不同空间尺度三维建筑景观变化

以沈阳市铁西区建筑物三维信息为基础数据,从建筑高度、密度、体积与体形、分布均匀度与空间拥挤度等方面构建了三维建筑景观评价指标,分别从区域、功能分区和梯度带3个角度分析了三维建筑景观的变化特征.结果表明:从1997年到2008年,铁西区建筑向垂直方向扩张,建筑空间分布越来越不均匀,空间拥挤度、建筑平均体积与容积率逐渐增大;居住区平均高度、平均体积、覆盖率、容积率、空间拥挤程度最小,建筑分布最均匀;商业区除建筑高度变异系数和平均体形系数最小外,其余指标值最大;工业区高度变异系数和平均体形系数最大,空间分布最不均匀;从梯度带上看,建筑使用类型的差异决定了三维建筑景观的变化特征.     

城市居住区三维景观变化规律与影响因素

基于1997年1∶10000航片以及2002、2005和2008年QuickBird数据,应用Barista软件以及GIS、RS技术,提取了沈阳市铁西区居住区建筑物的三维信息,采用道路密度、绿化率、建筑平均高度、高度标准差、建筑覆盖率、容积率、建筑体形系数以及人口密度和人均GDP等指标,分析了1997—2008年铁西居住区改造过程中三维景观的变化规律与影响因素.结果表明:1997—2008年,铁西居住区工业建筑面积比重降低,商业与其他公共类建筑面积比重增加,居住、教育与医疗建筑面积比重基本保持稳定;研究区建筑数量减少,建筑覆盖率及体形系数降低,容积率、平均高度、高度标准差及道路密度、绿化率升高;在居住区有限的空间内,人口与经济活动容纳能力提高的同时环境质量也有所提高,建筑高度变异程度增大,建筑能耗降低.人口密度、人均GDP与容积率、道路密度和绿化率呈正相关,与建筑覆盖率呈负相关.     

沈阳城市三维景观空间格局分异特征

城市三维景观的研究有助于景观生态学研究向三维的发展和指导城市科学规划。本文利用Quick Bird影像提取了沈阳建成区的建筑三维信息,采用5个景观指标(平均高度、景观高度标准差、容积率、建筑体形系数和建筑密度)及空间统计分析方法研究了沈阳市建筑景观空间格局分异特征。结果表明:沈阳建成区的建筑景观主要以平房和多层建筑为主,中高层以上建筑数量最多的是铁西区,其他各区均有分布。沈阳市建成区不同高度的建筑在空间上呈现聚集分布状态并且存在显著的空间正相关关系;同时,沈阳市建成区的各个行政区不同高度的建筑也在各自行政区呈现聚集分布状态。沈阳市建成区的建筑密度与容积率在空间分布上存在明显的差异,高密度、高容积率的区域面积比重相对较少,城市土地利用强度有一定的提升空间。     

铁西区建筑景观时空变化特征及影响因素

城市建筑景观的时空演变特征对城市改造与规划的合理调整有重要的指导作用。本文基于Barista软件、GIS、RS等技术,提取了建筑物的3D信息,并采用建筑占地面积比重、建筑平均高度、建筑密度、建筑形状指数与空间质心模型等指标,分析了沈阳市铁西区建筑景观的时空变化特征与影响因素。结果显示:从1997—2008年,居住与商业建筑占地面积比重增加,工业建筑占地面积比重下降,建筑形状越来越规则,建筑密度降低,建筑在垂直方向上扩展;3个时段内,建筑景观变化的质心先由居住区向工业区转移,再由城市中心向外围移动;经济发展、人口增长与建筑平均高度呈正相关,与建筑密度呈负相关。城市改造政策对城市建筑景观的变化有重要的影响。随着离道路距离的增加,建筑平均高度降低,建筑密度先增高后降低。     

基于Barista的城市建筑景观动态变化——以沈阳市铁西区为例

基于Barista软件从高分辨率影像提取建筑物3D信息,结合ArcGIS软件,应用转移贡献率、建筑密度、建筑平均高度及建筑面积比例分析了沈阳市铁西区改造过程中建筑景观的动态变化.结果表明： 随着城市改造的进行,空地、居住、工业建筑与道路4种优势景观类型是景观变化的主体,空地、居住、商业建筑和道路面积增加,工业建筑面积减少.建筑密度降低,平均高度升高.建筑景观的区域差异明显,工业区建筑密度高于居住区,建筑平均高度低于居住区.离城市中心距离越远,建筑密度越小,建筑平均高度越低.     

基于缓冲带的贵港市城市景观格局梯度分析

运用景观格局指数与城市建成区缓冲带划分相结合的方法,分析了广西贵港市近20a来城市建成区整体景观与主要城市景观类型（公共设施用地、工业用地、居住用地及农田）的圈层梯度变化特征.分析结果表明：贵港市城市建成区可以看作是居住用地与公共设施用地的镶嵌景观,但这种镶嵌景观随着城市化的发展,存在日趋不明显的特征;整个景观层面的指数20a来在31个梯度带内,表现出相似的变化趋势,斑块面积指数显示出贵港市城市建成区存在两个较为明显的商业金融中心;各梯度带内景观的平均面积增大,景观的形状日臻规则,景观多样性随景观类型及均匀度的增加显著上升.2004年主要城市景观类型在缓冲区中间各带能够很好的反映出格局的变化特征,其中工业用地和农田用地的斑块数和斑块密度随缓冲区梯度表现出较为一致的变化特征,而公共设施用地和居住用地的梯度变化趋势相似.各个梯度带中工业用地形状最为复杂,所占比重最低,平均斑块面积最大;公共设施和居住用地形状较为简单,在各带中所占比重较高,平均斑块面积较小;农田景观在各带中所占比例变化不大,近似连续分布,对城市生态环境的调节起到一定作用.     

1964-2015年海南省八门湾红树林湿地及其周边土地景观动态分析

以海南省文昌市八门港红树林湿地及其周边土地为研究对象,采用6期遥感影像为主要的数据来源,建立起研究区域内1964、1972、1988、2000、2009、2015年50年的景观数据库,利用土地转移矩阵和表征景观破碎化过程的景观指数系统阐述了八门湾红树林湿地及其周边土地的土地利用/覆被变化以及景观破碎化的过程,探讨八门湾红树林湿地及其周边土地土地利用/覆被变化与景观破碎化过程之间的相互关系。结果表明：（1）1964-2015年间,研究区域内建筑用地、养殖水面面积持续增长面积比重分别上升了7.72%、12.55%,耕地、林地、红树林面积所占比重分别下降了7.01%、9.16%、9.74%。（2）1964-2015年间,研究区域内斑块数量增加了685个,平均斑块面积缩减了39.12%,聚合度下降了3.5%,最大斑块面积缩减了28.38%,蔓延度下降了9.26%,斑块平均形状破碎化指数和面积加权平均形状破碎化指数分别上升了0.0148、0.0207,斑块密度从1964年的0.0653个/hm²上升到2015年的0.1073个/hm²。（3）八门湾红树林湿地及其周边土地的土地利用/覆被变化与景观破碎化过程的相关关系主要体现在养殖水面、建筑用地面积变化对研究区域景观破碎化指数的影响上。养殖水面、建筑用地面积变化对研究区域景观破碎化过程的影响主要体现在聚合度、斑块数量、蔓延度的作用上。其中,养殖水面面积变化对研究区域景观破碎化过程的影响主要体现在其对红树林面积的侵占,使得红树林面积占研究区域总面积的比例由15%下降到5.25%,红树林由大面积连续集中分布趋向于小面积孤立分散分布。建筑用地面积变化对研究区域景观破碎化过程的影响主要体现在城市的快速发展、交通设施大量的建设。50年来,八门湾红树林湿地各地类之间的转化主要表现为红树林面积转化成养殖水面,林地和耕地面积转化为建筑用地,由此可见,人类活动能力的增强以及影响范围的不断扩大是引发八门湾红树林湿地景观破碎化的主要原因。     

基于模拟景观的城市森林景观格局指数选取

基于现实的沈阳城市森林景观,模拟了4个景观格局梯度,并选取了1个与之相应的现实景观格局梯度,分析了28个景观格局指数在各梯度对景观破碎化和景观斑块形状复杂性的反映,从而筛选出描述这两种景观格局特征的适宜景观格局指数.结果表明：斑块密度（PD）和平均斑块面积（AREA_MN）在城市森林景观破碎化方面表现出较规律的变化趋势,斑块密度随破碎化程度的增加而增加,平均斑块面积随破碎化程度的增加而减小;面积加权平均周长面积比（PARA_AM）在描述景观斑块形状复杂性方面与景观格局梯度相吻合,且随斑块形状复杂性的增加而增加,能够较为准确地描述景观斑块形状的复杂性.     

沈阳市铁西老工业区更新过程中建筑景观变化

我国处于快速的城镇化和城市更新过程中,城市扩展的研究多集中于边界扩张,而城市内部改造导致的格局变化研究不足。在遥感与GIS技术平台的支持下,以沈阳市铁西区为例,应用BRISTA软件和高分遥感影像,解译每栋建筑的三维信息,从建筑景观指标、统计分析、建筑景观更新格局和建筑平均高度自相关等角度分析了老工业区在更新过程中的建筑景观变化特征。结果表明,从1997—2011年,铁西区的建筑以多层建筑为主,单层建筑和低层建筑数量上总体呈下降趋势,多层建筑、中高层建筑、高层建筑和超高层建筑总体呈上升趋势;建筑景观向垂直方向扩张,建筑容纳能力提高,建筑能耗降低;建筑景观的更新与区域交通、与城市中心的距离和土地利用类型相关。建筑平均高度的空间分布与土地利用类型和距城市中心的距离相关。了解此过程中老工业区建筑景观的变化规律可为老工业区的城市规划与建筑更新提供有益的参考。     

铁西区城市改造过程中建筑景观的演变规律

探索城市改造过程中景观的变化规律对城市景观变化的预测有重要的指导意义。以沈阳市铁西区1997、2002、2005、2008年建筑物三维信息为基础数据。按照建筑物使用性质将其分为居住、工业、商业、教育与医疗、其他建筑5类,按照建筑物的高度将其分为平房、低层、多层、中高层、高层和超高层6类。采用转移矩阵法分析了不同时段建筑类型的更替规律。并将探索性空间数据分析法应用于建筑改造空间分布特征的研究。结果显示:1997到2002年,居住建筑是建筑改造的主体。2002年后,工业建筑成为建筑改造的主体。1997到2008年,不同高度类型的建筑更替顺序为:平房→低层建筑→多层建筑。新增建筑先以低层为主,后以中高层,逐渐以高层为主。建筑改造在空间上并不是随机分布的,而是存在显著的空间正相关关系。在局部空间范围内,建筑改造呈现成片集中改造的现象。     

城市住区绿化生态效益及其可控影响因素的量化分析

基于杭州城西2007年1 m×1 m高分辨率航空遥感图像和夏季30 m×30 m LandsatTM数据,应用GIS和遥感图像解译方法定量计算了代表杭州城西30个典型城市住区总体生态效益的归一化植被指数(NDVI),以及各样本住区6个可控生态效益的影响指标(复层结构高度、软硬比、绿化覆盖率、容积率、绿地面积、建筑密度),并采用多元线性回归和对应分析方法得出6个影响因素对绿化生态效益的贡献度排序,以及提升住区生态效益的措施,分析了城市住区生态效益与典型可控影响因素间的定量关系.结果表明:各影响因素对城市住区生态效益贡献度依次为复层结构高度＞软硬比＞绿化覆盖率＞容积率＞绿地面积＞建筑密度;复层结构高度的贡献率远超过其他因素,建筑密度对住区生态效益的影响极微弱.利用对应分析法所得的各影响因素改进二维图,可方便地用来制定提升住区绿化生态效益的决策方案.     

An indicator quantitatively comparing two treatment effect sizes on responder and non-responder groups – exponential of estimated interaction parameter

 Sometimes a specific treatment is effective in one subgroup but not in another. An indicator allowing quantitative comparison of treatment effect in two subgroups would be useful in clinical medicine. We have developed such an indicator. It is obtained by calculations using Cox’s proportional hazard or logistic model with therapy, subgroup, and confounding explanatory variables. The parameter of the interaction between therapy and subgroup can be estimated and tested statistically. The exponential value of the interaction parameter is what we tentatively call the “hazard ratio ratio”, meaning the ratio between the treatment effects in two subgroups. The 95% confidence interval of the indicator can also be calculated. As a numerical example, the hazard ratio between the survival times of postoperative gastric cancer patients treated by adjuvant immunochemotherapy and patients without adjuvant immunochemotherapy in a subgroup with high serum glycosidically bound sialic acid (SA) level was lower than that in a low-SA subgroup using an estimate for hazard ratio ratio of less than 0.5 with statistical significance. We propose this indicator be used as a “responder/non-responder ratio” of therapy effect. Received: 11 April 1995 / Accepted: 5 September 1995     

Optimal approximate conversions of odds ratios and hazard ratios to risk ratios

Odds ratios approximate risk ratios when the outcome under consideration is rare but can diverge substantially from risk ratios when the outcome is common. In this paper, we derive optimal analytic conversions of odds ratios and hazard ratios to risk ratios that are minimax for the bias ratio when outcome probabilities are specified to fall in any fixed interval. The results for hazard ratios are derived under a proportional hazard assumption for the exposure. For outcome probabilities specified to lie in symmetric intervals centered around 0.5, it is shown that the square-root transformation of the odds ratio is the optimal minimax conversion for the risk ratio. General results for any nonsymmetric interval are given both for odds ratio and for hazard ratio conversions. The results are principally useful when odds ratios or hazard ratios are reported in papers, and the reader does not have access to the data or to information about the overall outcome prevalence.     

Assessing Space Heating Demandon a Regional Level: Evaluation of a Bottom‐Up Model in the Scope of a Case Study

The residential sector constitutes a major energy consumer, particularly on account of its needs for space heating. Offering a high leverage potential, this sector is a suitable starting point for greenhouse gas mitigation policies. By providing predictions of the energy demand of building stocks, bottom‐up building energy models represent a first step toward deriving strategies for abatement of detrimental effects related to housing energy use. This article aims at evaluating the performance of a simplified bottom‐up housing energy model. A global sensitivity analysis was performed to study the model's structure and the impact of individual model parameters. Moreover, an extensive final energy consumption data set allowed for an in‐depth comparison of this model with primary data in the scope of a case study in a Swiss municipality. On an individual building scale, the model fails to accurately simulate the energy demand. Deviations can be attributed to a range of factors, such as variability in occupants’ behavior and problems of representativeness in the underlying statistical database. Nevertheless, such under‐ or overestimations level off on an aggregated scale. In particular, the model reproduces the overall characteristics of the residential building stock's heating demand well. It is therefore well suited as a building stock model and provides a promising basis for an extended assessment of housing energy demands. In future research work, we will apply this model to a larger region in order to study various types of settlements from a life cycle perspective and to derive targeted measures aimed at reducing environmental impacts.     

Clinical significance of preoperative neutrophil-lymphocyte versus platelet-lymphocyte ratio in patients with operable colorectal cancer

The objective of this study was to clarify whether the neutrophil-lymphocyte ratio (NLR) and the platelet-lymphocyte ratio (PLR) are significant prognostic markers in patients with resectable colorectal cancer (CRC). A total of 200 patients who underwent curative resection for CRC were enrolled. The NLR and PLR were positively correlated (p?<?0.001). Both the NLR and PLR were shown to be good prognostic biomarkers of overall survival (OS) (p?=?0.002 and p?=?0.001, respectively). The PLR was an independent prognostic factor of OS based on multivariate analysis (hazard ratio, 1.971; 95% confidence interval, 1.102–3.335; p?=?0.021).     

Accuracy and Power of the Likelihood Ratio Test for Comparing Evolutionary Rates Among Genes

Sequences for multiple protein-coding genes are now commonly available from several, often closely related species. These data sets offer intriguing opportunities to test hypotheses regarding whether different types of genes evolve under different selective pressures. Although maximum likelihood (ML) models of codon substitution that are suitable for such analyses have been developed, little is known about the statistical properties of these tests. We use a previously developed fixed-sites model and computer simulations to examine the accuracy and power of the likelihood ratio test (LRT) in comparing the nonsynonymous-to-synonymous substitution rate ratio (=dN/dS) between two genes. Our results show that the LRT applied to fixed-sites models may be inaccurate in some cases when setting significance thresholds using a ² approximation. Instead, we use a parametric bootstrap to describe the distribution of the LRT statistic for fixed-sites models and examine the power of the test as a function of sampling variables and properties of the genes under study. We find that the power of the test is high (>80%) even when sampling few taxa (e.g., six species) if sequences are sufficiently diverged and the test is largely unaffected by the tree topology used to simulate data. Our simulations show fixed-sites models are suitable for comparing substitution parameters among genes evolving under even strong evolutionary constraint ( 0.05), although relative rate differences of 25% or less may be difficult to detect.Reviewing Editor: Dr. Rosmus Nielsen     

Reproductive success,spontaneous embryo abortion,and genetic load in flowering plants

Summary Reproductive success is divided into two phases: preemergent (the number of viable seeds that enter the ambient environment) and postemergent (the percentage of progeny that survive to reproduce). We studied preemergent reproductive success (PERS) in flowering plants by measuring the fruit/flower (Fr/Fl) ratio and the seed/ovule (S/O) ratio in a number of species of outcrossing and inbreeding plants, where PERS=the product of (Fr/Fl) and (S/O). In order to determine the influence of the ambient environment (including resource availability) we studied pairs of outcrossing and inbreeding species occurring in the same habitat. Among outcrossing species PERS averaged about 22%, whereas in inbreeding species the average was approximately 90%. The progeny/zygote (P/Z) ratio was studied in hand-pollinated populations in Epilobium angustifolium (a strongly outcrossing species) from populations in Oregon and Utah, by direct observation of embryogenesis at twoday intervals throughout the course of seed development. The P/Z ratio in both populations averaged near 30%, and the developing embryos showed a surprising array of abnormalities that resulted in embryo death. During early development >95% of the ovules had normally developing globular embryos, but beginning with differentiation (cotyledon formation) about 70% of the original globular embryos aborted during the course of embryogenesis and seed development. The clustering of developmental lethals during peroids of major differentiation events parallels the animal model of development. We found little evidence that PERS was limited by the ambient environment (including resource availability), pollination, or factors associated with the inbreeding habit. Instead, PERS was found to be inextricably linked to outcrossing plants, whose breeding systems promote genetic variability. The high incidence of developmental lethals in E. angustifolium and the resulting low P/Z ratio (ca. 30%) is attributed to genetic load (any lethal mutation or allelic combination) possibly working in combination with developmental selection (interovarian competition among genetically diverse embryos). Examples of maternally controlled, fixed patterns of ovule abortion with respect to position or number are discussed. However, we found no need to employ female choice as a hypothesis to explain our results for the extensive, seemingly random patterns of embryo abortion in E. angustifolium and other outcrossing species. A more parsimonious, mechanistic explanation based on genetic load-developmental selection is sufficient to account for the differential survivorship of embryos. Likewise, the traditional concept of a positive growth regulator feedback system based on the number of surviving ovules in an ovary can account for subsequent fruit survivorship.     

乳白蚁不同品级的比例

乳白蚁Coptotermes在湖北宜昌地区每年11月～次年3月收集到的巢群,每年品级比例基本平衡。品级头比的数据一律来自1月份的巢群;品级重比是11月～次年3月的巢群。品级的比例分别为：工蚁占81．70％、干重比69．45％;兵蚁占7．50％、干重比7．69％;生殖蚁占10．80％、干重比26．76％。