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Acidosis, regardless of hypoxia involvement, is recognized as a chronic and harsh tumor microenvironment (TME) that educates malignant cells to thrive and metastasize. Although overwhelming evidence supports an acidic environment as a driver or ubiquitous hallmark of cancer progression, the unrevealed core mechanisms underlying the direct effect of acidification on tumorigenesis have hindered the discovery of novel therapeutic targets and clinical therapy. Here, chemical-induced and transgenic mouse models for colon, liver and lung cancer were established, respectively. miR-7 and TGF-β2 expressions were examined in clinical tissues (n = 184). RNA-seq, miRNA-seq, proteomics, biosynthesis analyses and functional studies were performed to validate the mechanisms involved in the acidic TME-induced lung cancer metastasis. Our data show that lung cancer is sensitive to the increased acidification of TME, and acidic TME-induced lung cancer metastasis via inhibition of miR-7-5p. TGF-β2 is a direct target of miR-7-5p. The reduced expression of miR-7-5p subsequently increases the expression of TGF-β2 which enhances the metastatic potential of the lung cancer. Indeed, overexpression of miR-7-5p reduces the acidic pH-enhanced lung cancer metastasis. Furthermore, the human lung tumor samples also show a reduced miR-7-5p expression but an elevated level of activated TGF-β2; the expressions of both miR-7-5p and TGF-β2 are correlated with patients’ survival. We are the first to identify the role of the miR-7/TGF-β2 axis in acidic pH-enhanced lung cancer metastasis. Our study not only delineates how acidification directly affects tumorigenesis, but also suggests miR-7 is a novel reliable biomarker for acidic TME and a novel therapeutic target for non-small cell lung cancer (NSCLC) treatment. Our study opens an avenue to explore the pH-sensitive subcellular components as novel therapeutic targets for cancer treatment.

Although targeting DNA repair signaling pathways has emerged as a promising therapeutic for skin cancer, the relevance of DNA damage responses (DDR) in the development and survival of nonmelanoma skin cancer (NMSC), the most common type of skin cancer, remains obscure. Here, we report that Src‐associated substrate during mitosis of 68 kDa (Sam68), an early signaling molecule in DDR, is elevated in skin tumor tissues derived from NMSC patients and skin lesions from Gli2‐transgenic mice. Downregulation of Sam68 impacts the growth and survival of human tumor keratinocytes and genetic ablation of Sam68 delays the onset of basal cell carcinomas (BCC) in Gli2‐transgenic mice. Moreover, Sam68 plays a critical role in DNA damage‐induced DNA repair and nuclear factor kappa B (NF‐κB) signaling pathways in keratinocytes, hence conferring keratinocyte sensitivity to DNA damaging agents. Together, our data reveal a novel function of Sam68 in regulating DDR in keratinocytes that is crucial for the growth and survival of NMSC., Here, we report that Sam68, an early signaling molecule in DDR, is elevated in skin tumor tissues derived from NMSC patients and skin lesions from Gli2‐transgenic mice. Downregulation of Sam68 impacts the growth and survival of human tumor keratinocytes and genetic ablation of Sam68 delays the onset of basal cell carcinomas (BCC) in Gli2‐transgenic mice. Moreover, Sam68 plays a critical role in DNA damage‐induced DNA repair and nuclear factor kappa B (NF‐κB) signaling pathways in keratinocytes, hence conferring keratinocyte sensitivity to DNA damaging agents.

H- and Nb-doped ZnO (HNZO) thin films were fabricated on glass substrates with radio frequency magnetron sputtering. The effect of the flow rate of H2 has been investigated by analyzing the structural, optical, and electrical properties. The incorporation of H during the deposition of Nb-incorporated ZnO films significantly improved their crystallinity, conductivity, and transmittance. The crystallites of the HNZO films were preferentially oriented in the c-axis direction; the films possess high transmittance (approximately 85%) in the visible and near-infrared regions (400 to 1400 nm). The lowest room-temperature resistivity of the HNZO films was measured as 1.28 × 10−3 Ω cm. Such optical and electrical properties along with the remarkable chemical stability of the HNZO films make them a promising candidate for applications in solar cells.

The annual sea surface temperature increased at a rate of 0.038 to 0.074 °C/year in recent decade, and pH decreased at a rate of 0.012–0.014/year in two coastal waters of the South China Sea. Therefore, a culture experiment was conducted to study the effects of acidification and warming on coral calcification rates. The calcification of three coral species were significantly reduced during the exposure to elevated CO2, while other three coral species were not significantly affected. The reef coral Pocillopora damicornis was resistant to high CO2, but was not able to survive during the exposure to 33 °C in our culture experiments. Our findings suggested that some corals might not survive in tropical areas if coral could not adapt to warming rapidly, and subtropical coastal waters with temperature of

The development of society requires high-quality talents, which propels colleges and universities to cultivate graduates with both theoretical and practical abilities. As an applied undergraduate university, Beijing City University has always attached importance to cultivating students' practical ability based on theoretical teaching. In “Project Planning and Control”, a module for the major of project management, the task-driven method is used for practical training. The college aims to improve students' ability to apply the theory through practical training scenarios, real-life training tasks, assessments and other key steps. In order to test the effect of practical training, SPSS statistical software is used to perform paired sample T test and correlation analysis on the usual scores and final scores. The analysis results show that the design of practical training is reasonable, achieving good results.

In today’s Internet era, “blended learning” is a relatively advanced and effective learning method, which is of great significance for promoting curriculum teaching reforms and improving teaching quality. This paper explores the blended teaching design method of the platform course of “Management”, clarifies the teaching objectives, overall design and unit design, and implements in teaching. A comprehensive evaluation of the teaching effect was made in three areas of the usage of the platform, analysis of students’ assessment grades and feedback of students’ questionnaire, which shows that blended teaching has achieved good results. There are still some problems in the implementation of blended teaching, including the quantity and quality of teaching resources, as well as the students’ assessment results need to be improved, and need to be improved in future research.

In this paper, novel micro- and nano-composite Al-doped ZnO (AZO) films with broadband-gap light-trapping capacity was successfully fabricated by post-chemical-etching AZO film and re-sputtering self-textured H and Al co-doped ZnO (HAZO) film. The influence of pressure and etching time on the optical and electrical properties of HAZO, AZO, and AZO/HAZO films were systematically investigated. The performance of this novel ZnO film was increased remarkably compared to that of the post-etched AZO film or native textured HAZO film for both long and short wavelengths. Microcrystalline silicon solar cells deposited on this new type of AZO/HAZO films exhibited a strong enhancement of 13.4% in the conversion efficiency, demonstrating its wide application prospect.

Power distribution faulting is one of the main reasons for the unplanned outage. In terms of the distribution fault outage, cost evaluation and hotspot area recognition are beneficial for utilities to develop schemes tailored for distribution operation, maintenance and upgrading. In this study, multi-source data from marketing, distribution, and dispatching fields are effectively utilised for comprehensive information collection of medium-voltage distribution network faults. A new approach to fault fuzzy location is proposed using distribution network topology and transformer outage duration. Meanwhile, fault outage cost is evaluated based on the short-term load forecast of distribution transformers, which completely considers the impact of load transferring on multi-power supply users. Furthermore, the distribution blackout events are mapped with geography information system, and the fault hotspot areas are highlighted by geographical grid virtualisation. The method proposed in this study has been validated using practical examples. This approach has been actually applied in Jiangsu distribution maintenance management.

This paper presents a suitability evaluation approach to assess whether the LTE-based wireless private network satisfies the communication needs of smart grid applications. This approach can obtain different evaluation indexes including reliability, delay and throughput when the business attributes are used as the initial inputs by analyzing the MAC and PHY layer models and coverage characteristics. Then combined with the business analysis model, the applicability of wireless private network can be evaluated according to different power business needs. In order to verify the use of the proposed evaluation method, a simulation analysis of the suitability of the LTE 1.8GHz wireless private network is conducted for the businesses of power distribution and utilization.

On the foundation of the original backpressure-based traffic light control algorithm, a distributed cooperative backpressure-based traffic light control method is proposed in this paper. The urban traffic network is modeled as a smart agent-controlled queuing network, in which the intersection agents exchange the queue length information and the selected activating light phase information of neighboring intersections through communications and determine the activating light phase at each time slot according to local traffic information. The improved phase pressure computation method considers the phase state of downstream intersections instead of only the queue length of the local intersections. Light phase switching coordination among adjacent intersections is achieved using the consensus-based bundle algorithm, in which the cooperative light phase switching problem is viewed as a task assignment issue among adjacent intersections. Simulation results illustrated that the proposed cooperative backpressure-based traffic light control method obtained better performance than the original backpressure-based and fixed-time traffic control methods.

It has been shown that the deployment of device-to-device (D2D) communication in cellular systems can provide better support for local services. However, improper design of the hybrid system may cause severe interference between cellular and D2D links. In this paper, we consider transceiver design for the system employing multiple antennas to mitigate the interference. The precoder and decoder matrices are optimized in terms of sum mean squared error (MSE) and capacity, respectively. For the MSE minimization problem, we present an alternative transceiver optimization algorithm. While for the non-convex capacity maximization problem, we decompose the primal problem into a sequence of standard convex quadratic programs for efficient optimization. The evaluation of our proposed algorithms for performance enhancement of the entire D2D integrated cellular system is carried out through simulations.

Highly transparent conductive F and Ga co-doped ZnO films were deposited on a glass substrate with radio frequency magnetron sputtering at various growth temperatures. Growing the films at a substrate temperature of 480 °C produced the lowest resistivity of 6.84 × 10−4 Ωcm, a carrier concentration of 2.3 × 1020 cm−3, and a mobility of 39.7 cm2/Vs. These parameters were significantly improved to 3.53 × 10−4 Ωcm, 3.08 × 1020 cm−3, and 57.5 cm2/Vs, respectively, after a rapid thermal annealing treatment. All the films showed a high average transmittance of 90% in the optical range 380–1400 nm.

The customized wireless devices play a key role in information exchanging for various electrical facilities. However, the development of the devices is hindered by diversity of interfaces (RS-232/485, Ethernet, USB, etc.), high cost, outdoor environment, etc. In this work, we proposed a ‘system on module’ solution to address above issues. We optimize and spare the storage space of baseband chip for embedded control system to replace the independent chips, which dramatically reduces the size, cost and power consumption of devices. Meanwhile, our SOM wireless devices can support multi-interfaces and thus realize ‘plug and play’. Moreover, our developed wireless devices allow multimode wireless communications including operator's wireless networks LTE FDD/TDD, UMTS, GSM and self-built LTE-G 1800MHz network. Last but not least, we can embedded positioning chip and the client of management system in the wireless devices for the sake of operation and maintenance.

In view of all kinds of network attacks which may affect the network security of the smart grid system, an attack detection algorithm is proposed, feature extraction and training to the data such as server logs is carried out based on Hidden Markov model (HMM) to achieve the network attack detection in smart grid system. By the proposed algorithm, analysis on real data of the smart grid system in one power company is carried out, which can effectively identify common types and numbers of network attack types. Through the proposed smart grid network attack detection algorithm, network security risks in the smart grid system can be found, and the level of network security is improved.

Distribution Fault outage directly influences the normal electricity consumption. Accurate evaluation of distribution fault outage cost plays a key role in the investment and decision on improving the power supply reliability. Based on distribution topology, we first analyze the characteristics of distribution load when take distributed photovoltaic generation (DPG) into accounts and propose the practical load models for both power generation and consumption of DPG with big data approach. Finally, we calculate the load and economic loss of all the distribution transformers and the overall outage cost in the perspective of feeder line as well. The numerical results present the effectiveness of our method.

PWM control method is an important method for the optimization operation of Dual Active Bridge (DAB) converter. The traditional way which is used to analyze PWM control is not precise and comprehensive. This paper gives the accurate calculation of power flow and RMS value of inductor current by proposing a novel method. Six modes are analyzed based on the control signal distributions. Finally, the simulations and experiments are used to verify the theoretic results.

This paper presents an improved direct torque control (DTC) method for the wind power generation system based on the doubly-fed induction generator (DFIG). The basic principle of direct torque control based on DFIG system is analyzed. An improved strategy is presented by increasing the division accuracy of rotor flux position and the number of basic voltage vectors. The proposed method improves the performances of the system and reduces the rotor and torque ripples. By comparing the simulation results of the conventional and the improved DTC method applied in DFIG-based wind power generation system, the effectiveness of the proposed control method is validated.

Traditional strategy about the fault diagnosis always puts all thoughts on the identification of the fault location and its accuracy. Few systems associate the fault with the cause of fault occurring. This paper presents a structure of the fault diagnosis system aided for the power system operating, which diagnoses whether the lightning strokes the fault or the surrounding circumstances affect the grid operation. The system structure not only has extensibility for the intelligent algorithms, but also meets the requirements of information security. Validation demonstrates that the system with the environment monitoring is effective for the fault diagnosis and analysis.

The parameter determination of viscoelastic material is a multi-variable, multi-aim nonlinear optimization problem, which made the optimization process very complicated. In this paper a hybrid optimal algorithm was proposed to determine the viscoelastic parameters in the constitutive relation according to the experimentally obtained mechanical properties. This algorithm merges the Broydon–Fletcher–Goldfarb–Shanno search into a genetic algorithm framework as a basic operator in order to enhance the local search capability. The proposed hybrid algorithm not only can reduce the iterative times greatly but can abolish the limitation of initial parameter values. Nonlinear material characteristic curve-fitting was carried out using the proposed algorithm and other existing approaches. And the comparison results show this algorithm is accurate and effective. The numerical simulation and experimental study of viscoelastic cantilever beam also indicates that the finite element formulation and the calculative viscoelastic model parameters are reliable. The proposed optimization method can be extended to further complex parameter estimation researches.

In a vehicular ad hoc network (VANET), the periodic exchange of single-hop status information broadcasts (beacon frames) produces channel loading, which causes channel congestion and induces information conflict problems. To guarantee fairness in beacon transmissions from each node and maximum network connectivity, adjustment of the beacon transmission power is an effective method for reducing and preventing channel congestion. In this study, the primary factors that influence wireless channel loading are selected to construct the KF-BCLF, which is a channel load forecasting algorithm based on a recursive Kalman filter and employs multiple regression equation. By pre-adjusting the transmission power based on the forecasted channel load, the channel load was kept within a predefined range; therefore, channel congestion was prevented. Based on this method, the CLF-BTPC, which is a transmission power control algorithm, is proposed. To verify KF-BCLF algorithm, a traffic survey method that involved the collection of floating car data along a major traffic road in Changchun City is employed. By comparing this forecast with the measured channel loads, the proposed KF-BCLF algorithm was proven to be effective. In addition, the CLF-BTPC algorithm is verified by simulating a section of eight-lane highway and a signal-controlled urban intersection. The results of the two verification process indicate that this distributed CLF-BTPC algorithm can effectively control channel load, prevent channel congestion, and enhance the stability and robustness of wireless beacon transmission in a vehicular network.

Applying of network security situation awareness in smart substations provides a high level view to understand the security situation of substations. After analyzing security threats faced by smart substations, this paper not only proposes a security situation awareness framework from aspects of physical security, network security, system security, protocol security and data security, but also puts forward a network security monitoring solution for substations, which uses a kind of dedicated smart substation network security situation awareness devices to collect security events, analyze them and generate situation analysis results. Further, we focus on several key technologies used in our framework. Finally, we describe a design scheme including hardware and software for the smart substation network security awareness system and its implementation architecture, in which a multi-layer software architecture is adopted by the system, and a combinatory of the Intel® Sandy Bridge, the bus structure and a modular design technology, is adopted in order to meet the need of high performance.

In order to solve the problem of excessive temperature in the discharge process of lithium-ion battery and the temperature difference between batteries, a heat dissipation of electric vehicle based on safety architecture optimization is designed. The simulation is used to optimize the temperature field of the heat dissipation of the battery. A reasonable heat dissipation control scheme is formulated to achieve heat dissipation requirements. The results show that the ideal working temperature range of the lithium ion battery is 20?~45?, and the temperature difference between the batteries should be controlled within 5?. A cooling fan is arranged at the original air outlet of the battery model, and the two cooling fans work in turn to realize the reciprocating flow. The temperature difference is controlled within 5? to ensure the good temperature uniformity between the batteries of the electric vehicle. Based on the above finding, it is concluded that the heat dissipation design for electric vehicle batteries is safe and effective, which is the most effective methods to ensure battery life and vehicle safety.

Aiming to reduce the computation and implement compliant control, this paper proposes a novel inverse dynamics control strategy based on the floating-base rigid body system. The control strategy assumes that each leg of the quadruped robot organizes itself into an independent autonomous system, a serial robot. Based on this assumption, the kinematics and the dynamics models of the quadruped robot have been created. The dynamical model supposes two different models according to the leg's state. In the stance phase the serial robot affixes its base frame to the shank and iterates the rigid body dynamics algorithms from the knee joint to the body. When the serial robot is in the swing phase, the dynamics algorithm is propagated from the hip joint to the shank, whose computing direction is just the reverse against the direction of which the serial robot is in the stance phase. The quadruped system doesn't need the fixed base to the system and avoids calculating the virtual joints of 6-DOF. Therefore, the algorithm proposed in this paper makes real-time computation of the quadruped robot dynamics possible. In order to evaluate the efficiency of the inverse dynamical control strategy, experiments are accomplished based on a practical quadruped robot. The experiments, which were done on a rubber mat and on asphalt, demonstrated that the quadruped robot is able to walk adaptively.

Objectives Pulmonary vascular remodelling is an important pathologic feature of Pulmonary hypertension (PH). Pulmonary arterial smooth muscle cells (PASMCs) increased proliferation is an important component of pulmonary vascular remodelling. Regulation of PASMCs proliferation may therefore be critical to pulmonary vascular remodelling in PH, however the underlie mechanisms are still controversial. However, the precise mechanism of PH still remains to be elucidated. Changes to Ca 2+ -activated potassium channels (KCa) in proliferating vascular smooth muscle cells (VSMCs) have been described, but no regulatory role in proliferation has been attributed to them. KCa channels as a bridge between Ca 2+ signal and electrical activation in excitable cells, including of PASMCs, became more and more popular in research of hypertension, PH and atherosclerosis. Intermediate conductance calcium-activated potassium channel (IKCa) and large conductance calcium-activated potassium channel (BKCa) are two subtypes of KCa family. In systemic circulation VSMCs, BKCa channel expression defines the contractile phenotype of VSMCs, while expression of IKCa channels characterises proliferating cells. The role of IKCa channel in PASMCs proliferation is unclear. Rho/Rho kinase signalling pathway plays an important role in various cellular functions which involved in the pathogenesis of PH. Rho/Rho kinase signalling pathway mediates vascular smooth muscle cell contraction and vasoconstriction, the signalling pathway mediates ‘Ca 2+ sensitisation’ of spontaneous. The upstream signals responsible for activation of Rho/Rho kinase signalling in PH is not is unclear. To investigate expression change of KCa channel and Rho/Rho kinase signalling pathway in ET-1 induced proliferation of pulmonary arterial smooth muscle cells and to investigate modulation mechanism. Methods The primary human PASMCs in 5–10 generations were cultured in 37°C with 5% CO 2 and incubated with several concentration of ET-1 (0, 10, 100 nmol/l), or co-cultured with ET-1 (10 nmol/l) pretreated with Clotrimazole (10 µmol/l, IKCa inhibitor), Fasudil (100 nmol/l, Rho kinase inhibitor) or Bosentan (100 nmol/l, inhibitor) respectively for 24 h. After the PASMCs were harvested, we used real time RT-PCR and western blot analysis to evaluate the expression and characteristics of IKCa channels and RhoA. We also used the MTT analysis and flow cytometric analysis to investigate the effects of IKCa channels on cell proliferation and the mechanisms involved. Results High concentration ET-1 induced cell proliferation in human PASMCs in a dose- dependent manner. The IKCa channels expression of mRNA and protein is up-regulated in ET-1 induced proliferation of human PASMCs in a dose-dependent manner. The RhoA expression of mRNA and protein is up-regulated in ET-1 induced proliferation of human PASMCs in a dose-dependent manner. Inhibition of IKCa prevents ET-1 induced proliferation of human PASMCs. Inhibition of Rho/Rho kinase signalling pathway prevents ET-1 induced proliferation of PASMCs. BKCa channel inhibition fails to prevent ET-1 induced PASMCs proliferation. Inhibition of Rho/Rho kinase signalling pathway prevents up-regulated change of IKCa channel express in ET-1 induced PASMCs proliferation. ET-1 induced cell proliferation model in human PASMCs is a simple and useful cell proliferation model for basic research of PH. Conclusions There are an up-regulated change of IKCa channels expression and RhoA expression in ET-1 induced proliferation of human PASMCs. There are an ion channel remodelling of KCa channels, which including up-regulated change of IKCa channels expression and down-regulated change of BKCa channels expression in ET-1 induced proliferation of PASMC. IKCa channel inhibition prevents PASMCs proliferation, Rho/Rho kinase signalling pathway may be involved in partially. IKCa channels and Rho/Rho kinase signalling pathway are important in PASMCs cell proliferation, making the channel and the signalling pathway a potential therapeutic target in pulmonary vascular remodelling.