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Highlights: The bioinspired self-sensing actuated gradient hydrogel was developed by a wettability-based method via precipitation of MoO2 nanosheets. Self-sensing actuated gradient hydrogel combined ultrafast thermo-responsive actuation (21° s–1), exceptional photothermal efficiency (3.7 °C s–1) and high sensing properties (GF = 3.94). The first self-sensing remote interaction system based on gradient hydrogel actuators and robotic hands was constructed. The development of bioinspired gradient hydrogels with self-sensing actuated capabilities for remote interaction with soft-hard robots remains a challenging endeavor. Here, we propose a novel multifunctional self-sensing actuated gradient hydrogel that combines ultrafast actuation and high sensitivity for remote interaction with robotic hand. The gradient network structure, achieved through a wettability difference method involving the rapid precipitation of MoO2 nanosheets, introduces hydrophilic disparities between two sides within hydrogel. This distinctive approach bestows the hydrogel with ultrafast thermo-responsive actuation (21° s−1) and enhanced photothermal efficiency (increase by 3.7 °C s−1 under 808 nm near-infrared). Moreover, the local cross-linking of sodium alginate with Ca2+ endows the hydrogel with programmable deformability and information display capabilities. Additionally, the hydrogel exhibits high sensitivity (gauge factor 3.94 within a wide strain range of 600%), fast response times (140 ms) and good cycling stability. Leveraging these exceptional properties, we incorporate the hydrogel into various soft actuators, including soft gripper, artificial iris, and bioinspired jellyfish, as well as wearable electronics capable of precise human motion and physiological signal detection. Furthermore, through the synergistic combination of remarkable actuation and sensitivity, we realize a self-sensing touch bioinspired tongue. Notably, by employing quantitative analysis of actuation-sensing, we realize remote interaction between soft-hard robot via the Internet of Things. The multifunctional self-sensing actuated gradient hydrogel presented in this study provides a new insight for advanced somatosensory materials, self-feedback intelligent soft robots and human–machine interactions. [ABSTRACT FROM AUTHOR]

In this paper, we aim to derive an exact solution to a linearised version of the geophysical equations in the β -plane setting. The obtained explicit solution represents a steady purely azimuthal stratified flow with a flat surface and an impermeable flat bed that is suitable for describing the Equatorial Current. Moreover, we show that the thermocline exhibits some monotonicity properties. [ABSTRACT FROM AUTHOR]

Highlights: The skin-inspired multifunctional ultra-tough electronic skin with tunable mechanical properties was developed by a physically cross-linking salting-freezing-thawing method. The hydrogel integrates transparency (>60%), super toughness (up to 13.96 MJ m−3), good antibacterial properties (E. coli and S. aureus), UV protection (Filtration: 80%–90%), high electrical conductivity (4.72 S m−1), anti-swelling and recyclability. As a human–machine interface, it can be used for complex underwater activities, information encryption/decryption and finger joint rehabilitation training. Multifunctional supramolecular ultra-tough bionic e-skin with unique durability for human–machine interaction in complex scenarios still remains challenging. Herein, we develop a skin-inspired ultra-tough e-skin with tunable mechanical properties by a physical cross-linking salting-freezing-thawing method. The gelling agent (β-Glycerophosphate sodium: Gp) induces the aggregation and binding of PVA molecular chains and thereby toughens them (stress up to 5.79 MPa, toughness up to 13.96 MJ m−3). Notably, due to molecular self-assembly, hydrogels can be fully recycled and reprocessed by direct heating (100 °C for a few seconds), and the tensile strength can still be maintained at about 100% after six recoveries. The hydrogel integrates transparency (> 60%), super toughness (up to 13.96 MJ m−3, bearing 1500 times of its own tensile weight), good antibacterial properties (E. coli and S. aureus), UV protection (Filtration: 80%–90%), high electrical conductivity (4.72 S m−1), anti-swelling and recyclability. The hydrogel can not only monitor daily physiological activities, but also be used for complex activities underwater and message encryption/decryption. We also used it to create a complete finger joint rehabilitation system with an interactive interface that dynamically presents the user's health status. Our multifunctional electronic skin will have a profound impact on the future of new rehabilitation medical, human–machine interaction, VR/AR and the metaverse fields. [ABSTRACT FROM AUTHOR]

Detection methods with high sensitivity and short assay time are urgently required for quantitative analysis of small-molecule hazardous substances in food monitoring. In this work, a new anti-aflatoxin B1 (AFB1) nanobody was screened from an immunized nanobody library, and an ultrafast one-step detection of AFB1 without immobilization and multi-step washing was developed based on magnetic separation technology and nanobody (Nb)-alkaline phosphatase (ALP) fusion protein. Compared to conventional one-step chemiluminescent enzyme-linked immunosorbent assay (CLEIA) based on Nb-ALP, it was surprising to find the sensitivity and lowest limit of detection (LOD) of this method was significantly improved about threefold and fivefold separately, and the total assay time could be reduced to 30 from 120 min. Under optimal conditions, the developed method achieved the sensitive detection of AFB1 with LOD with 0.743 pg mL−1, IC50 = 0.33 ng mL−1, the linear range was 7.23 pg mL−1 ~ 12.38 ng mL−1, and showed powerful tolerance and utility for complex matrix environments in sample detection. It is believed this method could provide a newly way for the quick and sensitive detection of AFB1 and could expand the application of Nbs. [ABSTRACT FROM AUTHOR]

Laminitis is one of the most important and intractable diseases in dairy cows, which can lead to enormous economic losses. Although many scholars have conducted a large number of studies on laminitis, the therapeutic test of medicinal plants in vitro is really rare. Licochalcone A is proved to possess anti-inflammatory and anti-oxidant properties. But the effect of licochalcone A on LPS-induced inflammatory claw dermal cells has not been discovered yet. In this study, the primary dairy cow claw dermal cells were treated with gradient concentrations of licochalcone A (1, 5, 10 µg/mL) in the presence of 10 µg/mL lipopolysaccharides (LPS). The results indicated that licochalcone A reduced the concentrations of inflammation mediators (TNF-α, IL-1β and IL-6), increased the activity of SOD, reduced the levels of MDA and ROS, downregulated the mRNA expressions of TLR4 and MyD88, suppressed the protein levels of p-IκBα and p-p65, and upregulated the protein expression of PPARγ. In summary, licochalcone A protected dairy cow claw dermal cells against LPS-induced inflammatory response and oxidative stress through the regulation of TLR4/MyD88/NF-κB and PPARγ signaling pathways. [ABSTRACT FROM AUTHOR]

Silicon photonics has emerged as one of the most prominent technological platforms for photonic integration. Compared with silicon, silicon nitride has a much broader wavelength transparency range, lower propagation loss, and less sensitivity to temperature changes, making it suitable for the manufacture of passive devices. However, silicon nitride films deposited directly on the wafer by low-pressure chemical vapor deposition exhibit large tensile stress, which may cause cracks. In the work presented herein, a process was developed to fabricate crack-free 400-nm-thick silicon nitride films based on the 200-mm complementary metal–oxide–semiconductor platform. The silicon nitride films were deposited in two steps, each followed by annealing. During the annealing, Si–H and N–H bonds in the film were broken and Si–N bonds were formed, thus improving the uniformity of the film and releasing the stress. Fourier-transform infrared measurements indicated that the films were in near-stoichiometric condition. Wafer-level testing showed that the propagation loss of an 800-nm-wide strip waveguide was 0.5 dB/cm to 0.7 dB/cm for the C-band. The insertion loss of waveguide crossing was approximately 0.15 dB, and the crosstalk was below –43 dB. The insertion loss of 1 × 2 multimode interference was less than 0.3 dB, and the nonuniformity was smaller than 10%. [ABSTRACT FROM AUTHOR]

The aim of this paper is to explore the phenomenon of aperiodic stochastic resonance in neural systems with colored noise. For nonlinear dynamical systems driven by Gaussian colored noise, we prove that the stochastic sample trajectory can converge to the corresponding deterministic trajectory as noise intensity tends to zero in mean square, under global and local Lipschitz conditions, respectively. Then, following forbidden interval theorem we predict the phenomenon of aperiodic stochastic resonance in bistable and excitable neural systems. Two neuron models are further used to verify the theoretical prediction. Moreover, we disclose the phenomenon of aperiodic stochastic resonance induced by correlation time and this finding suggests that adjusting noise correlation might be a biologically more plausible mechanism in neural signal processing. [ABSTRACT FROM AUTHOR]

α-L-Fucosidase (AFU) is a promising therapeutic target for the treatment of inflammation, cancer, cystic fibrosis, and fucosidosis. Some of the existing analytical methods for the assessment of AFU activity are lacking in sensitivity and selectivity, since most of them are based on spectrofluorimetric methods. More recently, mass spectrometry (MS) has evolved as a key technology for enzyme assays and inhibitor screening as it enables accurate monitoring of the conversion of substrate to product in enzymatic reactions. In this study, UHPLC-MS has been utilized to develop a simple, sensitive, and accurate assay for enzyme kinetics and inhibition studies of AFU3, a member of the AFU family. A reported method for analyzing saccharide involving a porous graphitic carbon column, combined with reduction by NaBH4/CH3OH, was used to improve sensitivity. The conversion of saccharide into alditol could reach nearly 100% in the NaBH4 reduction reaction. In addition, the bioanalytical quantitative screening method was validated according to US-FDA guidance, including selectivity, linearity, precision, accuracy, stability, and matrix effect. The developed method displayed a good accuracy, high sensitivity (LOD = 0.05 mg L−1), and good reproducibility (RSD < 15%). The assay accurately measured an IC50 value of 0.40 μM for the known AFU inhibitor, deoxyfuconojirimycin, which was consistent with results reported in the literature. Further validation of the assay was achieved through the determination of a high Z′-factor value of 0.89. The assay was applied to screen a marine-derived chemical library against AFU3, which revealed two marine-oriented pyrimidine alkaloids as potential AFU3 inhibitors. Graphical abstract [ABSTRACT FROM AUTHOR]

Copper phthalocyanine oligomer (CuPc) possessing high dielectric constant was grafted onto acrylic elastomer (ACM) backbones to fabricate elastomeric nanocomposites (referred to here as ACM- g-CuPc) with high dielectric constant. High strain of ACM- g-CuPc film could be achieved at low electric field. The electric field-induced strain properties of ACM- g-CuPc films were studied from four aspects: the pre-stretch value, butyl acrylate (BA) content, active region-to-window radius ratio, and strain hysteresis. The results revealed that the area strain in the active region first increased and then decreased with the increase in the pre-stretch value; however, it increased with the increase in BA content and decreased with the increase in the active region-to-window radius ratio. When the active region-to-window radius ratio was 1:5, the ACM- g-CuPc film with 60 wt% BA content and 150 × 150 % pre-stretch value exhibited the maximum area strain of 23.8 % under an electric field of 12.5 MV m. In a complete driving period, ACM- g-CuPc film exhibited a strain hysteresis phenomenon, forming a strain hysteresis loop. [ABSTRACT FROM AUTHOR]

To increase the electric energy density of dielectric elastomer substantially, high dielectric constant nanocomposites were developed using polyurethane (PU) as matrix and copper phthalocyanine oligomer (CuPc)-a high dielectric constant organic semiconductor-as filler. Transmission electron microscope (TEM)-observed morphologies revealed that the sizes of CuPc particles in nanocomposite of PU chemically attached with 8.78 vol% of CuPc were in the range of 10-20 nm, much smaller than the sizes (250-600 nm) in the physical blend of PU with the same volume fraction of CuPc. At 100 Hz, the nanocomposite film exhibited a dielectric constant of 391, representing more than 60-fold increase with respect to the pure PU. The enhanced dielectric response of the nanocomposite makes it possible to induce a high electromechanical response under a much reduced electric field (a strain of 17.7 % was achieved under a field of 10 V/μm). [ABSTRACT FROM AUTHOR]

All-organic three-component composites were fabricated by embedding conductive polyaniline (PANI) into a dielectrically enhanced matrix of poly(vinylidene fluoride-trifluoroethylene- chlorofluoroethylene) [P(VDF-TrFE-CFE)] with both chemically grafted and physically blended copper phthalocyanine oligomer (CuPc). Dielectric behavior of the composites with different volume fraction of dispersed PANI phase can be described by percolation theory. One of such composites with the PANI content close to the percolation threshold ( f = 0.146) has a dielectric constant 516 and a loss factor of 0.51 at 100 Hz, and the breakdown field is 28.0 MV/m. The composite remains very flexible with an elastic modulus close to that of the parent copolymer. [ABSTRACT FROM AUTHOR]