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1.
Serum samples of goats experiencing natural and experimental infections and/or reactivation of caprine herpesvirus 1 (CpHV.1) were analysed with neutralization and Western blotting (WB) tests. WB immunological patterns resulted differently and related to neutralizing titers. In serum samples having neutralizing titer 1:2-1:4, antibodies to two proteins of Mw of 150 and 34 kDa were present. Antibodies against several proteins, two of those being characterized by monoclonal antibodies as gB and gC, were visualized by WB in sera having titer > or = 1:8. The neutralizing antibody titers and the pattern of antibody reactivity were hypothesized to modulate the reactivation and re-excretion process of CpHV.1.  相似文献   

2.
Proteomics research has developed until recently in a relative isolation from other fast-moving disciplines such as ecology and evolution. This is unfortunate since applying proteomics to these disciplines has apparently the potential to open new perspectives. The huge majority of species indeed exhibit over their entire geographic range a metapopulation structure, occupying habitats that are fragmented and heterogeneous in space and/or through time. Traditionally, population genetics is the main tool used to studying metatopulations, as it describes the spatial structure of populations and the level of gene flow between them. In this Viewpoint, we present the reasons why we think that proteomics, because of the level of integration it promotes, has the potential to resolve interesting issues specific to metapopulation biology and adaptive processes.  相似文献   

3.
The paper deals with the spatial and the temporal variability of the population dynamics of five key molluscan species at two rocky intertidal shores on the southern Saurashtra coastline of India. The intertidal belts of the two selected stations, Veraval and Diu, are about 100 km apart and differ in their coast characteristics and level of human interference. The slope and the substrate types of the two stations are not uniform and the exposure of intertidal belt of these predominantly rocky shores during low tides is also not significantly long. The study revealed that a general, species specific pattern of spatial and temporal variations existed in the population abundance and density of the species studied. There was considerable spatial variability in some species examined but most species showed no clear seasonal trends for the population abundance. The Veraval coast, in spite of being affected by heavy human interference, is still a favourable place for Chiton, Turbo cornatus and Turbo intercoastalis than Diu, though the latter is relatively less affected by anthropogenic influences. It appears that the subtratum type, short exposure duration and moderate wave action of the Arabian Sea are most active controlling factors for higher distribution of these species at Veraval.  相似文献   

4.
We present the plant macroremains from the site of Vadnagar, an important centre of Buddhist learning in western India spanned between first century BCE and fourth century CE. The cultural relics and AMS dates of the recovered carbonized seeds from the cultural horizon also confirm the archaeological context. The study indicate that the likely staples were cereals (Oryza sativa, Hordeum vulgare, Triticum aestivum), leguminous crops (Vigna unguiculata, Vigna radiata, Vigna mungo, and Macrotyloma uniflorum), and oil and fibre-yielding (Linum usitatissimum and Gossypium sp.) crops. In addition, there is an evidence that fruits such as Tamarindus indica and Ziziphus sp. may have been consumed by the settlers. Few weeds and wild taxa (Paspalum scrobiculatum, Vicia sp., and Ipomoea sp.), which turned up as an admixture with the above economically important seeds/grains have also been encountered. Abundance of Oryza sativa (rice) grains and spikelet bases indicate crop-processing at the site and played significant role in the subsistence economy. Moreover, the overall assemblage of summer and winter crops suggests the prevalence of multi-cropping system attributed to conducive environmental conditions during ~100 BCE–400 CE.  相似文献   

5.
Western Ghats of Karnataka, an important biodiversity hot spot in the world, rich in insect fauna including termites. Diversity of termites from this region poorly understood. In the present study, we have redescribed 12 species and termites belonging to two families viz., Rhinotermitidae and termitidae based on morphological and molecular differences employing mitochondrial 16s rRNA. Further we have employed Bayesian inference in order to understand phylogenetic relationships among different termite species studied. The integrative taxonomic approach was successful in delimiting the species studied in the present investigation.  相似文献   

6.
Summary A theory for determining optimum planting and breeding zones is described. The theory is based on a model consisting of Gaussian response functions for traits that vary in a gradient for a single environmental variable. Environments are assumed to be normally distributed with known mean and variance. Methods are presented for determining parameters of response functions that maximize the expected value for such a trait when two, three and four populations are selected for breeding or as sources of propagules. Expected value is maximized only when the populations selected have response functions symmetrically arrayed about the mean of the environmental variable. Maximum expected value was shown to increase with increasing number of selected populations at a rate that depends upon the ratio of homostasis to environmental variability. The methods presented are illustrated with data on performance of Scots pine provenances in Sweden.Paper No. 11750 of the Journal Series of the North Carolina Agricultural Research Service, Raleigh, NC 27695-7601  相似文献   

7.
Evidence is provided of seasonal changes in the rate of DNA fragmentation dynamics of sperm collected from goats Murciano-Granadina breed), in a Spanish Breeding Centre at 41°N latitude. Results show that the initial assessment of sperm DNA fragmentation (T0) was not sufficient to differentiate sperm DNA fragmentation of bucks collected at different times of the year (Kruskal–Wallis 2.399; P = 0.493). However, when thawed semen was subsequently incubated at 37 °C for periods of between 2 and 48 h, differences were recorded in the rate of sperm DNA fragmentation (r-SDF), that are indicative of seasonal changes in reproduction (Log Rank: Mantel–Cox; χ2 = 158.6; DF = 3; P < 0.001). Goat semen collected and cryopreserved in the Spanish winter and spring resulted in a poor post-thaw sperm DNA longevity and recorded a r-SDF of 0.8 and 1.3 per hour, after 48 h of incubation respectively. The r-SDF subsequently decreased to 0.16 and 0.36 per hour during summer and autumn. It is therefore, recommended that semen samples from Murciano-Granadina goats housed above the 40°N latitude be collected and cryopreserved in the summer and early autumn. This would result in a more stable DNA molecule, which is likely to improve the reproductive success.  相似文献   

8.
Life history variations among 27 populations of the grasshopper Chorthippus brunneus from around the British Isles were examined under laboratory conditions over three generations. Multiple-regression analysis was used to examine the relationship between grasshopper life histories and the climates of their ancestral sites. Grasshoppers from cooler sites were heavier at hatching. Grasshoppers from northern sites grew faster and developed through fewer instars, attaining adulthood earlier, at the expense of adult size. Depending on the measure of adult size used, adults were larger in warmer, sunnier or more southerly locations. Ecotypic differentiation is probably widespread among animals as it is among plants, though it is more rarely demonstrated by zoological studies, especially over the wide geographical scale covered here. Evidence from regression analysis supports the hypothesis that ecotypic differentiation in C. brunneus is an evolutionary response to climatic variation. The existence of intraspecific genetic diversity for climatic adaptations has implications for biodiversity conservation and the understanding of biotic responses to climatic change. It deserves wider recognition. Received: 5 October 1998 / Accepted: 30 June 1999  相似文献   

9.
山羊精子结合外源DNA能力的年龄及品种依赖性   总被引:13,自引:0,他引:13  
本文应用正交设计L16(44),优化精子和外源DNA处理条件;用建立的方法转染1-4岁川东白山羊和波南F1公羊、2岁波尔山羊和南江黄羊公羊共149只,用原位杂交法检测精子结合外源DNA的效率,比较不同品种、年龄的山羊(Capra hircus)精子结合外源DNA的能力。结果显示川东白山羊1岁时的阳性精子率为39.34%±13.76%,4岁时降为23.40%±19.37%,与1岁和2岁时相比,差异显著;南江黄羊的阳性精子率最高,波尔山羊最低;并筛选到一种山羊精子和外源DNA处理方法。表明实验山羊的精子结合外源DNA的能力有随着年龄的增长而减少的趋势,并表现出品种间差异。  相似文献   

10.
Abstract

Jurassic deposits of shallow to marginal marine (delta) environments are widely reported from different continents of the world. This study shows inter-relationship of the animal-sediment behaviours in shallow and marginal marine conditions, suggesting an interpretation of the possible ichnodisparity. The Jurassic succession exposed at Washtawa Dome and Adhoi Anticline of Wagad highland, Kachchh comprises an approximately 341 m thick succession, divided into two formations – Lower Washtawa and Upper Wagad Sandstone. Eight sparsely to highly bioturbated sedimentary units show twenty-three identifiable ichnospecies from fifteen ichnogenera representing five ichnoassemblages broadly attributable to the Skolithos and the Cruziana ichnofacies, and developed in shallow-marine strandplain shoreface and delta depositional facies. The relative frequency statistical data reveals the dominant occurrence of feeding structures generated by polychaetes preferentially in quartz arenites. These structures represent sub-horizontal, sub-vertical and complex burrows, and show twelve and six categories of architectural designing Callovian-Oxfordian of shallow-marine shoreface and Oxfordian-Kimmeridgian shallow-water delta successions, respectively. The lower ichnodiversity and ichnodisparity associated with the Oxfordian-Kimmeridgian deltaic intervals represents a decrease in the exploitation of under-used ecospace, due to unfavourable environmental conditions rather than an expression of evolutionary radiation.  相似文献   

11.
The monitoring of airborne pollen and fungal spores ofLucknow has been achieved using a Rotorod Sampler. 43types of pollen and 40 types of fungal spores havebeen recorded over a period of one year(January–December, 1997). Pollen and fungal sporecalendars have been constructed. Quantification of theaerospora will help in further understanding aeroallergens and the diagnosis and treatment ofvarious respiratory diseases.  相似文献   

12.
13.
BackgroundIn India, more than half of the total cancer cases are diagnosed at an advanced stage resulting in a high mortality rate. Early diagnosis and proper treatment may result in reduced mortality. Understanding the treatment trajectory followed by a patient is important for reducing diagnostic delay which may result in improved prognosis and treatment. With this background, the current study attempts to understand the treatment-seeking processes of Tobacco-related Cancer (TRC) patients in the state of Assam.MethodsExplanatory Sequential Mixed design was adopted for the study. In the first phase of the study, 100 participants were interviewed using an interview schedule and then 11 in-depth interviews were conducted in the later phase to understand the subject matter in more depth.ResultsThe study revealed that the initial point of contact for seeking help for most of the participants was their family, which was followed by an alternative system of medicine including faith healers and quacks. Participants with a lower level of literacy and economic instability were seen to have approached family members, faith healers and quacks more as compared to the people with a higher level of literacy and economic stability who approached health professionals, friends, and others for initial help-seeking. Also, an association between causal health beliefs and treatment choices of the patients were discovered.ConclusionsThe study suggests addressing the beliefs and practices associated with cancer care (both modern and traditional) by engaging mass awareness. Need for designing cancer-education programmes for the general population was also advocated.  相似文献   

14.
Data are presented on group size, composition, and reproductive rates of nine free-ranging rhesus monkey groups inhabiting different habitats in India, based on 7,300 observation hours spread over 1975–1980. Analysis suggests that groups increased in size irrespective of the habitat occupied.  相似文献   

15.
正Dear Editor,The Poxviridae family is divided into Chordopoxvirinae and Entomopoxvirinae genera.Parapoxvirus is one of 11genera in the Chordopoxvirinae genus,including orf virus(ORFV),bovine papular stomatitis virus(BPSV),pseudocowpox virus(PCPV)and parapoxvirus of red deer in New Zealand(PVNZ)(Skinner et al.,2012).This virus,also known as contagious ecthyma or contagious pustular dermatitis,is a viral skin disease causing edematous proliferative lesions,most often in hairless skin  相似文献   

16.
Parapoynx stagnalis (Zeller) (=Nymphula depunctalis (Guenée), is a sporadic rice paddy pest of south and southeast Asian rice paddy fields, and widely known as rice caseworm. A recent outbreak of the pest was observed in the upland rice paddy agro-ecosystem of the central Western Ghats, India. No potential natural enemies of this pest have so far been reported, mainly due to the semi-aquatic behavior of the larvae and pupae. However, an undescribed aquatic ichneumonid wasp species (belonging to a genus near Litochila) is reported as a potentially useful early stage pupal parasitoid of this pest in our study. The host searching behavior and potential of the parasitoid wasp was studied in detail using both field and laboratory experiments. The adult female wasps usually dive into the water in search of the host pupae, remaining under water for a maximum of 90.2s, while searching for rice caseworm pupae. In field and laboratory experiments, we found 73% of the parasitized pupae of P. stagnalis kept under water yielded adult parasitic wasps. However, no parasitoids emerged from parasitized host pupae maintained in dry terrariums. Sex ratio was 2.8:1. The present discovery of the semi-aquatic parasitoid wasp could aid in better management of the rice caseworm population in rice paddy fields.  相似文献   

17.
India, which has long suffered from undernutrition, has seen a rapid rise in overweight incidence in the last decade and a half. These changes are characterized by significant within-country differences in overweight incidence that vary by gender and regional development levels. In this paper, we provide an integrative framework, linking the income-gradient hypothesis of obesity with biological, obesogenic, and environmental factors to provide an explanation on the emergence of within-country differences in overweight patterns. We utilize measured body mass index (BMI), along with individual- and household-level data of over 800,000 men and women surveyed in the National Family Health Surveys of 2005–06 and 2015–16 to identify correlates of within-country differences in overweight incidence. A decomposition analysis reveals that among women, in addition to increasing access to obesogenic technologies, biological factors are associated with overweight incidence. Among men, obesogenic factors related to technology use and health behaviors are associated with the rise in overweight incidence, but biological factors are not. At lower levels of regional development, overweight incidence is associated with greater access to obesogenic technology such as motorized transport, which reduces physical activity among men at higher rates than women. At higher levels of economic development, obesogenic behaviors, such as watching more television and reducing smoking, are associated with overweight incidence. Our results corroborate the call by public health experts for group-specific policies to stem the rise of overweight incidence in developing countries.  相似文献   

18.
We used camera trapping in conjunction with a spatial explicit capture–recapture model to estimate striped hyena (Hyaena hyaena) density and occupancy models to investigate factors affecting striped hyena detection probabilities in Ranthambhore Tiger Reserve (RTR), Rajasthan, India. A sampling effort of 4,450 trap days/nights over 75 days yield 68 photo captures of 21 unique striped hyenas (based on individual markings and visual identification); the estimated striped hyena density was 5.49?±?1.27 individuals/100 km2. Results of our occupancy model suggested that a rugged terrain is an important factor that influences striped hyena detection probability. Correlation with striped hyena detection with human settlement provides evidence of social tolerance of striped hyena towards humans, and more occurrence of resources allowed coexistence of hyena in a human-dominated landscape. This elasticity (inhabited areas close to humans) demonstrated by striped hyenas is an exception among carnivore communities living in this semi-arid habitat.  相似文献   

19.
We record here the occurrence of five exotic fish species viz Oreochromis mossambicus, Gambusia affinis, Osphronemus goramy, Xiphophorus maculatus and Poecilia reticulata in the Chalakudy River, part of the Western Ghats, a global biodiversity hotspot in Kerala, India. O. mossambicus was ubiquitous in occurrence with large shoals being encountered at all sampling sites spread along the downstream-upstream gradient of the river, including at an altitude of 1050 m ASL. Osphronemus goramy was recorded from the downstream region of the river while Gambusia affinis was recorded from three sampling sites located downstream as well as midstream. Xiphophorus maculatus was collected from a second order stream flowing through a tea plantation at an altitude of 1050 m ASL. Samples of brooders and early fry of Poecilia reticulata indicate that the fish has already established a breeding population in the river. Possible threats to the indigenous fish fauna of the Chalakudy River as a result of the invasion and proliferation of these exotics is discussed.  相似文献   

20.
Experimental research has identified many putative agents of amphibian decline, yet the population-level consequences of these agents remain unknown, owing to lack of information on compensatory density dependence in natural populations. Here, we investigate the relative importance of intrinsic (density-dependent) and extrinsic (climatic) factors impacting the dynamics of a tree frog (Hyla arborea) population over 22 years. A combination of log-linear density dependence and rainfall (with a 2-year time lag corresponding to development time) explain 75% of the variance in the rate of increase. Such fluctuations around a variable return point might be responsible for the seemingly erratic demography and disequilibrium dynamics of many amphibian populations.  相似文献   

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