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Using the first principal study, we present and discuss the structural, electronic, and magnetic properties of an ordered double perovskite Ba2FeMoO6 in the cubic (Fm-3 m) and tetragonal (I4/mmm) symmetries. The phase stability for ferromagnetic and paramagnetic states has been treated by applying the generalized gradient approximation (GGA-08). Moreover, the calculated lattice parameters are found to be in good agreement with experimental data. For understanding the electronic properties in the studies Ba2FeMoO6, band structure, and total and partial density of states have also been performed and discussed thoroughly. On the other hand, the Monte Carlo simulations were used to study the magnetic properties of Ba2FeMoO6. The Curie temperature was established. The magnetic entropy changes and relative cooling power were deduced. Finally, the magnetic hysteresis cycle was given. The tunability of TC and magnetocaloric properties, the reversible magnetocaloric effect, and the simple fabrication of the samples investigated here suggest a new research area for the development more promising magnetic coolers. [ABSTRACT FROM AUTHOR]

Because of their technological interest in electronics, optoelectronics, sensor technology, and spectroscopic photon counting X-ray photodiode, the AlxIn1-xP alloys have been studied extensively. The ground state structure, mechanical, electronic, optical, and thermodynamic properties for the ternary alloys AlxIn1-xP in the cubic structure are presented. The theoretical calculations are performed using the generalized gradient approximation (GGA) and the semilocal modified Becke–Johnson (mBJ). Although the mBJ (GGA) energy band gap varies nonlinearly with Al concentration, the obtained values agree well with the available experimental data. Interestingly, it is found that at 83% Al, a transition from direct to indirect gap occurs because the binary compounds InP and AlP compounds have a direct band gap ( Γ → Γ ) and an indirect band gap ( Γ → X ), respectively. The thermodynamic study reveals that AlxIn1-xP alloys are stable at high temperature, with the existence of a solid solution for all compositions. Furthermore, at the critical composition xc = 0.55, the value of the direct band gap varies in the narrow range 2.429–2.413 eV, corresponding to the wavelengths 514–513 nm. Consequently, this range of energy band gap recommends the ternary AlxIn1-xP alloys for optoelectronic device applications, such as solar cells or photovoltaic. [ABSTRACT FROM AUTHOR]

The structural stability as well as the mechanical, magnetoelectronic and thermal properties of the quaternary Heusler KMgNZ (Z = O or S) were studied using first principles approach based on the DFT implemented in Wien2k code. The exchange-correlation potential is treated by PBE-GGA. The calculated negative formation energies for both materials corroborate their thermodynamic stability. Moreover, the derived elastic constants support the mechanical stabilities of the latter compounds. On the other hand, the density of states of the studied materials shows that both compounds are half-metallic ferromagnets. The total magnetic moments for both compounds are mainly originated from N atom, and its integer value followed the Slater-Pauling rule. The calculated half-metallic gaps are found for two systems. The three-dimensional plots of different mechanical moduli exhibit that the bulk modulus is isotropic, whereas Young's modulus, Poisson's ratio and shear modulus of both compounds are highly anisotropic. The effects of temperature and pressure on the heat capacity, thermal expansion coefficient and Debye temperature are also studied. [ABSTRACT FROM AUTHOR]

Management of high-risk prostate cancers is still a subject of debate, because of the lack of randomized trial comparing surgery and radiotherapy. If external beam radiotherapy is proposed, it must be associated with a long-term androgen deprivation therapy, at least 18-months. Irradiation of pelvic lymph nodes seems to improve distant metastasis-free survival and is so indicated in most of the cases. Moderate hypofractionation is not validated for pelvic lymph nodes irradiation. A combination of external beam radiotherapy and brachytherapy improved biochemical control in randomized trials without impact on survival. But this combination has been evaluated in large retrospective studies and seems to improve specific and overall survivals. An integrated boost on the MRI-defined index lesion is another way of dose escalation and improved also biochemical control. Stereotactic radiotherapy is not a validated option at this moment. For each patient, according to the extension of the disease, age, comorbidities and also his willingness, the best approach must be chosen, ideally in multidisciplinary meeting. [ABSTRACT FROM AUTHOR]

Abstract: First principles calculations have been performed within the framework of density functional theory to investigate the structural, electronic and thermodynamic properties of Sr x Cd1−x O ternary alloys. The exchange-correlation potential for structural properties was calculated by the standard local density approximation (LDA) and GGA (PBE), a more accurate nonempirical density functional generalized gradient approximation (GGA), as proposed by Wu and Cohen [Physical Review B 73 (2006) 235116], while for electronic properties, the Engel and Vosko GGA (EVGGA) and the modified Becke–Johnson (MBJ) of the exchange-correlation energy and potential, respectively, are used. Deviation of the lattice constants from Vegard's law and bulk modulus from linear concentration dependence (LCD) were observed for the ternary alloys. The MBJ band gaps values agree well with the available experimental results. In addition the thermodynamic stability of the alloys was investigated by calculating the critical temperatures of alloys. [Copyright &y& Elsevier]

Abstract: Density functional calculations are performed to study the structural and electronic properties of technologically important Pb1−x Ca x S y Se1−y quaternary alloys. The calculations are based on the total-energy calculations within the full-potential augmented plane-wave (FP-LAPW) method. For exchange-correlation energy and corresponding potential, the generalized gradient approximation (GGA) by Perdew–Burke–Ernzerhof (PBE) and Engel–Vosko (EVGGA) have been used. We investigated the effect of composition on lattice constant, bulk modulus and band gap for pseudobinary as well as for quaternary alloys, which showed non-linear dependence on the composition x and y. The presented contour maps of energy band gap and lattice constants versus concentrations could be useful for designing new structures with the desired optical properties. In addition, the energy band gap and natural band offset of simple cubic Pb1−x Ca x S y Se1−y quaternary alloys lattice matched to PbS and SrS substrates are investigated. The obtained results show that the quaternary alloys of interest could be appropriate materials for designing heterostructures with desired optical and interfacial properties. [Copyright &y& Elsevier]

On the basis of ab initio calculations employing density functional theory (DFT), we investigate the structural, electronic, optical and thermodynamic properties of two binaries: PbS and PbSe in rock-salt structures. In addition, several compositions with various ordered structures of PbS1-xSex alloys were studied. The calculations were performed using the full potential linearized augmented plane wave (FP-LAPW) method within the generalized gradient approximation (GGA). Various quantities, such as equilibrium lattice constants, bulk modulus, band structures and refractive index for all Se-concentrations are presented. The microscopic origins of the gap bowing were explained by using the approach of Zunger and coworkers. On the other hand, the thermodynamic stability of these alloys was investigated by calculating the excess enthalpy of mixing ΔHm as well as the phase diagram. [ABSTRACT FROM AUTHOR]

Abstract: Using first-principle method, we investigate the structural, electronic, optical and thermodynamic properties of the strontium semiconductors Pb1− x Sr x S with 25%, 50% and 75% of Sr. The calculations are performed by using the full-potential linearized augmented plane wave (FP-LAPW) method. As exchange–correlation potential we used the generalized gradient approximation (GGA) of Perdew et al. The variation of the calculated equilibrium lattice constant versus concentration shows that a small deviation from Vegard’s law is clearly visible with downward bowing parameter equal to 0.009Å. The bulk modulus as a function of x for Pb1− x Sr x S alloy shows a significant deviation from the linear concentration dependence (LCD) with downward bowing equal to 6.62GPa. The different roles of structural and chemical effects on the gap bowing and its variation with composition are identified and discussed. In addition, density of states and optical properties were calculated and compared to the available experimental data and previous theoretical works. On the other hand, the thermodynamic stability of these alloys was investigated by calculating the excess enthalpy of mixing ΔH m as well as the phase diagram. [ABSTRACT FROM AUTHOR]

Background: Pleural effusion is a common complication of cardiac surgery, but its characteristics and predisposing factors should be documented further. Our objective was to determine the prevalence, characteristics, and determinants of clinically significant pleural effusions, defined as those requiring therapeutic pleural drainage according to clinical assessment.Methods: The prevalence and characteristics of patients who had a pleural effusion within 30 days of undergoing coronary artery bypass graft, valve replacement, or both were analyzed retrospectively at our institution over a 2-year period.Results: Among the 2,892 patients included in the study (mean age, 66 years; men, 2,139), 192 patients (6.6%) had experienced a clinically significant pleural effusion in the 30 days postsurgery. These effusions occurred after a mean (+/- SD) duration of 6.6 +/- 5.9 days following interventions. Pleural fluid analysis was obtained in 114 patients (59.4%); all met the criteria for an exudate. Pleural fluid was hemorrhagic in 50% of cases. Age, body weight, baseline pulmonary function, and smoking status were similar between patients with and without effusion; however, the proportion of women; the number of patients with previous conditions of heart failure, atrial fibrillation, or peripheral vascular disease; and the number of patients receiving therapy with an anticoagulant or antiarrhythmic agent was higher in the pleural effusion group. Patients with pleural effusion had an increased prevalence of postoperative complications.Conclusions: Pleural effusion is a common complication of heart surgery, is associated with other postoperative complications, and is more frequent in women and in patients with associated cardiac or vascular comorbidities and medications used to treat those conditions.Trial Registration: ClinicalTrials.gov Identifier: NCT00665015. [ABSTRACT FROM AUTHOR]

Abstract: The structural, electronic and thermodynamic properties of the SrS1– x O x ternary mixed crystals have been studied using the ab initio full potential linearized augmented plane wave (FP-LAPW) method within density functional theory. The effect of composition on lattice parameter, bulk modulus and band gap was investigated. The lattice constants from Vegard''s law and the bulk modulus from linear concentration dependence were observed for the alloys. The microscopic origins of the gap bowing were explained by using the approach of Zunger and co-workers. The thermodynamic stability of these alloys was investigated by calculating the excess enthalpy of mixing as well as the phase diagram. In addition to FP-LAPW method, the composition dependence of the refractive index and the dielectric constant was studied by different models. [Copyright &y& Elsevier]

The electric-octupole E3 transition strengths from the first 3- state to the ground-state transition in sd shell even-even nuclei with A=16 to 40 are investigated within the shell model framework using the effective (0+1)ℏω PSDPF interaction. For this type of transition, new effective charges for protons and neutrons have been determined. Their values 1.36 e for protons and 0.48 e for neutrons are close to those obtained previously for electric-quadrupole E2 transitions in sd shell nuclei. The calculated E3 transition strengths from the 31-→0gs+ transitions are compared to a compilation of experimental E3 data for even-even nuclei throughout the sd shell. [ABSTRACT FROM AUTHOR]

Longtemps, la chimioradiothérapie adjuvante est restée incontournable dans la prise en charge thérapeutique des adénocarcinomes gastriques et pancréatiques. Pour ces tumeurs, l'exérèse chirurgicale, seul espoir d'offrir au patient une survie prolongée, n'est possible que dans 20 % des cas. La survie médiane des patients opérés n'est que de 12 à 20 mois en raison de la fréquence des récidives locorégionales et/ou métastatiques. Pour les cancers de l'estomac, la chimioradiothérapie adjuvante est justifiée par les résultats de l'essai de phase III de l'Intergroup 0116, publiés par MacDonald et al. Le gain de survie l'était au prix d'une toxicité non négligeable. Ce traitement a été supplanté au début des années 2000 par la chimiothérapie périopératoire. Actuellement, des essais de chimioradiothérapie néoadjuvante sont en cours dans le but d'améliorer l'observance et la tolérance des traitements. Pour les cancers du pancréas, le rôle de la chimioradiothérapie adjuvante est discuté depuis longtemps en raison d'essais aux résultats contradictoires. La radiothérapie néoadjuvante présente de nombreux avantages en termes d'efficacité et de tolérance. Elle augmente les chances de pouvoir réséquer ensuite la tumeur de manière complète. Plusieurs essais prospectifs sont en cours pour préciser sa place dans l'arsenal thérapeutique. For many years, adjuvant chemoradiotherapy remained essential in the therapeutic management of gastric and pancreatic adenocarcinomas. For these tumours, surgical excision, the only hope of offering the patient prolonged survival, is only possible in 20% of cases. The median survival of operated patients is only 12 to 20 months due to the frequency of locoregional and/or metastatic recurrences. For stomach cancers, adjuvant chemoradiotherapy is justified by the results of the phase III trial Intergroup 0116 published by MacDonald et al. The gain in survival was at the cost of significant toxicity. This treatment was supplanted in the early 2000s by perioperative chemotherapy. Currently, neoadjuvant chemoradiotherapy clinical studies are ongoing with the aim of improving treatments observance and tolerance. For pancreatic cancers, the role of adjuvant chemoradiotherapy has long been discussed because of trials with contradictory results. Neoadjuvant radiotherapy has many advantages in terms of efficacy and tolerance. It increases the chances of subsequent complete tumour resection. Several prospective trials are currently ongoing to clarify its place in the therapeutic arsenal. [ABSTRACT FROM AUTHOR]

The principal purpose of this work is to further the understanding of the structural, electronic, and thermodynamic properties of the SrxCa1-xS alloys (0≤ x ≤1) in Rock-salt phase using the full potential augmented plane wave (FP-LAPW) method within density functional theory. The exchange-correlation potential for structural properties was calculated by the standard local density approximation (LDA) and GGA (PBE) and the new form of GGA (WC) which is an improved form of the most popular Perdew-Burke-Ernzerhof (PBE), while for electronic properties, the alternative form of GGA modified by Becke-Johnson exchange correlation potential (MBJ) was also applied. It is shown that investigation on the effect of composition on lattice constant, bulk modulus, and band gap for ternary alloys shows almost nonlinear dependence on the composition. On the other hand, the thermodynamic stability of these alloys was investigated by calculating the excess enthalpy of mixing ΔHm as well as the phase diagram. (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

The structural, electronic and thermodynamic properties of Cd1−xCaxO ternary alloys are calculated using the first principles calculations performed within the framework of density functional theory. The exchange correlation potential for structural properties is calculated by the standard generalized gradient approximation (GGA) of Perdew et al., while for the electronic properties, the modified Becke-Johnson (MBJ) scheme is also applied. A deviation of the lattice constants from Vegard's law and bulk modulus from linear concentration dependence (LCD) are observed for the alloys. In addition, the thermodynamic stability of the alloys is investigated by calculating the critical temperatures of alloys. [ABSTRACT FROM AUTHOR]

Les carcinomes basocellulaires et les carcinomes épidermoïdes cutanés sont parmi les tumeurs cancéreuses les plus fréquentes dans le monde. Leur traitement repose le plus souvent sur leur exérèse chirurgicale. Une radiothérapie adjuvante peut être indiquée en cas de facteur de risque de récidive ou bien en alternative à la chirurgie si celle-ci n'est pas réalisable du fait du grand âge des patients, de leur comorbidité ou en alternative à une chirurgie potentiellement mutilante. La radiothérapie fait également partie de l'arsenal thérapeutique de tumeurs cutanées plus rares comme les tumeurs à cellules de Merkel, les lymphomes cutanés, la maladie de Kaposi et les carcinomes annexiels cutanés. Basal cell carcinomas and cutaneous squamous cell carcinomas are among the most common cancerous tumors in the world. Their treatment is most often based on surgery. Adjuvant radiotherapy may be indicated in case of risk factors for recurrence or as an alternative to surgery if surgery is not feasible due to the patient's advanced age and/or co-morbidities or as an alternative to potentially mutilating surgery. Radiotherapy is also part of the therapeutic arsenal for rarer skin tumors such as Merkel cell carcinoma, cutaneous lymphomas, Kaposi's disease and cutaneous adnexal carcinomas. [ABSTRACT FROM AUTHOR]

Résumé: Les métastases pinéales des tumeurs solides sont très rares. Le cancer primitif est généralement absent au moment du diagnostic de la métastase. Leur diagnostic est fait à l’IRM cérébrale, qui constitue l’examen clé. Notre travail se proposait de faire une revue de la littérature à propos de cette entité rare, en rapportant un cas de métastase pinéale d’un carcinome mammaire, colligé dans notre service. [ABSTRACT FROM AUTHOR]

Avec le chirurgien, le gastroentérologue et le médecin traitant, l'oncologue-radiothérapeute est impliqué dans le suivi post-thérapeutique des patients atteints d'un cancer du rectum traité par irradiation. Un suivi est recommandé par de nombreuses sociétés savantes ainsi que des groupes d'experts. Celui-ci consiste à réaliser un examen clinique, un dosage de l'antigène carcinoembryonnaire, une coloscopie et une scanographie thoraco-abdominopelvienne. Récemment trois essais randomisés ont montré le manque de bénéfice à réaliser une surveillance intensive par rapport à une surveillance minimale, en termes de survie globale. Cependant, la surveillance n'est pas seulement nécessaire pour détecter précocement une récidive de la maladie, elle permet également d'identifier et de traiter les complications/séquelles à long terme des traitements. Along with the surgeon, the gastroenterologist and the general practitioner, the radiation oncologist is involved in the follow-up of patients with rectal cancer treated by radiation. Post-treatment follow-up is recommended by major professional expert groups and consists of clinical examination, monitoring of carcinoembryonic antigen, colonoscopy and computed tomography of the abdomen and pelvis. Three recent large phase III randomized trials demonstrated a lack of survival benefit from intensive follow-up strategies in comparison with minimal follow-up. However, a follow-up program is not only important for the detection of an early disease relapse but it can be also used for the identification and the management of long-term toxicity and sequalae related to rectal cancer treatment. [ABSTRACT FROM AUTHOR]

The first principles calculations of structural and magnetic properties of the Heusler material Mn2NiAl, have been studied using a full potential linearized augmented plane wave (FP-LAPW) within the density-functional theory (DFT). The phase stability of the cubic austenitic (L21) structure for Mn2NiAl in both Cu2MnAl (Fm3 m space group) and Hg2CuTi (F43 m space group) type of structures with ferromagnetic and antiferromagnetic states, has been treated by applying the generalized gradient approximation proposed by Wu and Cohen (WC-GGA) alongside with the martensitic structure of Mn2NiAl. The analysis of phase stability, cohesive energy and the calculated formation enthalpy of Mn2NiAl reveal that the ferromagnetic MnMnNiAl is the most stable type of structure. Moreover, the calculated lattice parameters are found to be in good agreement with theoretical data. The variation of total magnetic moments MT(μB), MMn (μB), MNi (μB) and MAl (μB) in Mn2NiAl with pressure at varying temperature (0, 273 and 344 K), have been calculated. [ABSTRACT FROM AUTHOR]

Structural, electronic, magnetic and thermodynamic main features for Ni1-xTixO ternary alloys in rock-salt structure with Ti content in the range 0≤x≤1 were studied using the full potential Linearized augmented plane wave (FP-LAPW) method within density functional theory. The exchangecorrelation potential was calculated by the generalized gradient approximation. The analysis of the electronic density of states curves allowed the computation of the magnetic moments which are considered to lie along (010) axes. The thermodynamic stability of this alloy was investigated by calculating the excess enthalpy of mixing ΔHm as well as the phase diagram. In addition, the Monte Carlo simulations have been exploited to calculate the transition temperature and magnetic coercive field in the alloy. [ABSTRACT FROM AUTHOR]

Structural, electronic, optical and thermodynamic properties of the SrTeO alloys (0 ≤ x ≤ 1) in rock-salt phase are calculated using the full potential-linearized augmented plane wave (FP-LAPW) method within density functional theory. The exchange-correlation potential for structural properties was calculated by the standard local density approximation (LDA) and GGA (PBE) and the new form of GGA (WC) which is an improved form of the most popular Perdew-Burke-Ernzerhof (PBE), while for electronic properties, in addition to LDA, GGA corrections; Engel-Vosko GGA (EV-GGA) and modified Becke-Johnson (mBJ) schemes were also applied. The results show that the use of GGA (WC) in our calculations is more appropriate than GGA and LDA and gives a good description of structural properties such as lattice parameters and bulk modulus. Our investigation on the effect of composition on lattice constant, bulk modulus and band gap for ternary alloys shows almost nonlinear dependence on the composition. In addition to FP-LAPW method, the composition dependence of the refractive index and the dielectric constant was studied by different models. On the other hand, the thermodynamic stability of this alloy was investigated by calculating the excess enthalpy of mixing Δ H as well as the phase diagram. [ABSTRACT FROM AUTHOR]

Abstract: The ionic conductivity of 4 and 9mol% yttria-doped zirconia nanomaterials (noted, respectively, N4 and N9), of 9.5mol% yttria-doped zirconia single crystal (noted YSZ) and of a nanocomposite with 2mol% alumina noted (NC2) was studied using the impedance spectroscopy technique. In this study, our aim was to find optimal conditions for any improvement of ionic conductivity at low temperatures. Experimental results showed that the total ionic conductivity of N4 is higher than that for YSZ single crystals and this for the most part of the temperature range studied (300–500°C). Comparing N4 with N9, the former exhibited the highest conductivity for the “grain contribution” but not for the “grain boundary contribution”. For the nanocomposites NC2, we found a slight increase of the ionic conductivity even at low temperatures compared to the nanomaterial of same yttria content. This work has shown that the conductivity in these materials depends not only on the alumina content but also on the microstructure. [Copyright &y& Elsevier]