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271.
Correlations of calves’ temperament with carcass traits were estimated to clarify the genetic relationships between them in Japanese Black cattle. The temperament records for 3128 calves during auction at a calf market were scored on a scale of 1 (calm) to 5 (nervous) as temperament score (TS ), and the TS were divided into two groups (TSG ): TS 1 and 2 comprised TSG 1, and 3 to 5 constituted TSG 2. Carcass data were obtained from 33 552 fattened cattle. A threshold animal model was used for analyzing the underlying liability for TSG , whereas a linear one was used for TS and carcass traits. The heritability estimates for TS and TSG were 0.12 and 0.11, respectively. On the other hand, moderate to high heritability estimates were obtained for carcass traits (0.40 to 0.68). The temperament scores were negatively correlated with carcass weight, rib thickness and subcutaneous fat thickness (?0.13 to ?0.59). In contrast, weak to moderate positive correlations were found between the temperament scores and rib eye area or yield estimate (0.16 to 0.45). The temperament scores and beef marbling score had no correlation. These results showed that it is possible to improve temperament and carcass traits simultaneously.  相似文献   
272.
应用最优控制理论对拖拉机半挂车机组自动直线倒车行驶进行了研究.应用最优控制理论和线性化的车辆运动方程设计了拖拉机半挂车机组直线倒车的线性二次型控制器,运用控制器分别在沥青路面和未整修道路上进行了实车实验.实验表明,该控制方法能够实现拖拉机半挂车机组自动直线倒车行驶控制,且车辆的行驶速度对车辆系的横向偏差影响很大.  相似文献   
273.
The influence of the physicochemical properties of heat‐moisturetreated and untreated starches from various plant sources on the quality of tempura fried batter was examined. Batter of each starch plus wheat protein (92:8, w/w) was fried. Quality of the resulting fried batter was determined from crispness score, water evaporation, and breaking strength. The crispness score correlated with water evaporation (r = 0.95) and breaking strength (r = 0.97), indicating that water evaporation was a reliable index for evaluation of crispness of fried batter. Determination of water evaporation was easy and simple. The crispness (favorable eating texture) of tempura coating depended largely on starch origin. Among the pasting properties of starch, temperature at maximum viscosity (r = 0.77) and breakdown/maximum viscosity (% breakdown, r = ‐0.82) correlated with water evaporation, suggesting that starch resistant to gelatinization and granule disintegration produced crispy fried batter. This observation was supported by SEM. Water evaporation (r = ‐0.82) and % breakdown (r = 0.95) correlated with degree of amylose gelatinization, indicating that amylose was one of the determinants that controls crispness of fried batter by restraining disintegration of the starch granule structure.  相似文献   
274.
The molecular structure and pasting properties of starches from eight buckwheat cultivars were examined. Rapid viscograms showed that buckwheat starches had similar pasting properties among cultivars. The actual amylose content was 16–18%, which was lower than the apparent amylose content (26–27%), due to the high iodine affinity (IA) of amylopectin (2.21–2.48 g/100 g). Amylopectins resembled each other in average chain‐length (23–24) and chain‐length distributions. The long‐chains fraction (LC) was abundant (12–13% by weight) in all the amylopectins, which was consistent with high IA values. The amyloses were also similar among the cultivars in number‐average DP 1,020–1,380 with 3.1–4.3 chains per molecule. The molar‐based distribution indicated that all the amyloses comprised two molecular species differing in molecular size, although the weight‐based distribution showed a single species. A comparison of molecular structures of buckwheat starches to cereal starches indicated buckwheat amylopectins had a larger amount of LC, and their distributions of amylose and short chains of amylopectin on molar basis were similar to those of wheat and barley starches.  相似文献   
275.
Amylose and amylopectin were prepared from large, medium, and small granule starches of classified waxy barley flour, and their fine structures were investigated. The amylose content had a wide distribution range (≈1.4–9.4%). Number‐average degrees of polymerization (DPn) of the amyloses were similar among the samples (≈1,200–1,300). But number of chains per molecule (NC) decreased from the surface to the center (≈6–10 chains). DPn of the amylopectins varied from 4,657 to 14,604; decreased in the order of large, medium, and small granules in same fractions of the grain; and increased from the surface layer to the center. Longest chains (LC) were not found in any of the amylopectin molecules. The large amylopectin molecule had more long chains and fewer A chains than the small molecule. The amylose content had definite effects on the transition temperature range and crystal formation of the starch granules. There were positive correlations between DPn of the amylopectin and relative crystallinity (γ = +0.69) and enthalpy value (γ = +0.80), respectively. These findings may help to elucidate biosynthesis mechanism of starch.  相似文献   
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