102 research outputs found

    Discussion of Possible Semantic Description for Documents Based on Analysis of Predicate-Argument Structure

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    動詞間で共通する意味属性を考慮して,シソーラス上に整理した動詞項構造シソーラスを提案し,形容動詞まで拡張して分析を進めてきた.動詞項構造シソーラスの背景には語彙概念構造という状態変化を主に記述する形式を拡張してきたが,「必要だ」や「必ず〜する」といった主観的な内容を記述する場所が無く,意味記述の中に自然言語で埋めることになっている.本稿では述語の分析から必要となる意味構造の要件を明らかにする.その中でも可能世界意味論に関係している点を事例をもとに明確化し,文書解析のための意味構造について考察する.さらに,人工知能で議論されてきた様相論理,動的命題,設計学,オントロジー工学との関係について概観する.The results of our previous work of construction of Japanese verb thesaurus revealed that a verb meaning often contains not only action or change-of-state meaning, i.e., objective meaning, but subjective meanings. To describe verb meaning, lexical conceptual structure was applied, but it does not have a place of subjective and modal meaning; then they are described using natural language embedded in an extended LCS-based schema. Modal logic gives us a description framework, but verb meanings have more complex meaning, such as event attributes, progress and possibility. In the manuscript we summarize the wide variety of verb and adjective verb meaning from the view of change-of-state and subjective meaning, then discuss a description framework of them according to modal logic study

    Leverikten: en gammel kending i fremgang

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    Liver flukes are very successful group of parasites that can infect many different hosts including humans. They can be found in different forms and sizes, and found almost all of the world. In Denmark, two species are found. The well-known "common liver fluke" has existed in Denmark since the Vikings, but is increasing again recently. Not so known is "the lancet fluke", which is also fascinating as it can make the ants behave like zombies

    Farm-level risk factors for Fasciola hepatica infection in Danish dairy cattle

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    Recent studies suggest that liver fluke (Fasciola hepatica) infections in cattle have increased in Denmark in recent years. This study aimed to identify potential farm level risk factors for liver fluke infection in Danish dairy farms using two different diagnostic methods. Based on liver condemnation data of all individual cattle slaughtered in Denmark, 145 and 77 farms were selected as cases and matched controls. The selection criteria were; 1) minimum 50 animals were slaughtered in 2013, 2) minimum three cases of liver condemnation due to liver flukes in 2013 (case) / no history of liver condemnation due to liver flukes for the last three years (control), and 3) control farms were located within 10 km from the case farms. Bulk tank milk (BTM) samples from the farms were analysed using enzyme-linked immunosorbent assay (ELISA), and telephone interviews were used to obtain information on the type of production, the farmers’ knowledge about liver fluke infection, grazing pattern, anthelmintic treatments and management routines. Preliminary results based on 132 case and 64 control farms indicate that grazing was significantly associated with liver fluke infection (p=0.006). However, in 12 case herds, grazing was not applied (all-in systems), suggesting indoor rearing does not completely prevent liver fluke infections, although misdiagnosis or incorrect registration at slaughter is possible. The percentage of farms allowing heifers to graze on wet areas was significantly higher in case than control farms (p<0.001). Using grazing for heifers and drinking from natural waterways were associated with liver fluke infections (p=0.07 and p=0.01). Approximately 30% of case farms tried actively to avoid infection by anthelmintic treatment or preventive management measures. The prevalences of liver flukes estimated by BTM ELISA were 75% and 12.5% for case and control groups, respectively. The negative ELISA results in some of the case herds may be due to their low in-herd prevalence, but it is still under investigation. Based on the risk analysis, we expect grazing management can be improved on many infected farms as part of the control of liver fluke. The substantial discrepancy between different diagnostic methods should be taken into account for future studies

    Effect of disinfectants on viability of Ascaris suum and Ascaridia galli eggs

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    Ascaris suum and Ascaridia galli, the large round worm of pigs and poultry, respectively, persist even in intensive management systems, where a high level of hygiene is practiced. It is necessary to control these helminths to minimize production losses and improve animal welfare. Commercial disinfectants are commonly used to clean pens in conventional pig and poultry farms but their efficacy against the thick-shelled nematode eggs has not been sufficiently documented. However, it might be difficult to control these parasites because of their complex thick-shelled eggs, which can resist harsh environmental conditions. Commonly used disinfectants such as Virkon S®, FL-des GA® typically claim efficacy against viruses, bacteria and some fungi, but very few disinfectants (FL-des Allround®) claim to also eliminate parasite eggs

    Farm specific transmission patterns of Fasciola hepatica in Danish dairy cattle based on different diagnostic methods and monitoring of grazing management

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    A recent survey based on meat inspection data showed that approximately 30% of Danish cattle farms were infected with liver flukes, leading to significant economic losses. Despite the widespread problem, up-to-date knowledge on transmission patterns, diagnostic methods and practical measures for control is still lacking. We therefore initiated a longitudinal, observational study in a few infected dairy farms to elucidate farm specific transmission patterns based on different diagnostic methods and grazing management. Two organic and two conventional dairy farms with high F. hepatica antibody levels in bulk tank milk were selected. From each farm a cohort of 40 animals from different age groups (calves, heifers, primiparous and multiparous cows) were sampled 7 times between April 2015 and January 2017. Diagnostic methods included faecal egg count by sedimentation, serum ELISA and coproantigen ELISA. Additionally, monthly bulk tank milk samples were analyzed by ELISA. The analyses are ongoing, but preliminary results indicate that F. hepatica is mainly transmitted via summer infection of snails as most animals seroconvert in late autumn without shedding of eggs. However, infection early in the grazing season due to overwintered snails has also been observed. One farm where cows are stabled have had some older cows continuing to shed F. hepatica eggs, suggesting long life span of F. hepatica, although other routes of infection cannot be ruled out. The final results will provide novel and practical information about different diagnostic tests and transmission patterns related to grazing management on farm-level

    Farm-level risk factors for Fasciola hepatica infection in Danish dairy cattle as evaluated by two diagnostic methods

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    The prevalence of bovine fasciolosis in Denmark is increasing but appropriate guidelines for control are currently lacking. In order to help develop a control strategy for liver fluke, a risk factor study of farm management factors was conducted and the utility of bulk tank milk (BTM ELISA) as a tool for diagnosis in Danish dairy cattle farms was assessed. This case-control study aimed to identify farm-level risk factors for fasciolosis in Danish dairy farms (&gt; 50 animals slaughtered in 2013) using two diagnostic methods: recordings of liver condemnation at slaughter, and farm-level Fasciola hepatica antibody levels in BTM. A case farm was defined as having a minimum of 3 incidents of liver condemnation due to liver fluke at slaughter (in any age group) during 2013, and control farms were located within 10 km of at least one case farm and had no history of liver condemnation due to liver fluke during 2011-2013. The selected farmers were interviewed over telephone about grazing and control practices, and BTM from these farms was collected and analysed by ELISA in 2014. The final complete dataset consisting of 131 case and 63 control farms was analysed using logistic regression. Heifers grazing on wet pastures, dry cows grazing on wet pastures, herd size, breed and concurrent beef cattle production were identified as risk factors associated with being classified as a case farm. With the categorised BTM ELISA result as the response variable, heifers grazing on wet pastures, dry cows grazing on wet pastures, and purchase of cows were identified as risk factors. Within the case and control groups, 74.8 and 12.7% of farms were positive for fasciolosis on BTM ELISA, respectively. The differences are likely to be related to the detection limit of the farm-level prevalence by the BTM ELISA test, time span between slaughter data and BTM, and the relatively low sensitivity of liver inspection at slaughter. Control of bovine fasciolosis in Denmark should target heifers and dry cows through grazing management and appropriate anthelmintic treatment, and BTM ELISA can be a useful diagnostic tool for fasciolosis in Danish dairy farms

    Phylogenetic relationships among Toxocara spp. and Toxascaris sp. from different regions of the world

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    Toxocara and Toxascaris are parasitic nematodes that infect canids and felids although species of the genus Toxocara also infect humans. This work aimed to establish the phylogenetic and phylogeographic relationship between specimens of T. canis, T. cati, T. malaysiensis and Toxascaris leonina and to evaluate the degree of host specificity. In total, 437 samples (adults and pools of eggs) were collected from canids and felids from eight countries. Parasites were identified by morphology, PCR linked Restriction Fragment Length Polymorphism (PCR-RFLP) and partial sequencing of the mitochondrial gene cox1. Phylogenetic trees were constructed and genetic distance among isolates was estimated. Based on the molecular characterization all worms were identified in agreement with their respective hosts with the exception of three samples; two from cats and one from dogs identified as T. canis and T. cati, respectively. There was no clear geographical clustering of the samples despite this study including parasites from three continents. This is the first study, to our knowledge, to use molecular methods to identify T. canis in cats and T. cati in dogs with host specificity being the most common finding. Our developed PCR-RFLP method was found to be a facile and reliable method for identifying Toxocara species.A91F-E8B8-FA62 | Teresa Susana Letra MateusN/
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