Curriculum project as a key instrument for the development of the teaching/learning process in mathematics

El presente artículo expresa nuestra opinión sobre el proyecto curricular en Matemáticas, intentando llenar un vacío existente y haciendo unas sugerencias que esperamos sean útiles a los profesores. Se estudian los modelos subyacentes (actual y de la reforma), y, a partir de lo anterior, se efectúa una propuesta de proyecto curricular en Matemáticas. Se pretende proporcionar una fundamentación teórica en la que un profesor pueda apoyarse para realizar sus Proyectos curriculares relativos al área de Matemáticas; sugerir un posible esquema que puede servirle de pauta al profesor en los proyectos curriculares que tenga que realizar es este área y dar pautas para valorar un proyecto curricular del área de Matemáticas. Se indican los errores más frecuentes que se suelen cometer, con el fin de los profesores no vayan a caer en ellos en los proyectos que elaboren en el futuro, y por último se ofrece una bibliografía concisa, pero suficiente, para que el profesor disponga de los referentes adecuados para abordar su propio desarrollo curricular.The present article expresses our opinion on the curriculum project in mathematics, aiming to fill an existent gap and making suggestions which we hope will be useful for the teacher. The underlying models (actual and reformed) are studied and from them a proposal for a curriculum project in mathematics is made. The intention is: to supply a theoretical foundation on which the teacher can learn to carry out his curriculum projects relative to the area of mathematics: to suggest a possible scheme which can serve as a model for the teacher in the curriculum projects to be carried out in this area and to give-lines for evaluating a curriculum project in mathematics. The most frequent errors committed are indicated so that the teacher does not fall into then in the projects he elaborates in the future and finally a concise, but sufficient, bibliography is offered so that the teacher has at his disposal the adequate references for carrying out his own curriculum development.peerReviewe

Quantum Interferences in the photodissociation of Cl2(B) in superfluid helium nanodroplets (4He)N

Quantum interferences are probably one of the most fascinating phenomena in chemical physics and, particularly, in reaction dynamics, where they are often very elusive from an experimental perspective. Here, we have theoretically investigated, using a hybrid method recently proposed by us, the dynamics of the formation of confinement quantum interferences in the photodissociation of a Cl2 molecule (B ← X electronic excitation) embedded in a superfluid helium nanodroplet of different sizes (50-500 4He atoms), which is to the best of our knowledge the first time that this type of interference is described in reaction dynamics. Thus, we have widely extended a recent contribution of our group, where interferences were not the main target, identifying the way they are formed and lead to the production of strongly oscillating velocity distributions in the Cl dissociating atoms, and also paying attention to the energy transfer processes involved. This probably corresponds to a rather general behavior in the photodissociation of molecules in helium nanodroplets. We hope that the present study will encourage the experimentalists to investigate this captivating phenomenon, although the technical difficulties involved are very high

Detecting paraprotein interference on a direct bilirubin assay by reviewing the photometric reaction data

The direct bilirubin (D-Bil) assay on the AU Beckman Coulter instrumentation can be interfered by paraproteins, which may result in spurious D-Bil results. In a previous work, we took advantage of this fact to detect this interference, thus helping with the identification of patients with unsuspected monoclonal gammopathies. In this work, we investigate the possibility to detect interference based on the review of the photometric reactions, regardless of the D-Bil result. The D-Bil assay was carried out in a set of 2164 samples. It included a group of 164 samples with paraproteins (67 of which caused interference on the assay), as well as different groups of samples for which high absorbance background readings could also be expected (i.e. hemolyzed, lipemic, or icteric samples). Photometric reaction data were reviewed and receiver operating characteristics (ROC) curves were used to establish a cut-off for absorbance that best discriminates interference. The best cut-off was 0.0100 for the absorbance at the first photometric point of the complementary wavelength in the blank cuvette. Once the optimal cut-off for probable interference was selected, all samples analyzed in our laboratory that provided absorbance values above this cut-off were further investigated to try to discover paraproteins. During a period of 6 months, we detected 44 samples containing paraproteins, five of which belonged to patients with non-diagnosed monoclonal gammopathies. Review of the photometric reaction data permits the systematic detection of paraprotein interference on the D-Bil AU assay, even for samples for which reasonable results are obtained

Aportaciones sobre la implantación del Plan Bolonia. Un giro copernicano para los alumnos

La implantación del Sistema del denominado Plan Bolonia no sólo representa un reto para el profesorado sino también para el alumnado, acostumbrado a seguir la clase de lejos, participar poco en ella y darse un atracón de estudiar los días previos al examen. Un sistema basado en la asistencia a clase de forma activa, haciendo ejercicios y trabajos en grupo asiduamente, representa para muchos de nuestros alumnos un giro copernicano. En este trabajo se presenta el seguimiento de una cierta evaluación continua en una asignatura que aunque está situada en 2º curso es específica de los estudios que nos ocupa de la Ingeniería Naval, lo que podría dar lugar a pensar un cierto interés o al menos motivación por parte del alumno. Una vez planteada la metodología de la evaluación continua, se analizan la participación de los alumnos, su asistencia a clase, la evolución de los abandonos y la influencia de este sistema en los resultados académicos. Los resultados pondrán de manifiesto las dificultades que la implantación del Plan Bolonia tiene entre el alumnado acostumbrado a otros esquemas de funcionamiento

DESARROLLO RURAL Y PALMA DE ACEITE. ESTUDIO DE CASO EN CAMPECHE, MÉXICO

El cultivo de palma de aceite ha crecido rápidamente en Campeche en los últimos años bajo un modelo de plantaciones campesinas a pequeña escala y se planifica convertir al estado en el principal productor de aceite de palma de México. El territorio de Campeche tiene un alto grado de conservación biológica y la expansión de la palma de aceite es motivo de controversia por sus impactos ambientales y sociales. Se presenta el estudio de caso del ejido Independencia para conocer desde la perspectiva de los campesinos los impactos generados por las plantaciones de palma de aceite. Los campesinos tienen una visión positiva sobre la palma de aceite como fuente de ingresos y empleo para los palmicultores, pero no perciben que haya mejorado las condiciones de vida de la comunidad. Los campesinos reconocen beneficios ambientales asociados a las plantaciones de palma de aceite como la reforestación de sus parcelas y la recuperación de la biodiversidad

Modeling and maps generation from the spatial behavior of Sporisorium reilianum ((Kühn) Langdon y Fullerton) in Mexico State, México

El presente estudio se realizó con la finalidad de modelizar la distribución espacial del carbón de la espiga del maíz causada por Sporisorium reilianum durante 2006 en el Estado de México y su visualización a través de la generación mapas de densidad. El muestreo se realizó en 100 parcelas georreferenciadas por cada localidad analizada. La incidencia de la enfermedad (porcentaje de plantas enfermas) se determinó al establecer cinco puntos parcela, en cada punto se contabilizaron 100 plantas. Se realizó el análisis geoestadístico para estimar el semivariograma experimental, una vez obtenido, se ajustó a un modelo teórico (esférico, exponencial o gaussiano) a través de los programas Variowin 2.2., su ajuste se validó a través de la validación cruzada. Posteriormente, se elaboraron mapas de agregación de la enfermedad con el método de interpolación geoestadística o krigeado. Los resultados indicaron que la enfermedad se presentó en 20 localidades de 19 municipios del Estado de México; todas las localidades presentaron un comportamiento espacial agregado de la enfermedad, 16 localidades se ajustaron al modelo esférico, dos al modelo exponencial y dos localidades se ajustaron al modelo gaussiano. En todos los modelos se lograron establecer mapas de agregación que permitirá adecuar las acciones de manejo en términos de puntos o sitios específicos.This study was done with the purpose of modeling the spatial distribution of the head smut in maize, caused by the Sporisorium reilianum in 2006 in the Mexico State, and its visualization through the elaboration of density maps. The sampling was made in 100 parcels, which were georeferenced by location. The incidence of the disease was by establishing five points in each plot of maize. In each point 100 plants were counted by row. The plants with symptoms of this disease were registered. A geoestatistic analysis was done to estimate the experimental semivariograms once done; it was adjusted to a theoretical model (Spherical, exponential o Gaussian) through the VarioWin 2.2 program. Its adjustment was proved through the crossed validation. Subsequently aggregation maps of the disease were done through the geostatistic interpolation method or kriging. The results show that the disease was presented in 20 locations in 19 counties in the State of Mexico. All the locations presented a cluster spatial behavior of this disease. Moreover 16 locations were adjusted to the spherical model, two the exponential model and another two to the Gaussian model. In all models it was achieved to establish aggregation mapswhich will allow to adequate the management actionin the required points.Fil: Ramírez, José Francisco. Universidad Autónoma del Estado de México. Facultad de Ciencias AgrícolasFil: González, Andrés. Universidad Autónoma del Estado de México. Facultad de Ciencias AgrícolasFil: Sánchez, Jesús Ricardo. Universidad Autónoma del Estado de México. Facultad de Ciencias AgrícolasFil: León, Carlos de. Universidad Autónoma del Estado de México. Facultad de Ciencias Agrícola

Cytosolic phospholipase A2: a member of the signalling pathway of a new G protein α subunit in Sporothrix schenckii

<p>Abstract</p> <p>Background</p> <p><it>Sporothrix schenckii </it>is a pathogenic dimorphic fungus, the etiological agent of sporotrichosis, a lymphocutaneous disease that can remain localized or can disseminate, involving joints, lungs, and the central nervous system. Pathogenic fungi use signal transduction pathways to rapidly adapt to changing environmental conditions and <it>S. schenckii </it>is no exception. <it>S. schenckii </it>yeast cells, either proliferate (yeast cell cycle) or engage in a developmental program that includes proliferation accompanied by morphogenesis (yeast to mycelium transition) depending on the environmental conditions. The principal intracellular receptors of environmental signals are the heterotrimeric G proteins, suggesting their involvement in fungal dimorphism and pathogenicity. Identifying these G proteins in fungi and their involvement in protein-protein interactions will help determine their role in signal transduction pathways.</p> <p>Results</p> <p>In this work we describe a new G protein α subunit gene in <it>S. schenckii</it>, <it>ssg-2</it>. The cDNA sequence of <it>ssg-2 </it>revealed a predicted open reading frame of 1,065 nucleotides encoding a 355 amino acids protein with a molecular weight of 40.9 kDa. When used as bait in a yeast two-hybrid assay, a cytoplasmic phospholipase A₂catalytic subunit was identified as interacting with SSG-2. The <it>sspla</it>_{<it>2 </it>}gene, revealed an open reading frame of 2538 bp and encoded an 846 amino acid protein with a calculated molecular weight of 92.62 kDa. The principal features that characterize cPLA₂were identified in this enzyme such as a phospholipase catalytic domain and the characteristic invariable arginine and serine residues. A role for SSPLA₂in the control of dimorphism in <it>S. schenckii </it>is suggested by observing the effects of inhibitors of the enzyme on the yeast cell cycle and the yeast to mycelium transition in this fungus. Phospholipase A₂inhibitors such as AACOCF3 (an analogue of archidonic acid) and isotetrandrine (an inhibitor of G protein PLA₂interactions) were found to inhibit budding by yeasts induced to re-enter the yeast cell cycle and to stimulate the yeast to mycelium transition showing that this enzyme is necessary for the yeast cell cycle.</p> <p>Conclusion</p> <p>A new G protein α subunit gene was characterized in <it>S. schenckii </it>and protein-protein interactions studies revealed this G protein alpha subunit interacts with a cPLA₂homologue. The PLA₂homologue reported here is the first phospholipase identified in <it>S. schenckii </it>and the first time a PLA₂homologue is identified as interacting with a G protein α subunit in a pathogenic dimorphic fungus, establishing a relationship between these G proteins and the pathogenic potential of fungi. This cPLA₂homologue is known to play a role in signal transduction and fungal pathogenesis. Using cPLA₂inhibitors, this enzyme was found to affect dimorphism in <it>S. schenckii </it>and was found to be necessary for the development of the yeast or pathogenic form of the fungus.</p