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Rear-foot-elevated split squat (RFESS) is often performed as an alternative to conventional double-leg back squat (DLBS). This study aimed to compare 3-dimensional joint kinetics of DLBS and RFESS using the same relative intensity of loads. Eight male college rugby players performed 3 repetitions of DLBS and RFESS at 10-repetition-maximum (RM) loading. Before testing, both exercises were incorporated into the subjects’ training program with a progressive increase in loads for 4 months. A 3-dimensional optical motion capture system and force platform were used for data collection. The 3-dimensional moments at the knee and hip joints in each of the 3 axes were calculated based on the inverse dynamic procedure. p values < 0.05 were considered statistically significant. The hip extension moment was 44% greater in the RFESS than in the DLBS at the bottom position (p < 0.01) and 47% greater for the peak value (p < 0.01) on harmonic averages. The hip abduction and external rotation moments at the bottom position were also greater in the RFESS than in the DLBS. The findings suggest that the magnitude of hip extension moment per leg in DLBS tends to be restricted to less than that expected from the given strength level. In conclusion, the mechanical contribution of hip extensors per leg can be greater in RFESS than in DLBS when using respective 10RM loads, even if the absolute load is smaller and the trunk is more upright in RFESS. [ABSTRACT FROM AUTHOR]

Flexible-robust metal-organic frameworks (MOFs), which exhibit unique hybrid nature comprising both flexible and rigid framework characteristics, exhibit high potential for hydrocarbon separations. However, no clear guidelines have been established to regulate their hybrid characteristics owing to limited understanding of their adsorption mechanism. This study investigates the effects of the particle size of a flexible-robust MOF on its adsorption and structural transition behaviors. The robust nature originates from the structural transition of a metastable guest-free structure, while its flexible nature arises from another guest-free structure. The type of guest-free structure is predominantly determined by the particle size; particles below the critical size are trapped in the metastable guest-free structure. Notably, the critical size varies with the type of guest molecule to be removed; consequently, the difference in critical size results in guest-memory characteristics, enabling guest-free structure switching. These results underscore the importance of controlling the particle size to fine-tune hybrid adsorption characteristics of flexible-robust MOFs. [ABSTRACT FROM AUTHOR]

Azobenzene-containing block copolymers have been previously developed as light-induced reworkable adhesives that can undergo repeatable bonding/debonding on demand, based on photoisomerization of the azobenzene moiety and concomitant softening/hardening of the azo polymer block. For practical use, the applicability of such adhesives to various types of substrates is important and is thus studied as one of their most fundamental properties in this work. Ultraviolet (UV)-transparent acrylic resin as well as non-transparent polycarbonate resin, polyethylene ones, and metallic aluminum substrates are utilized as substrates. UV-transparent acrylic resin is used as one of two substrates to investigate the photoisomerization process. The bonding/debonding process is successful for these substrates, and single lap shear tests show typical adhesion strengths of 1.5-2.0 MPa for the substrates investigated. UV irradiation induced a decrease in the adhesion strength to 0.03 MPa irrespective of the substrate type, indicating that the mechanism of the detachability is flow of the softened adhesive. Facile removal of the residual adhesive on the substrate is successfully demonstrated after detachment without any damage to the substrates by wiping the substrate with laboratory-grade disposable wipes wet with ethanol. [ABSTRACT FROM AUTHOR]

Male sterility is one of the reproductive isolation systems in plants and quite useful for F1 seed production. We previously identified three independent quantitative trait loci (QTLs) for male sterility of cultivated strawberry, Here, we identified the specific subgenomes in which these QTLs are located by QTL-seq approach. QTLs qMS4.1, qMS4.2, and qMS4.3 were mapped separately in subgenomes Fvb4-4, Fvb4-3, and Fvb4-1, respectively, in 'Camarosa' genome assembly v. 1.0.a1. Candidate regions of qMS4.1 and qMS4.3 were clearly detected around 12-26 Mb in Fvb4-4 and 12-14 Mb in Fvb4-1, respectively; those of qMS4.2 were fragmented in Fvb4-3, which suggests that some scaffolds were incorrectly assembled in Fvb4-3. qMS4.3 was mapped to chr4X1 of 'Reikou' genome assembly r2.3, and qMS4.1 and qMS4.2 were both mapped to chr4Av, which indicates that differentiation of the subgenomes in which both QTLs are located was insufficient in 'Reikou' r2.3. Although 'Camarosa' genome assembly v. 1.0.a1 is an unphased map, which merges homologous chromosomes into one sequence, 'Reikou' genome assembly r2.3 is a phased map, which separates homologous chromosomes. QTL mapping to different reference genomes clearly showed the specific features of each reference genome, and that using different kinds of reference map could accelerate fine mapping and map-based cloning of certain genes of cultivated strawberry. [ABSTRACT FROM AUTHOR]

Fruit shape of cultivated strawberry (Fragaria × ananassa Duch.) is an important breeding target. To detect genomic regions associated with this trait, its quantitative evaluation is needed. Previously we created a multi-parent advanced-generation inter-cross (MAGIC) strawberry population derived from six founder parents. In this study, we used this population to quantify fruit shape. Elliptic Fourier descriptors (EFDs) were generated from 2 969 two-dimensional binarized fruit images, and principal component (PC) scores were calculated on the basis of the EFD coefficients. PC1-PC3 explained 96% of variation in shape and thus adequately quantified it. In genome-wide association study, the PC scores were used as phenotypes. Genome wide association study using mixed linear models revealed 2 quantitative trait loci (QTLs) for fruit shape. Our results provide a novel and effective method to analyze strawberry fruit morphology; the detected QTLs and presented method can support marker-assisted selection in practical breeding programs to improve fruit shape. [ABSTRACT FROM AUTHOR]

A strawberry Multi-parent Advanced Generation Intercrosses (MAGIC) population, derived from crosses using six strawberry cultivars was successfully developed. The population was composed of 338 individuals; genome conformation was evaluated by expressed sequence tag-derived simple short repeat (EST-SSR) markers. Cluster analysis and principal component analysis (PCA) based on EST-SSR marker polymorphisms revealed that the MAGIC population was a mosaic of the six founder cultivars and covered the genomic regions of the six founders evenly. Fruit quality related traits, including days to flowering (DTF), fruit weight (FW), fruit firmness (FF), fruit color (FC), soluble solid content (SC), and titratable acidity (TA), of the MAGIC population were evaluated over two years. All traits showed normal transgressive segregation beyond the founder cultivars and most traits, except for DTF, distributed normally. FC exhibited the highest correlation coefficient overall and was distributed normally regardless of differences in DTF, FW, FF, SC, and TA. These facts were supported by PCA using fruit quality related values as explanatory variables, suggesting that major genetic factors, which are not influenced by fluctuations in other fruit traits, could control the distribution of FC. This MAGIC population is a promising resource for genome-wide association studies and genomic selection for efficient strawberry breeding. [ABSTRACT FROM AUTHOR]