热杀菌条件对NFC冬枣汁成分及抗氧化活性的影响研究

为了研究不同热杀菌条件对NFC冬枣汁理化性质、活性成分及抗氧化活性的影响,本文以冬枣为研究对象,设置了低温长时杀菌(75℃,5、10、15、20、25 min)和高温短时杀菌(90℃,0.25、0.50、0.75、1.00、1.50 min)两个处理,考察了NFC冬枣汁的可溶性固形物含量、pH值、总酸含量、VC含量、DPPH清除率、亚铁离子还原率等指标。研究结果表明,两种杀菌方式对NFC冬枣汁基本理化性质影响不显著(P>0.05)。相比于低温长时杀菌,高温短时杀菌的△E值更低,更能保持冬枣汁原有的色泽。两种杀菌处理后多酚、VC含量均显著降低(P<0.05),低温长时杀菌25 min后VC含量未检出,抗氧化活性也显著低于高温短时杀菌(P<0.05)。因此,通过对NFC冬枣汁品质变化的分析,发现高温短时杀菌能更好地保持原有的色泽和营养成分。     

村务管理专业学生的教育管理研究

随着国家乡村振兴战略的深入实施,村务管理专业学生招生规模迅速扩大,教育管理对乡村振兴发展、学院建设、个人成长具有重要意义.从分析学生的特点和教育管理现状入手,阐述了抓好村务管理专业学生教育管理的重要意义,提出把好招考入学、教书育人、考察使用关口,做好学院内部与外部管理结合、教育管理与精准服务结合、依法依规与沟通交流结合、教育引导与更新观念结合、宣传表彰与惩戒警示结合,加强学生的教育管理工作.     

茶树花青素形成分子机理的研究进展

花青素是由类黄酮合成途径产生的次生代谢产物,含量高时会使茶树新梢呈现红色或紫色。同时,花青素相比儿茶素等具有更明显的抗氧化、预防肿瘤等药理保健作用。文章就茶树花青素合成途径、转录及转录后调控等方面进行综述,以期更好地为高花青素茶树的育种研究提供理论依据。     

TCD燃烧系统对柴油机燃烧和排放性能改善效果的试验研究

为探究道依茨TCD2015柴油机上配备的导流燃烧系统(简称TCD燃烧系统,T表示涡轮增压器,Turbocharger,C表示进气中冷,Charge air cooling,D为柴油颗粒捕集器,Diesel particle filter)对改善柴油机燃烧性能和降低污染物排放的效果,采用单缸机试验对TCD燃烧系统在不同转速、负荷和过量空气系数下的燃烧和排放性能进行研究。试验结果表明不同工况下TCD燃烧系统燃油消耗率和Soot排放量均低于传统ω燃烧系统,燃油消耗率最大降幅为7.01%,Soot排放量最大降幅为86.67%,且低过量空气系数(1.2～1.6)下TCD燃烧系统仍具有较好的性能。为揭示TCD燃烧系统改善油气混合促进燃烧的机理,采用AVL Fire软件建立了柴油机性能仿真模型。计算结果表明,TCD燃烧系统的环状凸起结构将燃油导向内外两室,从而促进了缸内燃油发展过程,燃油当量比大于4的浓混合气区域燃油质量比例相比ω燃烧系统降幅最大为9.75%,活塞下移时TCD燃烧系统内油束撞击浅盘侧壁形成撞壁射流扩大了燃油扩散面积,从而改善了缸内油气混合质量,燃油当量比小于1的均匀混合气区域燃油质量比例相比ω燃烧系统降幅最大为7.45%,因此TCD燃烧系统能够有效改善柴油机的燃烧和排放性能,可应用于柴油机高负荷和低过量空气系数工况综合性能提升。研究结果可为柴油机燃烧系统开发和改进提供参考。     

Agrobacterium-mediated transformation of the CrDAT gene and selection of transgenic periwinkle lines with a high vincristine accumulation

Catharanthus roseus contains vincristine and vinblastine, which are outstanding drugs for cancer. In the biosynthetic pathways of terpenoid indole alkaloids (TIAs) in C. roseus, deacetylvindoline 4-O-acetyltransferase (DAT) is a key enzyme that catalyses the last reaction of vindoline biosynthesis to form vinblastine and vincristine. In this study, the CrDAT transgene was transferred into the periwinkle by Agrobacterium-mediated transformation and generated transgenic periwinkle lines with an increase in vincristine accumulation. The C. roseus DAT gene was introduced into C. roseus plants and it was confirmed that CrDAT was successfully transferred into the genome of periwinkle plants and efficiently translated to synthesise recombinant DAT protein. Four transgenic periwinkle lines in T1 generation, T1-1, T1-3, T1-6, and T1-7, expressed recombinant DAT protein with the total protein content in the range of 2.86 μg.mg^?1 to 5.12 μg.mg^?1. Moreover, the vincristine contents of four transgenic lines increased by 1.63?2.48-fold compared to non-transgenic plants, ranging from 6.91 µg.g^?1 (fresh weight) to 10.53 µg.g^?1 (fresh weight). The T1-1 line had the highest vincristine content. Hence, the overexpression of the recombinant DAT protein can improve the vincristine accumulation of transgenic C. roseus plants.

Abbreviation: CrDAT - Catharanthus roseus Deacetylvindoline-4-O-Acetyl Transferase; D4H - Deacetoxyvindoline 4-hydroxylase; ELISA - Enzyme-Linked Immunosorbent Assay Monoterpene indole alkaloid; T0, T1 - Generations of transgenic plants; TIAs - Terpenoid indole alkaloids; WT- The wild-type tobacco plants (non transgenic plant); 35S - Cauliflower mosaic virus 35S promoter     

浙江安吉县实施毛竹收购价格指数保险的实践

近年来，随着劳动力工资水平的快速提高以及一系列严格的环保政策的出台，浙江安吉县毛竹收购价格持续走低并在较长时期处于低价徘徊，直接影响了竹农的经济收入和生产管理的积极性，出现了毛竹林抛荒失管现象。为保障竹林经营者的基本收益，扶持竹产业健康持续发展，安吉县探索实施了毛竹收购价格指数保险措施。文章介绍了安吉县毛竹收购价格指数保险的提出、方案设置以及实施2年来的实践情况，探讨了该保险所发挥的作用，提出了进一步改进的建议。     

vvi-miR160s介导VvARF18应答赤霉素调控葡萄种子的发育

【目的】研究vvi-miR160家族（vvi-miR160s）及其靶基因在‘魏可’葡萄种子发育过程中的作用,探究其应答赤霉素（GA）调控葡萄果实无核的潜在机理。【方法】采用miR-RACE、生物信息学分析、RT-qPCR、RLM-RACE等方法,鉴定vvi-miR160家族成员及其靶基因,分析vvi-miR160s及其靶基因应答GA的时空表达模式及其潜在功能。【结果】花前GA处理强烈抑制‘魏可’葡萄胚珠及种子发育,高效诱导其无核,且无核率达99.8%。克隆鉴定了VvMIR160s前体基因序列（501 bp）及成熟体序列,且它们在不同物种间具有较高的保守性;基于vvi-miR160s序列,预测到靶基因VvARF18,利用RLM-RACE技术检测到vvi-miR160s对VvARF18的裂解位点在第10和第11位之间,裂解频度9/17,证明VvARF18是vvi-miR160s的真实靶基因。该靶基因编码683个氨基酸,在398—411位存在核定位信号,且该蛋白亚细胞定位于细胞核上。VvARF18与其他物种间序列的同源保守性较高,基因结构相似,其中VvARF18蛋白与茶、烟草、梅花等物种亲缘关系较近。VvARF18启动子中包含4种作用元件,且含有较多激素相关元件。RT-qPCR结果显示,随着葡萄果实的发育,vvi-miR160c/d/e呈现‘V’形表达趋势,在硬核种子发育期表达较低,而VvARF18表现出与前者相反的表达趋势,在硬核种子发育期呈现高表达,表明vvi-miR160c/d/e对VvARF18负调控,但vvi-miR160a/b与VvARF18表达水平却不存在明显负相关。GA处理极显著地上调了vvi-miR160a/b在葡萄硬核种子发育期的表达,同时也显著抑制了VvARF18在同时期的表达,且它们的表达水平呈负相关,表明GA处理促进了vvi-miR160a/b对VvARF18的负调控作用;相反,GA减弱了vvi-miR160c/d/e对VvARF18的负调控作用。【结论】在vvi-miR160家族中,vvi-miR160c/d/e可能介导VvARF18在葡萄种子发育的特定阶段调控种子的发育形成,而vvi-miR160a/b可能主要介导VvARF18参与调控GA诱导葡萄种子败育的过程。     

Suramin alleviates hypertrophic scar in mice by inhibiting fibroplasia and inflammatory response

AIM: To investigate the therapeutical effect of suramin on hypertrophic scar (HPS) and its mechanism. METHODS: After the mouse model of HPS was established by mechanical stretching, the suramin solution at low dose (5 mg/kg) and high dose (10 mg/kg) was applied onto the scar site caused by mechanical load in mice by transdermal administration once a day for 10 d. The degree of scar hyperplasia was observed by macroscopy. The scar cross-sectional area and scar elevation index in the HPS tissues were evaluated by hematoxylin-eosin (HE) staining. The expression levels of transforming growth factor-β1 (TGF-β1) and interleukin-6 (IL-6) in HPS tissues were detected by immumohistochemical staining. The expression level of α-smooth muscle actin (α-SMA) in HPS tissues was detected by immunofluorescence staining, RT-qPCR and Western blot. The levels of tumor necrosis factor-α (TNF-α), IL-6, IL-10 and TGF-β1 in the HPS tissues were measured by ELISA. RESULTS: Macroscopic observation showed that the surface areas of scar in the HPS mice after treatment with suramin at low and high doses were significantly reduced (P<0.01). HE staining results showed that the scar cross-sectional area and the scar elevation index of HPS mice after treatment with suramin at low and high doses were significantly reduced (P<0.05 or P<0.01). The results of immunofluorescence staining, RT-qPCR and Western blot showed that the number of α-SMA positive cells and the mRNA and protein expression of α-SMA in scar tissues of HPS mice after treatment with suramin at low and high doses were significantly decreased (P<0.05 or P<0.01). The results of immunohistochemical staining showed that the expression levels of TGF-β1 and IL-6 in scar tissues of HPS mice after treatment with suramin at low and high doses were significantly reduced (P<0.01). The results of ELISA showed that the levels of TNF-α, IL-6, IL-10 and TGF-β1 in the scar tissues of HPS mice after treatment with suramin at low and high doses were significantly reduced (P<0.01). CONCLUSION: Suramin inhibits the formation of HPS, which may be related to the inhibition of fibroplasia and reduction of local inflammatory response.     

一氧化碳(CO)在植物体内的生理生化作用研究进展

为了促进一氧化碳(CO)在植物生理生化方面的研究,本文归纳了CO在植物体中的生物合成途径,CO作为信号分子对植物各种生理功能的调控,以及CO与其他信号分子之间的相互作用。经过分析得出,CO在植物生物胁迫过程中的作用及其作用机制方面的研究还很少,因此,CO在这方面的研究将会成为今后的研究重点。     

水分胁迫对花生不同器官非结构性碳水化合物含量的影响

为探讨不同生育时期水分胁迫对花生不同器官非结构性碳水化合物(NSC)“库—源—流”间的变化动态,以‘花育20号’和‘花育27号’花生品种为试材,采用控制条件下的防雨棚池栽方法,研究了花生生长发育过程中不同生育时期水分胁迫下,非结构性碳水化合物(NSC)在花生叶片、茎、根和荚果等器官中的动态变化。结果表明,全生育期干旱胁迫使花生叶片、茎和根中可溶性总糖含量和淀粉均明显升高,但荚果中可溶性糖含量却明显降低。无论何生育时期受到干旱胁迫均使得叶片中可溶性糖含量峰值提前15天左右出现,“源”物质输出提前但输出量降低,叶片提前衰老。生育前期干旱胁迫使滞留在荚果中的NSC含量增加,结荚期后干旱胁迫反而利于荚果中NSC的转化。全生育期水分适宜处理叶片中NSC含量相对较低且变化较小。由此表明,干旱胁迫降低了NSC由源至库的运输和转化,使荚果“库”容量降低。