Physical characterization of Ge films on polyethylene obtained by pulsed laser deposition

A Nd:YAg laser, operating in fundamental wavelength at 1064 nm, is focused at an intensity of the order of 10¹⁰ W/cm² to ablate a solid Ge target. A Laser Ion Source (LIS) system is employed to produce ion emission at high directionality, high current, high rate of production and high charge states.     

Mass spectrometry detection as an innovative and advantageous tool in ligand exchange capillary electrophoresis

The copper(II) complex of a modified cyclodextrin, namely 6-mono-deoxy-6-[4-(2-aminoethyl)imidazolyl]-β-CD (CDmh), previously synthesized and characterized in our laboratory and already used as chiral selector for ligand exchange capillary electrophoresis (LECE) with optical detection, is investigated here in LECE using electrospray-mass spectrometry (ESI-MS) as the detection device. The potential of this hyphenated method is compared with the results previously obtained with optical detection by studying the chiral resolution of tryptophan racemate. Chiral separation conditions compatible with LECE-ESI-MS could be achieved based on the figures of merit obtained by LECE-UV. Interestingly, the values of LOD obtained by LECE-ESI-MS were significantly better than those obtained by LECE-UV and thus, ESI-MS detection seems to open new perspectives in chiral separations by LECE.     

Interaction of naproxen amphiphilic derivatives with biomembrane models evaluated by differential scanning calorimetry and Langmuir-Blodgett studies

Anti-inflammatory drugs represent a potential new strategy for the treatment of Alzheimer's disease (AD). The ability to cross the blood-brain barrier and to reach brain tissues is a critical point for these drugs and is strictly related to their lipophilicity. Naproxen (NAP) is a non-steroidal anti-inflammatory drug (NSAIDs) under active investigation for AD. To improve its lipophilic character, NAP was conjugated through a diethylamine spacer (EDA) to lipoamino acids (LAA), α-amino acids containing a long alkyl side chain, to obtain the NAP-EDA-LAA10 and NAP-EDA-LAA14 prodrugs. The interaction of NAP and prodrugs with dimyristoylphosphatidylcholine phospholipids, forming either multilamellar vesicles or monolayers (at the air/water interface) and used as biomembrane models, was studied by differential scanning calorimetry and Langmuir-Blodgett techniques. Experimental data showed that NAP conjugation with LAA residues was able to enhance the drug interaction with such biomembrane models.     

4‐[4‐(Di­methyl­amino)­benzyl­idene­amino]‐3,5‐bis(2‐pyridyl)‐4H‐1,2,4‐triazole

The title compound, C₂₁H₁₉N₇, is a poly­pyridine ligand that is suitable for assembling complex metal systems capable of photoinduced electron transfer. The solid‐state structure has been determined at room temperature by single‐crystal X‐ray diffraction. The mol­ecule is not flat and both the bis­(pyridyl)­triazole and the benzyl­id­ene­amine fragments show significant distortions from planarity.     

Calorimetric evaluation of the interaction and absorption of eicosapentaenoic acid by biomembrane models

The interaction of eicosapentaenoic acid, a polyunsaturated fatty acid belonging to the omega-3 class, with biomembrane models represented by multilamellar or unilamellar vesicles made of dimyristoylphosphatidylcholine was monitored by means of differential scanning calorimetry technique. The calorimetric analysis of vesicle prepared in the presence of increasing molar fraction of eicosapentaenoic acid was carried out to show its maximum interaction with biomembrane models evaluating the effects of eicosapentaenoic acid on the biomembrane models thermotropic parameters (transition temperature and enthalpy variation). Furthermore, in order to detect the influence of the presence of hydrophilic or lipophilic media on the entity of the compound absorption by the biomembrane models, kinetic experiments were carried out.The results indicate that eicosapentaenoic acid strongly interacts with the biomembrane models depressing the transition temperature and the enthalpy variation. Eicosapentaenoic acid is absorbed by the biomembrane models and the absorption is affected by the used medium; in fact a bigger absorption happens in the presence of a lipophilic medium.     

Investigating halo substructures with annual modulation signature

Galaxy hierarchical formation theories, numerical simulations, the discovery of the Sagittarius Dwarf Elliptical Galaxy (SagDEG) in 1994 and more recent investigations suggest that the dark halo of the Milky Way can have a rich phenomenology containing non-thermalized substructures. In the present preliminary study, we investigate the case of the SagDEG (the best known satellite galaxy in the Milky Way crossing the solar neighborhood) analyzing the consequences of its dark matter stream contribution to the galactic halo on the basis of the DAMA/NaI annual modulation data. The present analysis is restricted to some WIMP candidates and to some of the astrophysical, nuclear and particle physics scenarios. Other candidates such as e.g. the light bosonic ones we discussed elsewhere, and other non-thermalized substructures are not yet addressed here. PACS 95.35.+d     

Chemical characterization of unconventional palm oils from Hyophorbe indica and two other endemic Arecaceae species from Reunion Island

Abstract

Chemical characteristics of novel seed oils, yet not investigated, from three endemic Arecaceae (palm) species from Reunion Island are described. Fatty acid profiles are performed using two-dimensional gas chromatography-mass spectrometry. Carotenoid contents are determined by high performance liquid chromatography-mass spectrometry. The results of the investigations emphasize the particular composition of the unconventional red seed oil from Hyophorbe indica. Characteristic features of this oil reveal a high degree of unsaturation (50% of polyunsaturated fatty acids, with a high content (17%) of omega-3), which is possibly a unique fatty acid composition in the Arecaceae family. The two other palm oils from Dictyosperma album and Latania lontaroides contain high level of saturated fatty acids very similar to that of the edible palm oil. H. indica oil is also very rich in valuable carotenoids; in particular, lutein, β-carotene and lycopene are detected in a high content (respectively 45, 23 and 35?mg.kg^?1 in oil).