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Multivariate Approach to Characterizing Soil Quality of Gabonese’s Ferralitic Soils

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Open journal of Soil Science 2024年第4期14卷 237-268页

作者： Neil-Yohan Musadji Rolf Gaël Mabicka Obame Michel Mbina Mounguengui Jean aubin Ondo lydie-Stella Koutika Eric Ravire Claude Geffroy laboratoire De Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement Des Sciences Fondamentales De L&#8217Ing&#233nieur Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Institut De Chimie Des Milieux et Maté riaux De Poitiers (IC2MP) Universit&#233 De Poitiers Poitiers France laboratoire De Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement De Phytotechnologie Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Dé partement De G&#233ologie Facult&#233 Des Sciences Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon laboratoire Pluridisciplinaire Des Sciences Ecole Normale Sup&#233rieure Libreville Gabon Centre De Recherche Sur la Productivité et La Durabilit&#233 Des Plantations Industrielles Pointe Noire Republic of Congo Sucaf Gabon Somdiaa Franceville Gabon

Assessing soil quality is essential for crop management and soil temporal changes. The present study aims to evaluate soil quality in the Ferralitic soils context countrywide. This assessment was done using multivariate soil quality indice (SQI) models, such as additive quality index (AQI), weighted quality indexes (WQIadd and WQIcom) and Nemoro quality index (NQI), applied to two approaches of indicator selection: total data set (TDS) and minimum data set (MDS). Physical and chemical soil indicators were extracted from the ORSTOM’s reports resulting from a sampling campaign in different provinces of Gabon. The TDS approach shows soil quality status according to eleven soil indicators extracted from the analysis of 1,059 samples from arable soil layer (0 - 30 cm depth). The results indicated that 87% of all provinces presented a very low soil quality (Q5) whatever the model. Among soil indicators, exchangeable K+ and Mg2+, bulk density and C/N ratio were retained in MDS, using principal component analysis (PCA). In the MDS approach, 50 to 63% of provinces had low soil quality grades with AQI, WQIadd and NQI, whereas the total was observed with WQIcom. Only 25% of provinces had medium soil quality grades with AQI and NQI models, while 12.5% (NQI) and 25% (AQI) presented high quality grades. Robust statistical analyses confirmed the accuracy and validation (0.80 r P ≤ 0.016) of AQI, WQIadd and NQI into the TDS and MDS approaches. The same sensitivity index value (1.53) was obtained with AQI and WQIadd. However, WQIadd was chosen as the best SQI model, according to its high linear regression value (R2 = 0.82) between TDS and MDS. This study has important implications in decision-making on monitoring, evaluation and sustainable management of Gabonese soils in a pedoclimatic context unfavorable to plant growth.

关键词： Gabon Ferralitic Soil Soil Indicators Standard Score Function Soil Quality Indices Sustainable Soil Soil Management

National Soil Organic Carbon Stocks Inventories under Different Mangrove Forest Types in Gabon

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Open journal of Forestry 2024年第2期14卷 127-140页

作者： Rolf Gaël Mabicka Obame Neil-Yohan Musadji Jean Hervé Mve Beh lydie-Stella Koutika Jean aubin Ondo Farrel Nzigou Boucka Michel Mbina Mounguengui Claude Geffroy Dé partement de Phytotechnologie Institut National d&#8217Agronomie et de Biotechnologies Universit&#233 des Sciences et Techniques de Masuku Franceville Gabon Dé partement des Sciences Fondamentales de l&#8217Ing&#233nieur Institut National d&#8217Agronomie et de Biotechnologies Universit&#233 des Sciences et Techniques de Masuku Franceville Gabon Institut Agronomiques et Forestiè res Centre National des Recherches Scientifiques et Technologiques Libreville Gabon Research Centre on the Durability and the Productivity of Industrial Plantations (CRDPI) Pointe Noire Republic of Congo laboratoire Pluridisciplinaire des Sciences &#201cole Normale Sup&#233rieure Libreville Gabon Agence Gabonaise d’ &#201tude et d&#8217Observation Spatiale Immeuble les Arcades Libreville Gabon Dé partement de G&#233ologie Faculte des Sciences Universit&#233 des Sciences et Techniques de Masuku Franceville Gabon Institut de Chimie des Milieux et Maté riaux de Poitiers (IC2MP) Universit&#233 de Poitiers Poitiers France

Gabonese’s estuary is an important coastal mangrove setting and soil plays a key role in mangrove carbon storage in mangrove forests. However, the spatial variation in soil organic carbon (SOC) storage remain unclear. To address this gap, determining the SOC spatial variation in Gabonese’s estuarine is essential for better understanding the global carbon cycle. The present study compared soil organic carbon between northern and southern sites in different mangrove forest, Rhizophora racemosa and Avicennia germinans. The results showed that the mean SOC stocks at 1 m depth were 256.28 ± 127.29 MgC ha−1. Among the different regions, SOC in northern zone was significantly (p p layers contained higher SOC stocks (254.62 ± 128.09 MgC ha−1) than upper layers (55.42 ± 25.37 MgC ha−1). The study highlights that low deforestation rate have led to less CO2 (705.3 Mg CO2e ha−1 - 922.62 Mg CO2e ha−1) emissions than most sediment carbon-rich mangroves in the world. These results highlight the influence of soil texture and mangrove forest types on the mangrove SOC stocks. The first national comparison of soil organic carbon stocks between mangroves and upland tropical forests indicated SOC stocks were two times more in mangroves soils (51.21 ± 45.00 MgC ha−1) than primary (20.33 ± 12.7 MgC ha−1), savanna and cropland (21.71 ± 15.10 MgC ha−1). We find that mangroves in this study emit lower dioxide-carbon equivalent emissions. This study highlights the importance of national inventories of soil organic carbon and can be used as a baseline on the role of mangroves in carbon sequestration and climate change mitigation but the variation in SOC stocks indicates the need for further national data.

关键词： Mangroves Forest Soil Organic Carbon Stocks Rizophora Racemose Avicenia germinans Gabon

High-speed silicon photonic electro-optic Kerr modulation

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Photonics Research 2024年第1期12卷 51-60页

作者： joNATHAN PElTIER WEIWEI ZHANG lEOPOlD VIROT CHRISTIAN lAFFORGUE lUCAS DENIEl DElPHINE MARRIS-MORINI GUY aubin FARAH AMAR DENH TRAN XINGZHAO YAN CAllUM G.lITTlEjoHNS CARlOS AlONSO-RAMOS KE lI DAVID J.THOMSON GRAHAM REED lAURENT VIVIEN University Paris-Saclay CNRSCentre for Nanoscience and Nanotechnology(C2N)Palaiseau 91120France University Grenoble Alpes CEALETIGrenoble 38000France Optoelectronics Research Centre Zepler Institute for Photonics and NanoelectronicsFaculty of Engineering and Physical SciencesUniversity of SouthamptonSouthampton SO171BJUK

Silicon-based electro-optic modulators contribute to easing the integration of high-speed and low-power consumption circuits for classical optical communications and data *** the plasma dispersion modulation,an alternative solution in silicon is to exploit the DC Kerr effect,which generates an equivalent linear electro-optical effect enabled by applying a large DC electric *** some theoretical and experimental studies have shown its existence in silicon,limited contributions relative to plasma dispersion have been achieved in high-speed modulation so *** paper presents high-speed optical modulation based on the DC Kerr effect in silicon PIN *** contributions of both plasma dispersion and Kerr effects have been analyzed in different waveguide configurations,and we demonstrated that the Kerr induced modulation is dominant when a high external DC electric field is applied in PIN ***-speed optical modulation response is analyzed,and eye diagrams up to 80 Gbit/s in NRZ format are obtained under a *** of 30 *** work paves the way to exploit the Kerr effect to generate high-speed Pockels-like optical modulation.

关键词： waveguide dispersion effect

The value does not exist!A motivation for extremal analysis

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Probability, Uncertainty and Quantitative Risk 2022年第3期7卷 195-214页

作者： Jean-Pierre aubin Hélène Frankowska Retired 14Rue Domat75005 ParisFrance CNRS IMJ-PRGSorbonne Université4Place Jussieu75252 ParisFrance

Standard mathematical economics studies the production,exchange,and consumption of goods“provided with units of measurement,”as in physics,in order to be enumerated,quantified,added,***,“baskets of goods,”which should describe subsets of goods,are mathematically represented as commodity vectors of a vector space,linear combination of units of goods,evaluated by prices,which are linear numerical ***,in this sense,mathematical economics is a branch of ***,economics,and many other domains of life sciences,investigate also what will be called entities,defining elements deprived of units of measure,which thus cannot be enumerated.(1)Denoting by X the set of entities x∈X deprived of units of measurement,a“basket of goods”is actually a subset K■X of the set entities,i.e.,an element of the“hyperset”P(X),the family of subsets of X,and no longer a commodity vector of the vector space of commodities;(2)Entities can be“gathered”instead of being“added”;(3)Entities can still be evaluated by a family of functions A:x 2 X 7!A(x)2 Rregarded as a“valuators,”in lieu and place of linear“prices”evaluating the units of economic goods.(4)Subsets of entities can be evaluated by an“interval of values”between two extremal ones,the minimum and the maximum,instead of the sum of values of units of goods weighted by their *** sciences dealing with intertwined relations among many combinations of entities,hypersets offer metaphors of“lamarckian complexity”that keeps us away from binary relations,graphs of functions,and set-valued maps,to focus our attention on“multinary relations”between families of *** deprived of units of measurement,these“proletarian”entities still enjoy enough properties for this pauperization to be mathematically *** is the object of this extremal manifesto:in economics and other domains of life sciences,vector spaces should yield their imperial status of“state space”to hypersets and linear prices to hy

关键词： Valuators Extremal topologies Transfer of topologies Confined sets Extremal evolution Inert relation Viability kernel Regulator

A test of the coupling of predator defense morphology and behavior variation in two threespine stickleback populations

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Current Zoology 2012年第1期58卷 53-65页

作者： lacasse, Jennyfer aubin-Horth, Nadia Département de Biologie & Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval. Québec QC Canada. G1V 0A6

Among-population differences in morphology and behaviors such as boldness have been shown to co-vary with eco- logical conditions, including predation regime. However, between- and within-population covariation of predator defense mor- phology with variation in behaviors relevant to ecology and evolution （boldness, exploration, activity, sociability and aggressive- ness, often defined as personality traits when they are consistent across time and contexts） have never been quantified together in a single study in juvenile fish from populations found in contrasting environments. We measured predator defense morphology differences between adults from two freshwater populations of threespine sticklebacks with different ecological conditions. We then quantified five behaviors in juveniles from both populations raised in a common environment. Wild-caught adults showed significant differences in predator defense morphology. One population had significantly lower lateral plate number, shorter dorsal spine, pelvic spine and pelvic girdle. Furthermore, 61% of individuals from that population showed an absence of pelvic spine and girdle. At the population level, we found that differences in defense morphology in adults between the two lakes were coupled with differences in behaviors in juveniles raised in a common environment. levels of activity, aggressiveness and boldness were higher in juveniles from the population lacking predator defense structures. At the individual level, anti-predator morphology of adult females could not predict their offspring＇s behavior, but juvenile coloration predicted individual boldness in a popula- tion-specific manner. Our results suggest that ecological conditions, as reflected in adult predator defense morphology, also affect juvenile behavior in threespine sticklebacks, resulting in trait co-specialization, and that there is a genetic or epigenetic compo- nent to these behavioral differences [Current Zoology 58 （1）： 53-65, 2012].

关键词： Behaviors Personality Predator defense morphology Coloration Juvenile Threespine stickleback Common rear- ing environment

Identification of major sources controlling groundwater geochemistry in Mount Makabaï in the Far-North of Cameroon(the northernmost part of the Pan-African Belt)

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Acta Geochimica 2023年第2期42卷 266-289页

作者： Merlin GountiéDedzo DésiréTsozué Amidou Kpoumié aubin Nzeugang Nzeukou Department of life and Earth Sciences Higher Teachers’Training CollegeUniversity of MarouaP.O.Box.55MarouaCameroon Department of Earth Sciences Faculty of ScienceUniversity of MarouaP.O.Box.814MarouaCameroon

The present work focuses on the volcanic basement rock geochemistry of Mount Makabaï(MarouaCameroon city)in relation to groundwater *** were centered on an approach involving an association of several methods such as geological cartography,hydrogeology,and *** rock samples,four disturbed soil samples,three undisturbed soil samples,and 20 samples of groundwater in 10 wells were collected during fieldwork and prepared for laboratory *** exhibit porphyritic,aphyric,and subaphiric *** phenocryst phases are mainly olivine,clinopyroxene,and *** on whole rock major element chemical compositions,the Makabaï samples,plotted on Na_(2)O+K_(2)O versus SiO_(2)diagram,are mugearite,hawaiite,and *** ratio of(MgO+CaO)/(Na_(2)O+K_(2)O)exceeds unity and shows dominance of alkaline Earth metals(MgO:2.99-4.48%;CaO:6.19-9.80%)relatively to alkali metals(Na_(2)O:2.27-4.46%;K_(2)O:2.09-2.51%).Exchangeable base contents are high,mostly represented by Ca and Mg,whose contents vary from 14.6 to 35.28 cmol(+)kg^(-1)and from 3.28 to9.48 cmol(+)kg^(-1)*** CECclayis likewise high,fluctuating between 116.80 and181.38 cmol(+)kg^(-1),values in line with the presence of 2:1 clay minerals represented in the study area by *** the water samples,the Ca2+and Na+contents are generally higher than K^(+)and Mg^(2+),reflecting the relative abundance of Na_(2)O and CaO oxides to K_(2)O and MgO oxides in rocks where different waters were *** waters of Makabaï are acidic to neutral(6.3≤pH≤7.4)and weakly to highly mineralized(110.0≤EC≤1190.0μS/cm).Hydro-geochemical classification by using the Piper diagram revealed two water types:(1)CaMg-HCO_(3)(40%)and(2)CaMg-Cl or CaMg-SO4(60%).The average content of ions in all the analyzed samples was HCO_(3)^(-)>>NO_(3)^(-)>SO_(4)^(2-)>Cl-for anions and Ca^(2+)>>Mg^(2+)>Na^(+)>K^(+)for *** mechanisms governing ionic constituents of groundwater in

关键词： Mount Makabaï-Maroua city Far-North Cameroon Bedrock minerals Groundwater-rock-soil interaction Crystalline basement

A pediatric robotic thumb exoskeleton for at-home rehabilitation The isolated orthosis for thumb actuation(IOTA)

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International journal of Intelligent Computing and Cybernetics 2014年第3期7卷 233-252页

作者： Patrick aubin Kelsey Petersen Hani Sallum Conor Walsh Annette Correia leia Stirling Rehabilitation and Development Center of Excellence for limb loss Prevention and Prosthetic Engineering VA Puget Sound Health Care SystemSeattleWashingtonUSA Wyss Institute for Biologically Inspired Engineering Harvard UniversityBostonMassachusettsUSA Boston Children’s Hospital BostonMassachusettsUSA Wyss Institute for Biologically Inspired Engineering Harvard UniversityBostonMassachusettsUSA and Massachusetts Institute of TechnologyCambridgeMassachusettsUSA

Purpose–Pediatric disorders,such as cerebral palsy and stroke,can result in thumb-in-palm deformity greatly limiting hand *** not only limits children’s ability to perform activities of daily living but also limits important motor skill ***,the isolated orthosis for thumb actuation(IOTA)is 2 degrees of freedom(DOF)thumb exoskeleton that can actuate the carpometacarpal(CMC)and metacarpophalangeal(MCP)joints through ranges of motion required for activities of daily *** paper aims to discuss these ***/methodology/approach–IOTA consists of a lightweight hand-mounted mechanism that can be secured and aligned to individual *** mechanism is actuated via flexible cables that connect to a portable control *** encoders and bend sensors monitor the 2 DOF of the thumb and flexion/extension of the wrist.A linear force characterization was performed to test the mechanical efficiency of the cable-drive transmission and the output torque at the exoskeletal CMC and MCP joints was ***–Using this platform,a number of control modes can be implemented that will enable the device to be controlled by a patient to assist with opposition grasp and fine motor *** force and torque studies showed a maximum efficiency of 44 percent,resulting in a torque of 2.3971.06 in.-lbf and 0.6970.31 in.-lbf at the CMC and MCP joints,*** implications–The authors envision this at-home device augmenting the current in-clinic and at-home therapy,enabling telerehabilitation ***/value–This paper presents the design and characterization of a novel device specifically designed for pediatric grasp telerehabilitation to facilitate improved functionality and somatosensory learning。

关键词： Pediatric Exoskeleton At-home hand rehabilitation Rehabilitation robotics Thumb

Diesel engine exhaust exposures in two underground mines

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International journal of Mining Science and Technology 2017年第4期27卷 641-645页

作者： Debia Maximilien Couture Caroline Njanga Pierre-Eric Neesham-Grenon Eve lachapelle Guillaume Coulombe Hugo Hallé Stéphane aubin Simon Department of Environmental and Occupational Health School of Public Health Universite de Montreal 2375 chemin de la Cote Ste-Catherine Montreal H3T IA8 Canada Department of Mechanical Engineering F.cole de Technologie Superieure 1100 rue Notre-Dame Ouest Montreal H3C 1K3 Canada Health and Safety Agnico Eagie Mines 145 King Street East Suite 400 Toronto MSC 2Y7 Canada Health and Safety Westwood Mine (IAMGOLD) Chemin Arthur Doyon PreissacJOY 2EO Canada Institut de recherche Robert-Sauve en sante et en securite du travail (IRSST) 505 Boul. de Maisonneuve Ouest Montreal H3A 3C2 Canada

Exposure to diesel engine exhaust(DE) is a major concern in underground mines. It has been linked to cardiopulmonary diseases and is classified as a human carcinogen. The goal of this study is to assess DE exposures in workers at two underground gold mines, to compare exposure levels within and between the mines, and to compare different methods of measuring DE exposures, namely respirable combustible dust(RCD), elemental carbon(EC) and total carbon(TC). Ambient and personal breathing zone(PBZ) measurements were taken. Side-by-side monitoring of RCD and of the respirable fraction of EC and TC(EC_Rand TC_R) was carried out in the workers' breathing zone during full-shift *** ambient measurements, in addition to EC_R, TC_Rand RCD, a submicron aerosol fraction(less than 1 mm) of EC and TC was also sampled(EC_1and TC_1). Average ambient results of 240 mg/m^3 in RCD, 150 mg/m^3 in EC_Rand 210 mg/m^3 in TC_Rare obtained. Average PBZ results of 190 mg/m^3 in RCD,84 mg/m^3 in EC3Rand 150 mg/min TC_Rare obtained. Very good correlation is found between EC_Rand EC_1 with a Pearson correlation coefficient of 0.99(p lculated between the two logtransformed concentrations. No differences are reported between EC_Rand EC_1, nor between TC_Rand TC_1, since ratios are equal to 1.04, close to 1, in both cases. Highest exposures are reported for loadhaul-dump(lHD) and jumbo drill operators and conventional miners. Significant exposure differences are reported between mines for truck and lHD operators(p lts, and 1.3 for ambient results. The variability observed in the TC_R/EC_Rratio shows that interferences from non-diesel related organic carbon can skew the interpretation of results when relying only on TC data.

关键词： Diesel exposure Underground mine Respirable combustible dust Elemental carbon Total carbon Diesel particulate matter Similar exposure groups

Recent advances in development of vertical-cavity based short pulse source at 1.55 μm

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Frontiers of Optoelectronics 2014年第1期7卷 1-19页

作者： Zhuang ZHAO Sophie BOUCHOUlE Jean-Christophe HARMAND Gilles PATRIARCHE Guy aubin Jean-louis OUDAR laboratoire de Photonique et de Nanostructures (lPN) CNRS Marcoussis France

This paper reviews and discusses recent developments in passively mode-locked vertical external cavity surface emitting lasers （Ml-VECSEls） for short pulse generation at 1.55 gin. After comparing Ml- VECSEls to other options for short pulse generation, we reviewed the results of Ml-VECSEls operating at telecommunication wavelength and point out the chal- lenges in achieving sub-picosecond operation from a Ml- VECSEl at 1.55 gm. We described our recent work in the VECSEls and semiconductor saturable absorber mirrors （SESAMs）, their structure design, optimization and characterization, with the goal of moving the pulse width from picosecond to sub-picosecond.

关键词： semiconductor laser vertical external cavitysurface emitting laser (VECSEl) indium phosphide heatdissipation saturable absorber mirror mode-locking