Forearm amputees can use body-powered hooks and myoelectric hands for their daily activities. The body-powered hooks are suitable for delicate manipulation. However, their appearance is not always ...preferred by amputees, and a harness to pull a control cable is not easy to wear. Although the myoelectric hands have a natural appearance similar to the human hand and can be intuitively controlled by a myoelectric control system, they are not easy to try out and are heavy. This paper reports on the Finch, a prosthetic arm with three opposing fingers controlled by a muscle bulge. The aim of developing the Finch is to realize a lightweight prosthetic arm that is easy to wear and use. Three opposing fingers are controlled according to the degree of muscle bulge measured with a muscle bulge sensor on the user's forearm caused by muscle contraction. A supporter socket, consisting of a resin socket frame and a fabric supporter, allows easy fitting. A simple design using a linear actuator and 3D-printed parts achieved light weight (330 g) and low cost. Six functional tests and user tests using Southampton Hand Assessment Procedure showed that the Finch had a practical function that could be used in daily activities.
•Thermal conductivities of JSC-1A and its sieved samples are measured under vacuum.•Thermal conductivity of JSC-1A is similar to that of lunar top surface regolith.•A thermal conductivity model ...calibrated by the experimental results is proposed.
Many air-less planetary bodies, including the Moon, asteroids, and comets, are covered by regolith. The thermal conductivity of the regolith is an essential parameter controlling the surface temperature variation. A thermal conductivity model applicable to natural soils as well as planetary surface regolith is required to analyze infrared remote sensing data. In this study, we investigated the temperature and compressional stress dependence of the thermal conductivity of the lunar regolith simulant JSC-1A, and the temperature dependence of sieved JSC-1A samples under vacuum conditions. We confirmed that a series of the experimental data for JSC-1A are fitted well by our analytical model of the thermal conductivity (Sakatani et al., 2017). Comparison with the calibration data of the sieved samples with those for original JSC-1A indicates that the thermal conductivity of natural samples with a wide grain size distribution can be modeled as mono-sized grains with a volumetric median size. The calibrated model can be used to estimate the volumetric median grain size from infrared remote sensing data. Our experiments and the calibrated model indicates that uncompressed JSC-1A has similar thermal conductivity to lunar top-surface materials, but the lunar subsurface thermal conductivity cannot be explained only by the effects of the density and self-weighted compressional stress. We infer that the nature of the lunar subsurface regolith grains is much different from JSC-1A and lunar top-surface regolith, and/or the lunar subsurface regolith is over-consolidated and the compressional stress higher than the hydrostatic pressure is stored in the lunar regolith layer.
Recent epidemiological studies show that high intakes of carotenoids might be useful to maintain bone health, but little is known about the association of serum carotenoids with change of bone ...mineral density (BMD). The objective of this study was to investigate longitudinally whether serum carotenoids are associated with bone loss.
We conducted a follow-up on 146 male and 99 pre- and 212 post-menopausal female subjects from the Mikkabi study. Those who participated in previous BMD surveys and completed four years of follow-up were examined longitudinally.
During a 4-year follow-up, 15 of the post-menopausal female subjects developed new-onset osteoporosis. In contrast, none of the male and pre-menopausal female subjects did. In male and pre-menopausal female subjects, the six serum carotenoids at the baseline were not associated with bone loss. On the other hand, in post-menopausal female subjects, the 4-year bone loss of radius was inversely associated with the serum carotenoid concentrations, especially in β-carotene. After adjustments for confounders, the odds ratios (OR) for osteoporosis in the highest tertiles of serum β-carotene and β-cryptoxanthin against the lowest tertiles were 0.24 (95% confidence interval 0.05-1.21) and 0.07 (CI: 0.01-0.88), respectively. Serum β-cryptoxanthin was also inversely associated with the risk for osteopenia and/or osteoporosis (P for trend, 0.037). In addition, our retrospective analysis revealed that subjects who developed osteoporosis and/or osteopenia during the survey period had significantly lower serum concentrations of β-cryptoxanthin and β-carotene at the baseline than those in the normal group.
Antioxidant carotenoids, especially β-cryptoxanthin and β-carotene, are inversely associated with the change of radial BMD in post-menopausal female subjects.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Presented here are the observations and interpretations from a comprehensive analysis of 16 representative particles returned from the C-type asteroid Ryugu by the Hayabusa2 mission. On average Ryugu ...particles consist of 50% phyllosilicate matrix, 41% porosity and 9% minor phases, including organic matter. The abundances of 70 elements from the particles are in close agreement with those of CI chondrites. Bulk Ryugu particles show higher δ18O, Δ17O, and ε54Cr values than CI chondrites. As such, Ryugu sampled the most primitive and least-thermally processed protosolar nebula reservoirs. Such a finding is consistent with multi-scale H-C-N isotopic compositions that are compatible with an origin for Ryugu organic matter within both the protosolar nebula and the interstellar medium. The analytical data obtained here, suggests that complex soluble organic matter formed during aqueous alteration on the Ryugu progenitor planetesimal (several 10’s of km), <2.6 Myr after CAI formation. Subsequently, the Ryugu progenitor planetesimal was fragmented and evolved into the current asteroid Ryugu through sublimation.
Assistive suits reduce human muscle effort by improving human motion. However, most assistive suits are bulky, are expensive, need external power sources, and are impractical to carry everywhere. We ...present the development of the pneumatic gel muscle, which can be actuated by very low air pressure, and its characteristics by comparing with a commercially available artificial muscle. We also discuss the design of an unplugged powered suit for walking assist that unloads the muscle effort using the pneumatic gel muscle, demonstrating that assistive forces can be applied without the use of a compressor or air tanks. We performed experiments to measure characteristics of the pneumatic gel muscle, such as the actuation and applied force, for various pressure ranges. We measured surface EMG of the lower limb with and without an unplugged powered suit to identify the unloading effect of the suit.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
TIR, the thermal infrared imager on Hayabusa2, acquired high-resolution thermal images of the asteroid 162173 Ryugu for one asteroid rotation period on August 1, 2018 to investigate the ...thermophysical properties of the asteroid. The surface temperatures of Ryugu suggest that the surface has a low thermal inertia, indicating the presence of porous materials. Thermophysical models that neglect or oversimplify surface roughness cannot reproduce the flat diurnal temperature profiles observed during daytime. We performed numerical simulations of a thermophysical model, including the effects of roughness on the diurnal brightness temperature, the predictions of which successfully reproduced the observed diurnal variation of temperature. The global thermal inertia was obtained with a standard deviation of 225 ± 45 J m−2 s−0.5 K−1, which is relatively low but still within the range of the value estimated in our previous study (Okada et al., Nature 579, 518–522, 2020), confirming that the boulders on Ryugu are more porous in nature than typical carbonaceous chondrites. The global surface roughness (the ratio of the variance of the height relative to a local horizontal surface length) was determined as 0.41 ± 0.08, corresponding to a RMS surface slope of 47 ± 5°. We identified a slightly lower roughness distributed along the equatorial ridge, implying a mass movement of boulders from the equatorial ridge to the mid-latitudes.
•Thermophysical model using a shape model of rough surface reproduces observations.•We obtain a global thermal inertia of 225 ± 45 J m−2 s−0.5 K−1.•We obtain a global RMS surface slope of 47 ± 5°.•We confirm Ryugu's low global thermal inertia owing to porous constituent boulders.
Simultaneous extraction by microwave-irradiation and crystallisation were performed in the same pot of solvent of 70% (v/v) aqueous ethanol for isolation of hesperidin from thinned immature fruit ...peels of
Citrus unshiu as refining of
Citrus waste biomass. The hesperidin content in immature fruits peels was about 3.2-fold higher than that of mature fruit. After microwave-assisted extraction (MAE), the yield of hesperidin reached 58.6
mg/g, which was comparable to the amount obtained after extraction using DMSO:methanol (1:1, v/v) as a solvent for 30
min at room temperature. Heating temperature and time for isolation of hesperidin crystallites were optimised as 140
°C and 8
min by using response surface methodology. Under this optimal condition, 86.8% (47.7
mg/g) of total hesperidin was isolable by MAE and low-temperature storage (5
°C, 24
h).
Martian moons exploration, MMX, is the new sample return mission planned by the Japan Aerospace Exploration Agency (JAXA) targeting the two Martian moons with the scheduled launch in 2024 and return ...to the Earth in 2029. The major scientific objectives of this mission are to determine the origin of Phobos and Deimos, to elucidate the early Solar System evolution in terms of volatile delivery across the snow line to the terrestrial planets having habitable surface environments, and to explore the evolutionary processes of both moons and Mars surface environment. To achieve these objectives, during a stay in circum-Martian space over about 3 years MMX will collect samples from Phobos along with close-up observations of this inner moon and carry out multiple flybys of Deimos to make comparative observations of this outer moon. Simultaneously, successive observations of the Martian atmosphere will also be made by utilizing the advantage of quasi-equatorial spacecraft orbits along the moons’ orbits.
Graphical Abstract
Recent nutritional epidemiological surveys showed that serum β-cryptoxanthin inversely associates with the risks for insulin resistance and liver dysfunction. Consumption of β-cryptoxanthin possibly ...prevents nonalcoholic steatohepatitis (NASH), which is suggested to be caused by insulin resistance and oxidative stress from nonalcoholic fatty liver disease. To evaluate the effect of β-cryptoxanthin on diet-induced NASH, we fed a high-cholesterol and high-fat diet (CL diet) with or without 0.003% β-cryptoxanthin to C56BL/6J mice for 12 weeks. After feeding, β-cryptoxanthin attenuated fat accumulation, increases in Kupffer and activated stellate cells, and fibrosis in CL diet-induced NASH in the mice. Comprehensive gene expression analysis showed that although β-cryptoxanthin histochemically reduced steatosis, it was more effective in inhibiting inflammatory gene expression change in NASH. β-Cryptoxanthin reduced the alteration of expression of genes associated with cell death, inflammatory responses, infiltration and activation of macrophages and other leukocytes, quantity of T cells, and free radical scavenging. However, it showed little effect on the expression of genes related to cholesterol and other lipid metabolism. The expression of markers of M1 and M2 macrophages, T helper cells, and cytotoxic T cells was significantly induced in NASH and reduced by β-cryptoxanthin. β-Cryptoxanthin suppressed the expression of lipopolysaccharide (LPS)-inducible and/or TNFα-inducible genes in NASH. Increased levels of the oxidative stress marker thiobarbituric acid reactive substances (TBARS) were reduced by β-cryptoxanthin in NASH. Thus, β-cryptoxanthin suppresses inflammation and the resulting fibrosis probably by primarily suppressing the increase and activation of macrophages and other immune cells. Reducing oxidative stress is likely to be a major mechanism of inflammation and injury suppression in the livers of mice with NASH.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
An impact experiment was performed on the surface of the C-type asteroid (162173) Ryugu using an instrument called the Small Carry-on Impactor (SCI) carried by the Japan Aerospace Exploration Agency ...spacecraft Hayabusa2. Using a small camera separated from the spacecraft, we observed the development of the ejecta curtain formed by the SCI impact in situ. Based on the patterns appearing in the ejecta curtain, we evaluated the physical properties of large boulders and regolith grains on Ryugu. We found that the large boulders on the surface near the SCI impact point had a compressive strength consistent with the previous estimation of a tensile strength based on low thermal inertia observed for boulders on Ryugu. Furthermore, the ejecta curtain consisted of the boulders with a maximum size of several decimeters. Moreover, the filament structure was formed in the SCI ejecta curtain, strongly suggesting that the SCI impact ejecta curtain particles had a size range greater than one order of magnitude; a characteristic size of the regolith grains in the curtain was estimated to be several centimeters. These regolith grains primarily originated from the subsurface layer. We propose three different hypotheses for the geological process that formed the subsurface structure at the SCI impact point consistent with the above observations. Because these hypotheses have different predictions for materials in SCI ejecta, the samples obtained from the second touchdown will be able to constrain which hypothesis is the most likely.
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