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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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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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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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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
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
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
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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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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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.
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Artroscopia , Bupivacaína , Analgésicos/farmacologia , Humanos , Magnésio/química , Sulfato de Magnésio/química , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Overexpression of reactive oxygen species in the substantia nigra pars compacta destroys dopaminergic neurons and accelerates the pathological process of Parkinson's disease (PD). In this study, a new hydrophilic nano-bioconjugate, lactoferrin (Lf)-modified Au-Bi2 Se3 nanodot (ND) for efficient PD therapy is developed. In particular, the Lf-Au-Bi2 Se3 NDs exhibit strong blood-brain barrier (BBB) permeation. The Lf-Au-Bi2 Se3 NDs can also serve as multiple enzymes such as superoxide dismutase, catalase, glutathione peroxidase, and peroxide. These NDs are located close to the mitochondria and thus maintain the mitochondrial membrane potential as well as control the cellular ROS level. In vivo results further demonstrate that the NDs can improve the memory and mobility of PD mice; permeation of the BBB, protection of mitochondria, and suppression of dopaminergic neuron loss in the substantia nigra pars compacta are also observed. It is anticipated that these new Lf-Au-Bi2 Se3 NDs with excellent biocompatibility, multienzyme functionality, and BBB permeability will open new opportunities for PD therapy.
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Doença de Parkinson , Animais , Lactoferrina , Camundongos , Mitocôndrias/metabolismo , Oxigênio , Espécies Reativas de Oxigênio/metabolismoRESUMO
The development of flexible and transparent electromagnetic interference (EMI) shielding materials with excellent comprehensive properties is urgently demanded as visual windows and display devices in aeronautic, industry, medical, and research facilities. However, the method of how to obtain highly efficient and reliable transparent EMI shielding devices is still facing lots of obstacles. Here, a high-performance silver nanotube (AgNT) network with stable and integrated interconnects is prepared by physical depositing technology, based on a uniform and large-scale nanofiber skeleton. This unique structure enables the AgNT network to achieve one order higher conductivity (â¼1.0 Ω/sq at >90% transmittance) than previous research studies and keeps <10% variation with random deformations (>5000 times). Moreover, the manufactured AgNT shielding film with a thickness of less than 1 mm can be easily transferred to arbitrary surfaces as a transparent and flexible EMI shielding film at commercial â¼35 dB EMI shielding effectiveness, with large-scale, low-cost, and simple preparation processes. These excellent properties endow the AgNT shielding film to achieve great potential for future flexible and transparent scenarios.
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People are more likely to make choices themselves than delegate to an agent, even when it may not be the most optimal decision based on a cost-benefit analysis. Previous studies have demonstrated that retaining authority and controllability might be the primary reason for preferring self-choice. The current study asks whether impairment of controllability associated with self-choice can increase the rate of delegation and whether there are self-other discrepancies in self-choice preference. In three studies, we directly manipulated participants' controllability associated with choice through literal instructions (experiment 1) and visual presentation (experiments 2 and 3). We found that participants showed a robust propensity to under-delegate even when they were aware of their impaired controllability associated with self-choice. Moreover, only 40% impairment of controllability (but not 20%) can decrease the propensity to under-delegate. This trend differed between decision-for-self and decision-for-other. These findings suggest that pursuing a sense of control cannot fully explain self-choice preference and appears to occur equally in decisions for oneself as well as for others.
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Tomada de Decisões , Controle Interno-Externo , Comportamento de Escolha , HumanosRESUMO
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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Controllable photonic patterns have attracted great attention for various applications in displays, smart sensors, and communications. Conventional patterned light-emitting-diode (LED) systems require complicated design, complex procedure, and advanced equipment. Moreover, permanent properties of the fabricated patterns on LED restrict it from various important applications. Herein, we present an innovative writable and wipeable perovskite light-emitting-diode (WWPeLED) device, which tactfully utilizes the large variation of turn-on voltage originating from the external quantum efficiency (EQE) difference under controllable thermal treatment. The turn-on voltages with/without thermal-treatment devices exhibit a large gap of over 5 V, and the thermal-treatment electroluminescence intensity is more than 10 times higher than that of non-thermal-treatment devices. The new phenomena open up an effective way of controlling illumination with desired pattern designs. Additionally, the distinct handwriting fonts and habits as well as printing patterns with illumination WWPeLED are also realized. Furthermore, these written and printed features can be totally wiped out with an 11 V cleaning voltage, turning the devices as a regular fully bright PeLED. The stability and repeatability tests prove the robustness of WWPeLED in both mechanical and electroluminescence performance after a long period of operations. The innovative WWPeLED devices may find prospective applications in various optoelectronic devices and flexible integrated systems.
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High-performance photo-triggered electronic devices have already become an abiding target of optoelectronics. Current results, involving high-sensitivity phototransistors with the enhancement of material properties or the modification of electrical field, need an independent external light-source system. Nevertheless, few research studies inform of circuits in which the logic channel can be directly light controlled by a fully integrated photogate. In this paper, nanowire-based photon-effect transistors (PETs) combined with organic light-emitting diode (OLED) gates, and the photo-triggered nanowire circuits (PTNCs) are exhibited. The nanowire channels are manifested as high-quality optical cavities coupled by reflective electrodes for forming standing wave resonance. With the function of resonance, the nanowire channel under the illumination of the OLED gate can reach a high on/off ratio of â¼107, and under the different interconnected configuration of OLED gates, the functions of PETs can separately be realized as P-type and N-type of CMOS-like transistors. Then, a PTNC inverter that includes two nanowire channels with the respective OLED gates is operated utilizing electrical input voltage and logic opposite output signal. NAND and NOR gates as PTNC have also been demonstrated and indicate their corresponding outstanding arithmetic logic operation. PTNCs can effectively represent an innovative step toward multipurpose photonic circuits as to programmable logic components and photo-triggered computing.
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Thin-film resonators and scanning probe microscopies (SPM) are usually used on low-frequency mechanical systems at the nanoscale or larger. Generally, off-chip approaches are applied to detect mechanical vibrations in these systems, but these methods are not much appropriate for atomic-thin-layer devices with ultrahigh characteristic frequencies and ultrathin thickness. Primarily, those mechanical devices based on atomic-layers provide highly improved properties, which are inapproachable with conventional nanoelectromechanical systems (NEMS). In this report, the assembly and manipulation of single-atomic-layer piezo-resonators as mass sensors with eigen mechanical resonances up to gigahertz are described. The resonators utilize electronic vibration transducers based on piezo-electric polarization charges, allowing direct and optimal atomic-layer sensor exports. This direct detection affords practical applications with the previously inapproachable Q-factor and sensitivity rather than photoelectric conversion. Exploration of a 2406.26 MHz membrane vibration is indicated with a thermo-noise-limited mass resolution of â¼3.0 zg (10-21 g) in room temperature. The fabricated mass sensors are contactless and fast and can afford a method for precision measurements of the ultrasmall mass with two-dimentional materials.
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Phototriggered devices have attracted attention due to their exceptional characteristics, advanced multifunctionalities and unprecedented applications in optoelectronic systems. Here, we report a pioneer structural device, a resonant photoeffect-transistor (RPET) with a functionalized nanowire (NW) charge transport channel, modulated by a near-field nanostrip organic light emitting diode (OLED) and controlled by a gate bias to realize exceptional photoelectric properties. The RPET presents high-quality nanowire channel characteristics due to tunable optical cavities manifesting strong standing wave resonance under controlled light emission. To enhance performance, methodical analyses were carried out to determine the effects of the structural design, electric field distribution and charge carrier generation on photoresponsivity when light traverses a single or multiple nanoslit masks. The developed RPET yields stable photocurrents in the 105 range and generates current on/off ratios upward of 106 under the influence of intense electromagnetic distribution, effectively lending itself to promising opportunities in fully integrated optoelectronic devices.
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Among the established findings in eye movement during decision-making, decision-makers are likely to choose the last fixated option, and this phenomenon has proven robust. However, the causal link between last fixation and choices requires further examination. In Study 1 (N = 40), a gaze-contingent manipulation paradigm was developed by controlling the timing of decision prompts to manipulate the last fixation. The results showed that participants' value-based choices were biased toward the last fixated option. However, the manipulation in Study 1 may disturb their decision process, leading to an unnatural decision environment. In Study 2 (N = 40), the gaze-contingent paradigm was further developed to manipulate the last fixation by directing an additional fixation on the target option after the participants' decision prompts. The results showed that participants' choices were also biased in the uninterrupted decisions. Our findings suggest a causal link between last fixation and value-based choices.