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231.
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A stochastic model was designed to calculate the cost-effectiveness of biosecurity strategies for bovine viral diarrhea virus (BVDV) in cow-calf herds. Possible sources of BVDV introduction considered were imported animals, including the calves of pregnant imports, and fenceline contact with infected herds, including stocker cattle raised in adjacent pastures. Spread of BVDV through the herd was modeled with a stochastic SIR model. Financial consequences of BVDV, including lost income, treatment costs, and the cost of biosecurity strategies, were calculated for 10 years, based on the risks of a herd with a user-defined import profile. Results indicate that importing pregnant animals and stockers increased the financial risk of BVDV. Strategic testing in combination with vaccination most decreased the risk of high-cost outbreaks in most herds. The choice of a biosecurity strategy was specific to the risks of a particular herd.  相似文献   
233.
Squamous cell carcinoma (SCC) accounts for approximately 10% of all feline tumors. The purpose of this retrospective study was to describe outcomes for a group of cats with oral SCC that were treated with palliative radiation therapy. Fifty‐four cats met the inclusion criteria of nonresectable, oral SCC treated with coarse fractionated megavoltage (MeV) radiation therapy. Radiation therapy for all cats was delivered with a 6 MeV linear accelerator. Total radiation doses of 24 Gray to 40 Gray were administered in three to four fractions, once‐per‐week over 4 to 5 weeks. Concurrent chemotherapy protocols varied and were administered at the discretion of the clinician and client. Forty‐nine patients completed the planned treatment protocols. Overall mean and median survival times for cats completing the planned treatment protocols were 127 and 92 days (n = 49). Mean and median survival times of cats receiving palliative radiation therapy alone were 157 and 113 days (n = 12). Mean and median survival times of patients receiving both radiation therapy and chemotherapy were 116 and 80 days (n = 37). Patients with sublingual tumors had a median survival time of 135 days (n = 15), compared to mandibular tumors that had a median survival time of 80 days (n = 26). For the majority of patients that completed the planned treatment protocol (65%), owners reported a subjectively improved quality of life. Findings from this uncontrolled study supported the use of palliative radiation therapy for cats with nonresectable oral squamous cell carcinoma.  相似文献   
234.
The provision of quality industrialized housing in Chongqing to meet demand is perceived by the Chongqing Construction Commission to be a key feature of the local construction industry's future development. The growing strategic importance of Chongqing as a developing municipality, at the junction of the Yangtze and Jialing rivers, will ensure continuing economic development in the region. To facilitate such development the local construction industry will need to react accordingly to provide new infrastructure, commercial development, and housing and recreation facilities. Clearly, this must be achieved in accordance with a robust Master Plan, which addresses all issues associated with the built environment and other environmental considerations relating to pollution, conservation and sustainability. Throughout the World it is becoming increasingly recognized that traditional forms of construction are not sustainable in the long term and that new concepts and methods of construction must be developed. Construction must more effectively utilize and re-cycle resources that would otherwise become depleted or exhausted. Further, all aspects of the in-use performance of buildings, especially housing, must be significantly improved. The situation in Chongqing is no exception to this perception and hence the purpose of this paper is to evaluate locally available resources and relevant resources elsewhere in China to assess the potential for adaptation for effective use in industrialized housing. A broad approach will be taken covering all forms of human and non-human resources, especially those resources which can be re-cycled rather than being consigned to waste. By-products from other industries will be considered, such as those from agriculture and manufacturing. A key aspect of this paper is the articulation of a framework to facilitate the realization and development of an industrialized housing system by the creation of an integrated supply chain capable of delivering the necessary design and performance features geared to affordability, conservation and sustainability. The paper will be concludes by presentation of recommendations regarding the introduction of a development strategy geared to an incremental timetable for implementation.  相似文献   
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An array of aligned carbon nanotubes (CNTs) was incorporated across a polymer film to form a well-ordered nanoporous membrane structure. This membrane structure was confirmed by electron microscopy, anisotropic electrical conductivity, gas flow, and ionic transport studies. The measured nitrogen permeance was consistent with the flux calculated by Knudsen diffusion through nanometer-scale tubes of the observed microstructure. Data on Ru(NH3)6(3+) transport across the membrane in aqueous solution also indicated transport through aligned CNT cores of the observed microstructure. The lengths of the nanotubes within the polymer film were reduced by selective electrochemical oxidation, allowing for tunable pore lengths. Oxidative trimming processes resulted in carboxylate end groups that were readily functionalized at the entrance to each CNT inner core. Membranes with CNT tips that were functionalized with biotin showed a reduction in Ru(NH3)6(3+) flux by a factor of 15 when bound with streptavidin, thereby demonstrating the ability to gate molecular transport through CNT cores for potential applications in chemical separations and sensing.  相似文献   
237.
Frozen par-fries were processed in January and February using BelRus and Russet Burbank potatoes which were obtained from the same source and held under the same storage conditions. Prior to par-frying the raw potato slices were treated chemically or physically in order to increase the amount of bound water, or to remove water. At each processing date total solids of the raw and treated tissue were determined. Par-fries were analyzed for fat content. Treated samples were microwave heated and evaluated for sensory qualities as compared to frozen par-fries heated in a conventional oven. In no cases were the microwaved fries superior to the oven-heated fries in color, flavor, or texture. Drying the blanched fries in an oven for 10 min. prior to par-frying produced a microwaved product that was quite similar to the oven-heated fries, particularly in the case of the BelRus potatoes. In all cases BelRus potatoes absorbed less fat on par-frying than did Russet Burbank potatoes.  相似文献   
238.
蓝耳病(PRRS)不像伪狂犬病,没有终身带毒的猪存在,只有持续感染的猪,感染过一种亚型的蓝耳病病毒(PRRSV)后,便不会再感染同一亚型的病毒,但却可以感染其他亚型的PRRSV。在美国,猪场净化蓝耳病的成功率是相当高的,其清除并不难,但是净化的关键在于以后如何继续保持阴性,防止重新再感染。  相似文献   
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