Optical Spectroscopy and Velocity Dispersions of SZ-Selected Galaxy Clusters

We present the design and the first results of a program of optical spectroscopy of galaxies in clusters detected in South Pole Telescope (SPT) data using the Sunyaev-Zel'dovich (SZ) effect, the spectral distortion of the cosmic microwave background from galaxy clusters. We use resampling for an empirical determination of the uncertainty in cluster velocity dispersion calculated from galaxy redshift measurements. We discuss outstanding questions that need answering in order to reach the goal of using cluster velocity dispersion measurements to calibrate scaling relation between the SZ observable and the cluster mass.Physic

Simulation numerique de H₃⁺⁺et H₂⁺ en champ laser intense

Le but premier de ce projet de recherche était de déterminer le plus adéquatement possible les comportements des molécules H₂⁺ et H₃⁺⁺ soumises à un champ laser intense. La première partie du travail a consisté en le calcul en deux dimensions de plusieurs paramètres tels l'ionisation et l'alignement pour la molécule H₂⁺. Les résultats obtenus en deux dimensions étant qualitativement très semblables à ceux connus préalablement en trois dimensions, l'étude a pu s'étendre à une plus grosse molécule, H₃⁺⁺, pour laquelle le comportement était inconnu. Les résultats obtenus permettent également de conclure que l'alignement de la molécule H₂⁺ est possible pour des rayons interatomiques faibles, mais que l'ionisation l'emportait pour de plus grandes distances. Il a été démontré que le taux d'ionisation de H₃⁺⁺ était grandement affecté non seule­ment par le rayon internucléaire, mais également de façon très importante par l'angle d'ouverture de la molécule dans le cas triangulaire. L'explication par un modèle en champ statique a pu être obtenue, démontrant que la localisation des niveaux d'énergie de la molécule était parfaitement compatible avec les résultats obtenus. Enfin, l'étude du couple ressenti par H₃⁺⁺ a permis d'en arriver essentiellement aux mêmes conclusions que pour H₂⁺, à savoir que l'alignement était possible mais seulement pour de faibles distances internucléaires, et que cet alignement impliquerait tout de même deux directions privilégiées perpendiculaires

Problems With Complex Actions

We consider Euclidean functional integrals involving actions which are not exclusively real. This situation arises, for example, when there are $t$-odd terms in the the Minkowski action. Writing the action in terms of only real fields (which is always possible), such terms appear as explicitly imaginary terms in the Euclidean action. The usual quanization procedure which involves finding the critical points of the action and then quantizing the spectrum of fluctuations about these critical points fails. In the case of complex actions, there do not exist, in general, any critical points of the action on the space of real fields, the critical points are in general complex. The proper definition of the function integral then requires the analytic continuation of the functional integration into the space of complex fields so as to pass through the complex critical points according to the method of steepest descent. We show a simple example where this procedure can be carried out explicitly. The procedure of finding the critical points of the real part of the action and quantizing the corresponding fluctuations, treating the (exponential of the) complex part of the action as a bounded integrable function is shown to fail in our explicit example, at least perturbatively.Comment: 6+epsilon pages, no figures, presented at Theory CANADA

Nitrogen Budgets of Phloem-Feeding Bark Beetles with and without Symbiotic Fungi

The nitrogen content of plant tissue is low relative to that of herbivores; as a consequence, dietary N can limit the growth and reproduction of herbivores and select for attributes that increase N acquisition. Bark beetles face a particularly severe challenge because the phloem that they consume is very low in nitrogen and phosphorus relative to their requirements. We quantified variation in the phloem concentrations of N and P in the host tree, Pinus taeda, and evaluated the following hypotheses regarding the role of symbiotic fungi in nutrient budgets of the herbivore Dendroctonus frontalis: D. frontalis experience variation in phloem nutrient concentrations across several spatial scales (H1); mycangial fungi enhance the diet of D. frontalis larvae by contributing to the acquisition of N and P (H2); Ophiostoma minus, an apparently antagonistic fungal symbiont, hinders D. frontalis larvae because it does not enhance nutrient concentrations of the phloem as much as mycangial fungi do (H3); and larvae of bark beetle species that lack mycangial fungi must consume more phloem to accomplish the same growth as larvae of D. frontalis (H4). In addition, we developed a general model for the N budgets of herbivorous insects that identifies the possible combinations of dietary and physiological parameters that can allow developmental success on low‐nutrient diets. Spatial variation in phloem N was mostly at the level of trees within sites (a scale of meters) while P mostly varied among sites (a scale of kilometers). Trees with higher N content produced larger D. frontalis adults. Prior to infestation by beetles, phloem nutrient concentrations were very uniform within trees and very low relative to that of the bark beetles (N and P concentrations of D. frontalis adults were 28 and 8 times greater, respectively). During infestation, phloem nutrient concentrations increased overall and became highly variable within trees. Nitrogen concentrations increased from 0.40 ± 0.01% (mean ± 1 se) in uninfested phloem to 0.86 ± 0.03% in the phloem surrounding successfully developing D. frontalis larvae, which are typically associated with one or two species of mutualistic mycangial fungi. Nitrogen concentrations were intermediate in other microhabitats within infested trees, including regions with no adult colonization, with failed larval development, or colonized by the antagonistic bluestain fungus O. minus. We parameterized a general nutrient‐budget model for D. frontalis and a sympatric non‐mycangial bark beetle, Ips grandicollis, which indicated that (1) mycangial fungi provide their benefits by concentrating dietary N for larvae; (2) O. minus may exert its antagonistic effects on D. frontalis larvae by failing to concentrate dietary N as much as mycangial fungi do; (3) non‐mycangial bark beetles meet their N budgets through high consumption of unaltered, low‐N phloem; and (4) larvae should easily meet their P requirements with any combination of consumption rate and development time that allows them to meet their N requirements. Alternative strategies for N acquisition may have general consequences for the population dynamics and community interactions of bark beetles

Supersensitive Odorant Receptor Underscores Pleiotropic Roles of Indoles in Mosquito Ecology

Mosquitoes exhibit highly diverse and fast evolving odorant receptors (ORs). The indole-sensitive OR gene clade, comprised of Or2 and Or10 is a notable exception on account of its conservation in both mosquito subfamilies. This group of paralogous genes exhibits a complex developmental expression pattern in Aedes aegypti: AaegOr2 is expressed in both adults and larvae, AaegOr10 is adult-specific and a third member named AaegOr9 is larva-specific. OR2 and OR10 have been deorphanized and are selectively activated by indole and skatole, respectively. Using the two-electrode voltage clamp of Xenopus oocytes expressing Ae. aegypti ORs, we show that AaegOR9 is supersensitive and narrowly tuned to skatole. Our findings suggest that Ae. aegypti has evolved two distinct molecular strategies to detect skatole in aquatic and terrestrial environments, highlighting the central ecological roles of indolic compounds in the evolutionary and life histories of these insects

Multi-institution analysis of racial disparity among African- American men eligible for prostate cancer active surveillance

There is a significant controversy on whether race should be a factor in considering active surveillance for low-risk prostate cancer. To address this question, we analyzed a multi-institution database to assess racial disparity between African-American and White-American men with low risk prostate cancer who were eligible for active surveillance but underwent radical prostatectomy. A retrospective analysis of prospectively collected clinical, pathologic and oncologic outcomes of men with low-risk prostate cancer from seven tertiary care institutions that underwent radical prostatectomy from 2003–2014 were used to assess potential racial disparity. Of the 333 (14.8%) African-American and 1923 (85.2%) White-American men meeting active surveillance criteria, African-American men were found to be slightly younger (57.5 vs 58.5 years old; p = 0.01) and have higher BMI (29.3 v 27.9; p \u3c 0.01), pre-op PSA (5.2 v 4.7; p \u3c 0.01), and maximum percentage cancer on biopsy (15.1% v 13.6%; p \u3c 0.01) compared to White-American men. Univariate and multivariate analysis demonstrated similar rates of upgrading, upstaging, positive surgical margin, and biochemical recurrence between races. These results suggest that single institution studies recommending more stringent AS enrollment criteria for AA men with a low-risk prostate cancer may not capture the complete oncologic landscape due to institutional variability in cancer outcomes. Since all seven institutions demonstrated no significant racial disparity, current active surveillance eligibility should not be modified based upon race until a prospective study has been completed. © Dinizo et al

Velocity Segregation and Systematic Biases In Velocity Dispersion Estimates With the SPT-GMOS Spectroscopic Survey

The velocity distribution of galaxies in clusters is not universal; rather, galaxies are segregated according to their spectral type and relative luminosity. We examine the velocity distributions of different populations of galaxies within 89 Sunyaev Zel'dovich (SZ) selected galaxy clusters spanning $0.28 < z < 1.08$. Our sample is primarily draw from the SPT-GMOS spectroscopic survey, supplemented by additional published spectroscopy, resulting in a final spectroscopic sample of 4148 galaxy spectra---2868 cluster members. The velocity dispersion of star-forming cluster galaxies is $17\pm4$% greater than that of passive cluster galaxies, and the velocity dispersion of bright ($m < m^{*}-0.5$) cluster galaxies is $11\pm4$% lower than the velocity dispersion of our total member population. We find good agreement with simulations regarding the shape of the relationship between the measured velocity dispersion and the fraction of passive vs. star-forming galaxies used to measure it, but we find a small offset between this relationship as measured in data and simulations in which suggests that our dispersions are systematically low by as much as 3\% relative to simulations. We argue that this offset could be interpreted as a measurement of the effective velocity bias that describes the ratio of our observed velocity dispersions and the intrinsic velocity dispersion of dark matter particles in a published simulation result. Measuring velocity bias in this way suggests that large spectroscopic surveys can improve dispersion-based mass-observable scaling relations for cosmology even in the face of velocity biases, by quantifying and ultimately calibrating them out.Comment: Accepted to ApJ; 21 pages, 11 figures, 5 table

Metagenomic next-generation sequencing of samples from pediatric febrile illness in Tororo, Uganda.

Febrile illness is a major burden in African children, and non-malarial causes of fever are uncertain. In this retrospective exploratory study, we used metagenomic next-generation sequencing (mNGS) to evaluate serum, nasopharyngeal, and stool specimens from 94 children (aged 2-54 months) with febrile illness admitted to Tororo District Hospital, Uganda. The most common microbes identified were Plasmodium falciparum (51.1% of samples) and parvovirus B19 (4.4%) from serum; human rhinoviruses A and C (40%), respiratory syncytial virus (10%), and human herpesvirus 5 (10%) from nasopharyngeal swabs; and rotavirus A (50% of those with diarrhea) from stool. We also report the near complete genome of a highly divergent orthobunyavirus, tentatively named Nyangole virus, identified from the serum of a child diagnosed with malaria and pneumonia, a Bwamba orthobunyavirus in the nasopharynx of a child with rash and sepsis, and the genomes of two novel human rhinovirus C species. In this retrospective exploratory study, mNGS identified multiple potential pathogens, including 3 new viral species, associated with fever in Ugandan children

Path integration and perturbation theory with complex Euclidean actions

The Euclidean path integral quite often involves an action that is not completely real {\it i.e.} a complex action. This occurs when the Minkowski action contains $t$-odd CP-violating terms. Analytic continuation to Euclidean time yields an imaginary term in the Euclidean action. In the presence of imaginary terms in the Euclidean action, the usual method of perturbative quantization can fail. Here the action is expanded about its critical points, the quadratic part serving to define the Gaussian free theory and the higher order terms defining the perturbative interactions. For a complex action, the critical points are generically obtained at complex field configurations. Hence the contour of path integration does not pass through the critical points and the perturbative paradigm cannot be directly implemented. The contour of path integration has to be deformed to pass through the complex critical point using a generalized method of steepest descent, in order to do so. Typically, what is done is that only the real part of the Euclidean action is considered, and its critical points are used to define the perturbation theory. In this article we present a simple 0+1-dimensional example, of $N$ scalar fields interacting with a U(1) gauge field, in the presence of a Chern-Simons term, where alternatively, the path integral can be done exactly, the procedure of deformation of the contour of path integration can be done explicitly and the standard method of only taking into account the real part of the action can be followed. We show explicitly that the standard method does not give a correct perturbative expansion.Comment: 11 pages, no figures, version to be published in PR

Enhancing Employability for Autistic Graduates: Using TRIZ Theory to Design Virtual Reality Solutions for Fostering Inclusive Communications in Workplace Environments

The underemployment of post-secondary graduates with autism AP-PSD is a critical concern This issue often stems from difficulties in workplace integration and communication This research explores the potential of virtual reality VR systems to alleviate these challenges by simulating work environments The methodology rooted in the TRIZ Theory a problem-solving algorithm refines the use of VR systems for enhanced adaptability and efficiency The primary objectives include enhancing employers understanding of AP-PSD-related issues and identifying significant workplace challenges faced by AP-PSDs Through literature reviews surveys and focus groups the study investigates the factors impacting AP-PSDs and identifies key components to develop a more effective VR system to support their workplace integration The research also scrutinizes existing technological adaptations that could improve situation recognition communication and understanding in the workplace Additionally the potential role of human supervision in conjunction with VR technology support for AP-PSD employees is considered The results suggest that regardless of company size supporting AP-PSDs in the workplace is a feasible goal that can enhance their wellbeing Crucially the AP-PSD s active participation in their own integration process which encompasses training human support and environmental adaptations along with the specific involvement of the human resources manager has proven vital With the right accommodations AP-PSDs can demonstrate up to 30 greater productivity than neurotypical employees offsetting accommodation costs This research emphasizes the need to blend human-centered approaches with technological innovations to boost AP-PSDs employability Though industry-specific integration details are beyond the scope of this study the results underline the potential for tailored solutions aligned with each company s unique culture The paper presents a prototype for further co-design phase