Relationship between Bran Mechanical Properties and Milling Behaviour of Durum Wheat (Triticum durum Desf.). Influence of Tissue Thickness and Cell Wall Structure

Eight durum wheat samples, including four varieties grown in different environments, were employed in an investigation on the influence of mechanical properties of bran on milling behaviour. The anisotropic nature of bran due to the particular structure of the outer epidermis of the pericarp required investigation of its mechanical properties in two grain orientations. Rheological characteristics (strain and linear force to rupture, rigidity modulus and rupture energy) were determined using traction tests performed on isolated bran strips. The results revealed significant variability between samples with significant effects of wheat variety and crop site. Influences of tissue thickness on bran rigidity (E′), and the degree of arabinoxylan (AX) cross-linking in cell walls on bran strength and extensibility, respectively, were demonstrated. A strong influence of tissue extensibility on the degree of bran contamination of semolina generated during the milling process was established statistically.     

高职院校推进全学科课程思政建设路径探究——以北京农业职业学院贯通培养项目基础文化课学段为例

课程思政通过挖掘、提炼课程中所蕴含的思想政治元素,将思想政治教育融入到教学中,潜移默化地实现育人功能.北京农业职业学院全面推进课程思政建设,在高端技术技能人才贯通培养实验项目基础文化课学段的所有课程中实施课程思政,经过不断探索和实践,在深化教师"三全育人"理念、推动师德师风建设、提升学生思想政治教育效果等方面收到了显著成效.为进一步强化课程思政建设,积极研究创新路径,在强化价值引领、创新课程思政教育模式、成果固化等方面提出建议,以更好地推进思想政治教育工作,确保贯通培养项目的持续发展.     

广西大学图书馆新馆建设——结构、布局和服务功能

论述了在集藏、借、阅、检、管于一体化,这一先进的管理模式下,新馆建设在结构上应充分注意3点:应采用同层高、同柱网、同荷载的先进设计理念;应充分重视卫生、环保、节能;应注意防火安全。在布局上应合理规划多功能区、读者服务区、行政办公区,使读者流、工作人员流、物流各行其道,互不干扰。提出了"图书馆工作人员和读者之间,双方的人文关怀"这一新的理念。道出了"我为人人,人人为我,方便别人就是方便自己"这样一个做人的简单的道理。     

Effect of endosperm starch granule size distribution on milling yield in hard wheat

Increased flour yield in hard wheat is associated with increased endosperm rheology index, calculated from strength and stiffness as measured by the SKCS. A study of the fractured endosperm of hard wheat varieties grouped according to similar rheology index values was performed using environmental scanning electron microscopy (ESEM). Differing microstructures and fracture patterns were observed between each group. Specifically, the group representing high rheology index had a greater concentration of small starch granules in prismatic cells. Samples of diverse wheat germplasm were grown at two sites and subjected to laboratory milling. Starch granule size distribution (SGSD) analysis using a laser diffraction method was undertaken on a subset of samples in triplicate representing a range in flour yield. The results supported an hypothesis for a significant influence of SGSD on flour yield of hard wheat varieties. In addition, a significant part (R²>0.40 (p<0.05) at two sites) of the association appeared to be under genetic control. Results indicate a more even gradation of distributions involving an increase in the sample volume % of small granule (types B and C) and decrease in type A granules. This was associated with increased rheology index values and higher flour yield. The ratio of type A:C starch granules accounted for up to 58% (p<0.05) of the variation in flour yield in the samples studied. Thus, rheological parameters measured using a rapid SKCS screening method can be linked to the genetic regulation of SGSD with implications for the improvement of commercial processing performance of hard wheat.     

Comparison of predictions of baking volume using large deformation rheological properties

Three large deformation rheological tests, the Kieffer dough extensibility system, the D/R dough inflation system and the 2 g mixograph test, were carried out on doughs made from a large number of winter wheat lines and cultivars grown in Poland. These lines and cultivars represented a broad spread in baking performance in order to assess their suitability as predictors of baking volume. The parameters most closely associated with baking volume were strain hardening index, bubble failure strain, and mixograph bandwidth at 10 min. Simple correlations with baking volume indicate that bubble failure strain and strain hardening index give the highest correlations, whilst the use of best subsets regression, which selects the best combination of parameters, gave increased correlations with R²=0.865 for dough inflation parameters, R²=0.842 for Kieffer parameters and R²=0.760 for mixograph parameters.     

直立与弯曲穗型水稻穗上不同部位籽粒碾磨品质的比较

以直立穗型和弯曲穗型水稻材料为对象,研究了穗上不同部位和不同粒位籽粒在碾米品质上的差异。弯曲穗型材料整穗籽粒的糙米率、精米率及整精米率以及粒重均高于直立穗型材料,其中整精米率差异达到显著水平。总体而言,在稻穗的同一部位,两穗型材料一次枝梗籽粒的糙米率、精米率、整精米率和粒重均高于二次枝梗的籽粒;一次枝梗上以第2 或第3粒位籽粒的糙米率、精米率和整精米率较高,第1 粒位籽粒的较低;穗上同一部位二次枝梗籽粒的碾米品质在两穗型材料间的差异大于一次枝梗,而穗型与其排序并无直接关系;两穗型材料籽粒粒重在穗上的分布与排序基本一致。因此,可以通过育种选择来改良直立穗型材料的碾磨品质。     

不同硼效率油菜品种细胞壁组分中硼的分配

应用不同硼效率甘蓝型油菜品种(Brassica napus),研究硼在细胞壁各组分中的分配规律。结果表明,细胞壁硼主要结合在果胶中,根系细胞壁80%以上的硼、叶片细胞壁95%以上的硼结合在果胶中。叶片细胞壁果胶硼含量高于根系细胞壁。品种间细胞壁各组分硼含量存在差异,低效品种苗期叶片中螯合剂可溶性果胶硼含量显著高于高效品种     

禾顶囊壳小麦变种对小麦种子根的侵染过程

 光镜和电镜观察表明,禾顶囊壳小麦变种(Gaeumannomyces graminis var.tritici,小麦全蚀病菌)对小麦种子根的侵染过程可分为侵入前、侵入表皮层、进入皮层和进入中柱等4个连续阶段。麦根接菌后在15℃下培养,48 h后侵入表皮层细胞,60 h后进入皮层,120 h后进入中柱。病原菌主要以侵染菌丝直接侵入表皮层,表皮细胞间隙和根毛基细胞是主要侵入部位,少数由附着枝侵入。菌丝穿透细胞壁有明显的酶解作用特征,菌丝先端前方胞壁上还产生电子密物质。皮层细胞是病原菌定殖和发展的主要场所,病原菌还能离解胞间层,形成胞外空间,特别有利于菌丝和菌丝束的扩展。在侵入位点的寄主细胞壁和质膜之间,形成多种形状的木质管,其数量与侵入菌丝的数目相对应,但木质管不能阻止菌丝进入细胞。菌丝进入中柱后,可阻塞导管和筛管。小麦细胞发生退行性病变,尤以细胞壁膨大崩坏和早期质壁分离最明显,细胞间隙还产生性质不明的黄色物质。     

县级农田水利化管理质量的AHP评价方法

本文对影响县级农田水利化管理系统质量的影响因素进行系统分析 ,建立了综合评价县级农田水利化系统管理质量的层次分析模型 ,确定了农田水利化系统管理质量综合评价步骤和方法 .为县级农田水利化管理质量的评价提供科学的决策方法     

小尾寒羊在陕北地区适应性能的综合评价

对从鲁西南地区引入陕北的小尾寒羊在两地的生产性能,生理生化反应和抗逆抗病性等综合性能进行了测试和对比分析。结果表明,该羊种在陕北地区的表型适应和遗传适应均表现良好,可以作为当地的适应良种引入,但在引种上要选择适宜的季节和种羊日龄,并在风土驯化方面要注重防治羊流感为主的呼吸系统疾病。