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51.
OBJECTIVE: To examine the influence of individual- and area-level socio-economic characteristics on food choice behaviour and dietary intake. SETTING: The city of Eindhoven in the south-east Netherlands. DESIGN: A total of 1339 men and women aged 25-79 years were sampled from 85 areas (mean number of participants per area = 18.4, range 2-49). Information on socio-economic position (SEP) and diet was collected by structured face-to-face interviews (response rate 80.9%). Individual-level SEP was measured by education and household income, and area-level deprivation was measured using a composite index that included residents' education, occupation and employment status. Diet was measured on the basis of (1) a grocery food index that captured compliance with dietary guidelines, (2) breakfast consumption and (3) intakes of fruit, total fat and saturated fat. Multilevel analyses were performed to examine the independent effects of individual- and area-level socio-economic characteristics on the dietary outcome variables. RESULTS: After adjusting for individual-level SEP, few trends or significant effects of area deprivation were found for the dietary outcomes. Significant associations were found between individual-level SEP and food choice, breakfast consumption and fruit intake, with participants from disadvantaged backgrounds being less likely to report food behaviours or nutrient intakes consistent with dietary recommendations. CONCLUSIONS: The findings suggest that an individual's socio-economic characteristics play a more important role in shaping diet than the socio-economic characteristics of the area in which they live. In this Dutch study, no independent influence of area-level socio-economic characteristics on diet was detected, which contrasts with findings from the USA, the UK and Finland. 相似文献
52.
Ménot G Bard E Rostek F Weijers JW Hopmans EC Schouten S Sinninghe Damsté JS 《Science (New York, N.Y.)》2006,313(5793):1623-1625
During the Last Glacial Maximum, the sea-level lowstand combined with the large extent of the Fennoscandian and British ice sheets led to the funneling of European continental runoff, resulting in the largest river system that ever drained the European continent. Here, we show an abrupt and early reactivation of the European hydrological cycle at the onset of the last deglaciation, leading to intense discharge of the Channel River into the Bay of Biscay. This freshwater influx, probably combined with inputs from proglacial or ice-dammed lakes, dramatically affected the hydrology of the region, both on land and in the ocean. 相似文献
53.
Globalization causes plant production systems to be increasingly threatened by invasive pests and pathogens. Much research is devoted to support management of these risks. Yet, the role of growers' perceptions and behavior in risk management has remained insufficiently analyzed. This article aims to fill this gap by addressing risk management of invasive pathogens from a sociopsychological perspective. An analytical framework based on the Theory of Planned Behavior was used to explain growers' decisions on voluntary risk management measures. Survey information from 303 Dutch horticultural growers was statistically analyzed, including regression and cluster analysis. It appeared that growers were generally willing to apply risk management measures, and that poor risk management was mainly due to perceived barriers, such as high costs and doubts regarding efficacy of management measures. The management measures applied varied considerably among growers, depending on production sector and farm-specific circumstances. Growers' risk perception was found to play a role in their risk management, although the causal relation remained unclear. These results underscore the need to apply a holistic perspective to farm level management of invasive pathogen risk, considering the entire package of management measures and accounting for sector- and farm-specific circumstances. Moreover, they demonstrate that invasive pathogen risk management can benefit from a multidisciplinary approach that incorporates growers' perceptions and behavior. 相似文献
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57.
Katarina EA Nostell Birgitta Essén-Gustavsson Johan T Br?jer 《Acta veterinaria Scandinavica》2012,54(1):7
Background
The branched chain amino acid leucine is a potent stimulator of insulin secretion. Used in combination with glucose it can increase the insulin response and the post exercise re-synthesis of glycogen in man. Decreased plasma amino acid concentrations have been reported after intravenous or per oral administration of leucine in man as well as after a single per oral dose in horses. In man, a negative correlation between the insulin response and the concentrations of isoleucine, valine and methionine have been shown but results from horses are lacking. This study aims to determine the effect of repeated per oral administration with a mixture of glucose and leucine on the free amino acid profile and the insulin response in horses after glycogen-depleting exercise.Methods
In a crossover design, after a glycogen depleting exercise, twelve Standardbred trotters received either repeated oral boluses of glucose, 1 g/kg body weight (BW) at 0, 2 and 4 h with addition of leucine 0.1 g/kg BW at 0 and 4 h (GLU+LEU), or repeated boluses of water at 0, 2 and 4 h (CON). Blood samples for analysis of glucose, insulin and amino acid concentrations were collected prior to exercise and over a 6 h post-exercise period. A mixed model approach was used for the statistical analyses.Results
Plasma leucine, isoleucine, valine, tyrosine and phenylalanine concentrations increased after exercise. Post-exercise serum glucose and plasma insulin response were significantly higher in the GLU+LEU treatment compared to the CON treatment. Plasma leucine concentrations increased after supplementation. During the post-exercise period isoleucine, valine and methionine concentrations decreased in both treatments but were significantly lower in the GLU+LEU treatment. There was no correlation between the insulin response and the response in plasma leucine, isoleucine, valine and methionine.Conclusions
Repeated post-exercise administration with a mixture of leucine and glucose caused a marked insulin response and altered the plasma amino acid profile in horses in a similar manner as described in man. However, the decreases seen in plasma amino acids in horses seem to be related more to an effect of leucine and not to the insulin response as seen in man. 相似文献58.
Estimation of stem attributes using a combination of terrestrial and airborne laser scanning 总被引:2,自引:0,他引:2
Eva Lindberg Johan Holmgren Kenneth Olofsson Håkan Olsson 《European Journal of Forest Research》2012,131(6):1917-1931
Properties of individual trees can be estimated from airborne laser scanning (ALS) data provided that the scanning is dense enough and the positions of field-measured trees are available as training data. However, such detailed manual field measurements are laborious. This paper presents new methods to use terrestrial laser scanning (TLS) for automatic measurements of tree stems and to further link these ground measurements to ALS data analyzed at the single tree level. The methods have been validated in six 80 × 80 m field plots in spruce-dominated forest (lat. 58°N, long. 13°E). In a first step, individual tree stems were automatically detected from TLS data. The root mean square error (RMSE) for DBH was 38.0 mm (13.1 %), and the bias was 1.6 mm (0.5 %). In a second step, trees detected from the TLS data were automatically co-registered and linked with the corresponding trees detected from the ALS data. In a third step, tree level regression models were created for stem attributes derived from the TLS data using independent variables derived from trees detected from the ALS data. Leave-one-out cross-validation for one field plot at a time provided an RMSE for tree level ALS estimates trained with TLS data of 46.0 mm (15.4 %) for DBH, 9.4 dm (3.7 %) for tree height, and 197.4 dm3 (34.0 %) for stem volume, which was nearly as accurate as when data from manual field inventory were used for training. 相似文献
59.
A collection of seeds from five Acacia species was made in Egypt in 1856. Since then, the seeds have been stored at room temperature in different Swedish museums.
Due to the extreme longevity within the seeds of Acacia and related species, germination tests were performed on the now 151-year old seed. Seeds of two of the five species tested
germinated. The first, Acacia farnesiana (L.) Willd., had two seeds germinate, and Acacia melanoxylon R. Br. ex Ait. f. had one seed germinate. In addition, DNA was extracted from the aged seed and DNA preservation was analyzed.
Four of the tested species displayed well preserved DNA, whereas DNA from Albizia lebbeck (L.) Benth. showed signs of degradation. The 151-year longevity of the Acacia seeds is among the longest of dry-stored seeds reported. Several independent studies now report on extreme survival capacity
for Acacia and related genera suggesting that these genera are suitable for studies on the characteristics of seeds with long storage
performance. The results also demonstrate that herbaria and seed collections stored in museums and institutional depositories
can be alternate sources of plants genetic material and should be given conservation attention. 相似文献
60.
Anouk Schurink Sabrina C. Podesta Bart J. Ducro Johan A.M. van Arendonk Klaas Frankena 《Veterinary journal (London, England : 1997)》2013,195(3):382-384
Insect bite hypersensitivity (IBH) is an equine skin allergy caused by bites of Culicoides spp. and impacts on the welfare of affected horses. The aim of this study was to identify and quantify risk factors for IBH. Data from 3453 Friesian horse mares and 7074 Shetland pony mares scored for IBH by inspectors during obligatory foal inspections were analysed using breed-specific multivariable logistic regression models. The combined effect of month and year of scoring, Province and inspector were significantly associated with IBH in both breeds. In Shetland pony mares, withers height and coat colour were also significantly associated with IBH, while body condition had a nearly significant effect. The outcomes from this study on risk factors might contribute to the development of more efficient measures to reduce the prevalence of IBH. 相似文献