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Obesity is a multifactorial pathology currently considered one of the main public health problems. Its prevalence is increasing dramatically in the last decades, reaching huge rates in Brazil and many other countries. Regardless of the factors associated with genetic predisposition, this pathology is often associated with abnormal food intake, and also with high consumption of caloric foods and sedentary habits. Thus, obesity is the result of an imbalance between food intake and energy expenditure. One of the greatest research interests in nutrition has currently been the dietetic determinants that may exert an influence on the process of food intake, as well as the role of foods on physiological, physical and chemical factors most related to the processes of satiation and satiety. Based on these aspects, this paper analyzes several research works to gain a better insight of the dietetic factors affecting food intake and body weight regulation. 相似文献
94.
We evaluated methylmercury (MHg) kinetics, dose--responses, and excretion in free-living adult Cory's shearwaters using a nondestructive multi-tissue approach. Elimination of MHg in blood comprised an initial fast phase, with half-time of 1 d, and a slow terminal phase with half-time between 44 and 65 d. Molt was a crucial factor in determining the rate of MHg elimination. Half-times were independent of dose. A relationship between steady-state blood concentrations and dietary intake of MHg was derived. Ratios between Hg concentrations in eggs or hatchlings' plumage and parental blood were independent of dose, with tissue--blood partition coefficients identical to those in controls. Dose--response relationships were linear. Females were subjected to Hg concentrations 18% higher than males but exhibited a 10% lower dose--response in blood. The difference is not fully accounted for by excretion into the egg and may be due to unidentified sex-related differences in physiology. Excretion rates into plumage showed no dose dependency but were higher (33% of intake) in birds exposed during molt than in birds dosed 2 months before the start of molt. Hg excretion through the skin in exfoliated epidermal cells that adsorb into plumage was estimated to represent 8% of the intake. The results of this study may be used in advanced modeling of the kinetics of MHg in adult birds to fill the current gap of a bioenergetic model for avian exposure to MHg. 相似文献
95.
Xavi Masip-Bruin Marcelo Yannuzzi Rene Serral-Gracia Jordi Domingo-Pascual Jose Enriquez-Gabeiras Maria Angeles Callejo Michel Diaz Florin Racaru Giovanni Stea Enzo Mingozzi Andrzej Beben Wojciech Burakowski Edmundo Monteiro Luís Cordeiro 《Communications Magazine, IEEE》2007,45(2):96-103
EuQoS is the acronym for "end-to-end quality of service support over heterogeneous networks", which is a European research project aimed at building an entire QoS framework, addressing all the relevant network layers, protocols, and technologies. This framework, which includes the most common access networks (xDSL, UMTS, WiFi, and LAN) is being prototyped and tested in a multidomain scenario throughout Europe, composing what we call the EuQoS system. In this article we present the novel QoS routing mechanisms that are being developed and evaluated in the framework of this project. The preliminary performance results validate the design choices of the EuQoS system, and confirm the potential impact this project is likely to have in the near future 相似文献
96.
Eric Monteiro Neil Pollock Ole Hanseth Robin Williams 《Computer Supported Cooperative Work (CSCW)》2013,22(4-6):575-607
In their initial articulation of the direction of the CSCW field, scholars advanced an open-ended agenda. This continuing commitment to open-ness to different contexts and approaches is not, however, reflected in the contents of the major CSCW outlets. The field appears to privilege particular forms of cooperative work. We find many examples of what could be described as ‘localist studies’, restricted to particular settings and timeframes. This focus on the ‘here and now’ is particularly problematic when one considers the kinds of large-scale, integrated and interconnected workplace information technologies—or what we are calling Information Infrastructures—increasingly found within and across organisations today. CSCW appears unable (or unwilling) to grapple with these technologies—which were at the outset envisaged as falling within the scope of the field. Our paper hopes to facilitate greater CSCW attention to Information Infrastructures through offering a re-conceptualisation of the role and nature of ‘design’. Design within an Information Infrastructures perspective needs to accommodate non-local constraints. We discuss two such forms of constraint: standardisation (how local fitting entails unfitting at other sites) and embeddedness (the entanglement of one technology with other apparently unrelated ones). We illustrate these themes through introducing case material drawn on from a number of previous studies. 相似文献
97.
João P. Monteiro Fátima M. Santos Ana S. Rocha João P. Castro-de-Sousa João A. Queiroz Luis A. Passarinha Cândida T. Tomaz 《Proteomics. Clinical applications》2015,9(1-2):187-202
The vitreous humor (VH) is the largest component of the eye. It is a colorless, gelatinous, highly hydrated matrix that fills the posterior segment of the eye between the lens and retina in vertebrates. In VH, a diversity of proteins that can influence retinal physiology is present, including growth factors, hormones, proteins with transporter activity, and enzymes. More importantly, the protein composition of VH has been described as being altered in a number of disease states. Therefore, attempts aiming at establishing a map of VH proteins and detecting putative biomarkers for ocular illness or protein fluctuations with putative physiologic significance were conducted over the last two decades, using proteomic approaches. Proteomic strategies often involve gel-based or LC techniques as sample fractioning approaches, subsequently coupled with MS procedures. This set of studies resulted in the proteomic characterization of a range of ocular disease samples, with particular incidence on diabetic retinopathy. However, practical therapeutic applications arising from these studies are scarce at the moment. A pertinent example of therapeutic targets arising from VH proteomics has emerged concerning vasoproliferative factors present in the vitreous, which should be involved in neovascularization and subsequent fibrovascular proliferation of the retina, in ocular disease context. Therefore, this review attempts to sum up the information acquired from the proteomic approaches to ocular disease conducted in VH samples, highlighting its clinical potential for disclosing ocular disease mechanisms and engendering pharmacological therapeutic treatments. 相似文献
98.
ABSTRACTUndirected graphical models have been successfully used to jointly model the spatial and the spectral dependencies in earth observing hyperspectral images. They produce less noisy, smooth, and spatially coherent land-cover maps and give top accuracies on many datasets. Moreover, they can easily be combined with other state-of-the-art approaches, such as deep learning. This has made them an essential tool for remote-sensing researchers and practitioners. However, graphical models have not been easily accessible to the larger remote-sensing community as they are not discussed in standard remote-sensing textbooks and not included in the popular remote-sensing software and toolboxes. In this tutorial, we provide a theoretical introduction to Markov random fields and conditional random fields-based spatial–spectral classification for land-cover mapping along with a detailed step-by-step practical guide on applying these methods using freely available software. Furthermore, the discussed methods are benchmarked on four public hyperspectral datasets for a fair comparison among themselves and easy comparison with the vast number of methods in literature which use the same datasets. The source code necessary to reproduce all the results in the paper is published on-line to make it easier for the readers to apply these techniques to different remote-sensing problems. 相似文献
99.
G. M. Espindola I. A. Reis L. S. Bins A. M. Monteiro 《International journal of remote sensing》2013,34(14):3035-3040
Region‐growing segmentation algorithms are useful for remote sensing image segmentation. These algorithms need the user to supply control parameters, which control the quality of the resulting segmentation. An objective function is proposed for selecting suitable parameters for region‐growing algorithms to ensure best quality results. It considers that a segmentation has two desirable properties: each of the resulting segments should be internally homogeneous and should be distinguishable from its neighbourhood. The measure combines a spatial autocorrelation indicator that detects separability between regions and a variance indicator that expresses the overall homogeneity of the regions. 相似文献
100.
Andre Felipe Monteiro Marcus Vinicius Azevedo Alexandre Sztajnberg 《Journal of Systems and Software》2013
This work proposes a reusable architecture that enables the self-configuration of a supporting infrastructure for Web server clusters using virtual machines. The goal of the architecture is to ensure service quality, evaluating how broadly it complies with the application's operating restrictions and proportionally acting on the configuration of physical servers (hosts) or virtual machines. In addition, through the rational use of resources, the proposal aims at saving energy. A prototype of the architecture was developed and a performance evaluation carried out with two different resource management approaches. This evaluation shows how fully functional and advantageous the proposal is in terms of using resources, avoiding waste, yet maintaining the application's quality of service within acceptable levels. The architecture also shows to be flexible enough to accept, with a reasonable amount of effort, different resource self-configuration policies. 相似文献