Optical Properties of Wide Band Gap Indium Sulphide Thin Films Obtained by Physical Vapor Deposition

Thin films of indium sulphide containing oxygen have been synthesized following a dry physical process. The constituents are deposited by thermal evaporation on glass substrates and then annealed under argon flow. Polycrystalline β-In2S3 containing oxygen thin films are obtained as soon as the temperature of annealing is between 623 and 723 K. In this paper, these β-In2S3 thin films have optically been studied. The optical band gap is direct. Its value is not dependent on the temperature of annealing. It is about 2.8 eV, which is higher than that of β-In2S3 single crystal. This high value is related to the presence of oxygen in the films. The extinction coefficient k and the refractive index n of the films have also been found independent of the annealing temperature. These optical properties make the films studied good candidates to be substituted to CdS in Cu(In,Ga)Se2 based solar cells

Experimental study of solar energy potential in the gulf of Tunis, Tunisia

Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.This work carries out the availability of the global solar radiation over the site of Borj-Cedria in the gulf of Tunis (36°43’04” N latitude and 10°25’41” E longitude), Tunisia. Global solar radiation variability was assessed on hourly, daily, monthly and seasonal scales. Solar potential in the gulf of Tunis was evaluated using the solar radiation data collected by the meteorological NRG weather station installed in the Centre of Research and Technologies of Energy (CRTEn) in the Borj- Cedria area. The collected measurements during the last three years (2008, 2009 and 2010) were based on 10 minute time step. These data have allowed us to evaluate the global solar flux, the sun duration, the yearly and the seasonal frequency distribution of the global solar radiation. Moreover, a conventional model has been used to estimate the hourly solar radiation on a horizontal plane and it has been validated by experimental measurements in specific days. The results show that the global solar radiation predicted by the conventional model has a good agreement with the experimental data during the clear sky conditions with a relative error percentage of 4.1%. However, the limitation of the conventional model appears under the cloudy sky weather which is proved by the highest value of relative error percentage reaching 14.26% occurred during the autumnal equinox day.dc201

Modeling and investigation of the wind resource in the gulf of Tunis, Tunisia

Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.The development of wind energy conversion systems becomes one of the most important aims of any developing countries such as Tunisia. This is due to the reduction in wind turbine costs, and in fossil fuel atmospheric pollution. The evaluation of wind power potential is very necessary to estimate wind resource and therefore conduct the suitable decisions for the wind power generation projects, technical and economical feasibility researches. The presented work in this paper was to investigate the potential of wind resource in the Gulf of Tunis in Tunisia. The hourly mean wind speed and wind direction with a 10-min time step provided by the NRG weather station were used to analyze the wind speed characteristics and the wind power potential. Weibull parameters are estimated based on the most frequently used methods which their accuracy was compared on different goodness of fit tests. Those wind characteristics are required to give wind project users the picture of wind potential in the Gulf of Tunis.dc201

Association of the Type 2 Diabetes Mellitus Susceptibility Gene, TCF7L2, with Schizophrenia in an Arab-Israeli Family Sample

Many reports in different populations have demonstrated linkage of the 10q24–q26 region to schizophrenia, thus encouraging further analysis of this locus for detection of specific schizophrenia genes. Our group previously reported linkage of the 10q24–q26 region to schizophrenia in a unique, homogeneous sample of Arab-Israeli families with multiple schizophrenia-affected individuals, under a dominant model of inheritance. To further explore this candidate region and identify specific susceptibility variants within it, we performed re-analysis of the 10q24-26 genotype data, taken from our previous genome-wide association study (GWAS) (Alkelai et al, 2011). We analyzed 2089 SNPs in an extended sample of 57 Arab Israeli families (189 genotyped individuals), under the dominant model of inheritance, which best fits this locus according to previously performed MOD score analysis. We found significant association with schizophrenia of the TCF7L2 gene intronic SNP, rs12573128, (p = 7.01×10−6) and of the nearby intergenic SNP, rs1033772, (p = 6.59×10−6) which is positioned between TCF7L2 and HABP2. TCF7L2 is one of the best confirmed susceptibility genes for type 2 diabetes (T2D) among different ethnic groups, has a role in pancreatic beta cell function and may contribute to the comorbidity of schizophrenia and T2D. These preliminary results independently support previous findings regarding a possible role of TCF7L2 in susceptibility to schizophrenia, and strengthen the importance of integrating linkage analysis models of inheritance while performing association analyses in regions of interest. Further validation studies in additional populations are required

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Élaboration à basse température de couches minces D'ln

Des couches minces d'oxyde d'indium ont été obtenues par évaporation thermique réactive et par évaporation réactive assistée par plasma. La source d'évaporation est de l'indium métallique.L'atmosphère pendant le dépôt est composée d'un mélange oxygène-argon ou d'oxygène pur suivant qu’il s'agit de l'évaporation réactive assistée par plasma ou de l'évaporation réactive. Les paramètres variables, outre la technique de dépôt, sont la température du substrat et la pression d'oxygène. Les couches ont été caractérisées par diffraction de rayons X, microscopie électronique à balayage, spectroscopie de photoélectrons, absorption optique, et mesure de conductivité. La comparaison des résultats obtenus montre que les couches évaporées sur des substrats chauffés à 423 K sont polycristallins et se situent dans la fourchette habituelle des résultats de transmission optique et de conductivité des couches minces de In2O3, les meilleurs résultats étant obtenus pour une pression d'oxygène de 6,65 10-2 Pa.Dans le cas des couches déposées à 348 K les dépôts obtenus par évaporation réactive assistée par plasma donnent des résultats supérieurs à ceux obtenus par évaporation réactive simple, cependant les couches sont amorphes d'où des performances moindres en matières de conductivité électrique : alors que leurs performances optiques sont satisfaisantes, leurs propriétés électriques sont à améliorer

Grain boundary conductivity in different polycrystalline MoSe2_2 thin films

It has been shown early that curved plots for the conductivity of polycrystalline diselenide molybdenum were systematically obtained whatever the technique used for the obtention of the layers. In the general case of polycrystalline semiconductors these deviations from the simple thermoionic emission across the grain boundaries have been recently attributed to potential fluctuations at the grain boundaries. Here a good agreement between the experimental results and this new theory is obtained. The result deduced from theoretical propositions is conforted by the scanning electron micrographs of the layers and other preceeding experimental studies. In the light of the discussion of the MoSe$_2$ layers, a quality factor $Q$ is proposed for photovoltaic thin films. This estimation shows that the films obtained by solid state reaction and substitution are the best. Mo and Te thin films are sequentially deposited. Then an annealing under Se and Te pressure at 770 K for 24 h gives crystallized and stoichiometric MoSe$_2$ thin films. These films have the higher quality factor among the films studied here $(Q = 0.75)$. This is in close agreement with the good electrical and optical properties of these layers