MRI Compatible Lumbopelvic Movement Measurement System to Validate and Capture Task Performance During Neuroimaging.

Research suggests that structural and functional changes within the brain are associated with chronic low back pain, and these cortical alterations might contribute to impaired sensorimotor control of the trunk and hips in this population. However, linking sensorimotor brain changes with altered movement of the trunk and hips during task-based neuroimaging presents significant challenges. An MRI-safe pressure measurement system was developed to ensure proper task completion during neuroimaging by capturing movement patterns of the trunk (sensors under the lower back) and hips (sensors embedded in the foam roll under the knees). Pressure changes were measured outside of the scanner by digital differential pressure sensors to capture time-series data and analog pressure gauges for real-time determination of task performance occurring within an MRI bore during brain imaging. This study examined the concurrent validity of air pressure changes between the digital and analog sensors. The digital and analog data were compared in 23 participants during the performance of modified bilateral and unilateral right and left hip bridges. Spearman's correlations were calculated for each sensor during the three bridging tasks and showed high positive correlations, indicating that over 87% of pressure change from the analog gauge can be explained by the pressure from the digital sensor. Bland-Altman plots showed no bias and mean differences were under three mmHg. This pressure system improves the rigor of future studies by validating the digital data from the system and increasing the capabilities of capturing lumbopelvic task performance occurring inside the scanner bore.

Multivariate Machine Learning Models of Nanoscale Porosity from Ultrafast NMR Relaxometry.

Nanoporous materials are of great interest in many applications, such as catalysis, separation, and energy storage. The performance of these materials is closely related to their pore sizes, which are inefficient to determine through the conventional measurement of gas adsorption isotherms. Nuclear magnetic resonance (NMR) relaxometry has emerged as a technique highly sensitive to porosity in such materials. Nonetheless, streamlined methods to estimate pore size from NMR relaxometry remain elusive. Previous attempts have been hindered by inverting a time domain signal to relaxation rate distribution, and dealing with resulting parameters that vary in number, location, and magnitude. Here we invoke well-established machine learning techniques to directly correlate time domain signals to BET surface areas for a set of metal-organic frameworks (MOFs) imbibed with solvent at varied concentrations. We employ this series of MOFs to establish a correlation between NMR signal and surface area via partial least squares (PLS), following screening with principal component analysis, and apply the PLS model to predict surface area of various nanoporous materials. This approach offers a high-throughput, non-destructive way to assess porosity in c.a. one minute. We anticipate this work will contribute to the development of new materials with optimized pore sizes for various applications.

Test-retest reliability and construct validity of trunk extensor muscle force modulation accuracy.

Low back pain is associated with changes in trunk muscle structure and function and motor control impairments. Voluntary force modulation (FM) of trunk muscles is a unique and under-investigated motor control characteristic. One of the reasons for this paucity of evidence is the lack of exploration and publication on the reliability and validity of trunk FM protocols. The purpose of this study was to determine the within- and between-day test-retest reliability and construct validity for trunk extensor muscle FM. Twenty-nine healthy participants were tested under three FM conditions with different modulation rates. Testing was performed on a custom-built apparatus designed for trunk isometric force testing. FM accuracy relative to a fluctuating target force (20-50%MVF) was quantified using the root mean square error of the participant's generated force relative to the target force. Reliability and precision of measurement were assessed using the Intraclass Correlation Coefficient (ICC), standard error of measurement (SEM), minimal detectable difference (MDD95), and Bland-Altman plots. In a subset of participants, we collected surface electromyography of trunk and hip muscles. We used non-negative matrix factorization (NNMF) to identify the underlying motor control strategies. Within- and between-day test-retest reliability was excellent for FM accuracy across the three conditions (ICC range: 0.865 to 0.979). SEM values ranged 0.9-1.8 Newtons(N) and MDD95 ranged from 2.4-4.9N. Conditions with faster rates of FM had higher ICCs. NNMF analysis revealed two muscle synergies that were consistent across participants and conditions. These synergies demonstrate that the muscles primarily involved in this FM task were indeed the trunk extensor muscles. This protocol can consistently measure FM accuracy within and between testing sessions. Trunk extensor FM, as measured by this protocol, is not specific to any trunk muscle group but is the result of modulation by all the trunk extensor muscles.

Characterization of Chemisorbed Species and Active Adsorption Sites in Mg-Al Mixed Metal Oxides for High-Temperature CO2 Capture.

Mg-Al mixed metal oxides (MMOs), derived from the decomposition of layered double hydroxides (LDHs), have been purposed as adsorbents for CO2 capture of industrial plant emissions. To aid in the design and optimization of these materials for CO2 capture at 200 °C, we have used a combination of solid-state nuclear magnetic resonance (ssNMR) and density functional theory (DFT) to characterize the CO2 gas sorption products and determine the various sorption sites in Mg-Al MMOs. A comparison of the DFT cluster calculations with the observed 13C chemical shifts of the chemisorbed products indicates that mono- and bidentate carbonates are formed at the Mg-O sites with adjacent Al substitution of an Mg atom, while the bicarbonates are formed at Mg-OH sites without adjacent Al substitution. Quantitative 13C NMR shows an increase in the relative amount of strongly basic sites, where the monodentate carbonate product is formed, with increasing Al/Mg molar ratios in the MMOs. This detailed understanding of the various basic Mg-O sites presented in MMOs and the formation of the carbonate, bidentate carbonate, and bicarbonate chemisorbed species yields new insights into the mechanism of CO2 adsorption at 200 °C, which can further aid in the design and capture capacity optimization of the materials.

Synthesis of Mg Alkoxide Nanowires from Mg Alkoxide Nanoparticles upon Ligand Exchange.

We report on a new synthesis pathway for Mg n-propoxide nanowires (NWs) from Mg ethoxide nanoparticles using a simple alkoxy ligand exchange reaction followed by condensation polymerization in n-propanol. In order to uncover the morphology-structure correlation in the metal alkoxide family, we employed a powerful range of state-of-the-art characterization techniques. The morphology transformation from nanoparticles to nanowires was demonstrated by time-lapse SEM micrographs. Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (such as 1H NMR and solid-state 13C cross-polarization (CP)-MAS NMR) illustrated the replacement of ethyl by n-propyl and metal alkoxide condensation polymerization. We identified chemical formulas of the products also using NMR spectroscopy. The crystal structure simulation of Mg ethoxide particles and Mg n-propoxide NWs provided insights on how the ligand exchange and the associated increase in the fraction of OH groups greatly enhanced Mg alkoxide bonding and enabled a higher degree of coordination polymerization to facilitate the formation and growth of the Mg n-propoxide NWs. The discovered synthesis method could be extended for the fabrication of other metal alkoxide (nano) structures with various morphologies.

The Association Between Polyvictimization in Childhood and Intimate Partner Violence and Child Abuse in Adulthood.

The main purpose of this study was to examine the association of family polyvictimization in childhood with the victimization or perpetration of spousal abuse and the perpetration of child abuse in adulthood. While associations between maltreatment in childhood and subsequent perpetration or victimization in adulthood are well documented, their association with polyvictimization in childhood (i.e., experiencing multiple types of victimization) has received less attention. This research aims to empirically investigate 1) whether early experiences of family polyvictimization are predictive of subsequent experience or spousal abuse or perpetration of child abuse and 2) whether there are gender differences in those associations. Through conducting Chi-square analysis and logistic regression analysis with South Korea's National Domestic Violence Survey 2019, the study found significant empirical evidence that polyvictimization is predictive of perpetration or experience of spousal abuse and perpetration of child abuse. Particularly, adults who experienced polyvictimization in childhood were more likely to perpetrate child abuse regardless of the type of abuse (p < .001). Polyvictimization in childhood was also significantly associated with perpetration and victimization of spousal abuse (p < .001). In regard to gender differences, this study found that males were more likely to be polyvictimized by family in childhood (15.11%) than females (10.23%), and polyvictimization was found to increase the likelihood of females being revictimized in adulthood. More attention should be paid to victimization by multiple types of violence within the family and its influence on intergenerational transmission of violence.

Bispecific Antibody Designed for Targeted NK Cell Activation and Functional Assessment for Biomedical Applications.

Natural killer (NK) cells serve as key innate effectors and their activity has been considered a prognostic biomarker in diverse human diseases. Currently, NK cell functional assays have several problems primarily related to adequate preparation, labeling, or treatment of target cells, which are cumbersome and often hamper consistent sensitivity for NK cells. Here, bispecific antibodies (BsAb's) targeting NKG2D and 2B4 receptors, whose combination mounts selective cytotoxicity and IFN-γ production of NK cells, are developed as acellular, consistent, and easy-to-use strategies for assessing NK cell functions. These NK cell activator BsAb's (NKABs) are constructed in symmetric dual bivalent formats with different interdomain spacings [immunoglobulin G (IgG)-single-chain variable fragment (scFv) and dual-variable domain (DVD)-Ig] and kappa constant (Cκ)-scFv format linking two scFv's with a Cκ domain. These NKABs are specific and superior to a combination of monospecific antibodies for NK cell activation. NKAB elicits both direct cytotoxicity and IFN-γ production via integration of NKG2D and 2B4 signals. Moreover, stimulation with NKAB IgG-scFv and Cκ-scFv reveals defective NK cell functions in X-linked lymphoproliferative disease involving 2B4 dysfunction in NK cells and multiple myeloma in peripheral blood mononuclear cells and whole blood, respectively. Hence, this work provides a proof of concept that NKAB facilitates the reliable and comprehensive measurement of NK cell function in clinical settings for diagnostic and prognostic purposes.

Electrolyte melt infiltration for scalable manufacturing of inorganic all-solid-state lithium-ion batteries.

All-solid-state lithium (Li) metal and lithium-ion batteries (ASSLBs) with inorganic solid-state electrolytes offer improved safety for electric vehicles and other applications. However, current inorganic ASSLB manufacturing technology suffers from high cost, excessive amounts of solid-state electrolyte and conductive additives, and low attainable volumetric energy density. Such a fabrication method involves separate fabrications of sintered ceramic solid-state electrolyte membranes and ASSLB electrodes, which are then carefully stacked and sintered together in a precisely controlled environment. Here we report a disruptive manufacturing technology that offers reduced manufacturing costs and improved volumetric energy density in all solid cells. Our approach mimics the low-cost fabrication of commercial Li-ion cells with liquid electrolytes, except that we utilize solid-state electrolytes with low melting points that are infiltrated into dense, thermally stable electrodes at moderately elevated temperatures (~300 °C or below) in a liquid state, and which then solidify during cooling. Nearly the same commercial equipment could be used for electrode and cell manufacturing, which substantially reduces a barrier for industry adoption. This energy-efficient method was used to fabricate inorganic ASSLBs with LiNi0.33Mn0.33Co0.33O2 cathodes and both Li4Ti5O12 and graphite anodes. The promising performance characteristics of such cells open new opportunities for the accelerated adoption of ASSLBs for safer electric transportation.

Child Abuse Victimization, Depression, and Substance Use Among Homeless Women: Application of General Strain Theory.

The main purpose of this study was to investigate the association between child abuse and substance use among homeless women based on a framework of General Strain Theory, which emphasizes the strong relationship between deviant behaviors and personally experienced strain. In this study, as the strain associated with substance use, child abuse experience in the past was assessed. This research tested three hypotheses about (a) the association between physical and sexual abuse during childhood and substance use (heavy drinking, marijuana use, and crack cocaine use), (b) the mediating effect of depressive symptoms, and (c) the moderating effect of positive social supports on the relationship between abuse during childhood and substance use with a survey and interview data of a randomly selected sample of 445 homeless women in a temporary shelter setting in Los Angeles County between June 2007 and March 2008. Although the results indicated that abuse during childhood was not significantly associated with any form of substance use, the results of multivariate analyses indicated that depressive symptoms fully mediated the four relationships (p < .01; physical abuse and heavy drinking, physical abuse and crack cocaine use, sexual abuse and heavy drinking, and sexual abuse and crack cocaine use). The results of this study also indicated that positive social supports significantly moderate the effect of physical (p < .01) and sexual (p < .05) abuse experience on heavy drinking, which implies that positive social supports would be significant to reduce substance use among homeless women who had a history of physical and sexual abuse during childhood.

The Comparative Macro-Level Ageism Index: An International Comparison.

Ageism, socially constructed discrimination against seniors, influences the quality of life of older adults. This study aimed to compare ageism in 15 Organization for Economic Cooperation and Development (OECD) countries using the scientifically developed Comparative Macro-Level Ageism Index (CMAI). We developed the CMAI by reviewing previous index research on the life of older people and conducting expert interviews using a Delphi method. We identified five domains, economic status, health, employment, environment, and social participation, and 17 indicators of ageism. Standardized ageism scores were compared across 15 OECD countries. The results indicated that the overall ageism score was highest in Turkey and lowest in Japan. Turkey was the most likely while South Korea was the least likely to practice age discrimination in the workplace. Yet, South Korea had the highest score for discriminating against seniors based on economic status while Spain had the lowest score in this domain. Japan had favorable conditions for economic status, health status, and social participation for older adults. Implications of this study and suggestions for further studies on developing an objective indicator of structural age discrimination are discussed.

Kokumi Taste Active Peptides Modulate Salt and Umami Taste.

Kokumi taste substances exemplified by γ-glutamyl peptides and Maillard Peptides modulate salt and umami tastes. However, the underlying mechanism for their action has not been delineated. Here, we investigated the effects of a kokumi taste active and inactive peptide fraction (500-10,000 Da) isolated from mature (FIIm) and immature (FIIim) Ganjang, a typical Korean soy sauce, on salt and umami taste responses in humans and rodents. Only FIIm (0.1-1.0%) produced a biphasic effect in rat chorda tympani (CT) taste nerve responses to lingual stimulation with 100 mM NaCl + 5 µM benzamil, a specific epithelial Na+ channel blocker. Both elevated temperature (42 °C) and FIIm produced synergistic effects on the NaCl + benzamil CT response. At 0.5% FIIm produced the maximum increase in rat CT response to NaCl + benzamil, and enhanced salt taste intensity in human subjects. At 2.5% FIIm enhanced rat CT response to glutamate that was equivalent to the enhancement observed with 1 mM IMP. In human subjects, 0.3% FIIm produced enhancement of umami taste. These results suggest that FIIm modulates amiloride-insensitive salt taste and umami taste at different concentration ranges in rats and humans.

Conversion of Mg-Li Bimetallic Alloys to Magnesium Alkoxide and Magnesium Oxide Ceramic Nanowires.

Technologically important composites with enhanced thermal and mechanical properties rely on the reinforcement by the high specific strength ceramic nanofibers or nanowires (NWs) with high aspect ratios. However, conventional synthesis routes to produce such ceramic NWs have prohibitively high cost. Now, direct transformation of bulk Mg-Li alloys into Mg alkoxide NWs is demonstrated without the use of catalysts, templates, expensive or toxic chemicals, or any external stimuli. This mechanism proceeds through the minimization of strain energy at the boundary of phase transformation front leading to the formation of ultra-long NWs with tunable dimensions. Such alkoxide NWs can be easily converted in air into ceramic MgO NWs with similar dimensions. The impact of the alloy grain size and Li content, synthesis temperature, inductive and steric effects of alkoxide groups on the diameter, length, composition, ductility, and oxidation of the produced NWs is discussed.

Cycle stability of conversion-type iron fluoride lithium battery cathode at elevated temperatures in polymer electrolyte composites.

Metal fluoride conversion cathodes offer a pathway towards developing lower-cost Li-ion batteries. Unfortunately, such cathodes suffer from extremely poor performance at elevated temperatures, which may prevent their use in large-scale energy storage applications. Here we report that replacing commonly used organic electrolytes with solid polymer electrolytes may overcome this hurdle. We demonstrate long-cycle stability for over 300 cycles at 50 °C attained in high-capacity (>450 mAh g-1) FeF2 cathodes. The absence of liquid solvents reduced electrolyte decomposition, while mechanical properties of the solid polymer electrolyte enhanced cathode structural stability. Our findings suggest that the formation of an elastic, thin and homogeneous cathode electrolyte interphase layer on active particles is a key for stable performance. The successful operation of metal fluorides at elevated temperatures opens a new avenue for their practical applications and future successful commercialization.

Mechanisms of Transformation of Bulk Aluminum-Lithium Alloys to Aluminum Metal-Organic Nanowires.

Fabrication and applications of lightweight, high load-bearing, thermally stable composite materials would benefit greatly from leveraging the high mechanical strength of ceramic nanowires (NWs) over conventional particles or micrometer-scale fibers. However, conventional synthesis routes to produce NWs are rather expensive. Recently we discovered a novel method to directly convert certain bulk bimetallic alloys to metal-organic NWs at ambient temperature and pressure. This method was demonstrated by a facile transformation of polycrystalline aluminum-lithium (AlLi) alloy particles to aluminum alkoxide NWs, which can be further transformed to mechanically robust aluminum oxide (Al2O3) NWs. However, the transformation mechanisms have not been clearly understood. Here, we conducted advanced materials characterization (via electron microscopy and nuclear magnetic resonance spectroscopies) and chemo-mechanical modeling to elucidate key physical and chemical mechanisms responsible for NWs formation. We further demonstrated that the content of Li metal in the AlLi alloy could be reduced to about 4 wt % without compromising the success of the NWs synthesis. This new mechanistic understanding may open new avenues for large-scale, low-cost manufacturing of NWs and nanofibers for a broad range of composites and flexible ceramic membranes.

Response to culturally competent drug treatment among homeless persons with different living arrangements.

This study investigated the association between program cultural competence and homeless individuals' drug use after treatment in Los Angeles County, California. Los Angeles County has the largest and most diverse population of homeless individuals in the nation. We randomly selected for analysis 52 drug-treatment programs and 2158 participants who identified as homeless in the Los Angeles County Participant Reporting System in 2011. We included their living arrangements (indoors and stable, indoors and unstable, and outdoors) and individual and program characteristics (particularly whether their programs used six culturally competent practices) in multilevel regression analyses. The outcome was days of primary drug use at discharge.Results showed that higher levels of staff personal involvement in minority communities (IRR=0.437; 95% CI=0.222, 0.861) and outreach to minority communities (IRR = 0.406; 95% CI=0.213, 0.771) were associated with fewer days of drug use at discharge. Homeless individuals living outdoors used their primary drug more often than any other group. Yet, compared to individuals with other living arrangements, when outdoor homeless individuals were treated by programs with the highest community resources and linkages (IRR=0.364; 95% CI=0.157, 0.844), they reported the fewest days of drug use. We discuss implications for program evaluation and community engagement policies and practices.

Experience of Domestic Violence During Childhood, Intimate Partner Violence, and the Deterrent Effect of Awareness of Legal Consequences.

The concept of intergenerational transmission of intimate partner violence (IPV) has been an important topic of research. Experts have contended that this brutal path in which violence is transmitted to subsequent generations may be avoidable. This study examined whether public perceptions of the legal regulation of IPV and the certainty of sanction deter the prevalence of IPV. Data from 3,800 households were obtained from a nationwide survey conducted in South Korea. Due to a skewed distribution of the prevalence of IPV, this study applied a zero-inflated Poisson (ZIP) model, which has been shown to address issues of skewed count variables. In addition, use of a ZIP model allowed us to examine factors associated with the occurrence and frequency of IPV. Results showed that child abuse experience and perceptions of the law were associated with the occurrence of IPV. Individuals who experienced child abuse were more likely to perpetrate IPV, whereas those aware of the law were less likely to perpetrate IPV. Witnessing IPV between parents was associated with an increased frequency of IPV. Results suggest that by increasing awareness of laws against domestic violence, IPV may be reduced or prevented.

Family functioning, resilience, and depression among North Korean refugees.

North Korean refugees in South Korea are at high risk of depression, but there are few studies exploring protective factors in this population. We hypothesized that family functioning (family adaptability and cohesion) and resilience would protect North Korean refugees from developing depressive symptoms. A subsample of 304 adult North Korean refugees drawn from the cross-sectional 2010 Nationwide Survey of Domestic Violence in South Korea was analyzed. Approximately 44% of respondents were identified as having depression, using scores on the Center for Epidemiological Studies Depression scale. In models capturing the full spectrum of depressive symptoms (continuous), family cohesion was significantly associated with depression, and the relationship was partially mediated by resilience. In models predicting clinical depression (dichotomous), resilience fully mediated the relationship between family cohesion and clinical depression. In contrast, family adaptability was not associated with depression or resilience in this sample. These findings suggest that assessing and enhancing family cohesion and resilience may be essential for professionals working with refugees, and that refugees without family support may be at particularly high risk for depression.

The Influence of Social Networks and Social Support on Health Among Older Koreans at High Risk of Depression.

BACKGROUND: Despite compelling evidence showing that social networks and social support are associated with depression, relatively little research is available on this topic for older Koreans at high risk of depression. This article aimed to examine the relationship among different types of social networks (family vs. friends), social support (instrumental vs. emotional), and perceived general health among older Koreans at high risk of depression. We would then test for possible differences in pathways between two age groups (60-74 years vs. 75 years and older). METHODS: Using data from the 2008 Survey of Elderly Life and Welfare Need, age 60-74 years (n = 2,815) and age 75 years and older (n = 1,784) were analyzed separately. Path analyses were used to examine the relationships among social network, support, and health among Korean older adults at high risk of depression. RESULTS: Findings highlighted the complex associations among social networks, social support, and perceived general health within old age. Moreover, this study called attention to the negative association between instrumental support from family networks and perceived general health among older Koreans aged 60-74 years at high risk of depression. CONCLUSIONS: The work discussed in this article would help inform the design of much needed and effective social intervention programs for the growing number of Korean older adults with depression.

Pilot Test of an Adapted, Evidence-Based HIV Sexual Risk Reduction Intervention for Homeless Women.

Women experiencing homelessness are at heightened risk for HIV, yet risk reduction interventions specifically designed for this population are lacking. This study reports on a pilot efficacy trial of a brief evidence-based intervention, Sister To Sister (STS), that we specifically adapted for homeless women in the temporary/emergency settings where they typically seek services. Seventy-nine women, recruited from three service sites in Los Angeles County, were assigned to the 40-min adapted STS intervention or an information-only control group. At 30-day follow-up, intervention participants reported significantly greater condom use, intentions to use condoms, and sexual impulse control (as well as marginally higher positive condom beliefs and condom self-efficacy) compared to control participants. Results provide preliminary evidence that HIV risk reduction can be achieved for homeless women through a brief skill-based intervention. A randomized controlled trial employing a longer follow-up period to monitor outcomes will be necessary to determine efficacy of the adapted intervention.

Adapting an evidence-based intervention for homeless women: engaging the community in shared decision-making.

As interest grows in the diffusion of evidence-based interventions (EBIs), there is increasing concern about how to mitigate implementation challenges; this paper concerns adapting an EBI for homeless women. Complementing earlier focus groups with homeless women, homeless service providers (n = 32) were engaged in focus groups to assess capacity, needs, and barriers with implementation of EBIs. Deductive analyses of data led to the selection of four EBIs. Six consensus groups were then undertaken; three each with homeless women (n = 24) and homeless service providers (n = 21). The selected EBI was adapted and pretested with homeless women (n = 9) and service providers (n = 6). The structured consensus group process provided great utility and affirmed the expertise of homeless women and service providers as experts in their domain. Engaging providers in the selection process reduced the structural barriers within agencies as obstacles to diffusion.