Slapen = studeren: slaapkwaliteit en studieresultaten

Studenten die gemiddeld zeven uur per nacht slapen, scoren een stuk beter op hun examens dan collega’s die maar zes uur slapen, zo blijkt uit een studie van de Universiteit Gent. Tot in de vroege uurtjes blokken, is dus geen goed idee, schrijven de onderzoekers

Mister Sandman, Bring Me Good Marks! On the Relationship Between Sleep Quality and Academic Achievement

There is growing evidence that health factors affect tertiary education success in a causal way. This study assesses the effect of sleep quality on academic achievement at university. To this end, we surveyed 804 students about their sleep quality by means of the Pittsburgh Sleep Quality Index (PSQI) before the start of their first exam period in December 2013 at Ghent University. PSQI scores were merged with course marks in this exam period. Instrumenting PSQI scores by sleep quality during secondary education, we find that increasing total sleep quality with one standard deviation leads to 4.85 percentage point higher course marks. Based on this finding, we suggest that higher education providers might be incentivised to invest part of their resources for social facilities in professional support for students with sleep and other health problems.publisher: Elsevier articletitle: Mister Sandman, bring me good marks! On the relationship between sleep quality and academic achievement journaltitle: Social Science & Medicine articlelink: http://dx.doi.org/10.1016/j.socscimed.2015.02.011 content_type: article copyright: Copyright © 2015 Elsevier Ltd. All rights reserved.status: publishe

Tropical wood stores substantial amounts of nutrients, but we have limited understanding why

Rock-derived nutrients such as calcium (Ca), magnesium (Mg), phosphorus (P), and potassium (K) are essential plant resources, yet depleted in highly weathered tropical soils, leading to nutrient limitation of productivity or other ecosystem processes. Despite this, substantial amounts of rock-derived nutrients occur within wood, which raises questions about the role that wood nutrients play in the ecology of tropical forests. Using data from forests across the tropics, we quantify wood nutrient stocks at individual tree and ecosystem levels. At the ecosystem level, we show that tropical wood can store substantial amounts of rock-derived nutrients. Furthermore, on a tree level, tree species vary widely in woody nutrient concentrations. These observations raise important questions as to the biogeochemical or ecological drivers that lead to this variability, as well as the role that woody tissue plays in the buffering and cycling of nutrients. We offer some potential explanations and direction for future research to explore this under-appreciated but sizable store of inorganic nutrients in tropical biomass