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Despite the growing salience of the Pakistan-China and US-Indian alliances, Pakistan-US relations continue to be a valuable enhancement both to stability and to Washington's influence in South Asia. The United States contributes to Pakistan's national security, just as Pakistan reciprocates in those areas where the U.S.-Indian relationship has its limitations. Pakistan also helps play a stabilizing effect on the US-China rivalry, despite Islamabad's close association with Beijing. [ABSTRACT FROM AUTHOR]

Among pretreatments existing to overcome the recalcitrance of the lignocellulosic biomass, imidazolium-based ionic liquids (ILs) are gaining interest to make cellulose more accessible to hydrolytic enzymes and generate fermentable sugars that are finally converted into ethanol by microbial fermentation. However, these pretreatments are usually implemented at a temperature between 80 °C and 160 °C raising realistically an energy demand problem. Here, we present an eco-friendly pretreatment strategy using the 1-ethyl-3-methylimidazolium acetate [Emim][OAc] IL at 45 °C. This energy efficient method was studied on three substrates: a model cellulose and two industrial forest residues, spruce and oak sawdusts. The viscosity of the three samples in [Emim][OAc] were followed depending on the temperature. The structures of the pretreated substrates were analyzed by scanning electron microscopy and by Fourier transform infrared spectra. Then the pretreated samples were submitted to enzymatic hydrolysis catalyzed by cellulases from Trichoderma reesei and to ethanolic fermentation by the yeast Saccharomyces cerevisiae. The ethanolic yields obtained from (ligno)cellulosic substrates were 2.6–3.9 times higher after the soft pretreatment with [Emim][OAc]. Thus, [Emim][OAc]-pretreatment at low temperature is a promising gentle method for LCB valorization into biofuels. Image 1 • [Emim][OAc]-pretreatment at 45 °C was assayed on 3 (ligno)cellulosic substrates. • The soft IL-pretreatment disorganized the lignocellulosic architectures. • Cellulases accessibility increased and enzymatic hydrolysis yields improved. • Ethanolic yields were 2.6–3.9 higher after the [Emim][OAc]-pretreatment at 45 °C. • This low energy demand IL-pretreatment is efficient on softwood and harwood. [ABSTRACT FROM AUTHOR]

The structural, electronic, and optical properties of inorganic indium-based halide perovskites with new composition InACl 3 (A = Ge, Sn, and Pb) are investigated in this work using density functional theory (DFT). These compounds are cubic in nature and their optimized lattice constants were found to be in the range 5.53–5.56 Å. The calculated band structure reveals that InGeCl 3 has direct bandgap nature while InSnCl 3 and InPbCl 3 are having indirect bandgap. The energy band gap values are found to be 1.89 eV, 0.87 eV and 1.84 eV for InGeCl 3 , InSnCl 3 and InPbCl 3 , respectively. This makes InGeCl 3 an attractive option as a Pb-free material for photovoltaic applications. The semiconducting energy gaps of InSnCl 3 and InPbCl 3 show their suitability for solar cells. The elastic constants C ij are calculated and analyzed for studying the mechanical response of studied compounds to external forces. For the photons of 0–20 eV energy range, optical parameters such as the real and imaginary parts of the dielectric function, refractive index, reflectivity, and absorption coefficient are computed and discussed. The simulation results for the studied compounds are reported for the first time in the literature. [ABSTRACT FROM AUTHOR]

A thin metal foil laminated on a polymer film usually fracture at higher strains than its corresponding freestanding material layer. On the contrary the polymer film can be observed to fracture at smaller nominal strains when laminated. This is due to the strain localization induced by the created localised neck and plastic deformation in the metal foil. A significant reduction of the “gauge length” of the polymer film is observed locally. This scenario prevails if the adhesion is sufficiently high to prevent delamination to grow between the layers. The newly created gauge length is in the order of two times a metal foil thickness if the adhesion is very strong, leading to local high stress and low strains measured globally. However, this effect is not due to the brittleness of the material or shift of mechanical properties during lamination. During stretching, large deformations are observed in the moderately ductile and strain-hardening polymer film. Tensile failure (boundary conditions and geometrical effects) of polymer laminates has been observed to be governed by two mechanisms demonstrated in Fig. 1. below. In the first case, the polymer film forms a neck and is deformed locally where the metal foil has fractured and ruptures at a small strain (I). In the second case, the delamination is grown and the polymer deforms and delocalizes the strain to a substantial larger area (II). In some cases the laminated material creates multiple necks and the metal film ruptures at several positions and thus deforms at larger strains. All these observations have experimentally been demonstrated by using scanning electron microscopic (SEM) micrographs. [ABSTRACT FROM AUTHOR]

Modern strawberry production is often threatened by microbe pathogens. Anthracnose is among the most prominent fungal disease caused mainly by Colletotrichum gloeosporioides and leads to large-scale losses both in quality and yield. Little is known regarding the mechanisms underlying the genetics in the strawberry- C. gloeosporioides interaction. In the current research, a wild accession ' Fragaria nilgerrensis ' is used as a resistant model to study the roles of terpenoid and terpene genes in leaf response to C. gloeosporioides. We found that several terpenoids and terpene genes were up-regulated at early time points after challenged with C. gloeosporioides. Among the metabolites detected, sesquiterpenes were the most significantly accumulated compounds, increasing up to ~12-fold at 18 h post infection (hpi), followed by monoterpenes which showed a slight increase upon infection. Consistently, the time-resolved transcriptome data revealed that genes pertaining to terpenoid metabolism were rapidly up-regulated and co-expressed with signaling pathway genes relevant to defense response. Notably, quantitative real-time PCR confirmed that the expression of five terpene synthase genes (TPS) were greatly enhanced, by a factor of one to three orders of magnitude at 3–6 hpi. Our results reveal a possible link between rapidly induced terpenoid metabolism and the autoimmunity underlying anthracnose resistance in a wild strawberry species. Image 1 • The wild strawberry Fragaria nilgerrensis is resistant to C. gloeosporioides , a causal agent of anthracnose disease. • Spray treatment of leaves with fungal spores induces rapid reprogramming in leaf metobolomics and transcriptome. • Rapid accumulation of terpenoids, particularly sesquiterpene compounds in challenged leaves is observed. • Genes encoding the MVA and MEP pathways as well as four terpene synthases are up-regulated at early as 3-6 hpi. • Terpenoid biosynthesis genes are co-expressed with genes of the host defense pathways. [ABSTRACT FROM AUTHOR]

Abstract: We report a detailed study of the electron emission from MgO and Y2O3 induced by the impact of 0.1–1keV Ar+ ions. The mechanisms of ion-induced secondary electron emission from oxides are far less understood because charging of the target surface during ion irradiation prohibits the precise measurement of electron yield. For this study, targets were prepared by depositing 20nm thick films of MgO and Y2O3 on the semi-conducting SnO2 substrate, which helps in charge neutralization. Additionally, a pulsed ion beam was used to further reduce the surface charging. It was found that the electron yield of both targets increases with energy of the ion. However, at a given ion energy the electron yield of Y2O3 was larger than MgO. Another important result of this study is that the electron emission from these large band gap insulators did not show any threshold effect, in contrast to the metal targets. It may be due to local reduction of the band gap through electron promotion processes. In addition, a Monte Carlo program was used to calculate the yield of secondary electrons excited by projectile ions, recoiling target atoms and electron cascades, and average escape depth of the secondary electrons emitted from the MgO and Y2O3 thin films. [Copyright &y& Elsevier]

The theoretical study is performed to investigate the structural, elastic, electronic and optical properties of Indium based fluoroperovskites InAF 3 (A = Ca, Cd, and Hg) based on the Density Functional Theory (DFT) using the Full-Potential Linearized Augmented Plane Wave (FP-LAPW) method implemented in WIEN2K. Generalized Gradient Approximation (GGA) with Hubbard term (GGA + U) is employed for the incorporation of exchange-correlation energy. The optimized lattice constants are found in the range of 4.51 Å to 4.69 Å. The calculated values of elastic constants show that compounds satisfy the stability criteria for a cubic system. It has also been observed that all the compounds are ductile and show anisotropic behavior. Calculated bandgaps of InCaF 3 and InCdF 3 are 3.66 eV and 3.29 eV, respectively, exhibiting direct band nature. The InHgF 3 is found to be an indirect bandgap material having the value of 1.59 eV. The significance of states contributed by each element is inferred from the total and partial density of state plots. The optical characteristics are discussed and analyzed in a broad energy range (with specific range shown 0–30 eV) using important parameters such as optical conductivity and reflectivity, refractive index, extinction coefficient, and absorption coefficient. The results are communicated for the first time for understudy Indium based compounds. [ABSTRACT FROM AUTHOR]