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PHiFA—A tool for numerical propagation of high-fidelity astrodynamics

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Astrodynamics 2022年第2期6卷 189-204页

作者： Yang Yang Erik.klein Changyong He Han Cai Yan Zhang School of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518000China TU Braunschweig Institut for Space Systems38108 BraunschweigGermany ENSG-Géomatics Institut national de l’information géographique et forestière(IGN)F-77455 Marne-la-ValléeFrance School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

This paper presents a tool for the numerical propagation of high-fidelity astrodynamics,called *** coupled orbit–attitude dynamics for space objects are modeled by considering various types of perturbative forces and *** methods have been implemented to calculate the surface forces:the area matrix method and the beam *** beam method is more precise as it discretizes the source media(e.g.,sunlight and aerodynamic wind)and the surface of the target into multiple rays and finite elements,respectively,and then accumulates the effect of each *** PHiFA tool was tested and validated using a 3U CubeSat model and the defunct European environment satellite(Envisat)model.

关键词： coupled orbit-attitude dynamics surface force modeling beam method European environment satellite (Envisat)

Changes in culm surface temperature with maturity of the bamboo species Guadua angustifolia

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Journal of Forestry Research 2016年第2期27卷 419-425页

作者： Nils Nolke Juan Carlos Camargo Garcia Christoph klein Andrea Polle Chair of Forest Inventory and Remote Sensing Universitat GottingenBusgenweg 537077 GottingenGermany Faculty of Environmental Sciences Technological Universityof PereiraLa JulitaPereiraColombia Department of Forest Botany and Tree Physiology Universiat GottingenBiJsgenweg 237077 GottingenGermany

We used thermal images of bamboo culms of Guadua angustifolia kunth to analyze the relationship between culm surface temperature and maturity, driven by the hypothesis that young culms may exhibit lower surface temperatures than old ones. The culm surface temperature shows small but constant differences between three age classes of 1, 2, and 3 years. Our findings indicate that surface temperature may be applied as an additional indi- cator to support the determination of maturity of guadua culms besides the visual assessment of the culms.

关键词： Bamboo culms Thermal images Bamboowood quality

Catalytic domain of PDC-E2 contains epitopes recognized by antimitochondrial antibodies in primary biliary cirrhosis

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World Journal of Gastroenterology 2010年第8期16卷 973-981页

作者： Sandra Braun Christoph Berg Sandra Buck Michael Gregor Reinhild klein Department of Internal Medicine University of Tuebingen Department of Internal Medicine University of Tuebingen

AIM:To search for further immunodominant peptides of the pyruvate dehydrogenase complex E2-component (PDC-E2) recognized by antimitochondrial antibodies (AMA) in primary biliary cirrhosis (PBC). METHODS:Sera from 95 patients with PBC were tested by enzyme-linked immunosorbent assay against 33 synthetic overlapping peptides (25 amino acids; aa) covering the entire length of the E2-subunit of PDC-E2. Furthermore,the inner lipoyl peptide 167-184 was used in an unlip oylated and a lipoylated form as well as coupled to ovalbumin. Sera from 11 AMA negative/ANA posit ive PBC patients,63 patients with other liver disorders and 22 healthy blood donors served as ***:Of the 95 PBC-sera,74% reacted with the peptide 475-499 and 58% with the pept ide 407-431 located within the catalytic domain of PDC-E2. Patients with other disorders or healthy controls were positive in only up to 18%. Antibodies to the unlipoylatedand lip oylated pept ide 167-184 within the inner lipoyl domain were found in only 5% and 11% of the PBC sera,respectively; using ovalbumin-coupled peptides,the incidence increased up to 57% (unlipoylated form). CONCLUSION:Peptides within the catalytic site of PDC-E2 rather than the previously reported lipoyl binding peptide 167-184 may represent major immunodomin ant epitopes recognized by AMA in PBC.

关键词： Anti-M2 Epitope mapping E2-subunit Pyruvate dehydrogenase complex Inner lipoyl domain Active site Catalytic domain Primary biliary cirrhosis

Metabolic activity of Streptococcus mutans biofilms and gene expression during exposure to xylitol and sucrose

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International Journal of Oral Science 2014年第4期6卷 195-204页

作者： Eva-Maria Decker Christian klein Dimitri Schwindt Christiane von Ohle Department for Pediatric and Operative Dentistry Periodontology and Endodontology Center of Dentistry Oral Medicine and Maxillofacial Surgery University of Tbingen Private Practice Zahngesundheit Waiblingen

The objective of the study was to analyse Streptococcus mutans biofilms grown under different dietary conditions by using multifaceted methodological approaches to gain deeper insight into the cariogenic impact of carbohydrates. S. mutans biofilms were generated during a period of 24 h in the following media： Schaedler broth as a control medium containing endogenous glucose, Schaedler broth with an additional 5% sucrose, and Schaedler broth supplemented with 1% xylitol. The confocal laser scanning microscopy（CLSM）-based analyses of the microbial vitality, respiratory activity（5-cyano-2,3-ditolyl tetrazolium chloride, CTC） and production of extracellular polysaccharides（EPS） were performed separately in the inner, middle and outer biofilm layers. In addition to the microbiological sample testing, the glucose/sucrose consumption of the biofilm bacteria was quantified, and the expression of glucosyltransferases and other biofilm-associated genes was investigated. Xylitol exposure did not inhibit the viability of S. mutans biofilms, as monitored by the following experimental parameters： culture growth, vitality, CTC activity and EPS production. However,xylitol exposure caused a difference in gene expression compared to the control. Gtf C was upregulated only in the presence of *** xylitol exposure, gtf B was upregulated by a factor of 6, while under sucrose exposure, it was upregulated by a factor of *** with glucose and xylitol, sucrose increased cell vitality in all biofilm layers. In all nutrient media, the intrinsic glucose was almost completely consumed by the cells of the S. mutans biofilm within 24 h. After 24 h of biofilm formation, the multiparametric measurements showed that xylitol in the presence of glucose caused predominantly genotypic differences but did not induce metabolic differences compared to the control. Thus, the availability of dietary carbohydrates in either a pure or combined form seems to affect the cariogenic potential of

关键词： biofilms 5-cyano-2 3-ditolyl tetrazolium chloride extracellular polysaccharides gene expression Streptococcus mutans sucrose viability xylitol

Preoperative imaging in staghorn calculi, planning and decision making in management of staghorn calculi

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Asian Journal of Urology 2020年第2期7卷 87-93页

作者： Ilan klein Jorge Gutierrez-Aceves Department of Urology Wake Forest University Baptist Medical CenterWinston-SalemNCUSA

Objective:Staghorn calculi present a particular and challenging entity of stone *** is associated with lower stone-free rates and higher complication rates compared to non-staghorn *** this review we looked for the most relevant data on preoperative imaging and access planning to help decision making for percutaneous surgery with this complex ***:We conducted a PubMed search of publications in the past 2 decades that include relevant information on the planning for management of staghorn ***-contrast computerized tomography(NCCT)is indeed the standard imaging tool for percutaneous nephrolithotomy(PCNL);additional tools such as three-dimensional computed tomography(CT)reconstruction of the staghorn calculus may help plan access in complex *** guided percutaneous access may be considered for staghorn stones when planning upper pole access in kidney malposition or complex intrarenal anatomy or with complex body *** doppler ultrasound and real-time virtual sonography can *** technologies to improve kidney access such as Uro Dyna-CT or electromagnetic sensor have been reported,but have not shown utilization in staghorn *** morphometry-based prediction algorithms may predict the number of tract(s)and stage(s)for PCNL *** pole access can be equally effective as upper pole when planning for staghorn and complex stones,with significantly less complications rate;Stone-Tract length-Obstruction-Number of involved calyces-Essence of stone density(STONE)nephrolithometry seems to be the best system to predict outcomes of PCNL in staghorn *** is a growing trend of endoscopic combined intrarenal surgery(ECIRS)in concordance with PCNL to treat larger *** management of staghorn calculi is an undesired option,but can be an alternative for a carefully selected group of high-risk ***:Staghorn stones may lead to deterioration of renal function and l

关键词： Staghorn stone Preoperative planning Imaging kidney access

Corrigendum to“The new ichnotaxon Eubrontes nobitai *** other saurischian tracks from the Lower Cretaceous of Sichuan Province and a review of Chinese Eubrontes-type tracks”[Journal of Palaeogeography(10)(2021)17]

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Journal of Palaeogeography 2024年第2期13卷 372-372页

作者： Li-Da Xing Martin G. Lockley Hendrik.klein Li-Jun Zhang Anthony Romilio W. Scott Persons IV Guang-Zhao Peng Yong Ye Miao-Yan Wang State key Laboratory of Biogeology and Environmental Geology China University of Geosciences Beijing 100083 China School of the Earth Sciences and Resources China University of Geosciences Beijing 100083 China Dinosaur Trackers Research Group University of Colorado Denver Denver 80217 USA Saurierwelt Paläontologisches Museum Alte Richt 7 92318 Neumarkt Germany Institute of Resources and Environment Key Laboratory of Biogenic Traces and Sedimentary Minerals of Henan Province Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic Region Henan Polytechnic University Jiaozuo 454003 Henan Province China School of Biological Sciences The University of Queensland Brisbane Queensland 4072 Australia Mace Brown Museum of Natural History Department of Geology and Environmental Geosciences College of Charleston Charleston 29401 USA Zigong Dinosaur Museum Zigong 643013 Sichuan Province China

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Peptide aptamer-mediated modulation of prion protein α-cleavage as treatment strategy for prion and other neurodegenerative diseases

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Neural Regeneration Research 2018年第12期13卷 2108-2110页

作者： Antonia N.klein Erica Corda Sabine Gilch Department of Ecosystem and Public Health Faculty of Veterinary Medicine University of Calgary Calgary Prion Research Unit University of Calgary Hotchkiss Brain Institute University of Calgary

Despite intensive research,most neurodegenerative diseases cannot be cured and for some of them no treatment is available to increase survival or quality of *** the latter are prion diseases,fatal and transmissible ne... 详细信息

关键词： Peptide aptamer-mediated modulation of prion protein cleavage as treatment strategy for prion and other neurodegenerative diseases

Effects of grassland management, endophytic fungi and predators on aphid abundance in two distinct regions

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Journal of Plant Ecology 2014年第5期7卷 490-498页

作者： Carmen Börschig Alexandra-M.klein Jochen krauss Agroecology Department of Crop SciencesUniversity of GöttingenGrisebachstrasse 6D-37075 GöttingenGermany Ecosystem Functions Institute of EcologyUniversity of LüneburgScharnhorstrasse 1D-21335 LüneburgGermany Nature Conservation and Landscape Ecology Institute of Earth and Environmental SciencesUniversity of FreiburgTennenbacherstr.4D-79106 FreiburgGermany Department of Animal Ecology and Tropical Biology University of WürzburgBiocentreAm HublandD-97074 WürzburgGermany

Aims Fungal endophytes of cool-season grass species produce alkaloids toxic to herbivores,affecting food webs in agricultural and natural *** studies about the effects of endophytes on herbi-vores are rare and show contradictory results,leading to uncertain conclusions about the nature of endophyte-grass *** asked whether the environmental contexts of local and regional scales and predation could modify the effects of endophytes on *** In a full factorial field experiment,we quantified the abundance of the aphid species Rhopalosiphum padi on the potted host grass Lolium perenne,which was either infected or uninfected with the endophytic fungus Neotyphodium *** were either excluded or had free access to the pots with the *** hun-dred and sixty grass pots were located in two regions on altogether 40 grassland sites,half of the sites intensively and half extensively *** tested the importance of endophyte infection,study region,management intensity of grasslands,predation and all two-way interactions on aphid *** Findings Endophyte infection reduced aphid abundance significantly in one study region *** both regions,we found that the impacts of aphidophagous predators and grassland management intensity on aphid abundance were substantially stronger and more consistent than that of endophytes on aphid *** excluding preda-tors and pots placed on extensive grasslands contained higher aphid *** impact of predators and management on aphid abundance were not modified by the *** conclude that the effect of endophytes on herbivores can be weak in field experi-ments and depends on environmental context at a regional ***,more field research efforts are necessary to detect the rela-tive importance of endophytes and the environmental context on biotic interactions in ecosystems.

关键词： bottom-up control microorganism multi-trophic interaction predator exclosure top-down control

Mixed reality based respiratory liver tumor puncture navigation

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Computational Visual Media 2019年第4期5卷 363-374页

作者： Ruotong Li Weixin Si Xiangyun Liao Qiong Wang Reinhard klein Pheng-Ann Heng Institute of Computer Science II University of Bonn53115 BonnGermany Shenzhen key Laboratory of Virtual Reality and Human Interaction Technology Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesChina Department of Computer Science and Engineering Chinese University of Hong KongHong KongChina

This paper presents a novel mixed reality based navigation system for accurate respiratory liver tumor punctures in radiofrequency ablation(RFA).Our system contains an optical see-through head-mounted display device(OST-HMD),Microsoft Holo Lens for perfectly overlaying the virtual information on the patient,and a optical tracking system NDI Polaris for calibrating the surgical utilities in the surgical *** with traditional navigation method with CT,our system aligns the virtual guidance information and real patient and real-timely updates the view of virtual guidance via a position tracking *** addition,to alleviate the difficulty during needle placement induced by respiratory motion,we reconstruct the patientspecific respiratory liver motion through statistical motion model to assist doctors precisely puncture liver *** proposed system has been experimentally validated on vivo pigs with an accurate real-time registration approximately 5-mm mean FRE and TRE,which has the potential to be applied in clinical RFA guidance.

关键词： mixed reality human computer interaction statistical motion model