Search results for "BARRIER"
showing 10 items of 678 documents
Porous architecture and thermal properties of thermal barrier coatings deposited by suspension plasma spray
2020
Abstract Besides the intrinsic low heat transfer capability of material, the thermal insulation property of thermal barrier coatings (TBCs) also relies on their microstructures. For better understanding the relationship between process parameters, porous architecture, and thermal properties of coatings, YSZ coatings were firstly manufactured by suspension plasma spray (SPS). Afterwards their total porosities were characterized by using the technique of X-ray transmission, the nano/submicro pores in those coatings were detected with Ultra-Small Angle X-ray Scattering (USAXS), and the thermal properties of coatings were measured using the laser flash method. The results indicated that: i) the…
Lipopolysaccharides and glucagon-like peptide 1 : from molecular mechanisms to pathophysiology
2016
Obesity and type 2 diabetes are metabolic diseases which have reached epidemic proportions worldwide. These metabolic disorders are related to a low grade inflammation whose molecular origin is still unknown. Previous studies have highlighted the involvement of the gut microbiota and especially components of the cell wall of Gram(-) bacteria: lipopolysaccharides (LPS). We have recently shown that LPS enhance glucagon-like peptide 1 (GLP-1) plasma levels, a hormone which is known to stimulate insulin secretion. Moreover there would be a link between the nutritional qualities of food and LPS plasma levels. Thus diet, LPS and GLP-1 may be closely related. The present work focuses on i) the mol…
Comportement en fatigue thermomécanique à haute température d’un système barrière thermique texturé par laser
2020
In service life of Thermal Barrier Coating (TBC) systems for blade applications can be limited by the top-coat (TC) spallation under thermo-mechanical fatigue (TMF) loadings. To improve its TMF life, laser texturing at the bond-coat/top coat interface in the CMSX-4 Plus / γ-γ’ BC/ EB-PVD TC system has been investigated.Thanks to the study of the laser-matter interaction, it seems that the different Ni-based single crystal superalloys have similar laser ablation behaviors and they present almost no sub-surface damage after ablation. Nevertheless, the formation of melted matter near created cavities, possibly recrystallized, is often observed.Different patterns (holes, lines, grids) have been…
In vitro models of blood-brain barrier set by co-culturing primary pericytes, astrocytes and brain capillary endothelial cells
2010
The blood-brain barrier (BBB) is formed by brain capillary endothelial cells (BCECs) under the effects of the brain microenvironment. BCECs are sealed together by tight junctions (TJs) [2]. We previously found that occludin, one of the main TJ components, is correctly localized at the cell periphery only if BCECs are co-cultured with neurons/astrocytes [1-2]. Moreover, pericytes induce PLA2 protein expression through activation of PKCalpha and the MAPK/ERK cascade in immortalized GP8.3 endothelial cells [3]. In the present work, we analyzed the effects of pericytes and/or astrocytes on survival and differentiation of primary endothelial cells, in the presence of a serum-free medium. To test…
Welcome aboard: are birds migrating across the Mediterranean Sea using ships as stopovers during adverse weather conditions?
2022
Birds use stopovers during migration to interrupt endurance flight in order to minimize immediate and/or future fitness costs. Stopovers on ships is considered an exceptional and anecdotal event in the ornithological literature. This does not match the experience we had in the summer of 2021, during an oceanographic campaign in the Central Mediterranean, when we regularly observed on average 2.8 birds, of at least 13 species, stopping on board during the 25 days of the campaign. The median stopping time was 42 min, ranging from a few minutes to overnight stays on board. The probability of finding a bird stopping aboard increased with wind force and cloud cover. Birds also stopped more often…
Barriers to open e-learning in public administrations
2017
The use of Open Educational Resources (OERs) is promising as a complementary resource to traditional e-learning courses. Digital learning resources can be accessed on demand and can be developed by a wide range of employees. Thus, OERs may be suitable as a response to the changing demands of workplace learning. Despite its potential, the uptake of OER is slow. Previous research has found numerous barriers to the use and sharing of OERs, ranging from cultural to technical and organizational challenges. Research has reported barrier concepts, which elaborate on the kinds and meanings of challenges in the educational and private sector domain. Yet, it remains unclear as to why and how barriers…
High barrier properties HDPE/PA6/MMT Films-Preliminary rheological and morphological studies
2007
Facilitators of and Barriers to Sustainable Development in Small and Medium-Sized Enterprises: A Descriptive Exploratory Study in Romania
2021
In the context of growing concerns regarding the deterioration of the environment and the increase in social inequalities, the concept of sustainability emerged as a response of companies, in order to contribute to community goodwill. The drivers and obstacles for the businesses engaging in sustainable policies have been explored at large by scientific literature. However, research gaps were observed, namely regarding SMEs, that tend to have a less formal and more fragmented approach to sustainability. The goal of our study is to determine the main barriers and facilitators for sustainability that Romanian SMEs face, and the connections between them and with the firms’ characteristics. Our …
Barriers and (im)mobility in Rio de Janeiro
2016
In Rio de Janeiro, immobility or the share of people with no journeys on any given day is very high (46%). Immobility has a marked geographical dimension in what is a segregated city. But income has only limited explanatory power. The population structure, with high proportions of people who are not in the labour force and who are unemployed, accounts for the high levels of immobility in the poor districts. Although population structure effects prevail, spatial factors such as the severance effect also account for differences between districts. Indeed, Rio de Janeiro features many different types of barriers that affect immobility in several districts and for several population groups. The…
Kontiolahtelaisten nuorten toiveet kunnan liikuntapaikoista ja -palveluista
2017
Lauri Kontkanen (2017). Kontiolahtelaisten nuorten toiveet kunnan liikuntapaikoista ja - palveluista. Liikuntapedagogiikan pro gradu -tutkielma. Liikuntatieteellinen tiedekunta. Jyväskylän yliopisto, 68 s, 1 liite. Tausta. Pro gradu -tutkielman tavoitteena oli tutkia nuorten liikuntapaikka ja -palvelutoiveita Kontiolahdella. Tutkimuksessa selvitettiin, mitkä ovat nuorten eniten harrastamat liikuntalajit, ja missä liikuntaseuroissa he liikkuivat. Lisäksi tutkimuksessa tarkasteltiin liikunnan harrastamisen esteitä. Tutkimukseni on jatkoa syksyllä 2013 valmistuneelle Kontiolahden liikuntapaikkasuunnitelmalle, jonka sain kunnalta tehtäväksi. Tässä tutkimuksessa on tarkoitus syventää tietoa last…