Reconstruction of magnetic island electron temperature in mixed second and third harmonic electron cyclotron emission conditions.

We develop a method to use the mixed third and second harmonic electron cyclotron emission (ECE) signal in the DIII-D tokamak to reconstruct the electron temperature profile of a rotating magnetic island. The third harmonic ECE is removed by extracting the rotating-island-associated fluctuations in the mixed signal, and the extracted fluctuation is combined with the equilibrium temperature obtained from other diagnostics after correcting for the third harmonic reabsorption. The accuracy of the reconstruction is studied by considering a DIII-D shot where an unmixed signal from an island is available on the low field side of the plasma and a mixed signal from the same island is available from the high field side. It is found that the reconstruction method successfully reproduces the island shape and temperature perturbation magnitude without the distortion caused by third harmonic ECE mixing. However, the radial location of the reconstructed island is somewhat displaced relative to the location of the q = 2 surface in the axisymmetric equilibrium reconstruction, resulting in a corresponding inaccuracy in the absolute temperature of the island. It is conjectured that this may arise from an inaccuracy of the reconstructed axisymmetric equilibrium in this region.

Gut microbiome predicts cognitive function and depressive symptoms in late life.

Depression in older adults with cognitive impairment increases progression to dementia. Microbiota is associated with current mood and cognition, but the extent to which it predicts future symptoms is unknown. In this work, we identified microbial features that reflect current and predict future cognitive and depressive symptoms. Clinical assessments and stool samples were collected from 268 participants with varying cognitive and depressive symptoms. Seventy participants underwent 2-year follow-up. Microbial community diversity, structure, and composition were assessed using high-resolution 16 S rRNA marker gene sequencing. We implemented linear regression to characterize the relationship between microbiome composition, current cognitive impairment, and depressive symptoms. We leveraged elastic net regression to discover features that reflect current or future cognitive function and depressive symptoms. Greater microbial community diversity associated with lower current cognition in the whole sample, and greater depression in participants not on antidepressants. Poor current cognitive function associated with lower relative abundance of Bifidobacterium, while greater GABA degradation associated with greater current depression severity. Future cognitive decline associated with lower cognitive function, lower relative abundance of Intestinibacter, lower glutamate degradation, and higher baseline histamine synthesis. Future increase in depressive symptoms associated with higher baseline depression and anxiety, lower cognitive function, diabetes, lower relative abundance of Bacteroidota, and lower glutamate degradation. Our results suggest cognitive dysfunction and depression are unique states with an overall biological effect detectable through gut microbiota. The microbiome may present a noninvasive readout and prognostic tool for cognitive and psychiatric states.

Pregnancy loss in major fetal congenital heart disease: incidence, risk factors and timing.

OBJECTIVE: Fetuses with congenital heart disease (CHD) are at increased risk of pregnancy loss compared with the general population. We aimed to assess the incidence, timing and risk factors of pregnancy loss in cases with major fetal CHD, overall and according to cardiac diagnosis. METHODS: This was a retrospective, population-level cohort study of fetuses and infants diagnosed with major CHD between 1997 and 2018 identified by the Utah Birth Defect Network (UBDN), excluding cases with termination of pregnancy and minor cardiovascular diagnoses (e.g. isolated aortic/pulmonary pathology and isolated septal defects). The incidence and timing of pregnancy loss were recorded, overall and according to CHD diagnosis, with further stratification based on presence of isolated CHD vs additional fetal diagnosis (genetic diagnosis and/or extracardiac malformation). Adjusted risk of pregnancy loss was calculated and risk factors were assessed using multivariable models for the overall cohort and prenatal diagnosis subgroup. RESULTS: Of 9351 UBDN cases with a cardiovascular code, 3251 cases with major CHD were identified, resulting in a study cohort of 3120 following exclusion of cases with pregnancy termination (n = 131). There were 2956 (94.7%) live births and 164 (5.3%) cases of pregnancy loss, which occurred at a median gestational age of 27.3 weeks. Of study cases, 1848 (59.2%) had isolated CHD and 1272 (40.8%) had an additional fetal diagnosis, including 736 (57.9%) with a genetic diagnosis and 536 (42.1%) with an extracardiac malformation. The observed incidence of pregnancy loss was highest in the presence of mitral stenosis (< 13.5%), hypoplastic left heart syndrome (HLHS) (10.7%), double-outlet right ventricle with normally related great vessels or not otherwise specified (10.5%) and Ebstein's anomaly (9.9%). The adjusted risk of pregnancy loss was 5.3% (95% CI, 3.7-7.6%) in the overall CHD population and 1.4% (95% CI, 0.9-2.3%) in cases with isolated CHD (adjusted risk ratio, 9.0 (95% CI, 6.0-13.0) and 2.0 (95% CI, 1.0-6.0), respectively, based on the general population risk of 0.6%). On multivariable analysis, variables associated with pregnancy loss in the overall CHD population included female fetal sex (adjusted odds ratio (aOR), 1.6 (95% CI, 1.1-2.3)), Hispanic ethnicity (aOR, 1.6 (95% CI, 1.0-2.5)), hydrops (aOR, 6.7 (95% CI, 4.3-10.5)) and additional fetal diagnosis (aOR, 6.3 (95% CI, 4.1-10)). On multivariable analysis of the prenatal diagnosis subgroup, years of maternal education (aOR, 1.2 (95% CI, 1.0-1.4)), presence of an additional fetal diagnosis (aOR, 2.7 (95% CI, 1.4-5.6)), atrioventricular valve regurgitation ≥ moderate (aOR, 3.6 (95% CI, 1.3-8.8)) and ventricular dysfunction (aOR, 3.8 (95% CI, 1.2-11.1)) were associated with pregnancy loss. Diagnostic groups associated with pregnancy loss were HLHS and variants (aOR, 3.0 (95% CI, 1.7-5.3)), other single ventricles (aOR, 2.4 (95% CI, 1.1-4.9)) and other (aOR, 0.1 (95% CI, 0-0.97)). Time-to-pregnancy-loss analysis demonstrated a steeper survival curve for cases with an additional fetal diagnosis, indicating a higher rate of pregnancy loss compared to cases with isolated CHD (P < 0.0001). CONCLUSIONS: The risk of pregnancy loss is higher in cases with major fetal CHD compared with the general population and varies according to CHD type and presence of additional fetal diagnoses. Improved understanding of the incidence, risk factors and timing of pregnancy loss in CHD cases should inform patient counseling, antenatal surveillance and delivery planning. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Effect of varied dorsiflexion range of motion on landing biomechanics in chronic ankle instability.

BACKGROUND: Limited dorsiflexion range of motion (DFROM) is a risk factor for lateral ankle sprain. However, varied DFROM exists within the chronic ankle instability (CAI) population, and how the variability may influence altered movement patterns during landing is unclear. OBJECTIVE: The purpose of this study was to identify different movement strategies during maximal jump landing/cutting among CAI patients classified by varied DFROM. METHODS: One hundred CAI subjects were classified into 3 subgroups based on their DFROM, measured by the weight-bearing lunge test: a Hypo- (≤40°), Normal- (40-50°), and Hyper-DFROM group (≥50°). Participants completed five trials of maximal jump landing/cutting. Lower extremity joint angles and EMG activation of seven muscles were collected from initial contact to toe-off. Functional analyses of variance were used to evaluate between-group differences for these outcome variables. RESULTS: Hypo-DFROM group (14M, 10F) displayed the reduced ankle dorsiflexion and inversion angles with increased hip flexion angle as a compensatory kinematic chain movement strategy. In addition, motion restrictions of the ankle are associated with altered muscle activation in both distal and proximal muscles during landing/cutting. Normal-DFROM (25M, 30F) and Hyper-DFROM (11M, 10F) groups also have different movement strategies including greater inversion angle and less EMG activation, which could contribute to further ankle injuries. CONCLUSIONS: Our data suggest that limited DFROM negatively affects the ankle joint during demanding movement within the CAI population. These movement patterns in CAI patients with pathomechanical deficits could contribute to further ankle sprains.

Disrupted vision impairs force steadiness and accuracy in chronic ankle instability patients.

The primary purpose of this study was to examine the effect of visual disruption on submaximal force steadiness and accuracy among three groups including chronic ankle instability (CAI) patients, lateral ankle sprain copers, and healthy controls. Twenty patients with CAI, 20 copers, and 20 matched-healthy controls volunteered to participate in the study. Submaximal force steadiness and accuracy for evertors, invertors, and hip abductors (10% and 20% of their maximal voluntary isometric contraction) were measured with an isokinetic dynamometer. All groups performed the tasks with and without stroboscopic glasses. The CAI group showed worse steadiness and accuracy in evertors with visual disruption compared to nonvisual disruption (p < 0.0001 and = 0.02, respectively). Relative to the control group, the CAI group showed worse force steadiness and accuracy in evertors (p < 0.0001, both), worse force accuracy in hip abductors (p = 0.02), and the coper group also showed worse accuracy in evertors (p = 0.02). Individuals with CAI demonstrated impaired force steadiness and accuracy in evertors and hip abductors compared to healthy controls. In addition, they tended to rely more on visual feedback during the force steadiness task than copers and healthy controls.

The effects of visual feedback disruption on postural control with chronic ankle instability.

OBJECTIVES: The purpose of this study was to identify the effects of reduced visual feedback via stroboscopic glasses on dynamic postural control among chronic ankle instability (CAI), lateral ankle sprain (LAS) coper and uninjured control participants. DESIGN: Controlled trial in a laboratory setting. METHODS: Twenty CAI patients, 20 copers, and 20 controls participated in this study. Each participant performed a single-leg hop stabilization test with eyes open (EO) and stroboscopic vision (SV). Two-way ANOVAs (group × condition) were used to examine the differences between group (CAI, coper, and control) and condition (EO and SV). RESULTS: There was a significant group by condition interaction for DPSI scores. CAI patients displayed increased DPSI scores with SV compared to EO (p < 0.01), and CAI patients had increased DPSI scores only with SV when compared with controls. All participants displayed decreased dynamic postural control under the SV condition compared to the EO condition (p < 0.01) regardless of ankle group. CONCLUSIONS: CAI patients rely more on visual feedback during dynamic postural control than copers and controls. However, they may not be as able to compensate for the disrupted visual feedback during a dynamic task. Regardless of ankle injury history, stroboscopic glasses could be cost-effective visual disruption devices during a dynamic balance task.

A Review of the Relationships Between Knee Pain and Movement Neuromechanics.

CONTEXT: Knee injury and disease are common, debilitating, and expensive. Pain is a chief symptom of knee injury and disease and likely contributes to arthrogenic muscle inhibition. Joint pain alters isolated motor function, muscular strength, and movement biomechanics. Because knee pain influences biomechanics, it likely also influences long-term knee joint health. OBJECTIVE: The purpose of this article is 2-fold: (1) review effects of knee pain on lower-extremity muscular activation and corresponding biomechanics and (2) consider potential implications of neuromechanical alterations associated with knee pain for long-term knee joint health. Experimental knee pain is emphasized because it has been used to mimic clinical knee pain and clarify independent effects of knee pain. Three common sources of clinical knee pain are also discussed: patellofemoral pain, anterior cruciate ligament injury and reconstruction, and knee osteoarthritis. DATA SOURCES: The PubMed, Web of Science, and SPORTDiscus databases were searched for articles relating to the purpose of this article. CONCLUSION: Researchers have consistently reported that knee pain alters neuromuscular activation, often in the form of inhibition that likely occurs via voluntary and involuntary neural pathways. The effects of knee pain on quadriceps activation have been studied extensively. Knee pain decreases voluntary and involuntary quadriceps activation and strength and alters the biomechanics of various movement tasks. If allowed to persist, these neuromechanical alterations might change the response of articular cartilage to joint loads during movement and detrimentally affect long-term knee joint health. Physical rehabilitation professionals should consider neuromechanical effects of knee pain when treating knee injury and disease. Resolution of joint pain can likely help to restore normal movement neuromechanics and potentially improve long-term knee joint health and should be a top priority.

Pulse Energy and Pulse Duration Effects in the Ionization and Fragmentation of Iodomethane by Ultraintense Hard X Rays.

The interaction of intense femtosecond x-ray pulses with molecules sensitively depends on the interplay between multiple photoabsorptions, Auger decay, charge rearrangement, and nuclear motion. Here, we report on a combined experimental and theoretical study of the ionization and fragmentation of iodomethane (CH_{3}I) by ultraintense (∼10^{19} W/cm^{2}) x-ray pulses at 8.3 keV, demonstrating how these dynamics depend on the x-ray pulse energy and duration. We show that the timing of multiple ionization steps leading to a particular reaction product and, thus, the product's final kinetic energy, is determined by the pulse duration rather than the pulse energy or intensity. While the overall degree of ionization is mainly defined by the pulse energy, our measurement reveals that the yield of the fragments with the highest charge states is enhanced for short pulse durations, in contrast to earlier observations for atoms and small molecules in the soft x-ray domain. We attribute this effect to a decreased charge transfer efficiency at larger internuclear separations, which are reached during longer pulses.

Mask-induced dermatoses during the COVID-19 pandemic: a questionnaire-based study in 12 Korean hospitals.

BACKGROUND: During the coronavirus disease 2019 (COVID-19) pandemic, various adverse skin reactions to long-term mask wearing have been reported. AIM: To assess the clinical features of mask-induced dermatoses and to recommend prevention and treatment options. METHODS: From April to August 2020, questionnaires including topics such as demographic information, pre-existing skin disorders, reported mask-related symptoms, daily mask-wearing duration and frequency, types of masks used and whether the participant was a healthcare worker, were distributed to patients in 12 hospitals. Dermatologists assessed skin lesions, confirmed diagnosis and recorded treatments. RESULTS: Itchiness was the most frequent symptom, mostly affecting the cheeks. The most common skin disease was new-onset contact dermatitis (33.94%), followed by new-onset acne (16.97%) and worsening of pre-existing acne (16.97%). Daily wearing of masks was significantly (P = 0.02) associated with new-onset contact dermatitis. More than half of patients with pre-existing skin problems experienced disease worsening while wearing masks. Longer duration of wearing (> 6 h/day, P = 0.04) and use of cotton masks (P < 0.001) significantly increased acne flare-up. Healthcare workers had a higher incidence of skin disease. Skin lesions were generally mild and well tolerated with topical treatment. The study had some limitations: the effect of seasonal characteristics and other risk factors were not assessed, and the patients were visiting dermatological clinics and had interest in their skin status, thus, there may have been selection bias. CONCLUSION: Mask-induced/-triggered dermatoses contribute to increase the dermatological burden during the pandemic.

Deep learning for bias correction of MJO prediction.

Producing accurate weather prediction beyond two weeks is an urgent challenge due to its ever-increasing socioeconomic value. The Madden-Julian Oscillation (MJO), a planetary-scale tropical convective system, serves as a primary source of global subseasonal (i.e., targeting three to four weeks) predictability. During the past decades, operational forecasting systems have improved substantially, while the MJO prediction skill has not yet reached its potential predictability, partly due to the systematic errors caused by imperfect numerical models. Here, to improve the MJO prediction skill, we blend the state-of-the-art dynamical forecasts and observations with a Deep Learning bias correction method. With Deep Learning bias correction, multi-model forecast errors in MJO amplitude and phase averaged over four weeks are significantly reduced by about 90% and 77%, respectively. Most models show the greatest improvement for MJO events starting from the Indian Ocean and crossing the Maritime Continent.

Stillbirth and fetal anomalies: secondary analysis of a case-control study.

OBJECTIVE: Approximately 10% of stillbirths are attributed to fetal anomalies, but anomalies are also common in live births. We aimed to assess the relationship between anomalies, by system and stillbirth. DESIGN: Secondary analysis of a prospective, case-control study. SETTING: Multicentre, 59 hospitals in five regional catchment areas in the USA. POPULATION OR SAMPLE: All stillbirths and representative live birth controls. METHODS: Standardised postmortem examinations performed in stillbirths, medical record abstraction for stillbirths and live births. MAIN OUTCOME MEASURES: Incidence of major anomalies, by type, compared between stillbirths and live births with univariable and multivariable analyses using weighted analysis to account for study design and differential consent. RESULTS: Of 465 singleton stillbirths included, 23.4% had one or more major anomalies compared with 4.3% of 1871 live births. Having an anomaly increased the odds of stillbirth; an increasing number of anomalies was more highly associated with stillbirth. Regardless of organ system affected, the presence of an anomaly increased the odds of stillbirth. These relationships remained significant if stillbirths with known genetic abnormalities were excluded. After multivariable analyses, the adjusted odds ratio (aOR) of stillbirth for any anomaly was 4.33 (95% CI 2.80-6.70) and the systems most strongly associated with stillbirth were cystic hygroma (aOR 29.97, 95% CI 5.85-153.57), and thoracic (aOR16.18, 95% CI 4.30-60.94) and craniofacial (aOR 35.25, 95% CI 9.22-134.68) systems. CONCLUSIONS: In pregnancies affected by anomalies, the odds of stillbirth are higher with increasing numbers of anomalies. Anomalies of nearly any organ system increased the odds of stillbirth even when adjusting for gestational age and maternal race. TWEETABLE ABSTRACT: Stillbirth risk increases with anomalies of nearly any organ system and with number of anomalies seen.

Submaximal Force Steadiness and Accuracy in Patients With Chronic Ankle Instability.

CONTEXT: Patients with chronic ankle instability (CAI) have demonstrated sensorimotor impairments. Submaximal force steadiness and accuracy measure sensory, motor, and visual function via a feedback mechanism, which helps researchers and clinicians comprehend the sensorimotor deficits associated with CAI. OBJECTIVE: To determine if participants with CAI experienced deficits in hip and ankle submaximal force steadiness and accuracy compared with healthy control participants. DESIGN: Case-control study. SETTING: Research laboratory. PATIENTS OR OTHER PARTICIPANTS: Twenty-one patients with CAI and 21 uninjured individuals. MAIN OUTCOME MEASURE(S): Maximal voluntary isometric contraction (MVIC) and force steadiness and accuracy (10% and 30% of MVIC) of the ankle evertors and invertors and hip abductors were assessed using the central 10 seconds (20%-87% of the total time) of the 3 trials. RESULTS: Relative to the control group, the CAI group demonstrated less accuracy of the invertors (P < .001). Across all motions, the CAI group showed less steadiness (P < .001) and less accuracy (P < .01) than the control group at 10% of MVIC. For MVIC, the CAI group displayed less force output in hip abduction than the uninjured group (P < .0001). CONCLUSIONS: Patients with CAI were unable to control ongoing fine force (10% and 30% of MVIC) through a feedback mechanism during an active test. These findings suggested that deficits in sensorimotor control predisposed patients with CAI to injury positions because they had difficulty integrating the peripheral information and correcting their movements in relation to visual information.

Insight into the Chemistry of PETN Under Shock Compression Through Ultrafast Broadband Mid-Infrared Absorption Spectroscopy.

Thin films of pentaerythritol tetranitrate (PETN) were shock compressed using the laser driven shock apparatus at Los Alamos National Laboratory (LANL). Two spectroscopic probes were available to this apparatus: visible white light transient absorption spectroscopy (VIS) from 400 to 700 nm and mid-infrared transient absorption spectroscopy (MIR) from 1150 to 3800 cm-1. Important PETN vibrational modes are the symmetric and antisymmetric NO2 stretches at 1280 and 1650 cm-1, respectively, as well as CH stretches at ∼2900 cm-1. Shock strength was varied from approximately 3 to 55 GPa to span from the chemically unreactive regime to the regime in which fast chemical reaction took place on the 250 ps time scale of the measurements. VIS and MIR results suggest irreversible chemistry was induced in PETN at pressures above 30 GPa. At lower shock pressures, the spectroscopy showed minimal changes attributable to pressure induced effects. Under the higher-pressure reactive conditions, the frequency region at the antisymmetric NO2 stretch mode had a significantly increased absorption while the region around the symmetric NO2 stretch did not. No observable increased absorption occurred in the higher frequency regions where CH-, NH-, and OH- bond absorptions would be observed. A broad absorption appeared on the shoulder at the red-edge of the CO2 vibrational band around 2200 cm-1. In addition to the experiments, reactive molecular dynamics were carried out under equivalent shock conditions to correlate the evolution of the infrared spectrum to molecular processes. The simulations show results consistent to experiments up to 30 GPa but suggest that NO and NO2 related features provided the strongest contributions to the shocked infrared changes. Proposed mechanisms for shocked PETN chemistry are analyzed as consistent or inconsistent with the data presented here. Our experimental data suggests C≡O or N2O bond formation, nitrite formation, and absence of significant hydroxyl or amine concentrations in the initial chemistry steps in PETN shocked above 30 GPa.

Neuropathic pain in ankylosing spondylitis: a meta-analysis.

AIM: The aim of this study was to compare demographic characteristics, disease activity, functional status, and quality of life between ankylosing spondylitis (AS) with neuropatic pain (NP) and AS without NP (Non-NP). METHODS: The MEDLINE via PubMed, Cochrane, Scopus, and Embase database, from the earliest available date of indexing through December 20, 2018, were searched for comparative studies evaluating NP in AS patients. Two authors performed the data extraction independently. Any discrepancies were resolved by consensus. RESULTS: Four comparative studies were identified. There was no statistically significant difference in terms of age, body mass index, symptom duration, and inflammatory markers, such as erythrocyte sedimentation rate and C­reactive protein between NP and Non-NP. The sex ratios (F/M) were approximately 1/1 in NP and 1/2 in Non-NP and the proportion of human leukocyte antigen (HLA) B27-positive patients in NP and Non-NP was 65.7% and 83.0%, respectively. NP patients had significantly higher visual analogue scale pain scores, higher Bath Ankylosing Spondylitis Disease Activity Index, higher Bath Ankylosing Spondylitis Functional Index, and lower SF-Item Short Form physical component scores compare to Non-NP patients. CONCLUSION: The current meta-analysis showed that NP patients had significantly higher pain severity, higher disease activity and lower quality of life than Non-NP patients. The sex ratio (F/M) and proportion of HLA-B27 positive patients were different between the two groups. Further well-designed studies are needed to substantiate our results.

A benchtop shock physics laboratory: Ultrafast laser driven shock spectroscopy and interferometry methods.

Common Ti:sapphire chirped pulse amplified laser systems can be readily adapted to be both a generator of adjustable pressure shock waves and a source for multiple probes of the ensuing ultrafast shock dynamics. In this paper, we detail experimental considerations for optimizing the shock generation, interferometric characterization, and spectroscopic probing of shock dynamics with visible and mid-infrared transient absorption. While we have reported results using these techniques elsewhere, here we detail how the spectroscopies are integrated with the shock and interferometry experiment. The interferometric characterization uses information from beams at multiple polarizations and angles of incidence combined with thin film equations and shock dynamics to determine the shock velocity, particle velocity, and shocked refractive index. Visible transient absorption spectroscopy uses a white light supercontinuum in a reflection geometry, synchronized to the shock wave, to time resolve shock-induced changes in visible absorption such as changes to electronic structure or strongly absorbing products and intermediates due to reaction. Mid-infrared transient absorption spectroscopy uses two color filamentation supercontinuum generation combined with a simple thermal imaging microbolometer spectrometer to enable broadband single shot detection of changes in the vibrational spectra. These methods are demonstrated here in the study of shock dynamics at stresses from 5 to 30 GPa in organic materials and from a few GPa to >70 GPa in metals with spatial resolution of a few micrometers and temporal resolution of a few picoseconds. This experiment would be possible to replicate in any ultrafast laser laboratory containing a single bench top commercial chirped pulse amplification laser system.

Altered Movement Biomechanics in Chronic Ankle Instability, Coper, and Control Groups: Energy Absorption and Distribution Implications.

CONTEXT: Patients with chronic ankle instability (CAI) exhibit deficits in neuromuscular control, resulting in altered movement strategies. However, no researchers have examined neuromuscular adaptations to dynamic movement strategies during multiplanar landing and cutting among patients with CAI, individuals who are ankle-sprain copers, and control participants. OBJECTIVE: To investigate lower extremity joint power, stiffness, and ground reaction force (GRF) during a jump-landing and cutting task among CAI, coper, and control groups. DESIGN: Cross-sectional study. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 22 patients with CAI (age = 22.7 ± 2.0 years, height = 174.6 ± 10.4 cm, mass = 73.4 ± 12.1 kg), 22 ankle-sprain copers (age = 22.1 ± 2.1 years, height = 173.8 ± 8.2 cm, mass = 72.6 ± 12.3 kg), and 22 healthy control participants (age = 22.5 ± 3.3 years, height = 172.4 ± 13.3 cm, mass = 72.6 ± 18.7 kg). INTERVENTION(S): Participants performed 5 successful trials of a jump-landing and cutting task. MAIN OUTCOME MEASURE(S): Using motion-capture cameras and a force plate, we collected lower extremity ankle-, knee-, and hip-joint power and stiffness and GRFs during the jump-landing and cutting task. Functional analyses of variance were used to evaluate between-groups differences in these dependent variables throughout the contact phase of the task. RESULTS: Compared with the coper and control groups, the CAI group displayed (1) up to 7% of body weight more posterior and 52% of body weight more vertical GRF during initial landing followed by decreased GRF during the remaining stance and 22% of body weight less medial GRF across most of stance; (2) 8.8 W/kg less eccentric and 3.2 W/kg less concentric ankle power, 6.4 W/kg more eccentric knee and 4.8 W/kg more eccentric hip power during initial landing, and 5.0 W/kg less eccentric knee and 3.9 W/kg less eccentric hip power; and (3) less ankle- and knee-joint stiffness during the landing phase. Concentric power patterns were similar to eccentric power patterns. CONCLUSIONS: The CAI group demonstrated altered neuromechanics, redistributing energy absorption from the distal (ankle) to the proximal (knee and hip) joints, which coincided with decreased ankle and knee stiffness during landing. Our data suggested that although the coper and control groups showed similar landing and cutting strategies, the CAI group used altered strategies to modulate impact forces during the task.

Characterization of Multiple Movement Strategies in Participants With Chronic Ankle Instability.

CONTEXT: Chronic ankle instability (CAI) is characterized by multiple sensorimotor deficits, affecting strength, postural control, motion, and movement. Identifying specific deficits is the key to developing appropriate interventions for this patient population; however, multiple movement strategies within this population may limit the ability to identify specific movement deficits. OBJECTIVE: To identify specific movement strategies in a large sample of participants with CAI and to characterize each strategy relative to a sample of uninjured control participants. DESIGN: Descriptive laboratory study. SETTING: Biomechanics laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 200 individuals with CAI (104 men, 96 women; age = 22.3 ± 2.2 years, height = 174.2 ± 9.5 cm, mass = 72.0 ± 14.0 kg) were selected according to the inclusion criteria established by the International Ankle Consortium and were fit into clusters based on movement strategy. A total of 100 healthy individuals serving as controls (54 men, 46 women; age = 22.2 ± 3.0 years, height = 173.2 ± 9.2 cm, mass = 70.7 ± 13.4 kg) were compared with each cluster. MAIN OUTCOME MEASURE(S): Lower extremity joint biomechanics and ground reaction forces were collected during a maximal vertical jump landing, followed immediately by a side cut. Data were reduced to functional output or curves, kinematic data from the frontal and sagittal planes were reduced to a single representative curve for each plane, and representative curves were clustered using a Bayesian clustering technique. Estimated functions for each dependent variable were compared with estimated functions from the control group to describe each cluster. RESULTS: Six distinct clusters were identified from the frontal-plane and sagittal-plane data. Differences in joint angles, joint moments, and ground reaction forces between clusters and the control group were also identified. CONCLUSIONS: The participants with CAI demonstrated 6 distinct movement strategies, indicating that CAI could be characterized by multiple distinct movement alterations. Clinicians should carefully evaluate patients with CAI for sensorimotor deficits and quality of movement to determine the appropriate interventions for treatment.

Altered Walking Neuromechanics in Patients With Chronic Ankle Instability.

CONTEXT: The literature on gait kinematics and muscle activation in chronic ankle instability (CAI) is limited. A comprehensive evaluation of all relevant gait measures is needed to examine alterations in gait neuromechanics that may contribute to recurrent sprain. OBJECTIVE: To compare walking neuromechanics, including kinematics, muscle activity, and kinetics (ie, ground reaction force [GRF], moment, and power), between participants with and those without CAI by applying a novel statistical analysis to data from a large sample. DESIGN: Controlled laboratory study. SETTING: Biomechanics laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 100 participants with CAI (49 men, 51 women; age = 22.2 ± 2.3 years, height = 174.0 ± 9.7 cm, mass = 70.8 ± 14.4 kg) and 100 individuals without CAI serving as controls (55 men, 45 women; age = 22.5 ± 3.3 years, height = 173.1 ± 13.3 cm, mass = 72.6 ± 18.7 kg). INTERVENTION(S): Participants performed 5 trials of walking (shod) at a self-selected speed over 2 in-ground force plates. MAIN OUTCOME MEASURE(S): Three-dimensional GRFs, lower extremity joint angles, internal joint moments, joint powers, and activation amplitudes of 6 muscles were recorded during stance. RESULTS: Compared with the control group, the CAI group demonstrated (1) increased plantar flexion or decreased dorsiflexion, increased inversion or decreased eversion, decreased knee flexion, decreased knee abduction, and increased hip-flexion angles; (2) increased or decreased inversion, increased plantar flexion, decreased knee extension, decreased knee abduction, and increased hip-extension moments; (3) increased vertical, braking, and propulsive GRFs; (4) increased hip eccentric and concentric power; and (5) altered muscle activation in all 6 lower extremity muscles. CONCLUSIONS: The CAI group demonstrated a hip-dominant strategy by limiting propulsive forces at the ankle while increasing force generation at the hip. The different walking neuromechanics exhibited by the CAI group could represent maladaptive strategies that developed after the initial sprain or an injurious gait pattern that may have predisposed the participants to their initial injuries. Increased joint loading and altered kinematics at the foot and ankle complex during initial stance could affect the long-term health of the ankle articular cartilage.

Moderate hearing loss is related with social frailty in a community-dwelling older adults: The Korean Frailty and Aging Cohort Study (KFACS).

OBJECTIVES: To determine whether hearing loss is associated with social frailty in older adults. METHODS: Cross-sectional analysis of cohort study data. Hearing was measured using of Pure-tone audiometry. Hearing loss was determined based on the average of hearing thresholds at 0.5, 1, and 2 kHz in the ear that had better hearing. Social frailty was defined based on the summation of the following 5 social components (1. Neighborhood meeting attendance 2. Talking to friend(s) sometimes 3.Someone gives you love and affection 4. Living alone 5. Meeting someone every day). Participants who had no correspondence to the components were considered non-social frailty; those with 1-2 components were considered social prefrailty; and those having 3 or more components were considered social frailty. RESULTS: The prevalence of non-social frailty, social prefrailty, social frailty was 27.6%, 60.7% and 11.7% respectively. Of the five questions, two components (Neighborhood meeting attendance and Presence of someone who shows love and affection to the participants) were associated with hearing loss (p < 0.001). Compared to non-social frailty, the odds ratio of social frailty for hearing loss was 2.24 (95% CI 1.48-3.38) after adjusting for age, residential area, economic status, smoking, depressive disorder and MMSE, and 2.17 (95% CI 1.43-3.30) after further adjustments with physical frailty. CONCLUSION: Hearing loss was associated with social frailty even after controlling confounding factors even including physical frailty.

Effect of the Lactobacillus rhamnosus strain GG and tagatose as a synbiotic combination in a dextran sulfate sodium-induced colitis murine model.

Synbiotics, a combination of prebiotics and probiotics, produce synergistic effects to promote gastrointestinal health. Herein, we investigated the synbiotic interaction between the Lactobacillus rhamnosus strain GG (LGG; a probiotic strain) and tagatose (a prebiotic) in a dextran sulfate sodium (DSS)-induced colitis murine model. Initially, body weight, food intake, and clinical features were dramatically decreased after treatment with DSS, and the addition of LGG, tagatose, or both ameliorated these effects. In our pyrosequencing analysis of fecal microbiota, DSS treatment increased the abundance of Proteobacteria and decreased that of Firmicutes. When LGG and tagatose were administered as synbiotics, the gut microbiota composition recovered from the dysbiosis caused by DSS treatment. In particular, the abundance of Bacteroides, Lactobacillus, and Akkermansia was significantly associated with probiotic, prebiotic, and synbiotic treatments. Taken together, our results suggest that LGG and tagatose as synbiotics can alleviate colitis, and synbiotics could be applied as dietary supplements in dairy foods such as yogurt and cheese.