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Cell free supernatants of Bifidobacterium adolescentis and Bifidobacterium longum suppress the tumor growth in colorectal cancer organoid model

Tunneling effect in quantum-dot light-emitting diodes

Charge carrier transportation in semiconductor films is a fundamental but crucial process for the light-emitting diodes. Although there have been many studies on charge transport properties of devices based on traditional inorganic crystals and organic amorphous films, such charge behavior within emerging quantum-dot light-emitting diodes (QLEDs)—which are composed of amorphous nanocrystal films with strong quantum confinement effects—has rarely been discussed. Here, we demonstrate that the tunneling effect really occurs in the hybrid QLEDs with ZnO as the electron-transport layer. By suppressing the thermal effect, a negative differential resistance (NDR) phenomenon is observed by decreasing the working temperature of the QLED low to 150 K. Two types of quantum dots (QDs) with different shell structures (i.e., different tunneling barrier) are used to comparatively examine the tunneling effect. The current density–voltage properties of the QLEDs reveal that the device based on QDs with the sharp core-shell structure (i.e., larger tunneling barrier) exhibits more obvious NDR behavior, which is attributed to the stronger tunneling effect. Our results offer significant insight into the charge dynamics and working mechanism in the QLEDs.

Interpretable machine learning for predicting sepsis risk in emergency triage patients

Theoretical analysis of thermal conductivities of water and heavy water based on thermal resistance network model

Thermal conductivity of liquid water is distinct from that of ordinary liquids due to its complex hydrogen bonding network. In this study, we develop the thermal resistance network model, supplemented by molecular dynamics simulations, to calculate the thermal conductivities of water and heavy water over a temperature range of 275–375 and 300–375 K, respectively. The thermal conductivities of both water and heavy water are computed at various temperatures and pressures, and the results provide agreement with experimental data. Furthermore, it is pointed out that our model offers an interpretation of thermal conductivity based on heat paths among water clusters rather than the traditional vibrational modes.

Integrated singlecell and bulk RNA-seq analysis identifies a prognostic signature related to inflammation in colorectal cancer

The characteristics of line-shaped defects and their impact mechanism on device performance in <i>β</i>-Ga2O3 Schottky barrier diodes

Beta-phase gallium oxide (β-Ga2O3) has attracted increasing attention in the field of power electronic devices due to its ultra-wide bandgap and high Baliga figure-of-merit. However, the premature breakdown deteriorated with the increase in device area, hindering the scale-up of the current rating. In this work, we unveil the formation and characteristics of killer defects responsible for the premature breakdown in an Si-doped (001) β-Ga2O3 epitaxial layer grown by halide vapor phase epitaxy. The killer defects feature a line-shaped morphology along the [010] orientation. Specifically, the high-resolution transmission electron microscopy characterization links the line-shaped defects to underlying voids. These voids are surrounded by amorphous phase regions, and the transition from amorphous phase to crystalline phase results in twins extending along the [010] orientation, which eventually become line-shaped defects on the wafer. Additionally, the defect area exhibits smaller capacitance and lower surface potential compared to the defect-free region. This is attributed to the absence of local ionized donors in the defect area, leading to electric field concentration in this region. This study systematically investigates a killer defect in β-Ga2O3, which contributes to the scale-up process of β-Ga2O3 power devices and advances their application.

Associations between the conicity index and kidney stone disease prevalence and mortality in American adults

Ferromagnetic permalloy/<i>p</i>-type boron-doped diamond Schottky barrier diodes

Ferromagnetic permalloy/p-type boron (B)-doped diamond Schottky barrier diodes (SBDs) were demonstrated. The SBDs showed a clear rectifying behavior with a high on/off ratio of over 109 and an ideality factor close to unity at 300 K. The Schottky barrier height was 2.07 eV at the permalloy/B-doped diamond interface. The permalloy Schottky electrodes did not intermix with B-doped diamond and had almost the same magnetic properties as bulk permalloy.

Investigations on the synthesis and characterization of silver-doped MoO3 thin films for photocatalytic applications

AbstractIn this study, we aimed to enhance the photocatalytic performance of molybdenum oxide (MoO3) thin films by doping with silver (Ag) via a spray pyrolysis technique. The primary objective for silver incorporation was intended to introduce additional energy levels into the band structure of MoO3, improving its efficiency. Structural, optical, and photocatalytic properties were analyzed using X-ray diffraction (XRD) and optical spectroscopy. XRD results confirmed an orthorhombic phase with a (040) preferential orientation for all samples. Optimal crystallinity was observed with 2% Ag doping, yielding an 84 nm crystallite size, while higher doping levels reduced crystallite size. Band gap energy narrowed from 3.07 eV (undoped) to 2.94 eV (2% Ag-doped), indicating electronic structure changes. Impedance spectroscopy revealed superior electrical properties at 4% Ag doping, enhancing charge transport. Photocatalytic performance, assessed via dye degradation, showed significant improvement with silver doping, the degradation rate peaking at 4% Ag. These results demonstrate that silver doping optimizes structural and electronic properties of MoO3 thin films, leading to enhanced photocatalytic activity.

Topological sonic whispering gallery protected by the synthetic Weyl points

The synthetic dimension provides us with a powerful platform to explore the topological properties of matter. In this paper, we choose two physical dimensions (kx and ky) and one geometric structure parameter (the height of the air cavity δ) to construct a synthetic space. The simulation results display that the three couples of Weyl points and Fermi arcs appear in the synthetic space. We find that changing the position of the boundary truncation of a sonic crystal can flexibly regulate the frequency range of valley chiral edge states. Both theoretically and experimentally, we demonstrate the sonic topological valley-locked whispering gallery, in which the valley states propagate along the interfaces between a sonic crystal and a hard wall. In the valley-locked whispering gallery, the sonic waves propagate unidirectionally along the closed channel, with high scattering efficiency and small diffraction.

Surrounding rock control for the roadway driven under the goafs of small collieries and heading for adjacent advancing face

Nitrogen-induced filament confinement strategy for implementing reliable resistive switching performance in a-HfOx memristors

Hafnium oxide (HfOx) films are highly valued as functional layers in nonvolatile resistive switching (RS) memristors due to their scalability, compatibility with CMOS technology, and high dielectric constant. However, the low reliability of HfOx-based memristors is the key factor hindering their widespread practical applications. Herein, amorphous HfOx (a-HfOx) films are used as the switching layers to construct memristors, and the nitrogen treatment strategy is employed to enhance the switching characteristics. All the fabricated Al/a-HfOx/ITO memristors demonstrate bipolar digital RS behaviors, and specifically, the 500 °C-treated a-HfOx device exhibits highly reliable RS performance, including low cycle-to-cycle variability, concentrated distributions and low operating voltages, long-term retention capacity (&amp;gt;104 s), and good cycle endurance (&amp;gt;200 cycles). The mechanisms and physical models for enhanced switching performance are thoroughly elucidated, revealing that the formation of stable oxygen vacancy–dinitrogen complexes confines the conductive filament path and significantly reduces filament randomness during formation and rupture. This work renders an effective material engineering strategy for widening a path toward designing highly reliable nonvolatile data storage devices with striking switching performances.

Core-genome guided novel therapeutic targets identification and chimeric vaccine designing against Rickettsia rickettsii

Improved gate leakage current and breakdown voltage of InAlN/GaN MIS-HEMTs by HfAlOx-based charge-trapping layer dielectric and <i>in situ</i> O3 treatment

In this study, high-performance InAlN/GaN metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs) are fabricated using HfAlOx-based charge-trapping layer dielectric stack combined with in situ O3 treatment. A positive threshold voltage shift (ΔVTH) of 8.9 V is achieved due to the charge-trapping effect. The device also shows a high Ion/Ioff ratio of ∼1010, a low gate leakage current of ∼10−7 mA/mm, and a relatively high BVDS of 400 V. The suppression of gate leakage current results in an ultra-high gate breakdown voltage of 22.5 V, owing to the superior current blocking capability of the O3-based Al2O3/HfO2 blocking layers and the interface improvement between dielectric and InAlN barrier achieved through in situ O3 treatment. The time-dependent dielectric breakdown measurements reveal the quality and reliability of the dielectric layer, predicting a maximum VGS of 9.66 and 9.31 V for a 10-year lifetime at failure rates of 63.2% and 0.10%, respectively. Additionally, x-ray photoelectron spectroscopy, atomic force microscopy, and multi-frequency C–V measurements further verify the effectiveness of the in situ O3 treatment in the optimization of the dielectric/GaN interface. These results demonstrate a practical approach to significantly improve the performance of InAlN/GaN MIS-HEMTs.

Role of P2 X7 receptor during focused ultrasound induced blood brain barrier modulation

Heteroatomic doping induces charge rearrangement to optimize carrier dynamics in 2D halide perovskites

It is well established that a number of techniques, including applied electric fields, interfacial engineering, structural torsion, and doping, can modulate the geometric and electronic structures of materials, thereby enhancing their photoelectronic properties in two-dimensional (2D) halide perovskites. Among these strategies, doping has proven to be an extremely effective approach; however, the precise mechanisms underlying this effect remain elusive. Herein, we systematically investigated how heteroatom doping, specifically using Sn and Bi dopants, influences the excited-state dynamics of 2D (MA)2PbI4 perovskites using ab initio calculations combined with real-time nonadiabatic molecular dynamics simulations. Our results indicate that the doped systems maintain the octahedral configuration characteristics of the parent material. Notably, doping leads to a significant electron–hole separation in real space, corresponding to an extended carrier lifetime of approximately 140–150 ns, compared to just 2.70 ns for pristine (MA)2PbI4 perovskites. This behavior is primarily governed by a low-frequency vibration mode around ∼200 cm−1. These calculations provide important insights into the potential for atomically modulating carrier behaviors to achieve excellent photovoltaic properties.

The homeobox family gene signature predicts the prognosis of osteosarcoma and correlates with immune invasion

Hydrogen-mediated control of magnetic anisotropy and magnetic domain structure in Co/Pd multilayer

This study demonstrates the reversible transition from perpendicular to in-plane magnetic anisotropy in Co/Pd multilayers induced by hydrogenation, using a magneto-optic Kerr microscope. By controlling hydrogen pressure and exposure time, the transition is separated into coercivity and squareness ratio changes, reflecting reduced perpendicular anisotropy and spin reorientation. The Dzyaloshinskii–Moriya interaction is observed through asymmetric magnetic domain expansion, with hydrogenation causing domains to fragment. These results suggest hydrogenation as a method for precise control of magnetic anisotropy and domain structures.

Stability-indicating spectrophotometric quantification of safinamide in the presence of its possible degradation product

AbstractIn recent times, a truly exquisite pharmaceutical marvel has graced the world of medicine, known as Safinamide (SAF). This opulent creation has been specifically tailored to cater to the needs of individuals afflicted with Parkinson’s disease (PD), an esteemed neurological condition renowned for its regal ability to impede motor skills, coordination, and equilibrium. It is highly improbable that degradation products of pharmaceutical components would significantly compromise efficiency and safety of a drug during its shelf life. Pharmaceutical analysis requires a variety of stability tests to be conducted under distinct conditions. As a result, there was an increased need for the development of an analytical methodology capable of reliably separating and quantifying degradants and impurities that might be found in pharmaceuticals. In this study, we have developed two efficient and straightforward spectrophotometric methodologies for the concurrent estimation of SAF and its degradation product (SAF DEG), which is the main acid hydrolysis product. The confirmation of degradation product build-up by the use of several analytical techniques, including infrared spectroscopy (IR), and mass spectrometry (MS) investigations. The present methodologies have been validated for linearity within the concentration range of 5–30 µg/ml for SAF, and 5–15 µg/mL, 2–15 µg/ml for SAF DEG for fourier self-deconvolution (FSD) and dual wavelength (DW) methods, respectively. The originality of these techniques lies in their status as the first stability-indicating spectrophotometric procedures that are both environmentally friendly. Moreover, the process of obtaining pure SAF DEG offers substantial economic benefits by obviating the need to acquire a costly constituent. The use of intelligent techniques was employed to analyze the pharmaceutical dosage form, potentially offering significant advantages to the pharmaceutical industry.

E-mode AlGaN/GaN HEMT with ScAlN/ScN charge trap-coupled ferroelectric gate stacks

A fully epitaxial ferroelectric ScAlN/AlGaN/GaN HEMT coupled with an ultrathin ScN charge trap layer for enhancement-mode operation is demonstrated. The ultrathin ScN acts as an electron reservoir to trap and store the electrons from the 2-dimensional electron gas channel region, transitioning the operation of the GaN high electron mobility transistor from the depletion-mode to the enhancement-mode, while the fully epitaxial nature enables low interface defect density and steep slope operation. The initialization process by applying a positive gate bias to inject carriers to the ScN layer is observed to shift the threshold voltage (Vth) from −1.2 to +1.3 V. The fabricated device also shows a steep subthreshold swing as low as 61 mV/dec and exhibits good stability, providing a promising pathway for power-efficient and multifunctional applications.