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Abstract Nickel-catalyzed C–H bond functionalization reactions provide an impressive alternative to those with noble metal catalysts due to their unique reactivity and low cost. However, the regioselective C(sp2)–H borylation reaction of arenes accomplished by nickel catalyst remains limited. We herein disclose a silyl-directed ortho C(sp2)–H borylation of substituted arenes with a Ni(cod)2/PMe3/KHMDS catalyst system. Using readily available starting materials, this protocol provides easy access to ortho-borylated benzylic hydrosilanes bearing flexible substitution patterns. These products can serve as versatile building blocks for the synthesis of sila or sila/borine heterocycles under mild conditions. Control experiments and DFT calculations suggest that a catalytic amount of base prompts the formation of Ni(II)-Bpin-ate complex, likely related to the C(sp2)–H bond activation. This borylation reaction might follow an unusual Ni(II)/Ni(IV) catalytic cycle.

Abstract A novel quaternary copolymer of AA/AM/AOS/C16‐DMAAC was synthesized with acrylic acid (AA), acrylamide (AM), sodium α‐alkenyl‐sulfonate (AOS), and dimethyl‐hexadecyl‐allyl‐ammonium chloride (C16‐DMAAC), using ammonium persulfate and sodium bisulfate (NH4)2S2O8‐NaHSO3) as initiators. The structure of AA/AM/AOS/C16‐DMAAC was characterized using Fourier transform infrared spectroscopy and nuclear magnetic resonance hydrogen spectroscopy. It can be found that the thickening capacity, shearing resistance, temperature‐resistance, salt‐resistance, and emulsification properties of AA/AM/AOS/C16‐DMAAC were superior to those of most widely and cost‐effective partially hydrolyzed polyacrylamide (HPAM) solution at the same concentration. Specifically, the viscosity retention rate of AA/AM/AOS/C16‐DMAAC (3000 mg/L) solution was 86%, which was better than that of HPAM solution (52%) after 30 s of mechanical shearing at 28000 r/min. In addition, the enhanced oil recovery of AA/AM/AOS/C16‐DMAAC solution was 16% at 65 °C, which was about 1.5 times higher than that of HPAM solution (11%). Significantly, successful synthesis of zwitterionic quaternary copolymer emphasizes the importance of a systematic approach to designing appropriate copolymers for enhanced oil recovery. Highlights A novel zwitterionic quaternary copolymer of AA/AM/AOS/C16‐DMAAC was successfully synthesized. The performance on thickening capacity, shearing resistance, temperature‐resistance, salt‐resistance, and emulsification properties of AA/AM/AOS/C16‐DMAAC was superior to that of the most widely used partially hydrolyzed polyacrylamide (HPAM). The enhanced oil recovery of AA/AM/AOS/C16‐DMAAC (16%) was about 1.5 times higher than that of HPAM (11%).

Affected by the weakening of the low-pressure system caused by the northward movement of the typhoon "Doksuri", Hebei encountered an unprecedented severe torrential rain event (hereinafter referred to as "23.7" severe torrential rain) from 29 July to 2 August 2023, in which the accumulated rainfall in 52 hours is up to 1 003.4 mm at Liangjiazhuang station in Xingtai of southern Hebei. Using routine upper-air and surface weather observations, regional automatic weather station data, radar mosaic of reflectivity factor, ERA5 reanalysis data, and other relevant data, we conducted the analysis on the precipitation evolution characteristics, circulation patterns, environmental conditions, and mesoscale features of the "23.7" severe torrential rain. The results indicate that the "23.7" severe torrential rain is characterized by long duration, large accumulated rainfall and wide coverage. After landing and moving northward, Typhoon "Doksuri" is blocked by the high pressure barrier in northern North China at 500 hPa and stagnates. Total content of water vapor over most areas of Hebei reached more than twice the climate average state. All the factors, that low lifting condensation level, low free convection height, moderate convective instability energy, as well as the lasting convergence uplift provided by the stability and stagnation of inverted trough at 850 hPa, are the causes of maintaining precipitation echo for a long time in central Hebei and in the foothills of Taihang Mountains in southwestern Hebei. The southeasterly boundary layer jet moves northwards along with the typhoon inverted trough, and the jet core is located in central Hebei, with the wind speed exceeding 22 m·s-1 and terrain plays a significant role in the rainfall event. During the influence of boundary layer jet on southwestern Hebei, multiple convective cells with echo intensity of 30~40 dBz and centroid height lower than 6 km successively pass over the Liangjiazhuang station, causing a total of 24 hours of short-term severe rainfall at the station. After the boundary layer jet moving northwards, the rainfall overlapping, caused by the continued long-term maintenance of stratocumulus mixed cloud precipitation echo in the foothills of Taihang Mountains due to the interaction of easterly wind of about 8 m·s-1 and terrain, is the main reason of the 52-hour accumulated rainfall exceeding 1 000 mm at the Liangjiazhuang station.

To tackle issues like unbalanced currents in stator windings and power pulsations under unbalanced grid voltage conditions, this paper introduces a passive control strategy for the Brushless Doubly-Fed Reluctance Generator (BDFRG). The approach effectively suppresses current distortions in the stator windings, as well as second harmonic pulsations in the active and reactive power. First, the positive and negative sequence equations of the BDFRG are established using the symmetric component method. Then, passive feedback controllers are designed for both positive and negative sequences by using the Euler-Lagrange (EL) model and the passivity theory. Finally, the given values of the positive and negative currents of the power winding and control winding are calculated to obtain the passive feedback controllers for the BDFRG under unbalanced grid voltages. Simulations and hardware-in-the-loop (HIL) experiments are conducted to validate the correctness of the derived model and assess the effectiveness of the control strategy.

Abstract Purpose The purpose of this study was to investigate the clinical utility of three-dimension (3D) high-resolution inversion recovery (IR)-prepared fast spoiled gradient-recalled (SPGR) magnetic resonance imaging (MRI) in the diagnosis of cranial nerve meningeal carcinomatosis (MC). Methods A total of 114 patients with MC from January 2015 to March 2020 were enrolled and their MRIs were analyzed retrospectively. All patients underwent MRIs before being administered a contrast agent. Both a 2D conventional MRI sequence and a 3D IR-prepared fast SPGR high-resolution T1-weighted (BRAVO) scan sequence were measured after contrast agent administration. The characteristics of MC and the involved cranial nerves were then examined. Results Among the 114 MC patients, 81 (71.05%) had cranial nerve enhancement on contrast-enhanced 3D-BRAVO imaging, while only 41 (35.96%) had image enhancement on conventional MRI. The contrast-enhanced 3D-BRAVO displayed stronger image contrast enhancement of the cranial nerves than the conventional MRI (P

In this paper, a creative dung beetle optimization (CDBO) algorithm is proposed and applied to the offline parameter identification of permanent magnet synchronous motors. First, in order to uniformly initialize the population state and increase the population diversity, a strategy to improve the initialization of the dung beetle population using Singer chaotic mapping is proposed to improve the global search performance; second, in order to improve the local search performance and enhance the convergence accuracy of the algorithm, a new dung beetle position update strategy is designed to increase the spatial search range of the algorithm. Simulation results show that the proposed optimization algorithm can quickly and accurately identify parameters such as resistance, inductance, and magnetic chain of the PMSM, with significant improvements in convergence algebra, identification accuracy and stability.

Abstract Environment perception is one of the most vital function for autonomous robots while performing complex tasks in dynamic environment. In binocular stereo vision algorithm, the calculation of disparity image depends on matching algorithm, and the unmatched points form depth holes in the image. When encountering obstacles with less texture, such as blank walls, large area deep holes will often appear. Although the existing filtering algorithm can solve the problem of small area deep hole, it cannot be applied to large area deep hole. To solve this problem, a depth hole optimization algorithm is proposed, which detects large area depth holes from the image globally, fills the depth holes according to the disparity value distribution, and optimizes the weighted least squares filtering effect. The experimental results show that the average time of the algorithm is only 15 ms.

In order to improve wind power utilization efficiency and reduce wind power prediction errors, a combined prediction model of EMD-KPCA-BilSTM-ATT is proposed, which includes a data processing method combining empirical mode decomposition (EMD) and kernel principal component analysis (KPCA), and a prediction model combining bidirectional long short-term memory (BiLSTM) and an attention mechanism (ATT). Firstly, the influencing factors of wind power are analyzed. The quartile method is used to identify and eliminate the original abnormal data of wind power, and the linear interpolation method is used to replace the abnormal data. Secondly, EMD is used to decompose the preprocessed wind power data into Intrinsic Mode Function (IMF) components and residual components, revealing the changes in data signals at different time scales. Subsequently, KPCA is employed to screen the key components as the input of the BiLSTM-ATT prediction model. Finally, a prediction is made taking an actual wind farm in Anhui Province as an example, and the results show that the EMD-KPCAM-BiLSTM-ATT combined model has higher prediction accuracy compared to the comparative model.

A novel hyperbranched polymer with polyacrylamide side chains (HAPAM) was synthesized by aqueous solution polymerization using acrylic acid, acrylamide, 2-acrylamido-2-methyl-1-propanesulfonic acid, hydrophobic monomer of dimethyl octadecyl ammonium chloride, and the homemade skeleton monomer of modified-M2.0 as raw materials and (NH4)2S2O8-NaHSO3 as initiator. The molecular structure, functional groups, and surface morphology of HAPAM were characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance hydrogen spectroscopy, and scanning electron microscopy. It was found that the performance of HAPAM solution was higher than that of ordinary polyacrylamide solution in terms of thickening ability, shearing resistance, thermal endurance, salt-resistance, resistance-coefficient and residual-resistance-coefficient, ability to reduce interfacial tension between polymer solution and crude oil, and oil-displacement-efficiency. In particular, the enhanced oil recovery of the HAPAM solution was 13.03%, and the improvement of shearing resistance and immunity to chromatographic separation were simultaneously achieved by the HAPAM solution. These results indicate that the successful synthesis of the novel HAPAM opens a promising strategy for developing new high-performance oil-displacing polymers.

Objective To investigate whether there is a correlation between the differences in ABO blood group distribution in patients with pancreatic cancer, and to evaluate the relative risk. Methods Patients with pathological diagnosis or discharge diagnosis of pancreatic cancer who underwent ABO blood group typing in our hospital from January 2017 to October 2021 were selected, and the blood group distribution of patients and the correlation were analyzed. Results There was a statistically significant difference between the pancreatic cancer group and the control group (P

The coregistration of optical and synthetic aperture radar (SAR) imageries is the bottleneck in exploring the complementary information from the two multimodal datasets. The difficulties lie in not only the complex radiometric relationship between them, but also the distinct geometrical models of the optical and SAR imaging systems, which cause it nontrivial to explicitly depict the spatial relationship between the corresponding image regions when elevation fluctuations exist. This article aims to investigate the optical flow technique for the pixelwise dense registration of the high-resolution optical and SAR images, so as to get rid of the outlier removal and geometric mapping procedures, which have to be conducted in the classical image registration approaches that are based on sparse feature point matching. Herein, a deep optical flow framework is designed. First, a dilated feature concatenation method is proposed to enhance the discriminability of the pixelwise features for similarity measurement. An effective network training strategy is used, based on a smoothed flow loss, and also a training dataset that contains simulated elevation fluctuations. Second, we propose a self-supervised optical flow fine-tuning strategy. It incorporates the strength of the blockwise matching approach, which produces better matching precision, into the proposed pixelwise matching procedure. In this way, the accuracy of the optical-SAR dense registration is substantially improved. Extensive experiments conducted on the 1-m resolution optical-SAR image pairs of different land-cover types and distinct topographic conditions indicate that the proposed optical-SAR optical flow network -Ft framework is quite robust, and has the potential to perform the optical-SAR image dense registration in practical applications. The Python code of the proposed deep optical flow network will be made available.

The Virtual Synchronous Generator (VSG) emulates the characteristics of a synchronous generator to provide inertia and damping for renewable energy systems. In the case of using the NPC three-level converter structure, traditional control methods require complex dual-loop control and internal PI parameter tuning. Furthermore, although fixed-parameter VSG control can provide inertia and damping when a significant power load is switched in an islanded microgrid, it cannot guarantee frequency regulation performance. To address these issues, this paper proposes an NPC three-level VSG parameter adaptive finite control set model predictive control strategy. This method eliminates the need for dual-loop control and PI parameter tuning. By incorporating angular velocity deviation and its rate of change into adaptive adjustment, a Tracking-Differentiator (TD) is designed to calculate the rate of change of angular velocity. This approach avoids frequent fluctuation of adaptive parameters during load power switching and improves the frequency stability of the microgrid. The effectiveness of the proposed strategy is validated through simulation and experimental verification.

Abstract Analysing the steady‐state operation characteristic of the modular multilevel converter (MMC) in time domain poses challenges due to the presence of harmonic components in the arm current and capacitor voltage. While ignoring the influence of the harmonic currents and harmonic voltages would reduce the accuracy of the analysis results for MMC. This paper investigates the circular interaction among the electrical quantities and different order harmonic components in MMC. A new steady‐state model is developed and the general matrix equation is established to accurately describe the explicit analytical expressions for electrical variables in MMC without specific assumptions. Based on the steady‐state operation characteristic analysis, the resonance phenomenon and characteristic are identified for MMC. Finally, the feasibility and accuracy of the proposed method are verified by comparing its analytical results with simulation and experimental results.

Because of the special absorption peak, pulsed lasers at 1.7 μm have been rapidly developed in medical treatment, biological imaging and so on. Introducing the cylindrical vector beam (CVB) may further promote these special applications due to its unique intensity, phase and polarization characteristics. Herein, we have experimentally demonstrated the generation of wavelength-tunable pulsed CVBs at 1.7 μm based on a thulium-doped all-fiber laser. A bandpass filter with a wide bandwidth combined with nonlinear polarization rotation technology is used to obtain pulsed laser emission at 1.7 μm. By taking advantage of a home-made Lyot filter and mode selective coupler (MSC), pulsed CVBs can be obtained with a wavelength tuning range of 66 nm (1720–1786 nm). The development of wavelength-tunable pulsed CVBs at the 1.7 μm waveband has significant potential applications in deep bioimaging and laser processing.

Objective To compare the efficacy and safety of transfusion of suspended RBCs and washed RBCs in patients with positive direct Coombs testing results. Methods A retrospective analysis was conducted on 98 patients with positive direct Coombs testing results as 2+ or less in the First Affiliated Hospital of Chongqing Medical University from January 2015 to December 2020. Among them, 31 patients, from January 2015 to December 2016, were transfused with washed RBCs and set as the control group; the other 67 patients, from January 2017 to December 2020, transfused with suspended RBCs, were enrolled as the experimental group. The changes of main laboratory indexes and the incidence of transfusion adverse reactions before and after transfusion of 2 U and 4 U RBCs were compared between the two groups to evaluate the efficacy and safety of transfusion. Results After 2 U and 4 U transfusion, Hb increased by 12±4.967 (g/L) and 23.78±12.736 (g/L) in the control group, while 12.85±7.109 (g/L) and 22.68±9.832 (g/L) in the experimental group, All transfusions of the two groups were effective, and no significant differences in Hb, TBIL, IBIL and LDH were noticed by groups (P>0.05). No significant difference in the incidence of adverse reactions to blood transfusion between the 2 groups was observed (P>0.05). Conclusion The transfusion of suspended RBCs is safe and effective in patients with positive direct Coombs testing results as 2+ or less, and the transfusion of washed RBCs was unnecessary.

Heavy metal pollution in soils caused by mining has led to major environmental problems around the globe and seriously threatens the ecological environment. The assessment of heavy metal pollution and the local phytoremediation potential of contaminated sites is an important prerequisite for phytoremediation. Therefore, the purpose of this study was to understand the characteristics of heavy metal pollution around a copper-nickel mine tailings pond and screen local plant species that could be potentially suitable for phytoremediation. The results showed that Cd, Cu, Ni, and Cr in the soil around the tailings pond were at the heavy pollution level, Mn and Pb pollution was moderate, and Zn and As pollution was light; The positive matrix factorization (PMF) model results showed that the contributions made by industrial pollution to Cu and Ni were 62.5% and 66.5%, respectively, atmospheric sedimentation and agricultural pollution contributions to Cr and Cd were 44.6% and 42.8%, respectively, the traffic pollution contribution to Pb was 41.2%, and the contributions made by natural pollution sources to Mn, Zn, and As were 54.5%, 47.9%, and 40.0% respectively. The maximum accumulation values for Cu, Ni, Cr, Cd, and As in 10 plants were 53.77, 102.67, 91.10, 1.16 and 7.23 mg/kg, respectively, which exceeded the normal content of heavy metals in plants. Ammophila breviligulata Fernald had the highest comprehensive extraction coefficient (CEI) and comprehensive stability coefficient (CSI) at 0.81 and 0.83, respectively. These results indicate that the heavy metal pollution in the soil around the copper nickel mine tailings pond investigated in this study is serious and may affect the normal growth of plants. Ammophila breviligulata Fernald has a strong comprehensive remediation capacity and can be used as a remediation plant species for multiple metal compound pollution sites.

Abstract Focussing on the ineffective operating cycle and potential battery life degradation introduced by traditional energy converter‐based balancing techniques, a new distributed online active balancing scheme is proposed. In order to achieve a wider output voltage range, a new distributed converter is presented first, which can operate in boost or buck mode. Then, by regulating the discharge rate of each smart cell proportional to the deviation between its own state of charge (SOC) and the average SOC of all cells, an online linear SOC balancing scheme is presented. An experimental prototype consisting of eight smart cells is developed, experiments in constant resistance discharging mode and dynamic current discharging mode are carried out, and the results demonstrate the successful cell SOC balancing and DC bus adjustment capability of the proposed scheme.

Based on conventional meteorological observations, observational data from the regional automatic weather stations, NCEP reanalysis data with spatial resolution of 1°×1° and temporal resolution of 6 h, satellite images, Doppler weather radar and wind profiler data, as well as the retrieval results from BeijingVariational Doppler Radar Analysis System (VDRAS), we have conducted analysis of the precipitation characteristics, atmospheric circulation, mesoscale system evolution features and the causes of a regional warm-sector torrential rain event in the Beijing-Tianjin-Hebei region on 12 August 2020. The results show that the event occurs in the warm air mass below 500 hPa at the edge of the subtropical high, and the main influencing systems are the low-level jet and the warm shear line at the 850 hPa. The whole severe precipitation event presented clearly the phased characteristics; it can be divided into two stages corresponding to the two different rainstorm areas, i.e., the southern Hebei and the north part of the Beijing-Tianjin-Hebei region with different formation mechanisms. The severe precipitation in the first stage is caused by a meso-α-scale convective system (MαCS), which is triggered by the surface convergence line. Before the precipitation starts, the local water vapor and unstable energy is rich. When the surface convergence line triggers the release of unstable energy, a strong linear echo is formed. The severe precipitation is mainly caused by the continuous development of convective cells in the spiral echo corresponding to the surface cyclonic circulation. The severe precipitation in the second stage is generated by several β-scale cloud clusters, and the southerly low-level jet strengthened northward provides sufficient water vapor and better dynamic conditions for the occurrence of torrential rain. The low-level jet in the boundary layer and the mesoscale low vortex system are the crucial influence systems at the second stage of this event. The hourly extremely severe precipitation of 125.9 mm at a station in Xiongan New Area is caused jointly by the warm cloud precipitation at the tail of comma-shaped radar echo and the "train effect".

China’s military-civil fusion (MCF) policy has attracted global attention. Since 2010, China has constructed over 30 MCF national demonstration bases (MCFNDBs) to optimise local industrial structure and promote local economic development. However, the evaluation of the actual economic effects of these MCFNDBs has not reached a consensus. We use panel data for 285 cities from 2006–2017 to investigate the economic effect of MCFNDBs by difference-in-difference estimation. We find that constructing MCFNDBs are significantly beneficial to upgrading the urban industrial structure in less developed regions and provincial capital cities; however, it plays an insignificant role in the industrial structure rationalisation.

Background: The clinical application of autologous leukocyte-poor platelet-rich plasma (LP-PRP) in patients with recurrent implantation failure (RIF) is rare. This retrospective observational cohort study aimed to evaluate the efficacy of LP-PRP intrauterine infusion in patients with RIF. Methods: Patients with RIF undergoing frozen embryo transfer (FET) from January 2019 to December 2021 (n = 118) were enrolled, with those undergoing LP-PRP intrauterine infusion as the PRP group (n = 64), and those receiving no LP-PRP treatment as the control group (n = 54). The beta-human chorionic gonadotropin (β-hCG)-positive rate, clinical pregnancy rate (CPR), live birth rate (LBR), and miscarriage rate (MR) per ET cycle were compared. Results: The β-hCG-positive rate (57.8% vs. 38.9%, p = 0.041), CPR (45.3% vs. 24.5%, p = 0.022), and LBR per ET cycle (42.2% vs. 18.5%, p = 0.009) were higher in the PRP group than in the control group, and the three variables (62.5% vs. 41.2%, p = 0.040, 47.5% vs. 23.5%, p = 0.033, and 47.5% vs. 20.6%, p = 0.027) in the PRP group transferred with the blastocyst-stage embryos were also higher than those in the control group. The MR was similar in all groups. Conclusions: The LP-PRP treatment could improve the β-hCG-positive rate, CPR, and LBR in RIF patients undergoing FET cycles.

With the rise of mobile technology, the library reference service has dramatically changed. Targeting the new requirements, this paper aims to design a new library reference service system in Cordova-based hybrid frameworks, which caters to the web service embedded in two major mobile platforms, iOS and Android, as well as the PC platform. The new system adopts the WebSocket based technology to realize the function of independent online reference, which improves the quality of the normal digital reference service. The newly designed system also applies the ECS cloud server technology, thereby significantly slashing the hardware setup cost, extending the basic reference service, and improving its fitness-for-use and convenience, and optimizing the allocation of local resources.

Foamy viruses (FVs) are naturally found in many different animals and also in primates with the notable exception of humans, but zoonotic infections are common. In several species, two different envelope (env) gene sequence clades or genotypes exist. We constructed a simian FV (SFV) clone containing a reporter gene cassette. In this background, we compared the env genes of the SFVmmu-DPZ9524 (genotype 1) and of the SFVmmu_R289hybAGM (genotype 2) isolates. SFVmmu_R289hybAGM env-driven infection was largely resistant to neutralization by SFVmmu-DPZ9524-neutralizing sera. While SFVmmu_R289hybAGM env consistently effected higher infectivity and cell-cell fusion, we found no differences in the cell tropism conferred by either env across a range of different cells. Infection by both viruses was weakly and non-significantly enhanced by simultaneous knockout of interferon-induced transmembrane proteins (IFITMs) 1, 2, and 3 in A549 cells, irrespective of prior interferon stimulation. Infection was modestly reduced by recombinant overexpression of IFITM3, suggesting that the SFV entry step might be weakly restricted by IFITM3 under some conditions. Overall, our results suggest that the different env gene clades in macaque foamy viruses induce genotype-specific neutralizing antibodies without exhibiting overt differences in cell tropism, but individual env genes may differ significantly with regard to fitness.

Based on the Meteorological Information Comprehensive Analysis and Processing System Version 4 (MICAPS4),the R & D team of Hebei Meteorological Observatory independently designed and developed a set of disastrous weather case retrieval and training system. By the collation and preservation of historical disastrous weather cases and associated data,this system has not only realized the retrieval,analysis,training,collection,management of the weather cases and other functions,but also solved the accumulation and use of historical data. In additon,it has expanded historical data application function of the MICAPS system. This system can be used in such aspects as disastrous weather forecast and warning business,scientific research and forecaster training. It is highly portable and has a good prospect of popularization and application.

A regional thunderstorm gale weather event occurred in central and southern Hebei on 9 July 2017. It is a typical severe convective weather with the cold advection forcing in upper air. The convective cloud clusters successively affected the south area (I) and north area (II) of central and southern Hebei during this event. Based on the routine upper-air and surface observations, satellite cloud images, Doppler weather radar data, observations from regional automatic weather stations and NCEP reanalysis data with 1°×1° resolution, we have conducted an analysis of the environmental conditions and the evolution characteristics of the convective storm when this event occurred. The main results are as follow. (1) This event occurs under the background of the Mongolian cold vortex weather. The cold air at the rear of the cold vortex and the warm and wet air in the low-level jointly form an unstable stratification with the dry and cold air in high level and the warm and humid air in low level, in which vertical wind shear is strong in southern Hebei Province. The convection in area I is triggered by topographic uplift, and moves southeastwards under the action of northwest airflow in the high level. Nevertheless, the convection in area II is directly triggered by the cold front, and moves eastwards and northwards under the combined action of advection and propagation. (2) The convective systems causing the gale in area I include the squall line and the supercell associated with mesocyclone. The rear inflow jet below 1 km exceeds 31 m·s-1 in mature stage of the squall line. The surface gale appears at the front of the center of high wind speed, the front of the thunderstorm high and the vicinity of hourly positive pressure center. There are various types of convective systems causing the gale in area II, including supercell, block-shaped echo and squall line. The gale squall line appears between the rear side of gust front and the hourly positive pressure center. After the echo intensity of the squall line is decreased, the combined effect of the cold pool density flow, the downward momentum transportation and the allobaric wind can still cause surface gale. (3) The fact that high wind speed core exceeding 30 m·s-1 in the radar radial velocities at the low elevation angle corresponded to the hourly positive surface pressure change of over 5 hPa, and the descending velocity of 7-10 m·s-1 below 5 km followed by the strong northwest wind below 1 km in the wind profiler radar product can be used as a reference indicator for the 0-2 h nowcasting and warning of the thunderstorm gale above level 8 on the ground.

Due to the extremely complex composition of remote sensing scenes, REmote Sensing Image Scene Classification (RESISC) is still a challenging task. To further improve classification accuracy, this article introduces a deep-learning detector into RESISC and proposes to classify remote sensing images according to the detected class-specific signature objects. Inspired by the classification procedure of human vision system, we design a classification framework that utilizes class-specific signature objects of scene classes to guide scene classification. When performing image classification, the proposed framework first adopts a deep-learning classifier to create an initial judgment of the scene class for an image and then determines the scene class based on the class-specific signature objects detected from the image. The proposed method can compete with the state-of-the-art methods on three RESISC benchmark datasets, including NWPU-RESISC45, AID, and OPTIMAL-31.

Abstract Background Sepsis is the leading cause of death among critically ill patients, and no specific therapeutic agent is currently approved for the treatment of sepsis. Methods We assessed the effects of flagellin administration on survival, bacterial burden, and tissue injury after sepsis. In addition, we examined the effects on phagocytosis and bacterial killing in monocytes/macrophages. Results Therapeutic administration of flagellin increased bacterial clearance, decreased organ inflammation and injury, and reduced immune cell apoptosis after experimental sepsis, in a Toll-like receptor 5 (TLR5)–dependent manner. Macrophages, but not neutrophils, mediated the beneficial effects of flagellin on experimental sepsis, and flagellin induced macrophage polarization into M1 in septic mice. Flagellin treatment could directly enhance phagocytosis and bacterial killing of macrophages, but not neutrophils. Subsequent studies demonstrated that flagellin could promote phagosome formation and increase reactive oxygen species (ROS) levels in macrophages. Finally, we found that the expression of TLR5 was significantly elevated on the surface of circulating monocytes, but not neutrophils, from patients with sepsis. Higher expression levels of TLR5 on monocytes were associated with increased mortality, documented bacteremia, and higher Sequential Organ Failure Assessment scores of the septic patients. Moreover, flagellin treatment rescued the impaired phagocytosis and bacterial killing ability of monocytes/macrophages from patients who died of sepsis. Conclusions These novel findings not only established the potential value of application of flagellin as an immunoadjuvant in treating sepsis, but also provided new insights into targeted therapeutic strategy on the basis of monocyte TLR5 expression in septic patients.

In long-distance NDT based on ultrasonic guided waves with low-frequency excitation, the most commonly used industrial coupling agents are grease-like coupling agents. However, these agents show the poor performance in NDT, because they can cause more acoustic energy loss and lower acoustic transmissivity. In the study, to improve the acoustic transmission property of grease-like coupling agents, a new method was proposed to combine different metal ions like Li+, Na+ and Ca2+ with base grease, thus forming new grease-like coupling agents. By comparing with the ultrasonic transmitting property of the regular coupling agents, selects a premium ultrasonic grease-like coupling agent. In the experimental results, when low-frequency ultrasonic guided waves transmitted through the lithium-based coupling agent, except the slight delay of peak response time, pulse signals showed the higher energy transmission efficiency with the better pulse vibration waveforms in the iron medium than other oil-based coupling agents. The newly developed grease-like coupling agent can be easily prepared at a lower cost. Importantly, the new coupling agent can improve the energy transmission performance and greatly enhance the sensitivity of ultrasonic flaw detection. Keywords: Ultrasonic guided wave, NDT, Grease-like coupling agent, Chemical combination preparation

W-K-TiC alloys with different titanium carbide concentrations (0.05, 0.1, 0.25, 0.5, 1, 2) wt.% were fabricated through Mechanical Alloying and Spark Plasma Sintering. The effects of the addition of nano-scaled TiC particles on the relative density, Vickers micro-hardness, microstructure, crystal information, thermal shock resistance, and tensile strength were investigated. It is revealed that the doped TiC nano-particles located at the grain boundaries. The relative density and Vickers micro-hardness of W-K-TiC alloys was enhanced with TiC addition and the highest Vickers micro-hardness is 731.55. As the TiC addition increased from 0.05 to 2 wt%, the room-temperature tensile strength raised from 141 to 353 MPa. The grain size of the W-K-TiC alloys decreased sharply from 2.56 μm to 330 nm with the enhanced TiC doping. The resistance to thermal shock damage of W-K-TiC alloys was improved slightly with the increased TiC addition. Keywords: Potassium-doped tungsten, Titanium carbide, Spark plasma sintering, Tensile strength, Thermal shock

Aim: To compare the effects of the liquid-isolating maneuver and the lever-elevating maneuver in protecting cervical structures during microwave ablation for treating high-risk benign thyroid nodules. Methods: This prospectively study was approved by the Medical Ethics Committee of Panzhihua Central Hospital. A total of 174 patients were enrolled and randomly assigned to a liquid-isolating maneuver group (LIM, n = 87) or a lever-elevating maneuver group (LEM, n = 87). Operation time, postoperative voice change, time to recovery of baseline voice, peri-thyroid hematoma, neck tension, and intraoperative vasovagal reaction were assessed. Results: Operation time was greater in the LIM group than in the LEM group (44.75 ± 13.14 vs. 32.87 ± 10.84 min; p = .017).Voice changes were observed in 6 patients in the LIM group and 2 in the LEM group (6.9% vs. 2.3%, p = .278). The time to recovery of baseline voice was significantly greater in the LIM group compared with the LEM group (36.15 ± 10.24 vs. 24.48 ± 11.53 days, p = .014). The incidences of peri-thyroid hematoma and neck tension were higher in the LIM than in the LEM group (11.5% vs. 3.4%, 10.3% vs. 2.3%, p = .044 and p = .029). One patient (1.1%) in the LEM group and none of the patients in the LIM group experienced a vasovagal response (p = 1.000). Conclusion: The lever-elevating method is feasible and effective for the microwave ablation of benign thyroid nodules, with better protection of neck structures than observed with the liquid-isolating method.

In order to investigate the dynamic characteristics of blunt aircraft mounted with aerospikes and aerodisks in large-amplitude force-pitching, the Roe spatial scheme and the lower-upper symmetric Gauss-Seidel (LU-SGS) method with dual time step are employed for discretization of unsteady Navier-Stokes (N-S) equations. A parametric investigation on the flow fields is conducted by altering the pitching period, aerospike length, and aerodisk diameter consequently via a variable-controlling procedure. Dynamic characteristics of aerodynamic drag as well as the visualization of unsteady flow fields are achieved, and the results show that the aerodynamics of hypersonic aircraft under the condition of large-amplitude force-pitching vibration have hysteresis characteristics affected by periods of force-pitching vibration. In addition, when changing aerospike length and aerodisk diameter, the variation tendency of drag reduction efficiency is determined by the pitching angle of the oscillation process.

Background: Increasing lncRNAs are found to be involved in the biological process of multiple cancer types. Herein, we aimed to reveal the role of LOXL1-AS1 in endometrial cancer (EC) progression. Methods: Tumor and corresponding normal tissues were obtained from EC patients. Si-LOXL1-AS1 and miR-28-5p inhibitor were transfected to downregulate the expressions of LOXL1-AS1 and miR-28-5p, while miR-28-5p mimics were used to upregulate the miR-28-5p expression. CCK-8 and colony assays were applied to estimate the cell proliferation. Flow cytometry was performed to measure the cell apoptosis. Wound healing and transwell assays were conducted to assess the cell migration and invasion abilities. Informatics analysis was used to explore the relationship among LOXL1-AS1, miR-28-5p and RAP1B. Results: LOXL1-AS1 was found markedly up-regulated in EC tissues and cell lines. LOXL1-AS1 knockdown displayed evident suppression in cell proliferation, migration and invasion, as well as promotion in cell apoptosis. Moreover, the LOXL1-AS1 induced regulatory effects on EC cells were partially reversed by miR-28-5p inhibitor. Mechanistically, LOXL1-AS1 competitively bond to miR-28-5p, resulting in upregulation of RAP1B. Additionally, in vivo study confirmed the findings discovered in vitro. Conclusions: In summary, LOXL1-AS1 exerted oncogenic roles in EC progression by sponging miR-28-5p and thereby upregulating RAP1B. This finding might provide potential targets for EC therapy.

Baicalein (BAI) is an acknowledged flavonoids compound, which is regarded as a useful therapeutic pharmaceutical for numerous cancers. However, its involvement in melanoma is largely unknown. This study aimed to examine the anti-melanoma function of BAI and unraveled the regulatory mechanism involved. A375 and SK-MEL-28 were treated with BAI for 24 h. Then, CCK-8 assay, flow cytometry, and transwell assay were carried out to investigate cell growth, migration, and invasion. RT-qPCR was applied to detect the expression of colon cancer associated transcript-1 (CCAT1) in melanoma tissues and cells. The functions of CCAT1 in melanoma cells were also evaluated. Western blot was utilized to appraise Wnt/β-catenin or MEK/ERK pathways. BAI restrained cell proliferation and stimulated cell apoptotic capability of melanoma by suppressing cleaved-caspase-3 and cleaved-PARP. Cell migratory and invasive abilities were restrained by BAI via inhibiting MMP-2 and vimentin. CCAT1 was over-expressed in melanoma tissues and down-regulated by BAI in melanoma cells. Overexpressed CCAT1 reversed the BAI-induced anti-growth, anti-migratory, and anti-invasive effects. Furthermore, BAI inhibited Wnt/β-catenin and MEK/ERK pathways-axis via regulating CCAT1. Our study indicated that BAI blocked Wnt/β-catenin and MEK/ERK pathways via regulating CCAT1, thereby inhibiting melanoma cell proliferation, migration, and invasion.

Bone morphogenetic protein 15 (BMP15) is strongly associated with animal reproduction and woman reproductive disease. As a multifunctional oocyte-specific secret factor, BMP15 controls female fertility and follicular development in both species-specific and dosage-sensitive manners. Previous studies found that BMP15 played a critical role in follicular development and ovulation rate in mono-ovulatory mammalian species, especially in sheep and human, but study on knockout mouse model implied that BMP15 possibly has minimal impact on female fertility of poly-ovulatory species. However, this needs to be validated in other poly-ovulatory species. To investigate the regulatory role of BMP15 on porcine female fertility, we generated a BMP15-knockdown pig model through somatic nuclear transfer technology. The BMP15-knockdown gilts showed markedly reduced fertility accompanied by phenotype of dysplastic ovaries containing significantly declined number of follicles, increased number of abnormal follicles, and abnormally enlarged antral follicles resulting in disordered ovulation, which is remarkably different from the unchanged fertility observed in BMP15 knockout mice. Molecular and transcriptome analysis revealed that the knockdown of BMP15 significantly affected both granulosa cells (GCs) and oocytes development, including suppression of cell proliferation, differentiation, and follicle stimulating hormone receptor (Fshr) expression, leading to premature luteinization and reduced estradiol (E2) production in GCs, and simultaneously decreased quality and meiotic maturation of oocyte. Our results provide in vivo evidence of the essential role of BMP15 in porcine ovarian and follicular development, and new insight into the complicated regulatory function of BMP15 in female fertility of poly-ovulatory species.

Small multi-rotor unmanned aerial vehicles (SMR-UAVs) are a promising platform for low-cost synthetic aperture radar (SAR) systems. However, SMR-UAVs usually suffer from serious position errors due to their unstable motion and low actuary position sensors, and autofocus is an indispensable step for their high-quality imaging. An efficient back-projection autofocus method is proposed for SMR-UAV SAR systems by the principle of minimum entropy. The position error estimation model via minimum entropy is derived. The conjugate-gradient method is used to efficiently estimate the position errors. Moreover, to improve the computing efficiency, the strong scatterer areas are estimated as the input of entropy estimation. The effectiveness of the algorithm is demonstrated using both simulation and experimental data.

A high level of HER2 expression in breast cancer correlates with a higher tumor growth rate, high metastatic potential, and a poor long-term patient survival rate. Pertuzumab, a human monoclonal antibody, can reduce the effect of HER2 overexpression by preventing HER2 dimerization. In this study, a combination protocol of molecular dynamics modeling and MM/GBSA binding free energy calculations was applied to design peptides that interact with HER2 based on the HER2/pertuzumab crystal structure. Based on a β hairpin in pertuzumab from Glu46 to Lys65-which plays a key role in interacting with HER2-mutations were carried out in silico to improve the binding free energy of the hairpin that interacts with the Phe256-Lys314 of the HER2 protein. Combined the use of one-bead-one-compound library screening, among all the mutations, a peptide (58F63Y) with the lowest binding free energy was confirmed experimentally to have the highest affinity, and it may be used as a new probe in diagnosing and treating HER2-positive breast cancer.

In this paper, a novel improved Antlion optimization algorithm (IALO) has been proposed for solving three different IEEE power systems of optimal reactive power dispatch (ORPD) problem. Such three power systems with a set of constraints in transmission power networks such as voltage limitation of all buses, limitations of tap of all transformers, maximum power transmission limitation of all conductors and limitations of all capacitor banks have given a big challenge for global optimal solution search ability of the proposed method. The proposed IALO method has been developed by modifying new solution generation technique of standard antlion optimization algorithm (ALO). By optimizing three single objective functions of systems with 30, 57 and 118 buses, the proposed method has been demonstrated to be more effective than ALO in terms of the most optimal solution search ability, solution search speed and search stabilization. In addition, the proposed method has also been compared to other existing methods and it has obtained better results than approximately all compared ones. Consequently, the proposed IALO method is deserving of a potential optimization tool for solving ORPD problem and other optimization problems in power system optimization fields.

Improving the efficacy of nanoparticles (NPs) delivery to tumors is critical for cancer diagnosis and therapy. In our previous work, amphiphilic peptide APPA self-assembled nanocarriers were designed and constructed for cargo delivery to tumors with high efficiency. In this study, we explore the use of APPA self-assembled peptosomes as a nanoparticle adjuvant to enhance the delivery of nanoparticles and antibodies to integrin αvβ3 and neuropilin-1 (NRP1) positive tumors. The enhanced tumor delivery of coadministered NPs was confirmed by better magnetosome (Mag)-based T2-weighted magnetic resonance imaging (MRI), liposome-based fluorescence imaging, as well as the improved anti-tumor efficacy of monoclonal antibodies (trastuzumab in this case) and doxorubicin (DOX)-containing liposomes. Interestingly, the improvement is most significant for the delivering of compounds that have active or passive tumor targeting ability, such as antibodies or NPs that have enhanced permeability and retention (EPR) effect. However, for non-targeting small molecules, the effect is not significant. In vitro and in vivo studies suggest that both peptosomes and the coadministered compounds might be internalized into cells through a NRP1 mediated co-endocytosis (CoE) pathway. The improved delivery of coadministered NPs and antibodies to tumors suggests that the coadministration with APPA self-assembled peptosomes could be a valuable approach for advancing αvβ3 and NRP1 positive tumors diagnosis and therapy.

Plant 14-3-3 proteins act as critical components of various cellular signaling processes and play an important role in regulating multiple physiological processes. However, less information is known about the 14-3-3 gene family in banana. In this study, 25 14-3-3 genes were identified from the banana genome. Based on the evolutionary analysis, banana 14-3-3 proteins were clustered into ε and non-ε groups. Conserved motif analysis showed that all identified banana 14-3-3 genes had the typical 14-3-3 motif. The gene structure of banana 14-3-3 genes showed distinct class-specific divergence between the ε group and the non-ε group. Most banana 14-3-3 genes showed strong transcript accumulation changes during fruit development and postharvest ripening in two banana varieties, indicating that they might be involved in regulating fruit development and ripening. Moreover, some 14-3-3 genes also showed great changes after osmotic, cold, and salt treatments in two banana varieties, suggested their potential role in regulating banana response to abiotic stress. Taken together, this systemic analysis reveals the involvement of banana 14-3-3 genes in fruit development, postharvest ripening, and response to abiotic stress and provides useful information for understanding the functions of 14-3-3 genes in banana.

A feasible control strategy is proposed to control a doubly fed induction generator based on the wind energy converter system (DFIG-WECS). The main aim is to enhance the steady state and dynamic performance under the condition of the parameter perturbations and external disturbances and to satisfy the stator power response of the system. Within the proposed control method, the control scheme for the rotor side converter (RSC) is developed on the model predictive control. Firstly, the self-adaptive reference trajectory is established from the deduced discrete state-space equation of the generator. Then, the rotor voltage is calculated by minimizing the global performance index under the current prediction steps at the sampling instant. Through the control scheme for the grid side converter (GSC) and wind turbine, we have re-applied the conventional control. The effectiveness of the proposed control strategy is verified via time domain simulation of a 150 kW-575 V DFIG-WECS using Matlab/Simulink. The simulation result shows that the control of the DFIG with the proposed control method can enhance the steady and dynamic response capability better than the conventional ones when the system faces errors due to the parameter perturbations, external disturbances and the rotor speed.

The position of RFID-tagged objects in sensor networks is becoming an important feature for ubiquitous computing applications. In this work, we develop an improved positioning algorithm for RFID-tagged objects. Compared with the VIRE algorithm, we apply a nonlinear interpolation method to further improve the positioning precision. We also introduce the concept of credibility of reference tags to reduce the influence of abnormal tags on positioning precision. Finally, we provide detailed simulations to evaluate the proposed technique.

The purpose of this study is to investigate the current status of metal pollution of the sediments from urban-stream, estuary and Jinzhou Bay of the coastal industrial city, NE China. Forty surface sediment samples from river, estuary and bay and one sediment core from Jinzhou bay were collected and analyzed for heavy metal concentrations of Cu, Zn, Pb, Cd, Ni and Mn. The data reveals that there was a remarkable change in the contents of heavy metals among the sampling sediments, and all the mean values of heavy metal concentration were higher than the national guideline values of marine sediment quality of China (GB 18668-2002). This is one of the most polluted of the world's impacted coastal systems. Both the correlation analyses and geostatistical analyses showed that Cu, Zn, Pb and Cd have a very similar spatial pattern and come from the industrial activities, and the concentration of Mn mainly caused by natural factors. The estuary is the most polluted area with extremely high potential ecological risk; however the contamination decreased with distance seaward of the river estuary. This study clearly highlights the urgent need to make great efforts to control the industrial emission and the exceptionally severe heavy metal pollution in the coastal area, and the immediate measures should be carried out to minimize the rate of contamination, and extent of future pollution problems.

Background. Intravenous ketorolac and metoclopramide are common emergency treatments for adult patients with migraine headaches. The comparison between ketorolac and metoclopramide for migraine treatment is an intriguing issue for research and clinical practice. Objectives. To provide an updated systematic review and meta-analysis of randomized clinical trials (RCTs) to help determine which treatment has better effects for migraine patients. Materials and methods. Intravenous ketorolac and metoclopramide were compared to evaluate whether intravenous ketorolac is associated with significant benefits for pain intensity, short-term headache relief and sustained headache relief among adult patients with migraines. Adverse effects were also analyzed. Five studies with a total of 674 adult patients were included in the analysis, which focused on the outcomes of pain intensity, short-term headache relief, sustained headache relief, and adverse effects. Results. The meta-analysis showed that the only modest but statistically significant difference was present in short-term headache relief when comparing intravenous ketorolac with intravenous metoclopramide. There were no significant differences between intravenous ketorolac and metoclopramide in terms of pain intensity, sustained headache relief or adverse effects. Conclusions. The results suggest that there are no significant differences in most treatment effects (aside from short-term headache relief) and adverse effects when comparing intravenous ketorolac with intravenous metoclopramide. However, the paucity of literature on this topic might have limited the interpretation of the current results. Thus, more relevant studies are warranted. [ABSTRACT FROM AUTHOR]