La incidencia del perfil del ingresante al magisterio en las anticipaciones y en la construcción de las teorías implícitas de los docentes de los institutos de formación : Estudio de caso de un Instituto de Formación Docente del sur del cono urbano bonaerense

El presente trabajo consiste en un estudio de caso de un instituto de formación respecto de la temática planteada en el trabajo. Para llevar a cabo tal investigación se recolectaron datos mediante encuestas a los alumnos ingresantes, observaciones etnográficas en los espacios de intercambio institucional, entrevistas a docentes y confrontación de esta información con lo elaborado en el marco teórico. Del análisis, confrontación y triangulación de los datos en cuestión fue posible arribar a las conclusiones que aquí se presentan.Tutora: Elsa CompagnucciFacultad de Humanidades y Ciencias de la Educació

Diversidad, abundancia y asociaciones de peces en el sistema lagunar de Sontecomapan, Veracruz México

Background. The Sontecomapan Lagoon is a protected natural area and is part of the Los Tuxtlas Biosphere Reserve on the south coast of the State of Veracruz, with significant fishing productivity and little ecological knowledge about its fish community. Objectives. Analyze space-time variations in diversity, richness, abundance, dominant species, community inhabitants, fish assemblages, and trophic groups. Methods. The fish collections were made between 2014 and 2020, in 10 stations with a trawl net. The sampling effort was validated using non-parametric estimators. Analysis of variance was used to indicate statistically significant differences in community ecological parameters between sites and months. Canonical correspondence analysis (ACC) was performed to determine species-habitat relationships. Results. Fifty species, 35 genera and 23 families were identified, with 2 new records, Chaetodipterus faber (Broussonet, 1782) and Pomadasys ramosus (Poey, 1860) and 2 dominant species, Diapterus rhombeus (Cuvier, 1829) and Cathorops aguadulce (Meek, 1904). The diversity values (H´ = 0.84 to 2.07, D = 2.36 to 3.83, J´= 0.26 to 0.64) and abundance (density = 0.009 to 0.035 ind./m2 , biomass = 0.105 to 0.044 g/m2 , average weight = 5.91 to 16.72 g/ind), are considered low compared to other similar coastal systems. The spatial and temporal fluctuations of these parameters are related to the life cycles of the species present and with the environmental dynamics of the system. The ACC analysis indicated that fish assemblages are determined by changes in salinity, transparency, and depth. Conclusion. The ecological information analyzed represents a broad frame of reference for a little-studied coastal area that requires management and conservation strategies for its biotic resources.Antecedentes. La Laguna de Sontecomapan es un Área Natural Protegida y forma parte de la Reserva de la Biosfera Los Tuxtlas en la costa sur del Estado de Veracruz, con productividad pesquera y escaso conocimiento ecológico sobre su comunidad de peces. Objetivos. Analizar las variaciones espacio temporales de diversidad, riqueza, abundancia, especies dominantes, componentes comunitarios, conjuntos de peces y grupos tróficos. Métodos. Las recolectas de los peces se realizaron entre 2014 y 2020, en 10 estaciones con una red de arrastre. El esfuerzo de muestreo se validó utilizando estimadores no-paramétricos. Se utilizó análisis de varianza para indicar diferencias estadísticas significativas de los parámetros ecológicos de la comunidad entre sitios y meses. Se realizó análisis de correspondencia canónica (ACC) para determinar las relaciones especie-hábitat. Resultados. Se identificaron 50 especies, 35 géneros y 23 familias, con 2 nuevos registros, Chaetodipterus faber (Broussonet, 1782) y Pomadasys ramosus (Poey, 1860) y 2 especies dominantes, Diapterus rhombeus (Cuvier, 1829) y Cathorops aguadulce (Meek, 1904). Los valores de diversidad (H´ = 0.84 a 2.07, D = 2.36 a 3.83, J´= 0.26 a 0.64) y abundancia (densidad = 0.009 a 0.035 ind./m2 , biomasa = 0.105 a 0.044 g/m2 , peso promedio = 5.91 a 16.72 g/ind), se consideran bajos comparados con otros sistemas similares. Las fluctuaciones espaciales y temporales de estos parámetros tienen relación con los ciclos de vida de las especies presentes y con la dinámica ambiental del sistema. El análisis ACC indicó que los conjuntos de peces están determinados por los cambios de salinidad, transparencia y profundidad. Conclusión. La información ecológica analizada representa un amplio marco de referencia para un área costera poco estudiada que requiere estrategias de manejo y conservación para sus recursos bióticos

Detección y clasificación de zero-day malware a través de data mining y machine learning

Dado el constante incremento, tanto en número como en complejidad, de los ataques informáticos, los mecanismos convencionales de detección resultan ineficientes en la mayoría de los escenarios. En este contexto, la presente investigación propone determinar si técnicas de data mining y machine learning pueden ser utilizadas efectivamente para el entrenamiento de algoritmos capaces de detectar y clasificar correctamente nuevos tipos de amenazas.Facultad de Informátic

Evaluación ecológica de las comunidades de peces en dos sistemas lagunares estuarinos del sur de Chiapas, México

In the Carretas-Pereyra and Chantuto-Panzacola systems, Chiapas, Mexico, was carried out studies of fish communities. In Chantuto-Panzacola system between March and November of 1997 a total of 1456 fish represented by 31 species were collected. In Carretas-Pereyra system between February and November of 1998, were collected a total of 3081 fish represented by 19 species. Each coastal lagoon has different values of diversity and abundance related to the environmental and biological characteristics of these estuarine systems. Carretas-Pereyra present its high community values in November and April with H´ = 1.8, D = 2.06, biomass = 0.89 g/m2, density = 0.30 ind/m2 and average weight = 4.99 g/ind. Chantuto-Panzacola present its high community values in March with H´ = 2.67, D = 3.89, biomass = 1.88 g/m2 , density = 0.25 ind/m2 and average weight = 7.55 g/ind. Significant differences (ANOVA and Tukey, p<0.05) were found between the ecological parameters and the environmental variables of both ecosystems in the months of study. The multiple discriminant analysis showed that salinity and dissolved oxygen were the most important factors in variation of the community of Carretas-Pereyra, while temperature and salinity were the most important factors in ChantutoPanzacola. The frequency analysis and spatial distribution of the fish allowed defining fish assemblages formed by several groups of species that inhabit these systems. Five species were defined as dominant for Carretas-Pereyra and nine for Chantuto-Panzacola, representing 72% and 71% in number and the 81% and 76.4% in weight of the total catch respectively. These species were Achirus mazatlanus, Atherinella guatemalensis, Caranx hippos, Cathorops fuerthi, Centropomus robalito, Cichlasoma macracanthum, Cichlasoma trimaculatum, Gobiomorus maculatus, Gobionellus microdon and Lile gracilis.En los sistemas lagunares costeros Carretas-Pereyra y Chantuto-Panzacola, Chiapas, México, fue realizado un estudio sobre aspectos ecológicos de las comunidades de peces. En Chantuto-Panzacola se recolectaron un total de 1,456 peces de 31 especies entre marzo y noviembre de 1997. En Carretas-Pereyra se colectaron un total de 3,081 peces, representados por 19 especies, entre febrero y noviembre de 1998. En cada laguna costera se observaron diferentes valores de diversidad y abundancia relacionados con las características ambientales y biológicas de estos sistemas. En Carretas-Pereyra los valores más altos se presentaron en noviembre y abril con H´ = 1.8, D = 2.06, biomasa 0.89 g/m2 , densidad 0.30 ind/m2 y peso promedio 4.99 g/ind. En Chantuto-Panzacola, los valores más altos se registraron en el mes de marzo con H´= 2.67, D = 3.89 sp/ind, biomasa 1.88 g/m2 , densidad 0.25 ind/m2 y peso promedio 7.55 g/ind. Se encontraron diferencias significativas (ANOVA y Tukey, p< 0.05) entre los parámetros ecológicos y las variables ambientales de ambos ecosistemas en los meses de estudio. El análisis discriminante múltiple, mostró que la salinidad y el oxígeno disuelto son los factores más importantes en la variación de la comunidad de Carretas-Pereyra, mientras que la temperatura y la salinidad son los factores más importantes en la comunidad de Chantuto-Panzacola. La frecuencia de aparición y distribución espacial de los peces, permitió definir conjuntos ictiofaunísticos formados por diferentes grupos de peces que habitan estos sistemas. Se definieron 5 especies dominantes en Carretas-Pereyra y 9 en Chantuto-Panzacola, representando el 72 % y 71 % en número y el 81% y 76% en peso de la captura total, respectivamente. Estas especies son Achirus mazatlanus, Atherinella guatemalensis, Caranx hippos, Cathorops fuerthi, Centropomus robalito, Cichlasoma macracanthum, Cichlasoma trimaculatum, Gobiomorus maculatus, Gobionellus microdon y Lile gracilis

Automatic segmentation of the spine by means of a probabilistic atlas with a special focus on ribs suppression

[EN] Purpose: The development of automatic and reliable algorithms for the detection and segmentation of the vertebrae are of great importance prior to any diagnostic task. However, an important problem found to accurately segment the vertebrae is the presence of the ribs in the thoracic region. To overcome this problem, a probabilistic atlas of the spine has been developed dealing with the proximity of other structures, with a special focus on ribs suppression. Methods: The data sets used consist of Computed Tomography images corresponding to 21 patients suffering from spinal metastases. Two methods have been combined to obtain the final result: firstly, an initial segmentation is performed using a fully automatic level-set method; secondly, to refine the initial segmentation, a 3D volume indicating the probability of each voxel of belonging to the spine has been developed. In this way, a probability map is generated and deformed to be adapted to each testing case. Results: To validate the improvement obtained after applying the atlas, the Dice coefficient (DSC), the Hausdorff distance (HD), and the mean surface-to-surface distance (MSD) were used. The results showed up an average of 10 mm of improvement accuracy in terms of HD, obtaining an overall final average of 15.51 2.74 mm. Also, a global value of 91.01 3.18% in terms of DSC and a MSD of 0.66 0.25 mm were obtained. The major improvement using the atlas was achieved in the thoracic region, as ribs were almost perfectly suppressed. Conclusion: The study demonstrated that the atlas is able to detect and appropriately eliminate the ribs while improving the segmentation accuracy.The authors thank the financial support of the Spanish Ministerio de Economia y Competitividad (MINECO) and FEDER funds under Grants TEC2012-33778 and BFU2015-64380-C2-2-R (D.M.) and DPI2013-4572-R (J.D., E.D.)Ruiz-España, S.; Domingo, J.; Díaz-Parra, A.; Dura, E.; D'ocon-Alcaniz, V.; Arana, E.; Moratal, D. (2017). 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IEEE Transactions on Biomedical Engineering, 60(1), 115-122. doi:10.1109/tbme.2012.2225833Forsberg, D., Lundström, C., Andersson, M., & Knutsson, H. (2013). Model-based registration for assessment of spinal deformities in idiopathic scoliosis. Physics in Medicine and Biology, 59(2), 311-326. doi:10.1088/0031-9155/59/2/311Yao, J., Burns, J. E., Forsberg, D., Seitel, A., Rasoulian, A., Abolmaesumi, P., … Li, S. (2016). A multi-center milestone study of clinical vertebral CT segmentation. Computerized Medical Imaging and Graphics, 49, 16-28. doi:10.1016/j.compmedimag.2015.12.006Shi, C., Wang, J., & Cheng, Y. (2015). Sparse Representation-Based Deformation Model for Atlas-Based Segmentation of Liver CT Images. Image and Graphics, 410-419. doi:10.1007/978-3-319-21969-1_36Domingo, J., Dura, E., Ayala, G., & Ruiz-España, S. (2015). Means of 2D and 3D Shapes and Their Application in Anatomical Atlas Building. 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Deserción en bachillerato y situación laboral: el caso de tres liceos cercanos a Montevideo.

Abstract. The aim of this paper is to analyze the views and hopes from students and principals involved in the final courses of high school in three schools near Montevideo (Solís de Mataojo, Tala, and Rincón de la Bolsa) about drop-out high rates; it attempts to distinguish the specific features that this phenomena acquires in these areas. We have entered into a field of study connected with the problems of these young people who drop out final courses of high school and early enter in different jobs (related to agricultural and livestock production and industry) following, in many cases, their family labor level and being drifted, maybe forever, from a possible postsecondary or university education.Resumen. El propósito de este trabajo es indagar acerca de las representaciones y expectativas que manejan estudiantes y directores vinculados al Bachillerato del Interior cercanos a Montevideo, en particular Solís de Mataojo, Tala y Rincón de la Bolsa, respecto a los altos índices de deserción intentando configurar las características específicas que el fenómeno adquiere en estos ámbitos. Hemos incursionado en un campo de investigación vinculado con la problemática de estos jóvenes que desertan del Bachillerato y se insertan tempranamente en diferentes puestos de trabajo (afines a la producción agropecuaria e industrial) siguiendo muchas veces el nivel de trabajo de sus familiares y que los aleja, quizás definitivamente, de una posible formación en estudios terciarios o universitarios

Deserción en bachillerato y situación laboral: el caso de tres liceos cercanos a Montevideo

El propósito de este trabajo es indagar acerca de las representaciones y expectativas que manejan estudiantes y directores vinculados al Bachillerato del Interior cercanos a Montevideo, en particular Solís de Mataojo, Tala y Rincón de la Bolsa, respecto a los altos índices de deserción intentando configurar las características específicas que el fenómeno adquiere en estos ámbitos. Hemos incursionado en un campo de investigación vinculado con la problemática de estos jóvenes que desertan del Bachillerato y se insertan tempranamente en diferentes puestos de trabajo (afines a la producción agropecuaria e industrial) siguiendo muchas veces el nivel de trabajo de sus familiares y que los aleja, quizás definitivamente, de una posible formación en estudios terciarios o universitario

Pulsed magnetic feld increases the efect of ultraviolet C radiation and thermal shock in aged yeasts

The study of the efects of the magnetic feld (MF) on living matter continues to be a dilemma. Until now, the interaction mechanisms of MF with living matter that explain the observed phenomena are unknown. Despite the existing literature and the multiple efects described to date, there are few published articles that study the combined efect of MF with other physical agents during the cellular aging process. In this sense, the aim of this work is to study whether low frequency and intensity pulsed and sinusoidal MF exposure produce alterations in the cell killing efect of ultraviolet C (UVC) radiation and thermal shock during the chronological aging of S. cerevisiae. Yeast cells were exposed to 2.45 mT (50 Hz) sinusoidal MF and 1.5 mT (25 Hz) pulsed MF, during 40 days of aging, in combination with UVC radiation (50 J/m2 ) and/or thermal shock (52°C). Cell survival was evaluated by clonogenic assay. The exposure of yeast to pulsed MF produces an acceleration of aging, which is not observed in cells exposed to sinusoidal MF. The pulsed MF modifes the cellular response to damaging agents only in aged S. cerevisiae cells. In this sense, the pulsed MF applied increases the damage induced by UVC radiation and by thermal shock. In contrast, the sinusoidal MF used has no efect.Funding for open access publishing: Universidad de Málaga/CBUA. This study was supported by the “Plan Andaluz de Investi gación, Desarrollo e Innovación (PAIDI); Junta de Andalucía”, code CTS-181

Caracterización anatomohisto-patológica de la placenta y correlación clínica en la enfermedad hipertensiva inducida por el embarazo en pacientes de Barranquilla (Colombia)

Resumen La enfermedad hipertensiva inducida por el embarazo (EHIE) es una de las causas más frecuentes de morbimortalidad materno-fetal. Se presenta en todas las poblaciones, con una incidencia general que varía entre el 5 y 7%. Este trabajo corresponde a un estudio descriptivo exploratorio de casos, aplicado a un grupo de pacientes que asistió a los servicios de maternidad de hospitales de Barranquilla en el período comprendido entre diciembre de 2003-junio de 2004, en el cual fue realizado un estudio de carácter clínico-anatomohistopatológico que comparó placentas de gestantes con diagnóstico clínico de preeclampsia con placentas controles. Las placentas fueron descritas en el hospital macroscópicamente siguiendo el protocolo de Bernischke y Driscol. Se realizaron 4 cortes de la placa corial, uno de la decidua, uno del rollo de membranas y uno del cordón umbilical, se fijaron en formol al 10%, incluidos en parafina y cortados a 6 micras y luego coloreados con hematoxilina-eosina, para su posterior análisis microscópico. Se concluyó que las alteraciones vasculares deciduales, el aumento del número de nódulos sinciciales, infartos, hemorragias, lesiones del circuito vascular-fetal, traducidas por necrosis hialina de la media de los vasos y presencia de células xantomatosas1 (aterosis aguda), son las alteraciones más sugestivas de la enfermedad hipertensiva del embarazo. Comprobando así lo descrito en la literatura. Palabras claves: Enfermedad hipertensiva inducida por el embarazo (EHIE), placenta, preeclampsia, embarazo. Abstract The hypertensive disease induced by the pregnancy (HDIP), is one of the most frequent causes of morbimortality materno-fetal. It presents displays on all the populations with a general in- cidence between 5 and 7 %. This work corresponds to an exploratory descriptive study of cases, applied to a group of patients that attended the services of maternity of hospitals in the period between December 2003 - June 2004, in which was made a analysis of character clinic-anatomohistopatologic which compare placentas of women with clinic diagnose of preeclampsia with placentas controls. The placents were described in hospital macroscopic following the protocol of Bernischke and Driscol next, they went including in formol to 10%. Cuts of plate corial, the decidua, the membrane roll were made and of the umbilical cord, they paid attention to formol to 10%, including in paraffin and cut to 6 microns and soon colored with hematoxilin-eosin, for its later analysis microscopic. This study demostrated alterations in the maternal fetal circuit, translated by hyaline necrosis of the average of the vases and the presence of xantomatosas cells (uteruses aged). Was observed proliferation of nodules sinciciales. The presence of fibrin of nitabuchi, deposits fibrinoides, infiltrated mononuclear, calcifications, thrombosis, necrosis fibrinode hyaline and hemorrhage endovascular profit to be observed as much in the placents cases as the controls but these were more significant in the cases. Injuries vascular cause hypoxia, which triggers events fisiopatolog- ics responsible for picture clinic. Key words: The hypertensive disease induced by the pregnancy (HDIP), placentas, preeclampsia, pregnancy