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There are 15 species of Anostraca belonging to 6 genera on the Indian Subcontinent. These are:Artemia sp. (reportedly a bisexual form of undetermined species);Artemia parthenogenetica Bowen & Sterling, 1978;Branchinecta orientalis Sars, 1901;Branchinella hardingi (Qadri & Baqai, 1956);Branchinella kugenumaensis (Ishikawa, 1895);Branchinella ornata Daday, 1910;Branchipodopsis acanthopenes (Malhotra & Duda, 1970);Branchipodopsis affinis Sars, 1901;Branchipus schaefferi Fischer, 1834;Chirocephalus priscus (Daday, 1910);Streptocephalus dichotomus Baird, 1860;Streptocephalus echinus Bond, 1934;Streptocephalus longimanus Bond, 1934;Streptocephalus simplex Gurney, 1906;Streptocephalus spinifer Gurney, 1906.Comparing numbers of species for southern India with other reasonably well studied areas, demonstrated that anostracan species richness is higher in the climatically more varied temperate regions than it is in the more uniform tropics. Tropical South India has six species compared to 13 in Arizona (USA), 19 in California (USA), 10 in Morocco, and 14 in Italy. 相似文献
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Anette Stauch Hans-Peter Duerr Albert Picado Bart Ostyn Shyam Sundar Suman Rijal Marleen Boelaert Jean-Claude Dujardin Martin Eichner 《PLoS neglected tropical diseases》2014,8(4)
The elimination of infectious diseases requires reducing transmission below a certain threshold. The Visceral Leishmaniasis (VL) Elimination Initiative in Southeast Asia aims to reduce the annual VL incidence rate below 1 case per 10,000 inhabitants in endemic areas by 2015 via a combination of case management and vector control. Using a previously developed VL transmission model, we investigated transmission thresholds dependent on measures reducing the sand fly density either by killing sand flies (e.g., indoor residual spraying and long-lasting insecticidal nets) or by destroying breeding sites (e.g., environmental management).Model simulations suggest that elimination of VL is possible if the sand fly density can be reduced by 67% through killing sand flies, or if the number of breeding sites can be reduced by more than 79% through measures of environmental management.These results were compared to data from two recent cluster randomised controlled trials conducted in India, Nepal and Bangladesh showing a 72% reduction in sand fly density after indoor residual spraying, a 44% and 25% reduction through the use of long-lasting insecticidal nets and a 42% reduction after environmental management.Based on model predictions, we identified the parameters within the transmission cycle of VL that predominantly determine the prospects of intervention success. We suggest further research to refine model-based predictions into the elimination of VL. 相似文献
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Filip Meheus Manica Balasegaram Piero Olliaro Shyam Sundar Suman Rijal Md. Abul Faiz Marleen Boelaert 《PLoS neglected tropical diseases》2010,4(9)
Background
Visceral leishmaniasis is a systemic parasitic disease that is fatal unless treated. We assessed the cost and cost-effectiveness of alternative strategies for the treatment of visceral leishmaniasis in the Indian subcontinent. In particular we examined whether combination therapies are a cost-effective alternative compared to monotherapies.Methods and Findings
We assessed the cost-effectiveness of all possible mono- and combination therapies for the treatment of visceral leishmaniasis in the Indian subcontinent (India, Nepal and Bangladesh) from a societal perspective using a decision analytical model based on a decision tree. Primary data collected in each country was combined with data from the literature and an expert poll (Delphi method). The cost per patient treated and average and incremental cost-effectiveness ratios expressed as cost per death averted were calculated. Extensive sensitivity analysis was done to evaluate the robustness of our estimations and conclusions. With a cost of US$92 per death averted, the combination miltefosine-paromomycin was the most cost-effective treatment strategy. The next best alternative was a combination of liposomal amphotericin B with paromomycin with an incremental cost-effectiveness of $652 per death averted. All other strategies were dominated with the exception of a single dose of 10mg per kg of liposomal amphotericin B. While strategies based on liposomal amphotericin B (AmBisome) were found to be the most effective, its current drug cost of US$20 per vial resulted in a higher average cost-effectiveness. Sensitivity analysis showed the conclusion to be robust to variations in the input parameters over their plausible range.Conclusions
Combination treatments are a cost-effective alternative to current monotherapy for VL. Given their expected impact on the emergence of drug resistance, a switch to combination therapy should be considered once final results from clinical trials are available. 相似文献5.
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The origin of whales (order Cetacea) from a four-footed land animal is one of the best understood examples of macroevolutionary
change. This evolutionary transition has been substantially elucidated by fossil finds from the Indian subcontinent in the
past decade and a half. Here, we review the first steps of whale evolution, i.e. the transition from a land mammal to obligate
marine predators, documented by the Eocene cetacean families of the Indian subcontinent: Pakicetidae, Ambulocetidae, Remingtonocetidae,
Protocetidae, and Basilosauridae, as well as their artiodactyl sister group, the Raoellidae. We also discuss the influence
that the excellent fossil record has on the study of the evolution of organ systems, in particular the locomotor and hearing
systems. 相似文献
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DIETER AMMERMANN GULSHAN R. SAPRA MARTIN SCHLEGEL 《The Journal of eukaryotic microbiology》1987,34(1):31-34
A new species, Pleurotricha indica n. sp., is described, characterized by an average size of 220 × 119 μm, a firm and inflexible body, six rows of dorsal kineties, one left and two right rows of marginal cirri, and an “Oxytricha-like” pattern of ventral cirri. The parts of the macronucleus are variable in shape and number. The comparison with other members of the genus shows that P. indica differs from other congeneric species in the combination of these characters. 相似文献
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Parallel clines for starvation resistance and lipid content are well documented among drosophilids on the Indian subcontinent. However, the mechanistic basis of these clines has not been investigated so far. Here, we investigate the utilization of lipids during starvation as a function of duration of stress in D. ananassae. We found higher lipid content responsible for high starvation resistance at lower latitudes. Lipids were utilized during starvation only; not during any other climatic stresses like desiccation or thermal stresses. We also found a cline for consumption of total body lipids; as more content (out of total amount of lipids) was utilized by flies at lower latitudes and lesser at higher latitudes. But, there was no latitudinal cline for threshold lipid amount in the case of females while for males there was a positive cline. Lastly, parallel clines have evolved under contrasting climatic conditions i.e. drier and colder northern localities have flies with lower lipid and reduced starvation resistance while hot and humid localities favor flies with higher lipid levels and greater starvation tolerance. Thus, the evolution of clines associated with starvation and lipid content might have resulted due to specific ecological conditions i.e. humidity gradient on the Indian subcontinent. 相似文献
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Large numbers of the Globe Skimmer dragonfly (Pantala flavescens) appear in the Maldives every October–December. Since they cannot breed on these largely waterless islands, it has recently been suggested that they are “falling out” during a trans-oceanic flight from India to East Africa. In addition, it has been suggested that this trans-oceanic crossing is just one leg of a multi-generational migratory circuit covering about 14,000–18,000 km. The dragonflies are presumed to accomplish this remarkable feat by riding high-altitude winds associated with the Inter-tropical Convergence Zone (ITCZ). While there is considerable evidence for this migratory circuit, much of that evidence is circumstantial. Recent developments in the application of stable isotope analyses to track migratory dragonflies include the establishment of direct associations between dragonfly wing chitin δ
2H values with those derived from long-term δ
2H precipitation isoscapes. We applied this approach by measuring wing chitin δ
2H values in 49 individual Pantala flavescens from the November–December migration through the Maldives. Using a previously established spatial calibration algorithm for dragonflies, the mean wing δ
2H value of −117±16 ‰ corresponded to a predicted mean natal ambient water source of −81 ‰, which resulted in a probabilistic origin of northern India, and possibly further north and east. This strongly suggests that the migratory circuit of this species in this region is longer than previously suspected, and could possibly involve a remarkable trans-Himalayan high-altitude traverse. 相似文献
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BackgroundVisceral leishmaniasis (VL) is a disease caused by two known vector-borne parasite species (Leishmania donovani, L. infantum), transmitted to man by phlebotomine sand flies (species: Phlebotomus and Lutzomyia), resulting in ≈50,000 human fatalities annually, ≈67% occurring on the Indian subcontinent. Indoor residual spraying is the current method of sand fly control in India, but alternative means of vector control, such as the treatment of livestock with systemic insecticide-based drugs, are being evaluated. We describe an individual-based, stochastic, life-stage-structured model that represents a sand fly vector population within a village in India and simulates the effects of vector control via fipronil-based drugs orally administered to cattle, which target both blood-feeding adults and larvae that feed on host feces.ConclusionsOur model should prove useful in a priori evaluation of the efficacy of fipronil-based drugs in controlling leishmaniasis on the Indian subcontinent and beyond. 相似文献
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We extend the continuity of microblade technology in the Indian Subcontinent to 45 ka, on the basis of optical dating of microblade assemblages from the site of Mehtakheri, (22° 13'' 44″ N Lat 76° 01'' 36″ E Long) in Madhya Pradesh, India. Microblade technology in the Indian Subcontinent is continuously present from its first appearance until the Iron Age (~3 ka), making its association with modern humans undisputed. It has been suggested that microblade technology in the Indian Subcontinent was developed locally by modern humans after 35 ka. The dates reported here from Mehtakheri show this inference to be untenable and suggest alternatively that this technology arrived in the Indian Subcontinent with the earliest modern humans. It also shows that modern humans in Indian Subcontinent and SE Asia were associated with differing technologies and this calls into question the “southern dispersal” route of modern humans from Africa through India to SE Asia and then to Australia. We suggest that modern humans dispersed from Africa in two stages coinciding with the warmer interglacial conditions of MIS 5 and MIS 3. Competitive interactions between African modern humans and Indian archaics who shared an adaptation to tropical environments differed from that between modern humans and archaics like Neanderthals and Denisovans, who were adapted to temperate environments. Thus, while modern humans expanded into temperate regions during warmer climates, their expansion into tropical regions, like the Indian Subcontinent, in competition with similarly adapted populations, occurred during arid climates. Thus modern humans probably entered the Indian Subcontinent during the arid climate of MIS 4 coinciding with their disappearance from the Middle East and Northern Africa. The out of phase expansion of modern humans into tropical versus temperate regions has been one of the factors affecting the dispersal of modern humans from Africa during the period 200–40 ka. 相似文献
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T. C. Narendran 《BioControl》1984,29(4):431-438
The Indian chalcid wasps of the familyChalcididae now comprise 30 genera including 4 new records. An illustrated key to the identification of these 30 genera is provided along with relevant subfamilies and tribes. Synonyms of the genera are also provided.
Résumé Les chalicidens de l'Inde de la famille desChalcididae comprennent maintenant 30 genres incluant 4 nouveaux. Une clé dichotomique pour l'identification de ces 30 genres est présentée en mentionnant les sous-familles et les tribus. Les synonymes de ces genres sont signalés.相似文献
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Carlos A. Driscoll Nobuyuki Yamaguchi Gila Kahila Bar-Gal Alfred L. Roca Shujin Luo David W. Macdonald Stephen J. O'Brien 《PloS one》2009,4(1)
The Caspian tiger (Panthera tigris virgata) flourished in Central Asian riverine forest systems in a range disjunct from that of other tigers, but was driven to extinction in 1970 prior to a modern molecular evaluation. For over a century naturalists puzzled over the taxonomic validity, placement, and biogeographic origin of this enigmatic animal. Using ancient-DNA (aDNA) methodology, we generated composite mtDNA haplotypes from twenty wild Caspian tigers from throughout their historic range sampled from museum collections. We found that Caspian tigers carry a major mtDNA haplotype differing by only a single nucleotide from the monomorphic haplotype found across all contemporary Amur tigers (P. t. altaica). Phylogeographic analysis with extant tiger subspecies suggests that less than 10,000 years ago the Caspian/Amur tiger ancestor colonized Central Asia via the Gansu Corridor (Silk Road) from eastern China then subsequently traversed Siberia eastward to establish the Amur tiger in the Russian Far East. The conservation implications of these findings are far reaching, as the observed genetic depletion characteristic of modern Amur tigers likely reflects these founder migrations and therefore predates human influence. Also, due to their evolutionary propinquity, living Amur tigers offer an appropriate genetic source should reintroductions to the former range of the Caspian tiger be implemented. 相似文献
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Sherry R. Jacob Vandana Tyagi Anuradha Agrawal Shyamal K. Chakrabarty Rishi K. Tyagi 《PloS one》2015,10(5)
Food security is a global concern amongst scientists, researchers and policy makers. No country is self-sufficient to address food security issues independently as almost all countries are inter-dependent for availability of plant genetic resources (PGR) in their national crop improvement programmes. Consultative Group of International Agricultural Research (CGIAR; in short CG) centres play an important role in conserving and distributing PGR through their genebanks. CG genebanks assembled the germplasm through collecting missions and acquisition the same from national genebanks of other countries. Using the Genesys Global Portal on Plant Genetic Resources, the World Information and Early Warning System (WIEWS) on Plant Genetic Resources for Food and Agriculture and other relevant databases, we analysed the conservation status of Indian-origin PGR accessions (both cultivated and wild forms possessed by India) in CG genebanks and other national genebanks, including the United States Department of Agriculture (USDA) genebanks, which can be considered as an indicator of Indian contribution to the global germplasm collection. A total of 28,027,770 accessions are being conserved world-wide by 446 organizations represented in Genesys; of these, 3.78% (100,607) are Indian-origin accessions. Similarly, 62,920 Indian-origin accessions (8.73%) have been conserved in CG genebanks which are accessible to the global research community for utilization in their respective crop improvement programmes. A total of 60 genebanks including 11 CG genebanks have deposited 824,625 accessions of PGR in the Svalbard Global Seed Vault (SGSV) as safety duplicates; the average number of accessions deposited by each genebank is 13,744, and amongst them there are 66,339 Indian-origin accessions. In principle, India has contributed 4.85 times the number of germplasm accessions to SGSV, in comparison to the mean value (13,744) of any individual genebank including CG genebanks. More importantly, about 50% of the Indian-origin accessions deposited in SGSV are traditional varieties or landraces with defined traits which form the backbone of any crop gene pool. This paper is also attempting to correlate the global data on Indian-origin germplasm with the national germplasm export profile. The analysis from this paper is discussed with the perspective of possible implications in the access and benefit sharing regime of both the International Treaty on Plant Genetic Resources for Food and Agriculture and the newly enforced Nagoya Protocol under the Convention on Biological Diversity. 相似文献
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Response of the Abundance of Key Soil Microbial Nitrogen-Cycling Genes to Multi-Factorial Global Changes 总被引:1,自引:0,他引:1
Ximei Zhang Wei Liu Michael Schloter Guangming Zhang Quansheng Chen Jianhui Huang Linghao Li James J. Elser Xingguo Han 《PloS one》2013,8(10)
Multiple co-occurring environmental changes are affecting soil nitrogen cycling processes, which are mainly mediated by microbes. While it is likely that various nitrogen-cycling functional groups will respond differently to such environmental changes, very little is known about their relative responsiveness. Here we conducted four long-term experiments in a steppe ecosystem by removing plant functional groups, mowing, adding nitrogen, adding phosphorus, watering, warming, and manipulating some of their combinations. We quantified the abundance of seven nitrogen-cycling genes, including those for fixation (nifH), mineralization (chiA), nitrification (amoA of ammonia-oxidizing bacteria (AOB) or archaea (AOA)), and denitrification (nirS, nirK and nosZ). First, for each gene, we compared its sensitivities to different environmental changes and found that the abundances of various genes were sensitive to distinct and different factors. Overall, the abundances of nearly all genes were sensitive to nitrogen enrichment. In addition, the abundances of the chiA and nosZ genes were sensitive to plant functional group removal, the AOB-amoA gene abundance to phosphorus enrichment when nitrogen was added simultaneously, and the nirS and nirK gene abundances responded to watering. Second, for each single- or multi-factorial environmental change, we compared the sensitivities of the abundances of different genes and found that different environmental changes primarily affected different gene abundances. Overall, AOB-amoA gene abundance was most responsive, followed by the two denitrifying genes nosZ and nirS, while the other genes were less sensitive. These results provide, for the first time, systematic insights into how the abundance of each type of nitrogen-cycling gene and the equilibrium state of all these nitrogen-cycling gene abundances would shift under each single- or multi-factorial global change. 相似文献
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Very little is known about prey selection by the Indian tiger Panthera tigris tigris in tropical dry deciduous forests or in wild herbivore-depleted habitats with high livestock pressures. We undertook a short-term study in a large south Indian tiger reserve and examined two intensive study areas (SA's) from October 1998 – June 1999. In each area, herbivore sightings were recorded, scats were collected, and wild prey and livestock kills documented. Chital, wild boar and sambar were the most abundant among the wild herbivores in the study area. Scat analysis revealed wild boar (Sus scrofa) being the most common prey followed by chital (Axis axis) and sambar (Rusa unicolor). Livestock comprised less than 7% of diet intake. Here, the tigers consumed a lower mean prey mass (56.3 kg) than in other reserves. Our study suggests that in tropical dry deciduous forests with low natural prey density, smaller prey species, and high livestock biomass, tigers preferentially kill smaller prey and generally avoid livestock predation. 相似文献