Relationships Between Diet, Exercise and Learning in the Regular Science Classroom Setting

The purpose of this study is to examine how diet and exercise relate to student achievement and learning in the regular classroom setting. Research questions include whether or not there is a positive correlation between the amount/type of exercise a student receives per week and learning, as well as relationships between their diet and learning in the classroom. Forty high school honors biology students were surveyed as to their dietary and exercise habits. This data was compared to their individual average test grades as a measure of learnin

Relationships Between Diet, Exercise and Learning in the Regular Science Classroom Setting

The purpose of this study is to examine how diet and exercise relate to student achievement and learning in the regular classroom setting. Research questions include whether or not there is a positive correlation between the amount/type of exercise a student receives per week and learning, as well as relationships between their diet and learning in the classroom. Forty high school honors biology students were surveyed as to their dietary and exercise habits. This data was compared to their individual average test grades as a measure of learnin

Color Image-Analyzed Fluorescence Microscopy: A New Tool For Marine Microbial Ecology

BACTERIA, cyanobacteria, protozoa and small eukaryotic phytoplankton are now known to be funda- mental components of marine planktonic ecosystems (Azam et al., 1983; Sieburth, 1984). These organisms have high potential growth rates, are efficient convert- ers of material and energy, and usually constitute most of the plankton biomass (Davis et al., 1985; Fuhrman et al., 1989). Their different trophic levels are often closely coupled. These characteristics require that experimental and sampling designs for studying the microbial populations incorporate appropriate (i.e., small) temporal and spatial scales. The corollary to this is that large numbers of samples must be taken. If these can be processed rapidly, sampling designs can be modified to existing conditions. Quantifying the abun- dance and biovolume of these microbial cells is difficult because these organisms are extremely small and cell biovolume is a cubic function of linear dimensions. These difficulties are major obstacles to developing realistic trophodynamic models

Measurement Of Marine Picoplankton Cell-Size By Using A Cooled, Charge-Coupled Device Camera With Image-Analyzed Fluorescence Microscopy

Accurate measurement of the biomass and size distribution of picoplankton cells (0.2 to 2.0-mu-m) is paramount in characterizing their contribution to the oceanic food web and global biogeochemical cycling. Image-analyzed fluorescence microscopy, usually based on video camera technology, allows detailed measurements of individual cells to be taken. The application of an imaging system employing a cooled, slow-scan charge-coupled device (CCD) camera to automated counting and sizing of individual picoplankton cells from natural marine samples is described. A slow-scan CCD-based camera was compared to a video camera and was superior for detecting and sizing very small, dim particles such as fluorochrome-stained bacteria. Several edge detection methods for accurately measuring picoplankton cells were evaluated. Standard fluorescent microspheres and a Sargasso Sea surface water picoplankton population were used in the evaluation. Global thresholding was inappropriate for these samples. Methods used previously in image analysis of nanoplankton cells (2 to 20-mu-m) also did not work well with the smaller picoplankton cells. A method combining an edge detector and an adaptive edge strength operator worked best for rapidly generating accurate cell sizes. A complete sample analysis of more than 1,000 cells averages about 50 min and yields size, shape, and fluorescence data for each cell. With this system, the entire size range of picoplankton can be counted and measured

Biological And Hydrodynamic Regulation Of The Microbial Food-Web In A Periodically Mixed Estuary

Abundances of chroococcoid cyanobacteria and heterotrophic bacteria in surface waters of the York River subestuary covary with spring-neap tidally induced changes in the mixed-layer depth. Abundances of their principal grazers, heterotrophic protists, however, do not oscillate. A simulation model of this system using nonlinear, density-dependent functions has been developed to replicate cycles observed in the two bacterial abundances and simulate bacterial production and protistan grazing. A Jassby-Plan equation is used to determine growth rate from the mean mixed-layer light and empirically derived growth and a parameters. Changes in mixed-layer depth regulate light availability, thereby controlling cyanobacterial growth rates. The model predicts a close coupling between cyanobacterial growth and during destratified periods when cyanobacterial stocks are low. During stratified periods when cyanobacteria biomass values are high, the model suggests that grazing is saturated and has little effect on cyanobacterial biomass. Grazing on heterotrophic bacteria is rarely saturated and is only loosely coupled to heterotrophic bacteria production during destratification. The model was tested at several grazer feeding preferences for cyanobacteria or heterotrophic bacteria and reproduced observed microbial biomass values most accurately when there was no initial preference. These model dynamics suggest that the heterotrophic protists fed equally well on both heterotrophic bacteria and cyanobacteria

Algorithm To Estimate Cell Biovolume Using Image Analyzed Microscopy

This paper describes an algorithm for calculating the biovolume of cells with simple shapes, such as bacteria, flagellates, and simple ciliates, from a 2-dimensional digital image. The method can be adapted to any image analysis system which allows access to the binary cell image-( i.e., the pixels, or (x,y) points, composing the cell. The cell image is rotated to a standard orientation (horizontal), inand a solid of revolution is calculated by digital integration. Verification and a critical assessment of the method are presented. The algorithm accounts for irregularities in cell shape that conventional methods based on length, width, and geometrical formulas do not

Data acquisition from digital holograms of particles

A technique for data acquisition from digital holograms of particle ensembles, including preprocessing of the digital hologram, construction of a two-dimensional display of the holographic image of investigated volume, and segmentation and measurement of particle characteristics is considered. The proposed technique is realized in automatic regime and can work in real time. Results of the technique approbation using digital holograms of sand, plankton particles in water, and air bubbles in oil are presented