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Summary: This article investigates the issue of orbit coordination control for a class of multi‐spacecraft formation systems in presence of limited communication and external disturbance. To solve the limitation of communication sources, a dynamic event trigger (DET) mechanism is developed to reduce the communication frequency between the follower spacecrafts. Subsequently, we explore a robust DET mechanism‐based distributed self‐learning sliding mode control design, in which a variable learning intensity‐based iterative learning algorithm is designed to approximate and compensate space perturbation. This approach can guarantee an event triggering sequence without Zeno phenomenon and accurate coordination control for formation configuration simultaneously. Compared with the traditional event‐triggered control and other state‐of‐the‐art approaches, the distributed DET control scheme achieves higher control accuracy of formation configuration meanwhile requires less communication resource. Finally, a series of numerical simulations demonstrate the feasibility and superiority of the event triggered control method. [ABSTRACT FROM AUTHOR]

This paper studies the issue of learning radial basis function neural network (RBFNN)-based robust reconfigurable fault-tolerant configuration control for spacecraft formation flying (SFF) systems subject to thruster faults and space perturbations. To robustly reconstruct thruster faults, a novel learning RBFNN estimator is innovatively explored, in which the P-type iterative learning algorithm is utilized to online update the weight matrix of the RBFNN model and the H∞ control technique is adopted to attenuate the effect of space perturbations. Further, a learning RBFNN output-feedback fault-tolerant control (FTC) method is developed for spacecraft formation configuration maintenance with high accuracy, and the learning RBFNN algorithm is used to update and compensate the synthesized perturbation. Finally, a numerical example is simulated to verify the presented learning RBFNN-based spacecraft formation FTC approach is feasible and superior. [ABSTRACT FROM AUTHOR]

Two α-pyrone analogs were isolated from the endophytic fungus Diaporthe sp. CB10100, which is derived from the medicinal plant Sinomenium acutum. These analogs included a new compound, diaporpyrone F (3), and a known compound, diaporpyrone D (4). The structure of 3 was identified by a comprehensive examination of HRESIMS, 1D and 2D NMR spectroscopic data. Bioinformatics analysis revealed that biosynthetic gene clusters for α-pyrone analogs are common in fungi of Diaporthe species. The in vitro α-glucosidase inhibitory activity and antibacterial assay of 4 revealed that it has a 46.40% inhibitory effect on α-glucosidase at 800 μM, while no antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA), Mycolicibacterium (Mycobacterium) smegmatis or Klebsiella pneumoniae at 64 μg/mL. Molecular docking and molecular dynamics simulations of 4 with α-glucosidase further suggested that the compounds are potential α-glucosidase inhibitors. Therefore, α-pyrone analogs can be used as lead compounds for α-glucosidase inhibitors in more in-depth studies. [ABSTRACT FROM AUTHOR]

As cast and extruded 6063 aluminum alloy containing rare earth Y was prepared and anodized. The morphology of the anodic oxide film of the alloy was studied and its effect on the hardness and corrosion resistance of the alloy was analyzed. The results showed that compared with ordinary 6063 aluminum alloy, the oxide film of 6063 aluminum alloy modified by rare earth Y has dense surface, no defects and is closely combined with the matrix, and the corresponding surface roughness Sa value is the smallest. The chemical composition of anodic oxide film is mainly alumina, which can significantly improve the surface microhardness of the alloy. After coating, the self- corrosion potential of extruded rare earth Y modified 6063 aluminum alloy is corrected, the self-corrosion current deny is small, the total impedance value is high, and it shows the characteristics of capacitive arc resistance n high frequency region, and the corrosion resistance is better. [ABSTRACT FROM AUTHOR]

Objectives: A genome sequence of a threatened species can provide valuable genetic information that is important for improving the conservation strategies. The white-eared night heron (Gorsachius magnificus) is an endangered and poorly known ardeid bird. In order to support future studies on conservation genetics and evolutionary adaptation of this species, we have reported a de novo assembled and annotated whole-genome sequence of the G. magnificus. Data description: The final draft genome assembly of the G. magnificus was 1.19 Gb in size, with a contig N50 of 187.69 kb and a scaffold N50 of 7,338.28 kb. According to BUSCO analysis, the genome assembly contained 97.49% of the 8,338 genes in the Aves (odb10) dataset. Approximately 10.52% of the genome assembly was composed of repetitive sequences. A total of 14,613 protein-coding genes were predicted in the genome assembly, with functional annotations available for 14,611 genes. The genome assembly exhibited a heterozygosity rate of 0.49 heterozygosity per kilobase pair. This draft genome of G. magnificus provides valuable genomic resources for future studies on conservation and evolution. [ABSTRACT FROM AUTHOR]

Background: Improving imaging speed has always been the focus of research in CT technology, which is related to the radiation dose and imaging quality of moving organs, including heart and blood vessels. However, it is difficult to achieve further improvement by increasing the rotation speed of the gantry due to its structural strength limitation. Differing from the conventional CTs, the static CT employs dozens of ray sources to acquire projection data from different angular ranges, and each source only needs to be rotated in a small range to finish a full 360° scan, thus greatly increasing the scanning speed. Purpose: As sources of static CT need to be evenly distributed over 360°, the sources and detectors have to be arranged on two parallel rings independently. Such a geometry can be considered as a special case of CT systems with a significantly large cone angle, that is, a part of the detector is missing in the vicinity of the mid‐plane. Due to restriction of upper and lower bounds of the cone angle of the static CT, there are uneven projection data varying in each portion of the reconstruction volume, the conventional analytical or iterative reconstruction methods may introduce artifacts in the reconstructed outcomes. Methods: Following the weighting approach extended FDK (xFDK) by Grimmer et al., we propose an improved bilateral xFDK algorithm (bixFDK), which focuses on the reconstruction of the expanded volume. With the same philosophy as xFDK in terms of weighting function design, bixFDK takes the longitudinal offset of the detector with respect to the source into consideration, making our method applicable to a wide range of CT geometries, especially for the static CT. Based on the proposed bixFDK, a new iterative scheme bixFDK‐IR is also constructed to extend the applications to a wide range of scan protocols such as sparse‐view scan. Results: The proposed method has been validated with the simulated phantom data and the actual clinical data of the static CT, and demonstrates that it can ensure good image quality and enlarge the reconstruction volume in z‐direction of the static CT. Conclusions: The bixFDK algorithm is an ideal reconstruction approach for static CT geometry, and the iterative scheme of bixFDK‐IR is applicable to a wide range of CT geometries and scan protocols, thus providing a wide range of application scenarios. [ABSTRACT FROM AUTHOR]

Purpose: The maintenance of stable blood glucose levels in gestational diabetes patients depends on their ability to make scientific decisions. Decision-making ability is influenced by factors such as preferences, knowledge acquisition, and risk perceptions. At present, problems such as irrational dietary structure, difficulties in decision-making, and poor adherence still exist in clinical practice. The key to guiding gestational diabetes patients in developing their scientific decision-making abilities lies in identifying the weak key points that affect their decision-making abilities. There is a lack of validated tools to assess these patients' perceptions of dietary intake. In this study, we aimed to develop and validate the Dietary Intake Perceived Motivation Questionnaire for Patients with Gestational Diabetes Mellitus with the purpose of accurately identifying the obstacles encountered by gestational diabetes mellitus patients in the development of their scientific decision-making abilities.Patients and Methods: In this study, 304 individuals with gestational diabetes were recruited from a public hospital in Wuxi, China. The questionnaire was developed in 3 stages, consisting of questionnaire development, a pilot study, and a formal test, and the validity and reliability of the questionnaire were tested and confirmed. The content validity index and exploratory factor analysis were completed by expert correspondence to indicate the validity of the content and structure. In addition, Cronbach's α was used to evaluate the internal consistency of each item of the questionnaire, and Spearman-Brown analysis was used to analyze the split-half reliability. In addition to the questionnaire, the study participants were asked to complete a general information questionnaire that included items on various demographic factors such as age, week of gestation, and mode of conception.Results: The questionnaire was validated through principal component analysis, resulting in a 31-item questionnaire named the Dietary Intake Perceived Motivation Questionnaire for Patients with Gestational Diabetes Mellitus. This questionnaire explained 86.267% of the variance and demonstrated good internal consistency (Cronbach's α= 0.929).Conclusion: Our study determined that the questionnaire serves as a valuable tool in evaluating the motivation behind dietary intake in gestational diabetes patients. [ABSTRACT FROM AUTHOR]

Background: Gaze is the primary way for pedestrians to obtain clues from traffic scenes before making decisions. Therefore, understanding pedestrian gaze pattern is vital for traffic safety in general and for the design of autonomous vehicles. Methods: In this study, participants made road-crossing decisions in a naturalistic traffic scene, with an eye-tracker recording their gaze behaviors. We manually encoded the recorded videos with 14,898 fixations, and then analyzed the gaze pattern at three levels from general to specific: gaze towards overall scenes, gaze towards vehicles and gaze towards components of vehicles. Findings: At the first level, our findings indicate that frequent fixations began to appear at the distance of 100 m and peaked around 5–30 m away from pedestrians. Transversely pedestrians mainly gazed at the two lanes adjacent to themselves. Pedestrians allocated 53% gaze duration to motor vehicles. For a specific vehicle, which is the second level, the gaze duration varied with vehicles' attributes such as distances, sizes, and types. Finally, at the third level, we discovered that pedestrians' gaze duration on different vehicle components varied with the longitudinal distance. As vehicles approach, the main area of fixation expanded from the near side headlight to the whole front and near side, and finally shift to the near side of a vehicle. Implications: The distribution of fixations in space and vehicle components before pedestrian crossing can provide fundamental information for understanding and modeling of pedestrian's road-crossing behaviors. In practice, our findings can guide the timing and position of information displays on autonomous vehicles to facilitate friendly interaction with pedestrians. [ABSTRACT FROM AUTHOR]

Background: The goal was to investigate the feasibility of the registration generative adversarial network (RegGAN) model in image conversion for performing adaptive radiation therapy on the head and neck and its stability under different cone beam computed tomography (CBCT) models. Methods: A total of 100 CBCT and CT images of patients diagnosed with head and neck tumors were utilized for the training phase, whereas the testing phase involved 40 distinct patients obtained from four different linear accelerators. The RegGAN model was trained and tested to evaluate its performance. The generated synthetic CT (sCT) image quality was compared to that of planning CT (pCT) images by employing metrics such as the mean absolute error (MAE), peak signal-to-noise ratio (PSNR), and structural similarity index measure (SSIM). Moreover, the radiation therapy plan was uniformly applied to both the sCT and pCT images to analyze the planning target volume (PTV) dose statistics and calculate the dose difference rate, reinforcing the model's accuracy. Results: The generated sCT images had good image quality, and no significant differences were observed among the different CBCT modes. The conversion effect achieved for Synergy was the best, and the MAE decreased from 231.3 ± 55.48 to 45.63 ± 10.78; the PSNR increased from 19.40 ± 1.46 to 26.75 ± 1.32; the SSIM increased from 0.82 ± 0.02 to 0.85 ± 0.04. The quality improvement effect achieved for sCT image synthesis based on RegGAN was obvious, and no significant sCT synthesis differences were observed among different accelerators. Conclusion: The sCT images generated by the RegGAN model had high image quality, and the RegGAN model exhibited a strong generalization ability across different accelerators, enabling its outputs to be used as reference images for performing adaptive radiation therapy on the head and neck. [ABSTRACT FROM AUTHOR]

Background: This paper evaluated the clinical utility of massively parallel sequencing-based non-invasive prenatal testing (NIPT) for detecting trisomy 21 (T21), T18, T13, sex chromosome aneuploidies (SCA), and rare chromosome aneuploidies (RCA) among the data collected by a clinical laboratory in southern China. Methods: In a 3-year period between January 2017 and December 2019, over 40,000 pregnant women underwent NIPT clinical screening test for fetal T21, T18, T13, SCA, and RCA in our laboratory. NIPT samples were processed using the NextSeq CN500 platform. The positive results were confirmed by karyotyping, and chromosomal microarray analysis (CMA) or copy number variants (CNV) sequencing. Details of the pregnancy outcomes were collected via telephone interview. Results: NIPT results were available for 41,819 cases; 691 positive cases were reported. The overall sensitivity for detection of T21, T18, T13, SCA, and RCA was 99.21, 100.00, 100.00, 98.55, and 100.00%, and the specificity was 99.95, 99.94, 99.98, 99.69, and 99.92%, respectively. The positive predictive values (PPVs) for detection of T21, T18, T13, SCA, and RCA were 85.62, 45.24, 40.00, 34.17, and 13.51%, respectively, and those for detection of 45,X, 47,XXY, 47,XXX, 47,XYY, and 46,XY(delX) 20.00, 59.18, 28.95, 61.54, and 25.00%, respectively. Regarding pregnancy outcomes, 92.38% of the pregnancies with confirmed aneuploidies were terminated, and 91.20% of those identified as having a false-positive result were carried to term. Among 252 unconfirmed cases, 24.60% of the pregnancies were terminated and 38.10% carried to term, while 37.30% declined interview. Conclusions: NIPT is widely used to screen fetal aneuploidies based on its high sensitivity and specificity. However, in this study, the PPVs of NIPT in terms of detecting T18, T13, XO, XXX and RCA were < 50%. In addition, more than one-third of NIPT-positive women did not accept invasive prenatal diagnosis. Confirmatory diagnosis is strongly recommended for women with positive NIPT outcomes before any further decision is made. [ABSTRACT FROM AUTHOR]

Ultra‐low molecular weight (ULMW) CO2‐polyols with well‐defined hydroxyl end groups represent useful soft segments for the preparation of high‐performance polyurethane foams. However, owing to the poor proton tolerance of catalysts towards CO2/epoxide telomerization, it remains challenging to synthesize ULMW yet colorless CO2‐polyols. Herein, we propose an immobilization strategy of constructing supported catalysts by chemical anchoring of aluminum porphyrin on Merrifield resin. The resulting supported catalyst displays both extremely high proton tolerance (≈8000 times the equivalents of metal centers) and independence of cocatalyst, affording CO2‐polyols with ULMW (580 g mol−1) and high polymer selectivity (>99 %). Moreover, the ULMW CO2‐polyols with various architectures (tri‐, quadra‐, and hexa‐arm) can be obtained, suggesting the wide proton universality of supported catalysts. Notably, benefiting from the heterogeneous nature of the supported catalyst, colorless products can be facilely achieved by simple filtration. The present strategy provides a platform for the synthesis of colorless ULMW polyols derived from not only CO2/epoxides, but also lactone, anhydrides etc. or their combinations. [ABSTRACT FROM AUTHOR]

Ultra‐low molecular weight (ULMW) CO2‐polyols with well‐defined hydroxyl end groups represent useful soft segments for the preparation of high‐performance polyurethane foams. However, owing to the poor proton tolerance of catalysts towards CO2/epoxide telomerization, it remains challenging to synthesize ULMW yet colorless CO2‐polyols. Herein, we propose an immobilization strategy of constructing supported catalysts by chemical anchoring of aluminum porphyrin on Merrifield resin. The resulting supported catalyst displays both extremely high proton tolerance (≈8000 times the equivalents of metal centers) and independence of cocatalyst, affording CO2‐polyols with ULMW (580 g mol−1) and high polymer selectivity (>99 %). Moreover, the ULMW CO2‐polyols with various architectures (tri‐, quadra‐, and hexa‐arm) can be obtained, suggesting the wide proton universality of supported catalysts. Notably, benefiting from the heterogeneous nature of the supported catalyst, colorless products can be facilely achieved by simple filtration. The present strategy provides a platform for the synthesis of colorless ULMW polyols derived from not only CO2/epoxides, but also lactone, anhydrides etc. or their combinations. [ABSTRACT FROM AUTHOR]

This paper investigates the attitude fault-tolerant stabilization problem for a spacecraft subjected to its actuator effectiveness loss, inertia uncertainties and space disturbances. A novel Iterative Learning Sliding Mode Observer (ILSMO) is proposed to reconstruct the actuator effectiveness factors robustly and accurately by combining the P-type iterative learning algorithm with the sliding mode approach. Based on the reconstructed fault signals, an Iterative Learning Sliding Mode Controller (ILSMC) is designed to guarantee the closed-loop spacecraft attitude fault-tolerant stabilization by compensating for its lumped disturbance. The ILSMO and ILSMC stabilities are guaranteed using the Lyapunov direct approach, respectively. Finally, the numerical simulation results show that the proposed ILSMO-ILSMC-based spacecraft attitude fault-tolerant stabilization method is effective and superior. [ABSTRACT FROM AUTHOR]

By screening a series of 3d/4d/5d transition metal (TM) atoms, a total of twelve graphene-based single atom catalysts (SAC) with TMO 3 and TMO 4 units can exhibit the excellent OER performance with extremely low overpotential (0.33 ∼ 0.59 V), in which the V/Nb/Ta atoms in VB group and Ru/Co/Rh/Ir atoms in VIII group can serve as the active sites. The self-optimization process of TM-sites can be responsible for the high OER catalytic activity for most of these SAC systems. [Display omitted] High-throughput DFT calculations are performed to explore the oxygen evolution reaction (OER) catalytic activity of a series of 2D graphene-based systems with TMO 3 or TMO 4 functional units. By screening the 3d/4d/5d transition metal (TM) atoms, a total of twelve TMO 3 @G or TMO 4 @G systems had extremely low overpotential of 0.33 ∼ 0.59 V, in which the V/Nb/Ta atom in VB group and Ru/Co/Rh/Ir atom in VIII group served as the active sites. The mechanism analysis reveals that the filling of outer electrons of TM atom can play an important role in determining the overpotential value by affecting the ΔG O* value as an effective descriptor. Especially, in addition to the general situation of OER on the clean surface of the systems containing the Rh/Ir metal centers, the self-optimization process of TM-sites was carried out, and it made most of these single-atom catalysts (SAC) systems to have high OER catalytic activity. All these fascinating findings can contribute to an in-depth understanding of the OER catalytic activity and mechanism of the excellent graphene-based SAC systems. This work will facilitate the design and implementation of non-precious and highly efficient OER catalysts in the near future. [ABSTRACT FROM AUTHOR]

Introduction: Objective observational studies have shown that basal metabolic rate (BMR) decreases in patients with Alzheimer's disease (AD), but the causal relationship between BMR and AD has not been established. We determined the causal relationship between BMR and AD by two-way Mendelian randomization (MR) and investigated the impact of factors associated with BMR on AD. Methods: We obtained BMR (n = 454,874) and AD from a large genome-wide association study (GWAS) database (21,982 patients with AD, 41,944 controls). The causal relationship between AD and BMR was investigated using two-way MR. Additionally, we identified the causal relationship between AD and factors related with BMR, hyperthyroidism (hy/thy) and type 2 diabetes (T2D), height and weight. Results: BMR had a causal relationship with AD [451 single nucleotide polymorphisms (SNPs), odds ratio (OR) 0.749, 95% confidence intervals (CIs) 0.663–0.858, P = 2.40E-03]. There was no causal relationship between hy/thy or T2D and AD (P > 0.05). The bidirectional MR showed that there was also a causal relationship between AD and BMR (OR 0.992, Cls 0.987–0.997, NSNPs18, P = 1.50E−03). BMR, height and weight have a protective effect on AD. Based on MVMR analysis, we found that genetically determined height and weight may be adjusted by BMR to have a causal effect on AD, not height and weight themselves. Conclusion: Our study showed that higher BMR reduced the risk of AD, and patients with AD had a lower BMR. Because of a positive correlation with BMR, height and weight may have a protective effect on AD. The two metabolism-related diseases, hy/thy and T2D, had no causal relationship with AD. [ABSTRACT FROM AUTHOR]

Porcine interferon α (poIFN-α) is a crucial cytokine that can prevent and treat viral infections. Seventeen functional porcine IFN-α subtypes were found in the porcine genome. In this study, multiple sequence alignment was performed to analyze IFN-α protein structure and function. Phylogenetic tree analysis of the poIFN gene family defined the evolutionary relationship of various subtypes. PoIFN-αs, including poIFN-α1–17, were expressed in an Escherichia coli expression system. The antiviral activities of these IFN-α proteins against vesicular stomatitis virus (VSV) and pseudorabies virus (PRV) were examined in PK-15 cells. We found that the antiviral activity of different poIFN-α molecules greatly differed as follows: the poIFN-α14 and 17 subtypes had the greatest antiviral activities against VSV and PRV in PK-15 cells, poIFN-α1, 2, 3, and 8 exhibited lower biological activities, and poIFN-α4, 5, 6, 7, 9, 10, 11, 12, 13, and 16 had minimal or no effect in the tested target cell‒virus systems. Moreover, our studies demonstrated that the antiviral activity of IFN-α was positively correlated with the induction of IFN-stimulated genes, such as 2′–5′ oligoadenylate synthetase 1 (OSA1), interferon-stimulated gene 15 (ISG15), myxoma resistance protein 1 (Mx1), and protein kinase R (PKR). Thus, our experimental results provide important information about the antiviral functions and mechanism of poIFN-α. [ABSTRACT FROM AUTHOR]

Measuring the thermal shock crack growth process is crucial for revealing ceramic materials and structures' thermal shock failure mechanisms and evaluating their reliability. We used a self-made water quenching system to conduct thermal shock tests on alumina and zirconia ceramics. The thermal shock process was recorded by high-speed digital image correlation (DIC) during the test. The process of thermal shock crack initiation and propagation in two kinds of ceramics was determined by analyzing the speckle image change on the sample's surface. It is found that the crack growth rate of alumina is faster than that of zirconia, which is caused by different material parameters. This paper presents an in-situ measurement method for the initiation and propagation of thermal shock cracking in ceramic materials. It can provide a measurement method to identify and predict the thermal shock damage of ceramic components. [ABSTRACT FROM AUTHOR]

Over three years have passed since the COVID-19 pandemic started. The dangerousness and impact of COVID-19 should definitely not be ignored or underestimated. Other than the symptoms of acute infection, the long-term symptoms associated with SARS-CoV-2 infection, which are referred to here as "sequelae of long COVID (LC)", are also a conspicuous global public health concern. Although such sequelae were well-documented, the understanding of and insights regarding LC-related sequelae remain inadequate due to the limitations of previous studies (the follow-up, methodological flaws, heterogeneity among studies, etc.). Notably, robust evidence regarding diagnosis and treatment of certain LC sequelae remain insufficient and has been a stumbling block to better management of these patients. This awkward situation motivated us to conduct this review. Here, we comprehensively reviewed the updated information, particularly focusing on clinical issues. We attempt to provide the latest information regarding LC-related sequelae by systematically reviewing the involvement of main organ systems. We also propose paths for future exploration based on available knowledge and the authors' clinical experience. We believe that these take-home messages will be helpful to gain insights into LC and ultimately benefit clinical practice in treating LC-related sequelae. [ABSTRACT FROM AUTHOR]

A Ti/β-TCP composite porous scaffold with a hierarchical pore structure composed of 3D printed interconnected macroscopic pores and sintered microscopic pores was prepared by direct ink writing (DIW) 3D printing technology. This method can control the extrusion of composite ink at room temperature and produce a 3D scaffold using layer-by-layer deposition. We studied the effects of the β-TCP powder particle size, β-TCP/Ti powder ratio and solid loading on the rheological properties of the ink and optimised the DIW printing process parameters. After sintering, the compressive strength and elastic modulus of the composite scaffold reached 45 MPa and 1 GPa, which is close to the strength of human cancellous bone. The cell culture experiment confirmed that the composite scaffold had better biological properties than the pure titanium scaffold. The composite scaffold has satisfactory mechanical and biological properties, meeting the requirements for orthopaedic implants. [ABSTRACT FROM AUTHOR]

A combined fourth-order (2 + 1)-dimensional nonlinear partial differential equation which contains four fourth-order nonlinear terms and all second-order linear terms is formulated. This equation covers three generalized KP, Hirota–Satsuma–Ito, and Calogero–Bogoyavlenskii–Schiff equations as examples, which have physical applications in the study of various nonlinear phenomena in nature. In terms of some settings of the coefficients, a class of lump solutions is constructed by the Hirota bilinear method and the solutions are calculated through the symbolic computation system of Maple. Meanwhile, the relation between the coefficients and the solution is explored. Two special lump solutions are generated by taking proper values for the involved coefficients and parameters, and their dynamic behaviors are studied, as illustrative examples. The primary advantage of the Hirota bilinear method is to transform a nonlinear equation into a bilinear one so that the targeted equation can be easily studied. [ABSTRACT FROM AUTHOR]

Under DFT calculations, a systematic investigation is carried out to explore the structures and oxygen evolution reaction (OER) catalytic activities of a series of 2D single-atom catalyst (SAC) systems, which are constructed by doping the transition metal (TM) atoms in group VIII into the cavities of rigid phthalocyanine carbide (pc-C3N2). We can find that when Co, Rh, Ir and Ru atoms are doped in the small or large cavities of a pc-C3N2 monolayer, they can be used as high-activity centers of OER. All these four new TM@C3N2 nanostructures can exhibit very low overpotential values in the range of 0.33~0.48 V, even smaller than the state-of-the-art IrO2 (0.56 V), which indicates considerably high OER catalytic activity. In particular, the Rh@C3N2 system can show the best OER performance, given that doped Rh atoms can uniformly serve as high-OER-active centers, regardless of the size of cavity. In addition, a detailed mechanism analysis was carried out. It is found that in these doped pc-C3N2 systems, the number of outer electrons, the periodic number of doped TM atoms and the size of the embedded cavity can be considered the key factors affecting the OER catalytic activity, and excellent OER catalytic performance can be achieved through their effective cooperation. These fascinating findings can be advantageous for realizing low-cost and high-performance SAC catalysts for OER in the near future. [ABSTRACT FROM AUTHOR]

Background: Gaze is the primary way for pedestrians to obtain clues from traffic scenes before making decisions. Therefore, understanding pedestrian gaze pattern is vital for traffic safety in general and for the design of autonomous vehicles. Methods: In this study, participants made road-crossing decisions in a naturalistic traffic scene, with an eye-tracker recording their gaze behaviors. We manually encoded the recorded videos with 14,898 fixations, and then analyzed the gaze pattern at three levels from general to specific: gaze towards overall scenes, gaze towards vehicles and gaze towards components of vehicles. Findings: At the first level, our findings indicate that frequent fixations began to appear at the distance of 100 m and peaked around 5–30 m away from pedestrians. Transversely pedestrians mainly gazed at the two lanes adjacent to themselves. Pedestrians allocated 53% gaze duration to motor vehicles. For a specific vehicle, which is the second level, the gaze duration varied with vehicles' attributes such as distances, sizes, and types. Finally, at the third level, we discovered that pedestrians' gaze duration on different vehicle components varied with the longitudinal distance. As vehicles approach, the main area of fixation expanded from the near side headlight to the whole front and near side, and finally shift to the near side of a vehicle. Implications: The distribution of fixations in space and vehicle components before pedestrian crossing can provide fundamental information for understanding and modeling of pedestrian's road-crossing behaviors. In practice, our findings can guide the timing and position of information displays on autonomous vehicles to facilitate friendly interaction with pedestrians. [ABSTRACT FROM AUTHOR]

Based on alumina ceramics, we employ the phase‐field method to study the effects of thermal conductivity, specific heat, density, thermal expansion coefficient, Young's modulus, and fracture toughness on thermal shock cracks. The results show that increasing thermal conductivity and fracture toughness will reduce thermal shock damage. That is, the long crack length becomes shorter, or the crack density becomes smaller. However, increasing the thermal expansion coefficient and Young's modulus will increase thermal shock damage. It is consistent with the previous thermal shock theory. The effect of material parameters on crack propagation speed was also considered. In addition, we carried out a thermal shock test of the zirconia. The results of the phase‐field calculation are the same as the thermal shock results of the zirconia. This paper verifies that the phase‐field method is suitable for simulating thermal shock cracks in other ceramics. [ABSTRACT FROM AUTHOR]

This article presents a finite-time prescribed performance (FTPP) control approach based on a learning Chebyshev neural network (LCNN) for spacecraft attitude tracking with modeling uncertainties, actuator faults, and external disturbances. An FTPP function is designed to specify the desired accuracy boundary and finite-time convergence. Further, an FTPP-based learning sliding mode controller (LSMC) is constructed, where the lumped disturbance is approximated and compensated via a novel LCNN model. Unlike conventional adaptive CNN models, the LCNN model employs an iterative learning mechanism for adjusting the weights of the CNN model, reducing computing costs. The FTPP-based LSMC approach is presented with a detailed stability analysis. The proposed method offers a broad range of applications with the FTPP criteria satisfied. A series of simulations are performed to verify the validity and applicability of the proposed approach. [ABSTRACT FROM AUTHOR]

Background: Recent studies have shown that bone marrow stromal cell-derived exosomes (BMSC-Exos) can be used for tissue repair. However, whether the BMSC-Exos can promote tendon-bone healing after anterior cruciate ligament reconstruction (ACLR) is still unclear. In this study, we observed in vivo and in vitro the effect of rat BMSC-Exos on tendon-bone healing after ACLR and its possible mechanism. Methods: Highly expressed miRNAs in rat BMSC-Exos were selected by bioinformatics and verified in vitro. The effect of overexpressed miRNA in BMSC-Exos on M2 macrophage polarization was observed. A rat model of ACLR was established. The experimental components were divided into three groups: the control group, the BMSC-Exos group, and the BMSC-Exos with miR-23a-3p overexpression (BMSC-Exos mimic) group. Biomechanical tests, micro-CT, and histological staining were performed for analysis. Results: Bioinformatics analysis showed that miR-23a-3p was highly expressed in rat BMSC-Exos and could target interferon regulatory factor 1 (IRF1, a crucial regulator in M1 macrophage polarization). In vitro, compared with the control group or the BMSC-Exos group, the BMSC-Exos mimic more significantly promoted the polarization of macrophages from M1 to M2. In vivo, at 2 weeks, the number of M2 macrophages in the early local stage of ACLR was significantly increased in the BMSC-Exos mimic group; at 4 and 8 weeks, compared with the control group or the BMSC-Exos group, the bone tunnels of the tibia and femur sides of the rats in the BMSC-Exos mimic group were significantly smaller, the interface between the graft and the bone was narrowed, the bone volume/total volume ratio (BV/TV) increased, the collagen type II alpha 1 level increased, and the mechanical strength increased. Conclusions: BMSC-Exos promoted M1 macrophage to M2 macrophage polarization via miR-23a-3p, reduced the early inflammatory reaction at the tendon-bone interface, and promoted early healing after ACLR. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the efficacy of the double‐row and double‐pulley technique in treating anterior shoulder glenoid fracture (Ideberg type Ia) using shoulder arthroscopy. Methods: Thirty‐six patients with Ideberg type Ia admitted from March 1, 2017, to March 1, 2020, were retrospectively reviewed. Data of the patients' history included age, sex, side of the affected arm, the mean time from injury to surgery, the surgical duration, the average blood loss, and the average total duration of hospital stay. The double‐row and double‐pulley technique was used to repair the scapular glenoid fracture under arthroscopy. Computed tomography (CT) was used to evaluate fracture healing after surgery. The American Shoulder and Elbow Surgeons (ASES) score, the University of California at Los Angeles (UCLA) shoulder joint scoring system, and the Constant–Murley shoulder function score were used to assess the function of the affected shoulder. Results: The surgical duration was 90–150 min, with a mean of 127 min. The average blood loss was 90 mL (range, 60–120 mL), and the average total duration of hospital stay was 9.2 days (range, 3 to 14 days). At 9 months after surgery, the CT results showed that all fractures healed, and all patients returned to their previous levels of activity and regained an excellent range of motion. The visual analog scale (VAS) score was 7.55 ± 1.32 before surgery, and the VAS score significantly decreased to 1.24 ± 0.72 at 12 months after the operation (p < 0.05). The Constant, ASES, and UCLA shoulder function scores were 44.38 ± 2.16, 43.47 ± 12.76, and 21.80 ± 1.16 before the surgery, respectively, which improved to 93.52 ± 2.82, 91.34 ± 8.28, and 33.24 ± 1.64, respectively, in the following 12 months. One patient experienced fat liquefaction. However, no cases of deep venous thrombosis, iatrogenic neurovascular compromise, wound infection, or neurovascular injury were identified. Conclusion: The double‐row and double‐pulley technique for treating Ideberg type Ia under shoulder arthroscopy has minor surgical trauma, reliable fracture reduction and fixation, less postoperative pain, and fewer postoperative complications and significantly improves the patient's shoulder joint function. [ABSTRACT FROM AUTHOR]

Data envelopment analysis (DEA) is widely used to evaluate the performance of a group of homogeneous decision making units (DMUs). Considering the uncertainty, interval DEA has been introduced to fit into more situations. In this paper, an interval efficiency method based on slacks-based measure is proposed to solve the uncertain problems in DEA. Firstly, the maximum and minimum efficiency values of the evaluated DMU are calculated by the furthest and closest distance from the evaluated DMU to the projection points on the Pareto-efficient frontier, respectively. Then, the AHP method is used for the full ranking of DMUs. The paper uses the pairwise comparison relationship between each pair of DMUs to construct the interval multiplicative preference relations (IMPRs) matrix. If the matrix does not meet the consistency condition, a method to obtain consistency IMPRs is introduced. According to the consistency judgment matrix, the full ranking of DMUs can be obtained. Finally, we apply our method to the performance evaluation of 12 tourist hotels in Taipei in 2019. [ABSTRACT FROM AUTHOR]

The full-energy peak efficiency allow radioactivity determination in gamma-ray spectrometry. In the determination of the full-energy efficiency, numerical calculation method has been widely used because of its accessibility, stability, and low computational cost. The current study presents a new direct numerical method that is based on the determining of the total efficiency and the escape efficiency. The method provides a detailed description of the generation and escape of secondary photons from the sensitive volume. It is applicable to any source-detector geometry and also considers the self-attenuation of the source matrix and the attenuation caused by absorber layers between the source and the sensitive volume. The results of comparing the new numerical method with experimental measurement for the point source test model demonstrate relative errors within −2.73∼5.57 %, indicating the high reliability of this new method for sourceless efficiency calibration. [ABSTRACT FROM AUTHOR]

Identifying the pulse shape is a crucial step in detecting the contamination of surfaces by α/β radioactive isotopes. In this study, the authors propose a self-adaptive method to identify the pulse shape by applying the Gaussian mixture model and the constant-fraction timing algorithm to a ZnS(Ag) and plastic scintillator to improve its accuracy of detection of low-energy particles, and realize automatic calibration to reduce the operational difficulty of the process and improve its stability. The proposed method comprises a feature extraction algorithm running on an FPGA as well as a classifier and a training machine running on an embedded processor. The feature extraction algorithm forms the core of the proposed method, is independent of the amplitude of the pulse signal, and can extract important information (pulse width and rise time) from the pulse signals to simplify the probabilistic model. The proposed method was tested on a ZnS(Ag) plastic scintillator, and the results showed that the feature extraction algorithm was more robust against errors in the amplitude of the pulse signal than the method that involves using a fixed threshold. The error in its results compared with those of measurements could be controlled to within 4% during mixed radiation field tests involving a single source of radiation. Moreover, we have deployed a complete program to train the model on the platform to support onboard model training and self-adaptive parameter estimation without requiring human intervention. • This paper presents a method for discriminating α/β particles in ZnS(Ag) and plastic scintillator. • Using the constant-fraction timing algorithm has enhanced low-energy particle discrimination accuracy. • The Gaussian Mixture Model-based classifier autonomously configures in engineering applications without human intervention. [ABSTRACT FROM AUTHOR]

Highlights: High porosity and low modulus of the active layer are found to contribute to high sensitivity in a capacitive pressure sensor. Pressure sensor achieves a superhigh sensitivity of 9280 kPa-1 by using polyurethane-ionic liquid foam with a high porosity (95.4%) and a low modulus (3.4 kPa). Flexible pressure sensors with high sensitivity are desired in the fields of electronic skins, human–machine interfaces, and health monitoring. Employing ionic soft materials with microstructured architectures in the functional layer is an effective way that can enhance the amplitude of capacitance signal due to generated electron double layer and thus improve the sensitivity of capacitive-type pressure sensors. However, the requirement of specific apparatus and the complex fabrication process to build such microstructures lead to high cost and low productivity. Here, we report a simple strategy that uses open-cell polyurethane foams with high porosity as a continuous three-dimensional network skeleton to load with ionic liquid in a one-step soak process, serving as the ionic layer in iontronic pressure sensors. The high porosity (95.4%) of PU-IL composite foam shows a pretty low Young's modulus of 3.4 kPa and good compressibility. A superhigh maximum sensitivity of 9,280 kPa−1 in the pressure regime and a high pressure resolution of 0.125% are observed in this foam-based pressure sensor. The device also exhibits remarkable mechanical stability over 5,000 compression-release or bending-release cycles. Such high porosity of composite structure provides a simple, cost-effective and scalable way to fabricate super sensitive pressure sensor, which has prominent capability in applications of water wave detection, underwater vibration sensing, and mechanical fault monitoring. [ABSTRACT FROM AUTHOR]

This paper uses the data envelopment analysis (DEA) approach to solve the issue of allocating fixed costs among a set of decision-making units (DMUs) with two-stage network structure. Fixed cost allocation is a prominent issue that is encountered by organizations, and it is one of the most important applications of DEA. It exists not only in single-stage systems but in two-stage network systems, such as bank systems in real situations, which comprises the deposits process and lending process. However, branch banks often compete with one another out of self-interest. The objective of this paper is to design a fair allocation scheme for two-stage network systems and considering the noncooperative game relationship among DMUs. The idea of satisfaction degree and noncooperative game theory is integrated into the proposed allocation model. In the noncooperative framework, we define a DMU's payoff as the product of two substage satisfaction degree, and every member is noncooperative and selfishly seeks to maximize its own payoff. The allocation plan to DMUs and substages is determined by the final competition payoff. A real case is analyzed to illustrate the applicability of the proposed approaches. [ABSTRACT FROM AUTHOR]

Crack measurement after thermal shock is usually considered as a replacement because real-time observation of thermal shock experiments is difficult to achieve. This paper presents an experimental approach for real-time displaying thermal shock cracking using oxygen-acetylene flame and high-speed imaging of translucent ceramic. We capture the crack propagation process, calculate the crack propagation speed, discuss the effect of sample size and flame heat flux on the crack propagation, and analyze the difference between the crack propagation under cold shock and hot shock. This paper further improves the mechanism of thermal shock damage of ceramic materials. [ABSTRACT FROM AUTHOR]

In this paper, ER50-6 steel was fabricated by wire arc additive manufacturing (WAAM) with an A-W GTAW system. The microstructure, mechanical properties, and corrosion behaviors of ER50-6 steel by WAAM were studied. The results showed that, with the GMAW current increased, from the bottom to the top of the sample, the microstructure was fine ferrite and granular pearlite, ferrite equiaxed grains with fine grains at grain boundaries, and columnar ferrite, respectively. The average hardness in the vertical direction of samples 1# and 2# was 146 and 153 HV, respectively. The hardness of sample 2# increased because of the refinement of grain. The pores in the sample increased as the bypass current increased. The higher bypass current also has a deterioration effect on the corrosion behavior of ER50-6 steel. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to accomplish robust actuator fault isolation and identification for microsatellite attitude control systems (ACSs) subject to a series of space disturbance torques and gyro drifts. Design/methodology/approach: For the satellite attitude dynamics with Lipschitz constraint, a multi-objective nonlinear unknown input observer (NUIO) is explored to accomplish robust actuator fault isolation based on a synthesis of Hinf techniques and regional pole assignment technique. Subsequently, a novel disturbance-decoupling learning observer (D2LO) is proposed to identify the isolated actuator fault accurately. Additionally, the design of the NUIO and the D2LO are reformulated into convex optimization problems involving linear matrix inequalities (LMIs), which can be readily solved using standard LMI tools. Findings: The simulation studies on a microsatellite example are performed to prove the effectiveness and applicability of the proposed robust actuator fault isolation and identification methodologies. Practical implications: This research includes implications for the enhancement of reliability and safety of on-orbit microsatellites. Originality/value: This study proposes novel NUIO-based robust fault isolation and D2LO-based robust fault identification methodologies for spacecraft ACSs subject to a series of space disturbance torques and gyro drifts. [ABSTRACT FROM AUTHOR]

Online task assignment is one of the core research issues of spatio-temporal crowdsourcing technology. The current researches on minimizing travel cost all focus on the scenario of two objectives (task requesters and workers). This paper proposes a two-stage framework (GH) based on Greedy algorithm and Hungarian algorithm for three-objective online task assignment to minimize travel cost. In order to further optimize the efficiency and average travel cost, this paper proposes GH-AT (Adaptive Threshold) algorithm based on GH algorithm, and redesigns the Hungarian algorithm into the sHungarian algorithm. sHungarian algorithm has lower time complexity than Hungarian algorithm. sHungarian algorithm is not only suitable for the problem studied in this paper, but also for all task assignment problems with constraints. Compared with Greedy algorithm, GH-AT algorithm has lower travel cost and higher total utility. In terms of the number of matches, GH-AT is slightly lower than Greedy algorithm. In terms of time cost, GH-AT algorithm is higher than Greedy algorithm, but much lower than GH algorithm. [ABSTRACT FROM AUTHOR]

• There is a phenomenon of secondary opening and closing in the flowering process of a single flower in Magnolia × soulangeana 'Hongyun'. • The synchronism of pollen viability and stigma receptivity suggests that dichogamy might be a morphological concept in 'Hongyun'. • The morphological dichogamy may relate to the breeding system type of 'Hongyun' which is partially self-compatible, outcrossing, and demands pollinators. Magnolia soulangeana 'Hongyun' is an ornamental tree used for landscaping. It has an attractive shape and produces abundant showy flowers. However, the fruit set rate of 'Hongyun' is low under natural pollination condition. In this study, we examined the basic characteristics of its breeding system. The results showed that the flower of 'Hongyun' is hermaphroditic, with both pistil and stamen being fertile. The pollen-ovule ratio (P/O) ranged from 3,205.78 to 6,244.21, and the outcrossing index (OCI) was 4. Comparing with different pollination treatments, we found that there was no fruit set under direct bagging, bagging after emasculation, and no bagging and non-pollination after emasculation. Furthermore, the fruit set rate under the geitonogamy treatment was lower than that under the xenogamy treatment, indicating low self-compatibility. Therefore, when combined with the numerical value of P/O and OCI, we infer that the breeding system of 'Hongyun' is partially self-compatible, outcrossing, and demands pollinators. In particular, 'Hongyun' presents a mass-flowering pattern. Furthermore, there is the phenomenon of secondary opening and closing in the flowering process of a single flower. The stigma receptivity and pollen viability of a flower are the strongest when it is slightly blooming during the first flowering. Strangely, the anther wall dehiscence occurs during the second flowering, which may guarantee that 'Hongyun' maintains a morphological dichogamy status to avoid self-fertilization. Overall, the unique flowering dynamics is closely related to the type of breeding system in 'Hongyun'. Group planting will be the best way to promote better reproductive success of 'Hongyun' under garden planting conditions. [ABSTRACT FROM AUTHOR]

Rotavirus B (RVB) is a causative agent leading to acute viral gastroenteritis diarrhea in both children and young animals, and has been commonly detected in piglets. In order to determine the causative agent of diarrheal outbreak occurring in December 2022 in piglets from a pig herd in Luoyang, Henan province of China, four common viral pathogens causing piglet diarrhea-three coronaviruses and rotavirus A (RVA) were first tested and found negative, therefore metagenomic sequencing was performed to explore other potential pathogens in the diarrheal samples. Unexpectedly, the most abundant viral reads mapped to RVB, and were de novo assembled to complete 11 viral gene segments. Sequence comparisons revealed that 5 gene segments encoding VP1, VP2, VP3, NSP3 and NSP4 of RVB strain designated as HNLY-2022 are most closely related to RVB strains derived from herbivores with low nucleotide similarities of 65.7–75.3%, and the remaining segments were relatively close to porcine RVB strains with the VP4 gene segment showing very low nucleotide identity (65.0%) with reference strains, indicating HNLY-2022 is a new reassortant RVB strain. Based on the previously proposed genotype classification criterion, the genotype constellation of RVB strain HNLY-2022 is G6-P[6]-I4-R6-C6-M6-A7-N5-T7-E5-H4 with more than half of the genotypes (P[6], R6, C6, M6, T7 and E5) newly reported. Therefore, the new reassortant RVB strain is the likely causative agent for the diarrheal outbreak of piglets occurred in China and more epidemiological studies should be conducted to monitor the spread of this newly identified porcine RVB strain. • Outbreak of piglet diarrhea occurred in Henan province of China was associated with a new rotavirus B. • HNLY-2022 is a reassortant RVB strain with the gene segments probably arose from pigs and herbivores. • The genotypes P[6], R6, C6, M6, T7 and E5 of RVB were firstly identified. [ABSTRACT FROM AUTHOR]

Due to the structural complexity and size, many gravity net cage array prototypes are modeled, simulated, and analyzed to select the potential mooring system. However, the complexity of these systems requires a significant amount of time to configure and compute the mooring dynamics in the preliminary design stage. Because the net cage array reaches an equilibrium state in a specific current condition, the cable tension is static and predictable for a given mooring system configuration. Therefore, based on a quasi-static method, load formulas that resolve cable tension are derived to reflect relationships among the cable tension, net cage array size, mooring system configuration, and current conditions. Compared to the tension obtained from numerical simulations, the cable tension predicted by the formulas has a 67% probability of error within ±5%, and a 96% probability of error within ±10%, respectively. Additionally, the formula characteristics also provide valuable information for the mooring system design. The mooring system of a 2 × 4 net cage array is designed according to the derived cable tension formulas. This research provides an efficient and rapid method for preliminary design and sizing components for a mooring system of gravity net cage array. • Gravity net cage arrays in currents are analyzed by using numerical simulations. • Formulas are derived to reflect relationships among cable tension, mooring system configuration and current. • Cable tension in current is predicted accurately and efficiently by using the formulas. • An efficient method is provided for preliminary design a mooring system of gravity net cage array. [ABSTRACT FROM AUTHOR]

This study reports the synthesis and characterization of four europium (III) complexes with different carboxylate ligands, namely 2-pyridine-acrylic acid (H2-PA), 2-pyridine-carboxylic acid (HPic), benzoic acid (HBen), and cinnamic acid (HCin), as well as a binuclear europium-lanthanum complex with HCin as the only ligand. The obtained complexes and the light conversion films prepared from them were extensively characterized by various techniques, including elemental analysis, infrared spectroscopy (IR), X-ray single crystal diffraction, thermogravimetric analysis (TGA), and fluorescence spectroscopy. Efforts were made to systemically investigate the structural, coordination, photophysical, and thermal properties of the luminescent materials, and elucidate the correlations between the ligand triplet energy levels and the luminescent properties of the complexes. The results reveal that the introduction of LaIII cannot only enhance the luminescent intensity of the light conversion agent and corresponding film, but also have obvious effect on enhancing the ultraviolet aging resistance of the light conversion film. Moreover, the proper doping concentration (0.5%) of the EuIII complex La-Eu-Cin in film may better balance the properties and cost. [Display omitted] • Systematical investigation of the effect of the structures of carboxylate ligands on the luminescence properties of the EuIII complexes and the corresponding light conversion films. • Doping lanthanum ion can improve both of luminescence and ultraviolet aging resistance properties of the EuIII complex and light conversion film. • The proper doping concentration (0.5%) of the EuIII complex La-Eu-Cin in the light conversion film may better balance the properties and cost. [ABSTRACT FROM AUTHOR]

This paper addresses the robust attitude synchronization issue in a multi-spacecraft formation system subjected to limited communication, space disturbances, modeling uncertainties, and actuator faults. To accommodate limited inter-spacecraft communication, a dynamic event-triggered mechanism is designed to reduce the communication trigger frequency by dynamically adjusting the trigger threshold. Moreover, an event-based distributed self-learning neural-network control (SLN2C) law is developed to guarantee robust attitude synchronization during multi-spacecraft formation. In the SLN2C scheme, a learning radial basis function neural network (RBFNN) model is proposed to online approximate and compensate for lumped disturbances, in which an iterative learning algorithm with a variable learning intensity is adopted to update the weight matrix of the RBFNN model. Compared with the traditional fixed learning intensity, a variable one can reduce initial oscillation and weaken the saturation response. Numerical simulations and comparisons are performed to illustrate the effectiveness and superiority of the proposed event-based spacecraft attitude synchronization control method. [ABSTRACT FROM AUTHOR]

This paper addresses the robust attitude synchronization issue in a multi-spacecraft formation system subjected to limited communication, space disturbances, modeling uncertainties, and actuator faults. To accommodate limited inter-spacecraft communication, a dynamic event-triggered mechanism is designed to reduce the communication trigger frequency by dynamically adjusting the trigger threshold. Moreover, an event-based distributed self-learning neural-network control (SLN2C) law is developed to guarantee robust attitude synchronization during multi-spacecraft formation. In the SLN2C scheme, a learning radial basis function neural network (RBFNN) model is proposed to online approximate and compensate for lumped disturbances, in which an iterative learning algorithm with a variable learning intensity is adopted to update the weight matrix of the RBFNN model. Compared with the traditional fixed learning intensity, a variable one can reduce initial oscillation and weaken the saturation response. Numerical simulations and comparisons are performed to illustrate the effectiveness and superiority of the proposed event-based spacecraft attitude synchronization control method. [ABSTRACT FROM AUTHOR]

• To manage contingent liabilities, government sets a charging mechanism of guarantee. • Optimal BOT contract is investigated under a paid MTG program. • A paid MTG program is at the expense of the social welfare. • The impact of guarantee program on welfare loss is amplified by marginal social cost. • The risk averse attitude would lower service quality and decrease social welfare. Government sectors often provide guarantees in build-operate-transfer (BOT) roads to attract private investments. Since a fiscal burden would be incurred from the contingent liability of issuing a guarantee, charging a fee for the guarantee is considered an effective remedy for management of contingent liabilities in practice. This study incorporates the charge mechanism for minimum traffic guarantee (MTG) into consideration, and proposes a method to choose the optimal concession contract variables with a paid MTG. We find that the government sector will specify a lower toll and a higher capacity for a BOT road with a paid MTG. As a result, the society suffers a social welfare loss when providing a paid MTG. Meanwhile, both the charging fee of an MTG and the guaranteed traffic volume would increase the loss of social welfare, which means the incentive mechanism of private participation and the management of contingent liabilities (charging fee for MTG) are all at the expense of social welfare. Moreover, since the welfare loss is magnified under a high marginal social cost condition, the government should set the charging fee and guaranteed traffic volume according to the marginal social cost level. In addition, to obtain more insights, this paper has made two extensions to further investigate the effects of a paid MTG (1) when contracting with a risk averse private investor; (2) when the concession period is an endogenous variable. Based on our model results, this paper derives several policy implications regarding BOT contract design when a paid MTG is provided. [ABSTRACT FROM AUTHOR]

Recent data on the coronavirus disease 2019 (COVID-19) outbreak caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has begun to shine light on the impact of the disease on the liver. But no studies to date have systematically described liver test abnormalities in patients with COVID-19. We evaluated the clinical characteristics of COVID-19 in patients with abnormal liver test results. Clinical records and laboratory results were obtained from 417 patients with laboratory-confirmed COVID-19 who were admitted to the only referral hospital in Shenzhen, China from January 11 to February 21, 2020 and followed up to March 7, 2020. Information on clinical features of patients with abnormal liver tests were collected for analysis. Of 417 patients with COVID-19, 318 (76.3%) had abnormal liver test results and 90 (21.5%) had liver injury during hospitalization. The presence of abnormal liver tests became more pronounced during hospitalization within 2 weeks, with 49 (23.4%), 31 (14.8%), 24 (11.5%) and 51 (24.4%) patients having alanine aminotransferase, aspartate aminotransferase, total bilirubin and gamma-glutamyl transferase levels elevated to more than 3× the upper limit of normal, respectively. Patients with abnormal liver tests of hepatocellular type or mixed type at admission had higher odds of progressing to severe disease (odds ratios [ORs] 2.73; 95% CI 1.19–6.3, and 4.44, 95% CI 1.93–10.23, respectively). The use of lopinavir/ritonavir was also found to lead to increased odds of liver injury (OR from 4.44 to 5.03, both p <0.01). Patients with abnormal liver tests were at higher risk of progressing to severe disease. The detrimental effects on liver injury mainly related to certain medications used during hospitalization, which should be monitored and evaluated frequently. Data on liver tests in patients with COVID-19 are scarce. We observed a high prevalence of liver test abnormalities and liver injury in 417 patients with COVID-19 admitted to our referral center, and the prevalence increased substantially during hospitalization. The presence of abnormal liver tests and liver injury were associated with the progression to severe pneumonia. The detrimental effects on liver injury were related to certain medications used during hospitalization, which warrants frequent monitoring and evaluation for these patients. • Of 417 patients with COVID-19, 76.3% had abnormal liver tests and 21.5% had liver injury during hospitalization. • Patients with abnormal liver tests had significantly higher odds of developing severe pneumonia. • The use of lopinavir/ritonavir increased the odds of liver injury by 4-fold. [ABSTRACT FROM AUTHOR]

Background: Through the comparison of three-dimensional CT reconstruction between the supine position and the prone position, the relative position of thoracolumbar great vessels and vertebral body was studied, and the shortest safe distance between them was measured to improve the safety of bicortical pedicle screw insertion and reduce the risk of vascular injury.Methods: Forty adults were selected to participate the research. Three-dimensional reconstruction of thoracolumbar (T9-L3) CT was performed in the prone position and the supine position. The relative distance between the Aorta/Inferior Vena Cava (IVC) and vertebral body was obtained as AVD/VVD respectively. The relative angle of the Aorta/ IVC and the vertebral body was calculated as ∠AOY/∠VOY. Self-controlled experiments were carried out in the prone and the supine positions, and the data obtained were analyzed using SPSS 22.0 statistical software.Results: The AVD of the prone position and the supine position was the shortest at T12 (3.18 ± 0.68 mm), but the difference was not statistically significant. The aorta of the T9-L3 segment was shifted from the anterolateral to the anteromedial. The ∠AOY of the other groups differed significantly between the prone and supine positions in all vertebrae except T12 and L1 (P < 0.05), and the aorta in the prone position was more anteromedial than that of supine position. With regard to VVD/∠VOY, there was no significant difference between the prone and supine positions (P ≥ 0.05), and the minimum VVD of L3 segment is greater than 5.4 mm. The IVC has no obvious mobility and is fixed in the range of 20 ° ~ 30 ° near the midline.Conclusion: When using bicortical anchoring of pedicle screws, it is safe to ensure that the protruding tips of the screw is less than 3 mm. Due to the mobility of the aorta in different postures and individual differences in anatomy, the prone position CT can help doctors to make better preoperative plans and decisions. [ABSTRACT FROM AUTHOR]

The high-tech industry in China has largely developed in recent decades. To provide a basis for the sustainable development of high-tech industry, the government should evaluate its performance to find out its strengths and weaknesses that are critical for the future improvement of business operations. Dynamic network data envelopment analysis has received considerable attention from researchers evaluating the performance of a system during long-term production. However, studies on the issue of shared outputs caused by the lagged production effect of inputs are rare. In a real high-tech industry, the outputs during a production period are derived from the inputs in that production period and also from the inputs in the previous period. These intertemporal shared outputs in a system cannot be easily divided into different periods. Thus, a new dynamic two-stage data envelopment analysis approach is proposed to measure the efficiency of such system with a two-stage structure and shared outputs. We divide a high-tech activity system into two stages: technology research and development stage and technology digestion and absorption stage, where intertemporal shared outputs occur. Empirical results from our approach indicate that Chinese high-tech industries are weak in the technology digestion and absorption stage. Finally, suggestions are provided to improve the overall efficiency of Chinese high-tech industries. [ABSTRACT FROM AUTHOR]

Objective: Patients with obesity are at increased risk of exacerbations from viral respiratory infections. However, the association of obesity with the severity of coronavirus disease 2019 (COVID-19) is unclear. We examined this association using data from the only referral hospital in Shenzhen, China.Research Design and Methods: A total of 383 consecutively hospitalized patients with COVID-19 admitted from 11 January 2020 to 16 February 2020 and followed until 26 March 2020 at the Third People's Hospital of Shenzhen were included. Underweight was defined as a BMI <18.5 kg/m2, normal weight as 18.5-23.9 kg/m2, overweight as 24.0-27.9 kg/m2, and obesity as ≥28 kg/m2.Results: Of the 383 patients, 53.1% were normal weight, 4.2% were underweight, 32.0% were overweight, and 10.7% were obese at admission. Obese patients tended to have symptoms of cough (P = 0.03) and fever (P = 0.06) compared with patients who were not obese. Compared with normal weight patients, those who were overweight had 1.84-fold odds of developing severe COVID-19 (odds ratio [OR] 1.84, 95% CI 0.99-3.43, P = 0.05), while those who were obese were at 3.40-fold odds of developing severe disease (OR 3.40, 95% CI 1.40-2.86, P = 0.007), after adjusting for age, sex, epidemiological characteristics, days from disease onset to hospitalization, presence of hypertension, diabetes, cardiovascular disease, chronic obstructive pulmonary disease, liver disease, and cancer, and drug used for treatment. Additionally, after similar adjustment, men who were obese versus those who were normal weight were at increased odds of developing severe COVID-19 (OR 5.66, 95% CI 1.80-17.75, P = 0.003).Conclusions: In this study, obese patients had increased odds of progressing to severe COVID-19. As the severe acute respiratory syndrome coronavirus 2 may continue to spread worldwide, clinicians should pay close attention to obese patients, who should be carefully managed with prompt and aggressive treatment. [ABSTRACT FROM AUTHOR]

Background: The clinical characteristics of novel coronavirus disease (COVID‐2019) patients outside the epicenter of Hubei Province are less understood. Methods: We analyzed the epidemiological and clinical features of all COVID‐2019 cases in the only referral hospital in Shenzhen City, China, from January 11, 2020, to February 6, 2020, and followed until March 6, 2020. Results: Among the 298 confirmed cases, 233 (81.5%) had been to Hubei, while 42 (14%) did not have a clear travel history. Only 218 (73.15%) cases had a fever as the initial symptom. Compared with the nonsevere cases, severe cases were associated with older age, those with underlying diseases, and higher levels of C‐reactive protein, interleukin‐6, and erythrocyte sedimentation rate. Slower clearance of the virus was associated with a higher risk of progression to critical condition. As of March 6, 2020, 268 (89.9%) patients were discharged and the overall case fatality ratio was 1.0%. Conclusions: In a designated hospital outside Hubei Province, COVID‐2019 patients could be effectively managed by properly using the existing hospital system. Mortality may be lowered when cases are relatively mild, and there are sufficient medical resources to care and treat the disease. [ABSTRACT FROM AUTHOR]

Chaos optimization algorithm (COA) usually utilizes chaotic maps to generate the pseudorandom numbers mapped as the decision variables for global optimization problems. Recently, COA has been applied to many single objective optimization problems and simulations results have demonstrated its effectiveness. In this paper, a novel parallel chaos optimization algorithm (PCOA) will be proposed for multiobjective optimization problems (MOOPs). As an improvement to COA, the PCOA is a kind of population-based optimization algorithm which not only detracts the sensitivity of initial values but also adjusts itself suitable for MOOPs. In the proposed PCOA, crossover and merging operation will be applied to exchange information between parallel solutions and produce new potential solutions, which can enhance the global and fast search ability of the proposed algorithm. To test the performance of the PCOA, it is simulated with several benchmark functions for MOOPs and mixed H 2 / H ∞ controller design. The simulation results show that PCOA is an alternative approach for MOOPs. [ABSTRACT FROM AUTHOR]

Human–computer interfaces, smart glasses, touch screens, and some electronic skins require highly transparent and flexible pressure‐sensing elements. Flexible pressure sensors often apply a microstructured or porous active material to improve their sensitivity and response speed. However, the microstructures or small pores will result in high haze and low transparency of the device, and thus it is challenging to balance the sensitivity and transparency simultaneously in flexible pressure sensors or electronic skins. Here, for a capacitive‐type sensor that consists of a porous polyvinylidene fluoride (PVDF) film sandwiched between two transparent electrodes, the challenge is addressed by filling the pores with ionic liquid that has the same refractive index with PVDF, and the transmittance of the film dramatically boosts from 0 to 94.8% in the visible range. Apart from optical matching, the ionic liquid also significantly improves the signal intensity as well as the sensitivity due to the formation of an electric double layer at the dielectric‐electrode interfaces, and improves the toughness and stretchability of the active material benefiting from a plasticization effect. Such transparent and flexible sensors will be useful in smart windows, invisible bands, and so forth. [ABSTRACT FROM AUTHOR]