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The effects of variety and growth location on grain composition and starch structures were investigated using three rice (Oryza sativa L.) cultivars (Phka Romduol, Sen Pidao and IR66) with different amylose contents. All the three cultivars were planted in three different agro-climatic zones (Phnom Penh, Coastal and Plateau) of Cambodia. The protein content of polished grains increased when rice was planted at a location with higher average temperature, but their lipid content decreased. The amylose content and degree of branching were not greatly affected by the minor temperature differences among the growing locations. Starch fine structures characterized by the chain-length distribution were significantly different among the cultivars, but not significantly among different locations. The results suggested that protein and lipid biosyntheses were more sensitive to the environmental temperature than that of starch in rice grains. 相似文献
3.
刘湛 《农业机械化与电气化》2014,(6):20-23
铁西区通过打造装备制造业产业聚集区。形成了高档数控机床、通用石化装备等六大主导产业以及电气及新能源等五大千亿产业集群,成为我国老工业基地振兴的区域典范。介绍铁西装备制造业聚集区发展现状,采用区位熵法测算沈阳装备制造业的产业集中度,对全市装备制造业的现状及问题进行分析,得出相应结论。 相似文献
4.
Effects of cover crop growth and decomposition on the distribution of aggregate size fractions and soil microbial carbon dynamics 下载免费PDF全文
D. Linsler M. Kaiser R. Andruschkewitsch C. Piegholdt B. Ludwig 《Soil Use and Management》2016,32(2):192-199
Although the effects of cover crops (CC) on various soil parameters have been fully investigated, less is known about the impacts at different stages in CC cultivation. The objective of this study was to quantify the influence of CC cultivation stages and residue placement on aggregates and microbial carbon (Cmic). Additionally, the influence of residue location and crop species on CO2 emissions and leached mineralized nitrogen (Nmin) during the plant degradation period was also investigated. Within an incubation experiment, four CC species were sown in soil columns, with additional columns being kept plant‐free. After plant growth, the columns were frozen (as occurs in winter under field conditions) and then incubated with the plant material either incorporated or surface‐applied. With CC, concentrations of large and medium macroaggregates were twice that of the fallow, confirming positive effects of root growth. Freezing led to a decrease in these aggregate size classes. In the subsequent incubation, the large macroaggregates decreased far more in the samples with CC than in the fallow, leading to similar aggregate size distributions. No difference in Cmic concentration was found among the CC cultivation stages. CO2 emissions were roughly equivalent to the carbon amounts added as plant residues. Comparison of columns with incorporated or surface‐applied residues indicated no consistent pattern of aggregate distribution, CO2 emission or Cmic and Nmin concentrations. Our results suggest that positive effects of CC cultivation are only short term and that a large amount of organic material in the soil could have a greater influence than CC cultivation. 相似文献
5.
Zandvliet MM Rothuizen J 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(2):215-218
BACKGROUND: Irish Wolfhounds frequently have a congenital portosystemic shunt, but a considerable proportion of the 6- to 8-wk-old pups has hyperammonemia in the absence of portosystemic shunting. This hyperammonemia causes no signs and is transient, normalizing at the age of 3-4 months. HYPOTHESIS: Transient hyperammonemia has a metabolic basis in Irish Wolfhounds. ANIMALS: Two related (same sire) litters of Irish Wolfhounds (17 pups) and their parents were studied. METHODS: Integrity of the portal circulation was examined by ultrasonography and scintigraphy. Absence of parenchymal liver disease was verified by liver biopsy. Amino acid profiles were measured in 4 pups and repeated in 2 of these pups when ammonia concentrations had normalized. The amino acid profiles were compared with those of healthy Irish Wolfhound pups. RESULTS: Fasting venous ammonia concentrations were high (113-622 microg/dL, 65-345 micromol/L) in all pups, whereas bile acids were within reference range in all but 1. The ammonia and bile acid concentrations from all parents were within reference range. Portosystemic shunting was excluded in all but 1 pup. Liver biopsy excluded significant lesions in all 10 pups examined. Hypercitrullinemia was found and persisted even when ammonia had normalized, at the expense of an increase in glutamine and asparagine. CONCLUSIONS AND CLINICAL IMPORTANCE: Citrulline concentrations are controlled by the urea cycle enzymes argininosuccinase and argininosuccinate synthetase, and a defect in either of these enzymes may be responsible for the transient hyperammonemia in Irish Wolfhounds. Resolution of the hyperammonemia is associated with increased activity of alternative metabolic pathways forming glutamine and asparagine. Confirmation requires measurement of enzyme activities in liver tissue. 相似文献
6.
A 5-year-old Oldenburg mare presented for poor performance, head-tossing and bucking when ridden. An abnormal respiratory noise was audible during exercise. Computed tomography (CT) revealed right laryngeal dysplasia; an absent cricothyroid articulation, abnormally shaped thyroid cartilage, underdeveloped cricopharyngeus muscle, rostral displacement of the palatopharyngeal arch and an oesophageal air column. In this case, it was unlikely that the laryngeal pathology was related to the horse's clinical signs. This case report provides a reference CT examination of laryngeal dysplasia, corroborating previous findings using magnetic resonance imaging, radiography, ultrasonography and post-mortem examination. 相似文献
7.
YANG Zhong-ren RAO Cheng ZOU Jian PENG Zhen-liane Ministry of Education Chongqing Chin 《保鲜与加工》2004,(2):32-35
Dong village is very valuable for research work because of its special regional and national character and rich cultural implication. In this paper, some information about the location, form and features of Dong village is given. Then, the relationship between the culture and the settlement is analyzed, which provides a clue for understanding Dong village and will be beneficial to creating modern human settlements. 相似文献
8.
The damage of bridge cable directly hazards the normal use of bridge and the safety of people. The paper discussed the signal acquisition and detection system which takes embedded DSP processor as core technology, combined with CCD, video decode chip, SDRAM, FLASH ROM, and established the fast measuring algorithm of the surface corrosion and damage, which includes deteminating the processing region, improving medium filter, sobel edge detection and dynamic threshold segment, close operation of morphology, computing defect area and saving. The experimental resuits show that this method implemented the real-time, non-contact and intelligence detecting of cable surface defect and gives the specifications of the system. 相似文献
9.
农村居民点整治工程选址适宜性评价与决策 总被引:1,自引:2,他引:1
[目的]通过对影响农村居民点整治工程选址适宜性的指标因素进行分析,构建农村居民点整治工程适宜性评价体系。[方法]引入配对比较法和1—7标度理论法确定指标因素权重,通过综合分值测算法对农村居民点整治工程适宜性进行评价。根据离散度分析法对适宜性综合分值进行级别划分。[结果]河北省唐县农村居民点整治工程选址适宜性可划分为4等,即适宜区、较适宜区、一般适宜区和不适宜区,其综合作用分值划分区间为:77分以上为适宜区,68.59~77分为较适宜区,61.37~68.59分为一般适宜区,61.37分以下为不适宜区。[结论]相关部门应谨慎决策选址的时空顺序,有效提高农村居民点整治工程选址的科学性和可行性。 相似文献
10.
自然环境下葡萄采摘机器人采摘点的自动定位 总被引:1,自引:15,他引:1
针对葡萄果梗颜色复杂多变、轮廓不规则等影响因素使得采摘机器人难以准确对采摘点进行定位的问题,该文提出一种基于改进聚类图像分割和点线最小距离约束的采摘点定位新方法。首先通过分析葡萄图像的颜色空间,提取最能突显夏黑葡萄的HSI色彩空间分量H,运用改进的人工蜂群优化模糊聚类方法对葡萄果图像进行分割;然后对分割图像进行形态学去噪处理,提取最大连通区域,计算该区域质心、轮廓极值点、外接矩形;再根据质心坐标与葡萄簇边缘信息确定采摘点的感兴趣区域,在区域内进行累计概率霍夫直线检测,求解所有检测得出的直线到质心之间的距离,最后选取点线距离最小的直线作为采摘点所在线,并取线段中点坐标作为采摘点。以从晴天顺光、晴天遮阴、阴天光照下采集的300幅夏黑葡萄进行分类试验,结果表明,该方法的采摘点定位准确率达88.33%,平均定位时间为0.3467 s,可满足采摘机器人对采摘点的定位需求,为葡萄采摘机器人提供了一种新的采摘点求解方法。 相似文献