366 research outputs found
Contact between adult children and their divorced parents: Italy in a comparative perspective
This paper, based on a Multipurpose survey on a large national sample of Italian households which has made possible to analyse parent-child and grandparent-child dyads, explores the impact of marital instability on relationships with adult children and with grandchildren. As in other countries, the impact is more negative in the case of divorce than in case of widowhood and, in both cases, more negative for men than for women. It affects the threegenerational relationship and is not compensated by stronger horizontal kinship ties. The impact is most negative in the case of contacts, while in the case of material support it is more neutral and even positive for widowed parents, confirming the strong role played by need in Mediterranean countries in the case of the latter. Not only divorce/separation, also remarriage has a negative impact on intergenerational contacts. And in this case the impact is stronger for women than for men. An exploratory comparison with countries where divorce rates are higher and have a different gender culture suggests that although the impact of marital instability is negative in both cases, its intensity is higher in Italy. These results offer new insight into the working of strong family ties. These ties, particularly in the case of men, are more vulnerable to the dissolution of marital bonds than in countries with weak family ties. Finally, family ties are strongly mediated and constructed by women and through relationships between women. When a mother is no longer present alongside the father, even in the case of widowhood, fathers and grandfathers risk weakening the intergenerational link. --
A pulse EPR investigation on the structure of proteins and biomimetic model compounds involved in energy conversion
In the last decades Electron Paramagnetic Resonance spectroscopy has significantly developed as a versatile tool for the investigation of complex paramagnetic centers. Since then several microwave pulse sequences have been designed in order to disentangle the magnetic interactions between the unpaired electrons and the magnetically active surrounding. Despite their reactivity, paramagnetic centers are quite diffuse in biological systems, where they are usually involved in the key roles of the entire enzymatic activity of proteins. Many enzymes rely on paramagnetic transition metal centers for their catalytic role while different organic and metallic paramagnetic centers are essential in the whole photosynthetic process. In this thesis work advanced Electron Paramagnetic Resonance spectroscopy is exploited to deeply investigate the structure and the surrounding of three different classes of paramagnetic centers, which are present in proteins and artificial biomimetic systems and all being involved, directly or indirectly, in the sunlight energy conversion process that brings energy from the Sun to the Earth. The peptide environment of the active site of a protein is known to play a peculiar role in the fine tuning of the whole activity of the protein, for this reason the investigation of the surrounding of the paramagnetic center turn to be crucial for a correct and comprehensive description of the energy conversion pathway.
The first system here investigated is the reduced iron-sulfur cluster of the HydF protein, an enzyme involved in the correct maturation of the [Fe-Fe]-hydrogenase. Up to date the entire maturation pathway is still unclear, so that a multi-layered description at molecular level of the role of the HydF protein is of fundamental meaning. Then the investigation moves to the triplet state of the carotenoid involved in the photoprotection mechanism inside the Peridinin - Chlorophyll a – Protein. In this case a water molecule has been identified as an active and conserved player in the energy transfer process between the pigments. Finally, we have explored the feasibility of employing the photoexcited triplet state of tetraphenylporphyrin as a spin probe for the Double-Electron-Electron-Resonance technique on several artificial biomimetic compounds. The introduction of this novel spin probe approach will considerably improve the structural-investigation potential of this technique since porphyrins are widespread pigments, constituting the molecular core of chlorophylls, bacteriochlorophylls and heme groups. The application to a biological system, the Peridinin - Chlorophyll a – Protein antenna complex, has also been tested with very good and promising results.
For all these systems, Electron Paramagnetic Resonance spectroscopy proved to be a valuable and effective tool for investigating the systems hereafter reported, giving new insight into energy conversion and transfer mechanisms in biological systems from a structural point of view, highlighting how the fine tuning of the surrounding of the paramagnetic center at atomic level is crucial for the future design of biomimetic compounds able to efficiently convert solar energy into practical fuels. In addition the triplet state has been demonstrated to be a valuable spin probe for distance and orientation measurement in both biological and biomimetic systems, opening the possibility to exploit the triplet state as a probe for gaining structural data at molecular level
Does children’s union dissolution hurt elderly parents? Linked lives, divorce and mental health in Europe
Previous research has shown that parent’s union dissolution has negative consequences for individuals’ well-being, parent–child relationships and children’s outcomes. However, less attention has been devoted to the effects in the opposite direction, i.e. how children’s divorce affects parents’ well-being. We adopted a cross-country, longitudinal and multigenerational perspective to analyse whether children’s marital break-up is associated with changes in parents’ depressive symptoms. Using data from 17 countries and 5 waves of the Survey of Health, Ageing and Retirement in Europe (2004–2015), fixed effect linear regression models were estimated to account for time-constant social selection processes into divorce/separation. The results show that across European contexts parents’ depressive symptoms increased as one of their children divorced. Furthermore, we found that parents living in more traditional societies, such as Southern European ones, experienced higher increases in depression symptoms when a child divorced than those living in Nordic countries. Overall, the findings provide new evidence in support of both the notion of “linked lives” and a normative perspective of family life course events
CA19.9 antigen circulating in the serum of colon cancer patients: Where is it from?
CA19.9 antigen is a glycoprotein present in human serum and found elevated in various diseases. It is intensively studied since long time as a potential marker for managing cancers of the gastrointestinal tract, but its reliability is widely accepted only for pancreatic cancers. Here, we focused on the tetrasaccharide epitope (NeuAc\u3b12-3Gal\u3b21-3[Fuc\u3b11-4]GlcNAc) sialyl-Lewis a studying the biosynthesis, expression, and secretion in colon cancers and related cancer cell lines. We found that the \u3b21,3 galactosyltransferase \u3b23Gal-T5, responsible for sialyl-Lewis a synthesis, is dramatically reduced in colon adenocarcinomas, in terms of both transcript and enzyme activity levels. Moreover, no or very faint antigen is detectable in colon cancer homogenates, by dot-blot or enzyme immunoassay, while it is commonly evident in sera from different patients. In cancer cell lines synthesizing CA19.9, the amount of antigen secreted is proportional to that expressed on the cell surface, and depends on appreciable levels of \u3b23Gal-T5, which appear much higher than those measured in colon cancer specimens. Since colon cancers appear unable to synthesize relevant amount of CA19.9, we suggest that the antigen circulating in the serum of colon cancer patients may have a different and more complex origin than expected so far
Exploiting magnetic properties of Fe doping in zirconia
In this study we explore, both from theoretical and experimental side, the
effect of Fe doping in ZrO2 (ZrO2:Fe). By means of first principles simulation
we study the magnetization density and the magnetic interaction between Fe
atoms. We also consider how this is affected by the presence of oxygen
vacancies and compare our findings with models based on impurity band and
carrier mediated magnetic interaction. Experimentally thin films (~ 20 nm) of
ZrO2:Fe at high doping concentration are grown by atomic layer deposition. We
provide experimental evidence that Fe is uniformly distributed in the ZrO2 by
transmission electron microscopy and energy dispersive X-ray mapping, while
X-ray diffraction evidences the presence of the fluorite crystal structure.
Alternating gradient force magnetometer measurements show magnetic signal at
room temperature, however with low magnetic moment per atom. Results from
experimental measures and theoretical simulations are compared.Comment: 8 pages, 9 figures. JEMS 201
Family transfers and long-term care: An analysis of the WHO Study on global AGEing and adult health (SAGE).
BACKGROUND: Populations globally are ageing, resulting in increased need for long-term care. Where social welfare systems are insufficient, these costs may fall to other family members. We set out to estimate the association between long-term care needs and family transfers in selected low- and middle- income countries. METHODS: We used data from the World Health Organization's Study on global AGEing and adult health (SAGE). Using regression, we analysed the relationship between long-term care needs in older households and i) odds of receiving net positive transfers from family outside the household and ii) the amount of transfer received, controlling for relevant socio-demographic characteristics. RESULTS: The proportion of household members requiring long-term care was significantly associated with receiving net positive transfers in China (OR: 1.76; p = 0.023), Ghana (OR: 2.79; p = 0.073), Russia (OR: 3.50; p < 0.001). There was a statistically significant association with amount of transfer received only in Mexico (B: 541.62; p = 0.010). CONCLUSION: In selected LMICs, receiving family transfers is common among older households, and associated with requiring long-term care. Further research is needed to better understand drivers of observed associations and identify ways in which financial protection of older adults' long-term care needs can be improved
New active site oriented glyoxyl-agarose derivatives of Escherichia coli penicillin G acylase
<p>Abstract</p> <p>Background</p> <p>Immobilized Penicillin G Acylase (PGA) derivatives are biocatalysts that are industrially used for the hydrolysis of Penicillin G by fermentation and for the kinetically controlled synthesis of semi-synthetic β-lactam antibiotics. One of the most used supports for immobilization is glyoxyl-activated agarose, which binds the protein by reacting through its superficial Lys residues. Since in <it>E. coli </it>PGA Lys are also present near the active site, an immobilization that occurs through these residues may negatively affect the performance of the biocatalyst due to the difficult diffusion of the substrate into the active site. A preferential orientation of the enzyme with the active site far from the support surface would be desirable to avoid this problem.</p> <p>Results</p> <p>Here we report how it is possible to induce a preferential orientation of the protein during the binding process on aldehyde activated supports. A superficial region of PGA, which is located on the opposite side of the active site, is enriched in its Lys content. The binding of the enzyme onto the support is consequently forced through the Lys rich region, thus leaving the active site fully accessible to the substrate. Different mutants with an increasing number of Lys have been designed and, when active, immobilized onto glyoxyl agarose. The synthetic performances of these new catalysts were compared with those of the immobilized wild-type (wt) PGA. Our results show that, while the synthetic performance of the wt PGA sensitively decreases after immobilization, the Lys enriched mutants have similar performances to the free enzyme even after immobilization.</p> <p>We also report the observations made with other mutants which were unable to undergo a successful maturation process for the production of active enzymes or which resulted toxic for the host cell.</p> <p>Conclusion</p> <p>The desired orientation of immobilized PGA with the active site freely accessible can be obtained by increasing the density of Lys residues on a predetermined region of the enzyme. The newly designed biocatalysts display improved synthetic performances and are able to maintain a similar activity to the free enzymes. Finally, we found that the activity of the immobilized enzyme proportionally improves with the number of introduced Lys.</p
INTERACCIĂ“N GESTUAL PARA ENTORNOS DE INMERSIĂ“N ARQUEOLĂ“GICOS: TRABAJO EN CURSO
[EN] Archaeological data are heterogeneous (i.e., data-sheets and pictures, stratigraphic data, 3D models), and innovative
virtual reconstractuions helps to visualize and study those data. In this short paper, we describe our work in progress in
the design of an innovative way to interact with the complexity of a virtual reconstruction, using natural gestures and
advanced machine learning, in close collaboration with archeaeologists.[ES] Los datos arqueológicos son heterogéneos (por ejemplo, ficha técnica e imágenes, datos estratigráficos y modelos 3D),
y las nuevas tecnologĂas pueden ser capaces de ayudar en la visualizacion y el estudio de dichos datos. En este
documento se presenta nuestro trabajo en curso que describe el diseño de una forma innovadora de interactuar con la
complejidad de una reconstrucción virtual, mediante gestos naturales y avanzadas técnicas de aprendizaje, en directa
colaboración con los arqueólogos.Albertini, N.; Brogni, A.; Caramiaux, B.; Gillies, M.; Olivito, R.; Taccola, E. (2016). NATURAL GESTURE INTERACTION IN ARCHAEOLOGICAL VIRTUAL ENVIRONMENTS: WORK IN PROGRESS. En 8th International congress on archaeology, computer graphics, cultural heritage and innovation. Editorial Universitat Politècnica de València. 284-287. https://doi.org/10.4995/arqueologica8.2016.3400OCS28428
Local and system mechanisms for action execution and observation in parietal and premotor cortices
The action observation network (AON) includes a system of brain areas largely shared with action execution in both human and nonhuman primates. Yet temporal and tuning specificities of distinct areas and of physiologically identified neuronal classes in the encoding of self and others’ action remain unknown. We recorded the activity of 355 single units from three crucial nodes of the AON, the anterior intraparietal area (AIP), and premotor areas F5 and F6, while monkeys performed a Go/No-Go grasping task and observed an experimenter performing it. At the system level, during task execution, F6 displays a prevalence of suppressed neurons and signals whether an action has to be performed, whereas AIP and F5 share a prevalence of facilitated neurons and remarkable target selectivity; during task observation, F5 stands out for its unique prevalence of facilitated neurons and its stronger and earlier modulation than AIP and F6. By applying unsupervised clustering of spike waveforms, we found distinct cell classes unevenly distributed across areas, with different firing properties and carrying specific visuomotor signals. Broadly spiking neurons exhibited a balanced amount of facilitated and suppressed activity during action execution and observation, whereas narrower spiking neurons showed more mutually facilitated responses during the execution of one’s own and others’ action, particularly in areas AIP and F5. Our findings elucidate the time course of activity and firing properties of neurons in the AON during one’s own and others’ action, from the system level of anatomically distinct areas to the local level of physiologically distinct cell classes
PO-1068: Characterization of superparamagnetic, oxygen loaded NanoBubbles for hyperthermia and radiotherapy
- …