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Impact of a Mass Campaign on the Evolution of the Fourth Wave of the Covid-19 Pandemic in the Central African republic

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Journal of Tuberculosis research 2024年第3期12卷 142-150页

作者： Clotaire Donatien Rafaï pierre Somse Wilfrid Sylvain Nambei Ernest Lango-Yaya Marie-Roseline Darnycka Belizaire Ulrich Vickos Narcisse Patrice Komas Oscar Senzongo Luc Salva Heredeibona Ulrich Jeffrey Kotemossoua Rabbi Mermoz Senekian Simon Pounguinza Jephté Estimé Kaleb Christian-Diamant Mossoro-Kpinde Alain le Faou jean De Dieu Longo Norbert Richard Ngbale Abdoulaye Sepou François-Xavier Mbopi-Keou Gérard Grésenguet Boniface Koffi National Laboratory of Clinical Biology and Public Health Bangui Central African Republic Faculty of Health Sciences University of Bangui Bangui Central African Republic Ministry of Health and Population Bangui Central African Republic World Health Organization Bangui Central African Republic Pasteur Institute of Bangui Bangui Central African Republic Faculty of Medicine Midwifery and Health Professions University of Lorraine Nancy France Faculty of Medicine and Biomedical Sciences University of Yaounde I Yaounde Cameroun Community University Hospital Center of Bangui Bangui Central African Republic

Objective: In the context of increasing cases despite vaccination campaigns, a survey was conducted in the Bangui population from January 17 to 26, 2022, to evaluate the strains of Severe Acute respiratory Infection Coronavirus 2 (SARS-Cov-2) circulating in a healthy population. Materials and methods: This study was conducted by taking nasopharyngeal samples from randomly selected volunteers. Antigen detection was performed systematically, and RT-PCR was done on the positive samples. results and discussion: We collected 2,554 samples. Thirty were found RT-PCR positive (1.2%) and sent for viral genome sequencing. Twenty-eight SARS-Cov-2 strains belonged to the Omicron type, and only 2 to the Delta type. Conclusion: Thus, infections were uncommon in the tested population, but the presence of Omicron and Delta types raises concerns that vaccination may not be effective in fighting the virus, and newly designed vaccines should be implemented to better protect the population at risk of infection and reinfection by these variants.

关键词： COVID-19 SARS-CoV-2 Variants

Large group-index bandwidth product empty core slow light photonic crystal waveguides for hybrid silicon photonics

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Frontiers of Optoelectronics 2014年第3期7卷 376-384页

作者： Charles caer Xavier le ROUX Samuel SERNA Weiwei ZHANG Laurent VIVIEN Eric CASSAN Institut d'Electronique Fondamentale University Paris-Sud CNRS UMR 8622 Bat. 220 91405 Orsay Cedex France

This paper investigates the slow light propaga- tion in silicon on insulator wide slot photonic crystal waveguides （PCWs）. Two design schemes are presented, relying on the dispersion engineering of hole lattice and slot, respectively. Mode patterns and band diagrams are calculated by 3D-plane wave expansion method. Then, coupling and slow light propagations are modeled using finite difference time domain method in a full Mach- Zehnder interferometer （MZI）. results show high amplitudes interference fringes and high coupling efficiencies. Fabrication and measurement of devices lead to slow light propagation with group indices above 50, while multiple scattering and localized modes near the band edge also observed. This study provides insights for losses in hollow core slot high group index waveguides.

关键词： silicon photonics photonic crystals (PC) slot waveguides slow waves

Increasing the effectiveness of intracerebral injections in adult and neonatal mice: a neurosurgical point of view

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Neuroscience Bulletin 2015年第6期31卷 685-696页

作者： Bertrand Mathon Mérie Nassar jean Simonnet Caroline le Duigou Stéphane Clemenceau Richard Miles Desdemona Fricker Department of Neurosurgery Groupe Hospitalier Universitaire de La Pitié-SalpêtrièreAPHPF-75013ParisFrance Inserm U 1127F-75013ParisFrance CNRS UMR 7225F-75013ParisFrance Sorbonne Universités UPMC Univ Paris 06UMR S 1127F-75013ParisFrance Institut du Cerveau et de la Moelle épinière ICMF-75013ParisFrance

Intracerebral injections of tracers or viral constructs in rodents are now commonly used in the neurosciences and must be executed perfectly. The purpose of this article is to update existing protocols for intracerebral injections in adult and neonatal mice. Our procedure for stereotaxic injections in adult mice allows the investigator to improve the effectiveness and safety, and save time. Furthermore, for the first time, we describe a two-handed procedure for intracerebral injections in neonatal mice that can be performed by a single operator in a very short time. Our technique using the stereotaxic arm allows a higher precision than freehand techniques previously described. Stereotaxic injections in adult mice can be performed in 20 min and have 〉90% efficacy in targeting the injection site. Injections in neonatal mice can be performed in 5 min. Efficacy depends on the difficulty of precisely localizing the injection sites, due to the small size of the animal. We describe an innovative, effortless, and reproducible surgical protocol for intracerebral injections in adult and neonatal mice.

关键词： rodents surgery neurosciencesstereotaxic injection newborn mice neonatal brain

Expert group syndrome at high altitude

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Sports Medicine and Health Science 2022年第3期4卷 215-218页

作者： jean-Paul Richalet Marie-Anne Magnan Alice Gavet pierre Lafère UniversitéSorbonne Paris Nord Laboratoire Hypoxie et PoumonUMR INSERM U1272BobignyFrance Institut National des Sports de l’Expertise et de la PerformancePôle médicalParisFrance Hôpitaux universitaires de Genève Département de médecine aiguëUnitéde médecine subaquatique et hyperbareGenevaSwitzerland Hôpitaux du Mont-Blanc Soins de suite et réadaptationChamonixFrance Universitéde Bretagne Occidentale Laboratoire ORPHYEA 44324BrestFrance HauteÉcole Bruxelles-Brabant(HE2B) EnvironmentalOccupationalAgeing(Integrative)Physiology LaboratoryBrusselsBelgium

During a training session for the university diploma of Mountain medicine delivered by University Sorbonne Paris Nord for medical doctors,one of the participants developed signs of maladaptation to high altitude at 3600 m,the severity of which was incorrectly *** was sparingly given by the patient(an anesthetist)to several of his colleagues and no one was in charge to collect clinical data,take a history,and provide appropriate *** combination of the absence of designation of a supervising doctor and the difficulty of communicating with the patient led to a lack of coordinated management and to an evolution of the symptoms towards severe acute mountain ***,the very rapid management of the patient and a rapid helicopter evacuation,as soon as the symptoms worsened towards the onset of a suspected high altitude cerebral and/or pulmonary edema,allowed rapid resolution without ***,medical,psychological,and managerial factors led to this Expert Group Syndrome.

关键词： Acute mountain sickness High altitude cerebral edema Psychology Group management

Palladium-catalyzed hydrosilylation of ynones to access siliconstereogenic silylenones by stereospecific aromatic interactionassisted Si–H activation

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Science China Chemistry 2021年第5期64卷 761-769页

作者： Jia-le Xie Zheng Xu Han-Qi Zhou Yi-Xue Nie Jian Cao Guan-Wu Yin jean-Philippe Bouillon Li-Wen Xu Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education Key Laboratory of Organosilicon Material Technology of Zhejiang ProvinceHangzhou Normal UniversityHangzhou 311121China State Key Laboratory for Oxo Synthesis and Selective Oxidation Suzhou Research Institute(SRI)Lanzhou Institute of Chemical Physics(LICP)University of the Chinese Academy of Sciences(UCAS)Lanzhou 730000China Normandie University INSA RouenUNIROUENCNRSCOBRA(UMR 6014)Rouen 76000France

Hydrosilylation is one of the most important reactions in synthetic chemistry and ranks as a fundamental method to access organosilicon compounds in industrial and academic ***,the enantioselective construction of chiral-at-silicon compounds via catalytic asymmetric hydrosilylation remained limited and *** we report a highly enantioselective hydrosilylation of ynones,a type of carbonyl-activated alkynes,using a palladium catalyst with a chiral binaphthyl phosphoramidite *** stereospecific hydrosilylation of ynones affords a series of silicon-stereogenic silylenones with up to 94%yield,>20:1 regioselectivity and 98:2 *** density functional theory(DFT)calculations were conducted to elucidate the reaction mechanism and origin of high degree of stereoselectivity,in which the powerful potential of aromatic interaction in this reaction is highlighted by the multiple C–H-πinteraction and aromatic cavity-oriented enantioselectivitydetermining step during desymmetric functionalization of Si–H bond.

关键词： asymmetric catalysis DFT calculations hydrosilylation silicon-stereogenic vinylsilanes aromatic interaction

TRPV1 and TRPA1 in cutaneous neurogenic and chronic inflammation： pro-inflammatory response induced by their activation and their sensitization

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Protein & Cell 2017年第9期8卷 644-661页

作者： Olivier Gouin Killian L'Herondelle Nicolas lebonvallet Christelle le Gall-lanotto Mehdi Sakka Virginie Buhe Emmanuelle piee-Gautier jean-Luc Carre Luc lefeuvre Laurent Misery~,Raphaele le Garrec Laboratory on Interaction Neurons-Keratinocytes (LINK) University of Western Brittany 29200 Brest France Uriage Dermatological Laboratories 92400 Courbevoie France

Cutaneous neurogenic inflammation （CNI） is inflammation that is induced （or enhanced） in the skin by the release of neuropeptides from sensory nerve endings. Clinical manifestations are mainly sensory and vascular disorders such as pruritus and erythema. Transient receptor potential vanilloid 1 and ankyrin 1 （TRPV1 and TRPA1, respectively） are non-selective cation channels known to specifically participate in pain and CNI. Both TRPV1 and TRPA1 are co-expressed in a large subset of sensory nerves, where they integrate numerous noxious stimuli. It is now clear that the expression of both channels also extends far beyond the sensory nerves in the skin, occuring also in keratinocytes, mast cells, dendritic cells, and endothelial cells. In these non-neu- ronal cells, TRPV1 and TRPA1 also act as nociceptive sensors and potentiate the inflammatory process. This review discusses the role of TRPV1 and TRPA1 in the modulation of inflammatory genes that leads to or maintains CNI in sensory neurons and non-neuronal skin cells. In addition, this review provides a summary of current research on the intracellular sensitization pathways of both TRP channels by other endogenous inflammatory mediators that promote the self-maintenance of CNI.

关键词： sensory nervenflammation inflammatory geneneurogenic skinregulation pruritus

Mechanism of friction reduction of unsaturated fatty acids as additives in diesel fuels

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Friction 2013年第3期1卷 252-258页

作者： jean Michel MARTIN Christine MATTA Maria-Isabel De Barros BOUCHET Cyrielle FOreST Thierry le MOGNE Thomas DUBOIS Michael MAZARIN Laboratory of Tribology and System Dynamics Ecole Centrale de Lyon69134 EcullyFrance TOTAL CReSBP2269360 Solaize CedexFrance

This paper investigates the effect of unsaturated fatty acid additives on the lubricating properties of a biodiesel,composed of a blend of fatty acid methyl esters(FAMEs)and a conventional diesel *** presence of fatty acids as additives for biodiesel improves their lubricating properties at elevated temperature *** formation of a protective lubricating tribochemical film on the steel contact surfaces has been *** temperature conditions and possibly oxygen are needed to form this film that reduces friction and limits *** analytical tools have revealed the insulating nature of the formed tribofilm and its chemical ***-induced reticulation is thought to play a major role in the growth of this insulating film.

关键词： biodiesel low friction fatty acids tribochemistry surface analysis

From Farming to Engineering： The Microbiota and Allergic Diseases

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Engineering 2017年第1期3卷 98-109页

作者： Dominique Angèle Vuitton jean-Charles Dalphin University Bourgogne Franche-Comte Besancon 25030 France Anergology Network of Franche-Comte Besancon 25030 France

The steady increase of lgE-dependent allergic diseases after the Second World War is a unique phenomenon in the history of humankind. Numerous cross-sectional studies, comprehensive longitudinal cohort studies of children living in various types of environment, and mechanistic experimental studies have pointed to the disappearance of ＂protective factors＂ related to major changes in lifestyle and environment. A common unifying concept is that of the immunoregulatory role of the gut microbiota. This review focuses on the protection against allergic disorders that is provided by the farming environment and by exposure to microbial diversity. It also questions whether and how microbial bioengineering will be able in the future to restore an interplay that was beneficial to the proper immunological development of children in the past and that was irreversibly disrupted by changes in lifestyle. The protective ＂farming environment＂ includes independent and additional influences： contact with animals, stay in barns/stables, and consumption of unprocessed milk and milk products, by mothers during pregnancy and by children in early life. More than the overall quanti- ty of microbes, the biodiversity of the farm microbial environment appears to be crucial for this protection, as does the biodiversity of the gut microbiota that it may provide. Use of conventional probiotics, especially various species or strains of Lactobacillus and Bifidobacterium, has not fulfilled the expectations of allergists and pediatricians to prevent allergy. Among the specific organisms present in cowsheds that could be used for prevention, Acinetobacter （A.） lwoffii F78, Lactococcus （ L.） lactis G121, and Staphylococcus （S.） sciuri W620 seem to be the most promising, based on experimental studies in mouse models of allergic respiratory diseases. However, the development of a new generation of probiotics based on very productive research on the farming environment faces several obstacles that cannot b

关键词： Allergy Farming Microbial biodiversity Immune regulation Microbiota Translational research

Plasma phospholipid transfer protein （PLTP） modulates adaptive immune functions through alternation of T helper cell polarization

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Cellular & Molecular Immunology 2016年第6期13卷 795-804页

作者： Catherine Desrumau Stephanie lemaire-Ewing Nicolas Ogier Akadiri Yessoufou Arlette Hammann Anabelle Sequeira-le Grand Valerie Deckert jean-Paul Pais de Barros Naig le Guern Julien Guy Naim A Khan Laurent Lagrost INSERM UMR866 - F21079 Dijon France Univ. Bourgogne Franche-Comte F-21000 Dijon France LipSTIC LabEx Fondation de Cooperation Scientifique Bourgogne-Franche Comte F-21000 Dijon France CHU Hopital du Bocage Dijon France plateforme de Cytometrie en Flux Universite de Bourgogne Dijon France

Objective： Plasma phospholipid transfer protein （PLTP） is a key determinant of lipoprotein metabolism, and both animal and human studies converge to indicate that PLTP promotes atherogenesis and its thromboembolic complications. Moreover, it has recently been reported that PLTP modulates inflammation and immune responses. Although earlier studies from our group demonstrated that PLTP can modify macrophage activation, the implication of PLTP in the modulation of T-cell-mediated immune responses has never been investigated and was therefore addressed in the present study. Approach and results： In the present study, we demonstrated that PLTP deficiency in mice has a profound effect on CD4＋ ThO cell polarization, with a shift towards the anti-inflammatory Th2 phenotype under both normal and pathological conditions. In a model of contact hypersensitivity, a significantly impaired response to skin sensitization with the hapten-2,4-dinitrofluorobenzene （DNFB） was observed in PLTP-deficient mice compared to wild-type （WT） mice. Interestingly, PLTP deficiency in mice exerted no effect on the counts of total white blood cells, lymphocytes, granulocytes, or monocytes in the peripheral blood. Moreover, PLTP deficiency did not modify the amounts of CD4＋ and CD8＋ T lymphocyte subsets. However, PLTP-deficiency, associated with upregulation of the Th2 phenotype, was accompanied by a significant decrease in the production of the pro-Thl cytokine interleukin 18 by accessory cells. Conclusions： For the first time, this work reports a physiological role for PLTP in the polarization of CD4＋ T cells toward the pro-inflammatory Th I phenotype.

关键词： lipid transfer protein lymphocyte polarization T cell