Teachers as designers of GBL scenarios: Fostering creativity in the educational settings

This paper presents a research started in 2010 with the aim of fostering the creativity of teachers through the design of Game-Based Learning scenarios. The research has been carried out involving teachers and trainers in the co-design and implementation of digital games as educational resources. Based on the results grained from the research, this paper highlights successful factors of GBL, as well as constraints and boundaries that the introduction of innovative teaching and learning practices faces within educational settings

Phosphorescent perylene imides.

Asymmetrically substituted perylene imide derivatives PIa and PIx display phosphorescence in glassy matrices at 77 K. The lifetime is 49.0 ms for PIa and 13.5 ms for PIx. The triplet energy is 1.79 eV for PIa and 1.68 eV for PIx as confirmed by sensitization experiments of the C60 triplet

Self-organized partitioning of dynamically localized proteins in bacterial cell division

The Min proteins are equally partitioned between daughter cells at division.The mechanism allowing this accurate distribution is intrinsic to the Min system.Individual oscillations appear in each daughter cell before cytokinesis is completed.Diffusion through the gradually constricting septum is key to this process

Go in! Go out! Inducible control of nuclear localization

Cells have evolved a variety of mechanisms to regulate the enormous complexity of processes taking place inside them. One mechanism consists in tightly controlling the localization of macromolecules, keeping them away from their place of action until needed. Since a large fraction of the cellular response to external stimuli is mediated by gene expression, it is not surprising that transcriptional regulators are often subject to stimulus-induced nuclear import or export. Here we review recent methods in chemical biology and optogenetics for controlling the nuclear localization of proteins of interest inside living cells. These methods allow researchers to regulate protein activity with exquisite spatiotemporal control, and open up new possibilities for studying the roles of proteins in a broad array of cellular processes and biological functions

Considerations on the Glide Snow Avalanches based on the Stauchwall Model

Avalanches are natural events that can have consequences such as silvicultural losses, infrastructural damages, fatalities. In this paper, the attention is given to glide avalanches starting by a glide crack, a tensile crack that propagates at the crown – the upper release limit – due to the internal stress variation. However, the presence of a glide crack does not always give rise to a glide avalanche. In fact, when the slab starts to move, interacts with the stauchwall (the downslope boundary of the slab) which can fail or withstand.The Stauchwall model was adopted in order to verify if the gliding avalanche is triggered or not, by analyzing the dynamic stability of a slab subjected to an initial perturbation. In this paper, the model has been expanded by coupling it with a stress failure criterion. Thanks to this new failure criterion, it is possible to investigate the possible causes of subsequent glide avalanches triggering (in terms of hours or even days) after the crack propagation. In addition, the effect of a skier’s fall/brake on the slab stability is analyzed. Finally, a sensitivity analysis of the model pointed out the important role played by the basal snow/soil friction. Therefore, it is shown that actions meant to increase this characteristic may be taken into account to effectively prevent glide avalanche

Engineering a synthetic p53-Mdm2 network in budding yeast

p53 is among the most thoroughly studied proteins to date. Its tumour suppressor activity and the consideration that inactivation of the p53 pathway is a common, if not universal, feature of all human cancers, have gained it the interest of a multitude of researches seeking new therapies against this disease. As a consequence, p53 is at the centre of a feverish research and nowadays is reported to be involved in most cellular processes. Despite the vast amount of data published, much is yet to be unravelled about the mechanisms regulating the p53 signalling network. Indeed, the p53 network is extremely intricate and complex, and from a system biology point of view it can be seen as a series of interconnected negative and positive feedback loops, which can give rise to complex dynamics such as oscillations. In the combined effort to understand more of the biological meaning of these oscillations and to study the properties of this network motif from an engineering perspective, a synthetic p53 network has been built in budding yeast with the aim of studying the network in isolation while being embedded in living cells. p53 and most proteins in the network are absent from the budding yeast genome. This diminishes the likelihood of interferences on the engineered module from the cellular environment. Surprisingly, despite the evolutionary conservation of the ubiquitin pathway from yeast to humans, p53 ubiquitylation by the E3 ubiquitin ligase Mdm2 - an event central to the oscillatory dynamics of the system - does not appear to take place in budding yeast, even when the human E2 enzyme UbcH5B is exogenously expressed. p53 is instead sumoylated by Mdm2 and sumoylation dictates the co-localization of p53 and Mdm2 to a nuclear body reminiscent of human PML bodies. In conclusion, attempting to rebuild from scratch a simplified version of the intricate p53 network, isolating it from its natural context, has proven to be a very powerful means leading to unexpected findings, testifying the usefulness of the synthetic biology approach

Ultralong Organic Phosphorescence in the Solid State: The Case of Triphenylene Cocrystals with Halo- and Dihalo-penta/ tetrafluorobenzene

The polycyclic aromatic hydrocarbon (PAH) triphenylene (TP) has been reacted with halo-pentafluorobenzene (XF5, X = Br, I) and 1,4-dihalo-tetrafluorobenzene (X2F4, X = Br, I) to yield the corresponding cocrystals TP·BrF5, TP·Br2F4, TP·IF5, and TP·I2F4 form I. These materials have been synthesized by dissolving TP into an excess of liquid or molten coformer, and single crystals have been grown via seeding chloroform solutions. They have been fully characterized by a combination of techniques including X-ray diffraction, Raman spectroscopy, and luminescence spectroscopy in the solid state. TP·I2F4 form I was found to undergo a single-crystal to single-crystal (SCSC) polymorphic phase transition induced by temperature (when cooled down to 100 K) leading to the new form TP·I2F4 form II, which is transformed back into the first structure when brought again at RT. This behavior was confirmed also by Raman spectroscopy. Upon cocrystallization and as a result of the external heavy atom effect, all crystalline materials exhibited bright room temperature phosphorescence clearly visible by the naked eye. The latter was almost exclusive for cocrystal TP·I2F4, whereas for TP·Br2F4 both fluorescence and phosphorescence were detected. In TP·Br2F4, the phosphorescence lifetime was on the order of 200 ms, and with the visual outcome of an orange phosphorescence lasting for a couple of seconds upon ceasing the excitation, that makes this compound classifiable as an ultralong organic phosphorescent (UOP) material. The results evidenced the role of the nature of the heavy atom in governing the phosphorescence output from organic cocrystals

Estimating the dose-response function through the GLM approach

This paper revises the estimation of the dose-response function as in Hirano and Imbens (2004) by proposing a flexible way to estimate the generalized propensity score when the treatment variable is not necessarily normally distributed. We also provide a set of programs that accomplish this task by using the GLM in the first step of the computation

Estimating the dose-response function through the GLM approach

This paper revises the estimation of the dose-response function as in Hirano and Imbens (2004) by proposing a flexible way to estimate the generalized propensity score when the treatment variable is not necessarily normally distributed. We also provide a set of programs that accomplish this task by using the GLM in the first step of the computation