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Achieving better speech recognition accuracy under real-time conditions is still a challenging task, and many researchers are striving to improve accuracy. In this paper, we developed a system for recognizing continuous Kannada speech sentences under real-time conditions. To develop the automatic speech recognition (ASR) models, we used task-specific continuous Kannada speech data gathered from speakers/farmers in real-time conditions. We designed an interactive voice response system (IVRS) and collected 40 continuous Kannada speech sentences. We transcribed, validated, and extracted speech features using the Mel frequency cepstral coefficient (MFCC) technique. We used 90% and 10% of validated continuous Kannada speech data for Kaldi system training and decoding, respectively, at different phoneme levels. The experimental results revealed that the time delay neural networks (TDNN) based ASR models outperformed ASR models of other acoustic modelling techniques and the earlier developed deep neural networks (DNN)-hidden Markov model (HMM) based continuous Kannada ASR (CKASR) system. The least word error rate (WER) ASR models are used in developing the real-time end-to-end (E2E) CKASR system. We verified the developed E2ECKASR system by testing it with 550 speakers/farmers under real-time conditions. [ABSTRACT FROM AUTHOR]

At present, many experimental fast reactors have adopted alloy nuclear fuels, for example, U-Zr alloy fuels. During the neutron irradiation process, vacancies and hydrogen (H) impurity atoms can both exist in U-Zr alloy fuels. Here, first-principles density functional theory (DFT) is employed to study the behaviors of vacancies and H atoms in disordered-γ(U,Zr) as well as their impacts on the electronic structure and mechanical properties. The formation energy of vacancies and hydrogen solution energy are calculated. The effect of vacancies on the migration barrier of hydrogen atoms is revealed. The effect of vacancies and hydrogen atom on densities of states and elastic constants are also presented. The results illustrate that U vacancy is easier to be formed than Zr vacancy. The H interstitial prefers the tetrahedral site. Besides, U vacancy shows H-trap ability and can raise the H migration barrier. Almost all the defects lead to decreases in electrical conductivity and bulk modulus. It is also found that the main effect of defects is on the U-5f orbitals. This work provides a theoretical understanding of the effect of defects on the electronic and mechanical properties of U-Zr alloys, which is an essential step toward tailoring their performance. [ABSTRACT FROM AUTHOR]

This article demonstrates the implementation of recurrent neural network (RNN) model in optimizing amplitude versus offset (AVO) attributes for indicating lithology and hydrocarbon zone on seismic data. Several drawbacks exist in the conventional implementation of AVO attributes for hydrocarbon exploration, including ambiguous AVO amplitude response as direct hydrocarbon indicators (DHIs), high cost of conventional seismic inversion and ambiguity from a non-absolute range of AVO scale of quality factor of P-wave (AVO SQp) and AVO scale of quality factor of S-wave (AVO SQs) attributes. Hence, this study aimed to optimize the application of AVO attributes by implementing an RNN model that solves nonlinear approximation with a faster, more economical, and reliable approach, supplied with well data as the data control. Sixteen features were extracted from seismic data as input with two targets of SQp and SQs from wells as output in the Angsi field. The model consisted of the improved algorithm of standard RNN called gated recurrent unit layers, followed by a simple RNN layer, and fully connected dense layers to predict SQp and SQs as lithology and hydrocarbon indicators, respectively. The model managed to predict the I-35 hydrocarbon reservoir zone anomalies, characterized by low SQp (sand-prone interval) and high SQs (hydrocarbon-bearing interval). The results indicated that the proposed RNN model performed efficiently as an alternative approach to bypass the conventional seismic inversion method and to optimize the application of AVO attributes in indicating lithology and hydrocarbon zone in seismic data. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the contribution of the mixing enthalpy to the stability of the faced-centered cubic (fcc) phase of the Co–Cr–Fe–Mn–Ni system. For this purpose, systematic first principles calculations on Special Quasirandom Structures (SQS) were performed in a comprehensive manner on the fcc solution in every 5 2 = 10 binary, 5 3 = 10 ternary, 5 4 = 5 quaternary and the quinary systems. The magnetic contributions have been considered carefully i.e. including non-collinear spin polarization. An analysis of the different system order interactions to the enthalpy of mixing is detailed. This concludes that, at equiatomic composition, there is no special "cocktail" effect with an increase of components and that the thermodynamic properties can be well anticipated from the lower order systems, essentially binary and ternary systems. [ABSTRACT FROM AUTHOR]

KY02111 is a widely used small molecule that boosts cardiomyogenesis of the mesoderm cells derived from pluripotent stem cells, yet its molecular mechanism of action remains elusive. The present study resolves the initially perplexing effects of KY02111 on Wnt signaling and subsequently identifies squalene synthase (SQS) as a molecular target of KY02111 and its optimized version, KY‐I. By disrupting the interaction of SQS with cardiac ER‐membrane protein TMEM43, KY02111 impairs TGFβ signaling, but not Wnt signaling, and thereby recapitulates the clinical mutation of TMEM43 that causes arrhythmogenic right ventricular cardiomyopathy (ARVC), an inherited heart disease that involves a substitution of myocardium with fatty tissue. These findings reveal a heretofore undescribed role of SQS in TGFβ signaling and cardiomyogenesis. KY02111 may find its use in ARVC modeling as well as serve as a chemical tool for studying TGFβ/SMAD signaling. [ABSTRACT FROM AUTHOR]

At present, many experimental fast reactors have adopted alloy nuclear fuels, for example, U-Zr alloy fuels. During the neutron irradiation process, vacancies and hydrogen (H) impurity atoms can both exist in U-Zr alloy fuels. Here, first-principles density functional theory (DFT) is employed to study the behaviors of vacancies and H atoms in disordered-γ(U,Zr) as well as their impacts on the electronic structure and mechanical properties. The formation energy of vacancies and hydrogen solution energy are calculated. The effect of vacancies on the migration barrier of hydrogen atoms is revealed. The effect of vacancies and hydrogen atom on densities of states and elastic constants are also presented. The results illustrate that U vacancy is easier to be formed than Zr vacancy. The H interstitial prefers the tetrahedral site. Besides, U vacancy shows H-trap ability and can raise the H migration barrier. Almost all the defects lead to decreases in electrical conductivity and bulk modulus. It is also found that the main effect of defects is on the U-5f orbitals. This work provides a theoretical understanding of the effect of defects on the electronic and mechanical properties of U-Zr alloys, which is an essential step toward tailoring their performance.

The use of predictive models to examine defect production and migration in metallic systems requires a thorough understanding of the energetics of defect formation and migration. In fully miscible alloys, atomistic properties will all have a range of values that are heavily dependent on local atomic configurations. In this work we have used the atomistic simulation tool Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) to investigate the impact of first nearest neighbor configuration on vacancy formation energies at 0 K in γ-U-Zr alloys of varying Zr concentrations. The properties of randomly generated alloy microstructures were also compared with those produced as special quasi-random structures (SQS) using the “mcsqs” code within the Alloy Theoretic Automated Toolkit. Results have confirmed that local configuration can have a significant impact on measured properties and must be considered when characterizing miscible alloy systems. Results also indicated that the generation method of the random structure (i.e., via random species assignment or a method of enforced randomness) does not result in a measurable difference in average vacancy formation energies in miscible U-Zr systems.

First-principles calculations have increasingly become an essential tool for providing additional thermodynamic data for assessing thermodynamic databases using the CALPHAD methodology. As computational power increases and becomes easily accessible, first-principles calculation results have become more presented along with the experimental procedures to determine the thermochemical properties of the phases within a target system. This can help accelerate the alloy development process, even in complex multi-component systems. By using only first-principles calculation data for the both thermodynamic description and interaction parameters of end-members, an Al–Ni–Ti ternary thermodynamic database is constructed. By relying on the existing materials database for ground state stability of the known compounds, the constructed Al–Ni–Ti thermodynamic database can mostly capture all the features related to the solid-state phases appear in the ternary phase diagram comparable to that of the published database from an experimental data assessment. • Thermodynamic database from first-principles for solid phases. • Special quasi-random structures are used for representing solid-solution disordered phases. • Finite temperature thermodynamic properties include lattice vibrations and thermal electronic excitation contributions. • Part of an Al–Ni–X multinary system. [ABSTRACT FROM AUTHOR]

Dehydrosqualene synthase (CrtM), as a squalene synthase-like enzyme from Staphylococcus aureus , can naturally utilize farnesyl diphosphate to produce dehydrosqualene (C 30 H 48 ). However, no study has documented the natural production of squalene (C 30 H 50 ) by CrtM. Here, based on an HPLC-Q-Orbitrap-MS/MS study, we report that the expression of crtM in vitro or in Bacillus subtilis 168 both results in the output of squalene, dehydrosqualene, and phytoene (C 40 H 64 ). Notably, wild-type CrtM exhibits a significantly higher squalene yield compared to squalene synthase (SQS) from Bacillus megaterium with an approximately 2.4-fold increase. Moreover, the examination of presqualene diphosphate's stereostructures in both CrtM and SQS enzymes provides further understanding into the presence of multiple identified terpenoids. In summary, this study not only provides insights into the promiscuity demonstrated by squalene synthase-like enzymes but also highlights a new strategy of utilizing CrtM as a potential replacement for SQS in cell factories, thereby enhancing squalene production.

Featured Application: This article demonstrates SQp and SQs methods as the new AVO attributes that sensitive to determine facies and fluid analysis. Amplitude versus offset (AVO) analysis integration to well log analysis is considered one of the advanced techniques to improve the understanding of facies and fluid analysis. Generating AVO attributes are one solution to give an accurate result in facies and fluid characterization. This study is focused on a field of Northern Malay basin, which is associated with a fluvial-deltaic environment, where this system has high heterogeneity, whether it is vertically or horizontally. This research is aimed to demonstrate an application of the scale of quality factor of P-wave (SQp) and the scale of quality factor of S-wave (SQs) AVO attributes for facies and fluid types separation in field scale. These methods are supposed to be more sensitive to predict the hydrocarbons and give less ambiguity. SQp and SQs are the new AVO attributes, which derived from AVO analysis and created according to the intercept product (A) and gradient (B). These new attributes have also been compared to the common method, which is the Scaled Poisson's Ratio attribute. By comparing with the Scaled Poisson's Ratio attribute, SQp and SQs attributes are more accurate in determining facies and hydrocarbon. SQp and SQs AVO attributes are integrated with well log data and considered as the best technique to determine facies and fluid distribution. They are interpreted by using angle-stack seismic data based on amplitude contrast on interfaces. Well log data, e.g., density and sonic logs, are used to generate synthetic seismogram and well tie requirements. The volume of shale, volume of coal, porosity, and water saturation logs are used to identify facies and fluid in well log scale. This analysis includes AVO gradient analysis and AVO cross plot to identify the fluid class. Gassmann's fluid substitution modeling is also generated in the well logs and AVO synthetics for in situ, pure brine, and pure gas cases. The application of the SQp and SQs attributes successfully interpreted facies and fluids distributions in the Northern Malay Basin. [ABSTRACT FROM AUTHOR]

The phase diagram and thermodynamic data of the H–Nb system are evaluated and re-assessed to improve the description of this system. This system is modeled up to a few MPa. Only the gas phase and the solid phases are considered in the present study. Since only a few data were available for the H–Nb–Zr ternary system, a new set of experimental data has been obtained in the present work. For the first time, the solubility of niobium into the ε-ZrH 2 phase is found. In addition, Density Functional Theory calculations and the Special Quasirandom Structures method are used to determine the formation enthalpies of all the compounds and the mixing enthalpies in the different phases, respectively. Finally, the literature data as well as our experimental and calculated data are used for the Calphad modeling of the H–Nb–Zr system. [ABSTRACT FROM AUTHOR]

Objective: To study the influence of over-expression of three functional genes involved in GC biosynthetic pathway, GuHMGR, GuSQS1, and GuBAS on GC production. Methods: Three plant expression vectors were constructed and transformed into Agrobacterium tumefaciens EHA105, which were used to infect Glycyrrhiza uralensis hypocotyls explants. After induction, selection, differentiation, culture, and transplantation, 12, 15, and 5 regenerated plants over-expressing GuHMGR, GuSQS1, and GuBAS, were obtained, respectively. Results: RT-PCR analysis showed these transgenic regenerated G. uralensis plants had 2–6 copies of GuHMGR, GuSQS1, or GuBAS. HPLC analysis showed the contents of 18α- and 18β-GC in all transgenic regenerated samples were both higher than that in the blank control. With the increase of copy numbers of GuHMGR, GuSQS1, and GuBAS, the contents of 18α- and 18β-GC were both increased in most samples. The highest 18α- and 18β-GC contents in transgenic regenerated plants were about 3.05 times and 2.80 times higher than that in the blank control, respectively. Conclusion: Over-expression of the GuHMGR, GuSQS1, and GuBAS genes enhance the accumulation of 18α- and 18β-GC in the roots and rhizomes of G. uralensis. We hope this work can lay a foundation for the molecular breeding research of G. uralensis and improving the quality of the roots and rhizomes of G. uralensis cultivars.

Abstract This work reports the Calphad modelling of the Cr–Nb–Sn–Zr quaternary system. In a previous paper, the thermodynamic modelling of the Cr–Nb–Sn system was presented. Since no experimental data were available for the Cr–Sn–Zr ternary system, new experimental data are provided, within this study, on the isothermal section at 900 °C. A ternary C 14 phase has been identified on the Sn-poor side of the phase diagram. In addition to these experimental data, Density Functional Theory (DFT) calculations are carried out in order to determine formation enthalpies of the stable and metastable compounds. At last, the Special Quasirandom Structures (SQS) method is jointly used with DFT calculations in order to estimate the mixing enthalpies of the A 2 and A 3 binary solid solutions. Finally, these experimental and calculated data in addition to those from the literature, are used as input data for the Calphad modelling of the Cr–Zr, Nb–Zr and Sn–Zr binary systems and the Cr–Nb–Zr, Cr–Sn–Zr and Nb–Sn–Zr ternary systems. A complete database for the Cr–Nb–Sn–Zr quaternary system is provided. [ABSTRACT FROM AUTHOR]

Amplitude versus offset (AVO) analysis integration to well log analysis is considered one of the advanced techniques to improve the understanding of facies and fluid analysis. Generating AVO attributes are one solution to give an accurate result in facies and fluid characterization. This study is focused on a field of Northern Malay basin, which is associated with a fluvial-deltaic environment, where this system has high heterogeneity, whether it is vertically or horizontally. This research is aimed to demonstrate an application of the scale of quality factor of P-wave (SQp) and the scale of quality factor of S-wave (SQs) AVO attributes for facies and fluid types separation in field scale. These methods are supposed to be more sensitive to predict the hydrocarbons and give less ambiguity. SQp and SQs are the new AVO attributes, which derived from AVO analysis and created according to the intercept product (A) and gradient (B). These new attributes have also been compared to the common method, which is the Scaled Poisson’s Ratio attribute. By comparing with the Scaled Poisson’s Ratio attribute, SQp and SQs attributes are more accurate in determining facies and hydrocarbon. SQp and SQs AVO attributes are integrated with well log data and considered as the best technique to determine facies and fluid distribution. They are interpreted by using angle-stack seismic data based on amplitude contrast on interfaces. Well log data, e.g., density and sonic logs, are used to generate synthetic seismogram and well tie requirements. The volume of shale, volume of coal, porosity, and water saturation logs are used to identify facies and fluid in well log scale. This analysis includes AVO gradient analysis and AVO cross plot to identify the fluid class. Gassmann’s fluid substitution modeling is also generated in the well logs and AVO synthetics for in situ, pure brine, and pure gas cases. The application of the SQp and SQs attributes successfully interpreted facies and fluids distributions in the Northern Malay Basin.

The release of new olive cultivars with an increased squalene content in their virgin olive oil is considered an important target in olive breeding programs. In this work, the variability of the squalene content in a core collection of 36 olive cultivars was first studied, revealing two olive cultivars, 'Dokkar' and 'Klon-14', with extremely low and high squalene contents in their oils, respectively. Next, four cDNA sequences encoding squalene synthases (SQS) were cloned from olive. Sequence analysis and functional expression in bacteria confirmed that they encode squalene synthases. Transcriptional analysis in distinct olive tissues and cultivars indicated that expression levels of these four SQS genes are spatially and temporally regulated in a cultivar-dependent manner and pointed to OeSQS2 as the gene mainly involved in squalene biosynthesis in olive mesocarp and, therefore, in the olive oil. In addition, the biosynthesis of squalene appears to be transcriptionally regulated in water-stressed olive mesocarp.

Thermodynamic stability of the MoNi 2 and MoNi 8 compounds has been discussed in detail, and decision about their inclusion in thermodynamic assessment of the Mo–Ni system has been made. Enthalpies of formation of all Mo–Ni intermetallic compounds have been determined with the help of DFT calculations whereas enthalpies of mixing in the solid solutions are estimated using special quasi-random structures. Experimental phase equilibria information gathered in our recent partial investigation of the Mo–Ni system has been incorporated and thermodynamic reassessment of the Mo–Ni system has been performed with the help of the CALPHAD method. The calculated Mo–Ni phase diagram showed good agreement with selected experimental information. [ABSTRACT FROM AUTHOR]

Nickel-based alloys are extensively utilized in high-temperature applications where corrosion resistance and mechanical strength are important. The formation of an oxide-layer on these surfaces is associated with corrosion resistance but the early stages of this process are not well understood and difficult to model. The studies in the available literature are currently limited to introducing an element such as Cr to the top layer of the nickel surface slab. While this approach has yielded some useful insights, it is not entirely accurate. In this work, we used the special quasi-random structure (SQS) method to first build reliable representations of the Ni-Cr alloy. Next, several surface slabs were cut from these alloys and oxygen adsorption at 0.25 ML coverage was investigated. It was generally observed that Cr made the oxygen adsorption process more thermodynamically favorable and the nature of the interaction was partially electrostatic. We then introduced Mo substitutions to the top layer of the surface to investigate the effect of low levels of Mo on the oxygen adsorption. It was revealed that Mo helped further stabilize the adsorbed configuration. A correlation was observed between the net charge transferred and the thermodynamic stability of the metal-oxygen system and the stability of the adsorbate on the alloy surface was mainly dependent on the local environment of the adsorbate. The subsurface atoms for the cases considered in this study provided only minor contribution to the stability of the alloy-oxygen system and hence utilizing the doping approach on the top layer may be appropriate for studying oxygen adsorption on this particular alloy surface to a good approximation but this issue requires further investigation. Finally, the workfunctions of the surfaces and the effects of oxygen adsorption on the workfunctions were also characterized and the implications of the results for corrosion resistance were discussed. [ABSTRACT FROM AUTHOR]

The Cr-Nb-Sn system has been studied experimentally, by first principles calculation and finally modeled with the Calphad method. The experimental study has been carried out on the Cr-Sn binary system to determine the solubility of Sn in the A 2 (Cr) solid solution, but also in the Cr-Nb-Sn ternary system in order to determine phase equilibria of the isothermal section at 800 °C and 1100 °C. Besides, the formation enthalpies of all the ordered configurations of the C 15 and A 15 phases and the stoichiometric Nb 6 Sn 5 and NbSn 2 phases have been calculated using the Density Functional Theory (DFT). The mixing enthalpies of the A 2 binary solid solutions have been estimated using the Special Quasirandom Structures (SQS). All these new experimental and calculated data have been taken into account for a new thermodynamic assessment of the three binary and the ternary systems. [ABSTRACT FROM AUTHOR]

First-principles electronic structure calculations have been performed for defect structures in nonstoichiometric B2 AlCo and GaCo. To determine the type of constitutional defects, the compositional dependence of the energy of formation and lattice parameter was obtained by calculations employing supercells of various sizes (16 and 32 atoms) as well as special quasirandom structures (SQSs) developed for random pseudobinary ABC with compositions x = 0.25 and 0.5. According to the results, Co vacancies are the constitutional point defects in the Al-rich side of both B2 AlCo and B2 GaCo, while Co vacancies present the minimum energy for the Ga-rich side. For the Co-rich side of both B2 AlCo and B2 GaCo, the Co antisite is the most stable defect. To investigate the thermal defect concentrations at finite temperature, we adopted the Wagner-Schottky model using enthalpies of formation of point defects obtained from the SQS approach. The present results suggest that the predominant thermal defects in AlCo are of complex type whereas for GaCo they are of interbranche Co type. The results of these calculations show agreement with available theoretical and experimental data. [ABSTRACT FROM AUTHOR]

Palladium, rhodium and ruthenium are abundant fission products that form in oxide fuels in nuclear reactors. Under operating conditions, these Platinum-Group Metal (PGM) fission products accumulate in high concentration at the rim of the oxide fuel and mainly precipitate into metallic solid solutions. Their thermochemistry is of significant interest to predict the high temperature chemical interactions between the fuel and the cladding or the possible precipitation of PGM phases in high level nuclear waste glasses. To predict the thermodynamic properties of these PGM fission products, a thermodynamic modeling is being developed on the ternary Pd Rh Ru system using the Calphad method. Because experimental thermodynamic data are scarce, Special Quasirandom Structures coupled with Density Functional Theory methods were used to calculate mixing enthalpy data in the solid solutions. The resulting thermodynamic description based on only binary interaction parameters is in good agreement with the few data on the ternary system. [ABSTRACT FROM AUTHOR]

Point defect structure of B2 TrSc (TrCd, Ru) alloys was investigated using supercell and special quasi-random structure (SQS) approaches. According to our results, Tr and Sc anti-sites are the constitutional point defects in Tr-rich and Sc-rich B2 TrSc, respectively. To investigate the thermal defect concentrations at finite temperatures, we adopted the Wagner-Schottky model using point defect formation enthalpies obtained from supercell and SQS approaches. The present results suggest that the predominant thermal defects in B2 CdSc are of exchange type, and in B2 RuSc are of interbranch Sc type. The calculated results show an agreement with the available theoretical and experimental data. [ABSTRACT FROM AUTHOR]

Abstract: The phase equilibria and thermodynamic properties of the Mo–Re system are studied by combining first-principle and CALPHAD approach. The mixing enthalpies in the bcc and hcp solution phases are estimated by first-principle calculations using the special quasirandom structures. The liquid, bcc and hcp phases are described by a substitutional solution model. The intermetallic phases, σ and χ, are described with the compound energy formalism with, respectively, 5 and 4 sublattices (SL) using the formation enthalpies of all the end-members directly from ab initio calculations. A phase diagram in agreement with the available experimental knowledge is obtained thanks to a least square procedure involving a limited number of parameters. Introducing all the elements in all the sublattices of the structure allows a proper description of the configuration of the intermetallic phases. Different simplifications of the description of the σ phase are considered. The ideal 4SL simplification is equivalent to the full description. The 3SL and 2SL models require excess parameters in order to fit reasonably the experimental phase diagram. Among these, only the (Mo,Re)10(Mo,Re)12(Mo,Re)8 model allows to closely approximate the low temperature thermodynamic properties of the full description. [Copyright &y& Elsevier]

Background Sebaceous carcinoma represents a rare and potentially fatal adnexal malignancy. Poorly-differentiated sebaceous carcinoma consisting of infiltrative basaloid tumor cells with inapparent lipid vesicles can mimic basal cell carcinoma (BCC). Conversely, other epithelial tumors can exhibit clear cell histopathology and mimic sebaceous carcinoma. At the present time, immunohistochemical markers unique for sebaceous carcinoma are limited. Methods We evaluated the expression of three lipid synthesis/processing protein markers alpha/beta hydrolase domain-containing protein 5 ( ABHD5), progesterone receptor membrane component-1 ( PGRMC1) and squalene synthase (SQS) in sebaceous carcinoma and investigated their utility in differentiating sebaceous tumors from BCC with clear cell features. Immunohistochemistry was performed on 23 sebaceous carcinomas, 14 sebaceomas and 14 BCCs with clear cell features. Results In sebaceous carcinomas, ABHD5 showed dispersed, cytoplasmic punctate and/or vesicular staining (n = 19/23, 83%), while PGRMC1 and SQS each showed vesicular and membranous staining in tumor cells (n = 22/23, 96%). In all sebaceomas, these markers highlighted tightly clustered lipid vesicles in sebocytes. All BCCs with clear cell features were negative for these three markers. Conclusion ABHD5, PGRMC1 and SQS are novel markers for sebaceous carcinoma and can reliably distinguish sebaceous neoplasms from non-sebaceous tumors, specifically BCC with clear cell features. [ABSTRACT FROM AUTHOR]

For the potential new permanent magnet materials, SmFe 12 -based compounds, Ti plays an important role in stabilizing the SmFe 12 -based structures. Thermodynamic properties of the systems relating to Sm–Fe–Ti ternary system become indispensable for the future development of the SmFe 12 -based magnets. In order to construct the multi-component thermodynamic database for SmFe 12 -based compounds, the thermodynamic properties and phase diagram of Sm–Ti binary system is necessary. In this work, we attempted to construct the Sm–Ti binary thermodynamic database using data obtained mainly from first-principles. First-principles calculations are performed to obtain the Gibbs energy of ordered and disordered structures within the binary system and used for parameterized the Gibbs energy descriptions of various phases in the Sm–Ti binary system through the CALPHAD methodology, the first Sm–Ti phase diagram has been calculated accordingly. • Thermodynamic database from first-principle for solid phases and experiment for liquid phase. • Special quasi-random structures are used for representing solid-solution disordered phases. • Finite temperature thermodynamic properties are including lattice vibrations and thermal electronic excitation contributions. • Part of Sm–Fe–Ti–X multinary system for SmFe 12 permanent magnet. [ABSTRACT FROM AUTHOR]

We extend the small set of ordered structures (SSOS) method to calculate several typical materials properties of high entropy alloys (HEAs) with short range order (SRO). Using both equimolar and non-equimolar quinary CoCuFeNiPd HEAs with SRO as an example, we calculate ground state energy, lattice constant, mass density and elastic moduli, and compare them with those obtained from the special quasi-random structure (SQS) method. The calculated properties are in good agreement with those obtained by SQS. Importantly, the computational cost of the SSOS method for achieving the same accuracy is only a small fraction of the computational cost of the SQS method. We further show that the application of machine learning methods can further reduce the computational cost of the SSOS method and maintain the same level of accuracy, making it especially suitable for high-throughput calculations of HEAs with SRO. • The set of small ordered structures method is extended to treat both equimolar and non-equimolar HEAs with SRO. • The SSOS shows a high accuracy and is validated by the SQS method. • The SSOS method shows a much higher computational efficiency than the SQS method. [ABSTRACT FROM AUTHOR]

Abstract: The Steiner quadruple systems of order 16 are classified up to isomorphism by means of an exhaustive computer search. The number of isomorphism classes of such designs is . Properties of the designs—including the orders of the automorphism groups and the structures of the derived Steiner triple systems of order 15—are tabulated. A consistency check based on double counting is carried out to gain confidence in the correctness of the classification. [Copyright &y& Elsevier]

Abstract: A previous thermodynamic model for the Mg–Zr system has been modified by using new information derived from first-principles calculations in combination with existing experimental data on phase boundaries, invariant reactions as well as limited thermochemical measurements in the liquid phase. Special quasirandom structures for the hcp and bcc structures are used to simulate random solid solutions at 25, 50 and 75 at.%. The total energies of these structures are calculated through first-principles methods and the enthalpies of mixing are used in combination with the available experimental information as input data in the thermodynamic modelling . In addition to experiments and first-principles calculations, stability conditions are also used to prevent unrealistic metastable and higher-order extrapolations. In general, the calculated phase diagram is found to agree well with experiments. The present model is also compared to previous thermodynamic descriptions and it is shown that some of the inconsistencies of the previous model can be resolved by the combined first-principles/CALPHAD approach. [Copyright &y& Elsevier]

Materials properties of uranium oxycarbide (UCO), a fuel candidate for high temperature gas reactors (HTGRs), are investigated using the Hubbard corrected density functional theory (DFT+ U) and ab initio molecular dynamics (AIMD+ U). To accurately describe UCO systems within the supercell approach, we have evaluated the structural disorder of the ion sublattice within the special quasirandom structures (SQS) approach. The ground-state of UC x O 2-x and UC 1-x O x systems was found by examination of the electronic configuration, the occupation matrix and the Hubbard U parameter. We obtained the electronic properties, lattice structure, formation enthalpy and free energy of mixing of the stoichiometric UC x O 2-x and UC 1-x O x phases. Subsequently, we have determined the preferential phase of UCO (UC x O 2-x or UC 1-x O x) for low carbon and oxygen concentrations, respectively. In particular, UC x O 2-x was found stable for carbon content lower than 50%, with carbon atoms in the first coordination shell out of the perfect fluorite positions, driven by the formation of C 2 groups as in α -UC 2. Moreover, the analysis of the radial distribution functions shows that structures with C 2 groups remain stable in the range of temperatures from 300 to ∼ 2500 K. [ABSTRACT FROM AUTHOR]

• Methyl-jasmonate elicitor was applied to field-grown plants of Withania somnifera. • Elicitor-treated (20 μM for 4 h) plants produced maximum withanolides. • Treated plants showed up-regulated expression of key withanolide biosynthesis genes. • Withanolides showed significant cytotoxicity against human breast cancer cell line. • A simple and fast analytical method was developed for separation of withanolides. Withania somnifera (L.) Dunal, is an important medicinal plant with tremendous use in the herbal drug industry. Withanolides are the major bioactive metabolites present in the leaves of W. somnifera. However, due to the low abundance of withanolides, it is difficult to fulfil the market demand. The rationale of this study was to develop a simple technology for enhanced withanolide biosynthesis in field-grown plants of W. somnifera. Exogenous elicitor-treatment to the field-grown plants is an effective strategy to increase the production of many plant secondary metabolites. In this study, a high-performance liquid chromatography method was developed for the rapid separation of withanolides from the leaves along with phenolic acid and flavonoids. Field-grown plants of W. somnifera were directly used for methyl jasmonate elicitor treatment using a novel closed polybag approach. In this approach, branches were covered with a polybag and then MeJa was injected using a specially designed vial. Methyl-jasmonate (20μM) treatment for 4 h resulted in 2.2-fold, 1.9-fold, 2.0-fold, and 2.2-fold increase in withaferin A, withanolide A, withanolide D, and withanone production, respectively, over the control treatment. Methyl-jasmonate -treatment increased the transcript levels of four key withanolide biosynthetic genes, namely 3-hydroxy-3-methylglutaryl coenzyme A reductase , squalene synthase , squalene epoxidase , and cycloartenol synthase. Methyl-jasmonate -treated leaf extracts and isolated pure withanolides also showed a significant cytotoxic effect against selected human breast cancer cell line. These results suggest that MeJa-treatment using a closed polybag system is an effective and easy-to-perform elicitation strategy for the enhanced production of bioactive withanolides using field-grown plants of W. somnifera. Farmers and industry can easily adapt this technology to meet the growing demand for bioactive withanolides. [ABSTRACT FROM AUTHOR]

This paper is dedicated to the Calphad modelling of the Cr–Fe–Nb–Sn–Zr quinary system. In previous papers, the thermodynamic modelling of the Cr–Nb–Sn–Zr quaternary system, the Fe–Sn–Zr and Fe–Nb–Zr ternary systems as well as the Fe–Nb binary system were carried out. Since no experimental data were available for the Cr–Fe–Sn and Fe–Nb–Sn ternary systems, new partial isothermal sections have been measured at 1073K and 973K, respectively. In addition to these experimental data, Density Functional Theory (DFT) calculations are performed in order to determine formation enthalpies of the stable and metastable ordered compounds. At last, the Special Quasirandom Structures (SQS) method is used together with DFT calculations in order to calculate the mixing enthalpy of the A 2 (bcc) binary solid solution. Finally, these experimental and calculated data are jointly used with those from the literature as input data for the Calphad modelling of the Cr–Fe binary system as well as the Cr–Fe–Nb, Cr–Fe–Sn, Cr–Fe–Zr and Fe–Nb–Sn ternary systems. The ternary systems are then combined into a quinary database for which application examples are provided. [ABSTRACT FROM AUTHOR]

We present an ab-initio -based effective interaction model (EIM) for the study of magnetism, thermodynamics, and their interplay in body-centered cubic Fe-Co alloys, with Co content from 0 to 70%. The model includes explicitly both spin and chemical variables. For the former, a Heisenberg formalism is adopted. But, the spin magnitude of each Fe atom varies according to its local chemical environment, following a simple rule determined by density functional theory (DFT) calculations. The proposed model is able to describe precisely the ground-state magneto-energetic landscape of both chemically ordered and disordered Fe-Co systems, as given by DFT and experiments. In combination with on-lattice Monte Carlo simulations, it enables an accurate prediction at finite temperatures. In particular, the Curie point and the chemical order–disorder (B2-A2) transition temperature are accurately predicted, for all the concentrations considered. A strong dependency of the chemical transition temperature on the magnetic configuration is evidenced and analyzed. We also suggest a more important effect of magnetic rather than vibrational entropy on the chemical transition. However, this transition is not affected by a commonly accessible external magnetic field. [ABSTRACT FROM AUTHOR]

The Fe–Sn–Zr system has been studied by first principles calculation and modelled with the Calphad method using the literature and new experimental data. The work includes a revision of Fe–Sn and Fe–Zr systems. Our experimental study has confirmed that the W 5 Si 3 phase (stoichiometry Zr 5 Sn 2,3 Fe 0,7) is stable at 1350 °C but also down to 1000 °C. Moreover, the crystal structure of the X " phase has been determined. The formation enthalpies of all the ordered configurations of the C 15, C 16, C 36, E 1a phases and the stoichiometric Fe 5 Sn 3 , Fe 3 Sn 2 , FeSn, FeSn 2, Fe 23 Zr 6 , FeSn 2 Zr 6 (θ), Fe 36.36 Sn 36.36 Zr 27.27 (N) et Fe 14.39 Sn 43.47 Zr 39.13 (X ″) compounds have been calculated using the Density Functional Theory (DFT). The mixing enthalpies of the A 1, A 2 and A 3 binary solid solutions have been calculated using the Special Quasirandom Structures (SQS) and DFT calculation. From these new experimental and calculated data, new thermodynamic assessments are proposed for Fe–Sn, Fe–Zr and Fe–Sn–Zr systems. • New experiments are provided for Fe–Sn–Zr system. • The structure of X″ phase has been determined. • a complete Calphad description of Fe–Sn–Zr system is given for the first time. • New thermodynamic assessments are provided for Fe–Sn and Fe–Zr systems. [ABSTRACT FROM AUTHOR]

Among the ferromagnetic binary alloys, body centered cubic (bcc) Fe-Co is the one showing the highest magnetization. It is known experimentally that ordered Fe-Co structures show a larger magnetization than the random solid solutions with the same Co content. In this work, based on density functional theory (DFT) studies, we aim at a quantitative prediction of this feature, and point out the role of the orbital magnetic moments. Then, we introduce a DFT-based analytical model correlating local magnetic moments and chemical compositions for Co concentrations ranging from 0 to 70 at.%. It is also extended to predict the global magnetization of both ordered and disordered structures at given concentration and chemical short range orders. The latter model is particularly useful for interpreting experimental data. Based on these models, we note that the local magnetic moment of a Fe atom is mainly dictated by the Co concentration in its first two neighbor shells. The detailed local arrangement of the Co atoms has a minor effect. These simple models can fully reproduce the difference in magnetization between the ordered and disordered Fe-Co alloys between 30% and 70% Co, in good agreement with experimental data. Finally, we show that a similar model can be established for another bcc binary Fe alloy, the Fe-Ni, also presenting ferromagnetic interactions between atoms. [ABSTRACT FROM AUTHOR]

Gas amplification factors, over the range 1 to ∼105 were measured for the mixtures of Xe/CO2, Xe/CO2/O2 and Xe/CO2/N2 as the function of the applied voltage for straw tubes geometry. Special attention was put to the transition from proportional mode to self-quenching streamer and corona discharge. [Copyright &y& Elsevier]

The first committed steps of steroid/hopanoid pathways involve squalene synthase (SQS). Here, we report the Escherichia coli production of diaponeurosporene and diapolycopene, yellow C30 carotenoid pigments, by expressing human SQS and Staphylococcus aureus dehydrosqualene (C30 carotenoid) desaturase (CrtN). We suggest that the carotenoid pigments are synthesized mainly via the desaturation of squalene rather than the direct synthesis of dehydrosqualene through the non-reductive condensation of prenyl diphosphate precursors, indicating the possible existence of a "squalene route" and a "lycopersene route" for C30 and C40 carotenoids, respectively. Additionally, this finding yields a new method of colorimetric screening for the cellular activity of squalene synthases, which are major targets for cholesterol-lowering drugs., (Copyright © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.)