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111.
Food production, water management, land use, and animal and public health are all topics of extensive public debate. These themes are linked to the core activities of the agricultural sector, and more specifically to the work of farmers. Nonetheless, the ethical discussions are mostly initiated by interest groups in society rather than by farmers. At least in Europe, consumer organizations and animal welfare and environmental organizations are more present in the public debate than farmers. This is not how it should be. First, because consumers often cannot but rely on agriculture. Second, because recent research shows that farmers have moral beliefs and convictions that appear to be broader than economic considerations and that are—to a certain extent—specific to their profession. This raises the question how to make input from farmers operational in the public debates on the future of farming. We discuss one option: entrusting farmers with professional autonomy concerning moral matters related to farming. We sketch the historical background of the current situation in which farmers are relatively silent on moral matters and we present some clear indications that farmers have values and moral beliefs that are relevant for the public debate. Next the concepts of professionalism and professional autonomy are discussed and applied to the practice of farming. Finally, we discuss the relevance and limits of professional moral autonomy for the agricultural profession. We close with an overview of what this moral autonomy implies for and requires from farmers in practice. We conclude that if some preconditions are met by farmers, then this type of moral autonomy can be relevant for farmers and for society, and contributes to the quality of the public debate on the future of farming.  相似文献   
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Harmonizing coastal fisheries with water-quality improvement has become an essential factor for the sustainable use of coastal ecosystem services. Here, we present the scope of our study based on an interdisciplinary approach including ecological actions, socio-economic actions and socio-psychological actions. We chose to focus on the interaction between oyster aquaculture and seagrass vegetation as a typical ecological action using the coastal ecosystem complex (CEC) concept. Coastal organisms have adapted their traits to the environment over a long period of time, so that restoration of the CEC represents reconstruction of the original process of coastal production. Subtidal seagrass vegetation with intertidal oyster reefs is the original CEC in Japan, which would be expected to enhance coastal production by improving the production efficiency without adding nutrients. A simple field experiment examining carbon and nitrogen contents and stable isotope ratios revealed that oyster spats cultivated on a tidal flat adjacent to seagrass beds had higher nitrogen contents and higher δ13C ratios than spats cultivated in an offshore area using only pelagic production. This result suggests that utilization of the CEC, which enables oysters to use both pelagic and benthic production, has potential to sustain a food provisioning service for humans, even in oligotrophic conditions.  相似文献   
114.
Electroretinogram (ERG) and visual-evoked potentials (VEPs) are used in veterinary ophthalmology to assess the functional integrity of the retina and the central visual pathway. The interpretation of altered electrophysiologic potentials in diseases can be of great diagnostic value, although it is important to be aware of technical factors and the limitations of these techniques which may result in over-interpretation and misinterpretation of the recordings, such that they are similar to those found in disease-related electrophysiologic changes. The recorded potentials represent the differences in voltage between the active and reference electrodes. The ground electrode serves as zero. A differential or instrumentation amplifier selectively amplifies signals of interest while rejecting noise. Differences between inputs are amplified, whereas common signals are rejected in a process called common mode rejection (CMR). In order for CMR to be most effective in reducing noise, the electrode impedances should be balanced. Filters are part of the differential amplifier as they remove unwanted noise of a certain frequency. The frequency bandwidth, or passband, is the range of frequencies between low- and high-frequency filter settings that are not filtered out. Major sources of noise that cause interpretation artifacts are power lines, amplifier noise, physiologic activity, electrochemical electrode noise and circular grounds. Noise reduction is achieved with high amplifier input impedance, balanced electrode impedances, CMR, filters and signal averaging. Maintaining electrodes in good condition, achieving proper contact between electrode and animal, and keeping electrode leads short aid in achieving noise reduction.  相似文献   
115.
A new phenomenon of proliferation and branching of cotton has spread through most of the cotton growing areas in Israel in the past few years. Aphids, green leafhoppers and mites were ruled out as possible causal agents of branching. Leaf damage and bud destruction, similar to those observed in the field, were obtained by prolonged feeding of a laboratory-bred population ofThrips tabaci Lindeman on cotton seedlings. The feeding thrips were kept in a growth chamber at the temperatures and light conditions which prevail in April. The damage caused byT. tabaci in Israel is very similar to that described for several species of thrips, includingT. tabaci, in other countries. Yield of fiber and seed was significantly reduced in plants when branching occurred early (up to the beginning of June) but not late in the growing season.  相似文献   
116.
Increasing fruit load (from no berries present to 25, 50 and 100% of the initial fruit load) significantly decreased branch growth on 5-year-old coffee (Coffea arabica L.) trees of the dwarf cultivar 'Costa Rica 95', during their third production cycle. Ring-barking the branches further reduced their growth. Berry dry mass at harvest was significantly reduced by increasing fruit load. Dry matter allocation to berries was four times that allocated to branch growth during the cycle. Branch dieback and berry drop were significantly higher at greater fruit loads. This illustrates the importance of berry sink strength and indicates that there is competition for carbohydrates between berries and shoots and also among berries. Leaf net photosynthesis (P(n)) increased with increasing fruit load. Furthermore, leaves of non-isolated branches bearing full fruit load achieved three times higher P(n) than leaves of isolated (ring-barked) branches without berries, indicating strong relief of leaf P(n) inhibition by carbohydrate demand from berries and other parts of the coffee tree when excess photoassimilates could be exported. Leaf P(n) was significantly higher in the morning than later during the day. This reduction in leaf P(n) is generally attributed to stomatal closure in response to high irradiance, temperature and vapor pressure deficit in the middle of the day; however, it could also be a feedback effect of reserves accumulating during the morning when climatic conditions for leaf P(n) were optimal, because increased leaf mass ratio was observed in leaves of ring-barked branches with low or no fruit loads. Rates of CO(2) emission by berries decreased and calculated photosynthetic rates of berries increased with increasing photosynthetic photon flux (PPF) especially at low PPFs (0 to 100 micromol m(-2) s(-1)). The photosynthetic contribution of berries at the bean-filling stage was estimated to be about 30% of their daily respiration costs and 12% of their total carbon requirements at PPF values commonly experienced in the field (200 to 500 micromol m(-2) s(-1)).  相似文献   
117.
One hundred Norway spruce (Picea abies (L.) Karst.) clones (three ramets per clone) were analyzed for phloem phenol composition and concentration before and 10 days after wound inoculation with sterile malt agar. Fifty clones (Experiment 1) belonged to the same provenance, whereas the remaining clones (Experiment 2) belonged to five provenances from three geographic areas. In Experiment 2, two additional ramets from the same clones were mass inoculated with Ceratocystis polonica (Siem.) C. Moreau to quantify the resistance of each clone. Tree response to wound inoculations was characterized by increased catechin concentration in both experiments, accompanied by increases in astringin and decreases in piceid in Experiment 1. In both experiments, we observed a diverse group of phenolic compounds whose concentrations increased (catechin, astringin) or did not vary (taxifolin glucoside) in response to wound inoculations, whereas concentrations of a homogeneous group of stilbene compounds decreased (piceid) or did not vary (isorhapontin, unidentified stilbene). In Experiment 2, provenances from the alpine and Hercynian-Carpatic areas differed from provenances from the Baltic area with respect to the relative importance of these two groups of compounds, further indicating that the two groupings of phenolic compounds structure the Norway spruce populations. Eighty days after mass inoculation, the percentage of healthy sapwood, which was taken as a measure of tree resistance, indicated that clones from the Baltic area were less resistant to mass inoculations than clones from the alpine and Hercynian-Carpatic areas. We conclude that the degree of resistance of Norway spruce trees to mass inoculations with a bark beetle-associated fungus can be predicted based on the diversity of constitutive phloem phenols and the ability to induce phenol synthesis in response to wounding.  相似文献   
118.
The feasibility of ERS SAR Tandem data for mapping forest and non-forest cover in China was evaluated over Zengcheng County in the South China. An accuracy of 75% has been achieved. Then, the MACFERST (Mapping China Forest with ERS SAR Tandem data) project started by the Ministry of Science and Technology (MOST) of China and the European Space Agency (ESA) in 1999. The generation of a large-scale forest map requires solving problems such as the georeferencing and mosaicking of very long image strips covering huge regions and the adaptation of the classification algorithm to account for radiometric differences. Approaches to solve these problems and the classification results in the Northeastern of China will be presented in this paper.  相似文献   
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Degenerative osteoarthropathy resulting in a reduced active lifespan was observed in Ardenner horses. In the context of joint biology, insulin-like growth factor I (IGF-I) is a potential candidate to affect the anabolism of cartilage matrix molecules. A group of 30 Ardenner horses reared under standardized conditions from weaning were evaluated periodically from 15 to 28 months of age to detect the early manifestations of the disease. At the end of this period, horses were classified in two pathological groups related to the degree of interphalangeal degenerative osteoarthropathy based on clinical and radiographic evaluations: healthy (46.7%) and pathological (53.3%) horses. Seven sequential blood samples were taken from each horse (during the evaluation period) to study the variation of IGF-I plasma concentration. We tested the variations of the IGF-I plasma concentration during growth, and the effect of sex and of pathological classes. Significant variations were observed during the research period, with a maximum value corresponding to spring and a minimum in autumn. A significant reduction of the IGF-I plasma concentration was also observed in the pathological horses (433.5 +/- 19.5 ng/ml) compared to the healthy horses (493.9 +/- 18.2 ng/ml). An alteration in the level of this growth factor could induce a disregulation of the mechanisms involved in the local control of joint and bone tissue development.  相似文献   
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