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排序方式: 共有542条查询结果,搜索用时 15 毫秒
1.
Johannes Trini Hans Peter Maurer Sigrid Weissmann Tobias Würschum 《Plant Breeding》2020,139(5):906-915
Accurate hybrid prediction and knowledge about the relative contribution of general (GCA) and specific combining ability (SCA) are of utmost importance for efficient hybrid breeding. We therefore evaluated 91 triticale single-cross hybrids in field trials at seven environments for plant height, heading time, fresh biomass, dry matter content and dry biomass. Fresh and dry biomass showed the highest proportion (23%) of variance due to SCA. Prediction accuracies based on GCA were slightly higher than based on mid-parent values. Utilizing parental kinship information yielded the highest prediction accuracies when both parental lines have been tested in other hybrid combinations, but still moderate-to-low prediction accuracies for two untested parents. Thus, hybrid prediction for biomass traits in triticale is currently promising based on mid-parent values as emphasized by our simulation study, but can be expected to shift to GCA-based prediction with an increasing importance of GCA due to selection in hybrid breeding. Moreover, the performance of potential hybrids between newly developed lines can be predicted with moderate accuracy using genomic relationship information. 相似文献
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Stephanie A Smith Anthony H Tobias 《Veterinary Clinics of North America: Small Animal Practice》2004,34(5):1245-1271
ATE remains a devastating complication of cardiac disease. Despite some improvements in our understanding of the underlying causes and clinical features of this disease, short-term management remains a challenge, and mortality is high. Long-term mortality is primarily attributable to the severe underlying cardiac disease. Many questions remain to be answered regarding the ideal management approach for feline ATE. The authors' preferred diagnostic and therapeutic approaches for these difficult patients are detailed in Box. 1. 相似文献
4.
Maria Garcia-Martin Nora Fagerholm Claudia Bieling Dimitris Gounaridis Thanasis Kizos Anu Printsmann Matthias Müller Juraj Lieskovský Tobias Plieninger 《Landscape Ecology》2017,32(11):2133-2150
Context
Human–nature interactions are reflected in the values people assign to landscapes. These values shape our understanding and actions as landscape co-creators, and need to be taken into account to achieve an integrated management of the landscape that involves civil society.Objectives
The aim of this research was to increase the current knowledge on the most and least common landscape values perceived by local stakeholders, the patterns in the spatial distribution of values, and their connection to different socio-economic backgrounds and landscape characteristics across Europe.Methods
The research consisted of a cross-site comparison study on how landscape values are perceived in six areas of Europe using Public Participation GIS surveys. Answers were analysed combining contingency tables, spatial autocorrelation and bivariate correlation methods, kernel densities, land cover ratios, and viewshed analyses. Results were discussed in the light of findings derived from other European participatory mapping studies.Results
We identified shared patterns in the perception of landscape values across Europe. Recreation, aesthetics, and social fulfilment were the most common values. Landscape values showed common spatial patterns mainly related to accessibility and the presence of water, settlements, and cultural heritage. However, respondents in each study site had their own preferences connected to the intrinsic characteristics of the local landscape and culture.Conclusions
The results encourage land planners and researchers to approach landscape values in relation to socio-cultural and bio-physical land characteristics comprehensibly, acknowledging the complexity in the relationship between people’s perception and the landscape, to foster more effective and inclusive landscape management strategies.5.
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Tobias Schwarz MA Dr. Med. Vet. Martin Sullivan BVMS PhD Klaus Hartung Prof. Dr. Med. Vet 《Veterinary radiology & ultrasound》2000,41(3):220-225
The radiographic appearance of the cribriform plate was investigated in 16 canine cadaver heads. The cribriform plate appeared as a "V"-shaped multilinear bone-opaque stripe in the caudal nasal region in projections perpendicular to the hard palate in 6 dogs with a skull index between 50.00 and 54.00. In 9 dogs with a skull index between 55.40 and 74.40, the cribriform plate had a more "C"-shaped and sharp appearance. In vertically oblique projections with an obliquity greater than 20 degrees, the cribriform plate lost its sharp outline and finally (40 degrees) disappeared. In lateral projections the cribriform plate appeared as a "C"-shaped interrupted bone-opaque stripe in all 16 dogs. In more brachycephalic dogs frontal bone structures superimposed on the cribriform plate on ventrodorsal and dorsoventral views and accentuated the radiographic appearance of the plate. Vertically oblique views separated both structures to produce two lines. 相似文献
8.
Tobias Plieninger 《Landscape Ecology》2006,21(1):91-105
Mediterranean agroforestry landscapes, dehesas, experience significant structural changes that affect their ability to support
habitats for a rich biodiversity. The goal of this study is to provide quantitative information on loss, fragmentation, and
alteration of holm oak (Quercus ilex) stands over a 42-year period, based on two sites in the lowlands of Cáceres province, Spain. Aerial photography and orthoimages
from 1956, 1984, and 1998 were processed in a geographic information system (GIS). Important changes in demography and land-use
were rural depopulation, abandonment of traditional agricultural activities, and a sharp increase in livestock stocking levels.
These were related to intensification and extensification of land-uses determined by national and EU agricultural policies.
Results of the land cover analysis indicated that dehesas suffered an annual 0.27% and 0.04% decrease in cover in the two
sites. From 1984 loss rate had markedly accelerated (0.83% and 0.30%). Most dehesas were lost by shrub encroachment or conversion
to open grassland. Fragmentation through roads increased by 28% and 45%, while rural buildings decreased by 17% and 50% from
1956 to 1998. Mean tree density decreased from 1956 to 1984, but a recovery was found since 1984. Significant factors determining
stand densities in most time points were altitude (related with different land-uses and geological substrates), ownership,
and proximity to villages. This suggests that stand structure is controlled both by human interventions and ecological settings.
The findings support the view that opposite trends of land abandonment and intensification of land-uses arise in most northern
Mediterranean countries as an effect of the EU Common Agricultural Policy. 相似文献
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A 4-month-old Thoroughbred filly presented for abdominal pain was diagnosed with a T-shaped malformation of the ventral colon at exploratory laparotomy. Following resection and anastomosis of the large colon, no further episodes of abdominal pain occurred during a 12-month follow-up. Acute dehiscence of the linea alba occurred as a complication of the initial laparotomy, but was successfully managed following additional surgical repair. T-shaped malformation of the ventral colon has not previously been reported and is considered a congenital malformation of mesocolon formation. 相似文献