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The process of transformation and superposition from the Paleo-Asian Ocean to the Paleo-Pacific Ocean tectonic systems have been a critical scientific issue. However, the final closure of the Paleo-Asian Ocean and the initial subduction time of the Paleo-Pacific Ocean, together with the conversion between them in Northeast China, still remain controversial. The Triassic granites in the Jiamusi Block are located in the key position of Northeast China, recording the conversion process of two tectonic domains. Through systematic geochronology and geochemical studies, it can provide important constraints for revealing the superposition and conversion mechanism of the Paleo-Asian Ocean and the Paleo-Pacific Ocean and the early subduction history of the Paleo-Pacific Ocean plate. In this study, the granites in Jiamusi Block were formed in the Early–Middle Triassic (250–245 Ma), characterized by high Si, rich alkali, poor Mg, and are obviously enriched in light rare earth elements and large ion lithophile elements, depleting in high field strength elements such as Nb, Ta, and Ti. They have typical characteristics of continental magmatic arc, deriving from partial melting of amphibolite facies and garnet amphibolite facies mafic lower crust. Combined with zircon Hf isotope results, zircon εHf(t) values are −6.52 to + 9.79, and the two-stage Hf model ages are 0.6–1.7 Ga, indicating that the magma should be derived from a relative younger crustal source, and some ancient materials may be added. Moreover, based on the spatial-temporal framework and Hf isotope characteristics of magmatism in Northeast China, we believe that the Jiamusi Block belonged to an exotic block. Meanwhile, combined with geochronological and geochemical data of igneous rocks on the Jiamusi Block, we suggest that the evolution of Jiamusi Block was dominated by the Paleo-Pacific Ocean rather than Paleo-Asian Ocean during the Triassic, which means the subduction of Paleo-Pacific Ocean plate initiated at least in Early Triassic. [ABSTRACT FROM AUTHOR]

Foodborne pathogenic infection has brought multifaceted issues to human life, leading to an urgent demand for advanced detection technologies. CRISPR/Cas-based biosensors have the potential to address various challenges that exist in conventional assays such as insensitivity, long turnaround time and complex pretreatments. In this perspective, we review the relevant strategies of CRISPR/Cas-assisted diagnostics on foodborne pathogens, focusing on biosensing platforms for foodborne pathogens based on fluorescence, colorimetric, (electro)chemiluminescence, electrochemical, and surface-enhanced Raman scattering detection. It summarizes their detection principles by the clarification of foodborne pathogenic bacteria, fungi, and viruses. Finally, we discuss the current challenges or technical barriers of these methods against broad application, and put forward alternative solutions to improve CRISPR/Cas potential for food safety. [ABSTRACT FROM AUTHOR]

Institutional theory holds that local governance is essential in shaping regional economic activity. This study evaluates whether local economic growth targets offset the detrimental effect of nationwide policy uncertainty on local business performance. Regression analyses of data from industrial firms and manually collected data on city economic growth targets in China show that higher local growth targets result in greater corporate investment, conditional on nationwide policy uncertainty, and that the impact is substantial through financial subsidies and allocating credit resources. However, local discretion in economic growth target setting might cause investment misallocation and efficiency loss. [ABSTRACT FROM AUTHOR]

Anammox is one of the most innovative nitrogen removal technologies, while its functional bacteria-anaerobic ammonia-oxidizing bacteria (AAOB) is sensitive to the impurities in the wastewater. In this study, the long-term effects of sulfide at different concentrations (0, 5, 10, 20, 30, 50, 25 mg L−1) on low substrate Anammox process were studied. The results showed that when the sulfide was 25–30 mg L−1, AAOB was well coupled with sulfide-denitrifying bacteria and the total nitrogen removal efficiency (TNRE) reached a maximum of 91.0%. The hydroxylamine oxidoreductase activity and Heme-c reached 1.678 EU g−1 SS and 0.0023 mmol g−1 SS, respectively, with the hzo and nosZ gene concentrations as 2.52 × 108 and 4.45 × 107 copies mL−1. 50 mg L−1 sulfide inhibited the nitrogen removal by AAOB, resulting in the TNRE decreasing to 81.7%. The experimental results provide a reference for the practical application of Anammox in treating sulfur-containing wastewater. [ABSTRACT FROM AUTHOR]

The fault-tolerant control (FTC) issue for a class of interconnected wave-distributed parameter systems is addressed by using the inclusion principle. Both subsystem faults and coupling faults are considered. First, the original system is expanded into an equivalent decoupled system. The main structure of the expanded system consists of multiple pair-wise subsystems. Second, the pair-wise fault-tolerant controllers are designed to stabilise the pair-wise subsystems, which can compensate for the effects of subsystem faults and major coupling faults. Third, a coordinated fault-tolerant controller with a suitable coordinated compensator for the expanded system is constructed according to the pair-wise fault-tolerant controllers of all subsystems. The coordinated compensator is used to compensate for the effects of other minor interconnections and coupling faults, and the coordinated controller is designed for the expanded system. Furthermore, the fault-tolerant controller is obtained to guarantee asymptotical stability of the faulty interconnected wave system by satisfying the contraction condition. The numerical experiments are presented to illustrate the effectiveness of the FTC method. [ABSTRACT FROM AUTHOR]

In this study, multi-level laminate-network boron nitride nanosheets (BNNSs)/TC4 composite with interlayer interlocking was fabricated using a facile direct ink writing (DIW) technique. In-situ 3D nano-configurations consisting of BNNSs and TiBx nanophases distributed around TC4 matrix particles formed the first-level network structure, while the above composite layers and TC4 layers with interlayer interlocking formed the second-level laminate structure. It exhibits a comparable high tensile strength of around 1203 MPa, compared to composites with a single-network structure, while demonstrating a 20% higher toughness of 55.8 MJ/m3. The interlayer interlocking microstructure interlayer could be responsible for the strength enhancement, which benefits the stress transfer between layers. The improved ductility could be attributed to the crack blocking adduced by the laminate structure and the 3D network in the composite layers. [ABSTRACT FROM AUTHOR]

In this work, different transformed β matrix was obtained in Ti–5Al–7.5 V alloy. The alloy with equiaxed αp phase and transformed β matrix containing α′ martensite and β phase exhibits good combination of strength and plasticity, as well as a high work hardening rate. A concurrent operation of stress-induced α″ martensitic transformation, deformation twinning and dislocation slips was observed governing the deformation process of this alloy. The alloy with equiaxed αp phase and transformed β matrix containing secondary αs plates and retained β phase shows a high strength and plasticity but low work hardening rate, which is caused by dislocation slips. Highlights The quenched Ti–5Al–7.5 V alloy exhibits a high work hardening rate, approximately 5500 MPa. The dependence of work hardening rate of Ti–5Al–7.5 V alloy on transformed β matrix is revealed. Concurrent operations of stress-induced α″ martensitic transformation, deformation twinning and dislocation slips govern deformation of the studied alloy. [ABSTRACT FROM AUTHOR]

With the increasing of tunnel mileage, one of the most vital problems of broad-scale structures is the intelligent identification and location of structural defects, which require massive data storage capacity and high data processing efficiency. The full-field point cloud data collected by terrestrial laser scanning (TLS) can be extracted to construct three-dimensional measured models more accurately, therefore, the fusion of TLS and the finite element method (FEM) is particularly beneficial to the deformation analysis of tunnel structures. This paper combines numerical simulation and full-field measurement to interactively verify the reliability of deformation analysis based on FEM simulation and point cloud processing. The innovation of this paper is that a three-dimensional FEM is validated through the measured point cloud data of the tunnel structure. The result of this study indicated that FEM simulation and the structural health monitoring analysis are consistent. [ABSTRACT FROM AUTHOR]

This research explores the impact of monetary policy on the growth rate of total factor productivity (TFPG) and innovation efficiency (IE) through panel data of 30 countries from 1983 to 2018 by the bias-corrected fixed-effect dynamic (BCFE) model. We find that tight monetary policy negatively impacts the growth rate of total factor productivity (TFPG) and innovation efficiency (IE), which is still valid after a series of robustness tests. We then perform sub-sample regressions, and the results show that countries with higher government efficiency, higher financial development, and stricter environmental policy can reduce the negative impact of tightening monetary policy on total factor productivity and innovation efficiency. Our research illustrates that a tightening monetary policy not only adversely impacts total factor productivity but also influences the main driving force of its growth-innovation efficiency. [ABSTRACT FROM AUTHOR]

The temperature plays a critical role in atmospheric research. A measurement system based on Rayleigh scattering Lidar was developed in this study to detect mid and upper-level atmospheric temperature. To analyze the error introduced by the calibration point temperature, the echo signal was simulated. The continuously measured atmospheric temperature structure is stable. The measured atmospheric temperature profile follows the same trend as the atmospheric mode, as shown by comparison with different modes and balloons. The mean difference between the measured atmospheric temperature and the balloon temperature is 2.59 K, with the error mostly concentrated below 5 K. Continuous observation of atmospheric temperature using the system revealed the occurrence of temperature-induced gravity waves at a vertical wavelength from 2 to 3 km at an altitude between 30 and 45 m. Partial fragmentation occurs when energy dissipation is performed in the low-frequency mode from 38 to 45 km. This system was demonstrated to effectively detect temperature and continuously observe gravity waves, with its accuracy confirmed by comparison with balloon temperature measurements. [ABSTRACT FROM AUTHOR]

In the nuclear fuel cycle, 30 vol % tributyl phosphate/kerosene is always used as the major actinide extractant. However, there is a risk of fire accident during the usage of the solvent solution. It is necessary to investigate solvent fire because of the release of radioactive materials and possible overheating and blocking of ventilation filters. This paper discusses several tests of solvent solution combustion that were carried out to analyze the safety of solvent fire. Parameters such as gas emission of solvent burning, mass loss rate, and production of aerosol were obtained and analyzed. The experimental data obtained in this paper can be useful to develop a method of solvent fire assessment and evaluate a solvent fire accident in a nuclear fuel cycle facility. [ABSTRACT FROM AUTHOR]

We study the effects of the US-China trade war on Chinese firms' investment using the detailed quarterly financial data of Chinese listed firms merged with firm-level Chinese customs data. We construct the firm-level measures of direct trade exposure and the financial measures of indirect exposures to the US-China trade tension using firms' equity responses during the trade war escalation periods. We document that the trade war reduced Chinese firms' investment by two percent. In particular, we find significant heterogeneous firms' responses to the trade war, depending on their firm characteristics. Chinese firms that are more dependent on exports to the US have lower stock returns; large firms and state-owned firms suffer more compared to small firms and private-owned ones. [ABSTRACT FROM AUTHOR]

In this article, the Carrera Unified Formulation and full Green–Lagrange nonlinear relations are employed to investigate the postbuckling behavior of laminated composite panels subjected to in-plane shear and combined loadings. The layerwise refined plate models are implemented by the efficient Lagrange expansion functions through the laminate thickness. An artificial surrounding area is assumed to model shear conditions. The accuracy of the presented model is validated based on the available literature. Then, the effects of stiffeners on the nonlinear response of panels are evaluated, and comprehensive assessments are provided for the equilibrium curves and stress distributions. [ABSTRACT FROM AUTHOR]

Objective: Hemostatic gauze application is an effective way to control major bleeding, which is the most common cause of death in trauma in both civilian and military settings. Coagulation derangement after acute exposure to high altitude might alter the effects of hemostatic gauzes. The present study aimed to observe the hemostatic effects of bio-zeolite gauze (BZG) and QuikClot Combat Gauze® (QCG) on major bleeding in rabbits acutely exposed to high altitude. Methods: Sixty rabbits were randomly and evenly divided into six groups. Animal models of simulated blast- and fragment-induced inguinal major bleeding were prepared in lower altitude and high-altitude areas, and BZG, QCG, and ordinary gauze without hemostatic material were used to control bleeding. The primary outcomes included immediate hemostasis rate, blood loss, and survival rate, while the secondary outcomes included hemodynamic parameters, laboratory examinations, and coagulation-relevant markers. Results: The overall effects of BZG and QCG were better than those of ordinary gauze, with a higher immediate hemostatic rate, less blood loss, and higher survival rate at 90 min after gauze application and higher red blood cell and platelet counts and lower creatinine level at 30 min after gauze application in lower altitude. The concentrations of coagulation factor XII and factor X in rabbits acutely exposed to high altitude were significantly lower than those in lower altitude. At high altitude, the hemostatic effects of BZG did not decrease significantly compared to those in the lower altitude, whereas those of ordinary gauze and QCG decreased significantly at high altitude compared to those in the lower altitude. Conclusions: Coagulation derangement after acute exposure to high altitude has negative effects on ordinary gauze and QCG but has no significant negative hemostatic effects on BZG. [ABSTRACT FROM AUTHOR]

The transmission rate of COVID-19 varies by location and time. A proper measure of the transmissibility of an infectious disease should be place- and time-specific, which is currently unavailable. This research aims to better understand the spatiotemporally changing transmissibility of COVID-19. It contributes to COVID-19 research in three ways. First, it presents a generally applicable modeling framework to estimate the transmissibility of COVID-19 in a specific place and time based on daily reported case data, called space-time effective reproduction number, denoted as R s t. Then, the developed model is used to create a spatiotemporal data set of R s t values at the county level in the United States. Second, it investigates relationships between R s t and dynamically changing context factors with multiple machine learning and spatial modeling techniques. The research examines the relationships from a cross-sectional perspective and a longitudinal perspective separately. The longitudinal view allows us to understand how local human dynamics and policy factors influence changes in R s t over time in the place, whereas the cross-sectional view sheds light on the demographic, socioeconomic, and environmental factors behind spatial variations of R s t at a specific time slice. Some general trends of the relationships are found, but the level of impact by each context factor varies geographically. Third, the best performing local longitudinal models have promising potential to simulate or forecast future transmissibility. The random forest and the exponential regression models based on time-series data gave the best performances. These models were further evaluated against ground truth data of county-level reported cases. Their good prediction accuracies in the case study prove that these machine learning models are promising in their ability to predict transmissibility in hypothetical or foreseeable scenarios. [ABSTRACT FROM AUTHOR]

For severe accidents, in-vessel retention (IVR) is a very effective and crucial severe accident mitigation measure. The lower head of the reactor pressure vessel plays a vital role in the IVR strategy. The failure of the lower head may lead to the release of radioactive substances into the environment. During the implementation of IVR, the lower head is in a high-temperature environment, and its main failure form is creep failure. Therefore, to ensure the successful implementation of the IVR strategy and prevent radioactive material leakage, it is necessary to conduct an in-depth analysis of the lower head. In this paper, the lower head thermal-mechanical creep failure (LHTCF) module is developed based on the theory of plate and shell and Norton-type constructive creep laws. Through the mechanical analysis of the lower head, seven failure criteria are used to evaluate the integrity of the lower head. Finally, the LHTCF module is integrated into the integrated severe accident analysis (ISAA) program, and the accuracy of the module is validated by numerical calculation of the Organisation for Economic Co-operation and Development Lower Head Failure (OLHF) experiment. Through the comprehensive judgment of different failure criteria, the final simulation results are in good agreement with the experimental data. The results show that the wall thickness at the crack decreases sharply before failure due to the effect of creep, and the stress increases abruptly at the failure time. The LHTCF module developed in this paper can accurately predict the creep behavior of the lower head, and the calculated failure time, position, and thickness distribution agree well with the experimental results. [ABSTRACT FROM AUTHOR]

With the rapid development of urban rail transit and the aging of transportation infrastructure, the demand for shield tunnel disaster detection is about to break out. Most of the traditional monitoring methods require considerable manpower and time costs, which cannot satisfy the increasing requirements of tunnel operation and maintenance. Free-form model construction and deviation mechanism analysis are investigated in this paper to monitor the geometric deformation information of shield tunnels quickly and accurately. A method for identifying geometric features of tunnel sections based on the free-form B-spline approximation is proposed. The innovation of this paper lies in the intelligent recognition of common interference targets by the residual classification method. Furthermore, various Root Mean Squared Error (RMSE) distributions are investigated, which successfully realizes and verifies the clustering analysis of certain point cloud features. [ABSTRACT FROM AUTHOR]

To solve slow speed and low accuracy of traditional detection methods of tunnel lining cracks, especially under the complicated situation of tunnel in operation, this work proposed an improved You Only Look Once version X (YOLOX) tunnel lining crack image detection algorithm. First, Mobilenetv3 was used to replace YOLOX's CSPDarknet network. The Efficient Channel Attention (ECA) module was then added to the enhanced feature extraction network, and the IOU loss function was replaced by the generalised IOU (GIOU) loss function. A tunnel crack image data set was constructed and used to compare the performance of the improved YOLOX algorithm with that of five other algorithms. The improved YOLOX algorithm solves the shortcomings of the other five algorithms. The results showed that the improved YOLOX algorithm had 82.48% F1 score and 87.28% AP value, which is higher than that of the other five algorithms at varying degrees. In addition, the data size of the improved YOLOX model was 51.2 M, which is 75.27% compressed compared to the YOLOX model. The time was 16.52 ms, and the FPS was 60.52 frames/s. Therefore, the proposed improved YOLOX algorithm can realise the high-speed, high-precision, real-time dynamic detection of tunnel lining cracks in complicated environments. [ABSTRACT FROM AUTHOR]

In order to obtain a lignin-based adsorbent with low cost, simple operation and no further modification, a calcium lignin adsorbent was prepared from chemical mechanical pulping (CMP) waste liquor by directly calcification from lime. The calcium lignin was characterized by BET, SEM, TEM, FT-IR and solid-state NMR analyses. The results showed that the molecular structure of the calcium lignin particles did not change when compared to sodium lignin, the formation mechanism of calcium lignin was revealed. The initial COD and lignin contents of CMP waste liquid were 54858 mg/L and 24.39 g/L, the conversion rate of lignin can reach 71.36% when was deal with lime. Thus, most of the lignin resources in the waste liquid were recovered. The middle-stage wastewater (MSWW) of pulping and papermaking was dealt with calcium lignin, the COD removal rate was up to 85.83%. The adsorption isotherms and kinetics were well fitted by the Langmuir model and pseudo-second-order kinetic model, respectively. Lime was regenerated from the used calcium lignin with high-temperature calcination, the conversion rate of calcium ions can reach 83.56%. Overall, the calcium lignin prepared by the one-step method exhibited great potential for effectively removing COD from middle-stage wastewater. [ABSTRACT FROM AUTHOR]

To investigate the clinical efficacy of thermal ablation in the treatment of pulmonary carcinoid (PC) tumor. Data of patients with inoperable PC diagnosed from 2000 to 2019 were obtained from the SEER database and analyzed according to different therapeutic modality: thermal ablation vs non-ablation. Propensity score matching (PSM) was used to reduce intergroup differences. Kaplan–Meier curves and the log-rank test were used to compare intergroup differences of overall survival (OS) and lung cancer-specific survival (LCSS). Cox proportional risk models were used to reveal prognostic factors. After PSM, the thermal ablation group had better OS (p <.001) and LCSS (p <.001) than the non-ablation group. Subgroup analysis stratified by age, sex, histologic type and lymph node status subgroups showed similar survival profile. In the subgroup analysis stratified by tumor size, the thermal ablation group showed better OS and LCSS than those of the non-ablation group for tumors ≤3.0 cm, not statistically significant for tumors >3.0 cm. Subgroup analysis by M stage showed that thermal ablation was superior to non-ablation in OS and LCSS for patients with M0 stage, but no significant difference was found in subgroups with distant metastatic disease. Multivariate analysis showed that thermal ablation was an independent prognostic factor for OS (HR: 0.34, 95% CI: 0.25–0.46, p <.001) and LCSS (HR: 0.23, 95%CI: 0.12–0.43, p <.001). For patients with inoperable PC, thermal ablation might be a potential treatment option, especially in M0-stage with tumor size ≤3 cm. [ABSTRACT FROM AUTHOR]

Laser-based visual perception technology is an effective way to enhance the intelligent level of tunnel operation and maintenance, which could improve the efficiency of the automatic identification and intelligent positioning of different diseases. Although various sensing and data processing methods for tunnel inspection have been studied, the research on invasion detection based on laser scanning technology is still rare. In this paper, the invasion detection of the tunnel and train is carried out based on terrestrial laser scanning data. A feature-based registration is proposed in order to fuze the tunnel and the train models accurately and automatically in the unified coordinate system, where the local contact points are set as the features and identified by means of the normal vector descriptor. The invasion analysis is achieved with the convex points, which are paired through the convex hull and polar principle. A complete and comprehensive image of the invasion analysis is generated, which offers a reality model base for the design and decision-making. The method proposed can be extended to other similar scale scenarios of invasion analysis and spatial position inspection. It is a reference for the engineering applications of the intelligent operation and maintenance of the tunnel. [ABSTRACT FROM AUTHOR]

The monitoring and prevention of cracks in tunnel structures is an essential problem and the traditional methods are arduous to suffice the rapid increasing of tunnel mileage. Many researches, nowadays, mainly focus on the automatic identification and intelligent detection of cracks. However, crack identification and localization of tunnel structures are merely preliminary for effective prevention. Therefore, how to intelligently analyze and predict the further evolution of cracks will be the top priority of tunnel disaster prevention. In this article, a novel method is proposed which combinates deep learning (DL) techniques and finite element method to detect and analyze the cracks which is significant for the intelligent prevention. The innovation of this article lies that the position of cracks is identified automatically with the DL based on Mask R-CNN method and the evolution of cracks is predicted efficiently with FEM model. [ABSTRACT FROM AUTHOR]

Controlled incorporation of bioactive hydroxyapatite (HA) into poly(lactic acid) (PLA) signifies a promising approach to design and development of biomedical-adaptive materials. Here we unravel a microwave-assisted biomineralization approach to synthesis of HA nanowhiskers (HANWs), which were characterized by well-controlled diameter (∼30 nm) and length (80 − 120 nm), combined with a desirable calcium − phosphorus ratio (Ca/P) of 1.67. A high-shear liquid dispersion (HSLD) method that provided a combination of high pressure (up to 50 kPa) and high shear rate approaching 10000 s−1 was established to fabricate homogeneous PLA/HANWs composites. In particular, upon incorporation of 30 wt % HANWs the tensile strength and elastic modulus of PLA-HA30 (76.7 MPa and 3.3 GPa) were elevated by 48% and 84% compared to those of pure PLA, respectively, as accompanied by a nearly 2-fold increase in the cell viability. This work paves a facile yet effective roadway to strong and osteoconductive PLA composites appealing for bone tissue repairing. Synopsis: Biomineralization concepts are abstracted to synthesize well-defined and bioactive HANWs, which could be uniformly dispersed in PLA biofilms by high-shear liquid exfoliation. [ABSTRACT FROM AUTHOR]

In this study, using pressurized air to split the soil between a booster tube and a plastic vertical drain (PVD), an air booster is employed to reduce clogging such that the vacuum preloading of the dredged soil is promoted. Under the framework of Hansbo's theory, an analysis method is conducted to understand the consolidation of dredged soil improved by vacuum preloading assisted by an air booster. Both increases in the consolidation stress and permeability of soil are introduced to consider the effect of the air booster on the consolidation of soil. The calculated results are compared with results of existing cases to verify the proposed method. A feasible range of increments for the consolidation stress and permeability of soil is derived from a back fit based on a coincided comparison between the calculated results and monitored data. The proposed method can be employed as a design tool to predict soil consolidation and settlement in geotechnical practice. [ABSTRACT FROM AUTHOR]

For subway safety, it is important to monitor the convergence deformation of shield tunnels in the long term. However, traditional monitoring methods are constrained by high cost and technical difficulties. Herein, improvements achieved through use of a new type of optical fiber (OF) sensor are reported. The new type of optical fiber sensor, namely, the flexible long-gauge Fiber Bragg Grating (FBG) sensor, is proposed with descriptions of design, preparation and strain sensing performance. Then, a method of assessing convergence deformation is proposed based on distributed long-gauge strain measurements. Finally, the proposed method is validated with measurements made on two full size specimens of shield segments. It is also concluded that the seam change shows a strong influence on convergence deformation. From static experiments, convergence deformation can be accurately evaluated to satisfy the demands of tunnel management. Considering the additional advantages of distributed sensing, such as sensing distance, stability and durability, the proposed method exhibits broad application prospects. [ABSTRACT FROM AUTHOR]

Automation and intelligent health monitoring technologies will be one of the most important development directions for rail transit operation and maintenance considering the continuous expansion of the scale of urban rail transit and the increase of labor costs. The highly accurate, full-field data acquisition based on vision measurement technology, which is combined with photogrammetry and three-dimensional scanning technology, is an effective way to improve the intelligence of monitoring. In this paper, accuracy tests of vision measurement and total station technology in multipoint measurement is carried out under the same conditions where the accuracy and reliability are compared according to the various datasets which are collected from experiment and testing. A novel visual measurement technology is proposed for the deformation monitoring of tunnel structures, such as settlement and convergence. The results show that the measurement system has a resolution of 0.01 mm which is better than the total station resolution, and the deviation ratios of the vertical and horizontal displacement are 1.6% and 2.5%, which demonstrate the proposed system has a good potential for practical applications in terms of resolution and accuracy. [ABSTRACT FROM AUTHOR]

Dendrocandins are characteristic chemical structures of D. officinale and have strong physiological bioactivities. In this study, a dendrocandin analogue (1) has been prepared by total synthesis (9 steps, 12.6% overall yield) in which coupling reaction and Wittig reaction as the key steps. Compound 1 was also evaluated for its anticancer activity in vitro against six human cancer cells (MCF-7, A549, A431, SW480, HepG-2 and HL-60) using MTT assays. Compound 1 showed potent cytotoxicity, with the IC50 value 16.27 ± 0.26 µM. The expression levels of apoptotic proteins indicated that compound 1 can up-regulate the expression of apoptotic proteins, leading to apoptosis. This compound suggested that it's potential as anticancer agent for further development. [ABSTRACT FROM AUTHOR]

Carbon materials have been extensively used in scientific research and industrial production. Thereby, a kind of nanospheres of carbon (NSC) was prepared from sucrose, focusing on its physical and chemical structures, getting results that: (1) the yield of NSC is in average of 30.68% of the mass of sucrose, corresponding to 61.97% of carbon conversion. (2) The diameter of NSC is in the range of 150–200 nm, containing 1351.41 m2/g of surface area, which is contributed by the pores in average of diagram of 3.32 nm. (3) The apparent molecule formula (AMF) of NSC can be expressed as C11H2O with unsaturated degree of 11, which is the sum of the numbers of double bonds and rings. (4) It contains the groups of C = C, C-C, C-O-C and C-H; especially, the ratio between the double carbon bonds and single carbon bonds is 1.0. Therefore, this research successfully prepares a kind of special carbon materials by bio-resource, and does benefit to the theory for chemical structure analysis of carbon materials. [ABSTRACT FROM AUTHOR]

Suicide remains the second leading cause of death among youths. Family-related factors are considered important determinants of children's suicidal ideation, whereas their short-/long-term influence is seldom quantified. We aim to confirm the simultaneous/lagged effects of family-related factors on the occurrence of recent suicidal ideation from childhood to young adulthood (aged from 10 to 22 years old). Data were derived from a longitudinal prospective cohort study. Participants included 2065 students who were followed up for 13 years. Generalized estimating equations were used to clarify the influential effects of family-related factors on suicidal ideation during the past month. The peak of the rate of recent suicidal ideation arrived during junior high school years. Family interaction, family support, family involvement, and parental punishment had simultaneous effects on recent suicidal ideation. Family involvement, parental conflict, and psychological control had lagged and lasting effects on suicidal ideation. Notably, the lasting protective effects of family involvement were more obvious than simultaneous effects. Providing parents with sustained support and education to improve their "positive parenting literacy" can help with their children's mental health development. This is especially the case during COVID-19 quarantine periods when families spend the most time together at home. [ABSTRACT FROM AUTHOR]

This research empirically analyzes the impact of foreign exchange futures volatility on macroeconomic variables by using data of ten trading markets from 2011 to 2020.1 Our findings illustrate that the volatility of foreign exchange futures significantly affects various macroeconomic indicators. In particular, as the volatility of foreign exchange futures increases, it reduces government budget revenue, increases the inflation rate, and has a positive impact on net exports and total reserves. Moreover, this research conducted robustness tests by replacing independent variables and conducting a sub-sample regression to ensure the reliability of the regression results. [ABSTRACT FROM AUTHOR]

Objectives: Overproduction of reactive species, notably reactive oxygen (ROS) and nitrogen (RNS) species, along with the failure of balancing effects of endogenous antioxidant defenses result in destruction of cellular structures, lipids, proteins, and genetic material, which lead to oxidative stress. Oxidative stress-induced neuronal apoptosis plays a pivotal role in pathogenesis of neurodegeneration. Antioxidants represent one of the medical choice strategies for protecting against this unbalanced oxidation-antioxidation status. Recently, natural compounds with neuroprotective potential that can scavenge free radicals and protect cells from oxidative damage have received extensive attention. Methods: In this review, we summarized the detailed research progress on the medicinal plants-derived natural compounds with potential anti-oxidation effects and their molecular mechanisms on modulating the neurotoxin (6-OHDA, H2O2, glutamate, Aβ)-induced oxidative stress and cell apoptosis. Results: The natural compounds that efficacious in modulating reactive species production and mitochondrial function include flavonoids, glucosides, alkaloids, polyphenols, lignans, coumarins, terpenoids, quinones and others. They decreased the neurotoxin-induced oxidative damage and apoptosis by (1) decreasing ROS/RNS generation, lipid peroxidation, caspase-3 and caspase-9 activities, LDH release, the ratio of Bax/Bcl-2, Ca2+ influx and cytochrome c release, (2) elevating MMP, and (3) restoring endogenous antioxidant enzymatic activities (CAT, GSH-Px, GSR, SOD). And they exerted neuroprotective effects against cell damages and apoptosis by modulating the oxidative cascades of different signaling pathways (Nrf2/HO-1, NF-κB, MAPKs, PI3K/Akt, GSK-3β) and preventing mitochondria-dependent apoptosis pathways. Discussion: The present work reviews the role of oxidative stress in neurodegeneration, highlighting the potential anti-oxidation effects of natural compounds as a promising approach to develop innovative neuroprotective strategy. [ABSTRACT FROM AUTHOR]

Thin-walled structures have been widely adopted in engineering projects because of the advantages of good load-bearing capacity, light weight and low cost. In this paper, a refined finite element method (FEM) based on the Carrera Unified Formula (CUF) is performed to analyze the free vibration of thin-walled beams with the variables cross-section, length and boundary. The low-dimensional FEM method could improve the efficiency of numerical analysis and reduce the time consumption. The one-dimensional (1D) CUF is employed in which the models are assumed to be a beam-like axis-oriented structures. In this case, the geometry of the thin-walled beam can be discretized as a limited number of 1D beam elements along the axis, while the Lagrange polynomial expansion may be used to approximate the displacement field on the cross-beam surface. Thus, FEM matrices and vectors can be written in terms of fundamental nuclei whose forms are independent of beam theories. The validity and capabilities of the method presented are examined in some numerical examples, and a comparative study is carried out between the method proposed and the three-dimensional element method with and without warping solutions. The results obtained by CUF 1D models are in close agreement with the reference solutions. In addition, it has been argued that the innovative approach presented in this paper can be used as a precise tool for structural analysis for complex cross-section thin-walled beams to reduce computational costs. [ABSTRACT FROM AUTHOR]

The current study attempts to adopt more comprehensive and rigorous methods to deconstruct and confirm the association between guilt and moral dilemma judgements, with the expectation of providing new insights for related research. A total of 170 college participants were employed in separate batches for the experiment, including 53 males and 117 females, ranging from 17 to 28 years old (M = 20.88, SD = 2.29). We first induced guilt in the subjects using recalling and writing tasks and then asked the participants to complete the moral dilemma judgement tasks. Results of the analysis using traditional methods showed no association between induced guilt and moral dilemma judgements. However, the results of the process dissociation analysis indicated that induced guilt is related to higher deontological inclination. Moreover, the CNI model analysis revealed that induced guilt has a stronger sensitivity to moral norms. Induced guilt was associated with a stronger sensitivity to moral norms, which is reflected in less violation and more compliance with moral norms. There was no direct relation between induced guilt and the sensitivity to consequences and a general preference for action in moral decision-making. What is already known about this topic: Previous findings on the relation of guilt in moral decision-making were not consistent. The traditional approach treats utilitarianism and deontology as bipolar opposites, which may further confound the relation between guilt and moral decision-making. Numerous studies imply that guilt increases other-oriented empathy and emotional concern for the victims. What this topic adds: Induced Guilt is associated with higher sensitivity to moral norms and will discipline one's behaviour to be more in line with ethical standards. Induced Guilt is unrelated to utilitarian decisions about the well-being of the majority and is not involved in the inhibition and activation of action. The current study used more comprehensive and rigorous methods to clarify the potential confounding factors. [ABSTRACT FROM AUTHOR]

There is a broad consensus that subduction of the Paleo-Pacific oceanic plate has caused extensive magmatism, lithospheric deformation, and metal mineralization in the eastern margin of the Eurasian continent during the Late Mesozoic. However, the onset and extent of subduction of the Paleo-Pacific Ocean, especially the timing of the transition in tectonic regime from the Paleo-Asian Ocean to Paleo-Pacific, and extent of the subduction of the Paleo-Pacific Ocean remain poorly constrained. To address these key issues, we present regional geological observations, zircon U–Pb dating, whole-rock geochemistry, and Hf isotopic compositions of the Jurassic intrusions at the northern margin of the North China Craton, with the aim of constraining their petrogenesis and the tectono-magmatic events related to subduction of the Paleo-Pacific Ocean. The geochronological and geochemical results indicate that these intrusions were emplaced between 177 and 155 Ma, with distinct geochemical features. The Huajianggou pluton (HJG), Tongjiatun pluton (TJT), and Haoguantun pluton (HGT) are characterized by high Al2O3 and Sr contents, and low MgO, TFe2O3, Y, Yb, and heavy rare earth elements (HREEs) contents, coupled with high Sr/Y values (34.10–94.36), showing adakitic affinities. Based on these geochemical characteristics, we suggest that these adakitic magmas (i.e. the HJG, TJT, and HGT plutons) were produced by partial melting of thickened lower crust in response to earlier subduction of the Paleo-Pacific oceanic plate beneath the northern margin of the North China Craton. In contrast, the Baijiagou pluton (BJG) and Sheshangou pluton (SSG) are high-K calc-alkaline rocks with low Sr/Y ratios (0.80–17.77), and they exhibit petrological and geochemical characteristics of I-type granites, indicating an origin from the lower crust, with variable degrees of fractional crystallization. In addition, the Bakeshu pluton (BKS) is mainly comprised of diorite that displays high SiO2, low MgO, Cr, and Ni contents, with Mg# of 39.8–42.9, indicating a lower crustal origin. Despite the range in ages of these intrusions, all the Jurassic calc-alkaline intrusions show typical geochemical characteristics of active continental margins, such as enrichment in large ion lithophile elements (LILEs) and light rare earth elements (LREEs), and depletion in high field strength elements (HFSEs). Combined with spatial-temporal variations of coeval magmatic rocks along the northern margin of the North China Craton, we suggest that the transition in tectonic regime from the Paleo-Asian Ocean to Paleo-Pacific Ocean was initiated in the Early Jurassic. These Jurassic intrusions formed in an active continental margin setting, related to westward subduction of the Paleo-Pacific oceanic plate. Importantly, the Early Jurassic subduction-related calc-alkaline magmatic rocks in northeast (NE) China constitute a NE-trending magmatic arc belt, which is best explained as continental magmatism triggered by the westward subduction of the Paleo-Pacific oceanic plate. [ABSTRACT FROM AUTHOR]

Sepsis-associated acute lung injury (ALI) is a clinically severe respiratory disorder and remains the leading cause of multiple organ failure and mortality. Herein, we used lipopolysaccharide (LPS) to generate sepsis-induced ALI and try to explore the role and mechanism of microRNA-92a-3p (miR-92a-3p) in this process. Mice were intravenously injected with miR-92a-3p agomir, antagomir and negative controls for 3 consecutive days and then were intratracheally instillated by LPS (5 mg/kg) for 12 h. To knock down the endogenous A-kinase anchoring protein 1 (AKAP1), mice were intratracheally injected with recombinant adenovirus carrying the short hairpin RNA targeting AKAP1 (shAkap1) at 1 week before LPS administration. miR-92a-3p level was significantly upregulated in the lungs by LPS injection. miR-92a-3p antagomir reduced LPS-induced intrapulmonary inflammation and oxidative stress, thereby preventing pulmonary injury and dysfunction. In contrast, miR-92a-3p agomir aggravated LPS-induced intrapulmonary inflammation, oxidative stress, pulmonary injury and dysfunction. Moreover, we reported that AKAP1 upregulation was required for the beneficial effects of miR-92a-3p antagomir, and that AKAP1 knockdown completely abolished the anti-inflammatory and antioxidant capacities of miR-92a-3p antagomir. Our data identify that miR-92a-3p modulates LPS-induced intrapulmonary inflammation, oxidative stress and ALI via AKAP1 in mice. [ABSTRACT FROM AUTHOR]

Ni-based single-atom catalysis (Ni-SAC) has been experimentally reported with superior performance in reducing CO2 to CO. However, due to the ambiguities in its structures, the active sites of Ni-SAC that are responsible for superior performance have not yet been resolved. This work investigates the CO2 reduction reaction (CO2RR) mechanism on Ni-SAC by carrying out quantum mechanics (QM) simulation to consider both solvation effects. After exploring multiple possible combinations of N, S, and C, we distinguish a Ni-SAC site with two C, one S, and one N, representing the best performance. The predicted formation energy is closely consistent with experimental onset potential. Our prediction also suggests further improvement by finely tuning the electronics state of metal sites by changing the SAC support. [ABSTRACT FROM AUTHOR]

Abstract A new dinuclear copper(II) complex, [Cu2L4] is obtained from the reaction of CuCl2⋅2H2O with a triazenido compound, 1-[(2-methoxy) phenyl]-3-[2-pyridine] triazene (HL), which is prepared by the reaction of o-anisidine anthranilate, sodium nitrite and 2-aminopyridine. Magnetic investigation shows that there is an antiferromagnetic exchange interaction between copper(II) ions. Electrochemical studies exhibit that [Cu2L4] can serve as catalyst for hydrogen generation both from acetic acid with a turnover frequency (TOF) of 48.95 moles of hydrogen per mole of catalyst per hour (mol H2/mol catalyst/h) at an overpotential (OP) of 941.6 mV, and a phosphate buffer (pH 7.0) with a TOF of 814.79 mol H2/mol catalyst/h at an OP of 836.7 mV. [ABSTRACT FROM AUTHOR]

In this paper, a redesigned approximate dynamic inversion (RADI) method is developed for a class of pure-feedback nonaffine-in-control nonlinear systems (PFNNSs). Recently, the approximate dynamic inversion (ADI)-based algorithms have been widely implemented for nonaffine-in-control nonlinear systems. To employ ADI-based methods, a fast dynamic subsystem has to be established to derive the explicit inversion of the nonaffine equation. However, the previous research on ADI rarely considers that the amplitude of actual input derived from the fast augmented subsystem can be extremely high, which maybe intolerable for practical systems. In this paper, we set up input saturation and view the difference between input with and without saturation as a perturbation. Then, an intermediate subsystem is constructed to compensate the influence of this perturbation by approximating its inversion. The exponential stability of the overall closed-loop system is ensured via singular perturbation theorem. Numerical examples are provided to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Soil–rock mixtures is a special engineering geological material and often used as a roadbed filler. Based on the orthogonal experimental method, a series of large-scale triaxial tests of soil–rock mixtures under the freeze–thaw cycle environment was designed with five factors including rock content, compaction degree, moisture content, number of freeze–thaw cycles and freezing temperature at four experimental levels, respectively. Then, the effect of each orthogonal experimental factor and the effect of the confining pressure on the statics mechanical characteristics of the soil–rock mixtures were statistically investigated by range and variance analysis. Research results showed that the static stress of the soil–rock mixtures is linearly positively correlated with the confining pressure; for different confining pressures, the most crucial factors to affect the static stress are different; for the shear strength, the most crucial factors to affect the cohesive force and friction angle are correspondingly number of freeze–thaw cycles and rock content. The study of the crucial influence factors at different confining pressures after freeze–thaw cycles can provide guidance for design and protection of soil–rock mixtures under different environment. [ABSTRACT FROM AUTHOR]

Architectural structures today are increasingly complex and structural health monitoring plays an important role in guaranteeing their safety. How to improve the reliability of deformation analysis is, thus, one of the key problems. This article combines laser-based measurement technology and the Carrera unified formulation (CUF) method to investigate the deformation of engineering structures. Within this article, we simulate architectural structures using the CUF geometric model, which is consistent with the results of the laser tracker experiment. We aimed at constructing an intelligent and efficient CUF model which can be applied extensively in the monitoring of various constructs, such as tunnels and bridges. The innovation of this article is that high-accuracy laser tracker technology is integrated with an effective CUF model to investigate the load-displacement relationship considering lateral displacement. [ABSTRACT FROM AUTHOR]

Freeform parameterizations to reproduce structure deformation are increasingly important topics in laser-scanner-based deformation analyses. High-accuracy assurance of free-form surface approximation is extremely critical for reliable deformation analysis. One main challenge in this field is the model selection. Improper model complexity could result in under-fitting the real object shape or overfitting data noises, and thus a failure of deformation analysis. A multi-sensor system could integrate advantages of different sensors and improve the quality of mission completed. This paper combines terrestrial laser scanning (TLS) and laser tracker (LT) technologies, to enhance high-accuracy surface modeling in deformation analysis. A surface-based B-spline approximation and a multi-sensor system are investigated, the latter of which focuses mainly on the combination of TLS and LT technologies. The innovation of this paper is that the surface-based B-spline approximation is validated and optimized with LT corner cube reflectors. Hypothesis testing is adopted to select the best parameter setting by judging most consistency of TLS and LT in various epochs. In the B-spline surface modeling, both instrumental and numerical uncertainties are considered. We use the instrumental uncertainty model based on intensity value, as well as numerical uncertainty based on adjustment theories. A sampling strategy is proposed to avoid data gaps and obtain even distributed data points. [ABSTRACT FROM AUTHOR]

This study investigates an AR (autoregressive)-filtered version of several conventional diagnostic tests for cross-sectional dependence in large mixed panels when both N and T are large, including the adjusted Lagrangian Multiplier test (LM), the cross-section dependence test (CD), and the Schott test. We show that conventional tests of cross-sectional dependence based on Pearson correlation coefficients could diverge if the components are not all I(0) processes and the modified tests possess the asymptotical normality property. The distinctive feature of these new tests is their ease of implementation, even though the exact time series properties of each component of a mixed panel are unknown or unobservable in practice. Simulations show that the AR-filtered version of the CD test (CDAR) performs well relative to the other testing procedures in the finite sample and computation time, especially for those cases with a large cross-sectional dimension. Given the good statistical properties of CDAR test, we also propose to use it as an early warning indicator for market risk or crisis. [ABSTRACT FROM AUTHOR]

This paper develops a fault compensation scheme for a class of Euler–Bernoulli beam-ODE cascade systems to deal with certain boundary input faults, using a model transform-based backstepping control design. A model transformation is introduced to convert the Euler–Bernoulli beam-ODE cascade system to a Schrödinger-ODE cascade system. The FTC law is designed to compensate boundary input faults for the Schrödinger-ODE cascade system by constructing a normal intermediate system and a new exponentially stable target system. The purposes of the two-step backstepping are to bring in a state feedback and to improve the system performance. The performance of the target system, intermediate system, and Schrödinger-ODE cascade system is analysed in the Riesz basis frame. The stability analysis of the original Euler–Bernoulli beam-ODE cascade system is further provided. Simulation results illustrate the effectiveness of the proposed fault compensation scheme. [ABSTRACT FROM AUTHOR]

4-Phenyl-3-thiosemicarbazide reacts with 2,3-butanedione to provide a new compound, diacetyl-bis(N4-phenyl-3-thiosemicarbazonato) (H2ATSP). In the presence of triethylamine (Et3N), the reaction of H2ATSP with NiCl2 affords a new nickel complex, diacetyl-bis(N4-phenyl-3-thiosemicarbazonato)nickle(II) (NiII-ATSP), a diamagnetic material, which has been characterized by physicochemical and spectroscopic methods. Studies exhibit that Ni-ATSP has good catalytic activities for both electrochemical and photochemical driven hydrogen evolution. Under an overpotential (OP) of 837.6 mV, 188.7 moles of hydrogen per mole of catalyst per hour (mol H2/mol catalyst/h) are afforded from an electrolysis of neutral water with Ni-ATSP. With blue light (λ = 469 nm) irradiation, together with CdS nanorods (CdS NRs) as a photosensitizer, and ascorbic acid (H2A) as a sacrificial electron donor, Ni-ATSP can catalyze hydrogen generation with a turnover number (TON) of 9554 moles H2 per mol of catalyst (mol of cat−1) during 50 h irradiation in a heterogeneous environment. [ABSTRACT FROM AUTHOR]

This paper addresses a fault accommodation issue for flexible hypersonic vehicles by the static output feedback. Firstly, a longitudinal dynamics for hypersonic vehicles is established in the ODE-beam cascade form and the distributed fault model is built. Next, a novel fault accommodation scheme is developed to achieve fault accommodation and vibration suppression. Such a control strategy is based on the control separation formulation: one component is for accommodating the distributed fault, another one is for the closed-loop stability. The input-to-state stability of the closed-loop system is analysed by using the direct Lyapunov method and bilinear matrix inequalities technique. Then, a new algorithm is provided to obtain the control gain matrices of the fault-tolerant control law. Finally, the simulation results are given to illustrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

This paper considers the fault-tolerant control (FTC) problem for switched systems described by linear hyperbolic partial differential equations with the process and boundary faults. The effect of faults is compensated by designing the desirable boundary control gain. Both the accumulative and dissipative characteristics of faults are considered, respectively. Several Lyapunov-based FTC schemes that depend on the system parameters and boundary conditions are proposed which guarantee the exponential stability of the non-switched hyperbolic systems. The new result is further extended to the switched linear hyperbolic systems where the boundary control gain of each mode and the switching law are designed comprehensively. It shows that the FTC goal can be achieved even if only some faulty modes are stabilizable. An air traffic flow example is taken to illustrate the theoretical results. [ABSTRACT FROM AUTHOR]