Period Used (period + used)

Distribution by Scientific Domains


Selected Abstracts


Effect of a 1-month vs. a 12-month reference period on responses to the 14-item Oral Health Impact Profile

EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 3 2007
Saila Sutinen
The length of the reference period used in surveys of subjective oral health may have a marked influence on the responses obtained. We aimed to evaluate the effect of a 1-month (RP-1) vs. a 12-month (RP-12) reference period in the Oral Health Impact Profile (OHIP-14) questionnaire. Using a randomized cross-over design, RP-1 and RP-12 OHIP-14 questionnaires were administered, 1 month apart, to two samples of Finnish adults, namely people awaiting orthognathic surgery (n = 104) and non-patient workers (n = 111). The effect of the reference period was computed by subtracting RP-1 OHIP-14 severity scores from RP-12 OHIP-14 severity scores (,RP). Potential order effects were assessed by comparing ,RP between groups completing the RP-1 vs. the RP-12 questionnaire first. Mean OHIP-14 severity scores were slightly higher when the RP-12 questionnaire was administered first, but mean ,RP values were below the value of 2.5 considered clinically meaningful, and all 95% confidence intervals for ,RP included zero. No order effects in the OHIP-14 severity scores were observed. Therefore, although a standardized reference period of 12 months is recommended, in population surveys the use of a shorter reference period does not appear to influence responses. [source]


The surface radiation budget over North America: gridded data assessment and evaluation of regional climate models

INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 15 2009
Marko Markovic
Abstract While surface station observations of downwelling radiation offer accuracy at high temporal resolution, they do not easily allow an evaluation of model surface radiation budgets (SRB) over a wide geographical area. We evaluate three gridded SRB data sets against detailed observations from six surface radiation sites from the US surface radiation (SURFRAD) network. We subsequently use the most accurate surrogate observational data set for evaluation of model-simulated SRB. The data sets assessed are: ERA40,reanalysis of European Centre for Medium-Range Weather Forecasts (ECMWF), North American Regional Reanalysis (NARR),regional reanalysis of National Centres for Environmental Prediction (NCEP) and the surface radiative budget (SRB) from the International Satellite Cloud Climatology Project (ISCCP). Due to varying constraints with respect to temporal coverage of each data set, the evaluation period used in this study is 1996,2001, inclusive. The ERA40 downwelling longwave radiation (DLR) appears the most accurate surrogate observation, while both ERA40 and ISCCP show accurate results when the incoming shortwave radiation (ISR) is considered across the annual cycle. Winter DLR is less accurate in ISCCP with a positive bias and lack of very low (<200 Wm,2) flux values. The NARR SRB shows a large positive bias in the ISR throughout the annual cycle, linked to a significant underestimate of cloud cover. The ERA40 data are subsequently used to evaluate the simulated SRB in three regional climate models across North America. With respect to solar radiation, cloud cover biases are seen to be crucial, while for longwave fluxes both cloud fraction and in-cloud water content are important to simulate correctly. Inclusion of trace gases beyond H2O, CO2 and O3 appears necessary for an accurate calculation of clear-sky longwave radiation. Error compensation frequently occurs between the various components contributing to a model total-sky SRB. This is important to consider when trying to identify the underlying causes of errors in the simulated total SRB. Copyright © 2009 Royal Meteorological Society [source]


Influence of growth stage and postharvest storage on ascorbic acid and carotenoid content and visual quality of baby spinach (Spinacia oleracea L.)

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 3 2006
Sara ÅM Bergquist
Abstract To investigate the variations in quality with growth stage and postharvest storage, spinach was sown on three occasions. For each occasion, the spinach was harvested at three growth stages at 6-day intervals. The second stage corresponded to a growth period used for baby spinach by commercial growers. After harvest, the leaves were stored in polypropylene bags at 2 °C or 10 °C. The highest ascorbic acid content in fresh material was found at stage I. During storage, the ascorbic acid content decreased considerably and the dehydroascorbic acid/vitamin C ratio increased. Storage at 2 °C gave a smaller reduction in ascorbic acid content than storage at 10 °C. Total carotenoid content increased or remained stable during storage. Lutein was the major carotenoid, making up about 39% of the total carotenoid content, followed by violaxanthin, ,-carotene and neoxanthin. Visual quality decreased during storage in most cases, and was correlated to initial ascorbic acid and dry matter contents. The initial AA content might therefore be used as a parameter for predicting the shelf-life of baby spinach. The results also indicate that by harvesting baby spinach a few days earlier than the current commercial stage of harvest the postharvest visual quality and nutritional quality may be improved. Copyright © 2005 Society of Chemical Industry [source]


Systemic vitamin C and vitamin E do not prevent photoprovocation test reactions in polymorphous light eruption

PHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 2 2000
B. Eberlein-König
The possible influence of oxidative stress is discussed in the pathogenesis of polymorphous light eruption (PLE). A double-blind, placebo-controlled study of prophylactic treatment with systemic administration of vitamin C (3 g/d) and E (1500 IU/d) for 8 days was undertaken in 9 patients with PLE (verum, n=4; placebo, n=5). Evaluation of the maximal effects after photoprovocation before and after intake of the antioxidants revealed a reduction of most skin reactions (overall skin reaction, papules/vesicles) in both groups with marked differences in the placebo group. The antioxidants in the doses given and over the time period used did not influence the development of PLE, but might interfere with immunosuppressive effects of repeated photoprovocation tests. [source]