One-and-dones : A Data Science Analysis of the Impact of Leaving College Early for the NBA on a Player\u27s Career

College basketball is a highly popular sport and, in the wake of March Madness, one wonders what will happen to key players next year. The National Basketball Association (NBA) currently restricts players from entering the draft until they are 19. This leads some players to enter college simply as a practice and waiting area for the NBA. These players - often termed one-and-dones - stay for a year and then at their earliest chance, enter the draft. I wondered if staying in college longer allows NBA-bound players more practice and experience playing under pressure, or if players were better off by leaving college early to play while they were still young. Using R, I gathered individual player data from both college and the NBA. This required significant work in gathering, fusing, and cleansing electronic data from multiple sources into a usable form. I then investigated various accepted performance aggregation metrics, and settled on efficiency (EFF) which is a relatively simple measure that consolidates a player\u27s yearly performance (including points, rebounds, assists, etc.) into a single number. Using machine learning techniques, I divided the players into clusters (small groups of statistically similar players) based on their freshman-year data and then examined each cluster individually. For each cluster, I analyzed whether there was a significant difference between the one-and-dones and the others. In this way I could examine the likely effect that additional college experience would have had on a player\u27s NBA career. This analysis found little significance between the one-and-dones and the more-and-dones , meaning perhaps a player\u27s NBA performance is not hurt by coming out early

Black hole-neutron star mergers: effects of the orientation of the black hole spin

The spin of black holes in black hole-neutron star (BHNS) binaries can have a strong influence on the merger dynamics and the postmerger state; a wide variety of spin magnitudes and orientations are expected to occur in nature. In this paper, we report the first simulations in full general relativity of BHNS mergers with misaligned black hole spin. We vary the spin magnitude from a/m=0 to a/m=0.9 for aligned cases, and we vary the misalignment angle from 0 to 80 degrees for a/m=0.5. We restrict our study to 3:1 mass ratio systems and use a simple Gamma-law equation of state. We find that the misalignment angle has a strong effect on the mass of the postmerger accretion disk, but only for angles greater than ~ 40 degrees. Although the disk mass varies significantly with spin magnitude and misalignment angle, we find that all disks have very similar lifetimes ~ 100ms. Their thermal and rotational profiles are also very similar. For a misaligned merger, the disk is tilted with respect to the final black hole's spin axis. This will cause the disk to precess, but on a timescale longer than the accretion time. In all cases, we find promising setups for gamma-ray burst production: the disks are hot, thick, and hyperaccreting, and a baryon-clear region exists above the black hole.Comment: 15 pages, 13 figure

Jetstream: A Distributed Cloud Infrastructure for Under-resourced Higher Education Communities

The US National Science Foundation (NSF) in 2015 awarded funding for a first-of-a-kind distributed cyberinfrastructure (DCI) system called Jetstream. Jetstream will be the NSF’s first production cloud for general-purpose science and engineering research and education. Jetstream, scheduled for production in January 2016, will be based on the OpenStack cloud environment software with a menu-driven interface to make it easy for users to select a pre-composed Virtual Machine (VM) to perform a particular discipline-specific analysis. Jetstream will use the Atmosphere user interface developed as part of iPlant, providing a low barrier to use by practicing scientists, engineers, educators, and students, and Globus services from the University of Chicago for seamless integration into the national cyberinfrastructure fabric. The team implementing Jetstream has as their primary mission extending the reach of the NSF’s eXtreme Digital (XD) program to researchers, educators, and research students who have not previously used NSF XD program resources, including those in communities and at institutions that traditionally lack significant cyberinfrastructure resources. We will, for example, use virtual Linux Desktops to deliver DCI capabilities supporting research and research education at small colleges and universities, including Historically Black Colleges and Universities (HBCUs), Minority Serving Institutions (MSIs), Tribal colleges, and higher education institutions in states designated by the NSF as eligible for funding via the Experimental Program to Stimulate Competitive Research (EPSCoR). Jetstream will be a novel distributed cyberinfrastructure, with production components in Indiana and Texas. In particular, Jetstream will deliver virtual Linux desktops to tablet devices and PDAs with reasonable responsiveness running over cellular networks. This paper will discuss design and application plans for Jetstream as a novel Distributed CyberInfrastructure system for research education.National Science Foundation (NSF) grant ACI-1445604. NSF grant OCI-1053575 for campus bridging activitie

Split-Marker Recombination for Efficient Targeted Deletion of Fungal Genes

A commonly used method for fungal gene deletion is introduction of linear DNA consisting of a selectable marker gene flanked on both sides by short stretches of DNA that target a gene of interest (Wirsel et al 1996 Curr. Genet 29:241-249). Gene deletion in Cochliobolus heterostrophus and Gibberella zeae occurs efficiently with this approach. To facilitate deletion construct synthesis, we have applied the split-marker” deletion strategy previously developed for Saccharomyces cerevisiae (Fairhead et al. 1996 Yeast 12:1439-57; Fairhead et al. 1998 Gene 223:33-46). Here, we describe both fusion PCR-based and plasmid-based deletion methods using this strategy with PEG-mediated protoplast transformation (Turgeon et al, 1985 Mol. Gen. Genet. 201:450-453). These methods are predicted to work well with any transformable fungus that undergoes homologous recombination between chromosomal and introduced DNA sequences

Multiscale Modeling of Binary Polymer Mixtures: Scale Bridging in the Athermal and Thermal Regime

Obtaining a rigorous and reliable method for linking computer simulations of polymer blends and composites at different length scales of interest is a highly desirable goal in soft matter physics. In this paper a multiscale modeling procedure is presented for the efficient calculation of the static structural properties of binary homopolymer blends. The procedure combines computer simulations of polymer chains on two different length scales, using a united atom representation for the finer structure and a highly coarse-grained approach on the meso-scale, where chains are represented as soft colloidal particles interacting through an effective potential. A method for combining the structural information by inverse mapping is discussed, allowing for the efficient calculation of partial correlation functions, which are compared with results from full united atom simulations. The structure of several polymer mixtures is obtained in an efficient manner for several mixtures in the homogeneous region of the phase diagram. The method is then extended to incorporate thermal fluctuations through an effective chi parameter. Since the approach is analytical, it is fully transferable to numerous systems.Comment: in press, 13 pages, 7 figures, 6 table

First-principles study of phase stability of Gd-doped EuO and EuS

Phase diagrams of isoelectronic Eu$_{1-x}$Gd$_x$O and Eu$_{1-x}$Gd$_{x}$S quasi-binary alloy systems are constructed using first-principles calculations combined with the standard cluster expansion approach and Monte-Carlo simulations. The oxide system has a wide miscibility gap on the Gd-rich side but forms ordered compounds on the Eu-rich side, exhibiting a deep asymmetric convex hull in the formation enthalpy diagram. The sulfide system has no stable compounds. The large difference in the formation enthalpies of the oxide and sulfide compounds is due to the contribution of local lattice relaxation, which is sensitive to the anion size. The solubility of Gd in both EuO and EuS is in the range of 10-20% at room temperature and quickly increases at higher temperatures, indicating that highly doped disordered solid solutions can be produced without the precipitation of secondary phases. We also predict that rocksalt GdO can be stabilized under appropriate experimental conditions.Comment: 14 pages, 6 figures (some with multiple panels), revtex4 with embedded ep

A First Principle Approach to Rescale the Dynamics of Simulated Coarse-Grained Macromolecular Liquids

We present a detailed derivation and testing of our approach to rescale the dynamics of mesoscale simulations of coarse-grained polymer melts (I. Y. Lyubimov et al. J. Chem. Phys. \textbf{132}, 11876, 2010). Starting from the first-principle Liouville equation and applying the Mori-Zwanzig projection operator technique, we derive the Generalized Langevin Equations (GLE) for the coarse-grained representations of the liquid. The chosen slow variables in the projection operators define the length scale of coarse graining. Each polymer is represented at two levels of coarse-graining: monomeric as a bead-and-spring model and molecular as a soft-colloid. In the long-time regime where the center-of-mass follows Brownian motion and the internal dynamics is completely relaxed, the two descriptions must be equivalent. By enforcing this formal relation we derive from the GLEs the analytical rescaling factors to be applied to dynamical data in the coarse-grained representation to recover the monomeric description. Change in entropy and change in friction are the two corrections to be accounted for to compensate the effects of coarse-graining on the polymer dynamics. The solution of the memory functions in the coarse-grained representations provides the dynamical rescaling of the friction coefficient. The calculation of the internal degrees of freedom provides the correction of the change in entropy due to coarse-graining. The resulting rescaling formalism is a function of the coarse-grained model and thermodynamic parameters of the system simulated. The rescaled dynamics obtained from mesoscale simulations of polyethylene, represented as soft colloidal particles, by applying our rescaling approach shows a good agreement with data of translational diffusion measured experimentally and from simulations. The proposed method is used to predict self-diffusion coefficients of new polyethylene samples.Comment: 21 pages, 6 figures, 6 tables. Submitted to Phys. Rev.

Lattice Study of Conformal Behavior in SU(3) Yang-Mills Theories

Using lattice simulations, we study the extent of the conformal window for an SU(3) gauge theory with N_f Dirac fermions in the fundamental representation. We extend our recently reported work, describing the general framework and the lattice simulations in more detail. We find that the theory is conformal in the infrared for N_f = 12, governed by an infrared fixed point, whereas the N_f = 8 theory exhibits confinement and chiral symmetry breaking. We therefore conclude that the low end of the conformal window N_f^c lies in the range 8 <= N_f^c <= 12. We discuss open questions and the potential relevance of the present work to physics beyond the standard model.Comment: 37 pages, 7 figures. v2: assorted minor updates and correction