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Abstract Objective To investigate the association between syndesmophytes and facet joint (FJ) lesions in patients with ankylosing spondylitis (AS), and to identify clinical factors associated with FJ ankylosis (FJA) in thoracic segment. Methods Ninety-seven patients with AS who underwent thoracic spine computed tomography (CT) or chest CT and without completely thoracic spine fusion were included. FJ lesions were analyzed for the numbers and distribution of normal, ankylosis, erosions, joint-space narrowing, osteophytes, and subchondral sclerosis. The volume of vertebral syndesmophtes unit (VSU) and total thoracic syndesmophtes volume were separately calculated by Mimics software. Clinical factors associated with FJA were investigated using generalized estimation equation (GEE). The association between syndesmophtes volume and numbers of FJ structural lesions was analyzed using generalized additive mixed model (GAMM). Results 2328 FJ and 1164 VSUs in thoracic spine were assessed. The majority FJ structural lesions were ankylosis (32.39%). FJA was more frequently seen in vertebrae with syndesmophytes formation (p 24.9 kg/m2) were more likely to have FJA in thoracic spine (odds rations [95% confidence interval]: 0.27(0.12–0.59), 1.45(1.03–8.57), respectively). GAMM showed that syndesmophytes volume increase the numbers of FJA (standard β = 0.009, p 24.9 kg/m2) and increased syndesmophytes volume are associated with FJA in thoracic spine.

Abstract This research addresses the challenge faced by most existing prediction methods in handling nonlinear data of cables. Furthermore, it proposes a novel power cable monitoring method utilizing UHF‐RFID and deep learning within an edge computing environment, specifically targeting the currently suboptimal wireless monitoring of cables. First, based on edge computing, a power cable monitoring system is designed to migrate the analysis of massive data to the edge of the network to improve the monitoring efficiency. Then, the temperature sensing chip and RFID chip were integrated to design a UHF‐RFID temperature tag, which was fixed at the cable temperature measurement point to achieve passive wireless monitoring of the cable. Finally, the parameters of the GRNN model are optimized using the beetle antennae search algorithm, and the EEMD decomposed data is input into the BAS‐GRNN model for learning to output temperature prediction results. Based on the establishment of an experimental platform, the method was demonstrated, and results showed that the maximum error between the UHF‐RFID temperature tag temperature measurement results and the thermocouple was within 0.3°C, and the average relative error of the proposed method was only 0.01, which can meet the accuracy requirements of actual monitoring of power cables.

Abstract Glutamate dehydrogenase 1 (GLUD1) is an important enzyme in glutamine metabolism. Previously, we found GLUD1 was down-regulated in tumor tissues of hepatocellular carcinoma (HCC) patients by proteomics study. To explore its role in the progression of HCC, the expressional level of GLUD1 was firstly examined and presented as that both the protein and mRNA levels were down-regulated in tumor tissues compared to the normal liver tissues. GLUD1 overexpression significantly inhibited HCC cells proliferation, migration, invasion and tumor growth both in vitro and in vivo, while GLUD1 knocking-down promoted HCC progression. Metabolomics study of GLUD1 overexpressing and control HCC cells showed that 129 differentially expressed metabolites were identified, which mainly included amino acids, bases, and phospholipids. Moreover, metabolites in mitochondrial oxidative phosphorylation system (OXPHOS) were differentially expressed in GLUD1 overexpressing cells. Mechanistic studies showed that GLUD1 overexpression enhanced mitochondrial respiration activity and reactive oxygen species (ROS) production. Excessive ROS lead to mitochondrial apoptosis that was characterized by increased expression levels of p53, Cytochrome C, Bax, Caspase 3 and decreased expression level of Bcl-2. Furthermore, we found that the p38/JNK MAPK pathway was activated in GLUD1 overexpressing cells. N-acetylcysteine (NAC) treatment eliminated cellular ROS and blocked p38/JNK MAPK pathway activation, as well as cell apoptosis induced by GLUD1 overexpression. Taken together, our findings suggest that GLUD1 inhibits HCC progression through regulating cellular metabolism and oxidative stress state, and provide that ROS generation and p38/JNK MAPK pathway activation as promising methods for HCC treatment.

The Microwave Radiation Imager (MWRI) onboard the FengYun satellite plays a crucial role in global change monitoring and numerical weather prediction. Estimating and correcting geolocation errors are important to retrieving accurate geophysical variables. However, the instantaneous field of view (IFOV) inter-channel deviation, which is mainly caused by the structure mounting error and measurement error of feedhorns, is less studied. In this present study, we constructed a general theoretical model to automatically estimate the IFOV inter-channel deviations suitable for conical-scanning instruments. The model can automatically detect the along-track and across-track vectors that pass through the land–sea boundary points and are perpendicular to the actual coastlines. Regarding the midpoints of the vectors as the brightness temperature (Tb) inflection points, the IFOV inter-channel deviation is the pixel offset or distance of the maximum gradients of the Tb near the inflection points for each channel relative to the 89-GHz V-pol channel. We tested the model’s operational performance using the FY-3G/MWRI-Rainfall Mission (MWRI-RM) observations. Considering that parameter uploading adjusted the IFOV inter-channel deviations, the model’s validity was verified by comparing the adjustments calculated by the model with the theoretical changes caused by parameter uploading. The result shows that the differences between them for all window channels are less than 100 m, indicating the model’s effectiveness in evaluating the IFOV inter-channel deviation for the MWRI-RM. Furthermore, the estimated on-orbit IFOV inter-channel deviations for the MWRI-RM show that all channel deviations are less than 1 km, meeting the instrument’s design requirement of 2 km. We believe this study will provide a foundation for IFOV inter-channel registration of passive microwave payloads and spatial matching of multiple payloads.

Based on introducing the technical characteristics of FY-3G, which is China's first precipitation measurement satellite and successfully launched at 09∶36 BT on April 16 in 2023, this paper focuses on the precipitation detection capabilities and application prospect in rainstorm monitoring of FY-3G. The results show that, with an orbit at 407 km and an inclination angle of 50°, and equipped with a dual-frequency Ka/Ku band precipitation measurement radar, microwave, and optical imaging instruments, the FY-3G satellite can detect the three-dimensional structure of disastrous weather systems such as typhoon, heavy rainfall, and other strong convection events in most of China. At the design level, FY-3G has precipitation detection capabilities comparable to the current US Second Generation Global Precipitation Measurement Program (GPM) Core Satellite (GPMCO), but better payload types, quantities, and channel settings compared with the GPMCO satellite. After the service operation, the FY-3G satellite, together with other polar-orbiting meteorological satellites such as FY-3 AM, PM, and EM, as well as high-orbit geostationary satellites, will form the Fengyun precipitation detection constellation system, which will improve the overall precipitation detection capability of the Fengyun Satellite constellation and provide stronger basic support for meteorological disaster prevention and mitigation.

Background and Purpose: Emerging researches have regarded serum chloride as a capable predictor of mortality in liver cirrhosis. We aim to investigate the clinical role of admission chloride in cirrhotic patients with esophagogastric varices receiving transjugular intrahepatic portosystemic shunt (TIPS), which is unclear. Methods: We retrospectively analyzed data of cirrhotic patients with esophagogastric varices undergoing TIPS in Zhongnan Hospital of Wuhan University. Mortality outcome was obtained by following up for 1-year after TIPS. Univariate and multivariate Cox regression were used to identify independent predictors of 1-year mortality post-TIPS. The receiver operating characteristic (ROC) curves were adopted to assess the predictive ability of the predictors. In addition, log-rank test and Kaplan–Meier (KM) analyses were employed to evaluate the prognostic value of predictors in the survival probability. Results: A total of 182 patients were included ultimately. Age, fever symptom, platelet-to lymphocyte-ratio (PLR), lymphocyte-to-monocyte ratio (LMR), total bilirubin, serum sodium, chloride, and Child-Pugh score were related to 1-year follow-up mortality. In multivariate Cox regression analysis, serum chloride (HR = 0.823, 95%CI = 0.757–0.894, p

The Airborne Terahertz Ice Cloud Imager (ATICI) is an airborne demonstration prototype of an ice cloud imager (ICI), which will be launched on the next generation of Fengyun satellites and plays an important role in heavy precipitation detection, typhoon, and medium-to-short-term meteorological/ocean forecasting. At present, it has 13 frequency channels covering 183–664 GHz, which are sensitive to scattering by cloud ice. This paper provides an overview of ATICI and proposes a receiving front-end design scheme using a planar mirror and a quasi-optical feed network which improves the main beam efficiency of each frequency band, with measured values better than 95.5%. It can detect factors such as ice particle size, ice water path, and ice water content in clouds by rotating the circular scanning of the antenna feed system. A high-sensitivity receiver system has been developed and tested for verification. The flight verification results show that the quasi-optical feed network subsystem works well and performs stably under vibration and temperature changes. The system sensitivity is better than 1.5 K, and the domestically produced high-frequency receiver has stable performance, which can meet the conditions of satellite applications. The ATICI performs well and meets expectations, verifying the feasibility of the Fengyun-5 ICI payload.

The surface of AISI 52100 steel was pre-treated by laser remelting with different powers, and the vanadizing layer were prepared on remelted steel by pack cementation. The microstructure and properties of vanadizing layer were investigated by XRD, microhardness tester, metallographic microscope, scanning electron microscope, energy dispersive spectrometer, friction and wear tester. The critical load Lc was determined by observing the micro-scratch morphology of scratches through micro-scratch experiments, and its wear performance was studied. The results show that the hardness of remelting zone increase with the increase of laser power. When the laser power is 500 W, the microhardness is 424.6 HV0.2. The vanadizing layer formed on the remelting surfaces is uniform and dense. The layers are mainly composed of VCx phase and α-Fe/α′-Fe phase, the VC phase has the preferred orientation of (200) and (111) planes. There is a good metallurgical bonding between the vanadizing layer and the steel， and the thickness is 2.7 μm–12.15 μm, the microhardness is 2050.7 HV0.2–2350.9 HV0.2. When the laser remelting power is 300 W, the vanadizing layer is better in thickness, microhardness and average friction coefficient, the bonding force Lc between the vanadizing layer and the substrate is about 41.59 N, and the main failure mode is the spalling of the vanadizing layer. It can be concluded that laser remelting pre-treatment can greatly improve the hardness and wear resistance.

In satellite health management, anomalies are mostly resolved after an event and are rarely predicted in advance. Thus, trend prediction is critical for avoiding satellite faults, which may affect the accuracy and quality of satellite data and even greatly impact safety. However, it is difficult to predict satellite operation using a simple model because satellite systems are complex and telemetry data are copious, coupled, and intermittent. Therefore, this study proposes a model that combines an attention mechanism and bidirectional long short-term memory (attention-BiLSTM) with telemetry correlation to predict satellite behaviour. First, a high-dimensional K-nearest neighbour mutual information method is used to select the related telemetry variables from multiple variables of satellite telemetry data. Next, we propose a new BiLSTM model with an attention mechanism for telemetry prediction. The dataset used in this study was generated and transmitted from the FY3E meteorological satellite power system. The proposed method was compared with other methods using the same dataset used in the experiment to verify its superiority. The results confirmed that the proposed method outperformed the other methods owing to its prediction precision and superior accuracy, indicating its potential for application in intelligent satellite health management systems.

The design of spinel-oxide-based catalysts with high activity and long-term durability for oxygen evolution reaction (OER) confronts grand challenges that may be well tackled by maneuvering the electronic structure of surface catalytic sites within spinel oxides. Herein, we harness a double exchange interaction (DEI) triggered by the synergistic effects of Schottky junction and oxygen vacancies (VO) to generate high proportions of octahedrally coordinated Ni3+ and Co2+ (highly active sites) in the edge-sharing [NixCo1−XO6] octahedra. Specifically, Schottky junction is formed between metallic Cu nanowires and semiconducting NiCo2O4 via a core-shell structure, and abundant VO sites are created in NiCo2O4 via H2 thermal treatment. As expected, the Cu@VO-NiCo2O4 electrocatalyst allows a significantly boosted OER performance, with a low overpotential of 214 mV at 10 mA cm-2 and a small Tafel slope of 64.9 mV dec-1, which outperforms the state-of-the-art RuO2 catalyst and most of reported Ni-Co based OER catalysts. Our work provides some inspirations for designing high-performance spinel-oxide-based electrocatalysts towards OER via DEI engineering.

SARS-CoV-2 spike protein plays a key role in mediating viral entry and inducing host immune responses. It can adopt either an open or closed conformation based on the position of its receptor-binding domain (RBD). It is yet unclear what causes these conformational changes or how they influence the spike’s functions. Here, we show that Lys417 in the RBD plays dual roles in the spike’s structure: it stabilizes the closed conformation of the trimeric spike by mediating inter-spike–subunit interactions; it also directly interacts with ACE2 receptor. Hence, a K417V mutation has opposing effects on the spike’s function: it opens up the spike for better ACE2 binding while weakening the RBD’s direct binding to ACE2. The net outcomes of this mutation are to allow the spike to bind ACE2 with higher probability and mediate viral entry more efficiently, but become more exposed to neutralizing antibodies. Given that residue 417 has been a viral mutational hotspot, SARS-CoV-2 may have been evolving to strike a balance between infection potency and immune evasion, contributing to its pandemic spread.

Abstract Introduction Previous articles reported on the tip–apex distance, lag screw placement, fracture pattern, reduction quality, osteoporosis and other factors associated with second surgery. The current study focused on investigating the association of the matching degree between proximal femoral intramedullary nail and femoral medullary cavity on reoperation rate. Patients and methods A retrospective cohort study was conducted. It included patients with intertrochanteric fracture who were treated with proximal femoral anti-rotatory intramedullary nail (PFNA) between January 2016 and April 2021. The gap between the intramedullary nail and the femoral medullary cavity was equal to the difference in diameter between the two. According to the gap size, all patients were divided into three groups, as follows: high-matching group: gap ≤ 2 mm; middle-matching group: 2

In this paper, the tribological behavior of Cu-SiO2 composite against 1045 steel was studied. Based on the characterization of worn surface, worn subsurface and wear debris in morphology and composition, the friction layer effects on the tribological behavior of coupled materials and the wear mechanism were discussed. Abrasive wear and adhesive wear are the dominant mechanisms at the 0.56 m/s–1.12 m/s condition. Delamination wear and oxidation wear are the dominant wear mechanisms at the 1.68 m/s–2.24 m/s condition. Plastic and thermal deformation cause the evolution in morphology and structure of the tribolayer of Cu-SiO2. There is a certain correlation between the friction coefficient and the variation in friction temperature during sliding wear of Cu-SiO2 and 1045 steels. The addition of SiO2 induces the accumulation of frictional heat at the friction interface, which leads to an increase in the average temperature of the contact surface and transfer.

The dry sliding behavior of columnar Cu with vertical orientation (VO) and horizontal orientation (HO) coupling with 1045 steel was studied. The results show that when the sliding distance is 672 m, the friction coefficient of HO Cu is 0.21 lower than that of VO Cu, and the wear rate is reduced by 0.63·10 ^−6 g·N ^−1 m ^−1 ; when the sliding distance is 1344 m, the friction coefficient of HO Cu is 0.10 lower than that of VO Cu, and the wear rate is reduced by 0.31·10 ^−6 g·N ^−1 m ^−1 . The Fe _3 O _4 oxide was detected on the wear surface of HO Cu by Raman spectroscopy. And it plays a greater role in lubrication and protection of friction layer. On the worn surface of VO Cu, there is obvious softening caused by thermal activation or composition mixing. This softening will lead to a significant decrease in the strength of the friction layer, and the friction coefficient and wear loss increase negatively.

The in situ Ti _43 Zr _27 Mo _5 Cu _10 Be _15 amorphous composites were investigated for their corrosion properties in solutions of NaCl, HCl, H _2 SO _4 and NaOH. Electrochemical testing, SEM, EDS and XPS analyses revealed that pitting in NaCl and HCl solutions caused local surfaces damage. Amorphous matrix corrodes slightly in H _2 SO _4 solution. Uniform corrosion occurred in NaOH solution without passive film formed, leading to the worst corrosion resistance. The optimal corrosion performances for NaCl and HCl solution are achieved at 0.5 mol l ^−1 and 0.75 mol l ^−1 separately which is related to the shortage of oxygen content in the solutions. While, the best corrosion performances for H _2 SO _4 and NaOH solution are at 0.25 mol l ^−1 . Moreover, the research on the effect of temperature was conducted in 3.5 wt% NaCl solution, it was found that Ti _43 Zr _27 Mo _5 Cu _10 Be _15 amorphous composites exhibited good corrosion resistance at 298 K, while the E _corr declined with increasing solution temperature.

In this paper, H13 steel was pre-carburized. Then niobizing and vanadizing layers were prepared by pack cementation method. The high temperature friction and wear properties and hot melt loss properties of different layers and substrates were studied by microhardness tester, metallographic microscope, scanning electron microscope, energy dispersive spectrometer, high temperature friction and wear tester, optical profilometer and Raman spectrometer. The results show that the thickness of the vanadizing layer is 12.7 μ m, and the microhardness of the niobizing layer and the vanadizing layer is close, which is about 5 times that of the matrix. The lowest wear rate at 500 °C of the vanadizing layer is 1.03 , which is about 1/6 of the matrix. The vanadizing layer and niobiumizing layer can effectively reduce the friction coefficient, greatly improve the surface hardness and wear resistance of H13 steel, and prolong its service life. The comprehensive performance of vanadizing layer is the best. The vanadizing and niobiumizing treatment can significantly improve hot melt loss resistance of H13 steel and it can be used to prolong the serving life of hot die casting mold for Al.

Precipitation is one of the most important parameters in Earth system but is hard to measure. China began to develop satellites dedicated to precipitation measurements in the second generation of the FengYun polar-orbiting meteorological satellite program (FY-3). The first of total 2 rainfall missions scheduled, FY-3G, was successfully launched on 16 April 2023 and became the world’s third satellite to measure precipitation with space-borne radar after the tropical rainfall measuring mission in 1997 and global precipitation measurement core observatory in 2014. In this manuscript, we illustrate the platform of FY-3G and instruments mounted in great detail, with additional information about ground segments, designed sensor-based products, and retrieval of geophysical parameters. During the 4 months after launch, the specifications of the platform and instruments are under inspection as calibration and validation are carefully conducted. The first images captured by FY-3G are encouraging, and initial results show a strong capability for providing insights into all kinds of precipitation phenomena. The important work of data processing, such as data assimilation, data fusion between space-based and ground-based radar, and that between polar and geostationary satellites, as well as future applications in weather modification, has been prepared in advance. As a pioneer of China’s rainfall missions, FY-3G greatly improves our ability to provide global precipitation measurements, understand Earth’s water and energy cycle, and forecast extreme events for the benefit of society.

Aiming at the problems of high delay and vulnerable to network attack in the traditional microgrid centralized architecture, a collaborative microgrid security defense method in the edge-computing environment is proposed. First, we build the edge-computing framework for microgrid, deploy the edge-computing server near the equipment terminal to improve the data processing efficiency, and deploy the blockchain in the edge server to ensure the reliability of the system. Then, the fully homomorphic encryption algorithm is used to design the smart contract, and the secure sharing of information is ensured through identity authentication, data encryption call, and so on. Finally, the credibility model is integrated into the election algorithm and is used to build a trusted edge cooperation mechanism to further improve the ability of the system to defend against network attacks. Based on the microgrid model, the experimental demonstration of the proposed method is carried out. The results show that when subjected to a network attack, the current fluctuation range is small and the defense success rate exceeds 95%, which is better than other methods and can better meet the requirements of practical application.

Toll-like receptors (TLRs) are essential for the protection of the host from pathogen infections by initiating the integration of contextual cues to regulate inflammation and immunity. However, without tightly controlled immune responses, the host will be subjected to detrimental outcomes. Therefore, it is important to balance the positive and negative regulations of TLRs to eliminate pathogen infection, yet avert harmful immunological consequences. This study revealed a distinct mechanism underlying the regulation of the TLR network. The expression of sex-determining region Y-box 4 (Sox4) is induced by virus infection in viral infected patients and cultured cells, which subsequently represses the TLR signaling network to facilitate viral replication at multiple levels by a distinct mechanism. Briefly, Sox4 inhibits the production of myeloid differentiation primary response gene 88 (MyD88) and most of the TLRs by binding to their promoters to attenuate gene transcription. In addition, Sox4 blocks the activities of the TLR/MyD88/IRAK4/TAK1 and TLR/TRIF/TRAF3/TBK1 pathways by repressing their key components. Moreover, Sox4 represses the activation of the nuclear factor kappa-B (NF-κB) through interacting with IKKα/α, and attenuates NF-kB and IFN regulatory factors 3/7 (IRF3/7) abundances by promoting protein degradation. All these contributed to the down-regulation of interferons (IFNs) and IFN-stimulated gene (ISG) expression, leading to facilitate the viral replications. Therefore, we reveal a distinct mechanism by which viral pathogens evade host innate immunity and discover a key regulator in host defense.

BackgroundThe COVID-19 pandemic has disrupted the diagnosis, treatment, and care for tuberculosis (TB). Delays in seeking TB care may result in increased community transmission and unfavorable treatment outcomes. We sought to understand the influence of the COVID-19 pandemic on the proportion of patients with TB who delayed seeking the diagnosis and care for TB and explore the reasons for their postponement.MethodsWe surveyed a representative sample of outpatients treated for pulmonary TB from June to November 2020 using an anonymous standardized questionnaire. Multivariable logistic regression was used to calculate adjusted odds ratios (aOR) and 95% confidence intervals (CIs) of factors associated with the postponement of TB care. We used routinely collected surveillance data to assess trends of TB reports before and after the emergence of COVID-19 (2017–2019 vs. 2020–2022) in Tianjin, China.ResultsAmong 358 participants who were diagnosed with pulmonary TB during the COVID-19 response, 61 (17%) postponed seeking TB diagnosis due to COVID-19, with 39 (64%) citing fear as the primary reason. Female sex (aOR:2.0; 95% CI: 1.1–3.7), previous antituberculosis treatment (aOR:3.2; 95%CI: 1.4–7.6), and TB diagnosis during the first-level response (aOR = 3.2, 1.7–6.2) were associated with the postponement. Among all 518 participants receiving antituberculosis treatment, 57 (11%) had postponed their regular healthcare visits due to COVID-19, 175 (34%) received no treatment supervision, and 32 (6%) experienced treatment interruption. Compared to 2017–2019, reported pulmonary TB declined by 36.8% during the first-level response to COVID-19, 23.5% during the second-level response, 14% during the third-level response in 2020, and 4.3% in 2021.ConclusionThe COVID-19 response reduced the number of people who sought and received diagnosis, treatment, and care for TB in Tianjin, China. Integrative programs to ensure access and continuity of TB services should be considered and dual testing for SARS-CoV-2 and M. tuberculosis may facilitate finding cases.

Osteoarthritis (OA) is characterized by the degeneration of articular cartilage. Decreased autophagy is tightly associated with chondrocyte death, which contributes to the progression of OA. Thus, pharmacological activation of autophagy may be a promising therapeutic approach for OA. Here, we discovered that clioquinol, an antibiotic, significantly induces autophagy in OA chondrocytes from human tissue and rabbit model. Meanwhile, clioquinol can also augment the expression of extracellular matrix (ECM) components and suppress inflammatory mediators to improve OA microenvironment. Intra-articular injection of clioquinol can greatly prevent or slow down the development of this disease in a trauma-induced rabbit model of osteoarthritis. Such protective effect induced by clioquinol was at least in part explained by decreasing chondrocyte apoptosis and increasing autophagy. This study reveals the therapeutic potential of clioquinol in OA treatment.

FY-3E WindRAD (Fengyun-3E Wind Radar) is a dual-frequency rotating fan-beam scatterometer. Its data characteristics, NOC (NWP Ocean Calibration), and wind retrieval performance are investigated in this paper. The diversity of the radar view geometry varies across the swaths, with maximum diversity in the sweet swaths and limited diversity in the outer and nadir swaths. When NOC backscatter calibration coefficients are computed as a function of incidence angle only (NOCint), a smooth correction is found. However, when relative antenna azimuth angle is included (NOCant), it appears that the corrections as a function of relative azimuth angle vary harmonically and substantially for a specific incidence angle. NOCant corrections yield a better fit of the measurements to the GMF (Geophysical Model Function). Hence, NOCant is applied for the analysis of wind retrieval from the Ku-band and C-band. An extra engineering correction of 0.15 dB and 0.20 dB is applied on Ku-band and C-band backscatter values, respectively, to reduce the wind speed bias without increasing the standard deviation. Overall, NOCant is the best option for both channels. In addition, the instrument backscatter data stability over time is good, and the retrieved winds can fulfill operational requirements.

Navigation of images from lightning mapping instruments in geostationary orbits is very important for data applications. However, few scientific peer-reviewed papers have been reported, except a few works in the prelaunch tests. On December 11, 2016, China launched the three-axis stabilized geostationary meteorological satellite Fengyun-4A (FY-4A), which carries a lightning mapping imager (LMI) onboard. LMI is now providing lightning observations above the equator at 104.7˚E and covers a large portion of the eastern Asian continent. In this article, a new method has been set up to perform the image navigation for FY-4A/LMI. First, landmarks were used to calculate thermal deformation parameters and edge-binding technique was proposed to solve the inconsistency between the two tubes’ pointing directions. Second, temperatures of the mounting plate were used to be correlated with the daytime thermal deformation parameters to deduce the nighttime pointing directions when the landmarks were not available. Furthermore, the operational timetable for LMI was determined by analyzing the variations of navigation accuracy caused by the landmark observation interval and the sensor's integration time for landmarks. Analysis of about 9200 background images of 153 consecutive days from the housekeeping data were investigated to validate the proposed methods’ accuracy for LMI image navigation. Compared to the baseline algorithm, navigation accuracy has been improved on average from 2–10 pixels to 1 pixel. The FY-4A/LMI navigation system has been put into operation since May 1, 2018, which has been in normal service ever since.

In this paper, the copper coupled with steel under dry sliding are comparatively sdudied at 0.56 m s ^−1 and 3.36 m s ^−1 condition from the morphology, structure and composition of tribolayer of the copper. It is found that the wear rate of Cu at 3.36 m s ^−1 is twice that at 0.56 m s ^−1 , and the temperature of Cu block at 3.36 m s ^−1 (240 °C) is much higher than that at 0.56 m s ^−1 (75 °C). The results show that when the grinding speed is 0.56 m s ^−1 , the grain distortion occurs in the top area of the subsurface layer of Cu block. When the grinding speed is 3.36 m s ^−1 , the grain refinement zone appears below the subsurface layer of Cu block wear. The study further proves that the softening caused by friction heat occurs in the grain refinement zone, and a large number of softened metal copper tends to transfer to the opposite side. At the same time, the friction heat changes the mechanical and thermal deformation, material transfer and friction oxidation of the contact surface, which has a great influence on the dry sliding behavior of Cu.

Microarc oxidation (MAO) layers were prepared using 8g/L Na2SiO3 + 6g/L (NaPO3)6 + 4g/L Na2WO4 electrolyte with the addition of 2g/L Ti3SiC2/Ti3AlC2 particles under constant-current mode. The roughness, porosity, composition, surface/cross-sectional morphology, and frictional behavior of the prepared MAO layers were characterized by 3D real-color electron microscopy, scanning electron microscopy, X-ray energy spectrometry, X-ray diffractometry, and with a tribo-tester. The results showed that the addition of Ti3SiC2 and Ti3AlC2 to the electrolyte reduced the porosity of the prepared layers by 9% compared with that of the MAO layer without added particles. The addition of Ti3SiC2/Ti3AlC2 also reduced the friction coefficient and wear rate of the prepared layers by 35% compared with that of the MAO layer without added particles. It was found that the addition of Ti3AlC2 particles to the electrolyte resulted in the lowest porosity and the lowest wear volume.

Objectives As early prediction of severe illness and death for patients with coronavirus disease 2019 (COVID-19) is important, we aim to explore the clinical value of laboratory indicators in evaluating the progression and prognosis of patients with COVID-19.Design Retrospective cohort study.Setting Hospital-based study in China.Participants Adult patients with COVID-19 from December 15, 2019 to March 15, 2020.End point Disease severity and mortality.Methods Clinical data of 638 patients with COVID-19 were collected and compared between severe and non-severe groups. The predictive ability of laboratory indicators in disease progression and prognosis of COVID-19 was analysed using the receiver operating characteristic curve. The survival differences of COVID-19 patients with different levels of laboratory indicators were analysed utilising Kaplan-Meier analysis.Results 29.8% (190/638) of patients with COVID-19 progressed to severe. Compared with patients with no adverse events, C reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR) and D-dimer were significantly higher in severe patients with adverse events, such as acute myocardial injury, respiratory failure, acute kidney injury, mechanical ventilation, intensive care unit admission, multiple organ dysfunction syndromes and death (all p

Abstract Superoxide dismutase proteins (SODs) are antioxidant enzymes with important roles in abiotic stress responses. The SOD gene family has been systematically analyzed in many plants; however, it is still poorly understood in maize. Here, a bioinformatics analysis of maize SOD gene family was conducted by describing gene structure, conserved motifs, phylogenetic relationships, gene duplications, promoter cis-elements and GO annotations. In total, 13 SOD genes were identified in maize and five members were involved in segmental duplication. Phylogenetic analysis indicated that SODs from maize and other plants comprised two groups, which could be further classified into different subgroups, with most members in the same subgroup having the same subcellular localization. The ZmSOD promoters contained 2-10 stress-responsive cis-elements with different distributions. Heatmap analysis indicated that ZmSODs were expressed in most of the detected tissues and organs. The expression patterns of ZmSODs were investigated under drought and salt treatments by qRT-PCR, and most members were responsive to drought or salt stress, especially some ZmSODs with significant expression changes were identified, such as ZmCSD2 and ZmMSD2, suggesting the important roles of ZmSODs in abiotic stress responses. Our results provide an important basis for further functional study of ZmSODs in future study.

The key to battling the COVID-19 pandemic and its potential aftermath is to develop a variety of vaccines that are efficacious and safe, elicit lasting immunity, and cover a range of SARS-CoV-2 variants. Recombinant viral receptor-binding domains (RBDs) are safe vaccine candidates but often have limited efficacy due to the lack of virus-like immunogen display pattern. Here we have developed a novel virus-like nanoparticle (VLP) vaccine that displays 120 copies of SARS-CoV-2 RBD on its surface. This VLP-RBD vaccine mimics virus-based vaccines in immunogen display, which boosts its efficacy, while maintaining the safety of protein-based subunit vaccines. Compared to the RBD vaccine, the VLP-RBD vaccine induced five times more neutralizing antibodies in mice that efficiently blocked SARS-CoV-2 from attaching to its host receptor and potently neutralized the cell entry of variant SARS-CoV-2 strains, SARS-CoV-1, and SARS-CoV-1-related bat coronavirus. These neutralizing immune responses induced by the VLP-RBD vaccine did not wane during the two-month study period. Furthermore, the VLP-RBD vaccine effectively protected mice from SARS-CoV-2 challenge, dramatically reducing the development of clinical signs and pathological changes in immunized mice. The VLP-RBD vaccine provides one potentially effective solution to controlling the spread of SARS-CoV-2.

Accurate measurement of the radiative properties of clouds and aerosols is of great significance to global climate change and numerical weather prediction. The multi-angle polarization imager (MAPI) onboard the Fengyun-3 precipitation satellite, planned to be launched in 2023, will provide the multi-angle, multi-shortwave infrared (SWIR) channels and multi-polarization satellite observation of clouds and aerosols. MAPI operates in a non-sun-synchronized inclined orbit and provides images with a spatial resolution of 3 km (sub-satellite) and a swath of 700 km. The observation channels of the MAPI include 1030 nm, 1370 nm, and 1640 nm polarization channels and corresponding non-polarization channels, which provide observation information from 14 angles. In-flight radiometric and polarimetric calibration strategies are introduced, aiming to achieve radiometric accuracy of 5% and polarimetric accuracy of 2%. Simulation experiments show that the MAPI has some unique advantages of characterizing clouds and aerosols. For cloud observation, the polarization phase functions of the 1030 nm and 1640 nm around the scattering angle of a cloudbow show strong sensitivity to cloud droplet radius and effective variance. In addition, the polarized observation of the 1030 nm and 1640 nm has a higher content of information for aerosol than VIS-NIR. Additionally, the unique observation geometry of non-sun-synchronous orbits can provide more radiometric and polarization information with expanded scattering angles. Thus, the multi-angle polarization measurement of the new SWIR channel onboard Fengyun-3 can optimize cloud phase state identification and cloud microphysical parameter inversion, as well as the retrieval of aerosols. The results obtained from the simulations will provide support for the design of the next generation of polarized imagers of China.

Combating the COVID-19 pandemic requires potent and low-cost therapeutics. We identified a series of single-domain antibodies (i.e., nanobody), Nanosota-1, from a camelid nanobody phage display library. Structural data showed that Nanosota-1 bound to the oft-hidden receptor-binding domain (RBD) of SARS-CoV-2 spike protein, blocking viral receptor angiotensin-converting enzyme 2 (ACE2). The lead drug candidate possessing an Fc tag (Nanosota-1C-Fc) bound to SARS-CoV-2 RBD ~3000 times more tightly than ACE2 did and inhibited SARS-CoV-2 pseudovirus ~160 times more efficiently than ACE2 did. Administered at a single dose, Nanosota-1C-Fc demonstrated preventive and therapeutic efficacy against live SARS-CoV-2 infection in both hamster and mouse models. Unlike conventional antibodies, Nanosota-1C-Fc was produced at high yields in bacteria and had exceptional thermostability. Pharmacokinetic analysis of Nanosota-1C-Fc documented an excellent in vivo stability and a high tissue bioavailability. As effective and inexpensive drug candidates, Nanosota-1 may contribute to the battle against COVID-19.

S. miltiorrhiza is a perennial herb of the genus Salvia (Lamiaceae), which is an important medicinal plant for preventing and treating vascular dementia. The complete chloroplast genome sequence of Salvia miltiorrhiza was characterized from Illumina pair-end sequencing. The chloroplast genome of S. miltiorrhiza was 152,680 bp in length, containing a large single-copy region (LSC) of 84,104 bp, a small single-copy region (SSC) of 17,638 bp, and two inverted repeat (IR) regions of 25,469 bp. The overall GC content is 38.70%, while the correponding values of the LSC, SSC, and IR regions are 36.2%, 31.9%, and 43.2%, respectively. The genome contains 131 complete genes, including 86 protein-coding genes (62 protein-coding gene species), 37 tRNA genes (29 tRNA species) and 8 rRNA genes (4 rRNA species). The Neighbour-joining phylogenetic analysis showed that S. miltiorrhiza and Salvia przewalskii clustered together as sisters to other Salvia species.

Extracting accurate star centroids in the observed star images is one of the key problems for image navigation of the geosynchronous interferometric infrared sounder (GIIRS) of Fengyun-4A Satellite (FY-4A), the first scientific experimental satellite of the new generation of Chinese geostationary meteorological satellite Fengyun-4 series. Compared with star sensors which are widely used for star observation, it is challenging to detect the 2×2 star spot from the focused star images of GIIRS and calculate the star centroid in high precision. In this paper, we propose a star detection and centroiding method based on trajectory search and trajectory fitting. Since the launch of FY-4A in December 2016, our centroiding method has been tested in-orbit for over two years. The extensive experiments show that the star centroiding error of our method is less than 0.3 pixels, which makes an important contribution to image navigation of FY-4A.

Coronaviruses recognize a variety of receptors using different domains of their envelope-anchored spike protein. How these diverse receptor recognition patterns affect viral entry is unknown. Mouse hepatitis coronavirus (MHV) is the only known coronavirus that uses the N-terminal domain (NTD) of its spike to recognize a protein receptor, CEACAM1a. Here we determined the cryo-EM structure of MHV spike complexed with mouse CEACAM1a. The trimeric spike contains three receptor-binding S1 heads sitting on top of a trimeric membrane-fusion S2 stalk. Three receptor molecules bind to the sides of the spike trimer, where three NTDs are located. Receptor binding induces structural changes in the spike, weakening the interactions between S1 and S2. Using protease sensitivity and negative-stain EM analyses, we further showed that after protease treatment of the spike, receptor binding facilitated the dissociation of S1 from S2, allowing S2 to transition from pre-fusion to post-fusion conformation. Together these results reveal a new role of receptor binding in MHV entry: in addition to its well-characterized role in viral attachment to host cells, receptor binding also induces the conformational change of the spike and hence the fusion of viral and host membranes. Our study provides new mechanistic insight into coronavirus entry and highlights the diverse entry mechanisms used by different viruses.

Seven coronaviruses (CoVs) have been isolated from humans so far. Among them, three emerging pathogenic CoVs, including severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and a newly identified CoV (2019-nCoV), once caused or continue to cause severe infections in humans, posing significant threats to global public health. SARS-CoV infection in humans (with about 10% case fatality rate) was first reported from China in 2002, while MERS-CoV infection in humans (with about 34.4% case fatality rate) was first reported from Saudi Arabia in June 2012. 2019-nCoV was first reported from China in December 2019, and is currently infecting more than 70000 people (with about 2.7% case fatality rate). Both SARS-CoV and MERS-CoV are zoonotic viruses, using bats as their natural reservoirs, and then transmitting through intermediate hosts, leading to human infections. Nevertheless, the intermediate host for 2019-nCoV is still under investigation and the vaccines against this new CoV have not been available. Although a variety of vaccines have been developed against infections of SARS-CoV and MERS-CoV, none of them has been approved for use in humans. In this review, we have described the structure and function of key proteins of emerging human CoVs, overviewed the current vaccine types to be developed against SARS-CoV and MERS-CoV, and summarized recent advances in subunit vaccines against these two pathogenic human CoVs. These subunit vaccines are introduced on the basis of full-length spike (S) protein, receptor-binding domain (RBD), non-RBD S protein fragments, and non-S structural proteins, and the potential factors affecting these subunit vaccines are also illustrated. Overall, this review will be helpful for rapid design and development of vaccines against the new 2019-nCoV and any future CoVs with pandemic potential. This review was written for the topic of Antivirals for Emerging Viruses: Vaccines and Therapeutics in the Virology section of Frontiers in Microbiology.

Plasma electrolytic oxidation treatment of 6061 Al alloy was carried out in a sodium silicate and sodium hydroxide alkaline electrolyte containing different concentrations of cerium nitrate (Ce (NO _3 ) _3 ) under constant current mode. The effects of Ce (NO _3 ) _3 concentration on the roughness, cross section and surface morphology, composition and phase composition, adhesion force and corrosion resistance of the prepared layer were studied by means of true color microscope, scanning electron microscope, x-ray energy spectrometer, x-ray diffractometer, micrometer scratcher and electrochemical workstation. The results show that with the increase of Ce(NO _3 ) _3 concentration in the electrolyte, the thickness of the plasma electrolytic oxidation layer increases gradually, and the micropores and cracks increase, and the roughness increases first and then decreases. The plasma electrolytic oxidation layers under different concentrations of Ce (NO _3 ) _3 are mainly composed of α -Al _2 O _3 , γ -Al _2 O _3 and a small amount of Al _2 SiO _5 . The Ce element in the layer is mainly present in the form of a mixture of Ce(OH) _4 , CeO _2 and Ce _2 O _3 .The increase of Ce (NO _3 ) _3 concentration reduces the binding strength between the plasma electrolytic oxidation layer and the matrix, increases the self-corrosion potential, decreases the self-corrosion current, and weakens the corrosion resistance. The layer with a concentration of 0.25 g l ^−1 Ce (NO _3 ) _3 has less micropores and cracks, and has the better compactness. The bonding strength between the layer and the substrate is 27 N, the corrosion current density is 3.42 × 10 ^−9 A cm ^−2 and corrosion potential is −0.72 V, the best bonding strength and corrosion resistance is presented.

The powder pack cementation was used for niobiumizing treatment of GCr15 pin steel, and the effects of different rare earth types and contents on microstructure and properties of niobiumizing layer were investigated. Optical microscope, x-ray diffractometer, scanning electron microscope, electrochemical workstation and ball-disk friction wear machine were used to observe the structure and evaluate the properties of the niobiumizing layer. And the kinetics and mechanism of niobiumizing layer with rare earths was explored. The results show that a dense and continuous niobiumizing layer formed under different rare earth types and contents condition. The layer is 3 μ m-15 μ m in average thickness, 1800 HV _0.2 -2500 HV _0.2 in average microhardness and is composed of NbC _x compound and α -Fe. Comprehensive comparison, La _2 O _3 can significantly improve the wear and corrosion resistance of the niobiumizing layer. The self-corrosion potential of niobiumizing layer is −0.5759 V, the corrosion current density is 5.2365 × 10 ^−7 A cm ^−2 , and the average friction coefficient is 0.385 when La _2 O _3 is added at 2%.

Lightweight and flexible energy storage devices are needed to persistently power wearable devices. Here the authors employ metallized carbon fabrics as hosts for sulfur and lithium to achieve flexibility, electrochemical stability and high energy density in a lithium-sulfur battery.

Star observation can be used for the image navigation of certain instruments aboard the three-axis stabilized geostationary satellites. How to extract the accurate star centroids in the observed star images is one of the key problems. In this paper, a high precision star centroid detection method is proposed for the advanced geosynchronous radiation imager (AGRI) of Fengyun-4A (FY-4A), the first experimental satellite of the new generation of Chinese geostationary meteorological satellites FY-4 series. Different from star sensors which are deliberately defocused with relatively large star spot, AGRI is focused for the purpose of earth observation, making it challenging to extract accurate star centroids. To solve the problem, we take the advantage of continuous observing and improve the precision of star centroiding by trajectory fitting and energy response curve fitting. Extensive experiments have been performed on simulated star images and the actual observation data of AGRI aboard FY-4A over ten months in-orbit tests. Experimental results show that the proposed method can accurately extract star centroids with the error less than 0.3 pixels, laying a solid foundation for image navigation of FY-4A.

Objective This study was performed to investigate whether a definite correlation exists between alteration of blood biochemical parameters and immunosuppressive therapies in patients with inflammatory bowel disease (IBD). Methods A comprehensive search of PubMed, EMBASE, MEDLINE, and the Cochrane Library was conducted. Data on alterations in white blood cells, platelets, hemoglobin, serum creatinine, and liver enzymes in patients with IBD treated with immunomodulators were extracted. Results Data from 1141 patients were included. The relative risk (RR) of leukopenia was significantly higher in the immunosuppressive therapies group than in the placebo group (RR, 12.91; 95% confidence interval [CI], 5.28–31.57). A statistically significant risk of leukocytosis during immunosuppressive therapies was observed (RR, 1.53; 95% CI, 1.05–2.23). Patients taking immunomodulators had increased risks of serum creatinine elevation (RR, 10.68; 95% CI, 2.07–55.12) and serum aminotransferase elevation (RR, 3.18; 95% CI, 1.24–8.17). Conclusion Immunosuppressive therapies might have an impact on variations in blood biochemical parameters in patients with IBD. Although the conclusion regarding leukopenia was reliable in this study, some confounding factors might reduce the reliability of the conclusions about leukocytosis, creatinine elevation, and aminotransferase elevation. Close monitoring is recommended during immunosuppressive therapies for IBD.

As cell-invading molecular machinery, coronavirus spike proteins pose an evolutionary conundrum due to their high divergence. In this study, we determined the cryo-EM structure of avian infectious bronchitis coronavirus (IBV) spike protein from the γ-genus. The trimeric IBV spike ectodomain contains three receptor-binding S1 heads and a trimeric membrane-fusion S2 stalk. While IBV S2 is structurally similar to those from the other genera, IBV S1 possesses structural features that are unique to different other genera, thereby bridging these diverse spikes into an evolutionary spectrum. Specifically, among different genera, the two domains of S1, the N-terminal domain (S1-NTD) and C-terminal domain (S1-CTD), diverge from simpler tertiary structures and quaternary packing to more complex ones, leading to different functions of the spikes in receptor usage and membrane fusion. Based on the above structural and functional comparisons, we propose that the evolutionary spectrum of coronavirus spikes follows the order of α-, δ-, γ-, and β-genus. This study has provided insight into the evolutionary relationships among coronavirus spikes and deepened our understanding of their structural and functional diversity.

Aviation induced cloud termed contrail plays a more and more important role in the climate change, which makes a significant contribution to anthropogenic climate forcing through impacting the coverage of cirrus in the intersection of troposphere and stratosphere. In this paper, we propose one novel automatic contrail detecting method based on Himawari-8 stationary satellite imagery and two kinds of potential contrail coverage (PCC1 and PCC2) from contrail parameterization in ECHAM4 and HadGEM2. In addition, we propose one new climatological index called contrail occurrence and persistence (COP). According to the algorithm identification (AI) and artificial visual inspection (AVI), COP measured from Himawari-8 stationary satellite imagery is related to upper tropospheric relative humidity over ice (RHI) computed with the ECMWF reanalysis data by simple linear regression. Similarly, we compared the linear correlation between COP and PCCs fractions and found that PCC1 has better correspondence with COP than PCC2.

A highly regioselective SN2' Mitsunobu reaction between Morita–Baylis–Hillman (MBH) alcohols, azodicarboxylates, and triphenylphosphine is developed, which provides an easy access to α-alkylidene-β-hydrazino acid derivatives in high yields and good stereoselectivity. This reaction represents the first direct transformation of MBH alcohols into hydrazines.

Retrieval of ice cloud properties using passive terahertz wave radiometer from space has gained increasing attention currently. A multi-channel regression inversion method for passive remote sensing of ice water path (IWP) in the terahertz band is presented. The characteristics of the upward terahertz radiation in the clear-sky and cloudy-sky are first analyzed using the Atmospheric Radiative Transfer Simulator (ARTS). Nine representative center frequencies with different offsets are selected to study the changes of terahertz radiation caused by microphysical parameters of ice clouds. Then, multiple linear regression method is applied to the inversion of IWP. Combinations of different channels are selected for regression to eliminate the influence of other factors (i.e., particle size and cloud height). The optimal fitting equation are obtained by the stepwise regression method using two oxygen absorption channels (118.75 ± 1.1 GHz, 118.75 ± 3.0 GHz), two water vapor absorption channels (183.31 ± 1.0 GHz, 183.31 ± 7.0 GHz), and two window channels (243.20 ± 2.5 GHz, 874.4 ± 6.0 GHz). Finally, the errors of the proposed inversion method are evaluated. The simulation results show that the absolute errors of this method for the low IWP cases are below 7 g/m2, and the relative errors for the high IWP cases are generally ranging from 10 to 30%, indicating that the multi-channel regression inversion method can achieve satisfactory accuracy.

Tumor necrosis factor (TNF) receptor-associated factor 5 (TRAF5) is a key mediator of TNF receptor superfamily members and is important in both T helper (Th) cell immunity and the regulation of multiple signaling pathways. To clarify TRAF5’s influence on inflammatory bowel diseases (IBDs), we investigated TRAF5 deficiency’s effect on dextran sulfate sodium- (DSS-) induced colitis. Colitis was induced in TRAF5 knockout (KO) mice and their wild-type (WT) littermates by administering 3% DSS orally for 7 days. The mice were then sacrificed, and their colons were removed. Our data suggested that KO mice were more susceptible to DSS-induced colitis. TRAF5 deficiency significantly enhanced IFN-γ, IL-4, and IL-17a mRNA and protein levels in the colons of DSS-fed mice, and the mRNA expression of T-bet and GATA-3 was also markedly elevated. However, ROR-α and ROR-γt mRNA levels did not differ between DSS-induced KO and WT mice. Flow cytometry showed increased frequencies of Th2 and IFN-γ/IL-17a-coproducing CD4+ T cells in the colons of DSS-induced KO mice. Additionally, TRAF5 deficiency significantly enhanced the activation of NF-κB in CD4+ T cells after DSS administration. These results indicated that TRAF5 deficiency significantly aggravated DSS-induced colitis, most likely by regulating Th cell-mediated inflammation.

In the title compound, C27H27Cl2N7O4S, the amide groups bearing the N—S group and the tert-butyl group have s–trans conformations. The steric size of the tert-butyl and [(6-chloro-3-pyridyl)methyl]imidazolidin-2-ylidene groups cause the 2-chlorobenzoyl group and the benzyol group to be directed away from one another, forming a dihedral angle of 60.62 (17)°. The central N—N bond adopts a gauche conformation with a C—N—N—C torsion angle of −79.1 (2)°.

Byline: Meng. Xianyu, Bi. Zhenggang, Shang. Jian, Lu. Laijin Background and Aims: It is important to distinguish between motor and sensory fascicles of the peripheral nerves for nerve alignment in [...]