Disorder and fluctuations in nonlinear excitations in DNA

We study the effects of the sequence on the propagation of nonlinear excitations in simple models of DNA, and how those effects are modified by noise. Starting from previous results on soliton dynamics on lattices defined by aperiodic potentials, [F. Dom\'\i nguez-Adame {\em et al.}, Phys. Rev. E {\bf 52}, 2183 (1995)], we analyze the behavior of lattices built from real DNA sequences obtained from human genome data. We confirm the existence of threshold forces, already found in Fibonacci sequences, and of stop positions highly dependent on the specific sequence. Another relevant conclusion is that the effective potential, a collective coordinate formalism introduced by Salerno and Kivshar [Phys. Lett. A {\bf 193}, 263 (1994)] is a useful tool to identify key regions that control the behaviour of a larger sequence. We then study how the fluctuations can assist the propagation process by helping the excitations to escape the stop positions. Our conclusions point out to improvements of the model which look promising to describe mechanical denaturation of DNA. Finally, we also consider how randomly distributed energy focus on the chain as a function of the sequence.Comment: 14 pages, final version, accepted in Fluctuation and Noise Letters, scheduled to apper in vol. 4, issue 3 (2004

PLLA/ZnO nanocomposites: dynamic surfaces to harness cell differentiation

This work investigates the effect of the sequential availability of ZnO nanoparticles, (nanorods of ∼40 nm) loaded within a degradable poly(lactic acid) (PLLA) matrix, in cell differentiation. The system constitutes a dynamic surface, in which nanoparticles are exposed as the polymer matrix degrades. ZnO nanoparticles were loaded into PLLA and the system was measured at different time points to characterise the time evolution of the physicochemical properties, including wettability and thermal properties. The micro and nanostructure were also investigated using AFM, SEM and TEM images. Cellular experiments with C2C12 myoblasts show that cell differentiation was significantly enhanced on ZnO nanoparticles—loaded PLLA, as the polymer degrades and the availability of nanoparticles become more apparent, whereas the release of zinc within the culture medium was negligible. Our results suggest PLLA/ZnO nanocomposites can be used as a dynamic system where nanoparticles are exposed during degradation, activating the material surface and driving cell differentiation

Smallanthus sonchifolius (Yacon) leaves: an emerging source of compounds for diabetes management

Diabetes mellitus is a chronic metabolic disease that develops mainly due to insulin deficiency or resistance to insulin action. All forms of diabetes are characterized by chronic hyperglycemia, which has an important role in the pathogenesis of diabetic complications. Leaves of Smallanthus sonchifolius (Poepp.&Endl.) H. Robinson (yacon) have been used since ancient times to prepare medicinal herbal tea with beneficial health properties. This review aims to discuss some key aspects related to the potential use of S. sonchifolius leaves and their natural biomolecules for the prophylaxis and treatment of diabetes as well as the potential mechanisms of action.Fil: Honore, Stella Maris. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Genta, Susana Beatriz de Fátima. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Sanchez, Sara Serafina del V.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentin

Student mobility in tertiary education: institutional factors and regional attractiveness

Member States have committed themselves to promoting the learning mobility of young people following the 2011 Communication on an agenda for the modernisation of Europe’s higher education system (COM(2011) 567). The Council conclusions on a benchmark for learning mobility (2011/C 372/08) specified that by 2020 ‘an EU average of at least 20% of higher education graduates should have had a period of higher education-related study or training abroad’. In this report, two types of mobility are distinguished, namely degree mobility and credit mobility, both of which are included in the benchmark. Little research has been carried out on international student mobility determinants in general and on Erasmus students in particular, especially taking into account the regional dimension of learning mobility. This report focuses on student mobility in the EU between 2011 and 2014, through the description of the main destinations of mobile students, as well as on inward mobility across and within countries (measured as the share of mobile students on total student population), with a particular focus on institutions and regions. It also analyses the main factors associated with degree and credit mobility, taking into account different tertiary education levels (i.e. undergraduate, master and PhD level), through the comparison between institutional factors (teaching and research activities of universities as well as their reputation) and regional attractiveness (level of urbanisation, employment opportunities and regional education systems). There are five main conclusions from this report. First, in relation to the most attractive destinations, degree mobility appears to be very concentrated in a few countries, while credit mobility tends to be more equally distributed across Member States. Second, degree mobility is higher than credit mobility across and within countries. Third, institutional characteristics tend to be associated with student mobility more than regional ones. Fourth, among institutional characteristics, better quality universities and those with a higher reputation are associated with a higher share of mobile students, while research orientation and excellence are more relevant for degree mobile PhD students. Fifth, among regional characteristics, the level of urbanisation of the region is an important factor in shaping students’ mobility: high-density regions have higher degree mobility rates, but a lower share of credit mobile students.JRC.B.4-Human Capital and Employmen

Extracellular matrix remodeling and TGF-β1/Smad signaling in diabetic colon mucosa

Diabetes is associated with metabolic and functional alterations in the gut. Using an experimental model of streptozotocin (STZ)-induced diabetes in rodents, we analyzed the extracellular matrix (ECM) and TGF-β/Smad signaling in the colon mucosa. Male rats were divided into normal control, diabetic and insulin treated diabetic groups during 4 and 9 weeks. Sirius red staining showed marked increase in the extracellular matrix deposition in diabetic mucosa. High levels of fibrillar collagen (I and III) and fibronectin mRNAs were also detected with an imbalance between MMPs/TIMPs activities. Moreover, an increased mesenchymal cell proliferation together with an enhanced expression of myofibroblasts markers vimentin and α-SMA were observed. TGF-β/Smad signaling-related genes were determined using RT-PCR, Western blotting, and immunohistochemistry. Diabetic rats showed a significant up-regulation of TGF-β1, TGF-β receptors and the effectors p-Smad2/3 in the mucosa compared with control rats. Insulin treatment attenuated the stimulating effect of diabetes on colon ECM deposition and TGF-β/Smad signaling. In conclusion, the overall results showed a deregulation of the TGFβ1 pathway associated with the appearance of myofibroblasts and the accumulation of ECM in the mucosa of diabetic colon. These data provide the first in vivo evidence that TGF-β1/Smad is a key component of intestinal tissue remodeling in diabetes.Fil: D'arpino, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Fuchs, Alicia Graciela. Universidad Abierta Interamericana. Facultad de Medicina. Centro de Altos Estudios en Ciencias de la Salud; ArgentinaFil: Sanchez, Sara Serafina del V.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Honore, Stella Maris. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentin

Teens and Texts: Exploring the Literary Practices of Church-Going Teens

The purpose of this Phase 1 study was to explore adolescents’ faith-related literacy practices and thus build on a growing field of research on adolescents’ religious experiences (Smith and Denton, 2003; Dean, 2010). To collect data, we designed an online survey consisting of both qualitative and quantitative questions. The 37 participants, two-thirds of them female, were recruited from youth groups in and around a small midwestern town. 91% of the respondents reported that they attended youth group on a weekly basis. As a whole, we discovered that most adolescents seem to identify more with the relational aspect of their faith than they do with traditional religious literacy practices such as reading a Bible and devotionals on a regular basis. Faith-related literacy practices, for the teens we surveyed, seemed to be mostly social in purpose, function, and motivation

Chlorogenic acid: A promising natural agent for non-alcoholic fatty liver disease management

Emerging and relatively consistent evidence shows that chlorogenic acid (CGA), a phenolic acid, positively modulates a variety of contributors to the non-alcoholic fatty liver (NAFLD) phenotype, through diverse and complementary mechanisms of action. Therefore, we believe that CGA is a good candidate for the management of NAFLD that deserves a review to aid future research.Fil: Honore, Stella Maris. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Sanchez, Sara Serafina del V.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentin

Early and late stages of Developmental Biology in Argentina

The history of science in Argentina is based on the enormous contribution that the great immigration of the 19th and 20th centuries produced in the country. The scientific and philosophical ideas and the role played especially by Italian scientists who arrived in the country produced a great impact on the different disciplines including Development Biology in emerging universities. The University of Tucumán pioneered the study of experimental biology, making important contributions to reproductive biology and to the early development of amphibians. The contribution of the Italian embryologist Armando Pisanó and the Argentinian Francisco D. Barbieri expanded the field to other universities and research centers located in Córdoba, La Plata, Bahía Blanca and Rosario. Given its strategic position, laboratories located in the city of Buenos Aires reached technological advances faster than others. Indeed, these laboratories saw the evolution from experimental biology to developmental genetics, renewing interest in this area. Currently, Developmental Biology brings together young researchers eager to consolidate regional and global collaboration networks that seek to help solve specific problems such as fertility, epigenetics, stem cells and tissue engineering.Fil: Sanchez, Sara Serafina del V.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Honore, Stella Maris. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentin