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This paper experimental investigated the shock wave propagation characteristics and selfrignition produced by the high-pressure hydrogen release in tile three-way tubes. Two Y-shaped tubes (60°, 120°) and one T shaped tube(180°) wereused in the experiments and the initial release pressure was 3-8 MPa. The pressure and photoelectric signals in tubes were recorded by the sensor. The results showed that the intensity of shock wave was enhanced or attenuated during the entire releasing process, but the dominant effect was distinct under different conditions and the two effects synergistically affected the occurrence possibility of self-ignition. The critical release pressure for selfrignition in the three-way tubes decreased with the increasing of the bifurcation angle, and the most difficult to occur the self-ignition was the 60° Y-tube in this study. In addition, quenching occurred in the 60° Y-tube when the initial release pressure was 6 MPa, because the temperature of the mixture dropped by the expansion effect. Furthermore, the intensity of the reflected shock wave was not strong enough to promote hydrogen rekindled. This experimental results have reference value for the safety of high-pressure hydrogen production, storage and transportation, and are helpful to understand the influence of bifurcation structure on self-ignition in energy application. [ABSTRACT FROM AUTHOR]

Constitutive photomorphogenic 1 (COP1) belongs to the COP-de-etiolated (DET)-fusca (FUS) protein family and has been demonstrated to suppress prostate adenocarcinomas and other types of tumor, such as liver and gastric cancer. The present study investigated the expression of COP1 and its downstream factor, ets variant 1 (ETV1) in renal cell carcinoma (RCC) tissue samples, and evaluated the correlation of COP1 expression levels with the clinicopathological characteristics of RCC. In addition, the role of COP1 in the proliferation and migration of RCC ACHN cells was investigated. The results demonstrated significantly downregulated COP1 expression levels in the RCC intratumors, which was negatively associated with clinicopathological characteristics, such as tumor size, tumor-node-metastasis (TNM) stage and lymph node or distant metastasis. COP1 was demonstrated to markedly reduce the colony size of RCC ACHN cells, and inhibit the migration and invasion of ACHN cells. In addition, ETV1 and matrix metalloproteinase 7 (MMP7) mRNA and protein expression levels were significantly downregulated by the overexpressed COP1. Thus, the results of the present study demonstrate the reduced expression of COP1 and the upregulated expression of ETV1 in RCC tissue samples, which was associated with a high tumor-node-metastasis stage of RCC. Furthermore, the overexpression of COP1 in the RCC ACHN cells inhibited the migration and invasion of ACHN cells, and downregulated ETV1 and MMP7 expression levels. The present study demonstrated the tumor suppressive role of COP1 in RCC by inhibiting cell migration. [ABSTRACT FROM AUTHOR]

Yb 2 Ti 2 O 7 exhibits ferromagnetic and magnetic properties, which are expected to exert a discernible influence on the thermoelectric properties of SrTiO 3 composite. The La-Yb-Nb-doped SrTiO 3 powders, synthesized via the hydrothermal method, were prepressed and then buried in carbon powder before being sintered in a muffle furnace at 1573 K for 5 h. The Yb dopant precipitated during the sintering process, leading to the in-situ formation of Yb 2 Ti 2 O 7. The content of Yb 2 Ti 2 O 7 increased with an increasing Yb concentration, resulting in a reduction in thermal conductivity and grain boundary potentials, and an increase in the peak electrical conductivity. The La and Nb dopants affect the electrical conductivity and the Seebeck coefficient. Therefore, by controlling the La, Nb, and Yb ratios, the La8Yb2Nb15 sample achieved the largest power factor (PF) value of 0.9 mWm−1K−2 and a low thermal conductivity of 2.9 W m−1K−1, resulting in a high ZT value of 0.32 at 1000 K. [ABSTRACT FROM AUTHOR]

Both thermoelectric conversion materials and infrared (IR) radiation materials enjoy broad applicability in energy utilization and aerospace. Therefore, it is essential to study the relationship between the physical properties of these two materials. This paper investigates the connection between the thermoelectric properties and the IR radiation properties using a SrTiO3-based thermoelectric material. As a result, we have demonstrated the correlation between a material's Seebeck coefficient and IR emissivity using experimental data and theoretical calculations. With increasing Seebeck coefficient, the IR emissivity increases. The material's IR emissivity falls as its electrical conductivity rises, and vice versa. When the material's thermal gradient is low, its IR emissivity influences its IR radiation energy. As the thermal gradient of the material increases, the IR radiation energy incident on the material surface is mainly influenced by the material's thermal conductivity. This work provides a fresh perspective on modulating the IR radiation and thermoelectric properties using the connection found in this study. The results provide theoretical guidance for studies at the intersection of thermoelectric and IR materials. [ABSTRACT FROM AUTHOR]

Background/Aims: Vascular calcification, which involves an active cellular transformation of vascular smooth muscle cells into bone forming cells, is prevalent and predicts mortality in dialysis patients. Its mechanisms are complex and unclear. We presume that irisin, a newly identified myokine also may play roles in vascular calcification in hemodialysis patients. This study aims to evaluate serum irisin levels and establish their relation to vascular calcification and other parameters in hemodialysis patients. Methods: A total of 150 patients on maintenance hemodialysis treatment and 38 age- and sex-matched healthy controls were enrolled in this cross-sectional study. Serum irisin concentrations were measured by ELISA. Vascular calcification was evaluated by abdominal aortic calcification scores. Results:Serum irisin concentrations were significantly lower in hemodialysis patients than in controls [52.8 (22.0, 100.0) vs. 460.8 (434.8, 483.4) ng/ml, P<0.01]. In addition, irisin was negatively correlated with the parathyroid hormone level (P=0.01). The HD patients with vascular calcification showed significantly lower serum irisin concentrations [39.0 (21.7, 86.2) vs.79.0 (39.5, 130.2) ng/mL, P<0.01]. Compared with the group without vascular calcification multivariate logistic regression analyses revealed that serum irisin, HD vintage and age were significant independent determinant factors for vascular calcification in HD patients. Conclusion: Our results are the first to provide a clinical evidence of the association between serum irisin and vascular calcification in HD patients. Lower irisin levels, long-term hemodialysis and old ages are independent risk factors in HD patients. [ABSTRACT FROM AUTHOR]

The exploration of highly efficient and low-cost bifunctional electrocatalyst is essential for overall water splitting, especially for industrial application under alkaline conditions. Herein, we propose a controllable structural engineering strategy of constructing heterogeneous layered electrocatalyst with wetting surface for hydrogen evolution reaction and oxygen evolution reaction. Heterogeneous layered NiFe LDH (layered double hydroxide)/CoFeP/NF (Ni foam) with superhydrophilic surfaces is successfully fabricated by successive electrodeposition, phosphorization and solvothermal method. The NiFe LDH/CoFeP/NF for hydrogen evolution achieves a low overpotential of 198 mV at 50 mA cm−2 in 1.0 M KOH. An overpotential of 269 mV is required at 50 mA cm−2 for oxygen evolution. Meanwhile, the practical utilization of NiFe LDH/CoFeP/NF as bifunctional electrocatalysts for overall water splitting yields 1.73 V at 50 mA cm−2 in the two-electrode cell. Moreover, NiFe LDH/CoFeP/NF can retain over 50 h without an obvious degradation at 10 mA cm−2. The satisfactory operating stability and high activity of NiFe LDH/CoFeP/NF in alkaline solution can be attributed to the heterogeneous layered structure and excellent hydrophilic surface. The study provides a strategy to engineering heterogeneous layered structures with wetting surface for excellent electrocatalytic activities toward overall water splitting. Based on the unique heterogeneous layered structure and superhydrophilic surface, NiFe LDH/CoFeP/NF exhibits excellent catalytic performance and good stability for both hydrogen evolution reaction and oxygen evolution reaction in 1.0 M KOH alkaline solution. [Display omitted] • NiFe LDH/CoFeP/NF requires a cell voltage of 1.73 V at high 50 mA cm−2. • NiFe LDH/CoFeP/NF can retain over 50 h without an obvious decay at 10 mA cm−2. • The heterogeneous layered structure reduces the charge transfer resistance. • The superhydrophilic properties enable electrolyte-electrode contact and reaction. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate whether endoplasmic reticulum (ER) stress is involved in MG-132-induced autophagy, and to determine the effects of the inhibition of autophagy and ER stress on cell viability following MG-132 treatment. The proteasome inhibitor, MG-132, was used to induce autophagy in MCF-7 cells, and 3-methyladenine (3-MA) and salubrinal were used to inhibit autophagy and ER stress, respectively. An MTT assay was used to analyze cell viability. Apoptosis and the cell cycle were analyzed using flow cytometry. The expression levels of apoptosis- and ER stress-associated genes were investigated using western blot and reverse transcription-quantitative polymerase chain reaction analyses. MG-132 inhibited cell proliferation, and induced apoptosis and cell cycle arrest at the G2 phase of the cell cycle. Notably, MG-132 increased the autophagy-associated conversion of microtubule-associated protein 1 light chain 3 (LC3)-I to LC3-II, which was partially attenuated by the ER stress inhibitor, salubrinal. In addition, MG-132 inhibited the protein expression of the anti-apoptotic protein, B-cell lymphoma (Bcl)-2, whereas the expression levels of Bcl-2-associated X protein and caspase-3 were upregulated. These effects were enhanced by co-treatment with either 3-MA or salubrinal. Furthermore, the mRNA and protein levels of the ER stress-associated genes, glucose-regulated protein 78, growth arrest and DNA damage induced gene-153, and caspase-12, were upregulated by MG132, and these levels were significantly inhibited by co-treatment of the cells with salubrinal. Taken together, the results of the present study indicated that the induction of autophagy by the proteasome inhibitor was associated with ER stress in the MCF-7 cells, and that the inhibition of autophagy or ER stress enhanced MG-132-induced apoptosis. These findings suggest the potential application of inhibitors of ER stress and autophagy, in combination with proteasomal inhibitors, for the development of combinatorial targeted cancer therapy. [ABSTRACT FROM AUTHOR]

Aims/Introduction Irisin is a newly identified myokine that can promote energy expenditure. Previous studies showed that circulating urotensin II ( UII) levels were increased in diabetes, and UII could inhibit the glucose transport in skeletal muscle in diabetic mice and aggravated insulin resistance. We presumed that irisin levels are associated with UII in diabetic patients. Materials and Methods A total of 71 patients with type 2 diabetes and 40 healthy subjects were recruited. Blood and urinary irisin concentrations were measured by using enzyme-linked immunosorbent assay, and UII concentrations were measured by bioelectrical impedance analysis. Every participant's body composition was analyzed by bioelectrical impedance. Results The serum irisin levels were significantly lower in diabetic patients than that of controls, whereas serum UII levels were significantly higher in diabetic patients than that in that of controls. Serum irisin levels were negatively associated with circulating UII, hemoglobin A1c and the natural logarithm transformation of urinary albumin excretion, whereas serum irisin was positively associated with estimated glomerular filtration rate, and low-density lipoprotein cholesterol and urinary irisin were positively associated with urinary UII. Furthermore, circulating irisin is positively associated with muscle mass, whereas circulating UII is negatively associated with muscle mass in diabetic patients. Hemoglobin A1c and circulating UII are independent determinants of circulating irisin by multiple regression analysis. Conclusions The present results provide the clinical evidence of an association between irisin and UII in diabetic patients. Hemoglobin A1c and circulating UII are independent determinants of circulating irisin. Our results hint that UII and high glucose might inhibit the release of irisin from skeletal muscle in diabetic patients. [ABSTRACT FROM AUTHOR]

Accidental release of high-pressure hydrogen can result in self-ignition, non-premixed jet flame and high overpressure, which will create potential security risks to people, buildings and equipment. In this study, pressure dynamics and flame induced by the self-combustible hydrogen flowing into the unconfined space were experimentally studied. The entire process was characterized by pressure sensors and cameras. Results show that the velocity of the hydrogen jet increases first and then decreases after it flows out of the tube. Its overpressure decays rapidly and stabilizes quickly. The dramatic changes for the flow field parameters in the near-field region can cause the self-ignition region to extinguish first and then reignite. And the overpressure in the near-field region, caused by the self-ignition jet flowing out of the tube, is lower in the unconfined space than that in the semi-confined space. In addition, axial and radial variations for the jet flame are characterized by phased development, which can be divided into three stages based on features of flame morphology and temperature distribution. Among them, a typical tadpole-like flame is formed. Its head with large size shows asymmetry, develops downward deflection and eventually separates from the flame body which are all affected by asymmetric large-scale vortices. Besides, the re-ignition of the jet can be induced during the nitrogen purge process, which is much more dangerous in real accident scenarios. [ABSTRACT FROM AUTHOR]

Background/Aims: Skeletal muscle atrophy is one of the main manifestations of protein energy wasting. We hypothesized that urotensin II (UII) can lead to skeletal muscle atrophy through upregulating autophagy and affecting Irisin precursor fibronectin type III domain containing 5 (FNDC5) expressions. Methods: Three animal models (the sham operation, wild-type C57BL/6 mice with 5/6 nephrectomy, UII receptor (UT) gene knockout (UTKO) mice with 5/6 nephrectomy) were designed. Skeletal muscle weight, cross-sectional area (CSA) along with UII, FNDC5, LC3, and p62 expression were investigated. C2C12 cells were differentiated for up to 4 days into myotubes. These cells were then exposed to different UII concentrations (10–5 to 10–7 M) for 6–12 h and analyzed for the expressions of autophagic markers. These cells were also exposed to the same predetermined UII concentrations for 48–72 h and analyzed for the FNDC5 expression. Myotube diameter was measured. Results: Upregulation of UII expression in skeletal muscle tissue was accompanied by reduced muscle weight and skeletal muscle CSA in the 2 posterior limbs, upregulated autophagy markers expression, and downregulated FNDC5 expression in 5/6 nephrectomy mice. The decrease of skeletal muscle weight, skeletal muscle CSA, downregulation of FNDC5 expression, and the upregulation of autophagy markers were inhibited in UTKO with 5/6 nephrectomy mice. Our in vitrostudy showed that UII could directly decrease myotube diameter, induce autophagy markers upregulation, and inhibit expression of FNDC5. When UII receptor gene was interfered by UT-specific siRNA, UII induced autophagy markers upregulation and FNDC5 downregulation were inhibited. Conclusion: We are the first to verify UII induces mice skeletal muscle atrophy associated with enhanced skeletal muscle autophagy and inhibited FNDC5 expression in chronic renal failure. [ABSTRACT FROM AUTHOR]

Aims/Introduction: Irisin is a newly identified myokine which can promote energy expenditure. Urotensin II (UII) is identified as the most potent mammalian vasoconstrictor to date. Previous studies showed that UII can aggravate insulin resistance while irisin alleviate insulin resistance. Through this study, it is our aim to elucidate if UII can induce insulin resistance and also have an association with the irisin level in hemodialysis (HD) patients. Materials and Methods: One hundred and twenty-eight patients on maintenance hemodialysis treatment and forty healthy subjects were enrolled in this study. Blood irisin concentrations and UII concentrations were measured by ELISA and RIA respectively. The body composition was analyzed by bioelectrical impedance. Results: The serum irisin levels and UII levels were both significantly lower in HD patients in comparison to that of the healthy subjects. The serum irisin levels were lower in HD patients with protein energy wasting than those of the patients without protein energy wasting. The independent determinants of circulating Ln (irisin) (the natural logarithm of irisin) were UII lean body mass and patients with protein energy wasting. Conclusions: Our results are the first to provide the clinical evidence of the association among irisin, UII, and protein energy wasting. Our results hint that UII and protein energy wasting might inhibit the release or synthesis of irisin from skeletal muscles in HD patients. © 2016 The Author(s) Published by S. Karger AG, Basel [ABSTRACT FROM AUTHOR]