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Abstract Background Despite the well-known health benefits of exercise, women’s participation in exercise is low worldwide. As women are at risk of developing various chronic diseases as they age, suggesting effective exercise methods that can maximize energy consumption is needed to prevent such conditions. Excess post-exercise oxygen consumption (EPOC) can maximize energy consumption. In this crossover, randomized controlled trial, we aimed to compare the EPOC for different exercise modalities including continuous exercise (CE), interval exercise (IE), and accumulated exercise (AE) that spent the homogenized energy expenditure during exercise in healthy women. Methods Forty-four participants (age, 36.09 ± 11.73 years) were recruited and randomly allocated to three groups. The intensity of each modality was set as follows: CE was performed for 30 min at 60% peak oxygen uptake (VO2peak). IE was performed once for 2 min at 80% VO2peak, followed by 3 min at 80% VO2peak, and 1 min at 40% VO2peak, for a total of six times over 26 min. AE was performed for 10 min with a 60% VO2peak and was measured thrice a day. Results During exercise, energy metabolism was higher for IE and CE than that for AE. However, this was reversed for AE during EPOC. Consequently, the greatest energy metabolism was shown for AE during total time (exercise and EPOC). Conclusions By encouraging regular exercises, AE can help maintain and improve body composition by increasing compliance with exercise participation, given its short exercise times, and by efficiently increasing energy consumption through the accumulation of EPOC. Trial registration Clinical number (KCT0007298), 18/05/2022, Institutional Review Board of Konkuk University (7001355-202201-E-160).

Fractography of stress corrosion cracking (SCC) of 20% cold worked Type 304 H stainless steel containing δ-ferrite was studied using a compact tension (CT) specimen in oxidizing primary water with a scanning electron microscope (SEM) and electron back scattered diffraction (EBSD). The stress corrosion crack propagated mostly in transgranular stress corrosion cracking (TGSCC) mode and sometimes in intergranular stress corrosion cracking (IGSCC) mode. TGSCC paths were along the {111} plane with both high resolved shear stress and high resolved tensile stress. IGSCC preferentially propagated along the grain boundary perpendicular to the loading axis. The findings in this work suggest that TGSCC proceeds through formation of a weakening zone at the head of the crack tip by interaction of slip and corrosion and then cracking of the weakened zone by tensile stress.

Measuring the residual stress in the components in nuclear power plants is crucial to their safety evaluation. The instrumented indentation technique is a minimally invasive approach that can be conveniently used to determine the residual stress in structural materials in service. Because the indentation behavior of a structure with residual stresses is closely related to the elastic-plastic behavior of the indented material, an accurate understanding of the elastic-plastic behavior of the material is essential for evaluation of the residual stresses in the structures. However, due to the analytical problems associated with solving the elastic-plastic behavior, empirical equations with limited applicability have been used. In the present study, the impact of the non-equibiaxial residual stress state on indentation behavior was investigated using finite element analysis. In addition, a new nonequibiaxial residual-stress prediction methodology is proposed using a convolutional neural network, and the performance was validated. A more accurate residual-stress measurement will be possible by applying the proposed residual-stress prediction methodology in the future.

The purpose of our study to determine the effects of interval hypoxic training (IHT) and repeated sprint training in hypoxia (RSH) on metabolic and cardiac function during submaximal exercise, aerobic and anaerobic performance, and time trial performance in elite Korean national male mountain bike (MTB) cyclists. The participants included elite Korean national male MTB cyclists (n = 4) preparing for the 19th Asian Games in Hangzhou 2022. The hypoxic training frequency was 90 min (3 days per week for 4 weeks). Before and after hypoxic training, metabolic and cardiac functions during submaximal exercise, aerobic performance, anaerobic performance and time trial performance were measured. Oxygen uptake, carbon dioxide excretion, and heart rate tended to decrease, and stroke volume, end-diastolic volume and cardiac output tended to increase. In aerobic, anaerobic and time trial performances, the peak torque in aerobic performance significantly increased (p = 0.046). Maximal oxygen uptake and exercise time in aerobic performance, relative peak power, relative mean power, post-exercise blood lactate level, fatigue index in anaerobic performance, and time trial performance showed an improved tendency (all p = 0.068). Our pilot study confirmed that although the sample size was small, IHT and RSH can potentially improve athletic performance in elite Korean national male MTB cyclists.

Alzheimer's disease (AD) is heterogeneous, but existing methods for capturing this heterogeneity through dimensionality reduction and unsupervised clustering have limitations when it comes to extracting intricate atrophy patterns. In this study, we propose a deep learning based self-supervised framework that characterizes complex atrophy features using latent space representation. It integrates feature engineering, classification, and clustering to synergistically disentangle heterogeneity in Alzheimer's disease. Through this representation learning, we trained a clustered latent space with distinct atrophy patterns and clinical characteristics in AD, and replicated the findings in prodromal Alzheimer's disease. Moreover, we discovered that these clusters are not solely attributed to subtypes but also reflect disease progression in the latent space, representing the core dimensions of heterogeneity, namely progression and subtypes. Furthermore, longitudinal latent space analysis revealed two distinct disease progression pathways: medial temporal and parietotemporal pathways. The proposed approach enables effective latent representations that can be integrated with individual-level cognitive profiles, thereby facilitating a comprehensive understanding of AD heterogeneity.

To simulate the verification process using materials from a decommissioned reactor, a mock-up of the bottom-mounted instrument nozzle in the Kori 1 reactor, where the nozzle was attached to a plate by J-groove dissimilar metal welding, was fabricated. The mock-up distortion was quantified by measuring the plate surface displacement after welding. The residual stresses formed on the support plate surface and the inner surface of the nozzle were then analyzed using the hole-drilling method, contour method, and neutron diffraction. Welding simulations were performed using a 3D finite element method to validate the measured results. The measured and computed stress distributions on the support plate exhibited reasonable agreement. Conversely, the stresses on the inside of the nozzle were found to have an indisputable difference in the contour method and neutron diffraction measurements, which demonstrated strong tensile and compressive hoop stresses, respectively. The possible origins of such differences were investigated and we have provided some suggestions for a precise evaluation in the simulation. This study is expected to be useful in future research on decommissioned reactors.

Few studies have compared the differences between protein (whey protein hydrolysate (WPH) or whey protein concentrate (WPC)) intake conditions (at rest or post-resistance exercise). Therefore, the purpose of this study was to investigate the plasma amino acid levels after intake of WPH compared with WPC intake in young men at rest and post-resistance exercise. We also aimed to compare the differences in plasma amino acid levels after WPH intake with or without resistance exercise. Fifteen young men were recruited for this crossover study, where each participant took three supplements (placebo, WPH and WPC) once each at rest and post-resistance exercise over 9 weeks. Blood samples were collected at nine (0, 15, 30, 45, 60, 90, 120, 180, 240 min) and ten (pre, 0, 15, 30, 45, 60, 90, 120, 180, 240 min) time points, at rest and post-resistance exercise, respectively. Plasma amino acids (total amino acids, essential amino acids, branched amino acids and leucine) were measured. WPH intake resulted in faster bioavailability (approximately 15 min) and higher plasma amino acid concentrations in all plasma amino acids, regardless of the condition. In addition, WPH bioavailability tended to have similar peaks concentrations at rest and post-resistance exercise, whereas post-resistance exercise of WPC decreased sharply after 30 min and maintained a lower concentration than normal after 60 min. In conclusion, the results that WPH intake initially increased the concentration of plasma amino acids than WPC suggests that WPH is absorbed into the blood faster and may be more effective in increasing the rate of muscle protein synthesis. Moreover, although the intake of WPH after resistance exercise does not upregulate the peak concentrations of plasma amino acids, the synthesis of skeletal muscle can be increased through a rapid supply to tissues that require amino acids.

Background/Objectives: The present study examined the effect of 12-week combined exercise training in normobaric hypoxia on arterial stiffness, inflammatory biomarkers, and red blood cell (RBC) hemorheological function in 24 obese older women (mean age: 67.96 ± 0.96 years). Methods: Subjects were randomly divided into two groups (normoxia (NMX; n = 12) and hypoxia (HPX; n = 12)). Both groups performed aerobic and resistance exercise training programs three times per week for 12 weeks, and the HPX group performed exercise programs in hypoxic environment chambers during the intervention period. Body composition was estimated using bioelectrical impedance analysis equipment. Arterial stiffness was measured using an automatic waveform analyzer. Biomarkers of inflammation and oxygen transport (tumor necrosis factor alpha, interleukin 6 (IL-6), erythropoietin (EPO), and vascular endothelial growth factor (VEGF)), and RBC hemorheological parameters (RBC deformability and aggregation) were analyzed. Results: All variables showed significantly more beneficial changes in the HPX group than in the NMX group during the intervention. The combined exercise training in normobaric hypoxia significantly reduced blood pressure (systolic blood pressure: p < 0.001, diastolic blood pressure: p < 0.001, mean arterial pressure: p < 0.001, pulse pressure: p < 0.05) and brachial–ankle pulse wave velocity (p < 0.001). IL-6 was significantly lower in the HPX group than in the NMX group post-test (p < 0.001). Also, EPO (p < 0.01) and VEGF (p < 0.01) were significantly higher in the HPX group than in the NMX group post-test. Both groups showed significantly improved RBC deformability (RBC EI_3Pa) (p < 0.001) and aggregation (RBC AI_3Pa) (p < 0.001). Conclusions: The present study suggests that combined exercise training in normobaric hypoxia can improve inflammatory biomarkers and RBC hemorheological parameters in obese older women and may help prevent cardiovascular diseases.

Recent studies suggest that lactate intake has a positive effect on glycogen recovery after exercise. However, it is important to verify the effect of lactate supplementation alone and the timing of glycogen recovery. Therefore, in this study, we aimed to examine the effect of lactate supplementation immediately after exercise on glycogen recovery in mice liver and skeletal muscle at 1, 3, and 5 h after exercise. Mice were randomly divided into the sedentary, exercise-only, lactate, and saline-treated groups. mRNA expression and activation of glycogen synthesis and lactate transport-related factors in the liver and skeletal muscle were assessed using real-time polymerase chain reaction. Skeletal muscle glycogen concentration showed an increasing trend in the lactate group compared with that in the control group at 3 and 5 h after post-supplementation. Additionally, exogenous lactate supplementation significantly increased the expression of core glycogen synthesis enzymes, lactate transporters, and pyruvate dehydrogenase E1 alpha 1 in the skeletal muscles. Conversely, glycogen synthesis, lactate transport, and glycogen oxidation to acetyl-CoA were not significantly affected in the liver by exogenous lactate supplementation. Overall, these results suggest that post-exercise lactate supplement enables glycogen synthesis and recovery in skeletal muscles.

Nitrate-rich beetroot juice (NRBRJ) can potentially enhance exercise performance and improve cardiovascular function, leading to an increased use of NRBRJ over the years. However, the combined effects of NRBRJ supplementation and exercise on cardiovascular function remain unclear. Therefore, this study compared cardiovascular function responses to submaximal exercise with either placebo (PLA) or NRBRJ supplementation in healthy men. Twelve healthy men (aged 25.2 ± 2.3 years) completed the 30-min submaximal cycle ergometer exercise trials corresponding to 70% maximal heart rate (HRmax) with either PLA or NRBRJ supplementation in a random order. The mean exercise load, heart rate (HR), stroke volume (SV), cardiac output (CO), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and total peripheral resistance (TPR) were measured during exercise. The brachial–ankle pulse wave velocity (baPWV) and flow-mediated dilation (FMD) were measured before and after exercise. NRBRJ supplementation was more effective than PLA in increasing the mean exercise load and decreasing DBP and MAP during submaximal exercise. Furthermore, baPWV decreased in the NRBRJ trial and was considerably lower after exercise in the NRBRJ-supplemented group than in the PLA-supplemented group. FMD significantly increased in the PLA and NRBRJ trials; however, NRBRJ supplementation demonstrated a significantly higher FMD before and after exercise than PLA supplementation. In conclusion, acute NRBRJ supplementation and exercise were more effective than PLA supplementation and exercise in improving aerobic exercise capacity and cardiovascular function in healthy men.

Background: This study investigates the effects of a 12-week circuit exercise program on blood pressure, vascular function, and inflammatory cytokines in older obese women with sarcopenia. Methods: Twenty-eight older obese women with sarcopenia (mean age: 78.2 ± 3.7 years) were randomly divided into an exercise group (EG, n = 14) and a control group (CG, n = 14). The EG participated in a 12-week circuit exercise training regimen, conducted three times weekly, with each session lasting between 45 to 75 minutes (progressively increased over time). The CG was advised to maintain their regular daily routines throughout the intervention period. All dependent variables, including blood pressure, vascular function, and inflammation cytokines, were evaluated pre- and post-intervention. Results: Positive changes were observed in the EG in body composition (body fat mass; p < 0.001, body fat percentage; p < 0.01, free-fat mass; p < 0.01), blood pressure (heart rate; p < 0.05, rate pressure product; p < 0.01), vascular function (brachial–ankle pulse wave velocity; p < 0.05, flow-mediated dilation; p < 0.001), and inflammation cytokines (interleukin-6; p < 0.05). In the CG, there was an increase in body fat mass (p < 0.05) and body fat percentage (p < 0.05), while no changes were observed in other variables. Conclusions: The 12-week circuit exercise program significantly reduced blood pressure, improved vascular function, and decreased inflammatory cytokines in obese older women with sarcopenia. However, individual variations in response highlight the need for personalized exercise regimens.

We compared the effects of chronic exogenous lactate and exercise training, which influence energy substrate utilization and body composition improvements at rest and during exercise, and investigated the availability of lactate as a metabolic regulator. The mice were divided into four groups: CON (sedentary + saline), LAC (sedentary + lactate), EXE (exercise + saline), and EXLA (exercise + lactate). The total experimental period was set at 4 weeks, the training intensity was set at 60–70% VO2max, and each exercise group was administered a solution immediately after exercise. Changes in the energy substrate utilization at rest and during exercise, the protein levels related to energy substrate utilization in skeletal muscles, and the body composition were measured. Lactate intake and exercise increased carbohydrate oxidation as a substrate during exercise, leading to an increased energy expenditure and increased protein levels of citrate synthase and malate dehydrogenase 2, key factors in the TCA(tricarboxylic acid) cycle of skeletal muscle. Exercise, but not lactate intake, induced the upregulation of the skeletal muscle glucose transport factor 4 and a reduction in body fat. Hence, chronic lactate administration, as a metabolic regulator, influenced energy substrate utilization by the skeletal muscle and increased energy expenditure during exercise through the activation of carbohydrate metabolism-related factors. Therefore, exogenous lactate holds potential as a metabolic regulator.

The implantation of good-quality embryos to the receptive endometrium is essential for successful live birth through in vitro fertilization (IVF). The higher the quality of embryos, the higher the live birth rate per cycle, and so efforts have been made to obtain as many high-quality embryos as possible after fertilization. In addition to an effective controlled ovarian stimulation process to obtain high-quality embryos, the composition of the embryo culture medium in direct contact with embryos in vitro is also important. During embryonic development, under the control of female sex hormones, the fallopian tubes and endometrium create a microenvironment that supplies the nutrients and substances necessary for embryos at each stage. During this process, the development of the embryo is finely regulated by signaling molecules, such as growth factors and cytokines secreted from the epithelial cells of the fallopian tube and uterine endometrium. The development of embryo culture media has continued since the first successful human birth through IVF in 1978. However, there are still limitations to mimicking a microenvironment similar to the reproductive organs of women suitable for embryo development in vitro. Efforts have been made to overcome the harsh in vitro culture environment and obtain high-quality embryos by adding various supplements, such as antioxidants and growth factors, to the embryo culture medium. Recently, there has been an increase in the number of studies on the effect of supplementation in different clinical situations such as old age, recurrent implantation failure (RIF), and unexplained infertility; in addition, anticipation of the potential benefits from individuation is rising. This article reviews the effects of representative supplements in culture media on embryo development.

Heart rate variability (HRV) is an effective tool for objectively evaluating physiological stress indices in psychological states. This study aimed to develop multiple linear regression equations to predict HRV variables using physical characteristics, body composition, and heart rate (HR) variables (eg, sex, age, height, weight, body mass index, fat-free mass, percent body fat, resting HR, maximal HR, and HR reserve) in Korean adults. Six hundred eighty adults (male, n = 236, female, n = 444) participated in this study. HRV variable estimation multiple linear regression equations were developed using a stepwise technique. The regression equation’s coefficient of determination for time-domain variables was significantly high (SDNN = adjusted R 2 : 73.6%, P

Pigs are susceptible to cold stress due to the absence of brown fat caused by the partial deletion of uncoupling protein 1 during their evolution. Some local pig breeds in China exhibit potential cold adaptability, but research has primarily focused on fat and intestinal tissues. Skeletal muscle plays a key role in adaptive thermogenesis in mammals, yet the molecular mechanism of cold adaptation in porcine skeletal muscle remains poorly understood. This study investigated the cold adaptability of two pig breeds, Mashen pigs (MS) and Large White pigs (LW), in a four-day cold (4 °C) or normal temperature (25 °C) environment. We recorded phenotypic changes and collected blood and longissimus dorsi muscle for transcriptome sequencing. Finally, the PRSS8 gene was randomly selected for functional exploration in porcine skeletal muscle satellite cells. A decrease in body temperature and body weight in both LW and MS pigs under cold stress, accompanied by increased shivering frequency and respiratory frequency, were observed. However, the MS pigs demonstrated stable physiological homeostasis, indicating a certain level of cold adaptability. The LW pigs primarily responded to cold stress by regulating their heat production and glycolipid energy metabolism. The MS pigs exhibited a distinct response to cold stress, involving the regulation of heat production, energy metabolism pathways, and robust mitochondrial activity, as well as a stronger immune response. Furthermore, the functional exploration of PRSS8 in porcine skeletal muscle satellite cells revealed that it affected cellular energy metabolism and thermogenesis by regulating ERK phosphorylation. These findings shed light on the diverse transcriptional responses of skeletal muscle in LW and MS pigs under cold stress, offering valuable insights into the molecular mechanisms underlying cold adaptation in pigs.

With the emergence of coronavirus disease 2019, individuals have been participating in online exercises to maintain their health while avoiding infection. Among these online exercises, Pilates intervention is a popular modality. This study aimed to examine the differences between online and face-to-face Pilates interventions in terms of various physiological parameters and included 30 middle-aged individuals (age 43.3 ± 5.5 years) with obesity. These individuals were randomly divided into a face-to-face Pilates group (FPG), an online Pilates group (OPG), and a control group (CG). The FPG and OPG performed a 60-min mat Pilates program with a Borg scale of 11–17, three times a week for 12 weeks. The participants in the CG maintained their daily routines. Body composition, mechanical muscle properties, cardiometabolic parameters, mental health, and physical fitness were assessed before and after 12 weeks of intervention. No significant differences in body composition or cardiometabolic parameters were observed between groups. However, the FPG and OPG showed greater improvements than the CG in terms of muscle mechanical properties, cardiometabolic parameters, mental health, and physical fitness. In addition, the FPG showed greater improvement than the OPG. In conclusion, face-to-face Pilates is a more effective modality than online Pilates, although both modalities improve health-related parameters.

Issues of fairness and consistency in Taekwondo poomsae evaluation have often occurred due to the lack of an objective evaluation method. This study proposes a three-dimensional (3D) convolutional neural network–based action recognition model for an objective evaluation of Taekwondo poomsae. The model exhibits robust recognition performance regardless of variations in the viewpoints by reducing the discrepancy between the training and test images. It uses 3D skeletons of poomsae unit actions collected using a full-body motion-capture suit to generate synthesized two-dimensional (2D) skeletons from desired viewpoints. The 2D skeletons obtained from diverse viewpoints form the training dataset, on which the model is trained to ensure consistent recognition performance regardless of the viewpoint. The performance of the model was evaluated against various test datasets, including projected 2D skeletons and RGB images captured from diverse viewpoints. Comparison of the performance of the proposed model with those of previously reported action recognition models demonstrated the superiority of the proposed model, underscoring its effectiveness in recognizing and classifying Taekwondo poomsae actions.

Abstract Background Immunotherapy has been administered to many patients with non-small-cell lung cancer (NSCLC). However, only few studies have examined toxicity in patients receiving an immune checkpoint inhibitor (ICI) after concurrent chemoradiotherapy (CCRT). Therefore, we performed a retrospective study to determine factors that predict radiation pneumonitis (RP) in these patients. Methods We evaluated the size of the planning target volume, mean lung dose (MLD), and the lung volume receiving more than a threshold radiation dose (VD) in 106 patients. The primary endpoint was RP ≥ grade 2, and toxicity was evaluated. Results After CCRT, 51/106 patients were treated with ICI. The median follow-up period was 11.5 months (range, 3.0–28.2), and RP ≥ grade 2 occurred in 47 (44.3%) patients: 27 and 20 in the ICI and non-ICI groups, respectively. Among the clinical factors, only the use of ICI was associated with RP (p = 0.043). Four dosimetric variables (MLD, V20, V30, and V40) had prognostic significance in univariate analysis for occurrence of pneumonitis (hazard ratio, p-value; MLD: 2.3, 0.009; V20: 2.9, 0.007; V30: 2.3, 0.004; V40: 2.5, 0.001). Only V20 was a significant risk factor in the non-ICI group, and MLD, V30, and V40 were significant risk factors in the ICI group. The survival and local control rates were superior in the ICI group than in the non-ICI group, but no significance was observed. Conclusions Patients receiving ICI after definitive CCRT were more likely to develop RP, which may be related to the lung volume receiving high-dose radiation. Therefore, several factors should be carefully considered for patients with NSCLC.

A FAC (flow-accelerated corrosion) test was performed for a straight pipe composed of the SA335 Gr P22 and SA106 Gr B (SA106-SA335-SA106) types of steel with welds as a function of the flow rate in the range of 7–12 m/s at 150 °C and with DO

BackgroundBrain connectivity is useful for deciphering complex brain dynamics controlling interregional communication. Identifying specific brain phenomena based on brain connectivity and quantifying their levels can help explain or diagnose neurodegenerative disorders.ObjectiveThis study aimed to establish a unified framework to identify brain connectivity-based biomarkers associated with disease progression and summarize them into a single numerical value, with consideration for connectivity-specific structural attributes.MethodsThis study established a framework that unifies the processes of identifying a brain connectivity-based biomarker and mapping its abnormality level into a single numerical value, called a biomarker abnormality summarized from the identified connectivity (BASIC) score. A connectivity-based biomarker was extracted in the form of a connected component associated with disease progression. BASIC scores were constructed to maximize Kendall's rank correlation with the disease, considering the spatial autocorrelation between adjacent edges. Using functional connectivity networks, we validated the BASIC scores in various scenarios.ResultsOur proposed framework was successfully applied to construct connectivity-based biomarker scores associated with disease progression, characterized by two, three, and five stages of Alzheimer's disease, and reflected the continuity of brain alterations as the diseases advanced. The BASIC scores were not only sensitive to disease progression, but also specific to the trajectory of a particular disease. Moreover, this framework can be utilized when disease stages are measured on continuous scales, resulting in a notable prediction performance when applied to the prediction of the disease.ConclusionOur unified framework provides a method to identify brain connectivity-based biomarkers and continuity-reflecting BASIC scores that are sensitive and specific to disease progression.

This study investigated the acute effects of natural antioxidants, derived from yeast fermentation containing glutathione and dietary vitamin C supplementation, on metabolic function, skeletal muscle oxygenation, cardiac function, and antioxidant function during submaximal exercise in middle-aged triathlon athletes. Twelve participants (aged 49.42 ± 5.9 years) completed 90 min submaximal cycling trials corresponding to 70% maximal oxygen uptake with either vitamin C and glutathione (VitC+Glu), vitamin C (VitC), glutathione (Glu) supplementation, or placebo. Metabolic function (minute ventilation, oxygen uptake, carbon dioxide output [VCO2], respiratory exchange ratio [RER], oxygen pulse [O2pulse], carbohydrate oxidation, fat oxidation, and energy expenditure), skeletal muscle oxygenation (oxidized hemoglobin and myoglobin in skeletal muscle tissue, total hemoglobin and myoglobin in skeletal muscle tissue [tHb]), cardiac function (heart rate [HR], stroke volume [SV], cardiac output, end-diastolic volume, end-systolic volume, and ejection fraction), and antioxidant function parameters (blood lactate, superoxide dismutase, catalase, glutathione peroxidases, glutathione [GSH], diacron reactive oxygen metabolite [dROM], and biological antioxidant potential [BAP]) were measured during submaximal exercise and recovery. VCO2, RER, HR, blood lactate after exercise, and dROM were significantly lower, and O2pulse, tHb, and BAP were significantly higher for VitC+Glu than for the other trials (p < 0.05). In conclusion, combined vitamin C and glutathione supplementation was more effective in improving metabolic function, skeletal oxygenation, cardiac function, and antioxidant function during prolonged submaximal exercise in middle-aged triathletes.

Background: This study investigated the effects of 12-week resistance training on body composition, blood pressure, blood lipid levels, muscle cross-sectional area (CSA), isokinetic muscle function, and hemorheological properties in middle-aged obese women. Methods: Twenty-eight obese women with a mean age of 50.79 ± 5.80 years were randomly assigned to the control (CON, n = 13) or experimental (EXP, n = 15) group. The EXP group underwent a resistance training program composed of warm-up, main resistance exercise (deadlift, barbell squat, seated leg extension, and lying leg curl, bench press, preacher bench biceps curl, barbell rowing, and dumbbell shoulder press), and cool-down. The resistance exercise consisted of three sets of 8–10 repetitions (reps) performed with 70–80% of 1-rep maximum, and reps and sets were increased every 3 weeks. The training frequency was 80 min, 3 days per week for 12 weeks. The CON group maintained their daily lifestyle without training. All participants underwent measurements of body composition (weight, body mass index, lean body mass, fat mass, and % body fat), blood pressure (systolic blood pressure, diastolic blood pressure, mean arterial pressure, and pulse pressure), blood lipid levels (triglycerides, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol), CSA of the muscles (quadriceps, hamstring, and total thigh muscle), isokinetic muscle function (peak torque [PT], relative PT, mean power, and total work [TW]), and hemorheological properties (erythrocyte deformability and aggregation) before and after 12 weeks of training. Results: The EXP group showed a significant improved muscle function, including PT (p < 0.001), relative PT (p < 0.001) in extension 60°/s, TW (p < 0.001) in extension 180°/s, and TW (p = 0.018) in flexion 180°/s. Regarding hemorheological properties, the EXP group showed significant improvement in erythrocyte aggregation (p < 0.001) and deformability (p < 0.001). Conclusions: The present study verified that our resistance training program resulted in greater muscle function, decreased fat mass, and improved hemorheological properties. Clinical Trial Registration: This study was registered with cris.nih.go.kr (No. KCT0007412).

Abstract We investigated the effect of education on the edge efficiency in resting state functional networks (RSFNs) in amnestic mild cognitive impairment (aMCI) and Alzheimer’s disease dementia (ADD). We collected the data of 57 early aMCI, 141 late aMCI, 173 mild ADD, and 39 moderate-to-severe ADD patients. We used years of education as a proxy for cognitive reserve. We measured edge efficiency for each edge in RSFNs, and performed simple slope analyses to discover their associations with education level among the four groups. In the late aMCI, a sub-network that had hub nodes in the right middle frontal gyrus and the right posterior cingulate gyrus, showed a positive association between RSFN edge efficiency and education (threshold = 2.5, p = 0.0478). There was no negative effect of education on the RSFN edge efficiency. In the early aMCI, mild ADD, and moderate-to-severe ADD, there were no sub-networks showing positive or negative correlation between education and RSFN edge efficiency. There was a positive effect of higher education on RSFN edge efficiency in the late aMCI, but not in the early aMCI or ADD. This indicates that in late aMCI, those who have higher education level have greater ability to resist collapsed functional network.

Background Based on recent evidence on the importance of the presence of diabetes mellitus (DM) and fibrosis-4 (FIB-4) index in coronavirus disease 2019 (COVID-19) mortality, we analyzed whether these factors could additively predict such mortality. Methods This multicenter observational study included 1,019 adult inpatients admitted to university hospitals in Daegu. The demographic and laboratory findings, mortality, prevalence of severe disease, and duration of quarantine were compared between patients with and without DM and/or a high FIB-4 index. The mortality risk and corresponding hazard ratio (HR) were analyzed using the Kaplan-Meier method and Cox proportional hazard models. Results The patients with DM (n=217) exhibited significantly higher FIB-4 index and mortality compared to those without DM. Although DM (HR, 2.66; 95% confidence interval [CI], 1.63 to 4.33) and a high FIB-4 index (HR, 4.20; 95% CI, 2.21 to 7.99) were separately identified as risk factors for COVID-19 mortality, the patients with both DM and high FIB-4 index had a significantly higher mortality (HR, 9.54; 95% CI, 4.11 to 22.15). Higher FIB-4 indices were associated with higher mortality regardless of DM. A high FIB-4 index with DM was more significantly associated with a severe clinical course with mortality (odds ratio, 11.24; 95% CI, 5.90 to 21.41) than a low FIB-4 index without DM, followed by a high FIB-4 index alone and DM alone. The duration of quarantine and hospital stay also tended to be longer in those with both DM and high FIB-4 index. Conclusion Both DM and high FIB-4 index are independent and additive risk factors for COVID-19 mortality.

The dislocation density in strain-hardened Alloy 690 was analyzed using scanning transmission electron microscopy (STEM) to study the relationship between the local plastic strain and susceptibility to primary water stress corrosion cracking (PWSCC) in nuclear power plants. The test material was cold-rolled at various thickness reduction ratios from 10% to 40% to simulate the strain-hardening condition of plant components. The dislocation densities were measured at grain boundaries (GB) and in grain interiors of strain-hardened specimens from STEM images. The dislocation density in the grain interior monotonically increased as the strain-hardening proceeded, while the dislocation density at the GB increased with strain-hardening up to 20% but slightly decreases upon further deformation to 40%. The decreased dislocation density at the GB was attributed to the formation of deformation twins. After the PWSCC growth test of strain-hardened Alloy 690, the fraction of intergranular (IG) fracture was obtained from fractography. In contrast to the change in the dislocation density with strain-hardening, the fraction of IG fracture increased remarkably when strain-hardened over 20%. From the results, it was suggested that the PWSCC growth behavior of strain-hardened Alloy 690 not only depends on the dislocation density, but also on the microstructural defects at the GB.

ObjectiveAnalyzing neuroimages being useful method in the field of neuroscience and neurology and solving the incompatibilities across protocols and vendors have become a major problem. We referred to this incompatibility as “center effects,” and in this study, we attempted to correct such center effects of cortical feature obtained from multicenter magnetic resonance images (MRIs).MethodsFor MRI of a total of 4,321 multicenter subjects, the harmonized w-score was calculated by correcting biological covariates such as age, sex, years of education, and intercranial volume (ICV) as fixed effects and center information as a random effect. Afterward, we performed classification tasks using principal component analysis (PCA) and linear discriminant analysis (LDA) to check whether the center effect was successfully corrected from the harmonized w-score.ResultsFirst, an experiment was conducted to predict the dataset origin of a random subject sampled from two different datasets, and it was confirmed that the prediction accuracy of linear mixed effect (LME) model-based w-score was significantly closer to the baseline than that of raw cortical thickness. As a second experiment, we classified the data of the normal and patient groups of each dataset, and LME model-based w-score, which is biological-feature-corrected values, showed higher classification accuracy than the raw cortical thickness data. Afterward, to verify the compatibility of the dataset used for LME model training and the dataset that is not, intraobject comparison and w-score RMSE calculation process were performed.ConclusionThrough comparison between the LME model-based w-score and existing methods and several classification tasks, we showed that the LME model-based w-score sufficiently corrects the center effects while preserving the disease effects from the dataset. We also showed that the preserved disease effects have a match with well-known disease atrophy patterns such as Alzheimer’s disease or Parkinson’s disease. Finally, through intrasubject comparison, we found that the difference between centers decreases in the LME model-based w-score compared with the raw cortical thickness and thus showed that our model well-harmonizes the data that are not used for the model training.

The global market for nutritional supplements (NS) is growing rapidly, and the use of L-arginine (Arg), L-citrulline (Cit), and citrulline malate (CitMal) supplements has been shown to enhance cardiovascular health and athletic performance. Over the past decade, Arg, Cit, and CitMal supplements have received considerable attention from researchers in the field of exercise nutrition, who have investigated their potential effects on hemodynamic function, endothelial function, aerobic and anaerobic capacity, strength, power, and endurance. Previous studies were reviewed to determine the potential impact of Arg, Cit, and CitMal supplements on cardiovascular health and exercise performance. By synthesizing the existing literature, the study aimed to provide insight into the possible uses and limitations of these supplements for these purposes. The results showed that both recreational and trained athletes did not see improved physical performance or increased nitric oxide (NO) synthesis with 0.075 g or 6 g doses of Arg supplement per body weight. However, 2.4 to 6 g of Cit per day for 7 to 16 days of various NSs had a positive impact, increasing NO synthesis, enhancing athletic performance indicators, and reducing feelings of exertion. The effects of an 8 g acute dose of CitMal supplement were inconsistent, and more research is needed to determine its impact on muscle endurance performance. Based on the positive effects reported in previous studies, further testing is warranted in various populations that may benefit from nutritional supplements, including aerobic and anaerobic athletes, resistance-trained individuals, elderly people, and clinical populations, to determine the impact of different doses, timing of ingestion, and long-term and acute effects of Arg, Cit, and CitMal supplements on cardiovascular health and athletic performance.

Purpose This study aimed to investigate the effects of acute cold stress (10℃, 0℃) compared with ordinary temperature (20℃) on exercise performance and physiological response at rest and during exercise. Methods A total of 10 healthy men (21.55 ± 2.16) were selected. In each environmental condition (20℃, 10℃, 0℃), the three testing order was randomly selected at crossover, and there was a week interval between the graded exercise test (GXT). On the testing day, they remained resting for 30 min in each environmental condition. Dependent variables (body temperature, energy metabolism parameters, skeletal muscle oxygenation profiles, and exercise performance parameters) were measured at rest and during GXT. Results In body temperature, at each environmental condition, there was a significant decrease (p

The main advantage of measuring functional fitness (FF) in older adults is that individual tests can estimate and track the rate of decline with age. This study aimed to develop a multiple linear regression model for predicting FF variables using easy-to-measure independent variables (e.g., sex, age, body mass index, and percent body fat) in Korean older adults. National Fitness Award datasets from the Republic of Korea were used in this analysis. The participants were aged ≥65 years and included 61,465 older men and 117,395 older women. The FF variables included the hand grip strength, lower body strength (30-s chair stand), lower body flexibility (chair sit-and-reach), coordination (figure of 8 walk), agility/dynamic balance (timed up-and-go), and aerobic endurance (2-min step test). An estimation multiple linear regression model was developed using a stepwise technique. In the regression model, the coefficient of determination in the hand grip strength test (adjusted R2 = 0.773, p < 0.001) was significantly high. However, the coefficient of determination in the 30-s chair stand (adjusted R2 = 0.296, p < 0.001), chair sit-and-reach (adjusted R2 = 0.435, p < 0.001), figure of 8 walk (adjusted R2 = 0.390, p < 0.001), timed up-and-go (adjusted R2 = 0.384, p < 0.001), and 2-min step tests (adjusted R2 = 0.196, p < 0.001) was significantly low to moderate. Our findings suggest that easy-to-measure independent variables can predict the hand grip strength in older adults. In future studies, explanatory power will be further improved if multiple linear regression analysis, including the physical activity level and nutritional status of older adults, is performed to predict the FF variables.

Interval training under hypoxia (IHT) is commonly used to enhance endurance exercise performance. However, previous studies examining hematologic changes related to the immune system that affect health and conditioning are lacking. This study aimed to evaluate the effects of IHT for 6-weeks on hematological parameters, hemodynamic function, and endurance exercise performance in amateur Korean female runners. Twenty healthy amateur Korean female runners (age: 24.85 ± 3.84 years) were equally assigned to normoxic training group (NTG) for interval training under normoxia (760 mmHg) and hypoxic training group (HTG) for interval training under hypobaric hypoxia (526 mmHg, 3000 m simulated altitude) according to their body composition and endurance exercise performance. All participants performed 120-min of training sessions, consisting of 20-min of warm-up, 60-min of interval training, and 20-min of cool-down. The training program was performed 3-days per week for 6-weeks. Warm-up and cool-down were performed for 20-min at 60% maximal heart rate (HRmax). The interval training sessions comprised 10 repetitions of interval exercise (5-min of exercise corresponding to 90–95% HRmax and 1-min of rest) on a treadmill. All participants underwent measurements of hematological parameters, hemodynamic function, and endurance exercise performance before and after training. Both groups showed a significant increase in erythropoietin (EPO) level and a decrease in monocyte abundance, with EPO showing a greater increase in the HTG than in the NTG. B cell abundance significantly increased in the NTG; hematocrit and neutrophil counts significantly increased, and lymphocyte counts significantly decreased in the HTG. The HTG showed a significant improvement in oxygen uptake, stroke volume index, and end-diastolic volume index compared to the NTG. In addition, both groups showed significant improvements in heart rate, end-systolic volume index, and cardiac output index. The maximal oxygen uptake and 3000 m time trial record were significantly improved in both groups, and the HTG showed a tendency to improve more than the NTG. In conclusion, the IHT was effective in enhancing endurance exercise performance through improved hemodynamic function. Furthermore, hematological parameters of immune system showed a normal range before and after training and were not negatively affected.

This study aimed to compare vascular function, cardiometabolic parameters, hemorheological function, and cardiorespiratory fitness in middle-aged Korean women according to obesity defined using body mass index (BMI). A total of 32 Korean women aged between 34 and 60 years (16 without obesity, mean age 46.31 ± 7.49 years and 16 with obesity, mean age 49.68 ± 6.69 years) participated in this study. Obesity was defined as BMI ≥ 25 kg/m2. The body composition, vascular function, cardiometabolic parameters, hemorheological function, and cardiorespiratory fitness of all participants were measured. Statistical differences in the dependent parameters between individuals with and without obesity were analyzed, and the correlations between BMI and the dependent variables were verified. The obese group showed significantly worse results (p

BackgroundCoronavirus disease 2019 (COVID-19) is a global pandemic that had affected more than eight million people worldwide by June 2020. Given the importance of the presence of diabetes mellitus (DM) for host immunity, we retrospectively evaluated the clinical characteristics and outcomes of moderate-to-severe COVID-19 in patients with diabetes.MethodsWe conducted a multi-center observational study of 1,082 adult inpatients (aged ≥18 years) who were admitted to one of five university hospitals in Daegu because of the severity of their COVID-19-related disease. The demographic, laboratory, and radiologic findings, and the mortality, prevalence of severe disease, and duration of quarantine were compared between patients with and without DM. In addition, 1:1 propensity score (PS)-matching was conducted with the DM group.ResultsCompared with the non-DM group (n=847), patients with DM (n=235) were older, exhibited higher mortality, and required more intensive care. Even after PS-matching, patients with DM exhibited more severe disease, and DM remained a prognostic factor for higher mortality (hazard ratio, 2.40; 95% confidence interval, 1.38 to 4.15). Subgroup analysis revealed that the presence of DM was associated with higher mortality, especially in older people (≥70 years old). Prior use of a dipeptidyl peptidase-4 inhibitor or a renin-angiotensin system inhibitor did not affect mortality or the clinical severity of the disease.ConclusionDM is a significant risk factor for COVID-19 severity and mortality. Our findings imply that COVID-19 patients with DM, especially if elderly, require special attention and prompt intensive care.

This paper presents a wearable multi-biosignal wireless interface for sleep analysis. It enables comfortable sleep monitoring with direct sleep-stage classification capability while conventional analytic interfaces including the Polysomnography (PSG) require complex post-processing analyses based on heavy raw data, need expert supervision for measurements, or do not provide comfortable fit for long-time wearing. The proposed multi-biosignal interface consists of electroencephalography (EEG), electromyography (EMG), and electrooculography (EOG). A readout integrated circuit (ROIC) is designed to collect three kinds of bio-potential signals through four internal readout channels, where their analog feature extraction circuits are included together to provide sleep-stage classification directly. The designed multi-biosignal sensing ROIC is fabricated in a 180-nm complementary metal-oxide-semiconductor (CMOS) process. For system-level verification, its low-power headband-style analytic device is implemented for wearable sleep monitoring, where the direct sleep-stage classification is performed based on a decision tree algorithm. It is functionally verified by comparison experiments with post-processing analysis results from the OpenBCI module, whose sleep-stage detection shows reasonable correlation of 74% for four sleep stages.

The uncertainties of four-dimensional computed tomography (4DCT), also called as residual motion artefacts (RMA), induced from irregular respiratory patterns can degrade the quality of overall radiotherapy. This study aims to quantify and reduce those uncertainties. A comparative study on quantitative indicators for RMA was performed, and based on this, we proposed a new 4DCT sorting method that is applicable without disrupting the current clinical workflow. In addition to the default phase sorting strategy, both additional amplitude information from external surrogates and the quantitative metric for RMA, investigated in this study, were introduced. The comparison of quantitative indicators and the performance of the proposed sorting method were evaluated via 10 cases of breath-hold (BH) CT and 30 cases of 4DCT. It was confirmed that N-RMSD (normalised root-mean-square-deviation) was best matched to the visual standards of our institute's regime, manual sorting method, and could accurately represent RMA. The performance of the proposed method to reduce 4DCT uncertainties was improved by about 18.8% in the averaged value of N-RMSD compared to the default phase sorting method. To the best of our knowledge, this is the first study that evaluates RMA indicators using both BHCT and 4DCT with visual-criteria-based manual sorting and proposes an improved 4DCT sorting strategy based on them.

The purpose of the study was to examine the development of a multiple linear regression model to estimate heart rate variability (HRV) parameters using easy-to-measure independent variables in preliminary experiments. HRV parameters (time domain: SDNN, RMSSD, NN50, pNN50; frequency domain: TP, VLF, LF, HF) and the independent variables (e.g., sex, age, body height, body weight, BMI, HR, HR max , HRR) were measured in 75 healthy adults (male n = 27, female n = 48) for estimating HRV. The HRV estimation multiple linear regression model was developed using the backward elimination technique. The regression model’s coefficient of determination for the time domain variables was significantly high (SDNN = R 2 : 72.2%, adjusted R 2 : 69.8%, P < .001; RMSSD = R 2 : 93.1%, adjusted R 2 : 92.1%, P < .001; NN50 = R 2 : 78.0%, adjusted R 2 : 74.9%, P < .001; pNN50 = R 2 : 89.1%, adjusted R 2 : 87.4%, P < .001). The coefficient of determination of the regression model for the frequency domain variable was moderate (TP = R 2 : 75.6%, adjusted R 2 : 72.6%, P < .001; VLF = R 2 : 41.6%, adjusted R 2 : 40.3%, P < .001; LF = R 2 : 54.6%, adjusted R 2 : 49.2%, P < .001; HF = R 2 : 67.5%, adjusted R 2 : 63.4%, P < .001). The coefficient of determination of time domain variables in the developed multiple regression models was shown to be very high (adjusted R 2 : 69.8%–92.1%, P < .001), but the coefficient of determination of frequency domain variables was moderate (adjusted R 2 : 40.3%–72.6%, P < .001). In addition to the equipment used for measuring HRV in clinical trials, this study confirmed that simple physiological variables could predict HRV.

The early-stage M23C6 morphology at the phase boundary between austenite and δ ferrite grain in Type 304L austenitic stainless steel was investigated with transmission electron microscopy (TEM). The M23C6 has coherency with austenite grains at phase boundary. The phase boundary between the M23C6 and austenite grains has curved appearance. The curved phase boundary might be a faceted interface composed of (111) plane and the other low-index planes on the atomic scale. The M23C6 morphology at the phase boundary was identified to be a complex pyramid-like shape that has {111}, {110} and {100} interfaces. The slight deviation in the angle measured between edges of carbide in the TEM images from that calculated between edges expected from the M23C6 morphology might be attributed to multilayer growth in the interior region of the M23C6 face.

This study aimed to investigate the effects of acute moderate hypoxia (HYP), compared with those of normoxia (NORM), during endurance exercise with the same HR level on metabolic function, skeletal muscle oxygenation, and cardiac function. Twelve healthy men (aged 25.1 ± 2.3 years) completed 30 min of endurance exercise using a cycle ergometer with the same HR level (136.5 ± 1.5 bpm) corresponding to 70% maximal heart rate (HRmax) under NORM (760 mmHg) and HYP (526 mmHg, simulated 3000 m altitude) after a 30 min exposure in the respective environments on different days, in random order. Exercise load, rating of perceived exertion (RPE), metabolic function (saturation of percutaneous oxygen; SpO2, minute ventilation; oxygen uptake; VO2, carbon dioxide excretion; respiratory exchange ratio; RER, and oxygen pulse), skeletal muscle oxygen profiles (oxyhemoglobin, oxhb, deoxyhemoglobin, dxhb, total hemoglobin, and tissue oxygenation index; StO2), and cardiac function (heart rate, stroke volume, cardiac output, end-diastolic volume, end-systolic volume, and ejection fraction) were measured during endurance exercise. HYP showed a lower exercise load with the same RPE during exercise than did NORM. In addition, HYP showed a lower SpO2, VO2, oxygen pulse, oxhb, and StO2, and a higher RER and dxhb during exercise than NORM. We found that HYP showed lower exercise load and VO2 at the same RPE than NORM and also confirmed a higher anaerobic metabolism and oxygen inflow into skeletal muscle tissue due to the limitation of oxygen delivery capacity.

This study aimed to analyze the status of sarcopenia, obesity, osteoporosis, and cardiometabolic disease according to the level of physical activity (PA) among elderly people in Korea. Among the data obtained from the National Health and Nutrition Survey (2008–2011), we analyzed the data of a total of 3,573 Korean elderly people over 65 years of age who were surveyed for dual X-ray absorptiometry (DXA) and PA. Higher levels of PA were associated with a lower prevalence of cardiometabolic disease (χ2 = 33.865, p < 0.001), osteoporosis (χ2 = 94.198, p < 0.001), sarcopenia, obesity, and sarcopenic obesity (χ2 = 71.828, p < 0.001). Above moderate-active PA was associated with lower body weight (p < 0.001), body fat mass (p < 0.001), and percent body fat (p < 0.001), and higher free-fat mass (p < 0.001) and appendicular skeletal muscle mass (ASM) (p < 0.001) than in low-active PA. In addition, when high-active is the risk factors of cardiometabolic were lower in waist circumference (p = 0.001), total cholesterol (TC) (p = 0.015), and triglyceride (TG) (p < 0.001) than low- and moderate-active PA, and higher in high-density lipoprotein cholesterol (HDL-C) (p < 0.001). The prevalence of cardiometabolic diseases was significantly decreased in high-active PA (odds ratio (OR) 0.60, 95% confidence interval (CI) 0.50–0.71); waist circumference (OR 0.85, 95% CI, 0.73–0.99; OR 0.59, 95% CI, 0.50–0.70) and HDL-C (OR 0.76, 95% CI, 0.65–0.88; OR 0.56, 95% CI, 0.47–0.67) significantly improved in moderate- and high-active PA, respectively, and TG (0.67 95% CI, 0.55–0.80) significantly improved in high-active PA. Osteoporosis (OR 0.62, 95% CI, 0.53–0.74; OR 0.46, 95% CI, 0.38–0.55) and sarcopenia (OR 0.77, 95% CI, 0.60–0.98; OR 0.73, 95% CI, 0.57–0.93) were significantly improved in moderate- and high-active PA, respectively. The incidence of obesity (OR 0.47, 95% CI, 0.39–0.57) and sarcopenic obesity (OR 0.47, 95% CI, 0.30–0.75) were significantly decreased in high-active PA. Therefore, we verified a lower prevalence of sarcopenia, osteoporosis, obesity, and cardiac metabolic disease in Korean elderly with more active PA. This suggests that more active PA maybe reduce the prevalence of sarcopenia, osteoporosis, obesity, and cardiometabolic diseases in older adults.

This work aims to establish a model of a primary water stress corrosion crack growth rate of Alloy 690 material for the head penetration nozzles of Korean pressurized water reactors. The test material had an inhomogeneous microstructure with bands of fine-grains and intragranular carbides in the matrix of coarse-grains, which was similar to the archive materials of the head penetration nozzles. The crack growth rate was measured from the strain-hardened materials as a function of the stress intensity factor in simulated primary water at various temperatures and dissolved hydrogen contents. The effects of strain-hardening, temperature, and dissolved hydrogen on the crack growth rate were analyzed independently, and were then introduced as normalizing factors in the crack growth rate model. The crack growth rate model proposed in this work provides a key element of the tools needed to assess the progress of a stress corrosion crack when detected in thick-wall Alloy 690 components in Korean reactors. Keywords: Alloy 690, Crack growth rate, Hybrid model, Primary water, Strain rate theory, Stress corrosion cracking

Identification of lower extremity misalignment requires radiation exposure and complex imaging. We developed and tested a smartphone application to facilitate quick identification of misalignment using photographs. Lower extremity alignment was measured by two independent researchers using a proprietary smartphone application and conventional radiographs. The results were compared between the methods and evaluators for interrater and intrarater reliability. Ninety datasets were obtained from 45 patients, with 90 lower extremity alignment angles measured via radiographs and the smartphone application. The intrarater reliability of the hip–knee–ankle angle (HKAA), measured twice by evaluator A using the radiographic imaging program, was 0.985, whereas that measured by evaluator B was 0.995. The intrarater reliability of the predicted lower extremity alignment angle (PLEAA) measured using the smartphone application was 0.970 and 0.968 for evaluators A and B, respectively. Thus, all results showed excellent reliability. In validity analysis, the correlation between PLEAA and HKAA measured twice by evaluators A and B was analyzed using Pearson’s correlation coefficient. HKAA (A) and PLEAA (A) had a positive correlation coefficient of 0.608 (p < 0.01), whereas HKAA (B) and PLEAA (B) had a positive correlation coefficient of 0.627 (p < 0.01). Thus, our smartphone application can facilitate for self-diagnosis of lower extremity misalignment.

Continuous health care and the measurement of health-related physical fitness (HRPF) is necessary for prevention against chronic diseases; however, HRPF measurements including laboratory methods may not be practical for large populations owing to constraints such as time, cost, and the requirement for qualified technicians. This study aimed to develop a multiple linear regression model to estimate the HRPF of Korean adults, using easy-to-measure dependent variables, such as gender, age, body mass index, and percent body fat. The National Fitness Award datasets of South Korea were used in this analysis. The participants were aged 19–64 years, including 319,643 male and 147,600 females. HRPF included hand grip strength (HGS), flexibility (sit and reach), muscular endurance (sit-ups), and cardiorespiratory fitness (estimated VO2max). An estimation multiple linear regression model was developed using the stepwise technique. The outlier data in the multiple regression model was identified and removed when the absolute value of the studentized residual was ≥2. In the regression model, the coefficient of determination for HGS (adjusted R2: 0.870, P < 0.001), muscular endurance (adjusted R2: 0.751, P < 0.001), and cardiorespiratory fitness (adjusted R2: 0.885, P < 0.001) were significantly high. However, the coefficient of determination for flexibility was low (adjusted R2: 0.298, P < 0.001). Our findings suggest that easy-to-measure dependent variables can predict HGS, muscular endurance, and cardiorespiratory fitness in adults. The prediction equation will allow coaches, athletes, healthcare professionals, researchers, and the general public to better estimate the expected HRPF.

Early- and late-onset Alzheimer’s disease (AD) patients often exhibit distinct features. We sought to compare overall white matter connectivity and evaluate the pathological factors (amyloid, tau, and vascular pathologies) that affect the disruption of connectivity in these two groups. A total of 50 early- and 38 late-onset AD patients, as well as age-matched cognitively normal participants, were enrolled and underwent diffusion-weighted magnetic resonance imaging to construct fractional anisotropy-weighted white matter connectivity maps. [18F]-THK5351 PET, [18F]-Flutemetamol PET, and magnetic resonance imaging were used for the evaluation of tau and related astrogliosis, amyloid, and small vessel disease markers (lacunes and white matter hyperintensities). Cluster-based statistics was performed for connectivity comparisons and correlation analysis between connectivity disruption and the pathological markers. Both patient groups exhibited significantly disrupted connectivity compared to their control counterparts with distinct patterns. Only THK retention was related to connectivity disruption in early-onset AD patients, and this disruption showed correlations with most cognitive scores, while late-onset AD patients had disrupted connectivity correlated with amyloid deposition, white matter hyperintensities, and lacunes in which only a few cognitive scores showed associations. These findings suggest that the pathogenesis of connectivity disruption and its effects on cognition are distinct between EOAD and LOAD.

Cardiovascular diseases (CVDs) are recognized as one of the major causes of morbidity and mortality worldwide. Generally, most CVDs can be prevented by addressing behavioral risk factors, including smoking, unhealthy diet and obesity, lack of physical activity, and alcohol abuse. Therefore, it is important to have a healthy lifestyle by performing regular physical activity to improve cardiovascular health and diseases. However, a majority of adults worldwide do not meet the minimum recommendations for regular aerobic exercise, and overweight and obesity ratio continues to rise. In addition, obese individuals, with a high prevalence of CVDs, have a lower participation rate for exercise because of the strain on the musculoskeletal system. Hypoxic therapy, including exposure or exercise intervention under hypoxia, has been utilized as a new therapeutic modality for cardiovascular benefit and amelioration of CVDs. Hypoxic therapy shows various physiological and pathophysiological properties, including increased appetite suppression and dietary intake reduction, increased energy consumption, improved glycogen storage, enhanced fatty acid oxidation, improved myocardial angiogenesis or ventricular remodeling, augmentation of blood flow within the skeletal muscle vascular beds, and reduction of the burden on the musculoskeletal system making it applicable to patients with CVDs and obesity with attenuated cardiovascular function. In particular, hypoxic therapy is very effective in improving cardiovascular benefits and preventing CVDs by enhancing arterial function, vascular endothelial function, and hemorheological properties. These observations indicate that hypoxic therapy may be an important and essential strategy for improving cardiovascular health and reducing cardiovascular morbidity and mortality.

Female endocrinological symptoms, such as premature ovarian inefficiency (POI) are caused by diminished ovarian reserve and chemotherapy. The etiology of POI remains unknown, but this can lead to infertility. This has accelerated the search for master regulator genes or other molecules that contribute as enhancers or silencers. The impact of regulatory microRNAs (miRNAs) on POI has gained attention; however, their regulatory function in this condition is not well known. RNA sequencing was performed at four stages, 2-(2 W), 6-(6 W), 15-(15 W), and 20-(20 W) weeks, on ovarian tissue samples and 5058 differentially expressed genes (DEGs) were identified. Gene expression and enrichment were analyzed based on the gene ontology and KEGG databases, and their association with other proteins was assessed using the STRING database. Gene set enrichment analysis was performed to identify the key target genes. The DEGs were most highly enriched in 6 W and 15 W groups. Figla, GDF9, Nobox, and Pou51 were significantly in-creased at 2 W compared with levels at 6 W and 20 W, whereas the expression of Foxo1, Inha, and Taf4b was significantly de-creased at 20 W. Ccnd2 and Igf1 expression was maintained at similar levels in each stage. In total, 27 genes were upregulated and 26 genes interacted with miRNAs; moreover, stage-specific upregulated and downregulated interactions were demonstrated. Increased and decreased miRNAs were identified at each stage in the ovaries. The constitutively expressed genes, Ccnd2 and Igf1, were identified as the major targets of many miRNAs (p < 0.05), and Fshr and Foxo3 interacted with miRNAs, namely mmu-miR-670-3p and mmu-miR-153-3p. miR-26a-5p interacted with Piwil2, and its target genes were downregulated in the 20 W mouse ovary. In this study, we aimed to identify key miRNAs and their target genes encompassing the reproductive span of mouse ovaries using mRNA and miRNA sequencing. These results indicated that gene sets are regulated in the reproductive stage-specific manner via interaction with miRNAs. Furthermore, consistent expression of Ccnd2 and Igf1 is considered crucial for the ovarian reserve and is regulated by many interactive miRNAs.

Traditional ultrasonic imaging methods have a low accuracy in the localization of defects in austenitic welds because the anisotropy and inhomogeneity of the welds cause distortion of the ultrasonic wave propagation paths in anisotropic media. The distribution of the grain orientation in the welds influences the ultrasonic wave velocity and ultrasonic wave propagation paths. To overcome this issue, a finite element analysis (FEA)-based ultrasonic imaging methodology for austenitic welds is proposed in this study. The proposed ultrasonic imaging method uses a wave propagation database to synthetically focus the inter-element signal recorded with a phased array system using a delay-and-sum strategy. The wave propagation database was constructed using FEA considering the grain orientation distribution and the anisotropic elastic constants in the welds. The grain orientation was extracted from a macrograph obtained from a dissimilar metal weld specimen, after which the elastic constants were optimized using FEA with grain orientation information. FEA was performed to calculate a full matrix of time-domain signals for all combinations of the transmitting and receiving elements in the phased array system. The proposed approach was assessed for an FEA-based simulated model embedded in a defect. The simulation results proved that the newly proposed ultrasonic imaging method can be used for defect localization in austenitic welds.

Fertility preservation is an emerging discipline, which is of substantial clinical value in the care of young patients with cancer. Chemotherapy and radiation may induce ovarian damage in prepubertal girls and young women. Although many studies have explored the mechanisms implicated in ovarian toxicity during cancer treatment, its molecular pathophysiology is not fully understood. Chemotherapy may accelerate follicular apoptosis and follicle reservoir utilization and damage the ovarian stroma via multiple molecular reactions. Oxidative stress and the radiosensitivity of oocytes are the main causes of gonadal damage after radiation treatment. Fertility preservation options can be differentiated by patient age, desire for conception, treatment regimen, socioeconomic status, and treatment duration. This review will help highlight the importance of multidisciplinary oncofertility strategies for providing high-quality care to young female cancer patients.

Background Recently, gut microbiota have been studied extensively for health promotion, disease prevention, disease treatment, and exercise performance. It is recommended that athletes avoid dietary fiber and resistant starch to promote gastric emptying and reduce gastrointestinal distress during exercise, but this diet may reduce microbial diversity and compromise the health of the athlete’s gut microbiota. Objective This study compared fecal microbiota characteristics using high-throughput sequencing among healthy sedentary men (as controls), bodybuilders, and distance runners, as well as the relationships between microbiota characteristics, body composition, and nutritional status. Methods Body composition was measured using DXA, and physical activity level was assessed using IPAQ. Dietary intake was analyzed with the computerized nutritional evaluation program. The DNA of fecal samples was extracted and it was sequenced for the analysis of gut microbial diversity through bioinformatics cloud platform. Results We showed that exercise type was associated with athlete diet patterns (bodybuilders: high protein, high fat, low carbohydrate, and low dietary fiber diet; distance runners: low carbohydrate and low dietary fiber diet). However, athlete type did not differ in regard to gut microbiota alpha and beta diversity. Athlete type was significantly associated with the relative abundance of gut microbiota at the genus and species level: Faecalibacterium, Sutterella, Clostridium, Haemophilus, and Eisenbergiella were the highest (p

This study examined the effects of high-impact weight-bearing exercise on bone mineral density (BMD) and bone metabolic markers in middle-aged premenopausal women. Forty middle-aged premenopausal women were initially enrolled, but thirty-one participants (40.34 ± 3.69 years) completed in the study. The subjects were randomly divided into two groups including the high-impact weight-bearing exercise group (HWE, n = 14) and control group (CON, n = 17). The HWE group participated in the exercise for 50 min a day, three days per week for four months, while the CON group maintained their regular lifestyle. The HWE program included 10 different high-impact weight-bearing exercises such as jumping and running. BMD was measured using DXA (Hologic, QDR 4500W, Marlborough, MA, USA). The bone metabolic markers including serum 25-(OH) D, intact parathyroid hormone (PTH), osteoprotegerin (OPG), osteopontin (OPN), receptor activator of nuclear factor κB ligand (RANKL), osteocalcin (OC), C-terminal telopeptide of type 1 collagen (CTX), and calcium were analyzed. The results showed that the BMDs of femur, lumbar, and forearm did not significantly change during the intervention period in both the HWE and CON groups. A significant decrease in bone formation markers such as OC (F = 10.514, p = 0.003, ηp2 = 0.266) and an increase in bone resorption marker including CTX (F = 8.768, p = 0.006, ηp2 = 0.232) were found only in the CON group, while these values did not change in the HWE group. There was a significant increase in serum 25-(OH) D (F = 4.451, p = 0.044, ηp2 = 0.133) in the HWE group. Our findings suggest that four months of HWE is not sufficient to improve BMD and bone metabolic markers, but this impact exercise program may prevent the age-associated changes in bone turnover markers in middle-aged premenopausal women.