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91.
92.
Shared activities are known to create a good relationship between dog and man. Therefore, it can be expected that animals working in harness with their handlers, such as search and rescue dogs, show a higher attachment to man.The aim of the current research was to assess whether there are differences between pet and working dogs in the attachment to owners/handlers.Forty dogs were involved, 26 pets and 14 search and rescue dogs (taken home when not working). Their attachment to owners/handlers was analyzed by using a modified version of the Ainsworth Strange Situation Test and a recall test, while owners and handlers filled in a questionnaire and were scored on the Lexington Attachment to Pets Scale.Statistical analysis revealed no statistically significant differences between pet and working dogs for behaviors indicating an attachment bond: behavior oriented to door/chair/shoe during the absence of owner/handler (which represents “search of absent person”; U = 132.000, P = 0.156), contact with/proximity to owner/handler (i.e., “contact maintenance effect”; U = 157.000, P = 0.478), whining during owner's/handler's absence (“protest at the separation”; U = 147.000, P = 0.288), and individual play (U = 146.000, P = 0.288) and exploration (U = 138.500, P = 0.215) in presence of owner/handler, representing the “secure base effect.”Despite the lack of statistical differences, the formulated hypothesis may be not completely rejected, as a trend of a higher attachment in search and rescue dogs existed. It can be concluded that in carefully owned dogs, the level of attachment is increased by working as a search and rescue dog, but the difference does not lead to statistically relevant results.  相似文献   
93.
OBJECTIVE: To determine the effects of various vehicles on the penetration and retention of hydrocortisone applied to canine skin. SAMPLE POPULATION: 20 canine skin samples obtained from the thorax, neck, and groin regions of 5 Greyhounds. PROCEDURE: Skin was harvested from dogs after euthanasia and stored at -20 degrees C until required.The skin was then defrosted and placed into diffusion cells, which were maintained at approximately 32 degrees C by a water bath. Saturated solutions of hydrocortisone that contained trace amounts of radiolabelled [14C]-hydrocortisone in each vehicle (ie, PBS solution [PBSS] alone, 50% ethanol [EtOH] in PBSS [wt/wt], and 50% propylene glycol in PBSS [wt/wt]) were applied to the outer (stratum corneum) surface of each skin sample, and aliquots of receptor fluid were collected for 24 hours and analyzed for hydrocortisone. RESULTS: The maximum flux of hydrocortisone was significantly higher for all sites when dissolved in a vehicle containing 50% EtOH, compared with PBSS alone or 50% propylene glycol, with differences more prominent in skin from the neck region. In contrast, higher residues of hydrocortisone were found remaining within the skin when PBSS alone was used as a vehicle, particularly in skin from the thorax and neck. CONCLUSIONS AND CLINICAL RELEVANCE: Penetration of topically applied hydrocortisone is enhanced when EtOH is used in vehicle formulation. Significant regional differences (ie, among the thorax, neck, and groin areas) are also found in the transdermal penetration and skin retention of hydrocortisone. Variability in clinical response to hydrocortisone can be expected in relation to formulation design and site of application.  相似文献   
94.
OBJECTIVE: To investigate in vitro transdermal absorption of fentanyl from patches through skin samples obtained from various anatomic regions of dogs. SAMPLE POPULATION: Skin samples from 5 Greyhounds. PROCEDURE: Skin samples from the dogs' thoracic, neck, and groin regions were collected postmortem and frozen. After samples were thawed, circular sections were cut and placed in Franz-type diffusion cells in a water bath (32 degrees C). A commercial fentanyl patch, attached to an acetate strip with a circular hole, was applied to each skin sample. Cellulose strips were used as control membranes. Samples of receptor fluid in the diffusion cells were collected at intervals for 48 hours, and fentanyl concentrations were analyzed by use of high-performance liquid chromatography. RESULTS: Mean+/-SD release rate of fentanyl from the patch, defined by its absorption rate through the non-rate-limiting cellulose membrane, was linear during the first 8 hours (2.01+/-0.05 microg/cm2 of cellulose membrane/h) and then decreased. Fentanyl passed through skin from the groin region at a faster rate and with a significantly shorter lag time, compared with findings in neck or thoracic skin samples. CONCLUSIONS AND CLINICAL RELEVANCE: In vitro, fentanyl from a patch was absorbed more quickly and to a greater extent through skin collected from the groin region of dogs, compared with skin samples from the thoracic and neck regions. Placement of fentanyl patches in the groin region of dogs may decrease the lag time to achieve analgesia perioperatively; however, in vivo studies are necessary to confirm these findings.  相似文献   
95.
Patch-based landscape metrics can be biased by the boundaries and the extent of a reporting unit if the boundaries fragment patches. We call this the “boundary problem”. The effective mesh size m eff is a convenient method to quantify landscape fragmentation, that is based on the probability that two points chosen randomly in a region will be connected, e.g., not be separated by roads, railroads, or urban development. The cutting-out (CUT) procedure, used in the original computation of m eff, suffers from the boundary problem because the boundaries of the reporting units are considered to be additional barriers. Therefore, m eff will be underestimated, particularly if reporting units are embedded within the broader landscape. In this paper, we present a solution to overcome this limitation by a new method called “cross-boundary connections” (CBC) procedure. It attributes the connections between two points that are located in different reporting units to both reporting units. We systematically compare the CBC procedure to the CUT procedure and show that the boundary problem is intrinsic to the CUT procedure, while the CBC procedure is independent of the size and administrative boundaries of reporting units. In addition, we elucidate the superior performance of the new procedure in the case study of South Tyrol where m eff is being used for sustainability reporting on the level of municipalities. The new CBC procedure eliminates the bias due to the boundaries and the size of reporting units in measuring landscape fragmentation through m eff.  相似文献   
96.
97.
Nearly 40% of seafood is traded internationally and an even bigger proportion is affected by international trade, yet scholarship on marine fisheries has focused on global trends in stocks and catches, or on dynamics of individual fisheries, with limited attention to the link between individual fisheries, global trade and distant consumers. This paper examines the usefulness of fish price as a feedback signal to consumers about the state of fisheries and marine ecosystems. We suggest that the current nature of fisheries systems and global markets prevent transmission of such price signals from source fisheries to consumers. We propose several mechanisms that combine to weaken price signals, and present one example – the North Sea cod – to show how these mechanisms can be tested. The lack of a reliable price feedback to consumers represents a challenge for sustainable fisheries governance. We therefore propose three complimentary approaches to address the missing feedback: (i) strengthening information flow through improved traceability and visibility of individual fishers to consumers, (ii) capitalizing on the changing seafood trade structures and (iii) bypassing and complementing market mechanisms by directly targeting citizens and political actors regarding marine environmental issues through publicity and information campaigns. These strategies each have limitations and thus need to be pursued together to address the challenge of sustainability in global marine fisheries.  相似文献   
98.
Pomegranate (Punica granatum L.) fruits are used mainly by the juice industry, for which seeds are a by-product to be disposed of, though they could potentially be a source of bioactive compounds. In this work, germination (total germination percentage, G; mean germination time, MGT; time to reach 80% of germination, TG80; seedling shoot length, fresh weight and dry matter), and nutritional value (total phenolics, TP; total flavonoids, TF; total non-tannins, TNT; antioxidant activities) of pomegranate seeds and sprouts were determined on four commercial pomegranate cultivars (Akko, Dente di Cavallo, Mollar de Elche and Wonderful). Seeds were removed from ripe fruits and incubated in plastic trays containing sterile cotton wetted with distilled water. Sprout shoots were harvested when they reached the complete cotyledon expansion, i.e., the ready-to-eat stage. Akko showed the best germination performance (G = 98%; MGT = 14 days after sowing, DAS; TG80 = 16 DAS), followed by Mollar de Elche. Sprouting dramatically increased TP, TF, TNT and antioxidant activity in all genotypes, with the highest values recorded in Mollar de Elche and Dente di Cavallo. Overall, based on germination performance, Akko and Mollar de Elche would be the best cultivars for sprouting. Sprouting pomegranate seeds appears to be a suitable way of utilizing by-products of the juice industry to obtain bioactive compounds.  相似文献   
99.
The cultivation of cocoa has been an important driver of tropical deforestation globally. Efforts to reverse this trend are focusing on the reintroduction of shade trees to cocoa plantations. Shade trees are valuable in enhancing biophysical conditions on cocoa (Theobroma cacao) fields and contribute to biodiversity and product diversification for smallholder producers. Participatory trials of cocoa agroforests planted with indigenous shade tree species were undertaken with farmers in the Atwima District of the Ashanti Region of Ghana, to increase tree volume on cocoa fields while improving rural livelihoods and enhancing environmental sustainability. An ex ante financial analysis of the technology was undertaken to assess its economic viability. Input–output data were collected from farmer experiments over three seasons and supplemented with data from traditional cocoa fields of varying rotation ages, and secondary data on production in later years of an eighty-year cocoa rotation. A discounted cash flow analysis was carried out to estimate the benefit-cost (B/C) ratio, net present value (NPV), internal rate of return (IRR) and land expectation value (LEV) as well as the sensitivity to a 20% decline in cocoa prices and additional chemical costs for various shade scenarios at a 10% discount rate. It was observed that cocoa production is, in general, profitable. The change from the traditional system to one with hybrid cocoa raised the IRR from 31% to 57% with planted shade and 67% without, although extra agrochemical costs would tend to reduce the profitability of unshaded hybrid cocoa in particular. The age of maximum LEV for the various scenarios suggests that the optimum economic rotation for the hybrid cocoa is between 18 and 29 years, much less than the traditional system.  相似文献   
100.
Hot water having a minimum temperature of 55°C employed for at least ten minutes will kill all vermin on cacti—such as spider mites, mealy bugs, ground mealy bugs and root nematodes in all their stages of development. The hot water treatment is directed against mycoplasmalike organisms in cacti. TwoAustrocylindropuntia spp. cuttings of the same size were prepared. One was left untreated. The other was immersed for 12 minutes in hot water at 57°C and allowed to cool slowly down to 25°C. Sixteen months afterwards the cutting which was treated displayed a growth pattern different from the untreated one in that it exhibited a general pattern of growth like that of the cactusAustrocylindropuntia subulata. Its growth was characterized by the development of hairs and spines, intensive growth of thickness and formation of tubercles or protuberances. Moreover the leaflets were double so long as those in the untreated cutting and the feverish attempts to form new shoots were repressed. The untreated cutting displayed none of these characteristics.  相似文献   
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