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Optics Express May 2024Tin diselenide (SnSe), a layered transition metal dichalcogenide (TMDC), stands out among other TMDCs for its extraordinary photoactive ability and low thermal...
Tin diselenide (SnSe), a layered transition metal dichalcogenide (TMDC), stands out among other TMDCs for its extraordinary photoactive ability and low thermal conductivity. Consequently, it has stimulated many influential researches on photodetectors, ultrafast pulse shaping, thermoelectric devices, etc. However, the carrier mobility in SnSe, as determined experimentally, remains limited to tens of cmVs. This limitation poses a challenge for achieving high-performance SnSe-based devices. Theoretical calculations, on the other hand, predict that the carrier mobility in SnSe can reach hundreds of cmVs, approximately one order of magnitude higher than experimental value. Interestingly, the carrier mobility could be underestimated significantly in long-range transportation measurements due to the presence of defects and boundary scattering effects. To address this discrepancy, we employ optic pump terahertz probe spectroscopy to access the photoinduced dynamical THz photoconductivity of SnSe. Our findings reveal that the intrinsic carrier mobility in conventional SnSe single crystal is remarkably high, reaching 353.2 ± 37.7 cmVs, consistent with the theoretical prediction. Additionally, dynamical THz photoconductivity measurements reveal that the SnSe crystal containing rich defects efficiently capture photoinduced conduction-band electrons and valence-band holes with time constants of ∼20 and ∼200 ps, respectively. Meanwhile, we observe an impulsively stimulated Raman scattering at 0.60 THz. Our study not only demonstrates ultrafast THz spectroscopy as a reliable method for determining intrinsic carrier mobility and detection of low frequency coherent Raman mode in materials but also provides valuable reference for the future application of high-performance SnSe-based devices.
PubMed: 38858943
DOI: 10.1364/OE.523383 -
Child's Nervous System : ChNS :... Jun 2024Giant extradural thoracic schwannomas are very rare tumors in the pediatric age group and often occur together with neurofibromatosis. Giant schwannomas span across more...
INTRODUCTION
Giant extradural thoracic schwannomas are very rare tumors in the pediatric age group and often occur together with neurofibromatosis. Giant schwannomas span across more than two vertebral segments and have an extraspinal extension of over 2.5 cm. In this case, we report on a 5-year-old boy with a purely extradural giant schwannoma without accompanying neurofibromatosis.
CLINICAL PRESENTATION
A 5-year-old male patient was admitted to the orthopedics and traumatology outpatient clinic with complaints of difficulty in walking following waist and left leg pain after falling from a chair. Contrast-enhanced spinal MRI and cranial MRI showed an extradural spinal lesion measuring 22 × 18 × 35 mm that pushed the spinal cord to the right at the T10-12 level and extended into the left foramen at the T11-12 level. The patient was operated. The tumor was removed completely by performing bilateral laminoplasty at the T10-11-12 levels. Histopathology result reported schwannoma.
CONCLUSION
Giant schwannomas are slow-growing tumors that rarely occur in childhood. In these patients, spinal traumas can lead to serious neurological deficits. Early diagnosis and successful surgery can prevent permanent neurological damage.
PubMed: 38858275
DOI: 10.1007/s00381-024-06494-6 -
Journal of Transport & Health Jan 2024Older drivers now expect to drive longer than previous cohorts and will make up about 25% of licensed U.S. drivers by 2050. Identifying early predictors of nighttime...
INTRODUCTION
Older drivers now expect to drive longer than previous cohorts and will make up about 25% of licensed U.S. drivers by 2050. Identifying early predictors of nighttime driving difficulty, a precursor to driving retirement, can inform screening procedures and timely linkage to interventions supporting driving or transitioning to driving cessation.
METHODS
We examined self-reported physical and mental health baseline predictors of greater nighttime driving difficulty in five and ten years using weighted multivariate logistic analyses of 2261 drivers, aged 57 to 85, from the National Social Life, Health, and Aging Project (NSHAP). Transition matrix models describe probabilities of having greater, lesser, or the same nighttime driving difficulty after five years based on baseline driving conditions and the significant logistic model factors. We built a transition matrix tool that offers users the ability to calculate expected probabilities of change in nighttime driving difficulty based on the identified salient factors.
RESULTS
Five-year predictors of greater nighttime driving difficulty included perceived poor physical health (OR = 3.75), limitations to activities of daily living (ADLs; OR = 1.97), and clinical levels of depressive and anxiety symptoms (OR = 1.63; OR = 1.71). Excellent physical health (OR = 0.52), mental health (OR = 0.60), and any frequency of physical activity compared to 'never' were protective (OR = 0.37-0.51). Physical health, walking pain, and limitations to ADLs were predictive at ten-years. Transition models showed physical health and anxiety were most indicative of greater nighttime driving difficulty at 5-years for those reporting no difficulty at baseline, but limitations to ADLs were more predictive otherwise.
CONCLUSIONS
Lay practitioners could capitalize on the use of self-report screening measures to identify older adults who may experience near-term nighttime driving difficulty. Earlier identification may better guide long-term driving retirement planning or engagement in appropriate health interventions. The transition matrix modeling tool is freely available to facilitate development and validation of related measures.
PubMed: 38855420
DOI: 10.1016/j.jth.2023.101724 -
Neurobiology of Aging May 2024We determined beta-band intermuscular (IMC) and corticomuscular coherence (CMC) as a function of age and walking balance difficulty. Younger (n=14, 23y) and older...
We determined beta-band intermuscular (IMC) and corticomuscular coherence (CMC) as a function of age and walking balance difficulty. Younger (n=14, 23y) and older individuals (n=19, 71y) walked 13 m overground, on a 6-cm-wide ribbon overground, and on a 6-cm-wide (5-cm-high) beam. Walking distance as a proxy for walking balance and speed were computed. CMC was estimated between electroencephalographic signal at Cz electrode and surface electromyographic signals of seven leg muscles, while IMC was calculated in four pairs of leg muscles, during stance and swing gait phases. With increasing difficulty, walking balance decreased in old individuals and speed decreased gradually independent of age. Beam walking increased IMC, while age increased IMC in proximal muscle pairs, and decreased IMC in distal muscle pairs. Age and difficulty increased CMC independent of gait phases. Concluding, CMC and IMC increased with walking balance difficulty and age, except for distal muscle pairs, which had lower IMC with age. These findings suggest an age-related increase in corticospinal involvement in the neural control of walking balance. DATA AVAILABILITY: The datasets used in this study are available from the corresponding author upon reasonable request.
PubMed: 38850592
DOI: 10.1016/j.neurobiolaging.2024.05.004 -
Medicine Jun 2024This study aimed to investigate the different impacts of sensorial and mobility frailty on overall and domain-specific cognitive function. Further, the independent... (Observational Study)
Observational Study
This study aimed to investigate the different impacts of sensorial and mobility frailty on overall and domain-specific cognitive function. Further, the independent associations between other intricate capacity (IC) dimensions, including vitality and psychological dimensions, and overall and domain-specific cognitive function were investigated. A total of 429 participants (mean age, 72.91 ± 7.014 years; 57.30% female) underwent IC capacity assessment. Other covariates, such as demographics, health-related variables were also assessed. Overall or domain-specific cognitive impairment was used as a dependent variable in logistic regression analyses adjusted for demographic, health-related, and psychosocial confounders. After adjustment for demographic, health-related, and psychosocial confounders, individuals with sensorial frailty (odds ratio [OR] = 0.435; 95% confidence interval [CI] = 0.236-0.801; P = .008) had a significantly lower risk of mild cognitive impairment (MCI), marginally low delayed memory impairment (OR = 0.601, 95% CI = 0.347-1.040; P = .069), and language impairment (OR = 0.534, 95% CI = 0.305-0.936; OR = 0.318, P = .029; OR = 0.318,95% CI = 0.173-0.586; P < .001) by Boston naming and animal fluency tests than did those with both sensorial and mobility frailty or mobility frailty only. Depressive symptoms had a significant negative influence on executive function. Cardiovascular disease and non-skin malignancy were independent determinants of MCI, and diabetes mellitus was independently associated with processing speed, attention, and executive function. Sensorial and mobility frailty were independent risk factors for cognitive impairment. Mobility frailty had a greater negative influence on the overall cognitive function and memory and language function than did sensorial frailty. The reserve decline in the psychological dimension of IC and chronic diseases also had a significant adverse influence on overall and domain-specific cognition function.
Topics: Humans; Female; Male; Aged; Cognitive Dysfunction; Independent Living; China; Cognition; Frailty; Frail Elderly; Aged, 80 and over; Geriatric Assessment; Cross-Sectional Studies; Mobility Limitation; East Asian People
PubMed: 38847667
DOI: 10.1097/MD.0000000000038500 -
Annals of Medicine and Surgery (2012) Jun 2024Intramedullary nondysraphic spinal lipomas are extremely rare among primary spinal cord tumors. These patients present with nonspecific sensory symptoms followed by...
INTRODUCTION
Intramedullary nondysraphic spinal lipomas are extremely rare among primary spinal cord tumors. These patients present with nonspecific sensory symptoms followed by deterioration of motor symptoms. As the safety margins for neurological preservation are thin, meticulously locating the extent of the tumor and choosing the resection modalities is essential.
CASE REPORT
The authors report a rare case of a 35-year-old male who presented with progressive difficulty in walking for 6 months associated with numbness and tingling sensation in the bilateral upper and lower limbs. He was diagnosed with nondysraphic intramedullary cervicothoracic lipoma and underwent subtotal resection of the tumor.
CONCLUSION
Nondysraphic intramedullary spinal cord lipomas are rare and may present as nonspecific neurological symptoms. Hence, they should be considered differentials of intramedullary spinal cord tumors. Surgery appears to be the mainstay of treatment.
PubMed: 38846861
DOI: 10.1097/MS9.0000000000002060 -
European Spine Journal : Official... Jun 2024The purpose of the present study was to investigate the association between quantitatively assessed trunk extensor strength and gait-induced back pain (GIBP) in patients...
PURPOSE
The purpose of the present study was to investigate the association between quantitatively assessed trunk extensor strength and gait-induced back pain (GIBP) in patients with adult spinal deformity (ASD).
METHODS
Ninety-five patients with ASD aged ≥ 50 years who were admitted to our hospital between April 2018 and March 2023 were included in the study. GIBP was evaluated through a 6-minute walking test (6MWT), with GIBP being defined as the occurrence of back pain during the evaluation and inability to complete the test. The patients were divided into three groups: difficulty completing the 6MWT (Group 1), ability to complete the 6MWT with breaks (Group 2), and ability to complete the 6MWT without taking a break (Group 3). The main independent variable was trunk extensor strength, which was measured using a hand-held dynamometer. Ordered logistic regression analysis was conducted to assess the association between GIBP and trunk extensor strength while adjusting for basic characteristics and radiographic parameters as covariates.
RESULTS
The numbers of patients with ASD included in each group were; 27 in Group 1 (28.4%), 31 in Group 2 (32.6%), and 37 in Group 3 (39.0%). An ordered logistic regression analysis adjusted for basic characteristics and radiographic parameters, trunk extensor strength was significantly associated with GIBP (odds ratios, 1.128; 95% confidence intervals, 1.025-1.242).
CONCLUSIONS
The results of the present study strongly indicate that trunk extensor strength is a valuable factor associated with GIBP in patients with ASD.
PubMed: 38844588
DOI: 10.1007/s00586-024-08348-w -
Neurological Sciences : Official... Jun 2024To systematically review and conduct a meta-analysis to evaluate the safety and efficacy of the unilateral focused ultrasound (FUS) pallidotomy on motor complications in... (Review)
Review
To systematically review and conduct a meta-analysis to evaluate the safety and efficacy of the unilateral focused ultrasound (FUS) pallidotomy on motor complications in Parkinson's disease (PD) patients. A comprehensive search strategy was implemented through August 15, 2023, and updated on February 13, 2024, across six databases, identifying studies relevant to unilateral focused ultrasound pallidotomy and PD. Eligibility criteria included observational studies, clinical trials, and case series reporting on the impact of the intervention on motor complications in PD patients. The screening and data extraction were done by two independent reviewers. Risk of bias assessment utilized appropriate tools for different study designs. Statistical analysis involved narrative synthesis and meta-analysis. Subgroup analyses and leave-one-out analyses were performed. Five studies were included in our study, involving 112 PD patients undergoing FUS pallidotomy. UPDRS-II analysis revealed a significant improvement from baseline (mean difference (MD): -3.205, 95% CI: -4.501, -1.909, P < 0.001). UPDRS-III overall change was significant (MD: -10.177, 95% CI: [-12.748, -7.606], P < 0.001). UPDRS-IV showed a significant change from baseline (MD: -5.069, 95% CI: [-5.915, -4.224], P < 0.001). UDysRS demonstrated a significant overall improvement (MD: -18.895, 95% CI: [-26.973, -10.818], P < 0.001). The effect of FUS pallidotomy on motor complications in PD patients was effective, with a significant decrease in the UPDRS and UDysRS, reflecting improvement. The incidence of adverse events (headaches, pin-site pain, difficulty walking, and sonication-related head pain) of the FUS pallidotomy was not statistically significant, indicating its safety.
PubMed: 38842771
DOI: 10.1007/s10072-024-07617-2 -
JMIR Aging Jun 2024Walking is important for maintaining physical and mental well-being in aged residential care (ARC). Walking behaviors are not well characterized in ARC due to... (Comparative Study)
Comparative Study Randomized Controlled Trial
Characterizing Walking Behaviors in Aged Residential Care Using Accelerometry, With Comparison Across Care Levels, Cognitive Status, and Physical Function: Cross-Sectional Study.
BACKGROUND
Walking is important for maintaining physical and mental well-being in aged residential care (ARC). Walking behaviors are not well characterized in ARC due to inconsistencies in assessment methods and metrics as well as limited research regarding the impact of care environment, cognition, or physical function on these behaviors. It is recommended that walking behaviors in ARC are assessed using validated digital methods that can capture low volumes of walking activity.
OBJECTIVE
This study aims to characterize and compare accelerometry-derived walking behaviors in ARC residents across different care levels, cognitive abilities, and physical capacities.
METHODS
A total of 306 ARC residents were recruited from the Staying UpRight randomized controlled trial from 3 care levels: rest home (n=164), hospital (n=117), and dementia care (n=25). Participants' cognitive status was classified as mild (n=87), moderate (n=128), or severe impairment (n=61); physical function was classified as high-moderate (n=74) and low-very low (n=222) using the Montreal Cognitive Assessment and the Short Physical Performance Battery cutoff scores, respectively. To assess walking, participants wore an accelerometer (Axivity AX3; dimensions: 23×32.5×7.6 mm; weight: 11 g; sampling rate: 100 Hz; range: ±8 g; and memory: 512 MB) on their lower back for 7 days. Outcomes included volume (ie, daily time spent walking, steps, and bouts), pattern (ie, mean walking bout duration and alpha), and variability (of bout length) of walking. Analysis of covariance was used to assess differences in walking behaviors between groups categorized by level of care, cognition, or physical function while controlling for age and sex. Tukey honest significant difference tests for multiple comparisons were used to determine where significant differences occurred. The effect sizes of group differences were calculated using Hedges g (0.2-0.4: small, 0.5-0.7: medium, and 0.8: large).
RESULTS
Dementia care residents showed greater volumes of walking (P<.001; Hedges g=1.0-2.0), with longer (P<.001; Hedges g=0.7-0.8), more variable (P=.008 vs hospital; P<.001 vs rest home; Hedges g=0.6-0.9) bouts compared to other care levels with a lower alpha score (vs hospital: P<.001; Hedges g=0.9, vs rest home: P=.004; Hedges g=0.8). Residents with severe cognitive impairment took longer (P<.001; Hedges g=0.5-0.6), more variable (P<.001; Hedges g=0.4-0.6) bouts, compared to those with mild and moderate cognitive impairment. Residents with low-very low physical function had lower walking volumes (total walk time and bouts per day: P<.001; steps per day: P=.005; Hedges g=0.4-0.5) and higher variability (P=.04; Hedges g=0.2) compared to those with high-moderate capacity.
CONCLUSIONS
ARC residents across different levels of care, cognition, and physical function demonstrate different walking behaviors. However, ARC residents often present with varying levels of both cognitive and physical abilities, reflecting their complex multimorbid nature, which should be considered in further work. This work has demonstrated the importance of considering a nuanced framework of digital outcomes relating to volume, pattern, and variability of walking behaviors among ARC residents.
Topics: Humans; Accelerometry; Male; Female; Cross-Sectional Studies; Walking; Aged, 80 and over; Cognition; Aged; Homes for the Aged
PubMed: 38842168
DOI: 10.2196/53020 -
Arthroscopy Techniques May 2024Checkrein deformity is rare and involves entrapment or fixed tethering of the flexor hallucis longus (FHL) in the posterior foot, just proximal to the flexor retinaculum...
Checkrein deformity is rare and involves entrapment or fixed tethering of the flexor hallucis longus (FHL) in the posterior foot, just proximal to the flexor retinaculum of the ankle, and causes the "constant length phenomenon" of FHL. The clinical presentation is a dynamic flexion deformity of the great toe characterized by flexion contracture of the interphalangeal joint with mild extension contracture of the metatarsophalangeal joint, causing difficulty in walking since in the stance phase of gait, the hallux is forced into plantar flexion and impinges onto the ground. Because the FHL tendon has some interconnection to the tendons of the flexor digitorum longus at the master knot of Henry, deformities of the second and third toes are sometimes seen. There is no standard surgical treatment for checkrein deformity. Surgical release of the FHL muscle or release/lengthening of the FHL tendon has been proposed. The purpose of this Technical Note is to report the endoscopic release of the FHL tendon at the posterior ankle for management of checkrein deformity of the great toe, second toe, and third toe.
PubMed: 38835445
DOI: 10.1016/j.eats.2024.102936