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Measuring the escape fraction, f esc, of ionizing, Lyman continuum (Ly C) radiation is key to our understanding of the process of cosmic reionization. In this paper, we provide a methodology for recovering the posterior probability distribution of the Ly C escape fraction, |$f_{\rm esc}^{\rm PDF}$|⁠ , considering both the observational uncertainties and ensembles of simulated transmission functions through the intergalactic medium (IGM). We present an example of this method applied to a VUDS galaxy at z = 3.64 and find |$f_{\rm esc}^{\rm PDF}$| = 0.51 |$^{+0.33}_{-0.34}$| and compare this to the values computed assuming averaged IGM transmission with and without consideration of detection bias along average sightlines yielding |$f_{\rm esc}^{\langle T \rangle }$| = 1.40 |$^{+0.80}_{-0.42}$| and |$f_{\rm esc}^{\rm bias}$| = 0.82 |$^{+0.33}_{-0.16}$|⁠. Our results highlight the limitations of methods assuming average, smooth transmission functions. We also present MOSFIRE data for a sample of seven Ly C candidates selected based on photometric redshifts at z > 3.4, but find that all seven have overestimated photometric redshifts by Δ z ∼ 0.2 making them unsuitable for Ly C measurements. This results likely due to a bias induced by our selection criteria. [ABSTRACT FROM AUTHOR]

In this work, we investigate upper limits on the global escape fraction of ionizing photons (⁠|$f_{\rm esc/global}^{\rm abs}$|⁠) from a sample of galaxies probed for Lyman-continuum (LyC) emission characterized as non-LyC and LyC leakers. We present a sample of nine clean non-contaminated (by low-redshift interlopers, CCD problems, and internal reflections of the instrument) galaxies that do not show significant (>3σ) LyC flux in the range 880 < λrest < 910 Å. The nine-galaxy stacked spectrum reveals no significant LyC flux with an upper limit of |$f_{\rm esc}^{\rm abs} \le 0.06$|⁠. In the next step of our analysis, we join all estimates of |$f_{\rm esc}^{\rm abs}$| upper limits derived from different samples of 2 ≲  z < 6 galaxies from the literature reported in last ∼20 yr and include the sample presented in this work. We find the |$f_{\rm esc}^{\rm abs}$| upper limit ≤0.084 for the galaxies recognized as non-LyC leakers. After including all known detections from literature |$f_{\rm esc/global}^{\rm abs}$| upper limit ≤0.088 for all galaxies examined for LyC flux. Furthermore, |$f_{\rm esc}^{\rm abs}$| upper limits for different groups of galaxies indicate that the strongest LyC emitters could be galaxies classified as Lyman α emitters. We also discuss the possible existence of a correlation among the observed flux density ratio |$(F_{\nu }^{\mathrm{ LyC}}/F_{\nu }^{\mathrm{ UV}})_{\rm obs}$| and Lyman α equivalent width EW(Lyα), where we confirm the existence of moderately significant correlation among galaxies classified as non-LyC leakers. [ABSTRACT FROM AUTHOR]

Identifying non-contaminated sample of high-redshift galaxies with escaping Lyman continuum (LyC) flux is important for understanding the sources and evolution of cosmic reionization. We present CLAUDS (CFHT Large Area u -band deep survey) u -band photometry of the COSMOS field to probe LyC radiation from spectroscopically confirmed galaxies at |$z$| ≥ 3.5 and outside the standard Lyman-break galaxy colour-selection expectations. Complementary to the CLAUDS data, we use Subaru multifilter photometry, Hubble Space Telescope (HST) multifilter imaging, and the spectroscopic surveys D10K, VUDS, and 3D-HST. We present a sample of Lyman continuum galaxy (LCG) candidates in the redshift range 3.5 ≲ |$z$| ≲ 5.1. Here, we introduce 5 LCG candidates, where two are flagged quality 1 and three quality 2. The estimated |$f_{\rm esc}^{\rm abs}$| for quality 1 candidates are in the range |$\sim 5 - 73{{\ \rm per\ cent}}$| and |$\sim 30 - 93{{\ \rm per\ cent}}$|⁠. These estimates are based on our derived parameters from individual galaxies as inputs to a range of BPASS models as well as mean intergalactic medium (IGM) and maximal intergalactic and circumgalactic media (IGM+CGM) transmission. We conclude that our search for LCGs is most likely biased to lines of sight with low H  i densities or free from Lyman limit systems. Our two best LCG candidates have EW (Lyα) ≤ 50 Å and we find no correlation or anticorrelation between EW (Lyα), |$f_{\rm esc}^{\rm abs}$|⁠ , and R obs, the ratio of ionizing to non-ionizing observed flux in the measured passbands. Stacking candidates without solid LyC detections (S/N < 3) results in an estimated |$f_{\rm esc}^{\rm abs}$| from galaxies not greater than |$1{{\ \rm per\ cent}}$|⁠. [ABSTRACT FROM AUTHOR]

A study of a series of progressively aligned metal particle tape samples has been undertaken. Our data indicates that increasing the orientation, desirable for better recording performance, has been found to increase thermal effects at both DC and high frequencies. The implications of this are that larger head fields are required to write high frequency transitions on more aligned media. The experimental results are compared to the switching model suggested by el Hilo to determine the thermal stability factor [KV.sub.m]/kT of the samples. Index Terms--interactions, magnetisation reversal, metal particles, orientation, pulsed magnetic fields, thermal stability

This work describes an experimental study which reviews the various techniques that can be used for determination of anisotropy fields in recording media. At the present time this topic is of considerable importance due to the need to understand the detailed mechanisms of magnetization reversal and the factors that control the switching field distribution in recording media. We have used a metal-particle-based tape material and have employed various magnetic techniques for the determination of the apparent anisotropy field, H[sub K]. The techniques included hysteresis loops measured in a direction transverse to the texture direction of the tapes, single-point detection in the successive derivatives of the magnetization with respect to the field, transverse susceptibility measurement, and the variation of the bulk coercivity with temperature. We find the temperature variation of coercivity produces values of H[sub K] far smaller than values determined by other methods due to orientation effects. General agreement is seen for the other techniques mentioned and results for samples with differing degrees of texture show that the apparent anisotropy field of the grains as measured by these techniques is influenced greatly by orientation effects. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Objectives: In the United States, end-stage kidney disease (ESKD) is responsible for high mortality and significant healthcare costs, with the number of cases sharply increasing in the past 2 decades. In this study, we aimed to reduce these impacts by developing an ESKD model for predicting its occurrence in a 2-year period., Materials and Methods: We developed a machine learning (ML) pipeline to test different models for the prediction of ESKD. The electronic health record was used to capture several kidney disease-related variables. Various imputation methods, feature selection, and sampling approaches were tested. We compared the performance of multiple ML models using area under the ROC curve (AUCROC), area under the Precision-Recall curve (PR-AUC), and Brier scores for discrimination, precision, and calibration, respectively. Explainability methods were applied to the final model., Results: Our best model was a gradient-boosting machine with feature selection and imputation methods as additional components. The model exhibited an AUCROC of 0.97, a PR-AUC of 0.33, and a Brier score of 0.002 on a holdout test set. A chart review analysis by expert physicians indicated clinical utility., Discussion and Conclusion: An ESKD prediction model can identify individuals at risk for ESKD and has been successfully deployed within our health system., Competing Interests: The authors declare no competing interests., (© The Author(s) 2024. Published by Oxford University Press on behalf of the American Medical Informatics Association.)

Convalescent plasma (CP) is widely used to treat COVID-19, but without formal evidence of efficacy. Here, we report the beneficial effects of CP in a severely ill COVID-19 patient with prolonged pneumonia and advanced chronic lymphocytic leukemia (CLL), who was unable to generate an antiviral antibody response of her own. On day 33 after becoming symptomatic, the patient received CP containing high-titer (ID 50 > 5,000) neutralizing antibodies (NAbs), defervesced, and improved clinically within 48 h and was discharged on day 37. Hence, when present in sufficient quantities, NAbs to SARS-CoV-2 have clinical benefit even if administered relatively late in the disease course. However, analysis of additional CP units revealed widely varying NAb titers, with many recipients exhibiting endogenous NAb responses far exceeding those of the administered units. To obtain the full therapeutic benefits of CP immunotherapy, it will thus be important to determine the neutralizing activity in both CP units and transfusion candidates., Competing Interests: R.S.D. and K.H. have submitted an intellectual property disclosure related to the ACE2/RBD assay., (© 2020 The Author(s).)

Activation of the phagocytic NADPH oxidase-2 (NOX-2) in neutrophils is a critical process in the innate immune system and is associated with elevated local concentrations of superoxide, hydrogen peroxide (H2O2) and hypochlorous acid. Under pathological conditions, NOX-2 activity has been implicated in the development of autoimmunity, indicating a role in modulating lymphocyte effector function. Notably, T-cell clonal expansion and subsequent cytokine production requires a metabolic switch from mitochondrial respiration to aerobic glycolysis. Previous studies demonstrate that H2O2 generated from activated neutrophils suppresses lymphocyte activation but the mechanism is unknown. We hypothesized that activated neutrophils would prevent the metabolic switch and suppress the effector functions of T-cells through a H2O2-dependent mechanism. To test this, we developed a model co-culture system using freshly isolated neutrophils and lymphocytes from healthy human donors. Extracellular flux analysis was used to assess mitochondrial and glycolytic activity and FACS analysis to assess immune function. The neutrophil oxidative burst significantly inhibited the induction of lymphocyte aerobic glycolysis, caused inhibition of oxidative phosphorylation and suppressed lymphocyte activation through a H2O2-dependent mechanism. Hydrogen peroxide and a redox cycling agent, DMNQ, were used to confirm the impact of H2O2 on lymphocyte bioenergetics. In summary, we have shown that the lymphocyte metabolic switch from mitochondrial respiration to glycolysis is prevented by the oxidative burst of neutrophils. This direct inhibition of the metabolic switch is then a likely mechanism underlying the neutrophil-dependent suppression of T-cell effector function., (© 2015 Authors; published by Portland Press Limited.)