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Acacia mangium Willd: benefits and threats associated with its increasing use around the world

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Forest Ecosystems 2019年第1期6卷 13-25页

作者： Lydie-Stella Koutika david m.Richardson CRDPI Centre de Recherche sur la Durabilité et la Productivité des Plantations Industrielles Centre for Invasion Biology Department of Botany & Zoology Stellenbosch University

Background: Acacia mangium, a fast-growing tree native to parts of Indonesia, Papua New Guinea and Australia,has been cultivated outside its native environment and introduced into humid tropical lowland regions of Asia,South America and Africa over the last few decades. It is a multipurpose tree used in agroforestry, forestry and for restoration of degraded lands. It is also highly invasive in many regions where it has been introduced outside its native range. This paper reviews evidence of its obvious benefits and its negative impacts on ***: A literature review on Australian acacias and especially on A. mangium was undertaken to highlight both benefits and threats associated with their increasing worldwide use outside their native ***: Through N_2 fixed from the atmosphere, A. mangium improves soil fertility, especially by increasing N status and soil C accretion when introduced to N-limited areas; it thus has the potential to restore nutrient cycling in degraded systems. No studies have, however, been done to assess the effectiveness of A. mangium in restoring biodiversity of degraded lands. most Australian acacias have traits that facilitate invasiveness, and 23 species have been recorded as invasive to date. A. mangium has been reported as invasive in Asia, Indonesia, Pacific Islands,Indian Ocean Islands, southern Africa and Brazil. Research on other invasive Australian acacias in several parts of the world has elucidated the types of impacts that are likely in different types of ecosystems and key options for mitigating ***: A. mangium has the potential to restore nutrient cycling in degraded systems, but is highly invasive wherever it is planted. many parts of the world have a large invasion debt for this species. Experience with other invasive acacias around the world suggests a suite of interventions that could be used to reduce invasions and mitigate impacts. Careful risk assessments should be undertaken prior to

关键词： Biodiversity Biological invasions C sequestration Soil N status Tree invasions

RNA m^(6)A reader YTHDF2 facilitates precursor miR-126 maturation to promote acute myeloid leukemia progression

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Genes & Diseases 2024年第1期11卷 382-396页

作者： Zheng Zhang Keren Zhou Li Han Andrew Small Jianhuang Xue Huilin Huang Hengyou Weng Rui Su Brandon Tan Chao Shen Wei Li Zhicong Zhao Ying Qing Xi Qin Kitty Wang Keith Leung mark Boldin Chun-Wei Chen david Ann Zhijian Qian Xiaolan Deng Jianjun Chen Zhenhua Chen Department of Systems Biology Beckman Research Institute of City of HopeMonroviaCA 91016USA Irell and manella Graduate School of Biological Sciences Beckman Research Institute of City of HopeDuarteCA 91010USA Gehr Family Center for Leukemia Research City of HopeDuarteCA 91010USA Sun Yat-sen University Cancer Center State Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangzhouGuangdong 510060China Guangzhou Laboratory GuangzhouGuangdong 510005China Bioland Laboratory GuangzhouGuangdong 51005China Department of Liver Surgery Renji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China Department of Diabetes Complications and metabolism Beckman Research Institute of City of HopeDuarteCA 91010USA Department of Biochemistry and molecular Biology University of FloridaGainesvilleFL 32603USA Tongji Hospital Affiliated to Tongji University Frontier Science Center for Stem Cell ResearchSchool of Life Sciences and TechnologyTongji UniversityShanghai 200092China School of Pharmacy China Medical UniversityShenyangLiaoning 110001China

As the most common internal modification of mRNA,Ne-methyladenosine(m^(6)A)and its regulators modulate gene expression and play critical roles in various biological and patholog-ical processes including *** was reported previously that m^(6)A methyltransferase(writer),methyltransferase-like 3(mETTL3)adds m^(6)A in primary microRNAs(pri-miRNAs)and fa-cilitates its processing into precursor miRNAs(pre-miRNAs).However,it is unknown whether m^(6)A modification also plays a role in the maturation process of pre-miRNAs and(if so)whether such a function contributes to ***,we found that YTHDF2 is aberrantly overexpressed in acute myeloid leukemia(AmL)patients,especially in relapsed patients,and plays an onco-genic role in ***,YTHDF2 promotes expression of miR-126-3p(also known as miR-126,as it is the main product of precursor miR-126(pre-miR-126)),a miRNA that was reported as an oncomiRNA in AmL,through facilitating the processing of pre-miR-126 into mature ***,YTHDF2 recognizes m^(6)A modification in pre-miR-126 and recruits AGO2,a regulator of pre-miRNA processing,to promote the maturation of ***2 posi-tively and negatively correlates with miR-126 and miR-126's downstream target genes,respec-tively,in AmL patients,and forced expression of miR-126 could largely rescue YTHDF2/Ythdf2 depletion-mediated suppression on AmL cell growth/proliferation and leukemogenesis,indi-cating that miR-126 is a functionally important target of YTHDF2 in ***,our studies not only reveal a previously unappreciated YTHDF2/miR-126 axis in AmL and highlight the ther-apeutic potential of targeting this axis for AmL treatment,but also suggest that m^(6)A plays a role in pre-miRNA processing that contributes to tumorigenesis.

关键词： AmL miR-126 N^(6)-methyladenosine Pre-miRNA maturation YTHDF2

Province-scale commonalities of some world-class gold deposits:Implications for mineral exploration

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Geoscience Frontiers 2015年第3期6卷 389-399页

作者： david I.Groves m.Santosh Centre for Exploration Targeting UWA State Key Laboratory of Geological Processes and mineral Resources China University of Geosciences Centre for Tectonics Resources and Exploration Dept.of Earth SciencesUniversity of Adelaide Division of Interdisciplinary Science Faculty of ScienceKochi University

Discovery rates for all metals, including gold, are declining, the cost per significant discovery is increasing sharply, and the economic situation of the industry is one of low base rate. The current hierarchical structure of the exploration and mining industry makes this situation difficult to redress. Economic geologists can do little to influence the required changes to the overall structure and philosophy of an industry driven by business rather than geological principles, However, it should be possible to follow the lead of the oil industry and improve the success rate of greenfield exploration, necessary for the next group of lower-exploration-spend significant mineral deposit discoveries. Here we promote the concept that mineral explorers need to carefully consider the scale at which their exploration targets are viewed. It is necessary to carefully assess the potential of drill targets in terms of terrane to province to district scale, rather than deposit scale, where most current economic geology research and conceptual thinking is concentrated. If orogenic, IRGD, Carlin-style and IOCG gold-rich systems are viewed at the deposit scale, they appear quite different in terms of conventionally adop- ted research parameters. However, recent models for these deposit styles show increasingly similar source-region parameters when viewed at the lithosphere scale, suggesting common tectonic settings. It is only by assessing individual targets in their tectonic context that they can be more reliably ranked in terms of potential to provide a significant drill discovery. Targets adjacent to craton margins, other lithosphere boundaries, and suture zones are clearly favoured for all of these gold deposit styles, and such exploration could lead to incidental discovery of major deposits of other metals sited along the same tectonic boundaries.

关键词： mineral exploration Gold deposits Tectonic settings mining industry Discovery rate

Contemporary and Historic Population Structure of Abies spectabilis at Treeline in Barun Valley,Eastern Nepal Himalaya

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Journal of mountain Science 2015年第3期12卷 558-570页

作者： Parveen Kumar CHHETRI david m.CAIRNS Department of Geography Texas A&M UniversityCollege Station

Treeline ecotone dynamics of Abies spectabilis （D. Don） mirb. in the Barun valley, makalu Barun National Park, eastern Nepal Himalaya were studied by establishing seven plots （20 m x variable length） from the foresfline to the tree species limit： three plots on the south- and north-facing slopes each （S1-S3, N1-N3）, and one plot on the east- facing slope （E） in the relatively undisturbed forests. A dendroecological method was used to study treeline advance rate and recruitment pattern. In all the plots, most trees established in the early 20th century, and establishment in the second half of the 20th century was confined to the foresfline area. Treeline position has not advanced substantially in the Barun valley, with 0nly 22 m average elevational shift in the last 13o years, and with average current shifting rate of 14 cm/yr. moreover, no significant relationship was found between tree age and elevation on the south-, north-, and east-facing slopes. The number of seedlings and saplings in near the treeline area was negligible compared to that near the foresfline area. Therefore, A. spectabilis treeline response to the temperature change was slow, despite the increasing temperature trend in the region. Beside the temperature change, factors such as high inter-annual variability in temperature, dense shrub cover, and local topography also play an important role in treeline advance and controlling recruitment pattern above the treeline.

关键词： Climate change Treeline ecotone Treeline advance Recruitment pattern

The giant Jiaodong gold province： The key to a unified model for orogenic gold deposits？

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Geoscience Frontiers 2016年第3期7卷 409-417页

作者： david I.Groves m.Santosh Centre for Exploration Targeting UWA Cmwley 6009 WA Australia Centre for Tectonics Resources and Exploration Department of Earth Sciences University of Adelaicle SA 5005 Australia State Key Laboratory of Geological Processes and mineral Resources China University of Geosciences Beijing 100083 China Division of Interdisciplinary Science Faculty of Science Kochi University Kochi 780-8520 Japan

Although the term orogenic gold deposit has been widely accepted for all gold-only lode-gold deposits,with the exception of Carlin-type deposits and rare intrusion-related gold systems,there has been continuing debate on their *** syngenetic models and hydrothermal models dominated by meteoric fluids are now clearly ***-hydrothermal models fail to explain the genesis of orogenic gold deposits because of the lack of consistent spatially- associated granitic intrusions and inconsistent temporal *** most plausible,and widely accepted,models involve metamorphic fluids,but the source of these fluids is hotly *** within deeper segments of the supracrustal successions hosting the deposits,the underlying continental crust,and subducted oceanic lithosphere and its overlying sediment wedge all have their *** orogenic gold deposits of the giant Jiaodong gold province of China,in the delaminated North China Craton,contain ca.120 ma gold deposits in Precambrian crust that was metamorphosed over 2000 million years prior to gold *** only realistic source of fluid and gold is a subducted oceanic slab with its overlying sulfide-rich sedimentary package,or the associated mantle *** could be viewed as an exception to a general metamorphic model where orogenic gold has been derived during greenschist- to amphibolite-facies metamorphism of supracrustal rocks：basaltic rocks in the Precambrian and sedimentary rocks in the ***,if a holistic view is taken,Jiaodong can be considered the key orogenic gold province for a unified model in which gold is derived from late-orogenic metamorphic devolatilization of stalled subduction slabs and oceanic sediments throughout Earth *** latter model satisfies all geological,geochronological,isotopic and geochemical constraints but the precise mechanisms of auriferous fluid release,like many other subduction-related processes,are model-driv

关键词： Jiaodong province Orogenic gold metamorphic fluids Subduction zones Tectonics

Dendroclimatic response of Abies spectabilis at treeline ecotone of Barun Valley, eastern Nepal Himalaya

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Journal of Forestry Research 2016年第5期27卷 1163-1170页

作者： Parveen Kumar Chhetri david m.Cairns Department of Geography Texas A&M UniversityCollege StationTX 77843-3147USA

A dendroclimatic study was conducted in the treeline ecotone of Barun Valley, eastern Nepal, to determine the tree-ring climate response and ring width trend of Abies spectabilis. A 160-year-old chronology, from 1850 to 2010, was developed from 38 tree-ring samples. No higher growth in recent decades was observed in tree-ring width in this area. The mean temperature of the current year in February and in the combined winter months of December, January, and February showed significant positive correlation with tree-ring width, although no significant correlation was found between tree-ring width and the precipitation pattern of the region. This tree-ring climate response result is different from that in other studies in Nepal, which could be attributed to location and elevation.

关键词： spectabilis Dendroclimatology Treeline ecotone Abies Climate response Tree-ring width

Dynamic Bubble Behaviour during microscale Subcooled Boiling

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Chinese Physics Letters 2005年第11期22卷 2881-2884页

作者：王昊彭晓峰 david m. Christopher Laboratory of Phase-Change and Interracial Transport Phenomena Department of Thermal Engineering Tsinghua University Beijing 100084

Bubble cycles, including initiation, growth and departure, are the physical basis of nucleate boiling. The present investigation, however, reveals unusual bubble motions during subcooled nucleate boiling on microwires 25 or 100μm in diameter. Two types of bubble motions, bubble sweeping and bubble return, are observed in the experiments. Bubble sweeping describes a bubble moving back and forth along the wire, which is motion parallel to the wire. Bubble return is the bubble moving back to the wire after it has detached or leaping above the wire. Theoretical analyses and numerical simulations are conducted to investigate the driving mechanisms for both bubble sweeping and return. marangoni flow from warm to cool regions along the bubble interface is found to produce the shear stresses needed to drive these unusual bubble movements.

关键词： subcooled boiling ELECTRIC WIRE driving mechanism bubbles Nucleate boiling Shear stress

The Effects of the Longitudinal Axis of Loading upon Bending, Shear and Torsion of a Thin-Walled Cantilever Channel Beam

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Temporal trends in 6-minute walking distance for older Japanese adults between 1998 and 2017

World Journal of mechanics（力学国际期刊） 2024年第5期 73页

作者： david W. A. Rees Abdelraouf m. Sami Alsheikh

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Journal of Sport and Health Science 2021年第4期10卷 462-469页

作者： Grant R.Tomkinson Tetsuhiro Kidokoro Trevor J.Dufner Shingo Noi John S.fitzgerald Holly m.Brown-Borg Department of Education Health and Behavior StudiesUniversity of North DakotaGrand ForksND 58202USA Alliance for Research in Exercise Nutrition and Activity(ARENA)School of Health SciencesUniversity of South AustraliaAdelaideSA 5000Australia Department of Health&Physical Education International Christian UniversityTokyo 181-8585Japan Nippon Sport Science University Tokyo 158-8508Japan Department of Biomedical Sciences University of North DakotaGrand ForksND 58202USA

Background:The 6-minute walking distance(6mWD)is an excellent measure of both functional endurance and *** primary aim of this study was to estimate temporal trends in 6mWD for older Japanese adults between 1998 and 2017;the secondary aim was to estimate concurrent trends in body size(i.e.,height and mass)and self-reported participation in exercise/***:Adults aged 65-79 years were *** nationally representative 6mWD data(n=103,505)for the entire period were obtained from the Japanese ministry of Education,Culture,Sports,Science and *** trends in means(and relative frequencies)were estimated at the gender-age level by best-fitting sample-weighted linear/polynomial regression models,with national trends estimated by a post-stratified population-weighting *** trends in distributional variability were estimated as the ratio of coefficients of ***:Between 1998 and 2017 there was a steady,moderate improvement in mean 6mWD(absolute=45 m(95%confidence interval(95%CI):43-47);percent=8.0%(95%CI:7.6%-8.4%);effect size=0.51(95%CI:0.48-0.54)).Gender-and age-related temporal differences in means were *** in 6mWD declined substantially(ratio of coefficients of variation=0.89,95%CI:0.87-0.92),with declines larger for women compared to men,and for 75-79-year-olds compared to ***,there were moderate and negligible increases in mean height and mass,respectively,and negligible increases in the percentage who participated in exercise/sport at least 3 days per week and at least 30 min per ***:There has been a steady,moderate improvement in mean 6mWD for older Japanese adults since 1998,which is suggestive of corresponding improvements in both functional endurance and *** substantial decline in variability indicates that the temporal improvement in mean 6mWD was not uniform across the *** in 6mWD are probably influenced by correspond

关键词： Aerobic exercise Aged Fitness testing Physical fitness Secular change