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141.
OBJECTIVE: To determine outcome of open toggle rod stabilization in dogs with luxation of the hip joint. Design-Retrospective case series. ANIMALS: 62 dogs. PROCEDURES: Information on signalment, surgical procedure, and postoperative care was obtained from the medical records. A questionnaire was sent to all owners to solicit follow-up information. RESULTS: The distribution for time between luxation and surgery was bimodal, with 24 (39%) dogs examined < or = 2 days after injury and 23 (37%) examined > 7 days after injury. Postoperative complications developed in 16 of the 62 (26%) dogs, with complications developing within 1 week after surgery in 10 of the 16. The most common complication was reluxation, which occurred in 7 dogs. Dogs in which surgery time was < 2 hours were significantly less likely to have a reluxation (2/40 [5%]) than were dogs in which surgery time was > or = 2 hours (5/22 [23%]). When asked to rate current limb function (0 = no lameness and 5 = non-weightbearing lame) a minimum of 6 months after surgery, 23 of 27 (85%) owners indicated a score of 0 or 1. CONCLUSIONS AND CLINICAL RELEVANCE: Results of the present study suggest that toggle rod stabilization is an effective treatment for hip joint luxation in dogs. However, complications, particularly reluxation, were common.  相似文献   
142.
The Stardust spacecraft collected thousands of particles from comet 81P/Wild 2 and returned them to Earth for laboratory study. The preliminary examination of these samples shows that the nonvolatile portion of the comet is an unequilibrated assortment of materials that have both presolar and solar system origin. The comet contains an abundance of silicate grains that are much larger than predictions of interstellar grain models, and many of these are high-temperature minerals that appear to have formed in the inner regions of the solar nebula. Their presence in a comet proves that the formation of the solar system included mixing on the grandest scales.  相似文献   
143.
A 17 acre (6.9?ha) agroforestry research and extension alley cropping trial was established at the Center for Environmental Farming Systems in Goldsboro, North Carolina in January 2007, with a randomized block design with five replications. Loblolly pine (Pinus taeda), longleaf pine (Pinus palustris) and cherrybark oak (Quercus pagoda) were planted in staggered rows, with each species planted for 140?ft (43?m) per replication. Crop land alleys of 40?ft or 80?ft (12.2–24.4?m) wide were left between the tree rows. Crops of soybeans (Glycine max) and corn (Zea mays) were planted in alternating years since establishment. As of 2011, survival rates were 93% for cherrybark oak, 88% for longleaf pine and 97% for loblolly pine. Average tree diameter at ground level was 1.0?in (2.5?cm) for cherrybark oak, 2.1?in (5.3?cm) for longleaf and 3.2?in (8.1?cm) for loblolly. Heights averaged 4.6?ft (1.4?m) for cherrybark oak, 5.2?ft (1.6?m) for longleaf pine and 10.4?ft (3.2?m) for loblolly pine. Growth, yield and economic projections for traditional timber production indicated that species volumes and values tracked the height and diameter relationships measured on the site. Loblolly pine had the largest projected internal rate of return, at 7.2%, followed by longleaf pine with pine straw harvests at 5.5%, longleaf without pine straw at 3.5% and cherrybark oak at 1.9%. There might be more loss in crop and silvopasture production with loblolly, however, and production of pine straw for longleaf or game mast for cherrybark oak may offer other benefits. Crop yields on the sandy soils on the site were very poor during the 4?years observed, which had a series of droughts and floods. These led to net financial losses in those years for the demonstration site, but state-wide average farm budget returns did show moderate profits. The results support the merits of agroforestry systems in the upper South to diversify income and reduce financial risks.  相似文献   
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Tempering conditions of wheat grain change the quality of the flour, yet most experimental milling systems use a standard tempering without optimization. The effect of tempering condition on milling performance and flour functionality for soft red winter (SRW) wheat grain was tested by measuring flour yield, ash, polyphenol oxidase (PPO), and solvent retention capacity (SRC) in grain samples from three SRW cultivars (Roane, Cyrus, and Severn). Tempering was conducted with a full factorial design of initial wheat moisture, tempered wheat moisture, tempering temperature, and tempering time at two levels. Tempered wheat moisture had the largest effect on milling performance and flour functionality. Flour yield was more reduced for all samples tempered at 15% moisture than for samples tempered to 12% moisture. Flour quality of the 15% tempered sample was better than the 12% tempered samples due to less bran contamination as measured by flour ash and PPO. Increasing the tempering moisture increased flour sucrose SRC and lactic acid SRC but reduced sodium carbonate SRC for samples. Changing tempered wheat moisture changed flour yield and quality much more than did changing the length of time for tempering, the temperature at wheat is tempered, or differences in the initial moisture of the wheat before tempering. The last three effects could be used to improve flour yield in both the 12 and 15% tempered wheat treatment but the detrimental effects of these treatments on flour quality were minimal when combined with the 15% tempered wheat moisture treatment.  相似文献   
147.
气源及活性剂对曝气滴灌带水气单双向传输均匀性的影响   总被引:2,自引:2,他引:0  
曝气滴灌过程中水、氧、气传输均匀性是评价曝气灌溉质量的重要指标。活性剂的添加和传输方式的优选对曝气滴灌传输过程中微气泡的存在和溶解氧的保持有重要意义。为提高水气耦合物在滴灌过程中传输的距离和均匀性,该文采用Mazzei 1078文丘里空气射流器进行曝气增氧,以空气和氧气为供试气源,研究活性剂BS1000浓度(0、1、2和4 mg/L)和传输方式(单向和双向)对曝气滴灌下水、氧、气传输特性的影响。结果表明:曝气导致单向传输下流量均匀性略有下降,但可显著提高灌溉水中溶解氧和掺气比例;随着活性剂浓度的增加,掺气比例显著增加(P0.05);活性剂的添加促进了氧气曝气下溶解氧的增加;溶氧均匀性和流量均匀性随着活性剂浓度的增加无显著性变化,但单向传输下4 mg/L BS1000的出气均匀性较未添加活性剂显著降低;双向传输的流量均匀性、溶氧均匀性和出气均匀性分别在95%、96%和67%以上,较单向传输分别平均提高14.00%、4.05%和30.64%(P0.05),是曝气滴灌长程管道传输推荐的布置方式。研究结果为曝气滴灌过程中灌溉技术参数优化和管道的科学布置提供理论依据。  相似文献   
148.
Hoof balance radiographs are commonly used as the basis for corrective farriery decision‐making in horses, however there are limited published data quantifying effects of the stance of the horse or the horizontal radiographic beam angle. In this analytical study, the influence of variation of the horse's stance in the craniocaudal and lateromodial plane on hoof balance measurements as well as the influence of variation of the horizontal radiographic beam angle on dorsopalmar hoof balance measurements was examined. Distal left thoracic limb lateromedial radiographs were acquired using a standardized protocol while varying the craniocaudal stance of five horses, each selected to be sound and conformationally normal. Dorsopalmar foot radiographs were acquired while varying the lateromedial stance; and variable angle horizontal beam dorsopalmar foot radiographs were acquired while keeping the limb position constant. Analyses of measurements demonstrated that hoof pastern angle had a linear relationship (R2 = 0.89, P < 0.001) with craniocaudal stance of the horse. The relationship of joint angle and stance was greater for the distal interphalangeal joint angle (R2 = 0.89, P < 0.001) than the proximal interphalangeal joint angle (R2 = 0.65, P = 0.001). The distal phalanx angle did not change with craniocaudal stance variation. The proximal interphalangeal joint width, distal interphalangeal joint width, or distal phalanx height did not change with lateromedial stance variation, nor within a 15 degree dorsolateral to caudomedial and dorsomedial to caudolateral variation from the dorsopalmar axis. Findings indicated that positioning of the thoracic limb needs to be considered during radiographic interpretation and decision‐making for corrective farriery.  相似文献   
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Successful regeneration of northern red oak (Quercus rubra L.) on productive sites is problematic in eastern North American forests. Natural and artificial regeneration often cannot compete with fast-growing, shade intolerant species such as yellow-poplar (Liriodendron tulipifera L.). This study examines 5-year survival, growth, and competitive ability of planted northern red oak seedlings in various group selection harvest sizes in south-central Indiana, USA. Seedling stocktypes consisted of high (BHD; 75 seedlings m?2) and low (BLD; 21 seedlings m?2) nursery-bed-density bareroot seedlings, and small (CS; 11.4 L) and large (CL; 18.9 L) container seedlings. Group selection openings included large (0.400 ha), medium (0.100 ha), and small (0.024 ha) circular gaps in four stands. Larger stocktypes and gap sizes improved seedling height, diameter, and growth; ANOVA indicated only gap size was significant for seedling survival. Logistic regression showed survival was positively correlated to diameter at year 1, and aspect, gap size, and stocktype were significant predictors of survival. Our data indicated no differences in density of natural regeneration among gap sizes, although trends suggest greater numbers of bigger competitors in larger gaps sizes. Yellow-poplar regeneration was the tallest competitor of more than 50% of all northern red oak seedlings. Competitive status of seedlings after 5 years differed only by stocktype, with large container stock in a better competitive position than bareroot stock. However, less than 20% of seedlings in all stocktypes in each gap treatment were considered competitive (i.e., ≥80% of the height of tallest competitor) against their tallest competitor. The use of larger planting stock may offer greater opportunities for successfully regenerating northern red oak seedlings on productive sites but likely would have to be accompanied by treatments to reduce woody competition.  相似文献   
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