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Decreasing nutrient concentrations in soils and trees with increasing elevation across a treelineecotone in Rolwaling Himal, Nepal

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Journal of Mountain Science 2017年第5期14卷 843-858页

作者： Simon DROllINGER Michael MUllER Timo KOBl Niels schwab Jurgen BOHNER Udo SCHICKHOFF Thomas SCHOlTEN Geoecology Department of Geography and Regional Research University of Vienna Vienna Austria Soil Science and Geomorphology Department of Geosciences Uniuersity of Tubingen Tubingen Germany CEN Center for Earth System Research and Sustainability Institute of Geography University of Hamburg Hamburg Germany

At a global scale, tree growth in alpine treeline ecotones is limited by low temperatures. At a local scale, however, tree growth at its upper limit depends on multiple interactions of influencing factors and mechanisms. The aim of our research was to understand local scale effects of soil properties and nutrient cycling on tree growth limitation, and their interactions with other abiotic and biotic factors in a near-natural Himalayan treeline ecotone. Soil samples of different soil horizons, litter, decomposition layers, and foliage samples of standing biomass were collected in four altitudinal zones along three slopes, and were analysed for exchangeable cations and nutrient concentrations, respectively. Additionally, soil and air temperature, soil moisture, precipitation, and tree physiognomy patterns were evaluated. Both soil nutrients and foliar macronutrient concentrations of nitrogen(N), magnesium(Mg), potassium(K), and foliar phosphorus(P) decrease significantly with elevation. Foliar manganese(Mn) concentrations, bycontrast, are extraordinarily high at high elevation sites. Potential constraining factors on tree growth were identified using multivariate statistical approaches. We propose that tree growth, treeline position and vegetation composition are affected by nutrient limitation, which in turn, is governed by low soil temperatures and influenced by soil moisture conditions.

关键词： Foliar nutrients Himalaya Nitrogen Nutrient cycling Podzol Treeline

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The welcoming house

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作者： schwab Jane. Smith Cindy.

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Polyethylene glycol has immunoprotective effects on sciatic allografts, but behavioral recovery and graft tolerance require neurorrhaphy and axonal fusion

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Neural Regeneration Research 2025年第4期20卷 1192-1206页

作者： Tyler A.Smith liwen Zhou Cameron l.Ghergherehchi Michelle Mikesh Cathy Z.Yang Haley O.Tucker JuliAnne Allgood Jared S.Bushman George D.Bittner Department of Molecular Biosciences University of Texas at AustinAustinTXUSA Department of Neuroscience University of Texas at AustinAustinTXUSA Division of Pharmaceutical Sciences University of WyomingLaramieWYUSA

Behavioral recovery using(viable)peripheral nerve allografts to repair ablation-type(segmental-loss)peripheral nerve injuries is delayed or poor due to slow and inaccurate axonal ***,such peripheral nerve allografts undergo immunological rejection by the host immune *** contrast,peripheral nerve injuries repaired by polyethylene glycol fusion of peripheral nerve allografts exhibit excellent behavioral recovery within weeks,reduced immune responses,and many axons do not undergo Wallerian *** relative contribution of neurorrhaphy and polyethylene glycol-fusion of axons versus the effects of polyethylene glycol per se was unknown prior to this *** hypothesized that polyethylene glycol might have some immune-protective effects,but polyethylene glycol-fusion was necessary to prevent Wallerian degeneration and functional/behavioral *** examined how polyethylene glycol solutions per se affect functional and behavioral recovery and peripheral nerve allograft morphological and immunological responses in the absence of polyethylene glycol-induced axonal ***-type sciatic nerve injuries in outbred Sprague–Dawley rats were repaired according to a modified protocol using the same solutions as polyethylene glycol-fused peripheral nerve allografts,but peripheral nerve allografts were loose-sutured(loose-sutured polyethylene glycol)with an intentional gap of 1–2 mm to prevent fusion by polyethylene glycol of peripheral nerve allograft axons with host *** to negative control peripheral nerve allografts not treated by polyethylene glycol and in contrast to polyethylene glycol-fused peripheral nerve allografts,animals with loose-sutured polyethylene glycol peripheral nerve allografts exhibited Wallerian degeneration for all axons and myelin degeneration by 7 days postoperatively and did not recover sciatic-mediated behavioral functions by 42 days *** morphological signs of rejection,such as col

关键词： allograft rejection axotomy macrophage myelin nerve repair polyethylene glycol(PEG) sciatic nerve T cell transplantation Wallerian degeneration

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UGT74AF3 enzymes specifically catalyze the glucosylation of 4-hydroxy-2,5-dimethylfuran-3(2H)-one,an important volatile compound in Camellia sinensis

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Horticulture Research 2020年第1期7卷 2433-2443页

作者： Yongxian Chen Xiangyang Guo Ting Gao Na Zhang Xiaochun Wan Wilfried schwab Chuankui Song State Key laboratory of Tea Plant Biology and Utilization International Joint Laboratory on Tea Chemistry and Health EffectsAnhui Agricultural University230036 HefeiAnhuiP.R.China Biotechnology of Natural Products Technische Universität MünchenLiesel-Beckmann-Str.185354 FreisingGermany

4-Hydroxy-2,5-dimethylfuran-3(2H)-one(HDMF)is an important odorant in some fruits,and is proposed to play a crucial role in the caramel-like notes of some ***,its biosynthesis and metabolism in tea plants are still ***,HDMF glucoside was unambiguously identified as a native metabolite in tea plants.A novel glucosyltransferase UGT74AF3a and its allelic protein UGT74AF3b specifically catalyzed the glucosylation of HDMF and the commercially important structural homologues 2(or 5)-ethyl-4-hydroxy-5(or 2)-methylfuran-3(2H)-one(EHMF)and 4-hydroxy-5-methylfuran-3(2H)-one(HMF)to their correspondingβ-***-directed mutagenesis of UGT74AF3b to introduce a single A456V mutation resulted in improved HDMF and EHMF glucosylation activity and affected the sugar donor preference compared with that of the wild-type control *** accumulation of HDMF glucoside was consistent with the transcript levels of UGT74AF3 in different tea *** addition,transient UGT74AF3a overexpression in tobacco significantly increased the HDMF glucoside contents,and downregulation of UGT74AF3 transcripts in tea leaves significantly reduced the concentration of HDMF glucoside compared with the levels in the *** identification of HDMF glucoside in the tea plant and the discovery of a novel-specific UDP-glucose:HDMF glucosyltransferase in tea plants provide the foundation for improvement of tea flavor and the biotechnological production of HDMF glucoside.

关键词： metabolism volatile sugar

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The Strawberry Fruit Fra a Allergen Functions in Flavonoid Biosynthesis

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Molecular Plant 2010年第1期3卷 113-124页

作者： Cristina Munoz Thomas Hoffmann Nieves Medina Escobar Felix ludemann Miguel A. Botella Victoriano Valpuesta Wilfried schwab Departamento de Biologia Molecular y Bioquimica Universidad de Malaga 29071 Malaga Spain Biomolecular Food Technology Technische Universit~t M0nchen Hochfeldweg 1 85354 Freising Germany

The strawberry Fra a I allergen is a homolog of the major birch pollen allergen Bet v 1. It is synthesized by red ripe fruits of Fragaria x ananassa while white fruits of a mutant genotype, which is known to be tolerated by individuals affected by allergy, are devoid of it. Proteomic analyses have shown that Fra a 1 is down-regulated in the tolerated white- fruited genotype along with enzymes of the anthocyanin pigment pathway. In this study, we report the spatial and tem- poral expression of three Fra a genes that encode different isoforms, and the transient RNAi-mediated silencing of the Fra a genes in strawberry fruits of the red-fruited cultivar Elsanta with an ihpRNA construct. As a consequence of reduced levels of Fra a mRNAs, fruits were obtained that produced significantly decreased levels of anthocyanins and upstream metabolites. This effect is consistent with the parallel down-regulation of the phenylalanine ammonia lyase （FaPAl） and to a lesser extent of the chalcone synthase （FaCHS） transcript levels also found in these fruits. In naturally occurring white- fruited genotypes of F. chiloensis and F. vesca, Fra a transcript levels are higher than those of the red-fruited varieties, likely to compensate for the low expression levels of FaPAl and FaCHS in these mutant genotypes. The results demonstrate that Fra a expression is directly linked to flavonoid biosynthesis and show that the Fra a allergen has an essential biological function in pigment formation in strawberry fruit.

关键词： Fragaria flavonoid anthocyanin phenylpropanoid allergen pathogenesis-related proteins.

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Inverse Problem on Heat Conduction in Heterogeneous Medium

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American Journal of Computational Mathematics 2014年第1期4卷 30-36页

作者： Albert schwab M.A. lavrentiev Institute of Hydrodynamics Siberian Branch Russian Academy of Sciences Novosibirsk Russia

Under consideration is a nonclassical stationary problem on heat conduction in a body with the pre-set surface temperature and heat flow. The body contains inclusions at unknown locations and with unknown boundaries. The body and inclusions have different constant thermal conductivities. The author explores the possibility of locating inclusions. The article presents an integral criterion based on which a few statements on identification of inclusions in a body are proved.

关键词： Heat Conduction Inclusions Defect Heterogeneous Medium Inverse Problem

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Risk of conduction disturbances following different transcatheter aortic valve prostheses:the role of aortic valve calcifications

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Journal of Geriatric Cardiology 2022年第3期19卷 167-176页

作者： Francesco Pollari Ferdinand Vogt Irena Großmann Jill Marianowicz Marie Claes Steffen Pfeiffer Johannes schwab Theodor Fischlein Cardiac Surgery Cardiovascular CenterKlinikum NürnbergParacelsus Medical UniversityNurembergGermany Cardiology Cardiovascular CenterKlinikum NürnbergParacelsus Medical UniversityNurembergGermany Radiology Klinikum NürnbergParacelsus Medical UniversityNurembergGermany

OBJECTIVES To assess the impact of prosthesis choice and aortic valve calcifications on the occurrence of conduction disturb-ances after transcatheter aortic valve implantation(TAVI).METHODS We retrospectively analyzed the preoperative clinical characteristics,electrocardiograms,contrast-enhanced mul-tidetector computed tomography scans and procedural strategies of patients who underwent TAVI in our center between January 2012 and June *** of calcium volume was performed for each aortic cusp above(aortic valve)and below(left ventricular outflow tract,lVOT)the basal *** analysis was performed to evaluate risk factors for the onset of new bundle branch block(BBB),transient and permanent atrioventricular block(tAVB,pAVB).RESUlTS A total of 569 patients were included in the *** different prostheses were implanted(Edwards Sapien XT,n=162;Edwards Sapien 3,n=240;Medtronic CoreValve,n=27;Medtronic CoreValve Evolut R,n=21;Symetis Acurate,n=56;Sy-metis Acurate neo,n=63).The logistic regression analysis for BBB showed association with baseline left anterior *** logistic regression for tAVB,found the prior valvuloplasty and the balloon post-dilatation associated with the *** left and right BBB,degree of oversizing,and lVOT calcification beneath the non-coronary cusp were associated with *** the prosthesis model,nor the use of a self-expandable prosthesis showed statistical significance with the above-men-tioned outcomes on univariate *** lVOT calcification beneath the non-coronary cusp,baseline left anterior hemiblock,right BBB,balloon post-dilatation,prior valvuloplasty and oversizing are independently associated with postprocedural conduction disturbances after *** of a self-expandable prosthesis may show a lower incidence of AVB,if applied in lower calcified aortic valves.

关键词： aortic balloon conduction

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Implications of tree species–environment relationships for the responsiveness of Himalayan krummholz treelines to climate change

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Journal of Mountain Science 2017年第3期14卷 453-473页

作者： Niels schwab Udo SCHICKHOFF Birgit BURZlE Michael MUllER Jurgen BOHNER Ram Prasad CHAUDHARY Thomas SCHOlTEN Jens OlDElAND CEN Center for Earth System Research and Sustainability Institute of GeographyUniversity of HamburgBundesstrafle 5520146 HamburgGermany Department of Geosciences Chair of Soil Science and CeomorphologyUniversity of TübingenGermany Research Centre for Applied Science and Technology&Central Department of Botany Tribhuvan UniversityNepal Biocentre Klein Flottbek University of HamburgOhnhorststr.1822609 HamburgGermany

Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. In this context, we aim at investigating the sensitivity and responsiveness of the near-natural treeline ecotone in Rolwaling Himal, Nepal, to climate warming. We analysed population densities of tree species along the treeline ecotone from closed forest stands via the krummholz belt to alpine dwarf shrub heaths （3700-4200 m） at 50 plots in 2013 and 2014. We quantified species - environment relationships, i.e. the change of environmental conditions （e.g., nutrient and thermal deficits, plant interactions） across the ecotone by means of redundancy analyses, variation partitioning and distance-based Moran＇s eigenvector maps. In particular, we focus on explaining the high competitiveness of Rhododendron campanulatum forming a dense krummholz belt and on the implications for the responsiveness of Himalayan krummholz treelines to climate change. Results indicate that treeline trees in the ecotone show species-specific responses to the influence of environmental parameters, and that juvenile and adult tree responses are modulated by environmental constraints in differing intensity. Moreover, the species - environment relationships suggest that the investigated krummholz belt will largely prevent the upward migration of other tree constrain the future response species and thus of Himalayan krummholz treelines to climate warming.

关键词： Himalaya Nepal Population structure Rhododendron campanulatum Spatial patterns Species-environment relationships Stand density Variation partitioning

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An ultra-wideband circularly polarized microstrip patch antenna loaded with split-ring resonator

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Optoelectronics letters 2025年

作者： WANG Shike XIA Dan lü lianrong QIN Juan WANG Meng REN Haiping School of Integrated Circuit Science and Engineering， Tianjin University of Technology

In this paper， the effect of a single-opening split-ring resonator （SRR） structure on the performance of ultra-wideband （UWB） microstrip patch antenna （MPA） is studied. Here a UWB MPA based on partial grounding is proposed， and the SRR structure is utilized to optimize other characteristics of the low-profile microstrip antenna while ensuring the bandwidth and gain remain unchanged. The proposed metamaterial structure， consisting of a 2 × 2 array of SRR， is loaded on the reverse side of the substrate. The volume of the proposed antenna is 61.6×67.6×1.5mm3. According to simulation and experimental results， the proposed microstrip antenna loaded with 2×2 SRRs performs better than that without SRR structure. It produces an operating band of 1.62 GHz-8 GHz while achieving circular polarization characteristics with an axial ratio （AR） bandwidth of 3.92 GHz-4.57 GHz. In addition， the performance of the proposed antenna is superior to relevant works of literature The antenna can be widely utilized in wireless communication systems.

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Getting physical with medical education:Exercise based virtual anatomy review classes for medical students

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World Journal of Methodology 2025年第1期15卷 20-25页

作者： Nadeesha R Samarasinghe Taniya S Nagpal Michele l Barbeau Charys M Martin Division of General Surgery Faculty of MedicineUniversity of British ColumbiaVancouver V6T 1Z3BCCanada Faculty of Kinesiology Sport and RecreationUniversity of AlbertaEdmonton T6G 2R3ABCanada Anatomy and Cell Biology University of Western OntarioLondon N6A 3K7ONCanada Department of Anatomy and Cell Biology Schulich School of Medicine and DentistryThe University of Western OntarioLondon N6A 3K7ONCanada

The benefits of regular physical activity are well ***,few studies have examined the effectiveness of integrating physical activity(PA)into curricula within a post-secondary *** investigate the incorporation of PA into medical curriculum,we developed a series of optional exercise-based review sessions designed to reinforce musculoskeletal(MSK)anatomy course *** synchronous sessions were co-taught by a group fitness instructor and an anatomy *** fitness instructor would lead students through both strength and yoga style exercises,while the anatomy instructor asked questions about relevant anatomical structures related to course material previously *** the sessions,participants were asked to evaluate the classes on their self-reported exam preparedness in improving MSK anatomy knowledge,PA levels,and mental *** participants completed surveys;a majority agreed that the classes increased understanding of MSK concepts(90.0%)and activity levels(97.7%).Many(70.0%)felt that the classes helped reduce *** majority of respondents(90.0%)agreed that the classes contributed to increased feelings of social ***,medical students saw benefit in PA based interventions to supplement MSK course *** with increasing activity levels and promoting health behaviours,integrating PA into medical curriculum may improve comprehension of learning material,alleviate stress and foster social connectivity among medical students.

关键词： Medical education Musculoskeletal Anatomy Exercise Online learning

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