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SiC@SiO 2 nanofiber material holds great potential for a wide range of applications in microelectronic devices and electromagnetic wave absorption. However, its development has been hindered by high energy consumption (＞1500 °C) and complex fabrication methods. This work introduces a sample approach to produce the SiC@SiO 2 nanofiber at temperature of ∼1000 °C by using microwave heating. The SiC@SiO 2 nanofiber possess a unique bead-like structure, which are composed of single-crystalline SiC nanowires and amorphous SiO 2 beads. The growth mechanism under the action of microwave was explained. Moreover, the SiC@SiO 2 nanofiber exhibits an Excellent electromagnetic wave absorption performance with a minimum refection loss (RL min) value of −36.54 dB. The successful preparation of SiC@SiO 2 nanofiber provides a new idea for preparing ceramic materials with low cost and high efficiency in the future. [ABSTRACT FROM AUTHOR]

In recent years, the rapid development of exoplanet research has provided us with an opportunity to better understand planetary systems in the universe and to search for signs of life. In order to further investigate the prevalence of habitable exoplanets and to validate planetary formation theories, as well as to comprehend planetary evolution, we have utilized confirmed exoplanet data obtained from the NASA Exoplanet Archive database, including data released by telescopes such as Kepler and TESS. By analyzing these data, we have selected a sample of planets around F, G, K, and M-type stars within a radius range of 1 to 20 R ⊕ and with orbital periods ranging from 0.4 days to 400 days. Using the IDEM method based on these data, we calculated the overall formation rate, which is estimated to be 2.02%. Then, we use these data to analyze the relationship among planet formation rates, stellar metallicity, and stellar gravitational acceleration ( log g ). We firstly find that the formation rate of giant planets is higher around metal-rich stellars, but it inhibits the formation of gas giants when log g > 4.5, yet the stellar metallicity seems to have no effect on the formation rate of smaller planets. Secondly, the host stellar gravitational acceleration affects the relationship between planet formation rate and orbital period. Thirdly, there is a robust power-law relationship between the orbital period of smaller planets and their formation rate. Finally, we find that, for a given orbital period, there is a positive correlation between the planet formation rate and the log g . [ABSTRACT FROM AUTHOR]

The laminar burning velocity of n-decane (an aviation kerosene surrogate) blended with hydrogen is studied using experimental and numerical analysis at the initial conditions of 470 K and 1, 2, and 4 bar over the equivalence ratios of 0.7–1.3 and hydrogen addition ratios of 0 %, 10 %, 20 %, 30 %, 40 %, and 50 %. The burning velocity is investigated using the constant volume method of the spherically expanding flame method. Here, burning velocity at elevated pressure and temperature conditions close to engine-relevant conditions have been established. Thus, using the experimental data at 470 K and 4 bar, burning velocities at the unburnt temperatures of up to 612 K and pressures of up to 11.02 bar are obtained. Also, Polimi and JetSurF2.0 mechanisms were used to simulate the burning velocities and they agreed well with the experimental data. However, as the hydrogen addition increased, especially when the hydrogen addition was 40 % there was a significant deviation between the experiment and the simulation results. The chemical reaction analysis of n-decane-hydrogen shows the flame speed is significantly driven by H + O 2 ⇔ O + OH , CO + OH ⇔ CO 2 + H , CH 3 + H (+ M) ⇔ C H 4 (+ M) , and H + OH + M ⇔ H 2 O + M at the various initial conditions. However, H + O 2 ⇔ O + OH produces more OH, H, and O radicals that accelerate the combustion chemical reaction rate of n-decane-hydrogen. The reaction pathways show that the decomposition of n-decane is mainly controlled by the OH and H radicals. This study's results provide an understanding of the combustion characteristics of aviation fuel-hydrogen blends in internal combustion engines at elevated pressures and temperatures to achieve zero emissions in aviation. • Laminar combustion characteristics of n-decane-hydrogen were studied. • Burning velocity at 11.02 bar and 612 K were obtained for n-decane-hydrogen. • H + O 2 ⇔ O + OH , CH 3 + H (+ M) ⇔ C H 4 (+ M) , and H + OH + M ⇔ H 2 O + M drove the flame speed. • OH, H and O radicals enhanced the combustion reactivity of n-decane-hydrogen. [ABSTRACT FROM AUTHOR]

The cellularization and intrinsic instability of ethyl acetate (EA) spherical expanding flame with different proportions of hydrogen (4%, 8%, 12%) were studied through experiments and theoretical analysis. The high-speed schlieren imaging technique combined with the image processing method was used in the constant volume combustion chamber to quantify the development of flame surface cracks and saturation time, crack length, number of cellular units, and average cellular area. The results show that the evolution of flame cracks can be mainly classified into two periods. In the first period, several initial cracks are generated on the flame surface. In the second period, cracks rapidly expand while forming a large number of small cellular units, and the surface areas also increase rapidly. The increase in the proportion of hydrogen led to an increase in minor cellular cracks and a more moderate structural evolution of flame cells during the second period. Afterwards, the involved thermodynamic parameters, including the thermal expansion ratio, flame thickness, effective Lewis number, critical Peclet number, and perturbation logarithmic growth rate of unstable flames, were quantitatively analyzed. The results show that an increase in initial pressure significantly reduces the flame thickness, leading to more unstable flame. In contrast, the proportion of hydrogen has less impact on the involved thermodynamic parameters, while the equivalence ratio is the primary factor influencing instability parameters. Additionally, the study examined the flame's self-acceleration characteristics and found that increasing the proportion of hydrogen reduces the tendency for ethyl acetate self-acceleration. • Investigated cellularization characteristics of ethyl acetate (EA) with hydrogen addition. • Investigated theoretical instability of EA with hydrogen addition. • Investigated four instability parameters of EA with hydrogen addition. • Investigated self-accelerating characteristics of EA with hydrogen addition. [ABSTRACT FROM AUTHOR]

Background: Rhodococci are studied for their bacterial ligninolytic capabilities and proclivity to accumulate lipids. Lignin utilization is a resource intensive process requiring a variety of redox active enzymes and cofactors for degradation as well as defense against the resulting toxic byproducts and oxidative conditions. Studying enzyme expression and regulation between carbon sources will help decode the metabolic rewiring that stymies lignin to lipid conversion in these bacteria. Herein, a redox proteomics approach was applied to investigate a fundamental driver of carbon catabolism and lipid anabolism: redox balance. Results: A consortium of Rhodococcus strains was employed in this study given its higher capacity for lignin degradation compared to monocultures. This consortium was grown on glucose vs. lignin under nitrogen limitation to study the importance of redox balance as it relates to nutrient availability. A modified bottom–up proteomics workflow was harnessed to acquire a general relationship between protein abundance and protein redox states. Global proteomics results affirm differential expression of enzymes involved in sugar metabolism vs. those involved in lignin degradation and aromatics metabolism. As reported previously, several enzymes in the lipid biosynthetic pathways were downregulated, whereas many involved in β-oxidation were upregulated. Interestingly, proteins involved in oxidative stress response were also upregulated perhaps in response to lignin degradation and aromatics catabolism, which require oxygen and reactive oxygen species and generate toxic byproducts. Enzymes displaying little-to-no change in abundance but differences in redox state were observed in various pathways for carbon utilization (e.g., β‑ketoadipate pathway), lipid metabolism, as well as nitrogen metabolism (e.g., purine scavenging/synthesis), suggesting potential mechanisms of redox-dependent regulation of metabolism. Conclusions: Efficient lipid production requires a steady carbon and energy flux while balancing fundamental requirements for enzyme production and cell maintenance. For lignin, we theorize that this balance is difficult to establish due to resource expenditure for enzyme production and stress response. This is supported by significant changes to protein abundances and protein cysteine oxidation in various metabolic pathways and redox processes. [ABSTRACT FROM AUTHOR]

Information on survival and growth during the early life stage is essential to understand the mechanism of interannual variations in fish recruitment. Chub mackerel Scomber japonicus is a commercially important pelagic fish widely distributed in the northwestern Pacific. Its catch showed large fluctuations with changes in distribution and migration under climate change and strong fishing. We determined the hatch dates and growth rates of young-of-the-year of chub mackerel through otolith microstructure using samples collected in the Oyashio water in autumn 2018. Results show that the ages of young chub mackerel ranged between 120 and 180 d, and the estimated hatch date lasted from mid-January to late May with a peak from mid-March to mid-April. Average otolith daily increment width during the early life stages (from hatching to 25 d) showed an increasing trend. Chub mackerel grows slowly in the first 10 d, and then grows faster during the 10th to 25th d. Three groups with dissimilar growth histories and migration routes were identified using unsupervised random forest clustering analysis, but all eventually converge on the same nursery ground. The faster growth of young-of-the-year chub mackerel leads to better recruitment due to the hypothesis of growth-dependent mortality. Most chub mackerels hatched in March and April, the spawning period is longer and earlier, which could lead to strong year classes. These findings on population composition and life history traits of young-of-the-year of chub mackerel provide valuable information on its recruitment processes during the period of stock recovery. [ABSTRACT FROM AUTHOR]

Time-frequency analysis is recognized as a dynamic tool to analyze the nonstationary signal. The synchrosqueezing transform is usually applied as a post-processing method to further improve the readability of the time-frequency representation. Synchrosqueezing transform is related to the reassignment method and can be performed in two directions, namely time direction and frequency direction. Frequency-direction reassignment helps to squeeze the slowly changing ridge. However, the time-direction reassignment is efficient to process the signal with rapid variation in instantaneous frequency. Thus, there exists a conflict in most of the time-frequency analysis methods while dealing with a signal containing both of these two components. In this study, a new method called demodulated time-direction synchrosqueezing transform is introduced, which is not only capable of achieving a higher compact TFR but also allow reconstructing the mode. In order to explain demodulated time-direction synchrosqueezing transform, a signal model is established in frequency domain. Then, a demodulated procedure is implemented to eliminate time-frequency analysis diffusion. Finally, time-direction reassignment is carried out to further enhance the energy concentration of the time-frequency analysis. The proposed demodulated time-direction synchrosqueezing transform method is evaluated by both simulation and experimental research. The results reveal that the performance of demodulated time-direction synchrosqueezing transform is better than the conventional time-frequency analysis methods, and it can be applied to the fault diagnosis in a machine. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the correlation between histogram parameters derived from synthetic magnetic resonance imaging (SyMRI) and prognostically relevant factors in nasopharyngeal carcinoma (NPC). Methods: Fifty-nine consecutive NPC patients were prospectively enrolled. Quantitative parameters (T1, T2, and proton density (PD)) were obtained by outlining the three-dimensional volume of interest (VOI) of all lesions. Then, histogram analysis of these quantitative parameters was performed and the correlations with prognostically relevant factors were assessed. By choosing appropriate cutoff, we divided the sample into two groups. Independent-samples t test/Mann–Whitney U test was used and ROC curve analysis was further processed. Results: Histogram parameters of the T1, T2, and PD maps were positively correlated with the Ki-67 expression levels, and PD_mean was the most representative parameter (AUC: 0.861). The PD map exhibited good performance in differentiating epidermal growth factor receptor (EGFR) expression levels (AUC: 0.706~0.732) and histological type (AUC: 0.650~0.660). T2_minimum was highest correlated with Epstein-Barr virus (EBV) DNA levels (r = − 0.419), and PD_75th percentile exhibited the highest performance in distinguishing positive and negative EBV DNA groups (AUC: 0.721). T1_minimum was statistically correlated with EA-IgA expression (r = − 0.313). Additionally, several histogram parameters were negatively correlated with tumor stage (T stage: r = − 0.259 ~ − 0.301; N stage: r = − 0.348 ~ − 0.456; clinical stage: r = − 0.419). Conclusions: Histogram parameters of SyMRI could reflect tissue intrinsic characteristics and showed potential value in assessing the Ki-67 and EGFR expression levels, histological type, EBV DNA level, EA-IgA, and tumor stage. Key Points: • SyMRI combined with histogram analysis may help clinicians to assess different prognostic factor statuses in nasopharyngeal carcinoma. • The PD map exhibited good discriminating performance in the Ki-67 and EGFR expression levels. • Histogram parameters of SyMRI were negatively correlated with EBV-related blood biomarkers and TNM stage. [ABSTRACT FROM AUTHOR]

Plant phenology regulates the carbon cycle and land‐atmosphere coupling. Currently, climate models often disagree with observations on the seasonal cycle of vegetation growth, partially due to how spring onset is measured and simulated. Here we use both thermal and leaf area index (LAI) based indicators to characterize spring onset in CMIP6 models. Although the historical timing varies considerably across models, most agree that spring has advanced in recent decades and will continue to arrive earlier with future warming. Across the Northern Hemisphere for the periods 1950–2014, 1981–2014, and 2015–2099 in the historical and SSP5‐8.5 simulations, thermal‐based indicators estimate spring advances of −0.7 ± 0.2, −1.4 ± 0.4, and −2.4 ± 0.7 days/decade, while LAI‐based indicators estimate −0.4 ± 0.3, −0.1 ± 0.3, and −1±1.1 days/decade. Thereby, LAI‐based indicators exhibit weaker trends toward earlier onset, leading to uncertainties from different indices being as large or larger than model uncertainty. Reconciling these discrepancies is critical for understanding future changes in spring onset. Plain Language Summary: The timing of spring onset as indicated by green‐up affects plants, bird and insect populations, rivers, and agriculture. However, state‐of‐the‐art land surface models disagree with satellite‐derived records on the seasonal cycles of vegetation growth, making it difficult to accurately predict green‐up, its response to climate, and the ecological consequences. Here we calculate two sets of spring onset indicators using climate model outputs to characterize spring onset variations and trends in the recent past and future. We find spring has been advancing in recent decades and will continue to arrive earlier with future warming. Thermal‐based indicators show that spring onset advances by −0.7, −1.4, and −2.4 days/decade in the Northern Hemisphere during 1950–2014, 1981–2014, and 2015–2099, respectively. This result suggests that spring onset today is on average four days earlier than spring onset 30 years ago and this rate will nearly double in the future. However, compared to meteorological‐based indicators, vegetation growth‐based indicators exhibit weaker trends toward earlier onset. Therefore, how we define and measure spring onset, as well as the models we use to predict changes in the environmental factors, influence future changes in the start of spring. Key Points: Divergence between thermal‐ and growth‐based spring onset indicators grows with time as global temperatures increaseThermal‐based indicators estimate spring advances of −0.7, −1.4, and −2.4 days/decade in 1950–2014, 1981–2014, and 2015–2099Vegetation growth‐based indicators exhibit weaker trends toward earlier spring onset and larger disagreements among models [ABSTRACT FROM AUTHOR]

The mechanical properties of sandy soil depend on both the confining pressure and the state of compactness. Therefore, both the buried depth of the tunnel and the relative density of the sand are key factors that affect the ground deformation induced by the tunneling of a super-large-diameter shield. In this study, the parameters of the SANISAND constitutive model are first calibrated based on triaxial test data for Foshan silty fine sand. Then, based on the actual project, a two-dimensional finite-element analysis model is established to investigate the ground deformation induced by the tunneling of a super-large-diameter shield. The width and maximum value of the settlement trough, the volume loss ratio, and the deformation characteristics of the soil are summarized and analyzed for 13 cases. The results show that as the ratio of the buried depth to the diameter and the relative density of sand increases, the anti-disturbance ability of the sand layer to the tunnel construction increases and the volume loss ratio of the stratum reduces correspondingly. The denser the sand and the smaller the confining pressure of the soil around the tunnel, the more significant the shear-induced expansion of the sand at the tunnel haunch; this expansion partially makes up the volume loss caused by the tunnel excavation and reduces the loss ratio of the stratum at the arch crown. [ABSTRACT FROM AUTHOR]

Highlights: Thermosensitive fire alarms with various working mechanisms are overviewed. Different calculation methods for response time are discussed. Warning signal conversion types are provided. Limitations, challenges, and development direction are put forward. Early-stage fire-warning systems (EFWSs) have attracted significant attention owing to their superiority in detecting fire situations occurring in the pre-combustion process. Substantial progress on EFWSs has been achieved recently, and they have presented a considerable possibility for more evacuation time to control constant unintentional fire hazards in our daily life. This review mainly makes a comprehensive summary of the current EFWSs, including the working mechanisms and their performance. According to the different working mechanisms, fire alarms can be classified into graphene oxide-based fire alarms, semiconductor-based fire alarms, thermoelectric-based fire alarms, and fire alarms on other working mechanisms. Finally, the challenge and prospect for EFWSs are briefly provided by comparing the art of state of fire alarms. This work can propose a more comprehensive understanding of EFWSs and a guideline for the cutting-edge development direction of EFWSs for readers. [ABSTRACT FROM AUTHOR]

The Joule heating behavior of the carbon fiber/epoxy composite (CF/EP) was studied in this work, as well as their influence on the in-situ mechanical properties of the composites and their de-icing performance. The equilibrium temperature of the CF/EP composite could be conveniently adjusted by tuning the current according to the Joule's law. Dynamic mechanical analysis (DMA) tests indicated that the rigidity and stiffness of the fiber-reinforced composite decreased with increasing temperature, and the glass transition temperature (Tg) of the composites was around 104 °C. It was found that the flexural properties of the composites in situ, measured under the electric-current loading, depended on the current value in the range of room temperature to Tg. With increasing the loading current, either the flexural modulus or strength of CF/EP decreased gradually. Such results could be explained that the higher current loading, the larger Joule heat, led to the higher operating temperature of the composite samples and the evolution of their mechanical properties accordingly. Vickers hardness tests indicated that the micro-hardness of the composite decreased with the increase of the operating temperature, which coincided with the evolution of its flexural properties with the electric-current loading. The dependence of the failure behaviors of the CF/EP on the loading current was revealed by the analysis of their fractured surface, where micro-buckling, kinking, fiber pull-out and breakage were involved. A preliminary study indicated that less energy was consumed for the deicing of the same amount of the ice with the CF/EP composite in the case of less electric-current loading. The research on the Joule heating effect of CF/EP and their corresponding mechanical properties benefits the design and direct application of the composites under the electric-current loading. [ABSTRACT FROM AUTHOR]

Highlights: Thermosensitive fire alarms with various working mechanisms are overviewed. Different calculation methods for response time are discussed. Warning signal conversion types are provided. Limitations, challenges, and development direction are put forward. Early-stage fire-warning systems (EFWSs) have attracted significant attention owing to their superiority in detecting fire situations occurring in the pre-combustion process. Substantial progress on EFWSs has been achieved recently, and they have presented a considerable possibility for more evacuation time to control constant unintentional fire hazards in our daily life. This review mainly makes a comprehensive summary of the current EFWSs, including the working mechanisms and their performance. According to the different working mechanisms, fire alarms can be classified into graphene oxide-based fire alarms, semiconductor-based fire alarms, thermoelectric-based fire alarms, and fire alarms on other working mechanisms. Finally, the challenge and prospect for EFWSs are briefly provided by comparing the art of state of fire alarms. This work can propose a more comprehensive understanding of EFWSs and a guideline for the cutting-edge development direction of EFWSs for readers. [ABSTRACT FROM AUTHOR]

In this work, the effect of a hydrothermal environment on mechanical properties and the electrical response behavior of continuous carbon fiber/epoxy (CFRE) composite produced by the pultrusion method were investigated. Due to the relatively uniform distribution of fibers and lack of resin-rich interlayer area, this effect for the pultruded CFRE composite plates is different from the common CFRE laminated composites. Firstly, its hygroscopicity behavior was studied. The absorption ratio increases rapidly to 1.02% within 3 days before reaching a relatively stable state. A three-point bending test, a Vickers hardness test, a thermogravimetric analysis (TGA), and a scanning electron microscope (SEM) analysis were performed to investigate the effect of the hydrothermal environment on the mechanical properties and thermal stability of the CFRE composite. The results indicated that the bending strength decreased quickly within 3 days of hydrothermal treatment, followed by a stable trend, which coincided with that of the hygroscopicity behavior of the composites. The fracture surface analysis indicated that the interfacial properties of carbon fibers in the epoxy matrix were decreased after the hydrothermal treatment, and more carbon fibers could be pulled out from the CFRE in the hygroscopic state. After the hydrothermal treatment, the micro-hardness of the composites was reduced by 25%. TGA confirmed the decreased thermal stability of the CFRE composites after the hydrothermal treatment as well. Moreover, the hydrothermally treated CFRE composites could a reach stable resistance response more readily. The revealing of the effect of moisture and hot environment on the mechanical properties and electrical response behavior of pultruded CFRE composites prepares the ground for their design and practical application in the corresponding environment. [ABSTRACT FROM AUTHOR]

This article addresses the design of reconfigurable single-inductor multiport converters with bidirectional power flow, no cross regulation, and simple control. The design uses both the voltage-source-mode and current-source-mode cells, thus allowing a full range of connectivity. The proposed single-inductor converters offer high modularity and scalability while offering bidirectional power flow and no cross regulation. The single-inductor structure reduces the overall size. The adoption of voltage-source-mode and current-source-mode cells leads to high modularity. High scalability is achieved due to arbitrary ports being allowed to the derived converters. Moreover, the topology inherently achieves no cross regulation among the output ports. The ports of the derived converters are reconfigurable, permitting transformation among single-input multi-output mode, multi-input multi-output mode, and multi-input single-output mode. Through the transformation of operating modes, bidirectional power flow is achieved. Thus, regenerative loads can be integrated seamlessly. In terms of control, the absence of cross regulation permits the adoption of very simple control design, leading to high flexibility. Thus, the derived converters can integrate multiple and various kinds of terminating sources and loads simultaneously with simple control methods. A reconfigurable single-inductor four-port converter is presented for illustration. Finally, experimental results are presented to verify the analytical findings. [ABSTRACT FROM AUTHOR]

• A comprehensive model is established to predict the noise distribution, combing analytical formulations with the Monte Carlo method to improve the computational efficiency while ensuring the accuracy. • An analytical method is developed based on kernel regression to transform simulation data pairs into probability density function, linking the theoretical and measured data. Based on that, two statistical indicators (E d and L d) are proposed to evaluate the noise characteristics for model validation. • Adjustable and controllable indoor laboratory tests are conducted to validate the model in rain and fog conditions. The relative errors of E d and L d between the proposed model and measurements are below 6%, outperforming the contrasting methods. Rain-and-fog-induced noises deteriorate the imaging capability of LiDAR applied for autonomous driving. To explore the noise generation mechanism, a comprehensive model considering the LiDAR systematic attributes and environmental characteristics is established for predicting the noise distribution probability based on the photon motion simulation. The analytical formulations are innovatively combined with the Monte Carlo method to enhance the computational efficiency while ensuring accuracy, by utilizing a kernel regression method to link the theoretical model with practical measurements. Experiments are conducted via computer simulation and a serial of adjustable fog-and-rain laboratory simulation tests, with two novel statistical indicators proposed for model validation. The experimental results show that the maximum relative error between the model and measurements is less than 6%, outperforming the contrasting methods. The presented model and results can provide insights for reducing aerosol particle noise and evaluating LiDAR imaging in adverse weathers. [ABSTRACT FROM AUTHOR]

• A variable substitution-based Gauss-Newton ranging method is proposed for high-accuracy full-waveform LiDAR. • An innovative module-level pipeline implemented on FPGA is designed for high-measurement-rate laser ranging. • The module-and-operation acceleration mechanism is elaborated to provide a theoretical base for pipeline design. • Experimental results demonstrate the maximum ranging measurement rate achieves megahertz. With laser repetition frequency increasing from kilohertz to megahertz, the full-waveform LiDAR requires fast recording and online processing massive echo waveforms for real-timely accurate ranging. To address the time consuming issue of multiple sequential iterations, a module-level pipeline structure based Gauss-Newton online ranging method is advanced and implemented on FPGA (ZYNQ-7000). Each iteration of Gauss-Newton ranging is divided into three functional modules and each functional module is further optimized by an operation-level parallel-pipeline design to increase the ranging measurement rate up to 1.90 MHz. The online ranging experiments were carried out in National Institute of Metrology of China and Beihang LiDAR Lab, which showed the ranging standard deviation (RStD) achieves 1.9 mm@52.40 dB and 21.6 mm@16.93 dB; the absolute of mean ranging error (MRE) is lower than 1.1 mm@16.93 dB. The online ranging method offers an effective solution to real-timely generate high-quality and high-density three-dimensional images. [ABSTRACT FROM AUTHOR]

Large-scale changes in the state of the land surface affect the circulation of the atmosphere and the structure and function of ecosystems alike. As global temperatures increase and regional climates change, the timing of key plant phenophase changes are likely to shift as well. Here we evaluate a suite of phenometrics designed to facilitate an "apples to apples" comparison between remote sensing products and climate model output. Specifically, we derive day-of-year (DOY) thresholds of leaf area index (LAI) from both remote sensing and the Community Land Model (CLM) over the Northern Hemisphere. This systematic approach to comparing phenologically relevant variables reveals appreciable differences in both LAI seasonal cycle and spring onset timing between model simulated phenology and satellite records. For example, phenological spring onset in the model occurs on average 30 days later than observed, especially for evergreen plant functional types. The disagreement in phenology can result in a mean bias of approximately 5% of the total estimated Northern Hemisphere NPP. Further, while the more recent version of CLM (v5.0) exhibits seasonal mean LAI values that are in closer agreement with satellite data than its predecessor (CLM4.5), LAI seasonal cycles in CLM5.0 exhibit poorer agreement. Therefore, despite broad improvements for a range of states and fluxes from CLM4.5 to CLM5.0, degradation of plant phenology occurs in CLM5.0. Therefore, any coupling between the land surface and the atmosphere that depends on vegetation state might not be fully captured by the existing generation of the model. We also discuss several avenues for improving the fidelity between observations and model simulations. [ABSTRACT FROM AUTHOR]

• MPe maximum rate of pressure rise was insensitive to the initial temperature. • MPe experimental and adiabatic deflagration indices showed satisfactory agreement. • MPe explosions were hazardous at high pressures and in rich mixtures. • MPe unstable flame crack lengths and cell numbers were more sensitive to pressure. Combustible fuels like methyl pentanoate (MPe) could cause accidental explosions and fire. Therefore, MPe explosion characteristics have to be well characterized and understood for its safe and reliable use in industries and combustion devices. Considering this, MPe's explosion pressure, maximum explosion pressure, rate of pressure rise, maximum rate of pressure rise, heat release rate, etc., were investigated in this study at the initial conditions of 1, 2, and 4 bar and 423 K, 453 K, and 483 K using the equivalence ratios of 0.7–1.4. The maximum explosion pressures and maximum rate of pressure rise of MPe increased as the initial pressures increased but the maximum rate of pressure rise was insignificantly affected by the initial temperature. The explosion duration decreased with a decrease in the initial pressure. The maximum heat release rate and deflagration index increased with increasing initial pressure. The MPe maximum deflagration index was 224.8 bar•m/s, which occurred at a higher initial pressure and fuel-rich mixture. Therefore, the explosion severity of MPe was enhanced at higher initial pressures and fuel-rich mixtures. Moreover, the flame cellularity study showed that MPe unstable flame crack length and cell number were more affected by increments in the initial pressure and equivalence ratio. Therefore, flame instability and cellularity would significantly influence explosion severity at higher pressures and equivalence ratios. This study's findings provide first-hand data that could be used to further investigate and characterize MPe's explosion risk. [ABSTRACT FROM AUTHOR]

• A novel line feature based self-calibration method is proposed for dual-axis scanning LiDAR, providing a convenient way to correct point-cloud error of environmental perception LiDAR. • Self-calibration of LiDAR is achieved without the usage of high-precision instrument, by modeling the point-cloud error relative to the line features and estimating the model parameters. • Explicit analysis on correlation among model parameters is conducted, enabling a reasonable strategy for the de-correlation of model parameters. • A series of solid experiments are conducted to verify the feasibility of self-calibration using line features, expanding research view of LiDAR calibration technology. LiDAR calibration is an essential step for acquiring accurate three-dimensional point-cloud. To enhance the convenience of calibration of dual-axis scanning LiDAR, a line feature based self-calibration method is proposed, which corrects point-cloud error by establishing observation model and estimating model parameters. The model parameters are estimated by minimizing the square error of line feature points, referring as straight edges extracted from point-cloud. The experimental results verify the effectiveness of the proposed method on improving point-cloud accuracy, the horizontal and vertical angular errors are reduced to 0.10° and 0.08° after calibration with reductions of 64% and 68%, respectively. The analysis on parameter correlation finds that, parameters can be divided into groups according to the introduced point-cloud error: dimension error, trapezoid and parallelogram shape distortion. A de-correlation strategy combining inter-group and stepwise intra-group de-correlation thus can be implemented, which can be applied for point-cloud quality enhancement in in-situ environmental perception scenes. [ABSTRACT FROM AUTHOR]

Recent advances separately in edge intelligence, service-centric networking, and software-defined networking have profoundly impacted future networks and intelligent applications. Nevertheless, they have not been jointly considered. Jointly considering these three remarkable techniques will open up a nascent research direction. In this article, we propose a software-defined service-centric networking (SDSCN) framework to push the frontier of edge intelligence toward general in-network intelligence. We devise a three-plane architecture, including a data plane, a management plane, and a control plane. Specifically, in-network context-aware computing and caching capabilities are incorporated into the service-centric data plane. Network programmability and global orchestration provide the potential to design plenty of useful network applications to customize network behaviors flexibly. How in-network federated learning works in SDSCN can be observed from case studies and is validated by emulation. More simulation results show the outperformance of SDSCN. Several challenges in developing the proposed framework are presented and discussed. [ABSTRACT FROM AUTHOR]

Light detection and ranging (LiDAR) provides a 3-D understanding of environment and plays an important role in autonomous driving. To study the influence of 3-D data quality on the environment perception and provide a theoretical basis for optimizing system design, a multi-beam LiDAR perception assessment model has been established to reveal the relationship between data quality and multi-parameters, including system and motion parameters. A novel ground segmentation algorithm was proposed with a combination of the grid elevation and the neighbor relationship, which was used to validate how the data quality influences the results of environment perception. By the way of down-sampling based on the Karlsruhe Institute of Technology and Toyota Technological Institute (KITTI) dataset, the experimental results showed that the proposed ground segmentation with combination of grid-elevation and neighbor-relationship (GSCGN) method was superior than other general ground segmentation methods in terms of accuracy and efficiency. It should be noted that the mean vertical angular resolution (MVAR), laser repetition frequency, and beam numbers were the dominant influencing parameters on the point density and the accuracy of ground segmentation. Based on the experimental results, the lower limits of system parameters were determined as 16-beam and 4-kHz repetition frequency, with the acceptable recall of 92.2% for ground and 93.5% for object, the accuracy of 92.9% and the runtime of 0.036 s, which can not only provide a reliable environment perception effect, but also reducing the computational burden to satisfy the real-time autonomous driving. This study offers a meaningful investigation to guide LiDAR system design with balancing the contradiction between the optimized system design and the high-degree environment perception. [ABSTRACT FROM AUTHOR]

Early fire detection is an efficient method to mitigate disastrous fire loss. However, developing smart low-temperature fire-warning sensors that better diminish fire hazards, especially those caused by household appliances, is still challenging. Herein, a salts-modified chitosan (salts-modified CS) based sensor with integrated fire-warning and humidity-monitoring capability is proposed using an easy assembling method. This sensor can respond to temperatures as low as 50 °C and a flame within 2 s quickly and detect relative humidity (RH) range above 50 % at 50 °C and 75 °C sensitively. This system can be reusable for multiple ignitions and works in high-humidity environments (>50 %). Furthermore, the comparison between different salts-modified CS films is carried out to elucidate the mechanism of the formation of electric current under the joint driven by temperature and humidity. Moreover, real-time temperature and RH monitoring can be achieved with a wireless transmission section. This design shows a promising approach for multifunctional CS-based sensors and paves a path to developing a new generation of smart fire-warning detectors. [Display omitted] • The functional chitosan-based film is used as a fire-warning and humidity sensor. • The sensor responds to a low temperature of 50 °C and a high-humidity environment. • This sensor presents reusable fire warnings under multiple fire attacks. • The real-time message of temperature and humidity is transmitted via wireless. [ABSTRACT FROM AUTHOR]

• A novel neighbor feature variance (NFV) based feature points selection method is proposed to provide the high precision input of point clouds based registration and promote the pose estimation accuracy of space targets. • When the point noise standard is twice the point resolution, the maximum translation error and maximum rotation error for registration are less than 0.019 m and 0.129°. Compared with the registration without the proposed feature point selection method, the mean translation and rotation errors can be reduced by 69.85% and 60.58%, respectively. • The NFV based feature point selection method for 3D registration is capable to address the challenges of variable scale and high noise points based registration. Point clouds based three dimensional (3D) registration for the space target pose estimation requires high precision and noise robustness. To enhance the registration accuracy, a novel neighbor feature variance (NFV) based feature points selection method is proposed to provide the high precision input of point clouds based registration and promote the pose estimation accuracy of space targets. The proposed method generates more accurate correspondences by selecting the rank of all point's NFV, for removing the redundant points and remaining more salient points for accurate registration. In coarse registration, the truncated least squares estimation and semidefinite relaxation (TEASER) algorithm is used to improve the accuracy of coarse registration and reduce the adverse effects caused by sparsity and noise of point cloud. In fine registration, the iterative closest point (ICP) algorithm is applied to estimate the pose transformation. The experimental results show that the maximum translation error and maximum rotation error are less than 0.019 m and 0.129°, and the mean translation and rotation errors can be reduced by 69.85% and 60.58%, respectively. Compared to the registration without the optimization algorithm, the proposed method can be used for variable scale and high noise points based registration. [ABSTRACT FROM AUTHOR]

Nitrogen-doped graphene (NG) was synthesized via direct thermal annealing treatment. The obtained NG showed outstanding removal ability for tetracycline (TC) ascribed to enhanced adsorption and persulfate activation. The maximum TC adsorption capacity calculated from the Langmuir model of NG was 227.3 mg/g, which was 1.66 times larger than nitrogen-free graphene. The coexistence of NG and persulfate (PS) exhibited complete degradation of TC within 120 min attributed to the successful modification of nitrogen. Further analysis demonstrated that non-radical electron transfer was the dominant degradation pathway, which was different from the widely acknowledgeable radical mechanism. An electron donor-mediator-acceptor system was introduced, in which TC, NG, and PS performed as electron donor, mediator, and acceptor, respectively. The potential intermediates in the TC degradation process were detected and toxicity assessment was also performed. In addition, more than 75.8% of total organic carbon was removed, and excellent reusability was manifested in multiple adsorption and degradation experiments. [Display omitted] • Nitrogen-doped graphene (NG) benefitted adsorption and catalytic degradation of TC. • Increased pore volume, π-π EDA and Lewis-based interaction promoted TC adsorption. • The NG/PS system for TC degradation was a nonradical oxidation process. • An electron donor-mediator-acceptor system was introduced. • The degradation process of TC and toxicity assessment were proposed. [ABSTRACT FROM AUTHOR]

Due to its location in a politically and militarily sensitive area as a maritime demarcation between North and South Korea, increasing attention has been given to the chemical and physical changes in atmospheric aerosols on Baengnyeong Island. To observe modifications in the concentrations and components of basic air pollutants, a Korean State Air Quality Monitoring Superstation was established on the island. The monitoring data obtained from the superstation revealed a significant, short-lived increase in mass concentration of SO 2 , NO 2 , and nitrate, organic carbon, and heavy metals (especially Pb) in ambient PM 2.5 , as well as a gradual decrease in mass concentration of PM 10 , PM 2.5 , and sulfate in PM 2.5 during September 24–27, 2012. Building upon this data, we conducted source appointment of PM 2.5 using the positive matrix factorization receptor model (PMF) and identified six major sources: sea-spray aerosols (29.8%), mobile and biogenic aerosols (24.3%), secondary aerosols (20.0%), gunshot residue (11.1%), mineral dust (8.6%), and oil combustion (6.3%). To examine the physicochemical properties of atmospheric particles, 16 samples collected during that period were investigated using a quantitative energy-dispersive electron probe X-ray microanalysis (ED-EPMA). We analyzed the morphology, mixing state, elemental constituents, and relative elemental atomic concentrations of 2545 individual particles from the aforementioned six sources, with a focus on particles containing Ca, organic carbon, and Pb. The complementary use of PMF and ED-EPMA confirmed that an episode of air pollution, likely resulting from a military exercise or activity, occurred from September 25 to 26 on or near Baengnyeong Island, leading to an increase in aerosols from gunshot residue and oil combustion. The significant increase in the relative number abundance of organic carbon and heavy metal-containing particles precisely matched their mass concentrations from the monitoring data. These findings imply that multiple methods for bulk and single-particle analysis are necessary when addressing important issues related to source appointment of atmospheric particulate matter. • An episodic increase in organic carbon and heavy metal-containing fine particles was observed on Baengnyeong Island. • The ion ratios of NO 3 −/SO 4 2− and NH 4 +/SO 4 2− experienced a noteworthy rise concurrently with elevation of organic carbon. • Ambient fine particles likely from gunshot residue and oil combustion on Baengnyeong Island were identified. • Quantitative ED-EPMA could be well complementary to PMF analysis for source appointment of atmospheric particles. [ABSTRACT FROM AUTHOR]

Multi-input multi-output (MIMO) dc–dc converters can integrate multiple input sources and output loads simultaneously. This article proposes a new single-inductor MIMO dc–dc converter with a wide conversion ratio. The proposed converter allows input sources to be added or removed seamlessly with no cross-regulation problem. Meanwhile, the outputs are independently controlled, i.e., the load change at one output cell will not affect the other interconnected output cells. Constant current control is the main control requirement. When constant current control is applied to all input cells, the power provided by each input source is proportional to the voltage magnitude of the source. When the constant current control is applied to some of the input cells, the input sources with direct duty-cycle controlled input cells can provide specific power through controlling the duty cycles of the switches of the corresponding input cells. Moreover, the switching time of switches is irrelevant. Therefore, it is easy to realize the high extension capability for arbitrary inputs/outputs. A dual-input dual-output prototype is constructed to illustrate the performance of the proposed converter. The corresponding component design is presented. [ABSTRACT FROM AUTHOR]

The design of power converter circuits is highly dependent on the types of the input and output terminations. Conventional dc–dc converters assume the input termination being a voltage source, and the converter circuits so developed are voltage-source-mode (VSM) converters which generally consist in switching an inductor between the input and the output with two complementary switches. However, when dealing with an input current source, the counterpart current-source-mode (CSM) converters are much less known. This article derives all single-input dual-output (SIDO) converters that inherently achieves no cross regulation using both VSM and CSM buck and boost converters, and provides a detailed comparison of the different SIDO configurations in terms of step-up and step-down functions, connection type, number of ground-referenced drivers, number of inductors, number of capacitors, voltage stress, and current stress. The control requirements for independent regulation of the two outputs are discussed. For illustration purposes, one specific CSM SIDO converter is presented and its detailed operation and design considerations are discussed. Finally, experimental results are presented to verify the analytical findings. [ABSTRACT FROM AUTHOR]

Due to the extremely complex regional geological tectonic movements in the Alpide Himalayan seismic belt with the dense population and rapid economic development, the frequent seismic activity has caused huge concern. In geology, the research on the spatiotemporal characteristics of seismic activity in different areas at different scales has always been valuable to explore the mechanism of seismic activity for further simulation and prediction of the seismic activity. Using the spatial autocorrelation analysis in this study, we analyzed the spatiotemporal dynamic characteristics of seismic activity in the Alpide Himalayan seismic belt. According to the historical earthquake list (from 1973 to 2017), the data are divided into five periods. Compared with the commonality and diversity of the spatiotemporal characteristics of seismic activity in different periods, it shows that: there is a positive spatial autocorrelation in each period, which proves the spatial aggregation of the seismic activity in the Alpide Himalayan seismic belt. Nevertheless, over time, the spatial aggregation distribution is gradually diminishing from 1973 to 2017; From the Local Spatial Autocorrelation analysis, the spatial aggregation characteristics of seismic activity change with time and have a significant differentiation among the regions. According to the comparison of Local Spatial Autocorrelation characteristics in different periods, seismic activities in the Alpide Himalayan seismic belt were consistent with the periodic characteristics. Assuming the alternating seismic calm period and active period, we could notice that it turned from the active period to the calm period around 2008, which is the most recent turning point between the active and calm periods. At last, the spatio-temporal dynamic characteristics of the seismic activity in the Alpide Himalayan seismic belt is not only consistent with the formation mechanism of seismic activity but also represents the spatial disparity of the geological tectonic movements. It is the feasibility and effectiveness to explore the seismic mechanism based on spatio-temporal dynamic characteristics of the seismic activity. [ABSTRACT FROM AUTHOR]

The amount of protein thiols play a crucial role in maintaining the cellular redox homeostasis and have significant implications to indicate a series of diseases. Therefore, it is necessary to develop an ideal probe for protein thiol detection in a simple and readily implementable method. Consequently, a water-soluble and incubate-free fluorescent environment-sensitive probe DMTs-OCC was synthesized using 7-diethylamincoumarin as the fluorophore and 4-(5-Methanesulfonyl- [1,2,3,4]tetrazol-1-yl)-phenol (MSTP) as a thiol receptor reagent. The blue-shift emission spectra of probe DMTs-OCC was observed by ultrafast binding to protein sulfhydryl groups from the excited intramolecular charge transfer (ICT) to the twisted intramolecular charge transfer (TICT) conversion process in aqueous solution. The experimental results showed that probe DMTs-OCC exhibited an excellent selectivity to protein thiols and biocompatibility in aqueous solution, as well as terrific cell membrane permeability which enabled the successful visualization of BSA protein thiol in living cells. Moreover, no excess probe was cleaned and no incubation time was needed in cell experiments. Therefore, it could provide a new method to the construction of fluorescent probes for protein thiols labelling and visualization. Image 1 • A new chemical sensor for protein thiols visualization was designed and synthesized. • Probe DMTs-OCC exhibits ultrafast selectively detect protein thiols, and incubate-free fluorescent environment-sensitive. • Probe DMTs-OCC was successfully visualized protein thiols in living cells. [ABSTRACT FROM AUTHOR]

An upright GO (UGO) modified screen-printed electrode was prepared with the help of the external magnetic field for improving its electrochemical performance. The ratio of GO: Nafion and the magnetic field intensity on the properties of UGO were examined by scanning electron microscope, cyclic voltammetry and electrochemical impedance spectroscopy. The magnetic field intensity does not influence the electron transfer kinetics but increase the number of active sites and therefore enhance the electroactive surface area. In addition, the UGO electrode that was electrodeposited Ni nanoparticles (denotes as Ni NPs/UGO modified electrode) display excellent oxidation towards glycine using chronoamperometry. The Ni NPs/UGO modified electrode indicated an excellent performance for electrochemical COD (chemical oxide demand) analysis with a linear detection range of 0.1–400 mg/L and a lower detection limit of 0.02 mg/L. Moreover, this Ni NPs/UGO modified electrode can be applied to the rapid determination of COD in general real water samples. The results were in agreement with those obtained by using the standard method (ISO 6060). Image 1 • Upright GO (UGO) was prepared with the help of external magnetic field. • Magnetic field increases the number of active sites and enhances electroactive surface area. • Ni NPs/UGO for COD based on glycine electrochemical oxidation. [ABSTRACT FROM AUTHOR]

Single-input multioutput converters, constructed by interconnecting dc–dc converters, are used in various applications with advantages of high scalability, low component stress, and power distribution flexibility. This article presents a complete family of two-stage configurations of interconnected dc–dc converters that include conventional voltage-source-mode (VSM) converters and the less known current-source-mode (CSM) converters, covering all possible termination types and connection styles. Derivation of 16 possible configurations is presented. These configurations are then compared in terms of power-sharing capability, extended flexibility, mutual effects among interconnected modules, basic control requirements, and load characteristics. On this basis, advantages and disadvantages of different configurations are given. Suitable applications and existing (known) configurations are reviewed, aiming to provide essential information for the design of interconnected converters for different application scenarios. As an illustrative example, a two-stage configuration consisting of a VSM converter as the prestage and two series-connected CSM converters as the poststage is proposed to drive light-emitting diodes under high-input-voltage conditions. [ABSTRACT FROM AUTHOR]

A novel turn-on fluorescent probe with barbituric acid as a unique recognition group has been rationally designed and synthesized using a facile method for detecting hydrazine. The 5-((7-(dimethylamino)-4,5-dihydronaphtho [1,2-b] thiophen-2-yl)methylene)pyrimidine-2,4,6 (1H,3H,5H)-trione (DPT) probe displays a large emission signal ratio variation (more than a 40-fold enhancement) in the presence of hydrazine under neutral conditions. Interestingly, a novel recognition mechanism based on a hydrazine-triggered addition–cyclisation-retro aldol was proposed and confirmed. Additionally, the DPT probe exhibits a low detection limit (5 × 10−8 M), applicable to the physiological pH range (3–12), a broad linear response range for hydrazine concentrations between 0 and 34 μM and a large Stokes shift (147 nm) for hydrazine detection in aqueous solution. Moreover, the DPT probe was successfully implemented for hydrazine imaging in vivo. [ABSTRACT FROM AUTHOR]

In this paper, a two-stage transformerless multiple-output converter is proposed for applications requiring a high voltage step-down ratio. The proposed circuit transfers power via a current interface and the use of current-source-mode (CSM) converters, resulting in low voltage stress and drastically simplified control. The first stage of this configuration is regulated to provide a constant current to the second stage. The second stage consists of series-connected CSM boost converters. The high step-down ratio of the proposed configuration reduces the voltage stress in the switches of the second stage. The series-connected CSM converters are inherently independent of each other, leading to a very simple control scheme without the need for decoupling of the input voltage of the interconnected converters. Input voltage variation to the system will not affect the input voltage of the second stage. Load variation in one output will not affect the other outputs. If one or more CSM converters are shorted, there is no impact on other converters. These advantages enable a high scalability. Besides, the first stage of the proposed configuration can operate both in continuous conduction mode (CCM) and discontinuous conduction mode (DCM) with the same control strategy. This feature leads to a low control complexity and elimination of inductors. The performance of the proposed converter is illustrated with a laboratory prototype driving light emitting diodes (LEDs). [ABSTRACT FROM AUTHOR]

Wildfire causes environmental, economic, and human problems or losses. This study reviewed wildfires induced by lightning strikes. This review focuses on the investigations of lightning mechanisms in the laboratory. Also, the paper aims to discuss some of the modeling studies on lightning-induced wildfires at different geographical locations using satellite-recorded lightning data and different statistical analyses. This review established that irrespective of the different models used to predict lightning wildfires, there is still a lack of understanding of the lightning-strike ignition mechanism; few experiments have been modeled to establish the dynamics of lightning-strike ignition. Therefore, further research needs to be carried out in this area to understand lightning ignition. It was ascertained from the various statistical modeling that lightning-induced wildfires are exacerbated by the abundant availability of fuel with a lower moisture content and high lightning efficiency. Moreover, because of changes in the climate and weather conditions, i.e., harsh weather and climate conditions due to anthropogenic activities, lightning-induced ignition wildfires have increased over the years, and they are expected to increase in the future if the climate and weather conditions continue to aggravate. Although various modeling studies have identified that lightning-induced wildfires have increased recently, no preventive measures have been conclusively proposed to reduce lightning-caused wildfires. Hence, this aspect of research has to be given critical attention. This review presents information that gives a profound understanding of lightning-induced wildfires, especially factors that influence lightning wildfires, and the state-of-the-art research that has been completed to understand lightning-induced wildfires. [ABSTRACT FROM AUTHOR]

Herein, a strategy for fabricating wallpaper-based smart fire-warning systems to monitor and mitigate indoor fires is proposed. The fire-warning system, based on eco-friendly cellulose paper (CP), is produced via a simple dip-coating technique and provides flexibility, rapid low-temperature warning, and novel local and remote wireless signal conversion capability. Specifically, this fire-warning system can balance flexibility and flame retardancy, reducing the negative impact on the mechanical properties after adding flame retardants. Furthermore, the proposed fire-warning system meets the critical requirement of a fast low-temperature warning, showing warning messages within 2 s under 250 ºC, decreasing the response temperature below the combustion temperature of common materials (＞300 ºC). Moreover, the luminosity and temperature data collected can be sent to local and remote computers by wireless conversion. This work gives insight into the new generation of low-temperature smart fire-warning systems, including the contribution of wireless warning signal transmission to achieve smart and efficient fire detection. [Display omitted] • Eco-friend wallpaper-based fire alarm responds to a low temperature of 250 ºC fast. • This fire alarm optimizes the balance between flexibility and flame retardancy. • A new thermo-sensor coupled with a luminosity sensor is used for signal conversion. • Local and remote wireless monitoring can be achieved through the network. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrogen accumulation was promoted by 1.3-folds at 50 mg/kg TSS Phenanthrene. • Pyruvate conversion to reduced ferredoxin for hydrogen production was enhanced. • Hydrogen consumption with CO 2 for acetyl-coenzyme A generation was suppressed. • Genes for oxidative ferredoxin reduction were up-regulated. • Genes for 5-methyltetrahydrofolate synthesis were down-regulated. The influence of phenanthrene (PHE), a general polycyclic aromatic hydrocarbon in waste activated sludge, on sludge alkaline dark fermentation for hydrogen accumulation was investigated prospectively. The yield of hydrogen was 16.2 mL/g TSS with 50 mg/kg TSS PHE, which was 1.3-fold greater than that of the control. Mechanism research demonstrated that hydrogen production and the abundance of functional microorganisms were facilitated, whereas those of homoacetogenesis were reduced. The activity of pyruvate ferredoxin oxidoreductase in the conversion of pyruvate to reduced ferredoxin for hydrogen production was promoted by 57.2%, and that of carbon monoxide dehydrogenase and formyltetrahydrofolate synthetase, closely associated with hydrogen consumption, was suppressed by 60.5% and 55.9%, respectively. Moreover, the encoding genes involved in pyruvate metabolism were significantly up-regulated, while genes related to consuming hydrogen to reduce carbon dioxide and produce 5-methyltetrahydrofolate were down-regulated. This study notably illustrates the effect of PHE on hydrogen accumulation from metabolic pathways. [ABSTRACT FROM AUTHOR]

In this study, MnFe2O4 nanoclusters were prepared as bioprobes to establish a lateral‐flow immunochromatographic assay (LFIA) for the rapid and quantitative detection of D‐dimer for the first time. The magnetic properties of the magnetic labels play a key role in the quantitative detection of biomolecules. The 47.3‐nm MnFe2O4 magnetic nanoclusters (MNCs) with good dispersion and high saturation magnetization (76 emu/g) were fabricated via thermal decomposition of Fe(acac)3 with Mn(acac)2. The prepared MnFe2O4 MNCs were well dispersed in water because the surfaces were fully covered with 3,4‐dihydroxyhydrocinnamic acid (DHCA) molecules by ligand exchange. Anti‐D‐dimer antibodies were coupled on the surface of MnFe2O4 MNCs, and the target protein, D‐dimer, was detected, in the range 0.05–6 μg/mL. This assay provides a promising platform for D‐dimer detection for point‐of‐care diagnosis. MnFe2O4 nanoclusters with good dispersion and high saturation magnetization were fabricated via thermal decomposition and successfully prepared as bioprobes to establish a lateral‐flow immunochromatographic assay (LFIA) for the rapid and quantitative detection of D‐dimer for the first time. [ABSTRACT FROM AUTHOR]

Streptococcus mutans, a facultatively aerobic and Gram‐positive bacterium, is the primary causative agent of dental caries and contributes to the multispecies biofilm known as dental plaque. In this study, the aromatic‐amino‐acid aminotransferase from Streptococcus mutans (SmAroAT) was recombinantly expressed in Escherichia coli. An effective purification protocol was established. The recombinant protein was crystallized using the hanging‐drop vapor‐diffusion method with PEG 3350 as the primary precipitant. The crystal structure of SmAroAT was solved at 2.2 Å resolution by the molecular‐replacement method. Structural analysis indicated that the proteins of the aromatic‐amino‐acid aminotransferase family have conserved structural elements that might play a role in substrate binding. These results may help in obtaining a better understanding of the catabolism and biosynthesis of aromatic amino acids. The crystal structure of the aromatic‐amino‐acid aminotransferase from Streptococcus mutans was solved at 2.2 Å resolution by the molecular‐replacement method. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Benzoate-to-PHA conversion by P. putida KT2440 was demonstrated for the first time. • Nitrogen supply condition acted as the trigger of the synthesis of PHA monomers. • Two distinct PHA synthesis patterns were revealed by kinetic modeling. Abstract Nitrogen supply is critical to the synthesis of intracellular PHA in various bacteria. However, the specific role of the nitrogen in synthesizing PHA from benzoate, a lignin model compound use for the study of bacteria catabolism of aromatics, is still not clear. In this study, two culture conditions were maintained for Pseudomonas putida KT2440 to produce PHA using benzoate as a carbon source. Under nitrogen-limited and surplus conditions, the accumulation of PHA was to 37.3% and 0.25% of cell dry weight, respectively. A model fit to the kinetics of biomass growth and PHA accumulation showed good agreement with data. GC–MS and NMR showed that PHA contained six hydroxyl fatty acid monomers under nitrogen-limited conditions, while two monomers were identified under nitrogen surplus conditions. The average molecular weight of PHA increased after the nitrogen source was exhausted. These results provide a promising strategy for optimization of lignin to PHA yields. [ABSTRACT FROM AUTHOR]

Many countries provide inexpensive public housing to citizens and residents, whereas foreigners are only allowed to purchase relatively scarce and expensive private housing. Undoubtedly, the growth in native (foreign) population size will directly contribute to higher public (private) housing price, and indirectly induce higher private (public) housing price via general equilibrium effects. The question is how to quantitatively evaluate the magnitude of each impact. To address this issue, we propose a dynamic general equilibrium framework with heterogeneous native and foreign agents interacting in both public and private housing markets. Natives can upgrade from public to private housing over their lifetime. We also allow the option for foreigners to choose to obtain permanent residency and then compete with natives in the public housing market. We calibrate the model into the Singapore economy between 1993 and 2015. The model accounts for about 85.7% of private housing price growth and 46.2% of public housing growth in the data. The decomposition exercises suggest that native population growth can generate about 67.0% of private housing price growth, while the growth of the foreign population can generate about 7.05% of public housing price growth. Finally, when borrowing is not allowed, the demand for private housing decreases, and this pushes down the private housing price. [ABSTRACT FROM AUTHOR]

• Phosphate release during POM photodegradation was characterized by FT-ICR MS. • Organic phosphorus in POM participated in the photochemical reactions. • Unsaturated P-containing formulas in POM were preferentially photodegraded. • 3CDOM* was mainly responsible for POM photodegradation in aquatic environment. Phosphate release from particulate organic matter (POM) dominates phosphorus (P) cycling in aquatic ecosystems. However, the mechanisms underlying P release from POM remain poorly understood because of complex fractionation and analytical challenges. In this study, the release of dissolved inorganic phosphate (DIP) during POM photodegradation was assessed using excitation–emission matrix (EEM) fluorescence spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). POM in suspension was significantly photodegraded under light irradiation, concomitantly with the production and release of DIP in the aqueous solution. Chemical sequential extraction revealed that organic phosphorus (OP) in POM participated in photochemical reactions. Moreover, FT-ICR MS analysis revealed that the average molecular weight of P-containing formulas decreased from 374.2 to 340.1 Da. Formulas containing P with a lower oxidation degree and unsaturation were preferentially photodegraded, generating oxygen-enriched and saturated formula compounds, such as protein- and carbohydrate-like P-containing formulas, benefiting further utilization of P by organisms. Reactive oxygen species played an important role in the photodegradation of POM, and excited triplet state chromophoric dissolved organic matter (3CDOM*) was mainly responsible for POM photodegradation. These results provide new insights into the P biogeochemical cycle and POM photodegradation in aquatic ecosystems. [Display omitted] [ABSTRACT FROM AUTHOR]

The p H is a critical variable for carbon storage in saline aquifers because it affects the reaction rate and equilibrium state of the reservoir rocks, thus influencing the rates of mineral dissolution or precipitation and the integrity of caprocks. In this work, high-pressure p H and Ag/AgCl-reference electrodes were used to measure the p H of CO 2 -saturated aqueous solutions of NaCl and NaHCO 3 . The expanded uncertainty of the p H measurements is 0.20 at 95% probability. For CO 2 -saturated NaCl(aq), measurements were carried out at total pressures from (0.37 to 15.3) MPa and temperatures from (308 to 373) K with NaCl molalities of (1, 3 and 5) mol·kg −1 . For CO 2 -saturated NaHCO 3 (aq), the p H was measured at total pressures from (0.2 to 15.3) MPa and temperatures from (308 to 353) K with NaHCO 3 molalities of (0.01, 0.1 and 1) mol·kg −1 . The p H was found to decrease with increase in pressure and with decrease in temperature for both CO 2 -saturated NaCl and NaHCO 3 solutions. For CO 2 -saturated NaCl(aq), the p H was observed to decrease with increase of salt molality, while for CO 2 -saturated NaHCO 3 , the opposite behaviour was observed. The results have been compared with predictions obtained from the PHREEQC geochemical simulator (version 3.3.9) incorporating the Pitzer activity-coefficient model with parameters taken from the literature. For CO 2 -saturated NaCl(aq), agreement to within ±0.2 p H units was observed in most cases, although deviations of up to 0.3 were found at the highest molality. In the case of CO 2 -saturated NaHCO 3 (aq), the experimental data were found to deviate increasingly from the model with increasing salt molality and, at 1 mol·kg −1 , the model underestimated the p H by between 0.3 and 0.7 units. [ABSTRACT FROM AUTHOR]

One typical joint in steel tube tower, i.e. the tube-gusset KT-joints stiffened by 1/4 ring plates, has been paid attention lately due to its merits about reasonable stress distribution and low cost. But the relevant design theory lags obviously other than design recommendations from JSSC and CIDECT. However they are proved less effective with regard to certain failure mode. For this reason, the paper has proposed one design formula to make up the deficit based on yield line theory. Finally the proposed formula is testified to be more accurate and versatile than other design rules. [ABSTRACT FROM AUTHOR]

In previous studies, resuspended sediments that were exposed to simulated solar irradiation could release dissolved phosphate (PO 4 3 − ). However, the mechanisms of phosphate release remain unclear. In this research, a battery of experiments was performed to reveal the mechanisms of the photochemical release of phosphate from resuspended sediments of a shallow eutrophic lake under solar irradiation. The results show that the PO 4 3 − released in resuspended sediments was significantly higher than that in the dark control or in water alone after treatment with solar irradiation for 6 h. The results of sequential chemical extractions showed that the concentrations of labile organic, moderately labile organic and residual organic phosphorus decreased in the resuspended sediment after 6 h of solar irradiation; of these, moderately labile organic phosphorus was the greatest contributor to the release of dissolved phosphate in resuspended sediment. Orthophosphate, phosphate monoesters, phosphate diesters and pyrophosphate were detected with 31 P NMR. It is worth mentioning that the diester-P and pyro-P species disappeared after 6 h of irradiation. In addition, enzyme activity and radical trapping experiments were applied to identify the roles of biomineralization and photochemical degradation during phosphate release from resuspended sediments under solar irradiation. The amount of PO 4 3 − released in fresh sediment was greater than that in the autoclaved sediment, which should be attributed to the higher alkaline phosphatase activity in the fresh sediment. However, the PO 4 3 − released from the photochemical degradation of organic phosphorus is the primary phosphate source during sediment resuspension under 6 h of solar irradiation. The phosphate photorelease was inhibited when methanol was added to the suspension and decreased significantly when the concentration of methanol was increased from 0.5 M to 2.0 M. All of these results suggest that photochemical processes may lead to PO 4 3 − release from sediment in aquatic environments. [ABSTRACT FROM AUTHOR]

• A three-dimensional data-based crater identification method is proposed to complete the crater by filling in the blind zone for high probability. • Three parameters related to terrain and sensor are varied for evaluating the consequence of crater identification: the terrain frequency, the ranging errors and the angle errors. • The proposed method achieves the completion rate of exceeding 84.18%, and the detectivity probability more than 80.58%. • This three-dimensional environment perception simulation for crater identification will be instructive for Lunar exploration. Crater identification is an important task of environment perception, which is benefit for path planning and safe campaign of Lunar rover. In order to overcome the partial missing of point cloud obtained by LiDAR, a three-dimensional data-based crater identification method is proposed to complete the crater by filling in the blind zone for high probability detection, which can be evaluated by completion rate and detection probability of the negative obstacle area in the occupancy grid map, respectively. To obtain a reasonable identification of the craters under various terrain conditions, three parameters related to the terrain and the sensor are varied for evaluating the consequence of crater identification: the terrain frequency, the ranging errors and the angle errors. In simulation experiments, craters with various parameters locate on rolling terrain. The parameters settings used in simulation experiments include the diameter of craters (2 m to 20 m), terrain frequency (>20 m−1), ranging error (<0.07 m) and vertical angle error (<0.3°). The simulation experimental results showed that the proposed method achieves the completion rate of exceeding 84.18 % for providing the complete craters, and the detection probability more than 80.58 % to create the safe occupancy grid map for path planning. This three-dimensional environment perception simulation for crater identification will be instructive for in-situ surface data evaluation and Lunar exploration. [ABSTRACT FROM AUTHOR]

Plant phenology modulates water and energy exchanges between the biosphere and the atmosphere and therefore influences planetary boundary layer (PBL) dynamics. Here we conduct a modeling experiment using the Community Earth System Model version 2, where plant phenology is prescribed based on satellite climatology in the control experiment. We then shift the timing of vegetation green-up and senescence in North America by one month earlier and later and investigate how shifting phenology could influence land-atmosphere interactions. Altering plant phenology modifies boundary layer fluxes through both direct influences on evapotranspiration and absorbed solar radiation and indirect effects through changes in low cloud fraction. The prescribed shift in phenology has significant but different influences on PBL dynamics and land-atmosphere coupling in the spring and fall in the Great Plains and Eastern United States. In the spring, earlier plant phenology significantly decreases PBL height in the Great Plains by more than 100 m. In the autumn, the Great Plains experience a significant increase in PBL height of over 100 m in the early fall while Eastern US exhibits a significant increase in the late fall when prescribed senescence is shifted earlier. As shifts in plant phenology alone can cause significant changes in PBL conditions at the seasonal timescale in the Great Plains and Eastern US, our experiments can help infer the potential location and magnitude of phenology-induced changes and provide useful information for observation-based analysis and model evaluation. [ABSTRACT FROM AUTHOR]

• A piecewise distance effect function and the Blinn-Phong model-based angle effect correction is proposed to correct the raw intensity for road marking detection. • The background data-driven angle effect function (BDAF) is beneficial for enhancing marking and road classification. • The incidence angle span (IAS) has a major influence on intensity correction of road marking, the road marking separability was improved by 35%@535 pt/m2 when IAS was increased from 3.17° to 13.5°. The intensity data recorded by light detection and ranging (LiDAR) contains the spectral characteristics of a scanned target, making it an essential source of information in mobile laser scanning (MLS) related applications. However, the raw intensity can be distorted by distance and incidence angle, obstructing its use in autonomous driving. To correct the intensity distortion, an automatic demarcation selection, based on distance effect function, and a Blinn-Phong model-based angle effect correction, have been proposed to correct the raw intensity, establishing the relationship between intensity correction performance and the influencing factors, including modeling data selection, incidence angle span (IAS) and point cloud density. Separability (SEP) and balanced F score (BFS) were used to evaluate the separability, accuracy and totality of road marking detection. Experimental results showed that the background data-driven angle effect function (BDAF) used was beneficial for enhancing marking and road classification. IAS has a major influence on correcting intensity performance. SEP was improved by 35% when IAS was increased from 3.17° to 13.5°, with point density of 535 pt/m2. The IAS threshold could be adjusted according to the instrument performance used. It offers a meaningful investigation of detection and classification of planar target using corrected MLS intensity. [ABSTRACT FROM AUTHOR]

Background: Toenails play a great part in protecting toes and peripheral soft tissues, simultaneously playing a cosmetic role. The ideal treatment should result in a functional and aesthetic outcome. Objective: To describe a novel, aesthetic and minimally invasive method to treat ingrown toenail. Methods: We retrospectively analyzed 436 lesions of 395 ingrown toes in 353 patients with a mean age of 26.0 ± 13.4 (range 10–55) from June 2014 to March 2020 in our department. A novel cosmetic approach for partial matricectomy in treating ingrown toenails was undergone. The average follow‐up time was 27.5 ± 2.8 months. The average period prior to work resumption, recurrence rate, and infection rate were measured. Mean pain Visual Analogue Scale (VAS) and Mean satisfaction VAS were used to evaluate the foot appearance. Results: The average period prior work resumption was 2.2 ± 2.1 days (range, 0–7 days). The recurrence rate was 1.6% (7 lesions in 6 patients) at more than 2 years of follow‐up. There was no critical complication except infection (0.46%). Mean pain VAS reduced from a preoperative score of 7.7 ± 1.5 points (range, 6–10 points) to a postoperative 3‐day score of 2.2 ± 1.0 points (range, 1–4 points; p < 0.001) while Mean satisfaction VAS improved from 1.5 ± 1.3 points (range, 0–3 points) to 9.2 ± 0.6 points (range, 8–10 points; p < 0.001). Conclusion: Our proposed approach is minimally invasive relative to conventional methods, which can achieve comparable efficacy to treat ingrown toenails with granulation tissue. Therefore, it can serve as another option to treat this specific type of ingrown toenails. [ABSTRACT FROM AUTHOR]

Background: The differences in fat deposition sites exhibit varying degrees of systemic inflammatory responses and organ damage, especially in obese individuals with excessive visceral fat. Visceral fat, which is closely related to an increase in mortality rates related to heart and liver diseases. However, few studies have analysed the differences in heart and liver indicators and their correlation among groups based on the abdominal visceral fat area (AVFA). Objective: Clarifying the differences in and correlations of heart and liver indicators among groups with different severities of AVFA by magnetic resonance imaging (MRI). Methods: Sixty-nine subjects with obesity were enrolled. The study group consisted of forty-one individuals (AVFA ≥ 150 cm2), and the control group consisted of twenty-eight individuals (100 cm2 ≤ AVFA < 150 cm2). The differences in and correlations between clinical, laboratory, and MRI indicators of the heart and liver between the two groups were analysed. Results: In the study group, the incidences of type 2 diabetes mellitus (T2DM) and insulin resistance were higher, and liver function indicators were worse. The left ventricular eccentricity ratio (LVER), left ventricular mass (LVM) and global peak wall thickness (GPWT) were higher in the study group than in the control group (P = 0.002, P = 0.001, P = 0.03), and the left ventricle global longitudinal strain (LVGLS) was lower in the study group than in the control group (P = 0.016). The pericardiac adipose tissue volume (PATV) and myocardial proton density fat fraction (M-PDFF) were higher in the study group than in the control group (P = 0.001, P = 0.001). The hepatic proton density fat fraction (H-PDFF) and abdominal subcutaneous fat area (ASFA) were higher in the study group than in the control group (P < 0.001, P = 0.012). There was a moderate positive correlation (ρ = 0.39–0.59, P < 0.001) between the AVFA and LVER, LVM, GPWT, LVGLS, and H-PDFF. There was no difference in right ventricular and most left ventricular systolic and diastolic function between the two groups. Conclusion: The high AVFA group had a larger LVM, GPWT and PATV, more obvious changes in LVER, impaired left ventricular diastolic function, an increased risk of heart disease, and more severe hepatic fat deposition and liver injury. Therefore, there is a correlation between the amount of visceral adipose tissue and subclinical cardiac changes and liver injury. [ABSTRACT FROM AUTHOR]