921 resultados para 75<48>US
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"March 1962."
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"June 1962."
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When asking the question, ``How can institutions design science policies for the benefit of decision makers?'' Sarewitz and Pielke Sarewitz, D., Pielke Jr., R.A., this issue. The neglected heart of science policy: reconciling supply of and demand for science. Environ. Sci. Policy 10] posit the idea of ``reconciling supply and demand of science'' as a conceptual tool for assessment of science programs. We apply the concept to the U.S. Department of Agriculture's (USDA) carbon cycle science program. By evaluating the information needs of decision makers, or the ``demand'', along with the supply of information by the USDA, we can ascertain where matches between supply and demand exist, and where science policies might miss opportunities. We report the results of contextual mapping and of interviews with scientists at the USDA to evaluate the production and use of current agricultural global change research, which has the stated goal of providing ``optimal benefit'' to decision makers on all levels. We conclude that the USDA possesses formal and informal mechanisms by which scientists evaluate the needs of users, ranging from individual producers to Congress and the President. National-level demands for carbon cycle science evolve as national and international policies are explored. Current carbon cycle science is largely derived from those discussions and thus anticipates the information needs of producers. However, without firm agricultural carbon policies, such information is currently unimportant to producers. (C) 2006 Elsevier Ltd. All rights reserved.
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Statement: Jams, Jelly Beans and the Fruits of Passion Let us search, instead, for an epistemology of practice implicit in the artistic, intuitive processes which some practitioners do bring to situations of uncertainty, instability, uniqueness, and value conflict. (Schön 1983, p40) Game On was born out of the idea of creative community; finding, networking, supporting and inspiring the people behind the face of an industry, those in the mist of the machine and those intending to join. We understood this moment to be a pivotal opportunity to nurture a new emerging form of game making, in an era of change, where the old industry models were proving to be unsustainable. As soon as we started putting people into a room under pressure, to make something in 48hrs, a whole pile of evolutionary creative responses emerged. People refashioned their craft in a moment of intense creativity that demanded different ways of working, an adaptive approach to the craft of making games – small – fast – indie. An event like the 48hrs forces participants’ attention on the process as much as the outcome. As one game industry professional taking part in a challenge for the first time observed: there are three paths in the genesis from idea to finished work: the path that focuses on mechanics; the path that focuses on team structure and roles and the path that focuses on the idea, the spirit – and the more successful teams need to put the spirit of the work first and foremost. The spirit drives the adaptation, it becomes improvisation. As Schön says: “Improvisation consists on varying, combining and recombining a set of figures within the schema which bounds and gives coherence to the performance.” (1983, p55). This improvisational approach is all about those making the games: the people and the principles of their creative process. This documentation evidences the intensity of their passion, determination and the shit that they are prepared to put themselves through to achieve their goal – to win a cup full of jellybeans and make a working game in 48hrs. 48hr is a project where, on all levels, analogue meets digital. This concept was further explored through the documentation process. This set of four videos were created by Cameron Owen on the fly during the challenge using both the iphone video camera and editing software in order to be available with immediacy and allow the event audience to share the experience - and perhaps to give some insights into the creative process exposed by the 48 hour challenge. ____________________________ Schön, D. A. 1983, The Reflective Practitioner: How Professionals Think in Action, Basic Books, New York
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The 48-hour game making challenge started out in 2007 as a creative community event. We have run this event each year since and seen over 120 games made. 2011 was the most remarkable in that each of the 20 teams made a playable game – the shape of the challenge has changed …. We have invested in the process of reflective practice & action research, with the event being part of a sweep of programs that inform this research, with each year giving us fresh insights into both the creative practice and essential concerns, process and trends of the independent games industry creative community, which we then respond to within our curatorial development of the subsequent programming. The 2011 48-hour challenge research project focused on the people and the site. We were specifically interested in the manner in which the community occupied the creative space.
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We have always felt that “something very special” was happening in the 48hr and other similar game jams. This “something” is more than the intensity and challenge of the experience, although this certainly has appeal for the participants. We had an intuition that these intense 48 hour game jams exposed something pertinent to the changing shape of the Australian games industry where we see the demise of the late 20th century large studio - the “Night Elf” model and the growth of the small independent model. There are a large number of wider economic and cultural factors around this evolution but our interest is specifically in the change from “industry” to “creative industry” and the growth of games as a cultural media and art practice. If we are correct in our intuition, then illuminating this something also has important ramifications for those courses which teach game and interaction design and development. Rather than undertake a formal ethno-methodological approach, we decided to track as many of the actors in the event as possible. We documented the experience (Keith Novak’s beautiful B&W photography), the individual and their technology (IOGraph mouse tracking), the teams as a group (Time lapse photography) and movement tracking throughout the whole space (Blue tooth phone tracking). The raw data collected has given us opportunity to start a commentary on the “something special” happening in the 48hr.
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Background: Preterm birth is a major cause of neonatal morbidity and mortality, with 75% of preterm births occurring late preterm. Previous studies have investigated the microbial diversity within placentas delivered early preterm but there has been no investigation of the prevalence of bacteria, particularly Ureaplasma spp. in late preterm placentas. Method: Women giving birth late preterm (320 – 366 weeks of gestation) in Cincinnati were recruited for this study. Samples of chorioamnion were collected aseptically at the time of delivery, shipped to QUT and tested for Ureaplasma spp. and other bacteria by culture and/or PCR assays. The presence of bacteria was correlated with adverse pregnancy outcomes, including histological chorioamnionitis (tissue sections read by US pathologists). Results: To date, Ureaplasma spp. have been detected in 15/270 (5.5%) of placentas by culture and 19/270 (7%) by PCR. Ureaplasma presence correlated with histological chorioamnionitis (12/19%; 63%). However, the presence of other bacteria was not associated with chorioamnionitis (5%). Chorioamnionitis was unevenly distributed in ethnic groups, with a higher incidence in African-Americans’ (6/7; 86%), compared to Caucasians’ (6/12; 50%) who were colonised with ureaplasmas. Conclusion: This study is the first to report the prevalence of ureaplasmas in women (7%) who deliver late preterm. Ureaplasma spp. were associated with a higher incidence of chorioamnionitis (63% compared to 15% for non-infected women). This data strongly suggests that ureaplasmas are a cause of late preterm deliveries and African-American women are at greater risk of chorioamnionitis.
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In this paper we analyse two variants of SIMON family of light-weight block ciphers against variants of linear cryptanalysis and present the best linear cryptanalytic results on these variants of reduced-round SIMON to date. We propose a time-memory trade-off method that finds differential/linear trails for any permutation allowing low Hamming weight differential/linear trails. Our method combines low Hamming weight trails found by the correlation matrix representing the target permutation with heavy Hamming weight trails found using a Mixed Integer Programming model representing the target differential/linear trail. Our method enables us to find a 17-round linear approximation for SIMON-48 which is the best current linear approximation for SIMON-48. Using only the correlation matrix method, we are able to find a 14-round linear approximation for SIMON-32 which is also the current best linear approximation for SIMON-32. The presented linear approximations allow us to mount a 23-round key recovery attack on SIMON-32 and a 24-round Key recovery attack on SIMON-48/96 which are the current best results on SIMON-32 and SIMON-48. In addition we have an attack on 24 rounds of SIMON-32 with marginal complexity.
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Epidemiological studies have demonstrated associations between endometriosis and certain histotypes of ovarian cancer, including clear cell, low-grade serous and endometrioid carcinomas. We aimed to determine whether the observed associations might be due to shared genetic aetiology. To address this, we used two endometriosis datasets genotyped on common arrays with full-genome coverage (3194 cases and 7060 controls) and a large ovarian cancer dataset genotyped on the customized Illumina Infinium iSelect (iCOGS) arrays (10 065 cases and 21 663 controls). Previous work has suggested that a large number of genetic variants contribute to endometriosis and ovarian cancer (all histotypes combined) susceptibility. Here, using the iCOGS data, we confirmed polygenic architecture for most histotypes of ovarian cancer. This led us to evaluate if the polygenic effects are shared across diseases. We found evidence for shared genetic risks between endometriosis and all histotypes of ovarian cancer, except for the intestinal mucinous type. Clear cell carcinoma showed the strongest genetic correlation with endometriosis (0.51, 95% CI = 0.18–0.84). Endometrioid and low-grade serous carcinomas had similar correlation coefficients (0.48, 95% CI = 0.07–0.89 and 0.40, 95% CI = 0.05–0.75, respectively). High-grade serous carcinoma, which often arises from the fallopian tubes, showed a weaker genetic correlation with endometriosis (0.25, 95% CI = 0.11–0.39), despite the absence of a known epidemiological association. These results suggest that the epidemiological association between endometriosis and ovarian adenocarcinoma may be attributable to shared genetic susceptibility loci.
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Introdução: a apneia obstrutiva do sono (AOS) é considerada um fator de risco para as doenças cardiovasculares. Os mecanismos responsáveis pelo desenvolvimento da aterosclerose potencializados pela AOS não são completamente conhecidos. Entretanto, existem evidências de que a AOS está associada com aumento no estresse oxidativo, elevação nos mediadores inflamatórios, resistência à insulina, ativação do sistema nervoso simpático, elevação da pressão arterial (PA) e a disfunção endotelial. Objetivo: avaliar a relação da AOS com a função endotelial, o estresse oxidativo, os biomarcadores inflamatórios, o perfil metabólico, a adiposidade corporal, a atividade simpática e a PA em indivíduos obesos. Métodos: estudo transversal envolvendo 53 pacientes obesos, com índice de massa corporal (IMC) ≥ 30 e < 40 Kg/m2, sem distinção de raça e gênero, apresentando idade entre 20 e 55 anos. O estudo do sono foi realizado com o equipamento Watch-PAT 200, sendo feito o diagnóstico de AOS quando índice apneia-hipopneia (IAH) ≥ 5 eventos/h. Todos os participantes foram submetidos à avaliação do (a): adiposidade corporal (peso, % gordura corporal e circunferências da cintura, quadril e pescoço); PA; atividade do sistema nervoso simpático (concentrações plasmáticas de catecolaminas); biomarcadores inflamatórios (proteína C reativa ultrassensível (PCR-us) e adiponectina); estresse oxidativo (malondialdeído); metabolismo glicídico (glicose, insulina e HOMA-IR) e lipídico (colesterol total e frações e triglicerídeos); e função endotelial (índice de hiperemia reativa (RHI) avaliado com o equipamento Endo-PAT 2000 e moléculas de adesão celular). A análise estatística foi realizada com o software STATA versão 10. Resultados: dos 53 pacientes avaliados 20 foram alocados no grupo sem AOS (grupo controle; GC) (IAH: 2,550,35 eventos/h) e 33 no grupo com AOS (GAOS) (IAH: 20,163,57 eventos/h). A faixa etária (39,61,48 vs. 32,52,09 anos) e o percentual de participantes do gênero masculino (61% vs. 25%) foram significativamente maiores no GAOS do que no GC (p=0,01). O GAOS em comparação o GC apresentou valores significativamente mais elevados de circunferência do pescoço (CP) (40,980,63 vs. 38,650,75 cm; p=0,02), glicemia (92,541,97 vs. 80,21,92 mg/dL; p=0,0001), PA sistólica (126,051,61 vs.118,16 1,86 mmHg; p=0,003) e noradrenalina (0,160,02 vs. 0,120,03 ng/mL; p=0,02). Após ajustes para fatores de confundimento, a glicose e a PCR-us foram significativamente mais elevadas no GAOS. Os 2 grupos apresentaram valores semelhantes de IMC, insulina, HOMA-IR, perfil lipídico, adiponectina, PA diastólica, adrenalina, dopamina, moléculas de adesão celular e malondialdeído. A função endotelial avaliada pelo RHI também foi semelhante nos 2 grupos (GAOS:1,850,2 vs. GC:1,980,1; p=0,31). Nas análises de correlação, considerando todos os participantes do estudo, o IAH apresentou associação positiva e significativa com CP e PCR-us após ajustes para fatores de confundimento. A saturação mínima de O2 se associou de forma negativa e significativa com a CP, os níveis séricos de insulina e o HOMA-IR, mesmo após ajustes para fatores de confundimento. Conclusões: o presente estudo sugere que em obesos a AOS está associada com valores mais elevados de glicemia e inflamação; o aumento do IAH apresenta associação significativa com a obesidade central e com a inflamação; e a queda na saturação de oxigênio se associa com resistência à insulina.
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Segundo O`Kane et al, em 2008, foi demonstrado que 88,9% dos erros laboratoriais são realizados na fase pré-analítica. No laboratório de análises clínicas, o sistema de controle da qualidade pode ser definido como toda a ação sistemática necessária para dar confiança e segurança em todos os exames e prevenir a ocorrência de erros. O tempo de armazenamento pode variar de dias a meses ou mesmo anos, influenciando na definição da temperatura de estocagem. O armazenamento de longo prazo pode resultar na criopreservação inadequada para determinados analitos e pode desnaturar as lipoproteínas. Objetivos: Este trabalho teve como objetivo avaliar a fase pré-analítica, controle da qualidade interno e também avaliar o efeito do congelamento (- 80C) quanto ao tempo de armazenamento do soro e plasma de sangue colhido com ácido etilenodiamino tetra-acético (EDTA). As dosagens foram realizadas no Laboratório de Lípides LabLip, e estocadas em - 80 C por três anos, as mesmas foram redosadas no Serviço de Patologia Clínica da Policlínica Piquet Carneiro da UERJ com metodologias iguais e realizada a comparabilidade dos resultados. Foram analisados o perfil lipídico (CT, HDLc e TG) e PCR-US de 103 amostras, 73 no soro e 30 no plasma em dois laboratórios altamente qualificados. Discussão: Após redosagem foram encontrados nas dosagens de HDLc e CT resultados diminuídos respectivamente (correlação coeficiente no soro 0,48 e 0,62) teste t pareado no soro (CT p 0,0012 e HDLc p 0,0001). Conclusões: Os dados obtidos nas avaliações dos resultados de diferentes laboratórios e tempo de estocagem revelaram que as amostras quando armazenadas por um longo período após redosagem no soro, apresentaram diferenças em certos analitos, tais como CT e HDLc, no qual obteve-se resultados significativamente diminuídos, diferentemente no plasma, que após três anos de estocagem a -80C foram redosados e aplicados no teste t pareado, os analitos CT e PCR-US mantiveram a estabilidade.
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飞播是毛乌素沙地植被恢复与重建的重要手段。但此项技术仍存在一些问题,如飞播后成苗率较低等。柠条(Caragana korshinskii)、羊柴(Hedysarum laeve)、籽蒿(Artimisia sphaerocephala)与油蒿(Artimisia ordosica)是毛乌素沙地广泛分布的物种,也是飞播的主要物种。本文以飞播植被恢复技术为突破口,研究沙埋和土壤水分对种子萌发,幼苗出土和生长的影响,探讨幼苗出土和生长对沙生环境的适应对策。对采用合适的物种进行生态工程建设,提高生态工程的稳定性及可持续性具有重要意义。同时,本项研究有助于加深半干旱区植物对沙生环境适应机理的认识。 以上述4种植物为研究对象,设定7个沙埋深度和9个水分梯度,研究种子萌发和幼苗出土对沙埋和单次供水的响应。设定7个沙埋深度,选择3个沙丘部位,研究沙丘不同部位对植物种子萌发的影响。设定6个沙埋深度、4个水分梯度,研究两种蒿属植物幼苗生长对不同沙埋和供水的响应。得出如下主要结论: (1) 对于种子质量相对较大的柠条和羊柴而言,在一次性10-20 mm供水量条件下,幼苗主要在0.5-2 cm埋藏深度之间出土,但在埋藏深度为5 cm时这两个物种仍有少部分幼苗能够出土;对于种子质量相对较轻的油蒿和籽蒿而言,在一次性10-20 mm供水量时,幼苗主要在0.5 cm埋藏深度出土,油蒿和籽蒿幼苗在埋藏深度为1.5和2 cm时不能出苗。沙埋深度为0.5 cm时,4个物种出苗率较高、出苗时间较短、出苗速率较快。 (2) 实验期内(30天)在一次性供水量分别为5、7.5和7.5mm时,柠条、羊柴和油蒿出土幼苗全部死亡;在一次性供水量高于15-20 mm时,出土幼苗死亡率低于50%;籽蒿在供水量高于10 mm时出土幼苗死亡率低于50%;随供水量的增加4个物种出土幼苗的死亡率降低。 (3) 结合毛乌素沙地降雨特点与本文实验结果,0.5 cm的沙埋及7.5 mm以上的单次降雨量是上述4种植物自然条件下出苗较高的重要条件。 (4) 在沙丘顶部,2-7 cm沙埋深度之内各个物种不同沙埋深度的种子萌发率差异不显著。沙丘背风坡中部和底部,4个物种在沙埋深度为1 cm时的种子萌发率均显著高于5、7 cm时的萌发率。当沙埋深度为1-5 cm时,柠条和羊柴种子在坡面不同位置的萌发率均高于20%,且显著高于7 cm沙埋深度时的萌发率。在背风坡底部时,柠条、羊柴、油蒿和籽蒿的种子萌发率达到最大值,分别为45.2±3.27%、48.4±5.21%、20.8±4.63%和22.4±4.83%。4个物种的种子萌发率从沙丘顶部到背风坡中部到底部呈递增趋势,表明背风坡中部和底部的环境条件要比顶部更适合种子萌 发。 (5) 部分沙埋促进幼苗生长。2种蒿属植物幼苗在沙埋深度为0.25、0.5 H时比在0、0.75 H时具有更高的生物量、叶面积、相对生长速率(RGR)和净同化速率(NAR)。在75 mm/月供水量时,油蒿幼苗具有较高的生物量和叶面积,但当供水量达到100 mm/月时其幼苗生长受到抑制。油蒿幼苗在遭遇较深(0.5、0.75 H)沙埋时的根冠比要显著高于未沙埋幼苗的根冠比;籽蒿幼苗根冠比在不同沙埋条件下没有显著变化。籽蒿幼苗在50 mm供水量时具有较高的RGR。油蒿幼苗在75 mm供水量时具有较高的RGR和NAR。
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Top-illuminated metamorphic InGaAs p-i-n photodetectors (PDs) with 50% cut-off wavelength of 1.75 mu m at room temperature are fabricated on GaAs substrates. The PDs are grown by a solid-source molecular beam epitaxy system. The large lattice mismatch strain is accommodated by growth of a linearly graded buffer layer to create a high quality virtual InP substrate indium content in the metamorphic buffer layer linearly changes from 2% to 60%. The dark current densities are typically 5 x 10(-6) A/cm(2) at 0 V bias and 2.24 x 10(-4) A/cm(2) at a reverse bias of 5 V. At a wavelength of 1.55 mu m, the PDs have an optical responsivity of 0.48 A/W, a linear photoresponse up to 5 mW optical power at -4 V bias. The measured -3 dB bandwidth of a 32 mu m diameter device is 7 GHz. This work proves that InGaAs buffer layers grown by solid source MBE are promising candidates for GaAs-based long wavelength devices.
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本文系统研究了沈阳城市森林的布局与结构、城市森林功能、城市森林病虫害发生与树木健康状况和城市自然资源与社会经济状况等指标对沈阳城市森林生态系统健康与管理的影响。同时一,采用2种生态系统健康评价方法对沈阳城市森林生态系统健康状况进行了评价,并提出了沈阳城市森林生态系统健康管理的对策。研究结果如下:1、截至2004年末,沈阳城市森林植被覆盖率已经达到35%,城市森林林地分布基本合理,但需要进一步加强道路林地、居住区林地和城郊大面积生态林建设。2、沈阳城市森林以乔木为主,乔灌株数比为1.7:1,乔灌的覆盖度比约为7:1。3、沈阳城市森林不同类型林地中植物组成不同。公园林地中有74个属,137个种(变种);庭院林地中有53个属,104个种(变种);居住区林地中有45个属,81个种(变种);道路林地中有43个属,94个种(变种);运河风景林地中有75个属,142个种(变种);棋盘山风景林地中有48个属,118个种(变种)。4、公园林地、庭院林地、居住区林地、道路林地和运河风景林地的Shannon一Wiener多样性指数分别为2.78、3.05、3.15、3.18和3.18,均匀度指数分别为0.56、0.66、0.72、0.70和0.64。除了棋盘山风景林地外,沈阳城市森林中栽植总量超过乔木总量5%的乔木树种有7个属,分别为李、柳树、杨树、桧柏、榆树、槐树和银杏,7种树木总量达到了全部乔木总量的82.09%;栽植总量超过灌木总量5%的灌木树种也有7个属,分别为水腊、丁香、李属,小聚、玫瑰、忍冬和连翘,7个属灌木总量达到了全部灌木总量的87.92%。5、公园林地、庭院林地、道路林地和防护林地中OBH<20cm、20cm<DBH<60cm和DBH>60cm树木的比例分别为:57.9%、40.0%、2.1%,49.2%、47.8%、3.0%,65.3%、33.1%、1.6%和64.6%、34.9%、0.5%,表明沈阳城市森林树木的规格总体上偏小。6、经样方调查和CITYgreen模型计算,沈阳城市森林的生态效益约2.0亿USD/yr.。公园林地、庭院林地和风景林地的景观指标相对较高;道路林地和居住区林地的景观效果一般;防护林地的景观效果较差。7、目前已经发现的沈阳城市森林病害约600余种,虫害约700余种,其中杨树主要病虫害39种,柳树的主要病虫害有33种,榆树和槐树的主要病虫害均为,1种。杨柳树腐烂病、光肩星天牛、天幕毛虫、桃红颈天牛和美国白蛾等是近10年来沈阳城市森林中普遍发生和造成严重危害的主要病虫害。沈阳城市森林主要树木的平均健康指数为2.68,处于一般健康状态。8、沈阳城市森林的土壤和水资源状况均不利于树木的健康生长,沈阳的社会经济发展也有待于进一步提高。9、经过生物指示物法(光肩星天牛为生物指示物)、专家权重法、公众问卷调查和对比研究,沈阳城市森林生态系统总体上处于亚健康状态。10、通过对沈阳城市森林资源、管理状况的调查研究和健康状况的评价,本文提出了沈阳城市森林生态系统健康管理的对策,包括合理规划沈阳城市森林林地布局,增加道路林地、居住区林地和城郊林地的面积和植被覆盖率;调整树木种类组成,避免单一或少数树种的大量栽植,提高生物多样性水平;保护大树和古树;增加城市森林管理资金的投入;应用先进技术,采取科学的病虫害防治和植物养护方法,促进树木的健康生长等。This project systematically studied the urban forest ecosystem health and management in Shenyang. The study explored factors, such as urban forest structure, distribution, pests, aesthetic value, ecological benefit, natural resources and socieo-economic status, that affecting the urban forest ecosystem health and management. Two methods were used to evaluate the ecosystem health. This project also proposed Shenyang's urban forest ecosystem health management strategies. The research results can be summarized as follows: 1. As of the end of 2004, urban forest coverage in Shenyang is about 35%, and is in relatively even patch distribution pattern. However, the street trees and roadside forest patches, residential block forest patches should be enhanced. 2. Trees are the major component of the Shenyang s urban forest, followed by shrubs. The quantity ratio of tree to shrub is about 1.7:1, and the coverage ratio of trees to shrub is about 7:1. 3. Species composition varies by location. There are 74 genera, 137 species (including varieties) in the public parks; 53 genera, 104 species (and var.) in the green spaces of the institution (including school), factory, and company; 45 genera, 81 species (var.) in residential blocks; 43 genera, 94 species (var.) in streets and roadside forest patches; 75 genera, 142 species (var.) in the Canal landscape forest patches; 48 genera, 118 species (var.) in the Qipan Mountain recreation forest. 4. The Shannon-Woener indices varies in parks, in institution, factory, and company yards, in streets and roadside forest patches, in residential blocks.there are 2.78, 3.05, 3.18, 3.15, 3.18, respectively; and the evenness indices are 0.56, 0.66, 0.70, 0.72, 0.64, respectively. Besides the Qipan Mountain forest patches, trees of 7 genera, Prunus spp., Salix spp., Populus spp., Sabina spp., Ulmus spp., Robinia spp. and Ginkgo biloba are of more than 5% the total urban trees, respectively. In fact, trees from these 7 genera are about 82% of all trees in Shenyang's urban forests. In terms of shrubs, species of 7 genera, Ligustrum spp., Syringa spp., Prunus spp., Berberis spp., Rosa spp., Lonicera spp., and Forsythia spp. are more than 5% the total urban shrubs, respectively. 88% of all the shrubs in Shenyang s urban forest are from these 7 genera. 5. The diameter class of DBH<20cm, 20cm