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Mostrando ítems 11-20 de 21

#### Use of computational realistic models for the cardiac ejection fraction calculation

(IOP Publishing, 2019)

Ejection fraction is one of the most useful clinical descriptors to determine the cardiac
function of a subject. For this reason, obtaining the value of this descriptor is of vital importance
and requires high precision. However, in the clinical routine, to generate the mentioned
descriptor value, a geometric hypothesis is assumed, obtaining an approximate value for this
fraction, usually by excess, and which is a dependent-operator. The aim of the present work is
to propose the accurate calculation of the ejection fraction from realistic ...

#### Mathematical argumentation in the classroom

(IOP Publishing, 2019)

The article shares some elements of comprehensive type about "mathematical
argumentation in the classroom"; whose analysis, was made from two fundamental categories
in the development of an oral mathematical argumentation process for the conviction,
contradiction and validation of a written mathematical argumentation process. The research
addressed two central categories of argumentation as a discursive form, the first one is the
epistemic position, and the second one is the discursive position that students unveil at the time
of mathematically ...

#### Semi-automatic detection of the evolutionary forms of visceral leishmaniasis in microscopic blood smears

(IOP Publishing, 2019)

Leishmaniasis is a complex group of diseases caused by obligate unicellular and
intracellular eukaryotic protozoa of the leishmania genus. Leishmania species generate diverse
syndromes ranging from skin ulcers of spontaneous resolution to fatal visceral disease. These
syndromes belong to three categories: visceral leishmaniasis, cutaneous leishmaniasis and
mucosal leishmaniasis. The visceral leishmaniasis is based on the reticuloendothelial system
producing hepatomegaly, splenomegaly and lymphadenopathy. In the present article, a ...

#### 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 ...

#### Newton-Raphson method initialization for non-analytical equations solution linked to anticipated annuities

(IOP Publishing, 2019)

The series of payments made in equal intervals of time is known, in the world of
financial mathematics, as an annuity. An anticipated annuity is one whose periodic payment
expires at the beginning of the established payment interval. The non-analytical equation that
allows us to calculate the interest rate, linked to the anticipated annuity, can be solved using
several numerical methods, in particular, the numerical method called Newton-Rhapson. The
main problem with this method is its initialization, which requires of one starting point ...

#### 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 ...

#### 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 ...

#### 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 ...

#### 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 ...

#### 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 ...