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A phase shift that is caused by the machining errors of independent circuits would greatly affect the efficiency of the power combination in traditional multi-beam structures. In this paper, to reduce the influence of the phase shift and improve the output power, a multi-beam shunted coupling sine waveguide slow wave structure (MBSC-SWG-SWS) has been proposed, and a multi-beam overmoded flat-roofed SWG traveling wave tube (TWT) based on the MBSC-SWG-SWS was designed and analyzed. A TE10-TE30 mode convertor was designed as the input/output coupler in this TWT. The results of the 3D particle-in-cell (PIC) simulation with CST software show that more than a 50 W output power can be produced at 342 GHz, and the 3 dB bandwidth is about 13 GHz. Furthermore, the comparison between the single-beam sine waveguide (SWG) TWT and the multi-beam overmoded SWG TWT indicates that the saturated output power of the multi-beam overmoded SWG TWT is three times more than that of the single beam SWG TWT.

DC microgrids are growing in popularity due to their advantages in terms of simplicity and energy efficiency while connecting dc sources and dc loads. In traditional hierarchical schemes, optimization and control are implemented at different time scales. The loose integration lowers its energy efficiency and makes it hard to achieve real-time optimization. Even a slight disturbance can result in deviations of bus voltages and output currents from their optimal operating points. Additionally, most real-time control schemes cannot guarantee the boundedness of individual bus voltages. Targeting these problems, a distributed optimal control algorithm is presented in this article for dc microgrids to minimize operation loss (converter loss and distribution loss) in real time and maintain all bus voltages within predefined ranges. First, the Karuch–Kuhn–Tucker condition of the original constrained optimization problem is converted to an equivalent optimality condition, which is suitable for control design. Then, a distributed control algorithm is designed to drive the system's operating condition toward the optimal one. Convergence to the optima is guaranteed through rigorous Lyapunov-based stability analyses. Finally, simulation studies with a detailed switch-level model demonstrate the merits of the proposed controller.

Smith-Purcell radiation (SPR) is a kind of electromagnetic wave radiation that happens when an energetic beam of electrons passes very closely parallel to the surface of a ruled optical diffraction grating. The frequency of radiation waves varies in the upper and lower space of the grating for different electron velocity, satisfying the SPR relationship. In this study, a Fano-resonant metasurface was proposed to steer the direction of the SPR waves at the fixed resonant frequency by changing the velocity of the electron beam without varying the geometric parameters or adding extra coupling structure. The maximum emission power always locates at the resonant frequency by utilizing the integration of the Poynting vector. The relative radiated efficiency can reach to a maximum value of 91% at the frequency of 441 GHz and the efficiency curve has a dip when the direction of SPR is nearly vertical due to the high transmission. There is a great consistence of steering radiation angle from 65 degrees to 107 degrees by altering the velocity of electron beam from 0.6c to 0.95c both in analytical calculation and PIC (particle-in-cell of CST) simulation at terahertz frequencies, where c is the speed of light in vacuum. Furthermore, the destructive interference of Fano resonance between the magnetic mode and the toroidal mode shows the underlying physics of steering SPR in a fixed frequency. Our study indicates that the proposed structure can produce direction-tunable THz radiation waves at resonant frequency by varying the velocity of the electron beam, which is promising for various applications in a compact, tunable, high power millimeter wave and THz wave radiation sources.

The progression of agricultural production, ever-increasing industrialization, population boom, and more water-concentrated lifestyles has placed a severe burden on Yellow River Basin’s existing water resources, particularly in the current century. In the context of resource and environmental constraints, improving the green efficiency of agricultural water use (AWGE) is an important measure for alleviating the shortage of water resources as well as meeting the intrinsic requirement to promote the green transformation and upgrading of agriculture. This study used the Super Slack-Based Measure (Super-SBM) to measure the AWGE of 87 regions in the Yellow River Basin from 2000 to 2019. Based on spatial and temporal perspectives, it applied Exploratory Spatial Data Analysis (ESDA) to explore the dynamic evolution and regional differences in AWGE. Then, this study used a spatial econometric model to analyze the main factors that influence AWGE in the Yellow River Basin. The results show that, firstly, the AWGE of the Yellow River Basin shows a steady upward trend from 2000 to 2019, but the differences among regions were obvious. Secondly, the AWGE showed an obvious spatial autocorrelation in the Yellow River Basin and showed significant high–high and low–low agglomeration characteristics. Thirdly, rural per capita disposable income and effective irrigation have a positive influence on AWGE, while rural labor transfer, the input intensity of agricultural machinery and water structure have a negative influence. The spatial econometric model regression results show that the influence factors of AWGE in the Yellow River Basin showed significant spatial spillover effects and spatial heterogeneity in their effect. Finally, when improving AWGE in the Yellow River Basin, plans should be formulated according to local conditions. The results of this study can provide new ideas on the study of AWGE in the Yellow River Basin and provide references for the formulation of regional agricultural water resource utilization policies as well.

Determining whether epiphytic bryophytes have ecological preferences for woody plants remains difficult. Here, our primary aim in developing the torus-translation test is to evaluate the associations between epiphytic bryophytes and woody plants at the species, genus, or family levels in a 100 m × 100 m forest dynamics plot in a temperate, deciduous broad-leaved forest (China). We collected all the epiphytic bryophyte species on woody plants and recorded the woody plant species in the 1-ha plot in 2020. All the epiphytic bryophytes on the trees from the ground level up to 2 m were collected. We recorded 988 epiphytic bryophyte specimens belonging to 61 species in 254 woody plants. The Torus-translation test showed that 93.44% (57/61), 93.44% (57/61), and 98.36% (60/61) of the bryophyte species were significantly positively associated with the family, genus, and species of woody plants, respectively. A total of 317, 563, and 857 significant positive associations concerning the family, genus, and species of the woody plants were observed among the 61 examined bryophyte species. In addition, few significant negative associations were identified regarding the family, genus, and species of woody plants. More rare bryophyte species were positively correlated with woody plants than dominant bryophyte species. Our study demonstrates that most epiphytic bryophytes exhibit ecological habitat preferences for woody plants. These observations highlight the importance of the species composition of woody plants with respect to the maintenance of epiphytic bryophytes’ diversity. Epiphytic bryophytes’ growth preference for woody plants, especially rare bryophyte species, should be considered in the process of bryophyte diversity conservation in temperate, deciduous broad-leaved forests.

The Terahertz (THz) traveling wave tube (TWT) is developed for demands of broad applications, such as broad bandwidth communications, biomedicine, security check, basic subject research, etc. Through solved and grasped key technologies of THz TWT, some THz TWTs has been designed, fabricated and measured at frequency W-band, G-band and J-band. In this paper, the research progresses of THz TWT in Aerospace Information Research Institute, Chinese Academy of Sciences (AIRCAS) will be described.

Besides transition radiation (TR) and synchrotron radiation (SR), Smith-Purcell radiation (SPR) is a simple method to generate powerful terahertz emission. Yet, as the distance from grating surface to electron trajectory increases, the SPR intensity decays exponentially due to the effective interaction range[1] ${h_{\operatorname{int} }} = \frac{\lambda }{{4\pi }}\beta \gamma $. The radiation efficiency is greatly reduced beyond the effective interaction range especially for large diameter beams. To increase the coupling efficiency, an inclined flat electron beam is used in this paper. Meanwhile, the Fabry-Perot resonator arrays take place of the ordinary grating to achieve higher radiation power. This new method of SPR reduces the requirement of electron beam and enhances the radiation intensity. To verify the theory, an electron gun from SJTU is used in experiment, the results of which agree with theoretical analyses and simulations..

Diaphragm wall structure retaining excavation of subway stations in soft soil generally involves large investments and considerable construction risks. A reasonable design is expected to pr...

Phosphorus (P) deficiency is an important challenge the world faces while having to increase crop yields. It is therefore necessary to select maize (Zea may L.) genotypes with high phosphorus use efficiency (PUE). Here, we extensively analyzed the biomass, grain yield, and PUE-related traits of 359 maize inbred lines grown under both low-P and normal-P conditions. A significant decrease in grain yield per plant and biomass, an increase in PUE under low-P condition, as well as significant correlations between the two treatments were observed. In a genome-wide association study, 49, 53, and 48 candidate genes were identified for eleven traits under low-P, normal-P conditions, and in low-P tolerance index (phenotype under low-P divided by phenotype under normal-P condition) datasets, respectively. Several gene ontology pathways were enriched for the genes identified under low-P condition. In addition, seven key genes related to phosphate transporter or stress response were molecularly characterized. Further analyses uncovered the favorable haplotype for several core genes, which is less prevalent in modern lines but often enriched in a specific subpopulation. Collectively, our research provides progress in the genetic dissection and molecular characterization of PUE in maize.

A facile and efficient way in optimizing thermoelectric performance of Bi2Te3 alloy was reported through synergy of Pb acceptor doping and superstructure modulation. By varying the amount of Pb doping, the substitutional defect $${\text{Pb}}^{\prime}_{\text{Bi}}$$, arranging along the c-axis of PbBi2Te4 and PbBi4Te7 and acting as electron acceptor and superstructure, was formed successively in the Bi2Te3 matrix. This significantly reduced the lattice thermal conductivity and suppressed the bipolar effect. The figure of merit was enhanced and modulated, exhibiting a peak ZT of 1.06 and a broadened and optimized average ZT of 0.9 in a wide temperature range of 323–503 K.

Single-phase inverters are widely installed to integrate distributed generations into microgrids. To further improve the reliability and flexibility, several inverter modules connected in parallel are usually preferred. Besides achieving bus voltage regulation, another control objective of parallel-inverter systems is to guarantee load current sharing performance among multiple inverter modules. To attain these objectives in the presence of physical differences and uncertain system parameters, advanced control schemes are needed. In this study, a state-feedback decentralised adaptive control algorithm is firstly presented for single-phase parallel-inverter systems with unknown system parameters. Adaptive laws are designed to compensate for the uncertainties. In addition, the proposed control algorithm is decentralised in the sense that only local information is required for each inverter's controller. To overcome the practical problem that not all system states are available due to the presence of the unknown system parameters and load current, an output-feedback version of the decentralised adaptive controller is introduced through observers. The closed-loop system stability is proved via Lyapunov analysis. Finally, extensive simulation studies on parallel-inverter systems of different levels of detail are conducted to illustrate that the proposed control algorithm can provide satisfactory voltage regulation and current sharing performance under various loading conditions.

Atmospheric PM 10 (particulate matter with aerodynamic diameter per - and polyfluoroalkyl species (PFASs) in the PM 10 were measured. The total concentration of ionic PFASs ranged from 21.8 to 87.0 pg/m 3 , and the mean concentration of ionic PFASs during the day (42.6 pg/m 3 ) was slightly higher than that at night (35.1 pg/m 3 ). Generally, diurnal variations in the levels of ionic PFASs were consistent with those in the PM 10 concentrations. Perfluorooctanoic acid (PFOA, 23.5–33.7%), perfluoropentanoic acid (PFPeA, 28.3–39.9%) and perfluorobutyric acid (PFBA, 17.1–20.1%) accounted for the dominant compositional contributions. Significant positive correlations ( p 3 implied that oxidative degradation (O 3 served as the main oxidant) in the period of non-heating may affect the short-chain PFASs. The clustering analysis of a 72-h backward trajectory indicated that cross-provincial transport contributed to ionic PFASs at the sampling sites. Compared with ingestion via daily diet, the inhalation of PM 10 exhibited an insignificant contribution to the estimated average daily intakes ( ADI s) of PFASs by different age groups. In addition, the calculated hazard ratios ( HR s) for the non-cancer respiratory risk, based on the air concentrations of PFOA and perfluorooctane sulfonate (PFOS), also manifested lower non-cancer risk through inhalation exposure. Capsule The effects of heating and non-heating activity and diurnal variation on the concentrations of PFASs, dominated by PFOA, PFPeA, and PFBA in PM 10 , were determined, and atmospheric trans-provincial input served as an important source.

Mobile crowdsensing (MCS) has now become an effective paradigm to collect massive data for various sensing applications. However, the interactions between mobile users and the platform, and the data release to third parties, pose severe challenges of privacy leakage for MCS systems, such as the leakage of users' identities and locations. Although several works on MCS have explored the privacy issues in task allocation, incentive, and data reporting, there is still a lack of a comprehensive privacy preserving framework for MCS to protect the privacy of users throughout users' involvement in crowdsensing tasks. In this article, we divide the life cycle of each crowdsensing task in MCS into four phases: task allocation, incentive, data collection, and data publishing, and design a privacy-preserving framework for MCS to protect users' privacy in the whole life cycle of MCS.

In this work, the microstructure evolution in the near-surface of tungsten under hydrogen (H) plasma exposure conditions was observed by means of scanning electron microscopy (SEM), plasma focused ion beam (FIB) and transmission electron microscopy (TEM) techniques. Blisters, with existing dislocations distributed around obviously, were observed beneath the tungsten surface when the exposure temperature was 573 K, which was rarely reported in previous studies. However, H bombardment at 1273 K did not lead to the formation of blister-like microstructures. Correspondingly, irradiation hardening occurred after low temperature exposure, but not after high temperature exposure, according to the Berkovich nano-indentation experiments. In order to characterize the indentation size effect and irradiation hardening behavior of plasma-exposed materials, a mechanistic model was proposed for the hardness-depth relationship. A good agreement between the experimental indentation data and theoretical results revealed that plasma-induced dislocations play a dominant role in determining the increase of hardness for H plasma-exposed tungsten.

A self-designed experimental device was employed to simulate the pyrolytic dismantling process of selected electronic wastes (E-wastes), including printed wiring boards (PWBs) and plastic casings. The generated particulate matter (PM) of different particle sizes, carbon monoxide (CO) and carbon dioxide (CO2) were determined, and the corresponding emission factors (EFs) were estimated. Finer particles with particle sizes of 0.4–2.1 μm accounted for 78.9% and 89.3% of PM emitted by the pyrolytic processing of PWBs and plastic casings, respectively, and the corresponding EFs were 9.68 ± 4.81 and 18.49 ± 7.2 g/kg, respectively. The EFs of CO and CO2 from PWBs and plastic casings were 55.9 ± 26.9 and 1182 ± 439 g/kg, and 133.6 ± 34.6 and 2827 ± 276 g/kg, respectively. Compared with other emission sources, such as coal, biomass, and traffic exhaust, the EFs of E-wastes were relatively higher, especially for PM. There were significant positive correlations (p

Hemolytic toxicity of small molecules, as one of the important ADMET end points, can cause the lysis of erythrocytes membrane and leaking of hemoglobin into the blood plasma, which leads to various side effects. Thus, it is very crucial to assess the hemolytic potential of small molecules during the early stage of drug development process. However, so far there is no computational model to predict the human hemolytic toxicity of small molecules. To this end, we manually curate the hemolytic toxicity data set for the small molecules experimentally evaluated on the human erythrocytes, develop the first machine-learning (ML) based models to predict the human hemolytic toxicity of small molecules, harness the genetic algorithm (GA) and ML based model to optimize human hemolytic toxicity based on the molecular fingerprint to derive "optimal virtual fingerprints (OVFs)" with the desired hemolytic/nonhemolytic property, and finally implement a free software for the users to predict/optimize the human hemolytic toxicity with ML and GA in the automatic manner.

The objective of this study was to establish a novel isothermal amplification method for detection of heat-labile enterotoxin (LT-I)-producing Escherichia coli. Loop-mediated isothermal amplification (LAMP), cross-priming amplification (CPA), and isothermal multiple-self-matching-initiated amplification (IMSA) were developed and evaluated. Optimal conditions, specificity, and sensitivity tests were performed and compared to qPCR findings. All three methods could produce ladder-like products with LT-I positive samples, while no products were generated with the negative controls. The amplified products could be directly visualized as negative or positive in the isothermal amplification (IAM) tube, which saved time and prevented the possibility of cross-contamination. The detection limits of each assay were similar, and all three assays could directly detect the DNA of Escherichia coli in clinical samples successfully. This is the first report on the application of CPA and IMSA methods for the detection of LT-I. The findings suggest that the three assays may be important tools for the rapid detection of enterotoxigenic Escherichia coli (ETEC) in the clinic.

Fibrosis is the major pathological feature of chronic kidney disease (CKD). Aloe-emodin (AE), one of the main active compounds in Rhubarb, is widely used for renal protection. However, mechanisms implied in the modulation of kidney fibrosis after AE treatment for CKD remain elusive. Here, we explored the protective effects of AE for renal fibrosis and the involved mechanisms in vivo and in vitro. The renal fibrosis mice model was established by unilateral ureteral obstruction (UUO). We found that AE administration significantly ameliorated UUO-induced impairment of kidney, evidenced by improved histopathological abnormalities, body weight, and abnormal renal function in mice model. Immunohistochemical staining showed that TGF-β1 and Fibronectin expressions were significantly decreased in UUO mice compared with sham group. Meanwhile, we found that AE suppressed the activation of the PI3K/Akt/mTOR pathway induced by TGF-β1 in vivo. AE improved cell survival and decreased the level of fibrosis-related proteins under TGF-β1-induced fibrosis in HK-2 cells as well as in vitro. Furthermore, both wortmannin, an inhibitor of PI3K, and short-hairpin RNAs of PI3K knockdown abrogated TGF-β1-induced phosphorylation of Akt and mTOR, and decreased the suppression of fibrosis. These findings indicated that AE alleviated fibrosis by inhibiting PI3K/Akt/mTOR pathway in vivo and in vitro, which may provide a potential therapeutic option for CKD.

A microgrid is hard to control due to its reduced inertia and increased uncertainties. To overcome the challenges of microgrid control, advanced controllers need to be developed. In this paper, a distributed, two-level,communication-economic control scheme is presented for multiple-bus microgrids with each bus having multiple distributed generators &#x0028 DGs &#x0029 connected in parallel. The control objective of the upper level is to calculate the voltage references for one-bus subsystems. The objectives of the lower control level are to make the subsystems &#x02BC bus voltages track the voltage references and to enhance load current sharing accuracy among the local DGs. Firstly, a distributed consensus-based power sharing algorithm is introduced to determine the power generations of the subsystems. Secondly, a discrete-time droop equation is used to adjust subsystem frequencies for voltage reference calculations. Finally, a Lyapunov-based decentralized control algorithm is designed for bus voltage regulation and proportional load current sharing. Extensive simulation studies with microgrid models of different levels of detail are performed to demonstrate the merits of the proposed control scheme.

Direct current (dc) microgrids have been widely used in many critical applications. Such systems avoid unnecessary ac/dc conversions and can simplify control design. To achieve high-performance control of such system, advanced control algorithm needs to be designed. This paper presents a novel decentralized output constrained control algorithm for single-bus dc microgrids. The control objectives are to realize high-performance control of dc bus voltage, user-defined load sharing, and circulating current minimization. Unlike conventional control algorithms, the control algorithm can guarantee not only convergence but also bounded transient tracking error. By transforming the constrained system into an unconstrained system, the transient response of dc bus voltage can always stay within user-defined, time-varying bounds. Convergence of the transformed system can meet any transient performance requirement of the original system. Through proper control effort distribution, overall load demand can be shared among the distributed generators (DGs) according to predefined percentages. Accurate load sharing can indirectly minimize the harmful circulating currents among the DGs. Switch-level simulation and hardware experimentation with both single-bus and multiple-bus dc microgrids demonstrate the effectiveness of the proposed control design.

A wettability-controllable surface on carbon nanotubes (CNTs) was successfully constructed through directly grafting poly(N-isopropylacrylamide) (PNIPAM) from CNT surface (i.e. CNT-PNIPAM) via a facile method. The hybrid was employed as the support to prepare Pd catalyst (i.e. Pd/CNT-PNIPAM) for selective hydrogenation of cinnamaldehyde (CAL). The effects of thermoresponsive surface chemistry on catalytic performance were studied. Results showed that CNT-PNIPAM had the lower critical solution temperature (LCST) at about 37 °C. The hydrophilic surface of CNT-PNIPAM at 25 °C ( LCST), which exhibited the good adsorption properties for reactants in the reaction. The high Pd dispersion on Pd/CNT-PNIPAM as well as its good adsorption properties for CAL jointly resulted in an enhanced catalytic activity, meanwhile maintaining the selectivity to cinnamyl alcohol (COL) unchanged in comparison to CNT supported Pd catalyst (Pd/CNT).

The cascaded H-bridge (CHB) converter has become a promising candidate topology for utility-scale photovoltaic systems thanks to merits like modular structure, distributed maximum power point tracking (MPPT), and direct distribution grid access without medium-voltage transformers. However, module mismatches arising from nonideal elements like partial shading and parameter variations pose a technical challenge for such systems. If not dealt with properly, module mismatches can lead to adverse effects like unbalanced dc-link voltages of the modules, distortion of grid current, and reduced power generation. Conventional methods, such as reactive power compensation and level-shifted pulsewidth modulation (LS-PWM) based compensation, can alleviate this issue, but their performances are still limited by the allowable modulation range of power converters. In this paper, a compensation strategy combining reactive power compensation with a novel modulation method is proposed to extend the operating range in terms of module mismatch. Experimental results on a 2.4 kW/208 V single-phase setup are presented and have demonstrated that the proposed method can not only ride through a larger range of module mismatches but also improve solar power utilization and system efficiency owing to reduced switching events, noncompromised MPPT, and less required reactive power.

Biochar has shown to be a great product to control the bioavailability of potentially hazardous elements (PHE) in contaminated soils. Despite the advantages associated with the application of biochar in agricultural soils, relatively few studies have focused on the effects of biochar amendments on soil chemical properties, accumulation of arsenic, cadmium, zinc, and lead in rice tissues, and their availability in soil systems. The field experiment was conducted at the paddy soils in Hunan Province, China. The soil texture was sandy clay loam. Wheat-derived biochar was applied once to the experimental plots at the rates of 0, 10, 20, 30 and 40 t ha−1, and referenced as A0, A10, A20, A30, and A40, respectively. For PHE determination, soil samples and plant samples were digested with a mixed solution of HCl:HNO3 (4:1, V:V) and HCl:HClO4 (4:1, V:V), respectively, and the arsenic, cadmium, zinc, and lead in the digest solution were measured by ICP-MS (Thermo Fisher Scientific, USA). The soil available fraction of PHE (arsenic, cadmium, zinc, and lead) was extracted by diethylenetriamine pentaacetic acid (DTPA) and measured by inductively ICP-MS. Biochar amendment increased chemical properties of soil organic matter, pH, electrical conductivity, cation exchange capacity, nitrate nitrogen, and available phosphorus. Soil DTPA extractable arsenic, cadmium, zinc, and lead concentrations were significantly reduced. Arsenic, cadmium, zinc, and lead in rice shoots, and arsenic, cadmium, and zinc in roots significantly decreased after amendment. Concentrations in rice tissues positively and negatively correlated with the soil available fraction of PHE and soil chemical properties, respectively. Soil electrical conductivity negatively correlated with the soil available fraction of PHE. Concentrations of arsenic, zinc, cadmium, and lead in rice roots declined relative to increases of cation exchange capacity (arsenic, zinc), available phosphorus (cadmium), and nitric nitrogen (lead) content. Similar relationships were observed between cation exchange capacity and PHE in shoots. Biochar creates avoidance of PHE through regulating chemical properties through biochar sorption capacity. Cation exchange capacity, available phosphorus, and nitric nitrogen were the principle factors affecting roots uptake of arsenic, zinc, cadmium, and lead. Biochar soluble salts could decline availability of metals/metalloids in soils through precipitation. Wheat-derived biochar application is an alternative safe product to immobilize PHE in rice paddy soils by restricting the risk of PHE.

Conventional control solutions of the inverter-interfaced microgrids are usually designed based on models with fully decoupled subsystems. The negligence of the strong coupling due to power lines impedance leads to large transient line currents, which might trigger false protection. Besides, the droop-based control methods unnecessarily introduce system frequency and voltage deviations. To overcome these issues, a novel distributed control scheme is proposed for the inverter-interfaced microgrids in this paper. The objective of the primary control is to regulate the bus voltages and frequency while suppressing the transient line currents. The objective of secondary control is to maintain fair load sharing. Both primary control and secondary control are distributed and subsystems or control agents only require measurements from local and neighboring subsystems. The detailed control problem formulation, control design, and stability analysis are presented in this paper. The effectiveness of the proposed control solution is evaluated through extensive simulations based on both simplified and detailed models.

A single-bus DC microgrid can represent a wide range of applications. Control objectives of such systems include high-performance bus voltage regulation and proper load sharing among multiple distributed generators &#x0028 DGs &#x0029 under various operating conditions. This paper presents a novel decentralized control algorithm that can guarantee both the transient voltage control performance and realize the predefined load sharing percentages. First, the output-constrained control problem is transformed into an equivalent unconstrained one. Second, a two-step backstepping control algorithm is designed based on the transformed model for bus-voltage regulation. Since the overall control effort can be split proportionally and calculated with locally-measurable signals, decentralized load sharing can be realized. The control design requires neither accurate parameters of the output filters nor load measurement. The stability of the transformed systems under the proposed control algorithm can indirectly guarantee the transient bus voltage performance of the original system. Additionally, the high-performance control design is robust, flexible, and reliable. Switch-level simulations under both normal and fault operating conditions demonstrate the effectiveness of the proposed algorithm.

PM 2.5 (particulate matter with the aerodynamic diameter D p 2.5 concentrations, water-soluble ions and elements, carbonaceous components and ROS activity characterized by the dithiothreitol (DTT) assay were determined for the PM 2.5 samples collected in Beijing, China, over a whole year. Source apportionments of PM 2.5 and DTT activity were also performed. The mean ± standard deviation of PM 2.5 , DTT m (mass-normalized DTT activity) and DTT v (volume-normalized DTT activity) were 113.8 ± 62.7 μg·m −3 , 0.13 ± 0.10 nmol·μg −1 ·min −1 and 12.26 ± 6.82 nmol·m −3 ·min −1 , respectively. The seasonal averages of DTT m and DTT v exhibited peak values during the local summer. Organic carbon (OC), NO 3 − , SO 4 2− , NH 4 + and elemental carbon (EC) were the dominant components in the constituents tested. Higher concentrations of carbonaceous components occurred in autumn and winter compared with spring and summer. Based on the positive matrix factorization model (PMF), the simulation results of source apportionment for PM 2.5 in Beijing, obtained using the annual data, identified the main categories as follows: dust, coal combustion, secondary sulfate and industrial emissions, vehicle emissions and secondary nitrates. Most detected constituents exhibited significantly positive correlations with DTT v ( p v activity and source contribution to PM 2.5 manifested the sensitivity sequence of DTT v activity for the resolved sources as vehicle emissions > secondary sulfate and industrial emissions > coal combustion > dust. Capsule Based on a descending sequence of relative contribution, the diagnostic sources of DTT v activity in PM 2.5 from Beijing included primarily vehicle emissions, secondary sulfates and industrial emissions, coal combustion, and dust.

Glacial lakes are important freshwater resources in southern Tibet. However, glacial lake outburst floods have significantly jeopardized the safety of local residents. To better understand the changes in glacial lakes in response to climate change, it is necessary to conduct a long-term evaluation on the areal dynamics of glacial lakes, assisted with local observations. Here, we propose an innovative method of classification and stacking extraction to accurately delineate glacial lakes in southwestern Tibet from 1990 to 2020. Based on Landsat images and meteorological data, we used geographic detectors to detect correlation factors. Multiple regression models were used to analyze the driving factors of the changes in glacier lake area. We combined bathymetric data of the glacial lakes with the changes in climatic variables and utilized HEC-RAS to determine critical circumstances for glacial lake outbursts. The results show that the area of glacial lakes in Nyalam County increased from 27.95 km2 in 1990 to 52.85 km2 in 2020, and eight more glacial lakes were observed in the study area. The glacial lake area expanded by 89.09%, where we found significant growth from 2015 to 2020. The correlation analysis between the glacial lake area and climate change throughout the period shows that temperature and precipitation dominate the expansion of these lakes from 1990 to 2020. We also discover that the progressive increase in water volume of glacial lakes can be attributed to the constant rise in temperature and freeze–thaw of surrounding glaciers. Finally, the critical conditions for the glacial lake’s outburst were predicted by using HEC-RAS combined with the changes in the water volume and climatic factors. It is concluded that GangxiCo endures a maximum water flow of 4.3 × 108 m3, and the glacial lake is in a stable changing stage. This conclusion is consistent with the field investigation and can inform the prediction of glacial lake outbursts in southwestern Tibet in the future.

Lakes are important natural resources closely related to human survival and development. Based on PIE cloud computing platform, the study uses Landsat images and the empirical normalized water body index (ENDWI) to extract water body information of the large lakes in Sichuan province from 2000 to 2020 in the drought and rainy seasons, respectively, and uses the Mann–Kendall test to obtain the long-term trends of their area and climate. On this basis, the evolution of the lakes and their correlation with climate and human activities are analyzed. The results show that (1) In the past 20 years, the area of Lugu Lake, Qionghai Lake, and Luban Reservoir represent a decreasing trend, with Lugu Lake being the most affected. The area of Ma Lake, Three Forks Lake, and Shengzhong Reservoir increased, with the area of Shengzhong Reservoir increasing significantly; (2) During the drought season, all six lakes showed a decreasing trend in precipitation, with the most apparent decreasing trend for Lugu Lake (Slope = −0.8). Only Lugu Lake showed a decreasing trend in precipitation (Slope = −0.15) during the rainy season. The precipitation of Ma Lake, Three Forks Lake, Luban Reservoir and Shengzhong Reservoir showed a significant increasing trend (Slope value was greater than 1.96); (3) The temperatures of the remaining lakes all decreased in the drought season and increased in the rainy season, except that the temperature of Shengzhong Reservoir decreases throughout the year; (4) The area change of plain lakes is greatly affected by human activities, but the area of plateau lakes is are more impacted by climate. Our study improved the accuracy of long-term water body change monitoring with PIE-Engine Studio. Besides, the findings would provide reference for the implementation of sustainable water resources management in Sichuan Province.

Ying Chen,1– 3 Lei Zhang,1– 3 Fangxuan Li,4 Jindong Sheng,1 Changxiao Xu,1 Dan Li,1 Hu Yu,1 Wenxin Liu1 1Department of Gynecologic Oncology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, 300060, People’s Republic of China; 2Tianjin’s Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, 300060; 3National Clinical Research Centre of Cancer, Tianjin, 300060, People’s Republic of China; 4Department of Cancer Prevention, Tianjin Medical University Cancer Institute and Hospital, Tianjin, 300060, People’s Republic of ChinaCorrespondence: Ying ChenDepartment of Gynecologic Oncology, Tianjin Medical University Cancer Institute and Hospital, Huanhuxi Road, Hexi District, Tianjin, 300060, People’s Republic of ChinaEmail lychenying2004@126.comIntroduction: Photodynamic therapy (PDT) has been widely researched by cancer therapists in recent years. This study aims to establish a drug delivery system combining PDT and chemotherapy to show that chemotherapeutic drugs provide oxygen to PDT, while PDT promotes the release of chemotherapeutic drug.Methods: Firstly, poly(ethylene glycol)-lysine(Ce6)-block-poly(L-glutamate)-imidazole (mPEG-lys(Ce6)-PGA-AIM) was synthesized and self-assembled into micelles that exhibited pH- and ROS-responsiveness and buffering capacity. Perfluorohexanoate-modified cisplatin (FCP), as oxygen carriers, was encapsulated into mPEG-lys(Ce6)-PGA-AIM micelles. Then, the properties of micelles and their biological functions in vivo and in vitro were investigated.Results: The micelles exhibited remarkabe stability, pH regulated drug release, good biocompatibility and effective tumor penetration. Cellular uptake demonstrated the efficient endosome/lysosome escape of CFMs, which facilitates the intracellular drug release. Both in vitro and in vivo experiments reflected that CFMs with laser irradiation showed significantly improved therapeutic activity compared with single PDT or chemotherapy.Conclusion: Chemotherapy and PDT were combined in the form of mutual assistance to provide a promising strategy for clinical treatment.Keywords: chemotherapy, photodynamic therapy, dual-responsiveness, oxygen carriers

Folded Waveguide (FW) Traveling Wave Tubes (TWT) is a kind of high frequency, high power, and moderate bandwidth slow-wave structures. In many applications, FWTWT is a seductive choice. Such as radars, communication systems and electron counter measure. In this paper, a two-section folded waveguide at 0.108THz is designed to get 50W of average power. The structural parameters and dispersion characteristics of this folded waveguide are optimized through a detailed analysis. Influence of simulation parameters, angle dispersion, energy dispersion and roughness on output power are investigated using particle-in-cell (PIC) simulation. Analysis the phase velocity on the output power, and the results indicate that the output power can be increased by reducing the phase velocity. The simulation results shows that the maximum output power and gain are about 50W and 30dB at 0.108THz, and the bandwidth of this folded waveguide is about 10GHz, which is driven by an electron beam with operation voltage 13.2KV and current 0.08A.

In present work, we report a terahertz (THz) travelling wave tube (TWT) with two cascade sections, which has high power and broad-bandwidth. The operation voltage and operation current of electron beam are 17.18 kV and 71 mA, respectively. Using such electron beam, the peak power of TWT is 60 W at the frequency of 0.22THz. Besides, the gain is over 30 dB at over 6 GHz bandwidth. Such new THz TWT will be applicated in long-range radar and high-speed communication systems.

Printed electronics is a burgeoning additive manufacturing technique, which enabled extensive applications in micro/nano fabrication and flexible electronics. As a common printing material, metal oxide is employed in a variety of sensors and logic devices. However, synthesis of metal oxide ink with minimized particle size, uniform dispersion and appropriate rheological properties remains a challenge. In this study, we proposed two precursor-based inks for the printing of zinc oxide in nanoscale. The inks were tested using inkjet and dispensing printing method, respectively. The printed ZnO films showed porous nanostructures, which accommodates to the demands in sensor applications. Moreover, this study is also a demonstration of direct printing of metal oxide materials using precursor-based ink systems.

In this work we investigate the problem of uncertainty estimation for image-guided depth completion. We extend Deep Basis Fitting (DBF) for depth completion within a Bayesian evidence framework to provide calibrated per-pixel variance. The DBF approach frames the depth completion problem in terms of a network that produces a set of low-dimensional depth bases and a differentiable least squares fitting module that computes the basis weights using the sparse depths. By adopting a Bayesian treatment, our Bayesian Deep Basis Fitting (BDBF) approach is able to 1) predict high-quality uncertainty estimates and 2) enable depth completion with few or no sparse measurements. We conduct controlled experiments to compare BDBF against commonly used techniques for uncertainty estimation under various scenarios. Results show that our method produces better uncertainty estimates with accurate depth prediction.

Nine hydrothermal carbonization process waters (PWs) of poultry litter were prepared at 180, 220, and 260 °C for 1, 4, and 8 h, respectively. They were characterized with pH, EC (electric conductivity), DOC (dissolved organic carbon), TN (total nitrogen), NH4+-N, NO3−-N, etc. After diluted according to TN, the PWs were supplied as liquid nitrogen fertilizers and their phytotoxic and nutrition effects on lettuce germination and growth were studied. The results showed that the PWs from short time (1 h) were with low DOC/TN and DOC/NH4+-N and high NH4+-N/TN. Compared with the PWs from long time 4 and 8 h, they provided more NH4+-N and less DOC and resulted in lettuce with relatively high germination index (GI), dry biomass, and low antioxidant enzyme activities. Especially, the PW from 220 °C and 1 h significantly enhanced the dry weight by 196.3% relative to negative control of nitrogen deficiency. However, all the PWs led lettuce to an unhealthy condition, which decreased GI and the chlorophyll content and increased antioxidant enzyme activities. Furthermore, it was confirmed by linear regression that the ratios of DOC/TN, NH4+-N/TN, and DOC/NH4+-N were the determining indexes for evaluating the phytotoxicity and nutrition behavior of the PWs as liquid nitrogen fertilizers.

As an oxidase stress biomarker, 3-nitrotyrosine is closely associated with many cardiovascular diseases. Thus, early diagnosis and real time detection of 3-nitrotyrosine at bedside are highly important. Herein, we developed a handheld electrochemiluminescence (ECL) analysis device, which integrates printed circuit board (PCB) for electrical stimulation and smartphone for optical signals readout. Fast and accurate determination of 3-nitrotyrosine was achieved with Antibody/Ru(dcpy)32+@AuNPs/MoS2 modified Au electrode (Ab/Ru@AuNPs/MoS2) for ECL analysis. The linear range of 3-nitrotyrosine detection was from 10−8 mol/L to 10−6 mol/L with a detection limit of 8.4 × 10−9 mol/L. In addition, an Android application was developed to realize real time analysis of ECL emissions and results readout for detection. To confirm the usage of the device, spiked serum with different concentrations was tested and the results indicated the practical reliability and stability of this device. The operating procedure for ECL analysis in this device is extremely easy and electrical stimulation was adjustable from 0 V to 5 V for general ECL systems. Thus, we believe this handheld device for ECL analysis has extensive prospects for application in Point-of-care testing and health caring.