Correlations among Multi-Wavelength Luminosities of Star-Forming Galaxies

It has been known for two decades that a tight correlation exists between far-infrared (FIR) and radio (1.4 and 4.8 GHz) global fluxes/luminosities from galaxies, which may be explained in terms of massive star formation activities in these galaxies. For this very reason, a correlation might also exist between X-ray and FIR/radio global luminosities of galaxies. We analyze data from {\it ROSAT} All-Sky Survey and {\it IRAS} to show that such correlation does indeed exist between FIR (42.5$-122.5\mu$m) and soft X-ray (0.1$-$2.4keV) luminosities in active star-forming galaxies (ASFGs).In order to establish a physical connection between the L_{\rmX}-L_{\rm FIR} correlation and global star formation rate (SFR) in galaxies, we empirically derive both $L_{\rm X}-L_{\rm B}$ and $L_{\rm FIR}-L_{\rm B}$ relations. Futhermore, we propose a relation between soft X-ray luminosity and SFR in star-forming galaxies. To further understand the $L_{\rm X}-L_{\rm FIR}$ relation, we construct an empirical model in which both FIR and X-ray emissions consist of two components with one being closely associated with star formation and the other not.Comment: 9 pages, 6 figures, accepted by MNRA

Leiter and Raven Performance and Teacher Ranking: A Correlation Study with Deaf Children

Non

Research and Technology Report. Goddard Space Flight Center

This issue of Goddard Space Flight Center's annual report highlights the importance of mission operations and data systems covering mission planning and operations; TDRSS, positioning systems, and orbit determination; ground system and networks, hardware and software; data processing and analysis; and World Wide Web use. The report also includes flight projects, space sciences, Earth system science, and engineering and materials

Research & Technology Report Goddard Space Flight Center

The main theme of this edition of the annual Research and Technology Report is Mission Operations and Data Systems. Shifting from centralized to distributed mission operations, and from human interactive operations to highly automated operations is reported. The following aspects are addressed: Mission planning and operations; TDRSS, Positioning Systems, and orbit determination; hardware and software associated with Ground System and Networks; data processing and analysis; and World Wide Web. Flight projects are described along with the achievements in space sciences and earth sciences. Spacecraft subsystems, cryogenic developments, and new tools and capabilities are also discussed

Florida Coral Reef Damage from Nuclear Submarine Grounding and Proposed Restoration

The United States submarine Memphis grounded in approximately 10 m water depth on a tropical coral reef ofT southeast Florida in February, 1993. The grounding caused extensive physical and biological damage to the reef substrate and to the coral community. As part of a claim by the State of Florida against the United States, the impact of the grounding was assessed, and the area of damage was determined through field and photographic studies. A recovery rate for the reef was assigned from literature estimates. The NOAA Habitat Equivalency Model (HEM) was used to calculate the reef area needed to be replaced in order to compensate for damages. A plan devised to restore the reef included: removal of loose rubble generated from the grounding; stabilization of reef faces in danger of collapse: emplacement of six different types of artificial reefs; transplantation of reef-building corals (15% of the number damaged) to bare damaged substrate and to the artificial reefs; and a 20 year monitoring period to assess restoration plan efficacy. Settlement of the claim in April, 1997 resulted in an award of $750,000 to the Ecosystem Management Trust Fund of the State of Florida. Utilization of this fund necessitates a revised plan to restore the damaged reef within economic constraints. This plan will involve rubble removal/stabilization, artificial reef emplacement, stony coral transplantation, and monitoring

Identification of a Family of Zinc Transporter Genes from Arabidopsis that Respond to Zinc Deficiency

Millions of people worldwide suffer from nutritional imbalances of essential metals like zinc. These same metals, along with pollutants like cadmium and lead, contaminate soils at many sites around the world. In addition to posing a threat to human health, these metals can poison plants, livestock, and wildlife. Deciphering how metals are absorbed, transported, and incorporated as protein cofactors may help solve both of these problems. For example, edible plants could be engineered to serve as better dietary sources of metal nutrients, and other plant species could be tailored to remove metal ions from contaminated soils. We report here the cloning of the first zinc transporter genes from plants, the ZIP1, ZIP2, and ZIP3 genes of Arabidopsis thaliana. Expression in yeast of these closely related genes confers zinc uptake activities. In the plant, ZIP1 and ZIP3 are expressed in roots in response to zinc deficiency, suggesting that they transport zinc from the soil into the plant. Although expression of ZIP2 has not been detected, a fourth related Arabidopsis gene identified by genome sequencing, ZIP4, is induced in both shoots and roots of zinc-limited plants. Thus, ZIP4 may transport zinc intracellularly or between plant tissues. These ZIP proteins define a family of metal ion transporters that are found in plants, protozoa, fungi, invertebrates, and vertebrates, making it now possible to address questions of metal ion accumulation and homeostasis in diverse organisms

The Grizzly, May 5, 1999

Spring Fling Success • Students Compete in First-Ever Ursinus Drag Competition • Student Speakers Selected • Commencement Program Announced • Mr. Ursinus: Anthony Petrino • Graduation Events Slated: Five Honorary Degrees to be Delivered at Graduation; Baccalaureate Speaker Announced • Let\u27s Throw Some Shoes! • Final Exam Schedule • Ursinus Lacrosse, Baseball Take Centennial Conference by Storm • UC Baseball Dominated the Centennial Conference Behind Great Pitching Performances by Wiatrak and Goldwater • Softball Falls Short of Top Shot • Newmaster Wins Pitcher of the Year • Adegunwa, O\u27Hara Dominate at CC Champs • Best Wishes to Spring Sports Seniorshttps://digitalcommons.ursinus.edu/grizzlynews/1443/thumbnail.jp

Forming supermassive black holes by accreting dark and baryon matter

Given a large-scale mixture of self-interacting dark matter (SIDM) particles and baryon matter distributed in the early Universe, we advance here a two-phase accretion scenario for forming supermassive black holes (SMBHs) with masses around $\sim 10^9 M_{\odot}$ at high redshifts z (\gsim 6). The first phase is conceived to involve a rapid quasi-spherical and quasi-steady Bondi accretion of mainly SIDM particles embedded with baryon matter onto seed black holes (BHs) created at redshifts z\lsim 30 by the first generation of massive Population III stars; this earlier phase rapidly gives birth to significantly enlarged seed BH masses of $M_{\hbox{\tiny BH},t_1}\backsimeq 1.4\times 10^6\ M_\odot \sigma_0/(1\hbox{cm}^2\hbox{g}^{-1})(C_s/30\hbox{km s}^{-1})^4$during$z\sim 20-15$, where$\sigma_0$is the cross section per unit mass of SIDM particles and$C_s$is the velocity dispersion in the SIDM halo referred to as an effective "sound speed". The second phase of BH mass growth is envisaged to proceed primarily via baryon accretion, eventually leading to SMBH masses of$M_{\hbox{\tiny BH}}\sim 10^9 M_\odot$; such SMBHs may form either by$z\sim 6$for a sustained accretion at the Eddington limit or later at lower$z$ for sub-Eddington mean accretion rates. We intend to account for the reported detections of a few SMBHs at early epochs, e.g., SDSS 1148+5251 and so forth, without necessarily resorting to either super-Eddington baryon accretion or very frequent BH merging processes. Only extremely massive dark SIDM halos associated with rare peaks of density fluctuations in the early Universe may harbour such early SMBHs or quasars. Observational consequences are discussed.Comment: 7 pages, 2 figures. accepted by MNRA