建筑路径网络的拓扑学分析

通过拓扑学的网络分析方法,从建筑路径的整体性特征人手,建立了以结点、弧段为基本构成要素的拓扑路径网络。提出了路径网络的平面嵌入定理,立体状网络转换方法,以及立体网络的判断问题。并分别对路网的结构、路径的可靠性、可达性、可贯穿性进行阐述。力求利用拓扑学原理解决一些建筑路径的设计中所遇到的问题,从而为路径设计和真实地构建路径奠定了基础。     

Housing location choices of the poor: does access to jobs matter?

Abstract

This research investigates whether access to jobs affects poor households’ residential location choices using data from individual households in the Chicago Metropolitan Area. Our results, based on discrete choice models, show that the effects of job accessibility on household location choices are contingent upon households’ automobile ownership and employment status. Places with higher job accessibility by public transit mode are more likely to attract poor households that do not own cars but have at least one employed worker or one labour force participant, while job accessibility by automobile travel mode has no positive effect on the location choices of poor households who own automobiles. The results stress the importance of job accessibility for those poor households with limited transportation mobility but strong needs for access to jobs.     

Job accessibility impacts of intensive and multiple land-use scenarios for the Netherlands’ Randstad Area

This paper examines job accessibility impacts of intensive and multiple land-use scenarios in the Netherlands’ Randstad Area for the period 1996–2030. The scenarios involve a heavy increase in the density and diversity of activities around railway stations. Accessibility impacts are examined using location-based accessibility measures and utility-based accessibility benefit measures within a high-resolution land-use/transport interaction modelling framework, taking into account the regional demand for economic activities and possible market responses. It is concluded that extreme concentrations of economic activities at central urban locations well served by public transport are not to be preferred over less heavy concentrations of economic activities at more locations. Heavy concentrations of new firms may firstly repel existing firms in the neighbourhood and secondly result in decreasing marginal returns of accessibility benefits for public transport users.     

The effects of an implemental mind-set on attitude strength.

The authors investigated whether an implemental mind-set fosters stronger attitudes. Participants who made a decision about how to act (vs. those who held off) expressed a more extreme attitude toward an issue unrelated to the decision (Experiment 1). Participants who planned the implementation of a decision (vs. deliberated vs. control) exhibited less ambivalent (Experiment 2) and more accessible (Experiment 3) attitudes toward various objects unrelated to the decision. Moreover, an attitude reported by planning participants better predicted self-reported behavior 1 week later (Experiment 4). Finally, results suggest that the effect of an implemental mind-set on attitude strength toward unrelated objects is driven by a focus on information that supports an already-made decision (Experiment 5). Implications for attitudes, goals, and mind-sets are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

液氨预处理对纤维素可及度和反应性的影响

棉短绒纤维素在25℃和1．03MPa压力下分别用液氮预处理120min和180min,纤维素的可及度和反应性大为提高,与未经处理的棉短绒比较．120min和180min液氨处理样的水吸附保持值（VWR）分别提高41％和60％,碘吸附值（VIS）分别提高90％和131％。液氮处理纤维素的羧甲基化反应速率也有较大提高.CMC水溶液的透明度和H-NMR谱的分析表明,取代基沿分子链分布的均一性和失水葡萄糖单元上三个羟基分布的均一性都有明显的提高。     

公平性视角下太原市区城市公园服务水平研究

城市公园服务的公平性关乎到居民的社会公平和生活质量,尤其是社会阶层分化和贫富差距的不断扩大,居民日益追求更高品质的绿色开放空间,因此合理的公园布局对绿色空间规划建设至关重要.选取太原市区城市公园为研究对象,基于社会空间结构的分异对比分析各乡镇街道公园服务能力的差异性,继而选取具有代表性的低学历人群、老年人和儿童作为目标...     

景观可达性作为衡量城市绿地系统功能指标的评价方法与案例

由于城市绿地指标（包括绿地率和人均绿地指标）受城市边界的主观性和可变性以及城市中绿地的空间分布的影响而有很大差异,这些指标很难或不足以衡量城市绿化和环境质量。为此,笔者提出以景观可达性作为评价城市绿地系统对市民的服务功能的一个指标。以中山为例,这一指标不但可以完善绿地（或其它服务设施）实际效用的评价体系,同时,为实现以人为本的城市规划思想提供了一个有力的依据。     

Origin of Increased Solvent Accessibility of Peptide Bonds in Mutual Synergetic Folding Proteins

Mutual Synergetic Folding (MSF) proteins belong to a recently discovered class of proteins. These proteins are disordered in their monomeric but ordered in their oligomeric forms. Their amino acid composition is more similar to globular proteins than to disordered ones. Our preceding work shed light on important structural aspects of the structural organization of these proteins, but the background of this behavior is still unknown. We suggest that solvent accessibility is an important factor, especially solvent accessibility of the peptide bonds can be accounted for this phenomenon. The side chains of the amino acids which form a peptide bond have a high local contribution to the shielding of the peptide bond from the solvent. During the oligomerization step, other non-local residues contribute to the shielding. We investigated these local and non-local effects of shielding based on Shannon information entropy calculations. We found that MSF and globular homodimeric proteins have different local contributions resulting from different amino acid pair frequencies. Their non-local distribution is also different because of distinctive inter-subunit contacts.     

An optimized FAIRE procedure for low cell numbers in yeast

We report an optimized low‐input FAIRE‐seq (Formaldehyde‐Assisted Isolation of Regulatory Elements‐sequencing) procedure to assay chromatin accessibility from limited amounts of yeast cells. We demonstrate that the method performs well on as little as 4 mg of cells scraped directly from a few colonies. Sensitivity, specificity and reproducibility of the scaled‐down method are comparable with those of regular, higher input amounts, and allow the use of 100‐fold fewer cells than existing procedures. The method enables epigenetic analysis of chromatin structure without the need for cell multiplication of exponentially growing cells in liquid culture, thus opening the possibility of studying colony cell subpopulations, or those that can be isolated directly from environmental samples.     

微波协同氧化钙处理对植物纤维失水率与可及度的影响研究

采用氧化钙高速捏合处理,再辅以微波辐射协同处理桐壳纤维和水葫芦纤维,以期使它们适用于制备木塑复合材料。通过失水率、保水值和红外光谱测试,研究了处理条件对这两种植物纤维的失水率和可及度的影响,重点讨论了保水值、分子间氢键百分含量和红外结晶指数等可及度参数的变化规律,并简要探讨了植物纤维的脱水机理。结果表明:微波协同氧化钙处理可延缓植物纤维的失水性和降低植物纤维的失水率,归因于经处理后植物纤维的可及度被提高。