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Maternal Mortality Risk Factors in Regional Hospital of Burkina Faso

Open Journal of epidemiology 2014年第2期4卷 57-62页

作者： Léon G. Blaise Savadogo Aminata Zombra Cécile Tamini Maurice Kinda Philipe Donnen Centre Hospitalier Régional Banfora Burkina Faso CR3—Politiques et Systèmes de Santé—Santé Internationale School of Public Health Université Libre de Bruxelles Bruxelles Belgique department of epidemiology and Public Health—Child and Mother Health Nutrition and Survival Unit—Institut Supérieur des Sciences de la Santé Université Polytechnique Bobo Dioulasso Burkina Faso ecole National de Santé Publique Bobo Dioulasso Burkina Faso

Individual causes and community determinants are synergic in maternal death occurrence. This study aimed to identify maternal mortality risk factors in a regional hospital. Material and Methods: This was a retrospective cohort study from data of 1807 hospitalized women. To identify maternal mortality risks factors, mortality hazard ratio (HR CI95%) has been calculated in univariate analysis and Cox proportional hazard model. Results: During hospitalization, 30 maternal deaths occurred. From Cox regression, adjusted mortality HR confirmed that women age older than 35 (HR = 2.5, CI95%: [1.2-5.7] and younger than 19 (HR = 3.02, CI95%: [1.5-6.7]);distance to hospital ≥10 Km (HR = 4.1, CI95%: [1.8-9.4];multiple deliveries (HR = 2.4, CI95%: [1.1-7.3]), less ante natal care (etrical maternal mortality directs causes (HR = 2.31, CI95%: [1.7-6.21]) and emergently reference (HR = 3.5, CI95%: [1.8-8.32]) were maternal mortality risk factors. Conclusion: In this regional hospital of low income country, identified maternal mortality factors are related to women socio-economic determinants and quality prenatal or obstetric care access. Interventions to reduce maternal mortality rate should be conducted within both household and women socio-economic status development and in maternal health and obstetric care strengthening.

关键词： Maternal Mortality Risk Factors Regional Hospital Burkina Faso

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Numerical investigation of spallation neutrons generated from petawatt-scale laser-driven proton beams

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Matter and Radiation at extremes 2022年第2期7卷 8-17页

作者： B.Martinez S.N.Chen S.Bolaños N.Blanchot G.Boutoux W.Cayzac C.Courtois X.Davoine A.Duval V.Horny I.lantuejoul L.Le deroff P.e.Masson-laborde G.Sary B.Vauzour R.Smets L.Gremillet J.Fuchs LULI-CNRS CEAUPMC Univ Paris 06:Sorbonne UniversitéEcole PolytechniqueInstitut Polytechnique de ParisF-91128 Palaiseau CedexFrance CeA DAMDIFF-91297 ArpajonFrance Horia Hulubei National Institute of Physics and Nuclear engineering Bucharest-MagureleRomania CeA DAMCESTAF-33114 Le BarpFrance UniversitéParis-Saclay CEALMCE91680 Bruyères-le-ChâtelFrance LPP Sorbonne UniversitéCNRSEcole PolytechniqueF-91128 Palaiseau CedexFrance

laser-driven neutron sources could offer a promising alternative to those based on conventional accelerator technologies in delivering compact beams of high brightness and short *** examine this through particle-in-cell and Monte Carlo simulations that model,respectively,the laser acceleration of protons from thin-foil targets and their subsequent conversion into neutrons in secondary lead *** parameters relevant to the 0.5 PW LMJ-PeTAL and 0.6–6 PW Apollon systems are *** to its high intensity,the 20-fs-duration 0.6 PW Apollon laser is expected to accelerate protons up to above 100MeV,thereby unlocking efficient neutron generation via spallation *** a result,despite a 30-fold lower pulse energy than the LMJ-PeTAL laser,the 0.6 PW Apollon laser should perform comparably well both in terms of neutron yield and ***,we predict that very compact neutron pulses,of∼10 ps duration and∼100μm spot size,can be released provided the lead convertor target is thin enough(∼100μm).These sources are characterized by extreme fluxes,of the order of 10^(23) n cm^(−2) s^(−1),and even ten times higher when using the 6 PW Apollon *** values surpass those currently achievable at large-scale accelerator-based neutron sources(∼10^(16) n cm^(−2) s^(−1)),or reported from previous laser experiments using low-Z converters(∼10^(18) n cm^(−2) s^(−1)).By showing that such laser systems can produce neutron pulses significantly brighter than existing sources,our findings open a path toward attractive novel applications,such as flash neutron radiography and laboratory studies of heavy-ion nucleosynthesis.

关键词： thereby attractive extreme

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Synchrotron refractive-index microradiography of human liver cancer tissue

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Chinese Science Bulletin 2005年第22期50卷 2657-2661页

作者： TONG Yongpeng ZHANG Guilin LI Yan HWU Yeukuang TSAI Wenli Je Jung Ho Margaritondo G YUAN Dong Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China Institute of Physics Academia Sinica Nankang Taipei China department of Material Science and engineering Pohang Universty of Science and Technology Pohang Korea IPA-ecole polytechnique Federale de lausanne (ePFL) CH-1015 Lausanne Switzerland Shanghai CDC Shanghai 200336 China

Three human liver tissue samples (～5 mm × 40 mm × 20 mm) were excised from a cancer patient's liver during surgery. The microradiology analysis was performed with a non-standard approach on a synchrotron. High-resolution refractive-index edge-enhanced microradiographs that cover a larger volume of the liver tissue sample were obtained. The cancer tissue and normal tissue could be clearly identified and distinguished based on their different textures. Furthermore, new blood vessel hyperplasia was found near the cancer area. Blood vessels with a diameter smaller than 20 μm could be identified. These findings were fully consistent with the histopathological examination of the same area. Microradiographs of the newly formed blood vessels at different angles were also obtained. This result shows that it is possible to further develop this approach into a technique of microradiographic imaging for clinic diagnosis of liver cancer at the early stage.

关键词：肝癌同步加速器折射系数 X射线显微照相术组织病理学

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Photonic properties of novel Yb3＋ doped germanium-lead oxyfluoride glass-ceramics for laser cooling applications

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Frontiers of Optoelectronics 2018年第2期11卷 189-198页

作者： lauro J. Q. MAIA Jyothis THOMAS Yannick LedeMI Kummara V. KRISHNAIAH denis SeLeTSKIY Younes MeSSADdeQ Raman KASHYAP Instituto de Fisica Universidade Federal de Goias Av. Esperanga 1533 Campus Samambaia Goiania GO 74690-900 Brazil department of electrical engineering Ecole Polytechnique de Montrral P.O. Box 6079 Station Centre-ville Montreal QC H3C 3A7 Canada department of engineering Physics Ecole Polytechnique de Montrral P.O. Box 6079 Station Centre-ville Montreal QC H3C 3A7 Canada Centre d'Optique Photonique et Laser 2375 Rue de la Terrasse Universite Laval Qurbec QC G1V 0A6 Canada

Abstract In recent years, our research group has developed and studied new rare-earth doped materials for the promising technology of solid-state laser cooling, which is based on anti-stokes fluorescence. To the best of our knowledge, our group is the only one in Canada leading the research into the properties of nanoparticles, glasses and glass-ceramics for optical refrigeration appli- cations. In the present work, optical properties of 50GeO2- 30PbF2-18PbO-2YbF3 glass-ceramics for laser cooling are presented and discussed as a function of crystallization temperature. Spectroscopic results show that samples have near infrared photoluminescence emission due to the 2F5/2 - 2F7/2 Yb3＋ transition, centered at -1016 nm with an excitation wavelength of 920 nm or 1011 nm, and the highest photoluminescence emission efficiency occurs for heat-treatment for 5 h at 350℃. The internal photolumi- nescence quantum yield varies between 99% and 80%, depending on the temperature of heat-treatment, being the most efficient under 1011 nm excitation. The 2F5/2 lifetime increases from 1.472 to 1.970 ms for heat treatments at 330℃ to 350℃, respectively, due to energy trapping and the low phonon energy of the nanocrystals. The sample temperature dependence was measured with a fiber Bragg grating sensor, as a function of input pump laser wavelength and processing temperature. These measure- ments show that the heating process approaches near zero for an excitation wavelength between 1020 and 1030 nm, which is an indication that phonons are removed effectivelly from the glass-ceramic materials, and they can be used for optical laser cooling applications. On theother hand, the temperature increase as a function of input laser power into samples remains constant between 920 and 980 nm wavelength excitation, a temperature variation of 36 K/W （temperature of 58℃/W） was attained under excitation at 950 nm, showing a possible use for biomedical applications to be explored.

关键词： optical refrigeration oxyfluoride glass-cera-mics Yb3+ doping quantum yield infrared emission lifetime

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High-brightness polarized light-emitting diodes

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Light(Science & Applications) 2012年第1期1卷 72-78页

作者： elison Matioli Stuart Brinkley Kathryn M Kelchner Yan-Ling Hu Shuji Nakamura Steven denBaars James Speck Claude Weisbuch department of electrical engineering and Computer Science Massachusetts Institute of TechnologyCambridgeMAUSA department of electrical and Computer engineering University of CaliforniaSanta BarbaraCAUSA Materials department University of CaliforniaSanta BarbaraCAUSA laboratoire de Physique de la Matie`re Condense´e CNRSEcole PolytechniquePalaiseauFrance

Light-emitting diodes are becoming the alternative for future general lighting applications,with huge energy savings compared to conventional light sources owing to their high efficiency and *** light sources would largely enhance the efficiency in a number of applications,such as in liquid-crystal displays,and also greatly improve contrast in general illumination due to the reduction in indirect ***,we demonstrate light-emitting diodes presenting high-brightness polarized light emission by combining the polarization-preserving and directional extraction properties of embedded photonic-crystals applied to non-polar gallium nitride.A directional enhancement of up to 1.8-fold was observed in the total polarized light emission together with a high polarization degree of 88.7%at 465 *** discuss the mechanisms of polarized light emission in non-polar gallium nitride and the photonic-crystal design rules to further increase the light-emitting diode *** work could open the way to polarized white-light emitters through their association with polarization-preserving down-converting phosphors.

关键词： GaN LeDs m-plane polarized light

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Potential Risk of Transmission of escherichia coli and Salmonella spp. Infections by the Musca domestica Fly and the Periplaneta americana Cockroach in the City of Cotonou (South Benin)

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Advances in Microbiology 2023年第9期13卷 448-461页

作者： Tatcheme Filemon TatTokponnon Bidossessi Brunelle ella Agassounon Daton Sylvain Kougblenou Razak Osse Victorien Dougnon Calmette Nouwagbe Daga Justin Kossou Idayath Joachelle Gounou Yerima Festus Houessinon Sare Dabou Zoulkifilou Martin Akogbeto ecole polytechnique d’Abomey-Calavi Abomey-Calavi Benin Centre de Recherche entomologique de Cotonou Cotonou Benin Unité de Recherche en Microbiologie Appliquée et Pharmacologie des Substances Naturelles Université d’Abomey-Calavi Abomey-Calavi Benin Section Hygiène des eaux et Aliments Ministère de la Santé Cotonou Benin ecole de Gestion et d’exploitation des Systèmes d’elevage Université Nationale d’Agriculture Kétou Bénin

Background: The occurrence of bacterial infections sometimes involves synanthropic flies and cockroaches, as mechanical vectors of pathogenic microorganisms. The aim of this study was to identify the different species of flies and cockroaches that cohabit with humans in the city of Cotonou and determine the contribution of Musca domestica and Periplaneta americana in the transmission of bacteria responsible for infections in humans. Methods: Capture sessions during the day for flies and at night for cockroaches were carried out in 4 arrondissements of the city of Cotonou. The insects collected were transported to the Center of Research entomological of Cotonou for identification, then sent to the Section Hygiene of Water and Food for microbiological analysis, enumeration and testing for human pathogenic bacteria. Results: A total of 351 flies and 26 cockroaches were collected at the sites, including two synanthropic species belonging to two families each. Musca domestica and Periplaneta americana were the most abundant species found after identification in the city of Cotonou. Thermo-tolerant coliforms and escherichia coli were found on all specimens at varying concentrations. Salmonella spp. bacteria were identified in the fly population from the Dantokpa dump. Conclusion: Flies and cockroaches can transmit microorganisms to humans. The presence of Salmonella spp. among the specimens revealed that infections frequently caused by contaminated food or water are also transmitted to humans by flies. The presence of these germs on flies and cockroaches represents a potential risk of mechanical transmission to humans. It is, therefore, essential to continue investigations in order to assess the species of bacteria propagated, improve control strategies against these troublesome insects and adopt better hygiene conditions for better living.

关键词： Musca domestica Periplaneta americana Mechanical Transmission Salmonella spp. and escherichia coli Infections Cotonou

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deep-UV fluorescence lifetime imaging microscopy

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Photonics Research 2015年第5期3卷 283-288页

作者： Christiaan J.de Jong Alireza lajevardipour Mindaugas Gecevicius Martynas Beresna Gediminas Gervinskas Peter G.Kazansky Yves Bellouard Andrew H.A.Clayton Saulius Juodkazis Centre for Micro-Photonics Faculty of Science Engineering and Technology Swinburne University of Technology department of Mechanical engineering Eindhoven University of Technology Optoelectronics Research Centre University of Southampton Melbourne Centre for Nanofabrication ecole polytechnique Fédérale de lausanne Rue de la Maladiére 71b Center for Nanotechnology King Abdulaziz University

A novel fluorescence lifetime imaging microscopy(FLIM) working with deep UV 240–280 nm wavelength excitations has been developed. UV-FLIM is used for measurement of defect-related fluorescence and its changes upon annealing from femtosecond laser-induced modifications in fused silica. This FLIM technique can be used with microfluidic and biosamples to characterize temporal characteristics of fluorescence upon UV excitation, a capability easily added to a standard microscope-based FLIM. UV-FLIM was tested to show annealing of the defects induced by silica structuring with ultrashort laser pulses. Frequency-domain fluorescence measurements were converted into the time domain to extract long fluorescence lifetimes from defects in silica.

关键词： UV deep-UV fluorescence lifetime imaging microscopy

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Forced electrocodeposition of Silica Particles into Nickel Matrix by Horizontal Impinging Jet Cell

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Journal of Materials Science and Chemical engineering 2017年第2期5卷 51-63页

作者： Désiré M. K. Abro Pierre Jean Marie Richard Dable Véronique Amstutz edith Kouassi Kwa-Koffi Hubert Girault Facult&eacute des Sciences des Structures de la Mati&egrave re et de Technologie Universit&eacute F&eacute lix HOUPHOUeT-BOIGNY Abidjan C&ocirc te d'Ivoire D&eacute partement de G&eacute nie M&eacute canique et energ&eacute tique Institut National Polytechnique F&eacute lix HOUPHOUeT-BOIGNY Yamoussoukro C&ocirc te d'ivoire Institut des sciences et ing&eacute nierie chimiques Ecole Polytechnique F&eacute d&eacute rale de lausanne Sion Suisse

The improvement of silica particle codeposition into a nickel electrodeposited composite coating (eCC) by a double face horizontal impinging jet cell (IJC) has been studied. The microstructure of coatings was examined by means of scanning electron microscopy performed in backscattered electron mode. The embedded particles distribution was shown to be the densest and the most uniform in laminar low flow mode and when the nozzle is at a distance of 5 mm close from the cathode. excrescences observed on the composite surface are due to the wave-like flow of the jet on the cathode surface. The silica content of the nickel composite coatings was assessed by energy dispersive X-ray spectroscopy. The amount of particles embedded in the coating decreases with an increasing Reynolds number and as the nozzle-to-sample distance d becomes larger. A maximum rate of 4.43 wt% of silica has been successfully loaded at a distance d equal to 5 mm in the Ni-SiO2 composite coating.

关键词： electrocodeposition Nickel-Silica Composite Coatings Impinging Jet Cell Hydrodynamics

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Phytochemical Screening, Antioxidant Activity and Safety of Petroselinum crispum (Mill.) AW Hill Apiaceae Leaves Grown in Benin

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Open Journal of Applied Sciences 2023年第1期13卷 36-50页

作者： Germaine Sènandjro Gnintoungbe Thierry C. Marc Medehouenou Ferdinand Adounkpe Casimir Akpovi Frédéric Loko Unité de Recherche sur les Maladies Non Transmissibles et le Cancer (UR-MNTC) Laboratoire de Recherche en Biologie Appliquée Ecole Polytechnique d’Abomey-Calavi Université d’Abomey-Calavi Cotonou Bénin laboratoire National des Stupéfiants et de Toxicologie (LNST) Centre Béninois de la Recherche Scientifique et de l’Innovation (CBRSI) Université d’Abomey-Calavi (UAC) Cotonou Bénin

Petroselinum crispum (Mill.) AW Hill Apiaceae (Parsley) is a plant species commonly used for its culinary value, but little is known about its phytochemical composition and antioxidant properties. This study aimed to deepen knowledge of the Petroselinum crispum leaves (LPc) grown and consumed in Benin. The phytochemical screening of the LPc powder was done according to the method of Houghton and Raman at the laboratory of Pharmacognosy and essential Oils of the Institute of Applied Biomedical Sciences in Benin. The antioxidant activity (IC50) was evaluated by the DPPH reduction test. Phytochemical screening revealed the presence of chemical groups such as catechin tannins, gallic tannins, flavones, saponins, mucilages, coumarins, reducing agents and O-heterosides with reduced genins in the LPc powder. The aqueous extract of LPc showed antioxidant activity with an IC50 = 63.66 μg/mL and was found to be less active than ascorbic acid (IC50 = 0.111 μg/mL). No acute oral toxicity was observed and the LD50 of the aqueous extract of LPc is estimated to be greater than 5000 mg/kg in the Wistar rat. The absence of toxicity, its antioxidant activity associated with its richness in active ingredients makes Petroselinum crispum a promising species suitable for safe long-term use as food.

关键词： Parsley Phytochemistry Antioxidant Properties Toxicity Wistar Rat

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Category Theoretic Properties of the A. Rényi and C. Tsallis entropies

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Journal of Modern Physics 2016年第2期7卷 251-266页

作者： György Steinbrecher Alberto Sonnino Giorgio Sonnino Physics department Faculty of Science University of Craiova Craiova Romania Karlsruhe Institute of Technologies (KIT) Department of Electrical Engineering and Information Technologies Karlsruhe Germany ecole polytechnique de Louvain (ePL) Université Catholique de Louvain (UCL) Louvain-la-Neuve Belgium department of Theoretical Physics and Mathematics Université Libre de Bruxelles (ULB) Brussels Belgium

The problem of embedding the Tsallis, Rényi and generalized Rényi entropies in the framework of category theory and their axiomatic foundation is studied. To this end, we construct a special category MeS related to measured spaces. We prove that both of the Rényi and Tsallis entropies can be imbedded in the formalism of category theory by proving that the same basic partition functional that appears in their definitions, as well as in the associated Lebesgue space norms, has good algebraic compatibility properties. We prove that this functional is both additive and multiplicative with respect to the direct product and the disjoint sum (the coproduct) in the category MeS, so it is a natural candidate for the measure of information or uncertainty. We prove that the category MeS can be extended to monoidal category, both with respect to the direct product as well as to the coproduct. The basic axioms of the original Rényi entropy theory are generalized and reformulated in the framework of category MeS and we prove that these axioms foresee the existence of an universal exponent having the same values for all the objects of the category MeS. In addition, this universal exponent is the parameter, which appears in the definition of the Tsallis and Rényi entropies. It is proved that in a similar manner, the partition functional that appears in the definition of the Generalized Rényi entropy is a multiplicative functional with respect to direct product and additive with respect to the disjoint sum, but its symmetry group is reduced compared to the case of classical Rényi entropy.

关键词： Rényi entropy Generalized Rényi entropy Measured Spaces Monoidal Category

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