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911.
Central Asian water planning following international policy recommendations and ‘blue prints’ has caused more harm rather than benefiting local communities. International research has not been sufficient to contribute in practical terms to water and food security. This paper reflects potential factors that limit understanding the complexity of water management in Central Asia. Five factors are identified which prevent cross linking of research across international boundaries and within countries. These are: (1) language, (2) access, (3) wikipediarism, (4) smattering and (5) outdating. To change the situation two factors are still missing – a lost generation of local experts and an internal critical review.  相似文献   
912.
Background : Diagnosis of neuro-inflammatory conditions in the horse can be challenging. Current methods include evaluation of cerebrospinal fluid (CSF) for inflammation and determination of specific antibody status. The antibody index (AI) and Goldman-Witmer coefficient (C-value) can be used to aid in the interpretation.
Hypothesis : The null hypothesis to be tested was that the AI and C-values do not change in horses with neuro-inflammation.
Animals : Twelve horses of various ages (3–17 years) and breeds (Thoroughbred, Thoroughbred cross, draft, and Arabian) were included in the study.
Methods : The study was designed as a prospective randomized study. All horses were immunized with ovalbumin in adjuvant, twice. Horses of Group 1 then were challenged by intrathecal (IT) injection of ovalbumin, whereas horses of Group 2 were challenged IM. The AI and C-values for ovalbumin and equine herpesvirus were calculated.
Results : The AI for ovalbumin increased up to 5.92 in horses after intrathecal challenge, and remained normal (<1) in horses challenged IM. The C-value for ovalbumin reached a peak of 7.48, whereas for equine herpesvirus it achieved a value of 2.69. The changes in ovalbumin C-value and AI were significantly different between days 20 and 30 in horses after intrathecal challenge at day 20 ( P = .002 and .0005, respectively).
Conclusions and Clinical Importance : The results confirm the value of the AI and C-value in the evaluation of neuro-inflammation in the horse.  相似文献   
913.
In the summer of 2010 an epidemic of West Nile virus (WNV) occurred in Central Macedonia, Greece, with 197 human neuroinvasive disease (WNND) cases. In the following years the virus spread to new areas, with a total of 76 WNND cases in 2011, and 109 WNND cases in 2012 (14 and 12 WNND cases, respectively, in Central Macedonia). We established a surveillance system based on serological testing of domestic pigeons, using cELISA confirmed by serum neutralization test. In Central Macedonia, pigeon seroprevalence was 54% (95% CI: 49–59%) and 31% (95% CI: 24–37%) at the end of the 2010 and 2011 epidemic seasons, respectively. One serum was positive for neutralizing antibodies directed against Usutu virus. Pigeon WNV seroprevalence and incidence rates of human WNND after the 2010 epidemic were positively correlated (ρ = 0.94, at the regional unit level), while in 2011 the correlation (ρ = 0.56) was not statistically significant, possibly due to small number of human WNND cases recorded. To evaluate the efficacy of the system at alerting upon WNV enzootic circulation before the onset of human cases, we tested 270 pigeons in 2011 and 240 pigeons in 2012. In Central Macedonia, the first seroconversions in pigeons were recorded 44 and 47 days, respectively, before the first human WNND cases. Pigeon surveillance was used successfully for identification of areas with WNV enzootic transmission and for early warning. Timely diffusion of information to health authorities facilitated the implementation of preparedness plans to protect public health.  相似文献   
914.
Mycoplasma suis, the causative agent of porcine infectious anemia, causes large economic losses to the swine industry worldwide. A questionnaire-based survey was conducted in 69 pig farms in Hubei Province, China, from November 2011 to August 2013 to ascertain the prevalence and associated risk factors of M. suis. Four thousand and four blood samples from pigs of all the age groups were tested for M. suis antibodies using the established rMSG1–ELISA assay. Among these 4004 samples, 1615 blood samples from multiparous sows were examined to identify the association between seroprevalence and different seasons. Information on risk factors collected from farmers or attending veterinarians was recorded on a pre-designed questionnaire. The overall test seroprevalence of M. suis infection at the animal level was 31.9% (1277/4004; 95% CI: 30.5%, 33.4%), whereas at the farm level, this value was 95.65% (66/69; 95% CI: 87.8%, 99.1%). The seroprevalence of M. suis was higher in replacement gilts (40.6%; 95% CI: 35.1%, 46.3%), multiparous sows (48.2%; 95% CI: 45.8%, 50.7%) and boars (44.4%; 95% CI: 34.5%, 54.8%), as compared to piglets (13.0%; 95% CI: 9.4%, 17.3%), weaned-piglets (10.8%; 95% CI: 8.9%, 13.0%), and growing-finishing pigs (25.0%; 95% CI: 22.0%, 28.3%). In terms of seasons, the prevalence of M. suis in pigs was significantly higher in summer (65.3%; 95% CI: 61.0%, 69.5%) and autumn (65.0%; 95% CI: 59.0%, 70.6%) compared to spring (30.1%; 95% CI: 26.0%, 34.4%) and winter (36.4%; 95% CI: 31.4%, 41.5%). Farm-level risk factors were identified by multivariable logistic regression analysis. The associated factors retained in the final multivariable logistic regression model were drug treatment, presence of mosquitoes and flies, and frequency of disinfection. Drug treatment (OR = 0.24; 95% CI: 0.07, 0.88; P = 0.031) and frequency of disinfection (OR = 0.23; 95% CI: 0.06, 0.90; P = 0.035) were protective factors, and the presence of mosquitoes and flies (OR = 5.994; 95% CI: 1.56, 23.00; P = 0.009) was a risk factor for M. suis infection on farms. The results of the present study provide the first insight into the impact of associated determinants on M. suis infection in central China.  相似文献   
915.
916.
大西洋中部金枪鱼延绳钓渔场大眼金枪鱼的生物学特性   总被引:8,自引:3,他引:8  
宋利明 《水产学报》2004,28(2):216-220
Based on the biological data of bigeye tuna measured from the longlining ground of the Central Atlantic Ocean from Jun. 2001 to Oct. 2001, this paper analyzed the bigeye tuna‘s maturity stages of the gonad, feeding intensity, species composition of prey, sex ratio, fork length distribution, relationships between fork length and dressed weight, fork length and round weight, round weight and dressed weight by statistic and regression methods. The results indicate: ( 1 ) Maturity at Ⅳ-Ⅵ of the gonad are dominant with the highest percentage of Ⅴ (30.11% ). (2)The feeding intensity is mainly in the class 1 ,class 2 or class 3,totally 83.16%. (3)In the bigeye tuna‘s species composition of prey, the percentage of miscellaneous fish or cephalopod is relatively high, 38.05 % or 30.48 % respectively. Catch rate of bigeye tuna can be enhanced when cephalopod is used as the bait. (4) The male-female ratio is 2 : 1. This pattern might result from elevated mortality of adult females. (5) The fork length distribution is suitable for the normal. The dominant fork length is 1.13 - 1.49m, 64.16%, with the mean value of 1.32m. (6)The relationship between fork length and dressed weight. (7)The relationship between fork length and round weight. If the fork length is the same, the round weight converted in this paper‘s formula is a little lighter than the round weight converted in Parks‘s formula concluded at 1981 of the longline bigeye tuna catch. It might be caused by the different sampling areas or sampling time. (8)The relationship between round weight and dressed weight. The round weight conversion factor in this paper is a little higher than the ICCAT. It might be caused by the different processing methods. ICCAT is recommended to adapt this paper‘s conversion factor.  相似文献   
917.
大西洋中部大眼金枪鱼垂直分布与温度、盐度的关系   总被引:11,自引:2,他引:11  
根据2001年7月4日至10月27日3艘在大西洋中部公海海域作业的中国金枪鱼延绳钓船上随机观测到的大眼金枪鱼(Thunnus obesus)的上钩钩号,应用悬链线钩深计算公式,分别计算出各钩号的钩深;根据STD仪测得的温度、盐度的垂直分布以钩深为引数,查出该尾鱼捕获时的温度和盐度数据。根据大眼金枪鱼的取样数据,利用频度统计的方法,推算出各水层、水温、盐度范围的渔获率。渔获率最大的水层、水温、盐度范围为大眼金枪鱼的最适水层、水温和盐度范围;渔获率为前3位的水层、水温、盐度范围为大眼金枪鱼活动较频繁的水层、水温和盐度范围。结果表明:大西洋中部,大眼金枪鱼的最适水层为240.00~269.99m水深、最适水温为12.00~12.99℃、最适盐度为35.00~35.09;大西洋中部渔场大眼金枪鱼活动较频繁的水层为240.00~329.99m水深、水温为10.00~12.99℃、盐度为35.00~35.29。  相似文献   
918.
刘勇  陈新军 《海洋渔业》2007,29(4):296-301
黄鳍金枪鱼是中西太平洋金枪鱼围网渔业中的重要捕捞种类之一。本文根据2003年中西太平洋金枪鱼围网生产统计及其表温数据,利用频次统计分析和地理信息软件Marine Explorer 4.0对黄鳍金枪鱼产量和单位日产量(CPUE)的时空分布进行分析,探讨其与海水表温的关系。结果显示,产量和CPUE最高的是2月份,其次是9月份,5月份为最低。高产量的范围为140~160°E、0°~5°S;CPUE高值区分布在130°E、0°~15°S,140°~160°E、0°~15°S和175°W、0°~15°S;产量经纬度重心分别为150°30′E和3°48′S。产量主要分布在海表温为28~31℃的海域,产量比重高达95.45%,其中29~30℃产量为最高,占69.54%。  相似文献   
919.
Owing to humid climate and unfavourable relief, the problem of extensive soil erosion in central Croatia is of prime importance. The main objective of this research was to determine how soil erosion is influenced by deep (30 cm) soil tillage practised for deep-rooted row crops in comparison with other tillage methods, on Stagnic Luvisols. Soil loss quantity was recorded during the 4-year investigation cycle (1994–1998), under common field crops grown under six tillage methods. Appreciably higher rates of soil erosion were recorded in low-density row spring crops than in high-density winter crops under the same tillage methods. The time immediately following the sowing of spring crops was the most critical period, i.e. the period when highest soil loss occurs. The results showed that erosion processes cannot be completely stopped; however, they can be reduced to an acceptable level by an appropriate tillage method. Efficient soil conservation on Stagnic Luvisols was achieved by no-tillage and all across the slope tillage methods.  相似文献   
920.
黄土高原水土保持世行贷款项目监测评价研究初探马国力,朱小勇(西安黄委会黄河上中游管理局,西安710043)黄土高原水土保持世行贷款项目区分布在黄土高原沟壑区、黄土丘陵沟由区和风沙区三个不同类型区,包括听水河、蔚汾河、河(曲)保(德)偏(关)片、罕台川...  相似文献   
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