Dual load-path fastener

A fastener system is provided for securing a component to supporting structure. The fastener system comprises a pair of cooperating fastener modules. The first module includes a first stationary member attached to the supporting structure and a first bolt member threadedly engaged with the first stationary member. The second module includes a second stationary member also attached to the supporting structure and a second bolt member threadedly engaged with the second stationary member. The second bolt member also extends freely through a longitudinal bore in the first bolt member. Head members on the first and second head members are mutually engaged for their unitary rotation and the first head member engages the component. When the head members are rotated in one direction, they are advanced toward the supporting structure thereby drawing the component toward the supporting structure. Rotation in the opposite direction is effective to cause the head members to retract from the supporting structure and thereby separate the component from the supporting structure. With this construction, upon fracture either of the first fastener means at a location away from the first head member or of the second fastener means at a location away from the second head member, upon rotation of the first head member in the one direction, the first head member nevertheless continues to advance toward the supporting structure

Building the Holocene clinothem in the Gulf of Papua: An ocean circulation study

This paper investigates the role that tidal and wind-driven flows and buoyant river plumes play in the development of the Holocene clinothem in the Gulf of Papua. Time series data from bottom tripods and a mooring were obtained at four locations near the mouth of the Fly River during portions of 2003 and 2004. Flows in the Gulf of Papua during calendar year 2003 were hindcast every 3 h using the Navy Coastal Ocean Model (NCOM) with boundary conditions from the Navy Atmospheric Prediction System, the east Asian seas implementation of NCOM, and the OTIS Tidal Inversion System. Results show that tidal flows on the modern clinoform are strong and are landward and seaward directed. Peak spring tidal velocities can provide the shear stresses necessary to keep sediment up to sand size in motion as the wind-driven and baroclinic currents distribute it from the river mouths across and along the shelf in two circulation states. During the monsoon season, the clinoform topset is swept by a seaward surface flow and landward bottom flow, reflecting river plumes and coastal upwelling. Seaward, this structure evolves into a SW directed surface current over the clinothem foreset with accompanying landward directed near-bed currents that trend obliquely up the foreset to the WSW over much of the clinothem. During the trade wind season, the inner and outer topset are swept by NE directed, contour-parallel surface currents, underneath which lie obliquely landward near-bed currents. These modeled flows and complex gyres in shallow water coupled with wave- and current-supported gravity flows or river floods can explain the form, internal clinoform shapes, and mineralogy of the modern Gulf of Papua clinothem

Stable task information from an unstable neural population

Over days and weeks, neural activity representing an animal’s position and movement in sensorimotor cortex has been found to continually reconfigure or ‘drift’ during repeated trials of learned tasks, with no obvious change in behavior. This challenges classical theories, which assume stable engrams underlie stable behavior. However, it is not known whether this drift occurs systematically, allowing downstream circuits to extract consistent information. Analyzing long-term calcium imaging recordings from posterior parietal cortex in mice (Mus musculus), we show that drift is systematically constrained far above chance, facilitating a linear weighted readout of behavioral variables. However, a significant component of drift continually degrades a fixed readout, implying that drift is not confined to a null coding space. We calculate the amount of plasticity required to compensate drift independently of any learning rule, and find that this is within physiologically achievable bounds. We demonstrate that a simple, biologically plausible local learning rule can achieve these bounds, accurately decoding behavior over many days

The Optical Design of CHARIS: An Exoplanet IFS for the Subaru Telescope

High-contrast imaging techniques now make possible both imaging and spectroscopy of planets around nearby stars. We present the optical design for the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS), a lenslet-based, cryogenic integral field spectrograph (IFS) for imaging exoplanets on the Subaru telescope. The IFS will provide spectral information for 138x138 spatial elements over a 2.07 arcsec x 2.07 arcsec field of view (FOV). CHARIS will operate in the near infrared (lambda = 1.15 - 2.5 microns) and will feature two spectral resolution modes of R = 18 (low-res mode) and R = 73 (high-res mode). Taking advantage of the Subaru telescope adaptive optics systems and coronagraphs (AO188 and SCExAO), CHARIS will provide sufficient contrast to obtain spectra of young self-luminous Jupiter-mass exoplanets. CHARIS will undergo CDR in October 2013 and is projected to have first light by the end of 2015. We report here on the current optical design of CHARIS and its unique innovations.Comment: 15 page

Watershed-Level Responses to Calcium Silicate Treatment in a Northern Hardwood Forest

Watershed 1 (W1) at the Hubbard Brook Experimental Forest in New Hampshire, with chronically low pH and acid neutralizing capacity (ANC) in surface water, was experimentally treated with calcium silicate (CaSiO3; wollastonite) in October 1999 to assess the role of calcium (Ca) supply in the structure and function of base-poor forest ecosystems. Wollastonite addition significantly increased the concentrations and fluxes of Ca, dissolved silica (Si), and ANC and decreased the concentrations and fluxes of inorganic monomeric Al (Ali) and hydrogen ion (H+) in both soil solution and stream water in all sub-watersheds of W1. Mass balances indicate that 54% of the added Ca remained undissolved or was retained by vegetation during the first 6 years after treatment. Of the remaining added Ca, 44% was retained on O horizon cation exchange sites. The Ca:Si ratio in the dissolution products was greater than 2.0, more than twice the molar ratio in the applied wollastonite. This suggests that Ca was preferentially leached from the applied wollastonite and/or Si was immobilized by secondary mineral formation. Approximately 2% of the added Ca and 7% of the added Si were exported from W1 in streamwater in the first 6 years after treatment. Watershed-scale Ca amendment with wollastonite appears to be an effective approach to mitigating effects of acidic deposition. Not only does it appear to alleviate acidification stress to forest vegetation, but it also provides for the long-term supply of ANC to acid-impacted rivers and lakes downstream

Reactor physics project final report

"September 30, 1970."Statement of responsibility on title-page reads: Editors, M. J. Driscoll, I. Kaplan, D. D. Lanning, N. C. Rasmussen. Contributors: V. K. Agarwala, F. M. Clikeman, M. J. Driscoll, Y. Hukai, L. L. Izzo, I. Kaplan, M. S. Kazimi, D.D. Lanning, T.C. Leung, E.L. McFarland, N.C. Rasmussen, S.S. Seth, G.E. Sullivan, and A.T. SuppleIncludes bibliographical referencesFinal report; January 1, 1968 to September 30, 1970This is the final report in an experimental and theoretical program to develop and apply single- and few-element methods for the determination of reactor lattice parameters. The period covered by the report is January 1, 1968 through September 30, 1970. In addition to summarizing results for the entire contract period, this report also serves as the final annual report; thus, work completed in the period of October 1, 1969 through September 30, 1970 is dealt with in more detail than the earlier work. Methods were developed to measure the heterogeneous parameters 17, [Gamma] [eta] and [Alpha] for single fuel elements immersed in moderator in an exponential tank using foil activation measurements external to the fuel. These methods were applied to clustered fuel rods in D 20 moderator and single fuel rods in H 20 moderator, and the results were extended to and compared with data on complete multi-element lattices reported by other laboratories. Advanced gamma spectrometric methods using Ge(Li) detectors were applied to the analysis of both prompt and fission product decay gammas for the nondestructive analysis of the fuel used in this work. The latter includes both simulated burned fuel containing plutonium and actual burned fuel irradiated to 20,000 MWD/T in the Dresden BWR.U.S. Atomic Energy Commission contract AT (30-1)-394

Reactor physics project progress report

Statement of responsibility on title page reads: Editors: M.J. Driscoll and T.J. Thompson; Contributors: F.M. Clikeman, J.N. Donohew, M.J. Driscoll, J.D. Eckard, T.L. Harper, Y. Hukai, I. Kaplan, C.H. Kim, Y.-M. Lefevre, T.C. Leung, N.R. Ortiz, N.C. Rasmussen, C.S. Rim, S.S. Seth, A.T. Supple C. Takahata, and T.J. Thompson"MIT-3944-1."Progress report; September 30, 1968U.S. Atomic Energy Commission contract AT(30-1)-394

PATRIC, the bacterial bioinformatics database and analysis resource

The Pathosystems Resource Integration Center (PATRIC) is the all-bacterial Bioinformatics Resource Center (BRC) (http://www.patricbrc.org). A joint effort by two of the original National Institute of Allergy and Infectious Diseases-funded BRCs, PATRIC provides researchers with an online resource that stores and integrates a variety of data types [e.g. genomics, transcriptomics, protein-protein interactions (PPIs), three-dimensional protein structures and sequence typing data] and associated metadata. Datatypes are summarized for individual genomes and across taxonomic levels. All genomes in PATRIC, currently more than 10 000, are consistently annotated using RAST, the Rapid Annotations using Subsystems Technology. Summaries of different data types are also provided for individual genes, where comparisons of different annotations are available, and also include available transcriptomic data. PATRIC provides a variety of ways for researchers to find data of interest and a private workspace where they can store both genomic and gene associations, and their own private data. Both private and public data can be analyzed together using a suite of tools to perform comparative genomic or transcriptomic analysis. PATRIC also includes integrated information related to disease and PPIs. All the data and integrated analysis and visualization tools are freely available. This manuscript describes updates to the PATRIC since its initial report in the 2007 NAR Database Issu

Exoplanet Science Priorities from the Perspective of Internal and Surface Processes for Silicate and Ice Dominated Worlds

The geophysics of extrasolar planets is a scientific topic often regarded as standing largely beyond the reach of near-term observations. This reality in no way diminishes the central role of geophysical phenomena in shaping planetary outcomes, from formation, to thermal and chemical evolution, to numerous issues of surface and near-surface habitability. We emphasize that for a balanced understanding of extrasolar planets, it is important to look beyond the natural biases of current observing tools, and actively seek unique pathways to understand exoplanet interiors as best as possible during the long interim prior to a time when internal components are more directly accessible. Such pathways include but are not limited to: (a) enhanced theoretical and numerical modeling, (b) laboratory research on critical material properties, (c) measurement of geophysical properties by indirect inference from imprints left on atmospheric and orbital properties, and (d) the purpose-driven use of Solar System object exploration expressly for its value in comparative planetology toward exoplanet-analogs. Breaking down barriers that envision local Solar System exploration, including the study of Earth's own deep interior, as separate from and in financial competition with extrasolar planet research, may greatly improve the rate of needed scientific progress for exoplanet geophysics. As the number of known rocky and icy exoplanets grows in the years ahead, we expect demand for expertise in 'exogeoscience' will expand at a commensurately intense pace. We highlight key topics, including: how water oceans below ice shells may dominate the total habitability of our galaxy by volume, how free-floating nomad planets may often attain habitable subsurface oceans supported by radionuclide decay, and how deep interiors may critically interact with atmospheric mass loss via dynamo-driven magnetic fields