170 research outputs found
Attitude and speed in young people. Implementation of a program of driver education
Contemporary Theories of change of attitudes defends that these depends on the way to think, to act and to feel of the people. If we touch upon each one of these three main components related between we can influence in the predisposition to act. The application of a program of speed self-control to ample of young drivers, using a design pretest- postest with control group and using a Factor Analysis shows that is possible the change of attitudes
Actitudes y velocidad en jóvenes. : Aplicación de un programa de educación vial
Las teorías contemporáneas del cambio de actitudes defienden que éstas dependen de la manera de pensar, actuar y sentir de las personas. Si se incide en cada uno de estos tres factores íntimamente relacionados entre si podemos influir en la predisposición a actuar. La aplicación de un programa de autocontrol de velocidad a una muestra de preconductores, utilizando un diseño pretest-postest con grupo control y utilizando un análisis factorial pone de manifiesto que es posible el cambio de actitudes en los jóvenesContemporary theories of change of attitudes defends that these depends on the way to think, to act and to feel of the people. If we touch upon each one of these three main components related between we can influence in the predisposition to act. The application of a program of speed self-control to ample of young drivers, using a design pretest-postest with control group and using a Factor Analysis shows that is possible the change of attitude
Structural investigation of homonuclear Pt2 and heteronuclear PdPt complexes containing a metal-metal bond bridged by hydrido and sulfido ligands
The complex [Pt2(/.t-H)(#-S)(dppe)2](PF6) undergoes a displacive order-disorder transformation at ca 230 K. The low-temperature structure is ordered with one cation-anion pair as the asymmetric unit in space group P2Jn. At room temperature the b axis is halved and the space group is P2/n, imposing crystallographic twofold rotation symmetry on both ions; the anion shows major disorder and there is probably minor disorder in the cation, but its internal geometry remains essentially unchanged. The heteronuclear complex [PdPt(ft-H)(/.t-S)(dppe)2](PF6) is isostructural with the Pt2 complex at room temperature. All three structures have been determined crystallographically and both complexes have been extensively characterized by NMR spectroscopy, unambiguously confirming the genuine heteronuclear nature of the mixed-metal complex and the presence of the bridging hydride ligand
The sea urchin metallothionein system: Comparative evaluation of the SpMTA and SpMTB metal-binding preferences.
Metallothioneins (MTs) constitute a superfamily of ubiquitous metal-binding proteins of low molecular weight and high Cys content. They are involved in metal homeostasis and detoxification, amongst other proposed biological functions. Two MT isoforms (SpMTA and SpMTB) have been reported in the echinoderm Strongylocentrotus purpuratus (sea urchin), both containing 20 Cys residues and presenting extremely similar sequences, although showing distinct tissular and ontogenic expression patterns. Although exhaustive information is available for the Cd(II)-SpMTA complex, this including the full resolution of its 3D structure, no data has been reported concerning either SpMTA Zn(II) and Cu(I) binding properties, or the characterization of SpMTB at protein level. In this work, both the SpMTA and SpMTB isoforms, as well as their separate α and β domains, have been recombinantly synthesized in the presence of Zn(II), Cd(II) or Cu(II), and the corresponding metal complexes have been analyzed using electrospray mass spectrometry, and CD, ICP-AES and UV-vis spectroscopies. The results clearly show a better performance of isoform A when binding Zn(II) and Cd(II), and of isoform B when coordinating Cu(I). Thus, our results confirm the differential metal binding preference of SpMTA and SpMTB, which, together with the reported induction pattern of the respective genes, highlights how also in Echinodermata the MT polymorphism may be linked to the evolution of different physiological roles
Structural Lesions of Proteins Connected to Lipid Membrane Damages Caused by Radical Stress: Assessment by Biomimetic Systems and Raman Spectroscopy
Model systems constituted by proteins and unsaturated lipid vesicles were used to gain more insight into the effects of the propagation of an initial radical damage on protein to the lipid compartment. The latter is based on liposome technology and allows measuring the trans unsaturated fatty acid content as a result of free radical stress on proteins. Two kinds of sulfu rcontaining proteins were chosen to connect their chemical reactivity with membrane lipid transformation, serum albumins and metallothioneins. Biomimetic systems based on radiation chemistry were used to mimic the protein exposure to different kinds of free radical stress and Raman spectroscopy to shed light on protein structural changes caused by the free radical attack. Among the amino acid residues, Cys is one of the most sensitive residues towards the attack of free radicals, thus suggesting that metal-Cys clusters are good interceptors of reactive species in metallothioneins, together with disulfides moieties in serum albumins. Met is another important site of the attack, in particular under reductive conditions. Tyr and Phe are sensitive to radical stress too, leading to electron transfer reactions or radical-induced modifications of their structures. Finally, modifications in protein folding take place depending on reactive species attacking the protein
Two unconventional Metallothioneins in the apple snail Pomacea Bridgesii have lost their metal specificity during adaptation to freshwater habitats
Metallothioneins (MTs) are a diverse group of proteins responsible for the control of metal homeostasis and detoxification. To investigate the impact that environmental conditions might have had on the metal-binding abilities of these proteins, we have characterized the MTs from the apple snail Pomacea bridgesii, a gastropod species belonging to the class of Caenogastropoda with an amphibious lifestyle facing diverse situations of metal bioavailability. P. bridgesii has two structurally divergent MTs, named PbrMT1 and PbrMT2, that are longer than other gastropod MTs due to the presence of extra sequence motifs and metal-binding domains. We have characterized the Zn(II), Cd(II), and Cu(I) binding abilities of these two MTs after their heterologous expression in E. coli. Our results have revealed that despite their structural differences, both MTs share an unspecific metal-binding character, and a great ability to cope with elevated amounts of different metal ions. Our analyses have also revealed slight divergences in their metal-binding features: PbrMT1 shows a more pronounced Zn(II)-thionein character than PbrMT2, while the latter has a stronger Cu(I)-thionein character. The characterization of these two unconventional PbrMTs supports the loss of the metal-binding specificity during the evolution of the MTs of the Ampullariid family, and further suggests an evolutionary link of this loss with the adaptation of these gastropod lineages to metal-poor freshwater habitats
Modular Evolution and Population Variability of Oikopleura dioica Metallothioneins
Chordate Oikopleura dioica probably is the fastest evolving metazoan reported so far, and thereby, a suitable system in which to explore the limits of evolutionary processes. For this reason, and in order to gain new insights on the evolution of protein modularity, we have investigated the organization, function and evolution of multi-modular metallothionein (MT) proteins in O. dioica. MTs are a heterogeneous group of modular proteins defined by their cysteine (C)-rich domains, which confer the capacity of coordinating different transition metal ions. O. dioica has two MTs, a bi-modular OdiMT1 consisting of two domains (t-12C and 12C), and a multi-modular OdiMT2 with six t-12C/12C repeats. By means of mass spectrometry and spectroscopy of metal-protein complexes, we have shown that the 12C domain is able to autonomously bind four divalent metal ions, although the t-12C/12C pair -as it is found in OdiMT1- is the optimized unit for divalent metal binding. We have also shown a direct relationship between the number of the t-12C/12C repeats and the metal-binding capacity of the MTs, which means a stepwise mode of functional and structural evolution for OdiMT2. Finally, after analyzing four different O. dioica populations worldwide distributed, we have detected several OdiMT2 variants with changes in their number of t-12C/12C domain repeats. This finding reveals that the number of repeats fluctuates between current O. dioica populations, which provides a new perspective on the evolution of domain repeat proteins
The relationship between awareness of road safety measure and accident involvement in pre-drivers : the basis of a road safety programme
Objectives: This research aims to carry out a first validation of the QAR-Precon screening questionnaire applied in Catalonia during the drivers' initial training, analyse the differences in risky road user behaviour according to two main variables: whether they had any experience of an accident and sex and examine the different risky road user patterns of pre-drivers. Methods: In order to group the questionnaire variables together, an exploratory factorial analysis (principal component analysis (PCA)) was used. Subsequently, the reliability coefficients of the questionnaire and the subscales were calculated. Lastly, ANOVA models were used to compare differences in the whole sample and a cluster analysis was performed to identify different risky pre-driver groups. Results: The factorial analysis (PCA) reveals the existence of five risk factors (speed and risk, external circumstances, distraction, alcohol and driving and other elements of driving) that explain 44.6% of the variance. More males than females reported that they had a higher tendency to take risks in all the risky factors exposed and injured pre-drivers reported less awareness of road safety than pre-drivers who had not been injured. A two-cluster solution indicated that it was possible to distinguish a group of pre-drivers who engaged in high risky behaviour (high group) from the group who engaged in moderate and low levels of risky road user behaviour (low group). Conclusions: The implications of these findings for programme designs and training initiatives to improve efficiency in reducing the accident rate are discusse
The Zn- or Cu-thionein character of a metallothionein determines its metal load when synthesized in physiological (metal-unsupplemented) conditions
The present work comprises the recombinant synthesis of four metallothioneins (MTs) in metal-unsupplemented cultures and the characterization of the recovered metal complexes by means of analytical and spectrometric techniques. The four MTs are two Drosophila (MtnA and MtnB), one yeast (Crs5), and one mouse (mMT1) metallothionein isoforms. These four MTs exhibit distinct metal binding preferences, from a clear Cu-thionein character to a definite Zn-thionein nature, respectively. Although in all cases, the only metal ion present in the purified complexes is Zn²+, our results highlight an inherently different behaviour of those two types of MTs, in conditions that would mimic their synthesis in physiological environments. Therefore, intrinsically different roles can be hypothesized for the constitutively-produced MT peptides in the absence of any metal overload, depending on their Zn- or Cu-thionein character
La figura del coordinador o coordinadora de coparentalidad (CP)en el marco legal catalán y estatal. La designa del CP.
This article reviews the legislative history on the instruments available to family judges to help families reduce post-divorce conflict: the creation of the first family courts, the first psychosocial teams, family access centers, the implementation of family mediation and coparenting coordination. Secondly, it presents the justification for the introduction of the parenting coordinator in the Catalan and Spanish legal system and in the international framework. Finally, it reviews the designation and functions assigned to the co-parenting coordinator in some court resolutions. Judges appreciate the complexity of the nature of family conflicts where the solutions can be more emotional than judicial, and seek new instruments, less legal and more psychosocial.Este artículo revisa la evolución legislativa sobre los instrumentos a disposición del juez de familia para ayudar a las familias en situación de ruptura de pareja a reducir la conflictividad, desde la creación de los primeros juzgados de familia y los primeros equipos psicosociales hasta los puntos de encuentro familiar, la implementación de la mediación familiar y la coordinación de parentalidad. A continuación, presenta la justificación para la aparición de la figura del coordinador de parentalidad en el ordenamiento jurídico catalán y estatal y en el marco internacional. En tercer lugar, revisa la designación y las funciones otorgadas al coordinador de parentalidad en algunas sentencias. Los jueces aprecian la complejidad de los conflictos familiares cuya solución es más emocional que judicial y buscan nuevos instrumentos, menos legales y más psicosociales
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