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1.
Jerdon's Courser Rhinoptilus bitorquatus is one of the most endangered and least understood birds in the world. It is endemic to scrub habitats in southeast India which have been lost and degraded because of human land use. We used satellite images from 1991 and 2000 and two methods for classifying land cover to quantify loss of Jerdon's Courser habitat. The scrub habitats on which this species depends decreased in area by 11–15% during this short period (9.6 years), predominantly as a result of scrub clearance and conversion to agriculture. The remaining scrub patches were smaller and further from human settlements in 2000 than in 1991, implying that much of the scrub loss had occurred close to human population centres. We discuss the implications of our results for the conservation of Jerdon's Courser and the use of remote sensing methods in conservation.  相似文献   

2.
Ethnic populations of India as seen from an evolutionary perspective   总被引:5,自引:0,他引:5  
It is now widely accepted that (i) modern humans,Homo sapiens sapiens, evolved in Africa, (ii) migrated out of Africa and replaced archaic humans in other parts of the world, and (iii) one of the first waves of out-of-Africa migration came into India. India, therefore, served as a major corridor for dispersal of modern humans. By studying variation at DNA level in contemporary human populations of India, we have provided evidence that mitochondrial DNA haplotypes based on RFLPs are strikingly similar across ethnic groups of India, consistent with the hypothesis that a small number of females entered India during the initial process of the peopling of India. We have also provided evidence that there may have been dispersal of humans from India to southeast Asia. In conjunction with haplotype data, nucleotide sequence data of a hypervariable segment (HVS-1) of the mitochondrial genome indicate that the ancestors of the present austro-asiatic tribal populations may have been the most ancient inhabitants of India. Based on Y-chromosomal RFLP and STRP data, we have also been able to trace footprints of human movements from west and central Asia into India.  相似文献   

3.
Indoor residual spraying with DDT was the principle method by which malaria transmission was eradicated or greatly reduced in many countries between the late 1940s and 1970s. Since then, decreasing use of DDT has been associated with a resurgence of malaria in India, Sri Lanka, former Soviet Central Asia, Zanzibar, Venezuela and several other Latin American countries. In India and Zanzibar, DDT resistance in vectors, as well as a decline in spray coverage, are probable causes of reduced effectiveness of DDT in recent decades. In southern Europe, eradication of malaria transmission was achieved by DDT spraying in the 1940s and 50s and eradication has been sustained by adequate treatment of imported human malaria cases. In the highlands of Madagascar and South Africa, recent reversion to DDT spraying has been successful in stemming resurgences of malaria. Continued use of DDT for vector control, but not for agriculture, is approved by the Stockholm Convention on Persistent Organic Pollutants. DDE residues in breast milk have been associated with DDT anti-malaria spraying in South Africa, but it is not known whether this is harmful. A claimed association of DDE residues with breast cancer have not been substantiated. There is a recent report of association of DDE residues with probability of premature birth; the possible relevance of this to anti-malarial use of DDT should be investigated. In Colombia, testing of the DDT stockpile for suspensibility, DDT resistance in Anopheles darlingi and investigation of the present affordability of widespread spraying with DDT, compared with alternative chemicals, are recommended.  相似文献   

4.
The Mikirs living in Karbi-Anglong district in northeastern India depend on the natural plant resources of their neighbouring forests for much of their food, all their medicine, and for other material cultural needs and recreation. They, of course, use many plants in their magico-religious ceremonies. The area has remained botanically and ethnobotanically unexplored until the recent studies were initiated in 1976. Many heretofore unknown or little-known uses of plants have been recorded. However, much remains to be learnt from this region regarding the use of plants for human welfare.  相似文献   

5.
The Malwa region of Punjab, India, is facing an unprecedented crisis of environmental health linked to indiscriminate, excessive, and unsafe use of pesticides, fertilizers, and poor groundwater quality. The region has been described as India's “cancer capital” due to abnormally high number of cancer cases, which have increased 3-fold in the last 10 years. Studies of this region have also highlighted a sharp increase in many other pesticide-related diseases, such as mental retardation and reproductive disorders. The most affected individuals are the agricultural workers who are directly exposed to pesticides. The Malwa region of Punjab, India, is less than 15% of the total area of Punjab (only 0.5% of the total geographical area of India), but it consumes nearly 75% of the total pesticides used in Punjab. The high use of pesticides, along with environmental and social factors, is responsible for the high concentration of pesticide residues in the food chain of this region. Moreover, many banned and restricted pesticides are still in use in this region, warranting strict periodical health checkups and other interventions. The present review describes occupational, environmental, and social factors associated with pesticide use in the Malwa region of Punjab, India, and proposes some risk reduction interventions.  相似文献   

6.
We investigated whether sexual imprinting on an artificial novel adornment in the Javanese Mannikin Lonchura leucogastroides , a monomorphic estrildid finch, can occur and might provide a mechanism for the evolution of novel traits. We introduced a red feather on the forehead as a novel adornment. Young were raised by parents which were both adorned, which were both unadorned, or only one of which was adorned with the red feather. We tested the female and male offspring of those parents in mate choice tests with an adorned and unadorned conspecific of the opposite sex. Males raised by an adorned mother or adorned parents preferred adorned females significantly more often than males raised by unadorned parents. We conclude that males were sexually imprinted on the red feather. Females raised by an adorned mother or raised by adorned parents significantly preferred adorned males, whereas females raised by unadorned parents showed no preference for adorned males. Thus, females also became imprinted on the red feather. Males might learn the novel adornment in combination with the parent's sex or learn just the most conspicuous sex, whereas females showed a preference for the adornment independent of which sex bore the feather. Our study shows that sexual imprinting might be an effective mechanism for the evolution of a novel trait and that males and females might become imprinted on a novel trait in different ways.  相似文献   

7.
嵩山野生观赏植物研究   总被引:10,自引:1,他引:9  
在1985-1991年调查研究的基础上,筛选出嵩山野生观赏植物63科、132属、253种及变种。其中行道树、庭园树及风景林树种63种,花灌木74种,草本花卉48种,草坪及耐荫植物38种,垂直绿化植物28种,树桩盆景植物22种,切花植物25种。最后,对嵩山野生观赏植物的保护和利用,提出了建设性意见。  相似文献   

8.
Rao  R. J. 《Hydrobiologia》2001,458(1-3):159-168
The Ganga River in northern India is of great importance because its water is used for human and cattle consumption, power generation, fish production and irrigation and for pilgrimage. A total of 40 species of zooplanktons, four crustaceans, 15 molluscs, 51 insects, 83 fishes, 12 freshwater turtles, two crocodiles, 48 aquatic birds and two mammal species have been identified in the upper Ganga River. The river has been under constant threat of pollution by sewage and industrial wastes, disposal of dead bodies, deforestation, excessive use of fertilizers and pesticides, bathing, pilgrimage and water development programmes. The pollution of the river has become a matter of concern for all. Any change in aquatic environment will alter the structure and composition of the biotic community. For biological restoration in the Ganga River, the government of India has taken up an Action Plan. Several agencies for example, the Central Ganga Authority, several research establishments, government and non-government organizations have done considerable work under various projects. Local participation in various programmes has contributed much to the biological restoration in the Ganga River. This paper presents species lists and highlights the major issues for resource management in the upper Ganga River.  相似文献   

9.
Land use caused by human socioeconomic activities is a driver of change in the global environment. To understand and quantify land‐use change on Earth's natural systems, interdisciplinary approaches linking biophysical and socioeconomic parameters are required. One approach to understand the degree of terrestrial colonization of the biosphere is using the human appropriation of net primary productivity (HANPP). HANPP is defined as the difference between the net primary productivity (NPP) of potential vegetation and the actual NPP for a given area of land. Here, we use HANPP as a lens to examine land‐use change in India from 1700 to 2007 using a spatially explicit data set that extends over this period. We also used the nongridded, Food and Agriculture Organization (FAO) data set to calculate HANPP for India from 1961 to 2012 and compared our results. The average potential NPP for India was estimated to be 664 grams of carbon per square meter per year (g C/m2/year). Between 1700 and 2012, the fraction of pastureland and cropland increased from 20% to almost 60%. HANPP as a fraction of the potential NPP increased from 29% to 73% over this period. Calculations of HANPP using the FAO data set yielded an increase from 600 g C/m2 to just over 700 g C/m2 between 1961 and 2012. We also calculated the embodied HANPP of India by considering imports and exports, but the difference between the two is negligible in comparison to the HANPP of India. We further examined the variation of HANPP with socioeconomic parameters such as the Human Development Index (HDI) and population density. There was a roughly negative trend of HANPP with HDI. HANPP roughly increases with population density and then plateaus above a population density of roughly 200 persons per square kilometer.  相似文献   

10.
The henipaviruses, represented by Hendra (HeV) and Nipah (NiV) viruses are highly pathogenic zoonotic paramyxoviruses with uniquely broad host tropisms responsible for repeated outbreaks in Australia, Southeast Asia, India and Bangladesh. The high morbidity and mortality rates associated with infection and lack of licensed antiviral therapies make the henipaviruses a potential biological threat to humans and livestock. Henipavirus entry is initiated by the attachment of the G envelope glycoprotein to host cell membrane receptors. Previously, henipavirus-neutralizing human monoclonal antibodies (hmAb) have been isolated using the HeV-G glycoprotein and a human naïve antibody library. One cross-reactive and receptor-blocking hmAb (m102.4) was recently demonstrated to be an effective post-exposure therapy in two animal models of NiV and HeV infection, has been used in several people on a compassionate use basis, and is currently in development for use in humans. Here, we report the crystal structure of the complex of HeV-G with m102.3, an m102.4 derivative, and describe NiV and HeV escape mutants. This structure provides detailed insight into the mechanism of HeV and NiV neutralization by m102.4, and serves as a blueprint for further optimization of m102.4 as a therapeutic agent and for the development of entry inhibitors and vaccines.  相似文献   

11.

Background

Cystic echinococcosis (CE) caused by the Echinococcus granulosus, is a major public health problem worldwide, including India. The different genotypes of E. granulosus responsible for human hydatidosis have been reported from endemic areas throughout the world. However, the genetic characterization of E. granulosus infecting the human population in India is lacking. The aim of study was to ascertain the genotype(s) of the parasite responsible for human hydatidosis in North India.

Methodology/Principal Findings

To study the transmission patterns of E. granulosus, genotypic analysis was performed on hydatid cysts obtained from 32 cystic echinococcosis (CE) patients residing in 7 different states of North India. Mitochondrial cytochrome c oxidase subunit1 (cox1) sequencing was done for molecular identification of the isolates. Most of the CE patients (30/32) were found to be infected with hydatid cyst of either G3 (53.1%) or G1 (40.62%) genotype and one each of G5 (cattle strain) and G6 (camel strain) genotype.

Conclusions/Significance

These findings demonstrate the zoonotic potential of G1 (sheep strain) and G3 (buffalo strain) genotypes of E. granulosus as these emerged as predominant genotypes infecting the humans in India. In addition to this, the present study reports the first human CE case infected with G5 genotype (cattle strain) in an Asian country and presence of G6 genotype (camel strain) in India. The results may have important implications in the planning of control strategies for human hydatidosis.  相似文献   

12.
民族昆虫学简介   总被引:1,自引:0,他引:1  
梁宏斌  张润志 《昆虫知识》2001,38(4):314-319
民族昆虫学是研究在非工业化社会中人与昆虫关系的科学。民族昆虫学的研究内容包括 :昆虫的食用、药用、观赏 ,利用昆虫娱乐和装饰 ,有害昆虫防治 ,昆虫崇拜和关于昆虫的神化传说等。研究民族昆虫学的方法有查阅文献和实地调查 ,两种方法相互补充。中国有许多民族处于偏远封闭的环境里 ,研究和挖掘他们与昆虫的相对独特的关系 ,吸收其成功的昆虫利用或防治经验 ,对促进各民族间交流和发展具有重要意义  相似文献   

13.
The dried ripe fruits of Barbary wolfberry, Lycium barbarum L. are widely used in China for medicinal purposes and as a functional food. Previous investigations reported to have found atropine in Barbary wolfberries from India. These results have been questioned. Since then, however, there has been a discussion on whether the berries are suitable for human consumption. In order to determine the content of atropine, we have analysed eight samples of berries from China and Thailand for traces of atropine, using highly selective and sensitive HPLC-MS methods. Atropine was found in all examined samples in concentrations of maximally 19 ppb (w/w). Therefore, the content is far below toxic levels.  相似文献   

14.
Since April 2009, a serious pandemic infection has been rapidly spread across the world. These infections are caused due to the novel swine origin influenza A (H1N1) virus and hence these are commonly called as "Swine Flu". This new virus is the reassortment of avian, human and swine influenza viruses and thus it has a unique genome composition. There are 16 different types of hemagglutinin (HA) and 9 different types of neuraminidase (NA) that can be genetically and antigenetically differentiated. The first influenza A virus isolated from pigs was of the H1N1 subtype and these viruses have been reported to cause infection in pigs in many countries. The outbreak of this virus has been transmitted from pigs to humans. This new reassorted (exchange of genes) virus which is the cause of 2009 pandemic infections has the ability to spread from human to human. This spread of infection should be brought to an end. In this study, a phylogenetic analysis of the nucleotide sequences of the RNA segments of human H1N1 viruses was carried using MEGA version 4.0 to demonstrate the route map of infection to India. Phylogenetic analysis of the sequences from India, published in Influenza Virus Resource (a database that integrates information gathered from the Influenza Genome Sequencing Project of the National Institute of Allergy and Infectious diseases (NIAID) and the genbank of the (NCBI)) was retrieved and used for the analysis. The results showed that the various segments of the Indian isolates clustered well with the sequences from American, Asian and European countries and thus indicating the transmission of viruses from these places to India.  相似文献   

15.
This article engages with anthropological approaches to the study of global human rights discourses around reproductive and maternal health in India. Whether couched in the language of human rights or of other social justice frameworks, different forms of claims‐making in India exist in tandem and correspond to particular traditions of activism and struggle. Universal reproductive rights language remains a discourse aimed at the state in India, where the primary purpose is to demand greater accountability in the domain of policy and governance. Outside of these spheres, other languages are strategically chosen by activists for their greater resonance in addressing individual cases of women claiming reproductive violence within the context of the family as well as localized histories of feminist struggle and social justice. In focusing on the work of legal activists and the discourses which inform their interventions, this article seeks to understand how the language of reproductive rights is used in the context of India, not as a `Western import' which is adapted to local contexts, but rather as one of multiple frameworks of claims‐making drawn upon by legal activists emerging from distinct histories of struggle for gender equality and social justice.  相似文献   

16.
Epidemiologic studies have been effective in identifying human environmental and occupational hazards. However, most epidemiologic data has been difficult to use in quantitative risk assessments because of the vague specification of exposure and dose. Toxicologic animal studies have used applied doses (quantities administered, or exposures with fixed duration) and well characterized end points to determine effects. However, direct use of animal data in human risk assessment has been limited by uncertainties in the extrapolation. The applied dose paradigm of toxicology is not suited for cross species extrapolation, nor for use in epidemiology as a dose metric because of the complexity of human exposures. Physiologically based pharmacokinetic (PBPK) modeling can estimate the time course of tissue concentrations in humans, given an exposure-time profile, and it has been used for extrapolating findings from animals to humans. It is proposed that human PBPK modeling can be used in appropriately designed epidemiologic studies to estimate tissue concentrations. Secondly, tissue time courses can be used to form dose metrics based on the type and time course of adverse effects. These dose metrics will strengthen the determination of epidemiologic dose-response relationships by reducing misclassification. Findings from this approach can be readily integrated into quantitative risk assessment.  相似文献   

17.
Abstract

Although sorghum has been used for centuries as a food-crop in Africa and India, researchers in the United States and Europe have only relatively recently become interested in the potential of this unique cereal. Much of this interest focuses on the potential use of sorghum in food product development for individuals with allergies to foods containing wheat-based flours. Because it lacks gluten, sorghum is considered safe for people diagnosed with celiac disease, a condition marked by intolerance to gluten. Recent studies have shown that certain sorghum varieties, tan-plant sorghums, can be used to produce high-quality food and beverage products including cookies, waffles, flour, bread, noodles and beer. The intention is to promote the use and marketing of these sorghums in the Italian Campania Region for sorghum flours suitable as food for celiac patients.  相似文献   

18.
Cabbage (Brassica olearaceae var. capitata) and cauliflower (Brassica oleracea var. botrytis) are two major vegetables produced and consumed in India. Over the years, they have been cultivated more intensively. This has resulted in higher rates of pest infestation, especially by the diamondback moth (Plutella xylostella) and higher pesticide use. This, in turn, has contributed to insecticide resistance, environmental degradation, and human health impacts, which have triggered a growing interest in alternative management techniques. There is a dearth of knowledge on current pest management practices in cabbage and crucifer. Knowledge about pest management practices is necessary to develop appropriate strategies such as Integrated Pest Management. The main purpose of this study was to obtain comprehensive information on pest management practices among farmers growing cabbage and cauliflower in India.A survey was conducted in the states of Gujarat, West Bengal, and Karnataka from October 2006 through January 2007. Three hundred farmers were interviewed to obtain information on pesticide use in cabbage and cauliflower production, the cost of pesticide use, and socioeconomic characters that influence cabbage and cauliflower production.Farmers relied on pesticides as the major and often exclusive crop protection strategy. Ten of the active ingredients (16.4% of all pesticides reported by all farmers in this survey) were listed as extremely or highly hazardous (classes Ia and Ib) by the World Health Organization. The results confirmed that pesticide use differs between states of India, but that location alone does not determine pesticide spraying pattern. A regression model was used to identify determinants of pesticide application frequency and pesticide cost per hectare. After controlling for location, individual level variables, such as age, education and experience, had significant effects on how often farmers sprayed. Farmers also spent more for pesticides, and sprayed more frequently on cauliflower than on cabbage and on open-pollinated varieties than on hybrid varieties.Our findings highlight the excessive use of pesticides in cabbage and cauliflower, and the reliance on pesticides as the only pest management strategy. The results confirm the need for alternative management strategies. Bt vegetables may be one of these alternative strategies. However, it is questionable whether cultivation of Bt vegetables will reduce the strong reliance on pesticides. Small-scale farmers will need training in the identification of pests, natural enemies, basic ecology, and integrated pest management strategies to ensure sustainable and safe vegetable production.  相似文献   

19.
Morus spp., commonly known as mulberry, is significantly associated with human civilization and spread of silk-culture from Asia to Europe, Africa and Latin America. One of its species, Morus laevigata, traditionally well known for its timber value, forage use and silkworm's feed, is widely distributed in India extending from Himalayan foothill to Andaman islands. The variability occurring for 12 morpho-biochemical parameters and RAPD profiles, generated with 13 selected RAPD primers, for M. laevigata accessions from six different zones were investigated. Analyses revealed high degree of genotypic similarity of collection from Himalayan foothill (West Bengal) with those from Andaman Islands. Specific accessions from central India and south India also revealed genotypic similarities with specific accessions from north-east India. These observations are discussed in the context of clonal propagation of mulberry and evolutionary perspective of dispersal of this species, through human activities  相似文献   

20.
Morphology of urediospores of stem rust of wheat, including shape, size and exterior adornment, has been investigated considering possible aerodynamic properties. This study included live and killed urediospores in an unhydrated and hydrated state. Density, mass measurements and physical counts of these materials were also compared. Observations of the urediospores include: a. Distribution of inner contents is reasonably homogeneous. Live urediospores possess a small amount of granular cytoplasm and one to several lipid globules. Killed urediospores possess only granular cytoplasm and lack the lipid globules. b. Live urediospores (unhydrated or hvdrated) are more dense and have a greater mass than do killed urediospores. Physical counts of killed urediospores per gram are greater than those of live urediospores in either the unhydrated or hydrated state. c. Live urediospores exhibit a characteristic bending and depression in the region of the germ pore. These characteristics are more pronounced in the killed urediospores. Hydration decreases the depression in both live and killed urediospores. d. Exterior adornment of urediospores consists of minute echinulae (curved spines) which may function in electrostatic or aerodynamic properties. e. Shape, bending, central thickness and external spines suggest possible aerodynamic properties of urediospores including a rotary motion which would permit greater long range travel.  相似文献   

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