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We present an analysis of Epoch of Reionization data from Phase II of the Murchison Widefield Array using the \texttt{simpleDS} delay spectrum pipeline. Prior work analyzed the same observations using the FHD/$\varepsilon$ppsilon imaging pipeline, and so the present analysis represents the first time that both principal types of 21 cm cosmology power spectrum estimation approaches have been applied to the same data set. Our limits on the 21 cm power spectrum amplitude span a range in $k$ space of $|k| < 1~h_{100}{\rm Mpc}^{-1}$ with a lowest measurement of $\Delta^2(k) \leq$ $4.58\times10^3$ mK$^2$ at $k = 0.190 h_{100}\rm{Mpc}^{-1}$ and $z = 7.14$. In order to achieve these limits, we need to mitigate a previously unidentified common mode systematic in the data set. If not accounted for, this systematic introduces an overall \emph{negative} bias that can make foreground contaminated measurements appear as stringent, noise-limited constraints on the 21 cm signal amplitude. The identification of this systematic highlights the risk in modeling systematics as positive-definite contributions to the power spectrum and in ``conservatively'' interpreting all measurements as upper limits., Comment: 19 pages, 12 figures, Accepted by MNRAS; Updated to match published version

Measurements of the one-point probability distribution function and higher-order moments (variance, skewness, and kurtosis) of the high-redshift 21 cm fluctuations are among the most direct statistical probes of the non-Gaussian nature of structure formation and evolution during reionization. However, contamination from astrophysical foregrounds and instrument systematics pose significant challenges in measuring these statistics in real observations. In this work, we use forward modelling to investigate the feasibility of measuring 21 cm one-point statistics through a foreground avoidance strategy. Leveraging the characteristic wedge-shape of the foregrounds in k-space, we apply a wedge-cut filter that removes the foreground contaminated modes from a mock data set based on the Hydrogen Epoch of Reionization Array (HERA) instrument, and measure the one-point statistics from the image-space representation of the remaining non-contaminated modes. We experiment with varying degrees of wedge-cutting over different frequency bandwidths and find that the centre of the band is the least susceptible to bias from wedge-cutting. Based on this finding, we introduce a rolling filter method that allows reconstruction of an optimal wedge-cut 21~cm intensity map over the full bandwidth using outputs from wedge-cutting over multiple sub-bands. We perform Monte Carlo simulations to show that HERA should be able to measure the rise in skewness and kurtosis near the end of reionization with the rolling wedge-cut method if foreground leakage from the Fourier transform window function can be controlled., 13 pages, 10 figures, Accepted to MNRAS

Supplementary Table 1. Primers used for qPCR reactions and piRNA mimics used for in vitro functional analyses.Supplementary Table 2. Characteristics of GliomaScan subjects included in piRNA SNP imputation and association analysis. Supplementary Table 3. Differentially expressed transcripts 24-hours post piR-598-WT or NC transfection in U87 (FDR-adjusted P < 0.05) by fold-change. Supplementary Figure 1. Flowchart of piRNA SNP selection, imputation, and analysis for association study. Supplementary Figure 2. Quantile-quantile (QQ) plot of observed vs. expected chi-square distribution from association analysis of input genotyping data. Supplementary Figure 3. piR-18913, piR-598, piR-11714, and piR-3266 expression in U87, A172, and NHA cell lines by qPCR. Supplementary Figure 4. Expression array validation results. Five genes were selected for validation of expression array results by qPCR.

Background: PIWI-interacting RNAs (piRNAs), the largest class of noncoding RNAs in mammals, cooperate with PIWI proteins to safeguard the genome from insertional mutations during germline development. Although a growing number of studies have linked the PIWI–piRNA pathway to carcinogenesis, the role of piRNAs in glioma has not been explored.Methods: Utilizing directly measured and imputed genotypes from the GliomaScan genome-wide association study (1,840 cases and 2,401 controls), genetic variants in 1,428 piRNAs were analyzed for association with glioma risk. In vitro assays were performed to interrogate the functional impact of a top identified piRNA and its variant allele.Results: Variants in five piRNAs were considered to be associations of interest and four of these showed narrow clusters of enhanced association signals surrounding the index variant. Functional analyses of one of these piRNAs, piR-598, revealed that transfection of the wild-type piRNA impacted expression of genes involved in cell death/survival and reduced glioma cell viability and colony formation. However, upon delivery of piR-598 containing the variant allele at rs147061479 [OR, 1.80; 95% confidence interval (CI), 1.33–2.46; P = 1.69 × 10−4], cell proliferation was sharply increased.Conclusions: The genetic association analysis identifies several piRNAs associated with glioma risk, and follow-up functional analyses suggest that variant rs147061479 in piR-598 increases glioma risk by abolishing the tumor-suppressive function of piR-598, instead conferring growth-promoting properties.Impact: This transdisciplinary study demonstrates a role of piRNAs in gliomagenesis by evidence from both post-GWAS and in vitro functional analyses and supports expanded investigation into the link between the PIWI–piRNA pathway and cancer. Cancer Epidemiol Biomarkers Prev; 25(7); 1073–80. ©2016 AACR.

Exoskeleton devices can reduce metabolic cost, increase walking speed, and augment load-carrying capacity. However, little is known about the effects of powered assistance on the sensory information required to achieve these tasks. To learn how to use an assistive device, humans must integrate novel sensory information into their internal model, but under certain sensory conditions, this may present a challenge. We investigated the exoskeleton-induced changes in balance performance and the sensory system adaptations during quiet standing. We asked 11 unimpaired adults to perform a virtual reality-based test of sensory integration in balance (VRSIB) on two days while wearing the exoskeleton either unpowered, using proportional myoelectric control, or with regular shoes. We measured postural sway, equilibrium scores, and sensory ratios. In addition, we measured postural control strategy, joint kinematics and kinetics, and muscle activity. Results showed improvement in balance performance when wearing the exoskeleton on firm ground. The opposite occurred when standing on an unstable platform with eyes closed or when the visual information was non-veridical. The balance performance was equivalent when the exoskeleton was powered versus unpowered in all conditions except when both the support surface and the visual information were altered. We argue that in stable ground the passive stiffness of the device dominates the postural task. In contrast, when the ground becomes unstable the passive stiffness negatively affects balance performance. Furthermore, when the visual input to the user is non-veridical, exoskeleton assistance can magnify erroneous muscle inputs and negatively impact the user's postural control.

Cross-correlating 21cm and Ly$\alpha$ intensity maps of the Epoch of Reionization (EoR) promises to be a powerful tool for exploring the properties of the first galaxies. Next-generation intensity mapping experiments such as the Hydrogen Epoch of Reionization Array (HERA) and SPHEREx will individually probe reionization through the power spectra of the 21cm and Ly$\alpha$ lines respectively, but will be limited by bright foregrounds and instrumental systematics. Cross-correlating these measurements could reduce systematics, potentially tightening constraints on the inferred astrophysical parameters. In this study, we present forecasts of cross-correlation taking into account the effects of exact uv-sampling and foreground filtering to estimate the feasibility of HERAxSPHEREx making a detection of the 21cm-Ly$\alpha$ cross-power spectrum. We also project the sensitivity of a cross-power spectrum between HERA and the proposed next-generation Cosmic Dawn Intensity Mapper. By isolating the sources of uncertainty, we explore the impacts of experimental limitations such as foreground filtering and Ly$\alpha$ thermal noise uncertainty have on making a detection of the cross-power spectrum. We then implement this strategy in a simulation of the cross-power spectrum and observational error to identify redshifts where fiducial 21cmFAST models predict the highest signal-to-noise detection ($z \sim 8$). We conclude that detection of the SPHEREx-HERA cross-correlation will require an optimistic level of 21cm foreground filtering, as well as deeper thermal noise integrations due to a lack of overlapping sensitive modes but for CDIM with its larger range of scales and lower noise forecast detection levels, may be possible even with stricter 21cm foreground filtering., Comment: 11 pages, 6 figures, Accepted by MNRAS

Observation of redshifted 21-cm signal from the Epoch of Reionization (EoR) is challenging due to contamination from the bright foreground sources that exceed the signal by several orders of magnitude. The removal of this very high foreground relies on accurate calibration to keep the intrinsic property of the foreground with frequency. Commonly employed calibration techniques for these experiments are the sky model-based and the redundant baseline-based calibration approaches. However, the sky model-based and redundant baseline-based calibration methods could suffer from sky-modeling error and array redundancy imperfection issues, respectively. In this work, we introduce the hybrid correlation calibration ("CorrCal") scheme, which aims to bridge the gap between redundant and sky-based calibration by relaxing redundancy of the array and including sky information into the calibration formalisms. We demonstrate the slight improvement of power spectra, about $-6\%$ deviation at the bin right on the horizon limit of the foreground wedge-like structure, relative to the power spectra before the implementation of "CorrCal" to the data from the Precision Array for Probing the Epoch of Reionization (PAPER) experiment, which was otherwise calibrated using redundant baseline calibration. This small improvement of the foreground power spectra around the wedge limit could be suggestive of reduced spectral structure in the data after "CorrCal" calibration, which lays the foundation for future improvement of the calibration algorithm and implementation method., Comment: 18 pages, 12 figures, MNRAS in press

The locations of Ly-$\alpha$ emitting galaxies (LAEs) at the end of the Epoch of Reionisation (EoR) are expected to correlate with regions of ionised hydrogen, traced by the redshifted 21~cm hyperfine line. Mapping the neutral hydrogen around regions with detected and localised LAEs offers an avenue to constrain the brightness temperature of the Universe within the EoR by providing an expectation for the spatial distribution of the gas, thereby providing prior information unavailable to power spectrum measurements. We use a test set of 12 hours of observations from the Murchison Widefield Array (MWA) in extended array configuration, to constrain the neutral hydrogen signature of 58 LAEs, detected with the Subaru Hypersuprime Cam in the \textit{Silverrush} survey, centred on $z$=6.58. We assume that detectable emitters reside in the centre of ionised HII bubbles during the end of reionization, and predict the redshifted neutral hydrogen signal corresponding to the remaining neutral regions using a set of different ionised bubble radii. A prewhitening matched filter detector is introduced to assess detectability. We demonstrate the ability to detect, or place limits upon, the amplitude of brightness temperature fluctuations, and the characteristic HII bubble size. With our limited data, we constrain the brightness temperature of neutral hydrogen to $\Delta{\rm T}_B, Comment: 9 pages, 6 figures, accepted for publication in MNRAS

Background Merkel cell carcinoma (MCC) is an aggressive neuroendocrine carcinoma of the skin. Our report describes the evolution of management and characteristics associated with recurrence, disease-specific survival (DSS) and overall survival (OS) in the treatment of MCC. Methods A single institution retrospective review of MCC and SEER data to determine factors associated with RFS, DSS, and OS using a multivariable Cox regression on inverse-probability weighted cohorts. Results One hundred fifty-nine patients were identified with a median age of 75. Of these, 96% were Caucasian and 60% male. Fifty-eight out of 159 (36%) of all patients were deceased with 21/58 (36%) dead from MCC with a median follow-up of 3.1 years. Institutionally, trends over time demonstrated an increased use of immunotherapy with a concomitant decrease in chemotherapy and decreased use of radiotherapy alone. Institutionally and nationally, there has been increased surgical nodal staging. Institutionally, factors associated with shorter DSS included advanced age, active cigarette smoker (p = 0.002), cT2 disease (p = 0.007), and MCC with unknown primary (p p p p = 0.002), and cT2 disease (HR 9.59, p Conclusion Changing practice patterns in MCC management have been driven by the adoption of immunotherapy. Our study highlights that competing risks of mortality in MCC patients likely prevents OS from being an accurate surrogate outcome measure to understand factors associated with DSS.

We present a Bayesian jackknife test for assessing the probability that a data set contains biased subsets, and, if so, which of the subsets are likely to be biased. The test can be used to assess the presence and likely source of statistical tension between different measurements of the same quantities in an automated manner. Under certain broadly applicable assumptions, the test is analytically tractable. We also provide an open-source code, chiborg, that performs both analytic and numerical computations of the test on general Gaussian-distributed data. After exploring the information theoretical aspects of the test and its performance with an array of simulations, we apply it to data from the Hydrogen Epoch of Reionization Array (HERA) to assess whether different sub-seasons of observing can justifiably be combined to produce a deeper 21 cm power spectrum upper limit. We find that, with a handful of exceptions, the HERA data in question are statistically consistent and this decision is justified. We conclude by pointing out the wide applicability of this test, including to CMB experiments and the H0 tension.

There is evidence of the therapeutic potential of intranasal oxytocin for the treatment of pain and various psychiatric disorders, however, there is scant evidence that oxytocin reaches the brain. We quantified the concentration and distribution pattern of [125I]-radiolabeled oxytocin in the brains and peripheral tissues of rats after intranasal delivery using gamma counting and autoradiography, respectively. Radiolabel was detected in high concentrations in the trigeminal and olfactory nerves as well as in brain regions along their trajectories. Considerable concentrations were observed in the blood, however, relatively low levels of radiolabel were measured in peripheral tissues. The addition of a mucoadhesive did not enhance brain concentrations. These results provide support for intranasal OT reaching the brain via the olfactory and trigeminal neural pathways. These findings will inform the design and interpretation of clinical studies with intranasal oxytocin.

Objectives To investigate factors and complications associated with prolonged inpatient length of stay (LOS) in patients who receive total laryngectomy (TL), and to analyze its effect on short‐term and long‐term overall survival (OS). Methods The National Cancer Database (NCDB) was queried from 2004 to 2016 for patients with laryngeal cancer, who received TL within 60 days of diagnosis, and who had an inpatient LOS ≥1 night. Multivariable binary logistic regression and survival analyses on propensity score matched cohorts with Kaplan‐Meier analysis and extended Cox regression were utilized. Results Eight thousand two hundred and ninety‐eight patients from the NCDB were included. Median inpatient LOS was 8 days after TL (IQR: 7, 12). Prolonged LOS was defined as above the 75th percentile or 13 days or greater. On multivariable analysis, increasing patient age (OR 1.14 per 10 years, P = .003), female sex (OR 1.35, P

The introduction of gas warfare in World War One was impactful, as it both expanded the breadth of warfare and fueled the invention of techniques required to treat these new injuries. Gas injuries were responsible for 91,000 of 1.3 million deaths in World War One. Gassed soldiers had wounds which the world had never seen. They presented in large scale to medical tents and base hospitals across Europe. As gas casualties poured in, doctors and nurses had to treat these conditions in the best way they knew. Gas warfare changed how war was performed and how casualties of this attack were treated. The techniques learned from treating the multitudes of men with gas burns led to advances in the field of burn care, which have helped to improve mortality and reduce morbidity in hospitals across the world.

In 2014, the Radiation Therapy Oncology Group 1221 trial was initiated to analyze whether surgery with risk-based radiation therapy or chemoradiation therapy was superior to chemoradiation therapy alone in patients with clinically staged T1-2N1-2bM0 HPV-negative oropharyngeal squamous cell carcinoma. However, the study was prematurely terminated. Given the lack of a randomized controlled trial, we retrospectively approached the same question using large national cancer databases.Retrospective cohort study.The National Cancer Database and Surveillance, Epidemiology, and End Results (SEER) program from 2010 to 2016.We identified 3004 patients in the National Cancer Database and 670 patients in the SEER database. Statistical techniques included Kaplan-Meier survival analysis, binary and multinomial logistic regressions, Cox proportional hazard regressions, and inverse propensity score weighting.On weighted multivariable Cox regression, patients recommended to receive frontline surgery had improved overall survival as compared with those recommended to receive chemoradiation therapy alone (hazard ratio [HR], 0.77; 95% CI, 0.68-0.86). On post hoc multivariable analysis based on therapy actually received, frontline surgery with adjuvant chemoradiation therapy was associated with improved overall survival (HR, 0.59; 95% CI, 0.50-0.71) as compared with chemoradiation therapy without surgery. Analysis of the SEER cohort revealed improved overall survival (HR, 0.69; 95% CI, 0.54-0.87) and head and neck cancer-specific survival (HR, 0.59; 95% CI, 0.41-0.84) in patients recommended to receive frontline surgery over chemoradiation therapy alone.Our findings support the use of surgery with risk-based addition of adjuvant therapy in patients with cT1-2N1-2bM0 HPV-negative oropharyngeal cancer.

We aimed to evaluate trends and outcomes of surgical approaches to thyroid surgery. We hypothesized that there have been changes over time in the utilization of approaches to thyroidectomy, including endoscopic, robotic, and open approaches, and that patient outcomes may differ between open surgery and endoscopic or robotic approaches.Retrospective analysis.The National Cancer Database (NCDB) was queried between 2010 and 2016.National cohort of patients. Descriptive statistics were performed using χWe identified 217,938 patients within the NCDB. While endoscopic thyroid surgery increased, relatively, in use over time (0.93% to 2.34% of cases in 2010 and 2016, respectively), robotic thyroid surgery started to decline relatively to other approaches from 2013 to 2016 (0.39% to 0.25% of cases, respectively). The endoscopic approach was performed more commonly than the robotic approach within individual facilities that have reported both procedures (Endoscopic thyroid surgery has increased in utilization since 2004 but may have worse morbidity and mortality outcomes compared to open surgery.

We acknowledge the support of the Australian Renewable Energy Agency (ARENA), the Australian Centre for Advanced Photovoltaics (ACAP), and the ANFF ACT Node in carrying out this research. H.T.N. acknowledges the fellowship support of the Australian Centre for Advanced Photovoltaics. T.P.W. is the recipient of an Australian Research Council Future Fellowship (Project No. FT180100302) funded by the Australian Government.

We present a broadband map of polarized diffuse emission at 167-198 MHz developed from data from the Murchison Widefield Array (MWA). The map is designed to improve visibility simulation and precision calibration for 21 cm Epoch of Reionization (EoR) experiments. It covers a large swath - 11,000 sq. deg. - of the Southern Hemisphere sky in all four Stokes parameters and captures emission on angular scales of 1 to 9 degrees. The band-averaged diffuse structure is predominantly unpolarized but has significant linearly polarized structure near RA = 0 h. We evaluate the accuracy of the map by combining it with the GLEAM catalog and simulating an observation from the MWA, demonstrating that the accuracy of the short baselines (6.1-50 wavelengths) now approaches the accuracy of the longer baselines typically used for EoR calibration. We discuss how to use the map for visibility simulation for a variety of interferometric arrays. The map has potential to improve calibration accuracy for experiments such as the Hydrogen Epoch of Reionization Array (HERA) and the forthcoming Square Kilometre Array (SKA) as well as the MWA., Comment: Accepted for publication in MNRAS

The migration of mobile ions has long been considered a source of performance degradation in devices based on halide perovskites, but details regarding the mechanisms and extent of this problem remain scarce. Here we report the finding that differences in electrical potential across the plane of the substrate, induced by electrode edges such as the boundaries of the metallization or the transparent conductive oxide, can play a primary role in behaviour and degradation across a wide range of stability tests. In particular, we observe clear signatures of lateral ion migration in solar cells made using both double and triple cation mixed-halide perovskites, with effects induced by reverse-bias stress, illuminated MPP-tracking, and even as a result of time spent in storage. In their mildest form these effects manifest as patterns of modulated photoluminescence intensity around device boundaries that propagate into surrounding regions as a function of applied bias and time. We show that ionic drift-diffusion models provide a convincing match to these patterns, including their voltage dependence. In the context of MPP-tracking, we observe a severe form of material degradation in our solar cells whose spatial distribution and voltage dependence match models of lateral ion migration with high accuracy. We thereby obtain evidence of an ionically-mediated degradation mode which proceeds at a high rate near device boundaries, but is nonetheless also operative throughout the active area. This connection between "bulk" and "boundary" degradation has multiple implications for both the design of perovskite solar cell and LED devices, as well as for the understanding of their characteristic behaviour in long-term stability testing.

Radio Frequency Interference (RFI) is one of the systematic challenges preventing 21cm interferometric instruments from detecting the Epoch of Reionization. To mitigate the effects of RFI on data analysis pipelines, numerous inpaint techniques have been developed to restore RFI corrupted data. We examine the qualitative and quantitative errors introduced into the visibilities and power spectrum due to inpainting. We perform our analysis on simulated data as well as real data from the Hydrogen Epoch of Reionization Array (HERA) Phase 1 upper limits. We also introduce a convolutional neural network that capable of inpainting RFI corrupted data in interferometric instruments. We train our network on simulated data and show that our network is capable at inpainting real data without requiring to be retrained. We find that techniques that incorporate high wavenumbers in delay space in their modeling are best suited for inpainting over narrowband RFI. We also show that with our fiducial parameters Discrete Prolate Spheroidal Sequences (DPSS) and CLEAN provide the best performance for intermittent ``narrowband'' RFI while Gaussian Progress Regression (GPR) and Least Squares Spectral Analysis (LSSA) provide the best performance for larger RFI gaps. However we caution that these qualitative conclusions are sensitive to the chosen hyperparameters of each inpainting technique. We find these results to be consistent in both simulated and real visibilities. We show that all inpainting techniques reliably reproduce foreground dominated modes in the power spectrum. Since the inpainting techniques should not be capable of reproducing noise realizations, we find that the largest errors occur in the noise dominated delay modes. We show that in the future, as the noise level of the data comes down, CLEAN and DPSS are most capable of reproducing the fine frequency structure in the visibilities of HERA data., Comment: 21 pages, 13 figures

We introduce CALAMITY, a precision bandpass calibration method for radio interferometry. CALAMITY can solve for direction independent gains with arbitrary frequency structure to the high precision required for 21 cm cosmology with minimal knowledge of foregrounds or antenna beams and does not require any degree of redundancy (repeated identical measurements of the same baseline). We have achieved this through two key innovations. Firstly, we model the foregrounds on each baseline independently using a flexible and highly efficient set of basis functions that have minimal overlap with 21 cm modes and enforce spectral smoothness in the calibrated foregrounds. Secondly, we use an off-the-shelf GPU accelerated API (TENSORFLOW) to solve for per-baseline foregrounds simultaneously with per-frequency antenna gains in a single optimization loop. GPU acceleration is critical for our technique to be able to solve for the large numbers of foreground and gain parameters simultaneously across all frequencies for an interferometer with $\gtrsim 10$ antennas in a reasonable amount of time. In this paper, we give an overview of our technique and using realistic simulations and demonstrate its performance in solving for and removing pathological gain structures to the level necessary to measure fluctuations in the 21 cm emission field from Hydrogen gas during the Cosmic Dawn and Reionization. If you want to start using CALAMITY now, you can find a tutorial notebook at https://github.com/aewallwi/calamity/blob/main/examples/Calamity_Tutorial.ipynb ., 19 pages, 13 figures, comments welcome. Replacement incorporates minor corrections in response to community feedback. Submitted to ApJ

We present a framework for identifying and flagging malfunctioning antennas in large radio interferometers. We outline two distinct categories of metrics designed to detect outliers along known failure modes of large arrays: cross-correlation metrics, based on all antenna pairs, and auto-correlation metrics, based solely on individual antennas. We define and motivate the statistical framework for all metrics used, and present tailored visualizations that aid us in clearly identifying new and existing systematics. We implement these techniques using data from 105 antennas in the Hydrogen Epoch of Reionization Array (HERA) as a case study. Finally, we provide a detailed algorithm for implementing these metrics as flagging tools on real data sets., Comment: 31 pages, 17 figures

Partial shading can trigger permanent damage in photovoltaic modules because the illuminated solar cells drive the shaded cells into reverse bias. Under reverse bias conditions, perovskite solar cells have been shown to degrade quickly due to processes that have so far remained elusive. Here, we combine optical, microstructural, and electrical characterization to address the mechanisms governing perovskite solar cell degradation under reverse bias. Three main processes are shown to occur in cesium/formamidinium lead iodide/bromide cells depending on the reverse voltage applied, the duration of the reverse bias treatment and the cell structure. The first and most severe involves the formation of highly conductive shunts, preferentially in regions covered by the metal electrode (with apparently equal propensity for various metals) and, at higher reverse voltages, within the perovskite active area. Second, we find that iodide is reversibly driven into the organic electron transport layer, causing an S-shape in the current–voltage curve and lowering power conversion efficiency. Finally, under heavy reverse biasing the perovskite absorber is shown to degrade into iodide- and bromide-rich sub-layers, an irreversible process associated with a shift in the effective band gap and changes to the perovskite microstructure. Criteria that must be met to pass partial shading tests defined by the International Electrotechnical Commission are also discussed in relation to these issues, indicating the urgent need for device structures far more robust than those usually reported.

The key challenge in the observation of the redshifted 21-cm signal from cosmic reionization is its separation from the much brighter foreground emission. Such separation relies on the different spectral properties of the two components, although, in real life, the foreground intrinsic spectrum is often corrupted by the instrumental response, inducing systematic effects that can further jeopardize the measurement of the 21-cm signal. In this paper, we use Gaussian Process Regression to model both foreground emission and instrumental systematics in $\sim 2$ hours of data from the Hydrogen Epoch of Reionization Array. We find that a simple co-variance model with three components matches the data well, giving a residual power spectrum with white noise properties. These consist of an "intrinsic" and instrumentally corrupted component with a coherence-scale of 20 MHz and 2.4 MHz respectively (dominating the line of sight power spectrum over scales $k_{\parallel} \le 0.2$ h cMpc$^{-1}$) and a baseline dependent periodic signal with a period of $\sim 1$ MHz (dominating over $k_{\parallel} \sim 0.4 - 0.8$h cMpc$^{-1}$) which should be distinguishable from the 21-cm EoR signal whose typical coherence-scales is $\sim 0.8$ MHz., 15 pages, 15 figures, 1 table, Accepted to MNRAS

Nearly 1 in every 120 children born has a congenital heart defect. Although surgical therapy has improved survival, many of these children go on to develop right ventricular heart failure (RVHF). The emergence of cardiovascular regenerative medicine as a potential therapeutic strategy for pediatric HF has provided new avenues for treatment with a focus on repairing or regenerating the diseased myocardium to restore cardiac function. Although primarily tried using adult cells and adult disease models, stem cell therapy is relatively untested in the pediatric population. Here, we investigate the ability of electrical stimulation (ES) to enhance the retention and therapeutic function of pediatric cardiac-derived c-kit+ progenitor cells (CPCs) in an animal model of RVHF. Human CPCs isolated from pediatric patients were exposed to chronic ES and implanted into the RV myocardium of rats. Cardiac function and cellular retention analysis showed electrically stimulated CPCs (ES-CPCs) were retained in the heart at a significantly higher level and longer time than control CPCs and also significantly improved right ventricular functional parameters. ES also induced upregulation of extracellular matrix and adhesion genes and increased in vitro survival and adhesion of cells. Specifically, upregulation of β1 and β5 integrins contributed to the increased retention of ES-CPCs. Lastly, we show that ES induces CPCs to release higher levels of pro-reparative factors in vitro. These findings suggest that ES can be used to increase the retention, survival, and therapeutic effect of human c-kit+ progenitor cells and can have implications on a variety of cell-based therapies. Stem Cells 2019;37:1528–1541

Background Surgical management of appendiceal carcinoid tumors is heavily debated, despite National Comprehensive Cancer Network guidelines recommending aggressive resection of tumors >2 cm. We investigated national practice patterns and the predictors and impact of guideline non-adherence. Study Design The National Cancer Database was queried for cases of appendiceal carcinoids diagnosed from 2004 to 2015 treated with either appendectomy or hemicolectomy. Multivariable logistic regression, adjusted for demographic and clinical factors, identified associations with the procedure type among patients stratified by tumor size ≤2 cm and >2 cm. Cox Proportional Hazards then identified associations with overall survival among stratified patient groups. Results Of 3,198 cases of appendiceal carcinoids, 1,893 appendectomies and 1,305 hemicolectomies were identified. Contrary to National Comprehensive Cancer Network guidelines, 32.4% of tumors ≤2 cm were treated with hemicolectomy and 31.3% of tumors >2 cm were treated with definitive appendectomy. Hemicolectomy for small tumors was associated with age 65 years and older (odds ratio [OR] 2.4; 95% CI 1.7 to 3.3; reference group age 18 to 39 years), history of malignancy (OR 2.0; 95% CI 1.6 to 2.6), tumor size 1.1 to 2 cm (OR 2.8; 95% CI 2.3 to 3.4; reference group size ≤1 cm), and lymphovascular invasion (OR 2.2; 95% CI 1.6 to 3.2); appendectomy for large tumors was associated with age 65 years and older only (OR 2.2; 95% CI 1.1 to 4.2). Procedure type was not associated with survival for small or large tumors (hazard ratio 1.0; 95% CI 0.7 to 1.4 and hazard ratio 1.1; 95% CI 0.6 to 2.0, respectively). Conclusions Despite well-known size-based treatment guidelines for appendiceal carcinoids, one-third of patients in the US undergo hemicolectomy for small tumors and appendectomy for large tumors. Guideline non-adherence, however, is not associated with overall survival. Reasons for these practice patterns should be explored, and guidelines revisited.

BackgroundSelf-paced treadmills (SPT) can provide an engaging setting for gait rehabilitation by responding directly to the user’s intent to modulate the external environment and internal effort. They also can improve gait analyses by allowing scientists and clinicians to directly measure the effect of an intervention on walking velocity. Unfortunately, many common SPT algorithms are not suitable for individuals with gait impairment because they are designed for symmetric gait patterns. When the user’s gait is asymmetric due to paresis or if it contains large accelerations, the performance is diminished. Creating and validating an SPT that is suitable for asymmetric gait will improve our ability to study rehabilitation interventions in populations with gait impairment. The objective of this study was to test and validate a novel self-paced treadmill on both symmetric and asymmetric gait patterns and evaluate differences in gait kinematics, kinetics, and muscle activity between fixed-speed and self-paced treadmill walking.MethodsWe collected motion capture, ground reaction force data, and muscle activity from 6 muscles in the dominant leg during walking from 8 unimpaired subjects. In the baseline condition, the subjects walked at 3 fixed-speeds normalized to their leg length as Froude numbers. We developed a novel kinematic method for increasing the accuracy of the user’s estimated walking velocity and compared our method against other published algorithms at each speed. Afterward, subjects walked on the SPT while matching their walking speed to a given target velocity using visual feedback of the treadmill speed. We evaluated the SPT by measuring steady-state error and the number of steps to reach the desired speed. We split the gait cycle into 7 phases and compared the kinematic, kinetic, and muscle activity between the fixed speed and self-paced mode in each phase. Then, we validated the performance of the SPT for asymmetric gait by having subjects walk on the SPT while wearing a locked-knee brace set to 0° on the non-dominant leg.ResultsOur SPT enabled controlled walking for both symmetric and asymmetric gait patterns. Starting from rest, subjects were able to control the SPT to reach the targeted speeds using visual feedback in 13–21 steps. With the locked knee brace, subjects controlled the treadmill with substantial step length and step velocity asymmetry. One subject was able to execute a step-to gait and halt the treadmill on heel-strikes with the braced leg. Our kinematic correction for step-length outperformed the competing algorithms by significantly reducing the velocity estimation error at the tested velocities. The joint kinematics, joint torques, and muscle activity were generally similar between fixed-speed and self-paced walking. Statistically significant differences were found in 5 of 63 tests for joint kinematics, 2 of 63 tests for joint torques, and 9 of 126 tests for muscle activity. The differences that were statistically significant were not found across all speeds and were generally small enough to be of limited clinical relevance.ConclusionsWe present a validated method for implementing a self-paced treadmill for asymmetric and symmetric gaits. As a result of the increased accuracy of our estimation algorithm, our SPT produced controlled walking without including a position feedback controller, thereby reducing the influence of the controller on measurements of the user’s true walking speed. Our method relies only on a kinematic correction to step length and step time which can support transfer to systems outside of the laboratory for symmetric and asymmetric gaits in clinical populations.

Observations in the lowest MWA band between $75-100$ MHz have the potential to constrain the distribution of neutral hydrogen in the intergalactic medium at redshift $\sim 13-17$. Using 15 hours of MWA data, we analyse systematics in this band such as radio-frequency interference (RFI), ionospheric and wide field effects. By updating the position of point sources, we mitigate the direction independent calibration error due to ionospheric offsets. Our calibration strategy is optimized for the lowest frequency bands by reducing the number of direction dependent calibrators and taking into account radio sources within a wider field of view. We remove data polluted by systematics based on the RFI occupancy and ionospheric conditions, finally selecting 5.5 hours of the cleanest data. Using these data, we obtain two sigma upper limits on the 21 cm power spectrum in the range of $0.1\lessapprox k \lessapprox 1 ~\rm ~h~Mpc^{-1}$ and at $z$=14.2, 15.2 and 16.5, with the lowest limit being $6.3\times 10^6 ~\rm mK^2$ at $\rm k=0.14 \rm ~h~Mpc^{-1}$ and at $z=15.2$ with a possibility of a few \% of signal loss due to direction independent calibration., Comment: 17 pages, 18 figures, accepted to MNRAS

Current attempts to measure the 21cm Power Spectrum of neutral hydrogen during the Epoch of Reionization are limited by systematics which produce measured upper limits above both the thermal noise and the expected cosmological signal. These systematics arise from a combination of observational, instrumental, and analysis effects. In order to further understand and mitigate these effects, it is instructive to explore different aspects of existing datasets. One such aspect is the choice of observing field. To date, MWA EoR observations have largely focused on the EoR0 field. In this work, we present a new detailed analysis of the EoR1 field. The EoR1 field is one of the coldest regions of the Southern radio sky, but contains the very bright radio galaxy Fornax-A. The presence of this bright extended source in the primary beam of the interferometer makes the calibration and analysis of EoR1 particularly challenging. We demonstrate the effectiveness of a recently developed shapelet model of Fornax-A in improving the results from this field. We also describe and apply a series of data quality metrics which identify and remove systematically contaminated data. With substantially improved source models, upgraded analysis algorithms and enhanced data quality metrics, we determine EoR power spectrum upper limits based on analysis of the best $\sim$14-hours data observed during 2015 and 2014 at redshifts 6.5, 6.8 and 7.1, with the lowest $2\sigma$ upper limit at z=6.5 of $\Delta^2 \leq (73.78 ~\mathrm{mK)^2}$ at $k=0.13~\mathrm{h~ Mpc^{-1}}$, improving on previous EoR1 measurement results., Comment: 18 pages, 17 figures, Accepted for publication in MNRAS

Precise measurements of the 21 cm power spectrum are crucial for understanding the physical processes of hydrogen reionization. Currently, this probe is being pursued by low-frequency radio interferometer arrays. As these experiments come closer to making a first detection of the signal, error estimation will play an increasingly important role in setting robust measurements. Using the delay power spectrum approach, we have produced a critical examination of different ways that one can estimate error bars on the power spectrum. We do this through a synthesis of analytic work, simulations of toy models, and tests on small amounts of real data. We find that, although computed independently, the different error bar methodologies are in good agreement with each other in the noise-dominated regime of the power spectrum. For our preferred methodology, the predicted probability distribution function is consistent with the empirical noise power distributions from both simulated and real data. This diagnosis is mainly in support of the forthcoming HERA upper limit, and also is expected to be more generally applicable., Comment: 35 Pages, 9 Figures, 4 Tables. Replaced with accepted ApJ version; some clarifying text added in response to referee comments with no changes to results

As current- and next-generation astronomical instruments come online, they will generate an unprecedented deluge of data. Analyzing these data in real time presents unique conceptual and computational challenges, and their long-term storage and archiving is scientifically essential for generating reliable, reproducible results. We present here the real-time processing (RTP) system for the Hydrogen Epoch of Reionization Array (HERA), a radio interferometer endeavoring to provide the first detection of the highly redshifted 21 cm signal from Cosmic Dawn and the Epoch of Reionization by an interferometer. The RTP system consists of analysis routines run on raw data shortly after they are acquired, such as calibration and detection of radio-frequency interference (RFI) events. RTP works closely with the Librarian, the HERA data storage and transfer manager which automatically ingests data and transfers copies to other clusters for post-processing analysis. Both the RTP system and the Librarian are public and open source software, which allows for them to be modified for use in other scientific collaborations. When fully constructed, HERA is projected to generate over 50 terabytes (TB) of data each night, and the RTP system enables the successful scientific analysis of these data., Comment: 15 pages, 3 figures, published in Astronomy and Computing