Figures of merit and constraints from testing General Relativity using the latest cosmological data sets including refined COSMOS 3D weak lensing

We use cosmological constraints from current data sets and a figure of merit (FoM) approach to probe any deviations from general relativity (GR) at cosmological scales. The FoM approach is used to study the constraining power of various combinations of data sets on modified gravity (MG) parameters. We use recently refined HST-COSMOS weak-lensing tomography data, ISW-galaxy cross correlations from 2MASS and SDSS LRG surveys, matter power spectrum from SDSS-DR7 (MPK), WMAP7 temperature and polarization spectra, BAO from 2DF and SDSS-DR7, and Union2 compilation of supernovae, in addition to other bounds from H_0 measurements and BBN. We use 3 parametrizations of MG parameters that enter the perturbed field equations. In order to allow for variations with redshift and scale, the first 2 parametrizations use recently suggested functional forms while the third is based on binning methods. Using the first parametrization, we find that CMB + ISW + WL provides the strongest constraints on MG parameters followed by CMB+WL or CMB+MPK+ISW. Using the second parametrization or binning methods, CMB+MPK+ISW consistently provides some of the strongest constraints. This shows that the constraints are parametrization dependent. We find that adding up current data sets does not improve consistently uncertainties on MG parameters due to tensions between best-fit MG parameters preferred by different data sets. Furthermore, some functional forms imposed by the parametrizations can lead to an exacerbation of these tensions. Next, unlike some studies that used the CFHTLS lensing data, we do not find any deviation from GR using the refined HST-COSMOS data, confirming previous claims in those studies that their result may have been due to some systematic effect. Finally, we find in all cases that the values corresponding to GR are within the 95% confidence level contours for all data set combinations. (abridged)Comment: 18 pages, 6 figures, matches version published in PR

Fine-scale taxonomic and spatiotemporal variability in the energy density of prey for juvenile Chinook salmon (Oncorhynchus tshawytscha)

The growth and survival of juvenile Chinook salmon (Oncorhynchus tshawytscha) are determined in part by biotic and abiotic conditions experienced during their first marine summer. Of the biotic conditions, the quality of available prey is integral for optimal growth and survival. Current studies that investigate the effect of variable prey quality on salmon growth approximate energy density using literature values. This approach ignores fine-scale taxonomic as well as spatial and temporal differences in prey quality. To address these possible sources of error, monthly zooplankton tows were performed in Saanich Inlet, Cowichan Bay and Maple Bay off the coast of Vancouver Island, British Columbia in the summer of 2017. Individuals were separated to the species level and wet, dry and ash weights were measured for each zooplankter. Energy density was calculated from an established model, which relates the ash-free dry weight of individuals to energy density values. Early results suggest statistically significant differences in energy density between several species of hyperiid amphipods, which represent a large proportion of O. tshawytscha diet in some years. Other important species groups such as euphausiids, crab zoea and gammerid amphipods differed in energy density from previously reported studies in other locations suggesting spatial variability in energy density. These early results suggest that fine-scale taxonomic variability in energy density exists and that species-specific energy density may vary across space and time. Studies that draw conclusions from literature values of energy density without direct measurement should be cautious in extrapolating with these data in relation to their study system

Do Newton's G and Milgrom's a_0 vary with cosmological epoch ?

In the scalar tensor gravitational theories Newton's constant G_N evolves in the expanding universe. Likewise, it has been speculated that the acceleration scale a_0 in Milgrom's modified Newtonian dynamics (MOND) is tied to the scale of the cosmos, and must thus evolve. With the advent of relativistic implementations of the modified dynamics, one can address the issue of variability of the two gravitational ''constants'' with some confidence. Using TeVeS, the Tensor-Vector-Scalar gravitational theory, as an implementation of MOND, we calculate the dependence of G_N and a_0 on the TeVeS parameters and the coeval cosmological value of its scalar field, \phi_c. We find that G_N, when expressed in atomic units, is strictly nonevolving, a result fully consistent with recent empirical limits on the variation of G_N. By contrast, we find that a_0 depends on \phi_c and may thus vary with cosmological epoch. However, for the brand of TeVeS which seems most promising, a_0 variation occurs on a timescale much longer than Hubble's, and should be imperceptible back to redshift unity or even beyond it. This is consistent with emergent data on the rotation curves of disk galaxies at significants redshifts.Comment: 9 pages, RevTe

Density and Velocity Fields from the PSCz Survey

We present the results for the predicted density and peculiar velocity fields and the dipole from the PSCz survey of 15,000 IRAS galaxies over 84% of the sky. We find a significant component to the dipole arising between 6000 and 15,000 km/s, but no significant component from greater distances. The misalignment with the CMB is 20 degrees. The most remarkable feature of the PSCz model velocity field is a coherent large-scale flow along the baseline connecting Perseus-Pisces, the Local Supercluster, Great Attractor and the Shapley Concentration. We have measured the parameter beta using the amplitude of the dipole, bulk flow and point by point comparisons between the individual velocities of galaxies in the MarkIII and SFI datasets, and the large-scale clustering distortion in redshift space.All our results are consistent with beta = 0.6 +- 0.1.Comment: 8 pages, 8 figures. To appear in 'Towards an Understanding of Cosmic Flows', Victoria, July 1999, eds Courteau,S., Strauss,M., Willick,J. PAS

CT Imaging In The Anatomy Lab

Abstract: Competency in basic radiology is an essential skill for graduating physicians. In preclinical courses at Larner College of Medicine, imaging instruction is delivered via asynchronous modules and on still images. Student feedback indicated a need for improved exposure to radiology at an earlier stage of training. This project was developed to improve first-year medical students’ ability to interpret cross-sectional imaging and aid students’ learning of anatomy by introducing CT scans into the gross anatomy lab. To guide future directions of this curricular development and the potential development of best practices for other schools interested in using similar techniques, this study was designed to assess if there is an advantage or perceived benefit to learning on CT scans of cadavers versus scans of living individuals. Students were placed in three CT groups: CT Group 1 learned from images of the cadaver they were dissecting; CT Group 2 learned from images of a cadaver they were not dissecting; CT Group 3 learned from non-contrast images of a normal living individual. CT scans were uploaded to Pacsbin, a web-based DICOM viewer, and were accessible to students on iPads in anatomy lab and outside of lab on personal devices. Students learned how to utilize common DICOM features as well as how to identify and label anatomical structures through instructor-led e-modules. During lab dissection, students were assisted in the use of Pacsbin and identification of anatomical structures on CT scans by Radiology residents. Student knowledge was assessed on laboratory practical exams and CT image questions were administered via iPads, allowing students to view labeled structures in sagittal, coronal, or axial planes. This intervention was implemented only for the thorax and abdomen portions of the anatomy curriculum. Students were assessed specifically on their overall anatomy practical performance, the ability to correctly identify structures on cross-sectional images, and the ability to correctly identify spatial anatomical relationships. Surveys were administered before and after the intervention to evaluate students’ perceptions of their anatomical, pathological, and cross-sectional imaging knowledge, as well as student satisfaction with the intervention. Results did not reveal a statistically significant difference between the three study groups in practical examination scores, ability to correctly identify anatomical structures on CT images, or spatial anatomical knowledge. When compared with the performance of the previous class, there were no significant differences in practical exam scores for the thorax and abdomen. Survey data showed that students received the intervention positively. Students indicated improved anatomical and imaging knowledge after the course and most students reported feeling better prepared to use imaging software and interpret diagnostic imaging. Conclusions There was no academic advantage observed on practical exams between groups learning cross-sectional imaging from CT scans of cadavers versus living individuals. Positive outcomes were observed as a result of the intervention, as students reported improvements in anatomical knowledge, ability to interpret CT images, and utilize DICOM viewers similar to those seen in the clinical environment. While others have used post-mortem CT imaging in anatomy, none to our knowledge have compared it with scans from living individuals or made DICOM viewers available at each student table. IRB: Study0000213

Junior Recital: Jeremy Perkins, trumpet

This recital is presented in partial fulfillment of requirements for the degree Bachelor of Music in Performance. Mr. Perkins studies trumpet with Douglas Lindsey.https://digitalcommons.kennesaw.edu/musicprograms/2088/thumbnail.jp

Senior Recital: Jacob Greifinger, trumpet

This recital is presented in partial fulfillment of requirements for the degree Bachelor of Music in Performance. Mr. Greifinger studies trumpet with Michael Tiscione.https://digitalcommons.kennesaw.edu/musicprograms/2224/thumbnail.jp