Search

Strain engineering is a popular approach for manipulating material properties through modifying crystal structures and/or electron-lattice interactions. In this work, we used a phase transition material, vanadium dioxide (VO) as an active and reconfigurable substrate to generate a controllable strain. Amorphous ferromagnetic Ni thin films were deposited on the (010)-VO/(0001)-AlO substrates. It is observed that the magnetic moments of the Ni thin film were modulated by interfacing it with the VO thin film. We observed a hysteresis in the magnetic moment-temperature curves in the vicinity of the metal-insulator transition of the VO thin films at a low magnetic field bias (< 30 Oe). This result can be attributed to magnetoelastic coupling between the Ni and VO thin films through a reversible structural phase transition. As the bias field was increased, the hysteresis was suppressed and eventually disappeared. The competition between the magnetoelastic energy and external Zeeman energy can explain these behaviors. Our observations suggest a promising approach to dynamically controlling the properties of functional thin films by strain engineering. [ABSTRACT FROM AUTHOR]

Electric-field control of the anomalous Hall effect (AHE) was investigated in Fe40Pt60/(001)-Pb(Mg1/3Nb2/3)0.67Ti0.33O3 (FePt/PMN-PT) multiferroic heterostructures at room temperature. It was observed that a very large Hall resistivity change of up to 23.9% was produced using electric fields under a magnetic field bias of 100 Oe. A pulsed electric field sequence was used to generate nonvolatile strain to manipulate the Hall resistivity. Two corresponding nonvolatile states with distinct Hall resistivities were achieved after the electric fields were removed, thus enabling the encoding of binary information for memory applications. These results demonstrate that the Hall resistivity can be reversibly switched in a nonvolatile manner using programmable electric fields. Two remanent magnetic states that were created by electric-field-induced piezo-strain from the PMN-PT were attributed to the nonvolatile and reversible properties of the AHE. This work suggests that a low-energy-consumption-based approach can be used to create nonvolatile resistance states for spintronic devices based on electric-field control of the AHE. [ABSTRACT FROM AUTHOR]

There has been no widely accepted DNA barcode for species identification of Demodex. In this study, we attempted to solve this issue. First, mitochondrial cox1-5′ and 12S gene fragments of Demodex folloculorum, D. brevis, D. canis, and D. caprae were amplified, cloned, and sequenced for the first time; intra/interspecific divergences were computed and phylogenetic trees were reconstructed. Then, divergence frequency distribution plots of those two gene fragments were drawn together with mtDNA cox1-middle region and 16S obtained in previous studies. Finally, their identification efficiency was evaluated by comparing barcoding gap. Results indicated that 12S had the higher identification efficiency. Specifically, for cox1-5′ region of the four Demodex species, intraspecific divergences were less than 2.0%, and interspecific divergences were 21.1-31.0%; for 12S, intraspecific divergences were less than 1.4%, and interspecific divergences were 20.8-26.9%. The phylogenetic trees demonstrated that the four Demodex species clustered separately, and divergence frequency distribution plot showed that the largest intraspecific divergence of 12S (1.4%) was less than cox1-5′ region (2.0%), cox1-middle region (3.1%), and 16S (2.8%). The barcoding gap of 12S was 19.4%, larger than cox1-5′ region (19.1%), cox1-middle region (11.3%), and 16S (13.0%); the interspecific divergence span of 12S was 6.2%, smaller than cox1-5′ region (10.0%), cox1-middle region (14.1%), and 16S (11.4%). Moreover, 12S has a moderate length (517 bp) for sequencing at once. Therefore, we proposed mtDNA 12S was more suitable than cox1 and 16S to be a DNA barcode for classification and identification of Demodex at lower category level. [ABSTRACT FROM AUTHOR]

A constitutive model for the stress-strain relationship of single forest root system was developed in order to provide theoretical foundations for the mechanisms of soil-reinforcement by root system and offer a reliable basis for the analysis of root tensile strength character. This study started a general form of linear and non-linear stress-strain relation that was mathematically defined by four boundary conditions observed in typical tensile tests of single roots. The parameters of the model were determined by experiment data and had definite physical meaning. The model was verified by experiment data, which showed that the calculated values were in good agreement with the experimental single root tensile test results. The constitutive model was validated and found to be feasible for modeling single root tensile stress. [ABSTRACT FROM AUTHOR]

The reversible topotactic phase transformation between brownmillerite SrCoO2.5 to perovskite SrCoO3 has attracted more and more attention for potential applications as solid oxide fuels and electrolysis cells. However, the relatively easy transformation result from small thermal stable energy barriers between the two phases leads to unstable the structures. In the paper, amounts of SrCoO3-δ films have been prepared by pulsed laser deposition at optimized growth conditions with the temperature range of 590-720°C. The X-ray diffraction (XRD) results demonstrated that a phase competition emerged around 650°C. The Gibbs free energies of two phases at high temperature revealed the difference of stability of these two phases under different growth temperature. The optical spectroscopies and X-ray photoelectron spectroscopies were used to verify the electronic structure and chemical state differences between the two phases with distinct crystal structures. [ABSTRACT FROM AUTHOR]

The development of portable and wearable electronic devices continues to increase the demand for miniature energy storage units. Here, we fabricate the flexible micro-supercapacitors (MSCs) through direct heating pattern on graphene oxide film. The shape designable MSCs are based on planar reduced graphene oxide/graphene oxide (rGO/GO) structure, with rGO as electrode and GO as separator. The GO area heated by heating pen is reduced to rGO, and the area with no heating is still GO. The interdigitated MSC made at 400 °C delivers high area capacitance of 94.8 mF cm−2 at current density of 0.25 mA cm−2 within poly(vinyl alcohol) (PVA)/H 2 SO 4 gel electrolyte. It provides high energy density of 10.7 mWh cm−2 at power density of 112.6 mW cm−2. In addition, it also has excellent mechanical stability, with basically unchanged area capacitance from 0° to 180° bending angles. The MSCs with shapes of spiral, concentric circle and eight-trigrams are also fabricated via this method. The results indicate that heating pattern on GO films to build flexible MSC is a promising and low-cost new method to fabricate energy storage equipment for future electronic devices. Image 1 [ABSTRACT FROM AUTHOR]

In order to study the factors affecting superconductivity of Sr 2 CuO 3 + δ , polarized X-ray absorption spectra (XAS) were measured at Cu L 23 edge and O K edge of an over-doped single crystal specimen. This polarized XAS study reveals a distinctive anisotropic local electronic structure of Cu coordination: the unoccupied states are dominated by the in-plane components of Cu 3d x 2 − y 2 and O 2p x , y . However, the signal from the unoccupied out-of-plane O 2p z and Cu 3d z 2 states also appear. Furthermore, the detailed analysis of Cu L 3 -edge XAS at 300 K and 17.3 K indicates that the conductive carrier partly shifts from out-of-plane to in-plane in the superconducting state. Theoretical calculation of Cu L 23 -edge core level spectra based on Charge Transfer Multiplet theory is fairly consistent with above experimental results. [ABSTRACT FROM AUTHOR]

Aerobic glycolysis is a hallmark of cancer and is regulated by growth factors, protein kinases and transcription factors. However, it remains poorly understood how these components interact to regulate aerobic glycolysis coordinately. Here, we show that sine oculis homeobox 1 (SIX1) phosphorylation integrates growth factors (e.g. TGFβ, EGF) to control aerobic glycolysis and determines its tumor-promoting activity. SIX1 is phosphorylated at serine 225 (S225) by growth factors-activated protein kinases ERK1/2 and its phosphorylation is responsible for glycolysis stimulated by some growth factors. SIX1 is dephosphorylated by the atypical protein phosphatase eyes absent 4 (EYA4). Phosphorylation blocks non-canonical ubiquitination and degradation of SIX1 through the E3 ubiquitin ligase FZR1. Unexpectedly, the non-canonical phosphorylation mimic SIX1 (S225K), but not the canonical phosphorylation mimic SIX1 (S225D/E), phenocopies the effects of SIX1 phosphorylation on glycolysis and cancer cell growth and metastasis in vitro and in mice. Compared to normal liver tissues, SIX1 phosphorylation at S225 (pS225) is upregulated in human liver cancer tissues. ERK1/2 expression is positively correlated with pS225 and EYA4 expression is negatively associated with pS225 in liver cancer specimens. Moreover, low expression of pS225 had longer disease-free survival and overall survival in patients with liver cancer. Thus, we identify a common mechanism underlying growth factors-mediated glycolysis, and provide a previously unidentified mode for non-classical phosphorylation mimics of a protein. Targeting growth factors/SIX1 signaling pathway may be beneficial to cancer treatment., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Objective: Electrical impedance tomography (EIT) enables continuous image acquisition, facilitating real-time measurements of ventilation and perfusion at the clinical bedside. Experimental and clinical studies on controversial effects of thoracic epidural blockade (TEB) with local anesthetics on ventilation-perfusion(V/Q) matching and hypoxia during one lung ventilation (OLV) are rare. The aim of this study was to use EIT to investigate the effects of TEB combined with general anesthesia on pulmonary perfusion distribution and V/Q matching during one-lung ventilation., Design: Single-centered, prospective, unblinded, randomized, parallel-group clinical trial., Setting: Surgical suite of a university-affiliated teaching hospital., Patients: Thirty patients prepared for thoracic surgery were randomly assigned to either the control group or the TEB group, which received a combination of thoracic epidural blockade and general anesthesia., Measurements: EIT measurements and blood gas analysis were conducted in the lateral position during two-lung ventilation(T 0 ), 15 min after OLV(T 1 ), and 15 min after administration of 0.25 % ropivacaine or 0.9 % saline via epidural delivery during OLV(T 2 ). Hemodynamic and respiratory parameters were recorded, and Dead Space%, Shunt%, and V/Q Match% were calculated based on blood gas analysis and EIT images., Results: Mean arterial pressure (p < 0.05) significantly decreased 15 min after TEB, while there were no significant changes in heart rate among the 30 patients (p = 0.547). OLV resulted in a significant decrease in arterial oxygen partial pressure/inspired oxygen fraction (PaO 2 /FiO 2 ) from T 0 to T 1 in both groups. The PaO 2 /FiO 2 in the TEB group was significantly lower after epidural administration of the local anesthetic (p < 0.05). Shunt- ABG (%) was significantly higher in the TEB group compared to the control group at T 2 (p < 0.05). TEB increased non-ventilated perfusion distribution(p < 0.05), and Shunt-EIT % (p < 0.05) and reduced Matched Region % (p < 0.05), while Dead Space-EIT % remained (p = 0.499)., Conclusions: Based on the contrast-enhanced EIT evaluation of pulmonary perfusion and ventilation, TEB appears to induce a V/Q mismatch in patients undergoing OLV in the lateral position for thoracic surgery., Trial Registration: ClinicalTrials.gov, NCT04730089. Registration on January 25th, 2021., Competing Interests: Declaration of competing interest The authors declare no potential conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

De novo lipogenesis (DNL), a hallmark of cancer, facilitates tumor growth and metastasis. Therapeutic drugs targeting DNL are being developed. However, how DNL is directly regulated in cancer remains largely unknown. Here, transcription factor sine oculis homeobox 1 (SIX1) is shown to directly increase the expression of DNL-related genes, including ATP citrate lyase (ACLY), fatty acid synthase (FASN), and stearoyl-CoA desaturase 1 (SCD1), via histone acetyltransferases amplified in breast cancer 1 (AIB1) and lysine acetyltransferase 7 （HBO1/KAT7）, thus promoting lipogenesis. SIX1 expression is regulated by insulin/lncRNA DGUOK-AS1/microRNA-145-5p axis, which also modulates DNL-related gene expression as well as DNL. The DGUOK-AS1/microRNA-145-5p/SIX1 axis regulates liver cancer cell proliferation, invasion, and metastasis in vitro and in vivo. In patients with liver cancer, SIX1 expression is positively correlated with DGUOK-AS1 and SCD1 expression and is negatively correlated with microRNA-145-5p expression. DGUOK-AS1 is a good predictor of prognosis. Thus, the DGUOK-AS1/microRNA-145-5p/SIX1 axis strongly links DNL to tumor growth and metastasis and may become an avenue for liver cancer therapeutic intervention., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

As a quasi-layered ferrimagnetic material, Mn 3 Si 2 Te 6 nanoflakes exhibit magnetoresistance behavior that is fundamentally different from their bulk crystal counterparts. They offer three key properties crucial for spintronics. First, at least 10 6 times faster response compared to that exhibited by bulk crystals has been observed in current-controlled resistance and magnetoresistance. Second, ultralow current density is required for resistance modulation (∼5 A/cm 2 ). Third, electrically gate-tunable magnetoresistance has been realized. Theoretical calculations reveal that the unique magnetoresistance behavior in the Mn 3 Si 2 Te 6 nanoflakes arises from a magnetic field induced band gap shift across the Fermi level. The rapid current induced resistance variation is attributed to spin-orbit torque, an intrinsically ultrafast process (∼nanoseconds). This study suggests promising avenues for spintronic applications. In addition, it highlights Mn 3 Si 2 Te 6 nanoflakes as a suitable platform for investigating the intriguing physics underlying chiral orbital moments, magnetic field induced band variation, and spin torque.

This paper proposes a fluid classifier for a tight reservoir using a quantum neural network (QNN). It is difficult to identify the fluid in tight reservoirs, and the manual interpretation of logging data, which is an important means to identify the fluid properties, has the disadvantages of a low recognition rate and non-intelligence, and an intelligent algorithm can better identify the fluid. For tight reservoirs, the logging response characteristics of different fluid properties and the sensitivity and relevance of well log parameter and rock physics parameters to fluid identification are analyzed, and different sets of input parameters for fluid identification are constructed. On the basis of quantum neural networks, a new method for combining sample quantum state descriptions, sensitivity analysis of input parameters, and wavelet activation functions for optimization is proposed. The results of identifying the dry layer, gas layer, and gas-water co-layer in the tight reservoir in the Sichuan Basin of China show that different input parameters and activation functions affect recognition performance. The proposed quantum neural network based on hybrid parameters and a wavelet activation function has higher fluid identification accuracy than the original quantum neural network model, indicating that this method is effective and warrants promotion and application., (© 2024. The Author(s).)

Photodetectors have been applied to pivotal optoelectronic components of modern optical communication, sensing, and imaging systems. As a room-temperature ferroelectric van der Waals semiconductor, 2D α-In 2 Se 3 is a promising candidate for a next-generation optoelectronic material because of its thickness-dependent direct bandgap and excellent optoelectronic performance. Previous studies of photodetectors based on α-In 2 Se 3 have been rarely focused on the modulated relationship between the α-In 2 Se 3 intrinsic ferroelectricity and photoresponsivity. Herein, a simple integrated process and high-performance photodetector based on an α-In 2 Se 3 /Si vertical hybrid-dimensional heterojunction was constructed. Our photodetector in the ferroelectric polarization up state accomplishes a self-powered, highly sensitive photoresponse with an on/off ratio of 4.5 × 10 5 and detectivity of 1.6 × 10 13 Jones, and it also shows a fast response time with 43 μs. The depolarization field generated by the remanent polarization of ferroelectrics in α-In 2 Se 3 provides a strategy for enhancement and modulation of photodetection. The negative correlation was discovered because the enhancement photoresponsivity factor of ferroelectric modulation competes with the photovoltaic behavior within the α-In 2 Se 3 /Si heterojunction. Our research highlights the great potential of the high-efficiency heterojunction photodetector for future object recognition and photoelectric imaging.

An approach to autogenerate voxel-based absorbed dose for nuclear medicine is proposed using generative adversarial networks. The method is based on image-to-image transformation and promises to achieve real-time visualization of the absorbed dose and optimization of therapeutic strategies. The activity-density superimposed image is input to generator (G) as a reference image to generate a pseudoabsorbed dose image (DI), which is then mixed with ground truth (GT) DI and recognized by discriminator (D). If the pseudoimage is recognized, the information is fed back, and G regenerates a pseudodose image until D drops to obtain a lifelike DI. As a feasibility study, we used the dose distribution of segmented human anatomy from different sources and activities as training and test datasets. The activity source was assumed to be 1, 2, 3, 4, or 7 subsource blocks. The 3-subsource model was used as the test dataset, and the others were used as the training dataset. The activity distribution in the subsource was assumed to be uniform or heterogeneous (i.e., Gaussian diffusion with sigma 0.0, 0.3, or 0.6). Differences were assessed by Gamma analysis. Results showed that the same or quasi-inhomogeneity model can well predict the dose distribution of different activity-inhomogeneity. Although the 1-source model was trained with very few datasets, it showed an optimal balance between accuracy and training efficiency. There were offsets in the mean absorbed dose between the predicted and GT, but they all showed a higher Gamma-pass-rate (> 93%) and ~ 10% std., (© 2022. Australasian College of Physical Scientists and Engineers in Medicine.)

The sun (∼6,000 K) and outer space (∼3 K) are two significant renewable thermodynamic resources for human beings on Earth. The solar thermal conversion by photothermal (PT) and harvesting the coldness of outer space by radiative cooling (RC) have already attracted tremendous interest. However, most of the PT and RC approaches are static and monofunctional, which can only provide heating or cooling respectively under sunlight or darkness. Herein, a spectrally self-adaptive absorber/emitter (SSA/E) with strong solar absorption and switchable emissivity within the atmospheric window (i.e., 8 to 13 μm) was developed for the dynamic combination of PT and RC, corresponding to continuously efficient energy harvesting from the sun and rejecting energy to the universe. The as-fabricated SSA/E not only can be heated to ∼170 °C above ambient temperature under sunshine but also be cooled to 20 °C below ambient temperature, and thermal modeling captures the high energy harvesting efficiency of the SSA/E, enabling new technological capabilities.

Electric-field (E-field) control of magnetic switching provides an energy-efficient means to toggle the magnetic states in spintronic devices. The angular tunneling magnetoresistance (TMR) of an magnetic tunnel junction (MTJ)/PMN-PT magnetoelectronic hybrid indicates that the angle-dependent switching fields of the free layer can decrease significantly subject to the application of an E-field. In particular, the switching field along the major axis is reduced by 59% from 28.0 to 11.5 Oe as the E-field increases from 0 to 6 kV/cm, while the TMR ratio remains intact. The switching boundary angle decreases (increases) for the parallel (antiparallel) to antiparallel (parallel) state switch, resulting in a shrunk switching window size. The non-volatile and reversible 180° magnetization switching is demonstrated by using E-fields with a smaller magnetic field bias as low as 11.5 Oe. The angular magnetic switching originates from competition among the E-field-induced magnetoelastic anisotropy, magnetic shape anisotropy, and Zeeman energy, which is confirmed by micromagnetic simulations., Competing Interests: The authors declare no competing interests., (© 2021 The Author(s).)

The electrochemical performance of supercapacitors is suppressed by a large number of defects in the interface of heterostructure due to lattice mismatch. In this paper, the (001) oriented rutile MnO 2 thin films with different thicknesses were grown on rutile TiO 2 substrates. The lattice mismatch between film and substrate was minimized through a Ti diffusion self-adapting layer. The energy-dispersive spectroscopy mappings were used to measure the diffusion range of Ti. The results of high-resolution X-ray diffraction confirmed that the dependence of the out-of-plane lattice parameter on the thickness was consistent with the self-adapting interface model, indicating that Ti diffusion can indeed alleviate the lattice mismatch. In addition, the results of the synchrotron soft X-ray absorption spectrum indicated that the capacitance of the thin films with a large proportion of Ti diffusion increased with electrons involved in the reaction. Although the decrease of carrier density and conductivity of the thinner films depressed the electrochemical activity, it is worth mentioning that the film we designed still has considerable specific capacitance even when it is very thin, which can provide a new idea for the development of thinner and larger capacity potential micro-supercapacitors.

The VO₂ thin films with sharp metal⁻insulator transition (MIT) were epitaxially grown on (001)-oriented Yttria-stabilized zirconia substrates (YSZ) using radio-frequency (RF) magnetron sputtering techniques. The MIT and structural phase transition (SPT) were comprehensively investigated under in situ temperature conditions. The amplitude of MIT is in the order of magnitude of 10⁴, and critical temperature is 342 K during the heating cycle. It is interesting that both electron concentration and mobility are changed by two orders of magnitude across the MIT. This research is distinctively different from previous studies, which found that the electron concentration solely contributes to the amplitude of the MIT, although the electron mobility does not. Analysis of the SPT showed that the (010)-VO₂/(001)-YSZ epitaxial thin film presents a special multi-domain structure, which is probably due to the symmetry matching and lattice mismatch between the VO₂ and YSZ substrate. The VO₂ film experiences the SPT from the M1 phase at low temperature to a rutile phase at a high temperature. Moreover, the SPT occurs at the same critical temperature as that of the MIT. This work may shed light on a new MIT behavior and may potentially pave the way for preparing high-quality VO₂ thin films on cost-effective YSZ substrates for photoelectronic applications.