709 research outputs found

    Comparing Oyster Seed Growth Rates Using a Floating Upweller System (ā€œFLUPSYā€) vs. Traditional Taylor Floats

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    The fisheries Grant R G 99-20 to Study Oyster seed Growth using a FLUPSY (floating upweller system) vs. traditional bag/float system was a ve1y successful project. We were able after two years to reach interesting and informative conclusions. A Report Summary section is attached following this narrative

    A Multi-Epoch HST Study of the Herbig-Haro Flow from XZ Tauri

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    We present nine epochs of Hubble Space Telescope optical imaging of the bipolar outflow from the pre-main sequence binary XZ Tauri. Our data monitors the system from 1995-2005 and includes emission line images of the flow. The northern lobe appears to be a succession of bubbles, the outermost of which expanded ballistically from 1995-1999 but in 2000 began to deform and decelerate along its forward edge. It reached an extent of 6" from the binary in 2005. A larger and fainter southern counterbubble was detected for the first time in deep ACS images from 2004. Traces of shocked emission are seen as far as 20" south of the binary. The bubble emission nebulosity has a low excitation overall, as traced by the [S II]/H-alpha line ratio, requiring a nearly comoving surrounding medium that has been accelerated by previous ejections or stellar winds. Within the broad bubbles there are compact emission knots whose alignments and proper motions indicate that collimated jets are ejected from each binary component. The jet from the southern component, XZ Tau A, is aligned with the outflow axis of the bubbles and has tangential knot velocities of 70-200 km/s. Knots in the northern flow are seen to slow and brighten as they approach the forward edge of the outermost bubble. The knots in the jet from the other star, XZ Tau B, have lower velocities of ~100 km/s

    A Candidate Brightest Proto-Cluster Galaxy at z = 3.03

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    We report the discovery of a very bright (m_R = 22.2) Lyman break galaxy at z = 3.03 that appears to be a massive system in a late stage of merging. Deep imaging reveals multiple peaks in the brightness profile with angular separations of ~0.''8 (~25 h^-1 kpc comoving). In addition, high signal-to-noise ratio rest-frame UV spectroscopy shows evidence for ~5 components based on stellar photospheric and ISM absorption lines with a velocity dispersion of sigma ~460 km s^-1 for the three strongest components. Both the dynamics and high luminosity, as well as our analysis of a LCDM numerical simulation, suggest a very massive system with halo mass M ~ 10^13 M_solar. The simulation finds that all halos at z = 3 of this mass contain sub-halos in agreement with the properties of these observed components and that such systems typically evolve into M ~ 10^14 M_solar halos in groups and clusters by z = 0. This discovery provides a rare opportunity to study the properties and individual components of z ~ 3 systems that are likely to be the progenitors to brightest cluster galaxies.Comment: 14 pages, 3 figures, submitted to ApJ Letter

    Ariel - Volume 10 Number 3

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    Executive Editors Madalyn Schaefgen David Reich Business Manager David Reich News Editors Medical College Edward Zurad CAHS John Guardiani World Mark Zwanger Features Editors Meg Trexler Jim O\u27Brien Editorials Editor Jeffrey Banyas Photography and Sports Editor Stuart Singer Commons Editor Brenda Peterso

    MODELING STEAM DRYERS

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    ABSTRACT Nuclear steam dryers are used to reduce the moisture carryover (MCO) to levels often well below 0.1%, by weight, water in the steam. The dryers are designed to provide very high quality steam at the full capacity of the steam generator. The purpose of this paper is to present computational fluid dynamics (CFD) models of the steam flow in a generator and the decisions that are required to evaluate different designs. These computational models are successful and proven in field operations

    CAPSTONE: A CubeSat Pathfinder for the Lunar Gateway Ecosystem

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    The cislunar environment is about to get much busier and with this increase in traffic comes an increase in the demand for limited resources such as Earth based tracking of and communications with assets operating in and around the Moon. With the number of NASA, commercial, and international missions to the Moon growing rapidly in the next few years, the need to make these future endeavors as efficient as possible is a challenge that is being solved now. Advanced Space is aiming to mitigate these resource limitations by enabling the numerous spacecraft in the cislunar environment to navigate autonomously and reduce the need for oversubscribed ground assets for navigation and maneuver planning. Scheduled to launch on a Rocket Lab Electron in October 2021, the Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment (CAPSTONE) mission will leverage a 12U CubeSat to demonstrate both the core software for the Cislunar Autonomous Positioning System (CAPS) as well as a validation of the mission design and operations of the Near Rectilinear Halo Orbit (NRHO) that NASA has baselined for the Artemis Lunar Gateway architecture. Currently being developed in a Phase III of NASAā€™s SBIR program, our CAPS software will allow missions to manage themselves and enable more critical communications to be prioritized between Earth and future cislunar missions without putting these missions at increased risk. CAPSTONE is the pathfinder mission for NASAā€™s Artemis program. The overall mission will include collaboration with the Lunar Reconnaissance Orbiter (LRO) operations team at NASA Goddard Space Flight Center to demonstrate inter-spacecraft ranging between the CAPSTONE spacecraft and LRO and with the NASA Gateway Operations team at NASA Johnson Space Center to inform the requirements and autonomous mission operations approach for the eventual Gateway systems. Critical success criteria for CAPSTONE in this demonstration are a transfer to and arrival into an NRHO, semi-autonomous operations and orbital maintenance of a spacecraft in an NRHO, collection of inter-spacecraft ranging data, and execution of the CAPS navigation software system on-board the CAPSTONE spacecraft. Advanced Space along with our partners at NASAā€™s Space Technology Mission Directorate, Advanced Exploration Systems, Launch Services Program, NASA Ames Small Spacecraft Office, Tyvak Nano-Satellite Systems and Rocket Lab, envision the CAPSTONE mission as a key enabler of both NASAā€™s Gateway operations involving multiple spacecraft and eventually the ever-expanding commercial cislunar economy. This low cost, high value mission will demonstrate an efficient low energy orbital transfer to the lunar vicinity and an insertion and operations approach to the NRHO that ultimately will demonstrate a risk reducing validation of key exploration operations and technologies required for the ultimate success of NASAā€™s lunar exploration plans, including the planned human return to the lunar surface. This presentation will include the current mission status (which would include the launch and early mission operations), the operations plan for the NRHO, and lessons learned to date in order to inform future CubeSat pathfinders in support of national exploration and scientific objectives

    2010 YCAP Needs Assessment Report

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    This report outlines the Yamhill Community Action Partnership (YCAP) areas of need, strength, and improvement. Low income and unemployed individuals receive significant support through YCAP programs, including transportation, housing, and bill pay assistance. YCAP programs were assessed during the spring of 2010 through a client survey

    Three-point Correlation Functions of SDSS Galaxies in Redshift Space: Morphology, Color, and Luminosity Dependence

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    We present measurements of the redshift--space three-point correlation function of galaxies in the Sloan Digital Sky Survey (SDSS). For the first time, we analyze the dependence of this statistic on galaxy morphology, color and luminosity. In order to control systematics due to selection effects, we used rr--band, volume-limited samples of galaxies, constructed from the magnitude-limited SDSS data (14.5<r<17.514.5<r<17.5), and further divided the samples into two morphological types (early and late) or two color populations (red and blue). The three-point correlation function of SDSS galaxies follow the hierarchical relation well and the reduced three-point amplitudes in redshift--space are almost scale-independent (Qz=0.5āˆ¼1.0Q_z=0.5\sim1.0). In addition, their dependence on the morphology, color and luminosity is not statistically significant. Given the robust morphological, color and luminosity dependences of the two-point correlation function, this implies that galaxy biasing is complex on weakly non-linear to non-linear scales. We show that simple deterministic linear relation with the underlying mass could not explain our measurements on these scales.Comment: order of figures are changed. 9 pages, 15 figure

    Cell cycle-dependent variations in protein concentration

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    Computational modeling of biological systems has become an effective tool for analyzing cellular behavior and for elucidating key properties of the intricate networks that underlie experimental observations. While most modeling techniques rely heavily on the concentrations of intracellular molecules, little attention has been paid to tracking and simulating the significant volume fluctuations that occur over each cell division cycle. Here, we use fluorescence microscopy to acquire single cell volume trajectories for a large population of Saccharomyces cerevisiae cells. Using this data, we generate a comprehensive set of statistics that govern the growth and division of these cells over many generations, and we discover several interesting trends in their size, growth and protein production characteristics. We use these statistics to develop an accurate model of cell cycle volume dynamics, starting at cell birth. Finally, we demonstrate the importance of tracking volume fluctuations by combining cell division dynamics with a minimal gene expression model for a constitutively expressed fluorescent protein. The significant oscillations in the cellular concentration of a stable, highly expressed protein mimic the observed experimental trajectories and demonstrate the fundamental impact that the cell cycle has on cellular functions

    CAPSTONE: A Summary of Flight Operations to Date in the Cislunar Environment

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    The cislunar environment is about to get much busier and with this increase in traffic comes an increase in the demand for limited resources such as Earth based tracking of and communications with assets operating in and around the Moon. With the number of NASA, commercial, and international missions to the Moon growing rapidly, the need to make these future endeavors as efficient as possible is a challenge that is being solved now. Advanced Space is aiming to mitigate these resource limitations by enabling spacecraft in the cislunar environment to navigate autonomously and reduce the need for oversubscribed ground assets for navigation and maneuver planning. Launched in June 2022, the Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment (CAPSTONE) mission utilizes a 12U CubeSat to demonstrate both the core software for the Cislunar Autonomous Positioning System (CAPS) as well as a validation of the mission design and operations of the Near Rectilinear Halo Orbit (NRHO) that NASA has baselined for the Artemis Lunar Gateway architecture. The CAPS software enables cislunar missions to manage their navigation functions themselves and reduces the reliance on Earth based tracking requirements without putting these missions at increased risk. Upon arrival in the NRHO, the CAPSTONE spacecraft will soon initiate its navigation demonstration mission in collaboration with the Lunar Reconnaissance Orbiter (LRO) operations team at NASAā€™s Goddard Space Flight Center to demonstrate autonomous inter-spacecraft ranging and autonomous navigation between the CAPSTONE spacecraft and LRO. Critical success criteria for CAPSTONE in this demonstration are 1) semi-autonomous operations and orbital maintenance of a spacecraft in an NRHO, 2) collection of inter-spacecraft ranging data, and 3) execution of the CAPS navigation software system in autonomous mode on-board the CAPSTONE spacecraft. Additionally, CAPSTONE continues to demonstrate an innovative one-way ranging navigation approach utilizing a Chip Scale Atomic Clock (CSAC), unique firmware installed on the Iris radio, and onboard autonomous navigation algorithms developed JPL an implemented by Advanced Space. Advanced Space, along with our partners at NASAā€™s Space Technology Mission Directorate, (STMD), Advanced Exploration Systems (AES), Launch Services Program (LSP), NASA Amesā€™ Small Spacecraft Office, the Jet Propulsion Lab (JPL), Terran Orbital and Rocket Lab, envision the CAPSTONE mission as a key enabler of both NASAā€™s upcoming Gateway operations involving multiple spacecraft and eventually the ever-expanding commercial cislunar economy. Over the next 21 months, CAPSTONE will demonstrate an efficient low energy orbital transfer to the lunar vicinity, an insertion into the NRHO, and a risk reducing validation of key exploration operations and technologies required for the ultimate success of NASAā€™s lunar exploration plans. This paper includes an overview of the mission, the current mission operational status, lessons learned from the launch, lunar transfer, and insertion into the NRHO, an overview of operations plan for the NRHO, and other lessons learned to date in order to inform future missions in support of national exploration and scientific objectives
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