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Two new mononuclear complexes, [Cu2Cl1.23(NO3)0.77(Ampy)4(H2O)4](NO3)2·4H2O (I) and [CdI2(Ampy)2] (II) (Ampy = 4-amino-6-methoxypyrimidine) have been synthesized and characterized by single crystal X-ray diffraction studies (CCDC nos. 2023331 (I), 2023331 (II)) at 295 K for (I) and 100 K for (II). The structure of the Cu(II) complex shows that the Cu(II) central atom is five-coordinated with a distorted square pyramidal geometry. In compound (II) the Cd(II) cations are tetracoordinated with a distorted tetrahedral fashion. Intermolecular interactions were investigated by Hirshfeld surfaces. Electronic properties such as HOMO and LUMO energies were derived. [ABSTRACT FROM AUTHOR]

The purpose of the present study is to explore the characteristics of the postural control in Kung-Fu trained young boys, in comparison with non-trained age-matched ones. Two groups of 11–13-year old boys (10 practicing Kung-Fu and 10 controls) were asked to maintain upright bipedal and unipedal stances on a force platform with eyes open and closed in a static and two dynamic postures. Postural control was assessed with centre of pressure excursions. Muscle response characteristics were recorded during maintaining a bipedal stance on an unstable platform with eyes open and closed. Kung-Fu practitioners had significantly (P <.05) better balance than controls in dynamic postures. Removal of vision significantly (P <.001) decreased the balance of both groups similarly. In dynamic conditions, controls were affected by removal of vision in both postures, but Kung-Fu practitioners depended on vision in unipedal posture only. Kung-Fu group showed significantly (P <.01) better neuromuscular responses than controls. Removal of vision significantly (P <.05) increased muscle-response amplitude for the two groups. Kung-Fu trained young boys seems to have better postural control in dynamic (unipedal-eyes open and bipedal-eyes closed) postures and better neuromuscular responses compared to non-trained ones. [ABSTRACT FROM AUTHOR]

Abstract: In this study, dielectric and physicochemical properties of thin films prepared in low pressure microwave plasma reactor have been investigated. The films have been deposited from tetramethylsilane or a mixture of tetramethylsilane and oxygen (TMS/O2). The plasma discharge power and the working pressure in the reactor were kept constant and equal to 400 W and 1 mTorr, respectively. The deposition rate and refractive index have been found to decrease with increasing oxygen proportion in the mixture. For films deposited from TMS, the deposition rate and refractive index were about 800 Å/min and 1.55 respectively. Whereas, for films deposited from 90% of O2 and 10% of TMS, their values were in the order of 50 Å/min and 1.47, respectively. When the oxygen rate in the mixture increases, FTIR analysis shows more formation of Si–O–Si groups with a significant decrease of organics groups (such as Si–CH3 and –CH x ). At high oxygen flow rate (90%) in the precursor mixture, the deposited films are SiO x -like structure. The dielectric constant value was close to 3.6 when the films are deposited using low oxygen proportion and close to 4.5 for films deposited with high O2 rate in the precursor. [Copyright &y& Elsevier]

Summary: Objectives: The purpose of the present study is to assess the effect of circus activity training on postural control of 5–6-year old children. Material and methods: Two groups of 5–6-year old children (12 practicing circus activities and 12 controls) voluntarily participated in this study. Children were asked to stand as still as possible on a force platform with eyes open and closed in a static posture and in two dynamic postures (in the sagittal or frontal plane). Postural control was assessed with centre of pressure excursions. Results: The results revealed that Circus group children have significant (P <.05) better postural control than controls. The significant (P <.05) effect of postural task difficulty on postural control was similar for both groups. Removal of vision decreases significantly (P <.05) the postural control of both groups similarly in all postures. This effect increased significantly (P <.05) when the difficulty of the postural task increased. Conclusion: Our results suggest that 2years of experience in circus activity training improves postural control of 5–6-year old children. Nevertheless, this effect could not nullify the common effect of removing vision on postural control of these children. [ABSTRACT FROM AUTHOR]

Abstract: Outcrop data as well as petrographical, tectonic and geochemical data were used to reconstruct the depositional environments of Ypresian–Lower Lutetian-aged carbonate systems bearing Nummulites. They are shelf deposits which pertain to the Metlaoui Group from the northwest and central-east Tunisia, constitute exploration targets for hydrocarbons and form the reservoirs of some important oil-fields at Ashtart and Sidi El Iteyem. Cyclostratigraphy (sedimentary figures, syndepositional faulting, sequence stratigraphy and framework) and laboratory investigations (petrography, geochemical evaluation) were made of these chalky series, to develop a sequence model for the Metlaoui group and clarify the main relationships between global sea-water level changes, lithofacies repartition and source-rock potential. The rock units that include three main third-order sequences, were deposited in a variety of shelf to platform environments with distinct associations of phosphorite/clay/evaporite and carbonate facies. Associated with Nummulitid facies of two main outer shelves, are Globigerinid facies, Discocyclinid subfacies, pack–grainstones enriched in glauconite and phosphate, and Bivalve and Algae-bearing packstones and grainstones. Due to tectonic activity, channels were often cut into the shelf and materials eroded from paleohighs often bypassed the shelf and were deposited in the deep basins. Basin deposits include two main cross-sections: (1) Globigerinid-rich limestones and cherts of the Boudabbous formation and (2) a lateral equivalent with interbedded limestones, clayey limestones, marls and microbreccias which exhibit abundant pyroclastic fragments that testify to an intense Ypresian volcanism. The deposits display substantial heterogeneity resulting from depositional, diagenetic and structural processes. Porosity development in Nummulitid-bearing strata is principally a result (1) of meteoric diagenesis due to uplift and emersion (tests dissolution) and locally dolomitization at the end of short-term cycles (Milankovich cycles) and (2) frequent stylolitization and microfracturation due to late compaction concurrent with transpressional tectonics. Elevated amounts of organic matter were determined in these series, and lithofacies which present high petroleum indices would provide sourcing for seals where the rocks have been deeply buried, notably beneath the Oligocene–Miocene thick series. [Copyright &y& Elsevier]

Abstract: Surface wettability of polypropylene (PP) films has been significantly improved by the deposition of thin SiO x layers, elaborated from a mixture of hexamethyldisiloxane (HMDSO) and oxygen in a microwave DECR (distributed electron cyclotron resonance) plasma reactor (2.45 GHz, 400 W). Contact angle measurements, Atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) were used to study, respectively, the change in surface free energy, surface topography and chemical composition due to the deposition of thin SiO x layers. Contact angle measurements revealed that the water contact angle value is reduced from about 99° for untreated PP surface to nearly 30° for coated PP film. The polar component of the surface energy is considerably increased from 0.5 to 35 mJ/m2. For films deposited in the presence of VUV photons, AFM images showed the growth of irregular structure due to substrate etching effect and the deconvolution results of the Si 2p XPS peaks indicated that the proportion of the partly oxidized silicon environment was the major component. However, for films deposited without the presence of VUV radiation, typical SiO2 agglomerates can clearly be seen on PP surface at a thickness of about 29 nm and the proportion of the silicon dioxide was the major component. [Copyright &y& Elsevier]

Surface potential decay after negative corona charge deposition has been studied for polypropylene films 50 μm thick, over a wide range of decay times and charging voltage (500–2800 V). At low initial potential (500–800 V), the surface potentials were stable and did not decay. At high initial potential (1200–2800 V), the surface potential decay has been clearly observed with differences in the decay rate. The observed decay behavior has been computer simulated to elucidate the transport mechanism in polypropylene films. A good agreement between measured and calculated decay curves was obtained with a model in which charges are transported by hopping of injected carriers between localized trapping centers. The model is characterized by parameters such as the free carrier mobility, the mean free time of carrier between traps and the mean capture time in trap. The transport parameters have been determined by a fitting procedure. [Copyright &y& Elsevier]

Measures B-doped crystalline diamond film chemically vapor deposited on undoped and polished polycrystalline diamond using current voltage measurements. Role of grains and grain boundaries (GB) in electronic and mechanical properties; Effects of GB on the electrical properties of polycrystalline; Comparison of the properties of single crystal and polycrystalline diamond.

Background: This study aimed to compare the effects of a designed program based on games situations with those of a conventional one, the Adapted Physical Education (APE) program, on the fundamental movement skills (FMS) in children with Down Syndrome (DS), aged 6 to 10. Methods: Twenty‐eight children (13 girls and 15 boys; age 8.84 ± 1.06) with DS participated in this study. The participants were divided into two groups as the experimental group (EG) with 13 children (3 girls and 10 boys) and the control group (CG) composed with 15 children (10 girls and 5 boys). The EG participated in a conceived training program based on games situations along 10 weeks, while the CG took part in an APE conventional program based on football, long Jump and sprint adapted exercises. The FMS (locomotor and object control skills) were evaluated using the Gross Motor Development‐2 Test at pretraining and posttraining for both groups. Results: The results revealed that both programs improve significantly locomotor skills with significantly better improvement in the EG. However, a significant object control skills improvement was observed only among the EG. Conclusions: In light of our findings, a training program based on adapted games situations during 10 weeks may be recommended for FMS improvement, specifically object control skills. [ABSTRACT FROM AUTHOR]

In previous work, nanopowders have been obtained during the deposition of thin layers from Hexamethyldisiloxane (HMDSO) using low frequency plasma. The aim of this work is the study of the growth process of these nanopowders in plasma discharge and in deposited films. The plasma discharge was generated from HMDSO precursor in low frequency reactor; optical emission spectroscopy (OES) and scanning electron microscopy (SEM) have been used to investigate the effect of the deposition parameters on the nanopowders growth in the plasma discharge and in the deposited thin layers respectively. For high deposition pressure, OES reveals the presence of SiH (situated at 414 nm), OH (situated at 309 nm), CHO (situated at: 324.3, 351.5 nm) species and some additional emission peaks of CO (situated at: 540.9, 566.6, 578, 646,6 nm). The intensities evolution of these species have been investigated during the discharge plasma and the presence of some of them may be the result from the reaction of the nanoparticles of the deposited powders with the plasma species. Nanoparticles agglomerations have been revealed by SEM observations and their aspect correlated with optical emission spectroscopy measurements. [ABSTRACT FROM AUTHOR]

A four-point probe method is used to study the effect of a 10 min anneal in N2 at 600 °C on the resistivity of B-doped chemical vapor deposited diamond samples as a function of doping and film quality, as determined by Raman spectroscopy. Measurements on diamond films deposited on oxidized Si having resistivities in the ranges of 0.27–535 Ω cm, show that the increase of resistivity after the anneal is more prominent for films with low doping and high quality. There seems to be a doping level above which the effect of anneal is not observable. the dependence of the effect of anneal on the doping level and diamond quality is reported. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Introduction: La cholécystectomie sous séreuse par voie laparoscopique est validée et ses avantages ne sont plus à démontrer. Le but de ce travail est de rapporter la faisabilité de cette technique et ses particularités. Matériel et Méthodes: Notre travail s’est basé sur une étude rétrospective sur 40 enfants hospitalisés entre janvier 1997 et janvier 2010 pour cholécystectomie. L’âge variait entre 2 et 20 ans. La symptomatologie clinique était dominée par les douleurs abdominales (24), une cholécystite aigüe (4) et une découverte fortuite (4). Le diagnostic était posé à l’échographie. L’abord coelioscopique était réalisé selon la « french position » avec mise en place de 4 trocarts. Le canal cystique était sectionné après « clipage », alors que l’artère cystique était coagulée. Aucun malade n’a été drainé. La perforation de la vésicule biliaire n’a pas nécessité de conversion. La durée de l’intervention était en moyenne de 45 mn. La durée moyenne du séjour était de 2j. Les suites opératoires étaient simples dans tous les cas avec une morbidité et une mortalité nulle. Conclusion: La cholécystectomie sous séreuse se distingue par le risque moindre de perforation et de saignement du lit hépatique.Sa réalisation sous coelioscopie offre des suites simples, peu douloureuse set sans cicatrice résiduelle. [ABSTRACT FROM AUTHOR]

Introduction: Les malformations adénomatoides kystiques pulmonaires (MAKP) sont des lésions kystiques rares du poumon. Elles correspondent à un défaut de développement des alvéoles associé à une prolifération anormale des bronchioles terminales, donnant ainsi naissance à des kystes de taille variable. But: Il s’agit d’une étude rétrospective ayant intéressé 3 enfants présentant une MAKP. Nous avons analysé les manifestations cliniques, radiologiques ainsi que les résultats histologiques afin d’apprécier l’évolution après le traitement chirurgical. Patients et Méthodes: Nous rapportons 3 observations de MAKP : 2 filles et un garçon. La moyenne d’âge de nos patients était de 56 mois. Dans aucun cas un diagnostic anténatal n’a été établi. Tous nos patients avaient un score d’Apgar normal à la naissance. L’un de nos patients était symptomatique avant l’âge de deux ans. La symptomatologie d’appel était sous forme d’infections broncho-pulmonaires traînantes et récidivantes chez deux enfants. Dans le 3ème cas il a été suspecté un abcès du poumon devant la fièvre, l’asthénie et les secrétions purulentes. Dans un cas il existait une dextrocardie avec hypoplasie pulmonaire. La radiographie du thorax ainsi que la tomodensitométrie ont montré de multiples formations kystiques du lobe supérieur gauche dans deux cas et du lobe inférieur droit dans un cas, confirmant ainsi le diagnostic de MAKP. Dans un cas, la radiographie pulmonaire a montré de multiples niveaux hydro aériques. Tous nos patients ont été opérés, une thoracotomie a été réalisée avec une lobectomie dans deux cas et une pneumonectomie dans un cas. L’examen anatomopathologique a permis de confirmer le diagnostic : dans un cas il s’agissait d’un Stocker I, d’un stocker 2 dans un cas et d’une forme hybride dans le 3ème cas associant un hamartome avec des lésions de MAKP type 2 de Stocker. Un recul de 5 mois montre une convalescence normale. Conclusion: Le diagnostic prénatal des MAKP est base sur l’imagerie par résonance magnétique et nucléaire entre la 20ème et la 28e semaine d’aménorrhée. Les infections broncho-pulmonaires traînantes et récidivantes représentent la symptomatologie d’appel la plus fréquente. La thoracoscopie offre une possibilité d’exérèse des lésions kystiques. La surveillance post opératoire doit être prolongée. [Copyright &y& Elsevier]

Abstract: Hexamethyldisiloxane (HMDSO) thin films coated quartz crystal microbalance (QCM) electrodes have been characterized for the detection of volatile organic compounds (VOCs). The sensitive coatings were plasma polymerized in pure vapor of HMDSO and HMDSO/O2 mixture. The sensor sensitivity was evaluated by monitoring the frequency shift (∆f) of the coated QCM electrode exposed to different concentrations of VOC vapors, such as ethanol, methanol, benzene and chloroform. The isotherm response characteristics showed good reproducibility and reversibility. For all types of analyte, ∆f were found to be linearly correlated with the concentration of VOC vapor. It was shown that it is possible to tune the chemical affinity of the sensor by changing the oxygen ratio in the deposition gas mixture. Contact angle measurements (CA), attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used to study surface wettability, chemical composition and surface morphology of the coated QCM electrodes. ATR-FTIR analysis showed the presence of methyl groups around 840cm−1 due to Si (CH3)3 rocking vibration making the elaborated sensor surface hydrophobic. When the coating is performed in HMDSO/O2 mixture, AFM and SEM images showed an increase in the effective specific surface area of the sensor due to the increase in surface roughness. Surface morphology combined with chemical composition significantly affects the sensitivity of the QCM-based sensor. [Copyright &y& Elsevier]

A two-dimensional (2D) self-consistent fluid simulation of dual frequency capacitively coupled radio discharges of helium plasma is presented. The model solves the continuity equations for charged species and the electron energy balance equation, coupled with Poisson's equation by finite element method, using COMSOL Multiphysics software. In this study, the low frequency (LF) is set to 13.56 MHz with low frequency voltage of 250 V and the high frequency (HF) is set to 54.24 MHz with high frequency voltage of 100 V. The simulations yield the two-dimensional profiles of plasma components as well as the charge densities, electric field, electron temperature and ionization rate between symmetric parallel plate electrodes. The effects of low and high frequency sources parameters such as frequency values and applied voltage amplitude on the discharge characteristics are investigated. It is shown that the increase of the HF frequency causes a moderate increase of electron temperature and plasma density, whereas, the increase of the LF potential produced an increase in the plasma potential, the voltage of the sheath and the ion energy. [ABSTRACT FROM AUTHOR]

Abstract: In this work, surface properties of polyimide (PI) films coated by thin layers deposited from pure hexamethyldisiloxane (HMDSO) vapours in low frequency powered plasma reactor have been investigated. The polymer thin layers were elaborated at different plasma treatment times. The surface characterization of the coated PI film is performed using attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), refractive index, scanning electron microscopy (SEM), water droplet contact angle measurements and surface potential decay. The high carbon content revealed by ATR-FTIR analysis makes the coated surface PI films more hydrophobic. The water contact angle increased from 63° for untreated film to 115° after 10 min of HMDSO plasma coating. The coated PI surfaces were found to stay practically unchanged following storage of the samples in ambient conditions, indicating stable hydrophobic surface treatments. The increase of the refractive index indicates less porous structure. Scanning electron microscopy images showed a homogenous coating without crack. Surface potential evolution after corona charge deposition showed the retention of deposited charges at the surface of coated PI film. Correlation between these different analysis techniques results has been discussed. [Copyright &y& Elsevier]

Abstract: The response of resistive-type sensors based on thin hexamethyldisiloxane layers to relative humidity (RH) was evaluated. Humidity sensitive layers were plasma polymerized at low frequency glow discharge using a capacitively coupled parallel plate reactor. The sensor design comprises the absorbing layer deposited on clean glass substrate with comb-shape aluminum electrodes (interdigitated structure). The change in electrical impedance of the sensing film was monitored as the device was exposed to humidity. The variation of the plasma-polymerization parameters resulted in different humidity sensing properties which could be correlated to the results of Fourier transform infrared spectroscopy (FTIR). The deposited films exhibited a detectable response to RH ranging from 30 to 95% with low hysteresis, good reproducibility and stability in long-term use. Films with a greater thickness showed a significant decrease in the humidity sensing capability. FTIR analysis revealed the presence of SiH bonding groups, which are frequently linked to the film density. The increase in the plasma discharge power induced also a significant decrease in the diffusion process of water vapor inside the sensitive layer bulk. [Copyright &y& Elsevier]

Abstract: Wettability of polyimide (PI) and polypropylene (PP) films have been improved using SiO x -like thin layers deposited from a mixture of hexamethyldisiloxane (HMDSO) and oxygen in a microwave distributed electron cyclotron resonance plasma reactor. The films wettability evolution behaviors were evaluated through the results of contact angle measurements, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The plasma depositions of SiO x thin layers in presence of VUV radiation induce a contact angle decrease to about 7° and 35° for PI and PP films, respectively. XPS data showed that such difference in wettability is attributed to the increase of hydrophilic group''s proportion at the surface of coated PI films due to VUV irradiation. AFM images showed that the PI surface topography remains relatively smooth when coated in presence of VUV radiation. However, in the case of PP films, AFM images revealed the growth of irregular structure due to a substrate etching effect supported by VUV radiation. For polymers coated without VUV irradiation, the deconvolution of the C1s peaks showed a significant decrease of Cor both PI and PP substrates. [Copyright &y& Elsevier]

The nasal angiocentric T-cell-natural killer cell lymphoma is an aggressive tumor, exceptional in Tunisia, which is observed especially in Asia, Mexico and South America. We report the case of an 11-year-old boy, presenting with an exuberant and ulcerative tumor of the right nasal pit. Radiological investigation evidenced a right ethmoi¨do-frontal tumor. Evolution was characterized by the installation of abdominal pain and fever, the evidenciation of a mass within the head of the pancreas that compressed the extra hepatic biliary duct and Wirsung’s canal and was associated to hyperamylasemia. Biopsy under ultrasound revealed a histiocytic nature. Nasal biopsy found histiocytic and lymphocytic cells and led to a diagnosis of rhinoscleroma. The absence of improvement under antibiotic treatment and the development of fever with leuconeutropenia oriented towards the diagnosis of a non-Hodgkinian malignant lymphoma. Medullary biopsy and immunohistochimic study confirmed a T/NK cells lymphoma, with medullary invasion. The child died from acute respiratory distress syndrome. The authors insist on the rarity of this bipolar location, in particular in children, emphasize the difficulty of the diagnosis and review the literature. [Copyright &y& Elsevier]

Low k dielectric thin films were elaborated in microwave distributed electron cyclotron resonance reactor by using organosilicon vapor and oxygen mixture as precursors. The dielectric constant evolution was studied as a function of the oxygen addition. Contribution of each permittivity component to the variation of the measured dielectric constant was carried out. Although the electronic and ionic polarizations have their influences on the value of the measured permittivity, they have not shown any effect on its evolution. A method to follow the dipolar polarization contribution to the dielectric constant is described. It suggests that both Si–O and Si–C polar groups present in the deposited films may have the predominant effect on the behavior of the dielectric constant. [Copyright &y& Elsevier]

Background: This study explored the effect of running exercises at low [30% heart rate reserve (HRR)] and moderate (60%HRR) intensities on cognitive performances in individuals with intellectual disability (ID). Methods: Participants performed randomly reaction time (RT) tests: visual RT [simple RT (SRT) and choice RT (CRT)], auditory SRT (ASRT) and working memory (WM) (Corsi test) before and after the exercises. Results: The results showed that after both exercises, SRT decreased significantly (P < 0.001) in both groups with higher extent (P < 0.05) at 60%HRR compared with 30%HRR. CRT decreased (P < 0.01), similarly, after the both exercises in both groups with higher (P < 0.001) extent in the intellectual disability group (IDG). ASRT decreased significantly, at 30%HRR, in IDG (P < 0.001) and in control group (CG) (P < 0.01) with greater extent in IDG (P < 0.001). At 60%HRR, ASRT decreased significantly in both groups (P < 0.001) with greater extent in IDG (P < 0.001). The ΔASRT% was significantly (P < 0.05) higher at 30%HRR compared with 60%HRR in IDG. In CG, no significant (P = 0.21) difference was reported between intensities. The Corsi forward and the Corsi backward scores increased significantly (P < 0.01) in both groups after both intensities with higher extent in IDG (P < 0.01). Conclusions: Our results suggest that low and moderate running exercises improve similarly simple and choice visual RT as well as WM in individuals with ID. Furthermore, low‐intensity exercise could be more appropriate to enhance ASRT compared the moderate one in these individuals. Therefore, low‐intensity exercise seems to be an efficient strategy to improve cognitive performances in individuals with ID. [ABSTRACT FROM AUTHOR]

Background: This study aimed to explore muscle strength production and its underlying neuromuscular characteristics in sedentary and trained individuals with intellectual disability (ID) compared with healthy sedentary individuals. Methods: Three adult groups (age: 25.07 ± 0.70) consisting of sedentary individuals with ID (IDSG), trained individuals with ID (IDTG) and a control group (CONT) participated in the present study. Peak torque (PT) during maximal voluntary isometric contraction, voluntary activation level (VAL), surface electromyography (sEMG) recordings, electrophysiological (Mmax) and potentiated twitch torque (PTT responses) of the knee extensor muscles and thigh muscle volume were assessed. Results: Compared with CONT and IDTG, respectively, IDSG presented significantly lower PT (−48% and −42%), VAL (−24% and −9%), sEMG (−49% and −29%), Mmax (−41% and −39%) and PTT (−32% and −28%) values. These deficits were reduced between IDTG compared with CONT (i.e. PT: −10%; VAL: −16%; and sEMG: −28%) or did not differ anymore (PTT and Mmax). Normalising PT to thigh muscle volume and/or computing theoretical PT value overwhelm strength production differences between IDTG and CONT. Training background influences the outcomes with IDTG exhibiting greater PT, VAL, sEMG, Mmax and PTT than IDSG. Conclusions: Strength production deficit in IDSG was related to both muscular and neural characteristics compared with healthy controls whereas this deficit mainly arises from neural characteristics for IDTG. [ABSTRACT FROM AUTHOR]

Ovarian masses requiring surgical intervention are uncommon in the pediatric population. Our aim is to report results of a multicentric Tunisian study concerning the clinical practice and the management of pediatric ovarian masses and to identify the factors that are associated with ovarian preservation. Between January 2000 and December 2015, 98 pediatric patients (<14 years) were surgically treated for ovarian masses at the five pediatric surgery departments in Tunisia. Ninety-eight patients were included in this study. The mean age of the patients at time of surgery was 8.46 ± 4.87 years. Sixty-three ovarian masses (64.3%) were non-neoplastic lesions, 24 (24.5%) were benign tumors, and 11 (11.2%) were malignant neoplasms. Conservative surgery (ovarian-preserving surgery) was successfully performed in 72.4% of the benign lesions, whereas only three patients (27.3%) with malignant tumors underwent ovary-sparing tumor resection (p < .001). The mean diameter of the tumors in the patients who underwent oophorectomy was significantly larger than that in the patients who underwent conservative surgery (7.8 ± 3.9 cm vs. 5.7 ± 2.9 cm, respectively,p = .001). In our study, the risk factors for oophorectomy were a malignant pathology and large tumor size. In accordance with the Gynecologic Cancer Intergroup consensus, we recommend that surgical management of ovarian masses in children should be based on ovarian-preserving surgery. [ABSTRACT FROM AUTHOR]

Chemical sensors generally suffer from the cross-sensitivity problem. For this purpose, the identification of volatile organic compounds (VOCs) using unselective sensor requires a combination of sensors followed by pattern recognition methods. In the current study, four quartz crystal microbalances (QCMs) were coated by plasma-enhanced chemical vapor deposition (PECVD) with the pure vapor of hexamethyldisiloxane (HMDSO) at monomer pressures ranging from 5 to 40 Pa. The coated QCM-based sensors were used for the detection of volatile organic molecules. The sensor responses toward different VOCs showed the possibility to tune the chemical affinity of the sensors by changing only the monomer pressure during the sensitive layer deposition process. Fourier transform infrared (FTIR) spectroscopy and atomic force microscopy (AFM) were used to investigate chemical composition and surface morphology of the coated QCM sensors, respectively. The sensor responses have been used as a database for the identification of VOCs using pattern recognition methods such as principal component analysis (PCA) and artificial neural networks (ANNs). PCA is a linear method that allowed the identification of ethanol only among two other VOCs. Complete identification and accurate quantification of the studied VOCs have been achieved by the combination of PCA for data preprocessing and ANN for pattern recognition. [ABSTRACT FROM PUBLISHER]

Abstract: Amorphous hydrogenated carbon (a-C:H) thin films have been deposited from pure methane discharges in Microwave Multipolar Plasma excited at Distributed Electron Cyclotron Resonance (MMP-DECR). Investigations on the effect of process parameters on the film physico-chemical and electrical properties have been carried out. The plasma discharge power has a significant effect on the film density and on the concentrations of sp3- and sp2-hybridized carbon atoms. These latter (sp3 and sp2 fractions) are also dependant on the deposition time. A low sp2 fraction was obtained in films deposited at high plasma discharge power and/or long deposition time. Moreover, increasing the plasma discharge power leads to less dense films. The film permittivity at 1 kHz is ranging from 3.8 to 2.3 depending on the two process parameters. This evolution of the dielectric constant is correlated to the film density and structure. The current voltage characteristics I (V) of Metal-Insulating-Metal structures using the different films suggest that the carrier transport in a-C:H thin films deposited by MMP-DECR is limited by a space charge conduction mechanism. [Copyright &y& Elsevier]

Presents an optimized experimental method for measuring thermal conductivity of thin, boron-doped diamond films. Creation of thermal fields by Joule heating; Application of parameter estimation to determine the thermal conductivity of the film; Selection of the experimental design.

In this work, we report the implementation of the ultra-fast transient hot strip (THS) technique for measuring the anisotropic thermal conductivity of aluminum nitride (AlN) thin-films. AlN films were produced by reactive DC magnetron sputtering grown at low temperature (>250 °C) on silicon oxide (SiO 2) thin-film produced on a silicon substrate. Precise measurement of thermal conductivity was performed with an experimental device generating ultra-short electrical pulses, and subsequent temperature increases were electrically measured on nanosecond and microsecond time scales. The electrical pulses were applied within metalized strips patterned on SiO 2 before AlN elaboration and the temperature increases were analyzed within time periods selected in the range [0.1–10 μs]. AlN thermal conductivity of cross-plane (in-plane) increased from 60 to 90 W m−1K−1 (33–44 W m−1K−1) when thickness was raised from 1 to 2 μm, respectively. This shows clearly the anisotropy in thermal conductivity of AlN films. In addition, the volumetric heat capacity of AlN was estimated to be ~2.5 × 106 J K−1 m−3. [ABSTRACT FROM AUTHOR]

Objectifs: Le diverticule de Meckel est un reliquat embryonnaire résultant de l’involution incomplète du canal omphalo-mésentérique. Son incidence dans la population générale est de 2 % et est habituellement asymptomatique. Le risque de survenue d’un accident sur le diverticule est de 25 à 30 %. Ce risque est plus élevé chez l’enfant (70 %). Patients et Méthodes: Les auteurs rapportent leur expérience dans la prise en charge des complications du diverticule qui représentent 69 % sur un total de 83 observations colligées entre 1967 et 2007. L’age moyen était de 4 ans avec des extrêmes de 8mois et de 12ans. Le sexe ratio était de 6. Résultats: Les accidents mécaniques étaient les plus fréquents (55,17 %), représentés par une occlusion sur volvulus ou sur bride congénitale (31 %), une invagination intestinale aigue (20,69 %) et la torsion isolée du diverticule (3,45 %). Les complications infectieuses étaient observées dans 31,03 % des cas. Il s’agissait d’une péritonite par perforation (15,52 %) ou d’une diverticulite (15,52 %). Enfin une rectorragie abondante avec déglobulisation était présente dans 15,52 % des cas. Tous les malades étaient opérés. Nous avons réalisé une résection intestinale emportant le diverticule dans tous les cas, suivie d’un rétablissement immédiat de la continuité (93,1 %) ou secondaire après iléostomie temporaire (6,9 %). L’étude histo-pathologique a révélé une hétérotopie gastrique dans 7 cas (12,07 %) et un pancréas aberrant dans 2 cas (3,45 %). Les suites opératoires étaient simples dans la majorité des cas (57cas). Nous déplorons un décès chez un enfant de 4 ans opéré pour un volvulus du grêle sur bride congénitale avec nécrose intestinale étendue compliquée d’un état de choc septique fatal au troisième jour post-opératoire. Conclusion: L’indication chirurgicale ne se discute guère en cas de complications du diverticule de Meckel dont le traitement peut se justifier par un abord coelioscopique. La précocité du diagnostic permet d’améliorer le pronostic et d’éviter le recours à des interventions mutilantes exposant à un grêle court postopératoire ou un sacrifice de la valvule iléo-cæcale. [Copyright &y& Elsevier]