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Use of computational realistic models for the cardiac ejection fraction calculation
No full textEjection 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 models, obtained
computationally, of the cardiac chamber called right ventricle. Normally, the geometric
hypothesis that makes this ventricle coincide with a pyramidal type geometric shape, is not
usually, fulfilled in subjects affected by several cardiac pathologies, so as an alternative to this
problem, the computational segmentation process is used to generate the morphology of the right
ventricle and from it proceeds to obtain, accurately, the ejection fraction value. In this sense, an
automatic strategy based on no-lineal filters, smart operator and region growing technique is
propose in order to generate the right ventricle ejection fraction. The results are promising due
we obtained an excellent correspondence between the manual segmentation and the automatic
one generated by the realistic models
Surface persistence of trace level deposits of highly energetic materials
No full textIn the fields of Security and Defense, explosive traces must be analyzed at the sites
of the terrorist events. The persistence on surfaces of these traces depends on the sublimation
processes and the interactions with the surfaces. This study presents evidence that the sublimation
process of these traces on stainless steel (SS) surfaces is very different than in bulk quantities.
The enthalpies of sublimation of traces of four highly energetic materials: triacetone triperoxide
(TATP), 2,4-dinitrotoluene (DNT), 2,4,6-trinitrotoluene (TNT), and 1,3,5- trinitrohexahydro-s-triazine
(RDX) deposited on SS substrates were determined by optical fiber coupled-grazing angle probe
Fourier Transform Infrared (FTIR) Spectroscopy. These were compared with enthalpies of sublimation
determined by thermal gravimetric analysis for bulk amounts and differences between them were
found. The sublimation enthalpy of RDX was very different for traces than for bulk quantities,
attributed to two main factors. First, the beta-RDX phase was present at trace levels, unlike the case of
bulk amounts which consisted only of the alpha-RDX phase. Second, an interaction between the RDX
and SS was found. This interaction energy was determined using grazing angle FTIR microscopy.
In the case of DNT and TNT, bulk and traces enthalpies were statistically similar, but it is evidenced
that at the level of traces a metastable phase was observed. Finally, for TATP the enthalpies were
statistically identical, but a non-linear behavior and a change of heat capacity values different from
zero was found for both trace and bulk phases
Level of knowledge of patients with Chronic Kidney Disease about their disease in Barranquilla Colombia
No full textObjetivo: determinar el nivel de conocimiento de los pacientes
con ERC a cerca de su enfermedad que asiste al
servicio de nefrología en una institución de salud.
Metodología: Se desarrolló un estudio descriptivo transversal,
se utilizó una muestra de 50 pacientes con ERC
mediante un muestreo por conveniencia; se aplicó la encuesta
Kidney Disease Questionnaire versión en español,
para el análisis de los datos se utilizó el software estadístico
SPSS. Ver. 22 (licencia universidad Simón Bolívar).
Resultados: Observamos una mayor incidencia de ERC
en hombres (64%) que en mujeres (36%), de igual manera
la mayoría de la población se encuentra entre las
edad de 66 a 70 años con un 34%, se encontró que los
usuarios desconoce los medicamentos que deben evitar y
desconocen el significado que tiene la alta presencia de
proteínas en la orina sobre los riñones
Conclusiones: Existe un bajo nivel de conocimiento de
los pacientes con ERC respecto a su enfermedad, específicamente
en el área de los efectos que tienen los medicamentos
sobre su organismo y los cambios que presenta
su cuerpo debido a la enfermedad, una de las principales
limitaciones presentes en el estudio fue que la población
con edad superior de 80 años no se logró incluir debido
al grado de dependencia cognitiva y funcional que presentaban.Objective: Determine the level of knowledge that patients
with CKD have about their disease whom attend a
nephrology service at a health institution.
Methodology: A descriptive transversal study was carried
out, a sample size of 50 patients with CKD was chosen
via convenience sampling; the Spanish version of the
Kidney Disease Questionnaire was utilized, statistical software
SPSS (ver. 22 Universidad Simon Bolivar license) was
used for data analysis.
Results: A higher incidence was found in men (64%)
compared to women (36%), the majority of the population
was between the ages of 66 and 70 years old (34%),
it was found that patients were unaware of prescription
drugs they should avoid nor did they know that the high
amount of protein found in their urine could affect their
kidneys.
Conclusions: CKD patients have a low level of knowledge
about their own disease, especially with regards to the effects,
medications have on their own organism as well as
the impact of the disease process on their own bodies´.
One of the principal limitations present in this study was
that the population older than 80 years old could not be
included in the study due to the level of cognitive and
functional decline they presented
Estrategias de optimización bi-objetivo para el proceso de pesaje multicabezal
No full textMultihead weighing processes are considered an important strategy in packaging companies. Multihead weighers are used for
dosing a wide range of products, from granules to large products. The packaging process consists of choosing a subset of
hoppers in the multihead weigher to form a product package. This paper proposes a set of filling strategies of hoppers to
reduce the variability in the weight of the produced packages. The strategies are evaluated through a bi-objective optimization
approach which aims to minimize the absolute difference between the target weight and the actual weight of the packages,
while trying to maximize the selection of those hoppers with more time in the packaging system. In the bi-objective approach,
the considered objectives are dynamically adjusted and managed in each packaging operation. In addition, the mathematical
model and the packing algorithm are developed and presented. The results of the process performance parameters are
obtained and analyzed to show the effectiveness of the proposed strategies. Also, conditions of minimum variability are
identified and those can be used by the packaging industry where multihead weighers are used.Los procesos de pesaje multicabezal son actualmente considerados una estrategia importante en empresas de envasado.
Maquinas pesadoras multicabezal son utilizadas para la dosificación de amplia gama de productos, desde granulados a
productos de gran tamaño. El proceso de envasado consiste en la selección de un subconjunto de tolvas en la pesadora
multicabezal para formar un paquete de producto. La presente investigación propone un conjunto de estrategias de llenado de
tolvas para reducir la variabilidad en el peso de los paquetes producidos. Las estrategias son evaluadas mediante un enfoque
de optimización bi-objeivo que busca minimizar la diferencia absoluta entre el peso objetivo y el peso real de los paquetes, al
tiempo que intenta maximizar la selección de aquellas tolvas con mayor tiempo en el sistema de envasado. En el enfoque biobjetivo,
los objetivos considerados son dinámicamente ajustados y gestionados en cada operación de envasado. Además, el
modelo matemático que representa nuestro problema y el algoritmo de envasado son desarrollados y presentados. Los
resultados de los parámetros de rendimiento del proceso son obtenidos y analizados como una medida de la efectividad de las
estrategias propuestas. Asimismo, las condiciones de mínima variabilidad son identificadas para motivar su uso en la
industria de envasado de producto en donde se utilicen máquinas de pesaje multicabezal
The role of green it in the non-functional software development requirements: Perspectives for functional design
No full textMany of the research carried out on green information technology or green
technologies has focused on reducing the environmental effect, on the design, development and
use of increasingly eco-efficient electronic devices, in terms of the machine, that is, the hardware;
but this trend has changed in recent years, due to the concern to cover all fronts in which green
information technology is part; what has allowed to generate studies and investigations in another
aspect, as it is the software. Some authors have addressed the issue, however, models,
descriptions or implementations in the area of software are still in short supply, whose main
rationale is eco-efficiency, that is, environmental strategies to reduce the impact of a product or
service by increasing the efficiency of resource utilization. The research emphasizes the
formulation of a guide based on the principles promulgated in green information technology as
a non-functional requirement in the analysis and design of software and incorporating this guide
in the software engineering projects of the systems engineering program of the Universidad
Francisco de Paula Santander, Seccional Ocaña, through the content of the green information
technology elective course and as an academic unit of the software engineering course
The Control of Conventionality and Judicial Dialogue in front of the Environment as a Subject of Protection and Reparation
No full textEl presente artículo tiene por objeto
el control de convencionalidad y su ejercicio
por los jueces administrativos, pretendiendo
en este caso efectuar un análisis del control
de convencionalidad y la doctrina conocida
como diálogo interjurisdiccional que propenda
por una concepción de mayor garantía del
medio ambiente como sujeto de protección
y reparación. Para ello, se utilizó un marco
metodológico de carácter cualitativo con la
técnica de análisis de discurso —de carácter
jurisprudencial— sobre múltiples providencias
de altas cortes colombianas y la Corte Interamericana
de Derechos Humanos, así como de
reconocidos doctrinarios, que permitan fortalecer
la propuesta, concluyendo que este diálogo sea
activo con una modificación de la dirección en
que se efectúe y que podrían ser las altas cortes nacionales las que fijen precedentes que la
Corte Interamericana pueda tomar como criterio
hermenéutico relevante que tengan por fin la
conformación de un ius commune interamericano
en favor del medio ambiente como sujeto
autónomo de protección y reparación.This article to control conventionality
and its exercise by administrative judges,
intending in this case to carry out an analysis of
conventionality control and the doctrine known
as interjurisdictional dialogue that encourages a
conception of greater guarantee of the environment
as subject of protection and repair. To this
end, a qualitative methodological framework was
used with the discourse analysis technique —of
a jurisprudential nature— on multiple measures
of the Colombian High Courts and the Inter-
American Court of Human Rights, as well as
recognized doctrines that allow strengthening
the proposal, concluding that this dialogue will
be active with a modification of the direction in
which it takes place, which could be the High
National Courts that set precedents that the
Inter-American Court can take as a relevant hermeneutical criterion that have as their purpose
the conformation of an inter-American
ius commune in favor of the environment as an
autonomous subject of protection and repair
Endophytic microorganisms for biocontrol of the phytopathogenic fungus Botrytis cinerea
No full textBotrytis cinerea is the most widely studied necrotrophic phytopathogenic fungus. It causes economic losses that are difficult to calculate due to the large number of hosts. While there are a wide array of fungicides on the market to control this phytopathogen, they are not considered sustainable in terms of the environment and human health. The search for new alternatives to control this phytopathogen has led to the use of endophytic microorganisms as biological control agents. Endophytic bacteria and endophytic fungi have been isolated from different plant species and some have proven effective in inhibiting B. cinerea. Furthermore, a significant number of fungistatic or fungicidal metabolites which could be used as alternative complementary chemical controls have been isolated from these fungi and bacteria. In this review, in addition to the metabolites which have shown fungicide activity against this phytopathogen, the different genera and species of endophytic bacteria and fungi are also considered. These have been isolated from various plant species and have displayed antagonistic activity against B. cinerea
Microbiological water quality and sources of contamination along the coast of the Department of Atlántico (Caribbean Sea of Colombia). Preliminary results
No full textMicrobiological sea water quality is a public health problem that has serious repercussions in the tourism and economy of Colombia. This study determines the concentrations of Escherichia coli, Enterococcus faecalis and Clostridium perfringens at eleven beach water points and seven streams along the coast of the Department of Atlántico, Colombia. In seawater, total E. coli, E. faecalis and C. perfringens concentrations were found between 16 and 572 cfu/100 mL, 7–450 cfu/100 ml and 2–125 cfu/100 ml, respectively. The highest counts were observed mainly on urbanised beaches and in correspondence with streams whose waters had a high concentration of faecal origin microorganisms, which represent a serious health risk factor for bathers. Relevant efforts have to be addressed to improve the microbiological quality of these beaches by the establishment of efficient wastewater management programs aimed at enhancing the efficiency of the local treatment plant and the control of illegal sewage pouring onto the coast
University-Industry-Government linkage to promote innovation at regional systems: Documentary research
No full textGestionar innovación en territorios representa una estrategia de diferenciación para lograr resultados satisfactorios en reportes de competitividad, por ello este trabajo está orientado a revisar la contribución en el fomento de la innovación en sistemas regionales desde los actores clave: universidades, empresas, estado y su vinculación, quienes han sido parte vital del constructo de principios de economías basadas en conocimiento. El análisis documental en fuentes secundarias ha permitido identificar que desde los sistemas regionales se requiere la integración de actores e instituciones clave orientados a proyectos articuladores orientados al fortalecimiento de las capacidades territoriales y los resultados tecnológicos del sistema.The state of the art on innovation has allowed the position which rank the concept like a key tool in processes of organizations at knowledge’s society, that characterizes the territories and regions of today, however, their appropriation still presents limitations on organizations, positioning itself as possible causes: the scarce investment in science and technology by some regions or the entrenched traditionalist thinking from some type of organizations, especially in contexts such as Latin American, where these limitations still prevail in the performance of various territorial actors including some business, higher education’s institutions and government agencies
Interest rates calculation in certain ordinary annuities
No full textCertain 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 using trial techniques, graphical methods or values present in pre-established tables. Through this article, a new robust methodology is proposed that calculates the useful numerical values to initialize the linear interpolation technique, which is used to calculate the interest rate linked to the certain ordinary annuity. The proposed methodology generates initialization values, one by default and the other by excess, which allow us to limit the value of the certain ordinary annuity interest rate considered. Finally, we generated a new strategy that constitutes a novel mathematical model for interest rates calculation in the context of certain ordinary annuity. The percentage relative error obtained indicates the excellent performance of the aforementioned mathematical model