Preschool children's physical activity in the home, childcare and neighbourhood environment: A latent profile analysis using device-based measures.

Based on the socioecological conceptual model, the physical environment within the home, childcare and neighbourhood domains are key factors that influence preschool children's physical activity; however, the relative importance of each of these domains for preschool children's physical activity is unclear. We explored the physical environment characteristics within three latent profiles of 115 preschool children aged 2-5 years based on where they accumulated moderate-to-vigorous physical activity (MVPA) across five GPS-derived environmental domains. The three profiles were "Active at home" (n = 41), "Active except close to home" (n = 61), and "Active except in local neighbourhood" (n = 13). Compared to other profiles, "Active at home" had fewer parks and playgrounds within their 500-1600 m neighbourhood. Findings suggest preschool children's MVPA profiles are reflections of their physical environmental opportunities.

Comparative Efficacy and Safety of Self-Expandable vs. Balloon-Expandable Stent Grafts in Visceral Artery Aneurysm Management.

PURPOSE: This study assesses the efficacy and safety of self-expandable (SE) versus balloon-expandable (BE) stent grafts for managing visceral artery aneurysms (VAAs), focusing on procedural success and complication rates. MATERIALS AND METHODS: We conducted a retrospective analysis of VAA patients treated at our institution from April 2006 to September 2021. The study reviewed patient demographics, aneurysm characteristics, treatment details, and outcomes, including endoleaks. RESULTS: Among the 23 patients analyzed, splenic artery aneurysms represented 44% of cases. Fifteen patients were treated with balloon-expandable stent grafts (BE SGs), and eight patients were treated with self-expandable stent grafts (SE SGs). For saccular aneurysms, the average neck size was 10.10 ± 8.70 mm in the BE group versus 18.50 ± 3.40 mm in the SE group (p = 0.23), with an average sac size of 20.10 ± 18.9 mm in the BE group versus 15.60 ± 12.7 mm in the SE group (p = 0.16). The average sac-to-neck ratio was 1.69 ± 2.23 in the BE group versus 1.38 ± 0.33 in the SE group (p = 0.63). The BE group exhibited a significantly higher endoleak rate (60%) compared to the SE group (12.5%; p = 0.03). CONCLUSIONS: While further investigation is needed to fully assess the outcomes of stent graft treatment for VAAs, initial data show a significantly higher endoleak rate with BE SGs compared to SE SGs. The SE SGs may offer better outcomes due to their superior ability to conform to tortuous and mobile visceral arteries.

Mechanical Thrombectomy for High-Risk Pulmonary Embolism: Insights From the US Cohort of the FLASH Registry.

Background: Acute mortality for high-risk, or massive, pulmonary embolism (PE) is almost 30% even when treated using advanced therapies. This analysis assessed the safety and effectiveness of mechanical thrombectomy (MT) for high-risk PE. Methods: The prospective, multicenter FlowTriever All-comer Registry for Patient Safety and Hemodynamics (FLASH) study is designed to evaluate real-world PE patient outcomes after MT with the FlowTriever System (Inari Medical). In this study, acute outcomes through 30 days were evaluated for the subset of patients with high-risk PE as determined by the sites and following European Society of Cardiology guidelines. An independent medical monitor adjudicated adverse events (AEs), including major AEs: device-related mortality, major bleeding, or intraprocedural device-related or procedure-related AEs. Results: Of the 799 patients in the US cohort, 63 (7.9%) were diagnosed with high-risk PE; 30 (47.6%) patients showed a systolic blood pressure <90 mm Hg, 29 (46.0%) required vasopressors, and 4 (6.3%) experienced cardiac arrest. The mean age of patients with high-risk PE was 59.4 ± 15.6 years, and 34 (54.0%) were women. At baseline, 45 (72.6%) patients were tachycardic, 18 (54.5%) showed elevated lactate levels of ≥2.5 mM, and 21 (42.9%) demonstrated depressed cardiac index of <2 L/min/m2. Immediately after MT, heart rate improved to 93.5 ± 17.9 bpm. Twenty-five (42.4%) patients did not require an overnight stay in the intensive care unit, and no mortalities or major AEs occurred through 48 hours. Moreover, no mortalities occurred in 61 (96.8%) patients followed up through the 30-day visit. Conclusions: In this cohort of 63 patients with high-risk PE, MT was safe and effective, with no acute mortalities reported. Further prospective data are needed in this population.

Associations Between Music and Dance Relationships, Rhythmic Proficiency, and Spatiotemporal Movement Modulation Ability in Adults with and without Mild Cognitive Impairment.

Background: Personalized dance-based movement therapies may improve cognitive and motor function in individuals with mild cognitive impairment (MCI), a precursor to Alzheimer's disease. While age- and MCI-related deficits reduce individuals' abilities to perform dance-like rhythmic movement sequences (RMS)-spatial and temporal modifications to movement-it remains unclear how individuals' relationships to dance and music affect their ability to perform RMS. Objective: Characterize associations between RMS performance and music or dance relationships, as well as the ability to perceive rhythm and meter (rhythmic proficiency) in adults with and without MCI. Methods: We used wearable inertial sensors to evaluate the ability of 12 young adults (YA; age = 23.9±4.2 years; 9F), 26 older adults without MCI (OA; age = 68.1±8.5 years; 16F), and 18 adults with MCI (MCI; age = 70.8±6.2 years; 10F) to accurately perform spatial, temporal, and spatiotemporal RMS. To quantify self-reported music and dance relationships and rhythmic proficiency, we developed Music (MRQ) and Dance Relationship Questionnaires (DRQ), and a rhythm assessment (RA), respectively. We correlated MRQ, DRQ, and RA scores against RMS performance for each group separately. Results: The OA and YA groups exhibited better MRQ and RA scores than the MCI group (p < 0.006). Better MRQ and RA scores were associated with better temporal RMS performance for only the YA and OA groups (r2 = 0.18-0.41; p < 0.045). DRQ scores were not associated with RMS performance in any group. Conclusions: Cognitive deficits in adults with MCI likely limit the extent to which music relationships or rhythmic proficiency improve the ability to perform temporal aspects of movements performed during dance-based therapies.

Quantifying allele-specific CRISPR editing activity with CRISPECTOR2.0.

Off-target effects present a significant impediment to the safe and efficient use of CRISPR-Cas genome editing. Since off-target activity is influenced by the genomic sequence, the presence of sequence variants leads to varying on- and off-target profiles among different alleles or individuals. However, a reliable tool that quantifies genome editing activity in an allelic context is not available. Here, we introduce CRISPECTOR2.0, an extended version of our previously published software tool CRISPECTOR, with an allele-specific editing activity quantification option. CRISPECTOR2.0 enables reference-free, allele-aware, precise quantification of on- and off-target activity, by using de novo sample-specific single nucleotide variant (SNV) detection and statistical-based allele-calling algorithms. We demonstrate CRISPECTOR2.0 efficacy in analyzing samples containing multiple alleles and quantifying allele-specific editing activity, using data from diverse cell types, including primary human cells, plants, and an original extensive human cell line database. We identified instances where an SNV induced changes in the protospacer adjacent motif sequence, resulting in allele-specific editing. Intriguingly, differential allelic editing was also observed in regions carrying distal SNVs, hinting at the involvement of additional epigenetic factors. Our findings highlight the importance of allele-specific editing measurement as a milestone in the adaptation of efficient, accurate, and safe personalized genome editing.

A polygenic risk score for the QT interval is an independent predictor of drug-induced QT prolongation.

Drug-induced QT prolongation (diLQTS), and subsequent risk of torsade de pointes, is a major concern with use of many medications, including for non-cardiac conditions. The possibility that genetic risk, in the form of polygenic risk scores (PGS), could be integrated into prediction of risk of diLQTS has great potential, although it is unknown how genetic risk is related to clinical risk factors as might be applied in clinical decision-making. In this study, we examined the PGS for QT interval in 2500 subjects exposed to a known QT-prolonging drug on prolongation of the QT interval over 500ms on subsequent ECG using electronic health record data. We found that the normalized QT PGS was higher in cases than controls (0.212±0.954 vs. -0.0270±1.003, P = 0.0002), with an unadjusted odds ratio of 1.34 (95%CI 1.17-1.53, P<0.001) for association with diLQTS. When included with age and clinical predictors of QT prolongation, we found that the PGS for QT interval provided independent risk prediction for diLQTS, in which the interaction for high-risk diagnosis or with certain high-risk medications (amiodarone, sotalol, and dofetilide) was not significant, indicating that genetic risk did not modify the effect of other risk factors on risk of diLQTS. We found that a high-risk cutoff (QT PGS ≥ 2 standard deviations above mean), but not a low-risk cutoff, was associated with risk of diLQTS after adjustment for clinical factors, and provided one method of integration based on the decision-tree framework. In conclusion, we found that PGS for QT interval is an independent predictor of diLQTS, but that in contrast to existing theories about repolarization reserve as a mechanism of increasing risk, the effect is independent of other clinical risk factors. More work is needed for external validation in clinical decision-making, as well as defining the mechanism through which genes that increase QT interval are associated with risk of diLQTS.

A multi-method exploration of a cardiac rehabilitation service delivered by registered Clinical Exercise Physiologists in the UK: key learnings for current and new services.

BACKGROUND: Cardiac rehabilitation has been identified as having the most homogenous clinical exercise service structure in the United Kingdom (UK), but inconsistencies are evident in staff roles and qualifications within and across services. The recognition of Clinical Exercise Physiologists (CEPs) as a registered health professional in 2021 in the UK, provides a potential solution to standardise the cardiac rehabilitation workforce. This case study examined, in a purposefully selected cardiac exercise service that employed registered CEPs, (i) how staff knowledge, skills and competencies contribute to the provision of the service, (ii) how these components assist in creating effective service teams, and (iii) the existing challenges from staff and patient perspectives. METHODS: A multi-method qualitative approach (inc., semi-structured interviews, observations, field notes and researcher reflections) was employed with the researcher immersed for 12-weeks within the service. The Consolidated Framework for Implementation Research was used as an overarching guide for data collection. Data derived from registered CEPs (n = 5), clinical nurse specialists (n = 2), dietitians (n = 1), service managers/leads (n = 2) and patients (n = 7) were thematically analysed. RESULTS: Registered CEPs delivered innovative exercise prescription based on their training, continued professional development (CPD), academic qualifications and involvement in research studies as part of the service. Exposure to a wide multidisciplinary team (MDT) allowed skill and competency transfer in areas such as clinical assessments. Developing an effective behaviour change strategy was challenging with delivery of lifestyle information more effective during less formal conversations compared to timetabled education sessions. CONCLUSIONS: Registered CEPs have the specialist knowledge and skills to undertake and implement the latest evidence-based exercise prescription in a cardiac rehabilitation setting. An MDT service structure enables a more effective team upskilling through shared peer experiences, observations and collaborative working between healthcare professionals.

Development and validation of the Atri-Risk Conduction Index risk score to predict risk of atrial fibrillation after typical atrial flutter ablation.

BACKGROUND: Identification of patients at risk for atrial fibrillation (AF) after typical atrial flutter (tAFL) ablation is important to guide monitoring and treatment. OBJECTIVE: The purpose of this study was to create and validate a risk score to predict AF after tAFL ablation METHODS: We identified patients who underwent tAFL ablation with no AF history between 2017 and 2022 and randomly allocated to derivation and validation cohorts. We collected clinical variables and measured conduction parameters in sinus rhythm on an electrophysiology recording system (CardioLab, GE Healthcare). Univariate and multivariate logistic regressions (LogR) were used to evaluate association with AF development. RESULTS: A total of 242 consecutive patients (81% male; mean age 66 ± 11 years) were divided into derivation (n =142) and validation (n = 100) cohorts. Forty-two percent developed AF over median follow-up of 330 days. In multivariate LogR (derivation cohort), proximal to distal coronary sinus time (pCS-dCS) ≥70 ms (odds ratio [OR] 16.7; 95% confidence interval [CI] 5.6-49), pCS time ≥36 ms (OR 4.5; 95% CI 1.5-13), and CHADS2-VASc score ≥3 (OR 4.3; 95% CI 1.6-11.8) were independently associated with new AF during follow-up. The Atri-Risk Conduction Index (ARCI) score was created with 0 as minimal and 4 as high-risk using pCS-dCS ≥70 ms = 2 points; pCS ≥36 ms = 1 point; and CHADS2-VASc score ≥3 = 1 point. In the validation cohort, 0% of patients with ARCI score = 0 developed AF, whereas 89% of patients with ARCI score = 4 developed AF. CONCLUSION: We developed and validated a risk score using atrial conduction parameters and clinical risk factors to predict AF after tAFL ablation. It stratifies low-, moderate-, and high-risk patients and may be helpful in individualizing approaches to AF monitoring and anticoagulation.

A systematic review of diagnostic and interventional techniques in non-occlusive hepatic artery hypoperfusion syndrome.

OBJECTIVE: This systematic review aims to elucidate the diagnostic capabilities of imaging techniques in identifying Non-Occlusive Hepatic Artery Hypoperfusion Syndrome (NOHAH) and to evaluate the efficacy and outcomes of splenic artery embolization (SAE), including the choice and placement of embolic agents. MATERIALS AND METHODS: A comprehensive literature search was conducted using PubMed, CINAHL, and Scopus databases, adhering to PRISMA guidelines. Fifteen studies encompassing 240 patients treated with embolization (using coils or Amplatzer Vascular Plugs (AVP)) were analyzed. Key metrics assessed included patient demographics, embolization techniques, embolic agents, technical success, radiologic findings pre- and post-embolization, and complication rates. RESULTS: Among the 240 patients studied, 177 (73.8%) were reported by gender, with a majority being male (127/177, 71.7%). Doppler ultrasonography (DUS) emerged as the primary initial screening tool in 80% of studies. The hepatic arterial resistive index (RI) was a critical parameter, with mean values significantly decreasing from 0.84 pre-embolization to 0.70 post-embolization (p < 0.001). All cases confirmed technical success via digital subtraction angiography, revealing delayed hepatic arterial filling without stenosis or thrombosis. Coils were the predominant embolic agent, used in 80.8% of patients, followed by AVP in 16.3%. The overall mortality rate was 4.58%, with 29 major and 3 minor complications noted. Notably, proximal placement of coils in the splenic artery was associated with lower mortality rates compared to distal placement and showed comparable complication rates to AVPs. CONCLUSION: DUS is a reliable screening modality for NOHAH, with post-SAE assessments showing significant improvements. The choice and location of embolization significantly impact patient outcomes, with proximal placement of coils emerging as a preferable strategy due to lower mortality rates and comparable complication profiles to alternative methods.

Life-long music and dance relationships inform impressions of music- and dance-based movement therapies in individuals with and without mild cognitive impairment.

Background: No effective therapies exist to prevent degeneration from Mild Cognitive Impairment (MCI) to Alzheimer's disease. Therapies integrating music and/or dance are promising as effective, non-pharmacological options to mitigate cognitive decline. Objective: To deepen our understanding of individuals' relationships (i.e., histories, experiences and attitudes) with music and dance that are not often incorporated into music- and dance-based therapeutic design, yet may affect therapeutic outcomes. Methods: Eleven older adults with MCI and five of their care partners/ spouses participated (4M/12F; Black: n=4, White: n=10, Hispanic/ Latino: n=2; Age: 71.4±9.6). We conducted focus groups and administered questionnaires that captured aspects of participants' music and dance relationships. We extracted emergent themes from four major topics, including: (1) experience and history, (2) enjoyment and preferences, (3) confidence and barriers, and (4) impressions of music and dance as therapeutic tools. Results: Thematic analysis revealed participants' positive impressions of music and dance as potential therapeutic tools, citing perceived neuropsychological, emotional, and physical benefits. Participants viewed music and dance as integral to their lives, histories, and identities within a culture, family, and/ or community. Participants also identified lifelong engagement barriers that, in conjunction with negative feedback, instilled persistent low self-efficacy regarding dancing and active music engagement. Questionnaires verified individuals' moderately-strong music and dance relationships, strongest in passive forms of music engagement (e.g., listening). Conclusions: Our findings support that individuals' music and dance relationships and the associated perceptions toward music and dance therapy may be valuable considerations in enhancing therapy efficacy, participant engagement and satisfaction for individuals with MCI.

Gait signature changes with walking speed are similar among able-bodied young adults despite persistent individual-specific differences.

Understanding individuals' distinct movement patterns is crucial for health, rehabilitation, and sports. Recently, we developed a machine learning-based framework to show that "gait signatures" describing the neuromechanical dynamics governing able-bodied and post-stroke gait kinematics remain individual-specific across speeds. However, we only evaluated gait signatures within a limited speed range and number of participants, using only sagittal plane (i.e., 2D) joint angles. Here we characterized changes in gait signatures across a wide range of speeds, from very slow (0.3 m/s) to exceptionally fast (above the walk-to-run transition speed) in 17 able-bodied young adults. We further assessed whether 3D kinematic and/or kinetic (ground reaction forces, joint moments, and powers) data would improve the discrimination of gait signatures. Our study showed that gait signatures remained individual-specific across walking speeds: Notably, 3D kinematic signatures achieved exceptional accuracy (99.8%, confidence interval (CI): 99.1-100%) in classifying individuals, surpassing both 2D kinematics and 3D kinetics. Moreover, participants exhibited consistent, predictable linear changes in their gait signatures across the entire speed range. These changes were associated with participants' preferred walking speeds, balance ability, cadence, and step length. These findings support gait signatures as a tool to characterize individual differences in gait and predict speed-induced changes in gait dynamics.

Effects of urban-induced mutations on ecology, evolution and health.

Increasing evidence suggests that urbanization is associated with higher mutation rates, which can affect the health and evolution of organisms that inhabit cities. Elevated pollution levels in urban areas can induce DNA damage, leading to de novo mutations. Studies on mutations induced by urban pollution are most prevalent in humans and microorganisms, whereas studies of non-human eukaryotes are rare, even though increased mutation rates have the potential to affect organisms and their populations in contemporary time. Our Perspective explores how higher mutation rates in urban environments could impact the fitness, ecology and evolution of populations. Most mutations will be neutral or deleterious, and higher mutation rates associated with elevated pollution in urban populations can increase the risk of cancer in humans and potentially other species. We highlight the potential for urban-driven increased deleterious mutational loads in some organisms, which could lead to a decline in population growth of a wide diversity of organisms. Although beneficial mutations are expected to be rare, we argue that higher mutation rates in urban areas could influence adaptive evolution, especially in organisms with short generation times. Finally, we explore avenues for future research to better understand the effects of urban-induced mutations on the fitness, ecology and evolution of city-dwelling organisms.

Insight into the adaptive role of arachnid genome-wide duplication through chromosome-level genome assembly of the Western black widow spider.

Although spiders are one of the most diverse groups of arthropods, the genetic architecture of their evolutionary adaptations is largely unknown. Specifically, ancient genome-wide duplication occurring during arachnid evolution ~450 mya resulted in a vast assembly of gene families, yet the extent to which selection has shaped this variation is understudied. To aid in comparative genome sequence analyses, we provide a chromosome-level genome of the Western black widow spider (Latrodectus hesperus)-a focus due to its silk properties, venom applications, and as a model for urban adaptation. We used long-read and Hi-C sequencing data, combined with transcriptomes, to assemble 14 chromosomes in a 1.46 Gb genome, with 38,393 genes annotated, and a BUSCO score of 95.3%. Our analyses identified high repetitive gene content and heterozygosity, consistent with other spider genomes, which has led to challenges in genome characterization. Our comparative evolutionary analyses of eight genomes available for species within the Araneoidea group (orb weavers and their descendants) identified 1,827 single-copy orthologs. Of these, 155 exhibit significant positive selection primarily associated with developmental genes, and with traits linked to sensory perception. These results support the hypothesis that several traits unique to spiders emerged from the adaptive evolution of ohnologs-or retained ancestrally duplicated genes-from ancient genome-wide duplication. These comparative spider genome analyses can serve as a model to understand how positive selection continually shapes ancestral duplications in generating novel traits today within and between diverse taxonomic groups.

Parents on the Concept of Physical Literacy: What Do They Know, What Do They Do, and What Do They Want?

Physical literacy development in early childhood, viewed by many as the foundation for lifelong physical activity engagement, is significantly influenced by parents. Our aim was to explore parents' understanding of physical literacy and gain insight into their perspectives on physical literacy promotion. We recruited 18 parents of children between 5 and 8 years old in Australia. Using semistructured interviews and thematic analysis, we identified several key issues regarding parents' understanding and implementation of physical literacy. Parents expressed interest in improving their implementation of physical literacy practices and had (often unintentionally) provided support for physical literacy subcomponents in the past. However, they described difficulties prioritizing physical literacy above other parental demands and expressed conflicting perceptions regarding where the responsibility should lie for developing their child's physical literacy (e.g., at home or at school). To ensure that the physical literacy "message" reaches parents, we encourage physical literacy promoters to consider the target (e.g., responsibility, priorities, and awareness) of their promotional strategies. Further investigation into the influence of sociocultural and economic factors on parents' understanding and application of physical literacy is warranted.

Efficient DNA-based data storage using shortmer combinatorial encoding.

Data storage in DNA has recently emerged as a promising archival solution, offering space-efficient and long-lasting digital storage solutions. Recent studies suggest leveraging the inherent redundancy of synthesis and sequencing technologies by using composite DNA alphabets. A major challenge of this approach involves the noisy inference process, obstructing large composite alphabets. This paper introduces a novel approach for DNA-based data storage, offering, in some implementations, a 6.5-fold increase in logical density over standard DNA-based storage systems, with near-zero reconstruction error. Combinatorial DNA encoding uses a set of clearly distinguishable DNA shortmers to construct large combinatorial alphabets, where each letter consists of a subset of shortmers. We formally define various combinatorial encoding schemes and investigate their theoretical properties. These include information density and reconstruction probabilities, as well as required synthesis and sequencing multiplicities. We then propose an end-to-end design for a combinatorial DNA-based data storage system, including encoding schemes, two-dimensional (2D) error correction codes, and reconstruction algorithms, under different error regimes. We performed simulations and show, for example, that the use of 2D Reed-Solomon error correction has significantly improved reconstruction rates. We validated our approach by constructing two combinatorial sequences using Gibson assembly, imitating a 4-cycle combinatorial synthesis process. We confirmed the successful reconstruction, and established the robustness of our approach for different error types. Subsampling experiments supported the important role of sampling rate and its effect on the overall performance. Our work demonstrates the potential of combinatorial shortmer encoding for DNA-based data storage and describes some theoretical research questions and technical challenges. Combining combinatorial principles with error-correcting strategies, and investing in the development of DNA synthesis technologies that efficiently support combinatorial synthesis, can pave the way to efficient, error-resilient DNA-based storage solutions.

Developing and testing a web-based platform for antiretroviral therapy (ART) adherence support among adolescents and young adults (AYA) living with HIV.

Objective: Describe the development and testing of a web-based platform for antiretroviral treatment (ART) adherence support among HIV+ adolescents and young adults (AYA) in a randomized controlled trial (RCT). Methods: A seven-member multi-disciplinary team operationalized the flat, password protected, web-based platform. Manualized protocols guided the objectives and content for each of the eight web-based sessions. Team members evaluated usability and content validity. Client satisfaction and perceived ease of use was evaluated with the first ten HIV+ AYA participants. Results: The web-based platform was developed, evaluated, refined, implemented and pilot tested between September 2020 to April 2022. Usability was rated as high; the evaluation of content validity showed an excellent fit between session content and objectives. HIV+ AYA participants (mean age = 24.2 years) were satisfied with the quality, type, and amount of support/education received, and found the platform easy to use, operate, and navigate. Average time spent per session was 6.5 min. Conclusion: Findings support the usability, validity, acceptability, and feasibility of this web-based platform for ART adherence support among HIV+ AYA. Innovation: Our research and findings are responsive to research gaps and the need for transparency in the methodological development and testing of web-based control arms for ART adherence support among HIV+ AYA.

MetaWin 3: open-source software for meta-analysis.

The rise of research synthesis and systematic reviews over the last 25 years has been aided by a series of software packages providing simple and accessible GUI interfaces which are intuitively easy to use by novice analysts and users. Development of many of these packages has been abandoned over time due to a variety of factors, leaving a gap in the software infrastructure available for meta-analysis. To fulfill the continued demand for a GUI-based meta-analytic system, we have now released MetaWin 3 as free, open-source, multi-platform software. MetaWin3 is written in Python and developed from scratch relative to earlier versions. The codebase is available on Github, with pre-compiled executables for both Windows and macOS available from the MetaWin website. MetaWin includes standardized effect size calculations, exploratory and publication bias analyses, and allows for both simple and complex explanatory models of variation within a meta-analytic framework, including meta-regression, using traditional least-squares/moments estimation.

Associations between music and dance relationships, rhythmic proficiency, and spatiotemporal movement modulation ability in adults with and without mild cognitive impairment.

Background: Personalized dance-based movement therapies may improve cognitive and motor function in individuals with mild cognitive impairment (MCI), a precursor to Alzheimer's disease. While age- and MCI-related deficits reduce individuals' abilities to perform dance-like rhythmic movement sequences (RMS)-spatial and temporal modifications to movement-it remains unclear how individuals' relationships to dance and music affect their ability to perform RMS. Objective: Characterize associations between RMS performance and music or dance relationships, as well as the ability to perceive rhythm and meter (rhythmic proficiency) in adults with and without MCI. Methods: We used wearable inertial sensors to evaluate the ability of 12 young adults (YA; age=23.9±4.2 yrs; 9F), 26 older adults without MCI (OA; age=68.1±8.5 yrs; 16F), and 18 adults with MCI (MCI; age=70.8±6.2 yrs; 10F) to accurately perform spatial, temporal, and spatiotemporal RMS. To quantify self-reported music and dance relationships and rhythmic proficiency, we developed Music (MRQ) and Dance Relationship Questionnaires (DRQ), and a rhythm assessment (RA), respectively. We correlated MRQ, DRQ, and RA scores against RMS performance for each group separately. Results: The OA and YA groups exhibited better MRQ and RA scores than the MCI group (p<0.006). Better MRQ and RA scores were associated with better temporal RMS performance for only the YA and OA groups (r2=0.18-0.41; p<0.045). DRQ scores were not associated with RMS performance in any group. Conclusions: Cognitive deficits in adults with MCI likely limit the extent to which music relationships or rhythmic proficiency improve the ability to perform temporal aspects of movements performed during dance-based therapies.

Quantifying changes in individual-specific template-based representations of center-of-mass dynamics during walking with ankle exoskeletons using Hybrid-SINDy.

Ankle exoskeletons alter whole-body walking mechanics, energetics, and stability by altering center-of-mass (CoM) motion. Controlling the dynamics governing CoM motion is, therefore, critical for maintaining efficient and stable gait. However, how CoM dynamics change with ankle exoskeletons is unknown, and how to optimally model individual-specific CoM dynamics, especially in individuals with neurological injuries, remains a challenge. Here, we evaluated individual-specific changes in CoM dynamics in unimpaired adults and one individual with post-stroke hemiparesis while walking in shoes-only and with zero-stiffness and high-stiffness passive ankle exoskeletons. To identify optimal sets of physically interpretable mechanisms describing CoM dynamics, termed template signatures, we leveraged hybrid sparse identification of nonlinear dynamics (Hybrid-SINDy), an equation-free data-driven method for inferring sparse hybrid dynamics from a library of candidate functional forms. In unimpaired adults, Hybrid-SINDy automatically identified spring-loaded inverted pendulum-like template signatures, which did not change with exoskeletons (p > 0.16), except for small changes in leg resting length (p < 0.001). Conversely, post-stroke paretic-leg rotary stiffness mechanisms increased by 37-50% with zero-stiffness exoskeletons. While unimpaired CoM dynamics appear robust to passive ankle exoskeletons, how neurological injuries alter exoskeleton impacts on CoM dynamics merits further investigation. Our findings support Hybrid-SINDy's potential to discover mechanisms describing individual-specific CoM dynamics with assistive devices.