Oral History Interview: Harold E. Jackson

This interview is one of a series conducted concerning West Virginia business history. Harold E. Jackson was an employee of the Bank of Milton. He discusses: the history of the bank; his educational history; his service in the Navy; his father; his wife; the banking business in general; and the economic recession at the time of the interview.https://mds.marshall.edu/oral_history/1278/thumbnail.jp

Phase-locked loop FM demodulator

A conventional phase-locked loop is improved by replacing its phase detector with one comprising a linear ramp generator and a sample-and-hold circuit, thus eliminating the need for a lowpass loop filter, although the output of the sample-and-hold circuit may be filtered in the case of a very low level modulating signal on the incoming FM signal, but then filtering is not a difficult problem as in a conventional phase-locked loop. The result is FM demodulation by zero-order estimation. For FM demodulation by first-order estimation, the arithmetic difference between adjacent samples is formed, and using a second sample-and-hold circuit an arithmetic difference signal is produced as an input to a second ramp generator that is reset after each sampling cycle to generate a ramp the slope of which is a function of the arithmetic difference signal stored in the second sample-and-hold circuit. The ramp thus generated by the second ramp generator is arithmetically summed with the zero-estimation signal from the first sample-and-hold circuit to form a first-order estimation signal. Filtering such a first-order estimation signal is less of a problem than filtering a zero-order estimation signal

Systematically Controlling for the Influence of Age, Sex, Hertz and Time Post-Whole-Body Vibration Exposure on Four Measures of Physical Performance in Community-Dwelling Older Adults: A Randomized Cross-Over Study

Though popular, there is little agreement on what whole-body vibration (WBV) parameters will optimize performance. This study aimed to clarify the effects of age, sex, hertz and time on four physical function indicators in community-dwelling older adults (N = 32). Participants were exposed to 2 min WBV per session at either 2 Hz or 26 Hz and outcome measures were recorded at 2, 20 and 40 min post-WBV. Timed get up-and-go and chair sit-and-reach performances improved post-WBV for both sexes, were significantly different between 2 Hz and 26 Hz treatments (P ≤ 0.05) and showed statistically significant interactions between age and gender (P ≤ 0.01). Counter movement jump and timed one-legged stance performances showed a similar but non-significant response to 2 Hz and 26 Hz treatments, though male subjects showed a distinct trended response. Age and gender should be statistically controlled and both 2 Hz and 26 Hz exert a treatment effect

The Effectiveness of Using Filmed Courses in Physics and Chemistry in Addition to the Traditional Lecture-Laboratory Courses in High School

The problem of this study was to determine the effectiveness of using filmed courses in physics and chemistry in addition to the traditional lecture-laboratory courses in high school

Effectiveness of Group Kickboxing as a Means to Improve Gait and Balance in Individuals with MS

In recent years, there has been a particular emphasis on identifying and delivering appropriate therapeutic interventions that address the significant balance and gait impairments that affect individuals with multiple sclerosis (MS). Group interventions implemented in community settings have been especially of interest, including tai chi classes. Recently, the authors conducted a preliminary study to examine whether group kick-boxing, which requires more vigorous movements, might be a feasible intervention. Initial findings showed promise and led the authors to pursue a more rigorous follow-up study, with the objective of determining whether a 5-week group kickboxing class improved clinical measures of balance and gait in individuals with MS. Eleven individuals completed the 5-week kickboxing program, which met three times a week for an hour each session. Clinical measures, including the Mini Balance Evaluation Systems Test (BESTest), Berg Balance Scale (BBS), Timed Up and Go (TUG) test, and Dynamic Gait Index (DGI) outcomes, were collected at baseline, before the intervention, and after the intervention. Quiet-standing balance was also measured, and self-reported survey data were collected. Data were analyzed using a Friedman ANOVA-by-ranks test with a Wilcoxon signed rank test as the post hoc comparison. Statistically significant improvements were seen after the intervention in the Mini BESTest, TUG, DGI, and Activities of Balance Confidence. The largest improvements were observed on the Mini BESTest, with a mean of 21.9% improvement between pre- and post-test scores. Participants showed the majority of improvement on tasks that required reactive postural control movements. These movements were similar to skills that were practiced during kickboxing (ie, rapid change of base of support upon kicking). This supports the concept of task-specific transfer, and may indicate why more static-type measures like quiet standing did not indicate similar improvement. Overall, though improvements were not necessarily clinically significant, they did demonstrate the potential and feasibility of the kickboxing concept

Acute Effects of Whole-Body Vibration on Lower Extremity Muscle Performance in Persons With Multiple Sclerosis

Background and Purpose: Whole-body vibration (WBV) is a relatively new form of exercise training that may influence muscle performance. This study investigated the acute effects of high (26 Hz) and low (2 Hz) frequency WBV on isometric muscle torque of the quadriceps and hamstrings in persons with multiple sclerosis (MS). Participants and Method: Fifteen individuals (mean age = 54.6 years, SD = 9.6) with MS and Expanded Disability Status Scale (EDSS) scores ranging from 0-6.5 (mean = 4.2, SD = 2.3) participated in this randomized cross-over study. Following baseline measures of isometric quadricep and hamstring torque, subjects were exposed to 30 seconds of WBV at either 2 or 26 Hz. Torque values were measured again at 1, 10 and 20 minutes post vibration. Subjects returned one week later to repeat the same protocol at the alternate vibration frequency. Results: There were no significant differences in isometric torque production between the 2 and 26Hz WBV conditions. There was also no significant difference between baseline torque values and those measured at 1, 10 and 20 minutes following either vibration exposure. However, there was a consistent trend of higher torque values following the 26 Hz WBV when compared to the 2 Hz condition for both quadriceps and hamstrings. Discussion and Conclusion: Although not statistically significant, peak torque values for both quadriceps and hamstrings were consistently higher following 30 seconds of WBV at 26 vs. 2 Hz. Whether or not WBV presents a viable treatment option as either a warm-up activity or a long-term exercise intervention is yet to be determined. Future studies should include a wider variety of WBV parameters and the use of functional outcome measures