp. In the present study, we used 61 individual sequences from known geographic locations across India whereas data are lacking from other parts of its distribution range. Total 20 haplotypes with the intra-species sequence divergence ranging from 0.004 to 0.025 were observed and they were split into two major clades (North and Northeastern to Central India). Two distant geographic (North and Northeastern to Central India) regions shared haplotype suggesting ancient river connectivity or introduction of species from Northeast and Central India. Overall nucleotide and haplotype diversities were 0.00971 and 0.915. The Tajima's D and Fu's Fs values were found negative but non-significant thus rejecting the population expansion model followed by the multimodal mode of mismatch distribution. Bayesian skyline plots from both the clade showed steady population history over time; and start of decline in recent years in the clade B (∼1000-1500 years). The present finding is in support to the 'Satpura hypothesis' proposed to explain species movement patterns from Southeast Asian countries to Indian subcontinent, seconded by P. sophore showing high genetic diversity within Northern India clade (high genetic splits) because of presence of high river network in comparison to other parts of the country.


Asunto(s)
Cyprinidae/clasificación , Complejo IV de Transporte de Electrones/genética , Análisis de Secuencia de ADN/métodos , Animales , Teorema de Bayes , Cyprinidae/genética , Proteínas de Peces/genética , Agua Dulce , Variación Genética , Haplotipos , India , Filogenia , Filogeografía , Dinámica Poblacional
7.
Mitochondrial DNA B Resour ; 3(1): 245-249, 2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33474132

RESUMEN

Genetic analysis is an important tool in understanding population structure, genetic diversity, and phylogenetics of endangered species likely to be affected by microevolution and anthropogenic factors. Western Ghats landscape is one of the identified biodiversity hotspots in India, and micro-evolutionary processes are observed in this landscape due to the presence of the gaps in the mountain ranges. Nilgiri tahr is endemic to and distributed in this landscape while very little is known about genetic characteristics, population structure and impact of these gaps on the species. In the present study, two different populations of Nilgiri tahr from the north (NPG) and south (SPG) of Palghat gap (PG) were studied using the cytochrome b gene (Cyt b; 310 bp) of mtDNA genome in the Western Ghats, India. Two variable sites were observed in the Cyt b fragment while the mean pairwise genetic distance between these two populations was 0.007. All the samples phylogenetically clustered in either north or south of PG. The presence of shallow divergence indicates the presence of suitable habitat in past which may have facilitated movement between NPG and SPG. A subsequent change in Paleo-climatic conditions and gradual formation of PG may have resulted in population diversification during the Pleistocene. Besides, Forensically Informative Nucleotide Sequence (FINS) observed would help in geo-assigning any individual from NPG or SPG to understand the likely influences on population demography due to poaching.

11.
Neurol India ; 54(3): 291-2, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16936392

RESUMEN

We describe our experience with the previously described technique of preservation of the bone flap in a subgaleal pocket created over the intact side of the calvaria, discuss our experience of this method and review the literature to compare this method with other alternative techniques.


Asunto(s)
Craneotomía/métodos , Descompresión Quirúrgica/métodos , Cráneo/cirugía , Colgajos Quirúrgicos , Conservación de Tejido/métodos , Encefalopatías/cirugía , Femenino , Humanos , Masculino , Reimplantación , Literatura de Revisión como Asunto
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