147328 research outputs found
Sort by
The wily lion
No full textIt is necessary to have some prior knowledge in EnglishThis is an Aesop's short story which brings some moral. It isn't the entire fable, but just the main idea of itComponente Curricular::Ensino Fundamental::Séries Finais::Língua EstrangeiraComponente Curricular::Ensino Médio::Língua EstrangeiraComponente Curricular::Ensino Médio::LiteraturaComponente Curricular::Educação Superior::Linguística, Letras e Artes::Letra
Secant and tangent lines
No full textCalculus, tangent, secant linesThis Demonstration illustrates the connection between the secant line and the tangent line at a point on a curve. You can vary the point of tangency and the difference h of the x values of the two points defining the secant lineComponente Curricular::Educação Superior::Ciências Exatas e da Terra::Matemátic
Continuous exponential growth
No full textExponential Functions, Calculus and Analytic GeometryContinuous exponential growth, where r is the growth rate, N(t) is the population size, and N(0) is the initial population sizeComponente Curricular::Educação Superior::Ciências Exatas e da Terra::Matemátic
Produção de calor por combustão
No full textNoções básicas sobre energia térmicaGuia esquemático de experimento que possibilita ao aluno observar que é necessário haver combustível e comburente para que a combustão ocorraComponente Curricular::Ensino Médio::Físic
Flammen färbung As
No full textA imagem ilustra o resultado do teste de chama com o elemento arsênio, mostrando sua cor característica quando aquecidoComponente Curricular::Ensino Médio::Químic
Simple harmonic motion of a spring
No full textSimple harmonic motion is a basic type of vibratory motion. This Demonstration plots the time-varying position of a block attached to the end of a spring, showing that the position is described by a sinusoidal waveComponente Curricular::Ensino Médio::FísicaComponente Curricular::Educação Superior::Ciências Exatas e da Terra::Físic
Back in mitosis
No full textPresents video that shows a Xenopus laevis S3 cell reversing cytokinesis and exit from mitosis. The cell is stably expressing GFP alpha-tubulin to visualize dynamics of the microtubule network. This cell was blocked in metaphase with high levels of cyclin B and Cdk1 activity by the addition of the proteasome inhibitor, MG132. Upon treatment with the reversible Cdk inhibitor, Flavopiridol, the cell undergoes cytokinesis without chromosome separation and exits mitosis. Mitotic exit is accompanied by anaphase-like changes in the microtubule network, chromosome decondensation, assembly of the nuclear envelope and formation of a midbody. When the Cdk inhibitor is removed, the midbody recedes and the cleavage furrow re-opens. The mitotic spindle re-forms. The nuclear envelope disassembles. The chromosomes condense and re-align at the metaphase plateComponente Curricular::Educação Superior::Ciências Biológicas::Biologia Gera
HIT A- and B-axes [Secretory pathway; 6b]
No full textPresents two movies, HIT A-Axis on the left and HIT B-Axis on the right constitute the Tilt Series datasets from which the tomogram is calculated. Following acquision of the first (A-Axis) set, the specimen is rotated 90 degrees in the electron microscope and a second set (B-Axis) is acquired about the orthogonal axis. Images were collected at 1.5 degree intervals over a range of 120 degrees in the two axes. These two tilt series provide the primary structural information that is used to reconstruct (movie 6c) and model (movie 6d) the Golgi and nearby structures within the cellComponente Curricular::Educação Superior::Ciências Biológicas::Biologia Gera
Refraction from a submerged light source
No full textA light beam is produced by a source submerged in an aqueous solution of refractive index . This Demonstration shows how the light source appears for different beam directions, divergences, and indices of refraction. The same effect causes a stick obliquely submerged in water to appear bentComponente Curricular::Ensino Médio::Físic
Graphical Linear Programming for Two Variables
No full textThis Demonstration illustrates the graphical solution to several linear programming problems, all of which have the same set of constraints; you can vary the objective function. When two corner points are optimal, so are all the points on the line segment connecting them. The region shaded in blue is the feasible region and the colored lines correspond to the constraints. The black line represents the chosen objective function set to the slider valueComponente Curricular::Educação Superior::Ciências Exatas e da Terra::Matemátic