Galaxy formation in the Planck cosmology - III. The high-redshift universe

We present high-redshift predictions of the star formation rate distribution function (SFRDF), UV luminosity function (UVLF), galactic stellar mass function (GSMF), and specific star formation rates (sSFRs) of galaxies from the latest version of the Munich semi-analytic model L-GALAXIES. We find a good fit to both the shape and normalization of the SFRDF at z = 4–7, apart from a slight underprediction at the low-SFR end at z = 4. Likewise, we find a good fit to the faint number counts for the observed UVLF at brighter magnitudes our predictions lie below the observations, increasingly so at higher redshifts. At all redshifts and magnitudes, the raw (unattenuated) number counts for the UVLF lie above the observations. Because of the good agreement with the SFR we interpret our underprediction as an overestimate of the amount of dust in the model for the brightest galaxies, especially at high redshift. While the shape of our GSMF matches that of the observations, we lie between (conflicting) observations at z = 4–5, and underpredict at z = 6–7. The sSFRs of our model galaxies show the observed trend of increasing normalization with redshift, but do not reproduce the observed mass dependence. Overall, we conclude that the latest version of L-GALAXIES, which is tuned to match observations at z ≤ 3, does a fair job of reproducing the observed properties of galaxies at z ≥ 4. More work needs to be done on understanding observational bias at high redshift, and upon the dust model, before strong conclusions can be drawn on how to interpret remaining discrepancies between the model and observations

Potential of wind turbines to elicit seizures under various meteorological conditions

Purpose: To determine the potential risk of epileptic seizures from wind turbine shadow flicker under various meteorologic conditions. Methods: We extend a previous model to include attenuation of sunlight by the atmosphere using the libradtran radiative transfer code. Results: Under conditions in which observers look toward the horizon with their eyes open we find that there is risk when the observer is closer than 1.2 times the total turbine height when on land, and 2.8 times the total turbine height in marine environments, the risk limited by the size of the image of the sun's disc on the retina. When looking at the ground, where the shadow of the blade is cast, observers are at risk only when at a distance <36 times the blade width, the risk limited by image contrast. If the observer views the horizon and closes their eyes, however, the stimulus size and contrast ratio are epileptogenic for solar elevation angles down to approximately 5°. Discussion: Large turbines rotate at a rate below that at which the flicker is likely to present a risk, although there is a risk from smaller turbines that interrupt sunlight more than three times per second. For the scenarios considered, we find the risk is negligible at a distance more than about nine times the maximum height reached by the turbine blade, a distance similar to that in guidance from the United Kingdom planning authorities. © 2009 International League Against Epilepsy

Introduction:navigating secrecy in security research

This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book offers a rich set of analyses of the challenges of secrecy in security research, and sets out practical ways to navigate, encircle and work with secrecy. It aims to offer not just a conceptual reflection on the dynamics of secrecy, but also practical, hands-on methodological guidance for qualitative fieldwork in the security domain. The book describes new ways of conceptualising secrecy in relation to fieldwork, by understanding secrecy as more than a barrier to be overcome. It shows how secrecy itself can be made productive to the analysis: mapping secrecies and sensitivities in the field can itself be revealing; navigating obfuscation is co-productive of research design and data. The book focuses on reconceptualising secrecy as a complex practice and mode of power

Susceptibility to pattern glare following stroke

The aim of this work was to measure susceptibility to pattern glare within a stroke group, employing a direct method of assessment. Twenty stroke subjects, aged 38-85 years, were recruited, along with an age-matched control group (n = 20). Assessment of pattern glare susceptibility was undertaken using the pattern glare test. An abnormal degree of pattern glare is present when individuals score >1 on the mid-high spatial frequency difference variable, a relative score that allows for normalization of the subject, or >3 when viewing the mid spatial frequency grating. Stroke subjects demonstrate elevated levels of pattern glare compared to normative data values and a control population, as determined using the pattern glare test. This was most notable when considering the output measure for the mid-high difference variable. The mean score for the mid-high difference variable was 2.15 SD 1.27 for the stroke subjects versus 0.10 SD 1.12 for the control subjects. When considering the mid-high difference variable, 75% of the stroke group recorded an abnormal level of pattern glare compared to 5% in the control group. This study demonstrates an association between stroke subjects and elevated levels of pattern glare. Cortical hyperexcitability has been shown to present following stroke, and this has been proposed as a plausible explanation for the perceptual distortions experienced by individuals susceptible to pattern glare. Further work to assess the benefits of spectral filters in reducing perceptual distortions in stroke patients is currently underway

1H0707-495 in 2011: An X-ray source within a gravitational radius of the event horizon

The Narrow Line Seyfert 1 Galaxy 1H0707-495 went in to a low state from 2010 December to 2011 February, discovered by a monitoring campaign using the X-Ray Telescope on the Swift satellite. We triggered a 100 ks XMM-Newton observation of the source in 2011 January, revealing the source to have dropped by a factor of ten in the soft band, below 1 keV, and a factor of 2 at 5 keV, compared with a long observation in 2008. The sharp spectral drop in the source usually seen around 7 keV now extends to lower energies, below 6 keV in our frame. The 2011 spectrum is well fit by a relativistically-blurred reflection spectrum similar to that which fits the 2008 data, except that the emission is now concentrated solely to the central part of the accretion disc. The irradiating source must lie within 1 gravitational radius of the event horizon of the black hole, which spins rapidly. Alternative models are briefly considered but none has any simple physical interpretation.Comment: 9 pages, 19 figures, MNRAS in pres

Evaluation of the Conrad N. Hilton Foundation Chronic Homelessness Initiative: 2016 Evaluation Report, Phase I

In 2011, the Conrad N. Hilton Foundation partnered with Abt Associates Inc. to conduct an evaluation of the Hilton Foundation's Chronic Homelessness Initiative, with the goal of answering the overarching question: Is the Chronic Homelessness Initiative an effective strategy to end and prevent chronic homelessness in Los Angeles County? This final evaluation report provides an overview of the community's progress on selected metrics over five years, January 2011 through December 2015.Although the community, with support from the Foundation, has made substantial progress in furthering support for permanent supportive housing (PSH) as a solution to chronic homelessness, significant challenges remain. In the January 2016 point-in-time count, 14,058 individuals were reported as experiencing chronic homelessness within LA County. This represents an increase of nearly 5,000 from the point-in-time count conducted in January 2011 at the start of the Initiative, despite the high number of housing placements during this same time period. Economic conditions, insufficient and shrinking availability of affordable housing, and unmet need for mental health and supportive services are credited not only with cancelling out the effect of the housing placements but also with adding to the count within the collaborative system.We do not believe that these challenges and the increasing numbers of chronically homeless people suggest that the community's strategy on chronic homelessness is failing. Rather, the growth in numbers suggests that the new systems that coalesced through the work of Phase I of the Initiative are needed more than ever as of the end of 2015. Many stakeholders consider LA to be at a possible turning point, with significant new commitments of funding to address chronic homelessness and more alignment on the issue among elected officials and leaders of the key local government agencies.There is no question that the landscape shifted between 2011 and 2015 and that the community reached a new standard for collaboration as of January 2016. Strong systems were in place, and public agencies had embraced new responsibilities. As the Foundation looks ahead to the next phase of the Initiative, the challenges of getting to the scale needed to end chronic homelessness will require all to take stock of their roles and assess their best fit within the collaborative system

Percutaneous Transaxillary versus Surgically- Assisted Transsubclavian TAVR: A Single Center Experience

Background: Transfemoral access is the standard approach for transcatheter aortic valve replacement (TAVR). However, an important proportion of TAVR patients may not be considered for transfemoral access because of anatomic reasons - for these patients, an alternative access route must be considered. The objective of this study was to assess the safety and efficacy of percutaneous transaxillary TAVR as compared to surgically assisted transsubclavian TAVR and to report the feasibility of next-day discharge following this percutaneous approach. Methods: Since January 2019, all transaxillary TAVR at our institution were performed using a standardized percutaneous approach - this was compared to our prior experience with transsubclavian TAVR via surgical cut down. Results: Sixty-four patients underwent transsubclavian/axillary TAVR since 2014: 40 surgically assisted transsubclavian (2014-2018) and 24 fully percutaneous transaxillary TAVR (2019-2020). Both groups had similar baseline characteristics. In the surgically assisted TAVR group, six major vascular complications were encountered and six patients were rehospitalized within 30 days after TAVR vs. no patients with a major vascular complication and one patient rehospitalized within 30 days in the percutaneous transaxillary group. Hospitalization was significantly shorter for patients treated by percutaneous vs. surgical approach (1.2 vs. 4.4 days; p &lt; 0.001). Twenty out of 24 percutaneous transaxillary TAVR patients (83%) were discharged the day after TAVR. Conclusion: Percutaneous transaxillary TAVR is a safe and effective treatment option for patients not suitable for transfemoral TAVR. Significant reduction in hospital length-of-stay was noted in percutaneous transaxillary vs. surgically assisted transsubclavian TAVR