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The animal health and welfare status in European organic dairy production does not in all aspects meet the organic principles and consumers’ expectations and needs to be improved. To achieve this, tailored herd health planning, targeted to the specific situation of individual farms could be of use. The aim of this study was to apply herd health planning in a structured participatory approach, with impact matrix analysis, not previously used in this context, in European organic dairy farms and to assess changes in animal health and welfare. Herd health planning farm visits were conducted on 122 organic dairy farms in France, Germany and Sweden. The farmer, the herd veterinarian and/or an advisor took part in the farm discussions. The researcher served as facilitator. Baseline data on the animal health status of the individual farm, collected from national milk recording schemes, were presented as an input for the discussion. Thereafter a systematic impact matrix analysis was performed. This was to capture the complexity of individual farms with the aim to identify the farm-specific factors that could have a strong impact on animal health. The participants (i.e. farmer, veterinarian and advisor) jointly identified areas in need of improvement, taking the health status and the interconnected farm system components into account, and appropriate actions were jointly identified. The researcher took minutes during the discussions, and these were shared with the participants. No intervention was made by the researcher, and further actions were left with the participants. The number of actions per farm ranged from 0 to 22. The change in mortality, metabolic diseases, reproductive performance and udder health was assessed at two time points, and potential determinators of the change were evaluated with linear regression models. A significant association was seen between change in udder health, as measured by the somatic cell count, and country. At the first follow-up, a significant association was also found between change in the proportion of prolonged calving interval and the farmers’ desire to improve reproductive health as well as with an increase in herd size, but this was not seen at the second follow-up. The degree of implementation of the actions was good (median 67%, lower quartile 40%, upper quartile 83%). To conclude, the degree of implementation was quite high, improvement of animal health could not be linked to the herd health planning approach. However, the approach was highly appreciated by the participants and deserves further study.  相似文献   
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黄慰文 《人类学学报》1993,12(4):297-304
实践证明,Movius在本世纪40年代建立的东亚,东南亚旧石器分类体系有严重缺陷。经过厘定,目前在欧洲和非洲通用的吹斫器,手斧,薄刃斧,手镐,球状器和刮削器等分类概念,也适用于东亚,东南亚旧石器初期的重型工具工业。  相似文献   
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The effects of various medium sterilization conditions on fermentations of a recombinant, acidic fibroblast growth factor (aFGF) producing Escherichia coli have been studied. Changes in the medium resulting from sterilization were monitored by pH and absorption spectra. This simple experiment provided excellent data for the demonstration of the usefulness of comparative reasoning tools in order to evaluate the effect of sterilization on fermentation performance. The time profiles of the main parameters (e.g., carbon dioxide evolution rate, dissolved oxygen, pH, and aFGF productivity) were simplified into piecewise contiguous linear segments, each of which was sequentially numbered. The length, position, and slope of each tine were then characterized. Application of the comparative reasoning tools confirmed that separate sterilization of the glucose was necessary for the success of the process, despite adding to the cost and complexity. The comparative data analysis also showed that scaleup with longer sterilization holding and cooling times would not be detrimental to aFGF production. (c) 1995 John Wiley & Sons, Inc.  相似文献   
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Stone tools are the most durable and ubiquitous residue of prehistoric hominid activity. For this reason, archeologists attempt to learn as much as possible about hominid behavior from the analysis of lithic artifacts. Lithic microwear analysis reconstructs aspects of stone-tool use from patterned variation in the traces of microscopic wear on those tools. The analysis of lithic microwear traces has increased our understanding of how stone tools were used in contexts ranging from the early Pleistocene to the ethnographic present.  相似文献   
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以CasX为例简述新型CRISPR-Cas系统的基本属性和研究方法   总被引:1,自引:1,他引:0  
在细菌与古菌中广泛存在的CRISPR-Cas系统,作为目前发现的原核生物唯一的适应性免疫系统,抵御着病毒和质粒的入侵。自20世纪80年代首次被发现至今,CRISPR-Cas系统的基本情况逐渐清晰,包括名称缩写、分类、进化关系等方面。近年来,由于第二类CRISPR-Cas系统作为一种有潜力的基因编辑工具而逐渐成为应用研究被关注,对CRISPR-Cas系统的基础研究热度也持久不衰。为了使此类基因编辑工具在实际应用领域更加安全便捷,针对已发现的CRISPR-Cas系统在根据基础研究领域的成果进行优化的同时,对新型CRISPR-Cas系统的发掘工作也同等重要。本文以2017年发现的CasX为例,简要概述针对一种新发现的CRISPR-Cas系统需要研究确定的基本属性及相关研究方法。  相似文献   
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《L'Anthropologie》2021,125(2):102865
The huge asiatic area does not show clear cut traditions but only fundamental tendencies proper to the human mind considered in its whole evolution mechanism. These tendencies are both clear and powerful: lightness of the skulls, technical blanks lighter, bone tools, pendants, and high mobility. The cultural European categories cannot be applied as such since the anthropological units were fuzzy, just like the huge steppes where they have developed. Europe just represents marginal caricatures and fixed of these general movements acting like waves perpetual and powerful.  相似文献   
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Application of external organic inputs to soils can be considered as one of the most ancient strategies in agriculture, and it has been commonly used since the very beginning of human-based agricultural practices. During all this time, application of several organic matters to agricultural soils has demonstrated their benefit to plants and soils. Organic amendments have proved to be useful in recovering soil properties, improving soil quality and, in some cases, can be directly involved in providing beneficial effects to plants. All these obtained effects finally lead to an increase in crop protection and sustainability. One most expected effect caused by the application of organic amendments, is the suppression of a wide range of soilborne pathogens (mainly bacterial and fungal pathogens) due to the induction of physicochemical and biological changes in soils. In order to get insight into the nature of the induced soil suppression of soilborne plant pathogens, the analysis of the physical, chemical and the microbial changes, pointed to the key role of beneficial activities produced by soil microorganisms finally adapted to the environmental changes produced by the influence of organic amendments. As shown in the case studies reported here, participation of soil microbes specifically selected after organic amendment is crucial in the control of fungal soilborne diseases. Moreover, the development of “omics” approaches allowed these recent studies to go one step further, revealing the main actors involved in the induced soil suppressiveness and their activities. Thus “omics” techniques will help to understand the soil and its microbiome as a whole system, and to assign the important roles of its biological components.  相似文献   
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The present study tested two diver-operated rotating brush systems, coupled with suction and collection capabilities, to determine their efficacy in the management of vessel biofouling. Both rotating brush systems proved effective (>80%) in removing low-to-moderate levels of fouling from flat and curved experimental surfaces (Perspex plates). However, performance was generally poorer at removing more advanced levels of fouling. In particular, mature calcareous organisms were relatively resistant to the rotating brushes, with a high proportion (up to 50%) remaining on plates following treatment. On average, >95% of defouled material was collected and retained by both systems. The amount of lost material generally increased when treating curved plates with increasing biomass, whereas the material lost from flat plates was typically less and remained relatively constant throughout the trials. The majority (>80%) of fouling not captured by the systems was crushed by the brushes (ie non-viable). However, a diverse range of viable organisms (eg barnacles and hydroids) was lost to the environment during the defouling trials. When defouling a vessel, unintentional detachment of fouling organisms is likely to be high through physical disturbance by divers operating the devices and by associated equipment (eg hoses). Furthermore, residual biosecurity risks are also likely to remain due to diver error, persistent fouling remaining on treated surfaces and the inaccessibility of niche areas to the brush systems. To address these limitations, further research into alternative treatment methods is required.  相似文献   
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