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61.
62.
Bird strikes to aircraft are a globally pervasive safety and economic concern. In particular, the Anchorage, Alaska area holds substantial risk for destructive collisions between birds and aircraft. An international airport, a municipal airport, a seaplane base, and a U.S. Air Force base are situated throughout the area. Anchorage also has a burgeoning population of Canada geese (Branta canadensis parvipes), one of the species identified as posing the greatest airstrike hazards. A variety of methods are applied and a variety of research has been conducted to reduce the potential for airstrikes with geese around Anchorage. We review the nature of the problem, as well as the research and mitigation procedures applied to address the problem.  相似文献   
63.

Objective

To determine signalment, injury type, trauma severity score, and outcome of feline trauma patients undergoing surgical (emergency room [ER] and operating room [OR]) and nonsurgical treatments in addition to time to surgery, specialty services involved, and cost in the OR surgery population.

Design

Retrospective evaluation of medical record and hospital trauma registry data on feline trauma cases.

Setting

University teaching hospital.

Animals

Two hundred and fifty-one cats presenting for traumatic injury between May 2017 and July 2020.

Interventions

None.

Measurements and Main Results

Demographics and outcomes were compared for cats undergoing surgical intervention in an OR (12%, 31/251) or an ER (23%, 58/251) setting and feline trauma patients without surgical intervention (65%, 162/251). Between the 2 surgical groups, 99% survived to discharge compared to 73.5% of the nonsurgical group (P < 0.0001). For the OR surgical cohort, electronic medical records were reviewed to determine the specialty surgery service involved, time to and duration of anesthesia and surgery, and visit cost. The most common surgery services involved were orthopedics (41%, 12/29) and dentistry (38%, 11/29), and the most common surgeries performed were mandibular fracture stabilization (8/29) and internal fixation for long bone fractures (8/29). The ER surgical group had a significantly lower Animal Trauma Triage score than the OR group (P < 0.0001), but a significant difference was not found between OR surgical and nonsurgical groups (P = 0.0553). No difference in modified Glasgow Coma Scale score was found between any groups.

Conclusions

Surgical intervention in feline trauma patients appears to be associated with higher survival rates, but no difference in mortality was found across surgery services. OR surgical intervention, in particular, orthopedic surgery, was associated with increased length of hospitalization, increased cost, and increased use of blood products.  相似文献   
64.
Radiography, magnetic resonance imaging (MRI), and ultrasonography are commonly used for diagnosis of shoulder osteochondrosis and osteochondritis dissecans (OC/OCD) in dogs, however there is a lack of published information on the relative diagnostic sensitivities of these modalities. The purpose of this prospective study was to compare diagnostic sensitivities of these modalities for detecting shoulder OC/OCD in a group of dogs, using arthroscopy as the reference standard. Inclusion criteria were history and clinical findings consistent with osteochondrosis and/or osteochondritis dissecans involving at least one shoulder. With informed client consent, both shoulders for all included dogs were examined using standardized radiography, ultrasonography, MRI, and arthroscopy protocols. One of three veterinary surgeons recorded clinical and arthroscopic findings without knowledge of diagnostic imaging findings. One of two veterinary radiologists recorded diagnostic imaging findings without knowledge of clinical and arthroscopic findings. Eighteen client‐owned dogs (n = 36 shoulders) met inclusion criteria. Diagnostic sensitivity, specificity, and accuracy (correct classification rate) values for detecting presence or absence of shoulder osteochondrosis/osteochondritis dissecans were as follows: radiography (88.5%, 90%, 88.9%), ultrasonography (92%, 60%, 82.6%), and MRI (96%, 88.9%, 94.4%). Odds of a correct diagnosis for MRI were 3.2 times more than ultrasonography and two times more than radiography. For MRI detection of lesions, the sagittal T2 or PD‐FAT SAT sequences were considered to be most helpful. For radiographic detection of lesions, the additional supinated‐mediolateral and pronated‐mediolateral projections were considered to be most helpful. Findings from the current study support more evidence‐based diagnostic imaging recommendations for dogs with clinically suspected shoulder osteochondrosis or osteochondritis dissecans.  相似文献   
65.
The current standard of care treatment for canine lymphoma is a multi-agent, CHOP-based chemotherapy protocol. Single agent doxorubicin (DOX) is less burdensome; however, multi-agent chemotherapy protocols are often superior. The recently approved drug rabacfosadine (RAB, Tanovea) provides an attractive option for combination therapy with DOX, as both drugs demonstrate efficacy against lymphoma and possess different mechanisms of action. A previous study evaluating alternating RAB/DOX reported an overall response rate (ORR) of 84%, with a median progression-free survival time (PFS) of 194 days. The aim of this prospective trial was to evaluate the same protocol in an additional population of dogs. Fifty-nine dogs with treatment naïve lymphoma were enrolled. RAB (1.0 mg/kg IV) was alternated with DOX (30 mg/m2 IV) every 21 days for up to six total treatments (3 cycles). Response assessment and adverse event (AE) evaluation were performed every 21 days using VCOG criteria. The ORR was 93% (79% CR, 14% PR). The median time to maximal response was 21.5 days; median PFS was 199 days. T cell immunophenotype and lack of treatment response were predictive of inferior outcomes. AEs were mostly gastrointestinal. Six dogs developed presumed or confirmed pulmonary fibrosis; four were grade 5. One dog experienced grade 3 extravasation injury with RAB that resolved with supportive treatment. These data mirror those of the previously reported RAB/DOX study, and support the finding that alternating RAB/DOX is a reasonable treatment option for canine lymphoma.  相似文献   
66.
Wheat (Triticum aestivum L.) fields in the semi-arid Northern Great Plains are spatially variable in soil N fertility and crop productivity. Consequently, there is interest in applying variable, rather than uniform rates of fertilizer N across the landscape. Intensive soil sampling as a basis for variable-rate fertilizer management is too costly when compared to the value of wheat in this region. The objective of this research was to determine relationships between yield and protein, and protein and available N as needed to develop a cost-effective variable-rate N fertilizer strategy for spring wheat. A three-year study (1996–1998) was carried out at a site near Havre, Montana, USA (48°30N, 109°22W). Treatments consisted of three water regimes, four cultivars, and five fertilizer N levels per water regime in a randomized complete block design with four replicates. Scatter diagrams of relative yield vs. grain protein were consistent with earlier investigators, and indicated protein concentrations at harvest provided a method for indexing N nutrition adequacy (deficiency vs. sufficiency) in wheat. A critical protein concentration of 13.2% was defined using a graphical Cate-Nelson analysis. This value appeared to be consistent across the three water regimes and four cultivars as 159 (88%) of the 180 water×cultivar×N level episodes were in positive quadrants. No correlation could be found between relative yield and protein for episodes below the critical level (r2=0.1). Hence, grain protein concentrations could not be used to predict the magnitude of yield losses from N deficiency. Grain protein content would be useful for prescribing fertilizer recommendations where N deficiency (<13.2% protein) reduces grain yield under semi-arid conditions. Inverse slopes (dy/dx) of the protein-available N curves reveal that it takes 12–18 kg N/ha to change protein 1% (e.g., 12% vs. 13%) where wheat is under water stress during grain fill. The total N requirement could then be computed by summing the N required for raising protein and the N removed by the crop in the year when the grain was harvested.  相似文献   
67.
In mammals, hair cell loss causes irreversible hearing and balance impairment because hair cells are terminally differentiated and do not regenerate spontaneously. By profiling gene expression in developing mouse vestibular organs, we identified the retinoblastoma protein (pRb) as a candidate regulator of cell cycle exit in hair cells. Differentiated and functional mouse hair cells with a targeted deletion of Rb1 undergo mitosis, divide, and cycle, yet continue to become highly differentiated and functional. Moreover, acute loss of Rb1 in postnatal hair cells caused cell cycle reentry. Manipulation of the pRb pathway may ultimately lead to mammalian hair cell regeneration.  相似文献   
68.
Susceptibility artifacts caused by ferromagnetic implants compromise magnetic resonance imaging (MRI) of the canine stifle after tibial plateau leveling osteotomy (TPLO) procedures. The WARP‐turbo spin echo sequence is being developed to mitigate artifacts and utilizes slice encoding for metal artifact reduction. The aim of the current study was to evaluate the WARP‐turbo spin echo sequence for imaging post TPLO canine stifle joints. Proton density weighted images of 19 canine cadaver limbs were made post TPLO using a 3 Tesla MRI scanner. Susceptibility artifact sizes were recorded and compared for WARP vs. conventional turbo spin echo sequences. Three evaluators graded depiction quality for the tibial tuberosity, medial and lateral menisci, tibial osteotomy, and caudal cruciate ligament as sufficient or insufficient to make a diagnosis. Artifacts were subjectively smaller and local structures were better depicted in WARP‐turbo spin echo images. Signal void area was also reduced by 75% (sagittal) and 49% (dorsal) in WARP vs. conventional turbo spin echo images. Evaluators were significantly more likely to grade local anatomy depiction as adequate for making a diagnosis in WARP‐turbo spin echo images in the sagittal but not dorsal plane. The proportion of image sets with anatomic structure depiction graded adequate to make a diagnosis ranged from 28 to 68% in sagittal WARP‐turbo spin echo images compared to 0–19% in turbo spin echo images. Findings indicated that the WARP‐turbo spin echo sequence reduces the severity of susceptibility artifacts in canine stifle joints post TPLO. However, variable depiction of local anatomy warrants further refinement of the technique.  相似文献   
69.
A growth model is developed for coho salmon which accounts for temperatures and feeding rates typically encountered in fish hatchery operation. Feeding rates utilized by the model ranged from maintenance to maximum utilizable rations. The model is derived from an empirical equation for maximum growth rate, and a theoretical equation for net energy utilization. The resultant equation is modified to improve fit at higher feeding levels. Calibration is accomplished with experimentally obtained data.

The model is similar to one developed by G.D. Stauffer, but represents an improvement because points on the growth curve between maintenance and maximum ration can be fitted even if maintenance and maximum requirements are obtained independently.  相似文献   

70.
Cottonwoods occur in riparian areas where water table depth generally varies with the elevation of the adjacent river. Plant adaptation to the riparian zone requires the coordination of root elongation to maintain contact with the water table during the summer decline. We investigated the effects of rate of water decline on growth allocation and concentrations of endogenous gibberellins (GAs) in black cottonwood (Populus trichocarpa Torr. & A. Gray ex Hook.) saplings. Rhizopods were used to achieve water decline rates of 0, 2 and 4 cm day(-1). Root elongation approximately doubled in response to the 2 cm day(-1) treatment, whereas leaf area was reduced. A water decline rate of 4 cm day(-1) led to water stress, as evidenced by reduced growth, increased leaf diffusive resistance, decreased water potential, and leaf senescence and abscission. Endogenous GAs were extracted, purified and analyzed by gas chromatography-selected ion monitoring with internal [(2)H(2)]GA standards. Across the sampled plant organs, GAs were generally highest in shoot tips and sequentially lower in basal stems, root tips, leaves and upper roots; GAs were thus abundant in rapidly growing tissues. Of the GAs measured, GA(1) tended to predominate, followed sequentially by GA(3), GA(8), GA(19), GA(20), GA(29) and GA(4). There was little relationship between GA concentration and growth allocation across the water table decline treatments, although GA(8) was consistently reduced in plants experiencing water table decline. Because GA(8) is the final gibberellin in the metabolic sequence, it might be useful for assessing historic patterns of GAs and growth rate. This study demonstrated changes in growth allocation in response to water table decline, but provided little evidence that endogenous GAs play a primary role in the regulation of root elongation in response to water table decline.  相似文献   
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