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To provide a theoretical basis for the prevention and treatment of atherosclerosis (AS), the current study aimed to investigate the mechanism underlying the effect of homocysteine (Hcy) on regulating the proliferation, migration and phenotypic transformation of vascular smooth muscle cells (VSMC) via sirtuin-1 (SIRT1)/signal transducer and activator of transcription 3 (STAT3) through Nedd4-like E3 ubiquitin-protein ligase WWP2 (WWP2). Here, Based on the establishment of ApoE-/- mouse models of high Hcy As and the model of Hcy stimulation of VSMC in vitro to observe the interaction between WWP2 and STAT3 and its effect on the proliferation, migration, and phenotypic transformation of Hcy-induced VSMC, which has not been previously reported. This study revealed that WWP2 could promote the proliferation, migration, and phenotype switch of Hcy-induced VSMC by up-regulating the phosphorylation of SIRT1/STAT3 signaling. Furthermore, Hcy might up-regulate WWP2 expression by inhibiting histone H3K27me3 expression through up-regulated UTX. These data suggest that WWP2 is a novel and important regulator of Hcy-induced VSMC proliferation, migration, and phenotypic transformation. [ABSTRACT FROM AUTHOR]

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The right internal jugular vein (IJV) is an important access site for hemodialysis catheterization. Venous cannulation failure is usually caused by central venous stenosis and is rarely related to vessel malformation. We herein present a case of failure to place a tunneled hemodialysis catheter into the right IJV. The patient had an arteriovenous fistula in the right arm with inadequate flow and a history of multiple central venous catheterizations. The guidewire was repeatedly misplaced into the right subclavian vein (SV) regardless of the technique used. Computed tomography venography revealed that the inferior segment of the right IJV drained into the ipsilateral SV. To the best of our knowledge, this is the first report of catheterization failure due to abnormal drainage of the right IJV into the ipsilateral SV.

Chemically synthetic nanomotors can consume fuel in the environment and utilize the self-generated concentration gradient to self-propel themselves in the system. We study the collective dynamics of an ensemble of sphere dimers built from linked catalytic and noncatalytic monomers. Because of the confinement from the fuel field and the interactions among motors, the ensemble of dimer motors can self-organize into various nanostructures, such as a radial pattern in the spherical fuel field and a staggered radial pattern in a cylindrical fuel field. The influence of the dimer volume fraction on the self-assembly is also investigated and the formed nanostructures are analyzed in detail. The results presented here may give insight into the application of the self-assembly of active materials. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the clinical application of moist wound dressings in wound care for patients with the tracheostomy. Background: Tracheostomy patients may suffer from many complications. Moist dressings have been proposed to lower complication rates for patients with the tracheostomy. Design: A Preferred Reporting Items for Systematic Reviews and Meta‐analyses (PRISMA) checklist‐guided meta‐analysis of randomised and controlled clinical trials. Method: In this meta‐analysis, two reviewers independently searched PubMed, EMBASE, Cochrane Library, Web of Science, CNKI and Wanfang databases for controlled clinical trials (CCTs) comparing the use of moist dressings and gauze for tracheostomy patients. The reviewers screened studies according to the inclusion criteria and extracted data from published reports independently. The outcome of site infection and pressure ulcer incidence, the frequency of dressing changes and wound closing time were evaluated by random‐effects or fixed‐effects meta‐analysis. Results: After the screening, ten studies including 1,220 participants were eligible for analysis. The result showed that the incidence of site infection and pressure ulcer was significantly reduced in the moist dressings group compared with the gauze group. Moist dressings were also associated with significant reductions in the frequency of dressing changes and wound closing time. These results were assessed as moderate‐ to low‐quality evidence. Conclusion: Moist dressings seem to be beneficial to tracheostomy patients, giving a lower incidence of site infection and pressure ulcers as well as shorter wound closing times and lower dressing change frequency. More high‐quality trials are needed to support this finding. Relevance to clinical practice: The findings offer clinicians an assessment of and evidence for the efficacy of moist dressings, which may be a superior option for patients with a tracheotomy. [ABSTRACT FROM AUTHOR]

Abstract: The surface of an orthopaedic implant plays a crucial role in determining the adsorption of proteins and cell functions. A detailed comparative study has been made of the in vitro osteoblast responses to coarse‐grained (grain size: 500 μm), ultrafine‐grained (grain size: 100 nm), coarse‐porous (pore size: 350 nm), and fine‐porous (pore size: 155 nm) surfaces of Ti‐20Mo alloy. The purpose was to provide essential experimental data for future design of orthopaedic titanium implants for rapid osseointegration. Systematic original experimental data was produced for each type of surfaces in terms of surface wettability, cell morphology, adhesion, growth, and differentiation. Microscopic evidence was collected to reveal the detailed interplay between each characteristic surface with proteins or cells. Various new observations were discussed and compared with literature data. It was concluded that the coarse‐porous surfaces offered the optimum topographical environment for osteoblasts and that the combination of ultrafine grains and considerable grain boundary areas is not an effective way to enhance cell growth and osteogenic capacity. Moreover, pore features (size and depth) have a greater effect than smooth surfaces on cell growth and osteogenic capacity. It proves that cells can discern the difference in pore size in the range of 100–350 nm. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2020–2033, 2018. [ABSTRACT FROM AUTHOR]

Gold (Au) nanocap arrays and hollow gold nanocap particles were prepared by dip-coating technique combined with wet chemical reduction method, and followed by sonication and dissolution of the silica colloidal template. The surface morphologies and optical properties of the obtained samples were characterized by scanning electron microscopy, transmission electron microscope, and ultraviolet-visible spectrophotometer, respectively. Gold nanocap arrays and hollow gold nanocap particles were used as substrates to detect the surface-enhanced Raman scattering spectra of malachite green and methylene blue (MB), respectively. It was found that the gold nanocap arrays had higher enhancement ability than hollow gold nanocap particles, with enhancement factor of 1.3 × 105and 3.5 × 103, respectively. In addition, gold nanocap arrays exhibited excellent reproducibility with a relative standard deviation of less than 5% and about 10% across a single substrate and between different substrates, respectively. The minimum detection limit for MB adsorbed on hollow gold nanocap particles was down to 0.01 µM. [ABSTRACT FROM AUTHOR]

Phenolic resin (PF) and molybdic acid–modified phenolic (Mo-PF) have been synthesized and developed and combined with polyfluo wax (PFW) to fabricate PF-PFW and Mo-PF-PFW composite coatings. The effects of applied load and sliding speed on the tribological properties of the phenolic composite coating were evaluated using a block-on-ring wear tester. Compared to the PF composite coating, the Mo-PF displayed a lower friction coefficient and a higher wear life under all tested conditions. Scanning electron microscope (SEM) investigation showed that the Mo-PF composite coating had a smooth worn surface after the friction test, and a continuous and uniform transfer film was formed on the surface of the counterpart ring. The improved tribological properties of Mo-PF composite coating resulted from its enhanced thermal properties. [ABSTRACT FROM PUBLISHER]

The sub-binary systems Al-Ti, Ti-V, and Al-V are reviewed and adopted from the previous assessments, the thermodynamic analysis of the Al-Ti-V ternary system is performed by the CALPHAD approach, and a set of self-consistent thermodynamic parameters of the ternary system are obtained. Furthermore, the isothermal sections of this system at 1073 K, 1173 K, 1273 K, 1373 K, and 1473 K (800 °C, 900 °C, 1000 °C, 1100 °C, and 1200 °C) and the ternary invariant equilibria are calculated and compared with the corresponding experimental data, and all are in good agreement with most of the experimental results. Thus, the optimized thermodynamic parameters in this study may provide more accurate guidance to develop the new alloys involving it. [ABSTRACT FROM AUTHOR]

The α + β-type Ti-4.5Al-6.9Cr-2.3Mn alloy has been theoretically designed on the basis of assessment of the Ti-Al-Cr-Mn thermodynamic system and the relationship between the molybdenum equivalent and mechanical properties of titanium alloys. The alloy is successfully prepared by the split water-cooled copper crucible, and its microstructures and mechanical properties at room temperature are investigated using the OM, SEM, and the universal testing machine. The results show that the Ti-4.5Al-6.9Cr-2.3Mn alloy is an α + β-type alloy which is consistent with the expectation, and its fracture strength, yield strength, and elongation reach 1191.3, 928.4 MPa, and 10.7 pct, respectively. Although there is no strong segregation of alloying elements under the condition of as-cast, the segregation of Cr and Mn is obvious at the grain boundary after thermomechanical treatment. [ABSTRACT FROM AUTHOR]

High-quality epi-MgO buffer layers under different O2/Ar pressure ratios are fabricated by rf magnetron sputtering on textured IBAD-MgO templates. Under the total deposition pressure remaining constant (14 Pa), the effect of changing the ratio of O2/Ar pressure from 1:4 to 3:2 on the microstructure and surface morphology of epi-MgO films is studied. The microstructure and morphology of epi-MgO are fully characterized by x-ray diffraction, atom force microscope and scanning electron microscope. The best texture quality of epi-MgO with an out-plane Δω value of 1.8° and an in-plane ΔΦ value of 5.22° are obtained under the ratio of O2/Ar pressure 3:2. Further, the surface morphology indicates that the surface of epi-MgO is smooth with rms surface roughness about 4.7 nm at O2/Ar pressure ratio 3:2. After that, GdBa2Cu3O7–δ (GBCO) layers are deposited on the CeO2 cap layer buffered epi-MgO/IBAD-MgO templates to assess the efficiency of such a buffer layer stack. The critical current density of GBCO films (thickness of 200 nm) is higher than 3 MA/cm2, indicating that epi-MgO/IBAD-MgO is promising for depositing superconducting layers with a higher critical current density. [ABSTRACT FROM AUTHOR]

Colloidal silver nanoparticles were prepared by a simple chemical reduction method. The effect of L-cysteine on the surface-enhanced Raman scattering activity of colloidal silver nanoparticles was investigated by using malachite green as a probe molecule. It was found that the surface-enhanced Raman scattering activity of colloidal silver nanoparticles was improved tremendously with the help of L-cysteine. The possible reasons for this enhancement effect were given. Specifically, in silver colloidal solution, no surface-enhanced Raman scattering spectrum of malachite green was observed at a relatively low concentration (≤2.5 × 10−5 mol/L). However, well-resolved and high-quality surface-enhanced Raman scattering spectra of malachite green were successfully obtained after the addition of L-cysteine to silver colloids, and the minimum detection limit for malachite green was down to 10−8 mol/L. [ABSTRACT FROM AUTHOR]

In order to overcome the weakness of large ZigBee node, complex network and high cost in the harsh environment, a design of wireless sensor network node based on super low power consumption MCU MSP430 and RF chip CC2430 is proposed, and RF front-end CC2591 is used to improve the trans-mission power and receive sensitivity, thus extending the transmission distance. The test results show that the stability of the system is improved and network coverage is increased because of the MCU and the RF front-end [ABSTRACT FROM AUTHOR]

Copper nanocap arrays, consisting of a SiO2 core with a Cu cap, were prepared by chemical synthesis combined with physical evaporation technique. The obtained samples were characterized by scanning electron microscopy, atomic force microscopy, X-ray diffraction, and ultraviolet-visible-near-infrared spectrophotometer. The copper nanocap arrays were found to exhibit tunable surface plasmon resonance (SPR) absorption peaks that were red-shifted as the ratio of the SiO2 core diameter to the Cu cap thickness increased. While the cap thickness varied between 20 nm and 50 nm, the SPR peak shifted from 1650 nm to 1230 nm. While the core diameter varied between 140 nm and 400 nm, the longitudinal SPR peak shifted from 1243 nm to 1830 nm. [ABSTRACT FROM AUTHOR]

The motion of spiral waves in excitable media driven by a weak pacing around the spiral tip is investigated numerically as well as theoretically. We presented a Bifurcations diagram containing four types of the spiral motion induced by different frequencies of pacing: rigidly rotating, inward-petal meandering, resonant drift, and outward-petal meandering spiral. Simulation shows that the spiral resonantly drifts when the frequency of pacing is close to that of the spiral rotation. We also find that the speed and direction of the drift can be efficiently controlled by means of the strength and phase of the local pacing, which is consistent with analytical results based on the framework of the weak deformation approximation. [ABSTRACT FROM AUTHOR]