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Deviant peer affiliation (DPA) and moral disengagement (MD) play a vital role in adolescents’ cyberbullying perpetration (CP). However, moderating mechanisms underlying this association remain largely unknown. Based on the Social-ecological conceptual framework of cyberbullying (SECF-C), we tested a moderated mediating model to examine whether MD mediated the relationships between DPA and CP and whether these mediating processes were moderated by neuroticism and gender. A sample of 777 adolescents (aged from 11 to 16 years) participated in our survey. The results revealed that MD partially mediated the connections between DPA and CP. Also, neuroticism moderated the relationship between DPA and CP in adolescent boys. Finally, neuroticism and gender moderated the relationship between MD and CP, revealing the conditional indirect effects of DPA on CP via MD. The indirect impact was more pronounced for boys and high neuroticism. These mechanisms have potential implications for developing tailored interventions and preventive strategies. [ABSTRACT FROM AUTHOR]

To analyze the influence of wind load on the axial cable force in the flexible cable supported photovoltaic (PV), wind loads on PV modules at different wind directions, inclinations and spacing ratios are obtained through rigid model wind tunnel test. Three models are established and the axial cable forces under different conditions are calculated. The results show that the wind load on PV module varies with the position, and the wind load in the middle range is stronger than in others. The axial force on the cable is larger when the wind load is exerted as a concentrated load. The variation of the forces on support system with different inclination is also inconsistent with the layout (spacing ratio). Based on the analysis results, the present results suggest using a small spacing ratio and a large span, and the spacing ratio should be within 0.1. The wind load on the photovoltaic panel can be treated as a concentrated force to calculate the cable force. Meanwhile, the axial cable force caused by wind load can be estimated by the proposed ratio of wind load to axial cable force. [ABSTRACT FROM AUTHOR]

ScAlN/GaN dielectric superjunction high-electron-mobility transistors (HEMTs) with high-k passivation layer Bi1.5Zn1.0Nb1.5O7 (BZN) are demonstrated for enhancement of breakdown voltage. The BZN thin film deposited by RF magnetron sputtering has a dielectric constant of 192 after postdeposition annealing at 400 °C for 10 min. The HEMT with Lg = 200 nm and Lsd = 2.0 μ m has a maximum current density of 1.98 A/mm, a maximum transconductance of 0.52 S/mm, and a threshold voltage of Vth = −3 V. With the use of SiN/BZN/SiN sandwiched passivation layer, the average value of breakdown voltage is improved from 68.9 to 121.5 V, due to the reduction of the peak electrical field between the gate and the drain. The device has a cutoff frequency (ƒT) and maximum oscillation frequency (ƒmax) of 59 and 69 GHz, respectively. Overall, the devices exhibit a significantly higher breakdown voltage with essentially the same ƒT and ƒmax values. Pulse measurements suggest that SiN/BZN/SiN has a similar passivation effect in comparison with devices passivated by a SiN-only layer. This work demonstrates that high current and high breakdown voltage can be achieved simultaneously on semiconductor heterostructures with a high sheet charge density by integration of high-k dielectrics. [ABSTRACT FROM AUTHOR]

We report an electron transport study of an La-doped perovskite oxide BaSnO3 thin film grown by molecular beam epitaxy on (110) DyScO3 as a function of electron concentration, by etching the film step-by-step with nanometer precision. Inductively coupled plasma-reactive ion etching with BCl3/Ar plasma is used for etching depth control. The local doping and electron density are experimentally determined after each etching step. The results show that the electron mobility is dominated by threading dislocations if the electron concentration is below 7.8 × 1019 cm−3, while ionized impurities and phonon scattering become more dominant at electron concentrations greater than 1.2 × 1020 cm−3. The charging state of thread dislocations is estimated to be 6.2. Furthermore, using the etch process to control the electron concentration and channel thickness, a gate-recessed ferroelectric field effect transistor is fabricated with 10 nm HfO2 as a gate dielectric. The device exhibits a saturation current of 29.9 mA/mm with a current on/off ratio of Ion/Ioff = 8.3 × 108 and a ferroelectric polarization charge density of 1.9 × 1013 cm−2. Under the forward gate bias sweep, the device operates in the enhancement mode with a threshold voltage of 3 V. Under the reverse gate sweeping bias, the device operates in the depletion mode with a threshold voltage of –1.5 V. [ABSTRACT FROM AUTHOR]

A negative‐capacitance high electron mobility transistor (NC‐HEMT) with low hysteresis in the subthreshold region is demonstrated in the wide bandgap AlGaN/GaN material system using sputtered BaTiO3 as a "weak" ferroelectric gate in conjunction with a conventional SiNx dielectric. An enhancement in the capacitance for BaTiO3/SiNx gate stacks is observed in comparison to control structures with SiNx gate dielectrics directly indicating the negative capacitance contribution of the ferroelectric BaTiO3 layer. A significant reduction in the minimum subthreshold slope for the NC‐HEMTs is obtained in contrast to standard metal‐insulator‐semiconductor HEMTs with SiNx gate dielectrics—97.1 mV dec−1 versus 145.6 mV dec−1—with almost no hysteresis in the ID–VG transfer curves. These results are promising for the integration of ferroelectric perovskite oxides with III‐Nitride devices toward NC‐field‐effect transistor switches with reduced power consumption. [ABSTRACT FROM AUTHOR]

High-current molecular beam epitaxial perovskite oxide semiconductor BaTiO3/BaSnO3 heterostructure field effect transistors on SrTiO3 substrates were developed. Record high current density of $\text{I}_{{\mathrm{max}}} =406.7$ mA/mm, maximum transconductance $\text{g}_{{{\text {m}}}} =72.3$ mS/mm were achieved in a field effect transistor with gate length $\text{L}_{{{\text {g}}}} = 0.64\,\,\mu \text{m}$ , and source-drain spacing $\text{L}_{{{\text {sd}}}} = 3.5\,\,\mu \text{m}$. The device has a low threshold voltage of $\text{V}_{{{\text {th}}}}= - 4.5$ V and the capability to modulate $5.7\times 10^{{{{13}}}}$ cm $^{{-{2}}}$ electron density in the BaSnO3 channel. The high channel current and gate modulation efficiency are attributed to the high mobility and charge density in the BaSnO3 channel and the utilization of high-k BaTiO3 ($\varepsilon $ is in the range of 425 and 387 as the electric field increases from 46 to 85 kV/cm) layer as the gate dielectric for charge modulation. Though the device suffers from low current ON/OFF ratio and a large subthreshold swing due to the gate leakage resulted from threading dislocations, this work demonstrates the great potential of perovskite semiconductors for electronic device applications. [ABSTRACT FROM AUTHOR]

In this Letter, we demonstrate a Pt/BaTiO3/Al0.58Ga0.42N lateral heterojunction diode with enhanced breakdown characteristics. By using BaTiO3, a high-k material, as a dielectric material between the anode and semiconductor, the peak electric field at the anode edge near the cathode was significantly reduced and an average breakdown field exceeding 8 MV/cm was achieved for devices with an anode to cathode spacing of <0.2 μm. In contrast, Pt/Al0.58Ga0.42N control Schottky diodes displayed an average breakdown field of ∼4 MV/cm for devices with similar dimensions. The use of a high-k dielectric can more effectively utilize the high breakdown fields in ultra-wide bandgap materials by proper management of the electric field. This demonstration thus provides a framework to realize ultra-scaled lateral devices with improved breakdown characteristics. [ABSTRACT FROM AUTHOR]

The etching of epitaxially grown perovskite oxide BaSnO3 (BSO) and BaTiO3 (BTO) thin films is studied using Cl-based (BCl3/Ar) and F-based (CF4/Ar) plasma chemistries in an inductively coupled plasma reactive ion etching (ICP-RIE) system for the development of field effect transistors (FETs). It is found that the BCl3/Ar process has a time-independent and a higher etch rate and creates a smooth etched surface, while the etch rate of BSO and BTO in CF4/Ar plasma decreases with the etching time duration. For the BCl3/Ar etching process, the etch rate increases with both ion density and ion energy, suggesting the combination of chemical plasma etching and physical ion sputtering mechanisms. Using the Cl-based etching process, BaSnO3 and BaTiO3 heterojunction FETs are developed. The devices with a gate length of 1.5 μm have a saturation current density of 287.6 mA/mm, a maximum transconductance of gm = 91.3 mS/mm, an FET mobility of 45.3 cm2/V s, and a threshold voltage of −1.75 V. The etching processes developed in this work will enable further development of perovskite oxide heterostructure electronic devices. [ABSTRACT FROM AUTHOR]

Wide and ultrawide bandgap semiconductors can provide excellent performance due to their high energy bandgap, which leads to breakdown electric fields that are more than an order of magnitude higher than conventional silicon electronics. In materials where p-type doping is not available, achieving this high breakdown field in a vertical diode or transistor is very challenging. We propose and demonstrate the use of dielectric heterojunctions that use extreme permittivity materials to achieve a high breakdown field in a unipolar device. We demonstrate the integration of a high permittivity material BaTiO3 with n-type β-Ga2O3 to enable a 5.7 MV/cm average electric field and a 7 MV/cm peak electric field at the device edge while maintaining forward conduction with relatively low on-resistance and voltage loss. The proposed dielectric heterojunction could enable improved design strategies to achieve theoretical device performance limits in wide and ultrawide bandgap semiconductors where bipolar doping is challenging. [ABSTRACT FROM AUTHOR]

The design and modeling of dielectric superjunction transistors using combinations of ultrahigh permittivity materials and high-mobility materials are described. We show that placing high dielectric permittivity materials in the gate–drain depletion region can reduce electric field variations by screening the field due to depleted charges. This enables simultaneously high sheet charge density and breakdown voltage for scaled field-effect transistors. Using detailed 2-D device simulation of dc and high frequency characteristics, we show that extreme dielectric constant engineering provides unique opportunities for transistor design and has the potential to perform better than state-of-the-art millimeter-wave and terahertz frequency transistors. [ABSTRACT FROM AUTHOR]

The sustainability of the anaerobic digestion (AD) plant was closely related to the disposal of digestate and enhancement of energy recovery. Aiming to promote this, coupling AD and digestate gasification (AD-gasification) was proposed and evaluated for a large-scale AD plant. Firstly, characterization of the solid digestate was measured. Secondly, air gasification of the solid digestate was performed. Finally, two scenarios aiming at enhancing energy recovery as electricity or gas were investigated. Superior C content (50.14 wt%), H/C (1.57) and O/C (0.62) molar ratios and lower heating value (LHV) of solid digestate (18.01 MJ/kg) made it propitious to gasification. Air gasification of digestate at 800 °C with ER = 0.26 resulted in the optimal LHV of producer gas (6.35 MJ/Nm3) and cold gas efficiency (CGE, 66.99%). In the biomass-to-electricity scenario, the excess of heat from the CHP system in the AD plant was sufficient to dry the solid digestate. Compared with the stand-alone AD plant, the total electricity from the coupling system increased about 11%. In the biomass-to-gas scenario, the gas income increased by 14% when the initial solid digestate was naturally air-dried to a water content of 50%. This research would provide technical guidance for the sustainability of the AD industry. [ABSTRACT FROM AUTHOR]

The development of biomass gasification is subject to low quality of gas with low heating value and high tar concentration. A new biological pretreatment method by using biogas slurry (BS) with different moisture content (40–80 wt%) and retention time (1–7 days) was advanced for promoting air gasification of corn straw (CS). The considerable NH 4 +-N, appropriate pH and abundant microbes in BS made it effective for CS pretreatment. The dry matter loss of pretreated CS was recorded, the properties of CS and the pretreated CS were comparatively analyzed, and also the kinetic studies. Air gasification experiments were performed in a horizontal tube furnace at 1000 °C. The delignification reaction of BS made disordered and incompact structure of CS with the improved surface area, and decreased the activation energy for chemical reaction. The higher moisture content and longer retention time contributed to the optimal gasification performance. Considering the time and energy conservation, the intermediate 60 wt% moisture content and retention time 5 days was proposed. Compared with the raw CS, the LHV (7.15 MJ/Nm3) increased 1.15 MJ/Nm3, and tar content decreased 21 wt%. This proved efficient and low cost to produce bioenergy from CS, meanwhile, reducing BS and minimizing its potential pollution. • BS was applied for biological pretreatment of CS before air gasification. • Insignificant dry matter loss of all pretreated samples was 1.29 wt%–5.31 wt%. • Intermediate 60 wt% moisture content and retention time 5 days was proposed. • LHV increased 1.15 MJ/Nm3, tar decreased 21 wt%. • Provide new insights for biomass pretreatment and BS disposal [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Stable reduced graphene oxide-cuprous oxide (rGO-Cu 2 O) nanocomposites with long-term antibacterial activities were prepared by reducing copper sulfate supported on GO using ascorbic acid as reducing agent in the presence of polyethylene glycol (PEG) and sodium hydroxide at room temperature. The rGO provided a protective barrier for Cu 2 O, preventing Cu 2 O from reacting with external solution to leach copper ions too quickly. Meanwhile, the rGO also promoted the separation of photoexcited charge carriers of Cu 2 O nanoparticles to enhance the oxidative stress reactive and protected Cu 2 O from falling apart in the phosphate buffered solution (PBS) solution to prolong the generation time of reactive oxygen species (ROS). More importantly, the large specific surface area of rGO improved the dispersibility of Cu 2 O by electrostatic interaction. The synergistic effect of sustained release of copper ions, elevated ROS production ability and uniform dispersion of rGO-Cu 2 O nanocomposites resulted in the excellent antibacterial activities of rGO-Cu 2 O nanocomposites against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) which were maintained around 70% and 65% and were increased by 40% and 35% compared with free Cu 2 O after immersing 30 days in PBS solutions. [ABSTRACT FROM AUTHOR]

Introduction: Postpartum endometritis is a prevalent reproductive disorder in bovines, leading to a prolonged open period, infertility, and other complications. While Lactobacillus strains can mitigate these conditions by reducing uterine inflammation, their effectiveness is limited due to a lack of direct anti microbial action and extended treatment duration. This study aimed to construct a recombinant Lactobacillus johnsonii strain expressing bovine Granulocyte-macrophage colony-stimulating factor (GM-CSF) to evaluate its potential in reducing postpartum uterine inflammation., Methods: The recombinant Lactobacillus johnsonii strain was engineered to express bovine GM-CSF and administered to pregnant mice via vaginal perfusion. Postpartum endometritis was induced using E. coli infection, and the protective effects of the engineered strain were assessed. Inflammatory markers (IL-6, IL-1β, TNF-α), myeloperoxidase (MPO) activity, and nitric oxide (NO) concentration were measured. Histological examination was performed to evaluate uterine morphology and pathological damage., Results: The recombinant L. johnsonii strain expressing GM-CSF significantly reduced inflammation levels induced by E. coli infection in the uterus. This reduction was evidenced by decreased expression of IL-6, IL-1β, TNF-α, as well as reduced MPO activity and NO concentration. Histological examination revealed improved uterine morphology and reduced pathological damage in mice treated with the recombinant GM-CSF strain. Crucially, the recombinant strain also exerts beneficial effects on bovine endometritis by reducing levels of inflammatory cytokines, suggesting a beneficial effect on clinical bovine endometritis., Conclusion: The recombinant Lactobacillus johnsonii expressing GM-CSF demonstrated protective effects against postpartum endometritis in bovines by reducing inflammatory cytokines. The findings indicate the potential clinical application of this engineered strain in preventing postpartum uterine inflammation, offering a novel and effective protective option for related disorders and improving bovine reproductive efficiency., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Guo, Cao, Li, Wang, Zhong, Wang, Fan, Zhao, Wang, Fang, Liu, Ding, Ma and Lu.)

Background: Pregnancy-induced hypertension is a common complication in obstetrics and an important cause of maternal death. We explored the correlations among stress, family function and coping mode in women with pregnancy-induced hypertension syndrome., Methods: A total of 58 pregnant women with pregnancy-induced hypertension syndrome were included in the study. The perceived stress scale (PSS), family assessment device (FAD), and medical coping modes questionnaire (MCMQ) were used to assess stress level, family function, and coping mode, respectively., Results: The PSS score was 28 (interquartile range: 20-43). The total FAD score was 128.1±27.1. The subscale scores were problem-solving, affective responsiveness, communication, roles, behavior control, affective involvement, and general function, in order of decreasing score. Significant correlations were noted between PSS score and total FAD score, affective responsiveness, problem-solving, communication, roles, affective involvement, and behavior control (all P<0.05). PSS score was significantly correlated with "Escape" (P=0.016) and "Yield" (P<0.001) in the MCMQ. Single-factor analysis showed that education level, average household income, and FAD total score were significantly different in those with a low or high PSS score. Logistic regression indicated the FAD total score as an independent factor for the PSS score., Conclusions: Women with pregnancy-induced hypertension syndrome with a high PSS score tended to adopt the "Escape" and "Yield" coping modes. Family function integrity is essential for reducing PSS scores.