Structural behavior of concrete filled carbon fiber reinforced polymer sheet tube column

In order to examine both static and dynamic behaviors of Concrete Filled Carbon Fiber Reinforced Polymer Sheet Tube (CFCST) columns, experimental tests have been performed. The main variables of this experimental program included the number and wrapping angles of CFRP sheets. Stress versus strain relation of CFCST specimens was investigated by uni-axial tests. And, six full-scaled CFCST columns subjected to quasi-static lateral loading, as well as constant axial compression, were tested. Finally, an analytical procedure to predict the response of CFCST columns subjected to both axial and lateral loadings has been suggested in conjunction with the findings from the experimental tests

Structural behavior of concrete filled carbon fiber reinforced polymer sheet tube column

In order to examine both static and dynamic behaviors of Concrete Filled Carbon Fiber Reinforced Polymer Sheet Tube (CFCST) columns, experimental tests have been performed. The main variables of this experimental program included the number and wrapping angles of CFRP sheets. Stress versus strain relation of CFCST specimens was investigated by uni-axial tests. And, six full-scaled CFCST columns subjected to quasi-static lateral loading, as well as constant axial compression, were tested. Finally, an analytical procedure to predict the response of CFCST columns subjected to both axial and lateral loadings has been suggested in conjunction with the findings from the experimental tests

Growth Kinetics and Optical Properties of CsPbBr3 Perovskite Nanocrystals

We synthesized CsPbBr3 perovskite nanocrystals (NCs) at different reaction temperatures and tracked their growth kinetics on the basis of their optical properties and estimated size. The energies of the absorption and fluorescence (FL) peaks with increasing reaction temperature for the CsPbBr3 perovskite NCs were tuned within the regions of 2.429-2.570 eV and 2.391-2.469 eV, respectively, depending on size of the NCs (9.9-12.5 nm). The Stokes shifts of CsPbBr3 perovskite NCs with increasing NC size decreased from 101 meV to 38 meV. The full-width at half-maximum of the FL peaks for the CdSe NCs decreased from 150 meV to 90 meV because of the improved size uniformity of the CsPbBr3 perovskite NCs. The energy spacing of CsPbBr3 perovskite NCs synthesized at various reaction temperatures was calculated from Tauc plots; this information is critical for determining the bandgap energy and enables the size of the CsPbBr3 perovskite NCs to be estimated using the effective mass approximation

Potential redox-sensitive Akt activation by dopamine activates Bad and promotes cell death in melanocytes

Dopamine (DA) is a well known oxidative neurotoxin. In addition, Akt has been reported to deliver a survival signal that inhibits apoptosis. However, it has also been reported that chronic Akt activation leads to apoptosis in response to oxidative stress. The objective of the present study was to investigate the possible role of the Akt pathway in vitiligo and its possible relationship with DA-induced cell death using Mel-Ab cells. Cultured Mel-Ab cells were treated with DA with and without N-Acetyl-L-cysteine (NAC), which is known to have antioxidative properties. Cell viability was then assessed by a crystal violet assay and Annexin staining was performed. The changes in the expression of Akt were analyzed by western blot analysis. The cell viability was reduced by approximately 60% in response to treatment with 500 µM DA, and NAC effectively prevented this cytotoxic effect. Likewise, treatment with DA produced numerous Annexin positive cells, while treatment with NAC prevented this apoptotic cell death. Akt was slowly phosphorylated after treatment with DA, while NAC clearly inhibited the DA-induced Akt activation. Western blot analysis also showed that treatment with DA induced the activation of Bad. Finally, LY294002 exerted a protective effect against DA-induced apoptotic cell death. DA may induce redox-sensitive Akt activation and increase the level of Bad, which can promote cell death by heterodimerization with survival proteins. Moreover, NAC effectively protects against DA-induced melanocyte death via inhibition of DA-induced Akt activation

Heart Rate Variability and Urinary Catecholamines from Job Stress in Korean Male Manufacturing Workers According to Work Seniority

The aim of this study was to evaluate the relationships between job stress and indicators of autonomic nervous system activity in employees of the manufacturing industry. A total of 140 employees from a company that manufactures consumer goods (i.e., diapers and paper towels) were recruited for participation in this study. Job stress was assessed using Karasek`s Job Content Questionnaire. Heart rate variability (HRV) was measured using a heart rate monitor, and urinary catecholamines were measured by an HPLC-ECD. Information on demographic characteristics, previous job history, smoking status and alcohol consumption was also collected. Job stress did not have a significant effect on HRV or catecholamines. However, low-frequency HRV was significantly higher in the high-strain group of subjects with a short duration of employment. Low- and high-frequency HRV were higher in the high-strain group than in the low-strain group, but these differences were not statistically significant. The results of the present study indicate that low-frequency HRV was significantly higher in the high-strain group of subjects with a short duration of employment. In addition, the results of this study show that HRV can be used as a potential physiologic indicator of job stress in employees with a short duration of employment.Schubert C, 2009, BIOL PSYCHOL, V80, P325, DOI 10.1016/j.biopsycho.2008.11.005Mitoma M, 2008, PROG NEURO-PSYCHOPH, V32, P679, DOI 10.1016/j.pnpbp.2007.11.011Burr RL, 2007, SLEEP, V30, P913Collins SM, 2005, AM J IND MED, V48, P182, DOI 10.1002/ajim.20204Kang MG, 2004, YONSEI MED J, V45, P838Sztajzel J, 2004, SWISS MED WKLY, V134, P514Towa S, 2004, EXP ANIM TOKYO, V53, P137, DOI 10.1538/expanim.53.137Bunker SJ, 2003, MED J AUSTRALIA, V178, P272Peter R, 2002, J EPIDEMIOL COMMUN H, V56, P294VANGELOVA K, 2002, CENT EUR J PUBL HEAL, V10, P149HA M, 2001, STANDARDIZATION DEVvan Amelsvoort LGPM, 2000, INT ARCH OCC ENV HEA, V73, P255Goldstein IB, 1999, PSYCHOSOM MED, V61, P387PIERCECCHIMARTI MD, 1999, MED LAW, V18, P125Sluiter JK, 1998, OCCUP ENVIRON MED, V55, P407KARASEK R, 1998, J OCCUP HEALTH PSYCH, V3, P322ROVERE MTL, 1998, LANCET, V351, P478Sloan RP, 1996, PSYCHOSOM MED, V58, P25VANDERBEEK AJ, 1995, OCCUP ENVIRON MED, V52, P464HUIKURI HV, 1993, CIRCULATION, V87, P1220PAGANI M, 1991, J AUTONOM NERV SYST, V35, P33PAGANI M, 1991, CIRCULATION, V83, P1143PEASTON RT, 1988, J CHROMATOGR-BIOMED, V424, P263

Bacterial Uracil Modulates Drosophila DUOX-Dependent Gut Immunity via Hedgehog-Induced Signaling Endosomes

SummaryGenetic studies in Drosophila have demonstrated that generation of microbicidal reactive oxygen species (ROS) through the NADPH dual oxidase (DUOX) is a first line of defense in the gut epithelia. Bacterial uracil acts as DUOX-activating ligand through poorly understood mechanisms. Here, we show that the Hedgehog (Hh) signaling pathway modulates uracil-induced DUOX activation. Uracil-induced Hh signaling is required for intestinal expression of the calcium-dependent cell adhesion molecule Cadherin 99C (Cad99C) and subsequent Cad99C-dependent formation of endosomes. These endosomes play essential roles in uracil-induced ROS production by acting as signaling platforms for PLCβ/PKC/Ca2+-dependent DUOX activation. Animals with impaired Hh signaling exhibit abolished Cad99C-dependent endosome formation and reduced DUOX activity, resulting in high mortality during enteric infection. Importantly, endosome formation, DUOX activation, and normal host survival are restored by genetic reintroduction of Cad99C into enterocytes, demonstrating the important role for Hh signaling in host resistance to enteric infection

Insulin-inducible SMILE inhibits hepatic gluconeogenesis

The role of a glucagon/cAMP-dependent protein kinase–inducible coactivator PGC-1α signaling pathway is well characterized in hepatic gluconeogenesis. However, an opposing protein kinase B (PKB)/Akt-inducible corepressor signaling pathway is unknown. A previous report has demonstrated that small heterodimer partner–interacting leucine zipper protein (SMILE) regulates the nuclear receptors and transcriptional factors that control hepatic gluconeogenesis. Here, we show that hepatic SMILE expression was induced by feeding in normal mice but not in db/db and high-fat diet (HFD)-fed mice. Interestingly, SMILE expression was induced by insulin in mouse primary hepatocyte and liver. Hepatic SMILE expression was not altered by refeeding in liver-specific insulin receptor knockout (LIRKO) or PKB β-deficient (PKBβ−/−) mice. At the molecular level, SMILE inhibited hepatocyte nuclear factor 4–mediated transcriptional activity via direct competition with PGC-1α. Moreover, ablation of SMILE augmented gluconeogenesis and increased blood glucose levels in mice. Conversely, overexpression of SMILE reduced hepatic gluconeogenic gene expression and ameliorated hyperglycemia and glucose intolerance in db/db and HFD-fed mice. Therefore, SMILE is an insulin-inducible corepressor that suppresses hepatic gluconeogenesis. Small molecules that enhance SMILE expression would have potential for treating hyperglycemia in diabetes

Pathogenicity and antigenicity of a new variant of Korean nephropathogenic infectious bronchitis virus

Despite the existence of an active vaccination program, recently emerged strains of nephropathogenic infectious bronchitis virus (IBV) in Korea have caused significant economic losses in the poultry industry. In this study, we assessed the pathogenic and antigenic characteristics of a K-IIb type field strain of IBV that emerged in Korea since 2003, such as Kr/Q43/06. Specific pathogen free 1-week-old chickens exhibited severe respiratory symptoms (dyspnea) and nephropathogenic lesions (swollen kidneys with nephritis and urate deposits) following challenge with the recent IBV field strain. The antigenic relatedness (R value), based on a calculated virus neutralization index, of the K-IIb type field strain and K-IIa type strain KM91 (isolated in 1991) was 30%, which indicated that the recent strain, Kr/Q43/06, is a new variant that is antigenically distinct from strain KM91. This report is the first to document the emergence of a new antigenic variant of nephropathogenic IBV in chicken from Korea