Usability and Acceptance of Exergames Using Different Types of Training among Older Hypertensive Patients in a Simulated Mixed Reality

Virtual and augmented reality (VR/AR) exergames are promising tools for increasing training motivation. However, the use of exergames with mixed reality (MR) headsets remains under-researched. Older adults with hypertension could also benefit from the increased training adherence associated with MR. Endurance and strength endurance exercises are recommended for this group to lower blood pressure. The aim of the preliminary study (n = 22) was to compare the usability and acceptance of two exergames, which represent two different training types-strength endurance training (SET) and endurance training (ET). The developed exergame prototypes were applied in "simulated MR" using a VR head-mounted display. We examined the following outcomes: usability (TUI), intention to use (TUI), subjective task load (NASA-TLX), frustration (NASA-TLX), and presence (PQ). The results showed that frustration was significantly greater in the ET than in the SET (p = 0.038). Presence was significantly higher in the SET (p = 0.002). No significant differences in usability and acceptance were found in the exergames. The results indicate that usability and acceptance are not related to the type of training when utilizing MR exergames. Whether the results are transferable with a real MR headset must be determined in further research

Eavesdropping on Honeybee Communication via Electrostatic Field Recordings

As a canary in a coalmine warns of dwindling breathable air, the honeybee can indicate the health of an ecosystem. Honeybees are the most important pollinators of fruit-bearing flowers, and share similar ecological niches with many other pollinators; therefore, the health of a honeybee colony can reflect the conditions of a whole ecosystem. The health of a colony may be mirrored in social signals that bees exchange during their sophisticated body movements such as the waggle dance. To observe these changes, we developed an automatic system that records and quantifies social signals under normal beekeeping conditions. Here, we describe the system and report representative cases of normal social behavior in honeybees. Our approach utilizes the fact that honeybee bodies are electrically charged by friction during flight and inside the colony, and thus they emanate characteristic electrostatic fields when they move their bodies. These signals, together with physical measurements inside and outside the colony (temperature, humidity, weight of the hive, and activity at the hive entrance) will allow quantification of normal and detrimental conditions of the whole colony. The information provided instructs how to setup the recording device, how to install it in a normal bee colony, and how to interpret its data

Features of adenosine metabolism of mouse heart

Adenosine metabolism and transport were evaluated in the isolated perfused mouse heart and compared with the well-established model of isolated perfused guinea pig heart. Coronary venous release of adenosine under well-oxygenated conditions in the mouse exceeds that in the guinea pig threefold when related to tissue mass. Total myocardial adenosine production rate under this condition was approximately 2 nmol/min per gramme and similar in both species. Coronary resistance vessels of mice are highly sensitive to exogenous adenosine, and the threshold for adenosine-induced vasodilation is approximately 30 nmol/l. Adenosine membrane transport was largely insensitive to nitrobenzyl-thioinosine (NBTI) in mouse heart, which is in contrast to guinea pig and several other species. This indicates the dominance of NBTI-insensitive transporters in mouse heart. For future studies, the assessment of cytosolic and extracellular adenosine metabolism and its relationship with coronary flow will require the use of more effective membrane transport blockers

SAM levels, gene expression of SAM synthetase, methionine synthase and ACC oxidase, and ethylene emission from N. suaveolens flowers

S′adenosyl-l-methionine (SAM) is a ubiquitous methyl donor and a precursor in the biosynthesis of ethylene, polyamines, biotin, and nicotianamine in plants. Only limited information is available regarding its synthesis (SAM cycle) and its concentrations in plant tissues. The SAM concentrations in flowers of Nicotiana suaveolens were determined during day/night cycles and found to fluctuate rhythmically between 10 and 50 nmol g−1 fresh weight. Troughs of SAM levels were measured in the evening and night, which corresponds to the time when the major floral scent compound, methyl benzoate, is synthesized by a SAM dependent methyltransferase (NsBSMT) and when this enzyme possesses its highest activity. The SAM synthetase (NsSAMS1) and methionine synthase (NsMS1) are enzymes, among others, which are involved in the synthesis and regeneration of SAM. Respective genes were isolated from a N. suaveolens petal cDNA library. Transcript accumulation patterns of both SAM regenerating enzymes matched perfectly those of the bifunctional NsBSMT; maximum mRNA accumulations of NsMS1 and NsSAMS1 were attained in the evening. Ethylene, which is synthesized from SAM, reached only low levels of 1–2 ppbv in N. suaveolens flowers. It is emitted in a burst at the end of the life span of the flowers, which correlates with the increased expression of the 1-aminocyclopropane-1-carboxylate oxidase (NsACO)

High Speed Rotary PWM On/Off Valves for Digital Control of Hydraulic Pumps and Motors

University of Minnesota Ph.D. dissertation.August 2014. Major: Mechanical Engineering. Advisors: Perry Li, Thomas Chase. 1 computer file (PDF); x, 182 pages.The research described in this dissertation focuses on the development of innovative on/off valves for high performance, high efficiency control of fixed displacement hydraulic pumps and motors. On/off valves, the hydro-mechanical equivalent of transistors, enable the application of digital control techniques found in electrical systems to hydraulics. These techniques, such as pulse-width-modulation (PWM), have the potential of combining the low cost, high bandwidth characteristics of valve control with the efficiency of variable displacement machines. Effective control of hydraulic systems using PWM requires that the on/off valve simultaneously exhibits fast switching speed, large flow area, and low actuation power. The valves developed in this dissertation exploit continuous rotary motion to achieve the desired, and traditionally competing, operating characteristics. A helical land is used to mechanically embed the desired PWM functionality into the valve spool. The rotary motion of the valve performs the switching functionality while its axial motion determines the PWM duty ratio. Several unique rotary valve concepts are presented in this dissertation for switched-mode pump and pump/motor circuits. An analysis framework is developed that predicts valve performance and typical losses which can be used for design and optimization. Physics based dynamic models of switched-mode pump and motor circuits are also developed for simulating system pressures and flow rates and for validating the analytical models. In addition, guidelines for sizing the valve sleeve based on fatigue considerations are formulated to aid prototype design. Prototype hardware is fabricated and extensively tested to validate the analysis, performance, and predicted efficiency of the proposed valves. The research in this dissertation verifies that helical land rotary valves used in switched-mode hydraulic circuits are capable of exceeding the efficiency of comparable metering valve circuits at moderate PWM frequencies. In two comparable systems, the switched-mode circuit achieved 84% efficiency at 50% output flow compared to 50% efficiency in the bleed off circuit. Analysis also shows that substantial gains in efficiency and switching frequency can be attained with improvements in valve configuration, circuit configuration, and valve geometry. Additional suggestions for further improving efficiency in switched-mode hydraulic systems are also discussed

„Blaming the victim?“ Ergebnisse einer Vignettenstudie zur Stigmatisierung von HIV-positiven Personen

<jats:title>Zusammenfassung</jats:title><jats:sec> <jats:title>Hintergrund</jats:title> <jats:p>Die HIV(„human immundeficiency virus“)-Infizierten sind Diskriminierung in verschiedenen Bereichen ihres Lebens ausgesetzt. Ein Mechanismus der Stigmatisierung in diesem Zusammenhang basiert auf fehlendem Wissen über die Ansteckungswege von HIV.</jats:p> </jats:sec><jats:sec> <jats:title>Ziel der Arbeit</jats:title> <jats:p>Wahrgenommenes Eigenverschulden sowie verantwortungsbewusstes Verhalten bei einer HIV-Infektion werden als mögliche Ursache für die Einschätzung der sozialen Distanz gegenüber HIV-Infizierten untersucht.</jats:p> </jats:sec><jats:sec> <jats:title>Material und Methoden</jats:title> <jats:p>Datengrundlage ist eine Online-Vignettenbefragung, an der insgesamt 135 Personen teilgenommen haben. Die Hypothesen werden mit clusterkorrigierten multiplen linearen Regressionen getestet.</jats:p> </jats:sec><jats:sec> <jats:title>Ergebnisse</jats:title> <jats:p>Wenn eine HIV-Infektion als vermeintlich selbst verschuldet wahrgenommen wird, so ist die soziale Distanz zu den Erkrankten größer. Ähnliche Distanzierung erfahren HIV-infizierte Personen, die beruflich eng mit Menschen zusammenarbeiten, z. B. Beschäftigte des Rettungsdienstes. Vor allem homosexuelle HIV-positive Männer werden stigmatisiert.</jats:p> </jats:sec><jats:sec> <jats:title>Schlussfolgerung</jats:title> <jats:p>Die Stigmatisierung aufgrund von „victim blaming“ gegenüber HIV-Infizierten konnte in dieser Studie aufgezeigt werden.</jats:p> </jats:sec&gt