Preserving memories on-line : the exhibition 'Memories of our childhood' and the Catalan Immigration History Museum

Gràcies a la introducció d'Internet, les institucions de la memòria poden anar ara un pas endavant i proporcionar narratives i documentació en línia. La present comunicació intenta descobrir com poden ser utilitzades les memòries en línia basant-se en dues experiències: una exposició de nens de la guerra i un portal d'immigració.

Imp2 controls oxidative phosphorylation and is crucial for preserving glioblastoma cancer stem cells.

Growth of numerous cancer types is believed to be driven by a subpopulation of poorly differentiated cells, often referred to as cancer stem cells (CSCs), that have the capacity for self-renewal, tumor initiation, and generation of nontumorigenic progeny. Despite their potentially key role in tumor establishment and maintenance, the energy requirements of these cells and the mechanisms that regulate their energy production are unknown. Here, we show that the oncofetal insulin-like growth factor 2 mRNA-binding protein 2 (IMP2, IGF2BP2) regulates oxidative phosphorylation (OXPHOS) in primary glioblastoma (GBM) sphere cultures (gliomaspheres), an established in vitro model for CSC expansion. We demonstrate that IMP2 binds several mRNAs that encode mitochondrial respiratory chain complex subunits and that it interacts with complex I (NADH:ubiquinone oxidoreductase) proteins. Depletion of IMP2 in gliomaspheres decreases their oxygen consumption rate and both complex I and complex IV activity that results in impaired clonogenicity in vitro and tumorigenicity in vivo. Importantly, inhibition of OXPHOS but not of glycolysis abolishes GBM cell clonogenicity. Our observations suggest that gliomaspheres depend on OXPHOS for their energy production and survival and that IMP2 expression provides a key mechanism to ensure OXPHOS maintenance by delivering respiratory chain subunit-encoding mRNAs to mitochondria and contributing to complex I and complex IV assembly.

Lentivirus-mediated Bcl-2 expression in betaTC-tet cells improves resistance to hypoxia and cytokine-induced apoptosis while preserving in vitro and in vivo control of insulin secretion.

betaTC-tet cells are conditionally immortalized pancreatic beta cells which can confer long-term correction of hyperglycemia when transplanted in syngeneic streptozocin diabetic mice. The use of these cells for control of type I diabetes in humans will require their encapsulation and transplantation in non-native sites where relative hypoxia and cytokines may threaten their survival. In this study we genetically engineered betaTC-tet cells with the anti-apoptotic gene Bcl-2 using new lentiviral vectors and showed that it protected this cell line against apoptosis induced by hypoxia, staurosporine and a mixture of cytokines (IL-1beta, IFN-gamma and TNF-alpha). We further demonstrated that Bcl-2 expression permitted growth at higher cell density and with shorter doubling time. Expression of Bcl-2, however, did not inter- fere either with the intrinsic mechanism of growth arrest present in the betaTC-tet cells or with their normal glucose dose-dependent insulin secretory activity. Furthermore, Bcl-2 expressing betaTC-tet cells retained their capacity to secrete insulin under mild hypoxia. Finally, transplantation of these cells under the kidney capsule of streptozocin diabetic C3H mice corrected hyperglycemia for several months. These results demonstrate that the murine betaTC-tet cell line can be genetically modified to improve its resistance against different stress-induced apoptosis while preserving its normal physiological function. These modified cells represent an improved source for cell transplantation therapy of type I diabetes.

On Parallel Communicating Grammar Systems and Correctness Preserving Restarting Automata

This paper contributes to the study of Freely Rewriting Restarting Automata (FRR-automata) and Parallel Communicating Grammar Systems (PCGS), which both are useful models in computational linguistics. For PCGSs we study two complexity measures called 'generation complexity' and 'distribution complexity', and we prove that a PCGS Pi, for which the generation complexity and the distribution complexity are both bounded by constants, can be transformed into a freely rewriting restarting automaton of a very restricted form. From this characterization it follows that the language L(Pi) generated by Pi is semi-linear, that its characteristic analysis is of polynomial size, and that this analysis can be computed in polynomial time.

A simple and rapid method for preserving RNA of aquatic invertebrates for ecotoxicogenomics

Here we describe a novel, inexpensive and simple method for preserving RNA that reduces handling stress in aquatic invertebrates following ecotoxicogenomic experimentation. The application of the method is based on transcriptomic experiments conducted on Daphnia magna, but may easily be applied on a range of other aquatic organisms of a particular size with e.g. amphipod Gammarus pulex representing an upper size limit. We explain in detail how to apply this new method, named the "Cylindrical Sieve (CS) system", and highlight its advantages and disadvantages.

The METAFOR project: preserving data through metadata standards for climate models and simulations

Climate modeling is a complex process, requiring accurate and complete metadata in order to identify, assess and use climate data stored in digital repositories. The preservation of such data is increasingly important given the development of ever-increasingly complex models to predict the effects of global climate change. The EU METAFOR project has developed a Common Information Model (CIM) to describe climate data and the models and modelling environments that produce this data. There is a wide degree of variability between different climate models and modelling groups. To accommodate this, the CIM has been designed to be highly generic and flexible, with extensibility built in. METAFOR describes the climate modelling process simply as "an activity undertaken using software on computers to produce data." This process has been described as separate UML packages (and, ultimately, XML schemas). This fairly generic structure canbe paired with more specific "controlled vocabularies" in order to restrict the range of valid CIM instances. The CIM will aid digital preservation of climate models as it will provide an accepted standard structure for the model metadata. Tools to write and manage CIM instances, and to allow convenient and powerful searches of CIM databases,. Are also under development. Community buy-in of the CIM has been achieved through a continual process of consultation with the climate modelling community, and through the METAFOR team’s development of a questionnaire that will be used to collect the metadata for the Intergovernmental Panel on Climate Change’s (IPCC) Coupled Model Intercomparison Project Phase 5 (CMIP5) model runs.

NIELSEN COINCIDENCE THEORY OF FIBRE-PRESERVING MAPS AND DOLD`S FIXED POINT INDEX

Let M -> B, N -> B be fibrations and f(1), f(2): M -> N be a pair of fibre-preserving maps. Using normal bordism techniques we define an invariant which is an obstruction to deforming the pair f(1), f(2) over B to a coincidence free pair of maps. In the special case where the two fibrations axe the same and one of the maps is the identity, a weak version of our omega-invariant turns out to equal Dold`s fixed point index of fibre-preserving maps. The concepts of Reidemeister classes and Nielsen coincidence classes over B are developed. As an illustration we compute e.g. the minimal number of coincidence components for all homotopy classes of maps between S(1)-bundles over S(1) as well as their Nielsen and Reidemeister numbers.

Tempol ameliorates murine viral encephalomyelitis by preserving the blood-brain barrier, reducing viral load, and lessening inflammation

Multiple sclerosis (MS) is a progressive inflammatory and/or demyelinating disease of the human central nervous system (CNS). Most of the knowledge about the pathogenesis of MS has been derived from murine models, such as experimental autoimmune encephalomyelitis and vital encephalomyelitis. Here, we infected female C57BL/6 mice with a neurotropic strain of the mouse hepatitis virus (MHV-59A) to evaluate whether treatment with the multifunctional antioxidant tempol (4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyloxy) affects the ensuing encephalomyelitis. In untreated animals, neurological symptoms developed quickly: 90% of infected mice died 10 days after virus inoculation and the few survivors presented neurological deficits. Treatment with tempol (24 mg/kg, ip, two doses on the first day and daily doses for 7 days plus 2 mM tempol in the drinking water ad libitum) profoundly altered the disease outcome: neurological symptoms were attenuated, mouse survival increased up to 70%, and half of the survivors behaved as normal mice. Not Surprisingly, tempol substantially preserved the integrity of the CNS, including the blood-brain barrier. Furthermore, treatment with tempol decreased CNS vital titers, macrophage and T lymphocyte infiltration, and levels of markers of inflammation, such as expression of inducible nitric oxide synthase, transcription of tumor necrosis factor-alpha and interferon-gamma, and protein nitration. The results indicate that tempol ameliorates murine viral encephalomyelitis by altering the redox status of the infectious environment that contributes to an attenuated CNS inflammatory response. overall, our study supports the development of therapeutic strategies based on nitroxides to manage neuroinflammatory diseases, including MS. (C) 2009 Elsevier Inc. All rights reserved.

Lorentz-violating dilatations in momentum space and some extensions on nonlinear actions of Lorentz-algebra-preserving systems

We work on some general extensions of the formalism for theories which preserve the relativity of inertial frames with a nonlinear action of the Lorentz transformations on momentum space. Relativistic particle models invariant under the corresponding deformed symmetries are presented with particular emphasis on deformed dilatation transformations. The algebraic transformations relating the deformed symmetries with the usual (undeformed) ones are provided in order to preserve the Lorentz algebra. Two distinct cases are considered: a deformed dilatation transformation with a spacelike preferred direction and a very special relativity embedding with a lightlike preferred direction. In both analysis we consider the possibility of introducing quantum deformations of the corresponding symmetries such that the spacetime coordinates can be reconstructed and the particular form of the real space-momentum commutator remains covariant. Eventually feasible experiments, for which the nonlinear Lorentz dilatation effects here pointed out may be detectable, are suggested.

Hopf solitons and area-preserving diffeomorphisms of the sphere

We consider a (3+1)-dimensional local field theory defined on the sphere S-2. The model possesses exact soliton solutions with nontrivial Hopf topological charges and an infinite number of local conserved currents. We show that the Poisson bracket algebra of the corresponding charges is isomorphic to that of the area-preserving diffeomorphisms of the sphere S-2. We also show that the conserved currents under consideration are the Noether currents associated to the invariance of the Lagrangian under that infinite group of diffeomorphisms. We indicate possible generalizations of the model.

The Noether theorem for geometric actions and area preserving diffeomorphisms on the torus

We find that within the formalism of coadjoint orbits of the infinite dimensional Lie group the Noether procedure leads, for a special class of transformations, to the constant of motion given by the fundamental group one-cocycle S. Use is made of the simplified formula giving the symplectic action in terms of S and the Maurer-Cartan one-form. The area preserving diffeomorphisms on the torus T2=S1⊗S1 constitute an algebra with central extension, given by the Floratos-Iliopoulos cocycle. We apply our general treatment based on the symplectic analysis of coadjoint orbits of Lie groups to write the symplectic action for this model and study its invariance. We find an interesting abelian symmetry structure of this non-linear problem.