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331.
This study was conducted to investigate the efficacy of rocuronium bromide as mydriatic agent in domestic pigeons (Columba livia). This study was done in two phases. In the first phase, rocuronium bromide (0.20 mg/20 µl) was topically instilled to the right eye (OD) of eight domestic pigeons. Pupil diameter was measured before instillation (T0), and at 5 (T05) and 10 (T10) min after instillation, and every 10 min thereafter until 160 (T160) min. Pupillary light reflex (PLR) was assessed using a scoring system at the same time points. In the second phase, the same dosage was instilled twice in the span of 10 min into both eyes (OU) of four pigeons (eight eyes). Measurements were done accordingly. The iris color in the first phase were: gravel, pearl and bull eye. All irises in the second phase were bull eye. Mydriasis were observed in 6/8 (75%) pigeons in the first phase. Maximal mydriasis was observed at T30 (mean pupil diameter=4.62 ± 0.13 mm). Pupil diameter in the treated eye was significantly different from contralateral eye and from T0 since T05 (P=0.017 and P=0.006, respectively)−T120 (P=0.043 and P=0.044, respectively). PLR was disappeared from T10 (P=0.034) to T90 (P=0.041). In the second phase, mydriasis was only observed in 2/8 eyes. This study suggested that rocuronium bromide was able to produce mydriasis in pigeons other than bull eye iris.  相似文献   
332.
333.
Sericite is mica-based natural clay that is annealed at 800 ℃ for 4 h, followed by acid activation using 3.0 mol L-1HCl at 100℃. The interaction of cesium(I), Cs(I), with sericite could provide useful data for the study of soil erosion or mass water movement utilizing the natural radioactive Cs. In this study sericite and activated sericite were used to assess their suitability in the attenuation of Cs from the aquatic environment under both batch and column experiments. The surface morphological studies indicated that a disordered and heterogeneous surface structure was exhibited by the activated sericite, whereas the native sericite exhibited a compact and layered structure. The Brunauer-Emmett-Teller(BET) specific surface area results indicated a significant increase in the surface area due to the activation of sericite. The batch reactor data collected for various parametric studies revealed that an increase in p H(from 2.0 to 8.0) and sorbate concentration(from 10.0 to 100.0 mg L-1) apparently favored the attenuation of Cs(I). The timedependent sorption data revealed that Cs(I) uptake was very rapid, and it achieved its saturation value within just 50 min of contact.The kinetic modeling studies indicated that the uptake of Cs(I) followed a pseudo-second-order rate equation; hence, the attenuation capacity of these solids for Cs(I) was estimated to be 0.858 and 4.353 mg g-1for sericite and activated sericite solids, respectively.The adsorption isotherm modeling data showed a reasonably good applicability of the Freundlich model than the Langmuir model.The effect of background electrolyte concentrations(0.001 to 0.1 mol L-1) of Mg(NO3)2indicated that the presence of this electrolyte could not significantly affect the percent removal of Cs(I) by activated sericite. Furthermore, the fixed-bed column reactor operations were performed to obtain the breakthrough data, which were fitted well to the Thomas non-linear equation. Therefore, the loading capacity of Cs(I) was estimated to be 1.585 mg g-1at the initial influent Cs(I) concentration of 30.0 mg L-1at p H 5.0.  相似文献   
334.
In this study, real-time disease monitoring was conducted on onion which is the most representative crop in Republic of Korea, using an image acquisition system newly developed for the mobile measurement of phenotype. The purpose of this study was to improve the accuracy of prediction of disease and state variables by processing images acquired from monitoring. The image acquisition system was consisted of two parts, a motorized driving system and a PTZ (pan, tilt and zoom) camera to take images of the plants. The acquired images were processed as follows. Noise was removed through an image filter and RGB (red, green and blue) colors were converted to HSV (hue, saturation and value), which enabled thresholding of areas with different colors and properties for image binarization by comparing the color of onion leaf with ambient areas. Four objects with the most significant browning in the onion leaf to the naked eye were selected as the samples for data acquired. The thresholding method with image processing was found to be superior to the naked eye in identifying accurate disease areas. In addition, it was found that the incidence of disease was different in each disease area ratio. As a result, the use of image acquisition system in image processing analysis will enable more prompt detection of any changes in the onion and monitoring of disease outbreaks during the crop lifecycle.  相似文献   
335.
At an early immature growth stage of citrus, a hyperspectral camera of 369–1042 nm was employed to acquire 30 hyperspectral images in order to detect immature green fruit within citrus trees under natural illumination conditions. First, successive projections algorithm (SPA) were implemented to select 677, 804, 563, 962, and 405 nm wavebands and to construct multispectral images from the original hyperspectral images for further processing. Then, histogram threshold segmentation using NDVI of 804 and 677 nm was implemented to remove image backgrounds. Three slope parameters, calculated from the pairs 405 and 563 nm, 563 and 677 nm, and 804 and 962 nm were used to construct a classifier to identify the potential citrus fruit. Then, a marker-controlled watershed segmentation based on wavelet transform was applied to obtain potential fruit areas. Finally, a green fruit detection model was constructed according to Grey Level Co-occurrence Matrix (GLCM) texture features of the independent areas. Three supervised classifiers, logistic regression, random forest and support vector machine (SVM) were developed using texture features. The detection accuracies were 79%, 75%, and 86% for the logistic regression, random forest, and SVM models, respectively. The developed algorithm showed a great potential for identifying immature green citrus for an early yield estimation.  相似文献   
336.
This study aimed to investigate the effect of mydriasis using topical rocuronium bromide on electroretinography (ERG) in domestic pigeons (Columba livia). Scotopic mixed rod and cone, photopic cone, and photopic flicker ERG were performed on nine eyes of nine healthy adult pigeons under sedation. Each pigeon underwent two sets of ERG recordings. First, without the induction of mydriasis (control) and the second time with the induction of mydriasis using topical rocuronium bromide (treatment). The results were compared using either the Student’s t-test or Wilcoxon rank-sum test, where a P-value of <0.05 was considered statistically significant. No significant differences were observed in the a- and b-wave implicit times and amplitudes during scotopic ERG between the two groups. The a- and b-wave amplitudes in the photopic cone were significantly higher in the treatment group (63.83 ± 32.33 and 191.75 ± 94.46 µV) compared to the control group (46.15 ± 27.60 and 116.76 ± 70.65 µV; P=0.045 and P=0.032, respectively). The photopic flicker amplitude was also significantly higher in the treatment group (76.23 ± 48.56 µV) than in the control group (42.18 ± 31.18 µV; P=0.044). No statistically significant differences were observed in the photopic cone and flicker implicit times between both groups. In conclusions, mydriasis induced by rocuronium bromide in pigeon resulting in higher amplitudes during the photopic ERG but not scotopic ERG.  相似文献   
337.
The alpha-macroglobulins are broad-specificity protease inhibitors important in the regulation and clearance from circulation of biologically active proteases. Inappropriate protease activation may be a feature of canine acute pancreatitis and the ability of the animal to clear these proteases may be important in determining survival. An enzyme immunoassay for the detection and measurement of canine alpha-macroglobulins in plasma samples was developed. A reference range for the canine alpha-macroglobulins of 1.20-2.72 mg ml-1 was established from a panel of canine plasma samples, and the stability of the alpha-macroglobulins in plasma samples stored at 4 degrees C was investigated. Changes in the level of the alpha-macroglobulins during disease states involving increased endogenous protease activity can now be investigated using a rapid, repeatable and quantifiable assay.  相似文献   
338.
Abstract An experimental fishway was used to examine adult Pacific lamprey, Lampetra tridentata (Gairdner), behaviour in a series of attraction and passage‐performance tests. Among all experiments, lamprey oriented to the fishway floor and walls and were attracted to both ambient and concentrated flow. When confronted with high‐velocity areas (vertical‐slot and submerged‐orifice weirs), many lamprey failed to pass upstream. However, lamprey were able to find and take advantage of low‐velocity refuges when they were provided. Lamprey climbed shallow‐ and steep‐angled ramps when attraction cues were sufficient and other passage routes were restricted. The combined results demonstrated the passage challenges that fishways designed and operated for salmonids present to non‐salmonid species. They also highlight the importance of evaluating trade‐offs between fishway attraction and passage efficiency. The experiments were integrated with tagging studies and development of lamprey‐specific passage structures, a research combination that provided an effective template for fishway performance evaluations.  相似文献   
339.
通过对光谱仪采集的340~1 030 nm柑橘健康与感染黑斑区域光谱进行分析,在探明健康和黑斑病不同症状光谱特性的基础上,提出主成分分析结合特征排序的方法,选择出可识别染病与健康样本的最优波长(525 nm)建立SMO分类模型;基于序列浮动前向选择方法优选出4个特征波长(678、740、794、879 nm),建立C4.5算法识别柑橘黑斑病3种症状的方法。试验结果表明,用525 nm波长建立的SMO分类模型对健康和染病果样本的识别率达99.37%,硬斑型、破裂型和黑斑型症状的识别率分别为81.85%、71.88%和67.57%,3种症状的平均识别率为73.77%,比前人方法提高了12.77个百分点。  相似文献   
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