41 research outputs found
Why are migrant students better off in certain types of educational systems or schools than in others?
The main research question of this paper is the combined estimation of the effects of educational systems, school composition, track level, and country of origin on the educational achievement of 15-year-old migrant students. We focus specifically on the effects of socioeconomic and ethnic background on achievement scores and the extent to which these effects are affected by characteristics of the school, track, or educational system in which these students are enrolled. In doing so, we examine the ‘sorting’ mechanisms of schools and tracks in highly stratified, moderately stratified, and comprehensive education systems. We use data from the 2006 Programme for International Student Assessment (PISA) wave.
Compared with previous research in this area, the paper’s main contribution is that we explicitly include the tracks-within-school level as a separate unit of analyses, which leads to less biased results concerning the effects of educational system characteristics.
The results highlight the importance of including factors of track level and school composition in the debate surrounding educational inequality of opportunity for students in different education contexts. The findings clearly indicate that the effects of educational system characteristics are flawed if the analysis only uses a country- and a student level and ignores the tracks-within-school level characteristics. From a policy perspective, the most important finding is that educational systems are neither uniformly ‘good’ nor ‘bad’, but they can result in different consequences for different migrant groups. Some migrant groups are better off in comprehensive systems, while others are better off in moderately stratified systems
The effect of dietary zinc level and source on yearling bull growth and fertility
To study the effect of dietary zinc level and
source on bull growth and fertility, 325 yearling
Angus bulls were allotted by weight into six
pens (three pens of heavy and three pens of
lightweight bulls). The three supplemental zinc
(Zn) treatments were 1) 40 ppm inorganic Zn
all supplied by Zn sulfate (ZnI); 2) 40 ppm Zn
with 1/3 supplied by Zn proteinate and 2/3
supplied by Zn sulfate (ZnPI); and 3) 60 ppm
ZnI all supplied by Zn sulfate (ZnHi). Initial
and final liver biopsies (10 per pen) were
collected and analyzed for zinc concentration.
Individual weights and scrotal circumferences
also were recorded at the start and conclusion of
the trial. Bull s intended for public sale (n=167)
had their semen collected and evaluated for
motility and morphological abnormalities. Bulls
with percent normal sperm cell counts of less
than 70% or with motility scores less than fair
(motility scores = poor, fair, good, very good)
were considered classification deferred (CD).
Following 126 days of treatment, ZnHi bulls
had a greater (P=.058) percent change in liver
Zn concentration than ZnI, but similar increases
to ZnPI. No difference s in bull ADG or percent
change in scrotal circumference were detected.
ZnPI and ZnHi bulls had a higher (P<.05)
percent of normal sperm cells than ZnI bulls.
ZnPI and ZnHi treatments had fewer (P<.05)
CD bulls than ZnI. In all fertility measures
observed , bulls receiving the Zn proteinate/Zn
sulfate combination at 40 ppm had improved
semen quality when compared to bulls
supplemented with 40 ppm Zn sulfate
Parental choice and education policy
SIGLEAvailable from British Library Document Supply Centre-DSC:3120.2475(12) / BLDSC - British Library Document Supply CentreGBUnited Kingdo