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1.
J Environ Manage ; 202(Pt 1): 268-275, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-28735211

RESUMEN

Rainfall-induced soil erosion is a major threat, especially in agricultural soils. In the Mediterranean belt, vineyards are affected by high soil loss rates, leading to land degradation. Plantation of new vines is carried out after deep ploughing, use of heavy machinery, wheel traffic, and trampling. Those works result in soil physical properties changes and contribute to enhanced runoff rates and increased soil erosion rates. The objective of this paper is to assess the impact of the plantation of vineyards on soil hydrological and erosional response under low frequency - high magnitude rainfall events, the ones that under the Mediterranean climatic conditions trigger extreme soil erosion rates. We determined time to ponding, Tp; time to runoff, Tr; time to runoff outlet, Tro; runoff rate, and soil loss under simulated rainfall (55 mm h-1, 1 h) at plot scale (0.25 m2) to characterize the runoff initiation and sediment detachment. In recent vine plantations (<1 year since plantation; R) compared to old ones (>50 years; O). Slope gradient, rock fragment cover, soil surface roughness, bulk density, soil organic matter content, soil water content and plant cover were determined. Plantation of new vineyards largely impacted runoff rates and soil erosion risk at plot scale in the short term. Tp, Tr and Tro were much shorter in R plots. Tr-Tp and Tro-Tr periods were used as connectivity indexes of water flow, and decreased to 77.5 and 33.2% in R plots compared to O plots. Runoff coefficients increased significantly from O (42.94%) to R plots (71.92%) and soil losses were approximately one order of magnitude lower (1.8 and 12.6 Mg ha-1 h-1 for O and R plots respectively). Soil surface roughness and bulk density are two key factors that determine the increase in connectivity of flows and sediments in recently planted vineyards. Our results confirm that plantation of new vineyards strongly contributes to runoff initiation and sediment detachment, and those findings confirms that soil erosion control strategies should be applied immediately after or during the plantation of vines.


Asunto(s)
Agricultura , Movimientos del Agua , Granjas , Lluvia , Suelo , Vitis
2.
Cureus ; 16(5): e59808, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38846222

RESUMEN

Lymphatic filariasis is endemic in a few states of India and is one of the most common public health concerns. Wuchereria bancrofti (W. bancrofti) is the most common parasite that causes lymphatic filariasis in India. Microfilariae have been commonly found in the peripheral blood and body fluid, as well as demonstrated in fine needle aspirates (FNA) and bronchial cytology. They have been rarely reported in bone marrow aspirates. Due to the nocturnal periodicity of W. bancrofti, it may be missed in peripheral blood during the day. Though peripheral eosinophilia is a presenting feature of filariasis, it may be absent in the majority of cases, as in this case. We report an incidental finding of W. bancrofti in the bone marrow aspirate of a 72-year-old male who had chronic kidney disease.

3.
Med Image Anal ; 4(2): 111-21, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10972325

RESUMEN

We present a general method to study the dissymmetry of anatomical structures such as those found in the human brain. Our method relies on the estimate of 3D dissymmetry fields, the use of 3D vector field operators, and T2 statistics to compute significance maps. We also present a fully automated implementation of this method which relies mainly on the intensive use of a 3D non-rigid inter-patient matching tool. Such a tool is applied successively between the images and their symmetric versions with respect to an arbitrary plane, both to realign the images with respect to the mid-plane of the subject and to compute a dense 3D dissymmetry map. Inter-patient matching is also used to fuse the data of a population of subjects. We then describe three main application fields: the study of the normal dissymmetry within a given population, the comparison of the dissymmetry between two populations, and the detection of the significant abnormal dissymmetries of a patient with respect to a reference population. Finally, we present preliminary results illustrating these three applications for the case of the human brain.


Asunto(s)
Encéfalo/anatomía & histología , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Afasia/patología , Encéfalo/patología , Simulación por Computador , Epilepsias Parciales/patología , Lateralidad Funcional , Humanos , Imagenología Tridimensional , Masculino
5.
IEEE Trans Med Imaging ; 27(4): 425-41, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18390341

RESUMEN

A critical issue in image restoration is the problem of noise removal while keeping the integrity of relevant image information. Denoising is a crucial step to increase image quality and to improve the performance of all the tasks needed for quantitative imaging analysis. The method proposed in this paper is based on a 3-D optimized blockwise version of the nonlocal (NL)-means filter (Buades, et al., 2005). The NL-means filter uses the redundancy of information in the image under study to remove the noise. The performance of the NL-means filter has been already demonstrated for 2-D images, but reducing the computational burden is a critical aspect to extend the method to 3-D images. To overcome this problem, we propose improvements to reduce the computational complexity. These different improvements allow to drastically divide the computational time while preserving the performances of the NL-means filter. A fully automated and optimized version of the NL-means filter is then presented. Our contributions to the NL-means filter are: 1) an automatic tuning of the smoothing parameter; 2) a selection of the most relevant voxels; 3) a blockwise implementation; and 4) a parallelized computation. Quantitative validation was carried out on synthetic datasets generated with BrainWeb (Collins, et al., 1998). The results show that our optimized NL-means filter outperforms the classical implementation of the NL-means filter, as well as two other classical denoising methods [anisotropic diffusion (Perona and Malik, 1990)] and total variation minimization process (Rudin, et al., 1992) in terms of accuracy (measured by the peak signal-to-noise ratio) with low computation time. Finally, qualitative results on real data are presented .


Asunto(s)
Algoritmos , Artefactos , Encéfalo/anatomía & histología , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Procesamiento de Señales Asistido por Computador
6.
Artículo en Inglés | MEDLINE | ID: mdl-16685872

RESUMEN

We propose to segment Multiple Sclerosis (MS) lesions overtime in multidimensional Magnetic Resonance (MR) sequences. We use a robust algorithm that allows the segmentation of the abnormalities using the whole time series simultaneously and we propose an original rejection scheme for outliers. We validate our method using the BrainWeb simulator. To conclude, promising preliminary results on longitudinal multi-sequences of clinical data are shown.


Asunto(s)
Encéfalo/patología , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Esclerosis Múltiple/diagnóstico , Reconocimiento de Normas Patrones Automatizadas/métodos , Algoritmos , Inteligencia Artificial , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Procesamiento de Señales Asistido por Computador
7.
Biotechnol Bioeng ; 83(5): 608-17, 2003 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-12827703

RESUMEN

Acidolysis of butteroil with free conjugated linoleic acid (CLA) was studied in a packed bed reactor containing an immobilized Candida antarctica (fraction B) lipase. Kinetic data were used to develop quantitative reversible rate expressions of the general Michaelis-Menten form that also incorporate a term for first-order deactivation of the enzyme. The extent of incorporation of CLA in the triacylglycerols of butteroil was characterized for reactions carried out at several temperatures (namely 45 degrees, 50 degrees, and 55 degrees C) with different weight ratios of butteroil to CLA (namely 10:1 and 2:1). At the optimum operating temperature of 50 degrees C, similar levels of incorporation of CLA (60% to 85%) were achieved at low space times (<3 h) for both 10:1 and 2:1 (w/w) ratios of butteroil to CLA.


Asunto(s)
Reactores Biológicos/microbiología , Mantequilla/microbiología , Candida/crecimiento & desarrollo , Candida/metabolismo , Grasas Insaturadas en la Dieta/metabolismo , Ácido Linoleico/biosíntesis , Lipasa/metabolismo , Modelos Biológicos , Simulación por Computador , Estudios de Factibilidad , Proteínas Fúngicas
8.
Med Pediatr Oncol ; 11(4): 263-8, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6310358

RESUMEN

During 1967-78, cancer was diagnosed in 870 children living in the Province of Torino. Survival until the end of 1978 is reported separately for cases diagnosed in 1967-70, in 1971-74, and in 1975-78. Comparisons between the three series indicate a statistically significant (p less than 0.05) increase in survival rates for children with leukemia and cancer of the central nervous system as well as a nonstatistically significant increase for children with lymphoma (both Hodgkin's and non-Hodgkin's). No consistent changes in time were noticed for neuroblastomas, nephroblastomas, soft tissue sarcomas, and retinoblastomas. Survival rates for both types of lymphomas and for leukemias (at least for cases diagnosed after 1975) were very similar to corresponding population-derived data from the U.S. and other Western countries. Rates for other cancers were relatively poor in the Province of Torino. It is suggested that relatively high care standards are easier to achieve in the case of childhood cancers requiring chemotherapy than in cancers commonly treated through radiotherapy and/or surgery.


Asunto(s)
Neoplasias/mortalidad , Factores de Edad , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Italia , Neoplasias Renales/mortalidad , Leucemia/mortalidad , Masculino , Factores Sexuales , Tumor de Wilms/mortalidad
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