Interdisciplinarietat a l'educació científica

La comunicació es proposa analitzar les relacions entre les diferents disciplines científiques presents al currículum d'educació secundària obligatòria. Intenta acostar-se a un model d'interdisciplinarietat, amb els aspectes comuns. Se centra en el desenvolupament d'una competència científica com és la resolució de problemes. S'estudien els diferents contextos reals en què es poden presentar les situacions problemàtiques pròpies de les diverses disciplines científiques. Les recreacions matemàtiques constitueixen una estratègia didàctica que afavoreix la interdisciplinarietat i transmet una forta motivació. Com a resultat, la competència assolida els permetrà prendre decisions conscients i raonades en el futur

Interdisciplinarietat a l’educació científica

La comunicació es proposa analitzar les relacions entre les diferents disciplines científiques presents al currículum d’educació secundària obligatòria. Intenta acostar-se a un model d’interdisciplinarietat, amb els aspectes comuns. Se centra en el desenvolupament d’una competència científica com és la resolució de problemes. S’estudien els diferents contextos reals en què es poden presentar les situacions problemàtiques pròpies de les diverses disciplines científiques. Les recreacions matemàtiques constitueixen una estratègia didàctica que afavoreix la interdisciplinarietat i transmet una forta motivació. Com a resultat, la competència assolida els permetrà prendre decisions conscients i raonades en el futur

Role of traditional healers in the management of severe malaria among children below five years of age: the case of Kilosa and Handeni Districts, Tanzania

BACKGROUND: The current malaria control strategy of WHO centres on early diagnosis and prompt treatment using effective drugs. Children with severe malaria are often brought late to health facilities and traditional health practitioners are said to be the main cause of treatment delay. In the context of the Rectal Artesunate Project in Tanzania, the role of traditional healers in the management of severe malaria in children was studied. METHODOLOGY: A community cross-sectional study was conducted in Kilosa and Handeni Districts, involving four villages selected on the basis of existing statistics on the number of traditional health practitioners involved in the management of severe malaria. A total of 41 traditional health practitioners were selected using the snowballing technique, whereby in-depth interviews were used to collect information. Eight Focus Group Discussions (FGDs) involving traditional health practitioners, caregivers and community leaders were carried out in each district. RESULTS: Home management of fever involving sponging or washing with warm water at the household level, was widely practiced by caregivers. One important finding was that traditional health practitioners and mothers were not linking the local illness termed degedege, a prominent feature in severe malaria, to biomedically-defined malaria. The majority of mothers (75%) considered degedege to be caused by evil spirits. The healing process was therefore organized in stages and failure to abide to the procedure could lead to relapse of degedege, which was believed to be caused by evil spirits. Treatment seeking was, therefore, a complex process and mothers would consult traditional health practitioners and modern health care providers, back and forth. Referrals to health facilities increased during the Rectal Artesunate Project, whereby project staff facilitated the process after traditional medical care with the provision of suppositories. This finding is challenging the common view that traditional healers are an important factor of delay for malaria treatment, they actually play a pivotal role by giving "bio-medically accepted first aid" which leads to reduction in body temperature hence increasing chances of survival for the child. Increasing the collaboration between traditional healers and modern health care providers was shown to improve the management of severe malaria in the studied areas. INTERPRETATION AND CONCLUSION: Traditional health care is not necessarily a significant impediment or a delaying factor in the treatment of severe malaria. There is a need to foster training on the management of severe cases, periodically involving both traditional health practitioners and health workers to identify modalities of better collaboration

Long-Term Continuous Corticosterone Treatment Decreases VEGF Receptor-2 Expression in Frontal Cortex

Objective: Stress and increased glucocorticoid levels are associated with many neuropsychiatric disorders including schizophrenia and depression. Recently, the role of vascular endothelial factor receptor-2 (VEGFR2/Flk1) signaling has been implicated in stress-mediated neuroplasticity. However, the mechanism of regulation of VEGF/Flk1 signaling under longterm continuous glucocorticoid exposure has not been elucidated. Material and Methods: We examined the possible effects of long-term continuous glucocorticoid exposure on VEGF/Flk1 signaling in cultured cortical neurons in vitro, mouse frontal cortex in vivo, and in post mortem human prefrontal cortex of both control and schizophrenia subjects. Results: We found that long-term continuous exposure to corticosterone (CORT, a natural glucocorticoid) reduced Flk1 protein levels both in vitro and in vivo. CORT treatment resulted in alterations in signaling molecules downstream to Flk1 such as PTEN, Akt and mTOR. We demonstrated that CORT-induced changes in Flk1 levels are mediated through glucocorticoid receptor (GR) and calcium. A significant reduction in Flk1-GR interaction was observed following CORT exposure. Interestingly, VEGF levels were increased in cortex, but decreased in serum following CORT treatment. Moreover, significant reductions in Flk1 and GR protein levels were found in postmortem prefrontal cortex samples from schizophrenia subjects. Conclusions: The alterations in VEGF/Flk1 signaling following long-term continuous CORT exposure represents a molecula

Emergent Functional Properties of Neuronal Networks with Controlled Topology

The interplay between anatomical connectivity and dynamics in neural networks plays a key role in the functional properties of the brain and in the associated connectivity changes induced by neural diseases. However, a detailed experimental investigation of this interplay at both cellular and population scales in the living brain is limited by accessibility. Alternatively, to investigate the basic operational principles with morphological, electrophysiological and computational methods, the activity emerging from large in vitro networks of primary neurons organized with imposed topologies can be studied. Here, we validated the use of a new bio-printing approach, which effectively maintains the topology of hippocampal cultures in vitro and investigated, by patch-clamp and MEA electrophysiology, the emerging functional properties of these grid-confined networks. In spite of differences in the organization of physical connectivity, our bio-patterned grid networks retained the key properties of synaptic transmission, short-term plasticity and overall network activity with respect to random networks. Interestingly, the imposed grid topology resulted in a reinforcement of functional connections along orthogonal directions, shorter connectivity links and a greatly increased spiking probability in response to focal stimulation. These results clearly demonstrate that reliable functional studies can nowadays be performed on large neuronal networks in the presence of sustained changes in the physical network connectivity

Recovery of mouse neuromuscular junctions from single and repeated injections of botulinum neurotoxin A

Botulinum neurotoxin type A (BoNT/A) paralyses muscles by blocking acetylcholine (ACh) release from motor nerve terminals. Although highly toxic, it is used clinically to weaken muscles whose contraction is undesirable, as in dystonias. The effects of an injection of BoNT/A wear off after 3–4 months so repeated injections are often used. Recovery of neuromuscular transmission is accompanied by the formation of motor axon sprouts, some of which form new synaptic contacts. However, the functional importance of these new contacts is unknown. Using intracellular and focal extracellular recording we show that in the mouse epitrochleoanconeus (ETA), quantal release from the region of the original neuromuscular junction (NMJ) can be detected as soon as from new synaptic contacts, and generally accounts for > 80% of total release. During recovery the synaptic delay and the rise and decay times of endplate potentials (EPPs) become prolonged approximately 3-fold, but return to normal after 2–3 months. When studied after 3–4 months, the response to repetitive stimulation at frequencies up to 100 Hz is normal. When two or three injections of BoNT/A are given at intervals of 3–4 months, quantal release returns to normal values more slowly than after a single injection (11 and 15 weeks to reach 50% of control values versus 6 weeks after a single injection). In addition, branching of the intramuscular muscular motor axons, the distribution of the NMJs and the structure of many individual NMJs remain abnormal. These findings highlight the plasticity of the mammalian NMJ but also suggest important limits to it

Contacts et acculturations en Méditerranée occidentale

La question des contacts entre les différents peuples qui bordent les rives de la Méditerranée nord occidentale est l’un des sujets phares de la recherche archéologique de ces trente dernières années. Que l’on parle d’époque archaïque et classique ou de Protohistoire et d’âge du Fer, les échanges et les processus d’acculturation de ces peuples qui entrèrent alors en contact les uns avec les autres : Grecs, Celtes, Phéniciens, Ibères, Ligures, Étrusques, ont retenu l’attention des chercheurs travaillant sur l’expansion grecque dans ces régions, sur les trafics commerciaux, sur les échanges culturels. L’œuvre de Michel Bats (Directeur de recherche honoraire du CNRS) traverse toutes ces thématiques : la présence des Phocéens et des Étrusques dans le bassin occidental de la Méditerranée, l’acculturation et les identités ethno-culturelles, les recherches sur la céramique et ses usages dans une perspective anthropologique, l’appropriation de l’écriture par les sociétés protohistoriques. Ses collègues et amis, en organisant ce colloque et en participant à ces actes, entendent lui témoigner leur amitié et leur dette intellectuelle. Ce volume réunit des articles des meilleurs spécialistes, actuels de la question - des chercheurs de toute la Méditerranée - autour des quatre grands thèmes que nous venons d’évoquer afin tout à la fois de dresser un bilan et de définir de nouvelles perspectives. Cet ouvrage présente donc aussi bien des synthèses - sur la présence grecque en Espagne, sur l’origine de l’écriture, sur les pratiques funéraires, sur les identités culturelles et ethniques - que des découvertes récentes concernant la thématique des contacts et de l’acculturation en Méditerranée nord occidentale : l’agglomération du Premier âge du Fer de La Cougourlude (Lattes, Hérault) fouillée durant l’été 2010 ; le sanctuaire hellénistique de Cumes et les fouilles récentes de Fratte en Italie ; les ateliers de potiers de Rosas en Espagne ; les dernières découvertes d’Olbia de Provence