335 research outputs found
CLAYS WITH NO CARBONATES IN BRICK MANUFACTURING: LINK MICROSTRUCTURAL AND MINERALOGICAL EVOLUTION TO FIRING CONDITIONS
Synthetic calcium carbonate improves the effectiveness of treatments with nanolime to contrast decay in highly porous limestone
Three synthetized polymorphs of calcium carbonate have been tested in combination with the suspension of nanolime particles as potential consolidating agents for contrasting stone decay and overcome some of the limitations of nanolime agents when applied to substrates with large porosity. The modifications induced in the pore network of the Maastricht limestone were analyzed with microscopy and in a non-invasive fashion with small angle neutron scattering and synchrotron radiation micro-computed tomography. A reduction in porosity and pore accessibility at the micrometric scale was detected with the latter technique, and ascribed to the improved pore-filling capacity of the consolidation agent containing CaCO3 particles. These were found to be effectively bound to the carbonated nanolime, strengthening the pore-matrix microstructure. Penetration depth and positive effect on porosity were found to depend on the particle size and shape. Absence of significant changes in the fractal nature of the pore surface at the nanoscale, was interpreted as indication of the negligible contribution of nanolime-based materials in the consolidation of stones with large porosity. However, the results indicate that in such cases, their effectiveness may be enhanced when used in combination with CaCO3 particles, owing to the synergic effect of chemical/structural compatibility and particle size distribution
Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine
[This corrects the article DOI: 10.1186/s13054-016-1208-6.]
Periodic Communication Support in Multiple Access Networks Exploiting Token with Timer
A 2-year young adult obesity prevention trial in the US: Process evaluation results
Our objective was to conduct a process evaluation of the CHOICES (Choosing Healthy Options in College Environments and Settings) study, a large, randomized, controlled trial designed to prevent unhealthy weight gain in young adults (aged 18–35) attending 2-year community colleges in the USA. The 24-month intervention consisted of participation in an academic course and a social networking and support website. Among intervention participants, completion rates for most course activities were >80%, reflecting a high level of dose received. Course retention and participant satisfaction were also high. Engagement results, however, were mixed with less than half of participants in the online and hybrid sections of the course reporting that they interacted with course materials ≥3 h/week, but 50–75% reporting that they completed required lessons ‘all/very thoroughly’. Engagement in the website activities was also mixed with more than half of intervention participants logging onto the website during the first month, but then declining to 25–40% during the following 23 months of the intervention. Intervention engagement is a challenge of online interventions and a challenge of working with the young adult age group in general. Additional research is needed to explore strategies to support engagement among this population, particularly for relatively long intervention durations
Keeping the Vimentin Network under Control: Cell–Matrix Adhesion–associated Plectin 1f Affects Cell Shape and Polarity of Fibroblasts
Mature focal adhesions and fibrillar adhesions act as anchorage sites for vimentin filaments, with plectin isoform 1f being the crucial linker protein. Plectin serves as a nucleation and assembly center for the de novo formation of vimentin networks. Anchored vimentin creates a resilient cage-like core structure that affects cell shape
Barnase as a New Therapeutic Agent Triggering Apoptosis in Human Cancer Cells
RNases are currently studied as non-mutagenic alternatives to the harmful DNA-damaging anticancer drugs commonly used in clinical practice. Many mammalian RNases are not potent toxins due to the strong inhibition by ribonuclease inhibitor (RI) presented in the cytoplasm of mammalian cells.In search of new effective anticancer RNases we studied the effects of barnase, a ribonuclease from Bacillus amyloliquefaciens, on human cancer cells. We found that barnase is resistant to RI. In MTT cell viability assay, barnase was cytotoxic to human carcinoma cell lines with half-inhibitory concentrations (IC(50)) ranging from 0.2 to 13 microM and to leukemia cell lines with IC(50) values ranging from 2.4 to 82 microM. Also, we characterized the cytotoxic effects of barnase-based immunoRNase scFv 4D5-dibarnase, which consists of two barnase molecules serially fused to the single-chain variable fragment (scFv) of humanized antibody 4D5 that recognizes the extracellular domain of cancer marker HER2. The scFv 4D5-dibarnase specifically bound to HER2-positive cells and was internalized via receptor-mediated endocytosis. The intracellular localization of internalized scFv 4D5-dibarnase was determined by electronic microscopy. The cytotoxic effect of scFv 4D5-dibarnase on HER2-positive human ovarian carcinoma SKOV-3 cells (IC(50) = 1.8 nM) was three orders of magnitude greater than that of barnase alone. Both barnase and scFv 4D5-dibarnase induced apoptosis in SKOV-3 cells accompanied by internucleosomal chromatin fragmentation, membrane blebbing, the appearance of phosphatidylserine on the outer leaflet of the plasma membrane, and the activation of caspase-3.These results demonstrate that barnase is a potent toxic agent for targeting to cancer cells
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