251 research outputs found
Development of a dynamic population model as a decision support system for Codling Moth (Cydia pomonella L) management
In 2004 RIMpro-Cydia was developed as a dynamic population model that simulates the
within-year biology of a local codling moth population. The model is meant to be used by
growers and advisors to optimize the control of codling moth populations in organic and
integrated managed orchards. The model is based on literature data and unpublished
research data. Fractional boxcar trains are used to mimic the dispersion in the
developmental processes. The model is run in real time on the data input of local weather
stations, starting on 1 January. The output of the model was compared with the results of
field observations in three years in an untreated orchard. In the years 2005 to 2007 the
progress in egg deposition as predicted by the model was in general agreement with the
field data. The start of the egg deposition period was predicted well. The end of the egg
deposition period was predicted when in the field about 10% of the eggs was still to be
laid. There was no consistency in the relation between cumulated pheromone trap catches
and the cumulative egg deposition as calculated from the field data
Atlantic Studies, « New Orleans in the Atlantic World » (I) / (II), vol. 5, n° 2 et 3, août - décembre 2008
De même que le paradigme braudélien a révolutionné la conception de la Méditerranée, en lui appliquant un cadre d’analyse historique élargi dans le temps et dans l’espace, l’histoire « atlantique » initiée par les travaux pionniers de Robert Palmer et Bernard Bailyn dans les années 1960 propose un changement de perspective centré sur l’étude de l’espace atlantique dans son ensemble. Cette approche a suscité de nombreux débats historiographiques, notamment à propos de la pertinence ou non de f..
Archeologisch onderzoek Evergem - Belzeelse Kerkweg / Ralingen 13 juli 2009 tot 10 november 2009
Dit rapport werd ingediend bij het agentschap samen met een aantal afzonderlijke digitale bijlagen. Een aantal van deze bijlagen zijn niet inbegrepen in dit pdf document en zijn niet online beschikbaar. Sommige bijlagen (grondplannen, fotos, spoorbeschrijvingen, enz.) kunnen van belang zijn voor een betere lezing en interpretatie van dit rapport. Indien u deze bijlagen wenst te raadplegen kan u daarvoor contact opnemen met: [email protected]
The influence of dairy consumption, sedentary behaviour and physical activity on bone mass in Flemish children : a cross-sectional study
Background: This cross-sectional study aimed to look for an association in young children between whole body bone mineral content (BMC) and areal bone mineral density (aBMD) and dairy consumption as well as sedentary behaviour (SB) and physical activity (PA). Moreover, we investigated whether there was an interaction effect between dairy consumption and SB or PA on BMC and aBMD.
Methods: Healthy children (6-12 years) were recruited from primary schools. Body composition and whole body bone mass were measured with dual-energy X-ray absorptiometry (DXA), dairy consumption was assessed with a food frequency questionnaire (FFQ) and PA and SB with an accelerometer. In total, 272 children underwent a DXA scan. Complete FFQ data were available for 264 children and 210 children had matching data from accelerometry recordings. Regression analyses were used to study the associations between (1) BMC and aBMD and (2) dairy consumption, SB and PA, adjusting for age, gender, pubertal stage, height and body composition.
Results: Dairy consumption was positively associated with whole body BMC and aBMD (absolute value as well as z-score), after correction for relevant confounders. SB was negatively associated with aBMD z-score and light PA was positively associated with both BMC and aBMD z-score. No gender differences were found. Moreover, an interaction effect between vigorous PA (VPA) and dairy consumption on aBMD (z-score) and BMC z-score was found, indicating that children with both high VPA and high dairy consumption had higher values for BMC and aBMD of the whole body minus the head.
Conclusion: Already at young age, PA and dairy consumption positively influence whole body bone mass assessed by DXA. Moreover, this study indicates clearly that SB is negatively associated with whole body bone density. Promoting regular PA and sufficient dairy consumption in young children and limiting SB can be expected to positively influence their bone mass accumulation, which can help in the prevention of osteoporosis later in life
The influence of dynamic tides on the apsidal-motion rate in close binaries with an evolved main-sequence star
The validity of the classical formula for the rate of secular apsidal motion
in close binaries is investigated for a sequence of models of a 5 solar mass
star ranging from the last stages of the C12 -> N14 reaction to the phase where
hydrogen is exhausted in the core. For binaries with short orbital periods, the
apsidal-motion rates predicted by the classical formula deviate from the rates
determined within the framework of the theory of dynamic tides due to the
effects of the compressibility of the stellar fluid and due to resonances of
dynamic tides with free oscillation modes of the component stars (Smeyers &
Willems 2001). As the star evolves on the main sequence, the deviations caused
by the compressibility of the stellar fluid increase with increasing radius of
the star. The additional deviations caused by the resonances are largest near
the end of the core-hydrogen burning phase. Both of these deviations increase
with increasing values of the orbital eccentricity.Comment: 7 pages, Accepted for publication in A&
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