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Peripheral nerve stimulators have emerged as a crucial instrument in the realm of neurological disease, capable of modulating nerve activity through precisely targeted electrical stimulation to specific sites within the nervous system. Herein, a new wireless battery‐free peripheral nerve stimulation device for remote muscle activation is developed. The device with conch‐inspired bionic design can be wirelessly powered and controlled by a mobile phone playing audio via the piezoelectric effect. The device consists of two parts: a conch‐like signal‐intensifying piezoelectric resonator for converting acoustic wave into electrostimulation signal; and a pedestal with stimulation electrodes for transmitting the electrostimulation signal to a peripheral nerve. For remote nerve intervention, a programmed audio tone from one mobile phone can be tele‐transmitted from other phones according to the desired stimulation protocols. In‐vivo experiments in stimulating the sciatic nerve in mice showed that the device can activate muscles (e.g., 1 Hz 920 mV for 26 degree of leg movement), and the neuron‐muscle interaction has been confirmed by electromyogram (EMG). The wireless peripheral nerve stimulation conch achieves feasible remote muscle activation without batteries, and can extend the scope of self‐powered techniques for telemedicine and limb/trunk rehabilitation. [ABSTRACT FROM AUTHOR]

The effective and targeted treatment of resistant cancer cells presents a significant challenge. Targeting cell ferroptosis has shown remarkable efficacy against apoptosis‐resistant tumors due to their elevated iron metabolism and oxidative stress levels. However, various obstacles have limited its effectiveness. To overcome these challenges and enhance ferroptosis in cancer cells, we have developed a self‐powered photodynamic therapeutic tablet that integrates a ferroptosis inducer (FIN), imidazole ketone erastin (IKE). FINs augment the sensitivity of photodynamic therapy (PDT) by increasing oxidative stress and lipid peroxidation. Furthermore, they utilize the Fenton reaction to supplement oxygen, generating a greater amount of reactive oxygen species (ROS) during PDT. Additionally, PDT facilitates the release of iron ions from the labile iron pool (LIP), accelerating lipid peroxidation and inducing ferroptosis. In vitro and in vivo experiments have demonstrated a more than 85% tumor inhibition rate. This synergistic treatment approach not only addresses the limitations of inadequate penetration and tumor hypoxia associated with PDT but also reduces the required medication dosage. Its high efficiency and specificity towards targeted cells minimize adverse effects, presenting a novel approach to combat clinical resistance in cancer treatment. [ABSTRACT FROM AUTHOR]

With the rapid development of textile technology, single‐function textile finishing is difficult to meet the current needs of people for textiles. Textiles with flame retardancy, superhydrophobicity, UV resistance, and other functions are increasingly favored by people. At present, most of the preparation processes of multifunctional textiles are complex and time‐consuming. In this work, a flame retardant hexamethylenediamine tetramethylene phosphate ammonium salt of hexamethylenediamine ‐ N, N, N′, N′ ‐ tetra (methylphosphonic acid) (AHDTMPA) was synthesized using hexamethylenediamine tetramethylene phosphate (HDTMPA) and urea with aqueous solution as solvent. Then AHDTMPA and cetyltrimethoxysilane were added into the solution with methyl trimethoxysilane (MTMOS) and tetraethyl orthosilicate (TEOS) as precursors to obtain a multifunctional sol. Finally, the multifunctional cotton fabric can be obtained by immersing the cotton fabric in the multifunctional sol in one‐step. The limiting oxygen index (LOI) and water contact angle (WCA) value of the finished cotton fabric was 27.6% and 131.4°, respectively. The FT‐IR characterization results and the SEM analysis verified the synthesis of AHDTMPA. The micro calorimeter combustion (MCC) and thermo gravimetric (TG) analysis indicated that the finished samples had less heat release capacity and less weight loss. The smoke density test showed good smoke suppression of the finished cotton fabric. Moreover, the whiteness of finished samples was nearly unchanged. In this work, the flame retardant and hydrophobic multi‐functional cotton fabric was prepared by one‐step, and the method is simple and efficient. The prepared functional cotton fabrics can be widely used in home textile fabrics, automotive interior fabrics, clothing fabrics, flags, tents, and protective clothing. [ABSTRACT FROM AUTHOR]

Abstract: As an intertidal species, Apostichopus japonicus is subject to diel and seasonal temperature fluctuations. Color variation is a distinct characteristic of A. japonicus, and a new color morph, purple A. japonicus, was recently found on the coast of Rushan, Weihai City. This study was conducted to compare the performance of green, white, and purple color morphs of A. japonicus at different water temperatures to help improving aquaculture technology and management. In this study, green, white, and purple color morphs of juvenile A. japonicus (1.5 ± 0.1 g) were cultured at 10, 14, 18, 22, and 26 C for 60 d, according to the suitable temperature range for sea cucumber growth. Temperature was shown to have a significant effect on growth, energy budget, and physiology of sea cucumbers (P < 0.05). Specific growth rates, feed conversion efficiencies, and the proportion of energy allocated to growth of all three color morphs were optimal at 18 C. Activities of the enzymes related with oxidative stress, immune response, and digestion were determined. Superoxide dismutase (SOD) and trypsin activities generally reached a maximum in all three color morphs at 18 C. The purple color morph of A. japonicus was higher in growth rate, food conversion efficiency, and proportion of energy allocated to growth than green and white color morphs at 18 and 22 C, consistent with its higher trypsin and SOD activity, indicating the mutual effect of growth and physiology. At 18, 22, and 26 C, the green color morph had the highest level of lysozyme activity and purple color morph had the lowest, indicating possible infection by external pathogens of green color morph, which might be caused by high temperature. These results suggested that the optimum temperature for culture of the three color morphs was approximately 18 C, the purple had a better adaption to high temperature, and the green and white color morphs may be more susceptible to thermal stress than the purple color morph. [ABSTRACT FROM AUTHOR]

Abstract: A new self‐powered brain‐linked vision electronic‐skin (e‐skin) for mimicking retina is realized from Polypyrrole/Polydimethysiloxane (Ppy/PDMS) triboelectric‐photodetecting pixel‐addressable matrix. The e‐skin can be driven by human motion, so no external electricity power is needed in both photodetecting and signal transmitting processes. The triboelectric output is significantly dependent on the photo illumination, which can act as visual bionic electric impulse. Taking blue illumination (405 nm) as an example, as the e‐skin is exposed to 100 µW cm−2 illumination, the output current decreases from 7.5 to 4.9 nA, and the photosensitivity is 34.7. And the photosensitivity of the e‐skin keeps stable with different bending angles and force. The e‐skin is flexible enough to combine with human body and can be driven by blinking eyes to detect UV illumination. In addition, the 4 × 4 photodetecting unit matrix in the e‐skin can map single‐point and multipoint illumination‐stimuli (visual‐image recognition) via the multichannel data acquisition method. Furthermore, the e‐skin can directly transmit photodetecting signals into mouse brain for participating in the perception and behavior intervention. This new self‐powered perception device can lower down the production cost of traditional complex sensory‐substitution system, and can be easily extended to various brain–machine interaction applications. [ABSTRACT FROM AUTHOR]

Rational design of non-noble materials as highly efficient, economical, and durable bifunctional catalysts for oxygen evolution and reduction reactions (OER/ORR) is currently a critical obstacle for rechargeable metal-air batteries. A new route involving S was developed to achieve atomic dispersion of Fe-N x species on N and S co-decorated hierarchical carbon layers, resulting in single-atom bifunctional OER/ORR catalysts for the first time. The abundant atomically dispersed Fe-N x species are highly catalytically active, the hierarchical structure offers more opportunities for active sites, and the electrical conductivity is greatly improved. The obtained electrocatalyst exhibits higher limiting current density and a more positive half-wave potential for ORR, as well as a lower overpotential for OER under alkaline conditions. Moreover, a rechargeable Zn-air battery device comprising this hybrid catalyst shows superior performance compared to Pt/C catalyst. This work will open a new avenue to design advanced bifunctional catalysts for reversible energy storage and conversion devices. [ABSTRACT FROM AUTHOR]

A new flexible smelling electronic skin (e-skin) has been realized from PANI(polyaniline)/PTFE(polytetrafluoroethylene)/PANI sandwich nano­structures basing on the triboelectrification/gas-sensing coupling effect. The e-skin can be driven by human motion/breath and efficiently convert mechanical vibration into electric impulse. And the output current/voltage is significantly dependent on the environmental atmosphere (volatile organic compounds in air), which can act as olfactory bionic electric impulse. Taking ethanol gas as an example, the detection limit of the e-skin at room temperature is 30 ppm, and the response is up to 66.8 upon exposure to 210 ppm ethanol. Interestingly, the response of the e-skin keeps stable with different dimensional sizes or under different strains/bending status. The working mechanism can be ascribed to the coupling of triboelectrification effect and surface reaction at the interfaces. Furthermore, an application of the flexible smelling e-skin for visually identifying drunken driver without any external electricity power has been demonstrated. The results can open a possible new direction for the development of specialized-function e-skin and will further expand the scope for self-powered nanosystems. [ABSTRACT FROM AUTHOR]

Ajoint of ZrB2-SiC ceramic to Ti6Al4Valloy was achieved successfully by contact reactive brazing with Ti/Cu lamination. The microstructure and chemical composition of joining interfaces were investigated by electron backscattered diffraction, energy dispersive spectroscopy and X-ray diffraction. The results revealed that ZrB2 had much faster decomposing velocity than SiC in Ti-Cu liquid alloy. Two types of distribution of TiB whiskers were produced on ceramic surface due to different growing conditions. The microstructural evolution with different brazing temperatures was analyzed. The mechanical properties of the joints were evaluated by microhardness and shear tests. The maximum shear strength reached 90.7MPa with brazing temperature at 920 °C for 10 min. [ABSTRACT FROM AUTHOR]

Flexible self‐charging power cells (SCPCs) are fabricated from flexible graphene electrodes and Kapton shells. The cells can be charged from 500 to 832 mV within 500 s by periodic compressive stress (34 N, 1 Hz). The flexible SCPC can be efficiently charged from a small amount of mechanical energy, such as by finger pressing or a bicycle tire rolling. [ABSTRACT FROM AUTHOR]

The effect of Yb3+ concentration on the fluorescence of 12CaO·7 Al2O3:Ho3+/Yb3+ polycrystals is investigated. The Raman spectra of pure C12A7 under 633-nm excitation show that the highest photon energy is 787.267 cm−1, which is not much bigger than general fluorides, so it can realize high efficiency upconversion. The upconversion emission spectra suggest that the green upconversion emission centered at 548 nm and the red upconversion emission at 662 nm correspond to the 5F4/5S2→5I8 and 5F5→5I8 transition of Ho3+ ions, respectively. The intensity of the upconversion luminescence and the ratio of red to green are changed with Yb3+ ion concentration. The pump dependence and luminescence decay dynamics spectra show the green and red upconversion emissions are populated by a two-photon process, and the upconversion mechanisms are analyzed. The relative luminous efficiencies of green and red emissions are 2.035% and 0.7%, respectively. The normalized efficiency obtained for green emission of Ho3+ at RT when the sample is excited by 980-nm light with an absorbed intensity of 7.5 W/cm2 is 0.27 cm2/W. This result is comparable to the values obtained in YF3 for the Yb3+, Er3+ green emission. The C12A7 with upconversion red and green light will be a promising luminous material. [ABSTRACT FROM AUTHOR]

Congruent Er3+(3 mol%):LiNbO3 crystals codoped with ZnO (X mol %, X=0, 3, 6 and 7) were grown by the Czochralski technique. The Er contents in the crystals were measured by an inductively coupled plasma atomic emission spectrometer (ICP-AES). Under 800 nm excitation, the upconversion emission spectra reveal an enhancement of the green emission with respect to the red emission when the Zn2+ ions are introduced into Er:LiNbO3 crystal. The effect of Zn2+ ions concentration on the intensity ratio of the green to red emission has been investigated. Two cross-relaxation processes (2H11/2 + 4I13/2 → 4I11/2 + 4F9/2 and 4F7/2 + 4I11/2 → 4F9/2 + 4F9/2) are involved in populating the 4F9/2 state, which bypass the green-emitting states. The OH- absorption spectra indicate that the Zn2+ codoping leads to a decreased concentration of Er3+ cluster sites contributing to the enhancement of the green emission. The studies on UV-vis absorption spectra show that the heavily codoped with Zn2+ results in the reformation of the Er3+ cluster sites in Er:LiNbO3. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Summary: The damped outrigger system emerged as an improvement of the conventional outriggers with the aim to provide supplemental damping and to contribute to the vibration control in super tall buildings where this system is usually applied. In addition to viscous dampers (VDs), buckling‐restrained braces (BRBs) have also been employed as energy dissipating members in outriggers. Nevertheless, the combined use of outriggers with VDs and BRBs in the same structure has not yet been studied. Such combination can contribute to achieve an effective multiperformance design of super tall buildings. This paper presents a study whose main objective was to determine the optimal vertical combination of two types of energy dissipation outriggers to control the seismic responses of a 9‐zone super tall model structure. Outriggers with VDs (OVDs) and outriggers with BRBs (OBRBs) were placed at the different zones of the structure considering all the possible combinations and in configurations of up to four outriggers. The effects of these combinations on the seismic performance of the structure were studied through parametric analysis and optimization methods. This form of the outrigger system is defined in this paper as combined energy dissipation outrigger system. The results indicate that when two energy dissipation outriggers are used, the combination of OBRB plus OVD shows superior seismic performance compared with other double‐outrigger configurations. In addition, the results show that the locations of OVDs and OBRBs play an important role in the structure behavior; it was found that it is more beneficial to place OBRBs above OVDs. [ABSTRACT FROM AUTHOR]

Reliable joining of graphite and copper is achieved by means of a multilayer structure: niobium, which is used as stress‐relief interlayer, is joined to copper on one side by transient liquid phase (TLP) bonding and to graphite on the other side, using Ti/Cu foils as a filler alloy. The joints prepared by different parameters are analyzed in terms of microstructure, joint strength, and fracture behavior. With low joining temperature and low Ti content, a ductile banded Cu/TiCu4 layer forms between graphite and Nb by peritectic reaction. The dissolution‐precipitation of Nb in TiC particles can help to reduce the brittleness on graphite interface. The TLP bonding between Nb and copper results in a narrow diffusion layer in copper substrate. The maximum shear strength of joints reaches 32 MPa as using 11.3 wt% Ti at 1000 °C. The fracture modes change from bowl shape cracks in graphite/Cu joints to multi‐step cracks in graphite/Nb/Cu joints. Reliable joining of graphite and copper is achieved by Ti/Cu/Nb/Ti multilayer structure. The joining involves two simultaneously processes, namely, Ti/Cu contact brazing on graphite/Nb interface and TLP bonding on Nb/copper interface. The joints prepared by different parameters are analyzed in terms of microstructure, joint strength and fracture behavior. [ABSTRACT FROM AUTHOR]