7,922 research outputs found
Endovenous treatment of the greater saphenous vein using a 1,320 nm Nd:YAG laser causes fewer side effects than using a 940 nm diode laser
Health risks for population living in the neighborhood of a cement factory
In order to assess the health risks associated with the manufacturing of Portland cement for the population living in the neighborhood of a cement industry in Khrew, Kashmir, India, particulate matter and trace gas samplings were done between March and December 2011 in the cement affected area. The main parameters considered for study included suspended particulate matter (SPM), respirable suspended particulate matter (RSPM), non-respirable suspended particulate matter (NRSPM), nitrogen oxides (NOx) and sulfur dioxide (SO2). The population considered most suitable for study was the people residing in 2 - 3 km radius of the cement emission zone and for this, questionnaire based study was performed. The air temperature, air humidity, wind speed, wind direction and light intensity were studied at the sites for the sampling days. The results indicate that there was high level of air pollution with mean SO2 concentration of 115.2 ÎĽg/m3 at site I and 28.13 ÎĽg/m3 at site II when compared. Similarly, Ox concentration at site I was 117.09 ÎĽg/m3 when compared with control site II where it was found to be 19.46 ÎĽg/m3 with high prevalence of diseases particularly, respiratory problems, 97% suffered from eye irritations and 95% suffered from dermatological problems among population living in the neighborhood of cement factory at site I. The assessment of oxidative and nitrosative stress among population was carried out by quantification of ROS and NO levels in serum of subjects. The results show that there was high level of air pollution in the area, adverse health impacts, over production of nitrogen species as well as ROS in subjects residing around cement pollution affected area.Key words: Cement industry, trace gas samplings, human health, dermatological, respiratory problems, eye irritations
Polarization Relaxation Induced by Depolarization Field in Ultrathin Ferroelectric BaTiO Capacitors
Time-dependent polarization relaxation behaviors induced by a depolarization
field were investigated on high-quality ultrathin
SrRuO/BaTiO/SrRuO capacitors. The values were
determined experimentally from an applied external field to stop the net
polarization relaxation. These values agree with those from the electrostatic
calculations, demonstrating that a large inside the ultrathin
ferroelectric layer could cause severe polarization relaxation. For numerous
ferroelectric devices of capacitor configuration, this effect will set a
stricter size limit than the critical thickness issue
Industrial Experience and Disciplinary Knowledge Impact on Creative Outcomes in a Making Context: A Case Study of Graduate Level Industrial Engineering Course
Background: Design and creativity are essential elements of problem-solving. Purpose: The purpose of the research presented herein is to identify the impacts of learning in different study programs on students’ abilities to generate and implement creative design solutions. Design/Method: An experiment was designed and conducted within the context of a semester-long graduate engineering course titled “Human-Centered Design and Manufacturing” at a large American public university. The experiment featured classroom data collection from an experimental cohort at four different stages of an intervention using a questionnaire. Results were then compared to those of a control group’s. Results: Preliminary results showed that students’ systematic creativity learning lessened the differences in creative outcomes due to industrial experience and formal degree program differences. Conclusions: Results from this study could help better prepare students for the ever-increasing interdisciplinary nature of engineering teams in different industrial settings all over the world. The intervention designed for this study will also help students more effectively transition from conceptualizing design concepts, to manufacturing those designs, and finally presenting results to key shareholders
The β-blocker Nebivolol Is a GRK/β-arrestin Biased Agonist
Nebivolol, a third generation β-adrenoceptor (β-AR) antagonist (β-blocker), causes vasodilation by inducing nitric oxide (NO) production. The mechanism via which nebivolol induces NO production remains unknown, resulting in the genesis of much of the controversy regarding the pharmacological action of nebivolol. Carvedilol is another β-blocker that induces NO production. A prominent pharmacological mechanism of carvedilol is biased agonism that is independent of Gαs and involves G protein-coupled receptor kinase (GRK)/β-arrestin signaling with downstream activation of the epidermal growth factor receptor (EGFR) and extracellular signal-regulated kinase (ERK). Due to the pharmacological similarities between nebivolol and carvedilol, we hypothesized that nebivolol is also a GRK/β-arrestin biased agonist. We tested this hypothesis utilizing mouse embryonic fibroblasts (MEFs) that solely express β2-ARs, and HL-1 cardiac myocytes that express β1- and β2-ARs and no detectable β3-ARs. We confirmed previous reports that nebivolol does not significantly alter cAMP levels and thus is not a classical agonist. Moreover, in both cell types, nebivolol induced rapid internalization of β-ARs indicating that nebivolol is also not a classical β-blocker. Furthermore, nebivolol treatment resulted in a time-dependent phosphorylation of ERK that was indistinguishable from carvedilol and similar in duration, but not amplitude, to isoproterenol. Nebivolol-mediated phosphorylation of ERK was sensitive to propranolol (non-selective β-AR-blocker), AG1478 (EGFR inhibitor), indicating that the signaling emanates from β-ARs and involves the EGFR. Furthermore, in MEFs, nebivolol-mediated phosphorylation of ERK was sensitive to pharmacological inhibition of GRK2 as well as siRNA knockdown of β-arrestin 1/2. Additionally, nebivolol induced redistribution of β-arrestin 2 from a diffuse staining pattern into more intense punctate spots. We conclude that nebivolol is a β2-AR, and likely β1-AR, GRK/β-arrestin biased agonist, which suggests that some of the unique clinically beneficial effects of nebivolol may be due to biased agonism at β1- and/or β2-ARs. © 2013 Erickson et al
Synthesis and bioactivities of halogen bearing phenolic chalcones and their corresponding bis Mannich bases.
Phenolic bis Mannich bases having the chemical structure of 1-[3,5-bis-aminomethyl-4-hydroxyphenyl]-3-(4-halogenophenyl)-2-propen-1-ones (1a-c, 2a-c, 3a-c) were synthesized (Numbers 1, 2, and 3 represent fluorine, chlorine, and bromine bearing compounds, respectively, while a, b, and c letters represent the compounds having piperidine, morpholine, and N-methyl piperazine) and their cytotoxic and carbonic anhydrase (CA, EC 4.2.1.1) enzyme inhibitory effects were evaluated. Lead compounds should possess both marked cytotoxic potencies and selective toxicity for tumors. To reflect this potency, PSE values of the compounds were calculated. According to PSE values, the compounds 2b and 3b may serve as lead molecules for further anticancer drug candidate developments. Although the compounds showed a low inhibition potency toward hCA I (25-43%) and hCA II (6-25%) isoforms at 10 μM concentration of inhibitor, the compounds were more selective (1.5-5.2 times) toward hCA I isoenzyme. It seems that the compounds need molecular modifications for the development of better CA inhibitors
Inhibitory effects of benzimidazole containing new phenolic Mannich bases on human carbonic anhydrase isoforms hCA I and II
New phenolic mono and bis Mannich bases incorporating benzimidazole, such as 2-(aminomethyl)-4-(1H-benzimidazol-2-yl)phenol and 2,6-bis(aminomethyl)-4-(1H-benzimidazol-2-yl)phenol were synthesized starting from 4-(1H-benzimidazol-2-yl)phenol. Amines used for the synthesis included dimethylamine, pyrrolidine, piperidine, N-methylpiperazine and morpholine. The CA inhibitory properties of these compounds were tested on the human carbonic anhydrase (CA, EC 4.2.1.1) isoforms hCA I and hCA II. These new compounds, as many phenols show moderate CA inhibitory properties
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