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Vertical and torsional ocular misalignment can occur from mild traumatic brain injury or inner ear pathology, which may vary depending on head position. Here, we evaluate differences in a behavioral measure of binocular alignment in both upright and supine head position. Ocular perception of vertical and torsional alignment was measured using the torsional and vertical alignment nulling (TAN, VAN) task in N = 52 veterans with dizziness (N = 38 with traumatic brain injury), N = 41 civilians with vestibular schwannoma resection (UVD), and N = 33 healthy controls for both positions. The interquartile range within each group, regardless of head position, was greater for torsional compared to vertical misalignment. We use generalized estimating equations to compare average TAN (torsional) scores and VAN (vertical) scores between groups and test position. Compared to the healthy controls, TAN was significantly increased by + 0.4186° in veterans (P = 0.030) and by + 0.5747° in UVD (P = 0.010), but there was no difference with head position. For VAN, no difference was found between the three groups, but the misalignment did worsen by 0.0888° (P = 0.0070) as the head position moved from upright to supine. Head position had negligible effects on this behavioral measure of vertical and torsional binocular misalignment, and torsional misalignments were worse than controls in both veterans with dizziness and patients with vestibular nerve resection although neither reported torsional diplopia. Our data suggests that the tolerance for roll misalignment may be abnormally large in patients with dizziness. Alternatively, perceptual roll misalignments may be a manifest cause for dizziness, and therefore a useful proxy for distinguishing differences in putative otolith function in veterans with dizziness.

Crossing the blood–brain barrier is a crucial, rate-limiting step of brain metastasis. Understanding of the mechanisms of cancer cell extravasation from brain microcapillaries is limited as the underlying cellular and molecular processes cannot be adequately investigated using in vitro models and endpoint in vivo experiments. Using ultrastructural and functional imaging, we demonstrate that dynamic changes of activated brain microcapillaries promote the mandatory first steps of brain colonization. Successful extravasation of arrested cancer cells occurred when adjacent capillary endothelial cells (EC) entered into a distinct remodeling process. After extravasation, capillary loops were formed, which was characteristic of aggressive metastatic growth. Upon cancer cell arrest in brain microcapillaries, matrix-metalloprotease 9 (MMP9) was expressed. Inhibition of MMP2/9 and genetic perturbation of MMP9 in cancer cells, but not the host, reduced EC projections, extravasation, and brain metastasis outgrowth. These findings establish an active role of ECs in the process of cancer cell extravasation, facilitated by cross-talk between the two cell types. This extends our understanding of how host cells can contribute to brain metastasis formation and how to prevent it.Significance:Tracking single extravasating cancer cells using multimodal correlative microscopy uncovers a brain seeding mechanism involving endothelial remodeling driven by cancer cell–derived MMP9, which might enable the development of approaches to prevent brain metastasis.See related commentary by McCarty, p. 1167

Supplementary Figures and Figure legends, Supplementary Video legends and supplementary materials and methods

A variant of benign paroxysmal positional vertigo (BPPV) involves the subjective report of vertigo without the coinciding nystagmus. This presentation includes truncal retropulsion when sitting up from the ipsilesional provocative test (ie, Dix-Hallpike), which we term type 2 BPPV. The primary objective of this study is to prospectively determine the prevalence and describe the clinical course of type 2 BPPV. We offer a theoretical explanation for the absence of nystagmus.Prospective, observational study carried out in 2 tertiary hospitals. One hundred eighty patients (134 women, 46 men) met the inclusion criteria and were included between January 10, 2018, and October 30, 2019. Efficacy of physical therapy maneuvers was determined at 1-week follow-up. Three-dimensional reconstructions of the planes of the semicircular canal cupula from histological preparations are offered as evidence for the theoretical explanation.One-third of the patients met the criteria for type 2 BPPV; the remainder had typical posterior or horizontal semicircular canal involvement. Symptoms from type 2 BPPV were longer in duration yet responded favorably to physical therapy maneuvers. Upon repeat testing, 19 patients treated for posterior canalithiasis developed a slight, persistent positional downbeat nystagmus in the Dix-Hallpike position that we propose as evidence the otoconia entered the short arm of the posterior semicircular canal.Our data and 3-dimensional rendering suggest the report of vertigo, yet absent nystagmus in type 2 BPPV is from otoconia aligning with the gravitoinertial vector during provocative testing that precludes cupular stimulation. Type 2 BPPV appears to be a common and treatable form of vertigo.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1 available at: http://links.lww.com/JNPT/A372).

In this article, the impact of different hydrogen configurations and their evolution on the extent and kinetics of light- and elevated-temperature-induced degradation (LeTID) is investigated in float-zone silicon via charge carrier lifetime measurements, low-temperature Fourier-transform infrared spectroscopy, and four-point-probe resistance measurements. Degradation conditions were light soaking at 77 °C and 1 sun-equivalent illumination intensity and dark anneal at 175 °C. The initial configuration of hydrogen is manipulated by varying the wafer thickness, the cooling ramp of the fast-firing process, and the dopant type (B- or P-doped). We find lower hydrogen concentrations in thinner samples and samples with a slower cooling ramp. This suggests that hydrogen diffuses out of the sample during the cool-down, which strongly affects the final concentration of hydrogen molecules H 2 , and to a smaller degree the concentration of boron-hydrogen (BH) pairs. A regeneration of potential LeTID defects and a presumed LeTID degradation during dark annealing is found in n-type Si. In p-type Si, the LeTID extent was found to scale with H 2 , suggesting a direct link between both. The temporal evolution of BH pairs, LeTID degradation/regeneration, and surface degradation depends on wafer thickness and the cooling ramp of the fast-firing process. Based upon these findings, we formulate a theory of the hydrogen-related mechanism behind LeTID: Hydrogen originating from H 2 moves between different temporary traps. First, hydrogen binds to LeTID precursors and acceptor atoms in the silicon bulk, later moving toward the surface. This leads first to the LeTID degradation and regeneration and then to the degradation of surface passivation.

Crossing the blood–brain barrier is a crucial, rate-limiting step of brain metastasis. Understanding of the mechanisms of cancer cell extravasation from brain microcapillaries is limited as the underlying cellular and molecular processes cannot be adequately investigated using in vitro models and endpoint in vivo experiments. Using ultrastructural and functional imaging, we demonstrate that dynamic changes of activated brain microcapillaries promote the mandatory first steps of brain colonization. Successful extravasation of arrested cancer cells occurred when adjacent capillary endothelial cells (EC) entered into a distinct remodeling process. After extravasation, capillary loops were formed, which was characteristic of aggressive metastatic growth. Upon cancer cell arrest in brain microcapillaries, matrix-metalloprotease 9 (MMP9) was expressed. Inhibition of MMP2/9 and genetic perturbation of MMP9 in cancer cells, but not the host, reduced EC projections, extravasation, and brain metastasis outgrowth. These findings establish an active role of ECs in the process of cancer cell extravasation, facilitated by cross-talk between the two cell types. This extends our understanding of how host cells can contribute to brain metastasis formation and how to prevent it. Significance: Tracking single extravasating cancer cells using multimodal correlative microscopy uncovers a brain seeding mechanism involving endothelial remodeling driven by cancer cell–derived MMP9, which might enable the development of approaches to prevent brain metastasis. See related commentary by McCarty, p. 1167

Background Balance stabilization exercises are often prescribed to facilitate compensation in individuals with vestibular schwannoma (VS). However, both the assessment and prescription of these exercises are reliant on clinical observations and expert opinion rather than on quantitative evidence. The aim of this study was to quantify head motion kinematics in individuals with vestibular loss while they performed commonly prescribed balance stability exercises. Methods Using inertial measurement units, head movements of individuals with vestibular schwannoma were measured before and after surgical deafferentation and compared with age-matched controls. Results We found that individuals with vestibular schwannoma experienced more variable head motion compared to healthy controls both pre- and postoperatively, particularly in absence of visual input, but that there was little difference between preoperative and postoperative kinematic measurements for our vestibular schwannoma group. We further found correlations between head motion kinematic measures during balance exercises, performed in the absence of visual input, and multiple clinical measurements for preoperative VS subjects. Subjects with higher head motion variability also had worse DVA scores, moved more slowly during the Timed up and Go and gait speed tests, and had lower scores on the functional gait assessment. In contrast, we did not find strong correlations between clinical measures and postoperative head kinematics for the same VS subjects. Conclusions Our data suggest that further development of such metrics based on the quantification of head motion has merit for the assessment and prescription of balance exercises, as demonstrated by the calculation of a “kinematic score” for identifying the most informative balance exercise (i.e., “Standing on foam eyes closed”).

Objective To examine the effectiveness of event notification service (ENS) alerts on health care delivery processes and outcomes for older adults. Materials and methods We deployed ENS alerts in 2 Veterans Affairs (VA) medical centers using regional health information exchange (HIE) networks from March 2016 to December 2019. Alerts targeted VA-based primary care teams when older patients (aged 65+ years) were hospitalized or attended emergency departments (ED) outside the VA system. We employed a concurrent cohort study to compare postdischarge outcomes between patients whose providers received ENS alerts and those that did not (usual care). Outcome measures included: timely follow-up postdischarge (actual phone call within 7 days or an in-person primary care visit within 30 days) and all-cause inpatient or ED readmission within 30 days. Generalized linear mixed models, accounting for clustering by primary care team, were used to compare outcomes between groups. Results Compared to usual care, veterans whose primary care team received notification of non-VA acute care encounters were 4 times more likely to have phone contact within 7 days (AOR = 4.10, P Discussion ENS was associated with increased timely follow-up following non-VA acute care events, but there was no associated change in 30-day readmission rates. Optimization of ENS processes may be required to scale use and impact across health systems. Conclusion Given the importance of ENS to the VA and other health systems, this study provides guidance for future research on ENS for improving care coordination and population outcomes. Trial Registration ClinicalTrials.gov NCT02689076. “Regional Data Exchange to Improve Care for Veterans After Non-VA Hospitalization.” Registered February 23, 2016.

Diffuse gliomas are primary brain tumors associated with a poor prognosis. Cellular and molecular mechanisms driving the invasive growth patterns and therapeutic resistance are incompletely understood. The emerging field of cancer neuroscience offers a novel approach to study these brain tumors in the context of their intricate interactions with the nervous system employing and combining methodological toolsets from neuroscience and oncology. Increasing evidence has shown how neurodevelopmental and neuronal-like mechanisms are hijacked leading to the discovery of multicellular brain tumor networks. Here, we review how gap junction-coupled tumor-tumor-astrocyte networks, as well as synaptic and paracrine neuron-tumor networks drive glioma progression. Molecular mechanisms of these malignant, homo- and heterotypic networks, and their complex interplay are reviewed. Lastly, potential clinical-translational implications and resulting therapeutic strategies are discussed.

By utilizing the quadratic dependency of the interferometry phase on time, the Hannover Very Long Baseline Atom Interferometer facility (VLBAI) aims for sub nm/s$^2$ gravity measurement sensitivity. With its 10 m vertical baseline, VLBAI offers promising prospects in testing fundamental physics at the interface between quantum mechanics and general relativity. Here we discuss the challenges imposed on controlling VLBAI's magnetic and gravitational environment and report on their effect on the device's accuracy. Within the inner 8 m of the magnetic shield, residual magnetic field gradients expect to cause a bias acceleration of only 6$\times$10$^{-14}$ m/s$^2$ while we evaluate the bias shift due to the facility's non-linear gravity gradient to 2.6 nm/s$^2$. The model allows the VLBAI facility to be a reference to other mobile devices for calibration purposes with an uncertainty below the 10 nm/s$^2$ level., Presented at the Ninth Meeting on CPT and Lorentz Symmetry, Bloomington, Indiana, May 17-26, 2022

Background People with multiple sclerosis (PwMS) frequently experience dizziness and imbalance that may be caused by central vestibular system dysfunction. Vestibular rehabilitation may offer an approach for improving dysfunction in these people. Objective To test the efficacy of a gaze and postural stability (GPS) retraining intervention compared to a strength and endurance (SAE) intervention in PwMS. Methods About 41 PwMS, with complaints of dizziness or history of falls, were randomized to either the GPS or SAE groups. Following randomization participants completed 6-weeks of 3×/week progressive training, delivered one-on-one by a provider. Following intervention, testing was performed at the primary (6-weeks) and secondary time point (10-weeks). A restricted maximum likelihood estimation mixed effects model was used to examine changes in the primary outcome of the Dizziness Handicap Inventory (DHI) between the 2 groups at the primary and secondary time point. Similar models were used to explore secondary outcomes between groups at both timepoints. Results Thirty-five people completed the study (17 GPS; 18 SAE). The change in the DHI at the primary time point was not statistically different between the GPS and SAE groups (mean difference = 2.33 [95% CI −9.18, 12.85]). However, both groups demonstrated significant improvement from baseline to 6-weeks (GPS −8.73; SAE −7.31). Similar results were observed for secondary outcomes and at the secondary timepoint. Conclusions In this sample of PwMS with complaints of dizziness or imbalance, 6-weeks of GPS training did not result in significantly greater improvements in dizziness handicap or balance compared to 6-weeks of SAE training.

Hippoboscids or louse flies (Diptera: Hippoboscidae) are obligate hematophages highly specialized for an ectoparasitic life in the feathers or fur of avian or mammalian hosts, respectively. As part of an existing avian monitoring program in the Dominican Republic, two cases of parasitism by louse flies in a Black-faced Grassquit (Melanospiza bicolor) and a Green Heron (Butorides virescens) were reported. In the laboratory, the flies were examined and identified as the species Ornithoctona erythrocephala. This is the first time this hippoboscid has been observed parasitizing these two bird species, and indeed the first record of it parasitizing a species of the family Thraupidae. Keywords Caribbean, Dominican Republic, ectoparasite, Hippoboscidae, Hispaniola, Ornithoctona erythrocephala Resumen Nuevos registros de especies hospederas de una mosca parásita (Diptera: Hippoboscidae) en bosques montanos de La Española • Los hipobóscidos o moscas piojo (Diptera: Hippoboscidae) son hematófagos obligados altamente especializados para una vida ectoparásita en las plumas de las aves o el pelaje de los mamíferos hospederos. Como parte de un programa de monitoreo de aves que existe en la República Dominicana, se reportaron dos casos de parasitismo por moscas piojos en Melanospiza bicolor y Butorides virescens. En el laboratorio, las moscas fueron examinadas e identificadas como la especie Ornithoctona erythrocephala. Esta es la primera vez que se observa que este hipobóscido parasita a estas dos especies de aves y, de hecho, el primer registro de que parasita una especie de la familia Thraupidae. Palabras clave Caribe, ectoparásito, Hippoboscidae, La Española, Ornithoctona erythrocephala, República Dominicana Résumé Nouvelles mentions d’espèces hôtes d’une mouche parasite (Diptera : Hippoboscidae) dans les forêts de montagne d’Hispaniola • Les hippobosques ou mouches plates (Diptera : Hippoboscidae) sont des espèces hématophages obligatoires hautement spécialisées pour une vie ectoparasitaire dans les plumes des oiseaux ou la fourrure des mammifères. Dans le cadre d’un programme de suivi de l’avifaune en République dominicaine, deux cas de parasitisme par des hippobosques ont été signalés sur un Sporophile cici (Melanospiza bicolor) et un Héron vert (Butorides virescens). En laboratoire, les mouches ont été examinées et identifiées comme appartenant à l’espèce Ornithoctona erythrocephala. C’est la première fois que cet hippobosque est observé comme parasite de ces deux espèces d’oiseaux et comme parasite d’une espèce de la famille des Thraupidae. Mots clés Caraïbes, ectoparasite, Hippoboscidae, Hispaniola, Ornithoctona erythrocephala, République dominicaine

Gaze stability is the ability of the eyes to fixate a stable point when the head is moving in space. Because gaze stability is impaired in peripheral vestibular loss patients, gaze stabilization exercises are often prescribed to facilitate compensation. However, both the assessment and prescription of these exercises are subjective. Accordingly, here we quantified head motion kinematics in patients with vestibular loss while they performed the standard of care gaze stability exercises, both before and after surgical deafferentation. We also correlate the head kinematic data with standard clinical outcome measures. Using inertial measurement units, we quantified head movements in patients as they transitioned through these two vestibular states characterized by different levels of peripheral damage. Comparison with age-matched healthy control subjects revealed that the same kinematic measurements were significantly abnormal in patients both pre- and post-surgery. Regardless of direction, patients took a longer time to move their heads during the exercises. Interestingly, these changes in kinematics suggest a strategy that existed preoperatively and remained symmetric after surgery although the patients then had complete unilateral vestibular loss. Further, we found that this kinematic assessment was a good predictor of clinical outcomes, and that pre-surgery clinical measures could predict post-surgery head kinematics. Thus, together, our results provide the first experimental evidence that patients show significant changes in head kinematics during gaze stability exercises, even prior to surgery. This suggests that early changes in head kinematic strategy due to significant but incomplete vestibular loss are already maladaptive as compared to controls.

BACKGROUND AND PURPOSE This was a double-blinded randomized controlled study to investigate the effects of once-daily incremental vestibulo-ocular reflex (VOR) training over 1 week in people with chronic peripheral vestibular hypofunction. METHODS A total of 24 patients with peripheral vestibular hypofunction were randomly assigned to intervention (n = 13) or control (n = 11) groups. Training consisted of either x1 (control) or incremental VOR adaptation exercises, delivered once daily for 15 minutes over 4 days in 1 week. Primary outcome: VOR gain with video-oculography. Secondary outcomes: Compensatory saccades measured using scleral search coils, dynamic visual acuity, static balance, gait, and subjective symptoms. Between-group differences were analyzed with a linear mixed-model with repeated measures. RESULTS There was a difference in the VOR gain increase between groups (P < 0.05). The incremental training group gain increased during active (13.4% ± 16.3%) and passive (12.1% ± 19.9%) head impulse testing (P < 0.02), whereas it did not for the control group (P = 0.59). The control group had reduced compensatory saccade latency (P < 0.02). Both groups had similarly improved dynamic visual acuity scores (P < 0.05). Both groups had improved dynamic gait index scores (P < 0.002); however, only the incremental group had improved scores for the 2 walks involving head oscillations at approximately 2 Hz (horizontal: P < 0.05; vertical: P < 0.02), increased gait speed (P < 0.02), and step length (P < 0.01) during normal gait, and improved total Dizziness Handicap Inventory (P < 0.05). CONCLUSIONS Our results suggest incremental VOR adaptation significantly improves gain, gait with head rotation, balance during gait, and symptoms in patients with chronic peripheral vestibular hypofunction more so than conventional x1 gaze-stabilizing exercises.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A336).

BACKGROUND: Embedded within most rapid head rotations are gaze shifts, which is an initial eye rotation to a target of interest, followed by a head rotation towards the same target. Gaze shifts are used to acquire an image that initially is outside of the participant’s current field of vision. Currently, there are no tools available that evaluate the functional relevance of a gaze shift. OBJECTIVE: The purpose of our study was to measure dynamic visual acuity (DVA) while performing a gaze shift. METHODS: Seventy-one healthy participants (42.79±16.89 years) and 34 participants with unilateral vestibular hypofunction (UVH) (54.59±20.14 years) were tested while wearing an inertial measurement unit (IMU) sensor on the head and walking on a treadmill surrounded by three monitors. We measured visual acuity during three subcomponent tests: standing (static visual acuity), while performing an active head rotation gaze shift, and an active head rotation gaze shift while walking (gsDVAw). RESULTS: While doing gsDVAw, patients with Left UVH (n = 21) had scores worse (p = 0.023) for leftward (0.0446±0.0943 LogMAR) head rotation compared with the healthy controls (–0.0075±0.0410 LogMAR). Similarly, patients with right UVH (N = 13) had worse (p = 0.025) gsDVAw for rightward head motion (0.0307±0.0481 LogMAR) compared with healthy controls (–0.0047±0.0433 LogMAR). As a whole, gsDVAw scores were worse in UVH compared to the healthy controls when we included the ipsilesional head rotation on both sides gsDVAw (0.0061±0.0421 LogMAR healthy vs. 0.03926±0.0822 LogMAR UVH, p = 0.003). Controlling for age had no effect, the gsDVAw scores of the patients were always worse (p

Background Bilateral vestibular hypofunction is associated with chronic disequilibrium, postural instability, and unsteady gait owing to failure of vestibular reflexes that stabilize the eyes, head, and body. A vestibular implant may be effective in alleviating symptoms. Methods Persons who had had ototoxic (7 participants) or idiopathic (1 participant) bilateral vestibular hypofunction for 2 to 23 years underwent unilateral implantation of a prosthesis that electrically stimulates the three semicircular canal branches of the vestibular nerve. Clinical outcomes included the score on the Bruininks-Oseretsky Test of Motor Proficiency balance subtest (range, 0 to 36, with higher scores indicating better balance), time to failure on the modified Romberg test (range, 0 to 30 seconds), score on the Dynamic Gait Index (range, 0 to 24, with higher scores indicating better gait performance), time needed to complete the Timed Up and Go test, gait speed, pure-tone auditory detection thresholds, speech discrimination scores, and quality of life. We compared participants' results at baseline (before implantation) with those at 6 months (8 participants) and at 1 year (6 participants) with the device set in its usual treatment mode (varying stimulus pulse rate and amplitude to represent rotational head motion) and in a placebo mode (holding pulse rate and amplitude constant). Results The median scores at baseline and at 6 months on the Bruininks-Oseretsky test were 17.5 and 21.0, respectively (median within-participant difference, 5.5 points; 95% confidence interval [CI], 0 to 10.0); the median times on the modified Romberg test were 3.6 seconds and 8.3 seconds (difference, 5.1; 95% CI, 1.5 to 27.6); the median scores on the Dynamic Gait Index were 12.5 and 22.5 (difference, 10.5 points; 95% CI, 1.5 to 12.0); the median times on the Timed Up and Go test were 11.0 seconds and 8.7 seconds (difference, 2.3; 95% CI, -1.7 to 5.0); and the median speeds on the gait-speed test were 1.03 m per second and 1.10 m per second (difference, 0.13; 95% CI, -0.25 to 0.30). Placebo-mode testing confirmed that improvements were due to treatment-mode stimulation. Among the 6 participants who were also assessed at 1 year, the median within-participant changes from baseline to 1 year were generally consistent with results at 6 months. Implantation caused ipsilateral hearing loss, with the air-conducted pure-tone average detection threshold at 6 months increasing by 3 to 16 dB in 5 participants and by 74 to 104 dB in 3 participants. Changes in participant-reported disability and quality of life paralleled changes in posture and gait. Conclusions Six months and 1 year after unilateral implantation of a vestibular prosthesis for bilateral vestibular hypofunction, measures of posture, gait, and quality of life were generally in the direction of improvement from baseline, but hearing was reduced in the ear with the implant in all but 1 participant. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT02725463.).

As the Department of Veterans Affairs (VA) healthcare system seeks to expand access to comprehensive geriatric assessments, evidence-based models of care are needed to support community-dwelling older persons. We evaluated the VA Geriatric Resources for Assessment and Care of Elders (VA-GRACE) program's effect on mortality and readmissions, as well as patient, caregiver, and staff satisfaction.This retrospective cohort included patients admitted to the Richard L. Roudebush VA hospital (2010-2019) who received VA-GRACE services post-discharge and usual care controls who were potentially eligible for VA-GRACE but did not receive services. The VA-GRACE program provided home-based comprehensive, multi-disciplinary geriatrics assessment, and ongoing care. Primary outcomes included 90-day and 1-year all-cause readmissions and mortality, and patient, caregiver, and staff satisfaction. We used propensity score modeling with overlapping weighting to adjust for differences in characteristics between groups.VA-GRACE patients (N = 683) were older than controls (N = 4313) (mean age 78.3 ± 8.2 standard deviation vs. 72.2 ± 6.9 years; p 0.001) and had greater comorbidity (median Charlson Comorbidity Index 3 vs. 0; p 0.001). VA-GRACE patients had higher 90-day readmissions (adjusted odds ratio [aOR] 1.55 [95%CI 1.01-2.38]) and higher 1-year readmissions (aOR 1.74 [95%CI 1.22-2.48]). However, VA-GRACE patients had lower 90-day mortality (aOR 0.31 [95%CI 0.11-0.92]), but no statistically significant difference in 1-year mortality was observed (aOR 0.88 [95%CI 0.55-1.41]). Patients and caregivers reported that VA-GRACE home visits reduced travel burden and the program linked Veterans and caregivers to needed resources. Primary care providers reported that the VA-GRACE team helped to reduce their workload, improved medication management for their patients, and provided a view into patients' daily living situation.The VA-GRACE program provides comprehensive geriatric assessments and care to high-risk, community-dwelling older persons with high rates of satisfaction from patients, caregivers, and providers. Widespread deployment of programs like VA-GRACE will be required to support Veterans aging in place.

A 73-year-old female presented to the emergency department with chief complaint of dizziness after sustaining a fall one month prior to dizziness onset. Although careful examination of eye movement patterns during positional testing was attempted at varying stages of her inpatient admission, her complex nystagmus patterns as a result of traumatic benign paroxysmal vertigo were difficult to manage. In particular, the nystagmus pattern from this case suggests the BPPV was variable and affecting either 1) left posterior semicircular canal (pSCC) exclusively 2) left pSCC and right anterior semicircular canal, 3) left and right pSCC canal. This case illustrates the importance of two critical details; positional testing should include observing nystagmus with fixation removed and an experienced clinician should be involved as early as possible.

The effect of light- and elevated temperature-induced degradation (LeTID) can be nonpermanently reversed by charge carrier injection below the degradation temperature (commonly used degradation temperatures are above ~70 °C). In this study, we show that the rate of temporary recovery depends strongly on the excess carrier density. We observe that the order of the reaction changes from pseudo-zero to first with increasing injection. The rate decreases slightly with increasing temperature. Since the samples can go through multiple degradation/recovery cycles without distinct changes in the degradation kinetics, the experimentally accessible recovered and degraded states are interpreted as manifestations of the equilibrium concentrations of the defect responsible for LeTID at different temperatures. Based on our observations, we argue that the process underlying LeTID degradation is the dissociation of a precursor rather than an association of two or more components. In light of the relation between LeTID susceptibility and bulk hydrogen concentration, we hypothesize that the LeTID precursor dissociates into the LeTID defect and monatomic hydrogen. Numerical simulations of the coupled rate equations including hydrogen interactions well reproduce the experimental observations; according to these results, the presence of a sink for the atomic hydrogen such as dopant atoms is paramount for the LeTID degradation.

Background and purpose Convergence of the eyes during head rotation increases the gain (eye velocity/head velocity) of the vestibulo-ocular reflex (VOR). We sought to know whether convergence would increase the VOR gain (mean + SD) in unilateral vestibular hypofunction (UVH). Methods Vestibulo-ocular reflex gain during ipsi- and contralesional horizontal head rotation at near (15 cm) and far (150 cm) targets was measured in 22 subjects with UVH and 12 healthy controls. Retinal slip was estimated (retinal slip index [RSI]) as the difference between ideal VOR gain (no retinal slip) and the actual VOR gain. Results Convergence did not significantly enhance VOR gain for ipsilesional rotation (mean difference, 0.04; 95% confidence interval [CI], -0.01 to 0.09), near viewing (0.77 ± 0.34) versus far viewing (0.72 ± 0.29), yet the VOR gain during contralesional rotation was greater for near viewing (1.20 ± 0.23) than for far viewing (0.97 ± 0.21; mean difference, 0.23; 95% CI, 0.13-0.32). In the 36% of subjects with recovery of their ipsilesional VOR gain, the vergence effect trended to recover (far VOR gain: 1.06 ± 0.17 vs near VOR gain 1.16 ± 0.21; mean difference, 0.10; 95% CI, -0.02 to 0.22). Ipsilesional head rotation induced greater retinal slip for near (RSI = 0.90 ± 0.34) targets than for far targets (RSI = 0.35 ± 0.29; mean difference, 0.56; 95% CI, 0.51-0.61). Discussion and conclusions The convergence-mediated VOR gain enhancement is preserved during contralesional but impaired during ipsilesional head rotation. Recovery of ipsilesional passive VOR gain does not equate to restored convergence enhancement, although it did increase ∼10%. These data suggest head motion viewing near targets will increase retinal slip, which warrants consideration as a gaze stability exercise for subjects with UVH.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A325).

The silicon surface texture significantly affects the current density and efficiency of perovskite/silicon tandem solar cells. However, only a few studies have explored fabricating perovskite on textured silicon and the effect of texture on perovskite films because of the limitations of solution processes. Here we produce conformal perovskite on textured silicon with a dry two-step conversion process that incorporates lead oxide sputtering and direct contact with methyl ammonium iodide. To separately analyze the influence of each texture structure on perovskite films, patterned texture, high-resolution photoluminescence (μ-PL), and light beam-induced current (μ-LBIC), 3D mapping is used. This work elucidates conformal perovskite on textured surfaces and shows the effects of textured silicon on the perovskite layers with high-resolution 3D mapping. This approach can potentially be applied to any type of layer on any type of substrate. The efficiency of perovskite/silicon tandem solar cells is affected by silicon surface texture, however fabrication processes in solution limit surface studies. Here a perovskite layer on textured silicon is formed through a dry two-step conversion process with lead oxide sputtering and direct contact with methyl ammonium iodide.

Introduction Benign paroxysmal positional vertigo (BPPV) of the horizontal semicircular canal (hSCC) can present with otoconia blocking its lumen (canalith jam), with signs and symptoms that make it difficult to distinguish from central nervous system pathology. Objective Here we report two cases of canalith jam affecting the hSCC and offer a theoretical mechanism based on known vestibular neurophysiology. Methods We use video‐oculography to document the canalith jam and show the moment the otoconia loosen. Results Canalith jam is a rare form of BPPV remedied with repositioning maneuvers. Conclusion Clinicians should consider canalith jam as a mechanism for BPPV when the nystagmus is (a) Direction fixed with fixation removed and during positional testing; (b) Velocity dependent on supine head position; (c) Converts to geotropic directional changing nystagmus.

Colin R Grove,1 Wagner Henrique Souza,2 Patricia L Gerend,3 Cynthia A Ryan,3 Michael C Schubert1,4 1Department of Otolaryngology - Head and Neck Surgery, Laboratory for Vestibular NeuroAdaptation, Johns Hopkins University, Baltimore, MD, 21205, USA; 2KITE, Toronto Rehabilitation Institute – University Health Network, Toronto, ON M5G 2A2, Canada; 3Vestibular Disorders Association (VeDA), Portland, OR, 97211, USA; 4Department of Physical Medicine and Rehabilitation, Johns Hopkins University, Baltimore, MD, 21205, USACorrespondence: Michael C Schubert, Department of Otolaryngology - Head and Neck Surgery, Johns Hopkins University, 601 N. Caroline Street, 6th Floor, Baltimore, MD, 21205, USA, Tel +1 410 955 7381, Email mschube1@jhmi.eduIntroduction: Benign paroxysmal positional vertigo (BPPV) is the most frequently occurring peripheral vestibular disorder. Clinical practice guidelines (CPG) for BPPV exist; however, little is known about how affected patients perceive their condition is being managed. We aimed to leverage registry data to evaluate how adults who report BPPV are managed.Material and Methods: We retrospectively analyzed of data from 1,262 adults (58.4 ± 12.6 years old, 81.1% female, 91.1% White) who were enrolled in the Vestibular Disorders Association Registry from 2014 to 2020. The following patient-reported outcomes were analyzed by proportions for those who did and did not report BPPV: symptoms experienced, falls reported, diagnostics undertaken, interventions received (eg, canalith repositioning maneuvers [CRMs], medications), and responses to interventions.Results: Of the 1,262 adults included, 26% reported being diagnosed with BPPV. Many adults who reported BPPV (83%) also endorsed receiving additional vestibular diagnoses or may have had atypical BPPV. Those with BPPV underwent magnetic resonance imaging and were prescribed medications more frequently than those without BPPV (76% vs 57% [χ2=36.51, p< 0.001] and 85% vs 78% [χ2=5.60, p=0.018], respectively). Falls were experienced by similar proportions of adults with and without BPPV (55% vs 56% [χ2==11.26, p=0.59]). Adults with BPPV received CRMs more often than those without BPPV (86% vs 48%, χ2=127.23, p< 0.001). More registrants with BPPV also endorsed benefit from CRMs compared to those without BPPV (51% vs 12% [χ2=105.30, p< 0.001]).Discussion: In this registry, BPPV was often reported with other vestibular disorders. Healthcare utilization was higher than would be expected with care based on the CPG. The rates of falls in those with and without BPPV are higher than previously reported. Adults with BPPV reported significant differences in how their care is managed and their overall outcomes compared to those without BPPV.Conclusion: Patient-reported outcomes provide useful information regarding the lived experience of adults with BPPV.Keywords: benign paroxysmal positional vertigo, vestibular disorders, falls, canalith repositioning maneuvers

During the COVID-19 pandemic, physical therapists transitioned to provide telehealth in the United States. We sought to determine the experiences of physical therapists delivering telerehabilitation for vestibular disorders including barriers, preferences, and concerns. A survey was created using the results of a focus group and previously published studies. The survey was distributed across social media sites and through email- the link was sent to the orthopedic, neurologic, and geriatric academies of the American Physical Therapy Association list serves. The email was also shared with each of the 50 state chapters of the American Physical Therapy Association. The survey was broken down into five sections: demographic information, physical therapists' general impressions of telehealth, physical therapists' comfort level treating various vestibular diagnoses, and common barriers physical therapists experienced during telehealth sessions. There were 159 completed surveys. More than 80% of physical therapists surveyed agreed that telehealth was an effective platform for vestibular physical therapy. When asked whether physical therapists felt the patient had similar health outcomes with telehealth versus clinic care 68% of physical therapists agreed. For the physical therapists who treated posterior or horizontal canal benign paroxysmal positional vertigo via telehealth, more than 50% were comfortable treating these conditions via telehealth. In analyzing common peripheral vestibular diagnoses treated via telehealth including bilateral vestibular loss, Meniere's disease, and vestibular neuritis more than 75% of the physical therapists reported comfort treating these diagnoses. Similarly, more than 75% of physical therapists who treated central vestibular diagnoses- including mild traumatic brain injury and vestibular migraine- via telehealth reported being comfortable treating these diagnoses. Physical therapists reported several barriers to tele healthcare ranging from concerns about testing balance with no caregiver present (94%) to challenges with providing a written home exercise program (33%). Physical therapists report that telehealth is a viable mechanism for providing rehabilitation for persons with balance and vestibular disorders. For common diagnoses, most physical therapists were comfortable treating vestibular disorders via telehealth. While barriers remain including maintaining patient safety and being able to complete a thorough vestibular exam, telehealth for vestibular physical therapy services holds promise for the delivery of virtual care.

Gallium-doped silicon material has been rapidly gaining importance in the photovoltaic industry as a boron-oxygen defect-free material with promising minority carrier lifetime. We investigate the influence of different cell process flows [passivated emitter and rear cell tunneling-oxide-passivating contact, and a 'hot oxidation' process] on the bulk material quality of an industrial Ga-doped Cz-grown silicon material, as well as its light-and elevated temperature induced degradation degradation behavior under light at elevated temperature. We measure a generally high carrier lifetime level, which remains limited by an unknown recombination-Active defect after most processes. Hydrogenation seems to passivate this unknown defect. In addition, we demonstrate that such high-quality p-Type material can suffer noticeably by iron even for extremely low concentrations below 109 at/cm3.

Characterisation and optimization of next-generation silicon solar cell concepts rely on an accurate knowledge of intrinsic charge carrier recombination in crystalline silicon. Reports of measured lifetimes exceeding the previous accepted parameterisation of intrinsic recombination indicate an overestimation of this recombination in certain injection regimes and hence the need for revision. In this work, twelve high-quality silicon sample sets covering a wide doping range are fabricated using state-of-the-art processing routes in order to permit an accurate assessment of intrinsic recombination based on wafer thickness variation. Special care is taken to mitigate extrinsic recombination due to bulk contamination or at the wafer surfaces. The combination of the high-quality samples with refined sample characterisation and lifetime measurements enables a much higher level of accuracy to be achieved compared to previous studies. We observe that reabsorption of luminescence photons inside the sample must be accounted for to achieve a precise description of radiative recombination. With this effect taken into account, we extract the lifetime limitation due to Auger recombination. We find that the extracted Auger recombination rate can accurately be parameterized using a physically motivated equation based on Coulomb-enhanced Auger recombination for all doping and injection conditions relevant for silicon-based photovoltaics. The improved accuracy of data description obtained with the model suggests that our new parameterisation is more consistent with the actual recombination process than previous models. Due to notable changes in Auger recombination predicted for moderate injection, we further revise the fundamental limiting power conversion efficiency for a single-junction crystalline silicon solar cell to 29.4%, which is within 0.1%abs compared to other recent assessments.

This case study describes transient downbeat nystagmus with vertigo due to a bilateral Bow Hunters Syndrome that was initially treated for 7 months as a peripheral benign paroxysmal positional vertigo. Normal static angiography and imaging studies (magnetic resonance, computed tomography) contributed to the mis-diagnosis. However, not until positional testing with the patient in upright (non-gravity dependent) was a transient downbeat nystagmus revealed with vertigo. The patient was referred for neurosurgical consult. Unfortunately, surgery was delayed due to suicidal ideation and hospitalization. Eventually, vertigo symptoms resolved following a C4-5 anterior cervical dissection and fusion. This case highlights the critical inclusion of non-gravity dependent position testing as an augment to the positional testing component of the clinical examination as well as the extreme duress that prolonged positional vertigo can cause.

Background A clinical pattern of damage to the auditory, visual, and vestibular sensorimotor systems, known as multi-sensory impairment, affects roughly 2% of the US population each year. Within the population of US military service members exposed to mild traumatic brain injury (mTBI), 15–44% will develop multi-sensory impairment following a mild traumatic brain injury. In the US civilian population, multi-sensory impairment-related symptoms are also a common sequela of damage to the vestibular system and affect ~ 300–500/100,000 population. Vestibular rehabilitation is recognized as a critical component of the management of multi-sensory impairment. Unfortunately, the current clinical practice guidelines for the delivery of vestibular rehabilitation are not evidence-based and primarily rely on expert opinion. The focus of this trial is gaze stability training, which represents the unique component of vestibular rehabilitation. The aim of the Incremental Velocity Error as a New Treatment in Vestibular Rehabilitation (INVENT VPT) trial is to assess the efficacy of a non-invasive, incremental vestibular adaptation training device for normalizing the response of the vestibulo-ocular reflex. Methods The INVENT VPT Trial is a multi-center randomized controlled crossover trial in which military service members with mTBI and civilian patients with vestibular hypofunction are randomized to begin traditional vestibular rehabilitation or incremental vestibular adaptation and then cross over to the alternate intervention after a prescribed washout period. Vestibulo-ocular reflex function and other functional outcomes are measured to identify the best means to improve the delivery of vestibular rehabilitation. We incorporate ecologically valid outcome measures that address the common symptoms experienced in those with vestibular pathology and multi-sensory impairment. Discussion The INVENT VPT Trial will directly impact the health care delivery of vestibular rehabilitation in patients suffering from multi-sensory impairment in three critical ways: (1) compare optimized traditional methods of vestibular rehabilitation to a novel device that is hypothesized to improve vestibulo-ocular reflex performance, (2) isolate the ideal dosing of vestibular rehabilitation considering patient burden and compliance rates, and (3) examine whether recovery of the vestibulo-ocular reflex can be predicted in participants with vestibular symptoms. Trial registration ClinicalTrials.gov NCT03846830. Registered on 20 February 2019.

Photon-graviton conversion in a magnetic field is a process that is usually studied at tree level, but the one-loop corrections due to scalars and spinors have also been calculated. Differently from the tree-level process, at one-loop one finds the amplitude to depend on the photon polarization, leading to dichroism. However, previous calculations overlooked a tadpole contribution of the type that was considered to be vanishing in QED for decades but erroneously so, as shown by H. Gies and one of the authors in 2016. Here we compute this missing diagram in closed form, and show that it does not contribute to dichroism., 8 pages, 7 figures, talk given by C. Schubert at Sixteenth Marcel Grossmann Meeting, July 5-10, 2021. Submitted to the conference proceedings

Background: A better understanding of how vestibular asymmetry manifests across tests is important due to its potential implications for balance dysfunction, motion sickness susceptibility, and adaptation to new environments. Objective: We report the results of multiple tests for vestibular asymmetry in 32 healthy participants. Methods: Asymmetry was measured using perceptual reports during unilateral centrifugation, oculomotor responses during visual alignment tasks, vestibulo-ocular reflex gain during head impulse tests, and body rotation during stepping tests. Results: A significant correlation was observed between asymmetries of subjective visual vertical and verbal report during unilateral centrifugation. Another significant correlation was observed between the asymmetries of ocular alignment, vestibulo-ocular reflex gain, and body rotation. Conclusions: These data suggest that there are underlying vestibular asymmetries in healthy individuals that are consistent across various vestibular challenges. In addition, these findings have value in guiding test selection during experimental design for assessing vestibular asymmetry in healthy adults.

Globally, there are nearly three million people living with multiple sclerosis (PLW-MS). Many PLW-MS experience vertigo and have signs of vestibular dysfunction, e.g., low vestibulo–ocular reflex (VOR) gains or the presence of compensatory saccades (CSs), on video head impulse testing (vHIT). We examined whether the vestibular function and compensatory oculomotor behaviors in PLW-MS differed based on the level of MS-related disability. The VOR gain, CS frequency and latency, and gaze position error (GPE) were calculated from the individual traces obtained during six-canal vHIT for 37 PLW-MS (mean age 53.4 ± 12.4 years-old, 28 females) with vertigo and/or an imbalance. The subjects were grouped by their Expanded Disability Status Scale (EDSS) scores: PLW-min-MS (EDSS = 1.0–2.5, n = 8), PLW-mild-MS (EDSS = 3.0–4.5, n = 23), and PLW-moderate-MS (EDSS = 5.0–6.0, n = 6). The between-group differences were assessed with Kruskal–Wallis tests. The VOR gains for most of the canals were higher for PLW-min-MS compared to PLW-mild- and mod-MS, respectively. CS occurred less often in PLW-min-MS versus PLW-mild- and mod-MS, respectively. No clear trend in CS latency was found. The GPE was often lower for PLW-min-MS compared to PLW-mild- and mod-MS, respectively. Thus, our data demonstrate that worse VOR and compensatory oculomotor functions are associated with a greater MS-related disability. PLW-MS may benefit from personalized vestibular physical therapy.

BackgroundTranscranial alternating current stimulation (tACS) may induce frequency-specific aftereffects on brain oscillations in the stimulated location, which could serve as evidence for region-specific neuroplasticity. Aftereffects of tACS on the motor system remain unknown.ObjectiveTo find evidence for aftereffects in short EEG segments following tACS to two critical nodes of the motor network, namely, left motor cortex (lMC) and right cerebellum (rCB). We hypothesized that aftereffects of lMC will be stronger in and around lMC compared to both active stimulation of rCB, as well as inactive (“sham”) control conditions.MethodsTo this end, we employed multivariate pattern analysis (MVPA), and trained a classifier to distinguish between EEG signals following each of the three stimulation protocols. This method accounts for the multitude facets of the EEG signal and thus is more sensitive to subtle modulation of the EEG signal.ResultsEEG signals in both theta (θ, 4-8Hz) and alpha (α, 8-13Hz) were better classified to lMC-tACS compared to rCB-tACS/sham, in and around lMC-tACS stimulation locations (electrodes FC3 and CP3). This effect was associated with a decrease in power following tACS. Source reconstruction revealed significant differences in premotor cortex but not in primary motor cortex as the computational model suggested. Correlation between classification accuracies in θ and α in lMC-tACS was stronger compared to rCB-tACS/sham, suggesting cross-frequency effects of tACS. Nonetheless, θ/α phase-coupling did not differ between stimulation protocols.ConclusionsSuccessful classification of EEG signals to left motor cortex using MVPA revealed focal tACS aftereffects on the motor cortex, indicative of region-specific neuroplasticity.

Health information exchange (HIE) notifications when patients experience cross-system acute care encounters offer an opportunity to provide timely transitions interventions to improve care across systems.To compare HIE notification followed by a post-hospital care transitions intervention (CTI) with HIE notification alone.Cluster-randomized controlled trial with group assignment by primary care team.Veterans 65 or older who received primary care at 2 VA facilities who consented to HIE and had a non-VA hospital admission or emergency department visit between 2016 and 2019.For all subjects, real-time HIE notification of the non-VA acute care encounter was sent to the VA primary care provider. Subjects assigned to HIE plus CTI received home visits and telephone calls from a VA social worker for 30 days after arrival home, focused on patient activation, medication and condition knowledge, patient-centered record-keeping, and follow-up.Primary outcome: 90-day hospital admission or readmission.emergency department visits, timely VA primary care team telephone and in-person follow-up, patients' understanding of their condition(s) and medication(s) using the Care Transitions Measure, and high-risk medication discrepancies.A total of 347 non-VA acute care encounters were included and assigned: 159 to HIE plus CTI and 188 to HIE alone. Veterans were 76.9 years old on average, 98.5% male, 67.8% White, 17.1% Black, and 15.1% other (including Hispanic). There was no difference in 90-day hospital admission or readmission between the HIE-plus-CTI and HIE-alone groups (25.8% vs. 20.2%, respectively; risk diff 5.6%; 95% CI - 3.3 to 14.5%, p = .25). There was also no difference in secondary outcomes.A care transitions intervention did not improve outcomes for veterans after a non-VA acute care encounter, as compared with HIE notification alone. Additional research is warranted to identify transitions services across systems that are implementable and could improve outcomes.