Predicting student performance in the classroom is an important area of educational research owing to its potential for helping educators identify students who may have difficulty grasping the material in a course. The goal of this research was to develop a sensitive and specific pre-semester assessment for students enrolled in general chemistry for science majors that would identify students at risk for failing the course. The student pre-semester assessment (SPSA) predicted 40.8% of the students who went on to fail first-semester general chemistry. It was a better predictor of at-risk students than the Toledo exam (27.7%), SAT (16.8%), or predicted grade point index (PGI) (29.4%). The inclusion of demographic variables did little to increase the SPSA's predictive power, but math and chemistry background and age significantly increased the accuracy of predicting at-risk students when combined with either the SAT score or the PGI.

The electroencephalogram (EEG) is a physiologic measure of cerebral function that has been used by some to assess coma and prognosticate survival and global outcome after traumatic brain injury (TBI). Surface recordings of the brain's electrical activity reveal distinct patterns that indicate injury severity, depth of unconsciousness, and patient survival. The data produced with traditional qualitative studies, however, does not allow resolution and quantification of the wave frequency spectrum present in the brain. As a result, conventional EEG typically has only been used for gross and qualitative analyses and is not practical for use in long-term patient monitoring or as a sophisticated prognostic tool. One area of investigation that is working to address the limitations of conventional EEG has been the development and implementation of Fourier Transform (FT) EEG which resolves and quantifies frequency bands present in the brain. When FT analysis is applied to EEG, it provides concurrent and continuous monitoring, resolution, and quantification of all frequencies emitted. This review discusses the history and significance of conventional EEG and provides a review of how FT-EEG, commonly referred to as Quantitative EEG (QEEG), is being used in the clinical setting. The specific applications and significance of QEEG methods regarding treatment of patients with TBI are discussed in detail. The advantages, disadvantages, and future directions of QEEG in TBI are also discussed.

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Laser-excited atomic fluorescence has been used to detect lead that was electrothermally atomized from whole blood in a graphite furnace. A 9 kHz repetition rate copper vapor laser pumped dye laser was used to excite the lead at 283.3 nm, and the resulting atomic fluorescence was detected at 405.8 nm. No matrix modification was used other than a 1:21 dilution of the whole blood with high-purity water. Using the atomic fluorescence peak area as the analytical measure and a background correction technique based upon a simultaneous measurement of the transmitted laser intensity, excellent agreement for NIST and CDC certified whole blood reference samples was obtained with aqueous standards. A limit of detection in blood of 10 fg/mL (100 ag absolute) was achieved.

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Reaction stoichiometry calculations have always been difficult for students. This is due to the many different facets the student must master, such as the mole concept, balancing chemical equations, algebraic procedures, and interpretation of a word problem into mathematical equations. Dimensional analysis is one of the main ways students are taught to solve these problems. However, this methodology does not provide all students with a complete understanding of how to solve these problems. Introduction of alternative problem solving techniques, such as proportional reasoning, can help to improve student understanding. The mole ratio flow chart (MRFC) is a logistical sequence of steps that incorporates molar proportions. Students are able to begin analysis of a problem from many different starting points using this MRFC method. Analyses of data collected indicate that MRFC users performed as well on exam problems covering reaction stoichiometry calculations as students using dimensional analysis. Further, class sections exposed to both dimensional analysis and MRFC methods scored as well on exam problems as class sections exposed only to dimensional analysis. These results indicate that the MRFC is a viable alternative method for teaching reaction stoichiometry calculations and for helping to create a more complete understanding of the subject.

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