Aluminium (quels risques pour la santé)

STRASBOURG ILLKIRCH-Pharmacie (672182101) / SudocSudocFranceF

Effects of Divided Attention on Working and Long-Term Memory

An article that appeared in JASS, issue 2018In today’s classroom, students commonly watch videos, play games, or browse the internet while completing homework or participating in class. With the increasing use of technology in all aspects of our life, research into the effects of multitasking has increased in relevance. We aimed to evaluate whether distractions would impact working and long-term memory and to what extent. We hypothesized that visual and cognitive distraction would decrease the encoding of working memory and subsequent consolidation of long term memory directly and indirectly via inducing stress. Participants were assigned to one of two groups: a control group with no distractions or a treatment group exposed to a distraction. Both groups listened to a list of selected phrases and took a quiz at the end of the recording to evaluate their recognition of those phrases. This was done to assess the effects of distractions on working memory. Participants came back a week after their initial testing to assess their long-term memory with a similar quiz. Heart rate, respiration rate, and electrodermal activity were measured to evaluate stress. Results showed a difference in the week one quiz between the control and treatment group (p-value of 0.0002) and between quiz two of the control vs. treatment (p-value of 0.0002). These results suggest that students who use technology while studying or in class do significantly worse on multiple choice quizzes. All other physiological measures comparing treatment vs. control were not significant (p-value of 0.50, p-value of 0.71, and p-value of 0.36). Future studies can be enhanced by increasing the number of participants and investigating the effects of other sensory distractions on working and long-term memory

Three consecutive generations of nephridia occur during development of Platynereis dumerilii (Annelida, Polychaeta)

Molecular data for nephridial development in polychaetes are not available yet. The scope of our work was to establish a reference system for future investigations using two markers for nephridial development: beta-tubulin as marker for cilia and alkaline phosphatase (AP) activity for secretory epithelia. The markers identified, unexpectedly, three consecutively forming generations of nephridia: (1) a transitory unciliated, but AP-positive head kidney, (2) a transitory larval nephridium, which undergoes a morphological transition from a protonephridium to a funnelled nephridium concomitant with the development of the coelomic cavity and finally, (3) the serially arranged metanephridia. The spatial arrangement of larval and definitive nephridia, revealed an up to now unknown developmental boundary between the synchronously forming larval and the serially proliferating definitive segments. Development of three consecutive sets of nephridia with different morphology and biochemical properties was unexpected and reveals an interesting multistep process in the development of excretory structures in Platynereis