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1.
Gurler AM 《Journal of veterinary medical education》2007,34(5):633-638
Veterinary medical education in Turkey began in 1842 and is now offered by 17 universities. Since 1895, topics related to animal welfare have been covered as part of the curriculum in courses titled Deontology, Health Inspection, and Laws of Veterinary Medicine. During the 2004/2005 academic year, for the first time, animal welfare was included as a separate course as part of the curriculum in two veterinary faculties. As a result of curriculum adjustment efforts at both national and international levels, the animal-welfare course is now expected to be required for all veterinary students in Turkey. This study reports on the development of animal-welfare curricula in veterinary medical education in Turkey and describes the historical events from which the appreciation of it arose. 相似文献
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Transmissible venereal tumour (TVT) is a rare vaginal tumour that can be treated surgically or cryosurgically as well as by radiotherapy or chemotherapy. Vincristine has been found to be very effective for treating TVT. Since vaginal secretion or discharge may contain neoplastic cells, the cytological identification of TVT cells is possible. The present study was carried out in 12 bitches. Vaginal smears were obtained with cotton swab from the anterior vagina and TVT suspected structures. The smears were stained according to Papanicolaou and assessed by light microscopy. Additionally the general condition of the patients was evaluated by haematological and radiographic examinations. In bitches with TVT vincristine sulphate was administered intravenously at weekly intervals. The total treatment period was three to six weeks until no atypical cells were found in the smear. This was the case after an average of 3.2 +/- 1.3 applications. Tumour masses became smaller and by this non-visible from the rima vulva after 4.2 +/- 0.7 applications. During the treatment, two of the 12 bitches (16.7%) suffered from vomiting and diarrhoea while three (25%) showed neutropenia. Twelve months after completion of treatment, the bitches were examined again and vaginal smears were taken in order to control the recovery process or a possible recurrence of TVT. No atypical cells were found in any vaginal smear. By this exfoliative cytology has proved to be a safe and easy method for TVT diagnosis and for observing the recovery process. 相似文献
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Suat Irmak Jose O. Payero Ayse Kilic Lameck O. Odhiambo Daran Rudnick Vivek Sharma David Billesbach 《Irrigation Science》2014,32(6):471-483
We investigated the magnitude and dynamics of the eddy covariance system (ECS) residual energy (energy balance closure error) for a subsurface drip-irrigated maize (Zea mays L.) field in 2005 and 2006 growing and non-growing (dormant) seasons. The corrections for coordinate rotation, oxygen, frequency, and Webb–Pearman–Leuning corrections improved the slope of the total convective energy (latent heat + sensible heat) with respect to the net available energy (from 0.68 to 0.84), but the data filtering (for horizontal and frictional wind speeds higher than 2 m s?1 and lower than 0.2 m s?1) had little effect on the slope. Also, the number of data points available for the analyses was reduced by 53 % after filtering. Overall, the daytime residual energy varied between ?100 and 200 W m?2 during the dormant seasons and between ?500 and 600 W m?2 during the growing seasons. Most of the nighttime residual energy ranged within ±40 W m?2 during the calendar year in 2005 and within ?60 and 20 W m?2 in 2006. During nighttime, the total convective energy is vertically distributed with respect to (R n ? G), indicating that the total convective energy is independent of the variations in (R n ? G). Secondly, it was observed that nighttime residual energy did not show any seasonal variation patterns throughout the two consecutive years and confined mostly within a narrow range of ±40 W m?2, showing no dependency on seasonal changes in surface conditions. The maximum variation in residual energy was usually around frictional wind speed of 0.3–0.5 m s?1 (varying between ?150 and 300 W m?2) and then decreasing to a range of ±100 W m?2 at higher frictional wind speeds. On average, the residual energy decreased by about 33 W m?2 (after the intercept) for every 1.0 m s?1 increase in frictional wind speed, whereas the residual energy decreased by about 4 W m?2 (after the intercept) for every 1.0 m s?1 increase in horizontal wind speed. Similar diurnal residual energy distribution patterns, with different magnitudes, were observed during growing and dormant seasons. Even though a slight decrease in residual energy was observed with increase in leaf area index (LAI) in both growing seasons, LAI did not have considerable influence on the seasonal variation in the residual energy. The residual energy was also evaluated by separating the data into morning and afternoon hours. We observed that the root-mean-squared difference value is slightly greater for the morning data than the afternoon, indicating greater residual energy in the morning hours due to weaker turbulent mixing than the afternoon. Overall, significant reduction in the available evapotranspiration data after applying a series of corrections possess challenges in terms of utilization of ECS for in-season irrigation management and crop water requirement determinations that needs to be further researched and addressed. 相似文献
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Nathan?C.?HealeyEmail author Ayse?Irmak Timothy?J.?Arkebauer David?P.?Billesbach John?D.?Lenters Kenneth?G.?Hubbard Richard?G.?Allen Jeppe?Kjaersgaard 《Irrigation and Drainage Systems》2011,25(3):151-178
Water consumed through evapotranspiration (ET) impacts local and regional hydrologic regimes on various spatial and temporal
scales. Estimating ET in the Great Plains is a prerequisite for effective regional water resource management of the Ogallala
(High Plains) Aquifer, which supplies vital water resources in the form of irrigation for extensive agricultural production.
The Sand Hills region of Nebraska is one of the largest grass-stabilized eolian (windblown) sand dune formations in the world,
with an area of roughly 50,000–60,000 km2 that supports a system of five major land cover types: (1) lakes, (2) wetlands (with lakes, ~5%), (3) subirrigated meadows
(water table is within ~1 m of surface; ~10%), (4) dry valleys (water table is 1–10 m below surface; ~20%), and (5) upland
dunes (water table is more than 10 m below surface; ~65%). Fully understanding the hydrologic regime of these different ecosystems
is a fundamental challenge in regional water resource assessment. The surface energy and water balances were analyzed using
Bowen Ratio Energy Balance Systems (BREBS) at three locations: (1) a meadow, (2) a valley, and (3) an upland dune. Measurement
of the energy budget by BREBS, in concert with Landsat remote sensing image processing for 2004 reveals strong spatial gradients
between sites in latent heat flux that are associated with undulating topographic relief. We find that daily estimates of
ET from BREBS measurements and remote sensing agree well, with an uncertainty within 1 mm, which is encouraging when applying
remote sensing results across such a broad spatial scale and undulating topography. 相似文献
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Graph theoretic approaches have received increased interest recently in landscape planning and conservation in the terrestrial realm, because these approaches facilitate the effective modelling of connectivity among habitats. We examined whether basic principles of graph theory can be extended to other ecosystems. Specifically, we demonstrate how a network-based context can be used for enhancing the more effective conservation of riverine systems. We first show how to use graph theoretic techniques to model riverscapes at the segment level. Then we use a real stream network (Zagyva river basin, Hungary) to examine the topological importance of segments in maintaining riverscape connectivity, using betweenness centrality, a commonly used network measure. Using the undirected graph model of this riverscape, we then prioritize segments for conservation purpose. We examine the value of each of the 93 segments present in the Zagyva river basin by considering the conservation value of local fish assemblages, connectivity and the size of the habitat patches. For this purpose we use the ‘integral index of connectivity’, a recently advocated habitat availability index. Based on the results the selection of the most valuable habitat segments can be optimized depending on conservation resources. Because of their inherent advantage in the consideration of connectivity relationships, we suggest that network analyses offer a simple, yet effective tool for searching for key segments (or junctions) in riverscapes for conservation and environmental management. Further, although the joint consideration of aquatic and terrestrial networks is challenging, the extension of network analyses to freshwater systems may facilitate the more effective selection of priority areas for conservation in continental areas. 相似文献
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利用木麻黄营造沿海沙地防护林,不仅符合适地适树的造林原则,而且也是保护和恢复全省海防林带生态工程的有效途径之一.因此持续性发展木麻黄沿海防护林、苗木品种和造林技术至关重要.文章介绍了木麻黄沿海防护林造林技术,并对以后的造林工作提出了一些建议. 相似文献
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Forest loss with accompanying urbanization is often permanent as forests are replaced by impervious concrete structures or surfaces. The remaining forest patches are usually isolated and too small to maintain viable populations of forest-dependent wildlife species. Consistent with the species-area function (S = cAz), extirpation of species should follow forest loss. However, this has rarely ever been tested in the urban landscape. We determined whether the observed number of forest-dependent bird extirpations occurring after forest loss matches that predicted by the species-area function in Vancouver (study area ∼126.7 km2), British Columbia, Canada. Prior to European settlement in 1859, Vancouver was covered completely by coastal western hemlock forest. Based on published historical maps of forest cover and present Landsat imagery of Vancouver, we estimated that approximately 87% of the forest area in Vancouver has been converted to urban development. Using the species-area function, we then predicted that approximately 14 bird species closely associated with lowland forest should have been extirpated. This figure is significantly greater than the three bird species known to have been extirpated in Vancouver. When we constrained the comparison to bird species closely associated with lowland forest and restricted in their distribution in British Columbia, we found a close match between the observed and predicted number of extirpations, suggesting that bird species closely associated with lowland forest and restricted in their geographic distribution are most prone to extirpation as a result of forest loss. Given that urban areas are situated in productive habitats with inherently high species richness, it is important that local land-use plans incorporate the conservation of habitat fragments from the onset and place particular emphasis on the regionally restricted forest-dependent species. 相似文献