Search results for "oxides"

Air pollution in European countries and life expectancy—modelling with the use of neural network

2019

Abstract The present paper discusses a novel methodology based on neural network to determine air pollutants’ correlation with life expectancy in European countries. The models were developed using historical data from the period 1992–2016, for a set of 20 European countries. The subject of the analysis included the input variables of the following air pollutants: sulphur oxides, nitrogen oxides, carbon monoxide, particulate matters, polycyclic aromatic hydrocarbons and non-methane volatile organic compounds. Our main findings indicate that all the variables significantly affect life expectancy. Sensitivity of constructed neural networks to pollutants proved to be particularly important in …

Influences of atomization process and precursor material on the compaction mechanisms and metallurgical properties of parts developed by HIP

2022

Hot Isostatic pressing process is based on the densification of metals powders to near net shape parts with higher mechanicals properties than forged chemical equivalent. The precursor material can influence the parts properties. Thus the aims of this these is to understand the influence of the powder properties on the HIP parts. The particles characterization and the elements and compound monitoring during the HIP cycle allowed to understand the different oxidations phenomenons and their impact on the mechanical properties of parts. The comparison of differents powders batches with identical particles size repartition or identical chemical composition showed that the chemical composition a…

A Ferromagnetic [Cu3(OH)2]4+Cluster Formed inside a Tritopic Nonaazapyridinophane: Crystal Structure and Solution Studies

2009

Impedance investigation of BaCe0.85Y0.15O3-delta properties for hydrogen conductor in fuel cells

2012

International audience; The influence of the sintering conditions on the electrochemical properties of the proton conducting electrolyte BaCe0.85Y0.15O3-delta (BCY15) and Ni - based BCY15 cermet anode for application in high temperature proton conducting fuel cell are investigated by electrochemical impedance spectroscopy. The results show that at lower sintering temperatures due to the formation of parasitic Y2O3 phase an increase of both the electrolyte and electrode resistances is observed. This effect is strongly reduced by enhancement of the sintering temperature. The obtained BCY15 conductivity (sigma = 2.5x10(-2) S/cm at 700 degrees C) is comparable with that of the best proton condu…

Influence of the pH on the synthesis of reduced graphene oxide under hydrothermal conditions

2012

Here we describe the important role played by the pH on the morphology and structure of the reduced graphite oxide (rGO) samples obtained by hydrothermal treatment of the previously prepared GO. The nature of the resulting samples has been studied on the basis of a complete battery of experimental techniques.

Influence of a bioceramic root end material and mineral trioxide aggregates on fibroblasts and osteoblasts

2012

The biocompatibility of materials used in endodontic treatment is of high importance, because they can come in contact with periradicular tissues and there is a risk of possible systemic toxicity. The aim of the present study was to investigate the in vitro reaction to a bioceramic based root end material in comparison to mineral trioxide aggregates (MTA) as the established gold standard.The root end materials grey MTA Angelus (GMTA), white MTA Angelus (WMTA), ProRoot MTA, and EndoSequence Root Repair Material (ERRM) were incubated with human periodontal ligament fibroblasts and osteoblasts (10(4)cells/ml) for up to 96h. Cell proliferation (RFU) was determined by means of the Alamar Blue as…

Heme oxygenase-1 induction by nitric oxide in RAW 264.7 macrophages is upregulated by a cyclo-oxygenase-2 inhibitor.

2001

Unstimulated RAW 264.7 macrophages express negligible heme oxygenase-1 (HO-1) protein but incubation with the nitric oxide (NO) donor spermine nonoate (SPNO) induced HO-1 and weakly cyclo-oxygenase-2 (COX-2) protein. This effect was potentiated by coincubation with the COX-2 selective inhibitor, SC58125. Cells incubated with SPNO showed a strong increase in HO-1 mRNA levels after 4 h with a significant potentiation in the presence of SC58125, which did not modify HO-1 mRNA stability. The induction of HO-1 by NO and its potentiation by anti-inflammatory agents may play a role in inflammatory and immune responses.

Postnatal overfeeding in rats leads to moderate overweight and to cardiometabolic and oxidative alterations in adulthood.

2011

In contrast to the masses of data on obesity, few data are available concerning the cardiometabolic and oxidative consequences of moderate overweight. The model of postnatal overfeeding (OF) induces an increase in body weight at weaning that remains during adult life. Litters of Wistar rats were either maintained at 12 pups (normal-fed group, NF), or reduced to 3 pups at birth in order to induce OF. At 6 months of age, metabolic parameters, circulating oxidative stress and aortic and coronary vasoreactivity were assessed. Cardiac susceptibility to ischemia-reperfusion injury was also evaluated ex vivo as were markers of cardiac remodeling. OF led to an increase in body weight at weaning (+5…

Effects of marine 2-polyprenyl-1,4-hydroquinones on phospholipase A2 activity and some inflammatory responses.

1995

Three 2-polyprenyl-1,4-hydroquinone derivatives (2-heptaprenyl-1,4-hydroquinone: IS1, 2-octaprenyl-1,4-hydroquinone: IS2 and 2-[24-hydroxy]-octaprenyl-1,4-hydroquinone: IS3) isolated from the Mediterranean sponge Ircinia spinosula, were evaluated for effects on phospholipase A2 activity of different origin (Naja naja venom, human recombinant synovial fluid and bee venom), as well as on human neutrophil function and mouse ear oedema induced by 12-O-tetradecanoylphorbol 13-acetate (TPA). IS1 interacted minimally with these responses. In contrast, IS2 and IS3 inhibited human recombinant synovial phospholipase A2 in a concentration-dependent manner, with minor effects on the rest of the enzymes…

A single loading dose of clopidogrel causes dose-dependent improvement of endothelial dysfunction in patients with stable coronary artery disease: Re…

2006

Clinical studies have demonstrated beneficial effects for clopidogrel in patients with atherothrombotic disease. Recent in vitro studies identified stimulating effects of clopidogrel on endothelial cells, pointing towards mechanisms of action beyond the inhibition of platelet aggregation. We hypothesized that in vivo use of clopidogrel improves endothelial dysfunction in patients with coronary artery disease (CAD). Fifty-eight patients with CAD were randomly assigned to double-blinded oral administration of one single dose of clopidogrel 300 mg (C300) or 600 mg (C600), respectively. Endothelial function was assessed by measurement of flow-mediated dilation (FMD) of the brachial artery befor…