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Adaptive Random Effects/coefficients Modeling

Open j.urnal of Statistics 2024年第2期14卷 179-206页

作者： George j. Knafl School of Nursing University of North Carolina at Chapel Hill Chapel Hill USA

Adaptive fractional polynomial modeling of general correlated outcomes is formulated to address nonlinearity in means, variances/dispersions, and correlations. Means and variances/dispersions are modeled using generalized linear models in fixed effects/coefficients. correlations are modeled using random effects/coefficients. Nonlinearity is addressed using power transforms of primary (untransformed) predictors. Parameter estimation is based on extended linear mixed modeling generalizing both generalized estimating equations and linear mixed modeling. Models are evaluated using likelihood cross-validation (LcV) scores and are generated adaptively using a heuristic search controlled by LcV scores. cases covered include linear, Poisson, logistic, exponential, and discrete regression of correlated continuous, count/rate, dichotomous, positive continuous, and discrete numeric outcomes treated as normally, Poisson, Bernoulli, exponentially, and discrete numerically distributed, respectively. Example analyses are also generated for these five cases to compare adaptive random effects/coefficients modeling of correlated outcomes to previously developed adaptive modeling based on directly specified covariance structures. Adaptive random effects/coefficients modeling substantially outperforms direct covariance modeling in the linear, exponential, and discrete regression example analyses. It generates equivalent results in the logistic regression example analyses and it is substantially outperformed in the Poisson regression case. Random effects/coefficients modeling of correlated outcomes can provide substantial improvements in model selection compared to directly specified covariance modeling. However, directly specified covariance modeling can generate competitive or substantially better results in some cases while usually requiring less computation time.

关键词： Adaptive Regression correlated Outcomes Extended Linear Mixed Modeling Fractional Polynomials Likelihood cross-Validation Random Effects/coefficients

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j.vian Planet Influence on the Forcing of Sunspot cycles

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World j.urnal of condensed Matter Physics 2024年第1期14卷 1-9页

作者： Fred j. cadieu Physics Department Queens College of CUNY New York USA

The history of our solar system has been greatly influenced by the fact that there is a large gas giant planet, j.piter that has a nearly circular orbit. This has allowed relics of the early solar system formation to still be observable today. Since j.piter orbits the Sun with a period of approximately 12 years, it has always been thought that this could be connected to the nearly 11-year periodic peak in the number of sunspots observed. In this paper, the Sun and planets are considered to be moving about a center of mass point as the different planets orbit the Sun. This is the action of gravity that holds the solar system together. The center of mass for the j.piter-Sun system actually lies outside the Sun. The four gas giant planets dominate such effects and the four gas giant j.vian planets can be proj.cted together to determine an effective distance from the Sun’s center. Taken together these effects do seem to function as a sunspot forcing factor with a periodicity very close to 11 years. These predictions are made without consideration of any details of what is happening in the interior of the Sun. From these estimates, sunspot cycle 25 will be expected to peak in about September-October of 2025. Sunspot cycle 26 should peak in the year March of 2037.

关键词： Sun cycles Solar System Formation j.piter

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cO oxidation under lean and stoichiometric conditions over ceriazirconia with very low metal contents(cu,co,Ag and Pt)

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j.urnal of Rare Earths 2024年第9期42卷 1669-1681页

作者： j.c.Martínez-Munuera M.P.Yeste A.García-García McMA Group Department of Inorganic Chemistry and Institute of MaterialsUniversity of Alicante Solid chemistry and catalysis Group Department of Materials ScienceMetallurgic Engineering and Inorganic ChemistryInstitute of Electronic Microscopy and Materials ResearchUniversity of Cádiz

In this work,several ceria-zirconia based catalysts with very lo w（and equimolar） metal contents were prepared,characterised and tested for the cO oxidatio n reaction（under lean and stoichiometric conditions）,trying to emulate those conditions found in a diesel oxidation catalyst（DOc） system from a diesel engine and those encountered under gasoline exhaust（λ=1）.The metals chosen are cu,co,Ag and Pt（as a reliable benchmark）.The results reveal enormous differences among reducibility and catalytic activity despite quite similar structural and textural properties of the catalysts,showing differences among dispersion（Ag-catalyst seems to present a low level of dispersion）.This catalyst seems to be characterised,as well,by a strong electronic interaction between ce and Ag centres which is suggested to yield an improved reducibility under H2-TPR ***,the order in catalytic activity（cu>Ag>co≈Pt>>support） seems not to follow the order found in reducibility and the cu-catalyst seems to be the most active independently on the reaction conditions,yielding nearly overlapped cO oxidation catalytic *** restingly,a stro ng correlation between the catalytic activity under the two conditions tested and the OSc values of the ce0.8Zr0.2O2-supported metal catalysts is ***,OSc parameter measured at 150℃ can be used as a relevant descriptor to evaluate the cO oxidation activity at low and medium conversions for the investigated catalysts,much better than the H2-TPR measurements.

关键词： cO oxidation Low metal content ceria-zirconia copper species OSc parameter Rare earths

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A multi-shot target wheel assembly for high-repetition-rate, laser-driven proton acceleration

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High Power Laser Science and Engineering 2024年第2期12卷 87-94页

作者： j.Penas A.Bembibre D.cortina-Gil L.Martin A.Reij. c.Ruiz M.Seimetz A.Alej. j.Benlliure Instituto Galego de Fisica de Altas Enerxias Universidade de Santiago de CompostelaSantiago de CompostelaSpain Laboratorio Laser de Aceleracion y Aplicaciones RIAIDTUniversidade de Santiago de CompostelaSantiago de CompostelaSpain Instituto Universitario de Física Fundamental y Matematicas y Dpto.de Didactica de la Matematica y de las ciencias Experimentales Universidad de SalamancaSalamancaSpain Instituto de Instrumentación para Imagen Molecular(I3M) CSIC-Universitat Politecnica de ValenciaValenciaSpain

A multi-shot target assembly and automatic alignment procedure for laser–plasma proton acceleration at high repetition rate are *** assembly is based on a multi-target rotating wheel capable of hosting more than 5000 targets,mounted on a 3D motorized stage to allow rapid replenishment and alignment of the target material between laser *** automatic alignment procedure consists of a detailed mapping of the impact positions at the target surface prior to the irradiation that ensures stable operation of the target,which alongside the purpose-built design of the target wheel,enables operation at rates up to 10 *** and continuous laser-driven proton acceleration at 10 Hz is demonstrated,with observed cut-off energy stability about 15%.

关键词： high repetition rate laser-plasma acceleration multi-shot operation proton source target assembly

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comparative analysis of microstructure,mechanical,and corrosion properties of biodegradable Mg-3Y alloy prepared by selective laser melting and spark plasma sintering

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j.urnal of Magnesium and Alloys 2024年第4期12卷 1496-1510页

作者： P.Minárik M.Zemková S.Šašek j.Dittrich M.Knapek F.Lukáˇc D.Koutný j.j.roš R.Král Faculty of Mathematics and Physics Charles UniversityKe Karlovu 5Praha 12116Czech Republic Research centre University ofŽilinaUniverzitná8215/1Žilina 01026Slovakia Institute of Plasma Physics of the czech Academy of Sciences Za Slovankou 1782/318200 Praha 8Czech Republic Institute of Machine and Industrial Design Brno University of TechnologyTechnická2896/2Brno 61669Czech Republic

This work explored possibilities of biodegradable magnesium alloy Mg-3Y preparation by two modern powder metallurgy techniques–spark plasma sintering(SPS)and selective laser melting(SLM).The powder material was consolidated by both methods utilising optimised parameters,which led to very low porosity(∼0.3%)in the SLM material and unmeasurably low porosity in the SPS *** main aim of the study was the thorough microstructure characterisation and interrelation between the microstructure and the functional properties,such as mechanical strength,deformability,and corrosion *** materials showed comparable strength of∼110 MPa in tension and compression and relatively good deformability of∼9%and∼21%for the SLM and SPS materials,*** corrosion resistance of the SPS material in 0.1 M Nacl solution was superior to the SLM one and comparable to the conventional extruded *** digital image correlation during loading and the cross-section analysis of the corrosion layers revealed that the residual porosity and large strained grains have the dominant negative effect on the functional properties of the SLM *** the other hand,one of the primary outcomes of this study is that the SPS consolidation method is very effective in the preparation of the W3 biodegradable alloy,resulting in material with convenient mechanical and degradation properties that might find practical applications.

关键词： Magnesium Yttrium Powder metallurgy Microstructure Mechanical strength corrosion resistance

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Modeling of Total Dissolved Solids (TDS) and Sodium Absorption Ratio (SAR) in the Edwards-Trinity Plateau and Ogallala Aquifers in the Midland-Odessa Region Using Random Forest Regression and eXtreme Gradient Boosting

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j.urnal of Geoscience and Environment Protection 2024年第5期12卷 218-241页

作者： Azuka I. Udeh Osayamen j. Imarhiagbe Erepamo j. Omietimi Department of Geoscience University of Texas Permian Basin Odessa Texas USA Department of Geology University of Pretoria Pretoria South Africa

Efficient water quality monitoring and ensuring the safety of drinking water by government agencies in areas where the resource is constantly depleted due to anthropogenic or natural factors cannot be overemphasized. The above statement holds for West Texas, Midland, and Odessa Precisely. Two machine learning regression algorithms (Random Forest and XGBoost) were employed to develop models for the prediction of total dissolved solids (TDS) and sodium absorption ratio (SAR) for efficient water quality monitoring of two vital aquifers: Edward-Trinity (plateau), and Ogallala aquifers. These two aquifers have contributed immensely to providing water for different uses ranging from domestic, agricultural, industrial, etc. The data was obtained from the Texas Water Development Board (TWDB). The XGBoost and Random Forest models used in this study gave an accurate prediction of observed data (TDS and SAR) for both the Edward-Trinity (plateau) and Ogallala aquifers with the R2 values consistently greater than 0.83. The Random Forest model gave a better prediction of TDS and SAR concentration with an average R, MAE, RMSE and MSE of 0.977, 0.015, 0.029 and 0.00, respectively. For the XGBoost, an average R, MAE, RMSE, and MSE of 0.953, 0.016, 0.037 and 0.00, respectively, were achieved. The overall performance of the models produced was impressive. From this study, we can clearly understand that Random Forest and XGBoost are appropriate for water quality prediction and monitoring in an area of high hydrocarbon activities like Midland and Odessa and West Texas at large.

关键词： Water Quality Prediction Predictive Modeling Aquifers Machine Learning Regression eXtreme Gradient Boosting

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Polio eradication surveillance in Sri Lanka,2019-2023

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Asian Pacific j.urnal of Tropical Medicine 2024年第6期17卷 268-272页

作者： M.A.Y.Fernando N.S.Madarasinghe c.Rangana N.Weerasinghe D.c.U.D.Weligamage j.I.Abeynayake Department of Medical Microbiology and Immunology Faculty of MedicineUniversity of ColomboSri Lanka Department of Virology Medical Research InstituteColombo 08Sri Lanka Medical Research Institute Colombo 08Sri Lanka

Obj.ctive:To evaluate the polio laboratory surveillance carried out from j.nuary,2019 to May,2023 by the Polio Regional Reference Laboratory,Sri ***:This retrospective study analyzed all stool samples received under the acute flaccid paralysis(AFP)and immunodeficient vaccine-derived poliovirus(VDPV)surveillance at Polio Regional Reference Laboratory,Sri Lanka from j.nuary,2019 to May,*** results of the testing methodologies were extracted from the laboratory data system,i.e.,poliovirus virus isolation,intra-typic differentiation/VDPV real time reverse transcriptase polymerase chain reaction(ITD/VDPV rRTPcR)and sequencing,along with the data on timing of reporting results,stool adequacy and *** was analyzed using descriptive ***:A total of 2141 stool samples from 1644 cases were received for AFP surveillance from Sri Lanka(93.61%),Maldives(1.52%),and immunodeficient VDPV(4.86%)*** polioviruses(19/1644,1.15%)and non-polio enteroviruses(73/1644,4.44%)were isolated,while Sabin-like 3 virus was detected in maj.rity(12/19,63.15%)among the poliovirus *** polioviruses or circulating VDPVs were not detected among the *** all years of the study,the non-polio AFP detection rate was>1/100000 in children aged less than 15 years,whereas stool adequacy rate was>80%.All results were reported within 14 days of receipt,ensuring timely reporting as per global ***:The Polio Regional Reference Laboratory,Sri Lanka plays a vital role in maintaining the polio-free status in the country through its robust laboratory surveillance,while adhering to the surveillance ***-detection of wild polioviruses and circulating VDPV during the study period reinforces the polio-free status in the country.

关键词： Poliovirus Polio laboratory surveillance Regional reference laboratory Polio eradication

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Evaluation of a Wireless Solar Powered Personal Weather Station

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Agricultural Sciences 2024年第1期15卷 36-53页

作者： Robert j. Lascano Timothy S. Goebel Dennis c. Gitz III j.hn E. Stout cropping Systems Research Laboratory Wind Erosion and Water Conservation Research Unit USDA-ARS Lubbock TX USA

We are evaluating dryland cotton production in Martin county, Texas, measuring cotton lint yield per unit of rainfall. Our goal is to collect rainfall data per 250 - 400 ha. Upon selection of a rainfall gauge, we realized that the cost of using, for example, a tipping bucket-type rain gauge would be too expensive and thus searched for an alternative method. We selected an all-in-one commercially available weather station;hereafter, referred to as a Personal Weather Station (PWS) that is both wireless and solar powered. Our obj.ctive was to evaluate average measurements of rainfall obtained with the PWS and to compare these to measurements obtained with an automatic weather station (AWS). For this purpose, we installed four PWS deployed within 20 m of the Plant Stress and Water conservation Meteorological Tower that was used as our AWS, located at USDA-ARS cropping Systems Research Laboratory, Lubbock, TX. In addition, we measured and compared hourly average values of short-wave irradiance (Rg), air temperature (Tair) and relative humidity (RH), and wind speed (WS), and calculated values of dewpoint temperature (Tdew). This comparison was done over a 242-day period (1 October 2022-31 May 2023) and results indicated that there was no statistical difference in measurements of rainfall between the PWS and AWS. Hourly average values of Rg measured with the PWS and AWS agreed on clear days, but PWS measurements were higher on cloudy days. There was no statistical difference between PWS and AWS hourly average measurements of Tair, RH, and calculated Tdew. Hourly average measurements of Rg and WS were more variable. We concluded that the PWS we selected will provide adequate values of rainfall and other weather variables to meet our goal of evaluating dryland cotton lint yield per unit rainfall.

关键词： Automation Sensors citizen Weather Station Mesonet Rainfall Weather Variables

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Floristic composition and edaphic relationships in ferruginous campo rupestre reference ecosystems

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j.urnal of Mountain Science 2024年第3期21卷 719-733页

作者： G.Wilson FERNANDES Letícia RAMOS Dario c.PAIVA j.ssica cUNHA-BLUM Vanessa Matos GOMES Daniel NEGREIROS Ecologia Evolutiva&Biodiversidade Departamento de GenéticaEcologia e Evolução/ICBUniversidade Federal de Minas Gerais31270-901Belo HorizonteMGBrazil Knowledge center for Biodiversity 31270-901Belo HorizonteMGBrazil Department of Biological Sciences Institute of EnvironmentFlorida International UniversityMiamiFL 33199USA Programa de Pós Graduação em Biodiversidade e Uso dos Recursos Naturais Universidade Estadual de Montes ClarosMontes ClarosMGBrazil Laboratório de Estudo das Relações Solo-Planta Departamento de SolosUniversidade Federal Rural do Rio de JaneiroSeropédicaRGBrazil

Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the *** environments with high economic relevance,such as the ferruginous campo rupestre(rupestrian grassland known as canga in Brazil),are even more susceptible to severe impacts due to their extreme habitat conditions and low *** determination of reference ecosystems based on the intrinsic characteristics of the ecosystem is essential for conservation as well as to the implementation of ecological *** proposed the reference ecosystem of the three main types of habitats of the ferruginous campo rupestre based on their floristic *** described the floristic composition of each habitat and evaluated the physicochemical properties of the soils and the relationship between plants and *** three habitats showed high diversity of plant species and many endemic species,such as chamaecrista choriophylla,cuphea pseudovaccinium,Lychnophora pinaster,and Vellozia *** distribution of vegetation was strongly related with the edaphic characteristics,with a set of species more adapted to high concentration of base saturation,fine sand,organic carbon,and iron,while another set of species succeeded in more acidic soils with higher S and silt *** provide support for the contention that the ferruginous campo rupestre is a mosaic of different habitats shaped by intrinsic local *** to recognize the floristic composition of each particular habitat can lead to inappropriate restoration,increased habitat homogenization and increased loss of biodiversity and ecosystem *** study also advances the knowledge base for building the reference ecosystem for the different types of ferruginous campo rupestre habitats,as well as a key database for highlighting those species contribute most to community assembly in this diverse and threatened tropical mountain ecosystem.

关键词： canga Ecological restoration Extreme ecosystem Non-forest ecosystems Rupestrian grassland Taxon environment relationships

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In vivo measurement of NADH fluorescence lifetime in skeletal muscle via -ber-coupled time-correlated single photon counting

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j.urnal of Innovative Optical Health Sciences 2024年第1期17卷 121-134页

作者： Kathryn M.Priest j.cob V.Schluns Nathania Nischal colton L.Gattis j.ffrey c.Wolchok Timothy j.Muldoon Department of Biomedical Engineering University of Arkansas FayettevilleARUSA

Nicotinamide adenine dinucleotide(NADH)is a cofactor that serves to shuttle electrons during metabolic processes such as glycolysis,the tricarboxylic acid cycle,and oxidative phosphorylation(OXPHOS).NADH is autofluorescent,and itsfluorescence lifetime can be used to infer metabolic dynamics in living ***-coupled time-correlated single photon counting(TcSPc)equipped with an implantable needle probe can be used to measure NADH lifetime in vivo,enabling investigation of changing metabolic demand during muscle contraction or tissue *** study illustrates a proof of concept for point-based,minimally-invasive NADHfluorescence lifetime measurement in *** muscle loss(VML)inj.ries were created in the left tibialis anterior(TA)muscle of male Sprague Dawley *** lifetime measurements were collected before,during,and after a 30 s tetanic contraction in the inj.red and uninj.red TA muscles,which was subsequently-t to a biexponential decay model to yield a metric of NADH utilization(cytoplasmic vs protein-bound NADH,the A11/A22 ratio).On average,this ratio was higher during and after contraction in uninj.red muscle compared to muscle at rest,suggesting higher levels of free NADH in contracting and recovering muscle,indicating increased rates of *** inj.red muscle,this ratio was higher than uninj.red muscle overall but decreased over time,which is consistent with current knowledge of inflammatory response to inj.ry,suggesting tissue regeneration has *** data suggest that-ber-coupled TcSPc has the potential to measure changes in NADH binding in vivo in a minimally invasive manner that requires further investigation.

关键词： Glycolysis oxidative phosphorylation energy metabolism volumetric muscle loss

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