Chiba Institute of Technology

Background: Extracellular vesicles (EVs) released from skeletal muscle mediate metabolic communication via microRNAs (miRNAs). While both circadian rhythms and exercise influence metabolism, the joint modulation of the muscle-derived EV miRNA landscape by circadian rhythms and chronic exercise remains undefined, particularly under the metabolic stress of obesity. Methods: Employing a 2 × 2 factorial design (Phase: ZT3 vs. ZT15; Condition: sedentary vs. exercise; ZT, Zeitgeber Time), EV-enriched fractions were isolated from ex vivo quadriceps muscle (QUA) cultures of high-fat diet-fed mice following an 8-week treadmill training regimen using polymer-based precipitation, and comprehensive miRNA profiling was performed by small RNA sequencing. Results: Principal component analysis (PCA) revealed that circadian phase accounted for a greater proportion of global variance in EV miRNA profiles than exercise. Differential expression analysis identified miR-1a-3p and miR-1b-5p as upregulated across both composite phase and exercise contrasts; however, condition-specific analyses indicated that this signal was primarily driven by the sedentary-phase comparison (ZT15-sed vs. ZT3-sed), in which the miR-29 family was also prominently co-upregulated, rather than constituting independent phase and exercise effects; this phase-associated signature was absent in the corresponding exercise-condition comparison. Exploratory functional enrichment of experimentally validated targets revealed phase-preferential association with metabolic and iron-heme pathways, whereas exercise-associated miRNAs mapped to signaling, inflammatory, and transcription-related networks. Conclusions: Circadian phase was the dominant contributor to global variance in muscle-derived EV-enriched miRNA profiles in obesity, as reflected by the phase-associated separation along principal component 1 (PC1, 33.47% of total variance), with exercise introducing context-dependent adaptive modulation. This study provides a foundational basis for investigating the temporal regulation of muscle secretome dynamics under high-fat diet conditions, highlighting temporal specificity as a key dimension in EV-mediated exercise physiology research.

Abstract We conducted a two-band imaging survey observation using the Subaru Telescope and its wide-field camera, Suprime-Cam, to study the visible colors and size distribution of Jupiter’s Trojan asteroids. The survey covered an area around Jupiter’s L4 Lagrange point totaling 9.2 square degrees. We detected 120 Trojan asteroids in this survey. From these Trojan asteroids, we extracted 44 unbiased samples with absolute magnitudes in the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>g</mml:mi> <mml:mo accent="false">′</mml:mo> </mml:math> band ranging from 12.9 to 16.9 mag (corresponding to diameter ranges of approximately ∼3–16 km assuming an albedo of 0.05) and analyzed their <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>g</mml:mi> <mml:mo accent="false">′</mml:mo> <mml:mo>−</mml:mo> <mml:mi>i</mml:mi> <mml:mo accent="false">′</mml:mo> </mml:math> color and size distributions. Large Jupiter Trojan asteroids are known to be classified into two color groups, “red” and “less red.” We found that such bimodality in the color distribution is absent for small Jupiter Trojan asteroids, which is consistent with previous studies. Previous studies have also shown that these two groups have different slopes in the magnitude distributions from each other, which was explained by conversion of red objects to less-red fragments through catastrophic disruptions. In contrast, we found that the size frequency distributions of our two sample groups divided by the color of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>g</mml:mi> <mml:mo accent="false">′</mml:mo> <mml:mo>−</mml:mo> <mml:mi>i</mml:mi> <mml:mo accent="false">′</mml:mo> </mml:math> = 0.7 (in AB magnitude) are quite similar. Our results can provide new insights into collisional evolution of color and size distribution of small Jupiter Trojans.

Antisense oligonucleotides (ASOs) are nucleic acid therapeutics that regulate gene expression through sequence-specific hybridization with target RNA. Under physiological conditions, many target RNAs adopt higher-order structures, which can strongly influence ASO accessibility and binding behavior. Although UV melting analysis is widely used to evaluate the thermal stability of ASO/RNA duplexes, this approach does not adequately account for the structural features of target RNAs. In this study, we investigated the utility of surface plasmon resonance (SPR) analysis as an in vitro method to evaluate ASO binding while considering RNA structural constraints. Multiple ASOs were designed to target PRF84, an 84-nucleotide RNA motif that induces −1 programmed ribosomal frameshifting in HIV-1 gag-pol expression. SPR analyses were performed to compare ASO interactions with complementary RNA fragments and with structurally folded PRF84. The results demonstrated that identical ASOs exhibited distinct binding behaviors depending on whether the target was a complementary RNA or PRF84, indicating that RNA structure significantly affects ASO binding. These findings suggest that SPR analysis enables the evaluation of ASO–RNA interactions taking structure into account, and may be a useful alternative approach to conventional UV melting analysis-based ASO screening.

Attention-deficit/hyperactivity disorder (ADHD) often emerges in early childhood; however, objective validated biomarkers for its early detection remain limited. In this study, we aimed to identify pupil-based candidate physiological markers (i.e., physiological correlates) associated with ADHD-related traits in preschool- and early school-aged children. To this end, we recorded the pupil diameters of typically developing children without an ADHD diagnosis during a simple fixation task. From these data, we extracted multiple features, including the mean pupil size, temporal variability, and interocular asymmetry in both magnitude and variability. ADHD-related tendencies were assessed using the ADHD Rating Scale-5. Among the features analyzed, only the temporal variability of interocular asymmetry (VarLRdiff) showed a significant positive correlation with ADHD Rating Scale-5 total and subscale scores. This association likely reflects the combined effects of immature autonomic regulation and functional asymmetry in the neural circuits involving the locus coeruleus. In contrast, other pupil-based indices showed no significant correlations, potentially because of developmental ceiling effects and the short evaluation duration. These findings suggest that VarLRdiff may serve as a promising candidate physiological marker of ADHD-related traits in young children, requiring further validation. Future studies incorporating longer recordings, advanced analytical methods, and evaluation of test–retest stability, as well as longitudinal follow-up, are warranted to evaluate its potential utility for early screening, pending clinical and longitudinal validation.

Abstract Observations of exoplanet transits by small satellites have gained increasing attention for reducing biases in the detection of long-period planets. However, no unambiguous detection of an exoplanet has yet been demonstrated using optics with apertures smaller than 60 mm. Here, we investigated the detectability of exoplanet transits using the telescopic Optical Navigation Camera (ONC-T) on board the Hayabusa2 spacecraft, which has an effective aperture of only 15 mm. We conducted transit observations of the hot Jupiters WASP-189 b and MASCARA-1 b, collecting data for 10 and four events, respectively. The transit signal was detected with a signal-to-noise ratio (SNR) of 13 for WASP-189 b and 8 for MASCARA-1 b for each event. Stacking all events improved the SNR to 40 and 16, respectively. The transit midtimes of each event were measured with a precision of 6 minutes and were consistent with Transiting Exoplanet Survey Satellite (TESS) data to within 2 minutes. The planet-to-star radius ratio was determined with an absolute precision of 0.004 (6% relative) and agreed with TESS results to within 0.002 (3% relative). The recent ONC-T and TESS data enabled an update to the planetary ephemerides. We report a 4 σ discrepancy between the updated orbital period of MASCARA-1 b and previously reported values. ONC-T sets a new record for the smallest-aperture instrument to detect an exoplanet transit from space, advancing the frontier of exoplanet science with miniature instrumentation. Our results suggest that optics as small as ONC-T may be capable of detecting transiting long-period Jupiters: a population that remains underrepresented in current surveys.

ABSTRACT In Upper Mesopotamia, the transition from the Pre‐Pottery Neolithic A (PPNA) to Pre‐Pottery Neolithic B (PPNB) period, ca. 10 800–10 600 cal. BP, is marked by a series of changes in chipped stone industries, architectural forms, symbolic objects, regional distribution of settlements and long‐distance exchange networks among others. These shifts may indicate rapid social transformations occurring in this time period. Since settlement size and layout can serve as proxies for population scale and social structure, methodologies capable of capturing entire site plans are critical. Geophysical prospection provides an efficient means for surveying entire archaeological sites, making it particularly suitable for studying settlement size and layout. However, geophysical prospection of Pre‐Pottery Neolithic sites in Upper Mesopotamia has rarely been published. This study conducted comprehensive geophysical investigations, including topographic survey, magnetometry and ground‐penetrating radar, covering the entire mound of Harbetsuvan Tepesi, a recently discovered small‐scale (approximately 5900 m 2 ) Early PPNB site in southeastern Anatolia. This represents the first comprehensive geophysical survey covering the entire extent of a PPNB site in this region. The data revealed a cluster of rectangular rooms densely concentrated near the mound's centre, with no indication of large open spaces or significantly oversized monumental structures. This settlement layout differs from larger contemporary sites in the region, where large circular monumental buildings have been exposed alongside clustered small dwellings. This settlement layout at Harbetsuvan Tepesi provides an example of the social structure of small settlements and makes a contribution to understanding the inter‐site regional social hierarchies and settlement diversity during the PPNA–PPNB transition.

Coarse-to-fine partitioning (CFP) algorithm is proposed for angle-of-arrival (AoA) estimation with controllable liquid crystal display (LCD) in front of a photodetector (PD). By electrically switching each pixel of the LCD in transparent or opaque, the position of the aperture through which the incident light passes is controlled to estimate the AoA of the incident light to the PD. The size of the aperture needs to be a certain size to maintain the accuracy of the AoA estimation, which consists of a region of several pixels. In the conventional algorithm, with a fixed size of the aperture equal to the size of resolution unit, the entire surface of the LCD was exhaustively searched horizontally and vertically. In our CFP algorithm, the entire surface is partitioned into two or three equal-area regions, and the intensities observed at the PD when pixels consisting of each of such regions are alternately switched to transparent mode are compared. Among them, the region with the highest intensity observed is chosen as the next candidate region through which the incident light passes. This process is iteratively applied, partitioning the candidate region from coarse to fine, until the region reaches the resolution size. For the LCD consisting of 2560×1440 pixels with the resolution unit size of 10×10 pixels, to estimate the AoA, our CFP algorithm requires 30searches while the conventional algorithm requires 400searches. Experimental results show that although intensity measurements are repeated fifteen times for each search to stabilize the intensity measurement values in both of the conventional algorithm and our CFP algorithm, our algorithm estimates it with the error less than one degree. Furthermore, by adding another PD into the system, from the AoA estimation for the two PDs with our CFP algorithm, the distance estimation to the light source from 200mm to 900mm is experimentally shown with a relative error of 4.5%.

Abstract InGaN power converters, which can absorb near-ultraviolet light with a low attenuation coefficient in water, are expected to be used for underwater optical wireless power transmission. To improve photovoltaic conversion efficiency under high-power near-ultraviolet laser illumination, we fabricated InGaN converter cells with Pd/Pt electrodes, grown on a GaN substrate instead of a sapphire substrate. We investigated the dependence of laser power, temperature, and laser wavelength. As a result, the InGaN converter cell showed a photovoltaic conversion efficiency of 26.4% under 394 nm laser light (16 mW/cm2) at 25°C and 20.2% under 395 nm laser light (3.15 W/cm2) at 80°C. To further improve the efficiency of InGaN converter cells under high-power laser irradiation, it was found that three key issues must be overcome: reducing the dislocation density, lowering the electrical resistivity of the surface layer, and increasing the thickness of the optical absorption layer.