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Plasma control of forebody asymmetric vortices is mostly achieved by means of dielectric barrier discharge (DBD) plasma actuators. However, DBD actuators suffer from some disadvantages such as a weak induced body force, a single-direction induced jet, and an unclear control mechanism. We carry out wind tunnel experiments involving the forebody vortex control of a slender body at high angles of attack using an innovative extended DBD actuator, which has a stronger capacity to induce an electric wind than a DBD actuator. Through synchronous measurements of the pressure distribution and particle image velocimetry (PIV), the spatiotemporal evolution of the dynamic interactions between plasma-actuation-induced vortices and forebody asymmetric vortices is analyzed. The influence of plasma discharge on the boundary layer separation around a slender body and the spatial topological structures of asymmetric vortices are further surveyed, as the optimized actuation parameters. Extended DBD actuators are found to be more capable of controlling asymmetric vortices than DBD actuators, and a linear proportionality of the sectional lateral force versus the duty ratio is achieved. There exists an optimal normalized reduced frequency (f + = 2π f p d/U ∞ = 2.39) for asymmetric vortex control under the present experimental conditions. The research results can provide technical guidance for the control and reuse of forebody asymmetric vortices.

The main purpose of this paper is to build an objective and effective environmental performance evaluation model of air pollution control. Based on the severe air polluted region in China, that is Beijing-Tianjin-Hebei region, this evaluation model consists of four parts, including economic benefits, public service, government management and development potential, and uses the balanced scorecard theory. The weights of the indexes are measured by comprehensive evaluation method, which combined entropy weight method and analytic hierarchy process (AHP). To test the applicability of the evaluation method to different stages, back propagation (BP) neural network is introduced to simulate air pollution control in the future. The results reveal that the environmental performance of air pollution control in Beijing had an upward trend during 2010–2016, and the trend would continue in the next five years. The environmental performance of Tianjin continuously increased, especially from 2014 to 2016. Tianjin has great potential of air pollution control in the future. The environmental performance of air pollution control in Hebei fluctuated from 2010 to 2016 and it dropped to the lowest level in 2015, which mainly due to the large increase in number of days with air quality levelⅡor above compared with 2014 and the nonsignificant growth in the amount of expenditure on atmospheric prevention and control, the amount of investment in the control of industrial pollution sources and the number of law enforcement personnel. Moreover, the environmental performance of air pollution control closely related with industrial structure, especially with the proportion of the tertiary industry. The upgrading of urban industrial structure and the coordinated development of green industry should be implemented to restructure the environmental transformation in air-polluted region.

Two innovative kinds of sliding discharge plasma actuators based on different formation hypotheses of forebody asymmetric vortices are designed using a slender body model. Particle image velocimetry and surface pressure measurements are synchronously used to compare the control effect of antiflow and along-flow sliding discharge actuators for a forebody asymmetric vortex at high angles of attack. The experimental results show that the two kinds of sliding discharge plasma actuators can effectively change the random lateral force caused by the asymmetric vortices, and a better control effect is manifested using the along-flow sliding discharge plasma actuator, which contributes to the approximately linear proportional control of the lateral force. This finding suggests that the convective instability of the forebody vortex system in the leeward region of the slender body has a significant influence on the random lateral forces and moments. Through improving the spatial stability of forebody vortices, the flow control efficiency can be effectively improved. An optimal pulse frequency exists in each of the three actuation modes, but it may vary due to the different geometry configuration of the plasma actuator. In this regard, the research findings will potentially provide technical guidance for improving the efficiency of plasma actuators and understanding the formation mechanism of asymmetric vortices.

Deep learning algorithms have achieved excellent performance lately in a wide range of fields (e.g., computer version). However, a severe challenge faced by deep learning is the high dependency on hyper-parameters. The algorithm results may fluctuate dramatically under the different configuration of hyper-parameters. Addressing the above issue, this paper presents an efficient Orthogonal Array Tuning Method (OATM) for deep learning hyper-parameter tuning. We describe the OATM approach in five detailed steps and elaborate on it using two widely used deep neural network structures (Recurrent Neural Networks and Convolutional Neural Networks). The proposed method is compared to the state-of-the-art hyper-parameter tuning methods including manually (e.g., grid search and random search) and automatically (e.g., Bayesian Optimization) ones. The experiment results state that OATM can significantly save the tuning time compared to the state-of-the-art methods while preserving the satisfying performance.

The development of next-generation high-maneuverability aircraft requires new technologies for controlling asymmetric separated vortices at high angles of attack. Plasma flow control is an emerging...

Grafting has been widely applied to melon (Cucumis melo L.) production to alleviate obstacles of continuous cropping and control soil-borne diseases. However, grafting often leads to a decline of fruit quality. For example, sometimes bitter fruits are produced on grafted plants. However, the underlying physiological mechanism still remains unclear. This study investigated the effects of different rootstocks on the taste of fruits of the Balengcui, an oriental melon cultivar, during summer production. The results showed that all grafted plants with Cucurbita maxima Duch. rootstocks produced bitter fruits, while non-grafted plants and plants grafted onto muskmelon rootstocks produced no bitter fruits. Liquid chromatography-mass spectrometry and metabonomic analysis were performed to investigate the mechanism underlying the occurrence of bitter fruits. Metabolite comparisons of fruits from plants grafted onto Ribenxuesong rootstocks both with non-grafted plants and plants grafted onto muskmelon rootstocks showed that 17 metabolites including phospholipids, cucurbitacins and flavonoids, exhibited changes. The three Cucurbitacins, Cucurbitacin O, Cucurbitacin C, and Cucurbitacin S, increased dramatically. The 10 phospholipids PS(18:1(9Z)/18:2(9Z,12Z)), PS(P-18:0/15:0), PA(18:1(11Z)/18:1(11Z)), PE(16:0/18:0), PS(O-16:0/17:2(9Z,12Z)), PI(16:0/18:2(9Z,12Z)), PA(15:0/22:6(4Z,7Z,10Z,13Z,16Z,19Z)), PS(P-16:0/17:2(9Z,12Z)), PS(22:0/22:1(11Z)), and PA(17:1(9Z)/0:0)) were significantly decreased, while two PA (16:0/18:2 (9Z, 12Z) and 16:0/18:1 (11Z)), two flavonoids (pelargonidin 3-(6''-malonylglucoside)-5-glucoside and malvidin 3-rutinoside) significantly increased in fruits of plants grafted onto Cucurbita maxima Duch. rootstocks. These metabolites were involved in the glycerophospholipid metabolic pathway, the mevalonate pathway, and the phenylpropanoid pathway. In summary, these results showed that the bitter fruits of grafted Balengcui were caused by Cucurbita maxima Duch. rootstocks. Phospholipids, cucurbitacins, and flavonoids were the key contributors for the occurrence of bitter fruits in Balengcui melon after grafting onto Cucurbita maxima Duch. rootstocks.

Radiotherapy is mainly a traditional treatment for breast cancer; however, the key genes and pathways in breast cancer associated with irradiation are not clear. In this study, we aimed to explore the messenger RNA expression changes between preradiation and postradiation breast cancer. The gene expression data set (GSE59733) was downloaded from Gene Expression Omnibus database. According to |log2FC (fold change) | ≥ 1 and with false discovery rate adjusted P value

Quorum sensing (QS) is a ubiquitous cell-cell communication mechanism in microbes that coordinates population-level cell behaviors, such as biofilm production, virulence, swarming motility, and bacterial persistence. Efforts to engineer QS systems to take part in metabolic network regulation represent a promising strategy for synthetic biology and pathway engineering. Recently, design, construction, and implementation of QS circuits for programmed control of bacterial phenotypes and metabolic pathways have gained much attention, but have not been reviewed recently. In this article, the architectural organizations and genetic contributions of the naturally occurring QS components to understand the mechanisms are summarized. Then, the most recent progress in application of QS toolkits to develop synthetic networks for novel cell behaviors creation and metabolic pathway engineering is highlighted. The current challenges in large-scale application of these QS circuits in synthetic biology and metabolic engineering fields are discussed and future perspectives for further engineering efforts are provided.

Conductive inks are applied widely in electromagnetic interference (EMI) shielding coating, but the heavy use of organic solvents may cause safety issues and environment pollution. We demonstrated the preparation of an eco-friendly conductive ink that is composed of silver flakes, waterborne polyurethane, and fluorocarbon surfactant (Capstone FS-30), with deionized water as solvent. The conductive ink can be drop-deposited easily on polyethylene terephthalate film to develop a highly efficient EMI shielding coating that achieves an ultrahigh EMI shielding effectiveness (EMI SE) of 74.5 dB at only 10 μm thickness. The shielding coating exhibits sufficient flexibility to ensure an EMI SE retention up to 96%, even after 5000 bending–releasing cycles (bending radius of 2 mm), which reveals an excellent EMI shielding reliability. The shielding coating also possesses a mechanical fastness under ultrasonic treatment and a chemical durability to various organic solvents. These impressive characteristics make our conductive ink attractive for effective electromagnetic protection, especially in high integrated equipment and devices.

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Satellite communications have recently been included as one of the enabling technologies for 5G backhauling, in particular for the delivery of bandwidth-demanding enhanced mobile broadband (eMBB) application data in 5G. In this paper we introduce a 5G-oriented network architecture empowered by satellite communications for supporting emerging mobile video delivery, which is investigated in the EU 5GPPP Phase 2 SaT5G Project. Two complementary use cases are introduced, including (1) the use of satellite links to support offline multicasting and caching of popular video content at 5G mobile edge, and (2) real-time prefetching of DASH (Dynamic Adaptive Streaming over HTTP) video segments by 5G mobile edge through satellite links. In both cases, the objective is to localize content objects close to consumers in order to achieve assured Quality of Experiences (QoE) in 5G content applications. In the latter case, in order to circumvent the large end-to-end propagation delay of satellite links, testbed based experiments have been carried out to identify specific prefetching policies to be enforced by the Multi-access computing server (MEC) for minimizing user perceived disruption during content consumption sessions.

Video applications using MPEG-DASH (Dynamic Adaptive Streaming over HTTP, such as YouTube and Netflix) have been dominating the Internet traffic in recent years. It is increasingly acknowledged that in order to provide video clients with better Quality-of-Experience (QoE), both content service providers and network operators need to be aware of clients' QoE in the first place. In this paper, we present a novel real-time QoE estimation system through edge computing, which has been implemented and deployed at a real LTE-A network edge. When equipped with such a system, any virtual network function (VNF) deployed in a mobile network will be able to infer all DASH clients' QoE under its coverage in real time, where no feedback from clients are needed. Furthermore, our scheme is able to work robustly in busy network environments involving air interface where packet errors frequently occur. The significance of such a scheme is the availability of accurate and real-time knowledge on user QoE through a very lightweight mechanism at the mobile edge, which can be instantaneously used for various content manipulation or resource adaptation operations in order to assure user QoE in dynamic conditions. Through experiments in a real LTE-A network, we demonstrate that our scheme is able to estimate DASH clients' QoE with very high accuracy with very low CPU and RAM footprint.

In this paper, four FRP-concrete composite slabs and one FRP profile without concrete slabs were tested through two types of shear connectors including FRP perfobond shear connectors and epoxy adhesive under positive and negative loads. For composite specimens under negative loads, flexural buckling failure was observed on the top flanges of FRP profiles; while shear buckling failure occurred on the webs of FRP profiles for those under positive loads. At the ultimate state, the measured mid-span deflection was more than 1/90 of the span for all specimens. Besides, it was noticed that relative slip at the interface between FRP profiles and concrete slabs for composite specimens with epoxy adhesive was lower than that for specimens with FRP perfobond shear connectors. Based on the Tsai-Wu criterion, the Tsai-Wu index of the two failure modes was calculated for composite slabs when buckling failure occurred.

This paper introduces the common ways for pepper decorticating and the current status of their applications and effects. According to the actual needs of market development and our analysis on peppers’ physical structures, three kinds of decorticating principles are put forward which include spiral, frictional and centrifugal decorticators and their mechanisms and advantages are analyzed in detail respectively, which will be highly instructive to the research of pepper decorticating equipment.

In an era of product homogeneity, the improvement of industrial design is an effective way for companies to gain a competitive advantage. Product style is one of the most important indices with which to evaluate the design of the product, and it has a significant impact on consumer satisfaction. However, it may also have less of an effect due to consumers’ familiarity with the product. Three measureable factors are examined in this paper to study how this arises: Product Involvement is used to measure consumers’ familiarity with a product, Product Emotion is used to measure consumers’ response to product style, and a Consumer Satisfaction Index is used to assess consumer satisfaction. The scale table was developed using smartphones; this empirical research involved 300 college students, with a questionnaire used to assess the regulatory role that product involvement plays in consumer satisfaction in response to product style. The results show that product style has a direct and positive effect on consumer satisfaction as well as a significant effect on the perceived quality and the expected quality of highly involved consumers’ satisfaction. However, it had only a slight effect on consumer satisfaction in cases of low involvement.

Irradiation exposure positive correlates with tumor formation, such as breast cancer and lung cancer. However, whether low dose irradiation induces hepatocarcinogenesis and the underlying mechanism remain poorly defined. In the present study, we reported that low dose irradiation facilitated the proliferation of hepatocyte through up-regulating HULC in vitro and in vivo. Low dose irradiation exposure elevated HULC expression level in hepatocyte. Deletion of heightened HULC erased the cells growth accelerated following low dose irradiation exposure. CDKN1, the neighbor gene of HULC, was down-regulated by overexpression of HULC following low dose irradiation exposure via complementary base pairing, resulting in promoting cell cycle process. Thus, our findings provide new insights into the mechanism of low dose irradiation-induced hepatocarcinogenesis through HULC/CDKN1 signaling, and shed light on the potential risk of low dose irradiation for the development of hepatocellular carcinoma in pre-clinical settings.

Internet video streaming applications have been demanding more bandwidth and higher video quality, especially with the advent of virtual reality and augmented reality appli-cations. While adaptive strea ming protocols like MPEG-DASH (dynamic adaptive streaming over HTTP) allows video quality to be flexibly adapted, e.g., degraded when mobile network condition deteriorates, this is not an option if the application itself requires guaranteed 4K quality at all time. On the other hand, conventional end-to-end transmission control protocol (TCP) has been struggling in supporting 4K video delivery across long-distance Internet paths containing both fixed and mobile network segments with heterogeneous characteristics. In this paper, we present a novel and practically feasible system architecture named MVP (mobile edge virtualization with adaptive prefetching), which enables content providers to embed their content intelligence as a virtual network function into the mobile network operator's infrastructure edge. Based on this architecture, we present a context-aware adaptive video prefetching scheme in order to achieve quality of experience (QoE)-assured 4K video on demand (VoD) delivery across the global Internet. Through experiments based on a real LTE-A network infrastructure, we demonstrate that our proposed scheme is able to achieve QoE-assured 4K VoD streaming, especially when the video source is located remotely in the public Internet, in which case none of the state-of-the-art solutions is able to support such an objective at global Internet scale.

Hydroxyl groups on the surface of ZnO films lead to the chemical decomposition of CH

With increased complexity of webpages nowadays, computation latency incurred by webpage processing during downloading operations has become a newly identified factor that may substantially affect user experiences in a mobile network. In order to tackle this issue, we propose a simple but effective transport-layer optimization technique which requires necessary context information dissemination from the mobile edge computing (MEC) server to user devices where such an algorithm is actually executed. The key novelty in this case is the mobile edge's knowledge about webpage content characteristics which is able to increase downloading throughput for user QoE enhancement. Our experiment results based on a real LTE-A test-bed show that, when the proportion of computation latency varies between 20% and 50% (which is typical for today's webpages), the downloading throughput can be improved up to 34.5%, with reduced downloading time by up to 25.1%

Plasma flow control is a new type of active flow control approach based on plasma pneumatic actuation. Dielectric barrier discharge (DBD) actuators have become a focus of international aerodynamic research. However, the practical applications of typical DBDs are largely restricted due to their limited discharge area and low relative-induced velocity. The further improvement of performance will be beneficial for engineering applications. In this paper, high-speed schlieren and high-speed particle image velocimetry (PIV) are employed to study the flow field induced by three kinds of plasma actuations in a static atmosphere, and the differences in induced flow field structure among typical DBD, extended DBD (EX-DBD), and tri-electrode sliding discharge (TED) are compared. The analyzing of the dynamic evolution of the maximum horizontal velocity over time, the velocity profile at a fixed horizontal position, and the momentum and body force in a control volume reveals that the induced velocity peak value and profile velocity height of EX-DBD are higher than those of the other two types of actuation, suggesting that EX-DBD actuation has the strongest temporal aerodynamic effect among the three types of actuations. The TED actuation not only can enlarge the plasma extension but also has the longest duration in the entire pulsed period and the greatest influence on the height and width of the airflow near the wall surface. Thus, the TED actuation has the ability to continuously influencing a larger three-dimensional space above the surface of the plasma actuator.

Alzheimer’s disease (hereinafter referred to as AD) has become a major global health problem for the elderly. Combining with the current computer-aided design system design for prevention and training of Alzheimer’s disease is one of the important ways to solve this problem. This study aims at the early subjective cognitive decline of Alzheimer’s disease (hereinafter referred to as SCD) . Through investigation and research, the behavior and psychological characteristics of SCD elderly are sorted out, and the main functions of cognitive training system are located. The main functions, interactions, colors and layout of the current cognitive system are summarized by analyzing the existing cognitive training system, and compared with the research results, a more reasonable system function, interaction mode, interface color and layout are determined. Therefore, the cognitive training system design strategy based on the behavioral and psychological characteristics of SCD elderly is summarized.

Adenosine-to-inosine (A-to-I) RNA editing is site-specific modification of RNAs that increases the diversity of the transcriptome and proteome. Most insects undergo complete metamorphosis, including four life cycle stages: egg, larva, pupa and adult. Many previous studies have confirmed that RNA-editing events occur in a development-specific manner; in other words, RNA-editing levels change during metamorphosis. Here, we describe an effort to identify the developmental specificity of RNA-editing events using a large-scale computational analysis of RNA-seq data derived from four developmental stages of the diamondback moth, Plutella xylostella. One thousand one hundred and eighty-seven A-to-I RNA-editing sites were predicted to be developmental stage specific (false-discovery rate

Existing pepper fruit peeling machine for peeling incomplete, improper peeling force, pit protective film damaged, lead to a high impurity rate, pit crushing, unsatisfactory color and other issues. In order to solve these problems, manufacturing pepper fruit preprocessing machine based on analysis of pepper machining process. The machine achieves pepper fruit surface damaged by differential principle, work in with pepper peeling machine to peel completely.

We present a first-principles density functional theory-based study about the impact of pressure on the structural and elastic properties of bulk CaN2, SrN2, and BaN2. Non-spin and spin polarized calculations indicate that the non-spin polarized ground state was more favourable with magnetic moments of 1.049 μB, 1.059 μB, and 1.014 μB for CaN2, SrN2, and BaN2, respectively, and these were in good agreement with previous experimental and theoretical data. The high bulk modulus of CaN2, SrN2, and BaN2 confirm that those compounds have low compressibility and high hardness. The obtained bulk modulus, N-N bond length, and optimized structure parameters are similar to those from previous studies.With an increase in applied pressure the independent elastic constants of CaN2, SrN2, and BaN2 indicated the presence of mechanical instability at 20, 15, and 10 GPa, which is possibly related to phase transitions in addition to a decrease in N-N bond length.

Spook has essential roles in the biogenesis of the molting hormone 20-hydroxyecdysone (20-E). The function of spook in the rice striped stem borer (SSB) Chilo suppressalis remains unclear, prompting our hypothesis that it exerts actions similar to those reported for other insect species. Here we amplified the full-length transcript of spook (Cs-Spook) in SSB by 5' and 3' rapid amplification of cDNA ends. Cs-Spook has conserved P450 motifs such as Helix-C, Helix-I, Helix-K, and PERF motif (PxxFxPxRF). It was highly expressed in late instar larvae but less so in newly molted larvae. Cs-Spook was highly expressed in prothoracic glands. Cs-Spook was knocked down by dsRNA treatments. Compared with controls, the gene expression level was reduced to 9% at 24 h post injection (PI), 33% at 48 h PI, and 24% at 72 h PI. The ecdysteroid titer decreased significantly in the dsRNA-treated group (P < 0.05), resulting in delayed larval development. The delayed development in dsRNA-treatment group was rescued by treating with 20-E. Our work demonstrates that Cs-Spook participates in the biogenesis of 20-E and regulates the molt of SSB, as seen in other species.

In a content delivery network (CDN), the energy cost is dominated by its geographically distributed data centers (DCs). Generally within a DC, the energy consumption is dominated by its server infrastructure and cooling system, with each contributing approximately half. However, existing research work has been addressing energy efficiency on these two sides separately. In this paper, we jointly optimize the energy consumption of both server infrastructures and cooling systems in a holistic manner. Such an objective is achieved through both strategies of: 1) putting idle servers to sleep within individual DCs; and 2) shutting down idle DCs entirely during off-peak hours. Based on these strategies, we develop a heuristic algorithm, which concentrates user request resolution to fewer DCs, so that some DCs may become completely idle and hence have the opportunity to be shut down to reduce their cooling energy consumption. Meanwhile, QoS constraints are respected in the algorithm to assure service availability and end-to-end delay. Through simulations under realistic scenarios, our algorithm is able to achieve an energy-saving gain of up to 62.1% over an existing CDN energy-saving scheme. This result is bound to be near-optimal by our theoretically-derived lower bound on energy-saving performance.

Porous calcium phosphate (CaP) ceramics are widely used in bone tissue engineering due to their excellent biological properties. However, the inherent brittleness of CaP ceramics has restricted their applications in the repair of load-bearing bones. This study aimed to improve the mechanical strength of CaP-based scaffolds by compositing CaP with collagen (Col). In this study, the influences of CaP porous structure, collagen content and cross-linking method on scaffolds mechanical strength were investigated. The morphologies of the composites were characterized by scanning electron microscope, and the mechanical properties of the scaffolds were assessed by dynamic mechanical analysis. The biocompatibility of the scaffolds was evaluated by culturing human bone marrow mesenchymal stem cells (MSCs) in vitro . The results show that the mechanical properties of scaffolds can be significantly improved by optimizing composite processes. Furthermore, remarkable viability and proliferation of MSCs on scaffolds was observed, which demonstrated good biocompatibility of the scaffolds. These results suggest that CaP/Col composite can be a promising scaffold for repair of load-bearing bones.

A stretchable, low-voltage, and deformation-stable heater was fabricated via a simple, efficient, and scalable process. Such heater integrates thermoplastic polyurethane (TPU) with segregated carbon nanotube (CNT) networks, exhibiting a high electrical conductivity of 142.6 S m−1 and the steady-state maximum temperature (TMAX) of 65 °C at only 6 V. The CNT/TPU heater maintains excellent temperature reliability during the heating-cooling stepwise cyclic operation. The attached tests to hand and wrist further prove the effective heat transfer and the compatibility of the CNT/TPU heater with the human skin. Moreover, 86% TMAX retention is achieved even when the heater undergoing 20% tensile strain and the TMAX could return to the original value once the strain released. The availability and reliability of our CNT/TPU heater under complex conditions demonstrate potential applications in next-generation wearable devices for human heating systems.