Combining Size and Shape in Weak Lensing

Weak lensing alters the size of images with a similar magnitude to the distortion due to shear. Galaxy size probes the convergence field, and shape the shear field, both of which contain cosmological information. We show the gains expected in the Dark Energy Figure of Merit if galaxy size information is used in combination with galaxy shape. In any normal analysis of cosmic shear, galaxy sizes are also studied, so this is extra statistical information comes for free and is currently unused. There are two main results in this letter: firstly, we show that size measurement can be made uncorrelated with ellipticity measurement, thus allowing the full statistical gain from the combination, provided that $\sqrt{Area}$ is used as a size indicator; secondly, as a proof of concept, we show that when the relevant modes are noise-dominated, as is the norm for lensing surveys, the gains are substantial, with improvements of about 68% in the Figure of Merit expected when systematic errors are ignored. An approximate treatment of such systematics such as intrinsic alignments and size-magnitude correlations respectively suggests that a much better improvement in the Dark Energy Figure of Merit of even a factor of ~4 may be achieved.Comment: Updated to MNRAS published version and added footnot

Senior Recital: Alan Jaffe, viola

Kennesaw State University School of Music presents Senior Recital: Alan Jaffe, viola.https://digitalcommons.kennesaw.edu/musicprograms/1867/thumbnail.jp

Hierarchical Cosmic Shear Power Spectrum Inference

We develop a Bayesian hierarchical modelling approach for cosmic shear power spectrum inference, jointly sampling from the posterior distribution of the cosmic shear field and its (tomographic) power spectra. Inference of the shear power spectrum is a powerful intermediate product for a cosmic shear analysis, since it requires very few model assumptions and can be used to perform inference on a wide range of cosmological models \emph{a posteriori} without loss of information. We show that joint posterior for the shear map and power spectrum can be sampled effectively by Gibbs sampling, iteratively drawing samples from the map and power spectrum, each conditional on the other. This approach neatly circumvents difficulties associated with complicated survey geometry and masks that plague frequentist power spectrum estimators, since the power spectrum inference provides prior information about the field in masked regions at every sampling step. We demonstrate this approach for inference of tomographic shear $E$-mode, $B$-mode and $EB$-cross power spectra from a simulated galaxy shear catalogue with a number of important features; galaxies distributed on the sky and in redshift with photometric redshift uncertainties, realistic random ellipticity noise for every galaxy and a complicated survey mask. The obtained posterior distributions for the tomographic power spectrum coefficients recover the underlying simulated power spectra for both $E$- and $B$-modes.Comment: 16 pages, 8 figures, accepted by MNRA

Weak Lensing with Sizes, Magnitudes and Shapes

Weak lensing can be observed through a number of effects on the images of distant galaxies; their shapes are sheared, their sizes and fluxes (magnitudes) are magnified and their positions on the sky are modified by the lensing field. Galaxy shapes probe the shear field whilst size, magnitude and number density probe the convergence field. Both contain cosmological information. In this paper we are concerned with the magnification of the size and magnitude of individual galaxies as a probe of cosmic convergence. We develop a Bayesian approach for inferring the convergence field from a measured size, magnitude and redshift and demonstrate that the inference on convergence requires detailed knowledge of the joint distribution of intrinsic sizes and magnitudes. We build a simple parameterised model for the size-magnitude distribution and estimate this distribution for CFHTLenS galaxies. In light of the measured distribution, we show that the typical dispersion on convergence estimation is ~0.8, compared to ~0.38 for shear. We discuss the possibility of physical systematics for magnification (similar to intrinsic alignments for shear) and compute the expected gains in the Dark Energy Figure-of-Merit (FoM) from combining magnification with shear for different scenarios regarding systematics: when accounting for intrinsic alignments but no systematics on the magnification signal, including magnification could improve the FoM by upto a factor of ~2.5, whilst when accounting for physical systematics in both shear and magnification we anticipate a gain between ~25% and ~65%. In addition to the statistical gains, the fact that cosmic shear and magnification are subject to different systematics makes magnification an attractive complement to any cosmic shear analysis.Comment: 15 pages, 5 figures, accepted by MNRA

Iliac Compression Syndrome Treated with Stent Placement.

Iliac compression syndrome is usually diagnosed during the third and fourth decades of life when the patient has iliofemoral deep vein thrombosis. Catheter-directed thrombolytic therapy is an accepted method of treatment for iliofemoral deep vein thrombosis, which has been reported to afford greater success with clot dissolution than with system therapy. Although this method is not new, this is the first case, to our knowledge, reporting successful treatment of computerized tomographically demonstrated iliac compression syndrome with stent placement after lysis and insufficient response to balloon angioplasty

Infective endocarditis, 1983–1988: Echocardiographic findings and factors influencing morbidity and mortality

The echocardiograms and clinical records of 70 patients with infective endocarditis seen between 1983 and 1988 were examined to evaluate the role of two-dimensional and Doppler echocardiography in the diagnosis of infective endocarditis and identify risk factors for morbidity and mortality. A blinded observer reviewed the echocardiograms for the presence and size of vegetations and the severity of the valvular regurgitation. Vegetations were identified in 54 (78%) of 69 technically satisfactory echocardiograms. In 38 patients whose heart was examined at surgery or autopsy, all vegetations diagnosed by echocardiography were confirmed, but six additional vegetations were found.Abnormal (≥2+) valvular regurgitation was present in 88% of patients. No patient with ≤1+ regurgitation (n = 8) died or required valve surgery for heart failure, but three of the eight patients did undergo surgery for mycotic aneurysm, recurrent embolism or paravalvular abscess. In patients without embolism before echocardiography, there was a trend toward a greater incidence of subsequent embolism in those with vegetations >10 mm in size (26% [8 of 31] compared with 11% [2 of 18] with vegetations ≤10 mm) (p = 0.19). By multivariate analysis, risk factors for in-hospital death (n = 7) were an infected prosthetic valve (p < 0.007), systemic embolism (p < 0.02) and infection with Staphylococcus aureus(p = 0.05).It is concluded that 1) if valvular regurgitation is ≤1+, the risk of in-hospital death is low, and progression to cardiac surgery for hemodynamic instability is unlikely; 2) there is a trend toward a higher risk of embolization in patients with vegetations >10 mm in size; 3) early mortality now relates to infected prosthetic heart valves, embolism and Staphylococcus aureus; and 4) when a paravalvular abscess or prosthetic valve endocarditis is suspected, transthoracic echocardiographic findings are often equivocal and transesophageal echocardiography may be of benefit

Millennials, Equity, and the Rule of Law: 2014 National Lawyers Convention, \u3ci\u3eHow First Amendment Procedures Protect First Amendment Substance\u3c/i\u3e

A panel, at the National Lawyers Convention, discussed procedure as it relates to First Amendment rights. The panel set forth how First Amendment procedures have historically protected First Amendment substance and discussed modern applications of the issue. For example, the prior restraint doctrine, overbreadth doctrine, the allocation of the burden of proof and relaxation of ripeness rules have important implications for challenging restrictions on speech and defending against libel and defamation. The interaction of free speech and due process is often seen in litigation involving civil harassment orders, or civil protection orders. In many jurisidictions the definition of harassment permits the finding that harassment can be based solely on speech, meaning speech itself can provide a basis for liabilty. In addition, speech may be restricted as a remedy in litigation addressing harassment. Investigations of wrongdoing in the realm of campaign finance law and political speech cases can also have serious implications for speech, both reputational and legal. Further cases involving political speech and campaign finance once exclusively litigated in the civil arena, are now the subject of criminal investigations and prosecutions. This is particularly problematic where many issues in this area remain unsettled. Good lawyering is particularly important in First Amendment cases. Ineffective assistance of counsel can be considered as great an evil in First Amendment cases as in criminal cases. Unfortunately, practicing lawyers often do not understand the process by which constitutional facts are pleaded and proved in First Amendment cases and this problem begins with the way Constitutional Law 101 is taught in law schools. In proving facts in First Amendment litigation the question becomes how does the government prove its justification of a restriction on speech or how does one opposing the government’s restriction on speech respond when the government asserts certain interests as being their justification. In First Amendment litigation the government often relies on legislative facts – newspaper reports, television stories, and criminal cases discussed in the media, arguably the government should be obligated to present more than rumors and speculation

A comprehensive standardised data definitions set for acute coronary syndrome research in emergency departments in Australasia

Patients with chest discomfort or other symptoms suggestive of acute coronary syndrome are one of the most common categories seen in many Emergency Departments (EDs). Although the recognition of patients at high risk of acute coronary syndrome has improved steadily, identifying the majority of chest pain presentations who fall into the low-risk group remains a challenge. Research in this area needs to be transparent, robust, applicable to all hospitals from large tertiary centres to rural and remote sites, and to allow direct comparison between different studies with minimum patient spectrum bias. A standardized approach to the research framework using a common language for data definitions must be adopted to achieve this. The aim was to create a common framework for a standardized data definitions set that would allow maximum value when extrapolating research findings both within Australasian ED practice, and across similar populations worldwide. Therefore a comprehensive data definitions set for the investigation of non-traumatic chest pain patients with possible acute coronary syndrome was developed, specifically for use in the ED setting. This standardized data definitions set will facilitate‘knowledge translation’ by allowing extrapolation of useful findings into the real-life practice of emergency medicine