社会权利交换视角下的农民工组织维权

论述了社会权利交换理论下劳资关系失衡的原因及表现;运用经济学理论,对农民工组织自发维权的公共产品属性与农民工通过组织维权的诉求之间的关系进行了分析;最后,基于企业内工会的低效性,提出了几种外部工会的构建方案。     

偶氮二异丁脒盐酸盐引发甲基丙烯酰胺接枝真丝纤维的反应性及工艺条件研究

对真丝织物接枝增重是改善其抗皱性和耐水洗性能的方法之一。采用偶氮二异丁脒盐酸盐(AIBA)为引发剂,将单体甲基丙烯酰胺(MAA)接枝到真丝纤维上,研究接枝的反应性及工艺因素对真丝织物接枝增重率的影响。通过单因素试验获得引发剂AIBA引发单体MAA接枝真丝纤维的最佳工艺条件是:MAA浓度0.31 mol/L,AIBA浓度2.95 mmol/L,浴比1∶30,反应液pH 9,反应温度80℃,反应时间60 min。当单体MAA和引发剂AIBA的浓度分别为0.31 mol/L、2.95 mmol/L时,真丝纤维的活性基团与单体、引发剂之间的反应性(表观反应速率)Rg=K[MAA]1.58[AIBA]0.21,由此得出单体MAA在水相中接枝真丝纤维的表观活化能为148.46 kJ/mol。     

Genetic estimates of population structure and dispersal in a benthic stream fish

Abstract–  Comparing genetic and demographic estimates of dispersal in freshwater fish can improve understanding of movement distributions and population connectivity. Here we examined genetic variation among mottled sculpin (Cottus bairdi) in the Nantahala River (North Carolina, USA) to compare genetic estimates of dispersal with estimates derived from mark–recapture studies of individual movement. Microsatellite‐based analysis of gene flow revealed evidence of strong isolation by distance among locations spanning only 5.6 km and limited dispersal among clusters of sites separated by swift cascades. Estimates of between‐cluster contemporary dispersal rates derived from Bayesian assignment tests ranged from 1% to 6%, with most movement occurring among adjacent clusters in a downstream direction. Evidence of a long‐term net immigration asymmetry and decreasing genetic diversity from downstream to upstream locations indicates that historical patterns of stream colonisation contrast with contemporary dispersal patterns. Our findings are largely consistent with predictions from individual movement patterns but suggest that long moves (>500 m) are more frequent, and maximum dispersal distances are greater than what has been reported from mark–recapture studies. The discrepancy may reflect spatial limitations of mark–recapture methods or temporal variation in dispersal in individuals and populations.     

Selection and characterization of ssDNA aptamers specifically recognizing pathogenic Vibrio alginolyticus

Vibrio alginolyticus (V. alginolyticus) is a major opportunistic pathogen to both marine animals and humans, which has also caused heavy economic losses to mariculture. The aim of this study was to develop highly specific aptamers for V. alginolyticus. Single‐stranded DNA (ssDNA) aptamers with high binding affinity to viable V. alginolyticus were generated by Systematic Evolution of Ligands by Exponential Enrichment (SELEX) and identified by flow cytometric analysis in this study. The selected aptamers showed high specificity for V. alginolyticus and low apparent binding for other bacteria. The aptamers formed distinct stem‐loop structures, which could form the basis of aptamers’ specific binding to the target V. alginolyticus. Aptamer VA2 and VA8 showed particularly high binding affinity constant (Kd) of 14.31 ± 4.26 and 90.00 ± 13.51 nM, respectively. The aptamers produced no cytotoxic effects in vitro and in vivo. ssDNA aptamers were successfully selected against the viable bacteria pathogen V. alginolyticus by SELEX. The aptamers selected in this study could be not only applied as specific chemical molecular probes for studying V. alginolyticus pathogenesis to Trachinotus ovatus, but also developing rapid convenient diagnosis assay for V. alginolyticus infection, even when applied to the complex sample matrix, such as food and environment samples.     

水稻磷素对开放式空气CO2浓度增高响应的研究

2001～2003年利用农田开放式空气CO2浓度增高(FACE)系统平台，研究FACE对武香粳11号不同生育时期磷素含量、吸收、分配及其效率的影响。结果表明：①FACE处理使水稻不同生育时期植株磷素含量增加，增幅为2．48％～18．84％；②FACE处理使水稻不同生育时期磷素积累量显著或极显著增加，增幅为28．74％～59．11％，生育前期的增幅明显大于生育中、后期；⑧FACE处理对水稻抽穗前磷素在叶片、茎鞘中的分配比例无显著影响，但使抽穗后磷素在稻穗中的分配比例明显减少，在叶片和茎鞘中的分配比例明显增加；④FACE处理使水稻不同生育时期磷素物质生产效率增加，增幅为2．53％～16．58％；⑤FACE处理使水稻磷素籽粒生产效率和收获指数下降，降幅分别为6．53％～15．51％和1．48％～9．04％。     

葡萄在散放条件下低浓度臭氧保鲜效果的研究

通过对散放条件下的葡萄进行低深度的臭氧保鲜实验，以期发现1种安全、无污染、低耗高效、易操作的新的葡萄保鲜方法。     

从苦豆子种子中提取生物碱的方法研究

对苦豆子种子中生物碱进行了提取、分离及苦参碱的定性和定量分析的研究。将苦豆子粉碎后,在室温下分别用0.4%盐酸、95%乙醇、1%氨水氯仿、无水乙醇溶剂冷浸7天共4次,经脱脂、酸化、碱化、萃取,得到生物碱;通过薄层层析(TLC)法进行单碱的分离,气相色谱(GC)法进行苦参碱的定性和定量分析。结果表明:以上4种提取方法出碱率分别为3.67%、2.73%、2.47%和1.60%;薄层层析(TLC)检查,以上4种方法提取的苦豆子生物碱中至少含有四种单一生物碱;气相色谱检测证明了以上4种方法提取的苦豆子生物碱中均含有苦参碱,其百分含量分别为8.460%、7.553%、5.675%、0.893%。其中0.4%盐酸冷浸提取法提取率明显高于其他溶剂提取率,为苦豆子生物碱优选提取方法。