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Exploitation of the oxidation behaviour in an environmentally sensitive semiconductor is significant to modulate its electronic properties and develop unique applications. Here, we demonstrate a native oxidation-inspired InSe field-effect transistor as an artificial synapse in device level that benefits from the boosted charge trapping under ambient conditions. A thin InO x layer is confirmed under the InSe channel, which can serve as an effective charge trapping layer for information storage. The dynamic characteristic measurement is further performed to reveal the corresponding uniform charge trapping and releasing process, which coincides with its surface-effect-governed carrier fluctuations. As a result, the oxide-decorated InSe device exhibits nonvolatile memory characteristics with flexible programming/erasing operations. Furthermore, an InSe-based artificial synapse is implemented to emulate the essential synaptic functions. The pattern recognition capability of the designed artificial neural network is believed to provide an excellent paradigm for ultra-sensitive van der Waals materials to develop electric-modulated neuromorphic computation architectures. Developing efficient memory and artificial synaptic systems based on environmentally sensitive van der Waals materials remains a challenge. Here, the authors present a native oxidation-inspired InSe field-effect transistor that benefits from a boosted charge trapping behavior under ambient conditions.

Reconfigurable field-effect transistors (FETs) combine unipolar n- and p-type characteristics in a single programmable device and could be used to reduce the complexity of electronic devices. However, current reconfigurable FETs require a constant voltage supply to achieve polarity conversion, leading to high power consumption. Here we report a reconfigurable FET that is based on a hexagonal boron nitride/rhenium diselenide/hexagonal boron nitride (hBN/ReSe 2 /hBN) heterostructure and has a nonvolatile and tunable polarity. A photoinduced trapping mechanism is used to drive photoexcited holes or electrons into the interface between the hBN and the silicon dioxide substrate. The reconfigurable FET can switch between a transistor and memory mode, and several FETs can be used to create inverter, AND, OR, NAND, NOR, XOR and XNOR circuits. We also show that, when in memory-mode operation, the devices can be used to emulate synaptic functions for neuromorphic computing systems. A reconfigurable field-effect transistor based on a hexagonal boron nitride/rhenium diselenide/hexagonal boron nitride heterostructure can offer nonvolatile control of its channel conductivity via photoinduced trapping of electrons or holes at the bottom dielectric interface.

Temporal Interference Stimulation (TIS) represents a novel non-invasive brain stimulation technique that deeply targets specific brain regions using the differential beat frequency of two high-frequency stimulation pairs. This study investigated the neuromodulatory effects of TIS at different beat frequencies on cortical excitability in the rat motor cortex. Rats were randomly assigned into four groups, receiving TIS at alpha (10 Hz), beta (20 Hz), gamma (70 Hz), or sham frequencies targeting the motor cortex for 20 min under anesthesia. Cortical excitability and inhibition were evaluated by measuring motor-evoked potentials (MEPs), input-output (I/O) curves, and long-interval intracortical inhibition (LICI) before and after TIS. Additionally, immunohistochemistry was performed for neural biomarkers c-Fos and glutamic acid decarboxylase (GAD-65) to confirm targeted neural activation following TIS. We also examined glial fibrillary acidic protein (GFAP)-positive cells in the stimulated region to assess astrocyte responses associated with TIS. Alpha and gamma TIS significantly increased MEP amplitudes compared to sham stimulation. The analysis of I/O curves revealed a significant enhancement in the area under the curve (AUC) post-stimulation in the alpha and gamma TIS groups. Notably, only gamma TIS significantly reduced intracortical inhibition, indicated by an increased LICI ratio post-stimulation. Immunohistochemical analysis demonstrated a significant 35% increase in c-Fos-positive cells in the stimulated motor cortex regions after TIS compared to sham, whereas no significant changes in GAD-65-positive cells or GFAP expression were observed. These findings indicate that a single session of alpha or gamma TIS effectively modulates cortical excitability, highlighting its potential for targeted neuromodulation applications.

This paper investigates the influence of C2H2 flow rates on the optical properties, surface roughness, and residual stress of Ti/WC thin films deposited on glass substrates. A range of Ti/WC thin films with varying carbon contents were prepared using the reactive pulsed DC magnetron sputtering technique. The properties of the Ti/WC films can be tuned by adjusting the deposition parameters, among which the acetylene (C2H2) flow rate plays a key role in determining the thin film’s microstructure, optical properties, and stress behavior. The optical properties of the thin films were analyzed using UV-visible-NIR spectroscopy and Fourier transform infrared (FTIR) spectroscopy, the surface morphology was analyzed using microscopic interferometry, and the residual stress in the films was measured using a homemade Twyman–Green interferometer. The measurement results show that the average reflectance of Ti/WC films decreases with the increase in the C2H2 flow rate, and the measured value changes from 52.24% to 44.56% in the wavelength of 400–800 nm. The infrared reflectance of Ti/WC films in the wavelength of 2.5–25 μm is 81.8% for 10 sccm, 80.8% for 20 sccm, 77.2% for 30 sccm, and 73.6% for 40 sccm. The tensile stress of the Ti/WC films deposited on B270 substrates increases with the increase in the C2H2 flow rate, and the stress value changes from 0.361 GPa to 0.405 GPa. The surface roughness of Ti/WC films initially increases and then decreases slightly with the increase in the C2H2 flow rate. These results indicate that the C2H2 flow ratio significantly affects the reflectance in the visible and infrared bands, surface roughness, and residual stress of the Ti/WC films, which is of great significance for optimizing thin film performance to meet specific application requirements.

In this paper, the forked-web joint configuration was introduced first, in order to transfer the shear and moment forces better and avoid the local buckling problem that usually happens in narrow steel beams and concrete-filled steel tubular (CFST) column joints. Experiments including three specimens of that joint were then conducted, considering different axial compression ratios of the column. The test results indicated that no failure phenomenon happened to the proposed joint when the equivalent rotational angle was no more than 1/50. However, the final failure mode of each specimen was still local buckling and tearing failure of beam flanges due to the excessively large stress. Finally, based on the tests and FEA results, a corresponding improvement, including a single-web configuration with U-shape and triangular stiffeners, was thus brought forward and numerically verified in terms of rotational stiffness, failure mode, and the hysteretic curve. The FEA results revealed that the rotational stiffness of the proposed single-web joint with triangular stiffeners for beams and U-shape stiffeners for CFST columns efficiently increased from 0.87 to 3.83, and it was almost twice that of the narrow beam-column joint with internal horizontal diaphragms. Moreover, the previous undesirable tearing failure mode was finally avoided by adopting high-strength steel Q550 for the joint beam part.

Repetitive transcranial magnetic stimulation (rTMS) is a popular noninvasive technique for modulating motor cortical plasticity and has therapeutic potential for the treatment of Parkinson’s disease (PD). However, the therapeutic benefits and related mechanisms of rTMS in PD are still uncertain. Accordingly, preclinical animal research is helpful for enabling translational research to explore an effective therapeutic strategy and for better understanding the underlying mechanisms. Therefore, the current study was designed to identify the therapeutic effects of rTMS on hemiparkinsonian rats. A hemiparkinsonian rat model, induced by unilateral injection of 6-hydroxydopamine (6-OHDA), was applied to evaluate the therapeutic potential of rTMS in motor functions and neuroprotective effect of dopaminergic neurons. Following early and long-term rTMS intervention with an intermittent theta burst stimulation (iTBS) paradigm (starting 24 h post-6-OHDA lesion, 1 session/day, 7 days/week, for a total of 4 weeks) in awake hemiparkinsonian rats, the effects of rTMS on the performance in detailed functional behavioral tests, including video-based gait analysis, the bar test for akinesia, apomorphine-induced rotational analysis, and tests of the degeneration level of dopaminergic neurons, were identified. We found that four weeks of rTMS intervention significantly reduced the aggravation of PD-related symptoms post-6-OHDA lesion. Immunohistochemically, the results showed that tyrosine hydroxylase- (TH-) positive neurons in the substantia nigra pars compacta (SNpc) and fibers in the striatum were significantly preserved in the rTMS treatment group. These findings suggest that early and long-term rTMS with the iTBS paradigm exerts neuroprotective effects and mitigates motor impairments in a hemiparkinsonian rat model. These results further highlight the potential therapeutic effects of rTMS and confirm that long-term rTMS treatment might have clinical relevance and usefulness as an additional treatment approach in individuals with PD.

Transcranial Burst Electrical Stimulation (tBES) is an innovative non-invasive brain stimulation technique that combines direct current (DC) and theta burst stimulation (TBS) for brain neuromodulation. It has been suggested that the tBES protocol may efficiently induce neuroplasticity. However, few studies have systematically tested neuromodulatory effects and underlying neurophysiological mechanisms by manipulating the polarity of DC and TBS patterns. This study aimed to develop the platform and assess neuromodulatory effects and neuronal activity changes following tBES. Five groups of rats were exposed to anodal DC combined with intermittent TBS (tBES+), cathodal DC combined with continuous TBS (tBES-), anodal and cathodal transcranial direct current stimulation (tDCS+ and tDCS-), and sham groups. The neuromodulatory effects of each stimulation on motor cortical excitability were analyzed by motor-evoked potentials (MEPs) changes. We also investigated the effects of tBES on both excitatory and inhibitory neural biomarkers. We specifically examined c-Fos and glutamic acid decarboxylase (GAD-65) using immunohistochemistry staining techniques. Additionally, we evaluated the safety of tBES by analyzing glial fibrillary acidic protein (GFAP) expression. Our findings demonstrated significant impacts of tBES on motor cortical excitability up to 30 min post-stimulation. Specifically, MEPs significantly increased after tBES (+) compared to pre-stimulation (  = 0.026) and sham condition (  = 0.025). Conversely, tBES (-) led to a notable decrease in MEPs relative to baseline (  = 0.04) and sham condition (  = 0.048). Although tBES showed a more favorable neuromodulatory effect than tDCS, statistical analysis revealed no significant differences between these two groups (  > 0.05). Additionally, tBES (+) exhibited a significant activation of excitatory neurons, indicated by increased c-Fos expression (  < 0.05), and a reduction in GAD-65 density (p < 0.05). tBES (-) promoted GAD-65 expression (  < 0.05) while inhibiting c-Fos activation (  < 0.05), suggesting the involvement of cortical inhibition with tBES (-). The expression of GFAP showed no significant difference between tBES and sham conditions (  > 0.05), indicating that tBES did not induce neural injury in the stimulated regions. Our study indicates that tBES effectively modulates motor cortical excitability. This research significantly contributes to a better understanding of the neuromodulatory effects of tBES, and could provide valuable evidence for its potential clinical applications in treating neurological disorders.

Background: Parkinson’s disease (PD) is the second most common neurodegenerative disorder among the elderly. Although pharmacological therapies can alleviate symptoms, they often fail to provide sustained or complete symptom control, underscoring the need for alternative therapeutic strategies. Neuromodulation techniques, particularly cortical electrical stimulation (CES), have shown promise in modulating cortical plasticity. However, the therapeutic efficacy of CES in PD remains to be fully elucidated. In this study we investigated the long-term therapeutic potential of a novel CES protocol in a transgenic MitoPark mouse model of PD. Methods: MitoPark mice received CES beginning at 8 weeks of age (one session per day, 2 days per week) for a total of 12 weeks. Motor function was assessed using a comprehensive behavioral battery, including beam walking, open-field, and gait performance tests. Neuroprotective effects were evaluated by quantifying dopaminergic neuronal survival and striatal fiber density using tyrosine hydroxylase (TH) immunohistochemistry. Results: Long-term CES treatment significantly ameliorated motor impairments in MitoPark mice, improving locomotor activity, gait coordination, and beam walking performance compared with sham controls. Immunohistochemical analyses further revealed enhanced survival of nigrostriatal dopaminergic neurons and fibers in the CES-treated group, indicating pronounced neuroprotective effects. Conclusions: These findings demonstrate that early and sustained CES intervention mitigates motor deficits and enhances dopaminergic neuron survival in the MitoPark PD model. The results provide compelling preclinical evidence supporting CES as a potential adjunctive neuromodulatory therapy for Parkinson’s disease.

Foot drop is a common clinical gait impairment characterized by the inability to raise the foot or toes during walking due to the weakness of dorsiflexors of the foot. Lumbar spine disorders are common neurogenic causes of foot drop. The accurate prognosis and treatment protocols of foot drop are not well delineated in the scientific literature due to the heterogeneity of the underlying lumbar spine disorders, different severities and distinct definitions of the disease. For translational purposes, the use of animal disease models could be the best way to investigate the pathogenesis of foot drop and help develop effective therapeutic strategies for foot drops. However, no relevant and reproducible foot drop animal models with a suitable gait analysis method were developed for the observation of foot drop symptoms. Therefore, the present study aimed to develop a ventral root avulsion (VRA)-induced foot drop rat model and record detailed time-course changes of gait pattern following L5, L6 or L5 + L6 VRA surgery. Our results suggested that L5 + L6 VRA rats exhibited changes in gait patterns, as compared to sham lesion rats, including a significant reduction of walking speed, step length, toe spread and swing phase time, as well as an increased duration of the stance phase time. The ankle kinematic data exhibited that the ankle joint angle increased during the mid-swing stage, indicating a significant foot drop pattern during locomotion. Time-course observations displayed that these gait impairments occurred as early as the first-day post-lesion and gradually recovered 7 to 14 days post-injury. We conclude that the proposed foot drop rat model with a video-based gait analysis approach can precisely detect the foot drop pattern induced by VRA in rats, which can provide insight into the compensatory changes and recovery in gait patterns and might be useful for serving as a translational platform bridging human and animal studies for developing novel therapeutic strategies for foot drop.

Van der Waals (vdW) heterostructures—in which layered materials are purposely selected to assemble with each other—allow unusual properties and different phenomena to be combined and multifunctional electronics to be created, opening a new chapter for the spread of internet‐of‐things applications. Here, an O2‐ultrasensitive MoTe2 material and an O2‐insensitive SnS2 material are integrated to form a vdW heterostructure, allowing the realization of charge‐polarity control for multioperation‐mode transistors through a simple and effective rapid thermal annealing strategy under dry‐air and vacuum conditions. The charge‐polarity control (i.e., doping and de‐doping processes), which arises owing to the interaction between O2 adsorption/desorption and tellurium defects at the MoTe2 surface, means that the MoTe2/SnS2 heterostructure transistors can reversibly change between unipolar, ambipolar, and anti‐ambipolar transfer characteristics. Based on the dynamic control of the charge‐polarity properties, an inverter, output polarity controllable amplifier, p‐n diode, and ternary‐state logics (NMIN and NMAX gates) are demonstrated, which inspire the development of reversibly multifunctional devices and indicates the potential of 2D materials. Although various van der Waals stacking systems for preparing multifunctional devices are reported, their complexity in fabrication and/or inflexibility in reversible operation limit the possibility of multifunctional integrations and the requirement of the fast‐growing internet of things paradigm. Here, a simple and effective rapid temperature annealing strategy for reversibly controlling and optimizing the electronic properties of MoTe2‐based heterostructure electronics is proposed/realized.