Classification of drug molecules for oxidative stress signalling pathway

In humans, oxidative stress is involved in the development of diabetes, cancer, hypertension, Alzheimers’ disease, and heart failure. One of the mechanisms in the cellular defence against oxidative stress is the activation of the Nrf2‐antioxidant response element (ARE) signalling pathway. Computation of activity, efficacy, and potency score of ARE signalling pathway and to propose a multi‐level prediction scheme for the same is the main aim of the study as it contributes in a big amount to the improvement of oxidative stress in humans. Applying the process of knowledge discovery from data, required knowledge is gathered and then machine learning techniques are applied to propose a multi‐level scheme. The validation of the proposed scheme is done using the K‐fold cross‐validation method and an accuracy of 90% is achieved for prediction of activity score for ARE molecules which determine their power to refine oxidative stress.Inspec keywords: cancer, cellular biophysics, biochemistry, drugs, molecular biophysics, proteins, learning (artificial intelligence), medical computingOther keywords: oxidative stress, Nrf2‐antioxidant response element signalling pathway, ARE signalling pathway, diabetes, cancer, hypertension, Alzheimers’ disease, heart failure, machine learning techniques, K‐fold cross‐validation method, ARE molecules     

Nanometer MOSFET Variation in Minimum Energy Subthreshold Circuits

Minimum energy operation for digital circuits typically requires scaling the power supply below the device threshold voltage. Advanced technologies offer improved integration, performance, and active-energy efficiency for minimum energy sub-V_t circuits, but are plagued by increased variation and reduced I_ON/I_OFF ratios, which degrade the fundamental device characteristics critical to circuit operation by several orders of magnitude. This paper investigates those characteristics and presents design methodologies and circuit topologies to manage their severe degradation. The issues specific to both general logic and dense static random access memories are analyzed, and solutions that address their distinct design metrics are presented.     

Thermally stimulated current and electrical conduction in metal (1)-ethyl cellulose-metal (1)/(2) systems

Depolarization current characteristics of solution grown pure ethyl cellulose (EC) films of about 20μm thickness have been studied as a function of electrode materials at constant poling field (5 × 10⁴ V/cm) and poling temperature 40°C. Thermally stimulated current (TSC) thermograms of EC consists of two well resolved peaks (located at 60°C and 140°C) for Al-Al system, which are attributed to the deorientation of strongly attached ethoxy groups of glycosidal units and diffusion of space charges either at electrodes or due to their thermal release at higher temperatures from the defect levels. For dissimilar electrode combinations (Al-Ag/Cu/Au/Sn/Pb), an indication of peak of lower magnitude at around (50–70°C) alongwith a higher temperature peak (140–155°C), have been observed. TSC parameters are found to change with the choice of electrode material. The dependence of dark current at 40°C in metal-ethyl cellulose-metal systems on applied voltage in the range (2·0–5·0) × 10⁴V/cm has also been studied. The results of current-voltage measurement on EC have been interpreted to show that the Schottky-Richardson mechanism is the controlling transport mechanism. Zero field current density extrapolated fromI-E ^1/2 plots are found to vary with metal work function.     

Factorization and the Nehari theorem in time-varying systems

The Nehari Theorem and related results on operator interpolation play an important role in modern system theory. These results are embedded in a function-theoretic conceptual framework and therefore restricted to LTI systems. We give a state space oriented extension of the Nehari Theorem to a time-varying system-theoretic setting. In that setting the theorem addresses the issue of measuring the distance between a noncausal bounded I/O operator and the family of causal I/O operators in stable linear systems. The analysis is based on the recent time-domain LQ optimization approach to robust control. The discussion includes a geometrical analysis of stable and antistable invariant subspaces, a short study of certain types of co-prime factorizations of I/O operators in time-varying systems, and a parametrization of all suboptimal solutions.The research was supported in part by the National Science Foundation under Grant ECS 9108927 and by the U.S. Army Research Office under Contract DAALO3 92 G 0015.The research was supported by NSERC, Canada.     

Kinetics of hydrogenation of D-glucose to sorbitol

The kinetics of the heterogeneous reaction between hydrogen and aqueous solutions of D -glucose to produce sorbitol were studied in a high pressure Parr reactor. Raney-Ni was used as catalyst. The reaction between hydrogen and D -glucose was found to be very slow. In the agitated slurry reactor the diffusional aspects were completely eliminated and the reaction followed homogeneous kinetics. It was found to be first order with respect to both hydrogen and D -glucose. The values of the pseudo-first-order rate constants were found to be 1.5 × 10^?4 and 6.4 × 10^?4s^?1 at 398 and 435 K, respectively. The activation energy was found to be 64.8 kJ mol^?1.     

Influence of different polyesters and their molecular weight on the textural and electrooptical behavior of polymer‐dispersed liquid crystals

The textural and electrooptical behavior of a nematic liquid crystal (LC) dispersed in a flexible and rigid polyester was studied. The dispersion of LC in the polymer matrix and light transmission through the polymer‐dispersed liquid crystal (PDLC) is governed by the nature of the polymer, its molecular weight, and the applied voltage. It was observed that the transmission of light and the dispersion of LC maximizes their respective values at the minimum molecular weight irrespective of the nature of the polymer and at the maximum voltage. The reason is the predominance of chain alignment over entanglement at the minimum molecular weight. As molecular weight increases, the transmission of light as well as the dispersion of LC in the polymer may increase or decrease depending on the predominance of chain entanglement or chain alignment. The alignment of LC droplets in the direction of the applied voltage is increased by an increase in the applied voltage, causing enhancement of the light transmission. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 284–289, 2003     

Renal osmotic stress-induced cotransporter: expression in the newborn, adult and post-ischemic rat kidney

The renal osmotic stress-induced cotransporter (ROSIT), a new putative member of a family of organic solute transporters, is highly expressed in the kidney. Our in situ hybridization data now reveal that large amounts of ROSIT mRNA can be found in the S3 segment of the proximal tubule. In the developing kidney, ROSIT mRNA is expressed after the S-shaped body stage. Because the S3 segment is the major site of damage in the post-ischemic kidney, we evaluated alterations in ROSIT mRNA expression after ischemic acute tubular necrosis. Renal osmotic stress-induced cotransporter mRNA levels were already decreased eight hours post-ischemia. At seven days post-ischemia, ROSIT mRNA reappeared in a mosaic pattern in the regenerating S3 segment, being fully expressed three weeks after the insult except for focal areas. The exact localization of this putative osmolyte transporter in the kidney, together with that of other known osmolyte transporter will contribute to a better understanding of the mechanism of medullary osmolyte accumulation and its vectorial transport.     

Elimination of bipolar induced drain breakdown and singletransistor latch in submicron PD SOI MOSFET

For the first time, we report the combined application of a SiGe source and a delta-doped p⁺ region in a PD SOI MOSFET to minimize the impact of floating body effect on both the drain breakdown voltage and the single transistor latch. Our results demonstrate that the proposed SOI structure exhibits as large as 200% improvement in the breakdown voltage and is completely immune to single transistor latch when compared to the conventional SOI MOSFET thus improving the reliability of these structures in VLSI applications     

Effect of iron content on permeability and power loss characteristics of Li0.35Cd0.3Fe2.35O4 and Li0.35Zn0.3Fe2.35O4

Substituted lithium ferrites having the chemical formula, Li_0.35Cd_0.3Fe_2.35O₄ and Li_0.35Zn_0.3Fe_2.35O₄, with different iron (metal) contents (2, 4, 6, 8 and 10) in wt% have been prepared by solid-state technique. Complex permeability and power loss of all samples have been measured by network analyser in the frequency range of 50–5000 kHz. Magnetic properties like saturation magnetization, coercivity, retentivity have been measured by vibrating sample magnetometer (VSM). The permeability of cadmium doped lithium ferrites exhibited higher values than zinc doped lithium ferrites. The power loss of cadmium doped lithium ferrites is lesser as compared to zinc doped lithium ferrites in the frequency range of 50–5000 kHz and at flux density of 10 mT. The behaviour of power loss with flux density has been found near about same for both series. Magnetic and power loss behaviour of the samples suggest that a small amount of Fe content can improve the properties of ferrite samples for microwave devices.     

CaCO3/TiO2 Nanoparticles Based Dye Sensitized Solar Cell

In this communication,the synthesis and structural,morphological,optical,and photo-electrochemical properties of TiO_2 and CaCO_3/TiO_2 nanoparticles as well as their applications in dye sensitized solar cells(DSSCs),have been reported.In an X-ray diffraction pattern of CaCO_3/TiO_2 nanoparticles,the peak at 29.41°of CaCO_3 has been detected,demonstrating its coating on the surface of TiO_2,which is further verified using high resolution-transmission electron microscopy,energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy.The strong quenching in photoluminescence emission,in the case of CaCO_3/TiO_2nanoparticles,has been attributed to the decrease in recombination rate of photo-generated electron—hole pairs.In the case of UV—visible reflectance spectra,the absorption edge for CaCO_3/TiO_2 nanoparticles has slightly been found to be blue-shifted as compared to bare TiO_2 nanoparticles,which corresponds to an increase in energy band gap of the former.The dye desorption studies reveal that CaCO_3/TiO_2 electrodes adsorbed more dye than the bare TiO_2 electrode.CaCO_3/TiO_2 based DSSC show improved photoelectrochemical properties compared to the bare TiO_2 based DSSC as CaCO_3 coating on TiO_2 forms an energy barrier,and,consequently suppressing the charge recombination,and,thus,improving the overall energy conversion efficiency(η) from 0.46%to 1.44%under the illumination of simulated light of 100 mW/cm~2.