Sample records for coster-kronig transitions

  1. Coster-Kronig transition probability f23 in gold atoms

    NASA Astrophysics Data System (ADS)

    Dunford, R. W.; Kanter, E. P.; Krässig, B.; Southworth, S. H.; Young, L.; Mokler, P. H.; Stöhlker, Th.; Cheng, S.; Kochur, A. G.; Petrov, I. D.

    2006-12-01

    We have investigated the Coster-Kronig transition probability f23 in gold atoms (nuclear charge Z=79 ) using the L x-ray versus K x-ray coincidence method. K vacancies were created using synchrotron radiation and the cascade decays were measured using germanium x-ray detectors. We find f23=0.112±0.004 which is somewhat lower than the recent coincidence measurement of Santra which yielded f23=0.119±0.003 . Our result is smaller than the values calculated by McGuire (f23=0.132) and Puri (f23=0.129) but agrees with our own single-configuration Pauli-Fock calculation, which gives f23=0.114 , as well as the global set of prior experimental data.

  2. X-Ray Fluorescence Yields, Auger, and Coster-Kronig Transition Probabilities

    Microsoft Academic Search

    Walter Bambynek; Bernd Crasemann; R. W. Fink; H.-U. Freund; Hans Mark; C. D. Swift; R. E. Price; P. Venugopala Rao

    1972-01-01

    The present status of the field of fluorescence yields, radiationless (Auger and Coster-Kronig) and radiative transition probabilities is summarized. Tables of experimental and theoretical results are included, and tables of \\

  3. Investigation of low-Z Coster-Kronig transitions by means of Auger and photoelectron spectroscopy

    NASA Technical Reports Server (NTRS)

    Yin, L. I.; Tsang, T.; Adler, I.

    1972-01-01

    Experimental intensity ratios of Auger transitions for Co, Ni, Cu, and Zn as well as the relative L sub 2 and L sub 3 level widths of Cu and Zn, derived from their photoelectron spectra, are presented. Evidence is presented that a great deal of vacancy reorganization took place following photoionization and prior to Auger emission. These reorganizations are assumed to be due to Coster-Kronig transitions f sub 23. These results are compared with theoretical calculations and agree with predicted discontinuity at Z = 30 where f sub 23 transitions become energetically impossible.

  4. Coster-Kronig transition probability f{sub 23} in gold atoms

    SciTech Connect

    Dunford, R. W.; Kanter, E. P.; Kraessig, B.; Southworth, S. H.; Young, L. [Argonne National Laboratory, Argonne, Illinois 60439 (United States); Mokler, P. H. [Institut fur Atom- and Molekuelphysik, Justus-Liebig University, D35392 Giessen (Germany); GSI, Planckstrasse 1, D64291 Darmstadt (Germany); Stoehlker, Th. [GSI, Planckstrasse 1, D64291 Darmstadt (Germany); Cheng, S. [Department of Physics, University of Toledo, Toledo, Ohio 43606 (United States); Kochur, A. G.; Petrov, I. D. [Rostov State University of Transport Communication, Rostov-na-Donu, 344038 (Russian Federation)

    2006-12-15

    We have investigated the Coster-Kronig transition probability f{sub 23} in gold atoms (nuclear charge Z=79) using the L x-ray versus K x-ray coincidence method. K vacancies were created using synchrotron radiation and the cascade decays were measured using germanium x-ray detectors. We find f{sub 23}=0.112{+-}0.004 which is somewhat lower than the recent coincidence measurement of Santra et al. which yielded f{sub 23}=0.119{+-}0.003. Our result is smaller than the values calculated by McGuire (f{sub 23}=0.132) and Puri et al. (f{sub 23}=0.129) but agrees with our own single-configuration Pauli-Fock calculation, which gives f{sub 23}=0.114, as well as the global set of prior experimental data.

  5. L-subshell fluorescence yields and Coster-Kronig transition probabilities with a reliable uncertainty budget for selected high- and medium-Z elements

    NASA Astrophysics Data System (ADS)

    Kolbe, Michael; Hönicke, Philipp; Müller, Matthias; Beckhoff, Burkhard

    2012-10-01

    Photon-in/photon-out experiments at thin specimens have been carried out to determine L-subshell fluorescence yields as well as Coster-Kronig transition probabilities of Au, Pb, Mo, and Pd using radiometrically calibrated instrumentation in the Physikalisch-Technische Bundesanstalt (PTB) laboratory at the electron storage ring BESSY II in Berlin. An advanced approach was developed in order to derive the fluorescence line intensities by means of line sets of each subshell that were corrected for self-absorption and broadened with experimentally determined detector response functions. The respective photoelectric cross sections for each subshell were determined by means of transmission measurements of the same samples without any change in the experimental operating condition. All values derived were compared to those of earlier works. A completely traceable uncertainty budget is provided for the determined values.

  6. Relativistic L -shell Auger and Coster-Kronig rates and fluorescence yields

    NASA Technical Reports Server (NTRS)

    Chen, M. H.; Laiman, E.; Crasemann, B.; Aoyagi, M.; Mark, H.

    1979-01-01

    Relativistic calculations of radiationless transition rates to L -subshell vacancy states in selected atoms with Z in the 70-96 range have been performed. The Auger and Coster-Kronig transition probabilities are calculated from perturbation theory, assuming frozen orbitals, in the Dirac-Hartree-Slater approach. Transition rates, fluorescence yields, and Coster-Kronig yields are compared with nonrelativistic theoretical results and with experiment. Relativity is found to affect the L -subshell Auger widths by (10-25)% and individual transition rates to certain j-j configurations by as much as 40% at Z = 80. The widths of L sub i vacancy states and the L sub 2 Coster-Kronig yields f33 from these relativistic calculations agree much better with experiment than earlier nonrelativistic theoretical values.

  7. Auger and Coster-Kronig radial matrix elements for atomic numbers 6 le Z le 92

    SciTech Connect

    Chen, Mau Hsiung (Lawrence Livermore National Laboratory, CA (USA)); Larkins, F.P. (Univ. of Tasmania, Hobart (Australia)); Crasemann, B. (Univ. of Oregon, Eugene (USA))

    1990-05-01

    Coulomb radial matrix elements for Auger and Coster-Kronig transitions to K-, L{sub 1}-, L{sub 2}-, and L{sub 3}-shell vacancies in singly ionized atoms have been calculated with relativistic Dirac-Hartree-Slater wave functions. Results are tabulated for atomic numbers Z = 6-87 for the K shell and Z = 12-92 for the L subshells. These matrix elements can be used to calculate approximate Auger rates in multiply ionized atoms; the matrix elements are expected to be very useful for the computation of Auger rates in molecules and can be applied in computations of valence-band Auger lineshapes in solids.

  8. Measurement of atomic L shell Coster-Kronig yields (f12, f23 and f13) for some elements in the atomic number range 59?Z?90

    NASA Astrophysics Data System (ADS)

    Öz, Elif; Ekinci, Neslihan; Özdemir, Yüksel; Ertugrul, Mehmet; Sahin, Yusuf; Erdogan, Hasan

    2001-02-01

    Non-radiative transitions cause changes in the generation of the intensity of the L lines. In order to investigate the physical quantities relevant to the L lines affected by the non-radiative transitions, experimental measurements were carried out using a Si(Li) x-ray spectrometer. Atomic L shell Coster-Kronig yields (f12, f13 and f23) for some elements in the atomic number range 59?Z?90 were determined. These selected measured semi-empirical values were also fitted by least squares to polynomials in Z of the form ?nanZn (except for f13) and compared with theoretical and with earlier fitted values.

  9. M i ( i = 1-5) subshell fluorescence and Coster-Kronig yields for elements with 67 ? Z ? 92

    NASA Astrophysics Data System (ADS)

    Chauhan, Yogeshwar; Puri, Sanjiv

    2008-01-01

    A complete set of the M i ( i = 1-5) subshell fluorescence and Coster-Kronig (CK) yields has been generated by interpolation for elements with 67 ? Z ? 92 from the Dirac-Hartree-Slater (DHS) model based values tabulated for a limited number of elements, considering the cutoff/onset of different CK transitions in accordance with the CK transition energies evaluated in the present work. The CK transition energies have been deduced from tabulated values of the Dirac-Hartree-Fock-Slater model based neutral atom binding energies [K. Huang, M. Aoyagi, M.H. Chen, B. Crasemann, H. Mark, At. Data Nucl. Data Tables 18 (1976) 243] and the L i ( i = 1-3) subshell CK transition energies [M.H. Chen, B. Crasemann, K. Huang, M. Aoyagi, H. Mark, At. Data Nucl. Data Tables 19 (1977) 97] in order to establish the cutoff/onset of different CK transitions at specific atomic numbers. A second set of the M i ( i = 1-5) subshell fluorescence yields have also been deduced using radiative widths computed from the Dirac-Fock (DF) model based X-ray emission rates, and the total widths reevaluated to incorporate the DF model based radiative widths in place of those based on the DHS model. Further, the CK-corrected ( ?i) and average fluorescence ( ?M) fields, which are experimentally important, have been evaluated from the generated set of CK yields and two sets of fluorescence yields.

  10. Fluorescence and Coster - Kronig Yields of L Subshells in Hg from the Decay of 198Au and 204Tl

    Microsoft Academic Search

    J. M. Palms; R. E. Wood; P. Venugopala Rao; V. O. Kostroun

    1970-01-01

    Coincidences between L x rays and Kalpha x rays, emitted during the filling of K and L vacancies in Hg in the decay of 198Au and 204Tl, are measured with high-resolution Si(Li) and Ge(Li) x-ray spectrometers in a fast-coincidence arrangement. The following L-subshell fluorescence and Coster-Kronig yields are measured: omega2=0.316+\\/-0.010, omega3=0.300+\\/-0.010, and f23=0.190+\\/-0.010.

  11. L -subshell Coster-Kronig yields of palladium determined via synchrotron-radiation-based high-resolution x-ray spectroscopy

    NASA Astrophysics Data System (ADS)

    Cao, W.; Hoszowska, J.; Dousse, J.-Cl.; Kayser, Y.; Kav?i?, M.; Žitnik, M.; Bu?ar, K.; Miheli?, A.; Szlachetko, J.; S?abkowska, K.

    2009-07-01

    We report on the experimental determination of the palladium L -subshell Coster-Kronig (CK) transition yields via high-resolution measurements of the L?1,2 (L3-M4,5) and L?1 (L2-M4) x-ray emission lines. The L x-ray spectra were recorded by means of curved crystal spectrometers employing energy-tunable synchrotron radiation for fluorescence production. The CK yields were derived from the relative L x-ray intensity jumps at the L edges by fitting the fluorescence intensities as a function of the photon energy to the photoionization cross sections. The L x-ray intensities were corrected for solid-state effects which were estimated from the comparison of the measured and theoretical Pd L -edge x-ray-absorption spectra. Thanks to high resolution, the partial CK yield f13L1L3M could be extracted from the intensities of the resolved L?M satellite transitions. For f23 , f12 , and f13 CK rates, values of 0.164±0.033 , 0.047±0.001 , and 0.730±0.039 were found, respectively. For the partial CK yields f13L1L3M and f13L1L3N , results of 0.406±0.023 and 0.324±0.032 , respectively, were obtained.

  12. M sub-shell fluorescence and Coster-Kronig yield data generation for elements, 57?Z?90 (computer code ‘MFCKYLD')

    NASA Astrophysics Data System (ADS)

    Kaur, Gurpreet; Mittal, Raj

    2014-01-01

    M subshell fluorescence yield (?Mi, i=1-5) and Coster-Kronig yield (fMij, i=1-4, j=2-5) values have been generated for elements with Z, 57?Z?90. Keeping in view the importance of ?Mi and fMij for M X-ray productions in the region Z>56, the interpolation of non-relativistic data of McGuire [Phys. Rev. A 1972;5:1043-7] in the region Z=57-90 as well as relativistic data of Chen et al. [Phys. Rev. A 1980;21:449-53 and 1983;27:2989-94] in the region Z=67-90 was attempted. The agreement between the generated data and the actual ones supported the adopted procedure. Subsequently, a computer software code MFCKYLD was developed to generate the yield values on computer terminal or in file for both non-relativistic and relativistic data just by entering the atomic number Z of the element through keyboard or file. The precision of present procedure that relies on the deviation of fitted values from the actual ones was found far better than the earlier fitted data.

  13. Dirac-Fock calculations of K -, L -, and M -shell fluorescence and Coster-Kronig yields for Ne, Ar, Kr, Xe, Rn, and Uuo

    NASA Astrophysics Data System (ADS)

    Sampaio, J. M.; Madeira, T. I.; Guerra, M.; Parente, F.; Santos, J. P.; Indelicato, P.; Marques, J. P.

    2015-05-01

    In this work, we calculated the fluorescence and Coster-Kronig yields for the K shell and the L and M subshells of Ne, Ar, Kr, Xe, Rn, and Uuo (Z =118 ), using a Dirac-Fock model which provides a better description of the electron-electron interaction than previous approaches, and is suitable to handle superheavy elements. The results are compared with available data from other authors. In what concerns Ne, Ar, Kr, Xe, and Rn K shells, the obtained results are in very good agreement with the adopted values of Krause [25] and with experiment when available. For the L subshells, our results are in line with existing ones. For the M subshells and for all shells of Uuo there are no previous experimental and theoretical results to compare to our calculations.

  14. Relativistic radiationless transition probabilities for atomic K- and L-shells*1

    Microsoft Academic Search

    M. H. Chen; B. Crasemann; H. Mark

    1979-01-01

    Auger and Coster--Kronig transition probabilities have been calculated ab initio relativistically from perturbation theory, for frozen orbitals, in the Dirac--Hartree--Slater approach. Results in the j-j coupling scheme are tabulated for > or =22 elements with atomic numbers 18< or =Z< or =96.

  15. Atomic radiative and radiationless yields for K and L shells

    Microsoft Academic Search

    M. O. Krause

    1979-01-01

    The available body of information on (a) fluorescence, Auger, and Coster-Kronig yields, (b) radiative and radiationless transition rates, (c) level widths, (d) x-ray and Auger line widths, (e) x-ray and Auger spectra, and (f) Coster-Kronig energies has been used to generate an internally consistent set of values of atomic radiative and radiationless yields for the K shell (5 ?Z?110) and

  16. X-ray transitions in highly charged neonlike ions

    SciTech Connect

    Beiersdorfer, P.; von Gjoeler, S.; Bitter, M.; Hinnov, E.; Bell, R.; Bernabei, S.; Felt, J.; Hill, K.W.; Hulse, R.; Stevens, J.; Suckewer, S.; Timberlake, J.; Wouters, A.; Chen, M.H.; Scofield, J.H.; Dietrich, D.D.; Gerassimenko, M.; Silver, E.; Walling, R.S.; Hagelstein, P.L.

    1987-11-01

    Wavelength measurements of n=3 to n=2 transitions in neonlike Xe/sup 44 +/, La/sup 47 +/, Nd/sup 50 +/, and Eu/sup 53 +/ have been made using a high-resolution Bragg-crystal spectrometer on the Princeton Large Torus tokamak. The measurements cover the wavelength regions 2.00 to 3.00 (angstrom) and include the electric dipole, and the electric and magnetic quadrupole transitions. The measured wavelengths are compared to energy levels obtained from a multiconfigurational Dirac-Fock calculation. Systematic differences between the experimental and theoretical values are found, which vary smoothly with atomic number. The magnitude of the differences depends on the particular type of transition and ranges from -2.8 eV to +2.2 eV. Inclusion of electron correlation corrections due to ground state correlations and (super) Coster-Kronig type fluctuations in the theoretical energies is shown to reduce the differences for some but not all types of transitions.

  17. Average L-shell fluorescence, Auger, and electron yields

    Microsoft Academic Search

    M. O. Krause

    1980-01-01

    The dependence of the average L-shell fluorescence and Auger yields on the initial vacancy distribution is shown to be small. By contrast, the average electron yield pertaining to both Auger and Coster-Kronig transitions is shown to display a strong dependence. Numerical examples are given on the basis of Krause's evaluation of subshell radiative and radiationless yields. Average yields are calculated

  18. The Effect of an External Magnetic Field on L X-ray Intensity Ratios for Elements in the Range 73? Z? 92 at 59.54 keV

    NASA Astrophysics Data System (ADS)

    Demir, Demet; ?ahin, Yusuf

    2007-11-01

    The L shell x-ray intensity ratios L?/Ll, L?/L?, and L?/L? for Ta, W, Au, Hg, Tl, Pb, Bi, Th, and U have been measured using the 59.54 keV incident photon energy in the external magnetic field of intensities ± 0.15, ± 0.45, and ± 0.75 T. A comparison is made of the experimental values obtained for B=0 with calculated values using theoretical x-ray emission rates, subshell ionization cross sections, subshell fluorescence yields and Coster-Kronig transitions probabilities. In the absence of external magnetic field, a fairly agreement is observed between experimental and theoretical values.

  19. Effect of vacancy de-excitation parameters on L X-rays of Pb using H + beam

    NASA Astrophysics Data System (ADS)

    Jain, Arvind Kumar; Mohan, Harsh; Sharma, Sunita

    2010-06-01

    The collision progression including ionization of an inner-shell by an energetic proton and decay of vacancy is a motivating theme in ion-beam analysis. To explore measured vacancy de-excitation parameters for Pb, intensity ratios are experimentally determined from L X-rays with proton impact in the energy range 225-400 keV. Predictions of UAECPSSR theory are employed for ionization cross-sections. For atomic parameters such as transition rates, fluorescence, Auger and Coster-Kronig (CK) yields, various databases are used. In this paper, significance of these features and current progress are discussed.

  20. Transitions.

    ERIC Educational Resources Information Center

    Nathanson, Jeanne H., Ed.

    1993-01-01

    This theme issue on transitions for individuals with disabilities contains nine papers discussing transition programs and issues. "Transition Issues for the 1990s," by Michael J. Ward and William D. Halloran, discusses self-determination, school responsibility for transition, continued educational engagement of at-risk students, and service…

  1. Transitions.

    ERIC Educational Resources Information Center

    Field, David; And Others

    1992-01-01

    Includes four articles: "Career Aspirations" (Field); "Making the Transition to a New Curriculum" (Baker, Householder); "How about a 'Work to School' Transition?" (Glasberg); and "Technological Improvisation: Bringing CNC to Woodworking" (Charles, McDuffie). (SK)

  2. Au, Pb, Bi, and U M-subshell ionization by protons

    NASA Astrophysics Data System (ADS)

    de Castro Faria, N. V.; Freire, F. L., Jr.; de Pinho, A. G.; da Silveira, E. F.

    1983-11-01

    M-subshell ionization cross sections of Au, Pb, Bi, and U by proton bombardment were obtained over the projectile range 0.3-4.0 MeV. X rays were detected by Si(Li) spectroscopy. At least one characteristic radiative transition line for each M subshell was isolated and measured. Radiative and nonradiative branching ratios were taken from theoretical calculations of Bhalla and McGuire. Our total x-ray-production cross sections are compared with the measurements of other authors. Comparison of our scaled subshell ionization cross sections with calculations in the plane-wave Born approximation shows, in general, good agreement. Uncertainties in fluorescence yields and in super-Coster-Kronig coefficients can introduce great imprecision in some experimentally determined subshell ionization cross sections.

  3. Development of a coincidence system for the measurement of X-ray emission atomic parameters

    SciTech Connect

    Martinez, Filiberto; Miranda, Javier [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Apartado Postal 20-364, 01000 Mexico, D.F (Mexico)

    2013-07-03

    Preliminary results obtained in experiments carried out with an x-ray spectrometer built at the Instituto de Fisica for Atomic Physics and environmental sciences studies are presented. The experiments are based on a coincidence method for signals produced by LEGe and Si(Li) detectors. The x-ray fluorescence yields ({omega}{sub Li}) and Coster-Kronig transition probabilities (f{sub ij}) for elements with 55 {<=} Z {<=} 60 are among the quantities of interest. The method is based on the simultaneous detection of K x-rays with the LEGe detector and the L x-rays with the Si(Li) detector. The primary radiation source is an x-ray tube with Rh anode. The system was tested with the coincidence of the L x-rays from Ce with its K line, demonstrating the feasibility of the experiments.

  4. L X-ray intensity ratios for high Z elements induced with X-ray tube

    NASA Astrophysics Data System (ADS)

    Wang, Xing; Xu, Zhongfeng; Zhang, Limin

    2015-07-01

    We have studied the intensity ratios I(L?1,2)/I(L?1,2), I(L?1,2)/I(L?) and I(L?1,2)/I(L?) for elements Ta, W, Au and Pb by 13.1 keV bremsstrahlung radiation. In this work, experimental values were compared with the theoretical results and other experimental results. Theoretical results of the intensity ratios were calculated with theoretical subshell photoionization cross sections, fractional X-ray emission rates, fluorescence yields, and Coster-Kronig transition probabilities. Good agreement can be observed between experimental values and theoretical results. Comparing with L1 and L2 subshells, the ionization cross section of L3 subshell shows a large increase for Ta and W with the variation of excitation energy from 59.5 keV to 13.1 keV.

  5. Cascade decay of atomic magnesium after photoionization with a photoelectron-photoion coincidence method

    SciTech Connect

    Kanngiesser, B.; Malzer, W.; Mueller, M.; Schmidt, N.; Zimmermann, P.; Kochur, A. G.; Sukhorukov, V. L. [Institut fuer Atomare Physik und Lehrerbildung, Technische Universitaet Berlin, Hardenberstrasse 36, 10623 Berlin, (Germany); Rostov State University of Transport Communication, Rostov-na-Donu, 344038, Russia (Russian Federation)

    2003-08-01

    For the K-shell decay, magnesium is the first element in the periodic table which shows cascading transitions. We investigated the whole cascade of magnesium by using the photoelectron-photoion coincidence technique on the 1s, 2s, and 2p decay. The experimentally determined and calculated decay probabilities for the 1s{sup -1}, the 2s{sup -1}, and the 2p{sup -1} decay, i.e., the whole cascade, are in good agreement with each other. For the calculation of higher final ionic charge states, it was found that electron correlations have to be taken into account. The fluorescence yields for the K and L shell and the Coster-Kronig factor for the L shell were determined.

  6. L/M sub-shell measurements on INDUS-2 beam line BL16

    NASA Astrophysics Data System (ADS)

    Singla, Raj Mittal

    2015-06-01

    Beamline BL-16 on INDUS-2 at RRCAT, Indore has been employed for M sub shell measurements on Pt, Au, Hg, Pb, Th and U at 8 and 10 keV photon energies to determine M sub-shell X-ray emission cross-sections and for L sub-shell measurements on Dy, Ho, Er, Lu, Ta, W, Pt, Au, Hg, Pb and Bi with selective creation of electron vacancies in individual sub-shells to derive L Coster-Kronig (CK) yield values. The cross sections have been measured for the first time. The determined L sub-shell CK yields were used to explore some details of CK transitions.

  7. Calculation of Ion Charge State Distributions After Inner-Shell Ionization in Xe Atom

    SciTech Connect

    Mohammedein, Adel M.; Ghoneim, Adel A.; Kandil, Kandil M.; Kadad, Ibrahim M. [Applied Sciences Department, College of Technological Studies, P.O. Box 42325, Shuwaikh 70654 (Kuwait)

    2010-01-05

    The vacancy cascades following initial inner-shell vacancies in single and multi-ionized atoms often lead to highly charged residual ions. The inner-shell vacancy produced by ionization processes may decay by either a radiative or non-radiative transition. In addition to the vacancy filling processes, there is an electron shake off process due to the change of core potential of the atom. In the calculation of vacancy cascades, the radiative (x-ray) and non-radiative (Auger and Coster-Kronig) branching ratios give valuable information on the de-excitation dynamics of an atom with inner-shell vacancy. The production of multi-charged ions yield by the Auger cascades following inner shell ionization of an atom has been studied both experimentally and theoretically. Multi-charged Xe ions following de-excitation of K-, L{sub 1}-, L{sub 2,3}-, M{sub 1}-, M{sub 2,3}- and M{sub 4,5} subshell vacancies are calculated using Monte-Carlo algorithm to simulate the vacancy cascade development. Fluorescence yield (radiative) and Auger, Coster- Kronig yield (non- radiative) are evaluated. The decay of K hole state through radiative transitions is found to be more probable than non-radiative transitions in the first step of de-excitation. On the other hand, the decay of L, M vacancies through non-radiative transitions are more probable. The K shell ionization in Xe atom mainly yields Xe{sup 7+}, Xe{sup 8+}, Xe{sup 9+} and Xe{sup 10+} ions, and the charged X{sup 8+} ions are the highest. The main product from the L{sub 1}- shell ionization is found to be Xe{sup 8+}, Xe{sup 9+} ions, while the charged Xe{sup 8+} ions predominate at L{sub 2,3} hole states. The charged Xe{sup 6+}, Xe{sup 7+} and Xe{sup 8+} ions mainly yield from 3s{sub 1/2} and 3p{sub 1/2,3/2} ionization, while Xe in 3d{sub 3/2,5/2} hole states mainly turns into Xe{sup 4+} and Xe{sup 5+} ions. The present results are found to agree well with the experimental data.

  8. L -subshell vacancy decay processes for elements with 52?Z?57 following ionization using Mn K? x rays

    NASA Astrophysics Data System (ADS)

    Sharma, Veena; Kumar, Sanjeev; Mehta, D.; Singh, Nirmal

    2008-07-01

    The Li - (i=1-3) subshell x-ray spectra for the T52e , I53 , C55s , B56a , and L57a elements excited by Mn K? ( EK?2=5.888keV and EK?1=5.899keV ) x rays have been investigated using the F55e radioisotope in conjunction with a Cr absorber. A low-energy Ge detector was used to measure the L x rays at an emission angle ?=126° , where the second-order Legendre polynomial term P2 (cos?) associated with the angular distribution is annulled. In the case of the B56a and L57a elements, alignment of the L3 -subshell vacancy states was investigated through angular distribution measurements of the emitted L3 -subshell x rays. The L?1,2 and L?2,15 x-ray groups are observed to be nearly isotropic, while the data for the pure Ll (L3-M1) x-ray emission are indicative of a small anisotropic trend, though within experimental error. The integral x-ray fluorescence cross sections are deduced and interpreted in terms of Li -subshell photoionization cross sections, fluorescence and Coster-Kronig yields, and x-ray emission rates. The L2 -subshell x-ray cross sections for L57a measured using targets of lanthanum (III) fluoride and dilanthanum (III) trioxide are found to be unusually higher. The enhancement is observed due to the contribution of the L2 -subshell radiative resonant Raman scattering (RRS) of Mn K? x rays having energy around the L2 -subshell binding energy of L57a in these compounds. Also, the observed enhancement of the L3 -subshell x-ray cross sections in L57a is suggestive of intrashell vacancy transfer via L2-L3 Coster-Kronig RRS transitions. The L2 -subshell total RRS cross sections in L57a have been deduced from the present measured attenuation coefficients for Mn K? x rays in La2O3 and LaF3 . The L2 -subshell radiative and total RRS cross sections in L57a using LaF3 are higher by ˜30% than those using La2O3 . The contribution of processes predicted in the framework of Mozouchi’s four-band model involving inner subshells along with the valence and conduction bands of these wide-band-gap insulator compounds is likely to account for the observed results. The L2 -subshell radiative and L2-L3 Coster-Kronig yields and the ratio of the L2-M4 and L2-N4 radiative RRS intensities in both La compounds are found to be same and are consistent with values from photoexcited vacancy decay. The L2 -subshell radiative RRS was also observed to be isotropic.

  9. Photoionization measurements for the iron isonuclear sequence Fe{sup 3+}, Fe{sup 5+}, and Fe{sup 7+}

    SciTech Connect

    Gharaibeh, M. F.; Aguilar, A.; Covington, A. M.; Emmons, E. D.; Scully, S. W. J.; Phaneuf, R. A. [Department of Physics, University of Nevada, Reno, Nevada 89557-0220 (United States); Mueller, A. [Institut fuer Atom- und Molekuelphysik, Universitaet Giessen, D-35392 Giessen (Germany); Bozek, J. D.; Kilcoyne, A. L. D.; Schlachter, A. S. [Advanced Light Source, MS 7-100, Lawrence Berkeley National Laboratory Berkeley, California 94720 (United States); Alvarez, I.; Cisneros, C.; Hinojosa, G. [Centro de Ciencias Fisicas, Universidad Nacional Autonoma de Mexico, Apartado Postal 6-96, Cuernavaca 62131 (Mexico)

    2011-04-15

    Cross sections for single photoionization of Fe{sup 3+}, Fe{sup 5+}, and Fe{sup 7+} ions were measured at spectral resolutions of 0.04, 0.15, and 0.13 eV, respectively, by merging mass- and charge-selected ion beams with a beam of monochromatized synchrotron undulator radiation. The measurements span photon energy ranges beginning at the ionization thresholds and extending several tens of electron volts to include the most important resonant contributions due to 3p-nd transitions to autoionizing states. The photoion yield spectra are characterized by narrow resonances and also broad features in Fe{sup 3+} and Fe{sup 5+} that are believed to result from unresolved fast super-Coster-Kronig transitions following 3p-3d excitation. Absolute photoionization cross-section measurements were also performed using ion beams containing undetermined fractions of ions in their ground and metastable states. A Rydberg series attributed to 3p-nd transitions from the {sup 2}G{sub 1} metastable state in Fe{sup 3+} was identified. The data are compared with recently published measurements on Fe{sup 3+} and Fe{sup 5+} using a similar technique at lower spectral resolution.

  10. Double L3M ionization of Pd induced by impact with medium-energy electrons

    NASA Astrophysics Data System (ADS)

    Cao, W.; Dousse, J.-Cl.; Hoszowska, J.; Kav?i?, M.; Kayser, Y.; Schenker, J.-L.; Žitnik, M.

    2011-02-01

    The electron-induced L3M two-step double ionization cross sections of metallic Pd were determined experimentally for incident electron beam energies ranging from the double ionization threshold up to 18 keV. The double L3M ionization cross sections were derived from the intensity ratios (IL?M:IL?) of the resolved M satellites to the parent diagram lines. The sample was bombarded with monoenergetic electrons from an energy-tunable 20-kV electron gun. The diagram and M-satellite x-ray lines were measured by means of high-resolution x-ray spectroscopy, using a reflection-type von Hamos bent crystal spectrometer. The two-step partial cross sections were determined by subtracting from the measured total double ionization cross sections the contributions due to the shake process and L1-L3M4,5 Coster-Kronig transitions. Despite the thick target employed in the present study, the dependence of the two-step cross sections on the incoming electron energy could be derived using a target slice decomposition method. It is shown that the obtained energy dependence can be well reproduced by the semiempirical parametrization model of Pattard and Rost.

  11. A new fundamental parameter based calibration procedure for micro X-ray fluorescence spectrometers

    NASA Astrophysics Data System (ADS)

    Wolff, Timo; Malzer, Wolfgang; Mantouvalou, Ioanna; Hahn, Oliver; Kanngießer, Birgit

    2011-02-01

    Fundamental parameter based quantification of X-ray fluorescence (XRF) measurement data requires an accurate knowledge of the spectrometer parameters, including the spectral distribution of the excitation radiation. In case of micro-XRF where a polycapillary optic is utilized in the excitation channel this distribution is changed due to the transmission properties of the lens. A new calibration procedure, based on fluorescence data of thin standard samples, was developed to determine the excitation spectrum, i.e., the product of the X-ray tube spectrum and the transmission of the used X-ray optic of a micro-XRF setup. The calibration result was validated by the quantitative analyses of certified multi-element reference standards and shows uncertainties in the order of 2% for main components, 10% for minor elements and 25% for trace elements. The influence of secondary order effects like Coster-Kronig transitions and cascade effects is analyzed and the accuracy of fundamental parameters in common databases is discussed.

  12. Photon-induced L X-ray production differential cross sections in thorium at 22.6 keV

    NASA Astrophysics Data System (ADS)

    Puri, Sanjiv; Mehta, D.; Shahi, J. S.; Garg, M. L.; Singh, Nirmal; Trehan, P. N.

    1999-04-01

    The Ll, L?, L? 2,4, L? 1,3 and L? 1,5 X-ray production differential cross sections in 90Th have been measured at 22.6 keV incident photon energy in an angular range 50-130°. The measurements were performed using a 109Cd annular-source and a Si(Li) detector. The measured differential cross sections for various L X-rays are found to be angle-independent within experimental error. This is contrary to the strong angular-dependence of photon-induced Ll and L? X-ray production cross sections as reported by Kahlon et al. (K.S. Kahlon, H.S. Aulakh, N. Singh, R. Mittal, K.L. Allawadhi, B.S. Sood, Phys. Rev. A 43 (1991) 1455) and Ertugrul (M. Ertugrul, Nucl. Instr. and Meth. B 119 (1996) 345). Integral cross sections for production of Ll, L?, L?, L? 6, L? 2,4, L? 1,3, L? 9,10, L? 1,5 and total L? X-rays are also deduced and are found to be in good agreement with those calculated using reliable theoretical values of the L i ( i=1, 2, 3) subshell photoionisation cross sections, fluorescence yields, X-ray emission rates and Coster-Kronig transition probabilities.

  13. Computation of Ion Charge State Distributions After Inner-Shell Ionization In Ne, Ar And Kr Atoms Using Monte Carlo Simulation

    SciTech Connect

    Mohammedein, Adel M.; Ghoneim, Adel A.; Al-Zanki, Jasem M.; El-Essawy, Ashraf H. [Applied Sciences Department, College of Technological Studies, P.O. Box 42325, Shuwaikh 70654 (Kuwait)

    2010-01-05

    Atomic reorganization starts by filling the initially inner-shell vacancy by a radiative transition (x-ray) or by a non-radiative transition (Auger and Coster-Kronig processes). New vacancies created during this atomic reorganization may in turn be filled by further radiative and non-radiative transitions until all vacancies reach the outermost occupied shells. The production of inner-shell vacancy in an atom and the de-excitation decays through radiative and non-radiative transitions may result in a change of the atomic potential; this change leads to the emission of an additional electron in the continuum (electron shake-off processes). In the present work, the ion charge state distributions (CSD) and mean atomic charge ions produced from inner-shell vacancy de-excitation decay are calculated for neutral Ne, Ar and Kr atoms. The calculations are carried out using Monte Carlo (MC) technique to simulate the cascade development after primary vacancy production. The radiative and non-radiative transitions for each vacancy are calculated in the simulation. In addition, the change of transition energies and transition rates due to multi vacancies produced in the atomic configurations through the cascade development are considered in the present work. It is found that considering the electron shake--off process and closing of non-allowed non-radiative channels improves the results of both charge state distributions (CSD) and average charge state. To check the validity of the present calculations, the results obtained are compared with available theoretical and experimental data. The present results are found to agree well with the available theoretical and experimental values.

  14. LMM Auger primary excitation spectra of copper

    NASA Astrophysics Data System (ADS)

    Pauly, N.; Tougaard, S.; Yubero, F.

    2014-12-01

    The shape and intensity of measured Auger peaks are strongly affected by extrinsic excitations due to electron transport out of the surface and to intrinsic excitations induced by the sudden creation of the two static core holes. Following a method developed for XPS in a previous work [N. Pauly, S. Tougaard, F. Yubero, Surf. Sci. 620 (2014) 17], we have calculated the effective energy-differential inelastic electron scattering cross-sections, including the effects of the surface and of the two core holes, within the dielectric response theory by means of the QUEELS-XPS software (QUantitative analysis of Electron Energy Losses at Surfaces for XPS). The Auger spectra are then modeled by convoluting this energy loss cross section with the primary excitation spectrum that accounts for all effects which are part of the initial Auger process, i.e. L-S coupling and vacancy satellite effects. The shape of this primary excitation spectrum is fitted to get close agreement between the theoretical and the experimental spectra obtained from X-ray excited Auger electron spectroscopy (XAES). We have performed these calculations of XAES spectra for various LMM Auger transitions of pure Cu (L3M45M45, L3M23M45, L3M23M23 and L2M45M45 transitions). We compare the resulting primary excitation spectra with theoretical results published in the literature and obtain reasonable quantitative agreement. In particular, we extract from experimental spectra quantitative intensities due to Coster-Kronig, shake-off and shake-up processes relative to the intensity from the “normal” Auger process.

  15. Transit Tracks

    NSDL National Science Digital Library

    Lawrence Hall of Science

    2008-01-01

    In this space science activity, learners explore transits and the conditions when a transit may be seen. Learners use models to investigate how a planet's size and distance from its star affects the behavior of transits. Learners also use mathematics to interpret graphs of brightness vs. time to deduce information about planet-star systems. This lesson includes educator instructions, photocopy masters for Transit Light Curves, Option Math for Transit Tracks, Kepler’s 3rd Law graphs, cube root tables, an account of Jeremiah Horrocks' 1639 observation of the transit of Venus, and an answer key for the Transit Tracks Light Curves.

  16. The line shape of L2 - L2L3M4,5 - M4,5M4,5(M4,5) satellites in the auger spectra of solids

    NASA Astrophysics Data System (ADS)

    Cini, M.; Perfetto, E.; Stefanucci, G.; Ugenti, S.

    2008-03-01

    We propose the foundations of an extended Auger Line Shape Analysis aiming to include the Coster-Kronig (CK) satellites in solid state spectra. In many solids like Cu and Zn metals they show up as intense high binding energy satellites of the Core-Valence-Valence (CVV) lines. Our theory covers the whole range between weak and strong correlation. We find that the satellites display three-hole and distorted two-hole features along with uncorrelated band-like continua.

  17. Transition & Beyond

    MedlinePLUS

    ... Transition & Beyond Aging Matters Research NDSS en Español Finances Ways to Give Ways to Donate NDSS Your ... Bienestar Emocional y Psiquiátrico La Enfermedad de Alzheimer Finances SSI Special Needs Trusts e-newsletter signup New & ...

  18. Transition Resources

    NSDL National Science Digital Library

    Transition

    2011-11-23

    This is a site for teachers that work with students with disabilities at the secondary level. This site is broken down into categories to help you with the transition aspect of the IEP. The categories are as follows: Employment/Training, For Students - Career Exploration and Profiles, Independent Living, Learning Styles & Trainings, Level 1 Assessments, Self-Determination, and Transition Resources. All of the resources included in this site are free! TRANSITION RESOURCES: 1.) Adult Career and Continuing Education Services (ACCES-VR) This website takes you directly to the ACCES-VR website, where you can find information about vocational rehabilitation and the referral process. 2,) Guide to Quality Individualized Education Program (IEP) Development and Implementation Created by the New York State Special Education Department to help answer questions regarding the New IEP. Great resource! Gives examples!! 3.) Indicator 13 Checklist Use this ...

  19. Venus Transit

    NSDL National Science Digital Library

    2012-08-03

    This is an activity about the Venus Transit and how it helped astronomers determine the scale of the solar system. Learners will use measurement, ratios, and graphing to construct a model of the solar system and determine the relationship of each planet to the Sun. They will explore the scales needed to represent the size of the planets and the distances to the Sun. This activity corresponds to the NASA CONNECT video, titled Venus Transit, and has supplemental questions to support the video viewing.

  20. L{beta}1 and L{beta}2 Satellites in the X-ray Emission Spectra

    SciTech Connect

    Poonia, Surendra [Division of Natural Resources and Environment, Central Arid Zone Research Institute, Jodhpur - 342 003, Rajasthan (India)

    2005-10-26

    The X-ray satellites L{beta}{sub 1}{sup I}, L{beta}{sub 1}{sup II}, L{beta}{sub 1}{sup III}, L{beta}{sub 1}{sup IV}, L{beta}{sub 2}{sup I}, L{beta}{sub 2}{sup (b)}, L{beta}{sub 2}{sup II} and L{beta}{sub 2}{sup (c)} observed in the L-emission spectra in elements with Z = 26 to 92, have been calculated. The energies of various transitions have been calculated by available Hartree-Fock-Slater (HFS) data using the semi-empirical Auger transition energies in the doubly ionized atoms and their relative intensities have been estimated by considering cross - sections of singly ionized 2x-1 (x {identical_to} s, p) states and then of subsequent Coster-Kronig and shake off processes. The calculated spectra have been compared with the measured satellite energies in the L emission spectra. Their intense peaks have been identified as the observed satellite lines. The one to one correspondence between the peaks in calculated spectra and the satellites in measured spectra has been established on the basis of the agreement between the separations in the peak energies and those in the measured satellite energies. Group of transitions under the transition schemes L2Mx-MxM4,5 and L3Mx-MxN4,5 (x {identical_to} 1-5), which give rise to these satellites have been identified. It is observed that the satellite L{beta}{sub 2}{sup (b)} in all these spectra can be assigned to the superposition of 3F4-3G5 and 3F4-3D3 transitions and that this must be most intense one out of all these satellites, contributing in order of decreasing intensity. Each of the remaining satellites is found to have different origin in different elements. The possible contributions of the suitable transitions to all these lines have also been discussed.

  1. Glass Transition

    Microsoft Academic Search

    Fumiko Yonezawa; Shoichi Sakamoto; Shuichi Nosé

    1990-01-01

    Computer simulations of melting, crystallization, glass transition, and annealing for a model system of 864 Lennard-Jones (LJ) atoms under a periodic boundary condition are carried out using constant-pressure molec ular dynamics techniques with temperature control. When an fcc crystal of LJ atoms is heated, melting occurs; however, an LJ liquid, when quenched slowly, crystallizes into layers with stacking faults. Each

  2. Radioactive Transitions

    NSDL National Science Digital Library

    This resource provides an interactive activity demonstrating how radioactive transitions (photon absorption and stimulated emission) occur in an optical field. Many important phenomena are emergent behaviors of this dynamic model. An interactive diagram is presented allowing students to experiment and watch a simulation of the result.

  3. TRANSITION DE MOTT METAL-INSULATOR TRANSITIONS

    E-print Network

    Paris-Sud XI, Université de

    TRANSITION DE MOTT METAL-INSULATOR TRANSITIONS IN TRANSITION METAL OXIDES by D. B. McWHAN, A. MENTH with increasing number of d elec- trons in the transition metal oxides. In the (V1-~Cr~)203system a Mott predominantly non-trivalent ions favor the metallicstate. I. Introduction. -Transition metal oxides form a class

  4. Eliminating Transitions

    ERIC Educational Resources Information Center

    Gallick, Barb; Lee, Lisa

    2010-01-01

    Adults often find themselves transitioning from one activity to another in a short time span. Most of the time, they do not feel they have a lot of control over their schedules, but wish that they could carve out extended time to relax and focus on one project. Picture a group of children in the block area who have spent 15 or 20 minutes building…

  5. PyTransit: Transit light curve modeling

    NASA Astrophysics Data System (ADS)

    Parviainen, Hannu

    2015-05-01

    PyTransit implements optimized versions of the Giménez and Mandel & Agol transit models for exoplanet transit light-curves. The two models are implemented natively in Fortran with OpenMP parallelization, and are accessed by an object-oriented python interface. PyTransit facilitates the analysis of photometric time series of exoplanet transits consisting of hundreds of thousands of data points, and of multipassband transit light curves from spectrophotometric observations. It offers efficient model evaluation for multicolour observations and transmission spectroscopy, built-in supersampling to account for extended exposure times, and routines to calculate the projected planet-to-star distance for circular and eccentric orbits, transit durations, and more.

  6. Intracellular potassium: 40K as a primordial gene irradiator.

    PubMed Central

    Moore, F D; Sastry, K S

    1982-01-01

    We have been interested in the possibility that the low energy electrons (Auger and Coster-Kronig) emitted after the electron capture decay of 40K may have highly localized radiochemical effects on the genetic material--effects dependent upon the intracellular locus of potassium. We report here that these effects are such that the likelihood of mutagenesis by their impact on DNA is substantial. This suggests that intracellular 40K has played a significant role as a mutagenic agent in evolution. PMID:6954503

  7. Gas turbine combustor transition

    DOEpatents

    Coslow, Billy Joe (Winter Park, FL); Whidden, Graydon Lane (Great Blue, CT)

    1999-01-01

    A method of converting a steam cooled transition to an air cooled transition in a gas turbine having a compressor in fluid communication with a combustor, a turbine section in fluid communication with the combustor, the transition disposed in a combustor shell and having a cooling circuit connecting a steam outlet and a steam inlet and wherein hot gas flows from the combustor through the transition and to the turbine section, includes forming an air outlet in the transition in fluid communication with the cooling circuit and providing for an air inlet in the transition in fluid communication with the cooling circuit.

  8. Utah Transit Authority Creating a Model Transit

    E-print Network

    Illinois at Urbana-Champaign, University of

    ;Topics · UTA System · Safety Focus · Organization · "Hold Point" activation process · Pedestrian GradeUtah Transit Authority Creating a Model Transit Safety Organization Global Level Crossing Safety and Trespasser Prevention Symposium August 2014 Dave Goeres, PE Chief Safety Officer dgoeres@rideuta.com #12

  9. Conceptualizing Transitions to Adulthood

    ERIC Educational Resources Information Center

    Wyn, Johanna

    2014-01-01

    This chapter provides an overview of theories of the transition to young adulthood. It sets out the argument for conceptual renewal and discusses some implications of new patterns of transition for adult education.

  10. Tips for Transition

    E-print Network

    Kellems, Ryan Owen; Morningstar, Mary E.

    2010-01-01

    -based transition practices used by practitioners, reviewed them, and confirmed their category based on the five broad areas of Kohler's Taxonomy for Transition Planning including student-focused planning, interagency collaboration, and family involvement. The tips...

  11. Transition: Preschool to Kindergarten

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2007

    2007-01-01

    Transition is movement or change without interruption. It should be a smooth flow from one place or condition to another. While the transition plan for a student receiving special education services is designed to prepare him or her for life after high school, transition can start when a child enters preschool. The second of six distinct stages of…

  12. Transit asset condition reporting

    Microsoft Academic Search

    Brian McCollom; Stephen A. Berrang

    2011-01-01

    The purpose of this synthesis was to examine and document the current state of the practice in transit asset condition management. Transit asset management is defined here as a strategic planning process that supports informed capital investment planning and programming. It is said that “good” transit asset management can provide critical support in two key areas—establishing the level of need

  13. Transitivity of Preferences

    ERIC Educational Resources Information Center

    Regenwetter, Michel; Dana, Jason; Davis-Stober, Clintin P.

    2011-01-01

    Transitivity of preferences is a fundamental principle shared by most major contemporary rational, prescriptive, and descriptive models of decision making. To have transitive preferences, a person, group, or society that prefers choice option "x" to "y" and "y" to "z" must prefer "x" to "z". Any claim of empirical violations of transitivity by…

  14. Transition Metal Compounds

    NASA Astrophysics Data System (ADS)

    Khomskii, Daniel I.

    2014-10-01

    1. Localised and itinerant electrons in solids; 2. Isolated transition metal ions; 3. Transition metal ions in crystals; 4. Mott–Hubbard vc charge-transfer insulators; 5. Exchange interaction and magnetic structures; 6. Cooperative Jahn–Teller effect and orbital ordering; 7. Charge ordering in transition metal compounds; 8. Ferroelectrics, magnetoelectrics and multiferroics; 9. Doping of correlated systems and correlated metals; 10. Metal-insulator transitions; 11. Kondoeffect, mixed valence and heavy fermions; Appendix A. Some historical notes; Appendix B. A layman's guide to second quantization; Appendix C. Phase transitions and free energy expansion: Landau theory in a nutshell.

  15. Deforming geometric transitions

    NASA Astrophysics Data System (ADS)

    Rossi, Michele

    2015-04-01

    After a quick review of the wild structure of the complex moduli space of Calabi-Yau 3-folds and the role of geometric transitions in this context (the Calabi-Yau web) the concept of deformation equivalence for geometric transitions is introduced to understand the arrows of the Gross-Reid Calabi-Yau web as deformation-equivalence classes of geometric transitions. Then the focus will be on some results and suitable examples to understand under which conditions it is possible to get simple geometric transitions, which are almost the only well-understood geometric transitions both in mathematics and in physics.

  16. Predictability of Critical Transitions

    E-print Network

    Zhang, Xiaozhu; Hallerberg, Sarah

    2015-01-01

    Critical transitions in multistable systems have been discussed as models for a variety of phenomena ranging from the extinctions of species to socio-economic changes and climate transitions between ice-ages and warm-ages. From bifurcation theory we can expect certain critical transitions to be preceded by a decreased recovery from external perturbations. The consequences of this critical slowing down have been observed as an increase in variance and autocorrelation prior to the transition. However especially in the presence of noise it is not clear, whether these changes in observation variables are statistically relevant such that they could be used as indicators for critical transitions. In this contribution we investigate the predictability of critical transitions in conceptual models. We study the the quadratic integrate-and-fire model and the van der Pol model, under the influence of external noise. We focus especially on the statistical analysis of the success of predictions and the overall predictabil...

  17. Transition Region Models

    NASA Astrophysics Data System (ADS)

    Hansteen, V.; Murdin, P.

    2000-11-01

    The SOLAR TRANSITION REGION comprises the PLASMA between the CHROMOSPHERE and the CORONA. In both of these regions the temperature is fairly uniform. The transition region, by contrast, is believed to be characterized by a very steep temperature rise from a chromospheric temperature of slightly less than 104 K to coronal temperatures on the order of 106 K. The goal of modeling the transition regi...

  18. Semileptonic transition in QCD

    NASA Astrophysics Data System (ADS)

    Azizi, K.; Sundu, H.; ?ahin, S.

    2015-05-01

    We analyze the semileptonic transition, where or , within the standard model. We apply the QCD sum rule approach to calculate the transition form factors entering the low energy Hamiltonian defining this channel. The fit functions of the form factors are used to estimate the total decay widths and branching fractions in all lepton channels. The orders of the branching ratios indicate that this transition is accessible at LHCb in the near future.

  19. Metal-insulator transitions

    Microsoft Academic Search

    Masatoshi Imada; Atsushi Fujimori; Yoshinori Tokura

    1998-01-01

    Metal-insulator transitions are accompanied by huge resistivity changes, even over tens of orders of magnitude, and are widely observed in condensed-matter systems. This article presents the observations and current understanding of the metal-insulator transition with a pedagogical introduction to the subject. Especially important are the transitions driven by correlation effects associated with the electron-electron interaction. The insulating phase caused by

  20. Anomalous radiative transitions

    E-print Network

    Kenzo Ishikawa; Toshiki Tajima; Yutaka Tobita

    2014-09-30

    Anomalous transitions involving photons derived by many-body interaction of the form, $\\partial_{\\mu} G^{\\mu}$, in the standard model are studied. This does not affect the equation of motion in the bulk, but makes wave functions modified, and causes the unusual transition characterized by the time-independent probability. In the transition probability at a time-interval $T$ expressed generally in the form $P=T \\Gamma_0 +P^{(d)}$, now with $ P^{(d)} \

  1. Lb2 satellites spectra emitted due to N - shell spectator vacancy

    NASA Astrophysics Data System (ADS)

    Poonia, Surendra

    2003-05-01

    Lb2 satellites spectra emitted due to N - shell spectator vacancy SURENDRA POONIA Division of Natural Resources and Environment, Central Arid Zone Research Institute, Jodhpur - 342 003, Rajasthan, India Telephone No. +91-0291-514692, Fax No. +91-0291-745089 E - mail: asrao@cazri.raj.nic.in PACS No. 32.20Rj and 78.70E Key words: Lb2 satellites, N vacancy Lb2 transitions. ABSTRACT: The X-ray satellite spectra arising due to 2p3/2-14x-1-4x-14d-1 (x = s, p, d) transition array, in the elements Z = 40 to 92, have been calculated. While the energies of various transitions of the array have been determined by using available Hartree-Fock-Slater (HFS) data on 1s-1-2p-14x-1 and 2p-1-4x-14d-1 Auger transition energies and their relative intensities have been estimated by considering cross - sections of singly ionized 2x-1 (x = s, p) states and then of subsequent Coster-Kronig and shake off processes. The calculated spectra have been compared with the measured satellite energies in Lb2 spectra. Their intense peaks have been identified as the observed satellite lines. The one to one correspondence between the peaks in calculated spectra and the satellites in measured spectra has been established on the basis of the agreement between the separations in the peak energies and those in the measured satellite energies. It has been established that two satellites observed in the Lb2 region of the X-ray spectra of various elements and named b20 and b2(a) in order of increasing energy are mainly emitted by 2p-14d-1-4d-2 transitions. Considering the relative intensities of these transitions and the mutual closeness in their energies, the most intense one, namely the 3F4-3F4, and seven others of this array have been associated with the emission of the satellite b2(a), reported in the spectra of elements with Z < 60. In the range Z > 70, the second most intense transition, namely the 1D2-1D2, and a comparatively weaker transition, namely the 3D3-3P2 one, deviate from this group. Hence, only six transitions superpose to give rise to this satellite, which has been named as b20, in case of elements with Z > 70, in the literature. In the range Z > 65, this satellite gets an added intensity due to the superposition of some intense transitions 2p-14f-1-4d-14f-1 array. This superposition of two arrays in high Z elements justifies the name b20 different from b2(a), given to the analogously placed satellite in the spectra of lower Z elements. Finally, the four closely spaced satellites, reported in the b2 region of the spectrum 46Pd have been assigned to suitable 2p-14x-1-4x-14d-1 (x = s, p, d) transitions. REFERENCES: 1.Y. Cauchois and C. Senemaud, X-Ray wavelength Tables, 2nd ed., (Oxford: Pergamon) pp. 217-314, (1978). 2.S. N. Soni and M. H. Massoud, J. Phys. Chem. Solids 58(1), 145-151 (1997). 3.S. N. Soni and S. Poonia, J. Phys. Chem. Solids 61(9), 1509-1518 (2000). 4.S. Poonia and S. N. Soni, J. Phys. Chem. Solids 62(3), 503-511 (2001). 5.A. M. Vlaicu, T. Tochio, T. Ishizuka, D. Ohsawa, Y. Ito, T. Mukoyama, A. Nisawa, T. Shoji and S. Yoshikado, Phys. Rev. A 58(5), 3544-3551, (1998). 6.R. Diamant, S. Huotari, K. Hamalainen, R. Sharon, C. C. Kao and M. Deutsch, Phys. Rev. A 63(2), 2508-2513 (2001).

  2. TTVFast: Transit timing inversion

    NASA Astrophysics Data System (ADS)

    Deck, Katherine; Agol, Eric; Holman, Matt; Nesvorny, David

    2014-04-01

    TTVFast efficiently calculates transit times for n-planet systems and the corresponding radial velocities. The code uses a symplectic integrator with a Keplerian interpolator for the calculation of transit times (Nesvorny et al. 2013); it is available in both C and Fortran.

  3. Transitional Division Algorithms.

    ERIC Educational Resources Information Center

    Laing, Robert A.; Meyer, Ruth Ann

    1982-01-01

    A survey of general mathematics students whose teachers were taking an inservice workshop revealed that they had not yet mastered division. More direct introduction of the standard division algorithm is favored in elementary grades, with instruction of transitional processes curtailed. Weaknesses in transitional algorithms appear to outweigh…

  4. Transitions and Linkages.

    ERIC Educational Resources Information Center

    Ilfeld, Ellen M., Ed.; Hanssen, Elizabeth, Ed.

    1997-01-01

    If children are to benefit from a healthy, supportive early childhood experience, it is important to strengthen transitions between early childhood experiences in educational and care settings and the more formal educational system. This issue of Coordinator's Notebook focuses on strengthening linkages and transitions between home, preschool, and…

  5. Transition Coordinators: Define Yourselves.

    ERIC Educational Resources Information Center

    Asselin, Susan B.; Todd-Allen, Mary; deFur, Sharon

    1998-01-01

    Describes a technique that was used successfully to identify the changing roles and responsibilities of special educators as transition coordinators. The Developing a Curriculum (DACUM) model uses people who are currently working in the occupation to define job responsibilities. The duties of a transition coordinator are identified. (CR)

  6. Transitivity of preferences.

    PubMed

    Regenwetter, Michel; Dana, Jason; Davis-Stober, Clintin P

    2011-01-01

    Transitivity of preferences is a fundamental principle shared by most major contemporary rational, prescriptive, and descriptive models of decision making. To have transitive preferences, a person, group, or society that prefers choice option x to y and y to z must prefer x to z. Any claim of empirical violations of transitivity by individual decision makers requires evidence beyond a reasonable doubt. We discuss why unambiguous evidence is currently lacking and how to clarify the issue. In counterpoint to Tversky's (1969) seminal "Intransitivity of Preferences," we reconsider his data as well as those from more than 20 other studies of intransitive human or animal decision makers. We challenge the standard operationalizations of transitive preferences and discuss pervasive methodological problems in the collection, modeling, and analysis of relevant empirical data. For example, violations of weak stochastic transitivity do not imply violations of transitivity of preference. Building on past multidisciplinary work, we use parsimonious mixture models, where the space of permissible preference states is the family of (transitive) strict linear orders. We show that the data from many of the available studies designed to elicit intransitive choice are consistent with transitive preferences. PMID:21244185

  7. Trauma, Transitions, and Thriving

    Microsoft Academic Search

    David Hartman; Diane Zimberoff

    2005-01-01

    Transitional experiences, what happens between states when someone changes developmentally, are special windows of opportunity for growth. They can be viewed in the microcosm of one's moments or in the macrocosm of an individual's life. We explore varieties of transitions, such as incremental or abrupt (intentional\\/ revelatory), transcendent or immanent, the ecstatic \\

  8. Sudden gravitational transition

    Microsoft Academic Search

    Robert R. Caldwell; William Komp; Leonard Parker; Daniel A. T. Vanzella

    2006-01-01

    We investigate the properties of a cosmological scenario which undergoes a gravitational phase transition at late times. In this scenario, the Universe evolves according to general relativity in the standard, hot big bang picture until a redshift z < or approx. 1. Nonperturbative phenomena associated with a minimally-coupled scalar field catalyzes a transition, whereby an order parameter consisting of curvature

  9. Predictability of Critical Transitions

    E-print Network

    Xiaozhu Zhang; Christian Kuehn; Sarah Hallerberg

    2015-05-21

    Critical transitions in multistable systems have been discussed as models for a variety of phenomena ranging from the extinctions of species to socio-economic changes and climate transitions between ice-ages and warm-ages. From bifurcation theory we can expect certain critical transitions to be preceded by a decreased recovery from external perturbations. The consequences of this critical slowing down have been observed as an increase in variance and autocorrelation prior to the transition. However especially in the presence of noise it is not clear, whether these changes in observation variables are statistically relevant such that they could be used as indicators for critical transitions. In this contribution we investigate the predictability of critical transitions in conceptual models. We study the the quadratic integrate-and-fire model and the van der Pol model, under the influence of external noise. We focus especially on the statistical analysis of the success of predictions and the overall predictability of the system. The performance of different indicator variables turns out to be dependent on the specific model under study and the conditions of accessing it. Furthermore, we study the influence of the magnitude of transitions on the predictive performance.

  10. Accessibility-based transit planning

    E-print Network

    Busby, Jeffrey R

    2004-01-01

    A method for evaluating transit planning proposals using accessibility metrics is advanced in this research. A transit-accessibility model is developed intended for use by in-house transit agency planning staff as a ...

  11. Transiting Exoplanets with JWST

    E-print Network

    S. Seager; D. Deming; J. A. Valenti

    2008-08-13

    The era of exoplanet characterization is upon us. For a subset of exoplanets -- the transiting planets -- physical properties can be measured, including mass, radius, and atmosphere characteristics. Indeed, measuring the atmospheres of a further subset of transiting planets, the hot Jupiters, is now routine with the Spitzer Space Telescope. The James Webb Space Telescope (JWST) will continue Spitzer's legacy with its large mirror size and precise thermal stability. JWST is poised for the significant achievement of identifying habitable planets around bright M through G stars--rocky planets lacking extensive gas envelopes, with water vapor and signs of chemical disequilibrium in their atmospheres. Favorable transiting planet systems, are, however, anticipated to be rare and their atmosphere observations will require tens to hundreds of hours of JWST time per planet. We review what is known about the physical characteristics of transiting planets, summarize lessons learned from Spitzer high-contrast exoplanet measurements, and give several examples of potential JWST observations.

  12. Alternative fuel transit buses

    SciTech Connect

    Motta, R.; Norton, P.; Kelly, K. [and others

    1996-10-01

    The National Renewable Energy Laboratory (NREL) is a U.S. Department of Energy (DOE) national laboratory; this project was funded by DOE. One of NREL`s missions is to objectively evaluate the performance, emissions, and operating costs of alternative fuel vehicles so fleet managers can make informed decisions when purchasing them. Alternative fuels have made greater inroads into the transit bus market than into any other. Each year, the American Public Transit Association (APTA) surveys its members on their inventory and buying plans. The latest APTA data show that about 4% of the 50,000 transit buses in its survey run on an alternative fuel. Furthermore, 1 in 5 of the new transit buses that members have on order are alternative fuel buses. This program was designed to comprehensively and objectively evaluate the alternative fuels in use in the industry.

  13. The Postperovskite Transition

    SciTech Connect

    Shim, S.-H. (MIT)

    2008-07-15

    The discovery of the postperovskite (PPv) transition has profound impact on our understanding of the core-mantle boundary (CMB) region. Unlike perovskite (Pv), the PPv phase has a layered structure of the SiO6 octahedra, which may lead to a large contrast in some properties with Pv. Recent studies have proposed unusual properties of PPv, such as a large positive Clapeyron slope, a large sensitivity of the transition depth to iron, a decrease in bulk sound speed at the transition, and a development of significant lattice preferred orientation. Many of the proposed properties can provide explanations for the intriguing seismic observations at the CMB region. Yet significant discrepancies still exist. However, rapid developments in mineral physics will continue to improve our knowledge on the changes across the PPv transition.

  14. Oligocyclopentadienyl transition metal complexes

    SciTech Connect

    de Azevedo, Cristina G.; Vollhardt, K. Peter C.

    2002-01-18

    Synthesis, characterization, and reactivity studies of oligocyclopentadienyl transition metal complexes, namely those of fulvalene, tercyclopentadienyl, quatercyclopentadienyl, and pentacyclopentadienyl(cyclopentadienyl) are the subject of this account. Thermal-, photo-, and redox chemistries of homo- and heteropolynuclear complexes are described.

  15. Transitions in biofilm formation

    NASA Astrophysics Data System (ADS)

    Gordon, Vernita; Thatcher, Travis; Cooley, Benjamin

    2011-03-01

    Biofilms are multicellular, dynamic communities formed by interacting unicellular organisms bound to a surface. Forming a biofilm is a developmental process, characterized by sequential changes in gene expression and behavior as bacteria and yeast progress from discrete, free-swimming cells though stages that arrive at a mature biofilm. We are developing automated metrics to identify key transitions in early biofilm formation as cells attach to a surface, populate that surface, and adhere to each other to form early microcolonies. Our metrics use high-throughput tracking and analysis of microscopy movies to localize these transitions in space and time. Each of these transitions is associated with a loss of entropy in the bacterial system and, therefore, with biological activity that drives this loss of entropy. Better understanding of these transitions will allow automated determination of the strength and turn-on of attractive cell-surface and cell-cell interactions as biofilm development progresses.

  16. Transit & Arterial Performance

    E-print Network

    Bertini, Robert L.

    Transit & Arterial Performance Michael Wolfe & Mathew Berkow A Study of the Barbur Boulevard arterial performance in a corridor using both advance and system loop data · Ultimately, marry the two data

  17. Geomagnetic polarity transitions

    NASA Astrophysics Data System (ADS)

    Merrill, Ronald T.; McFadden, Phillip L.

    1999-05-01

    The top of Earth's liquid outer core is nearly 2900 km beneath Earth's surface, so we will never be able to observe it directly. This hot, dense, molten iron-rich body is continuously in motion and is the source of Earth's magnetic field. One of the most dynamic manifestations at Earth's surface of this fluid body is, perhaps, a reversal of the geomagnetic field. Unfortunately, the most recent polarity transition occurred at about 780 ka, so we have never observed a transition directly. It seems that a polarity transition spans many human lifetimes, so no human will ever witness the phenomenon in its entirety. Thus we are left with the tantalizing prospect that paleomagnetic records of polarity transitions may betray some of the secrets of the deep Earth. Certainly, if there are systematics in the reversal process and they can be documented, then this will reveal substantial information about the nature of the lowermost mantle and of the outer core. Despite their slowness on a human timescale, polarity transitions occur almost instantaneously on a geological timescale. This rapidity, together with limitations in the paleomagnetic recording process, prohibits a comprehensive description of any reversal transition both now and into the foreseeable future, which limits the questions that may at this stage be sensibly asked. The natural model for the geomagnetic field is a set of spherical harmonic components, and we are not able to obtain a reliable model for even the first few harmonic terms during a transition. Nevertheless, it is possible, in principle, to make statements about the harmonic character of a geomagnetic polarity transition without having a rigorous spherical harmonic description of one. For example, harmonic descriptions of recent geomagnetic polarity transitions that are purely zonal can be ruled out (a zonal harmonic does not change along a line of latitude). Gleaning information about transitions has proven to be difficult, but it does seem reasonable to draw the following conclusions with varying degrees of confidence. There appears to be a substantial decrease in the mean intensity of the dipole field during a transition to ˜25% of its usual value. The duration of an average geomagnetic polarity transition is not well known but probably lies between 1000 and 8000 years. Values outside these bounds have been reported, but we give reasons as to why such outliers are likely to be artifacts. The reversal process is probably longer than the manifestation of the reversal at Earth's surface as recorded in paleomagnetic directional data. Convection hiatus during a geomagnetic polarity transition seems unlikely, and free-decay models for reversals appear to be generally incompatible with the data. This implies that certain theorems in dynamo theory, such as Cowling's theorem, should not be invoked to explain the origin of reversals. Unfortunately, the detailed description of directional changes during transitions remains controversial. Contrary to common belief, certain low-degree nondipole fields can produce significant longitudinal confinement of virtual geomagnetic poles (VGP) during a transition. The data are currently inadequate to refute or verify claims of longitudinal dipole confinement, VGP clustering, or other systematics during polarity transitions.

  18. Transit of Venus

    NSDL National Science Digital Library

    The Transit of Venus is similar to a solar eclipse, where -- from the perspective on Earth -- Venus passes in front of the Sun. This event does not happen very often. In fact, no one alive today has experienced this phenomenon, which will take place on June 8 and will be visible for most of Europe, Asia, and Africa.First, the Armagh Planetarium created a great, expansive informational site all about the Transit of Venus (1). Users can find basic facts, observing information, histories of past transits, and much more. Next, the European Southern Observatory presents the VT-2004 project's aim to gain knowledge and encourage public interest in the event (2). Users can observe Venus's progression towards the transit with the daily images from April 17, 2004 to present news updates. Educators can discover transit-related activities and educational materials. The third site, created by NASA, discusses the details of the Sun-Earth Connection Education Forum and San Francisco's Exploratorium's live webcast of the Transit (3). The site supplies enjoyable, educational materials for students, educators, museums, scientists, and amateur astronomers. The next site, also created by NASA, provides an introduction to the Venus Transits that will take place June 2004 and 2012 (4). Visitors can find helpful figures and text about the geographic visibility of the events. The site offers an observer's handbook as well as a discussion about the predictions of the event. Next, Professor Backhaus presents a project where schools, amateur astronomers, and universities will collaborate to gather transit data and learn about observing (5). Users can discover the six parts of the project as well as learn how to participate in the worldwide endeavor. The sixth site also discusses a Venus Transit project (6). Endorsed by the Astronomical Association of Zurich, this project's goals are to process data collected by amateur astronomers by different observation methods, to act as a data exchange center, and to determine the astronomical unit. Next, the Exploratorium furnishes general information about the Transit, its history, how viewers observe it, what it looks like, and why it is an important event (7). Users can find out about the live webcast that will begin on June 7, 2004 from Athens, Greece. Educators can find student activities developed to integrate discussions into the classroom. Lastly, Willie Koorts, an employee at the South African Astronomical Observatory, recounts the observations of scientists in Africa of the last transit of Venus (8). The site contains many historical photographs along with informational diagrams and figures.

  19. Entrepreneurship in transitional economy

    Microsoft Academic Search

    Janusz K. Tanas; David B. Audretsch

    This paper explores the relationship among socio-political culture and the economic environment. It places the entrepreneur\\u000a at the forefront of the Transitional Economy and identifies the entrepreneur as a catalyst for change and progress. Within\\u000a wider world changes, this discussion and interrogation of entrepreneurial development in the Transitional Economy provides\\u000a new knowledge from the perspective of both the authors and

  20. Sudden gravitational transition

    Microsoft Academic Search

    Robert R. Caldwell; William Komp; Leonard Parker; Daniel A. T. Vanzella

    2006-01-01

    We investigate the properties of a cosmological scenario which undergoes a gravitational phase transition at late times. In this scenario, the Universe evolves according to general relativity in the standard, hot big bang picture until a redshift z≲1. Nonperturbative phenomena associated with a minimally-coupled scalar field catalyzes a transition, whereby an order parameter consisting of curvature quantities such as R2,

  1. Phase transitions in nuclear physics

    SciTech Connect

    Moretto, L.G.; Phair, L.; Wozniak, G.J.

    1997-08-01

    A critical overview of the low energy phase transitions in nuclei is presented with particular attention to the 2nd (1st) order pairing phase transitions, and to the 1st order liquid-vapor phase transition. The role of fluctuations in washing out these transitions is discussed and illustrated with examples. A robust indicator of phase coexistence in multifragmentation is presented.

  2. Examining hydrogen transitions.

    SciTech Connect

    Plotkin, S. E.; Energy Systems

    2007-03-01

    This report describes the results of an effort to identify key analytic issues associated with modeling a transition to hydrogen as a fuel for light duty vehicles, and using insights gained from this effort to suggest ways to improve ongoing modeling efforts. The study reported on here examined multiple hydrogen scenarios reported in the literature, identified modeling issues associated with those scenario analyses, and examined three DOE-sponsored hydrogen transition models in the context of those modeling issues. The three hydrogen transition models are HyTrans (contractor: Oak Ridge National Laboratory), MARKAL/DOE* (Brookhaven National Laboratory), and NEMS-H2 (OnLocation, Inc). The goals of these models are (1) to help DOE improve its R&D effort by identifying key technology and other roadblocks to a transition and testing its technical program goals to determine whether they are likely to lead to the market success of hydrogen technologies, (2) to evaluate alternative policies to promote a transition, and (3) to estimate the costs and benefits of alternative pathways to hydrogen development.

  3. Sudden gravitational transition

    NASA Astrophysics Data System (ADS)

    Caldwell, Robert R.; Komp, William; Parker, Leonard; Vanzella, Daniel A. T.

    2006-01-01

    We investigate the properties of a cosmological scenario which undergoes a gravitational phase transition at late times. In this scenario, the Universe evolves according to general relativity in the standard, hot big bang picture until a redshift z?1. Nonperturbative phenomena associated with a minimally-coupled scalar field catalyzes a transition, whereby an order parameter consisting of curvature quantities such as R2, RabRab, RabcdRabcd acquires a constant expectation value. The ensuing cosmic acceleration appears driven by a dark-energy component with an equation-of-state w<-1. We evaluate the constraints from type 1a supernovae, the cosmic microwave background, and other cosmological observations. We find that a range of models making a sharp transition to cosmic acceleration are consistent with observations.

  4. Venus Transit 2004

    NSDL National Science Digital Library

    In just several weeks, Venus, the Earth's sister planet, will pass in front of the sun, affording astronomers and the general public the ability to take part in a extremely rare event. While persons in Europe, Africa, and Asia will have the best vantage point for this occurrence, those interested in the Venus transit will want to take a detailed look at this lovely website in order to find out more about the event. Launched by the European Southern Observatory and the European Association for Astronomy Education (in cooperation with three other organizations), the site contains ample information about the latest news from the project, detailed background material about this astronomical event, the network of institutions involved with the project, and information on how individuals may participate in the Venus Transit 2004 project. One of the most helpful areas contains animations of the Venus transit from different perspectives.

  5. A Sudden Gravitational Transition

    E-print Network

    Caldwell, R R; Parker, L; Vanzella, D A T; Caldwell, Robert R.; Komp, William; Parker, Leonard; Vanzella, Daniel A. T.

    2006-01-01

    We investigate the properties of a cosmological scenario which undergoes a gravitational phase transition at late times. In this scenario, the Universe evolves according to general relativity in the standard, hot Big Bang picture until a redshift z \\lesssim 1. Non-perturbative phenomena associated with a minimally-coupled scalar field catalyzes a transition, whereby an order parameter consisting of curvature quantities such as R^2, R_{ab}R^{ab}, R_{abcd}R^{abcd} acquires a constant expectation value. The ensuing cosmic acceleration appears driven by a dark-energy component with an equation-of-state w type 1a supernovae, the cosmic microwave background, and other cosmological observations. We find that a range of models making a sharp transition to cosmic acceleration are consistent with observations.

  6. A Sudden Gravitational Transition

    E-print Network

    Robert R. Caldwell; William Komp; Leonard Parker; Daniel A. T. Vanzella

    2005-08-11

    We investigate the properties of a cosmological scenario which undergoes a gravitational phase transition at late times. In this scenario, the Universe evolves according to general relativity in the standard, hot Big Bang picture until a redshift z \\lesssim 1. Non-perturbative phenomena associated with a minimally-coupled scalar field catalyzes a transition, whereby an order parameter consisting of curvature quantities such as R^2, R_{ab}R^{ab}, R_{abcd}R^{abcd} acquires a constant expectation value. The ensuing cosmic acceleration appears driven by a dark-energy component with an equation-of-state w type 1a supernovae, the cosmic microwave background, and other cosmological observations. We find that a range of models making a sharp transition to cosmic acceleration are consistent with observations.

  7. Bottomonium dipion transitions

    SciTech Connect

    Simonov, Yu. A.; Veselov, A. I. [ITEP, Moscow (Russian Federation)

    2009-02-01

    Dipion transitions of the subthreshold bottomonium levels {upsilon}(nS){yields}{upsilon}(n{sup '}S){pi}{pi} with n>n{sup '}, n=2, 3, 4 n{sup '}=1, 2 are studied in the framework of the chiral decay Lagrangian, derived earlier. The channels BB, BB*+c.c., B*B* are considered in the intermediate state and realistic wave functions of {upsilon}(nS), B and B* are used in the overlap matrix elements. Imposing the Adler zero requirement on the transition matrix element, one obtains 2d and 1d dipion spectra in reasonable agreement with experiment.

  8. Viscosity near phase transitions

    E-print Network

    Antonio Dobado; Felipe J. Llanes-Estrada; Juan M. Torres-Rincon

    2010-09-30

    Probably the most enticing observation in theoretical physics during the last decade was the discovery of the great amount of consequences obtained from the AdS/CFT conjecture put forward by Maldacena. In this work we review how this correspondence can be used to address hydrodynamic properties such as the viscosity of some strongly interacting systems. We also employ the Boltzmann equation for those systems closer to low-energy QCD, and argue that this kind of transport coefficients can be related to phase transitions, in particular the QGP/hadronic phase transition studied in heavy ion collisions.

  9. Arizona's Universities in Transition.

    ERIC Educational Resources Information Center

    Caldwell, Roger L.

    One of the working papers in the final report of the Arizona Board of Regents' Task Force on Excellence, Efficiency and Competitiveness, this document presents statistical data on the transition of Arizona's universities, consolidating many ad hoc analyses. It lists selected data that helped identify and develop Task Force issues and describes the…

  10. Transit-bus maintenance

    SciTech Connect

    Purdy, J.E.; Wiegmann, J.D.; Maze, T.H.; Cook, A.R.; List, G.

    1987-01-01

    The 4 papers in the report deal with the following areas; vehicle maintenance: cost relationship and estimating methodology; theory and practice of transit-bus maintenance performance measurement; bus maintenance performance indicators; historical development and current practice; and terrain effects on bus-maintenance performance.

  11. TRANSITION STRATEGIES Sig Gronich

    E-print Network

    the transition phase and do not represent any specific policy recommendation. #12;3 Market Penetration Scenarios of thousands of vehicles per year. This option is expected to have a market penetration of 1.8 million HFCVs of HFCVs by 2018. Expected market penetration for this option is 3.4 million HFCVs by 2025. B. Early

  12. Women's Transitions in Retirement

    Microsoft Academic Search

    Diana Cort Van Arsdale; Phyllis Newman

    1993-01-01

    To facilitate insight into the choices and options each woman has for her retirement. the retirement olanner should guide each woman through a self ass~ssmenptr ocess. 'he first step invilves an examination of how she has cooed and made decisions during the other of life's transitions. This is 'followed by an assessment 07 the meaning work has for each individual:

  13. Learning for Life Transitions

    ERIC Educational Resources Information Center

    Varmecky, Jane Hyde

    2012-01-01

    Many adults return to formal learning situations to pursue lifelong learning goals because their lives are in transition from dealing with real-life problems such as divorce and re-marriage. The purpose of this study was to describe what couples learned that contributed to the success of their subsequent marriages and how they learned it. The…

  14. Mott Metal Insulator Transitions

    E-print Network

    Budker, Dmitry

    Physics Letters 95, no. 4 (2009) 14 #12;Mott Insulators: Actuators Bimorph Actuators Thermal Sensing Liu, despite being a "toy" model, is used in active research Crystal structures matter! Mott insulators haveMott Metal Insulator Transitions Satej Soman, Robert Tang-Kong March 21, Physics 141A 1 #12

  15. Immigration and Adult Transitions

    ERIC Educational Resources Information Center

    Rumbaut, Ruben G.; Komaie, Golnaz

    2010-01-01

    Almost 30 percent of the more than 68 million young adults aged eighteen to thirty-four in the United States today are either foreign born or of foreign parentage. As these newcomers make their transitions to adulthood, say Ruben Rumbaut and Golnaz Komaie, they differ significantly not only from one another but also from their native-parentage…

  16. The Anderson Transition

    Microsoft Academic Search

    Nevill Mott; M. Pepper; S. Pollitt; R. H. Wallis; C. J. Adkins

    1975-01-01

    An outline is given of the electrical properties expected in a disordered solid or fluid which shows a metal-insulator transition of Anderson type. This is one in which the Fermi energy of the electrons passes through a mobility edge separating extended states from states localized by disorder, as the composition or some other parameter is changed. Some of the experimental

  17. Structural Balance and Transitivity

    E-print Network

    Liu, Huan

    Structural Balance and Transitivity Social Network Analysis, Chapter 6 Wasserman and Faust #12;Balance Theory Concerned with how an individual's attitudes or opinions coincide with those of others in a network balance vs dissonance if two actors that are "friends" have the same "attitude" toward a third

  18. Transition Fault Simulation

    Microsoft Academic Search

    John Waicukauski; Eric Lindbloom; Barry Rosen; Vijay Iyengar

    1987-01-01

    Delay fault testing is becoming more important as VLSI chips become more complex. Components that are fragments of functions, such as those in gate-array designs, need a general model of a delay fault and a feasible method of generating test patterns and simulating the fault. The authors present such a model, called a transition fault, which when used with parallel-pattern,

  19. Transition radiation detectors

    Microsoft Academic Search

    Boris Dolgoshein

    1993-01-01

    The use of transition radiation (TR) as a means of identifying high energy particles has now become a subject of intensive experimental investigations and applications. Our intention is first to study the physics of these phenomena and to describe ways of building detectors which can efficiently identify particles.

  20. A Survey Transition Course

    ERIC Educational Resources Information Center

    Johnston, William; McAllister, Alex M.

    2012-01-01

    Successful outcomes for a "Transition Course in Mathematics" have resulted from two unique design features. The first is to run the course as a "survey course" in mathematics, introducing sophomore-level students to a broad set of mathematical fields. In this single mathematics course, undergraduates benefit from an introduction of proof…

  1. The TRANSITION Program.

    ERIC Educational Resources Information Center

    Office of the Assistant Secretary of Defense for Manpower and Reserve Affairs (DOD), Washington, DC.

    Operated on a voluntary, decentralized basis at 215 military bases (58 overseas), the TRANSITION Program is designed to provide maximum guidance and training or educational opportunities for servicemen during their last six months of duty to prepare them for productive reentry into civilian life. Public and private placement services are also…

  2. China's continuing urban transition

    Microsoft Academic Search

    Clifton W Pannell

    2002-01-01

    Urban growth in China has proceeded in step with the growth and transition of the socialist economy. Year 2000 Census data indicate an urban population of 456 million; this is 36% of the total population and is increasing much more rapidly than the overall population. Several factors drive this rapid urbanization and growth of cities and towns: continuing, although diminishing,

  3. Fluctuations at phase transitions

    E-print Network

    Rivers, R J

    1994-01-01

    We use the closed time-path formalism to calculate fluctuations at phase transitions, both in and out of equilibrium. Specifically, we consider the creation of vortices by fluctuations, of relevance to the early universe and to ^{4}He superfluidity. (Invited talk to Nato Advanced Research Workshop on Electroweak Physics and the Early Universe, Sintra (Portugal), March 1994)

  4. The transits of Venus

    Microsoft Academic Search

    A. Chapman

    1998-01-01

    The transits of Venus across the solar disk in 1761 and 1769 were two of the most momentous events in the history of astronomy. For, in the wake of Newton's theory of universal gravitation, the correct determination of the solar parallax (and the ensuing distance of the Sun) had become of the greatest significance in establishing the proportions of the

  5. Youth: Transition to Adulthood

    Microsoft Academic Search

    James S. Coleman

    1974-01-01

    Editor's Note. NASSP's interest in action-learn ing predated the appearance of Youth: Transition to Adulthood, the report of the Panel on Youth of the President's Science Advisory Committee, which was completed in the summer of 1973; but that report did much to fuel the fires of NASSP's interest, and it became a basic working document at Wingspread. Professor James S.

  6. Families in Transition .

    ERIC Educational Resources Information Center

    Bundy, Michael L., Ed.; Gumaer, James, Ed.

    1984-01-01

    Focuses on disrupted families and the role of the school counselor in helping children adjust. Describes characteristics of healthy families, and discusses the transition to the blended family, effects of divorce groups on children's classroom behavior, counseling children in stepfamilies, single-parent families, and parenting strengths of single…

  7. String mediated phase transitions

    NASA Technical Reports Server (NTRS)

    Copeland, ED; Haws, D.; Rivers, R.; Holbraad, S.

    1988-01-01

    It is demonstrated from first principles how the existence of string-like structures can cause a system to undergo a phase transition. In particular, the role of topologically stable cosmic string in the restoration of spontaneously broken symmetries is emphasized. How the thermodynamic properties of strings alter when stiffness and nearest neighbor string-string interactions are included is discussed.

  8. Water's second glass transition.

    PubMed

    Amann-Winkel, Katrin; Gainaru, Catalin; Handle, Philip H; Seidl, Markus; Nelson, Helge; Böhmer, Roland; Loerting, Thomas

    2013-10-29

    The glassy states of water are of common interest as the majority of H2O in space is in the glassy state and especially because a proper description of this phenomenon is considered to be the key to our understanding why liquid water shows exceptional properties, different from all other liquids. The occurrence of water's calorimetric glass transition of low-density amorphous ice at 136 K has been discussed controversially for many years because its calorimetric signature is very feeble. Here, we report that high-density amorphous ice at ambient pressure shows a distinct calorimetric glass transitions at 116 K and present evidence that this second glass transition involves liquid-like translational mobility of water molecules. This "double Tg scenario" is related to the coexistence of two liquid phases. The calorimetric signature of the second glass transition is much less feeble, with a heat capacity increase at Tg,2 about five times as large as at Tg,1. By using broadband-dielectric spectroscopy we resolve loss peaks yielding relaxation times near 100 s at 126 K for low-density amorphous ice and at 110 K for high-density amorphous ice as signatures of these two distinct glass transitions. Temperature-dependent dielectric data and heating-rate-dependent calorimetric data allow us to construct the relaxation map for the two distinct phases of water and to extract fragility indices m = 14 for the low-density and m = 20-25 for the high-density liquid. Thus, low-density liquid is classified as the strongest of all liquids known ("superstrong"), and also high-density liquid is classified as a strong liquid. PMID:24101518

  9. Transit of Extrasolar Planets

    NASA Technical Reports Server (NTRS)

    Doyle, Laurance R.

    1998-01-01

    During the past five years we have pursued the detection of extrasolar planets by the photometric transit method, i.e. the detection of a planet by watching for a drop in the brightness of the light as it crosses in front of a star. The planetary orbit must cross the line-of-sight and so most systems will not be lined up for such a transit to ever occur. However, we have looked at eclipsing binary systems which are already edge-on. Such systems must be very small in size as this makes the differential light change due to a transit much greater for a given planet size (the brightness difference will be proportional to the area of the transiting planet to the disc area of the star). Also, the planet forming region should be closer to the star as small stars are generally less luminous (that is, if the same thermal regime for planet formation applies as in the solar system). This led to studies of the habitable zone around other stars, as well. Finally, we discovered that our data could be used to detect giant planets without transits as we had been carefully timing the eclipses of the stars (using a GPS antenna for time) and this will drift by being offset by any giant planets orbiting around the system, as well. The best summary of our work may be to just summarize the 21 refereed papers produced during the time of this grant. This will be done is chronological order and in each section separately.

  10. Alternative fuel transit buses: The Pierce Transit Success Story

    SciTech Connect

    NONE

    1996-10-01

    The Pierce transit program for operating mass transit buses on compressed natural gas (CNG) is described. Cost, reliability, fuel efficiency, emission of combustion products, and future trends are discussed.

  11. Ion r-m transition lasers: possible transitions

    NASA Astrophysics Data System (ADS)

    Markova, S. V.; Petrash, Gueorgii G.

    1993-10-01

    An analysis of available transitions for pulsed laser oscillation from the first resonance levels to the metastable levels (r-m transitions) in singly ionized atoms is presented. The characteristics of resonance and metastable levels and wavelengths of corresponding r-m transitions are given for 30 elements. Energy level diagrams are presented for 8 typical elements.

  12. [Cancer and demographic transition].

    PubMed

    Napalkov, N P

    2004-01-01

    Two phenomena, one of which relates to the area of human reproduction and the other to the frequency, distribution, and control of disease in a population have emerged in the previous century and continue intensively to develop nowadays. Both these phenomena are directly related to the changes which are occurring in the incidence and prevalence of malignant tumours, as well as to mortality from them and to the opportunities for cancer control. The first of these phenomena has been denominated as the demographic, and the second as the epidemiological transition. The commonly accepted definition of the demographic transition is currently applied to designate a sustainable change in the type of population reproduction, when an initial and abrupt acceleration of population growth is replaced by its rapid deceleration with a subsequent stabilization of a population and a sharp change in its age structure. Demographic transition develops in a brief historical space of time and has the character of a global process. Population ageing and disequilibrium between the younger and older generations are the most important consequences of the demographic transition, and must inevitably influence the strategy and implementation of national cancer control programs. As life expectancy increases, so does the certainty that people will become more and more prone to diseases that are more common among older age groups, i.e. noncommunicable diseases and cancer in particular, rather than being affected by epidemics of infectious diseases. This situation is known as the epidemiological transition and reflects spectacular shifts in the pattern and causes of death and morbidity that have taken place in the vast majority of countries over the previous century. Epidemiological transition results in accession by poor countries to the problems of the rich, and leads to the "double burden" of disease in countries whose economies are undergoing transition, because of the still continuing burden of endemic infectious diseases. Russia is entering the final stages both of the demographic and the epidemiological transition, a period when numerous reasons, increasing demands on the systems of social protection and public health are inevitable. During the years 1992 to 2001, cancer incidence increased from 271.8 up to 313.9 per 100,000 population, i.e. a growth of over 16% and an annual rate of growth of 1.7%. According to the global estimates provided by the International Agency for Research on Cancer the number of new cancer cases in the year 2000 exceeded 10 million, and the number of deaths from cancer reached 6.2 million. The annual growth rate of global cancer incidence during the last 25-30 years was higher than the global population growth rate. Analysis of data available from population based cancer registries in Russia and abroad confirms the conclusion that cancer is mainly the fate of people belonging to the older age groups. Given the levels of exposure to specific carcinogens and genetic predisposition factors, the incidence of cancer should be considered as an exponential function of age. The unfeasibility of attempts to change, in the foreseeable future, the rate and trend of demographic transition and demographic ageing, in particular, is obvious. It would therefore be more feasible to envisage their probable consequences and to adapt the limited resources of national health and social support services to the needs of cancer control, which will significantly increase in the near future. PMID:15176213

  13. Calixarene supported transition metal clusters 

    E-print Network

    Taylor, Stephanie Merac

    2013-06-29

    This thesis describes a series of calix[n]arene polynuclear transition metal and lanthanide complexes. Calix[4]arenes possess lower-rim polyphenolic pockets that are ideal for the complexation of various transition metal ...

  14. Transition from Hospital to Home

    MedlinePLUS Videos and Cool Tools

    ... Injury 101 The Basics of Spinal Cord Injury Rehabilitation Preventing Pressure Sores Transition from Hospital to Home ... Cord Injury 101 The Basics of Pediatric SCI Rehabilitation Transitions for Children with Spinal Cord Injury What ...

  15. The transition to agricultural sustainability

    PubMed Central

    Ruttan, Vernon W.

    1999-01-01

    The transition to sustainable growth in agricultural production during the 21st century will take place within the context of a transition to a stable population and a possible transition to a stable level of material consumption. If the world fails to successfully navigate a transition to sustainable growth in agricultural production, the failure will be due more to a failure in the area of institutional innovation than to resource and environmental constraints. PMID:10339524

  16. Emergence and Phase Transitions

    NASA Astrophysics Data System (ADS)

    Sikkema, Arnold

    2006-05-01

    Phase transitions are well defined in physics through concepts such as spontaneous symmetry breaking, order parameter, entropy, and critical exponents. But emergence --- also exhibiting whole-part relations (such as top-down influence), unpredictability, and insensitivity to microscopic detail --- is a loosely-defined concept being used in many disciplines, particularly in psychology, biology, philosophy, as well as in physics[1,2]. I will review the concepts of emergence as used in the various fields and consider the extent to which the methods of phase transitions can clarify the usefulness of the concept of emergence both within the discipline of physics and beyond.1. Robert B. Laughlin, A Different Universe: Reinventing Physics from the Bottom Down (New York: Basic Books, 2005). 2. George F.R. Ellis, ``Physics and the Real World'', Physics Today, vol. 58, no. 7 (July 2005) pp. 49-54.

  17. Phase Transitions in Materials

    NASA Astrophysics Data System (ADS)

    Fultz, Brent

    2014-08-01

    Part I. Basic Thermodynamics and Kinetics of Phase Transformations: 1. Introduction; 2. Essentials of T-c phase diagrams; 3. Diffusion; 4. Nucleation; 5. Effects of diffusion and nucleation on phase transformations; Part II. The Atomic Origins of Thermodynamics and Kinetics: 6. Energy; 7. Entropy; 8. Pressure; 9. Atom movements with the vacancy mechanism; Part III. Types of Phase Transformations: 10. Melting; 11. Transformations involving precipitates and interfaces; 12. Spinodal decomposition; 13. Phase field theory; 14. Method of concentration waves and chemical ordering; 15. Diffusionless transformations; 16. Thermodynamics of nanomaterials; 17. Magnetic and electronic phase transitions; 18. Phase transitions in quantum materials; Part IV. Advanced Topics; 19. Low temperature analysis of phase boundaries; 20. Cooperative behavior near a critical temperature; 21. Elastic energy of solid precipitates; 22. Statistical kinetics of ordering transformations; 23. Diffusion, dissipation, and inelastic scattering; 24. Vibrational thermodynamics of materials at high temperatures.

  18. Transitions: exploring the frontier.

    PubMed

    Corless, Inge B

    End-of-life experiences go by various terms, including near-death experiences (NDEs), death bed visions, death bed phenomena, death bed coincidences, and nearing death awareness. Death bed escorts is the term applied to the vision of deceased family members or friends who inform the dying person that they will be accompanied in the transition from life. In this article, I examine the subject of NDEs and death bed escorts, starting with the rich body of work provided by Robert and Beatrice Kastenbaum. A subject of some interest to Robert Kastenbaum, he explored this frontier in his many writings on dying, death, and bereavement. Ever the pioneer and having made the ultimate transition, he may yet be exploring new frontiers. PMID:25351590

  19. Transition state in atomic physics

    Microsoft Academic Search

    Charles Jaffé; David Farrelly; T. Uzer

    1999-01-01

    The transition state is fundamental to modern theories of reaction dynamics: essentially, the transition state is a structure in phase space that all reactive trajectories must cross. While transition-state theory (TST) has been used mainly in chemical physics, it is possible to apply the theory to considerable advantage in any collision problem that involves some form of reaction. Of special

  20. DCCPS: BRP: PCRB: Care Transitions

    Cancer.gov

    PCRB is interested in research aimed at understanding and improving transitions between types of care along the cancer care continuum. Survivorship care planning interventions, patient navigation, teamwork, transitions coaching, and models such as the Patient-Centered Medical Home and shared care are contemporary examples of efforts to promote high quality transitional care within the US health system.

  1. The Community Vocational Transition Center.

    ERIC Educational Resources Information Center

    Botterbusch, Karl F.; Smith, Christopher A.

    This monograph outlines a model procedure for developing and running a community vocational transition center that would assist workers in making various planned and unplanned vocational transitions throughout their lives by offering a comprehensive array of vocational assessment and transition services. The first chapter addresses the question of…

  2. Stimulated coherent transition radiation

    SciTech Connect

    Hung-chi Lihn

    1996-03-01

    Coherent radiation emitted from a relativistic electron bunch consists of wavelengths longer than or comparable to the bunch length. The intensity of this radiation out-numbers that of its incoherent counterpart, which extends to wavelengths shorter than the bunch length, by a factor equal to the number of electrons in the bunch. In typical accelerators, this factor is about 8 to 11 orders of magnitude. The spectrum of the coherent radiation is determined by the Fourier transform of the electron bunch distribution and, therefore, contains information of the bunch distribution. Coherent transition radiation emitted from subpicosecond electron bunches at the Stanford SUNSHINE facility is observed in the far-infrared regime through a room-temperature pyroelectric bolometer and characterized through the electron bunch-length study. To measure the bunch length, a new frequency-resolved subpicosecond bunch-length measuring system is developed. This system uses a far-infrared Michelson interferometer to measure the spectrum of coherent transition radiation through optical autocorrelation with resolution far better than existing time-resolved methods. Hence, the radiation spectrum and the bunch length are deduced from the autocorrelation measurement. To study the stimulation of coherent transition radiation, a special cavity named BRAICER is invented. Far-infrared light pulses of coherent transition radiation emitted from electron bunches are delayed and circulated in the cavity to coincide with subsequent incoming electron bunches. This coincidence of light pulses with electron bunches enables the light to do work on electrons, and thus stimulates more radiated energy. The possibilities of extending the bunch-length measuring system to measure the three-dimensional bunch distribution and making the BRAICER cavity a broadband, high-intensity, coherent, far-infrared light source are also discussed.

  3. Kondo-Anderson transitions

    NASA Astrophysics Data System (ADS)

    Kettemann, S.; Mucciolo, E. R.; Varga, I.; Slevin, K.

    2012-03-01

    Dilute magnetic impurities in a disordered Fermi liquid are considered close to the Anderson metal-insulator transition (AMIT). Critical power-law correlations between electron wave functions at different energies in the vicinity of the AMIT result in the formation of pseudogaps of the local density of states. Magnetic impurities can remain unscreened at such sites. We determine the density of the resulting free magnetic moments in the zero-temperature limit. While it is finite on the insulating side of the AMIT, it vanishes at the AMIT, and decays with a power law as function of the distance to the AMIT. Since the fluctuating spins of these free magnetic moments break the time-reversal symmetry of the conduction electrons, we find a shift of the AMIT, and the appearance of a semimetal phase. The distribution function of the Kondo temperature TK is derived at the AMIT, in the metallic phase, and in the insulator phase. This allows us to find the quantum phase diagram in an external magnetic field B and at finite temperature T. We calculate the resulting magnetic susceptibility, the specific heat, and the spin relaxation rate as a function of temperature. We find a phase diagram with finite-temperature transitions among insulator, critical semimetal, and metal phases. These new types of phase transitions are caused by the interplay between Kondo screening and Anderson localization, with the latter being shifted by the appearance of the temperature-dependent spin-flip scattering rate. Accordingly, we name them Kondo-Anderson transitions.

  4. Transition Region Flows

    NASA Astrophysics Data System (ADS)

    Brekke, P.; Murdin, P.

    2000-11-01

    Ultraviolet emission lines emitted from the SOLAR TRANSITION REGION are often shifted from their expected rest wavelengths. Shifts of spectral lines are due to the so-called DOPPLER EFFECT, where the source of emission is moving either away from or towards the observer, causing a change in the apparent wavelength. The shifted emission lines are most often interpreted as a flow of plasma along ...

  5. High speed transition prediction

    NASA Technical Reports Server (NTRS)

    Gasperas, Gediminis

    1992-01-01

    The main objective of this work period was to develop, acquire and apply state-of-the-art tools for the prediction of transition at high speeds at NASA Ames. Although various stability codes as well as basic state codes were acquired, the development of a new Parabolized Stability Equation (PSE) code was minimal. The time that was initially allocated for development was used on other tasks, in particular for the Leading Edge Suction problem, in acquiring proficiency in various graphics tools, and in applying these tools to evaluate various Navier-Stokes and Euler solutions. The second objective of this work period was to attend the Transition and Turbulence Workshop at NASA Langley in July and August, 1991. A report on the Workshop follows. From July 8, 1991 to August 2, 1991, the author participated in the Transition and Turbulence Workshop at NASA Langley. For purposes of interest here, analysis can be said to consist of solving simplified governing equations by various analytical methods, such as asymptotic methods, or by use of very meager computer resources. From the composition of the various groups at the Workshop, it can be seen that analytical methods are generally more popular in Great Britain than they are in the U.S., possibly due to historical factors and the lack of computer resources. Experimenters at the Workshop were mostly concerned with subsonic flows, and a number of demonstrations were provided, among which were a hot-wire experiment to probe the boundary layer on a rotating disc, a hot-wire rake to map a free shear layer behind a cylinder, and the use of heating strips on a flat plate to control instability waves and consequent transition. A highpoint of the demonstrations was the opportunity to observe the rather noisy 'quiet' supersonic pilot tunnel in operation.

  6. The transition to marriage

    Microsoft Academic Search

    Mark R. Rank

    1981-01-01

    Cohabitation has often been viewed as easing the transition to marriage. The question is therefore asked, what characterizes relationships in which couples live together for an extended period of time prior to marriage, then decide to marry, and within two to three years are divorced? Four groups were interviewed (cohabitated\\/married; cohabitated\\/married\\/divorced; dated\\/married; dated\\/married\\/divorced) with the hope of analyzing the differences

  7. NASA metric transition plan

    NASA Astrophysics Data System (ADS)

    NASA science publications have used the metric system of measurement since 1970. Although NASA has maintained a metric use policy since 1979, practical constraints have restricted actual use of metric units. In 1988, an amendment to the Metric Conversion Act of 1975 required the Federal Government to adopt the metric system except where impractical. In response to Public Law 100-418 and Executive Order 12770, NASA revised its metric use policy and developed this Metric Transition Plan. NASA's goal is to use the metric system for program development and functional support activities to the greatest practical extent by the end of 1995. The introduction of the metric system into new flight programs will determine the pace of the metric transition. Transition of institutional capabilities and support functions will be phased to enable use of the metric system in flight program development and operations. Externally oriented elements of this plan will introduce and actively support use of the metric system in education, public information, and small business programs. The plan also establishes a procedure for evaluating and approving waivers and exceptions to the required use of the metric system for new programs. Coordination with other Federal agencies and departments (through the Interagency Council on Metric Policy) and industry (directly and through professional societies and interest groups) will identify sources of external support and minimize duplication of effort.

  8. Transition mixing study

    NASA Technical Reports Server (NTRS)

    Reynolds, R.; White, C.

    1986-01-01

    A computer model capable of analyzing the flow field in the transition liner of small gas turbine engines is developed. A FORTRAN code has been assembled from existing codes and physical submodels and used to predict the flow in several test geometries which contain characteristics similar to transition liners, and for which experimental data was available. Comparisons between the predictions and measurements indicate that the code produces qualitative results but that the turbulence models, both K-E and algebraic Reynolds Stress, underestimate the cross-stream diffusion. The code has also been used to perform a numerical experiment to examine the effect of a variety of parameters on the mixing process in transition liners. Comparisons illustrate that geometries with significant curvature show a drift of the jet trajectory toward the convex wall and weaker wake region vortices and decreased penetration for jets located on the convex wall of the liner, when compared to jets located on concave walls. Also shown were the approximate equivalency of angled slots and round holes and a technique by which jet mixing correlations developed for rectangular channels can be used for can geometries.

  9. Planetary transit surveys

    NASA Astrophysics Data System (ADS)

    Horne, K.

    2002-01-01

    I review the status and prospects of ground-based planetary transit surveys in the era before the Eddington and Kepler missions. Over 70 extra-solar planets have been found to date by high precision radial velocity searches, but so far only one of these exhibits planetary transits. This situation should dramatically reverse in the next few years as photometric searches begin to find large numbers of "Hot Jupiters" that transit in front of their host stars. I discuss and illustrate the methods being used to assess the planet catch of the Eddington mission. Scaling laws are derived to express the planet catch in terms of instrument parameters and planet type. More detailed Monte Carlo simulations yield simulated planet catalogs. Eddington's survey volume for Earth-analog planets extends to d ? 300 pc, and scales with star mass, planet radius and temperature as M-1/8r2T, strongly favouring large hot planets. The Eddington baseline design is likely to deliver only a handful of habitable Earths. The planet catch can be increased by design changes, subject of course to cost and feasibility constraints, to maximize the figure of merit ?d3 ~ ?(N At)3/2, where N is the number of co-aligned telescopes, A and ? are the effective pupil area and solid angle of each telescope, and t is the duration of the mission.

  10. Understanding the nutrition transition.

    PubMed

    Popkin, B M

    1996-09-01

    This article presents an overview of nutrition transition and experiences in China and Russia with monitoring of economic and health changes. Fogel (1994) showed that improvements in nutrition were associated with significant shifts in economic productivity. Over the past 300 years, the pace of dietary change has increased to some extent worldwide. Dietary changes are evident in changes in average stature and body composition and parallel major changes in health status. The nutrition transition follows the pattern of collecting food, famine, receding famine, degenerative disease, and behavioral change. The author's first proposition is that nutritional trends and dietary change are associated with population growth, age structure, and spatial distribution. Urban population has a distinctly different diet from rural population. Urban diets include superior grains, more milled and polished grains, higher fat content, more animal products, more sugar, and more prepared and processed food. Urban and rural diets are farther apart in low-income countries. The author's second proposition is that diet and activity are affected by income, patterns of work, and socioeconomic changes. Women's role changes affect household food preparation. Income allows for the purchase of goods or services that affect diet. Income increases are related to greater expenditures on food. The third proposition is that diet changes are associated with changes in knowledge and access to mass media. The last proposition is that interaction between epidemiological, socioeconomic, and demographic changes determines the nature and pace of nutrition transition. PMID:12178476

  11. Transition Mathematics Project

    NSDL National Science Digital Library

    The Transitions Math Project (TMP) aims to transition students in high school math to college-level math, without having to take remedial level math courses once they get to college. According to their site, "Twenty-two percent of college freshman need a remedial course in mathematics. In 2- year colleges the problem is even more acute." Visitors will learn in the "History" section of the "About TMP" link that since 2004, TMP has instituted three ways to help students improve their transition. First, they make clear expectations of teachers on what they must teach to prepare students for college-level math. Second, they inform parents and students what will be expected in college-level math, and finally, they establish networks between college and high school teachers to share teaching successes, techniques, and best practices. Visitors will find that the "Curriculum and Instructional Materials" section is a useful repository of curriculum and instructional resources created by TMP teams for use by all teachers. The site also provides professional development materials, TMP Resource Center, and links to their newsletter, math education news, and TMP's social media presence.

  12. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Preliminary Evaluation Results

    SciTech Connect

    Chandler, K.; Eudy, L.

    2007-03-01

    This report provides an evaluation of three prototype fuel cell-powered transit buses operating at AC Transit in Oakland, California, and six baseline diesel buses similar in design to the fuel cell buses.

  13. Pivotal Transitions - Historical and Today

    NASA Astrophysics Data System (ADS)

    Hurley, M.

    2008-08-01

    The goal of this paper is to enable readers to better "design" successful transitions that move Science and Technology or Research and Development (S&T/R&D) technologies and systems into operational capabilities for users. Transitions from S&T/R&D into acquisition and operations are challenging and critical to providing capab ilities to end users. Two historical examples, the Global Positioning System (GPS) and the Disaster Monitoring Constellation (DMC), are explored. Two current examples are also explored, including one from Operationally Responsive Space (ORS) which is in th e early stages of transition. While transitions are necessary, transition periods are inherently challenging and dynamically changing situations. These situations must be carefully managed and led in order to succeed. Characteristics, approaches, and incentives that foster effective transitions are discussed. Understanding the transition process and the communities involved allows one to maximize the chance of successfully moving an S&T/R&D development into an operational capability supporting end users.

  14. Evaluation of traffic signal controller transition methods

    E-print Network

    Hamilton, Curtis Lloyd

    2000-01-01

    methods in an Eagle EPAC300 series Controller unit were evaluated. The three transition methods tested were a Shortway Transition method, Shortway Add Only Transition method, and Infinite Dwell Transition method. The goal was to develop a methodology...

  15. Transition in Turbine Flows

    NASA Technical Reports Server (NTRS)

    Herbert, Thorwald

    1998-01-01

    We have further developed our capabilities to analyze transition in turbine boundary layers from first principles by integrating the nonlinear parabolized stability equations (PSE) with improved initial and boundary conditions. With modified iteration schemes, we are able to proceed deeper into the transition region where skin friction coefficient and heat transfer coefficient significantly increase. Initial and boundary conditions at elevated turbulence levels can be derived by receptivity analysis. Test runs for ERCOFTAC test case T3A at 2.4\\% turbulence level provide results in good agreement with the experimental data. The sharper minimum of the skin coefficient also shown by DNS results is likely due to the missing intermittency. The method has been applied to various experimentally studied turbine blades (UTRC, VKI, Zierke, Langston, Hippensteele, and others). The PSE results, though physically reasonable, do not agree as well as expected with the experimental findings. We have, therefore, performed an extensive search for the reasons of the seemingly systematic deviations. A first source of uncertainty has been found in the often insufficient documentation of the experiments (e.g. on blockage by end-wall boundary layers). However, variation of the relevant parameters does not lead to more satisfactory agreement. A second reason has been found in the "standard procedure" which considers a 2D flow at midspan and uses a panel code and subsequent boundary-layer code to obtain the laminar basic flow for the transition analysis. Comparison with the pressure distribution obtained with a 3D design code (RVC3D) shows significant three-dimensionality of the flow (e.g. in the UTRC experiments). The spanwise variation has been neglected in our original PSE code. To overcome this problem, we have developed the PSE/3D for fully 3D boundary layers to account for streamwise and spanwise variations. Since the design code does not provide the boundary-layer flow with sufficient resolution, we have generated the Euler solution and employed a 3D boundary-layer code to obtain the viscous basic flow. Although only the linear stability level of PSE/3D has been implemented so far, the discrepancies with the experiments change but do not disappear. We still find deviations between the computed and experimental variations of C(sub f), and St along the blade for laminar flow. The main reason can be seen by comparing the solution of the boundary-layer code with the viscous results of the design code. The conventional boundary-layer solution exhibits an asymptotic behavior appropriate in external aerodynamics but does not match the steep gradients of the inviscid flow through the passage and consequently provides biased results for C(sub f), and St. An attempt is currently being made to correct this deficiency. Before attempting to perform the transition analysis for the viscous flow provided by the design code, we have analyzed the implementation and "best possible" results. Code and results exhibit flaws that may negatively affect the design and are intolerable for transition analysis. Therefore, we have decided to develop a new code to obtain a reliable basis for stability and transition studies. We expect to report improved results by the time of the meeting.

  16. Semiconducting transition metal oxides

    NASA Astrophysics Data System (ADS)

    Lany, Stephan

    2015-07-01

    Open shell transition metal oxides are usually described as Mott or charge transfer insulators, which are often viewed as being disparate from semiconductors. Based on the premise that the presence of a correlated gap and semiconductivity are not mutually exclusive, this work reviews electronic structure calculations on the binary 3d oxides, so to distill trends and design principles for semiconducting transition metal oxides. This class of materials possesses the potential for discovery, design, and development of novel functional semiconducting compounds, e.g. for energy applications. In order to place the 3d orbitals and the sp bands into an integrated picture, band structure calculations should treat both contributions on the same footing and, at the same time, account fully for electron correlation in the 3d shell. Fundamentally, this is a rather daunting task for electronic structure calculations, but quasi-particle energy calculations in GW approximation offer a viable approach for band structure predictions in these materials. Compared to conventional semiconductors, the inherent multivalent nature of transition metal cations is more likely to cause undesirable localization of electron or hole carriers. Therefore, a quantitative prediction of the carrier self-trapping energy is essential for the assessing the semiconducting properties and to determine whether the transport mechanism is a band-like large-polaron conduction or a small-polaron hopping conduction. An overview is given for the binary 3d oxides on how the hybridization between the 3d crystal field symmetries with the O-p orbitals of the ligands affects the effective masses and the likelihood of electron and hole self-trapping, identifying those situations where small masses and band-like conduction are more likely to be expected. The review concludes with an illustration of the implications of the increased electronic complexity of transition metal cations on the defect physics and doping, using as an example the diversity of possible atomic and magnetic configurations of the O vacancy in TiO2, and the high levels of hole doping in Co2ZnO4 due to a self-doping mechanism that originates from the multivalence of Co.

  17. Semiconducting transition metal oxides.

    PubMed

    Lany, Stephan

    2015-07-22

    Open shell transition metal oxides are usually described as Mott or charge transfer insulators, which are often viewed as being disparate from semiconductors. Based on the premise that the presence of a correlated gap and semiconductivity are not mutually exclusive, this work reviews electronic structure calculations on the binary 3d oxides, so to distill trends and design principles for semiconducting transition metal oxides. This class of materials possesses the potential for discovery, design, and development of novel functional semiconducting compounds, e.g. for energy applications. In order to place the 3d orbitals and the sp bands into an integrated picture, band structure calculations should treat both contributions on the same footing and, at the same time, account fully for electron correlation in the 3d shell. Fundamentally, this is a rather daunting task for electronic structure calculations, but quasi-particle energy calculations in GW approximation offer a viable approach for band structure predictions in these materials. Compared to conventional semiconductors, the inherent multivalent nature of transition metal cations is more likely to cause undesirable localization of electron or hole carriers. Therefore, a quantitative prediction of the carrier self-trapping energy is essential for the assessing the semiconducting properties and to determine whether the transport mechanism is a band-like large-polaron conduction or a small-polaron hopping conduction. An overview is given for the binary 3d oxides on how the hybridization between the 3d crystal field symmetries with the O-p orbitals of the ligands affects the effective masses and the likelihood of electron and hole self-trapping, identifying those situations where small masses and band-like conduction are more likely to be expected. The review concludes with an illustration of the implications of the increased electronic complexity of transition metal cations on the defect physics and doping, using as an example the diversity of possible atomic and magnetic configurations of the O vacancy in TiO2, and the high levels of hole doping in Co2ZnO4 due to a self-doping mechanism that originates from the multivalence of Co. PMID:26126022

  18. Transition Metal Switchable Mirror

    SciTech Connect

    2009-08-21

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft.

  19. Transition Metal Switchable Mirror

    SciTech Connect

    None

    2009-01-01

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft. More information at: http://windows.lbl.gov/materials/chromogenics/default.htm

  20. ALICE Transition Radiation Detector

    E-print Network

    Pachmayer, Y

    2013-01-01

    The Transition Radiation Detector (TRD) is the main electron detector in ALICE. In conduction with the TPC and the ITS, it provides the necessary electron identification capability to study: - Production of light and heavy vector mesons as well as the continuum in the di-electron channel, - Semi leptonic decays of hadrons with open charm and open beauty via the single-electron channel using the displaced vertex information provided by the ITS, - Correlated DD and BB pairs via coincidences of electrons in the central barrel and muons in the forward muon arm, - Jets with high P? tracks in one single TRD stack.

  1. Superradiance Transition in Graphene

    E-print Network

    Alexander I. Nesterov; Fermín Aceves de la Cruz; Valeriy A. Luchnikov; Gennady P. Berman

    2015-06-12

    We study theoretically and numerically the conditions required for the appearance of a superradiance transition in graphene. The electron properties of graphene are described in the single $p_z$-orbital tight-binding approximation, in which the model is reduced to the effective two-level pseudo-spin $1/2$ system. For each level we introduce the electron transfer rate of escape into a continuum. We demonstrate that, under some conditions, the superradiance experiences the maximal quantum coherent escape to the continuum.

  2. Superradiance Transition in Graphene

    E-print Network

    Alexander I. Nesterov; Fermín Aceves de la Cruz; Valeriy A. Luchnikov; Gennady P. Berman

    2015-06-04

    We study theoretically and numerically the conditions required for the appearance of a superradiance transition in graphene. The electron properties of graphene are described in the single $p_z$-orbital tight-binding approximation, in which the model is reduced to the effective two-level pseudo-spin $1/2$ system. For each level we introduce the electron transfer rate of escape into a continuum. We demonstrate that, under some conditions, the superradiance experiences the maximal quantum coherent escape to the continuum.

  3. Vanadium CVV Auger transition

    NASA Astrophysics Data System (ADS)

    Pervan, P.; Valla, T.; Milun, M.

    1996-08-01

    We report an experimental study of the CVV Auger transition of vanadium. A comparison between the experimental spectrum and the self-convolution of the calculated density of states (DOS) failed to show any significant shift between the spectra as reported for Ti and Sc. We have also found good agreement between our experimental and Contini's et al.?l? calculated CVV spectrum of vanadium which may suggest that the screening of the core hole is not as important for the vanadium CVV Auger spectrum as might be expected.

  4. Anticipating critical transitions.

    PubMed

    Scheffer, Marten; Carpenter, Stephen R; Lenton, Timothy M; Bascompte, Jordi; Brock, William; Dakos, Vasilis; van de Koppel, Johan; van de Leemput, Ingrid A; Levin, Simon A; van Nes, Egbert H; Pascual, Mercedes; Vandermeer, John

    2012-10-19

    Tipping points in complex systems may imply risks of unwanted collapse, but also opportunities for positive change. Our capacity to navigate such risks and opportunities can be boosted by combining emerging insights from two unconnected fields of research. One line of work is revealing fundamental architectural features that may cause ecological networks, financial markets, and other complex systems to have tipping points. Another field of research is uncovering generic empirical indicators of the proximity to such critical thresholds. Although sudden shifts in complex systems will inevitably continue to surprise us, work at the crossroads of these emerging fields offers new approaches for anticipating critical transitions. PMID:23087241

  5. Quantum phase transition in space

    SciTech Connect

    Damski, Bogdan [Los Alamos National Laboratory; Zurek, Wojciech H [Los Alamos National Laboratory

    2008-01-01

    A quantum phase transition between the symmetric (polar) phase and the phase with broken symmetry can be induced in a ferromagnetic spin-1 Bose-Einstein condensate in space (rather than in time). We consider such a phase transition and show that the transition region in the vicinity of the critical point exhibits scalings that reflect a compromise between the rate at which the transition is imposed (i.e., the gradient of the control parameter) and the scaling of the divergent healing length in the critical region. Our results suggest a method for the direct measurement of the scaling exponent {nu}.

  6. Radar in transition

    NASA Astrophysics Data System (ADS)

    Barton, D. K.

    1984-12-01

    It is pointed out that radar engineers, at the end of 1984, find their field in transition between the conventional designs of the post War II era and the digitally controlled, solid-state systems which will be in place for the year 2000. The U.S. Navy has two major phased array radar systems in operation, including the rotating three-dimensional (3D) AN/SPS-48, and the phased-scanned AN/SPY-1 (Aegis) radars. The Aegis represents a major step beyond the conventional 3D and mechanical fire-control radars. However, it requires a special ship, dedicated to its use. Attention is given to questions regarding an extension of the application of Aegis technology to other U.S. Navy applications and to other navies, an ambitious solid-state radar program in the UK, and Army radars.

  7. Light Rail Transit Association

    NSDL National Science Digital Library

    Light rail has been an effective form of transportation for many years, and it is quite common in the US and throughout Europe. The Web site of the Light Rail Transit Association (LRTA) has extensive news, historical background, and information about light rail systems. A good overview of light rail is given that outlines its advantages over other transportation methods. One of the best features of the site is its world systems list, which is frequently updated with new light rail projects across the globe. There are also photo galleries of several light rail cars in operation in different countries. Only members can access the LRTA magazines, but the rest of the site's resources are available to anyone.

  8. NASA CONNECT: Venus Transit

    NSDL National Science Digital Library

    2004-01-01

    In this program, students learn about the importance of using scale models to represent the size and distance of objects in the Solar System and beyond. They are introduced to the astronomical unit (AU), the baseline distance from the Earth to the Sun, which astronomers use to determine the relative distances from Earth to other planets, stars, asteroids, and objects in space. They also discover facts about the Venus Transit, a celestial and historical event, which helped astronomers determine the scale of the Solar System. Students use measurement, ratios, and graphing to construct a model of the solar system and determine the relationship of each planet to the Sun. They will explore the scales needed to represent the size of the planets and the distances to the Sun.

  9. Transition Mathematics Project

    NSDL National Science Digital Library

    The Transition Mathematics Project (TMP) was created in 2004 "to help students successfully progress from high school math to college-level math." Since its inception, TMP has worked with a range of partners including high school and college math educators. First-time visitors should check out the Resources area, which includes a number of useful tools such as "Agile Mind" (a web-based platform for educators to develop contextually rich math curricula and instructional materials). The Communication area features a semi-annual newsletter and a compilation of current "Math in the News" articles and publications related to TMP. The Results page features information about the successes of TMP's previous projects with progress reports and other documents.

  10. Presidential Transition Teams: Fostering a Collaborative Transition Process

    ERIC Educational Resources Information Center

    Artman, Richard B.; Franz, Mark

    2009-01-01

    Whether hiring a sitting president or one beginning a first presidency, the board of trustees should be keenly interested in ensuring that the new president's first months in office flow as smoothly as possible. Increasing attention has been paid in recent years to the idea of using a transition team to assist the new president. Using a transition

  11. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Preliminary Evaluation Results

    SciTech Connect

    Chandler, K.; Eudy, L.

    2008-10-01

    This report provides preliminary results from a National Renewable Energy Laboratory evaluation of a protoptye fuel cell transit bus operating at Connecticut Transit in Hartford. Included are descriptions of the planned fuel cell bus demonstration and equipment; early results and agency experience are also provided.

  12. Two Types of Mott Transitions

    Microsoft Academic Search

    Masatoshi Imada

    1993-01-01

    One type of Mott transition (MT1) is characterized by diverging enhancement of the charge effective mass when one approaches a Mott insulator from the side of the paramagnetic metal. Another fundamentally different type of Mott transition (MT2) is shown to exist when a spin gap opens. The linear coefficient of the specific heat gamma decreases and then vanishes at the

  13. Teaching about the Transition Economies.

    ERIC Educational Resources Information Center

    Schug, Mark C.; McCorkle, Sarapage; Morton, John S.

    1998-01-01

    Describes two books of curriculum materials published by the National Council on Economic Education regarding the Central and East European transition economies: (1) "Economies in Transition: Command to Market" (1997); and (2) "From Plan to Market: Teaching Ideas for Social Studies, Economics, and Business Classes" (1997). (DSK)

  14. Pedestrian Safety and Transit Corridors

    Microsoft Academic Search

    Paul Mitchell Hess; Anne Vernez Moudon; Julie M. Matlick

    2003-01-01

    Abstract Abstract Abstract Abstract This research examines the relationship between pedestrian accident locations on state-owned facilities (highways and urban arterials) and the presence of riders load- ing and alighting from bus transit. Many state facilities are important metropolitan transit corridors with large numbers of bus stops users, resulting in increased expo- sure of pedestrians to traffic and in increased numbers

  15. Developmental Transitions in Male Sexuality.

    ERIC Educational Resources Information Center

    Lewis, Robert; And Others

    1978-01-01

    The article defines and elaborates on eight transitions in male sexuality, the first being the gender identity transition, and the last being the male climacteric. It discusses society's lack of support. Originally presented at the American Sociological Association Session on the Male Role in Society, New York City, 1976. (LPG)

  16. Elaborating transition interface sampling methods

    Microsoft Academic Search

    Titus S. van. Erp; Peter G.. Bolhuis

    2005-01-01

    We review two recently developed efficient methods for calculating rate constants of processes dominated by rare events in high-dimensional complex systems. The first is transition interface sampling (TIS), based on the measurement of effective fluxes through hypersurfaces in phase space. TIS improves efficiency with respect to standard transition path sampling (TPS) rate constant techniques, because it allows a variable path

  17. Transition metal transporters in plants

    Microsoft Academic Search

    J. L. Hall; Lorraine E. Williams

    2003-01-01

    Transition metals such as Fe, Cu, Mn, and Zn are essential minerals for normal plant growth and devel- opment, although they can be toxic when present in excess. Thus, for healthy plant growth, a range of transition metals must be acquired from the soil, dis- tributed around the plant, and their concentrations carefully regulated within different cells and orga- nelles.

  18. Partnership Transitions and Maternal Parenting

    ERIC Educational Resources Information Center

    Beck, Audrey N.; Cooper, Carey E.; McLanahan, Sara; Brooks-Gunn, Jeanne

    2010-01-01

    We use data from the Fragile Families and Child Wellbeing Study (N = 1,975) to examine the association between mothers' partnership changes and parenting behavior during the first 5 years of their children's lives. We compare coresidential with dating transitions and recent with more distal transitions. We also examine interactions between…

  19. Spinfluid Phase Transitions

    E-print Network

    Marcus S. Cohen

    2009-07-10

    We start with the spinfluid: a nearly-homogeneous, 8-spinor medium, with small local eddies and twists. As it expends, these seed a raft of intersecting codimension-J singularities: a spinfoam. As this expands, the energy trapped in each (4-J) brane varies as the Jth power of the scale factor. Summing on J=(0,1,2,3,4) creates a quartic dilation potential with either 1 or 2 minima: preferred length and mass scales. The spinfoam expands forever with 1 minimum, but recontracts with 2. To quantize it, we take a canonical ensemble of spinfoams, immersed in a heat bath of vacuum spinors, whose microstates vastly outnumber the matter states. It's evolution is governed by a free energy which admits phase transitions at two critical scale, separated by a triple point.Their critical droplets correspond to the varieties of leptons and hadrons.We identify the first as inflation, the second as baryogenesis; and the heat bath of vacuum spinors as dark energy.

  20. Phase Transition Taylor Test

    NASA Astrophysics Data System (ADS)

    Zhang, Xinghua

    2005-07-01

    In this article, the Taylor impact test is applied to investigate the dynamic phase transformation behavior of NiTi alloy, which we call it the phase transition Taylor test (PTTT). The symmetry impact configuration is applied in the study at impact velocity range from 47m/s to 175m/s by using a light gas gun facility in this lab. The NiTi alloy is treated in the state of shape memory effect (SME). The shape of the recovered samples is substantially different from that of traditional elastic-plastic Taylor test. The recovered NiTi bar can be divided into three deformation regions from the impact surface: the main deformation region with homogeneous deformation, the gradient deformation region and the elastic region successively, which correspond to the martensitic phase, mixed phase and austenite, respectively. The different deformation regions demonstrate the interaction between the dynamic phase boundary and the rarefaction wave reflected from the free end of the bar. Simulation with the macroscopic phase boundary propagation theory[1]is in good agreement with the experimental measurement. [1] Dai X et al, International Journal of Impact Engineering, 30(4)(2004), 385.

  1. Transitions: From Pediatric to Adult Health Care

    MedlinePLUS

    ... Businesses & Schools > Transitions Transitions From Pediatric to Adult Health Care Transitioning from teenage years to adulthood can be ... management and make more independent judgments about their health care needs. NDEP has assembled the materials below to ...

  2. 21 December 2007 Light Rail Transit Construction

    E-print Network

    Levinson, David M.

    21 December 2007 Light Rail Transit Construction Impact Mitigation Strategies: Case Studies and Recommendations for the Central Corridor #12;Light Rail Transit Construction Impact Mitigation Strategies: Case Rail Transit Construction Impact Mitigation Strategies 21 December 2007 i TABLE OF CONTENTS

  3. OAKLAND TRANSIT CONNECTOR DOWNTOWN PITTSBURGH TO OAKLAND

    E-print Network

    Blelloch, Guy E.

    OAKLAND TRANSIT CONNECTOR AND DOWNTOWN PITTSBURGH TO OAKLAND CONNECTOR PITTSBURGH, PA Project;Oakland-Downtown/Oakland Transit Connector TRANSPORTATION ACTION PARTNERSHIP Project Information Document......................................................................... 8 3.0 OAKLAND TRANSIT CONNECTOR

  4. Parity nonconservation in atomic Zeeman transitions

    SciTech Connect

    Angstmann, E. J.; Dinh, T. H.; Flambaum, V. V. [School of Physics, University of New South Wales, Sydney 2052 (Australia)

    2005-11-15

    We discuss the possibility of measuring nuclear anapole moments in atomic Zeeman transitions and perform the necessary calculations. Advantages of using Zeeman transitions include variable transition frequencies and the possibility of enhancement of parity nonconservation effects.

  5. Phase Transition in Reconstituted Chromatin

    E-print Network

    Tonau Nakai; Kohji Hizume; Shige. H. Yoshimura; Kunio Takeyasu; Kenichi Yoshikawa

    2004-09-10

    By observing reconstituted chromatin by fluorescence microscopy (FM) and atomic force microscopy (AFM), we found that the density of nucleosomes exhibits a bimodal profile, i.e., there is a large transition between the dense and dispersed states in reconstituted chromatin. Based on an analysis of the spatial distribution of nucleosome cores, we deduced an effective thermodynamic potential as a function of the nucleosome-nucleosome distance. This enabled us to interpret the folding transition of chromatin in terms of a first-order phase transition. This mechanism for the condensation of chromatin is discussed in terms of its biological significance.

  6. Selenophene transition metal complexes

    SciTech Connect

    White, C.J.

    1994-07-27

    This research shows that selenophene transition metal complexes have a chemistry that is similar to their thiophene analogs. Selenophene coordination has been demonstrated and confirmed by molecular structure in both the {eta}{sup 5}- and the {eta}{sup 1}(Se)-coordination modes. The reaction chemistry of selenophene complexes closely resembles that of the analogous thiophene complexes. One major difference, however, is that selenophene is a better donor ligand than thiophene making the selenophene complexes more stable than the corresponding thiophene complexes. The {sup 77}Se NMR chemical shift values for selenophene complexes fall within distinct regions primarily depending on the coordination mode of the selenophene ligand. In the final paper, the C-H bond activation of {eta}{sup 1}(S)-bound thiophenes, {eta}{sup 1}(S)-benzothiophene and {eta}{sup 1}(Se)-bound selenophenes has been demonstrated. The deprotonation and rearrangement of the {eta}{sup 1}(E)-bound ligand to the carbon bound L-yl complex readily occurs in the presence of base. Reprotonation with a strong acid gives a carbene complex that is unreactive towards nucleophilic attack at the carbene carbon and is stable towards exposure to air. The molecular structure of [Cp(NO)(PPh{sub 3})Re(2-benzothioenylcarbene)]O{sub 3}SCF{sub 3} was determined and contains a Re-C bond with substantial double bond character. Methyl substitution for the thienylcarbene or selenylcarbene gives a carbene that rearranges thermally to give back the {eta}{sup 1}(E)-bound complex. Based on these model reactions, a new mechanism for the H/D exchange of thiophene over the hydrodesulfurization catalyst has been proposed.

  7. Transition States, analogues, and drug development.

    PubMed

    Schramm, Vern L

    2013-01-18

    Enzymes achieve their transition states by dynamic conformational searches on the femtosecond to picosecond time scale. Mimics of reactants at enzymatic transition states bind tightly to enzymes by stabilizing the conformation optimized through evolution for transition state formation. Instead of forming the transient transition state geometry, transition state analogues convert the short-lived transition state to a stable thermodynamic state. Enzymatic transition states are understood by combining kinetic isotope effects and computational chemistry. Analogues of the transition state can bind millions of times more tightly than substrates and show promise for drug development for several targets. PMID:23259601

  8. Personal Rapid Transit Minneapolis, Minnesota

    E-print Network

    Minnesota, University of

    Workshop Goals and Context and Summary of RFI Responses .................... 3 RFI Responses............................................................................................ 3 RFI Responders' Comments...................................................................... 5/DOT commissioner Tom Sorel said the agency issued the RFI to see if personal rapid transit is a viable

  9. Regulating competition: Transition or travesty?

    SciTech Connect

    Cicchetti, C.J.; Sepetys, K.M.

    1996-05-01

    The coming of competition in California and elsewhere will not mean less regulation but more - at least in the short run. The acid test of the transition will be whether the responsible political officials can define and impose {open_quotes}competitive transition charge{close_quotes} on a basis that is fair to all parties, and then hold fast against customer pressures to avoid it.

  10. A Decade of Fiscal Transition

    Microsoft Academic Search

    Asad Alam; Mark Sundberg

    2002-01-01

    Transition literature has emphasized stabilization and enterprise restructuring. Both cross-country analyses and country-specific studies have tended to focus on fiscal stabilization and its indicators, highlighting the importance of quantitative fiscal adjustment to stabilization outcomes. Less attention has been paid to the qualitative dimensions of fiscal adjustment in transition.Alam and Sundberg take stock of the extent to which fiscal adjustment has

  11. Universal Keplerian state transition matrix

    NASA Technical Reports Server (NTRS)

    Shepperd, S. W.

    1985-01-01

    A completely general method for computing the Keplerian state transition matrix in terms of Goodyear's universal variables is presented. This includes a new scheme for solving Kepler's problem which is a necessary first step to computing the transition matrix. The Kepler problem is solved in terms of a new independent variable requiring the evaluation of only one transcendental function. Furthermore, this transcendental function may be conveniently evaluated by means of a Gaussian continued fraction.

  12. Universal Keplerian state transition matrix

    NASA Astrophysics Data System (ADS)

    Shepperd, S. W.

    1985-02-01

    A completely general method for computing the Keplerian state transition matrix in terms of Goodyear's universal variables is presented. This includes a new scheme for solving Kepler's problem which is a necessary first step to computing the transition matrix. The Kepler problem is solved in terms of a new independent variable requiring the evaluation of only one transcendental function. Furthermore, this transcendental function may be conveniently evaluated by means of a Gaussian continued fraction.

  13. Hurricanes Canadian Style: Extratropical Transition

    NSDL National Science Digital Library

    COMET

    2002-05-02

    This Webcast is based on a presentation delivered by Jim Abraham of MSC at the Winter Weather Course in February 2001. The presentation discusses how, under the right synoptic conditions, hurricanes and tropical storms undergo a transition process to extratropical cyclones as they move into northern latitudes. During the transition process these "hybrid" systems can bring damaging weather conditions to Eastern Canada and the Northeastern States. It uses several case examples to demonstrate the process.

  14. Modelling the transitional boundary layer

    NASA Technical Reports Server (NTRS)

    Narasimha, R.

    1990-01-01

    Recent developments in the modelling of the transition zone in the boundary layer are reviewed (the zone being defined as extending from the station where intermittency begins to depart from zero to that where it is nearly unity). The value of using a new non-dimensional spot formation rate parameter, and the importance of allowing for so-called subtransitions within the transition zone, are both stressed. Models do reasonably well in constant pressure 2-dimensional flows, but in the presence of strong pressure gradients further improvements are needed. The linear combination approach works surprisingly well in most cases, but would not be so successful in situations where a purely laminar boundary layer would separate but a transitional one would not. Intermittency-weighted eddy viscosity methods do not predict peak surface parameters well without the introduction of an overshooting transition function whose connection with the spot theory of transition is obscure. Suggestions are made for further work that now appears necessary for developing improved models of the transition zone.

  15. Spin transitions in FeSpin transitions in Fe Fairy-tale I: What are the spin transitions?

    E-print Network

    Cerveny, Vlastislav

    Spin transitions in FeSpin transitions in Fe Fairy-tale I: What are the spin transitions? Fairy IS LS at 120 GPa #12;#12;Iron spin transition in Earth's mantle S. Speziale, A. Milner, V. E. Lee, S. M, the discovery of spin-pairing in mantle minerals under high pressure has led to a renewed interest in radiative

  16. Transition boiling heat transfer and the film transition regime

    NASA Technical Reports Server (NTRS)

    Ramilison, J. M.; Lienhard, J. H.

    1987-01-01

    The Berenson (1960) flat-plate transition-boiling experiment has been recreated with a reduced thermal resistance in the heater, and an improved access to those portions of the transition boiling regime that have a steep negative slope. Tests have been made in Freon-113, acetone, benzene, and n-pentane boiling on horizontal flat copper heaters that have been mirror-polished, 'roughened', or teflon-coated. The resulting data reproduce and clarify certain features observed by Berenson: the modest surface finish dependence of boiling burnout, and the influence of surface chemistry on both the minimum heat flux and the mode of transition boiling, for example. A rational scheme of correlation yields a prediction of the heat flux in what Witte and Lienhard (1982) previously identified as the 'film-transition boiling' region. It is also shown how to calculate the heat flux at the boundary between the pure-film, and the film-transition, boiling regimes, as a function of the advancing contact angle.

  17. Boundary layer transition studies

    NASA Technical Reports Server (NTRS)

    Watmuff, Jonathan H.

    1995-01-01

    A small-scale wind tunnel previously used for turbulent boundary layer experiments was modified for two sets of boundary layer transition studies. The first study concerns a laminar separation/turbulent reattachment. The pressure gradient and unit Reynolds number are the same as the fully turbulent flow of Spalart and Watmuff. Without the trip wire, a laminar layer asymptotes to a Falkner & Skan similarity solution in the FPG. Application of the APG causes the layer to separate and a highly turbulent and approximately 2D mean flow reattachment occurs downstream. In an effort to gain some physical insight into the flow processes a small impulsive disturbance was introduced at the C(sub p) minimum. The facility is totally automated and phase-averaged data are measured on a point-by-point basis using unprecedently large grids. The evolution of the disturbance has been tracked all the way into the reattachment region and beyond into the fully turbulent boundary layer. At first, the amplitude decays exponentially with streamwise distance in the APG region, where the layer remains attached, i.e. the layer is viscously stable. After separation, the rate of decay slows, and a point of minimum amplitude is reached where the contours of the wave packet exhibit dispersive characteristics. From this point, exponential growth of the amplitude of the disturbance is observed in the detached shear layer, i.e. the dominant instability mechanism is inviscid. A group of large-scale 3D vortex loops emerges in the vicinity of the reattachment. Remarkably, the second loop retains its identify far downstream in the turbulent boundary layer. The results provide a level of detail usually associated with CFD. Substantial modifications were made to the facility for the second study concerning disturbances generated by Suction Holes for laminar flow Control (LFC). The test section incorporates suction through interchangeable porous test surfaces. Detailed studies have been made using isolated holes in the impervious test plate that used to establish the Blasius base flow. The suction is perturbed harmonically and data are averaged on the basis of the phase of the disturbance, for conditions corresponding to strong suction and without suction. The technique was enhanced by using up to nine multiple probes to reduce the experimental run-time. In both cases, 3D contour surfaces in the vicinity of the hole show highly 3D TS waves which fan out in the spanwise direction forming bow-shaped waves downstream. The case without suction has proved useful for evaluating calculation methods. With suction, the perturbations on the centerline are much stronger and decay less rapidly, while the TS waves in the far field are similar to the case without suction. Downstream, the contour surfaces of the TS waves develop spanwise irregularities which eventually form into clumps. The spanwise clumping is evidence of a secondary instability that could be associated with suction vortices. Designers of porous surfaces use Goldsmith's Criterion to minimize cross-stream interactions. It is shown that partial TS wave cancellation is possible, depending on the hole spacing, disturbance frequency and free-stream velocity. New high-performance Constant Temperature Hot-Wire Anemometers were designed and built, based on a linear system theory analysis that can be extended to arbitrary order. The motivation was to achieve the highest possible frequency reponse while ensuring overall system stability. The performance is equal to or superior to commercially available instruments at about 10% of the cost. Details, such as fabrication drawings and a parts list, have been published to enable the instrument to be construced by others.

  18. Quantum Transport in Transition Metal Oxides

    E-print Network

    Takada, Yasutami

    Quantum Transport in Transition Metal Oxides Anomalous transport properties in transition metal to strong correlation. Another aspect of the transition-metal oxides, in particular in manganese the anomalous current in transition-metal compounds from a viewpoint of the band theory, we have recently

  19. Transit price elasticities and cross-elasticities

    Microsoft Academic Search

    Todd Litman

    2007-01-01

    This paper summarises price elasticities and cross elasticities for use in public transit planning. It describes how elasticities are used, and summarizes previous research on transit elasticities. Commonly used transit elasticity values are largely based on studies of short and medium run impacts performed decades ago when real incomes were lower and a larger portion of the population was transit

  20. Collision avoidance analysis for transition taper length

    Microsoft Academic Search

    Jinxian Weng

    2011-01-01

    Transition taper length plays a vitally important role in work zone safety operations because too short a transition taper length will result in higher accident risks and too long a transition taper length could increase traffic delay. This paper evaluates transition taper length under various traffic conditions and road geometries using collision avoidance analysis. The longitudinal distances for lane changing

  1. Porcupine-like horseshoes: Transitivity, Lyapunov spectrum, and phase transitions

    E-print Network

    Díaz, L J

    2010-01-01

    We study a partially hyperbolic and topologically transitive local diffeomorphism $F$ that is a skew-product over a horseshoe map. This system is derived from a homoclinic class and contains infinitely many hyperbolic periodic points of different indices and hence is not hyperbolic. The associated transitive invariant set $\\Lambda$ possesses a very rich fiber structure, it contains uncountably many trivial and uncountably many non-trivial fibers. Moreover, the spectrum of the central Lyapunov exponents of $F|_{\\Lambda}$ contains a gap and hence gives rise to a first order phase transition. A major part of the proofs relies on the analysis of an associated iterated function system that is genuinely non-contracting.

  2. Lithium iodate: Phase transitions revisited

    NASA Astrophysics Data System (ADS)

    Crettez, Jean-Michel; Coquet, Etienne; Michaux, Bernard; Pannetier, Jean; Bouillot, Jacques; Orlans, Patrick; Nonat, André; Mutin, Jean-Claude

    1987-03-01

    The sequence of phase transitions of lithium iodate powders has been investigated by neutron thermodiffractometry. Upon heating, powders obtained by grinding hexagonal crystals exhibit the well known ? ? ? ? ? sequence. The intermediate orthorhombic phase ? is never observed as a single phase but always coexists either with ? or with ?-LiIO 3. The transition temperatures and the ? ? ? transformation rate are found to be strongly dependent on the crystallite dimension, especially for grain sizes smaller than 100 ?m. The hysteresis of the reversible ? ? ? transition, the kinetics of both ? ? ? and ? ? ? transitions, and the influence of proton contamination are also investigated. Contrary to this, natural powders obtained by fast evaporation of an aqueous solution do not exhibit any intermediate phase and transform directly from ? to the ? tetragonal modification. Further DTA and X-ray investigations show that the occurrence of the ? phase is related to the mechanical treatment of the sample (grinding, polishing…), i.e. to the presence of defects. Previous literature data are reviewed and the apparent discrepancies concerning the transition processes are elucidated on the basis of the present results.

  3. Transitional care in pediatric urology.

    PubMed

    Lambert, Sarah M

    2015-04-01

    The transition from childhood to adolescence and into adulthood occurs as a natural component of human development. As children progress through school and gain independence, health care practitioners must facilitate a parallel transition from pediatric to adult providers. Modern medicine has succeeded in extending the life expectancy for many children with complex conditions, and adult providers are participating in their medical care through adulthood. Transitioning pediatric urology care to adult urology care is unique to every individual and his or her underlying condition, while the transition process is universal. The objectives of all pediatric urologists include preservation of the kidneys and lower urinary tracts, safe urine storage, safe urine drainage, urinary continence, fertility, sexual function, and genital cosmesis. For some children, these objectives can be attained during childhood, while other children require lifelong maintenance and management. Children with posterior urethral valves, exstrophy-epispadias complex, cloaca, vesicoureteral reflux, neurogenic bladder, disorders of sex development, cancer, hypospadias, nephrolithiasis, undescended testes, varicoceles, ureteropelvic junction obstruction, solitary kidney, and upper tract anomalies all require long-term evaluation and management. The obstacles of altering a patient and caregiver paradigm, locating adult urologists with special expertise, coordinating care with other adult specialties such as nephrology, and navigating the adult health care environment can impede the transition process. PMID:25770367

  4. Hubble's View of Transiting Planets

    E-print Network

    David Charbonneau

    2004-10-27

    The Hubble Space Telescope is uniquely able to study planets that are observed to transit their parent stars. The extremely stable platform afforded by an orbiting spacecraft, free from the contaminating effects of the Earth's atmosphere, enables HST to conduct ultra-high precision photometry and spectroscopy of known transiting extrasolar planet systems. Among HST's list of successful observations of the first such system, HD 209458, are (1) the first detection of the atmosphere of an extrasolar planet, (2) the determination that gas is escaping from the planet, and (3) a search for Earth-sized satellites and circumplanetary rings. Numerous wide-field, ground-based transit surveys are poised to uncover a gaggle of new worlds for which HST may undertake similar studies, such as the newly-discovered planet TrES-1. With regard to the future of Hubble, it must be noted that it is the only observatory in existence capable of confirming transits of Earth-like planets that may be detected by NASA's Kepler mission. Kepler could reveal Earth-like transits by the year 2010, but without a servicing mission it is very unlikely that HST would still be in operation.

  5. UV transition moments of tyrosine.

    PubMed

    Fornander, Louise H; Feng, Bobo; Beke-Somfai, Tamás; Nordén, Bengt

    2014-08-01

    To assist polarized-light spectroscopy for protein-structure analysis, the UV spectrum of p-cresol, the chromophore of tyrosine, was studied with respect to transition moment directions and perturbation by solvent environment. From linear dichroism (LD) spectra of p-cresol aligned in stretched matrices of poly(vinyl alcohol) and polyethylene, the lowest ?-?* transition (Lb) is found to have pure polarization over its entire absorption (250-300 nm) with a transition moment perpendicular to the symmetry axis (C1-C4), both in polar and nonpolar environments. For the second transition (La), polarized parallel with the symmetry axis, a certain admixture of intensity with orthogonal polarization is noticed, depending on the environment. While the Lb spectrum in cyclohexane shows a pronounced vibrational structure, it is blurred in methanol, which can be modeled as due to many microscopic polar environments. With the use of quantum mechanical (QM) calculations, the transition moments and solvent effects were analyzed with the B3LYP and ?B97X-D functionals in cyclohexane, water, and methanol using a combination of implicit and explicit solvent models. The blurred Lb band is explained by solvent hydrogen bonds, where both accepting and donating a hydrogen causes energy shifts. The inhomogeneous solvent-shift sensitivity in combination with robust polarization can be exploited for analyzing tyrosine orientation distributions in protein complexes using LD spectroscopy. PMID:25020040

  6. Electronic Transitions of Ruthenium Monoxide

    NASA Astrophysics Data System (ADS)

    Wang, Na; Ng, Y. W.; Cheung, A. S.-C.

    2013-06-01

    The electronic transition spectrum of ruthenium monoxide (RuO) molecule in the spectral region between 545nm to 640nm has been recorded and analyzed using laser ablation/reaction free-jet expansion and laser induced fluorescence spectroscopy. The RuO molecule was produced by reacting laser- ablated ruthenium atoms with N_{2}O seeded in argon. Nine vibrational bands were recorded and they are identified to be belonging to four electronic transition systems, namely the [18.1]? = 4 - X^{5} ?_4 transition, [16.0]^{5} ?_5 - X^{5} ?_4 transition, [18.1]? = 3 - X^{5} ?_3, and [15.8] ^{5} ?_4 - X^{5} ?_3 transition. RuO has been determined to have a X^{5} ?_4 ground state. A least squares fit of the measured rotational lines yielded molecular constants for the ground and the low-lying electronic states. A molecular orbital energy level diagram has been used to help with the assignment of the observed electronic states.

  7. Transition metals in superheat melts

    NASA Technical Reports Server (NTRS)

    Jakes, Petr; Wolfbauer, Michael-Patrick

    1993-01-01

    A series of experiments with silicate melts doped with transition element oxides was carried out at atmospheric pressures of inert gas at temperatures exceeding liquidus. As predicted from the shape of fO2 buffer curves in T-fO2 diagrams the reducing conditions for a particular oxide-metal pair can be achieved through the T increase if the released oxygen is continuously removed. Experimental studies suggest that transition metals such as Cr or V behave as siderophile elements at temperatures exceeding liquidus temperatures if the system is not buffered by the presence of other oxide of more siderophile element. For example the presence of FeO prevents the reduction of Cr2O3. The sequence of decreasing siderophility of transition elements at superheat conditions (Mo, Ni, Fe, Cr) matches the decreasing degree of depletion of siderophile elements in mantle rocks as compared to chondrites.

  8. Cellular Transitions and Tissue Engineering

    PubMed Central

    Kolind, Mille; Little, David G.

    2013-01-01

    Abstract Epithelial-to-mesenchymal transition (EMT) and endothelial-to-mesenchymal transition (EndMT) describe complex changes in progenitor lineage, cell morphology, and gene expression. Stimulated by environmental cues, these cellular transitions are essential for elements of embryonic development and can be pathologically dysregulated in disease states. EMT occurs in biological processes such as gastrulation, cardiogenesis, and fibrosis. EndMT is involved in development and tissue fibrosis, but recent studies have implicated this process in musculoskeletal biology and pathology. Tissue engineering and regenerative medicine typically rely on endogenous progenitors or progenitors expanded ex vivo to repair damaged or impaired tissues or organs. The processes of EMT and EndMT may aid in elucidating new methods for reducing fibrosis and identifying novel plastic progenitor populations for tissue repair. This review will discuss the potential for EMT and EndMT to impact on tissue engineering and regenerative medicine. PMID:23550730

  9. Understanding epidemiological transition in India

    PubMed Central

    Yadav, Suryakant; Arokiasamy, Perianayagam

    2014-01-01

    Background Omran's theory explains changing disease patterns over time predominantly from infectious to chronic noncommunicable diseases (NCDs). India's epidemiological transition is characterized by dual burden of diseases. Kumar addressed low mortality and high morbidity in Kerala, which seems also to be true for India as a country in the current demographic scenario. Methods NSS data (1986–1987, 1995–1996, 2004) and aggregated data on causes of death provided by Registrar General India (RGI) were used to examine the structural changes in morbidity and causes of death. A zero-inflated poisson (ZIP) regression model and a beta-binomial model were used to corroborate the mounting age pattern of morbidity. Measures, namely the 25th and 75th percentiles of age-at-death and modal age-at-death, were used to examine the advances in mortality transition. Objective This study addressed the advances in epidemiological transition via exploring the structural changes in pattern of diseases and progress in mortality transition. Results The burden of NCDs has been increasing in old age without replacing the burden of communicable diseases. The manifold rise of chronic diseases in recent decades justifies the death toll and is responsible for transformation in the age pattern of morbidity. Over time, deaths have been concentrated near the modal age-at-death. Modal age-at-death increased linearly by 5 years for females (r2=0.9515) and males (r2=0.9020). Significant increase in modal age-at-death ascertained the dominance of old age mortality over the childhood/adult age mortality. Conclusions India experiences a dual burden of diseases associated with a remarkable transformation in the age pattern of morbidity and mortality, contemporaneous with structural changes in disease patterns. Continued progress in the pattern of diseases and mortality transition, accompanied by a linear rise in ex, unravels a compelling variation in advances found so far in epidemiological transition witnessed by the developed nations, with similar matrices for India. PMID:24848651

  10. Finding Transition Pathways on Manifolds

    E-print Network

    Tiejun Li; Xiaoguang Li; Xiang Zhou

    2014-08-13

    We consider noise-induced transition paths in randomly perturbed dynami- cal systems on a smooth manifold. The classical Freidlin-Wentzell large devia- tion theory in Euclidean spaces is generalized and new forms of action functionals are derived in the spaces of functions and the space of curves to accommodate the intrinsic constraints associated with the manifold. Numerical meth- ods are proposed to compute the minimum action paths for the systems with constraints. The examples of conformational transition paths for a single and double rod molecules arising in polymer science are numerically investigated.

  11. Topological transitions in spin interferometers

    NASA Astrophysics Data System (ADS)

    Saarikoski, Henri; Vázquez-Lozano, J. Enrique; Baltanás, José Pablo; Nagasawa, Fumiya; Nitta, Junsaku; Frustaglia, Diego

    2015-06-01

    We show that topological transitions in electronic spin transport are feasible by a controlled manipulation of spin-guiding fields. The transitions are determined by the topology of the fields texture through an effective Berry phase (related to the winding parity of spin modes around poles in the Bloch sphere), irrespective of the actual complexity of the nonadiabatic spin dynamics. This manifests as a distinct dislocation of the interference pattern in the quantum conductance of mesoscopic loops. The phenomenon is robust against disorder, and can be experimentally exploited to determine the magnitude of inner spin-orbit fields.

  12. William Crabtree's Venus transit observation

    NASA Astrophysics Data System (ADS)

    Kollerstrom, Nicholas

    2005-04-01

    The close collaboration between the two North-country astronomers Jeremiah Horrocks and William Crabtree gave them special insight into the new astronomy published by the recently-deceased Kepler, whereby Horrocks became the only person to apprehend that the Rudolphine tables were in fact predicting a Venus transit in 1639. This paper focuses especially upon William Crabtree's role and contribution. A comparison is made with an earlier, unsuccessful endeavour by these two concerning a possible transit of Mercury. Much of the record of their work was lost during the civil war. Finally, thanks to Christiaan Huygens, Horrock's manuscript was published by Johannes Hevelius in Danzig, in 1662.

  13. Decoherence after a phase transition

    E-print Network

    Lombardo, F C; Rivers, R J

    2001-01-01

    We analyze the onset of classical behaviour after a second-order phase transition in quantum field theory. We consider a scalar theory in which the system-field interacts with its environment, represented both by further scalar fields and by its own short-wavelength modes. We compute the decoherence time for the system-field modes and compare it with the other time scales of the model. Within our approximations we see that the long-wavelength modes have decohered by the time that the transition has been first implemented (the spinodal time)

  14. Disorder driven quantum phase transitions in transition metal oxides

    Microsoft Academic Search

    Kohjiro Kobayashi; Nandini Trivedi

    2007-01-01

    We investigate the effect of disorder on a class of transition metal oxides described by a single orbital Hubbard model at half filling and away from half filling. The phases are characterized by the nature of the electronic and spin excitations. We calculate the local density of states, frequency and temperature-dependent conductivity and spin susceptibility as functions of disorder and

  15. Transition metal sulfide loaded catalyst

    DOEpatents

    Maroni, Victor A. (Naperville, IL); Iton, Lennox E. (Downers Grove, IL); Pasterczyk, James W. (Westmont, IL); Winterer, Markus (Westmont, IL); Krause, Theodore R. (Lisle, IL)

    1994-01-01

    A zeolite based catalyst for activation and conversion of methane. A zeolite support includes a transition metal (Mo, Cr or W) sulfide disposed within the micropores of the zeolite. The catalyst allows activation and conversion of methane to C.sub.2 + hydrocarbons in a reducing atmosphere, thereby avoiding formation of oxides of carbon.

  16. Transition metal sulfide loaded catalyst

    DOEpatents

    Maroni, V.A.; Iton, L.E.; Pasterczyk, J.W.; Winterer, M.; Krause, T.R.

    1994-04-26

    A zeolite-based catalyst is described for activation and conversion of methane. A zeolite support includes a transition metal (Mo, Cr or W) sulfide disposed within the micropores of the zeolite. The catalyst allows activation and conversion of methane to C[sub 2]+ hydrocarbons in a reducing atmosphere, thereby avoiding formation of oxides of carbon.

  17. Korean telecommunication industry in transition

    Microsoft Academic Search

    Dong-wan Tcha; June S. Park; Suk-gwon Chang; Kwan Ho Song

    2000-01-01

    This paper, as a preface to this special issue, gives an overview of recent developments in Korean telecommunication market and industry. It provides background information that is helpful for understanding the motivations behind research papers contained in this issue. In particular, we discuss the transition of the market structure from monopoly to deregulated competition, the activities in telecommunications R&D, and

  18. Poland's Transition in Business Education

    ERIC Educational Resources Information Center

    Leven, Bozena

    2010-01-01

    Prior to Poland's transition from central planning to a market system, which began in 1990, schools of business were non-existent in that country. Instead, university level instruction on economics during the socialist period was closely tied to ideological priorities, and limited to imparting skills suitable for planned economy. All universities…

  19. Transition-fault test generation

    E-print Network

    Cobb, Bradley Douglas

    2013-02-22

    large to store in the memory of the tester. The proposed methods of test generation utilize stuck-at-fault tests to create transition-fault test sets of a smaller size. Greedy algorithms are used in the generation of both the stuck...

  20. Dynamics of the LTD Transition

    NASA Astrophysics Data System (ADS)

    Oran, Elaine S.

    2008-11-01

    The laminar flame to turbulent flame to detonation transition in a chemically reactive medium is a highly transient, complex, and dynamic process in which there are continuous qualitative and quantitative changes in the state of the gas. The transition begins with an initially small flame or spark that evolves into a turbulent flame, producing compression and shock waves. The shocks, in turn, may couple with the flame to form unsteady, propagating shock-flame complexes that may transition to a detonation. The complete process is illustrated here with videos made from numerical solutions of the multidimensional, unsteady, chemically reacting, Navier-Stokes equations. The discussion focuses on selected features of the flow, including: formation of a turbulent flame and the nature of the turbulence, shock-wave transitions from single to double Mach reflection, creation of hot spots as the origins of detonations, and comparisons between simulations and experimental data. (This work is done in collaboration with Vadim N. Gamezo, Takanobu Ogawa, David A. Kessler, and Alexei Poludnenko, and is sponsored by ONR, NIOSH, NASA, and NEDO.)

  1. Portfolios: Transitioning to the Future.

    ERIC Educational Resources Information Center

    Pond, Beth N.; Burdick, Susan E.; Yamamoto, Joanne K.

    1998-01-01

    The Career Life Plan is a portfolio-based tool for preparing for life transitions. It includes career preparation and assessment information, resumes, interpersonal skills development, writing samples, applications, and letters of recommendation. This working tool reflects students' learning styles, personality types, and career interests. (SK)

  2. Understanding Student Veterans in Transition

    ERIC Educational Resources Information Center

    Jones, Kevin C.

    2013-01-01

    In this research report the author details a phenomenological study documenting identity development in student veterans making the transition from active military service to higher education. This study took place at a doctoral granting proprietary university with a significant veteran population and consisted of in-depth interviews. This…

  3. Symmetry structure and phase transitions

    E-print Network

    Ashok Goyal; Meenu Dahiya; Deepak Chandra

    2002-01-22

    We study chiral symmetry structure at finite density and temperature in the presence of external magnetic field and gravity, a situation relevant in the early Universe and in the core of compact stars. We then investigate the dynamical evolution of phase transition in the expanding early Universe and possible formation of quark nuggets and their survival.

  4. Transition: Principles, Policy, and Premises.

    ERIC Educational Resources Information Center

    Busby, Howard R.; Danek, Marita M.

    1998-01-01

    Traces changes in policy and legislation that have led to the provision of transition services for students who are deaf and hard of hearing. Describes provisions in the 1992 Amendments to the Rehabilitation Act, the Individuals with Disabilities Education Act, and the School-to-Work Opportunities Act. (CR)

  5. Transitive Softening in Russian Conjugation

    ERIC Educational Resources Information Center

    Coats, H. S.; Lightner, T. M.

    1975-01-01

    Transitive softening, or the shift of a dental or velar to a palato-alveolar, and the insertion of a palatalized /1/ after a labial, are examined. The older transformational cycle of Halle is set aside in favor of a morphological rule. Productive and non-productive verb classes are analyzed. (SC)

  6. Controlled quantum evolutions and transitions

    Microsoft Academic Search

    Nicola Cufaro Petroni; Salvatore De Martino; Silvio De Siena; Fabrizio Illuminati

    1999-01-01

    We study the nonstationary solutions of Fokker-Planck equations associated to either stationary or non stationary quantum states. In particular, we discuss the stationary states of quantum systems with singular velocity fields. We introduce a technique that allows arbitrary evolutions ruled by these equations to account for controlled quantum transitions. As a first signficant application we present a detailed treatment of

  7. Career Transitions: The Australian Experience.

    ERIC Educational Resources Information Center

    Stevens, Paul

    This book is designed to aid career counselors in Australia help their clients search for enhanced well-being in their occupations and to help organizations and human resource staff members dealing with employees' career development. The book is organized in four parts. Parts 1 and 2 explore the career transition journey that a typical person…

  8. Preterm Birth: Transition to Adulthood

    ERIC Educational Resources Information Center

    Allen, Marilee C.; Cristofalo, Elizabeth; Kim, Christina

    2010-01-01

    Preterm birth is associated with greater difficulty with transitions from childhood to adolescence to adulthood. Adolescents and young adults born preterm have higher rates of cerebral palsy, intellectual disability, cognitive impairment, learning disability, executive dysfunction, attention deficit disorder, and social-emotional difficulties than…

  9. Parent Involvement in Transition Programs.

    ERIC Educational Resources Information Center

    McNair, Jeff; Rusch, Frank R.

    This survey of 85 parents of children with handicaps (ages 14-25) assesses the involvement of parents in the transition process of the young person from home to work or independent living, the kind of involvement they desire, and responsibilities they would be willing to assume in order to be involved. Findings show that although more than…

  10. Transition Education as Critical Practice

    ERIC Educational Resources Information Center

    Tobias, Robert

    2006-01-01

    This paper explores the nature and role of those forms of tertiary education that have been variously described as "transition", "foundation" and "bridging" education. It argues that much of the relevant literature is grounded implicitly or explicitly in technicist and liberal functionalist discourses. It then reviews and critiques some of this…

  11. Post-Graduate Transitional Programs

    E-print Network

    Subramanian, Venkat

    , to explore a career field, or to gain experience before starting graduate or professional school. · Transitional programs may pay a salary, a stipend or help pay back student loans. Tips for finding a program ­ Education Peace Corps ­ International Public Affairs Reporting Program ­ Government Seattle Rep Post-Grad

  12. Glow discharges in transitional regimes

    Microsoft Academic Search

    K. G. Emeleus

    1974-01-01

    Attention is called to the paucity of experimental information about the fields and charged particle number densities in the transitional regimes between simple and dense discharges, for small electrode separation, and simple and normal discharges for large electrode separation, and to the occurrence of radial constriction in the latter some-what like that in normal discharges. Methods are suggested for ascertaining

  13. Femtosecond Absorption Spectroscopy of Transition

    E-print Network

    McCusker, James K.

    Femtosecond Absorption Spectroscopy of Transition Metal Charge-Transfer Complexes JAMES K. MCCUSKER ABSTRACT Our research is concerned with the application of femtosecond time-resolved absorption techniques, where semiconductors are the functional element of most photovoltaic devices, absorption of light leads

  14. Making the transition to automation

    Microsoft Academic Search

    1992-01-01

    By 1995, the Bureau of Reclamation's hydropower plant near Hungry Horse, Montana, will be remotely operated from Grand Coulee dam (about 300 miles away) in Washington State. Automation at Hungry Horse will eliminate the need for four full-time power plant operators. Between now and then, a transition plan that offers employees choices for retraining, transferring, or taking early retirement will

  15. American Higher Education in Transition

    ERIC Educational Resources Information Center

    Ehrenberg, Ronald G.

    2011-01-01

    American higher education is in transition and if there ever was a "golden age" for faculty, it probably is behind us. The best historical data on the composition of faculty is collected annually by the American Mathematical Society. Between 1967 and 2009, the share of full-time faculty with PhDs remained constant at about 90 percent at doctoral…

  16. Transition Radiation Detector in MACRO

    Microsoft Academic Search

    Mario Nicola Mazziotta

    1999-01-01

    The MACRO detector is located in the Gran Sasso Laboratory. MACRO's overburden varies from to ? . A transition radiation detector (TRD) has been added to the MACRO detector in order to measure the residual energy of muons entering MACRO, i.e. the energy they have after passing through the Gran Sasso's rock overburden. The TRD consists of three identical modules

  17. Life in the Transition Economies.

    ERIC Educational Resources Information Center

    Lopus, Jane

    1998-01-01

    Reports on interviews conducted with Ukrainian teachers who were asked whether they and others they know are better, or worse, off since Ukrainian independence. Addresses inflation, private enterprise, delayed salaries, and new freedoms. Provides insights into the effects of the transition on people's lives and hopes for the future. (DSK)

  18. Suicide and Mass Urban Transit.

    ERIC Educational Resources Information Center

    Berman, Alan L., Ed.

    1991-01-01

    Presents case consultation in which consultants respond to issues of urban planning for mass transit (subway) system and how to maximize prevention of intentional injury within subway stations. Also asks what type of research study should be used and what type of data collected once system is operating. Case is discussed by Morton M. Silverman and…

  19. Leadership Transitions: Keys for Success

    ERIC Educational Resources Information Center

    Goodyear, Marilu; Golden, Cynthia

    2008-01-01

    A leadership transition poses dangers and challenges for both leaders and followers. While each party naturally focuses on the organization's success, time needs to be spent on how the new relationships will develop and mature into effective working relationships. This article discusses the following four areas of interaction between leaders and…

  20. Women's Work Transitions Around Childbearing

    Microsoft Academic Search

    Jennifer Baxter

    2005-01-01

    There is little known about the extent to which Australian women leave work on commencement of childbearing or return to work afterwards. Of particular interest is whether or not women return to full-time or part-time work. This paper uses work histories collected in Waves 1 and 2 of the Negotiating the Life Course (NLC) Surveys to analyse these transitions for

  1. Characteristic length of glass transition

    NASA Astrophysics Data System (ADS)

    Donth, E.

    1996-03-01

    The characteristic length of the glass transition (? _? ) is based on the concept of cooperatively rearranging regions (CRR's) by Adam & Gibbs (1965): ? _? is the diameter of one CRR. In the theoretical part of the talk a formula is derived how this length can be calculated from calorimetric data of the transformation interval. The approach is based on fluctuations in natural functional subsystems. The corresponding thermodynamics is represented e.g. in a book of the author (E. Donth, Relaxation and Thermodynamics in Polymers. Glass Transition, Akademie-Verlag, Berlin 1992). A typical value for this length is 3 nanometers. In the experimental part several examples are reported to enlarge the experimental evidence for such a length: Squeezing the glass transition in the amorphous layers of partially crystallized PET (C. Schick, Rostock), glass transition of small-molecule glass formers in a series of nanoscaled pores of porous glasses (F. Kremer, Leipzig), comparison with a concentration fluctuation model in homogeneous polymer mixtures (E.W. Fischer, Mainz), and, from our laboratory, backscaling to ? _? across the main transition from the entanglement spacing in several amorphous polymers such as PVAC, PS, NR, and some polymer networks. Rouse backscaling was possible in the ? ? splitting region of several poly(n alkyl methacrylates) resulting in small characteristic lengths of order 1 nanometer near the onset of ? cooperativity. In a speculative outlook a dynamic density pattern is presented, having a cellular structure with higher density and lower mobility of the cell walls. It will be explained, with the aid of different thermal expansion of wall and clusters, how the clusters within the cells maintain a certain mobility far below the glass temperature.

  2. Coastal lagoons: “transitional ecosystems” between transitional and coastal waters

    Microsoft Academic Search

    Angel Pérez-Ruzafa; Concepción Marcos; Isabel María Pérez-Ruzafa; María Pérez-Marcos

    The European Water Framework Directive (WFD) establishes a well differentiated typology of water bodies on the basis of scientific\\u000a and biological criteria. For coastal waters, such criteria have long been established, while for transitional waters they\\u000a are still under discussion. One of the difficulties when applying the WFD to coastal lagoons is to include them in only one\\u000a of these

  3. 44 CFR 19.230 - Transition plans.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false Transition plans. 19...230 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT... § 19.230 Transition plans. (a...class during the period covered by...

  4. Correlations in noisy Landau-Zener transitions

    E-print Network

    Pokrovsky, Valery L.; Scheidl, S.

    2004-01-01

    We analyze the influence of colored classical Gaussian noise on Landau-Zener transitions during a two-level crossing in a time-dependent regular external field. Transition probabilities and coherence factors become random due to the noise. We...

  5. OBSERVATIONAL WINDOW FUNCTIONS IN PLANET TRANSIT SURVEYS

    SciTech Connect

    Von Braun, Kaspar; Kane, Stephen R.; Ciardi, David R. [NASA Exoplanet Science Institute, California Institute of Technology, MC 100-22, Pasadena, CA 91125 (United States)], E-mail: kaspar@ipac.caltech.edu, E-mail: skane@ipac.caltech.edu, E-mail: ciardi@ipac.caltech.edu

    2009-09-01

    The probability that an existing planetary transit is detectable in one's data is sensitively dependent upon the window function of the observations. We quantitatively characterize and provide visualizations of the dependence of this probability as a function of orbital period upon several observing strategy and astrophysical parameters, such as length of observing run, observing cadence, length of night, transit duration and depth, and the minimum number of sampled transits. The ability to detect a transit is directly related to the intrinsic noise of the observations. In our simulations of observational window functions, we explicitly address noncorrelated (Gaussian or white) noise and correlated (red) noise and discuss how these two noise components affect transit detectability in fundamentally different manners, especially for long periods and/or small transit depths. We furthermore discuss the consequence of competing effects on transit detectability, elaborate on measures of observing strategies, and examine the projected efficiency of different transit survey scenarios with respect to certain regions of parameter space.

  6. Recent Transitions in Ethiopian Homegarden Agroforestry: Driving

    E-print Network

    development efforts towards a stable and sustainable land use and gender equity in rural development. ItsRecent Transitions in Ethiopian Homegarden Agroforestry: Driving Forces and Changing Gender Transitions in Ethiopian Homegarden Agroforestry: Driving Forces and Changing Gender Relations Abstract

  7. 5 CFR 362.210 - Transition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...Administration § 362.210 Transition. OPM shall provide written guidance for the orderly transition of employees from the Presidential Management Intern Program to the Fellow program and may revise it as...

  8. Site Transition Plan Guidance, December 2004

    SciTech Connect

    none,

    2004-12-01

    A short Department of Energy program document has been created to provide an outline on what the Site Transition Plan (STP) objectives are for the transition from the Office of Environmental Management to the newly established Office of Legacy Management.

  9. Planets in Transit V Passages of Discovery

    NASA Astrophysics Data System (ADS)

    Castellano, T. P.

    2003-05-01

    Eclipses of the Sun have long influenced culture, history, and science. The analogous but much more subtle phenomena of a transit of the Sun by Mercury was first predicted by Johannes Kepler. Soon, predictions of transits of Venus inspired bold expeditions to better understand the scale of our solar system. These passages of discovery sometimes succeeded scientifically but always captured the public imagination and played an unexpected role in history. The possibility of detecting planets outside the solar system by the transit method was first outlined by Otto Struve in 1952. Early inquiries usually assumed that extrasolar planetary systems would have a distribution of planetary radii and orbital sizes like the solar system. The detection of transits from the ground in such systems would be daunting. The recent, unexpected discovery of a class of extrasolar planets (by the radial velocity technique) with orbital periods less than a week and masses near to the planet Jupiter has resulted in a resurgence of interest in the transit method. These so called "hot Jupiters", can produce transits that are likely enough, frequent enough, the transit method. These so called "hot Jupiters", can produce transits that are likely enough, frequent enough, and deep enough that ground-based transit searches can be successful. In November 1999, a planet orbiting the star HD 209458 was found to transit, and many measurements of the transit have since been made that challenge formation and evolution theories. Numerous ground based searches for transits are now underway. Several planned high precision space-based missions designed to detect transits of earth-sized planets, also have the potential to detect transits of hundreds of "hot Jupiters". These efforts and the upcoming transit of the Sun by Venus on June 8, 2004 present an opportunity for transits to once again capture the public imagination and perhaps play a role in history.

  10. Venus transits - A French view

    NASA Astrophysics Data System (ADS)

    Débarbat, Suzanne

    2005-04-01

    After a careful study of Mars observations obtained by Tycho Brahé (1546-1601), Kepler (1571-1630) discovered the now-called Kepler's third law. In 1627 he published his famous Tabulae Rudolphinae, a homage to his protector Rudolph II (1552-1612), tables (Kepler 1609, 1627) from which he predicted Mercury and Venus transits over the Sun. In 1629 Kepler published his Admonitio ad Astronomos Advertisement to Astronomers (Kepler 1630), Avertissement aux Astronomes in French Au sujet de phénomènes rares et étonnants de l'an 1631: l'incursion de Vénus et de Mercure sur le Soleil. This was the beginning of the interest of French astronomers, among many others, in such transits, mostly for Venus, the subject of this paper in which dates are given in the Gregorian calendar.

  11. A Kepler Transiting Circumbinary Planet

    NASA Astrophysics Data System (ADS)

    Welsh, William F.; Orosz, J. A.; Fabrycky, D. C.; Haghighipour, N.; Short, D. R.; Kepler Team

    2014-01-01

    Among the thousands of planet candidates discovered by Kepler only a few have been detected in binary star systems. To date, seven transiting circumbinary planets have been confirmed, with several more candidates planets under investigation. Of the confirmed cases, the planets orbit short-period eclipsing binaries that have periods between one and seven weeks. The eclipsing binary nature of the stars allows their masses and radii to be accurately determined. Perturbations of the binary can be detected by eclipsing timing variations, sometimes allowing the mass of the planet to be measured. In this talk, we present the most recent Kepler transiting circumbinary planet. We gratefully acknowledge support from the NSF via grant AST-1109928, and from NASA via Kepler PSP grant NNX12AS23G and OSS grant NNX12AI76G.

  12. Phase transitions in wave turbulence.

    PubMed

    Vladimirova, Natalia; Derevyanko, Stanislav; Falkovich, Gregory

    2012-01-01

    We consider turbulence within the Gross-Pitaevsky model and look into the creation of a coherent condensate via an inverse cascade originating at small scales. The growth of the condensate leads to a spontaneous breakdown of statistical symmetries of overcondensate fluctuations: First, isotropy is broken, then a series of phase transitions marks the changing symmetry from twofold to threefold to fourfold. We describe respective anisotropic flux flows in the k space. At the highest level reached, we observe a short-range positional and long-range orientational order (as in a hexatic phase). In other words, the more one pumps the system, the more ordered the system becomes. The phase transitions happen when the system is pumped by an instability term and does not occur when pumped by a random force. We thus demonstrate nonuniversality of an inverse-cascade turbulence with respect to the nature of small-scale forcing. PMID:22400497

  13. Electronic transitions of palladium dimer

    SciTech Connect

    Qian, Yue; Ng, Y. W.; Chen, Zhihua; Cheung, A. S.-C., E-mail: hrsccsc@hku.hk [Department of Chemistry, The University of Hong Kong, Pokfulam Road (Hong Kong)

    2013-11-21

    The laser induced fluorescence spectrum of palladium dimer (Pd{sub 2}) in the visible region between 480 and 700 nm has been observed and analyzed. The gas-phase Pd{sub 2} molecule was produced by laser ablation of palladium metal rod. Eleven vibrational bands were observed and assigned to the [17.1] {sup 3}II{sub g} - X{sup 3}?{sub u}{sup +} transition system. The bond length (r{sub o}) and vibrational frequency (?G{sub 1/2}) of the ground X{sup 3}?{sub u}{sup +} state were determined to be 2.47(4) Å and 211.4(5) cm{sup ?1}, respectively. A molecular orbital energy level diagram was used to understand the observed ground and excited electronic states. This is the first gas-phase experimental investigation of the electronic transitions of Pd{sub 2}.

  14. Structural transitions in liquid cesium

    NASA Astrophysics Data System (ADS)

    Belashchenko, D. K.

    2014-09-01

    Two series of models of liquid cesium at temperatures of 493 and 623 K and pressures lower than 18 GPa are constructed by means of molecular dynamics using the potential of the embedded atom model. The thermodynamic properties of the models, pair correlation functions, pair radial distribution functions, structure factors, coordination numbers, and distributions of the Voronoi polyhedra and Delaunay simplexes are analyzed. No indications of structural transitions in liquid cesium of the first-order phase transition type are observed near a pressure of 3.9 GPa. Divergences from the results of some X-ray diffraction studies could be due to incorrect determination of the coordination numbers via the standard method because of the strong asymmetry of the first peaks of the pair radial distribution functions.

  15. Holographic Roberge-Weiss Transitions

    E-print Network

    Gert Aarts; S. Prem Kumar; James Rafferty

    2010-07-15

    We investigate N=4 SYM coupled to fundamental flavours at nonzero imaginary quark chemical potential in the strong coupling and large N limit, using gauge/gravity duality applied to the D3-D7 system, treating flavours in the probe approximation. The interplay between Z(N) symmetry and the imaginary chemical potential yields a series of first-order Roberge-Weiss transitions. An additional thermal transition separates phases where quarks are bound/unbound into mesons. This results in a set of Roberge-Weiss endpoints: we establish that these are triple points, determine the Roberge-Weiss temperature, give the curvature of the phase boundaries and confirm that the theory is analytic in mu^2 when mu^2~0.

  16. Electronic Transitions of Yttrium Monoxide

    NASA Astrophysics Data System (ADS)

    Ng, Y. W.; Wang, Na; Clark, Andrew B.; Cheung, A. S.-C.

    2013-06-01

    The electronic transition spectrum of yttrium monoxide (YO) in the spectral region between 284nm and 307nm has been recorded using laser ablation/reaction free-jet expansion and laser induced fluorescence (LIF) spectroscopy. The YO molecule was produced by reacting laser-ablated yttrium atoms with O_{2} seeded in argon. Twenty transition bands were observed in that region and a few bands were selected for further study using optical-optical double resonance (OODR) spectroscopy. The excited C^{2} ? state has been reached via the intermediate B^{2} ?^{+} state from the ground X^{2} ?^{+} state. The excited sub-states observed so far have ? = 0.5 and 1.5. A least squares fit of the measured rotational lines yielded molecular constants for the newly observed excited states.

  17. A Latent Transition Model with Logistic Regression

    ERIC Educational Resources Information Center

    Chung, Hwan; Walls, Theodore A.; Park, Yousung

    2007-01-01

    Latent transition models increasingly include covariates that predict prevalence of latent classes at a given time or transition rates among classes over time. In many situations, the covariate of interest may be latent. This paper describes an approach for handling both manifest and latent covariates in a latent transition model. A Bayesian…

  18. Electrical Dissipation Measurement of Polymer Phase Transitions

    NASA Technical Reports Server (NTRS)

    Long, E. R., R; Schuszler, A., II

    1983-01-01

    Technique measures solid/solid, glass/rubber, and liquid/liquid transition temperatures in polymers having dipole moments. Technique based on change in dipole packing that occurs with each transition and measured as change in electrical dissipation factor. Change in dipole packing occuring with each transition sensed by effect on dissipation factor.

  19. Student Life Veterans Education and Transition Services

    E-print Network

    Thomas, Andrew

    Student Life Veterans Education and Transition Services Veterans Services #12;The UMaine VETS Office (Veterans Education and Transition Services) works in every way possible to make the transition from military to student life simple and hassle-free. Our Mission: The VETS Office connects veteran

  20. Running Head: TRANSITION PLANNING SYSTEMATIC REVIEW

    Microsoft Academic Search

    Brian Cobb; Morgen Alwell

    Abstract The relationship between transition planning\\/coordinating interventions and transition outcomes for secondary aged youth with disabilities was explored in this systematic review. A total of 31 studies intervening with 859 youth with a wide variety of disabilities were reviewed. Using the transition intervention framework,of Kohler and Field (2003) the findings of this review support the efficacy of student focused planning

  1. A Smoother Transition for Black Teens

    ERIC Educational Resources Information Center

    Holcomb-McCoy, Cheryl

    2011-01-01

    For all students, the transition to high school may lead to lower academic achievement and adjustment problems. Black students are at greater risk for academic and social decline during this transition. Holcomb-McCoy identifies four obstacles that make black students more vulnerable as they navigate the transition into high school: stereotyping in…

  2. PORCUPINE-LIKE HORSESHOES: TRANSITIVITY, LYAPUNOV SPECTRUM,

    E-print Network

    Díaz, Lorenzo J.

    PORCUPINE-LIKE HORSESHOES: TRANSITIVITY, LYAPUNOV SPECTRUM, AND PHASE TRANSITIONS LORENZO J. D homoclinic classes 4 2. Examples of porcupine-like homoclinic classes 8 3. One-dimensional central dynamics provide examples of non-hyperbolic transitive sets, that we call porcupine-like horseshoes or, briefly

  3. 9 CFR 332.12 - Transition grants.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Transition grants. 332.12 Section 332.12 Animals and Animal Products FOOD SAFETY AND...PARTS OF CARCASSES, MEAT, AND MEAT FOOD PRODUCTS § 332.12 Transition grants. (a) Transition...

  4. 9 CFR 332.12 - Transition grants.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Transition grants. 332.12 Section 332.12 Animals and Animal Products FOOD SAFETY AND...PARTS OF CARCASSES, MEAT, AND MEAT FOOD PRODUCTS § 332.12 Transition grants. (a) Transition...

  5. Evidence-Based Practices in Secondary Transition

    ERIC Educational Resources Information Center

    Test, David W.; Fowler, Catherine H.; Richter, Sharon M.; White, James; Mazzotti, Valerie; Walker, Allison R.; Kohler, Paula; Kortering, Larry

    2009-01-01

    A literature review was conducted to identify evidence-based practices in secondary transition using quality indicator checklists for experimental research. Practices were categorized by the Taxonomy for Transition Programming. Overall, 32 secondary transition evidence-based practices were identified. Two practices had a strong level of evidence,…

  6. Vulnerable Youth and Transitions to Adulthood

    ERIC Educational Resources Information Center

    Xie, Rongbing; Sen, Bisakha; Foster, E. Michael

    2014-01-01

    This chapter focuses on vulnerable youth, the challenges they face during their transitions to adulthood, and the adverse effects of limited support systems on those transitions. The authors offer recommendations on how adult educators can help facilitate smooth transitions into adulthood for vulnerable youth.

  7. Maintenance Staffing Levels for Light Rail Transit

    Microsoft Academic Search

    Richard Stanger

    2005-01-01

    This synthesis documents light rail maintenance staffing practices and factors important in their development at U.S. transit agencies. It covers the areas of maintenance functions, new light rail start-up, and management in attempting to give better insight into the variables affecting maintenance staffing. This topic is of interest to transit managers of existing light rail transit (LRT) operations and those

  8. Fluor Hanford (FH) River Corridor Transition Plan

    SciTech Connect

    MCBRIDE, D.J.

    2002-08-28

    This Transition Plan defines the scope and schedule for actions that are critical for a smooth transition of the River Corridor scope of work and to ensure the achievement of transition as planned, with minimal or no impact to ongoing baseline activities.

  9. Teaching Mainstreamed Children to Manage Daily Transitions.

    ERIC Educational Resources Information Center

    Rosenkoetter, Sharon E.; Fowler, Susan A.

    1986-01-01

    Based on a study of the differences between the way regular and special education teachers handle classroom transitions, this discussion suggests seven steps special education teachers should take to aid students in classroom transitions. A list of 24 different transition cues is included. (JC)

  10. Chloroplast transit peptides: structure, function and evolution

    Microsoft Academic Search

    Barry D. Bruce

    2000-01-01

    It is thought that two to three thousand different proteins are targeted to the chloroplast, and the ‘transit peptides’ that act as chloroplast targeting sequences are probably the largest class of targeting sequences in plants. At a primary structural level, transit peptide sequences are highly divergent in length, composition and organization. An emerging concept suggests that transit peptides contain multiple

  11. Budapest's built environment in transition

    Microsoft Academic Search

    Alan Dingsdale

    1999-01-01

    The construction of major new buildings has been noticed in Budapest since the mid 1980s. New hotels, office blocks, housing\\u000a projects and most recently shopping centres have become a prominent feature of the landscape in several districts of the city.\\u000a The paper first outlines a conceptualisation of the `Transition' in terms of eastern Europe as a whole identifying internationalisation,\\u000a Europeanisation

  12. SHG on Transition Metal Oxides

    Microsoft Academic Search

    O. Ney

    2005-01-01

    Optical second harmonic generation (SHG), within the electric-dipole approximation, is known to be sensitive to the surface electronic structure of inversion symmetric media. Besides, it allows to distinguish magneto-optically ferromagnetic from antiferromagnetic order of cubic (001) surfaces. Here, we compute the SHG from NiO(001) and CoO(001) surfaces from first principles. To address the notoriously difficult electronic correlations of transition metal

  13. Venus transits - A French view

    Microsoft Academic Search

    Suzanne Débarbat

    2005-01-01

    After a careful study of Mars observations obtained by Tycho Brahé (1546-1601), Kepler (1571-1630) discovered the now-called Kepler's third law. In 1627 he published his famous Tabulae Rudolphinae, a homage to his protector Rudolph II (1552-1612), tables (Kepler 1609, 1627) from which he predicted Mercury and Venus transits over the Sun. In 1629 Kepler published his Admonitio ad Astronomos Advertisement

  14. Phase transitions in nuclear matter

    SciTech Connect

    Glendenning, N.K.

    1984-11-01

    The rather general circumstances under which a phase transition in hadronic matter at finite temperature to an abnormal phase in which baryon effective masses become small and in which copious baryon-antibaryon pairs appear is emphasized. A preview is also given of a soliton model of dense matter, in which at a density of about seven times nuclear density, matter ceases to be a color insulator and becomes increasingly color conducting. 22 references.

  15. The ALICE transition radiation detector

    Microsoft Academic Search

    Tariq Mahmoud

    2003-01-01

    The ALICE Transition Radiation Detector (TRD) is equipped with 750m2 total area of gas chambers with radiators for particle tracking and electron identification above 1GeV\\/c, divided in 540 modules organized in 18 sectors and 6 layers, in a barrel geometry between 2.9 and 3.7m from the beam axis. The TRD will also serve as a trigger on high-pte+e- pairs in

  16. Transiting Exoplanet Survey Satellite (TESS)

    NASA Astrophysics Data System (ADS)

    Ricker, George R.; Winn, Joshua N.; Vanderspek, Roland; Latham, David W.; Bakos, Gáspár. Á.; Bean, Jacob L.; Berta-Thompson, Zachory K.; Brown, Timothy M.; Buchhave, Lars; Butler, Nathaniel R.; Butler, R. Paul; Chaplin, William J.; Charbonneau, David; Christensen-Dalsgaard, Jørgen; Clampin, Mark; Deming, Drake; Doty, John; De Lee, Nathan; Dressing, Courtney; Dunham, E. W.; Endl, Michael; Fressin, Francois; Ge, Jian; Henning, Thomas; Holman, Matthew J.; Howard, Andrew W.; Ida, Shigeru; Jenkins, Jon; Jernigan, Garrett; Johnson, John A.; Kaltenegger, Lisa; Kawai, Nobuyuki; Kjeldsen, Hans; Laughlin, Gregory; Levine, Alan M.; Lin, Douglas; Lissauer, Jack J.; MacQueen, Phillip; Marcy, Geoffrey; McCullough, P. R.; Morton, Timothy D.; Narita, Norio; Paegert, Martin; Palle, Enric; Pepe, Francesco; Pepper, Joshua; Quirrenbach, Andreas; Rinehart, S. A.; Sasselov, Dimitar; Sato, Bun'ei; Seager, Sara; Sozzetti, Alessandro; Stassun, Keivan G.; Sullivan, Peter; Szentgyorgyi, Andrew; Torres, Guillermo; Udry, Stephane; Villasenor, Joel

    2014-08-01

    The Transiting Exoplanet Survey Satellite (TESS ) will search for planets transiting bright and nearby stars. TESS has been selected by NASA for launch in 2017 as an Astrophysics Explorer mission. The spacecraft will be placed into a highly elliptical 13.7-day orbit around the Earth. During its two-year mission, TESS will employ four wide-field optical CCD cameras to monitor at least 200,000 main-sequence dwarf stars with IC (approximately less than) 13 for temporary drops in brightness caused by planetary transits. Each star will be observed for an interval ranging from one month to one year, depending mainly on the star's ecliptic latitude. The longest observing intervals will be for stars near the ecliptic poles, which are the optimal locations for follow-up observations with the James Webb Space Telescope. Brightness measurements of preselected target stars will be recorded every 2 min, and full frame images will be recorded every 30 min. TESS stars will be 10-100 times brighter than those surveyed by the pioneering Kepler mission. This will make TESS planets easier to characterize with follow-up observations. TESS is expected to find more than a thousand planets smaller than Neptune, including dozens that are comparable in size to the Earth. Public data releases will occur every four months, inviting immediate community-wide efforts to study the new planets. The TESS legacy will be a catalog of the nearest and brightest stars hosting transiting planets, which will endure as highly favorable targets for detailed investigations.

  17. Transition Radiation Detector in MACRO

    Microsoft Academic Search

    M. N. Mazziotta

    1999-01-01

    The MACRO detector is located in the Gran Sasso Laboratory. MACRO's\\u000aoverburden varies from 3150 to 7000 hg\\/cm^2. A transition radiation detector\\u000a(TRD) has been added to the MACRO detector in order to measure the residual\\u000aenergy of muons entering MACRO, i.e. the energy they have after passing through\\u000athe Gran Sasso's rock overburden. The TRD consists of three identical

  18. Superconductor having variable transition temperature

    Microsoft Academic Search

    G. A. Spiering; E. Revolinsky; D. J. Beerntsen

    1967-01-01

    A superconducting alloy having the general formula Nb(Se\\/sub 2-x\\/N\\/sub x\\/) where N is either sulfur or tellurium and x is a number less than 0.7. The element N, here being an anion, thus occupies selenium lattice sites. The transition temperature of the alloy is inversely proportional to the amount of sulfur or tellurium at a value between 2.0 and 7.0°K.

  19. Transition physics and scaling overview

    SciTech Connect

    Carlstrom, T.N.

    1995-12-01

    This paper presents an overview of recent experimental progress towards understanding H-mode transition physics and scaling. Terminology and techniques for studying H-mode are reviewed and discussed. The model of shear E x B flow stabilization of edge fluctuations at the L-H transition is gaining wide acceptance and is further supported by observations of edge rotation on a number of new devices. Observations of poloidal asymmetries of edge fluctuations and dephasing of density and potential fluctuations after the transition pose interesting challenges for understanding H-mode physics. Dedicated scans to determine the scaling of the power threshold have now been performed on many machines. A dear B{sub t} dependence is universally observed but dependence on the line averaged density is complicated. Other dependencies are also reported. Studies of the effect of neutrals and error fields on the power threshold are under investigation. The ITER threshold database has matured and offers guidance to the power threshold scaling issues relevant to next-step devices.

  20. Trust transitivity in social networks.

    PubMed

    Richters, Oliver; Peixoto, Tiago P

    2011-01-01

    Non-centralized recommendation-based decision making is a central feature of several social and technological processes, such as market dynamics, peer-to-peer file-sharing and the web of trust of digital certification. We investigate the properties of trust propagation on networks, based on a simple metric of trust transitivity. We investigate analytically the percolation properties of trust transitivity in random networks with arbitrary in/out-degree distributions, and compare with numerical realizations. We find that the existence of a non-zero fraction of absolute trust (i.e. entirely confident trust) is a requirement for the viability of global trust propagation in large systems: The average pair-wise trust is marked by a discontinuous transition at a specific fraction of absolute trust, below which it vanishes. Furthermore, we perform an extensive analysis of the Pretty Good Privacy (PGP) web of trust, in view of the concepts introduced. We compare different scenarios of trust distribution: community- and authority-centered. We find that these scenarios lead to sharply different patterns of trust propagation, due to the segregation of authority hubs and densely-connected communities. While the authority-centered scenario is more efficient, and leads to higher average trust values, it favours weakly-connected "fringe" nodes, which are directly trusted by authorities. The community-centered scheme, on the other hand, favours nodes with intermediate in/out-degrees, in detriment of the authorities and its "fringe" peers. PMID:21483683

  1. Pressure-Induced Electronic Phase Transitions Transition Metal Oxides and Rare Earth Metals

    E-print Network

    Islam, M. Saif

    Pressure-Induced Electronic Phase Transitions in Transition Metal Oxides and Rare Earth Metals Metal Oxides and Rare Earth Metals by Brian Ross Maddox Electron correlation can affect profound changes transition in a transition metal monoxide. iv #12;The lanthanides (the 4f metals also known as rare-earths

  2. Transition

    E-print Network

    Welling, Lois

    1982-01-01

    a way. After what I have done, my own will to survive is low, but if there is a way to escape . . If I am to help, I will have to align with her, draw on her strength until I can renew my own. I will have to trust. To depend on her. I cannot do.... Susan and Thela talk, argue, speculate. Soy-an has little to contribute. I remain aloof, watching ... I realize what this news means. What conclusions will they draw? They understand . . . Long-term commitment. They agree that it is the only way. Any...

  3. Energetic Transitions of Magnetic Vortices

    NASA Astrophysics Data System (ADS)

    Burgess, Jacob A. J.

    The vortex state in a magnetic disk contains a zero-dimensional domain wall, and consequently, is a system of interest for the study of fundamental physics. In particular, the disk geometry presents a prototypical system to study the properties of vortex states and to construct proof-of-concept magnetic logic devices. Here, work was performed to elevate the understanding of this system so that device development and experiments may be performed in a truly quantitative fashion. In order to achieve this, hysteretic transitions of the vortex state in thin-film magnetic disks were studied using a variety of techniques. The annihilation transition and its statistics arising from thermal dynamics were studied using a novel tool, AC magneto-optical Kerr effect susceptometry, that permits rapid acquisition of transition statistics. Much smaller hysteretic transitions were studied using extremely sensitive torsional magnetometry. Strong interactions between the core of the vortex and inhomogeneities in the thin-film were studied in 1D and 2D. The bistable states participating in hysteresis were found to exhibit low speed stochastic dynamics that allowed quantitative analysis of transition barriers. To aid in this work an improved analytical model describing the evolution of the vortex state with applied field was developed. In particular this model was demonstrated to be capable of correctly accounting for both the non-monotonic evolution of the magnetization and the vortex core position of the vortex state under a changing magnetic field in the presence of a pinning site. The combination of the model with the torsional magnetometer creates a powerful scanning vortex probe microscope, capable of imaging the energy landscape of the disk with a high spatial resolution. Concurrently, a time-resolved STM equipped with spin polarized tips was successfully constructed, and applied to study in situ fabricated patterned magnetic disks. This attempt to observe magneto-dynamics on an unprecedented combination of spatial and temporal scales has not yet provided results, as magnetic contrast remains elusive. In developing novel high speed STM samples, cluster dynamics were discovered and studied in a metallic glass. In addition to equilibrium dynamics, the formation of a surface state of large clusters was directly observed as the film aged.

  4. Protein dynamical transition at 110 K

    PubMed Central

    Kim, Chae Un; Tate, Mark W.; Gruner, Sol M.

    2011-01-01

    Proteins are known to undergo a dynamical transition at around 200 K but the underlying mechanism, physical origin, and relationship to water are controversial. Here we report an observation of a protein dynamical transition as low as 110 K. This unexpected protein dynamical transition precisely correlated with the cryogenic phase transition of water from a high-density amorphous to a low-density amorphous state. The results suggest that the cryogenic protein dynamical transition might be directly related to the two liquid forms of water proposed at cryogenic temperatures. PMID:22167801

  5. Work and quantum phase transitions: quantum latency.

    PubMed

    Mascarenhas, E; Bragança, H; Dorner, R; França Santos, M; Vedral, V; Modi, K; Goold, J

    2014-06-01

    We study the physics of quantum phase transitions from the perspective of nonequilibrium thermodynamics. For first-order quantum phase transitions, we find that the average work done per quench in crossing the critical point is discontinuous. This leads us to introduce the quantum latent work in analogy with the classical latent heat of first order classical phase transitions. For second order quantum phase transitions the irreversible work is closely related to the fidelity susceptibility for weak sudden quenches of the system Hamiltonian. We demonstrate our ideas with numerical simulations of first, second, and infinite order phase transitions in various spin chain models. PMID:25019721

  6. Partially resolved super transition array method

    NASA Astrophysics Data System (ADS)

    Wilson, Brian G.; Iglesias, Carlos A.; Chen, Mau H.

    2015-03-01

    The partially resolved transition array model for radiative transitions between ordinary electronic configurations is extended to the super configuration approach. The specific application incorporates intermediate coupling effects into transition arrays to describe the transition from LS to JJ coupling without the ad hoc approximations introduced in past formulations. More generally, the extended concept permits stepwise refinement of the super transition array method towards the line-by-line limit in ordinary configurations. Thus, the formalism forms a framework for a hybrid scheme to combine detailed line accounting and statistical methods.

  7. Volume Collapse Transitions in Transition Metals and Compounds at High Pressures

    Microsoft Academic Search

    Choong-Shik Yoo; B. Maddox; M. Hu; P. Chow; V. Iota; B. Baer; W. Evans; H. Cynn; D. Hausermann

    2004-01-01

    Unusual phase transitions driven by electron correlation effects occur in many transition metals and transition metal compounds at high pressures, some accompanied with large volume collapses (5-17% in rare-earth metals and 10-15% in magnetic 3d transition metal oxides, for example). However, the exact nature of these transitions has not been well understood, including the relationships between the crystal and electronic

  8. Energy Landscape of Zirconia Phase Transitions.

    PubMed

    Guan, Shu-Hui; Zhang, Xiao-Jie; Liu, Zhi-Pan

    2015-07-01

    The solid-phase transitions of zirconia are important phenomena for many industrial applications. Because of the lack of tools for resolving the atom displacement pattern, the transition kinetics has been disputed for over 60 years. Here, first-principles-based stochastic surface walking (SSW) pathway sampling is utilized for resolving the mechanism of ZrO2 tetragonal-to-monoclinic solid-phase transition. Two types of lattice and atom correspondence allowed in phase transition are determined for the first time from energy criterion, which are originated from two nearly energy-degenerate lowest-transition pathways and one stress-induced ferroelastic transition channel of tetragonal phase. An orthorhombic crystal phase (Pbc2/1) is discovered to be a trapping state at low temperatures in phase transition, the presence of which does not create new orientation relation but deters transformation toughening significantly. This new finding may facilitate the design of new functional oxide materials in ceramic industry. PMID:26075311

  9. Transitional Care Strategies From Hospital to Home

    PubMed Central

    Ranji, Sumant R.

    2015-01-01

    Hospitals are challenged with reevaluating their hospital’s transitional care practices, to reduce 30-day readmission rates, prevent adverse events, and ensure a safe transition of patients from hospital to home. Despite the increasing attention to transitional care, there are few published studies that have shown significant reductions in readmission rates, particularly for patients with stroke and other neurologic diagnoses. Successful hospital-initiated transitional care programs include a “bridging” strategy with both predischarge and postdischarge interventions and dedicated transitions provider involved at multiple points in time. Although multicomponent strategies including patient engagement, use of a dedicated transition provider, and facilitation of communication with outpatient providers require time and resources, there is evidence that neurohospitalists can implement a transitional care program with the aim of improving patient safety across the continuum of care. PMID:25553228

  10. Metal to semiconductor transition in metallic transition metal dichalcogenides

    SciTech Connect

    Li, Yan; Kang, Jun; Li, Jingbo, E-mail: jbli@semi.ac.cn [State Key Laboratory of Superlattice and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China); Tongay, Sefaattin; Wu, Junqiao [Department of Materials Science and Engineering, University of California, Berkeley, California 94720 (United States); Yue, Qu [College of Science, National University of Defense Technology, Changsha 410073 (China)

    2013-11-07

    We report on tuning the electronic and magnetic properties of metallic transition metal dichalcogenides (mTMDCs) by 2D to 1D size confinement. The stability of the mTMDC monolayers and nanoribbons is demonstrated by the larger binding energy compared to the experimentally available semiconducting TMDCs. The 2D MX{sub 2} (M?=?Nb, Ta; X?=?S, Se) monolayers are non-ferromagnetic metals and mechanically softer compared to their semiconducting TMDCs counterparts. Interestingly, mTMDCs undergo metal-to-semiconductor transition when the ribbon width approaches to ?13?Å and ?7?Å for zigzag and armchair edge terminations, respectively; then these ribbons convert back to metal when the ribbon widths further decrease. Zigzag terminated nanoribbons are ferromagnetic semiconductors, and their magnetic properties can also be tuned by hydrogen edge passivation, whereas the armchair nanoribbons are non-ferromagnetic semiconductors. Our results display that the mTMDCs offer a broad range of physical properties spanning from metallic to semiconducting and non-ferromagnetic to ferromagnetic that is ideal for applications where stable narrow bandgap semiconductors with different magnetic properties are desired.

  11. Transition splices and cost comparison

    NASA Technical Reports Server (NTRS)

    Remedios, M. D.

    1972-01-01

    The development and testing of two designs of transition splices are reported. The design goal was to produce splice terminations that are electrically insulated to withstand the environmental conditions of commercial aircraft and are capable of being repaired and reworked on installed cables with the use of hand tools. In addition, a cost study comparison of FCC vs. RCC is reported. The comparison was made on a basis of 10 aircraft with each vehicle using approximately 100,000 feet of wiring and 2,000 connectors. The results are tabulated for seven different wiring configurations.

  12. Shim for sealing transition pieces

    DOEpatents

    Lacy, Benjamin Paul (Greer, SC); Demiroglu, Mehmet (Troy, NY); Sarawate, Neelesh Nandkumar (Niskayuna, NY)

    2012-07-24

    According to one aspect of the invention, a shim for sealing two adjacent turbine transition pieces is disclosed. The shim includes a circumferential member that includes a first lateral flange and a second lateral flange. Further, the first and second lateral flanges each comprise a tab configured to mate to a first surface plane and the first and second lateral flanges are configured to mate to a second surface plane, wherein the first and second surface planes are substantially parallel. In addition, the shim includes a first flange extending substantially perpendicular from the circumferential member.

  13. Fluctuations and Phase Transition Dynamics

    E-print Network

    Rivers, R J

    2000-01-01

    Kibble and Zurek have provided a unifying causal picture for the appearance of classical defects like cosmic strings or vortices at the onset of phase transitions in relativistic QFT and condensed matter systems respectively. In condensed matter the predictions are partially supported by agreement with experiments in superfluid helium. We provide an alternative picture for the initial appearance of defects that supports the experimental evidence. When the original predictions fail, this is understood, in part, as a consequence of thermal fluctuations (noise), which play a comparable role in both condensed matter and QFT.

  14. Feeding the Transition Dairy Cow 

    E-print Network

    Stokes, Sandra R.

    1999-09-20

    available forages for the dry cows are high in calcium, phospho- rus, and/or potassium. Anionic salts are fed to manipulate the dietary cation/ anion balance in the close-up cow. These L-5197 8-99 Feeding the transition dairy cow Sandra R. Stokes* *Extension... dairy specialist; The Texas A&M University System. Feed intake usually decreases in the f_inal week before calving T salts lower body pH and stimulate calci- um release from the bones and calcium absorption from the gut. However, these salts are not very...

  15. Stellar Transits in Active Galactic Nuclei

    NASA Astrophysics Data System (ADS)

    Béky, Bence; Kocsis, Bence

    2013-01-01

    Supermassive black holes (SMBHs) are typically surrounded by a dense stellar population in galactic nuclei. Stars crossing the line of site in active galactic nuclei (AGNs) produce a characteristic transit light curve, just like extrasolar planets do when they transit their host star. We examine the possibility of finding such AGN transits in deep optical, UV, and X-ray surveys. We calculate transit light curves using the Novikov-Thorne thin accretion disk model, including general relativistic effects. Based on the expected properties of stellar cusps, we find that around 106 solar mass SMBHs, transits of red giants are most common for stars on close orbits with transit durations of a few weeks and orbital periods of a few years. We find that detecting AGN transits requires repeated observations of thousands of low-mass AGNs to 1% photometric accuracy in optical, or ~10% in UV bands or soft X-ray. It may be possible to identify stellar transits in the Pan-STARRS and LSST optical and the eROSITA X-ray surveys. Such observations could be used to constrain black hole mass, spin, inclination, and accretion rate. Transit rates and durations could give valuable information on the circumnuclear stellar clusters as well. Transit light curves could be used to image accretion disks with unprecedented resolution, allowing us to resolve the SMBH silhouette in distant AGNs.

  16. STELLAR TRANSITS IN ACTIVE GALACTIC NUCLEI

    SciTech Connect

    Beky, Bence [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)] [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Kocsis, Bence, E-mail: bbeky@cfa.harvard.edu, E-mail: bkocsis@cfa.harvard.edu

    2013-01-01

    Supermassive black holes (SMBHs) are typically surrounded by a dense stellar population in galactic nuclei. Stars crossing the line of site in active galactic nuclei (AGNs) produce a characteristic transit light curve, just like extrasolar planets do when they transit their host star. We examine the possibility of finding such AGN transits in deep optical, UV, and X-ray surveys. We calculate transit light curves using the Novikov-Thorne thin accretion disk model, including general relativistic effects. Based on the expected properties of stellar cusps, we find that around 10{sup 6} solar mass SMBHs, transits of red giants are most common for stars on close orbits with transit durations of a few weeks and orbital periods of a few years. We find that detecting AGN transits requires repeated observations of thousands of low-mass AGNs to 1% photometric accuracy in optical, or {approx}10% in UV bands or soft X-ray. It may be possible to identify stellar transits in the Pan-STARRS and LSST optical and the eROSITA X-ray surveys. Such observations could be used to constrain black hole mass, spin, inclination, and accretion rate. Transit rates and durations could give valuable information on the circumnuclear stellar clusters as well. Transit light curves could be used to image accretion disks with unprecedented resolution, allowing us to resolve the SMBH silhouette in distant AGNs.

  17. THE QUASIPERIODIC AUTOMATED TRANSIT SEARCH ALGORITHM

    SciTech Connect

    Carter, Joshua A. [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Agol, Eric [Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195 (United States)

    2013-03-10

    We present a new algorithm for detecting transiting extrasolar planets in time-series photometry. The Quasiperiodic Automated Transit Search (QATS) algorithm relaxes the usual assumption of strictly periodic transits by permitting a variable, but bounded, interval between successive transits. We show that this method is capable of detecting transiting planets with significant transit timing variations without any loss of significance-{sup s}mearing{sup -}as would be incurred with traditional algorithms; however, this is at the cost of a slightly increased stochastic background. The approximate times of transit are standard products of the QATS search. Despite the increased flexibility, we show that QATS has a run-time complexity that is comparable to traditional search codes and is comparably easy to implement. QATS is applicable to data having a nearly uninterrupted, uniform cadence and is therefore well suited to the modern class of space-based transit searches (e.g., Kepler, CoRoT). Applications of QATS include transiting planets in dynamically active multi-planet systems and transiting planets in stellar binary systems.

  18. Elaborating transition interface sampling methods

    SciTech Connect

    Erp, Titus S. van [Laboratoire de Physique/Centre Europeen de Calcul Atomique et Moleculaire, Ecole Normale Superieure de Lyon, 46 allee d'Italie, 69364 Lyon Cedex 07 (France)]. E-mail: tsvanerp@cecam.fr; Bolhuis, Peter G. [Van't Hoff Institute for Molecular Sciences, Universiteit van Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam (Netherlands)]. E-mail: bolhuis@science.uva.nl

    2005-05-01

    We review two recently developed efficient methods for calculating rate constants of processes dominated by rare events in high-dimensional complex systems. The first is transition interface sampling (TIS), based on the measurement of effective fluxes through hypersurfaces in phase space. TIS improves efficiency with respect to standard transition path sampling (TPS) rate constant techniques, because it allows a variable path length and is less sensitive to recrossings. The second method is the partial path version of TIS. Developed for diffusive processes, it exploits the loss of long time correlation. We discuss the relation between the new techniques and the standard reactive flux methods in detail. Path sampling algorithms can suffer from ergodicity problems, and we introduce several new techniques to alleviate these problems, notably path swapping, stochastic configurational bias Monte Carlo shooting moves and order-parameter free path sampling. In addition, we give algorithms to calculate other interesting properties from path ensembles besides rate constants, such as activation energies and reaction mechanisms.

  19. Nutrition transition and food sustainability.

    PubMed

    Belahsen, Rekia

    2014-08-01

    The aim of the present paper is to review nutrition transition (NT) ongoing in low and middle income countries and the associated dietary changes. NT is accompanied by demographic and epidemiological transition associated with economic development and urbanisation. In these countries, while the problems of hunger and undernourishment persist, there is an escalation of diet-related non-communicable diseases; making them face both problems of malnutrition, under and overnutrition. Indeed, in addition to protein energy malnutrition underweight and micronutrient deficiencies affect a high proportion of children and women. Conversely, changes in dietary habits and physical activity patterns have led to emergence of chronic diseases such as obesity, diabetes, hypertension, stroke, hyperlipidaemia, CHD and cancer. One possible explanation of weight gain and its associated health consequences is the trend of the consumption of already prepared meals and the restaurants that are in continuous development leading to high consumption of foods rich in sugar and fat. The health problems associated with NT have not spared populations in the Mediterranean area where the type of diet is reported to be healthy and to protect against cardiovascular risks. This is seen in North Africa that belongs also to the Mediterranean basin, where the nutritional situation raises the problem of traditional foods sustainability. Accurate nutritional policy and education are needed to redress the effects of malnutrition related to NT on health. PMID:24824339

  20. The nurse manager in transition.

    PubMed

    Davidhizar, Ruth; Shearer, Ruth

    2003-01-01

    With the current, widespread, highly visible, non-fault dismissals brought about by massive hospital downsizing and restructuring, there has been a layoff of many capable, responsible, and respectable managers. In some localities it will not be possible to obtain a similar position to the one that is lost. Adjusting to this significant life transition event, moving from one job to another involves a process that is initiated when the manager's current reality is disrupted and ends when a bridge is built from the disrupted reality to one of the possible realities that can be created. During this process there are many emotional ups and downs and confusion as to identity. While what is happening may be clear to an observer, for the person in transition reality may be fractured in such a devastating way that it is like being frozen in time. Finally, a new reality is built as the old one is relinquished, and the excitement of new beginnings is experienced with a new and perhaps different role. Eventually, the pain and disappointment of losing a job is replaced with the challenges of the present. Meanwhile, while the present job seems secure it is good planning for the future to be aware and ready for the job hunt process. Getting laid off or fired is a real possibility in today's tightening economic conditions and the astute nurse manager should be ready for it. PMID:14694753

  1. Dynamic transition in supercritical iron.

    PubMed

    Fomin, Yu D; Ryzhov, V N; Tsiok, E N; Brazhkin, V V; Trachenko, K

    2014-01-01

    Recent advance in understanding the supercritical state posits the existence of a new line above the critical point separating two physically distinct states of matter: rigid liquid and non-rigid gas-like fluid. The location of this line, the Frenkel line, remains unknown for important real systems. Here, we map the Frenkel line on the phase diagram of supercritical iron using molecular dynamics simulations. On the basis of our data, we propose a general recipe to locate the Frenkel line for any system, the recipe that importantly does not involve system-specific detailed calculations and relies on the knowledge of the melting line only. We further discuss the relationship between the Frenkel line and the metal-insulator transition in supercritical liquid metals. Our results enable predicting the state of supercritical iron in several conditions of interest. In particular, we predict that liquid iron in the Jupiter core is in the "rigid liquid" state and is highly conducting. We finally analyse the evolution of iron conductivity in the core of smaller planets such as Earth and Venus as well as exoplanets: as planets cool off, the supercritical core undergoes the transition to the rigid-liquid conducting state at the Frenkel line. PMID:25424664

  2. Dynamic transition in supercritical iron

    PubMed Central

    Fomin, Yu. D.; Ryzhov, V. N.; Tsiok, E. N.; Brazhkin, V. V.; Trachenko, K.

    2014-01-01

    Recent advance in understanding the supercritical state posits the existence of a new line above the critical point separating two physically distinct states of matter: rigid liquid and non-rigid gas-like fluid. The location of this line, the Frenkel line, remains unknown for important real systems. Here, we map the Frenkel line on the phase diagram of supercritical iron using molecular dynamics simulations. On the basis of our data, we propose a general recipe to locate the Frenkel line for any system, the recipe that importantly does not involve system-specific detailed calculations and relies on the knowledge of the melting line only. We further discuss the relationship between the Frenkel line and the metal-insulator transition in supercritical liquid metals. Our results enable predicting the state of supercritical iron in several conditions of interest. In particular, we predict that liquid iron in the Jupiter core is in the “rigid liquid” state and is highly conducting. We finally analyse the evolution of iron conductivity in the core of smaller planets such as Earth and Venus as well as exoplanets: as planets cool off, the supercritical core undergoes the transition to the rigid-liquid conducting state at the Frenkel line. PMID:25424664

  3. Transit Fixatives: An Innovative Study

    PubMed Central

    A, Ravi Prakash; G, Sreenath; JK, Sonia Bai; NDVN, Shyam

    2015-01-01

    Background: Universally accepted fixative is 10% formalin which has been used for preserving the tissues and their architecture. In certain conditions, formalin might not be readily available for immediate fixation. We here by explore more economical, eco-friendly and easily available solutions that can be used as transit media/ transporting media for tissue specimens. Materials and Methods: The study included commonly available solutions like Spirit, Saline, Betadine solution, Hydrogen peroxide (H2O2), Local anesthesia (L.A), Rose water, Coconut oil, Coconut water, Ice cold water, Honey and Milk while keeping formalin as control. The fresh tissue sample was cut into multiple bits and placed in different containers for a period of 8 hours before transferring to formalin solution. Conclusion: Transit fixatives are very important in certain situations where formalin is not readily available. These fixatives can be used to fix the tissues for a period of at least 8 hours without causing any damage or distortion before they are fixed in formalin solution. PMID:25954725

  4. More holographic Berezinskii-Kosterlitz-Thouless transitions

    SciTech Connect

    Jensen, Kristan [Department of Physics, University of Washington, Seattle, Washington 98195-1560 (United States)

    2010-08-15

    We find two systems via holography that exhibit quantum Berezinskii-Kosterlitz-Thouless (BKT) phase transitions. The first is the ABJM theory with flavor and the second is a flavored (1, 1) little string theory. In each case the transition occurs at nonzero density and magnetic field. The BKT transition in the little string theory is the first example of a quantum BKT transition in (3+1) dimensions. As in the 'original' holographic BKT transition in the D3/D5 system, the exponential scaling is destroyed at any nonzero temperature and the transition becomes second order. Along the way we construct holographic renormalization for probe branes in the ABJM theory and propose a scheme for the little string theory. Finally, we obtain the embeddings and (half of) the meson spectrum in the ABJM theory with massive flavor.

  5. Wetting and layering transitions in liquid crystals

    NASA Astrophysics Data System (ADS)

    Somoza, A. M.; Mederos, L.; Sullivan, D. E.

    1995-11-01

    Interfacial structure in the isotropic phase of a liquid-crystalline material near a wall is studied by a mean-field density-functional theory. With increasing strength of the wall anchoring potential, the theory predicts a first-order transition from incomplete to complete wetting by the smectic-A phase at bulk isotropic-smectic coexistence, with an associated prewetting transition occurring away from bulk coexistence. The incomplete wetting case is accompanied by a small number (between 0 and and 2) of discrete layer transitions, while an infinite number of such transitions occurs at complete wetting. An analysis of the underlying physical mechanisns for layer transitions reveals that these transitions tend to disappear as the system is moved both sufficiently close to and sufficiently far from the bulk isotropic-nematic-smectic-A triple point by varying the model coupling parameters. These results reconcile findings from previous theories and experiments.

  6. An Observational Perspective of Transitional Disks

    E-print Network

    Espaillat, Catherine; Najita, Joan; Andrews, Sean; Zhu, Zhaohuan; Calvet, Nuria; Kraus, Stefan; Hashimoto, Jun; Kraus, Adam; D'Alessio, Paola

    2014-01-01

    Transitional disks are objects whose inner disk regions have undergone substantial clearing. The Spitzer Space Telescope produced detailed spectral energy distributions (SEDs) of transitional disks that allowed us to infer their radial dust disk structure in some detail, revealing the diversity of this class of disks. The growing sample of transitional disks also opened up the possibility of demographic studies, which provided unique insights. There now exist (sub)millimeter and infrared images that confirm the presence of large clearings of dust in transitional disks. In addition, protoplanet candidates have been detected within some of these clearings. Transitional disks are thought to be a strong link to planet formation around young stars and are a key area to study if further progress is to be made on understanding the initial stages of planet formation. Here we provide a review and synthesis of transitional disk observations to date with the aim of providing timely direction to the field, which is about...

  7. Testing of transition-region models

    NASA Technical Reports Server (NTRS)

    Singer, B. A.; Dinavahi, P. G.

    1992-01-01

    An approach for the comprehensive testing of transition-region models is described. This approach emphasizes the need to evaluate the models in all of the flow scenarios for which they are likely to be used. As an example of the procedure, seven different types of transitioning flows are described and experiments illustrating the different scenarios are discussed. Two transition-region models are used to predict mean-flow quantities for all of the cases and selected results are reported.

  8. Transition rates of electrons in superheavy elements

    Microsoft Academic Search

    Gerhard Soff; Berndt Müller

    1977-01-01

    Transition rates for electrons in the superheavy elementsZ=114, 126, 134, 145, 164 and 173 are calculated.K, L andM-shells are considered as final states. The 2s-1s transition of multipolarityM 1 is dominant for Z = 173 with a transition time of 10-18 s. The radical expectation values and 2>1\\/2 are given.

  9. New O(3) transition in three dimensions

    NASA Astrophysics Data System (ADS)

    Kamal, Michael; Murthy, Ganpathy

    1993-09-01

    A three-dimensional lattice of Heisenberg spins with nearest-neighbor interactions is studied by numerical simulation under the constraint that no free topological singularities (hedgehogs) are allowed. Only nearest-neighbor pairs of oppositely charged hedgehogs are permitted in the sum over configurations. A disordering transition with exponents different from the usual Heisenberg transition is found and tentatively identified as a pure spin wave disordering transition.

  10. Improved parameters for extrasolar transiting planets

    Microsoft Academic Search

    Guillermo Torres; Joshua N. Winn; Matthew J. Holman

    2008-01-01

    We present refined values for the physical parameters of transiting\\u000aexoplanets, based on a self-consistent and uniform analysis of transit light\\u000acurves and the observable properties of the host stars. Previously it has been\\u000adifficult to interpret the ensemble properties of transiting exoplanets,\\u000abecause of the widely different methodologies that have been applied in\\u000aindividual cases. Furthermore, previous studies often

  11. Mass Transit Living Lab: Improve the System

    NSDL National Science Digital Library

    Civil and Environmental Engineering Department,

    Students go through the process of identifying possible solutions to the design problems that the existing west corridor transit system faces. Students combine what they have learned from the three previous activities to come up with possible solutions to the design problems faced by the system. This activity requires the use of the Mass Transit Living Lab—a web portal to interactive train (transit) traffic data for a major metropolitan city.

  12. Continuous and discontinuous metal-insulator transitions

    Microsoft Academic Search

    N. F. Mott

    1978-01-01

    In non-crystalline systems a continuous metal-insulator transition of Andersontype is frequently observed when the Fermi energy moves through a mobility edge. In crystalline systems, on the other hand, the activation energy for conduction should change discontinuously at the transition. The aim of this paper is to enquire under what conditions a discontinuous transition can occur in non-crystalline systems. It clearly

  13. The Demographic Transition: Causes and Consequences

    PubMed Central

    Galor, Oded

    2013-01-01

    This paper develops the theoretical foundations and the testable implications of the various mechanisms that have been proposed as possible triggers for the demographic transition. Moreover, it examines the empirical validity of each of the theories and their significance for the understanding of the transition from stagnation to growth. The analysis suggests that the rise in the demand for human capital in the process of development was the main trigger for the decline in fertility and the transition to modern growth PMID:25089157

  14. Vibronic transitions in rare earth spectroscopy

    Microsoft Academic Search

    G. Blasse

    1992-01-01

    An overview of the studies of vibronic transitions in the rare earth ions is given with special attention to the intraconfigurational transitions. First the general theory is shortly reviewed, later that of the rare-earth vibronic transitions. The vibronic spectroscopy of Gd3+ is extensively dealt with, because it is an ideal ion for this type of study due to its non-degenerate

  15. A critical look at transition ratings

    Microsoft Academic Search

    Gordon H. Guyatt; Geoffrey R. Norman; Elizabeth F. Juniper; Lauren E. Griffith

    2002-01-01

    Patient ratings of the extent to which they have improved or deteriorated—transition ratings—are extremely common in clinical practice and clinical research. However, some have raised concerns about transition rating validity. We examined data from three studies, each of which explored the relation between a disease-specific health-related quality of life (HRQL) instrument and transition ratings corresponding to instrument domains. For instance,

  16. X-Ray Transition Energies Database

    National Institute of Standards and Technology Data Gateway

    SRD 128 X-Ray Transition Energies Database (Web, free access)   This X-ray transition table provides the energies and wavelengths for the K and L transitions connecting energy levels having principal quantum numbers n = 1, 2, 3, and 4. The elements covered include Z = 10, neon to Z = 100, fermium. There are two unique features of this data base: (1) a serious attempt to have all experimental values on a scale consistent with the International System of measurement (the SI) and (2) inclusion of accurate theoretical estimates for all transitions.

  17. The Helix Coil Transition of DNA

    ERIC Educational Resources Information Center

    Steinert, Roger; Hudson, Bruce

    1973-01-01

    This transition, observed with an inexpensive ultraviolet photometer, is a potentially useful experiment for an advanced freshman class because it introduces several concepts of general physical interest. (DF)

  18. Topological transition in aqueous nonionic micellar solutions.

    PubMed

    Kwon, Su Yong; Kim, Mahn Won

    2002-12-16

    We have studied the topological transition of the nonionic micelles of a penta-ethyleneglycol mono n-dodecyl ether (C12E5)/DL-alpha-phosphatidylcholine Dimyristoyl (DMPC) mixture in water by light scattering and viscosity measurements. The topological transition concentration decreases with an increase of the mixing ratio of DMPC to C12E5. The topological transition point is strongly affected by defect energies of the end cap (epsilon(1)) and a threefold junction (epsilon(3)) and is compared with a recent theoretical study. This experimental study shows the first clear evidence for the topological transition in a nonionic micellar system resulting from balancing the defect energies. PMID:12484925

  19. Detecting New Planets in Transiting Systems

    E-print Network

    Jason H. Steffen

    2006-09-18

    I present an initial investigation into a new planet detection technique that uses the transit timing of a known, transiting planet. The transits of a solitary planet orbiting a star occur at equally spaced intervals in time. If a second planet is present, dynamical interactions within the system will cause the time interval between transits to vary. These transit time variations can be used to infer the orbital elements of the unseen, perturbing planet. I show analytic expressions for the amplitude of the transit time variations in several limiting cases. Under certain conditions the transit time variations can be comparable to the period of the transiting planet. I also present the application of this planet detection technique to existing transit observations of the TrES-1 and HD209458 systems. While no convincing evidence for a second planet in either system was found from those data, I constrain the mass that a perturbing planet could have as a function of the semi-major axis ratio of the two planets and the eccentricity of the perturbing planet. Near low-order, mean-motion resonances (within about 1% fractional deviation), I find that a secondary planet must generally have a mass comparable to or less than the mass of the Earth--showing that these data are the first to have sensitivity to sub Earth-mass planets orbiting main sequence stars. These results show that TTV will be an important tool in the detection and characterization of extrasolar planetary systems.

  20. Transitions between patterns in thermal convection

    SciTech Connect

    Bodenschatz, E.; de Bruyn, J.R.; Ahlers, G.; Cannell, D.S. (Department of Physics and Center for Nonlinear Science, University of California, Santa Barbara, Santa Barbara, California (USA) Memorial University of Newfoundland, St. John's, Newfoundland (Canada))

    1991-11-25

    We present experimental studies of the transitions between conduction, hexagons, and rolls in non-Boussinesq convection of gaseous CO{sub 2} in a cylindrical cell of radius-to-height ratio 86. Except for the transition from conduction to hexagons, transitions occur when the two states involved have nearly the same value of a generalized potential rather than at the stability limits. Conduction gives way to hexagons via the propagation of a front connecting the two states, while the transitions between hexagons and rolls are facilitated at the cell walls which appear to nucleate the minority state.

  1. Observations of Extrasolar Planet Transits: What's next?

    NASA Astrophysics Data System (ADS)

    Rauer, H.

    2014-03-01

    Transits of extrasolar planets are a goldmine for our understanding of the physical nature of planets beyond the Solar System. Measurements of radii from transit observations combined with mass determinations from radial velocity spectroscopy, or transit timing variations, have provided the first indications to the planetary composition and interior structure. It turns out that planets show a much richer diversity than found in our own planetary system, considering e.g. the so-called 'super-Earths', 'mini-Neptunes', and inflated giant planets. Transiting exoplanets also allow for spectroscopic observations of their atmospheres, either during transit or near secondary eclipse. Exoplanets showing transits have therefore been identified as key observables, not only for planet detection, but in particular for investigating further planetary nature. As a result, a new generation of instruments (space- and groundbased) for exoplanet transit observations is already in the construction phase and is planned for the near future. Most of these target specifically stars bright enough for spectroscopic follow-up observations, a èlesson learned' from past transit surveys. A clear goal for future investigations of habitable planets is the detection and characterization of terrestrial planets which potentially could harbor life. This talk will review the status and in particular the future of transit observations, with a focus on rocky planets in the habitable zone of their host stars.

  2. SUCCESSFUL TRANSITION Counseling & Substance Abuse Services

    E-print Network

    Kasman, Alex

    SUCCESSFUL TRANSITION TO COLLEGE Counseling & Substance Abuse Services Director, Frank Budd, Ph · Their Residence Assistant or the RHD · Center for Student Learning · Counseling and Substance Abuse Services

  3. SUCCESSFUL TRANSITION Counseling & Substance Abuse Services

    E-print Network

    Kunkle, Tom

    SUCCESSFUL TRANSITION TO COLLEGE Counseling & Substance Abuse Services Director, Frank Budd, Ph and Substance Abuse Services · Undergraduate Academic Services · Dean of Students · Their Professor during

  4. Negative refraction using Raman transitions and chirality

    NASA Astrophysics Data System (ADS)

    Sikes, D. E.; Yavuz, D. D.

    2011-11-01

    We present a scheme that achieves negative refraction with low absorption in far-off resonant atomic systems. The scheme utilizes Raman resonances and does not require the simultaneous presence of an electric-dipole transition and a magnetic-dipole transition near the same wavelength. We show that two interfering Raman tran-sitions coupled to a magnetic-dipole transition can achieve a negative index of refraction with low absorption through magnetoelectric cross-coupling. We confirm the validity of the analytical results with exact numerical simulations of the density matrix. We also discuss possible experimental implementations of the scheme in rare-earth metal atomic systems.

  5. Insight into the denaturation transition of DNA.

    PubMed

    Hammouda, Boualem

    2009-12-01

    DNA undergoes a helix-to-coil transition (also called denaturation transition) upon heating. This transition can also be facilitated by using solvent mixtures (for example water-alcohol). An increase in the hydrophobic tail of the second solvent molecule first decreases then increases the melting temperature appreciably. Measurement on 4% DNA in a series of water-alcohol mixtures shows that the helix-to-coil melting transition is driven by the solvent ability to cross the hydrophobic sugar-rich region. DNA is behaving like a cylindrical micelle. PMID:19769999

  6. Kepler Stars with Multiple Transiting Planet Candidates

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.

    2012-01-01

    NASA's Kepler spacecraft was launched into an Earth-trailing heliocentric orbit in March of 2009. Kepler is designed to conduct a statistical census of planetary system properties using transit photometry. Among the most exciting early results from Kepler are target stars found to have photometric signatures that suggest the presence of more than one transiting planet. Individual transiting planets provide information on the size and orbital period distributions of exoplanets. Multiple transiting planets provide additional information on the spacing and flatness distributions of planetary systems. Results to d ate and plans for future analysis will be presented.

  7. Lifshitz transition in Kondo alloys.

    PubMed

    Burdin, Sébastien; Lacroix, Claudine

    2013-05-31

    We study the low-energy states of Kondo alloys as a function of the magnetic impurity concentration per site x and the conduction electron average site occupation n(c). Using two complementary approaches, the mean-field coherent potential approximation and the strong-coupling limit, we identify and characterize two different Fermi-liquid regimes. We propose that both regimes are separated by a Lifshitz transition at x=n(c). Indeed, we predict a discontinuity of the number of quasiparticles that are enclosed in the Fermi surface. This feature could provide a scenario for the non-Fermi liquid properties that were recently observed in Kondo alloy systems around x=n(c). PMID:23767739

  8. Transition to turbulence in ferrofluids

    E-print Network

    Altmeyer, Sebastian; Lai, Ying-Cheng

    2015-01-01

    It is known that in classical fluids turbulence typically occurs at high Reynolds numbers. But can turbulence occur at low Reynolds numbers? Here we investigate the transition to turbulence in the classic Taylor-Couette system in which the rotating fluids are manufactured ferrofluids with magnetized nanoparticles embedded in liquid carriers. We find that, in the presence of a magnetic field turbulence can occur at Reynolds numbers that are at least one order of magnitude smaller than those in conventional fluids. This is established by extensive computational ferrohydrodynamics through a detailed bifurcation analysis and characterization of behaviors of physical quantities such as the energy, the wave number, and the angular momentum through the bifurcations. A striking finding is that, as the magnetic field is increased, the onset of turbulence can be determined accurately and reliably. Our results imply that experimental investigation of turbulence can be greatly facilitated by using ferrofluids, opening up...

  9. Synthesis of transition metal carbonitrides

    DOEpatents

    Munir, Zuhair A. R. (Davis, CA); Eslamloo-Grami, Maryam (Davis, CA)

    1994-01-01

    Transition metal carbonitrides (in particular, titanium carbonitride, TiC.sub.0.5 N.sub.0.5) are synthesized by a self-propagating reaction between the metal (e.g., titanium) and carbon in a nitrogen atmosphere. Complete conversion to the carbonitride phase is achieved with the addition of TiN as diluent and with a nitrogen pressure .gtoreq.0.6 MPa. Thermodynamic phase-stability calculations and experimental characterizations of quenched samples provided revealed that the mechanism of formation of the carbonitride is a two-step process. The first step involves the formation of the nonstoichiometric carbide, TiC.sub.0.5, and is followed by the formation of the product by the incorporation of nitrogen in the defect-structure carbide.

  10. Chicago Transit Authority: Public Art

    NSDL National Science Digital Library

    The Chicago Transit Authority (CTA) has long had an ambitious public art program. This handy 62-page guidebook provides interested parties and tourists with a complete listing of these works. Not surprisingly, the works are arranged by elevated line and by stop. The guide starts with providing information about works on the Brown Line, which is a great place to begin. It's a real treat to start with Josh Garber's "Hope and Renewal" which is located at the Kimball stop at the end of the Brown Line in the Albany Park community. Also, baseball fans won't want to miss the artworks located close to the train stations at Wrigley Field and US Cellular Field. The guide also includes an artist index and information about the gorgeous works at CTA headquarters in the city's Near West Side neighborhood.

  11. Transition Radiation Detector in MACRO

    E-print Network

    M. N. Mazziotta; for the MACRO Collaboration

    1999-05-13

    The MACRO detector is located in the Gran Sasso Laboratory. MACRO's overburden varies from 3150 to 7000 hg/cm^2. A transition radiation detector (TRD) has been added to the MACRO detector in order to measure the residual energy of muons entering MACRO, i.e. the energy they have after passing through the Gran Sasso's rock overburden. The TRD consists of three identical modules with a total horizontal area of 36 m^2. The results presented here are referred to single and double events in MACRO with one muon crossing one of the TRD modules. Our data show that double muons are more energetic than single ones, as predicted by the interaction models of primary cosmic rays with the atmosphere.

  12. Brain Performance versus Phase Transitions

    PubMed Central

    Torres, Joaquín J.; Marro, J.

    2015-01-01

    We here illustrate how a well-founded study of the brain may originate in assuming analogies with phase-transition phenomena. Analyzing to what extent a weak signal endures in noisy environments, we identify the underlying mechanisms, and it results a description of how the excitability associated to (non-equilibrium) phase changes and criticality optimizes the processing of the signal. Our setting is a network of integrate-and-fire nodes in which connections are heterogeneous with rapid time-varying intensities mimicking fatigue and potentiation. Emergence then becomes quite robust against wiring topology modification—in fact, we considered from a fully connected network to the Homo sapiens connectome—showing the essential role of synaptic flickering on computations. We also suggest how to experimentally disclose significant changes during actual brain operation. PMID:26193453

  13. Dynamical transitions of turing patterns.

    SciTech Connect

    Kaper, H. G.; Wang, S.; Yari, M.; Mathematics and Computer Science; Indiana Univ.

    2009-01-01

    This paper is concerned with the formation and persistence of spatiotemporal patterns in binary mixtures of chemically reacting species, where one of the species is an activator, the other an inhibitor of the chemical reaction. The system of reaction-diffusion equations is reduced to a finite system of ordinary differential equations by a variant of the centre-manifold reduction method. The reduced system fully describes the local dynamics of the original system near transition points at the onset of instability. The attractor-bifurcation theory is used to give a complete characterization of the bifurcated objects in terms of the physical parameters of the problem. The results are illustrated for the Schnakenberg model.

  14. THE TRANSIT LIGHT CURVE PROJECT. X. A CHRISTMAS TRANSIT OF HD 17156b

    E-print Network

    Winn, Joshua Nathan

    Photometry is presented of the 2007 December 25 transit of HD 17156b, which has the longest orbital period and highest orbital eccentricity of all the known transiting exoplanets. New measurements of the stellar radial ...

  15. Picocyanobacteria in Adriatic transitional environments

    NASA Astrophysics Data System (ADS)

    Paoli, Alessandro; Celussi, Mauro; Valeri, Annalisa; Larato, Chiara; Bussani, Andrea; Umani, Serena Fonda; Vadrucci, Maria Rosaria; Mazziotti, Cristina; Del Negro, Paola

    2007-10-01

    In the marine realm picoplanktonic cyanobacteria (PC) show a broad distribution from the surface ocean to the offshore and coastal waters of semi-enclosed seas and, because of their photoheterotrophy, they are responsible for a substantial fraction of both primary production and organic matter degradation/utilization. In the present study, we investigated PC distribution related to some physical-chemical parameters (temperature, salinity and dissolved oxygen), in the most productive periods of the year, spring and fall, at 37 stations located in seven transitional systems all along the Italian coast of the Adriatic Sea: Grado and Marano, Venezia, Pialassa Baiona, Margherita di Savoia, Torre Guaceto, Cesine and Alimini. The aim of the study was to determine if PC are common elements of these transitional systems (lagoons, marshes and solar salterns) or whether they are only occasionally important during stochastic bloom events. PC mean abundances were all over the seven habitats more than one order of magnitude higher (>5 × 10 7 cells L -1) than those found in coastal and offshore waters of the Adriatic Sea. Their range of variability was also broader (10 5-10 9 cells L -1 vs. 10 6-10 8 cells L -1). PC populations appeared well adapted to ample variations in salinity (5-87). The highest abundances (close to 10 9 cells L -1) were found at extremely high/low salinity values. Even oxygen concentrations close to hypoxia did not seem to negatively affect PC abundances. Because of their ability in adapting to extreme conditions, PC may become the prevailing fraction of the phototrophic plankton in these sites and their role in such ecosystems should not be underestimated.

  16. New optimization method for urban transit network-CVO method

    Microsoft Academic Search

    Yonggang Zhu; Shuzhi Zhao; Lianfu Zhang

    2008-01-01

    Transit network planning project is implemented by a series of short-term transit network optimization processes. Considering transit flows data is easily got by transit companies, this paper introduces a simple new method on short-term optimization for transit network - CVO method, which is convenient for transit companies. The CVO method is realized with the transportation software -TransCAD based on transit

  17. Cosmological Consequences of QCD Phase Transition(s) in Early Universe

    SciTech Connect

    Tawfik, A. [ECTP, Egyptian Center for Theoretical Physics, MTI Modern University, Mukattam Cairo (Egypt)

    2009-04-17

    We discuss the cosmological consequences of QCD phase transition(s) on the early universe. We argue that our recent knowledge about the transport properties of quark-gluon plasma (QGP) should thraw additional lights on the actual time evolution of our universe. Understanding the nature of QCD phase transition(s), which can be studied in lattice gauge theory and verified in heavy ion experiments, provides an explanation for cosmological phenomenon stem from early universe.

  18. Determining Transit’s Impact on Seoul Commercial Land Values: An Application of Spatial Econometrics

    Microsoft Academic Search

    Jin Kim; Ming Zhang

    2005-01-01

    Literature regarding transit’s impact on land values reports mixed results concerning the economic benefits of accessibility to subway stations, specifically regarding commercial properties. After examining 731 commercial land values in Seoul, Korea, this study suggests a possible explanation for the mixed results: transit’s discrimination impact on land values by location in a built-up urban area. The regression coefficient for distance

  19. Electric quadrupole transitions in x-ray spectra: 3d transition-metal oxides

    Microsoft Academic Search

    N. V. Dobrodey; Yu. V. Luniakov

    1995-01-01

    The intensities of the electric quadrupole transitions in the x-ray spectra of the 3d-transition-metal monoxide diatomic molecules were calculated using the discrete variational method of the local-density approximation. The quadrupole transition intensities have been found to be negligible for the left-hand-side 3d metal oxides. It was shown that the electric quadrupole transitions can appreciably contribute to the MKbeta5 emission spectra

  20. Making the Transition to Primary School: An Evaluation of a Transition Program for Parents

    ERIC Educational Resources Information Center

    Giallo, Rebecca; Treyvaud, Karli; Matthews, Jan; Kienhuis, Mandy

    2010-01-01

    The transition to primary school is an important time for both children and parents. The aim of this randomized controlled study was to assess the effectiveness of a Transition to Primary School Parent Program in strengthening parent knowledge and confidence to manage the transition process, increasing parent involvement in their children's…

  1. Making the Transition to Primary School: An Evaluation of a Transition Program for Parents

    Microsoft Academic Search

    Rebecca Giallo; Karli Treyvaud; Jan Matthews

    2010-01-01

    The transition to primary school is an important time for both children and parents. The aim of this randomized controlled study was to assess the effectiveness of a Transition to Primary School Parent Program in strengthening parent knowledge and confidence to manage the transition process, increasing parent involvement in their children's learning, and improving child adjustment to starting school. Participants

  2. Europe in Transition -2013 SYLLABUS--International Study, SAEUR 301, Europe in Transition

    E-print Network

    Gering, Jon C.

    Europe in Transition - 2013 SYLLABUS--International Study, SAEUR 301, Europe in Transition hours of the program Europe in Transition is an international study program combining study and field will be observed. The group will learn how to travel in Europe. An appreciation and acceptance of cultural

  3. Glass transition studies in free standing polymer films have revealed values of the transition temperature, Tg

    E-print Network

    Dutcher, John

    78 Glass transition studies in free standing polymer films have revealed values of the transition which examine the dynamics and glass transition temperature, Tg , of thin polymer films supported by sub temperature, Tg , which were substantially reduced below the bulk for suf- ficiently thin films. Measurements

  4. THE EFFECT OF THE TRANSIT OF VENUS ON ACRIM'S TOTAL SOLAR IRRADIANCE MEASUREMENTS: IMPLICATIONS FOR TRANSIT

    E-print Network

    Schneider, Glenn

    intrinsically limit such transit obser- vations. During the Venus transit, which lasted $5.5 hr, the planet headinggs: planets and satellites: individual (Venus) -- techniques: photometric 1. INTRODUCTION SinceTHE EFFECT OF THE TRANSIT OF VENUS ON ACRIM'S TOTAL SOLAR IRRADIANCE MEASUREMENTS: IMPLICATIONS

  5. Transition Management: The Student Teacher's Achilles Heel.

    ERIC Educational Resources Information Center

    Martin, Dawn Vincent

    Classroom observation of four student teachers during the first, seventh, and fourteenth weeks of their teaching semester focused on their management of transition periods between lesson segments. Videotapes and stimulated recall analysis of the differences revealed that: (1) the most effective student teachers averaged fewer transitions per…

  6. Random effects model for credit rating transitions

    Microsoft Academic Search

    Yoonseong Kim; So Young Sohn

    2008-01-01

    This paper proposes a random effects multinomial regression model to estimate transition probabilities of credit ratings. Unlike the previous studies on the rating transition, we applied a random effects model, which accommodates not only the environmental characteristics of the exposures of a rating but also the uncertainty not explained by such factors. The rating category specific factors such as retained

  7. Transiting Exoplanet Observations at Grinnell College

    NASA Astrophysics Data System (ADS)

    Sauerhaft, Julia; Slough, P.; Cale, B.; Kempton, E.

    2014-01-01

    Grinnell College, a small liberal arts college in Grinnell, Iowa with 1600 undergraduate students, is home to the Grant O. Gale Observatory. Over the past year, we have successfully detected extrasolar planets using the transit method with our 24-inch Cassegrain reflecting telescope equipped with a CCD camera. With little light pollution and an easily accessible observatory, Grinnell College is an optimal location for transiting exoplanet observations. With the current telescope set-up and CCD camera, we have taken time series data and created image calibration and post-processing programs that detect exoplanet transits at high photometric precision. In the future, we will continue to use these observation and data reduction procedures to conduct transiting exoplanet research. Goals for our research program include performing follow-up observations of transiting exoplanet candidates to confirm their planetary nature, searching for additional exoplanets in known planetary systems using the transit timing detection method, tracking long period transiting planets, and refining properties of exoplanets and their host stars. Ground-based transiting planet science is especially important in the post-Kepler era, and our dedicated mid-sized telescope with plenty of access to dark clear nights provides an ideal resource for a variety of follow up and exoplanet detection efforts.

  8. BUS DISPATCHING AT TIMED TRANSFER TRANSIT STATIONS

    E-print Network

    Dessouky, Maged

    BUS DISPATCHING AT TIMED TRANSFER TRANSIT STATIONS USING BUS TRACKING TECHNOLOGY May 26, 1999 Maged of Southern California Los Angeles, CA 90089-0193 #12;BUS DISPATCHING AT TIMED TRANSFER TRANSIT STATIONS USING Of Delay For Given Lateness Intervals For Bus Line #26 3. Summary Of Results For The Different Dispatching

  9. An Exploratory Study of Transition, Inc.

    ERIC Educational Resources Information Center

    Hogges, Ralph; Hogges, Lilia

    In this paper the Transition, Inc. program of the city of Miami is examined. This program's main concern is to help ex-offenders in their re-socialization process by offering them moral as well as financial support. It is evidenced from the goal and objectives of the Transition, Inc. program, its rehabilitative results and related literature that…

  10. Winners and Losers in Russia's Economic Transition

    Microsoft Academic Search

    Elizabeth Brainerd

    1998-01-01

    The transition to a market economy has produced a substantial and rapid change in the wage structure in Russia. Household surveys taken before and after the transition indicate that overall wage inequality nearly doubled from 1991 to 1994 and has reached a level higher than that in the United States. Returns to both measured skills (education, occupation) and unmeasured skills

  11. Russia between transition and globalization Olga GARANINA

    E-print Network

    Paris-Sud XI, Université de

    Russia between transition and globalization Olga GARANINA PhD student University Pierre Mendes France of Grenoble (France) St Petersburg State University of Economics and Finance (Russia) Mailing the beginning of the transition. We study the politico-economic configuration in Russia in terms of (i) its

  12. Phase transitions in alkylammonium halogenoantimonates and bismuthates

    Microsoft Academic Search

    Ryszard Jakubas; Lucjan Sobczyk

    1990-01-01

    A review of the results of studies on the structure, phase transitions and physical properties of alkylammonium halogenoantimonates (III) and bismuthates (III) is presented. The crystals of these compounds are characterized by a variety of anionic structures and show a number of phase transitions including those to polar phases. We concentrate here mainly on dielectric and pyroelectric properties, spontaneous polarization

  13. Deconfining phase transition in lattice quantum chromodynamics

    SciTech Connect

    Gottlieb, S.A.; Kuti, J.; Toussaint, D.; Kennedy, A.D.; Meyer, S.; Pendleton, B.J.; Sugar, R.L.

    1986-06-01

    We present a large-scale Monte Carlo calculation of the deconfining phase transition temperature in lattice quantum chromodynamics without fermions. Using the Wilson action, the transition temperature as a function of the lattice coupling g-italic is consistent with scaling behavior dictated by the perturbative ..beta.. function for 6/g-italic/sup 2/>6.15.

  14. Conformational Transitions in Model Silk Peptides

    Microsoft Academic Search

    Donna Wilson; Regina Valluzzi; David Kaplan

    2000-01-01

    Protein structural transitions and ?-sheet formation are a common problem both in vivo and in vitro and are of critical relevance in disparate areas such as protein processing and ?-amyloid and prion behavior. Silks provide a “databank” of well-characterized polymorphic sequences, acting as a window onto structural transitions. Peptides with conformationally polymorphic silk-like sequences, expected to exhibit an intractable ?-sheet

  15. Transition: Old Wine in New Bottles.

    ERIC Educational Resources Information Center

    Halpern, Andrew S.

    1992-01-01

    The 1980s movement for improved transition of handicapped youth from school to work is considered in light of similar previous movements: (1) the career education movement of the 1970s and (2) the work/study movement of the 1960s. The influence of broad social issues (such as educational reform) on outcomes for the transition movement is stressed.…

  16. Transit - The first navigational satellite system

    Microsoft Academic Search

    G. Richards

    1979-01-01

    The Transit navigational satellite system, providing fixes of high accuracy for ships, is discussed. The Transit satellite, with an orbit of about 1100 km, uses a radio-Doppler navigation method in which the ship's position is calculated from the observed change in the received frequency of the satellite's radio transmissions. The satellite carries an ultra-stable oscillator to control the transmitter frequency,

  17. Stellar transits in active galactic nuclei

    E-print Network

    Béky, Bence

    2012-01-01

    Supermassive black holes (SMBH) are typically surrounded by a dense stellar population in galactic nuclei. Stars crossing the line of site in active galactic nuclei (AGN) produce a characteristic transit lightcurve, just like extrasolar planets do when they transit their host star. We examine the possibility of finding such AGN transits in deep optical, UV, and X-ray surveys. We calculate transit lightcurves using the Novikov--Thorne thin accretion disk model, including general relatistic effects. Based on the expected properties of stellar cusps, we find that around 10^6 solar mass SMBHs, transits of red giants are most common for stars on close orbits with transit durations of a few weeks and orbital periods of a few years. We find that detecting AGN transits requires repeated observations of thousands of low mass AGNs to 1% photometric accuracy in optical, or ~ 10% in UV bands or soft X-ray. It may be possible to identify stellar transits in the Pan-STARRS and LSST optical and the eROSITA X-ray surveys. Su...

  18. Economic vulnerability and the energy transition

    Microsoft Academic Search

    1983-01-01

    The United States is currently undergoing a transition from rapidly depleting nonrenewable energy sources to ''backstop'' energy sources. A system dynamics model has been developed to analyze the macroeconomic effects of the energy transition. GNP, consumption, investment, wages and prices, and other major energy and economic aggregates are determined endogenously. The model shows how delays in substitution and the development

  19. Building bridges: understanding student transition to university

    Microsoft Academic Search

    A. R. J. Briggs; J. Clark; I. Hall

    2012-01-01

    This article explores challenges in ensuring effective student transition from school or college to university. It examines the complex liaison needed for students to progress to appropriate courses, settle into university life and succeed as higher education learners. Secondary data (international literature on transition and the formation of learner identity) are analysed to identify underpinning concepts. Primary data are taken

  20. Factors Affecting Third Culture Kids' (TCKs) Transition

    ERIC Educational Resources Information Center

    Morales, Antonio

    2015-01-01

    (TCKs) transition becomes challenging for both the student and the school. The programs implemented, or lack thereof, are imperative to the successful transition of TCKs into their new, diverse, multicultural environment. Research has been written on the positive effects and challenges faced by TCKs' transient lifestyle. Although international…

  1. TRACE (Transition Region and Coronal Explorer)

    NASA Astrophysics Data System (ADS)

    Handy, B.; Murdin, P.

    2000-11-01

    The Transition Region and Coronal Explorer (TRACE) is a NASA Small-Explorer (SMEX) satellite developed to study the impact of magnetic fields on the solar outer atmosphere. The instrument observes the solar surface (SOLAR PHOTOSPHERE) and the hotter overlying domains (TRANSITION REGION and CORONA) with an angular resolution of 1 arcsec, equivalent to 725 km on the Sun, an average cadence of about...

  2. Transitive Mesh Space of a Progressive Mesh

    Microsoft Academic Search

    Junho Kim; Seungyong Lee

    2003-01-01

    This paper investigates the set of all selectively refined meshes that can be obtained from a progressive mesh. We call the set the transitive mesh space of a progressive mesh and present a theoretical analysis of the space. We define selective edge collapse and vertex split transformations, which we use to traverse all selectively refined meshes in the transitive mesh

  3. Energy Transition Initiative: Islands Playbook (Book)

    SciTech Connect

    Not Available

    2015-01-01

    The Island Energy Playbook (the Playbook) provides an action-oriented guide to successfully initiating, planning, and completing a transition to an energy system that primarily relies on local resources to eliminate a dependence on one or two imported fuels. It is intended to serve as a readily available framework that any community can adapt to organize its own energy transition effort.

  4. Transitions to College: From Theory to Practice

    ERIC Educational Resources Information Center

    Social Science Research Council, 2004

    2004-01-01

    In the fall of 2003 the Social Science Research Council (SSRC) established a project entitled "Transitions to College: From Theory to Practice." This project focuses on postsecondary transition and retention successes and failures associated with America's disadvantaged youth. Lumina Foundation for Education is providing support for this effort.…

  5. Thermal comfort in urban transitional spaces

    Microsoft Academic Search

    Chungyoon Chun; Akihiro Tamura

    2005-01-01

    This paper deals with thermal comfort in urban transitional spaces. This topic investigates thermal comfort during walking activities through transitional spaces-urban corridors, shopping streets, and open-ended passageways. The study involves a field study and a laboratory study with a sequenced walk through an environmental control chamber. Subjects in both studies wore the same clothing ensembles, walked the same speed, and

  6. Venus' Transit of 1874 Observed in Romania

    NASA Astrophysics Data System (ADS)

    Stavinschi, Magda

    Venus' transit across the solar disk in 1874 was observed in Romania, too. We present the Romanian (Neculai Culianu and ?efan Micle) and Austrian (Theodor von Oppolzer and Edmund Weiss) personalities who observed the transit, as well as the event as seen from Jassy.

  7. The Role of Transitions in ESL Instruction

    ERIC Educational Resources Information Center

    Steinman, Linda

    2013-01-01

    Transitions in ESL contexts generally refer to those linking words placed between sentences and between paragraphs. Transitions in writing (and in speaking) are helpful; they facilitate coherence and cohesion when used correctly. Understanding them when reading allows us to join the writer in seeing why and how idea B follows idea A. In this…

  8. Cell Stem Cell Sic Transit Gloria

    E-print Network

    Simons, Ben

    Cell Stem Cell Review Sic Transit Gloria: Farewell to the Epidermal Transit Amplifying Cell? Philip, Cambridge CB2 0RE, UK 4Wellcome Trust Centre for Stem Cell Research, Tennis Court Road, Cambridge CB2 1QR, UK *Correspondence: phj20@hutchison-mrc.cam.ac.uk DOI 10.1016/j.stem.2007.09.014 For the past 30

  9. Transition Metal Sulfide Electrocatalysts for PEM Fuel

    E-print Network

    Transition Metal Sulfide Electrocatalysts for PEM Fuel Cells Hua Zhang1, Ysmael Verde-Gómez1 Paso, TX 79968 Transition Metal Sulfide Electrocatalysts for PEM Fuel Cells Hua Zhang1, Ysmael-ray diffraction patterns of RuSx RuSx dispersion on carbon (TEM image) and RuSx/C sample: RuSx/C-1A #12

  10. Transit Fare Arrangements for Public Employees

    Microsoft Academic Search

    Daniel K Boyle

    2010-01-01

    The purpose of this synthesis is to document the state of the practice for transit agencies in terms of fare arrangements for public employees. Results of a cross-section survey of transit agencies in North America yielded information on important issues such as leadership of the program; barriers, obstacles, and constraints; administrative procedures; implementation; lessons learned; cost, financing, and pricing; and

  11. Formal Transition in Agent Organizations Eric Matson

    E-print Network

    Deloach, Scott A.

    becomes an even more useful structure capable of taking on problems that require self define organization transition. Specifically, we describe a formal process of organi- zation transition to be employed. Because of high turnover, the company will not be capable of remaining competitive

  12. Glass Transition Measurements of Ultrathin Polystyrene Films

    E-print Network

    1 Glass Transition Measurements of Ultrathin Polystyrene Films Cynthia Buenviaje, Franco Dinelli. Measurements taken on polystyrene surfaces of various film thickness provide insight into how the glass of polymers have been studied extensively, many properties of thin films, specifically the glass transition

  13. Boundary layer transition in hypersonic flows

    NASA Technical Reports Server (NTRS)

    Malik, M. R.; Zang, T. A.; Bushnell, D. M.

    1990-01-01

    This paper summarizes some of the recent progress made at NASA Langley Research Center in the understanding, prediction and modeling of high speed boundary-layer transition. Linear and nonlinear theories together with large-eddy and direct numerical simulations have been used to understand various aspects of the transition problem while low disturbance 'quiet' tunnels provide means for validating the theoretical results.

  14. School Change through Transition Education Initiatives.

    ERIC Educational Resources Information Center

    Kennedy, Kerry J.; Fraser, Barry J.

    This paper reviews transition education initiatives that were undertaken in three Australian states (Western Australia, South Australia, and Victoria) for the purpose of assessing the extent to which local projects reflected national policy objectives. Case studies for each of the three states are presented and the impacts of the transition

  15. Review of Transition from Home to School.

    ERIC Educational Resources Information Center

    Richardson, Lesley

    1997-01-01

    Examines transition of children from home or preschool to school in Australia and New Zealand. Almost all Australian states have a "reception" or kindergarten full-day year in school prior to Year 1, few have common entry ages, and most use a variety of enrollment procedures. Emphasizes need for continuity to smooth transitions and manage stress…

  16. Measuring transit performance using data envelopment analysis

    Microsoft Academic Search

    Xuehao Chu; Gordon J. Fielding; Bruce W. Lamar

    1992-01-01

    Governmental agencies need to be able to assess the performance of transit agencies and to compare them with peer agencies. This assessment must measure not only how efficient the agency is in producing transit service, but also how effective it is in having that service consumed. This paper uses data envelopment analysis (DEA) to develop a single measure for the

  17. Transitions and Trajectories for Studies of Expertise

    ERIC Educational Resources Information Center

    Lajoie, Susanne P.

    2003-01-01

    The transition from student to expert professional can be accelerated when a trajectory for change is plotted and made visible to learners. Trajectories or paths toward expertise are domain specific and must first be documented and then used within instructional contexts to promote knowledge transitions. This article describes how models of…

  18. Earth and Venus transmission spectra during transit

    E-print Network

    Widemann, Thomas

    Earth and Venus transmission spectra during transit 3rd Europlanet workshop ­ 4th PHC/Sakura meeting: Venus as a transiting exoplanet March 5 ­ 7 2012, Paris, France A. García Muñoz (Formerly at) Instituto de Astrofísica de Canarias, La Laguna, Spain Frank P. Mills (Venus work) The Australian National

  19. Primary to Secondary Transition: The Tasmanian Experience.

    ERIC Educational Resources Information Center

    Tolbert, Sue

    2003-01-01

    Discusses transitioning students from primary to secondary language programs from a Tasmanian perspective. Identifies factors important in a smooth transition from the primary to secondary level, based on research, and outlines the Tasmanian issues and action plans and acknowledges the challenges that remain. (Author/VWL)

  20. Hysteresis and transition in swirling nonpremixed flames

    Microsoft Academic Search

    M. J. Tummers; A. W. Huebner; E. H. van Veen; K. Hanjalic; T. H. van der Meer

    2009-01-01

    Strongly swirling nonpremixed flames are known to exhibit a hysteresis when transiting from an attached long, sooty, yellow flame to a short lifted blue flame, and vice versa. The upward transition (by increasing the air and fuel flow rates) corresponds to a vortex breakdown, i.e. an abrupt change from an attached swirling flame (unidirectional or with a weak bluff-body recirculation),

  1. Interplay between chiral and deconfinement phase transitions

    E-print Network

    Fukun Xu; Tamal K. Mukherjee; Huan Chen; Mei Huang

    2011-01-15

    By using the dressed Polyakov loop or dual chiral condensate as an equivalent order parameter of the deconfinement phase transition, we investigate the relation between the chiral and deconfinement phase transitions at finite temperature and density in the framework of three-flavor Nambu--Jona-Lasinio (NJL) model. It is found that in the chiral limit, the critical temperature for chiral phase transition coincides with that of the dressed Polyakov loop in the whole $(T,\\mu)$ plane. In the case of explicit chiral symmetry breaking, it is found that the phase transitions are flavor dependent. For each flavor, the transition temperature for chiral restoration $T_c^{\\chi}$ is smaller than that of the dressed Polyakov loop $T_c^{{\\cal D}}$ in the low baryon density region where the transition is a crossover, and, the two critical temperatures coincide in the high baryon density region where the phase transition is of first order. Therefore, there are two critical end points, i.e, $T_{CEP}^{u,d}$ and $T_{CEP}^{s}$ at finite density. We also explain the feature of $T_c^{\\chi}=T_c^{\\cal D}$ in the case of 1st and 2nd order phase transitions, and $T_c^{\\chi}

  2. Middle Grades Transition Programs around the Globe

    ERIC Educational Resources Information Center

    Andrews, Colin; Bishop, Penny

    2012-01-01

    Transitions into and out of the middle grades can be challenging for many reasons. Students need to acclimate to new policies, practices, and buildings; teachers require accurate data about their new students' capacities; and families must navigate relationships with new personnel. All school transitions present different and, at times, puzzling…

  3. Phase transitions in the web of science

    NASA Astrophysics Data System (ADS)

    Phillips, J. C.

    2015-06-01

    The Internet age is changing the structure of science, and affecting interdisciplinary interactions. Publication profiles connecting mathematics with molecular biology and condensed matter physics over the last 40 years exhibit common phase transitions indicative of the critical role played by specific interdisciplinary interactions. The strengths of the phase transitions quantify the importance of interdisciplinary interactions.

  4. Understanding Secondary-Tertiary Transition in Mathematics

    ERIC Educational Resources Information Center

    Clark, Megan; Lovric, Miroslav

    2009-01-01

    In Clark and Lovric ("Suggestion for a theoretical model for secondary-tertiary transition in mathematics", "Math. Educ. Res. J." 20(2) (2008), pp. 25-37) we began developing a model for the secondary-tertiary transition in mathematics, based on the anthropological notion of a rite of passage. We articulated several reasons why we believe that the…

  5. Dynamic Transitions of Surface Tension Driven Convection

    E-print Network

    Henk Dijkstra; Taylan Sengul; Shouhong Wang

    2011-05-05

    We study the well-posedness and dynamic transitions of the surface tension driven convection in a three-dimensional (3D) rectangular box with non-deformable upper surface and with free-slip boundary conditions. It is shown that as the Marangoni number crosses the critical threshold, the system always undergoes a dynamic transition. In particular, two different scenarios are studied. In the first scenario, a single mode losing its stability at the critical parameter gives rise to either a Type-I (continuous) or a Type-II (jump) transition. The type of transitions is dictated by the sign of a computable non-dimensional parameter, and the numerical computation of this parameter suggests that a Type-I transition is favorable. The second scenario deals with the case where the geometry of the domain allows two critical modes which possibly characterize a hexagonal pattern. In this case we show that the transition can only be either a Type-II or a Type-III (mixed) transition depending on another computable non-dimensional parameter. We only encountered Type-III transition in our numerical calculations. The second part of the paper deals with the well-posedness and existence of global attractors for the problem.

  6. Financial Management for Transit: A Handbook.

    ERIC Educational Resources Information Center

    Heaselden, Mark; And Others

    This handbook is primarily intended to serve as a primer for transit system managers who have not had any formal financial education through college classes, professional development programs, or extensive on-the-job programs. The following topics are covered: financial planning techniques for transit (beginning the financial planning process,…

  7. Transition Strategies for Persons with Learning Disabilities.

    ERIC Educational Resources Information Center

    Michaels, Craig A., Ed.

    This collection of 10 papers focuses on the transition of students with learning disabilities from secondary education to employment, postsecondary education, independent living, and full social integration. The text concentrates on systemic transition problems that prevent successful communication, coordination, goal setting, and appropriate…

  8. Transitions in the Development of Giftedness

    ERIC Educational Resources Information Center

    Bonner, Fred A., II

    2005-01-01

    The purpose of this investigation was to assess the factors that lead to success in transitions of giftedness among a middle school student cohort. As part of the Yale University (PACE Center) Transitions in the Development of Giftedness evaluation plan, qualitative data were collected via a semistructured interview protocol. A total of 63…

  9. High School to Employment Transition: Contemporary Issues.

    ERIC Educational Resources Information Center

    Pautler, Albert J., Jr., Ed.

    This book contains 24 articles discussing the transition to employment for noncollege-bound youths in the United States. The book is organized around four major themes: background, reviews of research on students' transition experiences, employers' needs, and government efforts; analysis of programs, including successful ones in western Europe and…

  10. Transitioning from High School: A Postgraduate Study

    Microsoft Academic Search

    Krystal B Dunning

    2009-01-01

    Individuals transitioning from college face many decisions about their future. Making these decisions is not always easy for some. The role of all individuals involved in a high school is to prepare students for life after high school. A review of past postgraduate data was explored as well as programs that have been implemented to help students transition. A postgraduate

  11. The Transition out of High School

    Microsoft Academic Search

    K. W. Cullen; T. Baranowski

    1996-01-01

    LEARNING OUTCOME: To identify increased cancer risk behaviors during the transition out of high school.Low intakes of fruits and vegetables (F&V) are related to increased cancer risk Little research has focused on dietary behavior in the transition out of high school (HS), when diet is likely to change due to changes in school status, employment, living arrangements, income, and marital

  12. Transitions to School: Reframing Professional Relationships

    ERIC Educational Resources Information Center

    Boyle, Tess; Petriwskyj, Anne

    2014-01-01

    Systemic splits between pre-compulsory and compulsory early years education impact on transitions to school through discontinuities in children's experience. This paper presents data from a critical participatory action research project about transitions between pre-compulsory and compulsory early education schooling in Australia. The project…

  13. Transition Strategies to Ensure Active Student Engagement

    ERIC Educational Resources Information Center

    Korbel, Donna M.; McGuire, Joan M.; Banerjee, Manju; Saunders, Sue A.

    2011-01-01

    Transition into college for students with disabilities has been written about extensively over the past decade, due in part to legislative mandates implemented at the secondary level. With significant increases in the number of these students in the college population, a focus on their transition through college is imperative to improve retention…

  14. THE PROBLEM OF TRANSITION IN PALEONTOLOGY

    Microsoft Academic Search

    V. Ye. Ruzhentsev

    1964-01-01

    The author equates paleontology and phylogeny and discusses principles and problems of transitions found in the phylogentic approach to taxonomy. opics discussed include: subspecies and species (time needed for new species to become isolated is 500 to 1,000 years); the morphological exclusiveness of genera in the differential diagnoses of species, evolutionary patterns of transition in time, the biogenetic law (“Ontogenesis

  15. Building Bridges: Understanding Student Transition to University

    ERIC Educational Resources Information Center

    Briggs, A. R. J.; Clark, J.; Hall, I.

    2012-01-01

    This article explores challenges in ensuring effective student transition from school or college to university. It examines the complex liaison needed for students to progress to appropriate courses, settle into university life and succeed as higher education learners. Secondary data (international literature on transition and the formation of…

  16. Quantum manipulation on the Barium quadrupolar transition

    E-print Network

    Blatt, Rainer

    and stabilization of a new fiber laser system to ma- nipulate the Barium quadrupolar transition, with the aim . . . . . . . . . . . . . . . 55 6 Spectroscopy and sideband cooling on a single 138 Ba+ 58 6.1 Quantum jumps using the fiber laser . . . . . . . . . . . . .Quantum manipulation on the Barium quadrupolar transition A diploma thesis in physics submitted

  17. Thermodynamic glass transitions in three dimensional glasses

    NASA Astrophysics Data System (ADS)

    Berthier, Ludovic

    2015-03-01

    The physics associated to the glass transition controls the dramatic evolution of transport coefficients in systems as diverse as dense liquids, polymers, colloids, but also granular particles and active matter. The experimental liquid-glass transition in equilibrium fluids is characterized by several phenomenological crossovers, but glasses can form without crossing any sharp singularity. I will present multiple evidences suggesting that the glass formation process is underlied by equilibrium phase transitions. Combining numerical tools developed to study ordinary phase transitions to recent theoretical analytical progress I will demonstrate that studies of the glass transition have entered a new phase, where the relevant order parameter, thermodynamic fluctuations and phase transformations can be directly analysed in finite dimensional model glasses.

  18. Diagonal-transition quantum cascade detector

    SciTech Connect

    Reininger, Peter, E-mail: peter.reininger@tuwien.ac.at; Schwarz, Benedikt; Detz, Hermann; MacFarland, Don; Zederbauer, Tobias; Andrews, Aaron Maxwell; Schrenk, Werner; Strasser, Gottfried [Institute for Solid State Electronics and Center for Micro- and Nanostructures, Vienna University of Technology, Vienna (Austria); Baumgartner, Oskar; Kosina, Hans [Institute for Microelectronics, Vienna University of Technology, Vienna (Austria)

    2014-09-01

    We demonstrate the concept of diagonal transitions for quantum cascade detectors (QCD). Different to standard, vertical QCDs, here the active transition takes place between two energy levels in adjacent wells. Such a scheme has versatile advantages. Diagonal transitions generally yield a higher extraction efficiency and a higher resistance than vertical transitions. This leads to an improved overall performance, although the absorption strength of the active transition is smaller. Since the extraction is not based on resonant tunneling, the design is more robust, with respect to deviations from the nominal structure. In a first approach, a peak responsivity of 16.9?mA/W could be achieved, which is an improvement to the highest shown responsivity of a QCD for a wavelength of 8??m at room-temperature by almost an order of magnitude.

  19. Detecting Transits in Sparsely Sampled Surveys

    E-print Network

    Ford, H C; Hebb, L; Petro, L; Richmond, M; Rogers, J; 10.1063/1.3059062

    2009-01-01

    The small sizes of low mass stars in principle provide an opportunity to find Earth-like planets and "super-Earths" in habitable zones via transits. Large area synoptic surveys like Pan-STARRS and LSST will observe large numbers of low mass stars, albeit with widely spaced (sparse) time sampling relative to the planets' periods and transit durations. We present simple analytical equations that can be used to estimate the feasibility of a survey by setting upper limits to the number of transiting planets that will be detected. We use Monte Carlo simulations to find upper limits for the number of transiting planets that may be discovered in the Pan-STARRS Medium Deep and 3-pi surveys. Our search for transiting planets and M-dwarf eclipsing binaries in the SDSS-II supernova data is used to illustrate the problems (and successes) in using sparsely sampled surveys.

  20. Theory of conformational transitions of viral shells

    NASA Astrophysics Data System (ADS)

    Guérin, Thomas; Bruinsma, Robijn

    2007-12-01

    We propose a continuum theory for the conformational transitions of viral shells. Conformational transitions of viral shells, as encountered during viral maturation, are associated with a soft mode instability of the capsid proteins [F. Tama and C. L. Brooks, J. Mol. Biol. 345(2), 299 (2005)]. The continuum theory presented here is an adaptation of the Ginzburg-Landau theory of soft-mode structural phase transitions of solids to viral shells. The theory predicts that the conformational transitions are characterized by a pronounced softening of the shell elasticity in the critical region. We demonstrate that the thermodynamics of the conformational transition can be probed quantitatively by a micromechanical atomic force microscope study. The external force can drive a capsid into a state of phase coexistence characterized by a highly nonlinear force deformation curve.

  1. Cardiovascular Admissions, Readmissions, and Transitions of Care

    PubMed Central

    Chang, Anna Marie; Rising, Kristin L.

    2014-01-01

    Hospital 30-day readmissions have become a major priority for hospitals. Hospitals face penalties for excessive readmissions for acute myocardial infarction (AMI) and heart failure (HF). Thus, it is important for hospitals to understand the transitions of care that occur for both of these conditions, and what tools are available to guide the processes involved. A multi-disciplinary team including Emergency Medical Service providers, Emergency Medicine providers, cardiologists, hospitalists, pharmacists, nurses, case managers, and outpatient physicians can all be involved in the process of safely transitioning a patient between care settings. Small-scale studies in the geriatric population have shown improved transitions of care and decreased readmissions with these care teams. The emergency department is a key transition point for patients with AMI and HF, yet it is rarely identified and utilized as such in transitions of care interventions. Future research and implementation projects will need to refine and expand the role of the emergency department in the process. PMID:24678446

  2. Electric quadrupole transitions in x-ray spectra: 3d transition-metal oxides

    NASA Astrophysics Data System (ADS)

    Dobrodey, N. V.; Luniakov, Yu. V.

    1995-02-01

    The intensities of the electric quadrupole transitions in the x-ray spectra of the 3d-transition-metal monoxide diatomic molecules were calculated using the discrete variational method of the local-density approximation. The quadrupole transition intensities have been found to be negligible for the left-hand-side 3d metal oxides. It was shown that the electric quadrupole transitions can appreciably contribute to the MK?5 emission spectra of the right-hand-side 3d metal oxides, along with the dipole transitions.

  3. Exoplanet Transit Database. Reduction and processing of the photometric data of exoplanet transits

    NASA Astrophysics Data System (ADS)

    Poddaný, Stanislav; Brát, Luboš; Pejcha, Ond?ej

    2010-03-01

    We demonstrate the newly developed resource for exoplanet researchers - The Exoplanet Transit Database. This database is designed to be a web application and it is open for any exoplanet observer. It came on-line in September 2008. The ETD consists of three individual sections. One serves for predictions of the transits, the second one for processing and uploading new data from the observers. We use a simple analytical model of the transit to calculate the central time of transit, its duration and the depth of the transit. These values are then plotted into the observed-computed diagrams (O-C), that represent the last part of the application.

  4. Structural transitions in nanoscale systems

    NASA Astrophysics Data System (ADS)

    Yoon, Mina

    In this work I investigate three different materials: nanoscale carbon systems, ferrofluid systems, and molecular-electronic devices. In particular, my study is focused on the theoretical understanding of structural changes and the associated electronic, mechanical, and magnetic properties of these materials. To study the equilibrium packing of fullerenes in carbon nanotube peapods optimization techniques were applied. In agreement with experimental measurements, my results for nanotubes containing fullerenes with 60--84 atoms indicate that the axial separation between the fullerenes is smaller than in the bulk crystal. The reduction of the inter-fullerene distance and also the structural relaxation of fullerenes result from a large internal pressure within the peapods. This naturally induced "static" pressure may qualify nanotubes as nanoscale autoclaves for chemical reactions. Combining total energy calculations with a search of phase space, I investigated the microscopic fusion mechanism of C60 fullerenes. I show that the (2+2) cycloaddition reaction, a necessary precursor for fullerene fusion, can be accelerated inside a nanotube. Fusion occurs along the minimum energy path as a finite sequence of Stone-Wales (SW) transformations. A detailed analysis of the transition states shows that Stone-Wales transformations are multi-step processes. I propose a new microscopic mechanism to explain the unusually fast fusion process of carbon nanotubes. The detailed pathway for two adjacent (5, 5) nanotubes to gradually merge into a (10, 10) tube, and the transition states have been identified. The propagation of the fused region is energetically favorable and proceeds in a morphology reminiscent of a Y-junction via a so called zipper mechanism, involving only SW bond rearrangements with low activation barriers. Using density functional theory, the equilibrium structure, stability, and electronic properties of nanostructured, hydrogen terminated diamond fragments have been studied. Such diamondoids can enter spontaneously into carbon nanotubes where polymerization of diamondoids is favourable. I studied the equilibrium structure of large but finite aggregates of magnetic dipoles, modeling a colloidal suspension of magnetite particles in a ferrofluid. With increasing system size, the structural motif evolves from chains and rings to multi-chain and multi-ring assemblies. These structural changes depend on external parameters and result from a competition between various energy terms, which can be described analytically within a continuum approximation. (Abstract shortened by UMI.)

  5. Spin transition in Fe-bearing perovskite

    NASA Astrophysics Data System (ADS)

    Caracas, R.

    2012-04-01

    The Earth's lower mantle, which is the largest part by volume of our planet, is mainly formed of Fe- and Al- bearing MgSiO3 perovskite (pv). The Fe-component exhibits a spin transition under pressure whose nature and outcome is still a matter of debate. Here we are using lattice dynamical calculations based on density functional perturbation theory to disentangle a part of its complex phase diagram and the spin behavior. To do this we investigate the dynamic stability of Pbnm FeSiO3 pv and show the existence of unstable phonon modes. We track the eigen-displacements of the phonons modes to find low-spin and intermediate spin states. On solid-state physical basis we explore a set of hypothetical structures with various spin configurations and considerably lower enthalpy than the parent orthorhombic Pbnm structure. We show that the spin evolves along a high-spin to mixed high- and intermediate spin to low-spin transition sequence. Based on numerical results from first-principles calculations, we show that the spin transitions can be observed experimentally in X-ray diffraction and Raman measurements. New diffraction peaks form during the spin transition, which are explained by the associated symmetry breaking. Certain observable Raman peaks exhibit a shift at the transition; the Grueneisen parameters of certain few modes are affected by the transition. The spin transition affects the seismic anisotropy pattern of perovskite. However it does not affect the elastic moduli and the bulk seismic wave velocities are weakly affected by the spin transition. [1]. These signatures are detectable by seismic observations and they need to be taken into account in tomographic studies of the Earth's lower mantle. Finally we show that the iron spin transition develops also in compressed glasses, but over a broad pressure range. More interestingly this transition can pass by an intermediate spin state configuration. [1] Caracas, Mainprice, and Thomas (2010) Geophys. Res. Lett. 37, L13309.

  6. ESTIMATION OF STATEWIDE URBAN PUBLIC TRANSIT BENEFITS IN TENNESSEE

    Microsoft Academic Search

    Frank Southworth; David Vogt; T R Curlee

    2004-01-01

    A comprehensive transit benefits assessment procedure is described as applied to each of the 12 urban public transit operating districts in the state of Tennessee. A multiple-branch benefits assessment tree is developed around transit use benefits and transit supply benefits, the former emphasizing the costs of lost mobility in the absence of current transit services and the latter reflecting the

  7. New graduate nurses in transition: a review of transition programmes and transition experiences within mental health care.

    PubMed

    Tingleff, Ellen Boldrup; Gildberg, Frederik Alkier

    2014-12-01

    Research on experiences of transition into mental health-care roles seems sparse, but it is vital in order to produce a comprehensive understanding of the transition into mental health-care roles and to serve as a foundation for future research and development. The aim of the present study was to review existing research literature, and in doing so, investigate transition programmes for new graduate nurses (NGN) into mental health care, and their experiences of role transition and evaluations of participation in transition programmes. The literature review spans literature published after the year 2000. The literature search was conducted using the following databases: CINAHL, Psychology and Behavioral Sciences Collection, PsycINFO, and Pubmed. Search results consisting of 14 articles were analysed using thematic analysis. Results from the analysis showed four overall themes: nursing education, transition programmes and evaluations, working environment, and the NGN role. We conclude that it is not possible to produce a comprehensive understanding specifically concerning the transition programmes for NGN into mental health care, and that further research is necessary due to the limitations of this review. PMID:25606623

  8. Evolution of a Transition State

    PubMed Central

    Miller, Stephen P.; Gonçalves, Susana; Matias, Pedro M.; Dean, Antony M.

    2015-01-01

    An active site lysine essential to catalysis in isocitrate dehydrogenase (IDH) is absent from related enzymes. As all family members catalyze the same oxidative ?-decarboxylation at the 2R-malate core common to their substrates, it seems odd that an amino acid essential to one is not found in all. Ordinarily, hydride transfer to a nicotinamide C4 neutralizes the positive charge at N1 directly. In IDH the negatively charged C4-carboxylate of isocitrate stabilizes the ground state positive charge on the adjacent nicotinamide N1, opposing hydride transfer. The critical lysine is poised to stabilize – and perhaps even protonate – an oxyanion formed on the nicotinamide 3-carboxamide, thereby enabling the hydride to be transferred while the positive charge at N1 is maintained. IDH may catalyze the same overall reaction as other family members, but dehydrogenation proceeds through a distinct, though related, transition state. Partial activation of lysine mutants by K+ and NH4+ represents a throwback to the primordial state of the first substrate promiscuous family member. PMID:24797066

  9. Piperazine pivoted transition metal dithiocarbamates

    NASA Astrophysics Data System (ADS)

    Khan, Sadaf; Nami, Shahab A. A.; Siddiqi, K. S.

    2008-03-01

    A quadridentate ligand disodium bis(2,2'-dithiopiperazinato-2,2'-diamino diethylamine) Na 2L 2 and its self assembled transition metal complexes of the type, M 2(L 2) 2 {M = Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II)} have been reported. The piperazine pivoted homodinuclear complexes have been characterized by a range of spectral, thermal, microanalytical and conductometric techniques. On the basis of IR and 1HNMR data a symmetrical bidentate coordination of the dithiocarbamato moiety has been observed in all the cases. The TGA profile of the ligand exhibits two stage thermolytic pattern although the complexes decompose in three steps, respectively. Metal sulfide is found to be the end product. The formation of homodinuclear complexes has been ascertained on the basis of FAB mass spectral data and a probable fragmentation pattern has been proposed. On the basis of UV-visible spectroscopic results and room temperature magnetic moment data a tetrahedral geometry has been proposed for all the complexes except for the Ni(II) and Cu(II) which are found to be square-planar.

  10. Los Angeles Mass Transit Strike

    NSDL National Science Digital Library

    Beginning on Saturday, September 16, 2000, the drivers of the Los Angeles city buses launched a strike, stopping the 2,000 buses, subway, and rail lines that cover the 1,400 square miles of Los Angeles County, and stranding nearly half a million bus riders. The 4,300 members of the United Transportation Union (UTU) are on strike over wages and overtime. The Mass Transit Authority (MTA) of Los Angeles will face a $438 million deficit by 2010 if it does not manage to cut costs. Rather than raise fares, the MTA suggested cutting the cost of drivers's overtime pay by fifteen percent over the next three years, for a saving of $23 million. To do this, the MTA proposed that 400 drivers accept a four-day-a-week work schedule, in which they would be on duty twelve hours a day, but would only be paid for ten hours. Overtime would start only after twelve hours. The strike has already proven itself difficult for the people of Los Angeles. Traffic increased nearly five percent, and those Los Angelenos who depend on public transportation to get to work and school, have been forced to walk, carpool, or ride bikes. According to the MTA, 68 percent of MTA riders have household incomes under $15,000 a year. Talks between the UTU and the MTA were to have resumed on Tuesday morning.

  11. Student-Directed Transition Planning: Increasing Student Knowledge and Self-Efficacy in the Transition Planning Process

    ERIC Educational Resources Information Center

    Woods, Lee L.; Sylvester, Lorraine; Martin, James E.

    2010-01-01

    This study examined the effectiveness of a new school to adult life transition planning lesson package titled "Student-Directed Transition Planning". The "Student-Directed Transition Planning" lessons teach transition terms and concepts to provide a means to increase self-determination skills and student participation in transition IEP…

  12. Transitions in pressure collapsed clathrate hydrates.

    PubMed

    Andersson, Ove; Nakazawa, Yasuhiro

    2015-03-01

    Type II clathrate hydrates (CHs), or ice clathrates, are inclusion compounds in which a hydrogen-bonded cage-like structure of H2O accommodates molecules of suitable size, known as "guest molecules". CHs have similar local geometrical arrangements of the hydrogen-bonded water network as ice and both are known to collapse to amorphous states on isothermal pressurization at temperatures below about 140 K. Moreover, the collapsed CH states undergo a glass, or glass-like, transition at 140 K on heating at 1 GPa, which is identical to that of collapsed ice, or high density amorphous ice. Here we use thermal conductivity and dielectric measurements to study the transition behavior of two type II CHs with tetrahydrofuran and 1,3 dioxolane, respectively, as guest molecules. After their collapsed states have been heated to well above the glass transition at 1 GPa, we find transitions corresponding to the high to low density amorphous ice transition of ice with only slightly shifted temperature-pressure (T-p) coordinates compared to those of pure water. Thus, collapsed CHs show the same transition behaviors as cold water, which provide the basis for the model that explains the unusual temperature and pressure behaviors of water's properties in terms of two distinct types of liquid water. Collapsed CHs are, however, more stable than collapsed ice and can therefore be studied in a wider T-p interval. The results suggest sluggish homogenizing and phase separation processes, which affect the transition behaviors of collapsed CHs. PMID:25686530

  13. Unjamming and jamming transitions of granular avalanches

    NASA Astrophysics Data System (ADS)

    Zhang, Jie; Wang, Ziwei

    2014-03-01

    Study of the jamming transitions of granular materials has become an active field of research in recent years. A closely related inverse process is the unjamming transition, where granular systems may suddenly lose rigidity and start to flow freely. Understanding such a process is of crucial implication towards the understanding of natural disasters such as snow avalanches, landslides and earthquakes. Recent work by Banigan and colleagues (Nature Physics 2013) has provided a new perspective in the study of unjamming and jamming transitions by applying nonlinear dynamical methods. To test their proposition experimentally, we have designed a rotating drum filled with bidisperse photo-elastic disks to create particle avalanches. In unjamming transition, Lyapunov vector and velocity fields are indeed strongly correlated in spatial domain, whereas in jamming transition no such a strong correlation is observed. The Lyapunov exponents are positive in unjamming transition and negative in jamming transition. In addition, the total stress variation, kinetic energy, and non-affine motion of particles all show strong correlations in the time domain during avalanches. Their spatial correlations have also been analyzed.

  14. Overview of escalator applications in rail transit

    NASA Technical Reports Server (NTRS)

    Deshpande, G.; Rubenstein, L.

    1980-01-01

    The difference in operating environment and in construction between escalators in transit and nontransit use, the impact of recent escalator innovations, and areas which could benefit from urban mass transportation administration sponsored research and development are determined. Several factors causing a more severe transit escalator operating environment are identified. There are no significant design differences between transit and nontransit escalators. Recent innovations that have affected performance and cost include outdoor escalators, extra flat steps at both landings, and modular escalators. Data were collected by interviews at transit agencies. Long term, unscheduled, escalator maintenance records were available for analysis from one property. A description of escalator operating principles is provided. Transit represents less than 5% of the U.S. escalator market. Transit agencies have limited leverage on escalator industry practices. A substantial impact on transit escalator cost and performance can be achieved by research identifying when and how to apply and specify several of the more recent innovations. Purchase of escalators under long term (25 year) maintenance contracts is one method that has been used to promote escalators manufactured for minimum life cycle cost.

  15. Simplified lattice model for polypeptide fibrillar transitions

    NASA Astrophysics Data System (ADS)

    Xiao, Xuhui; Wu, Ming-Chya

    2014-10-01

    Polypeptide fibrillar transitions are studied using a simplified lattice model, modified from the three-state Potts model, where uniform residues as spins, placed on a cubic lattice, can interact with neighbors to form coil, helical, sheet, or fibrillar structure. Using the transfer matrix method and numerical calculations, we analyzed the partition function and construct phase diagrams. The model manifests phase transitions among coil, helix, sheet, and fibril through parameterizing bond coupling energy ?h,?s,?f, structural entropies sh,ss,sf of helical, sheet, and fibrillar states, and number density ?. The phase diagrams show the transition sequence is basically governed by ?h, ?s, and ?f, while the transition temperature is determined by the competition among ?h, ?s, and ?f, as well as sh, ss, sf, and ?. Furthermore, the fibrillation is accompanied with an abrupt phase transition from coil, helix, or sheet to fibril even for short polypeptide length, resembling the feature of nucleation-growth process. The finite-size effect in specific heat at transitions for the nonfibrillation case can be described by the scaling form of lattice model. With rich phase-transition properties, our model provides a useful reference for protein aggregation experiments and modeling.

  16. Phase transitions in the early universe

    NASA Astrophysics Data System (ADS)

    Wainwright, Carroll L.

    I explore the theory and computation of early-Universe finite-temperature phase transitions involving scalar fields. I focus primarily on the electroweak phase transition, but some of the methods I develop are applicable to any scalar-field cosmological phase transition (such as the computation of the lifetime of zero-temperature metastable vacua). I begin by examining phase transition thermodynamics with many extra coupled degrees of freedom, finding that such transitions have the potential to produce large amounts of entropy and can significantly dilute the concentration of thermal relic species (e.g., dark matter). I then detail a novel algorithm for calculating instanton solutions with multiple dynamic scalar fields, and present a computational package which implements the algorithm and computes the finite-temperature phase structure. Next, I discuss theoretical and practical problems of gauge dependence in finite-temperature effective potentials, using the Abelian Higgs and Abelian Higgs plus singlet models to show the severity of the problem. Finally, I apply the aforementioned algorithm to the electroweak phase transition in the next-to-minimal supersymmetric standard model (NMSSM). My collaborators and I find viable regions of the NMSSM which contain a strongly first-order phase transition and large enough CP violation to support electroweak baryogenesis, evade electric dipole moment constraints, and provide a dark matter candidate which could produce the observed 130 GeV gamma-ray line observed in the galactic center by the Fermi Gamma-ray Space Telescope.

  17. Quantitative measurement of feline colonic transit

    SciTech Connect

    Krevsky, B.; Somers, M.B.; Maurer, A.H.; Malmud, L.S.; Knight, L.C.; Fisher, R.S.

    1988-10-01

    Colonic transit scintigraphy, a method for quantitatively evaluating the movement of the fecal stream in vivo, was employed to evaluate colonic transit in the cat. Scintigraphy was performed in duplicate in five cats and repeated four times in one cat. After instillation of an 111In marker into the cecum through a surgically implanted silicone cecostomy tube, colonic movement of the instillate was quantitated for 24 h using gamma scintigraphy. Antegrade and retrograde motion of radionuclide was observed. The cecum and ascending colon emptied rapidly, with a half-emptying time of 1.68 +/- 0.56 h (mean +/- SE). After 24 h, 25.1 +/- 5.2% of the activity remained in the transverse colon. The progression of the geometric center was initially rapid, followed later by a delayed phase. Geometric center reproducibility was found to be high when analyzed using simple linear regression (slope = 0.92; r = 0.73; P less than 0.01). Atropine (0.1 mg/kg im) was found to delay cecum and ascending colon emptying and delay progression of the geometric center. These results demonstrate both 1) the ability of colonic transit scintigraphy to detect changes in transit induced by pharmacological manipulation and 2) the fact that muscarinic blockade inhibits antegrade transit of the fecal stream. We conclude that feline colonic transit may be studied in a quantitative and reproducible manner with colonic transit scintigraphy.

  18. Microgravity Two-Phase Flow Transition

    NASA Technical Reports Server (NTRS)

    Parang, M.; Chao, D.

    1999-01-01

    Two-phase flows under microgravity condition find a large number of important applications in fluid handling and storage, and spacecraft thermal management. Specifically, under microgravity condition heat transfer between heat exchanger surfaces and fluids depend critically on the distribution and interaction between different fluid phases which are often qualitatively different from the gravity-based systems. Heat transfer and flow analysis in two-phase flows under these conditions require a clear understanding of the flow pattern transition and development of appropriate dimensionless scales for its modeling and prediction. The physics of this flow is however very complex and remains poorly understood. This has led to various inadequacies in flow and heat transfer modeling and has made prediction of flow transition difficult in engineering design of efficient thermal and flow systems. In the present study the available published data for flow transition under microgravity condition are considered for mapping. The transition from slug to annular flow and from bubbly to slug flow are mapped using dimensionless variable combination developed in a previous study by the authors. The result indicate that the new maps describe the flow transitions reasonably well over the range of the data available. The transition maps are examined and the results are discussed in relation to the presumed balance of forces and flow dynamics. It is suggested that further evaluation of the proposed flow and transition mapping will require a wider range of microgravity data expected to be made available in future studies.

  19. Game Theory and Topological Phase Transition

    E-print Network

    Tieyan Si

    2008-03-29

    Phase transition is a war game. It widely exists in different kinds of complex system beyond physics. Where there is revolution, there is phase transition. The renormalization group transformation, which was proved to be a powerful tool to study the critical phenomena, is actually a game process. The phase boundary between the old phase and new phase is the outcome of many rounds of negotiation between the old force and new force. The order of phase transition is determined by the cutoff of renormalization group transformation. This definition unified Ehrenfest's definition of phase transition in thermodynamic physics. If the strategy manifold has nontrivial topology, the topological relation would put a constrain on the surviving strategies, the transition occurred under this constrain may be called a topological one. If the strategy manifold is open and noncompact, phase transition is simply a game process, there is no table for topology. An universal phase coexistence equation is found, it sits at the Nash equilibrium point. Inspired by the fractal space structure demonstrated by renormalization group theory, a conjecture is proposed that the universal scaling law of a general phase transition in a complex system comes from the coexistence equation around Nash equilibrium point. Game theory also provide us new understanding to pairing mechanism and entanglement in many body physics.

  20. Mass transit infrastructure and urban health.

    PubMed

    Zimmerman, Rae

    2005-03-01

    Mass transit is a critical infrastructure of urban environments worldwide. The public uses it extensively, with roughly 9 billion mass transit trips occurring annually in the United States alone according to the U.S. Department of Transportation data. Its benefits per traveler include lower emissions of air pollutants and energy usage and high speeds and safety records relative to many other common modes of transportation that contribute to human health and safety. However, mass transit is vulnerable to intrusions that compromise its use and the realization of the important benefits it brings. These intrusions pertain to physical conditions, security, external environmental conditions, and equity. The state of the physical condition of transit facilities overall has been summarized in the low ratings the American Society of Civil Engineers gives to mass transit, and the large dollar estimates to maintain existing conditions as well as to bring on new improvements, which are, however, many times lower than investments estimated for roadways. Security has become a growing issue, and numerous incidents point to the potential for threats to security in the US. External environmental conditions, such as unexpected inundations of water and electric power outages also make transit vulnerable. Equity issues pose constraints on the use of transit by those who cannot access it. Transit has shown a remarkable ability to rebound after crises, most notably after the September 11, 2001 attacks on the World Trade Center, due to a combination of design and operational features of the system. These experiences provide important lessons that must be captured to provide proactive approaches to managing and reducing the consequences of external factors that impinge negatively on transit. PMID:15738338

  1. 7 CFR 51.1309 - Condition after storage or transit.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 2011-01-01 false Condition after storage or transit. 51.1309 Section 51.1309...Standards for Winter Pears 1 Condition After Storage Or Transit § 51.1309 Condition after storage or transit. Decay, scald or other...

  2. 7 CFR 51.1309 - Condition after storage or transit.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 2010-01-01 false Condition after storage or transit. 51.1309 Section 51.1309...Standards for Winter Pears 1 Condition After Storage Or Transit § 51.1309 Condition after storage or transit. Decay, scald or other...

  3. 7 CFR 51.1268 - Condition after storage or transit.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 2011-01-01 false Condition after storage or transit. 51.1268 Section 51.1268...Summer and Fall Pears 1 Condition After Storage Or Transit § 51.1268 Condition after storage or transit. Decay, scald, or...

  4. 23 CFR 810.204 - Application by mass transit authority.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Application by mass transit authority. 810.204 Section...TRANSPORTATION PUBLIC TRANSPORTATION MASS TRANSIT AND SPECIAL USE HIGHWAY PROJECTS...Highway Rights-of-Way Available for Mass Transit Projects § 810.204...

  5. 23 CFR 810.204 - Application by mass transit authority.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 false Application by mass transit authority. 810.204 Section...TRANSPORTATION PUBLIC TRANSPORTATION MASS TRANSIT AND SPECIAL USE HIGHWAY PROJECTS...Highway Rights-of-Way Available for Mass Transit Projects § 810.204...

  6. 23 CFR 810.204 - Application by mass transit authority.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 false Application by mass transit authority. 810.204 Section...TRANSPORTATION PUBLIC TRANSPORTATION MASS TRANSIT AND SPECIAL USE HIGHWAY PROJECTS...Highway Rights-of-Way Available for Mass Transit Projects § 810.204...

  7. 23 CFR 810.204 - Application by mass transit authority.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Application by mass transit authority. 810.204 Section...TRANSPORTATION PUBLIC TRANSPORTATION MASS TRANSIT AND SPECIAL USE HIGHWAY PROJECTS...Highway Rights-of-Way Available for Mass Transit Projects § 810.204...

  8. 23 CFR 810.204 - Application by mass transit authority.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Application by mass transit authority. 810.204 Section...TRANSPORTATION PUBLIC TRANSPORTATION MASS TRANSIT AND SPECIAL USE HIGHWAY PROJECTS...Highway Rights-of-Way Available for Mass Transit Projects § 810.204...

  9. Introduction to Network Science 13 Clustering Coefficient and Transitivity

    E-print Network

    Safro, Ilya

    Introduction to Network Science 13 Clustering Coefficient and Transitivity #12;Introduction to Network Science 14 [BE] "Network Analysis" Clustering Coefficient and Transitivity #12;Introduction to Network Science 15 Clustering Coefficient and Transitivity #12;Introduction to Network Science 16 Homework

  10. 47 CFR 27.20 - Digital television transition education reports.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Digital television transition education reports. 27...Applications and Licenses § 27.20 Digital television transition education reports...the transition from analog broadcast television service to digital broadcast...

  11. 47 CFR 27.20 - Digital television transition education reports.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Digital television transition education reports. 27...Applications and Licenses § 27.20 Digital television transition education reports...the transition from analog broadcast television service to digital broadcast...

  12. 47 CFR 27.20 - Digital television transition education reports.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Digital television transition education reports. 27...Applications and Licenses § 27.20 Digital television transition education reports...the transition from analog broadcast television service to digital broadcast...

  13. Collective migration Inertial migration Transition to turbulence Particulate flow

    E-print Network

    Collective migration Inertial migration Transition to turbulence Particulate flow ´Elisabeth;Collective migration Inertial migration Transition to turbulence Particulate and granular flows Particulate flow IUSTI - CNRS - Polytech'Marseille #12;Collective migration Inertial migration Transition

  14. Nanoscale Thermotropic Phase Transitions Enhance Photothermal Microscopy Signals

    E-print Network

    Boyer, Edmond

    1 Nanoscale Thermotropic Phase Transitions Enhance Photothermal Microscopy Signals A. Nicholas G phase transition, we demonstrate a 40-fold signal-to-noise ratio enhancement for gold nanoparticles microscopy, nanoparticles, thermotropic phase transition, liquid crystals, single molecule detection. #12

  15. Transition region modeling for compressible flow

    NASA Astrophysics Data System (ADS)

    Chang, C.-L.; Singer, B. A.; Dinavahi, S. P. G.; El-Hady, N. M.; Pruett, C. D.; Harris, J. E.; Streett, C. L.; Zang, T. A.; Wilcox, D. C.

    1992-12-01

    The ongoing effort at NASA Langley Research Center aimed at developing transitional zone models for Reynolds-averaged Navier-Stokes calculations is described. Results from three models that we have examined - two zero-equation models and a two-equation model of the k-omega type - are presented for high-speed flows. The use of analytical and computational tools to provide guidance and to provide the transitional flow-field data bases necessary to develop such models is discussed. Some results from validation of these tools are given; qualitative comparisons between modeled and theoretical/computational representations of the transitional zone are provided.

  16. Reentrant spin-flop transition in nanomagnets

    NASA Astrophysics Data System (ADS)

    Crescioli, Mattia; Politi, Paolo; Vaia, Ruggero

    2014-09-01

    Antiferromagnetic chains with an odd number of spins are known to undergo a transition from an antiparallel to a spin-flop configuration when subjected to an increasing magnetic field. We show that in the presence of an anisotropy favoring alignment perpendicular to the field, the spin-flop state appears for both weak and strong fields, the antiparallel state appearing for intermediate fields. Both transitions are second order, the configuration varying continuously with the field intensity. Such reentrant transition is robust with respect to quantum fluctuations and it might be observed in different types of nanomagnets.

  17. Switchable thermal antenna by phase transition

    E-print Network

    Ben-Abdallah, Philippe; Besbes, Mondher

    2013-01-01

    We introduce a thermal antenna which can be actively switched by phase transition. The source makes use of periodically patterned vanadium dioxide, a metal-insulator phase transition material which supports a surface phonon-polariton (SPP) in the infrared range in its crystalline phase. Using electrodes properly registred with respect to the pattern, the phase transition of VO2 can be localy triggered within few microseconds and the SPP can be diffracted making the thermal emission highly directionnal. This switchable antenna could find broad applications in the domain of active thermal coatings or in those of infrared spectroscopy and sensing.

  18. Transition region modeling for compressible flow

    NASA Technical Reports Server (NTRS)

    Chang, C.-L.; Singer, B. A.; Dinavahi, S. P. G.; El-Hady, N. M.; Pruett, C. D.; Harris, J. E.; Streett, C. L.; Zang, T. A.; Wilcox, D. C.

    1992-01-01

    The ongoing effort at NASA Langley Research Center aimed at developing transitional zone models for Reynolds-averaged Navier-Stokes calculations is described. Results from three models that we have examined - two zero-equation models and a two-equation model of the k-omega type - are presented for high-speed flows. The use of analytical and computational tools to provide guidance and to provide the transitional flow-field data bases necessary to develop such models is discussed. Some results from validation of these tools are given; qualitative comparisons between modeled and theoretical/computational representations of the transitional zone are provided.

  19. Experience with split transition lattices at RHIC

    SciTech Connect

    Montag, C.; Tepikian, S.; Blaskiewicz, M.; Brennan, J.M.

    2010-05-23

    During the acceleration process, heavy ion beams in RHIC cross the transition energy. When RHIC was colliding deuterons and gold ions during Run-8, lattices with different integer tunes were used for the two rings. This resulted in the two rings crossing transition at different times, which proved beneficial for the 'Yellow' ring, the RF system of which is slaved to the 'Blue' ring. For the symmetric gold-gold run in FY2010, lattices with different transition energies but equal tunes were implemented. We report the optics design concept as well as operational experience with this configuration.

  20. Experimental characterization of layer thinning transitions

    NASA Astrophysics Data System (ADS)

    Pankratz, S.; Johnson, P. M.; Nguyen, H. T.; Huang, C. C.

    1998-09-01

    The layer thinning transitions in free-standing films of several liquid-crystal compounds containing different combinations of flexible tails have been systematically investigated. The results clearly indicate that fluorination of liquid-crystal compounds plays an essential role in the layer-by-layer thinning transitions of free-standing films above the bulk smectic-A-isotropic transition temperature TAI. The surface ordering effects of these fluorinated compounds above TAI is contrasted with recent x-ray results that suggest surface disorder below TAI in a fluorinated liquid-crystal compound.

  1. Periodic transition on an axial compressor stator: Incidence and clocking effects. Part 2: Transition onset predictions

    SciTech Connect

    Solomon, W.J. [General Electric Aircraft Engines, Cincinnati, OH (United States); Walker, G.J.; Hughes, J.D. [Univ. of Tasmania, Hobart (Australia). School of Engineering

    1999-07-01

    Transition onset observations from a 1.5-stage axial compressor outlet stator presented in Part 1 of this paper are compared with the predictions of conventional transition correlations applied in a quasi-steady manner. The viscous/inviscid interaction code MISES is used to predict the blade surface pressure distributions, and boundary layer development. The temporal variation in transition onset is then predicted using ensemble-averaged free-stream turbulence data from the compressor measurements. This simple procedure captures most significant features of the complex transition process on the compressor, and is clearly superior to fixed transition models based on long-term average free-stream turbulence levels. Parallel computations for both natural and bypass transition modes indicate that the natural transition mode tends to dominate on the compressor. This is at variance with turbine airfoil experience, where bypass transition is clearly more important. Comparison of prediction and experiment highlights the significance of leading edge potential flow interactions in promoting periodic wake-induced transition. Viscous/inviscid interactions in the neighborhood of transition can also have an important influence on boundary layer stability and separation phenomena.

  2. A stochastic model dissects cell states in biological transition processes

    E-print Network

    Armond, Jonathan W.

    Many biological processes, including differentiation, reprogramming, and disease transformations, involve transitions of cells through distinct states. Direct, unbiased investigation of cell states and their transitions ...

  3. Does Sex Induce a Phase Transition?

    E-print Network

    de Oliveira, P M C; Stauffer, D; Cebrat, S; Pekalski, A; 10.1140/epjb/e2008-00229-3

    2009-01-01

    We discovered a dynamic phase transition induced by sexual reproduction. The dynamics is a pure Darwinian rule with both fundamental ingredients to drive evolution: 1) random mutations and crossings which act in the sense of increasing the entropy (or diversity); and 2) selection which acts in the opposite sense by limiting the entropy explosion. Selection wins this competition if mutations performed at birth are few enough. By slowly increasing the average number m of mutations, however, the population suddenly undergoes a mutational degradation precisely at a transition point mc. Above this point, the "bad" alleles spread over the genetic pool of the population, overcoming the selection pressure. Individuals become selectively alike, and evolution stops. Only below this point, m < mc, evolutionary life is possible. The finite-size-scaling behaviour of this transition is exhibited for large enough "chromosome" lengths L. One important and surprising observation is the L-independence of the transition curv...

  4. Quantum phase transition in a graphene model

    NASA Astrophysics Data System (ADS)

    Hands, Simon; Strouthos, Costas

    2009-03-01

    We present results for the equation of state of a graphene-like model in an effort to understand the properties of its quantum phase transition. The Nf fermion species interact through a three dimensional instantaneous Coulomb potential. Since there are no reliable analytical tools that work for all values of Nf and the coupling constant g, we rely on Monte Carlo simulations to calculate the critical properties of the model near the phase transition. We consider the four-component formulation for the fermion fields, which arises naturally as the continuum limit of the staggered fermion construction in (2 + 1) dimensions. In the limit of infinitely strong Coulomb interaction, the system undergoes a quantum phase transition at a critical number of fermion species Nfc approx 4.7. We also calculate the values of the critical exponents at the quantum phase transition.

  5. A principal in transition: an autoethnography 

    E-print Network

    Dethloff, Carl Henry

    2007-04-25

    This research represents a highly personalized account of the complexities, interpretations, and reflections of a principal in transition from one elementary school to another elementary school in the same district. Using ...

  6. 12 CFR 3.3 - Transitional rules.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...rules. 3.3 Section 3.3 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY MINIMUM CAPITAL RATIOS; ISSUANCE OF DIRECTIVES Authority and Definitions § 3.3 Transitional rules. Intangible assets, other...

  7. Phase transition phenomenon: A compound measure analysis

    NASA Astrophysics Data System (ADS)

    Kang, Bo Soo; Park, Chanhi; Ryu, Doojin; Song, Wonho

    2015-06-01

    This study investigates the well-documented phenomenon of phase transition in financial markets using combined information from both return and volume changes within short time intervals. We suggest a new measure for the phase transition behaviour of markets, calculated as a return distribution conditional on local variance in volume imbalance, and show that this measure successfully captures phase transition behaviour under various conditions. We analyse the intraday trade and quote dataset from the KOSPI 200 index futures, which includes detailed information on the original order size and the type of each initiating investor. We find that among these two competing factors, the submitted order size yields more explanatory power on the phenomenon of market phase transition than the investor type.

  8. Multiplicative Noise and Second Order Phase Transitions

    NASA Astrophysics Data System (ADS)

    Manor, Alon; Shnerb, Nadav M.

    2009-07-01

    The scale-free distribution of cluster sizes in continuous phase transitions is linked to the law of proportional effect. A numerical study of a two-dimensional Ising model suggests that a cluster size undergoes a multiplicative birth-death process. At the transition the ratio between birth and death rates approaches unity for large clusters, and the resulting steady state shows a power-law behavior. The percolation dynamic, on the other hand, yields a geometric phase transition without ergodicity breaking, where large-scale merging and splitting of clusters dominate the distribution. Instead of short-range birth-death jumps, the percolation transition is characterized by Lévi flights along the cluster-size axis.

  9. Transitions from Formal Education to the Workplace

    ERIC Educational Resources Information Center

    Olson, Joann S.

    2014-01-01

    This chapter frames the transition to adulthood in the context of the moving from formal educational settings to the often less-structured learning that occurs in workplace settings. Although schooling may end, learning continues.

  10. Twist transition of nematic hyperbolic hedgehogs.

    PubMed

    James, Richard; Fukuda, Jun-ichi

    2014-04-01

    Stability of an idealized hyperbolic hedgehog in a nematic liquid crystal against a twist transition is investigated by extending the methodology of Rüdinger and Stark [Liq. Cryst. 26, 753 (1999)], where the hedgehog is confined between two concentric spheres. In the ideal hyperbolic-hedgehog the molecular orientation is assumed to rotate proportionally with respect to the inclination angle, ? (and in the opposite sense). However, when splay, k11, and bend, k33, moduli differ this proportionality is lost and the liquid crystal deforms relative to the ideal with bend and splay. Although slight, these deformations are shown to significantly shift the transition if k11/k33 is small. By increasing the degree of confinement the twist transition can be inhibited, a characteristic both hyperbolic and radial hedgehogs have in common. The twist transition of a hyperbolic defect that accompanies a particle is found to be well predicted by the earlier stability analysis of a thick shell. PMID:24827263

  11. Twist transition of nematic hyperbolic hedgehogs

    NASA Astrophysics Data System (ADS)

    James, Richard; Fukuda, Jun-ichi

    2014-04-01

    Stability of an idealized hyperbolic hedgehog in a nematic liquid crystal against a twist transition is investigated by extending the methodology of Rüdinger and Stark [Liq. Cryst. 26, 753 (1999), 10.1080/026782999204840], where the hedgehog is confined between two concentric spheres. In the ideal hyperbolic-hedgehog the molecular orientation is assumed to rotate proportionally with respect to the inclination angle, ? (and in the opposite sense). However, when splay, k11, and bend, k33, moduli differ this proportionality is lost and the liquid crystal deforms relative to the ideal with bend and splay. Although slight, these deformations are shown to significantly shift the transition if k11/k33 is small. By increasing the degree of confinement the twist transition can be inhibited, a characteristic both hyperbolic and radial hedgehogs have in common. The twist transition of a hyperbolic defect that accompanies a particle is found to be well predicted by the earlier stability analysis of a thick shell.

  12. Nuclear excitation by electronic transition (NEET).

    SciTech Connect

    Ahmad, I.; Dunford, R. W.; Esbensen, H.; Gemmell, D. S.; Kanter, E. P.; Kraessig, B.; Ruett, U.; Southworth, S. H.

    1999-04-28

    We present a report on recent measurements using the Advanced Photon Source at Argonne National Laboratory to explore the phenomenon of Nuclear Excitation by Electronic Transition (NEET) in the {sup 189}Os atomic/nuclear system.

  13. Transition metal fluorides: from superconductors to multiferroics. 

    E-print Network

    Drathen, Christina

    2013-06-29

    Transition metal fluorides represent an important family of complex solids displaying a variety of different properties and interesting phenomena. Despite their remarkable behaviour, these classes of materials have not ...

  14. Steps Toward a Successful Transition to

    E-print Network

    Kaye, Jason P.

    ........................................................................ 12 Cover crop selection and management .............................................. 12 STEP 3 STEP 4: Crop residue management........................................................... 15 STEP 5Steps Toward a Successful Transition to No-Till Sjoerd W. Duiker Soil Management Specialist, Penn

  15. "Explosive Percolation" Transition is Actually Continuous

    E-print Network

    R. A. da Costa; S. N. Dorogovtsev; A. V. Goltsev; J. F. F. Mendes

    2010-09-15

    The basic notion of percolation in physics assumes the emergence of a giant connected (percolation) cluster in a large disordered system when the density of connections exceeds some critical value. Until recently, the percolation phase transitions were believed to be continuous, however, in 2009, a remarkably different, discontinuous phase transition was reported in a new so-called "explosive percolation" problem. Each link in this problem is established by a specific optimization process. Here, employing strict analytical arguments and numerical calculations, we find that in fact the "explosive percolation" transition is continuous though with an uniquely small critical exponent of the percolation cluster size. These transitions provide a new class of critical phenomena in irreversible systems and processes.

  16. Seismic imaging of the mantle transition zone

    E-print Network

    Cao, Qin, Ph. D. Massachusetts Institute of Technology

    2012-01-01

    In this thesis, we developed a generalized Radon transform of SS precursors for large-scale, high-resolution seismo-stratigraphy of the upper mantle transition zone. The generalized Radon transform (GRT) is based on the ...

  17. 39 CFR 3010.29 - Transition rule.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... POSTAL REGULATORY COMMISSION PERSONNEL REGULATION OF RATES FOR MARKET DOMINANT PRODUCTS Rules for Applying the Price Cap § 3010.29 Transition rule. If the Postal Service initial exercise of its authority to file a Type 1-A notice...

  18. 39 CFR 3010.29 - Transition rule.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... POSTAL REGULATORY COMMISSION PERSONNEL REGULATION OF RATES FOR MARKET DOMINANT PRODUCTS Rules for Applying the Price Cap § 3010.29 Transition rule. If the Postal Service initial exercise of its authority to file a Type 1-A notice...

  19. 76 FR 77302 - Federal Transit Administration

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-12

    ...Administration FY 2011 Discretionary Sustainability Funding Opportunity; Transit Investments...Administration (FTA), DOT. ACTION: FTA Sustainability Program Funds: Announcement of Project...of Transportation's environmental sustainability efforts and were announced in...

  20. The Rarest Eclipse: Transit of Venus

    NSDL National Science Digital Library

    The transit of Venus across the disk of the sun is a rare astronomical event that has transfixed astronomers for centuries. June 8, 2004 marked the last occurrence of this event. Due to its extreme rarity (occurring only twice a century) this past transit has been heavily documented and researched by scientists across the globe. This site from the Exploratorium contains educational webcasts and RealMedia streaming coverage of the event. The last instance of the transit of Venus in 1882 is also well documented on this site with an interview from Tony Misch of Lick Observatory and a Quicktime animation made with glass plate negatives. The site provides background information about the planet Venus and the importance of its transit across the sun, as well as information on how to view the event. Educators's will find the "Teacher's Guide" especially useful for lesson and activity plans revolving around Venus.

  1. Transit Timing Variations - Duration: 81 seconds.

    NASA Video Gallery

    The animation shows the difference between planet transit timing of single and multiple planet system. In tightly packed planetary systems, the gravitational pull of the planets among themselves ca...

  2. Critical behaviours of contact near phase transitions

    PubMed Central

    Chen, Y.-Y.; Jiang, Y.-Z.; Guan, X.-W.; Zhou, Qi

    2014-01-01

    A central quantity of importance for ultracold atoms is contact, which measures two-body correlations at short distances in dilute systems. It appears in universal relations among thermodynamic quantities, such as large momentum tails, energy and dynamic structure factors, through the renowned Tan relations. However, a conceptual question remains open as to whether or not contact can signify phase transitions that are insensitive to short-range physics. Here we show that, near a continuous classical or quantum phase transition, contact exhibits a variety of critical behaviours, including scaling laws and critical exponents that are uniquely determined by the universality class of the phase transition, and a constant contact per particle. We also use a prototypical exactly solvable model to demonstrate these critical behaviours in one-dimensional strongly interacting fermions. Our work establishes an intrinsic connection between the universality of dilute many-body systems and universal critical phenomena near a phase transition. PMID:25346226

  3. Using Portfolios in Mid-Career Transitions.

    ERIC Educational Resources Information Center

    McDaniels, Carl

    2001-01-01

    The trend in career portfolio use is merging with the trend toward self-assessment. Portfolios can assist individuals in midlife transitions by enabling life review and redirection. (Contains 16 references.) (SK)

  4. SUCCESSFUL TRANSITION Counseling & Substance Abuse Services

    E-print Network

    Kasman, Alex

    SUCCESSFUL TRANSITION TO COLLEGE Counseling & Substance Abuse Services Director, Frank Budd, Ph Services · Office of Disability Services · Their Residence Assistant or the RHD · Counseling and Substance Abuse Services · Office of Undergraduate Admissions · Dean of Students There are MANY others!!! #12

  5. Continuum ionization transition probabilities of atomic oxygen

    NASA Technical Reports Server (NTRS)

    Samson, J. R.; Petrosky, V. E.

    1973-01-01

    The technique of photoelectron spectroscopy was used to obtain the relative continuum transition probabilities of atomic oxygen at 584 A for transitions from 3P ground state into the 4S, D2, and P2 states of the ion. Transition probability ratios for the D2 and P2 states relative to the S4 state of the ion are 1.57 + or - 0.14 and 0.82 + or - 0.07, respectively. In addition, transitions from excited O2(a 1 Delta g) state into the O2(+)(2 Phi u and 2 Delta g) were observed. The adiabatic ionization potential of O2(+)(2 Delta g) was measured as 18.803 + or - 0.006 eV.

  6. The Transition Between Rocky and Gaseous Planets

    NASA Astrophysics Data System (ADS)

    Rogers, Leslie

    2015-01-01

    The Kepler Mission, combined with ground based radial velocity follow-up and dynamical analyses of transit timing variations, has revolutionized the observational constraints on sub-Neptune-size planet compositions. In this talk, I focus on the intriguing transition between rocky exoplanets (comprised of iron and silicates) and planets with voluminous layers of volatiles (H/He and astrophysical ices). Applying a hierarchical Bayesian statistical approach to the sample of Kepler transiting sub-Neptune planets with Keck radial velocity follow-up, I constrain the fraction of close-in planets (with orbital periods less than 50 days) that are sufficiently dense to be rocky, as a function of planet radius, and find that the majority of close-in 1.6 Earth-radius planets are not rocky. I conclude by discussing future prospects for constraining the rocky-gaseous transition at longer orbital periods and for resolving compositional sub-populations in the accumulating census of observed exoplanets.

  7. 42 CFR 413.340 - Transition period.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...PROSPECTIVELY DETERMINED PAYMENT RATES FOR SKILLED NURSING FACILITIES Prospective Payment for Skilled Nursing Facilities § 413.340 Transition period...c) SNFs participating in the Multistate Nursing Home Case-Mix and Quality...

  8. 42 CFR 413.340 - Transition period.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...PROSPECTIVELY DETERMINED PAYMENT RATES FOR SKILLED NURSING FACILITIES Prospective Payment for Skilled Nursing Facilities § 413.340 Transition period...c) SNFs participating in the Multistate Nursing Home Case-Mix and Quality...

  9. 42 CFR 413.340 - Transition period.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...PROSPECTIVELY DETERMINED PAYMENT RATES FOR SKILLED NURSING FACILITIES Prospective Payment for Skilled Nursing Facilities § 413.340 Transition period...c) SNFs participating in the Multistate Nursing Home Case-Mix and Quality...

  10. 42 CFR 413.340 - Transition period.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...PROSPECTIVELY DETERMINED PAYMENT RATES FOR SKILLED NURSING FACILITIES Prospective Payment for Skilled Nursing Facilities § 413.340 Transition period...c) SNFs participating in the Multistate Nursing Home Case-Mix and Quality...

  11. 42 CFR 413.340 - Transition period.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...PROSPECTIVELY DETERMINED PAYMENT RATES FOR SKILLED NURSING FACILITIES Prospective Payment for Skilled Nursing Facilities § 413.340 Transition period...c) SNFs participating in the Multistate Nursing Home Case-Mix and Quality...

  12. 33 CFR 401.74 - Transit declaration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...the Seaway Transit Declaration Form. (d) A Weight-Scale Certificate or similar document issued in the place of...declaration form. (Approved by the Office of Management and Budget under control number 2135-0003) (68 Stat....

  13. 33 CFR 401.74 - Transit declaration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...the Seaway Transit Declaration Form. (d) A Weight-Scale Certificate or similar document issued in the place of...declaration form. (Approved by the Office of Management and Budget under control number 2135-0003) (68 Stat....

  14. The discontinuous volume change in transition-metal compounds due to the pressure-induced spin-state transition

    Microsoft Academic Search

    F. Ogata; T. Kambara; N. Sasaki; K. I. Gondaira

    1983-01-01

    Several transition-metal compounds change their volume abruptly under high pressure through their electronic spin-state transition. The pressure-induced spin-state transitions in transition-metal compounds are studied on the basis of the ligand-field theory by using the model in which the coupling of transition-metal ions with crystal distortions is taken into account. The various types of transitions occur due to the crystal distortion

  15. Wetting and layering transitions in magnetic films

    NASA Astrophysics Data System (ADS)

    Ez-Zahraouy, H.; Benyoussef, A.; Bahmad, L.

    2006-09-01

    The understanding of the surface effect on wetting and layering transitions was explained both theoretically and experimentally. Indeed, using different spin system models and different numerical and approximate methods such as mean field and effective field theories, real space renormalization technique and Monte-Carlo simulations, it is found that the wetting and layering transitions depend on the nature of the surface magnetic field, the surface coupling strength, the surface crystal field, the geometry of surface, the in-homogeneity of substrate and the quantum fluctuations at the surface. It is also found that the layering transition temperature increases or decreases as a function of the film thickness depending on the surface coupling values. The wetting transition temperature can be greater or smaller than the layering temperature. In the case of a variable surface crystal field, an order-disorder layering reentrance is found with new critical exponents behaviour. The wetting phenomena are also influenced by the nature of the surface. In fact the intra-layer transitions appear under the effect of an edge on the surface and/or corrugated surfaces. However, the intra-layering transitions are found for a surface temperature above, which the surface and the intra-layer surface occur. While the bulk layering and intra-layering transitions appear above another finite temperature which is greater than the former one. Such result is not found in the case of a perfect surface. Beside this, and under the corrugation effect, the pre-wetting phenomena and layering transitions occur at zero temperature, even in the case of a uniform magnetic field. In this case the wetting temperature depends strongly on the width of the corrugated-steps but weakly on its number.

  16. Heterotic Kahler/non-Kahler Transitions

    E-print Network

    Melanie Becker; Li-Sheng Tseng; Shing-Tung Yau

    2007-06-28

    We show how two topologically distinct spaces - the Kahler K3 x T^2 and the non-Kahler T^2 bundle over K3 - can be smoothly connected in heterotic string theory. The transition occurs when the base K3 is deformed to the T^4/Z_2 orbifold limit. The orbifold theory can be mapped via duality to M-theory on K3 x K3 where the transition corresponds to an exchange of the two K3's.

  17. Quantum Criticality in Transition-Metal Oxides

    Microsoft Academic Search

    N. Büttgen; H.-A. Krug von Nidda; W. Kraetschmer; A. Günther; S. Widmann; S. Riegg; A. Krimmel; A. Loidl

    2010-01-01

    We report on experiments of the bulk susceptibility ?(T), heat capacity C(T)\\/T, resistivity ?(T) and nuclear resonances (NMR and NQR) in order to review evidence of quantum critical behaviour in some metallic transition-metal\\u000a oxides. In analogy to the conventional 4f- and 5f-electron based heavy-fermion compounds, the prerequisites of quantum criticality, i.e. a magnetic phase transition at T=0 accompanied by non-Fermi

  18. Orbital Physics in Transition-Metal Oxides

    Microsoft Academic Search

    Y. Tokura; N. Nagaosa

    2000-01-01

    An electron in a solid, that is, bound to or nearly localized on the specific atomic site, has three attributes: charge, spin, and orbital. The orbital represents the shape of the electron cloud in solid. In transition-metal oxides with anisotropic-shaped d-orbital electrons, the Coulomb interaction between the electrons (strong electron correlation effect) is of importance for understanding their metal-insulator transitions

  19. Quantum phase transitions in rotating nuclei

    SciTech Connect

    Nazmitdinov, R. G. [Bogoliubov Laboratory of Theoretical Physics, JINR, 141980 Dubna (Russian Federation); Departament de Fisica, UIB, E-07122 Palma de Mallorca (Spain); Kvasil, J. [Institute of Particle and Nuclear Physics, Charles University, V. Holesovickach 2, CZ-18000 Praha 8 (Czech Republic)

    2009-01-28

    We extend the classical Landau theory for rotating nuclei and show that the backbending in {sup 162}Yb, that comes about as a result of the two-quasiparticle alignment, is identified with the second order phase transition. We found that the backbending in {sup 156}Dy, caused by the instability of {gamma}-vibrations in the rotating frame, corresponds to the first order phase transition.

  20. ?c ? ??c* transition in lattice QCD

    NASA Astrophysics Data System (ADS)

    Bahtiyar, H.; Can, K. U.; Erkol, G.; Oka, M.

    2015-07-01

    We study the electromagnetic ?c ? ??c* transition in 2 + 1 flavor lattice QCD, which gives access to the dominant decay mode of ?c* baryon. The magnetic dipole and the electric quadrupole transition form factors are computed. The magnetic dipole form factor is found to be mainly determined by the strange quark and the electric quadrupole form factor to be negligibly small, in consistency with the quark model. We also evaluate the helicity amplitudes and the decay rate.

  1. First Order Phase Transitions in Gravitational Collapse

    E-print Network

    P. Bizo?; T. Chmaj

    1998-01-31

    In recent numerical simulations of spherically symmetric gravitational collapse a new type of critical behaviour, dominated by a sphaleron solution, has been found. In contrast to the previously studied models, in this case there is a finite gap in the spectrum of black-hole masses which is reminiscent of a first order phase transition. We briefly summarize the essential features of this phase transition and describe the basic heuristic picture underlying the numerical phenomenology.

  2. Mass Transit Living Lab: Analyze the Data

    NSDL National Science Digital Library

    Civil and Environmental Engineering Department,

    Students go through the logical process of quantitatively analyzing real-world transit data. They gain experience identifying problems with the current design based upon their earlier observations and experiences in activities 1 and 2. Students discuss the flaws that they find in the system. This activity requires the use of the Mass Transit Living Lab—a web portal to interactive train traffic data for a major metropolitan city.

  3. The Casimir effect across a superconducting transition

    NASA Astrophysics Data System (ADS)

    Raines, Zachary; Allocca, Andrew; Galitski, Victor

    2014-03-01

    We show that Casimir effect can be used as a means to probe electronic correlations. In particular, we consider an interacting electron system which undergoes a superconducting transition and calculate the Casimir force it exerts on a normal metal. We found an interesting non-analytic behavior of the Casimir force as a function of temperature across the superconducting transition. This research is supported by DOE-BES (DESC0001911) and the Simons Foundation.

  4. Axion Dark Matter Detection using Atomic Transitions

    E-print Network

    P. Sikivie

    2014-09-09

    Dark matter axions may cause transitions between atomic states that differ in energy by an amount equal to the axion mass. Such energy differences are conveniently tuned using the Zeeman effect. It is proposed to search for dark matter axions by cooling a kilogram-sized sample to milliKelvin temperatures and count axion induced transitions using laser techniques. This appears an appropriate approach to axion dark matter detection in the $10^{-4}$ eV mass range.

  5. Axion dark matter detection using atomic transitions.

    PubMed

    Sikivie, P

    2014-11-14

    Dark matter axions may cause transitions between atomic states that differ in energy by an amount equal to the axion mass. Such energy differences are conveniently tuned using the Zeeman effect. It is proposed to search for dark matter axions by cooling a kilogram-sized sample to millikelvin temperatures and count axion induced transitions using laser techniques. This appears to be an appropriate approach to axion dark matter detection in the 10^{-4}??eV mass range. PMID:25432034

  6. The ?P transition form factors in QCD

    NASA Astrophysics Data System (ADS)

    Kroll, P.

    2012-04-01

    In an analysis by Kroll (2011) [11] the form factors for the transitions from a photon to a pseudoscalar meson P=?0,?,??,?c within QCD are reported. The sharp rise of the ?? form factor with the photon virtuality demands strong power corrections to the results from collinear factorization in contrast to the other transition form factors. The power corrections are modeled as quark transverse momenta accompanied by gluon radiation.

  7. Entropy in the quark-hadron transition

    E-print Network

    Kanako Yamazaki; T. Matsui; Gordon Baym

    2014-08-05

    We study, in the PNJL model, how the entropy of interacting quarks reflects the change in the effective degrees of freedom as the temperature increases through the quark-hadron phase transition. With inclusion of mesonic correlations, the effective degrees of freedom change from those of pi and sigma mesons at low temperatures to those of free quarks at high temperatures, with a resultant second order phase deconfinement transition in the chiral limit.

  8. Transcriptional Networks in Epithelial-Mesenchymal Transition

    Microsoft Academic Search

    Christo Venkov; David Plieth; Terri Ni; Amitava Karmaker; Aihua Bian; Alfred L. George; Eric G. Neilson; Joseph Najbauer

    2011-01-01

    BackroundEpithelial-mesenchymal transition (EMT) changes polarized epithelial cells into migratory phenotypes associated with loss of cell-cell adhesion molecules and cytoskeletal rearrangements. This form of plasticity is seen in mesodermal development, fibroblast formation, and cancer metastasis.Methods and FindingsHere we identify prominent transcriptional networks active during three time points of this transitional process, as epithelial cells become fibroblasts. DNA microarray in cultured epithelia

  9. Numerical simulations of hyperfine transitions of antihydrogen

    NASA Astrophysics Data System (ADS)

    Kolbinger, B.; Capon, A.; Diermaier, M.; Lehner, S.; Malbrunot, C.; Massiczek, O.; Sauerzopf, C.; Simon, M. C.; Widmann, E.

    2015-02-01

    One of the ASACUSA (Atomic Spectroscopy And Collisions Using Slow Antiprotons) collaboration's goals is the measurement of the ground state hyperfine transition frequency in antihydrogen, the antimatter counterpart of one of the best known systems in physics. This high precision experiment yields a sensitive test of the fundamental symmetry of CPT. Numerical simulations of hyperfine transitions of antihydrogen atoms have been performed providing information on the required antihydrogen events and the achievable precision.

  10. Dimensional phase transition in small Yukawa clusters

    SciTech Connect

    Sheridan, T. E.; Wells, K. D. [Department of Physics and Astronomy, Ohio Northern University, Ada, Ohio 45810 (United States)

    2010-01-15

    We investigate the one- to two-dimensional zigzag transition in clusters consisting of a small number of particles interacting through a Yukawa (Debye) potential and confined in a two-dimensional biharmonic potential well. Dusty (complex) plasma clusters with n<=19 monodisperse particles are characterized experimentally for two different confining wells. The well anisotropy is accurately measured, and the Debye shielding parameter is determined from the longitudinal breathing frequency. Debye shielding is shown to be important. A model for this system is used to predict equilibrium particle configurations. The experiment and model exhibit excellent agreement. The critical value of n for the zigzag transition is found to be less than that predicted for an unshielded Coulomb interaction. The zigzag transition is shown to behave as a continuous phase transition from a one-dimensional to a two-dimensional state, where the state variables are the number of particles, the well anisotropy and the Debye shielding parameter. A universal critical exponent for the zigzag transition is identified for transitions caused by varying the Debye shielding parameter.

  11. Late-time cosmological phase transitions

    SciTech Connect

    Schramm, D.N. (Chicago Univ., IL (USA) Fermi National Accelerator Lab., Batavia, IL (USA))

    1990-11-01

    It is shown that the potential galaxy formation and large-scale structure problems of objects existing at high redshifts (Z {approx gt} 5), structures existing on scales of 100M pc as well as velocity flows on such scales, and minimal microwave anisotropies ({Delta}T/T) {approx lt} 10{sup {minus}5} can be solved if the seeds needed to generate structure form in a vacuum phase transition after decoupling. It is argued that the basic physics of such a phase transition is no more exotic than that utilized in the more traditional GUT scale phase transitions, and that, just as in the GUT case, significant random gaussian fluctuations and/or topological defects can form. Scale lengths of {approximately}100M pc for large-scale structure as well as {approximately}1 M pc for galaxy formation occur naturally. Possible support for new physics that might be associated with such a late-time transition comes from the preliminary results of the SAGE solar neutrino experiment, implying neutrino flavor mixing with values similar to those required for a late-time transition. It is also noted that a see-saw model for the neutrino masses might also imply a tau neutrino mass that is an ideal hot dark matter candidate. However, in general either hot or cold dark matter can be consistent with a late-time transition. 47 refs., 2 figs.

  12. Serpin latency transition at atomic resolution

    PubMed Central

    Cazzolli, Giorgia; Wang, Fang; a Beccara, Silvio; Gershenson, Anne; Faccioli, Pietro; Wintrode, Patrick L.

    2014-01-01

    Protease inhibition by serpins requires a large conformational transition from an active, metastable state to an inactive, stable state. Similar reactions can also occur in the absence of proteases, and these latency transitions take hours, making their time scales many orders of magnitude larger than are currently accessible using conventional molecular dynamics simulations. Using a variational path sampling algorithm, we simulated the entire serpin active-to-latent transition in all-atom detail with a physically realistic force field using a standard computing cluster. These simulations provide a unifying picture explaining existing experimental data for the latency transition of the serpin plasminogen activator inhibitor-1 (PAI-1). They predict a long-lived intermediate that resembles a previously proposed, partially loop-inserted, prelatent state; correctly predict the effects of PAI-1 mutations on the kinetics; and provide a potential means to identify ligands able to accelerate the latency transition. Interestingly, although all of the simulated PAI-1 variants readily access the prelatent intermediate, this conformation is not populated in the active-to-latent transition of another serpin, ?1-antitrypsin, which does not readily go latent. Thus, these simulations also help elucidate why some inhibitory serpin families are more conformationally labile than others. PMID:25313058

  13. The ?–? phase transition in volcanic cristobalite

    PubMed Central

    Damby, David E.; Llewellin, Edward W.; Horwell, Claire J.; Williamson, Ben J.; Najorka, Jens; Cressey, Gordon; Carpenter, Michael

    2014-01-01

    Cristobalite is a common mineral in volcanic ash produced from dome-forming eruptions. Assessment of the respiratory hazard posed by volcanic ash requires understanding the nature of the cristobalite it contains. Volcanic cristobalite contains coupled substitutions of Al3+ and Na+ for Si4+; similar co-substitutions in synthetic cristobalite are known to modify the crystal structure, affecting the stability of the ? and ? forms and the observed transition between them. Here, for the first time, the dynamics and energy changes associated with the ?–? phase transition in volcanic cristobalite are investigated using X-ray powder diffraction with simultaneous in situ heating and differential scanning calorimetry. At ambient temperature, volcanic cristobalite exists in the ? form and has a larger cell volume than synthetic ?-cristobalite; as a result, its diffraction pattern sits between ICDD ?- and ?-cristobalite library patterns, which could cause ambiguity in phase identification. On heating from ambient temperature, volcanic cristobalite exhibits a lower degree of thermal expansion than synthetic cristobalite, and it also has a lower ?–? transition temperature (?473?K) compared with synthetic cristobalite (upwards of 543?K); these observations are discussed in relation to the presence of Al3+ and Na+ defects. The transition shows a stable and reproducible hysteresis loop with ? and ? phases coexisting through the transition, suggesting that discrete crystals in the sample have different transition temperatures. PMID:25242910

  14. Explosive synchronization transitions in complex neural network

    E-print Network

    Hanshuang Chen; Feng Huang; Chuansheng Shen; Zhonghuai Hou

    2013-03-15

    It has been recently reported that explosive synchronization transitions can take place in networks of phase oscillators [G\\'omez-Garde\\~nes \\emph{et al.} Phys.Rev.Letts. 106, 128701 (2011)] and chaotic oscillators [Leyva \\emph{et al.} Phys.Rev.Letts. 108, 168702 (2012)]. Here, we investigate the effect of a microscopic correlation between the dynamics and the interacting topology of coupled FitzHugh-Nagumo oscillators on phase synchronization transition in Barab\\'asi-Albert (BA) scale-free networks and Erd\\"os-R\\'enyi (ER) random networks. We show that, if the width of distribution of natural frequencies of the oscillations is larger than a threshold value, a strong hysteresis loop arises in the synchronization diagram of BA networks due to the positive correlation between node degrees and natural frequencies of the oscillations, indicating the evidence of an explosive transition towards synchronization of relaxation oscillators system. In contrast to the results in BA networks, in more homogeneous ER networks the synchronization transition is always of continuous type regardless of the the width of the frequency distribution. Moreover, we consider the effect of degree-mixing patterns on the nature of the synchronization transition, and find that the degree assortativity is unfavorable for the occurrence of such an explosive transition.

  15. Atomic Transition Probabilities Scandium through Manganese

    SciTech Connect

    Martin, G.A.; Fuhr, J.R.; Wiese, W.L.

    1988-10-01

    Atomic transition probabilities for about 8,800 spectral lines of five iron-group elements, Sc(Z = 21) to Mn(Z = 25), are critically compiled, based on all available literature sources. The data are presented in separate tables for each element and stage of ionization and are further subdivided into allowed (i.e., electric dipole-E1) and forbidden (magnetic dipole-M1, electric quadrupole-E2, and magnetic quadrupole-M2) transitions. Within each data table the spectral lines are grouped into multiplets, which are in turn arranged according to parent configurations, transition arrays, and ascending quantum numbers. For each line the transition probability for spontaneous emission and the line strength are given, along with the spectroscopic designation, the wavelength, the statistical weights, and the energy levels of the upper and lower states. For allowed lines the absorption oscillator strength is listed, while for forbidden transitions the type of transition is identified (M1, E2, etc.). In addition, the estimated accuracy and the source are indicated. In short introductions, which precede the tables for each ion, the main justifications for the choice of the adopted data and for the accuracy rating are discussed. A general introduction contains a discussion of our method of evaluation and the principal criteria for our judgements.

  16. Outlook on a Worldwide Forest Transition

    PubMed Central

    Pagnutti, Chris; Bauch, Chris T.; Anand, Madhur

    2013-01-01

    It is not clear whether a worldwide “forest transition” to net reforestation will ever occur, and the need to address the main driver–agriculture–is compelling. We present a mathematical model of land use dynamics based on the world food equation that explains historical trends in global land use on the millennial scale. The model predicts that a global forest transition only occurs under a small and very specific range of parameter values (and hence seems unlikely) but if it does occur, it would have to occur within the next 70 years. In our baseline scenario, global forest cover continues to decline until it stabilizes within the next two centuries at 22% of global land cover, and wild pasture at 1.4%. Under other scenarios the model predicts unanticipated dynamics wherein a forest transition may relapse, heralding a second era of deforestation; this brings into question national-level forest transitions observed in recent decades, and suggests we need to expand our lexicon of possibilities beyond the simple “forest transition/no forest transition” dichotomy. This research also underscores that the challenge of feeding a growing population while conserving natural habitat will likely continue for decades to come. PMID:24130750

  17. Transition of management in adolescents with IBD.

    PubMed

    Zeisler, Bella; Hyams, Jeffrey S

    2014-02-01

    Transfer of care is when a patient and his or her medical records move from one provider to another at a distinct point in time. By contrast, transition of care is a gradual process of change in knowledge, attitudes and behaviour through which the adolescent can learn to assume personal responsibility for his or her health care. IBD is a prevalent disorder, often diagnosed during childhood. Because mortality of this condition is fortunately low, children diagnosed with IBD will, at some point, transition from a paediatric to adult health-care model. Paediatric and adult health-care paradigms, including IBD-specific care, are different in a number of key areas and it is becoming increasingly apparent that young adults with chronic illness often face challenging transitions, resulting in compromised physical and emotional health outcomes. In the past decade, refining the processes related to transition of care for adolescents with chronic medical conditions has gained traction as an important public health initiative. The aim of this paper is to review concepts pertinent to transition of management for adolescents and young adults with IBD, and to review the current literature and evidence supporting transitional care in paediatric IBD. PMID:24419396

  18. Transits of Earth-like Planets

    NASA Astrophysics Data System (ADS)

    Kaltenegger, Lisa; Traub, Wesley A.

    2009-06-01

    Transmission spectroscopy of Earth-like exoplanets is a potential tool for habitability screening. Transiting planets are present-day "Rosetta Stones" for understanding extrasolar planets because they offer the possibility to characterize giant planet atmospheres and should provide an access to biomarkers in the atmospheres of Earth-like exoplanets, once they are detected. Using the Earth itself as a proxy we show the potential and limits of the transiting technique to detect biomarkers on an Earth-analog exoplanet in transit. We quantify the Earth's cross section as a function of wavelength, and show the effect of each atmospheric species, aerosol, and Rayleigh scattering. Clouds do not significantly affect this picture because the opacity of the lower atmosphere from aerosol and Rayleigh losses dominates over cloud losses. We calculate the optimum signal-to-noise ratio for spectral features in the primary eclipse spectrum of an Earth-like exoplanet around a Sun-like star and also M stars, for a 6.5 m telescope in space. We find that the signal-to-noise values for all important spectral features are on the order of unity or less per transit—except for the closest stars—making it difficult to detect such features in one single transit, and implying that coadding of many transits will be essential.

  19. Using Transit Timing Observations to Search for Trojans of Transiting Extrasolar Planets

    E-print Network

    Eric B. Ford; Matthew J. Holman

    2007-05-03

    Theoretical studies predict that Trojans are likely a frequent byproduct of planet formation and evolution. We examine the sensitivity of transit timing observations for detecting Trojan companions to transiting extrasolar planets. We demonstrate that this method offers the potential to detect terrestrial-mass Trojans using existing ground-based observatories. We compare the transit timing variation (TTV) method with other techniques for detecting extrasolar Trojans and outline the future prospects for this method.

  20. Using Transit Timing Observations to Search for Trojans of Transiting Extrasolar Planets

    Microsoft Academic Search

    Eric B. Ford; Matthew J. Holman

    2007-01-01

    Theoretical studies predict that Trojans are likely a frequent byproduct of\\u000aplanet formation and evolution. We examine the sensitivity of transit timing\\u000aobservations for detecting Trojan companions to transiting extrasolar planets.\\u000aWe demonstrate that this method offers the potential to detect terrestrial-mass\\u000aTrojans using existing ground-based observatories. We compare the transit\\u000atiming variation (TTV) method with other techniques for detecting

  1. New ferroelastic phase transition induced by impurity tunneling with a structural local transition

    NASA Astrophysics Data System (ADS)

    Vikhnin, V. S.; Maksimova, T. I.

    2009-12-01

    We predict a new ferroelastic phase transition in a matrix, which is induced by the tunneling states appearing under the conditions of structural local transitions for impurity ions. This ferroelastic phase transition has been studied in crystals of the proper ferroelastic K3Na(CrO4)2 with impurity molecular ions of MnO{4/2-} and the dielectric KCl with impurity atoms of Cu0. A model of the induced phase transitions of this type is proposed and the related applications are discussed.

  2. Polarization in Exoplanetary Systems Caused by Transits, Grazing Transits, and Starspots

    NASA Astrophysics Data System (ADS)

    Kostogryz, N. M.; Yakobchuk, T. M.; Berdyugina, S. V.

    2015-06-01

    We present results of numerical simulations of flux and linear polarization variations in transiting exoplanetary systems, caused by host star disk symmetry breaking. We consider different configurations of planetary transits depending on orbital parameters. The starspot contribution to the polarized signal is also estimated. Applying the method to known systems and simulating observational conditions, a number of targets is selected where transit polarization effects could be detected. We investigate several principal benefits of the transit polarimetry, particularly for determining orbital spatial orientation and distinguishing between grazing and near-grazing planets. Simulations show that polarization parameters are also sensitive to starspots, and they can be used to determine spot positions and sizes.

  3. An Observational Perspective of Transitional Disks

    NASA Astrophysics Data System (ADS)

    Espaillat, C.; Muzerolle, J.; Najita, J.; Andrews, S.; Zhu, Z.; Calvet, N.; Kraus, S.; Hashimoto, J.; Kraus, A.; D'Alessio, P.

    Transitional disks are objects whose inner disk regions have undergone substantial clearing. The Spitzer Space Telescope produced detailed spectral energy distributions (SEDs) of transitional disks that allowed us to infer their radial dust disk structure in some detail, revealing the diversity of this class of disks. The growing sample of transitional disks also opened up the possibility of demographic studies, which provided unique insights. There now exist (sub)millimeter and infrared images that confirm the presence of large clearings of dust in transitional disks. In addition, protoplanet candidates have been detected within some of these clearings. Transitional disks are thought to be a strong link to planet formation around young stars and are a key area to study if further progress is to be made on understanding the initial stages of planet formation. Here we provide a review and synthesis of transitional disk observations to date with the aim of providing timely direction to the field, which is about to undergo its next burst of growth as the Atacama Large Millimeter/submillimeter Array (ALMA) reaches its full potential. We discuss what we have learned about transitional disks from SEDs, color-color diagrams, and imaging in the (sub)millimeter and infrared. We note the limitations of these techniques, particularly with respect to the sizes of the clearings currently detectable, and highlight the need for pairing broadband SEDs with multi-wavelength images to paint a more detailed picture of transitional disk structure. We review the gas in transitional disks, keeping in mind that future observations with ALMA will give us unprecedented access to gas in disks, and also observed infrared variability pointing to variable transitional disk structure, which may have implications for disks in general. We then distill the observations into constraints for the main disk-clearing mechanisms proposed to date (i.e., photoevaporation, grain growth, and companions) and explore how the expected observational signatures from these mechanisms, particularly planet-induced disk clearing, compare to actual observations. Finally, we discuss future avenues of inquiry to be pursued with ALMA, the James Webb Space Telescope (JWST), and the next generation of groundbased telescopes.

  4. Transitions of tethered chain molecules under tension

    E-print Network

    Jutta Luettmer-Strathmann; Kurt Binder

    2014-09-09

    An applied tension force changes the equilibrium conformations of a polymer chain tethered to a planar substrate and thus affects the adsorption transition as well as the coil-globule and crystallization transitions. Conversely, solvent quality and surface attraction are reflected in equilibrium force-extension curves that can be measured in experiments. To investigate these effects theoretically, we study tethered chains under tension with Wang-Landau simulations of a bond-fluctuation lattice model. Applying our model to pulling experiments on biological molecules we obtain a good description of experimental data in the intermediate force range, where universal features dominate and finite size effects are small. For tethered chains in poor solvent, we observe the predicted two-phase coexistence at transitions from the globule to stretched conformations and also discover direct transitions from crystalline to stretched conformations. A phase portrait for finite chains constructed by evaluating the density of states for a broad range of solvent conditions and tensions shows how increasing tension leads to a disappearance of the globular phase. For chains in good solvents tethered to hard and attractive surfaces we find the predicted scaling with the chain length in the low-force regime and show that our results are well described by an analytical, independent-bond approximation for the bond-fluctuation model for the highest tensions. Finally, for a hard or slightly attractive surface the stretching of a tethered chain is a conformational change that does not correspond to a phase transition. However, when the surface attraction is sufficient to adsorb a chain it will undergo a desorption transition at a critical value of the applied force. Our results for force-induced desorption show the transition to be discontinuous with partially desorbed conformations in the coexistence region.

  5. Microwave-assisted synthesis of transition metal phosphide

    DOEpatents

    Viswanathan, Tito

    2014-12-30

    A method of synthesizing transition metal phosphide. In one embodiment, the method has the steps of preparing a transition metal lignosulfonate, mixing the transition metal lignosulfonate with phosphoric acid to form a mixture, and subjecting the mixture to a microwave radiation for a duration of time effective to obtain a transition metal phosphide.

  6. Timing Detection of Eclipsing Binary Planets and Transiting Extrasolar Moons

    E-print Network

    Deeg, Hans-Jörg

    Timing Detection of Eclipsing Binary Planets and Transiting Extrasolar Moons Laurance R. Doyle SETI eclipsing binaries using eclipse minima timing and extrasolar moons around transiting planets using transit around transiting planets will be accomplished by these missions. Eclipsing Binary Minima Timing

  7. Impacts of Transit Oriented Development on Public Transportation Ridership

    Microsoft Academic Search

    Sara J Hendricks

    2005-01-01

    The purpose of Phase I of this study was to develop a research design to better establish the relationship between transit oriented development (TOD) and travel mode share. The initial hypothesis that good quality transit combined with good quality TOD would succeed in shifting travelers from single-occupant vehicle travel to transit was found to be an oversimplification. Good quality transit

  8. Initial infrastructure development strategies for the transition to sustainable mobility

    Microsoft Academic Search

    Floris J. Huétink; Alexander van der Vooren; Floortje Alkemade

    2010-01-01

    Within the Dutch transition policy framework, the transition to hydrogen-based transport is seen as a promising option towards a sustainable transport system. One aspect of such transition processes that is emphasized in transition management is learning about user behaviour and preferences. However, while earlier research on sustainable mobility acknowledges the importance of refuelling infrastructure, the question of how to unroll

  9. Accelerating the flow: A transition effect in programming theory?

    Microsoft Academic Search

    Susan Tyler Eastman; Gregory D. Newton; Karen E. Riggs

    1997-01-01

    Examination of 240 transitions between prime?time programs on the four broadcast networks demonstrated the existence of a modest transition effect and revealed differences in transitions over time, suggesting that a transition effect associates with the new fall network schedules but not with familiar spring schedules. It showed that program endings had a significant impact on duplicated viewers in subsequent programs

  10. Chemical reaction models for non-equilibrium phase transitions

    Microsoft Academic Search

    F. Schlögl

    1972-01-01

    Chemical model reactions are discussed the steady states of which show the phenomenon of non equilibrium phase transitions. One example shows a phase transition of second order, another one shows a phase transition of first order. If diffusion occurs in the case of first order transition, coexistence of two phases in different domains is possible. For plane boundary layers between

  11. Impedance Scaling for Small Angle Transitions

    SciTech Connect

    Stupakov, G.; Bane, Karl; /SLAC; Zagorodnov, I.; /DESY; ,

    2010-10-27

    Based on the parabolic equation approach to Maxwell's equations we have derived scaling properties of the high frequency impedance/short bunch wakefields of structures. For the special case of small angle transitions we have shown the scaling properties are valid for all frequencies. Using these scaling properties one can greatly reduce the calculation time of the wakefield/impedance of long, small angle, beam pipe transitions, like one often finds in insertion regions of storage rings. We have tested the scaling with wakefield simulations of 2D and 3D models of such transitions, and found that the scaling works well. In modern ring-based light sources one often finds insertion devices having extremely small vertical apertures (on the order of millimeters) to allow for maximal undulator fields reaching the beam. Such insertion devices require that there be beam pipe transitions from these small apertures to the larger cross-sections (normally on the order of centimeters) found in the rest of the ring. The fact that there may be many such transitions, and that these transitions introduce beam pipe discontinuities very close to the beam path, means that their impedance will be large and, in fact, may dominate the impedance budget of the entire ring. To reduce their impact on impedance, the transitions are normally tapered gradually over a long distance. The accurate calculation of the impedance or wakefield of these long transitions, which are typically 3D objects (i.e. they do not have cylindrical symmetry), can be quite a challenging numerical task. In this report we present a method of obtaining the impedance of a long, small angle transition from the calculation of a scaled, shorter one. Normally, the actual calculation is obtained from a time domain simulation of the wakefield in the structure, where the impedance can be obtained by performing a Fourier transform. We shall see that the scaled calculation reduces the computer time and memory requirements significantly, especially for 3D problems, and can make the difference between being able to solve a problem or not. The method is based on the parabolic equation approach to solving Maxwell's equation developed in Refs. [1, 2].

  12. Rethinking Healthcare Transitions and Policies: Changing and Expanding Roles in Transitional Care

    ERIC Educational Resources Information Center

    Moreño, Patricienn K.

    2014-01-01

    The breakdown of care transitions between various healthcare facilities, providers, and services is a major issue in healthcare, and accounts for over US$15 billion in healthcare expenditures annually. The transition between inpatient care and home care is a very delicate period where, too often, chronically ill patients get worse and wind up back…

  13. GILL TRANSIT CIRCLE (1901) The purpose of a transit circle was to provide extremely

    E-print Network

    Glass, Ian S.

    1901-01-01

    GILL TRANSIT CIRCLE (1901) The purpose of a transit circle was to provide extremely accurate of the telescope and read its position scales through numerous microscopes . The Gill-designed 6-inch Reversible in 1950 and 1960, for example by introducing automatic photography of the scales. Gill's design had

  14. Evidence-Based Instructional Strategies for Transition. Brookes Transition to Adulthood Series

    ERIC Educational Resources Information Center

    Test, David W.

    2012-01-01

    To meet the high-stakes requirements of IDEA's Indicator 13, professionals need proven and practical ways to support successful transitions for young adults with significant disabilities. Now there's a single guidebook to help them meet that critical goal--straight from David Test, one of today's most highly respected authorities on transitions to…

  15. Transitions from Temporary to Permanent Work in Canada: Who Makes the Transition and Why?

    ERIC Educational Resources Information Center

    Fang, Tony; MacPhail, Fiona

    2008-01-01

    The focus of this paper is on a microeconomic analysis of the annual transition rate from temporary to permanent work of individual workers in Canada for the period 1999-2004. Given that a large proportion of temporary employment is involuntary, an understanding of the factors associated with the transition to permanent work may inform public…

  16. Flight and wind-tunnel correlation of boundary-layer transition on the AEDC transition cone

    Microsoft Academic Search

    D. L. Fisher; N. S. Dougherty Jr.

    1982-01-01

    Transition and fluctuating surface pressure data were acquired on a 10 deg included angle cone, using the same instrumentation and technique over a wide range of Mach and Reynolds numbers in 23 wind tunnels and in flight. Transition was detected with a traversing pitot-pressure probe in contact with the surface. The surface pressure fluctuations were measured with microphones set flush

  17. Transition Planning for Culturally and Linguistically Diverse Youth. Brookes Transition to Adulthood Series

    ERIC Educational Resources Information Center

    Greene, Gary

    2011-01-01

    Too often, culturally and linguistically diverse (CLD) youth with disabilities have a tougher road to adulthood than their Caucasian peers with disabilities. Reverse the odds with this concise how-to book, the first guide to easing the complex transition process for CLD students with a wide range of special needs. A veteran trainer of transition

  18. Supporting the Child in Transition Packet. Bridging Early Services Transition Project.

    ERIC Educational Resources Information Center

    Rosenkoetter, Sharon; Shotts, Cynthia

    This packet provides a variety of information pieces to help early childhood educational programs prepare young children with disabilities for transition out of one program and into another. The booklet opens with sample thoughts children may have when anticipating transition. Next, 20 possible differences among programs are specifically…

  19. Family Partnership in Transition Planning Packet. Bridging Early Services Transition Project.

    ERIC Educational Resources Information Center

    Rosenkoetter, Sharon; Shotts, Cynthia

    This packet of handouts focuses on the role of the family in easing their child with disabilities from one early childhood educational program to another. Typical items include: reasons for involving families in transition; questions parents ask about "appropriate" placement; planned conversations with parents during the transition process; parent…

  20. Transition Planning Guide for Parents of Special Education Students. DISD Community Transition Model.

    ERIC Educational Resources Information Center

    Quinones, Bill; Ozmun, Ellie

    This transition planning guide is intended as a resource for parents of severely handicapped students approaching or at the legal age for leaving public school services and entering community services. The guide was developed after a 2-year transition project, Project Impact, revealed common concerns and questions which parents and teachers…