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Three Problems on Trigonometric Sums

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Acta Mathematica Sinica,English Series 2019年第6期35卷 721-727页

作者： yves meyer CMLA ENS Paris-Saclay

Let Λ ? R^n be a uniformly discrete set and let C_Λ be the vector space consisting of all mean periodic functions whose spectrum is simple and contained in Λ. If Λ is a gentle set then for every f ∈ C_Λ we have f(x) = O(ω_Λ(x)) as |x| →∞ and ω_Λ(x) can be estimated(Theorem 4.1). This line of research was proposed by Jean-Pierre Kahane in 1957.

关键词： Mean periodic functions almost periodic functions trigonometric sums

Accumulation of Flavonoids in an ntra ntrb Mutant Leads to Tolerance to UV-C

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Molecular Plant 2009年第2期2卷 249-258页

作者： Talaat Bashandy Ludivine Taconnat Jean-Pierre Renou yves meyer Jean-Philippe Reichheld Laboratoire Genome et Developpement des Plantes Universite de Perpignan UMR CNRS 5096 52 avenue Paul Alduy 66860 Perpignan France Unite de Recherche en Genomique Vegetale 91057 Evry cedex France

NADPH-dependent thioredoxin reductases （NTRs） are key regulatory enzymes determining the redox state of thioredoxins. There are two genes encoding NTRs （NTRA and NTRB） in the Arabidopsis genome, each encoding a cytosolic and a mitochondrial isoform. A double ntra ntrb mutant has recently been characterized and shows slower plant growth, slightly wrinkled seeds and a remarkable hypersensitivity to buthionine sulfoximine （BSO）, a specific inhibitor of gluta- thione biosynthesis. In this paper, we demonstrate that this mutant also accumulates higher level of flavonoids. Analysis of transcriptome data showed that several genes of the flavonoid pathway are overexpressed in the ntra ntrb mutant. Accumulation of flavonoids is generally considered a hallmark of plant stress. Nevertheless, no elevation of the expression of genes encoding ROS-detoxification enzymes was observed, suggesting that the ntra ntrb plants do not suffer from oxidative disease. Another hypothesis suggests that flavonoids are specifically synthesized in the ntra ntrb mutant in order to rescue the inactivation of NTR. To test this, the ntra ntrb mutant was crossed with transparent testa 4 （tt4） plants with a mutation in the gene encoding the first enzyme in flavonoid biosynthesis. As ntra ntrb plants are more resistant to UV-C treatment than wild-type plants, this higher resistance was abolished in the ntra ntrb tt4 mutant, suggesting that accumulation of flavonoids in the ntra ntrb mutant protects plants against UV-light.

关键词： abiotic/environmental stress oxidative and photo-oxidative stress secondary metabolism - phenylpropanoidsand phenolics gene expression Arabidopsis.

Multifunctional properties of a polar spin chain compound[N(C_(3)H_(7))_(4)][Cu(C_(8)H_(4)NO_(4))]·H_(2)O exhibiting both one-dimensional magnetism and nonlinear optical activity

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Chinese Chemical Letters 2024年第2期35卷 622-625页

作者： Ang Li Yanhong Wang Haotian Tian Alimujiang Yalikun yves Journaux Min Luo Hongcheng Lu Key Laboratory of Material Chemistry for Energy Conversion and Storage School of Chemistry and Chemical EngineeringHubei Key Laboratory of Bioinorganic Chemistry & Materia MedicaHuazhong University of Science and TechnologyWuhan 430074China Key Laboratory of optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 35002China Institut Parisien de Chimie Moléculaire IPCMSorbonne UniversitéCNRSParis F-75252France

Functional materials with multiple properties are urgent to be explored to reach high requirements for applications nowadays.In this work,a new multifunctional one-dimensional(1D)chain compound[N(C_(3)H_(7))_(4)][Cu(ohpma)]·H_(2)O 1(ohpma=deprotonated N-(2-hydoxyphenyl)oxamic acid)exhibiting both 1D antiferromagnetic and nonlinear optical properties,which are both originated from the same polar[Cu(C_(8)H_(4)NO_(4))]magnetic units,has been successfully synthesized by evaporation at room temperature.Bis-polydentate nature of the(ohpma)3−ligand with constrained tridentate and bidentate coordination sites conducts Cu^(2+)ions coordinating in different geometries and forms 1D chains along the c axis,which are further separated by the[N(C_(3)H_(7))_(4)]+cations.And the 1D magnetic chains further exhibit noncentrosymmetric polar arrangement.Nonlinear optical study shows polar compound 1 exhibits a discernible second-harmonic generation(SHG)efficiency and the calculation of the partial density of states indicates that the SHG efficiency of 1 is mainly originated from the polar[Cu(C_(8)H_(4)NO_(4))]magnetic units.Moreover,magnetic susceptibility shows a broad maximum around 70 K with strong intrachain interaction of J/k B=−113.0 K but no long-range order is observed down to 2 K,suggesting that 1 shows a good 1D magnetism.Both good 1D magnetism and SHG activity suggest that 1 could be as a potential multifunctional material,particularly.

关键词： Multifunctional properties Magnetic property Nonlinear optical property Evaporation One-dimensional chain

France-China‘Brotherhood'in My Eyes

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China News Release 2024年第2期 14-17页

作者： yves Mouillet tbe French Chaunel of CGTN China Media Group

Though thousands of miles apart,the ancient and refined civilization of China has always held a profound fascination for the people of France.Looking back at the history of recent several centuries,from historical texts and landmarks to meetings between heads of state,we can see many precious moments of amicable exchanges between the two countries.

关键词： refined exchanges profound

Associations between physical activity levels and ATPase inhibitory factor 1 concentrations in older adults

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Journal of Sport and Health Science 2024年第3期13卷 409-418页

作者： Jérémy Raffin yves Rolland Annelise Genoux Guillaume Combes Mikael Croyal Bertrand Perret Sophie Guyonnet Bruno Vellas Laurent O.Martinez Philipe de Souto Barreto For the MAPT/DSA Group Institut du Vieillissement Gérontopôle de ToulouseCentre Hospitalo-Universitaire de ToulouseToulouse 31000France Centre d'Epidémiologie et de Recherche en Santédes Populations UnitéMixte de Recherche 1295Institut National de la Santéet de la Recherche MédicaleUniversitéToulouse-III-Paul-SabatierToulouse 31000France LimitAging Team Institut des Maladies Métaboliques et CardiovasculairesUnitéMixte de Recherche 1297Institut National de la Santéet de la Recherche MédicaleUniversitéToulouse III-Paul SabatierToulouse 31432France Service de Biochimie Pôle de biologieHôpital de PurpanCentre Hospitalo-Universitaire de ToulouseToulouse 31300France L'Institut du Thorax Institut National de la Santéet de la Recherche MédicaleCentre National de la Recherche ScientifiqueCentre Hospitalo-Universitaire de NantesNantes UniversitéNantes 44000France BioCore US16Structure Fédérative de Recherche BonamyInstitut National de la Santéet de la Recherche MédicaleCentre National de la Recherche ScientifiqueCentre Hospitalo-Universitaire de NantesNantes UniversitéNantes 44000France Plate-forme de spectrométrie de masse Centre de Recherche en Nutrition HumaineOuestNantes 44000France 不详

Background:Adenosine triphosphatase inhibitory factor 1(IF1)is a key protein involved in energy metabolism.IF1 has been linked to various agerelated diseases,although its relationship with physical activity(PA)remains unclear.Additionally,the apolipoprotein A-I(apoA-I),a PA-modulated lipoprotein,could play a role in this relationship because it shares a binding site with IF1 on the cell-surface ATP synthase.We examined here the associations between chronic PA and plasma IF1 concentrations among older adults,and we investigated whether apoA-I mediated these associations.Methods:In the present work,1096 healthy adults(63.8%females)aged 70 years and over who were involved in the Multidomain Alzheimer Prevention Trial study were included.IF1 plasma concentrations(square root of ng/mL)were measured at the 1-year visit of the Multidomain Alzheimer Prevention Trial,while PA levels(square root of metabolic equivalent task min/week)were assessed using questionnaires administered each year from baseline to the 3-year visit.Multiple linear regressions were performed to investigate the associations between the first-year mean PA levels and IF1 concentrations.Mediation analyses were conducted to examine whether apoA-I mediated these associations.Mixedeffect linear regressions were carried out to investigate whether the 1-year visit IF1 concentrations predicted subsequent changes in PA.Results:Multiple linear regressions indicated that first-year mean PA levels were positively associated with IF1 concentrations(B=0.021;SE=0.010;p=0.043).Mediation analyses revealed that about 37.7%of this relationship was mediated by apoA-I(B_(ab)=0.008;SE=0.004;p=0.023).Longitudinal investigations demonstrated that higher concentrations of IF1 at the 1-year visit predicted a faster decline in PA levels over the subsequent 2 years(time×IF1:B=0.148;SE=0.066;p=0.025).Conclusion:This study demonstrates that regular PA is associated with plasma IF1 concentrations,and it suggests that apoA-I partly mediates this association.Additionally,this study f

关键词： Aging Apolipoprotein Bioenergetics Exerkine Mitochondria

Numerical Assessment of the Thermal Efficiency of a Concentrated Photovoltaic/Thermal (CPV/T) Hybrid System Using Air as Heat Transfer Fluid

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Smart Grid and Renewable Energy 2024年第1期15卷 1-14页

作者： Amadou Konfe Boureima Kabore yves Christian Nonguierma Fatimata Ouedraogo Sié Kam Laboratory of Thermal and Renewable Energies University Joseph Ki-Zerbo Ouagadougou Burkina Faso Physic Department University Norbert Zongo Koudougou Burkina Faso Photonics and Nolinear Optics Laboratory University of Moncton Moncton Canada

In this paper, we propose a thermal model of a hybrid photovoltaic/thermal concentration system. Starting from the thermal balance of the model, the equation is solved and simulated with a MATLAB code, considering air as the cooling fluid. This enabled us to evaluate some of the parameters influencing the electrical and thermal performance of this device. The results showed that the temperature, thermal efficiency and electrical efficiency delivered depend on the air mass flow rate. The electrical and thermal efficiencies for different values of air mass flow are encouraging, and demonstrate the benefits of cooling photovoltaic cells. The results show that thermal efficiency decreases air flow rate greater than 0.7 kg/s, whatever the value of the light concentration used. The thermal efficiency of the solar cell increases as the light concentration increases, whatever the air flow rate used. For a concentration equal to 30 sun, the thermal efficiency is 0.16 with an air flow rate equal to 0.005 kg/s;the thermal efficiency increases to 0.19 with an air flow rate equal to 0.1 kg/s at the same concentration. An interesting and useful finding was that the proposed numerical model allows the determination of the electrical as well as thermal efficiency of the hybrid CPV/T with air flow as cooling fluid.

关键词： PV Cell Concentrating Thermal Energy Conversion Cooling Hybrid System

Fatty Acid Composition of Hazelnut Kernel Oil from Coula edulis Collected in the Republic of Congo

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Food and Nutrition Sciences 2024年第4期15卷 290-297页

作者： Josiane Enzonga Yoca Jean Paul Latran Ossoko yves Okandza Michel Didace Mvoula Tsieri Laboratoire de Contrô le et Qualit&#233 des Aliments de l&#8217Ecole Nationale Sup&#233rieure d&#8217Agronomie et de Foresterie Universit&#233 Marien NGOUABI Brazzaville Congo Université Denis Sassou NGUESSO Brazzaville Congo

Coula edulis is non-timber forest product (NTFP) used in Africa for its hazelnuts, which contain edible seeds with a demonstrated nutritional potential. However, there have been very few scientific studies of this species in the Republic of Congo. Thus, the aim of the current study was therefore to determine the fatty acid composition of the oil extracted from Coula edulis hazelnut seeds collected at random in the Republic of Congo. The oil was extracted using the Soxhlet method and its fatty acid composition was determined by gas chromatography. The extracted oil from Coula edulis hazelnut kernels is rich in monounsaturated fatty acids (95.28%), particularly oleic acid (94.5%), which classifies it as an oleic oil and gives it interesting nutritional and therapeutic properties. On the other hand, saturated fatty acids (4.15%) and polyunsaturated fatty acids (0.35%) are not well represented. Its low poly-unsaturated fatty acid content makes it more stable when stored at room temperature.

关键词： Coula edulis Fatty Acids Oil Seeds Hazelnuts Republic of Congo NTFP

Incidence and Management of Occupational Blood Exposure (OBE) among Medical Students at the University of Bangui

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Occupational Diseases and Environmental Medicine 2024年第2期12卷 68-77页

作者： Hermione Dahlia Mossoro-Kpinde Caleb Koyambenguia yves Kpangba Mangbé Saint Calvaire Henri Diemer Ministè re du Travail de l&#8217Emploi de la Protection Sociale et de la Formation Professionnelle Bangui Central African Republic Dé partement de Sant&#233 Publique &#224 la Facult&#233 des Sciences de la Sant&#233 de l&#8217Universit&#233 de Bangui Bangui Central African Republic Centre Hospitalier Universitaire de l’ Amiti&#233 Sino-Centrafricaine de Bangui Bangui Central African Republic Département de Formation Continue à la Faculté des Sciences de la Santé de l’Université de Bangui Bangui Central African Republic

Introduction: Like healthcare workers, medical students are also exposed to a risk of accidental contamination during their hospital internships. However, they do not benefit from prevention services in the same way as workers in this sector, although they actively participate in the routine care provided to patients in the various hospital departments. The objective of our study is to determine the incidence of these accidents and their medical and administrative management among these victims (medical students) not classified in the category of workers. Materials and Method: This was a cross-sectional study carried out over three months from January 15 to March 14, 2023. The study population consisted of all medical students at the Faculty of Health Sciences at the University of Bangui. Regularly enrolled students from 2nd to 7th year, on placement in hospitals in the Central African Republic and who gave their informed consent were included. Data were collected through a self-administered questionnaire. Results: A cross-sectional study was carried out among medical students concerning the incidence and management of accidents involving exposure to blood in the Central African Republic. Of the 254 students included, three (9%) had already been correctly vaccinated against the viral hepatitis B virus, 198 (77.9%) reported still having access to personal protective equipment, 133 students (52.4%) reported being victims of OBE in the past 12 months. The main types of OBE were stings (62%), followed by liquid splashes (32%) and cuts (6%). Among the 133 victims, 92.9% carried out immediate hand disinfection or abundant eye washing, 41.9% obtained the serology of the source patient and 37% reported the accident to their supervisor. Conclusion: It is important that students benefit from better prevention and management of these accidents.

关键词： Incidence of Blood Exposure Accidents Medical Student Treatment Bangui

Microbiological Quality of “Rabilé”, a Yeast Used for Fermentation of Dolo, a Local Beer in Dédougou, Burkina Faso

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Open Journal of Applied Sciences 2024年第4期14卷 849-864页

作者： Amana Metuor Dabiré Nicolas Ouédraogo Cheick Alassane Djibila Damis yves Patrik Bouniounou Molecular Biology and Genetics Laboratory (LABIOGENE) Universit&#233 Joseph Ki-Zerbo Ouagadougou Burkina Faso Training and Research Unit in Applied Sciences and Technologies Department of Biochemistry Microbiology University of Dedougou Dedougou Burkina Faso National Center for Research and Training on Malaria (CNRFP) Ouagadougou Burkina Faso

Sorghum beer or dolo is part of the eating habits of part of the population of Dédougou because of its low price compared with industrial beers. Its production is an ancestral tradition that uses traditional equipment and gives dolo organoleptic properties that are not found in industrial beers. The production process involves several stages, including fermentation, which itself comprises natural lactic fermentation followed by alcoholic fermentation using traditional yeasts, which are not controlled in any way. The general aim of this study is to assess the microbiological quality of these fermentative yeasts in the town of Dédougou, in order to contribute to the health safety of the population and the promotion of these local beers. Twenty samples of fermenting yeast were analyzed according to ISO standards, to isolate enterobacteria, total and faecal coliforms according to standard procedures for isolating these micro-organisms. The isolated strains were identified using the API20E gallery. Microbiological analyses revealed the presence of 51.17% enterobacteria, 45.38% total coliforms and 3.45% thermotolerant coliforms. We counted 40% Escherichia coli, 20% Enterobacter cloacae, 20% Klebsiella pneumoniae and 20% Klebsiella spp. All the strains detected are capable of surviving in hostile conditions and could harm the quality of the dolo, consumer health and cause real collective food poisoning in the town of Dédougou. This enabled us to assess the microbial quality of these yeasts and to propose more suitable measures for producing and preserving dolo under hygienic conditions to protect consumer health.

关键词： Dolo Yeast Rabilé Microbiological Quality Bacteria