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Sensitive high‐energy photon detection from UV to X‐ray and high‐resolution array imaging are critical for medical diagnosis, space exploration, and scientific research. The key challenges for high‐performance photodetector and imaging arrays are the effective material and device design strategies for the miniaturization and integration of the device. Here, photon‐controlled diodes (i.e., the detector has rectifying characteristics only under light irradiation) are proposed for high‐resolution and anti‐crosstalk array imaging applications without integrating the switching element. Based on ultra‐wide bandgap semiconductor Ga2O3, the sensitive DUV/X‐ray photon‐controlled diodes are realized by the design of high‐resistance Ga2O3 film and high‐barrier contact. The device exhibits remarkable detection performance, including high photo‐responsivity (168 A W−1) and specific detectivity (1.45 × 1015 Jones) under DUV illumination, as well as a high sensitivity (1.23 × 105 µC Gyair−1 cm−2) under X‐ray light. Moreover, the low dark current and excellent rectification characteristics are obtained. Furthermore, its potential for high‐density and anti‐crosstalk array imaging applications is verified. These results not only bring forth new insights in the implementation of high‐performance DUV/X‐ray photodetector, but also pave a feasible way to realize high pixel density detector array through the simplified fabrication process for high‐resolution imaging applications. [ABSTRACT FROM AUTHOR]

Thyroid cancer is the most common type of endocrine cancer, and most patients have a good prognosis. However, the thyroid cancer differentiation status strongly affects patient response to conventional treatment and prognosis. Therefore, exploring the molecular mechanisms that influence the differentiation of thyroid cancer is very important for understanding the progression of this disease and improving therapeutic options. In this study, SETMAR as a key gene that affects thyroid cancer differentiation is identified. SETMAR significantly regulates the proliferation, epithelial‐mesenchymal transformation (EMT), thyroid differentiation‐related gene expression, radioactive iodine uptake, and sensitivity to MAPK inhibitor‐based redifferentiation therapies of thyroid cancer cells. Mechanistically, SETMAR methylates dimethylated H3K36 in the SMARCA2 promoter region to promote SMARCA2 transcription. SMARCA2 can bind to enhancers of the thyroid differentiation transcription factors (TTFs) PAX8, and FOXE1 to promote their expression by enhancing chromatin accessibility. Moreover, METTL3‐mediated m6A methylation of SETAMR mRNA is observed and showed that this medication can affect SETMAR expression in an IGF2BP3‐dependent manner. Finally, the METTL3‐14‐WTAP activator effectively facilitates the redifferentiation of thyroid cancer cells via the SETMAR‐SMARCA2‐TTF axis utilized. The research provides novel insights into the molecular mechanisms underlying thyroid cancer dedifferentiation and provides a new approach for therapeutically promoting redifferentiation. [ABSTRACT FROM AUTHOR]

Gallium oxide (Ga2O3), with an ultrawide bandgap corresponding to the deep ultraviolet (DUV) range, has attracted significant attention in optical filter‐free photodetectors. In practical terms, DUV photodetectors employed in extreme conditions, for example, flame detection and space exploration, face the challenges of performance degradation caused by high/low‐temperature transformation. Here, DUV photodetectors are tailored with high durability and stability by one‐step‐grown β‐Ga2O3 films via pulsed laser deposition. A high‐oxygen‐pressure scheme effectively addresses the issue of film‐free deposition at specifically high temperatures, facilitating the formation of polycrystalline high‐resistivity β‐Ga2O3 films. As a result, the devices exhibit outstanding performance, including a low dark current (4.4 pA @30 V), high photoresponsivity (147.36 A W−1), and fast response time (3.1/22.6 ms). Additionally, the photoresponse performance shows minimal degradation at high temperatures up to 300 °C and even improves at low temperatures down to −100 °C, ranking it among the most robust DUV photodetectors. The mechanism of photoresponse, involving the exciton formation, bandgap evolution, carrier‐phonon scatter, etc., is also elucidated in a wide temperature range. This work provides an efficient solution for developing robust Ga2O3 DUV photodetectors with excellent performance for extreme‐condition applications. [ABSTRACT FROM AUTHOR]

Ga2O3 photodetectors with demonstrated high sensitivity provide a potential subversive scheme for solar‐blind photodetection. However, the planar structure and the relatively slow response speed of the device have restricted the integration and application of Ga2O3 photodetectors. Herein, a narrow SiO2 barrier layer is introduced on the commercial SiC substrate, and a vertical photodetector is realized based on β‐Ga2O3/SiO2/SiC heterostructure with controllable tunneling effect by tailoring the band structure at the interface. The developed device exhibits unconventional rectification characteristics and photoresponse performance in different biasing modes owing to the controllable tunneling effect at the interface. In particular, the photodetector achieves a high responsivity (186.8 A W−1) under solar‐blind illumination at reverse bias, while exhibiting obvious advantages in dark current (3 pA), photo‐to‐dark current ratio (8.8 × 106), linear dynamic range (138.8 dB), and specific detectivity (1.4 × 1015 Jones) at forward bias. The photodetector also demonstrates excellent photoresponse stability after 6 months in air without encapsulation. In addition, an alternating biasing strategy, inspired by its bidirectional operability, is proposed to suppress the persistent photoconductivity effect and increase the decay speed by 1.23 × 105 times. This work provides a referable strategy for the further development of high‐performance Ga2O3‐based photoelectronics. [ABSTRACT FROM AUTHOR]

Pore‐fracture structure distribution heterogeneity (PFSH) affects dynamic variation of porosity‐permeability of tight sandstone reservoirs, then restricting gas production performance. A fractal model by low‐field nuclear magnetic resonance technology (LF‐NMR) has been used in the quantitative characterization of PFSH. Among some literature, PFSH was studied by using a saturated T2 spectrum. However, there are few studies on fractal characteristics of T2 spectral morphology in a centrifugal state and its influence on porosity‐permeability parameters. In this paper, 30 tight sandstone samples were collected from Taiyuan Formation in Qinshui Basin. Then LF‐NMR technology was used to analyze PFSH, and sample types were divided by using T2 spectra difference under saturated and centrifugal conditions. Meanwhile, single (model 1 and 2) and multi‐fractal model are adopted to calculate fractal parameters of saturated and centrifugal T2 spectra, and then a difference in fractal parameters under different water conditions was compared. Correlation between different fractal parameters, pore structure and T2 cut‐off value are studied, and a mathematical prediction model for T2 cut‐off value by using fractal and pore structure parameters are established. The results are as follows. (1) All the samples are divided into four types A/B/C/D. For example, the type A sample is characterized by a single peak of T2 spectrum and T2 value is less than 10 ms, which indicates that this type belongs a smaller‐pore developed. Type B sample is characterized by a single peak of T2 spectrum and T2 value is10–100 ms, which indicates that this type belongs to mesopore developed. (2) In saturated state (DS), PFSH of type A sample by using model 1 and 2 is stronger than that of type B, followed by type C and D. Then the multifractal model shows that PFSH of type B sample is stronger than that of other sample types. Correlation between fractal dimension calculated by using single fractal and pore structure parameters is stronger than that of multifractal dimension. (3) T2 spectrum in centrifugal state has fractal characteristics (Di), and there are certain correlation Di with Ds. Therefore, a mathematical prediction model for T2 cut‐off value by using fractal and pore structure parameters is established. © 2023 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

High deep‐ultraviolet (DUV) sensitivity and excellent flexibility of ultrathin gallium oxide (Ga2O3) film with an ultrawide bandgap endow its extreme propensity in flexible DUV photodetector especially for space exploration and wearable electronics. However, an efficient strategy with high throughput and low cost is highly deficient to realize flexible and robust Ga2O3 DUV photodetectors to face potential harsh environments. In this work, flexible and heat‐resistant Ga2O3 DUV photodetectors based on optimized inkjet printing with environmental‐friendly aqueous solvent are demonstrated. The dynamic evolution from Ga(NO3)3 precursor to crystalline Ga2O3 film has been explicitly uncovered. Photodetectors based on printed ultrathin Ga2O3 films on rigid substrate exhibit outstanding performance, including high photo‐to‐dark current ratio about 106, considerable responsivity of 1.3 A W−1, superior detectivity of 1.46 × 1014 Jones, and fast decay time of 0.026 s under 254 nm illumination. In addition, flexible devices on mica substrate not only retain outstanding photoelectrical performance, but also demonstrate excellent mechanical flexibility and thermal stability. Moreover, benefiting from the uniformity of the pixels by high‐throughput inkjet printing, the Ga2O3 DUV photodetector array presents excellent sharp‐imaging capability. This work provides a feasible strategy for printable, flexible, and harsh‐environment‐resistant Ga2O3 DUV photodetectors toward space exploration and wearable electronics. [ABSTRACT FROM AUTHOR]

In recent years, spiking neural networks (SNNs), which originated from the theoretical basis of neuroscience, have attracted neuromorphic computing and brain‐like computing due to their advantages, such as neural dynamics and coding mechanism, which are similar to biological neurons. SNNs have become one of the mainstream frameworks in the field of brain‐like computing. However, most of the Leaky Integrate‐and‐Fire (LIF) neuron models currently used by SNNs based on direct training of backpropagation (BP) do not consider the changes in the recurrent connections and the dynamic strength of neuron connections over time. This study presented the LIF neuron model with recurrent connections and a method for dynamically changing the presynaptic currents. Recurrent LIF neurons have an additional cyclic connection compared with classic LIF neurons. Their postsynaptic current stimulates a change in membrane potential at the next time point. Their dynamics were more similar to the activities of biological neurons. We also proposed an efficient and flexible BP training method for recurrent LIF neurons. On the basis of the above methods, we proposed the recurrent SNN with dynamic presynaptic currents based on backpropagation (RDS‐BP). We test the proposed RDS‐BP on three image data sets (MNIST, Fashion‐MNIST and CIFAR‐10) and two text data sets (IMDB and TREC). The results showed that the performance of RDS‐BP not only exceeded the naive SNN models based on BP but also exceeded the SNN methods proposed in previous studies in recent years, which had excellent performance in previous experiments. Our work provides a new LIF neuron model with a recurrent connection and dynamic presynaptic current and a BP training arrangement for the proposed neuron, which could merit developments with neuromorphic and brain‐like computing. [ABSTRACT FROM AUTHOR]

Self‐powered solar‐blind photodiodes with convenient operation, easy fabrication, and weak‐light sensitivity, are highly desired in environmental monitoring and deep space exploration. Ga2O3 with its bandgap directly corresponding to solar‐blind waveband is a promising candidate material for solar‐blind photodetection. However, ever‐reported self‐powered Ga2O3 photodiodes suffer unsatisfactory photoresponse performance, owing to unideal interface and electrode transmittance. Here, Ag nanowire (AgNW) networks with excellent solar‐blind ultraviolet transmittance are introduced to form self‐powered AgNW–Ga2O3 photodiodes with sharp Schottky interfaces. The tradeoff between solar‐blind ultraviolet transmittance and carrier‐collection ability of the sparse AgNW network is systematically studied and the AgNW density is optimized for the best photoresponse. Expansion of depletion region outwards the AgNW–Ga2O3 contact and the field crowding effect facilitate the high photoresponse. As a result, the champion AgNW–Ga2O3 Schottky photodiode exhibits excellent sensitivity for weak‐light detection, including considerable responsivity of 14.8 mA W–1, ultrahigh photo‐to‐dark‐current ratio above 1.2 × 105, high rejection ratio (R254 nm/R365 nm) of 2.6 × 103, and fast response speed (rise/decay time of 20/24 ms) under self‐powered mode. Balancing the transmittance and carrier‐collection ability of elaborate electrode provides an alternative strategy to achieve high‐performance self‐powered Ga2O3 photodetectors for future weak‐light‐sensitive optoelectronic systems. [ABSTRACT FROM AUTHOR]

Solution‐processed indium‐gallium‐zinc oxide (IGZO) thin film transistors (TFTs) have become well known in recent decades for their promising commercial potential. However, the unsatisfactory performance of small‐sized IGZO TFTs is limiting their applicability. To address this issue, this work introduces an interface engineering method of bi‐functional acid modification to regulate the interfaces between electrodes and the channels of IGZO TFTs. This method increases the interface oxygen vacancy concentration and reduces the surface roughness, resulting in higher mobility and enhanced contact at the interfaces. The TFT devices thus treated display contact resistance reduction from 9.1 to 2.3 kΩmm, as measured by the gated four‐probe method, as well as field‐effect mobility increase from 1.5 to 4.5 cm2 (V s)−1. Additionally, a 12 × 12 organic light emitting diode display constructed using the acid modified IGZO TFTs as switching and driving elements demonstrate the applicability of these devices. [ABSTRACT FROM AUTHOR]

Monoclinic beta‐phase gallium oxide (β‐Ga2O3) is an ultrawide‐bandgap semiconductor, intensively studied as a viable candidate for next‐generation power electronics, optoelectronics, and extreme environment electronics. Schottky contacts to β‐Ga2O3 are of paramount importance to this end; however, they are not yet fundamentally understood. Intrinsic sources of interfacial disorder, including oxygen‐related defects and extrinsic fabrication factors, are thought to greatly determine the properties of such contacts, for example by originating Fermi level pinning and causing patches with different Schottky barrier heights (SBHs). Ballistic electron emission microscopy (BEEM) is used to probe band bending and interfacial inhomogeneity at the nanoscale for prototypical Au/ and Pt/(100)β‐Ga2O3 single crystal Schottky barrier diodes. It is shown that SBH fluctuations amount to 40–60 meV under vacuum, occurring over length scales of tens of nanometers. Furthermore, a remarkable SBH modulation of ≈0.2 eV takes place upon exposure of devices from vacuum to ambient air. Such findings—better obtained by BEEM than by macroscale approaches—point to the existence of an ubiquitous inhomogeneous interfacial layer, controlling band bending and ambient sensitivity via oxygen ionosorption and interface redox chemistry. This study ascribes a key role to interfacial oxygen vacancies, and has practical implications for transport modelling and interface engineering. [ABSTRACT FROM AUTHOR]

Herein, high‐performance enhancement‐mode (E‐mode) β‐Ga2O3 metal‐oxide‐semiconductor field‐effect transistors (MOSFETs) are achieved on Si‐doped homoepitaxial films. Oxygen annealing (OA) treatment under the gate region is used to effectively exhaust the channel electron, resulting in the normally off operation of the device. The threshold voltage, defined as that at the drain current of 0.1 mA mm−1, for the fabricated device is extracted to be 4.1 V. Moreover, double source‐connected field plates are used to suppress the peak electric fields in both Ga2O3 channel and SiNx passivation layer. The fabricated β‐Ga2O3 MOSFETs with gate‐to‐drain distance (Lgd) of 17 μm exhibit a record high breakdown voltage over 3000 V. It is shown that the OA treatment is a new way to obtain high‐performance E‐mode β‐Ga2O3 power MOSFETs. [ABSTRACT FROM AUTHOR]

Abstract: Charge transport governs the operation and performance of organic diodes. Illuminating the charge‐transfer/transport processes across the interfaces and the bulk organic semiconductors is at the focus of intensive investigations. Traditionally, the charge transport properties of organic diodes are usually characterized by probing the current–voltage (I–V) curves of the devices. However, to unveil the landscape of the underlying potential/charge distribution, which essentially determines the I–V characteristics, still represents a major challenge. Here, the electrical potential distribution in planar organic diodes is investigated by using the scanning Kelvin probe force microscopy technique, a method that can clearly separate the contact and bulk regimes of charge transport. Interestingly, by applying to devices based on novel, high mobility organic materials, the space‐charge‐limited‐current‐like I–V curves, which are previously believed to be a result of the bulk transport, are surprisingly but unambiguously demonstrated to be caused by contact‐limited conduction. A model accounting is developed for the transport properties of both the two metal/organic interfaces and the bulk. The results indicate that pure interface‐dominated transport can indeed give rise to I–V curves similar to those caused by bulk transport. These findings provide a new insight into the charge injection and transport processes in organic diodes. [ABSTRACT FROM AUTHOR]

Background Psychophysical and behavioral studies have demonstrated that perception of motion can be impaired by acute alcohol exposure. The neural activities of posteromedial lateral suprasylvian cortex ( PMLS) of cats are directly linked to the perception of visual motion speed. To date, there have been no studies on the effects of acute alcohol exposure in vivo upon the representation of speed in PMLS neurons. Methods Alcohol was administered intravenously as a 20% (v/v) saline solution via a syringe at a dose levels of 0.5, 1, or 2 g/kg to generate a series of blood alcohol concentrations. Using extracellular single-unit recording technique, we recorded the speed-tuning properties of PMLS neurons that responded to random-dot patterns before and after alcohol administration, and simultaneously monitored the concentration of ethanol by detecting the breath alcohol concentration using a breath analyzer. Results After acute alcohol treatment, PMLS cells preferred lower speeds. A broadened speed-tuning bandwidth of PMLS cells was also observed after acute alcohol administration. Additionally, response modulation and discriminative capacity for speed of visual motion in the PMLS cells were significantly impaired after acute alcohol exposure. Concurrently, PMLS cells after acute alcohol exposure showed decreased spontaneous activity, peak responses, and signal-to-noise ratios. Conclusions There is a significant functional degradation in the neural representation of visual motion speed in PMLS of cats after acute alcohol exposure. These neural changes may contribute to the alcohol-related deficits in visual motion perception observed in behavioral studies. [ABSTRACT FROM AUTHOR]

Sensor nodes in sensor networks often gather data and deliver them to the sink. However, the energy and radio range constraints force them to cooperate in transmitting the data to the destination with multihop communication. To achieve this, nodes have to be clustered and some of them are elected as the cluster head nodes to transmit the aggregated data. Unfortunately, the clustering brings extra traffic load to the cluster head nodes, particularly those closer to the sink. These nodes die faster than before as their energy is drained at a high rate. Therefore, some clustering and cluster head election algorithms were suggested to use the unequal clustering size to extend the lifetime of cluster head nodes. However, it is difficult to obtain the accurate cluster size in the process of unequal clustering. Moreover, some cluster head nodes with the overfull cluster members may die early. We propose an enhanced unequal clustering size algorithm to optimize the unequal cluster size in the different layers and balance the dissipation energy of all cluster head nodes. Simulation results show that our algorithm dissipates approximately the same energy of cluster head nodes in the different layers per round and obviously increases the number of rounds of data gathering and transmission. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

High breakdown voltage and exceptional robustness make β‐Ga2O3 power devices a key focus of current research. Despite growing attention to the reliability of β‐Ga2O3 devices, systematic studies are still limited, and comparative analyses between different structures remain unreported. This study presents a comparative analysis of β‐Ga2O3 Schottky barrier diodes (SBD) and p‐NiO/β‐Ga2O3 heterojunction diodes (HJD) with mesa termination through comprehensive reliability test, including high‐temperature storage, reverse recovery, surge current, and rectification characteristics. The results indicate that the SBDs outperform in high‐frequency rectification performance up to 1 MHz, whereas the HJDs demonstrate superior high‐temperature stability of 250 °C. The surge current densities of the SBD and HJD devices reach 0.88 and 0.78 kA cm−2, respectively, representing the highest values reported to date. In particular, the efficiency of both the SBD and HJD devices exceeds 95% in circuit application, with SBD excelling in high‐frequency mode and HJD performing optimally in high‐temperature conditions. This study highlights the high reliability of β‐Ga2O3 devices and provides valuable insights for the application under varied operating conditions. [ABSTRACT FROM AUTHOR]