339 research outputs found
Going beyond telecenters to foster the digital inclusion of older people in Brazil: lessons learned from a rapid ethnographical study
Telecenters take on a prominent role within the current information and communications technology (ICT) ecosystem in Brazil. They are seen by a great many as a key means to foster the digital inclusion of the older population in the country. This paper draws upon a rapid ethnographic study conducted with 78 older people in a center that teaches computer classes to seniors in Brazil. The results show that providing older people with technological infrastructures is not enough to strengthen their digital inclusion if their basic and non-instrumental needs are not taken into consideration in defining educational activities to be carried out in public centers. Participants’ basic needs when it comes to interacting with ICT, such as coping with accessibility issues, were dynamic, whilst non-instrumental needs, fulfilled by using these technologies, such as interacting with relevant others, remained fairly constant throughout the study. Drawing on the results of the study, strategies for fostering the digital inclusion and well-being of older people in Brazil that go beyond telecenters are suggested
Temporal sequence of the human RBCs' vesiculation observed in nano-scale with application of AFM and complementary techniques
Based on the multimodal characterization of human red blood cells (RBCs), the link between the storage-related sequence of the nanoscale changes in RBC membranes in the relation to their biochemical profile as well as mechanical and functional properties was presented. On the background of the accumulation of RBCs waste products, programmed cell death and impaired rheological properties, progressive alterations in the RBC membranes including changes in their height and diameter as well as the in situ characterization of RBC-derived microparticles (RMPs) on the RBCs surface were presented. The advantage of atomic force microscopy (AFM) in RMPs visualization, even at the very early stage of vesiculation, was shown based on the results revealed by other reference techniques. The nanoscale characterization of RMPs was correlated with a decrease in cholesterol and triglycerides levels in the RBC membranes, proving the link between the lipids leakage from RBCs and the process of vesiculation
Secondary structure alterations of RBC assessed by FTIR-ATR in correlation to 2,3-DPG levels in mice
Irreversible alterations in the hemoglobin structure affect oxygen binding in human packed red blood cells
Spectroscopic signature of red blood cells in a D-galactose-induced accelerated aging model
This work presents a semi-quantitative spectroscopic approach, including FTIR-ATR and Raman spectroscopies, for the biochemical analysis of red blood cells (RBCs) supported by the biochemical, morphological and rheological reference techniques. This multi-modal approach provided the description of the RBC alterations at the molecular level in a model of accelerated aging induced by administration of D-galactose (D-gal), in comparison to natural aging. Such an approach allowed to conclude that most age-related biochemical RBC membrane changes (a decrease in lipid unsaturation and the level of phospholipids, or an increase in acyl chain shortening) as well as alterations in the morphological parameters and RBC deformability are well reflected in the D-gal model of accelerated aging. Similarly, as in natural aging, a decrease in LDL level in blood plasma and no changes in the fraction of glucose, creatinine, total cholesterol, HDL, iron, or triglycerides were observed during the course of accelerated aging. Contrary to natural aging, the D-gal model led to an increase in cholesterol esters and the fraction of total esterified lipids in RBC membranes, and evoked significant changes in the secondary structure of the membrane proteins. Moreover, a significant decrease in the phosphorous level of blood plasma was specific for the D-gal model. On the other hand, natural aging induced stronger changes in the secondary structures of the proteins of the RBCs' interior. This work proves that research on the aging mechanism, especially in circulation-related diseases, should employ the D-gal model with caution. Nonetheless, the D-gal model enables to imitate age-related rheological alterations in RBCs, although they are partially derived from different changes observed in the RBC membrane at the molecular level
FTIR, Raman and AFM characterization of the clinically valid biochemical parameters of the thrombi in acute ischemic stroke
Differential Affinity and Catalytic Activity of CheZ in E. coli Chemotaxis
Push–pull networks, in which two antagonistic enzymes control the
activity of a messenger protein, are ubiquitous in signal transduction pathways.
A classical example is the chemotaxis system of the bacterium
Escherichia coli, in which the kinase CheA and the
phosphatase CheZ regulate the phosphorylation level of the messenger protein
CheY. Recent experiments suggest that both the kinase and the phosphatase are
localized at the receptor cluster, and Vaknin and Berg recently demonstrated
that the spatial distribution of the phosphatase can markedly affect the
dose–response curves. We argue, using mathematical modeling, that the
canonical model of the chemotaxis network cannot explain the experimental
observations of Vaknin and Berg. We present a new model, in which a small
fraction of the phosphatase is localized at the receptor cluster, while the
remainder freely diffuses in the cytoplasm; moreover, the phosphatase at the
cluster has a higher binding affinity for the messenger protein and a higher
catalytic activity than the phosphatase in the cytoplasm. This model is
consistent with a large body of experimental data and can explain many of the
experimental observations of Vaknin and Berg. More generally, the combination of
differential affinity and catalytic activity provides a generic mechanism for
amplifying signals that could be exploited in other two-component signaling
systems. If this model is correct, then a number of recent modeling studies,
which aim to explain the chemotactic gain in terms of the activity of the
receptor cluster, should be reconsidered
D4.3 Implementation and evaluation plan of Cycle 2 pilots:Report containing internal deliverable outcomes ID4.3, ID4.6, ID4.8 and ID4.11
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