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Science China(Technological Sciences) 2009年第11期52卷 3335-3347页

作者： KRONVANG Brian WINDOLF JФrgen GRANT Ruth andersen hans e THODSeN hans OVeSeN Niels B LARSeN SФren e National environmental Research Institute Aarhus University VejlsФvej 25 DK-8600 Silkeborg Denmark

Nationwide monitoring of the aquatic environment was initiated in 1988 in Denmark as a means to follow the outcome of the Action Plans for nutrient pollution of the aquatic environment. Five Action Plans have been adopted by the Danish Parliament since 1985 and the nationwide monitoring programme can be used to quantify the outcome as shown by reductions in nutrient discharges from both point and non-point sources. Moreover, the empirical experience gathered from nearly 20 years of monitoring is assisting the development and calibration of models for simulation of nitrogen leaching, nitrogen removal in groundwater and surface waters and the establishment of a P-index all covering the entire land area of Denmark.

关键词： nitrogen phosphorus monitoring data point sources non-point sources models Action Plans Danish experience

Air traffic monitoring using optimized ADS-B CubeSat constellation

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Astrodynamics 2024年第1期8卷 189-208页

作者： Ghulam Jaffer Rameez AMalik elias Aboutanios Nazish Rubab Ronnie Nader hans U.eichelberger Guy A.e.Vandenbosch Interdisciplinary Centre for Security Reliability and Trust(SnT)University of LuxembourgLuxembourg1855Luxembourg

The primary technique used for air traffic surveillance is ***,nowadays,its role in surveillance is gradually being replaced by the recently adopted Automatic Dependent Surveillance-Broadcast(ADS-B).ADS-B offers a higher accuracy,lower power consumption,and longer range than radar,thus providing more safety to *** coverage of terrestrial radar and ADS-B is confined to continental parts of the globe,leaving oceans and poles uncovered by real-time surveillance *** study presents an optimized Low-earth Orbit(LeO)-based ADS-B constellation for global air traffic surveillance over intercontinental trans-oceanic flight *** optimization algorithm is based on performance evaluation parameters,i.e.,coverage time,satellite availability,and orbit stability(precession and perigee rotation),and communication *** results indicate that the constellation provides ample coverage in the simulated global oceanic *** constellation is a feasible and cost-effective solution for global air supervision,which can supplement terrestrial ADS-B and radar systems.

关键词： constellation automatic dependent surveillance-broadcast (ADS-B) air traffic surveillance precession perigee rotation.

Pelleting and particle size reduction of corn increase net energy and digestibility of fiber,protein,and fat in corn-soybean meal diets fed to group-housed pigs

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1751-1760页

作者： Su A Lee Diego A.Rodriguez Chad B.Paulk hans H.Stein Department of Animal Sciences University of IllinoisUrbanaIL 61801USA Department of Grain Sciences and Industry Kansas State UniversityManhattanKS 66506USA

Background Reduction of the particle size of corn increases energy digestibility and concentrations of digestible and metabolizable *** may also reduce particle size of grain,but it is not known if there are interactions between particle size reduction and *** objective of this experiment was to test the hypothesis that particle size reduction and pelleting,separately or in combination,increase N balance,apparent total tract digestibility(ATTD)of fiber and fat,and net energy(Ne)in corn-soybean meal diets fed to group-housed *** Six corn-soybean meal-based diets were used in a 3×2 factorial design with 3 particle sizes of corn(i.e.,700,500,or 300μm)and 2 diet forms(i.e.,meal or pelleted).Pigs were allowed ad libitum access to feed and ***-four castrated male pigs(initial weight:29.52 kg;standard diviation:1.40)were allotted to the 6 diets using a 6×6 Latin square design with 6 calorimeter chambers(i.e.,4 pigs/chamber)and 6 *** consumption and CO_(2)and CH_(4)productions were measured during fed and fasting states and fecal and urine samples were *** Regardless of particle size of corn,the ATTD of gross energy(Ge),N,and acid-hydrolyzed ether extract(Aee),and the concentration of Ne were greater(Pelleted diets than in meal *** of diet form,the ATTD of Ge,N,and Aee,and the concentration of Ne were increased(linear;Peducing the particle size of corn,but the increase was greater in meal diets than in pelleted diets(interaction;Pelleting and reduction of corn particle size increased nutrient digestibility and Ne,but increases were greater in meal diets than in pelleted diets.

关键词： Corn Digestibility Feed technology Net energy Particle size Pelleting

Bound State Description of Particles from a Quantum Field Theory of Fermions and Bosons, Compatible with Relativity

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Journal of High energy Physics, Gravitation and Cosmology 2024年第2期10卷 562-573页

作者： hans-Peter Morsch HOFF J&uumllich Germany

Both, the dilemma to find a quantum field theory consistent with einstein’s law of relativity and the problem to describe existing particles as bound states of matter has been solved by calculating bound state matrix elements from a dual fermion-boson Lagrangian. In this formalism, the fermion binding energies are compensated by boson energies, indicating that particles can be generated out of the vacuum. This yields quantitative solutions for various mesons ω (0.78 GeV) - Υ (9.46 GeV) and all leptons e, μ and τ, with uncertainties in the extracted properties of less than 1‰. For transparency, a Web-page with the address htpps://*** has been constructed, where all calculations can be run on line and also the underlying fortran source code can be inspected.

关键词： Quantum Field Theory of Fermion and Boson Fields Hadrons and Leptons Described as Bound States of Relativistic Fermions and Bosons Leading to a Total energy equal to Zero

Towards engineering a portable platform for laparoscopic pre-training in virtual reality with haptic feedback

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虚拟现实与智能硬件（中英文） 2024年第2期6卷 83-99页

作者： hans-Georg eNKLeR Wolfgang KUNeRT Stefan PFeFFeR Kai-Jonas BOCK Steffen AXT Jonas JOHANNINK Christoph ReICH Furtwangen University 78120 FurtwangenGermany University Hospital and Faculty of Medicine Tuebingen 72076 TuebingenGermany

Background Laparoscopic surgery is a surgical technique in which special instruments are inserted through small incision holes inside the *** some time,efforts have been made to improve surgical pre training through practical exercises on abstracted and reduced *** The authors strive for a portable,easy to use and cost-effective Virtual Reality-based(VR)laparoscopic pre-training platform and therefore address the question of how such a system has to be designed to achieve the quality of today's gold standard using real tissue *** VR controllers are limited regarding haptic *** haptic feedback is necessary or at least beneficial for laparoscopic surgery training,the platform to be developed consists of a newly designed prototype laparoscopic VR controller with haptic feedback,a commercially available head-mounted display,a VR environment for simulating a laparoscopic surgery,and a training *** To take full advantage of benefits such as repeatability and cost-effectiveness of VR-based training,the system shall not require a tissue sample for haptic *** is currently calculated and visually displayed to the user in the VR *** the prototype controller,a first axis was provided with perceptible feedback for test *** of the prototype VR controllers can be combined to simulate a typical both-handed use case,e.g.,laparoscopic suturing.A Unity based VR prototype allows the execution of simple standard *** The first prototype enables full operation of a virtual laparoscopic instrument in *** addition,the simulation can compute simple interaction *** challenges lie in a realistic real-time tissue simulation and calculation of forces for the haptic *** weaknesses were identified in the first hardware prototype,which will be improved in subsequent *** degrees of freedom of the controller are to be provided with haptic *** make forces t

关键词： Laparoscopic surgery Training Virtual reality Controller Haptic feedback Kinesthetic skills

Why ecosystem characteristics predicted from remotely sensed data are unbiased and biased at the same time-and how this affects applications

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Forest ecosystems 2024年第1期11卷 24-31页

作者： Goran Ståhl Terje Gobakken Svetlana Saarela Henrik J.Persson Magnus ekstrom Sean P.Healey Zhiqiang Yang Johan Holmgren eva Lindberg Kenneth Nystrom emanuele Papucci Patrik Ulvdal hans OleØrka erik Næsset Zhengyang Hou Håkan Olsson Ronald e.McRoberts Department of Forest Resource Management Swedish University of Agricultural Sciences90183UmeåSweden Faculty of environmental Sciences and Natural Resource Management Norwegian University of Life SciencesÅsNorway USDA Forest Service Rocky Mountain Research StationOgdenUTUSA The Key Laboratory for Silviculture and Conservation of Ministry of education Beijing Forestry UniversityBeijing100083China Department of Forest Resources University of MinnesotaSt.PaulMNUSA

Remotely sensed data are frequently used for predicting and mapping ecosystem characteristics,and spatially explicit wall-to-wall information is sometimes proposed as the best possible source of information for ***,wall-to-wall information typically relies on model-based prediction,and several features of model-based prediction should be understood before extensively relying on this type of *** such feature is that model-based predictors can be considered both unbiased and biased at the same time,which has important implications in several areas of *** this discussion paper,we first describe the conventional model-unbiasedness paradigm that underpins most prediction techniques using remotely sensed(or other)auxiliary *** this point of view,model-based predictors are typically ***,we show that for specific domains,identified based on their true values,the same model-based predictors can be considered biased,and sometimes severely *** suggest distinguishing between conventional model-bias,defined in the statistical literature as the difference between the expected value of a predictor and the expected value of the quantity being predicted,and design-bias of model-based estimators,defined as the difference between the expected value of a model-based estimator and the true value of the quantity being *** show that model-based estimators(or predictors)are typically design-biased,and that there is a trend in the design-bias from overestimating small true values to underestimating large true ***,we give examples of applications where this is important to acknowledge and to potentially make adjustments to correct for the design-bias *** argue that relying entirely on conventional model-unbiasedness may lead to mistakes in several areas of application that use predictions from remotely sensed data.

关键词： Bias Model-based inference Design-based inference

Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity

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Forest ecosystems 2024年第2期11卷 142-151页

作者： Teresa Valor Lluís Coll David I.Forrester hans Pretzsch Miren del Río Kamil Bielak Bogdan Brzeziecki Franz Binder Torben Hilmers Zuzana Sitková Roberto Tognetti Aitor Ameztegui Department of Agricultural and Forest Sciences and engineering(DCeFA) University of LleidaAv.Alcalde Rovira Roure 191E25198 LleidaSpain Joint Research Unit CTFC-AGROTeCNIO-CeRCA Ctra.Sant LlorençKm.225280SolsonaSpain Swiss Federal Institute of Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland CSIRO Land and Water GPO Box 1700CanberraACT2601Australia Chair of Forest Growth and Yield Science School of Life Sciences WeihenstephanTechnical University of MunichHans-Carl-Von-Carlowitz-Platz 285354FreisingGermany Forest Research Center INIA-CSICCtra.A Coruña Km 7.528040MadridSpain IuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIASpain Department of Silviculture Institute of Forest SciencesWarsaw University of Life SciencesNowoursynowska 159/3402776WarsawPoland Bavarian State Institute of Forestry(LWF) Hans-Carl-von-Carlowitz-Platz 1D-85354FreisingGermany National Forest Centre Forest Research InstituteT.G.Masaryka 2296001ZvolenSlovakia Faculty of Agricultural Environmental and Food SciencesFree University of Bozen-Bolzano Piazza Università1 I-39100Bolzano

Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerning the variation in competitive effect and response of different species along climatic gradients. In this study, we investigated the importance of climate, tree size, and competition on the growth of three tree species: spruce(Picea abies), fir(Abies alba), and beech(Fagus sylvatica), and examined their competitive response and effect along a climatic ***: We selected 39 plots distributed across the european mountains with records of the position and growth of 5,759 individuals. For each target species, models relating tree growth to tree size, climate and competition were proposed. Competition was modelled using a neighbourhood competition index that considered the effects of inter-and intraspecific competition on target trees. Competitive responses and effects were related to *** methods and information theory were used to select the best ***: Our findings revealed that competition had a greater impact on target species growth than tree size or climate. Climate did influence the competitive effects of neighbouring species, but it did not affect the target species? response to competition. The strength of competitive effects varied along the gradient, contingent on the identity of the interacting species. When the target species exhibited an intermediate competitive effect relative to neighbouring species, both higher inter-than intraspecific competitive effects and competition reduction occurred along the gradient. Notably, species competitive effects were most pronounced when the target species' growth was at its peak and weakest when growing conditions were far from their ***: Climate modulates the effects of competition from neighbouring trees on the target tree and not the susceptibility of th

关键词： Competition coefficient Competition reduction Interspecific competition Intraspecific competition Mixing effects Mixed species forest Neighbourhood models Plant-plant interactions

Diversity and connectedness of brine shrimp viruses in global hypersaline ecosystems

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Science China(Life Sciences) 2024年第1期67卷 188-203页

作者： Xuan Dong Cixiu Li Yiting Wang Tao Hu Fan Zhang Fanzeng Meng Meirong Gao Xuekai Han Guohao Wang Jiahao Qin hans Nauwynck edward CHolmes Patrick Sorgeloos Liying Sui Jie Huang Weifeng Shi State Key Laboratory of Mariculture Biobreeding and Sustainable Goods Yellow Sea Fisheries Research InstituteChinese Academy of Fishery SciencesLaboratory for Marine Fisheries Science and Food Production ProcessesLaoshan LaboratoryKey Laboratory of Maricultural Organism Disease ControlMinistry of Agriculture and Rural AffairsQingdao Key Laboratory of Mariculture Epidemiology and BiosecurityQingdao 266071China Shandong Provincial Hospital Affiliated to Shandong First Medical University Jinan 250021China Key Laboratory of emerging Infectious Diseases in Universities of Shandong Shandong First Medical University&Shandong Academy of Medical SciencesTaian 271000China Dalian Ocean University Dalian 116023China Asian Regional Artemia Reference Center Tianjin University of Science&TechnologyTianjin 300457China Ghent University Ghent 9000Belgium Sydney Institute for Infectious Diseases School of Medical SciencesThe University of SydneySydney 2006Australia Network of Aquaculture Centres in Asia-Pacific Bangkok 10900Thailand School of Public Health Shandong First Medical University&Shandong Academy of Medical SciencesJinan 250117China

Brine shrimp(Artemia)has existed on earth for 400 million years and has major ecological importance in hypersaline *** a crucial live food in aquaculture,brine shrimp cysts have become one of the most important aquatic products traded ***,our understanding of the biodiversity,prevalence and global connectedness of viruses in brine shrimp is still very limited.A total of 143 batches of brine shrimp(belonging to seven species)cysts were collected from six continents including 21 countries and more than 100 geographic locations worldwide during 1977–*** total,55 novel RNA viruses were identified,which could be assigned to 18 different viral families and related *** viruses were dsRNA viruses,16 were+ssRNA viruses,and 28 were−ssRNA *** analyses of the RNA-directed RNA polymerase(RdRp)showed that brine shrimp viruses were often grouped with viruses isolated from other invertebrates and ***,most brine shrimp viruses were related to those from different hosts that might feed on brine shrimp or share the same ecological niche.A notable case was the novel brine shrimp noda-like virus 3,which shared 79.25%(RdRp)and 63.88%(capsid proteins)amino acid identity with covert mortality nodavirus(CMNV)that may cause losses in *** addition,both virome composition and phylogenetic analyses revealed global connectedness in certain brine shrimp viruses,particularly among Asia and Northern *** highlights the incredible species diversity of viruses in these ancient species and provides essential data for the prevalence of RNA viruses in the global aquaculture *** broadly,these findings provide novel insights into the previously unrecognized RNA virosphere in hypersaline ecosystems worldwide and demonstrate that human activity might have driven the global connectedness of brine shrimp viruses.

关键词： brine shrimp Artemia virus diversity novel virus discovery global connectedness hypersaline ecosystem

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

X-ray polarimetry and its application to strong-field quantum electrodynamics

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High Power Laser Science and engineering 2023年第6期11卷 47-70页

作者： Qiqi Yu Dirui Xu Baifei Shen Thomas e.Cowan hans-Peter Schlenvoigt Shanghai Normal University ShanghaiChina Helmholtz-Zentrum Dresden-Rossendorf DresdenGermany State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina Technische Universität Dresden DresdenGermany

Polarimetry is a highly sensitive method to quantify changes of the polarization state of light when passing through matter and is therefore widely applied in material *** progress of synchrotron and X-ray free electron laser(XFeL)sources has led to significant developments of X-ray polarizers,opening perspectives for new applications of polarimetry to study source and beamline parameters as well as sample characteristics.X-ray polarimetry has shown to date a polarization purity of less than 1.4×10^(-11),enabling the detection of very small signals from ultrafast phenomena.A prominent application is the detection of vacuum *** birefringence is predicted in quantum electrodynamics and is expected to be probed by combining an XFeL with a petawatt-class optical *** review how source and optical elements affect X-ray polarimeters in general and which qualities are required for the detection of vacuum birefringence.

关键词： birefringence polarimetry polarizer quantum electrodynamics X-rays