Cloning and characterization of a glucose 6-phosphate/phosphate translocator from Oryza sativa

Plastids of nongreen tissues import carbon as a source of biosynthetic pathways and energy, and glucose 6-phosphate is the preferred hexose phosphate taken up by nongreen plastids. A cDNA clone encoding glucose 6-phosphate/phosphate translocator (GPT) was isolated from a cDNA library of immature seeds of rice and named as OsGPT. The cDNA has one uninterrupted open reading frame encoding a 42 kDa polypeptide possessing transit peptide consisting of 70 amino acid residues. The OsGPT gene maps on chromosome 8 of rice and is linked to the quantitative trait locus for 1000-grain weight. The expression of OsGPT is mainly restricted to heterotrophic tissues. These results suggest that glucose 6-phosphate imported via GPT can be used for starch biosynthesis in rice nongreen plastids.     

水溶性膨胀型防火涂料的研制

在实验研究基础上,提出以廉价的脲醛树脂为基料,辅以相关助剂制取膨胀型防火涂料的新方法。与传统防火涂料相比较,该涂料价格低廉,同时具有良好的透明性,具有较好的市场前景。     

淀粉磷酸单酯的合成及取代度的测定

本就淀粉磷酸单酯的反应时间,反应温度,磷酸盐加入量三个因素对产品取代度（D,S)的影响进行了探讨,从而确定出较佳的工艺条件为：反应温度150℃,反应时间25min,磷酸盐加入量度16％。     

纳米空心羟基磷酸锌的制备及表征

以六水合硝酸锌(Zn(NO3)2·6H2O)及磷酸氢二铵((NH4)2HPO4)为反应原料,三羟甲基乙烷(TME)为反应助剂,采用化学沉淀法以非模板的方式制备了具有空心结构的纳米羟基磷酸锌粉体。反应温度控制在20°C以下,使用氨水调控反应体系的pH值约8.5。利用X射线衍射、傅里叶变换红外吸收光谱、扫描电子显微镜、透射电子显微镜、热重分析仪及电感耦合等离子光谱发生仪对反应产物的晶体结构、形貌及元素含量进行了表征。结果表明,最终得到的产物具有空心结构,壁厚约7 nm,粒径30～50 nm。产物具有特殊的晶体结构特征,其可能的化学式为Zn5(PO4)3(OH)x·(2-x)H2O。通过简单的化学合成得到了一种新型无机纳米空心材料。     

Right–left digit ratio (2D:4D) predicts free testosterone levels associated with a physical challenge

Abstract

There is evidence that the digit ratio (2D:4D) is a negative correlate of prenatal levels of testosterone, but there is no association between 2D:4D and the circulating levels of both total and free testosterone. Sports provide a physical challenge and participants often show increased levels of free testosterone immediately preceding and during competition. We tested this hypothesis of a link between 2D:4D and testosterone under challenge in 79 professional rugby players using the following procedures; (i) 25 players were physically challenged using a repeated sprint agility test, and saliva samples were assayed for testosterone immediately preceding the repeated sprint agility test (time 1) and 5 minutes (time 2) and 20 minutes after completion of the repeated sprint ability (time 3); (ii) 54 players were also tested for salivary testosterone in an unchallenged condition. We found that right-left 2D:4D was significantly and negatively related to testosterone concentrations at times 1, 2 and 3 following the repeated sprint agility test (P < 0.05) and there was no association between the 2D:4D and basal testosterone levels in the unchallenged group. We suggest that low right–left 2D:4D is a predictive marker of free testosterone responsiveness when trained men are physically challenged, and that this association is programmed by the action of prenatal testosterone.     

中和料浆浓缩法制磷铵工艺

主要介绍中和料浆浓缩法制磷铵工艺原理,技术发展现状,并进行了展望。     

珠江广州河段中磷的形态研究

本文通过形态分析的方法,系统地研究了磷在珠江广州河段中悬浮物、溶液及底泥中的存在形态及分布规律,探讨了影响磷存在的因素,得出了钡是影响底泥中磷浓度的主要因子;水温,pH值及NH_3—N的存在影响水中正磷酸盐浓度等结论。     

饲料级磷酸氢钙生产工艺方法综述

本文综述介绍目前国内外饲料级磷酸氢钙的生产工艺方法和正在开发推广使用的新生产工艺方法。     

补充肌酸对运动能力和健康的影响

就肌酸在能量代谢中的作用、补充肌酸对肌肉中肌酸含量的影响和对运动能力的影响等方面进行了文献综述与分析。     

尼尔通对足球运动员最大有氧能力的影响

PALIER测试能够较好评定足球运动员的最大有氧能力。尼尔通作为外源性磷酸肌酸能有效提高最大有氧能力，其作用机理是通过供给心肌及骨骼肌细胞代谢所需要的能量和促进膜稳定作用及改善组织微循环等功效来实现的。