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The abstract provides an overview of lymphedema, a chronic and progressive lymphatic disorder that affects millions of people globally. This condition is associated with high costs and comorbidity, with limited treatment options available. Phlebolymphedema, a common form of secondary lymphedema, is linked to the combined effects of lymphatic and chronic venous insufficiencies. Early intervention is crucial to managing the condition; however, early detection remains challenging due to the lack of reliable diagnostic tools. This case study evaluates the clinical utility of a portable tissue analytical tool in a subject with bilateral lower extremity lymphedema undergoing a 60-day self-management program. The study includes details of the subject's profile, the intervention, and the measurements taken with the novel tool.

Decision making has been intensively studied in the posterior parietal cortex in non-human primates on a single neuron level. In humans decision making has mainly been studied with psychophysical tools or with fMRI. Here, we investigated how single neurons from human posterior parietal cortex represent numeric values informing future decisions during a complex two-player game. The tetraplegic study participant was implanted with a Utah electrode array in the anterior intraparietal area (AIP). We played a simplified variant of Black Jack with the participant while neuronal data was recorded. During the game two players are presented with numbers which are added up. Each time a number is presented the player has to decide to proceed or to stop. Once the first player stops or the score reaches a limit the turn passes on to the second player who tries to beat the score of the first player. Whoever is closer to the limit (without overshooting) wins the game. We found that many AIP neurons selectively responded to the face value of the presented number. Other neurons tracked the cumulative score or were selectively active for the upcoming decision of the study participant. Interestingly, some cells also kept track of the opponent’s score. Our findings show that parietal regions engaged in hand action control also represent numbers and their complex transformations. This is also the first demonstration of complex economic decisions being possible to track in single neuron activity in human AIP. Our findings show how tight are the links between parietal neural circuits underlying hand control, numerical cognition and complex decision-making.

There are many electrode types for recording and stimulating neural tissue, most of which necessitate direct contact with the target tissue. These electrodes range from large, scalp electrodes which are used to non-invasively record averaged, low frequency electrical signals from large areas/volumes of the brain, to penetrating microelectrodes which are implanted directly into neural tissue and interface with one or a few neurons. With the exception of scalp electrodes (which provide very low-resolution recordings), each of these electrodes requires a highly invasive, open brain surgical procedure for implantation, which is accompanied by significant risk to the patient. To mitigate this risk, a minimally invasive endovascular approach can be used. Several types of endovascular electrodes have been developed to be delivered into the blood vessels in the brain via a standard catheterization procedure. In this review, the existing body of research on the development and application of endovascular electrodes is presented. The capabilities of each of these endovascular electrodes is compared to commonly used direct-contact electrodes to demonstrate the relative efficacy of the devices. Potential clinical applications of endovascular recording and stimulation and the advantages of endovascular versus direct-contact approaches are presented.

The responsiveness of primary somatosensory cortex (S1) to physical tactile stimuli is well documented but the extent to which it is modulated by vision is unresolved. Additionally, recent literature has suggested that tactile events are represented in S1 in a more complex, generalized manner than its long-established topographic organization. To better characterize S1 function, neural activity was recorded from a tetraplegic patient implanted with microelectrode arrays in S1 during 1s stroking touches to the forearm (evoking numb sensation) or finger (naturalistic sensation). Touch conditions included visually observed first person physical touches, physical touches without vision, and visual touches without physical contact which occurred either to a third person, an inanimate object, or the patient’s own body in virtual reality. Two major findings emerged from this dataset. The first was that vision strongly modulates S1 activity, but only if there is a physical element to the touch, suggesting that passive observation of touches is not sufficient to recruit S1 neurons. The second was that despite the location of the recording arrays in a putative arm area of S1, neural activity was able to represent both arm and finger touches in physical touch conditions. Arm touches were encoded more strongly and specifically, supporting the idea that S1 encodes tactile events primarily through its topographic organization, as well as in a more general manner encompassing larger areas of the body.

Background: Vagus Nerve Stimulation (VNS) paired with rehabilitation improved upper extremity impairment and function in a recent pivotal, randomised, blinded, sham-controlled trial. Here we report post-hoc sub-group analyses from the VNS Rehab trial. We aimed to determine whether treatment effects were consistent across subgroups. Methods: VNS Rehab included 108 participants with moderate to severe arm /hand weakness, at least nine months after ischaemic stroke. They were randomised to receive rehabilitation paired with active VNS or rehabilitation paired with sham stimulation (Control). The primary outcome was the change in iFugl-Meyer Assessment Upper Extremity (FMA-UE) score on the first day after completion of in-clinic therapy. The trial was registered on ClinicalTrials.gov (NCT03131960). We explored the effect of VNS treatment by sex (n=70 males; n=38 females), age (≤ 65 or >65 years)), time from stroke (median time, 2 years) and baseline FMA-UE score (33 moderate). We assessed whether there was any interaction with treatment. No hypotheses were specified prior to this analysis and no formal adjustment was made for multiplicity. Findings: On the first day after completion of in-clinic therapy, the mean (±SD) FMA-UE score increased by 5.0 points (SD 4.4) in the VNS group and by 2.4 points (SD 3.8) in the Control group (p=0.001, between group difference 2.6, 95% CI 1.03 to 4.2). The between group difference was similar across all subgroups (figure). No significant treatment interactions were observed with baseline characteristics. Interpretation: Participants with moderate to severe arm and hand impairment after ischaemic stroke showed clinically meaningful improvements in motor impairment and function with rehabilitation paired with VNS compared to rehabilitation with sham VNS. The response appeared similar across pre-defined subgroups of interest.

Clinicians and scientists alike have long sought to predict the course and severity of chronic post-stroke cognitive and motor outcomes, as the ability to do so would inform treatment and rehabilitation strategies. However, it remains difficult to make accurate predictions about chronic post-stroke outcomes due, in large part, to high inter-individual variability in recovery and a reliance on clinical heuristics rather than empirical methods. The neuroanatomical location of a stroke is a key variable associated with long-term outcomes, and because lesion location can be derived from routinely collected clinical neuroimaging data there is an opportunity to use this information to make empirically based predictions about post-stroke deficits. For example, lesion location can be compared to statistically weighted multivariate lesion-behaviour maps of neuroanatomical regions that, when damaged, are associated with specific deficits based on aggregated outcome data from large cohorts. Here, our goal was to evaluate whether we can leverage lesion-behaviour maps based on data from two large cohorts of individuals with focal brain lesions to make predictions of 12-month cognitive and motor outcomes in an independent sample of stroke patients. Further, we evaluated whether we could augment these predictions by estimating the structural and functional networks disrupted in association with each lesion-behaviour map through the use of structural and functional lesion network mapping, which use normative structural and functional connectivity data from neurologically healthy individuals to elucidate lesion-associated networks. We derived these brain network maps using the anatomical regions with the strongest association with impairment for each cognitive and motor outcome based on lesion-behaviour map results. These peak regional findings became the ‘seeds’ to generate networks, an approach that offers potentially greater precision compared to previously used single-lesion approaches. Next, in an independent sample, we quantified the overlap of each lesion location with the lesion-behaviour maps and structural and functional lesion network mapping and evaluated how much variance each could explain in 12-month behavioural outcomes using a latent growth curve statistical model. We found that each lesion-deficit mapping modality was able to predict a statistically significant amount of variance in cognitive and motor outcomes. Both structural and functional lesion network maps were able to predict variance in 12-month outcomes beyond lesion-behaviour mapping. Functional lesion network mapping performed best for the prediction of language deficits, and structural lesion network mapping performed best for the prediction of motor deficits. Altogether, these results support the notion that lesion location and lesion network mapping can be combined to improve the prediction of post-stroke deficits at 12-months.

Objective. Brain injury is the leading cause of long-term disability worldwide, often resulting in impaired hand function. Brain–machine interfaces (BMIs) offer a potential way to improve hand function. BMIs often target replacing lost function, but may also be employed in neurorehabilitation (nrBMI) by facilitating neural plasticity and functional recovery. Here, we report a novel nrBMI capable of acquiring high-γ (70–115 Hz) information through a unique post-traumatic brain injury (TBI) hemicraniectomy window model, and delivering sensory feedback that is synchronized with, and proportional to, intended grasp force. Approach. We developed the nrBMI to use electroencephalogram recorded over a hemicraniectomy (hEEG) in individuals with TBI. The nrBMI empowered users to exert continuous, proportional control of applied force, and provided continuous force feedback. We report the results of an initial testing group of three human participants with TBI, along with a control group of three skull- and motor-intact volunteers. Main results. All participants controlled the nrBMI successfully, with high initial success rates (2 of 6 participants) or performance that improved over time (4 of 6 participants). We observed high-γ modulation with force intent in hEEG but not skull-intact EEG. Most significantly, we found that high-γ control significantly improved the timing synchronization between neural modulation onset and nrBMI output/haptic feedback (compared to low-frequency nrBMI control). Significance. These proof-of-concept results show that high-γ nrBMIs can be used by individuals with impaired ability to control force (without immediately resorting to invasive signals like electrocorticography). Of note, the nrBMI includes a parameter to change the fraction of control shared between decoded intent and volitional force, to adjust for recovery progress. The improved synchrony between neural modulations and force control for high-γ signals is potentially important for maximizing the ability of nrBMIs to induce plasticity in neural circuits. Inducing plasticity is critical to functional recovery after brain injury.

BACKGROUND: Accurate prediction of clinical impairment in upper extremity motor function following therapy in chronic stroke patients is a difficult task for clinicians, but is key in prescribing appropriate therapeutic strategies. Machine learning is a highly promising avenue with which to improve prediction accuracy in clinical practice. OBJECTIVES: The objective was to evaluate the performance of five machine learning methods in predicting post-intervention upper extremity motor impairment in chronic stroke patients, using demographic, clinical, neurophysiological, and imaging input variables. METHODS: One hundred and two patients (female: 31%, age 61±11 years) were included. The upper extremity Fugl-Meyer Assessment (UE-FMA) was used to assess motor impairment of the upper limb before and after intervention. Elastic-Net (EN), Support Vector Machines (SVM), Artificial Neural Networks (ANN), Classification and Regression Trees (CART), and Random Forest (RF) were used to predict post-intervention UE-FMA. The performances of methods were compared using cross-validated r-squared (R(2)). RESULTS: Elastic-Net performed significantly better than other methods in predicting post-intervention UE-FMA using demographic and baseline clinical data (median [Formula: see text] , [Formula: see text] , [Formula: see text] , [Formula: see text] , [Formula: see text]; p < 0.05). Pre-intervention UE-FMA and the difference in motor threshold (MT) between the affected and unaffected hemispheres were the strongest predictors. The difference in MT had greater importance than the absence or presence of a motor-evoked potential (MEP) in the affected hemisphere. CONCLUSION: Machine learning methods may enable clinicians to accurately predict a chronic stroke patient’s post-intervention UE-FMA. Inter-hemispheric difference in MT is an important predictor of chronic stroke patients’ response to therapy, therefore could be included in prospective studies.

Background The health care systems of low-income countries have severely limited capacity to treat surgical diseases and conditions. There is limited information about which hospital mortality outcomes are suitable metrics in these settings. Methods We did a 1-year observational cohort study of patient admissions to the Surgery and the Obstetrics and Gynecology departments and of newborns delivered at a Ugandan secondary referral hospital. We examined the proportion of deaths captured by standardized metrics of mortality. Results There were 17,015 admissions and 9612 deliveries. A total of 847 deaths were documented: 385 (45.5%) admission deaths and 462 (54.5%) perinatal deaths. Less than one-third of admission deaths occurred during or after an operation (n = 126/385, 32.7%). Trauma and maternal mortality combined with perioperative mortality produced 79.2% (n = 305/385) of admission deaths. Of 462 perinatal deaths, 412 (90.1%) were stillborn, and 50 (10.9%) were early neonatal deaths. The combined metrics of the trauma mortality rate, maternal mortality ratio, thirty-day perioperative mortality rate, and perinatal mortality rate captured 89.8% (n = 761/847) of all deaths documented at the hospital. Conclusions The combination of perinatal, maternal, trauma, and perioperative mortality metrics captured most deaths documented at a Ugandan referral hospital.

Post-starburst galaxies are crucial to disentangling the effect of star formation and quenching on galaxy demographics. They comprise, however, a heterogeneous population of objects, described in numerous ways. To obtain a well-defined and uncontaminated sample, we take advantage of spatially resolved spectroscopy to construct an unambiguous sample of E + A galaxies - post-starburst systems with no observed ongoing star formation. Using data from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) Survey, in the fourth generation of the Sloan Digital Sky Survey (SDSS-IV), we have identified 30 E + A galaxies that lie within the green valley of color-stellar mass space. We first identified E + A candidates by their central, single-fiber spectra and (u-r) color from SDSS DR15, and then further required each galaxy to exhibit E + A properties throughout the entirety of the system to three effective radii. We describe our selection criteria in detail, note common pitfalls in E + A identification, and introduce the basic characteristics of the sample. We will use this E + A sample, which has been assembled with stringent criteria and thus re-establishes a well-defined subpopulation within the broader category of post-starburst galaxies, to study the evolution of galaxies and their stellar populations in the time just after star formation within them is fully quenched., 11 pages, 2 tables, 8 figures and a complete sample appendix

Background Despite public perception, most of the nearly 20 million US veterans have health coverage outside the Veterans Health Administration (VHA), and VHA eligibility and utilization vary across veterans. Out-of-pocket healthcare spending thus remains a potential source of financial hardship for veterans. The Affordable Care Act (ACA) aimed to expand health insurance access, but its effect on veterans’ financial risk protection has not been explored. Objective To evaluate whether ACA implementation was associated with changes in veterans’ risk of catastrophic health expenditures, and to characterize drivers of catastrophic health spending among veterans post-ACA. Design Using multivariable linear probability regression, we examined changes in likelihood of catastrophic health spending after ACA implementation, stratifying by age (18–64 vs 65+), household income tercile, and payer (VHA vs non-VHA). Among veterans with catastrophic spending post-ACA, we evaluated sources of out-of-pocket spending. Participants Nationally representative sample of 13,030 veterans aged 18+ from the 2010 to 2017 Medical Expenditure Panel Survey. Intervention ACA implementation, January 1, 2014. Main Measures Likelihood of catastrophic health expenditures, defined as household out-of-pocket spending exceeding 10% of household income. Key Results Among veterans aged 18–64, ACA implementation was associated with a 26% decrease in likelihood of catastrophic health expenditures (absolute change, −1.4 percentage points [pp]; 95% CI, −2.6 to −0.2; p=0.03), which fell from 5.4% pre-ACA to 3.9% post-ACA. This was driven by a 38% decrease in catastrophic spending among veterans with non-VHA coverage (absolute change, −1.8pp; 95% CI, −3.0 to −0.6; p=0.003). In contrast, catastrophic expenditure rates among veterans aged 65+ remained high, at 13.0% pre- and 12.5% post-ACA. Major drivers of veterans’ spending post-ACA include dental care, prescription drugs, and home care. Conclusions ACA implementation was associated with reduced household catastrophic health expenditures for younger but not older veterans. These findings highlight gaps in veterans’ financial protection and areas amenable to policy intervention. Supplementary Information The online version contains supplementary material available at 10.1007/s11606-021-06807-4.

This cohort study analyzes changes in financial risk protection associated with implementation of the Patient Protection and Affordable Care Act (ACA) across income strata and insurance types.

Myeloid-derived suppressor cells (MDSCs) are a diverse group of cells that are recognized for their remarkable suppressive effects on pro-inflammatory T cells. The pleiotropic nature of these cells, however, has been demonstrated by their differential effects on immune responses in different settings. Our and others’ work has demonstrated suppressive effects of these cells. We previously demonstrated that these cells were mobilized to the lungs during experimental autoimmune encephalomyelitis (EAE), which is a murine model of multiple sclerosis, and potently inhibited CD8+ T cell responses against influenza infection. Interestingly, they appeared to have a lesser effect on CD4+ T cells, and in fact, others have demonstrated that spleen-derived MDSCs could actually promote Th17 differentiation. We sought to determine the role of lung-derived MDSCs on EAE pathogenesis, as excursion through the lungs by pathologic CNS-Ag targeted T cells was shown to be critical for EAE induction. Our results indicate a robust accumulation of granulocytic MDSCs in the lungs of mice during EAE, which could promote Th17 polarization, and which coincided with the trafficking of autoimmune-targeted T cells through the lungs. These studies underscore the pleiotropic effect of MDSCs on T cells and their potential pro-inflammatory phenotypes in neuro-inflammatory disease. Understanding both the intrinsic multifunctional nature of these cells and the ability to influence organ-specific targets such as the CNS from remote organs such as lungs will help to elucidate both mechanisms of disease and possible new therapeutic approaches.

A novel method utilizing ambient thermal desorption ionization with a direct analysis in real-time source integrated with mass spectrometry (DART-MS) was established and applied to the rapid analysis of 3-hydroxy-3-methylglutaric (3-HMG) acid in the neonatal urine. Instrument parameter settings were optimized to obtain high sensitive and accurate determination of 3-HMG acid. The use of helium gas heated to temperature of 400°C was observed to permit deprotonation, 3-HMG acid producing an abundant (M-H)- (m/z 161) in the negative ion mode. The calibration curve was determined to be linear over the range of 0.05-5 mg/L, with the correlation coefficient r = 0.9988 and the relative standard deviations (n = 6) in the range of 1.5-11.8%. The limit of detection was 0.002 mg/L, and the limit of quantitation was 0.007 mg/L. The recoveries ranged from 88.0% to 123.1%. Four urine samples from patients and four simulated urine samples were investigated. The results of DART-MS were in agreement with the values determined using established methods at the hospitals. The proposed method demonstrated significant potential in the application of the high-throughput screening in newborn screening.

The cortical grasp network encodes planning and execution of grasps and processes spoken and written aspects of language. High-level cortical areas within this network are attractive implant sites for brain-machine interfaces (BMIs). While a tetraplegic patient performed grasp motor imagery and vocalized speech, neural activity was recorded from the supramarginal gyrus (SMG), ventral premotor cortex (PMv), and somatosensory cortex (S1). In SMG and PMv, five imagined grasps were well represented by firing rates of neuronal populations during visual cue presentation. During motor imagery, these grasps were significantly decodable from all brain areas. During speech production, SMG encoded both spoken grasp types and the names of five colors. Whereas PMv neurons significantly modulated their activity during grasping, SMG's neural population broadly encoded features of both motor imagery and speech. Together, these results indicate that brain signals from high-level areas of the human cortex could be used for grasping and speech BMI applications.

Background Previously healthy firefighters with World Trade Center (WTC) dust exposure developed airway disease. Risk factors for irritant-associated asthma/COPD overlap are poorly defined. Methods This study included 2,137 WTC-exposed firefighters who underwent a clinically indicated bronchodilator pulmonary function test (BD-PFT) between 9/11/2001 and 9/10/2017. A post-BD FEV1 increase of > 12% and 200 mL from baseline defined asthma, and a post-BD FEV1/FVC ratio Results BD-PFT diagnosed asthma/COPD overlap in 99 subjects (4.6%), isolated-asthma in 202 (9.5%), and isolated-COPD in 215 (10.1%). Eosinophil concentration ≥ 300 cells/μL was associated with increased risk of asthma/COPD overlap (hazard ratio [HR], 1.85; 95% CI, 1.16-2.95) but not with isolated-asthma or isolated-COPD. Serum IL-4 also predicted asthma/COPD overlap (HR, 1.51 per doubling of cytokine concentration; 95% CI, 1.17-1.95). Greater IL-21 concentration was associated with both isolated-asthma and isolated-COPD (HRs of 1.73 [95% CI, 1.27-2.35] and 2.06 [95% CI, 1.31-3.23], respectively). Conclusions In WTC-exposed firefighters, elevated blood eosinophil and IL-4 levels are associated with subsequent asthma/COPD overlap. Disease-specific T-helper cell type 2 biomarkers present years before diagnosis suggest patient-intrinsic predisposition to irritant-associated asthma/COPD overlap.

Simple Summary Colorectal cancer (CRC) is the third most common cancer worldwide. Metastasis to secondary organs, such as the liver and lungs, is a key driver of CRC-related mortality. The tumor microenvironment, which consists of the primary cancer cells, as well as associated support and immune cells, significantly affects the behavior of CRC cells at the primary tumor site, as well as in metastatic lesions. In this paper, we review the role of the individual components of the tumor microenvironment on tumor progression, immune evasion, and metastasis, and we discuss the implications of these components on antitumor therapies. Abstract Colorectal cancer (CRC) is the third most common malignancy and the second most common cause of cancer-related mortality worldwide. A total of 20% of CRC patients present with distant metastases, most frequently to the liver and lung. In the primary tumor, as well as at each metastatic site, the cellular components of the tumor microenvironment (TME) contribute to tumor engraftment and metastasis. These include immune cells (macrophages, neutrophils, T lymphocytes, and dendritic cells) and stromal cells (cancer-associated fibroblasts and endothelial cells). In this review, we highlight how the TME influences tumor progression and invasion at the primary site and its function in fostering metastatic niches in the liver and lungs. We also discuss emerging clinical strategies to target the CRC TME.

Key Points Question Was the implementation of the Patient Protection and Affordable Care Act (ACA) associated with improved financial protection for US adults receiving care for traumatic injuries? Findings In this cross-sectional study of 6288 adult patients with traumatic injury, implementation of the ACA was associated with 31% lower odds of catastrophic health expenditures. Financial protection gains were greatest in lowest-income patients targeted by Medicaid expansion, who experienced 30% lower out-of-pocket spending and 39% lower odds of catastrophic expenditures. Meaning Implementation of the ACA was associated with improved financial protection for US adults with traumatic injury, particularly those with the lowest incomes., This cross-sectional study evaluates the association of the implementation of the US Patient Protection and Affordable Care Act with out-of-pocket spending, premiums, and catastrophic health expenditures among adults with traumatic injuries., Importance Trauma is an expensive and unpredictable source of out-of-pocket spending for American families. The Patient Protection and Affordable Care Act (ACA) sought to improve financial protection by expanding health insurance coverage, but its association with health care spending for patients with traumatic injury remains largely unknown. Objective To evaluate the association of ACA implementation with out-of-pocket spending, premiums, and catastrophic health expenditures (CHE) among adult patients with traumatic injury. Design, Setting, and Participants Data from a nationally representative sample of US adults aged 19 to 64 years who had a hospital stay or emergency department visit for a traumatic injury from January 2010 to December 2017 were analyzed using the Medical Expenditure Panel Survey. Multivariable generalized linear models were used to evaluate changes in spending after ACA implementation. Additionally, 4 income subgroups were evaluated based on ACA thresholds for program eligibility: lowest-income patients (earning 138% or less of the federal poverty level [FPL]), low-income patients (earning 139% to 250% of the FPL), middle-income patients (earning 251% to 400% of the FPL), and high-income patients (earning more than 400% of the FPL). Data were analyzed from February to December 2019. Exposures Implementation of the ACA, beginning January 1, 2014. Main Outcomes and Measures Out-of-pocket spending, premium spending, out-of-pocket plus premium spending, and likelihood of experiencing CHE, defined as out-of-pocket plus premium spending exceeding 19.5% of family income. Results Of the 6288 included patients, 2995 (weighted percentage, 51.3%) were male, and the mean (SD) age was 41.4 (12.8) years. Implementation of the ACA was associated with 31% lower odds of CHE (adjusted odds ratio, 0.69; 95% CI, 0.54 to 0.87; P = .002). Changes were greatest in lowest-income patients, who experienced 30% lower out-of-pocket spending (adjusted percentage change, −30.4%; 95% CI, −46.6% to −9.4%; P = .01), 26% lower out-of-pocket plus premium spending (adjusted percentage change, −26.3%; 95% CI, −41.0% to −8.1%; P = .01), and 39% lower odds of CHE (adjusted odds ratio, 0.61; 95% CI, 0.44 to 0.84; P = .002). Low-income patients experienced decreased out-of-pocket spending and out-of-pocket plus premium spending but no changes in CHE, while middle-income and high-income patients experienced no significant changes in any spending outcome. In the post-ACA period, 1 in 11 of all patients with traumatic injury and 1 in 5 with the lowest incomes continued to experience CHE each year. Conclusions and Relevance Implementation of the ACA was associated with improved financial protection for US adults with traumatic injury, especially lowest-income individuals targeted by the law’s Medicaid expansions. Despite these gains, injured patients remain at risk of financial strain.

Using data from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) Survey, we examined a subsample of 29 E+A galaxy candidates in the Coma Cluster. We created spatially-resolved maps of spectral features and the kinematics of the underlying stellar population by utilizing the Marvin toolkit. We rule out star formation in the entire subsample, and do not find evidence for AGN activity. For the majority of the subsample, stellar rotation is coherent.

In the study of large astronomical data sets, virtual reality (VR) can help build valuable spatial intuition for scientific discovery. We created VR visualizations of E+A galaxies and candidates in four nearby clusters of galaxies: Leo, Virgo, Hercules, and Coma. E+A's are a type of post-starburst galaxy in which all star formation has been recently (∼1 Gyr ago) quenched. Our E+A samples were assembled and cataloged by the Y/Dim collaboration through visual and quantitative analysis of SDSS DR16 spectra. The visualizations are designed for Oculus VR headsets, and utilize C# scripts which interface with the Unity engine, including public domain code and code developed by the lead author. We use these visualizations to find features of the aforementioned galaxy clusters: for instance, a “nose” of low velocity objects in the center of the Virgo cluster and a collection of E+A candidates along a galactic filament in the Coma cluster.

D-Tyrosine inhibits formation and triggers disassembly of bacterial biofilm and has been proposed for biofouling control applications. This study probes the impact of D-tyrosine in different biofilm formation stages in both G+ and G- bacteria, and reveals a non-monotonic correlation between D-tyrosine concentration and biofilm inhibition effect. In the attachment stage, cell adhesion was studied in a flow chamber, where D-tyrosine caused significant reduction in cell attachment. Biofilms formed by Pseudomonas aeruginosa and Bacillus subtilis were characterized by confocal laser scanning microscopy as well as quantitative analysis of cellular biomass and extracellular polymeric substances. D-Tyrosine exhibited strong inhibitive effects on both biofilms with an effective concentration as low as 5 nM; the biofilms responded to D-tyrosine concentration change in a non-monotonic, bi-modal pattern. In addition, D-tyrosine showed notable and different impact on EPS production by G+ and G- bacteria. Extracellular protein was decreased in P. aeruginosa biofilms, but increased in those of B. subtilis. Exopolysaccharides production by P. aeruginosa was increased at low concentrations and reduced at high concentrations while no impact was found in B. subtilis. These results suggest that distinct mechanisms are at play at different D-tyrosine concentrations and they may be species specific. Dosage of D-tyrosine must be carefully controlled for biofouling control applications.

E+A galaxies are post-starburst galaxies that have undergone a recent, complete quenching of star formation. We have analyzed a color-constrained sample of galaxies from the Sloan Digital Sky Survey within a 77.′5 radius of the center of the Leo cluster of galaxies (A1367; J2000 11:44:36.5 + 19:45:32) within 3000 km s−1 of Leo’s redshift of z = 0.022 to identify and survey the E+A galaxy candidates in the cluster. Within this sample, we classified 52 of these galaxies as E+A galaxy candidates based on their spectral shapes, u–r color, lack of Hα emission, and higher-order hydrogen Balmer absorption. We further subdivide this group into “blue” and “green” E+A candidates. Our results show that the E+A galaxy candidates are distributed across the northwest and southeast subclusters of Leo, possibly as a result of merging between the two subclusters.

We have spectroscopically identified 600 new E+A galaxies and candidates across 16 fields totaling roughly 480 square degrees in the Sloan Digital Sky Survey. E+A galaxies are post-starburst systems that have undergone a significant burst of star formation within the past 1–2 Gyr and are now fully quenched. They comprise a small population that is key to understanding the transition from star-forming to quiescent galaxies. Our survey focused on four nearby rich clusters of galaxies and their surroundings: Virgo, Coma, Leo, and Hercules. 356 candidates were identified in the clusters, and an additional 244 were identified in control fields or otherwise outside cluster bounds. Understanding the distribution and dynamics of the E+As has the potential to shed light on the evolutionary mechanisms present within nearby cluster environments. In this note, we give a brief overview of our selection processes and locations, and report on ongoing analyses of the sample.

E+A galaxies are post-starburst galaxies that have recently undergone complete quenching of their star formation, making them a valuable source for studying the evolution of galaxies and their environments. Using the Extended Virgo Cluster Catalog, we manually identified 125 “green” and 24 “blue” E+A galaxy candidates within the Virgo Cluster based on their spectral shape, u − r color, lack of Hα emission, and hydrogen Balmer absorption. Interestingly, we found a higher density of E+A galaxy candidates in the Virgo Cluster than that of most other low-redshift clusters, and several regions of particularly high E+A density within the Virgo Cluster. The large number of E+As in and around the Virgo Cluster hints at the influence of a dense galaxy environment on the formation of E+A galaxies, and the potential value of E+A galaxies as a diagnostic tool to study the evolution of clusters.