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Fabricating earth-abundant bifunctional water splitting electrocatalysts with high efficiencies to replace noble metal-based Pt and IrO2 catalysts is in great demand for the development of clean energy conversion technologies. Molybdenum disulfide (MoS2) nanostructures have attracted much attention as promising material for hydrogen evolution reaction (HER). The production of hydrogen gas by help of potential efficient earth abundant metal oxides, and stable electrolysis seems a promising for hydrogen evolution reaction pathway in 1 M potassium hydroxide electrolyte media is a hot research topic in the field for clean energy conversion, renewable energies and storage. Here we propose asystem composed NiO nanostructures and MoS2 deposited on (MoS2@NiO). Here, by hydrothermal method NiO prepared and MoS2@NiO by an electrospinning technique complex, can be used as catalyst to produce a large amount of hydrogen gas bubbles. The NiO nanostructures composite having highest synergistic behavior fully and covered by the MoS2. For the MoS2@NiO nano composite catalyst, experiment applied in 1 M KOH for the production of hydrogen evolution reaction which exhibits distinct properties from the bulk material. Overpotential values recorded low 406 mV and current density 10 mA cm−2 measured. Co-catalysts characterized by using different techniques for deep study as scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Owing to their unique structure, as-prepared nanocomposite exhibited enhanced catalytic performance for HER due to high electroactive surface area and swift electron transfer kinetics. Based on the HER polarization curves at low potential electrochemical to examine the effects of intercalants HER catalytic efficiency. Our findings establish low Tafel slope (44 mV/decade) and the catalyst stable for at least 13 h. This simple exploitation of MoS2@NiO composite catalysts depending on the intended application of their electrochemistry.

Histone H1 acts as an essential chromatin component and participates in the formation of higher chromatin structures together with core histones. In addition, H1 also has important functions in physiological processes such as gene expression regulation, DNA repair, and the immune response. In this study, the histone homologous protein Pm-H1.2-like was identified from the transcriptome database of Pagrus major we studied previously. Conservatism of evolution was investigated by sequence alignment and phylogenetic analysis. Transcripts of Pm-H1.2-like were detected in P. major tissues. The highest expression level was found in gill and skin tissues. Consistent with the data from the transcriptome database, we observed that the expression of Pm-H1.2-like was rapidly induced in nonspecific cytotoxic cells (NCCs) infected with inactivated Vibrio anguillarum. Gene silencing of Pm-H1.2-like by RNAi significantly suppressed the expression of NK-lysin and GZMB in NCCs at 12 h after pathogen stimulation, but had no significant effect on IFN-γ expression. Next, we obtained the fusion proteins rPm-H1.2-like and rPm-H1.2-like (36-80) through prokaryotic expression. ELISA showed that rPm-H1.2-like bound to oligonucleotide (ODN) in a concentration-dependent manner, while no binding activity of rPm-H1.2-like (36-80) with ODN was observed. This study confirmed that Pm-H1.2-like actively participates in the immune response of NCCs to bacterial infection, deepening the understanding of the immune features of histone H1 in fish.

Burkholderia sp. JP2-270, a bacterium with a strong ability to inhibit the growth of Rhizoctonia solani, was isolated from the rhizosphere of rice. The phylogenetic analysis based on 16S rRNA gene revealed that JP2-270 belonged to Burkholderia cepacia complex. Here, we present the complete genome sequence of Burkholderia sp. JP2-270, which consists of three circular chromosomes (Chr1 3,723,585 bp, Chr2 3,274,969 bp, Chr3 1,483,367 bp) and two plasmids (Plas1 15,126 bp, Plas2 428,263 bp). A total of 8193 protein coding genes were predicted in the genome, including 67 tRNA genes, 18 rRNA genes and 4 ncRNA genes. In addition, mutation analysis of Burkholderia sp. JP2-270 revealed that the gene bysR (DM992_17470), encoding a lysR-type transcriptional regulator, was essential for the antagonistic activity of Burkholderia sp. JP2-270 against R. solani GD118 in vitro and in vivo. Identification of regulatory gene associated with antagonistic activity will contribute to understand the antagonistic mechanism of Burkholderia sp. JP2-270.

Summary: The development of midbrain dopaminergic (mDA) neurons is controlled by multiple morphogens and transcription factors. However, little is known about the role of extracellular matrix proteins in this process. Here we examined the function of roof plate-specific spondins (RSPO1-4) and the floor plate-specific, spondin 1 (SPON1). Only RSPO2 and SPON1 were expressed at high levels during mDA neurogenesis, and the receptor LGR5 was expressed by midbrain floor plate progenitors. Surprisingly, RSPO2, but not SPON1, specifically promoted the differentiation of mDA neuroblasts into mDA neurons in mouse primary cultures and embryonic stem cells (ESCs). In addition, RSPO2 was found to promote not only mDA differentiation, but also mDA neurogenesis in human ESCs. Our results thus uncover an unexpected function of the matricellular protein RSPO2 and suggest an application to improve mDA neurogenesis and differentiation in human stem cell preparations destined to cell replacement therapy or drug discovery for Parkinson disease. : Gyllborg and colleagues report on the function of the matricellular protein R-Spondin 2 (RSPO2) in dopaminergic neuron development. RSPO2 is dynamically expressed during midbrain development and promotes the dopaminergic differentiation of mouse and human neuroblasts. Furthermore, they show that RSPO2 induced dopaminergic neurogenesis in human stem cell cultures, suggesting a possible application of RSPO2 in cell replacement strategies for Parkinson disease. Keywords: extracellular matrix, RSPO2, progenitors, dopaminergic neurons, differentiation, neurogenesis, human embryonic stem cells, Wnt, cell replacement, Parkinson disease

Surfactant assisted seedless synthesis of Ag-Ni alloy nanoparticles were carried out in an one step process by co- reduction of mixed metal salts (AgNO3 + Ni(NO3)2) solutions using ascorbic acid as reducing agent. To explore the role of surfactant, two types of surfactants were studied; cationic cetyltrimethylammonium bromide (CTAB) and anionic sodium dodecylbenzenesulphonate (SDBS). The surface plasmon resonance peak (SPR) of CTAB capped Ag-Ni and SDBS capped Ag-Ni located at 450 nm and 410 nm wavelengths, respectively. For SDBS, visual observations and time resolved spectra indicates that the reaction mixture containing different mixing orders of reactants (SDBS + Ag+ + Ni2+ + ascorbic acid and SDBS + Ni2+ + Ag+ + ascorbic acid) have different colours as well as different SPR band positions with time. Presence of SDBS delayed the nucleation processes. The Ag-Ni alloy with both surfactants shows that the a red shift to ca. 410 nm and 450 nm with respect to the SPR of AgNPs. The absence of SPR bands at ca. 375 nm and 500–700 nm ruled out the possibility to the formation and /or deposition NiO + Ni(OH)2 on the surface of Ag-Ni alloy. The average number of Ag-Ni atoms per nanoparticle, molar concentration of Ag-Ni and free energies (surface, volume and excess energy due to mixing) were calculated and discussed. The Ag-Ni alloy used as a catalyst to the photo-assisted degradation methyl orange and showed a higher photo catalytic activity. The synthetic method reported here suggests a very promising use of the suitable stabilizer for the preparation of an alloy nanoparticles having different optical properties, which is a subject of immense interest.

New hydrazones were synthesized by employing a convergent synthetic methodology involving condensation of N-alkyl 5-chloroisatins with hydrazone derived from 2-thiophenecarboxaldehyde. The synthesized compounds were fully characterized using UV/Vis., Infrared, 1H and 13C NMR spectroscopies as well as single crystal X-rays diffraction analysis. Bader's theory of ‘atoms in molecules’ confirmed the existence of all nonbonding interactions. Connectivity between isomers of synthesized compounds was characterized by the distribution of critical points, isatin surfaces, and bond paths. The presence of electrostatic potential on oxygen and hydrogen atoms was evaluated by means of MEP calculations, which showed that the oxygen atom acts as nucleophilic center for electrophilic hydrogen atom. Compound 6 exhibited potent anti-oxidant potential (DPPH, ABTS, NBT) with IC50 values of 46 ± 0.72 μM/mL. These compounds were also screened for in vitro cholinesterases inhibition, where compound 6 presented effective inhibition against AChE and BChE in comparison to the standard drugs; allanzanthane and galanthamine in a dose reliant mode. The IC50 values of both compounds (6 and 7) against AChE were determined to be 20.21 ± 0.06 & 16.22 ± 0.18 μM and against BChE, as 28.01 ± 0.01 & 20.11 ± 0.12 μM, respectively. Molecular docking studies supported these results and helped to establish structure activity relationship. The results reported in this manuscript are anticipated to be beneficial for understanding the solid-state architecture of the X-ray structures of new hydrazone conjugates of 5-chloroisatin & 2-thiophenecarboxaldehyde. On the other hand their intriguing biological potentials can create quest among scientific community to further analyze such molecules for drug discovery purposes.

Amine-functionalized chabazite (CHA) type silicoaluminophosphate (SAPO-34) materials were prepared under hydrothermal conditions by a direct co-condensation method. Different concentrations of an organo-amine (3-aminopropyltrimethoxysilane) were incorporated into the CHA-type framework under hydrothermal conditions. The crystalline structures of the organoamine modified SAPO-34 materials with different concentrations of amine functionalities were confirmed by powder XRD. The morphology of the materials was confirmed by SEM, FE-SEM, and TEM analysis. The successful incorporation of amine-functionalities into the wall of SAPO-34 framework was confirmed by 29Si and 13C magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy. The acidity and basicity of the materials was studied by NH3 and CO2 temperature programmed desorption (TPD). The resultant amine-functionalized SAPO-34 materials were utilized for the cyclo-addition of CO2 to epoxide in liquid phase medium. The organoamine-modified SAPO-34 acted as a bi-functional (acidic and basic) catalyst. The incorporated amine sites played a crucial role in CO2 activation on the surface, while the acidic sites of the SAPO-34 framework accelerated the epoxide ring opening. Thus, the amine-functionalized SAPO-34 prepared as described in this work can be an effective catalyst for the activation and utilization of CO2 in cyclic carbonate synthesis from epoxides (98%) conversion of epichlorohydrin with 96% selectivity toward cyclic carbonate.

It is a demand of present and future society to develop novel electrocatalysts for overall water splitting with reasonable overpotential and high current density to save environment and become tense from the shortage of fossil fuels. This strategy has boosted catalytic active sites via in situ growth of NiO & MoS2 in addition to nickel foam. The functional electrocatalyst motivated for the excellent activity to produce hydrogen evolution reaction (HER) at low overpotentials of MoS2/NiO. The Tafel slope for HER stands 37 mV/decade it has found excellent in terms of low overpotential practical application in basic media. The structure, morphology, and composition are studied by XRD, SEM, EDS, XPS & HRTEM techniques. The fascinating morphology might allow the fast diffusion of electrolyte towards electrode. A promising strategy of incorporating this simple, cost-effective to develop functional materials which can be exploited for other metal-based sulphides for energy conversion and for diverse applications. The proposed strategy for the preparation of MoS2/NiO nanostructures in the presence of MoSO2 and nickel foam is facile, mass production, could equally, participate for the realization of hydrogen gas production for the purpose of energy. The electro-catalyst is very stable for at least 18 hours. Also, these nanostructure MoS2/NiO) can be regarded as an alternative and promising materials for the different electrochemical applications including fuel cells, lithium ion batteries, overall water electrolysis and other energy storage devices.

Capable of achieving wide control over energy band gap and following optoelectronic properties; the highly mismatched alloys (HMAs) are considered to be promising materials for solar energy conversion devices. The dramatic restructuring of energy bands and density of states in HMAs caused by the replacement of anions with distinctly-mismatched isovalent constituents could further be an important course in improving their thermoelectric efficiency. In this paper, we attempt to explore and address the composition-induced modifications in the electronic band structure and the resultant effects on optical spectra and thermoelectric coefficients of GaN1−xSbx based HMAs in the framework of density functional theory. We observe, the substitution of N by Sb, considerably affects its band structure and split the conduction band minimum (CBM) into sub-bands. With increasing Sb composition, the lowest sub-band stemmed from N-s electrons has experienced drastic downward shift leading to energy gap narrowing. Interestingly, the energy gap narrowing along R- Γ is found to be faster than that of Γ- Γ point leading to an amazing direct to indirect band gap crossover. On the other hand, the composition-induced energy gap narrowing stimulates the red-shift in fundamental absorption edge in both ultraviolet and the infrared regime, making the GaNSb potentially useful material for photovoltaic applications. In addition, substantial effect on the thermoelectric coefficients of GaNSb is also observed via Sb substitution. We obtain larger Seebeck coefficient, improved power factors and figure of merit (ZT) for GaNSb at low Sb substitution and found diminishing effect with the further increase of Sb composition. With enhanced Seebeck coefficient, power factor and ZT values at modest doping levels, GaNSb alloy could be a promising candidate for near or above room temperature thermoelectric applications.

Cobalt carbonyl cluster was anchored through a facile route on the surface of organo-functionalized SBA-15 molecular sieve by post-synthetic approach. The successful grafting of organofunctional ligand and cobalt carbonyl cluster was evident thorough 29Si-MAS NMR, 13C-MAS NMR and FT-IR studies. The resultant cobalt clusters anchored functionalized SBA-15 material (SBA-15-RCo) showed promising catalytic activity on hydroformylation of 1-octene (97% conversion) with excellent selective towards hydroformylated products (90%).

Adsorptive removal of As(III) and As(V) by a binary Fe(III)–Sn(IV) mixed oxide-coated sand (ITOCS) has shown 89.33 and 93.59% efficiencies from their 500 μg/L solutions, respectively. Batch experiments were performed to optimize contact time, initial concentration, dosage, pH of solutions and temperature. The adsorption data was modeled by Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherms at 293, 303 and 313 K. Langmuir adsorption capacities were found to be 82.64 and 227 μg/g, for As(III) and As(V), respectively, at 8.0 g/L dosage, 60 min contact time at solution pH 7. The adsorption process followed pseudo-second order kinetics with film diffusion step controlling the mechanism. Gibbs free energy of adsorption of As(III) and As(V) was found to be −12.5 and −13.42 kJ/mol at 313 K, respectively. Negative values in both cases indicated spontaneous nature of the adsorption process. The values of enthalpy of adsorption were 4.763 and 33.82 kJ/mol for As(III) and As(V), respectively, suggesting endothermic nature of the adsorption process for both ions. The results indicated that ITOCS would find a good place as an adsorbent for the removal of arsenic from water.

Acetohydroxy acid synthase (AHAS)-inhibiting herbicides are one of the most commonly used herbicides for controlling the growth of Sagittaria trifolia L. in paddy fields in Northeastern China. In this study, we collected five suspected resistant populations of S. trifolia (R1-R5) from three different provinces of Northeastern China. The results of whole-plant bioassays revealed that those populations showed high level of resistance to bensulfuron-methyl with resistance index (GR50 R/S) ranging from 39.90 to 88.50. The results of AHAS-activity assays were consistent with the results of the whole-plant bioassays. The AHAS gene analysis showed that R2 and R3 populations contained Pro-197-Leu mutations that were highly resistant to penoxsulam; R1 and R4 populations contained Pro-197-Ser mutations that were highly resistant to bispyribac‑sodium; R5 population contained Trp-574-Leu mutation that showed high resistance to IMI, PT, PTB and SU herbicides. The AHAS with resistance mutations showed less sensitivity to feedback inhibition by BCAAs and R genotypes had increased free BCAAs.

Tin dioxide (SnO2) is the most important semiconductor material due to its large number of technological applications. In this work we carried out the electronic and optical properties under pressure of rutile SnO2. The ultra-soft pseudopotential method is used by employing the local density approximation functional proposed by Ceperley-Alder and Perdew-Zunger to calculate the exchange correlation potential within the framework of density functional theory. Firstly we optimized the structure to obtain the ground state energy of the system with the increase of cutoff energy (Fig. 1 (b)). The investigated band structure and density of states show that energy bandgap is increasing with the increase of pressure due to the movement of valence bands from higher to low energy levels and the conduction bands from lower to higher energy levels respectively (Fig. 1 (a)). The effect of pressure on lattice constants demonstrates the increase in lattice constants. Optical properties, comprising refractive index, dielectric function, absorption and energy loss spectrum are investigated. The obtained results are in good agreement with the previous reported theoretical and experimental results.

Preferential reduction of one of the two nitro groups in 3, 5-dinitrosalicylic acid monohydrate has been investigated using experimental charge density analysis from a high-resolution X-rays diffraction data at 100K combined with DFT theoretical calculations. The structure was refined using the classical Independent Atom Model as well as the Multipolar Atom Model. Bond characterization is performed in terms of charge density distribution and the associated topological properties. The theoretical (B3LYP/6-311++G(d,p), SMD/water) electrostatic potential molecular surfaces and atomic charges complimented the mechanism where one of the two nitro groups with higher negative charge gets preferentially reduced. The weak intermolecular interactions and hydrogen bonding are further quantified by the Hirshfeld surface analysis.

Crystal structures of co-crystal salt forms of anti-malarial drug pyrimethamine with benzoic acid in water solvent (I) and gallic acid in ethanol solvent (II) have been studied using X-ray diffraction data collected at room temperature. Refinement of crystal structures were carried out by independent atomic model (IAM), while the electrostatic properties were studied by transferring electron density parameters from an electron density database. Theoretically optimized hydrogen bond distances were used in the refinement procedures as they were found superior to the neutron diffraction distances. Results of both refinements were compared. Three dimensional Hirshfeld surface analysis and two dimensional fingerprint maps of individual molecules are dominated by H⋯H and O⋯H/H⋯O contacts. Topological analysis was carried out using Bader’s theory of Atoms In Molecules (AIM). Electrostatic properties such as dipole moment and electrostatic potential were calculated. Results of this study reveal that the co-crystal formation takes place due to N–H⋯O/N–H⋯O homosynthon. Quantitative and qualitative analysis shows that the synthon is robust one. Density functional theory (DFT) based calculations used to elucidate the factors which drive the co-crystallization, complement the experimental findings. The study highlights the significance of using multipolar parameters to understand the phenomena involved in crystal engineering.

Imidazole derivatives find wide scale and diverse applications. In this work two new imidazole based compounds have been synthesized. Their structures were confirmed using NMR, Mass Spectrometry and IR techniques. In addition, three dimensional structures were elucidated using single crystal X-rays diffraction analysis. The structures were refined using the classical independent atom model and the aspherical pseudo-atom model from an electron density database. The electrostatic properties and the topology of covalent bonds and intermolecular interactions of both the molecules were quantified on the basis of transferred electron density parameters. This study encourages the use of transferability principle for routine structure analysis as it gives better refinement statistics and reliable estimation of chemical reactivity through the study of electrostatic properties.

Baddeleyite TiO2 is one of the most important phases of titanium dioxide, from technological and industrial point of view. We have carried out theoretical investigation by using plane wave ultrasoft pseudopotential methods based on density functional theory. The Electronic band structure, elastic constants and optical properties as well as, the lattice parameters of baddeleyite TiO2 are calculated by using the optimized crystal structure. The bulk modulus, shear modulus, Young׳s modulus and Poisson ratios for baddeleyite TiO2 are also explored. The Debye temperature of baddeleyite TiO2 is investigated by using calculated mean sound velocity. The anisotropy ratios are computed from elastic constants. Our investigated elastic properties are in contrast with the previous reported results of Ma et al. (2009, Phys. Status Solidi B, 246 (9) 2132) by means of the same DFT method. Electronic properties are presented by considering the computed band structure and densities of states (DOS). Furthermore, the results of electronic properties are consistent with the available reported theoretical results. To explore the optical properties of baddeleyite TiO2, the dielectric functions, refractive index, absorption and energy loss spectrums are presented and analyzed by means of the electronic properties. Also, the considered DFT methods in this work are self-consistent.

Selection of a proper exchange and correlation potential for efficient treatment of excited-state properties such as the electronic band structure is required in density functional theory (DFT). We propose a simple and efficient Engel–Vosko generalized gradient approximation (GGA-EV) for calculating the electronic and optical properties of different phases of ZnO, namely, wurtzite, rock salt, zincblende and the CsCl-type structure. To validate our approach, we compare the results to those obtained using the local density approximation (LDA-PW91) and the parameterized generalized gradient approximation of Perdew et al. (GGA-PBE). We calculated the band structure, density of states, crystal field splitting energy, dielectric function, reflectivity, and absorption coefficient. GGA-EV yielded a wider valence band and narrower d-band in comparison to LDA-PW91 and GGA-PBE. Moreover, GGA-EV resulted in greater separation between Zn d and O p states, which reduced pd repulsion and consequently improved the energy band gap.

The electronic, elastic, acoustic and optical properties of cubic phases TiO2 fluorite and pyrite are investigated using the first principles calculations. We have employed five different exchange–correlation functions within the local density and generalized gradient approximations using the ultrasoft plane wave pseudopotential method. The calculated band structures of cubic-TiO2 elucidate that the TiO2 fluorite and pyrite are direct and indirect semiconductors in contrast to the previous findings. From our studied properties such as bulk and shear moduli, elastic constants C44 and Debye temperature for TiO2 fluorite and pyrite, we infer that both the cubic phases are not superhard materials and the pyrite phase is harder than fluorite. The longitudinal and transversal acoustic wave speeds for both phases in the directions [100], [110] and [111] are determined using the pre-calculated elastic constants. In addition, we also calculate the optical properties such as dielectric function, absorption spectrum, refractive index and energy loss function using the pre-optimized structure. On the observation of optical properties TiO2 fluorite phase turn out to be more photocatalytic than pyrite. & 2013 Published by Elsevier B.V.

The ultrasoft pseudopotential technique is used to explore the elastic, electronic and optical properties of cotunnite TiO2 using LDA and GGA proposed by Perdew Wang (PW91), Perdew–Burke–Ernzerhof (PBE) functional as defined by Wu and Cohen (PBEWC) and PBE functional for solids (PBESOL). The calculated elastic constants bulk modulus, shear modulus and Young’s modulus are in agreement with the previous theoretical reports. From our investigated shear anisotropy factors (A1 ,A 2, and A3), we infer that cotunnite TiO2 is strong anisotropy in case of A1 and A2 and less anisotropy in case of A3. The value of mean sound speed and Debye temperature are calculated using the obtained values of elastic moduli. The calculated structural parameters are in accord with the reported experiment and theoretical results. Our obtained values of direct bandgaps show an improvement over the other previous theoretical reports. The values of the dielectric constant (e1(o)) of cotunnite TiO2 calculated within LDA and GGA approximations are 7.655 (LDA (CA-PZ)), 7.578 (GGA (PW91)), 7.685 (GGA (WC)) and 7.655 (GGA (PBESOL)), which are slightly higher than the experimental values of rutile (6.69) and anatase (6.55) polymorphs. The obtained values of the refractive index are consistent with rutile TiO2 and higher than anatase phase. The investigated imaginary part of dielectric constant and absorption spectrum reflect that the cotunnite TiO2 is a weak photocatalytic material as compared to anatase and similar to rutile phases.

There is a significant worldwide demand for a small calibre vascular graft for use as a bypass or replacement conduit. An important feature in determining the success of a graft is the wall structure, which includes porosity, pore size and pore interconnectivity, as these play a crucial role in determining the long-term patency of a bypass graft. In this study we fabricate a small diameter (

Rationnelle Le but de cette etude etait de fabriquer un nouveau modele aortique avec des proprietes physiologiques, qui pourrait etre utilise pour l'etude a long terme de longevite des endoprotheses, selon les recommandations de la “Food and Drug Administration”. Methodes Des aortes abdominales porcines ont ete acquises pour etablir des valeurs de compliance. Le modele aortique etait fabrique en employant un polymere de nano composite. Une fausse aorte de latex a ete utilisee pour la comparaison. Un fantome pulsatile de flux a perfuse les aortes et les tubes synthetiques avec des pressions et un flux pulsatiles physiologiques. Les index diametral de compliance et de rigidite ont ete calcules a des pressions moyennes de 30 a 120 mm Hg. Les donnees ont ete analysees en employant l'analyse de la variance a sens unique et le test de Bonferroni. Resultats Les valeurs hemodynamiques du circuit etaient semblables pour l'aorte porcine et les tubes synthetiques. La compliance de l'aorte s'etendait de 2,97 ± 0,72 (moyenne ± ecart-type) a 1,42 × 10 −2 . ± 0,37%/mm Hg. Le modele de polymere a montre une meilleure compliance (extremes, 3,66 ±1,05-2,72 ± 0,28%/mm Hg × 10 −2 ; p p > 0,05). Il a egalement montre un comportement anisotrope semblable dans l'aorte. Les tubes de latex ont montre une compliance inferieure a l'aorte (extremes, 0,87 ± 0,24-0,86 ± 0,2%/mm Hg ×10 −2 ) et ont echoue par une distension significative sur l'augmentation de la pression moyenne de 90 mm Hg. Conclusions Nous avons developpe un modele aortique physiologique approprie avec une anatomie, une compliance, et une viscoelasticite compatibles, qui pourrait etre employe pour l'analyse de fatigue a long terme des stents et des greffes vasculaires. Les modeles d'aorte en latex peuvent echouer aux pressions physiologiques.

In situ formation of tungsten carbide in the matrix of FCC nickel has been achieved by carburizing of the electrodeposited Ni-W alloy coatings. The size of the carbide particles ranges between 100 and 500 nm. The carbide phase is also present in the form of very small precipitates inside the nickel grains. The size of such precipitates is between 10 and 40 nm. The carburizing environment was created by introducing a flowing mixture of vaporized 95.5% alcohol (0.25 ml/min, liquid) and argon (0.5 L/min, gas) into the carburizing furnace. Supersaturated nature of electrodeposited amorphous and nanocrystalline alloys, in addition to high diffusivity, have been attributed for the formation of carbide phase in the deposits at a temperature range of 700-850 degrees C. The carbide-metal interface is clean and the composite coatings are compact. Hardness values up to about 1100 KHN are achieved. Hardness increases with tungsten content and carburizing temperature. (C) 2009 Elsevier B.V. All rights reserved.

A density-functional theory study of structural and electronic properties of III-arsenide compounds BAs, AlAs, GaAs and InAs, is presented. For the exchange-correlation potential, local-density approximation (LDA) and generalized gradient approximation (GGA) have been used to calculate theoretical lattice parameters, bulk modulus, its pressure derivative, and cohesive energy. The electronic band structure of these compounds have been calculated by using the above two approximations as well as another form of GGA, proposed by Engel and Vosko (GGA-EV). The results obtained for structural and electronic properties are compared with experimental data and other computational work. It has been found that the energy bands with all these approximations are similar except band gap values. It has also been found that our results with LDA, GGA and GGA-EV are in good agreement with other computational work wherever these are available. Our results in general are also in agreement with the experimental values.

There is substantial amount of literature available in Pakistan focusing on wage level and trends in different sectors of the economy to determine labour market outcomes and differences in the living standard of workers. Man (2008) has shown that the time trend growth in wages for the last two and half decades has been 7.7 percent in contrast to 7.2 percent in prices thereby yielding 0.7 percent growth in real wages. This confirms that the purchasing power of consumers has remained very low due to surge in prices of commodities of consumer basket. Unfortunately the economy of Pakistan is facing multiple challenges, starting from its difficulty in arresting the escalation in prices, to achieving sustainable growth in a longer term horizon. There is virtually no improvement in socio-demographic indicators. The labour market dynamics are such that it is becoming increasingly difficult to train and educate people for work and to provide them with decent well-paying jobs. Resultantly, there is a dearth of educated and skilled people, and the mismatch between jobs and workers has increased. In this scenario, those who posses some sort of skills or specific education, they try to get maximum benefit out of it, including holding multiple jobs, even if it involves jobs in other than their own primary occupation. The moonlighting or holding of dual jobs has not been an attractive agenda of labour economists in Pakistan, even though it has been a common phenomenon in many developing countries. The subject is serious because it not only helps in understanding workers' behaviour and decision to allocate his/her time between work and leisure, moonlighting also affects the very structure of labour market including workers' performance and productivity. An in-depth analysis is therefore, required to know the significance of wage rate, demographics of the labour force, their budget constraints, their engagement in primary and secondary occupations, and above all their human capital characteristics. Given this ambitions agenda, it may not be possible to explore all these issues related with moonlighting in a single study. Therefore, the present study seeks to focus on three main research questions. The first and the main objective of the study is to find out the main determinants of dual job holding; Second, to explore the demographic and human capital characteristics of moonlighters; and lastly, to investigate relationship between workers' main occupation and second job. Within this perspective, the study may be regarded as a starting point to understand the complexities of labour market in Pakistan, particularly the job mobility, labour market transition and spillover over effects, if any.

Volumes of foams produced by sparging have been determined as a function of pH for dilute aqueous solutions containing a mixture of propylene glycol alginate (PGA) and a food protein (β-caScin, β-lactoglobulin, gelatin or soy protein) in the ratio 10:1 by weight. At a concentration insufficient to give significant foaming on its own, each protein gives an enhancement in the foaming capacity of PGA at pH 7. The order of effectiveness of the proteins is: β-casein > β-lactoglobulin > gelatin > soy protein. The results are consistent with the formation of a weak electrostatic complex between protein and polysaccharide at the air—water interface under neutral pH conditions.

The stability of transient foams produced at 25°C by shaking (i) whiskey and (ii) lager has been investigated as a function of the ethanol content. Maximum foam lifetimes occur at 40 wt% alcohol for bourbon whiskey and 0.8 wt% alcohol for ‘alcohol-free’ lager. Results are discussed in terms of the likely surface-active species present in each type of alcoholic beverage.

The influence of ethanol on the stability of foams formed from dilute aqueous solutions of four proteins (β-casein, lysozyme, β-lactoglobulin and gelatin) has been investigated at pH 7 and 25°C. Results were obtained using a shaking method, which, for solutions containing a volatile solvent, is shown to be preferable to a sparging method. Irrespective of protein type or concentration, we found a sharp increase in foam lifetime with small additions of ethanol, followed by a gradual fall with larger additions. The maximum foam stability occurs at 0.2–0.3 wt% alcohol. Relative stabilities of the foams formed from solutions of the four proteins lie in the order: gelatin ⪢ β-casein ⪢ β-lactoglobulin ⪢ lysozym