Staphylococcus aureus is a leading cause of broad-spectrum infections both in the community and within healthcare settings. Methicillin-resistant Staphylococcus aureus (MRSA) has become a global ...public health issue. The aim of this study was to examine the clinical and molecular characteristics of Staphylococcus aureus isolates and to define the population structure and distribution of major MRSA clones isolated in a tertiary-care hospital in Mexico.
From April 2017 to April 2018, 191 Staphylococcus aureus isolates were collected. The frequency of MRSA was 26.7%; these strains exhibited resistance to clindamycin (84.3%), erythromycin (86.2%), levofloxacin (80.3%), and ciprofloxacin (86.3%). The majority of MRSA strains harbored the SCCmec type II (76.4%) and t895 (56.8%) and t9364 (11.7%) were the most common spa types in both hospital-associated MRSA and community-associated MRSA isolates. ST5-MRSA-II-t895 (New York /Japan clone) and ST1011-MRSA-II-t9364 (New York /Japan-Mexican Variant clone) were the most frequently identified clones. Furthermore, different lineages of Clonal Complexes 5 (85.4%) and 8 (8.3%) were predominantly identified in this study.
Our study provides valuable information about the epidemiology of MRSA in a city of the central region of Mexico, and this is the first report on the association between t895 and t9364 spa types and ST5 and ST1011 lineages, respectively. These findings support the importance of permanent surveillance of MRSA aimed to detect the evolutionary changes of the endemic clones and the emergence of new strains.
Context. The star formation rate (SFR) is one of the main parameters used to analyze the evolution of galaxies through time. The need for recovering the light reprocessed by dust commonly requires ...the use of low spatial resolution far-infrared data. Recombination line luminosities provide an alternative, although uncertain dust-extinction corrections based on narrowband imaging or long-slit spectroscopy have traditionally posed a limit to their applicability. Integral field spectroscopy (IFS) is clearly the way to overcome this kind of limitation. Aims. We obtain integrated Hα, ultraviolet (UV) and infrared (IR)-based SFR measurements for 272 galaxies from the CALIFA survey at 0.005 <z< 0.03 using single-band and hybrid tracers. We aim to determine whether the extinction-corrected Hα luminosities provide a good measure of the SFR and to shed light on the origin of the discrepancies between tracers. Updated calibrations referred to Hα are provided. The well-defined selection criteria and large statistics allow us to carry out this analysis globally and split by properties, including stellar mass and morphological type. Methods. We derive integrated, extinction-corrected Hα fluxes from CALIFA, UV surface and asymptotic photometry from GALEX and integrated WISE 22 μm and IRAS fluxes. Results. We find that the extinction-corrected Hα luminosity agrees with the hybrid updated SFR estimators based on either UV or Hα plus IR luminosity over the full range of SFRs (0.03−20 M⊙ yr-1). The coefficient that weights the amount of energy produced by newly-born stars that is reprocessed by dust on the hybrid tracers, aIR, shows a large dispersion. However, this coefficient does not became increasingly small at high attenuations, as expected if significant highly-obscured Hα emission were missed, i.e., after a Balmer decrement-based attenuation correction is applied. Lenticulars, early-type spirals, and type-2 AGN host galaxies show smaller coefficients because of the contribution of optical photons and AGN to dust heating. Conclusions. In the local Universe, the Hα luminosity derived from IFS observations can be used to measure SFR, at least in statistically-significant, optically-selected galaxy samples, once stellar continuum absorption and dust attenuation effects are accounted for. The analysis of the SFR calibrations by galaxies properties could potentially be used by other works to study the impact of different selection criteria in the SFR values derived, and to disentangle selection effects from other physically motivated differences, such as environmental or evolutionary effects.
Aims.
We aim to measure the Sloan
r
′, Sloan
i
′,
J
, and
Ks
magnitudes of Starlink’s STARLINK-1130 (Darksat) and STARLINK-1113 low Earth orbit (LEO) communication satellites and determine the ...effectiveness of the Darksat darkening treatment from the optical to the near-infrared (NIR).
Methods.
Four observations of Starlink’s LEO communication satellites, Darksat and STARLINK-1113, were conducted on two nights with two telescopes. The Chakana 0.6 m telescope at the Ckoirama observatory (Chile) observed both satellites on 5 Mar. 2020 (UTC) and 7 Mar. 2020 (UTC) using a Sloan
r
′ and Sloan
i
′ filter, respectively. The ESO VISTA 4.1 m telescope with the VIRCAM instrument observed both satellites on 5 Mar. 2020 (UTC) and 7 Mar. 2020 (UTC) in the NIR
J
-band and
Ks
-band, respectively.
Results.
The calibration, image processing, and analysis of the Darksat images give
r
≈ 5.6 mag,
i
≈ 5.0 mag,
J
≈ 4.2 mag, and
Ks
≈ 4.0 mag when scaled to a range of 550 km (airmass = 1) and corrected for the solar incidence and observer phase angles. In comparison, the STARLINK-1113 images give
r
≈ 4.9 mag,
i
≈ 4.4 mag,
J
≈ 3.8 mag, and
Ks
≈ 3.6 mag when corrected for range, solar incidence, and observer phase angles. The data and results presented in this work show that the special darkening coating used by Starlink for Darksat has darkened the Sloan
r
′ magnitude by 50%, Sloan
i
′ magnitude by 42%, NIR
J
magnitude by 32%, and NIR
Ks
magnitude by 28%.
Conclusions.
The results show that both satellites increase in reflective brightness with increasing wavelength and that the effectiveness of the darkening treatment is reduced at longer wavelengths. This shows that the mitigation strategies being developed by Starlink and other LEO satellite operators need to take into account other wavelengths, not just the optical. This work highlights the continued importance of obtaining multi-wavelength observations of many different LEO satellites in order to characterise their reflective properties and to aid the community in developing impact simulations and developing mitigation tools.
ABSTRACT
In this work, we present numerical simulations of Stream Interaction Regions (SIRs) and Corotating Interaction Regions (CIRs) using the sunrunner3d tool that employs as a coronal model the ...boundary conditions obtained by corhel/mas with the pluto code that describes the global 3D structure of the solar wind using the magnetohydrodynamics (MHD) approach in the inner heliosphere. Specifically, we selected a set of SIRs and CIRs observed by the Parker Solar Probe (PSP) and STEREO-A (STA) missions during the Carrington rotations (CRs) 2207 to 2210 and CRs from 2020 to 2022. In order to describe the dynamics of the plasma that constitutes the solar wind background conditions for the selected CRs, we solve the ideal MHD equations in an inertial frame of reference, managing the solar rotation by rotating the boundary values in ϕ (longitude) at a rate corresponding to the sidereal rotation rate of the solar equator. We show that our results using sunrunner3d can globally reproduce the plasma parameters, such as radial velocity, number proton density, and radial magnetic field strength of these large-scale structures, observed by PSP and STA at distances near the Sun and around 1 au, respectively. These results allow exploring the global evolution of SIRs/CIRs in the inner heliosphere using sunrunner3d.
Anti-reflective coatings are used in photovoltaic systems to minimize reflectance thus optimizing efficiency. Besides excellent optical properties, these coatings need to provide good mechanical ...properties due to hostile environmental conditions. Therefore, this study aims at designing anti-reflective coatings based upon multi-layers of TiO2 and SiO2 by magnetron sputtering on glass and silicon substrates at room temperature. Afterwards, these coatings were thermally annealed at 400, 500 and 600 °C to study the influence of such treatment on their optical and mechanical properties. Samples prepared at room temperature and annealed at 400 °C showed an optimized reflectance of about 2%. Advanced materials characterization techniques were used to elucidate the microstructural evolution of the multi-layers. The multi-layers annealed at 400 °C demonstrated a dense and smoothly packed microstructure with homogenous grains (50 nm in size), with a phase transformation from amorphous to anatase. In addition, exposure and damage of the glass substrate were detected for elevated temperatures (500 and 600 °C), thus increasing the reflectance. Nanoindentation revealed an improved hardness, elasticity, and resistance against plastic deformation for the sample annealed at 400 °C. Consequently, anti-reflective coatings with post-annealing treatment at 400 °C, unify two complementary aspects such as improved mechanical properties (extended durability) and enhanced collection abilities over a broader wavelength range (increased efficiency).
•Design of anti-reflective coatings (ARC) using TiO2/SiO2 multi-layers by DC/RF magnetron sputtering for photovoltaics.•In-situ optical emission spectroscopy verified reproducible process conditions.•Novel methodology to measure mechanical properties of thin films using XPM ultra-fast mode nanoindentation.•ARC with post-annealing improved mechanical properties and enhanced collection abilities.
•Areas with low educational attainment consistently experienced higher case rates•Population density was not significantly related to the prevalence of COVID-19•Movement of people made a significant ...contribution during the longer time period.•Highlights the significance of study timeframes for understanding social vulnerability.
COVID-19 has significantly and unevenly impacted the United States, disproportionately affecting socially vulnerable communities. While epidemiologists and public health officials have suggested social distancing and shelter-in-place orders to halt the spread of this virus, the ability to comply with these guidelines is dependent on neighborhood, household, and individual characteristics related to social vulnerability. We use structural equation modeling and multiple data sources, including anonymized mobile phone location data from SafeGraph, to examine the effects of different social vulnerability and built environment factors on COVID-19 prevalence over two overlapping time periods (March to May and March to November of 2020). We use Chicago, Illinois as a case study and find that zip codes with low educational attainment consistently experienced higher case rates over both periods. Though population density was not significantly related to the prevalence in any period, movement of people made a significant contribution only during the longer time period. This finding highlights the significance of analyzing different timeframes for understanding social vulnerability. Our results suggest social vulnerability played an influential role in COVID-19 prevalence, highlighting the needs to address socioeconomic barriers to pandemic recovery and future pandemic response.
Environmental exposures during early life play a critical role in life-course health, yet the molecular phenotypes underlying environmental effects on health are poorly understood. In the Human Early ...Life Exposome (HELIX) project, a multi-centre cohort of 1301 mother-child pairs, we associate individual exposomes consisting of >100 chemical, outdoor, social and lifestyle exposures assessed in pregnancy and childhood, with multi-omics profiles (methylome, transcriptome, proteins and metabolites) in childhood. We identify 1170 associations, 249 in pregnancy and 921 in childhood, which reveal potential biological responses and sources of exposure. Pregnancy exposures, including maternal smoking, cadmium and molybdenum, are predominantly associated with child DNA methylation changes. In contrast, childhood exposures are associated with features across all omics layers, most frequently the serum metabolome, revealing signatures for diet, toxic chemical compounds, essential trace elements, and weather conditions, among others. Our comprehensive and unique resource of all associations ( https://helixomics.isglobal.org/ ) will serve to guide future investigation into the biological imprints of the early life exposome.
The growth of galaxies is one of the key problems in understanding the structure and evolution of the universe and its constituents. Galaxies can grow their stellar mass by accretion of halo or ...intergalactic gas clouds, or by merging with smaller or similar mass galaxies. The gas available translates into a rate of star formation, which controls the generation of metals in the universe. The spatially resolved history of their stellar mass assembly has not been obtained so far for any given galaxy beyond the Local Group. Here we demonstrate how massive galaxies grow their stellar mass inside-out. We report the results from the analysis of the first 105 galaxies of the largest three-dimensional spectroscopic survey to date of galaxies in the local universe (CALIFA). We apply the fossil record method of stellar population spectral synthesis to recover the spatially and time resolved star formation history of each galaxy. We show, for the first time, that the signal of downsizing is spatially preserved, with both inner and outer regions growing faster for more massive galaxies. Further, we show that the relative growth rate of the spheroidal component, nucleus, and inner galaxy, which happened 5-7 Gyr ago, shows a maximum at a critical stellar mass ~7 x 10 super(10) M sub(middot in circle). We also find that galaxies less massive than ~10 super(10) M sub(middot in circle) show a transition to outside-in growth, thus connecting with results from resolved studies of the growth of low-mass galaxies.
Summary
Background
X‐linked recessive ichthyosis (XLI) is a relatively common type of ichthyosis caused by a deficiency in the steroid sulfatase (STS) enzyme. It is the only type of ichthyosis that ...can be both syndromic and nonsyndromic. Typical clinical features include dark‐brown scale of variable size favouring the extensor surfaces of the extremities.
Objectives
To characterize clinically nonsyndromic XLI, with a particular focus on extracutaneous manifestations.
Methods
This was a multicentre retrospective review of clinical findings from a case series of patients with a clinical and genetic diagnosis of XLI.
Results
We identified 30 patients with XLI belonging to 25 different families carrying a deletion in the STS locus. All patients had dark scales of variable size on the extensor surfaces of the extremities. Lack of flexural involvement and pruritus were common but inconsistent findings, whereas palmoplantar hyperlinearity was absent in all but one patient. A history of orchiopexy was present in 10% and thus was more common than expected vs. the general population (3%). Neurological disorders including epilepsy (13%) and attention deficit hyperactivity disorder (ADHD; 30%) were over‐represented in patients with XLI.
Conclusions
This was a retrospective study with a limited number of patients. In the absence of confirmatory genetic testing and family history of the disease, dark‐brown scale of the extensor surfaces and the absence of palmoplantar hyperlinearity appear to be the most reliable clinical findings supporting a diagnosis of XLI. Dermatologists should be aware of the high prevalence of ADHD and epilepsy in patients with nonsyndromic XLI.
What's already known about this topic?
Nonsyndromic X‐linked recessive ichthyosis is a relatively common type of ichthyosis.
Prior studies found a high prevalence of cryptorchidism and attention deficit hyperactivity disorder (ADHD).
What does this study add?
We identified a high prevalence of epilepsy (13%), confirmed a high frequency of ADHD (30%) and found a 10% prevalence of orchiopexy.
We also quantified other common findings such palmoplantar hyperlinearity (almost always absent) and pruritus (present in 60% of patients).
Linked Comment: Traupe. Br J Dermatol 2018; 179:821–822.
Plain language summary available online
Respond to this article
PDF
