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Based on a modification of a magnetohydrodynamic turbulence model, a numerical study was performed to investigate the effects of transverse uniform and gradient magnetic field on the turbulent flow and heat transfer characteristics of a low melting point molten salt in a stainless steel pipe. With the Hartmann number from 0 to 80, the numerical results showed that the fluid flow displayed anisotropic distributions under the magnetic field with decrease of velocity in the mainstream region, and decrease of turbulent intensity, whereas the flow velocity increased in the boundary layer near the Hartmann and Roberts wall. Especially, a velocity jet phenomenon was observed in the Roberts boundary layers at higher Hartmann number in the uniform magnetic field or the positive gradient magnetic field. Under the gradient magnetic field, the flow and heat transfer of molten salt displayed much more variations than under the uniform magnetic field. The magnetohydrodynamic calculation results proposed here might be helpful to the design of the composite heat transfer system for molten salt in actual industrial applications. • Both the uniform and non-uniform magnetic field were applied in pipe flow of molten salt for comparison. • A modified MHD turbulence model was established for turbulent flow of molten salt. • The characteristics of flow and heat transfer were numerically studied for a low melting point molten salt. • The complex influence of magnetic field to flow and heat transfer of molten salt was observed. [ABSTRACT FROM AUTHOR]

In order to investigate the heat transfer characteristics of mixed molten salt, an experimental setup for the submerged jet impingement has been established in this paper. Firstly, an experimental investigation on heat transfer of submerged jet impingement with water as working fluid was carried out to verify reliability of experimental method. A good consistence was found between experimental results and those classical correlations from references for stagnation heat transfer, which indicate the reliability and accuracy of experimental method. On the basic of ensuring the reliability of experiment, a series of studies on jet impingement experiments were carried out with new mixed molten salt. The results indicated that effect of submerged jet impingement heat transfer enhanced gradually with the increase Reynolds number and the heat transfer characteristics at the stagnation are analogous with the water in the scope of experimental investigations. Further, a correlation about quaternary mixed molten salt was proposed based on experimental data. At same Reynolds number, the Nusselt number of mixed molten salt is obviously higher than that of water at stagnation zone because of its higher Prandtl number and becomes lower than water at larger radial distance due to its higher viscosity. The results indicated that thermophysical properties of working fluid have an enormous influence on the Heat transfer performance. The experimental results in this paper provide a necessary technical guarantee for the study of heat transfer of the high temperature fluid. [ABSTRACT FROM AUTHOR]

In this paper, a prediction model for the crystallization fouling was proposed on the basis of the Kern-Seaton model for the heat transfer and fouling process in circulated cooling water. The fouling deposition and removal process were analyzed, respectively, for the fouling process, on which the coupling effects of the scale layer, temperature and ions concentration were considered. The model calculation may predict the fouling resistance variations in fouling process, which were in good agreement with experimental data from references within a range of given conditions especially for the turbulent flow, indicating the model applicability for actual process. Since the model can be used without requirement of a large amount of measured data for fitting, it gives a more convenient way for predicting fouling process of heat exchangers in industry. • A prediction model for CaCO 3 crystallization fouling in circulating cooling water was established. • The fouling deposition and removal processes were all analyzed in the model respectively. • The coupling effects of fouling layer, temperature and concentration of fouling ions were considered. • The calculation of model may provide a fouling prediction without requirement of a number of experimental data for fitting. [ABSTRACT FROM AUTHOR]

The content authenticity is critical for secure transmission of multimedia information. As a promising solution, perceptual image hashing has gain great attention. In this paper, we develop a novel algorithm for generating an image hash based on invariants of radial Tchebichef moments. The idea is justified by the fact that the radial Tchebichef moments represent the image under the orthogonal kernel, which has the desirable qualities of orthogonality and robustness. The hash values are achieved by adaptive quantization of the invariants of radial Tchebichef moments, then the random Gay code is applied in the discrete–binary conversion stage to enhance the expected discriminability. Experiments are conducted to show that the proposed hashing algorithm has superior robustness and discrimination performance compared with other state-of-the-art algorithms, in terms of receiving operating characteristic (ROC) curves. [ABSTRACT FROM AUTHOR]

Abstract: Ethene hydrogenation reaction, catalyzed by an iridium atom adsorbed on γ-Al2O3(001) surface, is studied via ab initio calculations based on density functional theory (DFT). The catalyzed reaction process and activation energy are compared with the counterparts of a reaction occurs in vacuum condition. It is found that the activation energy barrier is substantially lowered by the adsorbed Ir atom on the γ-Al2O3(001). The catalyzed reaction is modeled in two steps: (1) Hydrogen molecular dissolution and then bonded with C2H4 molecular. (2) Desorption of the C2H6 molecular from the surface. [Copyright &y& Elsevier]

Abstract: Iridium adsorption on γ-Al2O3 (001) surface has been studied using the ab initio calculation method and the electronic structures of the bare and the Ir adsorbed γ-Al2O3 (001) surfaces have been analyzed. By modeling different adsorption sites, one can conclude that the energetically most favorable sites for the Ir are the top sites of the O atoms at the γ-Al2O3 (001) surface terminated with octahedral Al. Charge redistribution around the Ir atom adsorbed on the surface improves the activity of the Ir atom as a catalyst. [Copyright &y& Elsevier]

• An experimental setup for free-surface jet impingement heat transfer of molten salt. • A new correlation of stagnation heat transfer with molten salt proposed. • Heat transfer characteristics of molten salt along heat transfer surface obtained. An experimental study of free-surface jet impingement was carried out with compound molten salt to understand its characteristics of heat transfer. Based on pre-experimental verification on the reliability of experimental method by water as working fluid, a compound molten salt was chosen as a new working fluid to conduct experiment of free-surface jet impingement. The heat transfer of molten salt at stagnation point was investigated in detail, and the Nusselt number of molten salt increased with increasing of the Reynolds number and the Prandtl number, and was nearly constant with increasing of nozzle-to-plate spacing at present ranges. The data was correlated by an empirical formula, which was compared with those classical correlations from references. Next, the variation of the Nusselt number of molten salt was also verified along heated surface. It was shown that the local Nusselt number decreased monotonously with increasing of lateral distances from stagnation point, and increased with increasing of the Reynolds number. The profiles of the Nusselt number were nearly unchanged for different nozzle-to-plate spacing, which can be well correlated by a normalized formula. This work focused on the heat transfer characteristics of the molten salt in free-surface jet impingement, which may be recognized as a reference for promoting the application of molten salt in heat transfer process, especially in high temperature situations. [ABSTRACT FROM AUTHOR]

Highlights • Autism is a behaviorally defined neurodevelopmental disease. • Macaques provide unique advantages over rodents to model human autism. • This review focuses on behavioral phenotyping assays for macaque models of autism. Abstract Autism is a behaviorally defined neurodevelopmental disease characterized by social communication and social interaction deficits, as well as repetitive behaviors and restricted interests. Although the causes of autism are extremely complex, involving genes, environments and gene-environment interactions, genetic mutations are the important risk factors. For this reason, preclinical research is now shifting into focusing on generating transgenic and knockout models, especially using macaques, which are the closest relatives to humans. In spite of unique advantages of macaques over rodents in both functionally specialized brain structures and highly sophisticated social behaviors, the limited availability of phenotype screening tools restricts their translational utility. Here, this review focuses specially on behavioral phenotyping assays for macaque models of autism. In the first part, the existing behavioral tests are discussed, and the second part is devoted to some few, in our view, very promising tests of new developments. In years to come, we should develop macaque models with high construct validity, improve face validity by designing more specialized behavioral screening tools, strengthen collaborative efforts between rodent and macaque models, and ultimately translate the results from animal models into human clinical trials. [ABSTRACT FROM AUTHOR]

The performance of real-time (RT) precise positioning can be improved by utilizing observations from multiple Global Navigation Satellite Systems (GNSS) instead of one particular system. Since the end of 2012, BeiDou, independently established by China, began to provide operational services for users in the Asia-Pacific regions. In this study, a regional RT precise positioning system is developed to evaluate the performance of GPS/BeiDou observations in Australia in providing high precision positioning services for users. Fixing three hourly updated satellite orbits, RT correction messages are generated and broadcasted by processing RT observation/navigation data streams from the national network of GNSS Continuously Operating Reference Stations in Australia (AUSCORS) at the server side. At the user side, RT PPP is realized by processing RT data streams and the RT correction messages received. RT clock offsets, for which the accuracy reached 0.07 and 0.28 ns for GPS and BeiDou, respectively, can be determined. Based on these corrections, an accuracy of 12.2, 30.0 and 45.6 cm in the North, East and Up directions was achieved for the BeiDou-only solution after 30 min while the GPS-only solution reached 5.1, 15.3 and 15.5 cm for the same components at the same time. A further improvement of 43.7, 36.9 and 45.0 percent in the three directions, respectively, was achieved for the combined GPS/BeiDou solution. After the initialization process, the North, East and Up positioning accuracies were 5.2, 8.1 and 17.8 cm, respectively, for the BeiDou-only solution, while 1.5, 3.0, and 4.7 cm for the GPS-only solution. However, we only noticed a 20.9% improvement in the East direction was obtained for the GPS/BeiDou solution, while no improvements in the other directions were detected. It is expected that such improvements may become bigger with the increasing accuracy of the BeiDou-only solution. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: A novel H1N1 vaccine was manufactured in response to the pandemic in 2009. This study describes the willingness to be vaccinated for H1N1 among healthcare workers (HCWs) in primary healthcare clinics with and without chronic medical conditions, their reasons for refusing vaccination and whether they sought additional information to make an informed decision for the vaccination. Materials and methods: An anonymous survey was conducted in November 2009 among all medical, nursing, allied health and operations HCWs in nine primary care clinics in Singapore. Participants were asked if they had any chronic medical conditions associated with influenza-related complications (example: asthma, stroke, heart disease, cancer, diabetes mellitus, renal disease), their perception towards vaccination for H1N1 and against seasonal influenza within the preceding 2 years. Results: The initial response rate was 80%, of which 711 (54.7%) of the completed surveys were analysed. Among the 711 respondents, 16.6% reported having at least 1 chronic disease. Asthma (10.8%), hypertension (10.4%) and dyslipidaemia (9.8%) were the main chronic conditions. Only 39.4% of respondents were willing to be vaccinated against H1N1. Males were 2.07 (95% CI 1.19–3.62) times more likely than females to receive the H1N1 vaccination; the 45–54 and 55+ years old were 2.12 (95% CI 1.06–4.24) and 2.44 (95% CI 1.13–5.27) times more willing than those below 25 years old; and those who considered accepting the seasonal influenza vaccine were 7.0 times more likely than those who did not (95%CI 4.48–10.92). The 2 principal barriers were “fear of side effects” and “unsure of vaccine''s effectiveness”. Although 78% attended some H1N1-related talks, only 7% of all HCWs felt that they had sufficient information. Most wanted more information about the vaccine''s safety profile and contraindications. Conclusion: Fewer than 40% of HCWs expressed willingness to receive the H1N1 vaccination, lower than past rates of influenza vaccine. HCWs in primary care clinics who had a chronic condition did not perceive themselves to be at higher risk of developing H1N1-related complications and were not more willing than the rest of the HCWs to accept H1N1 vaccination. Vaccine''s side effects and effectiveness were the main concerns. Uptake of H1N1 vaccine may improve with targeted health information covering the vaccine''s safety profile. [Copyright &y& Elsevier]

Shale samples collected from seven wells in the southeastern Ordos Basin were tested to investigate quantitatively the pore structure and fractal characteristics of the Lower Permian Shanxi Shale, which was deposited in a marine-continental transitional (hereinafter referred to as the transitional) environment. Low-pressure nitrogen adsorption data show that the Shanxi Shale exhibits considerably much lower surface area (SA) and pore volume (PV) in the range of 0.6–1.3 m 2 /g and 0.25–0.9 ml/100 g, respectively. Type III kerogen abundant in the transitional Shanxi Shale were observed to be poorly developed in the organic pores in spite of being highly mature, which resulted in a small contribution of organic matter (OM) to the SA and PV. Instead, I/S (illite-smectite mixed clay) together with illite jointly contributed mostly to the SA and PV as a result of the large amount of inter-layer pores associated with them, which were evident in broad-ion-beam (BIB) imaging and statistical analysis. Additionally, the Shanxi Shale has fractal geometries of both pore surface and pore structure, with the pore surface fractal dimension (D1) ranging from 2.16 to 2.42 and the pore structure fractal dimension (D2) ranging from 2.49 to 2.68, respectively. The D1 values denote a pore surface irregularity increase with an increase in I/S and illite content attributed to their more irregular pore surface compared with other mineralogical compositions and OM. The fractal dimension D2 characterizing the pore structure complexity is closely related to the pore arrangement and connectivity, and I/S and illite decrease the D2 when their contents increase due to the incremental ordering degree and connectivity of I/S- or illite-hosted pores. Meanwhile, other shale constituents (including kaolinite, chlorite, and OM) that possess few pores can significantly increase the pore structure complexity by way of pore-blocking. [ABSTRACT FROM AUTHOR]

Purpose To investigate oncogenic platelet-derived growth factor receptor(PDGFR) fusion genes involvement in hematological malignancies, the advances in the PDGFR fusion genes diagnosis and development of PDGFR fusions inhibitors. Methods Literature search was done using terms “PDGFR and Fusion” or “PDGFR and Myeloid neoplasm” or ‘PDGFR and Lymphoid neoplasm’ or “PDGFR Fusion Diagnosis” or “PDGFR Fusion Targets” in databases including PubMed, ASCO.org, and Medscape. Results Out of the 36 fusions detected, ETV6(TEL)-PDGFRB and FIP1L1-PDGFRA fusions were frequently detected, 33 are as a result of chromosomal translocation, FIP1L1-PDGFRA and EBF1-PDGFRB are the result of chromosomal deletion and CDK5RAP2- PDGFRΑ is the result of chromosomal insertion. Seven of the 34 rare fusions have detectable reciprocals. Conclusion RNA aptamers are promising therapeutic target of PDGFRs and diagnostic tools of PDGFRs fusion genes. Also, PDGFRs have variable prospective therapeutic strategies including small molecules, RNA aptamers, and interference therapeutics as well as development of adaptor protein Lnk mimetic drugs. [ABSTRACT FROM AUTHOR]

Non-small cell lung cancer (NSCLC) remains one of the most metastasizing tumors, and directional cell migration is critical for targeting tumor metastasis. GIT2 has been known to bind to Paxillin to control cell polarization and directional migration. However, the molecular mechanisms underlying roles of GIT2 in controlling cell polarization and directional migration remain elusive. Here we demonstrated GIT2 control cell polarization and direction dependent on the regulation of Golgi through RUSC2. RUSC2 interacts with SHD of GIT2 in various lung cancer cells, and stabilizes GIT2 (Mazaki et al., 2006; Yu et al., 2009) by decreasing degradation and increasing its phosphorylation. Silencing of RUSC2 showed reduced stability of GIT2, defective Golgi reorientation toward the wound edge and decreased directional migration. Moreover, short-term EGF stimulation can increase the interaction between RUSC2 and GIT2, prolonged stimulation leads to a decrease of their interaction through activating Rab35. Silencing of Rab35 also reduced stability and phosphorylation of GIT2 and decreased cell migration. Taken together, our study indicated that RUSC2 participates in EGFR signaling and regulates lung cancer progression, and may be a new therapeutic target against lung cancer metastasis. [ABSTRACT FROM AUTHOR]

• The inappropriate method of separating pseudorange bias into a purely receiver-dependent part or purely satellite-dependent part in mixed network is proved. • A simplified algorithm of the clock offset estimation with pseudorange bias correction is derived. • The pseudorange bias is used to improve the accuracy and performance of precise point position. The pseudorange bias inconsistencies are notably originating primarily from the individual chip shape distortions in the ranging signals, these distortions cause different shifts of the correlator's tracking point for receivers, as a result giving rise to a different pseudorange bias for each pseudorange observation. The different bias should be properly dealt with in the process of satellite clock offset estimation when receivers of mixed types are used. In this work, using observations from 140 international global navigation satellite system (GNSS) service stations, the pseudorange bias was calculated, and the effect of inconsistent biases on satellite clock offset estimation from different receiver networks was investigated. The inconsistencies between the GPS satellites were ranging from −6 ns to 4 ns. For GALILEO and BDS, the biases are significant, ranging from −20 ns to 40 ns and −60 ns to 40 ns, respectively. The biases of the individual satellites are receiver-related and statistically stable from day to day. The influence of pseudorange bias was strikingly noticeable, and can improve the accuracy of the estimated clock offset by several ps for GPS; and by more than 15 ps for GALILEO and BDS after considering bias inconsistencies. Furthermore, owing to the pseudorange bias correction, the convergence and positioning performance have improved significantly, with an improvement of more than 12 % for the static precise point position (PPP), and more than 10 % for the kinematic PPP. [ABSTRACT FROM AUTHOR]

Highlights: [•] Both the morphology and composition of PdAg surfaces are considered in this study. [•] The d-electron activities of Pd atoms are compared among these three surfaces. [•] The close-packed surface alloy is not better than less-densely packed surfaces. [•] The (100) surface activity remains well when the surface Ag concentration grows. [Copyright &y& Elsevier]

Abstract: The small GTPases regulate many major biological processes in both tumorigenesis and tumor progression such as cell survival, actin cytoskeleton organization, cell polarity and movement. Wnt5a, a non-canonical Wnt family member, is implicated in the activation of small GTPases in breast cancer. We previously demonstrated that Wnt5a signaling stimulates the migration of breast cancer cells MDA-MB-231 via activating RhoA. However, we found here that RhoA activation was not enhanced by Wnt5a in breast cancer cells MCF-7. The conflicting results prompted us to further probe novel small GTPases in response to Wnt5a and investigate the mechanisms whereby cell migration is regulated. We showed here that Wnt5a dose dependently activated Dvl2, Rab35 and Rac1 and subsequently promoted the migration of MCF-7 cells, which was, however, abolished by knocking down Wnt5a expression via small interfering RNA (siRNA) transfection. Dvl2 siRNA significantly decreased background and Wnt5a-induced Rab35/Rac1 activation and, consequently, cell migration. Rab35 short hairpin RNA (shRNA) remarkably inhibited background and Wnt5a-induced Rac1 activation and cell migration. Additionally, blockade of Rac1 activation with Rac1 siRNA suppressed background and Wnt5a-induced cell migration. Co-immunoprecipitation and immunofluorescence assays showed that Dvl2 bound to Rab35 in mammalian cells. Taken together, we demonstrated that Wnt5a promotes breast cancer cell migration via the Dvl2/Rab35/Rac1 signaling pathway. These findings implicate Wnt5a signaling in regulating small GTPases, which could be targeted for manipulating breast cancer cell migration. [Copyright &y& Elsevier]

Abstract: Wnt5a, a non-transforming Wnt family member, plays complicated roles in oncogenesis and cancer metastasis. However, Wnt5a signaling in gastric cancer progression remains poorly defined. In this study, we found that Wnt5a dose-dependently stimulated the migration of human gastric cancer cells (SGC-7901), with the maximal effect at 100ng/mL, via enhancing phosphorylation of PI3K/Akt and GSK3β and activating RhoA. Pharmaceutical inhibition of PI3K with LY294002 or Akt siRNA significantly decreased Wnt5a-induced GSK3β phosphorylation and consequently cell migration. Additionally, GSK3β siRNA remarkably inhibited Wnt5a-induced RhoA activation, stress fiber formation and cell migration. Analogously, pre-treatment with LiCl, which induced phosphorylation of GSK3β at Ser9, increased Wnt5a-induced cell migration. Finally, ectopic expression of dominant negative RhoA (N19) suppressed Wnt5a-induced cell migration. Taken together, we demonstrated for the first time that Wnt5a promoted gastric cancer cell migration via the PI3K/Akt/GSK3β/RhoA signaling pathway. These findings could provide a rationale for designing new therapy targeting gastric cancer metastasis. [Copyright &y& Elsevier]