依托示范基地建设 提升农机科技应用水平

重点介绍在新疆粮食、棉花、特色林果业和畜牧业四大基地建设中,农机化新技术、新机具引进推广运用过程中带来农牧民增收的巨大成就,提出围绕四大基地建设进一步做好农机推广项目的具体措施及对策。     

PRSV NIa-pro、NIa-vpg、NIb酵母双杂交诱饵表达载体的构建及自激活检测

用PCR技术获得NIa-pro、NIa-vpg、NIb基因片段,将这些基因分别克隆到pBD-GAL4载体中,构建酵母双杂交系统的诱饵载体pBD-GAL4-NIa-pro、pBD-GAL4-NIa-vpg和pBD-GAL4-NIb.测序正确后,将重组质粒导入YRG-2酵母菌株,检测其表达产物对酵母细胞有无毒性及对报告基因有无激活作用.结果表明,获得了正确的NIa-pro、NIa-vpg、NIb基因片段,并成功克隆到pBD-GAL4诱饵载体中,且转化有诱饵载体的YRG-2在SD/-Trp营养缺陷平板上生长良好,说明表达产物对酵母细胞无毒性,对报告基因也无自激活作用,为下一步利用酵母双杂交系统检测与NIa-pro、NIa-vpg、NIb蛋白相互作用的蛋白奠定基础.     

Evaluation of Joint Toxicity of Enrofloxacin and Three Antimicrobials on MRC-5 Cells

The aim of this study was to evaluate the combined toxicity of enrofloxacin with each of three antimicrobials (ciprofloxacin,florfenicol and sulfamethazine).MRC-5 cells were used as a cell model to simulate the damage of lung cells caused by mixed contamination of antimicrobials.Multiple concentration gradients and mixing ratios were set.CCK-8 method was used to determine the inhibition rate of cell growth caused by four antimicrobials and the inhibition rate of cell growth caused by enofloxacin mixed with three antimicrobials,respectively.Then Chou-Talalay method was used to fit the median effect plot and to calculate the combination index (CI) value.The results showed that the growth inhibition rates of MCR-5 cells caused by four single drugs went up in a step-like manner with the increase of drug concentration in the tested concentration range,among them,the growth inhibitory rate of MCR-5 cells by florfenicol was low (<4.5%).The combined toxicity of the three binary combinations showed a concentration-dependent and mixing-ratio dependence.Mixing enrofloxacin and ciprofloxacin showed synergistic toxicity (CI<1) on MRC-5 cells at high and middle concentration groups,and antagonistic toxicity (CI>1) at the very-low-concentration groups.Mixing ciprofloxacin and florfenicol mainly showed an inhibited toxicity (CI>1).Binary combination enrofloxacin and sulfamethazine might present either a synergistic joint toxicity (CI<1) or an antagonistic joint toxicity (CI>1) as the concentration and mixing ratio changing.This study showed that it was necessary to assess the combined toxicity of antimicrobials in the toxicity evaluation of antimicrobials.Using Chou-Talalay method,the joint toxicity of multiple antimicrobials could be quickly and efficiently determined at cellular level.     

期刊回溯建库工作中常见问题及对策

本文就利用汇文系统进行期刊回溯建库实践中常见的问题进行了分析，并提出了相应的对策。     

"双一流"建设背景下西北农林科技大学草坪学双语教学改革模式探索

国家"双一流"建设要求全面提升大学生的综合素质和国际视野.草坪学作为草业科学专业重要的专业课程,实施双语教学是教学改革的必然趋势.本文针对西北农林科技大学草坪学双语课程传统教学中存在的问题,基于学校优慕课网络教学平台,探讨了践行翻转课堂教学模式在草坪学双语教学中的实施方法.在本课程改革中设置"课前–课上–课后"3个教学环节,教师能够通过线上和线下混合式教学,公正、客观、实时、全面地了解学生学习过程中的学业完成情况,实现以教为主向以学为主转变,激发学生学习兴趣,促进学生混合式自主学习,培养学生创新能力,提升教学效果和人才培养质量.     

桥梁高墩施工平台无支架提升技术应用

惠河高速公路东江特大桥主桥采用空心矩形墩，最高桥墩达28m，本文介绍高墩无支架提升模板及施工平台的施工技术。     

粘钢加固技术的设计与应用

粘钢即在被加固构件表面粘贴钢板，籍以提高其承载能力，目前粘钢技术已在实际工程中得到广泛应用，技术日趋成熟，粘钢有施工简便、工期短、占用的空间小等优点；本文根据施工经验提出施工方法，以利在实际加固当中取得较好的经济效益。     

The scope for reconciling public good and private forestry in the United Kingdom

The nature of private forestry in the UK as an economic activity is changing, with increasing ‘public good’ demands being placed on forest owners, with or without compensation from government. Although the motives for owning woodland are weakly researched, it is evident that amenity and recreational interests rather than formal productive economic activity are a major force in influencing woodland purchase and may well be a dominant force in woodland management over many parts of the UK. Recent research suggests a need for recognition of the high value of the public goods and, in particular, recognition of their high levels of spatial variability, whilst recognising that the public good — private good dualism is an oversimplification of the actual situation. New policy instruments are currently being implemented in various parts of the UK by devolved governments, and their capacity to both remediate market failure and address the needs of forest owners is considered. Their voluntary character and the preferences of forest owners may seriously constrain the optimal delivery of public goods. Further, existing policy instruments may be seen as insufficiently geographically targeted to areas where the greatest social benefits could be anticipated from policy-induced improvements in public good values.     

高等级公路沥青混凝土路面施工的几点体会

结合双鸭山双七二级公路改建工程第3合同段对沥青混凝土路面的施工过程，介绍了高等级公路沥青混凝土路面的配合比设计和施工方法，对今后的沥青混凝土路面施工有较好的借鉴作用。     

厦门市同安区林业生态建设与农村经济发展浅析

通过对林业生态建设的必要性、在实施过程中采取的措施和农村经济发展状况等方面的探讨,阐述了沿海地区林业生态建设与农村经济发展的关系,提出了社会经济可持续发展的途径。