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The repair of abdominal hernias with prosthetic mesh can significantly reduce the risk of hernia recurrence. A new type of hernia implants combines monofilaments, Polypropylene (PP) and a biobased and natural slowly bioabsorbable polymer, Poly-L-Lactic Acid (PLLA). The partially (60%) resorbable PLLA/PP and PP meshes manufactured by COUSIN Surgery are 4DVentral® and Biomesh P1®. The contribution of PLLA in regulated inflammatory response and in enhancing abdominal repair remains unknown. Inflammation has a functional role during tissue regeneration process. An abnormal macrophage response characterized by an uncontrolled release of pro-inflammatory cytokines, chemokines, and tissue-degrading enzymes has been shown to be responsible for postoperative complications. In contrast, the angiogenic and tissue remodeling activities of the alternative anti-inflammatory M2 macrophages have potential use in tissue regenerative. Here, the characterization of the inflammatory response of human macrophages in vitro regarding 4DVentral® compared to Biomesh P1® was performed. Human monocytic THP-1 cells were differentiated into macrophages and polarized in M1 macrophages by incubation with IFN-γ and LPS or not (M0 macrophages). We found that 4DVentral® induced higher secretion of anti-inflammatory cytokines (IL-10 and Il1-RA) compared to PP Mesh in M0 macrophages. Interestingly, the secretion of pro-inflammatory cytokine IL-6 in M1 macrophages was dramatically reduced in the presence of 4DVentral® mesh compared to PP Biomesh P1®. However, the secretion of IL-10 was significantly increased with 4DVentral®. The composite PLLA/PP monofilament 4DVentral® positively drives human macrophages to an anti-inflammatory profile, resolving inflammation and promoting tissue repair.

The effect of gamma-rays on structural, optical and photocatalytic properties of TiO2 nanoparticles under controlled atmospheres are studied to further improve photocatalytic performance. The sol–gel TiO2 powders were deposited with spin-coating technique, annealed at 500°C then finally irradiated by gamma-rays. The structural and optical characteristics of samples were investigated by Fourier transform infrared spectroscopy, x-ray diffraction and UV-visible spectroscopy (UV). The time-dependent density functional theory (TD-DFT) calculation are used to determine ground geometries and electronic structures of TiO2 nanostructures. DFT calculations present an excellent conformity with experimental results, and a high anisotropy in stretched thermal and electrical conductivity TiO2 nanostructures was found. Structural and optical results show that gamma radiation did not change the crystallinity of TiO2 nanostructures and leads to an optical band gap reduction to 3.039 eV. The gamma radiation effect on photocatalytic performance was investigated by methylene blue degradation as a typical pollutant. Gamma radiation has been discovered to improve considerably the degradation of pollutants compared with unirradiated TiO2.

In the framework of the ICERR (International CEntres based on Research Reactors) project, the effect of neutron/gamma irradiation on material has been studied. In this work, we investigate the mixed neutron/gamma irradiation effects on the optical properties of epoxy resin polymers. Photoluminescence (PL) measurements are used in epoxy resin films irradiated in the dose range from 0 to 900 Gy. For more information about the carriers dynamics, we studied their activation energy and phononic processes through the analysis of the PL spectrum evolution as a function of temperature. Mostly, materials irradiation studies by ionizing sources show a generation of defects and subsequently lead to the damage and degradation on the different properties. In this study we have shown an advantage of neutron/gamma irradiation, it is the improvement of the luminescence properties. The 500 Gy dose has the highest quantum yield at low temperature. But the 600 Gy dose shows the highest yield at room temperature. For...

An investigation of the dielectric dispersion, electrical properties, scaling behavior and optical defects of Ca0.67La0.22□0.11Ti(1−x)CrxO3−δ (CLT(1−x)Crx) with x = 0 and x = 0.1 compositions is presented. The square in the formula is attributed to a vacancy in A-site. Relaxation phenomena were studied with dielectric and modulus formalism, while, the conductivity mechanism was investigated using electrical conductivity. A high permittivity of around 104, low dielectric loss and low electrical conductivity of around 10−3 S cm−1 for Ca0.67La0.22TiO3 (CLT) was observed. These values make this composition interesting for microelectric applications. A comparison between the Z′′ and M′′ indicated that the short-range carrier motion dominates at low temperature and becomes less localized at high temperature. The optical defects of CLT and Ca0.67La0.22Ti0.9Cr0.1O3 (CLT0.9Cr0.1) were studied by electron paramagnetic resonance (EPR) spectroscopy. The results suggest the formation of a [TiO6]9− center, a (Ti3+–VO) center, and dipole defect for CLT compound and Cr3+–VO center defect for CLT0.9Cr0.1 compound. These defects are the source of the in-gap electron traps, which improve the optical properties of CLT(1−x)Crx and hence make it an interesting optical material for different applications.

This paper highlights some physical investigations on GO-doped ZnO thin films synthesized using zinc acetate dehydrate isopropyl alcohol and graphene oxide (GO) as doping element in a starting solution using a mini-spray pyrolysis process. These films, with thicknesses less than 400 nm, crystallize in hexagonal wurtzite structure with a preferential orientation according to (002) direction. The morphological characterization revealed a good homogeneity at the surface with good dispersion of graphene nanoparticles over the entire surface, especially for 2% GO doping. The refractive index and thickness of ZnO:GO thin films have been calculated using the envelope method. A decrease in the refractive index with doping was observed which indicates an increase of free carriers. In addition, band gap and Urbach energies were also deducted from the absorption coefficient. Indeed, this layer provides an increase in the dielectric constant e2 in the IR range, which is a proof of creating free electrons. Finally, the 2% GO doping gives the best optoelectrical properties of ZnO thin films which can be used in a forthcoming application for future optoelectronics.

Single crystals of tetra-(benzylammonium) dihydrogen decavanadate dihydrate, (C7H10N)4[H2V10O28].2H2O, were grown in an aqueous solution at room temperature. The decavanadate compound was characterized by IR spectroscopy and X-ray powder diffraction. This compound crystallizes in the triclinic system, space group P-1, with a = 10.119(5) A, b = 10.284(3) A, c = 13.945(6) A, α = 69.87(3), β= 72.47(4), γ = 61.15(3), V = 1177.24(1) A3 and Z=1. The formula unit of decavanadate compound consists of one dihydrogen decavanadate anion [H2V10O28]4−, four organic cations (C7H10N)+ and two water molecules. The three-dimensional Hirshfeld surface (3D-HS) and their relative two-dimensional fingerprint plots (2D-FP) of (C7H10N)4[H2V10O28].2H2O compound, revealed that the structure is dominated by H…O/O…H (52.5 %) and H…H (22 %) contacts. Interestingly, when tested on MDA-MB231 triple negative human breast cancer cells, the (C7H10N)4[H2V10O28].2H2O compound inhibits their proliferation and migration at a micromolar range, suggesting its potential use as therapeutic molecule against breast cancer.

International centers based on research reactors (ICERR) project supported by IAEA, offers training and research in the application of advanced nuclear reactor technology. In this context of the project, alanine dosimeters were irradiated under mixed neutron/gamma irradiation in the core of the MINERVE research reactor at the CEA Cadarache. The integrated dose of the alanine was measured by electron spin resonance spectrometry with reference to an absorbed dose in water from a 60Co gamma-ray beam. Neutron and gamma dose components were calculated using the MCNP code. The neutron dose and relative effectiveness ( R E n ) for neutrons was evaluated using FLUKA code and Track Structure Theory (TST) formulations of alanine response towards irradiations with ions produced by neutron interactions with alanine. R E n values were found to be between 0.516 and 0.538. The measured dose was compared to the calculation results. The best agreement between the alanine integral measurements and model predictions (0.4%) was obtained by using the Cucinotta alanine detector response model.

Nickel-doped poly vinyl alcohol (PVA) films were developed for potential application in industrial sectors like radiation processing. We report in this paper the results of an experimental investigation of 60Co source γ-radiation effect on colorimetric, structural and morphological properties of PVA films doped with 0.5% Ni2+ ions (PVA/Ni2+). The PVA/Ni2+ films were irradiated by different gamma-radiation doses varying from 5 to 100 kGy. Color modification of films were studied using L∗, a∗ and b∗ color space measurements as function of the γ-dose and post-irradiation time. The visual change in all samples was verified by microstructure analysis, Fourier transforms infrared (FTIR) spectroscopy, X-Rays diffraction (XRD) and scanning electron microscopy (SEM). The color space exhibited a linear dose response at a dose ranging from 5 to 50 kGy, and then it reached saturation for higher γ-doses. The calculated color changes (ΔE) show a linear dose response relationship from 9.90 to 115.02 in the dose range from 0 to 50 kGy. It showed also the activation of stable color centers. The variability of the color change did not exceed 3% during 80 h (h) post-irradiation. Furthermore, the microstructure analysis evidenced that the color modification due to the optical activation of nickel-oxide (NiO) color center were obtained by complexing Ni2+ ions in irradiated PVA films. The obtained results inspire the possibility to use PVA films for the control process in industrial radiation facilities in dose range 5–50 kGy.

This work focuses on the impact of Bismuth (Bi) solution treatment on the optical properties of p-type porous silicon prepared by electrochemical anodization. Bi-layers of variable thickness are incorporated in porous silicon via a dip coating technique. The changes in the structural and optical properties of Bi (III)/PS nanostructures are monitored by Atomic Force Microscopy, Fourier transform infrared measurements and photoluminescence spectroscopy. These analyses highlight a relevant impact of the deposition process, which modifies the intrinsic properties of the porous silicon by the incorporation of Bi (III) in its pores. It is found that ultra-thin films of bismuth oxide formed after a heat treatment in air at 400 °C and deposited on PS samples leads to its stability as well as to passivating its dangling bands. For thicknesses ranging from 6 to 20 nm, the photoluminescence property in the visible region of Bi/PS nanostructures has been improved. This may be of interest for various optoelectronic applications.

In this work, we investigate the gamma radiation effects on the optical properties of δ-Si-doping InGaAs/GaAs/AlGaAs High Electron Mobility Transistors (HEMT) grown by molecular beam epitaxy on (100) oriented GaAs substrates. Photoluminescence measurements are used to determine electron and hole relaxation process in the InGaAs/GaAs/AlGaAs (δ-Si) HEMTs. For more information about the carriers dynamics in the examined structures, we studied their interactions with the crystal lattice, defects and thermal activation through the analysis of the PL spectrum evolution depending on the temperature. With a treatment of 10 KGy the PL measurements prove a stability in activation energy and Debye temperature and a strongly affected for phonons contributions.

This work covers for the first time the protocol of the preparation of nominal composition La0.8Sr0.2GaO3 by the sol–gel method using the citric acid. The structural and the optical properties were investigated, by X-ray diffraction (XRD), Fourier Transform infrared Spectroscopy (FT-IR) and Photoluminescence Spectroscopy (PL) techniques, respectively. The Rietveld refinement, from the X-ray diffraction patterns, showed the presence of La0.63Sr0.21Ga0.95O2.68 perovskite as a major phase which crystallizes in an Hexagonal structure and the appearance of minor impurity phase identified as Gallium Lanthanum Oxide (La4Ga2O9) belonging to a Monoclinic structure. Two peaks indicating blue photoluminescence emission were observed at room temperature. One emission was related to secondary phase and the other was assigned rather to the oxygen deficiency in perovskite structure, leading to the formation of intermediary energy levels in the band gap.

The purpose of this work is to study the effect of mixed neutron–gamma radiation (MNGR) on structural, optical and paramagnetic properties on epoxy resin nanostructure thin films [ER]NSTF. These films were prepared and irradiated in the nuclear reactor with dose range between 100 and 900 Gy. After exposure to MNGR, FT-IR results demonstrated the broad ν(OH) and ν(C=O) band to increase with increase in radiation dose, while the ν(C–H) band decreased with increase in radiation dose. This is due to the formation of chain stretch, bending and scission/cross-linking through MNGR that lead to a decrease in the crystallinity region contained within the [ER]NSTF. XRD data confirm these results and show that the crystalline phase was destroyed by MNGR irradiation. PL is used to determine the fundamental transition and defects transitions in [ER]NSTF at 300 K. It was found that MNGR leads to significant enhancement of the luminescence properties. Samples of [ER]NSTF irradiated with 600 Gy dose presented the highest response. Therefore, EPR results confirmed that MNGR induces the paramagnetic center’s formation of the [ER]NSTF whose concentration varies differently.

Zoonotic visceral leishmaniasis is a common vector-borne systemic disease caused by Leishmania infantum (Kinetoplastida: Trypanosomatidae). In Morocco the situation is complex: many sandfly species have been collected in areas in which the disease is endemic, but only Phlebotomus ariasi, Phlebotomus perniciosus and Phlebotomus longicuspis (Diptera: Psychodidae) have been confirmed to have vectorial roles. The objective of the present study was to ascertain the potential distribution of L. infantum and its vectors in Morocco, using ecological niche modelling. Vector records were obtained from field collections of the Laboratory team and from previously published entomological observations. Epidemiological data for L. infantum modelling were obtained from Moroccan Ministry of Health reports. The jackknife test indicated that the bioclimatic variables with the greatest influence on model development for all species were annual precipitation and precipitation in the driest quarter of the year. MaxEnt model representations for sandfly species that act as vectors of L. infantum showed the widespread geographic distribution of these species in Morocco, specifically in northern and central Morocco, where foci of visceral leishmaniasis are found. The ecological niche modelling points out areas in which the probability of occurrence of these species is higher. This information should be considered as a starting point for further research to fully elucidate the ecology and epidemiology of these species, as well as of the pathogens they transmit.

An investigation of the dielectric dispersion, electrical properties, scaling behavior and optical defects of Ca

We report on an experimental investigation of gamma radiation effects on the electronic and optical properties in carbon delta-doping GaAs/AlGaAs High Electron Mobility Transistors (HEMT) structures. Photoluminescence measurements are used to determine the electron-hole relaxation processes in the GaAs channel. For global information on the carriers dynamics in the structures examined, we studied their interactions with the crystal lattice, thermal activation states defects, the energy level activation. Gamma radiation has changed the electronic and optical properties in GaAs/AlGaAs structures, especially the carriers thermal activation.

In this paper, we develop a three-dimensional configuration of the Tunisian Gamma Irradiation Facility (TGIF) to determine the spatial distribution of gamma absorbed dose rates in the irradiation area at the 60Co source rack. The results are obtained by using the MCNP6 code. Experimental measurements of the gamma absorbed dose rate are performed in order to be compared with the calculated results. Two dosimetry systems are employed to perform measurements: red and amber perpex and cellulose triacetate (CTA). The results of MCNP6 simulations are compared to the absorbed dose measurements for the following experiments: (1) estimation of the 60Co source rack position, (2) isotropy verification of gamma-ray emission, (3) isodose curves of the absorbed dose rate inside the irradiation room, (4) absorbed dose rate distribution in air on four vertical planes, (5) absorbed dose rate distribution in air on four horizontal planes versus increasing distance from the source axis. The root mean square error (RMSE) is employed to check the discrepancy between MCNP6 simulation and dose measurements. The values of RMSE for all experiments vary from 0.5 to 2.6%, showing good agreements between the measured and calculated results. This agreement reveals that the developed model of the TGIF is accurate. It inspires the possibility to use the model on an irradiation processing and a reload of the facility.

This study examines the distributions and behavior of trace elements in five takaout plant samples. Multivariate statistical methods involving principal component analysis and hierarchical cluster analysis are applied. The measurements were performed using 21 elements (Al, B, Ba, Ca, Co, Cr, Cu, Er, Fe, K, La, Mg, Mn, Na, Ni, Sc, Sr, Ti, Y, Yb, Zn) at µg g-1 level determined by ICP-OES. The coefficients calculated for samples indicated a poorly negative correlation between the trace elements and Pr. A strong positive correlations among K, Na, Ca, Mg, Fe, Al, Sr, Ti, Er and Cr show a similarity in their change rules. Also, negative correlations between K and Na with Mn, Zn and Ba were showed, which indicates that these elements haven’t a similarity in their behaviors, the increase of one (K and Na) conducting of decrease of others (Mn, Zn and Ba). The correlation matrix shows that Cr has good consistency with the trace elements in the sample. In particular, the correlation coefficient with Mg followed by Sr, Ca, and Fe correlations. These strong correlations between these variables show the similarity of the phenomena at the origin in takaout plant.

Introduction La tuberculose et le VIH sont des problemes majeurs de sante publique. La co-infection tuberculose VIH est une association grave et mortelle. L’objectif de notre etude est de traiter les aspects epidemiologiques, cliniques, bacteriologiques, radiologiques et evolutifs chez les sujets co-infectes ayant une decouverte recente de leur statut serologie VIH. Methodes C’est une etude retrospective portant sur 28 cas de co-infection VIH et tuberculose colliges entre janvier et juin 2019 au service de phtisiologie de l’hopital Moulay Youssef de Rabat. Resultats Il s’agit de 16 hommes (57 %) et 12 femmes (43 %). L’âge moyen est de 36 ans. 78 % des patients avaient des conduites a risques, l’antecedent de tuberculose etait retrouve dans 7 % des cas et le tabagisme etait present dans 64 % des cas. Les manifestations cliniques etaient dominees par des signes generaux chez tous nos patients, une toux productive retrouvee dans 6 cas, associee a une dyspnee dans 12 cas, hemoptysie retrouvee dans 2 cas et dyspnee dans 6 cas. Sur la radiographie thoracique, les aspects radiologiques retrouves : le syndrome interstitiel dans 64 % des cas, epanchements pleuraux dans 36 % des cas, opacites excavees dans 29 % des cas. La recherche de BAAR etait positive a l’examen direct dans 64 % des cas et dans 36 % des cas, le diagnostic de la tuberculose a ete etabli par la mise en evidence de GeneXpert dans les expectorations bronchiques pour 22 % des cas et dans l’aspiration bronchique pour 14 % des cas. Soixante-dix-neuf pour cent des patients avaient une tuberculose multifocale : miliaire tuberculose retrouvee dans 50 % des cas, tuberculose ganglionnaire dans 50 % des cas, pleurale dans 36 % des cas, osteomedullaire dans 7 %des cas, pericardique dans 7 % des cas et neuro-meninge dans 7 % des cas. Tous les patients etaient mis sous traitement antibacillaire de premiere ligne. Les effets indesirables etaient objectives chez 42 % des patients, qui etaient majeurs dans 22 % des cas, imposant le changement du protocole therapeutique. Le deces est survenu dans 36 % des cas. Conclusion La co-infection tuberculose/VIH est une association grave et dont la tuberculose se declare, dans la majorite des cas, sous ses formes graves. Ceci justifie la mise en œuvre systematique de mesures de prevention chez les patients seropositifs.

This work outlines some interesting results regarding the effects of Pr3+ substitution on the structural and optical properties of (x = 0 and 0.02) samples. Our samples were synthesized using the Pechini sol–gel method. The structural study using Rietveld refinement of XRD patterns showed a hexagonal structure with the P63mc space group for all the samples and also the existence of a secondary phase attributed to the praseodymium oxide (Pr6O11) for 2% wt Pr-doped ZnO. The refinement results revealed that both the lattice parameter and the unit cell volume increase with the increase of Pr content. X-ray peak broadening analysis was used to evaluate the crystallite size and lattice strain by the Williamson–Hall (W–H) method and size–strain plot method (SSPM). The physical parameters such as strain, stress and energy density values were also calculated using the W–H method with different models, namely uniform deformation model (UDM), uniform stress deformation model (USDM) and uniform deformation energy model (UDEDM). The obtained results showed that the mean particle size of the ZnO and Pr0.01Zn0.97O estimated from W–H analysis and the SSPM method are highly intercorrelated. Shifting of the absorption edge to lower wavelength and blue shift of the band gap are observed in the UV-visible spectra of Pr-doped ZnO samples. Particular emphasis was put on the PL measurements of such composites. A noticeable decrease of the maximum intensity of PL response was found after adding Pr3+ to ZnO. This finding is discussed in terms of the photo excited limitation of electron–hole pairs in such nanocomposites.

Muscular involvement with Echinococcusgranulosus is rare, even in endemic countries where the frequency is estimated to be less than 3%, particularly in the countries of the Mediterranean basin, North Africa and Latin America. We report the rare observation of a hydatid cyst of the internal thigh room in a 57-year-old patient of rural origin and who has no notable sickness antecedents and was hospitalized in our department for the exploration of a tumefaction of the internal surface of the left thigh appeared gradually and insidiously for 3 years. Magnetic resonance imaging (MRI) showed an oval mass evoking an intramuscular hydatid cyst and its relationship to neighboring structures. He underwent surgical excision under locoregional anesthesia. Solitary hydatid localization in muscle tissue is exceptional, but it is useful to know that its diagnosis is often delayed, its treatment is surgical, but recurrences are possible.

In this work, we study the inclusion mechanism of Fe3+ ions in a polyvinyl alcohol (PVA) matrix. Pure and Fe3+-doped PVA films, using FeCl3 solution, are prepared by a solution casting method. The effect of Fe3+ doping on the photoluminescence (PL) behavior of PVA is investigated in the temperature range from 10 to 300 K. The PL intensity is found to decrease as the temperature increases for the samples slightly doped. This behavior is attributed to the phonon diffusion by the photo-created electron–hole pairs. However, this behavior is completely inverted when the content of Fe3+ increases. The first author has already published a work discussing the possible explanations of such a behavior where the PL intensity increases with temperature. This paper is devoted to study the thermal activations energy and its variation with doping. Therefore, the PL integrated intensity as a function of 1/T is simulated by the Arrhenius model for the samples whose PL intensity decreases with temperature. However, for the other samples, a model of two activation energies is used. The gap energy values and the PL spectra of all samples at 300 K were used to justify the suggested transitions.

The optical band-gap has been investigated in detail in (InAs)GaAs/AlGaAs HEMTs structures using a photoluminescence spectroscopy. A power dependent PL study allows highlighting the different causes of the shift band-gap. We can explain the shift by more effects: quantum confined Stark effect (QCSE), band-gap renormalisation (BGR) and Burstein–Moss (BM) effects. We are interested in these effects based on the carriers’ behaviour inside GaAs and InAs/GaAs channels. These effects were affected by carrier concentration depending on Si-δ-doping density and AlGaAs spacer layer thickness as well as the strain relaxation effect. The photoluminescence characterisations have been studied in the 1–10 W cm −2 power range.

The glomus tumor or glomangioma are rare benign tumours developed with depends on the glomus neuromyoarteriel. They sit with predilection at the distal extremities of the fingers and especially on the nail bed. Our work is a retrospective study of 12 cases of glomus tumor of the hand, collected in Departement of Orthopaedic and Traumatology Surgery of Avicenne military hospital in Marrakech, Morocco, on a seven years period between January 2010 and December 2016. The goal of our work is to bring up the diagnostic problems of these tumors, to show the contribution of the modern imagery in the diagnosis, to underline the importance of the surgery and finally to evaluate our results and to compare them with the data of the recent literature.

In this work, we investigate two different δ-doping effects (carbon (C) and silicon (Si)) on the electronic and optical properties of n-δ-doping AlGaAs/GaAs HEMTs structures grown by molecular beam epitaxy on (1 0 0) oriented GaAs substrates. Photoluminescence measurements, as function of the silicon and carbon δ-doping, are used to determine the relaxation processes of the electron and the hole in the GaAs channel. Low and room temperatures PL spectra show the optical transitions that occur between the fundamental states of electrons to holes in the GaAs channel. Using C-n-δ-doping improves the two-dimensional electron gas confinement and decrease defects densities in the GaAs channel. For global information on the carriers dynamics in the structures studied, we studied their interactions with the crystal lattice, thermal activation states defects, the doping activation through the analysis of evolution of the PL spectrum depending on the temperature. The bands structures and theoretical activated electron densities have been studied theoretically using the finite differences method to self-consistently and simultaneously solve Schrodinger and Poisson equations written within the Hartree approximation.

The aim of this work is to investigate two different delta-doping (silicon and carbon) after gamma irradiation. Delta-doping GaAs/AlGaAs heterojunctions grown by molecular beam epitaxy on (1 0 0) GaAs substrates have been studied by photoluminescence (PL) spectroscopy. A theoretical study was conducted using the resolution of Schrodinger and Poisson equations written within the Hartree approximation. PL measurements as function of the power excitation at 10 K shows a red-shift due to free carriers effect on properties of GaAs/AlGaAs quantum well (QW). Its dependence on the density of the two-dimensional electron gas (2DEG) at the GaAs/AlGaAs interface has been analyzed on the basis of the quantum confined Stark, the band-gap renormalization and Burstein–Moss (BM) effects. It is noted that the gamma radiation has changed the type of the exciton recombination.

An Irradiated nickel oxide (NiO) thin film was deposited onto glass substrates at 723 K by the spray pyrolysis using nickel chloride as precursors. The obtained films were irradiated by gamma-radiation doses varying from 180 Gy to 10 kGy. The structure and optical properties of the samples were examined by X-ray diffraction, UV–vis spectrometer and photoluminescence measurement. Un-irradiated and irradiated NiO thin films have a cubic structure with the same preferred orientation along the plane (111). XRD investigation shows that, the intensity of preferred orientation and crystallite size depend on gamma-radiation dose. For a study of the dose effect, it is very important to optimize the precursor concentration. With a concentration of 5.10−2M precursor NiCl2 and a dose of 10 kGy, we obtain a thin film of Ni2O3. With a 10 kGy dose we obtain a new dominant phase, Ni2O3, which induced an activation of the visible range under the effect of gamma rays. This improved the photocatalytic performance under gamma rays treatment. Moreover, the PL quenching effect shows an improvement of photocatalytic properties.

Background HIV/AIDS is frequently associated with opportunistic diseases such as leishmaniasis. Hence, the co-infection HIV-Leishmania spp. is the result of the geographical overlap between leishmaniasis and HIV/AIDS cases. To the best of our knowledge, this is the first report describing the spatial distribution of HIV-Leishmaniasis co-infection in Morocco where both infections are endemic. Methods In the current study, we discuss the HIV-Leishmania spp. co-infection vulnerability in Morocco by using the cartography tools. Thus, epidemiological data of both infections (Leishmaniasis and HIV/AIDS) in different administrative regions of Morocco were collected and co-registered for Digital maps making. Results & conclusion The results showed a high risk of HIV-Leishmania infantum co-infection in northern and central regions in Morocco. These results should be taken into account for efficient control strategies and epidemiological surveillance of HIV –Leishmania spp. co-infection in Morocco.

In this paper, pure and Fe 3+ doped polyvinyl alcohol (PVA) films, using FeCl 3 , are prepared by a solution casting method. The effect of Fe 3+ doping on the photoluminescence (PL) behavior of PVA is investigated in the temperature range from 10 to 300 K. At 300 K, the PL spectrum of pure PVA is formed by two bands I 1 and I 2 . These two bands can be connected with trap states inside the band gap. The PL intensities of I 1 and I 2 are found to increase with increasing the doping content. The temperature dependence of the PL intensity for neat PVA shows a decrease in the PL intensity with temperature assigned to the phonon diffusion by the photo-created electron–hole pairs. However, the PL studies of some doped samples containing an important amount of iron reveal an uncommon behavior of their PL intensity which rises with temperature. Two suggestions are given to explain such a behavior. The first is related to the change in the levels nature inside the bandgap and the second is correlated to the (I 1 –I 2 ) energy.

In this work, we investigate the effect of the δ-Si doping on the barrier and the spacer thickness on the electronic properties of AlGaAs/GaAs HEMTs structures grown by molecular beam epitaxy on (1 0 0) oriented GaAs substrates. Photoluminescence measurements as function of the temperature are used to determine the relaxation processes of the electron and the hole in the channel. The photoluminescence characterizations of Si-delta-doped AlGaAs/GaAs HEMTs structures have been studied in the 10–300 K temperature range. Low temperature PL spectra show the optical transition (Ee–h) that occurs between the fundamental states of electrons to holes in the GaAs channel. Increase of the Si-δ-doping density and decrease of the spacer width improve the two-dimensional electron gas confinement and decrease defects densities in the canal. The band structure of Si-delta-doped AlGaAs/GaAs HEMTs structures at T = 10 K has been studied theoretically using the finite differences method to self-consistently and simultaneously solve Schrodinger and Poisson equations written within the Hartree approximation.

Photoreflectance and photoluminescence studies were performed to characterize InAs ultrathin layer embedded in Si-delta-doped GaAs/AlGaAs high electron mobility transistors. These structures were grown by Molecular Beam Epitaxy on (1 0 0) oriented GaAs substrates with different silicon-delta-doped layer densities. Interband energy transitions in the InAs ultrathin layer quantum well were observed below the GaAs band gap in the photoreflectance spectra, and assigned to electron–heavy-hole (Ee–hh) and electron–light-hole (Ee–lh) fundamental transitions. These transitions were shifted to lower energy with increasing silicon-δ-doping density. This effect is in good agreement with our theoretical results based on a self-consistent solution of the coupled Schrodinger and Poisson equations and was explained by increased escape of photogenerated carriers and enhanced Quantum Confined Stark Effect in the Si-delta-doped InAs/GaAs QW. In the photoreflectance spectra, not only the channel well interband energy transitions were observed, but also features associated with the GaAs and AlGaAs bulk layers located at about 1.427 and 1.8 eV, respectively. By analyzing the Franz–Keldysh Oscillations observed in the spectral characteristics of Si-δ-doped samples, we have determined the internal electric field introduced by ionized Si-δ-doped centers. We have observed an increase in the electric field in the InAs ultrathin layer with increasing silicon content. The results are explained in terms of doping dependent ionized impurities densities and surface charges.

Micro-Raman scattering measurements were used to study the silicon delta-doped layer density variation effect on InAs ultrathin layer embedded in silicon-delta-doped GaAs/AlGaAs high electron mobility transistors (HEMTs) structures properties. These structures were grown by molecular beam epitaxy on GaAs substrates with different silicon (Si) delta-doped layer densities. Two coupled plasmon–longitudinal optical (LO) phonon modes (L− and L+) were observed in the micro-Raman spectra of the Si-delta-doped samples, and both their wave numbers and intensities were dependent on the silicon delta-doped layer density. There is evidence to suggest that the increase of the Si doping level results in the increase of exciton–phonon scattering which is mainly due to the incorporation of Si and the increase of the two-dimensional electron gas (2DEG) in the InAs/GaAs interface. From fitting the temperature-dependence of full width at half maximum (FWHM) of quantum well’s photoluminescence peak (P1) by the exciton–photon coupling model, it was found that the interaction between exciton and phonon in Si-delta-doped quantum wells was higher than that in the undoped sample. This result was confirmed as resulting from the increase of plasmon–phonon scattering which is attributed to the increase of free carriers donated from implanted Si dopant. The self-consistent Poisson–Schrodinger model calculation results are in good agreement with the experimental results, where the 2DEG densities increase linearly with increasing the Si-delta-doped layer density.

Photoluminescence (PL) analysis is used to study porous layers elaborated by electrochemical etching of n+ Si-doped GaAs substrate with different etching times. Temperature and power dependence photoluminescence (PL) studies were achieved to characterize the effect of the etching time on the deep levels of the n+ Si-doped GaAs. The energy emission at about 1.46 eV is attributed to the band-to-band (B–B) (e–h) recombination of a hole gas with electrons in the conduction band. The emission band is composed of four deep levels due to the complex of (VAsSiGaVGa), a complex of a (Ga vacancy – donor – As vacancy), a (SiGa–VGa3−) defect or Si clustering, and a (gallium antisite double acceptor-effective mass donor pair complex) and which peaked, respectively, at about (0.94, 1, 1.14, and 1.32 eV). The PL intensity behavior as function of the temperature is investigated, and the experimental results are fitted with a rate equation model with double thermal activation energies.

In this work we study the density and confinement effects of 2DEG InAs ultrathin layer introduced in Si-delta-doped GaAs/AlGaAs heterostructures grown by Molecular Beam Epitaxy (MBE) on (1 0 0) oriented GaAs substrates by photoluminescence (PL) measurements. Low temperature PL spectra show the optical transitions ( E e–hh ) and ( E e–lh ) that occur, respectively, between the fundamental states of electrons to heavy holes, and electrons to light holes, in InAs ultrathin layer. The transition energies have been theoretically calculated by solving simultaneously the Schrodinger and Poisson equations within the Hartree approximation. High 2DEG content reveals high photoluminescence efficiency. In fact, the presence of a high density of defects behaves like traps, which can be saturated by the presence of 2DEG in the InAs channel. Photoluminescence measurements as function of the temperature present an S-shape. The evolution of the temperature-dependent integrated PL intensity of the Si-delta-doped structures is governed by two regimes.

The title compound, 3'-(4-methoxyphenyl)-2-phenyl-4'-(4-ethoxyphenyl)-1,2-dihydro-4H,4'H-spiro[isoquinoline-3,5'-isoxazol]-4-one was synthesized from the reaction of dipolarophile with p-methoxybenzadoxime in the presence of sodium hypochlorite in chloroform solution. The structure of the synthesized compound was determined by IR, H-1 NMR, mass spectroscopic data, C-13 NMR spectroscopy, elemental analysis and X-ray crystallography. The structure was solved in monoclinic, space group C2/c with a = 21.941 (4), b = 17.233 (3), c = 15.404 (3) angstrom, beta = 122.193 (2), V = 4928.9 (16) angstrom(3), Z = 8 and with R-int = 0.154. The geometry of the title compound showed that the piperidine ring adopts a half-chair conformation. In the crystal structure, molecules are linked by C-H center dot center dot center dot O and C-H center dot center dot center dot N contacts. Weak C-H center dot center dot center dot pi p interactions plays an important role in stabilizing the supramolecular structure.

Two novel ligand pyrazole derivatives AH and BH (AH = ((3,5-dimethyl-1H-pyrazole-1- yl)methyl)amino acetic acid, BH = (bis-(3,5-dimethyl-1H-pyrazole-1-yl)methyl)amino acetic acid) formed simultaneously by the condensation of N-hydroxy methyl-3,5-pyrazole (1) with glycine (CH3COOH) and their cobalt(II) or copper(II) mixed ligand complex, with 3,5-dimethyl- 1H-pyrazole (Pz) have been synthesized and characterized by spectroscopic analysis and X-ray diffraction study. Distorted square pyramidal geometry is observed around copper(II) with two nitrogens (N1, N3 of AH) in the first plane and third nitrogen (N4 of one pyrazolic ligand) and two oxygen atoms (O4 and O1) in the second plane. In contrast to Cu(II) cation which coordinates with ligand AH, the Co(II) cation prefers to coordinate with the second ligand BH.

Inhibitory effect of some new synthesized tripyrazole compounds on corrosion of pure iron in 1 M HCl solution has been studied using weight-loss measurements and various electrochemical techniques polarization and impedance spectroscopy methods. The inhibiting action is more pronounced with N,N,N-tris[(3,5-dimethyl-1H-pyrazol-1-yl)methyl] amine (P1), and its inhibition efficiency increases with its concentration and attains the maximum value of 94% at the 2.5 · 10 � 4 M. The effect of temperature on the corrosion behaviour of iron was studied in the range from 298 to 353 K with and without P1 at 2.5 · 10 � 4 M. We note a good agreement between gravimetric and electrochemical methods potentiodynamic polarization and impedance spectroscopy (EIS). Polarization measurements show also that the compound acts mixed inhibitor. The catholic curves indicate that the reduction of proton at the pure iron surface happens within a pure activating mechanism. EIS measurements show the increase of the transfer resistance with the inhibitor concentration. The presence of the N,N,N-tris[(3,5-dimethyl-1H-pyrazol-1-yl)methyl] amine increases the inhibition efficiency and not caused a drastic change in its adsorption mechanism. The adsorption of P1 on the surface of iron in 1 M HCl obeys a Langmuir isotherm adsorption. � 2005 Published by Elsevier Ltd.

Inhibitory effect of some new synthesized bipyrazole compounds, namely, N,N-bis[(3,5-dimethyl-1H-pyrazol-1-yl)methyl]-N-(4-methylphenyl)amine (P1) and methyl-1-[((methylphenyl){[3-(methoxycarbonyl)-5-methyl-1H-pyrazol-1-yl]methyl}amino)methyl]-5-methyl-1H-pyrazole-3-carboxylate (P2) on corrosion of pure iron in 1 M HCl solution has been studied using chemical technique as weight loss and electrochemical techniques as potentiodynamic polarization, linear polarization and impedance. The inhibition efficiencies obtained from gravimetric, cathodic Tafel plots, linear polarization resistance and EIS methods are in good agreement. The results obtained reveal that these compounds are efficient inhibitors. The inhibition efficiency increases with the increase of inhibitor concentration to reach 93% for P1 at 2.5 × 10−4 M. Potentiodynamic polarisation studies clearly reveal that P1 and P2 act as mixed-type inhibitors without change of the mechanism of hydrogen evolution. The temperature effect on the corrosion behaviour of iron in 1 M HCl without and with the inhibitors at 2.5 × 10−4 M has been studied in the temperature range from 298 to 353 K. EIS measurements show that the increase of the transfer resistance with the inhibitor concentration. The inhibitors are adsorbed on the iron surface according to the Langmuir adsorption isotherm model. From the adsorption isotherm some thermodynamic data for the adsorption process (K and Δ G ads ° ) are calculated and discussed.

We present final measurements of the Z boson-lepton coupling asymmetry parameters Ae, Amu, and Atau with the complete sample of polarized Z bosons collected by the SLD detector at the SLAC Linear Collider. From the left-right production and decay polar angle asymmetries in leptonic Z decays we measure Ae = 0.1544 +- 0.0060, Amu = 0.142 +- 0.015, and Atau = 0.136 +- 0.015. Combined with our left-right asymmetry measured from hadronic decays, we find Ae = 0.1516 +- 0.0021. Assuming lepton universality, we obtain a combined effective weak mixing angle of sin**2 theta^{eff}_W = 0.23098 +- 0.00026., 13 pages latex, including 1 figure. Submitted to Phys. Rev. Lett

We have made the first direct symmetry tests in the decays of polarized Z0 bosons into fully identified bbg states, collected in the SLD experiment at SLAC. We searched for evidence of parity violation at the bbg vertex by studying the asymmetries in the b-quark polar- and azimuthal-angle distributions, and for evidence of T-odd, CP-even or CP-odd, final-state interactions by measuring angular correlations between the three-jet plane and the Z0 polarization. We found results consistent with standard model expectations and set 95% C. limits on anomalous contributions.

The authors have made the first direct measurement of the parity-violating coupling of the Z{sup 0} boson to the strange quark, A{sub s}, using {approximately}550,000 e{sup +}e{sup {minus}} --> Z{sup 0} --> hadrons event produced with a polarized electron beam and recorded by the SLD experiment. Z{sup 0} s anti-s events were tagged by the absence of B or D hadrons and the presence in each hemisphere of a high-momentum K{sup {+-}} or K{sub s}{sup 0}. From the polar angle distributions of the strangeness-signed thrust axis, the authors obtained A{sub s} = 0.895{+-}0.066(stat.){+-}0.062(syst.). The analyzing power and u anti-u + d anti-d background were constrained using the data.

The authors have developed a new technique for inclusive reconstruction of the energy of B hadrons. The excellent efficiency and resolution of this technique allow them to make the most precise determination of the b-quark fragmentation function, using e{sup +}e{sup {minus}} {r{underscore}arrow} Z{sup 0} decays recorded in the SLD experiment at SLAC. The authors compared their measurement with the predictions of a number of fragmentation models. The authors excluded several of these models and measured the average scaled energy of weakly-decaying B hadrons to be (x{sub B}) = 0.714{+-}0.005(stat){+-}0.007(syst){+-}0.002 (model-dependence).

The parity violation parameters Ab and Ac of the Zb anti-b and Zc anti-c couplings have been measured directly, using the polar angle dependence of the Z0-pole polarized cross sections. Bottom and charmed hadrons were tagged via semileptonic decays. Both the muon and electron identification algorithms take advantage of new multivariate techniques, incorporating for the first time information from the SLD Cerenkov Ring Imaging Detector. Based on the 1993-95 SLD sample of 150,000 Z0 decays produced with highly polarized electron beams, we measure: Ab = 0.910 ± 0.068(stat) ± 0.037(syst) Ac = 0.642 ± 0.110(stat) ± 0.063(syst).

We present a direct measurement of the parity-violating asymmetry A{sub b} in the Z{sup 0} to b anti-b coupling using a new technique to distinguish the b and anti-b quarks using charged kaons from B decays. The Z{sup 0} bosons are produced in e{sup +}e{sup -} collisions at the SLC with longitudinally polarized electrons. b anti-b events are selected using a secondary vertex mass tag and A{sub b} is determined from the left-right forward-backward asymmetry. From the 1994-1995 data sample, selected from 100,000 hadronic Z{sup 0} decays, we obtain A{sub b} = 0.855 {+-} 0. 088{sub stat} {+-} 0.102{sub sys}.