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Drug adulteration and contamination are serious threats to human health therefore, their accurate monitoring is very important. Allopurinol (Alp) and theophylline (Thp) are commonly used drugs for the treatment of gout and bronchitis, while their isomers hypoxanthine (Hyt) and theobromine (Thm) have no effect and affect the efficacy of the drug. In this work, the drug isomers of Alp/Hyt and Thp/Thm are simply mixed with α-, β-, γ-cyclodextrin (CD) and metal ions and separated using trapped ion mobility spectrometry-mass spectrometry (TIMS-MS). TIMS-MS results showed that Alp/Hyt and Thp/Thm isomers could interact with CD and metal ions and form corresponding binary or ternary complexes to achieve their TIMS separation. Different metal ions and CDs showed different separation effect for the isomers, among which Alp and Hyt could be successfully distinguished from the complexes of [Alp/Hyt+γ-CD + Cu–H](+) with separation resolution (R(P–P)) of 1.51; whereas Thp and Thm could be baseline separated by [Thp/Thm+γ-CD + Ca–H](+) with R(P–P) of 1.96. Besides, chemical calculations revealed that the complexes were in the inclusion forms, and microscopic interactions were somewhat different, making their mobility separation. Moreover, relative and absolute quantification was investigated with an internal standard to determine the precise isomers content, and good linearity (R(2) > 0.99) was obtained. Finally, the method was applied for the adulteration detection where different drugs and urine were analyzed. In addition, due to the advantages of fast speed, simple operation, high sensitivity, and no chromatographic separation required, the proposed method provides an effective strategy for the drug adulteration detection of isomers.

In advanced aero-propulsion engines, kerosene is often injected into the combustor at supercritical pressures, where flow dynamics is distinct from the subcritical counterpart. Large-eddy simulation combined with real-fluid thermodynamics and transport theories of a N-dodecane jet in oxygen crossflow at supercritical pressures is presented. Liquid dodecane at 600 K is injected into a supercritical oxygen environment at 700 K at different supercritical pressures and jet-to-crossflow momentum flux ratios (J). Various vortical structures are discussed in detail. The results shown that, with the same jet-to-crossflow velocity ratio of 0.75, the upstream shear layer (USL) is absolutely unstable at 6.0 MPa (J = 7.1) and convectively unstable at 3.0 MPa (J = 13.2). This trend is consistent with the empirical criterion for the stability characteristics of a jet in crossflow at subcritical pressures (Jcr = 10). While decreasing J to 7.1 at 3.0 MPa, however, the dominant Strouhal number of the USL varies along the upstream jet trajectory, and the USL becomes convectively unstable. Such abnormal change in stability behavior can be attributed to the real-fluid effect induced by strong density stratification at pressure of 3.0 MPa, under which a point of inflection in the upstream mixing layer renders large density gradient and tends to stabilize the USL. The stability behavior with varying pressure and J is further corroborated by linear stability analysis. The analysis of spatial mixing deficiencies reveals that the mixing efficiency is enhanced at a higher jet-to-crossflow momentum flux ratio.

Image-to-image translation translates an image from one domain to another. The goal is to learn the translation relationship between different image domains. Compared with the translation models to be trained using paired training data, CycleGAN has the advantage of learning to translate between domains without paired input–output training examples. However, when using CycleGAN to translate images among multiple domains, the complexity of the model increases nonlinearly with the number of domains. To reduce the model complexity of CycleGAN-based translation models, we assume that there is a hidden space shared by different domains, and this space stores the common features of images. Then, we design a common encoder to learn image features in the hidden space. Based on the hidden space, we propose a translation model that scales linearly with the number of domains. To further improve the common feature representation accuracy, we introduce the adversarial component in the hidden space to learn the common features. We test the proposed models on different datasets, including painting style and season transfer datasets and achieve good results.

BackgroundBread wheat (Triticum aestivum) is an allohexaploid that is generated by two subsequent allopolyploidization events. The large genome size (16 Gb) and polyploid complexity impede our understanding of how regulatory elements and their interactions shape chromatin structure and gene expression in wheat. The open chromatin enrichment and network Hi-C (OCEAN-C) is a powerful antibody-independent method to detect chromatin interactions between open chromatin regions throughout the genome.ResultsHere we generate open chromatin interaction maps for hexaploid wheat and its tetraploid and diploid relatives using OCEAN-C. The anchors of chromatin loops show high chromatin accessibility and are concomitant with several active histone modifications, with 67% of them interacting with multiple loci. Binding motifs of various transcription factors are significantly enriched in the hubs of open chromatin interactions (HOCIs). The genes linked by HOCIs represent higher expression level and lower coefficient expression variance than the genes linked by other loops, which suggests HOCIs may coordinate co-expression of linked genes. Thousands of interchromosomal loops are identified, while limited interchromosomal loops (0.4%) are identified between homoeologous genes in hexaploid wheat. Moreover, we find structure variations contribute to chromatin interaction divergence of homoeologs and chromatin topology changes between different wheat species. The genes with discrepant chromatin interactions show expression alteration in hexaploid wheat compared with its tetraploid and diploid relatives.ConclusionsOur results reveal open chromatin interactions in different wheat species, which provide new insights into the role of open chromatin interactions in gene expression during the evolution of polyploid wheat.

α-Fluorinated chalcones were prepared and evaluated for their cell growth inhibitory properties against six human cancer cell lines. The most potent chalcone 4c demonstrated excellent selective toxicity against cancer cells versus normal human cells, with IC50 values at nanomolar concentration ranges against 5 cancer cell lines. A further study revealed that 4c could bind to the colchicine site of tubulin, disrupt the cell microtubule networks, and effectively inhibit tubulin polymerisation. Cellular-based mechanism studies elucidated that 4c arrested MGC-803 cell cycle at G2/M phase. In addition, 4c dose-dependently caused Caspase-induced apoptosis of MGC-803 cells through mitochondrial dysfunction. Notably, compound 4c was found to inhibit the HUVECs tube formation, migration, and invasion in vitro. Furthermore, our data suggested that treatment with 4c significantly reduced MGC-803 cells metastasis and proliferation in vitro. Overall, this work showed that chalcone hybrid 4c is a potent inhibitor of tubulin assembly with prominent anti-angiogenesis and anti-cancer properties.

Additional file 2: Supplementary Figure S1-S6.

Additional file 1: Supplementary tables S1-S3 and S7.

Additional file 11. Review history.

Additional file 8. Review history.

In the calibration system of a particle detector, it is necessary to visually locate an active light source moving in a dark environment. The active light source has a built-in lithium-ion battery, which is wirelessly charged before working, and can work continuously for 24 hours after being charging. According to this need, this paper designs and implements the wireless charging light source system. The system consists of a wireless charging control unit and a wireless light source unit. The wireless charging control unit receives instructions from the host computer to complete the charging of the wireless light source unit, and the wireless light source unit controls the on and off of the LED drive current after receiving the instructions from the control unit. After testing, the active light source can work continuously for 24 hours under the condition of being fully charged, meeting the need of visual positioning.

As organelles of the innate immune system, inflammasomes activate caspase-1 and other inflammatory caspases that cleave gasdermin D (GSDMD). Caspase-1 also cleaves inactive precursors of the interleukin (IL)-1 family to generate mature cytokines such as IL-1β and IL-18. Cleaved GSDMD forms transmembrane pores to enable the release of IL-1 and to drive cell lysis through pyroptosis1-9. Here we report cryo-electron microscopy structures of the pore and the prepore of GSDMD. These structures reveal the different conformations of the two states, as well as extensive membrane-binding elements including a hydrophobic anchor and threepositively charged patches. The GSDMD pore conduit is predominantly negatively charged. By contrast, IL-1 precursors have an acidic domain that is proteolytically removed by caspase-110. When permeabilized by GSDMD pores, unlysed liposomes release positively charged and neutral cargoes faster than negatively charged cargoes of similar sizes, and the pores favour the passage of IL-1β and IL-18 over that of their precursors. Consistent with these findings, living-but not pyroptotic-macrophages preferentially release mature IL-1β upon perforation by GSDMD. Mutation of the acidic residues of GSDMD compromises this preference, hindering intracellular retention of the precursor and secretion of the mature cytokine. The GSDMD pore therefore mediates IL-1 release by electrostatic filtering, which suggests the importance of charge in addition to size in the transport of cargoes across this large channel.

The low-yield strength steel (LYS) has been a promising material to make shear panel damper in seismic engineering due to the large plastic deformation capacity. To take advantage of the energy absorption ability of the low-yield-strength steel shear panel damper (LYSPD), it is essential to obtain the accurate prediction for the stress-strain relationship of LYS especially for the high plastic deformation. However, most of the existing constitutive models for LYS are based on the plastic strain not more than 6%. Here, an improved constitutive model is developed to describe the plastic behavior in a large range of plastic strain up to 60%. First of all, the large plastic behavior with the necking effect under monotonic tension loading is considered and verified by test. Secondly, together with several constitutive models for describing the shear plastic behavior of LYS with and without consideration of cyclic hardening, the accuracy of these models are verified by the cyclic incremental test results of LYSPD. Moreover, an accurate model is calibrated by using the yield stress evolution of the two-surface theory. The developed model could be used to describe the mechanical properties for large plastic strain and to judge the stability of the structure in improved accuracy.

Eye movements have been widely investigated to study the atypical visual attention in Autism Spectrum Disorder (ASD). The majority of these studies have been focused on limited eye movement features by statistical comparisons between ASD and Typically Developing (TD) groups, which make it difficult to accurately separate ASD from TD at the individual level. The deep learning technology has been highly successful in overcoming this issue by automatically extracting features important for classification through a data-driven learning process. However, there is still a lack of end-to-end deep learning framework for recognition of abnormal attention in ASD. In this study, we developed a novel two-stream deep learning network for this recognition based on 700 images and corresponding eye movement patterns of ASD and TD, and obtained an accuracy of 0.95, which was higher than the previous state-of-the-art. We next characterized contributions to the classification at the single image level and non-linearly integration of this single image level information during the classification. Moreover, we identified a group of pixel-level visual features within these images with greater impacts on the classification. Together, this two-stream deep learning network provides us a novel and powerful tool to recognize and understand abnormal visual attention in ASD.

The transient overvoltage appears commonly in LCC-HVDC infeed power system and could lead to tripping of adjacent PV and cascading failures, especially in the peak stage. The current solutions mainly focus on improving short circuit capacity and the response of reactive power compensation devices. However, these solutions need extra devices or could not response rapidly to the voltage peak. Thus, this paper proposes an additional emergency control strategy of PV to suppress overvoltage peak, which utilizes PV's rapid adjustment capacity. The topology of a practical system and controls of key devices are introduced first. Then, the process of transient recovery overvoltage peak is analysed. Further, an emergency control strategy is proposed. An additional signal, which is formed by the error between terminal voltage measurement and its reference, is attached to the output voltage reference of PV to provide emergency reactive power support. Finally, the feasibility and effectiveness of the proposed control strategy are validated by simulation results.

Gentisyl alcohol-type natural products, possessing various important biological properties, have been synthesized from 4-methoxyphenol by using a selective phenol monohydroxymethylation/monochlorination, a CAN oxidation and a sodium dithionite reduction as the key steps. The natural product synthesis is efficient, atom- and step-economical, and requires no protecting groups.

In this study, polydimethyl-siloxane (PDMS) film with a mushroom-shaped micropillars array was formed as both a dry adhesive patch to fix an electrode on human body and a dielectric layer of a capacitive dry electrode to sense biopotentials. The adhesion strength of the PDMS film was analyzed by numerical calculation and experimental results. The results indicated that the adhesion strength was large enough to fix the electrode on skin. Furthermore, the durability testing result demonstrated that the PDMS film had adhesion strength stability. In addition, the PDMS film was more biocompatible than the acrylic medical patch. The experimental results of biopotentials measurement presented that the qualities of electrocardiogram (ECG) and electromyogram (EMG) signals recorded by the capacitive dry electrode were comparable with those of the wet electrode (Ag/AgCl).

In recent years, various natural disasters occurred frequently, such as earthquake, typhoon, etc. These disasters constitute a great threat to the safe and stable operation of the power grid, at the same time, it also puts forward higher requirements for the rescue work of the power line post-disaster. For this reason, this paper puts forward a method for evaluating the rescue priority level of power line post-disaster based on analytic hierarchy process (AHP). This method improves the traditional analytic hierarchy process (AHP), and based on this, by application of cask theory, constructing a hierarchical structure model for rescue priority evaluation, constructing the judgment matrix, calculation of the evaluation index weigh, consistency check, dimensionless of evaluation index, calculation of rescue priority value, determination of rescue priority and a series of work, complete the evaluation of rescue priority level of power line post-disaster. This method provided decision support for rescue of power line post-disaster, greatly improved the efficiency of post-disaster rescue work, minimize the loss of economy, it is of great significance to safe operation of power grids.

Geological disasters not only on the transmission line operation and maintenance are a great threat, but also occurred geological disasters to the people, brings the serious economic loss of property and state government. We propose an algorithm based on depth convolutional neural network (CNN) and an improved region growing algorithm (RSG_R) method for detection of landslide intelligence. The first visible light transmission line inspection image establish landslide detection image data set; and then the CNN of the image data sets were detected, and get the image existence landslide set; finally use rsg_r algorithm to extract the discriminant information of the image elements of disaster disaster (area, boundary and center). The experimental results verify the validity and superiority of the algorithm in two aspects of detection accuracy and sensitivity.

In this paper, a new type of 3D bin packing problem (BPP) is proposed, in which a number of cuboid-shaped items must be put into a bin one by one orthogonally. The objective is to find a way to place these items that can minimize the surface area of the bin. This problem is based on the fact that there is no fixed-sized bin in many real business scenarios and the cost of a bin is proportional to its surface area. Our research shows that this problem is NP-hard. Based on previous research on 3D BPP, the surface area is determined by the sequence, spatial locations and orientations of items. Among these factors, the sequence of items plays a key role in minimizing the surface area. Inspired by recent achievements of deep reinforcement learning (DRL) techniques, especially Pointer Network, on combinatorial optimization problems such as TSP, a DRL-based method is applied to optimize the sequence of items to be packed into the bin. Numerical results show that the method proposed in this paper achieve about 5% improvement than heuristic method., Comment: 7 pages, 1 figures

In this study we proposed a device composed of dry electrode and dry adhesive medical patch for biopotentials measurement. The behavior of the dry adhesive with mushroom-shaped micropillars is characterized through normal and friction force test. The adhesion strength (~1.2 N/cm2) is comparable to acrylic medical patch, and the repeating cycle testing result demonstrates that the adhesion strength of dry adhesive medical patch is larger than that of acrylic medical patch. Moreover, the dry adhesive medical patch does not cause skin to turn allergic owning to its biocompatibility. The proposed device also is used to record electrocardiogram (ECG) with dry electrode. Compared with conventional wet electrode, the signal quality is outstanding. The QRS-complex and T-wave of ECG are clearly legible.

The retention and drainage of water on heat exchangers is extremely important in air-conditioning, refrigeration, and heat-pumping systems. In this work, droplets of varying sizes sliding on an inclined heat exchanger materials with and without a wettability gradient are observed using a high-speed camera. The dynamic contact angles, the shape evolution and the velocity of the droplet are obtained by image processing. Aluminum and copper surfaces are examined and the gradient is created by partially treating the base surface. The hypothesis is that the momentum of a sliding droplet on a treated surface will push the droplet onto the part without any treatment, so that water retention and drainage can be improved with limited surface treatment. It is found that the dynamic contact angle, the shape evolution and the velocity can be very different for droplets sliding in a wettability-increasing direction when compared to those sliding in a wettability-decreasing direction. The results are very important for the design of specialized heat transfer surfaces operating under dehumidification or defrosting conditions.

In this paper, a novel flexible dry electrode for long-term electroencephalogram (EEG) measurement is presented. Though the standard wet electrodes (Ag/AgCl) were used widely, they have their own drawbacks, such as the need for conductive gel and skin preparation, which causes the user discomfort and is unsafe, and cannot fit the long-term EEG measurement. To overcome these drawbacks of the wet electrodes, a novel flexible dry electrode made of Polydimethysiloxane is proposed; it works without conductive gel and skin preparation. More importantly, this flexible dry electrode with pins structure can directly measure the EEG of hairy sites through hair. The impedances in frequency and time domains are tested to characterize the performance of the proposed dry electrode. In addition, to estimate signal quality, the average correlation and the power spectrum are presented between different electrodes. This flexible dry electrode can meet the requirement of high quality EEG measurement.

The microelectromechanical systems process including cutting, isotropic wet-etching and sputtering was used to fabricate a pyramid micro-needle electrode, which could be applied in long-term electroencephalogram (EEG) measurement. A penetrating testing and comfort survey was presented to optimize the parameters of applying force and penetrating depth in order to make user comfort, safe and free of pain and bleeding. To investigate the performance of the micro-needle electrode, three micro-needle electrodes with different arrays were deployed to perform skin–electrode contact impedance experiments. Moreover, the impedances in time domain were measured to verify the feasibility of long time measurement. At last, EEG signals were recorded directly by three pairs of standard wet/micro-needle electrodes and the power spectrum density (PSD) was presented between standard wet electrode and micro-needle electrode to estimate signal quality. Based on the results of EEG signals and the PSD, the micro-needle electrode can be as a biopotential electrode for recording EEG with low skin–electrode contact impedance.

This paper investigates heat transfer and flow of U-shaped cooling passage with ribs in gas turbine blade by numerical methods. The Reynolds number ranges from 10000 to 40000, and there are three cooling passages with aspect ratio of 0.5, 1, 2, then the study conducts comparative analysis for a variety of programs in case of rotating. The results show that, ribs improve cooling performance of U-shaped passage significantly while obviously increase coolant flow loss. Heat transfer capability of passage wall is proportional to Reynolds number, but overall flow loss remain basically unchanged. Rotation improve first passage heat transfer clearly by Coriolis force while there is little effect on second passage, and it does not affect overall flow loss of U-shaped cooling passage.

The regulation of stomata, pores on the epidermis of leaves that allow for gas exchange, is an ideal target for creating a plant capable of acclimating to environmental stresses such as drought. Changes in stomatal density (SD) are correlated with different environments, but the identity of genes that act as modulators of SD are mostly unknown. To identify transcription factors that may act as modulators of SD, T-DNA mutants of candidate transcription factors identified in a genome-wide association study were characterized, and one candidate mutant displaying a phenotype was further characterized for anatomical and physiological traits. Expression of Arabidopsis thaliana plants with a mutation in the candidate gene had ~20% lower SD than their respective wild type lines, which was also correlated with a significantly lower transpiration rate. Expression of the candidate gene varied among alleles. Growth was not affected by any of the allelic mutations. Expression was repressed in response to water stress, suggesting that it may play a role in plant response to environmental stress. We have identified a potential modulator of acclimation through changes in epidermal development. Next steps include the identification of target genes and regulators.

In order to solve the parking problems in the metropolises, a new approach integrating active pattern for parking guidance information system composed of parks, cars and parking information service center and trafficmanagement center is proposed. A multi-phase navigation method based on a two-layer traffic map is employed for parking routes negotiation and guidance. The system is implemented based on an extended FIPA architecture through using mobile agent, message queue, agent container and agent execution environment, making full use of the interoperability of FIPA standards and the flexibility of mobile agent. The whole service environment can automatically execute park searching, parking price negotiation, parking space booking and parking routes negotiation and guidance using the intelligence, adaptability and collaboration of agents.

In order to provide the drivers a better parking guidance service, a multi-agent approach for parking negotiation and guidance is proposed in this paper. Based on distributed control theory, a city is divided into a number of districts each of which is equipped with a Parking Information Service Center (PISC). A distributed Multi-phase method based on a two-layer traffic map is employed for parking routes navigation. Besides, a route negotiation algorithm is also proposed in this paper. The agents thus can work cooperatively to execute the parking routes guidance without the intervention of drivers and parks.

In metropolises, parking fees vary widely and change dynamically in different periods of time and may not always match the drivers' expectation price. In order to provide the consumers a bargaining platform, an intelligent parking negotiation and guidance system is proposed through integrating the mobile agent with multi-agent system. The use of mobile agent allows the dynamic, stable and fast negotiation between cars and parks. Mobility can reduce negotiation time and data transmission over the wireless network. A negotiation algorithm based on human's bargaining process is also proposed in this paper. Simulation shows that the predetermined negotiation time can greatly influence the negotiation times.

A thin and flexible capacitive electrode for recording an electrocardiogram (ECG) signal has been developed. Compared with the conventional wet electrode, the capacitive electrode can work without conductive gel and skin preparation, and serves as a tool of long-term ECG measurement. The designed electrode consists of a sensing plate, an active shield plate and two insulating layers, which is fabricated by the micro-electro-mechanical system process. The test result shows that the capacitive electrode can obtain a high-quality ECG signal that is comparable to the one recorded by the conventional wet electrode. The capacitive electrode can be arbitrarily bent to fit the human torso because of its extremely thin and flexible feature. Moreover, a simple front-end circuit is used to integrate more easily into the measurement system.