Nevin Manimala

J Speech Lang Hear Res. 2021 Mar 30:1-15. doi: 10.1044/2020_JSLHR-20-00471. Online ahead of print.

ABSTRACT

Purpose Generalized linear mixed-model (GLMM) and Bayesian methods together provide a framework capable of handling a wide variety of complex data commonly encountered across the communication sciences. Using language sample analysis, we demonstrate the utility of these methods in answering specific questions regarding the differences between discourse patterns of children who have experienced a traumatic brain injury (TBI), as compared to those with typical development. Method Language samples were collected from 55 adolescents ages 13-18 years, five of whom had experienced a TBI. We describe parameters relating to the productivity, syntactic complexity, and lexical diversity of language samples. A Bayesian GLMM is developed for each parameter of interest, relating these parameters to age, sex, prior history (TBI or typical development), and socioeconomic status, as well as the type of discourse sample (compare-contrast, cause-effect, or narrative). Statistical models are thoroughly described. Results Comparing the discourse of adolescents with TBI to those with typical development, substantial differences are detected in productivity and lexical diversity, while differences in syntactic complexity are more moderate. Female adolescents exhibited greater syntactic complexity, while male adolescents exhibited greater productivity and lexical diversity. Generally, our models suggest more advanced discourse among adolescents who are older or who have indicators of higher socioeconomic status. Differences relating to lecture type were also detected. Conclusions Bayesian and GLMM methods yield more informative and intuitive results than traditional statistical analyses, with a greater degree of confidence in model assumptions. We recommend that these methods be used more widely in language sample analysis. Supplemental Material https://doi.org/10.23641/asha.14226959.

PMID:33784201 | DOI:10.1044/2020_JSLHR-20-00471

J Speech Lang Hear Res. 2021 Mar 30:1-12. doi: 10.1044/2020_JSLHR-20-00561. Online ahead of print.

ABSTRACT

Purpose Analysis of connected speech in the field of adult neurogenic communication disorders is essential for research and clinical purposes, yet time and expertise are often cited as limiting factors. The purpose of this project was to create and evaluate an automated program to score and compute the measures from the Quantitative Production Analysis (QPA), an objective and systematic approach for measuring morphological and structural features of connected speech. Method The QPA was used to analyze transcripts of Cinderella stories from 109 individuals with acute-subacute left hemisphere stroke. Regression slopes and residuals were used to compare the results of manual scoring and automated scoring using the newly developed C-QPA command in CLAN, a set of programs for automatic analysis of language samples. Results The C-QPA command produced two spreadsheet outputs: an analysis spreadsheet with scores for each utterance in the language sample, and a summary spreadsheet with 18 score totals from the analysis spreadsheet and an additional 15 measures derived from those totals. Linear regression analysis revealed that 32 of the 33 measures had good agreement; auxiliary complexity index was the one score that did not have good agreement. Conclusions The C-QPA command can be used to perform automated analyses of language transcripts, saving time and training and providing reliable and valid quantification of connected speech. Transcribing in CHAT, the CLAN editor, also streamlined the process of transcript preparation for QPA and allowed for precise linking of media files to language transcripts for temporal analyses.

PMID:33784197 | DOI:10.1044/2020_JSLHR-20-00561

Am J Speech Lang Pathol. 2021 Mar 30:1-14. doi: 10.1044/2020_AJSLP-20-00110. Online ahead of print.

ABSTRACT

Purpose The purpose of this study was to evaluate changes in cognitive-communication performance using Woodcock-Johnson IV Tests (WJIV) from pre-injury baseline to post sport-related concussion. It was hypothesized that individual subtest performances would decrease postinjury in symptomatic individuals. Method This prospective longitudinal observational nested cohort study of collegiate athletes assessed cognitive-communicative performance at preseason baseline and postinjury. Three hundred and forty-two male and female undergraduates at high risk for sport-related concussion participated in preseason assessments, and 18 individuals met criteria post injury. WJIV subtest domains included Word Finding, Speeded Reading Comprehension, Auditory Comprehension, Verbal Working Memory, Story Retell, and Visual Processing (letter and number). The power calculation was not met, and therefore data were conservatively analyzed with descriptive statistics and a planned subgroup analysis based on symptomatology. Results Individual changes from baseline to postinjury were evaluated using differences in standard score performance. For symptomatic individuals, mean negative decreases in performance were found for Retrieval Fluency, Sentence Reading Fluency, Pattern Matchings, and all cluster scores postinjury. Individual performance declines also included decreases in story retell, verbal working memory, and visual processing. Conclusions This study identified within-subject WJIV performance decline in communication domains post sport-related concussion and reinforces that cognitive-communication dysfunction should be considered in mild traumatic brain injury. Key cognitive-communication areas included speeded naming, reading, and verbal memory, though oral comprehension was not sensitive to change. Future clinical research across diverse populations is needed to expand these preliminary findings.

PMID:33784181 | DOI:10.1044/2020_AJSLP-20-00110

Phys Rev Lett. 2021 Mar 12;126(10):104501. doi: 10.1103/PhysRevLett.126.104501.

ABSTRACT

The transitions between two states of a bistable system are investigated experimentally and analyzed in the framework of rare-event statistics. Considering a disk pendulum swept by a flow in a wind tunnel, bistability between two aerodynamic branches is observed, with spontaneous transitions from one branch to the other. The waiting times before spontaneous transition are distributed following a double exponential as a function of the control parameter, spanning 4 orders of magnitude in time, for both transitions. Inspired by a model originally applied to the transition to turbulence, we show that, for the disk pendulum, both transitions are controlled by rare events of the aerodynamic forces acting on the disk which we propose to link in particular to the vortex shedding-induced fluctuations. Beyond the aerodynamic aspects, this work has interesting fundamental outcomes regarding the broad field of rare events in out-of-equilibrium systems.

PMID:33784158 | DOI:10.1103/PhysRevLett.126.104501

Phys Rev Lett. 2021 Mar 12;126(10):101601. doi: 10.1103/PhysRevLett.126.101601.

ABSTRACT

We study the holographic complexity conjectures for rotating black holes, uncovering a relationship between the complexity of formation and the thermodynamic volume of the black hole. We suggest that it is the thermodynamic volume and not the entropy that controls the complexity of formation of large black holes in both the complexity equals action and complexity equals volume proposals in general. Our proposal reduces to known results involving the entropy in settings where the thermodynamic volume and entropy are not independent, but has broader scope. Assuming a conjectured inequality is obeyed by the thermodynamic volume, we establish that the complexity of formation is bounded from below by the entropy for large black holes.

PMID:33784155 | DOI:10.1103/PhysRevLett.126.101601

Phys Rev Lett. 2021 Mar 12;126(10):102001. doi: 10.1103/PhysRevLett.126.102001.

ABSTRACT

We report a study of the processes of e^{+}e^{-}→K^{+}D_{s}^{-}D^{*0} and K^{+}D_{s}^{*-}D^{0} based on e^{+}e^{-} annihilation samples collected with the BESIII detector operating at BEPCII at five center-of-mass energies ranging from 4.628 to 4.698 GeV with a total integrated luminosity of 3.7 fb^{-1}. An excess of events over the known contributions of the conventional charmed mesons is observed near the D_{s}^{-}D^{*0} and D_{s}^{*-}D^{0} mass thresholds in the K^{+} recoil-mass spectrum for events collected at sqrt[s]=4.681 GeV. The structure matches a mass-dependent-width Breit-Wigner line shape, whose pole mass and width are determined as (3982.5_{-2.6}^{+1.8}±2.1) MeV/c^{2} and (12.8_{-4.4}^{+5.3}±3.0) MeV, respectively. The first uncertainties are statistical and the second are systematic. The significance of the resonance hypothesis is estimated to be 5.3 σ over the contributions only from the conventional charmed mesons. This is the first candidate for a charged hidden-charm tetraquark with strangeness, decaying into D_{s}^{-}D^{*0} and D_{s}^{*-}D^{0}. However, the properties of the excess need further exploration with more statistics.

PMID:33784133 | DOI:10.1103/PhysRevLett.126.102001

Int J Biostat. 2021 Mar 30. doi: 10.1515/ijb-2020-0039. Online ahead of print.

ABSTRACT

A latent factor model for count data is popularly applied in deconvoluting mixed signals in biological data as exemplified by sequencing data for transcriptome or microbiome studies. Due to the availability of pure samples such as single-cell transcriptome data, the accuracy of the estimates could be much improved. However, the advantage quickly disappears in the presence of excessive zeros. To correctly account for this phenomenon in both mixed and pure samples, we propose a zero-inflated non-negative matrix factorization and derive an effective multiplicative parameter updating rule. In simulation studies, our method yielded the smallest bias. We applied our approach to brain gene expression as well as fecal microbiome datasets, illustrating the superior performance of the approach. Our method is implemented as a publicly available R-package, iNMF.

PMID:33783171 | DOI:10.1515/ijb-2020-0039

J Korean Med Sci. 2021 Mar 29;36(12):e80. doi: 10.3346/jkms.2021.36.e80.

ABSTRACT

BACKGROUND: Spinal cord injury (SCI) is a serious clinical condition that impacts a patient’s physical, psychological, and socio-economic status. The aim of this pilot study was to evaluate the effects of training with a newly developed powered wearable exoskeleton (Hyundai Medical Exoskeleton [H-MEX]) on functional mobility, physiological health, and quality of life in non-ambulatory SCI patients.

METHODS: Participants received 60 minutes of walking training with a powered exoskeleton 3 times per week for 10 weeks (total 30 sessions). The 6-minute walking test (6MWT) and timed-up-and-go test (TUGT) were performed to assess ambulatory function. The physiological outcomes of interest after exoskeleton-assisted walking training were spasticity, pulmonary function, bone mineral density, colon transit time, and serum inflammatory markers. Effects of walking training on subjective outcomes were estimated by the Korean version of the Falls Efficacy Scale-International and the 36-Item Short-Form Health Survey version 2.

RESULTS: Ten participants finished 30 sessions of training and could ambulate independently. No severe adverse events were reported during the study. After training, the mean distance walked in the 6MWT (49.13 m) was significantly enhanced compared with baseline (20.65 m). The results of the TUGT also indicated a statistically significant improvement in the times required to stand up, walk 3 m and sit down. Although not statistically significant, clinically meaningful changes in some secondary physiological outcomes and/or quality of life were reported in some participants.

CONCLUSION: In conclusion, this study demonstrated that the newly developed wearable exoskeleton, H-MEX is safe and feasible for non-ambulatory SCI patients, and may have potential to improve quality of life of patients by assisting bipedal ambulation. These results suggest that the H-MEX can be considered a beneficial device for chronic non-ambulatory SCI patients.

TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04055610.

PMID:33783145 | DOI:10.3346/jkms.2021.36.e80

Clin Exp Dent Res. 2021 Mar 29. doi: 10.1002/cre2.422. Online ahead of print.

ABSTRACT

OBJECTIVES: To assess if wearing a mouth guard impacts maximal aerobic capacity in amateur boxers.

MATERIALS AND METHODS: A prospective crossover cohort (pilot) study was conducted to assess maximal aerobic capacity in amateur boxers using the 20 m multi stage fitness test (MSFT). Two primary outcomes measures were recorded: (1) the maximum oxygen uptake (peak VO₂ -mL/kg/min) and (2) distance run (meters-m). Thirteen amateur boxers completed the MSFT 7 days apart under control (no mouth guard-C) and intervention conditions (mouth guard-MG). Participants also submitted data on height, weight, type of mouth guard and Rate of Perceived Exertion (RPE) during the test.

STATISTICS: Paired T-test.

RESULTS: Mouth guard use was shown to reduce peak VO₂ and distance run during the 20 m MSFT from 56.31 to 54.12 mL/kg/min and 2572 to 2380 m respectively (p < 0.05). Twelve out of 13 participants wore a Boil & Bite mouthguard and recorded lower peak VO₂ scores (-4.38%) when wearing a mouth guard compared to control conditions, (Mean = -2.46 mL/kg/min, Range of decrease = 4.2-0.9 mL/kg/min; p < 0.05). Ten participants submitted data on RPE-One participant with a custom made mouthguard reported no change in RPE in mouthguard conditions, while nine participants reported an average (+30.5%) increase in mean RPE in Boil & Bite mouthguard conditions compared to control conditions.

CONCLUSIONS: Boil & Bite mouth guard use was shown to significantly reduce aerobic performance in amateur boxers and increase the perceived rate of exertion during the 20 m MSFT.

PMID:33783141 | DOI:10.1002/cre2.422