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991.
Kate A. Margalit DVM Kei Hayashi DVM PhD Diplomate ACVS Josh Jackson DVM Diplomate ACVS Sun Young Kim DVM MS Tanya C. Garcia MS K. Tomo Wiggans BS MEng Sean Aiken DVM Diplomate ACVS Susan M. Stover DVM PhD Diplomate ACVS 《Veterinary surgery : VS》2010,39(7):818-823
Objective: To report biomechanical properties of the Biologic Fixation System (BFX) acetabular cup impacted into a normal canine pelvis and to compare the effect of implant positioned to and beyond the medial acetabular wall. Study Design: In vitro cadaveric study. Animals: Hemipelves of mature, large‐breed dogs (n=6). Methods: For each dog, 1 hemipelvis was reamed to the depth of the acetabular wall (group A) and 1 was reamed an additional 6 mm after penetration of the medial cortex of the acetabulum (group B). The hemipelves were implanted with acetabular cups and loaded in compression through a matching femoral prosthetic component until failure. Specimen stiffness, and failure displacement, load, and energy were determined from load and displacement data and results between groups compared with a paired t‐test. Results: Mean failure load was greater in group A (3812 ± 391 N) than group B (2924 ± 316 N; P<.014). No other differences (P>.05) were observed between groups. Bone fracture (n=5) and cup displacement (1) occurred in group A whereas in group B there were 3 fractures and 3 cup displacements. Conclusions: Although medial placement of the BFX cup affected compressive failure loads, failure loads for both groups exceeded normal physiologic loads. Clinical Relevance: Medial positioning of the acetabular cup does not appear to compromise acetabular implant‐pelvic stability under normal physiologic loads. Because arthroplasty candidates often have abnormal acetabular architecture, mechanical properties of the cup placed in acetabula without a dorsal rim should be investigated. 相似文献
992.
993.
I. G. Shirokikh S. Yu. Ogorodnikova I. V. Dal’ke O. N. Shupletsova 《Russian Agricultural Sciences》2011,37(2):98-102
To produce new aluminum- and drought-resistant barley forms, selection has been carried out in callus cultures in selective
systems successively simulating the effect of the stressor. Plants regenerated in selective systems differed from control
plants by a higher content of chlorophyll and carotenoids, photosynthetic rate, water use efficiency, and productivity. 相似文献
994.
E. A. Kalashnikova Mai Dyk Chung A. A. Solov’ev V. S. Shevelukha 《Russian Agricultural Sciences》2011,37(1):4-7
The conditions of cultivating isolated anthers and microspores are optimized for the purpose of producing haploid rapeseed, white head cabbage, and cauliflower plants under in vitro conditions and the process of direct embryogenesis is studied. It is established that the presence of 1 mg/l kinetin and 1 mg/l naphthaleneacetic acid hormones in nutrient medium B5 stimulated the process of direct embryogenesis in rapeseed as well as the formation of secondary and tertiary embryoids on hypocotyl and leaf segments of sterile sprouts. A cytological analysis of regenerant plants (count of the number of chloroplasts in stomatal guard cells and chromosomes in root meristem) confirmed the haploid nature of the rapeseed plants. Regenerants are obtained from callus tissue of cabbage microspores. 相似文献
995.
S. L. Tyuterev K. V. Novozhilov E. F. Panarin E. V. Popova I. S. Kochetkova V. V. Azanova N. I. Vorob’ev 《Russian Agricultural Sciences》2011,37(1):25-30
An antibacterial composition with multifunctional biological activity for protecting plants against pathogens of bacterial infections has been created on the basis of the polymeric membrane-active nanodisperse antimicrobial preparation Katapol and a fungicide for preplanting treatment of vegetable seeds and potato tubers. The high protective effect of the composition is shown. 相似文献
996.
Kei Ishida Macarius Yangyuoru Koichi Unami Toshihiko Kawachi 《Paddy and Water Environment》2011,9(4):393-401
Analysis of runoff processes in farmlands during storm events in particular is an important engineering topic. The shallow
water equations describing the physical conservation laws are attractive tools for understanding motion of surface water.
A numerical model is developed to reproduce surface water flows during storm events, using the finite element method and the
finite volume method applied to the one-dimensional shallow water equations. The numerical model has the advantage of dealing
with transcritical flows, wet, and dry processes, irregular channel bed slopes, and channel junctions involving multiply connected
networks. Standard numerical tests demonstrated some of these features. Runoff processes from farmlands in a Japanese hilly
area is analyzed with the numerical model coupled with another runoff model of black-box type. Parameters of the models are
calibrated and validated using observed series of rainfall and runoff discharge data. Simulated results included submergence
of hydraulic jumps and flood storage in farming plots, which are very informative in terms of assessing diverse functions
of the farmlands. 相似文献
997.
Multi-functional landscapes in semi arid environments: implications for biodiversity and ecosystem services 总被引:4,自引:2,他引:2
P. J. O’Farrell B. Reyers D. C. Le Maitre S. J. Milton B. Egoh A. Maherry C. Colvin D. Atkinson W. De Lange J. N. Blignaut R. M. Cowling 《Landscape Ecology》2010,25(8):1231-1246
Synergies between biodiversity conservation objectives and ecosystem service management were investigated in the Succulent Karoo biome (83,000 km2) of South Africa, a recognised biodiversity hotspot. Our study complemented a previous biodiversity assessment with an ecosystem service assessment. Stakeholder engagement and expert consultation focussed our investigations on surface water, ground water, grazing and tourism as the key services in this region. The key ecosystem services and service hotspots were modelled and mapped. The congruence between these services, and between biodiversity priorities and ecosystem service priorities, were assessed and considered in relation to known threats. Generally low levels of overlap were found between these ecosystem services, with the exception of surface and ground water which had an 80% overlap. The overlap between ecosystem service hotspots and individual biodiversity priority areas was generally low. Four of the seven priority areas assessed have more than 20% of their areas classified as important for services. In specific cases, particular service levels could be used to justify the management of a specific biodiversity priority area for conservation. Adopting a biome scale hotspot approach to assessing service supply highlighted key management areas. However, it underplayed local level dependence on particular services, not effectively capturing the welfare implications associated with diminishing and limited service provision. We conclude that regional scale (biome level) approaches need to be combined with local level investigations (municipal level). Given the regional heterogeneity and varied nature of the impacts of drivers and threats, diverse approaches are required to steer land management towards sustainable multifunctional landscape strategies. 相似文献
998.
采用Y型嗅觉仪,测定椰甲截脉姬小蜂(Asecodes hispinarum)雌成虫对离体0~72 h未受害椰子心叶、不同头数为害的椰心叶甲(Brontispa longissima)幼虫-椰子心叶复合体、不同时间椰心叶甲幼虫-椰子心叶复合体、机械损伤心叶、成虫为害心叶、3龄幼虫-心叶复合体、3龄幼虫为害去虫叶、幼虫+粪便及挥发物标样的行为反应,并对椰子挥发性化学物质作了GC-MS测定。结果表明:(1)离体0~72 h未受害椰子心叶挥发物对椰甲截脉姬小蜂没有显著的引诱作用。(2)10、15、20头/叶3龄椰心叶甲幼虫为害24 h后,幼虫-椰子心叶复合体挥发物对椰甲截脉姬小蜂有显著的吸引作用,其它为害头数的复合体对椰甲截脉姬小蜂没有显著的吸引作用。(3)10头3龄椰心叶甲幼虫为害20~48 h,幼虫-椰子心叶复合体挥发物对椰甲截脉姬小蜂有显著的吸引作用,其它受害时间吸引作用不显著。(4)受害椰子心叶去除幼虫和粪便前后,挥发物对该蜂的引诱作用没有显著差异;未受害心叶、机械损伤心叶、3龄幼虫和粪便对椰甲截脉姬小蜂没有显著的吸引作用。(5)GC-MS分析结果表明,3龄幼虫为害前后,椰子心叶挥发物的含量和成分发生了变化,受害后增加了4种成分:(E)-4,8-二甲基-1,3,7-壬三烯、未知物2、未知物3和苯甲酸乙酯4种物质。(6)椰子挥发物标准品(E)-4,8-二甲基-1,3,7-壬三烯在5×10-2μL/μL和5×10-3μL/μL浓度下,对椰甲截脉姬小蜂有显著的引诱作用,其它浓度对椰甲截脉姬小蜂没有显著的吸引作用。由此可见,椰子心叶受椰心叶甲为害后,诱导的挥发物质为椰甲截脉姬小蜂寻找寄主提供化学信息。 相似文献
999.
Jun Iguchi Yasuharu Takashima Atsushi Namikoshi Yumiko Yamashita Michiaki Yamashita 《Fisheries Science》2013,79(6):977-982
The correlations among the contents of trace elements in the shells of short-neck clams collected from Japan, China, and the Republic of Korea were examined. Origin-specific elemental content patterns were seen in clams originating from Japan, China, and the Republic of Korea. The crushed shells were decomposed with nitric acid–hydrogen peroxide, and the concentrations of ten elements (Li, V, Mn, Co, As, Rb, Mo, Ba, Pb, and U) in the shells were measured by inductively coupled plasma mass spectrometry. Some of the metal concentrations in the samples displayed clear geographical trends. The average concentration of Pb in Japanese clam shells was one-half to one-quarter that seen in Chinese or Korean clams. Average concentrations of As, Rb, and Ba in shells of Japanese origin were one-half those observed in Chinese or Korean clams. Linear discriminant analysis was applied to these analytical data, and four discriminant models were constructed. These discriminant models were able to distinguish the geographic origins of short-neck clams with 80.0–100 % accuracy. In particular, clams of Japanese origin were classified correctly ≥90 % of the time. Therefore, the trace elemental analysis of a short-neck clam shell is useful for identifying the country of origin of the clam. 相似文献
1000.
Amy B. Alford Richard M. Kaminski Stephen C. Grado Louis R. D’Abramo Jimmy L. Avery 《Aquaculture Economics & Management (Blackwell Science)》2013,17(2):295-313
ABSTRACTCrayfish harvest as an ecosystem service of moist-soil wetlands in the Mississippi Alluvial Valley (MAV) was evaluated using estimates of crayfish yield and operational costs to create enterprise budgets. The average daily yield of crayfish was 2.13 lb/acre (95% CI = 1.19–3.00) and yield did not differ between wetlands dominated with Red Swamp Crayfish or White River Crayfish. Four hypothetical scenarios of harvest operations revealed annual costs associated with harvesting crayfish to be $163.89–370.75/acre. Although these costs were lower than estimated costs currently associated with harvesting crayfish from fields with planted forage in Louisiana ($749.96/acre), a three-fold reduction in crayfish yield (lb/trap/day) from moist-soil wetlands resulted in an increase in the break-even selling price from $1.25/lb in Louisiana to $1.70–$3.86/lb in the MAV. Although this enterprise will likely not compete with the Louisiana rice-crayfish industry, harvesting crayfish from moist-soil wetlands may contribute to ecosystem services provided by wetlands and aid in the reduction of the quantity of crayfish products imported into the U.S. market. 相似文献