油脂预乳化提高大豆拉丝蛋白素食香肠品质

为了提高大豆拉丝蛋白(Textured Fibril Soy Protein,TFSP)素食香肠的品质,该研究将油脂预乳化工艺应用于TFSP素食香肠的加工,利用响应面试验设计优化了预乳化工艺条件,采用质构分析仪测定分析了产品的质构特性,并进行了感官评价。结果表明优化后的最佳预乳化工艺条件为菜籽油含量445g/L、大豆分离蛋白浓度105g/L、乳化机剪切速率9.0×103r/min。与对照组相比,此条件下制作的预乳化-TFSP素食香肠的凝胶强度、硬度和咀嚼性分别提高了约1倍、10%和26%,且产品口感鲜嫩、富有汁液感,感官评价得分显著提高。采用激光共聚焦显微镜观察分析了不同工艺制作的TFSP素食香肠在煮制前后微观结构的变化,结果发现油脂预乳化工艺可大大提高乳化油脂的稳定性和在香肠凝胶基质中的均匀分布,从而使乳化油脂的‘填充作用’得以发挥,不仅增强了TFSP素食香肠的保水保油能力,降低了蒸煮损失率,而且对香肠的质构和感官特性产生了重要影响。因此油脂预乳化工艺是一种辅助提高素食香肠整体品质行之有效的方法。     

茄子的组织培养和植株再生体系研究

以2个茄子品种：红茄和紫长茄的子叶和下胚轴为外植体,探讨了不同生长调节物质对外植体分化的影响和不同品种、不同外植体的分化能力差异,并建立了茄子的高频率离体再生体系。结果表明：培养基MS＋2,4-D 1.0 mg/L＋6-BA 0.5 mg/L诱导愈伤组织效果最好;诱导不定芽方面,培养基MS＋4-PU 0.1 mg/L诱导效果最好;1/2MS培养基较MS培养基更适合植株生根。     

Effect of chitosan-based edible coatings applied by vacuum impregnation on quality preservation of fresh-cut carrot

Edible coatings based on high molecular weight chitosan, pure or combined with methylcellulose or oleic acid, were applied to fresh-cut carrots cv. Nantesa by simple immersion and by applying a vacuum pulse (5 kPa for 4 min). Water vapour resistance, colour, mechanical properties and respiration rates of non-coated and coated samples were determined. Coatings improved sample appearance, since they diminished the occurrence of the white blush during storage. When applied by simple immersion, they neither conferred significant barrier properties nor the preservation of the mechanical properties of fresh-cut carrot samples. In contrast, coating application with a vacuum pulse enhanced all the positive effects, since the resistance of water vapour transmission of the samples was significantly improved, and better preservation of the sample colour and mechanical response during cold storage was obtained. Differences in film composition did not significantly affect the coating behaviour, probably due to the variability induced by different factors when coatings were applied to the carrot surface.     

基于ANSYS的某自卸车车架有限元分析

为了辅助某自卸车车架的设计,对此车架进行了模型的简化与建立。依靠ANSYS对装配后的车架进行了全局与局部的网格划分;在此基础上对弯曲工况、扭转工况、制动工况以及过减速带工况这四种典型工况进行了车架应力与变形分析。通过对变形位移图与应力分布图的分析得出了车架容易出现失效的区域,从而为车架强度设计提供了依据。     

1-MCP controls ripening induced by impact injury on apricots by affecting SOD and POX activities

The influence of 1-MCP on the response of apricots to mechanical injury (impact) and the potential involvement of oxidative stress was investigated. Apricots (Prunus armeniaca L. cv. Marietta) picked at an early ripening (commercial harvest) stage (11–11.5 °Brix) were dropped from 30 cm onto a flat, hard surface to simulate an impact injury; fruit were treated with 500 nl 1⁻¹ 1-MCP for 20 h at 20 °C before or after the impact injury. Injured fruit showed a substantial rise in ethylene production after 4 days, while in fruit treated with 1-MCP, this increase started after 6 days, with a production rate lower than that of injured fruit. Increase in the respiration rate was delayed for 1-MCP-treated injured fruit in comparison with untreated injured ones. Tissue softening was reduced by 1-MCP treatment, showing less tissue deformability. Scanning EM analysis of injured tissue revealed healthier cells in 1-MCP treated apricots. 1-MCP-treated the increase of superoxide dismutase activity (SOD) due to mechanical injury in the first 4 days and this behaviour was related to ethylene production. Peroxidase activity (POX) increased in injured tissue immediately but then remained stable; 1-MCP, particularly when applied before the impact, increased POX activity. These results indicate that using 1-MCP can control ripening acceleration of apricots induced by mechanical injury. SOD, POX, and ethylene relationships are discussed.     

Color change of fresh-cut apples coated with whey protein concentrate-based edible coatings

The effect of antioxidant type and content alone or in combination with edible coatings for fresh-cut apples was studied. Edible composite coatings were prepared from whey protein concentrate (WPC) and beeswax (BW). Ascorbic acid (AA) at 0.5% and 1% content, cysteine (Cys) at 0.1%, 0.3% and 0.5% content, and 4-hexylresorcinol (4-hexyl) at 0.005% and 0.02% were incorporated in the formulations as antioxidants. Apple pieces were coated with the emulsion coatings and weight loss, color (CIE L*, a*, b*, and browning index (BI)) and sensory evaluation were measured during storage. Results showed that incorporation of the antioxidant to the coating reduced browning compared to the use of the antioxidant alone. 4-Hexyl was the least effective at reducing browning, even when incorporated into the WPC-based coating. Increasing AA and Cys content decreased browning of coated samples. The most effective treatments were WPC–BW-based coatings with 1% AA or 0.5% Cys. Apple pieces treated with 0.3% and 0.1% Cys aqueous solutions showed a pinkish-red appearance, whereas this effect was not shown when similar levels of Cys were incorporated into the WPC–BW-based coating. Coating application did not reduces weight loss in fresh-cut apples, probably due to the high relative humidity of the product. A sensory panel was able to discriminate between samples coated with WPC–Cys and samples dipped in Cys aqueous solution, but not between samples coated with WPC–AA and samples dipped in AA aqueous solution.     

试论设施农业发展的现状及对策

设施农业以高度集约的现代工厂化生产为特征,是高产、优质、高效农业的必然要求.发展设施农业,有利于推进我国农业现代化建设.通过介绍国内外设施栽培的现状,分析了设施栽培出现的问题,尤其是联系广东省有关实际,提出了今后设施农业发展的策略.     

广东高职院校图书馆书目信息服务探讨

首先简述书目及书目信息服务,分析广东省76所高职高专院校图书馆书目信息服务的现状,最后提出加强高职院校图书馆书目信息服务的对策。     

人类表皮生长因子受体2蛋白在宫颈癌组织中的表达及意义

目的观察宫颈癌组织中人类表皮生长因子受体2（HER-2/neu）蛋白表达及其在宫颈癌发生发展中的作用。方法应用免疫组织化学方法检测20例正常宫颈组织、30例宫颈上皮内瘤样病变（CINⅠ-Ⅲ）和50例宫颈癌组织中HER-2/neu蛋白表达。结果宫颈癌组织中HER-2/neu蛋白表达显著高于宫颈上皮内瘤样病变（P〈0.01）,正常宫颈组织未见阳性表达;宫颈癌组织中HER-2/neu蛋白表达与肿瘤浸润深度、淋巴结转移、临床分期密切相关（P〈0.05）。结论 HER-2/neu蛋白表达上调可能在宫颈癌发生发展中起重要作用。     

Down-regulation of miR-153-3p attenuates H2O2-induced H9C2 cell injury by promoting Nrf2 expression

AIM To study the effect of microRNA-153-3p (miR-153-3p) knock-down on oxidative injury of H9C2 cells induced by H₂O₂ and its specific mechanism. METHODS The oxidative stress injury of H9C2 cell model was induced by H₂O₂, and then the cell viability and the expression of miR-153-3p were detected by MTT assay and RT-qPCR, respectively. The effects of miR-153-3p knock-down on the H9C2 cell injury under oxidative stress were studied by RNA interference technology. The targets of miR-153-3p were identified by Western blot and dual-luciferase reporter assay. RESULTS MTT assay showed that the viability of H9C2 cells was decreased with the increase in H₂O₂ concentration (P<0.05). The results of RT-qPCR showed that the expression of miR-153-3p was increased with the increase in H₂O₂ concentration (P<0.05). Knock-down of miR-153-3p increased the viability of H9C2 cells under oxidative stress, decreased the cell apoptosis and the content of malondialdehyde (MDA), and increased the activity of superoxide dismutase (SOD). The expression of nuclear factor E2-related factor 2（Nrf2） and antioxidant response element（ARE） activity were increased with the increase in H₂O₂ concentration (P<0.01). TargetScan analysis and dual-luciferase reporter assay showed that Nrf2 was one of the potential target genes of miR-153-3p. The results of Western blot further showed that over-expression of miR-153-3p inhibited the expression of Nrf2 (P<0.01), while down-regulation of miR-153-3p increased the expression of Nrf2 (P<0.01). Dual interference with Nrf2 and miR-153-3p significantly reduced H9C2 cell viability， promoted the apoptosis, increased MDA content, and decreased SOD activity in the presence of H₂O₂ (P<0.01). CONCLUSION Inhibition of miR-153-3p expression attenuates the injury of H9C2 cells induced by H₂O₂ through up-regulating Nrf2/ARE signaling pathway.