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It is still challenging to achieve a complex grasp or fine finger control by using surface functional electrical stimulation (FES), which usually requires a precise electrode configuration under laboratory or clinical settings. The goals of this study are as follows: 1) to study the possibility of selectively activating individual fingers; 2) to investigate whether the current activation threshold and selective range of individual fingers are affected by two factors: changes in the electrode position and forearm rotation (pronation, neutral and supination); and 3) to explore a theoretical model for guidance of the electrode placement used for selective activation of individual fingers. A coordinate system with more than 400 grid points was established over the forearm skin surface. A searching procedure was used to traverse all grid points to identify the stimulation points for finger extension/flexion by applying monophasic stimulation pulses. Some of the stimulation points for finger extension and flexion were selected and tested in their respective two different forearm postures according to the number and the type of the activated fingers and the strength of finger action response to the electrical stimulation at the stimulation point. The activation thresholds and current ranges of the selectively activated finger at each stimulation point were determined by visual analysis. The stimulation points were divided into three groups (\"Low\", \"Medium\" and \"High\") according to the thresholds of the 1st activated fingers. The angles produced by the selectively activated finger within selective current ranges were measured and analyzed. Selective stimulation of extension/flexion is possible for most fingers. Small changes in electrode position and forearm rotation have no significant effect on the threshold amplitude and the current range for the selective activation of most fingers (p > 0.05). The current range is the largest (more than 2 mA) for selective activation of the thumb, followed by those for the index, ring, middle and little fingers. The stimulation points in the \"Low\" group for all five fingers lead to noticeable finger angles at low current intensity, especially for the index, middle, and ring fingers. The slopes of the finger angle variation in the \"Low\" group for digits 2~4 are inversely proportional to the current intensity, whereas the slopes of the finger angle variation in other groups and in all groups for the thumb and little finger are proportional to the current intensity. It is possible to selectively activate the extension/flexion of most fingers by stimulating the forearm muscles. The physiological characteristics of each finger should be considered when placing the negative electrode for selective stimulation of individual fingers. The electrode placement used for the selective activation of individual fingers should not be confined to the location with the lowest activation threshold.

As support agencies of the aviation maintenance and support system, the aviation overhaul depots undertake an important and arduous support mission, which play a pivotal role, so the science and rationality of site selection is extremely significant. This paper choose the nonlinear programming method to build a mathematic model, so as to solve the problem. For the purpose of optimizing and solving the model, a thought based on the improved particle swarm optimization which used in the model is put forward to, and an improved PSO which gained by the analyzing the standard PSO and improving the initial PSO is presented in this paper. Finally, an application example is given to analyze and summarize the model.

To investigate the gearbox radiation noise properties under various rotational speeds, a noise prediction method based on impedance model and noise transfer function (NTF) is proposed. One only needs to extract the NTF of the housing once rapid gearbox noise prediction under different working conditions is realized. Taking a flexible supported gearbox as a research object, the external excitation of the housing (the bearing excitation load and isolator excitation load) is calculated through a gear-housing-foundation-coupled impedance model, and the noise transfer function is simulated through the vibroacoustic-coupled boundary element model; then the radiation noise is obtained. Based on this model, the noise transfer analysis of the housing is carried out, different excitation components and NTF components are compared, and the contributions of different excitation components to noise are compared. Results show that the radiation noise of gearbox is mainly excited by the high-speed bearing, while the low-speed bearing and isolator have little influence on noise. At low speed, vertical force, axial force, and moment excitation of bearings all contribute to the radiation noise while at high speed, the gearbox radiation noise is mainly generated by vertical excitation force of bearings.

Radio amendatory channel is used in command guidance for missile, whose working state has direct influence on the precision of a missile. Therefore, it’s necessary to design a radio frequency detector for cycle detection of radio amendatory channel. After analyzing operating principle of the radio amendatory channel, the paper proposes a detecting program, introduces hardware and software design of radio frequency detector including high frequency receiving module, intermediate frequency receiving module and information processing module. The radio frequency detector has been applied in detecting airborne radio amendatory channel successfully improving support efficiency, and provides a reference for detecting other radio frequency.

In the context of global climate change, a comprehensive understanding of the spatiotemporal impacts of drought on vegetation productivity is essential for assessing terrestrial ecosystem stability. Utilizing outputs from six global climate models (GCMs) from the Coupled Model Intercomparison Project Phase 6 (CMIP6), this study systematically assessed historical and projected drought probability, the drought vulnerability of Net Primary Productivity (NPP), and overall drought risk across the Mongolian Plateau under three Shared Socioeconomic Pathway scenarios (SSP1-2.6, SSP2-4.5, and SSP5-8.5). Results revealed that the Standardized Precipitation Evapotranspiration Index (SPEI) exhibited a declining trend, whereas NPP showed an overall increasing trend. These changes were most pronounced under the SSP5-8.5 scenario, with the SPEI decreasing at a rate of −0.39/10a and NPP increasing at 25.8/10a. Drought severity exhibited strong spatial heterogeneity, intensifying from northeast to southwest, whereas NPP demonstrated an inverse spatial pattern. The spatial distribution of high-drought-risk zones varied markedly across scenarios: the southwestern region was most affected under SSP1-2.6, the northwestern region under SSP2-4.5, and the southeastern region under SSP5-8.5. Based on 12-month SPEI values and NPP derived from the Carnegie–Ames–Stanford Approach (CASA) model, SSP2-4.5 presented the highest overall drought risk, despite lower emissions. The annual mean NPP drought vulnerability ranked as follows: SSP2-4.5 (0.60 gCm−2yr−1) > SSP1-2.6 (−1.03 gCm−2yr−1) > SSP5-8.5 (−1.24 gCm−2yr−1). Projections indicated a substantial increase in drought occurrence probability during the period 2061–2100, particularly under SSP2-4.5 and SSP5-8.5. Under higher emissions, the spatial extent of areas with negative drought vulnerability values was expected to expand 68%. Wind speed was the dominant factor influencing drought risk under SSP1-2.6 and SSP2-4.5, whereas precipitation became the primary driver (45.34%) under SSP5-8.5. These findings offer critical insights for early drought warning systems and for strengthening ecosystem resilience across the Mongolian Plateau.

Developing facile approaches for preparing efficient electrocatalysts is of significance to promote sustainable energy technologies. Here, we report a facile iron-oxidizing bacteria corrosion approach to construct a composite electrocatalyst of nickel–iron oxyhydroxides combined with iron oxides. The obtained electrocatalyst shows improved electrocatalytic activity and stability for oxygen evolution, with an overpotential of ∼230 mV to afford the current density of 10 mA cm−2. The incorporation of iron oxides produced by iron-oxidizing bacteria corrosion optimizes the electronic structure of nickel–iron oxyhydroxide electrodes, which accounts for the decreased free energy of oxygenate generation and the improvement of OER activity. This work demonstrates a natural bacterial corrosion approach for the facile preparation of efficient electrodes for water oxidation, which may provide interesting insights in the multidisciplinary integration of innovative nanomaterials and emerging energy technologies.

Driven by the serious ecological problems, it is urgent to explore high-efficiency sustainable energy technologies. Oxygen electrocatalysis acts as important half-reactions in the emerging electrochemical energy techniques including electrolysis and batteries. Gel composites exhibit the merits of rich porous, superior hydrophilic, and large specific surface area, which can significantly improve the electrolyte penetration and boost the kinetics process of oxygen electrocatalysis. In this invited contribution, the advances and challenges of a novel gel materials for oxygen electrocatalysis are summarized. Starting from the structure—activity—performance relationship of gel materials, synthetic routes of nanostructured gel materials, namely, radical polymerization, sol-gel method, hydrothermal/solvothermal reactions, and ligand-substitution method, are introduced. Afterward, the gel composites are divided into polymer-based, metal-based, and carbon-based materials in turn, and their applications in oxygen electrocatalysis are discussed respectively. At the end, the perspective and challenges for advanced gel oxygen electrocatalysts are proposed.

Piezocatalytic therapy (PCT) based on 2D layered materials has emerged as a promising non‐invasive tumor treatment modality, offering superior advantages. However, a systematic investigation of PCT, particularly the mechanisms underlying the reactive oxygen species (ROS) generation by 2D nanomaterials, is still in its infancy. Here, for the first time, biodegradable piezoelectric 2D bilayer nickel‐iron layered double hydroxide (NiFe‐LDH) nanosheets (thickness of ≈1.86 nm) are reported for enhanced PCT and ferroptosis. Under ultrasound irradiation, the piezoelectric semiconducting NiFe‐LDH exhibits a remarkable ability to generate superoxide anion radicals, due to the formation of a built‐in electric field that facilitates the separation of electrons and holes. Notably, the significant excitonic effect in the ultrathin NiFe‐LDH system enables long‐lived excited triplet excitons (lifetime of ≈5.04 µs) to effectively convert triplet O2 molecules into singlet oxygen. Moreover, NiFe‐LDH exhibited tumor microenvironment (TME)‐responsive peroxidase (POD)‐like and glutathione (GSH)‐depleting capabilities, further enhancing oxidative stress in tumor cells and inducing ferroptosis. To the best of knowledge, this is the first report on piezoelectric semiconducting sonosensitizers based on LDHs for PCT and ferroptosis, providing a comprehensive understanding of the piezocatalysis mechanism and valuable references for the application of LDHs and other 2D materials in cancer therapy. Ultrathin NiFe‐LDH nanosheets with tumor microenvironment‐responsive and GSH‐depletion ability are developed for the first time for enhanced piezocatalytic therapy and ferroptosis. The piezoelectric semiconductor showed outstanding 1O2 generation ability arising from the large excitonic effect in NiFe‐LDH. This study pioneers the development of piezocatalytic tumor therapy in two‐dimension ultrathin LDH materials, effectively inducing the generation of reactive oxygen species.

Compared with other natural fibers, coir fiber has good strength characteristics and long-term anti-biodegradation ability. At present, most studies on randomly distributed coir fiber-reinforced soil have focused on cohesionless soil or granular soil. In this paper, the influence of randomly distributed coir fiber on the deviatoric stress and shear strength index of red clay with different fiber content was assessed by a consolidated undrained (CU) triaxial compression test. Since the hyperbolic variational character of the stress–strain relation of the samples conformed to the hyperbolic hypothesis of the Duncan–Chang model of nonlinear elastic model, the Duncan–Chang model was used to fit it, and the influences of fiber content and confining pressure on the parameters of the Duncan–Chang model were studied. The fiber content was determined by testing to be 0%, 0.2%, 0.25%, 0.3%, 0.35% and 0.4% of the dry soil mass. It has been found that coir fiber distributed in a random radial manner can significantly increase the deviatoric stress of red clay, and thus can be effectively used in the case of soil and fiber mixing. The cohesion of the red clay first increases and then decreases with the increase in fiber content, with an optimum content of 0.3%. The internal friction angle changes little with increasing fiber content.

Glycinin is identified as one of the major dietary allergens in soybean. However, the safety threshold of glycinin in piglets have not been clearly understood. The purpose of this study was to investigate the anti-nutritional effects and sensitization threshold of purified glycinin in weaned piglets. In this experiment, 45 21-day-old weaned castrated piglets (Duroc × Landrace × Yorkshire), with a similar initial body weight of 9.95 ± 0.43 kg, were randomly divided into five groups with nine replicates per group. The piglets in the control group were fed a basal diet, while the piglets in the experimental groups were fed diets containing 1, 2, 3 and 4% purified glycinin, respectively, based on the same basal diet. After determination, the glycine content in the diets of each group was 0.704, 8.779, 16.857, 24.934, and 33.011 mg/g, respectively. Samples of feces, serum, digesta, as well as the segments and mucosa of the small intestine, were collected. The measured parameters included the nutrient apparent metabolic rate, digestive enzyme activities, levels of specific immunoglobulin G, histamine (HIS), and D-lactic acid (D-LA) levels, along with small intestinal morphology. The results showed that, compared to the control group, the average daily gain, the average daily feed intake, and the ratio of weight gain to feed intake of the piglets were linearly and quadratically decreased by the inclusion of 2, 3, and 4% glycinin in the diets ( p  < 0.05). In addition, positive skin sensitization, increased erythema diameter, and elevated specific immunoglobulin G titers were induced by glycinin inclusion ( p  < 0.05). In addition, 2, 3, and 4% glycinin administration led to decreases in the apparent nutrient metabolic ratio and digestive enzyme activities ( p  < 0.05). Moreover, the levels of HIS, diamine oxidase, and D-lactic acid in the small intestine were increased in response to 3 and 4% glycinin supplementation ( p  < 0.05). In addition, the reduced D-xylose concentration and damaged intestinal morphology in the piglets observed were induced by the inclusion of 2, 3, and 4% glycinin ( p  < 0.05). The above results indicate that glycinin inclusion at doses above 1% can trigger allergenic effects, including increased erythema diameter, elevated specific immunoglobulin G titers, and higher levels of HIS and D-lactic acid. In contrast, glycinin inclusion at doses above 2% can induce some anti-nutrition effects, such as decreased apparent nutrient metabolic ratio, reduced digestive enzyme activities, and damaged small intestinal morphology. In addition, the information mentioned above implied that the sensitization threshold of glycinin administration in the piglets was 8.779 mg/g and the anti-nutrition threshold was 16.857 mg/g.