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Space-occupying lesions identification in mammary glands using a mixed computational strategy
(IOP Publishing, 2019)
Abstract. The mammary pathology can manifest itself in multiple ways and originates spaceoccupying
lesions. The breast cancer is a space-occupying lesion, which is highly prevalent,
especially in women, and worldwide it is one of the leading causes of morbidity and mortality
in this population. The main image modality for breast cancer detection is the magnetic
resonance but this kind of image modality introduces several imperfections that affect the
image quality. Some of these imperfections or problems are: inhomogeneity in the ...
Large cells cancer volumetry in chest computed tomography pulmonary images
(IOP Publishing, 2019)
Lung cancer is the leading oncological cause of death in the world. As for
carcinomas, they represent between 90% and 95% of lung cancers; among them, non-small cell
lung cancer is the most common type and the large cell carcinoma, the pathology on which this
research focuses, is usually detected with the computed tomography images of the thorax.
These images have three big problems: noise, artifacts and low contrast. The volume of the
large cell carcinoma is obtained from the segmentations of the cancerous tumor generated, in a
semi-automatic ...
Interest rates calculation in certain ordinary annuities
(IOP Publishing, 2019)
Certain annuities are annuities whose payments occur on fixed dates; while a certain ordinary annuity is one in which payments are made at the end of each established period. The calculation of the interest rate, which governs the certain ordinary annuity, involves the use of a non-analytical equation that requires the application of numerical techniques to obtain the value of the aforementioned rate. The literature indicates that any of these techniques requires one or several numerical values for initialization, which generally are estimated ...
Renal lithiasis detection in uro-computed tomography using a non-parametric technique
(IOP Publishing, 2019)
Renal lithiasis is the pathology that causes nephritic colic, which is one of the most frequent reasons for consultation in emergency medical services. According to the size, location, hardness and number of stones present in the urinary system, usually in the human kidney, it is established to which form of treatment is suitable for the patient. These kidney stones can be analyzed by means of biopsy or imaging modalities such as computed tomography images. This type of images has challenging problems called noise, artifacts and low contrast. In ...
Volumetric quantification in ovarian pathology using abdomino-pelvic computed tomography
(IOP Publishing, 2019)
Pathological ovary is categorized into cystic tumors, solid tumors and mixed,
according to the content of the affected ovary. Accordingly, the degree of benignity or
malignity thereof is established. The imaging study for the preliminary morphological
assessment of PO is ultrasound, in its pelvic and transvaginal modalities, for which wellestablished
criteria are available. Once the ultrasound findings suggest malignancy,
complementary studies such as abdominal-pelvic tomography images and tumor markers are
requested. This type of images ...
Semi-automatic detection of hepatic tumor in computed tomography images
(IOP Publishing, 2019)
In this work, the main purpose is develop a computational segmentation strategy for
liver tumor semiautomatic detection. This strategy considers three-dimensional computed
tomography images and it consists of techniques application that, on the one hand, diminish the
noise and detect the edges of the objects present in those images and, on the other hand, generate
the liver tumor morphology. For this, the sequence of techniques composed of gaussian
smoothing, gradient magnitude, median filter, region growing and binary morphological dilation
are ...
Left atrial appendage automatic segmentation, in computed tomography images
(IOP Publishing, 2019)
The left atrial appendage is one of the anatomical places where most frequently
blood thrombi occur. When migrating from the appendage, these thrombi, become blood
emboli that, potentially, can compromise the physiology and/or anatomy of cardiac or cerebral
blood vessels, being able to generate cerebrovascular events. The left atrial appendage
segmentation is very difficult due, mainly, to its location and the identical densitometric
information presents into of this appendage and around of the left atrium. In this paper, an
automatic ...
Assessment of left ventricle dynamic from cardiac magnetic resonance imaging by means a correspondence approach
(IOP Publishing, 2020)
In this research, an approach to assess the heart dynamics is reported. The
cardiac magnetic resonance images are considered for assessing the left ventricle motion and
deformation. The shape of the cavity is obtained by means a segmentation procedure based
on a clustering algorithm at an initial instant. This three-dimensional structure is used to
establish a region of interest around the border of the structure. An optical flow method allows
determining the displacement vector of this region and then defining the shapes of the cavity
during ...
Uncertainty as key element in the analysis of X–ray angiography images
(IOP Publishing, 2020)
The X–ray angiography images are routinely used to assess the blood vessels. The
acquisition procedure considers a medical imaging system which allows obtaining views of the
vessel while the blood flows thought them. The X–ray source is influenced on the region to be
viewed and then, the projection of the all anatomical structures in the champ of view is shown
through an image intensifier. The information of the blood vessel is impacted for the other
structures. Additionally, the blood and the contrast product required in the acquisition are ...
The rubric as an assessment strategy in the mathematical argumentation process
(IOP Publishing, 2020)
The article shares the proposal of an analytical rubric as a strategy for the assessment and monitoring of learning outcomes in students who develop an argumentative plot from the mathematics field, to solve any problem situation in daily life. The study was based on the theory of mathematical argumentation proposed by Duval and the contributions of León and Calderón, as well as the dimensions presented to us by the logical frameworks in the design of analytical rubrics. The research was developed under the social critical paradigm through the ...