A. Touati - Academia.edu (original) (raw)

Papers by A. Touati

Letters in Applied Microbiology, 2021

Although SARS-CoV-2 is primarily an airborne risk, the COVID-19 pandemic also highlighted the nee... more Although SARS-CoV-2 is primarily an airborne risk, the COVID-19 pandemic also highlighted the need for self-disinfection surfaces that could withstand the demand of high occupant densities characteristic of public transportation systems. The aim of this study was to evaluate the durability and antiviral activity of a copper film deployed for 90 days in two high touch locations within an active metropolitan bus and railcar. The antiviral efficacy of this copper film after being deployed in transit vehicles for 90 days (deployed copper film) was then compared to new (unused) copper film to determine if frequent touches and cleaning protocols could decrease the efficacy of the copper films. Deployed copper film, new copper film, and aluminium foil (positive control) coupons were inoculated with ~1 × 106 MS2 virus particles, allowed a contact time of either 5- or 10-min, and analysed for residual viral infectiousness. On both new and deployed copper films, MS2 was completely inactivated...

African Review of Physics, 2009

Silicon nitride (SiN) film deposited by a plasma-enhanced chemical vapour deposition (PECVD) is w... more Silicon nitride (SiN) film deposited by a plasma-enhanced chemical vapour deposition (PECVD) is widely used in photovoltaic industry as an anti-reflection coating (ARC) [1] and emitter passivity [2] [3]. As a third advantage, the large amount of hydrogen resulting from plasma gases dissociation and incorporated in the SiN film can be driven into the solar cell during deposition and the contact firing step, leading to excellent bulk passivity for multi-crystalline silicon solar cells. For an efficient ARC, the SiN layer is designed for an optimum wavelength of 580 to 680 nm corresponding to a layer thickness between 70 and 80 nm and a refractive index n around 2.0 [4]. In this work, we intend to determine the deposition parameters leading to optimal optical characteristics of SiN film for photovoltaic application and then evaluate its effect on electrical parameters of solar cells. The deposition was performed in an industrial direct PECVD using a gas mixture of SiH4 and NH3. The stu...

M. K. Ahmed1, A. M. Hashem2, A. F. Mostafa3, H. M. Shams4. 1Biochemistry Department, Faculty of S... more M. K. Ahmed1, A. M. Hashem2, A. F. Mostafa3, H. M. Shams4. 1Biochemistry Department, Faculty of Science, Ain Shams University, Cairo, Egypt, 2Infectious disease and endemic hepatogastroentrology department, Faculty of medicine, Cairo University, Cairo, Egypt, 3Pathology Department, Faculty of Medicine, Menoufia University, Menoufia, Egypt, 4Clinical and Chemical Pathology Department, National Cancer Institute, Cairo, Egypt, Cairo, Egypt

Journal of Clinical Microbiology, 2021

We evaluated the utility of the commercial Allplex genital ulcer real-time PCR multiplex assay fo... more We evaluated the utility of the commercial Allplex genital ulcer real-time PCR multiplex assay for detecting Treponema pallidum (TPA), herpes simplex virus 1 (HSV-1) and 2 (HSV-2), and Chlamydia trachomatis serovar L (lymphogranuloma venereum [LGV]) DNA in mucosal and genital ulcers in the context of suspected syphilis. In total, 374 documented genital and mucosal ulcers from patients with and without syphilis presenting at several sexually transmitted infection (STI) centers in France from October 2010 to December 2016 were analyzed at the National Reference Center (CNR) for Bacterial STIs at Cochin Hospital in Paris. TPA detection results were compared with the final diagnosis based on a combination of clinical examination, serological results, and in-house nested PCR (nPCR).

Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases, 2016

The French Reference Centre for chlamydiae uses two real-time PCRs targeting the pmpH gene of Chl... more The French Reference Centre for chlamydiae uses two real-time PCRs targeting the pmpH gene of Chlamydia trachomatis to differentiate between L strains and variant L2b, responsible for a lymphogranuloma venereum outbreak in Europe. We compared the results obtained for 122 L2b C. trachomatis-positive specimens, using the two real-time PCRs, with the sequencing of the ompA gene. Only 91 specimens were confirmed as L2b. Our results demonstrate that the lymphogranuloma venereum outbreak is no longer dominated by the variant L2b, and that many L-positive specimens were misidentified as L2b with the method used, which raises the question of its specificity.

AIP Conference Proceedings, 2003

It is often thought that unrepaired or misrepaired complex DNA double-strand breaks are responsib... more It is often thought that unrepaired or misrepaired complex DNA double-strand breaks are responsible for cell inactivation and chromosomal aberrations. Here the role of inner-shell (core) ionizations in DNA atoms is studied. Ultrasoft X-rays from LURE synchrotron radiation have been used to produce core events which mimic the ones induced by ionizing radiations. By tuning the X-ray energy below and above the carbon K-threshold, it is possible to achieve a two-fold increase of the number of core-ionizations in DNA for a same dose in cell. Cell survival, DNA double-strand breaks and chromosomal aberrations have thus been studied, at three energies iso-attenuated in biological samples:~ 250, 350 and 800 eV. The relative biological efficiencies of a given dose in cells to induce cell inactivation and chromosome aberrations appear governed by the yields of core events in DNA. On the other hand, the lethal and DNA-breaking efficiencies of core events in DNA appear strongly correlated.

Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases, 2015

MATEC Web of Conferences, 2014

This work aims to study a cascade of two BOOST converters. First, a non-linear model of the whole... more This work aims to study a cascade of two BOOST converters. First, a non-linear model of the whole controlled system is developed. Then, a robust non-linear controller of currents is synthesized using a backstepping design technique. A formal analysis based on Lyapunov stability and average theory is developed to describe the control currents loops performances. A classical PI controller is used for the voltages loops. The study of the stability of the system will also be discussed. Simulated results are displayed to validate the feasibility and the effectiveness of the proposed strategy.

Journal de Thérapie Comportementale et Cognitive, 2004

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1985

ABSTRACT

Journal de Chimie Physique et de Physico-Chimie Biologique, 1999

ABSTRACT

Physical Review A, 1981

The probability of double-K-vacancy production accompanying internal conversion in three differen... more The probability of double-K-vacancy production accompanying internal conversion in three different atoms. In (Z=49), Ba (Z=56), and T1 (Z=81) has been measured in coincidence experiments. The comparison of our experimental results with various theoretical approaches exhibits the importance of correlation effects between the two K electrons.

Pathologie Biologie, 2007

La production de slime, principal facteur de virulence de Staphylococcus epidermidis impliqué dan... more La production de slime, principal facteur de virulence de Staphylococcus epidermidis impliqué dans les infections liées aux cathéters veineux centraux, est codée par l'opéron icaADBC dont l'expression est sujette à une variation de phase. La transposition réversible de l'élément IS256 au niveau de cet opéron est l'un des mécanismes les plus important de cette variation. Notre étude a comparé 28 souches de S. epidermidis responsables d'infections liées aux cathéters à 28 souches de portage nasal concernant la détection de slime sur milieu rouge Congo, la recherche des gènes ica et de l'élément IS256 par PCR. L'opéron ica a été présent parmi toutes les souches productrices de slime, et absent parmi les souches slime négatif. Seules 79 % des souches porteuses des gènes ica ont été productrices de slime et aucune insertion de la séquence IS256 n'a été détectée dans les gènes ica. Une différence significative a été retrouvée entre souches responsables d'infection et souches de portage en termes de résistance à l'oxacilline (67,8 contre 35,7 %) et à l'ofloxacine (75 contre 35,7 %), de production de slime (64,2 contre 28,5 %), de phénotype variable (46,4 contre 7,1 %) et de présence des gènes ica (82,1 contre 35,7 %). Notre étude démontre le rôle des gènes ica, de la variabilité phénotypique de la production de biofilm et de la multirésistance aux antibiotiques comme facteurs de virulence des souches de S. epidermidis responsables d'infections liés aux cathéters ; elle confirme également la complexité et la diversité des mécanismes régulateurs intervenant au cours de la formation de biofilm.

Neurocomputing, 2015

In this paper, the problem of stability for a class of time-delay Hopfield neural networks with i... more In this paper, the problem of stability for a class of time-delay Hopfield neural networks with impulsive perturbation is investigated. The existence of a unique equilibrium point is proved by using the Arzelà-Ascoli's theorem and Rolle's theorem. Some sufficient stability criteria have proved that the uniform stability, the uniform asymptotic stability, the global asymptotic stability and the global exponential stability of the system, are derived from using the Lyapunov functional method and the linear matrix inequality approach by estimating the upper bound of the derivative of Lyapunov functional. The exponential convergence rate of the equilibrium point is also estimated. Finally, we analyse and interpret some numerical examples showing the efficiency of our theoretical results.

Photolithography allows the fabrication of a solid polymer object through polymerization of a mon... more Photolithography allows the fabrication of a solid polymer object through polymerization of a monomer resin by means of a laser source guided according to the data of computer aided design. However, one drawback of this method is the inaccuracy of the dimensions of the objects related to the shrinkage phenomenon which depends on the polymerization, on the laser flux and on the used sweeping procedure. In this paper, the deformation of an isolated voxel (elementary volume) or a voxel interacting with its neighbor is described. This simulation is based on a kinetic model that takes into account the gel effect and a model of volumetric variation due to the difference of the length of the bonds between the monomer and polymer molecules.

Renewable Energy, 2008

In this work, our aim was to determine the deposition parameters leading to optimal optical prope... more In this work, our aim was to determine the deposition parameters leading to optimal optical properties of Silicon nitride (SiN) film for photovoltaic application. The deposition was performed in an industrial pulsed direct-PECVD using a gas mixture of NH3/SiH4.After defining the optimum deposition parameters, we have chemically evaluated the film quality in BOE solution. Plasma removal of the optimized SiN

Zeitschrift f�r Wahrscheinlichkeitstheorie und Verwandte Gebiete, 1984

The thesis is a summary of surveys completed at annual construction seminars hosted by the Master... more The thesis is a summary of surveys completed at annual construction seminars hosted by the Master Builders of Iowa, Inc. by project managers and superintendents. Seven different surveys are listed regarding the preferences of each group (superintendents and managers). Surveys were conducted on the following subjects:

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 1994

... 87 (1994) 45-50 North-Holland Beam Interactions with Materials & Atom... more ... 87 (1994) 45-50 North-Holland Beam Interactions with Materials & Atoms Recent questions about the excitation mechanism at intermediate velocity L. Adoui a, M. Chabot a, A ... The nature and the origin of the so-called "saturation effect" at high exciting charge is not yet elucidated ...

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 1991

Total and partial excitation cross sections for 34 MeV/amu Kr 34t ions colliding with various tar... more Total and partial excitation cross sections for 34 MeV/amu Kr 34t ions colliding with various targets (6 I 2, < 40) have been determined from projectile X-ray measurements. The results were compared to the predictions of a method based on Schwinger's variational principle.

Letters in Applied Microbiology, 2021

Although SARS-CoV-2 is primarily an airborne risk, the COVID-19 pandemic also highlighted the nee... more Although SARS-CoV-2 is primarily an airborne risk, the COVID-19 pandemic also highlighted the need for self-disinfection surfaces that could withstand the demand of high occupant densities characteristic of public transportation systems. The aim of this study was to evaluate the durability and antiviral activity of a copper film deployed for 90 days in two high touch locations within an active metropolitan bus and railcar. The antiviral efficacy of this copper film after being deployed in transit vehicles for 90 days (deployed copper film) was then compared to new (unused) copper film to determine if frequent touches and cleaning protocols could decrease the efficacy of the copper films. Deployed copper film, new copper film, and aluminium foil (positive control) coupons were inoculated with ~1 × 106 MS2 virus particles, allowed a contact time of either 5- or 10-min, and analysed for residual viral infectiousness. On both new and deployed copper films, MS2 was completely inactivated...

African Review of Physics, 2009

Silicon nitride (SiN) film deposited by a plasma-enhanced chemical vapour deposition (PECVD) is w... more Silicon nitride (SiN) film deposited by a plasma-enhanced chemical vapour deposition (PECVD) is widely used in photovoltaic industry as an anti-reflection coating (ARC) [1] and emitter passivity [2] [3]. As a third advantage, the large amount of hydrogen resulting from plasma gases dissociation and incorporated in the SiN film can be driven into the solar cell during deposition and the contact firing step, leading to excellent bulk passivity for multi-crystalline silicon solar cells. For an efficient ARC, the SiN layer is designed for an optimum wavelength of 580 to 680 nm corresponding to a layer thickness between 70 and 80 nm and a refractive index n around 2.0 [4]. In this work, we intend to determine the deposition parameters leading to optimal optical characteristics of SiN film for photovoltaic application and then evaluate its effect on electrical parameters of solar cells. The deposition was performed in an industrial direct PECVD using a gas mixture of SiH4 and NH3. The stu...

M. K. Ahmed1, A. M. Hashem2, A. F. Mostafa3, H. M. Shams4. 1Biochemistry Department, Faculty of S... more M. K. Ahmed1, A. M. Hashem2, A. F. Mostafa3, H. M. Shams4. 1Biochemistry Department, Faculty of Science, Ain Shams University, Cairo, Egypt, 2Infectious disease and endemic hepatogastroentrology department, Faculty of medicine, Cairo University, Cairo, Egypt, 3Pathology Department, Faculty of Medicine, Menoufia University, Menoufia, Egypt, 4Clinical and Chemical Pathology Department, National Cancer Institute, Cairo, Egypt, Cairo, Egypt

Journal of Clinical Microbiology, 2021

We evaluated the utility of the commercial Allplex genital ulcer real-time PCR multiplex assay fo... more We evaluated the utility of the commercial Allplex genital ulcer real-time PCR multiplex assay for detecting Treponema pallidum (TPA), herpes simplex virus 1 (HSV-1) and 2 (HSV-2), and Chlamydia trachomatis serovar L (lymphogranuloma venereum [LGV]) DNA in mucosal and genital ulcers in the context of suspected syphilis. In total, 374 documented genital and mucosal ulcers from patients with and without syphilis presenting at several sexually transmitted infection (STI) centers in France from October 2010 to December 2016 were analyzed at the National Reference Center (CNR) for Bacterial STIs at Cochin Hospital in Paris. TPA detection results were compared with the final diagnosis based on a combination of clinical examination, serological results, and in-house nested PCR (nPCR).

Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases, 2016

The French Reference Centre for chlamydiae uses two real-time PCRs targeting the pmpH gene of Chl... more The French Reference Centre for chlamydiae uses two real-time PCRs targeting the pmpH gene of Chlamydia trachomatis to differentiate between L strains and variant L2b, responsible for a lymphogranuloma venereum outbreak in Europe. We compared the results obtained for 122 L2b C. trachomatis-positive specimens, using the two real-time PCRs, with the sequencing of the ompA gene. Only 91 specimens were confirmed as L2b. Our results demonstrate that the lymphogranuloma venereum outbreak is no longer dominated by the variant L2b, and that many L-positive specimens were misidentified as L2b with the method used, which raises the question of its specificity.

AIP Conference Proceedings, 2003

It is often thought that unrepaired or misrepaired complex DNA double-strand breaks are responsib... more It is often thought that unrepaired or misrepaired complex DNA double-strand breaks are responsible for cell inactivation and chromosomal aberrations. Here the role of inner-shell (core) ionizations in DNA atoms is studied. Ultrasoft X-rays from LURE synchrotron radiation have been used to produce core events which mimic the ones induced by ionizing radiations. By tuning the X-ray energy below and above the carbon K-threshold, it is possible to achieve a two-fold increase of the number of core-ionizations in DNA for a same dose in cell. Cell survival, DNA double-strand breaks and chromosomal aberrations have thus been studied, at three energies iso-attenuated in biological samples:~ 250, 350 and 800 eV. The relative biological efficiencies of a given dose in cells to induce cell inactivation and chromosome aberrations appear governed by the yields of core events in DNA. On the other hand, the lethal and DNA-breaking efficiencies of core events in DNA appear strongly correlated.

Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases, 2015

MATEC Web of Conferences, 2014

This work aims to study a cascade of two BOOST converters. First, a non-linear model of the whole... more This work aims to study a cascade of two BOOST converters. First, a non-linear model of the whole controlled system is developed. Then, a robust non-linear controller of currents is synthesized using a backstepping design technique. A formal analysis based on Lyapunov stability and average theory is developed to describe the control currents loops performances. A classical PI controller is used for the voltages loops. The study of the stability of the system will also be discussed. Simulated results are displayed to validate the feasibility and the effectiveness of the proposed strategy.

Journal de Thérapie Comportementale et Cognitive, 2004

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1985

ABSTRACT

Journal de Chimie Physique et de Physico-Chimie Biologique, 1999

ABSTRACT

Physical Review A, 1981

The probability of double-K-vacancy production accompanying internal conversion in three differen... more The probability of double-K-vacancy production accompanying internal conversion in three different atoms. In (Z=49), Ba (Z=56), and T1 (Z=81) has been measured in coincidence experiments. The comparison of our experimental results with various theoretical approaches exhibits the importance of correlation effects between the two K electrons.

Pathologie Biologie, 2007

La production de slime, principal facteur de virulence de Staphylococcus epidermidis impliqué dan... more La production de slime, principal facteur de virulence de Staphylococcus epidermidis impliqué dans les infections liées aux cathéters veineux centraux, est codée par l'opéron icaADBC dont l'expression est sujette à une variation de phase. La transposition réversible de l'élément IS256 au niveau de cet opéron est l'un des mécanismes les plus important de cette variation. Notre étude a comparé 28 souches de S. epidermidis responsables d'infections liées aux cathéters à 28 souches de portage nasal concernant la détection de slime sur milieu rouge Congo, la recherche des gènes ica et de l'élément IS256 par PCR. L'opéron ica a été présent parmi toutes les souches productrices de slime, et absent parmi les souches slime négatif. Seules 79 % des souches porteuses des gènes ica ont été productrices de slime et aucune insertion de la séquence IS256 n'a été détectée dans les gènes ica. Une différence significative a été retrouvée entre souches responsables d'infection et souches de portage en termes de résistance à l'oxacilline (67,8 contre 35,7 %) et à l'ofloxacine (75 contre 35,7 %), de production de slime (64,2 contre 28,5 %), de phénotype variable (46,4 contre 7,1 %) et de présence des gènes ica (82,1 contre 35,7 %). Notre étude démontre le rôle des gènes ica, de la variabilité phénotypique de la production de biofilm et de la multirésistance aux antibiotiques comme facteurs de virulence des souches de S. epidermidis responsables d'infections liés aux cathéters ; elle confirme également la complexité et la diversité des mécanismes régulateurs intervenant au cours de la formation de biofilm.

Neurocomputing, 2015

In this paper, the problem of stability for a class of time-delay Hopfield neural networks with i... more In this paper, the problem of stability for a class of time-delay Hopfield neural networks with impulsive perturbation is investigated. The existence of a unique equilibrium point is proved by using the Arzelà-Ascoli's theorem and Rolle's theorem. Some sufficient stability criteria have proved that the uniform stability, the uniform asymptotic stability, the global asymptotic stability and the global exponential stability of the system, are derived from using the Lyapunov functional method and the linear matrix inequality approach by estimating the upper bound of the derivative of Lyapunov functional. The exponential convergence rate of the equilibrium point is also estimated. Finally, we analyse and interpret some numerical examples showing the efficiency of our theoretical results.

Photolithography allows the fabrication of a solid polymer object through polymerization of a mon... more Photolithography allows the fabrication of a solid polymer object through polymerization of a monomer resin by means of a laser source guided according to the data of computer aided design. However, one drawback of this method is the inaccuracy of the dimensions of the objects related to the shrinkage phenomenon which depends on the polymerization, on the laser flux and on the used sweeping procedure. In this paper, the deformation of an isolated voxel (elementary volume) or a voxel interacting with its neighbor is described. This simulation is based on a kinetic model that takes into account the gel effect and a model of volumetric variation due to the difference of the length of the bonds between the monomer and polymer molecules.

Renewable Energy, 2008

In this work, our aim was to determine the deposition parameters leading to optimal optical prope... more In this work, our aim was to determine the deposition parameters leading to optimal optical properties of Silicon nitride (SiN) film for photovoltaic application. The deposition was performed in an industrial pulsed direct-PECVD using a gas mixture of NH3/SiH4.After defining the optimum deposition parameters, we have chemically evaluated the film quality in BOE solution. Plasma removal of the optimized SiN

Zeitschrift f�r Wahrscheinlichkeitstheorie und Verwandte Gebiete, 1984

The thesis is a summary of surveys completed at annual construction seminars hosted by the Master... more The thesis is a summary of surveys completed at annual construction seminars hosted by the Master Builders of Iowa, Inc. by project managers and superintendents. Seven different surveys are listed regarding the preferences of each group (superintendents and managers). Surveys were conducted on the following subjects:

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 1994

... 87 (1994) 45-50 North-Holland Beam Interactions with Materials &amp;amp;amp;amp;amp; Atom... more ... 87 (1994) 45-50 North-Holland Beam Interactions with Materials &amp;amp;amp;amp;amp; Atoms Recent questions about the excitation mechanism at intermediate velocity L. Adoui a, M. Chabot a, A ... The nature and the origin of the so-called &amp;amp;amp;amp;quot;saturation effect&amp;amp;amp;amp;quot; at high exciting charge is not yet elucidated ...

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 1991

Total and partial excitation cross sections for 34 MeV/amu Kr 34t ions colliding with various tar... more Total and partial excitation cross sections for 34 MeV/amu Kr 34t ions colliding with various targets (6 I 2, < 40) have been determined from projectile X-ray measurements. The results were compared to the predictions of a method based on Schwinger's variational principle.