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1Remarks on Urban Spatial Growth Management ResearchCHEN Jinfu,Professor,Director,Teaching & Research Office on Urban Planning,Architecture and Urban Planning School,Huazhong University of Science and Technology PhD Candidate,College of Public Administration,Huazhong University of Science and Technology,Wuhan,P.R.China.REN Lijuan,Postgraduate,Architecture and Urban Planning School,Huazhong University of Science and Technology,Wuhan,P.R.China.YU Cheng,Postgraduate,Architecture and Urban Planning School,Huazhong University of Science and Technology,Wuhan,P.R.China.XU Xiaolei,Postgraduate,Architecture and Urban Planning School,Huazhong University of Science and Technology,Wuhan,P.R.China.LI Xinyan,Lecturer,Architecture and Urban Planning School,Huazhong University of Science and Technology,Wuhan,P.R.China. 2010China City Planning Review2010,19,2:180
2Biomass carbon stocks in China's forests between 2000 and 2050:A prediction based on forest biomass-age relationships显示文摘China's forests are characterized by young forest age,low carbon density and a large area of planted forests,and thus have high potential to act as carbon sinks in the future.Using China's national forest inventory data during 1994-1998 and 1999-2003,and direct field measurements,we investigated the relationships between forest biomass density and forest age for 36 major forest types.Statistical approaches and the predicted future forest area from the national forestry development plan were applied to estimate the potential of forest biomass carbon storage in China during 2000-2050.Under an assumption of continuous natural forest growth,China's existing forest biomass carbon(C) stock would increase from 5.86 Pg C(1 Pg=1015 g) in 1999-2003 to 10.23 Pg C in 2050,resulting in a total increase of 4.37 Pg C.Newly planted forests through afforestation and reforestation will sequestrate an additional 2.86 Pg C in biomass.Overall,China's forests will potentially act as a carbon sink for 7.23 Pg C during the period 2000-2050,with an average carbon sink of 0.14 Pg C yr-1.This suggests that China's forests will be a significant carbon sink in the next 50 years.XU Bing,GUO ZhaoDi,PIAO ShiLong & FANG JingYun* Department of Ecology,College of Urban and Environmental Sciences,and Key Laboratory for Earth Surface Processes of the Ministry of Education,Peking University,Beijing 100871,China 2010Science China(Life Sciences)2010,53,7:61
3前方牵引器治疗安氏Ⅲ类错畸形—20例病例临床分析显示文摘目的 分析替牙期前方牵引器矫治安氏Ⅲ类错前牙反中骨性和牙性变化。方法 选择2 0例安氏Ⅲ类错前牙反患者 ,在替牙早期使用前方牵引器 ,治疗开始、治疗结束及治疗结束后一年拍摄头颇侧位片 ,并以Pancherz分析法进行头影测量分析。结果 表明 ,在治疗刚刚结束时 ,覆盖增加 6 5毫米 ,其中 40 %为骨性变化 ,6 0 %为牙性代偿。治疗结束后一年发现覆盖减少 1 2毫米 ,即骨性变化占 2 3% ,牙性代偿 77%。谷岩 A.Bakr M.Rabie Urban Hgg 2000口腔正畸学2000,7,3:59
4Viral and cellular determinants involved in hepadnaviral entry显示文摘Hepadnaviridae is a family of hepatotropic DNA viruses that is divided into the genera orthohepadnavirus of mammals and avihepadnavirus of birds.All members of this family can cause acute and chronic hepatic infec-tion,which in the case of human hepatitis B virus(HBV) constitutes a major global health problem.Although our knowledge about the molecular biology of these highly liver-specific viruses has profoundly increased in the last two decades,the mechanisms of attachment and productive entrance into the differentiated host hepa-tocytes are still enigmatic.The difficulties in studying hepadnaviral entry were primarily caused by the lack of easily accessible in vitro infection systems.Thus,for more than twenty years,differentiated primary hepato-cytes from the respective species were the only in vitro models for both orthohepadnaviruses(e.g.HBV) and avihepadnaviruses(e.g.duck hepatitis B virus [DHBV]).Two important discoveries have been made recently re-garding HBV:(1) primary hepatocytes from tree-shrews;i.e.,Tupaia belangeri,can be substituted for primary hu-man hepatocytes,and(2) a human hepatoma cell line(HepaRG) was established that gains susceptibility for HBV infection upon induction of differentiation in vitro.A number of potential HBV receptor candidates have been described in the past,but none of them have been confirmed to function as a receptor.For DHBV and prob-ably all other avian hepadnaviruses,carboxypeptidase D(CPD) has been shown to be indispensable for infection,although the exact role of this molecule is still under debate.While still restricted to the use of primary duck hepatocytes(PDH),investigations performed with DHBV provided important general concepts on the first steps of hepadnaviral infection.However,with emerging dataobtained from the new HBV infection systems,the hope that DHBV utilizes the same mechanism as HBV only partially held true.Nevertheless,both HBV and DHBV in vitro infection systems will help to:(1) functionally dis-sect the hepadnaviral entry pathways,(2) perform re-verse genetics(e.g.test the fitness of escape mutants),(3) titrate and map neutralizing antibodies,(4) improve current vaccines to combat acute and chronic infections of hepatitis B,and(5) develop entry inhibitors for future clinical applications.Dieter Glebe Stephan Urban 2007World Journal of Gastroenterology2007,13,1:35
5Above-and belowground biomass in relation to envi- ronmental factors in temperate grasslands, Inner Mongolia显示文摘Above- and belowground biomasses of grasslands are important parameters for characterizing re- gional and global carbon cycles in grassland ecosystems. Compared with the relatively detailed in- formation for aboveground biomass (AGB), belowground biomass (BGB) is poorly reported at the re- gional scales. The present study, based on a total of 113 sampling sites in temperate grassland of the Inner Mongolia, investigated regional distribution patterns of AGB, BGB, vertical distribution of roots, and their relationships with environmental factors. AGB and BGB increased from the southwest to the northeast of the study region. The largest biomass occurred in meadow steppe, with mean AGB and BGB of 196.7 and 1385.2 g/m2, respectively; while the lowest biomass occurred in desert steppe, with an AGB of 56.6 g/m2 and a BGB of 301.0 g/m2. In addition, about 47% of root biomass was distributed in the top 10 cm soil. Further statistical analysis indicated that precipitation was the primary determinant factor in shaping these distribution patterns. Vertical distribution of roots was significantly affected by precipitation, while the effects of soil texture and grassland types were weak.MA WenHong1,2, YANG YuanHe1, HE JinSheng1, ZENG Hui1,2 & FANG JingYun1 1 Department of Ecology, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China 2 School of Environment & Urban Study, Peking University Shenzhen Graduate School, Shenzhen 518055, China 2008Science China(Life Sciences)2008,51,3:34
6我国城市生活垃圾处理行业2012年发展综述显示文摘综述了2011年我国生活垃圾处理的发展概况,以及2012年国家发布和实施的有关标准和政策;重点介绍并分析了2012年国内新投入运行的生活垃圾焚烧发电厂和垃圾综合处理厂;对城市生活垃圾处理行业的发展进行了展望。(Disposal Committee of Urban Domestic Refuse,CAEPI,Beijing 100037,China) 2013中国环保产业2013,,3:31
7Enhanced anaerobic biodegradability of real coal gasification wastewater with methanol addition显示文摘Coal gasification effluent is a typical refractory industrial wastewater with a very poor anaerobic biodegradability due to its toxicity.Methanol was introduced to improve anaerobic biodegradability of real coal gasification wastewater,and the effect of methanol addition on the performance was investigated in a mesophilic upflow anaerobic sludge bed reactor with a hydraulic retention time of 24 hr.Experimental results indicated that anaerobic treatment of coal gasification wastewater was feasible with the addition of methanol.The corresponding maximum COD and phenol removal rates were 71% and 75%,respectively,with methanol concentration of 500 mg COD/L for a total organic loading rate of 3.5 kg COD/(m3 ·day) and a phenol loading rate of 0.6 kg/(m3 ·day).The phenol removal rate was not improved with a higher methanol concentration of 1000 mg COD/L.Substrate utilization rate (SUR) tests indicated that the SURs of phenol were 106,132,and 83 mg phenol/(g VSS·day) at methanol concentrations of 250,500,and 1000 mg COD/L,respectively,and only 45 mg phenol/(g VSS·day) in the control reactor.The presence of methanol could reduce the toxicity of coal gasification wastewater and increase the biodegradation of phenolic compounds.Wei Wang,Hongjun Han,Min Yuan,Huiqiang Li State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology,Harbin 150090,China 2010Journal of Environmental Sciences2010,22,12:25
8Quantitative relationships between vegetation and several pollen taxa in surface soil from North China显示文摘According to the vegetation investigation and pollen analysis of surface samples sampled along a precipitation gradient of the Northeast China Transect (NECT), several pollen taxa, including Pinus, Betula, Quercus, Tilia, Acer, Ulmus, Artemisia, Chenopodiaceae, Gramineae and Cyperaceae, were chosen to make the regression and correlation analyses. The results indicated that there exists a close relationship between vegetation and pollen taxa in surface samples. The regression parameters for ten taxa in the forests in the eastern part of NECT were different from those in the steppes in the western part. Pinus, Betula, Artemisia and Chenopodiaceae, which have large slope and y-intercept terms, were over-representative taxa. Acer, Gramineae and Cyperaceae, which have small slope and y-intercept terms, were under-representative taxa. Quercus, Tilia and Ulmus whose slope terms have negative correlation with y-intercept terms were equi-representative taxa. The pollen taxa with large slope or large y-interceptLI Yiyin, ZHANG Xinshi & ZHOU Guangsheng1. Department of Urbon and Environmental Sciences, Peking University, Beijing 100871, China 2. Laboratory of Quantitative Vegetation Ecology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China 3. School of Urban and Environmental Sciences, Northeast Normal University, Changchun 130024, China Correspondence should be addressed to Li Yiyin 2000Chinese Science Bulletin2000,45,16:24
9我国城市生活垃圾处理行业2010年发展综述显示文摘简述了2010年我国城市生活垃圾处理的总体状况;归纳了2010年国家发布和实施的有关标准和政策;介绍了2010年新批准申请CDM的填埋气体利用项目和垃圾焚烧发电项目、垃圾堆肥项目,以及新投入运行的生活垃圾焚烧发电厂;对城市生活垃圾处理行业的发展进行了展望。(Committee of Urban Domestic Refuge Disposal of CAEPI,Beijing 100037,China) 2011中国环保产业2011,,4:23
10Biomass and carbon dynamics of a tropical mountain rain forest in China显示文摘Biometric inventories for 25 years,from 1983 to 2005,indicated that the Jianfengling tropical mountain rain forest in Hainan,China,was either a source or a modest sink of carbon.Overall,this forest was a small carbon sink with an accumulation rate of(0.56±0.22) Mg C ha-1yr-1,integrated from the long-term measurement data of two plots(P9201 and P8302).These findings were similar to those for African and American rain forests((0.62±0.23) Mg C ha-1yr-1).The carbon density varied between(201.43±29.38) Mg C ha-1 and(229.16±39.2) Mg C ha-1,and averaged(214.17±32.42) Mg C ha-1 for plot P9201.Plot P8302,however,varied between(223.95±45.92) Mg C ha-1 and(254.85±48.86) Mg C ha-1,and averaged(243.35±47.64) Mg C ha-1.Quadratic relationships were found between the strength of carbon sequestration and heavy rainstorms and dry months.Precipitation and evapotranspiration are two major factors controlling carbon sequestration in the tropical mountain rain forest.CHEN DeXiang1*,LI YiDe1,LIU HePing2,XU Han1,XIAO WenFa3,LUO TuShou1,ZHOU Zhang4 & LIN MingXian1 1Research Institute of Tropical Forestry,Chinese Academy of Forestry,Guangzhou 510520,China 2Department of Physics,Atmospheric Science and Geoscience,Jackson State University,MS 39217,USA 3Research Institute of Forest Ecology,Environment and Protection,Chinese Academy of Forestry,Beijing 100091,China 4Department of Ecology,College of Urban and Environmental Sciences,Peking University,Beijing 100872,China 2010Science China(Life Sciences)2010,53,7:20
11我国城市生活垃圾处理行业2013年发展综述显示文摘综述了2012年我国城市生活垃圾处理行业的发展概况,以及2013年国家发布和实施的有关标准和政策;重点介绍了2013年国内新投入运行的生活垃圾焚烧发电厂和垃圾综合处理厂;归纳了2013年国内促进行业发展的部分重要事件;对城市生活垃圾处理行业的发展进行了展望。Specialized Committee of Urban Domestic Refuse of CAEPI 2014中国环保产业2014,0,12:18
12Monitoring microbial community structure and succession of an A/O SBR during start-up period using PCR-DGGE显示文摘Polymerase chain reaction(PCR)-denaturing gradient gel electrophoresis(DGGE) protocol was employed for revealing microbial community structure and succession in a sequential anaerobic and aerobic reactor performing enhanced biological phosphorus removal(EBPR) during start-up period.High phosphorus removal was achieved after 15 d.On day 30,phosphorus removal effciency reached to 83.2% and the start-up was finished.DGGE profiles of periodical sludge samples showed that dominant microbial species were 19 OTUs(operational taxonomy units).Unweighted pair-group method using arithmetic averages(UPGMA) clustering analysis revealed that rapid community succession correlated to low phosphorus removal rate and high phosphorus removal effciency reflected on steady community structure.Sequencing results indicated that determined sequences(12 OTUs) belonged to Proteobacterium,Actinobacteria,Gemmatimonadales and unaffiliate group.Proteobacterium,Tetrasphaera elongate and Gemmatimonas aurantiaca may act important roles in phosphorus removal.With little amount as known glycogen accumulating organisms,Candidatus Competibacter phosphatis still at accumulating-phase had limited effect on microbial community structure.When climax community was obtained,dominant microbes were 14 OTUs.Microbes in a large amount were uncultured bacterium Thauera sp.,uncultured γ-Proteobacterium and Tetrasphaera elongata.WANG Xiuheng,ZHANG Kun,REN Nanqi,LI Nan,REN Lijiao State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology,Harbin 150090,China. 2009Journal of Environmental Sciences2009,21,2:17
13Lie symmetries of mechanical systems with unilateral holonomic constraints显示文摘In the recent twenty years, the study on the Lie symmetries and conserved quantities of constrained mechanical systems has been making great progress[1-5]. Up to now, however, all the studies are limited to the mechanical systems with ideal bilateral constraints. This note further studies the Lie symmetries of mechanical systems with unilateral holonomic constraints, and two problems of Lie symmetries for the systems are put forward and solved, i.e. finding the conserved quantity from a Lie symmetric transformation of the system and finding the corresponding Liesymmetry from an integral of the systemi ? 梛 ? Jsymmetry from an integral of the system.ZHANG Yi & MEI Fengxiang1. Department of Basic Courses, Suzhou Institute of Urban Construction & Environmental Protection, Suzhou 215011, China 2. Department of Applied Mechanics, Beijing Institute of Technology, Beijing 10008I, China 2000Chinese Science Bulletin2000,45,15:15
14Residual or recurrent cerebellar low-grade glioma in children after tumor resection: is re-treatment needed? A single center experience from 1983 to 2003显示文摘Benesch M Eder HG Sovinz P Raith J Lackner H Moser A Urban C 2006中国神经肿瘤杂志2006,4,3:15
15Distribution and health risk assessment of organochlorine pesticides(OCPs) in industrial site soils:A case study of urban renewal in Beijing,China显示文摘A field survey was conducted in a contaminated industrial site of southern Beijing,China to investigate the contents and distribution of the organochlorine pesticides(α-,β-,γ-,δ-HCH,p,p-DDT,p,p-DDE,p,p-DDD and o,p-DDT) in the profiles of soil,and a health risk assessment was carried out with CalTOX multimedia exposure model.Results showed that mean concentrations of total hexachlorocyclohexane isomers(HCHs) and total dichlorodiphenyltrichloroethane isomers(DDXs) in soils were in the range of 13.20-148.71 mg/kg,and 3.02-67.43 mg/kg,respectively.Organochlorine pesticides(OCPs) content peaked in the surface and declined in soil profile with depth.The amounts of HCHs in three profiles of soil were larger than DDXs.Composition analysis indicated that there was a trend of degradation of OCPs in the site,but the mean of HCHs and DDXs concentration were over the state warning standard limit(HCHs,0.50 mg/kg;DDXs,0.50 mg/kg).According to current land use development,health risk assessment with CalTOX and Monte Carlo analysis showed that health risks mainly came from two exposure pathways:dermal uptake and inhalation,and the total risk values all exceeded the general acceptable health risk value(10-6).The sensitivity analysis indicated that five parameters significantly contributed to total risk.YANG Wenrui,WANG Rusong,ZHOU Chuanbin,LI FengState key laboratory of Urban and Regional Ecology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China. 2009Journal of Environmental Sciences2009,21,3:14
16Microbial community structure in an integrated A/O reactor treating diluted livestock wastewater during start-up period显示文摘In order to investigate the correlation between reactor performance and the microorganisms,an integrated A/O reactor was operated for 72 days to treat diluted livestock wastewater.Chemical oxygen demand (COD) removal efficiency increased from 79% to 94%,with total nitrogen (TN) removal efficiency from 37% to 50% (HRT 7.4 hr) when the influent COD and TN were ca.1500 mg/L and 95 mg/L,respectively,and the outlet COD concentration was less than 100 mg/L at the end.Microbial community was monitored during start-up period by denaturing gradient gel electrophoresis (DGGE) based on 16S rRNA gene.DGGE profiles showed that microbial community had changed significantly during the start-up and these shifts were in accordance with the reactor performance.UPGMA clustering analysis showed that 14 anaerobic samples fell into five main groups and so did the aerobic ones,but the grouping patterns were different.Phylogenetic analysis indicated that microbial populations in the anaerobic compartment belonged to Firmicutes,Proteobacteria,Chloroflexi and Bacteroidetes,while Proteobacteria,Bacteroidetes,Firmicutes,Verrucomicrobiae and Nitrospira were present in the aerobic compartment.In the anaerobic compartment,more fermentative and acetogenic bacteria were detected during the start-up while denitrifying bacteria faded away.Two functional populations such as Nitrospira defluvii and Dechloromonas denitrificans were observed when nitrogen removal was high,indicating that simultaneous nitrification and denitrification occurred in the aerobic compartment.Lijiao Ren,Yining Wu,Nanqi Ren,Kun Zhang,Defeng Xing State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology,Harbin 150090,China. 2010Journal of Environmental Sciences2010,22,5:14
17Endoscopic mucosal resection and endoscopic submucosal dissection in the treatment of sporadic nonampullary duodenal adenomatous polyps显示文摘Although uncommon, sporadic nonampullary duodenal adenomas have a growing detection due to the widespread of endoscopy. Endoscopic therapy is being increasingly used for these lesions, since surgery, considered the standard treatment, carries significant morbidity and mortality. However, the knowledge about its risks and benefits is limited, which contributes to the current absence of standardized recommendations. This review aims to discuss the efficacy and safety of endoscopic mucosal resection(EMR) and endoscopic submucosal dissection(ESD) in the treatment of these lesions. A literature review was performed, using the Pubmed database with the query: '(duodenum or duodenal)(endoscopy or endoscopic) adenoma resection', in the human species and in English. Of the 189 retrieved articles, and after reading their abstracts, 19 were selected due to their scientific interest. The analysis of their references, led to the inclusion of 23 more articles for their relevance in this subject. The increased use of EMR in the duodenum has shown good results with complete resection rates exceeding 80% and low complication risk(delayed bleeding in less than 12% of the procedures). Although rarely used in the duodenum, ESD achieves close to 100% complete resection rates, but is associated with perforation and bleeding risk in up to one third of the cases. Even though literature is insufficient to draw definitive conclusions, studies suggest that EMR and ESD are valid options for the treatment of nonampullary adenomas. Thus, strategies to improve these techniques, and consequently increase the effectiveness and safety of the resection of these lesions, should be developed.Joana Marques Francisco Baldaque-Silva Pedro Pereira Urban Arnelo Naohisa Yahagi Guilherme Macedo 2015World Journal of Gastrointestinal Endoscopy2015,7,7:13
18Research on Methods of Ecological Security Assessment of the Middle and Lower Reaches of Liaohe River Based on GIS显示文摘Ecological security assessment and early warning research possess the attributes of spatiality, non-linearity and randomicity, so we must process much spatial information. Spatial analysis and data management are the advantages of GIS, which can define distribution trend and spatial relations of environmental factors, and show ecological security pattern graphically. Spatial differences of ecological security assessment based on GIS are discussed in this paper, of which the middle and lower reaches of the Liaohe River is taken as a study case. First, to work out pressure-state-response (P-S-R) assessment indicators system, and investigate in person and gather information; second, to digitize the watershed; third, to quantize and calculate by the fuzzy method; last, to construct GIS grid database, and expound spatial differences of ecological security by GIS interpolation and assembly analysis.Wang Geng 1,2 , Nie Baochi 3, Wang Lin 1 & Wu Wei 1 1. School of Environmental and Biological Science and Technology, Dalian University of Technology, Dalian 116024, China 2. Urban and Environmental School, Liaoning Normal University, Dalian 116029, China 3. Shenyang Buraue of Water Resources, Shenyang 110013, China. 2005Chinese Journal of Population,Resources and Environment2005,3,4:12
19Herbst矫治器伴头帽牵引治疗安氏Ⅱ类错显示文摘目的 研究Herbst矫治器伴头帽牵引逐步前伸下颌对安氏Ⅱ类错的矫治效果。方法 治疗组 2 2例患者 ,对照组 31例患者。治疗组患者均按治疗的前 6个月、后 6个月 (平均 )及维持期 6个月 ,3个阶段治疗并拍摄头侧位定位片观察。对照组患者拍摄 2次头侧位定位片 ,其间间隔 6个月。结果 平均治疗 12个月后的疗效是抑制上颌骨生长、刺激下颌骨生长并降低下面高。与对照组相比 ,对上颌骨的抑制作用在治疗的前后 6个月均有统计学意义 ,对下颌骨的刺激作用仅在治疗前 6个月有统计学意义 ,对下面高的降低作用仅在治疗后 6个月有统计学意义。维持阶段上下基骨关系不变而对下面高的降低作用进一步加强。结论 Herbst矫治器伴头帽牵引能有效地矫治安氏Ⅱ类错 ,对上颌骨的作用随时间的增加而加强 。杜熹 Urban Hgg 2004华西口腔医学杂志2004,22,1:12
20A decision-making model of development intensity based on similarity relationship between land attributes intervened by urban design显示文摘The paper presents a dynamic model intervened by urban design for the decision-making of land development intensity, which expresses the inherent interaction mechanism between lands based on the evaluation of land attributes and their similarity relationship. Each land unit is described with several factors according to their condition and potential for development, such as land function, accessibility, historical site control, landscape control, and so on. Then, the dynamic reference relationship between land units is established according to the similarity relationship between their factors. That means lands with similar conditions tend to have similar development intensities, which expresses the rule of the spontaneous urban development. Therefore, the development intensities of the pending lands can be calculated by the confirmed ones. Furthermore, the system can be actively intervened by adjusting the parameters according to urban design or planning intentions. And the reaction of the system offers effective support and reference for reasonable decision. The system with multiple intervention input is not only a credible tool for deriving development intensities, but also a platform to activate urban design conception. Above all, the system as a socio-technical tool integrates the optimization of form, function and environment, and embodies the principle of impersonality, justice and flexibility in the decision of land development intensity.WANG JianGuo1, ZHANG Yu2 & FENG Han3 1 School of Architecture, Southeast University Key Laboratory for Urban and Architectural Heritage Conservation, Ministry of Education, Nanjing 210096, China 2 School of Architecture, Southeast University, Nanjing 210096, China 3 Faculty of Architecture, Delft University of Technology, 2628 CR Delft, Netherlands 2010Science China(Technological Sciences)2010,53,7:12
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