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Assessing citizen science opportunities in forest monitoring using probabilistic topic modelling

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Forestry Studies in China 2014年第2期16卷 93-104页

作者： stefan Daume Matthias Albert klaus von Gadow Faculty of Forest Sciences and Forest Ecology Georg-August-University GttingenBüsgenweg 537077 GttingenGermany Department of Biodiversity Informatics Swedish Museum of Natural HistoryBox 5000710405 StockholmSweden Northwest German Forest Research Institute Grtzelstraβe 237079 GttingenGermany

Background： With mounting global environmental, social and economic pressures the resilience and stability of forests and thus the provisioning of vital ecosystem services is increasingly threatened. Intensified monitoring can help to detect ecological threats and changes earlier, but monitoring resources are limited. Participatory forest monitoring with the help of ＂citizen scientists＂ can provide additional resources for forest monitoring and at the same time help to communicate with stakeholders and the general public. Examples for citizen science projects in the forestry domain can be found but a solid, applicable larger framework to utilise public participation in the area of forest monitoring seems to be lacking. We propose that a better understanding of shared and related topics in citizen science and forest monitoring might be a first step towards such a framework. Methods： We conduct a systematic meta-analysis of 1015 publication abstracts addressing ＂forest monitoring＂ and ＂citizen science＂ in order to explore the combined topical landscape of these subjects. We employ ＇topic modelling an unsupervised probabilistic machine learning method, to identify latent shared topics in the analysed publications. Results： We find that large shared topics exist, but that these are primarily topics that would be expected in scientific publications in general. Common domain-specific topics are under-represented and indicate a topical separation of the two document sets on ＂forest monitoring＂ and ＂citizen science＂ and thus the represented domains. While topic modelling as a method proves to be a scalable and useful analytical tool, we propose that our approach could deliver even more useful data if a larger document set and full-text publications would be available for analysis. Conclusions： We propose that these results, together with the observation of non-shared but related topics, point at under-utilised opportunities for public participation in forest monitoring.

关键词： Forest monitoring Citizen science Participatory forest monitoring Probabilistic topic modelling Text analysis

Relationship of Isokinetic Leg Press Force with Jumping Performance and 1RM in the Squat

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Journal of Science in Sport and Exercise 2022年第2期4卷 180-187页

作者： Sebastian Möck stefan Erlewein Christoph Mickel klaus Wirth Department of Exercise Science Olympic Training and Testing Center of HessenOtto-Fleck-Schneise 460528 Frankfurt am MainGermany Institute of Applied Training Science LeipzigGermany Athlyzer GmbH Frankfurt am MainGermany Sport and Exercise Sciences University of Applied Sciences Wiener NeustadtWiener NeustadtAustria

Purpose Muscle strength and power are important requirements in many *** correlation of jumping performance as manifestation of muscle power and squatting one-repetition maximum(1RM)has been shown in several *** with maximum force in a linear isokinetic leg press are still *** different testing devices produce different relationships and rotational isokinetic measurements show conflicting results,further evidence is *** We investigated the correlation of isokinetic leg press force at 0.1 m/s and 0.7 m/s with squat 1RM and jumping performance in different vertical *** The results show medium to strong,significant correlations for isokinetic force at 0.1 m/s with squat-and counter-movement-jump performance,whereas isokinetic force at 0.7 m/s showed strong,significant correlations for both jumping *** jump performance(dropping heights:20,30,40,and 50 cm,respectively)reveals weak to medium,significant correlations with isokinetic force at 0.1 m/s and weak,significant correlations with isokinetic force at 0.7 m/*** 1RM displays strong relationships to isokinetic force with greater coefficients regarding higher movement speed in the isokinetic *** The maximum strength of the leg extensors displays a basic requirement for vertical jumping with great motion in knee-and hip-joints and should be considered in training *** vertical jumps that are mainly generated via ankle motion,maximum strength of knee-and hip-extensors plays an indirect role to guarantee for performance-enhancing ***,in strength testing,different manifestations of strength performance should carefully be taken into account.

关键词： Isokinetics Diagnostics Performance Resistance Training

Regulatory and Functional Aspects of Indolic Metabolism in Plant Systemic Acquired Resistance

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Molecular Plant 2016年第5期9卷 662-681页

作者： Elia Stahl Patricia Bellwon stefan Huber klaus Schlaeppi Friederike Bernsdorff Armelle Vallat-Michel Felix Mauch Jurgen Zeier Department of Biology Heinrich Heine University Dusseidorf Universiyatsstraβ 1 40225 Dusseidorf Germany Plant Biology Section University of Fribourg Route Albert Gockel 3 1700 Fribourg Switzerland Institut de Chimie Unlversite de Neuchatel Avenue Bellevaux 51 2007 Neuchatel Swttzerland Cluster of Excellence on Plant Sciences (CEPLAS) Heinrich Heine University Dusseldorf Universitatsstraβe 1 D-40225 Dusseldorf Germany Agroscope Institute for Sustainability Sciences Reckenholzstrasse 191 CH-8046 Zurich Switzerland

Tryptophan-derived, indolic metabolites possess diverse functions in Arabidopsis innate immunity to microbial pathogen infection. Hers, we investigate the functional role and regulatory characteristics of indolic metabolism in Arabidopsis systemic acquired resistance （SAR） triggered by the bacterial pathogen Pseudomonas syringae. Indolic metabolism is broadly activated in both P. syringae-inoculated and distant, non-inoculated leaves. At inoculation sites, camalexin, indol-3-ylmethylamine （13A）, and indole-3-carboxylic acid （ICA） are the major accumulating compounds. Camalexin accumulation is positively affected by MYB122, and the cytochrome P450 genes CYP81F1 and CYP81F2. Local 13A production, by contrast, occurs via indole glucosinolate breakdown by PEN2- dependent and independent pathways. Moreover, exogenous application of the defense hormone salicylic acid stimulates 13A generation at the expense of its precursor indol-3-ylmethylglucosinolate （13M）, and the SAR regulator pipecolic acid primes plants for enhanced P. syringae-induced activation of distinct branches of indolic metabolism. In uninfected systemic tissue, the metabolic response is more specific and associated with enhanced levels of the indolics 13A, ICA, and indole-3-carbaldehyde （ICC）. Systemic indole accumulation fully depends on functional CYP79B2/3, PEN2, and MYB34/51/122, and requires functional SAR signaling. Genetic analyses suggest that systemi- cally elevated indoles are dispensable for SAR and associated systemic increases of salicylic acid. However, soil-grown but not hydroponically -cultivated cyp79b2/3 and pen2 plants, both defective in indolic secondary metabolism, exhibit pre-induced immunity, which abrogates their intrinsic ability to induce SAR.

关键词： indolic metabolism systemic acquired resistance Pseudomonas syringae Arabidopsis thaliana

Competition effects in an afrotemperate forest

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Forestry Studies in China 2014年第3期16卷 119-133页

作者： Thomas Seifert stefan Seifert Armin Seydack Graham Durrheim klaus von Gadow Department of Forest and Wood Science Stellenbosch University Scientific Services(Knysna) South African National Parks

Background： Information about competition responses is mainly available for monospecific stands or mixed stands with a small number of species. Studies on complex multi-species and highly structured forest ecosystems are scarce. Accordingly, the objective of this study was to quantify competition effects and analyse competition responses in a species-diverse afrotemperate forest in South Africa, based on an observational study with mapped tree positions and long-term diameter increment records. Methods： The sensitivity to competition was analysed for individual species and involved the calculation of the slope of the linear relation between the value of a competition index （CI） and diameter growth as a measure of sensitivity. In a next step different competition indices were combined and tree diameters were grouped in three classes as surrogates for canopy status and ontogenetic stage. Results： Five competition indices were found to be effective in showing sensitivity to competition for a number of canopy and sub-canopy species. Significant linear regressions were fitted for 18 of a total of 25 species. Species reactions varied significantly in their sensitivity to the different CIs. The indices were classified as belonging to two groups, those that responded more to local crowding and those that are more sensitive to overtopping, which revealed species-specific sensitivities to both factors. The analysis based on diameter classes revealed that species clearly changed their sensitivity to crowding or overtopping depending on diameter. Canopy and sub-canopy species showed distinct differences in their reactions. Conclusions： The application of multiple CIs brought novel insights relating to the dynamics of afrotemperate forests. The response patterns to different competition indices that focus on crowding and overtopping are varied and tree diameter dependent, indicating that oversimplified assumptions are not warranted in the interpretation of Cl- growth relations.

关键词： Observational study Multi-species forest Distance dependent competition indices Simultaneous competitionindex approach Tree-tree interaction Ontogenetic effect

Transport in graphene nanostructures

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Frontiers of physics 2011年第3期6卷 271-293页

作者： Christoph Stampfer stefan Fringes Johannes Gfittinger Francoise Molitor Christian Yolk Bernat Terrds Jan Dauber Stephan Engels stefan Schnez Arnhild Jacobsen Susanne Droscher Thomas Ihn klaus Ensslin JARA-FIT and II. Institute of Physics B RWTH Aachen University 52074 Aachen and Peter Griinberg Institute （PCI-9） Forschungszentrum Jiilich 52425 Jiilich Germany Solid State Physics Laboratory ETH Zurich 8093 Zurich Switzerland

Graphene nanostructures are promising candidates for future nanoelectronics and solid-state quan- tum information technology. In this review we provide an overview of a number of electron transport experiments on etched graphene nanostructures. We briefly revisit the electronic properties and the transport characteristics of bulk, i.e., two-dimensional graphene. The fabrication techniques for making graphene nanostructures such as nanoribbons, single electron transistors and quantum dots, mainly based on a dry etching ＂paper-cutting＂ technique are discussed in detail. The limitations of the current fabrication technology are discussed when we outline the quantum transport properties of the nanostructured devices. In particular we focus here on transport through graphene nanoribbons and constrictions, single electron transistors as well as on graphene quantum dots including dou- ble quantum dots. These quasi-one-dimensional （nanoribbons） and quasi-zero-dimensional （quantum dots） graphene nanostructures show a clear route of how to overcome the gapless nature of graphene allowing the confinement of individual carriers and their control by lateral graphene gates and charge detectors. In particular, wo emphasize that graphene quantum dots and double quantum dots are very promising systems for spin-based solid state quantum computation, since they are believed to have exceptionally long spin coherence times due to weak spin-orbit coupling and weak hyperflne interaction in graphene.

关键词： graphene nanostructures electron transport quantum dots

Obesity and its influence on liver dysfunction,morbidity and mortality after liver resection

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Hepatobiliary Surgery and Nutrition 2023年第5期12卷 704-714,I0018页

作者： Stephanie Kampf Michael Sponder Fabian Fitschek Daniel Laxar Martin Bodingbauer Carina Binder stefan Stremitzer klaus Kaczirek Christoph Schwarz Division of Visceral Surgery Department of General SurgeryMedical University of ViennaViennaAustria Division of Cardiology Department of Internal Medicine IIMedical University of ViennaViennaAustria Clinical Institute of Pathology Medical University of ViennaViennaAustria

Background:Obesity and associated steatosis is an increasing health problem *** influence on post-hepatectomy liver failure(PHLF)and after liver resection(LR)is still ***:Patients who underwent LR were investigated and divided into three groups[normal weight:body mass index(BMI)18.5-24.9 kg/m2,overweight:BMI 25.0-29.9 kg/m2,obese:BMI≥30 kg/m2]in this retrospective *** aim of this study was to assess the influence of BMI and nonalcoholic steatohepatitis(NASH)on PHLF and ***:Of 888 included patients,361(40.7%)had normal weight,360(40.5%)were overweight,167(18.8%)were *** age was 62.5 years(IQR,54-69 years).The primary indication for LR was colorectal liver metastases(CLM)(n=366,41.2%).NASH was present in 58(16.1%)of normal weight,84(23.3%)of overweight and 69(41.3%)of obese patients(P<0.001).PHLF occurred in 16.3%in normal weight,15.3%in overweight and 11.4%in obese patients(P=0.32).NASH was not associated with *** was no association between patients’weight and the occurrence of postoperative complications(P=0.45).At multivariable analysis,solely major LR[odds ratio(OR):2.7,95%confidence interval(CI):1.83-4.04;P<0.001]remained a significant predictor for ***:Postoperative complications and PHLF are comparable in normal weight,overweight and obese patients and LRs using modern techniques can be safely performed in these patients.

关键词： Obesity liver resection(LR) post-hepatectomy liver failure(PHLF) morbidity

Reactive Magnetron Sputtering of Sulfide Films-A New Approach for Large Area Deposition of Thin Film Solar Cells

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Reactive Magnetron Sputtering of Sulfide Films-A New Approac...

Liposarcoma of the breast arising in a malignant phyllodes tumor:A case report and review of the literature

第十五届国际光伏科学与工程大会

作者： stefan Seeger Thomas Unold klaus Ellmer Hahn-Meitner-lnstitut Solarenergieforschung Glienicker Str.100 14109 Berlin Germany

Reactive magnetron sputtering from metallic targets in an argon-hydrogen-sulfide atmosphere (Ar/HS) can be used to deposit high-quality active layers (absorbers, buffers) in thin film solar cells consisting of sulfidic compound semiconductors. The deposition parameters substrate temperature, sputtering pressure and excitation mode of the plasma have to be tailored to the specific compound semiconductor material. The ion assistance during the film growth has to be controlled in such a way as to promote the film growth at low temperatures without introducing crystallographic and electronic defects due to high energy particle bombardment of the film. Examples are given for the preparation of CuInS, WS (absorbers) and InS (buffer). The encouraging results show that in the near future a large-scale magnetron sputter deposition process for complete thin film solar cells is feasible.

关键词： Reactive Magnetron Sputtering Thin Film Solar Cells Ion Assisted Growth Large-Area Deposition

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World Journal of Clinical Oncology 2015年第5期6卷 174-178页

作者： Malgorzata Banys-Paluchowski Eike Burandt Alexander Quaas Waldemar Wilczak stefan Geist Guido Sauter Natalia Krawczyk klaus Pietzner Peter Paluchowski Department of Obstetrics and Gynecology Marienkrankenhaus Hamburg22087 HamburgGermany Department of Pathology University of Hamburg Department of Obstetrics and Gynecology Regio Klinikum Pinneberg25421 PinnebergGermany Department of Obstetrics and Gynecology University of Duesseldorf Department of Obstetrics and Gynecology University of Berlin-Charite

Liposarcoma of the breast is a very rare malignant tumor. It can clinically manifest as a palpable breast mass and mimic primary breast cancer. We report an unusual case of a 51-year-old female who presented with an asymptomatic right breast mass, which was histologically diagnosed as well differentiated liposarcoma arisen within malignant phyllodes tumor. The patient underwent breast conserving surgery, received no adjuvant treatment and is disease-free after 2 years. Radiological and histopathological features are presented and described in detail. Data from the literature are presented and therapy recommendations discussed.

关键词： Liposarcoma Soft tissue sarcoma Breast cancer Phyllodes tumor Rare malignancies

Co-delivery of rhBMP-2 and zoledronic acid using calcium sulfate/hydroxyapatite carrier as a bioactive bone substitute to enhance and accelerate spinal fusion

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Bioactive Materials 2024年第6期36卷 256-271页

作者： Xinggui Tian Corina Vater Deepak Bushan Raina Lisa Findeisen Lucas-Maximilian Matuszewski Magnus Tägil Lars Lidgren Anja Winkler Robert Gottwald Niels Modler klaus-Dieter Schaser Alexander C.Disch stefan Zwingenberger University Center of Orthopaedic Trauma and Plastic SurgeryUniversity Hospital Carl Gustav Carus at TUD Dresden University of Technology01307DresdenGermany Center for Translational Bone Joint and Soft Tissue ResearchUniversity Hospital Carl Gustav Carus at TUD Dresden University of Technology01307DresdenGermany Lund University Faculty of MedicineDepartment of Clinical Sciences LundOrthopaedicsLund22185Sweden Institute of Lightweight Engineering and Polymer Technology at TUD Dresden University of Technology 01062DresdenGermany

Recombinant human bone morphogenetic protein-2(rhBMP-2)has been FDA-approved for lumbar fusion,but supraphysiologic initial burst release due to suboptimal carrier and late excess bone resorption caused by osteoclast activation have limited its clinical *** strategy to mitigate the pro-osteoclast side effect of rhBMP-2 is to give systemic bisphosphonates,but it presents challenges with systemic side effects and low local *** aim of this in vivo study was to analyze if posterolateral spinal fusion(PLF)could be improved by utilizing a calcium sulfate/hydroxyapatite(CaS/HA)carrier co-delivering rhBMP-2 and zoledronic acid(ZA).Six groups were allocated(CaS/HA,CaS/HA+BMP-2,CaS/HA+systemic ZA,CaS/HA+local ZA,CaS/HA+BMP-2+systemic ZA,and CaS/HA+BMP-2+local ZA).10-week-old male Wistar rats,were randomly assigned to undergo L4-L5 PLF with implantation of group-dependent *** 3 and 6 weeks,the animals were euthanized for radiography,μCT,histological staining,or biomechanical testing to evaluate spinal *** results demonstrated that the CaS/HA biomaterial alone or in combination with local or systemic ZA didn’t support ***,the delivery of rhBMP-2 significantly promoted *** systemic ZA with rhBMP-2 didn’t enhance spinal ***,the co-delivery of rhBMP-2 and ZA using the CaS/HA carrier significantly enhanced and accelerated PLF,without inhibiting systemic bone turnover,and potentially reduced the dose of ***,the treatment regimen of CaS/HA biomaterial co-delivering rhBMP-2 and ZA could potentially be a safe and cost-effective off-the-shelf bioactive bone substitute to enhance spinal fusion.

关键词： Calcium sulfate/hydroxyapatite Bone morphogenetic protein 2 Bisphosphonate Spinal fusion Bone substitute