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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

The vital threat of an upper gastrointestinal bleeding: Risk factor analysis of 121 consecutive patients

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World Journal of Gastroenterology 2006年第22期12卷 3597-3601页

作者： Peter Schemmer Frank Decker Genevieve Dei-Anane Volkmar Henschel klaus Buhl Christian Herfarth stefan Riedl Deptartment of General Surgery Ruprecht-Karls-University 69120 HeidelbergGermany Volkmar HenschelInstitute for Statistics and Medical BiometryRuprecht-Karls-University69120 HeidelbergGermany Institute for Statistics and Medical Biometry Ruprecht-Karls-University 69120 HeidelbergGermany Deptartment of General Surgery Ruprecht-Karls-University 69120 HeidelbergGermany

AIM： To analyze the importance in predicting patients risk of mortality due to upper gastrointestinal （UGI） bleeding under today＇s therapeutic regimen. METHODS： From 1998 to 2001, 121 patients with the diagnosis of UGI bleeding were treated in our hospital. Based on the patients＇ data, a retrospective multivariate data analysis with initially more than 270 single factors was performed. Subsequently, the following potential risk factors underwent a logistic regression analysis： age, gender, initial hemoglobin, coumarines, liver cirrhosis, prothrombin time （PT）, gastric ulcer （small curvature）, duodenal ulcer （bulbus back wall）, Forrest classification, vascular stump, variceal bleeding, MalloryWeiss syndrome, RBC substitution, recurrent bleeding, conservative and surgical therapy. RESULTS： Seventy male （58%） and 51 female （42%） patients with a median age of 70 （range： 21-96） years were treated. Their in-hospital mortality was 14%. While 12% （11/91） of the patients died after conservative therapy, 20% （6/30） died after undergoing surgical therapy. UGI bleeding occurred due to duodenal ulcer （n = 36; 30%）, gastric ulcer （n = 35; 29%）, esophageal varicosis （n = 12; 10%）, Mallory-Weiss syndrome （n = 8, 7%）, erosive lesions of the mucosa （n = 20; 17%）, cancer （n = 5; 4%）, coagulopathy （n = 4; 3%）, lymphoma （n = 2; 2%）, benign tumor （n = 2; 2%） and unknown reason （n = 1, 1%）. A logistic regression analysis of all aforementioned factors revealed that liver cirrhosis and duodenal ulcer （bulbus back wall） were associated risk factors for a fatal course after UGI bleeding. Prior to endoscopy, only liver cirrhosis was an assessable risk factor. Thereafter, liver cirrhosis, the location of a bleeding ulcer （bulbus back wall） andpatients＇ gender （male） were of prognostic importance for the clinical outcome （mortality） of patients with a bleeding ulcer.CONCLUSION： Most prognostic parameters used in clinical routine today are not reliable enough in predicting a patient＇s vital

关键词： UGT bleeding Mortality Risk factors

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

Identification of Early Nuclear Target Genes of Plastidial Redox Signals that Trigger the Long- Term Response of Arabidopsis to Light Quality Sh∽ts

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Molecular Plant 2015年第8期8卷 1237-1252页

作者： Lars Dietzel Christine Glaeer Monique Liebers stefan Hiekel Florence Courtois Olaf Czarneckit Hagen Schlicke Yan Zubo Thomas Borner klaus Mayer Bernhard Grimm Thomas Pfannschmidt Department of Plant Physiology Institute of General Botany and Plant Physiology Friedrich-Schiller-University of Jena Domburger Strasse 159 07743 JenaGermany MIPS/IBI Helmholtz Zentrum MGnchen German Research Center for Environmental Health (GmbH) Ingolst~dter Landstrasse 1 85764 Neuherberg Germany Institute of Biology/Plant Physiology Humboldt-University Berlin Philippstrasse 13 Building 12 10115 Berlin Germany Institute of Biology Genetics Humboldt-University Berlin Chausseestrasse 117 10115 Berlin Germany present address: Institut fer Molekulare Biowissenschaften Pflanzliche Zellphysiologie Max-von-Laue-Strasse 9 Biozentrum Goethe-Universit~t Frankfurt 60438Frankfurt am Main Germany Present address: Zentrum fur Molekulare Biologie an der Universitat zu Heidelberg (ZMBH) Im Neuenheimer Feld 282 69120 Heidelberg Germany present address: Universite Grenoble-Alpes F-38000 Grenoble France Present address: CNRS UMR5168 F-38054 Grenoble France present address: CEA iRTSV Laboratoire de Physiologie Cellulaire & Vgetale F-38054 Grenoble France Present address: INRA USC1359 F-38054 Grenoble France Present address: Plant Reproductive Biology Group Department of Physiology and Ceil-Biology Leibniz Institute of Rant Genetics and Crop Plant Research (IPK)OT Gatersleben Corrensstrasse 3 D-06466 Stadt Seeland Germany present address: KWS Saat AG Grimsehlstrasse 31 37555 Einbeck Germany present address: Dartmouth College Department of Biological Sciences Ufe Sciences Center 78 College Street Hanover NH 03755 USA

Natural illumination conditions are highly variable and because of their sessile life style, plants are forced to acclimate to them at the cellular and molecular level. Changes in light intensity or quality induce changes in the reduction/oxidation （redox） state of the photosynthetic electron chain that acts as a trigger for compen- satory acclimation responses comprising functional and structural adjustments of photosynthesis and metabolism. Such responses include redox-controlled changes in plant gene expression in the nucleus and organelles. Here we describe a strategy for the identification of early redox-regulated genes （ERGs） in the nucleus of the model organism Arabidopsis thaliana that respond significantly 30 or 60 min after the generation of a reduction signal in the photosynthetic electron transport chain. By comparing the response of wild-type plants with that of the acclimation mutant stn7, we could specifically identify ERGs. The results reveal a significant impact of chloroplast redox signals on distinct nuclear gene groups including genes for the mitochondrial electron transport chain, tetrapyrrole biosynthesis, carbohydrate metabolism, and signaling lipid synthesis. These expression profiles are clearly different from those observed in response to the reduction of photosynthetic electron transport by high light treatments. Thus, the ERGs identified are unique to redox imbalances in photosynthetic electron transport and were then used for analyzing potential redox-responsive cis-elements, trans-factors, and chromosomal regulatory hot spots. The data identify a novel redox-responsive element and indicate extensive redox control at transcriptional and chromosomal levels that point to an unprecedented impact of redox signals on epigenetic processes.

关键词： plastidial redox signaling,early redox-regulated gene Arabidopsis thaliana Molecular Plant

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...