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Ab initio density functional theory is employed to investigate the structural, elastic, electronic and optical properties of the half-Heusler NaScSi alloy. The lattice constants are very near to the available theoretical data. In addition, besides the GGA approximation, the modified Becke–Johnson exchange potential is also used to improve the direct X→X band gap value. Furthermore, the elastic constants and related elastic moduli confirm its stability and brittle behaviour in the type I structure. The influence of pressure on Cij constants, bulk modulus B, Cauchy pressure, Poisson ratio ν, shear modulus, B/G ratio and anisotropy factor A are analysed. Additionally, the strong absorption is extended between the visible domain and that of the ultraviolet is predicted.

A systematic theoretical investigation is carried out on the possible piezoelectric effect in the half-Heusler FeVX (X = P, As, Sb) compounds crystallizing in the cubic MgAgAs-type structure C1b by combining density functional theory (DFT) and perturbation theory (DFPT) based on the pseudopotential plane wave (PP-PW) method implemented in the ABINIT code. The ground-state properties such as the lattice constants, and the bulk modulus and its pressure derivative are obtained using both the local density approximation and the generalized gradient approximation for the exchange–correlation functional, and the results are compared with other studies. The results for the electronic properties reveal that all the compounds exhibit semiconducting behavior with a narrow indirect bandgap. In addition, the elastic, dielectric, and piezoelectric constants are computed using density functional perturbation theory. The title compounds are found to exhibit a good electromechanical coupling coefficient (k14). No experimental or theoretical data are available for their piezoelectric properties. Thus, the results of this study can be considered to represent theoretical predictions of the properties of new piezoelectric half-Heusler compounds that can be selected based on the values of their piezoelectric coefficient (e14), which are greater than the value of 0.16 C/m2 measured empirically for GaAs. Finally, the results presented herein shed light on the use of such piezoelectricity as a possible effect in various applications such as micromechanical actuators, sensors, and self-powered devices.

Structural, electronic, elastic, and transport properties of FeVX (X = As, P) half-Heusler (HH) compounds have been calculated using density functional theory (DFT). The generalized gradient approximation developed by Perdew–Burke–Ernzerhof (GGA-PBE) is utilized for the calculation of the structural properties and the mechanical parameters of FeVX (X = As, P), indicating that the studied compounds are mechanically stable. The Tran and Blaha-modified Becke–Johnson potential (TB-mBJ) is utilized to improve the investigation of the electronic structure and also indicates that the FeVX (X = As, P) compounds are narrow-gap semiconductors. Calculations of transport efficiency are performed using the semiclassical Boltzmann theory. The figure of merit ZT is near unity at room temperature, indicating that both compounds are good candidates for use in transport devices.

Des calculs de theorie de la fonctionnelle de la densite (DFT) ont ete effectues pour obtenir des geometries optimisees, les energies orbitales moleculaires occupees les plus basses (HOMO), les ene...

The structural, electronic, elastic and magnetic properties of CoCrScIn were investigated using first principle calculations with applying the full-potential linearized augmented plane waves (FP-LAPW) method, based totally on the density functional theory (DFT). After evaluating the results, the calculated structural parameters reveal that CoCrScIn compound is stable in its ferrimagnetic configuration of the type-III structure. The mechanical properties show its brittle and stiffer behavior. The formation energy value showed that CoCrScIn can be experimentally synthesized. Additionally, the obtained band structures and density of states (DOS) reflect the half-metallic behavior of CoCrScIn, with an indirect bandgap of 0.43[Formula: see text]eV. The total magnetic moment of 3[Formula: see text][Formula: see text] and half-metallic ferrimagnetic state are maintained in the range 5.73–6,79 Å. The magnetic moment especially issues from the Cr-[Formula: see text] and Co-[Formula: see text] spin-polarizations. Furthermore, the calculations of Curie temperature reveal that CoCrScIn has high magnetic transition temperature of 836.7[Formula: see text]K.

First-principles calculations, based on the density functional theory (DFT), have been used to predict the structural, elastic, electronic and magnetic properties of XMg3O4 (X = Li, Na, K and Rb) compounds. They have been performed by employing the full-potential linearized augmented plane wave method (FP-LAPW), as implemented in Wien2k code. It was found that all compounds were ferromagnetic by energy minimization procedure. The computations of elastic constants show that our compounds are mechanically stable. The electronic properties, through the density of states and band structures, indicate that these compounds exhibit half-metallic nature, and the spin up band gaps (HMgaps) were found to be5.32 (0.18) eV, 4.49 (0.28) eV, 3.01 (0.38) eV and 1.53 (0.17) eV for LiMg3O4, NaMg3O4, KMg3O4 and RbMg3O4, respectively. In addition, for all compounds, the calculated integer magnetic moment value of 1.0 µB fulfills the necessary condition of the half-metallicity. The calculated Curie temperatures $${T}_{c}$$ are 537, 365, 260 and 113 K for LiMg3O4, NaMg3O4, KMg3O4 and RbMg3O4, respectively.

The full-potential linearized augmented plane waves (FP-LAPW) method, within the density functional theory (DFT), has been used to investigate the structural and elastic properties of KRbAs, KNaAs and NaRbAs. The obtained results, utilizing the generalized gradient approximation (GGA), revealed that all compounds prefer their type-I structure ferromagnetic (FM) phase. However, only two among them, KRbAs and KNaAs, exhibit a mechanical stability thus the electronic and magnetic properties have been calculated for both compounds. In the electronic properties, we found that both compounds show a half-metallic character with direct gaps of 1.114[Formula: see text]eV and 1.514[Formula: see text]eV, in the spin-up channel, for KNaAs and KRbAs, respectively. Thus, they may be potential candidates for spin injection in the field of spintronic applications. Moreover, their integer calculated total magnetic moment of [Formula: see text] agrees with the Slater–Pauling rule.

In this paper, the full potential linearized augmented plane wave method implemented in the WIEN2K code with first principles-based density functional theory are used to investigate the structural, elastic, electronic and thermoelectric properties of TaCoSn, TaIrSn and TaRhSn. The structural and elastic constants are calculated using the generalized gradient potential developed by Perdew-Burke-Ernzerhof (GGA-PBEsol). The electronic structures are performed by means of GGA-PBEsol and improved by TranBlaha modified Becke-Johnson (TB-mBJ) potential. Our results show that the studied compounds are semiconductors with indirect gaps. On the other hand, we investigated the thermoelectric properties at different temperatures with respect to the chemical potential. The results show that the thermopower factors are more important for p-type doping than those for n-type doping and the maximum value of these factors indicates the optimal hole-doping level which gives rise to high thermoelectric performances of these materials. Finally, we note that the best thermopower values are found for the TaRhSn compound with optimal doping levels of (75.76, 175.60 and 238.92) x 1014 µW cm – 1 K – 2 s – 1 at temperatures of 300, 600, and 900 K, respectively.

Full-Heuslers are a group of materials that have repeatedly attracted the curiosity of scientists and researchers, especially for their use in the field of spintronics. In this work, we undertook a study on the structural, elastic, electronic, magnetic and thermodynamic properties of the full-Heusler Mn2OsGe alloy using the calculations of the first principles. Two approximations are used: the generalized approximation of the Perdew–Burke–Ernzerhof GGA–PBE gradient for electron-correlation exchange and the new modified Tran-Blaha form of the modified Becke-Johnson mBJ–GGA-PBE potential. As important results, we found that the compound Mn2OsGe is stable in the CuHg2Ti structure; on the other hand, we could also verify its mechanical stability at zero temperature and pressure. For the calculation of the electronic properties, we were able to determine the half-metallic ferrimagnetic character of our compound, which exhibits a metallic behavior in the state of the majority spins, and a semiconductor behavior in the state of the minority spins. An integer value of 2[Formula: see text][Formula: see text] has been recorded for a magnetic moment and this conforms to the Slater–Pauling rule.

The study of the structural, mechanical, and magneto-elctronic properties of TiZrIrZ (Z = Al, Ga, In) quaternary Heusler alloys was performed using full-potential linearized augmented plane-wave (FP-LAPW) method, based on the density functional theory (DFT) with generalized gradient approximation (GGA). The findings show that the ferromagnetic phase of Type I atomic arrangement is energetically favorable. The calculated spin-polarized band structures of TiZrIrZ (Z = Al, Ga, and In) reveal that they are half-metallic materials, with indirect band gaps (half-metallic gaps) of 1.01(0.41 eV), 0.96(0.37 eV), and 0.91 (0.43 eV) in the minority spin channel, respectively. The ferromagnetism of TiZrIrZ alloys is caused by the d-orbitals of Ti and Zr atoms and the total magnetic moments verify the Slater–Pauling rule: $$M_{t} = Z_{t} - 18$$. The calculated Curie temperatures of TiZrIrZ (Z = Al, Ga, and In) are 545 K, 566 K, and 574 K, respectively. Moreover, the half-metallicity of all these alloys is kept by the volumetric strain and tetragonal deformation in the relatively large ranges, for the lattice parameter and c/a ratio, respectively.

The aim of the present study was to assess two methods of mass abdominal closure with the fishing line as an alternative suture material for abdominal wall closure. Eighteen healthy male white rabbits weighing approximately 2.5 kg were used in this study. Animals were separated into three groups: control group (CG) (n = 06), interrupted pattern suture experimental group (IEG) (n = 06), and continuous pattern suture experimental group (CEG) (n = 06). Incisional wounds (4 cm) were performed in the right flank of abdominal wall. In control group (CG), the abdominal muscles and peritoneum were sutured in one layer with simple interrupted pattern using PGA resorbable suture and the skin with commercial synthetic suture (nylon). Then, in experimental groups, closure of peritoneum, abdominal muscles, and skin was performed with one-layer pattern using translucent nylon fishing line. Daily scores were allocated for signs of infection, wound healing, and wound adhesion. A faster wound closure time was recorded in control group (9 days) compared to experimental groups (13 days). All study animals showed low adhesion scores that were very important in the muscular wall. Almost similar histopathology profiles were observed in all groups. This study has demonstrated that fishing line, as suture material, is suitable for mass abdominal closure in rabbit model.

The structural, electronic, elastic, and thermoelectric properties of TiIrX (X = As and Sb) half-Heusler compounds with 18 valence electrons were studied using density functional theory. The generalized gradient approximation of Perdew–Burke and Ernzerhof used for calculation of the structural parameters and elastic properties of TiIrAs and TiIrSb denotes that the computed lattice constants were in excellent agreement with the available experimental data and previous theoretical works. Furthermore, the calculated elastic constants for both compounds satisfy the Born criteria indicating their mechanical stabilities. The modified Becke–Johnson potential (TB-mBJ) was used to provide a better description of the electronic structures, which indicate that both compounds are narrow-gap semiconductors. Additionally, the investigations of thermoelectric performance were carried out using the results of ab initio band-structure calculations and the semi-classical Boltzmann theory within the constant relaxation time approximations. The predicted values of the figure of merit ZT e are close to unity at room temperature. This reveals that TiIrAs and TiIrSb compounds are excellent candidates for practical applications in the thermoelectric devices.

We have systematically investigated the structural, electronic, optical and thermoelectric properties of HfIrX (X = As, Sb and Bi) belonging to the 18 valence electron ABX family using first-principles density functional theory calculations. In the first phase, the structural parameters of HfIrX (X = As, Sb and Bi) in the cubic LiAlSi-type (F-43 m) structure such as the lattice parameters, the bulk modulus (B) and their pressure derivative $$(B^\prime )$$ are calculated using the full-potential linearized augmented plane wave method within the generalized gradient approximation GGA-PBEsol. In the second phase, investigations of electronic and optical properties were treated by the TB-mBJ exchange-correlation potentials. The third phase is devoted to the interpretation and prediction of the thermoelectric performance of our compounds by combining the results of ab initio band structure calculations and Boltzmann transport theory in conjunction with rigid band and constant relaxation time ( $$\tau )$$ approximations as incorporated in the BoltzTraP code. We note that, because of the existence of heavy elements in our compounds, spin–orbit coupling is added for both electronic and thermoelectric calculations in order to test the effect of spin–orbit interaction on these properties. Our results are compared with other theoretical and experimental data and provide guidance for practical applications in the fields of optoelectronics and thermoelectrics.

Background:Malondialdehyde (MDA) is a highly reactive compound generated during lipid-peroxidation in conditions associated with oxidative stress. MDA can irreversibly modify proteins (e.g. lysine, arginine and histidine residues). In addition, acetaldehyde can further react with MDA adducts to form malondialdehyde-acetaldehyde (MAA) modification. Such protein modifications can lead to immunogenic neo-epitopes that are recognized by autoantibodies. In fact, anti-MDA/MAA IgG antibodies are significantly increased in the serum of patients with autoimmune diseases, such as rheumatoid arthritis (RA) (1). Interestingly, anti-MDA/MAA antibodies have been shown to promote osteoclast (OC) differentiation in vitro suggesting a potential role for these autoantibodies in bone damage associated with RA (1).Objectives:Little is known about the molecular mechanisms activated by autoantibodies in RA. Here, we elucidate the pathways specifically triggered by anti-MDA/MAA autoantibodies in developing osteoclasts.Methods:Recombinant human monoclonal anti-MDA/MAA antibodies, which were previously cloned from single synovial B cells of RA patients, were added to different OC assays. OCs were generated from monocyte-derived macrophages in the presence of the cytokines RANK-L and M-CSF. OC development was monitored by light microscopy following tartrate-resistant acid phosphatase staining and by erosion assays using calcium phosphate-coated plates. Bone morphometrics were studied in anti-MDA/MAA-injected mice using X-ray microscopy. Cellular metabolism was analyzed by mass spectrometry, Seahorse XF Analyzer and a colorimetric L-Lactate assay.Results:Anti-MDA/MAA antibodies induced a robust OC differentiation in vitro and bone loss in vivo. The anti-MDA/MAA antibodies acted on developing OCs by increasing glycolysis via an Fcγ receptor I-mediated pathway and the upregulation of the transcription factors HIF-1α, Myc and CHREBP. Such regulation of cellular metabolism was exclusively observed in the presence of the osteoclastogenic anti-MDA/MAA clones, whereas other RA-associated autoantibodies (anti-MDA/MAA or anti-citrullinated protein antibodies) had no effect on metabolism. The anti-MDA/MAA treatment induced a shift in the tricarboxylic acid (TCA) cycle activity in developing OCs, leading to the accumulation of citrate and aconitate.Conclusion:We described a novel type of autoantibody-induced pathway in RA, which might contribute to increased OC activation and a consequent bone loss. Anti-MDA/MAA antibodies promoted osteoclast development by increasing glycolysis and by modulating the TCA cycle through a signaling pathway that included Fcγ receptor I and a network of transcription factors acting on glycolysis. A TCA cycle bias towards citrate production suggests that the anti-MDA/MAA antibodies might stimulate OCs via increasing lipid biosynthesis in the cells.References:[1]Grönwall C. et al. J. Autoimmunity 84 (2017): 29-45.Acknowledgements:This Project has received funding from FOREUM, Foundation for Research in Rheumatology, from the European Research Council (ERC) grant agreement CoG 2017 - 7722209_PREVENT RA, the EU/EFPIA Innovative Medicine Initiative grant agreement 777357_RTCure, the Konung Gustaf V:s och Drottning Victorias Frimurarestiftelse and Knut and Alice Wallenberg Foundation.Disclosure of Interests:Koji Sakuraba: None declared, Akilan Krishnamurthy: None declared, Alexandra Circiumaru: None declared, Vijay Joshua: None declared, Heidi Wähämaa: None declared, Marianne Engström: None declared, Meng Sun: None declared, Xiaowei Zheng: None declared, Cheng Xu: None declared, Khaled Amara: None declared, Vivianne Malmström Grant/research support from: collaboration with Pfizer, unrelated to the abstract, Sergiu-Bogdan Catrina: None declared, Caroline Grönwall: None declared, Bence Réthi: None declared, Anca Catrina Grant/research support from: collaboration with BMS and Pfizer, unrelated to the present abstract

We use the first-principles-based density functional theory with full potential linearized augmented plane wave method to investigate the structural, elastic, electronic, and thermoelectric properties of ZrIrAs, ZrIrBi, and ZrIrSb. The calculated structural and elastic constants with generalized gradient potential developed by Perdew---Burke---Ernzerhof (GGA-PBEsol) reveal that our compounds are stable in the cubic LiAlSi-type structure. The electronic structures are calculated with GGA-PBEsol and improved by Tran---Blaha modified Becke---Johnson (TB-mBJ) potential. The thermoelectric properties were determined at temperatures of 300, 600, and 800 K with respect to the p-type and n-type doping levels. We find that the thermopower factors are larger for p-type doping, implying that the hole doping provides more enhancement of thermoelectric performances in ZrIrAs, ZrIrBi, and ZrIrSb. Among them, the best thermopower values were found for the ZrIrAs compound with optimal doping levels of 46.17, 133.05, and 185.92 $$\times 1014\,\upmu \hbox {W}\, \mathrm{cm}^{-1}\; \hbox {K}^{-2}\;\hbox {s}^{-1}$$?1014μWcm-1K-2s-1 at temperatures of 300, 600, and 800 K, respectively.

We have investigated the structural properties of seven different structure types of Mg2Si which include the cubic CaF2, orthorhombic PbCl2, hexagonal Ni2In, tetragonal Al2Cu, Laves phase (cubic MgCu2), hexagonal MgZn2 and dihexagonal MgNi2 type of structures, using a full potential linearized augmented plane wave method as implemented in WIEN2k within the framework of density functional theory. The exchange–correlation potential is treated by the new form of generalized gradient approximation (GGA-PBEsol). In total energy calculations it is clearly seen that cubic CaF2-type structure is stable at ambient conditions, and it undergoes a first-order phase transition to orthorhombic PbCl2-type, then to the hexagonal Ni2In-type structure and finally to the cubic Laves phase MgCu2-type. A new structure type is predicted to be stable at high pressure. Moreover, we intend to combine the electronic structure calculations performed by mean of generalized gradient approximation and modified Becke–Johnson potential with Boltzmann transport theory as incorporated in BoltzTraP code to interpret and predict the thermoelectric performance of each stable phase as a function of the chemical potential at various temperatures. We find a high thermoelectric thermopower values in cubic CaF2-type structure that could promise an excellent candidate for potential thermoelectric applications.

In this paper, we present the study of the structural, mechanical, magneto-electronic and thermodynamic properties of the perovskite KBeO3. The calculations were performed by the full potential augmented plane wave method, implemented in the WIEN2k code which is based on density functional theory, using generalized gradient approximation. The computed formation energy and elastic constants indicate the synthesizability and mechanical stability of KBeO3. Moreover, our results showed that the latter is a half-metallic material with half-metallic gap of 0.67 eV and an integer magnetic moment of 3μB per unit cell. In addition, KBeO3 maintains the half-metallic character under the pressure up to about 97 GPa corresponding to the predicted magnetic-phase transition pressure from ferromagnetic to non-magnetic state. The volume ratio V/V0, bulk modulus, heat capacity, thermal expansion and the Debye temperature are analyzed using the quasi-harmonic Debye model.

This paper concerns a predictive investigation of the structural and elastic stability, electronic structure, and thermoelectric properties of CoVX (Ge and Si) Half-Heusler materials. The structural constants and mechanical stability are computed utilizing the (GGA-PBE) approximation. The computed lattice constants of CoVX (Ge and Si) compounds are in good accordance with other theoretical reports. Furthermore, the mechanical parameters and the related elastic constants reveal that CoVX (Ge and Si) alloys are mechanically stable and ductile. To ameliorate the computation of the energy band gap, the (TB-mBJ) method was employed. It is shown that the CoVX (Ge and Si) compounds are an indirect band-gap semiconductors. At room temperature, the computed figure of merit of CoVGe and CoVSi compounds is about unity, which denote that the CoVGe and CoVSi compounds have good thermoelectric performance and can be applied for the production of electricity in the transport devices.

We investigate the structural, electronic, magnetic and elastic properties of KMgO3, by using first principle calculations, applying the full-potential linearized augmented plane waves (FP-LAPW) method based totally on functional density theory (DFT), using Generalized Gradient Approximation (GGA) and modified Beck Johnson TB-mBJ potential in exchange correlation term. After analyzing the obtained structural parameters, the results revealed that KMgO3 compound is most stable in its ferromagnetic configuration. The formation energy value showed that this compound can be experimentally synthesized. Furthermore, the calculated band structures, and density of states (DOSs) indicate the half-metallic behavior of KMgO3. We found also that the total magnetic moment is an integer value of 3μB which confirms the half-metallic character. The evaluation of Curie temperature of KMgO3 compound is determined within the mean field approximation (MFA), and equals 560.4 K. The magnetic moment mainly originates from the spin-polarization of p electrons of O atoms.

Soil organic carbon fractions reflect the difference in soil organic carbon from one land use to another, and it can be regarded as an indication of the degree of soil organic carbon deterioration or improvement. Although knowledge of importance soil quality indicators is vital for replenishing and ma intaining soil fertility, little information is available on the effect of different land use management on soil organic matte r fractions in Sierra Leone. In the present study, th e effects of different land use on the distribution of soil orga nic matter fractions in soils of the Njala series was assessed . The study revealed both positive and negative effect of land uses on Organic carbon fractions at the Matturie site showe d an increase upon conversion of grassland to tree cropp ing except for carbon in the silt+clay fraction. The to tal organic carbon, light fraction carbon and particula te organic carbon fractions were significantly greater in the forest soil than in soils under grassland. The decl ine in the silt+clay fraction organic carbon was an indication that residue decomposition and organic matter addition a re low in this area. At the Old Agronomy Site, where Acac ia and Gliricidia fallows were converted to agriculture (groundnut), soil organic carbon (SOC) contents sho wed a decrease under annual cropping land use types. The conversion of Acacia and Gliricidia land use to gro undnut cultivation resulted in loss of total organic carbo n and all carbon fractions. The largest decline was in the li ght fraction carbon (16.46%)., followed by the particul ate organic carbon (15.82%), total organic carbon (14.6 3%) and the silt+clay fraction (5.83%). The least decli ne occurring in the silt+clay fraction indicates that organic matter is better protected in silt+clay fraction. S imilar changes in soil organic carbon fractions, as observ ed for the Old Agronomy site, were observed at the NATC si te. The results showed that there are greater losses of particulate organic carbon (17.24%), light fraction s (18%) and total organic carbon (16.21) than from the silt +clay fraction (7.34) when the land use is changed from secondary forest to arable cropping.

The main aim of this study was to assess the soils of Bogur microwatershed in Northern Transition Zone of Karnataka for sustainable production of maize and paddy. Seven land qualities including water availability index (W), oxygen availability (O), nutrient availability index (NAI), water retention (I), rooting conditions (R), excess of salts (Sa) and topography (T) were selected and their suitability evaluated. Four soils series: Singhanhalli, Bogur, Mugli and Venkatapur and seventeen soil units including SGH-c-d4-Be1 belonging to Singhanhalli series; MGL-cl-d3-De2 belonging to Mugli series; BGR1-sl-d4-Ce2, BGR2-c-d5-Be1, BGR3-sl-d4-Ce3 and BGR4-cl-d5-Ce2 belonging to Bogur series; and VKP1-sc-d4-Ce2, VKP2-sl-d3-Ee4, VKP3-c-d5-Be1, VKP4-sl-d2-Be1, VKP5-scl-d4-De3, VKP5-scl-d3-De2, Vkp5-scl-d4-Be2, VKP5-scl-d3-Ce2, VKP6-cl-d4-Ce2, VKP7-sl-d2-De3, and VKP8-sl-d4-De3 belonging to Venkatapur series, were identified. Singhanhalli series covers 78.5 ha (10.3%); Mugli series covers 22.1 ha (2.9%); Bogur series covers 237.3 ha (31.2%); and Venkatapur series covers 406.6 ha (53.5%). One mapping unit, VKP2-sl-d3-Ee4 which accounts for 10.2 ha (1.3%) of the study area, was not evaluated for crop production because it is a non-cultivable land. The results revealed that 33.8 ha (4.4%) is moderately suitable, 312.7 ha (41.1%) is marginally suitable and 387.7 ha (51%) is not suitable for maize; whereas for paddy, all sixteen mapping units which account for about 734.2 ha (96.5%) of study area is marginally suitable. These results could be used as baseline information needed for mapping specific soil resource constraints for sustainable production of these crops in the study area.

Half-metallic properties of new predicted Mn 2 -based full Heusler alloys Mn 2 ZrSi and Mn 2 ZrGe have been studied by first-principles full-potential linearized augmented plane wave plus local orbital (FP-LAPW+lo) method based on density functional theory (DFT). Our investigation is focused on the structural, elastic, electronic and magnetic properties of these compounds. The AlCu 2 Mn-type structure is found to be energetically more favorable than the CuHg 2 Ti-type structure for both compounds and are half-metallic ferrimagnets (HMFIs) with total magnetic moments of 2.000 µ B per formula unit, well consistent with Slater–Pauling rule ( M tot =(24– Z tot ) µ B ). Calculations show that both the alloys have an indirect band gaps, in the majority-spin channel, with values of 0.505 eV and 0.278 eV for Mn 2 ZrSi and Mn 2 ZrGe, respectively. It was found that Mn 2 ZrSi and Mn 2 ZrGe preserved their half-metallicity for lattice constants range of 5.85–6.38 A and 6.05–6.38 A, respectively, and kept a 100% of spin polarization at the Fermi level. Moreover, the calculated formation energies and elastic constants confirm that these compounds are stable chemically and mechanically, and the good crystallographic compatibility with the lattice of semiconductors used industrially makes them promising magnetic materials in spintronic applications.

This study reports on the structural, mechanical and magneto-electronic properties for new perovskite compound LiBeO3. In this paper, the Full Potential Linearized Augmented Plane Wave method is used to investigate these properties. The structural optimization reveals that its ferromagnetic state is more stable than those of the non-magnetic and anti-ferromagnetic phases. The calculated elastic constants and formation energy indicate that LiBeO3 is mechanically stable and experimentally synthesizable, respectively. Around the Fermi energy, the main contribution to the total DOS is due to O-p states. The studied compound is ferromagnetic half-metal with a large band gap of 7.73 eV in the spin-up channel, originated mainly by an energetic downshift of O-p orbital in this spin-direction. The calculated total magnetic moment is an integer value of 3 μB, which confirms the half-metallic character of LiBeO3. It is also characterized by a Curie temperature of 823 K, computed using mean field theory. Moreover, the half-metallicity is maintained under the pressure up to a value of 24.7 GPa. To the best of our knowledge, LiBeO3 is the first investigated half-metallic perovskite without a transition metal.

In this work, we present a study of the structural, elastic and electronic properties of the cubic antiperovskites XNMg3 (X = P, As, Sb and Bi) using the full-potential augmented plane wave plus local orbital (FP-LAPW + lo) within the generalized gradient approximation based on PBEsol, Perdew 2008 functional. We determined the lattice parameters, the bulk modulus B and their pressure derivative B′. In addition, the elastic properties such as elastic constants (C11, C12 and C44), the shear modulus G, the Young modulus E, the Poisson’s ratio ν and the B/G ratio are also given. For the band structure, density of states and charge density the exchange and correlation effects were treated by the Tran-Blaha modified Becke-Johnson potential to prevent the shortcoming of the underestimation of the energy gaps in both LDA and GGA approximations. The obtained results are compared to available experimental data and to other theoretical calculations.

We study the structural, elastic and electronic properties of perovskite insulator LaAlO3 using two different methods: the full-potential linearized augmented plane wave method and the pseudo-potential plane wave scheme in the frame of generalized gradient approximation and local density approximation GGA + mBJ. We have evaluated the ground state quantities. Also, we have presented the results of the band structure and densities of states. These results are in favourable agreement with previous theoretical works and the existing experimental data. To complete the fundamental characteristics of this compound, we have analyzed the thermodynamic properties.

The structural, mechanical, electronic, and transport properties of RuVX (As, P, and Sb) Half-Heusler compounds are studied. The density functional theory (DFT) based on full-potential linearized augmented plane wave FP-LAPW method as integrated in the Wien2k code was used. The structural properties and mechanical parameters are carried out by mean of the generalized gradient approximation (GGA-PBEsol). The computed lattice parameters are in good accordance with the experimental data and other theoretical reports. In Addition, the elastic constants and the related elastic moduli indicate that RuVX (As, P, and Sb) compounds are ductile and mechanically stable in the cubic phase. The modified Becke–Johnson potential (TB-mBJ) was applied to enhance the calculation of the electronic properties. It is found that the RuVX (As, P, and Sb) compounds are semiconductors with an indirect band-gap. GGA + U calculations are performed to investigate the relationship between band gap and Hubbard potential. Studies of thermoelectric properties were performed by the Boltzmann transport equations as incorporated in BoltzTraP code. At room temperature, the obtained values of the figure of merit (ZT) for RuVAs, RuVP, and RuVSb compounds are around unity, which confirm that all compounds have good transport efficiency and can be utilized for electricity production and thermoelectric devices.

Structural, elastic, and electronic properties of orthorhombic Pbnm CaTiO 3 are studied using both full potential linearized augmented plane wave (FP-LAPW) and plane-wave pseudopotential (PW-PP) methods. Exchange–correlation effects are treated by the generalized gradient approximation (GGA). The equilibrium lattice constants, the bulk modulus, its pressure derivative, and the electronic structure are in good agreement with other calculations and with experimental data. For elastic constants, Young modulus, and Poisson ratio, to our knowledge, no data are available in literature for comparison. In addition, pressure and temperature effects on the volume cell, the bulk modulus, the heat capacity, and the thermal expansion coefficient are investigated in the 0–28 GPa pressure range and in the 0–1200 K temperature range.

In this paper, we study the structural, elastic and electronic properties of perovskite LaAlO3 using two different methods: the full-potential linearized augmented plane wave (FP-LAPW) method and the pseudopotential plane wave (PP-PW) scheme in the frame of generalized gradient approximation (GGA). We have evaluated the ground-state quantities such as lattice parameter, bulk modulus and its pressure derivative as well as the elastic constants. Also, we have presented the results of the band structure, densities of states and charge densities. These results were in favourable agreement with previous theoretical works and the existing experimental data. To complete the fundamental characteristics of this compound we have analyzed the thermodynamic properties using the quasi-harmonic Debye model.

In this Letter, we study the structural, elastic and electronic properties of perovskite semiconductor SrTiO 3 using two different methods: the full-potential linearized augmented plane wave (FP-LAPW) method and the pseudo-potential plane wave (PP-PW) scheme in the frame of generalized gradient approximation (GGA). We have evaluated the ground state quantities such as lattice parameter, bulk modulus and its pressure derivative as well as the elastic constants. Also, we have presented the results of the band structure, densities of states and charge densities. These results were in favourable agreement with previous theoretical works and the existing experimental data. To complete the fundamental characteristics of this compound we have analyzed the thermodynamic properties such as thermal expansion coefficient, and specific heats in the whole pressure range from 0 to 20 GPa and temperature range from 0 to 1200 K.

We present the molecular dynamics simulations results of the structural and dynamical properties of the zinc-blende BBi over a wide range of temperature (400–1500 K). Our simulations were carried out using the three-body Tersoff potential, which accurately reproduces the lattice and elastic constants of the BBi. A good agreement was found between our calculated results and the available theoretical data of the lattice constant, bulk modulus and the cohesive energy. Our study enabled us to predict the thermodynamic properties like the specific heat and the lattice thermal expansion. We have also applied this computational method to check its transferability to predict the phase transition for this compound. In particular, the transition pressure to the rock-salt phase is calculated and the results are compared with other work.

By employing the first-principles method of the full potential linear augmented plane waves (FPLAPW), the structural, elastic and the electronic properties of LaBi are investigated. It is found that this compound has a semiconducting small and indirect gap. Through the quasi-harmonic Debye model, in which the phononic effects are considered, we have obtained successfully the thermodynamic properties such as thermal expansion coefficient, Debye temperature and specific heats in the whole pressure range from 0 to 10 GPa and temperature range from 0 to 1600 K.

Dirofilariasis is a zoonosis affecting dogs and cats. It was transmitted to man by mosquito bites. Human dirofilariasis is rare. We report a case of 4-year-old girl presented with a subcutaneous palmar nodule of the hand. Surgical excision shows a nodule encircling the forth flexor tendon. The histological examination established the diagnosis by the presence of an adult worm identified as Dirofilaria repens. Surgical excision was curative.

This paper deals with a new version of multi-beam particle-image velocimetry. Double-exposure holograms of several light sheets are recorded simultaneously within the volume of a photorefractive BSO crystal. A coherence coding approach and an orthogonal geometry are used to separate holograms from each other. In the reconstruction step, different holograms are read out sequentially starting from the exit face of the crystal. The phase shift introduced by the axial displacement is determined from the analysis of interference fringes. In particular, a procedure which consists of two successive fast Fourier transformation algorithms is applied. En velocimetrie par imagerie de particules, on eclaire le milieu etudie par plusieurs nappes de lumiere contigues pour obtenir les vecteurs vitesse dans differents plans. En procedant par codage de coherence et en mettant a profit le caractere volumique des materiaux photorefractifs tels que les cristaux de BSO, on enregistre simultanement plusieurs hologrammes double exposition, spatialement juxtaposes. Chacun d'entre eux correspond a une nappe donnee. L'avantage principal des cristaux photorefractifs est que, contrairement aux hologrammes de faible epaisseur, les ondes de reference ne se superposent pas. Le nombre de nappes enregistrables simultanement est plus important. La restitution se fait sequentiellement en appliquant la methode d'interrogation par zone. On analyse les franges d'Young formees a partir des paires d'images restituees. Le dephasage introduit par le deplacement axial est calcule avec une procedure comportant deux algorithmes de transformee de Fourier rapide. Ainsi, on determine non seulement les composantes transversales, mais aussi la composante axiale de la vitesse.

Excess molar volume, deviation in viscosity, and deviation in isentropic compressibility for the binary mixtures of amines with N-methylacetamide have been calculated from density, viscosity and speed of sound measurements at T = 308.15 K. The amines chosen for the study are diethyl amine, n-propyl amine, diisopropyl amine, n-butyl amine and di-n-butyl amine. All the properties have been fitted to the Redlich–Kister polynomial using multiparametric non-linear regression analysis to estimate the binary coefficients and standard errors. The results of excess properties have been discussed in terms of molecular interactions.

Dirofilariasis is a zoonosis affecting dogs and cats. It was transmitted to man by mosquito bites. Human dirofilariasis is rare. We report a case of 4-year-old girl presented with a subcutaneous palmar nodule of the hand. Surgical excision shows a nodule encircling the forth flexor tendon. The histological examination established the diagnosis by the presence of an adult worm identified as Dirofilaria repens. Surgical excision was curative.

To study the lymphoid clonality on Tunisian B-cell lymphomas cases by polymerase chain reaction (PCR)-based techniques using DNA from paraffin-embedded tissues.Here we conducted a retrospective PCR clonality study on 73 cases of B-cell lymphomas and 12 reactive lymphoid tissues. The quality of DNA extracted was tested by beta-globin PCR. Consensus primers directed at the FRIII-VH and FRII-VH regions of the immunoglobulin heavy chain (IgH) gene were used to detect clonality.The results showed that 52 of 73 (71%) B-cell lymphomas exhibited good quality of amplifiable DNA. Clonality was found in 77% of cases using the set of primers FRIIIa/LJH/VLJH and in 65.5% using the set of primers FRIIa/LJH/VLJH. Lymphomas derived from pregerminal centre showed a high rate detection of clonal IgH gene rearrangement (100%) compared to other group of tumors derived from germinal centre or postgerminal centre (74.5%). None of the polyclonal controls gave a clonal pattern.This is the first large series of PCR clonality study of IgH gene rearrangements on B-cell lymphoma from Tunisia. Our results were similar to other reports in terms of sensitivity and specificity of these techniques and confirm the interest of that PCR for detecting clonal IgH gene rearrangements in lymphoma.

By replacing an AC-corona-stressed insulator surface by a metal electrode subjected to superposed AC and DC corona, the authors studied the processes responsible for the DC charging of insulators. A main result is that the charging is critically dependent on corona processes at the high-field electrode. A corona electrode that gives positive streamers will give substantially less net charge than an electrode burning in the positive glow (Hermstein corona) mode. However, the streamers may do other damage to insulator surfaces. The balance between the synchronous and impulse current components is found to be the decisive factor in determining the charging of corona-exposed dielectric surfaces. >

In this paper, we report a density functional study of the structural, electronic and pressure-induced solid–solid phase transitions of SrTiO3. These first-principles calculations have been performed using the full potential linearized augmented plane wave method (FP-LAPW) within the generalized gradient approximation (GGA) developed by Perdew–Burke–Ernzerhor for solids (PBEsol). The calculated structural parameters like the lattice parameters, the bulk modulus B and their pressure derivative B ′ are used to analyze the relative stability and phase transitions under pressure of SrTiO3. Calculations were done for the cubic (Pm-3m), tetragonal (I4/mcm, P4/mbm, P4mm) and orthorhombic (Cmcm, Pnma) structures where we found that the tetragonal I4/mcm phase is the most stable structure compared to the other structures at T = 0 K and P = 0 GPa. For the electronic properties calculations, the exchange and correlation effects were treated by the Tran–Blaha modified Becke–Johnson (TB-mBJ) potential to prevent the shortcoming of the underestimation of the energy gaps in both LDA and GGA approximations. The obtained results are compared to available experimental data and to other theoretical calculations.

To study the clinical pattern of coeliac disease in children living in the northwest coast of Libya, to investigate the sensitivity and specificity of D-Xylose, fat load test and antigliadin antibody and their correlation to each other and changes in jejunal biopsy.A 4 year prospective study began in 1993. It includes all suspected coeliacs referred to our department for further evaluation. All have suction jejunal biopsy using Crosby capsule performed for diagnosis, screened at the same time with one hour D-Xylose, 3-5 hours urinary D-Xylose, fat load test and antigliadin antibody and followed up for 2-4 years.The mean age at presentation was 8 years. There was no significant correlation between D-Xylose, fat load test and antigliadin antibody. Antigliadin antibody has 87.5% sensitivity and 50% specificity in this study. Three hours urinary D-Xylose has 93% sensitivity where as one hour D-Xylose has 82% sensitivity and only 25% specificity, whereas fat load test has 69% sensitivity.Blood and urinary D-Xylose and fat load tests are not useful for diagnosing coeliac disease. They have no correlation to each other or to jejunal histology. Antigliadin antibody is superior to the above tests.