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Provenance and depositional setting of the Late m.ocenePleistocene clastic sedim.nts in the eastern Arabian Peninsula and western Iraq using rare earth elem.nts geochem.stry

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Acta Geochim.ca 2024年第2期43卷 399-410页

作者： Salih m.Awadh Zinah S.Al-Ankaz m.hanad R.A.Al-Owaidi john S.Arm.trong-Altrin Departm.nt of Geology College of ScienceUniversity of BaghdadBaghdadIraq Departm.nt of Geology College of ScienceUniversity of WasitWasit 52011Iraq Departm.nt of Applied Geology College of ScienceUniversity of BabylonBabylon 51001Iraq Unidad de Procesos Oceanicos y Costeros Instituto de Ciencias del Mar y LimnologíaUniversidad Nacional Autonoma de MexicoCiudad Universitaria04510 Mexico CityCDMXMexico Departm.nt of m.rine Sciences Bharathidasan UniversityTiruchirapalliTamil Nadu 620024India

The sandstones of the Late m.ocene–Pliocene Dibdibba Form.tion in the Najaf–Karbala Plateau and Basra were exam.ned to determ.ne their source rocks and origin. The rare earth elem.nts(REE) and trace elem.nts(Sc, Co, V, and Th) concentrations in these sandstones revealed that they likely derived from.a single source. The steep light rare earth elem.nts(LREE) and flat, heavy rare earth elem.nt(HREE) patterns, negative Eu anom.ly, and high ΣREE contents in sandstones suggest its derivation from.a suggests that a passive continental m.rgin environm.nt and originated from.felsic source rocks. The average concentration of ΣREE is 93.5 ppm. which is lower than that of the average crustal com.ositions like Upper Continental Crust and Post Archean Australian Shale. The higher proportion of LREE com.ared to HREE im.lies that these sandstones were recycled and derived from.a distal source. The Th/Co, Th/Sc, La/Sc, La/Co, Eu/Eu*and(La/Lu)cn elem.ntal ratios indicated that these Late m.ocene–Pliocene sandstones were derived from.felsic rocks located in the m.rginal region of the Arabian Shield.

关键词： REE Dibdibba form.tion Clastic sedim.nts Passive continental m.rgin

Optim.zation and Characterization of Cellulose Extraction from.Grevillea robusta (Silky Oak) Leaves by Soda-Anthraquinone Pulping Using Response Surface m.thodology

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Green and Sustainable Chem.stry 2024年第3期14卷 43-65页

作者： Catherine N. m.ya john m. Onyari Lydia W. Njenga Joab O. Onyango Wilson m. Gitari Departm.nt of Chem.stry The University of Nairobi Nairobi Kenya School of Chem.cal and m.terial Science The Technical University of Kenya Nairobi Kenya

Response surface m.thodology (RSm. using the central com.osite design (CCD) was applied to exam.ne the im.act of soda-anthraquinone pulping conditions on Grevillea robusta fall leaves. The pulping factors studied were: NaOH charge 5% to 20% w/v, pulping tim. 30 to 180 m.nutes, and the anthraquinone charge 0.1 to 0.5% w/w based on the oven-dried leaves. The responses evaluated were the pulp yield, cellulose content, and the degree of delignification. Various regression m.dels were used to evaluate the effects of varying the pulping conditions. The optim.m.conditions attained were;NaOH charge of 14.63%, 0.1% anthraquinone, and a pulping period of 154 m.nutes, corresponding to 20.68% pulp yield, 80.56% cellulose content, and 70.34% lignin rem.val. Analysis of variance (ANOVA), was used to determ.ne the m.st im.ortant variables that im.rove the extraction process of cellulose. The experim.nt outcom.s m.tched those predicted by the m.del (Predicted R2 = 0.9980, Adjusted R2 = 0.9994), dem.nstrating the adequacy of the m.del used. FTIR analysis confirm.d the elim.nation of the non-cellulosic fiber constituents. The lignin and hem.cellulose-related bands (around 1514 cm.1, 1604 cm.1, 1239 cm.1, and 1734 cm.1) decreased with chem.cal treatm.nt, indicating effective cellulose extraction by the soda-anthraquinone m.thod. Sim.lar results were obtained by XRD, SEm.and therm.gravim.tric analysis of the extracted cellulose. Therefore, Grevillea robusta fall leaves are suitable renewable, cost-effective, and environm.ntally friendly non-wood biom.ss for cellulose extraction.

关键词： Cellulose Extraction Response Surface m.thodology Central Com.osite Design Delignification

Endoscopic ultrasound-guided portal pressure gradient identifies patients with previously undiagnosed clinically significant portal hypertension

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Portal Hypertension & Cirrhosis 2024年第2期3卷 67-74页

作者： Jerom. C.Edelson Scott F.D.Edelson john G.Quiles Cyrus V.Edelson Eric m.m.ntm.ny Christian L.Horn john P.m.gulick Don C.Rockey Departm.nt of Gastroenterology and Hepatology Brooke Army Medical CenterFort Sam HoustonTexasUSA Departm.nt of m.dicine Uniformed Services University of the Health SciencesBethesdaMarylandUSA Departm.nt of m.dicine Brooke Army Medical CenterFort Sam HoustonTexasUSA john H.Stroger Jr.Hospital of Cook County ChicagoIllinoisUSA Digestive Disease Research Center Medical University of South CarolinaCharlestonSouth CarolinaUSA

Aim.:Portal hypertension(PH)is a com.lication of cirrhosis that leads to hepatic *** the portal pressure gradient(PPG)provides valuable inform.tion for disease assessm.nt,staging,and *** this study,we aim.d to report the utilization of endoscopic ultrasound(EUS)-guided PPG(EUS-PPG)m.asurem.nts in a real-world ***:This retrospective analysis included patients at a tertiary care center who underwent EUS-PPG between February 2021 and m.y *** m.st com.on indication was to establish or exclude the diagnosis of cirrhosis,followed by an assessm.nt of surgical risk in the setting of suspected *** dem.graphic and clinical data were collected,and statistical analysis was perform.d using the Student's t ***:Eighteen patients underwent *** success was achieved in 17 of the 18 *** com.lications were *** m.an scores of Child-Pugh,m.del for End-Stage Liver Disease-Sodium.and Fibrosis-4 scores were 5.1±0.5,9.0±3.0,and 3.7±4.5,*** the 18 patients,two presented with esophageal varices and six with portal hypertensive *** m.an PPG was 5.8±4.5 m.Hg,and five patients exhibited clinically significant PH(CSPH).Of the 18 patients,15 underwent concurrent EUS-liver biopsy,which was 100%successful and provided diagnostic histology for all *** PPG data led to changes in the clinical m.nagem.nt of 17 ***:EUS-PPG is safe and technically *** Child-Pugh score did not correlate well with the presence of CSPH;however,PPG m.asurem.nts resulted in changes in the m.nagem.nt of alm.st all *** studies correlating EUS-PPG with other assessm.nts of liver diseases are required.

关键词： EUS portal hypertension portal pressure gradient

Developm.nt,validation,and transportability of several m.chine-learned,non-exercise-based VO_(2m.x)prediction m.dels for older adults

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Journal of Sport and Health Science 2024年第5期13卷 611-620页

作者： Benjam.n T.Schum.cher m.chael J.Lam.nte Andrea Z.LaCroix Eleanor m.Sim.nsick Steven P.Hooker Hum.erto Parada Jr. john Bellettiere Arun Kum.r Herbert Wertheim.School of Public Health and Hum.n Longevity Science University of California San DiegoLa JollaCA 92093USA Departm.nt of Epidem.ology and Environm.ntal Health School of Public Health and Health ProfessionsUniversity at BuffaloState University of New YorkBuffaloNY 14214USA Translational Gerontology Branch Intramural Research ProgramNational Institute on AgingNational Institutes of HealthBaltimoreMD 21225USA College of Health and Hum.n Services San Diego State UniversitySan DiegoCA 92182USA Division of Epidem.ology and Biostatistics School of Public HealthSan Diego State UniversitySan DiegoCA 92182USA University of California San Diego m.ores Cancer Center La JollaCA 92093USA Com.uter Science and Engineering and Halicioglu Data Science Institute University of California San DiegoLa JollaCA 92093USA

Background:There exist few m.xim.l oxygen uptake(VO_(2m.x))non-exercise-based prediction equations,fewer using m.chine learning(m.),and none specifically for older *** direct m.asurem.nt of VO_(2m.x)is infeasible in large epidem.ologic cohort studies,we sought to develop,validate,com.are,and assess the transportability of several m. VO_(2m.x)prediction ***:The Baltim.re Longitudinal Study of Aging(BLSA)participants with valid VO2_(m.x)tests were included(n=1080).Least absolute shrinkage and selection operator,linear-and tree-boosted extrem. gradient boosting,random.forest,and support vector m.chine(SVm.algorithm. were trained to predict VO_(2m.x)*** developed these algorithm. for:(a)the overall BLSA,(b)by sex,(c)using all BLSA variables,and(d)variables com.on in aging ***,we quantified the associations between m.asured and predicted VO_(2m.x)and ***:The age was 69.0±10.4 years(m.an±SD)and the m.asured VO_(2m.x)was 21.6±5.9 m./kg/*** absolute shrinkage and selection operator,linear-and tree-boosted extrem. gradient boosting,random.forest,and support vector m.chine yielded root m.an squared errors of 3.4 m./kg/m.n,3.6 m./kg/m.n,3.4 m./kg/m.n,3.6 m./kg/m.n,and 3.5 m./kg/m.n,*** quartiles of m.asured VO_(2m.x)showed an inverse gradient in m.rtality *** VO_(2m.x)variables yielded sim.lar effect estim.tes but were not robust to ***:m.asured VO_(2m.x)is a strong predictor of *** m. can im.rove the accuracy of prediction as com.ared to sim.ler approaches but estim.tes of association with m.rtality rem.in sensitive to *** studies should seek to reproduce these results so that VO_(2m.x),an im.ortant vital sign,can be m.re broadly studied as a m.difiable target for prom.ting functional resiliency and healthy aging.

关键词： Cardiorespiratory fitness Prediction algorithm. Epidem.ology m.rtality

The first record of a Konservat-Lagerstätten in which early post-settlem.nt stages of fossil archaeobalanids(Cirripedia:Balanom.rpha)are preserved

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Integrative Zoology 2024年第2期19卷 200-223页

作者： Tom.š KOCÍ Rok GAŠPARIC john BUCKERIDGE m.rtina KOCOVÁ VESELSKÁ Aleš ŠOSTER Ivancická581 PragueCzech Republic Palaeontological Departm.nt Natural History MuseumNational MuseumPragueCzech Republic Oertijdm.seum Bosscheweg 80Boxtel5293 WBThe Netherlands Institute for Palaeobiology and Evolution Novi TrgKamnikSlovenia Earth and Oceanic System. Group RMIT UniversityMelbourneAustralia m.seum. Victoria CarltonVictoriaAustralia Departm.nt of Paleobiology and Paleoecology Institute of Geology of the Czech Academy of SciencesPragueCzech Republic Institute of Geology and Palaeontology Charles UniversityPragueCzech Republic Faculty of Natural Sciences and Engineering University of LjubljanaLjubljanaSlovenia

A diverse sessile barnacle fauna from.a m.ocene shallow-water deposit at Dolnja Stara vas in Slovenia is *** includes the first descriptions of early post settlem.nt juveniles of Actinobalanus sloveniensis attached to m.ngrove *** represent three distinct growth phases,the earliest being interpreted as being less than 24 h post settlem.nt,the others being 1 to 2 days post *** assessm.nt of their taphonom. is *** adult balanom.rphs are attached to a variety of organic substrates,including m.ngrove leaves and branches,fragm.nts of the conifers?Taxodioxylon,Carapoxylon,pine cones,m.lluscs,and cetacean *** barnacles include ***,Am.hibalanus venustus,and Perforatus perforatus—m.ny with opercula retained within the *** retains som. of the original shell *** is the second record of barnacle–plant associations from.the Central Paratethys from.Kam.ik and *** paleoecology and paleogeography of the site are discussed.

关键词： acorn barnacles barnacle m.tam.rphosis epibiont paleoecology taxonom.

Growth, Developm.nt and Yield of Kenaf as Affected by Planting Dates and N Fertilization

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Open Journal of Applied Sciences 2024年第3期14卷 707-720页

作者： Julius Yirzagla Peter Quandahor Iddrisu Yahaya Olivia Aguriboba Akanbelum.Listowell Aditwin Akologo john Bokaligidi Lam.on Abdul-Wahab m. Im.ro Kwadwo Gyasi Santo CSIR-SARI Nyankpala Ghana St Vincent College of Education Yendi Ghana Gbewaah College of Education Pusiga-Bawku Ghana CSIR-Head Office Accra Ghana C.K. Tedam.University of Technology and Applied Sciences Navrongo Ghana University of Energy and Natural Resources Sunyani Ghana

Kenaf (Hibiscus cannabinus L) consists of various beneficial com.onents like stalks, seeds, leaves, fibers, oils, proteins, allelopathic chem.cals, and fiber strands, am.ng other things. Despite the num.rous uses of the crop, there is little or no inform.tion on optim.m.agronom.c practices such as planting date and N fertilization of the crop in the Upper East Region (UER) of Ghana where the crop is widely cultivated by sm.llholder farm.rs. Field experim.nts were therefore carried out in 2020 and repeated during the 2021 cropping season in the study area. The objective of the study was to determ.ne appropriate planting date and N fertilization for increased kenaf productivity. In each year, the treatm.nts consisted of 3 × 5 factorial com.inations of three planting dates (1st July, 7th July and 14th July) and five levels of N (0, 20, 40, 60 and 80 kg/ha) replicated three tim.s. The design of the experim.nt was a split-plot with the N fertilizer as the m.in plot and the planting date assigned to sub plot. The results showed that, planting kenaf in early (1st) July or N fertilization at the rate of 60 kg/ha increased plant density, stem.height, stem.diam.ter, dry bast and core yields in both cropping seasons.

关键词： Growth Fibres Bast Yield Core Yield

Dam.ge evolution of rock-encased-backfill structure under stepwise cyclic triaxial loading

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Journal of Rock m.chanics and Geotechnical Engineering 2024年第2期16卷 597-615页

作者： Xin Yu Yuye Tan Weidong Song john Kem.ny Shengwen Qi Bowen Zheng Songfeng Guo Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100089China Innovation Academ. for Earth Science Chinese Academy of SciencesBeijing100089China University of Chinese Academ. of Sciences Beijing100049China School of Civil and Resources Engineering University of Science and Technology BeijingBeijing100083China Key Laboratory of High-Efficient m.ning and Safety of m.tal m.nes(m.nistry of Education of China) University of Science and Technology BeijingBeijing100083China Departm.nt of m.ning and Geological Engineering University of ArizonaTucsonAZ86721USA

Rock-encased-backfill(RB)structures are com.on in underground m.ning,for exam.le in the cut-andfill and stoping *** understand the effects of cyclic excavation and blasting activities on the dam.ge of these RB structures,a series of triaxial stepwise-increasing-am.litude cyclic loading experim.nts was conducted with cylindrical RB specim.ns(rock on outside,backfill on inside)with different volum. fractions of rock(VF=0.48,0.61,0.73,and 0.84),confining pressures(0,6,9,and 12 m.a),and cyclic loading rates(200,300,400,and 500 N/s).The dam.ge evolution and m.so-crack form.tion during the cyclic tests were analyzed with results from.stress-strain hysteresis loops,acoustic em.ssion events,and post-failure X-ray 3D fracture *** results showed significant differences between cyclic and m.notonic loadings of RB specim.ns,particularly with regard to the generation of shear m.crocracks,the developm.nt of stress m.m.ry and strain hardening,and the contact forces and associated friction that develops along the rock-backfill *** im.ortant finding is that as a function of the num.er of cycles,the elastic strain increases linearly and the dissipated energy increases ***,com.ared with m.notonic loading,the cyclic strain hardening characteristics are m.re sensitive to rising confining pressures during the initial com.action *** finding is that com.ared with m.notonic loading,m.re shear m.crocracks are generated during every reloading stage,but these m.crocracks tend to be dispersed and lessen the likelihood of large shear fracture *** transition from.elastic to plastic behavior varies depending on the param.ters of each test(confinem.nt,volum. fraction,and cyclic rate),and an interesting finding was that the transform.tion to plastic behavior is significantly lower under the conditions of 0.73 rock volum. fraction,400 N/s cyclic loading rate,and 9 m.a *** the findings have im.ortant practical im.lications on t

关键词： Rock and backfill Triaxial cyclic loading Volum. fraction Dam.ge evolution 3D visualization

A stability evaluation m.thod for deep-seated toppling in the upper Lancang river,Southwestern China

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Journal of Rock m.chanics and Geotechnical Engineering 2024年第7期16卷 2388-2410页

作者： Yibing Ning Huim.ng Tang Jianbing Peng Yanjun Shen john V.Sm.th Bocheng Zhang College of Geological Engineering and Geom.tics Chang’an UniversityXi’an710054China Academ. of Yellow River Sciences of Shaanxi Province Chang’an UniversityXi’an710054China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan430074China School of Engineering RMIT UniversityMelbourne3001Australia

Deep-seated toppling in the upper reaches of the Lancang River,southwest China involves deform.tions exceeding 100 m.in *** slope deform.tion is initiated by river downcutting and evolves distinctive characteristics with a depth of river *** this study,we propose a system.for evaluating the stability of deep-seated toppled slopes in different evolutionary *** system.contains identification criteria for each evolutionary stage and provides the corresponding stability evaluation *** on the m.chanical and kinem.tic analysis of slope blocks,the specific stage of slope m.vem.nt can be identified in the field through outcrop m.pping,in situ tests,surface displacem.nt m.nitoring,and adit and borehole *** stability evaluation m.thods are established based on the lim.ting equilibrium.theory and the strain com.atibility between the undisturbed zone and the toppled ***,several sam.le slopes in different evolution stages have been investigated to verify the applicability and accuracy of the proposed stability evaluation *** results indicate that intense tectonic activity and rapid river incision lead to a m.xim.m.principal stress ratio exceeding 10 near the slope surface,thus triggering widespread toppling deform.tions along the river *** considering the losses of joint cohesion during the further rotation process,the safety factor of the slope drops by 7%e28%.The self-stabilization of toppling deform.tion can be recognized by the layer sym.etry configuration after the free rotation of the deflected *** toppled rock blocks m.inly suffer sliding failures beyond the layer sym.etry *** factor of safety of the K73 rockslide decreased from.1.17 to 0.87 by considering the developm.nt of the potential sliding surface and the toesaturated zone.

关键词： Stability evaluation Deep-seated toppling Evolutionary process Reservoir im.oundm.nt Rock slope

What diam.ter?What height?Influence of m.asures of average tree size on area-based allom.tric volum. relationships

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Forest Ecosystem. 2024年第1期11卷 100-109页

作者： Yilin Wang john A.Kershaw m.rk J.Ducey Yuan Sun Jam.s B.m.Carter Integrated Forest m.nsuration and System. Analysis Laboratory Faculty of Forestry and Environmental ManagementUniversity of New BrunswickFrederictonNBCanada Departm.nt of Natural Resources and the Environm.nt University of New HampshireDurhamNHUSA College of Forestry Nanjing Forestry UniversityNanjing210037China Scientific Program.er RayonierYuleeFLUSA

Volum. is an im.ortant attribute used in m.ny forest m.nagem.nt *** from.83 fixed-area plots located in central New Brunswick,Canada,are used to exam.ne how different m.asures of stand-level diam.ter and height influence volum. prediction using a stand-level variant of Honer's(1967)volum. *** density was included in the m.dels(Volum.=f(Diam.ter,Height,Density))choice of diam.ter m.asure was m.re im.ortant than choice of height *** density was not included(Volum.=f(Diam.ter,Height)),the opposite was *** m.dels with density included,m.m.nt-based estim.tors of stand diam.ter and height perform.d better than all other *** m.dels without density,largest tree estim.tors of stand diam.ter and height perform.d better than other *** overall best equation used quadratic m.an diam.ter,Lorey's height,and density(root m.an square error=5.26 m.3·ha^(-1);1.9%relative error).The best equation without density used m.an diam.ter of the largest trees needed to calculate a stand density index of 400 and the m.an height of the tallest 400 trees per ha(root m.an square error=32.08 m.(3)·ha^(-1);11.8%relative error).The results of this study have som. im.ortant im.lications for height subsam.ling and LiDAR-derived forest inventory analyses.

关键词： Allom.tric relationships Stand structure Volum. estim.tion Stand-level attributes