12,759 research outputs found
An Investigative Approach to Teaching Mathematics: Excitement and Concerns of K-8 Preservice Teachers
Following from the recommendations of the National Council of Teachers of Mathematics, an Investigative Approach (IA) to teaching mathematics encourages students to explore real-world problems through hands-on activities instead of focusing on rote memorization of facts, formulas, and procedures. This paper discusses thirty-two K-8 preservice teachers‘ responses to questions regarding excitements and concerns about using this method of teaching. Although most preservice teachers are excited about the prospects of using this approach in their future classrooms, some exhibit hesitations related to concerns about time constraints and their own math abilities. A mathematics methods course presently being taught that is centered around the ideas of IA is discussed, and recommendations for the use of IA in preservice math methods courses to help teachers overcome these concerns are made
A new homeostat
Homeostasis concepts, and design of simple adaptive controlle
Sonic boom effect on fish: Observations
Motion pictures of fish in a small tank at the time a bullet traveling 1200 m/sec passes a few centimeters above indicate that fish sense the passage of the shock wave but suffer no ill effects. The pressure rise at the bow shock wave was 0.26 atm or 275 times that associated with a strong sonic boom, for example, from the proposed supersonic transport
Automated single-slide staining device
A simple apparatus and method is disclosed for making individual single Gram stains on bacteria inoculated slides to assist in classifying bacteria in the laboratory as Gram-positive or Gram-negative. The apparatus involves positioning a single inoculated slide in a stationary position and thereafter automatically and sequentially flooding the slide with increments of a primary stain, a mordant, a decolorizer, a counterstain and a wash solution in a sequential manner without the individual lab technician touching the slide and with minimum danger of contamination thereof from other slides
Microbiological surface sampling cart
Mobile sampling cart automatically swabs surfaces for the recovery of microorganisms. Unit operates without human involvement and provides for control of swabbing speed, rotation of cotton swab, and the pressure and angle applied to swab. Capability of reverse direction is also available. Sampling cart use is limited to flat surfaces
Automatic microbial transfer
Device can transfer metabolites or inhibitory agents to broth cultures of bacteria, in various stages of growth, for study. It also has application in transfer of other micro-organisms, such as yeasts, and could be useful in clinical and research laboratories. Device has been used for wide variety of purposes in experimental situations
Apparatus for microbiological sampling
An automatic apparatus is described for microbiologically sampling surface using a cotton swab which eliminates human error. The apparatus includes a self-powered transport device, such as a motor-driven wheeled cart, which mounts a swabbing motor drive for a crank arm which supports a swab in the free end thereof. The swabbing motor is pivotably mounted and an actuator rod movable responsive to the cart traveling a predetermined distance provides lifting of the swab from the surface being sampled and reversal of the direction of travel of the cart
Providing Real-World Experiences: the Virginia Tech Externship for Mathematics Specialists
We describe the structure and implementation of the yearlong Externship experience associated with the Mathematics Specialist program at Virginia Polytechnic Institute & State University (Virginia Tech). We discuss the assignments and experiences included in the Externship, the alignment of those experiences with the job description developed by the Virginia Mathematics and Science Coalition Task Force, and teacher comments on the effectiveness of their Externship experiences [1]
Automated single-slide staining system
Apparatus developed to Gram-stain single slides automatically is flexible enough to accommodate other types of staining procedures. Method frees operator and eliminates necessity for subjective evaluations as to length of staining or decolorizing time
- …