Pulsed laser deposition of organic and biological materials

We report on the deposition of soft matter thin films by Matrix Assisted Pulsed Laser Evaporation (MAPLE). In particular, thin layers of biological material (Bovine Serum Albumin) and polymers (polyfluorene) for medical and optoelectronic applications, were realized by laser irradiating a frozen solution containing a low amount of material diluted in a laser absorbing volatile solvent. The depositions were carried out varying different parameters as solvent–solute concentration, solvent nature, laser fluencies, etc. The optical, morphological, structural and spectroscopical properties were detected by means of different analyses as FTIR, photoluminescence, AFM and SDS.     

A model for atomic hydrogen–bimetal interactions

The adsorption of atomic H on the bimetallic FeNi(111) surface has been studied by ASED-MO tight binding calculations. The energy of the system was calculated by the atom superposition and electron delocalization molecular orbital (ASED-MO) method. Seven H locations on the alloy surface were selected and the hydrogen atom was positioned in their energy minima configurations.     

Persistent organic pollutants in farmed European sea bass (Dicentrarchus labrax,Linnaeus, 1758) from Sicily (Italy)

Farmed European sea bass (Dicentrarchus labrax, Linnaeus, 1758) were collected during 2016 from one Sicilian fish farm that uses two different rearing systems – sea cage and concrete tank – for determination of polychlorinated biphenyls (PCB), organochlorine pesticides (OCP) and polycyclic aromatic hydrocarbons (PAH) residues by HRGC-MS/MS. Moreover, commercial feed was analysed. This study aimed to determine whether the different rearing systems affect the concentration of these compounds, and to assess the safety of cultured fish. PCBs represent the pollutants with the highest concentration; in particular, PCB138 and 153 have the highest concentration in almost all samples. Among OCPs, only 4,4′-DDE, 4,4′-DDD and 4,4′-DDT residues have been detected. Concerning PAHs, only fluorene and phenanthrene were detected, in both rearing systems. Although some residues of organic pollutants were found in the analysed samples, they were always below the MRLs, so the results suggest that farmed sea bass are safe for human consumption.     

Synthesis, Molecular Characterization and Preliminary Antioxidant Activity Evaluation of Quercetin Fatty Esters

Quercetin shows interesting pharmacological effects, but its use in topical applications is limited by its low skin permeability and solubility. In this work, the synthesis of highly lipophilic quercetin esters with oleic, linoleic and linolenic acid useful as topical quercetin prodrugs is reported. Partial OH esterification is advisable to maintain the antioxidant activity of these compounds; tetraesters and triesters can be achieved by modulating the reaction conditions utilized for the total esterification of quercetin. The chemical structures of the esters were proven by spectroscopic techniques; quantum chemical NMR calculation were mandatory to unequivocally assign the free position in triesters. Finally, the antioxidant activity of all the synthesized compounds was determined by the 2,2-diphenyl-1-picryl-hydrazyl method and by 2,2-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid) assay.     

Synthesis of Indole Derivatives from 2-Alkynylanilines by Means of Gold Catalysis

The peculiar features of gold(III) and gold(I) species include exceptional carbophilicity and, at the same time, lone pair affinity. Such a combination offers many advantages for the development of more sustainable approaches to the synthesis of indole derivatives from readily available 2-alkynylanilines. This mini-review critically summarizes the literature reports in this field, with the aim to encourage further research activities in this promising area.     

Co and Ni supported on CeO2 as selective bimetallic catalyst for dry reforming of methane

Co/CeO₂ (Co 7.5 wt.%), Ni/CeO₂ (Ni 7.5 wt.%) and Co–Ni/CeO₂ (Co 3.75 wt.%, Ni 3.75 wt.%) catalysts were prepared by surfactant assisted co-precipitation method. Samples were characterized by X-Ray diffraction, BET surface areas measurements, temperature programmed reduction and tested for the dry reforming of methane CH₄ + CO₂ → 2CO + 2H₂ in the temperature range 600–800 °C with a CH₄:CO₂:Ar 20:20:60 vol.% feed mixture and a total flow rate of 50 cm³ min⁻¹ (GHSW = 30,000 mL g⁻¹ h⁻¹). The bimetallic Co–Ni/CeO₂ catalyst showed higher CH₄ conversion in comparison with monometallic systems in the whole temperature range, being 50% at 600 °C and 97% at 800 °C. H₂/CO selectivity decreased in the following order: Co–Ni/CeO₂ > Ni/CeO₂ > Co/CeO₂. Carbon deposition on spent catalysts was analyzed by thermal analysis (TG-DTA). After 20 h under stream at 750 °C, cobalt-containing catalysts, Co/CeO₂ and Co–Ni/CeO₂, showed a stable operation in presence of a deposited amorphous carbon of 6 wt.%, whereas Ni/CeO₂ showed an 8% decrease of catalytic activity due to a massive presence of amorphous and graphitic carbon (25 wt.%).     

Growth/no growth interfaces of Bacillus cereus, Staphylococcus aureus and Salmonella enteritidis in model systems based on water activity, pH, temperature and ethanol concentration

This study focuses its attention on the boundary between the growth and no growth of three strains ofSalmonella enteritidis , Bacillus cereus and Staphylococcus aureus in the presence of growth controlling factors such as temperature, pH, water activity (A_w) and ethanol concentration. Preliminarly, the minimal values of pH, A_wand temperature, and the maximum ethanol concentrations allowing the growth of the considered micro-organisms were determined. The calculation of these values enabled the use of logistic model to evaluate the growth/no growth boundary for the bacteria in relation to the considered independent variables. The location of the growth/no-growth boundaries for S. enteritidis and Staph. aureus were strongly affected, at the same ethanol concentration, by temperature, pH and A_w. Among the considered species, Staph. aureus was endowed with the highest sensitivity to low pH values whileB. cereus's growth/no growth interface, was quite unaffected by the combination of the stresses, when the physico–chemical conditions were above the minimum for growth. The effects of temperature, A_wand ethanol on the limitation of growth of the considered species were not merely additive. It was possible to identify the combinations of such factors preventing the growth of Salmonella enteritidis, Staph. aureus and B. cereus.     

Survival Skills for The is Professional

IS professionals can only dream of the days when technical brilliance alone was enough to ensure a successful career. Now business acumen and a strong understanding of customer expectations are vital to long-term career survival. Based on their study of 75 experienced IS professionals, the authors present guidelines for fostering the development of customer-oriented IS professionals.     

Intranucleolar localization of DNA topoisomerase IIalpha is a distinctive feature of necrotic, but not of apoptotic, Jurkat T-cells

Two distinct types of cell death have been described: apoptosis and necrosis. However, it is becoming increasingly clear that the differences between these two types are far less numerous than initially thought. Morphological analyses might provide important information to distinguish apoptotic from necrotic samples. We recently reported that in necrotic, but not apoptotic, HL-60 human myeloid leukaemia cells, the nuclear protein topoisomerase IIalpha concentrated in nucleoli. In order to ascertain whether or not this phenomenon was restricted to a peculiar cell type or could be detected also in cells of lymphoid lineage, we performed an investigation aimed at defining the localization of topoisomerase IIalpha in apoptotic and necrotic Jurkat human T lymphoblastoid cells. Immunofluorescence staining demonstrated that topoisomerase IIalpha was excluded from the condensed chromatin of apoptotic cells, whereas in necrotic cells it was localized in discrete nuclear dots. Immuno-electron microscopy analysis showed that topoisomerase IIalpha was undetectable in nucleoli of normal and apoptotic cells, whereas it was present in the nucleolus of necrotic cells irrespectively of the type of inducer used (ethanol, H(2)O(2), HgCl(2)). Taken together, our findings identify topoisomerase IIalpha as a potential morphological marker useful to discriminate between apoptotic and necrotic cells.