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喜马拉雅山不同森林群落主要树种叶片元素性状与生物量之间的关系

自动化学报（英文版） 2024年第9期 1967页

作者： Gopi ram

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中国科学：地球科学 2024年第5期54卷 1544-1555页

作者： Nita DYOLA 梁尔源 Josep PEÑUELAS JJulio CAMARERO Shalik ram SIGDEL Sugam ARYAL 林文涛刘向刘永稳徐兴良 Sergio ROSSI 中国科学院青藏高原研究所青藏高原地球系统与资源环境全国重点实验室北京100101 中国科学院大学北京100049 Laboratoire sur lesécosystèmes terrestres boréaux Département des Sciences FondamentalesUniversitédu QuébecàChicoutimi555Boulevard de l′UniversitéChicoutimi(QC)G7H2B1Canada CSIC Global Ecology Unit CREAF-CSIC-UABBellaterraE-08193 CataloniaSpain CREAF Cerdanyola del VallèsE-08193 CataloniaSpain Instituto Pirenaico de Ecología(IPE-CSIC) Avenida Montañana 1005Zaragoza 50059Spain Friedrich-Alexander-Universität Erlangen-Nürnberg Institut für GeographieErlangen 91058Germany 兰州大学生态学院草种创新与草地农业生态系统全国重点实验室兰州730000 中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室北京100101

植物需要多种基本元素调节并保持其特定比例以维持生长发育,叶片元素含量反映了植物的功能及其对环境的适应性.然而,在森林海拔梯度上,我们对于资源获取、光合作用和生长相关的叶片元素如何调节森林生物量仍知之甚少.本研究在喜马拉雅... 详细信息

植物需要多种基本元素调节并保持其特定比例以维持生长发育,叶片元素含量反映了植物的功能及其对环境的适应性.然而,在森林海拔梯度上,我们对于资源获取、光合作用和生长相关的叶片元素如何调节森林生物量仍知之甚少.本研究在喜马拉雅山干城章嘉峰地区沿热带森林(海拔80m)至高山树线(海拔4200m)设置海拔梯度样带,每间隔海拔100m设置一个样点,对116个树种的1859个个体测定了叶片中10种元素(C、N、P、K、Ca、Mg、Zn、Fe、Cu和Mn)的含量,通过计算叶片元素含量的群落加权平均值(反映优势物种的性状优势度,表征质量比效应)和功能离散度(反映物种在生态位空间内的聚集或者离散程度,表征互补效应),探究叶片元素含量及其离散程度沿海拔梯度分异特征,解析其对森林群落生物量的影响.研究结果表明,较强的叶片元素质量比效应和较弱的互补效应有利于森林群落生物量的积累.叶片元素性状多样性与海拔的共同作用对生物量的解释量(解释方差:52.2%)高于元素性状多样性的解释量(解释方差:0.05%~21%).海拔调节了树种性状多样性在生物量积累中的作用,互补效应在低海拔和高海拔地区对生物量的影响分别体现为积极和消极作用,这表明海拔和互补效应之间也存在交互作用.此外,海拔和质量比效应的交互作用对海拔梯度上生物量的影响也存在异质性.本研究表明,不同森林群落生物量的积累可能受到由海拔调控的性状多样性的影响.尽管较高的性状分异不利于生物量的积累,但能增强高海拔地区树种对胁迫环境的适应性.

关键词：生态系统功能海拔梯度功能多样性功能性状叶片元素生态位互补

Global prevalence and gender inequalities in at least 60 min of self-reported moderate-to-vigorous physical activity 1 or more days per week:An analysis with 707,616 adolescents

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Journal of Sport and Health Science 2024年第5期13卷 709-716页

作者： Raphael H.O.Araujo AndrúO.Werneck Clarice L.Martins Luciana L.Barboza Rafael M.Tassitano Nicolas Aguilar-Farias Gilmar M.Jesus Robinson ramírez-Véelez Riki Tesler Adewale L.Oyeyemi Ellen C.M.Silva Robert G.Weaver Mark S.Tremblay Javier Brazo-Sayavera Grégore I.Mielke Danilo R.P.Silva Graduation Program in Health Sciences Londrina State University(UEL)Londrina 86057-970Brazil Center for Epidemiological Research in Nutrition and Health Department of NutritionSchool of Public HealthUniversidade de Sao Paulo(USP)Sao Paulo 01246-904Brazil Department of Physical Education Federal University of ParaıbaParaıba 58051-900Brazil Research Centre of Physical Activity Health and LeisureFaculty of SportsLaboratory for Integrative and Translational Research in Population Health(ITR)University of PortoPorto 4500Portugal Postgraduate Program in Physical Education University of BrasıliaBrasılia 70910-900Brazil Department of Kinesiology and Community Health University of Illinois at Urbana-ChampaignChampaignIL 61801-3841USA Department of Physical Education Sports and RecreationUniversidad de La FronteraTemuco 4680000Chile Department of Health State University of Feira de SantanaFeira de Santana 44036-900Brazil Navarrabiomed Hospital Universitario de Navarra(HUN)Navarra Institute for Health Research(IdiSNA)Universidad Publica de Navarra(UPNA)Pamplona 31006Spain Facultad de Ciencias de la Educacion Unidad Central del Valle del Cauca(UCEVA)TuluaValle del Cauca 763022Colombia Health Management Department Faculty of Heath sciencesAriel UniversityAriel 40700Israel College of Health Solutions Arizona State UniversityPhoenixAZ 85004USA Arnold School of Public Health University of South CarolinaColumbiaSC 29208USA Healthy Active Living and Obesity Research Group Children’s Hospital of Eastern Ontario Research InstituteOttawaON K1H 8L1Canada Department of Pediatrics University of OttawaOttawaON K1H 8L1Canada Department of Health Sciences Carleton UniversityOttawaON K1S 5B6Canada Department of Sports and Computer Science Universidad Pablo de Olavide(UPO)Seville 41013Spain Centro Universitario Regional Noreste Universidad de la RepublicaRivera 40000Uruguay School of Public Health The University of QueenslandBrisbaneQLD 4006Australia Department of Physical Education

Background:Guidelines recommend that adolescents should accumulate an average of 60 min per day of moderate-to-vigorous physical activity(MVPA).However,using only this cut-off could hide important *** instance,from a population-level point of view,increasing physical activity for those with no or low physical activity could provide more health benefits than increasing physical activity for those with intermediate ***,including a more sensitive cut-point of≥1 days per week could be an additional strategy for identifying those with low access/opportunities for physical activity ***,the current study aims to estimate the prevalence of≥60 min of MVPA≥1 days per week among adolescents globally,and to describe any relevant gender ***:We used representative datasets from 146 countries/territories collected between 2003 and *** was *** were grouped into younger(≤14 years old)and older(>14 years old)*** Poisson regression models were used to identify the relative differences in≥60 min of MVPA≥1 days per week between boys and girls,and random-effects meta-analysis models were used to identify the pooled *** were stratified by country and ***:Approximately 80%of both younger and older adolescents reported≥60 min of MVPA≥1 days per *** prevalence was≥94%in Europe and Central Asia and North America,while the estimates for the other regions were14y)=1.09(95%CI:1.08-1.10)).Conclusion:Approximately 8 out of 10 adolescents reported accumulating≥60 min of MVPA≥1 days per week,with notable differences between *** differences were observed in several countries,especially among the oldest *** fo

关键词： Global School-based Student Health Survey Health Behaviour Among School-aged Children survey Inequality Surveillance Youth

An Overview of High-Performance Aircraft Structural Al Alloy-AA7085

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Acta Metallurgica Sinica(English Letters) 2015年第7期28卷 909-921页

作者： T.ram Prabhu CEMILAC Defence R&D Organization

AA7085 Al alloy is a new-generation,high-strength,quench-insensitive alloy that features in airframe applications such as massive bulkhead and wing spars structures in Airbus A380 and Joint Strike Fighter *** alloy has a great potential in replacing currently used high-strength AA7 xxx alloys in many international and national military aircraft programs [Hawk,Su-30,Mi G series,light combat aircraft（Tejas）,Hindustan turbo/jet trainer,light combat helicopter,advanced light helicopter,and fifth-generation fighter aircrafts].An effort has been made to highlight the processing,heat treatment,properties and applications of the AA7085 Al alloy from the existing literature on the AA7085 *** potential applications of this alloy are presented and compared with the currently used AA7075 Al alloy.A typical process cycle involved in the manufacturing of wrought AA7085 alloy products is described in ***,the precipitation mechanisms involved in the different temper conditions are critically reviewed with the supporting *** mechanical properties with a particular emphasis on tensile,fatigue,and fracture toughness properties are discussed in detail based on the analysis of experimental *** effects of temper conditions on the stress corrosion cracking and exfoliation corrosion have also been reviewed critically.

关键词： Al alloys Heat treatment Material processing Mechanical properties Corrosion

Syntrophic co-culture of Bacillus subtilis and Klebsiella pneumonia for degradation of kraft lignin discharged from rayon grade pulp industry

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Journal of Environmental Sciences 2015年第7期27卷 229-238页

作者： Sangeeta Yadav ram Chandra Department of Environmental Microbiology School for Environmental Sciences Babasaheb Bhimrao Ambedkar University (A Central University)

In order to search the degradability of kraft lignin, the potential bacterial strains Bacillus subtilis（GU193980） and Klebsiella pneumoniae（GU193981） were isolated, screened and applied in axenic and co-culture conditions. Results revealed that mixed culture showed better decolorization efficiency（80%） and reduction of pollution parameters（COD 73% and BOD62%） than axenic culture. This indicated syntrophic growth of these two bacteria rather than any antagonistic effect. The HPLC analysis of degraded samples of kraft lignin has shown the reduction in peak area compared to control, suggesting that decrease in color intensity might be largely attributed to the degradation of lignin by isolated ***, the GC-MS analysis showed that most of the compounds detected in control were diminished after bacterial treatment. Further, the seed germination test using Phaseolus aureus has supported the detoxification of bacterial decolorized kraft lignin for environmental safety. All these observations have revealed that the developed bacterial co-culture was capable for the effective degradation and decolorization of lignin containing rayon grade pulp mill wastewater for environmental safety.

关键词： Degradation GC-MS Kraft lignin Seed germination test Syntropic

Effect of heavy metals and phenol on bacterial decolourisation and COD reduction of sucrose-aspartic acid Maillard product

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Journal of Environmental Sciences 2013年第1期25卷 172-180页

作者： Sangeeta Yadav ram Chandra Department of Environmental Microbiology School for Environmental SciencesBabasaheb Bhimrao Ambedkar University (A Central University)

Melanodins are amino-carbonyl complex, predominantly present in sugarcane molasses based distillery wastewater as major source of colourant. The microbial decolourisafion of melanoidin is a challenge due to its binding property with other co-pollutants of distillery waste. Results revealed that the presence of Zn2＋（2.00-20.00 mg/L） in melanoidin solution （1200 mg/L） stimulated the bacterial growth and sucrose-aspartic acid Maillard product （SAA） decolourisation as compared to control, while Fe3＋ and Mn2＋ at the same concentration inhibited the process. However, the presence of phenol （100 mg/L） along with Zn2＋, Fe3＋ and Mn2＋ suppressed the bacterial growth, SAA decolourisation and MnP activity. The shrinkage and reduced number of bacterial cell count at higher concentration of heavy metals in presence of phenol was also observed under scanning electron microscope.

关键词： degradation manganese peroxidase melanoidin

Choice of precipitant and calcination temperature of precursor for synthesis of NiCo_2O_4 for control of CO–CH_4 emissions from CNG vehicles

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Journal of Environmental Sciences 2018年第3期30卷 62-71页

作者： Suverna Trivedi ram Prasad Department of Chemical Engineering &Technology Indian Institute of Technology (BHU)

Compressed natural gas（CNG）is most appropriate an alternative of conventional fuel for ***,emissions of carbon-monoxide and methane from such vehicles adversely affect human health and ***,to abate emissions from CNG vehicles,development of highly efficient and inexpensive catalysts is ***,the present work attempts to scan the effects of precipitants（Na2CO3,KOH and urea）for nickel cobaltite（Ni Co2O4）catalysts prepared by co-precipitation from nitrate solutions and calcined in a lean CO-air mixture at 400℃.The catalysts were used for oxidation of a mixture of CO and CH4（1：1）.The catalysts were characterized by X-ray diffractometer,Brunauer–Emmett–Teller surface-area,X-ray photoelectron spectroscopy;temperature programmedreductionandScanningelectronmicroscopycoupledwith Energy-Dispersive X-Ray *** Na2CO3was adjudged as the best precipitant for production of catalyst,which completely oxidized CO-CH4mixture at the lowest temperature（T（100）=350℃）.Whereas,for catalyst prepared using urea,T（100）=362℃.On the other hand the conversion of CO-CH4mixture over the catalyst synthesized by KOH limited to 97%even beyond 400℃.Further,the effect of higher calcination temperatures of 500 and600℃ was examined for the best *** total oxidation of the mixture was attained at higher temperatures of 375 and 410℃ over catalysts calcined at 500 and 600℃ ***,the best precipitant established was Na2CO3and the optimum calcination temperature of 400℃ was found to synthesize the Ni Co2O4catalyst for the best performance in CO-CH4oxidation.

关键词： CNG vehicular emissions CO-CH4 oxidation NiG0204 Precipitants Calcinations

Mysteries of R^ik=0： A novel paradigm in Einstein＇s theory of gravitation

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Frontiers of physics 2014年第1期9卷 98-112页

作者： ram Gopal Vishwakarma Unidad Academica de Matemdticas Universidad Autdnoma de Zacatecas C.P. 98068 Zacatecas ZAC Mexico

Despite a century-long effort, a proper energy-stress tensor of the gravitational field, could not have been discovered. Furthermore, it has been discovered recently that the standard formulation of the energy-stress tensor of matter, suffers from various inconsistencies and paradoxes, concluding that the tensor is not consistent with the geometric formulation of gravitation [Astrophys. Space Sci., 2009, 321： 151; Astrophys. Space Sei., 2012, 340： 373]. This perhaps hints that a consistent theory of gravitation should not have any bearing on the energy-stress tensor. It is shown here that the so-called ＂vacuum＂ field equations Rik = 0 do not represent an empty spacetime, and the energy, momenta and angular momenta of the gravitational and the matter fields are revealed through the geometry, without including any formulation thereof in the field equations. Though, this novel discovery appears baffling and orthogonal to the usual understanding, is consistent with the observations at all scales, without requiring the Moreover, the resulting theory circumvents the besides explaining some unexplained puzzles. hypothetical dark matter, dark energy or inflation long-standing problems of the standard cosmology

关键词： general relativity and gravitation - fundamental problems and general formalism cos-mological observations

Mysteries of the geometrization of gravitation

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Research in Astronomy and Astrophysics 2013年第12期13卷 1409-1422页

作者： ram Gopal Vishwakarma Unidad Acad'emica de Matem'aticas Universidad Aut'onoma de Zacatecas

As we now know, there are at least two major difficulties with general rel- ativity （GR）. The first one is related to its incompatibility with quantum mechanics, in the absence of a consistent, widely accepted theory that combines the two theo- ries. The second problem is related to the requirement of the dark sectors-inflaton, dark matter and dark energy by the energy-stress tensor, which are needed to explain a variety of astronomical and cosmological observations. Research has indicated that the dark sectors themselves do not have any non-gravitational or laboratory evidence. Moreover, the dark energy poses, in addition, a serious confrontation between funda- mental physics and cosmology. Guided by theoretical and observational evidences, we are led to an idea that the source of gravitation and its manifestation in GR should be modified. The result is in striking agreement with not only the theory, but also the ob- servations, without requiring the dark sectors of the standard approach. Additionally, it provides natural explanations to some unexplained puzzles.

关键词： general relativity and gravitation -- fundamental problems and generalformalism -- cosmology: observations

Rainfall Sensitivity to Microphysics and Planetary Boundary Layer Parameterizations in Convection-Permitting Simulations over Northwestern South America

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Journal of Meteorological Research 2024年第4期38卷 805-825页

作者： K.Santiago HERNANDEZ Sebastian GOMEZ-RIOS Juan J.HENAO Vanessa ROBLEDO Alvaro ramiREZ-CARDONA Angela M.RENDON Geolimna Escuela AmbientalFacultad de IngenieriaUniversidad de AntioquiaMedellin 050010Colombia Grupo de Ingenieria y Gestion Ambiental(GIGA) Escuela AmbientalFacultad de IngenieriaUniversidad de AntioquiaMedellin 050010Colombia Division of Atmospheric Sciences Desert Research InstituteRenoNV 89512USA

Convection-permitting modeling allows us to understand mechanisms that influence rainfall in specific ***,microphysics parameterization(MP) and planetary boundary layer(PBL) schemes remain an important source of uncertainty,affecting rainfall intensity,occurrence,duration,and ***,we study the sensitivity of rainfall to three MP [Weather Research and Forecasting(WRF) Single-Moment 6-class(WSM6),Thompson,and Morrison] and two PBL [the Yonsei University(YSU) and Mellor–Yamada Nakanishi Niino(MYNN)] schemes with a convection-permitting resolution(4 km) over northwestern South America(NWSA).Simulations were performed by using the WRF model and the results were evaluated against soundings,rain gauges,and satellite data,considering the spatio-temporal variability of rainfall over diverse regions prone to deep convection in *** and PBL schemes largely influenced simulated rainfall,with better results for the less computationally expensive WSM6 MP and YSU PBL *** rain gauges and satellite estimates,simulations with Morrison MP overestimated rainfall,especially westward of the Andes,whereas the MYNN PBL underestimated precipitation in the Amazon–Savannas *** found that the uncertainty in the rainfall representation is highly dependent on the region,with a higher influence of MP in the Colombian Pacific and PBL in the Amazon–Savannas *** analyzing rainfall-related processes,the selection of both MP and PBL parameterizations exerted a large influence on the simulated lower tropospheric moisture flux and moisture *** schemes significantly influenced the downward shortwave radiation,with MYNN simulating a greater amount of low clouds,which decreased the radiation ***,latent heat fluxes were greater for YSU,favoring moist convection and *** schemes had a marked impact on vertical ***,Morrison MP showed stronger convection and higher precipitation rates,which is assoc

关键词： sensitivity microphysics planetary boundary layer(PBL) Weather Research and Forecasting(WRF) processes