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Radiation cooling, as a new terminal mode that has been gradually emerging in recent years, has attracted more and more attention. However, the problem of condensation has become a vital bottleneck restricting the broad application of radiation-cooling technology. This paper used the numerical simulation method of Ansys Fluent to study the effect of different water supply parameters on the concrete radiant roof’s heat transfer performance, temperature uniformity analysis, and anti-condensation temperature control strategy. The accuracy of the simulation model was verified by comparing the numerical simulation values and measured values of temperature monitoring points. In thermal performance research, the inlet temperature significantly impacted the cooling capacity and radiant surface temperature compared with the inlet flow velocity. In the uniformity study, the distance between the serpentine pipes area and the concrete edge was easily neglected, which was also an important factor affecting the distribution of temperature uniformity. Regarding anti-condensation and performance improvement research, first supplying water at low temperatures and then dynamically adjusting high-temperature water could effectively avoid condensation and improve the radiant roof’s heat transfer performance. The research results could provide technical references for the practical application of radiation roof anti-condensation temperature control technology.

As the leading cause of cancer-related death worldwide, non-small-cell lung cancer (NSCLC) is still in need of improved therapeutic strategies. CircKIF4A has been found to be involved in the progression of multiple cancers while its role in NSCLC remains unclear. To investigate the functions of circKIF4A, we assessed the expression of circKIF4A in NSCLC cells and tissues and performed experiments to determine the detailed functions of circKIF4A in NSCLC, including migration and proliferation. We found CircKIF4A expressed more heavily in the cells and tissues of NSCLC patients, and functional studies showed that inhibition of circKIF4A reduced NSCLC cells metastasis and proliferation. Furthermore, we seek to identify the underlying regulatory effect of circKIF4A in NSCLC. Studies revealed that circKIF4A sponged miR-1238 to promote NSCLC progression by up-regulating claudin14 (CLDN14) expression. In conclusion, circKIF4A is a potential diagnostic and therapeutic target in the circKIF4A/miR-1238/CLDN14 axis that plays an important role in NSCLC progression.

Synchronization in complex networks has been investigated for decades. Due to the particularity of the interlinks between networks, the synchronization in interdependent networks has received increasing interest. Since the interlinks are not always symmetric in interdependent networks, we focus on the synchronization in unidirectional interdependent networks to study the control scheme. The mathematical model is put forward and some factors are taken into consideration, such as different coupling functions and strengths. Firstly, the feasibility of the control scheme is proved theoretically by using Lyapunov stability theory and verified by simulations. Then, we find that the synchronization could be maintained in one sub-network by utilizing our control scheme while the nodes in the other sub-network are in chaos. The result indicates that the influence of interlinks can be decreased and the proposed scheme can guarantee the synchronization in one sub-network at least. Moreover, we also discuss the robust of our control scheme against the cascading failure. The scheme is verified by simulations to be effective while the disturbances occur.

Sulfonic acid modified organic hyper-cross-linked polymer (HCP) based carbocatalyst with variable –SO3H density and porosity, was synthesized for the one-pot conversion of biomass derived carbohydrates into potential fuel candidate 5-ethoxymethylfurfural (EMF). The structural characterizations revealed that the porous structure of HCP was well maintained after sulfonation process, thus rendering good structure and high Brϕnsted acid density for the one-pot dehydrative etherification reaction. The as-prepared HCP materials exhibited promising catalytic performance for ketoses conversion, which yielded 78.9% of EMF along with 15.4% 5-hydroxymethylfurfural (HMF) and 4.6% ethyl levulinate (EL) using fructose as starting material in ethanol-DMSO biphasic system. Meanwhile, considerable increase in EMF yield from glucose based carbohydrates was attained when adding slight amounts of Lewis acid AlCl3 to reaction protocol. The HCP based catalyst was able to be reused several times without significant loss in catalytic activity. More importantly, the HCP materials were also highly active in other related acid-catalyzed reactions, including esterification, transesterification and dehydration.

A confined MnO2 catalyst with MnO2 nanoparticles entrapped in TiO2 nanotube was synthesized through vacuum-assisted impregnation method. Due to the confinement effect of TiO2 nanotube, the electron density distribution between the exterior and interior nanotube surface is modulated. As such, the confined MnO2 can facilitate the formation and migration of active oxygen species in the catalyst. The catalyst exhibits the enhanced activity in the catalytic combustion of butane, and the reaction temperature is significantly lowered. This result demonstrates that the confined MnO2 in TiO2 nanotube can serve as a cost-effective catalyst for the elimination of VOCs from the air.

To enhance the heat and mass transfer during dimethyl ether (DME) steam reforming, a micro-reactor with catalyst coated on nickel foam support was designed and fabricated. A two-dimensional numerical model with SIMPLE algorithm and finite volume method was used to investigate 1) the fluid flow, 2) the heat transfer and 3) chemical reactions consist of DME hydrolysis, methanol steam reforming, methanol decomposition and water gas shift reactions. Both the numerical and the experimental results showed that the DME conversion in the micro-reactor is higher than that in the fixed bed reactor. The numerical study also showed that the velocity and the temperature distribution were more uniform in the micro-reactor. Wall temperature, porosity and steam/DME ratio have been investigated in order to optimize the process in the micro-reactor. The wall temperature of 270 °C and the steam/DME feed ratio of 5 were recommended. Meanwhile the results indicate that a larger porosity will give a higher DME conversion and CO concentration.

Preferential oxidation of CO (CO-PrOx) is an important step to meet the need of the proton exchange membrane (PEM) fuel cell without the Pt anion poison. A glycine-nitrate approach was used for the synthesis of Co/CeO2 nanoparticle for preferential oxidation of CO, which a precursor solution was prepared by mixing glycine with an aqueous solution of blended nitrate in stoichiometric ratio. Then the glycine-mixed precursor solution was heated in a beaker for producing nanosized porous powders. Catalytic properties of the powders were investigated and results illustrate that the Co-loading of 30 wt.% catalysts exhibits excellent catalytic properties. Various characterization techniques like X-ray diffraction, SEM, BET, Raman and TPR were used to analyze the relationship between catalyst nature and catalytic performance. The X-ray diffraction patterns and SEM micrographs indicate that catalysts prepared by glycine-nitrate combustion own mesopore structure. The BET, Raman and TPR results showed that the high activity of the 30 wt.% Co-loading of Co/CeO2 catalysts is related to the high BET surface and the strongly interaction between fine-dispersed Co species and CeO2 support.

The present study used an in vitro model of cold cardioplegia in isolated working rat hearts to evaluate the possible role of ethyl pyruvate (EP) in promoting cardiac function and preventing apoptosis. Two groups of rats were evaluated; the EP (2 mM EP; n=8) and control (n=8) groups. Isolated rat hearts were perfused with Krebs-Henseleit buffer (KHB) for 30 min, arrested with cardioplegic solution and stored for 4 h in B21 solution at 4°C. The hearts were reperfused with KHB for 45 min. EP was added to the cardioplegic and storage solutions and also to KHB for reperfusion. Cardiac parameters of the heart rate, including left ventricular systolic pressure, left ventricular end-diastolic pressure, left ventricular developed pressure and maximal rise rate of the left ventricular pressure, were monitored. In addition, coronary flow, adenosine triphosphate (ATP) levels and malondialdehyde (MDA) content were recorded and apoptotic cell determination was detected. The functional parameters in the EP group were significantly higher compared with those in the control group during the reperfusion period (P

This study aimed to determine the effect of andrographolide (AD) on the growth of H3255 lung cancer cells and its possible impact on the expression and activity of the matrix metalloproteinase (MMP)-9 protein. H3255 cells were cultured in vitro, and treated with AD (1, 5 or 10 μM) for 24, 48 or 72 h. Cell proliferation was detected using an MTT assay and the expression of MMP-9 mRNA was measured using a reverse transcription-polymerase chain reaction (RT-PCR). The activity of MMP-9 was assessed by gelatin zymography, while the nuclear translocation of the nuclear factor-κB (NF-κB) p65 subunit and the phosphorylation of IκB were determined by western blotting. AD inhibited the proliferation of the H3255 cells in a concentration- and time-dependent manner, in addition to downregulating the expression of MMP-9 mRNA and the activity of MMP-9. Moreover, AD significantly inhibited the nuclear translocation of the NF-κB p65 subunit and suppressed IκB phosphorylation. The significant inhibition of H3255 cell proliferation by AD may have been correlated with the reduction in MMP-9 expression and activity through the inhibition of the phosphorylation of IκB and the translocation of NF-κB. The results suggest that AD is a promising drug candidate for the treatment of the migration and invasion of malignant tumors.

Hydrogen production from catalytic steam reforming of model compound acetic acid of bio-oil was investigated under atmospheric pressure in a bench-scale fixed-bed reactor and a series of Ni catalysts supported on ceria–zirconia were prepared via co-precipitation with varying contents of Ni and Ce loading. Simultaneously, effects of reaction temperature, and molar ratio of steam to carbon fed, liquid hourly space velocity (LHSV) were also explored. The results indicated that the 12Ni/7.5Ce-Zr-O catalyst was superior to other catalysts with different Ni and Ce loading. At T = 650 °C, S / C = 3, LHSV = 2.8 h −1 , the reaction over Ni catalyst supported on ceria–zirconia turns out that the highest activity and the maximum hydrogen selectivity of 83.4% and the minimum methane selectivity of 0.39% are attained. Besides, Ni catalyst supported on ceria–zirconia shows good stability during 25 h continuous reaction without any deactivation.

In order to develop alloys combing high hydrogen permeability with large resistance to the hydrogen embrittlement, microstructures and hydrogen permeability ( Φ ) have been investigated for the as-cast alloys on the straight line connecting the eutectic {TiCo + (Nb, Ti)} phase and the Nb-rich primary (Nb, Ti) phase in the Nb–Ti–Co system. The alloys on the above-mentioned line consist of the TiCo compound and the (Nb, Ti) solid solution. The value of Φ increases with increasing temperature and volume fraction of the primary (Nb, Ti) phase. The most Nb-rich Nb 60 Ti 21 Co 19 alloy shows the highest Φ value of 3.99 × 10 −8 (mol H 2 m −1 s −1 Pa −0.5 ) at 673 K, which is 2.6 times higher than that of pure Pd. The present work demonstrates that highly hydrogen permeable alloys are obtainable in the Nb rich Nb–Ti–Co ones on the straight line connecting the eutectic {TiCo + (Nb, Ti)} phase and the Nb-rich primary (Nb, Ti) phase.

This study was to investigate the effects of Rosa laevigata Michx. (RLM) extract on reactive oxygen species (ROS) production and mitochondrial membrane potential (MMP) in lens epithelial cells (LECs) cultured under high glucose. SRA01/04 cell models of diabetic cataract were established by high glucose culture, and these cells were administrated with RLM extract. Levels of ROS and MMP in SRA01/04 cells were detected with fluorescent probes. HO-1 expression level, Akt phosphorylation, and Nrf2 translocation were detected by Western blot. RLM treatment could exert protective effects on SRA01/04 cells under high glucose condition, decreasing the ROS production and elevating the MMP in these cells. Western blot analysis indicated that the expression level of HO-1 was significantly elevated in SRA01/04 cells after the RLM treatment. Moreover, when HO-1 was interfered with siRNA, the effects of RLM on the levels of ROS and MMP were diminished, indicating that HO-1 induction was necessary for the function of RLM. Furthermore, HO-1 inducing effects of RLM were mediated by the PI3K/Akt and Nrf2/ARE pathways. The effects would be abolished when either pathway was inhibited by pharmacological manipulation or siRNA silencing. RLM inhibits ROS production and elevates MMP, through the induction of HO-1 expression, in LECs under high glucose condition. The protective effects of RLM are mediated by the PI3K/Akt and Nrf2/ARE pathways. Our findings provide theoretic basis and experimental evidence for the application of RLM in the treatment of diabetic cataract.

Previously, there were no data looking at the quality evaluation of randomized controlled trials (RCTs) on effect comparison of laparoscopic surgery and open surgery for colorectal cancer in China. Here, we evaluate the completeness and transparency of RCT reports in this field.The following databases were searched: Medline, EMbase, SCI Expanded, China National Knowledge Infrastructure, the Chinese Biological Medicine Database, VIP database and Wan Fang databases) to search RCT reports on the effect comparison of laparoscopic surgery and open surgery for colorectal cancer in China. Our study evaluated the reporting quality of RCTs based on 22 standards of Consolidated Standards for Reporting Trials (CONSORT) 2010 Statement. Two reviewers responded with 'yes' or 'no' to each standard to judge whether the authors had reported or had recorded concrete details of the reports accomplished in accordance with the requirement of each standard.A total of 40 relevant RCTs were included in the final analysis. For the 'Title and abstract', only three articles (7.5%) could be identified directly from its title as the report of RCTs. For the 'Methods', only three articles (7.5%) applied the method of random allocation of sequences; only two articles (5%) mentioned the type of randomization or gave the description of the mechanism of allocation concealment; no article referred the concrete implementation of random method. Only one article (2.5%) applied the method of blinding or sample size calculation; no article had analysis about the metaphase of an experiment or an explanation of its interruption. For 'results', only one article (2.5%) described participant flow, primary and secondary outcomes with estimated effect size or ancillary analyses. Only 13 articles (32.5%) showed baseline demographic and clinical characteristics, 10 (25%) referred to intention-to-treat analysis, and 12 (30%) mentioned important harms or unintended effects. For the 'discussion', only eight articles (20%) gave the description of trials' limitations and 13 (32.5%) presented the generalizability (external validity, applicability) of the trial findings.The quality of the RCT reports on effect comparison of laparoscopic surgery and open surgery for colorectal cancer in China is poor. The reporting of RCTs in this field should be standardized, according to the specifications of the CONSORT 2010.

Nowadays, peer-to-peer (P2P) file-sharing networks have been widely applied because of the popularity of P2P software. Complete freedom not only allows for the development of P2P networks but also brings about security risks. Malicious nodes can escape the punishment of reputation mechanisms by performing some attacks such as a whitewashing attack. In this paper, we propose a novel reputation mechanism based on two kinds of reputation so as to resist a whitewashing attack. We analyze the reputation and the capacity of the node corresponding to two different behaviors. The relationship between the behavior, capacity, and reputation of the node is discussed. We give the calculation method of our reputation mechanism and run simulations. The results show that our reputation mechanism could defend against a whitewashing attack effectively.

This study is to determine effect of Andrographolide (AD) on the growth of the non-small cell lung cancer cell line H3255. Expression of vascular endothelial growth factor (VEGF), transforming growth factor β1 (TGF-β1), and the activity of protein kinase C (PKC) were also detected. The H3255 cells were treated with 1.0, 2.5, or 5.0 μM AD for 24 h. MTT assay was performed to examine cell viability. Levels of VEGF and TGF-β1 were detected by ELISA. The ATPase activity and PKC activity were tested. AD treatments decreased cell viability via a concentration-dependent manner, leading to decreases in the Na+-K+-ATPase activities (P < 0.05). AD also increased levels of the DNA fragmentation and releasing of lactate dehydrogenase. AD also reduced VEGF and TGF-β1 levels, and inhibited protein kinase C activities in H3255 cells (P < 0.05). AD inhibits proliferation of lung cancer cells via a concentration-dependent manner by a mechanism related to reducing levels of VEGF and TGF-β1. Thus, AD might be a potent anti-lung cancer agent.

It is now fairly common practice to glue steel plates to the tension faces of existing reinforced concrete slabs, as it is an inexpensive and unobtrusive upgrading procedure for strengthening and stiffening. However, the application of this technique to continuous reinforced-concrete beams, as opposed to slabs, is severely restricted by premature debonding of the ends of the tension-face plates through the action of vertical shear forces, that is, shear peeling. An experimental study is presented in which steel plates are glued to the sides of reinforced-concrete beams specifically to inhibit shear peeling of the tension face plates. The results are incorporated into a design procedure for plating the tension faces of continuous composite beams that can allow for any distribution of applied loads, any variation of the cross-section properties along the length of the beam, and the time effects of creep and shrinkage, as well as propped and unpropped construction. The procedure is then applied to the strengthening and stiffening of a continuous reinforced-concrete beam for strength and serviceability requirements.

The unveiling of rules that govern drug-protein interactions is of paramount importance in drug discovery. To discover such relationships, we propose to use a novel method called DPA. Given a set of drug-protein interactions, DPA performs its tasks in several steps: (i) for each drug involved, its substructures are each converted into its fingerprints, (ii) for each protein involved, its protein domains are each converted into its fingerprints, (iii) a dependency measure between each drug substructure and protein domain is then computed based on the known interactions between the drugs and proteins, (iv) the dependency measures are then used to predict previously unknown drug-protein interactions. DPA has the advantage that it is able to perform its tasks effectively without requiring any 3D information about drug and protein structures. It makes use of molecular fingerprints which are information-rich and fast to compute. DPA has been tested with known drug-protein interaction data including enzymes, ion channels, protein-coupled receptors. Experimental results show that it can be very useful for predicting new drug-protein interaction as well as protein-ligand interactions. It can also be used to tackle problems such as ligand specificity thereby facilitating the drug discovery process.

Due to the recent significant improvements in game entertainment, CAD, CAE and some other 3D fields, the number of 3D models is increasing rapidly. As a result, there is an increasing need for procedures supporting the automatic search for 3D objects in databases. In this paper, we present a novel framework to retrieve 3D models in 3 steps. Firstly, users input multiple ordered images of an object as input. Certain photo environment is needed. A voxel model will be generated automatically according to these inputs. Secondly, we provide a tool to modify voxel model. This procedure can help eliminate defects caused by uncertain photo environments. If the model produced by the first step is reasonable, this step will be optional. Finally, the modified model will be retrieved by a method called Solid-D2, which provides a fast and discriminating descriptor for 3D shapes. This algorithm is chosen to err on the side of retrieval speed with certain precision. Related models from the database will be listed. Experimental results indicate that the proposed method is easy-to-use, efficient and applicable for 3D model retrieval.

Active P2P worms spread via hit-list constructed from host-cache of peers and have been one of the greatest threats to P2P network and Internet. P2P worms will improve the capability to attack by using some methods, such as increasing the number of infection threads. Two impact factors, the dynamic characteristic of P2P network and the number of infection threads, are considered in this research. We model the propagation of P2P worms and run the simulations. The results show that the dynamic characteristic of P2P network limits the spread speed of P2P worms. Most peers log in and log out frequently and as a result the target peer will be invalid to be located by P2P worms. In most cases the infection progress will be aborted. The spread speed of P2P worms cannot be accelerated infinitely by increasing the number of infection threads.

Peer-to-Peer(P2P) network has some closer relation-ship with Internet while the scale of P2P network increases. Active P2P worms attack neighbour peers based on hit-list and pose a severe threat to both P2P network and Internet. Due to the complexity of P2P network, the traditional worms propagation model cannot be adequate to exact model P2P worms spread. Both the dynamic characteristic of P2P network and the heterogeneity of peers could have some great impact on active P2P worms spread. A mathematical model of active P2P worms propagation is presented in this paper. We simulate active P2P worms spread after analyzing the mathematical model. The results show that many factors could affect the propagation of active P2P worms such as the state of P2P network, the scan rate of P2P worms, and the security knowledge peers have. We also study the late phase of active P2P worms spread and find that a very small space of P2P network is enough to guarantee active P2P worms self-propagation when peers cannot repair security holes in time for many reasons.

The threats to Internet have been also posed to the social networking sites. In social networks people tend to reduce the original alert and this makes it easier for malware to spread. In this paper we study the threats to social networks in recent years and analyze the targets what the attackers want and the methods how attackers perform the attacks. We separate social networks into two parts: user and social networking site. Then we discuss in details the countermeasures against the threats to social networks. In the end we propose a security framework of social networks.

The activities of the WAM (WAve Model) and the WISE (Waves In Shallow-water Environments) groups have accelerated our understanding of the physics and numerics of waves in shallow water. Two third generation numerical wave models, namely, the WAM which has been extended to coastal areas and the nearshore wave model SWAN (Simulating WAves Nearshore) which replaced the HISWA (Hlndcasting Shallow water WAves) model are implemented in the shallow water of Lake Erie of the Great Lakes with water depths varying from about 5 m to 50 m. The primary purpose of this study is to examine the performance of the WAM and the SWAN running in shallow water mode and using wind forcings provided by a numerical weather prediction model. The two models are run for selected periods and the results are verified against buoy measurements and the operational forecasts from the RCTB (Regional Centre of Thunder Bay) of Canada. This allows an assessment of the performance of the two models and the effect of shallow water on wave forecasting with a view towards operational implementation of either the WAM or the SWAN model, or both, on Lake Erie.

New features have been added and several necessary changes have been made to the standard WAM-cycle4 (WAMC4) model code for it to run efficiently when applied to shallow water regions. The restriction of having a source term integration time step smaller than or equal to the propagation time step was relaxed, considerably reducing the computational time needed. An additional reduction in computing time and an increase in accuracy were obtained by introducing a split-frequency time step. There is now a choice of using the octant or quadrant coordinate system for the propagation of the wave energy. The source term integration and, more particularly, the use of a limiter on the energy growth, were studied. For the evaluation of the energy decay in shallow water areas, different bottom friction formulations and an expression for the energy dissipation due to depth-induced wave breaking were added to the code. The procedure to make nested runs was changed in order to save data storage space and time spent on input/output (I/O) operations. Several other changes were done in order to improve the accuracy in high-resolution applications. A number of simple or idealised example applications are included to illustrate some of these enhancements.