Phase transition behavior of elastin-like polypeptides oligomerized with the Foldon domain北大核心CSCD

To investigate the underlying mechanism of the unique phase transition behavior of SpyCatcher-ELPs40 (C-E) and the influence of the oligomerization domain on the phase transition of C-E, we constructed a non-covalent three-armed star oligomerization of C-E-F and E-F by fusing the Foldon (F) domain with SpyCatcher-ELPs40 (C-E) and ELPs40 (E). Results showed that the phase transition temperature of ELPs40 fused with Foldon was higher than that of ELPs120, whereas it was lower than those of ELPs40 and the SpyTag/SpyCatcher-mediated covalent three-armed elastin-like polypeptides (ELPs). This proved that the topology of ELPs could affect their phase transition behaviors. The phase transition temperature of C-E-F was 28.8 ℃ and 35.6 ℃ higher than those of C-E and ELPs40, respectively, although C-E-F had a similar sequence with C-E and ELPs40. When the concentration of NaCl was 0.8 mol/L, the differences in the phase transition temperatures were 41.2 ℃ and 47.1, respectively. We could only observe the phase transition of C-E-F in the Na2CO3 solution with high concentration (≥ 0.7 mol/ L); however, the phase transition could be clearly detected in the Na2SO4 solution, even when the concentration of Na2SO4 was very low. This result was obviously inconsistent with the Hofmeister series. This is the first report of non-linear ELPs that has shown this unique phase transition behavior. The possible reason was related to the charges distributed on the solvent accessible surface and the oligomeric state of C-E-F triggered by the Foldon domain. © 2018 Science Press. All rights reserved.     

昆山城市化与生态系统服务的关系定量研究

在通过对昆山市1990~2006年城市化水平和生态系统服务价值变化评价的基础上,分析区域城市化与生态系统服务之间的耦合关系。结果表明:昆山的城市化相对水平在研究年份内不断提高,从1990年的0.18上升到2004年的0.60;用价值量表征的生态系统服务水平在研究年份的变化呈先下降后上升的趋势;区域的生态系统服务相对水平与城市化相对水平之间的关系呈不规则的"U"型特征,二者的关系可以用方程式y=-2.5873x4+5.2542x3+0.4227x+0.98(R2=0.89)较好的表征。     

An investigation of the relationship between raw coal characteristics and effluent quality of Kedla and Rajrappa Washeries, Jharkhand, India

An attempt was made to investigate the relationship between raw coal characteristics and effluent quality in two coking coal washeries of Central Coalfields Limited, Kedla and Rajrappa in Jharkhand State, India. Coal samples-raw coal feed, washed fine clean coal, washed coarse clean coal, middlings and rejects were collected. Similarly, raw water (intake to washery) and effluent samples generated in the washeries, namely, fine coal jig under water, coarse coal jig under water and slurry pond water were also collected over a period of 6 months. Parameters outlined in Ministry of Environment and Forest (MoEF) Schedule VI Indian standards were determined, both in coal samples and water/washery effluent samples. Apart from the parameters listed in the standard, sodium, potassium, calcium, magnesium, sulphate and chloride found to be present in coal were also determined in coal and water samples. The processing results essentially in production of huge quantities of suspended material, which is beyond the stipulated limit of 100mg/l as specified in the Standard. Lowering of pH was observed in both the washeries. The trace/heavy elements were found to be concentrated in the heavier fractions in rejects produced from the washery. The concentrations of major elements in coal-Na, K, Ca, Mg, and minor elements in coal-Mn; F, SO4 and Cl were found to be higher in process water than in raw water indicating that these elements are transferred from coal to the water in washeries. However, only in the case of Mn, the stipulated limit of the effluent standard was exceeded. Trace elements like As, Se, Hg, Cd, though found to be present in coal, were absent in the process water indicating that these elements are not released by coal during washing.     

庆阳市环境-经济耦合系统动态演变趋势分析:基于能值理论与计量经济分析模型

分析了1978～2007年庆阳市环境-经济系统的能值流量与能值效率的演变轨迹.并以环境负荷率(ELR)、能值废弃率(EWR)作为环境压力指标,运用协整检验、Granger因果检验和向量误差修正模型(VECM),通过分析人均GDP与环境压力指标变量之间在时序维度上的因果关系和相互影响程度,进一步阐述经济与环境系统的耦合关系及其动态特征.结果表明,庆阳市经济发展对不可更新资源的依赖度大,环境-经济系统的产出效率总体下降,但环境负荷不断上升.计量分析表明,经济增长与环境压力之间存在单向因果关系,且已形成"恶性循环圈",环境-经济耦合系统表现出不可持续的发展态势.     

新疆地理环境与地方性甲状腺肿关系剖析

用防治干预前全疆病区收集的资料分析地方性甲状腺肿与地理环境关系．从中生代到第三纪中期，塔里木西南部发生多次海侵海退．晚第三纪喜马拉雅运动导致昆仑山脉、天山山脉和阿尔泰山上升形成三山夹两盆地的地貌．居民甲状腺肿患病率自北向南而加重，各区降水量与病情关系不明显．河流中段病情随着河流径流量增加而上升．近河床区患病率高于远离河床者．盆地倾斜平原患病率由上向下逐渐减轻．第三纪海侵区患病率远高于其它地区．海侵区远端和中段的患病率高于近端区．新疆地方性甲状腺肿分布与地理因素有明显关系．     

论库区贫困与库区发展：以山东大中型水库区为例

水库区是水库水面与周边陆地的区域复合体。本文以山东大中型水库区为例，在调查研究的基础上，探讨了库区贫困的根源及库区脱贫的出路，并提出了库区发展的战略构想。     

RAPD分子标记在鉴定香樟优选株和普通株中的应用

从85个随机引物中选10个随机引物对8个香樟样品的DNA进行了扩增，应用RAPD技术区别6个优选株和2个普通株，共获得78个DNA片断，把这些DNA片断作为遗传位点用UPCMA法计算出各材料间的遗传相似性系数，并作了聚类分析．在D＝0．738处8个样品分为两大类，而且普通株同优选株的亲缘关系很近．图2表2参9     

应用理论线性溶解能关系预测部分卤代芳烃的正辛醇／空气分配系数

以线笥溶解能关系（ＬＳＥＲ）理论为基础推导出一种理论线性溶解能关系（ＴＬＳＥＲ）模型。采用量子化学ＰＭ３算法，计算了部分卤代芳烃的分子平均极化率（α）等参数，并成功地应用于部分卤代芳烃正辛醇／空气分配系数（Ｋｏａ）的拟合与预测。研究表明，极化率是影响这些卤代芳烃的Ｋｏａ值的唯一参数，Ｋｏａ值随着极化的增大而增大。     

TSP与PM10相关性及其应用探讨

对环境空气中TSP(滤膜重量法)和PM10(压电晶体仪器法)进行同步监测，通过19组的测定结果表明，两者之间存在相关关系，经一元线性吲归，得回归方程：Y=0．1591 2．3213x。并经相关系数显著性水平检验，表明在99．9％的置信水平下TSP和PM10线性相关非常显著。     

环境空气中TSP与PM10相关性及其应用

对环境空气中TSP和PM10进行同步监测，通过30组的测定结果表明，两者之间存在十分密切的相关关系，经一元线性回归分析，得回归方程：y=0．0349＋1．2819x。并经相关系数显著性水平检验，表明在99．9％的置信水平下TSP和PM10线性相关非常显著。