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91.
92.
Broman E  Wallin K  Stéen M  Cederlund G 《Ambio》2002,31(5):409-416
In the 1980s, people in Sweden frequently responded to moose (Alces alces) found dead or in poor physical condition. The number of moose submitted for routine investigations to the National Veterinary Institute (SVA) increased tenfold and the hunters in Alvsborg County were especially concerned. Later, a complex wasting syndrome was described and reports of moose suffering from the syndrome have been collected since 1991. Today, there is no definitive answer as to the underlying causel(s) of the syndrome, but there are several plausible hypotheses that can be divided into two groups: food-related and host-parasite related. The food-related hypotheses are postulated to have any of the following ultimate causes: acidification/liming, browser density/food production or pollution. Our view is that few of the hypotheses have been critically tested. Most of the hypotheses are supported by some observations, which is to be expected because these are post-hoc attempts to explain these very observations.  相似文献   
93.
Kazakhstan is an upper-middle-income country and one of the coldest countries in the world with rich energy resources and energy prices considerably lower than in developed countries. This paper presents the first comprehensive overview of household fuel use in Kazakhstan and assesses the causes and extent of energy poverty using the Households Living Conditions Survey dataset of 12,000 households. The results show that there is an overwhelming reliance on coal in Kazakhstan: 40% of all surveyed households use coal for heating, cooking and other needs. In general, liquefied petroleum gas is mainly used for cooking, coal and firewood for heating, while electricity is rarely used for heating. Energy poverty was less prevalent in oil and gas rich regions, due to low gas prices and higher income levels in those regions, while households located in the North Kazakhstan, Central and East Kazakhstan mainly suffer from lack of cleaner fuel options, income poverty, longer and colder winters and consequently energy affordability. Despite low energy prices in Kazakhstan, the results demonstrate that 28% of surveyed households spend more than 10% of their income on energy. Gas and district heating infrastructure coverage and income inequality across its regions contributed the most to energy poverty in Kazakhstan. Energy prices are regulated and indirectly subsidised. Removing energy subsidies alone may worsen energy affordability of households. Offering direct subsidies to cover part of the energy expenditures may not fully solve the problem, but subsidies, interventions for efficient technologies and fuels, dwelling energy-efficiency improvements are necessary.  相似文献   
94.
Lead (Pb) concentrations in 398 samples of dog whole blood were determined by atomic absorption method. All samples were within the normal range of values reported in literature, 95% of the samples had <8.0 g/100 ml lead. The correlation between blood lead level and the volume of traffic was highly significant. About 11% of the variability in concentration can be explained by the traffic flows near the animal's home. The findings confirm that traffic contributes a significant portion of the total inhaled lead. The use of dogs as environmental lead monitors is discussed. It is concluded that in non-occupational situations a survey of lead in blood of dogs may serve as a feasible, low-cost alternative to large-scale surveys of humans.  相似文献   
95.
The Mariánské Lázn complex (MLC) is located in the Bohemian Massif along the north-western margin of the Teplá-Barrandian microplate and consists of metagabbro, amphibolite and eclogite, with subordinate amounts of serpentinite, felsic gneiss and calcsilicate rocks. The MLC is interpreted as a metaophiolite complex that marks the suture zone between the Saxothuringian rocks to the north-west and the Teplá-Barrandian microplate to the south-east. Sm-Nd geochronology of garnet-omphacite pairs from two eclogite samples yields ages of 377±7, and 367±4 Ma. Samples of eclogite and amphibolite do not define a whole rock Sm-Nd isochron, even though there is a large range in Sm/Nd ratio, implying that the suite of samples may not be cogenetic. Eclogites do not have correlated Nd values and initial 87Sr/86Sr ratios. Five of the eight eclogite samples have high Nd values (+10.2 to +7.1) consistent with derivation from a MORB-like source, but variable 87Sr/86Sr ratios (0.7033 to 0.7059) which probably reflect hydrothermal seawater alteration. Three other eclogite samples have lower Nd values (+ 5.4 to –0.8) and widely variable 87Sr/86Sr ratios (0.7033 to 0.7096). Such low Nd values are inconsistent with derivation from a MORB, source and may reflect a subduction or oceanic island basalt component in their source. The MLC is an important petrotectonic element in the Bohemian Massif, providing evidence for Cambro-Ordovician formation of oceanic crust and interaction with seawater, Late Devonian (Frasnian-Famennian) high- and medium-pressure metamorphism related to closure of a Saxothuringian ocean basin, Early Carboniferous (Viséan) thrusting of the Teplá terrane over Saxothuringian rocks and Late Viséan extension.  相似文献   
96.
20世纪80年代,在瑞典人们经常发现驼鹿死亡或身体状况差的情况.递交给瑞典国立兽医研究所(SVA)进行尸体常规检查的驼鹿数目增加了10倍之多.艾尔夫斯堡(Alvsborg)的狩猎者们对此尤为关注.随后,人们对驼鹿这一复杂的萎缩综合症进行了相关描述并从1991年开始收集有关患病驼鹿的报道.迄今为止,仍未找到该综合症确定的潜在病因,但人们提出了一些可能的假说以解释此综合症.这些假说基本上可以分为两类:食物相关假说和宿主-寄生虫相关假说.食物相关假说认为萎缩综合症有如下根本原因:酸化/撒石灰、采食动物密度/食物产量或污染.上述假说很少经严格实验检验,多半实验仅为一些观察结果支持,之所以这些假说与人们的预计相吻合,是因为这些假说是事后试图解释这些观察到的现象而提出的.  相似文献   
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99.
为了评价东非不同空间尺度(1m尺度~l00km尺度)红树林分布区等足类甲壳动物蛀木虫钻刺团水虱(团水虱属)在美国红树红茄冬气生根中出现的情况,进行了野外调查研究.  相似文献   
100.
Food and Environmental Virology - The main animal reservoirs of zoonotic hepatitis E virus (HEV) are domestic pigs and wild boars, but HEV also infects cervids. In this study, we estimated the...  相似文献   
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