148 results on '"Lakhloufi A"'
Search Results
2. Detection of Potentially Ore-Bearing Hydrothermal Alteration Zones in the Rehamna Massif (Morocco)
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Mohamed El Mimouni, Abdellatif Aarab, Abdellah Lakhloufi, Abderrazak Hamzaoui, Ayoub Aabi, and Kawtar Benyas
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rehamna massif ,remote sensing ,aster data ,band ratios ,hydrothermal alteration ,potential sites ,Ecology ,QH540-549.5 - Abstract
This study aims to map minerals of hydrothermal alteration zones in the Rehamna Massif, formerly site of large exploitation of Pb-Zn, Ba-Pb and W-Sn hosted within the Paleozoic basement, using the advantages of remote sensing technique. In this regard, ASTER remote sensing data have been used as a substrate for spectral processing, namely band ratios, to identify hydrothermal alteration zones characteristic of polymetallic mineralization. Band ratio technique leads us to map the Phyllic, Argillic, Prophylitic, Oxidation and kaolinite zones. Other ratios such as Muscovite, Allunite, Calcite and Fe-oxides were also computed. The areas reported were locally compared with the geological setting. The compilations of the results facilitate the identification of eight potential sites suitable for a possible tactical research phase. These results can encourage mining exploration and guide mining companies to the most potentially ore-bearing sites and support the economic development of the Rehamna area.
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- 2024
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3. Contribution of multispectral remote sensing to mining exploration in the Rehamna Massif, Moroccan Meseta
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El-Mimouni Mohamed, Aarab Abdellatif, Lakhloufi Abdellah, Hamzaoui Abderrazak, Akhssas Ahmed, and Benyas Kawtar
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rehamna massif ,mining exploration ,aster image ,field investigation ,Environmental sciences ,GE1-350 - Abstract
The Western Moroccan Meseta contains mining sites in operation for several decades and others in development. The Rehamna Massif belonging to this, is the subject of this study. The present study reveals new results on the mineralization in this massif. It is based on the synergy of field investigation data and ASTER image analysis (L1T) covering this massif. Through spectral processing, namely the calculation of the band ratios, ACP and MNF, applied to the nine VNIR and SWIR bands of this image, it was possible to reveal the distribution of hydrothermal alteration minerals in the study area. The conjuncture of these data allowed us to select geological targets likely to be of potential mining interest in the massif.
- Published
- 2020
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4. Efficient and rapid one-step method to generate gene deletions in Streptococcus pyogenes
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Lionel Schiavolin, Dalila Lakhloufi, Gwenaelle Botquin, Geoffrey Deneubourg, Corentin Bruyns, Jenny Steinmetz, Charlotte Henrot, Valérie Delforge, Pierre R. Smeesters, and Anne Botteaux
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Streptococcus pyogenes ,knockout ,rapid method ,Microbiology ,QR1-502 - Abstract
ABSTRACT Streptococcus pyogenes or Group A Streptococcus (GAS) remains a significant infectious problem around the world, particularly in low- and middle-income settings. Moreover, a recent invasive GAS infection (iGAS) upsurge has been observed in high-income settings. However, to date, no vaccine is available. Finding a good vaccine antigen and understanding the role of virulence factors in GAS infections have been hampered, in part, by technical difficulties to transform the many different strains and generate knockout mutants. Using colE1-type plasmid as a suicide vector, we have set up a method allowing the generation of non-polar mutants of GAS in 3 days.IMPORTANCEGroup A Streptococcus (GAS) is a major human pathogen, causing diseases ranging from mild and superficial infections of the skin and pharyngeal epithelium to severe systemic and invasive diseases. Since June 2022, several European countries, the US, and Australia are facing an upsurge of invasive life-threatening GAS infections. Finding a good vaccine antigen and understanding the role of virulence factors in GAS infections have been hampered, in part, by technical difficulties to transform the many different GAS strains and generate knockout mutants. Moreover, these tools must be adapted to a large range of different strains, since GAS are divided into more than 260 emm-types (M-type). We have set up a method allowing the generation of non-polar mutants of GAS in 3 days and in diverse backgrounds, which contrasts with previously published protocols.
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- 2024
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5. Electrochemical responses and surface degradation analyses alumina and feldspar dental materials in acidic environments: A comprehensive in vitro study
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Soraya Lakhloufi, Najoua Labjar, Houda Labjar, Abdelouahed Dahrouch, and Souad El Hajjaji
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Dental biomaterials ,Electrochemical responses ,Surface degradation ,Alumina ,Feldspar ,Acidic environments ,Clay industries. Ceramics. Glass ,TP785-869 - Abstract
This in vitro study examines the electrochemical responses and surface degradation of alumina and feldspar dental ceramic materials in acidic environments using cyclic polarization and electrochemical impedance spectroscopy (EIS). Alumina and feldspar demonstrate balanced responses in both Fusayama Artificial Saliva and acidic solutions, indicating effective passivation. SEM/EDX analyses after 168-h immersion reveal significant elemental variations, suggesting complex surface phenomena and chemical reactions leading to oxide layer formation. Alumina exhibits increased Si, O, Al, Na, K, and C counts, while feldspar shows increased Si, O, Al, Na with reduced C and Ca levels, indicating complex reactions. Immersion induces notable elemental composition modifications, with alumina showing remarkable corrosion resistance and feldspar undergoing selective dissolution. This study provides insights into the electrochemical and surface degradation of these materials, emphasizing long-term stability and the need for continuous monitoring of protective layer dynamics in future research on corrosion-resistant dental biomaterials.
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- 2024
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6. Electrochemical responses and surface degradation analyses alumina and feldspar dental materials in acidic environments: A comprehensive in vitro study
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Lakhloufi, Soraya, Labjar, Najoua, Labjar, Houda, Dahrouch, Abdelouahed, and El Hajjaji, Souad
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- 2024
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7. Electrochemical behavior and surface stability of dental zirconia ceramics in acidic environments
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Lakhloufi, Soraya, Labjar, Najoua, Labjar, Houda, Serghini- Idrissi, Malika, and El Hajjaji, Souad
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- 2024
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8. THU-331-YI The humoral profile of immunoglobulins specific for microbiota antigens stratifies the severity of patients affected by alcohol-related liver disease and predicts their 90-d mortality
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Putignano, Antonella, primary, Kelkar, Natasha, additional, Thiriard, Anaïs, additional, Sharma, Shilpee, additional, Lakhloufi, Dalila, additional, Botteaux, Anne, additional, Meuree, Samuel, additional, Moreno, Christophe, additional, Jiang, Yiwei, additional, Delphine, Degré, additional, Filee, Patrice, additional, Ackerman, Margaret, additional, Gustot, Thierry, additional, and Marchant, Arnaud, additional
- Published
- 2024
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9. Detection of Potentially Ore-Bearing Hydrothermal Alteration Zones in the Rehamna Massif (Morocco).
- Author
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El-Mimouni, Mohamed, Aarab, Abdellatif, Lakhloufi, Abdellah, Hamzaoui, Abderrazak, Aabi, Ayoub, and Benyas, Kawtar
- Subjects
HYDROTHERMAL alteration ,REMOTE sensing ,MINERAL industries ,ECONOMIC development - Abstract
This study aims to map minerals of hydrothermal alteration zones in the Rehamna Massif, formerly site of large exploitation of Pb-Zn, Ba-Pb and W-Sn hosted within the Paleozoic basement, using the advantages of remote sensing technique. In this regard, ASTER remote sensing data have been used as a substrate for spectral processing, namely band ratios, to identify hydrothermal alteration zones characteristic of polymetallic mineralization. Band ratio technique leads us to map the Phyllic, Argillic, Prophylitic, Oxidation and kaolinite zones. Other ratios such as Muscovite, Allunite, Calcite and Fe-oxides were also computed. The areas reported were locally compared with the geological setting. The compilations of the results facilitate the identification of eight potential sites suitable for a possible tactical research phase. These results can encourage mining exploration and guide mining companies to the most potentially ore-bearing sites and support the economic development of the Rehamna area. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
10. Contribution of the Airborne Magnetic Field to the Structural Study of the Variscan Granitoid of Rehamna, Morocco
- Author
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Kawtar Benyas, Abdellatif Aarab, Abdellah Lakhloufi, Abdelmounim Qarbous, Ahmed Manar, Mounir Amar, Assia Idrissi, and Mohamed Elmimouni
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Geology ,QE1-996.5 - Abstract
At the Moroccan Western Meseta, the study of airborne magnetic data from the Rehamna massif, using the potential aeromagnetic methods, has allowed us to improve and describe the geometry of the geological structures of the Rehamna variscan granitoids and their subsurface components. These methods have proven to be an adequate geophysical technique to study the deep and subsurface structures of this area covered by a thick Mesozoic-Cenozoic sedimentary cover. The calculation of the reduced map to pole and upward continuation of the reduced residual magnetic field to the pole at 2 km to 30 km shows the close relationship between the positive anomalies and the deep magma bodies that outcrop locally in the tectonic contacts; thus, a strong correlation between the aeromagnetic lineaments and the regional crustal-scale faults-oriented N-S to NE-SW. The calculation of the Euler deconvolution of these lineaments, using the different structural indices, shows a depth of aeromagnetic lineaments about ten kilometers due to the presence of a very thick sedimentary layer. The final structural map reveals four groups of faults oriented, respectively NNW-SSE, N-S, NNE-SSW, NE-SW, and E-W.
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- 2022
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11. TheStreptococcus pyogenesM protein is involved in phenotypic resistance to phage A25 infection in presence of human serum
- Author
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Schiavolin, Lionel, primary, Steinmetz, Jenny, additional, Botquin, Gwenaëlle, additional, Delforge, Valérie, additional, Lakhloufi, Dalila, additional, Smeesters, Pierre R., additional, and Botteaux, Anne, additional
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- 2024
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12. Electrochemical behavior and degradation mechanism of lithium disilicate glass ceramics in acidic environment
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Lakhloufi, Soraya, primary, Labjar, Najoua, additional, Labjar, Houda, additional, Serghini‐Idrissi, Malika, additional, and El Hajjaji, Souad, additional
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- 2024
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13. Electrochemical behavior and surface stability of dental zirconia ceramics in acidic environments
- Author
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Lakhloufi, Soraya, primary, Labjar, Najoua, additional, Labjar, Houda, additional, Serghini- Idrissi, Malika, additional, and El Hajjaji, Souad, additional
- Published
- 2023
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14. Metallic coatings of MEMS at low temperatures: stress, elasticity and non-linear dissipation
- Author
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Collin, Eddy, Kofler, Johannes, Lakhloufi, Sabine, Pairis, Sebastien, Bunkov, Yuriy M., and Godfrin, Henri
- Subjects
Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
We present mechanical measurements performed at low temperatures on cantilever-based microelectro-mechanicalstructures(MEMS) coated with a metallic layer. Two very different coatings are presented in order to illustrate the capabilities of the present approach, namely (soft) aluminum and (hard) niobium oxide. The temperature is used as a control parameter to access materials properties. We benefit from low temperature techniques to extract a phase-resolved measurement of the first mechanical resonance mode in cryogenic vacuum. By repeating the experiment on the same samples, after multiple metallic depositions, we can determine accurately the contribution of the coating layers to the mechanical properties in terms of surface stress, additional mass, additional elasticity and damping. Analytic theoretical expressions are derived and used to fit the data. Taking advantage of the extremely broad dynamic range provided by the technique, we can measure the anelasticity of the thin metallic film. The key parameters describing the metals' dynamics are analyzed in an original way in order to provide new experimental grounds for future theoretical modelings of the underlying mechanisms.
- Published
- 2013
15. Electrochemical Behavior and Surface Characterization of Two Dental Materials: Glass Ceramic and Zirconia in Artificial Saliva
- Author
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Lakhloufi, Soraya, Labjar, Houda, El Hamdouni, Youssra, Bouhouche, Ichraq, Labjar, Najoua, Dahrouch, Abdelouahed, Serghini-Idriissi, Malika, El Yamani, Amal, and El Hajjaji, Souad
- Published
- 2020
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16. Biological treatment of leachate from the uncontrolled landfill: evaluation of toxicity and heavy metals reduction
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Nezha Mherzi, Fatima Lamchouri, Mohamed Yassine Lakhloufi, Abdelouahab Zalaghi, and Hamid Toufik
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Ecology ,General Earth and Planetary Sciences ,Ecology, Evolution, Behavior and Systematics ,General Environmental Science - Published
- 2023
17. Evaluation of anthropic activities impact through the monitoring of aquatic fauna on Oued Lârbaa in Taza City of Morocco
- Author
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Lakhloufi, Mohamed Yassine, Lamchouri, Fatima, El Haissoufi, Mohamed, Boulfia, Mohamed, Zalaghi, Abdelouahab, and Toufik, Hamid
- Published
- 2021
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18. Analysis of Global Collection of Group A Streptococcus Genomes Reveals that the Majority Encode a Trio of M and M-Like Proteins
- Author
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Hannah R. Frost, Mark R. Davies, Valérie Delforge, Dalila Lakhloufi, Martina Sanderson-Smith, Velusamy Srinivasan, Andrew C. Steer, Mark J. Walker, Bernard Beall, Anne Botteaux, and Pierre R. Smeesters
- Subjects
Streptococcus pyogenes ,Mga regulon ,M-like proteins ,global GAS diversity ,Microbiology ,QR1-502 - Abstract
ABSTRACT The core Mga (multiple gene activator) regulon of group A Streptococcus (GAS) contains genes encoding proteins involved in adhesion and immune evasion. While all GAS genomes contain genes for Mga and C5a peptidase, the intervening genes encoding M and M-like proteins vary between strains. The genetic make-up of the Mga regulon of GAS was characterized by utilizing a collection of 1,688 GAS genomes that are representative of the global GAS population. Sequence variations were examined with multiple alignments, and the expression of all core Mga regulon genes was examined by quantitative reverse transcription-PCR in a representative strain collection. In 85.2% of the sampled genomes, the Mga locus contained genes encoding Mga, Mrp, M, Enn, and C5a peptidase proteins. These isolates account for 53% of global infections. Only 9.1% of genomes did not contain either an mrp or an enn gene. The pairwise identity within Enn (68.6%) and Mrp (83.2%) protein sequences was higher than within M proteins (44.7%). Gene expression varied between strains tested, but high expression was recorded for all genes in at least one strain. Previous nomenclature issues were clarified with molecular gene definitions. Our findings support a shift in focus in the GAS research field to further consider the role of Mrp and Enn in virulence and vaccine development. IMPORTANCE While the GAS M protein has been the leading vaccine target for decades, the bacteria encode many other virulence factors of interest for vaccine development. In this work, we show that emm-like genes are encoded in a remarkable majority of GAS genomes and expressed at a level similar to that for the emm gene. In collaboration with the U.S. Centers for Disease Control, we developed molecular definitions of the different emm and emm-like gene families. This clarification should abrogate mistyping of strains, especially in the area of whole-genome typing. We have also updated the emm-typing collection by removing emm-like gene sequences and provided in-depth analysis of Mrp and Enn protein sequence structure and diversity.
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- 2020
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19. Multiple proteins arising from a single gene: The role of the Spa33 variants in Shigella T3SS regulation
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Mahendar Kadari, Dalila Lakhloufi, Valérie Delforge, Virginie Imbault, David Communi, Pierre Smeesters, and Anne Botteaux
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bacterial virulence ,pathogenesis ,secretion regulation ,Shigella flexneri ,type 3 secretion system ,Microbiology ,QR1-502 - Abstract
Abstract Shigella invasion and dissemination in intestinal epithelial cells relies on a type 3 secretion system (T3SS), which mediates translocation of virulence proteins into host cells. T3SSs are composed of three major parts: an extracellular needle, a basal body, and a cytoplasmic complex. Three categories of proteins are hierarchically secreted: (a) the needle components, (b) the translocator proteins which form a pore (translocon) inside the host cell membrane and (c) the effectors interfering with the host cell signaling pathways. In the absence of host cell contact, the T3SS is maintained in an “off” state by the presence of a tip complex. Secretion is activated by host cell contact which allows the release of a gatekeeper protein called MxiC. In this work, we have investigated the role of Spa33, a component of the cytoplasmic complex, in the regulation of secretion. The spa33 gene encodes a 33‐kDa protein and a smaller fragment of 12 kDa (Spa33C) which are both essential components of the cytoplasmic complex. We have shown that the spa33 gene gives rise to 5 fragments of various sizes. Among them, three are necessary for T3SS. Interestingly, we have shown that Spa33 is implicated in the regulation of secretion. Indeed, the mutation of a single residue in Spa33 induces an effector mutant phenotype, in which MxiC is sequestered. Moreover, we have shown a direct interaction between Spa33 and MxiC.
- Published
- 2019
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20. En guerra con los berberiscos, Una historia de los conflictos en la costa mediterránea.
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Balouati Lakhloufi, Selim
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INFORMATION organization ,INTERNATIONAL relations ,ESPIONAGE ,PROLOGUES & epilogues ,KINGS & rulers ,OTTOMAN Empire ,BIBLIOGRAPHIC databases ,CYBERTERRORISM - Abstract
Copyright of Revista Universitaria de Historia Militar (RUHM) is the property of Centro de Estudios de la Guerra and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2024
21. Biological treatment of leachate from the uncontrolled landfill: evaluation of toxicity and heavy metals reduction
- Author
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Mherzi, Nezha, primary, Lamchouri, Fatima, additional, Lakhloufi, Mohamed Yassine, additional, Zalaghi, Abdelouahab, additional, and Toufik, Hamid, additional
- Published
- 2023
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22. Biofilm Decontamination by Cold Atmospheric Plasma for Endoscope Reprocessing
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Serra, Teo, Remy, Antoine, Zveny, Juliette, Lakhloufi, Dalila, Devière, Jacques, Botteaux, Anne, Reniers, François, Delchambre, Alain, Nonclercq, Antoine, Serra, Teo, Remy, Antoine, Zveny, Juliette, Lakhloufi, Dalila, Devière, Jacques, Botteaux, Anne, Reniers, François, Delchambre, Alain, and Nonclercq, Antoine
- Abstract
Objective: This study evaluates the application of a plasma discharge for the decontamination and removal of bacterial biofilms in small-diameter polytetrafluoroethylene (PTFE) tubes. The latter simulates the environments of an endoscope working channel., info:eu-repo/semantics/nonPublished
- Published
- 2023
23. Exploiting Aeromagnetic and Gravity Data Interpretation to Delineate Massif Deposits of Rehamna Area (Western Meseta-Morocco)
- Author
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Mohamed El-Mimouni, Abdelmounim Qarbous, Abdellah Lakhloufi, Mounir Amar, Ahmed Manar, Assia Idrissi, Abdellatif Aarab, and Kawtar Benyas
- Subjects
QE1-996.5 ,Gravity (chemistry) ,geography ,geography.geographical_feature_category ,Lineament ,Vertical derivative ,Geochemistry ,Data interpretation ,Geology ,Massif ,Gravity gradient ,Geological structure ,Gravimetry - Abstract
The analysis of the magnetic signatures and gravity gradient values of the Rehamna Massif south of the Moroccan Western Meseta by using Geosoft Oasis Montaj 7.0.1 software, allowed us to detect several useful anomalies to be exploited and which are related to magmatic bodies and structural features within the study area. These data were analyzed by applying several techniques, including the horizontal gradient filters combined with the first vertical derivative. Subsurface structures; such as geological boundaries, faults, dykes and folds, were visualized as lineaments on geophysical maps, then results were compared with structural features provided by previous studies in the region. Thus, the Rehamna Massif structural map shows sets of linear features which may represent faults or boundaries of geological structures, which can be either faults or boundaries of geological structures, and they are mostly oriented in the directions: N-S, NNE-SSW, NE-SW, E-W with the predominance of the NNE-SSW to NE-SW directions. In addition, the super position of the minerals bearing beds or formations were distinguished from gravity and magnetic data processing results. Some of the recognized anomalies are related to the existence of precious metals which belong to the granitic bodies within the study area.
- Published
- 2021
24. Contribution of Electrical Resistivity Tomography (ERT) and Vertical Electrical Sounding (VES) to delineate the structural organization of the Palaeozoic Zone in the Rabat-Tiet region (Morocco).
- Author
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MONSARD, Nicolas Isaac, BENCHEKROUN, Sabah, AARAB, Abdellatif, and LAKHLOUFI, Abdellah
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ELECTRICAL resistivity ,LIMESTONE quarries & quarrying ,TOMOGRAPHY ,LIMESTONE ,GEOLOGICAL surveys ,BUSINESS names ,CONGLOMERATE - Abstract
In this geophysical study, we carried out four Electrical Resistivity Tomography (ERT) proflles and one Vertical Electrical Sounding (VES) in the Palaeozoic Zone in the Rabat-Tiet region, Morocco. Measurements were accomplished in and around the limestone quarry exploited by the company named 'Société Des Granulats de Tiet' (SDGT) located in our study area. The aim of this study is to delineate the structural organization, especially the spatial distribution of limestone deposits which represents the main formations of this Palaeozoic zone in the Rabat-Tiet region. Analysis of 2D inverse model resistivity sections show some anomalous contacts and the existence of subsurface lenticular bodies with resistivity going from 100 to 1500 Ωm, potentially corresponding to limestone rock. Also, vertical electrical sounding achieving near the SDGT showed a layer with a resistivity of 317 Ωm at 6 m depth interpreted as limestone conglomerates or limestone deposits. More, during our geological survey, we observed along the Oued Bou Regreg valley and in some abandoned quarries located in the same area, lenticular blocks with different sizes globally having an NNW-SSE direction. These results contributed, even in small scall, to clarify the structural organization of the Palaeozoic Zone in the Rabat-Tiet region. To map out with high precision this geological complex region, more electrical and seismic proflles as well geochemical studies are recommended. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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25. Financial inclusion, income inequality and economic growth. The case of Morocco
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Jamal Sekali and Tarek Lakhloufi
- Subjects
top 10% ,Financial inclusion ,economic growth ,GINI index ,income inequality - Abstract
Résumé: L’inclusion financière comme une solution alternative pour la réduction des inégalités de revenus, nous avons examiné, les effets du développement de l’inclusion financière sur les inégalités de revenus au Maroc. Nos résultats montrent que l’indice de l’inclusion financière qui mesure la dimension de l'accès au secteur bancaire réduit de manière significative les inégalités de revenus au Maroc. Conformément aux études du FMI et d’autres travaux de chercheurs de la banque mondiale concluent à une forte corrélation entre l’inclusion financière et la réduction des inégalités de revenus. Les résultats empiriques ont montré aussi que la croissance économique dans le Maroc accroît les inégalités dans la répartition de revenus. Cela signifie que la croissance économique réalisée dans ces pays est encore insuffisante pour diminuer de manière significative les inégalités de revenus, qui continuent d’afficher une résistance à la hausse comme en témoigne le dernier rapport mondial sur les inégalités au monde. Mots Clés : Inclusion financière, inégalité de revenus, croissance économique, les 10% les plus aisés, indice de GINI. Summary: Financial inclusion as an alternative solution for reducing income inequalities, we have examined, the effects of the development of financial inclusion on income inequalities in Morocco. Our results show that the financial inclusion index which measures the dimension of access to the banking sector significantly reduces income inequalities in Morocco. In line with IMF studies and other work by World Bank researchers, there is a strong correlation between financial inclusion and reduced income inequality. Empirical results have also shown that economic growth in Morocco increases inequalities in the distribution of income. This means that the economic growth achieved in these countries is still insufficient to significantly reduce income inequalities, which continue to show upward resistance as evidenced by the latest Global Inequality Report. Key words : Financial inclusion, income inequality, economic growth, top 10%, GINI index.
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- 2022
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26. Antibody response to gut microbiome bacteria in human alcoholic liver disease
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Putignano, Antonella, primary, Sharma, Shilpee, additional, Thiriard, Anaïs, additional, Lakhloufi, Dalila, additional, Jiang, Yiwei, additional, Botteaux, Anne, additional, Trépo, Eric, additional, Degré, Delphine, additional, Moreno, Christophe, additional, Gustot, Thierry, additional, and Marchant, Arnaud, additional
- Published
- 2022
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27. Développement financier et croissance économique dans la région MENA : Une approche en données de panel
- Author
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SEKALI, Jamal and LAKHLOUFI, Tarek
- Subjects
Développement financier ,croissance économique ,marchés boursiers ,institutions financières ,région MENA ,P-ARDL - Abstract
Dans cet article, nous examinons le rôle du développement financier (marchés boursiers et institutions financières) sur la croissance économique des 10 pays de la région MENA. La plupart des études empiriques dans la littérature mesurent le niveau de développement financier à l'aide d'une seule mesure, le total des crédits au secteur privé provenant de banques et d'autres institutions financières en pourcentage du PIB. Pour surmonter ce problème, nous utilisons des mesures d’indice pour le développement des institutions financières et le développement des marchés boursiers. Les résultats montrent que le coefficient de l’indice de développement financier, à la fois en bourse et en institution financière, est significatif dans toutes les régressions. Pour le développement des institutions financières, les résultats suggèrent que la relation entre développement des institutions financières et croissance est positive et significative dans les pays de l’Afrique du Nord et les pays du Moyen-Orient. Les résultats empiriques basés sur les estimations du PMG suggèrent que la relation entre le développement des marchés boursiers et la croissance économique est positive et significative dans les pays de l’Afrique du Nord et les pays du Moyen-Orient., Alternatives Managériales Economiques, Vol 4, No 2 (2022)
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- 2022
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28. LA PERFORMANCE LOGISTIQUE DU MAROC, DE LA FRANCE ET DE L’ESPAGNE : APPROCHE COMPARATIVE ET ANALYTIQUE
- Author
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LAKHLOUFI, Tarek and Sekali, Jamal
- Subjects
Performance logistique – Indice de performance logistique - Score – Coût –Qualité-Délai - Abstract
La performance logistique a été, et continue d’être, un sujet de recherche et d’investigation épineuse. Elle a suscité l’intérêt des décideurs politiques, des économistes, des industriels et des chercheurs tant au niveau des stratégies pour l’atteindre qu’au niveau des outils de son évaluation pour rectifier le cap. L’objectif de cet article est d’évaluer la performance logistique de la France, de l’Espagne et du Maroc à travers l’indice de la performance logistique élaborée par la banque mondiale. Les résultats de notre étude font ressortir que les pays de la France et de l’Espagne ont atteint un score de performance très élevé par rapport au Maroc qui devrait déployer encore des efforts supplémentaires pour améliorer sa performance logistique., Revue des Etudes Multidisciplinaires en Sciences Economiques et Sociales, Vol. 7, No 1 (2022)
- Published
- 2022
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29. Mosaicity and structural fatigability of a gradual spin-crossover single crystal
- Author
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Guionneau, Philippe, Lakhloufi, Sabine, Lemée-Cailleau, Marie-Hélène, Chastanet, Guillaume, Rosa, Patrick, Mauriac, Cindy, and Létard, Jean-François
- Published
- 2012
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30. Electrochemical Behavior and Surface Characterization of Two Dental Materials: Glass Ceramic and Zirconia in Artificial Saliva
- Author
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Souad El Hajjaji, Youssra El Hamdouni, Ichraq Bouhouche, Abdelouahed Dahrouch, Houda Labjar, Najoua Labjar, Soraya Lakhloufi, Malika Serghini-Idriissi, and Amal El Yamani
- Subjects
Saliva ,Materials science ,Glass-ceramic ,020209 energy ,Mechanical Engineering ,02 engineering and technology ,Microstructure ,Dielectric spectroscopy ,law.invention ,020303 mechanical engineering & transports ,0203 mechanical engineering ,Chemical engineering ,Mechanics of Materials ,law ,visual_art ,0202 electrical engineering, electronic engineering, information engineering ,visual_art.visual_art_medium ,Degradation (geology) ,General Materials Science ,Cubic zirconia ,Ceramic ,Safety, Risk, Reliability and Quality ,Dissolution - Abstract
Artificial saliva was used as a degradation medium to assess the effect of saliva on the surface condition, microstructure, chemical composition, and degradation behavior of dental materials. This is done using X-ray diffraction, SEM-coupled energy-dispersive spectrometry (EDX) and electrochemical impedance spectroscopy of these ceramics before and after 21 days of immersion in the salivary medium. The aim of this research was to evaluate the degradation of glass ceramics and zirconia after immersion in Ringer’s solution for 7, 14, 21 days at 37 °C and pH = 7.3 by XRD, SEM/EDX and their electrochemical behavior by E.I.S. These results indicate that there is a significant effect of artificial saliva on the materials studied; this effect is manifested by degradation either by release or dissolution of certain ionic compounds. It is also important to note that this dissolution could lead to the deposition of layers on the surface of dental materials; this is all the more important depending on the immersion time.
- Published
- 2020
31. Electrochemical behavior and surface characterization of dental materials in artificial salivary
- Author
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S. El Hajjaji, A. El Yamani, I. Bouhouche, Y. El Hamdouni, S. Lakhloufi, Najoua Labjar, Houda Labjar, M. El Mahi, El Mostapha Lotfi, Abdelouahed Dahrouch, and M. Serghini-Idriissi
- Subjects
010302 applied physics ,Materials science ,Ionic bonding ,02 engineering and technology ,Electrolyte ,021001 nanoscience & nanotechnology ,Microstructure ,Electrochemistry ,01 natural sciences ,Dielectric spectroscopy ,Chemical engineering ,visual_art ,0103 physical sciences ,Immersion (virtual reality) ,visual_art.visual_art_medium ,Ceramic ,0210 nano-technology ,Dissolution - Abstract
Research concerning the applications of ceramic biomaterials as dental restorative materials is of particular interest for the study of the physico-chemical, mechanical and microstructural behavior with a multitude of techniques. Nevertheless, the wealth of scientific articles in this field remains vast and poor in terms of all-ceramic restorative materials, their ageing and electrochemical degradation behavior utilizing the electrochemical impedance spectroscopy, in contact with an electrolytic solution which can cause and exhibit a very remarkable variation in the surface state and variation in the stability of the electrochemical behavior of these dental materials, which can be influenced by pH, temperature and the medium variations. Ringer's solution as artificial saliva has been used as a degradation medium to evaluate the effect of saliva on the microstructure, surface condition, chemical composition and degradation behavior of dental materials. This is done using X-ray diffraction, SEM-coupled energy dispersive spectrometry (EDX) and electrochemical impedance spectroscopy as a technique to assess the interface degradation behavior of these materials after 21 days of immersion in salivary medium. The aim of this study was to identify and evaluate the changes in the electrochemical behavior of these 2 ceramic materials, Feldspar and Alumina after immersion in Ringer solution for 7, 14, 21 days at 37 °C and pH = 7.3 by XRD, SEM / EDX and their electrochemical behavior by EIS. These results indicate that there is a significant effect of synthetic Ringer's salivary solution on the ceramics studied; this effect is manifested by degradation through the release and/or dissolution of certain ionic compounds. It is also important to note that this dissolution could result in the deposition of layers on the surface of dental materials; this is even more important depending on the immersion time.
- Published
- 2020
32. ANALYSE DE L���EFFICIENCE DES PORTS MARITIMES AFRICAINS : LE CAS DE TANGER MED, DURBAN, MOMBASA ET ABIDJAN
- Author
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LAKHLOUFI, Tarek and SEKALI, Jamal
- Subjects
Africa - Seaports - Efficiency - DEA- CRS ��� VRS - Abstract
The importance of seaports in the national and international economic scene is no longer in doubt. It has thus become obvious for them that their efficiency, and even their sustainability in a world of fierce competition, strongly depends on the optimisation of the input-output ratio. The question of assessing port efficiency is becoming increasingly important in the port sector, as investments in this sector are huge but performance will not always depend on them. Therefore, the objective of this paper is to assess the efficiency of the seaports of Tangier Med, Durban, Mombasa and Abidjan while using the non-parametric enveloped data analysis (DEA) approach., Revue Economie, Gestion et Soci��t��, �������� 1, ������ 34 (2022)
- Published
- 2022
- Full Text
- View/download PDF
33. Moroccan Hercynian history : another version of the story
- Author
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Abdellah Lakhloufi
- Subjects
General Engineering - Published
- 2021
34. Mosaicity of Spin-Crossover Crystals
- Author
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Sabine Lakhloufi, Elodie Tailleur, Wenbin Guo, Frédéric Le Gac, Mathieu Marchivie, Marie-Hélène Lemée-Cailleau, Guillaume Chastanet, and Philippe Guionneau
- Subjects
mosaicity ,spin crossover ,X-ray diffraction ,fatigability ,single crystal ,phase transition ,structural disorder ,Crystallography ,QD901-999 - Abstract
Real crystals are composed of a mosaic of domains whose misalignment is evaluated by their level of “mosaicity” using X-ray diffraction. In thermo-induced spin-crossover compounds, the crystal may be seen as a mixture of metal centres, some being in the high-spin (HS) state and others in the low spin (LS) state. Since the volume of HS and LS crystal packings are known to be very different, the assembly of domains within the crystal, i.e., its mosaicity, may be modified at the spin crossover. With little data available in the literature we propose an investigation into the temperature dependence of mosaicity in certain spin-crossover crystals. The study was preceded by the examination of instrumental factors, in order to establish a protocol for the measurement of mosaicity. The results show that crystal mosaicity appears to be strongly modified by thermal spin-crossover; however, the nature of the changes are probably sample dependent and driven, or masked, in most cases by the characteristics of the crystal (disorder, morphology …). No general relationship could be established between mosaicity and crystal properties. If, however, mosaicity studies in spin-crossover crystals are conducted and interpreted with great care, they could help to elucidate crucial crystal characteristics such as mechanical fatigability, and more generally to investigate systems where phase transition is associated with large volume changes.
- Published
- 2018
- Full Text
- View/download PDF
35. Contribution of the Airborne Magnetic Field to the Structural Study of the Variscan Granitoid of Rehamna, Morocco
- Author
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Benyas, Kawtar, primary, Aarab, Abdellatif, additional, Lakhloufi, Abdellah, additional, Qarbous, Abdelmounim, additional, Manar, Ahmed, additional, Amar, Mounir, additional, Idrissi, Assia, additional, and Elmimouni, Mohamed, additional
- Published
- 2022
- Full Text
- View/download PDF
36. Moroccan Hercynian history : another version of the story
- Author
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Lakhloufi, Abdellah, primary
- Published
- 2021
- Full Text
- View/download PDF
37. Antibody response to gut microbiome bacteria in human alcoholic liver disease
- Author
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Antonella Putignano, Shilpee Sharma, Anaïs Thiriard, Dalila Lakhloufi, Yiwei Jiang, Anne Botteaux, Eric Trépo, Delphine Degré, Christophe Moreno, Thierry Gustot, and Arnaud Marchant
- Subjects
Hepatology - Published
- 2022
38. The Nador west med port complex serving the territorial attractiveness of the eastern region: : Qualitative study
- Author
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LAKHLOUFI TAREK and EL MAJIDI BRAHIM
- Subjects
Attractivité territoriale ,Port maritime ,Seaport ,Eastern Region ,Territorial Attractiveness ,région de l'Oriental ,NWM - Abstract
This article tries to assess the influence of the Nador west med (NWM) port complex on the territorial attractiveness of the eastern region in a context marked by the implementation of the Royal initiative for the development of the Eastern Region (2003), the implementation of the policy of large building sites and the territorialization of sectoral strategies. The achievement of this objective led us to use qualitative tools, notably the interview guide. The sample of this study has confirmed the favourable impact of this port complex on the territorial attractiveness of the region, while highlighting the conditions related in particular to fiscal advantages, to the formalization of the informal sector and to the promotion of the territorial offer. This trial took place in a pandemic situation (COVID19) negatively affecting the duration of the interviews with the interviewees., Cet article essaie d’évaluer l’influence de complexe portuaire Nador west med (NWM) sur l’attractivité territoriale de la région de l’oriental dans un contexte marqué par l’implémentation de l’initiative royale du développement de l’oriental (2003), de la mise en œuvre de la politique de grands chantiers et de la territorialisation des stratégies sectorielles. L’aboutissement de cet objectif nous a conduit à faire recours aux outils qualitatifs notamment le guide d’entretien. L’échantillon de cette étude a confirmé l’impact favorable de ce complexe portuaire sur l’attractivité territoriale de la région, tout en mettant en avant des conditions liées notamment aux avantages fiscaux, à la formalisation de l’informel, à la promotion de l’offre territoriale. Cet essai s’est déroulé dans une situation pandémique (COVID19) affectant négativement la durée des entretiens avec les interviewés.
- Published
- 2021
39. Port logistics and Economic growth: An empirical investigation of Morocco
- Author
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LAKHLOUFI, Tarek and MOUSSAMIR, Abdelhak
- Subjects
Port logistics ,Economic growth ,ARDL ,Port traffic - Abstract
Port logistics is an inevitable link in the chain of international logistics in a general way and in international trade in a particular way. According to UNCTAD (2013), the maritime link accounts for 80% of the world’s trade volume, although the physical continuity of freight transport requires the use of multimodal transport systems. In this sense Morocco has been engaged over the last two decades, in a process of considerable port reforms, aimed at making its port logistics a locomotive of its economy. Indeed, the port logistics in Morocco has achieved important advances, in terms of maritime connectivity, and quality of port infrastructure, which has improved the Moroccan maritime presence on the international scene. Therefore, it is time to assess the impact of these efforts on economic growth, since it plays an important role in political discourse and economic debates. Using the autoregressive model with staggered delays ARDL, we plan to answer the following question how port logistics can influence Moroccan economic growth? The econometric estimates allowed us to confirm the positive effect of the port logistics on the economic growth of Morocco. Thus, these results approved the theoretical and empirical predictions, Alternatives Managériales Economiques, Vol. 2, No 3 (2020)
- Published
- 2020
- Full Text
- View/download PDF
40. Evaluation of anthropic activities impact through the monitoring of aquatic fauna on Oued Lârbaa in Taza City of Morocco
- Author
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Fatima Lamchouri, Hamid Toufik, Mohamed Yassine Lakhloufi, Mohamed Boulfia, Abdelouahab Zalaghi, and Mohamed El Haissoufi
- Subjects
Pollution ,010504 meteorology & atmospheric sciences ,media_common.quotation_subject ,Fauna ,Biodiversity ,010501 environmental sciences ,Management, Monitoring, Policy and Law ,01 natural sciences ,Rivers ,Animals ,Industry ,Cities ,0105 earth and related environmental sciences ,General Environmental Science ,media_common ,Invertebrate ,Hydrology ,General Medicine ,Total dissolved solids ,Invertebrates ,Salinity ,Morocco ,Benthic zone ,Environmental science ,Surface water ,Environmental Monitoring - Abstract
The accelerated development of industrial activities in Taza City implies the appearance of new sources of pollution that directly affect the quality of surface water. This is reflected in the structure and biodiversity of the city’s Oueds, particularly Oued Lârbaa, which receives the majority of the pollution load produced. Therefore, the study of the benthic fauna can be an effective tool to characterize the state of the waters of Oued Lârbaa. The objective of our study is to assess the impact of anthropogenic activities on Oued Lârbaa, through the monitoring of physicochemical parameters (hydrogen potential (pH), salinity, conductivity, total dissolved solids (TDS), and oxidation–reduction potential) and biological biodiversity represented by benthic macroinvertebrates at 10 stations, during two periods of the year: a wet period (December 2018) and a dry period (June 2019). The spatial variations of recorded physicochemical parameters, as well as the effect of anthropogenic activities, control the diversity of macroinvertebrates at Oued Lârbaa. In relation to these data, the first stations of our study (S1-S2-S3) are moderately polluted, characterized by an important biodiversity, which includes sensitive species (Crustacea, Trichoptera, Ephemeroptera), and other resistant species (Diptera). The stations S4-S5-S6-S7-S8-S9 and S10 are characterized by a low biodiversity represented mainly by macroinvertebrates that colonize waters of critical quality (Diptera). The statistical study by principal component analysis consisting of a projection of the biological (benthic macroinvertebrates) and physicochemical variables obtained from each of the two study periods on a two-dimensional factorial plane shows the existing correlations between these variables.
- Published
- 2020
41. Analysis of Global Collection of Group A Streptococcus Genomes Reveals that the Majority Encode a Trio of M and M-Like Proteins
- Author
-
Mark J. Walker, Mark R. Davies, Martina L. Sanderson-Smith, Hannah R Frost, Valérie Delforge, Dalila Lakhloufi, Bernard Beall, Andrew C Steer, Pierre R. Smeesters, Velusamy Srinivasan, and Anne Botteaux
- Subjects
DNA, Bacterial ,0301 basic medicine ,Streptococcus pyogenes ,Virulence Factors ,030106 microbiology ,Population ,lcsh:QR1-502 ,Virulence ,Locus (genetics) ,Mga regulon ,Biology ,Regulon ,Microbiology ,Genome ,lcsh:Microbiology ,Clinical Science and Epidemiology ,03 medical and health sciences ,Bacterial Proteins ,stomatognathic system ,otorhinolaryngologic diseases ,Gene family ,education ,Molecular Biology ,Gene ,Whole genome sequencing ,Genetics ,Antigens, Bacterial ,education.field_of_study ,M-like proteins ,Whole Genome Sequencing ,Généralités ,bacterial infections and mycoses ,QR1-502 ,stomatognathic diseases ,030104 developmental biology ,Carrier Proteins ,global GAS diversity ,Genome, Bacterial ,Research Article ,Bacterial Outer Membrane Proteins - Abstract
The core Mga (multiple gene activator) regulon of group A Streptococcus (GAS) contains genes encoding proteins involved in adhesion and immune evasion. While all GAS genomes contain genes for Mga and C5a peptidase, the intervening genes encoding M and M-like proteins vary between strains. The genetic make-up of the Mga regulon of GAS was characterized by utilizing a collection of 1,688 GAS genomes that are representative of the global GAS population. Sequence variations were examined with multiple alignments, and the expression of all core Mga regulon genes was examined by quantitative reverse transcription-PCR in a representative strain collection. In 85.2% of the sampled genomes, the Mga locus contained genes encoding Mga, Mrp, M, Enn, and C5a peptidase proteins. These isolates account for 53% of global infections. Only 9.1% of genomes did not contain either an mrp or an enn gene. The pairwise identity within Enn (68.6%) and Mrp (83.2%) protein sequences was higher than within M proteins (44.7%). Gene expression varied between strains tested, but high expression was recorded for all genes in at least one strain. Previous nomenclature issues were clarified with molecular gene definitions. Our findings support a shift in focus in the GAS research field to further consider the role of Mrp and Enn in virulence and vaccine development.IMPORTANCE While the GAS M protein has been the leading vaccine target for decades, the bacteria encode many other virulence factors of interest for vaccine development. In this work, we show that emm-like genes are encoded in a remarkable majority of GAS genomes and expressed at a level similar to that for the emm gene. In collaboration with the U.S. Centers for Disease Control, we developed molecular definitions of the different emm and emm-like gene families. This clarification should abrogate mistyping of strains, especially in the area of whole-genome typing. We have also updated the emm-typing collection by removing emm-like gene sequences and provided in-depth analysis of Mrp and Enn protein sequence structure and diversity., SCOPUS: ar.j, info:eu-repo/semantics/published
- Published
- 2020
42. Analysis of Global Collection of Group A Streptococcus Genomes Reveals that the Majority Encode a Trio of M and M-Like Proteins
- Author
-
Suen, G, Frost, HR, Davies, MR, Delforge, V, Lakhloufi, D, Sanderson-Smith, M, Srinivasan, V, Steer, AC, Walker, MJ, Beall, B, Botteaux, A, Smeesters, PR, Suen, G, Frost, HR, Davies, MR, Delforge, V, Lakhloufi, D, Sanderson-Smith, M, Srinivasan, V, Steer, AC, Walker, MJ, Beall, B, Botteaux, A, and Smeesters, PR
- Abstract
The core Mga (multiple gene activator) regulon of group A Streptococcus (GAS) contains genes encoding proteins involved in adhesion and immune evasion. While all GAS genomes contain genes for Mga and C5a peptidase, the intervening genes encoding M and M-like proteins vary between strains. The genetic make-up of the Mga regulon of GAS was characterized by utilizing a collection of 1,688 GAS genomes that are representative of the global GAS population. Sequence variations were examined with multiple alignments, and the expression of all core Mga regulon genes was examined by quantitative reverse transcription-PCR in a representative strain collection. In 85.2% of the sampled genomes, the Mga locus contained genes encoding Mga, Mrp, M, Enn, and C5a peptidase proteins. These isolates account for 53% of global infections. Only 9.1% of genomes did not contain either an mrp or an enn gene. The pairwise identity within Enn (68.6%) and Mrp (83.2%) protein sequences was higher than within M proteins (44.7%). Gene expression varied between strains tested, but high expression was recorded for all genes in at least one strain. Previous nomenclature issues were clarified with molecular gene definitions. Our findings support a shift in focus in the GAS research field to further consider the role of Mrp and Enn in virulence and vaccine development.IMPORTANCE While the GAS M protein has been the leading vaccine target for decades, the bacteria encode many other virulence factors of interest for vaccine development. In this work, we show that emm-like genes are encoded in a remarkable majority of GAS genomes and expressed at a level similar to that for the emm gene. In collaboration with the U.S. Centers for Disease Control, we developed molecular definitions of the different emm and emm-like gene families. This clarification should abrogate mistyping of strains, especially in the area of whole-genome typing. We have also updated the emm-typing collection by removing emm-like gene se
- Published
- 2020
43. Analysis of Global Collection of Group A Streptococcus Genomes Reveals that the Majority Encode a Trio of M and M-Like Proteins
- Author
-
Frost, Hannah R C H., Davies, Mark R, Delforge, Valérie, Lakhloufi, Dalila, Sanderson-Smith, Martina L, Srinivasan, Velusamy, Steer, Andrew C, Walker, M., Beall, Bernard W, Botteaux, Anne, Smeesters, Pierre, Frost, Hannah R C H., Davies, Mark R, Delforge, Valérie, Lakhloufi, Dalila, Sanderson-Smith, Martina L, Srinivasan, Velusamy, Steer, Andrew C, Walker, M., Beall, Bernard W, Botteaux, Anne, and Smeesters, Pierre
- Abstract
The core Mga (multiple gene activator) regulon of group A Streptococcus (GAS) contains genes encoding proteins involved in adhesion and immune evasion. While all GAS genomes contain genes for Mga and C5a peptidase, the intervening genes encoding M and M-like proteins vary between strains. The genetic make-up of the Mga regulon of GAS was characterized by utilizing a collection of 1,688 GAS genomes that are representative of the global GAS population. Sequence variations were examined with multiple alignments, and the expression of all core Mga regulon genes was examined by quantitative reverse transcription-PCR in a representative strain collection. In 85.2% of the sampled genomes, the Mga locus contained genes encoding Mga, Mrp, M, Enn, and C5a peptidase proteins. These isolates account for 53% of global infections. Only 9.1% of genomes did not contain either an mrp or an enn gene. The pairwise identity within Enn (68.6%) and Mrp (83.2%) protein sequences was higher than within M proteins (44.7%). Gene expression varied between strains tested, but high expression was recorded for all genes in at least one strain. Previous nomenclature issues were clarified with molecular gene definitions. Our findings support a shift in focus in the GAS research field to further consider the role of Mrp and Enn in virulence and vaccine development.IMPORTANCE While the GAS M protein has been the leading vaccine target for decades, the bacteria encode many other virulence factors of interest for vaccine development. In this work, we show that emm-like genes are encoded in a remarkable majority of GAS genomes and expressed at a level similar to that for the emm gene. In collaboration with the U.S. Centers for Disease Control, we developed molecular definitions of the different emm and emm-like gene families. This clarification should abrogate mistyping of strains, especially in the area of whole-genome typing. We have also updated the emm-typing collection by removing emm-like gene se, SCOPUS: ar.j, info:eu-repo/semantics/published
- Published
- 2020
44. Analysis of Global Collection of Group A Streptococcus Genomes Reveals that the Majority Encode a Trio of M and M-Like Proteins
- Author
-
Frost, Hannah, Davies, Mark, Delforge, Valerie, Lakhloufi, Dalila, Sanderson-Smith, Martina L, Srinivasan, Velusamy, Steer, Andrew, Walker, Mark, Beall, Bernard, Botteaux, Anne, Smeesters, Pierre, Frost, Hannah, Davies, Mark, Delforge, Valerie, Lakhloufi, Dalila, Sanderson-Smith, Martina L, Srinivasan, Velusamy, Steer, Andrew, Walker, Mark, Beall, Bernard, Botteaux, Anne, and Smeesters, Pierre
- Abstract
Copyright 2020 Frost et al. The core Mga (multiple gene activator) regulon of group A Streptococcus (GAS) contains genes encoding proteins involved in adhesion and immune evasion. While all GAS genomes contain genes for Mga and C5a peptidase, the intervening genes encoding M and M-like proteins vary between strains. The genetic make-up of the Mga regulon of GAS was characterized by utilizing a collection of 1,688 GAS genomes that are representative of the global GAS population. Sequence variations were examined with multiple alignments, and the expression of all core Mga regulon genes was examined by quantitative reverse transcription-PCR in a representative strain collection. In 85.2% of the sampled genomes, the Mga locus contained genes encoding Mga, Mrp, M, Enn, and C5a peptidase proteins. These isolates account for 53% of global infections. Only 9.1% of genomes did not contain either an mrp or an enn gene. The pairwise identity within Enn (68.6%) and Mrp (83.2%) protein sequences was higher than within M proteins (44.7%). Gene expression varied between strains tested, but high expression was recorded for all genes in at least one strain. Previous nomenclature issues were clarified with molecular gene definitions. Our findings support a shift in focus in the GAS research field to further consider the role of Mrp and Enn in virulence and vaccine development.IMPORTANCE While the GAS M protein has been the leading vaccine target for decades, the bacteria encode many other virulence factors of interest for vaccine development. In this work, we show that emm-like genes are encoded in a remarkable majority of GAS genomes and expressed at a level similar to that for the emm gene. In collaboration with the U.S. Centers for Disease Control, we developed molecular definitions of the different emm and emm-like gene families. This clarification should abrogate mistyping of strains, especially in the area of whole-genome typing. We have also updated the emm-typing collection
- Published
- 2020
45. Analysis of Global Collection of Group A Streptococcus Genomes Reveals that the Majority Encode a Trio of M and M-Like Proteins
- Author
-
Frost, Hannah R., primary, Davies, Mark R., additional, Delforge, Valérie, additional, Lakhloufi, Dalila, additional, Sanderson-Smith, Martina, additional, Srinivasan, Velusamy, additional, Steer, Andrew C., additional, Walker, Mark J., additional, Beall, Bernard, additional, Botteaux, Anne, additional, and Smeesters, Pierre R., additional
- Published
- 2020
- Full Text
- View/download PDF
46. Electrochemical behavior and surface characterization of dental materials in artificial salivary
- Author
-
Lakhloufi, S., primary, Labjar, H., additional, Hamdouni, Y. El, additional, Bouhouche, I., additional, Dahrouch, A., additional, Serghini-Idriissi, M., additional, Lotfi, El.M., additional, Mahi, M. El, additional, Yamani, A. El, additional, Hajjaji, S. El, additional, and Labjar, N., additional
- Published
- 2020
- Full Text
- View/download PDF
47. Multiple proteins arising from a single gene: The role of the Spa33 variants in Shigella T3SS regulation
- Author
-
Pierre R. Smeesters, Dalila Lakhloufi, Virginie Imbault, Anne Botteaux, Mahendar Kadari, Valérie Delforge, and David Communi
- Subjects
lcsh:QR1-502 ,Biotechnologie ,Codon, Initiator ,Microbiology ,lcsh:Microbiology ,Type three secretion system ,Shigella flexneri ,type 3 secretion system ,Bacterial Proteins ,Extracellular ,Type III Secretion Systems ,Secretion ,secretion regulation ,Host cell membrane ,Virulence ,Chemistry ,Effector ,bacterial virulence ,pathogenesis ,Original Articles ,Translocon ,Cell biology ,Gene Expression Regulation ,Cytoplasm ,Mutation ,Original Article ,Shigella ,Signal transduction ,Bacterial Outer Membrane Proteins ,Protein Binding - Abstract
Shigella invasion and dissemination in intestinal epithelial cells relies on a type 3 secretion system (T3SS), which mediates translocation of virulence proteins into host cells. T3SSs are composed of three major parts: an extracellular needle, a basal body, and a cytoplasmic complex. Three categories of proteins are hierarchically secreted: (a) the needle components, (b) the translocator proteins which form a pore (translocon) inside the host cell membrane and (c) the effectors interfering with the host cell signaling pathways. In the absence of host cell contact, the T3SS is maintained in an “off” state by the presence of a tip complex. Secretion is activated by host cell contact which allows the release of a gatekeeper protein called MxiC. In this work, we have investigated the role of Spa33, a component of the cytoplasmic complex, in the regulation of secretion. The spa33 gene encodes a 33-kDa protein and a smaller fragment of 12 kDa (Spa33C) which are both essential components of the cytoplasmic complex. We have shown that the spa33 gene gives rise to 5 fragments of various sizes. Among them, three are necessary for T3SS. Interestingly, we have shown that Spa33 is implicated in the regulation of secretion. Indeed, the mutation of a single residue in Spa33 induces an effector mutant phenotype, in which MxiC is sequestered. Moreover, we have shown a direct interaction between Spa33 and MxiC., SCOPUS: ar.j, info:eu-repo/semantics/published
- Published
- 2019
48. La educación patrimonial en la asignatura de Historia
- Author
-
Balouati Lakhloufi, Selim and González González, José Manuel
- Abstract
La educación patrimonial puede obtener su espacio dentro de la asignatura de historia debido al carácter interdisciplinar de esta materia. En este trabajo se realizará un análisis y estudio sobre la integración de la educación patrimonial en la materia de historia en el aula, así como del estado de la educación patrimonial en el marco legal educativo. Se analizarán los beneficios que puede aportar a los estudiantes de la asignatura de historia, así como las posibles metodologías para llevarlas a cabo citando a los autores más relevantes de la educación patrimonial.
- Published
- 2019
49. Multiple proteins arising from a single gene: The role of the Spa33 variants in Shigella T3SS regulation
- Author
-
Kadari, M, Lakhloufi, D, Delforge, V, Imbault, V, Communi, D, Smeesters, P, Botteaux, A, Kadari, M, Lakhloufi, D, Delforge, V, Imbault, V, Communi, D, Smeesters, P, and Botteaux, A
- Abstract
Shigella invasion and dissemination in intestinal epithelial cells relies on a type 3 secretion system (T3SS), which mediates translocation of virulence proteins into host cells. T3SSs are composed of three major parts: an extracellular needle, a basal body, and a cytoplasmic complex. Three categories of proteins are hierarchically secreted: (a) the needle components, (b) the translocator proteins which form a pore (translocon) inside the host cell membrane and (c) the effectors interfering with the host cell signaling pathways. In the absence of host cell contact, the T3SS is maintained in an "off" state by the presence of a tip complex. Secretion is activated by host cell contact which allows the release of a gatekeeper protein called MxiC. In this work, we have investigated the role of Spa33, a component of the cytoplasmic complex, in the regulation of secretion. The spa33 gene encodes a 33-kDa protein and a smaller fragment of 12 kDa (Spa33C ) which are both essential components of the cytoplasmic complex. We have shown that the spa33 gene gives rise to 5 fragments of various sizes. Among them, three are necessary for T3SS. Interestingly, we have shown that Spa33 is implicated in the regulation of secretion. Indeed, the mutation of a single residue in Spa33 induces an effector mutant phenotype, in which MxiC is sequestered. Moreover, we have shown a direct interaction between Spa33 and MxiC.
- Published
- 2019
50. Multiple proteins arising from a single gene: The role of the Spa33 variants in Shigella T3SS regulation
- Author
-
Kadari, Mahendar, Lakhloufi, Dalila, Delforge, Valérie, Imbault, Virginie, Communi, David, Smeesters, Pierre, Botteaux, Anne, Kadari, Mahendar, Lakhloufi, Dalila, Delforge, Valérie, Imbault, Virginie, Communi, David, Smeesters, Pierre, and Botteaux, Anne
- Abstract
Shigella invasion and dissemination in intestinal epithelial cells relies on a type 3 secretion system (T3SS), which mediates translocation of virulence proteins into host cells. T3SSs are composed of three major parts: an extracellular needle, a basal body, and a cytoplasmic complex. Three categories of proteins are hierarchically secreted: (a) the needle components, (b) the translocator proteins which form a pore (translocon) inside the host cell membrane and (c) the effectors interfering with the host cell signaling pathways. In the absence of host cell contact, the T3SS is maintained in an “off” state by the presence of a tip complex. Secretion is activated by host cell contact which allows the release of a gatekeeper protein called MxiC. In this work, we have investigated the role of Spa33, a component of the cytoplasmic complex, in the regulation of secretion. The spa33 gene encodes a 33-kDa protein and a smaller fragment of 12 kDa (Spa33C) which are both essential components of the cytoplasmic complex. We have shown that the spa33 gene gives rise to 5 fragments of various sizes. Among them, three are necessary for T3SS. Interestingly, we have shown that Spa33 is implicated in the regulation of secretion. Indeed, the mutation of a single residue in Spa33 induces an effector mutant phenotype, in which MxiC is sequestered. Moreover, we have shown a direct interaction between Spa33 and MxiC., SCOPUS: ar.j, info:eu-repo/semantics/published
- Published
- 2019
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