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1.
Soybean oil hydrogenation alters the linolenic acid molecule to prevent the oil from becoming rancid, however, health reports have indicated trans-fat caused by hydrogenation, is not generally regarded as safe. Typical soybeans contain approximately 80 g kg−1 to 120 g kg−1 linolenic acid and 240 g kg−1 of oleic acid. In an effort to accommodate the need for high-quality oil, the United Soybean Board introduced an industry standard for a high oleic acid greater than 750 g kg−1 and linolenic acid less than 30 g kg−1 oil. By combing mutations in the soybean plant at four loci, FAD2-1A and FAD2-1B, oleate desaturase genes and FAD3A and FAD3C, linoleate desaturase genes, and seed oil will not require hydrogenation to prevent oxidation and produce high-quality oil. In 2017 and 2018, a study comparing four near-isogenic lines across multiple Tennessee locations was performed to identify agronomic traits associated with mutations in FAD3A and FAD3C loci, while holding FAD2-1A and FAD2-1B constant in the mutant (high oleic) state. Soybean lines were assessed for yield and oil quality based on mutations at FAD2-1 and FAD3 loci. Variations of wild-type and mutant genotypes were compared at FAD3A and FAD3C loci. Analysis using a generalized linear mixed model in SAS 9.4, indicated no yield drag or other negative agronomic traits associated with the high oleic and low linolenic acid genotype. All four mutations of fad2-1A, fad2-1B, fad3A, and fad3C were determined as necessary to produce a soybean with the new industry standard (>750 g kg−1 oleic and <30 g kg−1 linolenic acid) in a maturity group-IV-Late cultivar for Tennessee growers.  相似文献   
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A solution to autonomous lateral vehicle guidance using a neurocontroller that can learn from measured human-driving data without knowledge of the physical car parameters is discussed. Simulations and practical tests confirm that a small-size feedforward autonomous neural network (21 neurons) can learn to steer a vehicle at high speeds only from looking at human-driving examples. In this way, the network learns the total closed-loop behavior, including the nonlinear dynamics of the vehicle and the driver's individual driving style. The main result of practical investigations is that the neutral controller trained on human-driving examples exhibits an aperiodic behavior that does not vanish at higher speeds (tests performed up to 130 km/h) and produces fewer lateral deviations than the linear state controller  相似文献   
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Zusammenfassung Ziel des Teilvorhabens, über das hier berichtet wird, was es, für eine Auswahl von physikalischen Effekten eine Zuordnung von gestaltbeeinflussenden Merkmalen auf sehr abstrakter Ebene zu erreichen und damit eine n?here Charakterisierung der Wirkfl?chen und Wirkr?ume zu erreichen die zur Umsetzung eines physikalischen Effektes notwendig sind. Die hieraus resultierenden Ergebnisse sind dem Abschlu?bericht zu entnehmen [1]. Weiterführende Themen, die basierend auf den vorliegenden Erkenntnissen bearbeitet werden, haben zum Ziel, die wesentlichen und entscheidenden Parameter einer Konstruktionsaufgabe zu erkennen und zukünftig zielgerichtet L?sungsvarianten zu erstellen, um somit für eine Neukonstruktion sinnvolle L?sungsfelder sehr frühzeitig abzugrenzen.  相似文献   
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This paper describes a design for an analog phase shifter operating at 915 MHz and suitable for use in a phased array microwave hyperthermia system. Here, the major operating constraint was minimization of amplitude variation over a 1800 phase shift, whereas previous phase shifters were designed to obtain a linear relationship between phase and control voltage. The result is a simple, inexpensive hybrid coupler phase shifter that operates over a narrow bandwidth and provides 180°of continuous phase shift with input powers up to 1 W.  相似文献   
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INTRODUCTION: In a retrospective study a treatment concept for Perthes' disease dependent on the containment was applied. PATIENTS/METHODS: 49 hips of 41 children (9 female, 32 male) were treated between 01. 01. 1990 and 31. 12. 1995. In our concept of treatment a varus femoral osteotomy was performed in 28 cases with not contained hips or less than 4/5 coverage of the femoral head (X-ray/MRI). The other 21 well contained hips with 4/5 coverage or more were treated conservatively with physiotherapy and in case of joint effusion and pain additionally with the use of crutches (partial weight bearing) and anti-inflammatory medication. The average age in the non-operative group at the time of first investigation was 4 years and 9 months (3 y./1 m. to 7 y./1 m.) and 6 years and 3 months (4 y/2 m. to 10 y/0 m.) at our last examination (mean follow up 17.7 months, range of 6 to 72 months). At the time of indication for a varus femoral osteotomy the patients had an average age 6 years and 1 month (3 y./6 m. to 10 y./2 m.), the mean age at the last postoperative examination was 7 years and 11 months (4 y./8 m. to 12 y./5 m.) with an average follow up of 21.5 months (6 to 77 months). RESULTS: For the conservatively treated children we achieved good results (still well contained hips with 4/5 coverage, no decrease of function, no increase of pain) in 85.7% (18 of 21 cases). In 85.7% (24 of 28 cases) we found good results (well contained hips, increase of coverage, no decrease of function, no increase of pain) in the operation group. CONCLUSIONS: The presented concept of therapy in Perthes' disease was practicable for all patients and included the possibility of decision for operative or non-operative treatment. In both groups we achieved good results in 85.7% of the cases.  相似文献   
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Kindergartners, 3rd, and 6th graders chose classmates whom they would and would not like to have on their team for an academic contest and as playmates. Ss also rated their classmates on likableness and academic ability. At all ages, children's choices for the academic competition and the play situation were significantly associated with their ratings of their classmates' academic and social competence, respectively. Ss typically referred to academic abilities to explain their teammate choices for the academic contest and to social competence or friendship to explain playmate choices. Questions about the stability of classmates' academic and social competencies revealed that not until 6th grade did Ss indicate that there are limits in the degree to which academic and social competencies could improve with effort. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The improved fracture resistance of whisker-reinforced ceramic-matrix composites involves more than one energy-absorbing mechanism. The possible mechanisms are reviewed and a micromechanical model evaluating the relative contributions to the overall toughness is presented. The mechanisms involve microcracking, load transfer, bridging, and crack deflection. The synergism of these mechanisms is examined using an energy release rate balance equation. The basic assumption of the proposed model is that the load transfer between the matrix and the whiskers is due to Coulomb friction. The model has been applied to an Al2O3/SiC whisker composite and shows reasonable agreement with reported experimental results. The role of the thermal residual stresses is also examined in light of the frictional load transfer assumption.  相似文献   
10.
The United States has historically excelled in the design of products, processes and new technologies. Capitalizing on this historical strength to teach applied mathematics and science has many positive implications on education. First, engineering design can be used as a vehicle for addressing deficiencies in mathematics and science education. Second, as achievement in mathematics and science is enhanced, a greater number of students at an earlier age will be exposed to technical career opportunities. Third, enhancing elementary and secondary curricula with engineering design can attract underrepresented populations, such as minorities and females, to engineering as a profession. This paper describes a new and innovative engineering design curriculum, under development in the Austin Independent School District (AISD) in Austin, TX. The philosophic goals upon which the curriculum is based include: integrating the design problem-solving process into elementary schools, demonstrating the relationship of technical concepts to daily life, availing teachers with instructional strategies for teaching applied (as opposed to purely theoretical) science and mathematics, and teaching teamwork skills that are so greatly needed in industry and everyday life. Based on these goals, kindergarten, first grade, and second grade engineering design lessons have been piloted in AISD, in conjunction with a University of Texas program for teacher enhancement and preparation.  相似文献   
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