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A revised generic classification of the jelly lichens, Collemataceae

Fungal Diversity 2014年第1期64卷 275-293页

作者： mónica A.G.Otálora per m.jørgensen mats Wedin Department of Botany Swedish Museum of Natural HistoryP.O.Box 50007SE-10405 StockholmSweden Department of Natural History Bergen University MuseumAllégt.41Box 78005020 BergenNorway

Phylogenetic studies have shown the need for a revised circumscription of generic boundaries in the jelly lichens(Collemataceae).Using a four-marker dataset from a recently published phylogeny of Collemataceae,we tested the monophyly of ten morphologically well-characterized *** achieve this,we performed Bayesian and maximum likelihood *** monophyly of the ten morphological groups was *** order to reconcile molecular and morphological data into a formal classification,we here propose new generic delimitations in *** and Leptogium are re-circumscribed and six old generic names are resurrected to accommodate the Collema Crispum-group(Blennothallia),the Collema Tenax-group(Enchylium),the Collema Cristatum-group(Lathagrium),the Collema Occultatum-group(Rostania),the former small Leptogium species(Scytinium),and Leptogium diffractum(Pseudoleptogium).In addition,two new genera are described to accommodate Collema multipartitum(Callome)and the Collema Italicum-group(Paracollema).The presence/absence of a eucortex,which was earlier used as the cardinal character to define genera in the family,is still useful,but only in combination with other traits such as thallus habit(size),lobe size,ascospore characteristics,thallus anatomical structure,and habitat preference.A key to the genera is *** are designated for Collema marginale Hoffm.,Synechoblastus nigrescens(Huds.)Trevis.,Eucollema(Cromb.)Horw.,Collema section Enchylium Ach.,Collema section Lathagrium Ach.,Collema *** Ach.,Collema section Scytinium Ach.,Collemodium *** Lamy,and Homodium *** Olivier.

关键词： Classification Collemataceae Cyanolichens jelly lichens Test of monophyly

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BOUNDARY PROCEDURES FOR THE TImE-DEPENDENT BURGERS' EQUATION UNDER UNCERTAINTY

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Acta mathematica Scientia 2010年第2期30卷 539-550页

作者： per Pettersson jan Nordstrm Gianluca Iaccarino mechanical Engineering and Institute for Computational mathematical Engineering Stanford University Division of Scientific Computing Department of Information TechnologyUppsala University School of mechanical Industrial and Aeronautical EngineeringUniversity of the Witvatersrand Department of Aeronautics and Systems Integration FOIThe Swedish Defense Research Agency

The Burgers＇ equation with uncertain initial and boundary conditions is approximated using a Polynomial Chaos Expansion （PCE） approach where the solution is represented as a series of stochastic, orthogonal polynomials. The resulting truncated PCE system is solved using a novel numerical discretization method based on spatial derivative operators satisfying the summation by parts property and weak boundary conditions to ensure stability. The resulting PCE solution yields an accurate quantitative description of the stochastic evolution of the system, provided that appropriate boundary conditions are available. The specification of the boundary data is shown to influence the solution; we will discuss the problematic implications of the lack of precisely characterized boundary data and possible ways of imposing stable and accurate boundary conditions.

关键词： stochastic Burgers' equation uncertainty quantification polynomial chaos

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Laparoscopic distal pancreatectomy for adenocarcinoma of the pancreas

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World journal of Gastroenterology 2014年第37期20卷 13402-13411页

作者： Bergthor Bjrnsson per Sandstrm Department of Surgery County Council of stergtland and Department of Clinical and Experimental MedicineFaculty of Health SciencesLinkping University

Since the first report on laparoscopic distal pancreatectomy (LDP) appeared in the 1990s, the procedure has been performed increasingly frequently to treat both benign and malignant lesions of the pancreas. many earlier publications have shown LDP to be a good alternative to open distal pancreatectomy for benign lesions, although this has never been studied in a prospective, randomized manner. The evidence for the use of LDP to treat adenocarcinoma of the pancreas is not as well established. The purpose of this review is to evaluate the current evidence for LDP in cases of pancreatic adenocarcinoma. We conducted a review of English language publications reporting LDP results between 1990 and 2013. All studies reporting results in patients with histologically proven pancreatic adenocarcinoma were included. Thirty-nine publications were found and included in the results for a total of 309 cases of pancreatic adenocarcinoma (potential double publications were not eliminated). most LDP procedures are performed in selected cases and generally involve smaller tumors than open distal pancreatectomy (ODP) procedures. Some of the papers report unselected cases and include procedures on larger tumors. The number of lymph nodes harvested using LDP is comparable to the number obtained with ODP, as is the frequency of R0 resections. Current data suggest that similar short term oncological results can be obtained using LDP as those obtained using ODP.

关键词： Adenocarcinoma of the pancreas Laparoscopy Distal pancreatectomy Surgical margins Pancreatic resection

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A comparison of lower limb stiffness and mechanical muscle function in ACL-reconstructed,elite,and adolescent alpine ski racers/ski cross athletes

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journal of Sport and Health Science 2018年第4期7卷 416-424页

作者： matthew j.jordan per Aagaard Walter Herzog Canadian Sport Institute Calgary Calgary AB T2N IN4Canada Department of Sports Science and Clinical Biomechanics SDU Muscle Research ClusterUniversity of Southern DenmarkOdense DK-5230Denmark Human performance Laboratory University of CalgaryCalgaryAB T2N IN4Canada Corresponding author.E-mail address： mjordan@ucalgary.ca

Purpose： The aim of this study was to compare mechanical muscle function in the eccentric/concentric phases of vertical bilateral jumping in anterior cruciate ligament-reconstructed （ACLR）, elite （ELITE）, and adolescent （ADOL） alpine ski racers and ski cross athletes. methods： Alpine ski racers/ski crossers （ACLR： n = 12, age = 26.7 ± 3.8 years; ELITE： n = 12, age = 23.9 ± 3.0 years; ADOL： n = 12, age = 17.8 ± 0.7 years; females： n = 6 per group, males： n = 6 per group） performed 5 maximal countermovement jumps （Cmjs） and 5 squat jumps. The ground reaction forces for each limb were analyzed using dual force plate recording to obtain body center of mass （BCm） velocity, displacement, and power. The eccentric deceleration （ECC） and concentric phases were determined from BCm velocity. Cmj net concentric and ECC impulses were calculated （body mass normalized） along with the peak and mean BCm power and maximal vertical jump height. Cmj lower limb stiffness （LLS） was determined by the slope of the ground reaction forces vs. the BCm displacement curve over the ECC phase. Concentric and ECC asymmetry indices were calculated for each leg, and the left vs. right LLS was compared. Outcome measures （reported as mean ± SD） calculated as a 5-jump mean were normalized to body mass and compared using an analysis of variance. Results： No between-group differences were found for peak and mean power or jump heights. There were no group differences for LLS or net concentric phase impulse, but the net ECC impulse was lower in the ADOL group compared with ELITE skiers （ADOL： 1.33 ± 0.32 Ns/kg; ELITE： 1.59 ± 0.16 Ns/kg; p 〈 0.05）. Although no group differences were found for ECC asymmetry indices, a group × limb interaction was found for LLS （p 〈 0.01）, which was systematically higher in the right vs. the left limb of ADOL skiers （right： 54.1 ± 17.9 N/m/kg; left： 48.7 ± 15.7 N/m/kg;p 〈 0.01）. Conclusion： ADOL skiers demonstrated decreased ECC impulse and systematic right limb dominance in

关键词： Between-limb asymmetry Injury prevention Knee injuries muscle power Vertical jump

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A direct solver with O（N） complexity for integral equations on one-dimensional domains

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Frontiers of mathematics in China 2012年第2期7卷 217-247页

作者： Adrianna GILLmAN Patrick m. YOUNG per-Gunnar mARTINSSON Department of Applied mathematics University of Colorado at Boulder BoulderCO 80309-0526 USA

An algorithm for the direct inversion of the linear systems arising from NystrSm discretization of integral equations on one-dimensional domains is described. The method typically has O（N） complexity when applied to boundary integral equations （BIEs） in the plane with non-oscillatory kernels such as those associated with the Laplace and Stokes＇ equations. The scaling coefficient suppressed by the ＂big-O＂ notation depends logarithraically on the requested accuracy. The method can also be applied to BIEs with oscillatory kernels such as those associated with the Helmholtz and time-harmonic maxwell equations; it is efficient at long and intermediate wave-lengths, but will eventually become prohibitively slow as the wave-length decreases. To achieve linear complexity, rank： deficiencies in the off-diagonal blocks of the coefficient matrix are exploited. The technique is conceptually related to the H- and H2-matrix arithmetic of Hackbusch and coworkers, and is closely related to previous work on Hierarchically Semi-Separable matrices.

关键词： Direct solver integral equation fast direct solver boundary value problem boundary integral equation hierarchically semi-separable matrix mSC 65R20,65F05

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Comparative analysis of planted and unplanted controls for assessment of rhizosphere priming effect

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Pedosphere 2022年第6期32卷 884-892页

作者： jian LI per BENGTSON Department of Biology Microbial Ecology GroupLund UniversitySölvegatan 37Lund 22362(Sweden) Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of Sciences1799 Jimei RoadXiamen 361021(China)

The rhizosphere priming effect(RPE)is increasingly being considered to be an important regulator of soil organic matter(SOm)decomposition and nutrient turnover,with potential importance for the global CO_(2) *** a result,studies on the RPE have rapidly increased in number over the last few *** of these experiments have been performed using unplanted soil as the control,which could potentially lead to incorrect assessment of the ***,we performed a greenhouse experiment to investigate how the choice of control(i.e.,unplanted control and planted control)influenced the quantification of RPE on SOm decomposition and gross nitrogen(N)mineralization,and to link this to differences in microbial and abiotic soil properties between the two *** the planted control,planted seedlings were cut at soil surface 5 d before measurement of the *** RPE on SOm decomposition was positive in pine soil and almost 2-fold higher when calculated from the planted control than from the unplanted *** spruce soil,a negative RPE on SOm decomposition was found when calculated from the planted control,while the RPE was positive when calculated from the unplanted *** RPE on gross N mineralization was found when calculated from the planted control,while a positive RPE of more than 100%was found when calculated from the unplanted *** microbial biomass and growth rate were lower,while the inorganic N content was higher in the unplanted control than in the planted *** microbial community composition and potential enzyme activity in the planted treatment and planted control were similar,but they differed significantly from those in the unplanted *** results showed that the RPE varied widely depending on the choice of control;thus,we suggest that a planted control,in which the aboveground plant parts are removed only a few days before the measurement of RPE,should be used as the control when elucidating the RPE on belowground C and N

关键词： enzyme activity gross nitrogen mineralization microbial community composition nitrogen availability soil organic matter decomposition

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The potential drivers in forming avian biodiversity hotspots in the East Himalaya mountains of Southwest China

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Integrative Zoology 2015年第2期10卷 171-181页

作者： Fumin LEI Yanhua QU Gang SONG per ALSTRÖm.jon FjELDSÅ Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijingChina Swedish Species Information Centre Swedish University of Agricultural SciencesUppsalaSweden Centre of macroecology Evolution and ClimateZoological MuseumUniversity of CopenhagenCopenhagenDenmark

Little has been published to describe or interpret Asian biodiversity hotspots,including those in the East Himalayan mountains of Southwest China(HmSC),thus making necessary a review of the current *** Pliocene and Pleistocene geological and glacial histories of the Asian continent differ from those of Europe and North America,suggesting different mechanisms of speciation and extinction,and,thus,different responses to climate changes during the Quaternary *** short review summarizes potential drivers in shaping and maintaining high species richness and endemism of birds in the *** geographical location at the junction of different biogeographical realms,the wide range of habitats and climates along the extensive elevational range,the complex topography and the distinct geological history of this region have probably contributed to the evolution of an exceptionally species-rich and endemic-rich,specialized montane avian *** mountain systems in the HmSC may have provided refugia where species survived during the glacial periods and barriers for preventing species dispersal after the glacial *** studies are required to further test this refugia hypothesis by comparing more cold-tolerent and warm-tolerent species.

关键词： biodiversity hotspots East Himalayan mountains of Southwest China phylogeographical divergence Pleistocene glaciations species richness and endemism

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Factors shaping community structure of endophytic fungi–evidence from the Pinus-Viscum-system

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Fungal Diversity 2013年第3期60卷 55-69页

作者： Derek peršoh Systematische Botanik und mykologie Ludwigs-Maximilians Universität MünchenMenzinger Straße 6780638 MünchenGermany Abteilung mykologie Universität BayreuthUniversitätsstraße 30–NW I95440 BayreuthGermany

Endophytic fungal communities have been shown to be highly diverse in almost every host plant species analyzed so ***,the factors shaping their compositions are largely *** elucidate the impact of various factors,10 independent replicates of DNA extracts from each of 17 surface-sterilized leaf and stem samples were analyzed by pyrosequencing of fungal ITS1 rRNA gene ***,154 fungal OTUs(operational taxonomic units),represented by 953,385 sequences,were found in at least 2 samples from Viscum album *** and/or its host Pinus *** from earlier,cultivation-based assessments,the communities were dominated by OTUs related to the genus mortierella and OTUs not assignable to a certain fungal ***,Ascomycota were still the most diverse group in terms of OTU richness and already hypothesized organ and host preferences of certain endophytic Xylariaceae isolated from the Pinus-Viscum-system could be *** species and organ type were also the m.jor factors shaping the detected fungal *** two plant species clearly differed according to the endophytic fungal communities,but only stems and needles of Pinus were inhabited by significantly different fungal ***,only the 1 and 3 year old stem sections differed according to the endophytic fungal community,while differently aged leaves of both plants were indistinguishable in this *** of the organs had no impact on fungal communities in Pinus,but shorter internodes and smaller leaves showed at least a tendency to differ from the corresponding larger organs in *** communities also differed slightly between the two sampling sites,lying 200 km apart,and between the three sampling *** the samples were drawn within 15 days,this finding indicates that seasonal shifts clearly outweigh aging effects in host plant with perennial *** results therefore provide strong evidence against a linear developm

关键词： Endophytic fungi Pyrosequencing Host preference Stems Leaves Organ age Pinus sylvestris Viscum album Genetic abundance Name assignment

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microstructural evaluation and nanohardness of an AlCoCuCrFeNiTi high-entropy alloy

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International journal of minerals,metallurgy and materials 2019年第5期26卷 634-641页

作者： C.D.Gómez-Esparza R.peréz-Bustamante j.m.Alvarado-Orozco j.mu?oz-Salda?a R.martínez-Sánchez j.m.Olivares-Ramírez A.Duarte-moller Centro de Investigación en materiales Avanzados (CImAV) Laboratorio Nacional de Nanotecnología CONACYT-Corporación mexicana de Investigación en materiales S.A.de C.V.(COmImSA) Centro de Ingeniería y Desarrollo Industrial Querétaro Campus Centro de Investigación y de Estudios Avanzados del IPN Unidad Querétaro Universidad Tecnológica de San juan del Río Escuela de Ingeniería Civil Industrialy Mecánica Universidad De La Salle Bajío

An AlCoCuCrFeNiTi high-entropy alloy(HEA) was prepared by mechanical alloying and sintering to study the effect of Ti addition to the widely studied AlCoCuCrFeNi system. The structural and microstructural characteristics were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEm), and transmission electron microscopy(TEm). The formation of four micrometric phases was detected: a Cu-rich phase with a face-centered cubic(fcc) structure, a body-centered cubic(bcc) solid solution with Cu-rich plate-like precipitates(fcc), an ordered bcc phase, and a tetragonal structure. The XRD patterns corroborate the presence of a mixture of bcc-, fcc-, and tetragonal-structured phases. The Vickers hardness of the alloy under study was more than twice that of the AlCoCuCrFeNi alloy. Nanoindentation tests were performed to evaluate the mechanical response of the individual phases to elucidate the relationship between chemical composition, crystal structure, and mechanical performance of the multiphase microstructure of the AlCoCuCrFeNiTi HEA.

关键词： high-entropy alloys mechanical alloying microstructure nanoindentation

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Nitrite,a novel method to decrease ischemia/reperfusion injury in the rat liver

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World journal of Gastroenterology 2015年第6期21卷 1775-1783页

作者： Bergthor Bjrnsson Linda Bojmar Hans Olsson Tommy Sundqvist per Sandstrm Department of Surgery County Council of ?sterg?tland Department of Clinical and Experimental medicine Faculty of Health Sciences Link?ping University Department of Pathology County Council of ?sterg?tland

AIm:To investigate whether nitrite administered prior to ischemia/reperfusion(I/R)reduces liver ***:Thirty-six male Sprague-Dawley rats were randomized to 3 groups,including sham operated(n=8),45-min segmental ischemia of the left liver lobe(IR,n=14)and ischemia/reperfusion(I/R)preceded by the administration of 480 nmol of nitrite(n=14).Serum transaminases were measured after 4 h of *** microdialysate(mD)was sampled in 30-min intervals and analyzed for glucose,lactate,pyruvate and glycerol as well as the total nitrite and nitrate(NOx).The NOx was measured in ***:Aspartate aminotransferase(AST)at the end of reperfusion was higher in the IR group than in the nitrite group(40±6.8μkat/L vs 22±2.6μkat/L,P=0.022).Similarly,alanine aminotransferase(ALT)was also higher in the I/R group than in the nitrite group(34±6μkat vs 14±1.5μkat,P=0.0045).The NOx in mD was significantly higher in the nitrite group than in the I/R group(10.1±2.9μmol/L vs 3.2±0.9μmol/L,P=0.031)after the administration of *** ischemia,the levels decreased in both groups and then increased again during *** the end of reperfusion,there was a tendency towards a higher NOx in the I/R group than in the nitrite group(11.6±0.7μmol/L vs 9.2±1.1μmol/L,P=0.067).Lactate in mD was significantly higher in the IR group than in the nitrite group(3.37±0.18 mmol/L vs 2.8±0.12 mmol/L,P=0.01)during ischemia and the first 30 min of *** the same period,glycerol was also higher in the IRI group than in the nitrite group(464±38μmol/L vs 367±31μmol/L,P=0.049).With respect to histology,there were more signs of tissue damage in the I/R group than in the nitrite group,and29%of the animals in the I/R group exhibited necrosis compared with none in the nitrite *** nitric oxide synthase transcription increased between early ischemia(t=15)and the end of reperfusion in both ***:Nitrite administered before liver ischemia in the rat liver redu

关键词： Ischemia-reperfusion injury Nitrite Liver ischemia

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