Structure/Function Analysis of Nonwoven Cotton Topsheet Fabrics: Multi-Fiber Blending Effects on Fluid Handling and Fabric Handle Mechanics

Greige cotton (GC) has attracted interest in recent years as an eco-friendly, functional fiber for use in nonwoven topsheet materials. GC imparts favorable fluid management and sensorial properties associated with urinary liquid transport and indices related to comfort in wearable incontinence nonwovens. Nonwoven GC has material surface polarity, an ambient moisture content, and a lipid/polysaccharide matrix that imparts positive fluid mechanic properties applicable to incontinence management topsheet materials. However, a better understanding of the connection between functionality and compositional aspects of molecular, mechanical, and material property relations is still required to employ structure/function relations beyond a priori design. Thus, this study focuses on the relation of key indices of material fluid and sensorial functions to nonwoven topsheet composition. Greige cotton, polypropylene, bleached cotton, and polyester fiber blends were hydroentangled at 60, 80, and 100 bar. Greige cotton polypropylene and bleached cotton were blended at ratios to balance surface polarity, whereas low percentages of polyester were added to confer whiteness properties. Electrokinetic and contact angle measurements were obtained for the hydroentangled nonwovens to assess surface polarity in light of material composition. Notably, materials demonstrated a relation of hydrophobicity to swelling as determined electrokinetically by Δζ, ζplateau, and contact angles greater than 90°. Subsequently, three blended nonwoven fabrics were selected to assess effects on fluid management properties including topsheet performance indices of rewet, strikethrough, and fluid handling (rate and efficiency of transport to the absorbent core). These materials aligned well with commercial topsheet fluid mechanics. Using the Leeds University Fabric Handle Evaluation System (LUFHES), the nonwovens were tested for total fabric hand. The results of the LUFHES measurements are discussed in light of fiber contributions. Fiber ratios were found to correlate well with improvement in softness, flexibility, and formability. This study provides insights that improves the understanding of the multifunctional properties accessible with greige cotton toward decisions valuable to selecting greige cotton as an environmentally friendly fiber for nonwoven topsheets

Extragalactic Radio Continuum Surveys and the Transformation of Radio Astronomy

Next-generation radio surveys are about to transform radio astronomy by discovering and studying tens of millions of previously unknown radio sources. These surveys will provide new insights to understand the evolution of galaxies, measuring the evolution of the cosmic star formation rate, and rivalling traditional techniques in the measurement of fundamental cosmological parameters. By observing a new volume of observational parameter space, they are also likely to discover unexpected new phenomena. This review traces the evolution of extragalactic radio continuum surveys from the earliest days of radio astronomy to the present, and identifies the challenges that must be overcome to achieve this transformational change.Comment: To be published in Nature Astronomy 18 Sept 201

Genes Important for Catalase Activity in Enterococcus faecalis

Little in general is known about how heme proteins are assembled from their constituents in cells. The Gram-positive bacterium Enterococcus faecalis cannot synthesize heme and does not depend on it for growth. However, when supplied with heme in the growth medium the cells can synthesize two heme proteins; catalase (KatA) and cytochrome bd (CydAB). To identify novel factors important for catalase biogenesis libraries of E. faecalis gene insertion mutants were generated using two different types of transposons. The libraries of mutants were screened for clones deficient in catalase activity using a colony zymogram staining procedure. Analysis of obtained clones identified, in addition to katA (encoding the catalase enzyme protein), nine genes distributed over five different chromosomal loci. No factors with a dedicated essential role in catalase biogenesis or heme trafficking were revealed, but the results indicate the RNA degradosome (srmB, rnjA), an ABC-type oligopeptide transporter (oppBC), a two-component signal transducer (etaR), and NADH peroxidase (npr) as being important for expression of catalase activity in E. faecalis. It is demonstrated that catalase biogenesis in E. faecalis is independent of the CydABCD proteins and that a conserved proline residue in the N-terminal region of KatA is important for catalase assembly

Noise Contributions in an Inducible Genetic Switch: A Whole-Cell Simulation Study

Stochastic expression of genes produces heterogeneity in clonal populations of bacteria under identical conditions. We analyze and compare the behavior of the inducible lac genetic switch using well-stirred and spatially resolved simulations for Escherichia coli cells modeled under fast and slow-growth conditions. Our new kinetic model describing the switching of the lac operon from one phenotype to the other incorporates parameters obtained from recently published in vivo single-molecule fluorescence experiments along with in vitro rate constants. For the well-stirred system, investigation of the intrinsic noise in the circuit as a function of the inducer concentration and in the presence/absence of the feedback mechanism reveals that the noise peaks near the switching threshold. Applying maximum likelihood estimation, we show that the analytic two-state model of gene expression can be used to extract stochastic rates from the simulation data. The simulations also provide mRNA–protein probability landscapes, which demonstrate that switching is the result of crossing both mRNA and protein thresholds. Using cryoelectron tomography of an E. coli cell and data from proteomics studies, we construct spatial in vivo models of cells and quantify the noise contributions and effects on repressor rebinding due to cell structure and crowding in the cytoplasm. Compared to systems without spatial heterogeneity, the model for the fast-growth cells predicts a slight decrease in the overall noise and an increase in the repressors rebinding rate due to anomalous subdiffusion. The tomograms for E. coli grown under slow-growth conditions identify the positions of the ribosomes and the condensed nucleoid. The smaller slow-growth cells have increased mRNA localization and a larger internal inducer concentration, leading to a significant decrease in the lifetime of the repressor–operator complex and an increase in the frequency of transcriptional bursts

Key mechanisms governing resolution of lung inflammation

Innate immunity normally provides excellent defence against invading microorganisms. Acute inflammation is a form of innate immune defence and represents one of the primary responses to injury, infection and irritation, largely mediated by granulocyte effector cells such as neutrophils and eosinophils. Failure to remove an inflammatory stimulus (often resulting in failed resolution of inflammation) can lead to chronic inflammation resulting in tissue injury caused by high numbers of infiltrating activated granulocytes. Successful resolution of inflammation is dependent upon the removal of these cells. Under normal physiological conditions, apoptosis (programmed cell death) precedes phagocytic recognition and clearance of these cells by, for example, macrophages, dendritic and epithelial cells (a process known as efferocytosis). Inflammation contributes to immune defence within the respiratory mucosa (responsible for gas exchange) because lung epithelia are continuously exposed to a multiplicity of airborne pathogens, allergens and foreign particles. Failure to resolve inflammation within the respiratory mucosa is a major contributor of numerous lung diseases. This review will summarise the major mechanisms regulating lung inflammation, including key cellular interplays such as apoptotic cell clearance by alveolar macrophages and macrophage/neutrophil/epithelial cell interactions. The different acute and chronic inflammatory disease states caused by dysregulated/impaired resolution of lung inflammation will be discussed. Furthermore, the resolution of lung inflammation during neutrophil/eosinophil-dominant lung injury or enhanced resolution driven via pharmacological manipulation will also be considered

Shedding Light on the Galaxy Luminosity Function

From as early as the 1930s, astronomers have tried to quantify the statistical nature of the evolution and large-scale structure of galaxies by studying their luminosity distribution as a function of redshift - known as the galaxy luminosity function (LF). Accurately constructing the LF remains a popular and yet tricky pursuit in modern observational cosmology where the presence of observational selection effects due to e.g. detection thresholds in apparent magnitude, colour, surface brightness or some combination thereof can render any given galaxy survey incomplete and thus introduce bias into the LF. Over the last seventy years there have been numerous sophisticated statistical approaches devised to tackle these issues; all have advantages -- but not one is perfect. This review takes a broad historical look at the key statistical tools that have been developed over this period, discussing their relative merits and highlighting any significant extensions and modifications. In addition, the more generalised methods that have emerged within the last few years are examined. These methods propose a more rigorous statistical framework within which to determine the LF compared to some of the more traditional methods. I also look at how photometric redshift estimations are being incorporated into the LF methodology as well as considering the construction of bivariate LFs. Finally, I review the ongoing development of completeness estimators which test some of the fundamental assumptions going into LF estimators and can be powerful probes of any residual systematic effects inherent magnitude-redshift data.Comment: 95 pages, 23 figures, 3 tables. Now published in The Astronomy & Astrophysics Review. This version: bring in line with A&AR format requirements, also minor typo corrections made, additional citations and higher rez images adde

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Initial results of coring at Prees, Cheshire Basin, UK (ICDP JET project): towards an integrated stratigraphy, timescale, and Earth system understanding for the Early Jurassic

This is the final version. Available on open access from Copernicus Publications via the DOI in this recordData availability: Full core scan data (https://doi.org/10.5285/91392f09-25d4-454c-aece-56bde0dbf3ba, BGS Core Scanning Facility, 2022) will be available after 1 November 2024 via the Natural Environment Research Council (NERC) National Geoscience Data Centre (https://webapps.bgs.ac.uk/services/ngdc/accessions/index.html#, last access: 12 October 2023). Downhole logging data (https://doi.org/10.5880/ICDP.5065.001​​​​​​​, Wonik, 2023) will be made available via the ICDP (https://www.icdp-online.org/projects/by-continent/europe/jet-uk/, last access: 12 October 2023). The JET Operational Report is published as Hesselbo et al. (2023); full information about the operational dataset, the logging dataset, data availability and the explanatory remarks is available on the ICPD-JET project website: https://www.icdp-online.org/projects/by-continent/europe/jet-uk/ (last access: 12 October 2023). A subset of data, additional biostratigraphic tables, and vector graphics files for Figs. 3–5 are included as the Supplement. Supplementary Data File 1 tabulates the corrected depth scale for Prees 2C. Supplementary Data File 2 summarizes the ammonite-based chronostratigraphy of the Prees 2 cores (ammonite identifications by Kevin N. Page). Supplementary Data File 3 summarizes the ammonite-based chronostratigraphy for the Hettangian to Early Pliensbachian of the Llanbedr (Mochras Farm) borehole (updated by Kevin N. Page). Supplementary Data File 4 tabulates the organic carbon-isotope ratios, TOC, and carbonate content of low-resolution samples taken at the Prees drill site; TOC and carbonate data are calculated using calibration based on portable XRF (Supplementary Data File 5) and a gas source isotope ratio mass spectrometer (Supplementary Data File 6). Supplementary Data File 5 tabulates portable XRF results for bulk rock powders of low-resolution samples taken at the Prees drill site; uncertainties stated in the table are given for the fit to the raw data and do not reflect the true reproducibility of the data. Empty fields indicate values under the detection limit. Sample SSK116001 acted as a repeat sample which was measured 70 times over the course of the data acquisition to determine the repeatability and drift of the instrument. LE stands for “light elements”. Supplementary Data File 6 tabulates gas source isotope ratio mass spectrometry (GS-IRMS) data (oxygen- and carbon-isotope ratios of carbonate as well as carbonate content calculated as calcite) for a set of 24 samples covering the entire core length and reflecting a representative spread of carbonate content. Comparison of GS-IRMS data with p-XRF data was used to create a calibration curve to calculate the carbonate (and TOC) content of all low-resolution samples. Supplementary Data File 7 tabulates pyrolysis data (Rock-Eval 6) for Prees 1 well cuttings and Wilkesley borehole samples. Supplementary Data File 8 contains vector graphics files (.svg) for Figs. 3–5.Drilling for the International Continental Scientific Drilling Program (ICDP) Early Jurassic Earth System and Timescale project (JET) was undertaken between October 2020 and January 2021. The drill site is situated in a small-scale synformal basin of the latest Triassic to Early Jurassic age that formed above the major Permian–Triassic half-graben system of the Cheshire Basin. The borehole is located to recover an expanded and complete succession to complement the legacy core from the Llanbedr (Mochras Farm) borehole drilled through 1967–1969 on the edge of the Cardigan Bay Basin, North Wales. The overall aim of the project is to construct an astronomically calibrated integrated timescale for the Early Jurassic and to provide insights into the operation of the Early Jurassic Earth system. Core of Quaternary age cover and Early Jurassic mudstone was obtained from two shallow partially cored geotechnical holes (Prees 2A to 32.2 m below surface (m b.s.) and Prees 2B to 37.0 m b.s.) together with Early Jurassic and Late Triassic mudstone from the principal hole, Prees 2C, which was cored from 32.92 to 651.32 m (corrected core depth scale). Core recovery was 99.7 % for Prees 2C. The ages of the recovered stratigraphy range from the Late Triassic (probably Rhaetian) to the Early Jurassic, Early Pliensbachian (Ibex Ammonoid Chronozone). All ammonoid chronozones have been identified for the drilled Early Jurassic strata. The full lithological succession comprises the Branscombe Mudstone and Blue Anchor formations of the Mercia Mudstone Group, the Westbury and Lilstock formations of the Penarth Group, and the Redcar Mudstone Formation of the Lias Group. A distinct interval of siltstone is recognized within the Late Sinemurian of the Redcar Mudstone Formation, and the name “Prees Siltstone Member” is proposed. Depositional environments range from playa lake in the Late Triassic to distal offshore marine in the Early Jurassic. Initial datasets compiled from the core include radiography, natural gamma ray, density, magnetic susceptibility, and X-ray fluorescence (XRF). A full suite of downhole logs was also run. Intervals of organic carbon enrichment occur in the Rhaetian (Late Triassic) Westbury Formation and in the earliest Hettangian and earliest Pliensbachian strata of the Redcar Mudstone Formation, where up to 4 % total organic carbon (TOC) is recorded. Other parts of the succession are generally organic-lean, containing less than 1 % TOC. Carbon-isotope values from bulk organic matter have also been determined, initially at a resolution of ∼ 1 m, and these provide the basis for detailed correlation between the Prees 2 succession and adjacent boreholes and Global Stratotype Section and Point (GSSP) outcrops. Multiple complementary studies are currently underway and preliminary results promise an astronomically calibrated biostratigraphy, magnetostratigraphy, and chemostratigraphy for the combined Prees and Mochras successions as well as insights into the dynamics of background processes and major palaeo-environmental changes.ICDPNatural Environment Research Council (NERC)German Research FoundationHungarian Scientific Research FundNational Science Centre, PolandPolish Geological Institut

Can breastfeeding support be taught online? An evaluation of a training package for student health visitors

This study evaluated an online learning package developed to support student health visitors' education about health promotion in infant feeding and how best to support parents in the community. Online learning is increasingly being used in nursing education, in combination with traditional classroom-based teaching and experience in practice. To meet the needs of students across the South West of England, the University of the West of England (UWE) has developed innovative ways of delivering high-quality, evidence-based education. Study participants (n=66) were enrolled on a specialist community public health nursing course and were part of a cohort that studied at two geographically distant venues in the South West. Quantitative and qualitative data were collected using an online survey. The study found that students had the skills and ability to use the online programme, and enjoyed working at home at a self-directed time and pace. Expectations of online learning packages are high in terms of professional presentation and technological quality. While students accepted the concept of online learning, some felt it was not an appropriate method to deliver training about breastfeeding. This evaluation suggests that the majority of students accept online learning as part of a blended learning package, even for practice-based subjects such as breastfeeding promotion and support