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We hypothesized that social jetlag would be associated with prolonged sleep duration on weekends and irregularities in wake-up time and/or bedtime on weekdays. In total, 1,200 Japanese male college students were included in this study. Participants completed an eight-day sleep diary in which they recorded their wake-up time, bedtime, and sleep duration every day for a week. Mean wake-up time, bedtime, and sleep duration, standard deviations in wake-up time and bedtime, the coefficient of variation in sleep duration, social jetlag, and chronotype were calculated over seven nights. Multiple regression was used to explore the factors influencing social jetlag. Stepwise selection analysis was performed to analyze the parameters identified on multiple regression analysis. The mean chronotype of the included participants was 5.3 ± 1.5; their mean social jetlag value was 1.1 ± 1.0. The mean wake-up time, bedtime, and sleep duration values were 8.5 ± 1.1, 25.0 ± 1.1, and 7.5 ± 1.1 h, respectively. Multiple regression analysis showed five indicators exerting a statistically significant influence on social jetlag. The standard deviation in wake-up time was adopted as the first factor in the stepwise selection analysis. These results show that social jetlag is associated with not only prolonged sleep duration on weekends but also irregularities in wake-up time during the week.

Background: In recent years, objective quantitative evaluations have become particularly important. Both qualitative and quantitative evaluations are also available for edema. It is thought that the technical problem of quantitative evaluation can be solved by using a simple and reproducible method. Several studies have evaluated various methods for measuring edema. Limitations, such as weaknesses, measurement complexity, and errors, have been identified. Therefore, this study aimed to consider a simple and effective measurement method for the quantitative evaluation of edema. Methods: This study was a prospective, observational study. The subjects were 15 healthy adults (2 male and 13 female). Measurements were performed on the subjects’ right lower leg once in the morning and once in the afternoon, with a minimum interval of 4 hours. Results: The actual volume of the lower leg was correlated with all indices except the ultrasonic echo findings for subcutaneous tissue. The intra-subject and inter-subject reliabilities for the indices using digital images were very high. The lower leg volume was greater significantly in the afternoon from the morning. Conclusion: The leg circumference was measured by utilizing a tape, while the width and volume were measured by utilizing digital imaging suitable for quantitatively evaluating edema. Furthermore, swelling of the lower leg with time can occur in the absence of daily exercise.

In this work we tackle the path planning problem for a 21-dimensional snake robot-like manipulator, navigating a cluttered gas turbine for the purposes of inspection. Heuristic search based approaches are effective planning strategies for common manipulation domains. However, their performance on high dimensional systems is heavily reliant on the effectiveness of the action space and the heuristics chosen. The complex nature of our system, reachability constraints, and highly cluttered turbine environment renders naive choices of action spaces and heuristics ineffective. To this extent we have developed i) a methodology for dynamically generating actions based on online optimization that help the robot navigate narrow spaces, ii) a technique for lazily generating these computationally expensive optimization actions to effectively utilize resources, and iii) heuristics that reason about the homotopy classes induced by the blades of the turbine in the robot workspace and a Multi-Heuristic framework which guides the search along the relevant classes. The impact of our contributions is presented through an experimental study in simulation, where the 21 DOF manipulator navigates towards regions of inspection within a turbine., Accepted for presentation at 2021 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)

Clear cell meningioma is a rare histological variant of meningioma, which often recurs aggressively. This video demonstrates a patient with a petroclival clear cell meningioma, which was resected completely through the anterior transpetrosal approach. The absence of intratumoral spotty signal voids on preoperative susceptibility-weighted imaging (SWI) suggested that the tumor was a meningioma rather than a schwannoma, although typical imaging features of meningioma were not observed. After surgery, the patient’s preoperative hearing disturbance improved from class D to class A, which the authors had sometimes experienced in cerebellopontine angle meningioma surgeries. Careful observation over a 2.5-year period revealed no tumor recurrence, without additional treatment. The video can be found here: https://stream.cadmore.media/r10.3171/2022.1.FOCVID21219

Background During voluntary muscle contraction, sensory information induced by electrostimulation of the nerves supplying the contracting muscle is inhibited and the somatosensory evoked potentials (SEPs) amplitude decreases. This depression of sensory input during voluntary muscle contraction has been demonstrated by many studies using electrophysiological methods. However, the association between the electrophysiological response of the sensory system during sustained muscle contraction and subjective peripheral sensation (SPS) is still unclear. The aim of this study was to investigate changes in spinal excitability, SEPs, and SPS during voluntary muscle contraction. Results The appearance rate of the F-wave was significantly higher during muscle contraction than rest, whereas no significant difference was observed in F-wave latency between muscle contraction and rest. Furthermore, the P25 amplitude of SEPs was significantly lower during muscle contraction than rest, whereas the N20 amplitude of SEPs exhibited no significant differences. The SPS was significantly lower during muscle contraction than rest Conclusions We conclude that sensory gating, which is found in the P25 component of SEPs during muscle contraction, is one of the neurophysiological mechanisms underlying the suppression of SPS.

Tirabrutinib (TIR), a Burton’s tyrosine kinase inhibitory drug, has been approved in Japan for treating relapsed/refractory primary central nervous system lymphoma (PCNSL). The authors recently encountered three patients with newly diagnosed refractory PCNSL using TIR. Three patients, 48, 78 and 88 years-old males, diagnosed with PCNSL by histologically verification were firstly treated with high dose Methotrexate based chemotherapy (HD-MTX) and/or radiotherapy, however these cases were refractory for these standard treatments, demonstrated early cerebrospinal fluid dissemination or accompanied with severe adverse event. The authors decided to administrate TIR to these patients with a full informed consent. TIR demonstrated dramatic reduction of the volume of tumor on MRI within one month after administration of TIR, and improved the patient’s performance status. However, one case demonstrated liver dysfunction and multiple brain abscess due to aspergillus infection, and one case demonstrated early progression of the tumor 49 days after starting TIR. Administration of TIR for the patients with newly diagnosed refractory PCNSL demonstrated a rapid and dramatic clinical response, and presented with several clinical implications for this complicated condition.

In the present study, a tandem-bicycle ergometer was developed, because it is believed that such an ergometer can be used to eliminate differences in signaling between single- and tandem-exercise in cardiorespiratory responses, and is able to quantify interdependence in one load. It is necessary to verify whether cardiorespiratory responses to submaximal exercise are the same between single and tandem-bicycle ergometers. Accordingly, we compared cardiorespiratory variables during exercise in three conditions: 1) with a general bicycle single saddle using a general bicycle ergometer, 2) with a tandem bicycle front saddle using a tandem ergometer, and 3) with a tandem bicycle rear saddle using a tandem ergometer. Eleven healthy males participated in this study. The subjects exercised for 15 min at three intensities (1.5, 2.0 and 2.5 kp) in each condition. The pedaling rate was constantly kept at 60 rpm. Heart rate (HR), oxygen uptake (VO2), and the rating of perceived exertion (RPE) were measured during the last minute of each intensity. There were no significant differences in the variables HR, VO2, and RPE at each load among the three conditions. The ranges of coefficient of variation (CV) values were 3.0 - 4.8%: HR and 4.2 - 5.1%: VO2. It was reported that between-day CV for HR and VO2 during treadmill running was 1.0 - 10.7% and 1.9 - 11.6%. Given these CV values of present and previous studies, it can be seen that physiological response is stable during developed tandem-bicycle ergometer exercise. These results suggest that cardiorespiratory responses to exercise are at comparable levels between a normal bicycle ergometer and the newly developed tandem-bicycle ergometer.

Water exercise is particularly important for lifestyle disease prevention and long-term care prevention, and is prevalent among the middle-aged and elderly population. During water immersion, buoyancy acts on the immersed body and the influence of gravity is reduced. In addition, cardiovascular responses, caused by blood shifts from the abdomen and legs to the thoracic region, occur due to water pressure, unlike in the case of land exercise. Resting water immersion at thermoneutral conditions (about 34°C water temperature) induces an increase in stroke volume, a reduction in heart rate, an increase in cardiac output, and a reduction of total peripheral vascular resistance, unlike resting on land. During water exercise and the recovery phase of water exercise, there are similar cardiovascular responses due to changes in blood flow. The water temperature and water level cause changes in these basic responses. It has been confirmed that water exercise does not lead to excessive responses in blood pressure, and is effective in cardiovascular rehabilitation. In addition, water immersion during the recovery phase after exercise has attracted attention as a rehabilitative exercise modality. Previous studies have suggested that the effects of immersion on cardiovascular response in the rest, exercise, and recovery phases provide benefits to the immersed person, but further studies are needed to confirm the effective application of the methods.

Objectives: There are several recommendations on the prevention of hypothermia during snow shoveling. However, there seemed to be insufficient evidence supporting these recommendations because they are not based on data from actual snow shoveling research. The purpose of this study was to investigate changes in brain temperature (tympanic temperature) and visceral temperature (rectal temperature) during snow shoveling among healthy young males. Methods: Eight healthy young males (age, 23.6 ± 2.4 years; weight, 69.7 ± 6.1 kg; height, 172.8 ± 7.3 cm) performed snow shoveling with an ordinary-size shovel for 15 min at their own pace in a rural snowfall area in December, 2009. Rectal temperature (Tre) and tympanic temperature (Tty) were measured 5 times (at rest, 5th (Ex5), 10th (Ex10), and 15th (Ex15) minute of snow shoveling; and 5th (Rec5) minute of recovery phase). The room temperature was 18.6 ± 0.7°C and the atmospheric temperature was 3.8 ± 2.6°C. Results: Tre continued to increase from at rest to Ex15. Tre at Ex15 (37.7 ± 0.3°C) was significantly higher (p < 0.05) than that at rest (37.2 ± 0.3°C). Tty at rest (36.7 ± 0.2°C) and Tty at Ex5 (36.6 ± 0.3°C) decreased significantly (p < 0.05) at Ex10 (36.2 ± 0.6°C). A significant negative correlation between changes in Tre and Tty were observed during snow shoveling (r = -0.49, p < 0.05). Conclusion: Discrepancy between changes in brain temperature (tympanic temperature) and visceral temperature (rectal temperature) should be taken into consideration in the prevention of disease development during snow shoveling in a cold environment.

The present study was performed to test the hypothesis that the blood pressure (BP) response to resistance exercise in middle-aged men with stiffening arteries is greater than that in young men with compliant arteries. The BP responses to acute dynamic resistance exercise (leg press) at individual relative (low, moderate and high) and absolute intensities were investigated in both young and middle-aged men. A total of 21 sedentary healthy normotensive men, 21-25 years of age (young) and 41-59 years of age (middle-aged), were included in the study. At rest, the arterial compliance (simultaneous ultrasound and applanation tonometry) and muscle strength (leg press) were lower, and indices of arterial stiffness and BP were higher in the middle-aged men than in the young men (p < 0.05). There were no significant differences in height, body mass, or heart rate between the two groups. During exercise, the systolic BP of the middle-aged men at 80% one-repetition maximum (1RM) was significantly lower than that of the young men for the last half of the exercise period (p < 0.05). The amounts of change in systolic and diastolic BP from baseline to the end of resistance exercise were lower in the middle-aged men than in the young men at individual relative intensities (p < 0.05) and at individual absolute intensity. In contrast to our hypothesis, these findings indicated that the BP response during dynamic resistance exercise using large muscle groups may be attenuated in middle-aged men relative to young men.

The purpose of this study was to determine the effects of water temperature on rectal temperature and oxygen uptake during supine floating. Eight healthy males volunteered for this study. This study was performed in a supine position at rest on land and in three water conditions (25, 30 and 35 degrees Celsius). All experiments were performed for 35 minutes. Water conditions of immersion at 25 degrees Celsius resulted in a decrease in rectal temperature and an increase in oxygen uptake. The changes in rectal temperature differed among individuals. A significant correlation was observed between changes in rectal temperature and % body fat. However, the changes in rectal temperature were affected by other factors. These data suggest that the changes in rectal temperature during immersion at 25 degrees Celsius could be affected by other factors elaborated in this paper.

The cross-sectional area (CSA) of large-conductance arteries increases in response to endurance training in humans. To determine whether training-induced changes in arterial structure are systemic in nature or, rather, are confined to the arteries supplying exercising muscles, we studied 10 young men who performed one-legged cycle training [80% of one-legged peak O2 uptake (V˙o 2 peak), 40 min/day, 4 days/wk] for 6 wk and detraining for another 6 wk. There were no significant differences in baseline one-leggedV˙o 2 peak and CSA of the common femoral artery and vein (via B-mode ultrasound) between experimental and control legs. In the experimental leg, one-leggedV˙o 2 peak increased 16% [from 3.0 ± 0.1 to 3.4 ± 0.1 (SE) l/min], arterial CSA increased 16% (from 84 ± 3 to 97 ± 5 mm2), and venous CSA increased 46% (from 56 ± 5 to 82 ± 5 mm2) after endurance training. These changes returned to baseline during detraining. There were no changes in one-leggedV˙o 2 peak and arterial CSA in the control leg, whereas femoral venous CSA in the control leg significantly increased 24% (from 54 ± 5 to 67 ± 4 mm2) during training. Changes in femoral arterial and venous CSA in the experimental leg were positively and significantly related to corresponding changes in one-leggedV˙o 2 peak ( r = 0.86 and 0.76, respectively), whereas there were no such relations in the control leg ( r = 0.10 and 0.17). When stepwise regression analysis was performed, a primary determinant of change inV˙o 2 peak was change in femoral arterial CSA, explaining ∼70% of the variability. These results support the hypothesis that the regional increase in blood flow, rather than systemic factors, is associated with the training-induced arterial expansion. Femoral arterial expansion may contribute, at least in part, to improvement in efficiency of blood transport from the heart to exercising muscles and may facilitate achievement of aerobic work capacity.

The effect of menstrual cycle phase on arterial elasticity is controversial. In 10 healthy women (20.6+/-1.5 years old, mean+/-s.d.), we investigated the variations in central and peripheral arterial elasticity, blood pressure (carotid and brachial), carotid intima-media thickness (IMT), and serum oestradiol and progesterone concentrations at five points in the menstrual cycle (menstrual, M; follicular, F; ovulatory, O; early luteal, EL; and late luteal, LL). Carotid arterial compliance (simultaneous ultrasound and applanation tonometry) varied cyclically, with significant increases from the values seen in M (0.164+/-0.036 mm2 mmHg-1) and F (0.171+/-0.029 mm2 mmHg-1) to that seen in the O phase (0.184+/-0.029 mm2 mmHg-1). Sharp declines were observed in the EL (0.150+/-0.033 mm2 mmHg-1) and LL phases (0.147+/-0.026 mm2 mmHg-1; F=8.51, P0.05). Pulse wave velocity in the leg (i.e. peripheral arterial stiffness) did not exhibit any significant changes. Fluctuations in carotid arterial elasticity correlated with the balance between oestradiol and progesterone concentrations. No significant changes were found in carotid and brachial blood pressures, carotid artery lumen diameter, or IMT throughout the menstrual cycle. These data provide evidence that the elastic properties of central, but not peripheral, arteries fluctuate significantly with the phases of the menstrual cycle.

To examine the possible age-related blood pressure (BP) deregulation in response to central hypervolemia, we measured spontaneous baroreflex sensitivity (SBRS), carotid arterial compliance (CC), and R-R interval coefficient of variation (RRICV) during basal and thermoneutral resting head-out-of-water immersion (HOWI) in 7 young (YG = 24.0 +/- 0.8 years) and 6 middle-aged/older (OL = 59.3 +/- 1.3 years) healthy men. Compared with basal conditions (YG = 19.6 +/- 4.0 vs OL = 6.1 +/- 1.5 ms/mmHg, P < 0.05), SBRS remained higher in YG than OL during rest HOWI (YG = 23.6 +/- 6.6 vs OL = 9.3 +/- 2.1 ms/mmHg, P < 0.05). The RRICV was significantly different between groups (YG = 6.5 +/- 1.4 vs OL = 2.8 +/- 0.4%, P < 0.05) under HOWI. The OL group had no increase in CC, but a significant increase in systolic BP (basal = 115.3 +/- 4.4 vs water = 129.3 +/- 5.3 mmHg, P < 0.05) under HOWI. In contrast, the YG group had a significant increase in CC (basal = 0.16 +/- 0.01 vs water = 0.17 +/- 0.02 mm(2)/mmHg, P < 0.05) with no changes in systolic BP. SBRS was positively related to CC (r = 0.58, P < 0.05 for basal vs r = 0.62, P < 0.05 for water). Our data suggest that age-related vagal dysfunction and reduced CC may be associated with SBRS differences between YG and OL groups, and with BP elevation during HOWI in healthy older men.