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Rekindling *** Cooperation

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Beijing Review 2024年第26期67卷 22-23页

作者： denis Simon The Institute for China-America Studies in Washington D.C

Chinese President Xi Jinping's recent reply to a letter from Lamont Repollet,/President of Kean University in New Jersey,the U.S.,could not have occurred at a more opportune *** against the backdrop of the 50,000-student initiative announced by President Xi during a visit to the United States in November 2023,the letter emphasized the importance of educational exchanges in building positive bilateral relations,and called on universities in both countries to strengthen cooperation in pursuing ***.

关键词： U.S. letter universities

Correcting distortions of thin-walled machined parts by machine hammer peening

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Chinese Journal of Aeronautics 2024年第6期37卷 439-453页

作者： Aitor MADARIAGA Mikel CUESTA Gorka ORTIZ-DE-ZARATE Eneko SAENZ-DE-ARGANDONA denis SORIANO Michael B.PRIME Pedro Jose ARRAZOLA Department of Materials University of ManchesterOxford RoadManchester M139PLUnited Kingdom Mechanical and Industrial Production Department Faculty of EngineeringMondragon UnibertsitateaArrasate 20500Spain Los Alamos National Laboratory Los AlamosNew MexicoUSA

Thin-walled aerostructural components frequently get distorted after the machining *** to correct distortions or eventually rejecting parts significantly increases the *** paper proposes a new approach to correct distortions in thin-walled components by strategically applying hammer peening on target surfaces of a machined *** alloy 7475-T7351 was chosen for this *** study was divided in two ***,the residual stresses(RS)induced by four different pneumatic hammer peening conditions(modifying the stepover distance and initial offset)were characterised in a test coupon,and one of the conditions was selected for the next *** the second stage,a FEM model was used to predict distortions caused by machining in a representative ***,the RS induced by hammer peening were included in an FEM model to define two hammer peening strategies(varying the coverage area)to analyse the capability to reduce *** workpieces were machined and then treated with the simulated hammer peening strategies for experimental *** in the test coupon showed that pneumatic hammer peening can generate high compressive RS(-50 to350 MPa)up to 800 lm depth,with their magnitude increasing with a reduced stepover *** of hammer peening over 4% of the surface of the representative workpiece reduced the machininginduced distortions by 37%,and a coverage area of 100% led to and overcorrection by a factor of *** confirms that hammer peening can be strategically applied(in target areas and changing the percentage of coverage)to correct low or severe distortions.

关键词： Aeronautics Machining,Hammer Peening Aluminium alloy Distortions Residual Stress

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Long-term Speckle Interferometric Monitoring of Binary Systems:2007–2023Positional Measurements and Orbits of Seven Objects

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Research in Astronomy and Astrophysics 2024年第9期 149-157页

作者： Arina Mitrofanova Vladimir Dyachenko Anatoly Beskakotov Yuri Balega Alexander Maksimov denis Rastegaev Special Astrophysical Observatory

The results of seventeen years of speckle interferometric monitoring of seven objects (Chara 122Aa,GJ 3010,HIP1987,GJ 3076,HIP 11253,HIP 11352,and HIP 14929) are *** data were obtained at the 6 m Big Telescope Alt-azimuthal Special Astrophysical Observatory of the Russian Academy of Science (BTA SAO RAS) from 2007 to the *** of previously published and new measurements made it possible to construct completely new orbits for Chara 122Aa,HIP 11253,and HIP *** orbit of GJ 3076 cannot be constructed accurately due to the large influence of the weights assigned to the *** resulting orbital solutions are classified based on a grading scheme suggested by ***,*** and ***;most orbits are“definitive”(Grade 1).The mass sums and masses of components calculated by two independent methods using Hipparcos and Gaia DR2 and DR3 parallaxes were compared for the objects under study.

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Laser-optimized Pt-Y alloy nanoparticles embedded in Pt-Y oxide matrix for high stability and ORR electrocatalytic activity

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Journal of Energy Chemistry 2024年第5期92卷 508-520页

作者： Riccardo Brandiele Andrea Guadagnini Mattia Parnigotto Federico Pini Vito Coviello denis Badocco Paolo Pastore Gian Andrea Rizzi Andrea Vittadini Daniel Forrer Vincenzo Amendola Christian Durante Department of Chemical Sciences University of PaduaVia Marzolo 135131 PadovaItaly Istituto di Chimica della Materia Condensata e di Tecnologie per l’Energia ICMATE-CNR via marzolo 1 I-35131 PadovaItaly

The development of active yet stable catalysts for oxygen reduction reaction(ORR)is still a major issue for the extensive permeation of fuel cells into everyday *** nanostructured Pt catalysts are to date the best available systems in terms of activity,the same is not true for stability,particularly under operating *** this work,Pt_(Х)Y alloy nanoparticles are proposed as active and durable electrocatalysts for ***_(Х)Y nanoalloys are synthesized and further optimized by laser ablation in liquid followed by laser fragmentation in *** novel integrated laser-assisted methodology succeeded in producing Pt_(Х)Y nanoparticles with the ideal size(markably more active with E_(1/2)=0.943 V ***,specific activity=1095μA cm^(-2) and mass activity>1000 A g^(-1).At the same time,the nanoalloys are embedded in a fine Pt oxide matrix,which allows a greater stability of the catalyst than the commercial Pt reference,as directly verified on a gas diffusion electrode.

关键词： Electrocatalysis GDE ORR Pt_(2)Y Pt_(3)Y LAL LFL Oxide support Pto Nanoalloys

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Prevalence and Factors Associated with Refractive Errors among University Students at Mbarara University of Science and Technology, Uganda

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Open Journal of Ophthalmology 2024年第3期14卷 324-338页

作者： denis Kamara John Onyango Simon Arunga Mwanja Pius Pliers denis Tusingwire mary Assumpta Ayoo Eric Ronald Mulongo Barnabas Atwiine Department of Ophthalmology Mbarara University of Science and Technology Mbarara City Uganda College of Health Sciences Makerere University Kampala Uganda London School of Hygiene and Tropical Medicine London England Faculty of Business and Development Studies Gulu University Gulu Uganda College of Health Sciences Lira University Lira Uganda

Introduction: WHO estimated that uncorrected refractive errors are the leading cause of visual impairment and second leading cause of blindness globally. University students are prone to developing refractive errors due to their curriculum that requires a lot of near work affecting their performance and quality of life unknowingly. Genetic and environmental factors are thought to play a role in the development of refractive errors. This study addresses the paucity of knowledge about refractive errors among university students in East Africa, providing a foundation for further research. Objectives: To determine the prevalence and factors associated with refractive errors among students in the Faculty of Medicine at Mbarara University of Science and Technology. Methodology: This was a cross-sectional descriptive and analytical study in which 368 undergraduate students selected using random sampling were assessed for refractive errors from march 2021-July 2021. Eligible participants were recruited and their VA assessment done after answering a questionnaire. Students whose VA improved on pin hole had subjective retinoscopy and results were compiled and imported to STATA 14 for analysis. Results: The prevalence of refractive errors was 26.36% with (95% CI) among university students especially myopia. Myopia is most predominant at 60%, followed by 37% Astigmatism and hyperopia of 3% among medical students. Astigmatism consisted of largely myopic astigmatism 72% (26) and 28% (10) compound/mixed astigmatism only. Student positive family history of refractive error was found to have a statistically significant relationship with refractive errors with AOR 1.68 (1.04 - 2.72) (95% CI) and P (0.032). Conclusion: The prevalence of refractive errors among university students, especially myopia, was found to be high and family history was associated with students having refractive errors.

关键词： Refractive Errors Prevalence Myopia Astigmatism Hyperopia Hypermetropia University Students Blindness Visual Impairment

Cu/TiO_(2) Photocatalysts for CO_(2) Reduction: Structure and Evolution of the Cocatalyst Active Form

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Transactions of Tianjin University 2024年第2期30卷 140-151页

作者： Andrey A.Saraev Anna Yu.Kurenkova denis D.Mishchenko Alexandr L.Trigub Evgeniy Yu.Gerasimov Ekaterina A.Kozlova Boreskov Institute of Catalysis Lavrentieva Ave 5Novosibirsk 630090Russia Synchrotron Radiation Facility SKIF Boreskov Institute of CatalysisNikol’skiy Ave 1Kol’tsovo 630559Russia National Research Center “Kurchatov Institute”Kurchatova Sq 1Moscow 123182Russia

Extensive work on a Cu-modified TiO_(2) photocatalyst for CO_(2) reduction under visible light irradiation was conducted. The structure of the copper cocatalyst was established using UV-vis diff use refl ectance spectroscopy, high-resolution transmis- sion electron microscopy, X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy. It was found that copper exists in different states (Cu 0 , Cu^(+) , and Cu^(2+) ), the content of which depends on the TiO_(2) calcination temperature and copper loading. The optimum composition of the cocatalyst has a photocatalyst based on TiO_(2) calcined at 700℃ and modified with 5 wt% copper, the activity of which is 22 μmol/(h·g cat ) (409 nm). Analysis of the photocatalysts after the photocatalytic reaction disclosed that the copper metal on the surface of the calcined TiO_(2) was gradually converted into Cu_(2) O during the photocatalytic reaction. Meanwhile, the metallic copper on the surface of the noncalcined TiO_(2) did not undergo any trans- formation during the reaction.

关键词： Photocatalysis Photocatalytic CO_(2)conversion Visible light Titanium dioxide Copper Copper oxides Methane formation Photocatalyst transformation

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Recent advances in the magnetic reconnection, dipolarization, and auroral processes at giant planets from the perspective of comparative planetology

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Earth and Planetary Physics 2024年第5期8卷 659-672页

作者： ZhongHua Yao RuiLong Guo Yong Wei Bertrand Bonfond denis Grodent BinZheng Zhang William R.Dunn ZuYin Pu Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences Laboratoire de Physique Atmosphérique et Planétaire STAR InstituteUniversitéde Liège Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong University Department of Earth Sciences the University of Hong Kong Department of Physics and Astronomy University College London School of Earth and Space Sciences Peking University

Magnetic reconnection and dipolarization are crucial processes driving magnetospheric dynamics, including particle energization, mass circulation, and auroral processes, among others. Recent studies have revealed that these processes at Saturn and Jupiter are fundamentally different from the ones at Earth. The reconnection and dipolarization processes are far more important than previously expected in the dayside magnetodisc of Saturn and potentially Jupiter. Dayside magnetodisc reconnection was directly identified by using Cassini measurements(Guo RL et al., 2018b) and was found to be drizzle-like and rotating in the magnetosphere of Saturn(Delamere et al., 2015b; Yao ZH et al., 2017a; Guo RL et al., 2019). Moreover, magnetic dipolarization could also exist at Saturn's dayside(Yao ZH et al., 2018), which is fundamentally different from the terrestrial situation. These new results significantly improve our understanding of giant planetary magnetospheric dynamics and provide key insights revealing the physics of planetary aurorae. Here, we briefly review these recent advances and their potential implications for future investigations.

关键词： magnetosphere magnetic reconnection magnetic depolarization

Prediction of Low Heating Value of Sugar Cane Bagasse as a Fuel for Industrial Boilers in the High Relative Humidity Region: Case of Cameroon

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Open Journal of Applied Sciences 2024年第6期14卷 1604-1624页

作者： Pierre Kana-Donfack Maxell Tientcheu-Nsiewe denis Tcheukam-Toko César Kapseu Department of Mechanical Engineering College of Technology University of Buea Buea Cameroon Department of Fundamental Sciences and Engineering Technology School of Chemical Engineering and Mineral Industries University of Ngaoudr Ngaoudr Cameroon Department of Process Engineering National School of Agro-Industrial Science University of Ngaoundr Ngaoudr Cameroon

Many attempts have been made to estimate calorific value of bagasse using mathematical equations, which were created based on data from proximate, ultimate, physical and chemical analysis. Questions have been raised on the applicability of these equations in different parts of the globe. This study was initiated to tackle these problems and also check the most suited mathematical models for the Law Heating Value of Cameroonian bagasse. Data and bagasse samples were collected at the Cameroonian sugarcane factory. The effects of cane variety, age of harvesting, source, moisture content, and sucrose on the LHV of Cameroon bagasse have been tested. It was shown that humidity does not change within a variety, but changes from the dry season to the rainy season;the sugar in the rainy season is significantly different from that collected in the dry season. Samples of the same variety have identical LHV. LHV in the dry season is significantly different from LHV in the rainy season. According to the fact that this study was done for cane with different ages of harvesting, the maturity of Cameroonian sugarcane does not affect LHV of bagasse. Tree selected models are much superior tool for the prediction of the LHV for bagasse in Cameroon compared to others. The standard deviation of these validated models is around 200 kJ/kg compared to the experimental. Thus, the models determined in foreign countries, are not necessarily applicable in predicting the LHV of bagasse in other countries with the same accuracy as that in their native country. There was linear relationship between humidity, ash and sugar content in the bagasse. It is possible to build models based on data from physical composition of bagasse using regression analysis.

关键词： Sugarcane Bagasse Relative Humidity Ash Low Heating Value

Preclinical and clinical evidence of the association of colibactinproducing Escherichia coli with anxiety and depression in colon cancer

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World Journal of Gastroenterology 2024年第21期30卷 2817-2826页

作者： Fabien Rondepierre Maëva Meynier Johan Gagniere Vincent Deneuvy Anissa Deneuvy Gwenaelle Roche Elodie Baudu Bruno Pereira Richard Bonnet Nicolas Barnich Frédéric Antonio Carvalho denis Pezet Mathilde Bonnet Isabelle Jalenques Service de Psychiatrie de l’Adulte A et Psychologie Médicale CHU Clermont-FerrandClermont-Ferrand 63000France M2iSH UMR 1071INSERMUniversity of Clermont AuvergneINRAE USC 1382Clermont-Ferrand 63001France NeuroDol UMR 1107INSERMUniversity of Clermont AuvergneClermont-Ferrand 63001France Department of Digestive Surgery CHU de Clermont-FerrandClermont-Ferrand 63001France Biostatistics Unit Department of Clinical Research and InnovationCHU Clermont-FerrandClermont-Ferrand 63000France Department of Bacteriology CHU de Clermont-FerrandClermont-Ferrand 63001France UniversitéClermont Auvergne INPCNRSClermont Auvergne Institut PascalClermont-Ferrand 63000France

BACKGROUND The association between the intestinal microbiota and psychiatric disorders is becoming increasingly *** gut microbiota contributes to colorectal carcinogenesis(CRC),as demonstrated with colibactin-producing Escherichia coli(CoPEC).AIM To evaluate the association between CoPEC prevalence and anxiety-and depressive-like behaviors with both preclinical and clinical *** Patients followed after a CRC surgery and for whom the prevalence of CoPEC has been investigated underwent a psychiatric *** were compared according to the CoPEC *** parallel C57BL6/J wild type mice and mice with a CRC susceptibility were chronically infected with a CoPEC *** behavior was assessed using the Elevated Plus Maze test,the Forced Swimming Test and the Behavior recognition system PhenoTyper®.RESULTS In a limited cohort,all patients with CoPEC colonization presented with psychiatric disorders several years before cancer diagnosis,whereas only one patient(17%)without CoPEC *** result was confirmed in C57BL6/J wildtype mice and in a CRC susceptibility mouse model(adenomatous polyposis colimultiple intestinal neoplasia/+).Mice exhibited a significant increase in anxiety-and depressive-like behaviors after chronic infection with a CoPEC *** This finding provides the first evidence that CoPEC infection can induce microbiota-gut-brain axis disturbances in addition to its procarcinogenic properties.

关键词： Colorectal cancer Colibactin Escherichia coli Colibactin-producing Escherichia coli Inflammation Anxiety Depression Behavior