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101.

Background

A smoking ban in all indoor public places was enforced in Italy on 10 January 2005.

Methods

We compared indoor air quality before and after the smoking ban by monitoring the indoor concentrations of fine (<2.5 μm diameter, PM2.5) and ultrafine particulate matter (<0.1 μm diameter, UFP). PM2.5 and ultrafine particles were measured in 40 public places (14 bars, six fast food restaurants, eight restaurants, six game rooms, six pubs) in Rome, before and after the introduction of the law banning smoking (after 3 and 12 months). Measurements were taken using real time particle monitors (DustTRAK Mod. 8520 TSI; Ultra‐fine Particles Counter‐TRAK Model 8525 TSI). The PM2.5 data were scaled using a correction equation derived from a comparison with the reference method (gravimetric measurement). The study was completed by measuring urinary cotinine, and pre‐law and post‐law enforcement among non‐smoking employees at these establishments

Results

In the post‐law period, PM2.5 decreased significantly from a mean concentration of 119.3 μg/m3 to 38.2 μg/m3 after 3 months (p<0.005), and then to 43.3 μg/m3 a year later (p<0.01). The UFP concentrations also decreased significantly from 76 956 particles/cm3 to 38 079 particles/cm3 (p<0.0001) and then to 51 692 particles/cm3 (p<0.01). Similarly, the concentration of urinary cotinine among non‐smoking workers decreased from 17.8 ng/ml to 5.5 ng/ml (p<0.0001) and then to 3.7 ng/ml (p<0.0001).

Conclusion

The application of the smoking ban led to a considerable reduction in the exposure to indoor fine and ultrafine particles in hospitality venues, confirmed by a contemporaneous reduction of urinary cotinine.  相似文献   
102.
Electron device degradation, although not directly accounted for, represents a key issue in microwave circuit design. This is especially true when the particular applications involved (e.g., satellite, military, consumer) do not allow or strongly discourage any kind of maintenance. As a matter of fact, in order to account for device degradation in circuit design, a suitable electron device model is needed which is able to predict the performance degradation as a function of the actual electrical regime involved in the device operation. Such a kind of model is not available in literature. In this paper, quantitative results are provided for device degradation indicators which correlate DC and RF stress experiments. These results can be considered an important step toward the definition of a nonlinear model accounting for device degradation.  相似文献   
103.
Chicks learned to find food hidden under sawdust by ground-scratching in the central position of the floor of a closed arena. When tested in an arena of identical shape but a larger area, chicks searched at 2 different locations, one corresponding to the correct distance (i.e., center) in the smaller (training) arena and the other to the actual center of the test arena. When tested in an arena of the same shape but a smaller area, chicks searched in the center of it. These results suggest that chicks are able to encode information on the absolute and relative distance of the food from the walls of the arena. After training in the presence of a landmark located at the center of the arena, animals searched at the center even after the removal of the landmark. Marked changes in the height of the walls of the arena produced some displacement in searching behavior, suggesting that chicks used the angular size of the walls to estimate distances. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
104.
A continuous gelation process for producing aluminum and zirconium hydroxide microparticles was conceived and tested in a lab‐scale apparatus. Fluidized state was devised as an appropriate hydrodynamic configuration to maintain the reacting sol microdrops suspended: stable non‐coalescing spherical gel particles in a size range quite below 100 μm were produced via gelation. The microspheres produced by a subsequent calcination step showed a diameter ranging between 2 μm and 20 μm. This powder, without further size classification, was an optimal product to manufacture test specimens by sintering. Measurements on the mechanical properties, such as toughness, flexural strength and hardness, classified the test bars as a very promising ceramic material. In order to enlighten the chemical drying phenomenon and devise the main governing mechanisms acting in the gelation reaction, an extremely simplified experimental system was set. A single drop of sol was deposited into a given amount of the dehydrating liquid medium and observed by an optical microscope; image analysis permitted us to identify the gel formation, the size reduction kinetics, as well as secondary phenomena.  相似文献   
105.
The reliability of RF MEMS switches is typically reduced by charging effects occurring in the dielectrics. The aim of this paper is to discuss these effects, and to propose analytical and equivalent circuit models which account for most of the physical contributions present in the structure.  相似文献   
106.
Many community- and hospital-based group treatment programs have an open enrolment, that is, a rolling admissions structure, in which a group member who drops out or successfully completes therapy is replaced by another individual. Although practically efficient and perhaps clinically useful, the interdependence of these group participants' data may result in incorrect inferences drawn from the data analyses if this interdependence is not accounted for. We present an analytic strategy that uses time varying covariates in multilevel models to illustrate a methodology to address these data analysis problems. Participants were adults with eating disorders (N = 229) who attended an average of 12 weeks of a rolling admissions group-based day hospital program during an 8-year period, and who completed a group therapy alliance measure weekly. Individual alliance to the group increased from week to week, and this growth remained significant even after controlling for the time varying level of other group members' alliance to the group. Further, the level of an individual's alliance score during any given week was positively related to the group's alliance during that week. The multilevel time varying covariate models presented here add to a very small but emerging set of analytic strategies available for researchers to address some of the hurdles to correctly analyze data from rolling admissions group-based treatment programs. Results from this study provide evidence that a group's culture is passed on and affects an individual's alliance to the group despite changes in group membership. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
107.
In this paper, we review the research literature on attachment and eating disorders and suggest a framework for assessing and treating attachment functioning in patients with an eating disorder. Treatment outcomes for individuals with eating disorders tend to be moderate. Those with attachment-associated insecurities are likely to be the least to benefit from current symptom-focused therapies. We describe the common attachment categories (secure, avoidant, anxious), and then describe domains of attachment functioning within each category: affect regulation, interpersonal style, coherence of mind, and reflective functioning. We also note the impact of disorganized mental states related to loss or trauma. Assessing these domains of attachment functioning can guide focused interventions in the psychotherapy of eating disorders. Case examples are presented to illustrate assessment, case formulation, and group psychotherapy of eating disorders that are informed by attachment theory. Tailoring treatments to improve attachment functioning for patients with an eating disorder will likely result in better outcomes for those suffering from these particularly burdensome disorders. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
108.
In the last years many studies have been carried out on the possible improvements of the in situ thermal conductance measurement; as well known, this has to be derived by recorded values of temperatures and heat fluxes. A big effort has been addressed in the implementation and comparison of different analysis methods. The aim of this paper is to widen the existent literature in the study of the influence of different kinds of input data on the final result. First the problem of analysing input data with significant drift in temperature is considered, adopting both nominal clean and noise affected data. Then the effect due to the presence of the Heat Flux Meter (HFM) on the thermal field of the testing element has been analysed, as well as the possibility of recording HFM surface temperature. These studies are based on Finite Element Method (FEM) simulations; both nominal clean and noise affected data have been considered as input. Finally, a difference in emissivity between the heat flux meter and internal plaster surface has been analysed by means of FEM simulations based on nominal clean data. An overall estimation of the occurred deviations in the different cases is shown.  相似文献   
109.
The need of label declaration for egg proteins is temporarily suspended when they are used as a processing aid in winemaking, because of a lack of scientific data concerning their actual permanence as residual proteins in fined wines.The possibility to detect residual egg proteins in red wines treated with a commercial egg white preparation was studied. By using an immunochemical method residual egg proteins were detected in the experimental red wines only for doses of fining agent of 50 g/hL or higher, whereas no residual proteins were detected by this system in a commercial red wine.A simple method based on the recovery and identification of the wine fining proteins by liquid chromatography coupled with tandem MS (LC-MS/MS) in a gel-free approach was developed. This allowed the detection of egg proteins in red wines fined down to 5 g/hL of commercial egg white preparation and also in the commercial red wine. These results indicate that the analytical approach here suggested is superior to the immunochemical methods in detecting egg proteins in wines. Therefore hypersensitivity reactions after consumption of wines treated with egg proteins can be a real risk for egg-allergic people.  相似文献   
110.
In this article, we propose an agent‐based approach for managing e‐commerce activities. In our approach, an agent is present in each e‐commerce site, managing the information stored there. In addition, another agent is associated with each customer, handling his/her profile. The proposed approach is based on the use of a particular conceptual model called the Behaviour‐Semantic Distance and Relevance (B‐SDR) network, which is capable of uniformly representing and handling information stored in e‐commerce sites and customer profiles. The capabilities of the B‐SDR network model are exploited to let customer and site agents cooperate in such a way in order to support a customer in identifying, whenever he/she accesses an e‐commerce site, those products and services present in the site itself and for better matching his/her interests. The approach has been implemented in a prototype in which its functionalities are discussed here also. © 2004 Wiley Periodicals, Inc.  相似文献   
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