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The global production of furfural generates substantial amounts of furfural residue waste annually, which, if not properly managed, can lead to significant environmental pollution. However, the ash produced from the combustion of this biomass waste shows promise as a cement additive, offering an innovative solution for furfural residue management. In this study, ash obtained from the combustion of furfural residue in industrial boilers was used as an additive in both Portland cement and magnesium oxysulfate cement, with concentrations ranging from 5% to 20%. Mortar specimens were then prepared and tested for compressive and flexural strength at 3, 7, and 28 days. The results indicated that at a 10 wt% addition, the formation of cotton-like structures and ettringite needles was most pronounced, resulting in the highest compressive and flexural strengths in the Portland cement specimens. Similarly, in magnesium oxysulfate cement, a 10 wt% ash addition significantly promoted the formation of the 5·1·7 phase, leading to the highest compressive strength. In summary, under appropriate conditions, furfural residue ash can be effectively utilized as a cement additive, contributing to resource recovery and sustainable waste management.

Abstract Accurately and quickly predicting hydrogen embrittlement performance is critical for the service of metal materials. However, due to multi‐source heterogeneity, existing hydrogen embrittlement data are missing, making it impractical to train reliable machine learning models. In this study, we proposed an ensemble learning training strategy for missing data based on the Adaboost algorithm. This method introduced a mask matrix with missing data and enabled each round of training to generate sub‐datasets, considering missing value information. The strategy first trained a subset of features based on the existing dataset and a selected method and continuously focused on the combination of features with the highest error for iterative training, where the mask matrix of the missing data was used as the input to fit the weights of each base learner using a neural network. Compared with directly modeling on highly sparse data, the predictive ability of this strategy was significantly improved by approximately 20%. In addition, in the testing of new samples, the predicted mean absolute error of the new model was successfully reduced from 0.2 to 0.09. This strategy offers good adaptability to the hydrogen embrittlement sensitivity of different sizes and can avoid interference from feature importance caused by filling data.

The voluminous generation of distilled spirits lees (DSL) in China presents a challenge for proper disposal and potential environmental pollution. In an effort to address this issue, this study aimed to find a resourceful solution for DSL utilization. The application of incinerated rice husk ash as a mortar supplementary material in cement provides an innovative solution for the disposal of DSL. Five samples of distilled spirits lees ash (DSLA) were produced using both muffle furnace (MF) and fluidized bed (FB) combustion at different temperatures. The properties of DSLA were characterized through measurements of specific surface area and observations using scanning electron microscopy (SEM). Mortar specimens were prepared by replacing 10% of cement with DSLA, and strength tests were conducted. The SEM results revealed the crisscross mesh structures in the DSLA samples. Additionally, the findings indicated a strong connection between the specific surface areas and the micromorphology. In this work, all DSLA samples, except for the one produced in FB at 800 °C, could improve compressive and flexural strengths in the prepared mortar specimens and were suitable for employment as cement additives.

In recent decades, antimicrobial peptides (AMPs) have held great promise as novel antibiotic agents. However, they have generally been excluded from clinical use due to certain limitations, such as poor biocompatibility and sensitivity to environmental conditions. In this study, we report a novel brevinin-1 type antimicrobial peptide B1LTe, derived from the skin secretion of Hylarana latouchii. Although the novel peptide B1LTe exhibited remarkable antimicrobial effects, its narrow therapeutic index (TI) can result in adverse drug reactions. Thus, the rational design by systematically scanning and replacing the inherent hydrophobic and cationic residues (Leucine and Lysine) with their D-enantiomeric counterparts was conducted to enhance the application potential of B1LTe. Simultaneously, we also applied lysine-to-arginine substitution within the modification. Among the derivates, 5 R demonstrated the highest selectivity and effectiveness against Methicillin-resistant Streptococcus aureus (MRSA), clinic-isolated Streptococcus pyogenes (S. pyogenes) strain, ranging from their planktonic to biofilm cells, both in vitro and in vivo. Furthermore, the remarkable adaptation of 5 R in saline and 20% serum indicates its potential for clinical application. We employed the in silico approach, which revealed the mechanism of interaction between 5 R and bacterial membranes. In addition, further mechanistic studies of 5 R elucidated the association between the collapsed proton motive force (PMF) and membrane perturbation as peptides aggregate on the bacterial membrane. Overall, our study suggests the D-enantiomeric 5 R can be a promising antibiotic agent against MDR bacteria in further clinical development and highlights the significance of cellular PMF as a potential target for the research of peptides’ mode of action.

Long-term (2005–2021) observations from the World Wide Lightning Location Network reveal significantly larger flash counts over heavily trafficked shipping lanes in the northeastern Indian Ocean compared to nearby regions. Here, we use the online coupled meteorology-chemistry model WRF-Chem to examine the impact of aerosols from shipping emissions on lightning activity over one of the world’s busiest shipping lanes (5–7° N, 82–92° E). We conduct three case simulations in January 2013, 2015, and 2018 when frequent lightning activities were recorded. The WRF-Chem model with lightning parameterized based on convective cloud-top height captures the temporal evolution of lightning activities but overestimates the magnitude of lightning counts. We find that all three cases consistently show enhanced lightning flash counts due to shipping-induced aerosols by 6.2%–22.3%, accompanied by increased cloud droplet number, cloud water concentration, radar reflectivity, and cloud-top height. Sensitivity simulations show that aerosol-cloud-interactions from shipping aerosols consistently enhance the strength of convection and lightning frequency in all three cases, by increasing cloud condensation nuclei and cloud droplet numbers, delaying precipitation of cloud water, allowing the lift and accumulation of water vapor, increasing release of latent heat, and finally invigorating convections. In comparison, aerosol-radiation-interactions show inconsistent contributions to convection and lightning, which enhance lightning frequency in the 2013 and 2015 cases but decrease lightning frequency in the 2018 case. This inconsistency may be attributed to differences in the number and vertical structure of shipping aerosols and cloud droplet in the three cases. Our study thus approves the certain but complicated anthropogenic impacts on lightning activities through shipping-induced aerosols, which has important implications for understanding future trends in lightning and its impact on atmospheric chemistry and climate.

This work carried out the experimental investigation and model analysis on a GaN electrostatic discharge (ESD) clamp, which features a discharge high electron mobility transistor (HEMT) and a voltage divider formed by a lateral field effect rectifier (L-FER) chain and a resistor in series. Firstly, it is found through the experimental investigation, the turn-on voltage ( $V_{\mathrm {T}}$ ) of GaN ESD clamp’s static current is increased with the increase in L-FER’s number and the decrease in resistor’s value. Then, an analytical model is proposed to analyze the dependence of $V_{\mathrm {T}}$ on L-FER’s number and resistor’s value. And the analytical model exhibits a good consistency with the experimentally measured results, which confirms the validity of the presented analytical model. Lastly, the dependence of GaN ESD clamp’s transmission line pulsing characteristics on the L-FER’s number and resistor’s value is also analyzed. Similarly, GaN ESD clamp’s triggering voltage is also increased with the increase in L-FER’s number and the decrease in resistor’s value. The experimental investigation and model analysis of this work can be used to direct the design of GaN ESD clamp, and help to save a lot of manpower, material resources and time costs.

The hydrogen-based hollow fiber membrane biofilm reactor (H2-based MBfR) has shown to be a promising technology for nitrate (NO3––N) reduction. Hollow fiber membranes (HFM) operating in a closed mode in an H2-based MBfR often suffer from reverse gas diffusion, taking up space for the effective gas substrate and resulting in a reduction in the HFM diffusion efficiency, which in turn affects denitrification performance. In this work, we developed a laboratory-scale H2-based MBfR, which operated in a closed mode to investigate the dynamics of denitrification performance and biofilm microbial community analysis at different H2 supply pressures. A faster formation of biofilm on the HFM and a shorter start-up period were found for a higher H2 supply pressure. An increase in the H2 pressure under 0.08 MPa could significantly promote denitrification, while a minor increase in denitrification was observed once the H2 pressure was over 0.08 MPa. Sequencing analysis of the biofilm concluded that (i) the dominant phylum-level bacteria in the reactor during the regulated hydrogen pressure phase were Gammaproteobacteria and Alphaproteobacteria; (ii) when the hydrogen pressure was 0.04–0.06 MPa, the dominant bacteria in the MBfR were mainly enriched on the hollow fiber membrane near the upper location (Gas inlet). With a gradual increase in the hydrogen pressure, the enrichment area of the dominant bacteria in MBfR gradually changed from the upper location to the distal end of the inlet. When the hydrogen pressure was 0.10 MPa, the dominant bacteria were mainly enriched on the hollow fiber membrane in the down location of the MBfR.

High frequency and high efficiency operation is one of the premier interests in the signal and energy conversion applications. The wide bandgap GaN based devices possess superior properties and have demonstrated exceeding performance than Si or GaAs devices. In order to further exploit the potential of GaN electronics, monolithic power integration is proposed. Firstly, this paper discusses the structure and properties of GaN power devices to explain the choice of lateral integration in the view of GaN power ICs. Then the state-of-the-art performance of GaN power integration in two major application areas is reviewed, which are the microwave power amplification and DC-DC power conversion. The GaN power integration technologies in MMIC platforms are summarized in terms of the gate length, operation frequency and power added efficiency of ICs. On the other hand, the smart GaN power IC platforms have boosted the development of DC-DC power converters. Demonstrations of high frequency (>1 MHz) and high efficiency (>95 %) converters with various kinds of integration technology and topology are reviewed. Lastly novel integration schemes and methods are introduced to stimulate new thoughts on GaN power integration road.

Antimicrobial peptides (AMPs) from wasp venom have a good track record and potential for drug development as tools against development of antimicrobial resistance. Herein, the biological function and activity profile of peptide VM, which was discovered in the venom of the wasp, Vespamandarinia, and several of its third-position substituted analogues, were investigated. VM had potent antimicrobial activity against Gram-positive bacteria and biofilm, and all modified peptides achieved the significant enhancement of these capacities. The various physicochemical properties of amino acids substituted in analogues, generated the different mechanisms of action of bacterial membrane disruption. VM-3K showed a maximum 8-fold enhancement of antibacterial activity against Gram-positive bacteria and also presented microbicidal properties against Gram-negative bacteria and fungi. This peptide also exhibited a high killing efficiency at low concentration and had a comparable selectivity index to VM. Furthermore, VM-3K produced a 90% survival of S. aureus-infected waxworms at a concentration of 5.656 mg/kg, at which concentration the natural template peptide only achieved 50% survival. This peptide also lacked short-term resistance generation. Thus, peptide VM-3K could be a promising broad-spectrum antimicrobial candidate for addressing the current antibiotic-resistant infection crisis. It is worth mentioning that this investigation on the relationship between peptide structure and mechanism of action could become an important aspect of drug research on short peptides.

Zinc, an essential micronutrient for life, was first discovered in 1869 and later found to be indispensable for the normal development of plants and for the normal growth of rats and birds. Zinc plays an important role in many physiological and pathological processes in normal mammalian brain development, especially in the development of the central nervous system. Zinc deficiency can lead to neurodegenerative diseases, mental abnormalities, sleep disorders, tumors, vascular diseases, and other pathological conditions, which can cause cognitive impairment and premature aging. This study aimed to review the important effects of zinc and zinc-associated proteins in cognitive impairment and aging, to reveal its molecular mechanism, and to highlight potential interventions for zinc-associated aging and cognitive impairments.

This paper presents a GaN based synchronous buck DC-DC converter, which monolithically integrates gate drivers and a half-bridge power stage in a 3-μm enhancement-mode (E-mode) GaN-on-Si process. The fabricated synchronous converter with integrated gate drivers is based on E-mode GaN MIS-HFETs (metal-insulator-semiconductor heterojunction-field-effect-transistors), which have a large gate swing of 10 V due to the insertion of 20 nm high-k gate insulator Al2O3. At 100 kHz, the proposed DC-DC integrated circuits (ICs) exhibit good thermal stability at high temperatures up to 250 °C for 25 V down conversion. Furthermore, four different designs (asynchronous and synchronous) including converters with external drivers were systematically evaluated at different input voltages and duty cycles, the GaN-based DC-DC converters with integrated gate drivers exhibit small voltage overshoots and oscillations due to reduced parasitic inductance and chip size. These results validate the advantages of monolithic, lateral integration of half-bridge GaN ICs with gate drivers for high temperature power converters.

Given its increasing prevalence, aging is of great concern to researchers worldwide. Cellular senescence is a physiological or pathological cellular state caused by aging and a prominent risk factor for the interruption of the integrity and functionality of human biological barriers. Health barriers play an important role in maintaining microenvironmental homeostasis within the body. The senescence of barrier cells leads to barrier dysfunction and age-related diseases. Cellular senescence has been reported to be a key target for the prevention of age-related barrier diseases, including Alzheimer's disease, Parkinson's disease, age-related macular degeneration, diabetic retinopathy, and preeclampsia. Drugs such as metformin, dasatinib, quercetin, BCL-2 inhibitors, and rapamycin have been shown to intervene in cellular senescence and age-related diseases. In this review, we conclude that cellular senescence is involved in age-related biological barrier impairment. We further outline the cellular pathways and mechanisms underlying barrier impairment caused by cellular senescence and describe age-related barrier diseases associated with senescent cells. Finally, we summarize the currently used anti-senescence pharmacological interventions and discuss their therapeutic potential for preventing age-related barrier diseases. [ABSTRACT FROM AUTHOR]