The shape of SN 1993J re-analysed

SN 1993J is one of the best-studied Type IIb supernovae. Spectropolarimetric data analyses were published over two decades ago at a time when the field of supernova spectropolarimetry was in its infancy. Here, we present a new analysis of the spectropolarimetric data of SN 1993J and an improved estimate of its interstellar polarization (ISP) as well as a critical review of ISP removal techniques employed in the field. The polarization of SN 1993J is found to show significant alignment on the q − u plane, suggesting the presence of a dominant axis and therefore of continuum polarization. We also see strong line polarization features, including H β, He I λ5876, H α, He I λ6678, He I λ7065, and high velocity (HV) components of He I λ5876 and H α. SN 1993J is therefore the second example of a stripped-envelope supernova, alongside iPTF13bvn, with prominent HV helium polarization features, and the first to show a likely HV H α contribution. Overall, we determine that the observed features can be interpreted as the superposition of anisotropically distributed line forming regions over ellipsoidal ejecta. We cannot exclude the possibility of an off-axis energy source within the ejecta. These data demonstrate the rich structures that are inaccessible if solely considering the flux spectra but can be probed by spectropolarimetric observations. In future studies, the new ISP corrected data can be used in conjunction with 3D radiative transfer models to better map the geometry of the ejecta of SN 1993J

Supernova 2014J at M82 – II. Direct analysis of a middle-class Type Ia supernova

We analyze a time series of optical spectra of SN 2014J from almost two weeks prior to maximum to nearly four months after maximum. We perform our analysis using the SYNOW code, which is well suited to track the distribution of the ions with velocity in the ejecta. We show that almost all of the spectral features during the entire epoch can be identified with permitted transitions of the common ions found in normal SNe Ia in agreement with previous studies. We show that 2014J is a relatively normal SN Ia. At early times the spectral features are dominated by Si II, S II, Mg II, and Ca II. These ions persist to maximum light with the appearance of Na I and Mg I. At later times iron-group elements also appear, as expected in the stratified abundance model of the formation of normal type Ia SNe. We do not find significant spectroscopic evidence for oxygen, until 100 days after maximum light. The +100 day identification of oxygen is tentative, and would imply significant mixing of unburned or only slight processed elements down to a velocity of 6,000 km~s−1. Our results are in relatively good agreement with other analyses in the IR. We briefly compare SN 2011fe to SN 2014J and conclude that the differences could be due to different central densities at ignition or differences in the C/O ratio of the progenitors

Analysis of N,N-Dimethylamphetamine in Wastewater - A Pyrolysis Marker and Synthesis Impurity of Methamphetamine

The increased availability of high purity crystalline methamphetamine (MA) in Australia raised concerns because of high dosages and its potential consumption through inhalation. The present work investigates the possibility of using wastewater levels of N,N-dimethylamphetamine (DMA), a pyrolysis by-product formed during smoking, as an indirect indicator of MA smoking. A dedicated liquid chromatography time-of-flight mass spectrometry (LC-QTOF-MS) method was setup to detect and quantify DMA in the wastewater samples. Wastewater samples were collected from eight locations across Australia during the period 2011-2016. Data about the abundance of DMA in MA seizures as well as in residues from drug paraphernalia (i.e., pipes) were obtained from forensic laboratories in Australia. DMA/MA ratios measured in wastewater ranged from 0.0001 to 0.09 (median 0.007). DMA/MA ratios in bulk seizures are generally below 0.0025, with a median value of 0.0004, whilst residues in paraphernalia ranged from 0.031 to 3.37. DMA/MA ratios in wastewater decreased in the investigated period, in parallel to an increase in MA loads. Furthermore, wastewater analyses highlighted a strong positive correlation between DMA/MA ratios and per capita MA use (Pearson's correlation ρ= 0.61, p-value < 0.001). Nonetheless, geographical specificities could be highlighted between the investigated locations. The obtained data could help authorities detect hot spots of drug use as well as to plan specific intervention campaigns to tackle the issue. In future, simultaneous analysis of DMA and MA in both wastewater and seizures could improve our understanding about MA use and its consumption patterns

Examining the Properties of Low-Luminosity Hosts of Type Ia Supernovae from ASAS-SN

We present a spectroscopic analysis of 44 low-luminosity host galaxies of Type Ia supernovae (SNe Ia) detected by the All-Sky Automated Survey for Supernovae (ASAS-SN), using the emission lines to measure metallicities and star formation rates. We find that although the star formation activity of our sample is representative of general galaxies, there is some evidence that the lowest-mass SN Ia host galaxies (log($M_\star/M_\odot$)$<8$) in our sample have high metallicities compared to general galaxies of similar masses. We also identify a subset of 5 galaxies with particularly high metallicities. This highlights the need for spectroscopic analysis of more low-luminosity, low-mass SN Ia host galaxies to test the robustness of these conclusions and their potential impact on our understanding of SN Ia progenitors.Comment: 13 pages, 7 figures, 2 tables. Submitted to ApJ. Full versions of the tables in the paper are available in machine-readable format as ancillary file

Counting stillbirths and COVID 19-there has never been a more urgent time.

International audienceNo abstract availabl

Extracorporeal membrane oxygenation for very high-risk transcatheter aortic valve implantation

Background Transcatheter aortic valve implantation (TAVI) can cause profound haemodynamic perturbation in the peri-operative period. Veno-arterial extracorporeal membrane oxygenation (ECMO) can be used to provide cardiorespiratory support during this time, either prophylactically or emergently

Studying the endothelial glycocalyx in vitro: what is missing?

All human cells are coated by a surface layer of proteoglycans, glycosaminoglycans (GAGs) and plasma proteins, called the glycocalyx. The glycocalyx transmits shear stress to the cytoskeleton of endothelial cells, maintains a selective permeability barrier, and modulates adhesion of blood leukocytes and platelets. Major components of the glycocalyx, including syndecans, heparan sulfate, and hyaluronan, are shed from the endothelial surface layer during conditions including ischaemia and hypoxia, sepsis, atherosclerosis, diabetes, renal disease, and some viral infections. Studying mechanisms of glycocalyx damage in vivo can be challenging due to the complexity of immuno-inflammatory responses which are inextricably involved. Previously, both static as well as perfused in vitro models have studied the glycocalyx, and have reported either imaging data, assessment of barrier function, or interactions of blood components with the endothelial monolayer. To date, no model has simultaneously incorporated all these features at once, however such a model would arguably enhance the study of vasculopathic processes. This review compiles a series of current in vitro models described in the literature that have targeted the glycocalyx layer, their limitations, and potential opportunities for further developments in this field

Are Women Who Work in Bars, Guesthouses and Similar Facilities a Suitable Study Population for Vaginal Microbicide Trials in Africa?

BACKGROUND: A feasibility study was conducted to investigate whether an occupational at-risk cohort of women in Mwanza, Tanzania are a suitable study population for future phase III vaginal microbicide trials. METHODOLOGY/PRINCIPAL FINDINGS: 1573 women aged 16-54 y working in traditional and modern bars, restaurants, hotels, guesthouses or as local food-handlers were enrolled at community-based reproductive health clinics, provided specimens for HIV/STI and pregnancy testing, and asked to attend three-monthly clinical follow-up visits for 12-months. HIV positive and negative women were eligible to enter the feasibility study and to receive free reproductive health services at any time. HIV prevalence at baseline was 26.5% (417/1573). HIV incidence among 1156 sero-negative women attending at baseline was 2.9/100PYs. Among 1020 HIV sero-negative, non-pregnant women, HIV incidence was 2.0/100PYs, HSV-2 incidence 12.7/100PYs and pregnancy rate 17.8/100PYs. Retention at three-months was 76.3% (778/1020). Among 771 HIV sero-negative, non-pregnant women attending at three-months, subsequent follow-up at 6, 9 and 12-months was 83.7%, 79.6%, and 72.1% respectively. Older women, those who had not moved home or changed their place of work in the last year, and women working in traditional bars or as local food handlers had the highest re-attendance. CONCLUSIONS/SIGNIFICANCE: Women working in food outlets and recreational facilities in Tanzania and other parts of Africa may be a suitable study population for microbicide and other HIV prevention trials. Effective locally-appropriate strategies to address high pregnancy rates and early losses to follow-up are essential to minimise risk to clinical trials in these settings

Intravaginal and Menstrual Practices among Women Working in Food and Recreational Facilities in Mwanza, Tanzania: Implications for Microbicide Trials

Intravaginal and menstrual practices may potentially influence results of trials of microbicides for HIV prevention through effects on the vaginal environment and on adherence to microbicide and placebo products. As part of the feasibility study for the Microbicides Development Programme Phase 3 trial of a vaginal microbicide in Mwanza, a variety of quantitative and qualitative methods were used to describe these practices, associations with behaviour and underlying social norms among women working in food and recreational facilities. Intravaginal cleansing by inserting fingers and either water alone or soap and water was thought necessary to remove “uchafu” (dirt), referring to vaginal secretions, including menstrual blood and post-coital discharge. Vaginal cleansing was carried out within 2 hours after 45% of sex acts. Sexual enhancement practices were less common. Intravaginal and menstrual practices and associated behaviours and demographic factors should be measured and monitored throughout microbicide trials to enable analyses of their impacts on microbicide effectiveness