Background
A gut–muscle axis through which the microbiome influences skeletal muscle has been hypothesized. However, sex‐specific association between the characteristics of gut microbiota and ...skeletal muscle mass has not yet been reported. Herein, we performed sex‐specific analyses of faecal microbiota composition for the skeletal muscle mass in a population‐based cohort.
Methods
We collected faecal samples of 1052 middle‐aged participants (621 men and 431 women) who attended health screenings, and we analysed the intestinal microbiota using 16S rRNA gene sequencing. Relative muscle mass was calculated using a bioelectrical impedance analysis and presented as the skeletal muscle mass index SMI (%) = total appendicular muscle mass (kg)/weight (kg) × 100. We categorized the subjects into four groups by the quartile of the SMI. Association tests between gut microbiota and SMI were conducted according to the microbial diversity, taxonomic profiling and functional inference in a sex‐stratified manner.
Results
The mean age and SMI of the total participants were 44.8 years (standard deviation SD, 8.2) and 41.4% (SD, 3.9), respectively. After adjustments for possible covariates such as age, body mass index and regular physical activity, the highest quartile (Q4) group of SMI had higher alpha diversity than the lowest quartile (Q1) group in male participants (coefficient = 10.79, P < 0.05, linear regression model), whereas there was no difference in diversity among SMI groups in females. At the species level, Haemophilus parainfluenzae (coefficient = 1.910) and Roseburia faecis (coefficient = 1.536) were more abundant in the highest SMI (Q4) group than in the lowest SMI (Q1) group in males. However, no significant taxon was observed along the SMI groups in females. The gut microbiota of the lowest SMI group (Q1) was enriched with genes involved in biosynthesis of amino acids and energy generation compared with that of the highest SMI group (Q4) in both sexes, although the significance of the inferred pathways was weak (P < 0.05 but the false discovery rate q > 0.05).
Conclusions
In this large sample of middle‐aged individuals, this study highlights fundamental sex‐specific differences in the microbial diversity, composition and metabolic pathways inferred from gut microbiota according to SMI. The gut microbiota may provide novel insights into the potential mechanisms underlying the sex dependence of skeletal muscle mass.
Low modulus, compliant systems of sensors, circuits and radios designed to intimately interface with the soft tissues of the human body are of growing interest, due to their emerging applications in ...continuous, clinical-quality health monitors and advanced, bioelectronic therapeutics. Although recent research establishes various materials and mechanics concepts for such technologies, all existing approaches involve simple, two-dimensional (2D) layouts in the constituent micro-components and interconnects. Here we introduce concepts in three-dimensional (3D) architectures that bypass important engineering constraints and performance limitations set by traditional, 2D designs. Specifically, open-mesh, 3D interconnect networks of helical microcoils formed by deterministic compressive buckling establish the basis for systems that can offer exceptional low modulus, elastic mechanics, in compact geometries, with active components and sophisticated levels of functionality. Coupled mechanical and electrical design approaches enable layout optimization, assembly processes and encapsulation schemes to yield 3D configurations that satisfy requirements in demanding, complex systems, such as wireless, skin-compatible electronic sensors.
There have been few large-scale studies on the relationship between smoking and gut microbiota. We investigated the relationship between smoking status and the composition of gut microbiota. This was ...a population-based cross-sectional study using Healthcare Screening Center cohort data. A total of 758 men were selected and divided into three groups: never (
= 288), former (
= 267), and current smokers (
= 203). Among the three groups, there was no difference in alpha diversity, however, Jaccard-based beta diversity showed significant difference (
= 0.015). Pairwise permutational multivariate analysis of variance (PERMANOVA) tests between never and former smokers did not show a difference; however, there was significant difference between never and current smokers (
= 0.017) and between former and current smokers (
= 0.011). Weighted UniFrac-based beta diversity also showed significant difference among the three groups (
= 0.038), and pairwise PERMANOVA analysis of never and current smokers showed significant difference (
= 0.01). In the analysis of bacterial composition, current smokers had an increased proportion of the phylum Bacteroidetes with decreased Firmicutes and Proteobacteria compared with never smokers, whereas there were no differences between former and never smokers. In conclusion, gut microbiota composition of current smokers was significantly different from that of never smokers. Additionally, there was no difference in gut microbiota composition between never and former smokers.
Electrohydrodynamic (EHD) inkjet printing is an efficient technique for printing multiple sensors in a multifaceted area. It can be applied to various fields according to the shape of the printing ...result and the algorithm employed. In this study, temperature sensors capable of detecting heat sources were fabricated. Inks suitable for EHD inkjet printing were produced, and optimal parameters for printing were determined. Printing was performed using the corresponding parameters, and various printing results were obtained. Furthermore, an experiment was conducted to confirm the temperature measurement characteristics of the results and the tolerance of the sensor. Grid-type sensors were fabricated based on the results, and the sensor characteristics were confirmed in an orthogonal form. Heat was applied to arbitrary positions. Resistance to changes due to heat was measured, and the location at which the heat was generated was detected by varying the change in resistance. Through this study, efficient heat control can be achieved, as the location of the heat source can be identified quickly.
Abstract
Earlier research has been primarily focused on WC as one of the most promising earth-abundant electrocatalysts for hydrogen evolution reaction (HER), whereas the other compound in this ...carbide family—W
2
C—has received far less attention. Our theoretical calculations suggest that such a focus is misplaced and W
2
C is potentially more HER-active than WC. Nevertheless, the preparation of phase pure and sintering-free W
2
C nanostructures represents a formidable challenge. Here we develop an improved carburization method and successfully prepare ultrasmall and phase-pure W
2
C nanoparticles. When evaluated for HER electrocatalysis, W
2
C nanoparticles exhibit a small onset overpotential of 50 mV, a Tafel slope of 45 mV dec
−1
and outstanding long-term cycling stability, which are dramatically improved over all existing WC-based materials. In addition, the integration of W
2
C nanoparticles with p-type Si nanowires enables highly active and sustainable solar-driven hydrogen production. Our results highlight the great potential of this traditionally non-popular material in HER electrocatalysis.
Measuring the temperature of satellites is crucial for thermal control. Efficient heat control is possible when the location of the heat source can be quickly identified and the heat transfer area ...can be measured. Grid-type thin-film temperature sensors have been proposed for this purpose. Grid-type thin-film temperature sensors use electrohydrodynamic (EHD) inkjet printing technology, a next-generation printing technology. Sensors with high sensing resolution can be manufactured using these technologies. However, the EHD inkjet printing technology is sensitive to printing conditions, and determining the optimal conditions is crucial. Therefore, we produce inks for application in EHD inkjet printing technology and conduct experiments to validate their characteristics. In addition, we determine the optimal conditions for printing and manufacturing grid-type thin-film temperature sensors. The heating element is placed at an arbitrary location and the location of heat generation is detected using the manufactured temperature sensors. We have obtained visualization data showing the heat distribution with time. As a result, the production of a grid-type thin film temperature sensor using the printing process was confirmed. This temperature sensor was able to track the heat source and check the distribution process through which heat is transferred. Therefore, it can be expected to be used in fields that require temperature monitoring.
Display omitted
•Grid-type thin-film temperature sensors have been proposed.•The sensors were fabricated to evaluate the temperature distribution•The optimal conditions for printing and manufacturing sensors determined.•The heating source can be easily detected using the sensors.•Visualization data showing the heat distribution are presented with time.
Active and durable electrocatalysts for methanol oxidation reaction are of critical importance to the commercial viability of direct methanol fuel cell technology. Unfortunately, current methanol ...oxidation electrocatalysts fall far short of expectations and suffer from rapid activity degradation. Here we report platinum-nickel hydroxide-graphene ternary hybrids as a possible solution to this long-standing issue. The incorporation of highly defective nickel hydroxide nanostructures is believed to play the decisive role in promoting the dissociative adsorption of water molecules and subsequent oxidative removal of carbonaceous poison on neighbouring platinum sites. As a result, the ternary hybrids exhibit exceptional activity and durability towards efficient methanol oxidation reaction. Under periodic reactivations, the hybrids can endure at least 500,000 s with negligible activity loss, which is, to the best of our knowledge, two to three orders of magnitude longer than all available electrocatalysts.
This study aimed to confirm the presence of gingival inflammation through image analysis of the papillary gingiva using intra-oral photographs (IOPs) before and after orthodontic treatment and to ...confirm the possibility of using gingival image analysis for gingivitis screening. Five hundred and eighty-eight (n = 588) gingival sites from the IOPs of 98 patients were included. Twenty-five participants who had completed their orthodontic treatments and were aged between 20 and 37 were included. Six points on the papillary gingiva were selected in the maxillary and mandibular anterior incisors. The red/green (R/G) ratio values were obtained for the selected gingival images and the modified gingival index (GI) was compared. The change in the R/G values during the orthodontic treatment period appeared in the order of before orthodontic treatment (BO), mid-point of orthodontic treatment (MO), three-quarters of the way through orthodontic treatment (TO), and immediately after debonding (IDO), confirming that it was similar to the change in the GI. The R/G value of the gingiva in the image correlated with the GI. Therefore, it could be used as a major index for gingivitis diagnosis using images.
Azomethine diols (AMDs) were synthesized by condensation between a terephthalic aldehyde, polyether diamine, and ethanol amine. The synthesized AMDs were employed to introduce azomethine groups into ...the backbones of polyurethane elastomers (PUEs). Different AMDs were designed to control the concentration and distribution of azomethine groups in PUEs. In this study, we explored the intrinsic self-healing of AMD-based PUEs by azomethine metathesis. Particularly, the effects of the concentration and distribution of the azomethine groups on the AMD-based PUEs were considered. Consequently, as the azomethine group concentration increased and the distribution became denser, the self-healing properties improved. With AMD3-40, the self-healing efficiency reached 86% at 130 °C after 30 min. This represents a 150% improvement over the control PUE. Additionally, as the AMD content increased, the mechanical properties improved. With AMD3-40, the tensile strength reached 50 MPa. Therefore, we concluded that the self-healing and mechanical properties of PUEs can potentially be tailored for applications by adjusting the concentration and design of AMD structure for PUEs.
Polyurethane (PU) is a versatile polymer used in a wide range of applications. Recently, imparting PU with self-healing properties has attracted much interest to improve the product durability. The ...self-healing mechanism conceivably occurs through the existence of dynamic reversible bonds over a specific temperature range. The present study investigates the self-healing properties of 1,4:3,6-dianhydrohexitol-based PUs prepared from a prepolymer of poly(tetra-methylene ether glycol) and 4,4'-methylenebis(phenyl isocyanate) with different chain extenders (isosorbide or isomannide). PU with the conventional chain extender 1,4-butanediol was prepared for comparison. The urethane bonds in 1,4:3,6-dianhydrohexitol-based PUs were thermally reversible (as confirmed by the generation of isocyanate peaks observed by Fourier transform infrared spectroscopy) at mildly elevated temperatures and the PUs showed good mechanical properties. Especially the isosorbide-based polyurethane showed potential self-healing ability under mild heat treatment, as observed in reprocessing tests. It is inferred that isosorbide, bio-based bicyclic diol, can be employed as an efficient chain extender of polyurethane prepolymers to improve self-healing properties of polyurethane elastomers via reversible features of the urethane bonds.
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