ZnO powders as multi-facet single crystals

Oxides are most commonly found in divided forms with properties difficult to control since their crystallographic orientations usually escape analysis. To overcome this an appropriate model system can be provided by ZnO smoke which, obtained by combustion of Zn in air, exhibits nanoparticles with well-defined surface facets. The present work focuses on the interaction of water with ZnO smokes by combining density functional theory based simulations and infrared spectroscopy measurements with applied pressures from 10(-7) to 1 mbar. We demonstrate that the use of ultra-high vacuum allows the analysis of the very first stages of the adsorption, and report on water structures on ZnO(11 (2) over bar0) for the first time. We further show that ZnO powders behave as multi-facet single crystals involving (10 (1) over bar 10), (11 (2) over bar0), (0001), and (000 (1) over bar) surfaces with the polar orientations corresponding to 25% of the total surface area. A great deal of cross-agreements between experimental results and simulation provides a simple approach for the examination of hydroxylated/hydrated ZnO smokes and can be widely applied on other ZnO-related powders

Information and Communication Technologies in Education as a Stimulus to Economic Development

Education has always been a driving force behind economic prosperity. However, this has become especially important in a globalized knowledge- and new-technology-based economy. The research presented in this paper focuses on the relationship between ICT, population education, and economic growth and development. The analysis of this relationship is based on the latest data collected from relevant national and international institutions. The results obtained from a survey conducted at the Faculty of Economics, University of Belgrade, are also analyzed. The paper highlights the challenges faced by the education systems in general, and the education system of the Republic of Serbia in particular, confronted with the new wave of technological innovation which is fundamentally changing the nature of work and imposing new requirements with regard to the necessary knowledge and skills. Our research results indicate that ICT and education have been recognized by the Government of the Republic of Serbia as the important determinants of economic and the overall social development

TGF-β uses a novel mode of receptor activation to phosphorylate SMAD1/5 and induce epithelial-to-mesenchymal transition

The best characterized signaling pathway downstream of transforming growth factor β (TGF-β) is through SMAD2 and SMAD3. However, TGF-β also induces phosphorylation of SMAD1 and SMAD5, but the mechanism of this phosphorylation and its functional relevance is not known. Here, we show that TGF-β-induced SMAD1/5 phosphorylation requires members of two classes of type I receptor, TGFBR1 and ACVR1, and establish a new paradigm for receptor activation where TGFBR1 phosphorylates and activates ACVR1, which phosphorylates SMAD1/5. We demonstrate the biological significance of this pathway by showing that approximately a quarter of the TGF-β-induced transcriptome depends on SMAD1/5 signaling, with major early transcriptional targets being the ID genes. Finally, we show that TGF-β-induced epithelial-to-mesenchymal transition requires signaling via both the SMAD3 and SMAD1/5 pathways, with SMAD1/5 signaling being essential to induce ID1. Therefore, combinatorial signaling via both SMAD pathways is essential for the full TGF-β-induced transcriptional program and physiological responses.publishe

Collective cell migration and metastases induced by an epithelial-to-mesenchymal transition in Drosophila intestinal tumors.

Metastasis underlies the majority of cancer-related deaths yet remains poorly understood due, in part, to the lack of models in vivo. Here we show that expression of the EMT master inducer Snail in primary adult Drosophila intestinal tumors leads to the dissemination of tumor cells and formation of macrometastases. Snail drives an EMT in tumor cells, which, although retaining some epithelial markers, subsequently break through the basal lamina of the midgut, undergo a collective migration and seed polyclonal metastases. While metastases re-epithelialize over time, we found that early metastases are remarkably mesenchymal, discarding the requirement for a mesenchymal-to-epithelial transition for early stages of metastatic growth. Our results demonstrate the formation of metastases in adult flies, and identify a key role for partial-EMTs in driving it. This model opens the door to investigate the basic mechanisms underlying metastasis, in a powerful in vivo system suited for rapid genetic and drug screens

Endothelial to Mesenchymal Transition in Cardiovascular Disease: Key Mechanisms and Clinical Translation Opportunities

Endothelial to mesenchymal transition (EndMT) is a process whereby an endothelial cell undergoes a series of molecular events that lead to a change in phenotype toward a mesenchymal cell (e.g., myofibroblast, smooth muscle cell). EndMT plays a fundamental role during development, and mounting evidence indicates that EndMT is involved in adult cardiovascular diseases (CVDs), including atherosclerosis, pulmonary hypertension, valvular disease, and fibroelastosis. Therefore, the targeting of EndMT may hold therapeutic promise for treating CVD. However, the field faces a number of challenges, including the lack of a precise functional and molecular definition, a lack of understanding of the causative pathological role of EndMT in CVDs (versus being a "bystander-phenomenon"), and a lack of robust human data corroborating the extent and causality of EndMT in adult CVDs. Here, we review this emerging but exciting field, and propose a framework for its systematic advancement at the molecular and translational levels. (J Am Coll Cardiol 2019; 73: 190-209) (c) 2019 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation

Sociomatematiska normer i två svenska och två finska algebraklassrum

Sammanfattning: Syftet med denna uppsats är att observera de sociomatematiska normer som råder i två svenska respektive två finska klassrum samt hur dessa skiljer sig från varandra. Uppsatsen söker även sprida medvetenhet om begreppet sociomatematiska normer och deras påverkan på undervisningen i matematikklassrummen. Vidare är uppsatsen ämnad att vara ett inlägg i den aktuella diskussionen om matematikundervisningen i Sverige gentemot den i Finland med anledning av resultatet i den senaste PISA- undersökningen (Skolverket, 013). Studien baseras på en kvalitativ analys av fyra videoinspelade algebralektioner i fyra olika klasser i årskurs 6 samt transkript från dessa lektioner. Två av klasserna är i Sverige och två av klasserna är i Finland. Forskningsmaterialet är hämtat ur projektet VIDEOMAT. Baserat på de sociomatematiska normer som med viss säkerhet kunnat identifieras i de fyra olika klassrummen under de observerade lektionerna görs en jämförelse där både de två ländernas klassrum och de fyra klassrummen vart och ett ställs mot varandra. Resultatet visar tydliga skillnader och likheter främst mellan de rådande sociomatematiska normerna i de två olika ländernas respektive klassrum. Där de två svenska klassrummen generellt präglas av ett relativt öppet och utforskande matematiskt klassrumsklimat och en synbar strävan från lärarnas sida att få matematiken att framstå som enkel och praktisk så präglas de två finska klassrummen snarare av mer avgränsade undervisningsmål dock med tydligare fokus på det aktuella matematiska begreppet och det givna tillvägagångssättet. Dessa skillnader mellan de sociomatematiska normerna i de två olika ländernas klassrum läggs till grund för en diskussion om möjliga konsekvenser av de olika undervisningssätten och en uppmaning till yrkesverksamma matematiklärare att granska och utmana de sociomatematiska normer som råder i deras egna klassrum.