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Spatiotemporal parameters, such as speed, cadence, stride length are often adjusted to enhance stability during walking. Minimal shoes and insoles are known to impact dynamic stability, however their combined effect on such gait parameters in healthy young adults remains unexplored. This cross-sectional study assessed the effects of a minimal shoes, the combination of a minimal shoes with a textured insoles, a minimal shoes with a supportive insoles, barefoot walking and habitual shoes on stability-related spatiotemporal walking gait parameters. Sixty-two healthy young adults (41 males and 21 females, age: 24.6 ± 5.5 years, height: 1.73 ± 0.01 m, weight: 73.8 ± 14.2 kg) were assessed using a 2-minute walk test (2-MWT), and a Timed up and Go (TUG) test in a randomized order of five different footwear conditions. Measurements were made using Kinesis GaitTM and QTUGTM sensors. Repeated measures analyses of covariance were conducted to examine the effect of footwear with gender and BMI as covariates. Results revealed improvement in observed gait parameters during the 2-MWT in minimal shoes, minimal shoes with a textured insoles and minimal shoes with a supportive insoles compared to barefoot and habitual footwear. Participants covered a significantly greater distance (p < 0.05) during the 2-MWT at a self-selected speed in all three minimal shoes conditions with larger stride length and improved cadence. Significant variations (p < 0.05) were found between barefoot walking and minimal shoes conditions while participants being least stable during the barefoot walking. The use of textured or supportive insoles within the minimal shoes did not provide any additional benefits nor did it have any detrimental effect on the spatiotemporal parameters. Nevertheless, minimal shoes with or without insoles have the potential to enhance stability during walking as speed, cadence, and stride length are improved. [ABSTRACT FROM AUTHOR] more...

Non-dispersive infra-red (NDIR) detectors have become the dominant method for measuring atmospheric CO2, which is thought to be an important gas for honeybee colony health. In this work we describe a microcontroller-based system used to collect data from Senserion SCD41 NDIR sensors placed in the crown boards and queen excluders of honeybee colonies. The same sensors also provide relative humidity and temperature data. Several months of data have been recorded from four different hives. The mass change measurements, from hive scales, when foragers leave the hive were compared with the data from the gas sensors. Our data suggest that it is possible to estimate the colony size from the change in measured CO2, however no such link with the humidity is observed. Data are presented showing the CO2 decreasing over many weeks as a colony dies. [ABSTRACT FROM AUTHOR] more...

Honeybee colonies depend on suitable temperatures for successful development. We demonstrate the use of a spatially resolved temperature measurement system for a honeybee colony by producing ten custom frames which results into four hundred eighty sensors across the hive. A first prototype used four layers of wax to embed the sensors, however, the honeybees rejected these and removed the wax before building new, irregular honeycomb. A second system using a single sheet of wax onto which the sensors were laid was accepted by the colony, and normal honeycomb was built. We showcase some of the data collected from this system. [ABSTRACT FROM AUTHOR] more...

The ectoparasitic mite Varroa destructor is considered one of the greatest threats to the honeybee Apis mellifera. To successfully manage mite populations residing in the colony, beekeepers must stay informed of infestation levels in their apiaries. The remote, non-destructive detection of Varroa mites in honeybee hives would therefore be highly desirable. Here we show that an ultra-sensitive (1000 mV/g) accelerometer can detect vibrational waveforms originating from one individual mite. We further focus on a commonly observed pulsing behaviour never before described, characterising its physical features, periodicity and strength. The spectral features of the detected pulses strongly depend on the substrate on which they are produced. The characteristics of the vibrational pulse, particularly its repeatability and strength, indicate that mite vibrations could be successfully detected in a fully populated honeybee hive. These features, combined with the remarkably high varroa muscular power output (up to 810nW) indicate that this pulse may be functional for the mite. Our results uncover an exciting novel behaviour and provide a foundation for the remote detection of mites in beehives using vibration capture. [ABSTRACT FROM AUTHOR] more...

Purpose: This work demonstrates specifically tailored microbubble‐based preparations and their suitability as MRI contrast agents for ingestion and measuring temporal and spatial pressure variation in the human stomach. Methods: Enhanced alginate spheres were prepared by incorporating gas‐filled microbubbles into sodium alginate solution followed by the polymerization of the mixture in an aqueous calcium lactate solution. The microbubbles were prepared with a phospholipid shell and perfluorocarbon gas filling, using a mechanical cavitational agitation regime. The NMR signal changes to externally applied pressure and coming from the enhanced alginate spheres were acquired and compared with that of alginate spheres without microbubbles. In vivo investigations were also carried out on healthy volunteers to measure the pressure variation in the stomach. Results: The MR signal changes in the contrast agent exhibits a linear sensitivity of approximately 40% per bar, as opposed to no measurable signal change seen in the control gas‐free spheres. This novel contrast agent also demonstrates an excellent stability in simulated gastric conditions, including at body temperature. In vivo studies showed that the signal change exhibited in the meal within the antrum region is between 5% and 10%, but appears to come from both pressure changes and partial volume artifacts. Conclusion: This study demonstrates that alginate spheres with microbubbles can be used as an MRI contrast agent to measure pressure changes. The peristaltic movement within the stomach is seen to substantially alter the overall signal intensity of the contrast agent meal. Future work must focus on improving the contrast agent's sensitivity to pressure changes. [ABSTRACT FROM AUTHOR] more...