112 research outputs found
Seismic rehabilitation of cultural heritage masonry buildings with unbonded fiber reinforced elastomeric isolators (U-FREIs) \u2013 A case of study
In order to assess the structural behavior and to evaluate the seismic vulnerability of masonry structuresof relevant historical and artistic significance, which is a widespread building type in Italy and in the world,an historical masonry church is analyzed under earthquake loading. Linear and non-linear analyses areperformed on the finite element models of the structure. From these analyses it is pointed out that thestructure does not behave elastically in its existing condition even when subjected to the frequent designearthquake (81% probability of being exceeded over 50 years). Two traditional rehabilitation methods arestudied: the placement of a rigid diaphragm which connects the top of the masonry walls only enclosingthe church entrance area and the placement of a rigid diaphragm which connects the tops of all masonrywalls. None of the traditional method is sufficient for the structure to survive basic design earthquake(10% probability of being exceeded over 50 years). Hence an advanced seismic retrofit solution usinginnovative carbon fiber reinforced elastomeric isolators is proposed. The proposed intervention consistsin the installation of six Unbonded Fiber-Reinforced Elastomeric Isolators (U-FREI) and six Flat SurfaceSliders (FSS) as passive protective devices besides the placement of a rigid diaphragm which connects thetops of all masonry walls. The process of installation of the devices is illustrated. The use of the proposedsolution leads to a remarkable enhancement of the seismic response capacities of the structure; indeeda general elastic response under the Basic Design Earthquake (BDE) is attained
A meso-scale model of progressive damage and failure in LSI-produced ceramic matrix composites for aerospace applications
Structural Characterization and Lifetimes of Triple‐Stranded Helical Coinage Metal Complexes: Synthesis, Spectroscopy and Quantum Chemical Calculations
This work reports on a series of polynuclear complexes containing a trinuclear Cu, Ag, or Au core in combination with the fac-isomer of the metalloligand [Ru(pypzH)](PF) (pypzH=3-(pyridin-2-yl)pyrazole). These (in case of the Ag and Au containing species) newly synthesized compounds of the general formula [{Ru(pypz)}M](PF) (2: M=Cu; 3: M=Ag; 4: M=Au) contain triple-stranded helical structures in which two ruthenium moieties are connected by three N-M-N (M=Cu, Ag, Au) bridges. In order to obtain a detailed description of the structure both in the electronic ground and excited states, extensive spectroscopic and quantum chemical calculations are applied. The equilateral coinage metal core triangle in the electronic ground state of 2–4 is distorted in the triplet state. Furthermore, the analyses offer a detailed description of electronic excitations. By using time-resolved IR spectroscopy from the microsecond down to the nanosecond regime, both the vibrational spectra and the lifetime of the lowest lying electronically excited triplet state can be determined. The lifetimes of these almost only non-radiative triplet states of 2–4 show an unusual effect in a way that the Au-containing complex 4 has a lifetime which is by more than a factor of five longer than in case of the Cu complex 2. Thus, the coinage metals have a significant effect on the electronically excited state, which is localized on a pypz ligand coordinated to the Ru atom indicating an unusual cooperative effect between two moieties of the complex
Surgical Decision-Making in Spinal Instability in Facioscapulohumeral Muscular Dystrophy Related with a Spinal Muscle Atrophy
No abstract availabl
European overview of sustainable policies and approaches in COST C25 member countries
The implementation of the principles and methods towards a Sustainable Construction varies
across different countries in Europe. In some countries, the sustainability of the construction
sector has been effectively taken into consideration over the last years, while in other its implementation
is at an initial stage. Many reasons may be pointed out for this situation. Different
countries have different understandings of what is entailed in Sustainable Construction. Different
cultural and educational backgrounds, along with different priorities in each country, are
also contributing for the lack of a common European approach.
General frameworks, aiming to cover every aspect of Sustainable Construction and to provide
a consistent and integrated approach, such as Agenda 21 for Sustainable Construction,
gave a major advance in the search for a common approach for the construction sector. However,
general agreed methodologies and tools to make this common approach operational are
still missing.European Science Foundation - COST Action C2
Association of TGFβ1, TNFα, CCR2 and CCR5 gene polymorphisms in type-2 diabetes and renal insufficiency among Asian Indians
BACKGROUND: Cytokines play an important role in the development of diabetic chronic renal insufficiency (CRI). Transforming growth factor β1 (TGF β1) induces renal hypertrophy and fibrosis, and cytokines like tumor necrosis factor-alpha (TNFα), chemoattractant protein-1 (MCP-1), and regulated upon activation and normal T cell expressed and secreted (RANTES) mediate macrophage infiltration into kidney. Over expression of these chemokines leads to glomerulosclerosis and interstitial fibrosis. The effect of MCP-1 and RANTES on kidney is conferred by their receptors i.e., chemokine receptor (CCR)-2 and CCR-5 respectively. We tested association of nine single nucleotide polymorphisms (SNPs) from TGFβ1, TNFα, CCR2 and CCR5 genes among individuals with type-2 diabetes with and without renal insufficiency. METHODS: Type-2 diabetes subjects with chronic renal insufficiency (serum creatinine ≥ 3.0 mg/dl) constituted the cases, and matched individuals with diabetes of duration ≥ 10 years and normoalbuminuria were evaluated as controls from four centres in India. Allelic and genotypic contributions of nine SNPs from TGFβ1, TNFα, CCR2 and CCR5 genes to diabetic CRI were tested by computing odds ratio (OR) and 95% confidence intervals (CI). Sub-analysis of CRI cases diabetic retinopathy status as dependent variable and SNP genotypes as independent variable in a univariate logistic regression was also performed. RESULTS: SNPs Tyr81His and Thr263Ile in TGF β1 gene were monomorphic, and Arg25Pro in TGF β1 gene and Δ32 polymorphism in CCR5 gene were minor variants (minor allele frequency <0.05) and therefore were not considered for case-control analysis. A significant allelic association of 59029G>A SNP of CCR5 gene has been observed and the allele 59029A seems to confer predisposition to development of diabetic CRI (OR 1.39; CI 1.04–1.84). In CRI subjects a compound group of genotypes "GA and AA" of SNP G>A -800 was found to confer predisposition for proliferative retinopathy (OR 3.03; CI 1.08–8.50, p = 0.035). CONCLUSION: Of the various cytokine gene polymorphisms tested, allele 59029A of CCR5 gene is significantly associated with diabetic renal insufficiency among Asian Indians. Result obtained for 59029G>A SNP of CCR5 gene is in conformity with reports from a Japanese population but due to sub-optimal power of the sample, replication in larger sample set is warranted
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