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Background While bed nets and insecticide spraying have had significant impact on malaria burden in many endemic regions, outdoor vector feeding and insecticide resistance may ultimately limit their contribution to elimination and control campaigns. Complementary vector control methods such as endectocides or systemic insecticides, where humans or animals are treated with drugs that kill mosquitoes upon ingestion via blood meal, are therefore generating much interest. This work explores the conditions under which long-lasting systemic insecticides would have a substantial impact on transmission and burden. Methods Hypothetical long-lasting systemic insecticides with effective durations ranging from 14 to 90 days are simulated using an individual-based mathematical model of malaria transmission. The impact of systemic insecticides when used to complement existing vector control and drug campaigns is evaluated in three settings—a highly seasonal high-transmission setting, a near-elimination setting with seasonal travel to a high-risk area, and a near-elimination setting in southern Africa. Results At 60% coverage, a single round of long-lasting systemic insecticide with effective duration of at least 60 days, distributed at the start of the season alongside a seasonal malaria chemoprevention campaign in a high-transmission setting, results in further burden reduction of 30–90% depending on the sub-populations targeted. In a near-elimination setting where transmission is sustained by seasonal travel to a high-risk area, targeting high-risk travellers with systemic insecticide with effective duration of at least 30 days can result in likely elimination even if intervention coverage is as low as 50%. In near-elimination settings with robust vector control, the addition of a 14-day systemic insecticide alongside an anti-malarial in mass drug administration (MDA) campaigns can decrease the necessary MDA coverage from about 85% to the more easily achievable 65%. Conclusions While further research into the safety profile of systemic insecticides is necessary before deployment, models predict that long-lasting systemic insecticides can play a critical role in reducing burden or eliminating malaria in a range of contexts with different target populations, existing malaria control methods, and transmission intensities. Continued investment in lengthening the duration of systemic insecticides and improving their safety profile is needed for this intervention to achieve its fullest potential.

In this study we explore the complex multi-phase gas of the circumgalactic medium (CGM) surrounding galaxies. We propose and implement a novel, super-Lagrangian 'CGM zoom' scheme in the moving-mesh code AREPO, which focuses more resolution into the CGM and intentionally lowers resolution in the dense ISM. We run two cosmological simulations of the same galaxy halo, once with a simple 'no feedback' model, and separately with a more comprehensive physical model including galactic-scale outflows as in the Illustris simulation. Our chosen halo has a total mass of ~10^12 Msun at z ~ 2, and we achieve a median gas mass (spatial) resolution of ~2,200 solar masses (~95 parsecs) in the CGM, six-hundred (fourteen) times better than in the Illustris-1 simulation, a higher spatial resolution than any cosmological simulation at this mass scale to date. We explore the primary channel(s) of cold-phase CGM gas production in this regime. We find that winds substantially enhance the amount of cold gas in the halo, also evidenced in the covering fractions of HI and the equivalent widths of MgII out to large radii, in better agreement with observations than the case without galactic winds. Using a tracer particle analysis to follow the thermodynamic history of gas, we demonstrate how the majority of this cold, dense gas arises due to rapid cooling of the wind material interacting with the hot halo, and how large amounts of cold, ~10^4 K gas can be produced and persist in galactic halos with Tvir ~ 10^6 K. At the resolutions presently considered, the quantitative properties of the CGM we explore are not appreciably affected by the refinement scheme., MNRAS submitted, comments welcome. High-res version at http://www.mpa-garching.mpg.de/~dnelson/papers/Suresh19_zooming2.pdf

We analyze the mass, temperature, metal enrichment, and OVI abundance of the circumgalactic medium (CGM) around $z\sim 0.2$ galaxies of mass $10^9 M_\odot, Comment: Submitted to MNRAS. 18 pages, 16 figures

We compare simulations, including the Illustris simulations, to observations of CIV and CII absorption at z=2-4. These are the CIV column density distribution function in the column density range $10^{12} - 10^{15}$ cm$^{-2}$, the CIV equivalent width distribution at 0.1 - 2 \AA, and the covering fractions and equivalent widths of CIV 1548 and CII 1337 around DLAs. In the context of the feedback models we investigate, all CIV observations favour the use of more energetic wind models, which are better able to enrich the gas surrounding halos. We propose two ways to achieve this; an increased wind velocity and an increase in wind thermal energy. However, even our most energetic wind models do not produce enough absorbers with CIV equivalent width > 0.6 \AA, which in our simulations are associated with the most massive haloes. All simulations are in reasonable agreement with the CII covering fraction and equivalent widths around Damped Lyman-$\alpha$ absorbers, although there is a moderate deficit in one bin 10 - 100 kpc from the DLA. Finally, we show that the CIV in our simulations is predominantly photoionized., Comment: 18 pages, 15 figures, published in MNRAS. Results tables added

We investigate the variation of the ratio of the equivalent widths of the FeII$\lambda$2600 line to the MgII$\lambda\lambda$2796,2803 doublet as a function of redshift in a large sample of absorption lines drawn from the JHU-SDSS Absorption Line Catalog. We find that despite large scatter, the observed ratio shows a trend where the equivalent width ratio $\mathcal{R}\equiv W_{\rm FeII}/W_{\rm MgII}$ decreases monotonically with increasing redshift $z$ over the range $0.55 \le z \le 1.90$. Selecting the subset of absorbers where the signal-to-noise ratio of the MgII equivalent width $W_{\rm MgII}$ is $\ge$3 and modeling the equivalent width ratio distribution as a gaussian, we find that the mean of the gaussian distribution varies as $\mathcal{R}\propto (-0.045\pm0.005)z$. We discuss various possible reasons for the trend. A monotonic trend in the Fe/Mg abundance ratio is predicted by a simple model where the abundances of Mg and Fe in the absorbing clouds are assumed to be the result of supernova ejecta and where the cosmic evolution in the SNIa and core-collapse supernova rates is related to the cosmic star-formation rate. If the trend in $\mathcal{R}$ reflects the evolution in the abundances, then it is consistent with the predictions of the simple model., Comment: 10 pages, 4 figures, final version published in MNRAS

Background Female gender and hypothyroidism are considered independent risk factors for mortality following CABG. The dysfunctional thyroid gland has profound impact on the cardiovascular system.