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Nicotinamide adenine dinucleotide (NAD) is essential for cellular physiological processes, directly or indirectly affecting metabolism and gene expression. The decline of NAD+ levels in the heart is accompanied by aging, causing cardiac pathological remodeling and dysfunction. Niacinamide mononucleotide (NMN) has emerged as a precursor to alleviate age-related cardiac pathophysiological changes by improving cardiac NAD+ homeostasis. Preclinical trials on the efficacy and safety of intaking NMN have shown encouraging results, revealing a cardioprotective effect without significant side effects. Strategies for improving the effectiveness of NMN are also evolving. The present review aimed to summarize the potentials of NMN as a nutraceutical against cardiac aging and highlight the relationship between NMN supplementation and cardiac protection. [ABSTRACT FROM AUTHOR]

This research investigates the synergistic enhancement of semiconductor catalysts through the incorporation of carbon quantum dots (CQDs) within CeO 2 -Fe 3 O 4 Type-II heterojunction photocatalysts. Subsequent to the successful synthesis of these modified photocatalysts, a thorough assessment of their catalytic performance is conducted. Notably, the introduction of CQDs results in a 21% increase in pollutant degradation capacity compared to unmodified heterojunctions, with a remarkable removal efficiency of 96% for the target pollutant TC. Comprehensive analyses employing electrochemical impedance spectroscopy (EIS), UV–vis spectroscopy, and photocatalytic experiments provide substantial evidence for the efficacy of CQDs in enhancing light absorption properties within the CeO 2 -Fe 3 O 4 heterojunction. This enhancement is attributed to a notable suppression of electron-hole pair recombination, facilitating the generation of reactive oxygen species (ROS) such as ·O 2 - and ·OH. This, in turn, the promotion of Ce4+/Ce3+ and Fe3+/Fe2+ cycles takes place, collectively enhancing the responsiveness of the photocatalyst to visible light. The photocatalysts demonstrate enduring catalytic and magnetic stability over five cycles, as indicated by the sustained high-performance retention. Detailed analysis using TOF-LC-MS has revealed two highly efficient degradation pathways for the for the target pollutant. The findings contribute valuable insights for advancing the performance of heterojunction photocatalysts. [Display omitted] • A green method for synthesizing biomass CQDs photocatalysis was developed. • Modification of the heterojunction with biomass CQDs boosts catalytic activity. • Biomass CQDs promotes the orderly separation of electrons and holes. • The visible light response is effectively improved by CQDs. [ABSTRACT FROM AUTHOR]

The closed working condition of grouting materials leads to insufficient curing water supply during their strength development. In this work, the superabsorbent polymer (SAP) was used as the internal curing agent for grouting material. The effects of SAP content on the rheological and mechanical properties of grouting material were studied under various water-cement ratios (w/c) and curing environments. The time-dependent variation of fresh slurry's viscosity was measured by Brinell viscometer. The pore structure and micromorphology characteristics were analyzed by Mercury Intrusion Porosimetry (MIP) and Scanning Electron Microscope (SEM). The results indicate that the addition of SAP increases the viscosity of fresh slurry and decreases its fluidity, thereby improving the slurry's internal uniformity at a higher w/c. And in its actual working condition, grouting material's strength can be boosted with less than 0.3% SAP dosage. Although SAP will introduce some irregular mesoscopic pores (0.2 − 0.3 mm), the MIP data analysis proves SAP refines the microscopic pore structure of grouting materials. SEM data analysis proves SAP optimizes the microstructure of grouting material, which cured in dry environment. In general, SAP improves the internal uniformity of grouting material by absorbing excess mixing water and gradually releasing it to promote cement hydration, which improves the strength of grouting material. Hence, SAP is a practicable internal curing agent for grouting material and 0.2% is the recommended dosage. • Investigations were done on how SAP affected grouting material performance. • SAP increases the viscosity and improves the internal uniformity of the slurry. • SAP optimizes the microscopic pore structure of the material. • SAP demonstrates a good internal curing effect in sealed and dry environments. [ABSTRACT FROM AUTHOR]

Periodic changes in temperature commonly occur diurnally and seasonally. However, the response of soil heterotrophic respiration to rising and decreasing temperatures during these periods remains poorly understood; thus the feedback between climate change and carbon (C) cycling requires further investigation. In this study, soils from three grasslands in the Qinghai-Tibet Plateau were incubated separately at rising (from 5 °C to 31 °C) and decreasing (from 31 °C to 5 °C) temperatures modes over 161 days, to explore how soil heterotrophic respiration rates ( R S ) respond to different temperature changes. The parameters of R S and temperature sensitivity ( Q 10 ) were used for the analyses. In addition, microbial biomass C (MBC), microbial biomass nitrogen (N) (MBN), dissolved organic C (DOC), and other soil properties were measured. The results indicated a pronounced hysteresis of R S for both rising and decreasing temperatures. Furthermore, the hysteresis loops differed in the different sites. R S values were significantly higher for rising temperature (2.71 μg C g −1 d −1 ) versus decreasing temperature (1.75 μg C g −1 d −1 ) in all three alpine grasslands. The Q 10 values were significantly higher for decreasing temperature (2.42) versus increasing temperature (1.55), with these differences being observed over the 161-d incubation period. Furthermore, soil microbes (specifically, MBC and MBC/MBN) explained 46–77% of the total variation in Q 10 , followed by substrate and other properties. Our results provide experimental evidence for the asymmetric responses of soil heterotrophic respiration to rising and decreasing temperatures. In addition, the microbial effect was primarily associated with soil heterotrophic respiration, suggesting strong asymmetric responses to rising and decreasing temperatures that require investigation in future studies. [ABSTRACT FROM AUTHOR]

Heterojunction photocatalysts Fe 2 O 3 –ZnO@C/g-C 3 N 4 (FZCCN) were prepared by precipitation and calcination in this study. Systematic characterization demonstrated that the tight interfacial contact was established between Fe 2 O 3 –ZnO@C and g-C 3 N 4 , and the FZCCN-4 (theoretical mass ratios of ZnO and g-C 3 N 4 was 4) had large BET surface area (110.136 m2 g−1). Bisphenol A (BPA) was selected to estimate the photocatalytic properties of FZCCN and the degradation reaction kinetics was analyzed at the same time. The results showed that, FZCCN-4 had the highest removal rate of BPA (100%, 60 min). The degradation rate of BPA by using FZCCN-4 was approximately 32 and 130 times higher than that of g-C 3 N 4 and Fe 2 O 3 –ZnO@C, respectively. ·O 2 − was proved to be the main active species by capture experiment and electron spin resonance. The UV–vis and PL results proved the formation of heterojunction in FZCCN. This study also identified the intermediates of BPA degradation and tested their toxicity. The excellent visible light catalytic performance of Fe 2 O 3 –ZnO@C/g-C 3 N 4 makes it an ideal material for degrading contaminants. [Display omitted] • The heterojunction photocatalyst Fe 2 O 3 –ZnO@C/g-C 3 N 4 was synthesized. • The Fe 2 O 3 –ZnO@C/g-C 3 N 4 catalyst had a large specific surface area. • The catalyst presented efficient removal performance of BPA. • The catalyst had a good adaptability in the range of pH = 5.0–10.0. [ABSTRACT FROM AUTHOR]

For layered half spaces in which the shear wave (S-wave) velocity of layer increases with the layer depth, the subsurface seismic wave field generated by surface sources is dominated by the fundamental mode Rayleigh waves (R-waves). When a cavity full of air is present in the underlying half space, the forward (or incident) R-waves are scattered. The scattered wave field in front of the cavity is dominated by the back-scattered R-waves and the interference fringes are formed. Under the conditions that the length (i.e. horizontal extent) of cavity is enough large relative to the wavelength and the burial depth, the majority of the diffracted waves over the cavity approach the fundamental mode plate waves. The displacement structures (variations of displacement with depth) of the diffracted waves are different from those of R-waves within the burial depth. The differences could result in the decrease of the spectral amplitude over the cavity relative to that in front of the cavity. In the surface wave-field behind the cavity, the diffracted waves under the cavity could cause the increase of the spectral amplitude relative to that over the cavity at some low frequencies. By transforming the spectrum into the wavelength domain, a method is proposed to estimate the horizontal extent and burial depth of a cavity from the spectral changes in the offset-wavelength domain. The feasibility is verified by a preliminary experiment. ∙ The normalized depth of energy distribution in a layered half space is smaller than that in a half space with the Poisson's ratio equal to that of the first layer. ∙The majority of the diffracted waves over a cavity behave as the fundamental mode plate waves under conditions that the length of cavity is large compared to the wavelength and the burial depth. ∙The spectral changes over a cavity are explained using displacement structure differences between R-waves and the diffracted waves. ∙The spectral density over a cavity is weaker than that in front of the cavity. ∙In the wave field behind a cavity, the frequency content relatively increases for the waves with the wavelengths larger than the burial depth. ∙The location and burial depth of cavity can be estimated from the spectral changes in front of and behind a cavity in the offset-wavelength domain. [ABSTRACT FROM AUTHOR]

Abstract: In layered soils, there are multiple modes in the surface-wave field. The vibrations of these modes interfere constructively or destructively with each other. The phase velocity (i.e. the effective phase velocity) of the superposed particle vibration is different from those of the modes. Because of limitations in the current data acquisition methods in geotechnical engineering tests, the modes are not easily separated and the experimental dispersion data are often corresponding to the effective phase velocity. In the present work, the relationship between the effective phase velocity and the phase velocities of the natural modes (i.e. the modes of planar Rayleigh waves under the natural state) is established by using the thin layer stiffness matrix method. Effects of higher modes and the mode incompatibility on the effective phase velocity are analyzed for three typical layered media. The results show that influenced by both the higher modes and the mode incompatibility, the effective phase velocity depends not only on the frequency but also on the offset. Effects of changes in soil properties such as the density, Poisson’s ratio and the damping ratio, on the effective phase velocity are investigated. The analyses indicate that changes in the density and the material damping ratio have negligible influences on the effective phase velocity and dispersion of modes, whereas change in Poisson’s ratio shows relatively obvious influences in the case that a stiffer layer is trapped into two soft layers. The results are helpful for reducing the non-uniqueness in the back analysis of the experimental dispersion data. [Copyright &y& Elsevier]

Abstract: The synthesis of dihydropyrimidinones via a clean multi-component Biginelli reaction under microwave irradiation is reported. The copper-catalyzed process proved to be simple, efficient, economical, and environmentally friendly. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) play key regulatory roles in a number of biological processes, which act as critical biomarkers for clinical diagnosis. There are urgent needs to develop advanced tools for accurate and convenient analysis of miRNA in biological circumstances. In this study, an ultrasensitive electrochemical biosensor for miRNA assay is fabricated. Tetrahedral DNA modified gold nanoparticles tags are applied with optimized orientation, which are able to recruit a large number of electrochemical species for remarkable signal responses. Benefiting from the excellent amplification efficiency of the association of strand displacement amplification and catalyzed hairpin assembly, the established method shows ultrahigh sensitivity with the limit of detection as low as 10 aM. A wide linear range from 10−17 to 10−7 M is achieved. In addition, this method is capable to specifically discriminate interfering miRNAs with slightly different sequences. The successful assessment of miRNA levels in human serum samples also demonstrates good practical utility. Therefore, the proposed method has great potential to the applications of miRNA expression profiling and biological studies. [Display omitted] • An ultrasensitive electrochemical biosensor for the detection of miRNA is developed. • Tetrahedral DNA modified AuNPs tags are applied for signal enhancement. • The electrochemical method successfully distinguishes target miRNA from mismatched miRNAs. • The electrochemical method performs satisfactorily in clinical samples. [ABSTRACT FROM AUTHOR]

Although the thermal decomposition of nitrocellulose (NC) has been comprehensively examined, the effects of nitrogen content on the pyrolysis behavior of NC have not been clearly elucidated. In this work, the macro- and microstructures of NC samples with varying nitrogen contents were qualitatively and quantitatively analyzed. Higher nitrogen contents in NC samples were found to be associated with an increased number of nitro groups and cracks in the fiber surface. To elucidate the NC pyrolysis process and provide a theoretical basis for enhancing its stability, the pyrolytic behavior of NC was examined using thermogravimetric analysis-Fourier transform infrared spectrometry and pyrolysis-gas chromatography-mass spectrometry. The pyrolysis of NC primarily occurred within a temperature range of 180–240 °C; however, the peak temperature of the mass loss rate decreased with increasing nitrogen content. The initial nitrogen oxide produced by pyrolysis was nitrogen dioxide (NO 2). During the main stage of pyrolysis, a wider variety of gases was produced by NC having a higher nitrogen content, with more cyclization recombination forms occurring in the post-reaction stage of pyrolysis. Based on the findings of this study, a detailed process of NC pyrolysis has been proposed. [ABSTRACT FROM AUTHOR]

• Established a novel driver-level risk modeling framework based on the temporal variation characteristics of driving behavior. • Proposed "traffic entropy" index to regularize heterogeneous driving behavior. • Utilized deep learning models to conduct the temporal variation feature mining for critical safety management driver identification. • Developed a convolutional neural network (CNN) model based on time-series traffic entropy data, achieving an AUC index of 0.754. • Evaluated the influence of risk factors on driver-level risks. Identifying critical safety management drivers with high driver-level risks is essential for traffic safety improvement. Previous studies commonly evaluated driver-level risks based upon aggregated statistical characteristics (e.g., driving exposure and driving behavior), which were obtained from long-period driving monitoring data. However, given the great advancements of the connected vehicle and in-vehicle data instrumentation technologies, there has been a notable increase in the collection of short-period driving data, which has emerged as a prominent data source for analysis. In this data environment, traditionally employed aggregated behavior characteristics are unstable due to the time-varying feature of driving behavior coupled with insufficient data sampling periods. Thus, traditional modeling methods based upon aggregated statistical characteristics are no longer feasible. Instead of utilizing such unreliable statistical information to represent driver-level risks, this study employed temporal variation characteristics of driving behavior to identify critical safety management drivers in the short-period driving data environment. Specifically, the relationships between driving behavior temporal variation characteristics and individual crash occurrence probability were developed. To eliminate the impacts of drivers' driving behavior heterogeneity on model performance, "traffic entropy" index that could quantify the abnormal degrees of driving behavior was proposed. Deep learning models including convolutional neural network (CNN) and long short-term memory (LSTM) were employed to conduct the temporal variation feature mining. Empirical analyses were conducted using data obtained from online ride-hailing services. Experiment results showed that temporal variation characteristics based models outperformed traditional aggregated statistical characteristics based models. The area under the curve (AUC) index was improved by 4.1%. And the proposed traffic entropy index further enhanced the model performance by 5.3%. The best model achieved an AUC of 0.754, comparable to existing approaches utilizing long-period driving data. Finally, applications of the proposed method in driver management program development and its further investigations have been discussed. [ABSTRACT FROM AUTHOR]

Abstract Carbonaceous materials derived from a variety of cheap and sustainable biomass have shown great potential as conductive substrates for the coating of pseudocapacitive materials. In this study, yeast-derived N-doped carbon microsphere/polyaniline (YC/PANI) composites are synthesized by an in situ polymerization approach, using yeasts as the carbon source and structural template. The self-templated hollow YC with good conductivity has many active sites for anchoring PANI, and alleviates the structure destruction caused by the redox reaction of PANI. Accordingly, the YC/polyaniline composite as a supercapacitor electrode exhibits a high specific capacitance (500 F g−1 at a current density of 1 A g−1) and good rate capability in a three-electrode system. Additionally, the symmetric supercapacitor of the YC/polyaniline composite delivers a high capacitance (100 F g−1 at 1 A g−1) and remarkable cycle life (95.4% of the initial capacitance maintenance after 5000 cycles). The uniform coating of PANI nanowires and robust structure stability of composites are responsible for excellent electrochemical properties. Graphical abstract Image 1 Highlights • Yeast-derived carbon microsphere/polyaniline composites are synthesized as electrode materials for supercapacitors. • The optimized electrode exhibits a high specific capacitance and a favorable rate capability. • The hollow and robust microspherical architecture of the composite ensures the long-term cycling stability. [ABSTRACT FROM AUTHOR]