Differences in teacher qualifications and the relationship to middle school student achievement in mathematics

The purpose of the study was to compare mathematics teacher preparation and experience to the achievement of middle school students (grades 6–8) on the mathematics section of the Texas Assessment of Knowledge and Skills (TAKS). Using a theoretical framework, the research examined the extent to which the teacher qualification variables were related to the student achievement. Measures of teacher qualifications included four independent variables: (a) number of mathematics content hours, (b) level of teaching certification, (c) number of years teaching experience, and (d) number of years teaching middle school/junior high mathematics. Participants in this causal-comparative study included 97 teachers and 6,391 students from the middle schools in Spring Independent and Spring Branch Independent School Districts near Houston, Texas. The researcher obtained the archival test scores from spring 2004 of the respective districts and determined a mean student score for each teacher. The responses to teacher surveys were analyzed using linear regression of the independent variables and showed a 0.04 level of significance between teacher qualifications and student performance on the TAKS. The researcher also examined the ANOVA results which indicated that only the number of years teaching middle school mathematics had a significant relationship to student achievement with a statistical significance (p = .03)

Use of Eelgrass, Zostera marina, Wrack by Three Species of Ladybird Beetles (Coleoptera: Coccinellidae) in Prince Edward Island

Large numbers of the introduced ladybird beetle, Coccinella septempunctata L., were present at Wood Islands and Green Point, Prince Edward Island, in wrack consisting primarily of Zostera marina L. (Eelgrass). The wrack occurred in a 0.5 to 1.0 m band parallel to the shore, and was from five to 25 cm thick. The other ladybirds, Propylea quatuordecimpunctata (L.), an introduced coccinellid also found in high numbers, and an individual of the native Hippodamia tredecimpunctata (Say) were found only at Wood Islands. At both sites the ladybird beetles occurred in the mid-intertidal zone along at least 100 m of shoreline, and were absent to rare on the terrestrial vegetation above the high tide mark. At four of the other eight sites surveyed, occasional individuals were present in the wrack, but they were no more abundant than could be observed on landward vegetation. Mean densities of C. septempunctata at the two primary sites were 52 m-2 (Green Point) and 410 m-2 (Wood Islands)

A Novel Waveform to Extract Exercise Gas Exchange Response Dynamics: The Chirp Waveform

Characterizing exercise gas exchange response dynamics reveals important information about physiological control processes and cardiopulmonary dysfunction. However, current methods for extracting exercise response dynamics typically use multiple step-wise transitions, limiting applicability of this technique. PURPOSE: We designed a new protocol (chirp waveform) to extract exercise gas exchange response dynamics in a single visit. We tested the hypothesis that gas exchange response dynamics extracted from chirp forcing would be similar to those extracted from step-wise transitions. METHODS: Thirty-one participants (14 young healthy, 7 older healthy, and 10 patients with chronic obstructive pulmonary disease) visited the laboratory on three occasions. On visit 1, participants performed a ramp incremental test to determine the gas exchange threshold (GET). On visits 2-3, participants performed either a chirp or step-wise protocol in a randomized order. Chirp forcing consisted of sinusoidal fluctuations in work rate with constant amplitude and progressive shortening of sine periods. Square protocol consisted of 3 square-wave transitions each of 6 min duration. Work rate amplitude (from 20 W to ~95% of the individual’s GET) and exercise duration (30 min) were the same in both protocols. The input-output relationship was characterized using a first-order linear transfer function containing a system gain (K) and time constant (τ) [G(s)= K/(τ×s+1)]. Parameter identification was performed in Matlab using the Matlab System Identification toolbox. Agreement between measures was established using Bland-Altman analysis and Rothery’s Concordance Coefficient (RCC). RESULTS: No systematic bias (mean difference of chirp minus square-wave; Δmean) and good reliability was found for V̇O2 K [Δmean: 0.25(1.03) mL/min/W, p=0.179; RCC: 0.773, p=0.004], V̇O2 τ [Δmean: 0.30(7.08) s, p=0.815; RCC: 0.837, p2 K [Δmean: -0.19(1.57) mL/min/W, p=0.512; RCC: 0.827, pp=0.009] and good reliability (RCC: 0.794, p2 τ. CONCLUSION: The chirp waveform allows extraction of gas exchange response dynamics similar to those obtained from standard methods, thus overcoming the need for multiple tests

Distinguishing Increased Adiposity and/or Aerobic Deconditioning as Moderators of Low VO2peak in Obese Men

Peak oxygen uptake (V̇O2peak) in a cardiopulmonary exercise test (CPET) is a strong predictor of morbidity, mortality, and quality of life. V̇O2peak in obese individuals is typically below the lower limit of normal (2 transport and utilization, i.e. aerobic deconditioning; or both. We hypothesized a modified CPET, to measure the fraction of maximum isokinetic power that can be supported by aerobic metabolism, will distinguish between adiposity and deconditioning effects on V̇O2peak. PURPOSE: To compare V̇O2peak and isokinetic neuromuscular performance in obese vs non-obese men. METHODS: A modified CPET with maximal (3 s) isokinetic cycling power at baseline and the limit of ramp-incremental (RI) exercise was used to calculate: A) baseline maximum isokinetic power (Piso); B) tolerance index (TI), % of Piso at V̇O2peak; C) fatigue index (FI), % reduction in Piso per RI-watt at V̇O2peak; D) power reserve (PR), isokinetic power available at V̇O2peak expressed as % RI-wattpeak. The FRIEND nomogram was used to predict V̇O2peak. Data are mean(SD) and were assessed by t-test. RESULTS: Compared to controls (n=24), obese men (n=20) were older (32(5) vs 26(7) yr), had greater BMI (38(6) vs 23(2) kg/m2), but were not different in stature (177(5) vs 180(7) cm) or predicted V̇O2peak (3.49(0.49) vs 3.58(0.36) L/min). Obese men had lower V̇O2peak (2.84(0.42) vs 3.71(0.45) L/min, p2peak (82(15) vs 104(12) %, pIndependent of body mass, obese men had preserved leg strength (normal Piso), but the fraction of maximum isokinetic power supported by aerobic metabolism at RI intolerance was reduced (low TI) with greater fatigability (high FI); each consistent with aerobic deconditioning. A modified CPET with maximal isokinetic power measurements can distinguish the effects of increased adiposity from aerobic deconditioning on V̇O2peak in obese men