Increasing MOOC completion rates through social interactions: a recommendation system

International audienceE-learning research shows students who interact with their peers are less likely to drop out from a course, but is this applicable to MOOCs? This paper examines MOOC attrition issues and how encouraging social interactions can address them: using data from 4 sessions of the GdP MOOC, a popular Project Management MOOC, we confirm that students displaying a high level of social interaction succeed more than those who don't. We successively explore two approaches fostering social interactions: 1) in MOOC GdP5, we give access to private group forums, testing various group types and sizes, 2) in MOOC GdP6, we implement a recommendation system, suggesting relevant chat contacts using demographic and progression criteria. This papers presents our preliminary findings

Does a Peer Recommender Foster Students' Engagement in MOOCs?

International audienceOverall the social capital of MOOCs is under-exploited. For most students in MOOCs, autonomous learning often means learning alone. Students interested in adding a social dimension to their learning can browse discussion threads, join social medias and may decide to message other students… but usually in a random way. This common isolation might be a contributing factor on student attrition rate and on their general learning experience. To foster learners' persistence in MOOCs, we propose to enhance the MOOC experience with a recommender which provides each student with an individual list of rich-potential contacts, created in real-time on the basis of their own profile and activities. This paper describes a controlled study conducted from Sept. to Nov. 2015 during a MOOC on Project Management. A recommender panel was integrated to the users' interface and allowed to manage contacts, send them an instant message or consult their profile. The population (N = 8,673) was randomly split into 2 parts: a control group, without any recommendations, and an experimental group in which students could choose to activate and use the recommender. After having demonstrated that these populations were similar up to the activation of the recommender, we evaluate the effect of the recommender on the basis of four pillars of learners' persistence: attendance, completion, success and participation. Results suggest that the recommender improved all these four factors: students were much more likely to persist and engage in the MOOC if they received recommendations than if they did not

Lability of IgE Levels Early in Life

We report a case of a very fast and intriguing decrease in IgE concentrations after exclusion from the diet of any CM lysate in an unusual clinical presentation of cow's milk allergy in an infant. Analysis of IgE kinetics after allergen elimination suggests rapid cessation of IgE biosynthesis and a short IgE half-life

Ocean acidification reshapes the otolith-body allometry of growth in juvenile seabream

International audienceThe effects of elevated CO2 partial pressure (pCO2) on otolith calcification and on the coupling between the somatic and otolith growth were investigated in juvenile gilthead seabream Sparus aurata. Six-month old individuals were raised during seven weeks under four pCO2 conditions set according to projected future ocean acidification scenarios. Body and otolith biometric parameters were measured throughout the experiment along with the otolith biomineralization monitored using a radiotracer technique based on 45Ca incorporation. Seabream exhibited somatic growth resilience to all treatments. In contrast, increased growth rate and shape complexity of otoliths were observed with a pHT drop from 8.1 to 7.5. Hypercalcification was observed under lowered pH, with a rate of calcium incorporation increasing by up to 18% between pHT 8.1 and pHT 7.7. This work highlighted an uncoupling of otolith and body growth of juvenile seabream within 40 d at pHT 7.9 projected to be reached by the end of the century. As the otolith is an essential tool used in reconstructing fish life history, this work suggests that information resulting from otolith studies should be interpreted with caution with respect to the potential impacts that ocean acidification projected modifications could have on otolith biomineralization

Randomized Controlled Trial of Parent Therapeutic Education on Antibiotics to Improve Parent Satisfaction and Attitudes in a Pediatric Emergency Department

Objective: To evaluate therapeutic education delivered in a pediatric emergency department to improve parents’ satisfaction and attitudes about judicious antibiotic use. Methods: In an emergency department of a tertiary pediatric hospital, children aged 1 month to 6 years and discharged with an oral antibiotic prescription for an acute respiratory or urinary tract infection were randomized to a patient therapeutic education on antibiotic use (intervention group) or fever control (control group) delivered to the parents (in the presence of the children) by a pharmacist trained in therapeutic education. Education consisted in a 30-minute face-to-face session with four components: educational diagnosis, educational contract, education, and evaluation. The main outcome measure was parent satisfaction about information on antibiotics received at the hospital, as assessed by a telephone interview on day 14. The secondary outcome was attitudes about antibiotic use evaluated on day 14 and at month 6. Results: Of the 300 randomized children, 150 per arm, 259 were evaluated on day 14. Parent satisfaction with information on antibiotics was higher in the intervention group (125/129, 96.9%, versus 108/130, 83.0%; P=0.002, exact Fisher test). Intervention Group parents had higher proportions of correct answers on day 14 to questions on attitudes about judicious antibiotic use than did control-group parents (P=0.017, Mann-Whitney U test). Conclusion: Therapeutic education delivered by a clinical pharmacist in the pediatric emergency department holds promise for improving the use of antibiotics prescribed to pediatric outpatients. Trial Registration ClinicalTrials.gov NCT00948779 http://clinicaltrials.gov/show/NCT0094877

Ocean acidification and temperature rise: effects on calcification during early development of the cuttlefish Sepia officinalis

This study investigated the effects of seawater pH (i.e., 8.10, 7.85 and 7.60) and temperature (16 and 19 °C) on (a) the abiotic conditions in the fluid surrounding the embryo (viz. the perivitelline fluid), (b) growth, development and (c) cuttlebone calcification of embryonic and juvenile stages of the cephalopod Sepia officinalis. Egg swelling increased in response to acidification or warming, leading to an increase in egg surface while the interactive effects suggested a limited plasticity of the swelling modulation. Embryos experienced elevated pCO2 conditions in the perivitelline fluid (>3-fold higher pCO2 than that of ambient seawater), rendering the medium under-saturated even under ambient conditions. The growth of both embryos and juveniles was unaffected by pH, whereas 45Ca incorporation in cuttlebone increased significantly with decreasing pH at both temperatures. This phenomenon of hypercalcification is limited to only a number of animals but does not guarantee functional performance and calls for better mechanistic understanding of calcification processes

Mitochondrial mosaics in the liver of 3 infants with mtDNA defects

<p>Abstract</p> <p>Background</p> <p>In muscle cytochrome oxidase (COX) negative fibers (mitochondrial mosaics) have often been visualized.</p> <p>Methods</p> <p>COX activity staining of liver for light and electron microscopy, muscle stains, blue native gel electrophoresis and activity assays of respiratory chain proteins, their immunolocalisation, mitochondrial and nuclear DNA analysis.</p> <p>Results</p> <p>Three unrelated infants showed a mitochondrial mosaic in the liver after staining for COX activity, i.e. hepatocytes with strongly reactive mitochondria were found adjacent to cells with many negative, or barely reactive, mitochondria. Deficiency was most severe in the patient diagnosed with Pearson syndrome. Ragged-red fibers were absent in muscle biopsies of all patients. Enzyme biochemistry was not diagnostic in muscle, fibroblasts and lymphocytes. Blue native gel electrophoresis of liver tissue, but not of muscle, demonstrated a decreased activity of complex IV; in both muscle and liver subcomplexes of complex V were seen. Immunocytochemistry of complex IV confirmed the mosaic pattern in two livers, but not in fibroblasts. MRI of the brain revealed severe white matter cavitation in the Pearson case, but only slight cortical atrophy in the Alpers-Huttenlocher patient, and a normal image in the 3rd. MtDNA in leucocytes showed a common deletion in 50% of the mtDNA molecules of the Pearson patient. In the patient diagnosed with Alpers-Huttenlocher syndrome, mtDNA was depleted for 60% in muscle. In the 3rd patient muscular and hepatic mtDNA was depleted for more than 70%. Mutations in the nuclear encoded gene of <it>POLG </it>were subsequently found in both the 2nd and 3rd patients.</p> <p>Conclusion</p> <p>Histoenzymatic COX staining of a liver biopsy is fast and yields crucial data about the pathogenesis; it indicates whether mtDNA should be assayed. Each time a mitochondrial disorder is suspected and muscle data are non-diagnostic, a liver biopsy should be recommended. Mosaics are probably more frequent than observed until now. A novel pathogenic mutation in <it>POLG </it>is reported.</p> <p>Tentative explanations for the mitochondrial mosaics are, in one patient, unequal partition of mutated mitochondria during mitoses, and in two others, an interaction between products of several genes required for mtDNA maintenance.</p

Altérations du métabolisme des acides gras dans l'hyperthrophie et l'insuffisance cardiaque (conséquences et évaluation)

L hypertrophie et l insuffisance cardiaque (IC) s accompagnent de perturbations du métabolisme énergétique. Des cœurs hypertrophiques de rats SHR ont été perfusés au travail avec divers acides gras (AG), puis soumis à une épreuve de stress adrénergique. Nos résultats suggèrent l existence d un niveau minimum critique d utilisation des AG exogènes à respecter pour maintenir des fonctions cardiaques optimales et soulignent l intérêt potentiel des AG à chaîne moyenne dans les situations d utilisation restreinte des AG à chaîne longue. Les altérations du métabolisme des AG ont été ensuite étudiées par le profil des acylcarnitines sanguins chez des patients atteints d IC. Les résultats démontrent une augmentation globale de la carnitine et ses dérivés circulants chez ces patients et suggèrent de multiples sites de perturbations du métabolisme énergétique. L ensemble de ces résultats souligne l importance de la contribution énergétique des AG pour la fonction cardiaque dans le cœur malade.Left ventricular hypertrophy and heart failure (HF) are associated with cardiac energy metabolism alterations. Hypertrophied SHR hearts have been perfused in a working mode with different fatty acid (FA) concentrations and subjected to an adrenergic stimulation. Results suggest that a critical threshold of exogenous FA contribution should be preserved for optimal cardiac functions and highlight the potential beneficial effect of a medium-chain FA administration in situations of reduced long-chain FA contribution. The consequences of FA metabolism alterations have been studied in HF patients, using blood acylcarnitine profiles. Results demonstrate a global increase in circulating carnitine and its derivatives in HF patients, suggesting multiple perturbation sites of energy metabolism. Collectively, results from these studies highligth the impact of FA contribution to energy production for cardiac functions of the diseased heart.TOURS-BU Médecine (372612103) / SudocPARIS-BIUP (751062107) / SudocSudocFranceF