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Carbon Energy 2024年第7期6卷 150-162页

作者： Yufeng Wu Minwei Song Ziyi Zhao Guang-Hui Wang Changlong Wang Didier Astruc Institute of Circular Economy Faculty of Materials and ManufacturingBeijing University of TechnologyBeijingChina Key Laboratory of Biofuels Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoChina ISM UMR CNRS N°5255Universitéde BordeauxTalence CedexFrance

The rational design of efficient bimetallic nanoparticle(NP)catalysts is challenging due to the lack of theoretical understanding of active components and insights into the mechanisms of a specific ***,we report the rational design of nanoreactors comprising hollow carbon sphere-confined PtNi bimetallic NPs(PtNi@HCS)as highly efficient catalysts for hydrogen generation via ammonia borane hydrolysis in *** both density functional theory calculations and molecular dynamics simulations,the effects of an active PtNi combination and the critical synergistic role of a hollow carbon shell on the molecule diffusion adsorption behaviors are *** isotope effects and theoretical calculations allow the clarification of the mechanism,with oxidative addition of an O-H bond of water to the catalyst surface being the rate-determining *** remarkable catalytic activity of the PtNi@HCS nanoreactor was also utilized for successful tandem catalytic hydrogenation reactions,using in situ-generated H_(2) from ammonia borane with high *** concerted design,theoretical calculations,and experimental work presented here shed light on the rational elaboration of efficient nanocatalysts and contribute to the establishment of a circular carbon economy using green hydrogen.

关键词： ammonia borane hydrogen nanoalloy nanoreactor solid catalyst

Distribution, Mobility, and Health Risks Assessment of Trace Metals in River Sediments from Intense Agricultural Activity Areas in West Africa

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Journal of Materials Science and Chemical Engineering 2024年第8期12卷 12-42页

作者： Ahbeauriet Ahmed Ouattara Maley-Pacôme Soro Albert Brou Kouadio Horo Koné Albert Trokourey Dpartment des Sciences et Technique Universit Alassane Ouattara Bouak Cte dIvoire Laboratoire de Thermodynamique et de Physico-Chimie du Milieu Universit Nangui Abrogoua Abidjan Cte dIvoire Laboratoire de Chimie Physique Universit Flix Houphout Boigny Abidjan Cte dIvoire

The economy of West African countries is mainly based on agriculture. However, the trace metal(loid)s contamination status in rivers is relatively unknown in the region. In this work, 45 surface sediments collected from the Bandama, Comoé, and Bia Rivers in south and south eastern Côte d’Ivoire (West Africa), were analyzed for total metal concentrations and chemical speciation. The results showed that the river sediments were considerably contaminated by Cd and moderately contaminated by As, Cu, Pb, and Zn. Significant spatial variations were observed among the stations but not between the rivers. Metals Cd and Cu were likely to cause more ecological risks. The speciation analysis unravelled that the metal(loid)s partitioned mainly in the residual fraction, with the potential mobile fraction varying from 14% to 28%. The study calls for establishment of strict policies relative to the application of fertilizers and agrochemicals and mining activities to protect the environment and human health risks.

关键词： River Sediment Trace Metal (Loid)s Multivariate Analysis Potential Ecological Risk Assessments Sequential Extraction Geochemical Indices

A simulation study on spatial and time resolution for a cost-effective positron emission particle tracking system

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Particuology 2024年第5期88卷 312-322页

作者： Josephine Oppotsch Matthias Steinke Miriam Fritsch Fritz-Herbert Heinsius Thomas Held Nikoline Hilse Viktor Scherer Ulrich Wiedner Ruhr-universität Bochum Institut für Experimentalphysik I44801 BochumGermany Ruhr-universität Bochum Lehrstuhl für Energieanlagen und Energieprozesstechnik44801 BochumGermany

This work is the second part of a simulation study investigating the processing of densely packed and moving granular assemblies by positron emission particle tracking (PEPT).Since medical positron emission tomography (PET) scanners commonly used for PEPT are very expensive,a PET-like detector system based on cost-effective organic plastic scintillator bars is being developed and tested for its *** this context,the spatial resolution of a resting positron source,a source moving on a freely designed model path,and a particle motion given by a discrete element method (deM) simulation is studied using Monte Carlo simulations and the software toolkit *** not only extended the simulation and reconstruction to a moving source but also significantly improved the spatial resolution compared to previous work by adding oversampling and iteration to the reconstruction ***,in the case of a source following a trajectory developed from deM simulations,a very good resolution of about 1 mm in all three directions and an average 3D deviation between simulated and reconstructed events of 2.3 mm could be ***,the resolution for realistic particle motion within the generic grate system (which is the test rig for further experimental studies) is well below the smallest particle *** simulation of the dependence of the reconstruction accuracy on tracer particle location revealed a nearly constant efficiency within the entire detector system,which demonstrates that boundary effects can be neglected.

关键词： Positron emission particle tracking Monte Carlo method Time-of-flight Plastic scintillators Silicon photomultipliers(SiPMs)

Neuroprotective effects of G9a inhibition through modulation of peroxisome-proliferator activator receptor gamma-dependent pathways by miR-128

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Neural Regeneration Research 2024年第11期19卷 2532-2542页

作者： Aina Bellver-Sanchis Pedro AAvila-López Iva Tic David Valle-García Marta Ribalta-Vilella Luis Labrador deb Ranjan Banerjee Ana Guerrero Gemma Casadesus Coralie Poulard Mercè Pallàs Christian Grinán-Ferré department of Pharmacology and Therapeutic Chemistry Institut de Neurociències-Universitat de BarcelonaBarcelonaSpain department of Biochemistry and Molecular Genetics Feinberg School of MedicineNorthwestern UniversityChicagoILUSA Institute of Biotechnology National Autonomous University of MexicoCuernavacaMexico department of Pharmacology and Therapeutics Health Science Center-University of FloridaGainesvilleFLUSA department of Chemistry National Institute of Technology DurgapurM G AvenueDurgapurWest BengalIndia Cancer Research Cancer Lyon Universitéde LyonLyonFrance Inserm U1052 Centre de Recherche en Cancérologie de LyonLyonFrance CNRS UMR5286 Centre de Recherche en Cancérlogie de LyonLyonFrance Centro de Investigación en Red Enfermedades Neurodegenerativas(CIBERNED)Instituto de Salud Carlos IIIMadridSpain Neuroimmunology department National Institute of Neurology and Neurosurgery“Manuel Velasco Suárez”Mexico CityMexico

Dysregulation of G9a,a histone-lysine N-methyltransferase,has been observed in Alzheimer’s disease and has been correlated with increased levels of chronic inflammation and oxidative ***,microRNAs are involved in many biological processes and diseases playing a key role in pathogenesis,especially in multifactorial diseases such as Alzheimer’s ***,our aim has been to provide partial insights into the interconnection between G9a,microRNAs,oxidative stress,and *** better understand the biology of G9a,we compared the global microRNA expression between senescence-accelerated mouse-prone 8(SAMP8)control mice and SAMP8 treated with G9a inhibitor *** found a downregulation of miR-128 after a G9a inhibition treatment,which interestingly binds to the 3′untranslated region(3′-UTR)of peroxisome-proliferator activator receptor γ(PPARG)***,Pparg gene expression levels were higher in the SAMP8 group treated with G9a inhibitor than in the SAMP8 control *** also observed modulation of oxidative stress responses might be mainly driven Pparg after G9a *** confirm these antioxidant effects,we treated primary neuron cell cultures with hydrogen peroxide as an oxidative *** this setting,treatment with G9a inhibitor increases both cell survival and antioxidant ***,up-regulation of PPARγby G9a inhibitor could also increase the expression of genes involved in DNA damage responses and *** addition,we also described that the PPARγ/AMPK axis partially explains the regulation of autophagy markers ***,PPARγ/GADD45αpotentially contributes to enhancing synaptic plasticity and neurogenesis after G9a ***,we propose that pharmacological inhibition of G9a leads to a neuroprotective effect that could be due,at least in part,by the modulation of PPARγ-dependent pathways by miR-128.

关键词： aging cognitive decline epigenetics G9a inhibition microRNAs miR-128 peroxisome-proliferator activator receptorγ(PPARγ) PPARG SAMP8

A simulation study for a cost-effective PET-like detector system intended to track particles in granular assemblies

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Particuology 2024年第1期84卷 117-125页

作者： Josephine Oppotsch Antonios Athanassiadis Miriam Fritsch Fritz-Herbert Heinsius Thomas Held Nikoline Hilse Viktor Scherer Matthias Steinke Ulrich Wiedner Ruhr-universität Bochum Institut für Experimentalphysik I44801 BochumGermany Ruhr-universität Bochum Lehrstuhl für Energieanlagen und Energieprozesstechnik44801 BochumGermany

Since many industrial applications rely on the processing of densely packed and moving granular ma-terial,obtaining bulk internal information on the particle movement inside the reactors is of great *** information can be delivered by Positron Emission Particle Tracking(PEPT).By marking pellets with a positron-emitting radioisotope,the position of these tracer particles can be determined via the time-of-flight differences of the emitted gamma-ray *** current paper proposes a PET-like detector system based on cost-effective organic plastic scintillators instead of the more common but expensive inorganic *** system is currently under construction and was tested for its resolution and efficiency in this simulation *** Monte Carlo simulations and the software toolkit Geant4,three different geometries(an empty glass box,a generic grate system,and a cubic box of 1 m3 completely filled with pellets)were investigated,leading to a spatial resolution in the millimeter range and an efficiency,defined as the ratio of reconstructed decay locations to simulated decays,of 2.7%,1.4%,and 0.3%.

关键词： Positron emission particle tracking Geant4 Monte Carlo method Time-of-flight Plastic scintillators Silicon photomultipliers(SiPMs)

Physico-Chemical Characterization of Some Honeys from the Savannah-Gallery Forest Complex and Primary Forest in Gabon

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Open Journal of Applied Sciences 2024年第7期14卷 1904-1917页

作者： Charline Obone Madi Guirema Abaker Silas Davy Mbadinga Boubala Estelle Dumont Gino Boussiengui-Boussiengui Alexis Nicaise Lepengue Dpartement Sciences Fondamental de lIngnieur Institut National Suprieur dAgronomie et de Biotechnologies Universit des Sciences et Techniques de Masuku Franceville Gabon Dpartement de Biochimie Facult des Sciences Universit des Sciences et Techniques de Masuku Franceville Gabon LAboratoire de Recherche Multidisciplinaire en Environnement (LARME) USTM Franceville Gabon Dpartement de Phytotechnologie Institut National Suprieur dAgronomie et de Biotechnologies Universit des Sciences et Techniques de Masuku Franceville Gabon

Honey harvesting throughout beekeeping is a technology recently introduced in Gabon comparing to the other African countries well known in international honey trade. The purpose of this study is to contribute to the knowledge of the quality of multi-flower honeys from the savannah-gallery forest complex and primary forest not well documented in Gabon. Physical and chemical parameters of different honeys were analyzed using the official methods of analysis of the Association of Official Analytical Chemists. The results of physico-chemical analysis show variations in pH (3.4 to 3.9), free acidity (37.12 to 76.65 meq∙kg−1), water content (17.49% to 21.21%), electrical conductivity (0.64 to 1.24 mS∙cm−1), density (1.02 to 1.03) and total sugar content (77% to 82%). These variations were significantly different (p dependent of the type of ecosystem considered. The pH values confirmed the botanical origin of the five honeys. The physico-chemical parameters of the honeys show significant correlations (p density (r = −0.552) and total sugar content (r = −0.890). Conductivity is positively correlated with free acidity (r = 0.688) and total sugar content (r = 0.776), and negatively correlated with water content (r = −0.628). All honeys were in line with Codex Alimentarius standards, except for 3 types of honey (M1, M2 and M4) for free acidity and electrical conductivity, showing possible fermentation of these honeys.

关键词： Physico-Chemical Parameters Honey Gabon Codex Alimentarius

Epidemiologic, Diagnostic, and Therapeutic Features of Urinary Stone Disease in Northern Benin from 2018 to 2023

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Open Journal of Urology 2024年第2期14卷 128-137页

作者： Gandaho Isidore Sossa Jean Toré Sanni Rafiou Dènon Emmanuel Allodé Alexandre Avakoudjo Déjinnin Josué Georges Département de Chirurgie et Spécialités Chirurgicales Université de Parakou Parakou Bénin Faculté des Sciences de la Santé Université d’Abomey-Calavi Abomey-Calavi Bénin

Objective: To determine the epidemiologic, diagnostic, and therapeutic features of urinary in northern Benin from 2018 to 2023. Patients and Method: The study was an observational and descriptive one. We exhaustively and retrospectively collected data from the medical records of the patients that were managed from February 1, 2018 to February 1, 2023 at the department of Surgery of “Centre Hospitalier universitaire Départmental Borgou-Alibori or CHUD-BA”. Results: Among the 4522 patients managed, 75% or 1.7% had urinary stone disease. Their mean age was 41 years. The sex ratio was 2.75, the males being predominantly affected. Of the 75 cases of urinary stone disease, 30.7% (n = 23) were renal, 46.7% (n = 35) were ureteral, and 22.7% (n = 17) were vesical. The patients came from variable geographical areas, ethnic groups, and professional sectors. Their main complaints were pain (57.3%), hematuria (14.7%), dysuria (12%), and fever (5.3%). 15 (20%) patients, i.e., 7 renal stone and 8 ureteral stone patients, had an obstructive renal failure. The imaging tools available were ultrasonography, tomography and computed tomographic scan. 11 of the bladder stone cases (64.7%) were associated with a bladder outlet obstruction. Overall, 38.7% of the patients had either diabetes mellitus (6.7%), hypertension or high blood pressure (6.7%), benign prostate hyperplasia (8%), urinary schistosomiasis (6.7%), ureteral pelvic junction obstruction (2.7%), and prostate cancer (1.3%). Of the 19 patients whose dietary behavior was investigated 15 (79%), 11 (57.9%) et 11 (57.9%) demonstrated a diet which was respectively rich in milk, fromage and meat. 100% of bladder stones were removed through cystolithotomy. Renal stones were removed by pyelolithtomy (52.2%) and nephrolithotomy (21.7%). Ureteral stones were removed through ureterolithotomy (40%), expelled by means of alpha-blockers (40%) or managed with ureteral pigtail stent (20%). Conclusion: The hospital prevalence of urinary stone d

关键词： Urinary Stone Epidemiologic Diagnostic Therapeutic

Effects of Conjugated Systems on UV-Visible Light-sensitive D-π-A Type Sulfonium Salt Photoacid Generators

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Chinese Journal of Polymer Science 2016年第12期34卷 1456-1468页

作者： Xing-yu Wu 金明 Jian-chao Xie de-cheng Wan Jean Pierre Malval School of Materials Science and Engineering Tongji UniversityShanghai 201804China Institut de Science des Mattériaux de Mulhouse UMR CNRS 7361Universitéde Haute-Alsace15 rue Jean Starcky68057 MulhouseFrance

A series of D-π-A type sulfonium salt photoacid generators with different π-conjugated structures, such as triphenyl, phenylstilbene, styryl-biphenyl, and stilbene, were designed to determine the effect of molecular structures on the photochemical and photophysical properties. The mechanisms of photochemical generation of H＋ were studied by UV-Vis spectroscopy, theoretical calculations, and fluorescence spectroscopy. It is found that the frontier orbits determine the absorption, the molar extinction coefficients, and the quantum yields of photoacid generation. Triphenyl systems connected with sulfonium are beneficial to increase the quantum yields of acid generation. The photoreactivity of four sulfonium salts was further evaluated through the polymerizations of various epoxide monomers at different irradiation wavelengths （365- 425 nm） by using the real-time infrared spectroscopy with light-emitting diodes. The high quantum yields for acid generation （ФH＋ = -0.32 to 0.58） and the high molar extinction coefficients （ε = -23500 ***-1 to 31000 ***-1） of the sulfonium salts lead to high conversion rates （over 50%-80%）. Hence, these photoinitiators exhibit potential for the photocuring applications.

关键词： Sulfonium salt Photoacid generators π-conjugated structures.

Tensile strength and failure behavior of rock-mortar interfaces: Direct and indirect measurements

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 41-55页

作者： Ghasem Shams Patrice Rivard Omid Moradian Civil Engineering and Building Engineering department Universitéde SherbrookeSherbrookeQuébecCanada department of Earth Sciences Swiss Federal Institute of Technology(ETH)ZurichSwitzerland department of Civil and Environmental Engineering Colorado School of MinesGoldenCOUSA

The tensile strength at the rock-concrete interface is one of the crucial factors controlling the failure mechanisms of structures,such as concrete gravity *** the critical importance of the failure mechanism and tensile strength of rock-concrete interfaces,understanding of these factors remains very *** study investigated the tensile strength and fracturing processes at rock-mortar interfaces subjected to direct and indirect tensile *** image correlation(DIC)and acoustic emission(AE)techniques were used to monitor the failure mechanisms of specimens subjected to direct tension and indirect loading(Brazilian tests).The results indicated that the direct tensile strength of the rock-mortar specimens was lower than their indirect tensile strength,with a direct/indirect tensile strength ratio of 65%.DIC strain field data and moment tensor inversions(MTI)of AE events indicated that a significant number of shear microcracks occurred in the specimens subjected to the Brazilian *** presence of these shear microcracks,which require more energy to break,resulted in a higher tensile strength during the Brazilian *** contrast,microcracks were predominantly tensile in specimens subjected to direct tension,leading to a lower tensile *** monitoring of the cracking processes in the rock-mortar interfaces revealed that they show AE precursors before failure under the Brazilian test,whereas they show a minimal number of AE events before failure under direct *** to different microcracking mechanisms,specimens tested under Brazilian tests showed lower roughness with flatter fracture surfaces than those tested under direct tension with jagged and rough fracture *** results of this study shed light on better understanding the micromechanics of damage in the rock-concrete interfaces for a safer design of engineering structures.

关键词： Rock-mortar Rock-concrete Moment tensor inversion(MTI) Acoustic emission(AE) Digital image correlation(DIC) Tensile strength Direct tensile test Brazilian test

AN OPTIMAL CONTROL PROBLEM FOR A LOTKA-VOLTERRA COMPETITION MOdeL WITH CHEMO-REPULSION

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Acta Mathematica Scientia 2024年第2期44卷 721-751页

作者： Diana I.HERNÁNdeZ Diego A.RUEDA-GOMEZ Élder J.VILLAMIZAR-ROA Universidad Industrial de Santander Escuela de MatemáticasA.A.678BucaramangaColombia

In this paper we study a bilinear optimal control problem for a diffusive Lotka-Volterra competition model with chemo-repulsion in a bounded domain of ℝ^(ℕ),N=2,*** model describes the competition of two species in which one of them avoid encounters with rivals through a chemo-repulsion *** prove the existence and uniqueness of weak-strong solutions,and then we analyze the existence of a global optimal solution for a related bilinear optimal control problem,where the control is acting on the chemical ***,we derive first-order optimality conditions for local optimal solutions using the Lagrange multipliers ***,we propose a discrete approximation scheme of the optimality system based on the gradient method,which is validated with some computational experiments.

关键词： Lotka-Volterra chemo-repulsion optimal control optimality conditions