Una experiencia de sistematización y análisis de unidades didácticas elaboradas por estudiantes para profesores de matemáticas de la Universidad Distrital Francisco José de Caldas

En el trabajo desarrollado se generara un proceso de sistematización mediante la recolección de unidades didácticas de estudiantes pertenecientes al proyecto curricular de la Licenciatura en Educación básica con Énfasis en Matemáticas, de la universidad distrital francisco José de Caldas, específicamente estudiantes que han cursado la asignatura: practica intermedia III Gestión, en los periodos comprendidos entre 2004-1 y 2009-3, para así establecer un análisis de sus elementos constitutivos. Este proceso se llevara a cabo destacando en aquellas unidades solamente las guías del profesor propuestas para el desarrollo de las secuencias. En cuanto al establecimiento de la metodología se ha decidido adoptar para la consecución de los objetivos una metodología cualitativa de naturaleza descriptiva, en donde el análisis de contenido es la técnica a usar en la sistematización de unidades didácticas

Endoplasmic Reticulum–Mitochondria Calcium Communication and the Regulation of Mitochondrial Metabolism in Cancer: A Novel Potential Target

Cancer is characterized by an uncontrolled cell proliferation rate even under low nutrient availability, which is sustained by a metabolic reprograming now recognized as a hallmark of cancer. Warburg was the first to establish the relationship between cancer and mitochondria; however, he interpreted enhanced aerobic glycolysis as mitochondrial dysfunction. Today it is accepted that many cancer cell types need fully functional mitochondria to maintain their homeostasis. Calcium (Ca2+)—a key regulator of several cellular processes—has proven to be essential for mitochondrial metabolism. Inositol 1,4,5-trisphosphate receptor (IP3R)-mediated Ca2+ transfer from the endoplasmic reticulum to the mitochondria through the mitochondrial calcium uniporter (MCU) proves to be essential for the maintenance of mitochondrial function and cellular energy balance. Both IP3R and MCU are overexpressed in several cancer cell types, and the inhibition of the Ca2+ communication between these two organelles causes proliferation arrest, migration decrease, and cell death through mechanisms that are not fully understood. In this review, we summarize and analyze the current findings in this area, emphasizing the critical role of Ca2+ and mitochondrial metabolism in cancer and its potential as a novel therapeutic target

Análisis de los elementos constitutivos como configuradores de la guía del profesor dispuestos en algunas unidades didácticas: el caso de la práctica III en la Licenciatura en Educación Básica con Énfasis en Matemáticas

La Licenciatura en Educación Básica con Énfasis en Matemáticas, de la Universidad Distrital Francisco José de Caldas, concibe la práctica docente como el espacio de formación en el que los estudiantes para profesores de matemáticas participan en interacciones que permitan reflexionar y abordar situaciones propias de su futura labor profesional, la cual implica la construcción de su conocimiento profesional explicitando sus concepciones, expectativas, negociando nuevos significados y la posibilidad de ir integrando paulatinamente herramientas conceptuales que les permitan una observación del medio sobre el cual gira la enseñanza de las matemáticas escolares. El trabajo desarrollado está basado en la caracterización de sus acciones plasmadas en los diseños de las guías del profesor, consignadas en las unidades didácticas de la práctica intermedia III

The Mitochondrial Complex(I)ty of Cancer

Recent evidence highlights that the cancer cell energy requirements vary greatly from normal cells and that cancer cells exhibit different metabolic phenotypes with variable participation of both glycolysis and oxidative phosphorylation. NADH–ubiquinone oxidoreductase (Complex I) is the largest complex of the mitochondrial electron transport chain and contributes about 40% of the proton motive force required for mitochondrial ATP synthesis. In addition, Complex I plays an essential role in biosynthesis and redox control during proliferation, resistance to cell death, and metastasis of cancer cells. Although knowledge about the structure and assembly of Complex I is increasing, information about the role of Complex I subunits in tumorigenesis is scarce and contradictory. Several small molecule inhibitors of Complex I have been described as selective anticancer agents; however, pharmacologic and genetic interventions on Complex I have also shown pro-tumorigenic actions, involving different cellular signaling. Here, we discuss the role of Complex I in tumorigenesis, focusing on the specific participation of Complex I subunits in proliferation and metastasis of cancer cells

The Computers and Networking in Colombia: A Possibility of Globalized Interaction on Public Educational Institutions and Regional Development

En el presente artículo se presentarán varios apartados que permiten comprender los procesos educativos que se dan a través de las interacciones entre sujeto-computador. En este orden, se reportan algunos elementos, propuestas, programas y estudios internacionales (como los de UNESCO) y otros nacionales (COMPARTEL y Computadores para Educar), para puntualizar en un caso de los procesos de acompañamiento de docentes, en áreas rurales de Colombia, a través del empleo del computador y la red.This article will be presented several sections that provide insights into educational processes that occur through interactions between subject and computer. In this connection, some elements, proposals, programs and international studies (such as UNESCO) and national (COMPARTEL and Computadores para Educar) are reported, to specify in a case of accompanying processes of teachers in rural areas of Colombia through the use of computer and network

Acute responses of blood pressure, heart rate and rating of perceived exertion in hypertensive patients

Objetivo: Medir y comparar el comportamiento agudo de la presión arterial (TA), la frecuencia cardiaca (FC) y la percepción subjetiva del esfuerzo físico (PSE) durante un circuito de pesas de resistencia variable (CRV) versus ejercicio aeróbico submáximo en cicloergómetro (EA) en hipertensos estados I y II.Métodos: Se evaluaron 21 individuos (8 hombres y 13 mujeres) hipertensos controlados de estados I y II (15 activos y 6 sedentarios, 56±5.9 años). Todos recibieron inducción sobre calentamiento, manejo de escala de PSE, técnica respiratoria y uso de máquinas de pesas durante el ejercicio. Con intervalos de una semana se sometieron a una sesión de CRV en seis estaciones al 50% de 1RM, y a una sesión de EA a intensidades de 70%-80% de la FCmax, en intervalos de una semana. Durante ambas sesiones se realizaron mediciones de FC, PA y PSE.Resultados: Se aplicó una Prueba t pareada para comparar las respuestas a ambos tipos de ejercicio. Se encontró un incremento menor de la FC (p0.05).Conclusión: El estudio evidenció que la respuesta cardiovascular aguda y la PSE de hipertensos durante un CRV fueron similares a las observadas con EA. Se observó que la respuesta presora al circuito de pesas fue menor en pacientes con entrenamiento aeróbico previo.Objective: To assess and compare acute responses in arterial blood pressure (BP), heart rate (HR) and rating of perceived exertion scale (PES) during a variable-resistance weight-lifting circuit (WC) versus submaximal aerobic exercise in cycloergometer (AE) in individuals with hypertension scaled I and II. Methods: 21 subjects with controlled hypertension scaled I and II (8 males and 13 females, 15 actives and 6 sedentary, age 56±5.9 years) were evaluated. All the participants received training about warm-up, use of PES, and respiratory and weight lifting machines techniques in exercise. All underwent a single session of WC in six stations at 50% 1RM and a single session of AE at 70%-80% FCmax, in intervals of one week. BP, HR and PES was measured in both exercises. Results: To compare responses in both types of exercise, at Test was used. It found a lower response of HR (p<0.001), systolic BP (p<0.005) and PES (p<0.005) during WC. Greater diastolic BP response was found in WC, although it was not significative (p=0.139). Sedentary subjects showed greater increases. Responses of variables were similar between stations in WC. Conclusion: This study evidenced a similar behavior of acute cardiovascular responses and PES during WC versus AE in hypertensive subjects. It showed a lower pressure response during WC in subjects with previous aerobic training

Stable Sampling Equilibrium in Common Pool Resource Games

This paper reconsiders evidence from experimental common pool resource games from the perspective of a model of payoff sampling. Despite being parameter-free, the model is able to replicate some striking features of the data, including single-peaked frequency distributions, the persistent use of strictly dominated actionsand stable heterogeneity in choices. These properties can also be accurately replicated using logit quantal response equilibrium (QRE), but only by tuning the free parameter separately for separate games. When the QRE parameter is constrained to be the same across games, sampling equilibrium provides a superior fit to the data. We argue that these findings are likely to generalize to other complex games with multiple players and strategies

Interactions Between Sponges and Macroalgae on Temperate Rocky Reefs

Changes in the distributions of organisms not only alter community composition and food web structure, but also can initiate important changes at the ecosystem level. Understanding the interactions between biotic and abiotic factors affecting species’ distribution patterns in temperate habitats is important for predicting responses to future environmental change. Sponges are important members of temperate rocky reefs assemblages that are influenced by a number of abiotic factors including water movement, light regime, inclination and stability of the substratum, as well as complex ecological interactions. The aim of this thesis was to investigate the interactions between sponges and macroalgae on shallow-water rocky reefs of Wellington, New Zealand, assessing if the distribution patterns of sponges are independent of algal populations. I used a combination of surveys, and manipulative field and laboratory experiments to explore the existence of interactions (positive or negative) between sponges and macroalgae and also to explore the effect of environmental factors on the distribution and abundance of temperate sponges. My first objective was to determine if the spatial distribution patterns of sponges are independent of macroalgae distribution and abundance at different sites on the Wellington south coast (Chapter 2). The results showed that abundance of most sponge species were strongly correlated with inclination, which supports previous studies in the northern hemisphere suggesting that sponge abundance and algal abundance are negatively correlated. In contrast, only a few sponge species were positively correlated with algal abundance. I then explored the positive interactions occurring between some sponges species and the presence of canopy-forming algae (Chapter 3). Results from this chapter suggest the canopy of Ecklonia radiata facilitates the existence of some sponge species such as Crella incrustans on vertical rocky walls. The removal of Ecklonia canopy led to a community dominated by turf algae, which corresponded with a decrease in sponge abundance and richness. My results suggest that the Ecklonia canopy facilitates the presence of some sponge species and allows their coexistence with turf algae underneath the canopy and also by altering immediate physical factors that may be detrimental for some sponge species. To further explore the existence of sponges and understory algae, I used an experimental approach (Chapter 4) to investigate the effect of the brown alga Zonaria turneriana on Leucetta sp. and also mechanisms involved in the interactions. However results from this chapter provided no evidence to support previous hypotheses that understory algae negatively affect sponges. In the last data chapter (Chapter 5), I studied sponges inhabiting different habitats in order to test if environmental variation affects the abundance and diversity of microorganisms, hence having the potential to affect the distribution and abundance of these species The stability observed in bacterial communities among specimens occupying different habitats suggests that environmental variation occurring in those habitats does not affect the stability of the community, and hence most likely does not radically alter the metabolism of these sponges. Although environmental factors such as light and sediment may have an effect on early sponge stages, other environmental (e.g. nutrients, temperature, wave action) and biotic factors, are more likely to influence the growth, survival and distribution of sponges on temperate rocky reefs. In summary, temperate sponge assemblages are strongly influenced by interactions between a number of abiotic and biotic factors. The outcomes of the ecological interactions are controlled by environment (e.g. influence of inclination on competition between sponges and understory algae) and at the same time, biological interactions (e.g. facilitation) can moderate the influence of abiotic factors such as light, sedimentation and wave action, thus facilitating the coexistence between sponge and macroalgae underneath the Ecklonia canopy. My thesis makes a significant contribution to our knowledge of temperate subtidal ecology, in terms of the effects of biotic and abiotic factors on sponge assemblages and also improves our knowledge of temperate patterns of sponge and macroalgal interactions. Finally, my thesis highlights the importance of small-scale environmental variation in influencing the structure and diversity of sponge assemblages and also increase our understanding of temperate rocky reefs sponges, especially on the less studied sponge assemblages occurring in Ecklonia stands on vertical rocky walls

The role of mental workload in sport training planning

One of the keys to achieving success in training is the correct alternation between exertion and rest. Accumulation of load causes fatigue, with a consequent deterioration of an athlete’s motor skills. This impact on the organism depends on the capacity of the athlete to adapt to the stimuli that generated it. Repetitive loads, systematically above the adaptive capacity of the athlete, can produce performance and mode deterioration in the form of dysfunctional overtraining or stalement. (Goodger, Gorely, Lavallee AND Harwood, 2007; Gould, 1996; Gould AND Dieffenbach, 2002; Kellmann, 2002). Loading stimuli can be physical and/or mental. Although the impact of the former has been widely studied, this is not the case with the latter. Therefore, our aim was (1) to review the concept of mental workload, including cognitive and emotional elements, (2) to explore the implications of controlling mental workload for training, and (3) to propose practical applications for designing training task

El papel de la carga mental en la planificación del entrenamiento deportivo

Una de las claves que determinan el éxito del entrenamiento es la alternancia correcta entre esfuerzo y descanso. La acumulación de esfuerzo puede producir fatiga, con el consiguiente deterioro de la capacidad motriz del deportista. Su impacto a largo plazo sobre el organismo depende de la capacidad adaptativa del deportista ante los estímulos que la generaron. El sometimiento a cargas por encima de la capacidad adaptativa del deportista produce un estado de incapacidad funcional conocido con el término "sobreentrenamiento" y caracterizado por la pérdida de rendimiento y alteraciones emocionales (Goodger, Gorely, Lavallee y Harwood, 2007; Gould, 1996; Gould, y Dieffenbach, 2002; Kellmann, 2002). Los estímulos que determinan la carga del entrenamiento son de naturaleza física y mental. Aunque la repercusión de los primeros ha sido ampliamente estudiada, no sucede igual con la de los segundos. Por tanto, nuestro objetivo es (1) revisar el concepto de carga mental, incluyendo elementos de carga cognitiva y emocional; (2) profundizar en las repercusiones de la carga mental y la necesidad de controlarla en el entrenamiento, y (3) proponer aplicaciones para el diseño de tareas por parte del entrenador.One of the keys to achieving success in training is the correct alternation between exertion and rest. Accumulation of load causes fatigue, with a consequent deterioration of an athlete's motor skills. This impact on the organism depends on the capacity of the athlete to adapt to the stimuli that generated it. Repetitive loads, systematically above the adaptive capacity of the athlete, can produce performance and mode deterioration in the form of dysfunctional overtraining or stalement. (Goodger, Gorely, Lavallee AND Harwood, 2007; Gould, 1996; Gould and Dieffenbach, 2002; Kellmann, 2002). Loading stimuli can be physical and/or mental. Although the impact of the former has been widely studied, this is not the case with the latter. Therefore, our aim was (1) to review the concept of mental workload, including cognitive and emotional elements, (2) to explore the implications of controlling mental workload for training, and (3) to propose practical applications for designing training tasks.Uma das chaves que determinam o êxito do treino é a alternância correcta entre esforço e descanso. A acumulação de esforço pode produzir fadiga, com o consequente deterioramento da capacidade motora do atleta. O seu impacto a longo prazo sobre o organismo depende da capacidade adaptativa do desportista face aos estímulos que a originam. A exposição a cargas acima da capacidade adaptativa do atleta produz um estado de incapacidade funcional denominado de "sobretreino" e caracterizado pela perda de rendimento e alterações emocionais (Goodger, Gorely, Lavallee e Harwood, 2007; Gould, 1996; Gould e Dieffenbach, 2002; Kellmann, 2002). Os estímulos que determinam a carga de treino são de natureza física e mental. Embora a repercussão dos primeiros tenha sido amplamente estudada, o mesmo não sucede com os segundos. Como tal, o nosso objectivo é (1) rever o conceito de carga mental, incluindo elementos de carga cognitiva e emocional; (2) aprofundar as repercussões da carga mental e a necessidade de controlá-la no treino, e (3) propor aplicações para o delineamento de tarefas por parte do treinador