Training for muscular power adaptations : the role of contraction type and velocity

Muscular power, an integral component in most sport, is the product of force and velocity. Power is often viewed as synonymous, yet incorrectly, with strength. Where power has an inherent speed component, strength is independent of movement velocity, and is a measure of a muscle’s ability to produce a maximal force. In a majority of athletic events power is requisite to success, and is often more decisive in performance outcomes than strength alone. Currently, results from existing research examining the effectiveness of differing velocities of contraction in improving maximal power are mixed. Common methodologies used in research settings to study muscular power changes are isotonic training, isokinetic training, isometric training, and plyometric training. However, little research has been done examining the potential efficacy of training using inertial loading. This report examines existing research on movement velocities and loads, compares the effects of training velocities for increasing maximal power, identifies shortfalls and information gaps, and recommends future research in training for muscular power adaptations and improved athletic performance. This report also provides a detailed description of inertial load training and establishes a theoretical study design, hypothesis, and reasoning outlining why and how inertial load training may elicit muscular power increases and improved athletic performance.Kinesiology and Health Educatio

Relativistic Broadening of Iron Emission Lines in a Sample of AGN

We present a uniform X-ray spectral analysis of eight type-1 active galactic nuclei (AGN) that have been previously observed with relativistically broadened iron emission lines. Utilizing data from the XMM-Newton European Photon Imaging Camera (EPIC-pn) we carefully model the spectral continuum, taking complex intrinsic absorption and emission into account. We then proceed to model the broad Fe K feature in each source with two different accretion disk emission line codes, as well as a self-consistent, ionized accretion disk spectrum convolved with relativistic smearing from the inner disk. Comparing the results, we show that relativistic blurring of the disk emission is required to explain the spectrum in most sources, even when one models the full reflection spectrum from the photoionized disk.Comment: 50 pages (preprint format), 24 figures. Accepted by Ap

Constraining the Spin of the Black Hole in Fairall 9 with Suzaku

We report on the results of spectral fits made to data obtained from a 168 ksec Suzaku observation of the Seyfert-1 galaxy Fairall 9. The source is clearly detected out to 30 keV. The observed spectrum is fairly simple; it is well-described by a power-law with a soft excess and disk reflection. A broad iron line is detected, and easily separated from distinct narrow components owing to the resolution of the CCDs in the X-ray Imaging Spectrometer (XIS). The broad line is revealed to be asymmetric, consistent with a disk origin. We fit the XIS and Hard X-ray Detector (HXD) spectra with relativistically-blurred disk reflection models. With the assumption that the inner disk extends to the innermost stable circular orbit, the best-fit model implies a black hole spin parameter of a = 0.60(7) and excludes extremal values at a high level of confidence. We discuss this result in the context of Seyfert observations and models of the cosmic distribution of black hole spin.Comment: Accepted for publication in Ap

An Examination of the Spectral Variability in NGC 1365 with Suzaku

We present jointly analyzed data from three deep Suzaku observations of NGC 1365. These high signal-to-noise spectra enable us to examine the nature of this variable, obscured AGN in unprecedented detail on timescales ranging from hours to years. We find that, in addition to the power-law continuum and absorption from ionized gas seen in most AGN, inner disk reflection and variable absorption from neutral gas within the Broad Emission Line Region are both necessary components in all three observations. We confirm the clumpy nature of the cold absorbing gas, though we note that occultations of the inner disk and corona are much more pronounced in the high-flux state (2008) than in the low-flux state (2010) of the source. The onset and duration of the "dips" in the X-ray light curve in 2010 are both significantly longer than in 2008, however, indicating that either the distance to the gas from the black hole is larger, or that the nature of the gas has changed between epochs. We also note significant variations in the power-law flux over timescales similar to the cold absorber, both within and between the three observations. The warm absorber does not vary significantly within observations, but does show variations in column density of a factor of more than 10 on timescales less than 2 weeks that seem unrelated to the changes in the continuum, reflection or cold absorber. By assuming a uniform iron abundance for the reflection and absorption, we have also established that an iron abundance of roughly 3.5 times the solar value is sufficient to model the broad-band spectrum without invoking an additional partial-covering absorber. Such a measurement is consistent with previous published constraints from the 2008 Suzaku observation alone, and with results from other Seyfert AGN in the literature.Comment: 19 pages, 11 figures, accepted for publication in MNRA

Arguments over solutions to the “surge” of Central American immigrant minors are based on myths about why they have come to the U.S.

Recent weeks have seen increasing concern over the “surge” in undocumented minors arriving at the US-Mexico border, with Republicans and Democrats in Congress putting forward potential solutions to the apparent crisis. Robert Brenneman argues that much of the discourse around the border “surge” is based on myths about why unaccompanied minors have come to the US, and whether or not they will be an economic burden if they stay

MEASURING SUPERMASSIVE BLACK HOLE SPINS IN AGN

Measuring the spins of supermassive black holes (SMBHs) in active galactic nuclei (AGN) can inform us about the relative role of gas accretion vs. mergers in recent epochs of the life of the host galaxy and its AGN. Recent theoretical and observation advances have enabled spin measurements for ten SMBHs thus far, but this science is still very much in its infancy. Herein, I discuss how we measure black hole spin in AGN, using recent results from a long Suzaku campaign on NGC 3783 to illustrate this process and its caveats. I then present our current knowledge of the distribution of SMBH spins in the local universe. I also address prospects for improving the accuracy, precision and quantity of these spin constraints in the next decade and beyond with instruments such as NuSTAR, Astro-H and future large-area X-ray telescopes

Tile Spacing Results on Taintor and Kalona Soils

In 1999, a 45-acre tile spacing project was installed adjacent to the Southeast Research Farm. This was done through donations by local drainage contractors, tile companies, and with assistance from the staff at the Southeast Research Farm. The goal was to compare recommended tile spacing (75 ft) with closer tile spacings