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Capture fisheries in the north‐east Atlantic account for approximately 10% of all fish consumed from capture fisheries globally. The literature shows that consumers show considerable interest in social sustainability of products in general and of fish specifically. This interest, however, has not yet been investigated for fish from the north‐east Atlantic. The first objective of this study, therefore, was to investigate whether consumers are interested in social sustainability issues of whitefish from the north‐east Atlantic by determining preferences for four social sustainability issues with distinct benefits in relation to a known reference point (i.e. approach to overfishing). The second objective of this study was to determine to what degree case‐specific and general psychographic consumer characteristics explain preferences for these issues. Choice modelling results from an online survey among 457 Dutch consumers show that consumers have the strongest preference for the environmental sustainability issue approach to overfishing. In addition, results on the social sustainability issues showed that consumers prefer fish welfare over product quality, worker safety and local employment, indicating that in this case, consumers place animal benefits over personal, worker and community benefits. The case‐specific psychographic characteristic concern contributed most to explaining preferences for the environmental sustainability issue, whereas the general psychographic characteristic personal relevance contributed most to explaining preferences for the social sustainability issues. This result is likely explained by the principal focus on MSC certification in markets for fish products, which caused consumers to form opinions (e.g. concern) on overfishing, but not on social sustainability.  相似文献   
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While the pathogenesis of chronic valvular disease (CVD) in dogs remains unclear, alterations in the activity of specific metalloproteinase enzymes and their inhibitors within the valve stroma are suspected of having a role. This study describes the immunohistochemical distribution pattern of matrix metalloproteinase (MMP) types 2, 9 and 14 and their tissue inhibitors, termed tissue inhibitors of metalloproteinase (TIMP), types 2 and 3, in normal canine mitral valves (MVs) (n=10) and in dogs with mild (n=7), moderate (n=14) and severe (n=9) CVD. In normal MVs, MMP-2 and -14, and TIMP-2 were expressed in isolated stromal cells. Tissue inhibitor of metalloproteinase-3 exhibited moderate intracellular and mild extracellular expression. With increasing severity of CVD, the expression of MMP-2 decreased. The number of stromal cells expressing MMP-14 increased, predominantly in the margins of the nodular lesions. Tissue inhibitor of metalloproteinase-2 and -3 expression increased both intra- and extracellularly. Matrix metalloproteinase-9 was not detected in normal or diseased valves. In conclusion, CVD was characterised by alterations in the distribution and intensity of valvular MMP and TIMP expression, suggesting that depressed catabolism and the accumulation of extracellular matrix components within affected valves contributes to their structural alteration and consequent loss of function.  相似文献   
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In recent foot and mouth disease outbreaks, many healthy animals have been culled to prevent disease transmission. Emergency vaccination is discussed as an alternative to culling of unaffected animals. A spatial and temporal Monte–Carlo simulation model was used to compare preventive culling and emergency vaccination. Different outbreaks are described using additional influence factors such as airborne spread, farm density, type of index-case farm and delay until establishment of the control strategies. The fewest farms were infected establishing a combined strategy including a 1 km preventive culling and 1–10 km emergency vaccination zone around each outbreak farm. Taking the number of culled and vaccinated farms into account, vaccination around the first diagnosed farm combined with the baseline strategy (culling of outbreak farms, protection and surveillance zone, contact tracing) is to be preferred. In the present study, emergency vaccination was an effective control strategy especially in densely populated regions.  相似文献   
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The rings of Uranus are oriented edge-on to Earth in 2007 for the first time since their 1977 discovery. This event provides a rare opportunity to observe their dark (unlit) side, where dense rings darken to near invisibility, but faint rings become much brighter. We present a ground-based infrared image of the unlit side of the rings that shows that the system has changed dramatically since previous views. A broad cloud of faint material permeates the system but is not correlated with the well-known narrow rings or with the embedded dust belts imaged by the Voyager spacecraft. Although some differences can be explained by the unusual viewing angle, we conclude that the dust distribution within the system has changed substantially since the 1986 Voyager encounter and that it occurs on much larger scales than has been seen in other planetary systems.  相似文献   
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The hypotheses of this prospective study were that (1) left atrial appendage (LAA) blood flow velocities can be recorded in cats with myocardial disease by transthoracic Doppler echocardiography, (2) LA enlargement, LA mechanical dysfunction, and left ventricular (LV) diastolic abnormalities are associated with decreased LAA flow velocities, and (3) low LAA flow velocities predict the appearance of spontaneous echocardiographic contrast in cats with cardiomyopathy. Transthoracic 2-dimensional, M-mode, and Doppler echocardiographic studies were performed in 89 cats with hypertrophic, restrictive, dilated, or unclassified cardiomyopathy or with hyperthyroid heart disease. Maximal LAA flow velocity (LAAmax) was decreased (P < .001) in cats with cardiomyopathy (median, 0.28 m/s; range, 0.08-1.35) compared to normal cats. Associated with decreased LAA flow velocities were increased LA size, decreased LA function, increased severity of LV diastolic dysfunction, and the presence of congestive heart failure. Multivariate logistic regression analysis detected an LAAmax <0.20 m/s as the only independent variable to predict LA spontaneous echocardiographic contrast (odds ratio, 30.1; 95% confidence interval [CI], 4.1 222.3; P < .001). Receiver operating characteristic analysis performed to predict spontaneous echocardiographic contrast indicated an area under the curve of 0.88 (95% CI, 0.80-0.95; P < .001) with sensitivities of 100 and 74% and specificities of 69 and 83% for LAAmax <0.25 and <0.20 m/s, respectively. Thus, low LAA flow velocities identified a subgroup of patients at increased risk of spontaneous echocardiographic contrast and possible thromboembolism. These findings may have important clinical implications for anticoagulation therapy and prognostication in cats with cardiomyopathy.  相似文献   
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This case report demonstrates the development and management of an osseous cyst-like lesion in the spongiosa of the navicular bone in a high-level show jumper with chronic intermittent forelimb lameness. The first evidence of navicular bone pathology was increased signal intensity on fat-suppressed images in the medulla of the right navicular bone, which progressed to a cystic lucency identified on radiographs at 24 months. The horse's progress was documented over a period of 2 years and 2 months, including lameness investigation, treatment, radiographs, and six follow-up standing low-field magnetic resonance imagings. At the last clinical recheck, the horse showed no signs of lameness and continued to compete in show jumping at an international level event.  相似文献   
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