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71.
Tung Hsueh Chung-Chun Yang Shiun-Long Lin I-Ping Chan 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(6):2677-2681
A 3-month-old intact female American Shorthair cat, with syncope and tachypnea, underwent cardiac examination which identified no heart murmur or gallop. Thoracic radiography disclosed mild generalized enlargement of the cardiac silhouette and a bronchial and interstitial pattern throughout the lungs. Echocardiography identified tubular structures near the left atrium. After agitated saline contrast imaging, persistent left cranial vena cava with unroofed coronary sinus was suspected. Computed tomography angiography showed the right cranial, right caudal and left caudal pulmonary veins draining into the coronary sinus and flowing into the right atrium. The left cranial pulmonary vein drained normally into the left atrium. Partial anomalous pulmonary venous connection (PAPVC) was diagnosed. The kitten was treated with diuretics but died of heart failure 2 months later. Permission for necropsy was not granted. This case represents symptomatic PAPVC in a kitten. Most pulmonary veins were connected abnormally with the coronary sinus. The prognosis was grave because of refractory heart failure. 相似文献
72.
The arrangement of land use substantially affects outdoor human comfort. The purposes of this study were to develop a spatial optimization procedure that involves combining simulated annealing algorithm with a microclimate model (ENVI-met) and to identify the relationship between the spatial pattern of the major cooling source and human comfort. The procedure is an assessment tool for appropriately designing living space on a community scale. The physiological equivalent temperature (PET) was used as the index of human comfort, and the objective of optimization was to minimize the difference in the PET to 23 °C within the study area. Four types of land use, namely buildings, paddies, parks, and ponds, were considered. Given the types of land use and the land areas, the procedure is used to determine the optimal layout that provides the most comfortable environment. The results revealed that the optimal design effectively improved the homogeneity of human comfort quantitatively and spatially in summer. Human comfort in the entire area was improved when the prevailing wind first passes through cooling sources, such as the paddies, and the walkways are easier to cool when the cooling sources are located nearby. The results of the spatial optimization procedure can further be applied to determine the relationship between the spatial pattern of land use and human comfort, and the relationship can be used as a reference for future research on community design. 相似文献
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74.
Zhang Q Lambert G Liao D Kim H Robin K Tung CK Pourmand N Austin RH 《Science (New York, N.Y.)》2011,333(6050):1764-1767
The emergence of bacterial antibiotic resistance is a growing problem, yet the variables that influence the rate of emergence of resistance are not well understood. In a microfluidic device designed to mimic naturally occurring bacterial niches, resistance of Escherichia coli to the antibiotic ciprofloxacin developed within 10 hours. Resistance emerged with as few as 100 bacteria in the initial inoculation. Whole-genome sequencing of the resistant organisms revealed that four functional single-nucleotide polymorphisms attained fixation. Knowledge about the rapid emergence of antibiotic resistance in the heterogeneous conditions within the mammalian body may be helpful in understanding the emergence of drug resistance during cancer chemotherapy. 相似文献
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77.
Residual bran on milled rice is directly related to its quality. This study proposes a method to measure the residual bran patterns on a single rice grain by using hyperspectral imaging (HSI). HSI is a sensing technique that combines both spatial and spectral information and may be used for chemical compound identification and quantification. In this study, HSI was applied to assess rice bran residue nondestructively. In the experiment, rice samples were milled and scanned with an HSI system. Afterward, the rice samples were dyed to enable the residual bran to be identified with optical microscopy and image processing algorithms. Classifiers were then developed to predict the rice bran residue by using the HSI measurements as inputs. The predicted images were compared with the micrograph images for classifier performance evaluation. The proposed approach can estimate the residual bran distribution on milled rice surface with an accuracy of 93.5%. 相似文献
78.
Maturation and spawning performance of pond-reared Penaeus merguiensis in different combinations of temperature, light intensity and photoperiod 总被引:3,自引:0,他引:3
The combined effects of temperature (23 and 27 °C), light intensity (1100 and 2 lux or ≈ 21.5 and 0.04 μEinst m?2 s respectively) and photoperiod (10 h light/14 h dark and 14 h light/10 h dark) on ovarian maturation and spawning performance of ablated pond‐reared Penaeus merguiensis were investigated in a 51‐day experiment. The results showed that temperature was the most influential factor, followed by light intensity, whereas the effect of photoperiod was minor. As the maturation process progressed, the effects of temperature and light intensity became stronger while that of photoperiod became less significant. Temperature significantly affected all the reproductive parameters assessed. Prawns in the 27 °C treatments outperformed those in the 23 °C treatments (P < 0.05). The effect of light intensity was found to have a significant effect (P < 0.05) only on the proportion of spawners (prawns that spawned) and spawning rate. More prawns spawned at a higher rate under dim light (2 lux) than under strong light (1100 lux). Photoperiod affected only the proportion of prawns reaching stage III of ovarian development (P < 0.05). There were interactions between temperature and light intensity affecting the proportion of prawns reaching stage III and, although not significantly, the proportion of spawners (P = 0.177), fecundity (P = 0.134) and survival (P = 0.061). Overall, it is recommended that a combination of 27 °C, 2 lux and 10 h light/14 h dark is suitable for the maturation of pond‐reared P. merguiensis. There were indications that temperature can be used to control the rate of ovarian maturation. Also, it is possible to increase light intensity up to 1100 lux in P. merguiensis hatcheries if prawns are ablated. 相似文献
79.
Critical thermal minima (CTMin) were determined for subadults of Penaeus merguiensis acclimated at 15, 18, 21 and 24 °C for 3 weeks. The effect of cooling rate on CTMin was also investigated. The CTMin of prawns from these respective acclimation groups were 5.3, 6.0, 7.4, 9.0 and 4.7, 5.4, 6.0, 7.3 °C at the cooling rate of 1 °C h?1 and 3 °C h?1 respectively. Both acclimation temperature and cooling rate had a significant effect (P < 0.01) on the CTMin. Observation during the acclimation period showed that the growth rate of prawns acclimated at 24 °C was much higher than those acclimated at 21, 18 and 15 °C. The results indicate that P. merguiensis can overwinter in aquaculture ponds in south‐east Queensland, Australia, or other subtropical areas and attain good growth if simple overwintering facilities are available. 相似文献
80.
Chuong V. Huynh Nguyen Phuong T. Pham Tung G. Nguyen Hai T. Nguyen Mai T. H. Tran Phuong T. 《Eurasian Soil Science》2022,55(8):1041-1051
Eurasian Soil Science - We investigate the key predictors that influence the soil organic matter (SOM) content in higher altitude plantations. This is to study the potential of carbon sequestration... 相似文献