Exploring the meanings of community multimedia centers in Mozambique: a social representation perspective

This article presents extensive research conducted in Mozambique that aims to deeply understand how different social groups understand community multimedia centers (CMCs), which are structures combining a community radio and a telecenter. The social representations theory was adopted to interpret narratives of 231 interviewees from 10 Mozambican provinces. Interviewees included representatives of initiating agencies, local staff members, CMC users (both the radio and telecenter components), users of only the community radio, and community members not using the CMCs. Following the analysis of transcribed interviews, six main clusters were identified, each of them shedding light on a specific understanding of a CMC. These are discussed according to a set of sociodemographic variables. This study suggests that the social representations theory is a valuable framework to provide an integrated view of ICT4D interventions by giving a voice to local perspectives without overlooking the initiating agencies' expectations

Exploring the meanings of community multimedia centers in Mozambique : a social representations perspective

This article presents extensive research conducted in Mozambique that aims to deeply understand how different social groups understand community multimedia centers (CMCs), which are structures combining a community radio and a telecenter. The social representations theory was adopted to interpret narratives of 231 interviewees from 10 Mozambican provinces. Interviewees included representatives of initiating agencies, local staff members, CMC users (both the radio and telecenter components), users of only the community radio, and community members not using the CMCs. Following the analysis of transcribed interviews, six main clusters were identified, each of them shedding light on a specific understanding of a CMC. These are discussed according to a set of sociodemographic variables. This study suggests that the social representations theory is a valuable framework to provide an integrated view of ICT4D interventions by giving a voice to local perspectives without overlooking the initiating agencies’ expectations

Efficiency of transient transformation in tobacco protoplasts is independent of plasmid amount

An optimized protocol for the transient transformation of tobacco protoplasts mediated by polyethylene\u2013glycol (PEG) is here described. As expected, the quantitative b\u2013glucuronidase (Gus) activity driven by pCaMVGus was dependent on the amount of plasmid used. Nevertheless, we demonstrate by an immunodetection method that transformation efficiency did not depend on the amount of plasmid used but on the limitation imposed by cell competence. In fact, we obtained the same percentage of transformed cells (about 60%) using a wide range of plasmid concentrations (0.1\u201310 mg per test). Finally, we show that, when we used two plasmid types in a mixture at a concentration ranging from 0.1 to 10 mg for each, all transformed cells expressed proteins encoded by both plasmids. Transient expression and co-transformation experiments are routinely used methods and, probably, the major results from this work were assumed by many researchers in this field, but our data experimentally support this assumption

Recontinentalizing Canada : Arctic ice’s liquid modernity and the imagining of a Canadian archipelago

Studying mobile actor networks of moving people, objects, images, and discourses, in conjunction with changing time-spaces, offers a unique opportunity to understand important, and yet relatively neglected, “relational material” dynamics of mobility. A key example of this phenomenon is the recontinentalization of Canada amidst dramatically changing articulations of the meanings and boundaries of the Canadian landice- ocean mass. A notable reason why Canada is being re-articulated in current times is the extensiveness of Arctic thawing. The reconfiguration of space and “motility” options in the Arctic constitutes an example of how “materiality and sociality produce themselves together.” In this paper we examine the possibilities and risks connected to this recontinentalization of Canada’s North. In exploring the past, present, and immediate future of this setting, we advance the paradigmatic view that Canada’s changing Arctic is the key element in a process of transformation of Canada into a peninsular body encompassed within a larger archipelagic entity: a place more intimately attuned to its immense (and growing) coastal and insular routes.peer-reviewe

Electrophysiology of glioma: a Rho GTPase-activating protein reduces tumor growth and spares neuron structure and function

Background. Glioblastomas are the most aggressive type of brain tumor. A successful treatment should aim at halting tumor growth and protecting neuronal cells to prevent functional deficits and cognitive deterioration. Here, we exploited a Rho GTPase-activating bacterial protein toxin, cytotoxic necrotizing factor 1 (CNF1), to interfere with glioma cell growth in vitro and vivo. We also investigated whether this toxin spares neuron structure and function in peritumoral areas. Methods. We performed a microarray transcriptomic and in-depth proteomic analysis to characterize the molecular changes triggered by CNF1 in glioma cells. We also examined tumor cell senescence and growth in vehicle-and CNF1-treated glioma-bearing mice. Electrophysiological and morphological techniques were used to investigate neuronal alterations in peritumoral cortical areas. Results. Administration of CNF1 triggered molecular and morphological hallmarks of senescence in mouse and human glioma cells in vitro. CNF1 treatment in vivo induced glioma cell senescence and potently reduced tumor volumes. In peritumoral areas of glioma-bearing mice, neurons showed a shrunken dendritic arbor and severe functional alterations such as increased spontaneous activity and reduced visual responsiveness. CNF1 treatment enhanced dendritic length and improved several physiological properties of pyramidal neurons, demonstrating functional preservation of the cortical network. Conclusions. Our findings demonstrate that CNF1 reduces glioma volume while at the same time maintaining the physiological and structural properties of peritumoral neurons. These data indicate a promising strategy for the development of more effective antiglioma therapies

Morphological and proteomic responses of Eruca sativa exposed to silver nanoparticles or silver nitrate

Silver nanoparticles (AgNPs) are widely used in commercial products, and there are growing concerns about their impact on the environment. Information about the molecular interaction of AgNPs with plants is lacking. To increase our understanding of the mechanisms involved in plant responses to AgNPs and to differentiate between particle specific and ionic silver effects we determined the morphological and proteomic changes induced in Eruca sativa (commonly called rocket) in response to AgNPs or AgNO3. Seedlings were treated for 5 days with different concentrations of AgNPs or AgNO3. A similar increase in root elongation was observed when seedlings were exposed to 10 mg Ag L-1 of either PVP-AgNPs or AgNO3. At this concentration we performed electron microscopy investigations and 2-dimensional electrophoresis (2DE) proteomic profiling. The low level of overlap of differentially expressed proteins indicates that AgNPs and AgNO3 cause different plant responses. Both Ag treatments cause changes in proteins involved in the redox regulation and in the sulfur metabolism. These responses could play an important role to maintain cellular homeostasis. Only the AgNP exposure cause the alteration of some proteins related to the endoplasmic reticulum and vacuole indicating these two organelles as targets of the AgNPs action. These data add further evidences that the effects of AgNPs are not simply due to the release of Ag ions

Linker histone H1.8 inhibits chromatin binding of condensins and DNA topoisomerase II to tune chromosome length and individualization

DNA loop extrusion by condensins and decatenation by DNA topoisomerase II (topo II) are thought to drive mitotic chromosome compaction and individualization. Here, we reveal that the linker histone H1.8 antagonizes condensins and topo II to shape mitotic chromosome organization. In vitro chromatin reconstitution experiments demonstrate that H1.8 inhibits binding of condensins and topo II to nucleosome arrays. Accordingly, H1.8 depletion in Xenopus egg extracts increased condensins and topo II levels on mitotic chromatin. Chromosome morphology and Hi-C analyses suggest that H1.8 depletion makes chromosomes thinner and longer through shortening the average loop size and reducing the DNA amount in each layer of mitotic loops. Furthermore, excess loading of condensins and topo II to chromosomes by H1.8 depletion causes hyper-chromosome individualization and dispersion. We propose that condensins and topo II are essential for chromosome individualization, but their functions are tuned by the linker histone to keep chromosomes together until anaphase

Overexpression of Osmyb4 enhances compatible solute accumulation and increases stress tolerance of arabidopsis thaliana

In this paper, we report the metabolic and molecular changes in response to cold and drought induced in Osmyb4 transgenic Arabidopsis thaliana compared with the wildtype (WT). The rice Osmyb4 gene codes for a transcription factor (Myb4) induced by cold treatment and, in Arabidopsis transgenic plants, improves cold and freezing tolerance [Vannini C, Locatelli F, Bracale M, Magnani E, Marsoni M, Osnato M, Mattana M, Baldoni E, Coraggio I (2004) Plant J 37: 115-127]. Here, we report the ability of Myb4 to induce also drought tolerance in Arabidopsis transgenic plants. By the use of nuclear magnetic resonance (NMR) and enzymatic assays, we showed that several compatible solutes (glucose, fructose, sucrose, proline, glycine betaine and sinapoyl malate) accumulate in higher amount in Osmyb4-overexpressing plants with respect to the WT, both under normal and stress conditions. Considering proline, we also found that in transgenic plants the levels of the mRNAs coding for \u3941- pyrroline-5-carboxylate synthase (EC not assigned) and for \u3941- pyrroline-5-carboxylate dehydrogenase (EC 1.5.1.12) were higher and lower, respectively. The constitutive activation of several stress-inducible pathways and different kinetics in the accumulation of several metabolites, in Myb4 transgenic plants, may represent an advantage to prepare plants to face the stress condition. Moreover, these results taken together suggest that Myb4 integrates the activation of multiple components of stress response