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The fundamental logic states of 1 and 0 in Complementary Metal-Oxide-Semiconductor (CMOS) are essential for modern high-speed non-volatile solid-state memories. However, the accumulated storage signal in conventional physical components often leads to data distortion after multiple write operations. This necessitates a write-verify operation to ensure proper values within the 0/1 threshold ranges. In this work, a non-gradual switching memory with two distinct stable resistance levels is introduced, enabled by the asymmetric vertical structure of monolayer vacancy-induced oxidized Ti3C2Tx MXene for efficient carrier trapping and releasing. This non-cumulative resistance effect allows non-volatile memories to attain valid 0/1 logic levels through direct reprogramming, eliminating the need for a write-verify operation. The device exhibits superior performance characteristics, including short write/erase times (100 ns), a large switching ratio (≈3 × 104), long cyclic endurance (>104 cycles), extended retention (>4 × 106 s), and highly resistive stability (>104 continuous write operations). These findings present promising avenues for next-generation resistive memories, offering faster programming speed, exceptional write performance, and streamlined algorithms.
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Prostate cancer remains the most prevalent cancer among men worldwide; however, as a sex hormone-dependent cancer, sex hormones and their receptor signaling play an important role in the development and progression of cancer. Most current treatment options for prostate cancer thus revolve around the inhibition of androgen signaling (eg, ADT), which, although effective in the early stages, eventually progresses to treatment-resistant prostate cancer with no effective follow-up options. Recent studies have shown that among the nuclear receptor family members, in addition to androgen receptors, estrogen receptor (ER) plays an important biological function as a transcription factor and regulatory protein in various cancers, acting either directly or indirectly by forming homodimers or heterodimers with ligands. In this paper, we review the application of ERß in animal models and in vitro experiments in the last 5 years, as well as the presence and role of some of its splice variants. We summarize the overview and update of ERß in prostate cancer, and provide a corresponding analysis of some current research disagreements. Its crosstalk action on some important cancer growth-related signaling pathways (eg, TGF-ß and ERK), regulation of downstream target proteins (eg, nuclear translocation of EGFR and expression of oncogenic -related protein MMP-2), and interactions with related ERß co-regulators (eg, ZFHX3), agonists, and antagonists in prostate cancer are highlighted, and the resulting effects on tumor progression are described. In addition, the paper describes its current potential clinical application as a novel therapeutic strategy and some of the challenges it faces.
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Receptor beta de Estrogênio , Neoplasias da Próstata , Animais , Linhagem Celular Tumoral , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Humanos , Masculino , Próstata/patologia , Neoplasias da Próstata/patologia , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Receptores de Estrogênio/metabolismoRESUMO
N-heterocyclic carbene (NHC) has been widely used as an organocatalyst for both umpolung and non-umpolung chemistry. Previous works mainly focus on species including Breslow intermediate, azolium enolate intermediate, homoenolate intermediate, alkenyl acyl azolium intermediate, etc. Notably, the NHC-bound alkynyl acyl azolium has emerged as an effective intermediate to access functionalized cyclic molecular skeleton until very recently. In this review, we summarized the generation and reactivity of the NHC-bound alkynyl acyl azolium intermediates, which covers the efforts and advances in the synthesis of achiral and axially chiral cyclic scaffolds via the NHC-bound alkynyl acyl azolium intermediates. In particular, the mechanism related to this intermediate is discussed in detail.
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Metano , Catálise , Metano/químicaRESUMO
In this paper, a strategy to achieve a simultaneous wavefront shaping and polarization rotation, without compromising the number of pixels and energy efficiency as well as having broadband operation range, is proposed. This strategy is based on the application of a spin-decoupled phase metasurface composed by only one set of metal-insulator-metal (MIM) umbrella-shaped chiral unit cells. Quasi-non-dispersive and spin-decoupled phase shift can be achieved simply by changing single structural parameter of the structure. By further merging the Pancharatnam-Berry (PB) geometric phase, conversion of an incident LP light beam into right- and left-handed circularly polarized reflected beams with similar amplitudes, desired phase profiles and controlled phase retardation on a nanoscale is enabled with high efficiency. Based on the proposed strategy, a polarization-insensitive hologram generator with control optical activity, and a multiple ring vortex beam generator are realized. The results obtained in this work provide a simple and pixel-saving approach to the design of integratable and multitasking devices combining polarization manipulation and wavefront shaping functions, such as vectorial holographic generators, multifocal metalenses, and multichannel vector beam generators.
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Two-dimensional (2D) organic-inorganic hybrid perovskites, which possess outstanding optical and electrical properties, are promising semiconductor materials that have attracted significant interest in widespread applications. The frictional behavior of 2D perovskite materials with other transparent conductive materials, such as indium tin oxide (ITO), offers promising developments in optoelectronic devices. Therefore, the understanding of this frictional behavior is essential. Atomic force microscopy (AFM) is employed here to measure the frictional behavior between the (001) plane of the 2D organic-inorganic hybrid (C4H9NH3)2PbBr4 perovskite and the (111) plane of the ITO. The experimental analyses characterizing the nature of the friction in a single-crystalline heterojunction are reported. Based on the results of the analyses of interfaces between 2D monolayer perovskites and ITO, a strong anisotropy of friction is clearly demonstrated. The anisotropy of friction is observed as a four-fold symmetry with low a frictional coefficient, 0.035, in misaligned contacts, and, 0.015, in aligned contacts in the heterojunction configuration. In addition, atomistic simulations reveal underlying frictional mechanisms in the dynamical regimes. A new phenomenon discovered in the studies establishes that the measured frictional anisotropy surprisingly depends on the number of atomic layers in the 2D perovskite. The frictional anisotropy decreases significantly with the increase in the number of layers up to 16 layers, and then it becomes independent of the thickness. Our results are predicted to be of a general nature and should be applicable to other 2D hybrid perovskite heterojunction configurations, and thus, furthers the development of adaptive and stretchable optoelectronic nanodevices.
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The mechanical properties of size-dependent nanowires are important in nano-electro-mechanical systems (NEMSs), and have attracted much research interest. Characterization of the size effect of nanowires in atmosphere directly to broaden their practical application instead of just in high vacuum situations, as reported previously, is desperately needed. In this study, we systematically studied the Young's modulus of vertical ZnO nanowires in atmosphere. The diameters ranged from 48 nm to 239 nm with a resonance method using non-contact atomic force microscopy. The values of Young's modulus in atmosphere present extremely strong increasing tendency with decreasing diameter of nanowire due to stronger surface atomic bonds compared with that in vacuum. A core-shell model for nanowires is proposed to explore the Young's modulus enhancement in atmosphere, which is correlated with atoms of oxygen occurring near the nanowire surface. The modified model is more accurate for analyzing the mechanical behavior of nanowires in atmosphere compared with the model in vacuum. Furthermore, it is possible to use this characterization method to measure the size-related elastic properties of similar wire-sharp nanomaterials in atmosphere and estimate the corresponding mechanical behavior. The study of the size-dependent Young's modulus in ZnO nanowires in atmosphere will improve the understanding of the mechanical properties of nanomaterials as well as providing guidance for applications in NEMSs, nanogenerators, biosensors and other related areas.
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A chip-size vertically aligned nanowire (NW) resonator arrays (VNRs) device has been fabricated with simple one-step lithography process by using grown self-assembled zinc oxide (ZnO) NW arrays. VNR has cantilever diameter of 50 nm, which breakthroughs smallest resonator record (>100 nm) functioning in atmosphere. A new atomic displacement sensing method by using atomic force microscopy is developed to effectively identify the resonance of NW resonator with diameter 50 nm in atmosphere. Size-effect and half-dimensional properties of the NW resonator have been systematically studied. Additionally, VNR has been demonstrated with the ability of detecting nanofilm thickness with subnanometer (<10(-9)m) resolution.
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How properties change as 1D nanomaterials reduce in length to 0D, that is, the properties of 0.5D nanomaterial, are studied via photoelectric changes in ZnO nanowires. The photoelectric property of this 0.5D nanomaterial changes significantly as the 3D nanoconfinement is reinforced. This finding can be expanded to more properties and materials to profoundly impact fields of nanoscience, nanodevices, and nanoelectronics.
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We demonstrate an innovative technique for the direct measurement on the shear modulus of an individual nanorod. This measurement is based on atomic force microscopy (AFM) and microfabrication techniques. A nanorod is first aligned along the edge of a small trench in a silicon substrate, and then one end of the nanorod is fixed on the substrate. When an AFM tip scans over the nanorod in contact mode, the nanorod will be twisted by the comprehensive action from the force of the AFM tip, confinement from the trench edge and the fixing end. The shear deformation and the corresponding force that caused the deformation can be retrieved from topography and lateral force image, respectively. By small-angle approximation, the shear modulus of the ZnO NR, which has a radius of 166 nm and a length of 4 µm, is measured to be 8.1 ± 1.9 GPa. This method can be applied directly to characterize the shear modulus of any nanowire/nanorod that possesses a polygon cross section.
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In the pursuit of artificial neural systems, the integration of multimodal plasticity, memory retention, and perceptual functions stands as a paramount objective in achieving neuromorphic perceptual components inspired by the human brain, to emulating the neurological excitability tuning observed in human visual and respiratory collaborations. Here, an artificial visual-respiratory synapse is presented with monolayer oxidized MXene (VRSOM) exhibiting synergistic light and atmospheric plasticity. The VRSOM enables to realize facile modulation of synaptic behaviors, encompassing postsynaptic current, sustained photoconductivity, stable facilitation/depression properties, and "learning-experience" behavior. These performances rely on the privileged photocarrier trapping characteristics and the hydroxyl-preferential selectivity inherent of oxidized vacancies. Moreover, environment recognitions and multimodal neural network image identifications are achieved through multisensory integration, underscoring the potential of the VRSOM in reproducing human-like perceptual attributes. The VRSOM platform holds significant promise for hardware output of human-like mixed-modal interactions and paves the way for perceiving multisensory neural behaviors in artificial interactive devices.
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We have systematically investigated the intrinsic electrical property of a single crystal zinc oxide (ZnO) micro/nanobelt (MB/NB) using a conductive atomic force microscopy (AFM) technique. By mounting one end of the MB/NB on a flat nonconductive silicon substrate, a platform for performing electrical property characterization using conductive current AFM is established. The quantitative characterization of the electrical resistance of the MB/NBs was performed by acquiring I-V curves for the MB/NB in between the electrode and the conductive AFM tip. The resistance of the single crystalline ZnO MB/NB was measured to be exponentially dependent on the length of the MB/NB. A systematic model based on the anisotropic velocity of the carriers in the crystal planes has been proposed and fits the experimental measurement well. This research reveals that the electrical resistance shows a nonlinear length dependence in the semiconducting single crystal MB/NB, which is significantly different from the bulk counterpart. Understanding such a property could definitely improve the design and the performance of next generation electrical nanodevices.
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We report a simple and effective vapor deposition method for directly growing ultra-long, laterally aligned, zinc oxide (ZnO) nanorod arrays only on the side edges of a bare silicon (Si) substrate without using any catalysts and precursors. The growth on the top surface of the substrate is restrained by controlling the flow of source vapor in a tube furnace through the chemical vapor solid process. The optimized growth parameters have been thoroughly investigated and identified. Direct growth of laterally aligned ZnO nanowire arrays on the desired surface of the substrate is successfully achieved. A vapor solid mechanism with source vapor flow rate control has been proposed to explain the synthesis: ZnO nanodots first form on the bare Si substrate side edges due to the local large binding energy and high zinc (Zn) vapor concentration, and then nanorods epitaxially grow from the nanodots. In addition, the lateral, ultra-long ZnO nanorods grown on orthogonal silicon microelectrodes are achieved and could be expected to find important applications in a bottom-up way of fabricating the next generation nanoelectronics.
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Accurate evaluation of emergencies is a critical concern in long-duration space flights. Accordingly, we studied the effect of 45 days of - 6° head-down bed rest - a model that simulates the conditions in microgravity environments - on the evaluation of orally reported emergencies. Sixteen male participants listened to corresponding emergency scenarios and assessed the severity of these situations eight times before, during and after bed rest. The results revealed a ' recency effect': compared with emergency descriptions in the order of serious to mild, those framed in the reverse order were judged to be more serious. However, the severity ratings did not vary with time spent in the simulated microgravity environment. These findings are similar to those observed in a regular environment on Earth, indicating that the design principles of information presentation for situations on Earth may also be extended to designs intended for outer space. PRACTITIONER SUMMARY: A recency effect was found in the evaluation of orally reported emergencies under simulated microgravity conditions. The design principles of information presentation for situations on Earth may also be extended to designs intended for outer space.
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Comunicação , Emergências/psicologia , Julgamento , Simulação de Ausência de Peso/psicologia , Adulto , Decúbito Inclinado com Rebaixamento da Cabeça , Humanos , Masculino , Tempo de Reação , Fatores de Tempo , Adulto JovemRESUMO
This paper proposes a adaptive reaching law-based sliding mode control (SMC) method for maintaining favorable velocity control performance of permanent magnet synchronous motors (PMSMs) under internal and external perturbations. An adaptive switching power reaching law (ASPRL) is designed, which contains adaptive terms and state variables of the sliding mode surface function. This augmented reaching law decreases the chatter of the control system and increases the rate at which the state variables of the system reach the sliding mode surface. Additionally, a Luenberger observer load torque (LOLT) is designed to observe the external load and provide feedback to the velocity controller, reducing the impact of load disturbances and improving the jamming performance of the controller. Simulation experiments confirm that ASPRL reduces buffeting, decreases overshoot, and shortens response time, demonstrating its advantages in PMSM control.
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As high-voltage output and fast response devices, triboelectric nanogenerators (TENGs) are widely used for sensors with fast and high-sensitivity performance. As a primary electrical signal, the waveform output provides an accurate and rapid response to external stimulus parameters such as press and slide. Here, based on mosaic charging and residual charge theories, the contact charging principle of TENGs is further discussed. Moreover, a wavy structure is obtained in the vertical contact separation and lateral sliding modes to further study the influence of external parameters applied to TENGs, which thus helps further the understanding of the output waveforms. The experimental results show that wavy TENGs have output properties that are excellent compared to those of TENGs with flat structures, such as longer charging and discharging times and more complex waveforms. By researching the waveform in depth, our work will provide new prospects for application in various sensors of interactive wearable systems, intelligent robots, and optoelectronic devices based on TENGs.
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Purpose: To evaluate the relationship between endoscopic ureteral inflammatory edema (UIE) and ureteral lumen, formulate a preliminary grading method for the severity of UIE, and analyze the impact of different grades of UIE on endoscopic ureteral calculi surgery and prognosis. Materials and methods: We retrospectively analyzed 185 patients who underwent ureteroscopic lithotripsy (URSL) for upper urinary tract stones between January 2021 and November 2021. The UIE grade and lumen conditions were assessed by endoscopic observation. The effect of UIE grade on URSL and on patient prognosis were analyzed by multiple linear regression and binary logistic regression. Results: A total of 185 patients were included in the study. UIE grade showed a significant correlation with age, hydronephrosis grading (HG), ureteroscope placement time (UPT), surgery time (ST), hemoglobin disparity value (HDV), and postoperative ureteral stenosis (PUS) (P < 0.05). Logistics regression analysis showed a gradual increase in intraoperative UPT and ST with increase in UIE grade. The severity of UIE showed a negative correlation with improvement of postoperative hydronephrosis (IPH) and the appearance of PUS. HDV was significantly increased in patients with UIE grade 3. Conclusions: UIE grading can be used as an adjunctive clinical guide for endoscopic treatment of upper urinary tract stones. The postoperative management measures proposed in this study can help inform treatment strategy for ureteral stones.
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CD36 is a transmembrane glycoprotein that binds to a wide range of ligands, including fatty acids (FAs), cholesterol, thrombospondin-1 (TSP-1) and thrombospondin-2 (TSP-2), and plays an important role in lipid metabolism, immune response, and angiogenesis. Recent studies have highlighted the role of CD36 in mediating lipid uptake by tumor-associated immune cells and in promoting tumor cell progression. In cancer-associated fibroblasts (CAFs), CD36 regulates lipid uptake and matrix protein production to promote tumor proliferation. In addition, CD36 can promote tumor cell adhesion to the extracellular matrix (ECM) and induce epithelial mesenchymal transition (EMT). In terms of tumor angiogenesis, CD36 binding to TSP-1 and TSP-2 can both inhibit tumor angiogenesis and promote tumor migration and invasion. CD36 can promote tumor angiogenesis through vascular mimicry (VM). Overall, we found that CD36 exhibits diverse functions in tumors. Here, we summarize the recent research findings highlighting the novel roles of CD36 in the context of tumors.
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Neoplasias , Trombospondina 1 , Humanos , Trombospondina 1/metabolismo , Microambiente Tumoral , Antígenos CD36/metabolismo , Trombospondinas/metabolismo , Neovascularização Patológica , LipídeosRESUMO
2D materials-based nanoelectromechanical resonant systems with high sensitivity can precisely trace quantities of ultra-small mass molecules and therefore are broadly applied in biological analysis, chemical sensing, and physical detection. However, conventional optical and capacitive transconductance schemes struggle to measure high-order mode resonant effectively, which is the scientific key to further achieving higher accuracy and lower noise. In the present study, the different vibrations of monolayer Ti3 C2 Tx MXene piezo-resonators are investigated, and achieve a high-order f2,3 resonant mode with a ≈234.59 ± 0.05 MHz characteristic peak due to the special piezoelectrical structure of the Ti3 C2 Tx MXene layer. The effective measurements of signals have a low thermomechanical motion spectral density (9.66 ± 0.01 fmHz$\frac{{fm}}{{\sqrt {Hz} }}$ ) and an extensive dynamic range (118.49 ± 0.42 dB) with sub-zeptograms resolution (0.22 ± 0.01 zg) at 300 K temperature and 1 atm. Furthermore, the functional groups of the Ti3 C2 Tx MXene with unique adsorption properties enable a high working range ratio of ≈3100 and excellent repeatability. This Ti3 C2 Tx MXene device demonstrates encouraging performance advancements over other nano-resonators and will lead the related engineering applications including high-sensitivity mass detectors.
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Adsorção , TemperaturaRESUMO
As an emerging two-dimensional (2D) material, MXene has excellent conductivity and abundant surface functional groups. Its unique layered structure, large surface area, and prominent hydrophilicity show remarkable performances, which allow abundant possibilities to work as the sensing element alone or combined with other auxiliary materials. As a senior member of MXenes, Ti3C2T x has shown great potential in the development of force sensors. The research development of force sensors based on Ti3C2T x MXene is reviewed in this paper, presenting the advanced development of force sensors in various forms and summaring their current preparation strategies and characteristics. In addition, the corresponding challenges and prospects of the MXene-based sensors are also discussed for future research.
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INTRODUCTION: The analgesic efficacy of magnesium sulphate added to bupivacaine for arthroscopy remains controversial. We conduct a systematic review and meta-analysis to explore the efficacy of magnesium sulphate in combination with bupivacaine for arthroscopy. METHODS: We searched PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through July 2020 for randomized controlled trials (RCTs) assessing the effect of magnesium sulphate plus bupivacaine versus bupivacaine for arthroscopy. This meta-analysis is performed using the random-effect model. RESULTS: Six RCTs were included in the meta-analysis. Overall, compared with bupivacaine for arthroscopy, combination analgesia using magnesium plus bupivacaine was associated with significantly prolonged duration of analgesia (SMD=0.93; 95% CI=0.27 to 1.60; P=0.006) and first time to analgesic requirement (SMD=196.57; 95% CI=13.90 to 379.24; P=0.03), reduced pain scores (SMD=-1.71; 95% CI=-2.96 to -0.46; P=0.007) and analgesic consumption (SMD=-1.04; 95% CI=-1.49 to -0.60; P<0.00001), but showed no remarkable influence on nausea or vomiting (OR=1.54; 95% CI=0.60 to 3.97; P=0.37). CONCLUSIONS: Magnesium sulphate added to bupivacaine may significantly improve the analgesic efficacy for arthroscopy.