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Abstract Recycled aggregate (RA), as a backfill subgrade material, has strong reproducibility and environmental protection, which cannot only effectively reduce resource consumption and environmental pollution but also achieve recycling of resources. Therefore, a study on the bending fatigue performance of RA backfill subgrade is proposed. Based on linear elastic state, softening state, and damage accumulation state, the variation law of bending fatigue damage variables is analyzed, and the stiffness of RA under cyclic load is calculated. According to the correlation between fatigue damage corresponding to two different load links and the constitutive relationship of RA, the identification results of bending fatigue damage state based on RA backfilling subgrade is obtained. The advantages of the fatigue damage model of RA are analyzed, and the fatigue life equation is established based on the damage evolution equation. Strain, stiffness modulus, asphalt saturation, and asphalt mixture adjustment coefficient are selected as model parameters to establish the fatigue damage model of RA. The flexural bearing capacity of the double-reinforced rectangular section is calculated, and the flexural fatigue performance of RA backfill subgrade is analyzed. The test results show that the high stress level in this method leads to a sharp decline in the fatigue life of the specimen, and the influence of fatigue damage gradually appears, which is helpful to improve the durability and safety of the subgrade structure. The range of change shows a small range, which is close to the reduction coefficient result, indicating that this method has high reliability in analyzing the bending fatigue performance of RA backfill subgrade.

This review is a comprehensive overview of recent advancements in underwater in situ heavy metal voltammetric analyzers (UIHVAs). It explores various types of in situ voltammetric analyzers, including the voltammetric in situ profiling system, submersible integrated multi-channel trace metal sensing probes, vibrating gold microwire electrode voltammetric analyzers, and electrochemical analyzers designed for on-site flow measurements. It also covers electrochemical sensors based on flexible liquid crystal polymers, deep-sea mercury sensors, and other in situ electrochemical analyzers. This review systematically examines the research and development progress of microelectrode arrays, screen-printed, carbon, bismuth, antimony, and lab-on-a-chip electrodes. The final section looks at key trends in the research and development of voltammetric analyzers, highlighting the exploration of novel working electrodes, the integration of smart monitoring and data analysis technologies, and the promotion of interdisciplinary collaboration and innovation. From a global perspective, in situ heavy metal voltammetric analysis technology has demonstrated significant applicability in various fields, such as environmental monitoring, marine science, and biogeochemistry. This technology holds considerable potential for further development. However, extensive research and continuous improvement are required to improve detection performance. We are convinced that with continued technological advances and dedicated research efforts, these challenges can be overcome and will pave the way for the widespread application of UIHVAs. [ABSTRACT FROM AUTHOR]

Traditional working electrodes are not sufficient to realize the low detection limit and wide detection range necessary for the detection of heavy metals. In this study, a microelectrode array electrode was proposed using a design scheme based on microelectromechanical systems that was optimized with finite element software. The working electrode adopted an innovative composite structure to realize the integrated design of the working and counter electrodes, which improved the system integration. Performance tests showed that the electrode realized the quantitative analysis of Cd(II), Pb(II), and Cu(II) with a low detection limit (0.1 μg/L) and a wide detection range (0.1–3000 μg/L). The electrode successfully measured the lead and copper ion concentrations in the Sanya River, including both seawater and freshwater environments. The experimental results demonstrate that the electrode exhibits excellent adaptability to environmental conditions and can be potentially applied for technical support in environmental monitoring and sewage treatment. [ABSTRACT FROM AUTHOR]

Liquidambar formosana is a multipurpose tree species native to China. There has been increasing interest in L. formosana due to its leaves being rich in shikimic acid, which plays a key role in the synthesis of the antiviral drug oseltamivir phosphate. Here, shikimic acid content (SAC) and other breeding traits, including tree height (HT), diameter at breast height (DBH), height to crown base (HCB), individual tree volume (VOL), leaf color (LC) and stem straightness degree (SSD), for 387 families of 19 provenances were evaluated in a provenance–family trial of L. formosana to estimate genetic parameters and reveal geographical variation patterns and, ultimately, screen out superior provenances and families. Differences among provenances and families were significant for all tested traits, indicating a high potential for selective breeding. Broad-sense heritabilities of provenance ( h p 2 = 0.19–0.57) and family ( h f 2 = 0.16–0.31) were moderate for most traits. Moderate to strong genetic correlations were found among HT, DBH, VOL, HCB and LC (rA = 0.339–0.982), while adverse correlations (rA = −0.494 to −0.816) were observed between SAC and growth traits. All target traits, excluding SSD, exhibited clinal variation in response to latitudinal gradients, and a clustering heatmap divided the 19 provenances into three groups. For single-trait selection, SAC persistently had the highest genetic gains (85.14%–163.57%). A weighted index based on breeding values was used to concomitantly improve SAC, HT and DBH. At a selection rate of 25%, the genetic gains at the provenance and family levels for SAC were 36.42% and 73.52%, and those for core growth traits ranged from −2.29% to 3.49% and 4.05% to 4.47%, respectively. As far as we know, this is the first study in L. formosana to explore the inheritance of SAC and its correlations with other traditional breeding traits. The genetic parameter estimations contribute to a better understanding of the genetic basis of SAC, and the superior provenances and families obtained lay a material foundation for the development of new varieties rich in shikimic acid, thereby promoting the in-depth exploitation and utilization of germplasm resources of L. formosana. [ABSTRACT FROM AUTHOR]

Long-term in situ measurements of the temperature of hydrothermal fluids have great significance in the research of seafloor hydrothermal activities. Herein, we developed a self-powered battery-free temperature logger for measuring and recording the temperature of hydrothermal fluids. A gravity heat pipe made of titanium alloy was employed as the heat-conducting element of the temperature logger to capture heat from a hydrothermal vent and transfer it to the thermoelectric unit. The thermoelectric generator used herein converted the temperature difference into electrical energy to power the circuit of the temperature logger. Numerical analyses and experiments were performed to investigate the performance of the heat pipe and temperature logger. Results show that the temperature logger can realize self-powered starting at a temperature of >76 °C during a tank test. This paper presents a discussion on a new instrument for temperature measurements of deep-sea hydrothermal fluids. [ABSTRACT FROM AUTHOR]

Macadamia oil cake (MOC) is a type of macadamia nut by‐product, that is extremely rich in amino acids and has beneficial health effects. It lowers blood lipid levels and regulates the intestinal microbiota. MOC effectively attenuated total cholesterol (TC), triglyceride (TG), low‐density lipoprotein cholesterol (LDL‐C), and high‐density lipoprotein cholesterol (HDL‐C) levels in model rats. Depending on the morphology of the colon, MOC can effectively attenuate damage to the tissue structure. The 16S rDNA gene of the rat intestinal microbiota was sequenced using Illumina PE250 high‐throughput sequencing technology, and the changes in the intestinal microbiota in each group are discussed. Supplementing MOC at different doses significantly increased the microbiota of Dorea, Erysipelotrichaceae, Stercoris, etc. in the intestinal tracts of rats fed a high‐fat diet. Therefore, MOC can be included in lipid healthy dietary patterns to lower lipid characteristics and restructure the intestinal microbiota. Future clinical trials are required to determine the therapeutic effects and mechanisms of hypolipidemia. [ABSTRACT FROM AUTHOR]

With the continuous deepening of research on seafloor hydrothermal observations, the demand for a sustainable power supply of observation equipment is increasingly urgent. A kind of device that utilizes the temperature difference near hydrothermal vents to provide power is studied. However, the frequent experiments required for in-depth research on this device contradict the rare opportunities for hydrothermal field experiments and the difficulty in laboratory replication. In response to the above difficulties, a multiphysics co-simulation of the deep-sea hydrothermal energy generation system is studied in this paper. Firstly, the output performance analysis and modeling of the TEG installed in the device under pressure are carried out. An enhanced heat transfer model of the system is proposed for the hydrothermal fluids in the flow channel of the device. Then, the thermoelectric model of TEG and the heat transfer model of the device are jointly simulated by using Fluent and Simulink software. Eventually, the simulation data are compared with the data obtained through experiments. The average absolute of the relative error of the open-circuit voltage is 5.07%, and the maximum one is 6.28%. The corresponding values of the maximum output power are 5.16% and 6.79%, respectively. Therefore, the performance of the hydrothermal thermoelectric power generation system and the correctness of the proposed overall co-simulation model are verified. [ABSTRACT FROM AUTHOR]

The transition areas of riverine, estuarine, and marine environments are particularly valuable for the research of microbial ecology, biogeochemical processes, and other physical–chemical studies. Although a large number of microbial-related studies have been conducted within such systems, the vast majority of sampling have been conducted over a large span of time and distance, which may lead to separate batches of samples receiving interference from different factors, thus increasing or decreasing the variability between samples to some extent. In this study, a new in situ filtration system was used to collect membrane samples from six different sampling sites along the Sanya River, from upstream freshwater to the sea, over a nine-hour period. We used high-throughput sequencing of 16S and 18S rRNA genes to analyze the diversity and composition of prokaryotic and eukaryotic communities. The results showed that the structures of these communities varied according to the different sampling sites. The α-diversity of the prokaryotic and eukaryotic communities both decreased gradually along the downstream course. The structural composition of prokaryotic and eukaryotic communities changed continuously with the direction of river flow; for example, the relative abundances of Rhodobacteraceae and Flavobacteriaceae increased with distance downstream, while Sporichthyaceae and Comamonadaceae decreased. Some prokaryotic taxa, such as Phycisphaeraceae and Chromobacteriaceae, were present nearly exclusively in pure freshwater environments, while some additional prokaryotic taxa, including the SAR86 clade, Clade I, AEGEAN-169 marine group, and Actinomarinaceae, were barely present in pure freshwater environments. The eukaryotic communities were mainly composed of the Chlorellales X, Chlamydomonadales X, Sphaeropleales X, Trebouxiophyceae XX, Annelida XX, and Heteroconchia. The prokaryotic and eukaryotic communities were split into abundant, common, and rare communities for NCM analysis, respectively, and the results showed that assembly of the rare community assembly was more impacted by stochastic processes and less restricted by species dispersal than that of abundant and common microbial communities for both prokaryotes and eukaryotes. Overall, this study provides a valuable reference and new perspectives on microbial ecology during the transition from freshwater rivers to estuaries and the sea. [ABSTRACT FROM AUTHOR]

Monoclinic nano-hydroxylapatite (nHAp) rarely forms at room temperatures, especially from amorphous calcium phosphate (ACP) precursors. We developed a method to synthesise monoclinic nHAp from ACP without crystallisation inhibitors at 25 °C. Additionally, Raman spectroscopy was identified as a reliable technique for observing the crystallisation process. [ABSTRACT FROM AUTHOR]

Novel Pt/Bi3.4Gd0.6Ti3O12 heterojunction was synthesized by a decoration of Pt nanoparticles (PtNPs) on the surface of piezoelectric Bi3.4Gd0.6Ti3O12 (BGTO) through an impregnation process. The photocatalytic, piezo-catalytic, and piezo-photocatalytic activities of the Pt/BGTO heterojunction for methyl orange (MO) degradation were investigated under ultrasonic excitation and whole spectrum light irradiation. The internal piezoelectric field of BGTO and a plasmonic effect have been proven important for the photocatalytic activity of the heterojunctions. Pt/BGTO exhibited an optimum photocatalytic degradation performance of 92% for MO in 70 min under irradiation of whole light spectrum and ultrasonic coexcitation, and this value was about 1.41 times higher than the degradation rate under whole spectrum light irradiation alone. The PtNPs in Pt/BGTO heterojunction can absorb the incident light intensively, and induce the collective oscillation of surface electrons due to the surface plasmon resonance (SPR) effect, thus generating "hot" electron–hole pairs. The internal piezoelectric field produced in BGTO by ultrasonic can promote the separation of SPR-induced "hot" charge carriers and facilitate the production of highly reactive oxidation radicals, thus enhancing Pt/BGTO heterojunction′s photocatalytic activity for oxidizing organic dyes. [ABSTRACT FROM AUTHOR]

Crystalline calcium carbonate (CaCO3, such as calcite) could scavenge aqueous metals via adsorption and coprecipitation. As a precursor to crystalline CaCO3, amorphous calcium carbonate (ACC) is poorly understood on metals removal. Herein, we synthesized silica-stabilized ACC and investigated its Cu2+ removal efficiency and mechanism. The results showed that the Cu2+ removal efficiency by ACC is controlled by the initial solution pH, initial Cu2+ concentration, contacting time, and ACC dosage. The maximum Cu2+ removal capacity was 543.4 mg/g at an ACC dosage of 1 g/L, an initial pH of 5.0, an initial Cu2+ concentration of 1000 mg/L, and an equilibrium time of 20 h. X-ray powder diffraction (XRD) and scanning electron microscope with an energy dispersive spectrometer (SEM-EDS) revealed that Cu2+ precipitated as paratacamite (Cu2(OH)3Cl, space group: R 3 ¯ ) at an ACC dosage of 1 g/L, whereas botallackite (Cu2(OH)3Cl, space group: P21/m) was the Cu-bearing product for crystalline calcite using the same dosage as ACC. However, Cu2+ preferred to incorporate into calcite, which is transformed from ACC at high ACC loading (such as 4 g/L). Our results demonstrated that the crystallinity and dosage of CaCO3 could control the Cu2+ removal mechanism. [ABSTRACT FROM AUTHOR]

Gram-negative bacteria usually use acyl-homoserine lactones (AHLs)-mediated LuxI/LuxR-type quorum sensing (QS) systems for cell-cell cooperation and/or bacteria-environment communication. LuxI and LuxR are AHLs synthase and receptor, respectively. These two parts could form a positive regulatory feedback loop, controlling various types of group behaviors. However, the autoregulation mechanisms between them are fragmented and could be highly differentiated in different bacteria. Here, we clarified the autoregulation mechanism between LuxI and LuxR in Pseudoalteromonas sp. R3. YasI (LuxI in strain R3) synthesizes two types of AHLs, C8-HSL and 3-OH-C8-HSL. It is worth noting that YasR (LuxR in strain R3) only responds to C8-HSL rather than 3-OH-C8-HSL. YasR-C8HSL can activate the yasI transcription by recognizing " lux box" at yasI upstream. Interestingly, YasR can directly promote the yasR expression with AHL-independent manner, but AHL absence caused by the yasI -deficiency led to the significant decrease in the yasR expression. Further study demonstrated that the yasI -deficiency can result in the decrease in the yasR mRNA stability. Notably, both yasI -deficiency and yasR -deficiency led to the significant decrease in the expression of hfq encoding RNA chaperone. Therefore, it was speculated that not only YasR itself can directly regulate the yasR transcription, but YasR-C8HSL complex indirectly affects the yasR mRNA stability by regulating Hfq. [Display omitted] ∙ LuxR-AHLs in Pseudoalteromonas can activate the yasI transcription by recognizing " lux box". ∙LuxR can directly promote the luxR expression with AHL-independent manner. ∙LuxR-AHL affects the luxR mRNA stability by regulating the expression of hfq encoding RNA chaperone. [ABSTRACT FROM AUTHOR]

Algorithm is a step of problem-solving, and algorithm can be defined as any special method for solving a certain type of problem. In computer science, algorithms are described in computer algorithm language and represent accurate and effective methods for solving a class of problems with computers. In order to verify the role of the OTO teaching mode from the perspective of cultivating learning interest and to provide a practical basis for the reform of physical education in colleges and universities, 107 second-year physical education majors in a common university were selected as experimental subjects and divided into an experimental group and a control group, and the two groups were intervened through a 16-week experiment. Multivariate covariance was used to analyze the influence of two teaching modes on college students' interest in sports learning. After excluding factors such as student gender, physical exercise behavior stage, football learning experience, and physical health, the groups have statistical significance in the four dimensions of positivity, skill learning, extracurricular activities, and negativity in sports learning interest. However, there is no significant difference in the influence of sports attention on sports learning interest. The research proves that the application of OTO teaching mode is conducive to promoting students' learning positivity, technical learning, and extracurricular activities and alleviating students' negative learning emotions. The degree of attention to sports in the interest of sports learning is not very significant. It is suggested that colleges and universities adopt the OTO teaching mode in the teaching of general football courses. [ABSTRACT FROM AUTHOR]