Resonant Akhmediev breathers.

Modulation instability is a phenomenon in which a minor disturbance within a carrier wave gradually amplifies over time, leading to the formation of a series of compressed waves with higher amplitudes. In terms of frequency analysis, this process results in the generation of new frequencies on both sides of the original carrier wave frequency. We study the impact of fourth-order dispersion on this modulation instability in the context of nonlinear optics that lead to the formation of a series of pulses in the form of Akhmediev breather. The Akhmediev breather, a solution to the nonlinear Schrödinger equation, precisely elucidates how modulation instability produces a sequence of periodic pulses. We observe that when weak fourth-order dispersion is present, significant resonant radiation occurs, characterized by two modulation frequencies originating from different spectral bands. As an Akhmediev breather evolves, these modulation frequencies interact, resulting in a resonant amplification of spectral sidebands on either side of the breather. When fourth-order dispersion is of intermediate strength, the spectral bandwidth of the Akhmediev breather diminishes due to less pronounced resonant interactions, while stronger dispersion causes the merging of the two modulation frequency bands into a single band. Throughout these interactions, we witness a complex energy exchange process among the phase-matched frequency components. Moreover, we provide a precise explanation for the disappearance of the Akhmediev breather under weak fourth-order dispersion and its resurgence with stronger values. Our study demonstrates that Akhmediev breathers, under the influence of fourth-order dispersion, possess the capability to generate infinitely many intricate yet coherent patterns in the temporal domain.

Demonstration of a low loss, highly stable and re-useable edge coupler for high heralding efficiency and low g(2)(0) SOI correlated photon pair sources.

We report a stable, low loss method for coupling light from silicon-on-insulator (SOI) photonic chips into optical fibers. The technique is realized using an on-chip tapered waveguide and a cleaved small core optical fiber. The on-chip taper is monolithic and does not require a patterned cladding, thus simplifying the chip fabrication process. The optical fiber segment is composed of a centimeter-long small core fiber (UHNA7) which is spliced to SMF-28 fiber with less than -0.1 dB loss. We observe an overall coupling loss of -0.64 dB with this design. The chip edge and fiber tip can be butt coupled without damaging the on-chip taper or fiber. Friction between the surfaces maintains alignment leading to an observation of ±0.1 dB coupling fluctuation during a ten-day continuous measurement without use of any adhesive. This technique minimizes the potential for generating Raman noise in the fiber, and has good stability compared to coupling strategies based on longer UHNA fibers or fragile lensed fibers. We also applied the edge coupler on a correlated photon pair source and observed a raw coincidence count rate of 1.21 million cps and raw heralding efficiency of 21.3%. We achieved an auto correlation function g H(2)(0) as low as 0.0004 at the low pump power regime.

Validity and reliability of a new clinician-rated tool for freezing of gait severity.

PURPOSE: The Freezing of Gait Severity Tool (FOG Tool) was developed because of limitations in existing assessments. This cross-sectional study investigated its validity and reliability. METHODS: People with Parkinson's disease (PD) were recruited consecutively from clinics. Those who could not walk eight-metres independently (with or without an assistive device), comprehend instructions, or with co-morbidities affecting walking were excluded. Participants completed a set of assessments including the FOG Tool, Timed Up and Go (TUG), and Freezing of Gait Questionnaire. The FOG Tool was repeated and those reporting no medication state change evaluated for test-retest reliability. Validity and reliability were investigated through Spearman's correlations and ICC (two-way, random). McNemar's test was applied to compare the FOG Tool and TUG on the proportion of people with freezing. RESULTS: Thirty-nine participants were recruited [79.5%(n = 31) male; Median(IQR): age-73.0(9.0) years; disease duration-4.0(5.8) years]. Fifteen (38.5%) contributed to test-retest reliability analyses. The FOG Tool demonstrated strongest associations with the Freezing of Gait Questionnaire (ρ = 0.67, 95%CI 0.43-0.83). Test-retest reliability was excellent (ICC = 0.96, 95%CI 0.88-0.99). The FOG Tool had 6.2 times the odds (95%CI 2.4-20.4, p < 0.001) of triggering freezing compared to the TUG. CONCLUSIONS: The FOG Tool appeared adequately valid and reliable in this small sample of people with PD. It was more successful in triggering freezing than the TUG.Implications for RehabilitationThe Freezing of Gait Severity Tool's assessment course is more effective than the commonly-used Timed Up and Go's assessment course for eliciting freezing of gait for clinical evaluation in people with Parkinson's disease.The Freezing of Gait Severity Tool can be considered for scoring freezing of gait severity in people with Parkinson's disease in the clinical setting.

Reliability and variability of physiotherapists scoring freezing of gait through video analysis.

BACKGROUND: The "gold standard" marker for freezing of gait severity is percentage of time spent with freezing observed through video analysis. OBJECTIVE: This study examined inter- and intra-rater reliability and variability of physiotherapists rating freezing of gait severity through video analysis and explored the effects of experience. METHODS: Thirty physiotherapists rated 14 videos of Timed Up and Go performance by people with Parkinson's and gait freezing. Ten videos were unique, while four were repeated. Freezing frequency, total duration, and percentage of time spent with freezing were computed. Reliability and variability were estimated using ICC (2,1) and mean absolute differences. Between-group differences were calculated with the one-way ANOVA. RESULTS: Inter- and intra-rater reliability ranged from moderate to good (ICC: inter-rater frequency = 0.63, duration = 0.78, percentage = 0.50; intra-rater frequency = 0.84, duration = 0.89, percentage = 0.50). Variability for freezing frequency was two episodes. Inter- and intra-rater variability for total freezing duration was 18.8 and 12.3 seconds, respectively. For percentage of time spent with freezing, this was 15.2% and 13.5%. Physiotherapy experience had no effect. CONCLUSION: Physiotherapists demonstrated sufficient reliability, but variability was large enough to cause changes in severity classifications on existing rating scales. Percentage of time spent with freezing was the least reliable marker, supporting the use of freezing frequency or total duration instead.

Scoring festination and gait freezing in people with Parkinson's: The freezing of gait severity tool-revised.

BACKGROUND AND PURPOSE: To improve existing clinical assessments for freezing of gait (FOG) severity, a new clinician-rated tool which integrates the varied types of freezing (FOG Severity Tool-Revised) was developed. This cross-sectional study investigated its validity and reliability. METHODS: People with Parkinson's disease who were able to independently ambulate eight-metres and understand study instructions were consecutively recruited from outpatient clinics of a tertiary hospital. Those with co-morbidities severely affecting gait were excluded. Participants were assessed with the FOG Severity Tool-Revised, three functional performance tests, the FOG Questionnaire, and outcomes measuring anxiety, cognition, and disability. The FOG Severity Tool-Revised was repeated for test-retest reliability. Exploratory factor analysis and Cronbach's alpha were computed for structural validity and internal consistency. Reliability and measurement error were estimated with ICC (two-way, random), standard error of measurement, and smallest detectable change (SDC95 ). Criterion-related and construct validity were calculated with Spearman's correlations. RESULTS: Thirty-nine participants were enrolled [79.5% (n = 31) male; Median (IQR): age-73.0 (9.0) years; disease duration-4.0 (5.8) years], with fifteen (38.5%) who reported no medication state change contributing a second assessment for reliability estimation. The FOG Severity Tool-Revised demonstrated sufficient structural validity and internal consistency (α = 0.89-0.93), and adequate criterion-related validity compared to the FOG Questionnaire (ρ = 0.73, 95% CI 0.54-0.85). Test-retest reliability (ICC = 0.96, 95%CI 0.86-0.99) and random measurement error (%SDC95  = 10.4%) was acceptable in this limited sample. DISCUSSION AND CONCLUSIONS: The FOG Severity Tool-Revised appeared valid in this initial sample of people with Parkinson's. While its psychometric properties remain to be confirmed in a larger sample, it may be considered for use in the clinical setting.

Quiet standing postural control variables in subacute stroke: associations with gait and balance, falls prediction and responsiveness.

PURPOSE: To examine the construct validity, predictive validity and responsiveness of standing centre of pressure variables in subacute stroke. MATERIALS AND METHODS: Seventy-nine ambulatory individuals were assessed before inpatient rehabilitation discharge and three months later. Measures were: gait speed (6-metre walk), dynamic balance (step test), and quiet standing (Wii Balance Board). Centre of pressure speed, amplitude, standard deviation, root mean square, wavelet decomposition, and detrended fluctuation analysis were examined. Falls data were collected over a 12-month period post-discharge. RESULTS: Moderate strength correlations (r = -0.505 to -0.548) with gait speed and step test scores were shown for 3/26 centre of pressure variables (mediolateral speed, low and moderate frequency wavelet). Twenty-two participants fell and the prediction was significant for gait speed and step test (IQR-odds ratio (OR) = 4.00 & 3.21) and 3/26 centre of pressure variables (mediolateral low-frequency wavelet: IQR-OR = 2.71; mediolateral detrended fluctuation analysis: IQR-OR = 3.06; anteroposterior detrended fluctuation analysis: IQR-OR = 2.71). Significant changes over time occurred for gait speed and step test scores and 20/26 centre of pressure variables. CONCLUSIONS: Standing centre of pressure variables have limited validity to reflect dynamic balance and falls risk after stroke. Frequency and complexity measures warrant further exploration.Implications for rehabilitationOur findings indicate that quiet standing centre of pressure variables have limited validity to reflect dynamic balance tasks and predict falls after stroke.The mediolateral and higher frequency variables may be more strongly recommended than the commonly used total centre of pressure speed measure.Measures of signal frequency and complexity may provide insight into postural control mechanisms and how these change over time following stroke.

A topological nonlinear parametric amplifier.

Topological boundary states are well localized eigenstates at the boundary between two different bulk topologies. As long as bulk topology is preserved, the topological boundary mode will endure. Here, we report topological nonlinear parametric amplification of light in a dimerized coupled waveguide system based on the Su-Schrieffer-Heeger model with a domain wall. The good linear transmission properties of the topological waveguide arising from the strong localization of light to the topological boundary is demonstrated through successful high-speed transmission of 30 Gb/s non-return-to-zero and 56 Gb/s pulse amplitude 4-level data. The strong localization of a co-propagating pump and probe to the boundary waveguide is harnessed for efficient, low power optical parametric amplification and wavelength conversion. A nonlinear tuning mechanism is shown to induce chiral symmetry breaking in the topological waveguide, demonstrating a pathway in which Kerr nonlinearities may be applied to tune the topological boundary mode and control the transition to bulk states.

Developing the Freezing of Gait Severity Tool: A Delphi consensus study to determine the content of a clinician-rated assessment for freezing of gait severity.

OBJECTIVES: There is no standardisation of tasks or measures for evaluation of freezing of gait severity in people with Parkinson's disease. This study aimed to develop a clinician-rated tool for freezing of gait severity (i.e. Freezing of Gait Severity Tool), through determining clinicians' ratings of the most important triggering circumstances to be examined and aspects of freezing of gait to be measured. DESIGN: A three-round, web-based Delphi study. PARTICIPANTS: Healthcare professionals, with at least five years' experience in managing freezing of gait in people with Parkinson. MAIN OUTCOME MEASURES: Round 1 required participants (n = 28) to rate items on a 5-point Likert scale, based on priority for inclusion in the Freezing of Gait Severity Tool. In Round 2, participants (n = 18) ranked the items based on priority for inclusion. In Round 3, participants (n = 18) confirmed or rejected the shortlisted items by judging their ability, on a binary scale, to screen for freezing of gait, detect changes in freezing severity, and discriminate between degrees of severity. RESULTS: Participants agreed with the triggering circumstances of turning hesitation, narrow space hesitation, start hesitation, cognitive dual-tasking, and open space hesitation should be assessed; and the aspects of gait freezing to be measured included freezing type, number of freezing episodes during a task, and average duration of freezing episodes. CONCLUSIONS: This study attained a consensus for the items to be included in a clinician-rated tool for freezing of gait severity. Future studies should investigate psychometric properties and clinical feasibility of the Freezing of Gait Severity Tool.

Femoral neck stress fracture and medial tibial stress syndrome following high intensity interval training: A case report and review of literature.

BACKGROUND: Femoral and tibial stress injuries are commonly found in long distance running athletes. Stress fractures have rarely been reported in athletes performing high intensity interval training (HIIT) exercise. The objective of this study was to report a case of a patient who presented with medial tibial stress syndrome and femoral neck stress fracture after performing HIIT exercises. CASE SUMMARY: A 26 year old female presented with bilateral medial tibial pain. She had been performing HIIT exercise for 45 min, five times weekly, for a seven month period. Her tibial pain was gradual in onset, and was now severe and worse on exercise, despite six weeks of rest. Magnetic resonance imaging (MRI) revealed bilateral medial tibial stress syndrome. As she was taking norethisterone for birth control, a dual energy X-ray absorbitometry scan was performed which demonstrated normal bone mineral density of her lumbar spine and femoral neck. She was managed conservatively with analgesia and physiotherapy, but continued to exercise against medical advice. She presented again six months later with severe right hip pain. MRI of her right hip demonstrated an incomplete stress fracture of her subtrochanteric region. Her symptoms resolved with strict rest and physiotherapy. CONCLUSION: HIIT may cause stress injury of the tibia and femur in young individuals.

Optical characterization of deuterated silicon-rich nitride waveguides.

Chemical vapor deposition-based growth techniques allow flexible design of complementary metal-oxide semiconductor (CMOS) compatible materials. Here, we report the deuterated silicon-rich nitride films grown using plasma-enhanced chemical vapor deposition. The linear and nonlinear properties of the films are characterized, and we experimentally confirm that the silicon-rich nitride films grown with SiD4 eliminates Si-H and N-H related absorption. The performance of identical waveguides for films grown with SiH4 and SiD4 are compared demonstrating a 2 dB/cm improvement in line with that observed in literature. Waveguides fabricated on the SRN:D film are further shown to possess a nonlinear parameter of 95 W-1 m-1, with the film exhibiting a linear and nonlinear refractive index of 2.46 and 9.8 [Formula: see text] 10-18 m2W-1 respectively.

Supercontinuum generation in a nonlinear ultra-silicon-rich nitride waveguide.

Supercontinuum generation is demonstrated in a 3-mm-long ultra-silicon-rich nitride (USRN) waveguide by launching 500 fs pulses centered at 1555 nm with a pulse energy of 17 pJ. The generated supercontinuum is experimentally characterized to possess a high spectral coherence, with an average |g12| exceeding 0.90 across the wavelength range of the coherence measurement (1260 nm to 1700 nm). Numerical simulations further indicate a high coherence over the full spectrum. The experimentally measured supercontinuum agrees well with the theoretical simulations based on the generalized nonlinear Schrödinger equation. The generated broadband spectra using 500 fs pulses possessing high spectral coherence provide a promising route for CMOS-compatible light sources for self-referencing applications, metrology, and imaging.

Enhanced photonics devices based on low temperature plasma-deposited dichlorosilane-based ultra-silicon-rich nitride (Si8N).

Ultra-silicon-rich nitride with refractive indices ~ 3 possesses high nonlinear refractive index-100× higher than stoichiometric silicon nitride and presents absence of two-photon absorption, making it attractive to be used in nonlinear integrated optics at telecommunications wavelengths. Despite its excellent nonlinear properties, ultra-silicon-rich nitride photonics devices reported so far still have fairly low quality factors of [Formula: see text], which could be mainly attributed by the material absorption bonds. Here, we report low temperature plasma-deposited dichlorosilane-based ultra-silicon-rich nitride (Si8N) with lower material absorption bonds, and ~ 2.5× higher quality factors compared to ultra-silicon-rich nitride conventionally prepared with silane-based chemistry. This material is found to be highly rich in silicon with refractive indices of ~ 3.12 at telecommunications wavelengths and atomic concentration ratio Si:N of ~ 8:1. The material morphology, surface roughness and binding energies are also investigated. Optically, the material absorption bonds are quantified and show an overall reduction. Ring resonators fabricated exhibit improved intrinsic quality factors [Formula: see text], ~ 2.5× higher compared to conventional silane-based ultra-silicon-rich nitride films. This enhanced quality factor from plasma-deposited dichlorosilane-based ultra-silicon-rich nitride signifies better photonics device performance using these films. A pathway has been opened up for further improved device performance of ultra-silicon-rich nitride photonics devices at material level tailored by choice of different chemistries.

Detection of Freezing of Gait Using Convolutional Neural Networks and Data From Lower Limb Motion Sensors.

Parkinson's disease (PD) is a chronic, non-reversible neurodegenerative disorder, and freezing of gait (FOG) is one of the most disabling symptoms in PD as it is often the leading cause of falls and injuries that drastically reduces patients' quality of life. In order to monitor continuously and objectively PD patients who suffer from FOG and enable the possibility of on-demand cueing assistance, a sensor-based FOG detection solution can help clinicians manage the disease and help patients overcome freezing episodes. Many recent studies have leveraged deep learning models to detect FOG using signals extracted from inertial measurement unit (IMU) devices. Usually, the latent features and patterns of FOG are discovered from either the time or frequency domain. In this study, we investigated the use of the time-frequency domain by applying the Continuous Wavelet Transform to signals from IMUs placed on the lower limbs of 63 PD patients who suffered from FOG. We built convolutional neural networks to detect the FOG occurrences, and employed the Bayesian Optimisation approach to obtain the hyper-parameters. The results showed that the proposed subject-independent model was able to achieve a geometric mean of 90.7% and a F1 score of 91.5%.

A pilot randomized controlled trial examining the benefits of an adjuvant psycho-behavioural intervention in comparison to a health education program, on psychological well-being and freezing-of-gait in patients with Parkinson's disease.

This study investigated the effectiveness of a psycho-behavioural intervention (PBI) for freezing of gait (FOG) management in people with Parkinson's disease, through a double-blind randomized controlled pilot trial conducted with nineteen participants. Though no significant between-group differences were found, PBI was feasible, well-tolerated by participants, and exhibited a trend towards improvement for FOG and depression, thereby warranting further longitudinal investigations.

High spectro-temporal compression on a nonlinear CMOS-chip.

Optical pulses are fundamentally defined by their temporal and spectral properties. The ability to control pulse properties allows practitioners to efficiently leverage them for advanced metrology, high speed optical communications and attosecond science. Here, we report 11× temporal compression of 5.8 ps pulses to 0.55 ps using a low power of 13.3 W. The result is accompanied by a significant increase in the pulse peak power by 9.4×. These results represent the strongest temporal compression demonstrated to date on a complementary metal-oxide-semiconductor (CMOS) chip. In addition, we report the first demonstration of on-chip spectral compression, 3.0× spectral compression of 480 fs pulses, importantly while preserving the pulse energy. The strong compression achieved at low powers harnesses advanced on-chip device design, and the strong nonlinear properties of backend-CMOS compatible ultra-silicon-rich nitride, which possesses absence of two-photon absorption and 500× larger nonlinear parameter than in stoichiometric silicon nitride waveguides. The demonstrated work introduces an important new paradigm for spectro-temporal compression of optical pulses toward turn-key, on-chip integrated systems for all-optical pulse control.

What Factors Influence Clinicians' Use of Technology in Neurorehabilitation? A Multisite Qualitative Study.

OBJECTIVE: Technology is being increasingly used for physical assessment and interventions in health care settings. However, clinical adoption is relatively slow, and the factors affecting use remain underexplored. This study aimed to investigate factors influencing technology use by clinicians working in neurorehabilitation. METHODS: In this qualitative study, 9 physical therapists and 9 occupational therapists (N = 18) were recruited from urban and regional locations in Australia and in Singapore. Three 60-minute focus groups were conducted via video conferencing. Each group comprised 3 physical therapists and 3 occupational therapists working across different neurorehabilitation settings. Participants were asked to discuss which technologies they used in their workplace for physical assessment and treatment and barriers, motivators, and future desires for technology use. Transcripts were analyzed independently using an inductive approach to generate codes and themes. RESULTS: Our results comprised 3 themes and 7 categories. These were encompassed by a single overarching theme, namely "Technology use is influenced by the benefits and challenges of the technology itself, users, and organizational context." Themes showed that technology should promote effective interventions, is preferred if easy to use, and should be dependable. Furthermore, clinical reasoning is important, and users have varying levels of receptivity and confidence in technology use. Also, organizational resources are required, along with supportive cultures and processes, to facilitate technology use. CONCLUSIONS: The themes identified multiple and interlinking factors influencing clinicians' use of technology in neurorehabilitation settings. Clinicians often consider context-specific benefits and challenges when deciding whether to use technology. Although our study found that clinicians generally perceived technology as having a beneficial role in improving health outcomes, there were several challenges raised. Therefore, the characteristics of the technology itself, individual users, and organizational context should be considered. IMPACT: These findings will guide successful technology implementation and future developments.

Paretic and Nonparetic Step Tests Are Noninterchangeable in Stroke: A Prospective Cohort Study.

OBJECTIVE: The step test (ST) is a common clinical assessment of dynamic balance among survivors of stroke. The ST assesses a person's ability to place their paretic (paretic ST) or nonparetic (nonparetic ST) foot rapidly and repeatedly on and off a standardized block while standing. No study has formally explored if the 2 tests are interchangeable. Our study aimed to: (1) differentiate the correlates of paretic and nonparetic ST, and (2) compare their associations with physical function and falls. METHODS: Eighty-one survivors of stroke were consecutively recruited from inpatient rehabilitation units (n = 4) and were assessed within 1 week prior to discharge. In addition to the ST, a handheld dynamometer and computerized posturography were used to measure lower limb muscle strength and standing balance, respectively. Self-selected gait speed and Timed Up and Go test were also assessed as measures of physical function. Falls data were monitored for 12 months post discharge using monthly calendars. Multivariable regression analyses were used to differentiate (1) the correlates of paretic and nonparetic STs, and (2) their associations with physical function and falls. RESULTS: The median score for the paretic and nonparetic STs were 8 and 9 steps, respectively. Paretic ankle plantar-flexor and dorsiflexor strength were the strongest correlates of nonparetic ST, whereas both paretic ankle and knee extensor strength were the strongest correlates of paretic ST. In multivariable analyses adjusting for each other, both STs were independently associated with gait speed and Timed Up and Go scores. Paretic ST (odds ratio = 0.37; 95% CI = 0.22 to 0.62) was a stronger predictor than nonparetic ST (odds ratio = 0.51; 95% CI = 0.34 to 0.78) in predicting future falls. CONCLUSION: This study confirmed that the paretic and nonparetic STs are noninterchangeable. ST scores should be assessed separately to achieve a more complete interpretation. IMPACT: To our knowledge, this study is the first to objectively evaluate the similarities and differences between paretic and nonparetic STs. This information may refine the use and interpretation of the 2 STs for survivors of stroke.

Measurement Properties of Assessments of Freezing of Gait Severity in People With Parkinson Disease: A COSMIN Review.

OBJECTIVE: Parkinson disease (PD) is the second-most common neurodegenerative condition worldwide. Approximately 50% of people with PD experience freezing of gait, a motor symptom associated with falls, disability, and poorer quality of life. Accurate assessment of freezing of gait severity is important for guiding management. The aim of this systematic review was to determine the measurement properties of subjective and objective clinical assessments of freezing of gait severity using the COSMIN methodology to facilitate better outcome measure selection. METHODS: Three databases (MEDLINE, EMBASE, and CINAHL) were searched. The COSMIN Risk of Bias checklist was used for evaluating quality of included studies. Data on measurement properties were extracted. Where possible, meta-analysis was performed. RESULTS: Nineteen studies investigating measurement properties of 7 outcome measures (patient-reported outcome measures, n = 3; objective assessment tools, n = 4) were included. Ten studies evaluated the Freezing of Gait Questionnaire. Based on COSMIN criteria, the best performing outcome measures were the Freezing of Gait Questionnaire and the Dynamic Parkinson Gait Scale. Both outcome measures demonstrated sufficient structural validity, internal consistency, reliability, construct validity, and responsiveness. The Freezing of Gait Questionnaire was supported with mostly moderate to high quality of evidence, but the evidence for the Dynamic Parkinson Gait Scale was of low quality due to inadequate sample size. CONCLUSIONS: Content validity and measurement invariance remain unknown for all outcome measures. The Freezing of Gait Questionnaire is the best measure currently available. Further external validation and reliability studies would strengthen the evidence to support the use of the Dynamic Parkinson Gait Scale. IMPACT: Awareness of limitations of outcome measures facilitates better selection. Without evidence for content validity and measurement invariance, clinicians should consider if their chosen test accurately measures freezing of gait severity and whether it can be applied in populations different to the original study's population. LAY SUMMARY: Accurately assessing freezing of gait severity is important for guiding management of this disabling symptom. The best clinical assessment currently available is one that relies on the self-report of patients.

Convolutional Neural Network for Freezing of Gait Detection Leveraging the Continuous Wavelet Transform on Lower Extremities Wearable Sensors Data.

Freezing of Gait is the most disabling gait disturbance in Parkinson's disease. For the past decade, there has been a growing interest in applying machine learning and deep learning models to wearable sensor data to detect Freezing of Gait episodes. In our study, we recruited sixty-seven Parkinson's disease patients who have been suffering from Freezing of Gait, and conducted two clinical assessments while the patients wore two wireless Inertial Measurement Units on their ankles. We converted the recorded time-series sensor data into continuous wavelet transform scalograms and trained a Convolutional Neural Network to detect the freezing episodes. The proposed model achieved a generalisation accuracy of 89.2% and a geometric mean of 88.8%.

Exploring post acute rehabilitation service use and outcomes for working age stroke survivors (≤65 years) in Australia, UK and South East Asia: data from the international AVERT trial.

OBJECTIVES: Information about younger people of working age (≤65 years), their post stroke outcomes and rehabilitation pathways can highlight areas for further research and service change. This paper describes: (1) baseline demographics; (2) post acute rehabilitation pathways; and (3) 12-month outcomes; disability, mobility, depression, quality of life, informal care and return to work of working age people across three geographic regions (Australasia (AUS), South East (SE) Asia and UK). DESIGN: This post hoc descriptive exploration of data from the large international very early rehabilitation trial (A Very Early Rehabilitation Trial (AVERT)) examined the four common post acute rehabilitation pathways (inpatient rehabilitation, home with community rehabilitation, inpatient rehabilitation then community rehabilitation and home with no rehabilitation) experienced by participants in the 3 months post stroke and describes their 12-month outcomes. SETTING: Hospital stroke units in AUS, UK and SE Asia. PARTICIPANTS: Patients who had an acute stroke recruited within 24 hours who were ≤65 years. RESULTS: 668 participants were ≤65 years; 99% lived independently, and 88% no disability (modified Rankin Score (mRS)=0) prior to stroke. We had complete data for 12-month outcomes for n=631 (94%). The proportion receiving inpatient rehabilitation was higher in AUS than other regions (AUS 52%; UK 25%; SE Asia 23%), whereas the UK had higher community rehabilitation (UK 65%; AUS 61%; SE Asia 39%). At 12 months, 70% had no or little disability (mRS 0-2), 44% were depressed, 28% rated quality of life as poor or worse than death. For those working prior to stroke (n=228), only 57% had returned to work. A noteworthy number of working age survivors received no rehabilitation services within 3 months post stroke. CONCLUSIONS: There was considerable variation in rehabilitation pathways and post acute service use across the three regions. At 12 months, there were high rates of depression, poor quality of life and low rates of return to work. TRIAL REGISTRATION NUMBER: Australian New Zealand Clinical Trials Registry (ACTRN12606000185561).