Accuracy of Wrist-Worn Monitors while Walking in Lower Limb Prosthetic Users

TACSM Abstract Accuracy of Wrist-Worn Monitors while Walking in Lower Limb Prosthetic Users BRIAN G. BURKHOLDER and JOHN D. SMITH Department of Counseling, Health, & Kinesiology, Texas A&M University-San Antonio, San Antonio, TX Category: Undergraduate Advisor / Mentor: Smith, John ([email protected]) ABSTRACT Wrist-worn activity monitors are extremely popular among the general population. These monitors are used to track activity for purposes to lose weight, get healthy, improve performance, and other reasons. While many studies have looked at the accuracy of these monitors in individuals without amputations, there has yet to be any that have examined these monitors in those who use lower-limb prosthetics. PURPOSE: to determine the accuracy of wrist-worn activity monitors in individuals using lower-limb prosthetics. METHODS: Thirty-four men and women (Age: 48.8±14.2 yrs, Ht: 176.9±11.5 cm, Wt: 88.3±21.1 kg, BMI: 28.3±5.3) with right-, left-leg, or bilateral above and below the knee amputations were fitted with a Polar Loop (PL) and a Fitbit ChargeTM (FC) on the left wrist, and an Omron HJ-112 (OM) pedometer on the left hip. After resetting the monitors, they then walked 140m at a self-selected pace followed by the investigator who counted steps with a standard lab hand-tally counter for actual counts (AC). At the conclusion of the walk, step counts were recorded from all devices. A repeated measures ANOVA was used to determine differences in counts registered by the monitors and those registered by AC. Single measure intraclass correlation (ICC) from a two-way random effects ANOVA was used to assess the agreement between AC and monitor counts, with ≥ 0.90 considered high agreement, 0.80 to 0.89 moderate agreement, and ≤ 0.79 low agreement. Bland-Altman plots of AC vs. counts registered by the monitors were used to provide an indication of over/under representation of steps and agreement between the measures. Percent error was calculated as [(counts detected by monitor – AC) / AC] x 100. Alpha was set at .05 for all statistical tests. RESULTS: There was a significant difference between counts, F(3, 30)=8.8, p=.001, with pairwise comparisons indicating PL was significantly lower than AC, p=.001. There was no significant difference between AC and FC (p\u3e.05) or between AC and OM (p\u3e.05). Agreement according to ICC between AC and PL was low (α=.71, ICC=.42 to .86), between AC and FC was moderate (α =.81, ICC=.61 to .90), and between AC and OM was high (α =.93, ICC=.86 to .97). Bland Altman plots indicate lowest agreement between AC and PL, and with highest agreement between AC and OM. Percent error was greatest with PL (16±12%), lower with FC (8.9±8.9%), and least with OM (4.1±7.3%). CONCLUSION: It seems that for this population who might consider wearing either the PL or the FC, the FC would be a better choice given its greater accuracy. Interestingly, the OM is the superior device for counting steps

The Standardized Fish Bioassay Procedure for Detecting and Culturing Actively Toxic Pfiesteria, Used by Two Reference Laboratories for Atlantic and Gulf Coast States

In the absence of purified standards of toxins from Pfiesteria species, appropriately conducted fish bioassays are the gold standard that must be used to detect toxic strains of Pfiesteria slop. from natural estuarine water or sediment samples and to culture actively toxic Pfiesteria. In this article, we describe the standardized steps of our fish bioassay as an abbreviated term for a procedure that includes two sets of trials with fish, following the Henle-Koch postulates modified for toxic rather than infectious agents. This procedure was developed in 1991, and has been refined over more than 12 years of experience in research with toxic Pfiesteria. The steps involve isolating toxic strains of Pfiesteria (or other potentially, as-yet-undetected, toxic Pfiesteria or Pfiesteria-like species) from fish-killing bioassays with natural samples; growing the clones with axenic algal prey; and retesting the isolates in a second set of fish bioassays. The specific environmental conditions used (e.g., temperature, salinity, light, other factors) must remain flexible, given the wide range of conditions from which natural estuarine samples are derived. We present a comparison of information provided for fish culture conditions, reported in international science journals in which such research is routinely published, and we provide information from more than 2,000 fish bioassays with toxic Pfiesteria, along with recommendations for suitable ranges and frequency of monitoring of environmental variables. We present data demonstrating that algal assays, unlike these standardized fish bioassays, should not be used to detect toxic strains of Pfiesteria spp. Finally, we recommend how quality control/assurance can be most rapidly advanced among laboratories engaged in studies that require research-quality isolates of toxic Pfiesteria spp

Generalized Huygens principle with pulsed-beam wavelets

Huygens' principle has a well-known problem with back-propagation due to the spherical nature of the secondary wavelets. We solve this by analytically continuing the surface of integration. If the surface is a sphere of radius $R$, this is done by complexifying $R$ to $R+ia$. The resulting complex sphere is shown to be a real bundle of disks with radius $a$ tangent to the sphere. Huygens' "secondary source points" are thus replaced by disks, and his spherical wavelets by well-focused pulsed beams propagating outward. This solves the back-propagation problem. The extended Huygens principle is a completeness relation for pulsed beams, giving a representation of a general radiation field as a superposition of such beams. Furthermore, it naturally yields a very efficient way to compute radiation fields because all pulsed beams missing a given observer can be ignored. Increasing $a$ sharpens the focus of the pulsed beams, which in turn raises the compression of the representation.Comment: 49 pages, 14 figure

Kinetics of a Diffusive Capture Process: Lamb Besieged by a Pride of Lions

The survival probability, S_N(t), of a diffusing prey (``lamb'') in the proximity of N diffusing predators (a ``pride of lions'') in one dimension is investigated. When the lions are all to one side of the lamb, the survival probability decays as a non-universal power law, S_N(t) is proportional to t^{-beta_N}, with the decay exponent beta_N proportional to ln N. The crossover behavior as a function of the relative diffusivities of the lions and the lamb is also discussed. When N--->oo, the lamb survival probability exhibits a log-normal decay, exp(-ln^2 t).Comment: 12 pages, no figures, macro files prepended, to be submitted to J. Phys.

Thermodynamics and Universality for Mean Field Quantum Spin Glasses

We study aspects of the thermodynamics of quantum versions of spin glasses. By means of the Lie-Trotter formula for exponential sums of operators, we adapt methods used to analyze classical spin glass models to answer analogous questions about quantum models.Comment: 17 page

Emerging Marine Diseases: Climate Links and Anthropogenic Factors

Mass mortalities due to disease outbreaks have recently affected major taxa in the oceans. For closely monitored groups like corals and marine mammals, reports of the frequency of epidemics and the number of new diseases have increased recently. A dramatic global increase in the severity of coral bleaching in 1997-98 is coincident with high El Niño temperatures. Such climate-mediated, physiological stresses may compromise host resistance and increase frequency of opportunistic diseases. Where documented, new diseases typically have emerged through host or range shifts of known pathogens. Both climate and human activities may have also accelerated global transport of species, bringing together pathogens and previously unexposed host populations

Prevalence and Types of Drugs Used Among Hepatitis A Patients During Outbreaks Associated with Person-to-Person Transmission, Kentucky, Michigan, and West Virginia, 2016–2019

Background: People who use drugs are at increased risk for hepatitis A virus infection. Since 1996, the Advisory Committee on Immunization Practices has recommended hepatitis A vaccination for people who use drugs. Since 2016, the U.S. has experienced widespread hepatitis A outbreaks associated with person-to-person transmission. Purpose: To describe the prevalence of drug use, route of use, and drugs used among hepatitis A outbreak-associated patients. Methods: State outbreak and medical records were reviewed to describe the prevalence, type, and route of drug use among a random sample of 812 adult outbreak-associated hepatitis A patients from Kentucky, Michigan, and West Virginia during 2016–2019. Differences in drug-use status were analyzed by demographic and risk-factor characteristics using the χ2 test. Results: Among all patients, residents of Kentucky (55.6%), Michigan (51.1%), and West Virginia (60.1%) reported any drug use, respectively. Among patients that reported any drug use, methamphetamine was the most frequently reported drug used in Kentucky (42.3%) and West Virginia (42.1%); however, opioids were the most frequently reported drug used in Michigan (46.8%). Hepatitis A patients with documented drug use were more likely (p\u3c0.05) to be experiencing homelessness/unstable housing, have been currently or recently incarcerated, and be aged 18–39 years compared to those patients without documented drug use. Implications: Drug use was prevalent among person-to-person hepatitis A outbreak-associated patients, and more likely among younger patients and patients experiencing homelessness or incarceration. Increased hepatitis A vaccination coverage is critical to prevent similar outbreaks in the future

Fine material in grain

Fine material in grain: an overview / Richard Stroshine -- Factors that affect the costs of fines in the corn export market / Lowell D. Hill, Mack Leath -- Effects of fine material on mold growth in grain / David B. Sauer, Richard A. Meronuck, John Tuite -- Effects of fine material on insect infestation: a review / Paul W. Flinn, William H. McGaughey, Wendell E. Burkholder -- Reducing or controlling damage to grain from handling: a review / Charles R. Martin, George H. Foster -- Evaluating grain for potential production of fine material - breakage susceptibility testing / Steven R. Eckhoff -- Genotypic differences in breakage susceptibility of corn and soybeans -- M. R. Paulsen, L. L. Darrah, R. L. Stroshin