Nanoscale tunnel field effect transistor based on a complex oxide lateral heterostructure

We demonstrate a tunnel field effect transistor based on a lateral heterostructure patterned from an $\mathrm{LaAlO_3/SrTiO_3}$ electron gas. Charge is injected by tunneling from the $\mathrm{LaAlO_3}$/$\mathrm{SrTiO_3}$ contacts and the current through a narrow channel of insulating $\mathrm{SrTiO_3}$ is controlled via an electrostatic side gate. Drain-source I/V-curves have been measured at low and elevated temperatures. The transistor shows strong electric-field and temperature-dependent behaviour with a steep sub-threshold slope %of up to as small as $10\:\mathrm{mV/decade}$ and a transconductance as high as $g_m\approx 22 \: \mathrm{\mu A/V}$. A fully consistent transport model for the drain-source tunneling reproduces the measured steep sub-threshold slope.Comment: 20 pages, 6 figures, Supplementary material: 4 pages, 2 figure

Understanding and treating ejaculatory dysfunction in men with Diabetes mellitus

INTRODUCTION: Diabetes mellitus (DM) is a rapidly rising metabolic disorder with important systemic complications. Global figures have demonstrated the prevalence of DM has almost quadrupled from 108 million in 1980 to 422 million in 2014, with a current prevalence of over 525 million. Of the male sexual dysfunction resulting from DM, significant focus is afforded to erectile dysfunction (ED). Nevertheless, ejaculatory dysfunction (EjD) constitutes important sexual sequelae in diabetic men, with up to 35-50% of men with DM suffering from EjD. Despite this, aspects of its pathophysiology and treatment are less well understood than ED. The main disorders of ejaculation include premature ejaculation (PE), delayed ejaculation (DE), anejaculation (AE) and retrograde ejaculation (RE). BACKGROUND: Although EjD in DM can have complex multifactorial aetiology, understanding the pathophysiological mechanisms caused by DM has facilitated the development of therapies in the management of EjD. Most of our understanding of its pathophysiology is derived from diabetic animal models, however observational studies in humans have also provided useful information in elucidating important associative factors potentially contributing to EjD in diabetic men. These have provided the potential for more tailored treatment regimens in patients depending on the ejaculatory disorder, other co-existing sequelae of DM, specific metabolic factors as well as the need for fertility treatment. However, the evidence for treatment of EjD, especially DE and RE, is based on low-level evidence comprising small sample-size series and retrospective or cross-sectional studies. Whilst promising findings from large randomised controlled trials (RCTs) have provided strong evidence for the licensed treatment of PE, similar robust studies are needed to accurately elucidate factors predicting EjD in DM, as well as for the development of pharmacotherapies for DE and RE. Similarly, more contemporary robust data is required for fertility outcomes in these patients, including methods of sperm retrieval and assisted reproductive techniques (ART) in RE. This article is protected by copyright. All rights reserved

Solubility and Permeability Studies of Aceclofenac in Different Oils

Purpose: To measure the extent of solubility of the lipophilic drug,   aceclofenac, in 13 oils as well as its in vitro permeability from these oils in order to develop optimized topical microemulsion and  microemulsion-based gel for improved bioavailability.Methods: UV spectrophotometeric method was used at the wavelength of 276 nm to measure the dissolved quantity of aceclofenac in each of the oils (almond oil, oleic acid, castor oil, paraffin oil, cinnamon oil, clove oil, canola oil, sesame oil, isopropyl myristate (ipm), sunflower oil, corn oil, coconuts oil and eucalyptus oil) at 25 °C. The in-vitro permeability of aceclofenac in each of these oils was determined at 32 ± 0.5 °C using Franz diffusion cell with phosphate buffer (pH 7.4) as medium with 0.45ì cellulose acetate membrane. The solubility and permeability of aceclofenac were compared with the hydroalcoholic solution of aceclofenac.Results: The highest solubility values of 9.153 and 8.560 mg/ml for  aceclofenac were obtained with almond oil and oleic acid, respectively (p < 0.05). However the solubility and permeability of aceclofenac in hydro-alcoholic solution were 150.65 mg/ml and 14.91± 0.05 ìg/cm2/h,  respectively. Aceclofenac also showed higher permeability values (1.45± 0.04 and 1.21 ± 0.06) in almond oil and oleic acid, respectively, than in the other oils (p < 0.05).Conclusion: These findings show that almond oil and oleic acid are  promising vehicles for aceclofenac as its enhanced solubility and  permeability in these vehicles are suggestive of improved bioavailability.Keywords: Aceclofenac, Almond oil, Solubility; Permeability, Oleic acid, Bioavailability

Analysis of Simvastatin using a Simple and Fast High Performance Liquid Chromatography-Ultra Violet Method: Development, Validation and Application in Solubility Studies

Purpose: To develop and validate an accurate, rapid and reproducible reversed-phase high performance liquid chromatography (RP-HPLC) analytical method for the lipid lowering drug, simvastatin, and to apply the developed method to study the solubility of the drug in various oils andsurfactants.Methods: Isocratic RP-HPLC system with a UV-vis detector, and a column with dimensions 4.6 mm x 150 mm and 5ì particle size, was employed. The mobile phase consisted of methanol and 0.01M KH2PO4 phosphate buffer (80:20) at pH 5.5 adjusted with phosphoric acid (2M) and pumped at a flow rate of 1 ml/min. Validation parameters, viz, limit of detection (LOD), limit of quantification (LOQ) linearity, accuracy, precision, and sensitivity, were established. Solubility study was performed in various oils and surfactants at 25°C and the developed HPLC method was applied to analyze all samples.Results: The developed HPLC method showed good linearity (R2 = 0.9958 ± 0.0040. The intra- and inter-day % accuracy was more than 98 %. LOQ and LOQ were 0.160 and 0.484 ìg/ml respectively. Simvastatin showed the highest solubility in sesame oil (15 mg/ml) and in Tween 80 (11 mg/ml) at 25oC.Conclusion: An accurate, rapid and robust HPLC-UV method has been developed, validated and applied successfully to determine the solubility of simvastatin in oils.Keywords: Simvastatin, Validation, Solubility, Sesame oil, Tween 80

Protein binding affinity prediction using support vector regression and interfecial features

In understanding biology at the molecular level, analysis of protein interactions and protein binding affinity is a challenge. It is an important problem in computational and structural biology. Experimental measurement of binding affinity in the wet-lab is expensive and time consuming. Therefore, machine learning approaches are widely used to predict protein interactions and binding affinities by learning from specific properties of existing complexes. In this work, we propose an innovative computational model to predict binding affinities and interaction based on sequence, structural and interface features of the interacting proteins that are robust to binding associated conformational changes. We modeled the prediction of binding affinity as classification and regression problem with least-squared and support vector regression models using structure and sequence features of proteins. Specifically, we have used the number and composition of interacting residues at protein complexes interface as features and sequence features. We evaluated the performance of our prediction models using Affinity Benchmark Dataset version 2.0 which contains a diverse set of both bound and unbound protein complex structures with known binding affinities. We evaluated our regression performance results with root mean square error (RMSE) as well as Spearman and Pearson's correlation coefficients using a leave-one-out cross-validation protocol. We evaluate classification results with AUC-ROC and AUC-PR Our results show that Support Vector Regression performs significantly better than other models with a Spearman Correlation coefficient of 0.58, Pearson Correlation score of 0.55 and RMSE of 2.41 using 3-mer and sequence feature. It is interesting to note that simple features based on 3-mer features and the properties of the interface of a protein complex are predictive of its binding affinity. These features, together with support vector regression achieve higher accuracy than existing sequence based methods

Case Study: The Surgical Management of Angiokeratoma Resulting from Radiotherapy for Penile Cancer

Angiokeratoma is a rare, benign skin lesion and a recognised complication of radiation therapy. Here we describe a case of extensive angiokeratoma of the groin and external genitalia resulting from external beam radiation to that area in a patient with penile carcinoma. Furthermore, we outline the management of this problem by surgical reconstruction

Splitting It Up: The spduration Split-Population Duration Regression Package for Time-Varying Covariates

We present an implementation of split-population duration regression in the spduration (Beger et al., 2017) package for R that allows for time-varying covariates. The statistical model accounts for units that are immune to a certain outcome and are not part of the duration process the researcher is primarily interested in. We provide insights for when immune units exist, that can significantly increase the predictive performance compared to standard duration models. The package includes estimation and several post-estimation methods for split-populationWeibull and log-logistic models. We provide an empirical application to data on military coups

Paraganglioma of the Spermatic Cord: Case Report and Review of the Literature

Paragangliomas rarely involve the genitourinary tract. We present a case of a paraganglioma arising from the spermatic cord and review the literature on the topic