Musculoskeletal Pain, Physical Activity, Muscle Mass, and Mortality in Older Adults: Results from the Korean Longitudinal Study on Health and Aging (KLoSHA).

Background and objectives: Musculoskeletal (MSK) pain significantly impacts physical activity and quality of life in older adults, potentially influencing mortality. This study explored the relationship between MSK pain, physical activity, muscle mass, and mortality among older adults. Material and Methods: We studied 1000 participants in the Korean Longitudinal Study on Health and Aging (KLoSHA), a prospective, population-based cohort study of people aged 65 years or older. Survival status was tracked over a 5-year period. Correlations between low back pain (LBP), knee pain, regular exercise, appendicular skeletal muscle mass (ASM), and other variables were analyzed. Logistic regression analyses were used to identify independent risk factors for mortality. Results: Of the total participants, 829 (82.9%) survived over a 5-year period. Survivors tended to be younger, had a higher BMI, and were more active in regular exercise. In contrast, non-survivors exhibited a higher prevalence of both LBP and knee pain, along with increased instances of multiple MSK pains. Lower ASM correlated moderately with LBP and knee pain, whereas higher ASM was associated with regular exercise. There was a moderate correlation between LBP and knee pain, both of which were associated with a lack of regular exercise. Age, sex, ASM, and regular exercise were significant predictors, even though MSK pain itself did not directly predict all-cause mortality. Conclusions: This study demonstrated the independent association between ASM, regular exercise, and mortality. Although MSK pain did not directly correlate with all-cause mortality, the non-survivor group had higher levels of both single and multiple MSK pains. Recognizing the interplay of MSK pain, physical activity, and muscle mass for older adults, the research underscores the need for holistic strategies to enhance health outcomes in older individuals with MSK pain.

Social connections and risk of incident mild cognitive impairment, dementia, and mortality in 13 longitudinal cohort studies of ageing.

INTRODUCTION: Previous meta-analyses have linked social connections and mild cognitive impairment, dementia, and mortality. However, these used aggregate data from North America and Europe and examined a limited number of social connection markers. METHODS: We used individual participant data (N = 39271, Mage  = 70.67 (40-102), 58.86% female, Meducation  = 8.43 years, Mfollow-up  = 3.22 years) from 13 longitudinal ageing studies. A two-stage meta-analysis of Cox regression models examined the association between social connection markers with our primary outcomes. RESULTS: We found associations between good social connections structure and quality and lower risk of incident mild cognitive impairment (MCI); between social structure and function and lower risk of incident dementia and mortality. Only in Asian cohorts, being married/in a relationship was associated with reduced risk of dementia, and having a confidante was associated with reduced risk of dementia and mortality. DISCUSSION: Different aspects of social connections - structure, function, and quality - are associated with benefits for healthy aging internationally. HIGHLIGHTS: Social connection structure (being married/in a relationship, weekly community group engagement, weekly family/friend interactions) and quality (never lonely) were associated with lower risk of incident MCI. Social connection structure (monthly/weekly friend/family interactions) and function (having a confidante) were associated with lower risk of incident dementia. Social connection structure (living with others, yearly/monthly/weekly community group engagement) and function (having a confidante) were associated with lower risk of mortality. Evidence from 13 longitudinal cohort studies of ageing indicates that social connections are important targets for reducing risk of incident MCI, incident dementia, and mortality. Only in Asian cohorts, being married/in a relationship was associated with reduced risk of dementia, and having a confidante was associated with reduced risk of dementia and mortality.

Optimization of signal amplification by reversible exchange for polarization of tridentate chelating bis[(2-pyridyl)alkyl]amine.

Signal amplification by reversible exchange (SABRE) is an effective NMR hyperpolarization technique for signal enhancement using para-hydrogen on iridium catalysts. To date, monodentate chelating nitrogen analogs have been predominantly used as substrates for SABRE because of the limited chelating sites of the Ir-catalyst with different molecular orientations. Herein, for the first time, the use of a tridentate chelating ligand (BPEA) containing pyridine moieties and a secondary amine as a SABRE substrate is demonstrated. For the optimization of the tridentate chelating ligand, alkyl chain lengths were varied with the optimization of the external magnetic field and concentrations of three different ligands. Because many chemically multidentate complexes present in nature have scarcely been studied as SABRE substrates, this optimized tridentate chelating ligand structure with the SABRE catalyst and its polarization transfer from para-hydrogen will broaden the scope of hyperpolarizable substrates and help in the investigation of chelating structures for future applications.

Organic Reaction Monitoring of a Glycine Derivative Using Signal Amplification by Reversible Exchange-Hyperpolarized Benchtop Nuclear Magnetic Resonance Spectroscopy.

Currently, signal amplification by reversible exchange (SABRE) using para-hydrogen is an attractive method of hyperpolarization for overcoming the sensitivity problems of nuclear magnetic resonance (NMR) spectroscopy. Additionally, SABRE, using the spin order of para-hydrogen, can be applied in reaction monitoring processes for organic chemistry reactions where a small amount of reactant exists. The organic reaction monitoring system created by integrating SABRE and benchtop NMR is the ideal combination for monitoring a reaction and identifying the small amounts of materials in the middle of the reaction. We used a laboratory-built setup, prepared materials by synthesis, and showed that the products obtained by esterification of glycine were also active in SABRE. The products, which were synthesized esterified glycine with nicotinoyl chloride hydrochloride, were observed with a reaction monitoring system. The maximum SABRE enhancement among them (approximately 147-fold) validated the use of this method. This study is the first example of the monitoring of this organic reaction by SABRE and benchtop NMR. It will open new possibilities for applying this system to many other organic reactions and also provide more fruitful future applications such as drug discovery and mechanism study.

Molecular Encapsulation of Trimeric Chromium Carboxylate Clusters in Metal-Organic Frameworks and Propylene Sorption.

Oxo-bridged trimeric chromium acetate clusters [Cr3 O(OOCCH3 )6 (H2 O)3 ]NO3 have been encapsulated for the first time in the mesoporous cages of the chromium terephthalate MIL-101(Cr). The isolated clusters in MIL-101(Cr) have increased affinity towards propylene compared to propane, due to generation of a new kind of pocket-based propylene-binding site, as supported by DFT calculations.

Crossly charged microfluidic device for spontaneous filtration without an external power supply.

Spontaneous filtration without a power supply was investigated using highly charged precursor mixtures instead of recognized microfluidic desalination techniques. The proposed filtration method consisted of a main channel (depth: 1 mm) and shallow channels (depth: 400 µm) in which the precursor mixture was injected. The filtration performance of the proposed device was evaluated by injecting a fluorescent dye that moved toward the centerline of the main channel. The respective rejection rates of CaCl2, NaCl, CaSO4, and Na2SO4 were 3.16%, 30.13%, 43.74%, and 36.32%, respectively. This trend can be explained by the mechanism of Donnan exclusion theory. The focusing of charged species toward the centerline of the main channel was caused by highly charged surfaces. The proposed filtration method exhibited a migration of charged microparticles toward a certain direction. This particle migration behavior was consistent with the simulation data. These results suggested that the proposed filtration method had strong potential for desalinating brackish water or salty surface water without an external power supply.

Super-Resolution for Improving EEG Spatial Resolution using Deep Convolutional Neural Network-Feasibility Study.

Electroencephalography (EEG) has relatively poor spatial resolution and may yield incorrect brain dynamics and distort topography; thus, high-density EEG systems are necessary for better analysis. Conventional methods have been proposed to solve these problems, however, they depend on parameters or brain models that are not simple to address. Therefore, new approaches are necessary to enhance EEG spatial resolution while maintaining its data properties. In this work, we investigated the super-resolution (SR) technique using deep convolutional neural networks (CNN) with simulated EEG data with white Gaussian and real brain noises, and experimental EEG data obtained during an auditory evoked potential task. SR EEG simulated data with white Gaussian noise or brain noise demonstrated a lower mean squared error and higher correlations with sensor information, and detected sources even more clearly than did low resolution (LR) EEG. In addition, experimental SR data also demonstrated far smaller errors for N1 and P2 components, and yielded reasonable localized sources, while LR data did not. We verified our proposed approach's feasibility and efficacy, and conclude that it may be possible to explore various brain dynamics even with a small number of sensors.

Magnetoencephalographic study of event-related fields and cortical oscillatory changes during cutaneous warmth processing.

Thermoreception is an important cutaneous sense, which plays a role in the maintenance of our body temperature and in the detection of potential noxious heat stimulation. In this study, we investigated event-related fields (ERFs) and neural oscillatory activities, which were modulated by warmth stimulation. We developed a warmth stimulator that could elicit a warmth sensation, without pain or tactile sensation, by using a deep-penetrating 980-nm diode laser. The index finger of each participant (n = 24) was irradiated with the laser warmth stimulus, and the cortical responses were measured using magnetoencephalography (MEG). The ERFs and oscillatory responses had late latencies (∼1.3 s and 1.0-1.5 s for ERFs and oscillatory responses, respectively), which could be explained by a slow conduction velocity of warmth-specific C-fibers. Cortical sources of warmth-related ERFs were seen in the bilateral primary and secondary somatosensory cortices (SI and SII), posterior part of the anterior cingulate cortex (pACC), ipsilateral primary motor, and premotor cortex. Thus, we suggested that SI, SII, and pACC play a role in processing the warmth sensation. Time-frequency analysis demonstrated the suppression of the alpha (8-13 Hz) and beta (18-23 Hz) band power in the bilateral sensorimotor cortex. We proposed that the suppressions in alpha and beta band power are involved in the automatic response to the input of warmth stimulation and sensorimotor interactions. The delta band power (1-4 Hz) increased in the frontal, temporal, and cingulate cortices. The power changes in delta band might be related with the attentional processes during the warmth stimulation.

Interbrain phase synchronization during turn-taking verbal interaction-a hyperscanning study using simultaneous EEG/MEG.

Recently, neurophysiological findings about social interaction have been investigated widely, and hardware has been developed that can measure multiple subjects' brain activities simultaneously. These hyperscanning studies have enabled us to discover new and important evidences of interbrain interactions. Yet, very little is known about verbal interaction without any visual input. Therefore, we conducted a new hyperscanning study based on verbal, interbrain turn-taking interaction using simultaneous EEG/MEG, which measures rapidly changing brain activities. To establish turn-taking verbal interactions between a pair of subjects, we set up two EEG/MEG systems (19 and 146 channels of EEG and MEG, respectively) located ∼100 miles apart. Subjects engaged in verbal communication via condenser microphones and magnetic-compatible earphones, and a network time protocol synchronized the two systems. Ten subjects participated in this experiment and performed verbal interaction and noninteraction tasks separately. We found significant oscillations in EEG alpha and MEG alpha/gamma bands in several brain regions for all subjects. Furthermore, we estimated phase synchronization between two brains using the weighted phase lag index and found statistically significant synchronization in EEG and MEG data. Our novel paradigm and neurophysiological findings may foster a basic understanding of the functional mechanisms involved in human social interactions. Hum Brain Mapp 39:171-188, 2018. © 2017 Wiley Periodicals, Inc.

Pressure-driven spontaneous ion concentration polarization using an ion-selective membrane.

In this study, the spontaneous ion concentration polarization phenomenon induced by pressure via a cation-selective membrane was theoretically and experimentally investigated. Unlike conventional electrokinetic ion concentration polarization, which uses electric current as a driving flux of cations through the membrane, advection caused by pressure is used as a transmembrane driving flux of cations to spontaneously and stably form an ion depletion zone in the present ion concentration polarization technique. The ion depletion zone produced in a simple experimental setup was used to filter electrolyte and preconcentrate ions and microparticles. Different from the general assumption of the negligible thickness of the electric double layer in microchannels, the low concentration in the ion depletion zone considerably increased the length of the electric double layer. This enhanced the formation of the ion depletion zone. The present results can improve the understanding on ion transport in the ion concentration polarization system and can be utilized to develop a portable water desalination device for rural/remote areas and for preconcentrating biomolecules.

Cognitive responses and cortical oscillatory processing at various stereoscopic depths - a simultaneous EEG/MEG study.

Due to the recent explosion in various forms of 3D content, the evaluation of such content from a neuroscience perspective is quite interesting. However, existing investigations of cortical oscillatory responses in stereoscopic depth perception are quite rare. Therefore, we investigated spatiotemporal and spatio-temporo-spectral features at four different stereoscopic depths within the comfort zone. We adopted a simultaneous EEG/MEG acquisition technique to collect the oscillatory responses of eight participants. We defined subject-specific retinal disparities and designed a single trial-based stereoscopic viewing experimental paradigm. In the group analysis, we observed that, as the depth increased from Level 1 to Level 3, there was a time-locked increase in the N200 component in MEG and the P300 component in EEG in the occipital and parietal areas, respectively. In addition, initial alpha and beta event-related desynchronizations (ERD) were observed at approximately 500 to 1000 msec, while theta, alpha, and beta event-related synchronizations (ERS) appeared at approximately 1000 to 2000 ms. Interestingly, there was a saturation point in the increase in cognitive responses, including N200, P300, and alpha ERD, even when the depth increased only within the comfort zone. Meanwhile, the magnitude of low beta ERD decreased in the dorsal pathway as depth increased. From these findings, we concluded that cognitive responses are likely to become saturated in the visual comfort zone, while perceptual load may increase with depth.

Cortical Responses and Shape Complexity of Stereoscopic Image - A Simultaneous EEG/MEG Study.

BACKGROUND/AIMS: In exploring human factors, stereoscopic 3D images have been used to investigate the neural responses associated with excessive depth, texture complexity, and other factors. However, the cortical oscillation associated with the complexity of stereoscopic images has been studied rarely. Here, we demonstrated that the oscillatory responses to three differently shaped 3D images (circle, star, and bat) increase as the complexity of the image increases. METHODS: We recorded simultaneous EEG/MEG for three different stimuli. Spatio-temporal and spatio-spectro-temporal features were investigated by non-parametric permutation test. RESULTS: The results showed that N300 and alpha inhibition increased in the ventral area as the shape complexity of the stereoscopic image increased. CONCLUSION: It seems that the relative disparity in complex stereoscopic images may increase cognitive processing (N300) and cortical load (alpha inhibition) in the ventral area.

The Internal Structure of Macroporous Membranes and Transport of Surface-Modified Nanoparticles.

Understanding the morphological structure of membranes is essential to improve performance of membrane-based applications. In this paper, macroporous membranes were investigated and two methods introduced as an alternative for characterization of stereo-structure of the membranes. We combined the use of synchrotron X-ray nanotomography and small-angle X-ray scattering to examine the internal structure of cellulose acetate membranes with studies of the capture of surface-modified gold nanoparticles within these membranes. Finally, the morphological structures of macroporous membranes were visualized and their relationships with penetration tendency of surface-modified gold nanoparticles were explained.

Multi-channel atomic magnetometer for magnetoencephalography: a configuration study.

Atomic magnetometers are emerging as an alternative to SQUID magnetometers for detection of biological magnetic fields. They have been used to measure both the magnetocardiography (MCG) and magnetoencephalography (MEG) signals. One of the virtues of the atomic magnetometers is their ability to operate as a multi-channel detector while using many common elements. Here we study two configurations of such a multi-channel atomic magnetometer optimized for MEG detection. We describe measurements of auditory evoked fields (AEF) from a human brain as well as localization of dipolar phantoms and auditory evoked fields. A clear N100m peak in AEF was observed with a signal-to-noise ratio of higher than 10 after averaging of 250 stimuli. Currently the intrinsic magnetic noise level is 4fTHz(-1/2) at 10Hz. We compare the performance of the two systems in regards to current source localization and discuss future development of atomic MEG systems.

Toward a brain functional connectivity mapping modality by simultaneous imaging of coherent brainwaves.

Matching the proton-magnetic-resonance frequency to the frequency of a periodic neural oscillation (e.g., alpha or gamma band waves) by magnetic resonance imaging techniques, enables direct visualization of brain functional connectivity. Functional connectivity has been studied by analyzing the correlation between coherent neural oscillations in different areas of the brain. In electro- or magneto-encephalography, coherent source reconstruction in a source-space is very tricky due to power leaking from the correlation among the sources. For this reason, most studies have been limited to sensor-space analyses, which give doubtful results because of volume current mixing. The direct visualization of coherent brain oscillations can circumvent this problem. The feasibility of this idea was demonstrated by conducting phantom experiments with a SQUID-based, micro-Tesla NMR/MRI system. We introduce an experimental trick, an effective step-up of the measurement B-field in a pulse sequence, to decouple the magnetic resonance signal from the strong magneto-encephalographic signal at the same frequency.

Flat-response spin-exchange relaxation free atomic magnetometer under negative feedback.

We demonstrate that the use of negative feedback extends the detection bandwidth of an atomic magnetometer in a spin-exchange relaxation free (SERF) regime. A flat-frequency response from zero to 190 Hz was achieved, which is nearly a three-fold enhancement while maintaining sensitivity, 3 fT/Hz1/2 at 100 Hz. With the extension of the bandwidth, the linear correlation between measured signals and a magne-tocardiographic field synthesized for comparison was increased from 0.21 to 0.74. This result supports the feasibility of measuring weak biomagnetic signals containing multiple frequency components using a SERF atomic magnetometer under negative feedback.

Promoting alkali and alkaline-earth metals on MgO for enhancing CO2 capture by first-principles calculations.

Developing next-generation solid sorbents to improve the economy of pre- and post-combustion carbon capture processes has been challenging for many researchers. Magnesium oxide (MgO) is a promising sorbent because of its moderate sorption-desorption temperature and low heat of sorption. However, its low sorption capacity and thermal instability need to be improved. Various metal-promoted MgO sorbents have been experimentally developed to enhance the CO2 sorption capacities. Nevertheless, rigorous computational studies to screen an optimal metal promoter have been limited to date. We conducted first-principles calculations to select metal promoters of MgO sorbents. Five alkali (Li-, Na-, K-, Rb-, and Cs-) and 4 alkaline earth metals (Be-, Ca-, Sr-, and Ba-) were chosen as a set of promoters. Compared with the CO2 adsorption energy on pure MgO, the adsorption energy on the metal-promoted MgO sorbents is higher, except for the Na-promoter, which indicates that metal promotion on MgO is an efficient approach to enhance the sorption capacities. Based on the stabilized binding of promoters on the MgO surface and the regenerability of sorbents, Li, Ca, and Sr were identified as adequate promoters among the 9 metals on the basis of PW91/GGA augmented with DFT+D2. The adsorption energies of CO2 on metal-promoted MgO sorbents for Li, Ca, and Sr atoms are -1.13, -1.68, and -1.48 eV, respectively.

Differences in sarcopenia status and mortality according to physical activity: results from the Korean Longitudinal Study on Health and Aging (KLoSHA).

PURPOSE: There is increasing evidence that promoting physical activity can prevent sarcopenia. However, physical activity (PA) decreases with age, and the impact of PA intensity on health is unclear. This study investigated the relationship between the level of PA and sarcopenia, and the association between PA levels and mortality in patients with and without sarcopenia. METHODS: Data were derived from the Korean Longitudinal Study on Health and Aging. PA was classified as sedentary behavior, light PA, or moderate-to-vigorous PA. Each PA level was subdivided based on the median time spent engaged in that activity, yielding eight PA profiles. Logistic regression and Cox proportional hazard models were used to investigate the association between PA level and sarcopenia, and between PA profiles and mortality. RESULTS: This study included 620 participants (50.2% women; mean age 75.7 ± 7.5 years), of whom 130 (21.0%) participants were identified sarcopenia. During follow-up (mean 10.9 ± 4.1 years), 264 (42.6%) participants died. Overall, sarcopenic participants were less physically active than non-sarcopenic participants. After multivariate adjustment, more sedentary behavior and less moderate-to-vigorous PA were associated with sarcopenia and all related variables, except muscle mass. Compared with the reference, non-sarcopenic participants with lower sedentary behavior and concomitantly higher moderate-to-vigorous PA had significantly lower hazard ratios for mortality, while higher light PA reduced mortality in sarcopenic participants regardless of time spent engaged in sedentary behavior or moderate-to-vigorous PA. CONCLUSIONS: PA, especially sedentary behavior and moderate-to-vigorous PA, was associated with sarcopenia and related variables, but the level of PA that prevented death differed according to sarcopenia status. Our findings may help determine the optimal intensity and amount of PA.

Rhinitis in a community elderly population: relationships with age, atopy, and asthma.

BACKGROUND: Rhinitis is one of the most frequent medical conditions. However, there is sparse epidemiologic evidence for rhinitis in the elderly population. OBJECTIVE: To investigate the prevalence of rhinitis in elderly adults and its relations to asthma and other comorbidities. METHODS: A cross-sectional analysis was performed using the baseline dataset of the Korean Longitudinal Study on Health and Aging, a community-based elderly population cohort in Korea (≥65 years old). Structured questionnaires were used to define rhinitis, asthma, and comorbidity, and allergen skin prick tests were used to define atopy. Health-related quality of life was assessed by short-form 36 questionnaires. RESULTS: In total, 982 elderly adults (98.2%) were included in the present study. The prevalence of rhinitis was 25.6% and did not decrease until 90 years of age. The prevalence of atopy was 17.2% (18.8% in participants with rhinitis), and atopy did not show a significant association with rhinitis. In multivariate logistic regression analyses, relations between asthma and rhinitis were significant. Among comorbid conditions, none were significantly associated with rhinitis. In the short-form 36 questionnaire analyses, rhinitis was independently related to a decrease in the physical aspects of quality of life. CONCLUSION: The present study found a high prevalence of nonallergic rhinitis in elderly participants, which was significantly related to asthma and quality of life.

'Is tinnitus accompanied by hemifacial spasm in normal-hearing patients also a type of hyperactive neurovascular compression syndrome? : A magnetoencephalography study.

BACKGROUND: Traditionally, tinnitus accompanied by hemifacial spasm has been considered a type of hyperactive neurovascular compression syndrome that is similar to hemifacial spasm alone because of the anatomically close relationship between the facial nerve and cochlear nerve as well as the hyperactive clinical nature. METHODS: Participants were 29 subjects who presented with hemifacial spasm and neuroradiological evidence of vascular compression of the cranial (facial/cochlear) nerve. We used magnetoencephalography (MEG) to estimate the activity of the cochlear nerve in patients with and without tinnitus on the ipsilateral side. We compared the difference in the latency and the ratio of the equivalent current dipole (ECD) strength between the ipsilateral and contralateral sides of the spasm and tinnitus. RESULTS: Cochlear nerve activity in patients with tinnitus was increased with a shorter latency (p = 0.016) and stronger ECD strength (p = 0.028) compared with patients without tinnitus. CONCLUSION: The MEG results from normal-hearing patients who had tinnitus accompanied by hemifacial spasm suggest that the hyperactivity of the auditory central nervous system may be a crucial pathophysiological factor in the generation of tinnitus in these patients. The neurovascular compression that causes sensory input from the pathologic facial nerve activity may contribute to this hyperactivity of the central auditory nervous system.