Rassenonderzoek witte asperge seizoen 2001-2002

In 2000 zijn twee nieuwe rassenproeven witte asperge aangelegd in Meterik, Nederland (PPO) en in Geel, België (PDLT). Er zijn 10 dezelfde rassen aangeplant op beide plaatsen. De rassen zijn gezaaid bij plantenkwekerij de Kemp in Meterik in 1999. Het sortiment bestaat uit de Hollandse rassen Backlim, Gijnlim, Thielim, Grolim afkomstig van Asparagus BV te Horst en de Duitse rassen Eposs, Ramada, Ramos, Ravel , Rally (96013) en Rapsody (96071) afkomstig van SWD Saatsucht. De Nederlandse rassen worden verkocht door Nunhem en de Duitse door Royal Sluis

The identification of reasons, solutions, and techniques informing a theory-based intervention targeting recreational sports participation

This study is the 3rd piece of formative research utilizing the theory of planned behavior to inform the development of a behavior change intervention. Focus groups were used to identify reasons for and solutions to previously identified key beliefs in addition to potentially effective behavior change techniques. A purposive sample of 22 first-year undergraduate students (n = 8 men; M  = 19.8 years, SD = 1.3 years) attending a university in the North of England was used. Focus groups were audio-recorded; recordings were transcribed verbatim, analyzed thematically, and coded for recurrent themes. The data revealed 14 reasons regarding enjoyment, 11 reasons for friends' approval, 11 reasons for friends' own participation, 14 reasons for the approval of family members, and 10 solutions to time constraints. Twelve distinct techniques were suggested to attend to these reasons and solutions. This qualitative research will be used to inform the development of a theory-based intervention to increase students' participation in university recreational sports

Polarization-dependent ponderomotive gradient force in a standing wave

The ponderomotive force is derived for a relativistic charged particle entering an electromagnetic standing wave with a general three-dimensional field distribution and a nonrelativistic intensity, using a perturbation expansion method. It is shown that the well-known ponderomotive gradient force expression does not hold for this situation. The modified expression is still of simple gradient form, but contains additional polarization-dependent terms. These terms arise because the relativistic translational velocity induces a quiver motion in the direction of the magnetic force, which is the direction of large field gradients. Oscillation of the Lorentz factor effectively doubles this magnetic contribution. The derived ponderomotive force generalizes the polarization-dependent electron motion in a standing wave obtained earlier [A.E. Kaplan and A.L. Pokrovsky, Phys. Rev. Lett. $\bm{95}$, 053601 (2005)]. Comparison with simulations in the case of a realistic, non-idealized, three-dimensional field configuration confirms the general validity of the analytical results.Comment: 13 pages, 4 figure

Stochastic Feedback and the Regulation of Biological Rhythms

We propose a general approach to the question of how biological rhythms spontaneously self-regulate, based on the concept of ``stochastic feedback''. We illustrate this approach by considering the neuroautonomic regulation of the heart rate. The model generates complex dynamics and successfully accounts for key characteristics of cardiac variability, including the $1/f$ power spectrum, the functional form and scaling of the distribution of variations, and correlations in the Fourier phases. Our results suggest that in healthy systems the control mechanisms operate to drive the system away from extreme values while not allowing it to settle down to a constant output.Comment: 15 pages, latex2e using rotate and epsf, with 4 ps figures. Submitted to PR

High-frequency AC breakdown in near-atmospheric pressure noble gasses

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Effect van folie bedekking op de opbrengst en kwaliteit van witte asperges en vergelijking oogstmachines 2000 - 2002

Het vaststellen en kwantificeren van de relaties tussen diverse folietoepassingen op de productie , kwaliteit en arbeidsbehoefte. Backlim reageert duidelijk positiever op de verschillende folie objecten dan Thielim. Opbrengst en de kwaliteit van de stengels alsmede de vroegheid zijn uitermate belangrijk in de uiteindelijke financiële opbrengst. Alhoewel Thielim vroeger is dan Backlim werd het voordeel te niet gedaan door een lagere opbrengst en slechtere kwaliteit

Poem to Dear Pastor Leraar

A brief poem is addressed to Dear Pastor (Leraar). There is no indication who the Pastor is, but the document is found in the Van Raalte Collection at Calvin College. Apparently the signers are students in a class which Rev. Albertus C. Van Raalte or someone close to the family taught. The names of the students are appended as well as the date. The students are: J. Wakker, J. Kroes, N. Kanters, A. Phanstiehl, L. Binnekant, R. Struik, G. Wakker, and K. Plugger, all familiar Holland names of that period.https://digitalcommons.hope.edu/vrp_1860s/1189/thumbnail.jp

Timing of antiretroviral therapy and adverse pregnancy outcomes : a systematic review and meta-analysis

BACKGROUND: Although life-long combination antiretroviral therapy (ART) is recommended for all HIV-infected individuals, there are limited data on pregnancy outcome with ART initiation pre-conception. We assessed the safety of ART initiated pre-conception versus post-conception on adverse pregnancy outcome. METHODS: We conducted a systematic review of studies from low-, middle-, and high-income countries. We searched Cochrane Central Register of Controlled Trials, EMBASE, LILACS, MEDLINE for randomized trials, quasi-randomized trials and prospective cohort studies conducted between 01 January 1980 to 01 June 2016). Risk ratios were pooled using a random-effects model. FINDINGS: Eleven studies were included (N=19,189 mother-infant pairs). Women initiating ART pre-conception compared to post-conception were significantly more likely to deliver preterm (pooled risk ratio[RR]=1·20, 95% confidence interval[CI] 1·01-1·14, 10 studies), very preterm (RR=1·53, 95%CI 1·22-1·92, two studies), or have low birth weight (LBW) infants (RR=1·30, 95%CI 1·04-1·62, two studies). Data on neonatal mortality was limited. We found no increase in very LBW (RR=0.18, 95% CI 0.02-1.51, one study), small for gestational age (SGA) (RR = 1·13, 95% CI 0·94-1·35, two studies), severe SGA (RR=1·09, 95%CI 0·82-1·45, one study), stillbirth (RR= RR=1·30, 95% CI 0·99-1·69, two studies) or congenital anomalies (RR= RR=1·24, 95% CI 0·61-2·49, one study). INTERPRETATION: The benefits of ART for maternal health and prevention of perinatal transmission outweigh risks, but there remain limited, poor quality data on the extent/severity of these risks. We found elevated preterm delivery and low birth weight rates associated with pre-conception ART. As pre-conception ART rapidly increases globally, it will be critical to monitor for potential adverse pregnancy outcomes