El portafoli electrònic com a procediment avaluador de l'aprenentatge per a la comprensió als centres de secundària de la xarxa school+

[cat] El projecte que s'ha dut a terme sota el nom "El portafoli electrònic com a procediment avaluador de l'aprenentatge per a la comprensió als centres de secundària de la Xarxa School +", s'ha desenvolupat a partir de tres eixos prioritaris que sintetitzen els objectius que ens havíem plantejat:1. Desenvolupar una experiència pedagògica que impliqués la perspectiva educativa delsprojectes de treball, i la utilització del sistema d¿ensenyament i aprenentatge virtualSchool+Microcosmos. 2. Afavorir una experiència de col·laboració entre el professorat de cada centre i entre elprofessorat dels diferents centres participants. 3. Realitzar una recerca sistemàtica, a partir de la utilització de diferents procediments de recollida d'evidències (observacions, entrevistes, anàlisis de materials, actes de reunió delgrup, informes finals,...) al voltant de les formes de comprensió que es poden produir per part dels estudiants, i com a camí per un replantejament de l'aprenentatge a l'educació secundària. La recerca desenvolupada ens ha mostrat com les possibilitats de promoure la comprensió des de la perspectiva educativa adoptada -els projectes de treball- són manifestes, però es troben limitades per les constriccions organitzatives -sobretot temporals i espacials- i curriculars que actualmentmediatitzen la capacitat innovadora dels centres de secundària. Aquest informe recull els processos i els resultats de la recerca i la innovació educativa realitzades, així com algunes de les seves conseqüències per a plantejar canvis en l'educació secundària.

Measuring brain perfusion with intravoxel incoherent motion (IVIM): Initial clinical experience.

PURPOSE: To evaluate the feasibility of intravoxel incoherent motion (IVIM) perfusion measurements in the brain with currently available imaging systems. MATERIALS AND METHODS: We acquired high in-plane resolution (1.2 × 1.2 mm(2) ) diffusion-weighted images with 16 different values of b ranging from 0 to 900 s/mm(2) , in three orthogonal directions, on 3T systems with a 32-multichannel receiver head coil. IVIM perfusion maps were extracted by fitting a double exponential model of signal amplitude decay. Regions of interest were drawn in pathological and control regions, where IVIM perfusion parameters were compared to the corresponding dynamic susceptibility contrast (DSC) parameters. RESULTS: Hyperperfusion was found in the nonnecrotic or cystic part of two histologically proven glioblastoma multiforme and in two histologically proven glioma WHO grade III, as well as in a brain metastasis of lung adenocarcinoma, in a large meningioma, and in a case of ictal hyperperfusion. A monoexponential decay was found in a territory of acute ischemia, as well as in the necrotic part of a glioblastoma. The IVIM perfusion fraction f correlated well with DSC CBV. CONCLUSION: Our initial report suggests that high-resolution brain perfusion imaging is feasible with IVIM in the current clinical setting. J. Magn. Reson. Imaging 2014;39:624-632. © 2013 Wiley Periodicals, Inc.

Social network architecture and the maintenance of deleterious cultural traits.

How have changes in communications technology affected the way that misinformation spreads through a population and persists? To what extent do differences in the architecture of social networks affect the spread of misinformation, relative to the rates and rules by which individuals transmit or eliminate different pieces of information (cultural traits)? Here, we use analytical models and individual-based simulations to study how a 'cultural load' of misinformation can be maintained in a population under a balance between social transmission and selective elimination of cultural traits with low intrinsic value. While considerable research has explored how network architecture affects percolation processes, we find that the relative rates at which individuals transmit or eliminate traits can have much more profound impacts on the cultural load than differences in network architecture. In particular, the cultural load is insensitive to correlations between an individual's network degree and rate of elimination when these quantities vary among individuals. Taken together, these results suggest that changes in communications technology may have influenced cultural evolution more strongly through changes in the amount of information flow, rather than the details of who is connected to whom.

Light intensity modulates the regulatory network of the shade avoidance response in Arabidopsis.

Plants such as Arabidopsis thaliana respond to foliar shade and neighbors who may become competitors for light resources by elongation growth to secure access to unfiltered sunlight. Challenges faced during this shade avoidance response (SAR) are different under a light-absorbing canopy and during neighbor detection where light remains abundant. In both situations, elongation growth depends on auxin and transcription factors of the phytochrome interacting factor (PIF) class. Using a computational modeling approach to study the SAR regulatory network, we identify and experimentally validate a previously unidentified role for long hypocotyl in far red 1, a negative regulator of the PIFs. Moreover, we find that during neighbor detection, growth is promoted primarily by the production of auxin. In contrast, in true shade, the system operates with less auxin but with an increased sensitivity to the hormonal signal. Our data suggest that this latter signal is less robust, which may reflect a cost-to-robustness tradeoff, a system trait long recognized by engineers and forming the basis of information theory.