Graphics processing unit-accelerated Monte Carlo simulation of polarized light in complex three-dimensional media

Significance: Monte Carlo (MC) methods have been applied for studying interactions between polarized light and biological tissues, but most existing MC codes supporting polarization modeling can only simulate homogeneous or multi-layered domains, resulting in approximations when handling realistic tissue structures. Aim: Over the past decade, the speed of MC simulations has seen dramatic improvement with massively-parallel computing techniques. Developing hardware-accelerated MC simulation algorithms that can accurately model polarized light inside 3-D heterogeneous tissues can greatly expand the utility of polarization in biophotonics applications. Approach: Here we report a highly efficient polarized MC algorithm capable of modeling arbitrarily complex media defined over a voxelated domain. Each voxel of the domain can be associated with spherical scatters of various radii and densities. The Stokes vector of each simulated photon packet is updated through photon propagation, creating spatially resolved polarization measurements over the detectors or domain surface. Results: We have implemented this algorithm in our widely disseminated MC simulator, Monte Carlo eXtreme (MCX). It is validated by comparing with a reference CPU-based simulator in both homogeneous and layered domains, showing excellent agreement and a 931-fold speedup. Conclusion: The polarization-enabled MCX (pMCX) offers biophotonics community an efficient tool to explore polarized light in bio-tissues, and is freely available at http://mcx.space/.

Nephrotic syndrome induced by cetuximab in a patient with metastatic colorectal cancer

Introduction Cetuximab, an anti-EGFR monoclonal antibody, often cause skin toxicity, most commonly acneiform rash. We present a rare case of glomerulonephritis associated with cetuximab therapy. Case Report A 58-year-old male patient recently completed cetuximab-based chemotherapy for metastatic colorectal adenocarcinoma. He presented with acute renal failure, anasarca edema and nephrotic proteinuria. The amount of protein in the 24-h urine test was over 15.6 grams. Management & Outcome The patient showed a dramatic improvement in renal function shortly after terminated of cetuximab therapy without immunosuppressive therapy. Discussion Therefore, drugs targeting epidermal growth factor receptor (EGFR) monoclonal antibody were thought to trigger nephrotic syndrome by causing glomerular damage. As a result, physicians using EGFR monoclonal inhibitors should be very careful about renal functions and proteinuria in patients.

COVID-19 and Stress: A Young Male Presenting with Central Cyanosis, Dark Urine, Oliguria, Jaundice and Anemia due to Methemoglobinemia as a result of Suicidal Naphthalene Mothball Poisoning Recovered with Exchange Transfusion

A young man presented with abdominal pain and vomiting after eating Naphthalene Mothball. He had dyspnea, central cyanosis (SaO2 on air was 67% on air), marked pallor, deep jaundice and dehydration. His urine color was black; and, his plasma in clotted blood sample was brownish. He was treated as methemoglobinemia due to suicidal Naphthalene Mothball poisoning with fluid and electrolyte replacement, ascorbic acid, N-acetylcystine and exchange transfusion twice with four units of whole blood. Dramatic improvement in central cyanosis immediately following exchange transfusion. Psychiatric consultation and counselling were done; he admitted the main reason for committing suicide was socioeconomic stress due to COVID-19.

Hybrid CTC-Attention Network-Based End-to-End Speech Recognition System for Korean Language

In this study, an automatic end-to-end speech recognition system based on hybrid CTC-attention network for Korean language is proposed. Deep neural network/hidden Markov model (DNN/HMM)-based speech recognition system has driven dramatic improvement in this area. However, it is difficult for non-experts to develop speech recognition for new applications. End-to-end approaches have simplified speech recognition system into a single-network architecture. These approaches can develop speech recognition system that does not require expert knowledge. In this paper, we propose hybrid CTC-attention network as end-to-end speech recognition model for Korean language. This model effectively utilizes a CTC objective function during attention model training. This approach improves the performance in terms of speech recognition accuracy as well as training speed. In most languages, end-to-end speech recognition uses characters as output labels. However, for Korean, character-based end-to-end speech recognition is not an efficient approach because Korean language has 11,172 possible numbers of characters. The number is relatively large compared to other languages. For example, English has 26 characters, and Japanese has 50 characters. To address this problem, we utilize Korean 49 graphemes as output labels. Experimental result shows 10.02% character error rate (CER) when 740 hours of Korean training data are used.

Optimisation of processing conditions during CVD growth of 2D WS2 films from a chloride precursor

Monolayer tungsten disulphide (WS2) is a direct band gap semiconductor which holds promise for a wide range of optoelectronic applications. The large-area growth of WS2 has previously been successfully achieved using a W(CO)6 precursor, however, this is flammable and a potent source of carbon monoxide (CO) upon decomposition. To address this issue, we have developed a process for the wafer-scale growth of monolayer WS2 from a tungsten hexachloride (WCl6) precursor in a commercial cold-wall CVD reactor. In comparison to W(CO)6, WCl6 is less toxic and less reactive and so lends itself better to the large-scale CVD growth of 2D layers. We demonstrate that a post-growth H2S anneal can lead to a dramatic improvement in the optical quality of our films as confirmed by photoluminescence (PL) and Raman measurements. Optimised films exhibit PL exciton emission peaks with full width at half maximum of 51 ± 2 meV, comparable to other state-of-the-art methods. We demonstrate that our WS2 films can be readily transferred from the sapphire growth substrate to a Si/SiO2 target substrate with no detectable degradation in quality using a polystyrene support layer. Our approach represents a promising step towards the industrial-scale fabrication of p-n junctions, photodetectors and transistors based on monolayer WS2.

Implementation of a PID Type Sliding-Mode Controller Design Based on Fractional Order Calculus for Industrial Process System

This paper is devoted to designing a fractional order Proportional Integral Derivative (PID) type sliding mode control method (FO-PIDSMC) for a non-linear liquid level coupled tank process system. By considering the individual advantages of the FO calculus and PID type SMC method, this proposed FO-PIDSMC technique is designed to integrate the FO calculus method with PID type SMC scheme to obtain an accurate and robust liquid level tracking in terms of the predefined reference trajectory. The real-time experimental results of the proposed controller suggest a dramatic improvement over the traditional process system controller methods in both trajectory tracking and required control action.

Case Report: A Case of Hailey–Hailey Disease Mimicking Condyloma Acuminatum and a Novel Splice-Site Mutation of ATP2C1 Gene

Hailey–Hailey disease (HHD) is a rare autosomal-dominant blistering disorder characterized by recurrent vesicular and erosive lesions at intertriginous sites. We described a 24-year-old male who presented with multiple bright red verrucous papules in his mons pubis, bilateral groins, scrotum, perineum, and crissum, clinically resembling condyloma acuminatum. The histopathology showed extensive acantholysis with the characteristic appearance of a dilapidated brick-wall. The mutation analysis revealed a novel splice-site mutation in the ATP2C1 gene. The patient was definitely diagnosed with HHD. The antibacterial treatments resulted in a dramatic improvement. Our findings help to broaden the understanding of clinical manifestations of HHD and improve the clinical diagnosis and treatment of this disease.

A case of immune-complex mediated glomerulonephritis associated with pembrolizumab

Introduction: Immune checkpoint inhibitors (ICI) are changing the way we treat cancer. However, these novel agents have various systemic adverse events that may preclude its use and cause poor patient outcomes. ICI-associated acute kidney injury is an emerging complication of this treatment. While tubulointerstitial disease is the most common pathologic finding of patients with ICI-associated AKI, there is sparse data in medical literature describing its association with glomerular disease. Case report: Here, we present a patient with metastatic lung adenocarcinoma who developed acute kidney injury and significant proteinuria after receiving pembrolizumab. The kidney biopsy revealed a membranoproliferative and diffuse segmental endocapillary proliferative pattern of glomerular injury. Management and outcome: Pembrolizumab was then held and high-dose prednisone was initiated, resulting in a rapid and dramatic improvement in kidney function and proteinuria. Discussion: We highlight a report of a patient diagnosed with immune-complex mediated glomerulonephritis associated with the use of pembrolizumab, who was successfully treated with drug withdrawal and corticosteroids.

Resolution of Severe Neurologic Signs Following Intravenous Lipid Emulsion Therapy in a Young Dog With a Portosystemic Shunt: Case Report

A 5-month-old male intact Great Pyrenees was presented for an acute onset of severe neurologic signs (stupor, absent menace, intermittent head turn to the left). The patient's history included possible naproxen ingestion with a maximum ingested dose of 59 mg/kg, exceeding the reported dose of >50 mg/kg known to cause neurologic signs. Blood sampling for baseline bloodwork was performed, and intravenous lipid emulsion (ILE) was subsequently administered, for treatment of the suspected toxicosis. Due to severe and life-threatening neurologic signs, other methods of decontamination were contraindicated and unlikely to be effective; extracorporeal therapy was also unavailable. Complete resolution of neurologic signs occurred 30 min after completion of ILE therapy. At this time, the owners found the missing naproxen tablets after returning home and the bloodwork results returned revealing findings consistent with hepatic encephalopathy. The fasted blood ammonia concentration immediately prior to ILE administration was 702.1 μg/dL (reference interval, RI: 24–36 μg/dL) and decreased to 194.1 μg/dL 24 h later. In the first 24 h, the patient also received three doses of lactulose, N-acetylcysteine, and intravenous fluids. The patient was subsequently diagnosed with a single, large intrahepatic portosystemic shunt via computed tomography and underwent an endovascular coil embolization procedure. Given the rapid and dramatic improvement in severe neurologic signs after ILE therapy alone, it is strongly suspected that this treatment resulted in improvement of hepatic encephalopathy.

Cyclic vomiting syndrome responding to amisulpride – A case report

Cyclic vomiting syndrome (CVS) is an uncommon functional condition defined by recurring episodic stereotyped vomiting with a sudden start and an unknown origin. CVS can be triggered by a variety of conditions, and the course and management are often determined by the triggering factors. We present the case of a 13-year-old female youngster who complained of frequent bouts of vomiting that coincided with the onset of menses. We started her on oral amisulpride 50 mg a few days before each menstrual period. As a result of the treatment, in the following menstrual cycle, she had a dramatic improvement in her symptoms.