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The review article describes the recent progress on SiC single-crystal and epitaxial growth technology. SiC is a third-generation semiconducting material with wide bandgap and high electrical breakdown field. Thanks to its excellent properties, it becomes an advantageous material in the field of high-temperature and high-power electronic device applications. Power devices fabricated of SiC are able to be operated at higher power density and higher switching frequency. This review focus on the growth, doping control and defect control of SiC single-crystal ingot and epilayer. The process of PVT, CVD, defect control, doping control and some recent applications of SiC are described. Various types of defects are described, including Micropipes, Dislocations, Stacking Faults etc. The wafering and polishing technology are also described.

A cobalt (Co)-doped perovskite molybdenum trioxide (α-MoO

With the increased development of wearable electronics, flexible zinc ion batteries (ZIBs) have attracted widespread attention owing to their low cost, superior safety, and simple fabrication process. Nevertheless, the limited active mass loading and low specific capacity remain challenges to be overcome. Herein, an effective in situ growth strategy is used to boost the mass loading and specific capacity of flexible ZIBs. We employed a mussel-derived polydopamine layer as an inductive catalyst to prompt the growth of flower-like δ-MnO2 on carbon cloth, which demonstrated strong adhesion to the surface, high mass loading, and excellent flexibility. In addition, the formed 3D conductive and supporting networks contribute to the realization of superior long cycle life, as well as a high specific capacity. As a result, the as-obtained flexible cathode can achieve a high initial discharge capacity of 1.3 mA h cm−2 at a current density of 1 mA cm−2 and a reversible capacity of 0.25 mA h cm−2 at 10 mA cm−2 for 10 000 cycles. Moreover, its reaction mechanism in ZIBs was analyzed via a series of ex situ characterization techniques, and the results suggest that the charge–discharge behavior is determined based on the Zn2+ (de-)intercalation in the δ-MnO2 interlayer. Remarkably, the as-developed flexible cathode is assembled into a flexible quasi-solid-state device, which shows excellent flexibility and can easily power one LED-based device, which has significant application prospects in wearable electronics. This work provides a novel tactic for the design of flexible batteries with high active mass loading and excellent electrochemical performance via employing polydopamine as an inductive catalyst.

Rational materials design for the synthesis of desirable hollow micro- and nanostructures has recently revealed the remarkable potential for high-performance energy storage and conversion devices. Owing to their unique "core-void-shell" structural configurations, yolk-shell-structured electrode materials can achieve intimate contact with the electrolyte and alleviate the volume expansion issue during electrochemical cycling, which is therefore poised to further boost the electrochemical properties of hybrid supercapacitors. Herein, a facile self-templated strategy, consisting of a hydrothermal step and a high-temperature sulfurization process, has been developed for the construction of yolk-shell (NiCo)9S8 spheres in situ coated by graphite carbon ((NiCo)9S8/GC) due to the non-equilibrium thermal treatment of alkali metal alkoxides. The as-synthesized yolk-shelled sphere exhibits a high specific capacitance of 1434.4 F g-1 (179.3 mA h g-1) at a current density of 1 A g-1, and good rate capability and cycling stability with 83.1% capacitance retention at 8 A g-1 over 5000 cycles. To further demonstrate its practical application, a hybrid supercapacitor device was assembled using (NiCo)9S8/GC as the battery-type positive electrode and activated carbon (AC) as the capacitive-type electrode. The as-fabricated device can reach a wide voltage window of up to 1.6 V, deliver a high energy density of 55.6 W h kg-1 at a power density of 800.3 W kg-1 and maintain 90.2% of specific capacitance after 3000 cycles.

Objective Minimally invasive surgery (MIS), or percutaneous, lumbar pedicle screw placement is commonly done, but the percutaneous nature of this makes posterior arthrodesis extremely difficult. Many times, surgeons will simply forego posterior arthrodesis, place posterior pedicle screws, and rely only on the interbody area for arthrodesis. We describe our technique of adding facet arthrodesis via the same corridor through which the pedicle screw is inserted with minimal addition of time or steps. Methods We demonstrate our technique of how we use navigation and tubular retractors to perform posterior facet arthrodesis during percutaneous pedicle screw placement. We illustrate this technique with a case of a patient with scoliosis, intraoperative photos, and an illustrative video. We also show an intraoperative computed tomography image to help visualize the arthrodesis surfaces. With this technique, we show how there are a few additional steps that are not very time consuming to add posterior arthrodesis. Results MIS facet fusion can be performed in a relatively straightforward manner during percutaneous pedicle fixation without significant addition of intraoperative time or steps. Conclusions It is possible to add posterior arthrodesis to percutaneous lumbar pedicle screw fusion with few added steps and minimal addition of time using navigation and MIS tubular retractors.

The continuous exploration of advanced electrode materials is of remarkable significance to revolutionize next-generation high-performance energy storage devices towards a green future. Benefiting from their electrochemically active sites and abundant redox centers, bimetallic selenides with desirable nanostructures recently have emerged as promising electrode alternatives for battery–supercapacitor hybrid (BSH) devices which demonstrate enormous potential in bridging the gap between electrochemical properties with high power densities (supercapacitors) and energy densities (batteries). Herein, employing the hydrothermal approach with solid Ni–Co spheres as precursors followed by the selenization process, selenide-rich bimetallic selenide spheres with a core–shell nanostructure were rationally designed and synthesized for use as the cathode electrode in superior BSH devices. The as-obtained (NiCo)9Se8/(NiCo)0.85Se (Ni–Co–Se) exhibits a high specific capacity of 164.44 mA h g−1 at a current density of 1 A g−1 with 85.72% capacity retention even after 5000 cycles at a current density of as high as 8 A g−1, suggesting its great promise in practical applications for BSH devices. By integrating activated carbon as the anode with the as-obtained bimetallic selenides as the cathode, an alkaline aqueous BSH device is fabricated and delivers a high energy density of 37.54 W h kg−1 at a high power density of 842.7 W kg−1. It is found that the excellent electrochemical performances can be ascribed to facile ion and electron transport pathways, high electrical conductivity and reliable structural robustness of the prepared selenides. Moreover, the synthetic strategy presented in this paper opens up an avenue to guide the synthesis of various anion doped bimetallic compounds towards high-performance energy conversion and storage devices.

The compounds in volatile flavor substances in duck meats of three different body parts (breast, leg, and wing) were extracted by headspace solid-phase micro-extraction and determined by gas chromatography-mass spectrometry. A total of 16 main volatile compounds including 4 hydrocarbons, 4 alcohols, 2 acids, 3 aldehydes, and 3 others (N-containing, S-containing) were identified in raw duck meats from three different body parts. The hydrocarbon compounds account for more than 50% of all volatile substances in all three body parts. And the percentage of hydrocarbon compounds in raw duck breast meat reaches 82.76%. A total of 81 volatile compounds including 15 hydrocarbons, 10 alcohols, 7 acids, 12 aldehydes, 4 esters, 19 S-containing and N-containing compounds, and 14 others were isolated and identified in 1 hr-marinated and cooked duck meats. A total of 101 kinds of volatile flavor compounds including 13 hydrocarbons, 14 alcohol, 7 acids, 8 aldehydes, 12 esters, 23 S-containing and N-containing compounds, and 24 others were detected in 3 hr-marinated duck meats of the three body parts. It was proved in this study that under the same conditions, the volatile compounds in duck legs are more than those in duck breasts and wings, and the types of volatile flavor substances increase significantly in duck meats after cooked. PRACTICAL APPLICATIONS: Prepared and cooked duck meat, especially wings and legs are popular food in China. The results suggest that Pickling makes duck meat more flavory while proper pickling time is less than 3 hr. Duck wings are better for marinating and cooking compared with duck breasts and legs. The acceptance study of duck meat from different body parts and the analysis of volatile flavor compounds are beneficial for optimizing utilization of whole parts of duck meat.

Advanced architecture and rational design of electrode materials for electrochemical sodium‐ion storage are well developed by researchers worldwide. MXene‐based materials are considered as one of the most potential electrode materials for sodium‐ion‐based devices, such as sodium‐ion batteries (SIBs), sodium–sulfur batteries (SSBs), and sodium‐ion capacitors (SICs), because of the excellent physicochemical characteristics of MXenes. Here, in this review, the recent research work and progress, both theoretical and experimental, on MXene‐based materials including pure MXenes and MXene‐based composites in application of SIBs, SSBs, and SICs are comprehensively summarized. The sodium storage mechanisms and the effective methods to enhance the electrochemical performance are also discussed. Finally, the current critical challenges and future research directions on the development of these MXene‐based materials for electrochemical sodium‐ion storage are presented., This review provides an in‐depth summary of the application of MXene‐based materials in the sodium‐ion storage, including the detailed sodium‐ion storage performances and mechanisms. Moreover, the relation between the structures and electrochemical performances and the corresponding effective strategies for further optimization are also discussed. In addition, the perspectives on dealing with current challenges are proposed.

Detrimental lithium polysulfide (LiPS) shuttle effects and sluggish electrochemical conversion kinetics in lithium-sulfur (Li-S) batteries severely hinder their practical application. Separator modification has been extensively investigated as an effective strategy to address above issues. Nevertheless, in the case of functional separators, how to effectively block the LiPSs from diffusion while enabling the rapid Li ion transport remains a challenge. Herein, by using an "oxidation-etching" method, MXene membranes are presented with controllable in-plane pores as interlayer to regulate Li ion transportation and LiPS immobilization. Porous MXene membranes with optimized pore density and size can simultaneously anchor LiPS and ensure fast Li ion diffusion. Consequently, even with pure sulfur cathode, the improved Li-S batteries deliver excellent rate performance up to 2 C with a reversible capacity of 677.6 mAh g-1 and long-term cyclability over 500 cycles at 1 C with a low capacity decay of 0.07% per cycle. This work sheds new insights into the design of high-performance interlayers with manipulated nanochannels and tailored surface chemistry to regulate LiPSs trapping and Li ion diffusion in Li-S batteries.

Self-assembled Ni(OH)2 nanosheet-decorated hierarchical flower-like MnCo2O4.5 nanoneedles were synthesized via a cost-effective and facile hydrothermal strategy, aiming to realize a high-capacity advanced electrode of a battery-supercapacitor hybrid (BSH) device. It is demonstrated that the as-synthesized hierarchical flower-like MnCo2O4.5@Ni(OH)2-nanosheet electrode exhibits a high specific capacity of 318 mAh g-1 at a current density of 3 A g-1 and still maintains a capacity of 263.5 mAh g-1 at a higher current density of 20 A g-1, with an extremely long cycle lifespan of 87.7% capacity retention after 5000 cycles. Moreover, using the unique core-shell structure as the cathode and hollow Fe2O3 nanoparticles/reduced graphene oxide as the anode, the BSH device delivers a high energy density of 56.53 Wh kg-1 when the power density reaches 1.9 kW kg-1, and there is an extraordinarily good cycling stability with the capacity retention rate of 90.4% after 3000 cycles. It is believed that the superior properties originate from desirable core-shell structures alleviating the impact of volume changes as well as the existence of two-dimensional Ni(OH)2 nanosheets with more active sites, thereby improving the cycle stability and achieving ultrahigh capacity. These results will provide more access to the rational material design of diverse nanostructures toward high-performance energy storage devices.

It is crucial to enhance anti-oxidation resistance of copper nanowires (Cu NWs) without degrading their transparent conductive characteristics. Here, reduced graphene oxide/copper nanowires (RGO/Cu NWs) with coating nanostructures were synthesized by a facile one-pot hydrothermal method. The copper nanowire was prepared by using copper (I) chloride as the precursor while the graphene oxide (GO) was reduced using the polyols as the reducing agent in order to obtain the coating structure, abandoning conventional tedious multi-step preparation processes. The microstructure and morphology of RGO/Cu NWs were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), selected-area electronic diffraction (SEAD) and X-ray photoelectron spectroscopy (XPS). The as-synthesized RGO/Cu NWs nanostructure is found to be almost coating structure of particle-free, high aspect ratio (L/D≈890) Cu NWs decorated with reduced graphene oxide (RGO), which accounts for the outstanding oxidation resistance. The stability tests show that the sheet resistance (RS) of the RGO/Cu NWs is almost unchanged over 20 days at room temperature or 5 h at 60 °C. What’s more, the sheet resistance of the RGO/Cu NWs with coating structure only increases to 2.48 times after being heated for 150 min at 100 °C, which can directly indicate that the RGO/Cu NWs nanostructure has excellent anti-oxidation resistance and temporal stability. Also, the as-prepared RGO/Cu NWs transparent electrode has both low sheet resistance of 58.36 Ω/sq and high optical transmittance (87.12% @550 nm). The composite materials provide a better strategy to resolve the problem of being easily oxidized for Cu NWs and promote their wide practical applications.

The design of flexible electrodes with high areal capacitance is the key for the application of flexible asymmetric supercapacitors (ASCs) in portable and wearable electronics. In this study, Ti3C2Tx MXene coupled with the Fe2O3/CC flexible negative electrode, with good conductivity, high areal capacitance, and excellent flexibility, was fabricated by a simple dipping method, in which the as-grown Fe2O3 nanorod arrays on carbon cloth were dipped into the few-layered MXene nanosheet solution repeatedly to make the Fe2O3/CC fibers wrapped with MXene completely. The MXene@Fe2O3/CC electrode presents a remarkable areal capacitance of up to 725 mF cm−2 at a current density of 1 mA cm−2 which was contributed by both MXene and Fe2O3 nanorods. As to the MXene layer, it not only offers capacitance for the flexible electrode, but also provides fast and efficient ion/electron transport pathways for Fe2O3 to effectively improve electronic conductivity. Besides, the as-constructed ASC devices consisting of MXene@Fe2O3 and MnO2 electrodes achieve a high energy density of 1.61 mW h cm−3 at a power density of 22.55 mW cm−3 along with good stability. The work provides a simple effective strategy to load active materials on carbon fibres and to construct hierarchical coating-structured electrodes for high-performance flexible ASC application.

Stroke is one of the leading causes of death and disability globally, while intravenous thrombolysis with recombinant tissue plasminogen activator remains the only Food and Drug Administration (FDA)-approved therapy for ischemic stroke. The attempts to develop new treatments for acute ischemic stroke meet costly and spectacularly disappointing results, which requires both long time and high costs, whereas repurposing of safe existing drugs to new indications provides a cost-effective and not time-consuming alternative. Vascular protection is a promising strategy for improving stroke outcome, as vascular function is critical to both cardiovascular diseases (CVD) and ischemic cerebrovascular disease (ICD). Vascular function related biological processes and pathways maybe the critical associations between CVD and ICD. In this study, a multi-database, in silico target identification, gene function enrichment, and network pharmacology analysis integration approach was proposed and applied to investigate the FDA-approved CVD drugs repurposing for ICD. A list of 119 candidate drugs can be obtained for further investigation of their potential in ICD treatment. As a pleiotropic drug with multi-target, carvedilol was set an example to investigate its promising potential for ICD therapy. Our results indicated that the mode of action of carvedilol for ICD treatment may tightly associated with vascular function regulation and the mechanism is multi-target and multi-signaling pathway related. The disease-disease association network-assisted prediction needs further investigations. In summary, the proposed methods herein may provide a promising alternative to inferring novel disease indications for known drugs.

Rational materials design for the synthesis of desirable hollow micro- and nanostructures has recently revealed the remarkable potential for high-performance energy storage and conversion devices. Owing to their unique "core-void-shell" structural configurations, yolk-shell-structured electrode materials can achieve intimate contact with the electrolyte and alleviate the volume expansion issue during electrochemical cycling, which is therefore poised to further boost the electrochemical properties of hybrid supercapacitors. Herein, a facile self-templated strategy, consisting of a hydrothermal step and a high-temperature sulfurization process, has been developed for the construction of yolk-shell (NiCo)9S8 spheres in situ coated by graphite carbon ((NiCo)9S8/GC) due to the non-equilibrium thermal treatment of alkali metal alkoxides. The as-synthesized yolk-shelled sphere exhibits a high specific capacitance of 1434.4 F g-1 (179.3 mA h g-1) at a current density of 1 A g-1, and good rate capability and cycling stability with 83.1% capacitance retention at 8 A g-1 over 5000 cycles. To further demonstrate its practical application, a hybrid supercapacitor device was assembled using (NiCo)9S8/GC as the battery-type positive electrode and activated carbon (AC) as the capacitive-type electrode. The as-fabricated device can reach a wide voltage window of up to 1.6 V, deliver a high energy density of 55.6 W h kg-1 at a power density of 800.3 W kg-1 and maintain 90.2% of specific capacitance after 3000 cycles.

Atomic force microscopy (AFM) is a powerful instrument that has the ability to characterize sample topography on nanoscale resolution. AFM is widely used in different fields, such as nanotechnology, semiconductor, Microelectromechanical Systems (MEMS), bioscience. In the case of obtaining 3D topography of a large range sample, we need to know the relative position of the AFM probe to the sample. The scanning range of an AFM generally is much smaller than the sample size. Therefore, it is hard to localize the AFM tip position without other auxiliary microscopes such as optical microscope. Moreover, the AFM scanned images on a MEMS sample typically involve only simple geometries with sparse features which usually leads to the difficulty of localization. Besides, the system uncertainties including piezoelectric scanner hysteresis, thermal drift, and coarse dual stage would affect positioning accuracy. In this paper, we propose an AFM tip localization method using particle filter referring to macro robot Simultaneous localization and mapping (SLAM). We take the AFM scanned image as the unique sensor and the sample layout as the map. The sensor model of the particle filter is based on a feature extraction algorithm. To verify the efficacy of the proposed methods, both simulations and experiments are conducted, and the proposed tip localization method is highly promising.

Transition metal oxides have recently been demonstrated as highly attractive anodes for high-capacity lithium ion batteries, whose electrochemical properties could be further improved through rational architecture design and incorporating reliable conductive network. Herein, mesoporous γ-Fe

Background Patients with metastatic lung cancer have a series of symptoms and many severe treatment-related side effects. However, little evidence is in support of benefits in performing exercise during their hospitalization. The purpose of this study was to understand exercise experiences inpatients with metastatic lung cancer. Methods A qualitative approach with face-to-face in-depth interview was conducted at an inpatient ward of a medical center in central Taiwan, on 24 recruited participants with metastatic lung cancer. The interview transcripts went through a narrative analysis by a group of qualitative research experts to extract and validate the main themes. Results Three primary themes were identified: (a) modifying exercise to maximize physical functions, (b) living with symptoms and frustration but continuing exercise, and (c) doing exercise to sustain hopes, inner power, and life. Two secondary findings were: (a) most participants adopted walking as their main form of exercise because of its flexibility, and (b)participants, according to the severity of their symptoms, adjusted their exercise towards shorter time durations and shorter distances, slower speeds, and higher frequencies. Conclusions Participants with metastatic lung cancer adjusted their exercise behaviors to balance disease and treatment-induced deteriorations and to boost themselves to fight cancer and sustain survival. Individualized exercise schemes should be adopted in clinical practice to enhance their physical functions and life meaning. Such a home-based rehabilitation program in exercise was acceptable to most participants with metastatic lung cancer, including improvements in physical fitness, motivation, and the ability to manage symptoms.

The triboelectric nanogenerator (TENG), based on triboelectrification and electrostatic induction, has been proven to be an ideal power supply device which converts all kinds of mechanical energy into electrical energy. However, high cost of fabrication and modification prevents wide application. In this work, we demonstrated a simple, cost-effective but efficient method, in which the friction pair materials, i.e., copper electrode and polydimethylsiloxane (PDMS), were both patterned by using sandpaper templates. The copper electrode and PDMS were patterned with sandpaper-like morphology and sandpaper-complementary-like morphology, respectively. Compared with TENG devices with nonpatterned or single-sided patterned friction layer, TENG devices with two-sided patterned friction layers have better output properties when the sandpaper templates used for the PDMS and copper electrode have the same large grit sizes (above 2000) because of closer contact and more sufficient friction. When the sandpaper templates used for the PDMS and copper electrode have the same grit size of 10 000, the maximum output short-circuit current density, open-circuit voltage, transfer charge quantity, and power density of as-prepared TENG devices are 3.89 mA/m2, 200 V, 76 nC, and 4.36 W/m2, respectively. Overall, patterning microstructure morphology and corresponding complementary morphology on the respective two sides of friction pair shows efficient improvement for the performance of the TENG device, providing a good guidance for its modification.