Standing Weight Perception across Unweighted Conditions in a Lower Body Positive Pressure Treadmill

Lower body positive pressure treadmills (LBPP-TM) provide assistive body weight support to the user by forcing air into an inflatable chamber in which the user is secured. The result of this positive pressure can be experienced as a lift to the user. The degree of chamber air pressure (CAP) determines the amount of supportive lift provided with greater and lesser CAP producing more and less lift, respectively. Exercise studies consistently report lower effort perceptions with greater CAP which suggest a reduced physiological and mechanical strain on the body. What is less well known is the effect on resting perceptions of standing weight (SWP). The purpose of this investigation was to examine the perception of resting standing weight across four different weighted conditions in a LBPP-TM. Nine participants (6 female; overall age: 21.3±1.9 years) stood in a LBPP-TM under the following order of body weight set (BWset) conditions: 100%BWset, 70%BWset, 35%BWset, 90%BWset. A portable Davis Vantage weather station barometer measured CAP inside the inflatable chamber and a 10-cm visual analogue scale measured SWP. Repeated measures analysis of variance evidenced significant changes across CAP (100%BWset: 767.5±4.9 mmHg; 70%BWset: 780.0±3.0 mmHg; 35%BWset: 793.5±3.0 mmHg; 90%BWset: 776.4±7.0 mmHg; all ps ≤ 0.001) except for the 70%BWset and 90%BWset conditions (p = 0.486) and within SWP (90%BWset: 8.8±1.4 cm vs. 70%BWset: 5.8±2.9 cm, p = 0.011; and 35%BWset: 4.6±3.2 cm, p = 0.007) experimental conditions. LBPP-TMs appear to provide robust manipulations of perception across different experimental contexts. Similar to findings from exercise studies, greater CAP and its resultant lift produced significant reduced perceptions of standing weight while at rest.https://digitalcommons.cortland.edu/slides/1025/thumbnail.jp

Blood Pressure Responses during Three Unweighted Conditions in a Lower Body Positive Pressure Treadmill

During exercise, lower leg muscle activation has been shown to increase venous return, exercise cardiac output, and arterial blood pressure (BP). Here we investigate BP at rest, with an increase in lower body pressure by unweighting volunteers in a lower body positive pressure treadmill (LBPP-TM). The purpose of this study was twofold; to determine if BP changes while standing over five-minute stages in response to four conditions. Nine participants (21.3±1.8 years) stood in a LBPP-TM in the following ordered conditions: 100%BWset (no unweighting, control), 70%BWset, 35%BWset, and 90%BWset (35%BWset is the greatest unweighted condition). A SunTech® automatic BP cuff measured systolic and diastolic BP (SBP and DBP, respectively). SBP and DBP was measured once during 100%BWset and averaged over the five-minute stages during 70%BWset, 35%BWset, and 90%BWset. A portable Davis Vantage weather station inside the chamber measured chamber air pressure (CAP). Repeated measures analysis of variance evidenced significant differences in only SBP (p = 0.006) at 100%BWset (no unweighting) and 90%BWset (129±11 mmHg and 120±8 mmHg, respectively). DBP did not show any significant differences across conditions (ps \u3e 0.091). CAP at 100%BWset (767.5±4.9 mmHg) was lower compared to 70%BWset (780.0±3.0 mmHg), 35%BWset (793.5±3.0 mmHg), and 90%BWset (776.4±7.0 mmHg) (p\u3c0.001, p\u3c0.001, and p=0.001, respectively). 35%BWset CAP was also higher than 70%BWset and 90%BWset (ps\u3c0.001 for both), but 70%BWset and 90%BWset CAPs were not different (p = 0.486). The initial findings suggest a quick reduction in CAP (35%BWset to 90%BWset) may decrease SBP below starting levels at 100%BWset. Though the sample consists of healthy, young adults and there was only a 9.0 mmHg decrease in SBP, individuals who are intolerant to SBP changes or older adults may need a slower reduction in CAP from highly unweighted conditions to account for SBP changes as they return to baseline CAP.https://digitalcommons.cortland.edu/slides/1022/thumbnail.jp

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Comparison of Resting Heart Rates: Three Devices and Three Alter(ed) Pressures

Accurate heart rate (HR) measurements are key to exercise prescription. Many portable HR devices are available including the Apple watch. Resting HR from Apple series 3 watch were compared to measurements using a clinal grade Suntech Tango M2 (ST) and Vitalstream Caretaker (VS) pulse monitors. College-aged participants (N = 5) stood in the Alter G treadmill under positive pressures of 70%, 35%, and 90% body weight (BWset), respectively. Heart rates using each device were recorded at min 1, 3, and 5 for each condition. There were no significant differences in resting heart rates measured with the three devices. Average heart rates (±SD) at 70% BWset were 83±10, 82±12, 82±12; at 35% BWset were 79±8, 79±10, 81±11; and at 90% BWset were 88±11, 88±12, 89±10 for Apple, ST, and VS, respectively. All three devices measured a significant change in heart rate as a function of change in BWset (p\u3c0.001).https://digitalcommons.cortland.edu/slides/1024/thumbnail.jp

The spatial and temporal distribution of SARS-CoV-2 from the built environment of COVID-19 patient rooms: A multicentre prospective study.

BackgroundSARS-CoV-2 can be detected from the built environment (e.g., floors), but it is unknown how the viral burden surrounding an infected patient changes over space and time. Characterizing these data can help advance our understanding and interpretation of surface swabs from the built environment.MethodsWe conducted a prospective study at two hospitals in Ontario, Canada between January 19, 2022 and February 11, 2022. We performed serial floor sampling for SARS-CoV-2 in rooms of patients newly hospitalized with COVID-19 in the past 48 hours. We sampled the floor twice daily until the occupant moved to another room, was discharged, or 96 hours had elapsed. Floor sampling locations included 1 metre (m) from the hospital bed, 2 m from the hospital bed, and at the room's threshold to the hallway (typically 3 to 5 m from the hospital bed). The samples were analyzed for the presence of SARS-CoV-2 using quantitative reverse transcriptase polymerase chain reaction (RT-qPCR). We calculated the sensitivity of detecting SARS-CoV-2 in a patient with COVID-19, and we evaluated how the percentage of positive swabs and the cycle threshold of the swabs changed over time. We also compared the cycle threshold between the two hospitals.ResultsOver the 6-week study period we collected 164 floor swabs from the rooms of 13 patients. The overall percentage of swabs positive for SARS-CoV-2 was 93% and the median cycle threshold was 33.4 (interquartile range [IQR]: 30.8, 37.2). On day 0 of swabbing the percentage of swabs positive for SARS-CoV-2 was 88% and the median cycle threshold was 33.6 (IQR: 31.8, 38.2) compared to swabs performed on day 2 or later where the percentage of swabs positive for SARS-CoV-2 was 98% and the cycle threshold was 33.2 (IQR: 30.6, 35.6). We found that viral detection did not change with increasing time (since the first sample collection) over the sampling period, Odds Ratio (OR) 1.65 per day (95% CI 0.68, 4.02; p = 0.27). Similarly, viral detection did not change with increasing distance from the patient's bed (1 m, 2 m, or 3 m), OR 0.85 per metre (95% CI 0.38, 1.88; p = 0.69). The cycle threshold was lower (i.e., more virus) in The Ottawa Hospital (median quantification cycle [Cq] 30.8) where floors were cleaned once daily compared to the Toronto hospital (median Cq 37.2) where floors were cleaned twice daily.ConclusionsWe were able to detect SARS-CoV-2 on the floors in rooms of patients with COVID-19. The viral burden did not vary over time or by distance from the patient's bed. These results suggest floor swabbing for the detection of SARS-CoV-2 in a built environment such as a hospital room is both accurate and robust to variation in sampling location and duration of occupancy

Speech Act Theory and the Study of Argumentation

In this paper, the influence of speech act theory and Grice’s theory of conversational implicature on the study of argumentation is discussed. First, the role that pragmatic insights play in van Eemeren and Grootendorst’s pragma-dialectical theory of argumentation and Jackson and Jacobs’ conversational approach to argumentation is described. Next, a number of examples of recent work by argumentation scholars is presented in which insights from speech act theory play a prominent role