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Oxidized low‐density lipoprotein (oxLDL), a key component in atherosclerosis and hyperlipidemia, is a risk factor for atherothrombosis in dyslipidemia, yet its mechanism is poorly understood. In this study, we used oxLDL‐induced human aortic endothelial cells (HAECs) and high‐fat diet (HFD)‐fed mice as a hyperlipidemia model. Phosphatidylserine (PS) exposure, cytosolic Ca2+, reactive oxygen species (ROS), and lipid peroxidation were measured by flow cytometer. TMEM16F expression was detected by immunofluorescence, western blot, and reverse transcription polymerase chain reaction. Procoagulant activity (PCA) was measured by coagulation time, intrinsic/extrinsic factor Xase, and thrombin generation. We found that oxLDL‐induced PS exposure and the corresponding PCA of HAECs were increased significantly compared with control, which could be inhibited over 90% by lactadherin. Importantly, TMEM16F expression in oxLDL‐induced HAECs was upregulated by enhanced intracellular Ca2+ concentration, ROS, and lipid peroxidation, which led to PS exposure. Meanwhile, the knockdown of TMEM16F by short hairpin RNA significantly inhibited PS exposure in oxLDL‐induced HAECs. Moreover, we observed that HFD‐fed mice dramatically increased the progress of thrombus formation and accompanied upregulated TMEM16F expression by thromboelastography analysis, FeCl3‐induced carotid artery thrombosis model, and western blot. Collectively, these results demonstrate that TMEM16F‐mediated PS exposure may contribute to prothrombotic status under hyperlipidemic conditions, which may serve as a novel therapeutic target for the prevention of thrombosis in hyperlipidemia. Highlights: Oxidized low‐density lipoproteins (oxLDL) could increase phosphatidylserine (PS) exposure and procoagulant activity (PCA) of human aortic endothelial cells (HAECs) in a TMEM16F‐dependent manner.Increased intracellular Ca2+ and oxidative stress may contribute to TMEM16F‐mediated phospholipid scrambling.Hyperlipidemia exhibited a prothrombotic phenotype, which was likely related to TMEM16F‐mediated PS exposure on HAECs.Inhibition of TMEM16F or PS could be a novel therapeutic strategy to alleviate the thromboembolic complication of hyperlipidemia. [ABSTRACT FROM AUTHOR]

Lidar observations of metal layers play a significant role in research on the chemistry and dynamics of the mesosphere and lower thermosphere. This work reports on Fe lidar observations conducted in Beijing and Mohe. Utilizing the same laser emission system, a 1064 nm seed laser was injected into an Nd: YAG laser to generate a single longitudinal-mode pulse 532 nm laser, which pumped a dye laser to produce a 572 nm laser. The 572 nm laser and the remaining 1064 nm fundamental frequency laser passed through a sum–frequency module to generate a 372 nm laser to detect the Fe layer. According to a total of 52.6 h of observations for 10 nights in Beijing, the Fe layer has an average column density of 1.24 × 1010 cm−2, an RMS width of 4.4 km and a centroid altitude of 89.4 km. In Mohe, observed for 16 nights and a total of 91.5 h, the Fe layer has an average column density of 1.08 × 1010 cm−2, an RMS width of 4.6 km and a centroid altitude of 89.5 km. The probability of the occurrence of sporadic Fe layers was 42.4% in Beijing and 29.4% in Mohe. Compared to simultaneously observed Na layers, the occurrence probabilities of sporadic Fe layers were higher than those of sporadic Na layers in both stations. Based on the two cases observed in Beijing, it is conjectured that the formation mechanism of sporadic metal layers above approximately 100 km has a more significant influence on sporadic Fe layers than on sporadic Na layers. The lower thermospheric Fe layers with densities significantly larger than those of the main layer were observed during two nights in Mohe. This work contributes to the refinement of the global distribution of Fe layers and provides abundant observational data for the modeling and study of the metal layers. [ABSTRACT FROM AUTHOR]

Resonance fluorescence scattering is the physical mechanism with which lidar detects atmospheric metal layers. The resonance fluorescence scattering cross section is an important parameter for lidar data processing. In this work, the resonance fluorescence backscattering cross sections of most detectable metal atoms and ions in the atmosphere were calculated. The calculated maximum backscattering cross section of Na at the D2 line is 7.38 × 10−17 m2/sr; K at the D1 line is 7.37 × 10−17 m2/sr; Fe at the 372 nm line is 7.53 × 10−18 m2/sr; Fe at the 374 nm line is 6.98 × 10−18 m2/sr; Fe at the 386 nm line is 3.75 × 10−18 m2/sr; Ni at the 337 nm line is 4.05 × 10−18 m2/sr; and Ni at the 341 nm line is 2.05 × 10−17 m2/sr; Ca is 3.06 × 10−16 m2/sr; Ca+ is 1.12 × 10−16 m2/sr. The influence of the laser linewidth on the effective scattering cross section was discussed. If the laser linewidth is lower than 2 GHz to detect Na, the laser center frequency locked at the D2a line is a better option than the D2 line in order to obtain greater signals. If an unlocked lidar is used to detect Na, the frequency at D2a should be used as the laser center frequency when the effective scattering cross section of Na was calculated, because the absorption cross section of Na atom has two local maxima. This work proposes a quantifiable comparative method for assessing the observation difficulty of different metal particles by comparing their relative uncertainties in lidar observation. It is assumed that under the same observation conditions, the detectability of different metal atoms and ions is compared. Using Na as a basis for comparison, the relative uncertainty of Ni at 337 nm is the highest, about a factor of 21 larger than that of Na, indicating that it is the most difficult to be detected. The purpose of this work is to present a quantifiable comparison method for the detection difficulty of the metal particles by lidar in the middle and upper atmosphere, which has great significance for the design of the lidar system. [ABSTRACT FROM AUTHOR]

Earth‐abundant transition metal catalysis has emerged as an important alternative to noble transition metal catalysis in hydrogenation reactions. However, there has been no Earth‐abundant transition metal catalyzed hydrogenation of thioamides reported so far, presumably due to the poisoning of catalysts by sulfur‐containing molecules. Herein, we described the first manganese‐catalyzed hydrogenative desulfurization of thioamides to amines or imines. The key to success is the use of MnBr(CO)5 instead of commonly‐employed pincer‐manganese catalysts, together with simple NEt3 and CuBr. This protocol features excellent selectivity on sole cleavage of the C=S bond of thioamides, in contrast to the only known Ru‐catalyzed hydrogenation of thioamides, and unprecedented chemo‐selectivity tolerating vulnerable functional groups such as nitrile, ketone, aldehyde, ester, sulfone, nitro, olefin, alkyne and heterocycle, which are usually susceptible to common hydride‐type reductive protocols. [ABSTRACT FROM AUTHOR]

Earth‐abundant transition metal catalysis has emerged as an important alternative to noble transition metal catalysis in hydrogenation reactions. However, there has been no Earth‐abundant transition metal catalyzed hydrogenation of thioamides reported so far, presumably due to the poisoning of catalysts by sulfur‐containing molecules. Herein, we described the first manganese‐catalyzed hydrogenative desulfurization of thioamides to amines or imines. The key to success is the use of MnBr(CO)5 instead of commonly‐employed pincer‐manganese catalysts, together with simple NEt3 and CuBr. This protocol features excellent selectivity on sole cleavage of the C=S bond of thioamides, in contrast to the only known Ru‐catalyzed hydrogenation of thioamides, and unprecedented chemo‐selectivity tolerating vulnerable functional groups such as nitrile, ketone, aldehyde, ester, sulfone, nitro, olefin, alkyne and heterocycle, which are usually susceptible to common hydride‐type reductive protocols. [ABSTRACT FROM AUTHOR]

The degradation of the electrical contact in a gas insulated switchgear (GIS) is closely related to overheating at the contact. However, the disconnector contact is one of the hot contacts in GIS. Therefore, in this paper, the finite element method was used to solve the three-dimensional multiphysics coupling temperature rise field and flow field in the Single Phase in One Tank (SPIOT) type GIS disconnector under different operating conditions. From the perspective of temperature rise field and flow field, this paper analyzed the temperature rise characteristics under different working conditions and explored the feasibility of the direct application of air, CO2 and C4F7N/CO2 mixed gas to an electrical device. The disconnector temperature rise experiment platform was then built to verify the simulation. The results showed that the temperature rise field and the flow field distribution were similar in four gas environments. SF6 gas had the smallest temperature rise, followed by C4F7N/CO2 mixed gas, and the temperature rise of CO2 and air was relatively large. Therefore, from the perspective of the temperature rise field and flow field, it was feasible to directly apply C4F7N/CO2 mixed gas to an electrical device in order to meet insulation requirements. [ABSTRACT FROM AUTHOR]

The link between serum uric acid (SUA) and the risk of venous thromboembolism (VTE) is well established. Recent data suggested a causative role of UA in endothelial cells (ECs) dysfunction. However, the molecular mechanism of high UA on thrombogenesis is unknown. We investigate whether high UA induce phosphatidylserine (PS) externalization and microparticle (MP) shedding in cultured EC, and contribute to UA‐induced hypercoagulable state. In the present study, we demonstrate that UA induces PS exposure and EMP release of EC in a concentration‐ and time‐dependent manner, which enhances the procoagulant activity (PCA) of EC and inhibited over 90% by lactadherin in vitro. Furthermore, hyperuricemic rat model was used to evaluate the development of thrombi following by flow stasis in the inferior vena cava (IVC). Hyperuricemia group is more likely to form large and hard thrombi compared with control. Importantly, we found that TMEM16F expression is significantly upregulated in UA‐treated EC, which is crucial for UA‐induced PS exposure and MP formation. Additionally, UA increases the generation of reactive oxygen species (ROS), lipid peroxidation, and cytosolic Ca2+ concentration in EC, which might contribute to increased TMEM16F expression. Using confocal microscopy, we also observed disruption of the actin cytoskeleton, suggesting that depolymerization of actin filaments might be required for TMEM16F activation and followed by PS exposure and membrane blebbing in UA‐treated EC. Our results demonstrate a thrombotic role of EC in hyperuricemia through TMEM16F‐mediated PS exposure and MPs release. [ABSTRACT FROM AUTHOR]

Vacuum circuit breaker is a kind of power equipment widely used in the power system. It is developing toward the direction of high voltage and high current. How to design the contact to maximize the interrupting capacity of the contact system has been conducted by scholars. In this paper, the magnetic field simulation model of contact system is established, the magnetic field distribution characteristics of vacuum interrupters are studied, and the distribution characteristics of the magnetic field in the half cycle of the cup‐shaped axial magnetic field contact system are simulated and analyzed. On this basis, by changing the contact structure parameters, the effects of the number of slots in the cup, the slot angle, the center hole of the contacts, and the length of the slots on the distribution of the axial magnetic field were obtained. The results show that grooving the contact can reduce the eddy current, but it has a limited effect on reducing residual magnetic field. The increase of slot angle of contact cup can effectively reduce the residual axial magnetic field at the zero current moment and the axial magnetic field intensity at the peak current moment. Based on the above research results, a new embedded axial magnetic contact system with 12 slots embedded magnetic ring and reverse contact cup is designed. The embedded magnetic ring and reverse spiral slot increase the axial magnetic field at the peak current moment and reduce the residual axial magnetic field at the zero current moment. Finally, the characteristics of the magnetic field have been improved significantly compared with the magnetic field of traditional cup‐shaped axial magnetic field contact. © 2020 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Electric vehicles with hub motors have integrated the motor into the wheel, which increase the unsprung mass of the vehicle, and intensifies the vibration of the underspring components. The motor excitation during driving also intensifies the wheel vibration. The coupling effect between the two makes the performance of electric vehicles deteriorate. The article employed a disc-type permanent-magnet motor as the hub motor, taking into consideration the increase in sprung mass caused by the hub motor and the adverse effects of vertical vibration from motor excitation. Based on random road-surface excitation, and considering the secondary excitation caused by wheel motor drive and vehicle-road coupling, a coupled-dynamics model of a semi-active-suspension vehicle-road system for vertical vehicle motion is investigated under multiple excitations. Using body acceleration, suspension deflection, and dynamic tire load as evaluation indicators, a BP neural network PID controller based on the sparrow search algorithm optimization is proposed for the semi-active-suspension system. Compared with PID control and particle swarm optimization (PSO-BPNN-PID), the research findings indicate that the optimized semi-active suspension significantly improves the ride comfort of hub-motor electric vehicles, and meets the requirements for control performance under different vehicle driving conditions. [ABSTRACT FROM AUTHOR]

In March 2020, an all-solid-state dual-wavelength narrow-band lidar system was deployed. A total of 226 nights spanning from March 2020 to July 2022 were employed in order to investigate the seasonal variations of calcium atoms and ions in the mesosphere over Beijing (40.41°N, 116.01°E). The Ca+ layer shows general annual variation, while a semiannual variation is observed on the Ca layer. The calcium atomic column densities ranged from 2.0 × 106 to 1.1 × 108 cm−2, and the calcium ion column densities ranged from 1.6 × 106 to 4.2 × 108 cm−2. The mean centroid heights of Ca+ and Ca are 98.6 km and 93.0 km, respectively, and the centroid heights of Ca+ and Ca are mostly influenced by annual variations. The seasonal variation in the Ca+ and Ca layers in Beijing exhibits similarities to that of Kühlungsborn (54°N). While the peak density of Ca+ in Beijing are similar to those observed in Kühlungsborn, the peak density of the Ca layer in Beijing is about half of that reported in the Ca layer at 54°N. We provide an explanation for the disparities in the column abundance and centroid altitude of the Ca layer between Yanqing and Kühlungsborn, discussing variations in neutralization among different metal ions. [ABSTRACT FROM AUTHOR]

To reduce the size of spectral data, compressive sensing imaging systems are developed to sample fewer measurements than the Nyquist‐rate ones, from which the original data can be recovered by the optimisation model and algorithm. However, this is not a cheap option for the case where the real‐time acquisition of spectral information is required. To solve this problem, the authors propose a novel sensing approach for spectral features by combining the sampling, recovery and feature extraction. Inspired by the spectral feature representation, the sampling (sensing) matrix is designed from the training spectral samples to sense the spectral features of the imaging scene, which can be utilised for classification and recognition directly. Besides, the physical realisation of the sensing matrix for compressive spectral imaging systems is demonstrated by designing new modulation patterns of the digital micro‐mirror device. The experimental results on real spectral data show the feasibility of the proposed scheme and the robustness to the quantisation error and the measurement noise. Moreover, the proposed sensing approach can reduce the cost of computation and time greatly by removing the sparse recovery and feature extraction.. [ABSTRACT FROM AUTHOR]

Compressive sensing (CS) theory enables single‐pixel compressive imaging (SPCI) popular in optical remote sensing imaging, since single‐pixel imager not only realises the acquisition and recovery of sparse images at the sampling rates significantly below the classical Nyquist rate, but also makes use of special detectors to improve sensitivity, dynamic range, spectral range and so on. However, its requirement of static imaging condition for the time‐sequential measurements makes it difficult to apply in remote sensing, since the imaging platform is always in motion relative to the imaging scene. In this study, the authors develop a new method for SPCI on moving platform in optical remote sensing. Instead of ignoring the motion during sampling, the proposed method first builds the compressive sampling model based on motion compensation during sampling, and then reconstructs the image by frame‐by‐frame recovery method and joint recovery method, respectively, in the framework of CS theory, where the recovery condition is also analysed. To validate the basic principle and the physical feasibility of motion compensation, the authors implement the numerical simulations and optical experiments, where different conditions are exploited sufficiently. In addition, the proposed method for SPCI can be also extended into other applications, such as 360° annular imaging, multi‐pixel compressive imaging as well as super‐resolution imaging. [ABSTRACT FROM AUTHOR]

Based on the resonance fluorescence scattering mechanism, a narrowband sodium (Na) lidar can measure temperature and wind in the mesosphere and lower thermosphere (MLT) region. By using a narrowband spectral filter, background light noise during the day can be suppressed, allowing for continuous observations. To obtain full-diurnal-cycle temperature and wind measurement results, a complex and precise retrieval process is required, along with necessary corrections to minimize measurement errors. This paper introduces the design of a data acquisition unit for three frequencies in three directions of the Na lidar system in the Chinese Meridian Project (Phase II) and investigates the calibration and retrieval methods for obtaining diurnal temperature and horizontal wind in the MLT region, using a Na Doppler lidar with Faraday anomalous dispersion optical filter (FADOF). Furthermore, these methods are applied to observations conducted by a Na lidar in Beijing, China. The wind and temperature results over full diurnal cycles obtained from the all-solid-state Na Doppler lidar are reported for the first time and compared with temperature measurements from satellite, as well as wind observations from a meteor radar. The comparison demonstrates a reasonable agreement between the results, indicating the rationality of the lidar-retrieved results and the feasibility and effectiveness of the data correction and retrieval method. [ABSTRACT FROM AUTHOR]

Convolutional neural networks have proven to be highly successful in applications such as image classification, object tracking, and many other tasks based on 2D inputs. Recently, researchers have started to apply convolutional neural networks to video classification, which constitutes a 3D input and requires far larger amounts of memory and much more computation. FFT based methods can reduce the amount of computation, but this generally comes at the cost of an increased memory requirement. On the other hand, the Winograd Minimal Filtering Algorithm (WMFA) can reduce the number of operations required and thus can speed up the computation, without increasing the required memory. This strategy was shown to be successful for 2D neural networks. We implement the algorithm for 3D convolutional neural networks and apply it to a popular 3D convolutional neural network which is used to classify videos and compare it to cuDNN. For our highly optimized implementation of the algorithm, we observe a twofold speedup for most of the 3D convolution layers of our test network compared to the cuDNN version. [ABSTRACT FROM AUTHOR]

Heat accumulation has emerged as a critical issue that affects the performance and reliability of modern electronic devices in their evolving toward miniaturization, high power density and high integration. The application of thermal interface materials (TIMs) as a thermal management strategy is commonly employed to tackle this problem. Herein, we report the development and characterization of highly thermally conductive but electrically insulating Cu@Al 2 O 3 /epoxy composites. Stemming from the excellent thermal conductivity of Cu, the Cu@Al 2 O 3 /epoxy composites exhibit thermal conductivity of 1.32 W/m·K at 10 vol% filler content, which is nearly 7 times higher than that of the epoxy resin. Simultaneously, the Cu@Al 2 O 3 /epoxy composites still retain a high electrical resistivity of 2.3 × 1013 Ω·cm, which is 6 orders of magnitude greater than that of Cu/epoxy composites without Al 2 O 3 barrier layers, because the dense nanoscale insulating Al 2 O 3 shell effectively inhibits the electron transfer. In addition, the Cu@Al 2 O 3 /epoxy composites possess lower dielectric constant and dielectric loss, and better mechanical properties than those of Cu/epoxy composites. [Display omitted] • Core-shell Cu@Al 2 O 3 particles were rationally designed and prepared by a simple and scalable solution-based process. • Cu@Al 2 O 3 /epoxy composites were fabricated as thermal interface materials for thermal management application. • Enhanced thermal conductivity and high electrical insulation was achieved by Cu@Al 2 O 3 /epoxy at a low filler content. • Cu@Al 2 O 3 /epoxy composites possess better dielectric and mechanical performances than those of Cu/epoxy composites. [ABSTRACT FROM AUTHOR]

A double-laser-beam lidar was successfully developed in 2010 to measure the K layer over Yanqing County, Beijing (40.5°N, 116.2°E). Comprehensive statistical analyses of sporadic K (Ks) layer parameters were conducted using two years of lidar data, and the parameters of the Ks layers and their distribution obtained by the analyses are described. The seasonal distribution of Ks occurrence was obtained, with two maxima observed in January and July, respectively. The seasonal distributions of sporadic E (Es) occurrence over Beijing differ from those of Ks occurrence. However, good correlations between Es and Ks in case by case study were found. We also found that four Ks events with peak altitudes lower than 90 km were associated with large and sharp temperature increases in five comparative examples. [ABSTRACT FROM AUTHOR]

Abstract: Silica-coated ultrafine diamond (UFD/SiO2) composites were prepared, which were core/shell structures with amorphous silica shell of approximately 5nm thickness. Contrasting to the pristine UFDs, the dispersion stability of the UFD/SiO2 composites was improved greatly in the multi-component inorganic salts aqueous solution, and the chemical compositions of the ceramic matrix were introduced by multi-component inorganic salts. Meanwhile, the oxidation resistance temperature of the coated UFDs was also increased by around 101.0°C. Furthermore, by using the polyacrylamide gel method and hot-press sintering process, ceramic composites were fabricated with the UFD/SiO2 aqueous suspension containing multi-component inorganic salts. The results indicated that the UFDs coated with silica could be dispersed uniformly in ceramic matrix, where no obvious UFD agglomerates were observed. [Copyright &y& Elsevier]

Optimization of the mechanical properties is necessary in the applications of electrospun nanofibrous matrices. In this work, mechanical reinforcement of electrospun nanofiber membranes of water-soluble polymer by the incorporation of commercial nanodiamonds (NDs) was studied. Through an ND/poly(vinyl alcohol) (ND/PVA) model system, it is demonstrated that 155% improvement of Young's modulus, 89% increase in tensile strength, and 336% elevation in energy to break are achieved by the addition of only 2 wt% ND. Fourier transform infrared spectroscopy results suggest the existence of molecular interactions between NDs and PVA matrix, which contributes to the effective load transfer from the polymer matrix to the fillers. However, higher level of ND addition (>2 wt%) aggravates the agglomeration of nanofillers in PVA matrix and offsets the reinforcing effect, as ND agglomerates may act as flaws in composite nanofibers. Furthermore, NDs have optimizing effect on the morphology of ND/PVA nanofibers through increasing the conductivity of the electrospinning solution. Therefore, ND nanofillers possess the potential to improve the mechanical performance of water-soluble polymer-based nanofiber membranes. POLYM. COMPOS., 34:1735-1744, 2013. © 2013 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

[Display omitted] • Core-shell structured Cu@BaTiO 3 particles were prepared. • Cu@BaTiO 3 /epoxy composites were fabricated as thermal interface materials. • The thermal conductivity was enhanced and high electrical insulation was retained for Cu@BaTiO 3 /epoxy composites. The application of polymer for thermal interface materials is limited by its low thermal conductivity. In this work, barium titanate coated Cu core–shell particles were prepared and then employed as thermal conductive fillers to reinforce epoxy matrix. The results indicate that thermal conductivity of the Cu@BaTiO 3 /epoxy composites reaches 1.09 W m-1K−1 at 10 vol% loading, achieving 580% elevation on neat epoxy matrix. Meanwhile, the composites retain high electrical insulation (7.90 × 1013 Ω·cm) due to the existence of insulative BaTiO 3 layer on Cu surface. This study will provide a novel insight of the design of functionalized core–shell thermal conductive fillers and construction of high-performance thermal interface materials. [ABSTRACT FROM AUTHOR]

Abstract: As the development of the technology for radar target recognition, missile target automatic recognition has received considerable attention in recent years. Missile target, compared with the plane target, is hard to recognize for its smallness, feebleness and maneuver. In this paper, a new recognition method based on radar image time-series, which can significantly reduce the recognition time and classification error, is proposed. The image time-series are produced by range instantaneous Doppler imaging algorithm firstly, and then cross-range scaling of the images is processed. In particular, the inertia ratio, extracted from the obtained image time-series, is introduced to distinguish the missile from decoys. Furthermore, the effectiveness of this method is demonstrated by application to simulated data and it has been shown that this method has the potential to be used in a number of real-time applications. [Copyright &y& Elsevier]

Regulating the composition and microstructure of nanomaterials is a major challenge in the development of high-performance materials for electromagnetic wave (EMW) absorption. This paper introduces a new lightweight EMW-absorbing material Co@N/C with a yolk–shell structure and compositions of ferromagnetic metal and carbon materials. The minimum reflection loss (RL min) of the as-designed Co@N/C nanospheres with a filler loading of 25 wt% reaches −67.68 dB and the effective absorption bandwidth of a 1.9 mm thickness is 5.3 GHz. The exceptional absorption performance of the EMW absorption is primarily achieved through the synergistic effect between the Co–carbonaceous material and the yolk–shell structure, which optimizes the impedance matching. The polarization loss, conductivity loss, magnetic loss, and multiple scattering mainly contribute to the excellent EMW-absorption ability of the materials. The proposed method for regulating the structure and morphology of Co@N/C can efficiently construct high-performance EMW absorbers. [Display omitted] • Yolk-Shell structure nanocomposite with excellent electromagnetic wave absorption properties was synthesized. • An excellent reflection loss (RL) of −67.68 dB at 15.88 GHz with an ultra-thin thickness (1.7 mm). • Effective absorption bandwidth (<−10 dB) up to 5.3 GHz under a single thickness (1.9 mm). [ABSTRACT FROM AUTHOR]

Organic acids play important roles in the atmosphere by contributing to formation of secondary organic aerosol (SOA), cloud condensation nuclei (CCN), and rainwater acidity. Vehicle emissions can be an important source of organic acids in urban environments. In this study, we carried out chassis dynamometer tests to measure C1–C5 carboxylic acids, hydrogen cyanide (HCN), and isocyanic acid (HNCO) from gasoline, diesel, and liquefied petroleum gas (LPG) vehicles using an iodide-adduct time-of-flight chemical ionization mass spectrometer (I− ToF-CIMS). We present fuel-based and mileage-based emission factors base on 31 vehicles under different stages of emission standards. Our measurements show that emission factors of carboxylic acids from diesel vehicles are much higher than those from gasoline vehicles. The determined emission factors of formic acid from diesel vehicles (130 ± 134 mg/kg fuel) are nearly 800 times higher than those from gasoline vehicles (0.16 ± 0.18 mg/kg fuel), which suggests that fuel type is a key metrics affecting emission factors of carboxylic acids from motor vehicles. We quantified the emission factors of toxic species HCN (gasoline: 10.4 ± 17.5 mg/kg fuel , diesel: 12.5 ± 7.49 mg/kg fuel) and HNCO (gasoline: 0.09 ± 0.25 mg/kg fuel , diesel: 2.26 ± 8.94 mg/kg fuel). Although the main source of organic acids is likely to be related to secondary production mechanisms on global scales according to previous research, our results highlight that primary emissions from vehicles may contribute significantly to local and finer regional scales. Emission factors of organic acids obtained in this study can be used to constrain the budget of organic acids in urban environments. • Fuel types and emission standard stages are key metrics affecting emission factors of carboxylic acids, HCN and HNCO. • Emission factors of carboxylic acids from diesel vehicles are much higher than those from gasoline vehicles. • Carboxylic acids emitted by vehicles are mainly contributed by diesel vehicles, while HCN mainly by gasoline vehicles. [ABSTRACT FROM AUTHOR]

We aimed to explore the online signature modality for characterizing early-stage Alzheimer's disease (AD). A few studies have explored this modality, whereas many on online handwriting have been published. We focused on the analysis of raw temporal functions acquired by the digitizer on signatures produced during a simulated check-filling task. Sample entropy was exploited to measure the information content in raw time sequences. We show that signatures of early-stage AD patients have lower information content than those of healthy persons, especially in the time sequences of pen pressure and pen altitude angle with respect to the tablet. The combination of entropy values on two signatures for each person was classified with two linear classifiers often used in the literature: support vector machine and linear discriminant analysis. The improvements in sensitivity and specificity were significant with respect to the a priori group probabilities in our population of AD patients and healthy subjects. We show that altitude angle, when combined with pen pressure, conveys crucial information on the wrist-hand-finger system during signature production for pathology detection. [ABSTRACT FROM AUTHOR]

Spermidine, a natural polyamine, has been proven antioxidant function, but its pathway and mechanism of action remain unclear. Based on the oxidative stress model by 3-nitropropionic acid (3-NPA), the study explored the pathways by spermidine to rescue oxidative stress via autophagic process in goose granulosa cells by RNA-seq and RNA interference. In transcriptional regulation, in addition to KEGG pathways related to cell proliferation and differentiation, lots of KEGG pathways associated with inflammation, metabolism, and signaling were also significantly enriched in 3-NPA vs. 3-NPA + spermidine treatments. Six key genes (JUN , CD44 , KITLG , RND2 , BMP4 and KALRN) involved in spermidine-mediated anti-oxidative stress were screened. Furthermore, the experimental results showed that spermidine (80 μmol/L) significantly increased autophagic gene expression in goose granulosa cells, while EP300 -siRNA or MAP1S -siRNA also significantly increased autophagic process. The autophagic gene expressions were no difference between EP300 -siRNA and EP300 -siRNA + spermidine treatments, although spermidine significantly increased autophagic process of granulosa cells compared to MAP1S -siRNA alone. In addition, inhibition of mTOR pathway significantly increased autophagic gene expression, which was further enhanced by spermidine in combined with mTOR inhibitor. These results suggest that spermidine can alleviate oxidative stress by inducing autophagy regulated by EP300, MAP1S and mTOR as well as regulating other independent gene expressions in goose granulosa cells. • Spermidine improves oxidative stress in goose GCs by regulating autophagy and other independent gene expressions. • Transcriptomic techniques confirmed the target genes related to spermidine anti-oxidative stress by spermidine. • The autophagy pathway involved in anti-oxidative stress by spermidine was validated by gene interference analyses. [ABSTRACT FROM AUTHOR]

Gas insulated metal enclosed switchgear (GIS) has been widely used in the world because of its compact structure and adaption to the environment. However, due to frequent operation and other reasons, GIS disconnector is prone to mechanical failure with poor contact, leading to abnormal vibration signals. In this paper, a GIS disconnector contact fault simulation platform is built to collect vibration signals in three states: normal contact, moderate poor contact and severe poor contact of disconnector contact. The Ensemble Empirical Mode Decomposition (EEMD) method is used to decompose the vibration signals, and the IMF decomposition signals are screened by Kurtosis criterion (a numerical statistic method). Finally, the vibration signal features of GIS under different conditions are obtained by reconstructing the screening signals. The results indicate that, under the normal contact, the frequency of GIS vibration signal mainly presents the distribution of 100 Hz and its integer multiple frequency component, when there is a contact defect, the high frequency component in the vibration signal spectrum increases significantly, and the tripling frequency component is present, and the amplitude of component will increase with the severity of the fault. Therefore, this study provides a theoretical reference for on‐line monitoring of GIS disconnecting switch contact fault. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

To investigate the relationship between polyamine metabolism and reproductive hormones in ovarian follicles of Sichuan white geese, follicle polyamine content and reproductive hormone levels and gene expressions related to polyamine metabolism, steroidogenesis and steroid hormone receptors were detected by HPLC, ELISA and RT-qPCR. The results showed that the overall trend of spermidine and spermine levels increased first and then decreased as increasing follicle size, with the highest level in F3 and F5 follicles (P < 0.05). Putrescine and 17β-estradiol (E2) levels in hierarchical follicles were significantly lower than those in prehierarchical follicles (P < 0.05). Progesterone (P4) first increased and then decreased, with the highest level in the F5 follicle (P < 0.05). The expression levels of estrogen receptor 1 (ER1) showed an overall increase as increasing follicle size (except in F3 follicles), while estrogen receptor 2 (ER2) in hierarchical follicles was significantly lower than that in the prehierarchical follicles (P < 0.05). In addition, the overall expression level of progesterone receptor (PR) decreased, with no significant differences among F1, F2 and F3 follicles (P > 0.05). Yolk putrescine contents were positively correlated with yolk E2 concentrations and PR expression levels (P < 0.05), A significant positive correlation of spermidine levels with yolk P4 concentrations and PR expressions was also observed, as well as the spermine levels with yolk P4 concentrations (P < 0.05). In summary, polyamines were involved in the regulation of follicular development in geese, and this regulation played a role in affecting steroidogenesis and the expression of genes related to hormone receptors. • Polyamine affects the steroidogenesis. • Polyamine contents show a specific change during goose follicular development. • Polyamine affects the expression of genes related to reproductive hormones. [ABSTRACT FROM AUTHOR]

Daytime HONO photolysis is an important source of atmospheric hydroxyl radicals (OH). Knowledge of HONO formation chemistry under typical haze conditions, however, is still limited. In the Multiphase chemistry experiment in Fogs and Aerosols in the North China Plain in 2018, we investigated the wintertime HONO formation and its atmospheric implications at a rural site Gucheng. Three different episodes based on atmospheric aerosol loading levels were classified: clean periods (CPs), moderately polluted periods (MPPs) and severely polluted periods (SPPs). Correlation analysis revealed that HONO formation via heterogeneous conversion of N O 2 was more efficient on aerosol surfaces than on ground, highlighting the important role of aerosols in promoting HONO formation. Daytime HONO budget analysis indicated a large missing source (with an average production rate of 0.66 ± 0.26, 0.97 ± 0.47 and 1.45 ± 0.55 ppbV/hr for CPs, MPPs and SPPs, respectively), which strongly correlated with photo-enhanced reactions (N O 2 heterogeneous reaction and particulate nitrate photolysis). Average OH formation derived from HONO photolysis reached up to (0.92 ± 0.71), (1.75 ± 1.26) and (1.82 ± 1.47) ppbV/hr in CPs, MPPs and SPPs respectively, much higher than that from O 3 photolysis (i.e., (0.004 ± 0.004), (0.006 ± 0.007) and (0.0035 ± 0.0034) ppbV/hr). Such high OH production rates could markedly regulate the atmospheric oxidation capacity and hence promote the formation of secondary aerosols and pollutants. [ABSTRACT FROM AUTHOR]

Spermidine is a naturally occurring polyamine compound that has many biological functions, such as inducing autophagy and anti-inflammatory and anti-aging effects. Spermidine can affect follicular development and thus protect ovarian function. In this study, ICR mice were fed exogenous spermidine drinking water for three months to explore the regulation of ovarian function by spermidine. The results showed that the number of atretic follicles in the ovaries of spermidine-treated mice was significantly lower than that in the control group. Antioxidant enzyme activities (SOD, CAT, T-AOC) significantly increased, and MDA levels significantly decreased. The expression of autophagy protein (Beclin 1 and microtubule-associated protein 1 light chain 3 LC3 II/I) significantly increased, and the expression of the polyubiquitin-binding protein p62/SQSTM 1 significantly decreased. Moreover, we found 424 differentially expressed proteins (DEPs) were upregulated, and 257 were downregulated using proteomic sequencing. Gene Ontology and KEGG analyses showed that these DEPs were mainly involved in lipid metabolism, oxidative metabolism and hormone production pathways. In conclusion, spermidine protects ovarian function by reducing the number of atresia follicles and regulating the level of autophagy protein, antioxidant enzyme activity, and polyamine metabolism in mice. [ABSTRACT FROM AUTHOR]

• A novel Nd 2 Zr 2 O 7 microbelts. • Electrospinning technology. • A pyrochlore-type crystal structure. • A feasible formation mechanism. Nd 2 Zr 2 O 7 microbelts were successfully prepared by simple electrospinning paired with calcination. The composition, microstructure, and structure of the as-prepared Nd 2 Zr 2 O 7 microbelts were systematically characterized through a combination of characterisations, such as XRD, SEM, TEM, FT-IR, and TG-DSC techniques. Results indicated that the as-prepared Nd 2 Zr 2 O 7 microbelts had a pyrochlore-type crystal structure and uniform size with about 10 μm thickness. Moreover, a feasible formation mechanism of the Nd 2 Zr 2 O 7 microbelts was discussed. The present procedure can be expanded to develop other rare-earth zirconate materials with belt structure. [ABSTRACT FROM AUTHOR]

Based on the established LIDAR chain along the 120°E meridian in China, the gravity wave (GW) activity between 80 and 105 km and the seasonal behavior of temporal and spatial spectra at Beijing, Hefei and Hainan were studied with three years of continued observations. The averaged GW-induced atmospheric density perturbations are near 6%, which in summer are obviously larger than in winter. The semiannual maxima occur near the solstice and the minimum emerges around the equinox at different latitudes. Besides, as a disparity, the density perturbation of GW is still active considerably in winter at low latitude at Hainan. The spectra of vertical wave number Fa(m) and observed frequency Fa(ω) show power law shapes, of which the average is near −3 and −1.7, respectively, and both spectra with special values all exhibit similar seasonal behavior as the atmospheric density perturbations shows. This behavior is explained by multiple effects possibly originating from Tibet plateau (TP) and the main GW source in China was roughly calculated by the LIDAR observation method for the first time located at the TP boundary. [ABSTRACT FROM AUTHOR]

We report a world record of lidar profiling of metallic Ca+ ions up to 300 km in the midlatitude nighttime ionosphere during geomagnetic quiet time. Ca+ measurements (∼80–300 km) were made over Beijing (40.42°N, 116.02°E) with an Optical‐Parametric‐Oscillator‐based lidar from March 2020 through June 2021. Main Ca+ layers (80–100 km) persist through all nights, and high‐density sporadic Ca+ layers (∼100–120 km) frequently occur in summer. Thermosphere‐ionosphere Ca+ (TICa+) layers (∼110–300 km) are likely formed via Ca+ uplifting from these sporadic layers. The lidar observations capture the complete evolution of TICa+ layers from onset to ending, revealing intriguing features. Concurrent ionosonde measurements show strong sporadic E layers developed before TICa+ and spread F onset. Neutral winds can partially account for observed vertical transport but enhanced electric fields are required to explain the results. Such lidar observations promise new insights into E‐ and F‐region coupling and plasma inhomogeneities. Plain Language Summary: Inhomogeneities (also called irregularities) in the ionospheric plasma distribution can significantly degrade satellite communications and negatively impact Global Positioning System‐based navigation systems that rely on the trans‐ionospheric radio‐wave propagation. Understanding the formation mechanisms of, thus predicting, ionospheric inhomogeneities is still a huge challenge in space weather research. Long‐lived meteoric metal ions (≫ $\gg $1 day above 100 km altitude) converge to form dense ion layers, causing plasma irregularities in the ionosphere. Therefore, it is imperative to observe and understand the transport and formation of metallic ion layers. However, it is technically challenging to detect specific ion species, especially tracing ion transport over large vertical ranges and time durations. Numerous instruments detect electron density but cannot distinguish ion species. Rocket‐borne mass spectrometers can distinguish ion species but provide only snapshots. Lidars provide a powerful tool to profile and trace metallic species over extended periods by exciting specific resonance fluorescence. The only metal ions detectable by ground‐based lidars are Ca+, and previous lidar measurements reached ∼180 km. Our Ca+ lidar upgraded with narrowband lasers has achieved high detection sensitivity, enabling the Ca+ profiling up to 300 km. Such lidar measurements of dynamical Ca+ layers open a new window to study plasma irregularities. Key Points: First lidar profiling of Ca+ ions from ∼80 to 300 km was made over Beijing in the nighttime ionosphere during geomagnetic quiet timeThermosphere‐ionosphere Ca+ layers (∼10 s cm−3) are likely formed by uplifting ions from sporadic Ca+ at ∼110 km & show complex structuresSpread F occurs concurrently with Thermosphere‐ionosphere Ca+ & strong sporadic E layers occur before the onset of TICa+ and spread F, suggesting E‐ and F‐region coupling [ABSTRACT FROM AUTHOR]

During the total solar eclipse on July 22, 2009 in Wuhan, the joint observation test of Na layer and ionosphere was conducted by using the daytime observation atmospheric lidar and the GPS ionosphere detector. The results show that the full width at half maximum (FWHM) of Na layer density slightly narrowed during the total solar eclipse and broadened after the eclipse, while the height of Na peak slightly decreased in the eclipse and increased after the eclipse. These implying that Na layer changes reflect the rapid process of sunrise and sunset. The ionosphere total electron content (TEC) and the sky background light noise also presented an obvious fluctuation characteristic with the changes of solar irradiation during the process of total solar eclipse. The difference lies in that the changes of FWHM of Na layer atoms are much slower than that of ionosphere, the reason for this might be that the Na layer, after being disturbed by the total solar eclipse, will generate a series of complicated photochemical reactions and momentum transport processes, and then recombine the Na atoms. The Na atoms to be detected by the lidar need a lag process, which rightly conforms to the theoretical simulated results. [ABSTRACT FROM AUTHOR]

The mechanical properties of the tissue engineering scaffold are important as they are tightly related the regeneration of structural tissue. The application of poly( l-lactic acid) (PLLA) nanofiber scaffolds in tissue engineering has been hindered by their insufficient mechanical properties. In the study, halloysite nanotubes (HNTs) were used to reinforce the mechanical properties of PLLA-based nanofibers. 4 wt% HNT/PLLA nanofiber membranes possess the best mechanical performance, which represents 61 % increase in tensile strength, 100 % improvement of Young's modulus, 49 % augment of elongation to break, as well as 181 % elevation in energy to break compared with neat PLLA samples. The satisfactory enhancement effect of HNTs can be attributed to the effective dispersion and incorporation of HNTs in PLLA matrix, which have been confirmed by the analysis of SEM, TEM, and FTIR. The addition of HNTs also improves the degree of crystallization and thermal stability of PLLA-based nanofibers. HNT-incorporated PLLA nanofiber membranes possess higher protein adsorption from fetal bovine serum than the neat PLLA specimen. Therefore, the introduction of HNTs can effectively enhance the mechanical properties of PLLA nanofiber scaffolds. HNT/PLLA nanofiber scaffolds possess potential application in skin tissue engineering. [ABSTRACT FROM AUTHOR]

[Display omitted] • An efficient and accurate method for polyamine detection was established. • This method can be used to detect polyamines in poultry tissues. • Uncovering the distribution pattern of polyamines in poultry tissues. • To study the effect of exogenous spermine on polyamine deposition in geese. Polyamines are widely present in animal cells and perform important physiological and biochemical functions. Moderate intake of polyamines contributes to good health. Poultry is one of the common sources of polyamines in daily life. However, different tissues from poultry contain different amounts of polyamine. In this study, an efficient and accurate method for the determination of polyamines was developed by high-performance liquid chromatography (HPLC) with precolumn benzoyl chloride derivatization. The linearity of the polyamines was good between 10–400 nmol/mL, with the limit of detection (LOD, S/N = 3) and limits of quantification (LOQ, S/N = 10) were 0.37 and 1.23 nmol/mL. The recoveries of the method ranged from 94.73 % to 106.58 % with high accuracy (RSD < 7 %) and no significant matrix effects or interferences. The RSD of intra-day, inter-day and inter-batch repeatability in the range of 0.07–1.57 %, 0.08–1.03 % and 1.46–4.57 %. The method was successfully used to detect polyamines in poultry tissue, with putrescine, spermidine and spermine levels ranging from 3.24 to 29.85 mg/kg, 0.46 to 164.11 mg/kg and 63.39 to 489.57 mg/kg, respectively. Polyamine levels were higher in the spleen, thymus and bursa of fabricius and lower in the heart and muscle. Furthermore, the method was employed to study the effect of exogenous spermine on polyamine deposition in different tissues of geese. In summary, the method is suitable for the detection of polyamine in animal tissues. [ABSTRACT FROM AUTHOR]

• A neural-network-based framework is proposed for performance prediction and inverse design of a porous auxetic metamaterial. • The real-time prediction towards the auxeticity and stiffness can improve the inverse design. • The framework can be extended to structural material design with complex characteristics. Auxetic metamaterials are widely applied in energy-absorbing systems and soft robots due to their superior mechanical properties. The properties of auxetic metamaterials are determined by their architectures, which means it is feasible to obtain metamaterials with target performance through structural design. This paper proposes a framework with neural networks to generate a nearly real-time prediction of the auxeticity and stiffness simultaneously of porous materials. Trained neural networks accurately provide computationally inexpensive predictions on response histories. Based on the prediction database given by the neural network, the parametric analysis can be conducted to provide the mutual influence and trend relationship of auxeticity and stiffness of the porous metamaterial. In addition, inverse design can also be conducted for seeking optimal architecture in terms of the auxeticity and stiffness quickly and accurately. With the method, the target nonlinear properties can be accurately and rapidly designed for porous metamaterials. The relative error of neural network predictions is less than 1.5% compared with experimental tests, and less than 8.0% compared with the numerical simulations obtained by the finite element method. The proposed framework can be extended to more structural materials to provide design guideline. [Display omitted] [ABSTRACT FROM AUTHOR]

As is known to all, environmental barrier coating requires high bonding strength and low thermal conductivity to extend the service life of ceramic matrix composite (CMC) components. In this work, a novel nanostructured Lu 2 Si 2 O 7 /Lu 2 SiO 5 environmental barrier coating was deposited successfully using as-synthetized Lu 2 Si 2 O 7 feedstocks and Lu 2 SiO 5 feedstocks. Meanwhile, the microstructure, bonding strength and thermal conductivity of Lu 2 Si 2 O 7 /Lu 2 SiO 5 coating were analysed systematically. Results indicate that the nanostructured Lu 2 Si 2 O 7 /Lu 2 SiO 5 environmental barrier coating processes a bi-model microstructure. The Lu 2 Si 2 O 7 /Lu 2 SiO 5 coating is relatively dense and the Lu 2 Si 2 O 7 layer and Lu 2 SiO 5 layer achieve the mechanical interlocking. The bonding strength of Lu 2 Si 2 O 7 /Lu 2 SiO 5 coating is 14.9 MPa. In addition, the thermal conductivity of Lu 2 Si 2 O 7 /Lu 2 SiO 5 coating is 0.59 W·m−1·K−1–1.24 W·m−1·K−1 from 25 °C to 1200 °C, which is visibly lower than that of Lu 2 SiO 5 coating. • A novel nanostructured Lu 2 Si 2 O 7 /Lu 2 SiO 5 environmental barrier coating was fabricated successfully. • The bonding strength of nanostructured Lu 2 Si 2 O 7 /Lu 2 SiO 5 coating is 14.9 MPa. • The thermal conductivity of Lu 2 Si 2 O 7 /Lu 2 SiO 5 coating is 0.59 W·m−1·K−1–1.24 W·m−1·K−1, which is lower than that of Lu 2 SiO 5 coating. [ABSTRACT FROM AUTHOR]

Owing to the unique optophysical properties of nanomaterials and their self-calibration characteristics, nanomaterial-based (e.g., polymer dots (Pdots) quantum dots (QDs), silicon nanorods (SiNRs), and gold nanoparticle (AuNPs), etc.) ratiometric fluorescent sensors play an essential role in numerous biosensing and cell imaging applications. The dual-emission ratiometric fluorescence technique has the function of effective internal referencing, thereby avoiding the influence of various analyte-independent confounding factors. The sensitivity and precision of the detection can therefore be greatly improved. In this review, the recent progress in nanomaterial-based dual-emission ratiometric fluorescent biosensors is systematically summarized. First, we introduce two general design approaches for dual-emission ratiometric fluorescent sensors, involving ratiometric fluorescence with changes of one response signal and two reversible signals. Then, some recent typical examples of nanomaterial-based dual-emission ratiometric fluorescent biosensors are illustrated in detail. Finally, probable challenges and future outlooks for dual-emission ratiometric fluorescent nanosensors for biosensing and cell imaging are rationally discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • It proposed a detection method for the structural and quantitative analysis of GABA. • The limit of detection for GABA could reach up to 0.428% based on its THz spectrum. • The calculated results were in good agreement with their experimental results. • The vibrational motions of each THz and Raman peaks were quantitatively decomposed. γ-aminobutyric (GABA) is the most important inhibitory neurotransmitier in vertebrate central nervous systems. The content level of GABA is related to the different degree of malignancy gliomas. Thus, it can be considered a promising glioma biomarker. In this paper, the spectroscopic properties of GABA have been characterized by combining the THz spectroscopy with low-wavenumber Raman spectroscopy. The experimental results showed that, GABA exhibited three absorption peaks and three refractive index peaks in the range of 0.6–2.1 THz. The limit of detection can reach up to 0.428 % based on the absorption coefficient at the peak of 2.04 THz. Moreover, the low-wavenumber Raman spectrum of GABA showed seven characteristic peaks at 41.0, 50.8, 58.8, 77.2, 98.8, 115.6, 141.2 cm−1 in 0–150 cm−1 region. Moreover, the THz and low-wavenumber theoretical spectra of GABA were simulated with solid-state density function theory, respectively. The calculated results were in good agreement with the experimental observations. On the basis of calculated result, the vibrational motions of each THz and Raman characteristic modes were quantitatively decomposed by analytical mode-decoupling method, where the contribution percentages of external translation, external librations and intramolecular vibration of each vibration modes were analyzed Furthermore, the low-frequency characteristics of GABA was analyzed by combining the THz and low-wavenumber Raman spectroscopy. It is beneficial for the structural information analysis and quantitative identification of biomarker GABA in early stage diagnosis of glioma. [ABSTRACT FROM AUTHOR]

[Display omitted] • It provides Raman characteristics of the two specific brain tissues after bTBIs. • Four algorithms are performed to classify different bTBIs at different time points. • The highest accuracy is up to 95.3% for diagnosis of bTBIs at different time points. • It realizes diagnosis of bTBIs by combining Raman spectroscopy with machine learning. Blast-induced traumatic brain injury (bTBI) is a kind of nervous system disease, which results in a major health and economic problem to society. However, the rapid and label-free detection method with high sensitivity is still in great demand for the diagnosis of bTBI, especially for mild bTBI. In this paper, we report a new strategy for bTBI diagnosis through hippocampus and hypothalamus tissues based on Raman spectroscopy. The spectral characteristics of hippocampus and hypothalamus tissues of experimental bTBI in rats have been investigated for mild and moderate degrees at 3 h, 6 h, 24 h, 48 h, 72 h after blast exposure. The results show that the Raman spectra of mild and moderate bTBIs in 300–1700 cm−1 and 2800–3000 cm−1 regions exhibit significant differences at different time points compared with the control group. The main reason is the content change of proteins and lipids in hippocampus and hypothalamus tissues after bTBI. Moreover, four machine learning algorithms are used to automatically identify mild and moderate bTBIs at different time points (a total of 11 groups). The highest diagnostic accuracies are up to 95.3% and 88.5% based on Raman spectra of hippocampus and hypothalamus tissue, respectively. In addition, the classification performance of linear discriminant analysis classifier has been improved after data fusion. It is suggested that there has great potential as an alternative method for high-sensitive, rapid, label-free, economical diagnosis of bTBI. [ABSTRACT FROM AUTHOR]

Oxidative stress is considered to be one of the culprits of ovarian dysfunction. Spermidine (SPD) is a natural aliphatic polyamine that is widely present in living organisms and has been shown to exert preventive effects on various ageing-related diseases. This study seeks to investigate the potential preventive and protective effects of SPD on ovarian oxidative damage. Ovarian oxidative stress model in C57BL/6 mice was established by 3-nitropropionic acid. Female mice were administrated 10 mg/kg or 15 mg/kg SPD. The estrous cycle, serum hormone levels and mating test were measured to evaluate ovarian function. Follicle counts and AMH levels to assess ovarian reserve. Masson's trichrome to assess ovarian fibrosis. TUNEL analysis to evaluate follicular granulosa cells (GCs) apoptosis. Oxidative stress and autophagy indicators (Nrf2, HO-1, GPX4, LC3B, P62) were measured in vivo and in vitro. RNA-sequencing was performed on SPD-treated GC to study the effects of SPD on Akt and FHC/ACSL4 signaling. SPD supplementation improved ovarian endocrine function and reproductive capacity in oxidative stress mice. SPD regularized the estrous cycle and alleviated oxidative stress. Furthermore, SPD increased the ovarian reserve, reducing GC apoptosis by activating the Nrf2/HO-1/GPX4 pathway. RNA-sequencing showed that SPD induced 230 genes changes in porcine GC, which were mainly involved in oocyte meiosis, arginine biosynthesis and glutathione metabolism pathways. SPD attenuated H 2 O 2 -induced ferroptosis by regulating Akt/FHC/ACSL4 signaling. SPD alleviates oxidative stress and ferroptosis by regulating the Nrf2/HO-1/GPX4 and Akt/FHC/ACSL4 pathway, which may be a novel potential strategy to protect ovarian oxidative damage. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Video-assisted thoracoscopic surgery (VATS) is a new area of exploration and evolution in thoracic minimal invasive surgery. The uniportal VATS approach has become popular during lung resection for small nodules and ground glass lesions. Our objective is to investigate the efficacy, availability and safety of uniportal VATS anatomical segmentectomy compared with conventional VATS in patients for lung resection. Methods: Surgical patients of perioperative period who admitted and underwent uniportal, two-port and conventional three-port VATS segmentectomy were analyzed and compared retrospectively during the year 2017 to 2018. Results: During the research period, of 111 patients who had VATS anatomical segmentectomy, 38 underwent uniportal, 43 underwent two-port, and 30 underwent three-port VATS. Four patients underwent conversion to thoracotomy. There were no postoperative mortalities, and there were no significant differences among the three groups in surgical outcomes, including operative time, blood loss, conversions to thoracotomy, drainage time and volume, lymph node dissection, postoperative complications and hospital stay. The pain scores of visual analog scale (VAS) significantly decreased in uniportal group when operation is finished (P < 0.05). Conclusion: This study demonstrates that uniportal VATS anatomical segmentectomy is a quite safe surgical technology, as well as feasible, which can cause reduced postoperative pain and less surgical trauma compared to conventional VATS. More experiences and observations of large samples are on the way. [ABSTRACT FROM AUTHOR]

In computational ghost imaging, a spatial light modulator (SLM) can be used to modulate the light field. The relative locations and the number of light point pixels on an SLM affect the imaging quality. Usually, SLMs are two-dimensional arrays which are drawn uniformly or are randomly sparse. However, the patterns formed by a uniform array are periodic when the number of light point pixels is small, and the images formed by a random sparse array suffer from large background noise. In this paper, we introduce a coprime array based on the Eisenstein integer to optimize the light point pixel arrangement. A coprime array is widely used as a microwave radar receiving array, but less implemented in optics. This is the first time that a coprime array based on Eisenstein integer has been introduced in computational ghost imaging. A coprime array with this structure enhances the imaging quality when limited measurements are recorded, and it reduces background noise and avoids periodicity. All results are verified by numerical simulation. [ABSTRACT FROM AUTHOR]

When short current is interrupted in three-phase vacuum interrupter in switchgear, the “U”-type loop composed of external busbar, conductive rod, and vacuum interrupter, and its adjacent phases will generate external actual transverse magnetic field (EATMF) in the interrupter. The existence of EATMF will deflect the vacuum arc, which will affect the breaking performance of vacuum switch. In view of this situation, this article establishes two kinds of electrode system simulation models considering and not considering EATMF. The simulation results show that EATMF is not uniformly distributed in the interelectrode region, but is stronger in the contact cup edge area outside the “U”-type loop, weaker in the “U”-type loop, and mainly affects ${B} _{x}$. In different short-circuit cases, EATMF is also different due to the difference of phase distance and short current. In the case of three-phase short circuit, the magnetic field in the interelectrode region of the middle phase is most significantly affected by EATMF. EATMF is closely related to the structure size of vacuum switch. By changing the structure size of vacuum switch (e.g., phase spacing ${d}$ , conductive rod length ${h} _{1}$ , ${h} _{2}$), EATMF can be weakened to some extent. [ABSTRACT FROM AUTHOR]

Spermidine have been reported a role in antioxidative, antiaging, and antiinflammatory. Oxidative stress causes granulosa cell (GC) apoptosis, follicular atresia, and impairs poultry reproductive functions. Studies have found that autophagy is the protective mechanism against antioxidant stress and apoptosis in cells. However, the relationship between spermidine-induced autophagy, oxidative stress, and apoptosis in goose GCs remains unclear. In this study, we investigated the autophagy mechanism to mediate spermidine effects on the alleviation of oxidative stress and apoptosis in goose GCs. Follicular GCs were treated with spermidine combination with 3-Nitropropanoic acid (3-NPA), rapamycin (RAPA), and chloroquine (CQ) or with hydrogen peroxide, RAPA, and CQ. Spermidine upregulated the ratio of LC3-II/I, inhibited the accumulation of p62 protein, and induced autophagy. 3-NPA treatment significantly increased ROS production, MDA content, SOD activity, cleaved CASPASE-3 protein expression, and decreased BCL-2 protein expression in follicular GCs. Spermidine inhibited oxidative stress and apoptosis induced by 3-NPA. In addition, hydrogen peroxide-induced oxidative stress was inhibited by spermidine. However, the inhibitory effect of spermidine was eliminated under chloroquine. Our results demonstrated that spermidine relieved oxidative stress and apoptosis of GCs by inducing autophagy, indicating that spermidine has a great potential to maintain proteostasis and sustain granulosa cell viability in geese. [ABSTRACT FROM AUTHOR]

Background: Uniportal video-assisted thoracoscopic surgery (VATS) lobectomy has emerged as a promising and exciting approach for minimally invasive thoracic surgeries. However, nearly all reported uniportal VATS lobectomies are performed via an intercostal route, and chest wall trauma remains an issue. Here, we report the use of a novel uniportal VATS technique involving a subxiphoid route for pulmonary lobectomies. Methods: We retrospectively analyzed perioperative data for patients who underwent subxiphoid uniportal and traditional three-port VATS lobectomies from January 2016 to January 2017 at our hospital. Results: During the study period, 37 patients successively underwent subxiphoid uniportal VATS lobectomies, including three synchronous bilateral pulmonectomies; 68 patients underwent traditional three-port VATS. There were no surgical or 30-day postoperative mortalities, and no significant between-group differences were found in the number of retrieved lymph nodes, number of explored nodal stations, blood loss, drainage time, postoperative complications, or length of hospital stay. Operative time was longer in the subxiphoid uniportal VATS group than in the traditional three-port VATS group (P < 0.001). Visual analog scale (VAS) pain scores after surgery were significantly lower in the subxiphoid uniportal VATS group (P < 0.05). Conclusions: Subxiphoid uniportal VATS lobectomy is a safe and feasible surgical procedure associated with reduced surgical trauma and postoperative pain as well as improved cosmetic results compared with traditional VATS. Moreover, this procedure is better suited for patients receiving synchronous bilateral pulmonectomy. Further long-term follow-up analyses involving more patients are ongoing. Trial registry number: ClinicalTrials.gov NCT03051438. [ABSTRACT FROM AUTHOR]

Beijing Na–K lidar has been started running in 2010. This lidar has two laser beams: one dye laser emits a 589-nm laser beam for Na layer detection; the other dye laser emits a 770-nm laser beam for K layer detection. Under similar conditions, the echo signal of K layer is only about 2 orders of magnitude smaller than that of Na layer. This lidar has a sufficient Signal Noise Ratio (SNR). The structure and details of potassium layer can be effectively distinguished from a single original echo. Several examples of co-observation of density of Na and K layer showed some different results with previous studies. This lidar not only can supplement the lack of Na and K layer observation at this latitude region, but also provide evidence for the atmospheric sciences and space environment monitoring. [ABSTRACT FROM AUTHOR]

The link between hyperuricemia (HUA) and the risk of venous thromboembolism (VTE) has been well established. However, the mechanisms of thrombus generation and the effect of HUA on procoagulant activity (PCA) of erythrocytes remain unclear no matter in uremia or hyperuricemia. Here, phosphatidylserine (PS) exposure, microparticles (MPs) release, cytosolic Ca2+, TMEM16F expression, reactive oxygen species (ROS) and lipid peroxidation of erythrocyte were detected by flow cytometer. PCA was assessed by coagulation time, purified coagulation complex and fibrin production assays. The fibrin formation was observed by scanning electron microscopy (SEM). We found that PS exposure, MPs generation, TMEM16F expression and consequent PCA of erythrocyte in HUA patients significantly increased compared to those in healthy volunteers. Furthermore, high UA induced PS exposure, and MPs release of erythrocyte in concentration and time-dependent manners in vitro, which enhanced the PCA of erythrocyte and was inhibited by lactadherin, a PS inhibitor. Additionally, using SEM, we also observed compact fibrin clots with highly-branched networks and thin fibers supported by red blood cells (RBCs) and RBC-derived MPs (RMPs). Importantly, we demonstrated UA enhanced the production of ROS and lipid peroxidation and reduced the generation of glutathione (GSH) of erythrocyte, which enhanced TMEM16F activity and followed PS externalization and RMPs formation. Collectively, these results suggest that Ca2+-dependent TMEM16F activation may be responsible for UA-induced PS exposure and MPs release of RBC, which thereby contribute to the prothrombotic risk in HUA. [ABSTRACT FROM AUTHOR]

The increase of surface ozone during the Corona Virus Disease 2019 (COVID-19) lockdown in China has aroused great concern. In this study, we combine 1.5 years of measurements for ozone, volatile organic compounds (VOCs), and nitrogen oxide (NO X) at four sites to investigate the effect of COVID-19 lockdown on surface ozone in Dongguan, an industrial city in southern China. We show that the average concentrations of NO X and VOCs decreased by 70%–77% and 54%–68% during the lockdown compared to pre-lockdown, respectively. Based on the source apportionment of VOCs, the contribution of industrial solvent use reduced significantly (86%–94%) during the lockdown, and climbed back slowly along with the re-opening of the industry after lockdown. A slight increase in mean ozone concentration (3%–14%) was observed during the lockdown. The rise of ozone was the combined effect of substantial increase at night (58%–91%) and small reduction in the daytime (1%–17%). These conflicting observations in ozone response between day and night to emission change call for a more detailed approach to diagnostic ozone production response with precursor changes, rather than directly comparing absolute concentrations. We propose that the ratio of daily Ox (i.e. ozone + NO 2) enhancement to solar radiation can provide a diagnostic parameter for ozone production response during the lockdown period. Smaller ratio of daily O X (ozone + NO 2) enhancement to solar radiation during the lockdown were observed from the long-term measurements in Dongguan, suggesting significantly weakened photochemistry during the lockdown successfully reduces local ozone production. Our proposed approach can provide an evaluation of ozone production response to precursor changes from restrictions of social activities during COVID-19 epidemic and also other regional air quality abatement measures (e.g. public mega-events) around the globe. • Both VOCs and NO X significantly declined during the COVID lockdown in Dongguan China. • The largest reduction was observed from solvent use among various VOCs sources. • A new approach was proposed to evaluate the response of ozone production to precursor changes. [ABSTRACT FROM AUTHOR]

• The established shrouded blade model can take into account elastic support, shroud position change, stagger angle, and twist angle. • The dynamic model derived in this paper considers the coupling effect of impact and friction of adjacent shrouds and the inertia effects of passive blades. • The geometric structure of the shroud is considered by deducing a new mode shape function, and the construction of an elastic support beam with a variable section is realized. A new dynamic model of shrouded blades with elastic support and variable cross-section is derived based on the Timoshenko beam theory, in which factors to be considered include centrifugal stiffening, spin softening, Coriolis force, blade stagger angle, and twist angle. The proposed model (PM) is verified by comparing the dynamic frequency results of the finite element model (FEM) and the PM. An impact-friction model of shrouded blades is established which can take into account the inertia effects of two passive blades. By comparing the vibration response of the two models (PM and FEM), the established impact-friction model is verified. Finally, the influences of normal contact stiffness, blade root support stiffness, and shroud position on the vibration response of the system are analyzed. Meanwhile, bifurcation diagrams, time-domain waveforms, phase diagrams, Poincaré maps, and frequency spectrum are utilized to analyze the nonlinear vibration characteristics of shrouded blades. The results show that the impact and friction between adjacent shrouds will cause the complex nonlinear vibration of the blades. Under small initial gaps, hard nonlinear phenomena can be observed in the vibration response of the shrouded blade. While under small initial preloads, it shows an obvious soft nonlinear phenomenon. Furthermore, with the increase of normal contact stiffness and blade root support stiffness, the resonance peak of the blade-tip flexural displacement decreases. When the shroud is closer to the blade-tip of the blade, the vibration reduction effect of the shrouded blade is better. The active blade experiences the chaos, period-one motion due to the nonlinear behavior of the impact-friction coupling at the adjacent shroud contact interfaces. [ABSTRACT FROM AUTHOR]