313 research outputs found
Stability of reaction fronts in random walk simulations
A model of propagating reaction fronts is given for simple autocatalytic reactions and the stability of the propagating reaction fronts are studied in several numerical experiments. The corresponding random walk simulations - extending of a recent algorithm - make possible the simultaneous treatment of moving particles. A systematic comparison with the standard deterministic simulations highlight the advantages of the present stochastic approach. The main favor of the random walk simulation is that the initial perturbation has no strong effect on the stability of the front unlike in deterministic cases
PINHEIROS: AS RESILIÊNCIAS DE UM SÍTIO URBANO
The present article aims to verify if the surrounding area of what we know today as Largo da Batata, in the neighborhood of Pinheiros, is a point of social and urban resilience in São Paulo city. The analyzes of the several occupations of the urban site of Pinheiros, a traditional district of this city, since its official occupation in 1560 by the Jesuit priests, belonging to the Society of Jesus, until the informal occupations of urban collectives that appropriated it since 2014, are essential for this purpose. Through them a parallel may be drawn between public policies and urban connectivities and social movements resulting from them. Likewise, the approach of concepts such as topophilia, locus and genius loci are essential for the comprehension of the resilience phenomena pointed out in the course of this explanation, caused by the various forms of appropriation of this site, considered one of the oldest in the city of São Paulo.O presente artigo tem como objetivo verificar se a área envoltória do que conhecemos hoje como Largo da Batata, no bairro de Pinheiros, é um ponto de resiliência social e urbana dentro da cidade de São Paulo. As análises das diversas ocupações do sítio urbano de Pinheiros, tradicional bairro paulistano, desde a sua ocupação oficial, em 1560, pelos padres jesuítas, pertencentes à Companhia de Jesus, até as ocupações informais de coletivos urbanos que dela se apropriaram a partir de 2014, são imprescindíveis para tal propósito. Através deles, traçam-se paralelos entre as políticas públicas e conectividades urbanas e movimentos sociais delas decorrentes. Da mesma forma, a abordagem de conceitos como topofilia, locus e genius loci são essenciais para a compreensão dos fenômenos de resiliência, apontados no decorrer desta explanação, ocasionados pelas diversas formas de apropriação deste sítio, considerado um dos mais antigos da cidade de São Paulo
Collaboration in Palliative Care Networks in Urban and Rural Regions of Switzerland
Due to aging populations, the need for seamless palliative care provision is of central interest for western societies. An essential aspect of palliative care delivery is the quality of collaboration amongst palliative care providers. Therefore, the current research is based on Bainbridge's conceptual framework, which provides an outline for the evaluation of palliative care provision. This study is the first one to investigate the predictive validity of spatial distribution on the quantity of interaction amongst various palliative care providers. Furthermore, based on the familiarity principle, we examine whether the extent of collaboration influences the perceived quality of collaboration among palliative care providers in urban versus rural areas of Switzerland. Based on a population-representative survey of Swiss palliative care providers, the results of the current study show that professionals in densely populated areas report higher absolute numbers of interactions and are more satisfied with their collaborative practice. This indicates that palliative care providers who work in urban areas are better embedded into networks than their counterparts in more rural areas. The findings are especially important, considering that efficient collaboration is a prerequisite to achieve satisfactory patient outcomes. Conclusively, measures should be taken to foster collaboration in weakly interconnected palliative care networks
All in the name of work? Nonwork orientations as predictors of salary, career, satisfaction, and life satisfaction
Career development increasingly demands a successful integration of work and nonwork domains. Based on work-nonwork conflict and enrichment theories, this study explored the relationship between nonwork orientations (i.e., family, personal life, and community) and both objective (i.e., salary) and subjective (i.e., career satisfaction) career success and life satisfaction over a period of six months among a sample of 548 employees from Germany. The results generally support the enrichment perspective. Family orientation showed a positive relationship with career satisfaction. All three nonwork orientations, especially family orientation, were positively related to life satisfaction. We also explored gender and age effects but found no differences in nonwork orientations between young employees aged 25–34 years and older workers aged 50–59 years. Men showed lower levels of personal life orientation than women, but no differences in family or community orientation based on gender were found. We also did not observe gender x age interaction effects. We discuss the study's implications for a whole-life perspective on career development, career success, and well-being
An Experimental Investigation of Ultraweak Photon Emission from Adult Murine Neural Stem Cells
Neurons like other living cells may have ultraweak photon emission (UPE) during neuronal activity. This study is aimed to evaluate UPE from neural stem cells (NSC) during their serial passaging and differentiation. We also investigate whether the addition of silver nanoparticles (AgNPs) or enhancement of UPE (by AgNPs or mirror) affect the differentiation of NSC. In our method, neural stem and progenitor cells of subventricular zone (SVZ) are isolated and expanded using the neurosphere assay. The obtained dissociated cells allocated and cultivated into three groups: groups: I: cell (control), II: cell + mirror, and III: cell + AgNPs. After seven days, the primary neurospheres were counted and their mean number was obtained. Serial passages continuous up to sixth passages in the control group. Differentiation capacity of the resulting neurospheres were evaluated in vitro by immunocytochemistry techniques. Measurement of UPE was carried out by photomultiplier tube (PMT) in the following steps: at the end of primary culture, six serial cell passages of the control group, before and after of the differentiation for 5 minutes. The results show that neither mirror nor AgNPs affect on the neurosphere number. The UPE of the NSC in the sixth subculturing passage was significantly higher than in the primary passage (P < 0.05). AgNPs significantly increased the UPE of the NSC compared to the control group before and after the differentiation (P < 0.05). Also, the treatment with AgNPs increased 44% neuronal differentiation of the harvested NSCs. UPE of NSC after the differentiation was significantly lower than that before the differentiation in each groups, which is in appropriate to the cell numbers (P < 0.0001). The mirror did not significantly increase UPE, neither before nor after the differentiation of NSC. As a conclusion, NSC have UPE-properties and the intensity is increased by serial passaging that are significant in the sixth passage. The AgNPs increases the UPE intensity of NSC that pushes more differentiation of NSC to the neurons. The mirror was not effective in enhancement of UPE. As a result, UPE measurement may be suitable for assessing and studying the effects of nanoparticles in living cells and neurons.This work was supported by grant No. 94-01-01-10157 from Shiraz University of Medical Sciences, Shiraz, Iran. This article was a part of the thesis written by Esmaeil Fereydoni, MSc. student of Anatomy
Thirteen factors for a successful career
What determines career success? This question has occupied careers research, professional and career counselling, as well as individuals for decades. There is consensus amongst careers researchers that to develop oneself professionally, there is more needed than simply finding a job that matches one's strengths and interests. The current world of work is increasingly characterised by individual, self-directed careers over an ..
The ultrastructure and flexibility of thylakoid membranes in leaves and isolated chloroplasts as revealed by small-angle neutron scattering
We studied the periodicity of the multilamellar membrane system of granal chloroplasts in different isolated plant thylakoid membranes, using different suspension media, as well as on different detached leaves and isolated protoplasts—using small-angle neutron scattering. Freshly isolated thylakoid membranes suspended in isotonic or hypertonic media, containing sorbitol supplemented with cations, displayed Bragg peaks typically between 0.019 and 0.023 Å− 1, corresponding to spatially and statistically averaged repeat distance values of about 275–330 Å. Similar data obtained earlier led us in previous work to propose an origin from the periodicity of stroma thylakoid membranes. However, detached leaves, of eleven different species, infiltrated with or soaked in D2O in dim laboratory light or transpired with D2O prior to measurements, exhibited considerably smaller repeat distances, typically between 210 and 230 Å, ruling out a stromal membrane origin. Similar values were obtained on isolated tobacco and spinach protoplasts. When NaCl was used as osmoticum, the Bragg peaks of isolated thylakoid membranes almost coincided with those in the same batch of leaves and the repeat distances were very close to the electron microscopically determined values in the grana. Although neutron scattering and electron microscopy yield somewhat different values, which is not fully understood, we can conclude that small-angle neutron scattering is a suitable technique to study the periodic organization of granal thylakoid membranes in intact leaves under physiological conditions and with a time resolution of minutes or shorter. We also show here, for the first time on leaves, that the periodicity of thylakoid membranes in situ responds dynamically to moderately strong illumination. This article is part of a Special Issue entitled: Photosynthesis research for sustainability: Keys to produce clean energy
Resilience Against Traumatic Stress: Current Developments and Future Directions
Given the high prevalence of stress-related mental disorders, their impact on person, family, and society and the paucity of treatment options for most of these disorders, there is currently a pressing need for innovative approaches to deal with these issues and enhance well-being. One approach which has received increasing attention over the last decade is to shift our scientific and clinical focus from risk factors for psychopathology to factors promoting resilience and mental well-being. In order to summarize and evaluate the current state of scientific affairs on the biological basis of resilience, we provide an overview of the literature on animal and human studies of resilience. Because resilience can only truly be operationalized through longitudinal data collection and analyses, we focus primarily on longitudinal studies. This review shows that the concept of resilience is currently being operationalized, measured and even defined in widely variable manners, both within animal and human studies. We further provide an overview of existing and new strategies that could help promote resilience and which are proposed to be implemented more often in clinical situations. Finally, we summarize the challenges the field is facing and provide recommendations for future research
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