Operando Observation of Electrically Triggered Phase Transition in Thin CuS Crystal.

CuS has been identified as a functional material of memristors with multilevel resistance switching. However, as the migration of Cu ions under the electric field is tangled with defect evolution and phase transition, the electroresistance mechanism of CuS remains largely unclear. Here, the electrically triggered phase transition was studied by transmission electron microscopy.

Etoposide targets 2A protease to inhibit enterovirus 71 replication.

Enterovirus 71 (EV71) is a major pathogen that causes hand, foot, and mouth disease (HFMD) in infants and children. Notably, no clinically approved drugs specifically target EV71. The EV71 2A protease (2A), a cysteine protease produced by the virus, is essential for the virus' replication and has a significant impact on the functioning of host cells.

In Situ STEM Observation of Phase Transition Triggered by Mo Migration in MoTe.

The heterostructure of transition metal dichalcogenides (TMDs), such as one-dimensional (1D) nanowires embedded in two-dimensional (2D) nanosheets, has drawn much research attention due to its unique electronic, spintronic, magnetic, and catalytic properties. The general approach for preparing such a heterostructure is through electron beam lithography or annealing on the 2D template, triggering direct formation of the 1D component within the 2D matrix. However, the thermodynamic mechanism behind the transition from 2D to 1D is still not well clarified.

An In Vitro Study of 355-nm Laser Ablation of Atherosclerotic Lesions Model.

A study of 355 nm laser with high pulse energy across various types of atherosclerotic lesion models is presented. The 355 nm laser pulses (10 ns) are delivered via a single fiber (600 μm diameter), and the ablation of calcified tissue, lipid tissue, and thrombus-like tissue are studied under varied laser fluence (40-70 mJ/mm) and repetition rate (5-30 Hz). The contact and noncontact ablation processes of chicken tibia samples (calcified tissue) are compared at 60 mJ/mm and 30 Hz, and the size of ablation particles is in the range of 0.

Two-Dimensional-Like Phonons in Three-Dimensional-Structured Rhombohedral GeSe-Based Compounds with Excellent Thermoelectric Performance.

The coupling of charge and phonon transport in solids is a long-standing issue for thermoelectric performance enhancement. Herein, two new narrow-gap semiconductors with the same chemical formula of GeSeTe (GST) are rationally designed and synthesized: one with a layered hexagonal structure (H-GST) and the other with a non-layered rhombohedral structure (R-GST). Thanks to the three-dimensional (3D) network structure, R-GST possesses a significantly larger weighted mobility than H-GST.

Rational Design of Cu Vacancies and Antisite Defects for Boosting the Thermoelectric Properties of CuGaTe-Based Compounds.

CuGaTe-based compounds show great promise in the application for high-temperature thermoelectric power generation; however, its wide bandgap feature poses a great challenge for enhancing thermoelectric performance via structural defects modulation and doping the system. Herein, it is discovered that the presence of Ga antisite defects in the CuGaTe compound promotes the formation of Cu vacancies, and vice versa, which tends to form the charge-neutral structure defects combination with one Ga antisite defect and two Cu vacancies. The accumulation of Cu vacancies in the structure of the (CuTe)(GaTe) compounds evolves into twins and stacking faults.

High Ductility and Excellent Thermoelectric Performance in Te-Stabilized Cubic AgTeS Solid Solutions.

The stabilization at low temperatures of the AgS cubic phase could afford the design of high-performance thermoelectric materials with excellent mechanical behavior, enabling them to withstand prolonged vibrations and thermal stress. In this work, we show that the AgTeS solid solutions, with Te content within the optimal range 0.20 ≤ ≤ 0.

Unraveling electronic origins for boosting thermoelectric performance of p-type (Bi,Sb)Te.

P-type BiSbTe compounds are crucial for thermoelectric applications at room temperature, with BiSbTe demonstrating superior performance, attributed to its maximum density-of-states effective mass (*). However, the underlying electronic origin remains obscure, impeding further performance optimization. Herein, we synthesized high-quality BiSbTe (00 ) films and performed comprehensive angle-resolved photoemission spectroscopy (ARPES) measurements and band structure calculations to shed light on the electronic structures.

Topological Electronic Transition Contributing to Improved Thermoelectric Performance in p-Type MgSb Bi Solid Solutions.

Topological electronic transition is the very promising strategy for achieving high band degeneracy (N) and for optimizing thermoelectric performance. Herein, this work verifies in p-type MgSb Bi that topological electronic transition could be the key mechanism responsible for elevating the N of valence band edge from 1 to 6, leading to much improved thermoelectric performance. Through comprehensive spectroscopy characterizations and theoretical calculations of electronic structures, the topological electronic transition from trivial semiconductor is unambiguously demonstrated to topological semimetal of MgSb Bi with increasing the Bi content, due to the strong spin-orbit coupling of Bi and the band inversion.

Electrically Triggered Domain Wall Movement in CuSe Semiconductor.

The ion-conductive α-CuSe is found to possess antipolar dipoles, and the movement of the domain boundary under the applied voltage causes change of resistance, showing promising application in memristors. However, due to the complex ordering of Cu ions in the α-CuSe, there are multiple types of domain wall structure. Here, we show that two typical domain walls in α-CuSe can be formed, by controlling the voltage during phase transition from high-temperature cubic β-CuSe to α-CuSe.

Excellent Room Temperature Thermoelectric Performance in MgSb-Based Alloys via Multi-Functional Doping of Nb.

MgSb-based alloys are attracting increasing attention due to the excellent room temperature thermoelectric properties. However, due to the presence and easy segregation of charged Mg vacancies, the carrier mobility in MgSb-based alloys is always severely compromised that significantly restricts the room temperature performance. General vacancy compensation strategies cannot synergistically optimize the complicated MgSb structures involving both interior and boundary scattering.

Optimization of Mechanical and Thermoelectric Properties of SnTe-Based Semiconductors by Mn Alloying Modulated Precipitation Evolution.

Multiscale defects engineering offers a promising strategy for synergistically enhancing the thermoelectric and mechanical properties of thermoelectric semiconductors. However, the specific impact of individual defects, in particular precipitation, on mechanical properties remains ambiguous. In this work, the mechanical and thermoelectric properties of Sn MnTe (x = 0-0.

Nature of Thermal Hysteresis of Thermoelectric Properties in AgTeS Compounds.

AgTeS usually undergo various phase structures upon heating or cooling processes; however, the correlation between the heat treatment, the phase structure, and the physical properties is still a controversy. Herein, three different phases are realized for AgTeS (0.35 ≤ ≤ 0.

Strain-Induced Defect Evolution for the Construction of Porous CuSe with Enhanced Thermoelectric Performance.

Superionic CuSe, with disordered and even liquid-like Cu ions, has been extensively studied as a high efficiency thermoelectric material. However, the relationship between lattice stability and microstructure evolution in CuSe under strain, which is crucial for its application, has seldom been explored in previous research. In this study, we investigate the impacts of hydrostatic compression strain on the microstructural evolution and, consequently, its implications for thermoelectric performance.

Exploring the Epitaxial Growth Kinetics and Anomalous Hall Effect in Magnetic Topological Insulator MnBiTe Films.

The discovery of MnBiTe-based intrinsic magnetic topological insulators has fueled tremendous interest in condensed matter physics, owing to their potential as an ideal platform for exploring the quantum anomalous Hall effect and other magnetism-topology interactions. However, the fabrication of single-phase MnBiTe films remains a common challenge in the research field. Herein, we present an effective and simple approach for fabricating high-quality, near-stoichiometric MnBiTe films by directly matching the growth rates of intermediate BiTe and MnTe.

Synergetic Enhancement of Strength-Ductility and Thermoelectric Properties of Ag Te by Domain Boundaries.

Simultaneously improving the mechanical and thermoelectric (TE) properties is significant for the engineering applications of inorganic TE materials. In this work, a novel nanodomain strategy is developed for Ag Te compounds to yield 40% and 200% improved compressive strength (160 MPa) and fracture strain (16%) when compared to domain-free samples (115 MPa and 5.5%, respectively).

Realizing Excellent Structural and Thermoelectric Performance in MgSb-Based Alloys by Manipulating Mg Intrinsic Migration Kinetics with Interstitial Ni Doping.

N-type MgSb is attracting increasing focus for its outstanding room-temperature (RT) thermoelectric (TE) performance; however, achieving reliable n-type conduction remains challenging due to negatively charged Mg vacancies. Doping with compensation charges is generally used but does not fundamentally resolve the high intrinsic activity and easy formation of Mg vacancies. Herein, a robust structural and thermoelectric performance is obtained by manipulating Mg intrinsic migration activity by precisely incorporating Ni at the interstitial site.

Enhanced Contact Performance and Thermal Tolerance of Ni/BiTe Joints for BiTe-Based Thermoelectric Devices.

Ni metal has been widely used as a barrier layer in BiTe-based thermoelectric devices, which establishes stable joints to link BiTe-based legs and electrodes. However, the Ni/BiTe joints become very fragile when the devices were exposed to high temperature, causing severe performance deterioration and even device failure. Herein, stable Ni/BiTe joints have been established by arc spraying of the Ni barrier layer on the BiTe-based alloys.

Manipulating the Interfacial Band Bending For Enhancing the Thermoelectric Properties of 1T'-MoTe /Bi Te Superlattice Films.

Interfacial charge effects, such as band bending, modulation doping, and energy filtering, are critical for improving electronic transport properties of superlattice films. However, effectively manipulating interfacial band bending has proven challenging in previous studies. In this study, (1T'-MoTe ) (Bi Te ) superlattice films with symmetry-mismatch were successfully fabricated via the molecular beam epitaxy.

The roles of ubiquitin-proteasome system and regulator of G protein signaling 4 in behavioral sensitization induced by a single morphine exposure.

Aims: Opioid addiction is a major public health issue, yet its underlying mechanism is still unknown. The aim of this study was to explore the roles of ubiquitin-proteasome system (UPS) and regulator of G protein signaling 4 (RGS4) in morphine-induced behavioral sensitization, a well-recognized animal model of opioid addiction.

Methods: We explored the characteristics of RGS4 protein expression and polyubiquitination in the development of behavioral sensitization induced by a single morphine exposure in rats, and the effect of a selective proteasome inhibitor, lactacystin (LAC), on behavioral sensitization.

Direct observation of cation diffusion driven surface reconstruction at van der Waals gaps.

Weak interlayer van der Waals (vdW) bonding has significant impact on the surface/interface structure, electronic properties, and transport properties of vdW layered materials. Unraveling the complex atomistic dynamics and structural evolution at vdW surfaces is therefore critical for the design and synthesis of the next-generation vdW layered materials. Here, we show that Ge/Bi cation diffusion along the vdW gap in layered GeBiTe (GBT) can be directly observed using in situ heating scanning transmission electron microscopy (STEM).

Tuning Thermoelectric Conversion Performance of BiSbTe/Epoxy Flexible Films with Dot Magnetic Arrays.

Embedding of magnetic functional units into the thermoelectric (TE) materials has been demonstrated to be an effective way to enhance the TE conversion performance. However, the magnetic functional units in TE materials are all randomly distributed. In this paper, to explore the effect of the ordering of the magnetic functional units on TE conversion performance, a series of BiSbTe/epoxy flexible thermoelectromagnetic (TEM) films with dot magnetic arrays were successfully prepared by a two-step screen printing combined with a hot pressing process.

"Cluster Bomb" Based Bismuth Nano-in-Micro Spheres Formed Dry Powder Inhalation for Thermo-Radio Sensitization Effects of Lung Metastatic Breast Cancer.

Lung metastatic breast cancer (LMBC) is mainly diagnosed through CT imaging and radiotherapy could be the most common method in the clinic to inhibit tumor proliferation. While the sensitivity of radiotherapy is always limited due to the hypoxic tumor microenvironment and high doses of irradiation easily induce systemic cytotoxicity. Metal-based materials applied as radiosensitizers have been widely investigated to improve efficiency and reduce the doses of irradiation.