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Model of sustainable rural associative enterprise: the case of coffee and cocoa production in the municipality of Valledupar (Colombian Caribbean)
No full textThe purpose of this work is to show how the rural associative company model is used
for the production of Coffee and Cocoa in the Department of Cesar, Colombia, for
which it was necessary to identify the factors that led to its creation; the
characterization of its organizational structure; the description of its value chain and
alliances. The data were taken from the social and participatory interaction through a
structured interview with members of the board of directors of 10 associative
companies, five cocoa producers and 5 coffee producers who voluntarily agreed to
participate in the research. A review of documents provided by each company was
also carried out. As a common factor for the creation of the 10 participating
associations, the initiative of a group of producers interested in seizing the
opportunity of a business stands out. The value chains of the five coffee associative
companies are made up of primary and post-harvest production managed by their
associates; transformation infrastructure to obtain dry parchment coffee; three
companies have roasted and ground threshing infrastructure; and only two companies
have coffee-based beverage marketing points managed by the boards of directors. On
the other hand, in the value chain of the five cocoa companies, primary and postharvest
production is carried out by the associates and the association is responsible
for marketing cocoa almonds
Approaching the use of graphical interface in the operation of intelligent agents with medical images
No full textEn el presente artículo se da a conocer el estado del arte relativo al desarrollo de interfaz gráfica de usuario para la integración de técnicas de procesamiento de imágenes y operadores basados en máquinas inteligentes, orientada a la construcción de enfoques computacionales útiles en la rutina clínica y/o en la investigación relacionada con el diagnóstico de neoplasias malignas en el sistema gastrointestinal. Para ello, inicialmente se contextualiza a través de una fundamentación teórica la interfaz gráfica en el contexto de las imágenes médicas, lo cual sustenta las entradas principales de la matriz documental. La revisión documental de artículos científicos, libros, capítulos de libros, tesis de grado y posgrado referentes al objeto de estudio son sistematizados mediante la matriz documental como instrumento de recolección de información. De allí, y considerando un análisis de contenido, se exploraron sesenta y cuatro referencias bibliográficas
relacionadas con las entradas de la matriz documental. Los hallazgos develaron que en el contexto nacional y en el internacional ha ido creciendo el diseño de aplicativos para la integración de algoritmos matemático-computacionales con interfaz gráfica de usuario para el procesamiento y análisis de imágenes de tumores cancerígenos de estómago. No obstante, no se ha alcanzado aún una solución computacional
óptima.In this paper, we present the state of the art related to the development of graphic user interface for the integration of image processing techniques and operators based on machine learning, in this case, oriented to the construction of computational approaches useful in the clinical routine and/or in research related to the diagnosis of malignant neoplasms in the gastrointestinal system. In this sense, the graphical interface in the context of medical images is initially contextualized
through a theoretical foundation, which supports the main entries of the documentary matrix. The documentary review of scientific papers, books, book chapters, undergraduate and postgraduate theses related to the object of study are
systematized through the documentary matrix as an instrument for gathering information. From there, and considering a content analysis, sixty-four bibliographical references related to the entries of the documentary matrix are explored. The findings revealed an increase in the design of applications for the integration of mathematical-computational algorithms with graphical user interface for the processing and analysis of images of cancerous tumors of the stomach has grown. This increase has been both in the national and international context. However, an optimal computational solution has not yet been reached
Susceptibilidad genética frente al cáncer bucal por la infección del virus del papiloma humano
No full textLos carcinógenos ambientales y el virus del papiloma humano (VPH), son los primordiales responsables del cáncer bucal (CB), factores de susceptibilidad en el genoma humano juegan un papel modulador del riesgo, sin embargo no todos los individuos expuestos a estos carcinógenos padecen cáncer. El objetivo de la presente revisión es describir los principales factores de susceptibilidad genética frente a CB por la infección del VPH, realizando una búsqueda sistemática en tres bases de datos en inglés; donde finalmente solo 7 artículos cumplieron con los criterios de selección. Se muestran polimorfismos genéticos en tres categorías importantes relacionados con el VPH y participando en la oncogénesis, evidenciándose tres artículos relativos a la desregulación de los mecanismos de control del ciclo celular, un artículo referente a mutaciones en la vía de la apoptosis y tres artículos con respecto a polimorfismos en genes de respuesta inflamatoria e inmune. El estudio de la asociación de polimorfismos para el desarrollo de CB frente al VPH es evidente, aunque se mantiene en estudio, no siempre el patrón de oncogénesis de todos los CB se encuentran relacionados solo con la presencia del VPH, si no, a otros factores ambientales o epigenéticos.Environmental carcinogens and the human papillomavirus (HPV), are the primary responsible for oral cancer (CB), susceptibility factors in the human genome play a risk modulator role, however not all individuals exposed to these carcinogens suffer from cancer . The aim of the present review is to describe the main factors of genetic susceptibility to CB for HPV infection, carrying out a systematic search in three databases in English; where finally only 7 articles met the selection criteria. Genetic polymorphisms are shown in three important categories related to HPV and participating in oncogenesis, evidencing three articles related to the deregulation of cell cycle control mechanisms, an article referring to mutations in the pathway of apoptosis and three articles with respect to to polymorphisms in inflammatory and immune response genes. The study of the association of polymorphisms for the development of CB against HPV is evident, although it remains under study, not always the pattern of oncogenesis of all CB are related only to the presence of HPV, if not, to other factors environmental or epigenetic
Mechanisms of palmitate-induced lipotoxicity in osteocytes
No full textBackground: Lipotoxicity is defined as cellular toxicity observed in the presence of an abnormal accumulation of
fat and adipocyte-derived factors in non-fat tissues. Palmitic acid (PA), an abundant fatty acid in the bone
marrow and particularly in osteoporotic bones, affects osteoblastogenesis and osteoblast function, decreasing
their survival through induction of apoptosis and dysfunctional autophagy. In this study, we hypothesized that
PA also has a lipotoxic effect on osteocytes in vitro.
Methods: Initially, we tested the effect of PA on osteocyte-derived factors DKK1, sclerostin and RANKL. Then, we
tested whether PA affects survival and causes apoptosis in osteocytes. Subsequently, we investigated the effect of
PA on autophagy by detecting the membrane component LC3-II (Western blot) and staining them and lysosomes
with Lysotracker Red dye.
Results: PA decreases RANKL, DKK1 and sclerostin expression in osteocytes. In addition, we found that PA
induces apoptosis and reduces osteocyte survival. PA also caused autophagy failure identified by a significant
increase in LC3-II and a reduced number of autophagosomes/lysosomes in the cytoplasm.
Conclusion: In addition to the effects of PA on RANKL, DKK1 and sclerostin expression, which could have significant
deleterious impact on bone cell coupling and bone turnover, PA also induced apoptosis and reduced
autophagy in osteocytes. Considering that apoptosis and cell dysfunction are two common changes occurring in
the osteocytes of osteoporotic bone, our findings suggest that PA could play a role in the pathogenesis of the
disease. Suppression of these effects could bring new potential targets for therapeutic interventions in the future
Using text mining tools to define territorial competitiveness indicators
No full textFor this study, articles from the fields of Social Sciences; Economics; Econometrics and Finance; Business and Management; and Accounting have been monitored for the period from 1979 to 2017. VOSviewer® was used to create, visualize and explore bibliometric information from Scopus scientific database, for the identification and definition of territorial competitiveness indi-cators. It has generated preliminary conclusions using citation relationships be-tween journals, collaborative relationships between researchers, and coexistence relationships between scientific terms from the identified target literature
Susceptibilidad genética frente al cáncer bucal por infección del virus del papiloma humano
No full textLos carcinógenos ambientales y el virus del papiloma humano (VPH) son los principales responsables del cáncer bucal. Los factores de susceptibilidad en el genoma humano desempeñan un papel modulador del riesgo, sin embargo, no todos los individuos expuestos a los carcinógenos padecen cáncer. El objetivo de la presente revisión es describir los principales factores de susceptibilidad genética para cáncer bucal en individuos con infección por VPH. Se realizó una búsqueda sistemática en tres bases de datos en inglés; solo siete artículos cumplieron con los criterios de selección. Se registraron polimorfismos genéticos en tres categorías relacionados con el VPH y que participan en la oncogénesis. Se identificaron tres artículos relativos a la desregulación de los mecanismos de control del ciclo celular, uno relativo a mutaciones en la vía de la apoptosis y tres a polimorfismos en genes de respuesta inflamatoria e inmune. La asociación entre polimorfismos para el desarrollo de cáncer bucal y VPH es evidente, aunque continúa en estudio ya que no siempre el patrón de oncogénesis de las neoplasias bucales está relacionado con el VPH, sino con otros factores ambientales o epigenéticos.Environmental carcinogens and human papillomavirus (HPV) are the main responsible factors for oral cancer. Susceptibility factors in the human genome play a risk-modulating role; however not all individuals exposed to these carcinogens suffer from cancer. The purpose of the present review is to describe the main factors of genetic susceptibility to oral cancer due to HPV infection. A systematic search was carried out in three databases in English, with only 7 articles meeting the selection criteria. Genetic polymorphisms are shown in three categories, which are related to HPV and participate in oncogenesis. Three articles related to deregulation of cell cycle control mechanisms were identified, as well as one referring to mutations in the apoptosis pathway and three about polymorphisms in inflammatory and immune response genes. The association of polymorphisms for the development of oral cancer by HPV is evident, although it remains under study. Oral neoplasms’ oncogenesis pattern is not always associated with HPV, but with other environmental or epigenetic factors
The Importance of Tubular Function in Chronic Kidney Disease
No full textGlomerular filtration rate (GFR) and proteinuria-albuminuria are the renal functional
parameters currently used to evaluate chronic kidney disease (CKD) severity.
However, tubular secretion is another important renal functional parameter to be taken into
account since proximal tubule (PT) secretion, in particular, is a crucial renal mechanism for
endogenous organic cations, anions and drug elimination. The residual diuresis is a relevant
survival predictor in patients on dialysis, since their urine is produced by the glomerular and
tubular functions. It has been hypothesized that drugs which up-regulate some renal tubular
transporters could contribute to uremic toxin excretion, and nephroprevention. However, if
tubular transporters' down-regulation observed in CKD patients and experimental models is
a PT adaptation to avoid intracellular accumulation and damage from uremic toxins, consequently
the increase of toxin removal by inducing tubular transporters' up-regulation could be
deleterious to the kidney. Therefore, a deeper understanding of this phenomenon is currently
needed. In conclusion, tubular function has an important role for endogenous organic cations,
anions and drug excretion in CKD patients, and a deeper understanding of its multiple
mechanisms could provide new therapeutic alternatives in this population
Validation of a tool to disclose HIV diagnosis to children and adolescents
No full textIntroducción. La revelación del diagnóstico de VIH/Sida a niños y
adolescentes ha tenido beneficios y desafíos para las familias afectadas.
Objetivo. Validar la herramienta “Mi Dragón Dormido” para el proceso
de revelación del diagnóstico de VIH/Sida a menores de 15 años.
Materiales y métodos. Se seleccionaron 10 jueces expertos y 40
cuidadores de niños seropositivos y seronegativos para VIH mediante
muestreo no probabilístico intencional. Se administraron cuestionarios
estructurados para evaluar cinco componentes de eficacia y se realizó
análisis descriptivo de los datos y tabulación mediante el programa
IBM SPSS Versión 24.
Resultados. Jueces expertos y cuidadores determinaron que el
formato y los mensajes fueron claros y favorecieron la identificación
y aceptación. También indicaron que la herramienta permitió un
cambio de comportamiento en el público objetivo.
Conclusión. La herramienta es válida para apoyar el proceso de
revelación de diagnóstico a niños con VIH y demostró aceptación en
población seronegativa, lo que sugiere que puede ser utilizada en hogares
y contextos educativos para promover comportamientos que respalden
la salud, el bienestar general y la reducción de prácticas discriminatorias
hacia las personas con VIH.Introduction: The disclosure of the HIV/AIDS diagnosis to children
and adolescents has benefits and challenges for affected families.
Objective: To validate the tool Mi Dragón Dormido (My Sleeping
Dragon) during the process of disclosing an HIV/AIDS diagnosis to
children under the age of 15.
Materials and methods: 10 expert judges and 40 caregivers of
HIV-positive and HIV-negative children were selected using nonprobability
purposive sampling. Structured questionnaires were
applied to evaluate five efficacy components. A descriptive analysis
of data and tabulation were performed using IBM SPSS Version 24
software.
Results: Expert judges and caregivers determined that the format and
the messages were clear and favored identification and acceptance.
They also stated that the tool enabled behavior change in the target
audience.
Conclusion: The tool is valid for supporting the process of disclosure
of diagnosis to children with HIV and demonstrated acceptance in
HIV-negative populations, suggesting that it can be used in homes
and educational settings to promote behaviors that support health,
general well-being and the reduction of discriminatory practices
towards people with HIV
Intervention perspective: abilities for life in technical education young people
No full textObjetivo: Describir las habilidades para la vida en los aprendices
del Sena según el sexo, en la ciudad de Cúcuta - Colombia.
Metodología: El estudio se desarrolló desde la perspectiva
positivista y enfoque cuantitativo, el alcance del estudio
descriptivo de nivel comparativo, diseño no experimental. La
muestra fue aleatoria simple compuesta por 350 jóvenes entre
mujeres y hombre, que cumplieran los criterios de edad
18-25 años, estar matriculado en un plan técnico y tecnológico
en la institución de formación para el trabajo el semestre
2018B. La recolección de datos se desarrolló por medio del
test de habilidades para la vida1.
Resultados y Discusión: Teniendo en cuenta los hallazgos
de desempeño en las habilidades para la vida, tanto en hombre
como mujeres escolarizadas en educación para el trabajo
en programas técnicos y tecnólogos, se percibe similar desempeño
en las habilidades de relaciones interpersonales, no
obstante, algunos estudios evidencian diferencias de desempeño
en especial en habilidades específicas como asertividad
y confianza en sí mismo, siendo más alta en los hombres2.
Conclusiones: es pertinente aplicar a los programas de capacitación
laboral para jóvenes, estrategias de habilidades
para la vida para afianzar dichas habilidades a nivel superior.Objective: To describe the life skills of the apprentices of the
Sena according to the sex, in the city of Cucuta -Colombia.
Methodology: The study was developed from the positivist
perspective and quantitative approach, the scope of the
descriptive study of comparative level, non-experimental
design. The sample was simple random composed by 350
young people between women and men, who met the criteria
of age 18-25 years, being enrolled in a technical and
technological plan in the institution of training for work in the
semester 2018B. The data collection was developed through
the life skills test1.
Results and Discussion: Taking into account the findings
of performance in life skills, both in men and women enrolled
in work education in technical and technologists programs,
similar performance in interpersonal relationship skills is perceived,
however, some studies show differences in performance
especially in specific skills such as assertiveness and
self-confidence, being higher in men2.
Conclusions: It is pertinent to apply to life training programs
for youth, life skills strategies to strengthen these skills at a
higher level
On the proper use of linear regression: basic conceptualization through an example applied to health sciences
No full textLa regresión lineal es una de las técnicas estadísticas más
difundidas y con mayores posibilidades de aplicación en contextos
diversos; desde escenarios técnicos, prácticos o de
ingeniería; hasta situaciones vinculadas a las ciencias sociales,
del comportamiento o de la salud. Las ecuaciones de regresión
posibilitan la interpretación de fenómenos al modelar
parsimoniosamente la realidad, constituyéndose en una importante
herramienta de ayuda para académicos, investigadores
o profesionales. El objetivo del presente artículo de revisión
es el de suministrar una guía teórico-práctica sobre los
aspectos básicos de la regresión lineal, haciendo hincapié
en el desarrollo del método de mínimos cuadrados ordinarios
para obtener los estimadores de regresión, presentando las
fórmulas requeridas para ello y empleando un ejemplo relacionado
con la medicina para ilustrar el procedimiento. El nivel
matemático es relativamente básico, aunque se requerirá
de cierto conocimiento de estadística y álgebra matricial. El
caso analizado gira en torno al estudio sobre la prevalencia
de síndrome metabólico de la ciudad de Maracaibo, Venezuela.
Se utiliza como variable dependiente la resistencia a
la insulina a través del HOMA-2, y como regresores la edad,
el índice de masa corporal y la razón triglicéridos-colesterol.
También se ofrece la solución al problema mediante la utilización
del programa de código abierto R-Studio.Linear regression is one of the most widespread statistical
techniques and with greater possibilities of application in diverse
contexts; from technical, practical or engineering scenarios;
to situations related to social, behavioral and health
sciences. Regression equations make possible to interpret
phenomena by the parsimonious modeling of reality, becoming
an important tool of help for academics, researchers or
professionals. The aim of this review is to provide a theoretical-
practical guide on the basic aspects of linear regression,
emphasizing the development of the ordinary least squares
method to obtain the regression estimators, presenting the
formulas required for this and using an example related to
medicine to illustrate the procedure. The mathematical level
is relatively basic, although some knowledge of statistics and
matrix algebra will be required. The analyzed case revolves
around the study on the prevalence of metabolic syndrome
from the city of Maracaibo, Venezuela. Insulin resistance
measured by HOMA-2 is used as a dependent variable, and
age, body mass index and triglyceride-cholesterol ratio as
predictor variables. The solution to the problem is also offered
by using the R-Studio program