Impact of the Spanish smoking law on exponsure to secondhand smoke in offices and hospitality venues: before-and-after study

BACKGROUND/OBJECTIVES: A smoking law was passed by the Spanish Parliament in December 2005 and was enforced by 1 January 2006. The law bans smoking in all indoor workplaces but only in some hospitality venues, because owners are allowed to establish a smoking zone (venues>100 m2) or to allow smoking without restrictions (venues<100 m2). The objective of the study is to assess the impact of the Spanish smoking law on exposure to secondhand smoke (SHS) in enclosed workplaces, including hospitality venues. MATERIALS AND METHODS: The study design is a before-and-after evaluation. We studied workplaces and hospitality venues from eight different regions of Spain. We took repeated samples of vapor-phase nicotine concentration in 398 premises, including private offices (162), public administration offices (90), university premises (43), bars and restaurants (79), and discotheques and pubs (24). RESULTS: In the follow-up period, SHS levels were markedly reduced in indoor offices. The median decrease in nicotine concentration ranged from 60.0% in public premises to 97.4% in private areas. Nicotine concentrations were also markedly reduced in bars and restaurants that became smoke-free (96.7%) and in the no-smoking zones of venues with separate spaces for smokers (88.9%). We found no significant changes in smoking zones or in premises allowing smoking, including discotheques and pubs. CONCLUSIONS: Overall, this study shows the positive impact of the law on reducing SHS in indoor workplaces. However, SHS was substantially reduced only in bars and restaurants that became smoke-free. Most hospitality workers continue to be exposed to very high levels of SHS. Therefore, a 100% smoke-free policy for all hospitality venues is required.

Thickening of phase change materials (PCM) to avoid segregation

Estudi elaborat a partir d’una estada a Çukurova University, Turquia, al juliol del 2006. L’emmagatzematge d’energia tèrmica ha atret interès en aplicacions tèrmiques com l’aigua calenta, la calefacció i l’aire condicionat. Aquests sistemes són útils per corregir la no coincidència entre la oferta i la demanda d’energia. Principalment hi ha dos tipus de sistemes d’emmagatzematge d’energia tèrmica, emmagatzematge amb calor sensible i amb calor latent. L’emmagatzematge amb calor latent és particularment atractiu degut a la seva habilitat de donar una densitat d’emmagatzematge d’energia més alt i la seva característica d’emmagatzemar calor a una temperatura constant corresponent a la temperatura de transició de fase de la substància emmagatzemadora de calor. Les salts hidratades orgàniques tenen certes avantatges com a materials d’emmagatzematge de calor latent sobre els materials orgànics. En canvi, quan les salts hidratades s’utilitzen com a materials de canvi de fase (PCM) apareixen alguns problemes en les aplicacions d’emmagatzematge de calor latent. Aquests són el subrefredament de les salts hidratades quan es congelen degut a les seves dèbils propietats de nucleació, i la separació de fase que hi apareix degut a una fusió incongruent. En aquest estudi, s’estabilitza sal de Glauber (Na2SO4.10H2O) amb diferents concentracions de poliacrilamida i gelatina per prevenir la fusió incongruent. Per prevenir el subrefredament s’utilitza un agent nucleant amb una estructura cristal•lina semblant a la de la sal de Glauber. La capacitat d’emmagatzematge de calor de les mostres de PCM estabilitzades amb diferents concentracions de gels polimèrics es determinen amb DCS i amb el mètode T-history.

Properties of nitrogen doped silicon films deposited by low-pressure chemical vapor deposition from silane and ammonia

Nitrogen doped silicon (NIDOS) films have been deposited by low-pressure chemical vapor deposition from silane SiH4 and ammonia NH3 at high temperature (750°C) and the influences of the NH3/SiH4 gas ratio on the films deposition rate, refractive index, stoichiometry, microstructure, electrical conductivity, and thermomechanical stress are studied. The chemical species derived from silylene SiH2 into the gaseous phase are shown to be responsible for the deposition of NIDOS and/or (silicon rich) silicon nitride. The competition between these two deposition phenomena leads finally to very high deposition rates (100 nm/min) for low NH3/SiH4 gas ratio (R¿0.1). Moreover, complex variations of NIDOS film properties are evidenced and related to the dual behavior of the nitrogen atom into silicon, either n-type substitutional impurity or insulative intersticial impurity, according to the Si¿N atomic bound. Finally, the use of NIDOS deposition for the realization of microelectromechanical systems is investigated.

Nanomechanical properties of molecular organic thin films

Using atomic force microscopy we have studied the nanomechanical response to nanoindentations of surfaces of highly oriented molecular organic thin films (thickness¿1000¿nm). The Young¿s modulus E can be estimated from the elastic deformation using Hertzian mechanics. For the quasi-one-dimensional metal tetrathiafulvalene tetracyanoquinodimethane E~20¿GPa and for the ¿ phase of the p-nitrophenyl nitronyl nitroxide radical E~2GPa. Above a few GPa, the surfaces deform plastically as evidenced by discrete discontinuities in the indentation curves associated to molecular layers being expelled by the penetrating tip.

High-Temperature magnetic ordering in a new organic magnet

Magnetization, heat capacity, and neutron diffraction experiments on the beta-phase of the dithiadiazolyl radical, p-NC.C6F4.CNSSN., provide conclusive evidence that this system exhibits noncollinear antiferromagnetism at 35.5 K, an unprecedented temperature for an organic radical. On the basis of magnetization and powder neutron diffraction results, coupled with theoretical calculations of the spin distribution within the molecule, a magnetic structure for this compound is proposed in which the interactions propagate through S . . .N contacts.

p-Nitrobenzyloxycarbonyl (pNZ) as Temporary Na-Protecting Group for Mild Solid-Phase Peptide Synthesis. Avoiding Diketopiperazine and Aspartimide Formation

p-Nitrobenzyloxycarbonyl was used as temporary protecting group for the -amino function in solid-phase peptide synthesis. The corresponding derivatives are solids, easy to be synthesized, and perform well in the solid-phase mode. pNZ is removed in practical neutral conditions in the presence of catalytic amounts of acid. They are orthogonal with the most common protecting groups used in peptide chemistry. They are specially useful in combination with Fmoc chemistry to overcome those side reactions associated with the used of the piperidine such DKP and aspartiimide formation. The flexibility of pNZ can be very useful for the preparation of libraries of small organic molecules.

A Headspace needle-trap method for the analysis of volatile organic compounds in whole blood

Needle trap devices (NTDs) are a relatively new and promising tool for headspace (HS) analysis. In this study, a dynamic HS sampling procedure is evaluated for the determination of volatile organic compounds (VOCs) in whole blood samples. A full factorial design was used to evaluate the influence of the number of cycles and incubation time and it is demonstrated that the controlling factor in the process is the number of cycles. A mathematical model can be used to determine the most appropriate number of cycles required to adsorb a prefixed amount of VOCs present in the HS phase whenever quantitative adsorption is reached in each cycle. Matrix effect is of great importance when complex biological samples, such as blood, are analyzed. The evaluation of the salting out effect showed a significant improvement in the volatilization of VOCs to the HS in this type of matrices. Moreover, a 1:4 (blood:water) dilution is required to obtain quantitative recoveries of the target analytes when external calibration is used. The method developed gives detection limits in the 0.020–0.080 μg L−1 range (0.1–0.4 μg L−1 range for undiluted blood samples) with appropriate repeatability values (RSD < 15% at high level and <23% at LOQ level). Figure of merits of the method can be improved by using a smaller phase ratio (i.e., an increase in the blood volume and a decrease in the HS volume), which lead to lower detection limits, better repeatability values and greater sensibility. Twenty-eight blood samples have been evaluated with the proposed method and the results agree with those indicated in other studies. Benzene was the only target compound that gave significant differences between blood levels detected in volunteer non-smokers and smokers