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1.
The structure of heat exchange between the human body and its surroundings has been studied according to M.I. Budyko's model. Comparative measurements were carried out in the Polish Lakeland (maritime, temperate warm climate), in Central Mongolia (continental, temperate cool climate), and in the Kara Kum desert (dry subtropical climate). The results deal with the summer and early autumn seasons. The calculations indicate that the quantitative apportionment of various forms of heat exchange depend on specific weather conditions, which are typical for the distinguished climatic zones.  相似文献   

2.
荣亮  李恺  严莹  方燕 《昆虫知识》2009,46(5):772-777
于2007年4月~11月,对崇明岛不同季节昆虫群落多样性进行调查。选取6种不同生境,分别用物种丰富度、多样性指数、均匀度指数、相似性指数对不同的群落进行统计分析。共采集到昆虫标本约5800号,隶属于13目110科245种。数据表明,夏季的物种数目最多,春季次之,秋季最少。多样性指数以夏季的公园林地最高,秋季的西沙湿地最低。均匀度指数以春季的东滩湿地最高,秋季的西沙湿地最低。相似性指数以东滩湿地和西沙湿地相似性最高,为0.2769;海防林和小麦田最低,为0。结果表明,昆虫多样性与其所生活的环境有密切关系。  相似文献   

3.
This paper deals with the different effects of climate, and the likely impact of climatic change, on the human being, his health and well-being. Those effects follow from consideration of the human energy budget and air pollution, including photooxidants and radiation, the latter especially in the UV-range. The development of tools to produce bioclimate maps, i.e. maps expressed in physiologically significant terms, in different scales up to the high resolution necessary for the microscale urban climate, will be discussed. The most important questions in bioclimate research and its application will be considered.  相似文献   

4.
The carrying capacity of food resources for migrating shorebirds was estimated at a stopover site in the Yangtze River Estuary during the two migratory sea-sons (spring and autumn). From March to May and September to November 2005, the macrobenthos resources of the Jiuduansha Wetland were investigated, and most of the macrobenthos species in the newly-formed shoal were found to be appropriate food for shorebirds. Biomass measurements showed that the total food resource was about 4541.20 kg AFDW (Ash-Free Dry Weight) in spring and about 2279.64 kg AFDW in autumn. Calculations were also done in the available habi-tats (intertidal bare mudflat and Scirpus x mariqueter/ Scirpus triqueter zones) for the shorebirds. The food resources in the available areas were about 3429.03 kg AFDW in spring and about 1700.92 kg AFDW in autumn. Based on the classification (by lean weight, basic metabolic rate and body length) of the shorebird community, and using the energy depletion model, it was theorized that all of the food resources in the Jiuduansha Wetland could support about 3.5 million shorebirds during spring season and 1.75 million shorebirds during autumn season. The shorebird carrying capacities in terms of the available food were about 2.6 million and 1.3 million birds during the two respective migration seasons. Considering the effect of intake rate, the potential carrying capacity was about 0.13-0.26 million shorebirds in the study area. The main factor restricting use of the area by shorebirds was the scarcity of available habitats for roosting at high tide rather than availability of food supply. We recommend restoring some wading pools in the dense Phragmites australis and Spartina alterniflora zones for shorebirds to roost in, to improve shorebirds' utilization efficiency of the resources in the Jiuduansha Wetland.  相似文献   

5.
The carrying capacity of food resources for migrating shorebirds was estimated at a stopover site in the Yangtze River Estuary during the two migratory seasons (spring and autumn). From March to May and September to November 2005, the macrobenthos resources of the Jiuduansha Wetland were investigated, and most of the macrobenthos species in the newly-formed shoal were found to be appropriate food for shorebirds. Biomass measurements showed that the total food resource was about 4541.20 kg AFDW (Ash-Free Dry Weight) in spring and about 2279.64 kg AFDW in autumn. Calculations were also done in the available habitats (intertidal bare mudflat and Scirpus × mariqueter/Scirpus triqueter zones) for the shorebirds. The food resources in the available areas were about 3429.03 kg AFDW in spring and about 1700.92 kg AFDW in autumn. Based on the classification (by lean weight, basic metabolic rate and body length) of the shorebird community, and using the energy depletion model, it was theorized that all of the food resources in the Jiuduansha Wetland could support about 3.5 million shorebirds during spring season and 1.75 million shorebirds during autumn season. The shorebird carrying capacities in terms of the available food were about 2.6 million and 1.3 million birds during the two respective migration seasons. Considering the effect of intake rate, the potential carrying capacity was about 0.13–0.26 million shorebirds in the study area. The main factor restricting use of the area by shorebirds was the scarcity of available habitats for roosting at high tide rather than availability of food supply. We recommend restoring some wading pools in the dense Phragmites australis and Spartina alterniflora zones for shorebirds to roost in, to improve shorebirds’ utilization efficiency of the resources in the Jiuduansha Wetland. __________ Translated from Acta Ecologica Sinica, 2007, 27 (1): 90–96 [译自:生态学报]  相似文献   

6.
Proponents of evolutionary psychology take the existence of humanuniversals to constitute decisive evidence in favor of their view. Ifthe same social norms are found in culture after culture, we have goodreason to believe that they are innate, they argue. In this paper Ipropose an alternative explanation for the existence of humanuniversals, which does not depend on them being the product of inbuiltpsychological adaptations. Following the work of Brian Skyrms, I suggestthat if a particular convention possesses even a very small advantageover competitors, whatever the reason for that advantage, we shouldexpect it to become the norm almost everywhere. Tiny advantages aretranslated into very large basins of attraction, in the language of gametheory. If this is so, universal norms are not evidence for innatepsychological adaptations at all. Having shown that the existence ofuniversals is consistent with the so-called Standard Social ScienceModel, I turn to a consideration of the evidence, to show that thisstyle of explanation is preferable to the evolutionary explanation, atleast with regard to patterns of gender inequality.  相似文献   

7.
Three European plant phenological network datasets were analysed for latitudinal and longitudinal gradients of nine phenological ‘seasons’ spanning the entire year. The networks were: (1) the historical first European Phenological Network (1882–1941) by Hoffmann & Ihne, (2) the network of the International Phenological Gardens in Europe (1959–1998), founded by Schnelle & Volkert in 1957 and based on cloned plants, and (3) a dataset (1951–1998) that was recently collated during the EU Fifth Framework project POSITIVE, which included network data of seven Central and Eastern European countries. Our study is most likely the first, for over a century, to analyse average onset and year‐to‐year variability of the progress of seasons across a continent. For early, mid, and late spring seasons we found a marked progress of the seasonal onset from SW to NE throughout Europe, more precisely from WSW to ENE in early spring, then from SW to NE and finally from SSW to NNE in late spring, as exhibited by the relationship between latitudinal and longitudinal gradients. The movement of summer was more south to north directed, as the longitudinal gradient (west–east component) strongly declined or was even of opposite sign. Autumn, as shown by leaf colouring dates, arrived from NE to SW. Possible reasons for the differences among the three datasets are discussed. The annual variability of latitudinal and longitudinal gradients of the seasons across Europe was closely related to the North Atlantic Oscillation (NAO) index; in years with high NAO in both winter and spring, the west–east component of progress was more pronounced; in summer and autumn, the pattern of the seasons may be more uniform.  相似文献   

8.
Jane Norris-Hill 《Aerobiologia》1998,14(2-3):165-170
This paper attempts the prediction of the start of theBetula, Quercus andPlatanus pollen seasons in London, UK based on pollen sampling conducted over a 5-year period, 1987–1991. The times at which eight different thresholds of accumulated daily pollen counts (M−3) were passed were correlated against heat sums, chill units, accumulated sunshine hours, monthly meteorological parameters and the start dates of earlier pollen seasons to identify significant associations. Few meteorological parameters were significantly correlated with the start dates of the three pollen seasons, the exceptions being significant negative correlations between the average monthly air temperature in the months immediately preceding theBetula andPlatanus pollen season. However, significant relationships were identified between the start dates of theBetula, Quercus andPlatanus pollen seasons and the start of theCorylus, Taxus andPopulus pollen seasons with coefficients of determination as high as 98%. These indicator species were then used as predictors to forecast the start of theBetula, Quercus andPlatanus pollen seasons, both individually and in combination with one another, providing levels of explanation of up to 99%.  相似文献   

9.
Fifteen fungal species were found to be associated with seeds of three cultivars ofAmaranthus cruentus L. There was a seasonal variability in the frequency of isolation, distribution and quantity of these seed-borne fungi among cultivars. The wetness, high temperature and air humidity that accompanied harvests of the first and second seasons greatly increased the number and amount of seed-borne fungi. Least number and mean percentage seed infection were recorded for NHAc100 while NHAc30 and NHAc33 carried highest percentage inoculum of these pathogens. The seed testa of all cultivars was found to harbour the highest number and amount of some of these pathogens also in the second season. These seed-borne fungi,Choanephora cucurbitarum, Rhizoctonia solani andPythium aphanidermatum were highly pathogenic on seedlings of NHAc33 and NHAc30. Five of these seed-borne mycoflora have not been recorded onAmaranthus in Nigeria.  相似文献   

10.
The gonad maturation cycle of Siganus sutor (Valenciennes, 1835) (Osteichthyes-Siganidae) is described for both males and females using macroscopic criteria for the testes and both macroscopic and microscopic ones for staging the ovaries. Siganus suror has two major spawning seasons: one in January/February and the other in May/June. The presence of these seasons is established by (a) the temporal variations in the condition factor and in the relative weight of the gonads, (b) the progression of peaks of maturity stages with seasonal occurrence of spent fish in the samples, and (c) the seasonal appearance ofjuveniles. This is a significant result for a tropical marine fish.  相似文献   

11.
目的:了解临床工作实践中支气管哮喘防治指南(GINA方案)在基层医院的实施情况及遇到的问题并提出今后解决办法。方法:对门诊及病房住院的患者进行调查研究,采用统一设计的表格、问卷及必要的检查,对结果进行统计和分析。结果:正规治疗与非正规治疗的患者的花费情况具有明显差别,差异具有统计学意义。当地91.2%支气管哮喘曾经误诊为慢性支气管炎。治疗不规范,曾吸入激素治疗的占全部患者的18.1%,曾经和正在口服私人配制的平喘药物(粉剂或胶囊)的占65.8%;病情复发时给予输液、利用抗生素治疗的占73.6%;给予大剂量激素、不规范治疗(包括长期用激素治疗、不逐渐减量)治疗的78.7%;结论:当地哮喘治疗还存在很多问题,形式非常严峻,有待于进一步加大GINA治疗方案的推广。  相似文献   

12.
随机扩增多态DNA规范化反应体系的探讨   总被引:10,自引:0,他引:10  
在研究猪分子标记遗传距离同杂种优势的关系时 ,对模板浓度和纯度、引物浓度、dNTP浓度、Mg2 +浓度、不同商标的Tag酶等影响RAPD扩增的因素进行了系统的分析 ,在此基础上建立了适宜于本实验室研究的最佳RAPD技术体系 :2 5 μl反应体系中 ,含 10×buffer 2 .5 μl,MgCl2 1.75mmol/L ,dNTP 0 .2 5mmol/L ,引物 0 .2 4μmol/L ,Tag酶 2U ,模板 5 0~ 10 0 μg ,1μg/μlBSA。反应程序为 :94℃预变性 5min ,然后 94℃变性 1min ,36℃退火1min ,72℃延伸 2min4 0个循环 ,最后在 72℃延伸 10min。  相似文献   

13.
Milk cell counts are good indicators of a mammary infection and milk quality. The present study was done to record diurnal rhythmicity in the milk somatic and differential cell counts during different seasons, milk strips and parity in Murrah buffaloes. Milk somatic cell counts (SCC) were measured by SCC counter and milk differential cell counts were measured microscopically after making a milk smear and staining it to identify neutrophils, lymphocytes and macrophages. Maximum milk SCC was observed in the summer season. Milk neutrophils were lowest during thermoneutral (TN), intermediate during the winter season and highest during the summer season. Milk lymphocytes were highest during the winter season, intermediate in the TN and lowest in the summer season. Diurnal rhythm in the milk SCC and neutrophil percentage is noticed in the summer season only. Maximum milk SCC values were observed in the late strip but neutrophils were highest in the early strip. Diurnal rhythm was observed in the late strip for neutrophils and in mid strip for the lymphocytes. Milk SCC and milk neutrophils were found to be the highest in the multiparous buffaloes and diurnal rhythm was observed only in the lymphocytes of primiparous buffaloes. Milk macrophages were higher in the morning samples of primiparous as compared to the multiparous buffaloes. In this pioneer study, diurnal rhythms in the milk cell counts of buffaloes have been studied extensively. This will help in maintaining low milk cell counts in buffalo and thus help in getting more milk per buffalo during stress periods.  相似文献   

14.
中国香辛料产品加工标准体系研究   总被引:1,自引:0,他引:1  
在调研和综合分析我国香辛料产品加工现状基础上,根据标准化原理和标准化体系研究方法,首次系统地对我国香辛料产品加工体系进行研究,用三维坐标形式全面展示加工体系的层次、产品门类和过程要素之间的关系,体系表中的262项香辛料加工过程控制标准,为香辛料提供可靠的过程质量保障.  相似文献   

15.
    
The wind cooling effect determines wind chill equivalent-temperatures, which may be rather different to actual temperature. In a windy region such as Patagonia, this difference may reach a magnitude and persistence to become an important bioclimatic element. This paper quantifies the wind cooling effect in Patagonia by the presentation of equivalent isotherms as an adaptation of the usual isotherm maps to the regional bioclimatic environment. It is concluded that due to seasonal variations in wind speed, the annual equivalent temperature range is smaller than the actual temperature range, thus increasing oceanic features, from a thermal viewpoint, of the Patagonian climate.«Les vents que chassent, à travers une échancrure de la Cordillère des Andes, les hautes pressions du Pacifique, s'étranglent et s'accelèrent dans un étroit couloir de cent kilomètres de front, en direction de l'Atlantique, et raclent tout sur leur passage».Antoine de Saint-Exupéry «Un sens à la vie» (1956)  相似文献   

16.
17.
Dietary supplement Standard Reference Materials   总被引:1,自引:0,他引:1  
Sander LC  Sharpless KE  Wise SA 《Life sciences》2006,78(18):2044-2048
A new category of Standard Reference Materials (SRMs) based on dietary supplements is under development by the National Institute of Standards and Technology (NIST), with certified values for organic constituents and selected trace elements. These materials are provided primarily for use in method development and as control materials. The SRMs will assist manufacturers of dietary supplements in characterizing raw materials for potency, authenticity, and contamination or adulteration. In addition, the SRMs will assist in assessment of consistency and quality in finished products. The goal of this ongoing effort is to provide tools to the dietary supplement industry and measurement communities that will lead to improved quality of dietary supplements, and ultimately reduce public health risks that could potentially be associated with these products.  相似文献   

18.
About 45% of the total surface area of the Castile and Leon region today can potentially be occupied by semi-deciduous forests, chiefly dominated by Quercus faginea Willd. and Quercus pyrenaica Lam. On the basis of extrapolated trends in annual mean temperature and precipitation in Castile and Leon observed over the 37-year period from 1961 to 1997 [del Río et al. 2005], predicted changes in the areas covered by Q. faginea and Q. pyrenaica forests in 2025, 2050 and 2075 were made. A decrease in Q. faginea forests may occur if observed trends in temperature and precipitation continue. With respect to Q. pyrenaica forests, they may increase in present Mediterranean areas and decreases in Temperate Submediterranean areas. In some cases, both types of forests could be replaced by deciduous forests. The predicted results in the natural distribution of vegetation types by the bioclimatic models can be used to establish policies for improved future nature conservation and land management.  相似文献   

19.
20.
住院医师培训是医学教育中重要环节之一,是提高临床医疗水平的关键。因此,如何探索科学、合理的住院医师培养方案,已成为临床医学教育探索的重要课题。本文对肝胆外科住院医师规范化培训的实践进行了总结分析,希望对提高肝胆外科住院医师规范化培训效果起到一定的促进作用。  相似文献   

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