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Evidence of Iron Mineralization Channels in the Messondo Area (Centre-Cameroon) Using Geoelectrical (DC &IP) Methods: A Case study

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International Journal of Geosciences 2014年第3期5卷 346-361页

作者： Ngoumou Paul Claude Ndougsa-Mbarga Théophile assembe stéphane patrick Kofane Timoleon Crepin Department of Physics Advanced Teachers’ Training College University of Yaoundé I Yaoundé Cameroon Department of Physics Faculty of Science University of Yaoundé I Yaoundé Cameroon

A geophysical survey was conducted in the Kelle-Bidjocka village, Messondo subdivision, in the Centre Region, Cameroon. The data acquisition was made by combining Schlumberger profiling and electrical soundings along six (06) profiles of 1500 m in length for a total of 64 geoelectrical stations’ survey conducted through a variable mesh 100 m × 200 m, or 100 m × 300 m. The equipment used is the DC resistivimeter Syscal Junior 48 (Iris Instrument). Processing and modelling of field data are made by using the Res2Dinv, Qwseln and Surfer software. The investigation methods used are electrical resistivity (DC) and induced polarization (IP) methods. The analyses and interpretations have helped to highlight areas of weakness or conductive discontinuities (fractures, faults, shear zones, etc.) in Precambrian gneiss formations, sometimes undergoing weathering processes. They identify the weathering or mineralogical accumulation horizons, the most promising is a mineralization channel identified in the NE-SW direction. The highlighted mineralization is characterized by strong gradients of chargeability or polarization. Samples and other geological evidences observed in the area are used to associate the most polarizable structures with ferriferous formations. Weakly polarizable and particularly conductive backgrounds identified by the inverse pseudo-sections are thought to be sulphate minerals or groundwater targets for future hydrogeological studies.

关键词： Direct Current IP Method Geoelectrical Surveys Resistivity Chargeability Shear Zones Iron Mineralization

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High-Precision structural Map of Southeast Cameroon Using Phase Filters on Potential Gravimetric Data

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Open Journal of Earthquake Research 2022年第4期11卷 89-107页

作者： Nzeuga Alain Rodrigue Bisse Salomon Bertrant Amaya Adama Kenfack Fokem Alpha Baster Ngah Christian Gislain Leonel Ndjounguep Juscar Nanfa Tefak Fatoumata Maelle Ngoumou Paul Claude assembe stéphane patrick Pokam Kengni Serge Hugues Department of Petroleum Gas and Exploration School of Geology and Mining Engineering University of Ngaoundere Meiganga Cameroon Department of Geological Mapping and Geomatic School of Geology and Mining Engineering University of Ngaoundere Meiganga Cameroon Department of Mining Geology School of Geology and Mining Engineering University of Ngaoundere Meiganga Cameroon Postgraduate School of Science Technology and Geosciences University of Yaounde I Yaounde Cameroon Institute of Mining and Geological Research Ministry of Scientific Research Yaounde Cameroon Department of Geophysics School of Geology and Mining Engineering University of Ngaoundere Meiganga Cameroon Department of Physics Faculty of Science University of Bamenda Bambili Cameroon

The south-east of Cameroon encompasses a wide variety of geological structures among which we can cite the Congo Craton (CC), the Sanaga Fault (SF), the Yaoundé Domain, the Panafrican belt, the Protozoic series and the Dja complex. The presence of all these structures justifies the great tectonic activity to which this area was subject from the rupture of Pangea to the creation of the different plates that exist today. In this work, we will bring out a high-resolution structural map of the study area by applying the qualitative analysis of the phase filters on 200,900 points of gravimetric data obtained from the combination of the XGM2016 and ETOPO1 models. Then, with these same data, we will bring out another structural map with the maxima method called Multi-Scale Horizontal Derivative of Vertical Derivative (MSHDVD) which will be compared to the first in order to show the limits of the MSHDVD method. To do this, we will first use the extension method to highlight the map of residual anomalies, then a combination of derivative, gradient and phase filters to highlight the geological structures responsible for fracturing in this area. Phase filters have the advantage that they make it possible to highlight all the geological edges responsible for the fracturing without taking into account the depth, while the MSHDVD method highlights the existing geological contacts (edges) at depths well defined by the examiner. The structural map obtained with the MSHDVD method shows that the major structural direction in this zone is W-E while that obtained from the interpretation of the phase filters is more precise and shows that the major structural direction in this area would be N-S and this result would be in perfect agreement with the tectonics of East Cameroon.

关键词： Gravimetry Potential Field Data Edge Detection structural Mapping Southeast Cameroon

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On Isodual Double Toeplitz Codes

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Journal of Systems Science & Complexity 2024年第5期37卷 2196-2206页

作者： SHI Minjia XU Li SOLé patrick Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education School of Mathematical Sciences Anhui University state Key Laboratory of Information Security Institute of Information Engineering Chinese Academy of Sciences CNRS University of Aix Marseille Centrale Marseille

Double Toeplitz（shortly DT） codes are introduced here as a generalization of double circulant codes. The authors show that such a code is isodual, hence formally self-dual（FSD）. FSD codes form a far-reaching generalization of self-dual codes, the most important class of codes of rate one-half. Self-dual DT codes are characterized as double circulant or double negacirculant. Likewise, even binary DT codes are characterized as double circulant. Numerical examples obtained by exhaustive search show that the codes constructed have best-known minimum distance, up to one unit, amongst formally self-dual codes, and sometimes improve on the known values. For q = 2, the authors find four improvements on the best-known values of the minimum distance of FSD codes. Over F4an explicit construction of DT codes, based on quadratic residues in a prime field, performs equally well. The authors show that DT codes are asymptotically good over Fq. Specifically, the authors construct DT codes arbitrarily close to the asymptotic Varshamov-Gilbert bound for codes of rate one half.

关键词： Double circulant codes double Toeplitz codes formally self-dual codes isodual codes

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Inducing neuronal regeneration and differentiation via the BDNF/ TrkB signaling pathway: a key target against neurodegenerative diseases?

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Neural Regeneration Research 2024年第3期19卷 495-496页

作者： Mirjana Antonijevic patrick Dallemagne Christophe Rochais Normandie University UNICAENCERMNCaenFrance

Brain-derived neurotrophic factor(BDNF)is one of the neurotrophins,a specific polypeptide growth factor,which plays a crucial role in the proliferation,differentiation,survival,and death of neurons and non-neuronal *** is not only essential to maintain the balance between death on one side and survival of neurons on the other,but also it mediates additional higher-order activities such as learning,memory,and *** is initially synthesized as a precursor protein,proBDNF,that can be secreted as it is or it can be cleaved intracellularly by furin and proconvertases,or extracellularly by extracellular proteases such as matrix metalloprotease-9 and matrix metalloprotease-2,or plasmin to give mature BDNF.

关键词： death diseases degenerative

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Trombe walls with porous medium insertion and their influence on thermal comfort in flats in Cusco,Peru

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Energy and Built Environment 2024年第2期5卷 194-210页

作者： patrick Facelli Sanchez Lisset Mercado Hancco Department of Civil Engineering Faculty of Architecture and Civil EngineeringUniversidad Nacional de San Antonio Abad del Cusco08003 CuscoPeru

The Trombe wall is a passive indirect heating system which should be used in Cusco,Peru to improve thermal conditions against the typical frosts and low temperatures during winter in the high Andean *** to this problem,the use of a modified Trombe wall with insertion of porous medium is proposed to improve thermal comfort in flat buildings in *** research aims to analyse and compare the performance of dwellings without Trombe wall,with traditional Trombe wall,and with Trombe wall with glass and plastic pellets insertion in thermal comfort ***■CFD was used to simulate and analyse the *** simulation was performed with three prototype flats(55 m^(2),75 m^(2) and 95 m^(2))for six months of the *** the results obtained,the level of thermal comfort in the traditional scenarios is low with an average PMV of-1.86,in the scenarios with Trombe wall is good and in the scenarios with Trombe wall with insertion of porous medium is slightly better than the previous one,reaching an average PMV of+0.10 and a temperature of 21.90℃.The study carried out is important because it represents an efficient eco-sustainable heating alternative that improves the thermal comfort sensation in houses during the coldest months of the year.

关键词： Trombe wall thermal comfort porous medium residential buildings computational fluid dynamics

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Multiple sclerosis drug repurposing for neuroregeneration

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Neural Regeneration Research 2024年第3期19卷 507-508页

作者： Peter Göttle Michael Dietrich patrick Küry Department of Neurology Medical FacultyHeinrich-Heine UniversityDüsseldorfGermany

Multiple sclerosis(MS)is an autoimmune disorder of the central nervous system(CNS)and is primarily characterized by immune cell infiltration leading to relapses followed by remission phases and a disease course turning progressive over time with neurodegenerative processes taking over(Amin and Hersh,2023).Of note,beyond relapse-associated worsening early in disease progression independent of relapse activity may arise independently of relapse activity and can occur in all ***-mediated damage of myelin sheaths and the subsequent loss of mature oligodendrocytes are resulting in impaired axonal integrity,neurodegeneration and accounts for irreversible neuronal damage(Kuhlmann et al.,2023).The current landscape of available disease-modifying therapies comprises mainly immunomodulatory drugs that effectively diminish relapses and slow down progression at the onset form of the disease,namely relapsing MS(RMS).In this regard,a number of drugs have been approved as disease-modifying therapies for MS by US Food and Drug Administration and European Medicines Agencies(Box 1).

关键词： drugs impaired irreversible

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Small activating RNA delivery in vivo:Challenges,prospects,and lessons learned from siRNA delivery

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Nano Research 2024年第10期17卷 8990-9002页

作者： Shalini Pandey patrick T.Bednarz Matthias A.Oberli Omid Veiseh Department of Bioengineering William Marsh Rice UniversityHouston 77030USA Xibus Systems 199 Dexter AveWatertown 02472USA

Over the last two decades,small activating RNAs(saRNAs)have quickly moved from discovery to clinical *** as 20 nucleotide long,double stranded RNA,saRNAs have the unique ability to increase gene transcription at the chromatin *** therapeutic modality has great potential as a safe and redosable alternative to gene therapy by increasing target protein expression without changing the genetic *** describe the successful in vivo saRNA delivery vectors and found that similar to small interfering RNA(siRNA)and mRNA targeting tissues outside the liver works best at the end of a *** highlight nanoparticle vectors and RNA-conjugates,where some success has been reported for non-hepatic delivery of saRNAaptamers.

关键词： small activating RNA hepatic bias lipid nanoparticles RNA-conjugates

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A compartment and metapopulation model of Rocky Mountain spotted fever in southwestern United states and northern Mexico

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Infectious Disease Modelling 2024年第3期9卷 713-727页

作者： Laura Backus patrick Foley Janet Foley School of Veterinary Medicine Department of Medicine and EpidemiologyUniversity of CaliforniaDavisCAUSA Department of Biological Sciences California State UniversitySacramentoCAUSA

Rocky Mountain spotted fever(RMSF)is a fatal tick-borne zoonotic disease that has emerged as an epidemic in western North America since the turn of the 21st *** the US south-western border and across northern Mexico,the brown dog tick,Rhipicephalus sanguineus,is responsible for spreading the disease between dogs and *** widespread nature of the disease and the ongoing epidemics contrast with historically sporadic patterns of the *** dogs are amplifying hosts for the Rickettsia rickettsii bacteria,transmission dynamics between dogs and ticks are critical for understanding the *** this paper,we developed a compartment metapopulation model and used it to explore the dynamics and drivers of RMSF in dogs and brown dog ticks in a theoretical region in western North *** discovered that there is an extended lag—as much as two years—between introduction of the pathogen to a naïve population and epidemic-level transmission,suggesting that infected ticks could disseminate extensively before disease is detected.A single large city-size population of dogs was sufficient to maintain the disease over a decade and serve as a source for disease in surrounding smaller *** model is a novel tool that can be used to identify high risk areas and key intervention points for epidemic RMSF spread by brown dog ticks.

关键词： Compartment model Rocky mountain spotted fever SIR model Metapopulation Zoonosis

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Impact of multifocal gas-permeable lens designs on short-term choroidal response, axial length, and retinal defocus profile

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 247-256页

作者： Muteb Alanazi patrick Caroline Amane Alshamrani Maria Liu Optometry Department College of Applied Medical SciencesKing Saud UniversityRiyadh 14813Saudi Arabia College of Optometry Pacific UniversityForest GroveOregon 97116-1756United States Optometry School University of California at BerkeleyCalifornia 94720United States

AIM:To investigate the impact of multifocal gas permeable contact lens(MFGPCL)in various add power and distance/near area allocation on short-term changes of choroidal thickness(ChT),axial length(AL),and retinal defocus profile in young ***:Seventeen young adults(2 males and 15 females;age 23.17±4.48y)were randomly assigned to wear two designs binocularly with a one-week washout period in *** of four MFGPCL designs were *** designs were distance-center that varied in two add power(+1.50 and 3.00 D)and/or two distance zone(DZ)diameters(1.50 and 3.00 mm;design A:DZ 1.5/add 3.0,B:DZ 1.5/add 1.5,C:DZ 3.0/add 3.0,D:DZ 3.0/add 1.5).ChT,AL,and peripheral refraction data were collected on each subject at baseline,on days 1 and 7 of MFGPCL daily *** was assessed in four quadrants using a spectraldomain optical coherence ***:AL was shortened by-26±44μm with lens C,-18±27μm with lens D,-13±29μm with lens A,and-8±30μm with lens B(all P<0.05).A significant overall increase in ChT was observed with all 4 designs(lens A:+6±6μm,B:+3±7μm,C:+8±7μm,and D:+8±7μm).Temporal and superior choroid exhibited more choroidal thickening associated with *** designs induced significant relative peripheral myopia(RPM)beyond the central 20o across the horizontal meridian in both nasal and temporal fields(P<0.05).CONCLUSION:MFGPCLs show a significant influence on ChT and AL,which are associated with significant increase in RPM after short-term *** reliability and feasibility of quantifying short-term changes in ChT support its use as a promising marker for the long-term efficacy of myopia-controlling treatments.

关键词： choroid gas-permeable contact lens retinal defocus axial length myopia

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COVID-19 patient experiences in prehospital pathways:a processual approach using life-events calendar method and state sequence analysis shows detrimental delays

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Family Medicine and Community Health 2024年第1期12卷 45-56页

作者： Romain Lutaud Sebastien Cortaredona Lea Delorme patrick Peretti-watel Juliette Mirouse Manon Borg Lucie Cattaneo Didier Thery Gaetan Gentile Christian Pradier Touitou Irit Philippe Brouqui Sophie Tardieu Michel Carles stéphanie Gentile Department of General Practice Aix-Marseille UniversityMarseilleFrance ADES MarseilleFrance Institut de Recherche pour le Développement(IRD) MarseilleFrance Assistance Publique-Hôpitaux de Marseille(AP-HM) MarseilleFrance INSERM MarseilleFrance Department of Public Health Archet University HospitalNiceFrance MEPHI MarseilleFrance CEReSS-Health Service Research and Quality of life Center MarseilleFrance Department of Infectious Diseases Centre Hospitalier Universitaire de NiceNiceFrance

Objectives To our best knowledge,no study in France has comprehensively investigated the prehospital history of patients admitted for severe cases of COVID-19.‘Patients’voice is an excellent means to capture data on primary care *** aimed to identify clusters of COVID-19 hospitalised patients with similar prehospital symptom sequences,and to test whether these clusters were associated with a higher risk of poor clinical *** Cross-sectional online survey using life-event *** All patients hospitalised for COVID-19 between September 2020 and May 2021 in the Infectious Disease Departments in Nice and in Marseilles in *** 312 patients responded to the *** outcome measures From the day of symptom onset to the day of hospitalisation,we defined a symptom sequence as the time-ordered vector of the successive symptom grades(grade 1,grade 2,grade 3).state sequence analysis with optimal matching was used to identify clusters of patients with similar symptom *** logistic regressions were performed to test whether these clusters were associated with admission to intensive care unit(ICU)and COVID-19 sequelae after *** Three clusters of symptom sequences were identified among 312 complete prehospital pathways.A specific group of patients(29%)experienced extended symptoms of severe COVID-19,persisting for an average duration of 7.5 days before *** group had a significantly higher probability of being admitted to ICU(adjusted OR 2.01).They were less likely to know a loved one who was a healthcare worker,and more likely to have a lower level of ***,this group of patients,who were more likely to have previously visited the emergency room without exhibiting severe symptoms at that time,may have been inclined to postpone reassessment when their health *** relatives played a decisive role in their *** and relevance This study h

关键词： admitted likely life

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