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Capacity drop (CD) at overloaded bottlenecks is a puzzling traffic flow phenomenon with some internal and complicated mechanisms at the microscopic level. Capacity drop is not only important for traffic flow theory and modelling, but also significant for traffic control. A traffic model evaluating traffic control measures needs to be able to reproduce capacity drop in order to deliver reliable evaluation results. This paper delivers a comprehensive overview on the subject from the behavioral mechanism perspective, as well as from microscopic and macroscopic simulation points of view. The paper also conducts comparable studies to replicate capacity drop at freeway ramp merges from both macroscopic and microscopic perspectives. Firstly, the subject is studied using the macroscopic traffic flow model METANET with respect to ramp merging scenarios with and without ramp metering. Secondly, one major weakness of commercial microscopic traffic simulation tools in creating capacity drop at ramp merges is identified and a forced lane changing model for ramp-merging vehicles is studied and incorporated into the commercial traffic simulation tool AIMSUN. The extended AIMSUN carefully calibrated against real data is then examined for its capability of reproducing capacity drop in a complicated traffic scenario with merging bottlenecks. The obtained results demonstrate that reproducible capacity drop can be delivered for the targeted bottlenecks using both macroscopic and microscopic simulation tools.

Pull-up, as an important physical fitness test event of the “National Student Physical Health Standard”, is known as a difficult physical fitness test event. To improve the assessment criteria of pull-ups, this paper uses the functional near-infrared spectroscopy (fNIRS) to monitor the changes and activation of oxyhemoglobin (HbO) signals in the brain motor cortex of people with different body mass indexes (BMIs) during the pullup assessment. Then the relationship between BMIs and evaluation criteria is discussed. After collecting and analyzing experimental data of 18 recruited college students, it is found that the number of pull-ups performed by people with different BMIs is different when they reach the peak state of brain activation. The results of the study indicate that different assessment criteria should be adopted for different BMI groups. It is suggested that the BMI should be introduced as one of the test indexes in the examination of pull-ups event in “National Student Physical Health Standard”.

Background: Previous studies concerning the effect of plasma hemoglobin (HB) and other factors that may modify the risk of death in people living with HIV/AIDS (PLHIV) treated with antiretroviral therapy (ART) are limited. Results: Higher HB was independently linked to a lower death risk in PLHIV, with a decrease of 29% (13%, 43%) per standard deviation (SD) increment after adjusting for CD4, VL and other potential factors [hazard ratio (HR): 0.71, 95% confidence interval (CI): 0.57-0.87, P

Capacity drop at congested freeway bottlenecks is well known with a lot of field observations. This paper studies coordinated ramp metering (RM) and mainstream traffic flow control (MTFC) as well as their integration (RM+MTFC) for freeway traffic, with particular attention to effects of capacity drop on the performance of traffic control measures. Via mathematical analysis and comprehensive simulation studies under an optimal control framework, the work has revealed a capacity-drop-related mechanism that MTFC and ramp metering are based on to take effects, and obtained a number of important conclusions: (1) applications of any control measure (RM, MTFC, or RM+MTFC) in freeways are justified by the existence of capacity drop in field; (2) an appropriate usage of the control measures can effectively prevent the activation of potential bottlenecks on freeways and hence avoid capacity drop; (3) any control measure is beneficial for a large majority of the driver population in a freeway network if it can manage to increase the accumulated total network exit flow; (4) it is a common misconception that ramp metering would simply transfer traffic loads from the freeway mainstream to on-ramps. The work has also highlighted the strengths, weaknesses, and applicability of ramp metering and MTFC.

Due to the multipoint excitation and simultaneous detection strategy applied, spinning-disk confocal microscopy (SDCM) results in an increased imaging speed compared to conventional confocal microscopy. Additionally, the super-resolution radial fluctuations (SRRF) approach can further improve the imaging resolution of SDCM in 3D imaging at the cost of imaging time due to the large amounts of data acquisition and the increased risk of photo-bleaching and photo-toxicity due to the multiple excitations. Here, we propose a deep learning-based method for 3D SDCM, where the neighboring pixels in $z$ -scanning slices are taken into account for 3D reconstruction. Consequently, high-quality imaging slices can be reconstructed directly from the SDCM stacks with a single scan. The image quality achievable with this SRRF-Deep method is comparable with the SRRF method, whereas it achieves image reconstruction about 30 times faster using 100 times fewer images. Thus, practicality of the SDCM system can be significantly improved in 3D imaging.

High-performance elastic supercapacitors represent a promising kind of energy storage devices that can be employed in soft robotics and wearable electronics. The development of novel functional materials as supercapacitor electrode is still tremendously challenging. In the present work, the conductive polyvinyl alcohol–graphene oxide–polypyrrole (PVA–GO–PPy) composite hydrogels are fabricated through in situ polymerization of pyrrole in the presence of PVA and GO and subsequent freeze-thawing. Owing to the unique porous layered-wrinkle network and functional component of PVA–GO–PPy composite hydrogels, the as-prepared hydrogels exhibit lightweight, elasticity, compressibility, formability and softness. Furthermore, the mechanically robust and microstructured PVA–GO–PPy composite hydrogels are used to construct an elastic symmetric solid-state supercapacitor with good electrochemical performance. The device exhibits long-term compression/recovery elasticity under 50% strain, and even the volumetric capacitance retention is still about 81% when the strain is up to 80%. The excellent compression/recovery elasticity and good mechanical integrity of the high-performance supercapacitor based on PVA–GO–PPy composite hydrogel open up new opportunities for next-generation electronic devices in the practical application.

The alginate/reduced graphene oxide composite hydrogels with hierarchical network structures were synthesized through the hydrothermal treatment of graphene oxide and alginate in an aqueous solution followed by ionically cross-linking of metal ions. The network of reduced graphene oxide was prepared via self-assembly of graphene nanosheets in the presence of alginate during the hydrothermal process; then, the polymer network of alginate was obtained by ionically cross-linking, forming the composite hydrogel. The effect of metal ions on the physical properties of the composite hydrogels was investigated. The prepared alginate/reduced graphene oxide composite hydrogel cross-linked by Fe3+ ions showed higher compression strength and lower swelling ratio. Moreover, due to the synergetic interaction between graphene and alginate, the composite hydrogels exhibited the improved dye adsorption performance, especially for cationic dyes. Even after ten adsorption/desorption cycles, the composite hydrogels can retain more than 90% dye adsorption capacity. The results indicated that the composite hydrogel with good stability, adsorption and regeneration ability could be a promising candidate for dye removal from waste aqueous solutions.

Airy beam light-sheet illumination can extend the field of view (FOV) of light-sheet fluorescence microscopy due to the unique propagation properties of non-diffraction and self-acceleration. However, the side lobes create undesirable out-of-focus background, leading to poor axial resolution and low image contrast. Here, we propose an Airy complementary beam subtraction (ACBS) method to improve the axial resolution while keeping the extended FOV. By scanning the optimized designed complementary beam that has two main lobes (TML), the generated complementary light-sheet has almost identical intensity distribution to that of the planar Airy light-sheet except for the central lobe. Subtraction of the two images acquired by double exposure respectively using the planar Airy light-sheet and the planar TML light-sheet can effectively suppress the influence of the out-of-focus background. The axial resolution improves from ∼ 4 µ m to 1.2 µm. The imaging performance was demonstrated by imaging specimens of aspergillus conidiophores and GFP labeled mouse brain section. The results show that the ACBS method enables the Airy beam light-sheet fluorescence microscopy to obtain better imaging quality.

Background: Autophagy is important for cellular survival under numerous stimuli. Previous studies have demonstrated that endogenous glucocorticoids (GCs) could induce autophagy, contribute to bone metabolism and development under physiological condition, but the precise mechanisms involved are unknown. Methods: Mouse embryonic osteoblastic precursor cells, MC3T3-E1 cells, were treated with low dose of GCs (10-8M dexamethasone, Dex) and/or autophagy inhibitor, 3-methyladenine (3-MA) for different time periods. Gene interference with serum- and glucocorticoid induced kinase-1 (SGK1) was performed before above stimulations. After that, CCK-8 assay was performed to determine cell viability and the flow cytometry was performed to detect the apoptosis rates of the osteoblast cells. The expressions of SGK1, phosphorylated-FOXO3a (p-FOXO3a)/FOXO3 and autophagy-related proteins were detected with the western blotting. Results: A low dose (10-8M) of Dex induced a significant time-dependent increase in the expression and activation of SGK1 in MC3T3-E1 cells，accompanied by an increase in cell viability and decrease in cell apoptosis. 3-MA significantly inhibited the viability-promoting effect of Dex. Moreover, we found that Dex increased LC3II and Beclin-1 levels and decreased SQSTM/p62 levelin a time-dependent manner, which could be attenuated by pretreatment with 3-MA. Transfection of MC3T3-E1 cells exposed to Dex with shRNA-SGK1 resulted in a significant reduction in cell viability, and an increase in apoptosis. 3-MA further aggravated the effects of SGK1 inhibition on cell viability and apoptosis. Knocking down SGK1 before Dex exposure significantly downregulated p-FOXO3a/FOXO3, suppressed LC3II and Beclin-1 levels and increased SQSTM/p62 levels in MC3T3-E1 cells, which could be amplifies by 3-MA. Conclusions: A low dose of GCs increased osteoblast viability by activating autophagy via SGK1/FOXO3a pathway.

The complementary beam subtraction (CBS) method can reduce the out-of-focus background and improve the axial resolution in light-sheet fluorescence microscopy (LSFM) via double scanning a Bessel and the complementary beams. With the assistance of a compressed blind deconvolution and denoising (CBDD) algorithm, the noise and blurring incurred during CBS imaging can be further removed. However, this approach requires double scanning and large computational cost. Here, we propose a deep learning-based method for LSFM, which can reconstruct high-quality images directly from the conventional Bessel beam (BB) light-sheet via a single scan. The image quality achievable with this CBS-Deep method is competitive with or better than the CBS-CBDD method, while the speed of image reconstruction is about 100 times faster. Accordingly, the proposed method can significantly improve the practicality of the CBS-CBDD system by reducing both scanning behavior and reconstruction time. The results show that this cost-effective and convenient method enables high-quality LSFM techniques to be developed and applied.

Objective: The side-lobes of a Bessel beam (BB) create a severe out-of-focus background in scanning light-sheet fluorescence microscopy, thereby extremely limiting the axial resolution. The complementary beam subtraction (CBS) method can significantly reduce the out-of-focus background by double scanning a BB and its complementary beam. However, the blurring and noise caused by the system instability during the double scanning and subtraction operations degrade the image quality significantly. Therefore, we propose a compressed blind deconvolution and denoising (CBDD) method that solves this problem. Methods: We use a unified formulation that comprehensively takes advantage of multiple compressed sensing reconstructions and blind sparse representation. Results: The simulations and experiments were performed using the microbeads and model organisms to verify the effectiveness of the proposed method. Compared with the CBS light-sheet method, the proposed CBDD algorithm achieved the gain improvement in the axial and lateral resolution of about 1.81 and 2.22 times, respectively, while the average signal-to-noise ratio (SNR) was increased by about 3 dB. Conclusion: Accordingly, the proposed method can suppress the noise level, enhance the SNR, and recover the degraded resolution simultaneously. Significance: The obtained results demonstrate the proposed CBDD algorithm is well suited to improve the imaging performance of the CBS light-sheet fluorescence microscopy.

Micro-sized electrochemical energy storage device is a prospective candidate to power the miniaturized electronic devices and micro-pseudocapacitor (MPC) is a typical one with high power density and long life span. Developing a versatile architectural design with high capacity delivering in a micrometer range is paramount for remarkable MPC constructions. Here, an interdigitated graphene framework (IGF) is developed using a facile 3D printing technique to enable the customized geometries as well as the superior support of metal oxide nanostructures. With this unique design, the IGF-supported NiO nanorod heterostructured microelectrodes deliver high specific capacity of 220.2 C g−1 (400.3 F g−1). When directly assembled to quasi-solid-state symmetric MPCs, the NiO filled one exhibits a remarkable device capacity of 197.5 mC cm−2. Robust MPC cycling stabilities are also demonstrated during 10000 charge and discharge cycles. In addition to the NiO based ones, MnO2 nanosheet filled MPCs are also fabricated, where a high device capacity and a good cycling stability are also exhibited. We expect that this novel 3D-printed IGF can pave the way for constructing state-of-the-art miniaturized electrochemical energy storage devices with customized geometries.

We introduce the portfolio assessment into the classroom teaching reform in the curriculum of Cell Engineering, a specialty course in bioengineeringbiotechnology. We established a complete classroom evaluation system that was divided the classroom assessment system of portfolio into four stages including the preparation stage, training stage, implementation stage and exhibition stage. We also discuss the feasibility and necessity of implementing the portfolio evaluation method in the course of cell engineering, the construction of evaluation system, and the key points and matters needing attention in the implementation process. The classroom reform is very productive, not only the classroom atmosphere has been activated, students' learning initiative and autonomy has been enhanced, but also the students' ability to analyze and solve professional problems related to cell engineering technology has been improved. The implementation of classroom teaching reform of this course can provide reference for other similar professional courses in colleges and universities.首次将成长记录袋评价法引入到高等院校生物类专业课程《细胞工程》的课堂教学改革中，构建了较为完备的课堂评价体系，将成长记录袋课堂评价体系的建立分为4个阶段，即准备阶段、演练阶段、实施阶段和作品展示阶段。并从实施成长记录袋评价法的可行性与必要性、评价体系的构建、执行过程中应注意的要点及事项分别展开论述。结果表明：通过该评价法的施行，不仅活跃了课堂气氛，增强了学生学习的主动性和自主性，还提高了学生分析、解决与细胞工程技术相关的专业问题的能力，执行效果良好。本课程课堂教学改革的实施，可为高校同类性质的其他专业课程提供借鉴与参考。.

Light-sheet fluorescence microscopy (LSFM) facilitates high temporal-spatial resolution, low photobleaching and phototoxicity for long-term volumetric imaging. However, when a high axial resolution or optical sectioning capability is required, the field of view (FOV) is limited. Here, we propose to generate a large FOV of light-sheet by scanning multiple focus-shifted Gaussian beam arrays (MGBA) while keeping the high axial resolution. The positions of the beam waists of the multiple Gaussian beam arrays are shifted in both axial and lateral directions in an optimized arranged pattern, and then scanned along the direction perpendicular to the propagation axis to form an extended FOV of light-sheet. Complementary beam subtraction method is also adopted to further improve axial resolution. Compared with the single Gaussian light-sheet method, the proposed method extends the FOV from 12 μm to 200 μm while sustaining the axial resolution of 0.73 μm. Both numerical simulation and experiment on samples are performed to verify the effectiveness of the method.

This paper compares three filtering approaches to real-time freeway traffic state estimation based on the first-order and second-order macroscopic traffic flow models using fixed and mobile data together data together. The significance of online estimation of traffic flow model parameters along with traffic flow variables is also investigated in the context of heterogeneous sources of sensing data. The results indicate that the traffic state estimator based on a second-order model outperforms those based on the first-order models. In addition, the online model parameter estimation is significant for traffic state estimation especially when the penetration rate of mobile sensors is lower than 20%.

Conducting polypyrrole (PPy) hydrogels are considered as one promising class of materials for high performance supercapacitors because they synergize the unique features of conducting polymers and hydrogels with three-dimensional porous network. PPy hydrogels are synthesized in the absence of any additional crosslinkers by using ammonium persulfate as the oxidizing agent and sodium dodecylsulfonate as the surfactant. The as-prepared hydrogels exhibit nanoparticle-based porous networks with high surface area and electrical conductivity. The effect of different oxidants on the formation and the morphology of PPy hydrogels are also studied. The facile synthesis method offers PPy hydrogels morphology-controllable nanostructures and good mechanical property, as well as scalable processability. Moreover, PPy hydrogels coated on carbon cloth as binder free electrodes are further used for the fabrication of a symmetric solid-state supercapacitor with good rate capability, cyclic stability and bendable performance. Based on the simple fabrication and electrochemical performances, this PPy hydrogel can be expected as a potential material for flexible energy storage device.

Nitrogen-doped graphene aerogels with three-dimensional network structures are fabricated using hydrothermal method which includes the reduction of graphene oxide by organic amine and self-assembly of reduced graphene oxide. The effect of amine-containing compounds including aniline, 2-aminoethanol, ethylenediamine, melamine and chitosan on the assembly of nitrogen-doped graphene aerogel is investigated. The microstructure and chemical composition of nitrogen-doped graphene aerogels are characterized. The results reveal that nitrogen-doped graphene aerogel prepared using aniline as nitrogen source possesses a large specific surface area, high nitrogen content, good mechanical strength and excellent electrical conductivity. Based on these features, the as-prepared nitrogen-doped graphene aerogel shows high performance in electrochemical detection of dopamine in the presence of uric acid and ascorbic acid. Given the facile and scalable processability of aerogels, the proposed nitrogen-doped graphene aerogels are expected to have potential applications in sensors and other related devices.

Three-dimensional porous sponge with good mechanical strength, high absorption capacity and recyclability is of scientific and technological interest. In this work, graphene oxide has been incorporated into poly(vinyl alcohol)–chitosan sponge during acetalization reaction of poly(vinyl alcohol) for the fabrication of macroporous and amphiphilic sponges. Mercury intrusion porosimetry and scanning electron microscopy indicate that the as-prepared sponges have interconnected open-cell structures. The incorporation of graphene oxide and the interconnected macroporous structures in the amphiphilic sponges endow them with improved absorption capacity for both water and organic liquids. Moreover, the absorbed liquids can be effectively collected through simple squeezing and the sponges can be used repeatedly while maintaining a relative high absorption capacity. The simple fabrication and improved performance of the resulting sponges suggest that they have potential industrial applications.

Elastic conducting hydrogel is a promising candidate for the construction of high-performance electronic devices because of the unique mechanical and electrical features of conducting hydrogel with three-dimensional network. But conducting polymers are considered to be inherently rigid due to the conjugated chains in the macromolecular structures, leading to poor processability. Making conducting polymer hydrogels elastic by a rational and facile design is paramount for the construction of remarkable electronic device. Here, elastic polypyrrole (PPy) hydrogels reinforced by TEMPO-oxidized cellulose are obtained in the presence of methyl orange and FeCl3 during the static polymerization and self-assembly process. The as-prepared hydrogels exhibit one-dimensional nanotubes-based porous networks with electric conductivity, high elasticity and mechanical stability. With this special design, the symmetric quasi-solid-state supercapacitor fabricated by PPy hydrogels reinforced by TEMPO-oxidized cellulose electrodes deliver good electrochemical performance and can be connected in series as an electronic circuit to light up a LED bulb. All of the characteristics of the resulting PPy hydrogels reinforced by TEMPO-oxidized cellulose open an avenue for potential energy storage applications.

The main research about the preparation of the conducting polymer/graphene composite hydrogel has been focused on the hydrothermal synthesis or the external gel accelerator. Herein, the composite hydrogel based on graphene oxide (GO) and polypyrrole (PPy) and polyaniline (PANI) is fabricated via vapor-liquid interfacial synthesis. FeCl3 and GO are dispersed in an aqueous solution. Then, the polymerization of pyrrole and aniline occurs on the interface between their vapor and the above aqueous solution. The effect of FeCl3 and GO on formation, morphology and performance of composite hydrogel of GO/PPy/PANI is investigated. Furthermore, the specific capacitance of hydrogel is larger than that of composite film obtained without the addition of GO. After 2000 electrochemical cycles at a scan rate of 1 A g−1, about 91% of the specific capacitance of GO/PPy/PANI composite hydrogel is kept, indicating the enhanced cyclic stability of composite hydrogel. Moreover, graphite paper can be coated by GO/PPy/PANI composite hydrogels and used as binder-free electrodes to construct a flexible solid-state symmetric supercapacitor with excellent cyclic stability and rate capability. This work reveals an easy, efficient, and scalable route for the preparation of the conducting composite hydrogel with improved electrochemical performance.