Search results for "MICI"
showing 10 items of 1671 documents
Environment- and sequence-dependent modulation of the double-stranded to single-stranded conformational transition of gramicidin A in membranes.
1998
The role of the membrane lipid composition and the individual Trp residues in the conformational rearrangement of gramicidin A along the folding pathway to its channel conformation has been examined in phospholipid bilayers by means of previously described size-exclusion high-performance liquid chromatography HPLC-based strategy (Bano et al. (1991) Biochemistry 30, 886). It has been demonstrated that the chemical composition of the membrane influences the transition rate of the peptide rearrangement from double-stranded dimers to beta-helical monomers. The chemical modification of Trp residues, or its substitution by the more hydrophobic residues phenylalanine or naphthylalanine, stabilized…
Size-exclusion high-performance liquid chromatography in the study of the autoassociating antibiotic gramicidin A in micellar milieu.
2003
Gramicidin A (gA) is a polypeptide antibiotic which forms dimeric channels specific for monovalent cations in biological membranes. It is a polymorphic molecule that adopts several different conformations, double-stranded (ds) helical dimers (pore conformation) and single-stranded beta-helical dimers (channel conformation). This study investigated the conformational adaptability of gramicidin A when incorporated into micelles as membrane-mimetic model system. Taking advantage of our reported, versatile, size-exclusion high-performance liquid chromatography (SE-HPLC) strategy that allows the separation of double-stranded dimers and monomers, we have quantitatively characterized the conformat…
Citrate-nitrate auto-combustion synthesis of perovskite-type nanopowders: A systematic approach
2009
Genotoxicity of citrus wastewater in prokaryotic and eukaryotic cells and efficiency of heterogeneous photocatalysis by TiO(2).
2012
Abstract The presence of (±)α-pinene, (+)β-pinene, (+)3-carene, and R-(+)limonene terpenes in wastewater of a citrus transformation factory was detected and analyzed, in a previous study, by using Solid Phase Micro-extraction (SPME) followed by GC analyses. Purpose of that research was to compare the genotoxic responses of mixtures of terpenes with the genotoxicity of the individual compounds, and the biological effects of actual wastewater. Genotoxicity was evaluated in the Salmonella reversion assay (Ames test) and in V79 cells by Comet assay. Ames tests indicated that the four single terpenes did not induce an increase of revertants frequency. On the contrary, the mixtures of terpenes ca…
Le città come attori dello sviluppo
2017
Il capitolo parte dal considerare la nuova centralità che le città hanno assunto nella fase attuale del capitalismo e le ragioni di tale centralità. Vengono poi ripercorsi e descritti alcuni modelli teorici di riferimento con cui la letteratura ha studiato il ruolo delle città nei processi di crescita e in particolare viene fatto riferimento al modello di città creativa, a quello di città globale e al modello di città europea. Il capitolo infine prende in considerazione esempi di ricerca applicata che utilizzano i modelli teorici presentati e discussi.
Supporting Dispute Handling in E-Commerce Transactions, a Framework and Related Methodologies
2004
An E-commerce transaction is a means to conduct particular commercial activities using the global digital E-commerce infrastructure. We concentrate here on business to customer (B-to-C) E-commerce transactions. These transactions are based on protocols offered by the global infrastructure, primarily the Internet. Using electronic means to do business can greatly improve the efficiency of the business transactions. It, however, poses some problems that were rarely considered to be important before. One class of problems is caused by the behavior of untrusted participants. For reasons such as dishonesty, disputes may arise. In the general case, when a dispute arises an untrustworthy participa…
Salinity gradient engines
2016
Abstract This chapter is devoted to the description of a new class of heat engines based on salinity gradient technology and able to convert low-grade heat into power. The salinity gradient power (SGP) process is employed within a closed loop composed of two different sections: (i) the SGP unit devoted to the energy production, and (ii) a regeneration unit fed by the solutions exiting from the SGP unit and able to restore the initial concentration, thus regenerating the salinity gradient. The main features, limits and perspectives of this novel heat engine are described along with an overview of the state of the art presented in the literature and an example of exergetic analysis of the cyc…
Reverse electrodialysis heat engine for sustainable power production
2017
Abstract Reverse Electrodialysis Heat Engine (REDHE) is a promising technology to convert waste heat at temperatures lower than 100 °C into electric power. In the present work an overview of the possible regeneration methods is presented and the technological challenges for the development of the RED Heat Engine (REDHE) are identified. The potential of this power production cycle was investigated through a simplified mathematical model. In the first part of the work, several salts were singularly modelled as possible solutes in aqueous solutions feeding the RED unit and the corresponding optimal conditions were recognized via an optimization study. In the second part, three different RED He…
Successful control of an outbreak of colonization by Klebsiella pneumoniae carbapenemase-producing K. pneumoniae sequence type 258 in a neonatal inte…
2013
This article reports an outbreak of colonization by Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-Kp) sequence type (ST) 258 in a neonatal intensive care unit (NICU) in Palermo, Italy. KPC-Kp ST258 was detected by an active surveillance culture programme. Between 18th September and 14th November 2012, KPC-Kp was isolated from 10 out of 54 neonates admitted in the outbreak period. No cases of infection were recorded. Male sex was associated with colonization, whereas administration of ampicilline-sulbactam plus gentamicin was protective. Infection control interventions interrupted the spread of KPC-Kp without the need to close the NICU to new admissions. (C) 2013 The Healt…