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Clearcuts and related secondary dieback undermine the ecological effectiveness of fSC certification in a boreal forest

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Ecological Processes 2020年第1期9卷 108-116页

作者： Jeanette Silvin Blumröder Monika T.hoffmann Olga Ilina Susanne Winter Peter R.Hobson Pierre L.Ibisch Centre for Econics and Ecosystem Management Eberswalde University for Sustainable DevelopmentAlfred-Moeller-Str.116225 EberswaldeGermany Petrozavodsk State University Lenina st.33185000 PetrozavodskRussia Karelian Nature Conservancy(SPOK) PetrozavodskRussia WWf Germany Reinhardtstr1810117 BerlinGermany Centre for Econics and Ecosystem Management Writtle University CollegeLordship RoadWrittle Chelmsford Essex CM13RRUK

Background:Over the last 25 years,the prominent forest certification system established by the forest Stewardship Council(fSC)has used by many companies worldwide for claiming responsible forest *** objectives of the Russian National fSC standard to decrease the size of clearcuts and the retention of forest elements such as residual seed trees need on-site validation to proof the effectiveness of *** assess the ecological impacts of harvesting practices and benefits of fSC certification,we geospatially compared logging activities with and without fSC *** a sample area covering approximately 3,000 km^(2) in the east of the Russian Arkhangelsk Region,we used available data on tree cover loss and satellite images to assess secondary impacts of clearcuttings on adjacent remnant forests and to quantify the logging ***,the size and structure as well as the density of skidding trails of ten specific clearcuttings located within the sample area were surveyed using satellite images and in the field observation to delineate the boundaries of clearcuts and forested remnants within the ***:We found a significant increase of small-scale tree cover loss in the proximity of the *** dieback is possibly linked to the scale and intensity of logging in the *** the investigated clearcuts,fSC failed to reduce the size,to increase the retention of forest remnants including seed trees on logged areas,and to maintain larger tracts of undisturbed ground and soil compared to clearcuts that were logged before they received ***:Trees and forest remnants remaining inside an increasingly stressed forest ecosystem matrix may not resist further harvesting-related and climate change-induced stresses and ***-scale clearcuttings seem to have negative impacts even in adjacent forests and undermine the ecological effectiveness of fSC certification in the study *** Russi

关键词： Ecological effectiveness Impact assessment forest certification Sustainable forestry

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商业化家禽生产对全球家禽遗传资源的影响

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中国家禽 2010年第24期32卷 6-11页

作者： Irene hoffmann 世界粮农组织动物生产及卫生司意大利罗马00153

家禽的生物学特性和经济学特性(如繁殖率高、繁殖周期短、单位成本低、育种材料易于携带和运输以及经济节约型规模化养殖)使家禽业成为畜牧业中最先进的行业。在所有动物物种中,家禽的育种程度最高。所有牲畜品种中,家禽具有最高的饲料... 详细信息

家禽的生物学特性和经济学特性(如繁殖率高、繁殖周期短、单位成本低、育种材料易于携带和运输以及经济节约型规模化养殖)使家禽业成为畜牧业中最先进的行业。在所有动物物种中,家禽的育种程度最高。所有牲畜品种中,家禽具有最高的饲料转化率,且无论在发展中国家还是发达国家,禽肉的消费比率逐年增长。据世界粮农组织动物生产及卫生司预测,发展中国家禽肉消费年增长率将由目前的25%增加到2030年的34%。另一方面,家禽产业结构的快速调整已成为威胁家禽遗传资源的重要因素。目前,全世界已有30%的家禽品种濒临灭绝,9%的家禽品种已经灭绝。此外,遗传多样性丢失、消费涉及的动物福利以及环境问题也对家禽资源产生威胁。因此,家禽业是政府决策过程中权衡各种因素的理想案例,如食品安全与农业生物多样性、公共投资与私人投资、规模化养殖与小规模养殖、创造就业机会与自谋职业、标准和食品安全与食物多样性等。本文重点关注家禽遗传多样性、家禽育种、家禽研究的公共投资和私人投资以及食品安全等方面的问题。

关键词：家禽生产遗传资源遗传多样性育种

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Marijuana Use and Depressive Symptoms among Young People: Examining Unidirectional and Bidirectional Effects

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Health 2018年第8期10卷 1066-1078页

作者： John P. hoffmann Department of Sociology Brigham Young University Provo UT USA

Research suggests that the prevalence of marijuana use and depression are increasing in the United States. Although it is not entirely clear what accounts for these coincident trends, several studies have shown that these two health concerns are associated among young people. This study assessed four hypotheses regarding the association between marijuana use and depression: 1) whether marijuana use affects subsequent symptoms of depression;2) whether depressive symptoms affect subsequent marijuana use;3) whether they are associated in a bidirectional (reciprocal) manner;and 4) whether the association between the two is confounded by stressful life events. Using eight years of longitudinal data from the family Wellness and Health Study, a fixed-effects regression model provided empirical support for the first hypothesis only, but not for the others. future research should explore in greater detail why marijuana use may have a causal impact on experiences with depression among young people.

关键词： Marijuana Use Depressive Symptoms Young People

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Tracking of flat Belts

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Journal of Mechanics Engineering and Automation 2012年第1期2卷 27-36页

作者： Martin Egger Klaus hoffmann Mechanical Engineering FH-OOE Wels 4600 Austria Engineering Design and Logistics Engineering TU- Vienna Wien 1060 Austria

When applying fiat belts, correct tracking of the belt through the installation has to be assured. Since flat belts are commonly used for conveying and transmission purposes, tracking systems have been well developed, but the ultimate tracking behaviour of the belt can be greatly enhanced by taking special care in the creation of an adequate tracking mechanism. To obtain long-life operation and full value from the equipment, the correct tracking technique plays an important role. This paper deals with two tracking techniques： The skewed and the angled pulley axis. Numerical simulation results are compared with both measurements and an analytical approach. The advantages of numerical simulation compared to experimental tests are ease, convenience and the absence of any safety risk. Compared to analytical approaches the simulation is used for systems for which simple closed form analytic solutions are not possible.

关键词： flat belt belt tracking angled pulley axis skewed pulley axis.

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A Survey of Control Structures for Reconfigurable Petri Nets

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Journal of Computer and Communications 2015年第2期3卷 20-28页

作者： Julia Padberg Kathrin hoffmann Hamburg University of Applied Science Hamburg Germany

Software systems are increasingly executed in dynamic infrastructures. These infrastructures are dynamic as they are themselves subject to change as they support various applications that may or may not share some of the resources. Dynamic software systems become more and more important, but are difficult to handle. Modeling and simulating dynamic systems requires the representation of their processes and the system changes within one model. To that effect, reconfigurable Petri nets consist of a Petri net and a set of rules that can modify the Petri net. Their main feature is the capability to model complex coordination behavior in dynamically adapting infrastructures. The interplay of both levels of dynamic behavior requires a very precise description, so the specification when and which rules are to be applied plays a crucial role for the convenient use of reconfigurable nets. We differentiate several types of reconfigurable Petri nets and present a survey of control structure for these types, reconfigurable Petri nets. These control structures either concern the infrastructure, i.e., the rules and transformations or the system part, i.e., the firing behavior, or both. They are introduced by a short characterization and illustrated by examples. We state the results for various Petri net types and the tools supporting the different control structures.

关键词： Reconfigurable Petri Nets Net Transformation Control Structures Model Transformation Dynamic Software Systems

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Real-time whole-brain imaging of hemodynamics and oxygenation at micro-vessel resolution with ultrafast wide-field photoacoustic microscopy

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Light(Science & Applications) 2022年第6期11卷 1238-1252页

作者： Xiaoyi Zhu Qiang Huangl Anthony Dispirito Tri Vu Qiangzhou Rong Xiaorui Peng Huaxin Sheng Xiling Shen Qifa Zhou Laiming Jiang Ulrike hoffmann Junjie Yao Department of Biomedical Engineering Duke UniversityDurhamNC 27708USA Department of Pediatric Surgery Second Affiliated Hospital of Xi'an Jiaotong UniversityXi'anShaanxiChina Roski Eye Institute Department of OphthalmologyKeck School of MedicineUniversity of Southern CaliforniaLos AngelesCA 90033USA Department of Biomedical Engineering University of Southern CaliforniaLos AngelesCA 90089USA Department of Anesthesiology Duke UniversityDurhamNC 27708USA

High-speed high-resolution imaging of the whole-brain hemodynamics is critically important to facilitating neurovascular *** imaging speed and image quality are crucial to visualizing real-time hemodynamics in complex brain vascular networks,and tracking fast pathophysiological activities at the microvessel level,which will enable advances in current queries in neurovascular and brain metabolism research,including stroke,dementia,and acute brain ***,real-time imaging of oxygen saturation of hemoglobin(sO_(2))can capture fast-paced oxygen delivery dynamics,which is needed to solve pertinent questions in these fields and ***,we present a novel ultrafast functional photoacoustic microscopy(Uff-PAM)to image the whole-brain hemodynamics and ***-PAM takes advantage of several key engineering innovations,including stimulated Raman scattering(SRS)based dual-wavelength laser excitation,water-immersible 12-facet-polygon scanner,high-sensitivity ultrasound transducer,and deep-learning-based image upsampling.A volumetric imaging rate of 2 Hz has been achieved over a field of view(fOV)of 11×7.5×1.5 mm^(3) with a high spatial resolution of~10 μ*** the Uff-PAM system,we have demonstrated proof-of-concept studies on the mouse brains in response to systemic hypoxia,sodium nitroprusside,and *** observed the mouse brain's fast morphological and functional changes over the entire cortex,including vasoconstriction,vasodilation,and *** interestingly,for the first time,with the whole-brain fOV and micro-vessel resolution,we captured the vasoconstriction and hypoxia simultaneously in the spreading depolarization(SD)*** expect the new imaging technology will provide a great potential for fundamental brain research under various pathological and physiological conditions.

关键词： metabolism ultrafast resolution

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古北界在中国及其邻近国家的南部界线(英文)

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动物学报 2001年第2期47卷 121-131,T001页

作者： Robert S.hoffmann 国家自然历史博物馆

论述了一种客观地划分生物地理区域界线的方法。根据物种分布范围和系统发生或生态渊源关系等概念 ,在过去所提出的分界线附近选择一些地点 ,确定在这些地区中是否有某个物种分布 ,从而确定这些物种可能所隶属的生物地理区。依此方法 ,... 详细信息

论述了一种客观地划分生物地理区域界线的方法。根据物种分布范围和系统发生或生态渊源关系等概念 ,在过去所提出的分界线附近选择一些地点 ,确定在这些地区中是否有某个物种分布 ,从而确定这些物种可能所隶属的生物地理区。依此方法 ,作者在 4 6°N ,12 8°E和 2 4°N ,76°E之间选择了 12个地点 ,通过兽类的区系成份分析 ,并结合植被特征 ,探讨了中国及其邻近国家的古北界南界。结果表明 ,古北界和东洋界兽类区系成份在各地区的分布 (百分率 )分别如下 :东北部的吉林省 (10 0、0 )、东部的山东省 (90、10 )、江苏和安徽省 (59、4 1)、浙江 (54、4 6 ,沿海分别为 4 4、56 )、南部的海南岛 (19、81)、四川邛崃山 (87、13)、四川大雪山 (79、2 1)、云南云岭 (90、10 )、缅甸东北部 (52、4 8)、泰国 (7、93)、尼泊尔、锡金和不丹以及中国的喜马拉雅山南麓(4 5、55)和巴基斯坦 (6 3、37)。作者认为古北界和东洋界之间存在过渡区 ,过渡区东段在中国东部地区的中心约在 30°N ,南缘约在 2 8°N ,北缘约在 33°N ;中段山地的海拔高度在 150 0～ 2 50 0m之间 ,过渡区中心的海拔高度为 2 0 0 0m ;西段的印度河区作为东洋和古北两界的过渡区比作为东洋界向西的延伸更为合适。

关键词：古北界东洋界生物地理发展史渊源关系区域界线

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聚硅氯化铝(PASiC)混凝剂的特性及絮凝动态过程

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中国环境科学 2002年第3期22卷 227-230页

作者：岳钦艳高宝玉 H.H.Hahn E.hoffmann 山东大学环境科学与工程学院山东济南250100 InstituteofAquaticEnvironmentalEngineering

采用共聚与复合两种制备工艺,分别制备出具有不同碱化度(B)和不同Al/Si摩尔比系列的商用聚硅氯化铝(PASiC)混凝剂,并分别采用颗粒粒径测定方法和流动电流(SC)测定技术研究比较了PASiC和聚合氯化铝(PAC)混凝剂的颗粒大小、电动特性和凝... 详细信息

采用共聚与复合两种制备工艺,分别制备出具有不同碱化度(B)和不同Al/Si摩尔比系列的商用聚硅氯化铝(PASiC)混凝剂,并分别采用颗粒粒径测定方法和流动电流(SC)测定技术研究比较了PASiC和聚合氯化铝(PAC)混凝剂的颗粒大小、电动特性和凝聚絮凝动态过程.结果表明,Al/Si摩尔比、B值和制备工艺影响PASiC的聚合和带电特性.Al/Si摩尔比越小和B值越大,PASiC的颗粒就越大;在相同的B值下,PASiC较PAC具有更大的颗粒粒径.PASiC的电中和能力较PAC有所下降,且Al/Si摩尔比越小,PASiC的电中和能力下降越多;与PAC相比,PASiC具有更快的凝聚絮凝速度和形成更大的絮体;且Al/Si摩尔比越小,PASiC形成的絮体就越大.

关键词：聚硅氯化铝 PASiC 混凝剂特性絮凝动态过程颗粒大小流动电流

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超声波降解全氟辛烷磺酸和全氟辛酸的动力学

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化工学报 2011年第3期62卷 829-835页

作者：赵德明丁成徐新华 Michael R.hoffmann 浙江大学环境与资源学院浙江杭州310027 浙江工业大学化学工程与材料学院浙江杭州310032 W.M.Keck Laboratories California Institute of TechnologyPasadena

引言全氟辛烷磺酸基化合物和全氟辛酸化合物是一类重要的全氟化表面活性剂,也是其他许多全氟化合物的重要前体。自20世纪60年代电化学氟化反应方法应用于全氟辛烷磺酸（PfOS）和全氟辛酸（PfOA）等全氟化合物的生产以来,

关键词：全氟辛烷磺酸全氟辛酸超声波动力学

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The growth of Staphylococcus aureus and Escherichia coli in low-direct current electric fields

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International Journal of Oral Science 2014年第1期6卷 7-14页

作者： Dunya Zituni Heidi Schtt-Gerowitt Marion Kopp Martin Krnke Klaus Addicks Christian hoffmann Martin Hellmich franz faber Wilhelm Niedermeier Department of Prosthetic Dentistry School of Dental and Oral Medicine Cologne University Institute for Medical Microbiology Immunology and HygieneCologne University Institute for Anatomy I Cologne University Institute for Medical Statistics Informatics and Epidemiology Cologne University Department of Pre-Clinical Dentistry School of Dental and Oral Medicine Cologne University

Electrical potentials up to 800 mV can be observed between different metallic dental restorations. These potentials produce fields in the mouth that may interfere with microbial communities. The present study focuses on the impact of different electric field strengths （EfS） on the growth of Staphylococcus aureus （ATCC 25923） and Escherichia coil （ATCC 25922） in vitro. Cultures of S. aureus and E. coil in fluid and gel medium were exposed to different EfS. Effects were determined by calculation of viable counts and measurement of inhibition zones. In gel medium, anodic inhibition zones for S. aureuswere larger than those for E. coliat all field strength levels. In fluid medium, the maximum decrease in the viable count of S. aureus cells was at 10 V.m-1. field-treated S. aureus cells presented ruptured cell walls and disintegrated cytoplasm. Conclusively, S. aureus is more sensitive to increasing electric field strength than E. coll.

关键词： direct current Escherichia coli electrogaNanism gold electrode Staphylococcus aureus

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