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Thinning and in-stream wood recruitment in riparian second growth forests in coastal Oregon and the use of buffers and tree tipping as mitigation

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Journal of Forestry Research 2016年第4期27卷 821-836页

作者： Lee e.Benda S.e.Litschert Gordon Reeves robert Pabst TerrainWorks Mt. Shasta CA 96067 USA BLM National Operations Center Denver CO 80225-0047USA Pacific Northwest Research Station U.S. Forest ServiceCorvallis OR 97331 USA Oregon State University Corvallis OR 97331 USA

Many aquatic habitats in coastal Oregon have been impacted by historic land use practices that led to losses of in-stream wood and associated degraded fish habitats. Many of these streams are now bordered by stands of dense second growth forests（30–80 years） that are incorporated into riparian buffer zones with low wood recruitment and storage. Thinning in riparian zones is one management option to increase the rate of large tree growth and eventually larger in-stream wood, however, it raises concern about impacts on current wood recruitment, among other issues. Using a forest growth simulation model coupled to a model of in-stream wood recruitment, we explore riparian management alternatives in a Douglas-fir plantation in coastal Oregon. Alternatives included：（1） no treatment,（2） single and double entry thinning, without and with a 10-m buffer, and（3） thinning combined with mechanical introduction of some portion of the thinned trees into the stream（tree tipping）. Compared to no treatment, single and double entry thinning on one side of a channel, without a 10-m buffer, reduce cumulative instream wood volume by 33 and 42 %, respectively, after100 years（includes decay）. Maintaining a 10-m buffer reduces the in-stream wood loss to 7 %（single entry thin）and 11 %（double entry）. To completely offset the losses of in-stream wood in a single entry thin（on one or both sides of the stream）, in the absence or presence of a 10-m buffer,requires a 12–14 % rate of tree tipping. Relative to the notreatment alternative, cumulative in-stream wood storage can be increased up to 24 % in a double-entry thin with no buffer by tipping 15–20 % of the thinned trees（increased to 48 % if thinning and tipping simultaneously on both sides of the stream）. The predicted increases in in-stream wood that can occur during a thin with tree tipping may be effective for restoring fish habitat, particularly in aquatic systems that have poor habitat conditions and low levels of in-stream wood due to h

关键词： thinning mitigation coastal Oregon forests habitat piece plantation stands cumulative

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evaluation of the Living Conditions and Health Perceptions of Waste electrical and electronic equipment Handlers in the Informal Sector in Dakar

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Occupational Diseases and environmental Medicine 2024年第2期12卷 115-129页

作者： robert Faomowe Foko Awa Ndong Marius Kedote Fatoumata Bah Absa Lam Cheikh Diop Aminata Toure Mathilde Cabral Mamadou Fall Laboratoire de Toxicologie et d’ Hydrologie Facult&#233 de M&#233decine Pharmacie et Odontostomalogie Universit&#233 Cheikh Anta Diop de Dakar Dakar S&#233n&#233gal Unité Mixte de Recherche d&#8217Exploration et de Diagnostic Unit&#233 de Formation et de Recherche des Sciences de la Sant&#233 Universit&#233 Iba Der Thiam de Thi&#232s Thi&#232s S&#233n&#233gal Institut Ré gional de Sant&#233 Publique Universit&#233 d&#8217Abomey-Calavi Ouidah B&#233nin

electrical and electronic devices are becoming an increasingly important part of our society. In Africa, and in Senegal in particular, the handling and management of electronic and electrical equipment (eee) that has reached the end of its life is mainly informal. This professional environment is characterized by the disintegration of the sector and the social heterogeneity that can be found there. The objective of this study is to assess the standard of living of electrical and electronic equipment waste handlers in the Dakar region, as well as their perception of their health. A survey was used to obtain information on sociodemographic background, living arrangements, perception of health status, and good practices to be implemented in case of work-related health problems. Life style, perception of general health and health problems were ranged as excellent, very good, good, average and poor. Informal recyclers in the Dakar region lived mainly in rooms and buildings as tenants (49.1%), or in family homes (48.4%) before starting this activity, and 51.2% continue to live in rooms and buildings as tenants compared to 41.4% who still live in a family home. The perception of health status ranged from poor to excellent, and 4.9% believe that they are limited in work due to a disability or health problem. Informal work is a heterogeneous phenomenon that makes research and policymaking particularly complex. There are several external factors within informal Weee re-cyclers that can cause health problems or functional disability. However, the living conditions and the perception they have of their state of health are contradictory to the working conditions and the social environment to which they belong. A biomedical approach would consolidate these achievements by confirming or invalidating them.

关键词： e-Waste Informal Work Living Arrangements Health Perception Occupational exposure

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FORCeD SOLITARY WAVeS IN A PARAMeTRICALLY eXCITeD CIRCULAR TANK

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Science China Mathematics 1992年第5期35卷 570-575页

作者：王本仁 robert.e.APFeL Institute of Acoustics Nanjing University Nanjing 210008 PRC Yale University Connecticut 06520 U.S.A.

A new mode of nonpropagating solitary waves in circular tank, which are forcedly ex-cited in tbe vertical direction, is described. The waveform is measured and the data accordwell with the hyperbolic secant *** of the vibration modes of the wave showthat the mode is not a pure mode of circular container. A wax cone was inserted in themiddle of tank in order to keep down the plateau. The hysteresis phenomenon of excitation ofsolitary wave has been observed as well.

关键词： solitary wave water waves nonpropagating solitary wave parametrically excited vibration.

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Nanotechnology:fundamental research to product development

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engineering Sciences 2012年第5期10卷 42-44页

作者： Graham J Davie Zahra F Rad Carl Anthony Philip Prewett Jing Peng robert nordon The University of New South Wales Sydney NSW 2025 Australi The University of Birmingham Birmingham B15 2TT UK Harbin Institute of Technology Harbin 150001 China

The concept of an integrated "lab on a chip" has long been a goal for the micro-electro-mechanical-systems(MeMS) *** would entail the integration of not only the sampling and analysis of various functions,but also the ability to transmit this information off the chip to a central *** paper describes the initial steps in the fabrication of a "lab on a chip" which would continually analyze blood sampled via microneedles using techniques such as nano plasmonics,specifically,concentrations of *** analysis could then be transmitted off the chip using digital signal *** paper describes the analysis and optimization of the microneedle shape and size and the fabrication of the resulting needles in silicon using deep reactive ion etching(DRIe).The paper also describes the opportunities for fabrication of such needles in alternative materials and describes the issues that still have to be overcome before such an integrated device is realized.

关键词： MeMS micro-needles lab on a chip nanotechnology

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evolution of surgical skills training

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World Journal of Gastroenterology 2006年第20期12卷 3219-3224页

作者： Kurt e roberts robert L Bell Andrew J Duffy Department of Surgery Yale University School of Medicine 40 Temple StreetSuite 3ANew HavenCT 06510United Staets

Surgical training is changing： one hundred years of tradition is being challenged by legal and ethical concerns for patient safety, work hours restrictions, the cost of operating room time, and complications. Surgical simulation and skills training offers an opportunity to teach and practice advanced skills outside of the operating room environment before attempting them on living patients. Simulation training can be as straight forward as using real instruments and video equipment to manipulate simulated ＂tissue＂ in a box trainer. More advanced, virtual reality simulators are now available and ready for widespread use. early systems have demonstrated their effectiveness and discriminative ability. Newer systems enable the development of comprehensive curricula and full procedural simulations. The Accreditation Council of Graduate Medical education＇s （ACGMe） has mandated the development of novel methods of training and evaluation. Surgical organizations are calling for methods to ensure the maintenance of skills, advance surgical training, and to credential surgeons as technically competent. Simulators in their current form have been demonstrated to improve the operating room performance of surgical residents. Development of standardized training curricula remains an urgent and important agenda, particularly for minimal invasive surgery. An innovative and progressive approach, borrowing experiences from the field of aviation, can provide the foundation for the next century of surgical training, ensuring the quality of the product. As the technology develops, the way we practice will continue to evolve, to the benefit of physicians and patients.

关键词： Surgery Training Certification Skills Simulation Curriculum

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Controversies in the treatment of gastroesophageal reflux and achalasia

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World Journal of Gastroenterology 2006年第20期12卷 3155-3161页

作者： Kurt e roberts Andrew J Duffy robert L Bell Department of Surgery Yale University School of Medicine 40 Temple St. Suite 3 ANew HavenCT 06510United States

The immense success of laparoscopic surgery as an effective treatment of gastroesophageal reflux disease （GeRD） and achalasia has established minimal invasive surgery as the gold standard for these two conditions with lower morbidity and mortality, shorter hospital stay, faster convalescence, and less postoperative pain. One controversy in the treatment of GeRD evolves around laparoscopic antireflux surgery （LAP, S） as the preferred treatmerit for Barrett＇s esophagus and the procedure＇s potential to reduce the risk of adenocarcinoma of the esophagus. GeRD has also been associated with respiratory symptoms, asthma and laryngeal injury, and a second controversy prompts discussions about whether total or partial fundoplication is the more appropriate treatment for GeRD. A new and promising alternative in the treatment of GeRD is endoluminal therapy. Three types of this new treatment option will be discussed： radiofrequency energy delivered to the lower esophageal sphincter, the creation of a mechanical barrier at the gastroesophageal junction, and the direct endoscopic tightening of the lower esophageal sphincter. Laparoscopic surgery is discussed not only as a very effective treatment for GeRD but also as permanent cure for achalasia. This review analyzes the three most important treatment options for achalasia： medications, pneumatic dilatation, and surgical therapy. Medications as the only true non-invasive option in the treatment of achalasia are not as effective as LAPS because of their short half-life and variable absorption due to the poor esophageal emptying. The second treatment option, pneumatic dilatation, involves the stretching of the lower esophagus and is still considered the most effective nonsurgical treatment for achalasia. Finally, surgical therapy for achalasia and the two major controversies concerning this laparoscopic treatment are discussed. The first involves the extent to which the myotomy is extended onto the stomach, and the second concer

关键词： Gastroesophageal reflux disease Nissen Toupet Fundoplication Achalasia Heller myotomy

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Optimizing laser coupling,matter heating,and particle acceleration from solids using multiplexed ultraintense lasers

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Matter and Radiation at extremes 2024年第4期9卷 16-28页

作者： Weipeng Yao Motoaki Nakatsutsumi Sébastien Buffechoux Patrizio Antici Marco Borghesi Andrea Ciardi Sophia N.Chen emmanuel d’Humières Laurent Gremillet robert Heathcote Vojtech Horny Paul McKenna Mark N.Quinn Lorenzo Romagnani Ryan Royle Gianluca Sarri Yasuhiko Sentoku Hans-Peter Schlenvoigt Toma Toncian Olivier Tresca Laura Vassura Oswald Willi Julien Fuchs LULI-CNRS CEASorbonne UniversitéEcole PolytechniqueInstitut Polytechnique de ParisF-91128 Palaiseau CedexFrance Sorbonne Université Observatoire de ParisUniversité PSLCNRSLERMAF-75005 ParisFrance INRS-eMT 1650 BoulLionel-BouletVarennesQuebec J3X 1S2Canada Center for Plasma Physics School of Mathematics and PhysicsQueen’s University BelfastBelfast BT71NNUnited Kingdom “Horia Hulubei”National Institute for Physics and Nuclear engineering 30 Reactorului StreetRO-077125 Bucharest-MagureleRomania University of Bordeaux Centre Lasers Intenses et ApplicationsCNRSCEAUMR 5107F-33405 TalenceFrance CeA DAMDIFF-91297 ArpajonFrance Université Paris-Saclay CEALMCE91680 Bruyères-le-ChatelFrance Central Laser Facility STFC Rutherford Appleton LaboratoryDidcotUnited Kingdom SUPA Department of PhysicsUniversity of StrathclydeGlasgow G40NGUnited Kingdom Department of Physics University of NevadaRenoNevada 89557USA Institute of Laser engineering Osaka University2-6 YamadaokaSuitaOsaka 565-0871Japan Institut fur Laser und Plasmaphysik Heinrich Heine Universitat DusseldorfDusseldorfGermany

Realizing the full potential of ultrahigh-intensity lasers for particle and radiation generation will require multi-beam arrangements due to technology ***,we investigate how to optimize their coupling with solid ***,we show that overlapping two intense lasers in a mirror-like configuration onto a solid with a large preplasma can greatly improve the generation of hot electrons at the target front and ion acceleration at the target *** underlying mechanisms are analyzed through multidimensional particle-in-cell simulations,revealing that the self-induced magnetic fields driven by the two laser beams at the target front are susceptible to reconnection,which is one possible mechanism to boost electron *** addition,the resistive magnetic field generated during the transport of the hot electrons in the target bulk tends to improve their *** simulations also indicate that such effects can be further enhanced by overlapping more than two laser beams.

关键词： laser acceleration particle

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Developmental ecology of the American horseshoe crab Limulus polyphemus

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Current Zoology 2010年第5期56卷 550-562页

作者： Mark L.BOTTON Richard A.TANKeRSLeY robert e.LOVeLAND Department of Natural Sciences Fordham University Department of Biological Sciences Florida Institute of Technology Department of ecology Evolution and Natural Resources Rutgers University

During spawning events, horseshoe crab eggs are released from the female＇s oviducts, and fertilized by one or more males. eggs are shaped by the female into discrete clutches deposited in nests at depths of 10-20 cm on intertidal estuarine beaches. Distinguishing between fxesh eggs and the early developmental stages is obfuscated by the large amount of dense, opaque yolk. The first unambiguous confirmation of development is the formation of the rudimentary prosomatie appendages at the ＂limb bud＂ stage. Several days thereafter, the outer chorion is shed and the developing embryo expands and undergoes a series of molts within the clear inner egg membrane. The trilobite （first iustar） stage thus attained may remain within the beach sedi- ments for several more weeks, until hatching is facilitated by environmental factors such as hydration, agitation, and osmotic shock that accompany the infiltration of seawater into the nests. Trilobites exhibit endogenous eirgatidal swimming rhythms that are entrained by mechanical agitation, suggesting that peaks in larval swimming are timed to coincide with periods of high water and the inundation of the nests. Larval swimming is limited and does not appear to result in long-distance dispersal. The limited dispersal of the larvae has important implications for the population dynamics of relatively isolated populations. The rate of larval development is highly plastic and is influenced by temperature, salinity, dissolved oxygen, and the presence of pollutants. The broad environmental tolerances of horseshoe crab embryos and larvae are important in understanding their current geographic distribution and their evolutionary persistence

关键词： Horseshoe crab Limulus Development embryo Larval dispersal

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Relationship of minimum winter temperature and temperature seasonality to the northern range limit and species richness of trees in North America

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Journal of Geographical Sciences 2022年第2期32卷 280-290页

作者： Hong QIAN ZHANG Yangjian robert e.RICKLeFS Xianli WANG Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL 62703USA Key Laboratory of ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China Department of Biology University of Missouri–St.LouisSt.LouisMO 63121USA Northern Forestry Centre Canadian Forest ServiceNatural Resources Canada5320-122nd StreetEdmontonAB T6H 3S5Canada Department of Renewable Resources University of Alberta751 General Service Building EdmontonAB T6G 2H1Canada

Biologists have considered both winter coldness and temperature seasonality as major determinants of the northern limits of plants and animals in the Northern Hemisphere,which in turn drive the well-known latitudinal diversity ***,few studies have tested which of the two climate variables is the primary *** this study,we assess whether winter coldness or temperature seasonality is more strongly associated with the northern latitudinal limits of tree species and with tree species richness in North *** species were recorded in each of 1198 quadrats of 110 km×110 km in North *** used correlation and regression analyses to assess the relationship of the latitude of the northern boundary of each species,and of species richness per quadrat,with winter coldness and temperature *** richness was analyzed within 38 longitudinal,i.e.,north-south,bands(each being>1100 km long and 110 km wide).The latitudes of the northern range limits of tree species were three times better correlated with minimum temperatures at those latitudes than with temperature *** average,minimum temperature and temperature seasonality together explained 81.5%of the variation in the northern range limits of the tree species examined,and minimum temperature uniquely explained six-fold(33.7%versus 5.8%)more of this variation than did temperature *** of tree species richness with minimum temperatures were stronger than correlations with temperature seasonality for most of the longitudinal bands *** to temperature seasonality,winter coldness is more strongly associated with species distributions at high latitudes,and is likely a more important driver of the latitudinal diversity gradient.

关键词： cold tolerance latitudinal diversity gradient minimum temperature temperature seasonality temperature variation trees tropical conservatism hypothesis

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A Predictive,Two-Parameter Model for the Movement of Reservoir Landslides

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Journal of earth Science 2020年第6期31卷 1051-1057页

作者： robert e.Criss Wenmin Yao Changdong Li Huiming Tang Department of earth and Planetary Sciences Washington UniversitySt.Louis MO 63130USA Faculty of engineering China University of GeosciencesWuhan 430074China

Monitoring data show that many landslides in the Three Gorges region,China,undergo step-like displacements in response to the managed,quasi-sinusoidal annual variations in reservoir *** behavior is consistent with motion initiating when the reservoir water level falls below a critical level that is intrinsic to each landslide,with the subsequent displacement rate of the landslide being proportional to the water depth below that critical *** motion terminates when the water level rises back above the critical level,so the annual step size is the time integral of the instantaneous displacement *** responses are incorporated into a differential equation that is easily calibrated with monitoring data,allowing prediction of landslide movement from actual or anticipated reservoir level *** successes include(1)initiation and termination of the annual sliding steps at the critical reservoir level,producing a series of steps;(2)prediction of variable step size,year to year;and(3)approximate prediction of the shape and size of each annual *** rainfall correlates poorly with step size,probably because its effect on groundwater levels is dwarfed by the 30 m annual variations in the level of the Three Gorges *** landslide behavior is suggested.

关键词： reservoir landslide parsimonious model step-like displacement displacement prediction critical reservoir level

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