This paper reports on the electromagnetic analysis and experimental testing of a newly invented six-degree of freedom electrodynamic wheel (EDW) magnetic levitation (maglev) vehicle that can stably levitate over a passive low-cost U-guideway. The U-guideway is composed of two sections of L-track aluminum sheet. Both a radial and an axial proof-of-principle EDW maglev vehicle has been built and experimentally tested. The EDW-maglev vehicle contains four one pole-pair diametric magnetized magnets that are driven using a low-cost motor and motor controller. No advanced controls are needed to provide basic stability. A 3-D transient finite element analysis model was used to study the 3-D forces created when the magnets are rotated over the aluminum L-track. The track design
study showed that in addition to providing lateral recentering force the L-track can also be used to increases thrust and lift force.
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COVID-19 lockdowns in early 2020 reduced human mobility, providing an opportunity to disentangle its effects on animals from those of landscape modifications. Using GPS data, we compared movements and road avoidance of 2300 terrestrial mammals (43 species) during the lockdowns to the same period in 2019. Individual responses were variable with no change in average movements or road avoidance behavior, likely due to variable lockdown conditions. However, under strict lockdowns 10-day 95th percentile displacements increased by 73%, suggesting increased landscape permeability. Animals’ 1-hour 95th percentile displacements declined by 12% and animals were 36% closer to roads in areas of high human footprint, indicating reduced avoidance during lockdowns. Overall, lockdowns rapidly altered some spatial behaviors, highlighting variable but substantial impacts of human mobility on wildlife worldwide.
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Abstract Purpose/aim To analyze potential factors associated with levels of selected oral pathogens, as well as total aerobic bacterial species, among nursing home residents.
Materials and methods Nursing home residents were divided into three groups (G1 included people with teeth but no dentures, G2 included people with teeth and dentures, and G3 included people with no teeth and with dentures). All participants had microbiological samples collected from their oral cavity and dentures. Counts of total aerobic bacterial species,
Porphyromonas gingivalis ,Fusobacterium nucleatum ,Actinomyces viscosus ,Aggregatibacter actinomycetemcomitans , andCandida albicans were compared among groups using the Wilcoxon rank sum test. A multivariate analysis was also performed to control other available covariates.Results Bivariate analysis revealed significant differences among the groups, and multivariate analysis showed that sex, the presence of natural teeth, denture wearing, oral hygiene indices, and systemic health conditions were associated with bacterial and
Candida albicans log counts.Conclusions Presence of natural teeth and denture wearing, as well as oral hygiene, sex and systemic health conditions were associated with bacterial and
Candida albicans log counts among nursing home residents.
