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Artificial intelligence has made significant breakthroughs in many fields, especially with the broad deployment of edge devices, which provides opportunities to develop and apply various intelligent models in edge networks. Edge device-server co-inference system has gradually become the mainstream of edge intelligent computing. However, the existing feature procession works in the edge inference framework neglect the focus on whether features are important, and the processed features are still redundant, affecting the inference efficiency. In this paper, we propose a novel attention-based variable-size feature compression module to enhance edge systems' inference efficiency by leveraging input data's varying importance levels. First, a multi-scale attention mechanism is introduced, which operates jointly in the channel spatial to effectively compute importance weights from the intermediate output features of the edge devices. These weights are then utilized to assign different transmission probabilities, filtering out irrelevant feature data and prioritizing task-relevant information. Second, the new loss algorithm and progressive model training strategy are designed to optimize the proposed module, enabling the model to adapt to the reduced feature data gradually and effectively. Finally, experimental results on CIFAR-10 and ImageNet datasets demonstrate the effectiveness of our proposed solution, showcasing a significant reduction in the data output volume of edge devices and minimizing communication overhead while ensuring minimal loss in model accuracy. [ABSTRACT FROM AUTHOR]

Electrochemical discharge machining (ECDM), as a new type of non-traditional machining method, is widely used in the machining of insulating hard and brittle materials such as glass and ceramics. However, there are some problems such as difficulty in circulating electrolyte, resulting in poor quality machining of deep and small holes. In this paper, electrochemical discharge machining with ultrasonic vibration and tube electrode is used to improve the flow field in the machining gap and enhance the machining quality by using the injected electrolyte inside the tube electrode and ultrasonic vibration. First, the temperature distribution state of electrochemical discharge is simulated, and the influence of the coupling effect of the electrolyte injection and ultrasonic vibration on the machining gap is analyzed. And then, the influence weights of each factor were analyzed by orthogonal experiments and further analyzed to obtain the optimized combination of machining parameters, which reduced the entrance size of small holes by 19.3%, increased the machining depth by 18.5% and increased the depth-to-diameter ratio by 46.2% compared with the traditional ECDM. The effect of ultrasonic vibration was studied on the basis of the optimized machining parameters. The results show that the optimized effect of ultrasonic vibration with an amplitude of 7μm is most obvious under the conditions of low pressure and low injection rate. Finally, with the optimized machining parameters, a 5×5 array of small holes and three deep and small holes were machined, demonstrating that electrochemical discharge machining with ultrasonic vibrating tube electrode can be an efficient and high-quality method for machining small holes. [ABSTRACT FROM AUTHOR]

Efficient decomposition of ammonium perchlorate (AP) which is the oxidant and combustion adjuvant of the solid propellants is critical for the fast ignition and high-speed liftoff of the rocket. We synthesize Co metal-decorated carbon nanotubes (Co/CNTs) as an advanced catalyst to promote the sufficient thermal decomposition of AP under reduced temperature. The results indicate that Co/CNTs effectively accelerate the decomposition of AP by reducing the thermal decomposition temperature from 430.0 to 309.9 ℃ and achieve a 3-times higher thermal releasing than that of the pure AP. The acid-etching comparison test reveals that decreasing the cobalt content in Co/CNTs does not affect the decomposition temperature of AP but suppress the decomposition heat releasing. It is proposed that the CNTs boost fast electron transfer during the AP decomposition and the cobalt works as an active additive to increase the heat releasing. This work provides an insight into the electron-transfer mechanism for the thermal decomposition of AP and a valuable guidance for developing advanced combustion catalysts used in the solid propellants. [ABSTRACT FROM AUTHOR]

In this paper, a typical experiment is carried out based on a high-resolution air-sea coupled model, namely, the coupled ocean-atmosphere-wave-sediment transport (COAWST) model, on both heterogeneous many-core (SW) and homogenous multicore (Intel) supercomputing platforms. We construct a hindcast of Typhoon Lekima on both the SW and Intel platforms, compare the simulation results between these two platforms and compare the key elements of the atmospheric and ocean modules to reanalysis data. The comparative experiment in this typhoon case indicates that the domestic many-core computing platform and general cluster yield almost no differences in the simulated typhoon path and intensity, and the differences in surface pressure (PSFC) in the WRF model and sea surface temperature (SST) in the short-range forecast are very small, whereas a major difference can be identified at high latitudes after the first 10 days. Further heat budget analysis verifies that the differences in SST after 10 days are mainly caused by shortwave radiation variations, as influenced by subsequently generated typhoons in the system. These typhoons generated in the hindcast after the first 10 days attain obviously different trajectories between the two platforms. [ABSTRACT FROM AUTHOR]

Concrete repair and rehabilitation prolong the effective service lives of structures and are important topics in the building field worldwide. Epoxy latex-modified cementitious materials have shown promise for a number of applications in building and construction, but the mix design processes remain arbitrary because their pore structures are not well understood. Porosity and pore size distributions are pore structure parameters that have direct effects on the mechanical properties and durability of concrete. In this paper, mercury intrusion porosimetry (MIP) was used to analyze the porosities and pore size distributions of epoxy latex-modified mortars. The effects of the polymer-to-cement ratio on the pore structures of epoxy latex-modified mortars were investigated. Mortars with polymer-to-cement ratios of 0%, 5%, 10%, 15%, and 20% were cured for 7, 28, 60, and 90 days in this study. Images of specimen microstructures were obtained by scanning electron microscopy (SEM), which showed that increases in the amount of epoxy latex added caused the proportion of micropores in the mortar to decrease, while the proportion of macropores and gel pores increased. The pore size distribution of epoxy latex-modified mortar was described with a composite logarithmic model. Relationships between the pore size distribution and the polymer-to-cement ratio and the curing age were obtained. The method described herein might be sufficiently accurate and convenient to evaluate or predict the pore size distribution of an epoxy latex-modified mortar, i.e., by determining the statistical distribution and analyzing the probability. The process for design of the polymer concrete mix ratio will be facilitated by methods that accurately describe the structure of the epoxy latex-modified mortar. [ABSTRACT FROM AUTHOR]

Non-adiabatic behaviour induced by the chorus-electron interaction is an important contributor to the radiation belt dynamics, and largely relies on wave frequency distribution. During the geomagnetic storm on August 2, 2016, upper-band, lower-band and extremely low frequency (ELF) chorus waves were simultaneously observed within one orbit period of the Van Allen Probe B. Numerical simulations are performed to investigate the electron evolution by the observed chorus with different frequencies. The results show that various frequency chorus waves have different effects on electron dynamics. For chorus in the range f≈0.3fce−0.7fce, energy diffusion is the dominant process in electron evolutions. For chorus in the range 0.1fce⩽f⩽0.25fce, the pitch angle diffusion tends to be comparable to energy diffusion for Ek>0.5 MeV. For ELF chorus below 0.1fce, the pitch angle diffusion rate is much above the energy diffusion rate, leading to potential scattering losses. [ABSTRACT FROM AUTHOR]

A novel monocular visual simultaneous localization and mapping (SLAM) algorithm built on the semi-direct method is proposed to deal with some problems in complex environments, such as low-texture, moving objects and perceptual aliasing. The proposed algorithm takes advantage of direct and feature-based methods. On one hand, a direct method is used to track the camera poses and solve the feature alignment. On the other hand, ORB features in keyframes are extracted and matched for optimization and loop closure. To improve the localization accuracy in dynamic environments, a motion detection module that is robust to illumination change is adopted. In addition, for the sake of resolving the loop closure detection problem in perceptual aliasing scenes, this paper fuses the spatial information between two visual words into the bag of visual words (BoVW) model and employs an improved pyramid term frequency-inverse document frequency (TF-IDF) scoring match scheme. Experimental results prove that the proposed algorithm behaves better performance than ORB-SLAM with regard to overall accuracy and speed in complex environments. [ABSTRACT FROM AUTHOR]

In December 2019, pneumonia of unknown cause occurred in Wuhan, Hubei Province, China. On 7 January 2020, a novel coronavirus, named as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), was identified in the throat swab sample of one patient. The World Health Organization (WHO) announced the epidemic disease caused by SARS-CoV-2 as coronavirus disease 2019 (COVID-19). Currently, COVID-19 has spread widely around the world, affecting more than seventy countries. China, with a huge burden of this disease, has taken strong measures to control the spread and improve the curative rate of COVID-19. In this review, we summarized the epidemiological characteristics, clinical features, diagnosis, treatment, and prognosis of COVID-19. A comprehensive understanding will help to control the disease. [ABSTRACT FROM AUTHOR]

The development of low-temperature aluminum electrolysis makes it possible to reduce energy consumption and greenhouse gas emissions. The KF-NaF-AlF3-based electrolyte is a promising low-temperature electrolyte for aluminum reduction. The liquidus temperatures of KF-NaF-AlF3 electrolytes with a total cryolite ratio (CRt) fixed at 1.3–2.0, and with different concentrations of NaF (with a step change of 5 mol.%), were investigated by the cooling curve method. The results showed that the liquidus temperature of KF-NaF-AlF3 mixtures increases with the increase of the CRt, which has a bigger influence on the liquidus temperature than the traditional NaF-AlF3 electrolyte currently used in aluminum smelters. When the content of NaF is 10–20 mol.%, the curves of the liquidus temperature vs. NaF content reach a peak. When the NaF content ranges from 30 to 40 mol.%, the liquidus temperature is relatively low (695–900°C). The precipitated order of the compounds in molten KF-NaF-AlF3 electrolytes with a CRt of 1.3 is as follows: K2NaAlF6 (or K3AlF6) → Na3Al5F14 → K2NaAl3F12 → KAlF4. [ABSTRACT FROM AUTHOR]

A series of MnCoOx flower-like hollow microspheres with various molecular proportions of reactant were prepared through simple solvothermal method for the ammonia selective catalytic reduction (SCR) at low temperatures. The as-prepared samples have been applied by various characterization techniques to explore the formation process of the morphology and physicochemical properties. The Mn(1)Co(1)Ox presented the optimal intrinsic catalytic performance (95% NOx conversion at 75 °C), favorable thermal stability, and strong SO2 resistance. The excellent properties mainly related to its higher specific surface area and abundant active sites originated from hollow microsphere special structure consists of abundant nanosheets, robust redox properties beneficial for the strong interaction between the manganese and cobalt, larger number of acidic sites and stronger acid strength, etc., which collaboratively dominate its catalytic properties of NH3-SCR at low temperatures. [ABSTRACT FROM AUTHOR]

The pathogenesis of late-onset Alzheimer's disease (LOAD) mainly involves abnormal accumulation of extracellular β-amyloid (Aβ) and the consequent neurotoxic effects. The triggering receptor expressed on myeloid cells 2 (TREM2) gene is associated with the pathogenesis of LOAD and plays important roles in mediating the phagocytosis of Aβ by microglia and regulating inflammation in central nervous system. However, the exact mechanisms of these processes have not yet been clarified. In this study, we investigated the mechanism by which TREM2 regulates neuroinflammation and promotes Aβ1-42 clearance by BV-2 cells and further elucidated the underlying molecular mechanisms. We either silenced or overexpressed TREM2 in BV-2 cells and evaluated the cell viability, Aβ1-42 content, and expression of inflammatory markers (IL-1β, IL-6, and TNF-α). TREM2 overexpression up-regulated cell activity, promoted clearance of Aβ1-42 by BV-2 cells, and down-regulated expression of the inflammatory factors. In addition, TREM2 overexpression downregulation the expression of the TLR family (TLR2, TLR4 and TLR6) in BV-2 cells. Moreover, LPS, as an agonist of the TLR family, up-regulated the expression of inflammatory cytokines (IL-1β, TNF-α, and IL-6) in BV-2 cells overexpressing TREM2. In conclusion, TREM2 promoted clearance of Aβ1-42 by BV-2 cells and restored BV-2 cell viability from Aβ1-42-mediated neuroinflammation by downregulating TLRs. These findings suggest that TREM2 may be a target for LOAD therapy. [ABSTRACT FROM AUTHOR]

The cryolite ratio (CR) is an important parameter for the electrolyte in aluminum reduction cells. The measurement method for the CR of the KF-NaF-AlF3 system acid (CR < 3) electrolyte by means of electrical conductivity was initially developed, and the formula for calculating the CR was deduced. This method has the advantages of simple operation and high precision. In addition, the relative standard deviations (RSD) of the measurement are < 1.2 pct, and the analysis error of the NaF or KF content has little effect on the determination of the CR. [ABSTRACT FROM AUTHOR]

Cells need to appropriately balance transcriptional stability and adaptability in order to maintain their identities while responding robustly to various stimuli. Eukaryotic cells use an elegant “epigenetic” system to achieve this functionality. “Epigenetics” is referred to as heritable information beyond the DNA sequence, including histone and DNA modifications, ncRNAs and other chromatin-related components. Here, we review the mechanisms of the epigenetic inheritance of a repressive chromatin state, with an emphasis on recent progress in the field. We emphasize that (i) epigenetic information is inherited in a relatively stable but imprecise fashion; (ii) multiple cis and trans factors are involved in the maintenance of epigenetic information during mitosis; and (iii) the maintenance of a repressive epigenetic state requires both recruitment and self-reinforcement mechanisms. These mechanisms crosstalk with each other and form interconnected feedback loops to shape a stable epigenetic system while maintaining certain degrees of flexibility. [ABSTRACT FROM AUTHOR]

Altered gravity, especially microgravity affects cellular functions of immune cells and can result in immune dysfunction for long-term, manned spaceflight and space exploration. The underlying mechanism, however, of sensing and responding to the gravity alteration is poorly understood. Here, a rotary cell culture system (RCCS) bioreactor was used to elucidate the effects of simulated microgravity on polymorphonuclear neutrophils (PMN)-like HL-60 cells. Alteration of cell morphology, up-regulation of (nitric oxide) NO production, enhancement of interleukin-6 (IL-6), interleukin-8 (IL-8), and monocyte chemotactic protein 1 (MCP-1) secretion, and diversity of cellular adhesion molecule expression were observed for the cells cultured in RCCS, leading to the up-regulated inflammatory immune responses and host defense. It was also indicated that such alterations in biological responses of PMNs mediated the reduced rolling velocity and decreased adhesion of PMN-like HL-60 cells on endothelial cells under shear flow. This work furthers the understandings in the effects and mechanism of microgravity on PMN functions, which are potentially helpful for optimizing the countermeasures to immune suppression in the future long-term, manned spaceflight. [ABSTRACT FROM AUTHOR]

Drought is a great concern in agricultural yield. Super-absorbent polymers (SAPs) can assist in easing water shortage. Therefore, it is significantly important to study the water absorbing and desorbing capacity of SAPs when applied into soil as well as their effective time. The aim of this study was to investigate the effect of different SAP types under the same moisture condition and the effect of the same SAP type under different moisture conditions on saturated soil water content, saturated soil hydraulic conductivity and soil water diffusivity. With SAP application, saturated soil water volumetric content increased significantly, up to 0.186 cm cm, while saturated hydraulic conductivity and diffusivity significantly decreased because the soil pores were blocked by SAP's swelling volume during the repeated wetting and drying cycles. After SAPs were mixed in the soil, their capacity of absorbing and desorbing water showed a downward trend with time and outside water condition. Under a relatively stable water condition, such capacity reduced more slowly. As for the soil with SAP application, successful simulation for diffusivity D( θ, T) was also applicable to other parameters of the equation of water movement, which made it possible to study the water movement under the same condition. [ABSTRACT FROM AUTHOR]

Model tests and numerical analyses of stepped reinforced retaining wall were performed to investigate the effects of rheology of backfill and creep of geogrids on the long-term performance of the structure. The geogrid tensions, soil pressures, wall deformations and foundation pressure were measured during model construction and loading. A visco-elasto-plastic model and an empirical nonlinear visco-elastic model were utilized to simulate the stresses and deformations of geogrid-reinforced earth-retaining wall under long-term loads. By comparing test data with numerical results, it is shown that the foundation pressure distribution is nonlinear, and the lateral constraint of geogrids for backfill can cause a redistribution of foundation pressure. The curve of soil pressure is outside convex at each step initially, and it is close to the distribution for the case of vertical wall subsequently. The variation trend of geogrid tensions at different heights is obtained. Moreover, the failure mechanism and development mode of potential slip surface in retaining wall are proposed. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

The article titled "TREM2 Attenuates Aβ1‑42‑Mediated Neuroinflammation in BV‑2 Cells by Downregulating TLR Signaling", written by Huiping Long, Gang Zhong, Chengzhi Wang, Jian Zhang, Yueling Zhang, Jinglian Luo, Shengliang Shi, was originally published electronically on the publisher's internet portal (currently SpringerLink) on 27 May 2019 with open access. [ABSTRACT FROM AUTHOR]

In this study, the concentrations of nine typical antibiotics, including sulfadiazine (SD), sulfamerazine (SMR), sulfamethazine (SM2), sulfamethoxazole (SMZ), ofloxacin (OFX), ciprofloxacin (CIP), trimethoprim (TMP), oxytetracycline (OTC), and tetracycline hydrochloride (TC), were detected in the Yitong River by solid-phase extraction high-performance liquid chromatography. The concentrations of the antibiotics were analyzed. Additionally, an improved immobilized substrate enzyme substrate method (DST-enzyme substrate method) was developed and used to evaluate the antibiotic resistance of coliform bacteria to OFX, CIP, enrofloxacin (ENR), TC, sulfisoxazole (SOX), and TMP in the Yitong River. The results showed that the concentrations of the nine antibiotics ranged from nd (not detected) to 1.361 μg/L. The detection rate and concentration of OFX were the highest, followed by CIP, and the detection rate and concentration of SM2 and OTC were the lowest. The detection rate and concentrations of antibiotics were higher in August and November than those in May. The antibiotics were mainly distributed in the livestock sewage discharge and suburban domestic sewage discharge areas. Moreover, the drug resistance of total coliform bacteria to fluoroquinolones, sulfonamides, tetracyclines, and TMP varied with season. [ABSTRACT FROM AUTHOR]

This study aimed at developing simple, sensitive and rapid electrochemical approach to quantitatively determine and assess the toxicity of 2,4-dichlorophenol (2,4-DCP), a priority pollutant and has potential risk to public health through a novel poly(eosin Y, EY)/hydroxylated multi-walled carbon nanotubes composite modified electrode (PEY/MWNTs-OH/GCE). The distinct feature of this easy-fabricated electrode was the synergistic coupling effect between EY and MWNTs-OH that enabled a high electrocatalytic activity to 2,4-DCP. Under optimum conditions, the oxidation peak current enhanced linearly with concentration increasing from 0.005 to 0.1 μM and 0.2 to 40.0 μM, and revealed the detection limit of 1.5 nM. Moreover, the PEY/MWNTs-OH/GCE exhibited excellent electrocatalytic activity toward intracellular electroactive species. Two sensitive electrochemical signals ascribed to guanine/xanthine and adenine/hypoxanthine in human hepatoma (HepG2) cells were detected simultaneously. The sensor was successfully applied to evaluate the toxicity of 2,4-DCP to HepG2 cells. The IC50 values based on the two electrochemical signals are 201.07 and 252.83 μM, respectively. This study established a sensitive platform for the comprehensive evaluation of 2,4-DCP and posed a great potential to simplify environmental toxicity monitoring. [ABSTRACT FROM AUTHOR]