Significant CO2 emission in the shallow inshore waters of the southeastern Yellow Sea in 2020.

This study investigated the carbonate system and air-sea CO2 exchange in the inshore waters along South Korea's western coastline in 2020. Overlooking these waters might introduce significant errors in estimating air-sea CO2 fluxes of the southeastern Yellow Sea, given their interaction with land, offshore regions, and sediments. During periods other than summer, seasonal variations in seawater CO2 partial pressure (pCO2) could be generally explained by thermal effects. Tidal mixing and shallow depths resulted in weaker stratification-induced carbon export compared to offshore regions. However, during summer, inshore waters exhibited high spatial variability in pCO2, ranging from approximately 185 to 1000 µatm. In contrast to offshore waters that modestly absorbed CO2, inshore waters shallower than 20 m emitted ∼100 Gg C yr-1 to the atmosphere. However, considering the high heterogeneity of the study area, additional observations with high spatial and temporal resolution are required to refine estimates of air-sea CO2 exchange.

Influence of the Hawthorne effect on spatiotemporal parameters, kinematics, ground reaction force, and the symmetry of the dominant and nondominant lower limbs during gait.

The Hawthorne effect is a change in behavior resulting from awareness of being observed or evaluated. This study aimed to determine whether awareness of being evaluated or presence of an observer influence gait. Twenty-one young women were asked to walk in three conditions. In the first condition (unawareness of evaluation; UE), participants were aware that it was a practice trial, and there was no observer. In the second condition (awareness of evaluation; AE), participants were aware that their gait was being evaluated. The third condition (AE + researcher observation; RO) was similar to the second condition except that an additional researcher observed the participant' gait. The spatiotemporal, kinematic, ground reaction forces, and ratio index (symmetry of both lower limbs) were compared among the three conditions. A higher ratio index indicated a relative increase in the value on left versus right. Gait speed (P = 0.012) and stride length (right and left; P = 0.006 and 0.007, respectively) were significantly increased in the AE + RO than in UE. Range of motion of the right hip and left ankle was significantly greater in AE than in UE (P = 0.039 and 0.012, respectively). The ratio index of ground reaction force during push-off was significantly higher in AE and AE + RO conditions than in UE (P < 0.001 and P = 0.004, respectively). The Hawthorne effect (awareness of being evaluated or presence of an observer) potentially influences gait. Thus, factors that influence gait analysis should be considered when evaluating normal gait.

Comparing the Impact of Upper Body Control and Core Muscle Stabilization Training on Landing Biomechanics in Individuals with Functional Ankle Instability: A Randomized Controlled Trial.

Functional ankle instability (FAI), which is characterized by recurrent ankle sprains and perceived joint instability, arises from various factors contributing to compromised biomechanical control during activities, particularly those involving landing tasks. While current research predominantly addresses lower-extremity and core stabilization interventions for FAI, the contribution of upper body control to landing biomechanics in this population remains insufficiently explored. In this study, 42 participants (19 males, 23 females) with FAI were randomly assigned to either the upper-body control training group (UBCTG) or the core muscle stabilization training group (CMSTG). The groups underwent six-week interventions, with the UBCTG receiving a dynamic core exercise program including upper body control and the CMSTG receiving static core muscle training. Pre- and post-intervention assessments encompassed electromyography of the gastrocnemius, tibialis anterior, and peroneus longus, motion analysis of the lower extremities, and ground reaction force (GRF) readings during a single-leg-jump task. Additionally, dynamic balance was assessed using the Y balance test and self-reported measurements of ankle instability were performed. The results showed similar increases in muscle activation, joint movement, and self-reported ankle instability scores within both groups. However, significant between-group differences were observed in terms of knee flexion angle, dynamic balance, and ankle instability scores, favoring the UBCTG. Although the peak vertical GRF significantly decreased and the time to peak vertical GRF increased in both groups, more changes were noted in the UBCTG. Our results demonstrated that dynamic core exercises with additional upper body control training enhance landing biomechanics, dynamic balance, and stability in individuals with FAI. Consequently, we recommend incorporating shoulder girdle exercises, proprioceptive drills, and balance exercises into dynamic core training.

Effects of Augmented Reality Game-Based Cognitive-Motor Training on Restricted and Repetitive Behaviors and Executive Function in Patients with Autism Spectrum Disorder.

Restricted and repetitive behaviors (RRBs) and executive dysfunction are widely acknowledged as core features and hallmarks in patients with autism spectrum disorder (ASD). This study aimed to investigate the effects of augmented reality (AR) using motivational games with cognitive-motor exercises on RRBs, executive function (EF), attention, and reaction time in patients with ASD. Twenty-four patients (range from 6 to 18 years) diagnosed with ASD were recruited from local social welfare centers and randomly allocated to the AR game-based cognitive-motor training group (study group) or the conventional cognitive training group (control group). Both groups completed 30 min training sessions, twice a week for four weeks. Outcome measures were conducted before and after the intervention. As a result, improvements were observed in all the subscales of the RRBs in the study group except for self-injurious and ritualistic behavior. Significant improvements were observed in EF and reaction time in the study group, which was significantly higher compared to the control group. With the present findings, we can suggest that cognitive-motor training using AR game-based content generates positive effects on improving executive function reaction time and accuracy of responses and has a limited effect on RRBs in patients with ASD. This can be proposed as a complementary intervention associated with individualized daily management.

Effects of Augmented Reality-Based Dual-Task Program on Physical Ability by Cognitive Stage with Developmental Disabilities.

People diagnosed with developmental disabilities are less likely to participate in physical activities even if they are provided opportunities. This study aimed to examine the effects of dual-task exercise-based augmented reality (AR) on muscle strength, muscle endurance, balance ability, and flexibility among people with developmental disabilities. Twenty-seven patients with developmental disabilities were included in the study. The intervention was based on an AR-based rehabilitation program and lasted for 8 weeks. The results showed a statistically significant improvement in muscle strength, muscle endurance, balance ability, and flexibility after the intervention (p < 0.05). The AR-based dual-task program increased interest and motivation in the high-cognitive-stage groups, while less interest and motivation were observed in the low-cognitive-stage groups. Our results suggest that an AR-based dual-task program can be an effective method to improve physical ability in patients with high cognitive levels.

Comparison of screw-home movement between patients with knee osteoarthritis and normal adults.

BACKGROUND: Tibial rotation accompanying sagittal movement contains the phenomenon of screw-home movement (SHM) of the knee, which plays an important role in knee stability during extension. OBJECTIVE: This study aimed to investigate the change of SHM in patients with knee osteoarthritis (OA). METHODS: Thirty-one sex-matched patients with knee OA and 31 normal subjects were recruited. The total tibial rotation was obtained during knee sagittal movement (extension and flexion) using an inertial measurement unit. The acquired angle of tibial rotation was divided into eight periods. The total tibial rotation and the variation of each period were compared between the OA and control groups. The difference in tibial rotation according to Kellgren-Lawrence (KL) grade was compared. RESULTS: The total tibial rotation of the OA group decreased compared with the control group during knee extension and flexion (P< 0.001). Variations of tibial rotation were significantly different between groups in all periods (P< 0.001) except for knee extension at 70∘ to 45∘ (P= 0.081). There was no significant difference in tibial rotations among the KA grades of OA patients. CONCLUSION: We found a reduction in the total tibial rotation and loss of the SHM in the unloaded OA knee. It could be predicted that reduced SHM appeared early in knee OA.

Reliability, minimum detectable change, and minimum clinically important difference of the balance subtest of the Bruininks-Oseretsky test of motor proficiency-second edition in children with cerebral palsy.

PURPOSE: This study aimed to investigate the internal consistency, inter-rater, and test-retest reliability of the balance subtest of the Bruininks-Oseretsky test of motor proficiency-second edition (BOT-2) and to estimate the minimum detectable change (MDC) and minimum clinically important difference (MCID) of the balance subtest of the BOT-2 in children with cerebral palsy (CP). METHODS: In total, 20 children with CP participated in the present study. Internal consistency, test-retest, and inter-rater reliability were computed to establish reliability of the balance subtest of the BOT-2. The MDC95 was estimated from the standard error of measurement (SEM) to determine a real change for an individual child with CP. The anchor- and distribution-based MCID were calculated to determine the smallest change that might be important to clinicians. For concurrent validity, the correlation between the balance subtest of the BOT-2 and the pediatric balance scale (PBS) were calculated using Spearman's correlation. RESULTS: Internal consistency was good (Cronbach's alpha coefficient = 0.89). The BOT-2 had excellent test-retest (ICC = 0.99, p < 0.001) and inter-rater reliability (ICC = 0.99, p < 0.001). The balance subtest of the BOT-2 had an SEM of 0.70, MDC95 of 9.61, and MCIDs of 2.54 (anchor-based) and 1.38 (distribution-based). Additionally, there was a moderate positive correlation between the balance subtest of the BOT-2 and the PBS (Spearman's rho = 0.629, p = 0.003). CONCLUSIONS: Our experimental results indicate that the balance subtest of the BOT-2 had good internal consistency, along with excellent test-retest and inter-rater reliability. The change in scores of an individual child with CP should attain 9.61 points on the balance subtest of the BOT-2 to indicate a clinically important change. The MDC95 and MCID values could be helpful in understanding therapeutic effects and evaluating balancing ability using the balance subtest of the BOT-2 in children with CP.

Variability in blue carbon storage related to biogeochemical factors in seagrass meadows off the coast of the Korean peninsula.

Coastal vegetated habitats such as mangroves, salt marshes, and seagrasses, referred to as blue carbon ecosystems, play an important role in climate change mitigation by an effective CO2 capture from atmosphere and water columns and long-term organic carbon (Corg) storage in sediments. Although seagrass meadows are considered intense carbon sinks, information on regional variability in seagrass blue carbon stock and factors influencing its capacity still remain sparse. In the present study, seagrass blue carbon storage by measuring Corg stocks in sediments and living seagrass biomass, and carbon accumulation rates (CARs) in seagrass meadows were estimated along the Korean coast. Factors affecting variability in Corg stocks were also analyzed using partial least squares (PLS) regression and principal component analysis (PCA). Projected Corg stocks in sediment, extrapolated to a depth 1 m, exhibited substantial variability among sites, ranging from 49.91 to 125.71 Mg C ha-1. The majority of Corg (96-99%) was stored in sediments, whereas the contribution of living biomass was minor. PLS regression and PCA indicated that Corg stocks in seagrass meadows are strongly associated with sediment characteristics such as dry bulk density and water and mud content. Among seagrass traits, above- to below-ground biomass ratio was significantly related to the quantity of Corg stocks in seagrass meadows. Because of the high spatial variability in Corg stocks and CARs, local and regional differences in seagrass blue carbon storage should be considered to accurately assess the climate change mitigation potential of seagrass ecosystems.

The first national scale evaluation of organic carbon stocks and sequestration rates of coastal sediments along the West Sea, South Sea, and East Sea of South Korea.

Blue carbon science requires the estimates of organic carbon stock and sequestration rate; however, holistic data analysis remains limited in South Korea. The present study reports current organic carbon stocks and sequestration rates in the coastal areas of West Sea, South Sea, and East Sea of South Korea, encompassing entire intertidal areas using long-term field survey combined with remote sensing technology. Twenty-one intertidal flats were targeted across seven provinces (Gyeonggi, Chungnam, Jeonbuk, Jeonnam, Gyeongnam, Gyeongbuk, Gangwon). Out of the evaluated environmental parameters, mud content represented a significant factor controlling sedimentary organic carbon stocks across target areas, and was significantly positively correlated to the total organic carbon (p < 0.05). Organic carbon stocks measured in salt marshes (i.e., upper intertidal zone) reflected the high carbon fixation capacity of halophytes through primary production. Sediment textural type was classified using analysis of remotely sensed imagery, and was closely correlated to field-based classification data (p < 0.05). Using field and remote sensing results, we estimated total organic carbon stocks (13,142,149 Mg C) and sequestration rates (71,383 Mg C yr-1) in the tidal flats of South Korea. This study presents the first report on blue carbon potential in the Korean tidal flats, providing baseline information on the carbon dynamics of intertidal sediments in this region and, potentially, elsewhere.

Spatial distribution and pollution assessment of metals in intertidal sediments, Korea.

We measured the concentrations of acid volatile sulfide (AVS), chemical oxygen demand (COD), and metals (As, Cd, Cu, Hg, Pb, and Zn) in surface sediments of 74 intertidal sectors along the western and southern coasts of Korea to determine their spatial distribution and pollution status. The concentrations of AVS, COD, and metals were relatively higher in northwestern and southeastern coasts due to human and industrial activities around metropolitan, industrial complexes, and large-scale farms. The results of the sediment quality guidelines and geoaccumulation index for organic matter and metal revealed that almost all intertidal sediments were unpolluted with regard to AVS, COD, Cd, Cu, Hg, Pb, and Zn and some intertidal sediments in northwestern and southeastern coasts were moderately polluted with regard to As. However, the results of pollution load index and ecological risk index for metal showed that intertidal sediments in the southeastern coast are significantly polluted and could have an adverse effect on benthic organisms. Thus, the appropriate management policy and restoration plan for intertidal sectors with high metal pollution level in Korea is necessary to improve the quality of intertidal sediment.

Forward head posture (FHP) angle and plantar pressure resulting from oscillatory stimulation training of the shoulder joint: A randomized controlled trial.

BACKGROUND: Oscillatory stimulation provides strong sensory stimulation, which can activate muscle spindles, strengthening proprioceptive sense and, therefore, helping to strengthen the muscles involved in posture stability. OBJECTIVE: This study aimed to investigate the difference in average distribution of plantar pressure resulting from changes in the forward head position (FHP) angle caused by controlling muscle activity in the neck and shoulders through Bodyblade. METHODS: The subjects were divided into an experimental group (Bodyblade, n= 15) and a control group (general physiotherapy, n= 15). Eighteen sessions of exercise were implemented. Craniovertebral angle (CVA) and cranial rotation angle (CRA) were measured to evaluate the change of FHP. The Gaitview AFA-50 (Alfoots Co, Korea) was used to measure the plantar pressure distribution. RESULTS: The experimental group showed a larger increase in CVA than the control group (p< 0.05). Only the experimental group showed a significant decrease in CRA (p< 0.05).Both the anterior pressure and posterior pressure showed a significant improvement only in the experimental group (p< 0.05). The experimental group showed a larger increase in anterior/posterior ratio than the control group (p< 0.05). CONCLUSIONS: Bodyblade improves the angle of FHP, thus positively affecting the average ratio of plantar pressure.

Study on the design development of a multi joint ankle foot orthosis.

[Purpose] The purpose of this study was to investigate the effects of a newly designed multi joint ankle-foot orthosis on the gait and dynamic balance of stroke patients having foot drop. [Participants and Methods] This study was investigated 10 participants who were diagnosed with stroke. Patients were evaluated based on a 10-meter walk test, timed up and go test and Berg balance scale after each participant wore a plastic ankle-foot orthosis and a multi joint ankle-foot orthosis (AFO) that consisted of orthosis joints (having poster-stop joint and Klenzak joint functions). [Results] The 10-meter walk test, timed up and go test and Berg balance scale showed significant differences in the orthosis with the Klenzak joint function. [Conclusion] The appropriate use of Klenzak AFO of the newly designed multi joint AFO is expected to have a positive effect on improving the gait and balancing ability of stroke patients having foot drop.

Effect of Ankle Range of Motion (ROM) and Lower-Extremity Muscle Strength on Static Balance Control Ability in Young Adults: A Regression Analysis.

BACKGROUND The purpose of this study was to investigate the effect of ankle ROM and lower-extremity muscle strength on static balance control ability in young adults. MATERIAL AND METHODS This study was conducted with 65 young adults, but 10 young adults dropped out during the measurement, so 55 young adults (male: 19, female: 36) completed the study. Postural sway (length and velocity) was measured with eyes open and closed, and ankle ROM (AROM and PROM of dorsiflexion and plantarflexion) and lower-extremity muscle strength (flexor and extensor of hip, knee, and ankle joint) were measured. Pearson correlation coefficient was used to examine the correlation between variables and static balance ability. Simple linear regression analysis and multiple linear regression analysis were used to examine the effect of variables on static balance ability. RESULTS In correlation analysis, plantarflexion ROM (AROM and PROM) and lower-extremity muscle strength (except hip extensor) were significantly correlated with postural sway (p<0.05). In simple correlation analysis, all variables that passed the correlation analysis procedure had significant influence (p<0.05). In multiple linear regression analysis, plantar flexion PROM with eyes open significantly influenced sway length (B=0.681) and sway velocity (B=0.011). CONCLUSIONS Lower-extremity muscle strength and ankle plantarflexion ROM influenced static balance control ability, with ankle plantarflexion PROM showing the greatest influence. Therefore, both contractile structures and non-contractile structures should be of interest when considering static balance control ability improvement.

Comparison of Hypertension Prediction Analysis Using Waist Measurement and Body Mass Index by Age Group.

OBJECTIVES: The purpose of this study was to evaluate hypertension with simple anthropometry data related to obesity in Korean adults and identify whether age specific waist circumference (WC) may be a useful screening tool for determining hypertension. METHODS: Subjects (n = 571) were classified into 3 groups by age; young (18-39 years), middle aged (40-64 years), and old aged (≥ 65 years). Correlations between demographic and anthropometric parameters and hypertension were performed using Spearman correlation analysis. Logistic regression analysis and ROC (receiver operating characteristics) curves were also analyzed for correlations with hypertension. RESULTS: Spearman correlation analyses, age, gender, WC, and body mass index were positively correlated with hypertension. When logistic regression analysis was performed, increased age and increased WC was associated with a higher incidence of hypertension, although gender and body mass index were not significantly related to hypertension. In ROC analysis of WC for hypertension demonstrated that patients in the old age group showed higher WC cutoff value than patients in the young and middle aged groups. CONCLUSION: The findings of this study demonstrate that WC may be a useful predictor of hypertension incidence among demographic and anthropometric factors in Korean adults. In addition, WC in the young population was more sensitive to the incidence of hypertension than in the elderly population.

The relationship between anterior pelvic tilt and gait, balance in patient with chronic stroke.

[Purpose] The aim of this study is to find out the association between anterior pelvic tilt and gait and balance in chronic stroke. [Subjects and Methods] Fourteen chronic stroke patients were included in this study. A palpation meter was employed to measure the anterior inclination of the pelvis. A GAITRite system automates measuring temporal and spatial gait parameters. A 10-Meter Walk test was used to measure gait speed. The Timed Up and Go test was used to measure the dynamic balance ability and gait ability of the participants. A BioRescue was used to assess balance by measuring the moving distance and area of the center of pressure. [Results] There were significant negative correlations between pelvic anterior tilt and velocity, step length, and stride. There were significant positive correlations between velocity and cadence, step length, and stride length. There were significant negative correlations between velocity and cycle time, H-H base, TUG, and 10MWT. There was significant negative correlation between cadence and cycle time and H-H base. [Conclusion] This study showed a negative correlation between pelvic anterior tilt and gait function including gait speed and step length.

Correlations among visual analogue scale, neck disability index, shoulder joint range of motion, and muscle strength in young women with forward head posture.

This study investigated the correlation between the neck disability index (NDI) and visual analogue scale (VAS), which are indicators of neck pain, shoulder joint range of motion (ROM), and muscle strength in women with a slight forward head posture. This study was carried out on 42 female college students attending Uiduk University in Gyeongju, Korea. The neck pain and disability index for each subject was measured using VAS and NDI, respectively. Two physiotherapists measured the shoulder joint ROM and muscle strengths of the subjects using a goniometer and a dynamometer, respectively. External rotation, internal rotation, and abduction of the shoulder joint were measured for each subject. A significant negative correlation between neck pain and shoulder joint ROM in external rotation and the muscle strength of the shoulder joint in abduction was found in the subjects. In addition, a significant positive correlation was observed between ROM in external rotation and muscle strength in abduction. This study showed a significant negative correlation between neck pain and ROM in external rotation as well as between neck pain and the muscle strength in abduction.

Correlation between Scapular Asymmetry and Differences in Left and Right Side Activity of Muscles Adjacent to the Scapula.

OBJECTIVES: The aim of this study was to analyze the correlation between scapular asymmetry in young female adults and differences in left and right side activity of muscles adjacent to the scapula. METHODS: This study included 60 female students from U university in Korea. In order to examine scapular asymmetry, the lateral scapular slide test (LSST) was used. The LSST was performed in 3 different postures (LSST-1, LSST-2, and LSST-3; i.e., 0°, 45°, and 90° of upper limb abduction, respectively). Muscle activity was measured during external and internal rotation of the shoulder joints. Muscle activity was measured at the upper, middle, and lower trapezius, and the serratus anterior. RESULTS: In external shoulder rotation, there was a significant correlation (R = 0.450) between LSST-2 and the middle trapezius. In internal shoulder rotation, there was a significant correlation (R = 0.472) between LSST-2 and the upper trapezius, and between LSST-3 and the lower trapezius (R = 0.657); these results demonstrated a moderate positive linear correlation. CONCLUSION: There was a positive correlation between left and right scapular asymmetry and the difference in left and right muscle activity of the trapezius in female adults. Problems in the trapezius may lead to scapular asymmetry.

Effects of skilled reach training with affected forelimb and treadmill exercise on the expression of neurotrophic factor following ischemia-induced brain injury in rats.

[Purpose] The aim of the present study was to investigate effects of skilled reach training with affected forelimb and treadmill exercise on the expression of neurotrophic factor following ischemia-induced brain injury in rats. [Subjects and Methods] Thirty male Sprague-Dawley rats were divided into 3 groups randomly: namely, the control sacrified 2 weeks after surgery, skilled reach training with forepaw contralateral to brain injury for 2 weeks, and treadmill exercise for 2 weeks. Transient focal cerebral ischemia was induced by intraluminal occlusion of the left middle cerebral artery. After that, skilled reach training and treadmill exercise were conducted. Western blot analysis was performed to investigate expressions of neurotrophic factors. [Results] There were significant differences in brain-derived neurotrophic factor and nerve growth factor expression between the control group and the experimental group. There were no significant differences in brain-derived neurotrophic factor and nerve growth factor expression between the skilled reach training group and the treadmill exercise group. [Conclusion] Skilled reach training and treadmill exercise can affect the expression of neurotrophic factors.

The effect of horse-riding simulator exercise on the gait, muscle strength and muscle activation in elderly people with knee osteoarthritis.

[Purpose] The aim of this study was to examine the effects of horse-riding simulator exercise on gait ability and muscle strength, muscle activation in elderly with knee osteoarthritis. [Subjects and Methods] Thirty elderly patients with knee osteoarthritis were recruited, a horse-riding simulator group consisted of fifteen subjects and they performed exercise three times a week for eight weeks. And each exercise was performed, horse riding simulator exercise for 15 minutes and knee strengthening exercise for 15 minutes. Knee strengthening exercise group consisted of fifteen subjects and performed knee strengthening exercise for 30 minutes. [Results] The horse-riding simulator group showed significant differences after the intervention in timed 10-meter walk test (10MWT), muscle strength, muscle activation. [Conclusion] The results of this study indicate that horse-riding simulator exercise is effective on knee osteoarthritis. Therefore, horse-riding simulator exercise can be used for gait training for knee osteoarthritis.

Analysis of the reliability of the make test in young adults by using a hand-held dynamometer.

[Purpose] The purpose of this study was to analyze intra-rater and inter-rater reliabilities of the make test, a manual muscle testing measurement method, using a hand-held dynamometer in Korean young adults. [Subjects and Methods] A total of 42 university students participated in this study. The make test, a manual muscle testing method, was conducted. A hand-held dynamometer was used to measure elbow joint flexion during the make test. [Results] Both intra-rater (the intraclass correlation coefficient=0.992) and inter-rater reliabilities (the intraclass correlation coefficient=0.949) were excellent, with values over 0.9. [Conclusion] The make test is a useful manual muscle testing method with high intra-rater and inter-rater reliability.