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Open Journal of Geology 2024年第3期14卷 279-297页

作者： mahamadou diallo mamadou Yossi Ibrahim méyès Coulibaly Youssouf son Amako dolo département de Géologie et mines Ecole Nationale d’Ingénieurs Abderhamane Baba Touré (ENI-ABT) Bamako Mali sagax Afrique s.A Geophysical surveys and Consulting Bamako Mali

The dialafara area is part of the highly endowed Kédougou-Kéniéba Inlier (KKI), West-malian gold belt, which corresponds to a Paleoproterozoic window through the West African Craton (WAC). This study presents, first of all, an integration of geophysical data interpretation with litho-structural field reconnaissance and then proposes a new litho-structural map of the dialafara area. The dialafara area shows a variety of lithology characterized by volcanic and volcano-sedimentary units, metasediments and plutonic intrusion. These lithologies were affected by a complex superposition of structures of unequal importance defining three deformation phases (dsub>d1sub> to dsub>d3sub>) under ductile to brittle regimes. These features permit to portray a new litho-structural map, which shows that the dialafara area presents a more complex lithological and structural context than the one presented in regional map of the KKI. This leads to the evidence that this area could be a potential site for exploration as it is situated between two world-class gold districts.

关键词： Kédougou-Kéniéba Inlier dialafara mapping Aeromagnetic data structure

Additively manufactured Ti–Ta–Cu alloys for the next-generation load-bearing implants

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International Journal of Extreme manufacturing 2024年第1期6卷 353-374页

作者： Amit Bandyopadhyay Indranath mitra sushant Ciliveri Jose d Avila William dernell stuart B Goodman susmita Bose W.m.Keck Biomedical materials Research Laboratory School of Mechanical and Materials EngineeringWashington State UniversityPullmanWA 99164United States of America Veterinary Clinical sciences College of Veterinary MedicineWashington State UniversityPullmanWA 99164United States of America department of Orthopedic surgery Stanford University Medical CenterRedwood CityCA 94063United States of America

Bacterial colonization of orthopedic implants is one of the leading causes of failure and clinical complexities for load-bearing metallic implants. Topical or systemic administration of antibiotics may not offer the most efficient defense against colonization, especially in the case of secondary infection, leading to surgical removal of implants and in some cases even limbs. In this study, laser powder bed fusion was implemented to fabricate Ti3Al2V alloy by a 1:1 weight mixture of CpTi and Ti6Al4V powders. Ti-Tantalum(Ta)–Copper(Cu) alloys were further analyzed by the addition of Ta and Cu into the Ti3Al2V custom alloy. The biological,mechanical, and tribo-biocorrosion properties of Ti3Al2V alloy were evaluated. A 10 wt.% Ta(10Ta) and 3 wt.% Cu(3Cu) were added to the Ti3Al2V alloy to enhance biocompatibility and impart inherent bacterial resistance. Additively manufactured implants were investigated for resistance against Pseudomonas aeruginosa and staphylococcus aureus strains of bacteria for up to 48 h. A 3 wt.% Cu addition to Ti3Al2V displayed improved antibacterial efficacy, i.e.78%–86% with respect to CpTi. mechanical properties for Ti3Al2V–10Ta–3Cu alloy were evaluated, demonstrating excellent fatigue resistance, exceptional shear strength, and improved tribological and tribo-biocorrosion characteristics when compared to Ti6Al4V. In vivo studies using a rat distal femur model revealed improved early-stage osseointegration for alloys with10 wt.% Ta addition compared to CpTi and Ti6Al4V. The 3 wt.% Cu-added compositions displayed biocompatibility and no adverse infammatory response in vivo. Our results establish the Ti3Al2V–10Ta–3Cu alloy’s synergistic effect on improving both in vivo biocompatibility and microbial resistance for the next generation of load-bearing metallic implants.

关键词： Ti6Al4V load-bearing implants additive manufacturing 3d printing antibacterial performance

Abalone shell-derived mg-doped mesoporous hydroxyapatite microsphere drug delivery system loaded with icariin for inducing apoptosis of osteosarcoma cells

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Biomaterials Translational 2024年第2期5卷 185-196页

作者： Liu K. Cheng m. Huang H. Yu H. Zhao s. Zhou J. Tie d. Wang J. Pan P. Chen J. marine College Shandong University Shandong Province Weihai China state Key Laboratory of mineral Processing Beijing China College of Biological science and Technology Fuzhou University Fujian Province Fuzhou China

Hydroxyapatite (HAP) porous microspheres with very high specific surface area and drug loading capacity, as well as excellent biocompatibility, have been widely used in tumour therapy. mg2+ is considered to be a key factor in bone regeneration, acting as an active agent to stimulate bone and cartilage formation, and is effective in accelerating cell migration and promoting angiogenesis, which is essential for bone tissue repair, anti-cancer, and anti-infection. In this study, abalone shells from a variety of sources were used as raw materials, and mg2+-doped abalone shell-derived mesoporous HAP microspheres (mg-HAP) were prepared by hydrothermal synthesis as mg2+/icariin smart dual delivery system (ICA-mg-HAP, ImHA). With increasing of mg2+ doping, the surface morphology of HAP microspheres varied from collapsed macroporous to mesoporous to smooth and non-porous, which may be due to mg2+ substitution or coordination in the HAP lattice. At 30% mg2+ doping, the mg-HAP microspheres showed a more homogeneous mesoporous morphology with a high specific surface area (186.06 m2/g). The ImHA microspheres showed high drug loading (7.69%) and encapsulation rate (83.29%), sustained mg2+ release for more than 27 days, sustained and stable release of icariin for 60 hours, and good responsiveness to pH (pH 6.4 > pH 5.6). In addition, the ImHA delivery system stimulated the rapid proliferation of bone marrow mesenchymal stem cells and induced apoptosis in mG63 cells by blocking the G2 phase cycle of osteosarcoma cells and stimulating the high expression of apoptotic genes (Bcl-2, caspase-3,-8,-9). This suggests that the abalone shell-based ImHA may have potential applications in drug delivery and tumour therapy. © 2024, Chinese medical multimedia Press Co Ltd. All rights reserved.

关键词： abalone shell drug delivery hydroxyapatite microspheres magnesium doping osteosarcoma

Biotransformation of 6:2 fluorotelomer sulfonate(6:2 FTs)in sulfur-rich media by Trametopsis cervina

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Frontiers of Environmental science & Engineering 2024年第9期18卷 17-26页

作者： Felix Grimberg Thomas m Holsen sujan Fernando siwen Wang department of Civil and Environmental Engineering Clarkson UniversityPotsdamNew York 13699USA

Biotransformation of 6:2 fluorotelomer sulfonate(6:2 FTs)by two species of white-rot fungi,Pleurotus ostreatus(***)and Trametopsis cervina(***),was investigated in a sulfurrich medium designed to stimulate production of lignin-degrading *** of 6:2 FTs was observed by *** over the study period of 30 d,but not by *** rates were comparable to those found in other studies investigating mixed culture degradation in nonsulfur limiting media,with approximately 50 mol%of applied 6:2 FTs removed after 30 *** transformation products were short-chain perfluorocarboxylic acids(PFCAs),including PFHxA(2.27 mol%),PFPeA(0.24 mol%),and PFBA(0.28 mol%).The main intermediate products include 5:2 sFTOH(16.3 mol%)and 5:3 FTCA(2.99 mol%),while 6:2 FTCA,6:2 FTuCA,and 5:2 ketone were also identified at low *** 60 mol%of detected products were assigned to the major pathway to 5:2 ketone,and 40 mol%were assigned to the minor pathway to 5:3 *** overall molar balance was found to decrease to 75 mol%by day 30,however,was closed to near 95 mol%with a theoretical estimation for the volatile intermediates in the headspace,5:2 ketone and 5:2 *** different capabilities of the two white-rot fungal species for 6:2 FTs biotransformation in sulfur-rich media suggest that the enzyme processes of *** to de-sulfonate 6:2 FTs may be unrelated to sulfur metabolism.

关键词： White-rot fungus 6:2 fluorotelomer sulfonate(6:2 FTs) Biotransformation sulfur-rich medium Intermediate products

solar-driven CO_(2) conversion to methane and methanol using different nanostructured Cu_(2)O-based catalysts modified with Au nanoparticles

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Journal of Energy Chemistry 2024年第4期91卷 287-298页

作者： João Angelo Lima Perini Lilian d.moura Torquato Juliana Fde Brito Gustavo A.Andolpho mateus A.Gonçalves Leonardo d.de Angelis Lucas d.Germano susana I.Córdoba de Torresi Teodorico C.Ramalho maria V.Boldrin Zanoni são Paulo state University(UNEsP) Institute of ChemistryRua Prof.Francisco Degni55AraraquaraSP 14800-060Brazil National Institute of Alternative Technologies for detection Toxicological Evaluation and Removal of Micropollutants and Radioactive Substances(INCT-DATREM)São Paulo State University(UNESP)Institute of ChemistryRua Prof.Francisco Degni55AraraquaraSP 14800-060Brazil Laboratory of molecular modelling Department of ChemistryNatural Sciences InstituteFederal University of LavrasLavrasMG 37200-900Brazil department of Chemistry Faculty of ScienceUniversity of Hradec KrálovéHradec Králové50003Czech Republic Instituto de Química Universidade de São PauloAv.Prof.Lineu Prestes 74805508-080São PauloSPBrazil

This work describes the use of TiO_(2)nanotubes-based electrodes(TNT)modified with Cu_(2)O nanostructures and gold nanoparticles for the photoelectroreduction of CO_(2)to produce value-added compounds.A thin layer of polydopamine was used as both an adherent agent and an electron transfer mediator,due to itsπ-conjugated electron *** highest production yield was achieved using a TNT@PdA/Nc/Au40%electrode,with Faradaic efficiencies of 47.4%(110.5μm cm^(-2))and 27.8%(50.4μm cm^(-2))for methanol and methane,*** performance of the photoelectrodes was shown to be Cu_(2)O facet-dependent,with cubic structures leading to greater conversion of CO_(2)to methanol(43%)and methane(27%),compared to the octahedral morphology,while a higher percentage of metallic gold on the nanostructured Cu_(2)O surface was mainly important for *** functional theory(dFT)calculations supported these findings,attributing the superior photoelectrocatalytic performance of the TNT@PdA/Nc/Au40%electrode for CH4generation to the formation of an OCH3intermediate bonded to Au *** using isotope-labeling and analysis by gas chromatograph-mass(GC-ms)demonstrated that13CO_(2)was the source for photoelectrocatalytic generation of13CH3OH and13CH313CH2OH.

关键词： Cu_(2)O nanocubes Photoelectrocatalysis Polydopamine CO_(2) photoelectroreduction dFT calculations

Analysis of synthetic parameters for coating aluminum powders with phenyltriethoxysilane coupling agent and their effects on powder flow behavior

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Particuology 2024年第7期90卷 412-417页

作者： Lillian m.mawby Bellamarie Ludwig Benjamin J.Lear department of Chemistry The Pennsylvania State UniversityUniversity ParkPA16802USA Applied Research Laboratory The Pennsylvania State UniversityUniversity ParkPA16802USA

Though silanization of aluminum powder is currently used to improve its flow properties,for use as an alternative fuel source,there are a wide range of experimental parameters for the process and not all of them have been thoroughly *** this is complete,it is unknown if the process is optimized in terms of time,efficiency,and ***,we report on a study into the effects of changes in humidity,degree of agitation,reaction temperature,and curing time upon the deposition of phenyl triethoxysilane into 20μm(d50)aluminum *** confirm the deposition of the coating via diffuse reflectance infrared spectroscopy and x-ray photoelectron *** then characterize the coated particles using apparent density measurements and Carney flow *** analysis of variance,we find that,of the parameters explored,only changes in cure time and reaction temperature provide meaningful changes to the apparent density,while none of our parameters produced statistically significant changes in Carney flow ***,we conclude that,when optimizing silanization of aluminum particles,environmental control of humidity is unneeded and that the reaction can be run with minimal *** ability to largely ignore these parameters is a benefit to large-scale processing.

关键词： Aluminum powder silane Fluidization Apparent density Carney flow

Effect of biochar on the metabolome of soybean seedlings

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Oil Crop science 2024年第1期9卷 60-68页

作者： Nathalia E.silva mariana G.Aguilar Osania E.Ferreira Gleicia m.Paulino Jaqueline C.L.Carvalho Lúcia P.s.Pimenta Alan R.T.machado Programa de Pos-graduaçao em Ciencias Ambientais Universidade do Estado de Minas GeraisFrutalMinas Gerais38202-436Brazil departamento de Química Universidade Federal de Minas GeraisMinas GeraisBelo Horizonte31270-901Brazil departamento de Engenharia Aplicada e Tecnologias Ambientais Universidade do Estado de Minas GeraisJoao MonlevadeMinas Gerais35930-314Brazil departamento de Ciencias Exatas Universidade do Estado de Minas GeraisJoao MonlevadeMinas Gerais35930-314Brazil

The use of biochar can have several effects on plant germination,depending on raw material,preparation method and application ***,the molecular mechanisms that lead to those results have yet to be *** aim of this research was to improve the understanding of these mechanisms by characterizing the metabolic effects of sugarcane ba.a.se biochar on soybean *** types of biochars were prepared by pyrolysis at 300℃(sCB300),400℃(sCB400)and 600℃(sCB600).Then,each one was mixed into sand at 1%,3%,5%(w/w)dose,*** experiment was performed in 8 days of incubation,when the number of germinated seeds and the average radicle length were *** evaluate the metabolome,the dry biomass(dB)was subjected to extraction with a mixture of methanol-d4 and d2O(1:1 v/v).The extracts were submitted to metabolomics analysis by Proton Nuclear magnetic *** Relative Germination,Relative Average Radicle Growth and Germination Index increased in all treatments compared to *** the other hand,the dB increased in all treatments,except for sCB300,at doses of 1%and 3%w/*** metabolites(alanine,asparagine,acetic acid,citric acid,glycerol,fatty acids and sucrose)were identified and quantified in dB extracts as the most influential finding for the separation of *** together,these results strongly suggested that biochars accelerated the catabolism of triacylglycerols to sucrose and induced a slight osmotic stress.

关键词： Germination metabolomics 1H NmR Pyrolysis sugarcane ba.a.se

Older Adult Compendium of Physical Activities:Energy costs of human activities in adults aged 60 and older

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Journal of sport and Health science 2024年第1期13卷 13-17,F0003页

作者： Erik A.Willis stephen d.Herrmann mary Hastert Chelsea L.Kracht Tiago V.Barreira John m.schuna Jr. Zhenghua Cai minghui Quan scott A.Conger Wendy J.Brown Barbara E.Ainsworth Center for Health Promotion and disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA Kansas Center for metabolism and Obesity Research The University of Kansas Medical CenterKansas CityKS 66160USA division of Physical Activity and Weight management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Clinical science division Pennington Biomedical Research CenterBaton RougeLA 70808USA Exercise science department Syracuse UniversitySyracuseNY 13244USA school of Exercise&sport science Oregon State UniversityCorvallisOR 97331USA school of Exercise and Health Shanghai University of SportShanghai 200438China department of Kinesiology Boise State UniversityBoiseID 83725USA school of Human movement and Nutrition sciences The University of QueenslandSt.LuciaQLD 4072Australia Faculty of Health sciences and medicine Bond UniversityGold CoastQLD 4229Australia College of Health solutions Arizona State UniversityPhoenixAZ 85003USA

Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).methods:Physical activities(PAs)and their metabolic equivalent of task(mET)values were obtained from a systematic search of studies published in 4 sport and exercise databases(Pubmed,Embase,sPORTdiscus(EBsCOhost),and scopus)and a review of articles included in the 2011 Adult Compendium that measured PA in older *** values were computed as the oxygen cost(VO_(2),mL/kg/min)during PA divided by 2.7 m L/kg/min(mET_(60+))to account for the lower resting metabolic rate in older ***:We identified 68 articles and extracted energy expenditure data on 427 *** these,we derived 99 unique specific Activity codes with corresponding mET_(60+)values for older *** developed a website to present the OA Compendium mET_(60+)values:https://***:The OA Compendium uses data collected from adults>60 years for more accurate estimation of the energy cost of PAs in older *** is an accessible resource that will allow researchers,educators,and practitioners to find mET_(60+)values for older adults for use in PA research and practice.

关键词： Energy expenditure Exercise mET Older adults

An Iterative Relaxation Approach to the solution of the Hamilton-Jacobi-Bellman-Isaacs Equation in Nonlinear Optimal Control

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IEEE/CAA Journal of Automatica sinica 2018年第1期5卷 360-366页

作者： m.d.s.Aliyu department of Electrical Engineering King Faisal University Al-Ahsa 31982 Saudi Arabia IEEE

In this paper, we propose an iterative relaxation method for solving the Hamilton-Jacobi-Bellman-Isaacs equation(HJBIE) arising in deterministic optimal control of affine nonlinear systems. Local convergence of the method is established under fairly mild assumptions, and examples are solved to demonstrate the effectiveness of the method. An extension of the approach to Lyapunov equations is also discussed. The preliminary results presented are promising, and it is hoped that the approach will ultimately develop into an efficient computational tool for solving the HJBIEs.

关键词： Affine nonlinear system bounded continuous function convergence Hamilton-Jacobi-Bellman-Isaacs equation Lyapunov equation relaxation method Riccati equation

Aging impairs the osteocytic regulation of collagen integrity and bone quality

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Bone Research 2024年第1期12卷 78-94页

作者： Charles A.schurman serra Kaya Neha dole Nadja m.maldonado Luna Natalia Castillo Ryan Potter Jacob P.Rose Joanna Bons Christina d.King Jordan B.Burton Birgit schilling simon melov simon Tang Eric schaible Tamara Alliston department of Orthopaedic surgery University of CaliforniaSan FranciscoCA 94143USA UC Berkeley/UCsF Graduate Program in Bioengineering San FranciscoCA 94143USA Buck Institute for Research on Aging NovatoCA 94945USA Washington University in st Louis Department of OrthopedicsSt.LouisMO 63130USA Advanced Light source Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

Poor bone quality is a major factor in skeletal fragility in elderly *** molecular mechanisms that establish and maintain bone quality,independent of bone mass,are unknown but are thought to be primarily determined by *** hypothesize that the age-related decline in bone quality results from the suppression of osteocyte perilacunar/canalicular remodeling(PLR),which maintains bone material *** examined bones from young and aged mice with osteocyte-intrinsic repression of TGFβsignaling(TβRII^(ocy−/−))that suppresses *** control aged bone displayed decreased TGFβsignaling and PLR,but aging did not worsen the existing PLR suppression in male TβRII^(ocy−/−)*** relationship impacted the behavior of collagen material at the nanoscale and tissue scale in macromechanical *** effects of age on bone mass,density,and mineral material behavior were independent of osteocytic TGFβ.We determined that the decline in bone quality with age arises from the loss of osteocyte function and the loss of TGFβ-dependent maintenance of collagen integrity.

关键词： maintain primarily integrity