Role of GO and r-GO in resistance switching behavior of bilayer TiO2 based RRAM

Graphene-based resistance random access memory devices (RRAMs) have shown promise as a suitable replacement for flash memories, owing to their fast switching speed, low programming voltage, better scalability and great reliability. Furthermore, recent research works have shown bi-layer RRAM devices exhibiting better performance along the same parameters, where titania is one of the most commonly used materials. In the present work, we have studied the resistance switching behavior in a bi-layer RRAM device structure of TiO2 with graphene oxide (GO) and reduced graphene oxide (rGO). Switching mechanism in these devices has been investigated by detailed experimental characterization in conjunction with a finite element modeling (FEM) simulation. A dual conical conductive filament has been used in the present work, based on the modeling of the electroforming process carried out by FEM. It has been demonstrated that for the GO/TiO2 based hybrid RRAM device structure, GO acts as an active filament formation layer, whereas in the rGO/TiO2 bi-layer structure, rGO acts as a mere electrode

Comparative efficacy of inhaled ciclesonide, budesonide, and fluticasone in mild to moderately persistent bronchial asthma

Background: Bronchodilators and glucocorticoids have been proven to be very effective and safe in asthma treatment, which recommend the use of steroids and β2-agonist (long or short acting) as the first line of treatment in of asthma. This study was aimed to compare the efficacy of three different inhaled corticosteroids ciclesonide, budesonide, and fluticasone in bronchial asthma.Methods: A total of 30 patients with mild to moderately persistent bronchial asthma was selected as per the NAEPP classification in the expert panel report (EPR) update 2002, NHLBL USA 2003. They were randomly divided into 3 groups of 10 patients each, and they were given 3 different steroid inhalers (ciclesonide or budesonide or fluticasone). Baseline and post-therapy spirometry were performed on day 1 and after 2 months and 6 months of treatment. Data were analyzed using SPSS software.Results: It was observed that most of the cases (43.3%) were between 26 and 35 years of age with female preponderance (56.6%). Significant symptomatic improvement was observed in all 3 groups. The percentage of improvement in mean peak expiratory flow rate was 17%, 18%, and 18% in ciclesonide, budesonide, and fluticasone group, respectively. The percentage improvement of forced expiratory volume in 1 second (FEV1)/forced vital capacity after bronchodilatation was 18%, 18%, and 19% in ciclesonide, budesonide, and fluticasone group, respectively. The improvement in mean FEV1% predicted was 20%, 19%, and 21% in three groups, respectively.Conclusion: Steroid therapy along with β2-agonists showed a significant improvement in symptoms. There was no difference among the three different types of steroids

Compositional fluctuations mediated by excess of tellurium in bismuth antimony telluride nanocomposite yields high thermoelectric performance

A high thermoelectric figure of merit (ZT) in state-of-the-art bismuth antimony telluride (BST) composites was attained by an excess tellurium-assisted liquid-phase compaction approach. Herein, we report a maximum ZT of approximate to 1.4 at 500 K attained for BST bulk nanocomposites fabricated by spark plasma sintering of colloidally synthesized (Bi,Sb)(2)Te-3 platelets and Te-rich rods. The Terich nanodomains and antimony precipitation during sintering result in compositional fluctuations and atomic ordering within the BST-Te eutectic microstructure, which provides additional phonon scattering and hole contributions. The electrical transport measurement and theoretical calculations corroborate the altered free carrier density via lattice defects and atomic ordering under Te-rich conditions, resulting in a higher power factor. Microstructural studies suggest that reduction in lattice thermal conductivity is due to composite interfaces and defects in the closely packed (Bi,Sb)(2)Te-3 matrix with unevenly distributed Sband Te-rich nanodomains. This work provides an unconventional chemical synthesis route with large scalability for developing high-performance chalcogenide-based bulk nanocomposites for thermoelectric applications.- We thank the members of the Nanochemistry Research Group (http://nanochemgroup.org) at INL for insightful discussions and support. This work was supported by the Portuguese national funding agency for science, research, and technology (FCT) under the UT-BORN-PT project (UTAP-EXPL/CTE/0050/2017), strategic project UID/FIS/04650/2020, Project SATRAP (POCI-01-0145-FEDER-028108) and Advanced Computing Project CPCA/A2/4513/2020 for access to MACC-BOB HPC resources. B.A.K. acknowledges funding of this work by the Robert A. Welch Foundation (grant no. F1464). N.S.C. and T.M. acknowledge SERB, India (project no. SPO/SERB/MET/2018547) for financial support

Effect of Total Dissolved Solids and Temperature on Bacteriophage Therapy against Luminous vibriosis in Shrimp

Bacteriophage therapy is an efficient, eco-friendly, and scientifically demonstrable solution to antibiotic resistance in bacteria. Environmental factors have a profound influence on the growth and activity of phages. We evaluated the influence of two important parameters of the aquatic environment on phage activity, i.e., total dissolved solids (TDS) and temperature. Evaluated levels of TDS were 11.25, 22.63, and 38.43 mg/ml; studied temperatures were 20, 30, and 37ºC. Levels were chosen from the ranges of values encountered during larvae rearing in a hatchery. Of seve

Ten Steps for NPH Management: Advancements in Diagnosis and Treatment of Adult Hydrocephalus

Objectives The authors of the present study intend to describe a straightforward protocol for normal pressure hydrocephalus diagnosis and management, with the employment of a multidisciplinary team approach effort

Enhanced Thermoelectric Performance in the SrTi_0.85Nb_0.15O₃ Oxide Nanocomposite with Fe₂O₃‑Functionalized Graphene

Doped SrTiO3 is considered one of the potential thermoelectric (TE) candidates but its TE figure of merit, ZT needs to be improved for practical application of electricity generation from high-grade waste-heat. In the present work, enhanced TE performance has been realized for SrTi0.85Nb0.15O3 (STN) perovskite adopting the strategy of composite formation with Fe2O3-functionalized graphene (FGR). We have achieved a maximum electrical conductivity of 1.4 × 105 S m–1 for 1 wt % FGR added to STN, which is around 1185% larger than that of pristine STN. The presence of FGR in the STN matrix acts as a mobility booster of electrons, overcoming the effect of Anderson localization of electrons, which impedes the electron transport in STN. This is evident from the order of magnitude increase in weighted mobility of STN after FGR addition. Furthermore, the incorporation of FGR causes about a 34% decrease in the lattice thermal conductivity. The Debye–Callaway model demonstrates that the phonon–phonon Umklapp scattering is primarily responsible for reduced thermal conductivity. The presence of FGR sheets along the grain boundaries of STN, Fe2O3 nanoparticles, and lattice imperfections gives rise to the glass-like temperature-independent phonon mean-free-path, especially above Debye temperature. The maximum ZT ∼ 0.57 has been obtained at 947 K for the 1 wt % FGR sample, which is around 420% higher than that of pristine STN. Furthermore, we have fabricated a prototype of a four-legged n-type TE module, demonstrating one of the highest power outputs of 18 mW among reported oxide thermoelectrics

Malignant nodular hidradenoma of scalp

Malignant nodular hidradenoma (MNH) is a rare tumor of sweat gland known by many names in the literature. Scalp is a known and yet uncommon site of occurrence. We describe two patients with scalp MNH with brain parenchymal invasion. Both tumors recurred in spite of total excision and radiotherapy