Effect of Alpha-Type external input on annihilation of self-sustained activity in a two population neural field model

In the present work, we investigate the annihilation of persistent localized activity states (bumps) in a Wilson-Cowan type two-population neural field model in response to $\alpha$ -type spatio-temporal external input. These activity states serves as working memory in the prefrontal cortex. The impact of different parameters involved in the external input on annihilation of these persistent activity states is investigated in detail. The $\alpha$ -type temporal function in the external input is closer to natural phenomenon as observed in Roth et. al . ( Nature Neuroscience , vol. 19 (2016), 229–307). Two types of eraser mechanism are used in this work to annihilate the spatially symmetric solutions. Initially, if there is an activity in the network, inhibitory external input with no excitatory part and over excitation with no inhibition in the external input can kill the activity. Our results show that the annihilation of persistent activity states using $\alpha$ -type temporal function in the external input is more roubust and more efficient as compare to triangular one as used by Yousaf et al. ( Neural networks. , vol. 46 (2013), pp. 75–90). It is also found that the relative inhibition time constant plays a crucial role in annihilation of the activity. Runge-Kutta fourth order method has been employed for numerical simulations of this work.publishedVersio

Mechanical Behavior of Normal Concrete Reinforced with Kantharo Suter Fiber

Physical characteristics of concrete can be enhanced by addition of different materials in various proportions. Fibrous substances, such as, steel, synthetic, glass, and natural fibers not only increase the structural and tensile strength but also cohesion of concrete by overcoming micro cracks and deficiencies in concrete. In this study, the effect of Kantharo suter fibers (animal hair) on compressive, flexural and split tensile strength, and workability of plain concrete was determined. For that, experiments were conducted on concrete cubes, beams and cylinders by adding different proportions of Kantharo suter fibers from 0.125 to 1.0 percentage by weight of cement. In each proportion of Kantharo suter fibers, three cubes, three cylinders and one beam were casted and cured for 28 days. The acquired results were compared with the plain cement concrete specimens. It was discovered from the results that 0.375 percentages of Kantharo suter fibers in normal concrete was optimum by weight of cement. The strength parameters and slump of concrete showed better results than control mixes even without using any admixture in the specimens. This study could also be enhanced using combinations of different fibers and other admixtures

Interactive effects of vanadium and phosphorus on their uptake, growth and heat shock proteins in chickpea genotypes under hydroponic conditions

The present study was carried out to examine the interaction of vanadium and phosphorus and changes in heat shock genes to optimize the growth of chickpea genotypes. Two sets of hydroponic experiments were carried out using vanadium and phosphorus with five-level central composite design. Five levels of vanadium (0-1180 mu M) and phosphorus (0-100011 mu M) were used to evaluate their interactive effects. Plants fresh biomass and uptake of vanadium and phosphorus were influenced by vanadium and phosphorus application. Enhanced fresh biomass was most likely a result of increased phosphorus uptake by chickpea genotypes. Addition of vanadium induced toxic effects while, higher concentration of phosphorus alleviated its toxic effects. The obtained results also indicated that lower vanadium concentration promoted phosphorus absorption however; higher concentration of vanadium inhibited the phosphorus uptake. The morphological changes in leaves indicated that the cells were deformed and reduced in size when treated with higher vanadium levels with fixed phosphorus while, there was little deformation and reduction in cells size were observed when plants were treated with higher levels of phosphorus with fixed vanadium. Whereas, the proportion of deformation of cells were higher in Balkasar as compared to C-44 genotype. The results also showed that at elevated vanadium with fixed phosphorus, Hsp70 was expressed only in C-44 while, not in Balkasar however, Hsp90 and GAPDH showed non-significant results. (C) 2016 Elsevier B.V. All rights reserved

Frequency of common factors leading to nutritional rickets among children under 2 years of age

Introduction:  Ricket is a disorder of developing bones. It is secondary to the mineralization defect at growth plate matrix. In industrialization countries, the elimination of nutritional rickets or vitamin D deficiency has been done by prophylactic means. In under developed countries of Asia,it remains major health problem. There are a lot of factors which take part in synthesis of vitamin D. These factors include sun exposure, pigmentation of skin and pollution etc.  Objective: To determine the frequency of common factors leading to nutritional rickets among the children under 2 years of age. Results: Total 147 children under age of 2 years suffering with rickets were included in the study.1.5:1 was male to female ratio.13.74 months + 6.4SD was the average age of the patients with range 3-24 months .120(81.6%) sufferers have been observed with the lack of vitamin D supplementation followed by low maternal education 111 (75.5%). Conclusion: Vitamin D supplementation deficiency is main factor for children suffering from nutritional rickets.It is considered in the management of such patients

The Kingsguard OS-level mitigation against cache side-channel attacks using runtime detection

International audienceMost of the mitigation techniques against access-driven cache side-channel attacks (CSCAs) are not very effective. This is mainly because most mitigation techniques usually protect against any given specific vulnerability of the system and do not take a system-wide approach. Moreover, they either completely remove or greatly reduce the performance benefits. Therefore, to find a security vs performance trade-off, we argue in favor of need-based protection in this paper, which will allow the operating system to apply mitigation only after successful detection of CSCAs. Thus, detection can serve as a first line of defense against such attacks. In this work, we propose a novel OS-level runtime detection-based mitigation mechanism, called the Kingsguard, against CSCAs in general-purpose operating systems. The proposed mechanism enhances the security and privacy capabilities of Linux as a proof of concept, and it can be widely used in commodity systems without any hardware modifications. We provide experimental validation by mitigating three state-of-the-art CSCAs on two different cryptosystems running under Linux. We have also provided results by analyzing the effect of the combination of multiple attacks running concurrently under variable system noise. Our results show that the Kingsguard can detect and mitigate known CSCAs with an accuracy of more than 99% and 95%, respectively

Bioherbicidal potential of some allelopathic agroforestry and fruit plant species against Lepidium sativum

Herbicide resistance and environmental pollution are the risks associated with chemical control of weeds. Allelopathic plant extracts may be exploited for weed management as an alternative to commercial herbicides. Before development of allelochemical-based eco-friendly herbicides, bioherbicidal potential of plants need to be evaluated. Present study was conducted to evaluate phytotoxic allelopathic impact of leaf extract from eight agroforestry and fruit plant species against Lepidium sativum. The results showed that all plant species delayed germination and inhibited root length, shoot length and seedling dry weight of Lepidium sativum. Four plant species such as Moringa oleifera, Mangifera indica, Albizia procera and Delonix regia were most phytotoxic with Lepidium sativum root growth inhibition of ≥85% as compared with control and seedling persistence index <30% of control. Phenolic contents were maximum in Mangifera indica (137 mg g-1 leaf dry weight) followed by Delonix regia (130 mg g-1 leaf dry weight). The results suggest that phytotoxic action of leaf extract of plant species may be due to presence of phenolic allelochemicals that may be exploited further either directly for weed management or development of bioherbicides

ZnO/MgZnO heterostructure membrane with type II band alignment for ceramic fuel cells

Semiconductor membrane fuel cells are a new promising R&amp;D for solid oxide fuel cells and proton ceramic fuel cells. There is a challenge of the electronic short circuit issue by using semiconductor to replace conventional electrolyte membrane. In this work, type II band alignment of the semiconductor heterostructure based on Mg-doped ZnO and ZnO can, on one hand, block electrons passing through the junction, and on the other hand, trigger the ionic properties of membrane to boost the fuel cell performance. The Mg doping into ZnO creates more oxygen vacancies at the surface of ZnO, leading to enhanced ionic transport, and meaningful fuel cell performance of 673 mW/cm2; while the Mg-doped ZnO/ZnO heterostructure fuel cell has delivered 997 mW/cm2 and OCV 1.04 V at 520 oC. It is worth highlighting that the constructed heterostructure interface, especially the band bending and constituted build-in electric field, plays a pivotal role in enhancing the ionic transport and suppressing the electron passing through the internal device. First principal calculations using density functional theory confirmed the doping of Mg and the formation of heterostructure with ZnO to help for enhancing charge carriers and separations. This work suggests that the constructed type II band alignment or the semiconductor heterostructure is useful for developing advanced fuel cells

A-site deficient semiconductor electrolyte Sr1−xCoxFeO3−δ for low-temperature (450-550 °C) solid oxide fuel cells

Funding Information: This work was supported by Southeast University (SEU) PROJET no. 3203002003A1 and the National Natural Science Foundation of China (NSFC) under grant no. 51772080 and 11604088. Jiangsu Provincial Innovation and Entrepreneurship Talent Program Project No. JSSCRC2021491. Industry-University-Research Cooperation Project of Jiangsu Province in China, Grant No. BY2021057. Dr Asghar thanks the Hubei Talent 100 program and Academy of Finland (Grant No. 13329016, 13322738) for their financial support. Publisher Copyright: © 2022 The Royal Society of Chemistry.Fast ionic conduction at low operating temperatures is a key factor for the high electrochemical performance of solid oxide fuel cells (SOFCs). Here an A-site deficient semiconductor electrolyte Sr1−xCoxFeO3−δ is proposed for low-temperature solid oxide fuel cells (LT-SOFCs). A fuel cell with a structure of Ni/NCAL-Sr0.7Co0.3FeO3−δ-NCAL/Ni reached a promising performance of 771 mW cm−2 at 550 °C. Moreover, appropriate doping of cobalt at the A-site resulted in enhanced charge carrier transportation yielding an ionic conductivity of >0.1 S cm−1 at 550 °C. A high OCV of 1.05 V confirmed that neither short-circuiting nor power loss occurred during the operation of the prepared SOFC device. A modified composition of Sr0.5Co0.5FeO3−δ and Sr0.3Co0.7FeO3−δ also reached good fuel cell performance of 542 and 345 mW cm−2, respectively. The energy bandgap analysis confirmed optimal cobalt doping into the A-site of the prepared perovskite structure improved the charge transportation effect. Moreover, XPS spectra showed how the Co-doping into the A-site enhanced O-vacancies, which improve the transport of oxide ions. The present work shows that Sr0.7Co0.3FeO3−δ is a promising electrolyte for LT-SOFCs. Its performance can be boosted with Co-doping to tune the energy band structure.Peer reviewe

Improved Ionic Transport Using a Novel Semiconductor Co_0.6Mn_0.4Fe_0.4Al_1.6O₄ and Its Heterostructure with Zinc Oxide for Electrolyte Membrane in LT-CFCs

Improving the ionic conductivity and slow oxygen reduction electro-catalytic activity of reactions occurring at low operating temperature would do wonders for the widespread use of low-operating temperature ceramic fuel cells (LT-CFCs; 450–550 °C). In this work, we present a novel semiconductor heterostructure composite made of a spinel-like structure of Co0.6Mn0.4Fe0.4Al1.6O4 (CMFA) and ZnO, which functions as an effective electrolyte membrane for solid oxide fuel cells. For enhanced fuel cell performance at sub-optimal temperatures, the CMFA–ZnO heterostructure composite was developed. We have shown that a button-sized SOFC fueled by H2 and ambient air can provide 835 mW/cm2 of power and 2216 mA/cm2 of current at 550 °C, possibly functioning down to 450 °C. In addition, the oxygen vacancy formation energy and activation energy of the CMFA–ZnO heterostructure composite is lower than those of the individual CMFA and ZnO, facilitating ion transit. The improved ionic conduction of the CMFA–ZnO heterostructure composite was investigated using several transmission and spectroscopic measures, including X-ray diffraction, photoelectron, and UV–visible spectroscopy, and density functional theory (DFT) calculations. These findings suggest that the heterostructure approach is practical for LT-SOFCs

Enabling high ionic conductivity in semiconductor electrolyte membrane by surface engineering and band alignment for LT-CFCs

Wide bandgap semiconductor perovskite SrTiO3 (STO) has attracted extensive attention due to its higher kinetics of electrons (electronic conductivity). However, rare studies have been performed to tune the STO semiconductor towards ionic conduction, which could make it a promising candidate for an electrolyte in ceramic fuel cells (CFCs). Herein, we have designed a semiconductor perovskite Co/Fe–SrTiO3 as an electrolyte membrane to tune its semiconducting property to the ionic conduction via surface-enriched O-vacancies. The surface doping of Co/Fe into SrTiO3 resulted in lowering the Fermi level, leading to the space charge region and local electric field on the surficial region, which can enhance the ionic conduction (proton conduction) at the surface. The designed electrolyte exhibited a high ionic conductivity of 0.19 S/cm and the fuel cell employing it delivered a maximum power density of 1016 mW/cm2 at 520 °C. Moreover, the theoretical calculation was performed to support the experimental results, like disorder in lattice and oxygen vacancy formation energy. The surface doping of Co/Fe facilitated the enriched surface channels for quick ion transportation with lower activation energy. The presented methodology of surface doping has proven to be suitable for designing advanced materials for wide bandgap semiconductors with high ionic conductivity to develop next-generation CFCs.Peer reviewe