ESTIMATING A RUNNER\u27S STRIDE LENGTH AND FREQUENCY FROM A RACE VIDEO BY USING GROUND STITCHING

This study estimated stride length and frequency of runners in a 100 m race video. One method for measuring stride length and frequency is using infrared sensors. However, this method is not applicable to real races since numerous markers with infrared-reflective material must be attached to the runner’s entire body. Therefore, we proposed a method using a race video. We generated a panoramic image of the 100 m track to estimate the distance of each frame from the start line. We detected the positions of the runner’s steps from the movement of the leg joints. We projected every step to the overview image of the 100 m track. In the experiment, we applied our method to the video of an IAAF World Championship Track and Field 100 m race and obtained data from Usain Bolt. As a result, we can automatically estimate stride length and frequency of real races

Effects of trunk lean and foot lift exercises in sitting position on abdominal muscle activity and the contribution rate of transversus abdominis

Purpose: Abdominal hollowing exercise has been recommended to improve trunk stability. Trunk lean and foot lift exercises while sitting may easily promote abdominal muscle activity even in people who cannot perform abdominal hollowing consciously. The purpose of the present study was to examine the changes in abdominal muscle activity and contribution rate of the transversus abdominis muscle (TrA) when leaning the trunk and lifting the foot during sitting. Methods: The muscle stiffnesses (indicators of muscle activity) of the right rectus abdominis, external oblique, internal oblique, and TrA of 14 healthy men were measured during abdominal hollowing and the following nine sitting tasks: reference posture, 15° and maximal posterior trunk lean, 20° and maximal ipsilateral and contralateral trunk lean, and ipsilateral and contralateral foot lift. The TrA contribution rate was calculated by dividing the TrA stiffness by the sum of the abdominal muscles’ stiffnesses. Results: The TrA stiffness was significantly higher in abdominal hollowing than in reference posture, posterior and ipsilateral trunk lean, and ipsilateral foot lift, but not higher than in contralateral trunk lean and contralateral foot lift. There was no significant difference in the TrA contribution rates between abdominal hollowing and ipsilateral or contralateral foot lift. Conclusion: The contralateral trunk lean or contralateral foot lift could enhance TrA activity for people who cannot perform abdominal hollowing consciously. The contralateral foot lift could particularly be beneficial to obtain selective activity of TrA

Aurora and Airglow Observations with an All-Sky Imager on Shirase to Fill the Observation Gap over the Southern Ocean

The Tenth Symposium on Polar Science/Special session: [S] Future plan of Antarctic research: Towards phase X of the Japanese Antarctic Research Project (2022-2028) and beyond, Tue. 3 Dec. / Entrance Hall (1st floor) at National Institute of Polar Research (NIPR

Mechanisms of Photoisomerization and Water Oxidation Catalysis of Ruthenium(II) Aquo Complexes

Polypyridyl ruthenium(II) complexes have been widely researched as promising functional molecules. We have found unique photoisomerization reactions of polypyridyl ruthenium(II) aquo complexes. Recently we have attempted to provide insight into the mechanism of the photoisomerization of the complexes and distinguish between the distal−/proximal-isomers in their physicochemical properties and functions. Moreover, polypyridyl ruthenium(II) aquo complexes have been intensively studied as active water oxidation catalysts (WOCs) which are indispensable for artificial photosynthesis. The catalytic aspect and mechanism of water oxidation by the distal-/proximal-isomers of polypyridyl ruthenium(II) aquo complexes have been investigated to provide the guided thought to develop more efficient molecular catalysts for water oxidation. The recent progress on the photoisomerization and water oxidation of polypyridyl ruthenium(II) aquo complexes in our group are reviewed to understand the properties and functions of ruthenium complexes

Fabrication of a 64-Pixel TES Microcalorimeter Array with Iron Absorbers Uniquely Designed for 14.4-keV Solar Axion Search

If a hypothetical elementary particle called an axion exists, to solve the strong CP problem, a 57Fe nucleus in the solar core could emit a 14.4-keV monochromatic axion through the M1 transition. If such axions are once more transformed into photons by a 57Fe absorber, a transition edge sensor (TES) X-ray microcalorimeter should be able to detect them efficiently. We have designed and fabricated a dedicated 64-pixel TES array with iron absorbers for the solar axion search. In order to decrease the effect of iron magnetization on spectroscopic performance, the iron absorber is placed next to the TES while maintaining a certain distance. A gold thermal transfer strap connects them. We have accomplished the electroplating of gold straps with high thermal conductivity. The residual resistivity ratio (RRR) was over 23, more than eight times higher than a previous evaporated strap. In addition, we successfully electroplated pure-iron films of more than a few micrometers in thickness for absorbers and a fabricated 64-pixel TES calorimeter structure.Comment: 5 pages, 5 figures, published in IEEE Transactions on Applied Superconductivity on 8 March 202

Genetic population structure of the polkadot skate (Dipturus chinensis) around Japan, based on mitochondrial DNA sequences and polymorphic microsatellite loci

The genetic population structure of the polkadot skate (Dipturus chinensis) around Japan was examined by using mitochondrial (mt) cytochrome (cyt) b gene sequences and polymorphic microsatellite (simple sequence repeat [SSR]) loci. Results of phylogenetic analysis based on mt cyt b gene sequences reveal 2 major lineages, clades A and B. Clade A consists of populations in the Sea of Japan and the East China Sea. Clade B contains populations in the Pacific Ocean and is divided into 2 subclades, clades B1 and B2, which correspond to the populations along the southern and northern coasts of Japan, respectively. This genetic differentiation is also supported by results from SSR analysis. The divergence of clades A and B may reflect isolation of the East China Sea from the Pacific Ocean in the Early Pleistocene. After diverging from clade A, clade B might have extended its distribution northward along the Pacific coast of Japan and divided into clades B1 and B2 in the Middle Pleistocene. The polkadot skate is clearly structured into 3 genetically discrete populations around Japan that should be treated as independent management units for management of this species in the future

Left Atrial Functional Response after a Marathon

Background: Middle-aged marathon runners have an increased risk of developing atrial fibrillation (AF). A previous study described that repetitive marathon running was associated with left atrial (LA) dysfunction. However, whether this change is common in marathon runners and which runners are at risk of LA dysfunction remain unknown. The purpose of this study was to determine which factors could predict LA dysfunction. Methods and results: We prospectively examined 12 healthy amateur volunteers (9 males, 31±8 years old) who participated in a full marathon. All echocardiographic measurements and speckle-tracking echocardiography were performed before and after the marathon. The endpoint was defined as reduced LA reservoir strain one day after the marathon (non-responder group). Seven participants were in the non-responder group. Age (35±9 vs. 26±2 yrs., p=0.020), augmentation index (76±12 vs. 55±8, p=0.002), and diastolic blood pressures (83±11 vs. 70±7 mmHg, p=0.021) in the non-responder group were significantly higher compared with the responder group. In multivariate linear regression analysis, only the augmentation index was an independent predictor of reduced LA reservoir function after the marathon (β=-0.646, p=0.023). Conclusion: The augmentation index was a predictive marker for reduction in LA reservoir function after a marathon in healthy amateur volunteers

RV Function in Cardiac Rehabilitation

Cardiac rehabilitation had an important role in the management of heart failure. The predictors of exercise capacity improvement after cardiac rehabilitation are required in the management of heart failure. We demonstrated that patients with higher right ventricular strain during preload augmentation seem to have a benefit more from cardiac rehabilitation. The simple, but novel application of preload stress echocardiography is a noninvasive technique that can be used to find a beneficial group with cardiac rehabilitation.Background: It has been recognized that a comprehensive cardiac rehabilitation (CR) program improves mortality in patients with chronic heart failure (HF). On the other hand, the magnitude of the improvement in exercise capacity after CR differs among individuals. The aim of this study was to assess the echocardiographic determinants of responders to CR using preload stress echocardiography. Methods: We prospectively enrolled 58 chronic HF patients with reduced left ventricular ejection fraction (LVEF) (age 62±11 years; 69% male; LVEF 43±7 %) who had received optimized medical treatment in a CR program for 5 months. We performed preload echocardiographic studies using leg positive pressure (LPP) to assess the echocardiographic parameters during preload augmentation. We defined 41 patients as a development cohort to assess the predictive value of echocardiographic variables. Next, we validated results in the remaining 17 patients as a validation cohort. Results: In the development cohort, significant improvement in peak VO2 (>10%) after CR was observed in 58% patients. In a multivariable logistic regression model, the significant predictor of improvement in exercise capacity was right ventricular (RV) strain during LPP (odds ratio: 3.96 per 1 SD; p =0.01). A RV strain value of –16% during LPP had good sensitivity of 0.79 and specificity of 0.71 to identify patients with improvement in peak VO2. In the validation cohort, an optimal cut off value of RV strain value was the same (AUC: 0.77, sensitivity: 0.78, specificity: 0.65). Conclusion: RV strain during LPP may be an echocardiographic parameter for assessing beneficial effects of CR