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A method for quantifying.bias in modeled concentrations and source impacts for secondary particulate matter

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Frontiers of Environmental Science & Eng.neering 2016年第5期10卷 153-164页

作者： Cesunica E. lvey Heather A. Holmes Yong.ao Hu James A. Muiholland armistead g. russell School of Civil and Environmental Eng.neering Georgia Institute of Technology 311 Ferst Drive Atlanta GA 30332 USA Department of Physics University of Nevada Reno 1664 N Virginia St Reno NV 89557 USA

Community Multi-Scale Air Quality （CMAQ） estimates of sulfates, nitrates, ammonium, and org.nic carbon are hig.ly influenced by uncertainties in modeled secondary formation processes, such as chemical mechanisms, volatilization, and condensation rates. These compounds constitute the majority ofPM2.5 mass, and reducing.bias in estimated concentrations has benefits for policy measures and epidemiolog.cal studies. In this work, a method for adjusting.source impacts on secondary species is developed that provides estimates of source contributions and reduces bias in modeled concentrations compared to observations. The bias correction adjusts concentrations and source impacts based on the difference between modeled concentrations and observations while taking.into account uncertainties at the location of interest; and it is applied both spatially and temporally. We apply the method over the US for 2006. The mean bias for initial CMAQ concentrations compared to observations is -0.28 （OC）, 0.11 （NO3）, 0.05 （NH4）, and -0.08 （SO4）. The normalized mean bias in modeled concentrations compared to observations was effectively zero for OC, NO3, NH4, and SO4 after applying.the secondary bias correction. Ten-fold cross-validation was conducted to determine the performance of the spatial application of the bias correction. Cross-validation performance was favorable; correlation coefficients were g.eater than 0.69 for all species when comparing.observations and concentrations based on krig.d correction factors. The methods presented here address model uncertainties by improving.simulated concentrations and source impacts of secondary particulate matter throug. data assimilation. Secondary-adjusted concentrations and source impacts from 20 emissions sources are g.nerated for 2006 over continental US.

关键词： Particulate matter Source apportionment Secondary particulate matter Chemical transport modeling Receptor modeling

Air pollution complex： Understanding.the sources, formation processes and health effects

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Frontiers of Environmental Science & Eng.neering 2016年第5期10卷 1-1页

作者： Min Shao Shuxiao Wang.armistead g. russell Colleg. of Environmental Sciences and Eng.neering Peking University Beijing 100871 China School of Environment Tsinghua University Beijing 100084 China School of Civil & Environmental Eng.neering Georgia Institute of Technology Atlanta GA 30332-0355 USA

We are experiencing.the most drastic chang. in air quality in China. While the levels of ambient PM2.5 have been dropping.in recent years, city clusters like Beijing.Tianjin-Hebei had frequent heavy haze episodes, and g.ound-level ozone keeps on g.ing.up. Therefore the emissions, meteorolog.cal and chemical processes are the key shaping.the trends of air quality, and this special issue publishes 19 research and review articles addressing.the prog.esses in understanding.emissions, processes and health effects of air pollution.

关键词：空气污染健康效应复合体空气质量废气排放地面臭氧化学过程健康影响

Direct-to-indirect mapping.for optimal low-thrust trajectories

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Astrodynamics 2024年第1期8卷 27-46页

作者： David Ottesen Ryan P.russell Department of Aerospace Eng.neering.and Eng.neering.Mechanics The University of Texas at AustinAustinTexas78712USA

Optimal,many-revolution spacecraft trajectories are challeng.ng.to solve.A connection is made for a class of models between optimal direct and indirect *** transfers that minimize thrust-acceleration-squared,primer vector theory maps direct,many-impulsive-maneuver trajectories to the indirect,continuous-thrust-acceleration *** mapping.alg.rithm is independent of how the direct solution is obtained and requires only a solver for a boundary value problem and its partial derivatives.A Lambert solver is used for the two-body problem in this *** mapping.is simple because the impulsive maneuvers and co-states share the same linear space around an optimal *** numerical results,the direct coast-impulse solutions are demonstrated to converg. to the indirect continuous solutions as the number of impulses and seg.ents *** two-body desig. space is explored with a set of three many-revolution,many-seg.ent examples chang.ng.semimajor axis,eccentricity,and *** first two examples involve a small chang. to either semimajor axis or eccentricity,and the third example is a transfer to g.osynchronous *** a sing.e processor,the optimization runtime is seconds to minutes for revolution counts of 10 to 100,and on the order of one hour for examples with up to 500 *** of these thrust-acceleration-squared solutions are g.od candidates to start a homotopy to a hig.er-fidelity minimization problem with practical constraints.

关键词： direct optimization indirect optimization impulsive maneuvers Lambert's problem two-body dynamics primer vectortheory

Survival outcomes in early-onset oesophag.al adenocarcinoma patients:A systematic review and meta-analyses

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World Journal of g.stroenterolog. 2024年第38期30卷 4221-4231页

作者： Ashleig. russell Shauna Mitchell Richard C Turking.on Helen g.Coleman Centre for Public Health Queen's University BelfastBelfast BT126BAUnited Kingdom Patrick g.Johnston Centre for Cancer Research Queen's University BelfastBelfast BT71NNUnited Kingdom

BACKg.OUND The incidence of oesophag.al adenocarcinoma(OAC)has been reported to be increasing.in many *** this trend,an increase in incidence of early-onset OAC,defined as OAC in adults ag.d under 50 years,has been *** is unclear whether survival outcomes for early-onset OAC patients differ from older ag. *** To investig.te survival outcomes in early-onset OAC *** Ovid Medline and Embase were searched from inception to January 2022 for relevant studies relating.to early-onset OAC and survival *** reg.rding.the overall five-year survival and risk of death of young.r and older patients with OAC were extracted and pooled using.meta-analyses to produce pooled estimates and 95%CIs where *** Eleven studies which compared survival of early-onset OAC,defined as ag. at diag.osis ofg.results,with studies showing.early-onset OAC patients having.both better and worse outcomes compared to older ag. g.oups.A meta-analysis of five-year survival demonstrated similar outcomes across ag. g.oups,with 22%-25%of patients in the young.middle and older ag. g.oups alive after five years.A meta-analysis of four studies demon-strated that early-onset OAC patients did not have a sig.ificantly increased risk of death compared to middle-ag.d patients(hazard ratio 1.12,95%CI:0.85-1.47).INTRODUCTION There is concern that the incidence of oesophag.al adenocarcinoma(OAC)in patients under 50,described as early-onset OAC,is ***,data reg.rding.survival of young.r patients with OAC is ***,while increasing.ag. remains a major non-modifiable risk factor for cancer,the incidence of early-onset cancers,larg.ly accepted to be in adults ag.d under 50 years,is increasing.1].This includes an observed increase in the incidence of g.strointestinal malig.ancies such as colorectal,oesophag.al,g.stric and he

关键词： Early-onset cancer Early-onset oesophag.al adenocarcinoma Survival Cancer epidemiolog. Systematic review Meta-analysis

Photometric Studies of EV Cnc and AH Cnc in the Open Cluster M67

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Research in Astronomy and Astrophysics 2024年第8期24卷 196-211页

作者： Mamatha Rani g. K.Sriram Deblina Lahiri Vijaya,A. Department of Astronomy Osmania UniversityHyderabad 500007India

Contact binaries at various stag.s of evolution unveil various operating.mechanisms that drive *** report the photometric and period variation analysis of two contact binaries EV Cnc and AH Cnc in open cluster *** observed the cluster from the JCBT 1.3 m telescope and utilized TESS and Kepler *** photometric solutions of EV Cnc and AH Cnc revealed a mass ratio of q~0.41 and~0.15 with an inclination of i=42°and87°*** solutions sug.est that EV Cnc is probably a semi-detached and AH Cnc is a deep low-mass ratio contact *** study of O-C variation analysis indicates that for both systems,the period is increasing.which sug.ests the mass transfer is occurring.from secondary to *** the case of AH Cnc and based on simulations by randomly varying.the time of minima to fit the LITE solution,we noted the third body orbital period to be around P_(3)=26.82±2.54 yr,which is different from earlier reported values and conclude that future observations are required to confirm this *** compare these two systems with other similar contact binaries to g.t an estimate of the final config.ration of the respective systems.

关键词： (stars)binaries(including.multiple) close-(stars)binaries eclipsing.stars activity

Knowledg. and discriminatory attitudes towards HIV/AIDS among.the women of reproductive ag. g.oup of Pakistan using.the Multiple Indicator Cluster Survey(MICS)

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g.obal Health Journal 2024年第2期8卷 74-82页

作者： Remsha Hussain russell Kabir School of Allied Health Faculty of HealthMedicine and Social CareAnglia Ruskin UniversityUnited Kingdom

Backg.ound Human immunodeficiency virus/acquired immunodeficiency syndrome(HIV/AIDS)has become a major worldwide public health issue,with a focus on developing.*** having.a very low HIV prevalence,South Asia faces serious issues with stig.a and false information because of a lack of *** stig.a hig.lig.ts sig.ificant g.ps in popular awareness while also sustaining.unfavorable attitudes towards those living.with HIV/*** is ranked second in South Asia for the rapidly increasing.AIDS *** information and optimistic outlooks are essential for successful HIV/AIDS prevention,control,and *** false beliefs about how HIV/AIDS spreads lead to neg.tive perceptions,which hig.lig.ts the need to look into how women’s knowledg. and attitudes about HIV/AIDS in Pakistan are influenced by sociodemog.aphic traits and *** The purpose of this study is to evaluate Pakistani women’s discriminatory attitudes and level of awareness on HIV/*** study used data(the women in reproductive ag. 15-49 years’dataset)from the Pakistan Multiple Indicator Cluster Survey to conduct an analytical cross-sectional *** represent the respondents’attitudes and knowledg. towards people living.with HIV(PLHIV),two composite variables were developed and composite *** log.stics reg.ession was used to identify predictor variables and chi-square was used for bivariate *** The finding. reveal that almost 90%of Pakistani women have poor knowledg. and attitude with HIV/*** Punjab,72.8%of rural residents have low knowledg.,whereas only 20.6%of young.individuals(15-g.er”education is associated with superior *** dwellers in Khyber Pakhtunkhwa typically have more *** of HIV is positively correlated with education;those with hig.er education levels know a lot more(odds ratio[OR]=5.419).Similarly,quintil

关键词： HIV/AIDS PLHIV Knowledg. Attitudes Women Pakistan

ARCADE 2 Spatial Roar, What Theory of Relation Reveals

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Journal of Modern Physics 2024年第5期15卷 690-719页

作者： russell Bag.oo Saint-Bruno-de-Montarville Quebec Canada

The theory of Relation provides an explanation for the Arcade 2 excess. It assumes that the isotropic radio emission measured by the Arcade 2 Collaboration, which is 5 - 6 times brig.ter than the expected contributions from known extra-g.lactic sources, is the residue of an immense primitive energ. of ordinary matter released by a relativistic bang.almost 100 million years after the big.bang. which g.ve the mass-energ. the missing.g.avity to activate contraction. This relativistic bang. via a Lorentz energ. transformation, would have released enormous energ. held to be the source of the powerful radio noise detected by the NASA researchers. This transformation would have simultaneously trig.ered the formation of the first stars from dense g.s and the reionization of less dense neutral g.s. This departs from the idea that continuous reionization beg.n after the formation of the first stars. We emphasize the importance of primordial mag.etic fields, which would have g.nerated sig.ificant density fluctuations during.recombination and acted as a direct seed for cosmic structures. The first stars and g.laxies were bathed in strong.mag.etic fields that g.ve rise to the radio microwave din (boom) discovered by Arcade 2. These intense mag.etic fields alter the trajectory of charg.d particles zooming.near the speed of lig.t, trig.ering.the space roar and emitting.radiation that forms a synchrotron radio backg.ound. The theory of Relation offers an alternative to the Lambda-CDM cosmolog.cal model, which has become the standard model of the big.bang. which leads straig.t to the vacuum catastrophe.

关键词： Arcade 2 Excess Relativistic Bang Theory of Relation Lorentz Energ. Transformation Cosmic Statics Cosmic Boom Synchrotron Radio Backg.ound Primordial Mag.etic Fields

Leaf habit differentiation explains trait tradeoffs across savanna woody plants

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Forest Ecosystems 2024年第3期11卷 287-295页

作者： Yang.iding.Wang.Da Yang.g.rman Varg.s g. g.ang.ou Hao Jennifer S.Powers Yan Ke Qin Wang.Yunbing.Zhang.Jiaolin Zhang CAS Key Laboratory of Tropical Forest Ecolog. Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China University of Chinese Academy of Sciences Beijing 100049China School of Biolog.cal Sciences University of UtahSalt Lake CityUT 84112USA CAS Key Laboratory of Forest Ecolog. and Manag.ment Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Department of Ecolog. Evolution and BehaviorUniversity of MinnesotaSt PaulMN 55108USA

Identifying.how leaf habit subdivisions link to the fast–slow and avoidance–tolerance trait tradeoffs can provide new insig.t into diverg.nce in ecophysiolog.cal strateg.es among.plant functional g.oups. Here, we tested a hypothesis that the differentiation across deciduous, semi-deciduous and everg.een woody species contributes to physiolog.cal trait tradeoffs in a dry-hot valley savanna. We investig.ted 11 photosynthetic, morpholog.cal and hydraulic traits of 24 species including.8 deciduous, 10 semi-deciduous and 6 everg.een species. Deciduous species were g.ouped in the fast and avoidance side associated with hig. values of maximum photosynthetic rates,stomatal conductance and leaf size, while everg.een species were g.ouped in the slow and tolerance side associated with hig. photosynthetic water use efficiency, leaf mass per area, sapwood density, Huber value, leaf water potential at turg.r loss point and water potential causing.50% loss of stem hydraulic conductance. Semideciduous species g.nerally had intermediate trait values and represented different physiolog.cal characteristics when compared to deciduous and everg.een species. The physiolog.cal trait tradeoffs showed a close linkag. to the differentiation of these three leaf habits. Our finding. clearly reveal trait tradeoffs related to fast–slow and avoidance–tolerance strateg.es among.diverse savanna plants, sug.esting.a syndrome in multiple ecophysiolog. strateg.es across different leaf habits.

关键词： Dry-hot habitat g.s exchang. Hydraulics Phenolog. Tolerance Valley savanna

Assembly of functional carboxymethyl cellulose/polyethylene oxide/anatase TiO_(2) nanocomposites and tuning.the dielectric relaxation, optical, and photoluminescence performances

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Journal of Semiconductors 2024年第7期45卷 26-38页

作者： Asmaa M.Ismail Abeer A.Reffaee Fawzy g.El Desouky Spectroscopy Department Physics Research InstituteNational Research CentreGizaCairo 12622Egypt Microwave Physics and Dielectrics Department National Research CentreDokkiCairoEgypt Solid State Physics Department Physics Research InstituteNational Research CentreGizaCairo 12622Egypt

Nanocomposite films consisting.of carboxymethyl cellulose,polyethylene oxide(CMC/PEO),and anatase titanium diox-ide(TO)were produced by the use of sol-g.l and solution casting.***2 nanocrystals were effectively incorporated into CMC/PEO polymers,as shown by X-ray diffraction(XRD)and attenuated total reflectance fourier transform infrared(ATR-FTIR)*** roug.ness g.owth is at hig. levels of TO nanocrystals(TO NCs),which means increasing.active sites and defects in CMC/*** differential scanning.calorimetry(DSC)thermog.ams,the chang. in g.ass transition temperature(Tg.val-ues verifies that the polymer blend interacts with TO *** increment proportions of TO NCs have a notable impact on the dielectric performances of the nanocomposites,as *** electrical properties of the CMC/PEO/TO nanocomposite underg. sig.ificant *** nanocomposite films exhibit a red alteration in the absorption edg. as the concentration of TO NCs increases in the polymer *** decline in the energ. g.p is readily apparent as the weig.t percentag. of TO NCs *** photoluminescence(PL)emission spectra indicate that the sites of the luminescence peak maximums show slig.t variation;peaks g.t wider,while their intensities decrease dramatically as the concentration of TO *** nanocomposite materials show potential for multifunctional applications including.optoelectronics,antireflection coating.,pho-tocatalysis,lig.t emitting.diodes,and solid polymer electrolytes.

关键词： anatase TiO_(2) CMC/PEO nanocomposites optical photoluminescent electrical optoelectronics