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Surface electromyography (sEMG) offers a novel method in human–machine interactions (HMIs) since it is a distinct physiological electrical signal that conceals human movement intention and muscle information. Unfortunately, the nonlinear and non-smooth features of sEMG signals often make joint angle estimation difficult. This paper proposes a joint angle prediction model for the continuous estimation of wrist motion angle changes based on sEMG signals. The proposed model combines a temporal convolutional network (TCN) with a long short-term memory (LSTM) network, where the TCN can sense local information and mine the deeper information of the sEMG signals, while LSTM, with its excellent temporal memory capability, can make up for the lack of the ability of the TCN to capture the long-term dependence of the sEMG signals, resulting in a better prediction. We validated the proposed method in the publicly available Ninapro DB1 dataset by selecting the first eight subjects and picking three types of wrist-dependent movements: wrist flexion (WF), wrist ulnar deviation (WUD), and wrist extension and closed hand (WECH). Finally, the proposed TCN-LSTM model was compared with the TCN and LSTM models. The proposed TCN-LSTM outperformed the TCN and LSTM models in terms of the root mean square error (RMSE) and average coefficient of determination (R2). The TCN-LSTM model achieved an average RMSE of 0.064, representing a 41% reduction compared to the TCN model and a 52% reduction compared to the LSTM model. The TCN-LSTM also achieved an average R2 of 0.93, indicating an 11% improvement over the TCN model and an 18% improvement over the LSTM model. [ABSTRACT FROM AUTHOR]

Modern low‐pressure turbine (LPT) pursues high blade loading to improve its efficiency while the possibility of boundary layer separation on the blades is still a challenging problem. The incidence angle is one of the main factors affecting the flow separation and laminar‐turbulent transition, which is of key importance for the design of LPT. In this work, based on the initial simulation results obtained using the Reynolds‐averaged Navier–Stokes (RANS) method, the flow past a single LPT cascade at three representative incident angles (i = −10°, 0°, +10°) is investigated using large‐eddy simulation (LES) method with approximately 26 million structured grids. The simulations are carried out with Open Source Field Operation and Manipulation (OpenFOAM) for an off‐design low Reynolds number condition Re = 40,000 and Ma = 0.5. The time‐averaged aerodynamic performances and three‐dimensional instantaneous flow characteristics of the LPT cascade are discussed in detail, and the results show that the blade loading and the transverse pressure gradient (TPG) from the pressure side to the suction side of leading edge (LE) increase with increasing incidence angle. At the incidence angle of +10°, the LPT cascade undergoes separation and reattachment from the LE to around 20% Cax on the suction surface, which weakens the separation phenomenon at the rear half of the suction surface and the total pressure loss downstream of the trailing edge (TE). It is worth noting that the RANS method underpredicts the blade boundary layer separation region compared with LES under these extreme conditions. These results may offer off‐design condition data for the future improvement of RANS models or experimental studies. [ABSTRACT FROM AUTHOR]

Ubiquitin chains regulate distinct signaling events through cooperative interactions with effector proteins and deubiquitinases. Measuring the strength of these interactions is often challenging; either large amounts of material are required or one of the binding partners must be labeled for detection. We sought to develop a label-free method for measuring binding of ubiquitin chains to the proteasome-associated deubiquitinase UCH37 and its binding partner RPN13. The method we describe here is based on a fluorescence polarization competition (FP comp ) assay in which fluorescent monoubiquitin is competed off the UCH37•RPN13 complex by the addition of unlabeled ubiquitin chains. We show that the UCH37•RPN13 complex displays higher affinity toward chains with more than two ubiquitin subunits. Removing the ubiquitin-binding PRU domain of RPN13 does not change affinities. These results suggest UCH37•RPN13 acts to selectively recruit proteins modified with long chains (>2 subunits) to the proteasome for degradation. We also demonstrate that the FP comp assay is suitable for high-throughput screening, which is important considering both UCH37 and RPN13 are potential targets for cancer therapy. [ABSTRACT FROM AUTHOR]

Membrane wetting and fouling substantially limits application and deployment of membrane distillation process. Designing high-performance superhydrophobic membranes offers an effective solution to solve the challenge. In this work, a highly durable superhydrophobic surface (water contact angle of 170.8 ± 1.3°) was constructed via a facile and rapid spray-coating of extremely hydrophobic SiO 2 nanoparticles onto a porous polyvinylidene fluoride (PVDF) substrate for membrane distillation. The superhydrophobic membrane coated by fluorinated SiO 2 nanoparticles exhibited a superior physicochemical stability in a wide range of extreme environments (i.e., NaOH, HCl, hot water, rust water, humic acid solution, ultrasonication, and high-speed water scouring). During 8-h continuous membrane distillation desalination experiment, the coated superhydrophobic membrane experienced a consistently stable water vapor flux (ca. 19.1 kg·m−2·h−1) and desalination efficiency (99.99 %). Additionally, such a stable superhydrophobicity endowed the spray-coated PVDF membrane to overcome membrane wetting and fouling during membrane distillation of highly saline solutions containing foulants (i.e., humic acid and rust). Results reported in this study provides a useful concept and strategy in facile construction of robust superhydrophobic membranes via spray-coating for effective membrane distillation. [Display omitted] • Spray-coating of hydrophobic SiO 2 was used to fabricate superhydrophobic membranes. • Superhydrophobic membrane experienced strong physicochemical stability in harsh environment. • Superhydrophobic membrane had a superior desalination efficacy in membrane distillation. • Superhydrophobic membrane had excellent antifouling properties during membrane distillation. [ABSTRACT FROM AUTHOR]

Abstract: In an early report, some of us have demonstrated that graphene-sheet films prepared by electrophoretic deposition (EPD) method have great potential as high-performance field emission cathode. We report that the field emission performance from such graphene-sheet films may be enhanced. We have investigated the correlation between topographic structures and local field emission characteristics of graphene-sheet films, prepared with changing EPD deposition time. Detailed experiments show that samples prepared with longer deposition time have better field emission performance. Both scanning electron microscopy and high resolution transmission electron microscopy images show that the topographic structure of the surface layer of the samples deposited with longer time is formed with higher density of graphene sheets with shorter length and fewer graphene layers, in comparison with those with shorter deposition times. Such topographic structure is found experimentally to give large field enhancement. Computer simulation further confirms that a thinner graphene sheet will give more significant geometrical field enhancement at the corner of graphene sheet. Theoretical analysis shows that in an EPD process, longer-length graphene sheets will be deposited before shorter ones, explaining why with longer deposition time, the topographic structure of surface layer consists of shorter-length graphene sheets. [Copyright &y& Elsevier]

To improve the threshold voltage and gate reliability of conventional enhancement-mode p-GaN-gated AlGaN/GaN high electron mobility transistors while maintaining a low on-resistance, an improved design solution for p-GaN HEMTs with P-I-N junction gate (PIN-HEMTs) has been proposed. Simulation results show that energy band modulation is achieved by adjusting the doping concentration and thickness of each layer of the PIN junction, and high-performance p-GaN gate HEMTs with adjustable threshold voltages ranging from 0.56 V to 4.75 V and gate breakdown voltages ranging from 19.8 V to 30.3 V would be prepared. The PIN-HEMT has a quasi-self-alignment property, which means that good gate control is independent of gate metal alignment. This not only improves the production efficiency but also solves the problems of weak gate control and electric field aggregation at the gate edge caused by the gate misalignment in conventional p-GaN gate HEMTs, thus realizing lower on-resistance and higher gate breakdown voltage, which demonstrates this proposed structure has excellent potentials for realizing effective and reliable high-power transistors. [ABSTRACT FROM AUTHOR]

Deciphering mechanisms controlling SNARE localization within the Golgi complex is crucial to understanding protein trafficking patterns within the secretory pathway. SNAREs are also thought to prime coatomer protein I (COPI) assembly to ensure incorporation of these essential cargoes into vesicles, but the regulation of these events is poorly understood. Here, we report roles for ubiquitin recognition by COPI in SNARE trafficking and in stabilizing interactions between Arf, COPI, and Golgi SNAREs in Saccharomyces cerevisiae. The ability of COPI to bind ubiquitin, but not the dilysine motif, through its N-terminal WD repeat domain of β'-COP or through an unrelated ubiquitin-binding domain is essential for the proper localization of Golgi SNAREs Bet1 and Gos1. We find that COPI, the ArfGAP Glo3, and multiple Golgi SNAREs are ubiquitinated. Notably, the binding of Arf and COPI to Gos1 is markedly enhanced by ubiquitination of these components. Glo3 is proposed to prime COPI-SNARE interactions; however, Glo3 is not enriched in the ubiquitin-stabilized SNARE-Arf-COPI complex but is instead enriched with COPI complexes that lack SNAREs. These results support a new model for how posttranslational modifications drive COPI priming events crucial for Golgi SNARE localization. [ABSTRACT FROM AUTHOR]

The key to achieve sustainable treatment of high-salinity dye-containing wastewater is effective fractionation of dyes and salts. In this study, a thin-film composite electro-nanofiltration membrane was successfully fabricated by co -deposition of levodopa and ε-polylysine onto a porous ultrafiltration membrane substrate. With the co -deposition of the polylevodopa/ε-polylysine composite coating on the substrate membrane, the surface properties were significantly regulated, resulting in decreased pore size, reduced surface negative charge density and lower specific electric resistance, thus enhancing their ion transfer and dye/salt fractionation efficacy. Specifically, the fabricated LDP-4 membrane (molecular weight cut-off of 408 Da) with a 4-h co-deposition experienced a 99.12 % reactive orange 16 dye rejection and 10.15 % NaCl rejection, indicating an impressive selectivity between dyes and salts. Additionally, the LDP-4 electro-nanofiltration membrane as anion conducting membrane exhibited a fast and efficient electro-driven transfer of Cl− ions. Notably, under an electric field, the fabricated LDP-4 electro-nanofiltration membrane can efficiently fractionate NaCl from the reactive orange 16/NaCl mixed solution, achieving a 98.89 % desalination efficiency and 99.79 % dye recovery. Furthermore, the LDP-4 membrane demonstrated remarkable anti-fouling property and long-term stability over an 8-cycle electro-nanofiltration operation. Therefore, the electro-nanofiltration membranes fabricated by co -deposition of levodopa and ε-polylysine show a promising potential in sustainable resource recovery from high-salinity dye-containing wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Rapid co-deposition of dopamine and APTS was used to construct superhydrophilic membranes. • Superhydrophilic membrane had an effective oil repellency with underwater oil contact angle of ∼163.5°. • Superhydrophilic membrane has a fast gravity-driven filtration for oil-in-water emulsions with a separation efficiency of >99.9 % • Incorporation of Cu NPs and polydopamine enables the membranes with complete antibacterial activity. Substantial discharge of industrial oily wastewater calls for an efficient and sustainable treatment for resource recovery. Superwetting membranes offer a feasible approach to fractionate oil species and water from oily wastewater for addressing this technical challenge. In this study, we proposed a useful strategy for constructing a superhydrophilic membrane with superior antibacterial properties through rapid co-deposition of dopamine and 3-aminopropyltriethoxysilane (APTS) initiated by ammonium persulfate on the Cu nanoparticles-loaded porous PVDF substrate. The resultant superhydrophilic membrane yielded an underwater oil contact angle of 163.5°, enabling a fast and robust gravity-driven filtration for various oil-in-water emulsions with a separation efficiency of >99.9 %. Additionally, incorporating of Cu nanoparticles and polydopamine endowed the superhydrophilic membrane with superior antibacterial activity (100 % inhibition efficiency against Escherichia coli), and thereby remarkably enhancing the anti-biofouling performance. This study provides a viable approach to design high-performance membranes for separation of oil-in-water emulsions, with promising applications in the industrial and environmental sectors. [ABSTRACT FROM AUTHOR]

The growing concern over heavy metal ion contamination in industrial wastewater, posing a significant threat to global public health, has led to a heightened interest in devising efficient removal methods. Nanofiltration, while promising, faces a substantial challenge in simultaneously achieving a high rejection of heavy metal cations and maintaining an elevated water permeance. In response, this study utilizes a simple approach by employing choline chloride with a quaternary ammonium group to modify the surface of PEI-TMC membrane, leading to the design of a high-performance PEI-TMC-CC membrane. The choline chloride modification optimized the surface morphology, hydrophilicity, roughness, and combined the Donnan exclusion effect as well as sieving effect, enabling the PEI-TMC-CC membrane to achieve an exceptional rejection of heavy metal ions while retaining a great water permeance. An impressive water permeance 10.0 L m−2 h−1 bar−1 was performed by the PEI-TMC-CC membrane, nearly three times that of traditional PEI-TMC membranes. Concurrently, the PEI-TMC-CC membrane demonstrated an impressive rejection of heavy metals Cd2+, Pb2+, Ni2+, Zn2+, and Cu2+, reaching rejections of 98.3 %, 95.9 %, 98.1 %, 98.5 % and 99.1 %, respectively. Moreover, density functional theory (DFT) calculations confirmed the improved hydrophilicity of choline chloride molecules, aligning with experimental results. The modification of traditional nanofiltration membranes using cost-effective, hydrophilic, positively charged chemicals not only leads to significant performance improvements but also holds the potential to advance the development of positively charged nanofiltration membranes tailored for the removing of heavy metals cations from wastewater. This approach demonstrates promising prospects for industrial applications and further development. [Display omitted] • The affordability and non-toxic choline chloride was employed to modify the surface of PEI-TMC membrane. • The hydrophilicity of choline chloride were demonsitrated by Density Functional Theory method. • The choline chloride improve the membrane permeance while retaining the great rejection of heavy metal cations. [ABSTRACT FROM AUTHOR]

High-salinity textile wastewater is a pressing environmental concern, urgently requiring the appropriate treatment. Sustainable management of high-salinity textile wastewater via fractionation of the existing dyes and inorganic salts (NaCl) using selective separation membranes is a key approach to address this detrimental concern. Herein, tight composite ultrafiltration membranes with impressive antibacterial function were constructed using one-step co-deposition of dopamine and tobramycin on the porous substrate to fractionate the dyes and NaCl. Triggered by ammonia persulfate, the polydopamine/tobramycin coating layer imparts the fabricated composite ultrafiltration membranes with tight surface structure and narrow pore size distribution, enabling effective dyes/salts fractionation. Specifically, the tight composite ultrafiltration membrane with a molecular weight cutoff of 3692 Da experienced a > 98.0 % rejection against various reactive dyes (molecular weight: <1000 Da) with nearly complete salt transmission (<0.8 % NaCl rejection), demonstrating an effective fractionation of dyes and salts. Additionally, the incorporated tobramycin as a broad-spectrum antibiotic endowed the tight composite ultrafiltration membrane with a sufficient inhibition efficiency (i.e., 100 %) against E. coli bacteria in a short-time contact (i.e., 3 min). Thereby, the tight composite ultrafiltration membrane constructed by fast co-deposition of dopamine and tobramycin established an unparalleled platform technology for sustainable resource recovery (dyes or salts) from high-salinity textile wastewater. [Display omitted] • Tight ultrafiltration (UF) membrane with 3692 Da MWCO was designed by rapid co-deposition of dopamine and tobramycin. • Tight UF membrane had an impressive rejection of >98.0 % for various reactive dyes with >99.2 % NaCl transmission. • Tight UF membrane showed a robust stability in fractionation of dyes and salts. • Tight UF membrane yielded a 100 % inhibition efficiency against E. coli for mitigating the biofouling. [ABSTRACT FROM AUTHOR]

Carbon nanotube (CNT) film has great potential in the application as a cold cathode in vacuum power electron devices. Pulse field emission of CNT film is investigated to achieve large current and current density. A maximum current of 16 mA is obtained from a 0.02-cm^2 CNT film with a current density of 800 mA/cm^2. The pulsewidth and area of CNT film have strong effects on field emission characteristics of CNT film, such as total current, current density, and current stability. The reason for this is discussed in detail. The results are useful for the design of the large current and current density CNT cold cathodes. [ABSTRACT FROM AUTHOR]

To realize the complementary circuit on the GaN-on-Si platform, an investigation of p-channel heterostructure field-effect transistors (p-HFETs) is necessary. In this study, an analytical model for the estimation of the threshold voltage (${V}_{\text {TH}}$) for GaN-based p-HFETs was developed. In this model, the impact of polarization charges at different interfaces, the influence of interface charges at oxide/GaN interface, as well as the out-diffusion effect of Mg dopant in the p-GaN layer were all taken into consideration for systematic exploration. Herein, GaN-based p-HFETs were fabricated to verify the relationship between the ${V}_{\text {TH}}$ and the thickness of the GaN channel layer by using the proposed model. The ${V}_{\text {TH}}$ model was further confirmed through TCAD simulations. The influences of the thickness of oxide layer, Mg doping concentration in p-GaN layer, and the Al mole fraction of AlxGa $_{{1}-{x}}\text{N}$ layer on ${V}_{\text {TH}}$ were also discussed in detail. The model serves as more accurate guidance for the optimization of such p-HFETs design and complementary circuits. [ABSTRACT FROM AUTHOR]

The gate and drain bias dependence of hot electron-induced degradation in GaN-based metal–insulator–semiconductor high electron mobility transistors (MIS-HEMTs) was investigated in this work. Devices exhibit an abnormal increase in peak transconductance (${G}_{m}$ ,max) during hot carrier stress (HCS) and a partially quick recovery of that after removing the electrical stress. A physical model is proposed to explain the abnormal electrical characteristics caused by HCS. By using density functional theory (DFT), we calculated the energy for electrons to dehydrogenate preexisting [NGaH3]−1 complexes in GaN layer during stress. The dehydrogenation of defects affects the Gm,max of devices. Meanwhile, the neutralization of donor traps in AlGaN barrier layer also plays a significant role in the increase of Gm,max and the detrapping effect of electrons from these traps after removing the electrical stress accounts for the partially quick recovery of ${G}_{m, \text{max}}$. [ABSTRACT FROM AUTHOR]

The linkage, length, and architecture of ubiquitin (Ub) chains are all important variables in providing tight control over many biological paradigms. There are clear roles for branched architectures in regulating proteasome-mediated degradation, but the proteins that selectively recognize and process these atypical chains are unknown. Here, using synthetic and enzyme-derived ubiquitin chains along with intact mass spectrometry, we report that UCH37/UCHL5, a proteasome-associated deubiquitinase, cleaves K48 branched chains. The activity and selectivity toward branched chains is markedly enhanced by the proteasomal Ub receptor RPN13/ADRM1. Using reconstituted proteasome complexes, we find that chain debranching promotes degradation of substrates modified with branched chains under multi-turnover conditions. These results are further supported by proteome-wide pulse-chase experiments, which show that the loss of UCH37 activity impairs global protein turnover. Our work therefore defines UCH37 as a debranching deubiquitinase important for promoting proteasomal degradation. • UCH37 cleaves branched ubiquitin chains at the K48 position • The proteasomal subunit RPN13 enhances the activity of UCH37 • Proteasome-bound UCH37 retains selectivity for branched chains • UCH37-mediated chain editing potentiates proteasome-mediated degradation Using designer ubiquitin chains and intact mass spectrometry to characterize heterogeneous ubiquitin conjugates, Deol et al. discovered that the ubiquitin C-terminal hydrolase UCH37/UCHL5 cleaves branched chains bearing K48 linkages. The debranching activity of UCH37 is enhanced by the proteasome subunit RPN13. Loss of UCH37 activity on the proteasome impedes the degradation of proteins modified with branched chains. [ABSTRACT FROM AUTHOR]