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Diabetic wounds are difficult to heal because of persistent inflammation and limited angiogenesis. Resveratrol (RES) is an anti-inflammatory and antioxidant agent. Platelet-derived extracellular vesicles (PDEVs) are rich in growth factors and cytokines, which promote proliferation and angiogenesis. However, single drug treatment has limited efficacy and delivery efficiency. Bioengineering can improve the limited effect of single drugs by combining drugs and materials to obtain complementary or cooperative bioengineered drugs. In this study, gelatin methacrylate (GelMA) and silk fibroin glycidyl methacrylate (SFMA) were used to synthesize GelMA/SFMA composite hydrogels with suitable mechanical properties, swelling ratio and biodegradability. The composite hydrogel was used as a wound dressing for sustained drug release. RES was loaded into mesoporous silica nanoparticles (MSNs) to synthesize MSN-RES to enhance the release dynamic, and MSN-RES and PDEVs were combined with the composite hydrogels to form GelMA/SFMA/MSN-RES/PDEVs hydrogels. The GelMA/SFMA/MSN-RES/PDEVs had low cytotoxicity and good biocompatibility, inhibited macrophage iNOS expression, and promoted the tube formation by human umbilical vein endothelial cells (HUVECs) in vitro. In a diabetic mouse wound model, the GelMA/SFMA/MSN-RES/PDEVs hydrogels decreased the expression of pro-inflammatory factors TNF-α and iNOS, increased the expression of anti-inflammatory factors TGF-β1 and Arg-1, promoted angiogenesis, and accelerated wound healing. Interestingly, the GelMA/SFMA/MSN-RES/PDEVs hydrogels promoted the expression of extracellular purinergic signaling pathway-related CD73 and adenosine 2A receptor (A2A-R). Therefore, the GelMA/SFMA/MSN-RES/PDEVs hydrogels could be used as wound dressings to regulate the inflammation and angiogenesis of diabetic wounds and accelerate wound healing. Drugs often fail to function because of a continuous oxidative stress microenvironment and inflammation. Here, a GelMA/SFMA hydrogel, with enhanced mechanical properties and liquid absorption ability, is proposed for sustained release of drugs. In addition to carrying platelet-derived extracellular vesicles (PDEVs) with pro-angiogenic effects, the hydrogels were also loaded with nanoparticle-encapsulated resveratrol with anti-inflammatory activities, aiming to reduce inflammation and oxidative stress in the wound microenvironment, such that the wound could receive proliferative repair signals to achieve sequential treatment and heal quickly. We also experimentally predicted that the regulatory mechanism of the GelMA/SFMA/MSN-RES/PDEVs in wound healing might be related to the extracellular purinergic signaling pathway. [Display omitted] [ABSTRACT FROM AUTHOR]

Identifying modifiable factors that influence bone status during adulthood to maximize bone quality is a potential primary strategy in the prevention of osteoporosis in later life. We investigated the impact of body height, body weight, body mass index, and body composition on calcaneal bone characteristics as measured with quantitative ultrasound in 441 Chinese adults (238 women) aged 20–55 yr from the middle areas of China. Body composition, including fat-free mass (FFM), muscle mass, and fat mass were obtained by bioelectrical impedance analysis. Bivariate correlation analysis demonstrated a significant negative correlation between age and broadband ultrasound attenuation (BUA), speed of sound (SOS), and stiffness index (SI) both in men (r = −0.177, p  < 0.05; r = −0.499, p  < 0.001; r = −0.530, p  < 0.001, respectively) and women (r = −0.344, p  < 0.001; r = −0.336, p  < 0.001; r = −0.369, p  < 0.001, respectively). Body height, body weight, FFM, and muscle mass had positive correlations with BUA, SOS, and SI in both genders, with FFM having the strongest correlation with BUA, SOS, and SI in men (r = 0.351, p  < 0.001; r = 0.391, p  < 0.001; r = 0.406, p  < 0.001, respectively) and women (r = 0.331, p  < 0.001; r = 0.288, p  < 0.001; r = 0.324, p  < 0.001, respectively). Fat mass had a positive correlation with BUA (r = 0.331, p  < 0.001), SOS (r = 0.288, p  < 0.001), and SI (r = 0.324, p  < 0.001) in women, which was not found in men. Multivariate regression analysis revealed that, in both genders, FFM was a positive predictor for all 3 quantitative ultrasound variables. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has amplified the awareness and demand of public health worldwide. Based on the panel data of 81 developing countries from 2002 to 2019, this study probes into the effect of digitalization on public health and explores the mechanism through which digitalization affects public health from the perspective of income inequality. The results show that digitalization significantly enhances public health in developing countries, and this conclusion still holds after the robustness test. The heterogeneity analysis based on geographic location and income level indicates that the enhancing effect of digitalization on public health is most evident in Africa and middle-income countries. A further mechanism analysis suggests that digitalization can positively impact public health through the intermediary channel of suppressing income inequality. This study enriches the research on digitalization and public health and provides insights for comprehending public health needs and the powerful empowering effects of digitalization. • Digitalization significantly enhances public health in developing countries. • The enhancing effect of digitalization on public health is most evident in Africa and middle-income countries. • Digitalization can exert a positive impact on public health through the intermediary channel of suppressing income inequality. [ABSTRACT FROM AUTHOR]

Abstract: The broadband ultrasound attenuation (BUA) and the speed of sound (SOS) are usually measured to evaluate the bone density. However, as previous studies showed that the BUA is sensitive to repositioning and soft tissue, the reproducibility of measurement will be difficult to achieve. In our system, we used Net Delay Time (NDT) value, pressure detection and several signal-processing techniques to obtain the reproducibility. Through in-vivo examinations, the root-mean square coefficient of variation (CVRMS%) did not significantly change for SOS(about 0.4),BUA (about 2.2).Comparing with the results of other research, we found that the reproducibility of our system was better. [Copyright &y& Elsevier]

X-ray photodiodes made of metal halide perovskites (MHPs) which directly convert X-ray photons into electron-hole pairs have shown advantages in low-cost and high X-ray detection sensitivity. However, lattice-mismatched blocking layers deposited by spin-coating or evaporation cannot fully limit the dark current and noise current under large reverse bias. In this work, Solution-processed dopant incorporated epitaxial growth is employed to form sufficient blocking barriers through epitaxially growing lattice-matched n-type MHPs (bismuth-doped) and p-type MHPs (silver-doped) on opposite faces of intrinsic CH 3 NH 3 PbBr 2.5 Cl 0.5 MHP single crystals. Through energy structure design, electron/hole blocking layers can form sufficient charges barriers, the X-ray PDs exhibit a low leakage dark current density of ~ 11 nA cm−2 under large reverse electrical field (over 500 V cm−1) and noise current of 47 fAHz−0.5 (1 mm2, over 500 V cm−1). The large external electrical field enables a state-of-art response speed (fall) of 750 ns, large X-ray detection sensitivity of 36.0 μ C mGy − 1 c m − 2 and the lowest detectable dose rate of 16 nGys−1(40 kVp). This work will motivate new strategies to fabricate high-performance devices based on perovskites using solution-processed methods. These founding also explore a new generation of low dose and high dynamic X-ray detectors based on MHPs. X-ray PIN photodiode with epitaxially n-type and p-type layers show extremely low dark current under large reverse bias. [Display omitted] • We provide a solution-processed method to epitaxially grow dopant-incorporated perovskite layer. • With lattice-matched epitaxial growth, the defects near the interfaces and inside the epitaxial layers are suppressed. • The X-ray PIN photodiode reported in this work shows remarkable low dark current and noise current. [ABSTRACT FROM AUTHOR]

• Proposes a multi-stage determination method for excavator working points that considers engine fuel consumption, hydraulic pump efficiency, and load fluctuation, overcoming limitations of traditional methods. • Introduces a comprehensive evaluation model for working point determination that integrates fuel consumption, hydraulic pump efficiency, and load variability, offering a more holistic approach. • Utilizes experimental data to inform the determination of engine working points, ensuring practical relevance and applicability. • Employs weight parameters to adjust the importance of fuel consumption and load fluctuation in the working point optimization process, allowing for tailored engine performance improvement under varying operational needs. In view of the problem that the traditional working point determination method only considers the engine fuel consumption and does not consider the hydraulic pump efficiency and load fluctuation in the process of the working point stability control of an excavator engine, a simple and feasible, experimental data-driven, multi-stage determination method of excavator working point based on the comprehensive evaluation model is proposed. In this paper, the comprehensive evaluation model of working point torque with weight parameters is established at different working stages under the rated speed in a phased way. The results show that this method can determine the working point torque at different working stages, and reduce engine fuel consumption and load fluctuation based on ensuring the efficiency of the hydraulic pump. The lowest engine fuel consumption can be reduced by 7.09%, and the lowest load fluctuation can be reduced by 17.8%. In addition, by modifying the weight parameters, we can emphasize the fuel consumption and load fluctuation of the engine according to their importance, to achieve the determination of working points under different requirements. This approach also provides a new idea for optimizing the working point of construction machinery. [ABSTRACT FROM AUTHOR]

• Revealed the damage zone characteristics of different tools penetrating rocks. • Identified the key factors of energy transfer efficiency in impact rock breaking. • Investigated the key influencing factors of the dynamic force-penetration curve. • Proposed a prediction formula for penetration force considering the tool shape. • Evaluated the proportion of energy used for rock cracking. The energy transfer efficiency and damage characteristics are the theoretical basis for the selection and optimization of hydraulic impact hammer tools. In this paper, quarter three-dimensional models of the piston-tool-rock system are established based on the continuum and discontinuum element method. The incident and reflected stress waves and rock damage characteristics obtained from the simulation model are in good agreement with experimental and theoretical results. The effects of piston impact velocity, tool shape, rock strength, confining pressure and repeated impacts on rock damage zone and energy transfer efficiency between tool and rock are analyzed. The force-penetration curves and penetration coefficients under different impact velocities, rock strength, and confining pressure conditions are obtained. The results illustrate that the energy transfer efficiency and penetration coefficient increase with the increase of rock strength, confining pressure and tip area of tool, but decrease with the increase of impact velocity. Based on the simulation results, a prediction formula for penetration force with consideration of the shape of the tool tip is proposed and the calculation accuracy is verified. Finally, the proportion of energy actually used for rock fracturing is analyzed. [ABSTRACT FROM AUTHOR]