几株光合细菌的表型特征及DNA－NDA同源性分析

对５株新分离的光合细菌从形态、生理生化及ＤＮＡ－ＤＮＡ同源性等方面进行了研究．结果表明，菌株８与深红红螺菌（Ｐｈｏｄｏｓｐｉｒｉｌｌｕｍｒｕｂｒｕｍ）的模式菌株ＡＴＣＣ１１１７０的ＤＮＡ－ＤＮＡ同源性为９７％，菌株３７与沼泽红假单胞菌（Ｒｈｏｄｏｐｓｅｕｄｏｍｏｎａｓｐａｌｕｓｔｒｉｓ）的模式菌株ＡＴＣＣ１７００１的ＤＮＡ－ＤＮＡ同源性为８０％；菌株５５与球形红杆菌（Ｒｈｏｄｏｂａｃｔｅｒｓｐｈａｅｒｏｉｄｅｓ）的模式菌株ＡＴＣＣ１７０２３的ＤＮＡ－ＤＮＡ同源性为７１％；菌株４０和５２分别为另外两个ＤＮＡ同源群．根据各菌株形态、生理生化等表型特征以及ＤＮＡＧ＋Ｃｍｏｌ％和ＤＮＡ－ＤＮＡ同源性分析结果，确定了几株光合细菌的分类地位．     

我国城市地价评估模型及其空间分布规律研究

本文以城市地价产生地区差异的理论分析为依据,提出了城市地价的主要影响因素、因子,并以城市土地批租资料为基础运用逐步回归分析方法建立城市地价评估模型。根据模型估测了我国５１７个城市１９９２年的地价水平,最后分析了我国城市地价空间分布的规律及其未来走势展望。     

浙江省海岸带优势资源及其组合特点

浙江省海岸带以自然资源集聚、种类众多为其特色，它为振兴浙江经济提供了极为有利的条件。浙江海岸带有六项优势资源，即港口航道资源、水产资源、滩涂土地资源、海洋能资源、旅游资源以及岛屿资源。本文分析了这些优势资源的组合特点，并指出优势资源存在着多宜性、动态性，在开发利用过程中要加以综合规划，统一协调，目的是以期引起有关方面注意，采纳或参考。     

Clinical and pathological factors in spontaneous abortion following chorionic villus sampling

Twenty-nine cases of spontaneous abortion following first-trimester chorionic villus sampling (CVS) were reviewed out of a series of 722 patients. Of the 29 cases, there were only four abnormal CVS results. Pathological examination was performed in 79 per cent of cases, and this did not identify any characteristic pathological feature associated with spontaneous abortion after CVS. There was no obvious difference in the pathological features following the transabdominal (TA) or the transcervical (TC) methods. The majority of miscarriages occurred within 4 weeks of the procedure, but 38 per cent of cases aborted between 7 and 14 weeks after CVS. The TC method was used in 22 patients; the TA in 6; and both methods in 1 patient. The TA method was associated with a significantly lower fetal loss rate than the TC method (TA 2 per cent, TC 9 per cent, p < 0.001).     

Design and cognitive evaluation of 6 dynamic lane departure warning symbols

Objective: Lane departure, caused by inattention, distraction, drowsiness, or any unusual driver behavior, is a typical risk threatening the driver as well as other road users. Accurate perception of such situations through effective warnings would help drivers to avoid serious consequences. With regard to critical functions of warning symbols for risk communication, the present study focused on providing effective and easily perceivable symbols, compatible with human cognitive capabilities. Thus, the main purpose of the present study was to design and cognitively appraise 6 newly designed dynamic symbols, candidates for a new type of lane departure warning system.

Methods: Simplicity, familiarity, concreteness, meaningfulness, and semantic closeness were the major assessment criteria, defining cognitive features by the earlier researchers in the field. A total number of 187 driving license applicants, with a mean age of 20.58 years (SD = 3.20), participated in the present survey. The participants rated cognitive features of the 6 dynamic symbols along a 0–100 scale.

Results: Significant main effect of the element factor type of the designed symbols on rating cognitive features revealed that the existence of car element was the best predictor for illustrating lane departure. The interaction of both element factor and location of element factor significantly affected the ratings. However, the location of element factor did not solely have any strong effect on the ratings. The results also demonstrated that semantic closeness received the highest overall mean score across symbols (M = 61.80), especially within the symbols that include the car element (M = 75.67). Moreover, a significant difference was observed between the average ratings of the cognitive features, despite the fact that a significant correlation was found between cognitive features.

Conclusion: The most considerable result of the current study was the match between the symbol with the highest ratings and the International Organization for Standardization (ISO)-related icon in appearance. Because previous studies demonstrated a strong correlation between comprehension scores of the symbol and both semantic closeness and meaningfulness, high-level comprehensibility of the best ranked symbol is expected.     

废旧塑料处置地沉积物中邻苯二甲酸酯污染特征及其生态风险

为了解废旧塑料处置活动对区域水体的影响,采用气相质谱联用仪(GC-MS),对河北省某废旧塑料处置地沉积物中16种PAEs(phthalate esters,邻苯二甲酸酯)的污染特征和生态风险进行了研究. 结果表明:研究样地的w(∑₁₆PAEs)为0.527~102 μg/g, 平均值为18.9 μg/g,其中,DEHP〔邻苯二甲酸(2-乙基己基)酯〕是PAEs最主要的污染单体,平均占w(∑PAEs)的66.6%. 对该处置地的污染物源分析表明,沉积物中PAEs主要来源于废旧塑料回收利用过程中的环境排放. 沉积物中w(DEHP)(14.2 μg/g)和w(DBP)(1.41 μg/g)(DBP为邻苯二甲酸二正丁酯)均超过各自环境风险限值(ERLs),w(DIBP)(DIBP为邻苯二甲酸二异丁酯)超过了美国华盛顿州颁布的沉积物质量警戒限值(0.610 μg/g). 研究显示,沉积物中DBP对鱼类的生态风险及DEHP对藻类和鱼类的生态风险水平不可接受,应引起足够重视.      

Ergonomic Diagnosis of the Driver’s Workplace in an Electric Locomotive

This paper deals with research aimed at developing a method for ergonomic analysis of the driver’s workplace in an electric locomotive. It presents the structure of the diagnosis and its assumptions, and includes a re-evaluation of the questionnaire-expert method in ergonomic research. The article presents research data on weights and evaluations including their standard deviations for particular priority features. Ergonomic levels of the studied operator’s cabin in locomotives are compared.     

电袋复合除尘器的设计要点及工程应用

电袋复合除尘器是近年来发展起来的一种新的除尘技术,是在结合电除尘器和袋除尘器这两种传统的高效除尘技术的基础之上发展而来的。本文重点讨论了电袋复合除尘器设计过程中应重点关注的设计要点,并通过成功应用的改造工程实例,介绍了其改造过程和改造效果。     

赤壁市生态旅游资源特色与开发

赤壁生态旅游资源丰富,特色鲜明,类型齐全,具有较大的开发价值。通过对赤壁市开发条件、开发力和客源市场的分析,作者指出了该市开发旅游资源的巨大前景,提出了建立七种不同类型生态旅游区的构想。     

乌鲁木齐9、10号泉F~-映震特征的研究

从监测泉点的水文地质概况入手，结合近18年来的观测资料，分析并总结了9、 10号泉水中F-的映震特征： F-的地震前兆异常基本上都是正异常，且具有较好的重复性，即基本上遵循： 背景值-脉冲式突升-最高值-突降-恢复至背景值的规律。 而地震常常发生在F-含量恢复背景值后数天或数十天，仅有个别地震发生在F-含量达最高值时。 最后，初步认定了泉点较好的地震构造环境是造成该9、 10号泉F-具有映震灵敏性的原因。