Sun Protection Habits and Sun Exposure of Physical Education Teachers in the South of Spain

The high prevalence and increasing incidence of skin cancer (SC) is a significant public health problem. We can address its main risk factor, which is incident and accumulated solar radiation, and its damages by disseminating knowledge and promoting changes in habits and attitudes toward the sun. The influence of teachers in the education of young people is crucial. Physical education teachers (PET) spend the majority of their time outdoors, thereby exposing themselves to solar radiation daily and greatly increasing the risk of SC. We carried out a case–control study matching for age and gender through surveys about photoexposure and photoprotection habits on a sample of 200 teachers (100 PET and 100 non‐PET) on South of Spain. The results confirmed that there is a significant difference in sun exposure during the workday; PET group showed higher exposure (P < 0.01). We ascertained that photoprotection habits are deficient across the population. These data contribute to the understanding of the danger associated with poor sun protection among teachers (primary and secondary school teachers) and its mitigation. It is also worth noting that future prevention campaigns will be necessary for the subsequent correct transmission of the habits to students.     

Hybrid Materials from Carbon Nanotubes,Nickel Tetrasulfonated Phthalocyanine and Thin Polymer Layers for the Selective Electrochemical Activation of Nitric Oxide in Solution

The elaboration of hybrid materials from single‐wall carbon nanotubes (SWCNT) and tetrasulfonated nickel phthalocyanine (NiTSPc) was electrochemically performed to obtain chemically modified electrodes with improved electrocatalytic activity towards the electrooxidation of nitric oxide (NO). The characterization of these hybrid electrodes was achieved by cyclic voltammetry and AFM. The electrochemical performances of the electrodes towards the oxidation of NO were then analyzed by chronoamperometry and the obtained results show that the presence of SWCNT greatly enhances the electrocatalytic performances in terms of current intensity. Additional coatings were then electrodeposited over the hybrid electrodes to act as selective membranes against four major interfering analytes: nitrite, ascorbate, hydrogen peroxide and L ‐arginine. Several polymer coatings were tested to achieve the best balance between sensitivity to NO and selectivity against interferents.     

Equilibrium height of a liquid in a gap between corrugated walls under spontaneous capillary penetration

A simple and general method is presented to calculate the equilibrium surface of a liquid that penetrates spontaneously, due to capillarity, in the gap between two vertical corrugated plates. Several properties of the equilibrium solution are discussed and the results are backed by a qualitative experiment.     

Proton NMR spectra and structure of chlorotin(IV) ternary complexes of 8-quinolinol and its 5,7 dichloro and 2 methyl-5,7 dichloro derivatives

The low temperature ¹H NMR spectra in d-chloroform of the ternary complexes bis-(8-quinolinato) tin(IV) dichloride, bis-(5,7 dichloro-8-quinolinato) tin(IV) dichloride, and bis-(2 methyl-5,7-dichloro-8-quinolinato) tin(IV) dichloride have been obtained. The spectra showed that for the three complexes, only two configurations were appreciably populated, their free energy differences being equal to 0.28, 0.08 and ?0.04 kcal/mol respectively. The proton chemical shifts, the ¹H-¹H coupling constants and some of the ¹H-¹¹⁹Sn coupling constants have been obtained for each complex in the two configurations. An approximate computation of chemical shifts, including aromatic ring magnetic anisotropies and electric effects from polar groups, allowed the identification of the two configurations as the cis-cis-trans and the cis-trans-cis (with respect to Cl, N and O atoms), the former being the more populated one.     

PHOTOSENSITIZATION OF MCF-7 CELLS WITH DIAZIQUONE USING VISIBLE LIGHT: CORRELATION WITH DNA STRAND BREAKS AND FREE RADICAL PRODUCTION

The ability of visible light to enhance the activity of diaziquone (AZQ) was evaluated in MCF-7 human breast cancer cells. MCF-7 cells were sensitive to AZQ, while visible light illumination had no appreciable effect on cell survival. In the presence of AZQ, visible light potentiated AZQ's cytotoxicity. This potentiation of AZQ activity correlated with a 2-2.5-fold increase in the formation of free radicals (hydroxyl radicals and AZQ semiquinone) and with the production of DNA strand breaks as measured by electron paramagnetic resonance and gel electrophoresis respectively. These results support the hypothesis that free radical formation is part of the mechanism of action of AZQ.     

Sterols isolated from Tubifex tubifex

Four 3beta-hydroxysterols isolated from chloroform extract from Tubifex tubifex were shown to have the structures stigmast-23-en-3-ol, stigmast-7,14-dien-3-ol, 22-dehydrocholesterol, and 24 methylenecholesterol based on spectroscopic methods. Stigmasterol and beta-sitosterol were also investigated on the basis of mass spectral analyses and compared with known compounds.     

Metathesis of carbonyl containing olefins by 2nd generation Ru alkylidene catalysts: A computational study

The metathesis reaction of cis-1,4-diacetoxy-2-butene (2) mediated by a second generation ruthenium alkylidene catalyst (IMesH₂)Cl₂RuCHPh (1) where IMesH₂ is 1,3-dimesityl-4,5-dihydroimidazol-2-ylidene group has been modeled at PBE0/LACV3P*//PBE0/LACVP* level of theory. The calculations demonstrate that the driving force of the metathesis reaction is the formation of a Ru–O coordination bond in the corresponding Ru acetoxyethylidene complex 8a-II. The free activation energy of metathesis by 8a-II complex is higher than that of the metathesis reaction mediated by the conventional ruthenium alkylidene catalyst (8b), due to the additional stabilization of the Ru center by a carbonyl oxygen revealing lower reactivity of carbonyl containing ruthenium carbene species. It has been shown that conjugation between carbonyl and olefin double bonds decreases the reactivity of olefins due stabilization of nonproductive complex between Ru center and carbonyl group of the olefin.