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71.
Identifying corn plant location and/or spacing is important for predicting yield potential and making decisions for in-season nitrogen application rate. In this study, an automatic corn stalk identification system based on a laser line-scan technique was developed to measure stalk locations during corn mid-growth stages. A laser line-scan technique is advantageous in this application because the line-scan data sets taken from various points of view of a plant stalk results in less interference and higher probability of plant recognition. Data were collected for two 10-meter-long corn rows at the growth stages of V8 and V10 using a mobile test platform in 2011. Each potential stalk cluster was identified in a scan and registered with the same stalks in previous scans. The final location of a stalk was the average of the measured locations in all scans. The current system setup with data processing algorithms achieved 24.0 and 10.0 % of mean total errors in plant counting at the V8 and V10 growth stages, respectively. The root-mean-squared error (RMSE) between system measured plant locations and manually measured ones were 2.3 and 2.6 cm at the V8 and V10 growth stages, respectively. The interplant spacing measured by the developed system had a good correlation with the manual measurement with an R 2 of 0.962 and 0.951 for the V8 and V10 growth stages, respectively. This system can be ultimately integrated in a variable-rate-spraying system to improve real-time, high spatial resolution variable-rate nitrogen applications.  相似文献   
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The objective of this study was to determine whether students in a veterinary curriculum at Mississippi State University would gain an understanding of medical terminology, as they matriculate through their courses, comparable to that obtained during a focused medical terminology unit of study. Evaluation of students' incidental learning related to medical terminology during the 2004/2005 and 2005/2006 academic years indicated that 88.7% and 81.9% of students, respectively, scored above 70% on a medical terminology exam by the end of the first year of the curriculum. For the 2004/2005 academic, 67.6% increased their percentage of correct answers above 70% from the first medical terminology exam to the third. For the 2005/2006 academic year, 61.1% of students increased their score above 70% from the first to the third exam. Our data indicate that students can achieve comprehension of medical terminology in the absence of a formal terminology course.  相似文献   
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Tramadol is a centrally acting analgesic with opioid and monoaminergic actions. Its clinical effects have been well characterized in humans, where it has been in use for many years, but little is known for veterinary species. This study evaluated the sedative, emetic, thiopental‐sparing and intraoperative respiratory and hemodynamic effects of tramadol in comparison to morphine for pre‐medication of dogs undergoing orthopedic surgery under halothane anesthesia. Sixteen adult, healthy, mixed breed dogs (8.0 ± 2.6 kg) were studied. Eight dogs were pre‐medicated with tramadol (1.0 mg kg‐1 IM) and the other eight with morphine (1.0 mg kg–1 IM). After 20 minutes, anesthesia was induced with thiopental and subsequently maintained with halothane in oxygen using a Bain system, with spontaneous respiration. Degree of sedation and occurrence of emesis were evaluated after pre‐anesthetic medication. Dose of thiopental necessary for tracheal intubation was compared between the two groups. Arterial blood gas analyzes were done before pre‐medication and at 60 minutes of anesthesia. Heart rate and noninvasive arterial blood pressure were recorded before pre‐medication and every 10 minutes during anesthesia. Observer was blinded of the treatment given for each dog. Tramadol produced no visible sedation and no vomiting, while morphine induced a moderate degree of sedation in all dogs and vomiting in 62% of them. Dogs pre‐medicated with tramadol required significantly more thiopental (17 ± 3.8 mg kg–1) for induction of anesthesia than those pre‐medicated with morphine (12 ± 1.8 mg kg–1). Pre‐medication with morphine was associated with significantly higher PaCO2 and lower pH at 60 minutes of anesthesia. The remaining respiratory parameters and the hemodynamic variables were similar between the two groups. In conclusion, dogs pre‐medicated with tramadol at 1 mg kg–1 IM do not become visibly sedated and require a greater amount of thiopental for induction of anesthesia than pre‐medication with morphine. As intraoperative respiratory function is better preserved with tramadol, it may be useful for pre‐medication of respiratory compromised patients.  相似文献   
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Many educators, especially those involved in professional curricula, are interested in problem solving and in how to support students' development into successful problem solvers. The following article serves as an overview of educational research on problem solving. Several concepts are defined and the transition from one theory to another is discussed. Educational theories describing problem solving in the context of behavioral, cognitive, and information-processing pedagogy are discussed. The final section of the article describes prior findings regarding expert-novice differences in problem solving of various kinds.  相似文献   
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Dietary capsaicin enhances disease resistance and immunity in various species. Because relatively little is known about the potential benefits of capsaicin when used on horses, this study was conducted to determine the effect of dietary capsaicin on measures of health in horses. Twelve horses were fed over 28 days a basal diet with three levels of dietary capsaicin: 0 mg (C), 50 mg (CAP50), or 100 mg (CAP100) per horse per day. Before feeding on day 0, horses were weighed, a blood sample taken, and a sample of synovial fluid from the left distal carpal joint was taken. Subsequent body weights and blood samples were obtained on days 7, 14, 21, and 28. On day 21, tetanus toxoid (TT) and an immunomodulator (EqStim) were given to each horse. On days 21 to 28, daily rectal temperature (RT) and blood samples were taken. On day 28, synovial fluid was obtained immediately after blood sampling and RT measurement. Synovial concentrations of prostaglandin E2 did not differ among dietary treatments or between days 0 and 28. No effect of dietary capsaicin on serum immunoglobulin G subclass T or α1-acid glycoprotein concentrations was observed. Serum haptoglobin was elevated (P < .0003) and RT increased (P < .05) after challenge with EqStim and TT; however, haptoglobin concentrations and RT did not differ due to diet. We conclude that the doses of dietary capsaicin fed to horses in this study had no beneficial effect on measures of joint health or the immune response in horses.  相似文献   
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A retrospective observational study was conducted to determine whether agricultural animal caseloads at veterinary teaching hospitals declined between 1995 and 1998. Thereafter, the effect of organizational and demographic factors on 1998 in-house agricultural animal caseloads was examined. Caseload data were obtained from the American Association of Veterinary Medical Colleges. Demographic and organizational data were obtained by surveys, telephone interviews, and web-based resources. Complete data were available from 25 veterinary colleges, and data from these schools were used in subsequent analyses. In 1998, in-house food animal caseload decreased relative to 1995 in 17 schools and increased relative to 1995 in 8 schools. This trend was not significant (P = .053); however, the power of the test was limited (.50). Mean 1998 caseload was 886 +/- 504. Among schools with a discipline-based organizational structure, annual mean caseload was 464 +/- 220. Among schools with a species-based organizational structure, mean caseload was 1,167 +/- 463. The regression model that best predicted caseload was a forward-stepping model that included only organizational structure as an independent variable. No additional independent variable was significantly associated with caseload.  相似文献   
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