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This paper adopts the multi-criterion decision-making model of fuzzy-TODIM and genetic algorithm (GA) for optimal portfolio allocation. We applied Markowitz's portfolio parameters as inputs for the fuzzy TODIM model to rank stocks that are constituents of each index from three different markets. Portfolios are then generated dynamically using three weighting techniques and subject to multi-objective criteria and additional constraints. The results indicate a significant variation in performance metrics between the model-generated portfolios and the market indices. Replication of the procedure produces a similar outcome. Moreover, the out-of-sample tests conducted over 3 years validate the results' robustness, indicating that fuzzy TODIM, combined with GA, can achieve superior performance in dynamic portfolio allocation. [ABSTRACT FROM AUTHOR]

Ferroelectric materials exhibiting switchable and spontaneous polarization have strong potential to be utilized in various novel electronic devices. Solid solutions of different perovskite structures induce the coexistence of various phases and enhance the physical functionalities around the phase coexistence region. The construction of phase diagrams is important as they describe the material properties, which are linked to the underpinning physics determining the system. Here we present the phase diagram of (K0.5Na0.5NbO3)–(Ba0.5Sr0.5TiO3) (KNN-BST) system as a function of composition and their associated physical properties. Lead-free (1 − x)KNN–xBST (0 ≤ x ≤ 0.3) solid solution ceramics were synthesized by conventional solid-state reaction technique. The X-ray diffraction and Raman spectroscopic studies indicate composition-dependent structural phase transitions from an orthorhombic phase for x = 0 to orthorhombic + tetragonal dual-phase (for 0.025 ≤ x ≤ 0.15), then a tetragonal + cubic dual-phase (x = 0.2) and finally a cubic single phase for x ≥ 0.25 at room temperature (RT). Among these, the orthorhombic + tetragonal dual-phase system shows an enhanced value of the dielectric constant at room temperature. The phase transition temperatures, orthorhombic to tetragonal (TO-T) and tetragonal to cubic (TC), decrease with the increase in BST concentrations. The ferroelectric studies show a decrease of both 2Pr and EC values with a rise in BST concentration and x = 0.025 showed a maximum piezoelectric coefficient. [ABSTRACT FROM AUTHOR]

In this article, we present the results of low-temperature dielectric, magnetic and magnetodielectric properties of BiFeO3 nanoceramics prepared by auto-combustion method. Rietveld refinement results of X-ray diffraction data show that sample crystallizes in single-phase rhombohedral perovskite structure with R3c (No. 161) space group. The average crystallite size was found to be ≈ 600 Å from Williamson–Hall analysis. The temperature-dependent dielectric data have been presented in permittivity and modulus formalism to understand the relaxation dynamics. Three non-Debye-type relaxation processes were observed in the experimental window (173 to 423 K), which are explained using Kohlrausch–Williams–Watts (KWW) decay function. The temperature variation of relaxation times obeys Arrhenius's behaviour. The anomaly observed in the temperature dependence of relaxation times data near 240 K corresponds to the magnetic transition of BiFeO3. We found that single ionized oxygen vacancies with activation energy ranging from 0.4 to 0.8 eV are involved in the relaxation process. A crossover from AFM/PM to weak ferromagnetic ordering is observed at low temperature. The variation of capacitance with an applied magnetic field shows a hysteresis effect. The magnetocapacitance (MC%) changes by 3% at a magnetic field of 2 T for 200 kHz, indicating an intrinsic bulk magnetocapacitance effect in the ceramics. Hence, the above findings highlight the significance of the material as a potential candidate for device applications. [ABSTRACT FROM AUTHOR]

Compound extreme events, such as flash drought, have received wide attention in recent decades due to their far-reaching effects on the ecosystem. Thus, a new concept of flash drought has begun to spread globally in the scientific community, and it is continuously being developed. This study offers for the first time an overview of the global trends in flash drought research from 2000 to 2021. The analysis was based on the Scopus database in order to investigate the publication trends, contributions, collaborations, and challenges on a global scale. Furthermore, collaboration analysis was performed to detect collaboration networks within the flash drought research field. A total of 76 studies were published during the study period. The research output grew exponentially with an average growth rate of 30% per year. The challenging issues in the field of flash drought research are the search for appropriate definition of flash drought, the development of effective early warning systems and the scarcity of high-resolution data. By presenting the details of the evolution of this new conceptualization in drought research, our study highlights the main pathways of scientific progress and stimulates future research. [ABSTRACT FROM AUTHOR]

Inspired by massive parallelism, an increase in internet-of-things devices, robust computation, and Big-data, the upsurge research in building multi-bit mem-transistors is ever-augmenting with different materials, mechanisms, and state-of-the-art architectures. Herein, we demonstrate monolayer WS2-based functional mem-transistor devices which address nonvolatility and synaptic operations at high temperature. The ionotronic memory devices based on WS2 exhibit reverse hysteresis with memory windows larger than 25 V, and extinction ratio greater than 106. The mem-transistors show stable retention and endurance greater than 100 sweep cycles and 400 pulse cycles in addition to 6-bit (64 distinct nonvolatile storage levels) pulse-programmable memory features ranging over six orders of current magnitudes (10−12–10−6 A). The origin of the multi-bit states is attributed to the carrier dynamics under electrostatic doping fluctuations induced by mobile ions, which is illustrated by employing a fingerprint mechanism including band-bending pictures. The credibility of all the storage states is confirmed by obtaining reliable signal-to-noise ratios. We also demonstrate key neuromorphic behaviors, such as synaptic plasticity, near linear potentiation, and depression, rendering it suitable for successful implementation in high temperature neuromorphic computing. Furthermore, artificial neural network simulations based on the conductance weight update characteristics of the proposed ionotronic mem-transistors are performed to explore the potency for accurate image recognition. Our findings showcase a different class of thermally aided memories based on 2D semiconductors unlocking promising avenues for high temperature memory applications in demanding electronics and forthcoming neuromorphic computing technologies. [ABSTRACT FROM AUTHOR]

In this article, we report dielectric behavior and current–voltage characteristics of manganese (Mn)-doped zirconia nanocomposite in the 298 < T < 523 K temperature range. It is observed that the electrical response is controlled by the Mn concentration present in the sample. Both ac and dc conductivities of the prepared samples are observed to increase as the temperature rises. This suggests that the prepared samples behave in a semiconducting nature. Also, the ac conductivities of the samples increase with the frequency, which is prominent beyond the hopping frequency. The complex dielectric permittivity decreases with frequency and attains saturation at high-frequency regions. The current–voltage study shows that trap height increases with temperature and sample behavior is governed by the Poole Frenkel Emission model. [ABSTRACT FROM AUTHOR]

The single-phase (HfxZr0.8−x) (Ta0.1Dy0.1) O2 with 0.2 ≤ x ≤ 0.6 ceramics were synthesized by conventional solid-state reaction. The structural and morphological/microstructural characteristics were studied using x-ray diffraction and scanning electron microscopy, respectively. The dielectric properties and electrical conductivity of the bulk material were investigated as a function of temperature and frequency in the metal–insulator–metal configuration. The room-temperature dielectric constant at 100 kHz was found to be in the range of 17–35, along with low dielectric loss < 0.02. The leakage current densities at 3 kV/cm were 3.085 × 10−5, 1.67 × 10−5, and 3.93 × 10−6 A/cm2 for (Hf0.2Zr0.6)(Ta0.1, Dy0.1) O2, (Hf0.4Zr0.4)(Ta0.1, Dy0.1)O2, and (Hf0.6Zr0.2)(Ta0.1Dy0.1)O2, respectively. The frequency dependence of ac conductivity obeyed the Jonscher power law, suggesting hopping-based conduction. [ABSTRACT FROM AUTHOR]

Heat shock transcription factors (Hsfs) play an essential role as transcriptional regulatory proteins against heat stress by controlling the expression of heat-responsive genes. Common bean is a highly thermosensitive crop, and, therefore, its genome sequence information is segregated, characterized here in terms of heat shock transcription factors and its evolutionary significance. In this study, a complete comprehensive set of 29 non-redundant full-length Hsf genes were identified and characterized from Phaseolus vulgaris L. (PvHsf) genome sequence. Detailed gene information such as chromosomal localization, domain position, motif organization, and exon–intron identification were analyzed. All the 29 PvHsf genes were mapped on 8 out of 11 chromosomes, indicating the gene duplication occurred in the common bean genome. Motif analysis and exon–intron structure were conserved in each group, which showed that the cytoplasmic proteins highly influence the conserved structure of PvHsfs and heat-induced response. The HSF genes were grouped into three classes, i.e., A to C and 14 groups, based on structural features and phylogenetic relationships. Only one pair of paralog sequences suggests that it may be derived from the duplication event during evolution. A comparative genomics study indicated the influence of whole-genome duplication and purifying selection on the common bean genome during development. In silico expression analysis showed the active role of class A and B family during abiotic stress conditions and higher expression in floral organs. The qRT-PCR analysis revealed PvHSFA8 as the master regulator and PvHSFB1A and PvHSFB2A induction during heat exposure in French beans. [ABSTRACT FROM AUTHOR]

Multiferroic composites are promising candidates for magnetic field sensors, next-generation low power memory and spintronic devices, as they exhibit much higher magnetoelectric (ME) coupling and coupled ordering parameters compared to the single-phase multiferroics. Hence, the 3-0 type particulate multiferroic composites having general formula (1 − Φ)[PbFe0.5Nb0.5O3]-Φ[Co0.6Zn0.4Fe1.7Mn0.3O4] (Φ = 0.0, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 1.0, (1 − Φ) PFN-ΦCZFMO) were prepared using a hybrid synthesis technique. Preliminary structural and microstructural analysis were carried out using XRD and FESEM techniques, which suggest the formation of 3-0 type particulate composite without the presence of any impurity phases. The multiferroic behaviour of the composites is studied with polarization versus electric field (P-E) and magnetization versus magnetic field (M-H) characteristics at room temperature. The nature of ME coupling was investigated elaborately by employing the Landau free energy equation along with the magneto-capacitance measurement. This investigation suggests the existence of biquadratic nature of ME coupling (P2M2). The magneto-electric coupling measurement also suggests that strain mediated domain coupling between the ferroelectric and magnetic ordering is responsible for the magneto-electric behaviour. The obtained value of direct ME coefficient 26.78 mV/cm-Oe for Φ = 0.3, found to be higher than the well-known single-phase materials and polycrystalline composites. [ABSTRACT FROM AUTHOR]

One of the ways to mitigate the world energy crisis is to harvest clean and green energy from waste-heat, which is abundant, ubiquitous, and free. Energy harvesting of this waste-heat is one of the most encouraging methods to capture freely accessible electrical energy. Ferroelectric materials can be used to harvest energy for low power electronic devices, as they exhibit switchable polarization, excellent piezoelectric and pyroelectric properties. The most important characteristic of ferroelectric materials, in the context of energy harvesting, is their ability to generate electric power from a time-dependent temperature change. In this work, we grew highly c-axis oriented heterostructures of BaZr0.2Ti0.8O3 (barium zirconium titanate, BZT)/Ba0.7Ca0.3TiO3 (barium calcium titanate, BCT) on SrRuO3 (strontium ruthenate, SRO) and deposited on SrTiO3 (strontium titanate, STO) single crystalline substrate using pulsed laser deposition (PLD) technique. We investigated the structural, electrical, dielectric, and pyroelectric properties of the above-mentioned fabricated heterostructures. The wide range of θ–2θ X-ray diffraction (XRD) patterns only shows (00l) reflection peaks of heterostructures and the substrate which confirmed that the films are highly c-axis oriented. We are also capable to convert the low-grade waste-heat into electrical energy by measuring various temperature-dependent ferroelectric hysteresis loops of our nanostructure films via pyroelectric Ericsson cycles and the structures show an energy conversion density ~ 10,970 kJ/m3 per cycle. These devices exhibit a large pyroelectric current density of ~ 25 mA/m2 with 11.8 °C of temperature fluctuation and the corresponding pyroelectric coefficient of 3425 μC/m2K. Our research findings suggest that these lead-free relaxor-ferroelectric heterostructures might be the potential candidates to harvest electrical energy from waste low-grade thermal energy. [ABSTRACT FROM AUTHOR]

The drawbacks of common anodes in lithium-ion batteries (LIBs) and hybrid supercapacitors (HSCs), such as the high voltage plateau of Li4Ti5O12 (1.55 V vs. Li/Li+) and the moderate capacity of graphite (372 mAh-g-1), have established a need for better materials. Conversion materials, and in particular iron oxide and CaFe2O4 (CFO), have amassed recent attention as potential anode replacements. In this study, we evaluate the material and electrochemical effects of the solution combustion synthesis (SCS) of porous CFO across novel fuel-to-oxidizer ratios and calcination temperatures. We demonstrate that nearly doubling the amount of fuel used during synthesis increases capacities between 120 and 150% at high current densities (~ 1000 mA-g-1) and across 500 additional charging-discharging cycles, an effect brought on in part by enhanced compositional purity in these samples. However, in order to ensure long-term cyclic stability, it is necessary to also calcine porous CFO to 900 °C to enhance crystallite size, particle size and spacing, and compositional purity. [ABSTRACT FROM AUTHOR]

Raman scattering and ab initio Raman/phonon calculations, supported by X-ray diffraction, are combined to study the vibrational properties of Zn1−xBexTe under pressure. The dependence of the Be–Te (distinct) and Zn–Te (compact) Raman doublets that distinguish between Be- and Zn-like environments is examined within the percolation model with special attention to x ~ (0,1). The Be-like environment hardens faster than the Zn-like one under pressure, resulting in the two sub-modes per doublet getting closer and mechanically coupled. When a bond is so dominant that it forms a matrix-like continuum, its two submodes freely couple on crossing at the resonance, with an effective transfer of oscillator strength. Post resonance the two submodes stabilize into an inverted doublet shifted in block under pressure. When a bond achieves lower content and merely self-connects via (finite/infinite) treelike chains, the coupling is undermined by overdamping of the in-chain stretching until a «phonon exceptional point» is reached at the resonance. Only the out-of-chain vibrations «survive» the resonance, the in-chain ones are «killed». This picture is not bond-related, and hence presumably generic to mixed crystals of the closing-type under pressure (dominant over the opening-type), indicating a key role of the mesostructure in the pressure dependence of phonons in mixed crystals. [ABSTRACT FROM AUTHOR]

This work reports on the dielectric and electrical properties of a single-phase polycrystalline pyrochlore structured Gd2Zr2O7 ceramics with a highly dense and compact microstructure. X-ray diffraction along with Raman spectroscopic studies confirmed the formation of the pyrochlore phase; while the electron microscopy investigations showed the uniformly distributed and densely packed micrometer-sized grains. The relaxation phenomena and conduction processes in Gd2Zr2O7 analyzed using complex impedance spectroscopy which showed the appearance of low-frequency dielectric dispersion suggesting the dominance of conduction by oxygen ions. Observation of double semi-circular arcs in the Nyquist plots confirms that both grains and grain boundaries contribute to the electrical impedance of Gd2Zr2O7. The temperature-dependent ac conductivity studies on Gd2Zr2O7 followed the Jonscher's power law exhibited a strong dispersive behavior at the low temperature (< 300 °C) over the whole frequency region; whereas a weak dispersive nature observed at the higher temperature in the higher frequency region. An enhanced conductivity with relaxation phenomenon at elevated temperature is attributed to the transition from prolonged hopping to short-range ionic transportation. The increase in the ac conductivity with temperature reveals that Gd2Zr2O7 pyrochlore has a negative coefficient of resistance. Because of the good control of the electrical transport properties of Gd2Zr2O7 ceramic on its structure, it could be further exploited for the development of advanced solid-electrolytes for solid oxide fuel cells. [ABSTRACT FROM AUTHOR]

The generic 1-bond → 2-mode "percolation-type" Raman signal inherent to the short bond of common A1−xBxC semiconductor mixed crystals with zincblende (cubic) structure is exploited as a sensitive "mesoscope" to explore how various ZnSe-based systems engage their pressure-induced structural transition (to rock-salt) at the sub-macroscopic scale—with a focus on Zn1−xCdxSe. The Raman doublet, that distinguishes between the AC- and BC-like environments of the short bond, is reactive to pressure: either it closes (Zn1−xBexSe, ZnSe1−xSx) or it opens (Zn1−xCdxSe), depending on the hardening rates of the two environments under pressure. A partition of II–VI and III–V mixed crystals is accordingly outlined. Of special interest is the "closure" case, in which the system resonantly stabilizes ante transition at its "exceptional point" corresponding to a virtual decoupling, by overdamping, of the two oscillators forming the Raman doublet. At this limit, the chain-connected bonds of the short species (taken as the minor one) freeze along the chain into a rigid backbone. This reveals a capacity behind alloying to reduce the thermal conductivity as well as the thermalization rate of photo-generated electrons. [ABSTRACT FROM AUTHOR]

Accurate estimation of evapotranspiration is generally constrained due to lack of required hydrometeorological datasets. This study addresses the performance analysis of reference evapotranspiration (ETo) estimated from NASA/POWER, National Center for Environmental Prediction (NCEP) global reanalysis data before and after dynamical downscaling through the Weather Research and Forecasting (WRF) model. The state-of-the-art Hamon's and Penman-Monteith's methods were utilized for the ETo estimation in the Northern India. The performance indices such as bias, root mean square error (RMSE), and correlation (r) were calculated, which showed the values 0.242, 0.422, and 0.959 for NCEP data (without downscaling) and 0.230, 0.402, and 0.969 for the downscaled data respectively. The results indicated that after WRF downscaling, there was some marginal improvement found in the ETo as compared to the without downscaling datasets. However, a better performance was found in the case of NASA/POWER datasets with bias, RMSE, and correlation values of 0.154, 0.348, and 0.960 respectively. In overall, the results indicated that the NASA/POWER and WRF downscaled data can be used for ETo estimation, especially in the ungauged areas. However, NASA/POWER is recommended as the ETo calculations are less computationally expensive and easily available than performing WRF simulations. [ABSTRACT FROM AUTHOR]

A series of phosphate based phosphors NaCd1−xPO4: xDy3+(x = 0.02–0.1) are prepared by adopting conventional solid state reaction routes. The prepared phosphors are well characterized by x-ray diffraction to establish the phase purity while a field emission scanning electron microscope is used to detect the microstructure. The surface chemical composition, an important aspect of this work, is established by x-ray photoelectron spectroscopy. The photoluminescence excitation spectra are recorded at room temperature, in which the excitation maxima are observed at 347 nm, indicating a near ultraviolet (UV) excitation which can be useful for light emitting diodes with a UV chip. The emission spectra show three major emission lines at 480 nm (4F9/2 → 6H15/2) a blue emission, a yellow emission around 570 nm (4F9/2 → 6H13/2) and a red emission around 662 nm (4F9/2 → 6H11/2). The CIE 1931 color chromaticity diagram shows the color coordinates around (0.32, 0.31) and such phosphors can be useful for solid state lighting applications as the emission spectrum lies in the near white region in the color space. [ABSTRACT FROM AUTHOR]

We demonstrate in detail the influence of divalent non-magnetic metal ion Zn on the structural, magnetic ordering as well as the dielectric dynamics of nano-sized LaFeO3. Introduction of Zn at Fe site distorts the FeO6 octahedron near it evidencing from a shift in the most intense peak towards lower angle. Subsequent broadening of peaks signifies a lower particle size which is further supported by micrographs. With field history, temperature-dependent magnetization shows that the doped samples acquire a non-ergodic state at low temperature and the incompleteness of the phase transition even at very high temperature. The isothermal magnetization depicts a significant increase in magnetization at higher field with a decrease in coercivity. Extensive impedance and electrical modulus analysis are carried out to know the exact conduction process and relaxation mechanism adopted by the doping system. Impedance spectra reveal a non-Debye type of relaxation mechanism and with increase of Zn concentration and temperature, grain boundary effect dominates over grain effect. This grain and grain boundary effect is further confirmed through electrical modulus Nyquist plots. The activation energy values of grain and grain boundary are 0.37 eV and 0.47 eV for x = 0.1, 0.37 eV, 0.40 eV for x = 0.2 and 0.28 eV, 0.38 eV for x = 0.3, respectively. Accordingly, the doping system agreed with a p-type polaronic hopping. Furthermore, the frequency-dependent electrical conductivity data are explained in the framework of both Jonscher power law and Jump relaxation model. [ABSTRACT FROM AUTHOR]

Combining two materials in a nanoscale level can create a composite with new functionalities and improvements in their physical and chemical properties. Here we present a high-throughput approach to produce a nanocomposite consisting of metal nanoparticles and semiconductor oxide nanostructures. Volmer-Weber growth, though unfavorable for thin films, promotes nucleation of dense and isolated metal nanoparticles on crystalline oxide nanostructures, resulting in new material properties. We demonstrate such a growth of Au nanoparticles on SnO2 nanostructures and a remarkable sensitivity of the nanocomposite for detecting traces of analytes in surface enhanced Raman spectroscopy. Au nanoparticles with tunable size enable us to modify surface wettability and convert hydrophilic oxide surfaces into super-hydrophobic with contact angles over 150°. We also find that charge injection through electron beam exposure shows the same effect as photo-induced charge separation, providing an extra Raman enhancement up to an order of magnitude. [ABSTRACT FROM AUTHOR]

The metal-to-insulator transition (MIT) closest to room temperature of 68–70 °C as shown by vanadium oxide (VO2), compared with other transition metal oxides, makes it a potential candidate for smart window coating. We have successfully fabricated a potential smart window device after the optimum design of a multilayered thin film structure made out of transparent conducting oxide (aluminum doped zinc oxide) and pure VO2 using pulsed laser deposition technique. This comprehensive study is based on two different configurations for multi-layered structure approach, with the intention to reduce the transition temperature, as well as to maintain the MIT properties that would strengthen the potential of the structure to be used for a smart window device. By creating a multi-layered structure, we were able to create a low powered device that can operate less than 15 V that leads to significant decline in the infrared transmission by a magnitude of over 40% and provided sufficient heat to trigger the MIT at a temperature around 60 °C, which is almost 10 °C lower than its bulk counterpart. This finding would positively impact the research on VO2 thin films, not only as smart windows but also for numerous other applications like bolometers, infrared detectors, Mott transistors and many more. [ABSTRACT FROM AUTHOR]

Large area highly crystalline MoS2 and WS2 thin films were successfully grown on different substrates using radio-frequency magnetron sputtering technique. Structural, morphological and thermoelectric transport properties of MoS2, and WS2 thin films have been investigated systematically to fabricate high-efficient thermal energy harvesting devices. X-ray diffraction data revealed that crystallites of MoS2 and WS2 films are highly oriented in 002 plane with uniform grain size distribution confirmed through atomic force microscopy study. Surface roughness increases with substrate temperature and it plays a big role in electron and phonon scattering. Interestingly, MoS2 films also display low thermal conductivity at room temperature and strongly favors achievement of higher thermoelectric figure of merit value of up to 1.98. Raman spectroscopy data shows two distinct MoS2 vibrational modes at 380 cm−1 for E12g and 410 cm−1 for A1g. Thermoelectric transport studies further demonstrated that MoS2 films show p-type thermoelectric characteristics, while WS2 is an n-type material. We demonstrated high efficient pn-junction thermoelectric generator device for waste heat recovery and cooling applications. [ABSTRACT FROM AUTHOR]

The present work is focused on the effects of graphene addition on the electrochemical performance of environmentally benign nanostructured graphene–nickel–phosphorus composite coating (G–NiP) on copper developed by electroless deposition. The coatings were developed using no external dispersing agents and toxic reductant such as hydrazine. The electrochemical corrosion behavior of the coating was investigated using potentiodynamic polarization (PDP) measurement. The anodic polarization curves of the Ni–P coating on copper (Cu–NiP) show two distinct active–passive regions and an oxidation peak, whereas graphene Ni–P coating (Cu–G–NiP) shows almost passive behavior. For Cu–NiP at critical pitting potential (Ec), the passivation breaks indicating initiation of pits, whereas Cu–G–NiP shows the absence of Ec. The PDP results also demonstrate the enhanced corrosion resistance property of the Cu–G–NiP with corrosion inhibition efficiency of 95%. The electrochemical impedance spectroscopy was used to analyze the physical and electrochemical process occurring at various interfaces and to study the influence of graphene in the coating under a corrosive environment. The higher density of micropores is evident from the FESEM image of Cu–NiP, whereas comparatively fewer micropores are observed in the case of Cu–G–NiP after the electrochemical test. This study also reveals that the addition of graphene in the Ni matrix inhibits pore creation and pit formation leading to better intactness of the coating. [ABSTRACT FROM AUTHOR]

Extreme weather events like tropical cyclone result in colossal catastrophe during landfall causing widespread inland flooding due to storm surge and also the post-landfall event result in extensive damage to infrastructural facilities and property hinterland. The state of Odisha located in east coast of India experienced a Very Severe Cyclonic Storm (VSCS) named Phailin during the post-monsoon season of October 2013. Timely warnings and alertness on storm surge coordinated with a massive evacuation effort by National Disaster Management Authorities (NDMA) were quite effective in minimizing the loss of human life. However, there was a trial of destruction due to extremely high winds and rainfall that followed during post-landfall causing extensive damage to property and major infrastructure facilities in the Odisha State. This study critically investigated the Phailin post-landfall phase focusing on the impact of high winds and rainfall on the power distribution network using the Weather Research and Forecasting (WRF) model. The study evaluated the spatial and temporal variability of wind speed and rainfall distribution from the WRF model configured for three different spatial domains and selecting the best available microphysics and land surface parameterization schemes. The proposed outer, intermediate, and inner domains had spatial resolutions of 27, 9, and 3 km respectively and that provided the best estimate for onshore wind speed, track forecast, and rainfall distribution highly relevant for the management of power distribution and transmission network. In context to weather model application for the Indian region, this effort is novel and probably for the first time that linked a suitable customized weather model output to evaluate its impact on observed tripping in transmission network of electric power grids. The dynamic model outputs from WRF were compared with data from synchrophasors used in electrical technology that monitored the transient and dynamic behavior of power systems in real-time operations. A close examination of the results signifies that the atmospheric model performed exceptionally well in capturing the tripping time of power lines, and the overall knowledge obtained from this study has a broader scope to develop a framework for efficient planning operations of the power network, resource allocation, and emergency preparedness. [ABSTRACT FROM AUTHOR]

We report the electrothermal properties of AAA trilayer on polyethylene terephthalate substrate which allowed the development of low-cost high-performance transparent thin-film flexible heater (TTFFH) using RF magnetron sputtering. The structural, electrical, and optical properties of the AAA trilayer were investigated at different thickness of the Ag interlayer. The AAA trilayer-based TTFFH yielded saturation temperatures beyond 100 °C at 10 V at optimized Ag interlayer thickness of 5 nm. The time-dependent temperature profile along with its highly stable and reversible thermal behavior was studied. Most importantly, the AAA trilayer-based TTFFH provides a high-performance alternative to the conventional and expensive ITO electrodes at a much lower cost. [ABSTRACT FROM AUTHOR]

This paper presents the mixed mode propagation of circular delamination pre-embedded at the interface of 1st and 2nd plies of wingskin adherend of the Spar Wingskin Joint made with curved fibre reinforced plastic composite panels. Three dimensional finite element analyses of these joints under uniformly applied out of plane transverse load have been carried out using contact and multi point constraint elements. The growth of embedded delamination is simulated by sequential release of the constraints of these elements ahead of the delamination front. The inter-laminar stresses and strain energy release rate values being indicative parameters in delamination growth studies are computed in the vicinity of the curved delamination fronts. These values are evaluated using virtual crack closure technique. It has been observed that the circular delamination size significantly influences the magnitudes of inter-laminar stresses and the three components of SERR values in the vicinity of delamination front. Maximum values of peel stress and mode I SERR occur at orthogonal locations to the loading direction i.e. at θ = 90° and 270° measured counter clockwise from positive X-axis along the periphery of the delamination fronts. The variations of inter-laminar stresses and the values of SERR are non-uniform along the circular delamination front indicating variable rates of propagation. This simulation procedure will be used for the assessment of loss of structural integrity of the SWJs having circular delamination when the embedded delamination undergoes propagation upon increase of loading. [ABSTRACT FROM AUTHOR]

In this research, we demonstrate a cost-effective method of developing a high temperature transparent heater by creating mesoscale (1-5 μm diameter) silver (Ag) wire network on glass. A colloidal solution of ethanol and cerium oxide (CeO2) is used to create a sacrificial template onto which Ag (100 nm) was deposited using electron beam (EB) evaporation. EB deposition parameters are critically optimized so that Ag wires are annealed instantly having rigid adherence to the substrate surface. A highly interconnected and continuous Ag network is obtained exhibiting transmittance up to 70% and sheet resistance of 1.13 Ω/sq, making it suitable for optoelectronic applications. This transparent conductor serves as a transparent heater when a DC voltage is applied to it, generating temperatures more than 200 °C at an operating voltage of just 4 V. This unique electro-thermal property can be attributed to the triangular junctions of Ag wire network that act as a micro-welding centers which impede the transport current path, favoring resistive Joules heating. [ABSTRACT FROM AUTHOR]

We report the preparation of ferroelectric Ba0.7Ca0.3TiO3 (BCT) ceramics by sol-gel auto combustion technique and its specific functional properties. The structural, dielectric and ferroelectric properties of BCT are strongly depending on the sintering temperature which also improves the phase purity and crystalline quality of the system. The formation of single-phase BCT is realized by sintering at 1450 °C for 4 h. suggesting the solubility limit of Ca2+ cation. Grain size and relative density are increased as the sintering temperature increased. The Rietveld refinement technique is employed for the detailed crystal structural analysis. The temperature and frequency dependent dielectric properties are investigated; the measured dielectric constant is εr = 2680 at the transition temperature Tc=120 °C for the single phase ferroelectric BCT. Sintering and electrical poling improved the shape of the hysteresis curve and reduced the leakage current. Electrical conduction mechanism is also discussed. [ABSTRACT FROM AUTHOR]

In the present work, corrosion-resistant and hydrophobic nickel-reduced graphene oxide (Ni-RGO) composite coating prepared by electroless deposition technique on mild steel (MS), without the use of toxic chemicals, is reported. The field emission scanning electron microscopy micrographs show a uniform composite coating of Ni-RGO with smaller grain size, whereas cuboidal and larger grains were observed in the case of Ni coating on MS. A reduction in crystallite size from 30 to 13 nm with the incorporation of RGO to the Ni matrix was estimated from XRD. The corrosion activity was investigated with potentiodynamic polarization and electrochemical impedance spectroscopy measurements. The surface of Ni-RGO composite coating remained intact, almost undamaged and showed a robust resistance to corrosion with an inhibition efficiency of about 95% in aggressive 3.5 wt.% NaCl solution. Nanoindentation test revealed that the hardness and Young’s modulus of Ni-RGO composite coating are increased by about 25 and 19%, respectively, as compared to Ni coating. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

Ferroelectric polymer nanocomposites of poly(vinylidene fluoride) (PVDF) and Mg doped PZT (PMZT) have been prepared by solvent casting method. The existence of β, γ and δ polar phases and α nonpolar phase of PVDF have been observed from the X-ray diffraction (XRD) and FTIR analysis. Both rhombohedral as well as tetragonal crystal phases of PZT at morphotropic phase boundary (MPB) is also observed. The characteristic peaks of PVDF in the FTIR spectra are unaffected with the incorporation of PMZT. Dielectric properties were studied as a function of frequency and temperature. The microstructure of PVDF-PMZT composite has been studied by employing SEM technique. Maximum dielectric constant of 32 with minimum dielectric loss of 0.0053 were obtained at 100 kHz for 6 mol% PMZT composite. The ac conductivity follows the Jonscher power law which exhibits the least value of interaction between mobile ions and lattice. Both grain and grain boundary contributions have been considered to explain the impedance behavior of the sample. The optimum loading percentage of PMZT in PVDF matrix is found to be 6 mol%. The structural results obtained from XRD and FTIR are well correlated with the physical parameters obtained from impedance measurement. [ABSTRACT FROM AUTHOR]

The lead magnesium niobate (PMN; PbMg1/3Nb2/3O3) and bismuth ferrite (BFO; BiFeO3) electronic compound has been fabricated and its excitation through electric field has been experimentally investigated. The unveiled excellent material properties like frequency independent and temperature dependent high dielectric constant and low dielectric loss substantiate the relaxor behavior of the processed material. A parallel plate capacitor structure is designed in order to reveal the material’s excitation through the generated internal electric field which has also been affirmed. The experimental results exhibit the dependence of excitation intensity on the material properties, driving frequency, relative position and generated electric field strength. The intensity of excitation attains its peak when the driving frequency is synchronized with the mechanical resonant frequency of the fabricated relaxor dielectric component. [ABSTRACT FROM AUTHOR]

Neodymium-doped lead zirconate tianate, i.e. Pb1−xNdxZr0.52Ti0.48O3 (PNZT) ceramics, with x = 0-10 mol.% has been prepared by the sol-gel process. X-ray diffraction pattern at room temperature shows the pyrochlore free phase for all samples. The structural analysis suggests the coexistence of both rhombohedral (R3m space group) and tetragonal (P4 mm space group) crystal symmetries. Scanning electron micrographs of the samples show uniform distribution of grain and grain boundaries. Dielectric constant increases with the increase in neodymium concentration in the crystal lattice. Degree of diffuse phase transition increases with the increase in Nd3+ concentration in the sample. Nd3+ incorporation into the lead zirconatetitanate (PZT) lattice enhances the spreading factor. Interaction between neighbouring dipoles decreases with the increase of Nd3+ in PZT lattice. The conduction mechanism of the sample can be attributed to the overlapping large polar tunnelling. Second-order dielectric phase transition has been observed at the Curie temperature. The electrical properties of the sample can be explained by considering grain and grain boundaries contributions. All the samples show the poly-dispersive non-Debye type relaxation. [ABSTRACT FROM AUTHOR]

Complex impedance spectroscopic technique has been implemented to study the detailed electrical transport properties of Lead free ferroelectric ceramic solid solutions of (1 − x) Na0.5Bi0.5TiO3-x BaTiO3 (NBT-BT) (0.00 ≤ x ≤ 0.10). The NBT-BT ceramics have been synthesized by sol-gel auto combustion method and sintered via microwave sintering technique. Room temperature X-ray diffraction patterns confirmed the formation of the single phase materials with perovskite structure. The surface morphology of the samples has been studied using field emission scanning electron microscopic (FESEM) technique. The FESEM micrographs confirm that the grain size decreases with increasing BaTiO3 (BT) concentration. Complex impedance, complex electric modulus formalism, and frequency dependent ac conductivity analysis have been used to study the relaxation and conduction mechanism in these materials. The presence of grain- and grain boundary contribution to impedance spectra in NBT-BT ceramics were analyzed using complex impedance plot in association with complex modulus plot. The grain- and grain boundary contributions were discerned in NBT-BT ceramic through least-squares fitting of the experimental data with a suitable equivalent circuit model. Complex impedance and complex electric modulus spectroscopic analysis indicate that the dielectric relaxation in these materials are of non-Debye type. A negative temperature coefficient of resistance (NTCR) behavior of our NBT-BT ceramics was seen from the temperature dependent conductivity studies. We have obtained similar activation energies from the conduction and relaxation process. [ABSTRACT FROM AUTHOR]

The temperature and field dependent capacitive as well as conducting characteristics of double perovskite electronic material (Bi2MnCoO6) have been investigated using dielectric and impedance spectroscopy techniques. The electronic material has been formulated by applying a high temperature solid state reaction based ceramic processing route. The formation of the desired sample material is confirmed with a monoclinic crystal system using room temperature X-ray diffraction analysis. The uniform grain distribution is predicted from the micrograph, and the stoichiometric chemical content of the solid solution is determined from energy dispersive X-ray technique. The acquaintance between micro structural study and frequency–temperature dependent electrical properties of the compound has revealed negative temperature coefficient of resistance behaviour. The prepared compound unveils non-Debye type relaxation. The studied compound presents important dielectric properties which substantiate the material propensity for formulation of electronic devices. [ABSTRACT FROM AUTHOR]

Occult follicular thyroid carcinoma (FTC) presenting as distant metastases is a rare occurrence. However, despite being occult in majority of these cases, primary tumor can be detected on thyroid imaging or during surgery. Here, we present an extremely rare case of an occult FTC with overt skeletal metastases in which primary tumor was discernible only on microscopic examination. [ABSTRACT FROM AUTHOR]

Nearly a century ago it was recognized that radiation absorption by stellar matter controls the internal temperature profiles within stars. Laboratory opacity measurements, however, have never been performed at stellar interior conditions, introducing uncertainties in stellar models. A particular problem arose when refined photosphere spectral analysis led to reductions of 30-50 per cent in the inferred amounts of carbon, nitrogen and oxygen in the Sun. Standard solar models using the revised element abundances disagree with helioseismic observations that determine the internal solar structure using acoustic oscillations. This could be resolved if the true mean opacity for the solar interior matter were roughly 15 per cent higher than predicted, because increased opacity compensates for the decreased element abundances. Iron accounts for a quarter of the total opacity at the solar radiation/convection zone boundary. Here we report measurements of wavelength-resolved iron opacity at electron temperatures of 1.9-2.3 million kelvin and electron densities of (0.7-4.0) × 1022 per cubic centimetre, conditions very similar to those in the solar region that affects the discrepancy the most: the radiation/convection zone boundary. The measured wavelength-dependent opacity is 30-400 per cent higher than predicted. This represents roughly half the change in the mean opacity needed to resolve the solar discrepancy, even though iron is only one of many elements that contribute to opacity. [ABSTRACT FROM AUTHOR]

Plasmonic materials (PMs), featuring large static or dynamic tunability, have significant impact on the optical properties due to their potential for applications in transformation optics, telecommunications, energy, and biomedical areas. Among PMs, the carrier concentration and mobility are two tunable parameters, which control the plasma frequency of a metal. Here, we report on large static and dynamic tunability in wavelengths up to 640 nm in Al-doped ZnO based transparent conducting degenerate semiconductors by controlling both thickness and applied voltages. This extreme tunability is ascribed to an increase in carrier concentration with increasing thickness as well as voltage-induced thermal effects that eventually diminish the carrier concentration and mobility due to complex chemical transformations in the multilayer growth process. These observations could pave the way for optical manipulation of this class of materials for potential transformative applications. [ABSTRACT FROM AUTHOR]

Background:A Population-Based Cancer Registry (PBCR) was set up in Sikkim (a state in the North Eastern India) in 2003. We examined incidence rates by ethnic groups from 2003-2008.Methods:Age-adjusted incidence rates (AARs) per 100 000 person-years were calculated by direct method using the world standard population, and analysed by ethnic group (Bhutia, Rai and other).Result:There were a total of 1148 male and 1063 female cases of cancer between 2003 and 2008 on the Sikkim PBCR. The overall AARs were 89.4 and 99.4 per 100 000 person-years in males and females, respectively. Incidence rates were highest amongst the Bhutia group (AAR=172.4 and 147.4 per 100 000 person-years in males and females, respectively), and the largest difference in rates were observed for stomach cancers with AARs being 12.6 and 4.7 times higher in the Bhutia group compared with other ethnic groups in males and females, respectively.Conclusion:These observations call for further epidemiological investigations and the introduction of screening programmes. [ABSTRACT FROM AUTHOR]

This study focuses on awareness and an experimental demonstration about the use of human urine and wood ash as a fertilizer. This study was conducted in Chanauta, central Nepal, from November 2009 to February 2010. The villagers ( N = 27) were asked about their awareness of eco-sanitation and fertilizer value of urine and ash. All the participants agreed that the use of urine and ash was a good idea. In the experimental study, the fertilizer value of urine+ash was compared with animal manure and no-fertilizer in the cultivation of radish, potato, broadleaf mustard, cauliflower, and cabbage. Different plants cultivated plots received 54-81 kgN/ha with urine+ash or manure fertilizer. The urine+ash fertilizer produced significantly ( p < 0.05) higher broadleaf mustard biomass than obtained from animal manure and without fertilization. Urine+ash-fertilized plots growing radish, potato, cauliflower, and cabbage produced similar or slightly higher yields biomass compared to those achieved with manure fertilization. This might be because of high P, K as well as greater availability of N in applied urine compared to manure. It is concluded that urine+ash fertilizer can be used instead of animal manure; in this study, a dose of 4 L of urine was equal to 1 kg of dry cattle manure and produced a similar or greater yield of vegetable biomass than manure fertilization. To be able to generalize this conclusion, it is important to conduct these kinds of experiments with different seasonal crops and in other parts of the world. [ABSTRACT FROM AUTHOR]

This study is based on a visual inspection and a questionnaire survey about sanitation in central Nepal. A total of 201 people from different groups were asked about their knowledge about eco-toilets, the fertilizer value of human urine and wood ash. Farmers were the least educated and least aware of most of the topics asked. Although the majority of educated people were aware about urine fertilizer, 68% of them were not interested in its use in their home, and 39% of them said that it might be not accepted. The visual inspection revealed that environmental hygiene depends on education. It is concluded that farmers need to receive practical demonstrations about the use of eco-toilets and wood ash to appreciate the direct benefits. It can be assumed that since urine fertilizer is a bonus obtained from eco-toilets, this could encourage even poor people to construct these kinds of facilities. [ABSTRACT FROM AUTHOR]

Different multivariate regression type of estimators for finite population variance under multiphase sampling set up in presence of two auxiliary variables have been suggested. These estimators are compared with estimators using no auxiliary variable or single auxiliary variable theoretically and with the help of numerical examples. [ABSTRACT FROM AUTHOR]

This paper deals with the analysis of active constrained layer damping (ACLD) of laminated thin composite panels using vertically and obliquely reinforced 1–3 piezoelectric composite materials as the material of the constraining layer of the ACLD treatment. A finite element model has been developed for analyzing the ACLD of laminated antisymmetric cross-ply and antisymmetric angle-ply thin composite panels integrated with the patches of such ACLD treatment. Both in-plane and out-of-plane actuations of the constraining layer of the ACLD treatment have been utilized for deriving the finite element model. The analysis revealed that the vertical actuation dominates over the in-plane actuation. Particular emphasis has been placed on investigating the performance of the patches when the orientation angle of the piezoelectric fibers of the constraining layer is varied in the two mutually orthogonal vertical planes. The analysis revealed that the vertically reinforced 1–3 piezoelectric composites which are in general being used for the distributed sensors can be potentially used for the distributed actuators of high performance light-weight smart thin composite panels. [ABSTRACT FROM AUTHOR]

Ultraviolet coronagraph observations of the extended solar corona (defined here as 1.5 to 10 solar radii from Sun-center) have become a powerful tool for obtaining detailed empirical descriptions of coronal holes, streamers, and coronal mass ejections. The empirical models resulting from ultraviolet coronagraph observations provide the constraints needed to test and guide theoretical models aimed at determining the physical processes that control solar wind acceleration, CME heating and acceleration, and solar energetic particle (SEP) acceleration. Measurements to date from sounding rockets, the shuttle deployed Spartan 201 satellite and the Solar and Heliospheric Observatory (SOHO) have utilized high resolution spectroscopy over a very limited instantaneous field of view. New concepts for next generation instrumentation include imaging ultraviolet spectrocoronagraphs and large aperture ultraviolet coronagraph spectrometers. An imaging instrument would be the first to obtain absolute spectral line intensities of the extended corona over a wide field of view. Such images would provide the absolute intensities of spectral lines that can be used to determine densities and outflow velocities of specific coronal ions. Measurements from several charge states of a given element will allow electron temperatures to be determined. These measurements combined with observations of H I Lyα provide absolute chemical abundances (relative to hydrogen) for observed elements. Ultraviolet imaging would be highly complementary to a large-aperture ultraviolet coronagraph spectrometer designed for high spectral resolution observations over a small instantaneous field of view. The images would be used to select targets for more detailed spectroscopic studies with the large aperture UV coronagraph spectrometer and to provide time dependent empirical descriptions of the regions surrounding the narrow instantaneous field of view of the large aperture instrument. Descriptions of both the imaging ultraviolet spectrocoronagraph and the large aperture ultraviolet coronagraph spectrometer are provided. Recommended co-observing instruments are described. [ABSTRACT FROM AUTHOR]

The nanocrystalline fine powders (∼80 nm) of (Ba1− x La x )(Fe2/3W1/3)1− x/4O3, (BLFW) ( x = 0.0, 0.05, 0.10 and 0.15) were synthesized with a combined mechanical activation and conventional high-temperature solid-state reaction methods. Preliminary X-ray structural analysis of pellet samples (prepared from fine powders) showed formation of a single-phase tetragonal system. Detailed studies of dielectric properties (εr and tan δ) exhibit that these parameters are strongly dependent on frequency, temperature and La composition. The La-substitution increases the dielectric constant and decreases the tan δ up to 10% substitutions of La at the Ba-site, and then reversed the variation, and hence this composition is considered as a critical composition. This observation was found valid for structure, microstructures, dielectric constant, electrical conductivity, J– E characteristics and impedance parameters also. Like in other perovskites (PZT, BZT), La substitution plays an important role in tailoring the properties of Ba(Fe2/3W1/3)O3 ceramics. [ABSTRACT FROM AUTHOR]

A ceramic oxide (NaDyTiO4), having layered perovskite structure, has been prepared by a standard high-temperature solid-state reaction technique. X-ray diffraction (XRD) studies have confirmed material formation under reported condition along with the presence of impurity (Na2Dy2Ti3O10) as the minor phase. Complex impedance spectroscopy (CIS) analysis has been carried out to investigate its microstructure and electrical properties as a function of frequency and temperature. CIS analysis has indicated that the electrical behavior of the material sample shows negative temperature coefficient of resistance (NTCR) typical to a semiconductor. Impedance studies have also indicated the presence of temperature dependent relaxation process in the material with a spread of relaxation time. The d.c. conductivity of the material as evaluated from the impedance spectrum has been observed to be ∼10−9 Scm−1 at room temperature (RT). It has been observed to increase as a function of temperature with a maximum of ∼10−5 Scm−1 at 550∘C. The conductivity variation shows a cross over from Mott-type hopping phenomena at lower temperatures to a thermally activated Arrhenius type behavior at high temperature. [ABSTRACT FROM AUTHOR]

A ceramic oxide (NaDyTiO4), having layered perovskite structure, has been prepared by a standard high-temperature solid-state reaction technique. X-ray diffraction (XRD) studies have confirmed material formation under reported condition along with the presence of impurity (Na2Dy2Ti3O10) as the minor phase. Complex impedance spectroscopy (CIS) analysis has been carried out to investigate its microstructure and electrical properties as a function of frequency and temperature. CIS analysis has indicated that the electrical behavior of the material sample shows negative temperature coefficient of resistance (NTCR) typical to a semiconductor. Impedance studies have also indicated the presence of temperature dependent relaxation process in the material with a spread of relaxation time. The d.c. conductivity of the material as evaluated from the impedance spectrum has been observed to be ∼10−9 Scm−1 at room temperature (RT). It has been observed to increase as a function of temperature with a maximum of ∼10−5 Scm−1 at 550∘C. The conductivity variation shows a cross over from Mott-type hopping phenomena at lower temperatures to a thermally activated Arrhenius type behavior at high temperature. [ABSTRACT FROM AUTHOR]

Objective: To explore the influence of night blindness during pregnancy on nighttime work activities of women.Design and Subjects: A community based case-control study was used to compare nighttime activities of night blind (cases) and non-night blind pregnant women (controls) using a 24h recall method to measure work activities (n=116 pairs).Setting: Rural South-Eastern district in the plains of Nepal.Results: Approximately one third of the night blind women reported being 'inactive' the previous night, not participating in any of the inquired work activities, as compared with only 15% of the control group (P < 0.031). The type of work that was significantly affected was the outdoor kind such as fetching water and washing dishes. Logistic regression analysis showed that night blind women were half as likely (odds ratio=0.49, 95% confidence interval=0.25-0.98) to work at night than women without night blindness after controlling for the effects of confounding variables including gestational age, season, and protein energy malnutrition which were significantly associated with nighttime work activity.Conclusions: Night blindness during pregnancy, an indicator of vitamin A deficiency, reduces the number and type of work activities women perform at night, thus impairing women's ability to participate in normal subsistence activities by reducing their 'work day'. [ABSTRACT FROM AUTHOR]

We show the ability to map the phase diagram of a relaxor-ferroelectric system as a function of temperature and composition through local hysteresis curve acquisition, with the voltage spectroscopy data being used as a proxy for the (unknown) microscopic state or thermodynamic parameters of materials. Given the discrete nature of the measurement points, we use Gaussian processes to reconstruct hysteresis loops in temperature and voltage space, and compare the results with the raw data and bulk dielectric spectroscopy measurements. The results indicate that the surface transition temperature is similar for all but one composition with respect to the bulk. Through clustering algorithms, we recreate the main features of the bulk diagram, and provide statistical confidence estimates for the reconstructed phase transition temperatures. We validate the method by using Gaussian processes to predict hysteresis loops for a given temperature for a composition unseen by the algorithm, and compare with measurements. These techniques can be used to map phase diagrams from functional materials in an automated fashion, and provide a method for uncertainty quantification and model selection. Piezoelectrics: Seeing the full picture with machine learning The functional response of piezoelectrics for arbitrary compositions and conditions cannot be fully obtained using local probes. Although the ferroelectric to paraelectric phase transition temperature can be measured, this is only for a limited number of data points. Now, a team led by Rama Vasudevan at Oak Ridge National Laboratory and colleagues in Puerto Rico, the United States, and India demonstrate that machine learning can be used to obtain the full ferroelectric phase diagram, with functional response. From measurements on four samples of a material, they use a machine-learning technique called Gaussian processes to reconstruct piezoelectric properties for continuously varying voltages and temperatures, which with more commonly used approaches accurately predicts ferroelectric phase diagrams. This could be used to generate piezoelectric phase diagrams, highlighting material compositions with optimal properties that can then be targeted by synthesis. [ABSTRACT FROM AUTHOR]

Multiferroic materials have attracted considerable attention as possible candidates for a wide variety of future microelectronic and memory devices, although robust magnetoelectric (ME) coupling between electric and magnetic orders at room temperature still remains difficult to achieve. In order to obtain robust ME coupling at room temperature, we studied the Pb(Fe0.5Nb0.5)O3/Ni0.65Zn0.35Fe2O4/Pb(Fe0.5Nb0.5)O3 (PFN/NZFO/PFN) trilayer structure as a representative FE/FM/FE system. We report the ferroelectric, magnetic and ME properties of PFN/NZFO/PFN trilayer nanoscale heterostructure having dimensions 70/20/70 nm, at room temperature. The presence of only (00l) reflection of PFN and NZFO in the X-ray diffraction (XRD) patterns and electron diffraction patterns in Transmission Electron Microscopy (TEM) confirm the epitaxial growth of multilayer heterostructure. The distribution of the ferroelectric loop area in a wide area has been studied, suggesting that spatial variability of ferroelectric switching behavior is low, and film growth is of high quality. The ferroelectric and magnetic phase transitions of these heterostructures have been found at ~575 K and ~650 K, respectively which are well above room temperature. These nanostructures exhibit low loss tangent, large saturation polarization (Ps ~ 38 µC/cm2) and magnetization (Ms ~ 48 emu/cm3) with strong ME coupling at room temperature revealing them as potential candidates for nanoscale multifunctional and spintronics device applications. [ABSTRACT FROM AUTHOR]

Aphanomyces invadans, the causative agent of epizootic ulcerative syndrome, is one of the most destructive pathogens of freshwater fishes. To date, the disease has been reported from over 160 fish species in 20 countries and notably, this is the first non-salmonid disease that has resulted in major impacts globally. In particular, Indian major carps (IMCs) are highly susceptible to this disease. To increase our knowledge particularly with regards to host immune response against A. invadans infection in a susceptible host, the gene expression profile in head kidney of A. invadans-infected and control rohu, Labeo rohita was investigated using RNA sequencing. Time course analysis of RNA-Seq data revealed 5608 differentially expressed genes, involved among others in Antigen processing and presentation, Leukocyte transendothelial migration, IL-17 signaling, Chemokine signaling, C-type lectin receptor signaling and Toll-like receptor signaling pathways. In the affected pathways, a number of immune genes were found to be downregulated, suggesting an immune evasion strategy of A. invadans in establishing the infection. The information generated in this study offers first systematic mechanistic understanding of the host–pathogen interaction that might underpin the development of new management strategies for this economically devastating fish-pathogenic oomycete A. invadans. [ABSTRACT FROM AUTHOR]

An experimental study has been carried out to improve the bearing capacity of soils by using geotextile. In the present study geojute (gunny bags) is used as geotextile, whereas sand is used as soil media. This research presents the results of laboratory load tests on model square footings supported on reinforced sand beds. A total of 32 load tests are conducted to evaluate the effects of single layer reinforcement placed below square model footings. Parameters of testing programme of the research are the depth of reinforcement, the plan area of reinforcement and the footing size. The test results indicated that the maximum gain in ultimate bearing capacity (UBC) of footings on reinforced soil (by using geojute) is found to be increased by a factor of 3.37 as compared to soil without geojute. Also, the optimum size of reinforcement is found to be 3.5B × 3.5B irrespective of the type of reinforcing materials used. The optimum placement position of geotextile is found to be 0.5B from the base of the footing. At low settlement rates, the study on the values of BCR reveals almost the same results with regard to optimum depth and size of reinforcement mentioned above. It is found that with increase in the settlement rate, BCR increases. Also, the improvement in bearing capacity is found to increase with increase in footing size. [ABSTRACT FROM AUTHOR]