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71.
Valente P Forastiere F Bacosi A Cattani G Di Carlo S Ferri M Figà-Talamanca I Marconi A Paoletti L Perucci C Zuccaro P 《Tobacco control》2007,16(5):312-317
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 establishmentsResults
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72.
Simonetta Fois Manuela Sanna Giuseppe Stara Tonina Roggio Pasquale Catzeddu 《European Food Research and Technology》2011,232(4):713-722
Four commercial semolinas and four low-grade semolinas (LGS) samples were used in this study to make flat crispy bread (Carasau).
The meals, doughs, and bread were compared with respect to a set of physical, chemical, and textural characteristics, and
the bread evaluated by a trained sensory panel. LGSs had a higher extraction rate (higher ash content), finer granularity,
and a higher damaged starch content than semolinas. The study revealed the key role of dry gluten content in determining hydration
capacity of the dough, whereas damaged starch affected water absorption only in semolina samples. Gluten index and the ratio
of gluten tenacity to extensibility (alveograph P/L) were significantly correlated with the weight of the dough discs following sheeting and molding. The panelists gave the
highest quality score to the bread with the highest values of crackling and hardness. Textural and sensory attributes were
both correlated with one another, and with gluten strength and tenacity, but not with the gluten content of the meal, which
only affected final moisture content of the bread. Meal samples with a more tenacious and elastic gluten were more suited
to produce flat crispy breads. The yellowness of durum wheat bread could not be predicted by measuring the color of the meal
with a reflectance method. 相似文献
73.
The growth and survival of Aeromonas hydrophila in three types of natural mineral waters were investigated. Mineral waters with different levels of mineral content (low, medium, and high) were experimentally contaminated with A. hydrophila, stored at different temperatures (10 degrees C and 20 degrees C), and analyzed at intervals over a 60-day period. Water samples that were not experimentally contaminated were investigated for indigenous A. hydrophila. The results confirmed that A. hydrophila may occur naturally in mineral waters and showed that the level of mineral content, temperature, length of storage, and, in some cases, the type of container used may favor the growth of A. hydrophila. The greatest proliferation was observed in water with a low mineral content stored in PET bottles at 10 degrees C, in which A. hydrophila peaked at day 28 (4.47 +/- 0.01 log CFU/100 ml). At 20 degrees C, the same load was observed at day 60. The presence of high densities of A. hydrophila in bottled mineral water can constitute a risk for some groups of consumers, such as elderly and immunocompromised persons. 相似文献
74.
Giovanni Semeraro Verner Andersen Hans H. K. Andersen Marco de Gemmis Pasquale Lops 《Universal Access in the Information Society》2008,7(3):179-194
The main contribution of this work is the design of an application framework based on both conversational agents and user
profiling technologies for the development of e-commerce services. User profiles are exploited by conversational agents to
help customers in retrieving potentially interesting products from a catalogue. Three techniques were used for collecting
data for a usability test: eye-movement tracking, questionnaire, and recording the user-system dialogue. The main outcomes
of the experimental sessions are: (1) the dialogue capabilities of the agent facilitate the interaction between the user and
the e-commerce site; and, (2) user profiles improve the retrieval capabilities of the agent. Finally, some limitations of
the user profiling techniques adopted in the framework are discussed and a more sophisticated content-based profiling technique
is proposed. 相似文献
75.
The AidB protein is involved in the adaptive response to DNA alkylation damages in Escherichia coli. Functional proteomic experiments were designed to elucidate AidB biological functions in the presence and in the absence of methyl methanesulfonate as methylating agent. Several proteins were identified in both conditions and according to their reported biological activities, the inter-actors were grouped into three different functional categories: stress response, energetic metabolic pathways and nucleic acid metabolism. Particularly, the interaction between AidB and UvrA, a member of the UvrABCD nucleotide excision system, suggested a new interesting putative role for AidB. 相似文献
76.
Xiaoyan Xia Philip K. Hopke Bernard S. Crimmins James J. Pagano Michael S. Milligan Thomas M. Holsen 《Journal of Great Lakes research》2012
As part of the U.S. Great Lakes Fish Monitoring and Surveillance Program (GLFMSP), more than 300 lake trout (Salvelinus namaycush) and walleye (Stizostedion vitreum vitreum) collected from the Laurentian Great Lakes each year from 2004 to 2009, have been analyzed for total toxaphene and eight selected congeners. The analytical results show fish toxaphene concentrations are quite different among lakes. Between 2004 and 2009, Lake Superior lake trout had the highest concentration (119 to 482 ng/g) and Lake Erie walleye had the lowest concentration (18 to 47 ng/g). Combining these results with the historical total toxaphene data (1977–2003), temporal changes were examined for each lake. Because of different analytical methods used in the previous studies, the historical data were adjusted using a factor of 0.56 based on a previous inter-method comparison in our laboratory. Trend analysis using an exponential decay regression showed that toxaphene in Great Lakes fish exhibited a significant decrease in all of the lakes with t1/2 (confidence interval) of 0.9 (0.8–1.1) years for Lake Erie walleye, 3.8 (3.5–4.1) years for Lake Huron lake trout, 5.6 (5.1–6.1) years for Lake Michigan lake trout, 7.5 (6.7–8.4) years for Lake Ontario lake trout and 10.1 (8.2–13.2) years for Lake Superior lake trout. Parlars 26, 50 and 62 were the dominant toxaphene congeners accounting for 0.53% to 41.7% of the total toxaphene concentration. Concentrations of these congeners generally also decreased over time. 相似文献
77.
A measurement technique based on Electrical Impedance Spectroscopy (EIS) aimed at discriminating electrical effects of the electrical treatment from the electrical characteristics of drug delivery in human skin is presented. The technique turns out to be useful as the first and most crucial step in determining the drug delivered into the skin after electrical treatment. After recalling the background of electrical measurements principle and electrical modeling of biological tissues, the proposed measurement procedure is illustrated. Then, experimental tests of in vivo characterization of the procedure are reported, and the obtained results are discussed. 相似文献
78.
Francesco Basile Fabrizio Caccavale Pasquale Chiacchio Jolanda Coppola Alessandro Marino 《Mechatronics》2013,23(8):1100-1112
In this paper a two-layer decentralized framework for kinematic control of cooperative and collaborative multi-robot systems is developed. The motion of the system is specified at the workpiece level, by adopting a task-oriented formulation for cooperative tasks. The first layer computes the motion of the single arms in the system. In detail, the control unit of each robot computes the end-effector motion references in a decentralized fashion on the basis of the knowledge of the assigned cooperative task and the motion references computed by its neighbors. Then, in the second layer, each control unit computes the reference joint motion of the corresponding manipulator from the end-effector reference motion. The approach is, then, tested in simulation on a work-cell composed by several manipulators, and experimentally on a dual-arm kinematically redundant work-cell composed by industrial manipulators. 相似文献
79.
Buccafurri Francesco De Meo Pasquale Lax Gianluca Ursino Domenico Fugini Mariagrazia Modafferi Stefano Pernici Barbara Furnari Roberto Goy Anna Lops Pasquale Redavid Domenico Semeraro Giovanni 《Multimedia, IEEE》2009,16(1):26-35
An integrated approach to quality of service for content delivery using Web services includes quality definitions, user contracts, and fault monitoring. 相似文献
80.
This paper presents a method to compute the influence exerted by reinforced-concrete beams built on top of free or anchored, embedded retaining structures. A beam scheme and a two-dimensional wall scheme are solved iteratively until satisfying the compatibility conditions of horizontal displacement and rotation. The importance of accounting for top-beam effects is shown through a case study, which is also analyzed by the developed method. 相似文献