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Open Journal of Modern Hydrology 2013年第4期3卷 214-225页

作者： Kronenberg Rico güttler Tino Franke Johannes Bernhofer christian Meteorology Technische Universitat DresdenDresdenGermany Mathematical Modelling Bauman Moscow State Technical UniversityMoscowRussia

This study presents an extended version of a single site daily weather generator after Richardson. The model is driven by daily precipitation series derived by a first-order two-state Markov chain and considers the annual cycle of each meteorological variable. The evaluation of its performance was done by deploying its synthetic time series into the physical based hydrological model BROOK90. The weather generator was applied and tested for data from the Anchor Station at the Tharandt Forest, germany. Additionally its results were compared to the output of another weather generator with spell-length approach for the precipitation series (LARS-Wg). The comparison was distinguished into a meteoro-logical and a hydrological part in terms of extremes, monthly and annual sums and averages. Extreme events could be preserved adequately by both models. Nevertheless a general underestimation of rare events was observed. Natural correlations between vapour pressure and minimum temperature could be conserved as well as annual cycles of the hydro-logical and meteorological regime. But the simulated spectrums of extremes, especially, of precipitation and temperature, are more limited than the observed spectrums. While LARS-Wg already finds application in practice, the results show that the data derived from the presented weather generator is as useful and reliable as those from the established model for the simulation of the water balance.

关键词： Richardson Model Weather generator BROOK90 Synthetic Time Series LARS-Wg Forest Water Balance Taylor Diagram Cumulative Periodogram

Carbon dioxide exchange processes over the grassland ecosystems in semiarid areas of China

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Science China Earth Sciences 2012年第4期55卷 644-655页

作者： DU Qun LIU HuiZhi WANg Lei HUANg JianPing ZHANg Wu christian BERNHOFER State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China graduate University of Chinese Academy of Sciences Beijing 100049China College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000China Institute of Hydrology and Meteorology Dresden University of TechnologyDresden 01737Germany

Based on the carbon fluxes measured over the grassland ecosystems in Inner Mongolia （Ug79 site）, Loess Plateau （SACOL site）, and Tongyu, Jilin Province （TY site） in the semiarid areas from 2007 to 2008 with the eddy covariance method, we have investigated the carbon exchange processes over semiarid grassland ecosystem and its main affecting environmental variables. The precipitations at Ug79 and TY sites in 2007 were below the historical average, especially for TY site, which was 50% be- low the historical average annual precipitation. The precipitation in SACOL site was close to average in 2007 but below average in 2008. The variation of monthly diurnal average NEE showed that the diurnal mean NEE decreased in the order of TY site, Ug79 site, and SACOL site. However, a longer net carbon uptake period was observed at SACOL site. The diurnal course of NEE at Ug79 site was similar between 2007 and 2008. The diurnal average NEE remained large during July and August in growing sea- son （May to September） at Ug79 site, with maximum values approaching 0.08 mg C m^-2 s^-1 in August of 2008. The diurnal av- erage NEE of 2007 was larger than 2008 at SACOL site, with maximum values of 0.07 mg C m^-2 sq in September of 2007. A shorter carbon uptake period was recorded in 2007 at TY site, lasting from July to August. A larger diurnal average NEE oc- curred in 2008 at TY site, with maximum values of 0.12 mg C m^-2 s^-1. The ecosystem respirations of three sites were controlled by both soil temperature and soil volumetric water content （at a depth of 5 cm below the land surface）. Both Ug79 site and SACOL site acted as a carbon sink during the growing periods of 2007 and 2008. Annual NEE in the growing seasons of 2007 and 2008 ranged from -68 to -50 g C m^-2 at Ug79 site and from -109 to -55 g C m^-2at SACOL site. Alternation between car- bon source and carbon sink was found at TY site, with respective values of annual NEE in the growing seasons of 0.32 g C m^-2 and -73 g C m^-2 i

关键词： semiarid grassland ecosystem carbon flux eddy covariance method

The role of mechanotransduction versus hypoxia during simulated orthodontic compressive strain——an in vitro study of human periodontal ligament fibroblasts

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International Journal of Oral Science 2019年第4期11卷 315-324页

作者： Niklas Ullrich Agnes Schroder Jonathan Jantsch gerrit Spanier Peter Proff christian Kirschneck University Medical Centre of Regensburg Franz-Josef-Strauβ-Allee 11D-93053 RegensburgGermany Department of Orthodontics University Medical Centre of RegensburgFranz-Josef-Strauβ-Allee 11D-93053 RegensburgGermany Department of Medical Microbiology and Hygiene University Medical Centre of RegensburgFranz-Josef-Strauβ-Allee 11D-93053 RegensburgGermany Department of Cranio-Maxillo-Facial Surgery University Medical Centre of RegensburgFranz-Josef-Strauβ-Allee 11D-93053 RegensburgGermany

During orthodontic tooth movement(OTM)mechanical forces trigger pseudo-inflammatory,osteoclastogenic and remodelling processes in the periodontal ligament(PDL)that are mediated by PDL fibroblasts via the expression of various signalling *** far,it is unknown whether these processes are mainly induced by mechanical cellular deformation(mechanotransduction)or by concomitant hypoxic conditions via the compression of periodontal blood *** primary PDL fibroblasts were randomly seeded in conventional six-well cell culture plates with O2-impermeable polystyrene membranes and in special plates with gas-permeable membranes(Lumox?,Sarstedt),enabling the experimental separation of mechanotransducive and hypoxic effects that occur concomitantly during *** simulate physiological orthodontic compressive forces,PDL fibroblasts were stimulated mechanically at 2 g·cm?2 for 48 h after 24 h of *** quantified the cell viability by MTT assay,gene expression by quantitative real-time polymerase chain reaction(RT-qPCR)and protein expression by western blot/enzyme-linked immunosorbent assays(ELISA).In addition,PDL-fibroblast-mediated osteoclastogenesis(TRAP+cells)was measured in a 72-h coculture with RAW264.7 *** expression of HIF-1α,COX-2,PgE2,VEgF,COL1A2,collagen and ALPL,and the RANKL/OPg ratios at the mRNA/protein levels during PDL-fibroblast-mediated osteoclastogenesis were significantly elevated by mechanical loading irrespective of the oxygen supply,whereas hypoxic conditions had no significant additional *** cellular–molecular mediation of OTM by PDL fibroblasts via the expression of various signalling molecules is expected to be predominantly controlled by the application of force(mechanotransduction),whereas hypoxic effects seem to play only a minor *** the context of OTM,the hypoxic marker HIF-1αdoes not appear to be primarily stabilized by a reduced O2 supply but is rather stabilised mechanically.

关键词： RAW264.7 periodontal mec

Combinatorial Performance Mapping of Near-NMC111 Li-ion Cathodes

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Journal of Materiomics 2022年第2期8卷 437-445页

作者： Daniel Commandeur christian Sabado Thomas E.Ashton Jawwad A.Darr Department of Chemistry University College London20 Gordon StreetLondonWC1H 0AJUK

A combinatorial library of twenty-three,phase pure,near-NMC111(LiNi_(0.33) Mn_(0.33)Co_(0,33)O_(2))composi-tions were synthesised and their electrochemical performance,was mapped(in lithium ion half-cells).Each of the 23 compositions was made in series,using a two-step process of 1)a rapid initial contin-uous hydrothermal precipitation,followed by 2)solid state *** 23 lithiated NMC samples were then subjected to analytical methods including electron microscopy(selected samples),Powder X-ray Diffraction and electrochemical tests in half cell Li-ion configurations versus Li metal.A sample with a Ni:Mn:Co(NMC)ratio of 39:28:33,revealed a specific capacity of 150 mA h g^(-1) at a C/20 rate,which was 63 and 43% greater capacity than NMC111 and NMC433 samples produced in this work,*** sample with NMC ratio 47:25:28,showed the best capacity retention characteristics,retaining 70%of its C/20 capacity at 1C,after 40 *** analysis of all the samples by cyclic voltammetry and elec-trochemical impedance spectroscopy,allowed compositional mapping of diffusion ***,the mapping data revealed a gradual change of properties across compositional space,which has vali-dated our combinatorial approach and allowed identification of the optimum performing near-NMC111 cathode materials.

关键词： Li-ion Batteries Li-ion Cathode NMC Combinatorial Continuous hydrothermal flow synthesis Rate capability

Hydrodynamic Anisotropy Effects on Radiation-Mixed Convection Interaction in a Vertical Porous Channel

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Applied Mathematics 2016年第1期7卷 22-39页

作者： gé rard Degan christian Akowanou Latif Fagbemi Joël Zinsalo Laboratoire d’Energé tique et de Mé canique Appliqué es (LEMA) Ecole Polytechnique d’Abomey-Calavi (EPAC) Universit&eacute d’Abomey-Calavi (UAC) Cotonou B&eacute nin Department of Mechanical Engineering Ecole de Technologie Sup&eacute rieure Montr&eacute al Canada

The effects of hydrodynamic anisotropy on the mixed-convection in a vertical porous channel heated on its plates with a thermal radiation are investigated analytically for fully developed flow regime. The porous medium is anisotropic in permeability whose principal axes are oriented in a direction that is oblique to the gravity. The generalized Brinkman-extended Darcy model which allows the no-slip boundary-condition on solid wall is used in the formulation of the problem. The flow reversal, the thermal radiation influence for natural, and forced convection are considered in the limiting cases for low and high porosity media. It was found that the anisotropic permeability ratio, the orientation angle of the principal axes of permeability and the radiation parameter affected significantly the flow regime and the heat transfer.

关键词： Mixed-Convection Thermal Radiation Anisotropic Porous Medium Flow Reversal Heat Transfer

Trade-offs between ecosystem service provision and the predisposition to disturbances: a NFI-based scenario analysis

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Forest Ecosystems 2020年第3期7卷 349-365页

作者： christian Temperli Clemens Blattert golo Stadelmann Urs-Beat Brändli Esther Thürig Swiss Federal Institute for Forest Snow and Landscape Research WSL8903BirmensdorfSwitzerland University of Jyväskylä FI-40014JyväskyläFinland

Background: Scenario analyses that evaluate management effects on the long-term provision and sustainability of forest ecosystem services and biodiversity(ESB) also need to account for disturbances. The objectives of this study were to reveal potential trade-offs and synergies between ESB provision and disturbance predisposition at the scale of a whole ***: The empirical scenario model MASSIMO was used to simulate forest development and management from years 2016 to 2106 on 5086 sample plots of the Swiss National Forest Inventory(NFI). We included a businessas-usual(BAU) scenario and four scenarios of increased timber harvesting. Model output was evaluated with indicators for 1) ESB provision including a) timber production, b) old-growth forest characteristics as biodiversity proxies and c) protection against rockfall and avalanches and 2) for a) storm and b) bark beetle ***: The predisposition indicators corresponded well(AUC: 0.71–0.86) to storm and insect(mostly bark beetle)damage observations in logistic regression models. Increased timber production was generally accompanied with decreased predisposition(storm: >-11%, beetle: >-37%, depending on region and scenario), except for a scenario that promoted conifers where beetle predisposition increased(e.g. + 61% in the Southern Alps). Decreased disturbance predisposition and decreases in old-growth forest indicators in scenarios of increased timber production revealed a trade-off situation. In contrast, growing stock increased under BAU management along with a reduction in conifer proportions, resulting in a reduction of beetle predisposition that in turn was accompanied by increasing old-growth forest indicators. Disturbance predisposition was elevated in NFI plots with high avalanche and rockfall protection ***: By evaluating ESB and disturbance predisposition based on single-tree data at a national scale we bridged a gap between detailed, stand-scale assessments and

关键词： Disturbance Ecosystem services Empirical model Forest inventory Scenario analysis

Emerging R&D on membranes and systems for water reuse and desalination

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Chinese Journal of Chemical Engineering 2019年第7期27卷 1578-1585页

作者： Tai-Shung Chung Dieling Zhao Jie gao Kangjia Lu Chunfeng Wan Martin Weber christian Maletzko Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117585Singapore Advanced Materials and Systems Research BASF SERAP/OUB - B167056 LudwigshafenGermany Performance Materials BASF SEG-PMFSU-F20667056 LudwigshafenGermany

Sustainable production of clean water is a global *** we firmly believe that membrane technologies are one of the most promising solutions to tackle the global water challenges,one must reduce their energy consumption and fouling propensity for broad sustainable *** addition,different membranes face various challenges in their specific applications during long-term *** this short review,we will summarize the recent progresses in emerging membrane technologies and system integration to advance and sustain water reuse and desalination with discussion on their challenges and perspectives.

关键词： Membrane technology Water reuse Desalination Hybrid system Nanomaterials

Versatile multiplexed super-resolution imaging of nanostructures by Quencher-Exchange-PAINT

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Nano Research 2018年第12期11卷 6141-6154页

作者： Tobias Lutz Alexander H.Clowsley Ruisheng Lin Stefano Pagliara Lorenzo Di Michele christian Soeller Living Systems Institute & Biomedical Physics University of ExeterExeter EX44QDUK Cavendish Laboratory University of CambridgeCambridge CB30HEUK

The optical super-resolution technique DNA-PAINT (Point Accumulation Imaging in Nanoscale Topography) provides a flexible way to achieve imaging of nanoscale structures at ∼10-nanometer resolution. In DNA-PAINT, fluorescently labeled DNA “imager” strands bind transiently and with high specificity to complementary target “docking” strands anchored to the structure of interest. The localization of single binding events enables the assembly of a super-resolution image, and this approach effectively circumvents photobleaching. The solution exchange of imager strands is the basis of Exchange-PAINT, which enables multiplexed imaging that avoids chromatic aberrations. Fluid exchange during imaging typically requires specialized chambers or washes, which can disturb the sample. Additionally, diffusional washout of imager strands is slow in thick samples such as biological tissue slices. Here, we introduce Quencher-Exchange-PAINT—a new approach to Exchange-PAINT in regular open-top imaging chambers—which overcomes the comparatively slow imager strand switching via diffusional imager washout. Quencher-Exchange-PAINT uses “quencher” strands, i.e., oligonucleotides that prevent the imager from binding to the targets, to rapidly reduce unwanted single-stranded imager concentrations to negligible levels, decoupled from the absolute imager concentration. The quencher strands contain an effective dye quencher that reduces the fluorescence of quenched imager strands to negligible levels. We characterized Quencher-Exchange-PAINT when applied to synthetic, cellular, and thick tissue samples. Quencher-Exchange-PAINT opens the way for efficient multiplexed imaging of complex nanostructures, e.g., in thick tissues, without the need for washing steps.

关键词： super-resolution microscopy fluorescence imaging DNA nanotechnology DNA-PAINT fluorescence quencher

Long-term results of an anatomically implanted hip arthroplasty with a short stem prosthesis (MiniHip^(TM))

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World Journal of Orthopedics 2018年第10期9卷 210-219页

作者： Lars V von Engelhardt Andreas Breil-Wirth christian Kothny Jorn Bengt Seeger christian grasselli Joerg Jerosch Faculty of Health University of Witten/Herdecke Department of Trauma Surgery Orthopedics and Sports Medicine Katholisches Karl-Leisner Klinikum Department of Orthopedics Trauma Surgery and Sports MedicineJohanna Etienne Hospital Munich Ortho Center Department of Orthopaedics and Orthopaedic Surgery University Hospital Giessen and Marburg Department of Orthopaedics and Traumatology Waldburg-Zeil Clinic Tettnang

AIM To evaluate the clinical and radiological outcome nineand ten years after short-stemmed, bone preserving and anatomical hip arthroplasty with the MiniHip^(TM) system. METHODS In a prospective study, 186 patients underwent hip arthroplasty with a partial neck preserving short stem(MiniHip^(TM), Corin). Elderly patients were not excluded from this study, thus the mean age at the time of surgery was 59.3 years(range 32 to 82 years). Surgery and the follow-up assessments were performed at two Centers. Up until now, the mean follow-up was 112.5 ± 8.2 mo. The Oxford Hip Score(OHS) and the Hip Dysfunction Osteoarthritis and Outcome Score(HOOS) was assessed pre-and each year after surgery. The clinical follow-up was accompanied by standardized a.p. and axial radiological examinations. Periprosthetic lucencies, hypertrophies within the gruen zones one to fourteen were assessed. A subsidence of the stem was investigated according to Morray and heterotopic ossifications were assessed according to *** The OHS and HOOS improved from 18 ± 3.3 to 46 ± 2.0 and from 30 ± 8.3 to 95 ± 4.6 points, P garding age, etiology, friction pairings, etc.,(P > 0.05). Two stems were revised due to a symptomatic subsidence four and twelve months postoperatively. Thus, the survivorship for aseptic loosening at nine to ten years was 98.66%. Including one stem revision due to a symptomatic exostosis, bursitis and thigh pain as well as one revision because of a septic stem loosening, the overall survival for the stem with revision for any reason was 97.32%. Besides one asymptomatic patient, radiological signs of a proximal stress-shielding, such as bone resorptions within the proximal gruen zones, were not noticed. Findings suggesting a distal loading, e.g., bony hypertrophies or bone appositions of more than 2 mm, were also not detected. CONCLUSION Regarding these first long-term results on the MiniHip^(TM), the implant performed excee

关键词： Primary hip arthroplasty Long-term results Short stem endoprothesis Prospective follow-up study Stress-shielding

Classification of higher- and lower-mileage runners based on running kinematics

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Journal of Sport and Health Science 2019年第3期8卷 249-257页

作者： christian A.Clermont Angkoon Phinyomark Sean T.Osis Reed Ferber Faculty of Kinesiology University of Calgary Institute for Scientific Interchange (ISI )Foundation Running Injury Clinic Faculty of Nursing University of Calgary

Background: Running-related overuse injuries can result from the combination of extrinsic(e.g., running mileage) and intrinsic risk factors(e.g.,biomechanics and gender), but the relationship between these factors is not folly understood. Therefore, the first purpose of this study was to determine whether we could classify higher-and lower-mileage runners according to differences in lower extremity kinematics during the stance and swing phases of running gait. I he second purpose was to subgroup the runners by gender and determine whether we could classify higherand lower-mileage runners in male and female ***: Participants were allocated to the "higher-mileage" group(≥32 km/week; n= 41(30 females)) or to the "lower-mileage" group(≤25 km;n= 40(29 females)). Three-dimensional kinematic data were collected during 60 s of treadmill running at a self-selected speed(2.61 ± 0.23 m/s).A support vector machine classifier identified kinematic differences between higher-and lower-mileage groups based on principal component ***: Higher-and lower-mileage runners(both genders) could be separated with 92.59% classification accuracy. When subgrouping by gender,higher-and lower-mileage female runners could be separated with 89.83% classification accuracy, and higher-and lower-mileage male runners could be separated with 100% classification ***: These results demonstrate there are distinct kinematic differences between subgroups related to both mileage and gender, and that these factors need to be considered in future research.

关键词： Biomechanics Clinical biomechanics gait analysis Kinematics Motion analysis:Running mileage Running subgroups