1,173 research outputs found

    Effect of secondary thermal treatment on crystallinity of spinel-type Co(Cr, Al)2O4 pigments synthesized by solution combustion route

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    The effect of a post-synthesis thermal treatment on CoCr2−2ΨAl2ΨO4 (0.0 ≤ Ψ ≤ 1.0) ceramic pigments synthesized by Solution Combustion Synthesis (SCS) has been studied. As-synthesized SCS pigments were treated at two different calcination temperatures (800 °C and 1000 °C) to study changes in mineralogy, microstructure and thermal behaviour, as well as their effect over the colouring power. Spinel-type Fd-3m crystalline structure was developed in all cases. Nevertheless, crystallinity parameters were highly affected by both analysed processing parameters: composition (Ψ) and post-synthesis calcination temperature (Tc). A Cr(III) enrichment along with Tc increase favoured ion rearrangement to promote sample crystallization and crystallite growth. Fast kinetics of SCS makes Al-rich spinels with transition metals difficult to be synthesized. The application of a secondary thermal treatment resulted in a favourable evolution towards a well-crystallized structure. Lattice parameter did not seem to be affected by Tc, although it evolved indeed with composition. From a microstructural point of view, as-synthesized pigments were foamy, with a very low bulk density and nanometric grain size. After the thermal treatment, larger grain sizes were obtained, especially for the samples richer in Al and treated at higher Tc. All pigments developed intense colours in a transparent glaze without showing heterogeneities, indicating a stable behaviour against glazing process. Glaze colour evolved from green to perfectly blue shades, indicating an important dependence on composition. Nevertheless, colouring power seemed to be rather affected by calcination process

    Bioactive ceramic coating solution for offshore floating wind farms

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    Biofouling is a natural phenomenon that consists of the accumulation of living organisms on an artificial surface submerged or in contact with water like Offshore platforms. This study highlights the need for offshore floating wind farms structures to consider the choice of material used in offshore applications to minimize microbial-associated and corrosion problems. For this purpose, differences in the total of seawater biofouling attached on two coated paints and three ceramic coatings in carbon steel for offshore structures were evaluated and compared. All ceramic coatings were made of incorporating, by electrophoretic deposition, active ceramic particles against biofouling as copper, silver, zinc and titanium. This experiment consisted of testing ceramic coatings and conventional paints in a real environment with high biological activity and at the same time in a shallow marine environment for a period of 1 year, which provided positive comparisons with the standard system (ASTM-D3623) for using in protecting offshore marine structures

    Antifouling and anticorrosive protection of renewable energy marine structures with TiO2-based enamel

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    Biofouling is a significant problem that affects renewable energy marine structures (REMS), such as wind turbines and those designed for wave or tidal energy exploitation. Marine organisms, including algae, barnacles, and mollusks, attach themselves to the surface of these structures, which can lead to reduced efficiency and increased maintenance costs. In addition, biofouling can also cause corrosion, which can compromise the structural integrity of the offshore platforms. To combat this problem, several methods have been developed, including anti-fouling coatings, physical methods, and biological methods. Each method has its advantages and disadvantages, and the most effective solution often depends on the specific type of fouling and the location of the offshore structure. Effective biofouling prevention is essential for the safe and efficient operation of offshore structures and the protection of marine ecosystems. To prevent the spread of invasive species, an innovative ceramic coating has been designed and tested in accordance with ASTM-D3623 procedure. The investigation results revealed that, after four years of experimentation in a real environment, the biofouling growth observed in the splash zone of the antifouling paint was 129.76% higher than that of the titanium-based ceramic coating and it is expected that this difference will continue to grow over time

    Expression of Smac/Diablo in tubular epithelial cells and during acute renal failure

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    Expression of Smac/Diablo in tubular epithelial cells and during acute renal failure.BackgroundApoptosis contributes to tubular cell loss in the course of renal injury. However, the mechanisms regulating tubular cell apoptosis are not well understood. Smac/Diablo is a mitochondrial protein that is released to the cytosol during apoptosis, where it blocks the antiapoptotic activity of inhibitor of apoptosis proteins (IAPs).MethodsWe have studied the regulation of Smac/Diablo mRNA and protein expression in murine toxic acute tubular necrosis, and in cultured tubular epithelial cells exposed to the lethal cytokine tumor necrosis factor (TNF).ResultsFolic acid–induced acute renal failure was associated with tubular cell apoptosis. Smac/Diablo mRNA and protein levels increased by 50% at 24 hours. TNF, a cytokine whose renal expression increases in folic acid nephropathy, induced apoptosis in cultured tubular epithelial cells in a time-dependent manner. In addition, TNF increased the mRNA and protein expression of Smac/Diablo.ConclusionThese findings support the concept that regulation of Smac/Diablo mRNA and protein expression is a mechanism by which lethal stimuli amplify their lethal potential in renal cells

    Impulsivity in fatal suicide behaviour: A systematic review and meta-analysis of psychological autopsy studies

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    Our aim is to review and perform a meta-analysis on the role of impulsivity in fatal suicide behaviour. We included papers who used psychological autopsy methodology, assessed adult death by suicide, and included assessment of impulsivity. We excluded papers about assisted suicide, terrorist suicide, or other cause of death other than suicide or postmortem diagnosis made only from medical records or database. 97 articles were identified. 33 were included in the systematic review and nine in the meta-analysis. We found that people who die by suicide with high impulsivity are associated with younger age, substance abuse, and low intention to die, whereas those with low impulsivity were associated with older age, depression, schizophrenia, high intention to die and low social support. In the meta-analysis, suicide cases had higher impulsivity scores than living controls (Hedges' g = 0.59, 95 % CI [0.28, 0.89], p=.002). However, studies showed heterogeneity (Q = 90.86, p<.001, I2=89.0 %). Impulsivity-aggressiveness interaction was assessed through meta-regression (β=0.447, p=.045). Individuals with high impulsivity would be exposed to a higher risk of fatal suicide behaviour, aggressiveness would play a mediating role. People who die by suicide with high and low impulsivity display distinct characteristics, which may reflect different endophenotypes leading to suicide by different pathways

    IFE Plant Technology Overview and contribution to HiPER proposal

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    HiPER is the European Project for Laser Fusion that has been able to join 26 institutions and signed under formal government agreement by 6 countries inside the ESFRI Program of the European Union (EU). The project is already extended by EU for two years more (until 2013) after its first preparatory phase from 2008. A large work has been developed in different areas to arrive to a design of repetitive operation of Laser Fusion Reactor, and decisions are envisioned in the next phase of Technology Development or Risk Reduction for Engineering or Power Plant facilities (or both). Chamber design has been very much completed for Engineering phase and starting of preliminary options for Reactor Power Plant have been established and review here

    Analysis of multipactor RF breakdown in a waveguide containing a transversely magnetized ferrite

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    In this paper, the multipactor RF breakdown in a parallel-plate waveguide partially filled with a ferrite slab magnetized normal to the metallic plates is studied. An external magnetic field is applied along the vertical direction between the plates in order to magnetize the ferrite. Numerical simulations using an in-house 3D code are carried out to obtain the multipactor RF voltage threshold in this kind of structures. The presented results show that the multipactor RF voltage threshold at certain frequencies becomes considerably lower than for the corresponding classical metallic parallel-plate waveguide with the same vacuum gap.This work was supported by the European Space Agency (ESA) under Novel Investigation in Multipactor Effect in Ferrite and other Dielectrics used in high power RF Space Hardware Contract AO 1-7551/13/NL/GLC, and partially by the Spanish Government (under coordinated R&D projects TEC2013-47037-C5-R and TEC2014-55463-C3-3-P)

    Mitogen-Activated Protein Kinase 14 Promotes AKI

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    An improved understanding of pathogenic pathways may identify novel acute kidney injury (AKI) therapeutic approaches. Unbiased LC-MS/MS protein expression profiling combined with focused data mining identified MAP3K14 and non-canonical NFκB activation at the crossroads of the enriched pathways MAPK, ubiquitin-mediated proteolysis, chemokines, NFκB and apoptosis in the kidney cortex of experimental toxic AKI. In AKI the upstream kinase MAP3K14, the NFκB DNA binding heterodimer RelB/NFκB2, and proteins involved in NFκB2 p100 ubiquitination and proteasomal processing to p52, such as Ube2m and cullin1 were up-regulated. Immunohistochemistry localized MAP3K14 expression to tubular cells in experimental and human AKI. In vivo evidence of MAP3K14 activation in experimental folic acid-induced AKI consisted of NFκB2 p100 processing to p52, nuclear location and DNA binding of RelB and NFκB2. MAP3K14 activity-deficient aly/aly mice were protected from kidney dysfunction, inflammation and apoptosis in AKI induced by folic acid and from lethality in cisplatin-induced AKI. MAP3K14 siRNA targeting in cultured tubular cells decreased inflammation and cell death. Bone marrow transplantation experiments where consistent with a protective effect of renal cell MAP3K14 targeting. Cell culture and in vivo studies identified chemokines MCP-1, RANTES and CXCL10 as MAP3K14 targets in tubular cells, thus identifying potential mediators of the deleterious effect of MAP3K14 in kidney injury. In conclusion, MAP3K14 promotes kidney injury through promotion of inflammation and cell death and is a promising novel therapeutic target

    Novel multipactor studies in RF satellite payloads: Single-carrier digital modulated signals and ferrite materials

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    In this work it is reviewed the most novel advances in the multipactor RF breakdown risk assessment devoted to RF satellite microwave passive devices employed in space telecommunication systems. On one side, it is studied the effect of transmitting a single-carrier digital modulated signal in the multipactor RF voltage threshold in a coaxial line. On the other hand, an analysis of the multipactor phenomenon in a parallel-plate waveguide containing a magnetized ferrite slab it is presented

    Pathogenic pathways and therapeutic approaches targeting inflammation in diabetic nephropathy

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    Diabetic nephropathy (DN) is associated with an increased morbidity and mortality, resulting in elevated cost for public health systems. DN is the main cause of chronic kidney disease (CKD) and its incidence increases the number of patients that develop the end-stage renal disease (ESRD). There are growing epidemiological and preclinical evidence about the close relationship between inflammatory response and the occurrence and progression of DN. Several antiinflammatory strategies targeting specific inflammatory mediators (cell adhesion molecules, chemokines and cytokines) and intracellular signaling pathways have shown beneficial effects in experimental models of DN, decreasing proteinuria and renal lesions. A number of inflammatory molecules have been shown useful to identify diabetic patients at high risk of developing renal complications. In this review, we focus on the key role of inflammation in the genesis and progression of DN, with a special interest in effector molecules and activated intracellular pathways leading to renal damage, as well as a comprehensive update of new therapeutic strategies targeting inflammation to prevent and/or retard renal injury.The authors work has been supported by grants from Instituto de Salud Carlos III (ISCIII, FIS-FEDER PI17/00130, PI17/01495, PI19/00588, ERA-PerMed-JTC2018-PERSTIGAN AC18/00071), Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM) and Cardiovascular (CIBERCV), Fondecyt Project (No. 1160465), Spanish Ministry of Science and Innovation (RTI2018-098788-B-100, DTS17/00203, DTS19/00093, RYC-2017-22369), and Spanish Societies of Cardiology (SEC), Nephrology (SEN) and Atherosclerosis (SEA). The “PFIS” and “Sara Borrell” training program of the ISCIII supported the salary of MGH (FI18/00310), SR-M (CD19/00021) and CH-B (CP16/00017). Córdoba University supported the salary of C.G.C
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