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1.
Olive oil consumption and reduced incidence of hypertension: The SUN study   总被引:2,自引:0,他引:2  
Alonso A  Martínez-González MA 《Lipids》2004,39(12):1233-1238
Olive oil, a major component of the Mediterranean diet, has been associated in some small clinical trials and cross-sectional studies with a reduction in blood pressure. The objective of this study was to assess the association of olive oil consumption with the incidence of hypertension in an epidemiologic cohort, the Seguimiento Universidad de Navarra (SUN) study. The SUN Project is a prospective cohort study whose members are all university graduates. The recruitment and follow-up of participants is made using mailed questionnaires. Diet was assessed using a semiquantitative food frequency questionnaire previously validated in Spain, with 136 items. Outcomes of interest were newly diagnosed cases of hypertension, as reported by participants in the follow-up questionnaires. Logistic regression models were fit to assess the risk of hypertension associated with olive oil consumption. For the present analysis, we have taken in consideration the first 6,863 participants, with at least 2 yr of follow-up. After a median follow-up time of 28.5 mon, the cumulative incidence of hypereension was 4.7% in men and 1.7% in women. A lower risk of hypertension was observed among participants with a higher olive oil consumption at baseline, but the results were not statistically significant (P=0.13 for the linear trend test in the multivariate model). However, among men, the adjusted odds ratios (OR) (95% confidence intervals) of hypertension for the second to fifth quintiles of olive oil consumption, compared with the first quintile, were 0.55 (0.28–1.10), 0.75 (0.39–1.43), 0.32 (0.15–0.70), and 0.46 (0.23–0.94), respectively (P=0.02 for linear trend). No association was found between olive oil consumption and the risk of hypertension among women. In conclusion, in a Mediterranean population, we found olive oil consumption to be associated with a reduced risk of hypertension only among men. The lack of association observed among women might be attributed to the overall lower incidence of hypertension found among females and the resulting lower statistical power.  相似文献   
2.
The aim of this dynamic prospective follow-up study was to assess the association between olive oil consumption and the likelihood of weight gain or the incidence of overweight or obesity in a large Mediterranean cohort of 7,368 male and female Spanish university graduates (the SUN Project) who were followed for a median period of 28.5 mon. A validated Food Frequency Questionnaire was administered at baseline, and respondents also completed a follow-up questionnaire after 28.5 mon. Changes in participants' consumption of olive oil and their weight were assessed during follow-up. A higher baseline consumption of olive oil was associated with a lower likelihood of weight gain, although the differences were not statistically significant. The adjusted difference in weight gain (kg) was −0.16 [95% confidence interval (C1): −0.42 to +0.11] for participants in the upper quintile of olive oil consumption (median: 46 g/d) compared with those in the lowest quintile (median: 6 g/d). For participants with a high baseline consumption of olive oil whose olive oil consumption also increased during follow-up, we found a slightly increased but nonsignificant risk of incidence of over-weight or obesity (adjusted odds ratio=1.19, 95% C1: 0.73 to 1.95). Our study, carried out in a sample of free-living people, shows that a high amount of olive oil consumption is not associated with higher weight gain or a significantly higher risk of developing overweight or obesity in the context of the Mediterranean food pattern.  相似文献   
3.
This paper proposes a combined method for two-dimensional temperature and velocity measurements in liquid and gas flow using a schlieren system. Temperature measurements are made by relating the intensity level of each pixel in a schlieren image to the corresponding knife-edge position measured at the exit focal plane of the schlieren system. The same schlieren images were also used to measure the velocity of the fluid flow. The measurement is made by using particle image velocimetry (PIV). The PIV software used in this work analyzes motion between consecutive schlieren frames to obtain velocity fields. The proposed technique was applied to measure the temperature and velocity fields in the natural convection of water provoked by a heated rectangular plate.  相似文献   
4.
The objectives of this study were to compare the effectiveness of various washing treatments for reducing Escherichia coli O157:H7, Salmonella sp., and Listeria monocytogenes populations on orange surfaces and to measure the effect of some of these treatments in preventing the transfer of pathogens during juice extraction. Orange surfaces inoculated with L. monocytogenes or a mixture of E. coli O157:H7 and Salmonella Typhimurium were washed by water spray and then sprayed with or dipped in water at 80°C for 1 min, 70% ethanol for 15, 30, or 45 s or 1, 2, or 4 min, 2 or 4% lactic acid solution at 55°C for 15, 30, or 45 s or 1, 2, or 4 min, or 200 mg/liter hypochlorite at pH 6.5 or 10 for 15 s. The surviving populations of these pathogens on the oranges were enumerated after each treatment. In a further stage, the ability of these pathogens to be transferred to the juice during extraction was tested. Juice was obtained from inoculated oranges that were subjected to selected treatments using chlorine, lactic acid, ethanol, and hot water as described above, and then bacterial counts in orange juice were determined. The application of these treatments reduced the populations of pathogens on orange surfaces by 1.9 to >4.9 log, 1.9 to >4.6 log, and 1.4 to 3.1 log cycles for E. coli O157:H7, Salmonella Typhimurium, and L. monocytogenes, respectively. The treatments using hot water or lactic acid showed greater reductions than other treatments. The time, antimicrobial concentration, and form of application affected the bacterial reduction. All treatments resulted in undetectable counts in the juice. Nevertheless, pathogens were recovered by the enrichment-plating method. Treatment of oranges before juice extraction may reduce the risk associated with consuming orange juice.  相似文献   
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6.
The solvent selection methodology developed earlier by Gani et al. [Gani, R., Jiménez-González, C., & Constable, D. J. C. (2005). Method for selection of solvents for promotion of organic reactions. Computers and Chemical Engineering, 29, 1661–1676] has been extended to handle multi-step reaction systems as well as solvent substitution for specific reaction steps for existing processing systems. The problems were formulated based on the methodology guidelines, and solved using ICAS software tool [ICAS Documentation. (2003). Internal report. CAPEC, Department of Chemical Engineering, Technical University of Denmark]. Highly promising results were obtained, either in accordance with results previously published in the literature, or with industrial process data. This shows that the methodology has potential for application to complex reaction schemes as well as on the problems of solvent replacement.  相似文献   
7.
The growing interest in ubiquitous robotics has originated in the last years the development of a high variety of testbeds. This paper presents a survey on existing ubiquitous robotics testbeds comprising networked mobile robots and networks of distributed sensors, cameras and smartphones, among others. The survey provides an insight into the testbed design, internal behavior and use, identifying trends and existing gaps and proposing guidelines for testbed developers. The level of interoperability among different ubiquitous robotics technologies is used as the main conducting criterion of the survey. Other features analyzed include testbed architectures, target experiments and usability tools.  相似文献   
8.
Increased consumption of fruits and vegetables is linked to health benefits but also to an increase in the number of outbreaks of foodborne illness. To determine the effectiveness of different sanitizing treatments for reducing bacterial pathogens on fresh produce, fresh cantaloupes and bell peppers were harvested and inoculated with suspensions of Salmonella Typhimurium and Escherichia coli O157:H7. The inoculated fruits were treated with water wash alone or were washed and then waxed or rinsed with 200 mg/liter hypochlorite, 10% Ca(OH)2, or 2% lactic acid solutions applied by dipping for 15 s or spraying for 15 s. Preliminary experiments with chlorine treatments indicated that spraying with a 200, 600, or 1,000 mg/liter hypochlorite solution reduced populations of both pathogens by 2.1 to 2.6 and 1.5 to 2.1 log CFU for Salmonella Typhimurium and E. coli O157:H7, respectively. In general, no differences were observed between chlorine solutions without pH adjustment (pH 9.2) and those with pH adjusted to 6.0. When different wash regimes were applied to inoculated cantaloupes or bell peppers, water wash alone produced significantly lower counts of both pathogens on bell peppers in comparison to untreated controls. However, this reduction was not observed on cantaloupes, indicating a possible surface effect. Application of 2% L-lactic acid by spray was the treatment that resulted in the lowest bacterial counts on both cantaloupes and bell peppers. This treatment did not produce any deleterious change in the sensorial characteristics of the products tested. None of the pathogens studied was able to grow during refrigerated storage (5 degrees C for cantaloupes and 10 degrees C for bell peppers), although numbers close to the detection limit of the counting method were found in randomly tested individual samples at days 14 and 28 of storage, indicating that these pathogens can survive for long periods on the produce surface. These results indicate that selected produce commodities could be sanitized at the packing facility. However, these interventions should not be applied as a replacement for but only as a complement to good hygiene practices.  相似文献   
9.
In this work a new microwave-heating procedure is presented as a viable alternative for both the conventional and ultraviolet (UV) curing systems used in the natural stone industry. Both thermal simulations and experimental tests demonstrate that microwave energy highly reduces curing and storing times while maintaining the product's final quality. Several polymer mixtures have been obtained from commercial products and fillers for maximum microwave absorption and their complex permittivity has been properly measured. A continuous industrial microwave oven has been built specifically for this purpose and tested on Crema-Sierra Puerta marble samples and commercial epoxy and polyester resins.  相似文献   
10.
This work offers an overview of the state of the art and future state of environmental health in our country from a viewpoint of the impact of the commercial opening established in the Free Trade Agreement among Mexico, the USA, and Canada. In the first section of this work, we analyze the expected economic changes resulting from the implementation of the FTA and foretells the way in which those changes will influence the present environmental and epidemiologic profiles of this country in the medium and long term. The main changes predicted by the analysis are, in the epidemiologic context, the acceleration of the transference of occupational, consumption, environmental and population risks, characteristic of industrialized countries, to the country's polarized epidemiologic profile; and, in the environmental context, a transition consisting of a broadening and composition of the spectrum of pollutants, including and important lagging of bacteriologic control. The second section offers an analysis of the predicted response capacity facing the new environmental risk dynamics in the country, encompassing regulation, normativeness and enforcement of environmental and consumer protection, as well as obstacles found in health services to the implementation of surveillance, detection and treatment of health damages caused by environmental factors. The analysis of the organized social response to these problems discloses a relative flexibility of the normativeness and enforcement functions in comparison with our northern neighbors, a paramount factor for the possible transference of environmental risks, as well as the informational and research deficiency about environmental issues, basic elements for sustaining environmental health in the country, aiming at speeding up the development and transference of technologies for prevention, detection and management of environmental risks in the country, drawing upon the systematization of our experience and that of our neighbors. This speeding process ought to match, in the medium term, the velocity of risk transference produced by the commercial opening. In this way, the commercial integration of North America will become a favorable context for the development of the environmental health infrastructure of the country.  相似文献   
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