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In recent years, the in situ resource utilization of CO2 in the Martian atmosphere by low-temperature plasma technology has garnered significant attention. However, numerical simulation is extremely time-consuming for modeling the complex CO2 plasma, involving tens of species and hundreds of reactions, especially under Martian pressure. In this study, a deep neural network (DNN) with multiple hidden layers is introduced to investigate the CO2 conversion in radio-frequency (RF) discharges at a given power density under Martian pressure in almost real time. After training on the dataset obtained from the fluid model or experimental measurements, the DNN shows the ability to accurately and efficiently predict the various discharge characteristics and plasma chemistry of RF CO2 discharge even in seconds. Compared with conventional fluid models, the computational efficiency of the DNN is improved by nearly 106 times; thus, a real-time calculation of RF CO2 discharge can almost be achieved. The DNN can provide an enormous amount of data to enhance the simulation results due to the very high computational efficiency. The numerical data also suggest that the CO2 conversion increases with driving frequency at a fixed power density. This study shows the ability of the DNN-based approach to investigate CO2 conversion in RF discharges for various applications, providing a promising tool for the modeling of complex non-thermal plasmas.

Abstract Recently, the applications of cold atmospheric plasma (CAP) in liquid treatment have attracted increasing attention owing to its excellent medical efficacy. It has been proved that CAP can effectively enhance the biological activity of vegetable oils due to the generation of reactive species. Optimising the reactor parameter is an important approach to regulate reactive species in plasma‐activated oil to obtain better biological effects. In this study, a self‐made jet array driven by a pulsed power supply was used to generate large‐area plasma to irradiate perilla seed oil (PSO), with the formation of plasma‐activated perilla seed oil (PAPSO). By means of laser‐induced fluorescence and chemical titration, the relative density of hydroxyl radical radical in plasma jet, as well as the activity of PAPSO were measured under different discharge parameters, and realised the control of the activity of PAPSO. In vitro experiments showed that PAPSO significantly enhanced its ability to inhibit cancer cells proliferation and induce apoptosis after plasma treatment, which provides a reference for cancer treatment. This study is helpful to further understand the influence of plasma dose effect on the activity of media and provide guidance for related plasma medical applications.

Abstract The knowledge of osteoarthritis (OA) has nowadays been extended from a focalized cartilage disorder to a multifactorial disease. Although recent investigations have reported that infrapatellar fat pad (IPFP) can trigger inflammation in the knee joint, the mechanisms behind the role of IPFP on knee OA progression remain to be defined. Here, dysregulated osteopontin (OPN) and integrin β3 signaling are found in the OA specimens of both human and mice. It is further demonstrated that IPFP‐derived OPN participates in OA progression, including activated matrix metallopeptidase 9 in chondrocyte hypertrophy and integrin β3 in IPFP fibrosis. Motivated by these findings, an injectable nanogel is fabricated to provide sustained release of siRNA Cd61 (RGD−Nanogel/siRNA Cd61) that targets integrins. The RGD−Nanogel possesses excellent biocompatibility and desired targeting abilities both in vitro and in vivo. Local injection of RGD−Nanogel/siRNA Cd61 robustly alleviates the cartilage degeneration, suppresses the advancement of tidemark, and reduces the subchondral trabecular bone mass in OA mice. Taken together, this study provides an avenue for developing RGD−Nanogel/siRNA Cd61 therapy to mitigate OA progression via blocking OPN‐integrin β3 signaling in IPFP.

Plasma medicine, or the biomedical application of cold atmospheric plasma (CAP), is an expanding field within plasma research. CAP has demonstrated remarkable versatility in diverse biological applications, including cancer treatment, wound healing, microorganism inactivation, and skin disease therapy. However, the precise mechanisms underlying the effects of CAP remain incompletely understood. The therapeutic effects of CAP are largely attributed to the generation of reactive oxygen and nitrogen species (RONS), which play a crucial role in the biological responses induced by CAP. Specifically, RONS produced during CAP treatment have the ability to chemically modify cell membranes and membrane proteins, causing nitro-oxidative stress, thereby leading to changes in membrane permeability and disruption of cellular processes. To gain atomic-level insights into these interactions, non-reactive molecular dynamics (MD) simulations have emerged as a valuable tool. These simulations facilitate the examination of larger-scale system dynamics, including protein-protein and protein-membrane interactions. In this comprehensive review, we focus on the applications of non-reactive MD simulations in studying the effects of CAP on cellular components and interactions at the atomic level, providing a detailed overview of the potential of CAP in medicine. We also review the results of other MD studies that are not related to plasma medicine but explore the effects of nitro-oxidative stress on cellular components and are therefore important for a broader understanding of the underlying processes.

The abuse of tetracycline antibiotics (TCs) has caused serious environmental pollution and risks to public health. Degradation of TCs by cold atmospheric plasmas (CAPs) is a high efficiency, low energy consumption and environmentally friendly method. In this study, a reactive molecular dynamics (MD) simulation is applied to study the interactions of reactive oxygen species (ROS) produced in CAPs and TCs (including tetracycline (TC), oxytetracycline (OTC), chlortetracycline (CTC) and demeclocycline (DMC)). As revealed by the simulation data at the atomic level, the main reaction sites on TCs are the C2 acylamino, the C4 dimethylamine, the C6 methyl group, the C8 site on the benzene ring and the C12a tertiary alcohol. The interaction between ROS and TCs is usually initiated by H-abstraction, followed by the breaking and formation of the crucial chemical bonds, such as the breaking of C-C bonds, C-N bonds and C-O bonds and the formation of C=C bonds and C=O bonds. Due to the different structures of TCs, when the ROS impact OTC, CTC and DMC, some specific reactions are observed, including carbonylation at the C5 site, dechlorination at the C7 site and carbonylation at the C6 site, respectively. Some degradation products obtained from the simulation data have been observed in the experimental measurements. In addition, the dose effects of CAP on TCs by adjusting the number of ROS in the simulation box are also investigated and are consistent with experimental observation. This study explains in detail the interaction mechanisms of degradation of TCs treated by CAPs with the final products after degradation, provides theoretical support for the experimental observation, then suggests optimization to further improve the efficiency of degradation of TCs by CAPs in applications.

Abstract Strain modulation is crucial for heteroepitaxy such as GaN on foreign substrates. Here, the epitaxy of strain-relaxed GaN films on graphene/SiC substrates by metal-organic chemical vapor deposition is demonstrated. Graphene was directly prepared on SiC substrates by thermal decomposition. Its pre-treatment with nitrogen-plasma can introduce C–N dangling bonds, which provides nucleation sites for subsequent epitaxial growth. The scanning transmission electron microscopy measurements confirm that part of graphene surface was etched by nitrogen-plasma. We study the growth behavior on different areas of graphene surface after pre-treatment, and propose a growth model to explain the epitaxial growth mechanism of GaN films on graphene. Significantly, graphene is found to be effective to reduce the biaxial stress in GaN films and the strain relaxation improves indium-atom incorporation in InGaN/GaN multiple quantum wells (MQWs) active region, which results in the obvious red-shift of light-emitting wavelength of InGaN/GaN MQWs. This work opens up a new way for the fabrication of GaN-based long wavelength light-emitting diodes.

Background/objective: The tibial cortex transverse transport (TTT) surgery has been reported for the treatment of severe diabetic foot ulcers with satisfactory clinical outcomes. TTT surgery can effectively regenerate the microvascular network in the lower limbs of these patients to promote ulcer healing and increase the chance of limb salvage. Methods: In this report, the authors provide a technical guide to perform minimally invasive TTT surgery through the use of a specially designed external fixation frame and tibial corticotomy guide plate. Results: This minimally invasive technique utilizes smaller skin incisions and preserves the local blood supply. Conclusion: Our minimally invasive TTT surgery technique is a simple procedure that significantly increased the efficacy and reduced the complications of TTT surgery. The Translational potential of this article: This report provides a step-by-step guide on how to perform minimally invasive TTT surgery. The use of specially designed external fixator and corticotomy guide plate are the key factors for a reproducible and successful TTT surgery. This report will serve as a reference guide for surgeons to perform TTT surgery.

Objective: The objective of this study was to assess the efficacy and safety of denosumab therapy in osteoporotic postmenopausal women who were previously treated with bisphosphonates. Methods: Meta-analyses of four available randomised controlled trials that compared osteoporotic patients who switched to denosumab from bisphosphonates (n ​= ​1416) and those who continued bisphosphonates therapy (n ​= ​1411) were included. Results: The increase in bone mineral density (BMD) of both the spine and hip was significantly higher in patients who shifted to denosumab than in those who continued bisphosphonates. Despite the incidence of adverse events (AEs) and fractures being comparable, treatment withdrawal owing to AEs was significantly less frequent in the denosumab group. Conclusion: The outcomes and treatment compliance were improved in postmenopausal osteoporotic women who shifted to denosumab from bisphosphonates. The translational potential of this article: The replacement of bisphosphonates with denosumab may lead to better therapeutic efficacy and fewer adherence barriers ​than those with continued usage of bisphosphonates, which in the future may guide the choice of drug therapy in clinics.

Nitrogen-polar (N-polar) III-nitride has natural advantages in the fabrication of electronic devices. In this work, unintentionally doped N-polar GaN films were grown on sapphire substrates by metalorganic chemical vapor deposition. By optimizing the growth parameters including growth temperature, pressure, and V/III ratio, N-polar GaN with a relatively high sheet resistivity of 3.6 × 105 Ω/sq was achieved. The secondary ion mass spectroscopy and x-ray diffraction measurement results demonstrate that the increased carbon impurity concentration is primarily responsible for the high resistivity. Moreover, N-polar GaN/Al0.25Ga0.75N heterojunctions were deposited on the high-resistivity N-polar GaN template. An extremely high-density two-dimensional electron gas of up to 1.12 × 1013 cm−2 was realized at the interface between the Al0.25Ga0.75N and the GaN. It is reasonably believed that the experimental results obtained here are beneficial for the development of high-performance N-polar GaN-based electronic devices.

In this article, we reported on a Ga2O3-based Schottky barrier diode and heterojunction diode from MOCVD. The Si-doped n-type Ga2O3 drift layer, grown by MOCVD, exhibited high crystal quality, flat surfaces, and uniform doping. The distribution of unintentional impurities in the films was studied. Then nickel Schottky barrier diode and p-NiO/n-Ga2O3 heterojunction diode were fabricated and measured. Without any electric field management structure, the Schottky barrier diode and heterojunction diode have specific resistances of 3.0 mΩ·cm2 and 6.2 mΩ·cm2, breakdown voltages of 380 V and 740 V, thus yielding power figures of merit of 48 MW·cm−2 and 88 MW·cm−2, respectively. Besides, both devices exhibit a current on/off ratio of more than 1010. This shows the prospect of MOCVD in power device manufacture.

In recent years, the in situ resource utilization of CO2 on Mars for oxygen and carbon monoxide production has attracted increasing attention. Dielectric barrier discharges (DBDs) have great potential for large-scale industrial application of CO2 decomposition, and the nonlinear behaviors of DBDs are directly related to the discharge stability. In this paper, a fluid model is built to investigate the influence of gap width on temporal nonlinear behaviors in CO2 DBDs driven by tailored voltages under Martian conditions (the pressure and temperature are 4.5 Torr and 210 K, respectively). The simulation results show that, with the increase in the gap width, the discharge evolves from period-one state into period-two state, then changes into chaos, and finally undergoes an inverse period-doubling bifurcation from reverse period-two discharge to period-one discharge. After the CO2 discharge is extinguished, the electron density drops rapidly, and the dominant charged particles in the discharge region are heavy CO3− and CO2+ ions. As the gap width increases, the heavy ions produced by the previous discharge cannot be completely dissipated and stay in the sheath region, which makes the subsequent discharge easy to be ignited and reduces the breakdown voltage, leading to the evolution from period-one discharge to period-two discharge. When the gap width is increased to 5 mm, a lot of charged particles stay in the discharge gap, and these charged particles, especially electrons, are driven to the electrodes by the applied voltage, forming a reverse electric field, which inhibits the development of positive discharge and facilitates the formation of negative discharge. Then, as the gap width continues to increase, the density and spatial distribution of residual ions in the sheath region at the beginning of the negative discharge for two consecutive voltage periods are gradually equal, resulting in the discharge evolution from reverse period-two state to reverse period-one state. This study could deepen the understanding of the underpinning physics of nonlinear behaviors, and provide a groundwork for actively regulating the evolution of nonlinear behaviors.

Abstract A 3D ITO nanowire network with high quality by using polystyrene as an assisted material has been prepared, demonstrating superior optoelectronic performances with a sheet resistance of 193 Ω/sq at 96% transmission. Both remarkable flexibility tested under bending stress and excellent adhesion applied on special terrain substrate have been achieved. This method has led to a full coverage of micro-holes at a depth of 18 µm and a bottom spacing of only 1 µm, as well as a perfect gap-free coverage for micro-tubes and pyramid array. It has been proved that this 3D ITO nanowire network can be used as a transparent conductive layer for optoelectronic devices with any topography surface. Through the application on the micro-holes, -tubes and -pyramid array, some new characteristics of the 3D ITO nanowires in solar cells, sensors, micro-lasers and flexible LEDs have been found. Such 3D ITO nanowire networks could be fabricated directly on micro-irregular substrates, which will greatly promote the application of the heterotypic devices.

Leaf area index (LAI) is one of the important variables for crop growth monitoring and yield estimating. In this article, the potato LAI was retrieved by several vegetation indices (VIs) and spectral parameters of the continuum removal method (SPCRM) to provide accurate estimates. A comparison of the two methods of retrieving precision was completed. The data source for computing VIs and SPCRM was hyperspectral reflectance data for the life cycle, derived from two potato cultivars, Favorite (early maturing variety) and Yanshu 4 (late maturing variety), through field experiments. Sensitive bands were identified to indicate seven VIs by correlation analysis. Additionally, seven SPCRM were computed. Based on these methods, the potato LAI was retrieved and tested. Meanwhile, a comparison of the retrieving precision was implemented. The results showed that compared with the filtered spectral reflectance and VIs, the correlation between the potato LAI and the continuum removal spectral reflectance and its retrieved SPCRM were higher. The determination coefficients (R2) of the retrieving models of four parameters, the total area (S), the left area (Sl), the right area (Sr) and the depth area ratio (W), derived from the continuum removal method were all above 0.801, and their fitting coefficients (r) were all above 0.868, with the mean relative errors (MRE) all

Abstract Epitaxial growth of III‐nitrides on 2D materials enables the realization of flexible optoelectronic devices for next‐generation wearable applications. Unfortunately, it is difficult to obtain high‐quality III‐nitride epilayers on 2D materials such as hexagonal BN (h‐BN) due to different atom hybridizations. Here, the epitaxy of single‐crystalline GaN films on the chemically activated h‐BN/Al2O3 substrates is reported, paying attention to interface atomic configuration. It is found that chemical‐activated h‐BN provides BON and NO bonds, where the latter ones act as effective artificial dangling bonds for following GaN nucleation, leading to Ga‐polar GaN films with a flat surface. The h‐BN is also found to be effective in modifying the compressive strain in GaN film and thus improves indium incorporation during the growth of InGaN quantum wells, resulting in the achievement of pure green light‐emitting diodes. This work provides an effective way for III‐nitrides epitaxy on h‐BN and a possible route to overcome the epitaxial bottleneck of high indium content III‐nitride light‐emitting devices.

Dielectric barrier discharge (DBD) is an effective method for treating volatile organic compounds (VOCs). In the presence of a photocatalyst, photocatalytic technology can be used to generate a variety of reactive oxygen species (ROS). Numerous experiments have demonstrated that DBD–photocatalyst synergism is superior to the use of either approach individually. In this study, the degradation mechanism of VOCs under the DBD–photocatalyst system was investigated via the ReaxFF reaction molecular dynamics method. Acetaldehyde, toluene, 1,2,4-trimethylbenzene, cresol, and phenol were selected as representative VOCs and · O, · OH, HO2, and H2O2 were chosen as representative ROS to construct the DBD and DBD–photocatalyst reaction systems. A concentration control group and a component control group were established. Comparison of the various ROS revealed that · O and · OH possess higher activities and are more conducive to cracking VOC molecules. Among the various VOCs, the reaction rate was faster for highly reductive reactants. The carbon conversion rate was only dependent on the molecular complexity and was higher for simpler structures. To simulate the DBD–photocatalyst synergistic conditions, we established concentration control simulation systems. When · OH is used as the ROS, a large number of oxidative adsorption and hydrogen abstraction processes can occur. Increasing the · OH concentration promotes the VOC removal reactions to afford complete cracking of the VOCs into the small-molecule product CO2.

Heavily Sn-doped In2O3nano-pyramids with a Sn percentage of 19.97% by weight have been prepared by sputtering technique. The nano-pyramids with smooth facets and a sharp tip have been achieved by deposition on Sn-metal particles, leading to a diameter of ∼100nm. The gas sensors realized from these pyramids are highly sensitive to ethanol gas, and the sensitivity is about 133.99 against 200ppm ethanol at 250°C. Good sensitivity characteristics have been obtained even at a low temperature of down to 50°C. The high response and low working temperature demonstrate the potential application of heavily Sn-doped In2O3 nano-pyramids for fabricating gas sensors.

Background: Metastasis is a leading cause of mortality for osteosarcoma (OS) patients, and its molecular pathological mechanisms remain to be elucidated. Previous studies have suggested a significant role of microRNAs (miRNAs) in the control of cancel cell migration and invasion. Methods: Real-time PCR was used to screen the differentially expressed miRNAs between OS with or without metastasis, and miR-145 underexpression was observed in metastatic OS. Luciferase assay was performed to validate the target gene. Results: Further, we identified three genes, MMP16, ADAM17 and metadherin, as possible targets of miR-145. We identified MMP16 as a target gene of miR-145 and ruled out ADAM17 and metadherin as targets in OS using a dual luciferase reporter system. Subsequently, we determined and compared the expression level of MMP16 in human OS samples and showed that the mRNA and protein levels of MMP16 were significantly up-regulated in primary OS with metastasis compared with those without metastasis. We also altered miR-145 expression by transfecting OS cells with miR-145 mimics or inhibitors. MMP16 expression was similarly downregulated in the cells transfected with miR-145 mimics or MMP16-specific siRNA, and the invasive and migratory capability of those cells was significantly suppressed compared with negative controls. MMP16 expression was consistently significantly upregulated in the cells transfected with miR-145 inhibitors, and the invasive and migratory capability of those cells was significantly promoted compared with negative controls. Conclcusion: Our results suggest that miR-145 functions as a tumor metastasis suppressor gene by down-regulating MMP16 and may be a potential target in osteosarcoma treatment.

n-ZnO/p-GaN heterojunction light-emitting diodes with a p-GaN/Al0.1Ga0.9N/n+-GaN polarization-induced tunneling junction (PITJ) were fabricated by metal-organic chemical vapor deposition. An intense and sharp ultraviolet emission centered at ∼396 nm was observed under forward bias. Compared with the n-ZnO/p-GaN reference diode without PITJ, the light intensity of the proposed diode is increased by ∼1.4-folds due to the improved current spreading. More importantly, the studied diode operates continuously for eight hours with the decay of only ∼3.5% under 20 mA, suggesting a remarkable operating stability. The results demonstrate the feasibility of using PITJ as hole injection layer for high-performance ZnO-based light-emitting devices.

Yellow luminescence (YL) of unintentionally doped GaN (u-GaN) peaking at about 2.2 eV has been investigated for decades, but its origin still remains controversial. In this study, ten u-GaN samples grown via metalorganic chemical vapor deposition (MOCVD) are investigated. It is observed from the room temperature (RT) photoluminescence (PL) measurements that the YL band is enhanced in the PL spectra of those samples if their MOCVD growth is carried out with a decrease of pressure, temperature, or flow rate of NH3. Furthermore, a strong dependence of YL band intensity on the carbon concentration is found by secondary ion mass spectroscopy (SIMS) measurements, demonstrating that the increased carbon-related defects in these samples are responsible for the enhancement of the YL band.

Polyvinylidene fluoride (PVDF) has broad application prospects in the field of dielectric capacitors. However, the low dielectric constant of the polymer greatly limits the improvement of its energy storage density. In this paper, a highly conductive two-dimensional transition metal carbide (MXene) is utilized to modify PVDF by doping to prepare PVDF/MXene composite dielectrics, and a PVDF/MXene model is established based on molecular dynamics simulations to investigate the microscopic mechanism of improvement in the dielectric properties of the PVDF matrix upon doping. Finally, the effect of the MXene on the thermal conductivity and the mechanical and insulating properties of PVDF was investigated. The experimental results show that the relative dielectric constant of the PVDF/MXene-1.0 wt% system at 100 Hz reached 14.54, which is 55.96% higher than that of pure PVDF, and this doping amount or lower can reduce the dielectric loss of PVDF. In addition, MXene doping improved the mechanical and thermal properties of the composite material to a certain degree. When the doping amount of MXene was lower than 1.0 wt%, the electric breakdown strength of the composite system was maintained above 245 MV/m, which is sufficient to achieve good insulation strength under most conditions. Highlights • The low dielectric constant of polymers limits the improvement of their energy storage density. • The doping of polymers with small amounts of conductive fillers can effectively increase the dielectric constant of the polymer matrix. • A two-dimensional nanomaterial MXene is used to improve the dielectric properties of PVDF matrix and the micromechanisms are analyzed by molecular dynamics simulations. • The key properties of PVDF/MXene, such as the mechanical properties, thermal conductivity and insulation, are characterized. [ABSTRACT FROM AUTHOR]