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World journal of Gastroenterology 2014年第30期20卷 10620-10627页

作者： j.hn m rivas Alejro Perez marlow Hernez Alison Schneider Ferno j Castro Digestive Disease Center Cleveland Clinic FloridaWestonFL 33331United States Department of Gastroenterology University of Medicine and Dentistry of New JerseyStratfordNJ 08084United States Department of Internal medicine Cleveland Clinic FloridaWestonFL 33331United States

AIm: To compare the bowel cleansing efficacy of same day ingestion of 4-L sulfa-free polyethylene glycol (4-L SF-PEG) vs 2-L polyethylene glycol solution with ascorbic acid (2-L PEG + Asc) in patients undergoing after... 详细信息

关键词： Bowel preparation Colonoscopy Screening colonoscopy Colon cancer screening

Phase separation and coarsening of NiAl(β′)intermetallic in quench-aged Fe-Ni-Al alloys

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journal of Iron and Steel Research International 2020年第11期27卷 1331-1338页

作者： C.Ferreira-Palma j.A.Rosas-Barrios V.m.Lopez-Hirata D.I.rivas-Lopez H.j.Dorantes-Rosales Faculty of Chemical Sciences Universidad VeracruzanaVeracruz 94294Mexico ESIQIE Instituto Politecnico Nacional.UPALMMexico City 07738Mexico

The coarsening behavior of four quench-aged Fe-Ni-AI alloys with different Ni and Al con tents is *** alloys were solubilized at 1100℃for 24 h,water-quenched and aged at 850℃for periods ranging from 1 to 100 h to promote phase separation and *** two alloys with the highest combined Ni and Al contents(>35 at.%)showed signs of spinodal decomposition,while the alloys with lower Ni and Al contents followed a classical nucleation *** Ni and Al contents promoted an increase in NiAl(β′)phase fraction in concordance with phase equilibrium *** alloy with the highest[3'fraction presented a completely interconnected *** coarsening ofβ′particles in the other three alloys followed the predictions of the Lifshitz-Slyozov-Wagner(LSW)*** general trend was an increase in the coarsening kinetics with higher Ni and Al *** highest hardness was found in the alloys with higher fraction albeit these compositions are less resistant to coarsening and have been reported to present a low room-temperature ductility.

关键词： Precipitation Spinodal decomposition Coarsening Aging Fe-Ni-Al alloy

Patch isolation and shape predict plant functional diversity in a naturally fragmented forest

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journal of Plant Ecology 2018年第1期11卷 136-146页

作者： Amaranta Arellano-rivas j.Arturo De-Nova miguel A.munguía-Rosas Instituto de Investigación de Zonas Desérticas Universidad Autónoma de San Luís PotosíSan Luis Potosí78377México Laboratorio de Ecología Terrestre Departamento de Ecología HumanaCentro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional(CINVESTAV)Mérida 97310México Facultad de Agronomía Universidad Autónoma de San Luís PotosíSan Luis Potosí78321México

Aims It is known that taxonomic diversity can be predicted by the spatial configuration of the habitat,in particular by its area and degree of ***,taxonomic diversity is a poor predictor of ecosystem *** functional diversity is strongly linked to the func-tionality and stability of ecosystems,little is known about how changes in the spatial configuration of the habitat affect functional *** this study,we evaluated whether the spatial configuration of forest patches predicts the functional diversity of plants in a fragmented *** Five functional leaf traits(leaf dry matter content,leaf punch force,specific leaf area,leaf size and leaf thickness)were measured for 23 dominant plant species in 20 forest patches in a naturally fragmented forest on the yucatan ***-weighted multivariate and individual trait metrics of functional diversity were calculated and cor-related with size,degree of isolation and the shape of forest *** Findings Patch shape was negatively correlated with multivariate and individ-ual trait(leaf dry matter content and leaf size)metrics of functional *** isolation measures were also negatively correlated with individual trait(leaf dry matter content,leaf punch force and leaf size)metrics of functional *** other words,greater patch shape irregularity and isolation degree impoverish plant func-tional *** is the first report of the negative effects of patch shape irregularity and isolation on the functional diversity of plant communities in a forest that has been fragmented for a long time.

关键词： forest fragmentation functional diversity habitat spatial configuration petenes yucatan

Bio-inspired tetracarbene compounds as a new family of energy saving catalysts

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journal of Energy Chemistry 2023年第4期79卷 559-561页

作者： Bo Zhang Fritz E.Kühn CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina' University of Chinese Academy of Science Beijing 100049China molecular Catalysis Catalysis Research Center and Department of ChemistrySchool of Natural SciencesTechnical University of MunichLichtenbergstr 485748 Garching bei MünchenGermany

Efficient use of energy is a pressing *** of chemical processes is currently an important target for energy *** chemical processes are independent of pathways with respect to the final energy output or consumption,the application of catalysts can reduce involved activation energies considerably and therefore save large amounts of energy.

关键词： Catalysis Iron Carbenes multidentate ligands

Sampling duration and freezing temperature influence the analysed gastric inositol phosphate composition of pigs fed diets with different levels of phytase

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Animal Nutrition 2019年第2期5卷 196-201页

作者： Steven Laird Imke Kühn michael R.Bedford Hayley Whitfield Helen m.miller Faculty of Biological Sciences University of Leeds AB Vista School of Biological Sciences University of East Anglia

This experiment was conducted to determine the effects of time and freezing temperature during sampling on gastric phytate(myo-inositol [mYO] hexakisphosphate [InsP6]), lower inositol phosphates(InsP2-5) and mYO concentrations in pigs fed diets containing different levels of phytase. Forty pigs were fed 1 of 4 wheat-barley diets on an ad libitum basis for 28 d. The diets comprised a nutritionally adequate positive control(PC), a similar diet but with Ca and P reduced by 1.6 and 1.24 g/kg, respectively(NC), and the NC supplemented with 500(NC + 500) or 2,000(NC + 2000) FTU phytase/kg. At the end of the experiment, chyme were collected from the stomach, thoroughly mixed and 2 subsamples(30 mL) were frozen immediately: one snap-frozen at-79 ℃ and the other at-20 0 C. The remaining chyme were left to sit at room temperature(20 ℃) and further subsamples were collected and frozen as above at 5,10 and15 min from the point of mixing. There were linear reductions in gastric InsP6 concentration over time during sampling(P mperature. moreover, InsP6 concentration was influenced by a diet × freezing temperature interaction(P measured in chyme frozen at-20 ℃ than at-79 ℃;however,this difference was greater in the control diets than the phytase supplemented diets. Freezing chyme at-79 ℃ recovered more ∑InsP2-5 + mYO than freezing at-20 ℃ in pigs fed phytase supplemented diets;however, this difference was not apparent in the diets without phytase(diet × freezing temperature, P me of pigs during sampling and processing, irrespective of supplementary phytase activity. Therefore, to minimise post-slaughter phytate degradation and changes in the gastric inositol phosphate profile, chyme should be snap-frozen immediately after collection.

关键词： Pig Inositol phosphate Phytase Sampling time Freezing temperature

Compositional complexity dependence of dislocation density and mechanical properties in high entropy alloy systems

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Progress in Natural Science:materials International 2020年第4期30卷 545-551页

作者： P.Thirathipviwat G.Song j.Bednarcik U.Kühn T.Gemming K.Nielsch j.Han Leibniz Institute of Solid State and materials Research (IFW Dresden) Frontier Research Center for Applied Atomic Sciences Ibaraki University Division of Advanced materials Engineering and Institute for rare metals Kongju National University Institute of Physic Pavol Jozef Safarik University in Ko?ice Deutsches Elektronen-Synchrotron (DESY) Institute of materials Science Technische Universit?t Dresden Institute of Applied Physics Technische Universit?t Dresden Korea Institute for Rare metals Korea Institute of Industrial Technology (KITECH)

This study focuses on a quantitative analysis of dislocation accumulation after cold plastic deformation and mechanical properties of Fe Ni Co Cr mn and Ti Nb Hf Ta Zr high entropy alloys(HEAs) which are single phase fcc and bcc solid solutions, respectively. In order to study the role of compositional complexity from unary to quinary compositions on dislocation accumulation and mechanical properties after plastic deformation, the single solid solution phase forming sub-alloys of the two HEAs were investigated. All studied samples revealed a large plastic deformability under cold-rotary swaging process by 85–90% area reduction without intermediate annealing. The dislocation density of all studied samples, determined by Williamson-Hall method on synchrotron X-ray diffraction patterns, were between 1014-1015m-2dependent on the alloy composition. The level of dislocation density after plastic deformation is not only affected by the number of constituent element but the lattice distortion and intrinsic properties in terms of stacking fault energy, modulus misfit, and melting point also impact the dislocation storage. The level of dislocation density determines the level of mechanical properties because of a resistance to dislocation motions. The hardness and yield compressive strength of the studied samples are proportional to the level of dislocation density.

关键词： High entropy alloys Dislocation density Synchrotron XRD mechanical properties

Fibroblast growth factor(FGF)signaling in development and skeletal diseases

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Genes & Diseases 2014年第2期1卷 199-213页

作者： Chad m.Teven Evan m.Farina jane rivas Russell R.Reid The Laboratory of Craniofacial Biology Section of Plastic&Reconstructive SurgeryDepartment of SurgeryThe University of Chicago Medical Center5841 South Maryland AvenueMC 6035ChicagoIL 60637USA The University of Chicago Pritzker School of medicine ChicagoIL 60637USA

Fibroblast growth factors(FGF)and their receptors serve many functions in both the developing and adult *** contain 18 FGF ligands and four FGF receptors(FGFR).FGF ligands are polypeptide growth factors that regulate several developmental processes including cellular proliferation,differentiation,and migration,morphogenesis,and ***-FGFR signaling is also critical to the developing axial and craniofacial *** particular,the signaling cascade has been implicated in intramembranous ossification of cranial bones as well as cranial suture *** the adult,FGFs and FGFRs are crucial for tissue *** signaling generally follows one of three transduction pathways:RAS/mAP kinase,PI3/AKT,or *** pathway likely regulates specific cellular *** expression of FGF and improper activation of FGFRs are associated with various pathologic conditions,unregulated cell growth,and ***,aberrant signaling has been implicated in many skeletal abnormalities including achondroplasia and *** biology and mechanisms of the FGF family have been the subject of significant research over the past 30 ***,work has focused on the therapeutic targeting and potential of FGF ligands and their associated *** majority of FGF-related therapy is aimed at age-related *** understanding of FGF signaling and biology may reveal additional therapeutic roles,both in utero and *** review discusses the role of FGF signaling in general physiologic and pathologic embryogenesis and further explores it within the context of skeletal development.

关键词： Craniosynostosis FGF signaling Fibroblast growth factor Fibroblast growth factor receptor Genetics Pathogenesis Signal transduction Skeletal development

No relationship between biopsy sites near the main testicular vessels or rete testis and successful sperm retrieval using conventional or microdissection biopsies in 220 non-obstructive azoospermic men

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Asian journal of Andrology 2013年第6期15卷 795-798,I0009页

作者： j Ullrich Schwarzer Heiko Steinfatt Heiko Steinfatt manfred Schleyer Frank m Kōhn Klaus Fiedler2, Irene von Hertwig Gottfried Krüsmann Wolfgang Würfel Andrologie Centrum mOnchen MOnchen D-81241 Germany Kinderwunsch Centrum mOnchen MOnchen D-81241 Germany Andrologicum mOnchen MOnchen D-80331 Germany

In 220 consecutive patients with non-obstructive azoospermia, sperm retrieval was attempted by a combination of conventional and microdissection testicular sperm extraction （TESE）. For sperm retrieval, 2-3 conventional biopsies were performed followed by a microdissection TESE in cases of negative conventional biopsies. During the surgery, the vasculature of the testis was assessed using the operative microscope, and the location of positive biopsies was registered in relation to the blood supply. The overall sperm retrieval rate was 58.2%. From the initial conventional biopsies, sperm could be retrieved in 46.8% of the patients. With microdissection TESE, sperm could be retrieved from an additional 11.4% of the patients. The further use of microdissection TESE improved the sperm retrieval rate significantly （P=0.017）. No significant accumulation of positive biopsies was found towards the rete testis or the main testicular vessels.

关键词： intracytoplasmic sperm injection male infertility microdissection testicular sperm extraction non-obstructiveazoospermia sperm retrieval

Assessing above-ground biomass-functional diversity relationships in temperate forests in northern mexico

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Forest Ecosystems 2021年第1期8卷 95-108页

作者： Benedicto Vargas-Larreta jorge Omar López-martínez Edgar j.González joséjavier Corral-rivas Francisco javier Hernández Tecnológico Nacional de méxico/Instituto Tecnológico de El Salto 34942 El SaltoDurangoMexico Cátedras CONACYT1582Av.Insurgentes SurCiudad de MéxicoMexico El Colegio de la Frontera Sur 77014ChetumalQuintana RooMexico Departamento de Ecología y Recursos Naturales Facultad de CienciasUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoMexico Facultad de Ciencias Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.Durango s/nCol.Valle del Sur34120 DurangoMexico

Background:Studies on the relationship between biodiversity and ecosystem productivity have suggested that species richness and functional diversity are the main drivers of ecosystem *** patterns on this relationship have been found,including positive,unimodal,negative,and neutral trends,keeping the issue *** this study,taxonomic diversity and functional diversity as drivers of above-ground biomass(AGB)were compared,and the mechanisms that influence biomass production were investigated by testing the complementarity and the mass-ratio ***:Using data from 414 permanent sample plots,covering 23%of temperate forest in the Sierra madre Oriental(méxico),we estimated the above-gound biomass(AGB),taxonomic and functional diversity indices,as well as community weighted mean values(CWm)for three functional traits(maximum height,leaf size and wood density)for trees≥7.5 cm DBH,in managed and unmanaged *** compare taxonomic diversity differences between managed and unmanaged stands we carried out a rarefaction ***,we evaluated the relationship between AGB and taxonomic and functional diversity metrics,as well as CWm traits throught spatial autoregressive ***:We found a hump-shaped relationship between AGB and species richness in managed and unmanaged *** of maximum height was the most important predictor of AGB in both stands,which suggested that the mechanism underlaying the AGB-diversity relationship is the dominance of some highly productive species,supporting the mass-ratio ***-ground biomass was significantly correlated with three of the five functional diversity metrics,CWm maximum height and species *** results show the importance of taking into account spatial autocorrelation in the construction of predictive models to avoid spurious patterns in the AGBdiversity ***:Species richness,maximum height,functional richness,functional dispersion and Rao

关键词： Taxonomic diversity Functional diversity Complementarity hypothesis mass-ratio hypothesis

Grouping tree species to estimate basal area increment in temperate multispecies forests in Durango,mexico

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Forest Ecosystems 2024年第1期11卷 1-13页

作者： jaime Roberto Padilla-martínez Carola Paul Kai Husmann jose javier Corral-rivas Klaus von Gadow Department of Forest Economics and Sustainable Land-use Planning Faculty of Forest Sciences and Forest EcologyUniversity of GottingenBüsgenweg 137077GottingenGermany Facultad de Ciencias Forestales Universidad Juarez del Estado de DurangoRío Papaloapan y Boulevard Durango S/N34120DurangoMexico Faculty of Forestry and Forest Ecology Georg-August-UniversitatBüsgenweg 537077GottingenGermany Department of Forestry and Wood Science Faculty of AgriSciencesStellenbosch UniversityStellenbosch Private Bag X1Stellenbosch7602South Africa

multispecies forests have received increased scientific attention,driven by the hypothesis that biodiversity improves ecological ***,a greater species diversity presents challenges for forest management and *** study aims to develop basal area growth models for tree species *** analysis is based on a dataset of 423 permanent plots(2,500 m^(2))located in temperate forests in Durango,***,we define tree species cohorts based on individual and neighborhood-based variables using a combination of principal component and cluster ***,we estimate the basal area increment of each cohort through the generalized additive model to describe the effect of tree size,competition,stand density and site *** principal component and cluster analyses assign a total of 37 tree species to eight cohorts that differed primarily with regard to the distribution of tree size and vertical position within the *** generalized additive models provide satisfactory estimates of tree growth for the species cohorts,explaining between 19 and 53 percent of the total variation of basal area increment,and highlight the following results:i)most cohorts show a"rise-and-fall"effect of tree size on tree growth;ii)surprisingly,the competition index"basal area of larger trees"had showed a positive effect in four of the eight cohorts;iii)stand density had a negative effect on basal area increment,though the effect was minor in medium-and high-density stands,and iv)basal area growth was positively correlated with site quality except for an oak *** developed species cohorts and growth models provide insight into their particular ecological features and growth patterns that may support the development of sustainable management strategies for temperate multispecies forests.

关键词： Temperate multispecies forests Cluster analysis Basal area increment Generalized additive models