Life Sciences
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 Understory vegetation as environmental factors indicator in forest ecosystems
作者  Mataji, A.;Moarefvand, P.;Babaei Kafaki, S. & Madanipour Kermanshahi, M.
作者单位  
期刊  International Journal of Environment Science and Technology 卷期  Vol. 7, No. 4, 2010 时间  2011.01.17
关键词  Environmental factors; Herb layer; Multivariate analysis
摘要   Physiographic factors along with edaphic conditions play a crucial role in establishment of plant species throughout a region. Identification of the most effective factors is of high importance in sustainable management of a forest ecosystem. This study aims to investigate the relationships between understory vegetation and some environmental factors in natural forest ecosystems. This study has been carried out among the Fagetum orientalis communities of Ramsar Region, located in the north of Iran. For this purpose, 105 releves were sampled by a randomized-systematic method throughout the study area, using the Braun-Blanquet scale. Physiographic parameters such as elevation, as well as slope and orientation were measured. By identification of the herb-layer vegetation contained in each sampling, vegetation composition and cover abundance of species were separately identified. Then, the aforementioned properties of soil were entirely measured in the taken samples. Cluster analysis and detrended correspondence analysis have been applied to classify the site. Moreover, in order to determine the relation between species composition and environmental factors, canonical correspondence analysis was used. Results showed a significant relation between distribution of plant types and environmental factors. Eventually, environmental factors including slope, orientation, silt percent, pH, organic matter, soluble phosphorous were among the most effective factors in establishment of Hedera pastuchowii, Solanum kieseritzkii, Oplismenus undulatifolius, Sedum stoloniferum, Rubus hyrcanus and Saxifraga cymbalaria species.
 REVIEW ARTICLE - OLFACTORY DYSFUNCTION IN NEURODEGENERATIVE DISEASES
作者  M. Hakan Özdener, Nancy E. Rawson
作者单位  
期刊  European Journal of General Medicine 卷期  Vol. 1, No. 3, 2004 时间  2010.12.20
关键词  Olfactory dysfunction, neurodegenerative diseases
摘要   Interest in olfactory dysfunction has increased tremendously in the past decade, in part due to observations that chemosensory impairment is an early symptom of many neurodegenerative diseases. Several features of the olfactory system make it particularly relevant to understanding neurodegeneration/regeneration. First, while being vulnerable to environmental and infectious exposure, the olfactory system has the unique property of ongoing replacement of the olfactory sensory neurons under physiological conditions and following injury. Second, the receptor neurons residing in the periphery are developmentally related to the central nervous system, yet are accessible relatively noninvasively via biopsy from living subjects. Third, olfactory performance can easily be tested in a variety of ways that provide insight into the function of brain areas involved in detection, identification and memory. In addition to providing insights into the etiology or diagnosis of disease, a better understanding of olfactory neurobiology is needed to develop ways to treat olfactory dysfunction, which affects both quality of life and personal safety. At least 3,000,000 Americans suffer from chemosensory disorders and that is likely to grow as the aging segment of the population increases. Olfactory impairment represents a danger to the individuals resulting from inability to detect hazards as natural gas and spoiled food and threatens quality of life through the loss of enjoyment of foods and fragrances. The neurological systems responsible for olfactory function represent perhaps the most diverse, complex and adaptable components of the nervous system. Losses in olfaction result from changes at both the anatomical and molecular level. This loss can result from aging, toxins, infectious agents, environmental factors and a variety of diseases. Understanding the neurobiology of this sensory system may help us to develop new diagnostic measures and treatments for neurodegenerative disease as well as improving the quality of life for millions of people who are handicapped by the inability to detect the flavors and fragrances around them.
 Bacterial Indicators of Pollution of the Douala Lagoon, Cameroon: Public Health Implications
作者  Akoachere, Jane-Francis T. K.;Oben, Pius M.;Mbivnjo, Beryl S.;Ndip, Lucy M.;Nkwelang, Gerald & Ndip, Roland N.
作者单位  
期刊  African Health Sciences 卷期  Vol. 8, No. 2, 2008 时间  2010.08.23
关键词  Bacteria; Pathogenic; Coliform; Heterotrophic; Lagoon; Cameroon.
摘要   Background:Indiscriminate disposal of untreated wastes which are often heavily laden with sewage microorganisms some of which are pathogenic to humans into aquatic environments near cities could serve as potential dangers to human health. Objective:A prospective study was undertaken to investigate the scope of potential bacterial pathogens and to assess the extent of pollution of the Douala lagoon. Methods:A total of eighty water samples were collected fortnightly from the lagoon at five stations from March to October 2005 and analysed for heterotrophic bacterial densities, coliform counts, faecal coliform and faecal streptococcal counts. Bacteria were isolated and identified using standard microbiology and biochemical techniques. Results:High heterotrophic bacterial counts (33 × 105161 ×105CFU/ mL), total coliform counts (1.8 ×102- 2.4 ×102CFU/ 100 mL), faecal coliform counts (2.2 × 1022.4 × 102CFU/ 100 mL) and faecal streptococcal counts (2.1 × 1022.3 x 102CFU/ 100 mL) were observed in all sampling stations. Eleven species of bacteria:Bacteroidesfragilis,Proteusvulgaris,Klebsiellapneumoniae,E. coli,Enterococcusfaecalis,Enterobacteraerogenes,Citrobacterfreundii,Aeromonashydrophila,Pseudomonasaeruginosa,BacillusmycoidesandSerratiamarcesens, were frequently isolated. Conclusion:The presence of potential bacterial agents such asBacteroides fragilis,Pseudomonas aeruginosa,Aeromonas hydrophila,Klebsiella pneumoniaeandE. coliin the lagoon may pose a serious threat to the health and well being of users of the Lagoon and calls for urgent intervention.
 Ability of indigenous Bacillus licheniformis and Bacillus subtilis in microbial enhanced oil
作者  Haghighat, S.;Akhavan Sepahy, A.;Mazaheri Assadi, M. & Pasdar, H.
作者单位  
期刊  International Journal of Environment Science and Technology 卷期  Vol. 5, No. 3, 2008 时间  2010.08.23
关键词  Surface tension, emulsification activity, lipopeptide, crude oil, Bacilli
摘要   Microbially produced lipopeptide have been isolated and studied for microbial enhanced oil recovery. About 60 gram positive bacteria isolated from soil contaminated with crude oil, near the crude oil storage tank in Tehran Refinery, Tehran, Iran. However, most of these studies have produced lipopeptide by one of the pure-culture microbes isolated in a laboratory. Among the isolates, heamolytic tests revealed two biosurfactant producers. The isolated strains were designated as C2, E1. By using morphological, biochemical and molecular biology tests (16 SrRNA), the strains identified asBacillus licheniformisand Bacillus subtitlis, respectively. Emulsification activity and measurement of surface tension indicated that, the isolates were high producers of biosurfactant. The product of C2 and E1 is mainly lipopeptide. This product reduce surface tension from 65 to 30 mN/m. Emulsified activity of crude oil was 92% for C2 and 90 % in case of E1. This is the first report of indigenousBacillus licheniformisandBacillus subtilisfrom a soil contaminated with oil in an Iranian refinery with ability to produce biosurfactant.
 APPLICATION OF SEDIMENT QUALITY GUIDELINES IN THE ASSESSMENT OF MANGROVE SURFACE SEDIMENT IN MENGKAB
作者  Praveena, S. M.;Abdullah, M. H.;Aris, A. Z. & Radojevic, M.
作者单位  
期刊  Iranian Journal of Environmental Health Science and Engineering 卷期  Vol. 5, No. 1, 2008 时间  2010.08.11
关键词  Mangrove, sediment, sediment quality guidelines
摘要   There have been numerous sediment quality guidelines developed to monitor the sediments. Sediment quality guidelines are very useful to screen sediment contamination by comparing sediment contaminant concentration with the corresponding quality guideline, provide useful tools for screening sediment chemical data to identify pollutants of concern and prioritise problem sites and relatively good predictors of contaminations. However, these guidelines are chemical specific and do not include biological parameters. Aquatic ecosystems, including sediments, must be assessed in multiple components (biological data, toxicity, physicochemistry) by using intregrated approaches in order to establish a complete and comprehensive set of sediment quality guidelines. Numerous sediment quality guidelines Washington Department of Ecology Sediment Quality Guideline, Australian and New Zealand Environment and Conservation Council, Swedish Environmental Sediment Quality, Screening Quick Reference Table, Portuguese Legislation on the Classification of Dredged Materials in Coastal Zones and Interim Sediment Quality Guideline for Hong Kong) have been applied to the Mengkabong lagoon mangrove sediment and discussed. The most appropriate guideline that meets the prioritization criteria consistent with international initiatives and regulations is interim sediment quality values for Hong Kong. The guideline verifies that all the metals are below the Interim Sediment Quality Value-low. However, site-specific, biological testing and ecological analysis of exisiting benthics community structure related to sediment contamination are needed for final decision making in the case of Mengkabong lagoon.
 Intensifying Production Among Smallholder Farmers: The Impact of Improved Climbing Beans in Rwanda
作者  Sperling, L. & Muyaneza, S.
作者单位  
期刊  African Crop Science Journal 卷期  Vol. 3, No. 1, 1995 时间  2010.08.11
关键词  Central Africa, climbing beans, intensification, small farmer agriculture
摘要   While bush beans (PhaseolusvulgarisL.) have long been the protein staple of Rwandan agriculture, improved climbing beans have been introduced within the last 10 years, enabling farmers to intensify, stabilize and better stagger production. Through a 1992-3 nation-wide survey of 1050 households, conducted in both major growing seasons, this study examines the adoption of improved climbing beans across regions and potential user groups. Use of improved climbing beans, by 500,000 households, cross-cuts farm size, economic class and gender boundaries, and is most intensive among the more disadvantaged. Initial concerns with staking material, how to obtain and manage it, have posed relatively few problems for farmers, and the surprising plasticity of improved climbers has encouraged research to more closely determine soil fertility demands. Increased incidence of root rot (Fusariumoxysporum) and fear of reduced genetic variability on-farm have resulted in the Institut des Sciences Agronomique du Rwanda (ISAR's) adopting targeted pathogen screening procedures and releasing many new cultivars simultaneously. The success of improved climbers, bringing Rwanda an additional US$ 8 to 15 million per year, has stimulated promising R & D efforts in Kivu, Zaire and southern Burundi, and several other Eastern African regions have been identified as prime for climbing bean introduction.
 The Importance of Biosafety in the Deployment of Private Transgenic Sorghums in the Environment
作者  Shantharam, S.
作者单位  
期刊  African Crop Science Journal 卷期  Vol. 3, No. 2, 1995 时间  2010.08.11
关键词  Commercialization, transgenic sorghums, regulatory policiesCommercialisation, sorgho transgeniques, politiques regulatoires
摘要   This paper provides an overview of the concerns towards commercialization and deployment of transgenic sorghums. It also highlights the key role USDA/APHIS has played in the international harmonization of biotechnology regulatory policies.Ce papier donne un apercu sur les problemes lies a la commercialisation et la diffusion des sorgho transgeniques. I1 met aussi en evidence le role cle de I'USDA/APHIS dans l'harmonisation des politiques reglementant la biotechnologie.
 The Importance of Biosafety in the Deployment of Private Transgenic Sorghums in the Environment
作者  Shantharam, S.
作者单位  
期刊  African Crop Science Journal 卷期  Vol. 3, No. 2, 1995 时间  2010.08.11
关键词  Commercialisation, sorgho transgeniques, politiques regulatoiresCommercialization, transgenic sorghums, regulatory policies
摘要   Ce papier donne un apercu sur les problemes lies a la commercialisation et la diffusion des sorgho transgeniques. I1 met aussi en evidence le role cle de I'USDA/APHIS dans l'harmonisation des politiques reglementant la biotechnologie.This paper provides an overview of the concerns towards commercialization and deployment of transgenic sorghums. It also highlights the key role USDA/APHIS has played in the international harmonization of biotechnology regulatory policies.
 A study of neurologic symptoms on exposure to organophosphate pesticides in the children of agricult
作者  Rastogi, S. K.;Tripathi, S. & Ravishanker, D.
作者单位  
期刊  Indian Journal of Occupational and Environmental Medicine 卷期  Vol. 14, No. 2, 2010 时间  2010.07.27
关键词  Children, neurologic symptoms, OP pesticides
摘要   Pesticides are used extensively throughout the world in agriculture and in pest control as well as for community health purposes. Organophosphate (OP) pesticide self-poisoning is an important clinical problem in rural regions of the developing world that kills an estimated 200,000 people every year. Unintentional poisoning kills far fewer people but is an apparent problem in places where highly toxic OP pesticides are available. Neurologic dysfunction is the best documented health effect of pesticide exposure. High-level exposure has both acute and long-term neurologic signs and symptoms, and adverse effects have been reported in most type of pesticides, including organophosphate (OP), carbamate, organochlorine, and pyrethroid insecticides, herbicides, fungicides, and fumigants. Acute OP pesticide exposure can involve in wide range of both central and peripheral neurologic symptoms. Increased neurologic symptom prevalence may provide early evidence of neurologic dysfunctions, before clinically measurable signs are evident. In this study, we analyzed the cross-sectional data on neurologic signs and symptoms from 225 rural children, both males (n = 132) and females (n = 93) who were occupationally and paraoccupationally exposed to methyl OPs (dichlorvos, fenthion, malathion, methyl parathion) and ethyl OPs (chlorpyrifos, diazinon, ethyl parathion) as they belonged to agricultural families handling, mixing, and spraying the OP pesticides. The children completed a specially designed questionnaire (Q16) on neurologic symptoms associated with pesticide exposure with their parental help. A suitable reference group consisting of rural children (n = 50) never involved in pesticide handling (neither outdoor nor indoor) belonging to similar socioeconomic strata included in the study to compare the prevalence of various neurologic symptoms between the two groups. Among all the neurologic self-reported symptoms, headache, watering in eyes, and burning sensation in eye/face were the most important clinical manifestations attributed to OP pesticide exposure. These symptoms could probably be the consequence of chronic effects of most pesticides on the central nervous system. The muscarinic symptoms reported the maximum prevalence of salivation (18.22%), whereas lacrimation was observed in 17.33% cases, followed by diarrhea in 9.33% cases. The nicotinic clinical manifestations of acute OP poisoning revealed excessive sweating in 13.78% cases and tremors in 9.3% cases followed by mydriasis in 8.4% exposed children. The characteristic cholinergic symptoms, such as insomnia, headache, muscle cramps, weakness, and anorexia were also reported by both male and female exposed children. The high frequency of neurologic symptoms observed in the study may be due to parasympathetic hyperactivity due to the accumulated ACh resulting from AChE inhibition.
 A study of neurologic symptoms on exposure to organophosphate pesticides in the children of agricult
作者  Rastogi, S. K.;Tripathi, S. & Ravishanker, D.
作者单位  
期刊  Indian Journal of Occupational and Environmental Medicine 卷期  Vol. 14, No. 2, 2010 时间  2010.07.27
关键词  Children, neurologic symptoms, OP pesticides
摘要   Pesticides are used extensively throughout the world in agriculture and in pest control as well as for community health purposes. Organophosphate (OP) pesticide self-poisoning is an important clinical problem in rural regions of the developing world that kills an estimated 200,000 people every year. Unintentional poisoning kills far fewer people but is an apparent problem in places where highly toxic OP pesticides are available. Neurologic dysfunction is the best documented health effect of pesticide exposure. High-level exposure has both acute and long-term neurologic signs and symptoms, and adverse effects have been reported in most type of pesticides, including organophosphate (OP), carbamate, organochlorine, and pyrethroid insecticides, herbicides, fungicides, and fumigants. Acute OP pesticide exposure can involve in wide range of both central and peripheral neurologic symptoms. Increased neurologic symptom prevalence may provide early evidence of neurologic dysfunctions, before clinically measurable signs are evident. In this study, we analyzed the cross-sectional data on neurologic signs and symptoms from 225 rural children, both males (n = 132) and females (n = 93) who were occupationally and paraoccupationally exposed to methyl OPs (dichlorvos, fenthion, malathion, methyl parathion) and ethyl OPs (chlorpyrifos, diazinon, ethyl parathion) as they belonged to agricultural families handling, mixing, and spraying the OP pesticides. The children completed a specially designed questionnaire (Q16) on neurologic symptoms associated with pesticide exposure with their parental help. A suitable reference group consisting of rural children (n = 50) never involved in pesticide handling (neither outdoor nor indoor) belonging to similar socioeconomic strata included in the study to compare the prevalence of various neurologic symptoms between the two groups. Among all the neurologic self-reported symptoms, headache, watering in eyes, and burning sensation in eye/face were the most important clinical manifestations attributed to OP pesticide exposure. These symptoms could probably be the consequence of chronic effects of most pesticides on the central nervous system. The muscarinic symptoms reported the maximum prevalence of salivation (18.22%), whereas lacrimation was observed in 17.33% cases, followed by diarrhea in 9.33% cases. The nicotinic clinical manifestations of acute OP poisoning revealed excessive sweating in 13.78% cases and tremors in 9.3% cases followed by mydriasis in 8.4% exposed children. The characteristic cholinergic symptoms, such as insomnia, headache, muscle cramps, weakness, and anorexia were also reported by both male and female exposed children. The high frequency of neurologic symptoms observed in the study may be due to parasympathetic hyperactivity due to the accumulated ACh resulting from AChE inhibition.
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