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1.
Water Resour Res ; 59(1): e2022WR033304, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37034824

RESUMO

River discharge has experienced diverse changes in the last decades due to modification of hydrological patterns, anthropogenic intervention, re-vegetation or annual and interannual climatic and atmospheric fluctuations. Assessing the recent changes in river discharge and understanding the main drivers of these changes is thus extremely important from theoretical and applied points of view. More specifically, here we want to draw attention toward the impacts of streamflow changes on reservoir storage and operation. We describe the hydrological dynamics of the Yesa reservoir draining catchment, located in the central Spanish Pyrenees, and characterize the reservoir operation modes over the last 60 years (1956-2020). We analyze concurrent climatic (precipitation, air temperature, drought index), atmospheric mechanisms, land cover (Normalized Different Vegetation Index) and discharge (inlet and outlet of Yesa reservoir) time-series. By using the wavelet transform methodology, we detect historical breakpoints in the hydrological dynamics at different time-scales. Distinctive periods are thus identified. More regular seasonal flows characterized the catchment's dynamics during the first decades of the study period, while the last decades were characterized by a high inter-annual variability. These changes are primarily attributed to the natural re-vegetation process that the catchment experienced. Furthermore, we related changes in atmospheric circulation with a decline of the long-term discharge temporal features. This research contributes to the understanding of long-term river discharge changes and helps to improve the reservoir management practices.

4.
J Eur Acad Dermatol Venereol ; 35(4): 988-994, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33098595

RESUMO

BACKGROUND: Confusion exists regarding interstitial granulomatous dermatitis (IGD) and palisaded neutrophilic and granulomatous dermatitis (PNGD). OBJECTIVE: To determine whether IGD and PNGD are two different entities, or whether they must be considered as two subtypes of the same reactive pattern, and thus whether the unification of the nomenclature is necessary. METHODS: Observational retrospective multicentre study of patients with IGD and PNGD evaluated between 1999 and 2019 and review of their clinical and histological features. RESULTS: We identified 52 patients (38 women and 14 men). Clinical and histological findings of IGD were observed in 88.4% of cases. The most common cutaneous lesions were plaques/macules (IGD) or annular plaques and papules/nodules (PNGD), located mostly on the limbs and trunk. The rope sign was developed in two patients with IGD that associated autoimmune disorders. Similar associated comorbidities (75%) were found in both entities, mainly autoimmune diseases (53.8%). In IGD, the infiltrate was predominantly lympho-histiocytic. Neutrophilic infiltrates, karyorrhexis and skin lesions with limited clinical course were mainly associated with PNGD biopsies. In biopsies with a limited recurrent course, a predominant lymphocytic inflammatory infiltrate was found. Collagen degeneration was present in 75.9% of cases. The floating sign was observed only in IGD type patients (63%). Overlapping histological findings were found in one fourth of cases, especially between IGD and interstitial granuloma annulare. Interface dermatitis, apparently unrelated to drug intake, was observed in 4 cases of IGD. CONCLUSION: We support the term reactive granulomatous dermatitis to unify both the clinical and histological findings of IGD and PNGD, and the overlapping between IGD and interstitial granuloma annulare. According to this, a spectrum of histological changes will be found depending on the clinical course of the skin lesions.


Assuntos
Doenças Autoimunes , Dermatite , Feminino , Granuloma , Humanos , Masculino , Neutrófilos , Estudos Retrospectivos
5.
J Eur Acad Dermatol Venereol ; 32(9): 1420-1426, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29512202

RESUMO

Cocaine is an alkaloid extracted from the leaves of the Erythroxylum coca plant that emerged in the 1970s as a fashionable drug among members of certain social backgrounds. Cocaine abuse is a problem of current interest, which is mostly hidden and underdiagnosed, but dramatically widespread among all socio-economic strata, and with an incidence which is increasing at an alarming rate. There are 1.5 million cocaine consumers in the USA. In Spain, the prevalence of consumption among the population between 15 and 65 years old is higher, reaching 3.1%. Because of this, it seems important to understand and recognize all the mucocutaneous manifestations of cocaine abuse which have been reported in the literature to clarify and to help dermatologists in their daily practice. In this article, we describe the principal mucocutaneous manifestations of cocaine abuse and we review isolated case reports which have been published in the literature. Because the dermatologist may deal with an unknown problem as well as with an already well-known history of cocaine abuse, it seems logical to separate the mucocutaneous manifestations into those which are frequent and highly suggestive, such as those caused by vascular injury, damage to mucosal membranes, infectious diseases or neutrophilic dermatosis, especially when suffered by young people and in consonance with other systemic manifestations and, those which have been reported in the literature as isolated case reports. We also summarize the main aspects of its pathogeny, principal pharmacodynamic and pharmacokinetic characteristics, and diagnostic tools.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/complicações , Dermatopatias Vasculares/etiologia , Dermatopatias Vasculares/patologia , Cocaína/farmacologia , Humanos , Mucosa Nasal/patologia , Rinite/induzido quimicamente , Rinite/patologia
7.
J Mech Behav Biomed Mater ; 65: 334-343, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27631171

RESUMO

The systematic development of subject-specific computer models for the analysis of personalized treatments is currently a reality. In fact, many advances have recently been developed for creating virtual finite element-based models. These models accurately recreate subject-specific geometries and material properties from recent techniques based on quantitative image analysis. However, to determine the subject-specific forces, we need a full gait analysis, typically in combination with an inverse dynamics simulation study. In this work, we aim to determine the subject-specific forces from the computer tomography images used to evaluate bone density. In fact, we propose a methodology that combines these images with bone remodelling simulations and artificial neural networks. To test the capability of this novel technique, we quantify the personalized forces for five subject-specific tibias using our technique and a gait analysis. We compare both results, finding that similar vertical loads are estimated by both methods and that the dominant part of the load can be reliably computed. Therefore, we can conclude that the numerical-based technique proposed in this work has great potential for estimating the main forces that define the mechanical behaviour of subject-specific bone.


Assuntos
Densidade Óssea , Modelos Biológicos , Tíbia/fisiologia , Suporte de Carga , Remodelação Óssea , Simulação por Computador , Análise de Elementos Finitos , Marcha , Humanos , Redes Neurais de Computação
8.
J Theor Biol ; 314: 1-9, 2012 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-22954469

RESUMO

Cell migration and proliferation has been modelled in the literature as a process similar to diffusion. However, using diffusion models to simulate the proliferation and migration of cells tends to create a homogeneous distribution in the cell density that does not correlate to empirical observations. In fact, the mechanism of cell dispersal is not diffusion. Cells disperse by crawling or proliferation, or are transported in a moving fluid. The use of cellular automata, particle models or cell-based models can overcome this limitation. This paper presents a stochastic cellular automata model to simulate the proliferation, migration and differentiation of cells. These processes are considered as completely stochastic as well as discrete. The model developed was applied to predict the behaviour of in vitro cell cultures performed with adult muscle satellite cells. Moreover, non homogeneous distribution of cells has been observed inside the culture well and, using the above mentioned stochastic cellular automata model, we have been able to predict this heterogeneous cell distribution and compute accurate quantitative results. Differentiation was also incorporated into the computational simulation. The results predicted the myotube formation that typically occurs with adult muscle satellite cells. In conclusion, we have shown how a stochastic cellular automata model can be implemented and is capable of reproducing the in vitro behaviour of adult muscle satellite cells.


Assuntos
Diferenciação Celular , Movimento Celular , Modelos Biológicos , Células Satélites de Músculo Esquelético/citologia , Algoritmos , Animais , Proliferação de Células , Células Cultivadas , Humanos , Camundongos , Camundongos Transgênicos , Reprodutibilidade dos Testes , Processos Estocásticos
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