Encapsulating eutectogels for stretchable humidity-resistant strain sensors.

Eutectogels are stretchable ionic conductors extensively developed in recent years, owing to their distinct advantages of low cost, non-volatility, non-toxicity, and outstanding biocompatibility. However, the susceptibility to humidity caused by the exchange of water molecules between the interiors of eutectogels and the external environment greatly restricts their practical applications. Here, a dip-coating strategy is proposed to fabricate a P(MEA-co-IBA) elastomer-coated P(AAC-co-AAM) eutectogel to achieve satisfactory humidity-resistant capability. The hydrophobic elastomer coating significantly suppresses water exchange without harming the stretchability (>500%) and conductivity of the eutectogel. Strong adhesion forms at the eutectogel-coating interface due to the formation of an interpenetrating layer. The superior electromechanical performances of encapsulated eutectogels enable stretchable ionotronic devices with stable electrical performance (>1 h) and remarkable water-droplet/moist resistances during static/dynamic loadings. A humidity-resistant encapsulated eutectogel-based wearable strain sensor is further demonstrated. The proposed humidity-resistant eutectogels are promising candidates for soft and wearable ionotronics for practical applications.

Progress of Hydrophobic Ionogels: A Review.

The emergence of hydrophobic ionogels composed of hydrophobic polymer matrices and hydrophobic ionic liquids has drastically broadened the applications of ionic devices, especially for underwater explorations. Compared with traditional ionogels, hydrophobic ones are capable of achieving long-term stability in ambient and aqueous environments. In this review, the latest research developments of intrinsically hydrophobic ionogels are summarized, with particular emphases placed on the materials, mechanisms and applications. The basic issues about hydrophobic ionogels, including the material systems, dynamic gelation bonds and network structures are elucidated. The up-to-date advent of the ambient/underwater applications of hydrophobic ionogels concerning adhesion, self-healing, and sensing are comprehensively summarized. Special attention is paid to underwater scenarios considering the rapid development of marine explorations and the intrinsic properties of hydrophobic ionogels. Finally, the current challenges and immediate opportunities of this emerging yet fast-developing research field are discussed.

Ultralong Lifetime of Plasmon-Excited Electrons Realized in Nonepitaxial/Epitaxial Au@CdS/CsPbBr3 Triple-Heteronanocrystals.

Combination of the strong light-absorbing power of plasmonic metals with the superior charge carrier dynamics of halide perovskites is appealing for bio-inspired solar-energy conversion due to the potential to acquire long-lived plasmon-induced hot electrons. However, the direct coupling of these two materials, with Au/CsPbBr3 heteronanocrystals (HNCs) as a prototype, results in severe suppression of plasmon resonances. The present work shows that interfacial engineering is a key knob for overcoming this impediment, based on the creation of a CdS mediate layer between Au and CsPbBr3 forming atomically organized Au-CdS and CdS-CsPbBr3 interfaces by nonepitaxial/epitaxial combined strategy. Transient spectroscopy studies demonstrate that the resulting Au@CdS/CsPbBr3 HNCs generate remarkably long-lived plasmon-induced charge carriers with lifetime up to nanosecond timescale, which is several orders of magnitude longer than those reported for colloidal plasmonic metal-semiconductor systems. Such long-lived carriers extracted from plasmonic antennas enable to drive CO2 photoreduction with efficiency outperforming previously reported CsPbBr3 -based photocatalysts. The findings disclose a new paradigm for achieving much elongated time windows to harness the substantial energy of transient plasmons through realization of synergistic coupling of plasmonic metals and halide perovskites.

Mechanical Properties of High Temperature Vulcanized Silicone Rubber Aged in the Natural Environment.

Composite insulators operate in harsh field environments all year round. Their various properties and states of aging require attention. It is important to study the performance changes of composite insulator sheds after aging to evaluate the life of insulators operating on grids. For this reason, 22 composite insulator sheds from different factories, with different voltage levels and different ages years were selected to conduct mechanical properties testing. The mechanical properties include hardness, tensile strength, and elongation at break, and were investigated by thermogravimetric (TGA) testing, surface morphology, and nuclear magnetic resonance (NMR) characterization. The changes in mechanical properties of high temperature vulcanization (HTV) composite insulator silicone rubber aged in the natural environment were analyzed, including the reasons for these changes. The results showed that the transverse relaxation time T2 of the sample was closely related to its aging state. The more serious the silicone rubber's aging, the smaller was the T2. The state of the composite insulator can be evaluated by using T2 and aging years simultaneously. With the actual degree of aging in the silicone rubber intensified, its tensile strength and elongation at break generally showed a downward trend.

Synergistically Modulating Geometry and Electronic Structures of a Chalcogenide Photocatalyst via an Ion-Exchange Strategy.

Maneuvering the architecture and composition of semiconductors is essential to optimizing their performance in photocatalytic solar-to-fuel conversion. Here, we show that ion exchange, having a disparate mechanism with direct nucleation and growth of semiconductor crystals, can provide a new platform for rational control over the geometry and electronic structures of chalcogenide semiconductor photocatalysts. As a demonstration, the ZnSe nanocubes possessing a hollowed architecture and doped with a controllable amount of Ag+ ions are accessed via sequential ion exchange. The kinetics of the exchange reaction offers a knob for regulating the electronic structures of the Ag-doped ZnSe hollow cubes and, hence, their functions in light harvesting and photogenerated charge separation. Such synergistically geometric and optoelectronic modulation of ZnSe brings an order of magnitude enhancement in photocatalytic H2 evolution activity relative to commercial ZnSe powders. Our study corroborates that ion exchange may open up new horizons for judicious fabrication and engineering of semiconductor-based photocatalyst materials.

Simulation of the peel of hydrogels with stiff backing.

In this work, the peel of hydrogels under a stiff backing constraint was studied using a finite element method. The finite element method was first validated by comparing the simulation results to theoretical predictions and experimental measurements. Then, the method was used to investigate the effects of adhesion thickness, adhesion length and backing thickness on the peel behaviors, as well as the stress distribution within the adhesion layer. The results indicated that the peel force-displacement curve has a constant profile when the adhesion thickness and backing thickness are prescribed so long as the adhesion length is sufficiently long. The peak peel force increases with the adhesion length and then plateaus. The larger the intrinsic peak stress or the thicker the backing, the higher the plateau. The steady-state peel force is independent of the backing thickness, while positively correlated with the strain energy storage of the hydrogel adhesion layer. The critical vertical displacement corresponding to the peak peel force increases with the hydrogel thickness and decreases with the backing thickness. However, the critical vertical displacement corresponding to the steady-state peel force increases with the backing thickness. The present work puts forward an effective numerical approach to probe the peel of hydrogels, which is beneficial for the design of relevant structures.

Two-Dimensional All-in-One Sulfide Monolayers Driving Photocatalytic Overall Water Splitting.

For realizing scalable solar hydrogen synthesis, the development of visible-light-absorbing photocatalysts capable of overall water splitting is essential. Metal sulfides can capture visible light efficiently; however, their utilization in water splitting has long been plagued by the poor resilience against hole oxidation. Herein, we report that the ZnIn2S4 monolayers with dual defects (Ag dopants and nanoholes) accessed via cation exchange display stoichiometric H2 and O2 evolution in pure water under visible light irradiation. In-depth characterization and modeling disclose that the dual-defect structure endows the ZnIn2S4 monolayers with optimized light absorption and carrier dynamics. More significantly, the dual defects cooperatively function as active sites for water oxidation (Ag dopants) and reduction (nanoholes), thus leading to steady performance in photocatalytic overall water splitting without the assistance of cocatalysts. This work demonstrates a feasible way for fulfilling "all-in-one" photocatalyst design and manifests its great potential in addressing the stability issues associated with sulfide-based photocatalysts.

Positively charged collective oscillations induce efficient Aß1-42 fibril degradation in the presence of novel Au@Cu2-xS core/shell nanorods.

We synthesized Au@Cu2-xS core/shell nanorods (NRs) that have synergistic surface plasmon resonance (SPR) effects using a new cation exchange process in ethylene glycol (EG) phase. The dual effect - NIR photothermal and surface positive charge plasmon - of Au@Cu2-xS NRs, promote the capability to degrade Aß1-42 fibrils into amorphous protein.

Hybrid Plasmonic Nanodumbbells Engineering for Multi-Intensified Second Near-Infrared Light Induced Photodynamic Therapy.

Photodynamic therapy (PDT) has shown great potential in infection treatment. However, the shallow depth of the short wavelength light and the low reactive oxygen species (ROS) production hinder its development. A strategy that can achieve a second near-infrared (NIR-II) light that is a long wavelength induced multi-intensified antibacterial PDT is most critical. Herein, hybrid plasmonic Au/CdSexSy with precise Ag doping (ACA) nanodumbbells are rationally designed for ideal NIR-II light induced antibacterial PDT. Plasmonic Au nanorods extend the photocatalytic activity of ACA to NIR-II regions, which provides a basis for NIR-II light induced PDT. More importantly, multi-intensified PDT can be realized by the following creativities: (i) elaborate design of as-synthesized nanodumbbells that allows for electron holes to be redistributed in different regions simultaneously, (ii) the efficient hot-electrons injection that benefits from the ratio tailoring of anions ratio of Se and S, and (iii) the dopant Ag level inhibiting the combination of electron holes. The nanodumbbells create effective hot-electrons injection and a separation of electron holes, which provides great convenience for the production of ROS and allows NIR-II light induced PDT for the inhibition of bacteria and biofilms. As a result, comparably, our well-defined ACA hybrid nanodumbbells can generate about 40-fold superoxide radicals (·O2-) and more hydroxyl radicals (·OH). Therefore, the MIC value of the as-synthesized nanodumbbells is lower than the value of 1/16 of core-shell ACA. In vivo results further demonstrate that our nanodumbbells exhibit excellent PDT efficacy.

Highly Selective Photoreduction of CO2 with Suppressing H2 Evolution by Plasmonic Au/CdSe-Cu2 O Hierarchical Nanostructures under Visible Light.

Here, the photocatalytic CO2 reduction reaction (CO2 RR) with the selectivity of carbon products up to 100% is realized by completely suppressing the H2 evolution reaction under visible light (λ > 420 nm) irradiation. To target this, plasmonic Au/CdSe dumbbell nanorods enhance light harvesting and produce a plasmon-enhanced charge-rich environment; peripheral Cu2 O provides rich active sites for CO2 reduction and suppresses the hydrogen generation to improve the selectivity of carbon products. The middle CdSe serves as a bridge to transfer the photocharges. Based on synthesizing these Au/CdSe-Cu2 O hierarchical nanostructures (HNSs), efficient photoinduced electron/hole (e- /h+ ) separation and 100% of CO selectivity can be realized. Also, the 2e- /2H+ products of CO can be further enhanced and hydrogenated to effectively complete 8e- /8H+ reduction of CO2 to methane (CH4 ), where a sufficient CO concentration and the proton provided by H2 O reduction are indispensable. Under the optimum condition, the Au/CdSe-Cu2 O HNSs display high photocatalytic activity and stability, where the stable gas generation rates are 254 and 123 µmol g-1 h-1 for CO and CH4 over a 60 h period.

Atomically thin PdSeO3 nanosheets: a promising 2D photocatalyst produced by quaternary ammonium intercalation and exfoliation.

In 2018, the two-dimensional (2D) PdSeO3 monolayer was predicted to be a highly promising photocatalyst for direct overall water splitting in the light of density functional theory (DFT) computations. Herein, we present the first report on the synthesis of 2D PdSeO3 nanosheets by using the quaternary ammonium intercalation-assisted electrochemical exfoliation method. The resulting atomically thin PdSeO3 nanosheets possess a moderate band gap with suitable band edge alignments for water splitting, and display excellent activity and stability in photocatalytic H2 evolution.

Evolution of Hollow CuInS2 Nanododecahedrons via Kirkendall Effect Driven by Cation Exchange for Efficient Solar Water Splitting.

Hollow-structured semiconductor nanocrystals (NCs) have aroused tremendous research interest because of their compelling structure-related properties that can facilitate the development of many important applications including solar water splitting. However, the creation of multicomponent semiconductor NCs (such as I-III-VI2 and I2-II-IV-VI4 semiconductors) possessing a hollow architecture still remains a great challenge because of the difficulty in balancing the reactivities of multiple precursors. In this study, we report an effective strategy to prepare hollow CuInS2 nanododecahedrons featuring high uniformity in morphology and composition, based on the Kirkendall effect driven by the cation exchange between Cu+ and In3+ using Cu2-xS nanododecahedrons as templates. The unequal diffusion rates of cations result in an inward flux of vacancies favorably along the (0 16 0) facets of Cu2-xS dodecahedrons, forming a Cu2-xS@CuInS2 core-shell intermediate with striped voids in the core region. Optical absorption studies and photoelectrochemical measurements imply that the increase in the hollowing degree of the NCs benefits enhanced light harvesting and separation of photogenerated charge carriers. As a result, the obtained hollow CuInS2 nanododecahedrons present a high activity in photocatalytic hydrogen evolution, much superior to previously reported CuInS2 photocatalysts with different architectures. We envision that the multifarious morphologies attainable for the Cu2-xS NC templates and the advantages of Cu+ for cation exchange can make this method adaptable to a vast variety of previously intractable structures and compositions.

Long noncoding RNA POU3F3 promotes cancer cell proliferation in prostate carcinoma by upregulating rho-associated protein kinase 1.

Long noncoding RNAs (lncRNAs) POU3F3 is overexpressed in esophageal squamous-cell carcinomas, while its role in other human cancers is unclear. In this study we found that POU3F3 and rho-associated protein kinase 1 (ROCK1) were both increased in tumor tissues than in adjacent healthy tissues of patients with prostate carcinoma. Expression levels of POU3F3 increased with increase in the diameter of tumor but were not significantly affected by lymph node metastasis or distant metastasis. Expression levels of POU3F3 and ROCK1 were positive correlated in tumor tissues but not in adjacent healthy tissues. POU3F3 and ROCK1 overexpression promoted, while ROCK1 knockdown inhibited the proliferation of prostate carcinoma cells. ROCK1 knockdown reduced the enhancing effect of POU3F3 overexpression on cancer cell proliferation. POU3F3 overexpression led to ROCK1 overexpression in prostate carcinoma cells, while ROCK1 overexpression did not significantly affect POU3F3 expression. Therefore, lncRNA POU3F3 may promote cancer cell proliferation in prostate carcinoma by upregulating ROCK1.

Downregulation of lnRNA-NEF is involved in the postoperative cancer distant recurrence in prostate carcinoma patients.

LnRNA-NEF has characterized functionality only in liver cancer. In the present study, we observed that plasma lnRNA-NEF was downregulated, while plasma transforming growth factor-ß1 (TGF-ß1) was upregulated in patients with early-stage prostate carcinoma (PC) than in healthy controls. The levels of plasma lnRNA-NEF and plasma TGF-ß1 were inversely correlated in patients with PC but not in healthy controls. After surgical resection, the follow-up was performed for 5 years. It was observed that lnRNA-NEF was further decreased in patients with distant recurrence (DR), but not in patients with local recurrence and nonrecurrence. lnRNA-NEF overexpression caused inhibited TGF-ß1 expression in cells of PC cell lines, while TGF-ß1 overexpression failed to affect lnRNA-NEF expression. LnRNA-NEF overexpression inhibited, while the TGF-ß1 overexpression promoted the migration and invasion of cells of PC cell lines. TGF-ß1 overexpression partially rescued the inhibited migration and invasion of cells of PC cell lines caused by the lnRNA-NEF overexpression. Therefore, the downregulation of lnRNA-NEF may contribute to the postoperative DR in patients with PC through the interactions with TGF-ß1.

Phosphine ligand-mediated kinetics manipulation of aqueous cation exchange: a case study on the synthesis of Au@SnSx core-shell nanocrystals for photoelectrochemical water splitting.

Au@Sn2S3 and Au@SnS2 core-shell hybrid nanocrystals (HNCs) were respectively accessed via an aqueous cation exchange-mediated growth strategy by using different phosphine ligands. The choice of proper ligands during synthesis is imperative to optimize the photoelectrochemical performance of these previously hardly accessible HNCs that manifest compelling plasmon-exciton interactions.

Sumoylation Negatively Regulates CSR1-Dependent Prostate Cancer Cell Death.

BACKGROUND/AIMS: SUMOylation is a dynamic process and reversed by the activity of SUMO-specific proteases (SENPs) family. SENP1, a member of this family, is highly expressed and plays oncogenic roles in diverse cancers including prostate cancer. However, the SENP1-transgenic mice exhibit aberrant transformation of the mouse prostate gland but do not develop cancer. Cellular Stress Response 1 (CSR1) is a tumor suppressor gene and frequently deleted in prostate cancers. Overexpression of CSR1 in prostate cancer cells inhibits colony formation, anchorage-independent growth and induces cell death. METHODS: The relationship between CSR1 and SENP1 were determined by immunoprecipitation-based proteomics screen and verified by GST-pull down assay. In vivo SUMOylation assay was used to detect the direct effect of SENP1 in the regulation of CSR1. Clustered regularly interspaced short palindromic repeats (CRISPR)-based gene editing was used to generate Senp1-/- and CSR1-/- PC3 cells. FACS assay was used to determine the apoptosis ratio of cells after transfection. RESULTS: CSR1 is SUMOylated at K582 and rapid ubiquitinated and degradated in prostate cancer cells. SENP1 interacts with and deSUMOylates CSR1 to prevent its degradation and enhances CSR1-dependent prostate cancer cell death. CONCLUSION: Thus, our data indicates that CSR1 is a critical SUMOylated substrate of SENP1 that might partially explain the controversial roles of SENP1 in prostate cancer development.

Sleeve Gastrectomy Reversed Obesity-Induced Hypogonadism in a Rat Model by Regulating Inflammatory Responses in the Hypothalamus and Testis.

BACKGROUND: Obesity is a metabolic disease with a serious health burden in children and adults, and it induces a variety of conditions including subfecundity. Sleeve gastrectomy showed encouraging results in terms of weight loss and improve quality of life, and this study aimed to determine whether sleeve gastrectomy could reverse obesity-induced impaired fertility in male Sprague-Dawley rats. METHODS: After 16 weeks of a chow diet (CD) or a high-fat diet (HFD) challenge, rats on the HFD were given a sleeve gastrectomy or sham operation and then fed an HFD for another 8 weeks. Serum glucose, insulin, lipids, sex hormone, sperm quality, inflammatory profile of the testis, and hypothalamic Kiss1 expression in the three study groups were compared. RESULTS: Sleeve gastrectomy significantly decreased HFD-induced obesity and serum glucose and insulin levels. It also reversed the HFD-induced increase in teratozoospermia and decreases in sperm motility and progressive motility. Testicular morphological abnormalities were also improved after sleeve gastrectomy. Enzyme-linked immunosorbent assay showed that the expression of sex hormones increased after sleeve gastrectomy and that expression of inflammatory factors decreased. The HFD induced a hypothalamic inflammatory response that inhibited Kiss1 expression, which in turn mediated sex hormone expression. Sleeve gastrectomy treatment improved the hypothalamic response. CONCLUSIONS: The results consistently showed that sleeve gastrectomy reversed obesity-induced male fertility impairment by decreasing the inflammatory responses of the testis and hypothalamus.

Colloid-Interface-Assisted Laser Irradiation of Nanocrystals Superlattices to be Scalable Plasmonic Superstructures with Novel Activities.

High-efficient charge and energy transfer between nanocrystals (NCs) in a bottom-up assembly are hard to achieve, resulting in an obstacle in application. Instead of the ligands exchange strategies, the advantage of a continuous laser is taken with optimal wavelength and power to irradiate the film-scale NCs superlattices at solid-liquid interfaces. Owing to the Au-based NCs' surface plasmon resonance (SPR) effect, the gentle laser irradiation leads the Au NCs or Au@CdS core/shell NCs to attach each other with controlled pattern at the interfaces between solid NCs phase and liquid ethanol/ethylene glycol. A continuous wave 532 nm laser (6.68-13.37 W cm-2 ), to control Au-based superlattices, is used to form the monolayer with uniformly reduced interparticle distance followed by welded superstructures. Considering the size effect to Au NCs' melting, when decreasing the Au NCs size to ≈5 nm, stronger welding nanostructures are obtained with diverse unprecedented shapes which cannot be achieved by normal colloidal synthesis. With the help of facile scale-up and formation at solid-liquid interfaces, and a good connection of crystalline between NCs, the obtained plasmonic superstructured films that could be facilely transferred onto different substrates exhibit broad SPR absorption in the visible and near-infrared regime, enhanced electric conductivities, and wide applications as surface enhanced Raman scattering (SERS)-active substrates.

Buckling-driven self-assembly of self-similar inspired micro/nanofibers for ultra-stretchable electronics.

Self-similar structures are capable of highly enhancing the deformability of stretchable electronics. We presented a self-assembly method based on the tunable buckling of serpentine fiber-based interconnects (FiberBIs), which are deposited using our presented helix electrohydrodynamic printing (HE-printing) technique, to fabricate self-similar structures with enhanced stretchability (up to 250%). It provides a low-cost, printing-based approach for the generation of large-scale self-similar FiberBIs. Distinct buckling behaviors and modes occur under specific conditions. To elucidate the mechanics governing this phenomenon, we present detailed experimental and theoretical studies of the buckling mechanics of serpentine microfibers on compliant substrates. Firstly, the effect of the magnitude and direction of prestrain on the buckling behavior of a fiber-on-substrate is discussed. Secondly, the critical geometry of a serpentine fiber as a key parameter for fabricating uniform self-similar fibers is also figured out. Finally, the cross-sectional geometry of the fiber as a judgment criterion for determining the in-surface or out-of-surface buckling of the fiber is established. The investigation can guide the fabrication process of large-scale self-similar structures for high-performance electronic devices with extreme stretchability.