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Summary As a prisoner of war the writer was working for nearly three years in different POW camps, and outside them, along the Burma railway from Thanbyuyzat in southern Burma up to Kanchanabury in Thailand. In the army of the Netherlands-Indian archipelago (KNIL) he had the military rank of reserve horse-doctor. In civilian life he was attached to the Veterinary Institute in Buitenzorg (now Bogor) as a veterinary bacteriologist. His task as a POW became that of meathygienist and supervisor of the living animals in the camps. In this function he diagnosed swine fever in growing pigs which had mainly been fed on the offal of the Japanese kitchen. The acute course and the pathological alterations observed during the post-mortem examinations were identical with those of the Southern-African type of the disease. In slaughter cattle the author diagnosed some cases of lung tuberculosis, one of anthrax, several of rinderpest, some of rhinal granulomatosis and one of foot and mouth disease. In chickens he found NCD (pseudo-fowlpest) and in ducklings a mortal disease which the author then called 'keeling disease' but which he many years later, recognized as virus hepatitis. As assistant bacteriologist and ex-POW he joined the British regimental hospital in Bangkok. Here he had the opportunity to assist the bacteriologist pathologist, Maj. C. R. Peck IMS / IAMC in diagnosing the first case of melioidosis in an ex-POW of the KNIL who died from the sub-acute infection, notwithstanding treatment in the hospital with sulfa-drugs and penicillin.  相似文献   
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The use of Trichogramma egg parasitoids has further increased. T. brassicae, released against the European Corn Borer Ostrinia nubilalis, holds the largest share in Germany with 11,000 hectare. For small-scale fruits crops the commercial use of T. cacoeciae and T. dendrolimi against the Codling Moth (Cydia pomonella) and the Plum Moth (Grapholita funebrana) has been expanded. Trichogramma species are also being offered for controlling the vine moths, Lobesia botrana and Eupoecilia ambiguella on grapevine in homegardens. A strain of T. evanescens is available against cabbage pests, especially noctuids. Research has been conducted on the biological control of Autographa gamma in spinach, as well as of the Pea Moth (Cydia nigricana) and the Leek Moth (Acrolepiopsis assectella) in organic farming. Trichogramma is also important for the biocontrol of exotic pests in greenhouses. These are often polyphagous pests that have been introduced together with ornamental plants, such as Duponchelia fovealis and Clepsis spectrana. The Carnation Tortrix (Cacoecimorpha pronuba) was successfully controlled by Trichogramma in the field. The use of Trichogramma has been further established for the control of storage pests. T. evanescens is used against the Indian Meal moth (Plodia interpunctella) in stored cereal products. Other target pests in storage environments are Ephestia kuehniella and Sitotroga cerealella. In addition, Trichogramma species have been tested for the control of the Common Cloths Moth (Tineola bisselliella) under laboratory conditions. The range of target pests for Trichogramma egg parasitoids has therefore increased considerably in research and commercial applications in Germany.  相似文献   
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In the Upper Zambezi and Okavango ecoregions, Brycinus lateralis, Hepsetus cuvieri, Schilbe intermedius and Serranochromis macrocephalus are important in subsistence fisheries, while S. intermedius and S. macrocephalus are often caught in commercial catches. Despite their importance, there is little information on their age and growth and age validation. Growth zone deposition rate in otoliths of B. lateralis, H. cuvieri, S. intermedius and S. macrocephalus was validated as annual using edge analysis in this study. Annual deposition of growth zones was corroborated by a fluorochrome marking experiment. Both methods demonstrated that one growth zone was deposited annually. Edge analysis demonstrated that the highest proportion of opaque zones was detected between August and December, most likely as a result of slow growth during lower temperature water during the preceding winter. With growth zone deposition validated as annual, future research should focus on determining the growth, maturity and mortality rates of these species, parameters which are important for their management.  相似文献   
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Olaf Erenstein   《Agricultural Systems》2006,90(1-3):132-158
The paper analyses whether the increased use of lowlands in proximity to urban centres in West Africa is associated with technological intensification or extensification. Technologies are typified in terms of their orientation – land or labour saving – and market dependence for their procurement and reviews the factors driving and modifying their use in lowlands. The factors associated with technology use are analyzed empirically using geo-referenced lowland data around four urban centers along an ecological gradient in Côte d’Ivoire and Mali. The technologies analyzed include both external inputs (fertilizer, pesticide, herbicide, improved varieties) and crop management practices (plot level bunding, rice transplanting and rice direct seeding). Results from binomial logit models highlight the prominent positive and non-linear role of proximity to urban markets for the technological intensification of lowlands – an issue associated with factor scarcities and the transaction costs for procurement and marketing. Technology use in lowlands is also associated with the agro-ecological gradient, lowland development and non-native lowland users. A common thread linking these variables is that they modify resource scarcity and therefore intensification incentives. Lowlands are not always as valuable as they may seem and there may be limited incentives to intensify. Instances of significant lowland cultivation and intensification in the study sites tend to be associated with specific opportunities – driven by market opportunities and modified by seasonal, institutional or development-induced relative land scarcity. Market access is therefore a necessary but not sufficient factor for the technological intensification of lowland use. There is a need for better targeting of development efforts in terms of enabling lowland intensification or extensification as appropriate.  相似文献   
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There is considerable interest in the spatial distribution of Echinococcus multilocularis in red foxes (Vulpes vulpes L.), because this parasite causes the zoonoses of alveolar echinococcosis which is potentially of high fatality rate. High risk areas are known from France, Switzerland and the Swabian Alb in Germany for a long time. In this work, the spatial scan statistic is introduced as an instrument for identification and localisation of high risk areas, so called disease clusters in spatial epidemiology. The use of the spatial scan statistic along with data about the distribution of the parasite in 5365 red foxes in Lower Saxony, that were collected during 1991 to 1997, led to the identification of another high risk area. The relative risk for this disease cluster is approximated by RR = 5.03 (CI0.95(RR) = [4.27; 6.58]) for the period of 1991 to 1994 and by RR = 4.45 (CI0.95(RR) = [3.53; 5.59]) for the period of 1994 to 1997, respectively.  相似文献   
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Giardia lamblia which parasitize humans belong to either of two genotypes, A or B, based on specific signature sequences in the 5' end of the small subunit (16S) ribosomal RNA (rRNA) gene. These two genotypes also were found in cysts from fecal samples of animal origin such as dogs, cats, some farm animals and wild animals. In addition, trophozoites recovered from cysts obtained from environmental samples belonged to these two genotypes as well, suggesting that the G. lamblia genotypes A and B are widespread and possibly zoonotic. Trophozoites were recovered from rats and these isolates might belong to another genotype of G. lamblia. Deer mice and one dog appeared to be parasitized by genotypes of Giardia with close affinity to G. microti. This species, therefore, also consists of a genotype complex.  相似文献   
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