Synthesis of a large area ReS2 thin film by CVD for in-depth investigation of resistive switching: effects of metal electrodes, channel width and noise behaviour.

The anisotropic crystal structure and layer independent electrical and optical properties of ReS2 make it unique among other two-dimensional materials (2DMs), emphasizing a special need for its synthesis. This work discusses the synthesis and in-depth characterization of a 1 × 1 cm2 large and few layered ReS2 film. Vibrational modes and excitonic peaks observed from the Raman and photoluminescence (PL) spectra corroborated the formation of a ReS2 film with a 1.26 eV bandgap. High resolution transmission electron microscopy (HRTEM) images and selected area electron diffraction (SAED) patterns inferred the polycrystalline nature of the film, while cross-sectional field emission scanning electron microscopy (FESEM) indicated planar growth with ∼10 nm thickness. The chemical composition of the film analysed through X-ray photoelectron spectroscopy (XPS) indicated the formation of a ReS2 film with a Re : S atomic ratio of 1 : 1.75, indicating a small amount of non-stoichiometric RexSy. Following the basic characterization studies, the ReS2 film was tested for resistive switching (RS) device application in which the effects of different metal electrodes (Pt/Au and Ag/Au) and different channel widths (200, 100, and 50 µm) were studied. The highest memory window equal to 108 was obtained for the Ag/Au electrode while Pt/Au showed a memory window of 102. RS for the former was ascribed to the formation of a conducting filament (CF) because of the migration of Ag+ ions, while defect mediated charge carrier transport led to switching in the Pt/Au electrode. Furthermore, the RHRS/RLRS ratio achieved in this work (108) is also of the highest magnitude reported thus far. Furthermore, a comparison of devices with Ag/Au electrodes but with different channel widths (50, 100 and 200 µm) gave insightful results on the existence of multiple resistance states, device endurance and retention. An inverse relationship between the retention time and the device's channel width was observed, where the device with a 50 µm channel width showed a retention time of 48 hours, and the one with a 200 µm width showed stability only up to 3000 s. Furthermore, low frequency noise measurements were performed to understand the effect of defects in the low resistance state (LRS) and the high resistance state (HRS). The HRS exhibited Lorentzian noise behaviour while the LRS exhibited Lorentzian only at low current bias which converged to 1/f noise at higher current bias.

Contemporary management of prostatic abscess: Our experience.

Introduction: Prostatic abscess is a serious urological problem that needs immediate attention due to its high morbidity and mortality in absence of appropriate treatment. The objective of our study is to evaluate the efficacy and safety of various modalities of management of prostatic abscess: medical management (MM), transrectal ultrasound-guided aspiration (TRUS-GA), and transurethral deroofing (TU-DR. Methods: This retrospective study was done in a tertiary care center after taking approval from the institutional review board. Conservative management was done by oral or parenteral medications. Transrectal ultrasound GAs were performed under local anesthesia with an 18-gauge two-part needle. Collapse of cavity was seen in "real time" on TRUS. TU-DR of the prostate was done by 26 French continuous irrigation monopolar resectoscopes. The aspirated pus was sent for microbiological investigation. Results: TRUS-guided aspiration was performed in 20 patients, TU-DR in five patients, and conservative management in 15 patients. The mean volume of abscess aspirated by TRUS guidance was 13 cc (range 8-50 cc) with single-time aspiration in 85% of cases. Re-aspiration was done in 3 patients. The mean volume of abscess was 33.2 cc (range: 25-40 cc) in TU-DR group and 1.2 cc (range 0.5-2.0 cc) in the MM group. The predominant organism isolated was Escherichia coli (48%). Clinical improvement was seen in 97.5% of cases. Conclusion: We suggest TRUS-GA for symptomatic patients with abscess size more than 2 cc and TU-DR if TRUS-GA fails or is contraindicated.

Role ofin-situhydrogen plasma treatment on gate bias stability and performance of a-IGZO thin-film transistors.

This work investigates the effect of anin situhydrogen plasma treatment on gate bias stability and performance of amorphous InGaZnO thin-film transistors (TFTs) deposited by using atmospheric-pressure PECVD. The H2plasma-treateda-IGZO channel has shown significant improvement in bias stress induced instability with a minuscule threshold voltage shift (ΔVth) of 0.31 and -0.17 V under positive gate bias stress (PBS) and negative gate bias stress (NBS), respectively. With the aid of the energy band diagram, the proposed work demonstrates the formation of negative species O2-and positive species H2O+in the backchannel under PBS and NBS in addition to ionized oxygen vacancy (Vo) defects ata-IGZO/ZrO2interfaces are the reason for gate bias instability which could be effectively suppressed within situH2plasma treatment. From the experimental result, it is observed that the electrical performance such as field-effect mobility (µFE), on-off current ratio (Ion/Ioff), and subthreshold swing improved significantly byin situH2plasma treatment with passivation of interface trap density and bulk trap defects.

Clinical Impact of Co-medication of Levetiracetam and Clobazam with Proton Pump Inhibitors: A Drug Interaction Study.

BACKGROUND: Clobazam (CLBZ) metabolized primarily by Cytochrome P-450 isoenzyme CYP3A4 than with CYP2C19, Whereas Levetiracetam (LEV) is metabolized by hydrolysis of the acetamide group. Few CYP enzymes are inhibited by Proton Pump Inhibitors (PPIs) Pantoprazole, Esomeprazole, and Rabeprazole in different extents that could affect drug concentrations in blood. The aim of the present study was to evaluate the effect of these PPIs on the plasma concentrations of LEV and CLBZ. METHODS: Blood samples from 542 patients were included out of which 343 were male and 199 were female patients and were categorized as control and test. Plasma samples analyzed using an HPLC-UV method. Plasma concentrations were measured and compared to those treated and those not treated with PPIs. One way ANOVA and games Howell post hoc test used by SPSS 20 software. RESULTS: CLBZ concentrations were significantly 10 folds higher in patients treated with Pantoprazole (P=0.000) and 07 folds higher in patients treated with Esmoprazole and Rabeprazole (P=0.00). Whereas plasma concentration of LEV control group has no statistical and significant difference when compared to pantoprazole (P=0.546) and with rabeprazole and esomeprazole was P=0.999. CONCLUSION: The effect of comedication with PPIs on the plasma concentration of clobazam is more pronounced for pantoprazole to a greater extent when compared to esomeprazole and rabeprazole. When pantoprazole is used in combination with clobazam, dose reduction of clobazam should be considered, or significance of PPIs is seen to avoid adverse effects.

Diagnostic dilemma of a rare, giant retroperitoneal schwannoma: a case report and review of literature.

Schwannoma is a benign tumour of peripheral nerve sheath. It usually arises from head, neck, and trunk. Retroperitoneal schwannoma is a rare entity, accounting for only 0.3-3% of total schwannomas. Majority of retroperitoneal schwannomas reported in literature have a diameter of 5 to 15 cm. Preoperative diagnosis is difficult due to low frequency, nonspecific clinical course, and nonspecific imaging features. Histology usually provides definitive diagnosis. Schwannomas are solitary, well-circumscribed, and noninvasive, so complete surgical excision provides good result. We report a case of a 23-year-old male, who presented with progressive abdominal distension and intermittent episodes of intestinal obstruction. CECT was suggestive of huge solid-cystic mass in abdominopelvic region. Image guided percutaneous aspiration revealed around 1 litre of frank pus and FNAC was suggestive of abscess. Exploratory laparotomy revealed a large 32 × 28 × 26 cm mass with solid and cystic components containing 1 litre of pus. Histological features of tumour were suggestive of benign schwannoma and immunohistochemistry for S-100 was positive. Postoperative recovery was uneventful. We report this case of a retroperitoneal schwannoma because of giant size, rare location, unusual presentation, and diagnostic dilemma.

Remote forest refugia for Fijian wildlife.

On Pacific islands non-native rats and mongooses threaten many native species. In Fiji we compared visitation rates of rats and mongooses at bait stations and measured biomass of leaf-litter invertebrates to assess the relative predation pressure from these species in forest areas at different distances from the forest edge. Forest areas over 5 km from the forest edge had significantly fewer baits encountered by rats or mongooses than did natural forest areas nearer agricultural and urban habitats. Remote forest areas may function as a last refuge for island species threatened by predation from non-native rats and mongooses. The biomass of leaf-litter invertebrates in remote forest areas was higher indicating a refuge effect for some taxa targeted by rats and mongooses. Protection of the few remaining large blocks of natural forests on Pacific islands may be the most cost-effective approach for conserving many island endemics threatened by rats and mongooses. Logging roads can compromise this refuge effect by acting as dispersal routes for rats into natural forests.