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Recent mechanistic studies have indicated that combinations of radiotherapy (RT) plus immunotherapy (via CSF-1R inhibition) can serve as a strategy to overcome RT resistance and improve the survival of glioma mice. Given the high mortality rate for glioma, including low-grade glioma (LGG) patients, it is of critical importance to investigate the mechanism of the combination of RT and immunotherapy and further translate the mechanism from mouse studies to improve survival of RT-treated human glioma patients. Using the RNA-seq data from a glioma mouse study, 874 differentially expressed genes (DEGs) between the group of RT-treated mice at glioma recurrence and the group of mice with combination treatment (RT plus CSF-1R inhibition) were translated to the human genome to identify significant molecular pathways using the KEGG enrichment analysis. The enrichment analysis yields statistically significant signaling pathways, including the phosphoinositide 3-kinase (PI3K)/AKT pathway, Hippo pathway, and Notch pathway. Within each pathway, a candidate gene set was selected by Cox regression models as genetic biomarkers for resistance to RT and response to the combination of RT plus immunotherapies. Each Cox model is trained using a cohort of 295 RT-treated LGG patients from The Cancer Genome Atlas (TCGA) database and validated using a cohort of 127 RT-treated LGG patients from the Chinese Glioma Genome Atlas (CGGA) database. A four-DEG signature (ITGB8, COL9A3, TGFB2, JAG1) was identified from the significant genes within the three pathways and yielded the area under time-dependent ROC curve AUC = 0.86 for 5-year survival in the validation set, which indicates that the selected DEGs have strong prognostic value and are potential intervention targets for combination therapies. These findings may facilitate future trial designs for developing combination therapies for glioma patients.

Nitrogen and sulfur co-doped graphene-like carbon nanosheets (CNSs) with a two-dimensional structure are prepared by using methylene blue as a carbon source and expanded vermiculite as a template. After static negative pressure adsorption, high-temperature calcination, and etching in a vacuum oven, they are embedded in the limited space of the vermiculite template. The addition of an appropriate number of mixed elements can improve the performance of a battery. Via scanning electron microscopy, it is found that the prepared nitrogen–sulfur-co-doped carbon nanosheets exhibit a thin yarn shape. The XPS results show that there are four elements of C, N, O, and S in the carbon materials (CNS-600, CNS-700, CNS-800, CNS-900) prepared at different temperatures, and the N atom content shows a gradually decreasing trend. It is mainly doped into a graphene-like network in four ways (graphite nitrogen, pyridine nitrogen, pyrrole nitrogen, and pyridine nitrogen oxide), while the S element shows an increasing trend, mainly in the form of thiophene S and sulfur, which is covalently linked to oxygen. The results show that CNS-700 has a discharge-specific capacity of 460 mAh/g at a current density of 0.1 A/g, and it can still maintain a specific capacity of 200 mAh/g at a current density of 2 A/g. The assembled lithium-ion capacitor has excellent energy density and power density, with a maximum power density of 20,000 W/kg.

The electrocatalytic conversion of biomass into high-value-added chemicals is one of the effective methods of green chemistry. Conventional metal catalysts have disadvantages, such as low atomic utilization and small surface areas. Catalyst materials derived from metal–organic frameworks (MOFs) have received much attention due to their unique physicochemical properties. Here, an MOF-derived non-precious metal CoxNiyS electrocatalyst was applied to the oxidation of biomass-derivative 5-hydroxymethylfurfural (HMF). The HMF oxidation reaction activities were modulated by regulating the content of Co and Ni bimetals, showing a volcano curve with an increasing proportion of Co. When the Co:Ni ratio was 2:1, the HMF conversion rate reached 84.5%, and the yield of the main product, 2,5-furandicarboxylic acid (FDCA), was 54%. The XPS results showed that the presence of high-valent nickel species after electrolysis, which further proved the existence and reactivity of NiOOH, as well as the synergistic effect of Co and Ni promoted the conversion of HMF. Increasing the content of Ni could increase the activity of HMF electrochemical oxidation, and increasing the content of Co could reduce the increase in the anodic current. This study has important significance for designing better HMF electrochemical catalysts in the future.

The spatial distribution pattern of urban spatial structure affects air flow and local meteorological conditions, which in turn influence the diffusion of air pollutants. This study built the urban spatial structure index system based on DEM, urban road networks, and big data. The ordinary kriging interpolation method was used to analyze the spatial distribution of gaseous pollutant concentrations in Jinan City. Correlation analysis, stepwise regression analysis, and bivariate global spatial autocorrelation analysis were used to study the influence of the urban spatial structure index on the spatial distribution of gaseous pollutant concentration. The main conclusions were as follows: (1) Evident spatial and temporal differences were observed in the concentration distribution of gaseous pollutants in Jinan. The spatial distribution of NO2 and CO concentrations showed a gradual decrease from north to south. Spatial heterogeneity was observed in the distribution of SO2 and O3 concentrations. (2) The urban spatial structure indicators had varying effects on the spatial distribution of different gaseous pollutant concentrations. The important factors that influenced the spatial distribution of urban gaseous pollutant concentrations included terrain elevation, building density, building volume, and floor area ratio. The greater the terrain undulation, the denser the building distribution, the greater the difference in building volume, and the greater the plot ratio, the greater the impact on the diffusion and spatial distribution of urban gaseous pollutants. (3) The spatial distribution of urban gaseous pollutant concentrations was significantly affected by the urban spatial structure indicators in the surrounding areas. Furthermore, the spatial distributions of NO2, SO2, CO, and O3 concentrations had a significant negative spatial correlation with the average DEM and standard deviation of the surrounding adjacent areas and a significant positive spatial correlation with the average and standard deviation of building height, standard deviation of building area, and building density in the surrounding adjacent areas (in June).

The permanent magnet synchronous motor (PMSM) has been widely used in the field of ship electric propulsion due to its advantages of a small size, light weight, low loss, and high efficiency. In this paper, a 100 kW ship-side thruster motor was taken as the research object, and the problem of the high harmonic content of the air gap magnetic flux density in the motor was addressed by designing a rotor eccentricity. On this basis, the hybrid Taguchi method of genetic algorithm was used to optimize the rotor structural parameters with increasing the efficiency and reducting the cost of the motor as the optimization objectives. The results show that the performance and economy of the motor have been greatly improved after optimization. Finally, the motor weight reduction hole was designed, and a prototype was manufactured and tested. The test data are within the allowable range compared with the simulation data, verifying the effectiveness of the multiobjective optimization algorithm proposed in this paper.

In order to explore the fracture law and structural evolution characteristics of overlying strata in deep high-stress mining, according to the geometric characteristics and mechanical causes of overlying strata in different mining stages of the stope, four stages of overlying strata structure model are established and analyzed in turn. According to the characteristics of the overburden load transfer path in the deep high-stress stope, the fracture law and macroscopic mechanical response of overburden are analyzed by MATLAB and PFC2D numerical simulation method. The evolution model of overburden structure and load transfer in ‘four stages and three modes’ of the deep high-stress stope is constructed, and the stage fracture effect of ‘beam, plate and arch’ is put forward. The results show that the overburden rock is a fixed beam structure before the initial weighting. After the initial weighting, it evolves into a plate structure with three sides fixed and one side simply supported. After the periodic weighting, the overburden rock structure further evolves into a plate structure with one side fixed and three sides simply supported. After full mining, the overburden rock forms an arch structure, and the load is transmitted by the beam–plate–arch path. The findings of the study provide an important basis for exploring the nature of overburden transport and load transfer in deep high-stress quarries and strengthening overburden prevention and control.

The growing need for deep-sea biological research and environmental monitoring has expanded the demand for benthic landers. Compared with remotely operated vehicles (ROVs) and autonomous underwater vehicles (AUVs), benthic landers can reduce overall operation cost and also possess longer endurance. Configuring a suitable descent velocity is important for benthic lander designs, helping them avoid retrieval failure and improve sea trial efficiencies. In this study, an effective scheme for the configuration and optimization of a self-developed benthic lander was outlined. First, the structural characteristics of the benthic lander were analyzed, and then a dynamic model was established. Second, the hydrodynamic coefficients of the benthic lander during its descent process were calculated using computational fluid dynamics (CFD) methods. Third, the MATLAB Simulink simulation environment was used to solve the dynamic model, and then the multi-objective optimization algorithm was introduced for the optimization design. Finally, the model was validated based on sea trial data, which demonstrated that the designed configuration and optimization scheme were correct and efficient. Collectively, this work provides a useful reference for the rational configuration and practical application of benthic landers.

This paper proposes a fully analytical loss model to reduce circling currents and improve the power efficiency of a class Φ2 inverter. Firstly, analytical expression of the switching node voltage is derived by analyzing its harmonic components. Based on the result, the power switch is modeled as a voltage source, where the circuit is simplified to a linear network and analytical expressions of branch currents are solved. Secondly, root mean square (RMS) values of branch currents and component losses are calculated to form the analytical loss model for a Φ2 inverter. The influence of circuit parameters on the circling current and power efficiency are thoroughly analyzed, which derives optimal design constraints to reduce circling currents of a class Φ2 inverter. Furthermore, detailed design guidance and equations are provided to calculate circuit parameters of a class Φ2 inverter, which reduces its circling currents and improves overall power efficiency. Finally, a class Φ2 inverter prototype is built, and experimental results demonstrate a 7% efficiency improvement compared to conventional empirical design methods.

A high-fat diet plays an important role in aggravating cancers. Palmitic acid (PA) is one of the components of saturated fatty acids; it has been reported to promote tumor proliferation in melanomas, but the signal transduction pathway mediated by palmitic acid remains unclear. This study showed that palmitic acid can promote the lung metastasis of melanomas. Moreover, the interaction between palmitic acid and toll-like receptor 4 (TLR4) was predicted by molecular docking. The experimental results proved that palmitic acid could promote the TLR4 and Toll/IL-1 receptor domain-containing adaptor-inducing IFN-β (TRIF) expression. The expression of Pellino1 (Peli1) and the phosphorylation of NF-kappa B (pNF-κB) were downregulated after the suppression of TLR4 and the silencing of Peli1 also inhibited the phosphorylation of NF-κB. Therefore, we concluded that palmitic acid promoted the lung metastasis of melanomas through the TLR4/TRIF-Peli1-pNF-κB pathway.

Addressing the shortcomings of existing low-frequency oscillation research on electrified railways, which has mainly focused on single-type trains and lacks the accurate modeling of traction inverter systems, in this paper we modeled and analyzed low-frequency oscillations in an electrified railway passenger and freight mixed-operation vehicle–grid system. First, an equivalent model of the DC side of the traction inverter was established, with the inverter system being equivalent to the parallel connection of the load resistance and the current source, and the specific mathematical expression was determined and verified by impedance measurement. Secondly, based on the equivalent model of the DC side of the traction inverter, a small signal model of the vehicle–grid system under the mixed operating conditions of CRH5 and HXD2B considering the inverter system was established. The generalized Nyqusit criterion was used to study the low-frequency oscillation characteristics under mixed transportation conditions. The accuracy of the established model and the correctness of the theoretical analysis were verified based on Matlab/Simulink. Finally, using the dominant pole theory to analyze the low-frequency stability conditions, the relationship between the number of mixed trains and the minimum short-circuit ratio was obtained, and the simulation verification was carried out.

This paper presents a triple-mode average current control (TACC) strategy to achieve unity power factor and reduce the current stress for a boost PFC converter. The controller switches among different modes in each half-line cycle, and smooth transition is ensured by mapping of the operation region. By adaptive mode shifting, it reduces the current stress and current distortion caused by non-linear effects. With valley current shaping and comparisons, the TACC controller accordingly incorporates three control laws to adapt different modes. In discontinuous conduction mode (DCM), a variable on-time is calculated while the modulation is equivalent to PWM. In critical conduction mode (CRM), a constant on-time is derived, while the switching cycle is modified to regulate the current average value. For both DCM and CRM, the switching cycle is slightly extended to realize valley switching. Furthermore, with valley current shaping, the proposed controller reuses the CRM calculation to form continuous conduction mode (CCM) control law. To make the control laws compatible, normalized mapping and design rules are provided with respect to mode boundaries. This allows the TACC controller to automatically switch among different modes. Finally, experimental results prove the effectiveness of the controller in reducing the current stress and enlarging the preferable power range.

In this experiment, a Sn35Bi0.3Ag–xIn (x = 0, 0.5, 1.0, 1.5) alloy solder was prepared by electromagnetic induction heating furnace. The effects of In on the thermodynamic properties, wettability, interface microstructure, and soldering performance of Sn35Bi0.3Ag–xIn/Cu solder joints were studied by a synchrotron thermal analyzer (DSC), contact-angle measuring instrument, scanning electron microscope (SEM), energy dispersive spectrometer (EDS), and universal tensile testing machine. The research showed that adding a small amount of In reduced the solid–liquid temperature and improved the wettability of the alloy solder. At the interface of SnBiAg–xIn/Cu joint, it was found that In atoms replaced part of Sn atoms, forming the Cu6 (Sn, In)5 phase and scallop-like Cu3 (Sn, In) phase. When adding 0.5% and 1.0% In elements, it was found that the Bi phase appeared on the solder side of the interface layer, which hindered the growth of the intermetallic compound (IMC) and reduced the thickness of the IMC layer. Among them, the thickness of the IMC layer of the SnBiAg–1.0In/Cu joint was the smallest, and the shear strength was the highest, which was 55.1 MPa. In addition, the fracture morphology of the solder joint was observed, and it was found that the fracture mode was brittle fracture, and the SnBiAg–xIn/Cu solder joint fractured from the IMC and solder side.

Traumatic brain injury (TBI) is a common neurological disease. Netrin-1 and deleted in colorectal cancer (DCC) receptor are potential biomarkers associated with nerve regeneration and immune regulation. We aimed to investigate the ability of the DCC receptor and Netrin-1 to predict a high ICP level after operation in severe traumatic brain injury and their prognostic significance. This study is a prospective observational study. We selected 23 patients with traumatic brain injury who had undergone surgical operations as subjects. Immunohistochemical staining was performed on the contusion tissue that was removed by the operation to determine the expression of DCC receptor. At the same time, enzyme-linked immunosorbent assay (ELISA) kits were used to detect the serum Netrin-1 content. Determination of intracranial pressure (ICP) value was measured by intraventricular catheter. The Glasgow Outcome Scale (GOS) score at six months after trauma was defined as the main study endpoint. The results showed that serum Netrin-1 concentrations of patients in the critical TBI group (GCS 3–5 points) was significantly lower than that in the severe TBI group (GCS 6–8 points). The ICP peak and average mannitol consumption in the high Netrin-1 group were significantly lower than those in the low Netrin-1 group. DCC receptor-positive patients had a significantly lower ICP peak. There was no significant difference in six month-GOS scores between patients in the high and low Netrin-1 groups, while DCC receptor concentrations below 3.82 ng/mL predicted poor prognosis (GOS 1–3 points). In conclusion, the expression level of the DCC receptor can better evaluate the postoperative high ICP level and prognosis than the level of serum Netrin-1 in severe traumatic brain injury.

In this study, the W (10–20%)–Cu composites were simultaneously fabricated using commercial, graded commercial, and graded jet-milled W powder. The results show that the W–Cu composites prepared with the graded jet-milled W powders have the highest density and best comprehensive performance due to the combined effect of the particle gradation and jet-milling treatment. Particle gradation is employed to increase the packing density of powders, thereby increasing the relative density of the compressed W skeleton, and the rounded powder with narrow particle size distribution after jet-milling treatment is used to reduce the enclosed pores formed during the process of compacting and infiltration. W–Cu composites with a high density of 16.25 g/cm3 can be directly obtained by conventional compacting at a low pressure of 300 MPa and following infiltration.

Antarctic geothermal heat flux is a basic input variable for ice sheet dynamics simulation. It greatly affects the temperature and mechanical properties at the bottom of the ice sheet, influencing sliding, melting, and internal deformation. Due to the fact that the Antarctica is covered by a thick ice sheet, direct measurements of heat flux are very limited. This study was carried out to estimate the regional heat flux in the Antarctic continent through geophysical inversion. Princess Elizabeth Land, East Antarctica is one of the areas in which we have a weak understanding of geothermal heat flux. Through the latest airborne geomagnetic data, we inverted the Curie depth, obtaining the heat flux of bedrock based on the one-dimensional steady-state heat conduction equation. The results indicated that the Curie depth of the Princess Elizabeth Land is shallower than previously estimated, and the heat flux is consequently higher. Thus, the contribution of subglacial heat flux to the melting at the bottom of the ice sheet is likely greater than previously expected in this region. It further provides research clues for the formation of the developed subglacial water system in Princess Elizabeth Land.

In this paper, we proposed a novel information-based approach to precision analysis of indoor wireless local area network (WLAN) localization using location fingerprint. First of all, by using the Fisher information matrix (FIM), we derive the fundamental limit of WLAN fingerprint-based localization precision considering different signal distributions in characterizing the variation of received signal strengths (RSSs) in the target environment. After that, we explore the relationship between the localization precision and access point (AP) placement, which can provide valuable suggestions for the design of the highly-precise localization system. Second, we adopt the heuristic simulated annealing (SA) algorithm to optimize the AP locations for the sake of approaching the fundamental limit of localization precision. Finally, the extensive simulations and experiments are conducted in both regular line-of-sight (LOS) and irregular non-line-of-sight (NLOS) environments to demonstrate that the proposed approach can not only effectively improve the WLAN fingerprint-based localization precision, but also reduce the time overhead.

Switched mode power converters are nonlinear systems, and it is a constant challenge to improve their modeling accuracy and control performance. In this paper, a State Switched Discrete-time Model (SSDM) is proposed, which achieves a higher accuracy at a high frequency than that of conventional state averaged models. Instead of averaging the converter states for approximation, the states within each switching cycle are considered in the modeling. Based on total differential equations of switching-ON and switching-OFF durations, the inductor current and output voltage within a cycle are accurately calculated, which derives the SSDM. Furthermore, a Digital Predictive Voltage Programmed (DPVP) control strategy is derived through the SSDM. Through voltage prediction, a suitable duty ratio is calculated that regulates the output voltage to its reference value in the minimum switching cycles. In this way, the converter achieves a very fast load/line transient response and reference tracking speed, and it exhibits a high stability under deviated inductance. Finally, the accuracy of SSDM and the system stability are proved by frequency response analyses and experiments.

Advances in cancer treatment have led to significant improvements in long-term survival in many types of cancer, but heart dysfunction and heart failure, associated with cancer treatment, have also increased. Anthracyclines are the main cause of this type of cardiotoxicity. In this study, we describe a combined experimental and cell morphology analysis approach for the high-throughput measurement and analysis of a cardiomyocyte cell profile, using partial least square linear discriminant analysis (PLS-LDA) as the pattern recognition algorithm. When screening a small-scale natural compound library, rosmarinic acid (RosA), as a candidate drug, showed the same cardioprotective effect as the positive control. We investigated the protective mechanism of RosA on a human cardiomyocyte cell line (AC16) and human induced pluripotent stem-cell-derived cardiomyocytes (hiPSC-CMs). We showed that RosA pretreatment suppressed doxorubicin (Dox)-induced cell apoptosis and decreased the activity of caspase-9. RosA promotes the expression of Heme oxygenase-1 (HO-1) and reduces the production of reactive oxygen species (Ros), which is induced by Dox. Meanwhile, it can also promote the expression of cardiac-development-related protein, including histone deacetylase 1 (HDAC1), GATA binding protein 4 (GATA4) and troponin I3, cardiac type (CTnI). Collectively, our data support the notion that RosA is a protective agent in hiPSC-CMs and has the potential for therapeutic use in the treatment of cancer therapy-related cardiac dysfunction and heart failure.

Temporal associations in longitudinal nontargeted metabolomics data are generally ignored by common pattern recognition methods such as partial least squares discriminant analysis (PLS-DA) and orthogonal partial least squares discriminant analysis (OPLS-DA). To discover temporal patterns in longitudinal metabolomics, a multitask learning (MTL) method employing structural regularization was proposed. The group regularization term of the proposed MTL method enables the selection of a small number of tentative biomarkers while maintaining high prediction accuracy. Meanwhile, the nuclear norm imposed into the regression coefficient accounts for the interrelationship of the metabolomics data obtained on consecutive time points. The effectiveness of the proposed method was demonstrated by comparison study performed on a metabolomics dataset and a simulating dataset. The results showed that a compact set of tentative biomarkers charactering the whole antipyretic process of Qingkailing injection were selected with the proposed method. In addition, the nuclear norm introduced in the new method could help the group norm to improve the method’s recovery ability.

The dried roots of Euphorbia kansui S.L.Liou ex S.B.Ho have long been used to treat edema in China. However, the severe toxicity caused by Euphorbia kansui (EK) has seriously restricted its clinical application. Although EK was processed with vinegar to reduce its toxicity, the detailed mechanisms of attenuation in toxicity of EK stir-fried with vinegar (VEK) have not been well delineated. Diterpenoids are the main toxic ingredients of EK, and changes in these after processing may be the underlying mechanism of toxicity attenuation of VEK. 3-O-(2′E,4′Z-decadienoyl)-20-O-acetylingenol (3-O-EZ) is one of the diterpenoids derived from EK, and the content of 3-O-EZ was significantly reduced after processing. This study aims to explore the underlying mechanisms of toxicity reduction of VEK based on the change of 3-O-EZ after processing with vinegar. Based on the chemical structure of 3-O-EZ and the method of processing with vinegar, simulation experiments were carried out to confirm the presence of the product both in EK and VEK and to enrich the product. Then, the difference of peak area of 3-O-EZ and its hydrolysate in EK and VEK were detected by ultra-high-performance liquid chromatography (UPLC). Furthermore, the toxicity effect of 3-O-EZ and its hydrolysate, as well as the underlying mechanism, on zebrafish embryos were investigated. The findings showed that the diterpenoids (3-O-EZ) in EK can convert into less toxic ingenol in VEK after processing with vinegar; meanwhile, the content of ingenol in VEK was higher than that of EK. More interestingly, the ingenol exhibited less toxicity (acute toxicity, developmental toxicity and organic toxicity) than that of 3-O-EZ, and 3-O-EZ could increase malondialdehyde (MDA) content and reduce glutathione (GSH) content; cause embryo oxidative damage by inhibition of the succinate dehydrogenase (SDH) and superoxide dismutase (SOD) activity; and induce inflammation and apoptosis by elevation of IL-2 and IL-8 contents and activation of the caspase-3 and caspase-9 activity. Thus, this study contributes to our understanding of the mechanism of attenuation in toxicity of VEK, and provides the possibility of safe and rational use of EK in clinics.

Due to the wide deployment of wireless local area networks (WLAN), received signal strength (RSS)-based indoor WLAN localization has attracted considerable attention in both academia and industry. In this paper, we propose a novel page rank-based indoor mapping and localization (PRIMAL) by using the gene-sequenced unlabeled WLAN RSS for simultaneous localization and mapping (SLAM). Specifically, first of all, based on the observation of the motion patterns of the people in the target environment, we use the Allen logic to construct the mobility graph to characterize the connectivity among different areas of interest. Second, the concept of gene sequencing is utilized to assemble the sporadically-collected RSS sequences into a signal graph based on the transition relations among different RSS sequences. Third, we apply the graph drawing approach to exhibit both the mobility graph and signal graph in a more readable manner. Finally, the page rank (PR) algorithm is proposed to construct the mapping from the signal graph into the mobility graph. The experimental results show that the proposed approach achieves satisfactory localization accuracy and meanwhile avoids the intensive time and labor cost involved in the conventional location fingerprinting-based indoor WLAN localization.

Model performance of the partial least squares method (PLS) alone and bagging-PLS was investigated in online near-infrared (NIR) sensor monitoring of pilot-scale extraction process in Fructus aurantii. High-performance liquid chromatography (HPLC) was used as a reference method to identify the active pharmaceutical ingredients: naringin, hesperidin and neohesperidin. Several preprocessing methods and synergy interval partial least squares (SiPLS) and moving window partial least squares (MWPLS) variable selection methods were compared. Single quantification models (PLS) and ensemble methods combined with partial least squares (bagging-PLS) were developed for quantitative analysis of naringin, hesperidin and neohesperidin. SiPLS was compared to SiPLS combined with bagging-PLS. Final results showed the root mean square error of prediction (RMSEP) of bagging-PLS to be lower than that of PLS regression alone. For this reason, an ensemble method of online NIR sensor is here proposed as a means of monitoring the pilot-scale extraction process in Fructus aurantii, which may also constitute a suitable strategy for online NIR monitoring of CHM.

To realize accurate current control for a boost converter, a precise measurement of the inductor current is required to achieve high resolution current regulating. Current sensors are widely used to measure the inductor current. However, the current sensors and their processing circuits significantly contribute extra hardware cost, delay and noise to the system. They can also harm the system reliability. Therefore, current sensorless control techniques can bring cost effective and reliable solutions for various boost converter applications. According to the derived accurate model, which contains a number of parasitics, the boost converter is a nonlinear system. An Extended Kalman Filter (EKF) is proposed for inductor current estimation and output voltage filtering. With this approach, the system can have the same advantages as sensored current control mode. To implement EKF, the load value is necessary. However, the load may vary from time to time. This can lead to errors of current estimation and filtered output voltage. To solve this issue, a load variation elimination effect elimination (LVEE) module is added. In addition, a predictive average current controller is used to regulate the current. Compared with conventional voltage controlled system, the transient response is greatly improved since it only takes two switching cycles for the current to reach its reference. Finally, experimental results are presented to verify the stable operation and output tracking capability for large-signal transients of the proposed algorithm.

Laser-induced breakdown spectroscopy (LIBS) was applied to perform a rapid elemental analysis and provenance study of Blumea balsamifera DC. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were implemented to exploit the multivariate nature of the LIBS data. Scores and loadings of computed principal components visually illustrated the differing spectral data. The PLS-DA algorithm showed good classification performance. The PLS-DA model using complete spectra as input variables had similar discrimination performance to using selected spectral lines as input variables. The down-selection of spectral lines was specifically focused on the major elements of B. balsamifera samples. Results indicated that LIBS could be used to rapidly analyze elements and to perform provenance study of B. balsamifera.

In digital current mode controlled DC-DC converters, conventional current sensors might not provide isolation at a minimized price, power loss and size. Therefore, a current observer which can be realized based on the digital circuit itself, is a possible substitute. However, the observed current may diverge due to the parasitic resistors and the forward conduction voltage of the diode. Moreover, the divergence of the observed current will cause steady state errors in the output voltage. In this paper, an optimal current observer is proposed. It achieves the highest observation accuracy by compensating for all the known parasitic parameters. By employing the optimal current observer-based predictive current controller, a buck converter is implemented. The converter has a convergently and accurately observed inductor current, and shows preferable transient response than the conventional voltage mode controlled converter. Besides, costs, power loss and size are minimized since the strategy requires no additional hardware for current sensing. The effectiveness of the proposed optimal current observer is demonstrated experimentally.

Oxidative stress is the main pathogenesis of diabetic microangiopathy, which can cause microvascular endothelial cell damage and destroy vascular barrier. In this study, it is found that carnosol protects human microvascular endothelial cells (HMVEC) through antioxidative mechanisms. First, we measured the antioxidant activity of carnosol. We showed that carnosol pretreatment suppressed tert-butyl hydroperoxide (t-BHP)-induced cell viability, affected the production of lactate dehydrogenase (LDH) as well as reactive oxygen species (ROS), and increased the produce of nitric oxide (NO). Additionally, carnosol promotes the protein expression of vascular endothelial cadherin (VE-cadherin) to keep the integrity of intercellular junctions, which indicated that it protected microvascular barrier in oxidative stress. Meanwhile, we investigated that carnosol can interrupt Nrf2-Keap1 protein−protein interaction and stimulated antioxidant-responsive element (ARE)-driven luciferase activity in vitro. Mechanistically, we showed that carnosol promotes the expression of heme oxygenase 1(HO-1) and nuclear factor-erythroid 2 related factor 2(Nrf2). It can also promote the expression of endothelial nitric oxide synthase (eNOS). Collectively, our data support the notion that carnosol is a protective agent in HMVECs and has the potential for therapeutic use in the treatments of microvascular endothelial cell injury.

Euphorbia kansui stir-fried with vinegar (V-kansui) has promising biological activities toward treating malignant ascites with reduced toxicity compared to crude kansui. But the mechanism concerning promoting the excretion of ascites has not been systematically studied. The purpose of this paper was to investigate the possible mechanism of V-kansui in treating malignant ascites, including metabolic pathways and molecular mechanism using an integrated serum and urine metabolomics coupled with network pharmacology. Serum and urine samples of rats were collected and analyzed by ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS). A comparison with crude kansui was also made to demonstrate the feasibility of processing. Principle component analysis (PCA) and orthogonal partial least square discriminate analysis (OPLS-DA) were conducted to discriminate the groups, search important variables and reveal the possible pathways. A compound-target-metabolite network was finally constructed to identify the crucial targets to further understand the molecular mechanism. Sixteen significant metabolites contributing to the discrimination of model and control groups were tentatively screened out. They were mainly involved in the arachidonic acid metabolism, steroid hormone biosynthesis and primary bile acid to possibly reduce inflammatory and modulate the renin-angiotensin-aldosterone system to achieve treating malignant ascites. A bio-network starting from the compounds and ending in the metabolites was constructed to elucidate the molecular mechanism. HSP90AA1, ANXA2, PRDX6, PCNA, SOD2 and ALB were identified as the potential key targets that were responsible for the treatment of malignant ascites by the parameter combining the average shortest path length and betweenness centrality. The correlated 17 compounds were considered as the potential active ingredients in V-kansui. In addition, the metabolomics showed that the effect of V-kansui was almost in accordance with crude kansui. These results systematically revealed the mechanism of V-kansui against malignant ascites for the first time using metabolomics coupled with network pharmacology. V-kansui could be a promising safe and therapeutic medicine for the excretion of ascites.

In servo systems, encoders are usually used to measure the position and speed signals of electric machines. But in a low speed range, the traditional M/T method has a larger time delay, which will cause an increase of the speed loop order and degradation of the speed loop performance. A method employed to reduce the delay of speed feedback by using a reduced-order Extended Kalman Filter (EKF) is introduced in this paper. The speed of the permanent magnet synchronous motor is estimated by the reduced-order EKF in a low speed range, which reduces the delay of speed feedback and extends the cutoff frequency of the speed loop to improve the dynamic performance of the servo system. In order to solve the issues that the traditional full-order EKF is sensitive to the inertia of the system and computationally complex, a composite load torque observer (CLTO) is proposed in this paper. The load torque and the friction torque are simultaneously observed by the CLTO. Additionally, the CLTO is used to reduce the order of the EKF, which reduces the sensitivity of EKF on inertia to enhance the robustness of the algorithm and simplifies the computational complexity. The feasibility and effectivity of the above method are verified by simulations and experiments.

Layered double hydroxide (LDH) is a layered solid containing positively charged layers with negatively charged anions as an interchangeable interlayer. In this research, Mg(Al)O supports were synthesized with three different Mg:Al molar ratios, and bimetallic PtSn catalysts were loaded onto the supports via the anion exchange method. The properties of ethane dehydrogenation of the PtSn/Mg(Al)O catalysts were investigated. The results show that the structure and properties of the PtSn/Mg(Al)O catalysts were influenced by the Mg:Al molar ratio of the hydrotalcites, which consequently influenced the ethane dehydrogenation performance. When the Mg:Al ratio was 5:1, the ethane dehydrogenation performance was optimal, relative to the Mg:Al ratios of 2:1 and 10:1.

In this research, a new triterpenoid, tirucalla-8,24-diene-3β,11β-diol-7-one (1), and eupha-8,24-diene-3β,11β-diol-7-one (2), which was isolated from Euphorbia kansui for the first time, together with twelve other known compounds (3–14), were isolated from the ethyl acetate extract of Euphorbia kansui. Their structures were elucidated based on High resolution electrospray ionization mass spectrometry (HR-ESI-MS), Infrared Spectroscopy (IR), 1D and 2D Nuclear Magnetic Resonance (NMR) data. Both constituents 1 and 2 exhibited moderate cytotoxicity against colon cancer HCT-116, gastric cancer MKN-45 and breast cancer MCF-7.

Location estimation plays a crucial role in Location-Based Services (LBSs) with satisfactory user experience. The Wireless Local Area Network (WLAN) localization approach is preferred as a cost-efficient solution to indoor localization on account of the widely-deployed WLAN infrastructures. In this paper, we propose a new WLAN Received Signal Strength (RSS)-based indoor localization approach using the semi-supervised manifold alignment with dimension expansion. In concrete terms, we first construct an innovative objective function based on the augmented physical coordinates and the corresponding WLAN RSS measurements. Second, the closed-form solution to the objective function is derived out according to the Lagrange multiplier equation, which results in the manifold in physical coordinate space. Third, the target location is estimated by matching the transformed newly-collected RSS against the manifold. The localization performance with noise perturbation is analyzed upon the constructed objective function, and meanwhile, the closed-form solution to the objective function with respect to multiple types of measurements is also derived out for the sake of leveraging all of the potential measurements for indoor localization. The extensive testing results show that the proposed approach performs well in localization accuracy even at low calibration load, and its performance can be further improved by using multiple types of measurements for localization.

Endothelin-1 (ET-1) autocrine and paracrine signaling modulate cell proliferation of tumor cells by activating its receptors, endothelin A receptor (ETAR) and endothelin B receptor (ETBR). Dysregulation of ETAR activation promotes tumor development and progression. The potential of ETAR antagonists and the dual-ETAR and ETBR antagonists as therapeutic approaches are under preclinical and clinical studies. Salvianolic acid A (Sal A) is a hydrophilic polyphenolic derivative isolated from Salvia miltiorrhiza Bunge (Danshen), which has been reported as an anti-cancer and cardio-protective herbal medicine. In this study, we demonstrate that Sal A inhibits ETAR activation induced by ET-1 in both recombinant and endogenous ETAR expression cell lines. The IC50 values were determined as 5.7 µM in the HEK293/ETAR cell line and 3.14 µM in HeLa cells, respectively. Furthermore, our results showed that Sal A suppressed cell proliferation and extended the doubling times of multiple cancer cells, including HeLa, DU145, H1975, and A549 cell lines. In addition, Sal A inhibited proliferation of DU145 cell lines stimulated by exogenous ET-1 treatment. Moreover, the cytotoxicity and cardio-toxicity of Sal A were assessed in human umbilical vein endothelial cells (HUVEC) and Human-induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs), which proved that Sal A demonstrates no cytotoxicity or cardiotoxicity. Collectively, our findings indicate that Sal A is a novel anti-cancer candidate through targeting ETAR.

Since driving cycle greatly affects load power demand, driving cycle identification (DCI) is proposed to predict power demand that can be expected to prepare for the power distribution between battery and supercapacitor. The DCI is developed based on a learning vector quantization (LVQ) neural network method, which is assessed in both training and validation based on the statistical data obtained from six standard driving cycles. In order to ensure network accuracy, characteristic parameter and slide time window, which are two important factors ensuring the network accuracy for onboard hybrid energy storage system (HESS) applications in electric vehicles, are discussed and designed. Based on the identification results, Multi-level Haar wavelet transform (Haar-WT) is proposed for allocating the high frequency components of power demand into the supercapacitor which could damage battery lifetime and the corresponding low frequency components into the battery system. The proposed energy management system can better increase system efficiency and battery lifetime compared with the conventional sole frequency control. The advantages are demonstrated based on a randomly generated driving cycle from the standard driving cycle library via simulation.

Due to drug-induced potential congestive heart failure and irreversible dilated cardiomyopathies, preclinical evaluation of cardiac dysfunction is important to assess the safety of traditional or novel treatments. The embryos of Nelumbo nucifera Gaertner seeds are a homology of traditional Chinese medicine and food. In this study, we applied the real time cellular analysis (RTCA) Cardio system, which can real-time monitor the contractility of cardiomyocytes (CMs), to evaluate drug safety in rat neonatal CMs and human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs). This study showed detailed biomechanical CM contractility in vitro, and provided insights into the cardiac dysfunctions associated with liensinine and neferine treatment. These effects exhibited dose and time-dependent recovery. Neferine showed stronger blocking effect in rat neonatal CMs than liensinine. In addition, the effects of liensinine and neferine were further evaluated on hiPS-CMs. Our study also indicated that both liensinine and neferine can cause disruption of calcium homeostasis. For the first time, we demonstrated the potential cardiac side effects of liensinine or neferine. While the same inhibition was observed on hiPS-CMs, more importantly, this study introduced an efficient and effective approach to evaluate the cardiotoxicity of the existing and novel drug candidates.

To accurately, safely, and efficiently evaluate the bitterness of Traditional Chinese Medicines (TCMs), a robust predictor was developed using robust partial least squares (RPLS) regression method based on data obtained from an electronic tongue (e-tongue) system. The data quality was verified by the Grubb’s test. Moreover, potential outliers were detected based on both the standardized residual and score distance calculated for each sample. The performance of RPLS on the dataset before and after outlier detection was compared to other state-of-the-art methods including multivariate linear regression, least squares support vector machine, and the plain partial least squares regression. Both R2 and root-mean-squares error (RMSE) of cross-validation (CV) were recorded for each model. With four latent variables, a robust RMSECV value of 0.3916 with bitterness values ranging from 0.63 to 4.78 were obtained for the RPLS model that was constructed based on the dataset including outliers. Meanwhile, the RMSECV, which was calculated using the models constructed by other methods, was larger than that of the RPLS model. After six outliers were excluded, the performance of all benchmark methods markedly improved, but the difference between the RPLS model constructed before and after outlier exclusion was negligible. In conclusion, the bitterness of TCM decoctions can be accurately evaluated with the RPLS model constructed using e-tongue data.