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61.
62.
Six high protein and high lysine barley lines were derived from four crosses involving high protein andlor high lysine donors, ie Riso 1508 and SV 73608 (Hiproly×Mona5), with well adapted local strains V 5681 and V 4342. The trial was grown at the Wheat Research Institute, Faisalabad, Pakistan. The lines were chemically and nutritionally characterized and the results were compared with the parents. The biological value, net protein utilization and lysine contents were higher in all the derived lines than in their local parents, ie V 5681 and V 4342. The increased lysine levels in the lines B 82503 and B 82507 may be a consequence of the reduction of prolamin fractions with simultaneous increases in salt soluble fractions. In all the lines, lysine and nutritional quality increase were a reflection of high protein andlor high lysine parents. The line B 82503 had grain yield comparable to its local parent V 5681 but it was superior in lysine and some nutritional attributes to its high lysine donor parent Riso 1508. In some lines, lysine improvement was achieued without impairing grain yield.  相似文献   
63.
Bovine-ejaculated sperm were washed thrice in bovine serum albumin-saline media, pH 7.2 to 8.4, and incubated at 37 degrees C in Ca++-free Tyrode's media. pH 7.2 to 8.4, for 0, 2, 4, 6, and 8 h. Motility was highest when sperm were washed in pH 7.2 medium and incubated in pH 8.0 or 8.4 media. Motility remained above 50% until 8 h. Washing in pH 7.6, 8.0, or 8.4 media induced more acrosome reactions after incubation than washing at pH 7.2. Percentage of acrosome-reacted sperm increased at each successive time period. Sperm penetrated more oocytes at 4, 6, and 8 h when wash medium pH was fixed at 7.2 and capacitating media pH was raised at .4 unit increments from 7.2 to 8.4. When sperm were washed in pH 7.2 medium, the postincubation penetration rates peaked at 8 h. With wash media of pH 7.6, 8.0, or 8.4, the postincubation penetration rates peaked at 4 h and then gradually declined. In conclusion, the most effective system for capacitating bull sperm was a pH 7.6 wash followed by capacitation in pH 7.6 medium for 4 to 8 h and this system resulted in the highest penetration rates. Wash media pH hastened capacitation but was not a capacitating agent.  相似文献   
64.
Coronary artery ectasia (CAE) is frequently encountered in clinical practice, conjointly with atherosclerotic CAD (CAD). Given the overlapping cardiovascular risk factors for patients with concomitant CAE and atherosclerotic CAD, a common underlying pathophysiology is often postulated. However, coronary artery ectasia may arise independently, as isolated (pure) CAE, thereby raising suspicions of an alternative mechanism. Herein, we review the existing evidence for the pathophysiology of CAE in order to help direct management strategies towards enhanced detection and treatment.  相似文献   
65.
We hypothesized that conjugation of the near-infrared dye MHI-148 with the anti-leukemia drug dasatinib might produce a potential theranostic for glioblastoma. In fact, the conjugate was found to bind the kinases Src and Lyn, and to inhibit the viability of a glioblastoma cell line with significantly greater potency than dasatinib alone, MHI-148 alone, or a mixture of dasatinib and MHI-148 at the same concentration. It was also used to successfully image a subcutaneous glioblastoma tumor in vivo.  相似文献   
66.
Exercise can improve health and well-being. With this in mind, immersive virtual reality (VR) games are being developed to promote physical activity, and are generally evaluated through user studies. However, building such applications is time consuming and expensive. This paper introduces VR-Rides, an object-oriented application framework focused on the development of experiment-oriented VR exergames. Following the modular programming pattern, this framework facilitates the integration of different hardware (such as VR devices, sensors, and physical activity devices) within immersive VR experiences that overlay game narratives on Google Street View panoramas. Combining software engineering and interaction patterns, modules of VR-Rides can be easily added and managed in the Unity game engine. We evaluate the code efficiency and development effort across our VR exergames developed using VR-Rides. The reliability, maintainability, and usability of our framework are also demonstrated via code metrics analysis and user studies. The results show that investing in a systematic approach to reusing code and design can be a worthwhile effort for researchers beyond software engineering.  相似文献   
67.
Wireless Personal Communications - In this work, we propose a new and efficient algorithm to mitigate the signal look direction error problem in adaptive beamforming without broadening the main...  相似文献   
68.
Wireless Networks - Cognitive radios and femtocell networks are gaining much popularity due to the formers ability to carry out unlicensed transmission in licensed bands and the latter’s...  相似文献   
69.
70.
On the Handling of Continuous-Valued Attributes in Decision Tree Generation   总被引:16,自引:0,他引:16  
We present a result applicable to classification learning algorithms that generate decision trees or rules using the information entropy minimization heuristic for discretizing continuous-valued attributes. The result serves to give a better understanding of the entropy measure, to point out that the behavior of the information entropy heuristic possesses desirable properties that justify its usage in a formal sense, and to improve the efficiency of evaluating continuous-valued attributes for cut value selection. Along with the formal proof, we present empirical results that demonstrate the theoretically expected reduction in evaluation effort for training data sets from real-world domains.  相似文献   
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