Assessing age-related changes in brain activity during isometric upper and lower limb force control tasks.

Despite the widespread use of older adults (OA) as controls in movement disorder studies, the specific effects of aging on the neural control of upper and lower limb movements remain unclear. While functional MRI paradigms focusing on hand movements are widely used to investigate age-related brain changes, research on lower limb movements is limited due to technical challenges in an MRI environment. This study addressed this gap by examining both upper and lower limb movements in healthy young adults (YA) vs.

Revealing speckle obscured living human retinal cells with artificial intelligence assisted adaptive optics optical coherence tomography.

Background: In vivo imaging of the human retina using adaptive optics optical coherence tomography (AO-OCT) has transformed medical imaging by enabling visualization of 3D retinal structures at cellular-scale resolution, including the retinal pigment epithelial (RPE) cells, which are essential for maintaining visual function. However, because noise inherent to the imaging process (e.g.

Melittin-Phospholipase A Synergism Is Mediated by Liquid-Liquid Miscibility Phase Transition in Giant Unilamellar Vesicles.

The primary constituents of honeybee venom, melittin and phospholipase A (PLA), display toxin synergism in which the PLA activity is significantly enhanced by the presence of melittin. It has been shown previously that this is accomplished by the disruption in lipid packing, which allows PLA to become processive on the membrane surface. In this work, we show that melittin is capable of driving miscibility phase transition in giant unilamellar vesicles (GUVs) and that it raises the miscibility transition temperature () in a concentration-dependent manner.

How experts and novices judge other people's knowledgeability from language use.

How accurate are people in judging someone else's knowledge based on their language use, and do more knowledgeable people use different cues to make these judgments? We address this by recruiting a group of participants ("informants") to answer general knowledge questions and describe various images belonging to different categories (e.g., cartoons, basketball).

Free water imaging unravels unique patterns of longitudinal structural brain changes in Parkinson's disease subtypes.

Background: Research shows that individuals with Parkinson's disease (PD) who have a postural instability and gait difficulties (PIGD) subtype have a faster disease progression compared to those with a tremor dominant (TD) subtype. Nevertheless, our understanding of the structural brain changes contributing to these clinical differences remains limited, primarily because many brain imaging techniques are only capable of detecting changes in the later stages of the disease.

Objective: Free water (FW) has emerged as a robust progression marker in several studies, showing increased values in the posterior substantia nigra that predict symptom worsening.

Erratum: Measuring disparate outcomes of content recommendation algorithms with distributional inequality metrics.

[This corrects the article DOI: 10.1016/j.patter.

Radiologically Isolated Syndrome and the Multiple Sclerosis Prodrome in Pediatrics: Early Features of the Spectrum of Demyelination.

Radiologically isolated syndrome refers to the clinical scenario in which individuals have imaging concerning for multiple sclerosis and would otherwise satisfy radiographic dissemination in space criteria, but do not have any attributable signs or symptoms. Radiologically isolated syndrome has been increasingly recognized in the pediatric population and it is understood certain individuals will transition to a formal diagnosis of multiple sclerosis over time. This review aims to outline the available data within this unique population including the diagnostic criteria, epidemiology, risk factors associated with transitioning to multiple sclerosis, and the current therapeutic landscape.

Seasonality of the Meridional Overturning Circulation in the subpolar North Atlantic.

Understanding the variability of the Atlantic Meridional Overturning Circulation is essential for better predictions of our changing climate. Here we present an updated time series (August 2014 to June 2020) from the Overturning in the Subpolar North Atlantic Program. The 6-year time series allows us to observe the seasonality of the subpolar overturning and meridional heat and freshwater transports.

Imaging the lower limb network in Parkinson's disease.

Background: Despite the significant impact of lower limb symptoms on everyday life activities in Parkinson's disease (PD), knowledge of the neural correlates of lower limb deficits is limited.

Objective: We ran an fMRI study to investigate the neural correlates of lower limb movements in individuals with and without PD.

Methods: Participants included 24 PD and 21 older adults who were scanned while performing a precisely controlled isometric force generation task by dorsiflexing their ankle.

Rate control deficits during pinch grip and ankle dorsiflexion in early-stage Parkinson's disease.

Background: Much of our understanding of the deficits in force control in Parkinson's disease (PD) relies on findings in the upper extremity. Currently, there is a paucity of data pertaining to the effect of PD on lower limb force control.

Objective: The purpose of this study was to concurrently evaluate upper- and lower-limb force control in early-stage PD and a group of age- and gender-matched healthy controls.

Visualization of erythrocyte stasis in the living human eye in health and disease.

Blood cells trapped in stasis have been reported within the microcirculation, but their relevance to health and disease has not been established. In this study, we introduce an imaging approach that reveals the presence of a previously-unknown pool of erythrocytes in stasis, located within capillary segments of the CNS, and present in 100% of subjects imaged. These results provide a key insight that blood cells pause as they travel through the choroidal microvasculature, a vascular structure that boasts the highest blood flow of any tissue in the body.

Widespread subclinical cellular changes revealed across a neural-epithelial-vascular complex in choroideremia using adaptive optics.

Choroideremia is an X-linked, blinding retinal degeneration with progressive loss of photoreceptors, retinal pigment epithelial (RPE) cells, and choriocapillaris. To study the extent to which these layers are disrupted in affected males and female carriers, we performed multimodal adaptive optics imaging to better visualize the in vivo pathogenesis of choroideremia in the living human eye. We demonstrate the presence of subclinical, widespread enlarged RPE cells present in all subjects imaged.

Measuring disparate outcomes of content recommendation algorithms with distributional inequality metrics.

The harmful impacts of algorithmic decision systems have recently come into focus, with many examples of machine learning (ML) models amplifying societal biases. In this paper, we propose adapting income inequality metrics from economics to complement existing model-level fairness metrics, which focus on intergroup differences of model performance. In particular, we evaluate their ability to measure disparities between exposures that individuals receive in a production recommendation system, the Twitter algorithmic timeline.

Photoreceptor and Retinal Pigment Epithelium Relationships in Eyes With Vitelliform Macular Dystrophy Revealed by Multimodal Adaptive Optics Imaging.

Purpose: To assess the structure of cone photoreceptors and retinal pigment epithelial (RPE) cells in vitelliform macular dystrophy (VMD) arising from various genetic etiologies.

Methods: Multimodal adaptive optics (AO) imaging was performed in 11 patients with VMD using a custom-assembled instrument. Non-confocal split detection and AO-enhanced indocyanine green were used to visualize the cone photoreceptor and RPE mosaics, respectively.

Visualizing retinal cells with adaptive optics imaging modalities using a translational imaging framework.

Adaptive optics reflectance-based retinal imaging has proved a valuable tool for the noninvasive visualization of cells in the living human retina. Many subcellular features that remain at or below the resolution limit of current techniques may be more easily visualized with the same modalities in an setting. While most microscopy techniques provide significantly higher resolution, enabling the visualization of fine cellular detail in retinal samples, they do not replicate the reflectance-based imaging modalities of retinal imaging.

Risk factors for hypoxic-ischemic encephalopathy in cases of severe acidosis: A case-control study.

Introduction: The aim of the study was to identify the obstetric risk factors for hypoxic-ischemic encephalopathy (HIE) in infants with asphyxia at birth.

Material And Methods: This multicenter case-control study covered the 5-year period from 2014 through 2018 and included newborns ≥36 weeks of gestation with an umbilical pH at birth ≤7.0.

Clinical Reasoning: A 73-Year-Old Woman With Episodic Dysarthria and Horizontal Binocular Diplopia.

A 73-year-old woman presented with transient episodes of dysarthria and horizontal diplopia. She had stereotactic radiosurgery 18 years prior for a retroclival meningioma. Neurologic examination was notable for right-sided tongue deviation, tongue fasciculations, and intermittent impaired abduction of the right eye.

Perinatal outcome and need of care for term asphyxiated newborns without moderate or severe hypoxic-ischemic encephalopathy.

Aim: Birth asphyxia can lead to organ dysfunction, varying from isolated biological acidosis to hypoxic-ischemic encephalopathy (HIE). Pathophysiology of moderate or severe HIE is now well known and guidelines exist regarding the care required in this situation. However, for newborns without moderate or severe HIE, no consensus is available.

Perceptions of AI engaging in human expression.

Though humans should defer to the superior judgement of AI in an increasing number of domains, certain biases prevent us from doing so. Understanding when and why these biases occur is a central challenge for human-computer interaction. One proposed source of such bias is task subjectivity.

sub-diffraction adaptive optics imaging of photoreceptors in the human eye with annular pupil illumination and sub-Airy detection.

Adaptive optics scanning light ophthalmoscopy (AOSLO) allows non-invasive visualization of the living human eye at the microscopic scale; but even with correction of the ocular wavefront aberrations over a large pupil, the smallest cells in the photoreceptor mosaic cannot always be resolved. Here, we synergistically combine annular pupil illumination with sub-Airy disk confocal detection to demonstrate a 33% improvement in transverse resolution (from 2.36 to 1.

Real-time pixelwise phasor analysis for video-rate two-photon fluorescence lifetime imaging microscopy.

Two-photon fluorescence lifetime imaging microscopy (FLIM) is a widely used technique in biomedical optical imaging. Presently, many two-photon time-domain FLIM setups are limited by long acquisition and postprocessing times that decrease data throughput and inhibit the ability to image fast sub-second processes. Here, we present a versatile two-photon FLIM setup capable of video-rate (up to 25 fps) imaging with graphics processing unit (GPU)-accelerated pixelwise phasor analysis displayed and saved simultaneously with acquisition.

A New England COVID-19 Registry of Patients With CNS Demyelinating Disease: A Pilot Analysis.

Background And Objectives: We sought to define the risk of severe coronavirus disease 2019 (COVID-19) infection requiring hospitalization in patients with CNS demyelinating diseases such as MS and the factors that increase the risk for severe infection to guide decisions regarding patient care during the COVID-19 pandemic.

Methods: A pilot cohort of 91 patients with confirmed or suspected COVID-19 infection from the Northeastern United States was analyzed to characterize patient risk factors and factors associated with an increased severity of COVID-19 infection. Univariate analysis of variance was performed using the Mann-Whitney test or analysis of variance for continuous variables and the χ or Fisher exact test for nominal variables.