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Open Journal of Forestry 2015年第2期5卷 181-194页

作者： Juan Carlos Pena-Becerril Javier Alvarez-Sanchez Guadalupe Barajas-Guzmán Ana María Quiroz-Ayala Departamento de ecología y Recursos naturales Facultad de CienciasUniversidad Nacional Autónoma de MéxicoCiudad UniversitariaMexico CityMéxico

The effect of arbuscular mycorrhizal fungi on seedling growth across the rain forest-pasture edge has not received much attention. In a tropical rain forest in eastern Mexico, the seedlings of light demanding (Ficus insipida), nonsecondary light demanding (Lonchocarpus cruentus) and shade tolerant species (nectandra ambigens, Coccoloba hondurensis) were grown and transplanted to a forest edge with three inoculation treatments (AM fungus spores and colonized roots, spores, and no inoculum). For all species, stem height, stem diameter, total dry weight, leaf area and net assimilation rate were higher in the pasture. Stem height, stem diameter and root/shoot were higher for L. cruentus, and leaf area ratio, specific leaf area and net assimilation rate were higher for F. insipida;the lowest values of almost all variables were recorded for n. ambigens. L. cruentus and C. hondurensis with mycorrhizae had the highest values for root/shoot and net assimilation rate, respectively. The lowest values of root/shoot and net assimilation rate were observed for nonlight-demanding species in the forest. There were clear trade-offs for the pioneer species between survival and growth, and in underground biomass allocation and assimilation for nonsecondary light demanding, but there was not for the shade-tolerant species.

关键词： Arbuscular Mycorrhizal Fungi edge Forest Tropical Trees Trade-Offs Tropical Rain Forest

Properties of flyash based wood geopolymer composite

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Low-carbon Materials and Green Construction 2023年第1期1卷 391-404页

作者： B.S.Mamatha D.Sujatha D.n.Uday M.C.Kiran Scientist e. Institute of Wood Science and TechnologyGoIBangaloreIndia Scientist F. Institute of Wood Science and TechnologyGoIBangaloreIndia

Geopolymers are inorganic adhesive synthesized from industrial waste such as fly ash thus the development of wood geopolymer composite would be a low carbon footprint ***,being a non-formaldehyde adhesive can be used as an alternative binder for wood based composites where environmentally friendly and sustainability of product is *** this study flyash as precursor is been used in the development of wood geopolymer composite *** is activated with a combination of sodium hydroxide and sodium silicate solutions at a weight ratio of 1:2.5 for geopolymer *** study investigated the properties of wood geopolymer composite made with ratios of wood particle to flyash percentage(23/77),(37/62),(44/55),(50/50)and(57/43).Geopolymer formation was observed by X-ray Diffraction(XRD)and Fourier transform infrared spectroscopy(FTIR).Influence of wood particles in wood geopolymer composite were observed by Scanning electron *** study shows that the water absorption and thickness selling properties of all the formulations of wood geopolymer composites are comparable with the medium density particle board and cement-bonded particleboard according to the IS:3087-2005 standard and IS:12406:*** mechanical properties and good bond strength was obtained by the composite containing 23%wood particle ratio with 77%percent ***,still improvement in mechanical properties is needed to achieve the mechanical properties comparable to cement bonded particle board.

关键词： Geopolymer Composite Wood particle Inorganic adhesive Flyash

effects of delayed estrogen treatment and 20-HeTe synthesis inhibition on postischemic pial artery response to acetylcholine in rats

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Open Journal of Molecular and Integrative Physiology 2014年第1期4卷 1-10页

作者： Chikao Miyazaki emil n. Zeynalov Raymond C. Koehler Marguerite T. Littleton-Kearney Daniel K. Inouye Graduate School of nursing Uniformed Services University of the Health Sciences Bethesda USA Department of Anesthesiology/Critical Care Medicine School of Medicine Johns Hopkins University Baltimore USA

Relatively little is known about the effects of estrogen on postischemic cerebral vasomotor dynamics after ischemic injury. emerging hypotheses suggest that the timing after menopause at which hormone replacement is initiated might be important and might modulate the potential benefits of estrogen on brain rescue once a cerebral ischemic event occurs. Therefore, we sought to determine if protracted hypoestrogenicity modifies estrogen’s protective effects on postischemic pial artery dilatory dysfunction and if the arachidonic acid metabolite 20-hydroxyeicosatetraeonic (20-HeTe) contributes to the dysfunction. Pial artery dilation to acetylcholine was examined before and 1 hour after 15 minutes forebrain ischemia. The rat study groups included: sexually mature males (M), naive (n), OVX (OV), estrogen-treated OVX females (e1;estrogen started 1 week post ovariectomy) and delayed estrogen-treated (e10;started 10 weeks post ovariectomy) females. Postischemic responses were assessed before and after superfusion of the 20-HeTe synthesis inhibitor n-hydroxy-n’-(4-butyl-2-methylphenyl)-formamidine (HeT0016). Postischemic acetylcholine dilation was depressed in M, OV and e10 compared to n and e1 rats. Compared to e1, delayed estrogen replacement worsened acetylcholine-induced dilation. Postischemic microvascular estrogen receptor alpha (eRα) density was similar in the OV, e1 and e10 rats. Postischemic application of HeT0016 failed to improve acetylcholine dilation. Continuous infusion of HeT0016 during and after ischemia did not reverse postischemic pial vasodilatory dysfunction. Timing of estrogen replacement may be critical for vascular health after cerebral ischemic injury. Postischemic loss of acetylcholine reactivity does not appear to involve mechanisms related to 20-HeTe synthesis or microvascular eRα expression.

关键词： Hypoestrogenicity estrogen Replacement Cerebral Ischemia/Reperfusion Cerebral Microvessels estrogen Receptor Alpha 20-HeTe HeT0016

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俄国在远东

effect of Solid Wastes Composition and Confinement Time on Methane Production in a Dump

丛书名：俄国经略东方丛书

1975年

作者：（俄）科罗斯托维茨 n.R. 李金秋等译

本书是作者写的一本回忆录。记述了这个扩张主义分子在义和团运动时期，参加八国联军策划镇压义和团和建立殖民统治机构“天津都统衙门”的各种重要会议和从事侵略性的外交活动。

ISBN: (纸本)11017·360

关键词：历史、地理中国史半殖民地、半封建社会(1840~1949年)

来源：汇雅图书（南通市图书馆... 评论

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Journal of environmental Protection 2011年第10期2卷 1310-1316页

作者： Carlos González Otoniel Buenrostro Liliana Marquez Consuelo Hernández edgar Moreno Fabián Robles 不详

In developing countries, illegal dump structures or even some landfills do not include methane collecting systems, even if local environmental laws exist. In this condition, the greenhouse gas escapes to the atmosphere uncontrolled and practical solutions to tackle this problem are not obvious. To make a solution approachable, first-hand reliable data from dump emissions are required as starting point. The methane production is not homogeneous throughout the dump, therefore to estimate its global methane emissions, various representative gas monitoring sites distributed along the dump becomes necessary. This research work presents the measures of biogas emissions collected in the final disposal site located at Morelia (Mexico), along with an evaluation of the organic fraction and confinement time participation on biogas production. Biogas emission data were taken with a portable analyzer from 49 ventilation pipes for 52 weeks. For the composition and degradability analysis of solid wastes, the required samples have been collected from 16 sites. The results show a heterogeneous composition of solid wastes: 38 separate components are present, from those, 19 belong to organic categories and 28 of total components accounts for almost 99% of the waste. The mean biogas concentration detected was: 45.5% CH4, 32.4% CO2, 3.1% O2, and 18.9% balance gas (i.e., n2, CO or H2S). The AnOVA procedure clearly corroborated the influence of composition, biodegradability and time of confinement of solid wastes on the production of methane, despite the deficiencies in the final soil layer cover in these sites.

关键词： Mexico Biodegradability emissions Biogas Methane

MRI影像组学模型预测放化疗后直肠癌的病理完全缓解

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国际医学放射学杂志 2022年第4期 478-478页

作者： J.Shin n.Seo S.e.Baek n.H.Son J.S.Lim n.K.Kim 陈佳乐

摘要为了保存器官，越来越需要术前评估局部晚期直肠癌（LARC）新辅助放化疗（n CRT）后的病理完全缓解（p CR），但MRI影像组学模型仍然缺乏大规模验证。目的评

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Plant Growth-Promoting Traits in Rhizobacteria of Heavy Metal-Resistant Plants and Their effects on Brassica nigra Seed Germination

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Pedosphere 2017年第3期27卷 511-526页

作者： Brenda ROMn-POnCe Diana Miryel ReZA-VZQUeZ Sonia GUTIRReZ-PAReDeS María de Jesús De HARO-CRUZ Jessica MALDOnADO-HeRnnDeZ Yanely BAHenA-OSORIO Paulina eSTRADA-De LOS SAnTOS en Tao WAnG María Soledad VSQUeZ-MURRIeTA Instituto Politécnico nacional Escuela Nacional de Ciencias Biológicas Prolongación Carpio y Plan de Ayala s/n Col.Santo Tomás Del.Miguel Hidalgo Ciudad de México

Phytoremediation is an emerging technology that uses plants and their associated microbes to clean up pollutants from the soil, water, and air. In order to select the plant growth-promoting rhizobacteria （PGPR） for phytoremediation of heavy metal contamination, 60 bacterial strains were isolated from the rhizosphere of two endemic plants, Prosopis laevigata and Spharealcea angustifolia, in a heavy metal-contaminated zone in Mexico. These rhizobacterial strains were characterized for the growth at different pH and salinity, extracellular enzyme production, solubilization of phosphate, heavy metal resistance, and plant growth-promoting （PGP） traits, including production of siderophores and indol-3-acetic acid （IAA）. Overall, the obtained rhizobacteria presented multiple PGP traits. These rhizoba^teria were also resistant to high levels of heavy metals （including As as a metalloid）（up to 480 mmol L-1 As（V）, 24 mmol L-1 Pb（II）, 21 mmol L-1 Cu（II）, and 4.5 mmol L-1 Zn（II））. Seven rhizobacterial strains with the best PGP traits were identified as members of Alcaligenes, Bacillus, Curtobacterium, and Microbacterium, and were selected for further bioassay. The inoculation of Brassica nigra seeds with Microbacteriurn sp. Ce3R2, Microbacterium sp. ne1R5, Curtobacterium sp. nM1R1, and Microbacterium sp. nM3e9 facilitated the root development; they significantly improved the B. nigra seed germination and root growth in the presence of heavy metals such as 2.2 mmol L-1 Zn（II）. The rhizobacterial strains isolated in the present study had the potential to be used as efficient bioinoculants in phytorremediation of soils contaminated with multiple heavy metals.

关键词： bioinoculants endemic plants mine railings pH phytoremediation salinity

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A field guide for aging passerine nestlings using growth data and predictive modeling

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Avian Research 2021年第2期12卷 141-149页

作者： Audrey A.Sanchez Andrew W.Bartlow Allison M.Chan Jeanne M.Fair Aaron A.Skinner Kelly Hutchins Maria A.Musgrave emily M.Phillips Brent e.Thompson Charles D.Hathcock environmental Stewardship Los Alamos National LaboratoryLos AlamosNMUSA Biosecurity and Public Health Los Alamos National LaboratoryLos AlamosNMUSA Water Program N3BLos AlamosNMUSA

Background:Accurate nestling age is valuable for studies on nesting strategies,productivity,and impacts on repro-ductive *** aging guides consist of descriptions and photographs that are time consuming to read and subjective to *** Western Bluebird(Sialia mexicana)is a secondary cavity-nesting passerine that nests in coniferous and open deciduous *** box programs for cavity-nesting species have provided suitable nesting locations and opportunities for data collection on nestling growth and ***:We developed models for predicting the age of Western Bluebird nestlings from morphometric meas-urements using model training and *** were developed for mass,tarsus,and two different culmen ***:Our models were accurate to within less than a day,and each model worked best for a specific age *** mass and tarsus models can be used to estimate the ages of Western Bluebird nestlings 0-10 days old and were accurate to within 0.5 days for mass and 0.7 days for *** culmen models can be used to estimate ages of nest-lings 0-15 days old and were also accurate to within less than a *** daily mean,minimum,and maximum values of each morphometric measurement are provided and can be used in the field for accurate nestling age estimations in real ***:The model training and validation procedures used here demonstrate that this method can create aging models that are highly *** methods can be applied to any passerine species provided sufficient nest-ling morphometric data are available.

关键词： Cavity-nesting nest boxes nestling development Predictive models Western Bluebird

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X-ray Diffraction and electrical Conductivity Studies on Ag-Cu-Se System

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Journal of Materials Science & Technology 1995年第1期11卷 53-55页

作者： S.n.Motafa and S.R.Selim(Chemistry Department, Al-Azhar University, nasr City. Cairo. egypt)F.M.Ismail(Inorganic Chemistry Department, national Research Center. Dokki. Cairo. egypt) nATL ReS CTR DEPT INORGAN CHEMCAIROEGYPT AL-AZHAR UnIV DEPT CHEMNASREGYPT

A number of X-ray patterns and electrical conductivities of five different samples of Ag-Cu-Se system have been measured. These samples of Ag-Cu-Se system: (Ag1.188, Cu0.812)Se, (Ag,Cu)Se; (Ag0.9, Cu1.1 )Se, (Ag0.8, Cu1.2)Se and (Ag0.6, Cu1.4)Se were prepared under controlled conditions. Analysis of the experimental data shows that Frenkel defects are predominated in (Ag1.188, Cu0.812)Se and Schottky defects prevailing in the other samples. The activation energy values △e calculated from the linear behaviour of electrical conductivity a with temperature (0-90℃) reveal that the impurity content increases in the direction of (Ag,Cu)Se→(Ag0.8,Cu1.2 )Se

关键词： Ag X-ray Diffraction and electrical Conductivity Studies on Ag-Cu-Se System Cu

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Atomic and electronic basis for the serrations of refractory high-entropy alloys

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npj Computational Materials 2017年第1期3卷 253-262页

作者： William Yi Wang Shun Li Shang Yi Wang Fengbo Han Kristopher A.Darling Yidong Wu Xie Xie Oleg n.Senkov Jinshan Li Xi Dong Hui Karin A.Dahmen Peter K.Liaw Laszlo J.Kecskes Zi-Kui Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072 Shaanxi ProvinceChina Department of Materials Science and engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA U.S.Army Research Laboratory Weapons and Materials Research DirectorateRDRL-WMM-BAberdeen Proving GroundMD 21005USA State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Department of Materials Science and engineering The University of TennesseeKnoxvilleTN 37996USA Air Force Research Laboratory Materials and Manufacturing DirectorateWright-Patterson Air Force BaseOH 45433USA Department of Physics University of Illinois at Urbana ChampaignUrbanaIL 61801USA

Refractory high-entropy alloys present attractive mechanical properties,i.e.,high yield strength and fracture toughness,making them potential candidates for structural *** of atomic and electronic interactions are important to reveal the origins for the formation of high-entropy alloys and their structure−dominated mechanical properties,thus enabling the development of a predictive approach for rapidly designing advanced ***,we report the atomic and electronic basis for the valence−electron-concentration-categorized principles and the observed serration behavior in high-entropy alloys and highentropy metallic glass,including MonbTaW,MonbVW,MoTaVW,HfnbTiZr,and Vitreloy-1 MG(Zr_(41)Ti_(14)Cu_(12.5)ni_(10)Be_(22.5)).We find that the yield strengths of high-entropy alloys and high-entropy metallic glass are a power-law function of the electron-work function,which is dominated by local atomic ***,a reliance on the bonding-charge density provides a groundbreaking insight into the nature of loosely bonded spots in *** presence of strongly bonded clusters and weakly bonded glue atoms imply a serrated deformation of high-entropy alloys,resulting in intermittent avalanches of defects movement.

关键词： alloys toughness entropy