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Variations in Soil Organic Matter Content in Cultivated and Uncultivated Calcareous Soils from the Mediterranean Island of Malta after 15 Years of Cultivation

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Open Journal of Soil Science 2024年第4期14卷 210-226页

作者： Anthony T. Sacco Marcelle Agius Clara Didier Institute of Earth Systems Division of Rural Sciences and Food Systems University of Malta Msida Malta É cole Nationale Sup&#233rieure Agronomique de Toulouse Auzeville-Tolosane France

The soils of Malta are calcareous and generally undeveloped. Organic matter (OM) in these soils is low and farmers are constantly urged to increase it. The objective of this study was to evaluate any temporal variation in soil OM after 15 years of cultivation, and determine whether soil series, soil depth, and cultivation influence variation. OM was determined in the topsoil and subsoil of 7 agricultural and 4 non-agricultural sites. The sites represented 7 different soil series that are present on the island. In sampling periods 1 (t = 0 years) and 2 (t =15 years), the OM content in the collective (all soil series) bulk (topsoil and subsoil) uncultivated soil was 3.9 % and 3.8 % respectively. This was significantly greater than that of the collective bulk cultivated soil (2.4% and 2.3%). The OM in the collective uncultivated topsoil was 5.4% and 5.2% in periods 1 and 2 and was significantly higher than that of the cultivated topsoil (2.5% in both periods). The OM content in the collective uncultivated subsoil was 2.3% and 2.5% in periods 1 and 2 respectively but only that measured in period 2 was significantly higher than that of the cultivated subsoil (2.2% in both periods). On an individual soil series basis, the OM in the uncultivated topsoils was significantly higher than that of their cultivated counterparts. The differences in the subsoils were not significant. Across the uncultivated soil series, OM was significantly higher in the topsoil than in the subsoil but in the cultivated soil series the differences between topsoil and subsoil were not significant. There was no significant difference in OM between the uncultivated soils of different series, but in the cultivated the OM content was higher in soils that were more mature. After 15 years, no significant change in OM occurred in both the collective cultivated and uncultivated bulk soils, the collective topsoil and subsoil, and in most of the individual series. The OM content of each soil series was also s

关键词： Soil Organic Carbon Agricultural Land Non-Agricultural Land Land Management

Gifted Students’Special Educational Programs in France:An Analysis of Students’Needs as Perceived by Headmasters-A Secondary Publication

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Journal of Contemporary Educational Research 2024年第4期8卷 316-327页

作者： Karine Buard Minna Puustinen Amélie Courtinat-Camps Research Group on Disability AccessibilityEducational and School Practices(GRHAPES)INSHEAFrance Developmental and Educational Psychology “Psychology of Socialisation-Development and Work”Laboratory(LPS-DT)Toulouse Jean Jaurès UniversityFrance

Some French public middle schools offer gifted students the opportunity to pursue their education in general classes,while benefiting from specific facilities within the framework of a dedicated educational *** this study,we sought to identify and analyze the needs of these students as perceived by the headmaster of each middle school *** results highlight two main student needs,common to all these programs(uneasiness and difficulties in peer relationships)as well as needs specifically mentioned by some headmasters(non-adaptive behavior).

关键词： Learning difficulties Students in difficulty Education policies

Ar^+/Ar, O_2^+/O_2 and N_2^+/N_2 Elastic Momentum Collision Cross Sections: Calculation and Validation Using the Semi-Classical Model

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Plasma Science and Technology 2014年第6期16卷 588-592页

作者： Djilali BENYOUCEF Mohammed YOUSFI Laboratoire Génie Electrique et Energies Renouvelables Chlef University universitéde toulouse LAPLACE UMR CNRS

The aim of this paper is to obtain relevant sets of collision cross sections of the parent ions in low pressure discharges in argon, oxygen, and nitrogen, i.e., Ar＋ in Ar, O2＋ in O2 and N2＋ in N2. These ion data are first discussed and then validated from comparisons between the calculated transport coefficients and those measured in the literature. The elastic momentum transfer collision cross sections are determined from a semi-classical approximation for the phase shift calculation based on a 12-6-4 inter-particle potential while ion transport coefficients are determined versus the reduced electric field from Monte Carlo simulations.

关键词： inter-particle interaction potentials phase shift JWKB (Jeffreys WentzelKramers Brillouin) momentum collision cross sections Monte Carlo simulation ion trans-port coefficient

Characterization and photoluminescence properties of ultrafine copper molybdate(α-CuMoO_4) powders prepared via a combustion-like process

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International Journal of Minerals,Metallurgy and Materials 2016年第11期23卷 1340-1345页

作者： Mohamed Benchikhi Rachida El Ouatib Sophie Guillemet-Fritsch Lahcen Er-Rakho Bernard Durand Laboratoire de Physico-Chimie des Matériaux Inorganiques Faculté des Sciences Ain Chock Université Hassan Ⅱ Casablanca Institut Carnot CIRIMAT CNRS Université de Toulouse

We report a simple method for preparing copper（II） molybdate（CuMoO_4） powders via a combustion-like process. A gel was first prepared by the polymerizable complex method, where citric acid was used as a complexing and polymerizing agent and nitric acid was used as an oxidizing agent. The thermal decomposition behavior of the（CuMo）-precursor gel was studied by thermogravimetry–differential thermal analysis（TG–DTA）, Fourier transform infrared spectroscopy（FTIR）, and X-ray diffraction（XRD）. We observed that the crystallization of CuMoO_4 powder was completed at 450°C. The obtained homogeneous powder was composed of grains with sizes in the range from 150 to 500 nm and exhibited a specific surface area of approximately 5 m^2/g. The average grain size increased with increasing annealing temperature. The as-prepared CuMoO_4 crystals showed a strong green photoluminescence emission at room temperature under excitation at 290 nm, which we mainly interpreted on the basis of the Jahn-Teller effect on [MoO_4^（2-）] complex anions. We also observed that the photoluminescence intensity increased with increasing crystallite size.

关键词： copper molybdate chemical synthesis photoluminescence Jahn-Teller effect

Larval interference competition between the native Neotropical mosquito Limatus durhamii and the invasive Aedes aegypti improves the fitness of both species

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Insect Science 2018年第6期25卷 1102-1107页

作者： Stanislas Talaga Alain Dejean Clémence Mouza Yves Dumont Céline Leroy lnsUtut Pasteur de la Guyane Unitéd'Entomologie MédicaleCayenne cedexFrance CNRS UMR EcoFoGAgroParisTechCiradINRAUniversitédes AntillesUniversitéde GuyaneKourouFrance CNRS INPTUPSEcolabUniversitéde ToulouseToulouseFrance AMAP CIRADCNRSINRAIRDUniversit6MontpellierMontpellierFrance

Interspecific competition with native species during biological invasions can sometimes limit alien *** aimed to determine the potential ecological effects of Limatus durhamii Theobald 1901,a native Neotropical mosquito (Diptera:Culicidae) species,on the invasive species Aedes (Stegomyia)aegypti (Linnaeus 1762)that breeds in the same artificial water *** time and adult dry mass were measured in 3 rearing conditions:control (a single larva),intraspecific competition (2 conspecific larvae),and interspecific competition (2 heterospecific larvae).Food was provided ad libitum to eliminate exploitative *** ***,development time was not affected by interspecific interference competition (nonsignificant differences with the control)and the adult dry mass was significantly higher,meaning that individual fitness likely ***,because previous studies showed longer development time and lighter adults during competition with other invasive mosquitoes,it is likely that *** can express a different phenotype depending on the competing *** similar pattern found for *** females and the nonsignificant difference with the control for males explain in part why this species can compete with ***.

关键词： Aedes aegypti increased fitness interference competition Limatus durhamii phenotypic plasticity resistance to invasion

MicroRNAs as emerging biomarkers and therapeutic targets for pancreatic cancer

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World Journal of Gastroenterology 2014年第32期20卷 11199-11209页

作者： Marion Gayral Sébastien Jo Naima Hanoun Alix Vignolle-Vidoni Hubert Lulka Yannick Delpu Aline Meulle Marlène Dufresne Marine Humeau Maёl Chalret du Rieu Barbara Bournet Janick Sèlves Rosine Guimbaud Nicolas Carrère Louis Buscail Jérome Torrisani Pierre Cordelier Cancer Research Center of toulouse Team 10 UMR INSERM U1037Université Paul Sabatier P?le Digestif Centre Hospitalier Universitaire Toulouse

Despite tremendous efforts from scientists and clinicians worldwide, pancreatic adenocarcinoma(PDAC) remains a deadly disease due to the lack of early diagnostic tools and reliable therapeutic approaches. Consequently, a majority of patients(80%) display an advanced disease that results in a low resection rate leading to an overall median survival of less than 6 months. Accordingly, robust markers for the early diagnosis and prognosis of pancreatic cancer, or markers indicative of survival and/or metastatic disease are des-perately needed to help alleviate the dismal prognosis of this cancer. In addition, the discovery of new therapeutic targets is mandatory to design effective treatments. In this review, we will highlight the translational studies demonstrating that microRNAs may soon translate into clinical applications as long-awaited screening tools and therapeutic targets for PDAC.

关键词： MicroRNAs Biomarkers Pancreatic cancer Therapeutic targets Precancerous lesions

Spin Dynamics in (111) GaAs/AlGaAs Undoped Asymmetric Quantum Wells

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Chinese Physics Letters 2012年第9期29卷 159-161页

作者： WANG Gang YE Hui-Qi SHI Zhen-Wu WANG Wen-Xin MARIE Xavier BALOCCHI Andrea AMAND Thierry LIU Bao-Li Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190 universitéde toulouse INSA-CNRS-UPSLPCNO135 avenue de Rangueil31077 ToulouseFrance

The electron spin dynamics is investigated by the time-resolved Kerr rotation technique in a pair of special GaAs/AlGaAs asymmetric quantum well samples grown on(111)-oriented substrates,whose structures are the same except for their opposite directions of potential asymmetry.A large difference of spin lifetimes between the two samples is observed at low *** difference is interpreted in terms of a cancellation effect between the Dresselhaus spin-splitting term in the conduction band and another term induced by interface inversion *** deviation decreases with the increasing temperature,and almost disappears when T>100 K because the cubic Dresselhaus term becomes more important.

关键词： Quantum conduction directions

Rapid prototyping of a polymer MEMS dropletdispenser by laser-assisted 3D printing

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Microsystems & Nanoengineering 2023年第4期9卷 211-221页

作者： Rémi Courson Oleksii Bratash Ali Maziz CloéDesmet Ricardo Alvarado Meza Loïc Leroy Elodie Engel Arnaud Buhot Laurent Malaquin Thierry Leïchlé LAAS-CNRS Universitéde ToulouseCNRS31400 ToulouseFrance universitéGrenoble Alpes CNRSCEAIRIGSyMMES38000 GrenobleFrance Georgia Tech−CNRS International Research Laboratory AtlantaGA 30332USA

In this work, we introduce a polymer version of a previously developed silicon MEMS drop deposition tool for surfacefunctionalization that consists of a microcantilever integrating an open fluidic channel and a reservoir. The device isfabricated by laser stereolithography, which offers the advantages of low-cost and fast prototyping. Additionally,thanks to the ability to process multiple materials, a magnetic base is incorporated into the cantilever for convenienthandling and attachment to the holder of a robotized stage used for spotting. Droplets with diameters ranging from∼50 μm to ∼300 μm are printed upon direct contact of the cantilever tip with the surface to pattern. Liquid loading isachieved by fully immersing the cantilever into a reservoir drop, where a single load results in the deposition of morethan 200 droplets. The influences of the size and shape of the cantilever tip and the reservoir on the printing outcomeare studied. As a proof-of-concept of the biofunctionalization capability of this 3D printed droplet dispenser,microarrays of oligonucleotides and antibodies displaying high specificity and no cross-contamination are fabricated,and droplets are deposited at the tip of an optical fiber bundle.

关键词： cantilever reservoir printing

S1P: the elixir of life for naive T cells

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Cellular & Molecular Immunology 2018年第7期15卷 657-659页

作者： Michaël Pérès Anne Montfort Nathalie Andrieu-Abadie Céline Colacios Bruno Ségui INSERM UMR1037 Centre de Recherches en Cancérologie de ToulouseToulouse 31037France Facultéde pharmacie UniversitéToulouse III Paul-SabatierToulouse 31062France Laboratoire d’hématologie CHU de ToulouseToulouse 31059France Equipe Labellisée Ligue Contre Le Cancer Toulouse 31037France Correspondence:Professor B SéguiPhDINSERMUMR1037 CRCTCentre de Recherches en Cancérologie de Toulouse2 avenue Hubert CurienToulouse 31037France

During their life,T cells are constantly circulating throughout the ***-1-phosphate(S1P),a sphingolipid metabolite,triggers T cell egress from the thymus and secondary lymphoid organs(SLO)into the lymph and the *** phenomenon is dependent on the S1P gradient between lymphoid organs(including thymus and SLO)and the lymphatic and blood vessels,which exhibit low,intermediate and high S1P levels,respectively.T cells follow the S1P gradient via the engagement of the G-protein-coupled receptor S1P receptor 1(S1P1)expressed on T cells.1 S1P production is regulated by various sphingolipid-metabolizing *** sphingosine kinases 1 and 2(SKs),encoded by Sphk1 and Sphk2,phosphorylate the sphingosine(Sph)into ***,S1P can be dephosphorylated to Sph by S1P phosphatases 1 and 2,encoded by Sgpp1 and ***,S1P can be irreversibly degraded by the S1P Lyase(SPL),encoded by Sgpl1,into phosphoethanolamine and hexadecenal.

关键词： organs al. lymphoid