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Stand structure and productivity of Populus euphratica along a gradient of groundwater distances at the tarim River(NW china)

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Journal of Plant Ecology 2017年第5期10卷 753-764页

作者： Frank M.Thomas michael jeschke Ximing Zhang Petra Lang Geobotany Faculty of Regional and Environmental SciencesUniversity of TrierBehringstraße 2154296 TrierGermany Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences40 South Beijing Road830011 UrumqiChina

Aims Along central-Asian rivers in arid regions,lowering of the ground-water level constitutes a major threat to the riparian forests,whose tree layers are dominated by Euphrates poplar(Populus euphratica).Some of these fragile ecosystems are supplied with additional(‘eco-logical’)water for protection and conservation.We investigated interrelationships among groundwater distance,stand structure and above-ground wood production(at the tree and the stand level)in P.euphratica stands along a groundwater gradient(distances of 2.0-12.0 m)that also included a plot supplied with‘ecological water’.Methods We measured the height,diameter at breast height and basal area of poplar trees and determined the annual above-ground wood production for the three most recent years on the basis of tree-ring analyses and allometric regressions at three sites at the upper,mid-dle and lower reaches of the tarim River,Xinjiang,NW china.Important Findingsthe distribution of age classes differed significantly among the plots:in accordance with their life histories,stands growing at a larger distance to the groundwater harboured a larger fraction of old trees(>80 years)and,in most cases,a smaller fraction of young trees(≤20 years).the annual above-ground wood production per ha was highest on a plot with a short groundwater distance(2.0 m;maxi-mum of the 3-year investigation period:3.0 t ha−1 a−1)and lowest,at a plot with a large distance to the water table(6.6 m;minimum:0.23 t ha^(−1)a^(−1)).However,the plot located close to the groundwater(and to the river)at the middle reaches exhibited a relatively large interannual variation in above-ground wood production,which can be attributed to interannual variations in the river discharge.At the middle and the lower reaches,these interannual variations on plots with the most favourable water supply were even more obvious at the tree level.For the fraction of mature trees(60-99 years old),no significant differences in above-ground wood production were found between the plots with the most and the l

关键词： allometry ground water life history tree-age distribution tugai forest

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Clones or no clones：genetic structure of riparian Populus euphratica forests in Central Asia

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Journal of Arid Land 2018年第5期10卷 750-766页

作者： Katja KRAMP Thomas SCHMITT Petra LANG michael jeschke Philipp SCHAFERI Dustin KULANEK ZHANG Ximing YU Ruide Frank M THOMAS Senckenberg German Entomological Institute Eberswalder StraBe 90 Muncheberg 15374 Germany Department of Zoology Faculty Natural Sciences I Institute of Biology Martin Luther University Halle-Wittenberg Halle (SaMe) 06099 Germany Faculty of Regional and Environmental Sciences University of Trier Campus II BehringstraBe 21 Trier 54296 Germany Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Sino-German Joint Research Center for the Management of Ecosystems and Environmental Changes in Arid Lands (MEECAL) Urumqi 830011 China

Many riparian（Tugai） forests growing along rivers in arid and hyper-arid regions of Central Asia are dominated by the Euphrates poplar（Populus euphratica）. Besides generative reproduction, which is only possible upon flooding events and at a distance to the groundwater of less than 2 m, this phreatophytic tree species also reproduces vegetatively by forming clones that can cover land surface areas of several hectares. Along a gradient of groundwater distances, we investigated whether the fraction of clones in P. euphratica stands（1） increases with increasing distance to the water table;（2） is higher if supplied with water via river cut-offs; and（3） approaches 100% at a short distance to the groundwater, but at high salt concentrations in the upper soil layers, which would prevent germination and establishment of seedlings. AFLP（Amplified Fragment Length Polymorphism） analyses were conducted on leaf samples taken from mature P. euphratica trees growing at the fringes of the Taklimakan Desert in stands with different distances（2–12 m） to the groundwater at two plots at the middle and the lower reaches of the Tarim River and in a stand close to Ebinur Lake, Xinjiang, China. Genetic diversity was large among plots, but considerably smaller within plots. We found the highest genetic diversity（caused by regeneration from seeds） at plots that have a short distance to the groundwater or are supplied with additional water. There was no significant relationship between groundwater distance and clonal fraction. All investigated trees at the saline Ebinur Lake site belonged to one single clone. Our results demonstrate that the genetic pattern of this widespread species is not easily predictable even over small distances as it is a result of a complex interplay of stand history and dispersal of propagules（pollen, seeds, and vegetative diaspores） by wind and water. In conservation and restoration schemes, P. euphratica stands with a high genetic diversity and stands that grow at short distances to the water table and are regul

关键词： clonality floodplain forest ground water phreatophyte population genetics rejuvenation salinity

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Neuronal trafficking as a key to functional recovery in immune-mediated neuropathies

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Neural Regeneration Research 2024年第11期19卷 2331-2332页

作者： Felix Kohle michael Schroeter Department of Neurology University of Cologne and University Hospital CologneCologneGermany

Immune-mediated neuropathies are rare diseases of the peripheral nervous system(PNS),substantially affecting patients’functionality and quality of life.They are amenable to immunomodulatory treatments,which in many cases stabilize disease progression,but long-term deficits persist in many patients.Such long-term deficits are particularly observed in monophasic autoimmune neuropathies like Guillain-Barrésyndrome and also in chronic variants,e.g.,chronic inflammatory demyelinating neuropathy(Fadia et al.,2019).

关键词： diseases autoimmune

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Commentary on"Speed and surface steepness affect internal tibial loading during running"

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Journal of Sport and Health Science 2024年第1期13卷 125-126页

作者： michael Baggaley Arash Khassetarash Faculty of Kinesiology University of CalgaryCalgaryAB T2N 1N4Canada McCaig Institute for Bone and Joint Health University of CalgaryCalgaryAB T2N 4Z6Canada

It is a pleasure to write a commentary on the work of Dr.Hannah Rice and colleagues,l who have advanced our understanding of how the mechanical loading environment of the tibia changes as a function of running grade and speed.It is important that we understand how the tibia is loaded during conditions that an individual is likely to encounter when running as it is these internal loads which we believe are responsible for the development of bone-stress injuries.

关键词： loading injuries likely

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Transcranial photobiomodulation for the brain: a wide range of clinical applications

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Neural Regeneration Research 2024年第3期19卷 483-484页

作者： michael R.Hamblin Laser Research Centre Faculty of Health ScienceUniversity of Johannesburg-Doornfontein CampusDoornfonteinSouth Africa

Photobiomodulation therapy(PBMT)is a rapidly growing approach to the healing,stimulation,protection,and regeneration of many human organs and tissue types.PBMT started in the 1960s as low-level laser therapy for wound healing,but since then the introduction of light-emitting diodes(LEDs)has dramatically increased the number of applications and reports of positive results.PBMT generally uses red(620-700 nm)and/or near-infrared(780-1270 nm)wavelengths of light at an intensity that causes no tissue heating,and its activity is based on well-established biological and cellular mechanisms(de Freitas and Hamblin,2016).While laser therapists continue to use various types of laser in their office practice,LEDs are ideally suited for home use devices because they are completely safe and without any known significant adverse effects.Among the various body parts on which PBMT has been shown to exert beneficial effects,the brain stands out as perhaps the most promising overall.PBMT has been shown to reduce neuroinflammation,while increasing mitochondrial function,oxygen consumption,and blood flow within the brain(Hamblin,2016).Moreover,PBMT can stimulate the processes of synaptogenesis,neurogenesis,and neuroplasticity thus helping the brain to heal itself.

关键词： healing stimulation wound

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Benign stricture of bilioenteric anastomosis after Whipple withsynthetic polypropylene suture

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 103-105页

作者： A michael Devane Christine MG Schammel Department of Radiology Prisma Health UpstateGreenvilleUSA Department of Pathology Prisma Health UpstateGreenvilleUSA

To the Editor:Biliary stricture formation at the bilioenteric anastomosis is an infrequent complication(2%-3%)after pancreaticoduodenectomy;the average presentation is within 13-14 months(range from 1 month to 9 years)after surgery[1,2].While the etiology is unknown,development of biliary stricture has shown to be more likely if a bile leak occurs in the postoperative period[3,4]and with younger patients[5].

关键词： stricture anastomosis Whipple

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Fabrication of sub-20 nm MoS_(2) horizontal nanowire on silicon substrates by inclusion of precursors into polystyrene-bpolyethylene oxide nanopatterns: Detailed structural investigation

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Nano Research 2024年第3期17卷 2145-2153页

作者： Tandra Ghoshal michael A.Morris School of Chemistry AMBER and CRANNTrinity College DublinDublinIrelandD02 AK60

Herein,we demonstrate the fabrication of sub-20 nm MoS_(2) horizontal nanowire arrays on silicon substrates using a self-assembled block copolymer assisted in situ inclusion approach.Microphase separated long-range ordered polystyrene-b-polyethylene oxide(PS-b-PEO)block copolymer(BCP)line-space nanopatterns were achieved through thermo-solvent annealing.The patterns produced had long-range order and domain sizes>1μm.The BCP structures were lightly etched and modified by anhydrous ethanol to facilitate insertion of molybdenum precursor within the film maintaining the parent BCP arrangements.Horizontal ordered molybdenum oxide nanowire arrays were then fabricated by ultraviolet(UV)/ozone treatment at room temperature.The oxides were converted to sulphides by thermal evaporation at different temperatures in Ar/H_(2) environment.X-ray photoelectron spectroscopy revealed the composition and phases of the molybdenum oxide and sulphide nanowires.Elemental mapping was performed to investigate the interfaces between the oxide and sulphide nanowires with the substrate surface.The formation and stability of the sulphide nanowires were studied at different temperatures.The photoluminescence and Raman properties were studied at different formation temperatures to investigate defects and estimate the number of layers.

关键词： MoS_(2) block copolymer nanowires inclusion X-ray photoelectron spectroscopy(XPS) mapping photoluminescence

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amplitude modulation;high-frequency modulation;autoresonance;ion acoustic wave

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High Power Laser Science and Engineering 2024年第1期12卷 74-83页

作者： michael Valdman Amir Hen Gilad Marcus Applied Physics Institute Hebrew University of JerusalemJerusalemIsrael

The generation and control of large amplitude plasma gratings and other plasma structures is of paramount importance for the realization of plasma photonics. Autoresonant excitation of such structures by means of chirped amplitude-modulated lasers has been recently discussed and analyzed theoretically. Here we discuss the parameter space for the realization of such a scheme and describe the laser system that was built towards this goal. We also expand our earlier theoretical study to account for the more realistic case of a moderately focused laser beam, instead of the simplified plane wave approximation.

关键词： amplitude modulation high-frequency modulation autoresonance ion acoustic wave

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Mesenchymal stem cell-derived extracellular vesicles as a cell-free therapy for traumatic brain injury via neuroprotection and neurorestoration

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Neural Regeneration Research 2024年第1期19卷 49-54页

作者： Ye Xiong Asim Mahmood michael Chopp Department of Neurosurgery Henry Ford HospitalDetroitMIUSA Department of Neurology Henry Ford HospitalDetroitMIUSA Department of Physics Oakland UniversityRochesterMIUSA

Traumatic brain injury is a serious and complex neurological condition that affects millions of people worldwide.Despite significant advancements in the field of medicine,effective treatments for traumatic brain injury remain limited.Recently,extracellular vesicles released from mesenchymal stem/stromal cells have emerged as a promising novel therapy for traumatic brain injury.Extracellular vesicles are small membrane-bound vesicles that are naturally released by cells,including those in the brain,and can be engineered to contain therapeutic cargo,such as anti-inflammatory molecules,growth factors,and microRNAs.When administered intravenously,extra cellular vesicles can cross the blood-brain barrier and deliver their cargos to the site of injury,where they can be taken up by recipient cells and modulate the inflammatory response,promote neuroregeneration,and improve functional outcomes.In preclinical studies,extracellular vesicle-based therapies have shown promising results in promoting recove ry after traumatic brain injury,including reducing neuronal damage,improving cognitive function,and enhancing motor recovery.While further research is needed to establish the safety and efficacy of extra cellular vesicle-based therapies in humans,extra cellular vesicles represent a promising novel approach for the treatment of traumatic brain injury.In this review,we summarize mesenchymal ste m/stromal cell-de rived extracellular vesicles as a cell-free therapy for traumatic brain injury via neuroprotection and neurorestoration and brainderived extracellular vesicles as potential biofluid biomarkers in small and large animal models of traumatic brain injury.

关键词： biomarkers extracellular vesicles functional outcome mesenchymal stem/stromal cells neuroinflammation neuroplasticity neuroprotection traumatic brain injury

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Recent development and challenges in enhancing fire performance on wood and wood-based composites:A 10-year review from 2012 to 2021

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Journal of Bioresources and Bioproducts 2024年第1期9卷 27-42页

作者： Charles michael Albert Kang Chiang Liew Faculty of Tropical Forestry Universiti Malaysia SabahKota Kinabalu 88400Kota KinabaluSabah 88400Malaysia

Due to their durability,versatility,and aesthetic value,wood and wood-based composites are widely used as building materials.The fact that these materials are flammable,however,raises a major worry since they might cause fire hazards and significant loss of life and property.The article investigates the variables that affect fire performance as well as the various fire-retardant treatments and their mechanisms.The current developments and challenges in improving the fire performance of wood and wood-based composites treated with fire-retardant materials are summarized in this paper.Nanoparticles,organic chemicals,and densification are some recent developments in fire-retardant treatments that are also emphasized.Key points from the review are summarized,along with potential areas for further research and development.

关键词： Fire performance Fire-retardant materials Wood Wood-based composite Nanoparticles coating Surface charring Bio-based fire retardant Densification

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