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In this study, we consider the introduction of new mobility services and technologies into the megacity of Beijing, China, as per developed strategy and action plans, in order to investigate their potential contribution to sustainable mobility. This includes population relocation (decentralization), the construction of new rail lines, the introduction of shared bike services as a feeder to subway stations, the electrification of passenger vehicles and the adoption of automated and shared vehicles. The well-established, system dynamics-based MARS model is adapted to Beijing and further improved via the inclusion of these new services, technologies and policies. We find that decentralization can have a profound effect on overall sustainability if not considered in conjunction with other policies and that new rail lines and shared bikes may only have benefits in specific zones. Shared and automated vehicles could increase VKT by 60% and reduce active and public transport trips by a quarter. As such, nuanced integrated policy approaches will be required that are similar to those currently in place, such as imposed car shedding and taxi fleet control.

In order to study the air gap magnetic field distribution and torque of axial-flux solid magnetic couplers with 9 pairs of permanent magnets, a layer model is firstly introduced, which divides the couplers into conductive and non-conductive areas. The two-dimensional magnetic scalar potential method is derived to solve the magnetic field strength in conductive areas and the magnetic scalar potential in non-conductive areas. Carter coefficient is introduced to correct the 3D end effects, and the formula of air gap flux density and torque is derived. Then， the distribution of 3D air gap magnetic field, eddy current and the influence of different working parameters on the characteristics of the torque are obtained by the finite element simulation software. Finally, a measure system of three-dimensional magnetic field and the magnetic drive experimental platform are built to measure the 3D air gap magnetic field and the torque. The experimental results are in good agreement with the results of theoretical calculation and the simulation analysis, which shows that the formula of the air gap flux density and the torque have high accuracy and can be used as a reference for further research on the transmission characteristics of eddy-current magnetic couplers.

In order to study the calculation formula of the electromagnetic torque and the transmission characteristics of the drum-type solid magnetic coupler (DSMC), a DSMC with 4 poles is used as the research object. The magnetic equivalent circuit model introducing the induced current is established, combining with Ampere's loop law and the 3-D magnetic effect to analyze and calculate the electromagnetic torque. The magnetic field distribution and induced current distribution of the coupler and the mechanical characteristic curve under different input speeds are obtained by using the finite element simulation software. By moving the conductor rotor axially and changing the relative position of the two rotors, the effects of different meshing lengths on the electromagnetic torque are obtained. Finally, a test platform is built to verify the electromagnetic torque results obtained by the theoretical calculation and the finite element simulation. The experimental results are basically consistent with the above results. The model provides guidance for the design and optimization of the DSMC.

Aiming at the speed regulation characteristics of slotted-type eddy-current couplers, the expression of the induced magnetic field generated by the induced eddy current is derived by using Ampère's law and the induced magnetic field is introduced into the equivalent magnetic circuit model. Then, the calculation formula of electromagnetic torque is derived in combination with Kirchhoff's law. The electromagnetic torque formula is combined with the expression of constant torque load and quadratic rate load respectively, and the theoretical formula of the speed regulation relationship under corresponding load conditions is obtained. The 3D finite element simulation and experiment are used to verify the proposed theoretical model of speed regulation. It is found that the proposed theoretical model has good accuracy in the case of small air gap length.

In order to study the transmission performance of slotted-type eddy-current couplers with radial misalignment, based on the theory of the equivalent magnetic charge theory, the copper which cuts the magnetic field line in motion is equivalent to permanent magnet. Combining with Coulomb's law, a calculation model of output torque is established in this study. The analysis of magnetic flux density, copper loss and output torque of couplers are all simulated by finite element software, and the maximum allowable value of radial misalignment is obtained. The results show that with the increase of radial misalignment, the induced magnetic field decreases during operation, which results in the increase of the magnetic flux density, the decrease of the copper loss and the torque, and the fluctuations of the copper loss and the output torque changing with time become more and more obvious. When the radial misalignment is less than 6 mm, the torque generated by the couplers can almost be remained accurately and the fluctuation of the torque is relatively stable.

A Ti/β-TCP composite porous scaffold with a hierarchical pore structure composed of 3D printed interconnected macroscopic pores and sintered microscopic pores was prepared by direct ink writing (DIW) 3D printing technology. This method can control the extrusion of composite ink at room temperature and produce a 3D scaffold using layer-by-layer deposition. We studied the effects of the β-TCP powder particle size, β-TCP/Ti powder ratio and solid loading on the rheological properties of the ink and optimised the DIW printing process parameters. After sintering, the compressive strength and elastic modulus of the composite scaffold reached 45 MPa and 1 GPa, which is close to the strength of human cancellous bone. The cell culture experiment confirmed that the composite scaffold had better biological properties than the pure titanium scaffold. The composite scaffold has satisfactory mechanical and biological properties, meeting the requirements for orthopaedic implants.

In order to solve the problem of calculating the air gap magnetic field and torque of slotted-type magnetic couplers, a subdomain analysis model is introduced. The magnetic couplers are divided into five regions along the axis, the boundary equations are established at the interfaces of each region. According to the alternating arrangement characteristics of yoke teeth and the conductor and the vector magnetic potential formulas in yoke teeth and the copper conductor disk are deduced respectively. Due to the end effect, Schwarz-Christoffel mapping is used to modify the coefficient of the flux density at the end face of the cogging. On the basis of obtaining the vector magnetic potential of the yoke iron and conductor respectively, the formulas of the air gap magnetic field and electromagnetic torque are deduced. The structure parameters of the slotted-type magnetic couplers are substituted into the theoretical model to calculate the axial air-gap magnetic field distribution and mechanical characteristic curves. By comparing the results with those obtained by finite element simulation, the accuracy of the theoretical model is verified and the cause of the error is analyzed.

ObjectiveTo investigate the resistance to pyrethroids， beta-cyhalothrin and fenitrothion as well as the frequencies of kdr and ace⁃1 alleles in Anopheles sinensis from three geographical populations in Chongming District， Shanghai.MethodsThe contact tube method recommended by WHO was used to determine mosquito resistance. The frequencies of kdr and ace⁃1 alleles in adult mosquitoes were determined by PCR amplification. The correlation between the frequencies of kdr alleles and insecticide resistance was analyzed by linear regression method.ResultsThe mosquito population near natural reserve （NF） was sensitive to deltamethrin， and the mortality rate was 100.00% at 24 h. The mosquito population with intensive breeding farms （HX） showed resistance to deltamethrin and beta-cyhalothrin， and the 24 h mortality was 48.00 % and 57.50 %， respectively. The 24 h mortality rate of the mosquito population with urban-rural integration area （AS） with suspected resistance to deltamethrin and beta-cyhalothrin was 84.40% and 86.00%. The 24 h mortality rate to Fenitrothion was 55.67%. There were 3 mutations in kdr gene locus 1014， and 7 mutated genotypes were detected， mainly L1014/L1014F and L1014F/L1014F. The mutation frequency of kdr allele in HX population was the highest （52.68%）. There was one mutation at site 119 of ace⁃1 gene， and three genotypes were detected， most of which were G119S mutation. There was a significant negative correlation between the frequency of kdr resistance allele and the mortality rate of beta-cypermethrin in An.sinensis populations （r2=0.930，P=0.036）. There was a significant negative correlation between the frequency of ace⁃1 resistance allele and the mortality rate of fenitrothion in An. sinensis populations from four habitats （r2=0.996，P=0.038）.ConclusionThe mutation frequency of insecticide resistance allele is associated with the development of mosquito resistance level. Therefore， comprehensive monitoring of resistance levels of An.sinensis in Chongming area should be continued to provide a basis for local mosquito resistance management.

Ticks are the second most harmful infectious agent in the world after mosquitoes and can transmit a variety of pathogens. The surveillance of pathogen in ticks is one of the important means for the prevention and control of tick-borne diseases and tick-borne pathogens. This paper reviewed the literature published in the past two decades on the principles， advantages， disadvantages and applications of current tick pathogen detection technologies. The paper introduced the development and application of various PCR technologies， and looks forward to the future direction. Finally， it points out that metagenomics represented by high-throughput sequencing will become the mainstream development direction of pathogen detection technology in the future.

Anesthesia management of Totally thoracoscopic cardiac surgery (TTCS) has been the subject of much debate and discussion. In this single center retrospective study, we summarize the experience of clinical anesthesia management for TTCS by review the medical records of our medical center and look forward to its future development. In this retrospective study, 103 patients (49 male and 54 female) were enrolled, the mean age was 56.7 ± 14.4 years old. The participants underwent Mitral Valve Replacement (MVR) + Tricuspid Valve Annuloplasty (TVA) (42, 40.8%), Mitral Valve Annuloplasty (MVA) + TVA (38, 36.9%), MVA (21, 20.4%), and MVR (2, 1.9%)，respectively. Intraoperative hypoxemia, radiographic pulmonary infiltrates, and pneumonia were observed in 19 (18.4%), 84 (81.6%), and 13 (12.6%) patients, respectively. The LOS of ICU and POD were as follows: MVR + TVA (55.1 ± 25h, 9.9 ± 3.5 d), MVA + TVA (56.5 ± 28.4h, 9.4 ± 4.2d), MVA (37.9 ± 21.9h, 8.1 ± 2.3d) and MVR (48 ± 4.2h, 7.5 ± 2.1d). No reintubation, reoperations, postoperative cognitive dysfunction, 30-day mortality were observed in the present study. The present study demonstrated that applying this anesthesia management for TTCS associated with acceptable morbidity, intensive care unit and postoperative hospital lengths of stay. The finding from the present study might provide some new approach for Anesthesia management of TTCS.

The coordinated optimization scheduling of the integrated energy systems is vital in multi-energy complementarity and hierarchical utilization. However, the centralized optimization is inferior to the distributed optimization of the large-scale multiregion integrated energy system (MRIES) in data processing capacity and information security. This study proposes a distributed computing architecture based on the edge computing unit (ECU), which takes the energy hub as the main body and sets the partitioning principle and method of MRIES. The ECU can finally realize the whole-system collaborative optimization of MRIES, which contains electrical, natural gas, and district heating networks through internal autonomous optimization and boundary information interaction with the cloud computing center. At the same time, an improved nested algorithm based on the consensus-alternating direction method of multipliers is proposed, which ensures the convergence of the mixed-integer linear program and effectively improves the convergence speed. Combining the advantages of the model and algorithm provides a theoretical and algorithmic support for the optimization research of the MRIES.

It is challenging to deal with the optimal scheduling problem of the multi-regional integrated energy system (MIES) precisely and efficiently due to its multi-dimensional nonlinear characteristics. This article proposes an iterative linearization approach to solve the complicated and nonlinear MIES optimization problem with a well-balanced trade-off between accuracy and computation efficiency. In particular, the proposed approach is a combination of the modified piecewise linearization (PWL) tactic and the sequential linear programming (SLP) algorithm. The modified PWL method is developed to improve the speed-accuracy trade-off of the linearization, while the SLP algorithm is used to linearize the multi-dimensional nonlinear functions and narrow the approximation error iteratively. In this way, accurate but highly nonlinear formulations such as heat network models in the variable flow and variable temperature (VF-VT) mode can be considered in the optimization and solved efficiently. Finally, the effectiveness of the given approach is validated in a day-ahead optimal scheduling case of a four-region MIES.

An AC electrified railway can interfere significantly with parallel underground pipelines in a public transportation corridor. Such interference may threaten the long-term transportation and the operational safety of the pipelines. Therefore, this paper presents a mathematical model to illustrate the electromagnetic coupling between an AC electrified railway and nearby parallel underground pipelines. As the basis of the engineering calculation, an integration simulation model based on CDEGS software, which included an electrified railway and pipeline system, was built and its correctness was validated by comparing it with a mathematical model. Also, the effects of electric traction load parameters, pipeline parameters, and soil structure parameters were analyzed, the results of which demonstrate the distribution characteristics of AC interference on parallel underground pipelines. Using a real case in China as an example, protection measures were introduced to decrease coupling interference and their effectiveness was verified by simulation calculations and field measurements.

A novel synthesis strategy for hierarchical polypyrrole nanopillar/silver nanoparticle arrays is designed and its application as an antibacterial surface and nonenzymatic H2O2 sensor is explored. The hierarchical structure is fabricated using a microporous membrane‐templated method by multiple steps. Using a polypyrrole nanopillar array as the matrix, silver nanoparticles can be uniformly reduced and stably anchored onto the nanopillar array by a redox reaction in a AgNO3 solution. The morphology, structural characteristics, conductivity, and reaction mechanisms of the composites are studied in detail. The incorporation of Ag nanoparticles not only significantly enhanced the antibacterial activity of the surface, but also contributed to the excellent ability to detect H2O2. This work provides a versatile approach to achieve the controlled fabrication of hierarchical metal‐conducting polymer composite structures and demonstrates them as promising multifunctional interfaces with antibacterial and sensing activity. [ABSTRACT FROM AUTHOR]

Utilizing plastic wastes as linker sources for metal–organic framework (MOF) synthesis is a green and sustainable methodology for the chemical upcycling of plastics. However, improving the depolymerization efficiency of polymers and avoiding highly corrosive solvents during the purification of the products remain significant challenges. Herein, we propose an approach to efficiently hydrolyze practical poly(ethylene terephthalate) (PET) wastes using aqueous dispersions of ultrasmall ZnO (6 nm) nanoparticles as the catalysts and subsequently synthesize five typical nano-MOFs by one-pot and two-pot strategies. The neutral hydrolysis of PET is greatly accelerated, with PET being completely depolymerized at 200 °C in 60 min with a terephthalic acid yield of 95.6%. The PET-derived MOF nanoparticles present high BET surface areas that are higher than or close to those of congeneric MOFs synthesized from petroleum-based and highly purified ligands. As a water absorbent, the two-pot MIL-101(Cr) exhibits high thermal stability with a water uptake capacity of 1327.3 mg g−1. For photocatalytic degradation of antibiotic pollutants, MIL-53(Al, Fe) samples derived from PET textiles show a high tetracycline removal efficiency of over 90% within 60 min without additives in an aqueous system, outperforming most of the conventionally prepared MOF catalysts. This approach disposes of discarded plastics in an eco-friendly way and produces value-added materials with excellent catalysis and adsorption properties. [ABSTRACT FROM AUTHOR]