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1.
Recent literature and public discourse emphasize the role of craft breweries in the revitalization process of economically distressed neighborhoods across the U.S. With this, many are reporting rising property values in areas surrounding craft breweries. This research examines the impacts of craft breweries on both residential and commercial property values in a case study of Charlotte, North Carolina. Estimating a series of hedonic models which incorporate a difference‐in‐difference estimator, we find that craft breweries have a positive impact on residential property values. While many areas in close proximity to a craft brewery appear to have been associated with relatively higher price premiums even before the opening of the brewery, breweries tend to add to this premium, especially in center‐city neighborhoods. We find no significant impacts on commercial property values. These results are informative to policy makers considering revising zoning laws and other regulations in efforts to promote the growth of craft breweries and spur economic development in their local economies. 相似文献
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A good correlation exists between specific neutralising antibody titre and protection against challenge with foot-and-mouth disease virus (FMDV) in infected or virus-vaccinated cattle, but not in the case of animals immunised with synthetic FMDV peptides. Therefore, mechanisms other than simple neutralisation are likely to be important in vivo. Antibody affinity may influence the protective capacity of sera from immunised animals and experiments were carried out to measure the functional affinity for synthetic FMDV peptide of sera from guinea pigs and cattle given various synthetic vaccines. In guinea pigs given a single dose of synthetic vaccine, antibody affinity increased with time after immunisation. In cattle, however, administration of a second dose of peptide 21 days after the first markedly retarded the process of affinity maturation. For guinea pig sera of equivalent neutralising activity, those of higher functional affinity had higher protective indices than those of lower functional affinity. Knowledge of the importance of antibody affinity in protection against FMD is important for an improved understanding of the mechanisms of protection and for the design of novel vaccines. 相似文献
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Details of the management, feeding, level of activity and routine health care of horses in Scotland and the five northernmost counties in England were recorded through a stratified random sample of horse owners who had responded to a previous survey. Sixty-eight per cent of the horses were kept where their owners resided, and 32 per cent were kept away from the owner's home. More than 99 per cent were turned out to grazing for at least part of the year and 81 per cent were stabled for at least part of the time, most commonly bedded on straw (50 per cent) or shavings (34 per cent). Hay was fed to 87 per cent, sugar beet pulp to 64 per cent and commercially prepared concentrate mixes to 60 per cent of the horses. Hacking was the most popular activity (52 per cent of horses) followed by riding/pony club events (28 per cent) and showing (21 per cent). The majority of the horses were involved in more than one activity. There were an estimated 0.88 veterinary visits per horse per year and 29 per cent of the horses were reported to suffer from at least one permanent or recurrent health disorder. The median annual numbers of administrations of vaccines (influenza and tetanus) and anthelmintics were one and seven respectively per horse, and each horse was shod a median seven times. There were significant differences in the management of horses kept in different types of premises and in areas of different human population density. 相似文献
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F. RODRÍGUEZ G. A. RAMÍREZ A. S. RAMÍREZ H. J. BALL A. ESPINOSA
DE LOS MONTEROS A. FERNNDEZ 《Zoonoses and public health》2002,49(5):226-229
Samples from the mammary tissue of 14 lactating goats (12 naturally infected and two experimentally infected) were examined for the presence of Mycoplasma agalactiae. A monoclonal antibody (5G12) was applied to formalin‐fixed, paraffin‐wax‐embedded sections and labelled by the avidin–biotin peroxidase complex (ABC) method. Histological examination of tissue sections revealed strong immunoreactivity in all animals included in the study. Mycoplasma agalactiae antigen was mainly detected in the cellular debris at the periphery of purulent exudates present within lactiferous sinuses, and lactiferous and interlobular ducts. In addition, M. agalactiae organisms appeared in the cytoplasm of the epithelium of ducts, and in infiltrating macrophages and neutrophils within the ducts, alveoli, interstitial tissue and regional lymph node sinuses. It is concluded that this monoclonal antibody‐based immunohistochemical technique is an efficient and specific method for the post‐mortem detection of M. agalactiae in cases of clinical mastitis as well as being a useful tool for the study of the route of infection and cellular types involved during mastitis caused by this organism. 相似文献
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Jacqueline Reid 《British poultry science》1983,24(2):233-235
1. In order to study the mammillary layer of the avian egg shell by scanning electron microscopy, it is necessary to separate the outer shell membrane from the calcified shell.
2. Chemical methods of effecting membrane removal are difficult to standardise due to variations in the strength of the membrane‐shell bond.
3. The use of reactive gas plasma provides an alternative, more efficient method for removing membranes without the risk of damage to underlying crystalline structures. 相似文献