51 resultados para Oxidation processes and photochemistry
Resumo:
This paper examines the contributions that generativity in older age may make to the concept of successful ageing. To this end, two perspectives on successful ageing are described: successful ageing as a set of clinical criteria, and successful ageing as the application of adaptive processes aimed at achieving efficient functioning. After showing the limitations of the first perspective, particularly from a developmental point of view, the paper argues that the adaptive version of successful ageing helps to put ageing into a developmental frame, but needs to be complemented by identifying specific content and goals that guide these adaptive processes and establish new feasible gains for older people. Generativity in older age could play that role and provides a conceptual framework that enriches the concept of successful ageing, both by emphasising the social context in which people age and by highlighting a personal growth component.
Resumo:
Significance: Current lifestyles with high-energy diets and little exercise are triggering an alarming growth in obesity. Excess of adiposity is leading to severe increases in associated pathologies, such as insulin resistance, type 2 diabetes, atherosclerosis, cancer, arthritis, asthma, and hypertension. This, together with the lack of efficient obesity drugs, is the driving force behind much research. Recent Advances: Traditional anti-obesity strategies focused on reducing food intake and increasing physical activity. However, recent results suggest that enhancing cellular energy expenditure may be an attractive alternative therapy. Critical Issues: This review evaluates recent discoveries regarding mitochondrial fatty acid oxidation (FAO) and its potential as a therapy for obesity. We focus on the still controversial beneficial effects of increased FAO in liver and muscle, recent studies on how to potentiate adipose tissue energy expenditure, and the different hypotheses involving FAO and the reactive oxygen species production in the hypothalamic control of food intake. Future Directions: The present review aims to provide an overview of novel anti-obesity strategies that target mitochondrial FAO and that will definitively be of high interest in the future research to fight against obesity-related disorders.
Resumo:
Resum en anglès del projecte de recerca L'empresa xarxa a Catalunya. TIC, productivitat, competitivitat, salaris i beneficis a l'empresa catalana té com a objectiu principal constatar que la consolidació d'un nou model estratègic, organitzatiu i d'activitat empresarial, vinculat amb la inversió i l'ús de les TIC (o empresa xarxa), modifica substancialment els patrons de comportament dels resultats empresarials, en especial la productivitat, la competitivitat, les retribucions dels treballadors i el benefici. La contrastació empírica de les hipòtesis de treball l'hem feta per mitjà de les dades d'una enquesta a una mostra representativa de 2.038 empreses catalanes. Amb la perspectiva de l'impacte de la inversió i l'ús de les TIC no s'aprecia una relació directa entre els processos d'innovació digital i els resultats de l'activitat de l'empresa catalana. En aquest sentit, hem hagut de segmentar el teixit productiu català per a buscar les organitzacions en què el procés de coinnovació tecnològica digital i organitzativa és més present i en què la intensitat de l'ús del coneixement és un recurs molt freqüent per a poder copsar impactes rellevants en els principals resultats empresarials. Això és així perquè l'economia catalana, avui, presenta una estructura productiva dual.
Resumo:
We report on the study of nonequilibrium ordering in the reaction-diffusion lattice gas. It is a kinetic model that relaxes towards steady states under the simultaneous competition of a thermally activated creation-annihilation $(reaction$) process at temperature T, and a diffusion process driven by a heat bath at temperature T?T. The phase diagram as one varies T and T, the system dimension d, the relative priori probabilities for the two processes, and their dynamical rates is investigated. We compare mean-field theory, new Monte Carlo data, and known exact results for some limiting cases. In particular, no evidence of Landau critical behavior is found numerically when d=2 for Metropolis rates but Onsager critical points and a variety of first-order phase transitions.
Resumo:
The present document should be seen as one more contribution to the debate to the reform processes and a small guide to these processes and their latest outcomes.
Resumo:
This article details the use of photographic rectification as support for the graphic documentation of historical and archaeological heritage and specifically the southern facade of the Torre del Pretori (Praetorium Tower) in Tarragona. The Praetorium Tower is part of a larger monumental complex and one of the towers that connected different parts of the Tarraco Provincial Forum, the politic-administrative centre of the ancient capital of Hispania Citerioris. It is therefore a valuable example of the evolution of Roman urban architecture. The aim of this project is to provide accurate graphic documentation of the structure to facilitate the restoration and conservation of the tower, as well as to provide a more profound architectural and archaeological understanding of the Roman forum. The use of photographic rectification enabled us to overcome the spatial and time difficulties involved in collecting data caused by the size and location of the building. Specific software made it easier to obtain accurate two-dimensional images. For this reason, in our case, photographic rectification helped us to make a direct analysis of the monument and facilitated interpretation of the architectural stratigraphy. We currently separate the line of research into two concepts: the construction processes and the architecture of the building. The documentation collected permitted various analyses: the characterisation of the building modules, identification of the tools used to work the building materials, etc. In conclusion, the use of orthoimages is a powerful tool that permits the systematic study of a Roman building that has evolved over the centuries and is now in a modern urban context.
Resumo:
Resveratrol has been shown to have beneficial effects on diseases related to oxidant and/or inflammatory processes and extends the lifespan of simple organisms including rodents. The objective of the present study was to estimate the dietary intake of resveratrol and piceid (R&P) present in foods, and to identify the principal dietary sources of these compounds in the Spanish adult population. For this purpose, a food composition database (FCDB) of R&P in Spanish foods was compiled. The study included 40 685 subjects aged 3564 years from northern and southern regions of Spain who were included in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Spain cohort. Usual food intake was assessed by personal interviews using a computerised version of a validated diet history method. An FCDB with 160 items was compiled. The estimated median and mean of R&P intake were 100 and 933 mg/d respectively. Approximately, 32% of the population did not consume RΠ The most abundant of the four stilbenes studied was trans-piceid (53·6 %), followed by trans-resveratrol (20·9 %), cis-piceid (19·3 %) and cis-resveratrol (6·2 %). The most important source of R&P was wines (98·4 %) and grape and grape juices (1·6 %), whereas peanuts, pistachios and berries contributed to less than 0·01 %. For this reason the pattern of intake of R&P was similar to the wine pattern. This is the first time that R&P intake has been estimated in a Mediterranean country.
Resumo:
The control of the right application of medical protocols is a key issue in hospital environments. For the automated monitoring of medical protocols, we need a domain-independent language for their representation and a fully, or semi, autonomous system that understands the protocols and supervises their application. In this paper we describe a specification language and a multi-agent system architecture for monitoring medical protocols. We model medical services in hospital environments as specialized domain agents and interpret a medical protocol as a negotiation process between agents. A medical service can be involved in multiple medical protocols, and so specialized domain agents are independent of negotiation processes and autonomous system agents perform monitoring tasks. We present the detailed architecture of the system agents and of an important domain agent, the database broker agent, that is responsible of obtaining relevant information about the clinical history of patients. We also describe how we tackle the problems of privacy, integrity and authentication during the process of exchanging information between agents.
Resumo:
This paper aims to better understand the development of students’ learning processes when participating actively in a specific Computer Supported Collaborative Learning system called KnowCat. To this end, a longitudinal case study was designed, in which eighteen university students took part in a 12-month (two semesters) learning project. During this time period, the students followed an instructional process, using some elements of KnowCat (KnowCat key features) design to support and improve their interaction processes, especially peer learning processes. Our research involved both supervising the students’ collaborative learning processes throughout the learning project and focusing our analysis on the qualitative evolution of the students’ interaction processes and on the development of metacognitive learning processes. The results of the current research reveal that the instructional application of the CSCL-KnowCat system may favour and improve the development of the students’ metacognitive learning processes. Additionally, the implications of the design of computer supported collaborative learning networks and pedagogical issues are discussed in this paper.
The transtheoretical model in weight management: Validation of the Processes of Change Questionnaire
Resumo:
Objective: The processes of change implied in weight management remain unclear. The present study aimed to identify these processes by validating a questionnaire designed to assess processes of change (the P-Weight) in line with the transtheoretical model. The relationship of processes of change with stages of change and other external variables is also examined. Methods: Participants were 723 people from community and clinical settings in Barcelona. Their mean age was 32.07 (SD = 14.55) years; most of them were women (75.0%), and their mean BMI was 26.47 (SD = 8.52) kg/m2. They all completed the P-Weight and the stages of change questionnaire (SWeight), both applied to weight management, as well as two subscales from the Eating Disorders Inventory-2 and Eating Attitudes Test-40 questionnaires about the concern with dieting. Results: A 34-item version of the PWeight was obtained by means of a refinement process. The principal components analysis applied to half of the sample identified four processes of change. A confirmatory factor analysis was then carried out with the other half of the sample, revealing that the model of four freely correlated first-order factors showed the best fit (GFI = 0.988, AGFI = 0.986, NFI = 0.986, and SRMR = 0.0559). Corrected item-total correlations (0.322-0.865) and Cronbach"s alpha coefficients (0.781-0.960) were adequate. The relationship between the P-Weight and the S-Weight and the concern with dieting measures from other questionnaires supported the validity of the scale. Conclusion: The study identified processes of change involved in weight management and reports the adequate psychometric properties of the P-Weight. It also reveals the relationship between processes and stages of change and other external variables.
Resumo:
Resveratrol has been shown to have beneficial effects on diseases related to oxidant and/or inflammatory processes and extends the lifespan of simple organisms including rodents. The objective of the present study was to estimate the dietary intake of resveratrol and piceid (R&P) present in foods, and to identify the principal dietary sources of these compounds in the Spanish adult population. For this purpose, a food composition database (FCDB) of R&P in Spanish foods was compiled. The study included 40 685 subjects aged 35-64 years from northern and southern regions of Spain who were included in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Spain cohort. Usual food intake was assessed by personal interviews using a computerised version of a validated diet history method. An FCDB with 160 items was compiled. The estimated median and mean of R&P intake were 100 and 933 mg/d respectively. Approximately, 32% of the population did not consume RΠ The most abundant of the four stilbenes studied was trans-piceid (53·6 %), followed by trans-resveratrol (20·9 %), cis-piceid (19·3 %) and cis-resveratrol (6·2 %). The most important source of R&P was wines (98·4 %) and grape and grape juices (1·6 %), whereas peanuts, pistachios and berries contributed to less than 0·01 %. For this reason the pattern of intake of R&P was similar to the wine pattern. This is the first time that R&P intake has been estimated in a Mediterranean country.
Identification-commitment inventory (ICI-Model): confirmatory factor analysis and construct validity
Resumo:
The aim of this study is to confirm the factorial structure of the Identification-Commitment Inventory (ICI) developed within the frame of the Human System Audit (HSA) (Quijano et al. in Revist Psicol Soc Apl 10(2):27-61, 2000; Pap Psicól Revist Col Of Psicó 29:92-106, 2008). Commitment and identification are understood by the HSA at an individual level as part of the quality of human processes and resources in an organization; and therefore as antecedents of important organizational outcomes, such as personnel turnover intentions, organizational citizenship behavior, etc. (Meyer et al. in J Org Behav 27:665-683, 2006). The theoretical integrative model which underlies ICI Quijano et al. (2000) was tested in a sample (N = 625) of workers in a Spanish public hospital. Confirmatory factor analysis through structural equation modeling was performed. Elliptical least square solution was chosen as estimator procedure on account of non-normal distribution of the variables. The results confirm the goodness of fit of an integrative model, which underlies the relation between Commitment and Identification, although each one is operatively different.
Resumo:
S u b s u r face fluid flow plays a significant role in many geologic processes and is increasingly being studied in the scale of sedimentary basins and geologic time perspective. Many economic resources such as petroleum and mineral deposits are products of basin scale fluid flow operating over large periods of time. Such ancient flow systems can be studied through analysis of diagenetic alterations and fluid inclusions to constrain physical and chemical conditions of fluids and rocks during their paleohy d r og e o l ogic evolution. Basin simulation models are useful to complement the paleohy d r og e o l ogic record preserved in the rocks and to derive conceptual models on hydraulic basin evolution and generation of economic resources. Different types of fluid flow regimes may evo l ve during basin evolution. The most important with respect to flow rates and capacity for transport of solutes and thermal energy is gr avitational fluid flow driven by the topographic configuration of a basin. Such flow systems require the basin to be elevated above sea level. Consolidational fluid flow is the principal fluid migration process in basins below sea level, caused by loading of compressible rocks. Flow rates of such systems are several orders of magnitude below topogr a p hy driven flow. Howeve r, consolidation may create significant fluid ove rpressure. Episodic dewatering of ove rpressured compart m e n t s m ay cause sudden fluid release with elevated flow velocities and may cause a transient local thermal and chemical disequilibrium betwe e n fluid and rock. This paper gives an ove rv i ew on subsurface fluid flow processes at basin scale and presents examples related to the Pe n e d è s basin in the central Catalan continental margin including the offshore Barcelona half-graben and the compressive South-Pyrenean basin.
Resumo:
The effects of the addition of heated oils to feeds (3%, w/w) and the dietary supplementation with a-tocopheryl acetate (TA; 100 mg/kg) and Zn (200 mg/kg) on rabbit tissue fatty acid (FA) composition and on the Zn, Cu, Fe and Se content in meat were assessed. Heating unrefined sunflower oil (SO) at 558C for 245 h increased its content in primary oxidation products and reduced its a-tocopherol content. However, this did not significantly affect tissue FA composition. Heating SO at 1408C for 31 h increased its content in secondary oxidation products and in some FA isomers asc9,t11-CLA and di-trans CLA. This led to increases in di-trans CLA in liver and in t9,c12-18:2 in meat. The c9,t11-CLA was the most incorporated CLA isomer in tissues. The dietary supplementation with a-TA did not affect the FA composition of plasma, liver or meat. The cooking of vacuum-packed rabbit meat at 788C for 5 min reduced significantly but slightly its polyunsaturated FA content. The dietary supplementation with Zn did not modify the content of Zn, Fe or Se in meat, but it reduced its Cu content. On the other hand, it increased the content of some FAs in meat when SO heated at 1408C for 31 h was added to feeds.
Resumo:
This paper presents a first analysis on local electronic participatory experiences in Catalonia. The analysis is based on a database constructed and collected by the authors. The paper carries out an explanatory analysis of local initiatives in eparticipationand off line participation taking into account political variables (usually not considered in this kind of analysis) but also classical socio-economic variables that characterise municipalities. Hence, we add a quantitative analysis to the numerous case studies on local e-participation experiences. We have chosen Catalonia because is one of the European regions with more initiatives and one that has enjoyed considerable local governmental support to citizen participation initiatives since the 80s. The paper offers a characterisation of these experiences and a first explanatory analysis, considering: i) the institutional context in which these experiences are embedded, ii) the characteristics of the citizen participation processes and mechanisms on-line, and iii) a set of explanatory variables composed by the population size, thepolitical adscription of the mayor, the electoral abstention rate, age, income and level ofeducation in the municipality. The model that we present is explanatory for the municipalities with more than 20,000 inhabitants but it is not for the fewer than 20,000inhabitants. Actually, the number of participatory activities developed by these last municipalities is very low. Among all the variables, population size becomes the mostinfluential variable. Political variables such as political party of the mayor and the localabstention rate have a certain influence but that have to be controlled by population size.