Transversely graded polarization volume gratings fabricated by freeform holographic photoalignment.

Polarization volume gratings (PVGs) based on chiral nematic liquid crystals offer a great potential as polarization-dependent holographic optical elements, but it is not easy to fabricate PVGs with varying pattern periods in the transverse plane. Here, we fabricate a PVG with an in-plane gradient of the pattern period by performing two-beam interference photoalignment on a flexible polyimide substrate. The pattern period varies depending on the local interference angle, which is controlled by the bent shape of the flexible substrate. We demonstrate fabrication of a PVG with a linearly graded sub-micrometer period, showing the potential of the proposed method to fabricate designer PVGs.

The relevance of figure-of-eight walk test to hip muscle strength in healthy young males.

[Purpose] This study aimed to investigate the contribution of hip muscle torque to figure-of-eight walk (F8W) test in healthy young males. [Participants and Methods] Twenty healthy young males (40 limbs; mean age, 21.7 ± 0.6 years) participated. We measured the maximum F8W speed and steps. The hip muscle strengths (MS) of the flexor, extensor, abductor, and adductor muscles as well as the internal and external rotators (ER) were measured using a handheld belt-stabilized dynamometer. The hip muscle torque to weight-bearing index (WBI) is expressed as the measured MS divided by the lower thigh or shin length and body weight. [Results] F8W-time and F8W-rate were relevant to the ER-WBI (F8W time: ß=-0.330; F8W rate: ß=0.369). [Conclusion] This study's findings suggest that hip ER strength contributes to F8W in healthy young males.

Detailed clinical features and genotype-phenotype correlation in an OTOF-related hearing loss cohort in Japan.

Mutations in the OTOF gene are a common cause of hereditary hearing loss and the main cause of auditory neuropathy spectrum disorder (ANSD). Although it is reported that most of the patients with OTOF mutations have stable, congenital or prelingual onset severe-to-profound hearing loss, some patients show atypical clinical phenotypes, and the genotype-phenotype correlation in patients with OTOF mutations is not yet fully understood. In this study, we aimed to reveal detailed clinical characteristics of OTOF-related hearing loss patients and the genotype-phenotype correlation. Detailed clinical information was available for 64 patients in our database who were diagnosed with OTOF-related hearing loss. As reported previously, most of the patients (90.6%) showed a "typical" phenotype; prelingual and severe-to-profound hearing loss. Forty-seven patients (73.4%) underwent cochlear implantation surgery and showed successful outcomes; approximately 85-90% of the patients showed a hearing level of 20-39 dB with cochlear implant and a Categories of Auditory Performance (CAP) scale level 6 or better. Although truncating mutations and p.Arg1939Gln were clearly related to severe phenotype, almost half of the patients with one or more non-truncating mutations showed mild-to-moderate hearing loss. Notably, patients with p.His513Arg, p.Ile1573Thr and p.Glu1910Lys showed "true" auditory neuropathy-like clinical characteristics. In this study, we have clarified genotype-phenotype correlation and efficacy of cochlear implantation for OTOF-related hearing loss patients in the biggest cohort studied to date. We believe that the clinical characteristics and genotype-phenotype correlation found in this study will support preoperative counseling and appropriate intervention for OTOF-related hearing loss patients.

Association between generalized joint laxity and knee joint movement in female university students.

[Purpose] This study investigated the association between generalized joint laxity and knee joint movement in female university students. [Participants and Methods] The study included 21 female university students. Generalized joint laxity was measured using the Beighton criteria for joint hypermobility. Acceleration and angular velocities of the tibia during knee extension were measured along three axes using a triaxial accelerometer. Sampling data were expressed as root mean squares. The Mann-Whitney U test was used to determine differences in the acceleration and angular velocities along each axis between the generalized joint laxity and non-generalized joint laxity groups. Spearman's rank correlations were used to confirm the association between these parameters. [Results] The rotational angular velocity was greater in the generalized joint laxity than in the non-generalized joint laxity group, and we observed a significant correlation between Beighton scores and the X-axis angular velocity. Furthermore, rotational angular velocity was positively correlated with anterior-posterior acceleration and extension angular velocity. [Conclusion] These findings suggest that rotational angular velocity of the tibia during knee extension is associated with generalized joint laxity in female university students.

Relationship between single-leg stance test with light touch and hip muscle strength in healthy young adults.

[Purpose] This study investigated the relationship between the single-leg stance test with light touch and hip rotator muscle strength. [Participants and Methods] Thirty-one healthy young adults participated in the study. A single leg stance test with light touch was performed to evaluate the participants' static balance ability. The duration that an individual could successfully perform the single leg stance test with light touch in the eyes open was measured. The participants were instructed to slightly touch their right index fingertip on the digital scale. The hip muscle strength of the internal rotators and external rotators were measured by the isometric peak torque. The internal/external rotator strength ratio was calculated by dividing the strength of the internal rotator by that of the external rotator. [Results] The hip external rotator muscle strength was higher in males than in females. Moreover, there was a significant correlation between the single-leg stance test with light touch and hip external rotator muscle strength in males and between the single leg stance test with light touch and hip internal rotator muscle strength in females. Furthermore, a significant positive correlation was found between the single leg stance test with light touch and hip internal rotator/external rotator ratio in males. [Conclusion] We concluded that the single leg stance test with light touch is a useful tool to evaluate static hip muscle strength.

Comparison of spinal column alignment and autonomic nervous activity using the intersegmental tenderness test in the segment above.

[Purpose] The thoracolumbar supraspinous intersegmental tenderness test (ITT) in the segment above was performed to compare spinal alignment and autonomic activity in the presence or absence of pain. [Participants and Methods] Thirty young males were grouped into Th1-4 (Cardiopulmonary visceral nerves), Th5-9 (Large visceral nerve), and Th10-12 (Small visceral nerve) by ITT for the presence of pain. Measurements of the spinal alignment and autonomic function were performed. [Results] Those with ITT pain had a significantly lower range of motion in the sagittal plane at Th12, Th12-L1, and L2-3 and in the frontal plane at Th1-2, Th4-5, Th6-7, and L3-4 than those in the no pain group. On autonomic function tests, the pain group had significantly lower Total Power, LF (Low Frequency), and CVRR (Coefficient of variation of R-R interval). [Conclusion] In ITT, patients with pain at Th5-9 have a mixture of reduced sagittal tilt angle and autonomic hypofunction of the adjacent upper and lower thoracic to lumbar vertebrae.

Effects of short-term immobilization of the upper limb on the somatosensory pathway: a study of short-latency somatosensory evoked potentials.

[Purpose] Previous studies have reported that the nervous system is influenced during short-term cast immobilization. However, the effects of short-term inactivity on somatosensory information processing systems are not well understood. This study investigated the effect of 10 h of upper limb immobilization on the somatosensory pathway using short-latency somatosensory evoked potentials. [Participants and Methods] Twenty right-handed healthy participants (mean age 21.7 years) were enrolled in this study. The participants' left hands and forearms were wrapped in a soft bandage at a 90° elbow flexed position. The participants were instructed not to move their left hand for 10 h. To obtain short-latency somatosensory evoked potentials, we used a multimodal evoked potential system. The left median nerve was electrically stimulated at a rate of 5 Hz for a duration of 0.2 ms. The intensity of the stimulus was adjusted to induce mild twitches of the thumb. The amplitudes and latencies of the short-latency somatosensory evoked potential components (N9, N13, and N20) were measured before and after immobilization. [Results] The amplitude of the N9 component significantly increased after immobilization. [Conclusion] Our results indicated that the changes in the excitability of the peripheral somatosensory nerve were due to 10 h of inactivity.

A path analysis of the interdependent relationships between life space assessment scores and relevant factors in an elderly Japanese community.

[Purpose] This study aimed to examine the direct and indirect effects of factors influencing the risk of life space assessment using path analysis. [Participants and Methods] A sample of 212 elderly residents (at least 65 years old) with no clear indications of cognitive dysfunction, visual impairment, and physical dysfunction were recruited for the study. Data on these factors were collected from the participants at a community gathering using measures of life space assessment, skeletal muscle mass, lower extremity muscle strength, mobility, cognitive function, and fear of falling. Correlational and path analyses were used to investigate the relationships between these variables. [Results] The final path model satisfied the requisite statistical criteria, and subsequently, the relationships between the physiological and psychological factors associated with life space assessment were structured and represented visually. Age, skeletal muscle mass, fear of falling, and mobility had a direct effect on life space assessment, whereas lower extremity muscle strength and cognitive function affected it indirectly. [Conclusion] In this study, direct and indirect effects of physiological and psychological factors related to risk of life space assessment of the elderly were clarified using path analysis.

Effect of limbering up of the muscles attached to the pelvis on the strength of upper and lower extremity and trunk muscles through the transitional network.

[Purpose] To study the effect that limbering up of the muscles attached to the pelvis has on muscle strength of the trunk and upper and lower extremities, which are not being exercised, and to investigate the possibilities for clinical application. [Subjects and Methods] A total of 152 healthy adult men. Sthenometry was conducted using a handheld dynamometer to assess the effect of limbering up of the upper gluteus maximus, hamstrings, and internal abdominal oblique muscles attached to thoracolumbar fascia on the trunk and upper and lower extremities. The exercises were slowly performed 20 repetitions. Subjects were divided into AB group (n=49) measuring abdominal and back muscle strength, K group (n=42) measuring knee flexor and extensor strength, and S group (n=61) measuring shoulder flexor and external rotator strength and compared to non-exercising controls. [Results] In the exercise groups, exercising either gluteus maximus or hamstrings significantly increased the strength of abdominal and back muscles; exercising gluteus maximus increased knee extensor strength, and exercising the abdominal internal oblique muscle significantly increased knee flexor strength; and shoulder flexor strength significantly increased after exercising gluteus maximus versus controls. [Conclusion] This may be useful in rehabilitation of injuries to the trunk and upper and lower extremities.

Growth of the Coconut Crab, Birgus latro, at Its Northernmost Range Estimated from Mark-Recapture Using Individual Identification Based on Carapace Grooving Patterns.

Although populations of the coconut crab, Birgus latro, have declined in the tropical Indo-Pacific region, insufficient knowledge exists for the management of this species. We investigated the growth of the northernmost coconut crab population, located at Ocean Expo Park, Okinawa, southern Japan, using a mark-recapture method based on the identification of individual carapace grooving patterns. Of the 485 crabs photographed (264 males, 221 females; 14.3-68.8 mm thoracic length [ThL]), 64 males and 62 females were recaptured (recapture rate 26%). The liberty period ranged from two to 2384 days. The annual data indicated that most crabs molted during winter, except for juveniles and crabs near the maximum size. Using the GROTAG program, the asymptotic ThL (L∞) was estimated as 80.72 and 49.89 mm for males and females, respectively. The Brody growth coefficient (K) was 0.063 for both sexes. The growth curves from these parameters showed that males grew larger than females because of a difference in growth speed. Longevity was estimated at approximately 50 years for both sexes. The growth data obtained in the present study, which are the most precise gathered for the coconut crab to date, can be compared with the results of studies performed in other regions.

The Control of Postural Stability during Standing is Decreased in Stroke Patients during Active Head Rotation.

[Purpose] The aim of this study was to evaluate the effect of active head rotation on postural control in stroke patients during standing as compared with age-matched healthy subjects. [Subjects and Methods] In total, 46 stroke patients and 37 age-matched healthy subjects were recruited for the study. A stabilometer was used to assess postural stability in participants during standing, with or without active head rotation, and with their eyes open or closed. Subjects were asked to stand on a force plate while rotating their head in the yaw plane at a frequency of 1.0 Hz. A metronome was used to maintain the head rotation frequency, and the head rotation range was maintained at a total of 70° during the postural stability examinations. [Results] The control of postural stability during standing with active head rotation was significantly decreased in the stroke group as compared with the healthy group with both the eyes open and closed. No significant differences in relation to standing without head motion were observed between groups. [Conclusion] The findings suggest that postural instability is increased in stroke patients during active head rotation, and therefore, vestibular function in relation to head rotation might be reduced in stroke patients.

Gene expression of cytokines and prostaglandin metabolism-related proteins in eosinophilic otitis media.

The objective of this study was to investigate the levels of gene expression in the middle ear mucosa of 2 patients diagnosed with eosinophilic otitis media. One patient with severe hearing loss showed high expression levels of genes encoding IL-5 and IL-33 receptors.

A Standing Low-frequency Vibration Exercise Device for Improving Balance in Community-dwelling Older Adults: A Single-blind Randomized Controlled Trial.

OBJECTIVE: This study aimed to compare the effects of the standing low-frequency vibration exercise device (SLVED) and walking training on balance ability on an unstable surface in community-dwelling elderly people. METHODS: Thirty-eight older adults were randomly allocated to the SLVED sessions: the intervention group (n = 19), and the walking sessions: the control group (n = 19). Each group session lasted 20 min and was performed twice a week for 12 weeks. Standing balance was assessed by the change in center-of-gravity sway of the participant standing on foam rubber with eyes open (EO) and eyes closed (EC). The primary outcome measures were the root mean square (RMS) values of the center of foot pressure in the mediolateral and anteroposterior directions and the RMS area. Secondary outcome measures were the results of the 10-m walking time test (10 MWT), five-times sit-to-stand (5T-STS) test, and timed up-and-go (TUG) test. RESULTS: Analysis of variance showed a significant group × time interaction for the TUG test. Significant improvements were observed in Y-RMS for EO condition; RMS, X-RMS, Y-RMS, and RMS area for EC condition; and 10 MWT, 5T-STS test, and TUG test for the main effect of the time factor. CONCLUSION: SLVED for intervention in community-dwelling older adults showed a greater improvement than walking training in the TUG test. In addition, SLVED improved the Y-RMS for the EO condition on foam rubber; RMS, X-RMS, Y-RMS, and RMS area for the EC condition on foam rubber in standing balance; and the 10 MWT and 5T-STS test, suggesting that it has similar effects to walking training.

Short-Term Cast Immobilization of a Unilateral Lower Extremity and Physical Inactivity Induce Postural Instability during Standing in Healthy Young Men.

Previous studies have reported an increased postural sway after short-term unilateral lower limb movement restriction, even in healthy subjects. However, the associations of motion limitation have not been fully established. The question of whether short-term lower limb physical inactivity and movement restriction affect postural control in the upright position remains. One lower limb of each participant was fixed with a soft bandage and medical splint for 10 h while the participant sat on a manual wheelchair. The participants were instructed to stand still for 60 s under eyes-open (EO) and eyes-closed (EC) conditions. Using a single force plate signal, we measured the center of pressure (COP) signal in the horizontal plane and calculated the total, anterior-posterior (A-P), and medial-lateral (M-L) path lengths, sway area, and mean COP displacements in A-P and M-L directions. The COP sway increased and the COP position during the upright stance shifted from the fixed to the non-fixed side after cast removal, compared to before the cast application, under both EO and EC conditions. These findings indicated that 10 h of unilateral lower limb movement restriction induced postural instability and postural control asymmetry, suggesting the acute adverse effects of cast immobilization.

Collection of environmental DNA from stemflow for monitoring arboreal biodiversity: Preliminary validation using lichens.

The forest canopy harbors a diverse array of organisms. However, monitoring their biodiversity poses challenges due to limited accessibility and the vast taxonomic diversity. To address these challenges, we present a novel method for capturing arboreal biodiversity by harnessing stemflow as a source of DNA from organisms inhabiting trees. Our method involves encircling the tree trunk with gauze, directing the stemflow along the gauze into a funnel, and collecting it in a plastic bag. We employed dual collection systems to retrieve environmental DNA (eDNA) from the stemflow: the gauze trap, designed to capture macroscopic biological fragments, and the plastic bag trap, which collected the stemflow itself. The trapped fragments and stemflow were separately filtered, and eDNA was subsequently extracted from the filter membranes. To validate our method, we focused on foliose lichens, which are easily observable on tree surfaces. We performed eDNA metabarcoding and successfully detected a majority of the observed foliose lichen species, including those not identified through visual observation alone.•We have developed a non-invasive and straightforward method for monitoring arboreal biodiversity by collecting eDNA from stemflow, which has been validated using lichens for its efficacy.•This cost-effective approach minimizes disruptions to tree ecosystems and is expected to provide an efficient means of sampling and monitoring arboreal organisms.

Quadrupedal Walking with the Skin: The Ambulatory Flaps in "Walking" Cuttlefish (Paintpot Cuttlefish, Metasepia tullbergi).

AbstractThe locomotion strategy of cephalopods is an important factor that influences their ability to exploit various oceanic environments. Particularly, Metasepia cuttlefish have a unique locomotion strategy; they prefer slow walking (ambling) on the seafloor over swimming. For this locomotion, they use their ventral arms as forelimbs and ambulatory flaps as hindlimbs. This locomotion is similar to the gait of quadruped vertebrates, where the forelimbs and hindlimbs on the left and right move alternately. The original description and some textbooks have considered these flaps to be muscular; however, this has not been proven. Here, we report the histological morphology of the ambulatory flaps of Metasepia tullbergi and their ambling locomotion. Histological observations indicated that the ambulatory flaps had a papillae structure comprising papillae musculature (dermal erector or retractor muscles) and connective tissue in the skin. Behavioral observations indicated that the ambulatory flaps changed their shape during ambling, which could explain the existence of the skin papillae. Our results suggest that ambulatory flaps are skin papillae, which can change shape by using their papillae musculature and connective tissue. This is a unique feature of Metasepia species that use the skin papillae for locomotion.

Gravity filtration of environmental DNA: A simple, fast, and power-free method.

Filtration is required during the collection of trace amounts of environmental DNA (eDNA) from water samples to achieve a concentration sufficient for downstream molecular experiments. To date, collected water samples have been filtered by humans or electric power using various instruments. We developed a simple gravity filtration system that does not need for an external force. The system comprises a plastic bag filled with a water sample (1 L), a filter cartridge, and a long plastic tube (e.g., 2 m). When hung at a height equal to the tube length, this filtration unit can enable power-free collection and concentration of eDNA at any remote location within a reasonable time (10-60 min).•A simple, rapid, power-free, practical filtration system for environmental DNA analysis is reported.•If there is a place to hang the filtration system, filtration can be performed anywhere.•The filtration speed increased when the system was hung higher.

Changes in postural sway during upright stance after short-term lower limb physical inactivity: A prospective study.

Previous studies have reported that motor behavior is affected by short-term physical inactivity using cast immobilization; however, the effects of inactivity on postural sway are not well-understood. This study aimed to investigate the effects of short-term lower limb disuse on postural sway in the upright position after cast removal. Twenty-two healthy young adults were enrolled, and each participant's lower limb on one side was fixed with a soft bandage and medical splint made from metal and soft urethane for 10 h. Fluctuations in the center of pressure (COP) were measured before and after immobilization; the total trajectory length, mean velocity, COP root mean square (RMS) area, mean medial-lateral (M-L) COP, and mean anterior-posterior (A-P) COP were selected as evaluation parameters. Compared with the postural sway before cast application, we noted an increase and shift (from the fixed to the nonfixed side) in the postural sway after cast removal. Our results therefore suggest that short-term disuse may cause acute changes in COP movements during quiet standing. Moreover, patients may maintain their standing posture by adopting a compensatory strategy involving lateral control, similar to individuals with stroke and patients who have undergone total knee arthroplasty.

Unilateral cathodal transcranial direct current stimulation over the parietal area modulates postural control depending with eyes open and closed.

OBJECTIVE: Cathodal transcranial direct current stimulation (C-tDCS) is generally assumed to inhibit cortical excitability. The parietal cortex contributes to multisensory information processing in the postural control system, and this processing is proposed to be different between the right and left hemispheres and sensory modality. However, previous studies did not clarify whether the effects of unilateral C-tDCS of the parietal cortex on the postural control system differ depending on the hemisphere. We investigated the changes in static postural stability after unilateral C-tDCS of the parietal cortex. METHODS: Ten healthy right-handed participants were recruited for right- and left-hemisphere tDCS and sham stimulation, respectively. The cathodal electrode was placed on either the right or left parietal area, whereas the anodal electrode was placed over the contralateral orbit. tDCS was applied at 1.5 mA for 15 min. We evaluated static standing balance by measuring the sway path length (SPL), mediolateral sway path length (ML-SPL), anteroposterior sway path length (AP-SPL), sway area, and the SPL per unit area (L/A) after 15-minute C-tDCS under eyes open (EO) and closed (EC) conditions. To evaluate the effects of C-tDCS on pre- and post-offline trials, each parameter was compared using two-way repeated-measures analysis of variance (ANOVA) with factors of intervention and time. A post-hoc evaluation was performed using a paired t-test. The effect sizes were evaluated according to standardized size-effect indices of partial eta-squared (ηp2) and Cohen's d. The power analysis was calculated (1-ß). RESULTS: A significant interaction was observed between intervention and time for SPL (F (2, 27) = 4.740, p = 0.017, ηp2 = 0.260), ML-SPL (F (2, 27) = 4.926, p = 0.015, ηp2 = 0.267), and sway area (F (2, 27) = 9.624, p = 0.001, ηp2 = 0.416) in the EO condition. C-tDCS over the right hemisphere significantly increased the SPL (p < 0.01, d = 0.51), ML-SPL (p < 0.01, d = 0.52), and sway area (p < 0.05, d = 0.83) in the EO condition. In contrast, C-tDCS over the left hemisphere significantly increased the L/A in both the EC and EO condition (EO; p < 0.05, d = 0.67, EC; p < 0.05, d = 0.57). CONCLUSION: These results suggest that the right parietal region contributes to static standing balance through chiefly visual information processing during the EO condition. On the other hand, L/A increase during EC and EO by tDCS over the left parietal region depends more on somatosensory information to maintain static standing balance during the EC condition.