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231.
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232.
Bove CG De Dea Lindner J Lazzi C Gatti M Neviani E 《International journal of food microbiology》2011,144(3):569-572
Parmigiano Reggiano (PR) is an Italian cooked, long-ripened cheese made with unheated cow's milk and natural whey starter. The microflora is involved in the manufacturing of this cheese, arising from the natural whey starter, the raw milk and the environment. Molecular studies have shown that mesophilic non-starter lactic acid bacteria (NSLAB) are the dominant microflora present during the ripening of PR. In this study, a characterisation of Lactobacillus rhamnosus isolated from a single PR manufacturing and ripening process is reported, using a combination of genotypic fingerprinting techniques (RAPD-PCR and REP-PCR). The intraspecies heterogeneity evidenced for 66 strains is correlated to their abilities to adapt to specific environmental and technological conditions. The detection of biotypes that correlate with specific moments in cheese ripening or differential development throughout this process suggests that these strains may have specific roles closely linked to their peculiar technological properties. 相似文献
233.
234.
Lombardi A Maistro LD De Dea P Gatti M Giraffa G Neviani E 《The Journal of dairy research》2002,69(1):139-149
In the present work, 67 strains of Lactobacillus helveticus isolated from whey starter cultures and cheeses were identified and grouped by genotypic and phenotypic methods. Strains were identified by sugar fermentation pattern, by cell-wall protein profile, and by probe hybridisation. Phenotypic diversity was evaluated by a chemometric model taking into account biochemical characteristics (i.e. acidifying and peptidase activities) of technological interest. Genotypic diversity was evidenced by RAPD-PCR, which provided stran-specific patterns and revealed the occurrence of different strains. The RAPD-PCR profiles were clustered according to their similarities: the groups obtained, together with the cell-wall protein profiling and the chemometric information, could be sometimes correlated with the type of cheese and/or dairy niches used as sources of strains. A computerised analysis of genotypic and phenotypic information could be successfully applied for rapid and reliable differentiation and characterisation of Lb. helveticus isolates occurring in different dairy products. 相似文献
235.
Laura Cavallarin Sara Antoniazzi Ernesto Tabacco Giorgio Borreani 《Journal of the science of food and agriculture》2006,86(9):1383-1390
The aim of the study was to investigate the effects of stage of maturity, wilting and inoculant application on proteolysis in field pea herbage and silage in northern Italy. Semi‐leafless field peas were harvested at four progressive morphological stages (end of flowering, I; beginning of pod filling, II; advanced pod filling, III; beginning of ripening, IV). For each stage of growth, the herbage was field wilted to a dry matter (DM) content around 330 g kg?1. The unwilted and wilted herbages were ensiled with (I) and without (C) a lactic acid bacteria (LAB) inoculant. The stage of growth significantly affected all the nitrogen fraction concentrations both in herbage and in silage. Extensive proteolysis took place in silages made at early morphological stages and characterised by a high crude protein content (around 240 g kg?1 DM), as shown by the non‐protein nitrogen (NPN) value (around 700 g kg?1 total N or higher). Neither inoculum nor wilting helped to reduce the protein degradation in these silages. The level of proteolysis was reduced in silages made from the pod filling stage onwards where most of the protein was localised in the seed and a better fermentation pattern was observed. The amino acid (AA) composition of silages made at stage IV was close to that of fresh herbage, with minimal losses of nutritionally essential amino acids for ruminants. Copyright © 2006 Society of Chemical Industry 相似文献
236.
Giorgio Gianquinto Marco Fecondini Mirco Mezzetti Francesco Orsini 《Journal of the science of food and agriculture》2010,90(3):482-493
BACKGROUND: Farming is considered one of the main causes of land degradation and underground water pollution. The increased availability of agricultural inputs has led to a dramatic rise in yields, which has resulted in soil fertility spoilage and overuse of fertilisers. Therefore horticultural practice improvement must consider appropriate nitrogen (N) management. This paper reports results on the application of an optical diagnostic system (N‐tester) to guide N fertilisation in muskmelon (Cucumis melo L.) over a 3 year trial. Results on fresh and postharvest quality are also presented. RESULTS: Fertilisation events mirrored increases in N‐tester values during the season, and a significant linear relationship (R2 = 0.628) was observed between N‐tester readings and leaf chlorophyll content. The N‐tester‐guided fertilisation treatments were characterised by yields comparable to the control, but with significantly lower applications of N (down to 17–66% of the N distributed in the control). Moreover, the N‐tester treatments yielded fruits with higher sugar content. This was also true after storage, when N‐tester fruits also showed reduced weight loss associated with lower transpiration and ethylene emission rates. CONCLUSION: Through the use of ‘spy plots’ kept at optimal nutritional status and the adoption of a threshold for N application throughout the growing cycle of muskmelon, the N supply was significantly reduced. Therefore a correct application of N‐tester allowed the plant N requirement to be reduced and the fruit sugar content and storability to be increased without adversely affecting the yield. Copyright © 2009 Society of Chemical Industry 相似文献
237.
ABSTRACT: The use of pulsed high hydrostatic pressure was investigated as a possible approach to stabilize foodstuffs. The objective of this article was to investigate the effect of the main processing variables (pressure [150 to 300 MPa], temperature levels [25 to 50 °C], and pulse number [1 to 10]) on the sanitation of nonpasteurized clear Annurca apple juice as well as freshly-squeezed clear orange juice. The aim of the article was the optimization of the process parameters in step-wise pressure treatment (pressure holding time of each pulse: 60 s, compression rate: 10.5 MPa/s, decompression time: 2 to 5s). The shelf life of the samples, processed at optimized conditions, was evaluated in terms of microbiological stability and quality retention. According to our experimental results, the efficiency of pulsed high pressure processes depends on the combination of pulse holding time and number of pulses. The pulsed high pressure cycles have no additive or synergetic effect on microbial count. The efficacy of the single pulses decreases with the increase of the pulse number and pressure level. Therefore the first pulse cycle is more effective than the following ones. By coupling moderate heating to high pressure, the lethality of the process increases but thermal degradation of the products can be detected. The optimization of the process condition thus results in a compromise between the reduction of the pressure value, due to the synergetic temperature action, and the achievement of quality of the final production. The juices processed under optimal processing conditions show a minimum shelf life of 21 d at a storage temperature of 4 °C. 相似文献
238.
Giacomo Luigi Petretto Carlo Ignazio Giovanni Tuberoso Maurizio Antonio Fenu Jonathan P. Rourke Omar Belhaj Giorgio Pintore 《International Journal of Food Properties》2017,20(9):2016-2027
The bioprospecting of several monofloral Moroccan honeys was carried out. The antiradical activity expressed as mmol Trolox equivalents/kg of honey and evaluated by 2,2-diphenyl-1-picrylhydrazyl assay, ranged from 0.15 for euphorb honey to 1.08 for citrus honey. The antioxidant activity expressed as mmol Fe2+/kg and evaluated by ferric ion reducing antioxidant power assay, ranged from 0.96 for euphorb honey to 4.74 for orange honey. The total phenol content was evaluated by colorimetric assay, while the color attributes were evaluated as transmittance data. Significant Pearson correlation factors were found between total polyphenol amount and antioxidant activity and between color attributes and antioxidant activity. Furthermore the chemical composition of volatile organic compounds was determined. The volatile organic compounds chemical composition of the studied honeys was mainly represented by terpene and benzene derivatives, Maillard reaction products, isoprenoids, and hydrocarbons. The volatiles fingerprint, as well as a targeted high-performance liquid chromatography analysis of the polar components, was used to tentatively confirm the declared botanical origin of the samples studied. 相似文献
239.
Farfaletti A Astorga C Martini G Manfredi U Mueller A Rey M De Santi G Krasenbrink A Larsen BR 《Environmental science & technology》2005,39(17):6792-6799
One of the major technological challenges for the transport sector is to cut emissions of particulate matter (PM) and nitrogen oxides (NOx) simultaneously from diesel vehicles to meet future emission standards and to reduce their contribution to the pollution of ambient air. Installation of particle filters in all existing diesel vehicles (for new vehicles, the feasibility is proven) is an efficient but expensive and complicated solution; thus other short-term alternatives have been proposed. It is well known that water/diesel (W/ D) emulsions with up to 20% water can reduce PM and NOx emissions in heavy-duty (HD) engines. The amount of water that can be used in emulsions for the technically more susceptible light-duty (LD) vehicles is much lower, due to risks of impairing engine performance and durability. The present study investigates the potential emission reductions of an experimental 6% W/D emulsion with EURO-3 LD diesel vehicles in comparison to a commercial 12% W/D emulsion with a EURO-3 HD engine and to a Cerium-based combustion improver additive. For PM, the emulsions reduced the emissions with -32% for LD vehicles (mass/km) and -59% for the HD engine (mass/ kWh). However, NOx emissions remained unchanged, and emissions of other pollutants were actually increased forthe LD vehicles with +26% for hydrocarbons (HC), +18% for CO, and +25% for PM-associated benzo[a]pyrene toxicity equivalents (TEQ). In contrast, CO (-32%), TEQ (-14%), and NOx (-6%) were reduced by the emulsion for the HD engine, and only hydrocarbons were slightly increased (+16%). Whereas the Cerium-based additive was inefficient in the HD engine for all emissions except for TEQ (-39%), it markedly reduced all emissions for the LD vehicles (PM -13%, CO -18%, HC -26%, TEQ -25%) except for NOx, which remained unchanged. The presented data indicate a strong potential for reductions in PM emissions from current diesel engines by optimizing the fuel composition. 相似文献
240.
Pier Giorgio Peiretti Claudio Medana Sonja Visentin Valeria Giancotti Valentina Zunino Giorgia Meineri 《Food chemistry》2011
The aim of this research was to determine the content of the histidinic antioxidants, advanced glycation end products (pentosidine) and thiobarbituric acid reactive substance (TBARS) in the meat from different animal species. Carnosine, anserine, homocarnosine and pentosidine were quantified by HPLC/MS, while TBARS was determined by photometric measurements. The total CRCs (carnosine + anserine + homocarnosine) content was in the increasing order: beef < rabbit < pork < horse < chicken < turkey. The analysis showed traces of pentosidine above the instrumental determination limits in all the meat samples, while the susceptibility of these meat to lipid oxidation decreased from beef to chicken, with the exception of turkey meat, which presented a high TBARS content towards even though its total CRCs was the highest. The structure of homocarnosine was elucidated by high resolving power multistage mass spectrometry. 相似文献