Search results for " modifica"

Genetic and Cytological Analysis of Drosophila Chromatin-Remodeling Factors

2003

Histone Code and Higher-Order Chromatin Folding: A Hypothesis

2016

AbstractHistone modifications alone or in combination are thought to modulate chromatin structure and function; a concept termed histone code. By combining evidence from several studies, we investigated if the histone code can play a role in higher-order folding of chromatin. Firstly using genomic data, we analyzed associations between histone modifications at the nucleosome level. We could dissect the composition of individual nucleosomes into five predicted clusters of histone modifications. Secondly, by assembling the raw reads of histone modifications at various length scales, we noticed that the histone mark relationships that exist at nucleosome level tend to be maintained at the high…

Mobility Limitation and Changes in Personal Goals Among Older Women.

2016

Objectives. Several theoretical viewpoints suggest that older adults need to modify their personal goals in the face of functional decline. The aim of this study was to investigate longitudinally the association of mobility limitation with changes in personal goals among older women. Method. Eight-year follow-up of 205 women aged 66–78 years at baseline. Results. Health-related goals were the most common at both measurements. Goals related to independent living almost doubled and goals related to exercise and to cultural activities substantially decreased during the follow-up. Higher age decreased the likelihood for engaging in new goals related to cultural activities and disengaging from g…

Giudizio abbreviato

2015

Il rito, ammesso dal giudice su richiesta del solo imputato, attribuisce a quest’ultimo un vero e proprio diritto a rinunciare alle garanzie dibattimentali proprie del giudizio ordinario in cambio dell’effetto premiale previsto in caso di condanna. Il contributo ha un approccio critico mettendo in risalto, dopo una breve storia dell'istituto, le novità introdotte dal legislatore del 1999.

Changes of Structure and Physical-Mechanical Properties in Alloy Steels Thermochemically Treated by Plasma Nitriding

2021

Plasma nitriding is a method of surface modification using a glow discharge technology to introduce nitrogen into the surface of a metal, which subsequently diffuses into the material. The main advantages of plasma nitriding over conventional nitriding processes are: reduced cycle time, controlled growth of the surface layer, elimination of white layer, reduced distortion, no need of finishing, pore-free surfaces and mechanical masks instead of copper plating. The process is especially suitable for complex parts that are intensively solicited by wear, fatigue, contact pressure, shocks, possibly also to corrosion. It is applied in order to bring the metallic products in a state favourable fr…

Nanosecond laser surface modification of AISI 304L stainless steel: Influence the beam overlap on pitting corrosion resistance

2014

Abstract Surface modifications of AISI 304L stainless steel by laser surface melting (LSM) were investigated using a nanosecond pulsed laser-fibre doped by ytterbium at different overlaps. The objective was to study the change in the corrosion properties induced by the treatment of the outer-surface of the stainless steel without modification of the bulk material. Different analytical techniques such as scanning electron microscopy (SEM), X-ray diffraction (XRD), and glow discharge optical emission spectrometry (GDOES) were used to characterize the laser-melted surface. The corrosion resistance was evaluated in a chloride solution at room temperature by electrochemical tests. The results sh…

Evaluation of multifunctional liposomes in human blood serum by light scattering.

2014

To overcome the limited functionality of "stealth" lipids based on linear poly(ethylene glycol) (PEG) chains, hyperbranched polyether-based lipids that bear multiple hydroxyl groups for further chemical modification may be a suitable replacement. This study focuses on the development and characterization of "stealth" liposomes modified with a novel hyperbranched polyglycerol lipid (cholesterol-PEG30-hbPG23). An emphasis was placed on the stability of these liposomes in comparison to those containing a linear PEG derivative (cholesterol-PEG44) directly in human blood serum, characterized via dynamic light scattering (DLS). Polymer lipid contents were varied between 0 and 30 mol %, resulting …

Beyond Poly(ethylene glycol): Linear Polyglycerol as a Multifunctional Polyether for Biomedical and Pharmaceutical Applications

2014

Polyglycerols (sometimes also called "polyglycidols") represent a class of highly biocompatible and multihydroxy-functional polymers that may be considered as a multifunctional analogue of poly(ethylene glycol) (PEG). Various architectures based on a polyglycerol scaffold are feasible depending on the monomer employed. While polymerization of glycidol leads to hyperbranched polyglycerols, the precisely defined linear analogue is obtained by using suitably protected glycidol as a monomer, followed by removal of the protective group in a postpolymerization step. This review summarizes the properties and synthetic approaches toward linear polyglycerols (linPG), which are at present mainly base…

Functionalization of a polyaspartamide with glycidyl methacrylate: A useful method to prepare hydrogels through gamma irradiation

1999

α-β-Poly(N-2-hydroxyethyl)-DL-aspartamide (PHEA) was derivatized with glycidyl methacrylate (GMA). Aqueous solutions of the obtained copolymer PHEA-GMA (PHG) were irradiated by gamma rays with a dose rate of 0.5 KGy/h and at zero °C in the presence or in the absence of N,N'-methylenebisacrylamide (BIS). New hydrogel systems were obtained and characterized by FT-IR analyses and swelling measurements in aqueous medium at different pH values.

New biodegradable hydrogels based on a photo-cross-linkable polyaspartamide and poly(ethylene glycol) derivatives. Release studies of an anticancer d…

2001

The functionalization of α,β-poly(N-2-hydroxyethyl)-dl-aspartamide (PHEA) with glycidyl methacrylate (GMA) gives rise to a water-soluble photosensitive copolymer PHEA-GMA (PHG). Aqueous solutions of PHG alone or in combination with various concentrations of poly(ethylene glycol) dimethacrylate or poly(ethylene glycol) diacrylate (PEGDA) have been exposed to a source of UV rays at 313 nm in order to obtain polymeric networks. All samples have been prepared both as water-swellable microparticles and as gel systems. Microparticles have been characterised by Fourier transform IR spectrophotometry, dimensional analysis and swelling measurements in aqueous media mimicking biological fluids. In vi…