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Search Results: 1 - 10 of 210556 matches for " Hernán Hurtado Giraldo "
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Estudio preliminar morfológico y morfométrico de encéfalo del pez tiburoncito, Ariopsis seemanni, (Pisces: Ariidae)
Londo?o,Claudia; Hurtado Giraldo,Hernán;
Universitas Scientiarum , 2010,
Abstract: objective. to describe morphologically and morphometrically the encephalon of ariopsis seemanni. materials and methods. we worked with 10 juvenile specimens which were processed according to the ethical standards for handling fish. measurements of the total and standard length (cm) and weight (g) were taken for each individual. specimens were fixed in 4% formaldehyde. the encephalon was removed, the different regions were identified and the measurement of the different lobes was done, indicating their location, morphology, length and area using lateral, dorsal and ventral digitalized images that were measured with the scion image program. we calculated means and standard deviations, and obtained the percentage equivalence of each structure in relation to the entire encephalon. these data were then related to the habits of the species. results. we identified the olfactory bulbs, telencephalic hemispheres, optic lobes, cerebellum, among others. of the cranial nerves, only the optic nerve was observed. the largest structure of the encephalon is the cerebellum (44 ± 1.2% and 0.23 ± 0.03 cm2 area), followed by the telencephalic hemispheres (28 ± 0.57% and 0.13 ± 0.02 cm2 area). conclusions. the encephalon morphology of a. seemanni presented the general pattern of teleosts of the order siluriformes, with the cerebellum as the largest structure of the encephalon. based on the morphology and morphometry observed in the encephalon, we suggest that a. seemanni uses primarily vision and taste to explore the environment.
Estudio preliminar morfológico y morfométrico de encéfalo del pez tiburoncito, Ariopsis seemanni, (Pisces: Ariidae)
Claudia Londo?o,Hernán Hurtado Giraldo
Universitas Scientiarum , 2010,
Abstract: Preliminary morphologic and morphometric study of the encephalon of the tiburoncito Ariopsis seemanni (Pisces: Ariidae)Objective. To describe morphologically and morphometrically the encephalon of Ariopsis seemanni. Materials and methods. We workedwith 10 juvenile specimens which were processed according to the ethical standards for handling fish. Measurements of the total andstandard length (cm) and weight (g) were taken for each individual. Specimens were fixed in 4% formaldehyde. The encephalon wasremoved, the different regions were identified and the measurement of the different lobes was done, indicating their location, morphology,length and area using lateral, dorsal and ventral digitalized images that were measured with the Scion Image program. We calculated meansand standard deviations, and obtained the percentage equivalence of each structure in relation to the entire encephalon. These data were thenrelated to the habits of the species. Results. We identified the olfactory bulbs, telencephalic hemispheres, optic lobes, cerebellum, amongothers. Of the cranial nerves, only the optic nerve was observed. The largest structure of the encephalon is the cerebellum (44 ± 1.2% and0.23 ± 0.03 cm2 area), followed by the telencephalic hemispheres (28 ± 0.57% and 0.13 ± 0.02 cm2 area). Conclusions. The encephalonmorphology of A. seemanni presented the general pattern of teleosts of the order Siluriformes, with the cerebellum as the largest structureof the encephalon. Based on the morphology and morphometry observed in the encephalon, we suggest that A. seemanni uses primarilyvision and taste to explore the environment.
ESTUDIO HISTOLóGICO Y MORFOLóGICO PRELIMINAR DE LA HIPóFISIS DE ALEVINOS DE CACHAMA BLANCA, PIARACTUS BRACHYPOMUS (CUVIER) (CHARACIDAE)
Barrera-Bailón,Biviana; Caldas,María L; Hurtado-Giraldo,Hernán;
Actualidades Biológicas , 2008,
Abstract: piaractus brachypomus is a species of great economic importance in colombia. the purpose of this study is to accomplish an analysis at the histological and anatomical level of alevin pituitary of this species. we realized sagittal and transversal cuts of 5 and 7 μm of 20 alevin pituitaries for a histological and three-dimensional reconstruction studies. the pituitary of these specific alevins is located in the ventral zone of the brain, posterior to the optic chiasm, partially integrated by connective and nervous tissues between the nucleus tuberalis ventralis (tv) and hypotalamus periventriculares caudalis (hc). the pituitary contains basophils with large and non-centric nuclei, as well as chromophobes (c) with small nuclei and unstained cytoplasm. there is no presence of acidophils (a); however, blood flow reaches all parts of the pituitary. discrepancies between our study and that of literature are attributed to glandular immaturity.
Un sistema sencillo y de bajo costo para la reconstrucción tridimensional de estructuras embrionarias a partir de cortes seriados A Simple and Cheap 3D Reconstruction System of Embryonic Structures from Serial Sections
Suárez-Rairán Johanna,Córdoba-Parrado Laura,Hurtado-Giraldo Hernán
Acta Biológica Colombiana , 2007,
Abstract: En este trabajo se muestra el montaje y utilización de un sistema de reconstrucción tridimensional en estructuras embrionarias, utilizando equipos sencillos, de fácil adquisición y uso, utilizando como ejemplo la inervación del miembro posterior del embrión de rata de 19 días de gestación. Además, se muestra cómo pueden lograrse resultados de buen nivel, en cuanto a la forma, ubicación y distribución de las estructuras de interés, obteniendo adicionalmente información cuantitativa acerca de la forma y tama o (volumen y área superficial), a partir de la utilización de software gratuitos de libre acceso en internet. This work explaines how to setup and use a very cheap and simple 3D reconstruction system, for embryonic structures, using as an example the innervation of E19 hindlimb rat embryo. It also shows how results of good level can be achieved, such as, form, location and distribution of the structures of interest, obtaining additionally quantitative data of the size (volume and superficial area), and form. All the results mentioned above were obtained from the operation of free software available at the Internet.
Estudio Morfométrico del Nervio óptico de Tiburoncito (Ariopsis seemanni) Morphological Study of Tete Sea Catfish (Ariopsis seemanni) Optic Nerve
Diana Carolina Casta?eda Cortés,Oswaldo Tovar Bohórquez,Hernán Hurtado Giraldo
International Journal of Morphology , 2013,
Abstract: En peces, el nervio óptico es el encargado de transportar la información integrada por las células ganglionares de la retina hacia el tectum óptico, para que se generen imágenes acerca del entorno. El objetivo de este trabajo es describir morfométricamente el nervio óptico del tiburoncito (Ariopsis seemanni), para lo cual se utilizó la Microscopía óptica de Alta Resolución (MOAR), realizando cortes a 1 micra de espesor. El nervio óptico de A. seemanni presenta fibras mielínicas de diverso calibre, acompa adas de oligodendrocitos y astrocitos. El nervio está cubierto por las meninges, que presentan vasos sanguíneos y adipocitos. El nervio tiene un área total de 179604 ± 30163 μm2, diámetro de 478 ± 42 μm y un número total de fibras mielínicas de 22848 ± 4350, de las cuales la mayoría tiene un tama o peque o, que puede estar relacionado con una velocidad de conducción baja. The optic nerve carries out the information integrated by retinal ganglion cells towards the optic tectum, so that surrounding environment images are generated. The main goal of this paper is to describe morphometricaly the Tete sea catfish (Ariopsis seemanni) optic nerve, using high resolution optical microscopy (HROM), on 1 micron thick sections. A. seemanni optic nerve does present myelinated nerve fibers, accompanied by oligodendrocytes and astrocytes. The nerve is covered by the meninges, with blood vessels and adipocites. The nerve has a transversal area of 179,604 ± 30163 mm2, a diameter of 478 ± 42 mm and 22848 ± 4350 myelinated fibers, most are small in size, which may be related to a low conduction velocity.
COMPARACIóN HISTOLóGICA Y MORFOMéTRICA ENTRE EL OJO DE Eremophilus mutisii (TRICHOMYCTERIDAE) Y EL DE Oncorhynchus mykiss (SALMONIDAE)
TOVAR BOHóRQUEZ,MARIO OSWALDO; CONTRERAS BRAVO,LUISA FERNANDA; CALDAS,MARIA LEONOR; RODRíGUEZ CAICEDO,DANIEL; HURTADO GIRALDO,HERNáN;
Acta Biológica Colombiana , 2008,
Abstract: the importance of vision in fishes varies depending on their relationship to their habitat, being crucial for some species, and secondary for other species. the main goal of this work was to make a comparison between the eyes of capitán de la sabana and rainbow trout. the first one, from the cundiboyacense highlands, and the second one, a foreign species introduced in our country, very important as a cultured organism. histological 5 μm thickness eye sections were obtained. both species do present the typical teleosteal eye structure with an 8 layers retina, photoreceptor cells (cones and rods), as well as different types of neurons (bipolar, horizontal, amacrine, and ganglionic cells ), and an almost spherical lens. rainbow trout has cartilage in the sclerotica, while capitán de la sabana does not present this tissue. mean thickness of the structures in capitán de la sabana are: retina 183.5 41.2 μm, cornea 20.6 5.4 μm and iris 31.2 6.4 μm; mean thickness in rainbow trout are: retina 389.5 65.2 μm, cornea 300.4 101.8 μm, and iris 41.2 13.7 μm. our results shows thickness differences in retina, cornea, sclerotica, relative eye size, lenses diameter, being larger for rainbow trout. these differences are probably related to differences in sensibility and visual resolution between the species, and do reflect visual system adaptations to different environments.
Histología y morfometría de piel del pez Eremophilus mutisii (Trychomecteridae, Siluriformes)
Bonilla Lizarazo,Rocío Johanna; Quintero Virguez,Marllury; Gómez Ramírez,Edwin; Rodríguez Caicedo,Daniel; Hurtado Giraldo,Hernán;
Revista de Biología Tropical , 2008,
Abstract: skin histology and morphometry of the fish eremophilus mutisii (trychomecteridae, siluriformes). the tropical freshwater fish eremophylus mutisii is endemic to the cundinamarca highland in colombia. skin samples (0.5x0.5 cm2) were taken from 11 specimens at six body parts (mandible, dorsal head, dorsal trunk, caudal trunk, medial trunk and abdominal area), fixed in 4% formaldehyde, dehydrated in 95% ethanol and 99% isopropanol, embedded in paraffin and sectioned at 5 μm. the skin is made of two mayor cutaneous layers (epidermis and dermis) and a subcutaneous layer (hypodermis). the epidermis presents three layers with secretory cells, epithelial cells and a few taste buds; the dermis is separated from the epidermis by a basal membrane. we observed fibroblasts, two layers of melanophors and some blood vessels; the hypodermis has vascularized adipose tissue. skin thickness changes with body area; the dermis is thicker than the epidermis; skin has more club cells than mucous cells. the medial trunk area has the largest number of club and mucous cells. the skin of e. mutissi seems to mainly have a protective function. rev. biol. trop. 56 (2): 885-893. epub 2008 june 30.
Removal of Nonmyrmecochorous Seeds by Ants: Role of Ants in Cattle Grasslands
Selene Escobar-Ramírez,Sebastián Duque,Natalia Henao,Alejandra Hurtado-Giraldo,Inge Armbrecht
Psyche , 2012, DOI: 10.1155/2012/951029
Abstract: Livestock production models prevailing in Colombian Andes are simplified treeless pastures for extensive ranching, with the consequent reduction of environmental services, such as seed dispersal, due to lack of primary dispersers, scarcity of adequate sites for seedling establishment and competition with grasses. This study evaluated if, in these harsh environments, ants can promote the colonization of arboreal species through directed dispersion of seeds towards the nests. Ten seeds of each species were offered to ants in six grazing pastures. Ants removed 25% of the seeds (1827) in 48 hours. Preference for arillated and small-to-medium sized seeds, such as Pithecellobium dulce, and Guazuma ulmifolia, was observed. Cyphomyrmex major, Ectatomma ruidum, Solenopsis geminata and Atta cephalotes were the key ant species in seed removal. It was concluded that functional ant groups present in the pastures could contribute to secondary dispersion of seeds with potential for restoration.
CINéTICA ENZIMáTICA DE LA POLIFENOL OXIDASA DEL BANANO GROS MICHEL EN DIFERENTES ESTADOS DE MADURACIóN
GARCíA W.,Claudia L.; GIRALDO G.,Germán A.; HURTADO T.,Hernando; MENDIVIL,Carlos O.;
Vitae , 2006,
Abstract: the post harvest of banana is accompanied by multiple enzymatic reactions, which cause the degradation of starches and chlorophyll, the synthesis of sugars and carotenes, changes in the acidity, tissue softening and enzymatic browning. this browning is caused by the action of the polyphenoloxidase (ppo) on the phenols contained in the fruit and is considered an undesirable change by the consumer. to determine the time of minimum enzymatic activity in order to obtain its optimal processing, the variety gros michel was characterized in colour, texture, activity of water, humidity and brix degrees; then its enzyme kinetics were studied by measuring the formation of brown colour with an uv-visible spectrophotometer at 420nm. the amount of total protein (enzyme) was also quantified by the bradford method (reading at 595 nm). once the kinetics of each maturation stage were identified, a comparison was made among each of the groups by means of repeated measures analysis of variance, showing a marked and statistically significant difference among banana of young and old maturation stages in a decreasing manner, finding the minimum point of activity of the enzyme in the most advanced maturation stages.
CINéTICA ENZIMáTICA DE LA POLIFENOL OXIDASA DEL BANANO GROS MICHEL EN DIFERENTES ESTADOS DE MADURACIóN ENZYME KINETICS OF POLYPHENOL OXIDASE FROM GROS MICHEL BANANA THROUGH DIFFERENT MATURATION STAGES
Claudia L. GARCíA W.,Germán A. GIRALDO G.,Hernando HURTADO T.,Carlos O. MENDIVIL
Vitae , 2006,
Abstract: La postcosecha del banano se acompa a de múltiples reacciones enzimáticas, causantes de la degradación de almidones y clorofila, de la síntesis de azúcares y carotenos, y de los cambios en la acidez, ablandamiento de tejidos y pardeamiento enzimático. Este pardeamiento es causado por la acción de la Polifenol Oxidasa (PFO) sobre los fenoles contenidos en el fruto y es considerado un cambio indeseable por el consumidor. Con el objeto de determinar el momento de mínima actividad enzimática para lograr su óptimo procesamiento, se caracterizó la variedad Gros Michel en diferentes estados de maduración, en cuanto a su color, textura, actividad de agua, humedad y grados Brix, y luego se midió la cinética enzimática, aprovechando la formación del color café durante el pardeamiento, empleando un espectrofotómetro de UV-visible a 420nm. También se cuantificó la cantidad de proteína (enzima) mediante el método de Bradford (lectura a 595nm). Una vez identificadas las cinéticas de cada estado de maduración, se hizo una comparación entre cada uno de los grupos mediante la técnica estadística de Análisis de Varianza con Medidas Repetidas en el tiempo, que mostró una marcada diferencia, estadísticamente significativa, entre los bananos de menor y mayor estado de maduración en forma decreciente, y se encontró el punto mínimo de actividad de la enzima en los estados más avanzados de maduración. The post harvest of banana is accompanied by multiple enzymatic reactions, which cause the degradation of starches and chlorophyll, the synthesis of sugars and carotenes, changes in the acidity, tissue softening and enzymatic browning. This browning is caused by the action of the Polyphenoloxidase (PPO) on the phenols contained in the fruit and is considered an undesirable change by the consumer. To determine the time of minimum enzymatic activity in order to obtain its optimal processing, the variety Gros Michel was characterized in colour, texture, activity of water, humidity and Brix degrees; then its enzyme kinetics were studied by measuring the formation of brown colour with an UV-visible spectrophotometer at 420nm. The amount of total protein (enzyme) was also quantified by the Bradford method (reading at 595 nm). Once the kinetics of each maturation stage were identified, a comparison was made among each of the groups by means of Repeated Measures Analysis of Variance, showing a marked and statistically significant difference among banana of young and old maturation stages in a decreasing manner, finding the minimum point of activity of the enzyme in the most advanced matu
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