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Investigating interface engineering by piezoelectric, flexoelectric and ferroelectric polarizations in semiconductor devices is important for their applications in electronics, optoelectronics, catalysis and many more. The interface engineering by polarizations strongly depends on the property of interface barrier. However, the fixed value and uncontrollability of interface barrier once it is constructed limit the performance and application scenarios of interface engineering by polarizations. Here, we report a strategy of tuning piezotronic effect (interface barrier and transport controlled by piezoelectric polarization) reversibly and accurately by electric pulse. Our results show that for Ag/HfO2/n-ZnO piezotronic tunneling junction, the interface barrier height can be reversibly tuned as high as 168.11 meV by electric pulse, and the strain (0–1.34‰) modulated current range by piezotronic effect can be switched from 0–18 nA to 44–72 nA. Moreover, piezotronic modification on interface barrier tuned by electric pulse can be up to 148.81 meV under a strain of 1.34‰, which can totally switch the piezotronic performance of the electronics. This study provides opportunities to achieve reversible control of piezotronics, and extend them to a wider range of scenarios and be better suitable for micro/nano-electromechanical systems. Interface engineering by local polarization is becoming increasingly important for tunable electronics. Here, authors demonstrate an electric pulse-tuned piezotronic effect in Ag/HfO2/n-ZnO junction, enabling reversible and accurate regulation of barrier height and piezotronic modification range. [ABSTRACT FROM AUTHOR]

Mechanical sensors are mainly divided into two types (vertical force sensing and lateral strain sensing). Up to now, one sensor with two working modes is still a challenge. Here, we demonstrate a structural design concept combing a piezoelectric nano/microwire with a flexible polymer with protrusions that enables a dual-modal piezotronic transistor (DPT) with two working modes for highly sensitive vertical force sensing and lateral strain sensing. For vertical force sensing, DPT exhibits a force sensitivity up to 221.5 N−1 and a minimum identifiable force down to 21 mN, corresponding to a pressure sensitivity of 1.759 eV/MPa. For lateral strain sensing, DPT can respond to a large compression strain (~5.8%) with an on/off ratio up to 386.57 and a gauge factor up to 8988.6. It is a universal design that can integrate vertical force sensing and lateral strain sensing into only one nanodevice, providing a feasible strategy for multimodal devices. Developing mechanical sensors with two working modes for detecting vertical force and lateral strain is challenging. Here, Ge et al. report a piezotronic transistor with protrusions that enable dual-modal functionality and improve sensing performance. [ABSTRACT FROM AUTHOR]

Piezotronics with capacity of constructing adaptive and seamless interactions between electronics/machines and human/ambient are of value in Internet of Things, artificial intelligence and biomedical engineering. Here, we report a kind of highly sensitive strain sensor based on piezotronic tunneling junction (Ag/HfO2/n-ZnO), which utilizes the strain-induced piezoelectric potential to control the tunneling barrier height and width in parallel, and hence to synergistically modulate the electrical transport process. The piezotronic tunneling strain sensor has a high on/off ratio of 478.4 and high gauge factor of 4.8 × 105 at the strain of 0.10%, which is more than 17.8 times larger than that of a conventional Schottky-barrier based strain sensor in control group as well as some existing ZnO nanowire or nanobelt based sensors. This work provides in-depth understanding for the basic mechanism of piezotronic modulation on tunneling junction, and realizes the highly sensitive strain sensor of piezotronic tunneling junction on device scale, which has great potential in advanced micro/nano-electromechanical devices and systems. Strain-induced piezoelectric polarization can be used to modulate the interface electrical transport. Here, the authors achieved a piezotronic tunneling strain sensor at device scale with optimized performance based on the structure of Ag/HfO2/n-ZnO. [ABSTRACT FROM AUTHOR]

Piezotronics with capacity of constructing adaptive and seamless interactions between electronics/machines and human/ambient are of value in Internet of Things, artificial intelligence and biomedical engineering. Here, we report a kind of highly sensitive strain sensor based on piezotronic tunneling junction (Ag/HfO2/n-ZnO), which utilizes the strain-induced piezoelectric potential to control the tunneling barrier height and width in parallel, and hence to synergistically modulate the electrical transport process. The piezotronic tunneling strain sensor has a high on/off ratio of 478.4 and high gauge factor of 4.8 × 105 at the strain of 0.10%, which is more than 17.8 times larger than that of a conventional Schottky-barrier based strain sensor in control group as well as some existing ZnO nanowire or nanobelt based sensors. This work provides in-depth understanding for the basic mechanism of piezotronic modulation on tunneling junction, and realizes the highly sensitive strain sensor of piezotronic tunneling junction on device scale, which has great potential in advanced micro/nano-electromechanical devices and systems. Strain-induced piezoelectric polarization can be used to modulate the interface electrical transport. Here, the authors achieved a piezotronic tunneling strain sensor at device scale with optimized performance based on the structure of Ag/HfO2/n-ZnO. [ABSTRACT FROM AUTHOR]

The high‐temperature rise of rotor permanent magnet (PM) in high‐speed PM machine (HSPMM) is one of the main bottlenecks that limits the development of HSPMM. The main reason for the increase of the PM temperature is the eddy current loss caused by high‐frequency harmonics. In this study, a new type of composite magnetic material is studied, which greatly reduces the electrical conductivity of the PM and thus reduces the eddy current loss under the condition of ensuring the magnetic properties. The electrical conductivity of magnetic powder composites is calculated by introducing the improved effective medium model of the magnetic powder packing coefficient. Through the calculation of the porosity of the magnetic powder composite, the effects of the particle size, gradation and shape of the magnetic powder on the electrical conductivity of the composite were obtained. The model solves the problem of calculating the electrical conductivity of the powder structure composite rotor in eddy current loss calculation. The accuracy of the calculation is verified by the four‐probe method, which provides guidance for the design of a composite rotor HSPMM. [ABSTRACT FROM AUTHOR]

Background: Glioblastoma multiforme (GBM) is the most common and aggressive primary malignant brain tumor with grim prognosis. Aberrant DNA methylation is an epigenetic mechanism that promotes GBM carcinogenesis, while the function of DNA methylation at enhancer regions in GBM remains poorly described. Results: We integrated multi-omics data to identify differential methylation enhancer region (DMER)-genes and revealed global enhancer hypomethylation in GBM. In addition, a DMER-mediated target genes regulatory network and functional enrichment analysis of target genes that might be regulated by hypomethylation enhancer regions showed that aberrant enhancer regions could contribute to tumorigenesis and progression in GBM. Further, we identified 22 modules in which lncRNAs and mRNAs synergistically competed with each other. Finally, through the construction of drug-target association networks, our study identified potential small-molecule drugs for GBM treatment. Conclusions: Our study provides novel insights for understanding the regulation of aberrant enhancer region methylation and developing methylation-based biomarkers for the diagnosis and treatment of GBM. [ABSTRACT FROM AUTHOR]

Utilizing inner‐crystal piezoelectric polarization charges to control carrier transport across a metal‐semiconductor or semiconductor–semiconductor interface, piezotronic effect has great potential applications in smart micro/nano‐electromechanical system (MEMS/NEMS), human‐machine interfacing, and nanorobotics. However, current research on piezotronics has mainly focused on systems with only one or rather limited interfaces. Here, the statistical piezotronic effect is reported in ZnO bulk composited of nanoplatelets, of which the strain/stress‐induced piezo‐potential at the crystals' interfaces can effectively gate the electrical transport of ZnO bulk. It is a statistical phenomenon of piezotronic modification of large numbers of interfaces, and the crystal orientation of inner ZnO nanoplatelets strongly influence the transport property of ZnO bulk. With optimum preferred orientation of ZnO nanoplatelets, the bulk exhibits an increased conductivity with decreasing stress at a high pressure range of 200–400 MPa, which has not been observed previously in bulk. A maximum sensitivity of 1.149 µS m−1 MPa−1 and a corresponding gauge factor of 467–589 have been achieved. As a statistical phenomenon of many piezotronic interfaces modulation, the proposed statistical piezotronic effect extends the connotation of piezotronics and promotes its practical applications in intelligent sensing. [ABSTRACT FROM AUTHOR]

Utilizing inner‐crystal piezoelectric polarization charges to control carrier transport across a metal‐semiconductor or semiconductor–semiconductor interface, piezotronic effect has great potential applications in smart micro/nano‐electromechanical system (MEMS/NEMS), human‐machine interfacing, and nanorobotics. However, current research on piezotronics has mainly focused on systems with only one or rather limited interfaces. Here, the statistical piezotronic effect is reported in ZnO bulk composited of nanoplatelets, of which the strain/stress‐induced piezo‐potential at the crystals’ interfaces can effectively gate the electrical transport of ZnO bulk. It is a statistical phenomenon of piezotronic modification of large numbers of interfaces, and the crystal orientation of inner ZnO nanoplatelets strongly influence the transport property of ZnO bulk. With optimum preferred orientation of ZnO nanoplatelets, the bulk exhibits an increased conductivity with decreasing stress at a high pressure range of 200–400 MPa, which has not been observed previously in bulk. A maximum sensitivity of 1.149 µS m−1 MPa−1 and a corresponding gauge factor of 467–589 have been achieved. As a statistical phenomenon of many piezotronic interfaces modulation, the proposed statistical piezotronic effect extends the connotation of piezotronics and promotes its practical applications in intelligent sensing.A statistical piezotronic effect is proposed in ZnO bulk composed of c‐axis preferentially oriented nanoplatelets. It is a statistical phenomenon of piezotronic modification of large numbers of interfaces. High sensitivity and gauge factor at a high‐pressure range of 200–400 MPa are achieved in the ZnO bulk. The statistical piezotronic effect extends the connotation of piezotronics and promotes its practical applications. [ABSTRACT FROM AUTHOR]

Background: Increasing morbidity and misdiagnosis of vestibular migraine (VM) gravely affect the treatment of the disease as well as the patients' quality of life. A powerful diagnostic prediction model is of great importance for management of the disease in the clinical setting. Materials and Methods: Patients with a main complaint of dizziness were invited to join this prospective study. The diagnosis of VM was made according to the International Classification of Headache Disorders. Study variables were collected from a rigorous questionnaire survey, clinical evaluation, and laboratory tests for the development of a novel predictive diagnosis model for VM. Results: A total of 235 patients were included in this study: 73 were diagnosed with VM and 162 were diagnosed with non-VM vertigo. Compared with non-VM vertigo patients, serum magnesium levels in VM patients were lower. Following the logistic regression analysis of risk factors, a predictive model was developed based on 6 variables: age, sex, autonomic symptoms, hypertension, cognitive impairment, and serum Mg2+ concentration. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve was 0.856, which was better than some of the reported predictive models. Conclusion: With high sensitivity and specificity, the proposed logistic model has a very good predictive capability for the diagnosis of VM. It can be used as a screening tool as well as a complementary diagnostic tool for primary care providers and other clinicians who are non-experts of VM. [ABSTRACT FROM AUTHOR]

The rate of hyperglycaemia in people around the world is increasing at an alarming rate at present, and innovative methods of alleviating hyperglycaemia are needed. The effects of Jerusalem artichoke inulin on hyperglycaemia, liver-related genes and the intestinal microbiota in mice fed a high-fat diet (HFD) and treated with streptozotocin (STZ) to induce hyperglycaemia were investigated. Inulin-treated hyperglycaemic mice had decreased average daily food consumption, body weight, average daily water consumption and relative liver weight and blood concentrations of TAG, total cholesterol, HDL-cholesterol and fasting blood glucose. Liver-related gene expressions in hyperglycaemic (HFD-fed and STZ-treated) compared with control mice showed eighty-four differentially expressed genes (forty-nine up-regulated and thirty-five down-regulated). In contrast, hyperglycaemic mice treated with inulin had twenty-two differentially expressed genes compared with control ones. Using Illumina high-throughput sequencing technology, the rarefaction and the rank abundance curves as well as the α diversity indices showed the treatment-induced differences in bacterial diversity in intestine. The linear discriminant analysis of effect size showed that the inulin treatment improved intestinal microbiota; in particular, it significantly increased the number of Bacteroides in the intestine of mice. In conclusion, inulin is potentially an effective functional food for the prevention and/or treatment of hyperglycaemia. [ABSTRACT FROM AUTHOR]

The cheap, environment‐friendly and renewable biomass is a promising raw material to prepare the carbon‐based composites for the lithium‐ion batteries. Herein, the loofah sponge‐derived hollow carbon fibers (LDHCF) were obtained by the activation and carbonization process of biomass loofah sponges. The LDHCF with the porous structure shows the high surface area and active sites. When LDHCF were coated with SnO2 nanoparticles via the hydrothermal method, the SnO2/LDHCF composite as anode material exhibits a reversible capacity of 562.1 mAh g−1 at 0.2 A g−1 after 100 cycles and the columbic efficiency is 99.0% due to the good conductivity, buffer effect of LDHCF, and high theoretical specific capacity of SnO2. Such the structure not only proves a novel high‐quality carbon template/matrix, but also provides a preferable way to make sustainable anodes in electrochemical energy storage and economical multi‐functional carbon‐based hybrids available for other practical applications. Herein, we demonstrate that the good rate capability, and excellent long cycling performance of the biomass‐based SnO2/LDHCF (loofah sponge‐derived hollow carbon fibers) composite was fabricated via the hydrothermal treatment and carbonization process. The SnO2/LDHCF composite as anode material for LIBs exhibits a reversible capacity of 562.1 mAh g−1 at 0.2 A g−1 after 100 cycles and the columbic efficiency is 99.0%. [ABSTRACT FROM AUTHOR]

Due to the high specific capacities and environmental benignity, lithium-sulfur (Li-S) batteries have shown fascinating potential to replace the currently dominant Li-ion batteries to power portable electronics and electric vehicles. However, the shuttling effect caused by the dissolution of polysulfides seriously degrades their electrochemical performance. In this paper, Mn2O3 microcubes are fabricated to serve as the sulfur host, on top of which Al2O3 layers of 2 nm in thickness are deposited via atomic layer deposition (ALD) to form Mn2O3/S (MOS) @Al2O3 composite electrodes. The MOS@Al2O3 electrode delivers an excellent initial capacity of 1012.1 mAh g−1 and a capacity retention of 78.6% after 200 cycles at 0.5 C, and its coulombic efficiency reaches nearly 99%, giving rise to much better performance than the neat MOS electrode. These findings demonstrate the double confinement effect of the composite electrode in that both the porous Mn2O3 structure and the atomic Al2O3 layer serve as the spacious host and the protection layer of sulfur active materials, respectively, for significantly improved electrochemical performance of the Li-S battery. [ABSTRACT FROM AUTHOR]

MnMoO4 nanotubes of diameter about 120 nm were successfully synthesized by a single-spinneret electrospinning technique followed by calcination in air, and their structural, morphological, and electrochemical properties were studied with the aim to fabricate high-performance supercapacitor devices. The obtained MnMoO4 nanotubes display a 1D architecture with a porous structure and hollow interiors. Benefiting from intriguing structural features, the unique MnMoO4 nanotube electrodes exhibit a high specific capacitance, excellent rate capability, and cycling stability. As an example, the tube-like MnMoO4 delivers a specific capacitance of 620 F g−1 at a current density of 1 A g−1, and 460 F g−1 even at a very high current density of 60 A g−1. Remarkably, almost no decay in specific capacitance is found after continuous charge/discharge cycling for 10,000 cycles at 1 A g−1. An asymmetric supercapacitor fabricated from this MnMoO4 nanotubes and activated carbon displayed a maximum high energy density of 31.7 Wh kg−1 and a power density of 797 W kg−1, demonstrating a good prospect for practical applications in energy storage electronics. [ABSTRACT FROM AUTHOR]

Composites consisting of selenium/carbon (Se/C) encapsulated by ultra-thin Ni(OH) nanosheet shell are synthesized as cathode for high-performance lithium-selenium batteries. The Se/C-Ni(OH) cathode presents excellent discharge capacities and cyclic stability with almost 100% Coulombic efficiencies. It delivers a reversible capacity of 323 mAh g after 300 cycles with almost negligible capacity degradation after 100 cycles at a high current density of 1 C. Several unique functional features of the composite electrodes are responsible for the findings. The uniform mixture of Se and carbon black in the composite promotes the utilization of the active materials with enhanced ion/electron transfer. The Ni(OH) nanosheets maintain the integrity of Se/C core during cycles, reducing the shuttling effect reactions of polyselenides. These results demonstrate that the Se/C-Ni(OH) composite cathode is a promising candidate for application in rechargeable lithium-selenium batteries. [ABSTRACT FROM AUTHOR]

Flexible and easily reconfigurable supercapacitors show great promise for application in wearable electronics. In this study, multiwall C nanotubes (CNTs) decorated with hierarchical ultrathin zinc sulfide (ZnS) nanosheets (ZnS@CNT) are synthesized via a facile method. The resulting ZnS@CNT electrode, which delivers a high specific capacitance of 347.3 F·g and an excellent cycling stability, can function as a high-performance electrode for a flexible all-solid-state supercapacitor using a polymer gel electrolyte. Our device exhibits a remarkable specific capacitance of 159.6 F·g, a high energy density of 22.3 W·h·kg, and a power density of 5 kW·kg. It also has high electrochemical performance even under bending or twisting. The all-solid-state supercapacitors can be easily integrated in series to power different commercial light-emitting diodes without an external bias voltage. [ABSTRACT FROM AUTHOR]

The holothurian-like γ-MnS/carbon nanotube (CNT) nanocomposites are successfully fabricated through a facile two-step hydrothermal method. The γ-MnS@CNT hybrid nanocomposite is an attractive electrode material for supercapacitors as it exhibits excellent electrochemical performance with a high specific capacitance of 641.9 F g−1 and cyclic stability of 94.6 % retention after 3000 cycles at a current density of 0.5 A g−1, which are superior to those of CNTs and pure γ-MnS nanoparticles. Furthermore, the as-fabricated all-solid-state supercapacitor reveals remarkable specific capacitance of 263.5 F g−1, high capacitance retention, and a high energy density of 36.6 Wh kg−1 at a power density of 0.5 kW kg−1. The device maintains its supercapacitor performance well, even under bending or twisting states, indicating the excellent mechanical stability and flexibility of the device. The impressive results demonstrate the great opportunity for practical application of this metal sulfide-based composite in high-performance, flexible energy storage devices and wearable electronics. [ABSTRACT FROM AUTHOR]

Hierarchical mesoporous core–shell CoMn2O4@MnO2 nanoneedle arrays on nickel foam have been manufactured via a two-step hydrothermal process. Electrochemical performances of the CoMn2O4@MnO2 nanomaterials have been tested for supercapacitors and demonstrated outstanding properties. The CoMn2O4@MnO2 electrode delivers a specific capacitance of 2126 F g−1 at a current density of 1 A g−1 in 2 M KOH aqueous solution and also shows an excellent cycling stability, which retains 94.4% of the initial capacitance after 5000 charge/discharge cycles at a current density of 4 A g−1. The result confirms the superiority of the CoMn2O4@MnO2 electrode compared with the CoMn2O4 electrode and demonstrates the potential application of the CoMn2O4@MnO2 nanoneedle array electrode for high-performance energy storage device applications. [ABSTRACT FROM AUTHOR]

Design and control over the growth of novel nanomaterial for flexible electrode are significant and practical for the study of portable energy storage devices. Herein, the flexible all-solid-state charge-storage devices assembled by the hierarchical CoMnO nanoneedle array on the Ni foam electrode have been designed and manufactured. The CoMnO electrode is prepared via a hydrothermal process and subsequent annealing treatment. The CoMnO electrode has a high-power battery-type behavior with a capacity of 223 mAh g at a discharge current density of 1 A g in a three-electrode system. When applied in the flexible all-solid-state charge-storage device, it displays a satisfactory capacity of 46 mAh g at a discharge current density of 1 A g, an energy density of 23.29 Wh kg at a power density of 0.5 kW kg and a power density of 4 kW kg at an energy density of 12 Wh kg. About 80.3% of the initial capacity is achieved after 5000 charge/discharge cycles at a current density of 4 A g, which shows the excellent cycling stability of the device. This work demonstrates the potential application of the CoMnO nanoneedle array electrode for high-performance flexible charge-storage devices. [ABSTRACT FROM AUTHOR]

Hyperbaric oxygen (HBO) therapy through breathing oxygen at the pressure of above 1 atmosphere absolute (ATA) is useful for varieties of clinical conditions, especially hypoxic-ischemic diseases. Because of generation of reactive oxygen species (ROS), breathing oxygen gas at high pressures can cause oxygen toxicity in the central nervous system, leading to multiple neurological dysfunction, which limits the use of HBO therapy. Studies have shown that Hydrogen gas (H2) can diminish oxidative stress and effectively reduce active ROS associated with diseases. However, the effect of H2 on ROS generated from HBO therapy remains unclear. In this study, we investigated the effect of H2 on ROS during HBO therapy using PC12 cells. PC12 cells cultured in medium were exposed to oxygen gas or mixed oxygen gas and H2 at 1 ATA or 5 ATA. Cells viability and oxidation products and ROS were determined. The data showed that H2 promoted the cell viability and inhibited the damage in the cell and mitochondria membrane, reduced the levels of lipid peroxidation and DNA oxidation, and selectively decreased the levels of •OH but not disturbing the levels of O2•-, H2O2, or NO• in PC12 cells during HBO therapy. These results indicated that H2 effectively reduced •OH, protected cells against oxygen toxicity resulting from HBO therapy, and had no effect on other ROS. Our data supported that H2 could be potentially used as an antioxidant during HBO therapy. [ABSTRACT FROM AUTHOR]

Using two series of de novo designed antimicrobial peptides, we studied the effects of peptide length and hydrophobicity/charge (H/C) ratio on the antimicrobial activities. For these peptides, a correlation was established between their antimicrobial efficacy and the leakage, aggregation, and fusion activities on artificial membrane. The results showed that peptides with an H/C ratio of 1.3, and a length of about half of the membrane thickness caused most potent membrane leakage, and negligible membrane aggregation and fusion. In addition, such peptide also exhibited the highest antimicrobial activity. Analysis of the hydrophobic and electrostatic interactions showed that the strength, the order and the position of these interactions determined the activities of the peptides on the artificial membrane and thus the antimicrobial efficacy. Further analyses on the tilt angle of the peptides on the membrane surface indicated that the peptides distorted the membrane in a dynamic mode, instead of being fixed in the membrane at a constant angle. [ABSTRACT FROM AUTHOR]

Hierarchical-structured copper sulfide nanoneedles were grown on multi-walled carbon nanotube backbone (denoted as CuS@CNT) as electrodes for supercapacitors via a facile template-based hydrothermal conversion approach and further by simply impregnating sulfur into CuS@CNT (S@CuS@CNT) as electrodes for Li-S batteries. The electrochemical measurements showed that the resultant CuS@CNT composite electrodes deliver outstanding electrochemical performance with a specific capacitance up to 566.4 F g and cyclic stability of 94.5 % of its initial capacitance after 5000 cycles at a current density of 1 A g. A synergistic effect arising from the unique hierarchical structure was responsible for the electrode performance, including a large surface area of 49.3 m g and active CuS ultrafine nanoneedles firmly bonded to the highly conductive carbon nanotube (CNT) backbone. When used as an electrode material for Li-S batteries, the S@CuS@CNT (S content 59 wt%) exhibited satisfying electrochemical performance. The S@CuS@CNT electrode showed that coulombic efficiency was close to 100 % and capacity maintained more than 500 mA h g with progressive cycling up to more than 100 cycles even at a high current density. This strategy of stabilizing S with a small amount of copper sulfide nanoneedles can be a very promising method to prepare free-standing cathode material for high-performance Li-S batteries. The fabrication strategy presented here is low cost, facile, and scalable, which can be considered as a promising material for large-scale energy storage device. In particular, the use of CNT as backbone for the growth of active materials presents many potential merits owing to its lightweight, biodegradable, and stretchable characteristics. [ABSTRACT FROM AUTHOR]

A 3-D porous metal–organic framework [Cu(SiF6)(4,4′-bpy)2] was reported to have high methane storage. The studies about [Cu(SiF6)(4,4′-bpy)2] were only related with methane storage but information on detailed synthesis and characterization as well as adsorption properties of [Cu(SiF6)(4,4′-bpy)2], especially the H2 and CO2 adsorption properties, was scarce. In this work, [Cu(SiF6)(4,4′-bpy)2] has been synthesized by adjusting the molar ratio of the reagents, synthesis temperature, and crystallization time. This method for obtaining [Cu(SiF6)(4,4′-bpy)2] at low temperature has not been reported before. Temperature played an important role in synthesis of the sample and low temperature was beneficial for synthesizing bigger sample. Adsorption isotherms for carbon dioxide and hydrogen were measured under high pressure. [Cu(SiF6)(4,4′-bpy)2] exhibited H2 storage up to 2.36 wt% at 18 bar and a high CO2 capture up to 4.17 mmol g−1 at 298 K at 10 bar. [ABSTRACT FROM PUBLISHER]

Objective: To evaluate the therapeutic effect and the oxidative stress effect of 9 and 18 hour hyperbaric oxygenation therapy (HBOT) protocols on the earliest stage of acute permanent middle cerebral artery occlusion (MCAO) in rats. Methods: The permanent MCAO model of rats was used. The animals were randomly divided into 9 and 18 hour HBOT groups, as well as a control group. Main outcome measures: (1) The Garcia neurological grading system was used to assess the therapeutic effect of hyperbaric oxygenation therapy; (2) the infarct volume was calculated with the 2,3,5-triphenyltetrazolium chloride (TTC) pathologic staining and NIH Image J software 24 and 120 hours after MCAO; (3) the level of reactive oxygen species determined by superoxide dismutase (SOD), malondialdehyde (MDA) and nitric oxide (NO) in ischemic brain tissue were separately examined at the 18, 48 and 120 hour post-ischemia time points using spectrophotometry. Results: (1) There were significant improvements in the neurobehavioral outcome of the rats in the 9 and the 18 hour groups, as compared with rats from the control group (p<0.01); (2) cerebral infarct volume decreased 63–64% in the rats of 9 hour group and 51–66% in the 18 hour group at the 24 and 120 hour time points, as compared with that of the control group; (3) the SOD levels of the 9 and 18 hour groups were remarkably lower than those of control group after both 18 and 48 hours (p<0.01 and p<0.05); (4) the MDA level of the 9 and 18 hour groups were both remarkably lower than the control groups, especially at 18 hours (p<0.05). Meanwhile, the MDA level in the 9 hour group was remarkably lower than both the 18 hour group and the control group (p<0.01 and p<0.05); (5) the level of NO in both hyperbaric oxygenation therapy groups were remarkably higher than that of the control at 18 and 48 hour time points (p<0.01). While the level in 18 hour group was remarkably lower than that of 9 hour group at 18 hour time point (p<0.05). At the 120 hour mark, the NO levels were basically the same in all the three groups. Conclusions: (1) The two protocols of large dose hyperbaric oxygenation therapy are highly efficient in reducing infarct volume and improving neurobehavioral outcome in permanent MCAO rats within the earliest stages of stroke; (2) increased duration of hyperbaric oxygenation therapy does not appear to equate to improved outcomes; in fact, the longer duration may aggravate the oxidative stress in ischemic tissue. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries are promising energy storage systems due to their large theoretical energy density of 2600 Wh kg−1 and cost effectiveness. However, the severe shuttle effect of soluble lithium polysulfide intermediates (LiPSs) and sluggish redox kinetics during the cycling process cause low sulfur utilization, rapid capacity fading, and a low coulombic efficiency. Here, a 3D copper, nitrogen co‐doped hierarchically porous graphitic carbon network developed through a freeze‐drying method (denoted as 3D Cu@NC‐F) is prepared, and it possesses strong chemical absorption and electrocatalytic conversion activity for LiPSs as highly efficient sulfur host materials in Li–S batteries. The porous carbon network consisting of 2D cross‐linked ultrathin carbon nanosheets provides void space to accommodate volumetric expansion upon lithiation, while the Cu, N‐doping effect plays a critical role for the confinement of polysulfides through chemical bonding. In addition, after sulfuration of Cu@NC‐F network, the in situ grown copper sulfide (CuxS) embedded within CuxS@NC/S‐F composite catalyzes LiPSs conversion during reversible cycling, resulting in low polarization and fast redox reaction kinetics. At a current density of 0.1 C, the CuxS@NC/S‐F composites' electrode exhibits an initial capacity of 1432 mAh g−1 and maintains 1169 mAh g−1 after 120 cycles, with a coulombic efficiency of nearly 100%. An in situ grown copper sulfide (CuxS) embedded within a 3D CuxS@NC/S‐F composite not only dynamically promotes the electrochemical reaction kinetics of LiPSs and reduces the polarization inside Li‐S batteries, but also contributes to the capacity by the electrochemical reaction. The elaborate structure design and rational heteroatomic doping play crucial roles in achieving high capacity and long‐term cycling in Li–S batteries. [ABSTRACT FROM AUTHOR]