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We present Ly alpha imaging of 45 low-redshift star-forming galaxies observed with the Hubble Space Telescope. The galaxies have been selected to have moderate to high star formation rates (SFRs) using far-ultraviolet (FUV) luminosity and H alpha equivalent width criteria, but no constraints on Ly alpha luminosity. We employ a pixel stellar continuum fitting code to obtain accurate continuum-subtracted Ly alpha, H alpha, and H beta maps. We find that Ly alpha is less concentrated than FUV and optical line emission in almost all galaxies with significant Ly alpha emission. We present global measurements of Ly alpha and other quantities measured in apertures designed to capture all of the Ly alpha emission. We then show how the escape fraction of Ly alpha relates to a number of other measured quantities (mass, metallicity, star formation, ionization parameter, and extinction). We find that the escape fraction is strongly anticorrelated with nebular and stellar extinction, weakly anticorrelated with stellar mass, but no conclusive evidence for correlations with other quantities. We show that Ly alpha escape fractions are inconsistent with common dust extinction laws, and discuss how a combination of radiative transfer effects and clumpy dust models can help resolve the discrepancies. We present an SFR calibration based on Ly alpha luminosity, where the equivalent width of Ly alpha is used to correct for nonunity escape fraction, and show that this relation provides a reasonably accurate SFR estimate. We also show stacked growth curves of Ly alpha for the galaxies that can be used to find aperture loss fractions at a given physical radius.

As memory capacity has outstripped TLB coverage, large data applications suffer from frequent page table walks. We investigate two complementary techniques for addressing this cost: reducing the number of accesses required and reducing the latency of each access. The first approach is accomplished by opportunistically "flattening" the page table: merging two levels of traditional 4 KB page table nodes into a single 2 MB node, thereby reducing the table's depth and the number of indirections required to traverse it. The second is accomplished by biasing the cache replacement algorithm to keep page table entries during periods of high TLB miss rates, as these periods also see high data miss rates and are therefore more likely to benefit from having the smaller page table in the cache than to suffer from increased data cache misses. We evaluate these approaches for both native and virtualized systems and across a range of realistic memory fragmentation scenarios, describe the limited changes needed in our kernel implementation and hardware design, identify and address challenges related to self-referencing page tables and kernel memory allocation, and compare results across server and mobile systems using both academic and industrial simulators for robustness. We find that flattening does reduce the number of accesses required on a page walk (to 1.0), but its performance impact (+2.3%) is small due to Page Walker Caches (already 1.5 accesses). Prioritizing caching has a larger effect (+6.8%), and the combination improves performance by +9.2%. Flattening is more effective on virtualized systems (4.4 to 2.8 accesses, +7.1% performance), due to 2D page walks. By combining the two techniques we demonstrate a state-of-the-art +14.0% performance gain and -8.7% dynamic cache energy and -4.7% dynamic DRAM energy for virtualized execution with very simple hardware and software changes.

In less than 15 years, child baptism has gone from being a mainstream tradition to a minority practice. This decline is a result of both high unaffiliation, especially with the Church of Sweden, and a more diversified religious society due to migration. Using microdata from parents of children born in 2005 and 2015, we were able to discern that differences in the practice of child baptism in the Church of Sweden are positively associated with the parents' relation to the church, residence in rural areas, and income. Our LPM analysis shows that the probability of a child being baptized are mainly determined by the parents' relation to the church when controlling for all the other variables. The most influential factors are the mother's affiliation and an urban lifestyle. Parents' marital status and socioeconomic circumstances have a strong effect on the decision to baptize a child, therefore affecting who becomes a future member of the church.

Bakgrund och problem: Svenska banker har de senaste åren utökat hållbarhetsarbetet mendet finns fortfarande många områden där kraven inte uppfylls, däribland miljöområdet.Växthusgasutsläpp till följd av svenskars sparande på världens börser motsvarar utsläppenfrån deras konsumtion, boende och resor. Finansiella företag är vana att hantera risker, men i och med klimatförändringarna tillkommer nya utmaningar. Banker spelar en viktig roll för att motverka klimatförändringarna, men idag är transparensen bristande vilket gör det svårt för kunder att ta klimatsmarta beslut. ● I vilket syfte arbetar banker för att minska sin klimatpåverkan? ● Hur arbetar banker för att minska klimatrelaterade risker? ● Hur kan ökad transparens påverka bankers klimatpåverkan? Syftet med studien är att beskriva varför banker arbetar med klimatrelaterade frågor,hur de förhåller sig till klimatrelaterade risker samt hur ökad transparens mot intressenter påverkar omfattningen av bankers klimatarbete. Studien bygger främst på kvalitativ insamling av data. Studien har sin utgångspunkt i en deduktiv ansats med inslag av en induktiv ansats. Intervjuer har genomförts med fem banker, Svenska Bankföreningen, Finansinspektionen och Swedwatch för att erhålla olika perspektiv på problemområdet. Bankerna arbetar för att minska sin klimatpåverkan för att stärka sina varumärken, reducera ryktes- och klimatrelaterade risker samt för att skapa förutsättningar för långsiktig lönsamhet. De klimatrelaterade riskerna hanteras i kreditgivningen och i bedömningen avinvesteringar. Ökad transparens kan påverka bankernas klimatpåverkan genom att välinformerade kunder kan ta mer klimatsmarta beslut samt att ökad transparens driver på konkurrensen mellan bankerna vilket i sin tur driver på dem att minska deras klimatpåverkan.

Simulation is an important part of the evaluation of next-generation computing systems. Detailed, cycle-accurate simulation, however, can be very slow when evaluating realistic workloads on modern microarchitectures. Sampled simulation (e.g., SMARTS and SimPoint) improves simulation performance by an order of magnitude or more through the reduction of large workloads into a small but representative sample. Additionally, the execution state just prior to a simulation sample can be stored into checkpoints, allowing for fast restoration and evaluation. Unfortunately, changes in software, architecture or fundamental pieces of the microarchitecture (e.g., hardware-software co-design) require checkpoint regeneration. The end result for co-design degenerates to creating checkpoints for each modification, a task checkpointing was designed to eliminate. Therefore, a solution is needed that allows for fast and accurate simulation, without the need for checkpoints. Virtualized fast-forwarding (VFF), an alternative to using checkpoints, allows for execution at near-native speed between simulation points. Warming the micro-architectural state prior to each simulation point, however, requires functional simulation, a costly operation for large caches (e.g., 8 M B). Simulating future systems with caches of many MBs can require warming of billions of instructions, dominating simulation time. This paper proposes CoolSim, an efficient simulation framework that eliminates cache warming. CoolSim uses VFF to advance between simulation points collecting at the same time sparse memory reuse information (MRI). The MRI is collected more than an order of magnitude faster than functional simulation. At the simulation point, detailed simulation with a statistical cache model is used to evaluate the design. The previously acquired MRI is used to estimate whether each memory request hits in the cache. The MRI is an architecturally independent metric and a single profile can be used in simulation

Sampling (e.g., SMARTS and SimPoint) improves simulation performance by an order of magnitude or more through the reduction of large workloads into a small but representative sample. Virtualized fast-forwarding (e.g., FSA) speeds up simulation further by advancing execution at near-native speed between simulation points, making cache warming the critical limiting factor for simulation performance. CoolSim is an efficient simulation framework that eliminates cache warming. It collects sparse memory reuse information (MRI) while advancing between simulation points using virtualized fast-forwarding. During detailed simulation, a statistical cache model uses the previously acquired MRI to estimate the performance of the caches. CoolSim builds upon KVM and gem5 and runs 19x faster than the state-of-the-art sampled simulation. It estimates the CPI of the SPEC CPU2006 bench-marks with 3.62% error on average, across a wide range of cache sizes.

Context: Recent numerical simulations suggest that the strength of the Lyman alpha (Ly alpha) line of star-forming disk galaxies strongly depends on the inclination at which they are observed: from edge-on to face-on, we expect to see a change from a strongly attenuated Ly alpha line to a strong Ly alpha emission line. Aims: We aim to understand how a strong Ly alpha emission line is able to escape from the low-redshift highly inclined (edge-on) disk galaxy Mrk 1486 (z similar to 0.0338). To our knowledge, this work is the first observational study of Ly alpha transport inside an edge-on disk galaxy. Methods: Using a large set of HST imaging and spectroscopic data, we investigated the interstellar medium (ISM) structure and the dominant source of Ly alpha radiation inside Mrk 1486. Moreover, using a 3D Monte Carlo Ly alpha radiation transfer code, we studied the radiative transfer of Ly alpha and UV continuum photons inside a 3D geometry of neutral hydrogen (HI) and dust that models the ISM structure at the galaxy center. Our numerical simulations predicted the Ly alpha line profile that we then compared to the one observed in the HST/COS spectrum of Mrk 1486. Results: While a pronounced Ly alpha absorption line emerges from the disk of Mrk 1486, very extended Ly alpha structures are observed at large radii from the galaxy center: a large Ly alpha-halo and two very bright Ly alpha regions located slightly above and below the disk plane. The analysis of IFU H alpha spectroscopic data of Mrk 1486 indicates the presence of two bipolar outflowing halos of HI gas at the same location as these two bright Ly alpha regions. Comparing different diagnostic diagrams (such as [OIII](5007)/H beta versus [OI](6300)/H alpha) to photo-and shock-ionization models, we find that the Ly alpha production of Mrk 1486 is dominated by photoionization inside the galaxy disk. From this perspective, our numerical simulations succeed in reproducing the strength and shape of the observed Ly alp

Simulation is an important part of the evaluation of next-generation computing systems. Detailed, cycle-level simulation, however, can be very slow when evaluating realistic workloads on modern microarchitectures. Sampled simulation (e.g., SMARTS and SimPoint) improves simulation performance by an order of magnitude or more through the reduction of large workloads into a small but representative sample. Additionally, the execution state just prior to a simulation sample can be stored into checkpoints, allowing for fast restoration and evaluation. Unfortunately, changes in software, architecture or fundamental pieces of the microarchitecture (e.g., hardware-software co-design) require checkpoint regeneration. The end result for co-design degenerates to creating checkpoints for each modification, a task checkpointing was designed to eliminate. Therefore, a solution is needed that allows for fast and accurate simulation, without the need for checkpoints. Virtualized fast-forwarding proposals, like FSA, are an alternative to checkpoints that speed up sampled simulation by advancing the execution at near-native speed between simulation points. They rely, however, on functional simulation to warm the architectural state prior to each simulation point, a costly operation for moderately-sized last-level caches (e.g., above 8MB). Simulating future systems with DRAM caches of many GBs can require warming of billions of instructions, dominating the time for simulation and negating the benefit of virtualized fast-forwarding. This paper proposes CoolSim, an efficient simulation framework that eliminates cache warming. CoolSim advances between simulation points using virtualized fast-forwarding, while collecting sparse memory reuse information (MRI). The MRI is collected more than an order of magnitude faster than functional warming. At the simulation point, detailed simulation is used to evaluate the design while a statistical cache model uses the previously acquired MRI to esti

We present high-resolution far-UV spectroscopy of the 14 galaxies of the Lyα Reference Sample; a sample of strongly star-forming galaxies at low redshifts (0.028 < z < 0.18). We compare the derived properties to global properties derived from multi-band imaging and 21 cm H i interferometry and single-dish observations, as well as archival optical SDSS spectra. Besides the Lyα line, the spectra contain a number of metal absorption features allowing us to probe the kinematics of the neutral ISM and evaluate the optical depth and and covering fraction of the neutral medium as a function of line of sight velocity. Furthermore, we show how this, in combination with the precise determination of systemic velocity and good Lyα spectra, can be used to distinguish a model in which separate clumps together fully cover the background source, from the "picket fence" model named by Heckman et al. We find that no one single effect dominates in governing Lyα radiative transfer and escape. Lyα escape in our sample coincides with a maximum velocity-binned covering fraction of 0.9 and bulk outflow velocities of 50 km s−1, although a number of galaxies show these characteristics and yet little or no Lyα escape. We find that Lyα peak velocities, where available, are not consistent with a strong backscattered component, but rather with a simpler model of an intrinsic emission line overlaid by a blueshifted absorption profile from the outflowing wind. Finally, we find a strong anticorrelation between Hα equivalent width and maximum velocity-binned covering factor, and propose a heuristic explanatory model., The Lyman Alpha Reference Sample

Cycle-level microarchitectural simulation is the defacto standard to estimate performance of next-generation platforms. Unfortunately, the level of detail needed for accurate simulation requires complex, and therefore slow, simulation models that run at speeds that are thousands of times slower than native execution. With the introduction of sampled simulation, it has become possible to simulate only the key, representative portions of a workload in a reasonable amount of time and reliably estimate its overall performance. These sampling methodologies provide the ability to identify regions for detailed execution, and through microarchitectural state checkpointing, one can quickly and easily determine the performance characteristics of a workload for a variety of microarchitectural changes. While this strategy of sampling simulations to generate checkpoints performs well for static applications, more complex scenarios involving hardware-software co-design (such as co-optimizing both a Java virtual machine and the microarchitecture it is running on) cause this methodology to break down, as new microarchitectural checkpoints are needed for each memory hierarchy configuration and software version. Solutions are therefore needed to enable fast and accurate simulation that also address the needs of hardware-software co-design and exploration. In this work we present a methodology to enhance checkpoint-based sampled simulation. Our solution integrates hardware virtualization to provide near-native speed, virtualized fast-forwarding to regions of interest, and parallel detailed simulation. However, as we cannot warm the simulated caches during virtualized fast-forwarding, we develop a novel approach to estimate the error introduced by limited cache warming, through the use of optimistic and pessimistic warming simulations. Using virtualized fast-forwarding (which operates at 90% of native speed on average), we demonstrate a parallel sampling simulator that can be used to a, UPMARC, CoDeR-MP

We present ultraviolet (UV) observations of six nearby Type Ia supernovae (SNe Ia) obtained with the Hubble Space Telescope, three of which were also observed in the near-IR (NIR) with Wide-Field Camera 3. UV observations with the Swift satellite, as well as ground-based optical and NIR data provide complementary information. The combined data set covers the wavelength range 0.2-2 mu m. By also including archival data of SN 2014J, we analyse a sample spanning observed colour excesses up to E(B - V) = 1.4 mag. We study the wavelength-dependent extinction of each individual SN and find a diversity of reddening laws when characterized by the total-to-selective extinction R-V. In particular, we note that for the two SNe with E(B - V) greater than or similar to 1 mag, for which the colour excess is dominated by dust extinction, we find R-V = 1.4 +/- 0.1 and R-V = 2.8 +/- 0.1. Adding UV photometry reduces the uncertainty of fitted R-V by similar to 50 per cent allowing us to also measure R-V of individual low-extinction objects which point to a similar diversity, currently not accounted for in the analyses when SNe Ia are used for studying the expansion history of the Universe.

Context. The transport of Ly alpha photons in galaxies is a complex process and the conditions under which Ly alpha photons manage to escape from certain galaxies is still under investigation. The Lyman alpha reference sample (LARS) is a sample of 14 local star-forming galaxies, designed to study Ly alpha in detail and relate it to rest-frame UV and optical emission. Aims. With the aim of identifying rest-frame UV and optical properties, which are typical of Ly alpha emitters (LAEs, galaxies with EW(Ly alpha) > 20 angstrom) at both low and high redshift, we investigated the morphological properties of the LARS galaxies, in particular the ones that exhibit intense Ly alpha radiation. Methods. We measured sizes and morphological parameters in the continuum, Ly alpha, and Ha images. We studied morphology by using the Gini coefficient vs. M20 and asymmetry vs. concentration diagrams. We then simulated LARS galaxies at z similar to 2 and 5.7, performing the same morphological measurements. We also investigated the detectability of LARS galaxies in current deep field observations. The subsample of LAEs within LARS (LARS-LAEs) was stacked to provide a comparison to stacking studies performed at high redshift. Results. LARS galaxies have continuum size, stellar mass, and rest-frame absolute magnitude typical of Lyman break analogues in the local Universe and also similar to 2 < z < 3 star-forming galaxies and massive LAEs. LARS optical morphology is consistent with the one of merging systems, and irregular or starburst galaxies. For the first time we quantify the morphology in Ly alpha images: even if a variety of intrinsic conditions of the interstellar medium can favour the escape of Ly alpha photons, LARS-LAEs appear small in the continuum, and their Ly alpha is compact. LARS galaxies tend to be more extended in Ly alpha than in the rest-frame UV. It means that Ly alpha photons escape by forming haloes around HII regions of LARS galaxies. Conclusions. The stack

Context: Lyman alpha (Ly alpha) emitting galaxies (LAEs) are used to probe the distant universe and are therefore important for galaxy evolution studies and for providing clues to the nature of the epoch of reionization. However, the exact circumstances under which Lya escapes a galaxy are still not fully understood. Aims. The Trident project is designed to simultaneously examine Ly alpha, H alpha, and Lyman continuum emission from galaxies at redshift z similar to 2, thus linking these three aspects of ionizing radiation in galaxies. In this paper, we outline the strategy of this project and examine the properties of LAEs in the GOODS North field. Methods: We performed a narrowband LAE survey in GOODS North using existing filters and two custom made filters at the Nordic Optical Telescope with MOSCA. We use complementary broadband archival data in the field to make a careful candidate selection and perform optical to near-IR SED fitting. We also estimate far-IR luminosities by matching our candidates to detections in Spitzer/MIPS 24 mu m and Herschel/PACS catalogues. Results. We find a total of 25 LAE candidates, probing mainly the bright end of the LAE luminosity function with L-Ly alpha similar to 1-15 x 10(42) erg s(-1). They display a range of masses of similar to 0.5-50x10(9) M-circle dot, and average ages from a few tens of Myr to 1 Gyr when assuming a constant star formation history. The majority of our candidates also show signs of recent elevated star formation. Three candidates have counterparts in the GOODS-Herschel far-IR catalogue, with luminosities consistent with ultra-luminous infrared galaxies (ULIRGs). Conclusions: The wide range of parameters derived from our SED fitting, as well as part of our sample being detected as ULIRGs, seems to indicate that at these Ly alpha luminosities, LAEs do not necessarily have to be young dwarfs, and that a lack of dust is not required for Ly alpha to escape.