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Structural investigation of ultra-low resistance deeply recessed sidewall ohmic contacts for AlGaN/GaN HEMTs based on Ti/Al/Ti-metallization

This study presents a novel approach to forming low-resistance ohmic contacts for AlGaN/GaN HEMTs. The optimized contacts exhibit an outstanding contact resistance of approximately 0.15 Ω·mm. This is achieved by firstly recessing the barrier of the heterostructure to a depth beyond the channel. In this way, the channel region is exposed on the sidewall of the recess. The coverage of the Ti/Al/Ti o

Real-time visualization of smoke for fire safety engineering applications

Visibility in smoke is a key aspect in terms of safe egress in various fire related situations. Due to the hazardous nature of fire induced smoke, it is hard to study human behaviour under such conditions, but recent development within the field of virtual reality (VR) has enabled exposure to many different hazardous conditions while remaining relatively safe. However, to obtain valid results from

Effects of topping and non-topping on growth-regulating hormones of flue-cured tobacco (Nicotiana tabacum L.)—a proteomic analysis

Introduction: Until now, the mechanism underlying the impact of topping on hormone regulation in tobacco plants remains unclear, and most studies investigating the hormone signaling pathways in plants rely on genes or transcriptional pathways. Methods: This study examines the regulatory mechanisms of hormones in the roots and leaves of tobacco plants with and without topping at the protein level.

Simulation of breast lesions based upon fractal Perlin noise

Purpose: Steadily increasing use of computational/virtual phantoms in medical physics has motivated expanding development of new simulation methods and data representations for modelling human anatomy. This has emphasized the need for increased realism, user control, and availability. In breast cancer research, virtual phantoms have gained an important role in evaluating and optimizing imaging sys

Abdominal compression as motion management for stereotactic radiotherapy of ventricular tachycardia

Background and purpose: Stereotactic body radiotherapy (SBRT) has emerged as a promising treatment for patients with ventricular tachycardia (VT) who do not respond to standard treatments. However, the management of respiratory motion during treatment remains a challenge. This study aimed to investigate the effect of abdominal compression (AC) on respiratory induced motion in the heart. Materials

Phase transitions of ionic fluids in nanoporous electrodes

Abstract: In this work, we utilise grand canonical Metropolis Monte Carlo simulations, to establish pore-induced freezing of restricted primitive model fluids. A planar pore model is utilised, with walls that are initially neutral, and either non-conducting or perfectly conducting. The phase of the confined electrolyte (solid/fluid) displays an oscillatory dependence on surface separation, in narr

On the thermal conductivity anisotropy in wurtzite GaN

GaN-based power devices operating at high currents and high voltages are critically affected by the dissipation of Joule heat generated in the active regions. Consequently, knowledge of GaN thermal conductivity is crucial for effective thermal management, needed to ensure optimal device performance and reliability. Here, we present a study on the thermal conductivity of bulk GaN in crystallographi

Probing cellulose–solvent interactions with self-diffusion NMR : Onium hydroxide concentration and co-solvent effects

The molecular self-diffusion coefficients were accessed, for the first time, in solutions of microcrystalline cellulose, dissolved in 30 wt% and 55 wt% aqueous tetrabutylammonium hydroxide, TBAH (aq), and in mixtures of 40 wt% TBAH (aq) with an organic co-solvent, dimethylsulfoxide (DMSO), through pulsed field gradient stimulated echo NMR measurements. A two-state model was applied to estimate α (

Phase II LEAP-004 Study of Lenvatinib Plus Pembrolizumab for Melanoma with Confirmed Progression on a Programmed Cell Death Protein-1 or Programmed Death Ligand 1 Inhibitor Given as Monotherapy or in Combination

PURPOSE Effective treatments are needed for melanoma that progresses on inhibitors of programmed cell death protein-1 (PD-1) or its ligand (PD-L1). We conducted the phase II LEAP-004 study to evaluate the combination of the multikinase inhibitor lenvatinib and the PD-1 inhibitor pembrolizumab in this population (ClinicalTrials.gov identifier: NCT03776136).METHODSEligible patients with unresectable

On the role of internationalization of firm-level corporate governance : The case of audit committees

Research Question/Issue: Motivated by the agency theory and the findings of linguistic studies, we analyze the association between the internationalization of a firm's audit committee and its corporate governance. Research Findings/Insights: Based on data from 2159 publicly traded European firms from 15 countries for the period 2000–2018, we find that firms with foreign directors on their audit co

Deciphering microbiomes dozens of meters under our feet and their edaphoclimatic and spatial drivers

Microbes inhabiting deep soil layers are known to be different from their counterpart in topsoil yet remain under investigation in terms of their structure, function, and how their diversity is shaped. The microbiome of deep soils (>1 m) is expected to be relatively stable and highly independent from climatic conditions. Much less is known, however, on how these microbial communities vary along cl

The microbial biodiversity at the archeological site of Tel Megiddo (Israel)

Introduction: The ancient city of Tel Megiddo in the Jezreel Valley (Israel), which lasted from the Neolithic to the Iron Age, has been continuously excavated since 1903 and is now recognized as a World Heritage Site. The site features multiple ruins in various areas, including temples and stables, alongside modern constructions, and public access is allowed in designated areas. The site has been

Taphonomic experiments reveal authentic molecular signals for fossil melanins and verify preservation of phaeomelanin in fossils

Melanin pigments play a critical role in physiological processes and shaping animal behaviour. Fossil melanin is a unique resource for understanding the functional evolution of melanin but the impact of fossilisation on molecular signatures for eumelanin and, especially, phaeomelanin is not fully understood. Here we present a model for the chemical taphonomy of fossil eumelanin and phaeomelanin ba

Positioning for lumbar puncture in newborn infants

Objectives: This is a protocol for a Cochrane Review (intervention). The objectives are as follows:. To assess the success rate of the lateral decubitus, sitting and prone positions for lumbar puncture in newborn infants.

Assessing Tissue Hydration Dynamics Based on Water/Fat Separated MRI

Background: Optimal fluid status is an important issue in hemodialysis. Clinical evaluation of volume status and different diagnostic tools are used to determine hydration status in these patients. However, there is still no accurate method for this assessment. Purpose: To propose and evaluate relative lean water signal (LWSrel) as a water–fat MRI-based tissue hydration measurement. Study Type: Pr

Long-Term Effect of TBX4 Germline Mutation on Pulmonary Clinico-Histopathologic Phenotype

Tbx4 protein, expressed in mesenchyme of the developing lung, contributes to airway branching and distal lung growth. An association between pediatric onset of pulmonary arterial hypertension (PAH) and genetic variations coding for the T-box transcription factor 4 gene (TBX4) has been increasingly recognized. Tbx4-related PAH onset has a bimodal age distribution, including severe to lethal PAH in

Deep H i Mapping of Stephan's Quintet and Its Neighborhood

We carried out deep mapping observations of the atomic hydrogen (H i) 21 cm line emission in a field centered on the famous galaxy group Stephan's Quintet (SQ), using the Five-hundred-meter Aperture Spherical Telescope (FAST) equipped with a 19-beam receiver. The final data cube reaches an H i column density sensitivity of 5σ = 2.1 × 1017 cm-2 per 20 km s-1 channel with an angular resolution of 4.

Post-traumatic stress disorder and drug use disorder : examination of aetiological models in a Swedish population-based cohort

Background: There are two primary phenotypic models of comorbidity between post-traumatic stress disorder (PTSD) and drug use disorder (DUD), i.e. self-medication (PTSD precedes and causes DUD) and susceptibility (DUD precedes and causes PTSD). We sought to clarify the longitudinal relationship between PTSD and DUD, while examining sex differences. Method: We used approximately 23 years of longitu

Fear and posting in Nepal : countering spectacles of fear through everyday social media practices

This article sheds light upon the cultural politics of fear in post-war Nepal by narrowing in on the Nepal banda–a recurring political spectacle in which the organizers seek to shut down Nepalese society through violent means–tracing both how it shapes and is appropriated in (offline and online) everyday life. In doing so I demonstrate how the online tactics that people employ to navigate the Nepa

Three-pion scattering : From the chiral Lagrangian to the lattice

In recent years, detailed studies of three-pion systems have become possible in lattice QCD. This has in turn led to interest in 3-to-3 scattering of pions in the chiral perturbation theory framework. In addition to being an interesting study of multi-meson dynamics in its own right, it provides a valuable handle on finite-volume effects and the pion mass dependence, thus complementing the lattice