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1.
PurposeElectronic data capture is becoming increasingly common for collecting real-time patient responses. The purpose of this study was to investigate compliance with a daily electronic questionnaire regarding night-time contact lens visual performance.MethodForty-eight subjects (34 females) were fit and dispensed two contralateral pairs of soft contact lenses (SCLs) for one week each. Subjects were sent a nightly e-mail at 8 PM containing a secure, individualized link to an electronic questionnaire asking 30 questions of varying response styles (e.g., multiple choice, short answer, etc.) about SCL visual performance. Subjects were instructed to complete the questionnaire before going to bed.ResultsThe overall completion rate based on 676 electronic questionnaires was 95.1%. Of these, only 3.6% were completed late (<24 h). The percentage of subjects completing all questionnaires was significantly higher on weekdays (96.5%; Sunday through Thursday) than on weekends (91.1%; Friday and Saturday). Fisher exact tests indicated no significant association with gender for either weekday (p = 0.25) or weekend (p = 0.73). Although odds ratio estimates suggested that participants 23 and older were more likely to complete the questionnaire (weekday: OR = 4.39, p = 0.10; weekend: OR = 2.93, p = 0.19), these associations did not reach statistical significance.ConclusionsE-mail based questionnaires provide an effective method for acquiring time specific responses, making them a viable clinical and research tool. The day(s) of the week on which assessments occur need to be strongly considered, as on-time compliance may be affected on weekend evenings, or possibly situations in which a typical schedule may not be followed.  相似文献   

2.
Behavioral observations are important in detecting illness, injury, and reproductive status as well as performance of normal behaviors. However, conducting live observations in extensive systems, such as pasture-based dairies, can be difficult and time consuming. Activity monitors, such as those created for use with automatic milking systems (AMS), have been developed to automatically and remotely collect individual behavioral data. Each cow wears a collar transponder for identification by the AMS, which can collect data on individual activity and rumination. The first aim of this study was to examine whether cow activity levels as reported by the AMS activity monitor (ACT) are accurate compared with live observations and previously validated pedometers [IceQube (IQ), IceRobotics, Edinburgh, UK]. The second aim of the study was to determine if the AMS rumination monitors (RUM) provide an accurate account of time spent ruminating compared with live observations. Fifteen lactating Holstein cows with pasture access were fitted with ACT, RUM, and IQ. Continuous focal observations (0600–2000 h) generated data on lying and active behaviors (standing and walking), as well as rumination. Activity recorded by live observation and IQ included walking and standing, whereas IQ steps measured cow movement (i.e., acceleration). Active behaviors were analyzed separately and in combination to ascertain exactly what behavioral components contributed to calculation of ACT “activity.” Pearson correlations (rp) were computed between variables related to ACT, RUM, IQ, and live observations of behavior. A linear model was used to assess significance differences in the correlation coefficients of the 4 most relevant groups of variables. Significant but moderate correlations were found between ACT and observations of walking (rp = 0.61), standing (rp = 0.46), lying (rp = −0.57), and activity (rp = 0.52), and between ACT and IQ steps (rp = 0.75) and activity (rp = 0.58) as well as between RUM and observations of rumination (rp = 0.65). These data indicate that ACT and RUM do reflect cow walking and rumination, respectively, but not with a high degree of accuracy, and lying cannot be distinguished from standing.  相似文献   

3.
Lead is a component of tobacco and tobacco smoke. We examined the relationship between current, former, and passive smoking and blood lead levels in a nationally representative sample of 16,458 U.S. adults, aged 17 years or older, who participated in the Third National Health and Nutrition Examination Survey (1988-1994). We used linear and logistic regression modeling, adjusting for known covariates, to determine the relationship between smoking and blood lead levels. Geometric mean blood lead levels were 1.8 microg/dl, 2.1 microg/dl, and 2.3 microg/dl in never-smokers with no, low, and high cotinine levels, respectively. Levels were 2.9 microg/dl in former smokers and 3.5 microg/dl in current smokers. The adjusted linear regression model showed that geometric mean blood lead levels were 30% higher (95% CI = 24%-36%) in adults with high cotinine levels than they were in those with no detectable cotinine. Active and passive smoking is associated with increased blood lead levels in U.S. adults.  相似文献   

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The electronic equipment used on farms can be creatively co-opted to collect data for which it was not originally designed. In the current study, we describe 2 novel algorithms that harvest data from electronic feeding equipment and data loggers used to record standing and lying behavior, to estimate the time that dairy cows spend away from their pen to be milked. Our 2 objectives were to (1) measure the ability of the first algorithm to estimate the time cows spend away from the pen as a group and (2) determine the capability of a second algorithm to estimate the time it takes for individual cows to return to their pen after being milked. To achieve these objectives, we conducted 2 separate experiments: first, to estimate group time away, the feeding behavior of 1 pen of 20 Holstein cows was monitored electronically for 1 mo; second, to measure individual latency to return to the pen, feeding and lying behavior of 12 healthy Holstein cows was monitored electronically from parturition to 21 d in milk. For both experiments, we monitored the time each individual cow exited the pen before each milking and when she returned to the pen after milking using video recordings. Estimates generated by our algorithms were then compared with the times captured from the video recordings. Our first algorithm provided reliable pen-based estimates for the minimum time cows spent away from the pen to be milked in the morning [coefficient of determination (R2) = 0.92] and afternoon (R2 = 0.96). The second algorithm was able to estimate of the time it took for individual cows to return to the pen after being milked in the morning (R2 = 0.98), but less so in the afternoon (R2 = 0.67). This study illustrates how data from electronic systems used to assess feeding and lying behavior can be mined to estimate novel measures. New work is now required to improve the estimates of our algorithm for individuals, for example by adding data from other electronic monitoring systems on the farm.  相似文献   

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The asymptotic decrease in lead concentration c in roadside crops according to the distance d from the edge of an isolated straight road can be described empirically by means of the three-parameter exponential function c=A+B exp (-Cd). Least-squares non-linear regression allows the estimation of the parameters A, B and C. The validity of the function was tested by fitting it to a few sets of observations on unwashed wine grape and leaf samples. An analysis of residuals was performed, considering in particular the extent of the normality of their distribution. The function was also applied to a few sets of data of low sample size to examine the effect of washing on the parameters of the function.  相似文献   

10.
This article reports the findings of an international survey of nanomaterials firms and laboratories regarding their environmental health and safety (EHS) programs, engineering controls, personal protective equipment (PPE), exposure monitoring, waste disposal, product stewardship, and risk beliefs. While many participants reported not believing that nanomaterials pose special risks, nanospecific EHS programs were still widely reported. Most nanospecific EHS programs appeared to build from general EHS programs but included nanospecific workplace engineering controls and recommendations for clothing, gloves, eye protection, and respirators. Organizations with nanospecific EHS programs also reported providing product (safe use) guidance to consumers. However, workplace monitoring and nanospecific waste disposal were uneven and were only associated with the subset of organizations believing in special risks. A majority of organizations expressed a need for more toxicological information and EHS guidance. Overall, this study suggests that nanomaterials firms and laboratories are already attentive to nanospecific EHS and product stewardship issues. However, improved risk communication is needed to further the implementation of related programs. Organizations that are wholly inattentive to EHS would likely engage in nanospecific EHS upon implementing a staffed, general EHS program.  相似文献   

11.
ABSTRACT

Acrylamide is a contaminant that can form in certain plant-based foods during high-temperature cooking. From 2011–2015, the Food and Drug Administration conducted extensive sampling and analyses of acrylamide in foods, as a follow-up to surveys from 2002–2006. We compared acrylamide occurrence data and exposure estimates based on 2011–2015 data with data and exposure estimates from 2002–2006. Acrylamide levels in selected food categories generally did not decrease significantly in 2011–2015 compared with 2002–2006. However, significant decreases in acrylamide concentrations were observed for potato chips and crackers, which may be related to the availability and use of mitigation techniques for reducing acrylamide in foods. Mean dietary intake for those 2 years and older based on 2011–2015 data was 0.36 µg/kg bw/day, comparable to the 0.44 µg/kg bw/day reported by FDA in 2006. French fries and potato products, breakfast cereal, cookies, potato chips, and crackers continue to be the greatest contributors to dietary intake of acrylamide. Infant snack foods were identified as an important contributor to acrylamide intake relative to infant jarred foods. The continued presence of acrylamide in food suggests that manufacturers and governments should continue to pursue efforts to reduce acrylamide in foods that are important contributors to acrylamide intake.  相似文献   

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ABSTRACT

It is important to explore new sources of natural additives because the demand for these compounds by consumers is increasing. These products also provide health benefits and help in food preservation. An unexplored source of nutrients and antioxidant compounds is rosehip, the fleshy fruit of roses. This work compares the antioxidant compound (vitamin C, neutral phenols and acidic phenols) content of four Rosa species rosehips: R. pouzinii, R. corymbifera, R. glauca and R. canina from different geographical zones. Results show quantitative variability in ascorbic acids and neutral phenols content, and quantitative and qualitative differences in acidic phenol content, depending on species. Vitamin C concentration was highly variable depending on species, R. canina being the one with the highest concentration and R. pouzinii the one with the lowest content. Variability was found in total neutral polyphenols concentration and a correlation between freshness of the rosehips and concentration of neutral polyphenols was also found. Significant differences were found in the acidic phenols content among the studied species. Generally antioxidant activity was higher in the vitamin C fraction.  相似文献   

14.
We analyzed pooled data from two comparable randomized placebo-controlled clinical trials of bupropion pharmacotherapy for smoking cessation for which data on DRD2 Taq1A genotype were available. A total of 722 smokers across the two trials were randomized to 10 weeks of sustained-release bupropion hydrochloride or placebo. General estimating equation analysis demonstrated a significant gene x drug interaction (B = 0.87, SE = 0.34, p = .009). Smokers with the A2/A2 genotype using bupropion were more than three times as likely, relative to placebo, to be abstinent at end of treatment (35.2% vs. 15.1%; OR = 3.25, 95% CI 2.00-5.28) and at 6 months of follow-up (26.7% vs. 12.2%; OR = 2.81, 95% CI 1.66-4.77), which was attenuated by 12 months (16.3% vs. 10.7%; OR = 1.70, 95% CI 0.95-3.05). We found no significant benefit of bupropion relative to placebo on smoking cessation outcomes at any time point in participants with A1/A1 or A1/A2 genotypes. These data suggest that bupropion may be effective for smoking cessation only in a subgroup of smokers with the DRD2 Taq1 A2/A2 genotype.  相似文献   

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Gum samples from six individual Combretum nigricans trees and two additional reference samples have been characterized. 13C Fourier-transform NMR spectra show that all have the same structure and confirm that the variations observed in their analytical parameters reflect only small fine-structural differences. NMR spectra also reveal that eight West African 'gum combretum' samples from reputable commercial sources originated from Combretum nigricans. This identification is important because gum combretum, which is not permitted as a food additive, has been exploited as an adulterant and misrepresented as gum arabic, for which not even the 1990 Revised Specification is sufficiently rigorous to detect such commercial deceptions. NMR spectroscopy has also shown that the rhamnose and uronic acid contents of gum combretum are located within internal polysaccharide chains. This explains the well-known difference in emulsification functionality between gum arabic, in which all rhamnose and uronic acid groups chain-terminal, and gum combretum which is, in addition, markedly hygroscopic and characterized commercially by its tendency to 'block' in transit and storage.  相似文献   

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An ammonia-oxidizing bacterium (strain YNSRA) was isolated from the rhizoplane of the reed (Phragmites communis) used in an aquaponics plant which is a wastewater treatment plant. Strain YNSRA was identified as Nitrosomonas communis by taxonomic studies. The hydroxylamine-cytochrome c reductase (HCR) of strain YNSRA was found to have a higher activity (25.60 u/mg) than that of Nitrosomonas europaea ATCC25978T (8.94 u/mg). Ribulose-1,5-bisphosphate carboxylase (RubisCO) activity was detected at very low levels in strain YNSRA, whereas strain ATCC25978T had definite activity.  相似文献   

18.
Molecular diagnostic ratios (MDRs)-the ratios of defined pairs of individual compounds-have been widely used as markers of different source categories of polycyclic aromatic hydrocarbons (PAHs). However, it is well-known that variations in combustion conditions and environmental degradation processes can cause substantial variability in the emission and degradation of individual compounds, potentially undermining the application of MDRs as reliable source apportionment tools. The United Kingdom produces a national inventory of atmospheric emissions of PAHs, and has an ambient air monitoring program at a range of rural, semirural, urban, and industrial sites. The inventory and the monitoring data are available over the past 20 years (1990-2010), a time frame that has seen known changes in combustion type and source. Here we assess 5 MDRs that have been used in the literature as source markers. We examine the spatial and temporal variability in the ratios and consider whether they are responsive to known differences in source strength and types between sites (on rural-urban gradients) and to underlying changes in national emissions since 1990. We conclude that the use of these 5 MDRs produces contradictory results and that they do not respond to known differences (in time and space) in atmospheric emission sources. For example, at a site near a motorway and far from other evident emission sources, the use of MDRs suggests "non-traffic" emissions. The ANT/(ANT + PHE) ratio is strongly seasonal at some sites; it is the most susceptible MDR to atmospheric processes, so these results illustrate how weathering in the environment will undermine the effectiveness of MDRs as markers of source(s). We conclude that PAH MDRs can exhibit spatial and temporal differences, but they are not valid markers of known differences in source categories and type. Atmospheric sources of PAHs in the UK are probably not dominated by any single clear and strong source type, so the mixture of PAHs in air is quickly "blended" away from the influence of the few major point sources which exist and further weathered in the environment by atmospheric reactions and selective loss processes.  相似文献   

19.
As part of an EU-funded project to assist in developing the production chain of meat from camelids in South America we have investigated the possibility of using an electronic nose to distinguish between the different types of meat of commercial interest. On-site monitoring of freshly cooked camelid meat using a Bloodhound electronic nose has been carried out in Peru and Bolivia. Sampling was carried out using inert, collapsible plastic bags. Linear discriminant analysis of data generated by the electronic nose classified the samples of meat. Some problems experienced in analysing the data relating to sample size are discussed.  相似文献   

20.

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   

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