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41.
Heidi?Taylor Kirsten?Webster Andrew?R.?Gray Siew?Ling?Tey Alex?Chisholm Karl?Bailey Shivani?Kumari Rachel?C.?BrownEmail author 《European journal of nutrition》2018,57(8):2771-2783
Purpose
Recommendations to soak nuts prior to consumption to reduce phytate concentrations and improve gastrointestinal tolerance have received much attention in the popular press. This is despite no supporting scientific evidence for the practice. There is also a lack of information about how soaking nuts might affect consumer acceptability. This study primarily assessed the effects of soaking almonds on consumer acceptance and secondly assessed effects on gastrointestinal tolerance.Methods
In this 8-week randomised crossover trial, 76 participants were allocated in balanced order to receive 30 g/day of four different preparations of almonds for 12 days: whole unsoaked, whole soaked, sliced unsoaked, and sliced soaked. Ratings of overall liking, desire to consume, and likelihood of future consumption, and severity of gastrointestinal symptoms were measured daily on visual analogue scales. The phytate concentrations were measured in all four nut types using high-performance liquid chromatography.Results
Mean acceptance ratings of all nut types were above the neutral point indicating they were acceptable. However, sliced soaked almonds were rated significantly lower overall for all three acceptance scales compared to the other treatments (all P ≤ 0.003). The sliced unsoaked almonds were rated lower than both whole nut treatments (all P ≤ 0.006), while there were no significant differences between the two whole nut treatments (all P ≥ 0.511). Gastrointestinal symptoms were minimal, but flatulence was rated significantly higher for all time points combined for soaked whole nuts compared to unsoaked whole nuts (P = 0.005). Compared to the whole unsoaked nuts (mean [SD] 531 [9] mg/100 g), phytate concentration was higher for the whole soaked almonds (563 [38] mg/100 g, P = 0.016), with no evidence of a difference for the sliced soaked almonds (548 [27] mg/100 g, P = 0.197) and no difference between the soaked forms (P = 0.262).Conclusions
This research supports previous results suggesting nuts, including different forms, are an acceptable food. They are also well tolerated gastrointestinally, but soaking does not improve gastrointestinal tolerance or acceptance as claimed in the lay literature.42.
Ambinintsoa H. Ralaidovy Abdulgafoor M. Bachani Jeremy A. Lauer Taavi Lai Dan Chisholm 《Cost effectiveness and resource allocation : C/E》2018,16(1):59
Background
Road safety has been receiving increased attention through the United Nations Decade of Action on Road Safety, and is also now specifically addressed in the sustainable development goals 3.6 and 11.2. In an effort to enhance the response to Road Traffic Injuries (RTIs), this paper aims to examine the cost effectiveness of proven preventive interventions and forms part of an update of the WHO-CHOICE programme.Methods
Generalized cost-effectiveness analysis (GCEA) approach was used for our analysis. GCEA applies a null reference case, in which the effects of currently implemented interventions are subtracted from current rates of burden, in order to identify the most efficient package of interventions. A population model was used to arrive at estimates of intervention effectiveness. All heath system costs required to deliver the intervention, regardless of payer, were included. Interventions are considered to be implemented for 100 years. The analysis was undertaken for eastern sub-Saharan Africa and Southeast Asia.Results
In Southeast Asia, among individual interventions, drink driving legislation and its enforcement via random breath testing of drivers at roadside checkpoints, at 80% coverage, was found to be the most cost-effective intervention. Moreover, the combination of “speed limits?+?random breath testing?+?motorcycle helmet use”, at 90% coverage, was found to be the most cost-effective package. In eastern sub-Saharan Africa, enforcement of speed limits via mobile/handheld cameras, at 80% coverage, was found to be the most cost-effective single intervention. The combination of “seatbelt use?+?motorcycle helmet use?+?speed limits?+?random breath testing” at 90% coverage was found to be the most cost-effective intervention package.Conclusion
This study presents updated estimates on cost-effectiveness of practical, evidence-based strategies that countries can use to address the burden of RTIs. The combination of individual interventions that enforces simultaneously multiple road safety measures are proving to be the most cost-effective scenarios. It is important to note, however, that, in addition to enacting and enforcing legislation on the risk factors highlighted as part of this paper, countries need to have a coordinated, multi-faceted strategy to improve road safety.43.
Jhy-Charm Soo Eun Gyung Lee Ryan F. LeBouf Michael L. Kashon William Chisholm Martin Harper 《Journal of occupational and environmental hygiene》2018,15(4):351-360
The objective of this present study was to evaluate the performance of a portable gas chromatograph-photoionization detector (GC-PID), under various test conditions to determine if it could be used in occupational settings. A mixture of 7 volatile organic compounds (VOCs)—acetone, ethylbenzene, methyl isobutyl ketone, toluene, m-xylene, p-xylene, and o-xylene—was selected because its components are commonly present in paint manufacturing industries. A full-factorial combination of 4 concentration levels (exposure scenarios) of VOC mixtures, 3 different temperatures (25°C, 30°C, and 35°C), and 3 relative humidities (RHs; 25%, 50%, and 75%) was conducted in a full-size controlled environmental chamber. Three repetitions were conducted for each test condition allowing for estimation of accuracy. Time-weighted average exposure data were collected using solid sorbent tubes (Anasorb 747, SKC Inc.) as the reference sampling medium. Calibration curves of Frog-4000 using the dry gases showed R2 > 0.99 for all analytes except for toluene (R2 = 0.97). Frog-4000 estimates within a test condition showed good consistency for the performance of repeated measurement. However, there was ~41–64% reduction in the analysis of polar acetone with 75% RH relative to collection at 25% RH. Although Frog-4000 results correlated well with solid sorbent tubes (r = 0.808–0.993, except for toluene) most of the combinations regardless of analyte did not meet the <25% accuracy criterion recommended by NIOSH. The effect of chromatographic co-elution can be seen with m, p-xylene when the results are compared to the sorbent tube sampling technique with GC-flame ionization detector. The results indicated an effect of humidity on the quantification of the polar compounds that might be attributed to the pre-concentrator placed in the selected GC-PID. Further investigation may resolve the humidity effect on sorbent trap with micro GC pre-concentrator when water vapor is present. Although this instrument does not fulfill the accuracy criterion specified in the NIOSH technical report No. 2012–162, it can be used as a screening tool for range finding monitoring with dry gases calibration in the occupational setting rather than compliance monitoring. 相似文献
44.
MacKenzie C. Ronald Green Douglas S. T. Chisholm Mary F. Waldman Seth A. 《HSS journal》2020,16(1):195-199
HSS Journal ® - 相似文献
45.
46.
47.
J B Foley R J Chisholm A A Common A Langer P W Armstrong 《American heart journal》1992,124(5):1174-1180
The frequency, clinical pattern, and timing of recurrent angina following successful single-lesion percutaneous transluminal coronary angioplasty (PTCA) was assessed in a consecutive group of 104 patients with stable angina and in 85 with unstable angina. In addition, the relationship between lesion morphology and angiographic features and the pattern of recurrent angina was determined. Restenosis, defined as recurrence of symptoms with > 50% stenosis at the site of PTCA, occurred in 25 (24%) of the stable group and in 23 (27%) of the unstable group (p = NS). The pattern of angina at repeat presentation was aggressive in nature in 8% of the stable group and in 48% of the unstable group (p = 0.002). The time interval between the recurrence of symptoms and repeat coronary angiogram or PTCA was longer in the nonaggressive group than in the aggressive group, 16 +/- 12.1 and 5 +/- 6.8 weeks, respectively (p < 0.003). The key factors predicting the recurrent angina pattern identified by multiple logistic regression analysis were the angina status pre-PTCA (p = 0.001) and the presence of double-vessel disease (p = 0.01). An aggressive pattern of angina at the time of restenosis is frequent in patients with unstable angina at the time of PTCA, and close post-PTCA surveillance is necessary in these patients. 相似文献
48.
49.
L. G. Cena M. J. Keane W. P. Chisholm S. Stone M. Harper B. T. Chen 《Journal of occupational and environmental hygiene》2014,11(12):771-780
Welders are exposed to high concentrations of nanoparticles. Compared to larger particles, nanoparticles have been associated with more toxic effects at the cellular level, including the generation of more reactive oxygen species activity. Current methods for welding-fume aerosol exposures do not differentiate between the nano-fraction and the larger particles. The objectives of this work are to establish a method to estimate the respiratory deposition of the nano-fraction of selected metals in welding fumes and test this method in a laboratory setting. Manganese (Mn), Nickel (Ni), Chromium (Cr), and hexavalent chromium (Cr(VI)) are commonly found in welding fume aerosols and have been linked with severe adverse health outcomes. Inductively coupled plasma mass spectrometry (ICP-MS) and ion chromatography (IC) were evaluated as methods for analyzing the content of Mn, Ni, Cr, and Cr(VI) nanoparticles in welding fumes collected with nanoparticle respiratory deposition (NRD) samplers. NRD samplers collect nanoparticles at deposition efficiencies that closely resemble physiological deposition in the respiratory tract. The limits of detection (LODs) and quantitation (LOQs) for ICP-MS and IC were determined analytically. Mild and stainless steel welding fumes generated with a robotic welder were collected with NRD samplers inside a chamber. LODs (LOQs) for Mn, Ni, Cr, and Cr(VI) were 1.3 μg (4.43 μg), 0.4 μg (1.14 μg), 1.1 μg (3.33 μg), and 0.4 μg (1.42 μg), respectively. Recovery of spiked samples and certified welding fume reference material was greater than 95%. When testing the method, the average percentage of total mass concentrations collected by the NRD samplers was ~30% for Mn, ~50% for Cr, and ~60% for Ni, indicating that a large fraction of the metals may lie in the nanoparticle fraction. This knowledge is critical to the development of toxicological studies aimed at finding links between exposure to welding fume nanoparticles and adverse health effects. Future work will involve the validation of the method in workplace settings.
[Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resource: Digestion, extraction, and analysis procedures for nylon mesh screens.] 相似文献