No clear Y2K roadmap can be costly; may create serious liability.

PubMed

1998-12-01

Hospitals without Year 2000 plans in place could be setting themselves up for costly equipment failure. Learn what the experts say about prioritizing to ensure patient care isn't disrupted, and find out about testing medical devices and equipment for Y2K compliance, and what to consider when setting up a Y2K analysis program in your hospital, including how to ensure vendors tell you the truth about whether their products are Y2K compliant.

FDA publishes checklist of Y2K high-risk devices.

PubMed

1999-09-01

Key points. The federal Food and Drug Administration (FDA) has developed a list of types of medical devices that have the potential for the most serious consequences for patients should they fail because of Y2K-related problems. This list of computer-controlled potentially high-risk devices can provide a guide to health care facilities regarding the types of devices that should receive priority in their assessment and remediation of medical devices. The list may change as the FDA receives comments on the types of devices included in the list.

Y2K and International Agricultural Transportation: Analysis of Export Markets, Import Suppliers, and Major Food Aid Recipient Countries

DOT National Transportation Integrated Search

1999-09-01

USDA Y2K information assessment of international food transportation modes in : selected foreign countries. The assessment targeted 9 of the top 10 markets for : U.S. Agricultural exports and 7 of the top 8 suppliers of imported food products : to th...

K(Ca)3.1 channels facilitate K+ secretion or Na+ absorption depending on apical or basolateral P2Y receptor stimulation.

PubMed

Palmer, Melissa L; Peitzman, Elizabeth R; Maniak, Peter J; Sieck, Gary C; Prakash, Y S; O'Grady, Scott M

2011-07-15

Human mammary epithelial (HME) cells express several P2Y receptor subtypes located in both apical and basolateral membranes. Apical UTP or ATP-γ-S stimulation of monolayers mounted in Ussing chambers evoked a rapid, but transient decrease in short circuit current (I(sc)), consistent with activation of an apical K+ conductance. In contrast, basolateral P2Y receptor stimulation activated basolateral K+ channels and increased transepithelial Na+ absorption. Chelating intracellular Ca2+ using the membrane-permeable compound BAPTA-AM, abolished the effects of purinoceptor activation on I(sc). Apical pretreatment with charybdotoxin also blocked the I(sc) decrease by >90% and similar magnitudes of inhibition were observed with clotrimazole and TRAM-34. In contrast, iberiotoxin and apamin did not block the effects of apical P2Y receptor stimulation. Silencing the expression of K(Ca)3.1 produced ∼70% inhibition of mRNA expression and a similar reduction in the effects of apical purinoceptor agonists on I(sc). In addition, silencing P2Y2 receptors reduced the level of P2Y2 mRNA by 75% and blocked the effects of ATP-γ-S by 65%. These results suggest that P2Y2 receptors mediate the effects of purinoceptor agonists on K+ secretion by regulating the activity of K(Ca)3.1 channels expressed in the apical membrane of HME cells. The results also indicate that release of ATP or UTP across the apical or basolateral membrane elicits qualitatively different effects on ion transport that may ultimately determine the [Na+]/[K+] composition of fluid within the mammary ductal network.

Cas A-A Y2K status report

NASA Astrophysics Data System (ADS)

Rudnick, L.

2001-05-01

Cas A has continued to be a rich source of information as new telescopes and detailed observations have become available. In this Y2K update, I focus on the observational findings over the last five years in the areas of ejecta mapping, hydrodynamic structure and kinematics, and high energy particles. Readers are unfortunately left to their own devices on the intriguing point source. .

Many States unprepared for 'Y2K' computer woes.

PubMed

1998-12-25

Most computer systems that States use to process health benefits are not Y2K compliant, which could jeopardize Medicaid application processing. This could cause recipients to lose benefits or experience delays in payments. Only seven states have reported that their systems are ready for the year 2000. Contact information is provided.

The 'Y2K bug': how to ease hospital equipment into the next millennium.

PubMed

Moyer, P

1998-01-01

The advent of the 21st century is unlikely to wreak as much technologic havoc as the doomsayers have predicted. The Y2K problem is addressed by new programs that use a four-digit year code. Although hospitals must prioritize technology for Y2K compliance, they also need to address the issue actively: 2000 is less than 18 months away!

Y2K: prepare, don't panic.

PubMed

Russo, R

1999-04-01

Y2K issues could affect anyone, so it is important for HIV-positive people to make preparations to ensure their health and security. There are wide-ranging opinions about the effects of the so-called Millennium Bug, but some planning will make any changes more manageable. Patients should have adequate supplies of food, water, and medications at home in case of shortages or production problems. Other prudent steps include keeping extra cash on hand and obtaining copies of medical records and benefit plans. Internet resources are listed.

Exoplanets in the M2K Survey

NASA Astrophysics Data System (ADS)

Boyajian, Tabetha; Fischer, Debra; Gaidos, Eric; Giguere, Matt

2013-07-01

Late type stars are ideal targets for the detection of low-mass planets residing in habitable zones. In such systems, not only is the stellar noise a minimum, but the lower stellar mass affords larger reflex velocities and the lower stellar luminosity moves the habitable zone inward. The M2K program is a high precision Doppler survey monitoring a couple hundred late-type stars over the past few years in search for such important exoplanetary systems. We present updated orbits of known exoplanet systems and newly detected exoplanet systems that have resulted from this program. We also advertise the Planethunters.org "Guest Scientist" program as well as our survey to measure stellar diameters and temperatures with long baseline optical interferometry.

The Composition of the Y2K Meteor

NASA Astrophysics Data System (ADS)

Coulson, S. G.

During the Leonid meteor shower of November 1999 a very bright meteor train, subsequently called the Y2K meteor, was observed. Analysis of the trajectory of the meteor suggests that it was composed of two distinct materials. The bulk of the meteor was composed of a comet-like material, while a much smaller fraction was of a denser carbonaceous material. A simple model is used to analytically determine the mass of the meteor fragments.

Hang in there! Quick takes on Y2K.

PubMed

Lewis, A G; Weingart, V S

1998-11-01

Cliffhangers in movies are great fun. But not in real life. Think Y2K. If you haven't scripted a way to beat the millennium bug, there are workable solutions that can be created in six months. Here's how to begin production: Prioritize activities, expenditures and resources, and apply them to the most vital problems first.

VizieR Online Data Catalog: Team Keck Redshift Survey 2 (TKRS2) (Wirth+, 2015)

NASA Astrophysics Data System (ADS)

Wirth, G. D.; Trump, J. R.; Barro, G.; Guo, Y.; Koo, D. C.; Liu, F.; Kassis, M.; Lyke, J.; Rizzi, L.; Campbell, R.; Goodrich, R. W.; Faber, S. M.

2016-04-01

We present the Team Keck Redshift Survey 2 (TKRS2), a spectroscopic survey of 97 distant galaxies exploiting the capabilities of the Multi-Object Spectrometer For Infra-Red Exploration (MOSFIRE) on the Keck I telescope at the W. M. Keck Observatory. MOSFIRE features a 2048*2048 pixel HAWAII-2RG HgCdTe detector array from Teledyne Imaging Sensors that couples high quantum efficiency with low noise and low dark current. The operating range of 0.97-2.41μm covers the YJHK infrared passbands, with wavelength coverage of 0.97-1.12μm in Y, 1.15-1.35μm in J, 1.47-1.80μm in H, and 1.95-2.40μm in K. The resolving power for the default slit width of 0.7" is R=3380 in Y, 3310 in J, 3660 in H, and 3620 in K, corresponding to full-width-half-maximum (FWHM) spectral resolutions of 3.1Å in Y, 3.7Å in J, 4.4Å in H, and 6.0Å in K. Our survey targets the south-central region of the GOODS-North survey field (Giavalisco et al. 2004, cat. II/261). We employed MOSFIRE to acquire spectra in the GOODS-North field over a series of partial nights spanning the period from 2012 November to 2013 May. We present the results of our survey in Table3 and on the website (http://arcoiris.ucsc.edu/TKRS2/) devoted to the survey. (1 data file).

2. Historic American Buildings Survey Everitt K. Taylor, Photographer September ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. Historic American Buildings Survey Everitt K. Taylor, Photographer September 15, 1936 EXTERIOR - EAST ELEVATION FROM OLD PRINT IN POSSESSION OF OWNER - Governor's House, 149 Kearny Avenue, Perth Amboy, Middlesex County, NJ

JPL Year 2000 Project. A Project Manager's Observations: Y2k

NASA Technical Reports Server (NTRS)

Mathison, Richard P. (Technical Monitor)

1999-01-01

This paper presents observations from a project manager on the Y2K problem. The topics include: 1) Agenda: 2) Scope; 3) Project Organization; 4) The Fixes; 5) The Toughest Part; 6) Validation versus Time; and 7) Information Sources. This paper is in viewgraph form.

Y2K, embedded chips, casualty hazards and due diligence in healthcare risk management.

PubMed

Childers, J R

1998-01-01

Y2K raises challenges for healthcare risk managers that go beyond information technology issues. This article explains that (1) too little public attention is being paid to equipment which may well have Y2K faults and (2) few standards have been articulated for dealing with problems. Healthcare risk managers therefore must return to basic due diligence principles and develop their own standards and protocols. The article explains how to do due diligence and outlines suggested steps for dealing with the non-information technology side of compliance due diligence.

A manufacturer's perspective: Hewlett Packard Y2K action plan.

PubMed

Rapp, W N

1999-01-01

Medical device manufacturers must ensure that their devices are safe and effective including investigating issues involved with the century rollover. Manufacturers must begin early to evaluate their products in order to allow time to correct and distribute these product corrections and communicate to their customers so they can prepare for the Y2K event.

How to apply Y2K lessons to patient confidentiality.

PubMed

2001-04-01

Despite current debate over the details of implementing the privacy portion of the Health Insurance Portability and Accountability Act (HIPAA) of 1996, experts say quality managers should continue their planning to comply with the new law. One way to prepare for the sweeping new mandates is to apply the lessons of Y2K to HIPAA.

Insulating and metallic spin glass in K xFe 2-δ-yNi ySe 2 (0.06 ≤ y ≤ 1.44 ) single crystals

DOE PAGES

Ryu, Hyejin; Abeykoon, Milinda; Wang, Kefeng; ...

2015-05-04

We report electron doping effects by Ni in K xFe 2-δ-yNi ySe₂ (0.06 ≤ y ≤ 1.44) single crystal alloys. A rich ground state phase diagram is observed. Thus, a small amount of Ni (~ 4%) suppressed superconductivity below 1.8 K, inducing insulating spin glass magnetic ground state for higher Ni content. With further Ni substitution, metallic resistivity is restored. For high Ni concentration in the lattice the unit cell symmetry is high symmetry I4/ mmm with no phase separation whereas both I4/ m + I4/ mmm space groups were detected in the phase separated crystals when concentration of Nimore » < Fe. The absence of superconductivity coincides with the absence of crystalline Fe vacancy order.« less

Synthesis of the new quaternary sulfides K[sub 2]Y[sub 4]Sn[sub 2]S[sub 11] and BaLnAgS[sub 3] (Ln = Er, Y, Gd) and the structures of K[sub 2]Y[sub 4]Sn[sub 2]S[sub 11] and BaErAgS[sub 3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Ping; Ibers, J.A.

1994-05-01

Several new quarternary sulfides, K[sub 2]Y[sub 4]Sn[sub 2]S[sub 11] and BaLnAgS[sub 3] (Ln = Er, Y, Gd), have been synthesized by the reaction of the constituent binary chalcogenides and elements at 1000[degrees]C. The crystal structures of K[sub 2]Y[sub 4]Sn[sub 2]S[sub 11] and BaErAgS[sub 3] have been determined by single-crystal X-ray diffraction techniques. Crystal data: K[sub 2]Y[sub 4]Sn[sub 2]S[sub 11]-space group D[sup 8][sub 4h] - P4/ncc, M = 1023.88, Z = 4, a = 8.587(1), c = 27.892(4) [angstrom] (T = 115 K), V = 2056.7(4) [angstrom][sup 3], R[sub W](F[sup 2]) = 0.093 for 1965 observations having F[sup 2][sub 0] >more » 2[sigma](F[sup 2][sub 0]); BaEr AgS[sub 3]-space group C[sup 3][sub 2H] - C2/m, M = 508.65, Z = 4, a = 17.340(4), b = 4.014(1), x = 8.509(2) [angstrom], [beta] = 103.23(3)[degrees], (T = 115 K), V = 576.5(2) [angstrom][sup 3], R[sub W](F[sup 2]) = 0.049 for 1404 observations and 48 variables, R(F) = 0.018 for 1299 observations having F[sup 2][sub 0] > 2[sigma](F[sup 2][sub 0]). In both structures, the rare-earth atoms have octahedral coordination and the octahedra form slabs through edge- and corner-sharing. These slabs are separated by K[sup +] Ba[sup 2+] cations, and are crosslinked into three-dimensional frameworks by Sn[sub 2]S[sub 6] units as edge-sharing SnS[sub 4] tetrahedral pairs in K[sub 2]Y[sub 4]Sn[sub 2]S[sub 11], and by Ag[sub 2]S[sub 9] units as corner-sharing trigonal-bipyramidal AgS[sub 5] pairs in BaEr AgS[sub 3]. From their powder diffraction patterns, BaYAgS[sub 3] and Ba GdAgS[sub 3] appear to be isostructural with BaErAgS[sub 3].« less

The USNO-UKIRT K-band Hemisphere Survey

NASA Astrophysics Data System (ADS)

Dahm, Scott; Bruursema, Justice; Munn, Jeffrey A.; Vrba, Fred J.; Dorland, Bryan; Dye, Simon; Kerr, Tom; Varricatt, Watson; Irwin, Mike; Lawrence, Andy; McLaren, Robert; Hodapp, Klaus; Hasinger, Guenther

2018-01-01

We present initial results from the United States Naval Observatory (USNO) and UKIRT K-band Hemisphere Survey (U2HS), currently underway using the Wide Field Camera (WFCAM) installed on UKIRT on Maunakea. U2HS is a collaborative effort undertaken by USNO, the Institute for Astronomy, University of Hawaii, the Cambridge Astronomy Survey Unit (CASU) and the Wide Field Astronomy Unit (WFAU) in Edinburgh. The principal objective of the U2HS is to provide continuous northern hemisphere K-band coverage over a declination range of δ=0o – +60o by combining over 12,700 deg2 of new imaging with the existing UKIRT Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS), Galactic Plane Survey (GPS) and Galactic Cluster Survey (GCS). U2HS will achieve a 5-σ point source sensitivity of K~18.4 mag (Vega), over three magnitudes deeper than the Two Micron All Sky Survey (2MASS). In this contribution we discuss survey design, execution, data acquisition and processing, photometric calibration and quality control. The data obtained by the U2HS will be made publicly available through the Wide Field Science Archive (WSA) maintained by the WFAU.

Y2K for Librarians: Exactly What You Need To Do.

ERIC Educational Resources Information Center

Doering, William

1999-01-01

Addresses how libraries can prepare for Y2K problems. Discusses technology that might be affected and equipment that should be examined, difficulty of fixing noncompliant hardware and software, identifying problem areas and developing solutions, and dealing with vendors. Includes a checklist of necessary preparations. (AEF)

Insulating and metallic spin glass in Ni-doped K x Fe 2 - y Se 2 single crystals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ryu, Hyejin; Abeykoon, Milinda; Wang, Kefeng

2015-05-01

Here in this paper, we report electron doping effects by Ni in K xFe 2- δ-y Ni ySe 2 (0.06 ≤ y ≤ 1.44) single-crystal alloys. A rich ground-state phase diagram is observed. A small amount of Ni (~4 %) suppressed superconductivity below 1.8 K, inducing insulating spin-glass magnetic ground state for higher Ni content. With further Ni substitution, metallic resistivity is restored. For high Ni concentration in the lattice the unit cell symmetry is high symmetry I4/mmm with no phase separation whereas both I4 / m + I4/mmm space groups were detected in the phase separated crystals when concentrationmore » of Ni< Fe. The absence of superconductivity coincides with the absence of crystalline Fe vacancy order.« less

5S ribosomal RNA database Y2K

PubMed Central

Szymanski, Maciej; Barciszewska, Miroslawa Z.; Barciszewski, Jan; Erdmann, Volker A.

2000-01-01

This paper presents the updated version (Y2K) of the database of ribosomal 5S ribonucleic acids (5S rRNA) and their genes (5S rDNA), http://rose.man/poznan. pl/5SData/index.html . This edition of the database contains 1985 primary structures of 5S rRNA and 5S rDNA. They include 60 archaebacterial, 470 eubacterial, 63 plastid, nine mitochondrial and 1383 eukaryotic sequences. The nucleotide sequences of the 5S rRNAs or 5S rDNAs are divided according to the taxonomic position of the source organisms. PMID:10592212

5S ribosomal RNA database Y2K.

PubMed

Szymanski, M; Barciszewska, M Z; Barciszewski, J; Erdmann, V A

2000-01-01

This paper presents the updated version (Y2K) of the database of ribosomal 5S ribonucleic acids (5S rRNA) and their genes (5S rDNA), http://rose.man/poznan.pl/5SData/index.html. This edition of the database contains 1985primary structures of 5S rRNA and 5S rDNA. They include 60 archaebacterial, 470 eubacterial, 63 plastid, nine mitochondrial and 1383 eukaryotic sequences. The nucleotide sequences of the 5S rRNAs or 5S rDNAs are divided according to the taxonomic position of the source organisms.

NASA Year 2000 (Y2K) Program Plan

NASA Technical Reports Server (NTRS)

1998-01-01

NASA initiated the Year 2000 (Y2K) program in August 1996 to address the challenges imposed on Agency software, hardware, and firmware systems by the new millennium. The Agency program is centrally managed by the NASA Chief Information Officer, with decentralized execution of program requirements at each of the nine NASA Centers, Headquarters and the Jet Propulsion Laboratory. The purpose of this Program Plan is to establish Program objectives and performance goals; identify Program requirements; describe the management structure; and detail Program resources, schedules, and controls. Project plans are established for each NASA Center, Headquarters, and the Jet Propulsion Laboratory.

The VIRMOS deep imaging survey. I. Overview, survey strategy, and CFH12K observations

NASA Astrophysics Data System (ADS)

Le Fèvre, O.; Mellier, Y.; McCracken, H. J.; Foucaud, S.; Gwyn, S.; Radovich, M.; Dantel-Fort, M.; Bertin, E.; Moreau, C.; Cuillandre, J.-C.; Pierre, M.; Le Brun, V.; Mazure, A.; Tresse, L.

2004-04-01

This paper describes the CFH12K-VIRMOS survey: a deep BVRI imaging survey in four fields totalling more than 17 deg2, conducted with the 40×30 arcmin2 field CFH-12K camera. The survey is intended to be a multi-purpose survey used for a variety of science goals, including surveys of very high redshift galaxies and weak lensing studies. Four high galactic latitude fields, each 2×2 deg2, have been selected along the celestial equator: 0226-04, 1003+01, 1400+05, and 2217+00. The 16 deg2 of the ``wide'' survey are covered with exposure times of 2 hr, 1.5 hr, 1 hr, 1 hr, respectively while the 1.3×1 deg2 area of the ``deep'' survey at the center of the 0226-04 field is covered with exposure times of 7 h, 4.5 h, 3 h, 3 h, in BVRI respectively. An additional area ˜2 deg2 has been imaged in the 0226-04 field corresponding to the area surveyed by the XMM-LSS program \\citep{pierre03}. The data is pipeline processed at the Terapix facility at the Institut d'Astrophysique de Paris to produce large mosaic images. The catalogs produced contain the positions, shapes, total and aperture magnitudes for 2.175 million objects measured in the four areas. The limiting magnitudes, measured as a 5σ measurement in a 3 arcsec diameter aperture is IAB=24.8 in the ``Wide'' areas, and IAB=25.3 in the deep area. Careful quality control has been applied on the data to ensure internal consistency and assess the photometric and astrometric accuracy as described in a joint paper \\citep{mccracken03}. These catalogs are used to select targets for the VIRMOS-VLT Deep Survey, a large spectroscopic survey of the distant universe (Le Fèvre et al. 2003). First results from the CFH12K-VIRMOS survey have been published on weak lensing (e.g. van Waerbeke & Mellier 2003). Catalogs and images are available through the VIRMOS database environment under Oracle (http://www.oamp.fr/cencos). They are open for general use since July 1st, 2003. Appendix A is only available in electronic form at http://www.edpsciences.org

17 CFR 249.618 - Form BD-Y2K, information required of broker-dealers pursuant to section 17 of the Securities...

Code of Federal Regulations, 2010 CFR

2010-04-01

... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Form BD-Y2K, information... Exchange Members, Brokers, and Dealers § 249.618 Form BD-Y2K, information required of broker-dealers... FR 37674, July 13, 1998] Editorial Note: For Federal Register citations affecting Form BD-Y2K, see...

The Y2K problem and management strategies for the individual practitioner.

PubMed

Alex, J C; Jassin, B M

1999-01-01

This article will detail concisely the nature of the Y2K problem, how it could affect your computer systems and your business, and what measures you can institute to minimize and/or eliminate computer failure as you enter the year 2000.

17 CFR 249.619 - Form TA-Y2K, information required of transfer agents pursuant to section 17 of the Securities...

Code of Federal Regulations, 2010 CFR

2010-04-01

... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Form TA-Y2K, information... Certain Exchange Members, Brokers, and Dealers § 249.619 Form TA-Y2K, information required of transfer... affecting Form TA-Y2K, see the List of CFR Sections Affected, which appears in the Finding Aids section of...

Isolation of (CO)1- and (CO2)1- radical complexes of rare earths via Ln(NR2)3/K reduction and [K2(18-crown-6)2]2+ oligomerization.

PubMed

Fang, Ming; Farnaby, Joy H; Ziller, Joseph W; Bates, Jefferson E; Furche, Filipp; Evans, William J

2012-04-11

Deep-blue solutions of Y(2+) formed from Y(NR(2))(3) (R = SiMe(3)) and excess potassium in the presence of 18-crown-6 at -45 °C under vacuum in diethyl ether react with CO at -78 °C to form colorless crystals of the (CO)(1-) radical complex, {[(R(2)N)(3)Y(μ-CO)(2)][K(2)(18-crown-6)(2)]}(n), 1. The polymeric structure contains trigonal bipyramidal [(R(2)N)(3)Y(μ-CO)(2)](2-) units with axial (CO)(1-) ligands linked by [K(2)(18-crown-6)(2)](2+) dications. Byproducts such as the ynediolate, [(R(2)N)(3)Y](2)(μ-OC≡CO){[K(18-crown-6)](2)(18-crown-6)}, 2, in which two (CO)(1-) anions are coupled to form (OC≡CO)(2-), and the insertion/rearrangement product, {(R(2)N)(2)Y[OC(═CH(2))Si(Me(2))NSiMe(3)]}[K(18-crown-6)], 3, are common in these reactions that give variable results depending on the specific reaction conditions. The CO reduction in the presence of THF forms a solvated variant of 2, the ynediolate [(R(2)N)(3)Y](2)(μ-OC≡CO)[K(18-crown-6)(THF)(2)](2), 2a. CO(2) reacts analogously with Y(2+) to form the (CO(2))(1-) radical complex, {[(R(2)N)(3)Y(μ-CO(2))(2)][K(2)(18-crown-6)(2)]}(n), 4, that has a structure similar to that of 1. Analogous (CO)(1-) and (OC≡CO)(2-) complexes of lutetium were isolated using Lu(NR(2))(3)/K/18-crown-6: {[(R(2)N)(3)Lu(μ-CO)(2)][K(2)(18-crown-6)(2)]}(n), 5, [(R(2)N)(3)Lu](2)(μ-OC≡CO){[K(18-crown-6)](2)(18-crown-6)}, 6, and [(R(2)N)(3)Lu](2)(μ-OC≡CO)[K(18-crown-6)(Et(2)O)(2)](2), 6a. © 2012 American Chemical Society

New Y2K problem for mask making (or, Surviving mask data problems after 2000)

NASA Astrophysics Data System (ADS)

Sturgeon, Roger

1999-08-01

The Y2K problem has analogies in the mask-making world. With the Y2K problem where a date field has just two bytes for the year, there are some cases of mask-making data in which the file size cannot exceed 2 gigabytes. Where a two-digit date field can only unambiguously use a limited range of values (00 to 99), design coordinates can only cover a range of about 4 billion values, which is getting a little uncomfortable for all of the new applications. In retrospect, with a degree of foresight and planning the Y2K date problem could have been easily solved if new encodings had been allowed in the two- digit field. Likewise, in the mask-making industry we currently have the opportunity to achieve far superior data compression if we allow some new forms of data encoding in our data. But this will require universal agreement. The correct way to look at the Y2K problem is that some information was left out of the data stream due to common understandings that made the additional information superfluous. But as the year 2000 approaches, it has become widely recognized that missing data needs to be stated explicitly, and any ambiguities in the representation of the data will need to be eliminated with precise specifications. In a similar way, old mask data generation methods have had numerous flaws that we have been able to ignore for a long time. But now is the time to fix theses flaws and provide extended capabilities. What is not yet clear is if the old data generation methods can be modified to meet these developing needs. Unilateral action is not likely to lead to much progress, so some united effort is required by all interested parties if success is to be achieved in the brief time that remains.

Thermodynamic Assessment of the Y2o3-yb2o3-zro2 System

NASA Technical Reports Server (NTRS)

Jacobson, Nathan S.; Liu, Zi-Kui; Kaufman, Larry; Zhang, Fan

2002-01-01

Yttria-zirconia (Y2O3-ZrO2) is the most widely used of the rare earth oxide-zirconia systems. There are numerous experimental studies of the phase boundaries in this system. In this paper, we assess these data and derive parameters for the solution models in this system. There is current interest in other rare earth oxide-zirconia systems as well as systems with several rare earth oxides and zirconia, which may offer improved properties over the Y2O3-ZrO2 system. For this reason, we also assess the ytterbia-zirconia (Yb2O3-ZrO2) and Y2O3-Yb2O3-ZrO2 system.

K-KIDS: K Dwarfs and Their Companions. First Results from Radial Velocity Survey with CHIRON Spectrograph

NASA Astrophysics Data System (ADS)

Paredes, Leonardo; Henry, Todd; Nusdeo, Daniel; Winters, J.; Dincer, Tolga

2018-01-01

We present the K-KIDS project, an effort to survey a large sample of K dwarfs and their companions, the KIDS. We are observing a carefully vetted equatorial sample (DEC = -30 to +30) of more than 1000 K dwarfs within 50 pc to make a comprehensive assessment of stellar, substellar and planetary companions with separations of 0.1 to 10,000 AU.The initial sample of 1048 stars has been compiled using astrometric data from Hipparcos and photometric data from Tycho-2 and 2MASS. Four different imaging and spectroscopic surveys are underway. Here we present the strategy and initial results for our high-precision radial velocity survey for the closest companions using the CHIRON spectrograph on the CTIO/SMARTS 1.5m telescope. Individual measurements with CHIRON at R = 80,000 using ThAr wavelength calibration, indicate that for K dwarf radial velocity standards with V = 5.8, 7.0 and 8.0 yield precisions over 6 weeks of observing of 7.4 m/s, 9.8 m/s and 5.7 m/s. In the first two months, a core sample of 42 K dwarfs, including carefully selected calibration systems as well as previously unobserved stars, was observed every few nights to detect the radial velocity signals of close companions. In our calibration stellar systems, we have confirmed the suitability of CHIRON for our studies, by having found periodic radial velocity perturbations consistent with hot Jupiter and stellar companions previously detected. This set forms the foundation of our one-year survey of 100 K dwarfs with magnitudes as faint as V = 11.5, for which we should detect companions with masses as low as Jupiter.In light of the promising performance and efficiency of the CHIRON spectrograph for a long-term radial velocity survey, we have expanded our initial sample using Gaia Data Release 1 to 1824 K dwarfs within 50 pc. Ultimately, the combination of all four surveys will provide an unprecedented portrait of K dwarfs and their kids.This effort has been supported by the NSF through grant AST-1517413, and

Prostaglandins in the kidney: developments since Y2K.

PubMed

Nasrallah, Rania; Clark, Jordan; Hébert, Richard L

2007-10-01

There are five major PGs (prostaglandins/prostanoids) produced from arachidonic acid via the COX (cyclo-oxygenase) pathway: PGE(2), PGI(2) (prostacyclin), PGD(2), PGF(2alpha) and TXA(2) (thromboxane A(2)). They exert many biological effects through specific G-protein-coupled membrane receptors, namely EP (PGE(2) receptor), IP (PGI(2) receptor), DP (PGD(2) receptor), FP (PGF(2alpha) receptor) and TP (TXA(2) receptor) respectively. PGs are implicated in physiological and pathological processes in all major organ systems, including cardiovascular function, gastrointestinal responses, reproductive processes, renal effects etc. This review highlights recent insights into the role of each prostanoid in regulating various aspects of renal function, including haemodynamics, renin secretion, growth responses, tubular transport processes and cell fate. A thorough review of the literature since Y2K (year 2000) is provided, with a general overview of PGs and their synthesis enzymes, and then specific considerations of each PG/prostanoid receptor system in the kidney.

Cost of privacy rules could dwarf Y2K, experts say.

PubMed

2000-03-01

It may not have generated the media hype that the Y2K computer bug did, but the Health Insurance Portability and Accountability Act could end up costing hospitals several times as much. The brunt of the expense is likely to come from the law's privacy standards, which experts say are so broad and complex that simply understanding which parts apply to your facility could represent a major undertaking.

Effects of Co and Mn doping in K0.8Fe2-ySe2 revisited.

PubMed

Zhou, Tingting; Chen, Xiaolong; Guo, Jiangang; Jin, Shifeng; Wang, Gang; Lai, Xiaofang; Ying, Tianping; Zhang, Han; Shen, Shijie; Wang, Shunchong; Zhu, Kaixing

2013-07-10

Accumulated evidence indicates that phase separation occurs in potassium intercalated iron selenides, a superconducting phase coexisting with the antiferromagnetic phase K2Fe4Se5, the so-called '245 phase'. Here, we report a comparative study of substitution effects by Co and Mn for Fe sites in K0.8Fe2-ySe2 within the phase separation scenario. Our results demonstrate that Co and Mn dopants have distinct differences in occupancy and hence in the suppression mechanism of superconductivity upon doping of Fe sites. In K0.8Fe2-xCoxSe2, Co prefers to occupy the lattice of the superconducting phase and suppresses superconductivity very quickly, obeying the magnetic pair-breaking mechanism or the collapse of the Fermi surface nesting mechanism. In contrast, in K0.8Fe1.7-xMnxSe2, Mn shows no preferential occupancy in the superconducting phase or the 245 phase. The suppression of superconductivity can be attributed to restraining of the superconducting phase and meanwhile inducing another non-superconducting phase by Mn doping.

Sustained phase separation and spin glass in Co-doped K x Fe 2 - y Se 2 single crystals

DOE PAGES

Ryu, Hyejin; Wang, Kefeng; Opacic, M.; ...

2015-11-19

We describe Co substitution effects in K xFe 2-y-zCo zSe 2 (0.06 ≤ z ≤ 1.73) single crystal alloys. By 3.5% of Co doping superconductivity is suppressed whereas phase separation of semiconducting K 2Fe 4Se 5 and superconducting/metallic K xFe 2Se 2 is still present. We show that the arrangement and distribution of superconducting phase (stripe phase) is connected with the arrangement of K, Fe and Co atoms. Semiconducting spin glass is found in proximity to superconducting state, persisting for large Co concentrations. At high Co concentrations ferromagnetic metallic state emerges above the spin glass. This is coincident withmore » changes of the unit cell, arrangement and connectivity of stripe conducting phase.« less

The Kepler and K2 Near-Infrared Transit Survey (KNITS)

NASA Astrophysics Data System (ADS)

Colon, Knicole; Rodriguez, Joseph E.; Barentsen, Geert; Cardoso, Jose Vinicius de Miranda; Vanderburg, Andrew

2018-01-01

NASA's Kepler mission discovered a plethora of transiting exoplanets after observing a single region of the Galaxy for four years. After a second reaction wheel failed, NASA's Kepler spacecraft was repurposed as K2 to observe different fields along the ecliptic in ~80 day campaigns. To date, K2 has discovered ~130 exoplanets along with another ~400 candidates. The exoplanets that have been confirmed or validated from Kepler and K2 have been primarily subject to spectroscopic observations, high-resolution imaging, or statistical methods. However, most of these, along with all the remaining candidate exoplanets, have had no follow-up transit photometry. In addition, recent studies have shown that for single-planet systems, statistical validation alone can be unreliable and additional follow-up observations are required to reveal the true nature of the system. I will present the latest results from an ongoing program to use the 3.5-meter WIYN telescope at Kitt Peak National Observatory for near-infrared transit photometry of Kepler and K2 exoplanets and candidates. Our program of high-precision, high-cadence, high-spatial-resolution near-infrared transit photometry is providing new measurements of the transit ephemerides and planetary radii as well as weeding out false positives lurking within the candidate lists. To date, 25 K2 and 5 Kepler targets have been observed with WIYN. I will also describe upcoming observations with WIYN that will take place in January 2018 as part of a campaign to observe exoplanet transits in the near-infrared simultaneously with the Kepler spacecraft during K2 Campaign 16. Our program ultimately provides a vetted sample of exoplanets that could be targeted in the future by NASA’s James Webb Space Telescope (JWST) and also demonstrates WIYN’s capabilities for observations of exoplanets to be discovered by NASA's all-sky Transiting Exoplanet Survey Satellite (TESS).Data presented herein were obtained at the WIYN Observatory from

Optimization of single crystals of solid electrolytes with tysonite-type structure (LaF3) for conductivity at 293 K: 2. Nonstoichiometric phases R 1- y M y F3- y ( R = La-Lu, Y; M = Sr, Ba)

NASA Astrophysics Data System (ADS)

Sorokin, N. I.; Sobolev, B. P.; Krivandina, E. A.; Zhmurova, Z. I.

2015-01-01

Single crystals of fluorine-conducting solid electrolytes R 1 - y Sr y F3 - y and R 1 - y Ba y F3 - y ( R = La-Lu, Y) with a tysonite-type structure (LaF3) have been optimized for room-temperature conductivity σ293 K. The optimization is based on high-temperature measurements of σ( T) in two-component nonstoichiometric phases R 1 - y M y F3 - y ( M = Sr, Ba) as a function of the MF2 content. Optimization for thermal stability is based on studying the phase diagrams of MF2- RF3 systems ( M = Sr, Ba) and the behavior of nonstoichiometric crystals upon heating when measuring temperature dependences σ( T). Single crystals of many studied R 1 - y Sr y F3 - y and R 1 - y Ba y F3 - y phases have σ293 K values large enough to use these materials in solid-state electrochemical devices (chemical sensors, fluorine-ion batteries, accumulators, etc.) operating at room temperature.

A Multi-resolution, Multi-epoch Low Radio Frequency Survey of the Kepler K2 Mission Campaign 1 Field

NASA Astrophysics Data System (ADS)

Tingay, S. J.; Hancock, P. J.; Wayth, R. B.; Intema, H.; Jagannathan, P.; Mooley, K.

2016-10-01

We present the first dedicated radio continuum survey of a Kepler K2 mission field, Field 1, covering the North Galactic Cap. The survey is wide field, contemporaneous, multi-epoch, and multi-resolution in nature and was conducted at low radio frequencies between 140 and 200 MHz. The multi-epoch and ultra wide field (but relatively low resolution) part of the survey was provided by 15 nights of observation using the Murchison Widefield Array (MWA) over a period of approximately a month, contemporaneous with K2 observations of the field. The multi-resolution aspect of the survey was provided by the low resolution (4‧) MWA imaging, complemented by non-contemporaneous but much higher resolution (20″) observations using the Giant Metrewave Radio Telescope (GMRT). The survey is, therefore, sensitive to the details of radio structures across a wide range of angular scales. Consistent with other recent low radio frequency surveys, no significant radio transients or variables were detected in the survey. The resulting source catalogs consist of 1085 and 1468 detections in the two MWA observation bands (centered at 154 and 185 MHz, respectively) and 7445 detections in the GMRT observation band (centered at 148 MHz), over 314 square degrees. The survey is presented as a significant resource for multi-wavelength investigations of the more than 21,000 target objects in the K2 field. We briefly examine our survey data against K2 target lists for dwarf star types (stellar types M and L) that have been known to produce radio flares.

A new use of K-Y jelly as a gonioscopy fluid.

PubMed Central

Mehta, H. K.

1984-01-01

Methylcellulose drops varying in strength between 0.3% and 2.0% and isotonic saline are the fluids currently used for gonioscopy and posterior segment examination of the eye with diagnostic contact lenses. The author reports the use of K-Y jelly for such examinations in over 80 patients after having it used on his own eyes without any immediate or delayed ill effects. No observable difference was found between saline drops, methylcellulose drops of 0.3% and 2.0%, and K-Y jelly as regards the visibility of the anterior and posterior segments of the eyes. The more viscous fluids of 2% methylcellulose and K-Y jelly were more convenient to use, as they rarely allowed interposition of air bubbles between the cornea and the contact lens. K-Y jelly was well tolerated by all subjects. PMID:6477858

The Y2K Problem: Will It Just Be Another New Year's Eve?

ERIC Educational Resources Information Center

Iwanowski, Jay

1998-01-01

Potential problems for college and university computing functions posed by arrival of the year 2000 (Y2K) are discussed, including arithmetic calculations and sorting functions based on two-digit year dates, embedding of two-digit dates in archival data, system coordination for data exchange, unique number generation, and leap year calculations. A…

Colleges' Effort To Prepare for Y2K May Yield Benefits for Many Years.

ERIC Educational Resources Information Center

Olsen, Florence

2000-01-01

Suggests that the money spent ($100 billion) to fix the Y2K bug in the United States resulted in improved campus computer systems. Reports from campuses around the country indicate that both mainframe and desktop systems experienced fewer problems than expected. (DB)

Characterization of P2Y receptors mediating ATP induced relaxation in guinea pig airway smooth muscle: involvement of prostaglandins and K+ channels.

PubMed

Montaño, Luis M; Cruz-Valderrama, José E; Figueroa, Alejandra; Flores-Soto, Edgar; García-Hernández, Luz M; Carbajal, Verónica; Segura, Patricia; Méndez, Carmen; Díaz, Verónica; Barajas-López, Carlos

2011-10-01

In airway smooth muscle (ASM), adenosine 5'-triphosphate (ATP) induces a relaxation associated with prostaglandin production. We explored the role of K(+) currents (I (K)) in this relaxation. ATP relaxed the ASM, and this effect was abolished by indomethacin. Removal of airway epithelium slightly diminished the ATP-induced relaxation at lower concentration without modifying the responses to ATP at higher concentrations. ATPγS and UTP induced a concentration-dependent relaxation similar to ATP; α,β-methylene-ATP was inactive from 1 to 100 μM. Suramin or reactive blue 2 (RB2), P2Y receptor antagonists, did not modify the relaxation, but their combination significantly reduced this effect of ATP. The relaxation was also inhibited by N-ethylmaleimide (NEM; which uncouples G proteins). In myocytes, the ATP-induced I (K) increment was not modified by suramin or RB2 but the combination of both drugs abolished it. This increment in the I (K) was also completely nullified by NEM and SQ 22,536. 4-Amynopyridine or iberiotoxin diminished the ATP-induced I (K) increment, and the combination of both substances diminished ATP-induced relaxation. The presence of P2Y(2) and P2Y(4) receptors in smooth muscle was corroborated by Western blot and confocal images. In conclusion, ATP: (1) produces relaxation by inducing the production of bronchodilator prostaglandins in airway smooth muscle, most likely by acting on P2Y(4) and P2Y(2) receptors; (2) induces I (K) increment through activation of the delayed rectifier K(+) channels and the high-conductance Ca(2+)-dependent K(+) channels, therefore both channels are implicated in the ATP-induced relaxation; and (3) this I (K) increment is mediated by prostaglandin production which in turns increase cAMP signaling pathway.

The power spectrum of galaxies in the 2dF 100k redshift survey

NASA Astrophysics Data System (ADS)

Tegmark, Max; Hamilton, Andrew J. S.; Xu, Yongzhong

2002-10-01

We compute the real-space power spectrum and the redshift-space distortions of galaxies in the 2dF 100k galaxy redshift survey using pseudo-Karhunen-Loève eigenmodes and the stochastic bias formalism. Our results agree well with those published by the 2dFGRS team, and have the added advantage of producing easy-to-interpret uncorrelated minimum-variance measurements of the galaxy-galaxy, galaxy-velocity and velocity-velocity power spectra in 27 k-bands, with narrow and well-behaved window functions in the range 0.01 h Mpc-1 < k < 0.8 h Mpc-1. We find no significant detection of baryonic wiggles, although our results are consistent with a standard flat ΩΛ= 0.7`concordance' model and previous tantalizing hints of baryonic oscillations. We measure the galaxy-matter correlation coefficient r > 0.4 and the redshift-distortion parameter β= 0.49 +/- 0.16 for r= 1 (β= 0.47 +/- 0.16 without finger-of-god compression). Since this is an apparent-magnitude limited sample, luminosity-dependent bias may cause a slight red-tilt in the power spectrum. A battery of systematic error tests indicate that the survey is not only impressive in size, but also unusually clean, free of systematic errors at the level to which our tests are sensitive. Our measurements and window functions are available at http://www.hep.upenn.edu/~max/2df.html together with the survey mask, radial selection function and uniform subsample of the survey that we have constructed.

Assessment of solid/liquid equilibria in the (U, Zr)O2+y system

NASA Astrophysics Data System (ADS)

Mastromarino, S.; Seibert, A.; Hashem, E.; Ciccioli, A.; Prieur, D.; Scheinost, A.; Stohr, S.; Lajarge, P.; Boshoven, J.; Robba, D.; Ernstberger, M.; Bottomley, D.; Manara, D.

2017-10-01

Solid/liquid equilibria in the system UO2sbnd ZrO2 are revisited in this work by laser heating coupled with fast optical thermometry. Phase transition points newly measured under inert gas are in fair agreement with the early measurements performed by Wisnyi et al., in 1957, the only study available in the literature on the whole pseudo-binary system. In addition, a minimum melting point is identified here for compositions near (U0.6Zr0.4)O2+y, around 2800 K. The solidus line is rather flat on a broad range of compositions around the minimum. It increases for compositions closer to the pure end members, up to the melting point of pure UO2 (3130 K) on one side and pure ZrO2 (2970 K) on the other. Solid state phase transitions (cubic-tetragonal-monoclinic) have also been observed in the ZrO2-rich compositions X-ray diffraction. Investigations under 0.3 MPa air (0.063 MPa O2) revealed a significant decrease in the melting points down to 2500 K-2600 K for increasing uranium content (x(UO2)> 0.2). This was found to be related to further oxidation of uranium dioxide, confirmed by X-ray absorption spectroscopy. For example, a typical oxidised corium composition U0.6Zr0.4O2.13 was observed to solidify at a temperature as low as 2493 K. The current results are important for assessing the thermal stability of the system fuel - cladding in an oxide based nuclear reactor, and for simulating the system behaviour during a hypothetical severe accident.

A new set of K3Fe3(PO4)4·yH2O (0 ≤ y ≤ 1) layered phases obtained by topotactic reactions

NASA Astrophysics Data System (ADS)

Trad, Khiem; Wattiaux, Alain; Ben Amara, Mongi; Delmas, Claude; Carlier, Dany

2018-06-01

K3Fe3(PO4)4·H2O powder was synthesized by Na+/K+ exchange reaction from Na3Fe3(PO4)4 in aqueous medium. The replacement of the sodium cations by the potassium larger ones and water molecules causes a structural distortion leading to P2/n monoclinic K3Fe3(PO4)4·H2O. This new layered phase was characterized by XRD, Mössbauer spectroscopy and magnetic measurements. The study of its thermal stability reveals that other new layered K3Fe3(PO4)4·yH2O with (0 ≤ y ≤ 1) phases can be stabilized up to 600 °C and finally at higher temperature a new K3Fe3(PO4)4 polymorph with a different structural type is irreversibility formed.

Thermoluminescence and glow curves analysis of γ-exposed Eu{sup 3+} doped K{sub 3}Y(PO{sub 4}){sub 2} nanophosphors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gupta, Palvi; Bedyal, A.K.; Kumar, Vinay, E-mail: vinaykdhiman@yahoo.com

2016-01-15

Highlights: • First time, a detailed comparative study of the glow curves and kinetic parameters was made on K{sub 3}Y(PO{sub 4}){sub 2} nanophosphor. • Combustion method was employed to synthesize the Eu{sup 3+} doped K{sub 3}Y(PO{sub 4}){sub 2} nanophosphor. • The nanophosphor exhibited sublinear response suggesting that it is suitable for TL dosimetry. - Abstract: Eu{sup 3+} doped K{sub 3}Y(PO{sub 4}){sub 2} nanophosphor was synthesized by combustion synthesis using urea as a fuel. The crystal structure and particle morphology of the nanophosphor were investigated by using X-ray diffraction and transmission electron microscopy, respectively. A Thermoluminescence (TL) study was carried outmore » after exposing the samples to gamma radiation. The TL glow curves exhibited a prominent peak at 407 K and a small hump at 478 K. The intensity of the peaks increased with the increase in the dose of the gamma rays (0.01–5 kGy). The K{sub 3}Y(PO{sub 4}){sub 2}: Eu{sup 3+} (2.5 mol%) nanophosphor exhibited sublinear TL response to γ-radiation over a wide range of gamma doses (0.01–5 kGy). The TLanal program was used to analyze the glow curves of the K{sub 3}Y(PO{sub 4}){sub 2} nanophosphor at different doses (0.2–5 kGy) and different heating rates (3–10 K/s). A comparative study was done for kinetic trapping parameters that were determined by the peak shape methods of Chen, Grossweiner and Lushchik. The frequency factors (s) for each glow peak were also calculated. The values of the activation energy (E) obtained by the TLanal program were in good agreement with those obtained by the peak shape methods. The effect of different amount of doses and different heating rates are discussed.« less

Characterization of a novel Y2K-type dehydrin VrDhn1 from Vigna radiata.

PubMed

Lin, Chia-Hui; Peng, Po-Hsin; Ko, Chia-Yun; Markhart, Albert H; Lin, Tsai-Yun

2012-05-01

A novel dehydrin gene (VrDhn1) was isolated from an embryo cDNA library of Vigna radiata (L.) Wilczek (mungbean) variety VC1973A. The intronless VrDhn1 gene encodes a protein belonging to the Y(2)K-type dehydrin family. VrDhn1 protein accumulated in embryos and cotyledons during seed maturation and disappeared 2 days after seed imbibition (DAI). The expression of VrDhn1 mRNA and accumulation of VrDhn1 protein were at high levels in mature seeds, but neither mRNA nor protein was detected in mungbean vegetative tissues under normal growth conditions. The VrDhn1 mRNA level was extremely high in mature seeds and decreased to ∼30% at 1 DAI, and was not detectable at ~7 DAI. Tissue dehydration, salinity and exogenous ABA markedly induced VrDhn1 transcripts in plants as measured by quantitative real-time reverse transcription-PCR (qRT-PCR). VrDhn1 protein was not detected using immunoblots in seedlings under stress treatments. In mature seeds or 1 DAI seedlings, VrDhn1 proteins were immunolocalized in the nucleus and cytoplasm. VrDhn1 exhibited low affinity for non-specific interaction with DNA using electrophoretic mobility shift assays (EMSAs), and the exogenous addition of Zn(2+) or Ni(2+) stimulated interaction. The His-tagged VrDhn1 (30.17 kDa) protein showed a molecular mass of 63.1 kDa on gel filtration, suggesting a dimer form. This is the first report showing that a Y(2)K-type VrDhn1 enters the nucleus and interacts with DNA during seed maturation.

Consequence assessment for Airborne Releases of SO{sub 2} from the Y-12 Pilot Dechlorination Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pendergrass, W.R.

The Atmospheric Turbulence and Diffusion Division was requested by the Department of Energy`s Oak Ridge Operations Office to conduct a consequence assessment for potential atmospheric releases of SO{sub 2} from the Y-12 Pilot Dechlorination Facility. The focus of the assessment was to identify ``worst`` case meteorology which posed the highest concentration exposure potential for both on-site as well as off-site populations. A series of plausible SO{sub 2} release scenarios were provided by Y-12 for the consequence assessment. Each scenario was evaluated for predictions of downwind concentration, estimates of a five-minute time weighted average, and estimate of the dimension of themore » puff. The highest hazard potential was associated with Scenario 1, in which a total of eight SO{sub 2} cylinders are released internally to the Pilot Facility and exhausted through the emergency venting system. A companion effort was also conducted to evaluate the potential for impact of releases of SO{sub 2} from the Pilot Facility on the population of Oak Ridge. While specific transport trajectory data is not available for the Pilot Facility, extrapolations based on the Oak Ridge Site Survey and climatological records from the Y-12 meteorological program does not indicate the potential for impact on the city of Oak Ridge. Steering by the local topographical features severely limits the potential impact ares. Due to the lack of specific observational data, both tracer and meteorological, only inferences can be made concerning impact zones. It is recommended tat the Department of Energy Oak Ridge Operations examine the potential for off-site impact and develop the background data to prepare impact zones for releases of hazardous materials from the Y-12 facility.« less

Case study: physicians develop results viewer amid Y2K commotion.

PubMed

Wurz, J A; Manis, J L

2000-01-01

Amid a flurry of Y2K preparations, which included converting patient accounting and order processing systems for six of its eight hospitals, Advocate Health Care needed to address physician complaints that the compliant software was awkward. By partnering with physicians, information systems (IS) rapidly developed a solution that met both the need for compliance and the demand for an easy-to-use, patient-centric clinical information system. A robust, browser-based results viewer provides physician access to information from patient accounting, order processing, and several clinical ancillary systems. Advocate anticipates greater challenges as the system is promoted to other sites and clinical communities.

Year 2000 (Y2K) computer compliance guide; guidance for FDA personnel. Food and Drug Administration. Notice.

PubMed

1999-05-14

The Food and Drug Administration (FDA) is announcing the availability of a new compliance policy guide (CPG) entitled "Year 2000 (Y2K) Computer Compliance" (section 160-800). This guidance document represents the agency's current thinking on the manufacturing and distribution of domestic and imported products regulated by FDA using computer systems that may not perform properly before, or during, the transition to the year 2000 (Y2K). The text of the CPG is included in this notice. This compliance guidance document is an update to the Compliance Policy Guides Manual (August 1996 edition). It is a new CPG, and it will be included in the next printing of the Compliance Policy Guides Manual. This CPG is intended for FDA personnel, and it is available electronically to the public.

Modulation of K+ currents in Xenopus spinal neurons by p2y receptors: a role for ATP and ADP in motor pattern generation

PubMed Central

Brown, Paul; Dale, Nicholas

2002-01-01

We have investigated the pharmacological properties and targets of p2y purinoceptors in Xenopus embryo spinal neurons. ATP reversibly inhibited the voltage-gated K+ currents by 10 ± 3 %. UTP and the analogues α,β-methylene-ATP and 2-methylthio-ATP also inhibited K+ currents. This agonist profile is similar to that reported for a p2y receptor cloned from Xenopus embryos. Voltage-gated K+ currents could be inhibited by ADP (9 ± 0.8 %) suggesting that a further p2y1-like receptor is also present in the embryo spinal cord. Unexpectedly we found that α,β-methylene-ADP, often used to block the ecto-5′-nucleotidase, also inhibited voltage-gated K+ currents (7 ± 2.3 %). This inhibition was occluded by ADP, suggesting that α,β-methylene-ADP is an agonist at p2y1 receptors. We have directly studied the properties of the ecto-5′-nucleotidase in Xenopus embryo spinal cord. Although ADP inhibited this enzyme, α,β-methylene-ADP had no action. Caution therefore needs to be used when interpreting the actions of α,β-methylene-ADP as it has previously unreported agonist activity at P2 receptors. Xenopus spinal neurons possess fast and slow voltage-gated K+ currents. By using catechol to selectively block the fast current, we completely occluded the actions of ATP and ADP. Furthermore, the purines appeared to block only the fast relaxation component of the tail currents. We therefore conclude that the p2y receptors target only the fast component of the delayed rectifier. As ATP breakdown to ADP is rapid and ADP may accumulate at higher levels than ATP, the contribution of ADP acting through p2y1-like receptors may be an important additional mechanism for the control of spinal motor pattern generation. PMID:11986373

Lifelong Learning as a Chameleonic Concept and Versatile Practice: Y2K Perspectives and Trends

ERIC Educational Resources Information Center

Grace, Andre P.

2004-01-01

This essay focuses on contemporary lifelong-learning discourse as it was reflected in deliberations during three events held in Australia, Canada and the UK during 2000-01. Through the dialogical lenses of these Y2K events that brought together an array of international participants, it examines lifelong learning as a chameleonic concept and…

HIPAA is larger and more complex than Y2K.

PubMed

Tempesco, J W

2000-07-01

The Health Insurance Portability and Accountability Act of 1996 (HIPAA) is a larger and more complex problem than Y2K ever was. According to the author, the costs associated with a project of such unending scope and in support of intrusion into both information and operational systems of every health care transaction will be incalculable. Some estimate that the administrative simplification policies implemented through HIPAA will save billions of dollars annually, but it remains to be seen whether the savings will outweigh implementation and ongoing expenses associated with systemwide application of the regulations. This article addresses the rules established for electronic data interchange, data set standards for diagnostic and procedure codes, unique identifiers, coordination of benefits, privacy of individual health care information, electronic signatures, and security requirements.

The hybrid lattice of K(x)Fe(2-y)Se2: where superconductivity and magnetism coexist.

PubMed

Louca, Despina; Park, Keeseong; Li, Bing; Neuefeind, Joerg; Yan, Jiaqiang

2013-01-01

Much remains unknown of the microscopic origin of superconductivity in atomically disordered systems of amorphous alloys or in crystals riddled with defects. A manifestation of this conundrum is envisaged in the highly defective superconductor of K(x)Fe(2-y)Se2. How can superconductivity survive under such crude conditions that call for strong electron localization? Here, we show that the Fe sublattice is locally distorted and accommodates two kinds of Fe valence environments giving rise to a bimodal bond-distribution, with short and long Fe bonds. The bimodal bonds are present even as the system becomes superconducting in the presence of antiferromagnetism, with the weight continuously shifting from the short to the long with increasing K content. Such a hybrid state is most likely found in cuprates as well while our results point to the importance of the local atomic symmetry by which exchange interactions between local moments materialize.

Development of a paperless, Y2K compliant exposure tracking database at Los Alamos National Laboratory.

PubMed

Conwell, J L; Creek, K L; Pozzi, A R; Whyte, H M

2001-02-01

The Industrial Hygiene and Safety Group at Los Alamos National Laboratory (LANL) developed a database application known as IH DataView, which manages industrial hygiene monitoring data. IH DataView replaces a LANL legacy system, IHSD, that restricted user access to a single point of data entry needed enhancements that support new operational requirements, and was not Year 2000 (Y2K) compliant. IH DataView features a comprehensive suite of data collection and tracking capabilities. Through the use of Oracle database management and application development tools, the system is Y2K compliant and Web enabled for easy deployment and user access via the Internet. System accessibility is particularly important because LANL operations are spread over 43 square miles, and industrial hygienists (IHs) located across the laboratory will use the system. IH DataView shows promise of being useful in the future because it eliminates these problems. It has a flexible architecture and sophisticated capability to collect, track, and analyze data in easy-to-use form.

The hybrid lattice of K xFe 2-ySe 2: where superconductivity and magnetism coexist

DOE PAGES

Yang, Junjie; Duan, Chunruo; Huang, Qing; ...

2013-01-01

Much remains unknown of the microscopic origin of superconductivity in atomically disordered systems of amorphous alloys or in crystals riddled with defects. A manifestation of this conundrum is envisaged in the highly defective superconductor of K xFe 2-ySe 2. How can superconductivity survive under such crude conditions that call for strong electron localization? Here, we show that the Fe sublattice is locally distorted and accommodates two kinds of Fe valence environments giving rise to a bimodal bond-distribution, with short and long Fe bonds. The bimodal bonds are present even as the system becomes superconducting in the presence of antiferromagnetism, withmore » the weight continuously shifting from the short to the long with increasing K content. Such a hybrid state is most likely found in cuprates as well while our results point to the importance of the local atomic symmetry by which exchange interactions between local moments materialize.« less

ART: Surveying the Local Universe at 2-11 keV

NASA Technical Reports Server (NTRS)

O'Dell, S. L.; Ramsey, B. D.; Adams, M. L.; Brandt, W. N.; Bubarev, M. V.; Hassinger, G.; Pravlinski, M.; Predehl, P.; Romaine, S. E.; Swartz, D. A.;

K-KIDS: The Imaging Survey for Stellar Companions at Solar System Scales Around More than 1000 K Dwarfs

NASA Astrophysics Data System (ADS)

Nusdeo, Daniel A.

2018-01-01

An initial sample of 1048 K dwarfs, hereafter known as the “K-KIDS” targets, was built from the Hipparcos and 2MASS catalogs in order to construct a robust list for a multiplicity survey. There have been two recent comprehensive stellar multiplicity surveys of low mass stars: Raghavan et. al. (2010) searched 454 solar-type stars and found a stellar multiplicity rate of 50%, and Winters et. al. (2017) surveyed 1121 M dwarfs and found a rate of 27%. A gap still remains in our understanding of the multiplicity rate of K dwarfs.For observational purposes, K-KIDS is confined equatorally to -30 < DEC < +30 to ensure that all stars are observable from either hemisphere, thereby creating a legacy sample that can be investigated for decades for stellar, brown dwarf, and planetary companions of various types. The RECONS team is conducting four companion surveys of these 1048 stars, including imaging surveys at various separations --- large (10+ arcseconds), medium (2–10 arcseconds), and small (0.02–2 arcseconds) --- and a radial velocity survey for the closest companions. Here we report on the small separation survey that targets scales similar to our Solar System, 0.1-100 AU, carried out using the Differential Speckle Survey Instrument on the Gemini and WIYN telescopes. To date, we have observed 964 out of 1048 systems, already finding 135 companions. We present a sample of K dwarf double stars with separations less than 100 AU, of which the vast majority are new discoveries. Further progress on the medium and large separation regimes ensures that a statistically significant stellar multiplicity rate for K dwarfs will soon be in achieved, which can then be investigated for dependences on, for example, stellar age and metallicity.This effort has been supported by the NSF through grant AST-1517413 and via observations obtained at the Gemini Observatory (North and South telescopes), which is operated by AURA under a cooperative agreement with the NSF on behalf of the

Wide field NEO survey 1.0-m telescope with 10 2k×4k mosaic CCD camera

NASA Astrophysics Data System (ADS)

Isobe, Syuzo; Asami, Atsuo; Asher, David J.; Hashimoto, Toshiyasu; Nakano, Shi-ichi; Nishiyama, Kota; Ohshima, Yoshiaki; Terazono, Junya; Umehara, Hiroaki; Yoshikawa, Makoto

2002-12-01

We developed a new 1.0 m telescope with a 3 degree flat focal plane to which a mosaic CCD camera with 10 2k×4k chips is fixed. The system was set up in February 2002, and is now undergoing the final fine adjustments. Since the telescope has a focal length of 3 m, a field of 7.5 square degrees is covered in one image. In good seeing conditions, 1.5 arc seconds, at the site located in Bisei town, Okayama prefecture in Japan, we can expect to detect down to 20th magnitude stars with an exposure time of 60 seconds. Considering a read-out time, 46 seconds, of the CCD camera, one image is taken in every two minutes, and about 2,100 square degrees of field is expected to be covered in one clear night. This system is very effective for survey work, especially for Near-Earth-Asteroid detection.

NMR characterization of sulphur substitution effects in the K xFe 2-ySe 2-xS z high-T c superconductor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Torchetti, D. A.; Imai, T.; Lei, H. C.

2012-04-17

We present a 77Se NMR study of the effect of S substitution in the high-T c superconductor K xFe 2-ySe 2-zS z in a temperature range up to 250 K. We examine two S concentrations, with z=0.8 (T c~ 26 K) and z=1.6 (nonsuperconducting). The samples containing sulphur exhibit broader NMR line shapes than the K xFe 2Se 2 sample due to local disorder in the Se environment. Our Knight shift 77K data indicate that in all samples, uniform spin susceptibility decreases with temperature, and that the magnitude of the Knight shift itself decreases with increased S concentration. In addition,more » S substitution progressively suppresses low-frequency spin fluctuations. None of the samples exhibit an enhancement of low-frequency antiferromagnetic spin fluctuations near T c in 1/T 1T, as seen in FeSe.« less

Superconducting and magnetic properties of Bi 2Sr 2Ca 1- xY xCu 2O y (0≦ x≦1)

NASA Astrophysics Data System (ADS)

Yoshizaki, R.; Saito, Y.; Abe, Y.; Ikeda, H.

1988-07-01

The effect of substitution of Y atoms for Ca atoms has been studied in the Bi 2Sr 2Ca 1- xY xCu 2O y compound system. For x<0.5, superconductivity is observed and its fractional volume is reduced with increasing x, though the transition temperature of about 85 K is maintained. For x≧0.5 samples, the electrical resistivity behavior can be well described by the three-dimensional variable range hopping conduction, indicating that the system is essentially insulating. In this range of x, magnetic susceptibility shows spin-glass-type cusp at 13 K in the heating process after zero-field cooling and an enhanced cusp at 11 K in the field-cooling process. In the temperature range above about 150 K the Curie-Weiss dependence holds well with a positive paramagnetic Curie temperature, which increases to 40 K with increasing x in the insulating region.

Critical current density and mechanism of vortex pinning in K xFe 2-ySe₂ doped with S

DOE PAGES

Lei, Hechang; Petrovic, C.

2011-08-15

We report the critical current density J c in K xFe 2-ySe 2-zS z crystals. The J c can be enhanced significantly with optimal S doping (z=0.99). For K 0.70(7)Fe 1.55(7)Se 1.01(2)S 0.99(2), the weak fishtail effect is found for H II c. The normalized vortex pinning forces follow the scaling law with a maximum position at 0.41 of the reduced magnetic field. These results demonstrate that the small size normal point defects dominate the vortex pinning mechanism.

Boston Public Schools K1 and K2 Programs Needs Assessment. Internal Report to the Department of Early Childhood, Boston Public Schools

ERIC Educational Resources Information Center

Marshall, Nancy L.; Roberts, Joanne; Mills, Linda

2006-01-01

The Boston Public Schools (BPS) Department of Early Childhood commissioned a needs assessment of current kindergarten (K2) and preschool (K1) programs (1) to inform the BPS Department of Early Childhood about professional development needs to improve the quality of existing K1 and K2 programs; and (2) to inform the Department of additional…

Mountain erosion over 10 yr, 10 k.y., and 10 m.y. time scales

Treesearch

James W. Kirchner; Robert C. Finkel; Clifford S. Riebe; Darryl E. Granger; James L. Clayton; John G. King; Walter F. Megahan

2001-01-01

We used cosmogenic 10Be to measure erosion rates over 10 k.y. time scales at 32 Idaho mountain catchments, ranging from small experimental watersheds (0.2 km2) to large river basins (35 000 km2). These long-term sediment yields are, on average, 17 times higher than stream sediment fluxes measured over...

Strong flux pinning at 4.2 K in SmBa2Cu3O y coated conductors with BaHfO3 nanorods controlled by low growth temperature

NASA Astrophysics Data System (ADS)

Miura, S.; Tsuchiya, Y.; Yoshida, Y.; Ichino, Y.; Awaji, S.; Matsumoto, K.; Ibi, A.; Izumi, T.

2017-08-01

In order to apply REBa2Cu3O y (REBCO, RE = rare earth elements or Y) coated conductors in high magnetic field, coil-based applications, the isotropic improvement of their critical current performance with respect to the directions of the magnetic field under these operating conditions is required. Most applications operate at temperatures lower than 50 K and magnetic fields over 2 T. In this study, the improvement of critical current density (J c) performance for various applied magnetic field directions was achieved by controlling the nanostructure of the BaHfO3 (BHO)-doped SmBa2Cu3O y (SmBCO) films on metallic substrates. The corresponding minimum J c value of the films at 40 K under an applied 3 T field was 5.2 MA cm-2, which is over ten times higher than that of a fully optimized Nb-Ti wire at 4.2 K. At 4.2 K, under a 17.5 T field, a flux pinning force density of 1.4 TN m-3 for B//c was realized; this value is among the highest values reported for REBCO films to date. More importantly, the F p for B//c corresponds to the minimum value for various applied magnetic field directions. We investigated the dominant flux pinning centers of films at 4.2 K using the anisotropic scaling approach based on the effective mass model. The dominant flux pinning centers are random pinning centers at 4.2 K, i.e., a high pinning performance was achieved by the high number density of random pins in the matrix of the BHO-doped SmBCO films.

Y2K+1: Technology, Community-College Students, the Millennium, and Stanley Kubrick's "2001: A Space Odyssey."

ERIC Educational Resources Information Center

Haspel, Paul

2002-01-01

Considers how screening Stanley Kubrick's "2001: A Space Odyssey" in a sophomore film class shows modern community-college students that millennial anxiety existed well before late 1999, the time of "Y2K" fears. Presents an assignment that examines "2001: A Space Odyssey" in the context of its time and in 2001. (SG)

NMR characterization of sulphur substitution effects in the K xFe 2-ySe 2-zS z high-T c superconductor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Torchetti, D. A.; Imai, T.; Lei, H. C.

2012-04-17

We present a⁷⁷ Se NMR study of the effect of S substitution in the high-T c superconductor K xFe 2-ySe 2-zS z in a temperature range up to 250 K. We examine two S concentrations, with z=0.8 (Tc~ 26 K) and z=1.6 (nonsuperconducting). The samples containing sulphur exhibit broader NMR line shapes than the K xFe₂Se₂ sample due to local disorder in the Se environment. Our Knight shift ⁷⁷K data indicate that in all samples, uniform spin susceptibility decreases with temperature, and that the magnitude of the Knight shift itself decreases with increased S concentration. In addition, S substitution progressivelymore » suppresses low-frequency spin fluctuations. None of the samples exhibit an enhancement of low-frequency antiferromagnetic spin fluctuations near T c in 1/T₁T, as seen in FeSe.« less

Steps for Action: Getting Intelligent Transportation Systems Ready for the Year 2000. Partners for ITS Y2K.

DOT National Transportation Integrated Search

1999-01-01

The purpose of this brochure is to serve as an organizing tool that will help you map out your Y2K problem-solving activities between now and January 1, 2000. During that period, the U.S. Department of Transportation will communicate the importance o...

Influence of microstructure on superconductivity in KxFe2−ySe2 and evidence for a new parent phase K2Fe7Se8

PubMed Central

Ding, Xiaxin; Fang, Delong; Wang, Zhenyu; Yang, Huan; Liu, Jianzhong; Deng, Qiang; Ma, Guobin; Meng, Chong; Hu, Yuhui; Wen, Hai-Hu

2013-01-01

The search for new superconducting materials has been spurred on by the discovery of iron-based superconductors whose structure and composition is qualitatively different from the cuprates. The study of one such material, KxFe2−ySe2 with a critical temperature of 32 K, is made more difficult by the fact that it separates into two phases—a dominant antiferromagnetic insulating phase K2Fe4Se5, and a minority superconducting phase whose precise structure is as yet unclear. Here we perform electrical and magnetization measurements, scanning electron microscopy and microanalysis, X-ray diffraction and scanning tunnelling microscopy on KxFe2−ySe2 crystals prepared under different quenching processes to better understand the relationship between its microstructure and its superconducting phase. We identify a three-dimensional network of superconducting filaments within this material and present evidence to suggest that the superconducting phase consists of a single Fe vacancy for every eight Fe-sites arranged in a √8 x √10 parallelogram structure. PMID:23695691

The influence of excess K2O on the electrical properties of (K,Na)1/2Bi1/2TiO3 ceramics

NASA Astrophysics Data System (ADS)

Li, Linhao; Li, Ming; Sinclair, Derek C.

2018-04-01

The solid solution (KxNa0.50-x)Bi0.50TiO3 (KNBT) between Na1/2Bi1/2TiO3 and K1/2Bi1/2TiO3 (KBT) has been extensively researched as a candidate lead-free piezoelectric material because of its relatively high Curie temperature and good piezoelectric properties, especially near the morphotropic phase boundary (MPB) at x ˜ 0.10 (20 mol. % KBT). Here, we show that low levels of excess K2O in the starting compositions, i.e., (Ky+0.03Na0.50-y)Bi0.50TiO3.015 (y-series), can significantly change the conduction mechanism and electrical properties compared to a nominally stoichiometric KNBT series (KxNa0.50-x)Bi0.50TiO3 (x-series). Impedance spectroscopy measurements reveal significantly higher bulk conductivity (σb) values for y ≥ 0.10 samples [activation energy (Ea) ≤ 0.95 eV] compared to the corresponding x-series samples which possess bandgap type electronic conduction (Ea ˜ 1.26-1.85 eV). The largest difference in electrical properties occurs close to the MPB composition (20 mol. % KBT) where y = 0.10 ceramics possess σb (at 300 °C) that is 4 orders of magnitude higher than that of x = 0.10 and the oxide-ion transport number in the former is ˜0.70-0.75 compared to <0.05 in the latter (between 600 and 800 °C). The effect of excess K2O can be rationalised on the basis of the (K + Na):Bi ratio in the starting composition prior to ceramic processing. This demonstrates the electrical properties of KNBT to be sensitive to low levels of A-site nonstoichiometry and indicates that excess K2O in KNBT starting compositions to compensate for volatilisation can lead to undesirable high dielectric loss and leakage currents at elevated temperatures.

Potassium rich rare earth (RE) borates K 3RE(BO 3) 2

NASA Astrophysics Data System (ADS)

Gao, J. H.; Li, R. K.

2008-01-01

A series of new compounds in the K 3RE(BO 3) 2 (RE = Y, Nd, Sm, Gd, Tb, Er and Lu) system were synthesized. Powder X-ray diffraction indicates that structures of the K 3RE(BO 3) 2 series can be separated into two different types with boundary between Gd and Tb. Single crystals of two representative compounds K 3Sm(BO 3) 2 and K 3Y(BO 3) 2 were obtained from a K 2O-B 2O 3 melt. The structure of K 3Y(BO 3) 2, determined from single crystal X-ray diffraction data, belongs to Pnnm space group, with lattice constants of a = 9.3377(9) Å, b = 6.7701(6) Å and c = 5.5058(4) Å. With a larger rare earth element, e.g. Sm 3+, K 3Sm(BO 3) 2 crystallizes in space group Pnma, with cell parameters of a = 9.046(3) Å, b = 7.100(2) Å and c = 11.186(3) Å. The structure of K 3Y(BO 3) 2 can be described as a three-dimensional framework formed by isolated YO 6 octahedra jointed by BO 3 triangles by sharing their apical oxygen atoms. The structure of K 3Sm(BO 3) 2 contains infinite [SmO 4BO 3] ∞ chains formed by corner sharing SmO 7 pentagonal dipyramid and BO 3 group, and those chains are interconnected by the other BO 3 groups.

The K2-HERMES Survey. I. Planet-candidate Properties from K2 Campaigns 1–3

NASA Astrophysics Data System (ADS)

Wittenmyer, Robert A.; Sharma, Sanjib; Stello, Dennis; Buder, Sven; Kos, Janez; Asplund, Martin; Duong, Ly; Lin, Jane; Lind, Karin; Ness, Melissa; Zwitter, Tomaz; Horner, Jonathan; Clark, Jake; Kane, Stephen R.; Huber, Daniel; Bland-Hawthorn, Joss; Casey, Andrew R.; De Silva, Gayandhi M.; D’Orazi, Valentina; Freeman, Ken; Martell, Sarah; Simpson, Jeffrey D.; Zucker, Daniel B.; Anguiano, Borja; Casagrande, Luca; Esdaile, James; Hon, Marc; Ireland, Michael; Kafle, Prajwal R.; Khanna, Shourya; Marshall, J. P.; Saddon, Mohd Hafiz Mohd; Traven, Gregor; Wright, Duncan

2018-02-01

Accurate and precise radius estimates of transiting exoplanets are critical for understanding their compositions and formation mechanisms. To know the planet, we must know the host star in as much detail as possible. We present first results from the K2-HERMES project, which uses the HERMES multi-object spectrograph on the Anglo-Australian Telescope to obtain R ∼ 28000 spectra of up to 360 stars in one exposure. This ongoing project aims to derive self-consistent spectroscopic parameters for about half of K2 target stars. We present complete stellar parameters and isochrone-derived masses and radii for 46 stars hosting 57 K2 candidate planets in Campaigns 1–3. Our revised host-star radii cast severe doubt on three candidate planets: EPIC 201407812.01, EPIC 203070421.01, and EPIC 202843107.01, all of which now have inferred radii well in excess of the largest known inflated Jovian planets.

2MASS - The 2 Micron All Sky Survey

NASA Technical Reports Server (NTRS)

Kleinmann, S. G.

1992-01-01

This paper describes a new sky survey to be carried out in three wavebands, J(1.25 m), H(1.65 m), and K(2.2 m). The limiting sensitivity of the survey, 10 sigma detection of point sources with K not greater than 14 mag, coupled with its all-sky coverage, were selected primarily to support studies of the large-scale structure of the Milky Way and the Local Universe. The survey requires construction of a pair of observing facilities, one each for the Northern and Southern Hemispheres. Operations are scheduled to begin in 1995. The data will begin becoming publicly available soon thereafter.

Test Of Astronomy STandards TOAST Survey of K-12 Teachers

NASA Astrophysics Data System (ADS)

Slater, Timothy F.; Slater, Stephanie; Stork, Debra J.

2015-01-01

Discipline-based education research in astronomy is focused on understanding the underlying mental mechanisms used by students when learning astronomy and teachers when teaching astronomy. Systematic surveys of K-12 teacher' knowledge in the domain of astronomy are conducted periodically in order to better focus and improve professional development. These surveys are most often done when doing contemporary needs assessments or when new assessment instruments are readily available. Designed by Stephanie J. Slater of the CAPER Center for Astronomy & Physics Education Research, the 29-item multiple-choice format Test Of Astronomy STandards - TOAST is a carefully constructed, criterion-referenced instrument constructed upon a solid list of clearly articulated and widely agreed upon learning objectives. The targeted learning concepts tightly align with the consensus learning goals stated by the American Astronomical Society - Chair's Conference on ASTRO 101, the American Association of the Advancement of Science's Project 2061 Benchmarks, and the National Research Council's 1996 National Science Education Standards. Without modification, the TOAST is also aligned with the significantly less ambitious 2013 Next Generation Science Standards created by Achieve, Inc., under the auspices of the National Research Council. This latest survey reveals that K-12 teachers still hold many of the same fundamental misconceptions uncovered by earlier surveys. This includes misconceptions about the size, scale, and structure of the cosmos as well as misconceptions about the nature of physical processes at work in astronomy. This suggests that professional development in astronomy is still needed and that modern curriculum materials are best served if they provide substantial support for implementation.

The Multiwavelength Survey by Yale-Chile (MUSYC): Wide K-Band Imaging, Photometric Catalogs, Clustering, and Physical Properties of Galaxies at z {approx} 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blanc, Guillermo A.; Lira, Paulina; Francke, Harold

2008-07-10

We present K-band imaging of two {approx}30{sup '} x 30{sup '} fields covered by the Multiwavelength Survey by Yale-Chile (MUSYC) Wide NIR Survey. The SDSS 1030+05 and Cast 1255 fields were imaged with the Infrared Side Port Imager (ISPI) on the 4 m Blanco telescope at the Cerro Tololo Inter-American Observatory (CTIO) to a 5 {sigma} point-source limiting depth of K {approx} 20 (Vega). Combining these data with the MUSYC optical UBVRIz imaging, we created multiband K-selected source catalogs for both fields. These catalogs, together with the MUSYC K-band catalog of the Extended Chandra Deep Field South (ECDF-S) field, weremore » used to select K < 20 BzK galaxies over an area of 0.71 deg{sup 2}. This is the largest area ever surveyed for BzK galaxies. We present number counts, redshift distributions, and stellar masses for our sample of 3261 BzK galaxies (2502 star-forming [sBzK] and 759 passively evolving [pBzK]), as well as reddening and star formation rate estimates for the star-forming BzK systems. We also present two-point angular correlation functions and spatial correlation lengths for both sBzK and pBzK galaxies and show that previous estimates of the correlation function of these galaxies were affected by cosmic variance due to the small areas surveyed. We have measured correlation lengths r{sub 0} of 8.89 {+-} 2.03 and 10.82 {+-} 1.72 Mpc for sBzK and pBzK galaxies, respectively. This is the first reported measurement of the spatial correlation function of passive BzK galaxies. In the {lambda}CDM scenario of galaxy formation, these correlation lengths at z {approx} 2 translate into minimum masses of {approx}4 x 10{sup 12} and {approx}9 x 10{sup 12} M{sub sun} for the dark matter halos hosting sBzK and pBzK galaxies, respectively. The clustering properties of the galaxies in our sample are consistent with their being the descendants of bright Lyman break galaxies at z {approx} 3, and the progenitors of present-day >1L{sup *} galaxies.« less

Waste Receiving and Processing (WRAP) Facility PMS Test Report For Data Management System (DMS) Security Test DMS-Y2K

DOE Office of Scientific and Technical Information (OSTI.GOV)

PALMER, M.E.

1999-09-21

Test Plan HNF-4351 defines testing requirements for installation of a new server in the WRAP Facility. This document shows the results of the test reports on the DMS-Y2K and DMS-F81 (Security) systems.

The platelet P2Y(12) receptor under normal and pathological conditions. Assessment with the radiolabeled selective antagonist [(3)H]PSB-0413.

PubMed

Ohlmann, Philippe; Lecchi, Anna; El-Tayeb, Ali; Müller, Christa E; Cattaneo, Marco; Gachet, Christian

2013-03-01

Various radioligands have been used to characterize and quantify the platelet P2Y(12) receptor, which share several weaknesses: (a) they are metabolically unstable and substrates for ectoenzymes, (b) they are agonists, and (c) they do not discriminate between P2Y(1) and P2Y(12). We used the [(3)H]PSB-0413 selective P2Y(12) receptor antagonist radioligand to reevaluate the number of P2Y(12) receptors in intact platelets and in membrane preparations. Studies in humans showed that: (1) [(3)H]PSB-0413 bound to 425 ± 50 sites/platelet (K (D) = 3.3 ± 0.6 nM), (2) 0.5 ± 0.2 pmol [(3)H]PSB-0413 bound to 1 mg protein of platelet membranes (K (D) = 6.5 ± 3.6 nM), and (3) competition studies confirmed the known features of P2Y(12), with the expected rank order of potency: AR-C69931MX > 2MeSADP ≫ ADPβS > ADP, while the P2Y(1) ligand MRS2179 and the P2X(1) ligand α,β-Met-ATP did not displace [(3)H]PSB-0413 binding. Patients with severe P2Y(12) deficiency displayed virtually no binding of [(3)H]PSB-0413 to intact platelets, while a patient with a dysfunctional P2Y(12) receptor had normal binding. Studies in mice showed that: (1) [(3)H]PSB-0413 bound to 634 ± 87 sites/platelet (K (D) = 14 ± 4.5 nM) and (2) 0.7 pmol ± 0.3 [(3)H]PSB-0413 bound to 1 mg protein of platelet membranes (K (D) = 9.1 ± 5.3 nM). Clopidogrel and other thiol reagents like pCMBS or DTT abolished the binding both to intact platelets and membrane preparations. Therefore, [(3)H]PSB-0413 is an accurate and selective tool for radioligand binding studies aimed at quantifying P2Y(12) receptors, to identify patients with P2Y(12) deficiencies or quantify the effect of P2Y(12) targeting drugs.

Giant increase in critical current density of K xFe 2-ySe₂ single crystals

DOE PAGES

Lei, Hechang; Petrovic, C.

2011-12-28

The critical current density Jabc of K xFe 2-ySe₂ single crystals can be enhanced by more than one order of magnitude, up to ~2.1×10⁴ A/cm² by the post annealing and quenching technique. A scaling analysis reveals the universal behavior of the normalized pinning force as a function of the reduced field for all temperatures, indicating the presence of a single vortex pinning mechanism. The main pinning sources are three-dimensional (3D) point-like normal cores. The dominant vortex interaction with pinning centers is via spatial variations in critical temperature T c (“δT c pinning”).

Synthesis and structural characterization of Li3K3Y7(BO3)9

NASA Astrophysics Data System (ADS)

Bräuchle, Sebastian; Huppertz, Hubert

2017-09-01

Li3K3Y7(BO3)9 was prepared by high-temperature solid state synthesis at 900 °C in a platinum crucible from lithium carbonate, potassium carbonate, boric acid, and yttrium(III) oxide. The compound crystallizes in the orthorhombic space group Pca21 (no. 29) (Z = 4). The structure was refined from single-crystal X-ray diffraction data: a = 20.743(8), b = 6.387(4), c = 17.474(4) Å, V = 2315.2(2) Å3, R1 = 0.0473, and wR2 = 0.0637 for all data. The crystal structure of Li3K3Y7(BO3)9 consists of isolated BO3 groups forming [Li3B4O21] units in combination with LiO6 octahedra in the ac plane, which are interconnected to each other by additional planar BO3 groups. The Y3+ and K+ cations are arranged in layers along the a-axis.

Photoluminescence studies of high-efficient red-emitting K{sub 2}Y(WO{sub 4})(PO{sub 4}):Eu{sup 3+} phosphor for NUV LED

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Xinguo; State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275; Chen, Mengyang

Highlights: • Novel K{sub 2}Y(WO{sub 4})(PO{sub 4}):Eu{sup 3+} red phosphors were prepared by solid-state method. • Phosphors exhibit strong red light under NUV excitation with quantum efficiency of 70.5 %. • Judd–Ofelt analysis ascertains the presence of Eu{sup 3+} in a highly asymmetric environment. • The red LED prototype was fabricated with KYWP:Eu{sup 3+} phosphor and InGaN chip. - Abstract: A series of high-efficient red-emitting phosphors K{sub 2}Y(WO{sub 4})(PO{sub 4}):Eu{sup 3+} have been successfully synthesized by conventional solid-state reaction, and its photoluminescence (PL) properties have been investigated. The phosphors can be excited efficiently by NUV light, then exhibit strong redmore » emission with quantum efficiency of 70.5%. The concentration quenching takes place at relatively high concentration of Eu{sup 3+} (x = 0.70), which is further confirmed by the variation of decay curves of the entitled phosphors. Judd–Ofelt analysis ascertains the presence of Eu{sup 3+} in a highly asymmetric environment. The phosphor exhibits good thermal stability (92.5% at 100 °C and 84.1% at 180 °C). The red LED prototype fabricated by opyimized-composition K{sub 2}Y(WO{sub 4})(PO{sub 4}):0.70Eu{sup 3+} phosphor and 395 nm-emitting InGaN chips exhibit bright red emission. The results indicate that the K{sub 2}Y(WO{sub 4})(PO{sub 4}):Eu{sup 3+} phosphors are promising red phosphors for NUV LED.« less

Detailed characterization of thermal expansion tensor in monoclinic K Re(WO 4) 2 (where Re = Gd, Y, Lu, Yb)

NASA Astrophysics Data System (ADS)

Loiko, P. A.; Yumashev, K. V.; Kuleshov, N. V.; Rachkovskaya, G. E.; Pavlyuk, A. A.

2011-11-01

Linear thermal expansion coefficients αT were measured in monoclinic potassium (rare-earth) double tungstates K Re(WO 4) 2 ( Re = Gd, Y, Lu, Yb) by a dilatometric technique in the directions of a1, b1, c1∗ crystallographic axes (I2/c space group) and optical indicatrix axes Nm and Ng. Thermal expansion tensor αij was evaluated in the { Nm, Np, Ng} frame and then diagonalized. The orientation of corresponding frame {Xi'} with respect to crystallographic and optical indicatrix frames was determined, considering two different crystallographic settings (C2/c and I2/c). Potassium lutetium tungstate KLu(WO 4) 2 was found to possess the lower thermal expansion anisotropy among K Re(WO 4) 2 family. Athermal orientations of laser elements were proposed for K Re(WO 4) 2-based lasers under diode pumping, taking into account temperature dependence of the refractive index and bulging of crystal end faces.

Campaign 9 of the K2 Mission: Observational Parameters, Scientific Drivers, and Community Involvement for a Simultaneous Space- and Ground-based Microlensing Survey

NASA Technical Reports Server (NTRS)

Henderson, Calen B.; Poleski, Radoslaw; Penny, Matthew; Street, Rachel A.; Bennett, David P.; Hogg, David W.; Gaudi, B. Scott; Zhu, W.; Barclay, T.; Barentsen, G.;

Vitamin K policies and midwifery practice: questionnaire survey

PubMed Central

Ansell, Pat; Roman, Eve; Fear, Nicola T; Renfrew, Mary J

2001-01-01

Objectives To investigate policies on neonatal vitamin K and their implementation. Design Two phase postal survey. Setting United Kingdom. Participants A 10% random sample of midwives registered with the United Kingdom Central Council for nursing, midwifery, and health visiting. Of 3191 midwives in the sample, 2515 (79%) responded to phase one and 2294 (72%) completed questionnaires on their current jobs (November 1998 to May 1999). In phase two, 853 (62%) of 1383 eligible midwives gave details on 2179 of their earliest jobs (start dates before 1990). Results All the midwives in clinical practice at the time of the survey (2271, 99%) reported that they were working in areas with official policies on neonatal vitamin K. Seven distinct policies were described: intramuscular vitamin K for all babies (1159, 51.0%); intramuscular vitamin K for babies at “high risk,” oral for others (470, 20.7%); oral vitamin K for all babies (323, 14.2%); parental choice for all (124, 5.5%); parental choice for all except babies at high risk, (119, 5.2%); intramuscular vitamin K for babies at high risk only (33, 1.5%); oral vitamin K for babies at high risk only (17, 0.7%); and a disparate group of policies including intravenous vitamin K for some babies (26, 1.1%). Previous policies were (and some may still be) open to individual interpretation and were not always followed. Conclusions Hospital policy is not necessarily a good guide to individual practice. The primary purpose of clinical records is to document patient care, and recording practices reflect this. There is considerable variation in vitamin K policies and midwifery practice in the United Kingdom, and there is no clear consensus on which babies should receive vitamin K intramuscularly. What is already known on this topicNeonatal administration of vitamin K by the intramuscular route is effective in the prevention of haemorrhagic disease in newborn babies but has been suggested as a possible risk factor for leukaemia in

K-Ca Dating of Alkali-Rich Fragments in the Y-74442 and Bhola LL-Chondritic Breccias

NASA Technical Reports Server (NTRS)

Yokoyama, T; Misawa, K.; Okano, O; Shih, C. -Y.; Nyquist, L. E.; Simon, J. I.; Tappa, M. J.; Yoneda, S.

2013-01-01

Alkali-rich igneous fragments in the brecciated LL-chondrites, Krahenberg (LL5) [1], Bhola (LL3-6) [2], Siena (LL5) [3] and Yamato (Y)-74442 (LL4) [4-6], show characteristic fractionation patterns of alkali and alkaline elements [7]. The alkali-rich fragments in Krahenberg, Bhola and Y-74442 are very similar in mineralogy and petrography, suggesting that they could have come from related precursor materials [6]. Recently we reported Rb-Sr isotopic systematics of alkali-rich igneous rock fragments in Y-74442: nine fragments from Y-74442 yield the Rb-Sr age of 4429 plus or minus 54 Ma (2 sigma) for lambda(Rb-87) = 0.01402 Ga(exp -1) [8] with the initial ratio of Sr-87/Sr-86 = 0.7144 plus or minus 0.0094 (2 sigma) [9]. The Rb-Sr age of the alkali-rich fragments of Y-74442 is younger than the primary Rb-Sr age of 4541 plus or minus 14 Ma for LL-chondrite whole-rock samples [10], implying that they formed after accumulation of LL-chondrite parental bodies, although enrichment may have happened earlier. Marshall and DePaolo [11,12] demonstrated that the K-40 - Ca-40 decay system could be an important chronometer as well as a useful radiogenic tracer for studies of terrestrial rocks. Shih et al. [13,14] and more recently Simon et al. [15] determined K-Ca ages of lunar granitic rocks, and showed the application of the K-Ca chronometer for K-rich planetary materials. Since alkali-rich fragments in the LL-chondritic breccias are highly enriched in K, we can expect enhancements of radiogenic Ca-40. Here, we report preliminary results of K-Ca isotopic systematics of alkali-rich fragments in the LL-chondritic breccias, Y-74442 and Bhola.

VizieR Online Data Catalog: UKIDSS-DR8 LAS, GCS and DXS Surveys (Lawrence+ 2012)

NASA Astrophysics Data System (ADS)

Lawrence, A.; Warren, S. J.; Almaini, O.; Edge, A. C.; Hambly, N. C.; Jameson, R. F.; Lucas, P.; Casali, M.; Adamson, A.; Dye, S.; Emerson, J. P.; Foucaud, S.; Hewett, P.; Hirst, P.; Hodgkin, S. T.; Irwin, M. J.; Lodieu, N.; McMahon, R. G.; Simpson, C.; Smail, I.; Mortlock, D.; Folger, M.

2012-03-01

The UKIRT Infrared Deep Sky Survey (UKIDSS) is a large-scale near-IR survey which aim is to cover 7500 square degrees of the Northern sky. The survey is carried out using the Wide Field Camera (WFCAM), with a field of view of 0.21 square degrees, mounted on the 3.8m United Kingdom Infra-red Telescope (UKIRT) in Hawaii. The project comprises five surveys (LAS, GCS, DXS, GPS and UDS). The Large Area Survey (LAS) covers an area of 4000 square degrees in high Galactic latitudes (extragalactic) in the four bands Y(1.0um) J(1.2um) H(1.6um) and K(2.2um) to a depth of K=18.4. The Galactic Clusters Survey (GCS) aims to survey ten large open star clusters and star formation associations, covering a total of 1067 square degrees in the five bands Z (0.9um), Y(1.0um) J(1.2um) H(1.6um) and K(2.2um), plus a second pass in K for proper motions, to a depth of Z=20.4, Y=20.3, J=19.5, H=18.6, K=18.6. The Deep Extragalactic Survey (DXS) aims to map 35 square degrees of sky to a 5-σ point-source sensitivity of J=22.3 and K=20.8 in four carefully selected, multi-wavelength survey areas. The central regions of each field will also be mapped to H=21.8. The primary aim of the survey is to produce a photometric galaxy sample at a redshift of 1-2, within a volume comparable to that of the SDSS, selected in the same passband (rest frame optical). Details of the surveys can be found in the in the paper by Lawrence et al. (2007MNRAS.379.1599L), and at the UKIDSS Surveys site (http://www.ukidss.org/surveys/surveys.html). The data described here represent a subset of the UKIDSS data, limited to the public data and most representative columns. In the "Byte-by-byte Description" below the original names of the columns are given as bracketed names. (3 data files).

Deep CFHT Y-band Imaging of VVDS-F22 Field. II. Quasar Selection and Quasar Luminosity Function

NASA Astrophysics Data System (ADS)

Yang, Jinyi; Wu, Xue-Bing; Liu, Dezi; Fan, Xiaohui; Yang, Qian; Wang, Feige; McGreer, Ian D.; Fan, Zuhui; Yuan, Shuo; Shan, Huanyuan

2018-03-01

We report the results of a faint quasar survey in a one-square-degree field. The aim is to test the Y-K/g-z and J-K/i-Y color selection criteria for quasars at faint magnitudes to obtain a complete sample of quasars based on deep optical and near-infrared color–color selection and to measure the faint end of the quasar luminosity function (QLF) over a wide redshift range. We carried out a quasar survey based on the Y-K/g-z and J-K/i-Y quasar selection criteria, using the deep Y-band data obtained from our CFHT/WIRCam Y-band images in a two-degree field within the F22 field of the VIMOS VLT deep survey, optical co-added data from Sloan Digital Sky Survey Stripe 82 and deep near-infrared data from the UKIDSS Deep Extragalactic Survey in the same field. We discovered 25 new quasars at 0.5< z< 4.5 and i< 22.5 mag within one-square-degree field. The survey significantly increases the number of faint quasars in this field, especially at z∼ 2{--}3. It confirms that our color selections are highly complete in a wide redshift range (z< 4.5), especially over the quasar number density peak at z∼ 2{--}3, even for faint quasars. Combining all previous known quasars and new discoveries, we construct a sample with 109 quasars and measure the binned QLF and parametric QLF. Although the sample is small, our results agree with a pure luminosity evolution at lower redshift and luminosity evolution and density evolution model at redshift z> 2.5.

New England's travel and tourism markets: trends in geographic target markets beyond the 90s--the y2k decade

Treesearch

Rodney B. Warnick

2009-01-01

The purpose of this paper is to examine the travel and lifestyle activity trends in the years beyond the 1990s--the Y2K decade--for geographic markets of interest to New England travel destinations. The central theme is examining New England's potential primary, secondary, and tertiary geographic markets in detail.

Effect of K3PO4 addition as sintering inhibitor during calcination of Y2O3 nanoparticles

NASA Astrophysics Data System (ADS)

Soga, K.; Okumura, Y.; Tsuji, K.; Venkatachalam, N.

2009-11-01

Erbium-doped yttrium oxide nanoparticle is one of the most important for fluorescence bioimaging under near infrared excitation. Particle size of it below 100 nm is an important requirement for a cellular bioimaging. However, the synthesis with such small particles is difficult at the calcination temperature above 1200 °C due to the sintering and crystal growth of the particles. In this study, yttrium oxide nanoparticles with average size of 30 nm were successfully synthesized by using K3PO4 as a sintering inhibitor during the calcination. A single phase of cubic Y2O3 as the resultant material was confirmed by XRD, which was also confirmed to emit a bright upconversion emission under 980-nm excitation. Improvement of chemical durability due to the introduction of phosphate group on the surface of the Y2O3 particles is also reported.

77Se NMR Investigation of the KxFe2−ySe2 high-Tc Superconductor (Tc = 33 K)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petrovic, C.; Torchetti, D.A. Fu, M.; Christensen, D.C.

2011-03-18

We report comprehensive {sup 77}Se NMR measurements on a single crystalline sample of the recently discovered FeSe-based high-temperature superconductor K{sub x}Fe{sub 2-y}Se{sub 2} (T{sub c} = 33 K) in a broad temperature range up to 290 K. Despite deviations from the stoichiometric KFe{sub 2}Se{sub 2} composition, we observed {sup 77}Se NMR line shapes as narrow as 4.5 kHz under a magnetic field applied along the crystal c axis, and found no evidence for co-existence of magnetic order with superconductivity. On the other hand, the {sup 77}Se NMR line shape splits into two peaks with equal intensities at all temperatures whenmore » we apply the magnetic field along the ab plane. This suggests that K vacancies may have a superstructure and that the local symmetry of the Se sites is lower than the tetragonal fourfold symmetry of the average structure. This effect might be a prerequisite for stabilizing the s{sub {+-}} symmetry of superconductivity in the absence of the hole bands at the Brillouin zone center. From the increase of NMR linewidth below T{sub c} induced by the Abrikosov lattice of superconducting vortices, we estimate the in-plane penetration depth {lambda}{sub ab} {approx} 290 nm and the carrier concentration n{sub e} {approx} 1 x 10{sup +21} cm{sup -3}. Our Knight shift {sup 77}K data indicate that the uniform spin susceptibility decreases progressively with temperature, in analogy with the case of FeSe (T{sub c} {approx} 9 K) as well as other FeAs high-T{sub c} systems. The strong suppression of {sup 77}K observed immediately below T{sub c} for all crystal orientations is consistent with a singlet pairing of Cooper pairs. We do not however observe the Hebel-Slichter coherence peak of the nuclear spin-lattice relaxation rate 1/T1 immediately below T{sub c}, expected for conventional BCS s-wave superconductors. In contrast with the case of FeSe, we do not observe evidence for an enhancement of low-frequency antiferromagnetic spin fluctuations near T

Solid strong base K-Pt/NaY zeolite nano-catalytic system for completed elimination of formaldehyde at room temperature

NASA Astrophysics Data System (ADS)

Song, Shaoqing; Wu, Xi; Lu, Changhai; Wen, Meicheng; Le, Zhanggao; Jiang, Shujuan

2018-06-01

Solid strong base nano-catalytic system of K-modification NaY zeolite supported 0.08% Pt (K-Pt/NaY) were constructed for eliminating HCHO at room temperature. In the catalytic process, activation energy over K-Pt/NaY nano-catalytic system was greatly decreased along with the enhanced reaction rate. Characterization and catalytic tests revealed the surface electron structure of K-Pt/NaY was improved, as reflected by the enhanced HCHO adsorption capability, high sbnd OH concentration, and low-temperature reducibility. Therefore, the optimal K-Pt/NaY showed high catalytic efficiency and strong H2O tolerance for HCHO elimination by directly promoting the reaction between active sbnd OH and formate species. These results may suggest a new way for probing the advanced solid strong base nano-catalytic system for the catalytic elimination of indoor HCHO.

Suppression of the antiferromagnetic order when approaching the superconducting state in a phase-separated crystal of K x Fe 2 - y Se 2

DOE PAGES

Li, Shichao; Gan, Yuan; Wang, Jinghui; ...

2017-09-06

Here, we combined elastic and inelastic neutron scattering techniques, magnetic susceptibility, and resistivity measurements to study single-crystal samples of K xFe 2-ySe 2, which contain the superconducting phase that has a transition temperature of ~31 K. In the inelastic neutron scattering measurements, we also observe both the spin-wave excitations resulting from the block antiferromagnetic ordered phase and the resonance that is associated with the superconductivity in the superconducting phase, demonstrating the coexistence of these two orders. From the temperature dependence of the intensity of the magnetic Bragg peaks, we find that well before entering the superconducting state, the development ofmore » the magnetic order is interrupted, at ~42 K. We consider this result to be evidence for the physical separation of the antiferromagnetic and superconducting phases; the suppression is possibly due to the proximity effect of the superconducting fluctuations on the antiferromagnetic order.« less

Suppression of the antiferromagnetic order when approaching the superconducting state in a phase-separated crystal of K x Fe 2 - y Se 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Shichao; Gan, Yuan; Wang, Jinghui

Here, we combined elastic and inelastic neutron scattering techniques, magnetic susceptibility, and resistivity measurements to study single-crystal samples of K xFe 2-ySe 2, which contain the superconducting phase that has a transition temperature of ~31 K. In the inelastic neutron scattering measurements, we also observe both the spin-wave excitations resulting from the block antiferromagnetic ordered phase and the resonance that is associated with the superconductivity in the superconducting phase, demonstrating the coexistence of these two orders. From the temperature dependence of the intensity of the magnetic Bragg peaks, we find that well before entering the superconducting state, the development ofmore » the magnetic order is interrupted, at ~42 K. We consider this result to be evidence for the physical separation of the antiferromagnetic and superconducting phases; the suppression is possibly due to the proximity effect of the superconducting fluctuations on the antiferromagnetic order.« less

Y1Ba2Cu3O(6+delta) growth on thin Y-enhanced SiO2 buffer layers on silicon

NASA Technical Reports Server (NTRS)

Robin, T.; Mesarwi, A.; Wu, N. J.; Fan, W. C.; Espoir, L.; Ignatiev, A.; Sega, R.

1991-01-01

SiO2 buffer layers as thin as 2 nm have been developed for use in the growth of Y1Ba2Cu3O(6+delta) thin films on silicon substrates. The SiO2 layers are formed through Y enhancement of silicon oxidation, and are highly stoichiometric. Y1Ba2Cu3O(6+delta) film growth on silicon with thin buffer layers has shown c orientation and Tc0 = 78 K.

The Snapshot A-Star SurveY (SASSY)

NASA Astrophysics Data System (ADS)

Garani, Jasmine; Nielsen, Eric L.; Marchis, Franck; Liu, Michael C.; Macintosh, Bruce; Rajan, Abhijith; De Rosa, Robert J.; Wang, Jason; Esposito, Thomas; Best, William M. J.; Bowler, Brendan P.; Dupuy, Trent J.; Ruffio, Jean-Baptise

2017-01-01

We present the Snapshot A-Star SurveY (SASSY), an adaptive optics survey conducted using NIRC2 on the Keck II telescope to search for young, self-luminious planets and brown dwarfs (M > 5MJup) around high mass stars (M > 1.5 M⊙). We describe a custom data-reduction pipeline developed for the coronagraphic observations of our 200 target stars. Our data analysis method includes basic near infrared data processing (flat-field correction, bad pixel removal, distortion correction) as well as performing PSF subtraction through a Reference Differential Imaging algorithm based on a library of PSFs derived from the observations using the pyKLIP routine. We present early results from the survey including planet and brown dwarf candidates and the status of ongoing follow-up observations. Utilizing the high contrast of Keck NIRC2 coronagraphic observations, SASSY reaches sensitivity to brown dwarfs and planetary mass companions at separations between 0.6'' and 4''. With over 200 stars observed we are tripling the number of high-mass stars imaged at these contrasts and sensitivities compared to previous surveys. This work was supported by the NSF REU program at the SETI Institute and NASA grant NNX14AJ80G.

Formation mechanism of superconducting phase and its three-dimensional architecture in pseudo-single-crystal K xFe 2-ySe 2

DOE PAGES

Liu, Yong; Xing, Qingfeng; Straszheim, Warren E.; ...

2016-02-11

Here, we report how the superconducting phase forms in pseudo-single-crystal K xFe 2-ySe 2. In situ scanning electron microscopy (SEM) observation reveals that, as an order-disorder transition occurs, on cooling, most of the high-temperature iron-vacancy-disordered phase gradually changes into the iron-vacancy-ordered phase whereas a small quantity of the high-temperature phase retains its structure and aggregates to the stripes with more iron concentration but less potassium concentration compared to the iron-vacancy-ordered phase. The stripes that are generally recognized as the superconducting phase are actually formed as a remnant of the high-temperature phase with a compositional change after an “imperfect” order-disorder transition.more » It should be emphasized that the phase separation in pseudo-single-crystal K xFe 2-ySe 2 is caused by the iron-vacancy order-disorder transition. The shrinkage of the high-temperature phase and the expansion of the newly created iron-vacancy-ordered phase during the phase separation rule out the mechanism of spinodal decomposition proposed in an early report [Wang et al, Phys. Rev. B 91, 064513 (2015)]. Since the formation of the superconducting phase relies on the occurrence of the iron-vacancy order-disorder transition, it is impossible to synthesize a pure superconducting phase by a conventional solid state reaction or melt growth. By focused ion beam-scanning electron microscopy, we further demonstrate that the superconducting phase forms a contiguous three-dimensional architecture composed of parallelepipeds that have a coherent orientation relationship with the iron-vacancy-ordered phase.« less

Factors controlling volume errors through 2D gully erosion assessment: guidelines for optimal survey design

NASA Astrophysics Data System (ADS)

Castillo, Carlos; Pérez, Rafael

2017-04-01

The assessment of gully erosion volumes is essential for the quantification of soil losses derived from this relevant degradation process. Traditionally, 2D and 3D approaches has been applied for this purpose (Casalí et al., 2006). Although innovative 3D approaches have recently been proposed for gully volume quantification, a renewed interest can be found in literature regarding the useful information that cross-section analysis still provides in gully erosion research. Moreover, the application of methods based on 2D approaches can be the most cost-effective approach in many situations such as preliminary studies with low accuracy requirements or surveys under time or budget constraints. The main aim of this work is to examine the key factors controlling volume error variability in 2D gully assessment by means of a stochastic experiment involving a Monte Carlo analysis over synthetic gully profiles in order to 1) contribute to a better understanding of the drivers and magnitude of gully erosion 2D-surveys uncertainty and 2) provide guidelines for optimal survey designs. Owing to the stochastic properties of error generation in 2D volume assessment, a statistical approach was followed to generate a large and significant set of gully reach configurations to evaluate quantitatively the influence of the main factors controlling the uncertainty of the volume assessment. For this purpose, a simulation algorithm in Matlab® code was written, involving the following stages: - Generation of synthetic gully area profiles with different degrees of complexity (characterized by the cross-section variability) - Simulation of field measurements characterised by a survey intensity and the precision of the measurement method - Quantification of the volume error uncertainty as a function of the key factors In this communication we will present the relationships between volume error and the studied factors and propose guidelines for 2D field surveys based on the minimal survey

Structure and temperature-dependent phase transitions of lead-free Bi 1/2Na 1/2TiO 3-Bi 1/2K 1/2TiO 3-K 0.5Na 0.5NbO 3 piezoceramics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anton, Eva-Maria; Schmitt, Ljubomira Ana; Hinterstein, Manuel

2014-05-28

Structure and phase transitions of (1-y)((1-x)Bi 1/2Na 1/2TiO 3-xBi 1/2K 1/2TiO 3)-yK 0.5Na 0.5NbO 3 (x; y) piezoceramics (0.1 ≤ x ≤ 0.4; 0 ≤ y ≤ 0.05) were investigated by transmission electron microscopy, neutron diffraction, temperature-dependent x-ray diffraction, and Raman spectroscopy. The local crystallographic structure at room temperature (RT) does not change by adding K 0.5Na 0.5NbO 3 to Bi 1/2Na 1/2TiO 3-xBi 1/2K 1/2TiO 3 for x = 0.2 and 0.4. The average crystal structure and microstructure on the other hand develop from mainly long-range polar order with ferroelectric domains to short-range order with polar nanoregions displaying amore » more pronounced relaxor character. The (0.1; 0) and (0.1; 0.02) compositions exhibit monoclinic Cc space group symmetry, which transform into Cc + P4bm at 185 and 130 °C, respectively. This high temperature phase is stable at RT for the morphotropic phase boundary compositions of (0.1; 0.05) and all compositions with x = 0.2. For the compositions of (0.1; 0) and (0.1; 0.02), local structural changes on heating are evidenced by Raman; for all other compositions, changes in the long-range average crystal structure were observed.« less

Fe-vacancy ordering in superconducting K 1–xFe 2–ySe 2: First-principles calculations and Monte Carlo simulations

DOE PAGES

Fang, Yong; Tai, Yuan -Yen; Deng, Junkai; ...

2015-07-20

Fe vacancies in the 33 K superconductor K 1–xFe 2–ySe 2 show ordering schemes that may be correlated with its superconducting properties. First-principles calculations and kinetic Monte Carlo simulations lead to a very simple model for vacancy ordering. Repulsive dipolar interactions between Fe vacancies show three ground states: amore » $$\\sqrt{8}\\times \\sqrt{10}$$ rhombus-ordered structure for 12.5% vacancies, a $$\\sqrt{5}\\times \\sqrt{5}$$ squared lattice for 20% vacancies, and a $$\\sqrt{5}\\times \\sqrt{5}$$ rhombus-ordered structure for 25% vacancies. Other structural states are derived from these three ground states and may contain additional disordered spatial regions. As a result, the repulsive interaction between Fe vacancies arises from enhanced Fe–Se covalent bonds, which differs from the well-known attractive interaction of Fe vacancies in body-centered cubic Fe.« less

Identification of 6H1 as a P2Y purinoceptor: P2Y5.

PubMed

Webb, T E; Kaplan, M G; Barnard, E A

1996-02-06

We have determined the identity of the orphan G-protein coupled receptor cDNA, 6H1, present in activated chicken T cells, as a subtype of P2Y purinoceptor. This identification is based on first on the degree of sequence identity shared with recently cloned members of the P2Y receptor family and second on the pharmacological profile. Upon transient expression in COS-7 cells the 6H1 receptor bound the radiolabel [35S]dATP alpha S specifically and with high affinity (Kd, 10 nM). This specific binding could be competitively displaced by a range of ligands active at P2 purinoceptors, with ATP being the most active (K (i)), 116 nM). Such competition studies have established the following rank order of activity: ATP ADP 2-methylthioATP alpha, beta-methylene ATP, UTP, thus confirming 6H1 as a member of the growing family of P2Y purinoceptors. As the fifth receptor of this type to be identified we suggest that it be named P2Y5.

VizieR Online Data Catalog: Radio continuum survey of Kepler K2 mission Field 1 (Tingay+, 2016)

NASA Astrophysics Data System (ADS)

Tingay, S. J.; Hancock, P. J.; Wayth, R. B.; Intema, H.; Jagannathan, P.; Mooley, K.

2016-10-01

We describe contemporaneous observations of K2 Field 1 with the Murchison Widefield Array (MWA) and historical (from 2010-2012) observations from the Tata Institute of Fundamental Research (TIFR) Giant Metrewave Radio Telescope (GMRT) Sky Survey (TGSS; http://tgss.ncra.tifr.res.in/), via the TGSS Alternative Data Release 1 (ADR1; Intema et al. 2016, in prep.). The MWA and GMRT are radio telescopes operating at low radio frequencies (approximately 140-200MHz for the work described here). K2 mission Campaign 1 was conducted on Field 1 (center at R.A.=11:35:45.51; decl.=+01:25:02.28; J2000), covering the North Galactic Cap, between 2014 May 30 and August 21. The parameters of MWA observations are described in Table1, showing the 15 observations conducted over a period of approximately one month in 2014 June and July. All observations were made in a standard MWA imaging mode with a 30.72MHz bandwidth consisting of 24 contiguous 1.28MHz "coarse channels", each divided into 32 "fine channels" each of 40kHz bandwidth (total of 768 fine channels across 30.72MHz). The temporal resolution of the MWA correlator output was set to 0.5s. All observations were made in full polarimetric mode, with all Stokes parameters formed from the orthogonal linearly polarized feeds. Observations were made at two center frequencies, 154.88 and 185.60MHz, with two 296s observations of the K2 field at each frequency on each night of observation, accompanied by observations of one of three calibrators (Centaurus A, Virgo A, or Hydra A) at each frequency, with 112s observations. The observed fields were tracked, and thus, due to the fixed delay settings available to point the MWA primary beam, the tracked R.A. and decl. changes slightly between different observations (always a very small change compared to the MWA field of view). The total volume of MWA visibility data processed was approximately 2.2TB. A full survey of the radio sky at 150MHz as visible from the Giant Metrewave Radio (GMRT) was

Effects of nano-YAG (Y 3Al 5O 12) crystallization on the structure and photoluminescence properties of Nd 3+-doped K 2O-SiO 2-Y 2O 3-Al 2O 3 glasses

NASA Astrophysics Data System (ADS)

Tarafder, Anal; Molla, Atiar Rahaman; Karmakar, Basudeb

2010-10-01

Nd 3+-doped precursor glass in the K 2O-SiO 2-Y 2O 3-Al 2O 3 (KSYA) system was prepared by the melt-quench technique. The transparent Y 3Al 5O 12 (YAG) glass-ceramics were derived from this glass by a controlled crystallization process at 750 °C for 5-100 h. The formation of YAG crystal phase, size and morphology with progress of heat-treatment was examined by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and Fourier transformed infrared reflectance spectroscopy (FT-IRRS). The crystallite sizes obtained from XRD are found to increase with heat-treatment time and vary in the range 25-40 nm. The measured photoluminescence spectra have exhibited emission transitions of 4F 3/2 → 4I J ( J = 9/2, 11/2 and 13/2) from Nd 3+ ions upon excitation at 829 nm. It is observed that the photoluminescence intensity and excited state lifetime of Nd 3+ ions decrease with increase in heat-treatment time. The present study indicates that the incorporation of Nd 3+ ions into YAG crystal lattice enhance the fluorescence performance of the glass-ceramic nanocomposites.

Star clusters and K2

NASA Astrophysics Data System (ADS)

Dotson, Jessie; Barentsen, Geert; Cody, Ann Marie

2018-01-01

The K2 survey has expanded the Kepler legacy by using the repurposed spacecraft to observe over 20 star clusters. The sample includes open and globular clusters at all ages, including very young (1-10 Myr, e.g. Taurus, Upper Sco, NGC 6530), moderately young (0.1-1 Gyr, e.g. M35, M44, Pleiades, Hyades), middle-aged (e.g. M67, Ruprecht 147, NGC 2158), and old globular clusters (e.g. M9, M19, Terzan 5). K2 observations of stellar clusters are exploring the rotation period-mass relationship to significantly lower masses than was previously possible, shedding light on the angular momentum budget and its dependence on mass and circumstellar disk properties, and illuminating the role of multiplicity in stellar angular momentum. Exoplanets discovered by K2 in stellar clusters provides planetary systems ripe for modeling given the extensive information available about their ages and environment. I will review the star clusters sampled by K2 across 16 fields so far, highlighting several characteristics, caveats, and unexplored uses of the public data set along the way. With fuel expected to run out in 2018, I will discuss the closing Campaigns, highlight the final target selection opportunities, and explain the data archive and TESS-compatible software tools the K2 mission intends to leave behind for posterity.

Fe-12Ni-4Co-2Mo-.05Ti alloy for use at 77°K and below

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whitaker, Bradley Watford

A variant of the maraging class of steels is proposed for application at 77°K and below where a combination of very high strength and good toughness is required. The alloy has a composition of Fe-12Ni-4Co-2Mo-0.05Ti where low interstitial content. The as quenched and quenched and aged structures were completely martensitic with a prior austenitic grain size of 10 to 12 μm. This structure had a Y.S. of 138.5 ksi and 154 ksi before and after aging respectively. All aging was done at 444°C for 4 hours. The DBTT was shown to lie above 77°K as measured by C v testing.more » Based on dilatometric studies of the α $Yields$ γ and γ → α transformation temperatures a cycling treatment consisting of reportedly heating to above the A f temperature followed by a water quench was utilized to further reduce the prior γ grain size to approximately 4 to 6 μm. The structure was completely martensitic and possessed a Y.S. of 151 ksi at 77°K in the unaged condition with a Y.S./K IC ratio of 1.9 while the aged structure showed a Y.S. of 162 ksi with a Y.S./K IC ratio of 1.3. C v testing showed the DBTT to lie between 77°K and 4.2°K. Further grain refinement was accomplished by a 2 phase decomposition procedure which resulted in a grain size of 1 to 2 μm. The structure which contained decreasing amounts of austenite with temperature (3.0 percent at R.T. to 1.0 percent at 4.2°K) showed the best combination of strength and ductility at 4.2°K. A Y.S. of 205 ksi with a Y.S./K IC ratio of 0.84 was achieved before aging. The aged structure was brittle at 4.2°K with a Y.S. of 218 ksi and a Y.S./K IC ratio of 0.425.« less

Experimental oxygen potentials of U 1-yPr yO 2± x and thermodynamic assessment of the U-Pr-O system

DOE PAGES

McMurray, Jake W.; Silva, Chinthaka M.

2015-12-09

Thermogravimetric analysis (TGA) was used to determine the oxygen potentials of fluorite urania-praseodymia (U 1-yPr yO 2± x) solid solutions for y = 0.10 and 0.20 between 1000 and 1500 °C. A thermodynamic assessment of U-Pr-O system was performed using the CALPHAD (CALculation of PHAse Diagrams) method. Furthermore, the models well reproduce the TGA measurements and the computed phase relations are in good agreement with those proposed from an X-ray diffraction investigation.

Synthesis and characterization of polymer eight-coordinate (enH 2)[Y III(pdta)(H 2O)] 2·10H 2O as well as the interaction of [Y III(pdta)(H 2O)] 22- with BSA

NASA Astrophysics Data System (ADS)

Liu, Bin; Wang, Jun; Wang, Xin; Liu, Bing-Mi; He, Ling-Ling; Xu, Shu-Kun

2010-12-01

The eight-coordinate (enH 2)[Y III(pdta)(H 2O)] 2·10H 2O (en = ethylenediamine and H 4pdta = 1,3-propylenediamine- N, N, N', N'-tetraacetic acid) was synthesized, meanwhile its molecular and crystal structures were determined by single-crystal X-ray diffraction technology. The interaction between [Y III(pdta)(H 2O)] 22- and bovine serum albumin (BSA) was investigated by UV-vis and fluorescence spectra. The results indicate that [Y III(pdta)(H 2O)] 22- quenched effectively the intrinsic fluorescence of BSA via a static quenching process with the binding constant ( Ka) of the order of 10 4. Meanwhile, the binding and damaging sites to BSA molecules were also estimated by synchronous fluorescence. Results indicate that the hydrophobic environments around Trp and Tyr residues were all slightly changed. The thermodynamic parameters (Δ G = -25.20 kJ mol -1, Δ H = -26.57 kJ mol -1 and Δ S = -4.58 J mol -1 K -1) showed that the reaction was spontaneous and exothermic. What is more, both Δ H and Δ S were negative values indicated that hydrogen bond and Van der Waals forces were the predominant intermolecular forces between [Y III(pdta)(H 2O)] 22- and BSA.

De-Trending K2 Exoplanet Targets for High Spacecraft Motion

NASA Astrophysics Data System (ADS)

Saunders, Nicholas; Luger, Rodrigo; Barnes, Rory

2018-01-01

After the failure of two reaction wheels, the Kepler space telescope lost its fine pointing ability and entered a new phase of observation, K2. Targets observed by K2 have high motion relative to the detector and K2 light curves have higher noise than Kepler observations. Despite the increased noise, systematics removal pipelines such as K2SFF and EVEREST have enabled continued high-precision transiting planet science with the telescope, resulting in the detection of hundreds of new exoplanets. However, as the spacecraft begins to run out of fuel, sputtering will drive large and random variations in pointing that can prevent detection of exoplanets during the remaining 5 campaigns. In general, higher motion will spread the stellar point spread function (PSF) across more pixels during a campaign, which increases the number of degrees of freedom in the noise component and significantly reduces the de-trending power of traditional systematics removal methods. We use a model of the Kepler CCD combined with pixel-level information of a large number of stars across the detector to improve the performance of the EVEREST pipeline at high motion. We also consider the problem of increased crowding for static apertures in the high-motion regime and develop pixel response function (PRF)-fitting techniques to mitigate contamination and maximize the de-trending power. We assess the performance of our code by simulating sputtering events and assessing exoplanet detection efficiency with transit injection/recovery tests. We find that targets with roll amplitudes of up to 8 pixels, approximately 15 times K2 roll, can be de-trended within 2 to 3 factors of current K2 photometric precision for stars up to 14th magnitude. Achieved recovery precision allows detection of small planets around 11th and 12th magnitude stars. These methods can be applied to the light curves of K2 targets for existing and future campaigns to ensure that precision exoplanet science can still be performed

Dielectric Study of the Phase Transitions in [P(CH3)4]2CuY4 (Y = Cl, Br)

NASA Astrophysics Data System (ADS)

Gesi, Kazuo

2002-05-01

Phase transitions in [P(CH3)4]2CuY4 (Y = Cl, Br) have been studied by dielectric measurements. In [P(CH3)4]2CuCl4, a slight break and a discontinuous jump on the dielectric constant vs. temperature curve are seen at the normal-incommensurate and the incommensurate-commensurate phase transitions, respectively. A small peak of dielectric constant along the b-direction exists just above the incommensurate-to-commensurate transition temperature. The anisotropic dielectric anomalies of [P(CH3)4]2CuBr4 at phase transitions were measured along the three crystallographic axes. The pressure-temperature phase diagram of [P(CH3)4]2CuCl4 was determined. The initial pressure coefficients of the normal-to-incommensurate and the incommensurate-to-commensurate transition temperatures are 0.19 K/MPa and 0.27 K/MPa, respectively. The incommensurate phase in [P(CH3)4]2CuCl4 disappears at a triple point which exists at 335 MPa and 443 K. The stability and the pressure effects of the incommensurate phases are much different among the four [Z(CH3)4]2CuY4 crystals (Z = N, P; Y = Cl, Br).

Synthesis of [(Ca1-xSrx)2-2y](Ti2-2yLi2y)Si2yO6-y Ceramic and its Application in Efficient Plasma Decomposition of CO2

NASA Astrophysics Data System (ADS)

Li, Ruixing; Tang, Qing; Yin, Shu; Sato, Tsugio

According to both the first principle and materials chemistry, a method for fabricating [(Ca1-xSrx)2-2y](Ti2-2yLi2y)Si2yO6-y ceramic was investigated. It was considered that the sintering was promoted by self-accelerated diffusion due to the formation of point defects caused by doping with Li2Si2O5. Consequently, a concept of non-stoichiometrically activated sintering, which was enhanced by point defects without the help of a grain boundary phase, was systematically studied in the Ca1-xSrxTiO3-Li2Si2O5 system. The mechanical and dielectric properties of [(Ca1-xSrx)2-2y](Ti2-2yLi2y)Si2yO6-y were greatly enhanced by adding Li2Si2O5. To improve CO2 decomposition activity, [(Ca1-xSrx)2-2y](Ti2-2yLi2y)Si2yO6-y, which possesses both high permittivity and high dielectric strength was used as a dielectric barrier to decompose CO2 by dielectric barrier discharges (DBDs) plasma without using any catalyst and auxiliary substance. It successfully generated DBDs plasma and the CO2 conversion was much higher than that using an alumina or a silica glass barrier which was widely used as the dielectric barrier in previous studies.

2. Historic American Buildings Survey Frank O. Branzetti, Photographer Aug. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. Historic American Buildings Survey Frank O. Branzetti, Photographer Aug. 6, 1940 (y) 3- MILE STONE, 45 CENTRE ST., ROXBURY - Milestones D, Y, Z, AA, BB, FF & NN, Various Roxbury locations, Roxbury, Suffolk County, MA

Survey of K-3rd-Grade Teachers' Knowledge of Ear Infections and Willingness to Participate in Prevention Programs

ERIC Educational Resources Information Center

Danhauer, Jeffrey L.; Johnson, Carole E.; Caudle, Abby T.

2011-01-01

Purpose: Ear infections are prevalent in kindergarten through 3rd-grade (K-3rd) children and can affect their performance at school. Chewing gum, when administered by parents and teachers, can help prevent ear infections in children. This pilot study surveyed K-3rd-grade teachers in the Santa Barbara School Districts to assess their knowledge…

Properties of spin-1/2 triangular-lattice antiferromagnets CuY2Ge2O8 and CuLa2Ge2O8

NASA Astrophysics Data System (ADS)

Cho, Hwanbeom; Kratochvílová, Marie; Sim, Hasung; Choi, Ki-Young; Kim, Choong Hyun; Paulsen, Carley; Avdeev, Maxim; Peets, Darren C.; Jo, Younghun; Lee, Sanghyun; Noda, Yukio; Lawler, Michael J.; Park, Je-Geun

2017-04-01

We found new two-dimensional (2D) quantum (S =1 /2 ) antiferromagnetic systems: Cu R E2G e2O8 (R E =Y and La). According to our analysis of high-resolution x-ray and neutron diffraction experiments, the Cu network of Cu R E2G e2O8 (R E =Y and La) exhibits a 2D triangular lattice linked via weak bonds along the perpendicular b axis. Our bulk characterizations from 0.08 to 400 K show that they undergo a long-range order at 0.51(1) and 1.09(4) K for the Y and La systems, respectively. Interestingly, they also exhibit field induced phase transitions. For theoretical understanding, we carried out the density functional theory (DFT) band calculations to find that they are typical charge-transfer-type insulators with a gap of Eg≅2 eV . Taken together, our observations make Cu R E2G e2O8 (R E =Y and La) additional examples of low-dimensional quantum spin triangular antiferromagnets with the low-temperature magnetic ordering.

A magnetic topological semimetal Sr 1-yMn 1-zSb2 (y, z < 0.10)

DOE PAGES

Liu, J. Y.; Hu, J.; Zhang, Qiang; ...

2017-07-24

Weyl (WSMs) evolve from Dirac semimetals in the presence of broken time-reversal symmetry (TRS) or space-inversion symmetry. The WSM phases in TaAs-class materials and photonic crystals are due to the loss of space-inversion symmetry. For TRS-breaking WSMs, despite numerous theoretical and experimental efforts, few examples have been reported. Here in this paper, we report a new type of magnetic semimetal Sr 1-yMn 1-zSb 2 (y, z < 0.1) with nearly massless relativistic fermion behaviour (m* = 0.04 - 0.05m 0, where m 0 is the free-electron mass). This material exhibits a ferromagnetic order for 304 K < T < 565more » K, but a canted antiferromagnetic order with a ferromagnetic component for T < 304 K. The combination of relativistic fermion behaviour and ferromagnetism in Sr 1-yMn 1-zSb2 offers a rare opportunity to investigate the interplay between relativistic fermions and spontaneous TRS breaking.« less

A magnetic topological semimetal Sr 1-yMn 1-zSb2 (y, z < 0.10)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, J. Y.; Hu, J.; Zhang, Qiang

Weyl (WSMs) evolve from Dirac semimetals in the presence of broken time-reversal symmetry (TRS) or space-inversion symmetry. The WSM phases in TaAs-class materials and photonic crystals are due to the loss of space-inversion symmetry. For TRS-breaking WSMs, despite numerous theoretical and experimental efforts, few examples have been reported. Here in this paper, we report a new type of magnetic semimetal Sr 1-yMn 1-zSb 2 (y, z < 0.1) with nearly massless relativistic fermion behaviour (m* = 0.04 - 0.05m 0, where m 0 is the free-electron mass). This material exhibits a ferromagnetic order for 304 K < T < 565more » K, but a canted antiferromagnetic order with a ferromagnetic component for T < 304 K. The combination of relativistic fermion behaviour and ferromagnetism in Sr 1-yMn 1-zSb2 offers a rare opportunity to investigate the interplay between relativistic fermions and spontaneous TRS breaking.« less

The Northern Marshall Islands Radiological Survey: data and dose assessments.

PubMed

Robison, W L; Noshkin, V E; Conrado, C L; Eagle, R J; Brunk, J L; Jokela, T A; Mount, M E; Phillips, W A; Stoker, A C; Stuart, M L; Wong, K M

1997-07-01

Fallout from atmospheric nuclear tests, especially from those conducted at the Pacific Proving Grounds between 1946 and 1958, contaminated areas of the Northern Marshall Islands. A radiological survey at some Northern Marshall Islands was conducted from September through November 1978 to evaluate the extent of residual radioactive contamination. The atolls included in the Northern Marshall Islands Radiological Survey (NMIRS) were Likiep, Ailuk, Utirik, Wotho, Ujelang, Taka, Rongelap, Rongerik, Bikar, Ailinginae, and Mejit and Jemo Islands. The original test sites, Bikini and Enewetak Atolls, were also visited on the survey. An aerial survey was conducted to determine the external gamma exposure rate. Terrestrial (soil, food crops, animals, and native vegetation), cistern and well water samples, and marine (sediment, seawater, fish and clams) samples were collected to evaluate radionuclide concentrations in the atoll environment. Samples were processed and analyzed for 137Cs, 90Sr, 239+240Pu and 241Am. The dose from the ingestion pathway was calculated using the radionuclide concentration data and a diet model for local food, marine, and water consumption. The ingestion pathway contributes 70% to 90% of the estimated dose. Approximately 95% of the dose is from 137Cs. 90Sr is the second most significant radionuclide via ingestion. External gamma exposure from 137Cs accounts for about 10% to 30% of the dose. 239+240Pu and 241Am are the major contributors to dose via the inhalation pathway; however, inhalation accounts for only about 1% of the total estimated dose, based on surface soil levels and resuspension studies. All doses are computed for concentrations decay corrected to 1996. The maximum annual effective dose from manmade radionuclides at these atolls ranges from .02 mSv y(-1) to 2.1 mSv y(-1). The background dose in the Marshall Islands is estimated to be 2.4 mSv y(-1). The combined dose from both background and bomb related radionuclides ranges from slightly

Vitamin K2 suppresses rotenone-induced microglial activation in vitro

PubMed Central

Yu, Yan-xia; Li, Yi-pei; Gao, Feng; Hu, Qing-song; Zhang, Yan; Chen, Dong; Wang, Guang-hui

2016-01-01

Aim: Increasing evidence has shown that environmental factors such as rotenone and paraquat induce neuroinflammation, which contributes to the pathogenesis of Parkinson's disease (PD). In this study, we investigated the molecular mechanisms underlying the repression by menaquinone-4 (MK-4), a subtype of vitamin K2, of rotenone-induced microglial activation in vitro. Methods: A microglial cell line (BV2) was exposed to rotenone (1 μmol/L) with or without MK-4 treatment. The levels of TNF-α or IL-1β in 100 μL of cultured media of BV2 cells were measured using ELISA kits. BV2 cells treated with rotenone with or without MK4 were subjected to mitochondrial membrane potential, ROS production, immunofluorescence or immunoblot assays. The neuroblastoma SH-SY5Y cells were treated with conditioned media (CM) of BV2 cells that were exposed to rotenone with or without MK-4 treatment, and the cell viability was assessed using MTT assay. Results: In rotenone-treated BV2 cells, MK-4 (0.5–20 μmol/L) dose-dependently suppressed the upregulation in the expression of iNOS and COX-2 in the cells, as well as the production of TNF-α and IL-1β in the cultured media. MK-4 (5–20 μmol/L) significantly inhibited rotenone-induced nuclear translocation of NF-κB in BV2 cells. MK-4 (5–20 μmol/L) significantly inhibited rotenone-induced p38 activation, ROS production, and caspase-1 activation in BV2 cells. MK-4 (5–20 μmol/L) also restored the mitochondrial membrane potential that had been damaged by rotenone. Exposure to CM from rotenone-treated BV2 cells markedly decreased the viability of SH-SY5Y cells. However, this rotenone-activated microglia-mediated death of SH-SY5Y cells was significantly attenuated when the BV2 cells were co-treated with MK-4 (5–20 μmol/L). Conclusion: Vitamin K2 can directly suppress rotenone-induced activation of microglial BV2 cells in vitro by repressing ROS production and p38 activation. PMID:27498777

Synthesis of the (N2)3- radical from Y2+ and its protonolysis reactivity to form (N2H2)2- via the Y[N(SiMe3)2]3/KC8 reduction system.

PubMed

Fang, Ming; Lee, David S; Ziller, Joseph W; Doedens, Robert J; Bates, Jefferson E; Furche, Filipp; Evans, William J

2011-03-23

Examination of the Y[N(SiMe(3))(2)](3)/KC(8) reduction system that allowed isolation of the (N(2))(3-) radical has led to the first evidence of Y(2+) in solution. The deep-blue solutions obtained from Y[N(SiMe(3))(2)](3) and KC(8) in THF at -35 °C under argon have EPR spectra containing a doublet at g(iso) = 1.976 with a 110 G hyperfine coupling constant. The solutions react with N(2) to generate (N(2))(2-) and (N(2))(3-) complexes {[(Me(3)Si)(2)N](2)(THF)Y}(2)(μ-η(2):η(2)-N(2)) (1) and {[(Me(3)Si)(2)N](2)(THF)Y}(2)(μ-η(2):η(2)-N(2))[K(THF)(6)] (2), respectively, and demonstrate that the Y[N(SiMe(3))(2)](3)/KC(8) reaction can proceed through an Y(2+) intermediate. The reactivity of (N(2))(3-) radical with proton sources was probed for the first time for comparison with the (N(2))(2-) and (N(2))(4-) chemistry. Complex 2 reacts with [Et(3)NH][BPh(4)] to form {[(Me(3)Si)(2)N](2)(THF)Y}(2)(μ-N(2)H(2)), the first lanthanide (N(2)H(2))(2-) complex derived from dinitrogen, as well as 1 as a byproduct, consistent with radical disproportionation reactivity.

Decision support model for assessing archaeological survey needs for bridge replacement projects in Iowa.

DOT National Transportation Integrated Search

2006-01-01

The Bridges Decision Support Model is a geographic information system (GIS) that assembles existing : data on archaeological sites, surveys, and their geologic contexts to assess the risk of bridge replacement : projects encountering 13,000- to 150-y...

Anti-H-Y responses of H-2b mutant mice.

PubMed

Simpson, E; Gordon, R D; Chandler, P R; Bailey, D

1978-10-01

Two strains of H-2b mutant mice, H-2ba and H-2bf, in which the mutational event took place at H-2K, make anti-H-Y cytotoxic T cell responses which are H-2-restricted, Db-associated and indistinguishable in target cell specificity from those of H-2b mice. Thus, alteration of the H-2K molecule affects neither the Ir gene controlling the response, nor the associative antigen. On the other hand, one H-2Db mutant strain, H-2bo, although it makes a good anti-H-Y cytotoxic response, shows target cell specificity restricted to its own Dbo antigen(s), and neither H-2b, H-2ba or H-2bf anti-H-Y cytotoxic cells kill H-2bo male target cells. Thus, the alteration of the H-2Db molecule does not affect the Ir gene of H-2b mice, but it does alter the H-2Db-associative antigen.

Giant increase of critical current density and vortex pinning in Mn doped K{sub x}Fe{sub 2−y}Se{sub 2} single crystals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Mingtao; Zhang, Jincang, E-mail: jczhang@staff.shu.edu.cn; Materials Genome Institute, Shanghai University, Shanghai 200444

2014-11-10

We report a comparative study of the critical current density (J{sub c}) and vortex pinning among pure and Mn doped K{sub x}Fe{sub 2−y}Se{sub 2} single crystals. It is found that the J{sub c} values can be greatly improved by Mn doping and post-quenching treatment when comparing to pristine pure sample. In contrast to pure samples, an anomalous second magnetization peak (SMP) effect is observed in both 1% and 2% Mn doped samples at T = 3 K for H∥ab but not for H∥c. Referring to Dew-Hughes and Kramer's model, we performed scaling analyses of the vortex pinning force density vs magnetic field inmore » 1% Mn doped and quenched pristine crystals. The results show that the normal point defects are the dominant pinning sources, which probably originate from the variations of intercalated K atoms. We propose that the large nonsuperconducting K-Mn-Se inclusions may contribute to the partial normal surface pinning and give rise to the anomalous SMP effect for H∥ab in Mn doped crystals. These results may facilitate further understanding of the superconductivity and vortex pinning in intercalated iron-selenides superconductors.« less

Energetics of the O-H bond and of intramolecular hydrogen bonding in HOC6H4C(O)Y (Y = H, CH3, CH2CH=CH2, C[triple bond]CH, CH2F, NH2, NHCH3, NO2, OH, OCH3, OCN, CN, F, Cl, SH, and SCH3) compounds.

PubMed

Bernardes, Carlos E S; Minas da Piedade, Manuel E

2008-10-09

The energetics of the phenolic O-H bond in a series of 2- and 4-HOC 6H 4C(O)Y (Y = H, CH3, CH 2CH=CH2, C[triple bond]CH, CH2F, NH2, NHCH 3, NO2, OH, OCH3, OCN, CN, F, Cl, SH, and SCH3) compounds and of the intramolecular O...H hydrogen bond in 2-HOC 6H 4C(O)Y, was investigated by using a combination of experimental and theoretical methods. The standard molar enthalpies of formation of 2-hydroxybenzaldehyde (2HBA), 4-hydroxybenzaldehyde (4HBA), 2'-hydroxyacetophenone (2HAP), 2-hydroxybenzamide (2HBM), and 4-hydroxybenzamide (4HBM), at 298.15 K, were determined by micro- or macrocombustion calorimetry. The corresponding enthalpies of vaporization or sublimation were also measured by Calvet drop-calorimetry and Knudsen effusion measurements. The combination of the obtained experimental data led to Delta f H m (o)(2HBA, g) = -238.3 +/- 2.5 kJ.mol (-1), DeltafHm(o)(4HBA, g) = -220.3 +/- 2.0 kJ.mol(-1), Delta f H m (o)(2HAP, g) = -291.8 +/- 2.1 kJ.mol(-1), DeltafHm(o)(2HBM, g) = -304.8 +/- 1.5 kJ.mol (-1), and DeltafHm(o) (4HBM, g) = -278.4 +/- 2.4 kJ.mol (-1). These values, were used to assess the predictions of the B3LYP/6-31G(d,p), B3LYP/6-311+G(d,p), B3LYP/aug-cc-pVDZ, B3P86/6-31G(d,p), B3P86/6-311+G(d,p), B3P86/aug-cc-pVDZ, and CBS-QB3 methods, for the enthalpies of a series of isodesmic gas phase reactions. In general, the CBS-QB3 method was able to reproduce the experimental enthalpies of reaction within their uncertainties. The B3LYP/6-311+G(d,p) method, with a slightly poorer accuracy than the CBS-QB3 approach, achieved the best performance of the tested DFT models. It was further used to analyze the trends of the intramolecular O...H hydrogen bond in 2-HOC 6H 4C(O)Y evaluated by the ortho-para method and to compare the energetics of the phenolic O-H bond in 2- and 4-HOC 6H 4C(O)Y compounds. It was concluded that the O-H bond "strength" is systematically larger for 2-hydroxybenzoyl than for the corresponding 4-hydroxybenzoyl isomers mainly due to the presence of

139La and 63Cu NMR investigation of charge order in La2CuO4 +y (Tc=42 K)

NASA Astrophysics Data System (ADS)

Imai, T.; Lee, Y. S.

2018-03-01

We report 139La and 63Cu NMR investigation of the successive charge order, spin order, and superconducting transitions in superoxygenated La2CuO4 +y single crystal with stage-4 excess oxygen order at Tstage≃290 K. We show that the stage-4 order induces tilting of CuO6 octahedra below Tstage, which in turn causes 139La NMR line broadening. The structural distortion continues to develop far below Tstage, and completes at Tcharge≃60 K, where charge order sets in. This sequence is reminiscent of the the charge-order transition in Nd codoped La1.88Sr0.12CuO4 that sets in once the low-temperature tetragonal phase is established. We also show that the paramagnetic 63Cu NMR signals are progressively wiped out below Tcharge due to enhanced low-frequency spin fluctuations in charge-ordered domains, but the residual 63Cu NMR signals continue to exhibit the characteristics expected for optimally doped superconducting CuO2 planes. This indicates that charge order in La2CuO4 +y does not take place uniformly in space. In addition, unlike the typical second-order magnetic phase transitions, low-frequency Cu spin fluctuations as probed by 139La nuclear spin-lattice relaxation rate do not exhibit critical divergence at Tspin(≃Tc ) =42 K. These findings, including the spatially inhomogeneous nature of the charge-ordered state, are qualitatively similar to the case of La1.885Sr0.115CuO4 [Imai et al., Phys. Rev. B 96, 224508 (2017), 10.1103/PhysRevB.96.224508 and Arsenault et al., Phys. Rev. B 97, 064511 (2018), 10.1103/PhysRevB.97.064511], but both charge and spin order take place more sharply in the present case.

Synthetic and spectroscopic studies of vanadate glaserites II: Photoluminescence studies of Ln:K{sub 3}Y(VO{sub 4}){sub 2} (Ln=Eu, Er, Sm, Ho, or Tm)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kimani, Martin M., E-mail: kimani@g.clemson.edu; McMillen, Colin D., E-mail: cmcmill@g.clemson.edu; Kolis, Joseph W., E-mail: kjoseph@clemson.edu

2015-03-15

Glaserite-type potassium yttrium double vanadates (K{sub 3}Y(VO{sub 4}){sub 2}) doped with Eu{sup 3+}, Er{sup 3+}, Sm{sup 3+}, Ho{sup 3+}, or Tm{sup 3+} have been synthesized by solid state reactions at 1000 °C for 48 h and their photoluminescence properties investigated. Efficient energy transfer from the vanadate group to the rare earth ion has been established by photoluminescence investigation. Ultraviolet excitation into the metal to ligand charge transfer band of the vanadate groups results in orange-red, blue and green emissions from Eu{sup 3+} (592 nm), Sm{sup 3+} (602 nm), Tm{sup 3+} (475 nm), Er{sup 3+} (553 nm), and Ho{sup 3+} (541–551more » nm) dopant ions. The emission intensities of the lanthanide-doped K{sub 3}Y(VO{sub 4}){sub 2} powders were studied as a function of dopant ion concentrations. Over the concentration ranges studied, no emission quenching was observed for Eu{sup 3+} or Ho{sup 3+} dopants, while Er{sup 3+}, Sm{sup 3+} and Tm{sup 3+} dopants did exhibit such effects for dopant ion concentrations greater than 5%, probably due to cross relaxation processes. - Graphical abstract: Synthesis and photoluminescence in vanadate glaserites. - Highlights: • K{sub 3}Y(VO{sub 4}){sub 2} doped with Eu, Er, Tm, Sm, or Ho were synthesized via solid-state reactions. • Photoluminescence properties are investigated. • The lanthanide doped K{sub 3}Y(VO{sub 4}){sub 2} compounds revealed efficient energy transfer from the vanadate group to the rare earth ions. • The presented compounds are promising materials for light display systems, lasers, and optoelectronic devices.« less

Simulated JWST/NIRISS Spectroscopy of Anticipated TESS Planets and Selected Super-Earths Discovered from K2 and Ground-Based Surveys

NASA Astrophysics Data System (ADS)

Louie, Dana; Albert, Loic; Deming, Drake

2017-01-01

The 2018 launch of James Webb Space Telescope (JWST), coupled with the 2017 launch of the Transiting Exoplanet Survey Satellite (TESS), heralds a new era in Exoplanet Science, with TESS projected to detect over one thousand transiting sub-Neptune-sized planets (Ricker et al, 2014), and JWST offering unprecedented spectroscopic capabilities. Sullivan et al (2015) used Monte Carlo simulations to predict the properties of the planets that TESS is likely to detect, and published a catalog of 962 simulated TESS planets. Prior to TESS launch, the re-scoped Kepler K2 mission and ground-based surveys such as MEarth continue to seek nearby Earth-like exoplanets orbiting M-dwarf host stars. The exoplanet community will undoubtedly employ JWST for atmospheric characterization follow-up studies of promising exoplanets, but the targeted planets for these studies must be chosen wisely to maximize JWST science return. The goal of this project is to estimate the capabilities of JWST’s Near InfraRed Imager and Slitless Spectrograph (NIRISS)—operating with the GR700XD grism in Single Object Slitless Spectrography (SOSS) mode—during observations of exoplanets transiting their host stars. We compare results obtained for the simulated TESS planets, confirmed K2-discovered super-Earths, and exoplanets discovered using ground-based surveys. By determining the target planet characteristics that result in the most favorable JWST observing conditions, we can optimize the choice of target planets in future JWST follow-on atmospheric characterization studies.

omega-Amino acid:pyruvate transaminase from Alcaligenes denitrificans Y2k-2: a new catalyst for kinetic resolution of beta-amino acids and amines.

PubMed

Yun, Hyungdon; Lim, Seongyop; Cho, Byung-Kwan; Kim, Byung-Gee

2004-04-01

Alcaligenes denitrificans Y2k-2 was obtained by selective enrichment followed by screening from soil samples, which showed omega-amino acid:pyruvate transaminase activity, to kinetically resolve aliphatic beta-amino acid, and the corresponding structural gene (aptA) was cloned. The gene was functionally expressed in Escherichia coli BL21 by using an isopropyl-beta-D-thiogalactopyranoside (IPTG)-inducible pET expression system (9.6 U/mg), and the recombinant AptA was purified to show a specific activity of 77.2 U/mg for L-beta-amino-n-butyric acid (L-beta-ABA). The enzyme converts various beta-amino acids and amines to the corresponding beta-keto acids and ketones by using pyruvate as an amine acceptor. The apparent K(m) and V(max) for L-beta-ABA were 56 mM and 500 U/mg, respectively, in the presence of 10 mM pyruvate. In the presence of 10 mM L-beta-ABA, the apparent K(m) and V(max) for pyruvate were 11 mM and 370 U/mg, respectively. The enzyme exhibits high stereoselectivity (E > 80) in the kinetic resolution of 50 mM D,L-beta-ABA, producing optically pure D-beta-ABA (99% enantiomeric excess) with 53% conversion.

K2-EDTA and K3-EDTA Greiner Tubes for HbA1c Measurement.

PubMed

Vrtaric, Alen; Filipi, Petra; Hemar, Marina; Nikolac, Nora; Simundic, Ana-Maria

2016-02-01

To determine whether K2-ethylenediaminetetraacetic acid (EDTA) and K3-EDTA Greiner tubes could be used interchangeably for glycosylated hemoglobin, type A1C (HbA1c) measurement via the Abbott Laboratories ARCHITECT chemiluminescent microparticle HbA1c assay on the ARCHITECT i2000SR immunoanalyzer at our university hospital. We drew blood from a total of 45 outpatients into plastic Greiner Vacuette tubes, some of which were lined with K2-EDTA and others with K3-EDTA anticoagulant. Data are presented as median and interquartile range values. We used the Wilcoxon test and Passing-Bablok regression for tube comparison. For K2-EDTA tubes median HbA1c concentration was 54 mmol/mol (41 to 71 mmol/mol) and for K3-EDTA tubes 56 mmol/mol (43 to 69 mmol/mol). There was no statistically significant difference between K2-EDTA and K3-EDTA (bias= -1.29 mmol/mol; P = 0.24). Passing-Bablok regression showed that there is no constant and proportional error: y = -0.23 (95% CI[-3.52 to 0.69]) + 1.00( 95% CI[0.98 to 1.06]) x. In this study, we provide evidence for the lack of any clinically and statistically significant bias between K2-EDTA and K3-EDTA HbA1c measurements. Thus, Greiner tubes lined with K2-EDTA and those lined with K3-EDTA can safely be used interchangeably to measure HbA1c via the Abbott Laboratories ARCHITECT assay. © American Society for Clinical Pathology, 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

La 139 and Cu 63 NMR investigation of charge order in La 2 CuO 4 + y ( T c = 42 K)

DOE PAGES

Imai, T.; Lee, Y. S.

2018-03-14

Here, we report 139La and 63Cu NMR investigation of the successive charge order, spin order, and superconducting transitions in superoxygenated La 2CuO 4+y single crystal with stage-4 excess oxygen order at T stage≃290 K. We show that the stage-4 order induces tilting of CuO 6 octahedra below T stage, which in turn causes 139La NMR line broadening. The structural distortion continues to develop far below Tstage, and completes at T charge≃60 K, where charge order sets in. This sequence is reminiscent of the the charge-order transition in Nd codoped La 1.88Sr 0.12CuO 4 that sets in once the low-temperature tetragonalmore » phase is established. We also show that the paramagnetic 63Cu NMR signals are progressively wiped out below T charge due to enhanced low-frequency spin fluctuations in charge-ordered domains, but the residual 63Cu NMR signals continue to exhibit the characteristics expected for optimally doped superconducting CuO 2 planes. This indicates that charge order in La 2CuO 4+y does not take place uniformly in space. In addition, unlike the typical second-order magnetic phase transitions, low-frequency Cu spin fluctuations as probed by 139La nuclear spin-lattice relaxation rate do not exhibit critical divergence at T spin(≃T c) =42 K. These findings, including the spatially inhomogeneous nature of the charge-ordered state, are qualitatively similar to the case of La 1.885Sr 0.115CuO 4, but both charge and spin order take place more sharply in the present case.« less

La 139 and Cu 63 NMR investigation of charge order in La 2 CuO 4 + y ( T c = 42 K)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Imai, T.; Lee, Y. S.

Here, we report 139La and 63Cu NMR investigation of the successive charge order, spin order, and superconducting transitions in superoxygenated La 2CuO 4+y single crystal with stage-4 excess oxygen order at T stage≃290 K. We show that the stage-4 order induces tilting of CuO 6 octahedra below T stage, which in turn causes 139La NMR line broadening. The structural distortion continues to develop far below Tstage, and completes at T charge≃60 K, where charge order sets in. This sequence is reminiscent of the the charge-order transition in Nd codoped La 1.88Sr 0.12CuO 4 that sets in once the low-temperature tetragonalmore » phase is established. We also show that the paramagnetic 63Cu NMR signals are progressively wiped out below T charge due to enhanced low-frequency spin fluctuations in charge-ordered domains, but the residual 63Cu NMR signals continue to exhibit the characteristics expected for optimally doped superconducting CuO 2 planes. This indicates that charge order in La 2CuO 4+y does not take place uniformly in space. In addition, unlike the typical second-order magnetic phase transitions, low-frequency Cu spin fluctuations as probed by 139La nuclear spin-lattice relaxation rate do not exhibit critical divergence at T spin(≃T c) =42 K. These findings, including the spatially inhomogeneous nature of the charge-ordered state, are qualitatively similar to the case of La 1.885Sr 0.115CuO 4, but both charge and spin order take place more sharply in the present case.« less

Tier 2 Reading Interventions, K-2nd Grade Practices and Processes

ERIC Educational Resources Information Center

Allison, Tamara Alice

2016-01-01

Due to variation that exists in providing Tier 2 reading intervention instruction, the purpose of the study was to identify processes and instructional strategies currently being utilized by K-2 teachers of the Gallup, New Mexico elementary schools. 17 teachers from 9 of the 10 elementary schools participated in the study. A survey instrument was…

Phase diagram of the Y–Y{sub 2}Se{sub 3} system, enthalpies of phase transformations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andreev, O.V.; Kharitontsev, V.B.; Polkovnikov, A.A., E-mail: a.a.polkovnikov@yandex.ru

A phase diagram for the Y–Y{sub 2}Se{sub 3} system has been constructed in which the YSe and Y{sub 2}Se{sub 3} phases melt congruently. The daltonide type YSe phase (ST Y{sub 0,75}Se, a=1.1393 nm, melting point=2380 K, H=2200 MPa) forms a double-sided solid solution from 49–50–53 at% Se. In the 50–53 at% Se range, the unit cell parameter increases to 1.1500 nm, the microhardness increases to 4100 MPa and electrical resistivity increases from 0.018 to 0.114 Ω m. These changes are caused by the dominating influx of newly formed structural cationic vacancies arising from the selenium anions that are surplus formore » the 1:1 Y:Se stoichiometry. The full-valence Y{sub 2}Se{sub 3} composition exists as a low-temperature modification of ε-Y{sub 2}Se{sub 3} (ST Sc{sub 2}S{sub 3}, a=1.145 nm, b=0.818 nm, c=2.438 nm, melting point=1780 K, ∆fusion enthalpy=4±0.4 J/g) and transforms into a modification of ξ-Y{sub 2}Se{sub 3} that does not undergo fixing by thermo-hardening. The eutectic melting point between the YSe and Y{sub 2}Se{sub 3} phases is 1625±5 K, with a eutectic composition that is assumed to be 57.5 at% Se and have an enthalpy of fusion of 43±4.3 J/g. The eutectic for the Y and YSe phases appears at a temperature of 1600 K and 5 at% Se. - Highlights: • Phase equilibria in the Y–Y{sub 2}Se{sub 3} system from 1000 K to melt were studies. • High-temperature polymorphic transition for Y{sub 2}Se{sub 3} were observed. • Singular points in solid solutions areas for YSe and Y{sub 2}Se{sub 3} were found.« less

(Cu 0.5Tl 0.5)Ba 2Ca n-1 Cu n- yGe yO 2 n+4- δ ( n = 3, 4 and y = 0.5, 0.75, 1.0); superconductors with GeO 2 planes

NASA Astrophysics Data System (ADS)

Khan, Nawazish A.; Irfan, M.

2008-12-01

We have successfully synthesized germanium doped (Cu 0.5Tl 0.5)Ba 2Ca n-1 Cu n- yGe yO 2 n+4- δ ( n = 3, 4 and y = 0, 0.5, 0.75, 1.0) superconductors and investigated the effect of Ge doping on the superconducting properties of these compounds. The solubility of Ge till y = 1 in the CuO 2 planes of (Cu 0.5Tl 0.5)Ba 2Ca 2Cu 3- yGe yO 10- δ, have been found to give superconductivity above 77 K. To our surprise an enhanced superconductivity is observed with the doping of semiconductor germanium in some samples. The enhanced superconductivity associated with mixed CuO 2/GeO 2 planes can be extremely useful for the understanding of mechanism of superconductivity; since we very well know the properties of germanium based semiconductors.

Magnetic dilution and domain selection in the X Y pyrochlore antiferromagnet Er2Ti2O7

NASA Astrophysics Data System (ADS)

Gaudet, J.; Hallas, A. M.; Maharaj, D. D.; Buhariwalla, C. R. C.; Kermarrec, E.; Butch, N. P.; Munsie, T. J. S.; Dabkowska, H. A.; Luke, G. M.; Gaulin, B. D.

2016-08-01

Below TN=1.1 K, the X Y pyrochlore Er2Ti2O7 orders into a k =0 noncollinear, antiferromagnetic structure referred to as the ψ2 state. The magnetic order in Er2Ti2O7 is known to obey conventional three-dimensional (3D) percolation in the presence of magnetic dilution, and in that sense is robust to disorder. Recently, however, two theoretical studies have predicted that the ψ2 structure should be unstable to the formation of a related ψ3 magnetic structure in the presence of magnetic vacancies. To investigate these theories, we have carried out systematic elastic and inelastic neutron scattering studies of three single crystals of Er2 -xYxTi2O7 with x =0 (pure), 0.2 (10 %Y ) and 0.4 (20 % Y ), where magnetic Er3 + is substituted by nonmagnetic Y3 +. We find that the ψ2 ground state of pure Er2Ti2O7 is significantly affected by magnetic dilution. The characteristic domain selection associated with the ψ2 state, and the corresponding energy gap separating ψ2 from ψ3, vanish for Y3 + substitutions between 10 % Y and 20 % Y , far removed from the three-dimensional percolation threshold of ˜60 % Y . The resulting ground state for Er2Ti2O7 with magnetic dilutions from 20 % Y up to the percolation threshold is naturally interpreted as a frozen mosaic of ψ2 and ψ3 domains.

Diffractive elements for generating microscale laser beam patterns: a Y2K problem

NASA Astrophysics Data System (ADS)

Teiwes, Stephan; Krueger, Sven; Wernicke, Guenther K.; Ferstl, Margit

2000-03-01

Lasers are widely used in industrial fabrication for engraving, cutting and many other purposes. However, material processing at very small scales is still a matter of concern. Advances in diffractive optics could provide for laser systems that could be used for engraving or cutting of micro-scale patterns at high speeds. In our paper we focus on the design of diffractive elements which can be used for this special application. It is a common desire in material processing to apply 'discrete' as well as 'continuous' beam patterns. Especially, the latter case is difficult to handle as typical micro-scale patterns are characterized by bad band-limitation properties, and as speckles can easily occur in beam patterns. It is shown in this paper that a standard iterative design method usually fails to obtain diffractive elements that generate diffraction patterns with acceptable quality. Insights gained from an analysis of the design problems are used to optimize the iterative design method. We demonstrate applicability and success of our approach by the design of diffractive phase elements that generate a discrete and a continuous 'Y2K' pattern.

Effects of addition of Bi2Ca2Co2O y on the thermoelectric properties of Ca3Co4O9 polycrystalline ceramics

NASA Astrophysics Data System (ADS)

Feng, Ningbo; Liao, Y. W.; Lu, Y.; He, Y.; Jin, Y. R.; Liu, X. R.

2018-06-01

Thermoelectric properties of Ca3Co4O9 polycrystalline ceramics with sheet grains were optimized by adding Bi2Ca2Co2O y phase. Therefore, the (1 - x) Ca3Co4O9/ x Bi2Ca2Co2O y (0 ≤ x ≤ 1) composites were prepared. The phase constitution and micro-structure of the samples were analyzed by XRD and SEM, respectively. With the addition of Bi2Ca2Co2O y , the apparent density D a and the relative density D r of the samples continuously increases. When x ≤ 0.4, the electrical resistivity of the samples declines, however, when x ≥ 0.4, the electrical resistivity of the samples increases. The Seebeck coefficient of the samples grows with the increase of the x monotonously. The power factor of the 0.6 Ca3Co4O9/0.4 Bi2Ca2Co2O y samples reaches 0.24 mW m-1K-2 at 973 K. Thermal conductivity κ of the 0.6 Ca3Co4O9/0.4 Bi2Ca2Co2O y monotonously decreases with the temperature rising, achieving the minimum about 1.34 W m-1K-1 at 973 K. The ZT of 0.6 Ca3Co4O9/0.4 Bi2Ca2Co2O y composites gets to 0.18, which is comparable to that of most doped Ca3Co4O9 polycrystalline ceramics, implying higher ZT can be realized by combining the strategy of doping and introducing the Bi2Ca2Co2O y .

Trends in Current Issues, Y2K-2005

ERIC Educational Resources Information Center

Maltz, Leslie; DeBlois, Peter B.

2005-01-01

EDUCAUSE inaugurated its annual Current Issues Survey in 2000 by asking the primary representatives, typically CIOs, of its member institutions to identify up to three critical IT issues (five starting in 2004) from among 30 to 40 in response to each of four questions. The survey response rate has typically been 35 to 40 percent, with a…

VizieR Online Data Catalog: UKIDSS-DR7 Large Area Survey (Lawrence+ 2011)

NASA Astrophysics Data System (ADS)

UKIDSS Consortium

2012-03-01

The UKIRT Infrared Deep Sky Survey (UKIDSS) is a large-scale near-IR survey which aim is to cover 7500 square degrees of the Northern sky. The survey is carried out using the Wide Field Camera (WFCAM), with a field of view of 0.21 square degrees, mounted on the 3.8m United Kingdom Infra-red Telescope (UKIRT) in Hawaii. The Large Area Survey (LAS) covers an area of 4000 square degrees in high Galactic latitudes (extragalactic) in the four bands Y(1.0um) J(1.2um) H(1.6um) and K(2.2um) to a depth of K = 18.4. Details of the survey can be found in the in the paper by Lawrence et al. (2007MNRAS.379.1599L) (1 data file).

Structures of M2(SO2)6B12F12 (M = Ag or K) and Ag2(H2O)4B12F12: Comparison of the Coordination of SO2 versus H2O and of B12F122- versus Other Weakly Coordinating Anions to Metal Ions in the Solid State.

PubMed

Malischewski, Moritz; Peryshkov, Dmitry V; Bukovsky, Eric V; Seppelt, Konrad; Strauss, Steven H

2016-12-05

The structures of three solvated monovalent cation salts of the superweak anion B 12 F 12 2- (Y 2- ), K 2 (SO 2 ) 6 Y, Ag 2 (SO 2 ) 6 Y, and Ag 2 (H 2 O) 4 Y, are reported and discussed with respect to previously reported structures of Ag + and K + with other weakly coordinating anions. The structures of K 2 (SO 2 ) 6 Y and Ag 2 (SO 2 ) 6 Y are isomorphous and are based on expanded cubic close-packed arrays of Y 2- anions with M(OSO) 6 + complexes centered in the trigonal holes of one expanded close-packed layer of B 12 centroids (⊙). The K + and Ag + ions have virtually identical bicapped trigonal prism MO 6 F 2 coordination spheres, with M-O distances of 2.735(1)-3.032(2) Å for the potassium salt and 2.526(5)-2.790(5) Å for the silver salt. Each M(OSO) 6 + complex is connected to three other cationic complexes through their six μ-SO 2 -κ 1 O,κ 2 O' ligands. The structure of Ag 2 (H 2 O) 4 Y is unique [different from that of K 2 (H 2 O) 4 Y]. Planes of close-packed arrays of anions are offset from neighboring planes along only one of the linear ⊙···⊙···⊙ directions of the close-packed arrays, with [Ag(μ-H 2 O) 2 Ag(μ-H 2 O) 2 )] ∞ infinite chains between the planes of anions. There are two nearly identical AgO 4 F 2 coordination spheres, with Ag-O distances of 2.371(5)-2.524(5) Å and Ag-F distances of 2.734(4)-2.751(4) Å. This is only the second structurally characterized compound with four H 2 O molecules coordinated to a Ag + ion in the solid state. Comparisons with crystalline H 2 O and SO 2 solvates of other Ag + and K + salts of weakly coordinating anions show that (i) N[(SO 2 ) 2 (1,2-C 6 H 4 )] - , BF 4 - , SbF 6 - , and Al(OC(CF 3 ) 3 ) 4 - coordinate much more strongly to Ag + than does Y 2- , (ii) SnF 6 2- coordinates somewhat more strongly to K + than does Y 2- , and (iii) B 12 Cl 12 2- coordinates to K + about the same as, if not slightly weaker than, Y 2- .

K2: A NEW METHOD FOR THE DETECTION OF GALAXY CLUSTERS BASED ON CANADA-FRANCE-HAWAII TELESCOPE LEGACY SURVEY MULTICOLOR IMAGES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thanjavur, Karun; Willis, Jon; Crampton, David, E-mail: karun@uvic.c

2009-11-20

We have developed a new method, K2, optimized for the detection of galaxy clusters in multicolor images. Based on the Red Sequence approach, K2 detects clusters using simultaneous enhancements in both colors and position. The detection significance is robustly determined through extensive Monte Carlo simulations and through comparison with available cluster catalogs based on two different optical methods, and also on X-ray data. K2 also provides quantitative estimates of the candidate clusters' richness and photometric redshifts. Initially, K2 was applied to the two color (gri) 161 deg{sup 2} images of the Canada-France-Hawaii Telescope Legacy Survey Wide (CFHTLS-W) data. Our simulationsmore » show that the false detection rate for these data, at our selected threshold, is only approx1%, and that the cluster catalogs are approx80% complete up to a redshift of z = 0.6 for Fornax-like and richer clusters and to z approx 0.3 for poorer clusters. Based on the g-, r-, and i-band photometric catalogs of the Terapix T05 release, 35 clusters/deg{sup 2} are detected, with 1-2 Fornax-like or richer clusters every 2 deg{sup 2}. Catalogs containing data for 6144 galaxy clusters have been prepared, of which 239 are rich clusters. These clusters, especially the latter, are being searched for gravitational lenses-one of our chief motivations for cluster detection in CFHTLS. The K2 method can be easily extended to use additional color information and thus improve overall cluster detection to higher redshifts. The complete set of K2 cluster catalogs, along with the supplementary catalogs for the member galaxies, are available on request from the authors.« less

Study of electrical transport properties of (U 1- xY x)RuP 2Si 2

NASA Astrophysics Data System (ADS)

Radha, S.; Park, J.-G.; Roy, S. B.; Coles, B. R.; Nigam, A. K.; McEwen, K. A.

1996-02-01

Electrical resistivity and magnetoresistance ( {δϱ}/{ϱ}) measurements on a series of (U 1- xY x)Ru 2Si 2 (0 ⩽ x ⩽ 0.9) compounds in the temperature range 4.2-300 K and in magnetic fields up to 45 kOe are reported. The resistivity measurements do not show any signature of antiferromagnetism for x > 0.5. The compound URu 2Si 2 exhibits a large, positive ( {δϱ}/{ϱ}) presumably due to destruction of Kondo coherence as well as due to antiferromagnetism. The presence of even 5% Y at U-site weakens the Kondo coherence and reduces the magnetoresistance considerably.

Antisite-disorder, magnetic and thermoelectric properties of Mo-rich Sr2Fe1-yMo1+yO6 (0 ≤y≤ 0.2) double perovskites.

PubMed

Popuri, Srinivasa R; Redpath, Debbie; Chan, Gavin; Smith, Ronald I; Cespedes, Oscar; Bos, Jan-Willem G

2015-06-21

Structure analysis using X-ray and neutron powder diffraction and elemental mapping has been used to demonstrate that nominal A-site deficient Sr(2-x)FeMoO(6-δ) (0 ≤x≤ 0.5) compositions form as Mo-rich Sr(2)Fe(1-y)Mo(1+y)O(6) (0 ≤y≤ 0.2) perovskites at high temperatures and under reducing atmospheres. These materials show a gradual transition from the Fe and Mo rock salt ordered double perovskite structure to a B-site disordered arrangement. Analysis of the fractions of B-O-B' linkages revealed a gradual increase in the number of Mo-O-Mo linkages at the expense of the ferrimagnetic (FIM) Fe-O-Mo linkages that dominate the y = 0 material. All samples contain about 10-15% antiferromagnetic (AF) Fe-O-Fe linkages, independent of the degree of B-site ordering. The magnetic susceptibility of the y = 0.2 sample is characteristic of a small domain ferrimagnet (T(c)∼ 250 K), while room temperature neutron powder diffraction demonstrated the presence of G-type AF ordering linked to the Fe-O-Fe linkages (m(Fe) = 1.25(7)μ(B)). The high temperature thermoelectric properties are characteristic of a metal with a linear temperature dependence of the Seebeck coefficient, S (for all y) and electrical resistivity ρ (y≥ 0.1). The largest thermoelectric power factor S(2)/ρ = 0.12 mW m(-1) K(-1) is observed for Sr(2)FeMoO(6) at 1000 K.

A 2 epoch proper motion catalogue from the UKIDSS Large Area Survey

NASA Astrophysics Data System (ADS)

Smith, Leigh; Lucas, Phil; Burningham, Ben; Jones, Hugh; Pinfield, David; Smart, Ricky; Andrei, Alexandre

2013-04-01

The UKIDSS Large Area Survey (LAS) began in 2005, with the start of the UKIDSS program as a 7 year effort to survey roughly 4000 square degrees at high galactic latitudes in Y, J, H and K bands. The survey also included a significant quantity of 2-epoch J band observations, with epoch baselines ranging from 2 to 7 years. We present a proper motion catalogue for the 1500 square degrees of the 2 epoch LAS data, which includes some 800,000 sources with motions detected above the 5σ level. We developed a bespoke proper motion pipeline which applies a source-unique second order polynomial transformation to UKIDSS array coordinates of each source to counter potential local non-uniformity in the focal plane. Our catalogue agrees well with the proper motion data supplied in the current WFCAM Science Archive (WSA) DR9 catalogue where there is overlap, and in various optical catalogues, but it benefits from some improvements. One improvement is that we provide absolute proper motions, using LAS galaxies for the relative to absolute correction. Also, by using unique, local, 2nd order polynomial tranformations, as opposed to the linear transformations in the WSA, we correct better for any local distortions in the focal plane, not including the radial distortion that is removed by their pipeline.

Assessment of healthcare professionals' knowledge about warfarin-vitamin K drug-nutrient interactions.

PubMed

Couris, R R; Tataronis, G R; Dallal, G E; Blumberg, J B; Dwyer, J T

2000-08-01

Dietary vitamin K can interact with oral anticoagulant drugs and interfere with their therapeutic safety and efficacy. Therefore, knowledge about drug-nutrient interactions involving vitamin K possessed by physicians, pharmacists, dietitians and nurses practicing anticoagulant therapy was assessed. Healthcare practitioners were surveyed using a 30-question, 98-item questionnaire on the most common and/or important food interactions with warfarin, drug interactions with warfarin and general drug-nutrient interactions involving vitamin K. The study sample included 160 randomly selected healthcare providers (40 physicians, pharmacists, dietitians and nurses) from 10 hospitals with 200 to 1000 beds from six Massachusetts regions. Random selection was conducted from a pool of selected healthcare providers practicing anticoagulant therapy who counsel patients receiving warfarin. All surveys were completed within three months of the start of the study, and all participants provided usable data for statistical analysis. The mean scores (+/- SD) on the overall test were 72.5+/-9.0 for pharmacists, 62.51+/-10.6 for physicians, 56.9+/-8.8 for dietitians and 50.2+/-9.3 for nurses, with 100 being a perfect score. Pharmacists scored significantly higher in the area of drug interactions (75.9+/-11.3, p<0.05). Dietitians scored higher in the area of food interactions (73.0+/-10.3). No significant differences between physicians and pharmacists were evident on general drug-nutrient interactions. While over 87% of the healthcare professionals correctly identified some common foods containing large amounts of vitamin K, such as broccoli and spinach, fewer than 25% were able to identify others such as pea soup, coleslaw and dill pickles. Although the healthcare professionals surveyed in this study appear to have demonstrated some proficiency in their respective areas of expertise, they exhibited less knowledge in others. Therefore, additional training and integration of knowledge and

Wetland survey of selected areas in the K-24 Site Area of responsibility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rosensteel, B.A.; Awl, D.J.

1995-07-01

In accordance with DOE Regulations for Compliance with Floodplain/Wetlands Environmental Review Requirements, wetland surveys were conducted in selected areas within the K-25 Area of Responsibility during the summer of 1994. These areas are Mitchell Branch, Poplar Creek, the K-770 OU, Duct Island Peninsula, the Powerhouse area, and the K-25 South Corner. Previously surveyed areas included in this report are the main plant area of the K-25 Site, the K-901 OU, the AVLIS site, and the K-25 South Site. Wetland determinations were based on the USACE methodology. Forty-four separate wetland areas, ranging in size from 0.13 to 4.23 ha, were identified.more » Wetlands were identified in all of the areas surveyed with the exception of the interior of the Duct Island Peninsula and the main plant area of the K-25 Site. Wetlands perform functions such as floodflow alteration, sediment stabilization, sediment and toxicant retention, nutrient transformation, production export, and support of aquatic species and wildlife diversity and abundance. The forested, scrub-shrub, and emergent wetlands identified in the K-25 area perform some or all of these functions to varying degrees.« less

Functionalized Congeners of P2Y1 Receptor Antagonists:

DOE Office of Scientific and Technical Information (OSTI.GOV)

de Castro, Sonia; Maruoka, Hiroshi; Hong, Kunlun

2010-01-01

The P2Y{sub 1} receptor is a prothrombotic G protein-coupled receptor (GPCR) activated by ADP. Preference for the North (N) ring conformation of the ribose moiety of adenine nucleotide 3',5'-bisphosphate antagonists of the P2Y{sub 1} receptor was established by using a ring-constrained methanocarba (a bicyclo[3.1.0]hexane) ring as a ribose substitute. A series of covalently linkable N{sup 6}-methyl-(N)-methanocarba-2'-deoxyadenosine-3',5'-bisphosphates containing extended 2-alkynyl chains was designed, and binding affinity at the human (h) P2Y{sub 1} receptor determined. The chain of these functionalized congeners contained hydrophilic moieties, a reactive substituent, or biotin, linked via an amide. Variation of the chain length and position of anmore » intermediate amide group revealed high affinity of carboxylic congener 8 (K{sub i} 23 nM) and extended amine congener 15 (K{sub i} 132 nM), both having a 2-(1-pentynoyl) group. A biotin conjugate 18 containing an extended {epsilon}-aminocaproyl spacer chain exhibited higher affinity than a shorter biotinylated analogue. Alternatively, click coupling of terminal alkynes of homologous 2-dialkynyl nucleotide derivatives to alkyl azido groups produced triazole derivatives that bound to the P2Y{sub 1} receptor following deprotection of the bisphosphate groups. The preservation of receptor affinity of the functionalized congeners was consistent with new P2Y{sub 1} receptor modeling and ligand docking. Attempted P2Y{sub 1} antagonist conjugation to PAMAM dendrimer carriers by amide formation or palladium-catalyzed reaction between an alkyne on the dendrimer and a 2-iodopurine-derivatized nucleotide was unsuccessful. A dialkynyl intermediate containing the chain length favored in receptor binding was conjugated to an azide-derivatized dendrimer, and the conjugate inhibited ADP-promoted human platelet aggregation. This is the first example of attaching a strategically functionalized P2Y receptor antagonist to a PAMAM

Oxygen ionic conductivity of NTE materials of cubic Zr 1- xLn xW 2- yMo yO 8- x/2 (Ln = Er, Yb)

NASA Astrophysics Data System (ADS)

Li, Hai-Hua; Xia, Hai-Ting; Jing, Xi-Ping; Zhao, Xin-Hua

2008-08-01

Cubic Zr 1- xLn xW 2- yMo yO 8- x/2 (Ln = Er: x = 0.01, 0.02, 0.03; y = 0; Ln = Yb: x = 0.02, 0.03; y = 0.4) solid solutions, well-known negative thermal expansion (NTE) materials were prepared by using conventional solid state reactions. The morphology and the composition of the fracture surfaces of the ceramic pellets were determined by SEM and EDX technology. The conductance properties of the pellets, such as conductivity and conductance activation energy, were studied by AC impedance spectroscopy and the materials perform clearly oxygen ionic conduction with the conductivity of about 10 -4 S cm -1 at 673 K, a comparable value to that of ceria based solid electrolytes. The substitution of Mo for W enhanced the thermal stability of ZrW 2O 8, so that the conductivity of Zr 0.98Yb 0.02W 1.6Mo 0.4O 7.99 ceramic can be measured up to 873 K, which is about 5.9 × 10 -4 S cm -1.

Calcium-activated K(+) channel (K(Ca)3.1) activity during Ca(2+) store depletion and store-operated Ca(2+) entry in human macrophages.

PubMed

Gao, Ya-dong; Hanley, Peter J; Rinné, Susanne; Zuzarte, Marylou; Daut, Jurgen

2010-07-01

STIM1 'senses' decreases in endoplasmic reticular (ER) luminal Ca(2+) and induces store-operated Ca(2+) (SOC) entry through plasma membrane Orai channels. The Ca(2+)/calmodulin-activated K(+) channel K(Ca)3.1 (previously known as SK4) has been implicated as an 'amplifier' of the Ca(2+)-release activated Ca(2+) (CRAC) current, especially in T lymphocytes. We have previously shown that human macrophages express K(Ca)3.1, and here we used the whole-cell patch-clamp technique to investigate the activity of these channels during Ca(2+) store depletion and store-operated Ca(2+) influx. Using RT-PCR, we found that macrophages express the elementary CRAC channel components Orai1 and STIM1, as well as Orai2, Orai3 and STIM2, but not the putatively STIM1-activated channels TRPC1, TRPC3-7 or TRPV6. In whole-cell configuration, a robust Ca(2+)-induced outwardly rectifying K(+) current inhibited by clotrimazole and augmented by DC-EBIO could be detected, consistent with K(Ca)3.1 channel current (also known as intermediate-conductance IK1). Introduction of extracellular Ca(2+) following Ca(2+) store depletion via P2Y(2) receptors induced a robust charybdotoxin (CTX)- and 2-APB-sensitive outward K(+) current and hyperpolarization. We also found that SOC entry induced by thapsigargin treatment induced CTX-sensitive K(+) current in HEK293 cells transiently expressing K(Ca)3.1. Our data suggest that SOC and K(Ca)3.1 channels are tightly coupled, such that a small Ca(2+) influx current induces a much large K(Ca)3.1 channel current and hyperpolarization, providing the necessary electrochemical driving force for prolonged Ca(2+) signaling and store repletion. Copyright 2010 Elsevier Ltd. All rights reserved.

Phase Diagram of K x Fe 2 - y Se 2 - z S z and the Suppression of its Superconducting State by an Fe 2 - Se / S Tetrahedron Distortion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lei, Hechang; Abeykoon, Milinda; Bozin, Emil S.

2011-09-01

We report structurally tuned superconductivity in a K x Fe 2 - y Se 2 - z S z ( 0 ≤ z ≤ 2 ) phase diagram. Superconducting T c is suppressed as S is incorporated into the lattice, eventually vanishing at 80% of S. The magnetic and conductivity properties can be related to stoichiometry on a poorly occupied Fe1 site and the local environment of a nearly fully occupied Fe2 site. The decreasing T c coincides with the increasing Fe1 occupancy and the overall increase in Fe stoichiometry from z = 0 to z = 2 . Ourmore » results indicate that the irregularity of the Fe 2 - Se / S tetrahedron is an important controlling parameter that can be used to tune the ground state in the new superconductor family.« less

Comets C/2003 X5-X11 and Y2-Y10 (SOHO)

NASA Astrophysics Data System (ADS)

Battams, K.; Boschat, M.; Zhou, X.-M.; Hoffman, T.; Leprette, X.; Matson, R.; Kracht, R.; Sachs, J.; Marsden, B. G.; Kisala, R.

2004-06-01

Further to IAUC 8356, K. Battams reports measurements for additional Kreutz sungrazing comets found on SOHO website C2 images by M. Boschat (C/2003 X5, X7, Y5, Y8), X.-m. Zhou (C/2003 X6, X9, X11), T. Hoffman (C/2003 X8), X. Leprette (C/2003 X10, Y2), R. Matson (2003 Y3, Y9, Y10), R. Kracht (C/2003 Y4, Y7), and J. Sachs (C/2003 Y6). C/2003 Y6 and Y7 were also visible on C3 images. The reductions by B. G. Marsden (and by R. Kisala for C/2003 Y8, Y9, Y10) and orbital elements by Marsden appear on the MPECs cited below. Comet 2003 UT R.A. (2000) Decl. MPEC C/2003 X5 Dec. 4.896 16 46.9 -24 12 2004-L24 C/2003 X6 6.396 16 52.2 -24 20 2004-L24 C/2003 X7 7.829 16 58.6 -24 27 2004-L24 C/2003 X8 8.246 17 00.9 -24 31 2004-L24 C/2003 X9 8.621 17 02.2 -24 34 2004-L24 C/2003 X10 11.188 17 14.5 -24 41 2004-L25 C/2003 X11 13.588 17 25.7 -24 57 2004-L25 C/2003 Y2 19.621 17 53.6 -25 08 2004-L25 C/2003 Y3 19.979 17 55.0 -25 02 2004-L25 C/2003 Y4 20.729 17 58.8 -25 14 2004-L25 C/2003 Y5 22.771 18 08.5 -25 08 2004-L25 C/2003 Y6 23.571 18 14.3 -27 22 2004-L26 C/2003 Y7 24.638 18 20.0 -27 44 2004-L26 C/2003 Y8 25.288 18 19.6 -25 00 2004-L67 C/2003 Y9 25.479 18 20.7 -24 46 2004-L67 C/2003 Y10 26.064 18 23.5 -24 50 2004-L67

Nucleoli in human early erythroblasts (K2, K1, K1/2 cells).

PubMed

Smetana, K; Jirásková, I; Klamová, H

2005-01-01

Human early erythroid precursors classified according to the nuclear size were studied to provide information on nucleoli in these cells using simple cytochemical procedures for demonstration of RNA and proteins of silver-stained nucleolar organizers. K2 cells with nuclear diameter larger than 13 microm and K1 cells with nuclear diameter larger than 9 microm corresponding to proerythroblasts and macroblasts (large basophilic erythroblasts) mostly possessed large irregularly shaped nucleoli with multiple fibrillar centres representing "active nucleoli". K1/2 cells with nuclear diameter smaller than 9 microm corresponding to small basophilic erythroblasts were usually characterized by the presence of micronucleoli representing "inactive nucleolar types". On the other hand, a few K1/2 cells contained large nucleoli with multiple fibrillar centres similar to those present in K2 cells and thus appeared as "microproerythroblasts". The nucleolar asynchrony expressed by the presence of large irregularly shaped nucleoli with multiple nucleoli (active nucleoli) and ring-shaped nucleoli (resting nucleoli) in one and the same nucleus of K2 or K1 cells was not exceptional and might reflect a larger resistance of these cells to negative factors influencing the erythropoiesis. The intranucleolar translocation of silver-stained nucleolus organized regions was noted in K2 cells and might indicate the premature aging of these cells without further differentiation. More studies, however, are required in this direction.

TL and OSL properties of beta irradiated Y2O3 nanocrystal

NASA Astrophysics Data System (ADS)

Shivaramu, N. J.; Lakshminarasappa, B. N.; Nagabhushana, K. R.; Tatumi, S. H.; Rocca, R. R.; Singh, Fouran

2017-05-01

Nanocrystalline yttrium oxide (Y2O3) is synthesized by low temperature sol-gel technique and synthesized material is annealed at 900°C. The annealed β-rayed Y2O3 two TL glows with prominent peak at 407 K and weak glow peak at 643 K were observed in all irradiated samples. It is found that TL glow peaks intensity linearly increases with increase in β-dose from 0.813 - 40.625 Gy. The TL kinetic parameters are calculated using glow curve deconvoluted (GCD) method. The TL glows exhibits general order kinetics. Intense optical stimulated luminescence (OSL) is observed in the Y2O3 sample. These material exhibits linearity and reproducibility and hence, it suggests that this material may be used as dosimetric applications.

Successive magnetic transitions of the pseudo-ternary compounds Ho1-xRxRh2Si2 (R=Y, La)

NASA Astrophysics Data System (ADS)

Shigeoka, Toru; Uchima, Kiyoharu; Uwatoko, Yoshiya

2018-05-01

Magnetic measurements on the pseudo-ternary compounds Ho1-xRxRh2Si2 (R = Y or La = Y or La) were performed in order to get information on the origin of "the successive component-separated magnetic transitions" which appear in HoRh2Si2. The lattice parameters a and c remain almost constant during changes to Y composition x, while they increase with increasing La composition x. The c/a ratios are also constant in the Y-system, and they increase with increasing x in the La-system especially for above around x = 0.4. The transition temperatures, TN1 = 29.1 K, Tt = 27.3 K and TN2 =12.1 K at x = 0, decrease with increasing x. The rates of decrease for TN1 and TN2 in the Y-system accord with those in the La system below x = 0.4. The critical compositions for TN1 and TN2 are determined to be xN1 = 0.88 and xN2 = 0.59 in the La-system, respectively, and xN1 = 0.98 and xN2 = 0.75 in the Y-system. In both the systems, "the successive component-separated magnetic transitions" appear for the wide x regions. The magnetic ordered state persists in very dilute Ho-compounds in spite of much weak magnetic interactions. The effective magnetic moments are almost constant for the ordered compounds; μeff = 10.6 ± 0.30 μB/Ho. These behaviors are strange, indicating a strong correlation exists in these systems.

Colorado K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper No. 26

ERIC Educational Resources Information Center

DiPerna, Paul

2015-01-01

The purpose of the "Colorado K-12 & School Choice Survey" is to measure public opinion on, and in some cases awareness or knowledge of, a range of K-12 education topics and school choice reforms. A total of 601 telephone interviews were completed from August 29 to September 16, 2015, with questions on the direction of K-12 education,…

Identification of young stellar variables with KELT for K2 - II. The Upper Scorpius association

NASA Astrophysics Data System (ADS)

Ansdell, Megan; Oelkers, Ryan J.; Rodriguez, Joseph E.; Gaidos, Eric; Somers, Garrett; Mamajek, Eric; Cargile, Phillip A.; Stassun, Keivan G.; Pepper, Joshua; Stevens, Daniel J.; Beatty, Thomas G.; Siverd, Robert J.; Lund, Michael B.; Kuhn, Rudolf B.; James, David; Gaudi, B. Scott

2018-01-01

High-precision photometry from space-based missions such as K2 and Transiting Exoplanet Survey Satellite enables detailed studies of young star variability. However, because space-based observing campaigns are often short (e.g. 80 d for K2), complementary long-baseline photometric surveys are critical for obtaining a complete understanding of young star variability, which can change on time-scales of minutes to years. We therefore present and analyse light curves of members of the Upper Scorpius association made over 5.5 yr by the ground-based Kilodegree Extremely Little Telescope (KELT), which complement the high-precision observations of this region taken by K2 during its Campaigns 2 and 15. We show that KELT data accurately identify the periodic signals found with high-precision K2 photometry, demonstrating the power of ground-based surveys in deriving stellar rotation periods of young stars. We also use KELT data to identify sources exhibiting variability that is likely related to circumstellar material and/or stellar activity cycles; these signatures are often unseen in the short-term K2 data, illustrating the importance of long-term monitoring surveys for studying the full range of young star variability. We provide the KELT light curves as electronic tables in an ongoing effort to establish legacy time series data sets for young stellar clusters.

Preparation of minor ginsenosides C-Mc, C-Y, F2, and C-K from American ginseng PPD-ginsenoside using special ginsenosidase type-I from Aspergillus niger g.848.

PubMed

Liu, Chun-Ying; Zhou, Rui-Xin; Sun, Chang-Kai; Jin, Ying-Hua; Yu, Hong-Shan; Zhang, Tian-Yang; Xu, Long-Quan; Jin, Feng-Xie

2015-07-01

Minor ginsenosides, those having low content in ginseng, have higher pharmacological activities. To obtain minor ginsenosides, the biotransformation of American ginseng protopanaxadiol (PPD)-ginsenoside was studied using special ginsenosidase type-I from Aspergillus niger g.848. DEAE (diethylaminoethyl)-cellulose and polyacrylamide gel electrophoresis were used in enzyme purification, thin-layer chromatography and high performance liquid chromatography (HPLC) were used in enzyme hydrolysis and kinetics; crude enzyme was used in minor ginsenoside preparation from PPD-ginsenoside; the products were separated with silica-gel-column, and recognized by HPLC and NMR (Nuclear Magnetic Resonance). The enzyme molecular weight was 75 kDa; the enzyme firstly hydrolyzed the C-20 position 20-O-β-D-Glc of ginsenoside Rb1, then the C-3 position 3-O-β-D-Glc with the pathway Rb1→Rd→F2→C-K. However, the enzyme firstly hydrolyzed C-3 position 3-O-β-D-Glc of ginsenoside Rb2 and Rc, finally hydrolyzed 20-O-L-Ara with the pathway Rb2→C-O→C-Y→C-K, and Rc→C-Mc1→C-Mc→C-K. According to enzyme kinetics, K m and V max of Michaelis-Menten equation, the enzyme reaction velocities on ginsenosides were Rb1 > Rb2 > Rc > Rd. However, the pure enzyme yield was only 3.1%, so crude enzyme was used for minor ginsenoside preparation. When the crude enzyme was reacted in 3% American ginseng PPD-ginsenoside (containing Rb1, Rb2, Rc, and Rd) at 45°C and pH 5.0 for 18 h, the main products were minor ginsenosides C-Mc, C-Y, F2, and C-K; average molar yields were 43.7% for C-Mc from Rc, 42.4% for C-Y from Rb2, and 69.5% for F2 and C-K from Rb1 and Rd. Four monomer minor ginsenosides were successfully produced (at low-cost) from the PPD-ginsenosides using crude enzyme.

An investigation into the numerical prediction of boundary layer transition using the K.Y. Chien turbulence model

NASA Technical Reports Server (NTRS)

Stephens, Craig A.; Crawford, Michael E.

1990-01-01

Assessments were made of the simulation capabilities of transition models developed at the University of Minnesota, as applied to the Launder-Sharma and Lam-Bremhorst two-equation turbulence models, and at The University of Texas at Austin, as applied to the K. Y. Chien two-equation turbulence model. A major shortcoming in the use of the basic K. Y. Chien turbulence model for low-Reynolds number flows was identified. The problem with the Chien model involved premature start of natural transition and a damped response as the simulation moved to fully turbulent flow at the end of transition. This is in contrast to the other two-equation turbulence models at comparable freestream turbulence conditions. The damping of the transition response of the Chien turbulence model leads to an inaccurate estimate of the start and end of transition for freestream turbulence levels greater than 1.0 percent and to difficulty in calculating proper model constants for the transition model.

Assessment of vitamin K2 levels in osteoporotic patients: a case control study.

PubMed

Noori, Akram; Lashkari, Mahin; Oveisi, Sonia; Khair Khah, Mohamad Reza; Zargar, Ali

2014-07-14

The aim of this study was to measure the level of Vitamin K2 (Vit K2) in osteoporotic patients and individuals with normal bone density as controls. This case-control study was done in Outpatient Department of Rheumatology at Qazvin Boo-ali Sina Hospital in 2013. Participants were 50 patients with osteoporotic densitometry measured by DEXA (T score? -2.5) who were matched with 48 persons in control group with normal bone density (T score> -1). The level of Vit K2 in samples was measured using enzyme linked immunosorbent assay (ELISA). Data were analyzed by Mann-Whitney U test and Chi-square test. The level of Vit K2 in patients with osteoporosis was not significantly different from the control group (Median: 75.95 vs. 71.35 nmol/L, respectively; P-value: 0.709). The authors determined cut-offs 75 percentile of vitamin K2 in all participants that was 85 nmol/L and percentages of persons in two groups were similar. Although Vit K2 level in patients with osteoporosis was not significantly different from the control group, further studies are necessary to confirm the association of osteoporosis and Vit K2.

Electronic structure of Pr{sub 1{minus}x}Y{sub x}Ba{sub 2}Cu{sub 3}O{sub y} (x=0, 0.5, and 1.0)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kakinuma, K.; Fueki, K.

1997-08-01

In order to elucidate the reason why PrBa{sub 2}Cu{sub 3}O{sub y}is not a superconductor, we examined the Pr valence and measured the oxygen nonstoichiometry and the conductivity at temperatures up to 1200 K for three kinds of oxides, PrBa{sub 2}Cu{sub 3}O{sub y}, (Pr{sub 0.5}Y{sub 0.5})Ba{sub 2}Cu{sub 3}O{sub y}, and YBa{sub 2}Cu{sub 3}O{sub y}. The valence of Pr was found to be +3. Any difference was not found in oxygen nonstoichiometry and conductivity among three kinds of oxides. We analyzed the data of oxygen nonstoichiometry on the basis of defect thermodynamics and calculated the numbers of Cu{sup +}, Cu{sup 2+}, andmore » Cu{sup 3+} ions in the unit cell as a function of y. The number of Cu{sup 3+} ions (the amount of holes) was found to be proportional to ({Delta}y){sup 1.6}({Delta}y=y{minus}6.0), whereas the conductivity was found to be proportional to ({Delta}y){sup 3.2} in these oxides. We interpreted the remarkable increase of {sigma} with {Delta}y as an evidence of the increase of both mobility and hole concentration with {Delta}y. At high temperatures, we detected the conductivity minimum {sigma}{sub min} which was found in the log{sub 10}{sigma}{minus}log{sub 10}P{sub O{sub 2}} plot at constant temperatures. From the slope of the Arrhenius plot for {sigma}{sub min}, the band gap was determined to be 1.21, 1.32, and 1.37 eV for PrBa{sub 2}Cu{sub 3}O{sub y}, (Pr{sub 0.5}Y{sub 0.5})Ba{sub 2}Cu{sub 3}O{sub y} and YBa{sub 2}Cu{sub 3}O{sub y}, respectively. We determined the conductivity of the same oxygen content as a function of temperature from 4.2 to 1200 K. The energy gap {Delta}E between the acceptor level and the top of the valence band was calculated from the slope of the Arrhenius plot for conductivity. {Delta}E for superconducting YBa{sub 2}Cu{sub 3}O{sub y} and (Pr{sub 0.5}Y{sub 0.5})Ba{sub 2}Cu{sub 3}O{sub y} were zero at 300 K but that for nonsuperconducting PrBa{sub 2}Cu{sub 3}O{sub y} was 20 meV at 100 K even for y=6.93. (Abstract

Integrated Geophysical Survey on Deák Ferenc Sluice in Hungary

NASA Astrophysics Data System (ADS)

Kanli, A. I.

2015-12-01

ALI ISMET KANLI1*, G. TALLER2, Z. PRONAY2, P. TILDY2, P. NAGY3, E. TOROS2 *1Istanbul University, Turkey, kanli@istanbul.edu.tr, 2Geological and Geophysical Institute of Hungary,3MinGeo, Hungary The Ferenc Channel is one of the main irrigation and ship channel in south of Hungary, existing from 1801. The water level is controlled by the Deák Ferenc Sluice in the channel which was constructed in 1875. At that time, the sluice was unique in Europe with its two channels and brick-walls. The west channel was used for controlling the amount of water and the east channel was used for shipping. In the study, before starting to the restoration and reinforcement plannings at the sluice, non-destructive geophysical investigations were executed. In the first stage, ultra-high frequency seismic (80 kHz) and acoustic (5 kHz) investigations of the floor slab were carried out from a boat on the water level. Due to the water level was approximately 2 m, we could use the advantage of the water ensuring very good coupling with seismic sensors for high frequency seismic and acoustic measurements. In the second stage, resistivity measurements were carried out in the eastern part of the sluice which was used as the shipping channel. Three profiles were measured to map the resistivity distribution of the slab. In the third stage, for better understanding the stability conditions of the walls and easy to compare with the data of GPR measurements, the wall of the sluice were investigated by a simple seismic direct wave method using seismic P-waves for mapping seismic velocities. The last stage of the survey was the GPR measurements that were carried out both on the walls and on the slab of the sluice. During the investigation, the channels were empty and without water. The integrated survey and the interpretation of the results showed us that there were some faults, cracks and voids in the slab existed in the whole grossness of the slab and the brick walls were builded from inhomogenous

K-KIDS: Companioins to K Dwarfs Within 50 Parsecs

NASA Astrophysics Data System (ADS)

Nusdeo, Daniel Anthony; Winters, Jennifer; Paredes-Alvarez, Leonardo; Horch, Elliott; Jao, Wei-Chun; Henry, Todd J.; RECONS Institute

2017-01-01

How many K dwarfs have “kids?” Stellar multiplicity fractions have been obtained for most spectral types, most recently by Raghavan et al. (2010) and Winters et al. (2015), finding rates of 50% for solar-type stars and 27% for M dwarfs, respectively. These findings will be crucial to improving our understanding of solar-system formation, but there has not yet been a statistically significant survey for K dwarfs to bridge the gap between G and M stars. To create a sample for a robust multiplicity survey, an initial set of 1048 K dwarfs was built using the Hipparcos and 2MASS catalogs, the companions of which are called “K-KIDS.” Future releases from Gaia will help us to expand K-KIDS into a volume-complete sample out to 50-pc, and we project that the final sample will contain over 3000 stars, making this the largest volume-complete multiplicity survey ever undertaken. For observational purposes, the targeted K dwarfs are confined equatorially to -30 < DEC < +30 to ensure all stars are observable from either hemisphere. The survey for K-KIDS is split into three companion-separation regimes: small (0.02 - 2.00 arcseconds), medium (2.00 - 10.00 arcseconds), and distant (10.00+ arcseconds). Small separation companions are resolved using the Differential Speckle Survey Instrument, with which we have observed 964 out of 1048 systems to date, already finding 135 new K-KIDS. Medium separation companions are observed via a series of three observations per star at the CTIO 0.9-m telescope, integrating for 3, 30, and 300 seconds to reveal companions of various brightnesses. Finally, a common proper-motion search is used to find companions at distant separations via blinking of digitialized images in the SuperCOSMOS archive, in addition to a large-scale literature survey for previously-discovered multiples. The small and distant surveys are nearing completion, and continued progress on the medium survey ensures that a statistically significant multiplicity rate for K

Hole doping and pressure effects on the II-II-V-based diluted magnetic semiconductor ( B a 1 - x K x ) ( Z n 1 - y M n y ) 2 A s 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, F.; Zhao, G. Q.; Escanhoela, Jr., C. A.

We investigate doping- and pressure-induced changes in the electronic state of Mn 3d and As 4p orbitals in II-II-V based diluted magnetic semiconductor (Ba 1-x,K x)(Zn 1-y,Mn y) 2As 2 to shed light into the mechanism of indirect exchange interactions leading to high ferromagnetic ordering temperature (T c = 230 K in optimally doped samples). A suite of x-ray spectroscopy experiments (emission, absorption and dichroism) show that the emergence, and further enhancement of ferromagnetic interactions with increased hole doping into the As 4p band is accompanied by a decrease in local 3d spin density at Mn sites. This is amore » result of increasing Mn 3d - As 4p hybridization with hole doping which enhances indirect exchange interactions between Mn dopants and gives rise to induced magnetic polarization in As 4p states. On the contrary, application of pressure suppresses exchange interactions. While Mn Kβ emission spectra show a weak response of 3d state to pressure, clear As 4p band broadening (hole delocalization) is observed under pressure ultimately leading to loss of ferromagnetism concomitant with a semiconductor to metal transition. The pressure response of As 4p and Mn 3d states is intimately connected with the evolution of the As-As interlayer distance and the geometry of the MnAs 4 tetrahedral units, which we probed with X-ray diffraction. Our results indicate that hole doping increases the degree of covalency between the anion (As) p states and cation (Mn) d states in the MnA s4 tetrahedron, a crucial ingredient to promote indirect exchange interactions between Mn dopants and high T c ferromagnetism. As a result, the instability of ferromagnetism and semiconducting state against pressure is mainly dictated by delocalization of anion p states.« less

Hole doping and pressure effects on the II-II-V-based diluted magnetic semiconductor ( B a 1 - x K x ) ( Z n 1 - y M n y ) 2 A s 2

DOE PAGES

Sun, F.; Zhao, G. Q.; Escanhoela, Jr., C. A.; ...

2017-03-13

We investigate doping- and pressure-induced changes in the electronic state of Mn 3d and As 4p orbitals in II-II-V based diluted magnetic semiconductor (Ba 1-x,K x)(Zn 1-y,Mn y) 2As 2 to shed light into the mechanism of indirect exchange interactions leading to high ferromagnetic ordering temperature (T c = 230 K in optimally doped samples). A suite of x-ray spectroscopy experiments (emission, absorption and dichroism) show that the emergence, and further enhancement of ferromagnetic interactions with increased hole doping into the As 4p band is accompanied by a decrease in local 3d spin density at Mn sites. This is amore » result of increasing Mn 3d - As 4p hybridization with hole doping which enhances indirect exchange interactions between Mn dopants and gives rise to induced magnetic polarization in As 4p states. On the contrary, application of pressure suppresses exchange interactions. While Mn Kβ emission spectra show a weak response of 3d state to pressure, clear As 4p band broadening (hole delocalization) is observed under pressure ultimately leading to loss of ferromagnetism concomitant with a semiconductor to metal transition. The pressure response of As 4p and Mn 3d states is intimately connected with the evolution of the As-As interlayer distance and the geometry of the MnAs 4 tetrahedral units, which we probed with X-ray diffraction. Our results indicate that hole doping increases the degree of covalency between the anion (As) p states and cation (Mn) d states in the MnA s4 tetrahedron, a crucial ingredient to promote indirect exchange interactions between Mn dopants and high T c ferromagnetism. As a result, the instability of ferromagnetism and semiconducting state against pressure is mainly dictated by delocalization of anion p states.« less

Superconducting transition temperature in the Y(1-x)M(x)Ba2Cu3O(y) system

NASA Astrophysics Data System (ADS)

Suzuki, Takeyuki; Yamazaki, Tsutomu; Sekine, Ryuuta; Koukitsu, Akinori; Seki, Hisashi

1989-04-01

Experimental results are presented for the inclusion of compositional additives, M, to the sintered high-temperature superconductor Y(1-x)M(x)Ba2Cu3O(y); M can be the oxides of Mg, Ce, Gd, Yb, Ti, Zr, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Zn, B, Al, Ga, In, Si, Ge, Sn, Pb, Sb, Bi, and Te, as well as Li, Na, K, Ca, Sr, and La carbonates. Temperature dependence of the electrical resistance was measured down to about 80 K. Attention is given to the influence of ionic radius and the valence of the M species.

Idaho K-12 & School Choice Survey: What Do Voters Say about K-12 Education. Polling Paper No. 5

ERIC Educational Resources Information Center

DiPerna, Paul

2012-01-01

The "Idaho K-12 & School Choice Survey" project, commissioned by The Friedman Foundation for Educational Choice and conducted by Braun Research Incorporated (BRI), measures Idaho registered voters' familiarity and views on a range of K-12 education issues and school choice reforms. We report response "levels" and…

Nonstoichiometry in inorganic fluorides: 2. Ionic conductivity of nonstoichiometric M 1 - x R xF2 + x and R 1 - y M yF3 - y crystals ( M = Ca, Sr, Ba; R are rare earth elements)

NASA Astrophysics Data System (ADS)

Sobolev, B. P.; Sorokin, N. I.

2014-11-01

The peak manifestation of nonstoichiometry in fluoride systems in the number of phases with valuable properties and wide homogeneity ranges is 45 MF2- RF3 systems, where M = Ca, Sr, Ba and R are 15 rare earth elements from La to Lu and Y (with Pm and Sc excluded). A deviation from stoichiometry in crystals of the M 1 - x R xF2 + x (CaF2 fluorite type) and R 1 - y M yF3 - y (LaF3 tysonite type) phases is responsible for the fluorine superionic conductivity σ. The range of variation in σ with changes in the qualitative ( M, R) and quantitative ( x, y) compositions in both structure types is very wide. The σ value changes by a factor of 108 in the M 1 - x R xF2 + x phases (at 500 K) and by a factor of 106 in the R 1 - y M yF3 - y phases (at 293 K). Changing compositions, one can also obtain crystals with σ values large enough for their use as fluorine-conducting solid electrolytes. Phases promising for solid electrolytes were revealed in the MFm- RFn systems ( m < n ≤ 4), which were studied within the program of searching for new multicomponent fluoride materials at the Institute of Crystallography, Russian Academy of Sciences (IC RAS). Superionic conductivity is one of the peak manifestations of the influence of defect structure of nonstoichiometric crystals on their properties. The subject of this review is the results of the studies performed at the IC RAS on the ionic conductivity of single crystals of the M 1 - x R xF2 + x and R 1 - y M yF3 - y nonstoichiometric phases.

Chemical and Electrochemical Asymmetric Dihydroxylation of Olefins in I(2)-K(2)CO(3)-K(2)OsO(2)(OH)(4) and I(2)-K(3)PO(4)/K(2)HPO(4)-K(2)OsO(2)(OH)(4) Systems with Sharpless' Ligand.

PubMed

Torii, Sigeru; Liu, Ping; Bhuvaneswari, Narayanaswamy; Amatore, Christian; Jutand, Anny

1996-05-03

Iodine-assisted chemical and electrochemical asymmetric dihydroxylation of various olefins in I(2)-K(2)CO(3)-K(2)OsO(2)(OH)(4) and I(2)-K(3)PO(4)/K(2)HPO(4)-K(2)OsO(2)(OH)(4) systems with Sharpless' ligand provided the optically active glycols in excellent isolated yields and high enantiomeric excesses. Iodine (I(2)) was used stoichiometrically for the chemical dihydroxylation, and good results were obtained with nonconjugated olefins in contrast to the case of potassium ferricyanide as a co-oxidant. The potentiality of I(2) as a co-oxidant under stoichiometric conditions has been proven to be effective as an oxidizing mediator in electrolysis systems. Iodine-assisted asymmetric electro-dihydroxylation of olefins in either a t-BuOH/H(2)O(1/1)-K(2)CO(3)/(DHQD)(2)PHAL-(Pt) or t-BuOH/H(2)O(1/1)-K(3)PO(4)/K(2)HPO(4)/(DHQD)(2)PHAL-(Pt) system in the presence of potassium osmate in an undivided cell was investigated in detail. Irrespective of the substitution pattern, all the olefins afforded the diols in high yields and excellent enantiomeric excesses. A plausible mechanism is discussed on the basis of cyclic voltammograms as well as experimental observations.

Feasibility of 4D flow MR imaging of the brain with either Cartesian y-z radial sampling or k-t SENSE: comparison with 4D Flow MR imaging using SENSE.

PubMed

Sekine, Tetsuro; Amano, Yasuo; Takagi, Ryo; Matsumura, Yoshio; Murai, Yasuo; Kumita, Shinichiro

2014-01-01

A drawback of time-resolved 3-dimensional phase contrast magnetic resonance (4D Flow MR) imaging is its lengthy scan time for clinical application in the brain. We assessed the feasibility for flow measurement and visualization of 4D Flow MR imaging using Cartesian y-z radial sampling and that using k-t sensitivity encoding (k-t SENSE) by comparison with the standard scan using SENSE. Sixteen volunteers underwent 3 types of 4D Flow MR imaging of the brain using a 3.0-tesla scanner. As the standard scan, 4D Flow MR imaging with SENSE was performed first and then followed by 2 types of acceleration scan-with Cartesian y-z radial sampling and with k-t SENSE. We measured peak systolic velocity (PSV) and blood flow volume (BFV) in 9 arteries, and the percentage of particles arriving from the emitter plane at the target plane in 3 arteries, visually graded image quality in 9 arteries, and compared these quantitative and visual data between the standard scan and each acceleration scan. 4D Flow MR imaging examinations were completed in all but one volunteer, who did not undergo the last examination because of headache. Each acceleration scan reduced scan time by 50% compared with the standard scan. The k-t SENSE imaging underestimated PSV and BFV (P < 0.05). There were significant correlations for PSV and BFV between the standard scan and each acceleration scan (P < 0.01). The percentage of particles reaching the target plane did not differ between the standard scan and each acceleration scan. For visual assessment, y-z radial sampling deteriorated the image quality of the 3 arteries. Cartesian y-z radial sampling is feasible for measuring flow, and k-t SENSE offers sufficient flow visualization; both allow acquisition of 4D Flow MR imaging with shorter scan time.

Minnesota K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper No. 23

ERIC Educational Resources Information Center

DiPerna, Paul

2015-01-01

The "Minnesota K-12 & School Choice Survey" project, commissioned by the Friedman Foundation for Educational Choice and conducted by Braun Research, Inc. (BRI), measures Minnesota registered voters' familiarity and views on a range of K-12 education topics and school choice reforms. The author and his colleagues report response…

Washington K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper Number 6

ERIC Educational Resources Information Center

DiPerna, Paul

2012-01-01

The "Washington K-12 & School Choice Survey" project, commissioned by the Friedman Foundation for Educational Choice and conducted by Braun Research Incorporated (BRI), measures Washington registered voters' familiarity and views on a range of K-12 education topics and school choice reforms. The author and his colleagues report…

Alaska K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper No. 3

ERIC Educational Resources Information Center

DiPerna, Paul

2011-01-01

The "Alaska K-12 & School Choice Survey" project, commissioned by The Friedman Foundation for Educational Choice and conducted by Braun Research Incorporated (BRI), measures Alaska registered voters' familiarity and views on a range of K-12 education issues and school choice reforms. The author and his colleagues report response…

Transport properties of Y1-xNdxCo2 compounds

NASA Astrophysics Data System (ADS)

Uchima, K.; Takeda, M.; Zukeran, C.; Nakamura, A.; Arakaki, N.; Komesu, S.; Takaesu, Y.; Hedo, M.; Nakama, T.; Yagasaki, K.; Uwatoko, Y.; Burkov, A. T.

2012-12-01

Electrical resistivity ρ and thermopower S of light rare earth-based pseudo-binary Y1-xNdxCo2 alloys have been measured at temperatures from 2 K to 300 K and under pressures up to 3.5 GPa. The Curie temperature of the alloys, TC, determined from characteristic features in the temperature dependences of the transport properties, decreases with decreasing Nd concentration x and vanishes around xc = 0.3. The residual resistivity has a pronounced maximum at x = xc. The temperature coefficient of thermopower dS/dT at low temperature limit shows a complex dependence on alloy composition: it changes its sign from negative to positive at x ≍ 0.2, having a maximum at x = xc, and is nearly composition independent at x > 0.5. The pressure dependences of TC and ρ0 of Yo.6Ndo.4Co2 reveal the behavior similar to that observed in the Y1-xRxHCo2 (RH = heavy rare earth) alloy systems, which implies that the magnetic state of the Co-3d electron subsystem is responsible for the transport properties in the Y1-xNdxCo2 alloys.

Monitoring platelet inhibition after clopidogrel with the VerifyNow-P2Y12(R) rapid analyzer: the VERIfy Thrombosis risk ASsessment (VERITAS) study.

PubMed

Malinin, Alex; Pokov, Alex; Spergling, Malcolm; Defranco, Anthony; Schwartz, Kenneth; Schwartz, Dianne; Mahmud, Ehtisham; Atar, Dan; Serebruany, Victor

2007-01-01

Clopidogrel inhibits platelet P2Y12 ADP receptors, while ADP, as an inductor of aggregation, stimulates both P2Y12 and P2Y1 platelet receptors. Despite a clinical loading dose routine with clopidogrel, some patients still experience coronary stent thrombosis suggesting persistent platelet activation. The VerifyNow-P2Y12 is a rapid assay that test platelet activity over 3 min and uses of the combination of ADP and prostaglandin E1 (PGE1) to directly measure the effects of clopidogrel on the P2Y12 receptor. ADP is used to maximally activate the platelets by binding to the P2Y1 and P2Y12 platelet receptors, while PGE1 is used to suppress the ADP-induced P2Y1-mediated increase in intracellular calcium levels. The VERIfy Thrombosis risk ASsessment (VERITAS) was a prospective study designed to measure platelet response to clopidogrel therapy in subjects with multiple risk factors or history of vascular disease using this novel point-of-care assay. 166 participants were enrolled in 4 participating sites. Data from 147 participants were analyzed after exclusion of 19 patients due to protocol violations. Platelets were assessed twice at baseline (before clopidogrel) and at 24 h post-loading 450 mg (110 participants) or 7 days after chronic clopidogrel treatment (75 mg/day) (37 patients). All participants received aspirin 81-325 mg for at least 2 days before the study enrollment. Results from the VerifyNow-P2Y12 assay are reported in P2Y12 reaction units (PRU). Clopidogrel therapy resulted in a mean 64.0+/-25.3% PRU reduction. No participant reached PRU inhibition below 10% of baseline. Distribution of PRU values for the VerifyNow-P2Y12 assay shows a separation from baseline to post-clopidogrel assay values with some overlap due to high inter-individual variations in response. VerifyNow-P2Y12 is a reliable, fast and sensitive device suitable for monitoring of platelet inhibition during clopidogrel therapy.

Phase Competition in the Palmer-Chalker X Y Pyrochlore Er2Pt2O7

NASA Astrophysics Data System (ADS)

Hallas, A. M.; Gaudet, J.; Butch, N. P.; Xu, Guangyong; Tachibana, M.; Wiebe, C. R.; Luke, G. M.; Gaulin, B. D.

2017-11-01

We report neutron scattering measurements on Er2Pt2O7 , a new addition to the X Y family of frustrated pyrochlore magnets. Symmetry analysis of our elastic scattering data shows that Er2Pt2O7 orders into the k =0 , Γ7 magnetic structure (the Palmer-Chalker state), at TN=0.38 K . This contrasts with its sister X Y pyrochlore antiferromagnets Er2Ti2O7 and Er2Ge2O7 , both of which order into Γ5 magnetic structures at much higher temperatures, TN=1.2 and 1.4 K, respectively. In this temperature range, the magnetic heat capacity of Er2Pt2O7 contains a broad anomaly centered at T*=1.5 K . Our inelastic neutron scattering measurements reveal that this broad heat capacity anomaly sets the temperature scale for strong short-range spin fluctuations. Below TN=0.38 K , Er2Pt2O7 displays a gapped spin-wave spectrum with an intense, flat band of excitations at lower energy and a weak, diffusive band of excitations at higher energy. The flat band is well described by classical spin-wave calculations, but these calculations also predict sharp dispersive branches at higher energy, a striking discrepancy with the experimental data. This, in concert with the strong suppression of TN, is attributable to enhanced quantum fluctuations due to phase competition between the Γ7 and Γ5 states that border each other within a classically predicted phase diagram.

Project W-211 initial tank retrieval systems year 2000 compliance assessment project plan

DOE Office of Scientific and Technical Information (OSTI.GOV)

BUSSELL, J.H.

1999-08-24

This assessment describes the potential Year 2000 (Y2K) problems and describes the methods for achieving Y2K Compliance for Project W-211, Initial Tank Retrieval Systems (ITRS). The purpose of this assessment is to give an overview of the project. This document will not be updated and any dates contained in this document are estimates and may change. The scope of project W-211 is to provide systems for retrieval of radioactive wastes from ten double-shell tanks (DST). systems will be installed in tanks 102-AP, 104-AP, 105-AN, 104-AN, 102-AZ, 101-AW, 103-AN, 107-AN, 102-AY, and 102-SY. The current tank selection and sequence supports phasemore » I feed delivery to privatized processing plants. A detailed description of system dates, functions, interfaces, potential Y2K problems, and date resolutions can not be described since the project is in the definitive design phase. This assessment will describe the methods, protocols, and practices to assure that equipment and systems do not have Y2K problems.« less

The construction of space-like surfaces with k1k2 - m(k1 + k2) = 1 in Minkowski three-space

NASA Astrophysics Data System (ADS)

Cao, Xi-Fang

2002-07-01

From solutions of the sinh-Laplace equation, we construct a family of space-like surfaces with k1k2 - m(k1 + k2) = 1 in Minkowski three-space, where k1 and k2 are principal curvatures and m is an arbitrary constant.

Persistence of weight loss and acquired behaviors 2 y after stopping a 2-y calorie restriction intervention.

PubMed

Marlatt, Kara L; Redman, Leanne M; Burton, Jeff H; Martin, Corby K; Ravussin, Eric

2017-04-01

Background: Calorie restriction (CR) influences aging processes and extends average and maximal life spans. The CALERIE 2 (Comprehensive Assessment of Long-Term Effects of Reducing Intake of Energy Phase 2) study was the first randomized clinical trial to examine the metabolic and psychological effects of CR in nonobese humans. Objective: We conducted a 2-y follow-up study of adults who underwent 2 y of CR or ad libitum (control) consumption and determined whether weight loss and acquired behaviors persisted after the study ended when participants determined their own lifestyle behaviors. Design: In this prospective, longitudinal study, we assessed differences in weight, body composition, psychological function, and energy expenditure in 39 nonobese [body mass index (in kg/m 2 ): 22-28] men and women (25% CR: n = 24; control: n = 15) 12 and 24 mo after they completed the CALERIE 2 study at Pennington Biomedical. Results: Of 39 participants who were in the follow-up study, 29 subjects (CR: n = 18; control: n = 11) completed all visits at follow-up months 12 and 24. After the CR intervention, a mean ± SEM weight loss of 9.0 ± 0.6 kg was observed in the CR group, in which only 54% of the weight was regained 2 y later. Despite such a regain, weight, the percentage of body fat, and fat mass remained significantly reduced from baseline throughout follow-up and remained significantly less than in the control group ( P < 0.05). At follow-up, the CR group retained higher degrees of dietary restraint and avoidance of certain foods. Conclusion: After a 2-y intensive CR intervention, ∼50% of CR-induced weight loss was maintained 2 y later, which was probably the result of lasting effects on acquired behaviors and dietary restraint. This trial was registered at clinicaltrials.gov as NCT00943215. © 2017 American Society for Nutrition.

2007 Survey on External Support for K-12 Schools and Districts

ERIC Educational Resources Information Center

Pawlowski, Brett

2007-01-01

This preliminary survey offers insights into how community-school partnerships are structured and what types of relationships schools and districts have established. Among respondents to this survey, businesses and parent organizations are by far the most frequent K-12 partners. Also, clear differences were found in the responses of suburban,…

Delaware K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper No. 21

ERIC Educational Resources Information Center

DiPerna, Paul

2014-01-01

The "Delaware K-12 & School Choice Survey" project, commissioned by the Friedman Foundation for Educational Choice and conducted by Braun Research, Inc. (BRI), measures Delaware registered voters' familiarity and views on a range of K-12 education topics and school choice reforms. The author and his colleagues report response levels…

Nevada K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper No. 22

ERIC Educational Resources Information Center

DiPerna, Paul

2015-01-01

The "Nevada K-12 & School Choice Survey" project, commissioned by the Friedman Foundation for Educational Choice and conducted by Braun Research, Inc. (BRI), measures Nevada registered voters' familiarity and views on a range of K-12 education topics and school choice reforms. The author and his colleagues report response levels and…

Maine K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper Number 12

ERIC Educational Resources Information Center

DiPerna, Paul

2013-01-01

The "Maine K-12 & School Choice Survey" project, commissioned by the Friedman Foundation for Educational Choice and conducted by Braun Research, Inc. (BRI), measures Maine registered voters' familiarity and views on a range of K-12 education topics and school choice reforms. The author and his colleagues report response levels and…

Texas K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper Number 14

ERIC Educational Resources Information Center

DiPerna, Paul

2013-01-01

The "Texas K-12 & School Choice Survey" project, commissioned by the Friedman Foundation for Educational Choice and conducted by Braun Research, Inc. (BRI), measures Texas registered voters' familiarity and views on a range of K-12 education topics and school choice reforms. The author and his colleagues report response levels and…

Missouri K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper No. 19

ERIC Educational Resources Information Center

DiPerna, Paul

2014-01-01

The "Missouri K-12 & School Choice Survey" project, commissioned by the Friedman Foundation for Educational Choice and conducted by Braun Research, Inc. (BRI), measures Missouri registered voters' familiarity and views on a range of K-12 education topics and school choice reforms. The author and his colleagues report response levels…

Oklahoma K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper No. 18

ERIC Educational Resources Information Center

DiPerna, Paul

2014-01-01

The "Oklahoma K-12 & School Choice Survey" project, commissioned by the Friedman Foundation for Educational Choice and conducted by Braun Research, Inc. (BRI), measures Oklahoma registered voters' familiarity and views on a range of K-12 education topics and school choice reforms. The author and his colleagues report response levels…

Montana K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper Number 10

ERIC Educational Resources Information Center

DiPerna, Paul

2012-01-01

The "Montana K-12 & School Choice Survey" project, commissioned by the Friedman Foundation for Educational Choice and conducted by Braun Research, Inc. (BRI), measures Montana registered voters' familiarity and views on a range of K-12 education topics and school choice reforms. The author and his colleagues report response levels…

Louisiana K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper Number 7

ERIC Educational Resources Information Center

DiPerna, Paul

2012-01-01

The "Louisiana K-12 & School Choice Survey" project, commissioned by the Friedman Foundation for Educational Choice and conducted by Braun Research Incorporated (BRI), measures Louisiana registered voters' familiarity and views on a range of K-12 education topics and school choice reforms. In this paper the author and his colleagues…

Tennessee K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper Number 9

ERIC Educational Resources Information Center

DiPerna, Paul

2012-01-01

The "Tennessee K-12 & School Choice Survey" project, commissioned by the Friedman Foundation for Educational Choice and conducted by Braun Research Inc. (BRI), measures Tennessee registered voters' familiarity and views on a range of K-12 education topics and school choice reforms. The author and his colleagues report response levels…

Raman spectroscopy of KxCo2-ySe2 single crystals near the ferromagnet-paramagnet transition

DOE PAGES

Opacic, M.; Lazarevic, N.; Radonjic, M. M.; ...

2016-10-05

Polarized Raman scattering spectra of the K xCo 2-ySe 2 (x = :::; y = :::) single crystals reveal the presence of two phonon modes, assigned as of the A1g and B1g symmetry. Absence of additional modes excludes the possibility of vacancy ordering, unlike in K xCo 2-ySe 2 . The ferromagnetic (FM) phase transition at Tc 74 K leaves a clear fingerprint on the temperature dependence of the Raman mode energy and linewidth. For T > Tc the temperature dependence looks conventional, driven by the thermal expansion and anharmonicity. The Raman modes are rather broad due to the electron-phononmore » coupling increased by the disorder and spin fluctuation e ects. In the FM phase the phonon frequency of both modes increases, while an opposite trend is seen in their linewidth: the A1g mode narrows in the FM phase, whereas the B 1g mode broadens. We argue that the large asymmetry and anomalous frequency shift of the B 1g mode is due to the coupling of spin fluctuations and vibration. Our density functional theory (DFT) calculations for the phonon frequencies agree rather well with the Raman measurements, with some discrepancy being expected since the DFT calculations neglect the spin fluctuations.« less

CO adsorption on N2-precovered NaY faujasite: a FTIR analysis of the resulting adsorbed species.

PubMed

Cairon, Olivier

2013-08-26

To productively complete the information regarding the reversible adsorption of a gas mixture on the micropores of cationic zeolites, the adsorption of the two gases N2 and CO on NaY faujasite is taken as a model case study. We analyze herein CO adsorption (77 K) on two distinct N2-precovered NaY sets (low and medium). We outline the continuous desorption of N2 adducts during CO admittance to full N2 desorption for the highest CO loadings. These features contrast with preceding results obtained for N2 loading on CO-precovered NaY. By comparing these results with the sole CO admission and combining both studies regarding the co-adsorption sets, we demonstrate the influence of the basic strength of the two gases regarding the nature of the surface-adsorbed species formed. We also propose and discuss a hypothesis regarding the formation of adsorbed mixed species having both N2 and CO as ligands. These new findings strengthen the statistical response of IR signatures as a helpful proposal for analyzing adsorbed species and their assignments. This survey completes the molecular understanding of gas-mixture adsorption that lacks experimental data to date. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fragile singlet ground-state magnetism in the pyrochlore osmates R 2 Os 2 O 7 ( R = Y and Ho)

DOE PAGES

Zhao, Z. Y.; Calder, S.; Aczel, A. A.; ...

2016-04-25

The singlet ground state magnetism in pyrochlore osmates Y 2Os 2O 7 and Ho 2Os 2O 7 is studied by DC and AC susceptibility, specific heat, and neutron powder diffraction measurements. Despite the expected non-magnetic singlet in the strong spin-orbit coupling (SOC) limit for Os 4+ (5d 4), Y 2Os 2O 7 exhibits a spin-glass (SG) ground state below 4 K with weak magnetism, suggesting possible proximity to a quantum phase transition between the non-magnetic state in the strong SOC limit and the magnetic state in the strong superexchange limit. Ho 2Os 2O 7 has the same structural distortion asmore » occurs in Y 2Os 2O 7. However, the Os sublattice in Ho 2Os 2O 7 shows long- range magnetic ordering below 36 K. We find that the sharp difference of the magnetic ground state between Y 2Os 2O 7 and Ho 2Os 2O 7 signals the singlet ground state magnetism in R 2 Os 2 O 7 is fragile and can be disturbed by the weak 4f—5d interactions.« less

Fragile singlet ground-state magnetism in the pyrochlore osmates R 2 Os 2 O 7 ( R = Y and Ho)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Z. Y.; Calder, S.; Aczel, A. A.

The singlet ground state magnetism in pyrochlore osmates Y 2Os 2O 7 and Ho 2Os 2O 7 is studied by DC and AC susceptibility, specific heat, and neutron powder diffraction measurements. Despite the expected non-magnetic singlet in the strong spin-orbit coupling (SOC) limit for Os 4+ (5d 4), Y 2Os 2O 7 exhibits a spin-glass (SG) ground state below 4 K with weak magnetism, suggesting possible proximity to a quantum phase transition between the non-magnetic state in the strong SOC limit and the magnetic state in the strong superexchange limit. Ho 2Os 2O 7 has the same structural distortion asmore » occurs in Y 2Os 2O 7. However, the Os sublattice in Ho 2Os 2O 7 shows long- range magnetic ordering below 36 K. We find that the sharp difference of the magnetic ground state between Y 2Os 2O 7 and Ho 2Os 2O 7 signals the singlet ground state magnetism in R 2 Os 2 O 7 is fragile and can be disturbed by the weak 4f—5d interactions.« less

Origin of Pressure-induced Superconducting Phase in K xFe 2-ySe 2 studied by Synchrotron X-ray Diffraction and Spectroscopy

DOE PAGES

Yamamoto, Yoshiya; Yamaoka, Hitoshi; Tanaka, Masashi; ...

2016-08-08

Pressure dependence of the electronic and crystal structures of K xFe 2–ySe 2, which has pressure-induced two superconducting domes of SC I and SC II, was investigated by x-ray emission spectroscopy and diffraction. X-ray diffraction data show that compressibility along the c-axis changes around 12 GPa, where a new superconducting phase of SC II appears. This suggests a possible tetragonal to collapsed tetragonal phase transition. X-ray emission spectroscopy data also shows the change in the electronic structure around 12 GPa. These results can be explained by the scenario that the two SC domes under pressure originate from the change ofmore » Fermi surface topology. Lastly, our results here show the pronounced increase of the density of states near the Fermi surface under pressure with a structural phase transition, which can help address our fundamental understanding for the appearance of the SC II phase.« less

Indiana K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper No. 27

ERIC Educational Resources Information Center

DiPerna, Paul

2016-01-01

The purpose of the "Indiana K-12 & School Choice Survey" is to measure public opinion on, and in some cases awareness or knowledge of, a range of K-12 education topics and school choice reforms. The Friedman Foundation for Educational Choice developed this project in partnership with Braun Research, Inc., who conducted the live phone…

Space Mission : Y3K

NASA Astrophysics Data System (ADS)

2001-01-01

ESA and the APME are hosting a contest for 10 - 15 year olds in nine European countries (Austria, Belgium, France, Germany, Italy, the Netherlands, Spain, Sweden and the United Kingdom). The contest is based on an interactive CD ROM, called Space Mission: Y3K, which explores space technology and shows some concrete uses of that technology in enhancing the quality of life on Earth. The CD ROM invites kids to join animated character Space Ranger Pete on an action-packed, colourful journey through space. Space Ranger Pete begins on Earth: the user navigates around a 'locker room' to learn about synthetic materials used in rocket boosters, heat shields, space suits and helmets, and how these materials have now become indispensable to everyday life. From Earth he flies into space and the user follows him from the control room in the spacecraft to a planet, satellites and finally to the International Space Station. Along the way, the user jots down clues that he or she discovers in this exploration, designing an imaginary space community and putting together a submission for the contest. The lucky winners will spend a weekend training as "junior astronauts" at the European Space Centre in Belgium (20-22 April 2001). They will be put through their astronaut paces, learning the art of space walking, running their own space mission, piloting a space capsule and re-entering the Earth's atmosphere. The competition features in various youth media channels across Europe. In the UK, popular BBC Saturday morning TV show, Live & Kicking, will be launching the competition and will invite viewers to submit their space community designs to win a weekend at ESC. In Germany, high circulation children's magazine Geolino will feature the competition in the January issue and on their internet site. And youth magazine ZoZitDat will feature the competition in the Netherlands throughout February. Space Mission: Y3K is part of an on-going partnership between the ESA's Technology Transfer

Effect of vitamin K2 on type 2 diabetes mellitus: A review.

PubMed

Li, Yan; Chen, Jie Peng; Duan, Lili; Li, Shuzhuang

2018-02-01

Type 2 diabetes mellitus (T2DM) continue to be a major public health problem around the world that frequently presents with microvascular and macrovascular complications. Individuals with T2DM are not only suffering from significant emotional and physical misery, but also at increased risk of dying from severe complications. In recent years, evidence from prospective observational studies and clinical trials has shown T2DM risk reduction with vitamin K2 supplementation. We thus did an overview of currently available studies to assess the effect of vitamin K2 supplementation on insulin sensitivity, glycaemic control and reviewed the underlying mechanisms. We proposed that vitamin K2 improved insulin sensitivity through involvement of vitamin K-dependent-protein osteocalcin, anti-inflammatory properties, and lipid-lowering effects. Vitamin K2 had a better effect than vitamin K1 on T2DM. The interpretation of this review will increase comprehension of the development of a therapeutic strategy to prevent and treat T2DM. Copyright © 2017 Elsevier B.V. All rights reserved.

1. Historic American Buildings Survey Everitt K. Taylor, Photographer September ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Historic American Buildings Survey Everitt K. Taylor, Photographer September 15, 1936 EXTERIOR - GENERAL VIEW EAST ELEVATION FROM OLD PRINT IN POSSESSION OF OWNER - Governor's House, 149 Kearny Avenue, Perth Amboy, Middlesex County, NJ

Radiation-induced amorphization of Ce-doped Mg2Y8(SiO4)6O2 silicate apatite

NASA Astrophysics Data System (ADS)

Zhou, Jianren; Yao, Tiankai; Lian, Jie; Shen, Yiqiang; Dong, Zhili; Lu, Fengyuan

2016-07-01

Ce-doped Mg2Y8(SiO4)6O2 silicate apatite (Ce = 0.05 and 0.5) were irradiated with 1 MeV Kr2+ ion beam irradiation at different temperatures and their radiation response and the cation composition dependence of the radiation-induced amorphization were studied by in situ TEM. The two Ce-doped Mg2Y8(SiO4)6O2 silicate apatites are sensitive to ion beam induced amorphization with a low critical dose (0.096 dpa) at room temperature, and exhibits significantly different radiation tolerance at elevated temperatures. Ce concentration at the apatite AI site plays a critical role in determining the radiation response of this silicate apatite, in which the Ce3+ rich Mg2Y7.5Ce0.5(SiO4)6O2 displays lower amorphization susceptibility than Mg2Y7.95Ce0.05(SiO4)6O2 with a lower Ce3+ occupancy at the AI sites. The critical temperature (Tc) and activation energy (Ea) change from 667.5 ± 33 K and 0.162 eV of Mg2Y7.5Ce0.5(SiO4)6O2 to 963.6 ± 64 K and 0.206 eV of Mg2Y7.95Ce0.05(SiO4)6O2. We demonstrate that the radiation tolerance can be controlled by varying the chemical composition, and enhanced radiation tolerance is achieved by increasing the Ce concentration at the AI site.

Synthetic and spectroscopic studies of vanadate glaserites I: Upconversion studies of doubly co-doped (Er, Tm, or Ho):Yb:K{sub 3}Y(VO{sub 4}){sub 2}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kimani, Martin M., E-mail: kimani@g.clemson.edu; Chen, Hongyu, E-mail: hongyuc@g.clemson.edu; McMillen, Colin D., E-mail: cmcmill@g.clemson.edu

2015-03-15

The synthesis and upconversion properties of trigonal glaserite-type K{sub 3}Y(VO{sub 4}){sub 2} co-doped with Er{sup 3+}/Yb{sup 3+}, Ho{sup 3+}/Yb{sup 3+}, or Tm{sup 3+}/Yb{sup 3+} were studied. Powder samples were synthesized by solid state reactions at 1000 °C for 48 h, while well-formed hexagonal single crystals of the same were grown hydrothermally using 10 M K{sub 2}CO{sub 3} at 560–650 °C. Infrared-to-visible upconversion by Er{sup 3+}/Yb{sup 3+}, Ho{sup 3+}/Yb{sup 3+}, or Tm{sup 3+}/Yb{sup 3+} codoped-K{sub 3}Y(VO{sub 4}){sub 2} glaserite powder and single crystals was observed, and the upconversion spectral properties were studied as a function of different Er{sup 3+}, Tm{sup 3+},more » Ho{sup 3+}, and Yb{sup 3+} ion concentrations. The process is observed under 980 nm laser diode excitation and leads to strong green (552 nm) and red (659 nm) emission for Er{sup 3+}/Yb{sup 3+}, green (549 nm) and red (664 nm) emission for Ho{sup 3+}/Yb{sup 3+}, and blue (475 nm) and red (647 nm) emission for Tm{sup 3+}/Yb{sup 3+}. The main mechanism that allows for up-conversion is attributed the energy transfer among Yb{sup 3+} and the various Er{sup 3+}/Ho{sup 3+}/Tm{sup 3+} ions in excited states. These results illustrate the large potential of co-doped alkali double vanadates for photonic applications involving optoelectronics devices. - Graphical abstract: Synthesis and upconversion in vanadate glaserites. - Highlights: • K{sub 3}Y(VO{sub 4}){sub 2} codoped with Er, Tm, or Ho:Yb were synthesized via solid-state and hydrothermal routes. • Upconversion properties are investigated. • The codoped compounds revealed efficient infrared-to-visible upconversion. • The presented compounds are potential host for solid state lighting.« less

Irreversibility and critical current density of FeSr2ErCu2O6+y

NASA Astrophysics Data System (ADS)

Hata, Y.; Iida, I.; Mochiku, T.; Yasuoka, H.

2018-03-01

FeSr2ErCu2O6+y (ErFe1212) and non-superconducting FeSr2ErCu1.9Zn0.1O6+y were synthesized to study the property of the superconductivity and the irreversibility of ErFe1212. A large irreversibility in the temperature dependence of magnetization and a hysteresis in the magnetization curve were observed in ErFe1212. By comparison with non-superconducting FeSr2ErCu1.9Zn0.1O6+y, it was found that the most part of the hysteresis at high magnetic eld originates from the magnetism of Fe ion and some part of the hysteresis at low magnetic eld originates from the superconductivity. Using the magnetization curve of ErFe1212 and FeSr2ErCu1.9Zn0.1O6+y, the J c of ErFe1212 in individual grains at 10 K under 0.1 T was estimated by the Bean model and {J}\\text{c}\\text{intra} was 2.6 × 109 A/m2. The critical current density across inter-grain boundaries at 10 K estimated by V ‑ I measurement was {J}\\text{c}\\text{intra} = 5.7 × 104 A/m2. A large difference between {J}\\text{c}\\text{intra} and {J}\\text{c}\\text{intra} was observed in ErFe1212. {J}\\text{c}\\text{intra} and {J}\\text{c}\\text{intra} of ErFe1212 are 2.2 and 5.2 times larger than these of YFe1212, respectively.

[Assessment of a residency training program in endocrinology and nutrition by physicians: results of a survey].

PubMed

Moreno-Fernández, Jesús; Gutiérrez-Alcántara, Carmen; Palomares-Ortega, Rafael; García-Manzanares, Alvaro; Benito-López, Pedro

2011-12-01

The current training program for resident physicians in endocrinology and nutrition (EN) organizes their medical learning. Program evaluation by physicians was assessed using a survey. The survey asked about demographic variables, EN training methods, working time and center, and opinion on training program contents. Fifty-one members of Sociedad Castellano-Manchega de Endocrinología, Nutrición y Diabetes, and Sociedad Andaluza de Endocrinología y Nutrición completed the survey. Forty-percent of them disagreed with the compulsory nature of internal medicine, cardiology, nephrology and, especially, neurology rotations (60%); a majority (>50%) were against several recommended rotations included in the program. The fourth year of residence was considered by 37.8% of respondents as the optimum time for outpatient and inpatient control and monitoring without direct supervision. The recommended monthly number of on-call duties was 3.8±1.2. We detected a positive opinion about extension of residence duration to 4.4±0.5 years. Doctoral thesis development during the residence period was not considered convenient by 66.7% of physicians. Finally, 97.8% of resident physicians would recommend residency in EN to other colleagues. Endocrinologists surveyed disagreed with different training program aspects such as the rotation system, skill acquisition timing, and on-call duties. Therefore, an adaptation of the current training program in EN would be required. Copyright © 2011 SEEN. Published by Elsevier Espana. All rights reserved.

Rotational Mode Specificity in the F(-) + CH3Y [Y = F and Cl] SN2 Reactions.

PubMed

Szabó, István; Czakó, Gábor

2015-12-17

More than 12 million quasiclassical trajectories are computed for the F(-) + CH3Y(v = 0, JK) [Y = F and Cl] SN2 reactions using full-dimensional ab initio analytical potential energy surfaces. The initial (J, K = 0) and (J, K = J) [J = 0, 2, 4, 6, 8] rotational state specific cross sections are obtained at different collision energies (Ecoll) in the 1-20 kcal mol(-1) range, and the scattering angle and initial attack angle distributions as well as the mechanism-specific opacity functions are reported at Ecoll = 10 kcal mol(-1). The tumbling rotation (K = 0) inhibits the F(-) + CH3F reaction by a factor of 3 for J = 8 at Ecoll = 10 kcal mol(-1). This tumbling rotational effect becomes smaller at low and high Ecoll, and the tumbling motion affects the cross sections of F(-) + CH3Cl by only a few percent. The spinning rotation (K = J) hinders both reactions by factors in the 1.3-1.7 range for J = 8 at low Ecoll, whereas slight promotion is found as the Ecoll increases. The tumbling rotation may counteract the attractive ion-dipole forces, and the spinning motion hinders the complex formation, thereby decreasing the reactivity.

2. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. Historic American Buildings Survey Russell Jones, Photographer April 1959 REAR (NORTH) ELEVATION FROM THE N. W. - Southeast Area Survey, 600-602 & 1100 G Street (House), 1002,1006 Eye Street (House), 808-810,812-814, & 1016 K Street (House), 817-819 L Street (House), Washington, District of Columbia, DC

North Dakota K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper Number 13

ERIC Educational Resources Information Center

DiPerna, Paul

2013-01-01

The "North Dakota K-12 & School Choice Survey" project, commissioned by the Friedman Foundation for Educational Choice and conducted by Braun Research, Inc. (BRI), measures North Dakota registered voters' familiarity and views on a range of K-12 education topics and school choice reforms. The author and his colleagues report response…

New Mexico K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper Number 4

ERIC Educational Resources Information Center

DiPerna, Paul

2011-01-01

The "New Mexico K-12 & School Choice Survey" project, commissioned by The Friedman Foundation for Educational Choice and conducted by Braun Research Incorporated (BRI), measures New Mexico voters' familiarity and views on a range of K-12 education issues and school choice reforms. The author and his colleagues report response…

Emergence of superconductivity and magnetic ordering tuned by Fe-vacancy in alkali-metal Fe chalcogenides RbxFe2-ySe2

NASA Astrophysics Data System (ADS)

Kobayashi, Yoshiaki; Kototani, Shouhei; Itoh, Masayuki; Sato, Masatoshi

2014-12-01

Samples of RbxFe2-ySe2 exhibiting superconductivity [superconducting (SC) samples] undergo a phase-separation into two phases, a Fe-vacancy ordered phase with antiferromagnetic (AFM) transition at TN1~500 K (AFM1 phase) and a phase with little Fe- vacancy and SC transition at Tc~30 K (SC phase). The samples of RbxFe2-ySe2 exhibiting no SC behaviour (non-SC samples) are phase-separated into three phases, the AFM1 phase, another AFM phase with TN2 ~150 K (AFM2 phase), and a paramagnetic phase with no SC transitions (paramagnetic non-SC phase). In this paper, we present the experimental results of magnetic susceptibility, electrical resistivity, and NMR measurements on single crystals of RbxFe2-ySe2 to reveal physical properties of these co-existing phases in the SC and non-SC samples. The 87Rb and 77Se NMR spectra show that the Fe vacancy concentration is very small in the Fe planes of the SC phase, whereas the AFM2 and paramagnetic non-SC phases in non-SC samples have larger amount of Fe vacancies. The randomness induced by the Fe vacancy in the non-SC samples makes the AFM2 and paramagnetic non-SC phases insulating/semiconducting and magnetically active, resulting in the absence of the superconductivity in RbxFe2-ySe2.

Ultra high resolution imaging of the human head at 8 tesla: 2K x 2K for Y2K.

PubMed

Robitaille, P M; Abduljalil, A M; Kangarlu, A

2000-01-01

To acquire ultra high resolution MRI images of the human brain at 8 Tesla within a clinically acceptable time frame. Gradient echo images were acquired from the human head of normal subjects using a transverse electromagnetic resonator operating in quadrature and tuned to 340 MHz. In each study, a group of six images was obtained containing a total of 208 MB of unprocessed information. Typical acquisition parameters were as follows: matrix = 2,000 x 2,000, field of view = 20 cm, slice thickness = 2 mm, number of excitations (NEX) = 1, flip angle = 45 degrees, TR = 750 ms, TE = 17 ms, receiver bandwidth = 69.4 kHz. This resulted in a total scan time of 23 minutes, an in-plane resolution of 100 microm, and a pixel volume of 0.02 mm3. The ultra high resolution images acquired in this study represent more than a 50-fold increase in in-plane resolution relative to conventional 256 x 256 images obtained with a 20 cm field of view and a 5 mm slice thickness. Nonetheless, the ultra high resolution images could be acquired both with adequate image quality and signal to noise. They revealed numerous small venous structures throughout the image plane and provided reasonable delineation between gray and white matter. The elevated signal-to-noise ratio observed in ultra high field magnetic resonance imaging can be utilized to acquire images with a level of resolution approaching the histological level under in vivo conditions. However, brain motion is likely to degrade the useful resolution. This situation may be remedied in part with cardiac gating. Nonetheless, these images represent a significant advance in our ability to examine small anatomical features with noninvasive imaging methods.

K-2 "Make It Count" Students' Views of Mathematics

ERIC Educational Resources Information Center

Leder, Gilah; Forgasz, Helen

2012-01-01

Data from an attitude survey administered to students in grades K-2 from four schools participating in the "Make it Count" project are reported in this paper. Few differences were found in the attitudes and beliefs of the Indigenous and non-Indigenous participants. The relevance of these findings for students' longer term mathematics…

2. Historic American Buildings Survey, Nelson E. Baldwin, Photographer, Jan. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. Historic American Buildings Survey, Nelson E. Baldwin, Photographer, Jan. 16, 1937, View - Interior Door Opening into Apartment on First Floor, 123 North Pearl St., Albany, N.Y. - Old Homeopathic Hospital (Interiors), 123 North Pearl Street, Albany, Albany County, NY

Safety assessment of Cracked K-joint Structure Based on Fracture Mechanics

NASA Astrophysics Data System (ADS)

Wang, Xin; Pengyu, Yan; Jianwei, Du; Fuhai, Cai

2017-05-01

The K-joint is the main bearing structure of lattice jib crane. During frequent operation of the crane, surface cracks often occur at its weld toe, and then continue to expand until failure. The safety of the weak structure K-joint of the crane jib can be evaluated by BS7910 failure assessment standard in order to improve its utilization. The finite element model of K-joint structure with cracks is established, and its mechanical properties is analyzed by ABAQUS software, the results show that the crack depth has a great influence on the bearing capacity of the structure compared with the crack length. It is assumed that the K-joint with the semi-elliptical surface crack under the action of the tension propagate stably under the condition that the c/a (ratio of short axis to long axis of ellipse) is about 0.3. The safety assessment of K-joint with different lengths crack is presented according to the 2A failure assessment diagram of BS7910, and the critical crack of K-joint under different loads can be obtained.

Metal-organic framework: Structure and magnetic properties of [Cu3(BTC)2 (L)x·(CuO)y]n (L=H2O, DMF)

NASA Astrophysics Data System (ADS)

da Silva, Gilvaldo G.; Machado, F. L. A.; Junior, S. Alves; Padrón-Hernández, E.

2017-09-01

The compounds [Cu3(BTC)2(L)x·(CuO)y], with BTC (benzene 1,3,5-tricarboxylate) and L (H2O or DMF) were prepared using electrochemical synthesis. Structural and morphologic characterizations were performed by X-ray diffraction and scanning electronic microscopy. The [Cu3(BTC)2 (L)x·(CuO)y] contain dimeric [Cu2(O2CR)]4 units with three possible spin configurations arising from Cu(II) 3d9 states and Cu-Cu δ bond. We observed an unusual very strong antiferromagnetic coupling in temperatures ranging from 100 K to 350 K for [Cu3(BTC)2.(H2O)3. (CuO)y]n. The inverse susceptibility versus temperature shows a linearity from 20 K up to 65 K fitting the Curie-Weiss law, for L = DMF. The CW X-band electron paramagnetic resonance spectroscopy (EPR) was important to explore the coordination state for DMF in the network. It was observed that DMF is located in an equatorial geometry of the coordination network experimenting interactions from the nitrogen and copper ions.

Endogenous peptide YY and neuropeptide Y inhibit colonic ion transport, contractility and transit differentially via Y1 and Y2 receptors

PubMed Central

Tough, IR; Forbes, S; Tolhurst, R; Ellis, M; Herzog, H; Bornstein, JC; Cox, HM

2011-01-01

BACKGROUND AND PURPOSE Peptide YY (PYY) and neuropeptide Y (NPY) activate Y receptors, targets under consideration as treatments for diarrhoea and other intestinal disorders. We investigated the gastrointestinal consequences of selective PYY or NPY ablation on mucosal ion transport, smooth muscle activity and transit using wild-type, single and double peptide knockout mice, comparing mucosal responses with those from human colon. EXPERIMENTAL APPROACH Mucosae were pretreated with a Y1 (BIBO3304) or Y2 (BIIE0246) receptor antagonist and changes in short-circuit current recorded. Colonic transit and colonic migrating motor complexes (CMMCs) were assessed in vitro and upper gastrointestinal and colonic transit measured in vivo. KEY RESULTS Y receptor antagonists revealed tonic Y1 and Y2 receptor-mediated antisecretory effects in human and wild-type mouse colon mucosae. In both, Y1 tone was epithelial while Y2 tone was neuronal. Y1 tone was reduced 90% in PYY−/− mucosa but unchanged in NPY−/− tissue. Y2 tone was partially reduced in NPY−/− or PYY−/− mucosae and abolished in tetrodotoxin-pretreated PYY−/− tissue. Y1 and Y2 tone were absent in NPYPYY−/− tissue. Colonic transit was inhibited by Y1 blockade and increased by Y2 antagonism indicating tonic Y1 excitation and Y2 inhibition respectively. Upper GI transit was increased in PYY−/− mice only. Y2 blockade reduced CMMC frequency in isolated mouse colon. CONCLUSIONS AND IMPLICATIONS Endogenous PYY and NPY induced significant mucosal antisecretory tone mediated by Y1 and Y2 receptors, via similar mechanisms in human and mouse colon mucosa. Both peptides contributed to tonic Y2-receptor-mediated inhibition of colonic transit in vitro but only PYY attenuated upper GI transit. PMID:21457230

Mutation of A677 in histone methyltransferase EZH2 in human B-cell lymphoma promotes hypertrimethylation of histone H3 on lysine 27 (H3K27).

PubMed

McCabe, Michael T; Graves, Alan P; Ganji, Gopinath; Diaz, Elsie; Halsey, Wendy S; Jiang, Yong; Smitheman, Kimberly N; Ott, Heidi M; Pappalardi, Melissa B; Allen, Kimberly E; Chen, Stephanie B; Della Pietra, Anthony; Dul, Edward; Hughes, Ashley M; Gilbert, Seth A; Thrall, Sara H; Tummino, Peter J; Kruger, Ryan G; Brandt, Martin; Schwartz, Benjamin; Creasy, Caretha L

2012-02-21

Trimethylation of histone H3 on lysine 27 (H3K27me3) is a repressive posttranslational modification mediated by the histone methyltransferase EZH2. EZH2 is a component of the polycomb repressive complex 2 and is overexpressed in many cancers. In B-cell lymphomas, its substrate preference is frequently altered through somatic mutation of the EZH2 Y641 residue. Herein, we identify mutation of EZH2 A677 to a glycine (A677G) among lymphoma cell lines and primary tumor specimens. Similar to Y641 mutant cell lines, an A677G mutant cell line revealed aberrantly elevated H3K27me3 and decreased monomethylated H3K27 (H3K27me1) and dimethylated H3K27 (H3K27me2). A677G EZH2 possessed catalytic activity with a substrate specificity that was distinct from those of both WT EZH2 and Y641 mutants. Whereas WT EZH2 displayed a preference for substrates with less methylation [unmethylated H3K27 (H3K27me0):me1:me2 k(cat)/K(m) ratio = 9:6:1] and Y641 mutants preferred substrates with greater methylation (H3K27me0:me1:me2 k(cat)/K(m) ratio = 1:2:13), the A677G EZH2 demonstrated nearly equal efficiency for all three substrates (H3K27me0:me1:me2 k(cat)/K(m) ratio = 1.1:0.6:1). When transiently expressed in cells, A677G EZH2, but not WT EZH2, increased global H3K27me3 and decreased H3K27me2. Structural modeling of WT and mutant EZH2 suggested that the A677G mutation acquires the ability to methylate H3K27me2 through enlargement of the lysine tunnel while preserving activity with H3K27me0/me1 substrates through retention of the Y641 residue that is crucial for orientation of these smaller substrates. This mutation highlights the interplay between Y641 and A677 residues in the substrate specificity of EZH2 and identifies another lymphoma patient population that harbors an activating mutation of EZH2.

A Protocol for Advanced Psychometric Assessment of Surveys

PubMed Central

Squires, Janet E.; Hayduk, Leslie; Hutchinson, Alison M.; Cranley, Lisa A.; Gierl, Mark; Cummings, Greta G.; Norton, Peter G.; Estabrooks, Carole A.

2013-01-01

Background and Purpose. In this paper, we present a protocol for advanced psychometric assessments of surveys based on the Standards for Educational and Psychological Testing. We use the Alberta Context Tool (ACT) as an exemplar survey to which this protocol can be applied. Methods. Data mapping, acceptability, reliability, and validity are addressed. Acceptability is assessed with missing data frequencies and the time required to complete the survey. Reliability is assessed with internal consistency coefficients and information functions. A unitary approach to validity consisting of accumulating evidence based on instrument content, response processes, internal structure, and relations to other variables is taken. We also address assessing performance of survey data when aggregated to higher levels (e.g., nursing unit). Discussion. In this paper we present a protocol for advanced psychometric assessment of survey data using the Alberta Context Tool (ACT) as an exemplar survey; application of the protocol to the ACT survey is underway. Psychometric assessment of any survey is essential to obtaining reliable and valid research findings. This protocol can be adapted for use with any nursing survey. PMID:23401759

Study of MoVO(y) (y = 2-5) anion and neutral clusters using anion photoelectron spectroscopy and density functional theory calculations.

PubMed

Mann, Jennifer E; Rothgeb, David W; Waller, Sarah E; Jarrold, Caroline Chick

2010-10-28

The vibrationally resolved anion photoelectron (PE) spectra of MoVO(y)(-) (y = 2 - 5) metal suboxide clusters are presented and analyzed in the context of density functional theory (DFT) calculations. The electronically congested spectra reflect an increase in cluster electron affinity with increasing oxidation state. Ion beam hole-burning results reveal the features in the PE spectra of MoVO(2)(-) and MoVO(4)(-) are a result of only one anion isomer, while at least two isomers contribute to electronic structure observed in the PE spectrum of MoVO(3)(-). Spectral features of the binary systems are compared to their pure analogs, Mo(2)O(y) and V(2)O(y). An attempt to characterize the anion and neutral electronic and molecular structures is made by comparison with results from DFT calculations. However, reconciliation between the cluster spectra and the calculated spectroscopic parameters is not as straightforward as in previous studies on similar systems (Yoder, B. L.; Maze, J. T.; Raghavachari, K.; Jarrold, C. C. J. Chem. Phys. 2005, 122, 094313 and Mayhall, N. J.; Rothgeb, D. W.; Hossain, E.; Raghavachari, K.; Jarrold, C. C. J. Chem. Phys. 2009, 130, 124313).

Virginia's Opinion on K-12 Education and School Choice. School Choice Survey in the State

ERIC Educational Resources Information Center

DiPerna, Paul

2009-01-01

This statistically representative survey of 1,203 likely Virginia voters illustrates public opinion on a wide range of K-12 education issues. The underlying purpose of the Friedman Foundation's state surveys is to measure voter knowledge and attitudes toward public institutions and policies, innovative ideas, and the state's K-12 education system.…

12 CFR 8.2 - Semiannual assessment.

Code of Federal Regulations, 2011 CFR

2011-01-01

... over— The semiannual assessment is: This amount—base amount Plus marginal rates Of excess over— Column A Column B Column C Column D Column E Million Million Million $0 $2 $X1 0 2 20 X2 Y1 $2 20 100 X3 Y2... national bank falls into one of the asset-size brackets denoted by Columns A and B. A bank's semiannual...

Semen says: Assessing the accuracy of adolescents’ self-reported sexual abstinence using a semen Y-chromosome biomarker

PubMed Central

Rosenbaum, Janet E.; Zenilman, Jonathan M.; Rose, Eve; Wingood, Gina M.; DiClemente, Ralph J.

2016-01-01

Objective Researchers often assess condom use only among participants who report recent sexual behaviour, excluding participants who report no recent vaginal sex or who did not answer questions about their sexual behaviour, but self-reported sexual behaviour may be inaccurate. This study uses a semen Y-chromosome biomarker to assess semen exposure among participants who reported sexual abstinence or did not report their sexual behaviour. Methods This prospective cohort study uses data from 715 sexually active African-American female adolescents in Atlanta, surveyed at baseline, 6 months, and 12 months. Participants completed a 40-minute interview and were tested for semen Y-chromosome with polymerase chain reaction from a self-administered vaginal swab. We predicted Y-chromosome test results from self-reported sexual behaviour using within-subject panel regression. Results Among participants who reported abstinence from vaginal sex in the past 14 days, 9.4% tested positive for semen Y-chromosome. Among item non-respondents, 6.3% tested positive for semen Y-chromosome. Women who reported abstinence and engaged in item non-response regarding their sexual behaviour had respectively 62% and 78% lower odds of testing positive for Y-chromosome (OR 0.38 (0.21, 0.67), OR 0.22 (0.12, 0.40)), controlling for smoking, survey wave, and non-coital sexual behaviours reported during abstinence. Conclusions Adolescents who report sexual abstinence under-report semen exposure. Research should validate self-reported sexual behaviour with biomarkers. Adolescents who engage in item non-response regarding vaginal sex test positive for semen Y-chromosome at similar rates, which supports the practice of grouping non-respondents with adolescents reporting abstinence in statistical analysis. PMID:27147615

2. Historic American Buildings Survey Albert S. Burns, Photographer C. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. Historic American Buildings Survey Albert S. Burns, Photographer C. 1934, 1935 COPY OF PRINT LOANED BY MR. POLLEN JEWETT, NYACK, N.Y. TAKEN ABOUT 1900 VIEW ACROSS ROCK CREEK - Pierce Mill, Tilden Street & Beach Drive Northwest, Washington, District of Columbia, DC

Photoluminescence, thermoluminescence glow curve and emission characteristics of Y2O3:Er3 + nanophosphor

NASA Astrophysics Data System (ADS)

N. J., Shivaramu; B. N., Lakshminarasappa; K. R., Nagabhushana; H. C., Swart; Fouran, Singh

2018-01-01

Nanocrystalline Er3 + doped Y2O3crystals were prepared by a sol gel technique. X-ray diffraction (XRD) patterns showed the cubic structure of Y2O3 and the crystallite size was found to be 25 nm. Optical absorption showed absorption peaks at 454, 495 and 521 nm. These peaks are attributed to the 4F3/2 + 4F5/2, 4F7/2 and 2H11/2 + 4S3/2 transitions of Er3 +. Under excitation at 378 nm, the appearance of strong green (520-565 nm) down conversion emission assigned to the (2H11/2,4S3/2) → 4I15/2 transition and the feeble red (650-665 nm) emission is assigned to the 4F9/2 → 4I15/2 transition. The color chromaticity coordinates showed emission in the green region. The strong green emission of Y2O3:Er3 + nanophosphor may be useful for applications in solid compact laser devices. Thermoluminescence (TL) studies of γ-irradiated Y2O3:Er3 + showed a prominent TL glow peak maximum at 383 K along with a less intense shoulder peak at 425 K and a weak glow at 598 K. TL emission peaks with maxima at 545, 490, 588 and 622 nm for the doped sample were observed at a temperature of 383 K and these emissions were due to defect related to the host material. TL kinetic parameters were calculated by a glow curve deconvolution (GCD) method and the obtained results are discussed in detail for their possible usage in high dose dosimetry.

A687V EZH2 is a driver of histone H3 lysine 27 (H3K27) hypertrimethylation.

PubMed

Ott, Heidi M; Graves, Alan P; Pappalardi, Melissa B; Huddleston, Michael; Halsey, Wendy S; Hughes, Ashley M; Groy, Arthur; Dul, Edward; Jiang, Yong; Bai, Yuchen; Annan, Roland; Verma, Sharad K; Knight, Steven D; Kruger, Ryan G; Dhanak, Dashyant; Schwartz, Benjamin; Tummino, Peter J; Creasy, Caretha L; McCabe, Michael T

2014-12-01

The EZH2 methyltransferase silences gene expression through methylation of histone H3 on lysine 27 (H3K27). Recently, EZH2 mutations have been reported at Y641, A677, and A687 in non-Hodgkin lymphoma. Although the Y641F/N/S/H/C and A677G mutations exhibit clearly increased activity with substrates dimethylated at lysine 27 (H3K27me2), the A687V mutant has been shown to prefer a monomethylated lysine 27 (H3K27me1) with little gain of activity toward H3K27me2. Herein, we demonstrate that despite this unique substrate preference, A687V EZH2 still drives increased H3K27me3 when transiently expressed in cells. However, unlike the previously described mutants that dramatically deplete global H3K27me2 levels, A687V EZH2 retains normal levels of H3K27me2. Sequencing of B-cell-derived cancer cell lines identified an acute lymphoblastic leukemia cell line harboring this mutation. Similar to exogenous expression of A687V EZH2, this cell line exhibited elevated H3K27me3 while possessing H3K27me2 levels higher than Y641- or A677-mutant lines. Treatment of A687V EZH2-mutant cells with GSK126, a selective EZH2 inhibitor, was associated with a global decrease in H3K27me3, robust gene activation, caspase activation, and decreased proliferation. Structural modeling of the A687V EZH2 active site suggests that the increased catalytic activity with H3K27me1 may be due to a weakened interaction with an active site water molecule that must be displaced for dimethylation to occur. These findings suggest that A687V EZH2 likely increases global H3K27me3 indirectly through increased catalytic activity with H3K27me1 and cells harboring this mutation are highly dependent on EZH2 activity for their survival. ©2014 American Association for Cancer Research.

Radioluminescence as a function of temperature and low temperature thermoluminescence of BaY2F8:Ce and BaY2F8:Nd crystals

NASA Astrophysics Data System (ADS)

Kowalski, Z.; Kaczmarek, S. M.; Brylew, K.; Drozdowski, W.

2016-09-01

Radioluminescence spectra at temperatures ranging from 10 to 320 K and low temperature thermoluminescence glow curves of BaY2F8:Ce and BaY2F8:Nd scintillator crystals have been investigated. In both materials the intensities of the excitonic and the activator ion's emission at X-ray excitation vary with temperature, anticorrelating with each other, which provides valuable information on the host-to-ion energy transfer. Detailed thermoluminescence studies, in turn, prove the existence of charge traps, which introduce quasi-continuous distributions of energy levels into the bandgap.

Vaporization thermodynamics of K2S and K2SO3

NASA Technical Reports Server (NTRS)

Bennet, J. E.

1982-01-01

The vaporization reactions, vapor pressures, and thermodynamics of potassium sulfide and potassium sulfite were studied for purposes of providing fundamental data for the seed cycle in magnetohydrodynamic electric power generation. Rate of effusion studies, supported by tube furnace experiments, X-ray powder diffraction, mass spectrometry and appropriate chemical analyses and tests, revealed that potassium sulfite disproportionates at high temperatures to form potassium sulfide and potassium sulfate. Potassium sulfide was observed to vaporize incongruently, the initial vapors beng predominantly potassium atoms, with minor species being S2 and various K-S molecules. The ratio of K/S2 in the vapor is very large initially and decreases steadily with prolonged heating. Several materials were evaluated for purposes of containing K2S/K2SO3 at temperatures or = 800 C: Pt, Mo, W, quartz, machinable glass, BN, high density graphite, pyrolytic coated graphite, and alumina. Of these, only alumina was observed to be chemically inert to both K2S but reacted with K2SO3. The other materials were not suitable for either substance. Thermodynamic calculations based on measured vapor pressures and approximate free energy functions are described. Results from isothermal total mass loss experiments and from thermogravimetric experiments are also included.

Survey on Teaching Science to K-12 Students with Disabilities: Teacher Preparedness and Attitudes

NASA Astrophysics Data System (ADS)

Kahn, Sami; Lewis, Anna R.

2014-12-01

Students with disabilities are increasingly included in general education science classrooms and are expected to demonstrate academic proficiency on standardized assessments. Teacher preparation and attitudes have been cited as major factors contributing to either the success or failure of students with disabilities in science. In order to assess the current state of what could be facilitative or inhibitory influences, a national online survey to which 1,088 K-12 science teachers responded was conducted. Mixed methods' analyses suggest that science teachers receive little formal training and feel underprepared to teach students with disabilities. Results identify specific gaps in science teachers' education, as well as attitudinal and institutional barriers that may inhibit students with disabilities' success. However, science teachers remain highly receptive to training and collaboration. Implications for science teacher education are discussed.

Implementing a clinical ethics needs assessment survey: results of a pilot study (part 2 of 2).

PubMed

Frolic, Andrea; Andreychuk, Sandra; Seidlitz, Wendy; Djuric-Paulin, Angela; Flaherty, Barb; Jennings, Barb; Peace, Donna

2013-03-01

This paper details the implementation of the Clinical Ethics Needs Assessment Survey (CENAS) through a pilot study in five units within Hamilton Health Sciences. We describe how these pilot sites were selected, how we implemented the survey, the significant results and our interpretation of the findings. The primary goal of this paper is to share our experiences using this tool, specifically the challenges we encountered conducting a staff ethics needs assessment across different units in a large teaching hospital, and the facilitators to our success. We conclude with a discussion of the limitations of this study, our plans for using the results to develop a proactive ethics education strategy, and suggestions for other organizations wishing to adapt the CENAS to assess their staff ethics needs. Our secondary goal is to advance the "quality agenda" for ethics programs by demonstrating how a tool like the CENAS can be used to design more effective educational interventions, and to support strategic planning and proactive priority-setting for ethics programs.

Phase relations in KxFe2-ySe2 and the structure of superconducting KxFe2Se2 via high-resolution synchrotron diffraction

NASA Astrophysics Data System (ADS)

Shoemaker, Daniel P.; Chung, Duck Young; Claus, Helmut; Francisco, Melanie C.; Avci, Sevda; Llobet, Anna; Kanatzidis, Mercouri G.

2012-11-01

Superconductivity in iron selenides has experienced a rapid growth, but not without major inconsistencies in the reported properties. For alkali-intercalated iron selenides, even the structure of the superconducting phase is a subject of debate, in part because the onset of superconductivity is affected much more delicately by stoichiometry and preparation than in cuprate or pnictide superconductors. If high-quality, pure, superconducting intercalated iron selenides are ever to be made, the intertwined physics and chemistry must be explained by systematic studies of how these materials form and by and identifying the many coexisting phases. To that end, we prepared pure K2Fe4Se5 powder and superconductors in the KxFe2-ySe2 system, and examined differences in their structures by high-resolution synchrotron and single-crystal x-ray diffraction. We found four distinct phases: semiconducting K2Fe4Se5, a metallic superconducting phase KxFe2Se2 with x ranging from 0.38 to 0.58, the phase KFe1.6Se2 with full K occupancy and no Fe vacancy ordering, and a oxidized phase K0.51(5)Fe0.70(2)Se that forms the PbClF structure upon exposure to moisture. We find that the vacancy-ordered phase K2Fe4Se5 does not become superconducting by doping, but the distinct iron-rich minority phase KxFe2Se2 precipitates from single crystals upon cooling from above the vacancy ordering temperature. This coexistence of separate metallic and semiconducting phases explains a broad maximum in resistivity around 100 K. Further studies to understand the solubility of excess Fe in the KxFe2-ySe2 structure will shed light on the maximum fraction of superconducting KxFe2Se2 that can be obtained by solid state synthesis.

DES Y1 Results: Validating Cosmological Parameter Estimation Using Simulated Dark Energy Surveys

DOE Office of Scientific and Technical Information (OSTI.GOV)

MacCrann, N.; et al.

We use mock galaxy survey simulations designed to resemble the Dark Energy Survey Year 1 (DES Y1) data to validate and inform cosmological parameter estimation. When similar analysis tools are applied to both simulations and real survey data, they provide powerful validation tests of the DES Y1 cosmological analyses presented in companion papers. We use two suites of galaxy simulations produced using different methods, which therefore provide independent tests of our cosmological parameter inference. The cosmological analysis we aim to validate is presented in DES Collaboration et al. (2017) and uses angular two-point correlation functions of galaxy number counts and weak lensing shear, as well as their cross-correlation, in multiple redshift bins. While our constraints depend on the specific set of simulated realisations available, for both suites of simulations we find that the input cosmology is consistent with the combined constraints from multiple simulated DES Y1 realizations in themore » $$\\Omega_m-\\sigma_8$$ plane. For one of the suites, we are able to show with high confidence that any biases in the inferred $$S_8=\\sigma_8(\\Omega_m/0.3)^{0.5}$$ and $$\\Omega_m$$ are smaller than the DES Y1 $$1-\\sigma$$ uncertainties. For the other suite, for which we have fewer realizations, we are unable to be this conclusive; we infer a roughly 70% probability that systematic biases in the recovered $$\\Omega_m$$ and $$S_8$$ are sub-dominant to the DES Y1 uncertainty. As cosmological analyses of this kind become increasingly more precise, validation of parameter inference using survey simulations will be essential to demonstrate robustness.« less

Assessment Strategies for Implementing Ngss in K12 Earth System Science Classrooms

NASA Astrophysics Data System (ADS)

McAuliffe, C.

2016-12-01

Several science education researchers have led assessment efforts that provide strategies particularly useful for evaluating the threedimensional learning that is central to NGSS (DeBarger, A. H., Penuel, W. R., Harris, C. J., Kennedy, C. K., 2016; Knight, A. M. & McNeill, K. L., 2015; McNeill, K. L., KatshSinger, R. & Pelletier, P., 2015; McNeill K.L., et.al., 2015; McNeill, K.L., & Krajcik, J.S., 2011; Penuel, W., 2016). One of the basic premises of these researchers is that, "Assessment is a practice of argument from evidence based on what students say, do, and write" and that "the classroom is the richest place to gather evidence of what students know (Penuel, W., 2016). The implementation of the NGSS in Earth System Science provides a unique opportunity for geoscience education researchers to study student learning and contribute to the development of this research as well as for geoscience educators to apply these approaches and strategies in their own work with K12 inservice and preservice educators. DeBarger, A. H., Penuel, W. R., Harris, C. J., Kennedy, C. K. (2016). Building an Assessment Argument to Design and Use Next Generation Science Assessments in Efficacy Studies of Curriculum Interventions. American†Journal†of†Evaluation†37(2) 174192Æ Knight, A. M. & McNeill, K. L. (2015). Comparing students' individual written and collaborative oral socioscientific arguments. International Journal of Environmental and Science Education.10(5), 23647. McNeill, K. L., KatshSinger, R. & Pelletier, P. (2015). Assessing science practices-Moving your class along a continuum. Science Scope. McNeill, K.L., & Krajcik, J.S. (2011). Supporting Grade 5-8 Students in Constructing Explanations in Science: The Claim, Evidence, and Reasoning Framework for Talk and Writing. Upper Saddle River, New Jersey: Pearson. Penuel, W. (2016). Classroom Assessment Strategies for NGSS Earth and Space Sciences. Implementing†the†NGSS†Webinar†Series, February 11, 2016.

Two-Dimensional Superconductivity Emerged at Monatomic Bi(2-) Square Net in Layered Y2O2Bi via Oxygen Incorporation.

PubMed

Sei, Ryosuke; Kitani, Suguru; Fukumura, Tomoteru; Kawaji, Hitoshi; Hasegawa, Tetsuya

2016-09-07

Discovery of layered superconductors such as cuprates and iron-based compounds has unveiled new science and compounds. In these superconductors, quasi-two-dimensional layers including transition metal cations play principal role in the superconductivity via carrier doping by means of aliovalent-ion substitution. Here, we report on a two-dimensional superconductivity at 2 K in ThCr2Si2-type layered oxide Y2O2Bi possessing conducting monatomic Bi(2-) square net, possibly associated with an exotic superconductivity. The superconductivity emerges only in excessively oxygen-incorporated Y2O2Bi with expanded inter-net distance, in stark contrast to nonsuperconducting pristine Y2O2Bi reported previously. This result suggests that the element incorporation into hidden interstitial site could be an alternative approach to conventional substitution and intercalation methods for search of novel superconductors.

Reversing the Downward Spiral of Science Instruction in K-2 Classrooms

NASA Astrophysics Data System (ADS)

Sandholtz, Judith Haymore; Ringstaff, Cathy

2011-10-01

This study investigated the extent to which teacher professional development led to changes in science instruction in K-2 classrooms in rural school districts. The research specifically examined changes in (a) teachers' content knowledge in science; (b) teachers' self-efficacy related to teaching science; (c) classroom instructional time allotted to science; and (d) instructional strategies used in science. The study also investigated contextual factors contributing to or hindering changes in science instruction. Data sources included a teacher survey, a self-efficacy assessment, content knowledge tests, interviews, and classroom observations. After one year in the program, teachers showed increased content knowledge and self-efficacy in teaching science; they spent more instructional time on science and began using different instructional strategies. Key contextual factors included curricular demands, resources, administrative support, and support from other teachers.

High rate DC-reactive sputter deposition of Y 2O 3 film on the textured metal substrate for the superconducting coated conductor

NASA Astrophysics Data System (ADS)

Kim, Ho-Sup; Park, Chan; Ko, Rock-Kil; Shi, Dongqui; Chung, Jun-Ki; Ha, Hong-Soo; Park, Yu-Mi; Song, Kyu-Jeong; Youm, Do-Jun

2005-10-01

Y2O3 film was directly deposited on Ni-3at%W substrate by DC reactive sputtering. DC reactive sputtering was carried out using metallic Y target and water vapor for oxidizing the elements of metallic target on the substrate. The detailed conditions of DC reactive sputtering for depositions of Y2O3 films were investigated. The window of water vapor for proper growth of Y2O3 films was determined by sufficient oxidations of the Y2O3 films and the non-oxidation of the target surface, which was required for high rate sputtering. The window turned out to be fairly wide in the chamber used. As the sputtering power was raised, the deposition rate increased without narrowing the window. The fabricated Y2O3 films showed good texture qualities and surface morphologies. The YBCO film deposited directly on the Y2O3 buffered Ni-3at%W substrate showed Tc, Ic (77 K, self field), and Jc (77 K, self field) of 89 K, 64 A/cm and 1.1 MA/cm2, respectively.

Photoluminescence, thermoluminescence glow curve and emission characteristics of Y2O3:Er3+ nanophosphor.

PubMed

N J, Shivaramu; B N, Lakshminarasappa; K R, Nagabhushana; H C, Swart; Fouran, Singh

2018-01-15

Nanocrystalline Er 3+ doped Y 2 O 3 crystals were prepared by a sol gel technique. X-ray diffraction (XRD) patterns showed the cubic structure of Y 2 O 3 and the crystallite size was found to be ~25nm. Optical absorption showed absorption peaks at 454, 495 and 521nm. These peaks are attributed to the 4 F 3/2 + 4 F 5/2 , 4 F 7/2 and 2 H 11/2 + 4 S 3/2 transitions of Er 3+ . Under excitation at 378nm, the appearance of strong green (520-565nm) down conversion emission assigned to the ( 2 H 11/2, 4 S 3/2 )→ 4 I 15/2 transition and the feeble red (650-665nm) emission is assigned to the 4 F 9/2 → 4 I 15/2 transition. The color chromaticity coordinates showed emission in the green region. The strong green emission of Y 2 O 3 :Er 3+ nanophosphor may be useful for applications in solid compact laser devices. Thermoluminescence (TL) studies of γ-irradiated Y 2 O 3 :Er 3+ showed a prominent TL glow peak maximum at 383K along with a less intense shoulder peak at ~425K and a weak glow at 598K. TL emission peaks with maxima at 545, 490, 588 and 622nm for the doped sample were observed at a temperature of 383K and these emissions were due to defect related to the host material. TL kinetic parameters were calculated by a glow curve deconvolution (GCD) method and the obtained results are discussed in detail for their possible usage in high dose dosimetry. Copyright © 2017 Elsevier B.V. All rights reserved.

Cascade production in the reactions γp→K+K+(X) and γp→K+K+π-(X)

NASA Astrophysics Data System (ADS)

Guo, L.; Weygand, D. P.; Battaglieri, M.; Vita, R. De; Kubarovsky, V.; Stoler, P.; Amaryan, M. J.; Ambrozewicz, P.; Anghinolfi, M.; Asryan, G.; Avakian, H.; Bagdasaryan, H.; Baillie, N.; Ball, J. P.; Baltzell, N. A.; Batourine, V.; Battaglieri, M.; Bedlinskiy, I.; Bellis, M.; Benmouna, N.; Berman, B. L.; Biselli, A. S.; Blaszczyk, L.; Bouchigny, S.; Boiarinov, S.; Bradford, R.; Branford, D.; Briscoe, W. J.; Brooks, W. K.; Bültmann, S.; Burkert, V. D.; Butuceanu, C.; Calarco, J. R.; Careccia, S. L.; Carman, D. S.; Chen, S.; Cole, P. L.; Collins, P.; Coltharp, P.; Crabb, D.; Crannell, H.; Crede, V.; Cummings, J. P.; Dashyan, N.; Masi, R. De; Vita, R. De; Sanctis, E. De; Degtyarenko, P. V.; Deur, A.; Dharmawardane, K. V.; Dickson, R.; Djalali, C.; Dodge, G. E.; Donnelly, J.; Doughty, D.; Dugger, M.; Dzyubak, O. P.; Egiyan, H.; Egiyan, K. S.; Fassi, L. El; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Feldman, G.; Funsten, H.; Garçon, M.; Gavalian, G.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Gonenc, A.; Gordon, C. I. O.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guler, N.; Gyurjyan, V.; Hadjidakis, C.; Hafidi, K.; Hakobyan, H.; Hakobyan, R. S.; Hanretty, C.; Hardie, J.; Hersman, F. W.; Hicks, K.; Hleiqawi, I.; Holtrop, M.; Hyde-Wright, C. E.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Ito, M. M.; Jenkins, D.; Johnstone, R.; Jo, H. S.; Joo, K.; Juengst, H. G.; Kalantarians, N.; Kellie, J. D.; Khandaker, M.; Kim, W.; Klein, A.; Klein, F. J.; Klimenko, A. V.; Kossov, M.; Krahn, Z.; Kramer, L. H.; Kuhn, J.; Kuhn, S. E.; Kuleshov, S. V.; Lachniet, J.; Laget, J. M.; Langheinrich, J.; Lawrence, D.; Lee, T.; Li, Ji; Livingston, K.; Lu, H. Y.; MacCormick, M.; Markov, N.; Mattione, P.; McKinnon, B.; Mecking, B. A.; Melone, J. J.; Mestayer, M. D.; Meyer, C. A.; Mibe, T.; Mikhailov, K.; Minehart, R.; Mirazita, M.; Miskimen, R.; Mokeev, V.; Moriya, K.; Morrow, S. A.; Moteabbed, M.; Munevar, E.; Mutchler, G. S.; Nadel-Turonski, P.; Nasseripour, R.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Niczyporuk, B. B.; Niroula, M. R.; Niyazov, R. A.; Nozar, M.; Osipenko, M.; Ostrovidov, A. I.; Park, K.; Pasyuk, E.; Paterson, C.; Pereira, S. Anefalos; Pierce, J.; Pivnyuk, N.; Pocanic, D.; Pogorelko, O.; Pozdniakov, S.; Price, J. W.; Prok, Y.; Protopopescu, D.; Raue, B. A.; Riccardi, G.; Ricco, G.; Ripani, M.; Ritchie, B. G.; Ronchetti, F.; Rosner, G.; Rossi, P.; Sabatié, F.; Salamanca, J.; Salgado, C.; Santoro, J. P.; Sapunenko, V.; Schumacher, R. A.; Serov, V. S.; Sharabian, Y. G.; Sharov, D.; Shvedunov, N. V.; Smith, E. S.; Smith, L. C.; Sober, D. I.; Sokhan, D.; Stavinsky, A.; Stepanyan, S. S.; Stepanyan, S.; Stokes, B. E.; Strakovsky, I. I.; Strauch, S.; Taiuti, M.; Tedeschi, D. J.; Thoma, U.; Tkabladze, A.; Tkachenko, S.; Todor, L.; Tur, C.; Ungaro, M.; Vineyard, M. F.; Vlassov, A. V.; Watts, D. P.; Weinstein, L. B.; Williams, M.; Wolin, E.; Wood, M. H.; Yegneswaran, A.; Zana, L.; Zhang, J.; Zhao, B.; Zhao, Z. W.

2007-08-01

Photoproduction of the cascade resonances has been investigated in the reactions γp→K+K+(X) and γp→K+K+π-(X). The mass splitting of the ground state (Ξ-,Ξ0) doublet is measured to be 5.4±1.8 MeV/c2, consistent with existing measurements. The differential (total) cross sections for the Ξ- have been determined for photon beam energies from 2.75 to 3.85 (4.75) GeV and are consistent with a production mechanism of Y*→K+Ξ- through a t-channel process. The reaction γp→K+K+π-[Ξ0] has also been investigated to search of excited cascade resonances. No significant signal of excited cascade states other than the Ξ-(1530) is observed. The cross-section results of the Ξ-(1530) have also been obtained for photon beam energies from 3.35 to 4.75 GeV.

Semen says: assessing the accuracy of adolescents' self-reported sexual abstinence using a semen Y-chromosome biomarker.

PubMed

Rosenbaum, Janet E; Zenilman, Jonathan M; Rose, Eve; Wingood, Gina M; DiClemente, Ralph J

2017-03-01

Researchers often assess condom use only among participants who report recent sexual behaviour, excluding participants who report no recent vaginal sex or who did not answer questions about their sexual behaviour, but self-reported sexual behaviour may be inaccurate. This study uses a semen Y-chromosome biomarker to assess semen exposure among participants who reported sexual abstinence or did not report their sexual behaviour. This prospective cohort study uses data from 715 sexually active African-American female adolescents in Atlanta, surveyed at baseline, 6 months and 12 months. Participants completed a 40 min interview and were tested for semen Y-chromosome with PCR from a self-administered vaginal swab. We predicted Y-chromosome test results from self-reported sexual behaviour using within-subject panel regression. Among the participants who reported abstinence from vaginal sex in the past 14 days, 9.4% tested positive for semen Y-chromosome. Among item non-respondents, 6.3% tested positive for semen Y-chromosome. Women who reported abstinence and engaged in item non-response regarding their sexual behaviour had respectively 62% and 78% lower odds of testing positive for Y-chromosome (OR 0.38 (0.21 to 0.67), OR 0.22 (0.12 to 0.40)), controlling for smoking, survey wave and non-coital sexual behaviours reported during abstinence. Adolescents who report sexual abstinence under-report semen exposure. Research should validate self-reported sexual behaviour with biomarkers. Adolescents who engage in item non-response regarding vaginal sex test positive for semen Y-chromosome at similar rates, which supports the practice of grouping non-respondents with adolescents reporting abstinence in statistical analysis. NCT00633906. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Thermoelectric properties of p-type Ag{sub 1−x}(Pb{sub 1−y}Sn{sub y}){sub m}Sb{sub 1−z}Te{sub m+2}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahn, Kyunghan; Center for Nanoparticle Research, Institute for Basic Science,; Kong, Huijun

The thermoelectric properties of Ag{sub 1−x}(Pb{sub 1−y}Sn{sub y}){sub m}Sb{sub 1−z}Te{sub m+2} (4≤m≤16, −0.1≤x≤0.3, 1/3≤y≤2/3, 0.2≤z≤0.4; Lead Antimony Silver Tellurium Tin, LASTT-m) compositions were investigated in the temperature range of 300 to ~670 K. All samples crystallize in the average NaCl-type structure without any noticeable second phase and exhibit very narrow bandgaps of <0.1 eV. We studied a range of m values, silver concentrations (x), Pb/Sn ratios (y), and antimony concentrations (z) to determine their effects on the thermoelectric properties. The samples were investigated as melt grown polycrystalline ingots. Varying the Ag contents, the Pb/Sn ratios, and the Sb contents off-stoichiometrymore » allowed us to control the electrical conductivity, the Seebeck coefficient, and the thermal conductivity. The electrical conductivity tends to decrease with decreasing m values. The highest ZT of ~1.1 was achieved at ~660 K for Ag{sub 0.9}Pb{sub 5}Sn{sub 5}Sb{sub 0.8}Te{sub 12} mainly due to the very low lattice thermal conductivity of ~0.4 W/(m K) around 660 K. Also, samples with charge-balanced stoichiometries, Ag(Pb{sub 1−y}Sn{sub y}){sub m}SbTe{sub m+2}, were studied and found to exhibit a lower power factor and higher lattice thermal conductivity than the Ag{sub 1−x}(Pb{sub 1−y}Sn{sub y}){sub m}Sb{sub 1−z}Te{sub m+2} compositions. - Graphical abstract: The Ag{sub 1−x}(Pb{sub 1−y}Sn{sub y}){sub m}Sb{sub 1−z}Te{sub m+2} system defines a complex and flexible class of tunable thermoelectric class of materials with high performance.« less

Mutation of A677 in histone methyltransferase EZH2 in human B-cell lymphoma promotes hypertrimethylation of histone H3 on lysine 27 (H3K27)

PubMed Central

McCabe, Michael T.; Graves, Alan P.; Ganji, Gopinath; Diaz, Elsie; Halsey, Wendy S.; Jiang, Yong; Smitheman, Kimberly N.; Ott, Heidi M.; Pappalardi, Melissa B.; Allen, Kimberly E.; Chen, Stephanie B.; Della Pietra, Anthony; Dul, Edward; Hughes, Ashley M.; Gilbert, Seth A.; Thrall, Sara H.; Tummino, Peter J.; Kruger, Ryan G.; Brandt, Martin; Schwartz, Benjamin; Creasy, Caretha L.

2012-01-01

Trimethylation of histone H3 on lysine 27 (H3K27me3) is a repressive posttranslational modification mediated by the histone methyltransferase EZH2. EZH2 is a component of the polycomb repressive complex 2 and is overexpressed in many cancers. In B-cell lymphomas, its substrate preference is frequently altered through somatic mutation of the EZH2 Y641 residue. Herein, we identify mutation of EZH2 A677 to a glycine (A677G) among lymphoma cell lines and primary tumor specimens. Similar to Y641 mutant cell lines, an A677G mutant cell line revealed aberrantly elevated H3K27me3 and decreased monomethylated H3K27 (H3K27me1) and dimethylated H3K27 (H3K27me2). A677G EZH2 possessed catalytic activity with a substrate specificity that was distinct from those of both WT EZH2 and Y641 mutants. Whereas WT EZH2 displayed a preference for substrates with less methylation [unmethylated H3K27 (H3K27me0):me1:me2 kcat/Km ratio = 9:6:1] and Y641 mutants preferred substrates with greater methylation (H3K27me0:me1:me2 kcat/Km ratio = 1:2:13), the A677G EZH2 demonstrated nearly equal efficiency for all three substrates (H3K27me0:me1:me2 kcat/Km ratio = 1.1:0.6:1). When transiently expressed in cells, A677G EZH2, but not WT EZH2, increased global H3K27me3 and decreased H3K27me2. Structural modeling of WT and mutant EZH2 suggested that the A677G mutation acquires the ability to methylate H3K27me2 through enlargement of the lysine tunnel while preserving activity with H3K27me0/me1 substrates through retention of the Y641 residue that is crucial for orientation of these smaller substrates. This mutation highlights the interplay between Y641 and A677 residues in the substrate specificity of EZH2 and identifies another lymphoma patient population that harbors an activating mutation of EZH2. PMID:22323599

Designing K-2 Formative Assessment Tasks

ERIC Educational Resources Information Center

Reed, Kristen E.; Goldenberg, E. Paul

2016-01-01

Formative assessment is a process used by teachers and students during instruction that provides feedback to adjust ongoing teaching and learning to improve students' achievements of intended instructional outcomes. Formative assessment means assessment embedded in instruction. That definition was adopted in 2006 by the Council of Chief State…

The K-Band Quasar Luminosity Function from an SDSS and UKIDSS Matched Catalog

NASA Astrophysics Data System (ADS)

Peth, Michael; Ross, N. P.; Schneider, D. P.

2010-01-01

We match the 1,015,082 quasars from the Sloan Digital Sky Survey (SDSS) DR6 Photometric Quasar catalog to the UKIRT Infrared Digital Sky Survey (UKIDSS) Large Area Survey (LAS) DR3 to produce a catalog of 130,827 objects with optical (ugriz) and infrared (YJHK) measurements over an area of 1,200 sq. deg. A matching radius of 1'’ is used; the positional standard deviations of SDSS DR6 quasars and UKIDSS LAS is δRA = 0.137'’ and δDec = 0.131''. The catalog contains 74,351 K-band detections and 42,133 objects have coverage in all four NIR bands. In addition to the catalog, we present optical and NIR color-redshift and color-color plots. The photometric vs. spectroscopic redshift plots demonstrate how unreliable high reported photometric redshifts can be. This forces us to focus on z4.6 quasars are compared to our highest redshift objects. The giK color-color plot demonstrates that stellar contamination only affects a small sample of the objects. Distributions for Y,J,H,K and i-bands reveal insights into the flux limits in each magnitude. We investigate the distribution of redshifts from different data sets and investigate the legitimacy of certain measured photometric redshift regions. For in-depth analysis, we focus on the 300 sq. deg area equatorial SDSS region designated as Stripe 82. We measure the observed K-band quasar luminosity function (QLF) for a subset of 9,872, z<2.2 objects. We find the shape of the K-band QLF is very similar to that of the optical QLF, over the considered redshift ranges. Our calculated K-Band QLFs broadly match previous optical QLFs calculated from the SDSS and 2SLAQ QSO surveys and should provide important constraints linking unobscured optical quasars to Mid-Infrared detected, dusty and obscured AGNs at high-redshift.

Study of Bc→ψ (2 S )K , ηc(2 S )K , ψ (3770 )K decays with perturbative QCD approach

NASA Astrophysics Data System (ADS)

Duan, Feng-Bo; Yu, Xian-Qiao

2018-05-01

We study the Bc→ψ (2 S ) K , ηc(2 S ) K , ψ (3770 ) K decays with perturbative QCD approach based on kT factorization. The new orbitally excited charmonium distribution amplitudes ψ (1 3D1) based on the Schrödinger wave function of the n =1 , l =2 state for the harmonic-oscillator potential are employed. By using the corresponding distribution amplitudes, we calculate the branching ratio of Bc→ψ (2 S ) K , ηc(2 S ) K , ψ (3770 ) K decays and the form factors A0 ,1 ,2 and V for the transition Bc→ψ (1 3D1) . We obtain the branching ratio of both Bc→ψ (2 S ) K and Bc→ηc(2 S ) K are at the order of 10-5. The effects of two sets of the S-D mixing angle θ =-1 2 ° and θ =2 7 ° for the decay Bc→ψ (3770 ) K are studied first in this paper. Our calculations show that the branching ratio of the decay Bc→ψ (3770 ) K can be raised from the order of 10-6 to the order of 10-5 at the mixing angle θ =-1 2 ° , which can be tested by the running LHC-b experiments.

The Keck/OSIRIS Nearby AGN Survey (KONA). I. The Nuclear K-band Properties of Nearby AGN

NASA Astrophysics Data System (ADS)

Müller-Sánchez, F.; Hicks, E. K. S.; Malkan, M.; Davies, R.; Yu, P. C.; Shaver, S.; Davis, B.

2018-05-01

We introduce the Keck OSIRIS Nearby AGN survey (KONA), a new adaptive optics-assisted integral-field spectroscopic survey of Seyfert galaxies. KONA permits at ∼0.″1 resolution a detailed study of the nuclear kinematic structure of gas and stars in a representative sample of 40 local bona fide active galactic nucleus (AGN). KONA seeks to characterize the physical processes responsible for the coevolution of supermassive black holes and galaxies, principally inflows and outflows. With these IFU data of the nuclear regions of 40 Seyfert galaxies, the KONA survey will be able to study, for the first time, a number of key topics with meaningful statistics. In this paper we study the nuclear K-band properties of nearby AGN. We find that the K-band (2.1 μm) luminosities of the compact Seyfert 1 nuclei are correlated with the hard X-ray luminosities, implying a non-stellar origin for the majority of the continuum emission. The best-fit correlation is log L K = 0.9log L 2–10 keV + 4 over three orders of magnitude in both K-band and X-ray luminosities. We find no strong correlation between 2.1 μm luminosity and hard X-ray luminosity for the Seyfert 2 galaxies. The spatial extent and spectral slope of the Seyfert 2 galaxies indicate the presence of nuclear star formation and attenuating material (gas and dust), which in some cases is compact and in some galaxies extended. We detect coronal-line emission in 36 galaxies and for the first time in 5 galaxies. Finally, we find 4/20 galaxies that are usually classified as Seyfert 2 based on their optical spectra exhibit a broad component of Brγ emission, and one galaxy (NGC 7465) shows evidence of a double nucleus. Based on observations at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The observatory was made possible by the generous financial support of the W. M

Pressure dependence of thermal physical properties of A-type R2O3 (R=Y, La): A first-principles study

NASA Astrophysics Data System (ADS)

Li, Y. F.; Xiao, B.; Sun, L.; Gao, Y. M.; Ma, S. Q.; Yi, D. W.

2017-04-01

The mechanical, electronic and thermal physical properties of A-type R2O3 (R=Y, La) under hydrostatic pressure are studied by first-principles calculations. The calculated band gap is 6.3 eV (5.9 eV) for Y2O3 (La2O3). Under hydrostatic pressure, both phases show anisotropic elasticity in different crystallographic directions. The isothermal bulk modulus of R2O3 decreases monotonically with the increasing of temperature from 300 K to 1500 K. The intrinsic ductile nature of both phases is confirmed by the obtained B/G ratio. The temperature dependence of linear TECs of La2O3 is stronger than that of Y2O3, and the linear TECs in [001] direction show larger values in both phases than those in [010] direction. At room temperature, the average linear TECs for Y2O3 and La2O3 are 8.40×10-6 K-1 and 8.42×10-6 K-1, respectively. Other thermal physical properties such as specific heats (CV, and CP), entropy (S), sound velocity and Debye temperature are also obtained.

RVxK2: Simultaneous PRV Program with Kepler/K2 Campaign 16

NASA Astrophysics Data System (ADS)

Xuesong Wang, Sharon; RVxK2 team

2018-01-01

Introducing the RVxK2 program: simultaneous precise radial velocity (PRV) observations with Kepler/K2 Campaign 16, from Dec 7 2017 through Feb 26 2018 (website: rvxk2.com). K2 will provide short cadence photometric data on five carefully selected stars, including the brightest M dwarf in C16 field, a solar analog, and three bright G/K subgiants. K2 will also provide long cadence data on the next three brightest K or M dwarfs in the C16 field. Our campaign includes several precise RV instruments around the globe, including Keck/HIRES, APF, IRTF/iSHELL, SONG, MINERVA, PARAS, representing the first organized, extensive, simultaneous RV campaign with space photometry. Our primary science goal is to characterize and understand stellar jitter and stellar activity. This RV+K2 campaign will provide the community with an unprecedented dataset of RV spectra and precise photometry to study stellar jitter on a broad range of time scales, from minutes to 80 days. We will gather the first ever RV+photometry dataset aiming at characterizing stellar granulation, the most poorly understood term among all astrophysical sources of stellar jitter. This project will also enable the first asteroseismic studies with simultaneous precise RVs and photometry, while searching for planets in the brightest nearby G to M dwarfs in the field.

Influence of Y2O3 Addition on Crystallization, Thermal, Mechanical, and Electrical Properties of BaO-Al2O3-B2O3-SiO2 Glass-Ceramic for Ceramic Ball Grid Array Package

NASA Astrophysics Data System (ADS)

Li, Bo; Li, Wei; Zheng, Jingguo

2018-01-01

Y2O3 addition has a significant influence on the crystallization, thermal, mechanical, and electrical properties of BaO -Al2O3 -B2O3 -SiO2 (BABS) glass-ceramics. Semi-quantitative calculation based on x-ray diffraction demonstrated that with increasing Y2O3 content, both the crystallinity and the phase content of cristobalite gradually decreased. It is effective for the additive Y2O3 to inhibit the formation of cristobalite phase with a large coefficient of thermal expansion value. The flexural strength and the Young's modulus, thus, are remarkably increased from 140 MPa to 200 MPa and 56.5 GPa to 63.7 GPa, respectively. Also, the sintering kinetics of BABS glass-ceramics with various Y2O3 were investigated using the isothermal sintering shrinkage curve at different sintering temperatures. The sintering activation energy Q sharply decreased from 99.8 kJ/mol to 81.5 kJ/mol when 0.2% Y2O3 was added, which indicated that a small amount of Y2O3 could effectively promote the sintering procedure of BABS glass-ceramics.

Large magnetoresistance in (La1-xCaxMnO3)1-y:ZrO2 composite

NASA Astrophysics Data System (ADS)

Das, D.; Saha, A.; Russek, S. E.; Raj, R.; Bahadur, D.

2003-05-01

Colossal magnetoresistance (CMR) composite materials have been synthesized to explore the possibility of improving magneto-transport and structural properties in CMR systems. In this work we describe (La1-xCaxMnO3)1-y (LCMO) (ZrO2)y (x≈0.3 and 0.0⩽y⩽0.40 mole %) composites that have been synthesized using a modified (non Pechini type) sol-gel technique. Magnetoresistivity of the composites was evaluated at 5 T field and in the temperature range 5-300 K. The composites show higher magnitude of MR compared to pure LCMO. The MR rises from a base value 76%, for the case y=0, to a maximum value of 93.8%, obtained at y=0.05. dc susceptibility measurements show a distinct ferromagnetic to paramagnetic transition in all composites. The ferromagnetic transition temperature (TC) drops from 225 K in pure LCMO (y=0) to 121 K in y=0.05 and then slowly rises to 157 K as y increases. The plots of zero field cooled susceptibility χZFC (T) and field cooled susceptibility χFC (T) diverge clearly below TC, indicating magnetic irreversibility. The composite exhibits a clear metal-insulator transition (TMI) at or just above the magnetic transition. The peak resistivity ρMI at the metal-insulator transition also exhibits interesting changes. For pure LCMO polycrystals, ρMI=102 Ω cm, but it increases to 228 Ω cm for y=0.05 and then gradually decreases to 1.94 Ω cm for y⩾0.10. The phase evolution in the LCMO:ZrO2 composites was studied by x-ray powder diffraction and correlated to the magnetic and electrical properties.

Appearance of superconductivity at the vacancy order-disorder boundary in KxFe2 -ySe2

NASA Astrophysics Data System (ADS)

Duan, Chunruo; Yang, Junjie; Ren, Yang; Thomas, Sean M.; Louca, Despina

2018-05-01

The role of phase separation and the effect of Fe-vacancy ordering in the emergence of superconductivity in alkali metal doped iron selenides AxFe2 -ySe2 (A = K, Rb, Cs) is explored. High energy x-ray diffraction and Monte Carlo simulation were used to investigate the crystal structure of quenched superconducting (SC) and as-grown nonsuperconducting (NSC) KxFe2 -ySe2 single crystals. The coexistence of superlattice structures with the in-plane √{2 }×√{2 } K-vacancy ordering and the √{5 }×√{5 } Fe-vacancy ordering were observed in both the SC and NSC crystals alongside the I4/mmm Fe-vacancy-free phase. Moreover, in the SC crystals, an Fe-vacancy-disordered phase is additionally proposed to be present. Monte Carlo simulations suggest that it appears at the boundary between the I4/mmm vacancy-free phase and the I4/m vacancy-ordered phases (√{5 }×√{5 } ). The vacancy-disordered phase is nonmagnetic and is most likely the host of superconductivity.

What Do K-12 Teachers Think about Including Student Surveys in Their Performance Ratings?

ERIC Educational Resources Information Center

Dretzke, Beverly J.; Sheldon, Timothy D.; Lim, Alicia

2015-01-01

This study investigated K-12 teachers' opinions about the use of student surveys as a component of a teacher evaluation system. Surveys were administered to teachers at the beginning of the school year and again in the spring. Analyses of teachers' responses on the fall survey indicated tentative support for the inclusion of student feedback in…

M2K Planet Search: Spectroscopic Screening and Transit Photometry

NASA Astrophysics Data System (ADS)

Mann, Andrew; Gaidos, E.; Fischer, D.; Lepine, S.

2010-10-01

The M2K project is a search for planets orbiting nearby early M and late K dwarf drawn from the SUPERBLINK catalog. M and K dwarfs are highly attractive targets for finding low-mass and habitable planets because (1) close-in planets are more likely to orbit within their habitable zone, (2) planets orbiting them induce a larger Doppler signal and have deeper transits than similar planets around F, G, and early K type stars, (3) planet formation models predict they hold an abundance of super-Earth sized planets, and (4) they represent the vast majority of the stars close enough for direct imaging techniques. In spite of this, only 10% of late K and early M dwarfs are being monitored by current Doppler surveys. As part of the M2K project we have obtained low-resolution spectra for more than 2000 of our sample of 10,000 M and K dwarfs. We vet our sample by screening these stars for high metallicity and low chromospheric activity. We search for transits on targets showing high RMS Doppler signal and photometry candidates provided by SuperWASP project. By using "snapshot” photometry have been able to achieve sub-millimag photometry on numerous transit targets in the same night. With further follow-up observations we will be able to detect planets smaller than 10 Earth masses.

Critical phenomena on k -booklets

NASA Astrophysics Data System (ADS)

Grassberger, Peter

2017-01-01

We define a "k -booklet" to be a set of k semi-infinite planes with -∞ y ≥0 , glued together at the edges (the "spine") y =0 . On such booklets we study three critical phenomena: self-avoiding random walks, the Ising model, and percolation. For k =2 , a booklet is equivalent to a single infinite lattice, and for k =1 to a semi-infinite lattice. In both these cases the systems show standard critical phenomena. This is not so for k ≥3 . Self-avoiding walks starting at y =0 show a first-order transition at a shifted critical point, with no power-behaved scaling laws. The Ising model and percolation show hybrid transitions, i.e., the scaling laws of the standard models coexist with discontinuities of the order parameter at y ≈0 , and the critical points are not shifted. In the case of the Ising model, ergodicity is already broken at T =Tc , and not only for T y .

Suppressor Analysis Reveals a Role for SecY in the SecA2-Dependent Protein Export Pathway of Mycobacteria

PubMed Central

Ligon, Lauren S.; Rigel, Nathan W.; Romanchuk, Artur; Jones, Corbin D.

2013-01-01

All bacteria use the conserved Sec pathway to transport proteins across the cytoplasmic membrane, with the SecA ATPase playing a central role in the process. Mycobacteria are part of a small group of bacteria that have two SecA proteins: the canonical SecA (SecA1) and a second, specialized SecA (SecA2). The SecA2-dependent pathway exports a small subset of proteins and is required for Mycobacterium tuberculosis virulence. The mechanism by which SecA2 drives export of proteins across the cytoplasmic membrane remains poorly understood. Here we performed suppressor analysis on a dominant negative secA2 mutant (secA2 K129R) of the model mycobacterium Mycobacterium smegmatis to better understand the pathway used by SecA2 to export proteins. Two extragenic suppressor mutations were identified as mapping to the promoter region of secY, which encodes the central component of the canonical Sec export channel. These suppressor mutations increased secY expression, and this effect was sufficient to alleviate the secA2 K129R phenotype. We also discovered that the level of SecY protein was greatly diminished in the secA2 K129R mutant, but at least partially restored in the suppressors. Furthermore, the level of SecY in a suppressor strongly correlated with the degree of suppression. Our findings reveal a detrimental effect of SecA2 K129R on SecY, arguing for an integrated system in which SecA2 works with SecY and the canonical Sec translocase to export proteins. PMID:23913320

Synthesis and electrical properties of (Pb,Co)Sr2(Y,Ca)Cu2Oz

NASA Astrophysics Data System (ADS)

Tashiro, T.; Maeda, T.; Abe, R.; Takechi, S.; Takahashi, T.; Haruta, M.; Horii, S.

One of related materials to high-temperature superconductors (HTSC's) with nominal compositions of (Pb0.5Co0.5)Sr2(Y1xCax)Cu2Oz (x=0∼0.6) is synthesized and characterized. All samples are nearly single-phase, and its crystal structure is likely to be so-called "1-2-1-2" type which is one of typical structures of HTSC's. Electrical resistivity is decreased as x increases. While superconductivity is not observed at temperatures between room-temperature and 20 K for all samples, temperature dependence of the resistivity exhibits metallic behavior down to 150 K for x=0.5. Phase formation and transport behavior are discussed focusing on mixed valence-state of Co2+ and Co3+.

Feasibility of using a tablet computer survey for parental assessment of resident communication skills.

PubMed

Co, John Patrick T; Mohamed, Hodon; Kelleher, Mary Louise; Edgman-Levitan, Susan; Perrin, James M

2008-01-01

The Accreditation Council for Graduate Medical Education recommends using patient surveys for assessing resident competency in interpersonal and communication skills. Despite the existence of several validated patient surveys for communication assessment, no system has been developed for their sustained use in resident assessment. We developed and pilot tested a system to collect surveys from parents of hospitalized children on the day of discharge. We used a 28-item, tablet computer-based survey that measures individual provider and team communication. The computer displays resident photographs to ensure accurate identification and offers the survey in multiple languages. We assessed parental acceptance of the system by analyzing response rate, as well as reasons for response and nonresponse. Of the 98 eligible parents that were approached, 62 (63%) completed the survey. Only 2 (2%) of the eligible families refused to participate, and only 5 (5%) refused participation because of the survey not being available in a language they were familiar with. Use of a tablet computer parent survey for resident assessment is feasible, with response rates comparable to those of mailed surveys. The low rate of parental refusal indicates our system could be used to attain sufficient numbers of survey responses to help validly measure resident communication skills.

Evidence for filamentary superconductivity up to 220 K in oriented multiphase Y-Ba-Cu-O thin films

NASA Astrophysics Data System (ADS)

Schönberger, R.; Otto, H. H.; Brunner, B.; Renk, K. F.

1991-02-01

We report on the observation of filamentary superconductivity up to 220 K in multiphase Y-Ba-Cu-O materials that are deposited as highly oriented thin films on (110)-SrTiO 3 substrates by laser ablation from ceramic targets. The high temperature zero resistivity states are reproducible after temperature cycling down to 80 K for samples treated by a special oxygenation and ozonization process at 340 K and measured in a pure oxygen atmosphere. Our results on thin films confirm former experiments of J.T. Chen and co-workers obtained on ceramic samples with preferred crystallite orientation. A close connection between superconductivity and structural instabilities of most likely ferroic nature, which are observed more often for YBa 2Cu 3O 7 in a narrow temperature range near 220 K, is suggested.

A 1500 deg2 near infrared proper motion catalogue from the UKIDSS Large Area Survey

NASA Astrophysics Data System (ADS)

Smith, Leigh; Lucas, P. W.; Burningham, B.; Jones, H. R. A.; Smart, R. L.; Andrei, A. H.; Catalán, S.; Pinfield, D. J.

2014-02-01

The United Kingdom Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS) began in 2005, with the start of the UKIDSS programme as a 7 year effort to survey roughly 4000 deg2 at high Galactic latitudes in Y, J, H and K bands. The survey also included a significant quantity of two epoch J band observations, with an epoch baseline greater than 2 years to calculate proper motions. We present a near-infrared proper motion catalogue for the 1500 deg2 of the two epoch LAS data, which includes 135 625 stellar sources and a further 88 324 with ambiguous morphological classifications, all with motions detected above the 5σ level. We developed a custom proper motion pipeline which we describe here. Our catalogue agrees well with the proper motion data supplied for a 300 deg2 subset in the current Wide Field Camera Science Archive (WSA) 10th data release (DR10) catalogue, and in various optical catalogues, but it benefits from a larger matching radius and hence a larger upper proper motion detection limit. We provide absolute proper motions, using LAS galaxies for the relative to absolute correction. By using local second-order polynomial transformations, as opposed to linear transformations in the WSA, we correct better for any local distortions in the focal plane, not including the radial distortion that is removed by the UKIDSS pipeline. We present the results of proper motion searches for new brown dwarfs and white dwarfs. We discuss 41 sources in the WSA DR10 overlap with our catalogue with proper motions >300 mas yr-1, several of which are new detections. We present 15 new candidate ultracool dwarf binary systems.

Adenosine triphosphate induces P2Y2 activation and interleukin-8 release in human esophageal epithelial cells.

PubMed

Wu, Liping; Oshima, Tadayuki; Fukui, Hirokazu; Watari, Jiro; Miwa, Hiroto

2017-07-01

Immune-mediated mucosal inflammation characterized by the release of interleukin (IL)-8 is associated with gastroesophageal reflux disease. ATP released by human esophageal epithelial cells (HEECs) mediates the release of cytokines through P2 nucleotide receptors that are present on various cells, including HEECs. This study characterized and identified human esophageal epithelial P2 receptors that are responsible for ATP-mediated release of IL-8 by using a human esophageal stratified squamous epithelial model. Primary HEECs were cultured with the use of an air-liquid interface (ALI) system. The ATP analogue adenosine 5'-O-3-thiotriphosphate (ATP-γ-S) was added to the basolateral compartment, and IL-8 release was measured. Involvement of the P2Y2 receptor was assessed with the use of selective and non-selective receptor antagonists and a P2Y2 receptor agonist. Expression of the P2Y2 receptor was assessed using western blotting and immunohistochemistry. Adenosine triphosphate-γ-S induced IL-8 release through the P2Y2 receptor. A P2Y2 receptor antagonist but not a P2X3 receptor antagonist or a P2Y1 receptor antagonist blocked ATP-γ-S-mediated IL-8 release. Conversely, a P2Y2 receptor agonist induced IL-8 release. Western blotting and immunohistochemistry of the P2Y2 receptor showed strong expression of the P2Y2 receptor on ALI-cultured HEECs and in human esophagus. Inhibition of extracellular signal-regulated kinase but not of protein kinase C blocked the ATP-mediated release of IL-8. ATP-γ-S induced phosphorylation of extracellular signal-regulated kinase, and a P2Y2 receptor antagonist blocked this phosphorylation. Interleukin-8 release after purinergic stimulation in ALI-cultured HEECs is mediated through P2Y2 receptor activation. ATP-induced IL-8 release maybe involved in the pathogenesis of refractory gastroesophageal reflux disease. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

The system K2Mg2(SO4)3 (langbeinite)-K2Ca2(SO4)3 (calcium-langbeinite)

USGS Publications Warehouse

Morey, G.W.; Rowe, J.J.; Fournier, R.O.

1964-01-01

The join between the compositions K2Mg2(SO4)3 and K2Ca2(SO4)3 was studied by means of high-temperature equilibrium quenching techniques and by means of a heating stage mounted on an X-ray diffractometer. Complete solid solution exists in the system, but at 25??C members of the solid solution series are isometric only in the composition range 0-73??5 wt. per cent K2Ca2(SO4)3. At compositions richer in K2Ca2(SO4)3 than 73??5 wt. per cent, members of the series are optically biaxial. At higher temperatures members of the solid solution series are isometric at successively more calcium-rich compositions and pure K2Ca2(SO4)3 is isometric above about 200 ?? 2??C. The system is not binary, as mixtures richer in K2Ca2(SO4)3 than 42 wt. per cent decompose with the formation of liquid and CaSO4. ?? 1964.

The Pan-STARRS1 Small Area Survey 2

NASA Astrophysics Data System (ADS)

Metcalfe, N.; Farrow, D. J.; Cole, S.; Draper, P. W.; Norberg, P.; Burgett, W. S.; Chambers, K. C.; Denneau, L.; Flewelling, H.; Kaiser, N.; Kudritzki, R.; Magnier, E. A.; Morgan, J. S.; Price, P. A.; Sweeney, W.; Tonry, J. L.; Wainscoat, R. J.; Waters, C.

2013-11-01

The Panoramic Survey Telescope and Rapid Response System 1 (Pan-STARRS1) survey is acquiring multi-epoch imaging in five bands (gP1, rP1, iP1, zP1, yP1) over the entire sky north of declination -30° (the 3π survey). In 2011 July a test area of about 70 deg2 was observed to the expected final depth of the main survey. In this, the first of a series of papers targeting the galaxy count and clustering properties of the combined multi-epoch test area data, we present a detailed investigation into the depth of the survey and the reliability of the Pan-STARRS1 analysis software. We show that the Pan-STARRS1 reduction software can recover the properties of fake sources, and show good agreement between the magnitudes measured by Pan-STARRS1 and those from Sloan Digital Sky Survey. We also examine the number of false detections apparent in the Pan-STARRS1 data. Our comparisons show that the test area survey is somewhat deeper than the Sloan Digital Sky Survey in all bands, and, in particular, the z band approaches the depth of the stacked Sloan Stripe 82 data.

Vitamin K2 alleviates type 2 diabetes in rats by induction of osteocalcin gene expression.

PubMed

Hussein, Atef G; Mohamed, Randa H; Shalaby, Sally M; Abd El Motteleb, Dalia M

2018-03-01

The biological mechanisms behind the association between vitamin K (Vit K) and glucose metabolism are uncertain. We aimed to analyze the expression of insulin 1 (Ins 1), insulin 2 (Ins 2) and cyclin D2, the expression of adiponectin and UCP-1 . In addition, we aimed to estimate the doses of Vit K2 able to affect various aspects of glucose and energy metabolism in type 2 diabetes. Thirty adult male rats were allocated equally into five groups: control group, diabetes mellitus group, and groups 3, 4, and 5, which received Vit K 2 at three daily dose levels (10, 15, and 30 mg/kg, respectively) for 8 wk. At the end of the study, blood samples were collected to quantify total osteocalcin, fasting plasma glucose, fasting insulin, and relevant variables. The expression of OC, Ins 1, Ins 2, cyclin D2, adiponectin, UCP-1 genes was analyzed by real-time polymerase chain reaction. After administration of Vit K 2 , a dose-dependent decrease in fasting plasma glucose, hemoglobin A1c and homeostatic model assessment method insulin resistance, and a dose-dependent increase in fasting insulin and homeostatic model assessment method β cell function levels, when compared with diabetes mellitus rats, were detected. There was significant upregulation of OC, Ins 1, Ins 2, or cyclin D2 gene expression in the three treated groups in a dose-dependent manner when compared with the diabetic rats. However, expression of adiponectin and UCP-1 were significantly increased at the highest dose (30 mg/kg daily) only. Vit K 2 administration could improve glycemic status in type 2 diabetic rats by induction of OC gene expression. Osteocalcin could increase β-cell proliferation, energy expenditure, and adiponectin expression. Different concentrations of Vit K 2 were required to affect glucose metabolism and insulin sensitivity. Copyright © 2017 Elsevier Inc. All rights reserved.

Y2K’s Impact on the U.S. Air Force

DTIC Science & Technology

1999-03-01

AU/ACSC/169/1999-03 AIR COMMAND AND STAFF COLLEGE AIR UNIVERSITY Y2K’S IMPACT ON THE U.S. AIR FORCE by William M. Propst, Major, USAF A Research...doom and gloom for the world come 1 January 2000 and I wanted to determine if the predictions were accurate or simply the rantings of a group of...boys Glenn and Jonathan who kept me focused during this year and provided me something to look forward to when all of this over—going back to a loving

Enhancing Parent Involvement in NC-CCSS for K-2 Mathematics

NASA Astrophysics Data System (ADS)

Johnson, D.

2014-12-01

Key Terms:Parent Involvement, Common Core State Standards, Homework, K - 2 Mathematics In this study, the 2014 REU math team developed and provided a workshop that assisted parents in understanding the North Carolina Common Core State Standards for K-2 Mathematics to assist with student homework assignments. Parent involvement is defined as parent participating in the educational processes and experiences of their children. A chi-square analysis was used to analyze data collected from the pre survey and the post survey administered to participants in the workshop. The study revealed all of the individual components of parent involvement were positively and significantly related to educational goals. The study identified various aspects of parent involvement that yielded statistically significant results in affirming that parent involvement attributed to urban student achievement. These findings were particularly helpful for indicating which kinds of parent involvement influenced academic success. Most notably, parent expectations and styles demonstrated a strong relationship with scholastic outcomes. Parent expectations and styles created an educationally oriented ambience that established an understanding of the certain level of support the child needed to succeed academically. The REU mathematics team focused on three essential questions in this study: (1) What practices will increase parent awareness of K-2 NC-CCSS for mathematics at P. W. Moore Elementary School? (2) What methods can be used to strengthen parent skills in assisting with mathematics homework assignments at P. W. Moore Elementary School? (3) What actions can be taken to motivate parent involvement in the school improvement process focusing on mathematics at P. W. Moore Elementary School?

XAFS Study on Chlorination of Y2O3 in LiCl-KCl-ZrCl4 Melt

NASA Astrophysics Data System (ADS)

Okamoto, Yoshihiro; Yaita, Tsuyoshi; Shiwaku, Hideaki; Suzuki, Shinichi

2008-11-01

The chlorination reaction of Y2O3 with ZrCl4 in LiCl-KCl eutectic melt was investigated by X-ray absorption fine structure (XAFS) technique. The chlorination reaction was observed between 773 K and 823 K as the 1st peak shift of the Fourier transform magnitude function |FT(k3χ(k))|. The peak corresponding to the nearest Y3+-Cl- correlation was observed in the XAFS analysis at 823 K as the result of the chlorination. It was confirmed that the mixture melts after the reaction is almost equivalent to a molten 5% YCl3-(LiCl-KCl eutectic) mixture.

Temperature dependence of luminescence behavior in Er3+-doped BaY2F8 single crystal

NASA Astrophysics Data System (ADS)

Wang, Shuai; Ruan, Yongfeng; Tsuboi, Taiju; Tong, Hongshuang; Wang, Youfa; Zhang, Shouchao

2013-12-01

BaY2F8 single crystals doped with Er3+ ions have been grown by the temperature gradient method. The absorption, excitation and emission spectra for Er3+-doped BaY2F8 crystals were measured at room temperature (297 K) and 12 K. The effect of temperature on the luminescence intensity and effective bandwidth was investigated in the range of 12-297 K. The temperature dependence of the fluorescence intensity ratio (FIR) for the 522 nm emission (2H11/2→4I15/2 transition) and the 552 nm emission (4S3/2→4I15/2 transition) was also studied in the range of 12-297 K. Based on the fitting FIR curve, the value of the constant term B (2.25) was obtained. The fitting FIR curve and FIR equation may have a potential application in the temperature measurement. In addition, the up-conversion spectrum at room temperature was recorded under excitation of 980 nm and the up-conversion mechanism was analyzed in detail.

Development of a Colloidal Gold-Based Immunochromatographic Strip for Rapid Detection of Klebsiella pneumoniae Serotypes K1 and K2

PubMed Central

Siu, L. Kristopher; Tsai, Yu-Kuo; Lin, Jung-Chung; Chen, Te-Li; Fung, Chang-Phone

2016-01-01

In this study, a novel colloidal gold-based immunochromatographic strip (ICS) containing anti-Klebsiella pneumoniae capsular polysaccharide polyclonal antibodies was developed to specifically detect K. pneumoniae serotypes K1 and K2. Capsular polysaccharide K1 and K2 antigens were first used to produce polyclonal anti-K1 and anti-K2 antibodies. Reference strains with different serotypes, nontypeable K. pneumoniae strains, and other bacterial species were then used to assess the sensitivity and specificity of these test strips. The detection limit was found to be 105 CFU, and the ICSs were stable for 6 months when stored at room temperature. No false-positive or false-negative results were observed, and equivalent results were obtained compared to those of more conventional test methods, such as PCR or serum agglutination. In conclusion, the ICS developed here requires no technical expertise and allows for the specific, rapid, and simultaneous detection of K. pneumoniae serotypes K1 and K2. PMID:27707941

Assessing the prevalence of trauma exposure in epidemiological surveys.

PubMed

Mills, Katherine L; McFarlane, Alexander C; Slade, Tim; Creamer, Mark; Silove, Derrick; Teesson, Maree; Bryant, Richard

2011-05-01

Estimates of the prevalence of exposure to potentially traumatic events (PTEs) in population surveys have increased over time. There is limited empirical evidence on the impact of changes in measurement practices on these estimates. The present study examined the effect of increasing the number of events assessed on the prevalence of exposure longitudinally. Data were ultilized from the 1997 and 2007 Australian National Surveys of Mental Health and Wellbeing. The 1997 survey assessed exposure using 11 items from the Composite International Diagnostic Interview (CIDI), version 2.1. The 2007 survey utilized 29 items from the World Mental Health CIDI. Prevalence rates of exposure to matched events among age-matched samples from both surveys were compared to determine whether differences in the estimates obtained were due to respondents having been asked about an increased number of event types in the latter survey. The effect of increasing the number of event types in the CIDI from 11 to 29 was to increase the overall population prevalence of exposure to PTEs by 18%. The difference between estimates was more pronounced in women than in men. The cross-cohort analyses revealed that these differences were not indicative of an increase in trauma exposure over time; but rather the endorsement of new events that were not listed in the earlier survey. The findings underscore the importance of using comprehensive assessments in the measurement of exposure to PTEs. Previous epidemiological surveys may have underestimated the prevalence of traumatic and other stressful life events, particularly among women.

Monitoring Progress: How the 2012 National Survey of Science and Mathematics Education Can Inform a National K-12 STEM Education Indicator System

ERIC Educational Resources Information Center

Fulkerson, William O.; Banilower, Eric R.

2014-01-01

"Monitoring Progress Toward Successful K-12 STEM Education: A Nation Advancing?" (National Research Council, 2013) describes a set of 14 indicators for assessing and tracking the health of pre-college STEM education in the United States. This 2012 National Survey of Science and Mathematics Education (NSSME), is the fifth in a series of…

Elevated temperature creep properties of NiAl cryomilled with and without Y2O3

NASA Technical Reports Server (NTRS)

Whittenberger, J. Daniel; Luton, Michael J.

1995-01-01

The creep properties of lots of NiAl cryomilled with and without Y2O3 have been determined in compression and tension. Although identical cryomilling procedures were used, differences in composition were found between the lot ground with 0.5 vol% yttria and the lot ground without Y2O3. Compression testing between 1000 and 1300 K yielded similar creep strengths for both materials, while tensile creep rupture testing indicated that the yttria-containing alloy was slightly stronger than the Y2O3-free version. Both compression and tensile testing showed two deformation regimes; whereas the stress state did not affect the high stress exponent (n approximately equals 10) mechanism, the low stress exponent regime n was approximately 6 in tension and approximately 2 in compression. The strengths in tension were somewhat less than those measured in compression, but the estimated activation energies (Q) of approximately 600 kJ/mol for tensile testing were closer to the previously measured values (approximately 700 kJ/mol) for NiAl-AlN and very different from the Q's of 400 and 200 kJ/mol for compression tests in the high and low stress exponent regimes, respectively. A Larson-Miller comparison indicated that cryomilling can produce an alloy with long-term, high-temperature strength at least equal to conventional superalloys.

Supernova Remnants in the UWIFE and UWISH2 Surveys

NASA Astrophysics Data System (ADS)

Lee, Yong-Hyun; Koo, Bon-Chul; Lee, Jae-Joon

2016-06-01

We have searched for near-infrared [Fe II] (1.644 µm) and H2 1-0 S(1) (2.122 µm) emission features associated with Galactic supernova remnants (SNRs) using the narrow-band imaging surveys UWIFE/ UWISH2 (UKIRT Widefield Infrared Survey for [Fe II] / H2). Both surveys cover about 180 square degrees of the first Galactic quadrant (7° < l < 62°; -1.5° < b < +1.5°), and a total of 79 SNRs are falling in the survey area among the currently known 294 Galactic SNRs. The images show diffuse structures as deep as the surface brightness limit of 10-19 W m-2 arcsec-2 which is comparable with a 5σ detection limit of point sources of 18 mag. In order to inspect the narrow-band features, we subtracted H and K-band continuum images obtained from the UKIDSS GPS (UKIRT Infrared Deep Sky Survey of the Galactic Plane) from the [Fe II] and H2 narrow-band images, respectively. By this time, we have found 19 [Fe II]- and 18 H2-emitting SNRs, and these are likely to increase in future as we inspect the images in more detail. Some of the SNRs show bright, complex, and interesting structures that have never been reported in previous studies. Since [Fe II] and H2 lines trace dense atomic and molecular gases associated with SNR shocks, our results can help us understand the environment and evolution of individual SNRs. Among the SNRs showing both [Fe II] and H2 emission lines, some SNRs show the “[Fe II]-H2 reversal” phenomenon, i.e., the H2 emission features are detected outside the [Fe II] emission boundary. This is opposite to the standard picture: If the shocks are driven by the same blast wave, we expect the H2 filaments to be closer to the explosion center than the [Fe II] filaments. In this presentation, we show several examples of such SNRs detected in our study, and present high resolution (R ˜ 40,000) H and K-band spectra of H2 emission features obtained by using IGRINS (Immersion Grating Infrared Spectrograph).

Supernova Remnants in the UWIFE and UWISH2 Surveys

NASA Astrophysics Data System (ADS)

Lee, Yong-Hyun

2016-06-01

We have searched for near-infrared [Fe II] (1.644 μm) and H2 1-0 S(1) (2.122 μm) emission features associated with Galactic supernova remnants (SNRs) using the narrow-band imaging surveys UWIFE/ UWISH2 (UKIRT Widefield Infrared Survey for [Fe II] / H2 ). Both surveys cover about 180 square degrees of the first Galactic quadrant (7 {circ} < l < 62 {circ} ; -1.5 {circ} < b < +1.5 {circ} ), and a total of 79 SNRs are falling in the survey area among the currently known 294 Galactic SNRs. The images show diffuse structures as deep as the surface brightness limit of 10^(-19) W m^(-2) arcsec^(-2) which is comparable with a 5σ detection limit of point sources of 18 mag. In order to inspect the narrow-band features, we subtracted H and K-band continuum images obtained from the UKIDSS GPS (UKIRT Infrared Deep Sky Survey of the Galactic Plane) from the [Fe II] and H2 narrow-band images, respectively. By this time, we have found 19 [Fe II]- and 18 H2 -emitting SNRs, and these are likely to increase in future as we inspect the images in more detail. Some of the SNRs show bright, complex, and interesting structures that have never been reported in previous studies. Since [Fe II] and H2 lines trace dense atomic and molecular gases associated with SNR shocks, our results can help us understand the environment and evolution of individual SNRs. Among the SNRs showing both [Fe II] and H2 emission lines, some SNRs show the “[Fe II]-H2 reversal” phenomenon, i.e., the H2 emission features are detected outside the [Fe II] emission boundary. This is opposite to the standard picture: If the shocks are driven by the same blast wave, we expect the H2 filaments to be closer to the explosion center than the [Fe II] filaments. In this presentation, we show several examples of such SNRs detected in our study, and present high resolution (R 40,000) H and K-band spectra of H2 emission features obtained by using IGRINS (Immersion Grating Infrared Spectrograph).

Benchmarking of energy consumption in municipal wastewater treatment plants - a survey of over 200 plants in Italy.

PubMed

Vaccari, M; Foladori, P; Nembrini, S; Vitali, F

2018-05-01

One of the largest surveys in Europe about energy consumption in Italian wastewater treatment plants (WWTPs) is presented, based on 241 WWTPs and a total population equivalent (PE) of more than 9,000,000 PE. The study contributes towards standardised resilient data and benchmarking and to identify potentials for energy savings. In the energy benchmark, three indicators were used: specific energy consumption expressed per population equivalents (kWh PE -1 year -1 ), per cubic meter (kWh/m 3 ), and per unit of chemical oxygen demand (COD) removed (kWh/kgCOD). The indicator kWh/m 3 , even though widely applied, resulted in a biased benchmark, because highly influenced by stormwater and infiltrations. Plants with combined networks (often used in Europe) showed an apparent better energy performance. Conversely, the indicator kWh PE -1 year -1 resulted in a more meaningful definition of a benchmark. High energy efficiency was associated with: (i) large capacity of the plant, (ii) higher COD concentration in wastewater, (iii) separate sewer systems, (iv) capacity utilisation over 80%, and (v) high organic loads, but without overloading. The 25th percentile was proposed as a benchmark for four size classes: 23 kWh PE -1 y -1 for large plants > 100,000 PE; 42 kWh PE -1 y -1 for capacity 10,000 < PE < 100,000, 48 kWh PE -1 y -1 for capacity 2,000 < PE < 10,000 and 76 kWh PE -1 y -1 for small plants < 2,000 PE.

Phosphatidylinositol (4,5)-bisphosphate dynamically regulates the K2P background K+ channel TASK-2

PubMed Central

Niemeyer, María Isabel; Cid, L. Pablo; Paulais, Marc; Teulon, Jacques; Sepúlveda, Francisco V.

2017-01-01

Two-pore domain K2P K+ channels responsible for the background K+ conductance and the resting membrane potential, are also finely regulated by a variety of chemical, physical and physiological stimuli. Hormones and transmitters acting through Gq protein-coupled receptors (GqPCRs) modulate the activity of various K2P channels but the signalling involved has remained elusive, in particular whether dynamic regulation by membrane PI(4,5)P2, common among other classes of K+ channels, affects K2P channels is controversial. Here we show that K2P K+ channel TASK-2 requires PI(4,5)P2 for activity, a dependence that accounts for its run down in the absence of intracellular ATP and its full recovery by addition of exogenous PI(4,5)P2, its inhibition by low concentrations of polycation PI scavengers, and inhibition by PI(4,5)P2 depletion from the membrane. Comprehensive mutagenesis suggests that PI(4,5)P2 interaction with TASK-2 takes place at C-terminus where three basic aminoacids are identified as being part of a putative binding site. PMID:28358046

Phosphatidylinositol (4,5)-bisphosphate dynamically regulates the K2P background K+ channel TASK-2.

PubMed

Niemeyer, María Isabel; Cid, L Pablo; Paulais, Marc; Teulon, Jacques; Sepúlveda, Francisco V

2017-03-30

Two-pore domain K 2P K + channels responsible for the background K + conductance and the resting membrane potential, are also finely regulated by a variety of chemical, physical and physiological stimuli. Hormones and transmitters acting through Gq protein-coupled receptors (GqPCRs) modulate the activity of various K 2P channels but the signalling involved has remained elusive, in particular whether dynamic regulation by membrane PI(4,5)P 2 , common among other classes of K + channels, affects K 2P channels is controversial. Here we show that K 2P K + channel TASK-2 requires PI(4,5)P 2 for activity, a dependence that accounts for its run down in the absence of intracellular ATP and its full recovery by addition of exogenous PI(4,5)P 2 , its inhibition by low concentrations of polycation PI scavengers, and inhibition by PI(4,5)P 2 depletion from the membrane. Comprehensive mutagenesis suggests that PI(4,5)P 2 interaction with TASK-2 takes place at C-terminus where three basic aminoacids are identified as being part of a putative binding site.

Multiple composite grafts (k, π or double-Y) in coronary artery surgery: a choice or a necessity?

PubMed

Mannacio, Vito; Cirillo, Plinio; Mannacio, Luigi; Antignano, Anita; Mottola, Michele; Vosa, Carlo

2015-01-01

Composite grafts allow complete arterial revascularization with minimal aortic manipulations. The Y-T configuration supplies all distal branches adequately, whereas it is unclear whether complex composite configurations (K, Π or double-Y) are equally at rest or when challenged by maximal requirements. Forty-seven patients who underwent off-pump coronary artery revascularization by multiple arterial composite grafts (K, Π or double-Y) were retrospectively evaluated. Indication for this surgical option was porcelain aorta or conduit unavailability. Composite systems were evaluated by intraoperative flow measurements and perioperative transthoracic Doppler ultrasonography, 12 months later also by exercise test, sestamibi scintigraphy at rest and during induced hyperaemia and by 64-slice multidetector CT angiography. A total of 141 distal anastomoses were implanted as composite grafts. Perioperative flow measurements and 12-month Doppler ultrasonography were adequate at rest. At stress test, chest pain and/or induced ECG evidence of ischaemia are found in 16 patients (39%). During dipyridamole-induced hyperaemia, single-photon emission computed tomography image revealed that mean summed stress score was 7.2 ± 5.7, summed difference score 5.3 ± 4.2 and coronary flow reserve 1.7 ± 0.2. Multiple composite grafts, albeit adequate at rest, were unable to meet flow requirements during maximal hyperaemia. In daily practice, their use must be not a choice but rather a necessity in those patients without alternative options. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

k2photometry: Read, reduce and detrend K2 photometry

NASA Astrophysics Data System (ADS)

Van Eylen, Vincent; Nowak, Grzegorz; Albrecht, Simon; Palle, Enric; Ribas, Ignasi; Bruntt, Hans; Perger, Manuel; Gandolfi, Davide; Hirano, Teriyuki; Sanchis-Ojeda, Roberto; Kiilerich, Amanda; Arranz, Jorge P.; Badenas, Mariona; Dai, Fei; Deeg, Hans J.; Guenther, Eike W.; Montanes-Rodriguez, Pilar; Narita, Norio; Rogers, Leslie A.; Bejar, Victor J. S.; Shrotriya, Tushar S.; Winn, Joshua N.; Sebastian, Daniel

2016-02-01

k2photometry reads, reduces and detrends K2 photometry and searches for transiting planets. MAST database pixel files are used as input; the output includes raw lightcurves, detrended lightcurves and a transit search can be performed as well. Stellar variability is not typically well-preserved but parameters can be tweaked to change that. The BLS algorithm used to detect periodic events is a Python implementation by Ruth Angus and Dan Foreman-Mackey (https://github.com/dfm/python-bls).

Menzerite-(Y) a New Species {(Y REE)(Ca Fe2plus)2}[(Mg Fe2plus)(Fe3plus Al)](Si3)O12 from a Felsic Granulite Parry Sound Ontario and a New Garnet End-member (Y2Ca)Mg2(SiO4)3

DOE Office of Scientific and Technical Information (OSTI.GOV)

E Grew; J Marsh; M Yates

2011-12-31

Menzerite-(Y), a new mineral species, forms reddish brown cores, n = 1.844 (20), up to 70 {micro}m across, rimmed successively by euhedral almandine containing up to 2.7 wt% Y{sub 2}O{sub 3} and by K-feldspar in a felsic granulite on Bonnet Island in the interior Parry Sound domain, Grenville Orogenic Province, Canada. It is named after Georg Menzer (1897-1989), the German crystallographer who solved the crystal structure of garnet. Single-crystal X-ray-diffraction results yielded space group Ia3d, a = 11.9947(6) {angstrom}. An electron-microprobe analysis of the grain richest in Y (16.93 wt% Y{sub 2}O{sub 3}) gave the following formula, normalized to eightmore » cations and 12 oxygen atoms: {l_brace}Y{sub 0.83}Gd{sub 0.01}Dy{sub 0.05}Ho{sub 0.02}Er{sub 0.07}Tm{sub 0.01}Yb{sub 0.06}Lu{sub 0.02}Ca{sub 1.37}Fe{sub 0.49}{sup 2+}Mn{sub 0.07}{r_brace} [Mg{sub 0.55}Fe{sub 0.42}{sup 2+}Fe{sub 0.58}{sup 3+}Al{sub 0.35} V{sub 0.01}Sc{sub 0.01}Ti{sub 0.08}](Si{sub 2.82}Al{sub 0.18})O{sub 12}, or {l_brace}(Y,REE)(Ca,Fe{sup 2+}){sub 2}{r_brace}[(Mg,Fe{sup 2+})(Fe{sup 3+},Al)](Si{sub 3})O{sub 12}. Synchrotron micro-XANES data gave Fe{sup 3+}/{Sigma}Fe = 0.56(10) versus 0.39(2) calculated from stoichiometry. The scattering power refined at the octahedral Y site, 17.68 epfu, indicates that a relatively light element contributes to its occupancy. Magnesium, as determined by electron-microprobe analyses, would be a proper candidate. In addition, considering the complex occupancy of this site, the average Y-O bond length of 2.0244(16) {angstrom} is in accord with a partial occupancy by Mg. The dominance of divalent cations with Mg > Fe{sup 2+} and the absence of Si at the octahedral Y site (in square brackets) are the primary criteria for distinguishing menzerite-(Y) from other silicate garnet species; the menzerite-(Y) end-member is {l_brace}Y{sub 2}Ca{r_brace}[Mg{sub 2}](Si{sub 3})O{sub 12}. The contacts of menzerite-(Y) with almandine are generally sharp and, in places, cuspate

Identifying the Volcanic Eruption Depicted in a Neolithic Painting at Çatalhöyük, Central Anatolia, Turkey

PubMed Central

Schmitt, Axel K.; Danišík, Martin; Aydar, Erkan; Şen, Erdal; Ulusoy, İnan; Lovera, Oscar M.

2014-01-01

A mural excavated at the Neolithic Çatalhöyük site (Central Anatolia, Turkey) has been interpreted as the oldest known map. Dating to ∼6600 BCE, it putatively depicts an explosive summit eruption of the Hasan Dağı twin-peaks volcano located ∼130 km northeast of Çatalhöyük, and a birds-eye view of a town plan in the foreground. This interpretation, however, has remained controversial not least because independent evidence for a contemporaneous explosive volcanic eruption of Hasan Dağı has been lacking. Here, we document the presence of andesitic pumice veneer on the summit of Hasan Dağı, which we dated using (U-Th)/He zircon geochronology. The (U-Th)/He zircon eruption age of 8.97±0.64 ka (or 6960±640 BCE; uncertainties 2σ) overlaps closely with 14C ages for cultural strata at Çatalhöyük, including level VII containing the “map” mural. A second pumice sample from a surficial deposit near the base of Hasan Dağı records an older explosive eruption at 28.9±1.5 ka. U-Th zircon crystallization ages in both samples range from near-eruption to secular equilibrium (>380 ka). Collectively, our results reveal protracted intrusive activity at Hasan Dağı punctuated by explosive venting, and provide the first radiometric ages for a Holocene explosive eruption which was most likely witnessed by humans in the area. Geologic and geochronologic lines of evidence thus support previous interpretations that residents of Çatalhöyük artistically represented an explosive eruption of Hasan Dağı volcano. The magmatic longevity recorded by quasi-continuous zircon crystallization coupled with new evidence for late-Pleistocene and Holocene explosive eruptions implicates Hasan Dağı as a potential volcanic hazard. PMID:24416270

The 2.3 GHz continuum survey of the GEM project

NASA Astrophysics Data System (ADS)

Tello, C.; Villela, T.; Torres, S.; Bersanelli, M.; Smoot, G. F.; Ferreira, I. S.; Cingoz, A.; Lamb, J.; Barbosa, D.; Perez-Becker, D.; Ricciardi, S.; Currivan, J. A.; Platania, P.; Maino, D.

2013-08-01

Context. Determining the spectral and spatial characteristics of the radio continuum of our Galaxy is an experimentally challenging endeavour for improving our understanding of the astrophysics of the interstellar medium. This knowledge has also become of paramount significance for cosmology, since Galactic emission is the main source of astrophysical contamination in measurements of the cosmic microwave background (CMB) radiation on large angular scales. Aims: We present a partial-sky survey of the radio continuum at 2.3GHz within the scope of the Galactic Emission Mapping (GEM) project, an observational program conceived and developed to reveal the large-scale properties of Galactic synchrotron radiation through a set of self-consistent surveys of the radio continuum between 408MHz and 10GHz. Methods: The GEM experiment uses a portable and double-shielded 5.5-m radiotelescope in altazimuthal configuration to map 60-degree-wide declination bands from different observational sites by circularly scanning the sky at zenithal angles of 30° from a constantly rotating platform. The observations were accomplished with a total power receiver, whose front-end high electron mobility transistor (HEMT) amplifier was matched directly to a cylindrical horn at the prime focus of the parabolic reflector. The Moon was used to calibrate the antenna temperature scale and the preparation of the map required direct subtraction and destriping algorithms to remove ground contamination as the most significant source of systematic error. Results: We used 484 h of total intensity observations from two locations in Colombia and Brazil to yield 66% sky coverage from to . The observations in Colombia were obtained with a horizontal HPBW of and a vertical HPBW of . The pointing accuracy was and the RMS sensitivity was 11.42 mK. The observations in Brazil were obtained with a horizontal HPBW of and a vertical HPBW of . The pointing accuracy was and the RMS sensitivity was 8.24 mK. The zero

Long range intermolecular interactions between the alkali diatomics Na2, K2, and NaK

NASA Astrophysics Data System (ADS)

Zemke, Warren T.; Byrd, Jason N.; Michels, H. Harvey; Montgomery, John A.; Stwalley, William C.

2010-06-01

Long range interactions between the ground state alkali diatomics Na2-Na2, K2-K2, Na2-K2, and NaK-NaK are examined. Interaction energies are first determined from ab initio calculations at the coupled-cluster with singles, doubles, and perturbative triples [CCSD(T)] level of theory, including counterpoise corrections. Long range energies calculated from diatomic molecular properties (polarizabilities and dipole and quadrupole moments) are then compared with the ab initio energies. A simple asymptotic model potential ELR=Eelec+Edisp+Eind is shown to accurately represent the intermolecular interactions for these systems at long range.

A systematic review of childhood maltreatment assessments in population-representative surveys since 1990.

PubMed

Hovdestad, Wendy; Campeau, Aimée; Potter, Dawn; Tonmyr, Lil

2015-01-01

Population-representative surveys that assess childhood maltreatment and health are a valuable resource to explore the implications of child maltreatment for population health. Systematic identification and evaluation of such surveys is needed to facilitate optimal use of their data and to inform future research. To inform researchers of the existence and nature of population-representative surveys relevant to understanding links between childhood maltreatment and health; to evaluate the assessment of childhood maltreatment in this body of work. We included surveys that: 1) were representative of the non-institutionalized population of any size nation or of any geopolitical region ≥ 10 million people; 2) included a broad age range (≥ 40 years); 3) measured health; 4) assessed childhood maltreatment retrospectively; and 5) were conducted since 1990. We used Internet and database searching (including CINAHL, Embase, ERIC, Global Health, MEDLINE, PsycINFO, Scopus, Social Policy and Practice: January 1990 to March 2014), expert consultation, and other means to identify surveys and associated documentation. Translations of non-English survey content were verified by fluent readers of survey languages. We developed checklists to abstract and evaluate childhood maltreatment content. Fifty-four surveys from 39 countries met inclusion criteria. Sample sizes ranged from 1,287-51,945 and response rates from 15%-96%. Thirteen surveys assessed neglect, 15 emotional abuse; 18 exposure to family violence; 26 physical abuse; 48 sexual abuse. Fourteen surveys assessed more than three types; six of these were conducted since 2010. In nine surveys childhood maltreatment assessments were detailed (+10 items for at least one type of maltreatment). Seven surveys' assessments had known reliability and/or validity. Data from 54 surveys can be used to explore the population health relevance of child maltreatment. Assessment of childhood maltreatment is not comprehensive but there is

Calculation of Phase Equilibria in the Y2O3-Yb2O3-ZrO2 System

NASA Technical Reports Server (NTRS)

Jacobson, Nathan S.; Liu, Zi-Kui; Kaufman, Larry; Zhang, Fan

2001-01-01

Rare earth oxide stabilized zirconias find a wide range of applications. An understanding of phase equilibria is essential to all applications. In this study, the available phase boundary data and thermodynamic data is collected and assessed. Calphad-type databases are developed to completely describe the Y2O3-ZrO2, Yb2O3-ZrO2, and Y2O3-Yb2O3 systems. The oxide units are treated as components and regular and subregular solution models are used. The resultant calculated phase diagrams show good agreement with the experimental data. Then the binaries are combined to form the database for the Y2O3-Yb2O3-ZrO2 psuedo-ternary.

VizieR Online Data Catalog: High quality Spitzer/MIPS obs. of F4-K2 stars (Sierchio+, 2014)

NASA Astrophysics Data System (ADS)

Sierchio, J. M.; Rieke, G. H.; Su, K. Y. L.; Gaspar, A.

2016-11-01

We used specific criteria to draw samples of stars from the entire Spitzer Debris Disk Database (see section 2.1.1). V magnitudes were taken from Hipparcos and transformed to Johnson V. All stars were also required to have observations on the Two Micron All Sky Survey (2MASS) Ks system. Additional measurements were obtained at SAAO on the 0.75m telescope using the MarkII Infrared Photometer (transformed as described by Koen et al. 2007MNRAS.380.1433K), and at the Steward Observatory 61 in telescope using a NICMOS2-based camera with a 2MASS filter set and a neutral density filter to avoid saturation. These measurements will be described in a forthcoming paper (K. Y. L. Su et al., in preparation). The original programs in which our sample stars were measured are identified in Table 1. A large majority (93%) come from seven Spitzer programs: (1) the MIPS Guaranteed Time Observer (GTO) Sun-like star observations (Trilling+ 2008ApJ...674.1086T); (2) Formation and Evolution of Planetary Systems (FEPS; Meyer+ 2006, J/PASP/118/1690); (3) Completing the Census of Debris Disks (Koerner+ 2010ApJ...710L..26K); (4) potential Space Interferometry Mission/Terrestrial Planet Finder (SIM/TPF) targets (Beichman+ 2006ApJ...652.1674B); (5) an unbiased sample of F-stars (Trilling+ 2008ApJ...674.1086T); and (6) two coordinated programs selecting stars on the basis of indicators of youth (Low+ 2005ApJ...631.1170L; Plavchan+ 2009ApJ...698.1068P). See section 2.1.2. (1 data file).

Reinvestigation of the uranium(3.5+) rare-earth oxysulfides "(UO)2LnS3" (Ln = Yb, Y).

PubMed

Jin, Geng Bang; Choi, Eun Sang; Ibers, James A

2009-09-07

Dark-red square plates of the previously reported compounds "(UO)(2)LnS(3)" (Ln = Yb, Y) have been synthesized by solid-state reactions of UOS and YbS or Y(2)S(3) with Sb(2)S(3) as a flux at 1273 K. The structure of these isotypic compounds was reinvestigated by single-crystal X-ray diffraction methods and an inductively coupled plasma experiment. The actual formula of "(UO)(2)LnS(3)" (Ln = Yb, Y) is (U(0.5)Ln(0.5)O)(2)LnS(3), that is, ULn(2)O(2)S(3), which can be charge-balanced with U(4+) and Ln(3+). The layered structure comprises (U/Ln)O(4)S(4) square antiprisms alternating with LnS(6) octahedra. U and Ln1 atoms disorder on the eight-coordinate metal position, but Ln2 atoms occupy the six-coordinate metal position exclusively. UYb(2)O(2)S(3) is a modified Curie-Weiss paramagnet between 293 and 32 K, below which part of the paramagnetic moments go through a possible ferromagnetic transition. The band gaps of ULn(2)O(2)S(3) (Ln = Yb, Y) are around 2 eV.

The influence of apical oxygen on the increase of Tc in Y Ba2Cu3O7-X

NASA Astrophysics Data System (ADS)

Dul'kin, E.

2004-07-01

The direct current (DC) bulk resistance and acoustic emission of Y Ba2Cu3O7-X ceramic samples have simultaneously been measured during heating in a temperature region of 400-700 K. Near 560 K, an anomaly of rgr, accompanied by an acoustic emission, has been observed. After this anomaly rgr reached a lower value than had previously been measured. The observed rgr decrease and acoustic emission signals confirm that Y Ba2Cu3O7-X ceramic samples absorb oxygen during heating in the temperature region of 500-600 K, as shown by previous dilatometric measurements (Dul'kin 2001 J. Superconductivity 14 497). It is shown that absorbed oxygen atoms enter O4 apical oxygen sites and are able to increase the Tc in Y Ba2Cu3O7-X material.

Development of a Colloidal Gold-Based Immunochromatographic Strip for Rapid Detection of Klebsiella pneumoniae Serotypes K1 and K2.

PubMed

Siu, L Kristopher; Tsai, Yu-Kuo; Lin, Jung-Chung; Chen, Te-Li; Fung, Chang-Phone; Chang, Feng-Yee

2016-12-01

In this study, a novel colloidal gold-based immunochromatographic strip (ICS) containing anti-Klebsiella pneumoniae capsular polysaccharide polyclonal antibodies was developed to specifically detect K. pneumoniae serotypes K1 and K2. Capsular polysaccharide K1 and K2 antigens were first used to produce polyclonal anti-K1 and anti-K2 antibodies. Reference strains with different serotypes, nontypeable K. pneumoniae strains, and other bacterial species were then used to assess the sensitivity and specificity of these test strips. The detection limit was found to be 10 5 CFU, and the ICSs were stable for 6 months when stored at room temperature. No false-positive or false-negative results were observed, and equivalent results were obtained compared to those of more conventional test methods, such as PCR or serum agglutination. In conclusion, the ICS developed here requires no technical expertise and allows for the specific, rapid, and simultaneous detection of K. pneumoniae serotypes K1 and K2. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

In vitro and in vivo characterization of JNJ-31020028 (N-(4-{4-[2-(diethylamino)-2-oxo-1-phenylethyl]piperazin-1-yl}-3-fluorophenyl)-2-pyridin-3-ylbenzamide), a selective brain penetrant small molecule antagonist of the neuropeptide Y Y(2) receptor.

PubMed

Shoblock, James R; Welty, Natalie; Nepomuceno, Diane; Lord, Brian; Aluisio, Leah; Fraser, Ian; Motley, S Timothy; Sutton, Steve W; Morton, Kirsten; Galici, Ruggero; Atack, John R; Dvorak, Lisa; Swanson, Devin M; Carruthers, Nicholas I; Dvorak, Curt; Lovenberg, Timothy W; Bonaventure, Pascal

2010-02-01

The lack of potent, selective, brain penetrant Y(2) receptor antagonists has hampered in vivo functional studies of this receptor. Here, we report the in vitro and in vivo characterization of JNJ-31020028 (N-(4-{4-[2-(diethylamino)-2-oxo-1-phenylethyl]piperazin-1-yl}-3-fluorophenyl)-2-pyridin-3-ylbenzamide), a novel Y(2) receptor antagonist. The affinity of JNJ-31020028 was determined by inhibition of the PYY binding to human Y(2) receptors in KAN-Ts cells and rat Y(2) receptors in rat hippocampus. The functional activity was determined by inhibition of PYY-stimulated calcium responses in KAN-Ts cells expressing a chimeric G protein Gqi5 and in the rat vas deferens (a prototypical Y(2) bioassay). Ex vivo receptor occupancy was revealed by receptor autoradiography. JNJ-31020028 was tested in vivo with microdialysis, in anxiety models, and on corticosterone release. JNJ-31020028 bound with high affinity (pIC(50) = 8.07 +/- 0.05, human, and pIC(50) = 8.22 +/- 0.06, rat) and was >100-fold selective versus human Y(1), Y(4), and Y(5) receptors. JNJ-31020028 was demonstrated to be an antagonist (pK(B) = 8.04 +/- 0.13) in functional assays. JNJ-31020028 occupied Y(2) receptor binding sites (approximately 90% at 10 mg/kg) after subcutaneous administration in rats. JNJ-31020028 increased norepinephrine release in the hypothalamus, consistent with the colocalization of norepinephrine and neuropeptide Y. In a variety of anxiety models, JNJ-31020028 was found to be ineffective, although it did block stress-induced elevations in plasma corticosterone, without altering basal levels, and normalized food intake in stressed animals without affecting basal food intake. These results suggest that Y(2) receptors may not be critical for acute behaviors in rodents but may serve modulatory roles that can only be elucidated under specific situational conditions.

Optical, Structural and Paramagnetic Properties of Eu-Doped Ternary Sulfides ALnS2 (A = Na, K, Rb; Ln = La, Gd, Lu, Y)

PubMed Central

Jarý, Vítězslav; Havlák, Lubomír; Bárta, Jan; Buryi, Maksym; Mihóková, Eva; Rejman, Martin; Laguta, Valentin; Nikl, Martin

2015-01-01

Eu-doped ternary sulfides of general formula ALnS2 (A = Na, K, Rb; Ln = La, Gd, Lu, Y) are presented as a novel interesting material family which may find usage as X-ray phosphors or solid state white light emitting diode (LED) lighting. Samples were synthesized in the form of transparent crystalline hexagonal platelets by chemical reaction under the flow of hydrogen sulfide. Their physical properties were investigated by means of X-ray diffraction, time-resolved photoluminescence spectroscopy, electron paramagnetic resonance, and X-ray excited fluorescence. Corresponding characteristics, including absorption, radioluminescence, photoluminescence excitation and emission spectra, and decay kinetics curves, were measured and evaluated in a broad temperature range (8–800 K). Calculations including quantum local crystal field potential and spin-Hamiltonian for a paramagnetic particle in D3d local symmetry and phenomenological model dealing with excited state dynamics were performed to explain the experimentally observed features. Based on the results, an energy diagram of lanthanide energy levels in KLuS2 is proposed. Color model xy-coordinates are used to compare effects of dopants on the resulting spectrum. The application potential of the mentioned compounds in the field of white LED solid state lighting or X-ray phosphors is thoroughly discussed. PMID:28793612

K2 and K2*: efficient alignment-free sequence similarity measurement based on Kendall statistics.

PubMed

Lin, Jie; Adjeroh, Donald A; Jiang, Bing-Hua; Jiang, Yue

2018-05-15

Alignment-free sequence comparison methods can compute the pairwise similarity between a huge number of sequences much faster than sequence-alignment based methods. We propose a new non-parametric alignment-free sequence comparison method, called K2, based on the Kendall statistics. Comparing to the other state-of-the-art alignment-free comparison methods, K2 demonstrates competitive performance in generating the phylogenetic tree, in evaluating functionally related regulatory sequences, and in computing the edit distance (similarity/dissimilarity) between sequences. Furthermore, the K2 approach is much faster than the other methods. An improved method, K2*, is also proposed, which is able to determine the appropriate algorithmic parameter (length) automatically, without first considering different values. Comparative analysis with the state-of-the-art alignment-free sequence similarity methods demonstrates the superiority of the proposed approaches, especially with increasing sequence length, or increasing dataset sizes. The K2 and K2* approaches are implemented in the R language as a package and is freely available for open access (http://community.wvu.edu/daadjeroh/projects/K2/K2_1.0.tar.gz). yueljiang@163.com. Supplementary data are available at Bioinformatics online.

EVEREST: Pixel Level Decorrelation of K2 Light Curves