Science.gov

Sample records for retsensent matti piirsalu

  1. Mathilda (Matty) Bushel Canter (1924-2015).

    PubMed

    Matthews, Janet R

    2015-09-01

    Mathilda (Matty) Bushel Canter, a lifelong contributor to professional psychology, with a remarkable history of service, died in Phoenix, Arizona, on January 30, 2015. Matty was born in Brooklyn, New York, on June 8, 1924, the daughter of Harry and Bertha Bushel. She was preceded in death by her husband and fellow psychologist, Aaron Herman Canter in 1995. She and Aaron had two children, Rachelle (Shelley) and Steven. She is also survived by her brother Arthur Bushel of Baltimore. She made significant contributions to the profession on both a state and national level. Her contributions to the profession led to her being named a fellow of seven divisions of the American Psychological Association (APA; Divisions 12, 29, 31, 35, 42, 44, and 55). In 1984, she became the first female president of the APA Division of Psychotherapy (Division 29). In addition, she produced many articles for the media on the role of psychology in the community. Matty was a strong supporter of the American Psychological Foundation (APF). Matty received numerous awards from APA and its divisions for her contributions. She was a strong supporter of advocacy efforts in psychology and participated in numerous advocacy fundraising events. Her gentle way of handling tough situations earned nothing but respect. Matty mentored so many students and professionals, they are too numerous to note. A true giant of our profession has departed. PMID:26348338

  2. Lieb-Mattis ferrimagnetism in magnetic semiconductors

    NASA Astrophysics Data System (ADS)

    Kuzian, R. O.; Richter, J.; Kuz'min, M. D.; Hayn, R.

    2016-06-01

    We show the possibility of long-range ferrimagnetic ordering with a saturation magnetization of ˜1 μB per spin for arbitrarily low concentration of magnetic impurities in semiconductors, provided that the impurities form a superstructure satisfying the conditions of the Lieb-Mattis theorem. Explicit examples of such superstructures are given for the wurtzite lattice, and the temperature of ferrimagnetic transition is estimated from a high-temperature expansion. Exact diagonalization studies show that small fragments of the structure exhibit enhanced magnetic response and isotropic superparamagnetism at low temperatures. A quantum transition in a high magnetic field is considered and similar superstructures in cubic semiconductors are discussed as well.

  3. Narratives in Teaching Practice: Matti Raekallio as Narrator in His Piano Lessons

    ERIC Educational Resources Information Center

    Hyry-Beihammer, Eeva Kaisa

    2011-01-01

    The present article considers the narratives told in piano lessons, studied as both a teacher's "way of knowing" and as echoes of "masters' voices" in classical music. The main character is a well known Finnish music pedagogue and artist, Matti Raekallio, and the study focuses on his knowledge of teaching practice; that is, his practical…

  4. Long-term outcome of scaphoid nonunion treated by the Matti-Russe operation.

    PubMed

    Kołodziej, Robert Kołodziej; Blacha, Jan; Bogacz, Alina; Mazurkiewicz, Tomasz

    2006-10-31

    Background. This article presents the results of scaphoid non-union treatment using the Matti-Russe operation. The long-term outcome was compared in patients with bone union and patients with persistent nonunion. Materials and methods. We analyzed 81 cases (80 men, 1 woman) retrospectively. The end point was bone union or persistence of non-union. A long-term follow-up examination was done in 21 patients, with a follow-up ranging from 2 to 27 years (mean 8.8 years). Grip strength was measured with a dynamometer, range of movement was assessed, and the PRWE and DASH scales were used. Radiograms were evaluated for bone union, presence of osteoarthritis and radiolunate angle. Results. Bone union was achieved in 53 patients, persistent nonunion was observed in 23 patients (5 patients presented inadequate data for valid analysis). The long-term outcome was analyzed in 21 patients (14 with bone union and 7 with persistent nonunion). Better results based on subjective patient-rated scales were noticed in the group of bone union (PRWE 14.8, DASH 43.1) than in the non-union group (PRWE 30, DASH 61.8). Grip strength and range of movement were similar. The mean radiolunate angle was 9.6 in the bone union group, and 17.9 in the non-union group. Conclusions. The non-union ratio after Matti-Russe surgery was 28%. Grip strength and range of movement were similar in both groups. The results of the PRWE and DASH scales suggest better clinical outcome in patients with bone union.

  5. Screening for DSM-IV-TR Cognitive Disorder NOS in Parkinson’s disease using the Mattis Dementia Rating Scale

    PubMed Central

    Pontone, Gregory M.; Palanci, Justin; Williams, James R.; Bassett, Susan Spear

    2012-01-01

    Objective This study explores the utility of the Mattis Dementia Rating Scale (MDRS) as a screening tool for the Diagnostic and Statistical Manual for Mental Disorders 4th edition (DSM-IV-TR) diagnosis Cognitive Disorder Not Otherwise Specified in Parkinson’s disease(PD). Methods 125 individuals with PD were diagnosed using DSM-IV-TR criteria for Cognitive Disorder NOS and dementia. Receiver operating characteristics tested the discriminant validity of the MDRS, with the clinician’s diagnosis serving as the gold standard. Results The MDRS ROC curve to discriminate subjects with Cognitive Disorder NOS from non-demented subjects had an AUC of 0.59 (std. err.= 0.08, 95% CI: 0.43–0.74). Conclusions The MDRS is not effective for identifying PD patients with Cognitive Disorder NOS without dementia. PMID:22628158

  6. Removal of graffiti paintings from the Mansion de Mattis site in Corato (Bari), Italy: Laser deveiling or complete cleaning?

    NASA Astrophysics Data System (ADS)

    Daurelio, G.; Andriani, E. S.; Albanese, A.; Catalano, I. M.; Teseo, G.; Marano, D.

    2008-10-01

    Nowadays one the main problem of stone monuments conservation is not only the natural environment deterioration but the defaced, in particular esthetic, due to graffiti. This paper presents the different stages of the cleaning graffiti research: the laboratory study phase, in which the aims were to investigate the laser cleaning effect on substrate and testing user-friendly and efficient solutions for in situ application; the application phase in which the study results were applied in the restoration of Palazzo de Mattis facade. The graffiti cleaning were carried out by using a Q-Switch Nd:YAG laser source (λ=1064 nm with pulse duration, t=8 ns, f=2 to 20 Hz, energy per impulse up to 280 mJ) in dry, wet and Very wet modes adopting the Daurelio technique n.1 (blade spot laser). The Q-Switch Nd:Yag laser source has demonstrated to be the most suitable for a fully or, according to new restoring theory, "de veiling" graffiti ablation.

  7. High efficiency transformation of banana [Musa acuminata L. cv. Matti (AA)] for enhanced tolerance to salt and drought stress through overexpression of a peanut salinity-induced pathogenesis-related class 10 protein.

    PubMed

    Rustagi, Anjana; Jain, Shalu; Kumar, Deepak; Shekhar, Shashi; Jain, Mukesh; Bhat, Vishnu; Sarin, Neera Bhalla

    2015-01-01

    Bananas and plantains (Musa spp. L.) are important subsistence crops and premium export commodity in several countries, and susceptible to a wide range of environmental and biotic stress conditions. Here, we report efficient, rapid, and reproducible Agrobacterium-mediated transformation and regeneration of an Indian niche cultivar of banana [M. acuminata cv. Matti (AA)]. Apical meristem-derived highly proliferative multiple shoot clump (MSC) explants were transformed with the Agrobacterium strain EHA105 harboring a binary vector pCAMBIA-1301 carrying hptII and uidA. Sequential agro-infiltration (10 min, 400 mmHg), infection (additional 35 min, Agrobacterium density A 600 = 0.8) and co-cultivation (18 h) regimen in 100 µM acetosyringone containing liquid medium were critical factors yielding high transformation efficiency (~81 %) corroborated by transient GUS expression assay. Stable transgenic events were recovered following two cycles of meristem initiation and selection on hygromycin containing medium. Histochemical GUS assay in several tissues of transgenic plants and molecular analyses confirmed stable integration and expression of transgene. The protocol described here allowed recovery of well-established putative transgenic plantlets in as little as 5 months. The transgenic banana plants could be readily acclimatized under greenhouse conditions, and were phenotypically similar to the wild-type untransformed control plants (WT). Transgenic plants overexpressing Salinity-Induced Pathogenesis-Related class 10 protein gene from Arachis hypogaea (AhSIPR10) in banana cv. Matti (AA) showed better photosynthetic efficiency and less membrane damage (P < 0.05) in the presence of NaCl and mannitol in comparison to WT plants suggesting the role of AhSIPR10 in better tolerance of salt stress and drought conditions.

  8. A resolution honoring the extraordinary and courageous life of Mattie Stepanek.

    THOMAS, 113th Congress

    Sen. Mikulski, Barbara A. [D-MD

    2014-07-21

    07/21/2014 Submitted in the Senate, considered, and agreed to without amendment and with a preamble by Unanimous Consent. (consideration: CR S4664; text as passed Senate: CR S4663) (All Actions) Tracker: This bill has the status Passed SenateHere are the steps for Status of Legislation:

  9. First Calderón Prize

    NASA Astrophysics Data System (ADS)

    Rundell, William; Somersalo, Erkki

    2008-07-01

    The Inverse Problems International Association (IPIA) awarded the first Calderón Prize to Matti Lassas for his outstanding contributions to the field of inverse problems, especially in geometric inverse problems. The Calderón Prize is given to a researcher under the age of 40 who has made distinguished contributions to the field of inverse problems broadly defined. The first Calderón Prize Committee consisted of Professors Adrian Nachman, Lassi Päivärinta, William Rundell (chair), and Michael Vogelius. William Rundell For the Calderón Prize Committee Prize ceremony The ceremony awarding the Calderón Prize. Matti Lassas is on the left. He and William Rundell are on the right. Photos by P Stefanov. Brief Biography of Matti Lassas Matti Lassas was born in 1969 in Helsinki, Finland, and studied at the University of Helsinki. He finished his Master's studies in 1992 in three years and earned his PhD in 1996. His PhD thesis, written under the supervision of Professor Erkki Somersalo was entitled `Non-selfadjoint inverse spectral problems and their applications to random bodies'. Already in his thesis, Matti demonstrated a remarkable command of different fields of mathematics, bringing together the spectral theory of operators, geometry of Riemannian surfaces, Maxwell's equations and stochastic analysis. He has continued to develop all of these branches in the framework of inverse problems, the most remarkable results perhaps being in the field of differential geometry and inverse problems. Matti has always been a very generous researcher, sharing his ideas with his numerous collaborators. He has authored over sixty scientific articles, among which a monograph on inverse boundary spectral problems with Alexander Kachalov and Yaroslav Kurylev and over forty articles in peer reviewed journals of the highest standards. To get an idea of the wide range of Matti's interests, it is enough to say that he also has three US patents on medical imaging applications. Matti is

  10. Setting the Scene--Introduction to Quality in Peer Production of eLearning

    ERIC Educational Resources Information Center

    Auvinen, Ari-Matti

    2008-01-01

    The "Setting the scene" deliverable of the QMPP project (www.qmpp.net) has been authored by Mr. Ari-Matti Auvinen (HCI Productions Oy) and many QMPP project partners. In addition to the definition of the scope of the project, it includes also a good list of references to the literature of user-generated content as well as good web links to…

  11. Translational mass of an exciton

    NASA Astrophysics Data System (ADS)

    Cafolla, A. A.; Schnatterly, S. E.; Tarrio, C.

    1985-12-01

    From transmission electron-energy-loss measurements we show that the mass of an exciton M* is greater than the sum of the effective masses of the electron and hole me+mh. This result is consistent with a recent prediction by Mattis and Gallinar.

  12. Foreign Language Anxiety and Oral Exam Performance: A Replication of Phillips's "MLJ" Study

    ERIC Educational Resources Information Center

    Hewitt, Elaine; Stephenson, Jean

    2012-01-01

    This article reports on a replication study of a substantial piece of research published in "The Modern Language Journal", carried out by Elaine Matties Phillips in 1992, and entitled "The Effects of Language Anxiety on Students' Oral Test Performance and Attitudes." The aim of both studies was to assess the influence of language anxiety…

  13. 75 FR 80850 - Development of Strategic Plan 2011-2015

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-23

    ... welcomes comments on GPRA as a model for LSC as well as suggestions for other strategic planning models and.... ADDRESSES: Written comments may be submitted by mail, fax or e-mail to Mattie Cohan, Senior Assistant... regarding whether and how LSC may incorporate performance measures into its strategic planning efforts....

  14. Benchmarking Peer Production Mechanisms, Processes & Practices

    ERIC Educational Resources Information Center

    Fischer, Thomas; Kretschmer, Thomas

    2008-01-01

    This deliverable identifies key approaches for quality management in peer production by benchmarking peer production practices and processes in other areas. (Contains 29 footnotes, 13 figures and 2 tables.)[This report has been authored with contributions of: Kaisa Honkonen-Ratinen, Matti Auvinen, David Riley, Jose Pinzon, Thomas Fischer, Thomas…

  15. Bile pigments: newcomers to the cell signaling arena.

    PubMed

    Maines, Mahin D

    2003-01-01

    The article highlighted in this issue is "2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)-Induced Accumulation of Biliverdin and Hepatic Peliosis in Rats," by Marjo Nittynen, Jouni T. Tuomisto, Seppo Auriola, Raimo Pohjanvirta, Paula Syrjälä, Ulla Simanainen, Matti Viluksela, and Jouko Tuomisto (pp. 112-123).

  16. Learning Science through Talking Science in Elementary Classroom

    ERIC Educational Resources Information Center

    Tank, Kristina Maruyama; Coffino, Kara

    2014-01-01

    Elementary students in grade two make sense of science ideas and knowledge through their contextual experiences. Mattis Lundin and Britt Jakobson find in their research that early grade students have sophisticated understandings of human anatomy and physiology. In order to understand what students' know about human body and various systems,…

  17. The Historical Justification of Music

    ERIC Educational Resources Information Center

    Huttunen, Matti

    2008-01-01

    The article deals with various aspects of justifying music historically. In Matti Huttunen's opinion Western music culture has been strongly historical since the nineteenth century. The article attempts to elucidate the historical nature of music, as well as the canon of music, the selective nature of music history, and the influence of aesthetic…

  18. Nontrivial ferrimagnetism of the Heisenberg model on the Union Jack strip lattice

    NASA Astrophysics Data System (ADS)

    Shimokawa, Tokuro; Nakano, Hiroki

    2013-08-01

    We study the ground-state properties of the S = 1/2 antiferromagnetic Heisenberg model on the Union Jack strip lattice by using the exact-diagonalization and density matrix renormalization group methods. We confirm a region of a magnetization state intermediate between the Néel-like spin liquid state and the conventional ferrimagnetic state of a Lieb-Mattis type. In the intermediate state, we find that the spontaneous magnetization changes gradually with respect to the strength of the inner interaction. In addition, the local magnetization clearly shows an incommensurate modulation with long-distance periodicity in the intermediate magnetization state. These characteristic behaviors lead to the conclusion that the intermediate magnetization state is a non-Lieb-Mattis ferrimagnetic one. We also discuss the relationship between the ground-state properties of the S = 1/2 antiferromagnetic Heisenberg model on the original Union Jack lattice and those on our strip lattice.

  19. Drone-fermions in the two-dimensional antiferromagnet

    NASA Astrophysics Data System (ADS)

    Krivenko, S.; Khaliullin, G.

    1995-02-01

    Two different representations of spins - via the conventional fermions, or via the Mattis drone-fermions - are compared considering the planar antiferromagnetic Heisenberg model as an example. Mean-field spin correlation functions calculated for the uniform and flux RVB states show that the drone-fermion approach has an advantage in giving the lower energy and the enhanced AF correlations, because of the absence of unphysical spinless states in this representation.

  20. Extension of Lieb-Schupp theorem to Heisenberg models with higher-order interactions

    NASA Astrophysics Data System (ADS)

    Tanaka, Kengo

    2016-10-01

    We extend the Lieb-Schupp theorem to Heisenberg models with higher-order interactions on nonfrustrated or frustrated finite lattices. These lattices are constructed by even-numbered rings with or without crossing bonds and have reflection symmetry. The results show that the ground state has total spin zero in wide interaction parameter regions which are not covered by the results of Marshall-Lieb-Mattis-type arguments.

  1. Nontrivial ferrimagnetism on the low-dimensional quantum spin systems with frustration

    NASA Astrophysics Data System (ADS)

    Shimokawa, Tokuro; Nakano, Hiroki; Sakai, Toru

    2013-03-01

    In low-dimensional quantum spin systems with frustration, nontrivial magnetisms often occur due to strong quantum fluctuation. Ferrimagnetism in non-frustrated systems is well-known to occur from the mechanism based on the Marshall-Lieb-Mattis theorem. This type of ferrimagnetism is called ``Lieb-Mattis (LM) type.'' Recently, the occurrence of nontrivial ferrimagnetism has been reported in some one-dimensional Heisenberg spin systems with frustration, in which the continuous change of spontaneous magnetization and the incommensurate modulation in local magnetization are observed. This type is called ``non-Lieb-Mattis (NLM) type.'' In this study, we tackle a problem whether the NLM ferrimagnetism occurs or not in higher dimensional systems. We investigate the S =1/2 Heisenberg models on the spatially anisotropic two-dimensional (2D) kagome lattice and on the quasi-one-dimensional (Q1D) kagome strip lattices by the numerical diagonalization and density matrix renormalization group methods. The Q1D models share the same structure in their inner part with the spatially anisotropic 2D kagome lattice; we examine two cases with respect to strip width. We will discuss the relationship between the ground-state properties of the Q1D lattices and those of the 2D lattice.

  2. Temperature dependence of far-infrared difference reflectivity of YBa2Cu3O7-y

    NASA Astrophysics Data System (ADS)

    Krenn, H.; Bauer, G.; Vogl, G.; Strasser, G.; Gornik, E.

    1989-04-01

    Far-infrared difference reflectivity spectra (50-450 cm-1) below, across and above the transition temperature on polycrystalline single-phase YBa2Cu3O7-y samples were measured. The data are compared with model fits using the explicit temperature dependence of the Mattis-Bardeen conductivity, an effective-medium approach and temperature-dependent phonon oscillator parameters and alternatively a plasma model. For the plasma model we alternatively use a generalized Drude-like expression with a frequency-dependent damping after Thomas et al. [Phys. Rev. B 36, 846 (1987)] or the original model with Orenstein et al. [Phys. Rev. B 36, 729 (1987)] and Sherwin, Richards, and Zettl [Phys. Rev. B 37, 1587 (1988)] with a Drude contribution plus a mid-infrared oscillator, but with constant carrier relaxation rates. The models explain the difference reflectivity data (precision <0.2%) with a fitting accuracy of 1-2 % (Mattis-Bardeen model) or 2-3 % (plasma model) over the full temperature range. In order to investigate their applicability, reflectivity, and conductivity data of a highly oriented YBa2Cu3O7-y sample, as recently published by Bonn et al. [Phys. Rev. Lett. 58, 2249 (1987)], were also fitted with both models. Because of the frequency dependence of the free-carrier damping rates, it was important to fulfill the Kramers-Kronig relations between the real and the imaginary part of the dynamic conductivity in the calculations. For both models the characteristic dependences of the conductivity on frequency and temperature are given. Whereas, naturally, the Mattis-Bardeen model yields a gaplike depression of the conductivity for frequencies below an assumed gap, the plasma model results in somewhat smoother dependences of Re(σ(ω)) and Im(σ(ω)) in the frequency region of interest.

  3. Non-uniform absorption of terahertz radiation on superconducting hot electron bolometer microbridges

    SciTech Connect

    Miao, W.; Zhang, W.; Zhong, J. Q.; Shi, S. C.; Delorme, Y.; Lefevre, R.; Feret, A.; Vacelet, T.

    2014-02-03

    We interpret the experimental observation of a frequency-dependence of superconducting hot electron bolometer (HEB) mixers by taking into account the non-uniform absorption of the terahertz radiation on the superconducting HEB microbridge. The radiation absorption is assumed to be proportional to the local surface resistance of the HEB microbridge, which is computed using the Mattis-Bardeen theory. With this assumption the dc and mixing characteristics of a superconducting niobium-nitride (NbN) HEB device have been modeled at frequencies below and above the equilibrium gap frequency of the NbN film.

  4. Finite quasiparticle lifetime in disordered superconductors

    NASA Astrophysics Data System (ADS)

    Žemlička, M.; Neilinger, P.; Trgala, M.; Rehák, M.; Manca, D.; Grajcar, M.; Szabó, P.; Samuely, P.; Gaži, Š.; Hübner, U.; Vinokur, V. M.; Il'ichev, E.

    2015-12-01

    We investigate the complex conductivity of a highly disordered MoC superconducting film with kFl ≈1 , where kF is the Fermi wave number and l is the mean free path, derived from experimental transmission characteristics of coplanar waveguide resonators in a wide temperature range below the superconducting transition temperature Tc. We find that the original Mattis-Bardeen model with a finite quasiparticle lifetime, τ , offers a perfect description of the experimentally observed complex conductivity. We show that τ is appreciably reduced by scattering effects. Characteristics of the scattering centers are independently found by scanning tunneling spectroscopy and agree with those determined from the complex conductivity.

  5. Theory of disordered unconventional superconductors

    SciTech Connect

    Keles, A.; Andreev, A. V.; Spivak, B. Z.; Kivelson, S. A.

    2014-12-15

    In contrast to conventional s-wave superconductivity, unconventional (e.g., p- or d-wave) superconductivity is strongly suppressed even by relatively weak disorder. Upon approaching the superconductormetal transition, the order parameter amplitude becomes increasingly inhomogeneous, leading to effective granularity and a phase ordering transition described by the Mattis model of spin glasses. One consequence of this is that at sufficiently low temperatures, between the clean unconventional superconducting and the diffusive metallic phases, there is necessarily an intermediate superconducting phase that exhibits s-wave symmetry on macroscopic scales.

  6. Some of the Seminars Given during the Session

    NASA Astrophysics Data System (ADS)

    Balian, Roger; Maynard, Roger; Toulouse, Gerard

    The following sections are included: * ATOMIC STRUCTURE OF AMORPHOUS BODIES * ABOUT SPIN GLASSES AND OTHER GLASSES * STUDY OF THE DELOCALIZATION OF THE ELECTRONS IN n-CdS AROUND THE MOTT TRANSITION BY SPIN FLIP RAMAN SCATTERING AND FARADAY ROTATION * A QUADRUPOLAR GLASS PHASE IN SOLID HYDROGEN * AMORPHOUS SILICON AND ITS APPLICATION TO SEMICONDUCTOR DEVICES * EXCITATIONS IN THE HEISENBERG-MATTIS MODEL: NON-TRIVIAL OSCILLATIONS ON A FLAT BACKGROUND * THRESHOLD CONDUCTION IN INVERSION LAYERS * ELECTRONIC PROCESSES IN GLASSY SEMICONDUCTORS* * DO THE PROPERTIES OF SPIN GLASSES DEPEND ON THE SPIN DIMENSIONALITY? * CONFORMATION DES POLYMÉRES EN SOLUTION * NEUTRONS ET COHÉRENCES

  7. Magnetization plateaux in Bethe ansatz solvable spin-S ladders

    NASA Astrophysics Data System (ADS)

    Maslen, M.; Batchelor, M.; de Gier, J.

    2003-07-01

    We examine the properties of the Bethe ansatz solvable two- and three-leg spin-S ladders. These models include Heisenberg rung interactions of arbitrary strength and thus capture the physics of the spin-S Heisenberg ladders for strong rung coupling. The discrete values derived for the magnetization plateaux are seen to fit with the general prediction based on the Lieb-Schultz-Mattis theorem. We examine the magnetic phase diagram of the spin-1 ladder in detail and find an extended magnetization plateau at the fractional value =1/2 in agreement with the experimental observation for the organic polyradical spin-1 ladder compound BIP-TENO.

  8. Order Parameter to Characterize Valence-Bond-Solid States in Quantum Spin Chains

    NASA Astrophysics Data System (ADS)

    Nakamura, Masaaki; Todo, Synge

    2003-03-01

    We propose an order parameter to characterize valence-bond-solid (VBS) states in quantum spin chains, given by the ground-state expectation value of a unitary operator appearing in the Lieb-Schultz-Mattis argument. We show that the order parameter changes the sign according to the number of valence bonds (broken valence bonds) at the boundary for periodic (open) systems. This allows us to determine the phase transition point in between different VBS states. We demonstrate this theory in the successive dimerization transitions of the bond-alternating Heisenberg chains and spin ladders using the quantum Monte Carlo method.

  9. Chalker-Coddington Network Model is Quantum Critical

    NASA Astrophysics Data System (ADS)

    Marston, J. B.; Tsai, Shan-Wen

    1999-06-01

    We show that the localization transition in the integer quantum Hall effect as described by the Chalker-Coddington network model is quantum critical. We first map the anisotropic network model to the problem of diagonalizing a one-dimensional non-Hermitian noncompact supersymmetric lattice Hamiltonian of interacting bosons and fermions. Its behavior is investigated numerically using the density matrix renormalization group method, and critical behavior is found at the plateau transition. This result is confirmed by a generalization of the Lieb-Schultz-Mattis theorem.

  10. Order Parameter to Characterize Valence-Bond-Solid States in Quantum Spin Chains

    NASA Astrophysics Data System (ADS)

    Nakamura, Masaaki; Todo, Synge

    2002-07-01

    We propose an order parameter to characterize valence-bond-solid (VBS) states in quantum spin chains, given by the ground-state expectation value of a unitary operator appearing in the Lieb-Schultz-Mattis argument. We show that the order parameter changes the sign according to the number of valence bonds (broken valence bonds) at the boundary for periodic (open) systems. This allows us to determine the phase transition point in between different VBS states. We demonstrate this theory in the successive dimerization transitions of the bond-alternating Heisenberg chains, using the quantum Monte Carlo method.

  11. Properties of the first excited state of nonbipartite Heisenberg spin rings

    NASA Astrophysics Data System (ADS)

    Schnack, J.

    2000-12-01

    Systematic properties of the first excited state are presented for various ring sizes and spin quantum numbers which are only partly covered by the theorem of Lieb, Schultz, and Mattis. For odd ring sizes the first excited energy eigenvalue shows unexpected degeneracy and related shift quantum numbers. As a byproduct the ground state energy as well as the energy of the first excited state of infinite chains are calculated by extrapolating the properties of only a few, finite, antiferromagnetically coupled Heisenberg rings using the powerful Levin sequence acceleration method.

  12. Sizing up the competition: quantifying the influence of the mental lexicon on auditory and visual spoken word recognition.

    PubMed

    Strand, Julia F; Sommers, Mitchell S

    2011-09-01

    Much research has explored how spoken word recognition is influenced by the architecture and dynamics of the mental lexicon (e.g., Luce and Pisoni, 1998; McClelland and Elman, 1986). A more recent question is whether the processes underlying word recognition are unique to the auditory domain, or whether visually perceived (lipread) speech may also be sensitive to the structure of the mental lexicon (Auer, 2002; Mattys, Bernstein, and Auer, 2002). The current research was designed to test the hypothesis that both aurally and visually perceived spoken words are isolated in the mental lexicon as a function of their modality-specific perceptual similarity to other words. Lexical competition (the extent to which perceptually similar words influence recognition of a stimulus word) was quantified using metrics that are well-established in the literature, as well as a statistical method for calculating perceptual confusability based on the phi-square statistic. Both auditory and visual spoken word recognition were influenced by modality-specific lexical competition as well as stimulus word frequency. These findings extend the scope of activation-competition models of spoken word recognition and reinforce the hypothesis (Auer, 2002; Mattys et al., 2002) that perceptual and cognitive properties underlying spoken word recognition are not specific to the auditory domain. In addition, the results support the use of the phi-square statistic as a better predictor of lexical competition than metrics currently used in models of spoken word recognition.

  13. Effect of interstitial impurities on the field dependent microwave surface resistance of niobium

    NASA Astrophysics Data System (ADS)

    Martinello, M.; Grassellino, A.; Checchin, M.; Romanenko, A.; Melnychuk, O.; Sergatskov, D. A.; Posen, S.; Zasadzinski, J. F.

    2016-08-01

    Previous work has demonstrated that the radio frequency surface resistance of niobium resonators is dramatically reduced when nitrogen impurities are dissolved as interstitial in the material. This effect is attributed to the lowering of the Mattis-Bardeen surface resistance with increasing accelerating field; however, the microscopic origin of this phenomenon is poorly understood. Meanwhile, an enhancement of the sensitivity to trapped magnetic field is typically observed for such cavities. In this paper, we conduct a systematic study on these different components contributing to the total surface resistance as a function of different levels of dissolved nitrogen, in comparison with standard surface treatments for niobium resonators. Adding these results together, we are able to show which is the optimum surface treatment that maximizes the Q-factor of superconducting niobium resonators as a function of expected trapped magnetic field in the cavity walls. These results also provide insights on the physics behind the change in the field dependence of the Mattis-Bardeen surface resistance, and of the trapped magnetic vortex induced losses in superconducting niobium resonators.

  14. Finite quasiparticle lifetime in disordered superconductors.

    SciTech Connect

    Zemlicka, M.; Neilinger, P.; Trgala, M; Rehak, M; Manca, D.; Grajcar, M.; Szabo, P.; Samuely, P.; Gazi, S.; Hubner, U.; Vinokur, V. M.; Il'ichev, E.

    2015-12-08

    We investigate the complex conductivity of a highly disordered MoC superconducting film with k(F)l approximate to 1, where k(F) is the Fermi wave number and l is the mean free path, derived from experimental transmission characteristics of coplanar waveguide resonators in a wide temperature range below the superconducting transition temperature T-c. We find that the original Mattis-Bardeen model with a finite quasiparticle lifetime, tau, offers a perfect description of the experimentally observed complex conductivity. We show that iota is appreciably reduced by scattering effects. Characteristics of the scattering centers are independently found by scanning tunneling spectroscopy and agree with those determined from the complex conductivity.

  15. Quantum annealing for the number-partitioning problem using a tunable spin glass of ions

    NASA Astrophysics Data System (ADS)

    Graß, Tobias; Raventós, David; Juliá-Díaz, Bruno; Gogolin, Christian; Lewenstein, Maciej

    2016-05-01

    Exploiting quantum properties to outperform classical ways of information processing is an outstanding goal of modern physics. A promising route is quantum simulation, which aims at implementing relevant and computationally hard problems in controllable quantum systems. Here we demonstrate that in a trapped ion setup, with present day technology, it is possible to realize a spin model of the Mattis-type that exhibits spin glass phases. Our method produces the glassy behaviour without the need for any disorder potential, just by controlling the detuning of the spin-phonon coupling. Applying a transverse field, the system can be used to benchmark quantum annealing strategies which aim at reaching the ground state of the spin glass starting from the paramagnetic phase. In the vicinity of a phonon resonance, the problem maps onto number partitioning, and instances which are difficult to address classically can be implemented.

  16. Constraints on topological order in mott insulators.

    PubMed

    Zaletel, Michael P; Vishwanath, Ashvin

    2015-02-20

    We point out certain symmetry induced constraints on topological order in Mott insulators (quantum magnets with an odd number of spin 1/2 moments per unit cell). We show, for example, that the double-semion topological order is incompatible with time reversal and translation symmetry in Mott insulators. This sharpens the Hastings-Oshikawa-Lieb-Schultz-Mattis theorem for 2D quantum magnets, which guarantees that a fully symmetric gapped Mott insulator must be topologically ordered, but is silent about which topological order is permitted. Our result applies to the kagome lattice quantum antiferromagnet, where recent numerical calculations of the entanglement entropy indicate a ground state compatible with either toric code or double-semion topological order. Our result rules out the latter possibility.

  17. A 850 GHz SIS receiver employing silicon micro-machining technology

    NASA Technical Reports Server (NTRS)

    Kooi, J. W.; Pety, J.; Schaffer, P. L.; Phillips, T. G.; Bumble, B.; LeDuc, H. G.; Walker, C. K.

    1996-01-01

    A 850 GHz superconductor-insulator-superconductor (SIS) heterodyne receiver which uses a radiofrequency tuned niobium tunnel junction fabricated on a 1 micron thick silicon nitrate membrane, is reported. From video and heterodyne measurements, it was calculated that the niobium film loss in the radiofrequency matching network is about 6.8 dB at 822 GHz. These results are approximately a factor of two higher than the theoretical loss predicted by the Mattis-Bardeen theory in the extreme anomalous limit. The junction design and the receiver configuration are described, including the mixer block, the membrane construction and the cooled optics. The performance tests using a Fourier transform spectrometer to measure the response of the radiofrequency matching network, and the SIS simulations of the receiver response to cold and hot loads, the infrared noise contribution and the overall mixer conversion efficiency, are reported. It is concluded that the receiver response is limited by the absorption loss in the radiofrequency matching network.

  18. FINEMAP: efficient variable selection using summary data from genome-wide association studies

    PubMed Central

    Benner, Christian; Spencer, Chris C.A.; Havulinna, Aki S.; Salomaa, Veikko; Ripatti, Samuli; Pirinen, Matti

    2016-01-01

    Motivation: The goal of fine-mapping in genomic regions associated with complex diseases and traits is to identify causal variants that point to molecular mechanisms behind the associations. Recent fine-mapping methods using summary data from genome-wide association studies rely on exhaustive search through all possible causal configurations, which is computationally expensive. Results: We introduce FINEMAP, a software package to efficiently explore a set of the most important causal configurations of the region via a shotgun stochastic search algorithm. We show that FINEMAP produces accurate results in a fraction of processing time of existing approaches and is therefore a promising tool for analyzing growing amounts of data produced in genome-wide association studies and emerging sequencing projects. Availability and implementation: FINEMAP v1.0 is freely available for Mac OS X and Linux at http://www.christianbenner.com. Contact: christian.benner@helsinki.fi or matti.pirinen@helsinki.fi PMID:26773131

  19. The Spin Glass-Kondo Competition in Disordered Cerium Systems

    NASA Astrophysics Data System (ADS)

    Magalhaes, S. G.; Zimmer, F.; Coqblin, B.

    2013-10-01

    We discuss the competition between the Kondo effect, the spin glass state and a magnetic order observed in disordered Cerium systems. We present firstly the experimental situation of disordered alloys such as CeNi1 - xCux and then the different theoretical approaches based on the Kondo lattice model, with different descriptions of the intersite exchange interaction for the spin glass. After the gaussian approach of the Sherrington-Kirkpatrick model, we discuss the Mattis and the van Hemmen models. Then, we present simple cluster calculations in order to describe the percolative evolution of the clusters from the cluster spin glass to the inhomogeneous ferromagnetic order recently observed in CeNi1 - xCux disordered alloys and finally we discuss the effect of random and transverse magnetic field.

  20. Learning science through talking science in elementary classroom

    NASA Astrophysics Data System (ADS)

    Tank, Kristina Maruyama; Coffino, Kara

    2014-03-01

    Elementary students in grade two make sense of science ideas and knowledge through their contextual experiences. Mattis Lundin and Britt Jakobson find in their research that early grade students have sophisticated understandings of human anatomy and physiology. In order to understand what students' know about human body and various systems, both drawings and spoken responses provide rich evidence of their understanding of the connections between science drawings and verbal explanations. In this forum contribution, we present several theoretical connections between everyday language and science communication and argue that building communication skills in science are essential. We also discuss how young participants should be valued and supported in research. Finally we discuss the need for multimodal research methods when the research participants are young.

  1. Constraints on topological order in mott insulators.

    PubMed

    Zaletel, Michael P; Vishwanath, Ashvin

    2015-02-20

    We point out certain symmetry induced constraints on topological order in Mott insulators (quantum magnets with an odd number of spin 1/2 moments per unit cell). We show, for example, that the double-semion topological order is incompatible with time reversal and translation symmetry in Mott insulators. This sharpens the Hastings-Oshikawa-Lieb-Schultz-Mattis theorem for 2D quantum magnets, which guarantees that a fully symmetric gapped Mott insulator must be topologically ordered, but is silent about which topological order is permitted. Our result applies to the kagome lattice quantum antiferromagnet, where recent numerical calculations of the entanglement entropy indicate a ground state compatible with either toric code or double-semion topological order. Our result rules out the latter possibility. PMID:25763971

  2. Quantum annealing for the number-partitioning problem using a tunable spin glass of ions.

    PubMed

    Graß, Tobias; Raventós, David; Juliá-Díaz, Bruno; Gogolin, Christian; Lewenstein, Maciej

    2016-01-01

    Exploiting quantum properties to outperform classical ways of information processing is an outstanding goal of modern physics. A promising route is quantum simulation, which aims at implementing relevant and computationally hard problems in controllable quantum systems. Here we demonstrate that in a trapped ion setup, with present day technology, it is possible to realize a spin model of the Mattis-type that exhibits spin glass phases. Our method produces the glassy behaviour without the need for any disorder potential, just by controlling the detuning of the spin-phonon coupling. Applying a transverse field, the system can be used to benchmark quantum annealing strategies which aim at reaching the ground state of the spin glass starting from the paramagnetic phase. In the vicinity of a phonon resonance, the problem maps onto number partitioning, and instances which are difficult to address classically can be implemented. PMID:27230802

  3. Exact density profiles and symmetry classification for strongly interacting multi-component Fermi gases in tight waveguides

    NASA Astrophysics Data System (ADS)

    Decamp, Jean; Armagnat, Pacome; Fang, Bess; Albert, Mathias; Minguzzi, Anna; Vignolo, Patrizia

    2016-05-01

    We consider a mixture of one-dimensional strongly interacting Fermi gases with up to six components, subjected to a longitudinal harmonic confinement. In the limit of infinitely strong repulsions we provide an exact solution which generalizes the one for the two-component mixture. We show that an imbalanced mixture under harmonic confinement displays partial spatial separation among the components, with a structure which depends on the relative population of the various components. Furthermore, we provide a symmetry characterization of the ground and excited states of the mixture introducing and evaluating a suitable operator, namely the conjugacy class sum. We show that, even under external confinement, the gas has a definite symmetry which corresponds to the most symmetric one compatible with the imbalance among the components. This generalizes the predictions of the Lieb-Mattis theorem for a Fermionic mixture with more than two components.

  4. A New First-Principles Calculation of Field-Dependent RF Surface Impedance of BCS Superconductor

    SciTech Connect

    Xiao, Binping; Reece, Charles E.

    2014-02-01

    There is a need to understand the intrinsic limit of radiofrequency (RF) surface impedance that determines the performance of superconducting RF cavities in particle accelerators. Here we present a field-dependent derivation of Mattis-Bardeen theory of the RF surface impedance of BCS superconductors based on the shifted density of states resulting from coherently moving Cooper pairs. Our theoretical prediction of the effective BCS RF surface resistance (Rs) of niobium as a function of peak surface magnetic field amplitude agrees well with recently reported record low loss resonant cavity measurements from JLab and FNAL with carefully, yet differently, prepared niobium material. The surprising reduction in resistance with increasing field is explained to be an intrinsic effect.

  5. Update on Service Management project

    SciTech Connect

    2011-02-28

    GS and IT Service Management project status meeting -------------------------------------------------------------------------- Distribution: Sigurd Lettow, Frederic Hemmer, Thomas Pettersson, David Foster, Matti Tiirakari, GS&IT; Service Providers When and where: Thursday 2nd September at 10:00-11:30 in IFiltration Plant (222-R-001) Dear All, We would like to inform you about progress made on different topics like the Service Catalogue, the new Service Management Tool and the Service Desk. We would also like to present the plan for when we hope to "go live" and what this will mean for all of you running and providing services today. We will need your active support and help in the coming months to make this happen. GS&IT; Service Management Teams Reinoud Martens, Mats Moller

  6. Update on Service Management project

    ScienceCinema

    None

    2016-07-12

    GS and IT Service Management project status meeting -------------------------------------------------------------------------- Distribution: Sigurd Lettow, Frederic Hemmer, Thomas Pettersson, David Foster, Matti Tiirakari, GS&IT; Service Providers When and where: Thursday 2nd September at 10:00-11:30 in IFiltration Plant (222-R-001) Dear All, We would like to inform you about progress made on different topics like the Service Catalogue, the new Service Management Tool and the Service Desk. We would also like to present the plan for when we hope to "go live" and what this will mean for all of you running and providing services today. We will need your active support and help in the coming months to make this happen. GS&IT; Service Management Teams Reinoud Martens, Mats Moller

  7. Lattice twist operators and vertex operators in sine-Gordon theory in one dimension

    NASA Astrophysics Data System (ADS)

    Nakamura, Masaaki; Voit, Johannes

    2002-04-01

    In one dimension, the exponential position operators introduced in a theory of polarization are identified with the twist operators appearing in the Lieb-Schultz-Mattis argument, and their finite-size expectation values z(q)L measure the overlap between the q-fold degenerate ground state and an excited state. Insulators are characterized by z∞≠0, and different states are distinguished by the sign of zL. We identify zL with ground-state expectation values of vertex operators in the sine-Gordon model. This allows an accurate detection of quantum phase transitions in the universality classes of the Gaussian and the SU(2)1 Wess-Zumino-Novikov-Witten models. We apply this theory to the half-filled extended Hubbard model and obtain agreement with the level-crossing method.

  8. Entanglement and quantum phase transition in the Heisenberg—Ising model

    NASA Astrophysics Data System (ADS)

    Tan, Xiao-Dong; Jin, Bai-Qi; Gao, Wei

    2013-02-01

    We use the quantum renormalization-group (QRG) method to study the entanglement and quantum phase transition (QPT) in the one-dimensional spin-1/2 Heisenberg—Ising model [Lieb E, Schultz T and Mattis D 1961 Ann. Phys. (N.Y.) 16 407]. We find the quantum phase boundary of this model by investigating the evolution of concurrence in terms of QRG iterations. We also investigate the scaling behavior of the system close to the quantum critical point, which shows that the minimum value of the first derivative of concurrence and the position of the minimum scale with an exponent of the system size. Also, the first derivative of concurrence between two blocks diverges at the quantum critical point, which is directly associated with the divergence of the correlation length.

  9. Quantum annealing for the number-partitioning problem using a tunable spin glass of ions

    PubMed Central

    Graß, Tobias; Raventós, David; Juliá-Díaz, Bruno; Gogolin, Christian; Lewenstein, Maciej

    2016-01-01

    Exploiting quantum properties to outperform classical ways of information processing is an outstanding goal of modern physics. A promising route is quantum simulation, which aims at implementing relevant and computationally hard problems in controllable quantum systems. Here we demonstrate that in a trapped ion setup, with present day technology, it is possible to realize a spin model of the Mattis-type that exhibits spin glass phases. Our method produces the glassy behaviour without the need for any disorder potential, just by controlling the detuning of the spin-phonon coupling. Applying a transverse field, the system can be used to benchmark quantum annealing strategies which aim at reaching the ground state of the spin glass starting from the paramagnetic phase. In the vicinity of a phonon resonance, the problem maps onto number partitioning, and instances which are difficult to address classically can be implemented. PMID:27230802

  10. All Majorana Models with Translation Symmetry are Supersymmetric

    NASA Astrophysics Data System (ADS)

    Hsieh, Timothy H.; Halász, Gábor B.; Grover, Tarun

    2016-10-01

    We establish results similar to Kramers and Lieb-Schultz-Mattis theorems but involving only translation symmetry and for Majorana modes. In particular, we show that all states are at least doubly degenerate in any one- and two-dimensional array of Majorana modes with translation symmetry, periodic boundary conditions, and an odd number of modes per unit cell. Moreover, we show that all such systems have an underlying N =2 supersymmetry and explicitly construct the generator of the supersymmetry. Furthermore, we establish that there cannot be a unique gapped ground state in such one-dimensional systems with antiperiodic boundary conditions. These general results are fundamentally a consequence of the fact that translations for Majorana modes are represented projectively, which in turn stems from the anomalous nature of a single Majorana mode. An experimental signature of the degeneracy arising from supersymmetry is a zero-bias peak in tunneling conductance.

  11. Existence of featureless paramagnets on the square and the honeycomb lattices in 2+1 dimensions

    NASA Astrophysics Data System (ADS)

    Jian, Chao-Ming; Zaletel, Michael

    2016-01-01

    The peculiar features of quantum magnetism sometimes forbid the existence of gapped "featureless" paramagnets which are fully symmetric and unfractionalized. The Lieb-Schultz-Mattis theorem is an example of such a constraint, but it is not known what the most general restriction might be. We focus on the existence of featureless paramagnets on the spin-1 square lattice and the spin-1 and spin-1/2 honeycomb lattice with spin rotation and space group symmetries in 2+1 dimensions. Although featureless paramagnet phases are not ruled out by any existing theorem, field theoretic arguments disfavor their existence. Nevertheless, by generalizing the construction of Affleck, Kennedy, Lieb, and Tasaki to a class we call "slave-spin" states, we propose featureless wave functions for these models. The featurelessness of the spin-1 slave-spin states on the square and honeycomb lattice are verified both analytically and numerically, but the status of the spin-1/2 honeycomb state remains unclear.

  12. Temperature dependence of far-infrared difference reflectivity of YBa/sub 2/Cu/sub 3/O/sub 7-//sub y/

    SciTech Connect

    Krenn, H.; Bauer, G.; Vogl, G.; Strasser, G.; Gornik, E.

    1989-04-01

    Far-infrared difference reflectivity spectra (50--450 cm/sup -1/) below, across and above the transition temperature on polycrystalline single-phase YBa/sub 2/Cu/sub 3/O/sub 7-//sub y/ samples were measured. The data are compared with model fits using the explicit temperature dependence of the Mattis-Bardeen conductivity, an effective-medium approach and temperature-dependent phonon oscillator parameters and alternatively a plasma model. For the plasma model we alternatively use a generalized Drude-like expression with a frequency-dependent damping after Thomas et al. (Phys. Rev. B 36, 846 (1987)) or the original model with Orenstein et al. (Phys. Rev. B 36, 729 (1987)) and Sherwin, Richards, and Zettl (Phys. Rev. B 37, 1587 (1988)) with a Drude contribution plus a mid-infrared oscillator, but with constant carrier relaxation rates. The models explain the difference reflectivity data (precision <0.2%) with a fitting accuracy of 1--2 % (Mattis-Bardeen model) or 2--3 % (plasma model) over the full temperature range. In order to investigate their applicability, reflectivity, and conductivity data of a highly oriented YBa/sub 2/Cu/sub 3/O/sub 7-//sub y/ sample, as recently published by Bonn et al. (Phys. Rev. Lett. 58, 2249 (1987)), were also fitted with both models. Because of the frequency dependence of the free-carrier damping rates, it was important to fulfill the Kramers-Kronig relations between the real and the imaginary part of the dynamic conductivity in the calculations. For both models the characteristic dependences of the conductivity on frequency and temperature are given.

  13. Geologic map and digital database of the Cougar Buttes 7.5' quadrangle, San Bernardino County, California

    USGS Publications Warehouse

    Powell, R.E.; Matti, J.C.; Cossette, P.M.

    2000-01-01

    The Southern California Areal Mapping Project (SCAMP) of Geologic Division has undertaken regional geologic mapping investigations in the Lucerne Valley area co-sponsored by the Mojave Water Agency and the San Bernardino National Forest. These investigations span the Lucerne Valley basin from the San Bernardino Mountains front northward to the basin axis on the Mojave Desert floor, and from the Rabbit Lake basin east to the Old Woman Springs area. Quadrangles mapped include the Cougar Buttes 7.5' quadrangle, the Lucerne Valley 7.5' quadrangle (Matti and others, in preparation b), the Fawnskin 7.5' quadrangle (Miller and others, 1998), and the Big Bear City 7.5' quadrangle (Matti and others, in preparation a). The Cougar Buttes quadrangle has been mapped previously at scales of 1:62,500 (Dibblee, 1964) and 1:24,000 (Shreve, 1958, 1968; Sadler, 1982a). In line with the goals of the National Cooperative Geologic Mapping Program (NCGMP), our mapping of the Cougar Buttes quadrangle has been directed toward generating a multipurpose digital geologic map database. Guided by the mapping of previous investigators, we have focused on improving our understanding and representation of late Pliocene and Quaternary deposits. In cooperation with the Water Resources Division of the U.S. Geological Survey, we have used our mapping in the Cougar Buttes and Lucerne Valley quadrangles together with well log data to construct cross-sections of the Lucerne Valley basin (R.E. Powell, unpublished data, 1996-1998) and to develop a hydrogeologic framework for the basin. Currently, our mapping in these two quadrangles also is being used as a base for studying soils on various Quaternary landscape surfaces on the San Bernardino piedmont (Eppes and others, 1998). In the Cougar Buttes quadrangle, we have endeavored to represent the surficial geology in a way that provides a base suitable for ecosystem assessment, an effort that has entailed differentiating surficial veneers on piedmont and

  14. Age and paleoenvironment of the imperial formation near San Gorgonio Pass, Southern California

    USGS Publications Warehouse

    McDougall, K.; Poore, R.Z.; Matti, J.

    1999-01-01

    Microfossiliferous marine sediments of the Imperial Formation exposed in the Whitewater and Cabazon areas, near San Gorgonio Pass, southern California, are late Miocene in age and were deposited at intertidal to outer neritic depths, and possibly upper bathyal depths. A late Miocene age of 7.4 to >6.04 Ma is based on the ranges of age-diagnostic benthic foraminifers (Cassidulina delicata and Uvigerina peregrina), planktic foraminifers (Globigerinoides obliquus, G. extremus, and Globigerina nepenthes; zones N17-N19), and calcareous nannoplankton (Discoaster brouweri, D. aff. D. surculus, Reticulofenestra pseudoumbilicata, Sphenolithus abies, and S. neoabies; zones CN9a-CN11) coupled with published K/Ar dates from the underlying Coachella Formation (10.1 ?? 1.2 Ma; Peterson, 1975) and overlying Painted Hill Formation (6.04 ?? 0.18 and 5.94 ?? 0.18 Ma; J. L. Morton in Matti and others, 1985 and Matti and Morton, 1993). Paleoecologic considerations (sea-level fluctuations and paleotemperature) restrict the age of the Imperial Formation to 6.5 through 6.3 Ma. Benthic foraminiferal assemblages indicate that the Imperial Formation in the Whitewater and Cabazon sections accumulated at inner neritic to outer neritic (0-152 m) and possibly upper bathyal (152-244 m) depths. Shallowing to inner neritic depths occurred as the upper part of the section was deposited. This sea-level fluctuation corresponds to a global highstand at 6.3 Ma (Haq and others, 1987). Planktic foraminifers suggest an increase in surface-water temperatures upsection. A similar increase in paleotemperatures is interpreted for the North Pacific from 6.5 to 6.3 Ma (warm interval W10 of Barron and Keller, 1983). Environmental contrasts between the Whitewater and Cabazon sections of the Imperial Formation provide evidence for right-lateral displacements on the Banning fault, a late Miocene strand of the San Andreas fault system. The Cabazon section lies south of the Banning fault, and has been displaced west

  15. Spin fluctations and heavy fermions in the Kondo lattice

    SciTech Connect

    Khaliullin, G.G.

    1994-09-01

    This paper studies the spectrum of the spin and electronic excitations of the Kondo lattice at low temperatures. To avoid unphysical states, the Mattis {open_quotes}drone{close_quotes}-fermion representation for localized spins is employed. First, the known Fermi liquid properties of a single impurity are examined. The behavior of the correlator between a localized spin and the electron spin density at large distances shows that the effective interaction between electrons on the Fermi level and low-energy localized spin fluctuations scales as {rho}{sup {minus}1}, where {rho} is the band-state density. This fact is developed into a renormalization of the band spectrum in a periodic lattice. If the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction between localized spins is much smaller than the Kondo fluctuation frequency {omega}{sub k}, the temperature of the crossover to the single-parameter Fermi liquid mode is determined by {omega}{sub k}. When the RKKY interaction becomes of order {omega}{sub k}, there is a new scale {omega}{sub sf}, the energy of the (antiferromagnetic) paramagnon mode, with {omega}{sub sf}{much_lt}{omega}{sub k}. Here the coherent Fermi liquid regime is realized only below a temperature T{sub coh} of order {omega}{sub sf}, while above T{sub coh} quasiparticle damping exhibits a linear temperature dependence. Finally, the nuclear-spin relaxation rate is calculated. 42 refs.

  16. Expectations from preceding prosody influence segmentation in online sentence processing.

    PubMed

    Brown, Meredith; Salverda, Anne Pier; Dilley, Laura C; Tanenhaus, Michael K

    2011-12-01

    Previous work examining prosodic cues in online spoken-word recognition has focused primarily on local cues to word identity. However, recent studies have suggested that utterance-level prosodic patterns can also influence the interpretation of subsequent sequences of lexically ambiguous syllables (Dilley, Mattys, & Vinke, Journal of Memory and Language, 63:274-294, 2010; Dilley & McAuley, Journal of Memory and Language, 59:294-311, 2008). To test the hypothesis that these distal prosody effects are based on expectations about the organization of upcoming material, we conducted a visual-world experiment. We examined fixations to competing alternatives such as pan and panda upon hearing the target word panda in utterances in which the acoustic properties of the preceding sentence material had been manipulated. The proportions of fixations to the monosyllabic competitor were higher beginning 200 ms after target word onset when the preceding prosody supported a prosodic constituent boundary following pan-, rather than following panda. These findings support the hypothesis that expectations based on perceived prosodic patterns in the distal context influence lexical segmentation and word recognition.

  17. Parallel retrieval of correlated patterns: from Hopfield networks to Boltzmann machines.

    PubMed

    Agliari, Elena; Barra, Adriano; De Antoni, Andrea; Galluzzi, Andrea

    2013-02-01

    In this work, we first revise some extensions of the standard Hopfield model in the low storage limit, namely the correlated attractor case and the multitasking case recently introduced by the authors. The former case is based on a modification of the Hebbian prescription, which induces a coupling between consecutive patterns and this effect is tuned by a parameter a. In the latter case, dilution is introduced in pattern entries, in such a way that a fraction d of them is blank. Then, we merge these two extensions to obtain a system able to retrieve several patterns in parallel and the quality of retrieval, encoded by the set of Mattis magnetizations {m(μ)}, is reminiscent of the correlation among patterns. By tuning the parameters d and a, qualitatively different outputs emerge, ranging from highly hierarchical to symmetric. The investigations are accomplished by means of both numerical simulations and statistical mechanics analysis, properly adapting a novel technique originally developed for spin glasses, i.e. the Hamilton-Jacobi interpolation, with excellent agreement. Finally, we show the thermodynamical equivalence of this associative network with a (restricted) Boltzmann machine and study its stochastic dynamics to obtain even a dynamical picture, perfectly consistent with the static scenario earlier discussed.

  18. Paleozoic oolitic ironstones of the Algerian Sahara: a review

    NASA Astrophysics Data System (ADS)

    Guerrak, Salah

    The Paleozoic sediments are present over the greatest part of the SaharanPlatform, from the border of Morocco, Rio de Oro and Mauritania in the W, to the Libyan frontier in the E. They outcrop in the Ougarta chains, the Gourara and the Touat, the Northern border of the Reguibat Shield and constitute a sedimentary girdle around the Touareg Shield, namely the Azzel Matti, the Ahnet, the Mouydir, the Ajjers Tassilis, the Tafassasset Tassilis and the Ouan Ahaggar Tassilis. In all these formations, numerous oolitic ironstones occur, particularly in Ordovician, Devonian and Lower Carboniferous rocks. We can distinguish essentially two types of oolitic ironstones (OIS): OIS with constant thin beds and horizontal extension: they will be named EXID type (Extensive Iron Deposition), and OIS of local extension and irregular thickness: they will be named LOID type (Local Iron Deposition). The EXID type is located in the Ordovician, the Middle Devonian and in the very Lower Carboniferous (Tournaisian) sedimentary rocks. The LOID type occurs in the Lower and Upper Devonian rocks and appears as the economically interesting type. From the Zemmour to the Fezzan, a real Paleozoic oolitic iron belt appears 3000 km long, determining a N Gondwanian oolitic iron province, formed during cold to temperate climates.

  19. MO-B-16A-01: Memorial to Donald D. Tolbert - Memorial Lecture

    SciTech Connect

    Morin, R

    2014-06-15

    The Medical Physics community lost one of its prominent leaders in April, 2013 with the passing of Donald D. Tolbert, PhD. He received his Doctorate at the University of Kansas followed by post Doctoral training at Florida State University and the University of Wisconsin. He was Chief of Radiation Therapy Medical Physics at the University of Wisconsin Hospital for 7 years before relocating to Honolulu Hawaii, where he founded the consulting group Mid-Pacific Medical Physics. Don was a leader in both the AAPM and the ACR, chairing the Professional Council and the Commission on Medical Physics. He was active on the AAPM Board of Directors and a member of the ACR Board of Chancellors. Dr. Tolbert's approach to the difficult problems of the times was admired and respected by colleagues in Medical Physics, Radiation Oncology, and Diagnostic Radiology. He always rose above the heated political rhetoric and led the discussion to higher ground. His wisdom was continually sought to solve complicated problems. Following retirement, he returned to homes in Kansas and Colorado, devoting his time to writing about coping with diabetes and providing support for Seniors in Beloit Kansas. Don is survived by his wife, Mattie, his 3 children and 5 grandchildren. He will be greatly missed.

  20. The isotopic composition of ore lead of the Creede mining district and vicinity, San Juan Mountains, Colorado: Text of a talk presented at the San Juan Mountains symposium to honor Thomas A. Steven; Rocky Mountain Section meeting of the Geological Society of America, May 2, 1987, Boulder, Colorado

    USGS Publications Warehouse

    Foley, N.K.; Barton, P.B.; Bethke, P.M.; Doe, B.R.

    1988-01-01

    Recent work allows us to extend the results of Doe et al. and to consider alternative processes to explain the widespread homogeneity and radiogenic nature of the ore lead: 1) David Matty (pers. commun., 1986) has shown that some minor volcanic units in the area have unusually radiogneic lead values; magmas comparable in composition to the units are a possible, though improbable, source of the ore lead. 2) The uniformity of the isotopic values of galenas may have resulted from homogenization during an extensive potassium-metasomatic event that predated the ores; this possibility is being tested in an on-going study of feldspars from metasomatized and unmetasomatized rocks. 3) Recent regional studies suggest the possibility of a prevolcanic, NNW-trending graben system filled by clastic sediments derived from the Precambrian basement, a process that would have an homogenizing effect on the lead isotopes. This interpretation implies importation, deep within the Creede hydrologic system, of fluids from remote sources. These alternatives show that the Pbisotope systematics may have a profound impact on the interpretation of the Creede hydrothermal system, and that further study is warranted.

  1. Filling constraints for spin-orbit coupled insulators in symmorphic and nonsymmorphic crystals.

    PubMed

    Watanabe, Haruki; Po, Hoi Chun; Vishwanath, Ashvin; Zaletel, Michael

    2015-11-24

    We determine conditions on the filling of electrons in a crystalline lattice to obtain the equivalent of a band insulator--a gapped insulator with neither symmetry breaking nor fractionalized excitations. We allow for strong interactions, which precludes a free particle description. Previous approaches that extend the Lieb-Schultz-Mattis argument invoked spin conservation in an essential way and cannot be applied to the physically interesting case of spin-orbit coupled systems. Here we introduce two approaches: The first one is an entanglement-based scheme, and the second one studies the system on an appropriate flat "Bieberbach" manifold to obtain the filling conditions for all 230 space groups. These approaches assume only time reversal rather than spin rotation invariance. The results depend crucially on whether the crystal symmetry is symmorphic. Our results clarify when one may infer the existence of an exotic ground state based on the absence of order, and we point out applications to experimentally realized materials. Extensions to new situations involving purely spin models are also mentioned. PMID:26604304

  2. Do negative affect characteristics and subjective memory concerns increase risk for late life anxiety?

    PubMed

    Wilkes, Chelsey M; Wilson, Helen W; Woodard, John L; Calamari, John E

    2013-08-01

    To better understand the development and exacerbation of late-life anxiety, we tested a risk model positing that trait negative affect (NA) characteristics would interact with cognitive functioning, thereby increasing some older adults' risk for increased anxiety symptoms. The moderator-mediator model consisted of measures of NA, cognitive functioning, and their interaction, as predictors of later Hamilton Anxiety Rating Scale scores (HARS) via a mediational process, subjective memory concerns (SMCs). Older adults (aged 65-years and over; M(age)=76.7 years, SD=6.90 years) completed evaluations four times over approximately 18 months. A latent growth curve model including Anxiety Sensitivity Index total score (ASI), Mattis Dementia Rating Scale-2 (DRS) total raw score, the ASI×DRS interaction, a SMC measure as mediator, HARS intercept (scores at times 3 and 4), and HARS slope provided good fit. The ASI×DRS-2 interaction at Time 1 predicted HARS slope score (β=-.34, p<.05). When ASI score was high, stronger cognitive functioning was associated with fewer anxiety symptoms. The indirect effect of ASI score predicting HARS score 18-months later through the SMC mediator was statistically significant (β=.08, p<.05). Results suggest that the cognitive functioning changes associated with aging might contribute to the development of anxiety symptoms in older adults with specific NA traits. Implications for predicting and preventing late life anxiety disorders are discussed.

  3. Development and testing of Band 10 receivers for the ALMA project

    NASA Astrophysics Data System (ADS)

    Uzawa, Y.; Fujii, Y.; Gonzalez, A.; Kaneko, K.; Kroug, M.; Kojima, T.; Kuroiwa, K.; Miyachi, A.; Saito, S.; Makise, K.; Wang, Z.; Asayama, S.

    2013-11-01

    The production model of a dual polarization heterodyne receiver for the Atacama Large Millimeter/submillimteter Array (ALMA) telescope has been developed to operate in the 787-950 GHz frequency band. The receiver uses two double sideband (DSB) waveguide mixers with Nb/AlOx/Nb tunnel junctions and NbTiN/SiO2/Al microstrip tuning circuits on quartz substrate. A terahertz time domain spectrometer was used to characterize our NbTiN film for the tuning circuit design, which revealed that the complex conductivity of the film is described by the Mattis-Bardeen theory including a finite scattering time of 15 fs and a superconducting gap with a gap ratio 2Δ/kBTC ∼ 4.0. Tens of these receivers (out of the total production number of 73) have been successfully produced, and their performance is well within the stringent ALMA requirements. The best achieved DSB receiver noise temperature is 125 K, corresponding to about 3hf/kB for 4 K operation. One of Band 10 receivers has successfully been installed in the ALMA antenna for a test observation.

  4. Expectations from preceding prosody influence segmentation in online sentence processing

    PubMed Central

    Brown, Meredith; Salverda, Anne Pier; Dilley, Laura C.; Tanenhaus, Michael K.

    2013-01-01

    Previous work examining prosodic cues in online spoken-word recognition has focused primarily on local cues to word identity. However, recent studies have suggested that utterance-level prosodic patterns can also influence the interpretation of subsequent sequences of lexically ambiguous syllables (Dilley, Mattys, & Vinke, Journal of Memory and Language, 63:274–294, 2010; Dilley & McAuley, Journal of Memory and Language, 59:294–311, 2008). To test the hypothesis that these distal prosody effects are based on expectations about the organization of upcoming material, we conducted a visual-world experiment. We examined fixations to competing alternatives such as pan and panda upon hearing the target word panda in utterances in which the acoustic properties of the preceding sentence material had been manipulated. The proportions of fixations to the monosyllabic competitor were higher beginning 200 ms after target word onset when the preceding prosody supported a prosodic constituent boundary following pan-, rather than following panda. These findings support the hypothesis that expectations based on perceived prosodic patterns in the distal context influence lexical segmentation and word recognition. PMID:21968925

  5. Broken Symmetries and Gapless Excitations of SU(N) Antiferromagnets Investigated With Variational Wavefunctions

    NASA Astrophysics Data System (ADS)

    Paramekanti, Arun; Marston, Brad

    2005-03-01

    We use Gutzwiller-projected wavefunctions to investigate variationally the phase diagrams of SU(N) quantum antiferromagnets in the self-conjugate representation. The method is first tested against the known phase diagram of a one-dimensional SU(4) bilinear-biquadratic spin chain which has a quantum-critical point separating a dimerized phase from a phase with spontaneously broken charge-conjugation symmetryootnotetextI. Affleck et al., Nucl. Phys. B 366, 467 (1991).. In the case of two-dimensional SU(N) antiferromagnets, recent analyticalootnotetextM. Hermele et al., cond-mat/0404751http://arxiv.org/abs/cond-mat/0404751. and numericalootnotetextF. F. Assaad, cond-mat/0406074http://arxiv.org/abs/cond-mat/0406074. work suggests the existence of a gapless spin-liquid phase with no broken symmetries. Such a phase would be consistent with a recent generalization of the Lieb-Schultz-Mattis theoremootnotetextM. B. Hastings, Phys. Rev. B69, 104431 (2004); cond-mat/0411094http://arxiv.org/abs/cond-mat/0411094. to more than one spatial dimension. We examine the stability of the π-flux phase against tendencies to spin-order, crystallize into various valence-bond solids, or break charge-conjugation symmetry.

  6. Spectral Gaps of Quantum Hall Systems with Interactions

    NASA Astrophysics Data System (ADS)

    Koma, Tohru

    2000-04-01

    A two-dimensional quantum Hall system without disorder for a wide class of interactions including any two-body interaction with finite range is studied by using the Lieb-Schultz-Mattis method [ Ann. Phys. (N.Y.) 16:407 (1961)]. The model is defined on an infinitely long strip with a fixed, large width, and the Hilbert space is restricted to the lowest ( n max+1) Landau levels with a large integer n max. We prove that, for a noninteger filling ν of the Landau levels, either (i) there is a symmetry breaking at zero temperature or (ii) there is only one infinite-volume ground state with a gapless excitation. We also prove the following two theorems: (a) If a pure infinite-volume ground state has a nonzero excitation gap for a noninteger filling ν, then a translational symmetry breaking occurs at zero temperature. (b) Suppose that there is no non-translationally invariant infinite-volume ground state. Then, if a pure infinite-volume ground state has a nonzero excitation gap, the filling factor ν must be equal to a rational number. Here the ground state is allowed to have a periodic structure which is a consequence of the translational symmetry breaking. We also discuss the relation between our results and the quantized Hall conductance, and phenomenologically explain why odd denominators of filling fractions ν giving the quantized Hall conductance are favored exclusively.

  7. The scaling limit of the energy correlations in non-integrable Ising models

    NASA Astrophysics Data System (ADS)

    Giuliani, Alessandro; Greenblatt, Rafael L.; Mastropietro, Vieri

    2012-09-01

    We obtain an explicit expression for the multipoint energy correlations of a non-solvable two-dimensional Ising models with nearest neighbor ferromagnetic interactions plus a weak finite range interaction of strength λ, in a scaling limit in which we send the lattice spacing to zero and the temperature to the critical one. Our analysis is based on an exact mapping of the model into an interacting lattice fermionic theory, which generalizes the one originally used by Schultz, Mattis, and Lieb for the nearest neighbor Ising model. The interacting model is then analyzed by a multiscale method first proposed by Pinson and Spencer. If the lattice spacing is finite, then the correlations cannot be computed in closed form: rather, they are expressed in terms of infinite, convergent, power series in λ. In the scaling limit, these infinite expansions radically simplify and reduce to the limiting energy correlations of the integrable Ising model, up to a finite renormalization of the parameters. Explicit bounds on the speed of convergence to the scaling limit are derived.

  8. Quantum phase transitions of spin chiral nanotubes

    NASA Astrophysics Data System (ADS)

    Matsumoto, Munehisa; Sakai, Toru; Sato, Masahiro; Takayama, Hajime; Todo, Synge

    2005-11-01

    Recently many interesting magnetic nanostructures have been fabricated and much attention is arising on the rich magnetic properties that originate in the quantum effects eminent in the nanoscale world. One of the peculiar aspects of the quantum effects is the spin excitation gap. In the spin- 1/2 low-dimensional systems, the spin gap often appears when the lattice dimerization or the frustration in the spin-spin interaction are introduced. In the present study, we investigate the ground-state property of the spin- 1/2 antiferromagnetic spin chiral nanotubes with the spatial modulation in the spin-spin interaction. The ground-state phase diagrams of them are determined by observing the behavior of the expectation value of the Lieb-Schultz-Mattis slow-twist operator calculated by the quantum Monte Carlo method with the continuous-time loop algorithm. We discuss the relation between the characteristic of the topology of the phase diagram and the chiral vector of the nanotubes.

  9. Generalization of Luttinger's Theorem for Fermionic Ladder Systems

    NASA Astrophysics Data System (ADS)

    Gagliardini, P.; Haas, S.; Rice, T. M.; Sigrist, M.

    1998-03-01

    Recently Yamanaka et al.(M. Yamanaka, M. Oshikawa, and I. Affleck, PRL 79), 1110 (1997). adapted the Lieb-Schultz-Mattis theorem to obtain a non-perturbative generalization of Luttinger's theorem for 1-dim. fermionic systems. Their method can be extended to ladder systems. The key quantity which enters in a Hubbard or t-J model is the sum of the electron occupation numbers on a rung. At half-filling, this leads at once to a proof that undoped Heisenberg ladders have gapless excitations when the number of legs is odd. Upon doping, the Fermi wavevectors of individual channels are not conserved under interaction, but their sum is. This result does not require a Fermi surface in each channel and is consistent with the recently proposed assignment of 1 el. per rung to gapped insulating even-parity channels, and 1-δ els. to a Luttinger liquid in the odd-parity channel in a lightly doped 3-leg ladder (δ: hole doping). The crossover to 2 dim. occurs in the limit of a large number of legs, and it is the area enclosed by the Fermi surface which enters, consistent with Luttinger's theorem for the case of Landau Fermi liquids.

  10. Parallel retrieval of correlated patterns: from Hopfield networks to Boltzmann machines.

    PubMed

    Agliari, Elena; Barra, Adriano; De Antoni, Andrea; Galluzzi, Andrea

    2013-02-01

    In this work, we first revise some extensions of the standard Hopfield model in the low storage limit, namely the correlated attractor case and the multitasking case recently introduced by the authors. The former case is based on a modification of the Hebbian prescription, which induces a coupling between consecutive patterns and this effect is tuned by a parameter a. In the latter case, dilution is introduced in pattern entries, in such a way that a fraction d of them is blank. Then, we merge these two extensions to obtain a system able to retrieve several patterns in parallel and the quality of retrieval, encoded by the set of Mattis magnetizations {m(μ)}, is reminiscent of the correlation among patterns. By tuning the parameters d and a, qualitatively different outputs emerge, ranging from highly hierarchical to symmetric. The investigations are accomplished by means of both numerical simulations and statistical mechanics analysis, properly adapting a novel technique originally developed for spin glasses, i.e. the Hamilton-Jacobi interpolation, with excellent agreement. Finally, we show the thermodynamical equivalence of this associative network with a (restricted) Boltzmann machine and study its stochastic dynamics to obtain even a dynamical picture, perfectly consistent with the static scenario earlier discussed. PMID:23246601

  11. Assessing allele-specific expression across multiple tissues from RNA-seq read data

    PubMed Central

    Pirinen, Matti; Lappalainen, Tuuli; Zaitlen, Noah A.; Dermitzakis, Emmanouil T.; Donnelly, Peter; McCarthy, Mark I.; Rivas, Manuel A.

    2015-01-01

    Motivation: RNA sequencing enables allele-specific expression (ASE) studies that complement standard genotype expression studies for common variants and, importantly, also allow measuring the regulatory impact of rare variants. The Genotype-Tissue Expression (GTEx) project is collecting RNA-seq data on multiple tissues of a same set of individuals and novel methods are required for the analysis of these data. Results: We present a statistical method to compare different patterns of ASE across tissues and to classify genetic variants according to their impact on the tissue-wide expression profile. We focus on strong ASE effects that we are expecting to see for protein-truncating variants, but our method can also be adjusted for other types of ASE effects. We illustrate the method with a real data example on a tissue-wide expression profile of a variant causal for lipoid proteinosis, and with a simulation study to assess our method more generally. Availability and implementation: http://www.well.ox.ac.uk/~rivas/mamba/. R-sources and data examples http://www.iki.fi/mpirinen/ Contact: matti.pirinen@helsinki.fi or rivas@well.ox.ac.uk Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25819081

  12. Minimal Clinically Important Difference on Parkinson's Disease Sleep Scale 2nd Version.

    PubMed

    Horváth, Krisztina; Aschermann, Zsuzsanna; Ács, Péter; Deli, Gabriella; Janszky, József; Komoly, Sámuel; Karádi, Kázmér; Kovács, Márton; Makkos, Attila; Faludi, Béla; Kovács, Norbert

    2015-01-01

    Background and Aims. The aim of the present study was to determine the estimates of minimal clinically important difference for Parkinson's Disease Sleep Scale 2nd version (PDSS-2) total score and dimensions. Methods. The subject population consisted of 413 PD patients. At baseline, MDS-UPDRS, Hoehn-Yahr Scale, Mattis Dementia Rating Scale, and PDSS-2 were assessed. Nine months later the PDSS-2 was reevaluated with the Patient-Reported Global Impression Improvement Scale. Both anchor-based techniques (within patients' score change method and sensitivity- and specificity-based method by receiver operating characteristic analysis) and distribution-based approaches (effect size calculations) were utilized to determine the magnitude of minimal clinically important difference. Results. According to our results, any improvements larger than -3.44 points or worsening larger than 2.07 points can represent clinically important changes for the patients. These thresholds have the effect size of 0.21 and -0.21, respectively. Conclusions. Minimal clinically important differences are the smallest change of scores that are subjectively meaningful to patients. Studies using the PDSS-2 as outcome measure should utilize the threshold of -3.44 points for detecting improvement or the threshold of 2.07 points for observing worsening.

  13. metaCCA: summary statistics-based multivariate meta-analysis of genome-wide association studies using canonical correlation analysis

    PubMed Central

    Cichonska, Anna; Rousu, Juho; Marttinen, Pekka; Kangas, Antti J.; Soininen, Pasi; Lehtimäki, Terho; Raitakari, Olli T.; Järvelin, Marjo-Riitta; Salomaa, Veikko; Ala-Korpela, Mika; Ripatti, Samuli; Pirinen, Matti

    2016-01-01

    Motivation: A dominant approach to genetic association studies is to perform univariate tests between genotype-phenotype pairs. However, analyzing related traits together increases statistical power, and certain complex associations become detectable only when several variants are tested jointly. Currently, modest sample sizes of individual cohorts, and restricted availability of individual-level genotype-phenotype data across the cohorts limit conducting multivariate tests. Results: We introduce metaCCA, a computational framework for summary statistics-based analysis of a single or multiple studies that allows multivariate representation of both genotype and phenotype. It extends the statistical technique of canonical correlation analysis to the setting where original individual-level records are not available, and employs a covariance shrinkage algorithm to achieve robustness. Multivariate meta-analysis of two Finnish studies of nuclear magnetic resonance metabolomics by metaCCA, using standard univariate output from the program SNPTEST, shows an excellent agreement with the pooled individual-level analysis of original data. Motivated by strong multivariate signals in the lipid genes tested, we envision that multivariate association testing using metaCCA has a great potential to provide novel insights from already published summary statistics from high-throughput phenotyping technologies. Availability and implementation: Code is available at https://github.com/aalto-ics-kepaco Contacts: anna.cichonska@helsinki.fi or matti.pirinen@helsinki.fi Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27153689

  14. Filling constraints for spin-orbit coupled insulators in symmorphic and nonsymmorphic crystals

    PubMed Central

    Watanabe, Haruki; Po, Hoi Chun; Vishwanath, Ashvin; Zaletel, Michael

    2015-01-01

    We determine conditions on the filling of electrons in a crystalline lattice to obtain the equivalent of a band insulator—a gapped insulator with neither symmetry breaking nor fractionalized excitations. We allow for strong interactions, which precludes a free particle description. Previous approaches that extend the Lieb–Schultz–Mattis argument invoked spin conservation in an essential way and cannot be applied to the physically interesting case of spin-orbit coupled systems. Here we introduce two approaches: The first one is an entanglement-based scheme, and the second one studies the system on an appropriate flat “Bieberbach” manifold to obtain the filling conditions for all 230 space groups. These approaches assume only time reversal rather than spin rotation invariance. The results depend crucially on whether the crystal symmetry is symmorphic. Our results clarify when one may infer the existence of an exotic ground state based on the absence of order, and we point out applications to experimentally realized materials. Extensions to new situations involving purely spin models are also mentioned. PMID:26604304

  15. Sign structure and ground-state properties for a spin-S t-J chain

    NASA Astrophysics Data System (ADS)

    Wang, Qing-Rui; Ye, Peng

    2014-07-01

    The antiferromagnetic Heisenberg spin chain of odd spin S is in the Haldane phase with several defining physical properties, such as thermodynamical ground-state degeneracy, symmetry-protected edge states, and nonzero string order parameter. If nonzero hole concentration δ and hole hopping energy t are considered, the spin chain is replaced by a spin-S t-J chain. The motivation of this paper is to generalize the discussions of the Haldane phase to the doped spin chain. The first result of this paper is that, for the model considered here, the Z2 sign structure in the usual Ising basis can be totally removed by two consecutive unitary transformations consisting of a spatially local one and a nonlocal one. Direct from the sign structure, the second result of this paper is that the Marshall theorem and the Lieb-Mattis theorem for pure spin systems are generalized to the t-J chain for arbitrary S and δ. A corollary of the theorem provides us with the ground-state degeneracy in the thermodynamic limit. The third result of this paper is about the phase diagram. We show that the defining properties of the Haldane phase survive in the small t /J limit. The large t /J phase supports a gapped spin sector with similar properties (ground-state degeneracy, edge state, and string order parameter) of the Haldane chain, although the charge sector is gapless.

  16. Summary Report of Cable Aging and Performance Data for Fiscal Year 2014.

    SciTech Connect

    Celina, Mathias Christopher; Celina, Mathias Christopher; Redline, Erica Marie; Redline, Erica Marie; Bernstein, Robert; Bernstein, Robert; Quintana, Adam; Quintana, Adam; Giron, Nicholas Henry; Giron, Nicholas Henry; White II, Gregory Von; White II, Gregory Von

    2014-09-01

    As part of the Light Water Reactor Sustainability Program, science - based engineering approaches were employed to address cable degradation behavior under a range of exposure environments. Experiments were conducted with the goal to provide best guidance for aged material states, remaining life and expected performance under specific conditions for a range of cable materials. Generic engineering tests , which focus on rapid accelerated aging and tensile elongation , were combined with complementar y methods from polymer degradation science. Sandia's approach, building on previous years' efforts, enabled the generation of some of the necessary data supporting the development of improved lifetime predictions models, which incorporate known material b ehaviors and feedback from field - returned 'aged' cable materials. Oxidation rate measurements have provided access to material behavior under low dose rate thermal conditions, where slow degradation is not apparent in mechanical property changes. Such da ta have shown aging kinetics consistent with established radiati on - thermal degradation models. ACKNOWLEDGEMENTS We gratefully acknowledge ongoing technical support at the LICA facility and extensive sample handling provided by Maryla Wasiolek and Don Hans on. Sam Durbin and Patrick Mattie are recognized for valuable guidance throughout the year and assistance in the preparation of the final report. Doug Brunson is appreciated for sample analysis, compilation and plotting of experimental data.

  17. PREFACE: First International Congress of the International Association of Inverse Problems (IPIA): Applied Inverse Problems 2007: Theoretical and Computational Aspects

    NASA Astrophysics Data System (ADS)

    Uhlmann, Gunther

    2008-07-01

    , Finland), Masahiro Yamamoto (University of Tokyo, Japan), Gunther Uhlmann (University of Washington) and Jun Zou (Chinese University of Hong Kong). IPIA is a recently formed organization that intends to promote the field of inverse problem at all levels. See http://www.inverse-problems.net/. IPIA awarded the first Calderón prize at the opening of the conference to Matti Lassas (see first article in the Proceedings). There was also a general meeting of IPIA during the workshop. This was probably the largest conference ever on IP with 350 registered participants. The program consisted of 18 invited speakers and the Calderón Prize Lecture given by Matti Lassas. Another integral part of the program was the more than 60 mini-symposia that covered a broad spectrum of the theory and applications of inverse problems, focusing on recent developments in medical imaging, seismic exploration, remote sensing, industrial applications, numerical and regularization methods in inverse problems. Another important related topic was image processing in particular the advances which have allowed for significant enhancement of widely used imaging techniques. For more details on the program see the web page: http://www.pims.math.ca/science/2007/07aip. These proceedings reflect the broad spectrum of topics covered in AIP 2007. The conference and these proceedings would not have happened without the contributions of many people. I thank all my fellow organizers, the invited speakers, the speakers and organizers of mini-symposia for making this an exciting and vibrant event. I also thank PIMS, NSF and MITACS for their generous financial support. I take this opportunity to thank the PIMS staff, particularly Ken Leung, for making the local arrangements. Also thanks are due to Stephen McDowall for his help in preparing the schedule of the conference and Xiaosheng Li for the help in preparing these proceedings. I also would like to thank the contributors of this volume and the referees. Finally

  18. PREFACE: First International Congress of the International Association of Inverse Problems (IPIA): Applied Inverse Problems 2007: Theoretical and Computational Aspects

    NASA Astrophysics Data System (ADS)

    Uhlmann, Gunther

    2008-07-01

    , Finland), Masahiro Yamamoto (University of Tokyo, Japan), Gunther Uhlmann (University of Washington) and Jun Zou (Chinese University of Hong Kong). IPIA is a recently formed organization that intends to promote the field of inverse problem at all levels. See http://www.inverse-problems.net/. IPIA awarded the first Calderón prize at the opening of the conference to Matti Lassas (see first article in the Proceedings). There was also a general meeting of IPIA during the workshop. This was probably the largest conference ever on IP with 350 registered participants. The program consisted of 18 invited speakers and the Calderón Prize Lecture given by Matti Lassas. Another integral part of the program was the more than 60 mini-symposia that covered a broad spectrum of the theory and applications of inverse problems, focusing on recent developments in medical imaging, seismic exploration, remote sensing, industrial applications, numerical and regularization methods in inverse problems. Another important related topic was image processing in particular the advances which have allowed for significant enhancement of widely used imaging techniques. For more details on the program see the web page: http://www.pims.math.ca/science/2007/07aip. These proceedings reflect the broad spectrum of topics covered in AIP 2007. The conference and these proceedings would not have happened without the contributions of many people. I thank all my fellow organizers, the invited speakers, the speakers and organizers of mini-symposia for making this an exciting and vibrant event. I also thank PIMS, NSF and MITACS for their generous financial support. I take this opportunity to thank the PIMS staff, particularly Ken Leung, for making the local arrangements. Also thanks are due to Stephen McDowall for his help in preparing the schedule of the conference and Xiaosheng Li for the help in preparing these proceedings. I also would like to thank the contributors of this volume and the referees. Finally

  19. The Structure and Molecular Parameters of Camphene Determined by Fourier Transform Microwave Spectroscopy and Quantum Chemical Calculations

    NASA Astrophysics Data System (ADS)

    Neeman, Elias M.; Dréan, Pascal; Huet, T. R.

    2016-06-01

    The emission of volatile organic compounds, from plants has strong revelance for plant physiology, plant ecology and atmospheric chemistry. Camphene (C10H16) is a bicyclic monoterpene which is emitted in the atmosphere by biogenic sources. The structure of the unique stable conformer was optimized using density functional theory and ab initio calculations. The rotational spectrum of camphene was recorded in a supersonic jet expansion with a Fourier transform microwave spectrometer over the range 2-20 GHz. Signals from the parent species and from the ten 13C isotopomers were observed in natural abundance. The rotational and centrifugal distortion parameters were fitted to a Watson's Hamiltonian in the A-reduction. A magnetic hyperfine structure associated with the pairs of hydrogen nuclei in the methylene groups was observed and modeled.The rotational constants coupled to the equilibrium structure calculations were used to determine the r_0 and the r_m(1) gas-phase geometries of the carbon skeleton. The present work provides the first spectroscopic characterization of camphene in the gas phase and these results are also relevant for ozonolysis kinetics study through Criegee intermediates. R. Baraldi, F. Rapparini, O. Facini, D. Spano and P. Duce, Journal of Mediterranean Ecology, Vol.6, No.1, (2005). A. Bracho-Nunez, N. M. Knothe, S. Welter, M. Staudt, W. R. Costa, M. A. R. Liberato, M. T. F. Piedade, and J. Kesselmeier Biogeosciences, 10, 5855-5873, (2013). Minna Kivimäenpää, Narantsetseg Magsarjav, Rajendra Ghimire, Juha-Matti Markkanen, Juha Heijari, Martti Vuorinen and Jarmo K. Holopainen, Atmospheric Environment, 60, 477-485, (2012). R.C. de M. Oliveira and G. F. Bauerfeldt, J. Phys. Chem. A, 119 2802-2812 (2015)

  20. Emergence of massless Dirac quasiparticles in correlated hydrogenated graphene with broken sublattice symmetry

    NASA Astrophysics Data System (ADS)

    Seki, Kazuhiro; Shirakawa, Tomonori; Zhang, Qinfang; Li, Tao; Yunoki, Seiji

    2016-04-01

    Using the variational cluster approximation (VCA) and the cluster perturbation theory, we study the finite-temperature phase diagram of a half-depleted periodic Anderson model on the honeycomb lattice at half-filling for a model of graphone, i.e., single-side hydrogenated graphene. The ground state of this model is found to be ferromagnetic (FM) semimetal. The origin of this FM state is attributed to the instability of a flat band located at the Fermi energy in the noninteracting limit and is smoothly connected to the Lieb-Mattis-type ferromagnetism. The spin-wave dispersion in the FM state is linear in momentum at zero temperature but becomes quadratic at finite temperatures, implying that the FM state is fragile against thermal fluctuations. Indeed, our VCA calculations find that the paramagnetic (PM) state dominates the finite-temperature phase diagram. More surprisingly, we find that massless Dirac quasiparticles with the linear energy dispersion emerge at the Fermi energy upon introducing the electron correlation U at the impurity sites in the PM phase. The Dirac Fermi velocity is found to be highly correlated to the quasiparticle weight of the emergent massless Dirac quasiparticles at the Fermi energy and monotonically increases with U . These unexpected massless Dirac quasiparticles are also examined with the Hubbard-I approximation and the origin is discussed in terms of the spectral weight redistribution involving a large energy scale of U . Considering an effective quasiparticle Hamiltonian which reproduces the single-particle excitations obtained by the Hubbard-I approximation, we argue that the massless Dirac quasiparticles are protected by the electron correlation. Our finding therefore provides a unique example of the emergence of massless Dirac quasiparticles due to dynamical electron correlations without breaking any spatial symmetry. The experimental implications of our results for graphone as well as a graphene sheet on transition-metal substrates

  1. Parkinson's disease-cognitive rating scale: psychometrics for mild cognitive impairment.

    PubMed

    Fernández de Bobadilla, Ramón; Pagonabarraga, Javier; Martínez-Horta, Saül; Pascual-Sedano, Berta; Campolongo, Antonia; Kulisevsky, Jaime

    2013-09-01

    Lack of validated data on cutoff scores for mild cognitive impairment (MCI) and sensitivity to change in predementia stages of Parkinson's disease (PD) limit the utility of instruments measuring global cognition as screening and outcome measures in therapeutic trials. Investigators who were blinded to PD-Cognitive Rating Scale (PD-CRS) scores classified a cohort of prospectively recruited, nondemented patients into a PD with normal cognition (PD-NC) group and a PD with MCI (PD-MCI) group using Clinical Dementia Rating (CDR) and the Mattis Dementia Rating Scale-2 (MDRS-2). The discriminative power of the PD-CRS for PD-MCI was examined in a representative sample of 234 patients (145 in the PD-NC group; 89 in the PD-MCI group) and in a control group of 98 healthy individuals. Sensitivity to change in the PD-CRS score (the minimal clinically important difference was examined with the Clinical Global Impression of Change scale and was calculated with a combination of distribution-based and anchor-based approaches) was explored in a 6-month observational multicenter trial involving a subset of 120 patients (PD-NC, 63; PD-MCI, 57). Regression analysis demonstrated that PD-CRS total scores (P < 0.001) and age (P = 0.01) independently differentiated PD-NC from PD-MCI. Area under the receiver operating characteristic curve (AUC) analysis (AUC, 0.85; 95% confidence interval, 0.80-0.90) indicated that a score ≤ 81 of 134 was the optimal cutoff point on the total score for the PD-CRS (sensitivity, 79%; specificity, 80%; positive predictive value, 59%; negative predictive value, 91%). A range of change from 10 to 13 points on the PD-CRS total score was indicative of clinically significant change. These findings suggest that the PD-CRS is a useful tool to identify PD-MCI and to track cognitive changes in nondemented patients with PD.

  2. Application of Bogolyubov's theory of weakly nonideal Bose gases to the A+A, A+B, B+B reaction-diffusion system.

    PubMed

    Konkoli, Zoran

    2004-01-01

    Theoretical methods for dealing with diffusion-controlled reactions inevitably rely on some kind of approximation, and to find the one that works on a particular problem is not always easy. Here the approximation used by Bogolyubov to study a weakly nonideal Bose gas, referred to as the weakly nonideal Bose gas approximation (WBGA), is applied in the analysis of three reaction-diffusion models: (i) A+A-->Ø, (ii) A+B-->Ø, and (iii) A+A,B+B,A+B-->Ø (the ABBA model). Two types of WBGA are considered, the simpler WBGA-I and the more complicated WBGA-II. All models are defined on the lattice to facilitate comparison with computer experiment (simulation). It is found that the WBGA describes the A+B reaction well, it reproduces the correct d/4 density decay exponent. However, it fails in the case of the A+A reaction and the ABBA model. (To cure the deficiency of WBGA in dealing with the A+A model, a hybrid of the WBGA and Kirkwood superposition approximations is suggested.) It is shown that the WBGA-I is identical to the dressed-tree calculation suggested by Lee [J. Phys. A 27, 2633 (1994)], and that the dressed-tree calculation does not lead to the d/2 density decay exponent when applied to the A+A reaction, as normally believed, but it predicts the d/4 decay exponent. Last, the usage of the small n(0) approximation suggested by Mattis and Glasser [Rev. Mod. Phys. 70, 979 (1998)] is questioned if used beyond the A+B reaction-diffusion model. PMID:14995603

  3. Digital geologic map of Fawnskin 7.5' quadrangle, San Bernardino County, California

    USGS Publications Warehouse

    Miller, F.K.; Matti, J.C.; Brown, H.J.; Powell, R.E.

    2001-01-01

    a. This Readme; includes in Appendix I, data contained in fskn_met.txt b. The same graphic as plotted in 2 above. (Test plots from this .pdf do not produce 1:24,000-scale maps. Adobe Acrobat page-size settings control map scale.) This release includes features not found in most other digital geologic maps, in that all polygons, lines, and points in the coverage are encoded with detailed, comprehensive geologic data contained in six INFO data tables (.rel). (See Matti and others, 1998a, 1998b, and 1998c, for information on how the encoding may be accessed and utilized.) No paper map is included in the Open-File Report, but a PostScript plot file containing an image of the geologic map sheet, topographic base, Correlation of Map Units (CMU), and detailed Description of Map Units (DMU) is. The Correlation of Map Units and Description of Map Units are in the editorial format of USGS Miscellaneous Investigations Series maps (I-maps) but have not been edited to comply with I-map standards. Within the geologic map data package, map units are identified by such standard geologic-map criteria as formation name, age, and lithology. Even though this is an author-prepared report, every attempt has been made to closely adhere to the stratigraphic nomenclature of the U.S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the PostScript file (2 above). If roads in some areas, especially roads that parallel topographic contours, do not show well on plots of the geologic map, we recommend use of the USGS Fawnskin 7.5' topographic quadrangle in conjunction with the geologic map.

  4. Geologic map of the Lakeview 7.5' quadrangle, Riverside County, California

    USGS Publications Warehouse

    Morton, Douglas M.; Matti, Jonathan C.

    2001-01-01

    This Open-File Report contains a digital geologic map and map database of the Lakeview 7.5' quadrangle, Riverside County, California, that includes: 1. ARC/INFO (Environmental Systems Research Institute) version 7.2.1 double-precision coverages of the various elements of the geologic map 2. A Postscript file to plot the geologic map on a topographic base, and containing a Correlation of Map Units diagram and a Description of Map Units 3. Portable Document Format (.pdf) files of: a. This Readme; includes, in Appendix I, data contained in lkvw_met.txt b. The same graphic as plotted in 2 above. (Test plots from this .pdf do not produce 1:24,000-scale maps. Adobe Acrobat page size settings control map scale.) This release includes features not found in most other digital geologic maps, in that all polygons, lines, and points in the coverage are encoded with detailed, comprehensive, contained in five INFO data tables (.rel) (see Matti and others, 1998a, 1998b, and 1998c for information on how the encoding may be accessed and utilized). No paper map is included in this report, but a PostScript plot file containing an image of the geologic map sheet, topographic base, Correlation of Map Units (CMU), and detailed Description of Map Units (DMU) is. Within the geologic map data package, map units are identified by standard geologic map criteria such as formation name, age, and lithology. Even though this is an author-prepared report, every attempt has been made to closely adhere to the stratigraphic nomenclature of the U. S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the postscript file (2 above). If roads in some areas, especially roads that parallel topographic contours, do not show well on plots of the geologic map, we recommend use of the USGS Lakeview 7.5' topographic quadrangle in conjunction with the geologic map.

  5. The Movement Disorders Society criteria for the diagnosis of Parkinson's disease dementia: their usefulness and limitations in elderly patients.

    PubMed

    Kiesmann, Michèle; Chanson, Jean-Baptiste; Godet, Julien; Vogel, Thomas; Schweiger, Laetitia; Chayer, Saïd; Kaltenbach, Georges

    2013-10-01

    The aim of this study was to assess the performance of the Movement Disorders Society (MDS) criteria for the diagnosis of Parkinson's disease dementia (PDD) in the elderly, and also to evaluate the relevance of applying other tests in this patient population. The MDS criteria include a first short part in checklist form, and a second part which is used as a basis for reference and consists of an in-depth neuropsychological examination. Forty consecutive PD patients presenting with cognitive complaints were enrolled. An assessment was made of the performances of the MDS checklist compared with the MDS exhaustive cognitive examination which was used as a basis for reference, and with other cognitive tests including the Mattis Dementia Rating Scale (MDRS), the French version of the Grober and Buschke test, the verbal fluency test, the Rey-Osterreith complex figure and the paced auditory serial addition test. Out of a total of 40 PD subjects (mean age: 80.5 ± 4.9 years), 20 were diagnosed with PDD according to the checklist and 31 on the basis of the exhaustive examination, i.e. with 11 more patients diagnosed via the latter. The sensitivity of the checklist for the diagnosis of PDD was 0.64, with a specificity of 1.00. The use of the MDRS for PDD diagnosis with a cut-off at ≤ 120 showed a sensitivity of 0.80 and a specificity of 1.00, while at ≤ 132 it displayed a sensitivity of 1.00 and a specificity of 0.444. The specificity of the checklist for the diagnosis of PDD in the elderly was confirmed, but it was lacking in sensitivity. It was also found that the MDRS could be helpful in the diagnosis and screening of PDD. PMID:23835635

  6. Effectiveness of cognitive training for Chinese elderly in Hong Kong

    PubMed Central

    Kwok, Timothy; Wong, Anita; Chan, Grace; Shiu, YY; Lam, Ko-Chuen; Young, Daniel; Ho, Daniel WH; Ho, Florence

    2013-01-01

    In Hong Kong, the evidence for cognitive-training programs in fighting against memory complaints is lacking. This study aimed to evaluate the effectiveness of the Active Mind cognitive-training program in improving the cognitive function and quality of life (QoL) for local community-dwelling Chinese older adults. A total of 200 subjects were recruited from 20 different district elderly community centers (DECCs). Centers were randomly assigned into either the intervention group or control group. The intervention group underwent eight 1-hour sessions of cognitive training, while the control group were included in the usual group activities provided by the DECCs. Standardized neuropsychological tests (the Chinese version of Mattis Dementia Rating Scale [CDRS] and the Cantonese version of the Mini-Mental State Examination) and the QoL questionnaire SF12 were used to assess participants’ cognitive function and QoL before and after the trial. A total of 176 subjects completed the study. The intervention group showed greater improvement in the cognitive function measured by total CDRS score (treatment: 12.24 ± 11.57 vs control: 4.37 ± 7.99; P < 0.001) and QoL measured by total SF12 score (treatment: 7.82 ± 13.19 vs control: 3.18 ± 11.61; P = 0.014). Subjects with lower education level were associated with better cognitive response to the cognitive-training program. The current findings indicated that the Active Mind cognitive-training program was effective in improving the cognitive function and QoL for community-dwelling Chinese older adults in Hong Kong. PMID:23440076

  7. Changes in brain volume and cognition in a randomized trial of exercise and social interaction in a community-based sample of non-demented Chinese elders.

    PubMed

    Mortimer, James A; Ding, Ding; Borenstein, Amy R; DeCarli, Charles; Guo, Qihao; Wu, Yougui; Zhao, Qianhua; Chu, Shugang

    2012-01-01

    Physical exercise has been shown to increase brain volume and improve cognition in randomized trials of non-demented elderly. Although greater social engagement was found to reduce dementia risk in observational studies, randomized trials of social interventions have not been reported. A representative sample of 120 elderly from Shanghai, China was randomized to four groups (Tai Chi, Walking, Social Interaction, No Intervention) for 40 weeks. Two MRIs were obtained, one before the intervention period, the other after. A neuropsychological battery was administered at baseline, 20 weeks, and 40 weeks. Comparison of changes in brain volumes in intervention groups with the No Intervention group were assessed by t-tests. Time-intervention group interactions for neuropsychological measures were evaluated with repeated-measures mixed models. Compared to the No Intervention group, significant increases in brain volume were seen in the Tai Chi and Social Intervention groups (p < 0.05). Improvements also were observed in several neuropsychological measures in the Tai Chi group, including the Mattis Dementia Rating Scale score (p = 0.004), the Trailmaking Test A (p = 0.002) and B (p = 0.0002), the Auditory Verbal Learning Test (p = 0.009), and verbal fluency for animals (p = 0.01). The Social Interaction group showed improvement on some, but fewer neuropsychological indices. No differences were observed between the Walking and No Intervention groups. The findings differ from previous clinical trials in showing increases in brain volume and improvements in cognition with a largely non-aerobic exercise (Tai Chi). In addition, intellectual stimulation through social interaction was associated with increases in brain volume as well as with some cognitive improvements.

  8. Study of Potential Sub-Micrometer-Thick Frost Events and Soil Water Content at Gale Crater

    NASA Astrophysics Data System (ADS)

    Martinez, G.; Fischer, E.; Renno, N. O.; De La Torre Juarez, M.; Meslin, P. Y.; Kemppinen, O.; Genzer, M.; Harri, A. M.; Ramos, M.; Borlina, C.; Schröder, S.; Gómez-Elvira, J.

    2014-12-01

    We analyze the highest confidence measurements of relative humidity [1] and ground temperature [2] to identify potential frost events at the surface of Gale Crater during the first 600 sols of the MSL mission. We find that between 4 and 6 am on sols 533, 535, 555, 557, 559 and 560 the ground temperature falls below the calculated frost point. Order-of-magnitude estimate for the thickness of the frost layer indicates that it is of the order of micrometers or less. Additionally, we analyze the relation between water vapor pressure and ground temperature to provide additional constraints on potential frost events and to quantify the exchange of adsorbed water between the surface and the atmosphere. Adsorbed water could be forced into liquid-like state at the of Gale because van der Waals forces between water ice molecules and mineral surfaces reduces the freezing point [3]. This form of liquid water is relevant to habitability because microorganisms could survive in liquid-like adsorbed water [4].References: [1] Harri, Ari-Matti et al., Mars Science Laboratory Relative Humidity Observations - Initial Results (2014), JGR (in press). [2] Martínez, G. M. et al., Surface Energy Budget and Thermal Inertia at Gale Crater: Calculations from Ground-Based Measurements (2014), JGR (in press). [3] Möhlmann, D., The influence of van der Waals forces on the state of water in the shallow subsurface of Mars (2008), Icarus 195 (1), 131-139. [4] Rivkina, E. M. et al., Metabolic activity of permafrost bacteria below the freezing point (2000), Appl. Environ. Microbiol., 66(8), 3230-3233.

  9. Dopamine and the Biology of Creativity: Lessons from Parkinson’s Disease

    PubMed Central

    Lhommée, Eugénie; Batir, Alina; Quesada, Jean-Louis; Ardouin, Claire; Fraix, Valérie; Seigneuret, Eric; Chabardès, Stéphan; Benabid, Alim-Louis; Pollak, Pierre; Krack, Paul

    2014-01-01

    Background: Parkinson’s disease (PD) is characterized by reduced flexibility, conceptualization, and visuo-spatial abilities. Although these are essential to creativity, case studies show emergence of creativity during PD. Knowledge about the role of dopamine in creativity so far only stems from a few case reports. We aim at demonstrating that creativity can be induced by dopaminergic treatments in PD, and tends to disappear after withdrawal of dopamine agonists. Methods: Eleven consecutive creative PD patients were selected from candidates for subthalamic nucleus deep brain stimulation (STN DBS) surgery, and compared to 22 non-creative control PD patients. Motor disability (UPDRS III), cognition (Frontal score, Mattis scale), and behavior (Ardouin scale) were assessed before surgery and 1 year after. Results: Before surgery, whereas cognitive and motor assessments were similar between groups, dopamine agonist (but not levodopa) dosages were higher in creative patients (p = 0.01). The Ardouin scale revealed also a specific psycho-behavioral profile of creative patients which had higher scores for mania (p < 0.001), hobbyism (p = 0.001), nocturnal hyperactivity (p = 0.041), appetitive functioning (p = 0.003), and ON euphoria (p = 0.007) and lower scores for apathy and OFF dysphoria (p = 0.04 for each). Post-operative motor, cognitive, and behavioral scores as dopaminergic treatment dosages were equivalent between groups. Motor improvement allowed for a 68.6% decrease in dopaminergic treatment. Only 1 of the 11 patients remained creative after surgery. Reduction of dopamine agonist was significantly correlated to the decrease in creativity in the whole population of study (Spearman correlation coefficient ρ = 0.47 with confidence index of 95% = 0.16; 0.70, p = 0.0053). Conclusion: Creativity in PD is linked to dopamine agonist therapy, and tends to disappear after STN DBS in parallel to reduction of dopamine agonists

  10. On the instrumental characterization of a 3-λ scanning lidar to monitor industrial flames and its application for retrieving optical and microphysical properties

    NASA Astrophysics Data System (ADS)

    Guerrero-Rascado, Juan Luis; da Costa, Renata; Esteban Bedoya, Andrés; Guardani, Roberto; Alados-Arboledas, Lucas; Efrain Bastidas, Álvaro; Landulfo, Eduardo

    2015-04-01

    The emission of pollutants in megacities and industrial areas can have strong impact, not only from an environmental point of view, but also for human health. Cubatão (23° 53' S, 46° 26' W, 10 m asl) has been one of the most industrialized city in Brazil (located at São Paulo state coast) during the last decades. This work deals with the recent advances made on a 3-λ scanning lidar placed at this industrial region. Special attention has been paid to the characterization of the electronic performance of this lidar system. For this goal, the quality assurance tests, regularly applied in well-established lidar networks such as LALINET [Guerrero-Rascado et al., 2014] and EARLINET [Pappalardo et al. 2014], were applied to the Cubatão scanning lidar in order to improve the knowledge of its performing itself and to design protocols for correcting lidar signal for undesirable instrumental effects. The application of the results derived from these quality assurance tests together with the state-of-the-art methodologies to map the particle optical and microphysical properties inside industrial flares demonstrate the potential of this lidar for the study and measurement of industrial emissions. References: J. L. Guerrero-Rascado, E. Landulfo, J. C. Antuña, H. M. J. Barbosa, B. Barja, A. E. Bastidas, A. E. Bedoya, R. da Costa, R. Estevan, R. N. Forno, D. A. Gouveia, C. Jiménez, E. G. Larroza, F. J. S. Lopes, E. Montilla-Rosero, G. A. Moreira, W. M. Nakaema, D. Nisperuza, L. Otero, J. V. Pallotta, S. Papandrea, E. Pawelko, E. J. Quel, P. Ristori, P. F. Rodrigues, J. Salvador, M. F. Sánchez, and A. Silva, "Towards an instrumental harmonization in the framework of LAINET: dataset of technical specifications", Proceedings of SPIE 2014, vol. 9246, 92460O-1 -- 92460O-14, doi: 10.1117/12.2066873 (2014) G. Pappalardo, A. Amodeo, A. Apituley, A. Comerón, V. Freudenthaler, H. Linné, A. Ansmann, J. Bösenberg, G. D'Amico, I. Mattis, L. Mona, U. Wandinger, V. Amiridis, L

  11. Major soil element (Ca, Mg, K, Na, Al, Fe) distribution along the Qinghai-Tibet Railway

    NASA Astrophysics Data System (ADS)

    Wang, Z.; Zhang, Y.; Zhang, H.; Ding, M.; Lin, X.

    2011-12-01

    that in other type soil. The element content of the Matti-Gelic Cambosols was relatively lower, except for K. (4) The differences in parent materials and soil types may be the reasons for the spatial distribution of major soil elements observed. Key words: Tibetan Plateau, Qinghai-Tibet Railway, soil element, spatial distribution Foundation: National Basic Research Program of China, No. 2005CB422006 and 2010CB951704; National Natural Science Foundation of China, No. 90202012 and 40801042.

  12. Systematic analytical and numerical studies of highly correlated electron systems

    NASA Astrophysics Data System (ADS)

    Tsai, Shan-Wen

    Strong electron correlations in condensed matter systems give rise to a wide range of striking physical properties, producing phenomena as varied as high temperature superconductivity, metal-insulator transitions and the integer and fractional quantum Hall effects. Quantum critical systems also exhibit strong correlations between a large number of degrees of freedom. In this thesis we study these complicated systems using a combination of analytical and numerical approaches. We perform systematic investigations, which adds to the robustness of our results. We develop a new method, based on the density-matrix renormalization-group (DMRG) algorithm combined with finite-size scaling analysis, to study critical behavior in quantum spin chains and extract critical exponents. Accurate results are obtained for spin-1/2 antiferromagnetic chains and the spin-1 chain at the critical point separating the Haldane and the dimerized phases. Disorder in a system can change its properties drastically. Plateau transitions in the integer quantum Hall effect provide the clearest example of quantum critical behavior in a disordered system. We provide analytical proof that the Chalker-Coddington model, which is used to describe the plateau transitions, is quantum critical. Starting from a field theory based on this model, equivalent to a non-Hermitian supersymmetric spin chain, we prove quantum criticality by a Lieb-Schultz-Mattis type theorem. This approach was motivated by numerical results obtained using the DMRG/finite-size scaling method. Our generalized LSM theorem also applies to the spin quantum Hall effect, which can appear in disordered d-wave superconductors with broken time-reversal symmetry. The last part of the thesis is a renormalization-group study of two dimensional interacting electron systems. We obtain results relevant to high-temperature superconductors and also to the family of kappa - (BEDT - TTF)2X organic superconductors. At half filling, the fully nested

  13. Cognitive impairment and functional outcome after stroke associated with small vessel disease

    PubMed Central

    Mok, V; Wong, A; Lam, W; Fan, Y; Tang, W; Kwok, T; Hui, A; Wong, K

    2004-01-01

    Objectives: Although stroke associated with small vessel disease (SSVD) can induce both motor and cognitive impairment, the latter has received less attention. We aimed to evaluate the frequency of the varying severity levels of cognitive impairment, the determinants of severe cognitive impairment, and the association of cognitive impairment with functional outcome after SSVD. Methods: Consecutive patients admitted to hospital because of SSVD were assessed at 3 months after stroke. We performed a semi-structured clinical interview to screen for cognitive symptoms. Severity of cognitive symptoms was graded according to the Clinical Dementia Rating Scale (CDR). Performance on psychometric tests (Mini-Mental State Examination, Alzheimer's Disease Assessment Scale (cognition subscale), Mattis Dementia Rating Scale (initiation/perseverence subscale; MDRS I/P)) of patients of different CDR gradings was compared with that of 42 healthy controls. Basic demographic data, vascular risk factors, stroke severity (National Institute of Health Stroke Scale; NIHSS), pre-stroke cognitive decline (Informant Questionnaire on Cognitive Decline in the Elderly; IQCODE), functional outcome (Barthel index; BI), Instrumental Activities Of Daily Living; IADL), and neuroimaging features (site of recent small infarcts, number of silent small infarcts, white matter changes) were also compared among the groups. Regression analyses were performed to find predictors of severe cognitive impairment and poor functional outcome. Results: Among the 75 included patients, 39 (52%) complained of cognitive symptoms. The number of patients in each CDR grading was as follows: 39 (52%) had a CDR of 0, 26 (34.7%) had a CDR of 0.5, 10 (13.3%) had a CDR of ⩾1. Pre-stroke IQCODE and previous stroke predicted CDR⩾1. The NIHSS was associated with more impaired BI. The NIHSS and MDRS I/P contributed most to impaired IADL. Conclusions: Half of the patients with SSVD complained of varying severity of cognitive

  14. CEILINEX 2015: Validation of calibration methods during the ceilometer inter-comparison

    NASA Astrophysics Data System (ADS)

    Hervo, Maxime

    2016-04-01

    In Europe, more than 700 ceilometers are measuring continuously. These instruments can be used for many applications such as detection of cloud base and aerosol layers height, aerosol profiling or for fog now-casting. However, from different manufacturers exist and the results can vary extensively from one type to another. During the CeiLinEx2015 campaign (Ceilometer Performance Experiment at Lindenberg 2015), 6 types of ceilometers (CL31, CL51, CHM15k, CHM15kx CS135 and LD40) were measuring simultaneously at Lindenberg (Germany) from June to September 2015. Each type was represented by two instruments in order to assess the instrument-to-instrument variability. A companion contribution by Mattis et al. presents an overview of the campaign. The monitoring of the temporal and spatial evolution of aerosol layers like the volcanic ash, is crucial to compare measurements from different sites. Therefore, all instruments need to be calibrated in order to provide consistent results. This contribution will focus on the validation and the comparison of state-of-the-art calibration methods. The calibration methods tested were are the cloud calibration (O'Connor et al., 2004) and the Rayleigh calibration Method (Wiegner and Geiß, 2012). Both methods can be applied without on-site intervention and are thus suitable for automatic networks. Operational automated algorithms based on these methods were developed in the framework of the TOPROF project (ESSEM COST Action ES1303)..The Cloud calibration was found more appropriate for analog instruments with analog signal detection measuring at around 905nm (Vaisala CL51 and CL31 and Campbell Scientific CS135). The Rayleigh was more suitable for photon-counting systems measuring at 1064nm (CHM15k, CHM15kx). For the first time, these methods were tested simultaneously on different instrument types and compared amongst each other. For a dust event occurred on the 13/08/2015, the attenuated backscatter coefficient difference amongst all

  15. A New Estimate for Total Offset on the Southern San Andreas Fault: Implications for Cumulative Plate Boundary Shear in the Northern Gulf of California

    NASA Astrophysics Data System (ADS)

    Darin, M. H.; Dorsey, R. J.

    2012-12-01

    Development of a consistent and balanced tectonic reconstruction for the late Cenozoic San Andreas fault (SAF) in southern California has been hindered for decades by incompatible estimates of total dextral offset based on different geologic cross-fault markers. The older estimate of 240-270 km is based on offset fluvial conglomerates of the middle Miocene Mint Canyon and Caliente Formations west of the SAF from their presumed source area in the northern Chocolate Mountains NE of the SAF (Ehlig et al., 1975; Ehlert, 2003). The second widely cited offset marker is a distinctive Triassic megaporphyritic monzogranite that has been offset 160 ± 10 km between Liebre Mountain west of the SAF and the San Bernadino Mountains (Matti and Morton, 1993). In this analysis we use existing paleocurrent data and late Miocene clockwise rotation in the eastern Transverse Ranges (ETR) to re-assess the orientation of the piercing line used in the 240 km-correlation, and present a palinspastic reconstruction that satisfies all existing geologic constraints. Our reconstruction of the Mint Canyon piercing line reduces the original estimate of 240-270 km to 195 ± 15 km of cumulative right-lateral slip on the southern SAF (sensu stricto), which is consistent with other published estimates of 185 ± 20 km based on correlative basement terranes in the Salton Trough region. Our estimate of ~195 km is consistent with the lower estimate of ~160 km on the Mojave segment because transform-parallel extension along the southwestern boundary of the ETR during transrotation produces ~25-40 km of displacement that does not affect offset markers of the Liebre/San Bernadino correlation located northwest of the ETR rotating domain. Reconciliation of these disparate estimates places an important new constraint on the total plate boundary shear that is likely accommodated in the adjacent northern Gulf of California. Global plate circuit models require ~650 km of cumulative Pacific-North America (PAC

  16. Integrating geology and geomorphology; the key to unlocking Quaternary tectonic framework of the San Andreas Fault zone in the San Gorgonio Pass region, southern California

    NASA Astrophysics Data System (ADS)

    Kendrick, K. J.; Matti, J. C.

    2012-12-01

    older than 500 ka, has a wide spatial footprint along a N-S axis, and Holocene alluvium is disrupted by numerous fault scarps. By contrast, south of PPB the SGPFZ consists of fewer thrust-fault strands, has a relatively narrow footprint, and faults breaking Holocene deposits are uncommon. The San Bernardino strand of the SAF intersects the SGPFZ at about the boundary between these two domains. Morphometric data indicate that the KPB has undergone significantly greater uplift than the PPB since inception of the San Bernardino strand, proposed by Matti and Morton (1993) to have occurred at ~125ka. Age estimates associated with the PPB and DGB allow us to broadly estimate relative uplift rates. Drainage reconstruction of the Whitewater River and its tributaries across the YRB likewise allow us to validate and refine the uplift estimated by Spotila and others (2001). YRB has been uplifted relative to SGB since the inception of the Mill Creek Strand of the SAF.

  17. Fragmented Landscapes in the San Gorgonio Pass Region: Insights into Quaternary Strain History of the Southern San Andreas Fault System

    NASA Astrophysics Data System (ADS)

    Kendrick, K. J.; Matti, J. C.; Landis, G. P.; Alvarez, R. M.

    2006-12-01

    The San Gorgonio Pass (SGP) region is a zone of structural complexity within the southern San Andreas Fault system that is characterized by (1) multiple strands of the San Andreas Fault (SAF), (2) intense and diverse microseismicity, (3) contraction within the SGP fault zone (SGPfz), and (4) complex and diverse landforms - all a consequence of structural complications in the vicinity of the southeastern San Bernardino Mountains (SBM). Multiple strands of the SAF zone in the SGP region partition the landscape into discrete geomorphic/geologic domains, including: San Gorgonio Mountain (SGM), Yucaipa Ridge (YR), Kitching Peak (KP), Pisgah Peak (PP), and Coachella Valley (CV) domains. The morphology of each domain reflects the tectonic history unique to that region. Development of the SGP knot in the Mission Creek strand of the SAF (SAFmi) led to westward deflection of the SAFmi, juxtaposition of the KP, PP, and SGM domains, initiation of uplift of YR domain along thrust faults in headwaters of San Gorgonio River, and development of the San Jacinto Fault. Slip on the SAF diminished as a result, thereby allowing integrated drainage systems to develop in the greater SGP region. San Gorgonio River, Whitewater River, and Mission Creek are discrete drainages that transport sediment across the SGM, YR, PP, KP, and CV domains into alluvial systems peripheral to the SGP region. There, depositional units (San Timoteo Formation, upper member, deformed gravels of Whitewater River) all contain clasts of SBM-type and San Gabriel Mountain-type basement, thus constraining slip on the SAF in the SGP region. Middle and late Pleistocene slip on the Mill Creek strand of the SAF (SAFm) in the SGP region has attempted to bypass the SGP knot, and has disrupted landscapes established during SAFmi quiescence. Restoration of right-slip on the SAFm is key to deciphering landscape history. Matti and others (1985, 1992) proposed that a bi-lobed alluvial deposit in the Raywood Flats area has been

  18. CBP PHASE I CODE INTEGRATION

    SciTech Connect

    Smith, F.; Brown, K.; Flach, G.; Sarkar, S.

    2011-09-30

    The goal of the Cementitious Barriers Partnership (CBP) is to develop a reasonable and credible set of software tools to predict the structural, hydraulic, and chemical performance of cement barriers used in nuclear applications over extended time frames (greater than 100 years for operating facilities and greater than 1000 years for waste management). The simulation tools will be used to evaluate and predict the behavior of cementitious barriers used in near surface engineered waste disposal systems including waste forms, containment structures, entombments, and environmental remediation. These cementitious materials are exposed to dynamic environmental conditions that cause changes in material properties via (i) aging, (ii) chloride attack, (iii) sulfate attack, (iv) carbonation, (v) oxidation, and (vi) primary constituent leaching. A set of state-of-the-art software tools has been selected as a starting point to capture these important aging and degradation phenomena. Integration of existing software developed by the CBP partner organizations was determined to be the quickest method of meeting the CBP goal of providing a computational tool that improves the prediction of the long-term behavior of cementitious materials. These partner codes were selected based on their maturity and ability to address the problems outlined above. The GoldSim Monte Carlo simulation program (GTG 2010a, GTG 2010b) was chosen as the code integration platform (Brown & Flach 2009b). GoldSim (current Version 10.5) is a Windows based graphical object-oriented computer program that provides a flexible environment for model development (Brown & Flach 2009b). The linking of GoldSim to external codes has previously been successfully demonstrated (Eary 2007, Mattie et al. 2007). GoldSim is capable of performing deterministic and probabilistic simulations and of modeling radioactive decay and constituent transport. As part of the CBP project, a general Dynamic Link Library (DLL) interface was

  19. EDITORIAL: Incoming Editor-in-Chief

    NASA Astrophysics Data System (ADS)

    Lidström, Suzanne

    2012-04-01

    , in his hands, the expansion continued and the transition to electronic production took place. In 2005, an agreement was signed with IOP Publishing and the bustling production work of the in-house team moved abroad to Bristol, leaving just the Editor-in-Chief to man the ship at the Royal Swedish Academy of Sciences. In 2011, however, as Roger prepared to step down, submissions had reached astounding levels as is evident from figure 1: that year, almost 1500 manuscripts were received by Physica Scripta, now acknowledged to be amongst the fastest growing journals in IOP Publishing, when measured in these terms. The year on year increase stands at 20% and, once again, of the extensive range of topics covered, condensed matter physics had been identified as the subject area in most need of attention because the burden of reviewing had become too great for one editor to oversee alone. Thus, when I joined Physica Scripta in January of this year, securing new External Editors for this field was perceived to be the most urgent task. It is, therefore, with the greatest of pleasure that I am able to announce the arrival of two new editors for this section: Professors David Keen and Tapio Rantala. Physica Scripta statistics Figure 1. The annual submissions made to Physica Scripta in recent years have rocketed and the rejection rate (given as a percentage) has increased rapidly. The modest increase in the number of articles accepted (shaded in blue) reflects a deliberate policy to augment the scientific quality. Professor Rantala has been selected by the Finnish Physical Society to replace Professor Matti Manninen, who is stepping down as the Finnish representative on the journal's Editorial Board. Professor Rantala is a prominent theorist and has been engaged in active research in a number of fields. In his early work, he was interested in surface science and molecular physics, however his expertise is predominantly in the domain of solid or materials physics related to

  20. News and Announcements

    NASA Astrophysics Data System (ADS)

    1999-05-01

    Supplementary Materials The number of supplementary materials that accompany print articles has grown and also become more varied. The new guidelines for lab experiments call for supplementary materials in most cases, so that the actual materials used in lab can be made available. The From Past Issues column edited by Kathryn Williams and many of the technology columns frequently have supplements for JCE Online. An especially interesting supplement that we would like to call to the attention of readers is a collection of videos from the E. O. Lawrence Berkeley National Laboratory, based on interviews with nuclear chemists who have discovered and studied the heaviest elements. These movies accompany the Viewpoints article, "Chemistry of the Heaviest Elements-One Atom at a Time" by Darleane C. Hoffman and Diana M. Lee. The titles of the movies are listed below; illustrative stills are shown at the bottom of the page. Researchers involved with the segments about Lawrencium include Robert Silva, Torbjorn Sikkeland, Matti Nurmia, Robert Latimer, and Albert Ghiorso, all of whom are from the Lawrence Berkeley Laboratory. (QuickTime 3 is needed in order to view the videos; it can be downloaded free from http://www.apple.com.)

    • A Brief Note about Plutonium, by Glenn Seaborg
    • Plutonium and Why It Was Kept a Secret
    • The Prediction of the Actinide Series, by Glenn Seaborg
    • First Chemical Separation of Lawrencium at Lawrence Radiation Laboratory in 1970
    • The HILAC or Heavy-Ion Linear Accelerator
    • Discovery of Lawrencium
    • How To Collect Lawrencium Atoms
    • The Discovery of Element 106-Finally
    • The Naming of Element 106
    • The Limits of Discovering the Heavy Elements
    • What Good Is a Heavy Element?
    To see these videos, view the Supplements of http://JChemEd.chem.wisc.edu/Journal/Issues/1999/Mar/abs331.html. People: Glenn Seaborg Glenn Seaborg, frequent contributor

  1. EDITORIAL: Focus on Cloaking and Transformation Optics

    NASA Astrophysics Data System (ADS)

    Leonhardt, Ulf; Smith, David R.

    2008-11-01

    multi-frequency cloaking Andrea Alù and Nader Engheta Electromagnetic cloaking devices for TE and TM polarizations Filiberto Bilotti, Simone Tricarico and Lucio Vegni An aberration-free lens with zero F-number D Schurig Transformational optics of plasmonic metamaterials I I Smolyaninov An acoustic metafluid: realizing a broadband acoustic cloak J B Pendry and Jensen Li On the possibility of metamaterial properties in spin plasmas G Brodin and M Marklund A homogenization route towards square cylindrical acoustic cloaks Mohamed Farhat, Sébastien Guenneau, Stefan Enoch, Alexander Movchan, Frédéric Zolla and André Nicolet Transformation optics: approaching broadband electromagnetic cloaking A V Kildishev, W Cai, U K Chettiar and V M Shalaev Generalized field-transforming metamaterials Sergei A Tretyakov, Igor S Nefedov and Pekka Alitalo Electromagnetic beam modulation through transformation optical structures Xiaofei Xu, Yijun Feng and Tian Jiang Superantenna made of transformation media Ulf Leonhardt and Tomáš Tyc Material parameters and vector scaling in transformation acoustics Steven A Cummer, Marco Rahm and David Schurig Isotropic transformation optics: approximate acoustic and quantum cloaking Allan Greenleaf, Yaroslav Kurylev, Matti Lassas and Gunther Uhlmann Transformation optical designs for wave collimators, flat lenses and right-angle bends Do-Hoon Kwon and Douglas H Werner Alternative derivation of electromagnetic cloaks and concentrators A D Yaghjian and S Maci Solutions in folded geometries, and associated cloaking due to anomalous resonance Graeme W Milton, Nicolae-Alexandru P Nicorovici, Ross C McPhedran, Kirill Cherednichenko and Zubin Jacob Finite wavelength cloaking by plasmonic resonance N-A P Nicorovici, R C McPhedran, S Enoch and G Tayeb

  2. EDITORIAL: Incoming Editor-in-Chief

    NASA Astrophysics Data System (ADS)

    Lidström, Suzanne

    2012-04-01

    , in his hands, the expansion continued and the transition to electronic production took place. In 2005, an agreement was signed with IOP Publishing and the bustling production work of the in-house team moved abroad to Bristol, leaving just the Editor-in-Chief to man the ship at the Royal Swedish Academy of Sciences. In 2011, however, as Roger prepared to step down, submissions had reached astounding levels as is evident from figure 1: that year, almost 1500 manuscripts were received by Physica Scripta, now acknowledged to be amongst the fastest growing journals in IOP Publishing, when measured in these terms. The year on year increase stands at 20% and, once again, of the extensive range of topics covered, condensed matter physics had been identified as the subject area in most need of attention because the burden of reviewing had become too great for one editor to oversee alone. Thus, when I joined Physica Scripta in January of this year, securing new External Editors for this field was perceived to be the most urgent task. It is, therefore, with the greatest of pleasure that I am able to announce the arrival of two new editors for this section: Professors David Keen and Tapio Rantala. Physica Scripta statistics Figure 1. The annual submissions made to Physica Scripta in recent years have rocketed and the rejection rate (given as a percentage) has increased rapidly. The modest increase in the number of articles accepted (shaded in blue) reflects a deliberate policy to augment the scientific quality. Professor Rantala has been selected by the Finnish Physical Society to replace Professor Matti Manninen, who is stepping down as the Finnish representative on the journal's Editorial Board. Professor Rantala is a prominent theorist and has been engaged in active research in a number of fields. In his early work, he was interested in surface science and molecular physics, however his expertise is predominantly in the domain of solid or materials physics related to

  3. EDITORIAL: 'Best article' prize for the 5th anniversary of Environmental Research Letters 'Best article' prize for the 5th anniversary of Environmental Research Letters

    NASA Astrophysics Data System (ADS)

    Kammen, Dan; Wright, Guillaume

    2011-12-01

    To celebrate the 5th anniversary of Environmental Research Letters (ERL) the publishers of the journal, IOP Publishing, have awarded a prize for the five best articles published in ERL since the journal began in 2006. The procedure for deciding the winning articles was as thorough as possible to ensure that the most outstanding articles would win the prize. A shortlist of 25 nominated research articles, five for each year since ERL was launched, which were chosen based on a range of criteria including novelty, scientific impact, readership, broad appeal and wider media coverage, was selected. The ERL Editorial Board then assessed and rated these 25 articles in order to choose a winning article for each year. We would like to announce that the following articles have been awarded ERL's 5th anniversary best article prize: 2006/7 The Bodélé depression: a single spot in the Sahara that provides most of the mineral dust to the Amazon forest Ilan Koren, Yoram J Kaufman, Richard Washington, Martin C Todd, Yinon Rudich, J Vanderlei Martins and Daniel Rosenfeld 2006 Environ. Res. Lett. 1 014005 2008 Causes and impacts of the 2005 Amazon drought Ning Zeng, Jin-Ho Yoon, Jose A Marengo, Ajit Subramaniam, Carlos A Nobre, Annarita Mariotti and J David Neelin 2008 Environ. Res. Lett. 3 014002 2009 How difficult is it to recover from dangerous levels of global warming? J A Lowe, C Huntingford, S C B Raper, C D Jones, S K Liddicoat and L K Gohar 2009 Environ. Res. Lett. 4 014012 2010 Is physical water scarcity a new phenomenon? Global assessment of water shortage over the last two millennia Matti Kummu, Philip J Ward, Hans de Moel and Olli Varis 2010 Environ. Res. Lett. 5 034006 2011 Implications of urban structure on carbon consumption in metropolitan areas Jukka Heinonen and Seppo Junnila 2011 Environ. Res. Lett. 6 014018 Our congratulations go to these authors. In recognition of their outstanding work, we are delighted to offer all of the authors of the winning articles free

  4. Obituary: Frank Culver Jones, 1932-2007

    NASA Astrophysics Data System (ADS)

    Ormes, Johnathan F.; Streitmatter, Robert E.

    2007-12-01

    everyone from technicians to scientists and managers. This generosity resulted in his becoming the first senior research scientist to be honored with the Laboratory's Peer Award. Survivors include his wife of 52 years, Ardythe Grube Jones of Silver Spring, Maryland, two children, Cheryl Mattis of Columbia and Timothy Jones of Silver Spring, two brothers, and four grandchildren.

  5. News and Announcements

    NASA Astrophysics Data System (ADS)

    1999-05-01

    Supplementary Materials The number of supplementary materials that accompany print articles has grown and also become more varied. The new guidelines for lab experiments call for supplementary materials in most cases, so that the actual materials used in lab can be made available. The From Past Issues column edited by Kathryn Williams and many of the technology columns frequently have supplements for JCE Online. An especially interesting supplement that we would like to call to the attention of readers is a collection of videos from the E. O. Lawrence Berkeley National Laboratory, based on interviews with nuclear chemists who have discovered and studied the heaviest elements. These movies accompany the Viewpoints article, "Chemistry of the Heaviest Elements-One Atom at a Time" by Darleane C. Hoffman and Diana M. Lee. The titles of the movies are listed below; illustrative stills are shown at the bottom of the page. Researchers involved with the segments about Lawrencium include Robert Silva, Torbjorn Sikkeland, Matti Nurmia, Robert Latimer, and Albert Ghiorso, all of whom are from the Lawrence Berkeley Laboratory. (QuickTime 3 is needed in order to view the videos; it can be downloaded free from http://www.apple.com.)

    • A Brief Note about Plutonium, by Glenn Seaborg
    • Plutonium and Why It Was Kept a Secret
    • The Prediction of the Actinide Series, by Glenn Seaborg
    • First Chemical Separation of Lawrencium at Lawrence Radiation Laboratory in 1970
    • The HILAC or Heavy-Ion Linear Accelerator
    • Discovery of Lawrencium
    • How To Collect Lawrencium Atoms
    • The Discovery of Element 106-Finally
    • The Naming of Element 106
    • The Limits of Discovering the Heavy Elements
    • What Good Is a Heavy Element?
    To see these videos, view the Supplements of http://JChemEd.chem.wisc.edu/Journal/Issues/1999/Mar/abs331.html. People: Glenn Seaborg Glenn Seaborg, frequent contributor

  6. FOREWORD: The 70th birthday of Professor Stig Stenholm The 70th birthday of Professor Stig Stenholm

    NASA Astrophysics Data System (ADS)

    Suominen, Kalle-Antti

    2010-09-01

    information [7] and in Stockholm he had, again, very successful postdocs such as Ulf Leonhardt. Finally, in 2005, Stig Stenholm retired, although he is still active, writing papers, taking part in conferences and making research visits. We honoured his 70th birthday at the CEWQO2009 conference, and hope that the future provides us with further opportunities for such events. Looking at the obituary of Dirk ter Haar, I see that his style with students reminds me of Stig's approach. In my opinion, Stig expects independence and initiative from a student, giving perhaps a broad topic in which the student is expected to find his or her own way, whilst working perhaps with a postdoc. Juha Javanainen has talked about the 'sink or swim' style (not referring to Stig, though). There is a famous series of children's books about Moomin trolls by Tove Jansson (another Swedish-speaking Finn like Stig). In one of them, the Moomin find in early spring a small flower in a patch of land uncovered by snow, pushing its way up. One of them wants to cover it against frost during the night, but another says 'Don't, it'll fare better later if it has some difficulties at first'. At CEWQO2009 Stig gave the full list of his finished PhD students: Rainer Salomaa (1973), Temba Dlodlo (1980), Juha Javanainen (1980), Markus Lindberg (1985), Matti Kaivola (1985), Birger Ståhlberg (1985), Kalle-Antti Suominen (1992), Mackillo Kira (1995), Päivi Törmä (1996), Asta Paloviita (1997), Patrik Öhberg (1998), Martti Havukainen (1999), Erika Andersson (2000), Pawel Piwnicki (2001), Åsa Larson (2001), Markku Jääskeläinen (2003), and Jonas Larson (2005). One should also mention Erkki Kyrölä, who eventually graduated at Rochester and Olli Serimaa, who never graduated but published some important early-stage laser cooling work. As a final note I must mention a passion that Stig and I share, namely books. I have nearly 400 professional physics and mathematics books, but I am certain that the size of Stig

  7. EDITORIAL: Special issue on optical neural engineering: advances in optical stimulation technology Special issue on optical neural engineering: advances in optical stimulation technology

    NASA Astrophysics Data System (ADS)

    Shoham, Shy; Deisseroth, Karl

    2010-08-01

    C, Mattis J, Prakash R, Diester I, Goshen I, Thompson K R, Deisseroth K 2010 Molecular and cellular approaches for diversifying and extending optogenetics Cell 141 154-65 [18] Zhang F, Gradinaru V, Adamantidis A R, Durand R, Airan R D, de Lecea L and Deisseroth K 2010 Optogenetic interrogation of neural circuits: technology for probing mammalian brain structures Nat. Protoc. 5 439-56 [19] Wells J, Kao C, Mariappan K, Albea J, Duco Jansen E, Konrad P and Mahadevan-Jansen A 2005 Optical stimulation of neural tissue in vivo Opt. Lett. 30 504-6 [20] Izzo A D, Richter C P, Jansen E D and Walsh J T Jr 2006 Laser stimulation of the auditory nerve Lasers Surg. Med. 38 745-53 [21] Richter C P, Izzo A D, Wells J, Jansen E D and Walsh J T Jr 2010 Neural stimulation with optical radiation Laser Photonics Rev. available at doi:10.1002/lpor.200900044 [22] Nikolenko V, Peterka D S and Yuste R 2010 A portable laser photostimulation and imaging microscope J. Neural Eng. 7 045001 [23] Golan L, Reutsky I, Farah N and Shoham S 2009 Design and characteristics of holographic neural photo-stimulation systems J. Neural Eng. 6 066004 [24] Losavio B E, Iyer V, Patel S and Saggau P 2010 Acousto-optical laser scanning for multi-site photo-stimulation of single neurons in vitro J. Neural Eng. 7 045002 [25] Duemani Reddy G, Kelleher K, Fink R and Saggau P 2008 Three-dimensional random access multiphoton microscopy for functional imaging of neuronal activity Nat. Neurosci. 11 713-20 [26] Grewe B F, Langer D, Kasper H, Kampa B M and Helmchen F 2010 High-speed in vivo calcium imaging reveals neuronal network activity with near-millisecond precision Nat. Methods 7 399-405 [27] Pikov V, Arakaki X, Harrington M, Fraser S E and Siegel P H 2010 Modulation of neuronal activity and plasma membrane propertiess with low-power millimeter waves in organotypic cortical slices J. Neural Eng. 7 045003 [28] Liang S et al 2009 Temperature-dependent activation of neurons by continuous near-infrared laser Cell