231 research outputs found
Regulation of human pancreas hormone secretion by autonomic innervation
No full textDiabetes mellitus is a silent killer doing away with one person every 10 seconds. We speak of diabetes when the organism cannot control the right level of glucose in the blood. The hormones insulin and glucagon secreted by the islets of Langerhans are the major players maintaining glucose homeostasis. In the living organism, the function of the islets is orchestrated by their interaction with other organs through the vasculature and with the nervous system. Most of our current knowledge of islet biology has been obtained by using mouse models, but caution is needed, as mice are not simply small humans. Indeed, recent studies have revealed that the cell composition and architecture of the human islet are different from that of mouse islets. Thus, other important features such as nervous regulation of islet function may also be different.The work in this thesis aimed to identify the role of innervation for islet function. Our hypothesis is that autonomic and paracrine signals are involved in islet function and that the relative role of these components varies among species. To identify the sympathetic and parasympathetic components of innervation as well as their cellular targets we used immunohistochemical staining of human and mouse pancreatic sections. In contrast to mouse, human islets are devoid of parasympathetic innervation. Instead, human alpha cells possess the machinery for exocytosis of acetylcholine, the major parasympathetic neurotransmitter. Our findings suggest that human islets depend less on neural cholinergic input than mouse islets. Alpha cells secrete acetylcholine as a paracrine signal priming the human beta cell to respond optimally to subsequent increases in glucose concentration. In addition, noradrenergic fibers contact few endocrine cells in the human islet and preferentially innervate smooth muscle cells of the islet vasculature. This suggests that sympathetic innervation regulates hormone secretion by controlling the blood flow rather than modulating endocrine cell function directly.By taking advantage of our recently developed noninvasive anterior chamber of the eye imaging platform we were able to study the role of innervation in the maintenance of glucose homeostasis in vivo. We studied the process of reinnervation and revascularization of intraocular islet grafts and showed that islets orchestrate the process of engraftment to restore their original microenvironment. Islet grafts from two different mouse strains and human xenografts showed innervation patterns similar to those in pancreatic sections in situ. Islet grafts displayed the characteristic fenestrae of the pancreatic vascular endothelium independently of the origin of the new vessels. In addition, the model allowed controlling the fraction of the graft vasculature that is contributed by the donor islet endothelial cells to the point that the original donor vasculature of the islet is restored. Recording graft function while manipulating the eye’s neural input through the pupillary light reflex revealed functional differences in parasympathetic innervation between the two mouse strains. The eye platform also allowed us to follow cell dynamics during immune responses, which will enable investigations aimed at clarifying the role of innervation in the pathogenesis of autoimmune diabetes.To study human islet biology in vivo we further adopted the eye model by transplanting human islets into the eye of diabetic immune compromised mice. Human xenografts reversed diabetes and tightly controlled plasma glucose concentrations. Moreover, our results provided the first real time monitoring of revascularization and blood flow inside human islets and graft function could be modulated by local drug administration. Our findings establish a “humanized” mouse model to investigate human islet biology in vivo that will allow addressing how nervous input affects endocrine function or blood flow in human islets. The physiological relevance of the anterior chamber of the eye model is further underscored by the therapeutic potential as a novel transplantation site to treat type 1 diabetic patients.List of scientific papersI. Rayner Rodriguez-Diaz, Midhat H. Abdulreda, Alexander L. Formoso, Itai Gans, Camilo Ricordi, Per-Olof Berggren, Alejandro Caicedo (2011). Autonomic axons in the human Endocrine pancreas show unique innervation patterns. Cell Metabolism. Jul 6;14(1):45-54. https://doi.org/10.1016/j.cmet.2011.05.008 II. Rayner Rodriguez-Diaz, Robin Dando, M. Caroline Jacques-Silva, Alberto Fachado, Judith Molina, Midhat H. Abdulreda, Camilo Ricordi, Stephen D. Roper, Per-Olof Berggren, Alejandro Caicedo (2011). Acetylcholine is released by human alpha cells as a paracrine signal to prime beta cell insulin secretion. Nat Med. Jul 19;17(7):888-92. https://doi.org/10.1038/nm.2371 III. Rayner Rodriguez-Diaz, Robin Dando, Y. Anthony Huang, Per-Olof Berggren, Stephen D. Roper, Alejandro Caicedo (2011). Real time detection of acetylcholine release from the human endocrine pancreas. [Submitted]IV. Rayner Rodriguez-Diaz, Stephan Speier, Damaris Molano, Alexander L. Formoso, Itai Gans, Midhat Abdulreda, Over Cabrera, Alberto Fachado, Camillo Ricordi, Ingo Leibiger, Antonello Pileggi, Per-Olof Berggren, and Alejandro Caicedo (2011). A simple noninvasive system for investigating the role of innervation in pancreatic islet function in vivo. [Submitted]V. Daniel Nyqvist, Stephan Speier, Rayner Rodriguez-Diaz, R. Damaris Molano, Sasa Lipovsek, Marjam Rupnik, Andrea Dicker, Erwin Ilegems, Elsie Zahr-Akrawi, Judith Molina, Maitee Lopez-Cabeza M, Susana Villate, Midhat H. Abdulreda, Camilo Ricordi, Alejandro Caicedo, Pileggi, Per-Olof Berggren (2011). Donor islet endothelial cells in pancreatic islet revascularization. Diabetes. 60(10):2571-7. https://doi.org/10.2337/db10-1711 VI. Midhat H. Abdulreda, M, Gaetano Faleo, R. Damaris Molano, Judith Molina, Y. Tan, Ron Echeverria, Elsie Zahr-Akrawi, Rayner Rodriguez-Diaz, P. Edlund, Ingo Leibiger, Alisson L. Bayer, Victor L. Perez, Camilo Ricordi, Alejandro Caicedo, Antonello Pileggi, Per-Olof Berggren (2011). High resolution, non-invasive longitudinal live imaging of immune responses. Proc Natl Acad Sci U S A. 108(31):12863-8. https://doi.org/10.1073/pnas.1105002108 VII. Victor L. Perez, Alejandro Caicedo, Dora M. Berman, E. Arrieta, Midhat H. Abdulreda, Rayner Rodriguez-Diaz, Antonello Pileggi, E. Hernandez, S. R. Dubovy, Jean-Marie Parel, Camilo Ricordi, Norma M. Kenyon, Per-Olof Berggren (2011). The anterior chamber of the eye as a clinical transplantation site for the treatment of diabetes. Diabetologia. 54(5):1121-6. https://doi.org/10.1007/s00125-011-2091-y </p
LIFE-CYCLE PARAMETERS OF Copitarsia uncilata (LEPIDOPTERA: NOCTUIDAE) ON THREE NATURAL DIETS
No full textThis study describes the life cycle of Copitarsia uncilata Burgos & Leiva (Lepidoptera: Noctuidae) under laboratory conditions without photophase and a second experiment with photophase of 12 hours on three natural diets. The life cycle of C. uncilata was significantly shorter for females (76.46 ± 1.01 days, p=0.033) reared on alstroemeria (Alstroemeria sp.) diet without photophase, and for males (79.78 ± 0.36 days, p=0.046) reared on broccoli (Brassica oleracea italica), with photophase. The emergence of the adults was 100% and 80% from larvae fed on alstroemeria, 90.9% and 88.88% for individuals fed on broccoli, 86.2% and 50% for those fed on cauliflower (Brassica oleracea var. botrytis), without and with photophase respectively. The sex ratio (male:female) of individuals reared without photophase, evidenced a higher rate of females on alstroemeria (1:1.3), followed by cauliflower (1:0.6) and broccoli (1:0.5). In the experiment with photophase, the sex ratio was higher on alstroemeria (1:1.5), followed by cauliflower (1:0.9) and broccoli (1:0.6). As a conclusion, the most suitable diet for laboratory mass rearing in terms of life cycle parameters of C. uncilata is broccoli followed by alstroemeria and cauliflower
Estudio de un sistema Rfid para el control de inventarios y seguridad de muebles en Muebleria Caicedo
No full textEsta investigación detalla un estudio del sistema Identificación por radiofrecuencia (RFID) en
mueblería Caicedo, cuyo objetivo es dar a conocer los aspectos técnicos y el funcionamiento de
la tecnología, para lo cual se analizó y realizó los estudios necesarios para determinar el diseño
de un sistema RFID en las bodegas y salas de exhibición de los muebles, con esto facilitar la
gestión del inventario, además de evitar la constante pérdida y desubicación de los muebles. La
información que se presenta en este proyecto proviene de varias fuentes de investigación
especializadas en la tecnología RFID, para lo cual se logró detallar los principales usos, ventajas
y desventajas que se tiene de este sistema, además de mostrar las características técnicas que
deben de tener los equipos que se recomiendan para el diseño propuesto, y así contar con la
respectiva infraestructura tecnológica que se requiere en la mueblería. Identificación por
radiofrecuencia (RFID) es una de las tecnologías que ha logrado impactar por la eficiencia que
brinda en el área que sea implementada. Este sistema podrá lograr satisfacer las necesidades
tanto de los empleados que organizan los muebles, así como las existencias reales que necesita
visualizar el dueño del negocio, ya que resulta práctico contar con un equipo de fácil manejo
que ayudará a llevar un inventario más rápido, eficaz que logra detallar los datos de los muebles
con más efectividad, teniendo en cuenta la seguridad que se obtendrá. Con este diseño de sistema
se brindará un mejor control de entrada y salida de los productos terminados, así tener un
servicio seguro que se necesita para prevenir cualquier intento de hurtoThis research details a study of the Radio Frequency Identification (RFID) system in Caicedo
furniture, the objective of which is to publicize the technical aspects and operation of the
technology, for which the necessary studies were analyzed and carried out to determine the
design of an RFID system. in warehouses and furniture showrooms, thereby facilitating
inventory management, as well as avoiding the constant loss and dislocation of furniture. The
information presented in this project comes from various research sources specialized in RFID
technology, for which it was possible to detail the main uses, advantages and disadvantages of
this system, in addition to showing the technical characteristics that they must have. the
equipment that is recommended for the proposed design, and thus have the respective
technological infrastructure that is required in the furniture store. Radio frequency identification
(RFID) is one of the technologies that has made an impact due to the efficiency it provides in
the area that is implemented. This system will be able to satisfy the needs of both the employees
who organize the furniture, as well as the actual stocks that the business owner needs to see,
since it is practical to have an easy-to-use equipment that will help to carry an inventory faster,
more efficiently that manages to detail the furniture data more effectively, taking into account
the security that will be obtained. With this system design, a better control of entry and exit of
the finished products will be provided, thus having a secure service that is needed to prevent
any attempted theft
LIFE TABLE OF Orius insidiosus (HEMIPTERA: ANTHOCORIDAE) FEEDING ON Sitotroga cerealella (LEPIDOPTERA: GELECHIIDAE) EGSS
No full textTo use a natural enemy to control an insect pest, it is important to determine the biological parameters of the native populations of the predator. The goal of this study was determinate the biological parameters of O. insidiosus fed on Sitotroga cerealella eggs. A batch of 225 O. insidiosus eggs were laid into bean pods. The bean pods were kept in glass jars, and the eggs and first instar nymphs were counted daily. All nymphs were extracted and individualized in Petri dishes. The presence/absence of exuvie was observed daily as a way to assess the emergence of adults from the nymphal stage. Seventeen adult couples were placed into Petri dishes with a segment of bean pod. The bean pod segments were extracted and replaced daily, counting the number of eggs present on the pods. The life cycle, survival percentage, sex ratio, male/female longevity, pre ovoposition, ovoposition and post ovoposition periods were determined. Finally, fertility life table parameters were estimated. The nymphal development time was 12.0 ± 0.22 days, with 80.47 % ± 3.23 survival, while the total development time was 15.0 ± 0.23 days, with 66.67 % ± 1.90 survival. Of the total adults that emerged, 30.95 % ± 2.38 were females. The female sex ratio was 0.75, and the oviposition period was 0.86 ± 9.21 days with a total fertility of 60.29 ± 7.39 eggs. The data estimated from the fertility life table were: Ro: 28.26, rm: 0.14, T: 24.26, λ: 1.13 and DT: 5.01
Alternativa para los procesos logísticos de abastecimiento de mercancías de carga seca distribuida en vehículos de tipo c2 y c3 en la zona céntrica del municipio de Girardot-Cundinamarca
No full textSe analizó la situación actual del municipio de Girardot, donde el crecimiento de la población y de la infraestructura urbana han tenido cambios enormes, cabe resaltar que el potencial logístico del municipio puede ser explotado con el pasar de los años debido a su posibilidad de intermodalidad y su ubicación estratégica, que lo conecta con diferentes zonas del país y ciudades importantes donde el comercio y las industrias demandan grandes cantidades de productos a diario.
Luego de analizar los problemas asociados con la distribución urbana de mercancías en la zona céntrica del municipio de Girardot, que en su mayoría se realizada en vehículos cuyas codificaciones son de tipo C2 y C3 y teniendo en cuenta que la malla vial del municipio no se ha desarrollado siguiendo los lineamientos de algún tipo de planeación urbana, lo cual se refleja en el hecho de tener una infraestructura vial precaria e insuficiente, y fijándose adicionalmente, en el estado de sus vías, se puede notar un deficiente manejo y mantenimiento, teniendo en cuenta el estado actual de las vías y apoyados en los aspectos técnicos, poder plasmar una alternativa para ser aplicada y satisfacer las necesidades detectadas, para proceder con lo mencionado se comienza con la recopilación de información para seleccionar una opción de solución a los problemas de movilidad y distribución del municipio, pero fue necesario investigar más a fondo para lograr encontrar el origen de las cosas y sus beneficios, esto nos llevó a principios de la década de los 90s donde diversos países de Europa vieron la posibilidad de desarrollar alternativas que beneficiaran las problemáticas relacionadas a la logística de distribución urbana de mercancías, estás surgieron como resultado de diversas investigaciones y pruebas piloto desarrolladas en Alemania, Bélgica, Dinamarca, Países bajos y Suiza
EN TORNO A LA DIMENSIÓN LITERARIA DE VIENTO SECO
No full textThis article proposes three new interpretation keys in an approach to Viento seco by Daniel Caicedo: the emergence of poetic images in a prose dominated by stark realism, the chronological inversion of the central incidents and the complex structure of the novel. These aspects have been overlooked by criticism which, in general, has approached the novel with the preconception of its invalid literary value and testimonial importance. The analysis allows for the conclusion that the author, through these textual procedures, seeks not only the aesthetic dignity of his work, but also to draw the reader’s attention to that aspect.Este artículo propone tres claves de lectura nuevas para aproximarse a Viento seco de Daniel Caicedo: la irrupción de imágenes poéticas en una prosa dominada por el realismo descarnado, la inversión cronológica de los hechos centrales y la compleja estructura del relato. Estos aspectos han pasado inadvertidos para la crítica, que, en general, se ha aproximado a la novela con el prejuicio de su nulo valor literario y su importancia testimonial. El análisis permite concluir que el autor buscó a través de esos procedimientos textuales no solamente la dignidad estética de su obra, sino llamar la atención del lector sobre esa dimensión
CRITERIOS PARA LA PRODUCCIÓN DE Phytoseiulus persimilis (PARASITIFORMES: PHYTOSEIIDAE) BAJO CONDICIONES DE INVERNADERO
No full textEl ácaro depredador Phytoseiulus persimilis ha sido usado con éxito para el control del ácaro fitófago Tetranychus urticae, el cual constituye una de las plagas mas importantes en los cultivos de rosa de la Sabana de Bogotá. En Colombia esta estrategia de control se ha visto limitada por la falta de disponibilidad de los depredadores en el comercio del producto. En el presente trabajo se proponen criterios para estandarizar las bases para la producción de P. persimilis en plantas de frijol infestadas con poblaciones de T. urticae de diferentes tiempos de desarrollo, utilizando una proporción constante de depredadores liberados. Se encontró que plantas infestadas con poblaciones de T. urticae por más de tres semanas permiten obtener mayores incrementos de población de los depredadores y que aproximadamente a los 25 días después de realizada la liberación, de los depredadores en las plantas infestadas, se obtienen los mayores poblaciones del depredador en estado de ninfa y adulto para cosechar, y usar como estrategia de control en los cultivos
Damage Control for renal trauma: the more conservative the surgeon, better for the kidney
No full textUrologic trauma is frequently reported in patients with
penetrating trauma. Currently, the computerized tomography and
vascular approach through angiography/embolization are the
standard approaches for renal trauma. However, the management of
renal or urinary tract trauma in a patient with hemodynamic
instability and criteria for emergency laparotomy, is a topic of
discussion. This article presents the consensus of the Trauma
and Emergency Surgery Group (CTE) from Cali, for the management
of penetrating renal and urinary tract trauma through damage
control surgery. Intrasurgical perirenal hematoma
characteristics, such as if it is expanding or actively
bleeding, can be reference for deciding whether a conservative
approach with subsequent radiological studies is possible.
However, if there is evidence of severe kidney trauma, surgical
exploration is mandatory and entails a high probability of
requiring a nephrectomy. Urinary tract damage control should be
conservative and deferred, because this type of trauma does not
represent a risk in acute trauma management
PAUTAS PARA LA CONSTRUCCIÓN DE EDIFICACIONES CON PANEL SIMPLE EN EL TRÓPICO HÚMEDO: DISTRITO DE BUENAVENTURA
No full textEste proyecto investiga la viabilidad del sistema constructivo de paneles simples en el trópico húmedo de Buenaventura, Colombia, adaptándolo a condiciones climáticas locales, promoviendo prácticas sostenibles y evaluando su resistencia y seguridad sísmica para mejorar la calidad de vida y minimizar el impacto ambiental.This research project aims to evaluate the viability and effectiveness of the simple panel
construction system in the humid tropics, specifically in the District of Buenaventura and the
Colombian Pacific region. To achieve this, an exhaustive review of current construction guidelines
will be carried out to adapt and optimize this system to the climatic conditions of the area.
The characteristics and properties of the materials used will be analyzed, evaluating their resistance
and durability in tropical humid environments. Additionally, sustainable construction practices will
be promoted, encouraging the use of local and renewable materials, thus contributing to reducing
the environmental impact of buildings.
The project's focus is to ensure that constructions using simple panels are not only resistant and
efficient but also socially and environmentally sustainable in the long term. Compliance with current
construction regulations and codes will be ensured, guaranteeing the safety and legality of the
buildings.
Likewise, recommendations will be generated for the use of this system in the Pacific region, aiming
to provide construction alternatives that improve the quality of life and protect the heritage of the
inhabitants. It is essential that these constructions meet Colombian technical standards, including
seismic resistance requirements (NSR-10).
Finally, the performance of the simple panel has been analyzed in relation to the conditions of the
humid tropics, demonstrating its good performance. The research is supported by data from
international manufacturers and distributors, ensuring the accuracy of the information obtained.INTRODUCCIÓN
1. OBJETIVOS
1.1.OBJETIVO GENERAL
1.2.OBJETIVOS ESPECÍFICOS
2. PLANTEAMIENTO DEL PROBLEMA
2.1.ÁRBOL DEL PROBLEMA
3. JUSTIFICACIÓN
4. BASES TEORICAS
4.1. MARCO HISTÓRICO
4.1.1 Construcciones con panel simple en Colombia
4.1.1 Centro Comercial San Diego
4.1.2. Uso del panel simple estructural en el trópico húmedo
4.1.3. Normatividad en Colombia
4.1.4 Distribución y comercialización del panel simple estructural
4.2.MARCO REFERENTE
4.2.1 Referente Internacional
4.2.2 Referente nacional
4.2.3 Referente Valle del Cauca
4.3.MARCO TEÓRICO
4.3.1. Definición y características del panel estructural simple
4.3.2. Sistema modular
4.3.3. Sistemas livianos o ligeros
4.3.4. Sismorresistente
4.3.5. Sistema prefabricado
4.3.6. Partes del sistema
4.3.7. tipos de panel estructural
5. VENTAJAS Y DESVENTAJAS DE UTILIZAR EL PANEL ESTRUCTURAL SIMPLE
5.1. SISTEMA TRADICIONAL
5.1.1. Ventajas
5.1.2. Desventajas
5.2. SISTEMA PANEL SIMPLE
5.2.1 Ventajas
5.2.2 Desventaja
5.3. CONDICIONES CLIMÁTICAS DEL TRÓPICO HÚMEDO Y SU EFECTO EN LA
CONSTRUCCIÓN DE EDIFICACION 38
6. METODOLOGÍA DE INVESTIGACIÓN
6.1. RESULTADOS DE LA INVESTIGACIÓN
6.1.1. Características del clima tropical húmedo
6.1.2. Factores principales del clima
6.1.3. Humedad relativa del aire
6.1.4. Temperatura en la ciudad de buenaventura
6.1.5. Evaluación del impacto del clima sobre el panel simple estructural
6.2.ANÁLISIS DE RESULTADOS Y CONCLUSIONES
6.2.1. Análisis de resultados
6.2.2. Conclusiones
7. PAUTAS PARA EL DESARROLLO DE EDIFICACIONES EN EL TROPICO HUMEDO
7.1. PROCESO CONSTRUCTIVO
8. CONCLUSIONES Y RECOMENDACIONES
REFERENCIAS BIBLIOGRÁFICAPregradoArquitecto(a)Tecnología de la construcció
Parámetros del ciclo biológico de Copitarsia uncilata (Lepidoptera: Noctuidae) en tres dietas naturales
No full textThis study describes the life cycle of Copitarsia uncilata Burgos & Leiva (Lepidoptera: Noctuidae) under laboratory conditions without photophase and a second experiment with photophase of 12 hours on three natural diets. The life cycle of C. uncilata was significantly shorter for females (76.46 ± 1.01 days, p=0.033) reared on alstroemeria (Alstroemeria sp.) diet without photophase, and for males (79.78 ± 0.36 days, p=0.046) reared on broccoli (Brassica oleracea italica), with photophase. The emergence of the adults was 100% and 73.33% from larvae fed on alstroemeria, 90.9% and 88.88% for individuals fed on broccoli, 86.2% and 50% for those fed on cauliflower (Brassica oleracea var. botrytis), without and with photophase respectively. The sex ratio (male:female) of individuals reared without photophase, evidenced a higher rate of females on alstroemeria (1:1.3), followed by cauliflower (1:0.6) and broccoli (1:0.5). In the experiment with photophase, the sex ratio was higher on alstroemeria (1:1.5), followed by cauliflower (1:0.9) and broccoli (1:0.6). As a conclusion, the most suitable diet for laboratory mass rearing in terms of life cycle parameters of C. uncilata is broccoli followed by alstroemeria and cauliflower.Este estudio describe el ciclo biológico de Copitarsia uncilata Burgos & Leiva (Lepidoptera: Noctuidae) en condiciones de laboratorio, sin fotofase y 12 horas de fotofase, criado bajo tres dietas naturales. El ciclo de vida de C. uncilata fue significativamente más corto (76,46 ± 1,01 días, p=0,033) en hembras criadas en la dieta de alstroemeria (Alstroemeria sp.) sin fotofase, y el ciclo más corto (79,78 ± 0,36 días, p=0,046) en machos criados con broccoli (Brassica oleracea italica) con fotofase. La emergencia de los adultos fue 100% y 73.33% de larvas alimentadas con alstroemeria, 90,9% y 88,88% alimentadas con broccoli, 86,2% y 50% alimentadas con coliflor (Brassica oleracea var. botrytis), sin fotofase y con exposición a fotofase respectivamente. La proporción sexual (macho:hembra) de individuos sin fotofase, fue más alta en alstroemeria (1:1,3), seguido por coliflor (1:0.6) y broccoli (1:0,5). En el experimento con fotofase, la proporción sexual fue más alta en alstroemeria (1:1,5), seguido por coliflor (1:0,9) y broccoli (1:0,6). Como conclusión, la dieta más apropiada para cría en masa bajo condiciones de laboratorio en términos de los parámetros de ciclo biológico de C. uncilata es broccoli seguido por alstroemeria y coliflor
- …
