Sample records for phases case description

  1. Characterization of Flow Dynamics and Reduced-Order Description of Experimental Two-Phase Pipe Flow

    NASA Astrophysics Data System (ADS)

    Viggiano, Bianca; SkjæRaasen, Olaf; Tutkun, Murat; Cal, Raul Bayoan

    2017-11-01

    Multiphase pipe flow is investigated using proper orthogonal decomposition for tomographic X-ray data, where holdup, cross sectional phase distributions and phase interface characteristics are obtained. Instantaneous phase fractions of dispersed flow and slug flow are analyzed and a reduced order dynamical description is generated. The dispersed flow displays coherent structures in the first few modes near the horizontal center of the pipe, representing the liquid-liquid interface location while the slug flow case shows coherent structures that correspond to the cyclical formation and breakup of the slug in the first 10 modes. The reconstruction of the fields indicate that main features are observed in the low order dynamical descriptions utilizing less than 1 % of the full order model. POD temporal coefficients a1, a2 and a3 show interdependence for the slug flow case. The coefficients also describe the phase fraction holdup as a function of time for both dispersed and slug flow. These flows are highly applicable to petroleum transport pipelines, hydroelectric power and heat exchanger tubes to name a few. The mathematical representations obtained via proper orthogonal decomposition will deepen the understanding of fundamental multiphase flow characteristics.

  2. Doppler-broadened NICE-OHMS beyond the cavity-limited weak absorption condition - I. Theoretical description

    NASA Astrophysics Data System (ADS)

    Ma, Weiguang; Silander, Isak; Hausmaninger, Thomas; Axner, Ove

    2016-01-01

    Doppler-broadened (Db) noise-immune cavity-enhanced optical heterodyne molecular spectrometry (NICE-OHMS) is conventionally described by an expression (here referred to as the CONV expression) that is restricted to the case when the single-pass absorbance, α0L, is much smaller than the empty cavity losses, π/F [here termed the conventional cavity-limited weak absorption (CCLWA) condition]. This limits the applicability of the technique, primarily its dynamic range and calibration capability. To remedy this, this work derives extended descriptions of Db NICE-OHMS that are not restricted to the CCLWA condition. First, the general principles of Db NICE-OHMS are scrutinized in some detail. Based solely upon a set of general assumptions, predominantly that it is appropriate to linearize the Beer-Lambert law, that the light is modulated to a triplet, and that the Pound-Drever-Hall sidebands are fully reflected, a general description of Db NICE-OHMS that is not limited to any specific restriction on α0L vs. π/F, here referred to as the FULL description, is derived. However, this description constitutes a set of equations to which no closed form solution has been found. Hence, it needs to be solved numerically (by iterations), which is inconvenient. To circumvent this, for the cases when α0L<π/F but without the requirement that the stronger CCLWA condition needs to be fulfilled, a couple of simplified extended expressions that are expressible in closed analytical form, referred to as the extended locking and extended transmission description, ELET, and the extended locking and full transmission description, ELFT, have been derived. An analysis based on simulations validates the various descriptions and assesses to which extent they agree. It is shown that in the CCLWA limit, all extended descriptions revert to the CONV expression. The latter one deviates though from the extended ones for α0L around and above 0.1π/F. The two simplified extended descriptions agree with the FULL description for a larger range of α0 L than the CONV expression, viz. for the ELET description for α0L up to 0.3π/F and for ELFT for α0L up to 0.6 or 1.0 π/F (depending on the mode of detection). It is then demonstrated that the conventional view of Db NICE-OHMS, which states that the out-of-phase and the in-phase signals can be referred to as a pure absorption and dispersion signal, respectively, breaks down when the CCLWA condition does not hold. In this case, the out-of-phase signal is additionally affected by the phase shifts of the laser components (i.e. dispersion) while the in-phase signal is also influenced by their attenuation. Access to new descriptions broadens considerably the dynamic range of Db NICE-OHMS and facilitates calibration using standard references samples, and thereby its applicability.

  3. Two-phase flow simulation of scour around a cylindrical pile

    NASA Astrophysics Data System (ADS)

    Nagel, T.; Chauchat, J.; Bonamy, C.; Liu, X.; Cheng, Z.; Hsu, T. J.

    2017-12-01

    Scour around structures is a major engineering issue that requires a detailed description of the flow field but also a consistent description of sediment transport processes that could not only be related to bed shear stress, like Shields parameter based sediment transport formula. In order to address this issue we used a multi-dimensional two-phase flow solver, sedFoam-2.0 (Chauchat et al., GMD 2017) implemented under the open-source CFD toolbox OpenFoam. Three-dimensional simulations have been performed on Roulund et al. (JFM 2005) configurations for clear-water and live bed cases. The k-omega model from Wilcox (AIAA Journal 2006) is used for the turbulent stress and the granular rheology μ(I) is used for the granular stress in the live bed case. The hydrodynamic is validated on the clear water case and the numerical results obtained for the live bed case provide a proof of concept that two-phase flow model is applicable to such problem with quantitative results for the prediction of scour depth upstream and downstream the cylinder at short timescales, up to 300s. Analyzing the simulation results in term of classical dimensionless sediment transport flux versus Shields parameter allows to get more insight into the fine scale sediment transport mechanisms involved in the scour process.

  4. The modelling of heat, mass and solute transport in solidification systems

    NASA Technical Reports Server (NTRS)

    Voller, V. R.; Brent, A. D.; Prakash, C.

    1989-01-01

    The aim of this paper is to explore the range of possible one-phase models of binary alloy solidification. Starting from a general two-phase description, based on the two-fluid model, three limiting cases are identified which result in one-phase models of binary systems. Each of these models can be readily implemented in standard single phase flow numerical codes. Differences between predictions from these models are examined. In particular, the effects of the models on the predicted macro-segregation patterns are evaluated.

  5. Towards a Unified Quark-Hadron-Matter Equation of State for Applications in Astrophysics and Heavy-Ion Collisions

    NASA Astrophysics Data System (ADS)

    Bastian, Niels-Uwe; Blaschke, David; Fischer, Tobias; Röpke, Gerd

    2018-05-01

    We outline an approach to a unified equation of state for quark-hadron matter on the basis of a $\\Phi-$derivable approach to the generalized Beth-Uhlenbeck equation of state for a cluster decomposition of thermodynamic quantities like the density. To this end we summarize the cluster virial expansion for nuclear matter and demonstrate the equivalence of the Green's function approach and the $\\Phi-$derivable formulation. For an example, the formation and dissociation of deuterons in nuclear matter is discussed. We formulate the cluster $\\Phi-$derivable approach to quark-hadron matter which allows to take into account the specifics of chiral symmetry restoration and deconfinement in triggering the Mott-dissociation of hadrons. This approach unifies the description of a strongly coupled quark-gluon plasma with that of a medium-modified hadron resonance gas description which are contained as limiting cases. The developed formalism shall replace the common two-phase approach to the description of the deconfinement and chiral phase transition that requires a phase transition construction between separately developed equations of state for hadronic and quark matter phases. Applications to the phenomenology of heavy-ion collisions and astrophysics are outlined.

  6. Coupled Mode Formalism: Connecting Phasor, Matrix, and Geometrical Approaches

    DTIC Science & Technology

    2014-05-30

    the Poincare sphere in classical optics, and was generalized to incoherent light as the Stokes and Mueller approach [4]. The Stokes description reduces...to the Poincare sphere description when one treats monochromatic light, and we restrict ourselves to this case. Background There are several...waves, cast as plane waves of the form g(z, t) = f(z − vt) = Aej(ω t −k z) , (1) namely a sinusoidal wave travelling in the positive z direction at phase

  7. Quantum critical dynamics of the boson system in the Ginzburg-Landau model

    NASA Astrophysics Data System (ADS)

    Vasin, M. G.

    2014-12-01

    The quantum critical dynamics of the quantum phase transitions is considered. In the framework of the unified theory, based on the Keldysh technique, we consider the crossover from the classical to the quantum description of the boson many-body system dynamics close to the second order quantum phase transition. It is shown that in this case the upper critical space dimension of this model is dc+=2, therefore the quantum critical dynamics approach is useful in case of d<2. In the one-dimension system the phase coherence time does diverge at the quantum critical point, gc, and has the form of τ∝-ln∣g-gc∣/∣g-gc∣, the correlation radius diverges as rc∝∣g-gc∣(ν=0.6).

  8. Launching College Students on Academic Probation into the First Phase of Self-Efficacy: A Descriptive Case Survey

    ERIC Educational Resources Information Center

    Holland, Rochelle

    2005-01-01

    The purpose of this case survey was to examine the reasons that students provide regarding why they are on academic probation and the efficacy of discussing the family life cycle among this group. Initially, a pilot population of 93 students on academic probation, who are a part of a multi-cultural community college in New York City, were surveyed…

  9. Dynamics of heterogeneous oscillator ensembles in terms of collective variables

    NASA Astrophysics Data System (ADS)

    Pikovsky, Arkady; Rosenblum, Michael

    2011-04-01

    We consider general heterogeneous ensembles of phase oscillators, sine coupled to arbitrary external fields. Starting with the infinitely large ensembles, we extend the Watanabe-Strogatz theory, valid for identical oscillators, to cover the case of an arbitrary parameter distribution. The obtained equations yield the description of the ensemble dynamics in terms of collective variables and constants of motion. As a particular case of the general setup we consider hierarchically organized ensembles, consisting of a finite number of subpopulations, whereas the number of elements in a subpopulation can be both finite or infinite. Next, we link the Watanabe-Strogatz and Ott-Antonsen theories and demonstrate that the latter one corresponds to a particular choice of constants of motion. The approach is applied to the standard Kuramoto-Sakaguchi model, to its extension for the case of nonlinear coupling, and to the description of two interacting subpopulations, exhibiting a chimera state. With these examples we illustrate that, although the asymptotic dynamics can be found within the framework of the Ott-Antonsen theory, the transients depend on the constants of motion. The most dramatic effect is the dependence of the basins of attraction of different synchronous regimes on the initial configuration of phases.

  10. Command and Control of Guerrilla Groups in the Philippines, 1941-1945

    DTIC Science & Technology

    2017-05-25

    However, the phasing concept in this case seems ex post facto , rather than descriptive of any initial design. Especially in its early days, the trajectory... post -independence era. They apply a framework that examines the environment, organization, tactics, doctrine, and technology of each phase of history...defenses on Mindanao and destroyed the bulk of Sharp’s force, though the command post at Del Monte remained intact.33 On May 9, Sharp met with a

  11. THE ROLE OF METASTABLE STATES IN POLYMER PHASE TRANSITIONS: Concepts, Principles, and Experimental Observations

    NASA Astrophysics Data System (ADS)

    Cheng, Stephen Z. D.; Keller, Andrew

    1998-08-01

    Polymer phases can be described in the same way as phases in other condensed matter using a number density operator and its correlation functions. This description requires the understanding of symmetry operations and order at different atomic and molecular levels. Statistical mechanics provides a link between the microscopic description of the structure and motion and the macroscopic thermodynamic properties. Within the limits of the laws of thermodynamics, polymers exhibit a rich variety of phase transition behaviors. By definition, a first-order phase transition describes a transformation that involves a sudden change of thermodynamic properties at its transition temperature, whereas higher-order phase transitions are classified as critical phenomena. Of special interest is the role of metastability in phase and phase transition behaviors. Although a metastable state possesses a local free energy minimum, it is not at the global equilibrium. Furthermore, metastable states can also be associated with phase sizes. Metastable behavior is also observed in phase transformations that are impeded by kinetic limitations along the pathway to thermodynamic equilibrium. This is illustrated in structural and morphological investigations of crystallization and mesophase transitions, liquid-liquid phase separation, vitrification, and gel formation, as well as combinations of transformation processes. In these cases, the metastable state often becomes the dominant state for the entire system and is observed over a range of time and size scales. This review describes the general principles of metastability in polymer phases and phase transitions and provides illustrations from current experimental works in selected areas.

  12. Application of mid-infrared pulses for quasi-phase-matching of high-order harmonics in silver plasma.

    PubMed

    Ganeev, Rashid A; Husakou, Anton; Suzuki, Masayuki; Kuroda, Hiroto

    2016-02-22

    We demonstrate the quasi-phase-matching of a group of harmonics generated in Ag multi-jet plasma using tunable pulses in the region of 1160 - 1540 nm and their second harmonic emission. The numerical treatment of this effect includes microscopic description of the harmonic generation, propagation of the pump pulse, and the propagation of the generated harmonics. We obtained more than 30-fold growth of harmonics at the conditions of quasi-phase-matching in the region of 35 nm using eight-jet plasma compared with the case of imperforated plasma.

  13. Ab initio construction of magnetic phase diagrams in alloys: The case of Fe 1-xMn xPt

    DOE PAGES

    Pujari, B. S.; Larson, P.; Antropov, V. P.; ...

    2015-07-28

    A first-principles approach to the construction of concentration-temperature magnetic phase diagrams of metallic alloys is presented. The method employs self-consistent total energy calculations based on the coherent potential approximation for partially ordered and noncollinear magnetic states and is able to account for competing interactions and multiple magnetic phases. The application to the Fe 1–xMn xPt “magnetic chameleon” system yields the sequence of magnetic phases at T = 0 and the c-T magnetic phase diagram in good agreement with experiment, and a new low-temperature phase is predicted at the Mn-rich end. The importance of non-Heisenberg interactions for the description of themore » magnetic phase diagram is demonstrated.« less

  14. Gapless edges of 2d topological orders and enriched monoidal categories

    NASA Astrophysics Data System (ADS)

    Kong, Liang; Zheng, Hao

    2018-02-01

    In this work, we give a mathematical description of a chiral gapless edge of a 2d topological order (without symmetry). We show that the observables on the 1+1D world sheet of such an edge consist of a family of topological edge excitations, boundary CFT's and walls between boundary CFT's. These observables can be described by a chiral algebra and an enriched monoidal category. This mathematical description automatically includes that of gapped edges as special cases. Therefore, it gives a unified framework to study both gapped and gapless edges. Moreover, the boundary-bulk duality also holds for gapless edges. More precisely, the unitary modular tensor category that describes the 2d bulk phase is exactly the Drinfeld center of the enriched monoidal category that describes the gapless/gapped edge. We propose a classification of all gapped and chiral gapless edges of a given bulk phase. In the end, we explain how modular-invariant bulk rational conformal field theories naturally emerge on certain gapless walls between two trivial phases.

  15. Spin dynamics of antiferromagnets in the presence of a homogeneous magnetization

    NASA Astrophysics Data System (ADS)

    Kirkpatrick, T. R.; Belitz, D.

    2017-06-01

    We use general hydrodynamic equations to determine the long-wavelength spin excitations in isotropic antiferromagnets in the presence of a homogeneous magnetization. The latter may be induced, such as in antiferromagnets in an external magnetic field, or spontaneous, such as in ferrimagnetic or canted phases that are characterized by the coexistence of antiferromagnetic and ferromagnetic order. Depending on the physical situation, we find propagating spin waves that are gapped in some cases and gapless in others, diffusive modes, or relaxational modes. The excitation spectra turn out to be qualitatively different depending on whether or not the homogeneous magnetization is a conserved quantity. The results lay the foundation for a description of a variety of quantum phase transitions, including the transition from a ferromagnetic metal to an antiferromagnetic one, and the spin-flop transitions that are observed in some antiferromagnets. They also are crucial for incorporating weak localization and Altshuler-Aronov effects into the descriptions of quantum phases in both clean and disordered magnetic metals.

  16. Fort Hood Solar Total Energy Project. Volume II. Preliminary design. Part 1. System criteria and design description. Final report

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

    None,

    1979-01-01

    This volume documents the preliminary design developed for the Solar Total Energy System to be installed at Fort Hood, Texas. Current system, subsystem, and component designs are described and additional studies which support selection among significant design alternatives are presented. Overall system requirements which form the system design basis are presented. These include program objectives; performance and output load requirements; industrial, statutory, and regulatory standards; and site interface requirements. Material in this section will continue to be issued separately in the Systems Requirements Document and maintained current through revision throughout future phases of the project. Overall system design and detailedmore » subsystem design descriptions are provided. Consideration of operation and maintenance is reflected in discussion of each subsystem design as well as in an integrated overall discussion. Included are the solar collector subsystem; the thermal storage subsystem, the power conversion sybsystem (including electrical generation and distribution); the heating/cooling and domestic hot water subsystems; overall instrumentation and control; and the STES building and physical plant. The design of several subsystems has progressed beyond the preliminary stage; descriptions for such subsystems are therefore provided in more detail than others to provide complete documentation of the work performed. In some cases, preliminary design parameters require specific verificaton in the definitive design phase and are identified in the text. Subsystem descriptions will continue to be issued and revised separately to maintain accuracy during future phases of the project. (WHK)« less

  17. Writing Simple Sentences and Descriptive Paragraphs: Effects of an Intervention on Adolescents with Writing Difficulties

    ERIC Educational Resources Information Center

    Datchuk, Shawn M.

    2016-01-01

    The present study investigated the effects of a multicomponent intervention on the writing behavior of adolescents with writing difficulties. A single-case design consisting of a combination of multiple-probe design across participants and pre-post test was used. Four participants completed two intervention phases: (a) sentence instruction and…

  18. Evidence-informed health policy 4 – Case descriptions of organizations that support the use of research evidence

    PubMed Central

    Lavis, John N; Moynihan, Ray; Oxman, Andrew D; Paulsen, Elizabeth J

    2008-01-01

    Background Previous efforts to produce case descriptions have typically not focused on the organizations that produce research evidence and support its use. External evaluations of such organizations have typically not been analyzed as a group to identify the lessons that have emerged across multiple evaluations. Case descriptions offer the potential for capturing the views and experiences of many individuals who are familiar with an organization, including staff, advocates, and critics. Methods We purposively sampled a subgroup of organizations from among those that participated in the second (interview) phase of the study and (once) from among other organizations with which we were familiar. We developed and pilot-tested a case description data collection protocol, and conducted site visits that included both interviews and documentary analyses. Themes were identified from among responses to semi-structured questions using a constant comparative method of analysis. We produced both a brief (one to two pages) written description and a video documentary for each case. Results We conducted 51 interviews as part of the eight site visits. Two organizational strengths were repeatedly cited by individuals participating in the site visits: use of an evidence-based approach (which was identified as being very time-consuming) and existence of a strong relationship between researchers and policymakers (which can be challenged by conflicts of interest). Two organizational weaknesses – a lack of resources and the presence of conflicts of interest – were repeatedly cited by individuals participating in the site visits. Participants offered two main suggestions for the World Health Organization (and other international organizations and networks): 1) mobilize one or more of government support, financial resources, and the participation of both policymakers and researchers; and 2) create knowledge-related global public goods. Conclusion The findings from our case descriptions, the first of their kind, intersect in interesting ways with the messages arising from two systematic reviews of the factors that increase the prospects for research use in policymaking. Strong relationships between researchers and policymakers bodes well given such interactions appear to increase the prospects for research use. The time-consuming nature of an evidence-based approach, on the other hand, suggests the need for more efficient production processes that are 'quick and clean enough.' Our case descriptions and accompanying video documentaries provide a rich description of organizations supporting the use of research evidence, which can be drawn upon by those establishing or leading similar organizations, particularly in low- and middle-income countries. PMID:19091110

  19. Joint estimation of phase and phase diffusion for quantum metrology.

    PubMed

    Vidrighin, Mihai D; Donati, Gaia; Genoni, Marco G; Jin, Xian-Min; Kolthammer, W Steven; Kim, M S; Datta, Animesh; Barbieri, Marco; Walmsley, Ian A

    2014-04-14

    Phase estimation, at the heart of many quantum metrology and communication schemes, can be strongly affected by noise, whose amplitude may not be known, or might be subject to drift. Here we investigate the joint estimation of a phase shift and the amplitude of phase diffusion at the quantum limit. For several relevant instances, this multiparameter estimation problem can be effectively reshaped as a two-dimensional Hilbert space model, encompassing the description of an interferometer phase probed with relevant quantum states--split single-photons, coherent states or N00N states. For these cases, we obtain a trade-off bound on the statistical variances for the joint estimation of phase and phase diffusion, as well as optimum measurement schemes. We use this bound to quantify the effectiveness of an actual experimental set-up for joint parameter estimation for polarimetry. We conclude by discussing the form of the trade-off relations for more general states and measurements.

  20. The pdf approach to turbulent polydispersed two-phase flows

    NASA Astrophysics Data System (ADS)

    Minier, Jean-Pierre; Peirano, Eric

    2001-10-01

    The purpose of this paper is to develop a probabilistic approach to turbulent polydispersed two-phase flows. The two-phase flows considered are composed of a continuous phase, which is a turbulent fluid, and a dispersed phase, which represents an ensemble of discrete particles (solid particles, droplets or bubbles). Gathering the difficulties of turbulent flows and of particle motion, the challenge is to work out a general modelling approach that meets three requirements: to treat accurately the physically relevant phenomena, to provide enough information to address issues of complex physics (combustion, polydispersed particle flows, …) and to remain tractable for general non-homogeneous flows. The present probabilistic approach models the statistical dynamics of the system and consists in simulating the joint probability density function (pdf) of a number of fluid and discrete particle properties. A new point is that both the fluid and the particles are included in the pdf description. The derivation of the joint pdf model for the fluid and for the discrete particles is worked out in several steps. The mathematical properties of stochastic processes are first recalled. The various hierarchies of pdf descriptions are detailed and the physical principles that are used in the construction of the models are explained. The Lagrangian one-particle probabilistic description is developed first for the fluid alone, then for the discrete particles and finally for the joint fluid and particle turbulent systems. In the case of the probabilistic description for the fluid alone or for the discrete particles alone, numerical computations are presented and discussed to illustrate how the method works in practice and the kind of information that can be extracted from it. Comments on the current modelling state and propositions for future investigations which try to link the present work with other ideas in physics are made at the end of the paper.

  1. Chronic health needs immediately after natural disasters in middle-income countries: the case of the 2008 Sichuan, China earthquake.

    PubMed

    Chan, Emily Y Y; Kim, Jackie

    2011-04-01

    Few studies have focused on chronic health needs immediately after natural disasters in middle-income countries. This study examines chronic medical needs during the acute phase after the 2008 Sichuan earthquake. A descriptive, cross-sectional study was conducted in an emergency triage clinic in Sichuan, China. Information on physical, social, and public health preparedness was collected in predesigned templates. Descriptive and Pearson's χ association analyses were conducted. One hundred and eighty-two evacuees were received at the triage site. Of these, 54% required trauma treatment and 77% of evacuated patients who required care had underlying chronic medical conditions. Tetanus immunizations and the possession of chronic health medication were low, particularly among older patients. Chronic health needs constituted a significant proportion of emergency care during the acute phase in the study population. Effective post-disaster assistance requires attention to demographic and epidemiological population profiles.

  2. Transition from Poissonian to Gaussian-orthogonal-ensemble level statistics in a modified Artin's billiard

    NASA Astrophysics Data System (ADS)

    Csordás, A.; Graham, R.; Szépfalusy, P.; Vattay, G.

    1994-01-01

    One wall of an Artin's billiard on the Poincaré half-plane is replaced by a one-parameter (cp) family of nongeodetic walls. A brief description of the classical phase space of this system is given. In the quantum domain, the continuous and gradual transition from the Poisson-like to Gaussian-orthogonal-ensemble (GOE) level statistics due to the small perturbations breaking the symmetry responsible for the ``arithmetic chaos'' at cp=1 is studied. Another GOE-->Poisson transition due to the mixed phase space for large perturbations is also investigated. A satisfactory description of the intermediate level statistics by the Brody distribution was found in both cases. The study supports the existence of a scaling region around cp=1. A finite-size scaling relation for the Brody parameter as a function of 1-cp and the number of levels considered can be established.

  3. New systematic methodology for incorporating dynamic heat transfer modelling in multi-phase biochemical reactors.

    PubMed

    Fernández-Arévalo, T; Lizarralde, I; Grau, P; Ayesa, E

    2014-09-01

    This paper presents a new modelling methodology for dynamically predicting the heat produced or consumed in the transformations of any biological reactor using Hess's law. Starting from a complete description of model components stoichiometry and formation enthalpies, the proposed modelling methodology has integrated successfully the simultaneous calculation of both the conventional mass balances and the enthalpy change of reaction in an expandable multi-phase matrix structure, which facilitates a detailed prediction of the main heat fluxes in the biochemical reactors. The methodology has been implemented in a plant-wide modelling methodology in order to facilitate the dynamic description of mass and heat throughout the plant. After validation with literature data, as illustrative examples of the capability of the methodology, two case studies have been described. In the first one, a predenitrification-nitrification dynamic process has been analysed, with the aim of demonstrating the easy integration of the methodology in any system. In the second case study, the simulation of a thermal model for an ATAD has shown the potential of the proposed methodology for analysing the effect of ventilation and influent characterization. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Geometry induced phase transitions in magnetic spherical shell

    NASA Astrophysics Data System (ADS)

    Sloika, Mykola I.; Sheka, Denis D.; Kravchuk, Volodymyr P.; Pylypovskyi, Oleksandr V.; Gaididei, Yuri

    2017-12-01

    Equilibrium magnetization states in spherical shells of a magnetically soft ferromagnet form two out-of-surface vortices with codirectionally magnetized vortex cores at the sphere poles: (i) a whirligig state with the in-surface magnetization oriented along parallels is typical for thick shells; (ii) a three dimensional onion state with the in-surface meridional direction of the magnetization is realized in thin shells. The geometry of spherical shell prohibits an existence of spatially homogeneous magnetization distribution, even in the case of small sample radii. By varying geometrical parameters a continuous phase transition between the whirligig and onion states takes place. The detailed analytical description of the phase diagram is well confirmed by micromagnetic simulations.

  5. Patient participation as dialogue: setting research agendas

    PubMed Central

    Abma, Tineke A.; Broerse, Jacqueline E. W.

    2010-01-01

    Abstract Background  Collaboration with patients in healthcare and medical research is an emerging development. We aimed to develop a methodology for health research agenda setting processes grounded in the notion of participation as dialogue. Methods  We conducted seven case studies between 2003 and 2007 to develop and validate a Dialogue Model for patient participation in health research agenda setting. The case studies related to spinal cord injury, neuromuscular diseases, renal failure, asthma/chronic obstructive pulmonary disease, burns, diabetes and intellectual disabilities. Results  The Dialogue Model is grounded in participatory and interactive approaches and has been adjusted on the basis of pilot work. It has six phases: exploration; consultation; prioritization; integration; programming; and implementation. These phases are discussed and illustrated with a case description of research agenda setting relating to burns. Conclusions  The dialogue model appeared relevant and feasible to structure the process of collaboration between stakeholders in several research agenda setting processes. The phase of consultation enables patients to develop their own voice and agenda, and prepares them for the broader collaboration with other stakeholder groups. Challenges include the stimulation of more permanent changes in research, and institutional transitions. PMID:20536537

  6. Phase dynamics of coupled oscillators reconstructed from data

    NASA Astrophysics Data System (ADS)

    Rosenblum, Michael; Kralemann, Bjoern; Pikovsky, Arkady

    2013-03-01

    We present a technique for invariant reconstruction of the phase dynamics equations for coupled oscillators from data. The invariant description is achieved by means of a transformation of phase estimates (protophases) obtained from general scalar observables to genuine phases. Staring from the bivariate data, we obtain the coupling functions in terms of these phases. We discuss the importance of the protophase-to-phase transformation for characterization of strength and directionality of interaction. To illustrate the technique we analyse the cardio-respiratory interaction on healthy humans. Our invariant approach is confirmed by high similarity of the coupling functions obtained from different observables of the cardiac system. Next, we generalize the technique to cover the case of small networks of coupled periodic units. We use the partial norms of the reconstructed coupling functions to quantify directed coupling between the oscillators. We illustrate the method by different network motifs for three coupled oscillators. We also discuss nonlinear effects in coupling.

  7. The Development of the Unified Protocol for the Transdiagnostic Treatment of Emotional Disorders: A Case Study

    PubMed Central

    Boisseau, Christina L.; Farchione, Todd J.; Fairholme, Christopher P.; Ellard, Kristen K.; Barlow, David H.

    2013-01-01

    A detailed description of treatment utilizing the Unified Protocol (UP), a transdiagnostic emotion-focused cognitive-behavioral treatment, is presented using a clinical case example treated during the most current phase of an ongoing randomized controlled trial of the UP. The implementation of the UP in its current, modular version is illustrated. A working case conceptualization is presented from the perspective of the UP drawing from theory and research that underlies current transdiagnostic approaches to treatment and consistent with recent dimensional classification proposals (Brown & Barlow, in press). Treatment is illustrated module-by-module describing how the principles of the UP were applied in the presented case. PMID:23997572

  8. A Descriptive Case Study of Appreciative Inquiry as an Approach to Strategic Planning for Special Education in a Public School

    ERIC Educational Resources Information Center

    Ruhlman, Paul L., Jr.

    2014-01-01

    This study's purpose was to describe appreciative inquiry (AI) as an approach to strategic planning for special education in a public school. The study investigated four research questions. How do plans for special education emerge as participants engage in the four phases of AI during strategic planning for the future of special education in a…

  9. Cluster formation in nuclear reactions from mean-field inhomogeneities

    NASA Astrophysics Data System (ADS)

    Napolitani, Paolo; Colonna, Maria; Mancini-Terracciano, Carlo

    2018-05-01

    Perturbing fluids of neutrons and protons (nuclear matter) may lead, as the most catastrophic effect, to the rearrangement of the fluid into clusters of nucleons. A similar process may occur in a single atomic nucleus undergoing a violent perturbation, like in heavy-ion collisions tracked in particle accelerators at around 30 to 50 MeV per nucleon: in this conditions, after the initial collision shock, the nucleus expands and then clusterises into several smaller nuclear fragments. Microscopically, when violent perturbation are applied to nuclear matter, a process of clusterisation arises from the combination of several fluctuation modes of large-amplitude where neutrons and protons may oscillate in phase or out of phase. The imposed perturbation leads to conditions of instability, the wavelengths which are the most amplified have sizes comparable to small atomic nuclei. We found that these conditions, explored in heavy-ion collisions, correspond to the splitting of a nucleus into fragments ranging from Oxygen to Neon in a time interval shorter than one zeptosecond (10 ‑ 21s). From the out-of-phase oscillations of neutrons and protons another property arises, the smaller fragments belonging to a more volatile phase get more neutron enriched: in the heavy-ion collision case this process, called distillation, reflects in the isotopic distributions of the fragments. The resulting dynamical description of heavy-ion collisions is an improvement with respect to more usual statistical approaches, based on the equilibrium assumption. It allows in fact to characterise also the very fast early stages of the collision process which are out of equilibrium. Such dynamical description is the core of the Boltzmann-Langevin One Body (BLOB) model, which in its latest development unifies in a common approach the description of fluctuations in nuclear matter, and a predictive description of the disintegration of nuclei into nuclear fragments. After a theoretical introduction, a few practical examples will be illustrated. This paper resumes the extended analysis of fluctuations in nuclear matter of ref. [2] and briefly reviews applications to heavy-ion collisions.

  10. Bright squeezed vacuum in a nonlinear interferometer: Frequency and temporal Schmidt-mode description

    NASA Astrophysics Data System (ADS)

    Sharapova, P. R.; Tikhonova, O. V.; Lemieux, S.; Boyd, R. W.; Chekhova, M. V.

    2018-05-01

    Control over the spectral properties of the bright squeezed vacuum (BSV), a highly multimode nonclassical macroscopic state of light that can be generated through high-gain parametric down conversion, is crucial for many applications. In particular, in several recent experiments BSV is generated in a strongly pumped SU(1,1) interferometer to achieve phase supersensitivity, perform broadband homodyne detection, or tailor the frequency spectrum of squeezed light. In this work, we present an analytical approach to the theoretical description of BSV in the frequency domain based on the Bloch-Messiah reduction and the Schmidt-mode formalism. As a special case we consider a strongly pumped SU(1,1) interferometer. We show that different moments of the radiation at its output depend on the phase, dispersion, and the parametric gain in a nontrivial way, thereby providing additional insights on the capabilities of nonlinear interferometers. In particular, a dramatic change in the spectrum occurs as the parametric gain increases.

  11. On the Time Evolution of Gamma-Ray Burst Pulses: A Self-Consistent Description.

    PubMed

    Ryde; Svensson

    2000-01-20

    For the first time, the consequences of combining two well-established empirical relations that describe different aspects of the spectral evolution of observed gamma-ray burst (GRB) pulses are explored. These empirical relations are (1) the hardness-intensity correlation and (2) the hardness-photon fluence correlation. From these we find a self-consistent, quantitative, and compact description for the temporal evolution of pulse decay phases within a GRB light curve. In particular, we show that in the case in which the two empirical relations are both valid, the instantaneous photon flux (intensity) must behave as 1&solm0;&parl0;1+t&solm0;tau&parr0;, where tau is a time constant that can be expressed in terms of the parameters of the two empirical relations. The time evolution is fully defined by two initial constants and two parameters. We study a complete sample of 83 bright GRB pulses observed by the Compton Gamma-Ray Observatory and identify a major subgroup of GRB pulses ( approximately 45%) which satisfy the spectral-temporal behavior described above. In particular, the decay phase follows a reciprocal law in time. It is unclear what physics causes such a decay phase.

  12. The risk of a second diagnostic window with 4th generation HIV assays: Two cases.

    PubMed

    Niederhauser, C; Ströhle, A; Stolz, M; Müller, F; Tinguely, C

    2009-08-01

    Despite the improved sensitivity of the 4th generation combined antigen/antibody HIV assays, detection of HIV in the early phase of an infection may still be ineffective. Description of two cases that highlight the existence of the "second diagnostic window phase" observed with commonly used sensitive 4th generation HIV assays. Samples were screened with different 4th generation HIV assays. HIV infection was confirmed with an HIV I/II antibody assay, a HIV-1 p24 antigen assay, the INNO-LIA HIV I/II Score Line immunoassay and HIV-1 PCR. In both investigated cases, the limitations of the 4th generation HIV assays within the second diagnostic window were apparent. The overall sensitivity of the commercial 4th generation HIV assays is currently higher than the 3rd generation HIV assays. Nevertheless, the rare occurrence of a second diagnostic window with 4th generation HIV assays strongly suggests that the following up testing algorithms need to be adjusted accordingly.

  13. Variance of foot biomechanical parameters across age groups for the elderly people in Romania

    NASA Astrophysics Data System (ADS)

    Deselnicu, D. C.; Vasilescu, A. M.; Militaru, G.

    2017-10-01

    The paper presents the results of a fieldwork study conducted in order to analyze major causal factors that influence the foot deformities and pathologies of elderly women in Romania. The study has an exploratory and descriptive nature and uses quantitative methodology. The sample consisted of 100 elderly women from Romania, ranging from 55 to over 75 years of age. The collected data was analyzed on multiple dimensions using a statistic analysis software program. The analysis of variance demonstrated significant differences across age groups in terms of several biomechanical parameters such as travel speed, toe off phase and support phase in the case of elderly women.

  14. Development of a Knowledge Base of Ti-Alloys From First-Principles and Thermodynamic Modeling

    NASA Astrophysics Data System (ADS)

    Marker, Cassie

    An aging population with an active lifestyle requires the development of better load-bearing implants, which have high levels of biocompatibility and a low elastic modulus. Titanium alloys, in the body centered cubic phase, are great implant candidates, due to their mechanical properties and biocompatibility. The present work aims at investigating the thermodynamic and elastic properties of bcc Tialloys, using the integrated first-principles based on Density Functional Theory (DFT) and the CALculation of PHAse Diagrams (CALPHAD) method. The use of integrated first-principles calculations based on DFT and CALPHAD modeling has greatly reduced the need for trial and error metallurgy, which is ineffective and costly. The phase stability of Ti-alloys has been shown to greatly affect their elastic properties. Traditionally, CALPHAD modeling has been used to predict the equilibrium phase formation, but in the case of Ti-alloys, predicting the formation of two metastable phases o and alpha" is of great importance as these phases also drastically effect the elastic properties. To build a knowledge base of Ti-alloys, for biomedical load-bearing implants, the Ti-Mo-Nb-Sn-Ta-Zr system was studied because of the biocompatibility and the bcc stabilizing effects of some of the elements. With the focus on bcc Ti-rich alloys, a database of thermodynamic descriptions of each phase for the pure elements, binary and Ti-rich ternary alloys was developed in the present work. Previous thermodynamic descriptions for the pure elements were adopted from the widely used SGTE database for global compatibility. The previous binary and ternary models from the literature were evaluated for accuracy and new thermodynamic descriptions were developed when necessary. The models were evaluated using available experimental data, as well as the enthalpy of formation of the bcc phase obtained from first-principles calculations based on DFT. The thermodynamic descriptions were combined into a database ensuring that the sublattice models are compatible with each other. For subsystems, such as the Sn-Ta system, where no thermodynamic description had been evaluated and minimal experimental data was available, first-principles calculations based on DFT were used. The Sn-Ta system has two intermetallic phases, TaSn2 and Ta3Sn, with three solution phases: bcc, body centered tetragonal (bct) and diamond. First-principles calculations were completed on the intermetallic and solution phases. Special quasirandom structures (SQS) were used to obtain information about the solution phases across the entire composition range. The Debye-Gruneisen approach, as well as the quasiharmonic phonon method, were used to obtain the finite-temperature data. Results from the first-principles calculations and experiments were used to complete the thermodynamic description. The resulting phase diagram reproduced the first-principles calculations and experimental data accurately. In order to determine the effect of alloying on the elastic properties, first-principles calculations based on DFT were systematically done on the pure elements, five Ti-X binary systems and Ti-X-Y ternary systems (X ≠ Y = Mo, Nb, Sn, Ta Zr) in the bcc phase. The first-principles calculations predicted the single crystal elastic stiffness constants cij 's. Correspondingly, the polycrystalline aggregate properties were also estimated from the cij's, including bulk modulus B, shear modulus G and Young's modulus E. The calculated results showed good agreement with experimental results. The CALPHAD method was then adapted to assist in the database development of the elastic properties as a function of composition. On average, the database predicted the elastic properties of higher order Ti-alloys within 5 GPa of the experimental results. Finally, the formation of the metastable phases, o and alpha" was studied in the Ti-Ta and Ti-Nb systems. The formation energy of these phases, calculated from first-principles at 0 K, showed that the phases have similar formation energies to the bcc and hcp phases. Inelastic neutron scattering was completed on four different Ti-Nb compositions to study the entropy of the phases as well as the transformations occurring when the phases form and the phase fractions. Ongoing work is being done to use the experimental information to introduce thermodynamic descriptions for these two phases in the Ti-Nb system in order to be able to predict the formation and phase fractions. DFT based first-principles were used to predict the effect these phases have on the elastic properties and a rule of mixtures was used to determine the elastic properties of multi-phase alloys. The results were compared with experiments and showed that if the ongoing modeling can predict the phase fraction, the elastic database can accurately predict the elastic properties of the o and alpha" phases. This thesis provides a knowledge base of the thermodynamic and elastic properties of Ti-alloys from computational thermodynamics. The databases created will impact research activities on Ti-alloys and specifically efforts focused on Ti-alloys for biomedical applications.

  15. The Influence of Educational Experience on the Development of Cognitive Skills as Measured in Formal Tests and Experiments: A Case Study from the Mexican States of Yucatan and Quintana Roo. Final Report.

    ERIC Educational Resources Information Center

    Sharp, Donald W.; Cole, Michael

    The major purpose of the research reported was to assess whether developmental changes in performance on standard psychological tests may be more a reflection of educational experience than maturation or traditional socialization practices. The investigation was reported in three phases: 1) description of the general and specific experimental…

  16. Hypersonic ramjet experiment project. Phase 1: Computer program description, ramjet and scramjet cycle performance

    NASA Technical Reports Server (NTRS)

    Jackson, R. J.; Wang, T. T.

    1974-01-01

    A computer program was developed to describe the performance of ramjet and scramjet cycles. The program performs one dimensional calculations of the equilibrium, real-gas internal flow properties of the engine. The program can be used for the following: (1) preliminary design calculation and (2) design analysis of internal flow properties corresponding to stipulated flow areas. Only the combustion of hydrogen in air is considered in this case.

  17. Experimental and Modeling Study of the Burning of an Ethanol Droplet in Microgravity

    NASA Technical Reports Server (NTRS)

    Kazakov, Andrei; Conley, Jordan; Dryer, Frederick L.; Ferkul, Paul (Technical Monitor)

    2000-01-01

    The microgravity ethanol droplet combustion experiments were performed aboard the STS-94/MSL-1 Shuttle mission within the Fiber-Supported Droplet Combustion-2 (FSDC-2) program. The burning histories and flame standoffs for pure ethanol and ethanol/water droplets were obtained from the images recorded with two 8 mm videocameras. The obtained results show that average gasification rate is related to the initial droplet size in a manner similar to n-alkanes and methanol and consistent with the results of Hara and Kumagai and the data taken recently in the NASA-Lewis 2.2 s droptower. A transient, moving finite-element chemically reacting flow model applied previously to sphero-symmetric combustion of methanol, methanol/water, n-alkane, and n-alkane binary mixture droplets was adopted for the problem of ethanol droplet combustion. The model includes detailed description of gas-phase reaction chemistry and transport, a simplified description of liquid phase transport, and non-luminous radiative heat transfer. Gas-phase chemistry was described with the detailed reaction mechanism of Norton and Dryer, which consists of 142 reversible elementary reactions of 33 species. Another recently published reaction mechanism of high-temperature ethanol oxidation was also considered. The model predictions were found to compare favorably with the experimental data. The model analysis also indicates that water condensation in the case of ethanol has smaller effect on average droplet gasification rate as compared with previously studied methanol cases. This effect is explained by non-ideal (azeotropic) behavior of binary ethanol-water mixtures. Further analysis of computational results and ethanol droplet radiative extinction behavior will be discussed.

  18. Pandemic influenza A (H1N1) in Saudi Arabia: description of the first one hundred cases.

    PubMed

    AlMazroa, Mohammad A; Memish, Ziad A; AlWadey, Ali M

    2010-01-01

    In April 2009, the World Health Organization (WHO) declared pandemic influenza A (H1N1) "public health emergency of international concern". On June 11, 2009, WHO raised the pandemic alert level to phase 6, indicating a global pandemic. By December 2009, more than 208 countries and territories had reported swine flu cases. The descriptive epidemiology of the first reported 100 cases of this virus in Saudi Arabia are summarized in this report. Data were collected from 1 June to 3 July, 2009 using a predesigned questionnaire. Questionnaires were filled by Field Epidemiology Training Program residents. Data for the first 100 complete cases of confirmed pandemic influenza A (H1N1) were compiled and analyzed. The age of reported cases was in the range of 1 to 56 years. The highest percentage of cases was in the age group of 20 to 30 years followed by the age group of 1 to 10 years. Females represented 55% of the cases; imported cases represented 47%, 58% of whom had come via the King Khaled Airport. The most common nationalities most were from Saudi Arabia and the Philippines. The main symptoms were fever (56%), cough (54%), and sore throat and the number of cases was seen to peak from the 27 to 29 June. Pandemic influenza A (H1N1) is still a threat to Saudi Arabia. Thus, comprehensive and effective measures for surveillance and prevention of the disease are needed to control its spread.

  19. Defects at grain boundaries: A coarse-grained, three-dimensional description by the amplitude expansion of the phase-field crystal model

    NASA Astrophysics Data System (ADS)

    Salvalaglio, Marco; Backofen, Rainer; Elder, K. R.; Voigt, Axel

    2018-05-01

    We address a three-dimensional, coarse-grained description of dislocation networks at grain boundaries between rotated crystals. The so-called amplitude expansion of the phase-field crystal model is exploited with the aid of finite element method calculations. This approach allows for the description of microscopic features, such as dislocations, while simultaneously being able to describe length scales that are orders of magnitude larger than the lattice spacing. Moreover, it allows for the direct description of extended defects by means of a scalar order parameter. The versatility of this framework is shown by considering both fcc and bcc lattice symmetries and different rotation axes. First, the specific case of planar, twist grain boundaries is illustrated. The details of the method are reported and the consistency of the results with literature is discussed. Then, the dislocation networks forming at the interface between a spherical, rotated crystal embedded in an unrotated crystalline structure, are shown. Although explicitly accounting for dislocations which lead to an anisotropic shrinkage of the rotated grain, the extension of the spherical grain boundary is found to decrease linearly over time in agreement with the classical theory of grain growth and recent atomistic investigations. It is shown that the results obtained for a system with bcc symmetry agree very well with existing results, validating the methodology. Furthermore, fully original results are shown for fcc lattice symmetry, revealing the generality of the reported observations.

  20. Description of Adsorption in Liquid Chromatography under Nonideal Conditions.

    PubMed

    Ortner, Franziska; Ruppli, Chantal; Mazzotti, Marco

    2018-05-15

    A thermodynamically consistent description of binary adsorption in reversed-phase chromatography is presented, accounting for thermodynamic nonidealities in the liquid and adsorbed phases. The investigated system involves the adsorbent Zorbax 300SB-C18, as well as phenetole and 4- tert-butylphenol as solutes and methanol and water as inert components forming the eluent. The description is based on adsorption isotherms, which are a function of the liquid-phase activities, to account for nonidealities in the liquid phase. Liquid-phase activities are calculated with a UNIQUAC model established in this work, based on experimental phase equilibrium data. The binary interaction in the adsorbed phase is described by the adsorbed solution theory, assuming an ideal (ideal adsorbed solution theory) or real (real adsorbed solution theory) adsorbed phase. Implementation of the established adsorption model in a chromatographic code achieves a quantitative description of experimental elution profiles, with feed compositions exploiting the entire miscible region, and involving a broad range of different eluent compositions (methanol/water). The quantitative agreement of the model and experimental data serves as a confirmation of the underlying physical (thermodynamic) concepts and of their applicability to a broad range of operating conditions.

  1. Description of intraoral pressures on sub-palatal space in young adult patients with normal occlusion.

    PubMed

    Fuentes, Ramón; Engelke, Wilfried; Flores, Tania; Navarro, Pablo; Borie, Eduardo; Curiqueo, Aldo; Salamanca, Carlos

    2015-01-01

    Under normal conditions, the oral cavity presents a perfect system of equilibrium between teeth, soft tissues and tongue. The equilibrium of soft tissues forms a closed capsular matrix, generating differences with the atmospheric environment. This difference is known as intraoral pressure. Negative intraoral pressure is fundamental to the stabilization of the soft palate and tongue, reducing neuromuscular activity for the permeability of the respiratory tract. Thus, the aim of this study was to describe the variations of intraoral pressure of the sub-palatal space (SPS) under different physiological conditions and biofunctional phases. A case series was conducted with 20 individuals aged between 18 and 25. The intraoral pressures were measured through a system of cannulae connected to a digital pressure meter in the SPS during seven biofunctional phases. Descriptive statistics were used based on the mean and standard deviation. The data recorded pressure variations under physiological conditions, reaching 65 mbar as the intraoral peak in forced inspiration. In the swallowing phase, peaks reached -91.9 mbar. No pressure variations were recorded in terms of atmospheric changes with the mouth open and semi-open. The data obtained during the swallowing and forced inspiration phases indicated forced lingual activity. In the swallowing phase, the adequate position of the tongue creates negative intraoral pressure, which represents a fundamental mechanism for the physical stabilization of the soft palate. This information could contribute to subsequent research into the treatment of primary roncopathies.

  2. Rényi entropies characterizing the shape and the extension of the phase space representation of quantum wave functions in disordered systems.

    PubMed

    Varga, Imre; Pipek, János

    2003-08-01

    We discuss some properties of the generalized entropies, called Rényi entropies, and their application to the case of continuous distributions. In particular, it is shown that these measures of complexity can be divergent; however, their differences are free from these divergences, thus enabling them to be good candidates for the description of the extension and the shape of continuous distributions. We apply this formalism to the projection of wave functions onto the coherent state basis, i.e., to the Husimi representation. We also show how the localization properties of the Husimi distribution on average can be reconstructed from its marginal distributions that are calculated in position and momentum space in the case when the phase space has no structure, i.e., no classical limit can be defined. Numerical simulations on a one-dimensional disordered system corroborate our expectations.

  3. Stochastic and Boltzmann-like models for behavioral changes, and their relation to game theory

    NASA Astrophysics Data System (ADS)

    Helbing, Dirk

    1993-03-01

    In the last decade, stochastic models have shown to be very useful for quantitative modelling of social processes. Here, a configurational master equation for the description of behavioral changes by pair interactions of individuals is developed. Three kinds of social pair interactions are distinguished: Avoidance processes, compromising processes, and imitative processes. Computational results are presented for a special case of imitative processes: the competition of two equivalent strategies. They show a phase transition that describes the self-organization of a behavioral convention. This phase transition is further analyzed by examining the equations for the most probable behavioral distribution, which are Boltzmann-like equations. Special cases of Boltzmann-like equations do not obey the H-theorem and have oscillatory or even chaotic solutions. A suitable Taylor approximation leads to the so-called game dynamical equations (also known as selection-mutation equations in the theory of evolution).

  4. Phase-and-amplitude recovery from a single phase-contrast image using partially spatially coherent x-ray radiation

    NASA Astrophysics Data System (ADS)

    Beltran, Mario A.; Paganin, David M.; Pelliccia, Daniele

    2018-05-01

    A simple method of phase-and-amplitude extraction is derived that corrects for image blurring induced by partially spatially coherent incident illumination using only a single intensity image as input. The method is based on Fresnel diffraction theory for the case of high Fresnel number, merged with the space-frequency description formalism used to quantify partially coherent fields and assumes the object under study is composed of a single-material. A priori knowledge of the object’s complex refractive index and information obtained by characterizing the spatial coherence of the source is required. The algorithm was applied to propagation-based phase-contrast data measured with a laboratory-based micro-focus x-ray source. The blurring due to the finite spatial extent of the source is embedded within the algorithm as a simple correction term to the so-called Paganin algorithm and is also numerically stable in the presence of noise.

  5. Evolution of the clinical and epidemiological knowledge about Chagas disease 90 years after its discovery.

    PubMed

    Prata, A

    1999-01-01

    Three different periods may be considered in the evolution of knowledge about the clinical and epidemiological aspects of Chagas disease since its discovery: (a) early period concerning the studies carried out by Carlos Chagas in Lassance with the collaboration of other investigators of the Manguinhos School. At that time the disease was described and the parasite, transmitters and reservoirs were studied. The coexistence of endemic goiter in the same region generated some confusion about the clinical forms of the disease; (b) second period involving uncertainty and the description of isolated cases, which lasted until the 1940 decade. Many acute cases were described during this period and the disease was recognized in many Latin American countries. Particularly important were the studies of the Argentine Mission of Regional Pathology Studies, which culminated with the description of the Romaña sign in the 1930 decade, facilitating the diagnosis of the early phase of the disease. However, the chronic phase, which was the most important, continued to be difficult to recognize; (c) period of consolidation of knowledge and recognition of the importance of Chagas disease. Studies conducted by Laranja, Dias and Nóbrega in Bambuí updated the description of Chagas heart disease made by Carlos Chagas and Eurico Villela. From then on, the disease was more easily recognized, especially with the emphasis on the use of a serologic diagnosis; (d) period of enlargement of knowledges on the disease. The studies on denervation conducted in Ribeirão Preto by Fritz Köberle starting in the 1950 decade led to a better understanding of the relations between Chagas disease and megaesophagus and other visceral megas detected in endemic areas.

  6. Phase Field Modeling of Directional Fracture in Anisotropic Polycrystals

    DTIC Science & Technology

    2015-02-01

    include [35–37]. The phase field description of fracture should be con- trasted with continuum damage mechanics descriptions such as [38,39] that do not...ARL-RP-0518 ● FEBRUARY 2015 US Army Research Laboratory Phase Field Modeling of Directional Fracture in Anisotropic Polycrystals...0518 ● FEBRUARY 2015 US Army Research Laboratory Phase Field Modeling of Directional Fracture in Anisotropic Polycrystals by JD Clayton

  7. Phase Control in Nonlinear Systems

    NASA Astrophysics Data System (ADS)

    Zambrano, Samuel; Seoane, Jesús M.; Mariño, Inés P.; Sanjuán, Miguel A. F.; Meucci, Riccardo

    The following sections are included: * Introduction * Phase Control of Chaos * Description of the model * Numerical exploration of phase control of chaos * Experimental evidence of phase control of chaos * Phase Control of Intermittency in Dynamical Systems * Crisis-induced intermittency and its control * Experimental setup and implementation of the phase control scheme * Phase control of the laser in the pre-crisis regime * Phase control of the intermittency after the crisis * Phase control of the intermittency in the quadratic map * Phase Control of Escapes in Open Dynamical Systems * Control of open dynamical systems * Model description * Numerical simulations and heuristic arguments * Experimental implementation in an electronic circuit * Conclusions and Discussions * Acknowledgments * References

  8. Identification of characteristics and frequent scenarios of single-vehicle rollover crashes during pre-ballistic phase; part 1 - A descriptive study.

    PubMed

    Kim, Taewung; Bose, Dipan; Foster, Jon; Bollapragada, Varun; Crandall, Jeff R; Clauser, Mark; Kerrigan, Jason R

    2017-10-01

    This study aimed to identify common patterns of pre-ballistic vehicle kinematics and roadway characteristics of real-world rollover crashes. Rollover crashes that were enrolled in the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) between the years 2000 and 2010 were analyzed. A descriptive analysis was performed to understand the characteristics of the pre-ballistic phase. Also, a frequency based pattern analysis was performed using a selection of NASS-CDS variables describing the pre-ballistic vehicle kinematics and roadway characteristics to rank common pathways of rollover crashes. Most case vehicles departed the road due to a loss of control/traction (LOC) (61%). The road departure with LOC was found to be 13.4 times more likely to occur with slippery road conditions compared to dry conditions. The vehicle was typically laterally skidding with yawing prior to a rollover (66%). Most case vehicles tripped over (82%) mostly at roadside/median (69%). The tripping force was applied to the wheels/tires (82%) from the ground (79%). The combination of these six most frequent attributes resulted in the most common scenario, which accounted for 26% of the entire cases. Large proportion of road departure with LOC (61%) implies electronic stability control (ESC) systems being an effective countermeasure for preventing single-vehicle rollover crashes. Furthermore, the correlation between the road departure with LOC and the reduced friction limit suggests the necessity of the performance evaluation of ESC under compromised road surface condition. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Quantum oscillations in a biaxial pair density wave state.

    PubMed

    Norman, M R; Davis, J C Séamus

    2018-05-22

    There has been growing speculation that a pair density wave state is a key component of the phenomenology of the pseudogap phase in the cuprates. Recently, direct evidence for such a state has emerged from an analysis of scanning tunneling microscopy data in halos around the vortex cores. By extrapolation, these vortex halos would then overlap at a magnetic-field scale where quantum oscillations have been observed. Here, we show that a biaxial pair density wave state gives a unique description of the quantum oscillation data, bolstering the case that the pseudogap phase in the cuprates may be a pair density wave state. Copyright © 2018 the Author(s). Published by PNAS.

  10. FNAS/summer faculty fellowship research continuation program. Task 6: Integrated model development for liquid fueled rocket propulsion systems. Task 9: Aspects of model-based rocket engine condition monitoring and control

    NASA Technical Reports Server (NTRS)

    Santi, L. Michael; Helmicki, Arthur J.

    1993-01-01

    The objective of Phase I of this research effort was to develop an advanced mathematical-empirical model of SSME steady-state performance. Task 6 of Phase I is to develop component specific modification strategy for baseline case influence coefficient matrices. This report describes the background of SSME performance characteristics and provides a description of the control variable basis of three different gains models. The procedure used to establish influence coefficients for each of these three models is also described. Gains model analysis results are compared to Rocketdyne's power balance model (PBM).

  11. Selection of optimal complexity for ENSO-EMR model by minimum description length principle

    NASA Astrophysics Data System (ADS)

    Loskutov, E. M.; Mukhin, D.; Mukhina, A.; Gavrilov, A.; Kondrashov, D. A.; Feigin, A. M.

    2012-12-01

    One of the main problems arising in modeling of data taken from natural system is finding a phase space suitable for construction of the evolution operator model. Since we usually deal with strongly high-dimensional behavior, we are forced to construct a model working in some projection of system phase space corresponding to time scales of interest. Selection of optimal projection is non-trivial problem since there are many ways to reconstruct phase variables from given time series, especially in the case of a spatio-temporal data field. Actually, finding optimal projection is significant part of model selection, because, on the one hand, the transformation of data to some phase variables vector can be considered as a required component of the model. On the other hand, such an optimization of a phase space makes sense only in relation to the parametrization of the model we use, i.e. representation of evolution operator, so we should find an optimal structure of the model together with phase variables vector. In this paper we propose to use principle of minimal description length (Molkov et al., 2009) for selection models of optimal complexity. The proposed method is applied to optimization of Empirical Model Reduction (EMR) of ENSO phenomenon (Kravtsov et al. 2005, Kondrashov et. al., 2005). This model operates within a subset of leading EOFs constructed from spatio-temporal field of SST in Equatorial Pacific, and has a form of multi-level stochastic differential equations (SDE) with polynomial parameterization of the right-hand side. Optimal values for both the number of EOF, the order of polynomial and number of levels are estimated from the Equatorial Pacific SST dataset. References: Ya. Molkov, D. Mukhin, E. Loskutov, G. Fidelin and A. Feigin, Using the minimum description length principle for global reconstruction of dynamic systems from noisy time series, Phys. Rev. E, Vol. 80, P 046207, 2009 Kravtsov S, Kondrashov D, Ghil M, 2005: Multilevel regression modeling of nonlinear processes: Derivation and applications to climatic variability. J. Climate, 18 (21): 4404-4424. D. Kondrashov, S. Kravtsov, A. W. Robertson and M. Ghil, 2005. A hierarchy of data-based ENSO models. J. Climate, 18, 4425-4444.

  12. The Iron-Iron Carbide Phase Diagram: A Practical Guide to Some Descriptive Solid State Chemistry.

    ERIC Educational Resources Information Center

    Long, Gary J.; Leighly, H. P., Jr.

    1982-01-01

    Discusses the solid state chemistry of iron and steel in terms of the iron-iron carbide phase diagram. Suggests that this is an excellent way of introducing the phase diagram (equilibrium diagram) to undergraduate students while at the same time introducing the descriptive solid state chemistry of iron and steel. (Author/JN)

  13. Nematic fluctuations balancing the zoo of phases in half-filled quantum Hall systems

    NASA Astrophysics Data System (ADS)

    Mesaros, Andrej; Lawler, Michael J.; Kim, Eun-Ah

    2017-03-01

    Half-filled Landau levels form a zoo of strongly correlated phases. These include non-Fermi-liquids (NFLs), fractional quantum Hall (FQH) states, nematic phases, and FQH nematic phases. This diversity begs the following question: what keeps the balance between the seemingly unrelated phases? The answer is elusive because the Halperin-Lee-Read description that offers a natural departure point is inherently strongly coupled. However, the observed nematic phases suggest that nematic fluctuations play an important role. To study this possibility, we apply a recently formulated controlled double-expansion approach in large-N composite fermion flavors and small ɛ nonanalytic bosonic action to the case with both gauge and nematic boson fluctuations. In the vicinity of a nematic quantum critical line, we find that depending on the amount of screening of the gauge- and nematic-mediated interactions controlled by ɛ 's, the renormalization-group flow points to all four mentioned correlated phases. When pairing preempts the nematic phase, NFL behavior is possible at temperatures above the pairing transition. We conclude by discussing measurements at low tilt angles, which could reveal the stabilization of the FQH phase by nematic fluctuations.

  14. Interpretation of architecture changes by combined use of historical sources, IR Termography and GPR: the study case of San Francesco convent near Montella (AV), Italy

    NASA Astrophysics Data System (ADS)

    Geraldi, Edoardo; Loperte, Antonio; Dolce, Carmen

    2010-05-01

    In order to reconstruct architectural changes during the centuries often we are forced to trust merely on the evidences of documentary and iconographical sources which could sometimes supply the description of the monument or of a specifically building phase. Such approach does not solve all the questions related to the interpretation of historical data (graphics, descriptions) useful for finding previous configurations of the building. The historical building structure and shape, as they appear at the present are often the final result of a stratification of different phases deeply connected with artistic and technological features of the age during which the building has been designed and realized. Stylistic features, building techniques and functional aspects change in time leaving often written traces in archive sources such as on the building masonry texture (sometimes hidden by plaster) or under the floor. In such situation the Non Destructive Testing investigations by means of infrared thermography and GPR could be useful to characterize masonry, to survey inhomogeneities in the masonry as well as to detect buried walls belongings to ancient building phases. This paper deals with the emblematic study case of San Francisco convent near Montella in Southern Italy. Its complex vicissitudes experienced in last centuries have been the reason of radical transformations of the church and its surrounding buildings. Historical research provided important information on structural interventions and planimetric transformations carried out between the 17th and 18th century. Such data have been correlated with the results obtained by infrared thermography surveys on plastered facades of the convent and GPR profiles carried out under the stone paved floor of the church and cloister, thus improving the knowledge of historical building phases of the monument. The integrated use of building analysis techniques based on NDT techniques together with historical and archaeological records show the enormous potential of the use of this interdisciplinary approach.

  15. Poincaré analysis of wave motion in ultrarelativistic electron-ion plasmas.

    PubMed

    Lehmann, G; Spatschek, K H

    2011-03-01

    Based on a relativistic Maxwell-fluid description, the existence of ultrarelativistic laser-induced periodic waves in an electron-ion plasma is investigated. Within a one-dimensional propagation geometry nonlinear coupling of the electromagnetic and electrostatic components occurs that makes the fourth-order problem nonintegrable. A Hamiltonian description is derived, and the manifolds of periodic solutions are studied by Poincaré section plots. The influence of ion motion is investigated in different intensity regimes. For ultrarelativistic laser intensities the phase-space structures change significantly compared to the weakly relativistic case. Ion motion becomes very important such that finally electron-ion plasmas in the far-ultrarelativistic regime behave similarly to electron-positron plasmas. The characteristic new types of periodic solutions of the system are identified and discussed.

  16. Some dipole shower studies

    NASA Astrophysics Data System (ADS)

    Cabouat, Baptiste; Sjöstrand, Torbjörn

    2018-03-01

    Parton showers have become a standard component in the description of high-energy collisions. Nowadays most final-state ones are of the dipole character, wherein a pair of partons branches into three, with energy and momentum preserved inside this subsystem. For initial-state showers a dipole picture is also possible and commonly used, but the older global-recoil strategy remains a valid alternative, wherein larger groups of partons share the energy-momentum preservation task. In this article we introduce and implement a dipole picture also for initial-state radiation in Pythia, and compare with the existing global-recoil one, and with data. For the case of Deeply Inelastic Scattering we can directly compare with matrix element expressions and show that the dipole picture gives a very good description over the whole phase space, at least for the first branching.

  17. Index cost estimate based BIM method - Computational example for sports fields

    NASA Astrophysics Data System (ADS)

    Zima, Krzysztof

    2017-07-01

    The paper presents an example ofcost estimation in the early phase of the project. The fragment of relative database containing solution, descriptions, geometry of construction object and unit cost of sports facilities was shown. The Index Cost Estimate Based BIM method calculationswith use of Case Based Reasoning were presented, too. The article presentslocal and global similarity measurement and example of BIM based quantity takeoff process. The outcome of cost calculations based on CBR method was presented as a final result of calculations.

  18. A description of phases with induced hybridisation at finite temperatures

    NASA Astrophysics Data System (ADS)

    Golosov, D. I.

    2018-05-01

    In an extended Falicov-Kimball model, an excitonic insulator phase can be stabilised at zero temperature. With increasing temperature, the excitonic order parameter (interaction-induced hybridisation on-site, characterised by the absolute value and phase) eventually becomes disordered, which involves fluctuations of both its phase and (at higher T) its absolute value. In order to build an adequate mean field description, it is important to clarify the nature of degrees of freedom associated with the phase and absolute value of the induced hybridisation, and the corresponding phase space volume. We show that a possible description is provided by the SU(4) parametrisation on-site. In principle, this allows to describe both the lower-temperature regime where phase fluctuations destroy the long-range order, and the higher temperature crossover corresponding to a decrease of absolute value of the hybridisation relative to the fluctuations level. This picture is also expected to be relevant in other contexts, including the Kondo lattice model.

  19. Case Management in Primary Care for Frequent Users of Health Care Services: A Mixed Methods Study.

    PubMed

    Hudon, Catherine; Chouinard, Maud-Christine; Dubois, Marie-France; Roberge, Pasquale; Loignon, Christine; Tchouaket, Éric; Lambert, Mireille; Hudon, Émilie; Diadiou, Fatoumata; Bouliane, Danielle

    2018-05-01

    This study aimed to evaluate the effects of the V1SAGES case management intervention (Vulnerable Patients in Primary Care: Nurse Case Management and Self-management Support) for frequent users of health care services with chronic disease and complex care needs on psychological distress and patient activation. We used a 2-phase sequential mixed methods design. The first phase was a pragmatic randomized controlled trial with intention-to-treat analysis that measured the effects of the intervention compared with usual care on psychological distress and patient activation before and after 6 months. The second phase had a qualitative descriptive design and entailed thematic analysis of in-depth interviews (25 patients, 6 case management nurses, 9 health managers) and focus groups (8 patients' spouses, 21 family physicians) to understand stakeholders' perceived effects of the intervention on patients. A total of 247 patients were randomized into the intervention group (n = 126) or the control group (n = 121). Compared with usual care, the intervention reduced psychological distress (odds ratio = 0.43; 95% CI, 0.19-0.95, P = .04), but did not have any significant effect on patient activation ( P = .43). Qualitative results suggested that patients and their spouses benefitted from the case management intervention, gaining a sense of security, and stakeholders noted better patient self-management of health. Together, our study's quantitative and qualitative results suggest that case management reduces psychological distress, making patients and caregivers feel more secure, whereas impact on self-management is unclear. Case management is a promising avenue to improve outcomes among frequent users of health care with complex needs. © 2018 Annals of Family Medicine, Inc.

  20. Measles resurgence following a nationwide measles vaccination campaign in Nigeria, 2005-2008.

    PubMed

    Weldegebriel, Goitom G; Gasasira, Alex; Harvey, Pauline; Masresha, Balcha; Goodson, James L; Pate, Muhammad A; Abanida, Emmanuel; Chevez, Ana

    2011-07-01

    From 1990 through 2008, routine immunization coverage of measles vaccine in Nigeria ranged from 35% to 70%. Nigeria conducted a nationwide measles vaccination campaign in 2 phases during 2005-2006 that targeted children aged 9 months to 14 years; in 2008, a nationwide follow-up campaign that targeted children aged 9 months to 4 years was conducted in 2 phases. Despite these efforts, measles cases continued to occur. This is a descriptive study that reviewed the measles immunization coverage data from administrative, World Health Organization, United Nations Children's Fund, survey, and supplemental immunization activities data. Measles surveillance data were analyzed from case-based surveillance reports. Confirmed measles cases increased from 383 in 2006 to 2542 in 2007 and to 9510 in 2008. Of the confirmed cases in 2008, 717 (30%) occurred in children <2 years of age, 1145 (48%) in children 2-4 years of age, and 354 (14%) were in children 5-14 years of age. In 2008, the measles case fatality rate was 1.2%. Suboptimal routine coverage and the wide interval between the catch-up and follow-up campaigns likely led to an accumulation of children susceptible to measles. © The Author 2011. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved.

  1. Phases, phase equilibria, and phase rules in low-dimensional systems

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

    Frolov, T., E-mail: timfrol@berkeley.edu; Mishin, Y., E-mail: ymishin@gmu.edu

    2015-07-28

    We present a unified approach to thermodynamic description of one, two, and three dimensional phases and phase transformations among them. The approach is based on a rigorous definition of a phase applicable to thermodynamic systems of any dimensionality. Within this approach, the same thermodynamic formalism can be applied for the description of phase transformations in bulk systems, interfaces, and line defects separating interface phases. For both lines and interfaces, we rigorously derive an adsorption equation, the phase coexistence equations, and other thermodynamic relations expressed in terms of generalized line and interface excess quantities. As a generalization of the Gibbs phasemore » rule for bulk phases, we derive phase rules for lines and interfaces and predict the maximum number of phases than may coexist in systems of the respective dimensionality.« less

  2. Consequences of insecurity in emergency telephone consultations: an experimental study in medical students.

    PubMed

    Barth, J; Ahrens, R; Schaufelberger, M

    2014-01-01

    Handling emergency telephone consultations (ETCs) is a challenging and very important task for doctors. The aims of the study were to document insecurity in medical students during ETCs and to identify the reasons for that insecurity. We hypothesised that insecurity is associated with advising more urgent action (e.g. advice to call for an ambulance) in ETCs. We used ETCs with simulated patients (SPs), with each student randomly allocated two of four possible cases. After the training, 137 students reported on any insecurity that they had in the various ETC phases. We analysed the reasons for insecurity using descriptive statistics. The association between the students' advice that urgent action was needed and their insecurity was analysed with Spearman rank correlation. Overall, 95% of the students felt insecure in at least one phase of their ETC. History taking was the phase in which students felt most insecure (63.1%), followed by the phase of analysing the information given by the patient (44.9%). Perceived insecurity was associated with more urgent advice in one case scenario (abdominal pain; correlation r = 0.46; p <0.01). The other two cases (child with fever; chest pain) also had a positive, but not statistically significant, correlation trend (p <0.12; p <0.08). Insecurity is highly prevalent among medical students in their ETC decision-making. ETC training in medical schools, with a focus on structured history taking and formulating discriminating questions, might help decrease insecurity in ETCs. Medical education should also teach management of insecurity.

  3. Labour management and Obstetric outcomes among pregnant women admitted in latent phase compared to active phase of labour at Bugando Medical Centre in Tanzania

    PubMed Central

    2014-01-01

    Background Interventions given to women admitted in latent or active phase of labor may influence the outcomes of labor and ameliorate complications which can affect the mother and fetus. Labour management, maternal and fetal outcomes among low risk women presenting both in latent phase and active phase of labour in Tanzania have not recently been explored. Methods This was a descriptive cross-sectional study. It was done from February to April 2013. Case notes were collected serially until the sample size was reached. A structured checklist was used to extract data. Data was analyzed using SPSS version 17. A p < 0.05 was considered significant at 95% confidence interval. Results Five hundred case notes of low risk pregnant women were collected, half of each presented in latent phase and active phase of labour. Key interventions including augmentation with oxytocin, artificial rupture of membranes and caesarean section were significantly higher in the latent phase group than the active phase group 84(33.6%) versus 52(20.8%) p < 0.05; 96(38.6%) versus 56(22.4%) p < 0.05 and 87(34.8%) versus 60(24.0%) p < 0.05 respectively. Spontaneous vertex delivery was higher among pregnant women admitted initially in active phase than in latent phase groups 180(72.0%), versus 153(61.2%) p > 0.01). There were more women in the active phase group who sustained genital tract tear and postpartum haemorrhage than in the latent phase group 101(18.6%), versus 38(15.6%) p < 0.01 and 46(18.4%), versus 17(6.6%) p < 0.05 respectively. Conclusions Pregnant women admitted at BMC in latent phase of labour are subjected to more obstetric interventions than those admitted in the active phase. There is need to produce guidelines on management of women admitted in latent phase of labour at BMC to reduce the risk of unnecessary interventions. PMID:24521301

  4. Labour management and Obstetric outcomes among pregnant women admitted in latent phase compared to active phase of labour at Bugando Medical Centre in Tanzania.

    PubMed

    Chuma, Clotrida; Kihunrwa, Albert; Matovelo, Dismas; Mahendeka, Marietha

    2014-02-12

    Interventions given to women admitted in latent or active phase of labor may influence the outcomes of labor and ameliorate complications which can affect the mother and fetus. Labour management, maternal and fetal outcomes among low risk women presenting both in latent phase and active phase of labour in Tanzania have not recently been explored. This was a descriptive cross-sectional study. It was done from February to April 2013. Case notes were collected serially until the sample size was reached. A structured checklist was used to extract data. Data was analyzed using SPSS version 17. A p < 0.05 was considered significant at 95% confidence interval. Five hundred case notes of low risk pregnant women were collected, half of each presented in latent phase and active phase of labour. Key interventions including augmentation with oxytocin, artificial rupture of membranes and caesarean section were significantly higher in the latent phase group than the active phase group 84(33.6%) versus 52(20.8%) p < 0.05; 96(38.6%) versus 56(22.4%) p < 0.05 and 87(34.8%) versus 60(24.0%) p < 0.05 respectively. Spontaneous vertex delivery was higher among pregnant women admitted initially in active phase than in latent phase groups 180(72.0%), versus 153(61.2%) p > 0.01). There were more women in the active phase group who sustained genital tract tear and postpartum haemorrhage than in the latent phase group 101(18.6%), versus 38(15.6%) p < 0.01 and 46(18.4%), versus 17(6.6%) p < 0.05 respectively. Pregnant women admitted at BMC in latent phase of labour are subjected to more obstetric interventions than those admitted in the active phase. There is need to produce guidelines on management of women admitted in latent phase of labour at BMC to reduce the risk of unnecessary interventions.

  5. Thermodynamic Modelling of Phase Transformation in a Multi-Component System

    NASA Astrophysics Data System (ADS)

    Vala, J.

    2007-09-01

    Diffusion in multi-component alloys can be characterized by the vacancy mechanism for substitutional components, by the existence of sources and sinks for vacancies and by the motion of atoms of interstitial components. The description of diffusive and massive phase transformation of a multi-component system is based on the thermodynamic extremal principle by Onsager; the finite thickness of the interface between both phases is respected. The resulting system of partial differential equations of evolution with integral terms for unknown mole fractions (and additional variables in case of non-ideal sources and sinks for vacancies), can be analyzed using the method of lines and the finite difference technique (or, alternatively, the finite element one) together with the semi-analytic and numerical integration formulae and with certain iteration procedure, making use of the spectral properties of linear operators. The original software code for the numerical evaluation of solutions of such systems, written in MATLAB, offers a chance to simulate various real processes of diffusional phase transformation. Some results for the (nearly) steady-state real processes in substitutional alloys have been published yet. The aim of this paper is to demonstrate that the same approach can handle both substitutional and interstitial components even in case of a general system of evolution.

  6. Collective phase description of oscillatory convection

    NASA Astrophysics Data System (ADS)

    Kawamura, Yoji; Nakao, Hiroya

    2013-12-01

    We formulate a theory for the collective phase description of oscillatory convection in Hele-Shaw cells. It enables us to describe the dynamics of the oscillatory convection by a single degree of freedom which we call the collective phase. The theory can be considered as a phase reduction method for limit-cycle solutions in infinite-dimensional dynamical systems, namely, stable time-periodic solutions to partial differential equations, representing the oscillatory convection. We derive the phase sensitivity function, which quantifies the phase response of the oscillatory convection to weak perturbations applied at each spatial point, and analyze the phase synchronization between two weakly coupled Hele-Shaw cells exhibiting oscillatory convection on the basis of the derived phase equations.

  7. A Multiphase Validation of Atlas-Based Automatic and Semiautomatic Segmentation Strategies for Prostate MRI

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

    Martin, Spencer; Rodrigues, George, E-mail: george.rodrigues@lhsc.on.ca; Department of Epidemiology/Biostatistics, University of Western Ontario, London

    2013-01-01

    Purpose: To perform a rigorous technological assessment and statistical validation of a software technology for anatomic delineations of the prostate on MRI datasets. Methods and Materials: A 3-phase validation strategy was used. Phase I consisted of anatomic atlas building using 100 prostate cancer MRI data sets to provide training data sets for the segmentation algorithms. In phase II, 2 experts contoured 15 new MRI prostate cancer cases using 3 approaches (manual, N points, and region of interest). In phase III, 5 new physicians with variable MRI prostate contouring experience segmented the same 15 phase II datasets using 3 approaches: manual,more » N points with no editing, and full autosegmentation with user editing allowed. Statistical analyses for time and accuracy (using Dice similarity coefficient) endpoints used traditional descriptive statistics, analysis of variance, analysis of covariance, and pooled Student t test. Results: In phase I, average (SD) total and per slice contouring time for the 2 physicians was 228 (75), 17 (3.5), 209 (65), and 15 seconds (3.9), respectively. In phase II, statistically significant differences in physician contouring time were observed based on physician, type of contouring, and case sequence. The N points strategy resulted in superior segmentation accuracy when initial autosegmented contours were compared with final contours. In phase III, statistically significant differences in contouring time were observed based on physician, type of contouring, and case sequence again. The average relative timesaving for N points and autosegmentation were 49% and 27%, respectively, compared with manual contouring. The N points and autosegmentation strategies resulted in average Dice values of 0.89 and 0.88, respectively. Pre- and postedited autosegmented contours demonstrated a higher average Dice similarity coefficient of 0.94. Conclusion: The software provided robust contours with minimal editing required. Observed time savings were seen for all physicians irrespective of experience level and baseline manual contouring speed.« less

  8. Thermodynamic description of multicomponent nickel-base superalloys containing aluminum, chromium, ruthenium and platinum: A computational thermodynamic approach coupled with experiments

    NASA Astrophysics Data System (ADS)

    Zhu, Jun

    Ru and Pt are candidate additional component for improving the high temperature properties of Ni-base superalloys. A thermodynamic description of the Ni-Al-Cr-Ru-Pt system, serving as an essential knowledge base for better alloy design and processing control, was developed in the present study by means of thermodynamic modeling coupled with experimental investigations of phase equilibria. To deal with the order/disorder transition occurring in the Ni-base superalloys, a physical sound model, Cluster/Site Approximation (CSA) was used to describe the fcc phases. The CSA offers computational advantages, without loss of accuracy, over the Cluster Variation Method (CVM) in the calculation of multicomponent phase diagrams. It has been successfully applied to fcc phases in calculating technologically important Ni-Al-Cr phase diagrams. Our effort in this study focused on the two key ternary systems: Ni-Al-Ru and Ni-Al-Pt. The CSA calculated Ni-Al-Ru ternary phase diagrams are in good agreement with the experimental results in the literature and from the current study. A thermodynamic description of quaternary Ni-Al-Cr-Ru was obtained based on the descriptions of the lower order systems and the calculated results agree with experimental data available in literature and in the current study. The Ni-Al-Pt system was thermodynamically modeled based on the limited experimental data available in the literature and obtained from the current study. With the help of the preliminary description, a number of alloy compositions were selected for further investigation. The information obtained was used to improve the current modeling. A thermodynamic description of the Ni-Al-Cr-Pt quaternary was then obtained via extrapolation from its constituent lower order systems. The thermodynamic description for Ni-base superalloy containing Al, Cr, Ru and Pt was obtained via extrapolation. It is believed to be reliable and useful to guide the alloy design and further experimental investigation.

  9. Workshop on Applications of Phase Diagrams in Metallurgy and Ceramics

    NASA Technical Reports Server (NTRS)

    Bennett, L. H.; Carter, G. C.

    1977-01-01

    A workshop was held to assess the current national and international status of phase diagram determinations and evaluations for alloys, ceramics, and semiconductors; to determine the needs and priorities, especially technological, for phase diagram determinations and evaluations; and to estimate the resources being used and potentially available for phase diagram evaluation. Highlights of the workshop, description of a new poster board design used in the poster sessions, lists of attendees and demonstrations, the program, and descriptions of the presentations are included.

  10. Phononic heat transport in nanomechanical structures: steady-state and pumping

    NASA Astrophysics Data System (ADS)

    Sena-Junior, Marcone I.; Lima, Leandro R. F.; Lewenkopf, Caio H.

    2017-10-01

    We study the heat transport due to phonons in nanomechanical structures using a phase space representation of non-equilibrium Green’s functions. This representation accounts for the atomic degrees of freedom making it particularly suited for the description of small (molecular) junctions systems. We rigorously show that for the steady state limit our formalism correctly recovers the heuristic Landauer-like heat conductance for a quantum coherent molecular system coupled to thermal reservoirs. We find general expressions for the non-stationary heat current due to an external periodic drive. In both cases we discuss the quantum thermodynamic properties of the systems. We apply our formalism to the case of a diatomic molecular junction.

  11. Group theoretical formulation of free fall and projectile motion

    NASA Astrophysics Data System (ADS)

    Düztaş, Koray

    2018-07-01

    In this work we formulate the group theoretical description of free fall and projectile motion. We show that the kinematic equations for constant acceleration form a one parameter group acting on a phase space. We define the group elements ϕ t by their action on the points in the phase space. We also generalize this approach to projectile motion. We evaluate the group orbits regarding their relations to the physical orbits of particles and unphysical solutions. We note that the group theoretical formulation does not apply to more general cases involving a time-dependent acceleration. This method improves our understanding of the constant acceleration problem with its global approach. It is especially beneficial for students who want to pursue a career in theoretical physics.

  12. On the role of self-adjointness in the continuum formulation of topological quantum phases

    NASA Astrophysics Data System (ADS)

    Tanhayi Ahari, Mostafa; Ortiz, Gerardo; Seradjeh, Babak

    2016-11-01

    Topological quantum phases of matter are characterized by an intimate relationship between the Hamiltonian dynamics away from the edges and the appearance of bound states localized at the edges of the system. Elucidating this correspondence in the continuum formulation of topological phases, even in the simplest case of a one-dimensional system, touches upon fundamental concepts and methods in quantum mechanics that are not commonly discussed in textbooks, in particular the self-adjoint extensions of a Hermitian operator. We show how such topological bound states can be derived in a prototypical one-dimensional system. Along the way, we provide a pedagogical exposition of the self-adjoint extension method as well as the role of symmetries in correctly formulating the continuum, field-theory description of topological matter with boundaries. Moreover, we show that self-adjoint extensions can be characterized generally in terms of a conserved local current associated with the self-adjoint operator.

  13. The physics of quantum materials

    NASA Astrophysics Data System (ADS)

    Keimer, B.; Moore, J. E.

    2017-11-01

    The physical description of all materials is rooted in quantum mechanics, which describes how atoms bond and electrons interact at a fundamental level. Although these quantum effects can in many cases be approximated by a classical description at the macroscopic level, in recent years there has been growing interest in material systems where quantum effects remain manifest over a wider range of energy and length scales. Such quantum materials include superconductors, graphene, topological insulators, Weyl semimetals, quantum spin liquids, and spin ices. Many of them derive their properties from reduced dimensionality, in particular from confinement of electrons to two-dimensional sheets. Moreover, they tend to be materials in which electrons cannot be considered as independent particles but interact strongly and give rise to collective excitations known as quasiparticles. In all cases, however, quantum-mechanical effects fundamentally alter properties of the material. This Review surveys the electronic properties of quantum materials through the prism of the electron wavefunction, and examines how its entanglement and topology give rise to a rich variety of quantum states and phases; these are less classically describable than conventional ordered states also driven by quantum mechanics, such as ferromagnetism.

  14. Asthma in changing environments - chances and challenges of international research collaborations between South America and Europe - study protocol and description of the data acquisition of a case-control-study

    PubMed Central

    2010-01-01

    Background Asthma in children is an emerging public health problem in South America. So far, research in this part of the world is limited. This paper presents the methodology and description of the data acquisition of an asthma case-control study conducted in the Central South of Chile. Methods/Design A hospital-based case-control study about asthma (188 cases, 294 controls) in children (6-15 years) was carried out in Valdivia, Chile between November 2008 and December 2009. Data on asthma risk factors were collected by computer-assisted personal interview using validated questions from e.g. ISAAC phase II. Data on household dust exposure (endotoxin, allergen analyses), skin prick tests to most common allergens, stool examinations for parasitic infection, and blood samples (total IgE, genetics) were collected. Additionally, 492 randomly chosen blood donors were recruited in order to assess allele frequencies in the population of Valdivia. Discussion Overall 1,173 participants were contacted. Response was 82% among cases and 65% among controls. Atopic sensitization was high (78% among cases, 47% among controls). Cases had a statistically significantly (p < .0001) increased self-reported 12-month prevalence of symptoms of rhinitis (82% vs. 51%) and wheeze (68% vs. 16%). The study is well placed to address current hypotheses about asthma and its correlates in the South American context. Results of this study might help develop novel, innovative and individualized prevention strategies in countries in transition with respect to the South American context. PMID:20718949

  15. A Multiphase Model for the Intracluster Medium

    NASA Technical Reports Server (NTRS)

    Nagai, Daisuke; Sulkanen, Martin E.; Evrard, August E.

    1999-01-01

    Constraints on the clustered mass density of the universe derived from the observed population mean intracluster gas fraction of x-ray clusters may be biased by reliance on a single-phase assumption for the thermodynamic structure of the intracluster medium (ICM). We propose a descriptive model for multiphase structure in which a spherically symmetric ICM contains isobaric density perturbations with a radially dependent variance. Fixing the x-ray emission and emission weighted temperature, we explore two independently observable signatures of the model in the parameter space. For bremsstrahlung dominated emission, the central Sunyaev-Zel'dovich (SZ) decrement in the multiphase case is increased over the single-phase case and multiphase x-ray spectra in the range 0.1-20 keV are flatter in the continuum and exhibit stronger low energy emission lines than their single-phase counterpart. We quantify these effects for a fiducial 10e8 K cluster and demonstrate how the combination of SZ and x-ray spectroscopy can be used to identify a preferred location in the plane of the model parameter space. From these parameters the correct value of mean intracluster gas fraction in the multiphase model results, allowing an unbiased estimate of clustered mass density to he recovered.

  16. Collective phase description of oscillatory convection

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

    Kawamura, Yoji, E-mail: ykawamura@jamstec.go.jp; Nakao, Hiroya

    We formulate a theory for the collective phase description of oscillatory convection in Hele-Shaw cells. It enables us to describe the dynamics of the oscillatory convection by a single degree of freedom which we call the collective phase. The theory can be considered as a phase reduction method for limit-cycle solutions in infinite-dimensional dynamical systems, namely, stable time-periodic solutions to partial differential equations, representing the oscillatory convection. We derive the phase sensitivity function, which quantifies the phase response of the oscillatory convection to weak perturbations applied at each spatial point, and analyze the phase synchronization between two weakly coupled Hele-Shawmore » cells exhibiting oscillatory convection on the basis of the derived phase equations.« less

  17. Turbulence in the Ott-Antonsen equation for arrays of coupled phase oscillators

    NASA Astrophysics Data System (ADS)

    Wolfrum, M.; Gurevich, S. V.; Omel'chenko, O. E.

    2016-02-01

    In this paper we study the transition to synchrony in an one-dimensional array of oscillators with non-local coupling. For its description in the continuum limit of a large number of phase oscillators, we use a corresponding Ott-Antonsen equation, which is an integro-differential equation for the evolution of the macroscopic profiles of the local mean field. Recently, it was reported that in the spatially extended case at the synchronisation threshold there appear partially coherent plane waves with different wave numbers, which are organised in the well-known Eckhaus scenario. In this paper, we show that for Kuramoto-Sakaguchi phase oscillators the phase lag parameter in the interaction function can induce a Benjamin-Feir-type instability of the partially coherent plane waves. The emerging collective macroscopic chaos appears as an intermediate stage between complete incoherence and stable partially coherent plane waves. We give an analytic treatment of the Benjamin-Feir instability and its onset in a codimension-two bifurcation in the Ott-Antonsen equation as well as a numerical study of the transition from phase turbulence to amplitude turbulence inside the Benjamin-Feir unstable region.

  18. First-principles calculations, experimental study, and thermodynamic modeling of the Al-Co-Cr system.

    PubMed

    Liu, Xuan L; Gheno, Thomas; Lindahl, Bonnie B; Lindwall, Greta; Gleeson, Brian; Liu, Zi-Kui

    2015-01-01

    The phase relations and thermodynamic properties of the condensed Al-Co-Cr ternary alloy system are investigated using first-principles calculations based on density functional theory (DFT) and phase-equilibria experiments that led to X-ray diffraction (XRD) and electron probe micro-analysis (EPMA) measurements. A thermodynamic description is developed by means of the calculations of phase diagrams (CALPHAD) method using experimental and computational data from the present work and the literature. Emphasis is placed on modeling the bcc-A2, B2, fcc-γ, and tetragonal-σ phases in the temperature range of 1173 to 1623 K. Liquid, bcc-A2 and fcc-γ phases are modeled using substitutional solution descriptions. First-principles special quasirandom structures (SQS) calculations predict a large bcc-A2 (disordered)/B2 (ordered) miscibility gap, in agreement with experiments. A partitioning model is then used for the A2/B2 phase to effectively describe the order-disorder transitions. The critically assessed thermodynamic description describes all phase equilibria data well. A2/B2 transitions are also shown to agree well with previous experimental findings.

  19. Job Aid Manuals for Phase I--ANALYZE of the Instructional Systems Development Model.

    ERIC Educational Resources Information Center

    Schulz, Russel E.; Farrell, Jean R.

    Designed to supplement the descriptive authoring flowcharts in a companion volume, this manual includes specific guidance, examples, and other information referred to in the flowcharts for the implementation of the first phase of the Instructional Systems Development Model (ISD). The introductory section includes definitions; descriptions of…

  20. Functional Description of Air Traffic Control

    DOT National Transportation Integrated Search

    1971-04-01

    The document contains a description of air traffic control in terms of generic operational functions. The functions are grouped by flight phase and by major system function (navigation, surveillance, control and communication). More detailed descript...

  1. Capillary Two-Phase Thermal Devices for Space Applications

    NASA Technical Reports Server (NTRS)

    Ku, Jentung

    2016-01-01

    This is the presentation file for an invited seminar for Department of Mechanical and Aerospace Engineering at the Case Western Reserve University. The seminar is scheduled for April 1, 2016.Description: This presentation will discuss operating principles and performance characteristics of heat pipes (HPs) and loop heat pipes (LHPs) and their application for spacecraft thermal control. Topics include: 1) HP operating principles; 2) HP performance characteristics; 3) LHP pressure profiles; 4) LHP operating temperature; 5) LHP operating temperature control; and 6) Examples of using HPs and LHPs on NASA flight projects.

  2. FBI fingerprint identification automation study: AIDS 3 evaluation report. Volume 5: Current system evaluation

    NASA Technical Reports Server (NTRS)

    Mulhall, B. D. L.

    1980-01-01

    The performance, costs, organization and other characteristics of both the manual system and AIDS 2 were used to establish a baseline case. The results of the evaluation are to be used to determine the feasibility of the AIDS 3 System, as well as provide a basis for ranking alternative systems during the second phase of the JPL study. The results of the study were tabulated by subject, scope and methods, providing a descriptive, quantitative and qualitative analysis of the current operating systems employed by the FBI Identification Division.

  3. EMC and power quality standards for 20-kHz power distribution

    NASA Technical Reports Server (NTRS)

    Hansen, Irving G.

    1987-01-01

    The Space Station Power Distribution System has been baselined as a sinusoidal single phase, 440 VRMS system. This system has certain unique characteristics directly affecting its application. In particular, existing systematic description and control documents were modified to reflect the high operating frequency. This paper will discuss amendments made on Mil STD 704 (Electrical Power Characteristics), and Mil STD 461-B (Electromagnetic Emission and Susceptibility Requirements for the Control of Electromagnetic Interference). In some cases these amendments reflect changes of several orders of magnitude. Implications and impacts of these changes are discussed.

  4. Frontiers in Fluid Mechanics: A Collection of Research Papers Written in Commemoration of the 65th Birthday of Stanley Corrsin.

    DTIC Science & Technology

    1985-04-30

    analogous fashion. If the flow variable lFtis taken at x and F 6(xi,t) > d , - 1, . n, n > 1 is required, various subsets of the flow domain atare obtained...discussed: non-premixed and premixed combustion. The chemistry of combustion in the gas phase involves complex systems of reaction steps with numerous...components. In order to keep the problem tractable, only a greatly simplified and global description of chemistry will be employed. In both cases V

  5. Phase space deformations in phantom cosmology

    NASA Astrophysics Data System (ADS)

    López, J. L.; Sabido, M.; Yee-Romero, C.

    2018-03-01

    We discuss the physical consequences of general phase space deformations on the minisuperspace of phantom cosmology. Based on the principle of physically equivalent descriptions in the deformed theory, we investigate for what values of the deformation parameters the arising descriptions are physically equivalent. We also construct and solve the quantum model and derive the semiclassical dynamics.

  6. Are Charge-State Distributions a Reliable Tool Describing Molecular Ensembles of Intrinsically Disordered Proteins by Native MS?

    NASA Astrophysics Data System (ADS)

    Natalello, Antonino; Santambrogio, Carlo; Grandori, Rita

    2017-01-01

    Native mass spectrometry (MS) has become a central tool of structural proteomics, but its applicability to the peculiar class of intrinsically disordered proteins (IDPs) is still object of debate. IDPs lack an ordered tridimensional structure and are characterized by high conformational plasticity. Since they represent valuable targets for cancer and neurodegeneration research, there is an urgent need of methodological advances for description of the conformational ensembles populated by these proteins in solution. However, structural rearrangements during electrospray-ionization (ESI) or after the transfer to the gas phase could affect data obtained by native ESI-MS. In particular, charge-state distributions (CSDs) are affected by protein conformation inside ESI droplets, while ion mobility (IM) reflects protein conformation in the gas phase. This review focuses on the available evidence relating IDP solution ensembles with CSDs, trying to summarize cases of apparent consistency or discrepancy. The protein-specificity of ionization patterns and their responses to ligands and buffer conditions suggests that CSDs are imprinted to protein structural features also in the case of IDPs. Nevertheless, it seems that these proteins are more easily affected by electrospray conditions, leading in some cases to rearrangements of the conformational ensembles.

  7. Are Charge-State Distributions a Reliable Tool Describing Molecular Ensembles of Intrinsically Disordered Proteins by Native MS?

    PubMed

    Natalello, Antonino; Santambrogio, Carlo; Grandori, Rita

    2017-01-01

    Native mass spectrometry (MS) has become a central tool of structural proteomics, but its applicability to the peculiar class of intrinsically disordered proteins (IDPs) is still object of debate. IDPs lack an ordered tridimensional structure and are characterized by high conformational plasticity. Since they represent valuable targets for cancer and neurodegeneration research, there is an urgent need of methodological advances for description of the conformational ensembles populated by these proteins in solution. However, structural rearrangements during electrospray-ionization (ESI) or after the transfer to the gas phase could affect data obtained by native ESI-MS. In particular, charge-state distributions (CSDs) are affected by protein conformation inside ESI droplets, while ion mobility (IM) reflects protein conformation in the gas phase. This review focuses on the available evidence relating IDP solution ensembles with CSDs, trying to summarize cases of apparent consistency or discrepancy. The protein-specificity of ionization patterns and their responses to ligands and buffer conditions suggests that CSDs are imprinted to protein structural features also in the case of IDPs. Nevertheless, it seems that these proteins are more easily affected by electrospray conditions, leading in some cases to rearrangements of the conformational ensembles. Graphical Abstract ᅟ.

  8. Medicare Program; Inpatient Rehabilitation Facility Prospective Payment System for Federal Fiscal Year 2016. Final rule.

    PubMed

    2015-08-06

    This final rule updates the prospective payment rates for inpatient rehabilitation facilities (IRFs) for federal fiscal year (FY) 2016 as required by the statute. As required by section 1886(j)(5) of the Act, this rule includes the classification and weighting factors for the IRF PPS's case-mix groups and a description of the methodologies and data used in computing the prospective payment rates for FY 2016. This final rule also finalizes policy changes, including the adoption of an IRF-specific market basket that reflects the cost structures of only IRF providers, a 1-year phase-in of the revised wage index changes, a 3-year phase-out of the rural adjustment for certain IRFs, and revisions and updates to the quality reporting program (QRP).

  9. Demonstration Advanced Avionics System (DAAS), Phase 1

    NASA Technical Reports Server (NTRS)

    Bailey, A. J.; Bailey, D. G.; Gaabo, R. J.; Lahn, T. G.; Larson, J. C.; Peterson, E. M.; Schuck, J. W.; Rodgers, D. L.; Wroblewski, K. A.

    1981-01-01

    Demonstration advanced anionics system (DAAS) function description, hardware description, operational evaluation, and failure mode and effects analysis (FMEA) are provided. Projected advanced avionics system (PAAS) description, reliability analysis, cost analysis, maintainability analysis, and modularity analysis are discussed.

  10. Analysis and IbM simulation of the stages in bacterial lag phase: basis for an updated definition.

    PubMed

    Prats, Clara; Giró, Antoni; Ferrer, Jordi; López, Daniel; Vives-Rego, Josep

    2008-05-07

    The lag phase is the initial phase of a culture that precedes exponential growth and occurs when the conditions of the culture medium differ from the pre-inoculation conditions. It is usually defined by means of cell density because the number of individuals remains approximately constant or slowly increases, and it is quantified with the lag parameter lambda. The lag phase has been studied through mathematical modelling and by means of specific experiments. In recent years, Individual-based Modelling (IbM) has provided helpful insights into lag phase studies. In this paper, the definition of lag phase is thoroughly examined. Evolution of the total biomass and the total number of bacteria during lag phase is tackled separately. The lag phase lasts until the culture reaches a maximum growth rate both in biomass and cell density. Once in the exponential phase, both rates are constant over time and equal to each other. Both evolutions are split into an initial phase and a transition phase, according to their growth rates. A population-level mathematical model is presented to describe the transitional phase in cell density. INDividual DIScrete SIMulation (INDISIM) is used to check the outcomes of this analysis. Simulations allow the separate study of the evolution of cell density and total biomass in a batch culture, they provide a depiction of different observed cases in lag evolution at the individual-cell level, and are used to test the population-level model. The results show that the geometrical lag parameter lambda is not appropriate as a universal definition for the lag phase. Moreover, the lag phase cannot be characterized by a single parameter. For the studied cases, the lag phases of both the total biomass and the population are required to fully characterize the evolution of bacterial cultures. The results presented prove once more that the lag phase is a complex process that requires a more complete definition. This will be possible only after the phenomena governing the population dynamics at an individual level of description, and occurring during the lag and exponential growth phases, are well understood.

  11. Surveillance for Q Fever Endocarditis in the United States, 1999-2015.

    PubMed

    Straily, Anne; Dahlgren, F Scott; Peterson, Amy; Paddock, Christopher D

    2017-11-13

    Q fever is a worldwide zoonosis caused by Coxiella burnetii. In some persons, particularly those with cardiac valve disease, infection with C. burnetii can cause a life-threatening infective endocarditis. There are few descriptive analyses of Q fever endocarditis in the United States. Q fever case report forms submitted during 1999-2015 were reviewed to identify reports describing endocarditis. Cases were categorized as confirmed or probable using criteria defined by the Council for State and Territorial Epidemiologists (CSTE). Demographic, laboratory, and clinical data were analyzed. Of 140 case report forms reporting endocarditis, 49 met the confirmed definition and 36 met the probable definition. Eighty-two percent were male and the median age was 57 years (range, 16-87 years). Sixty-seven patients (78.8%) were hospitalized, and 5 deaths (5.9%) were reported. Forty-five patients (52.9%) had a preexisting valvulopathy. Eight patients with endocarditis had phase I immunoglobulin G antibody titers >800 but did not meet the CSTE case definition for Q fever endocarditis. These data summarize a limited set of clinical and epidemiological features of Q fever endocarditis collected through passive surveillance in the United States. Some cases of apparent Q fever endocarditis could not be classified by CSTE laboratory criteria, suggesting that comparison of phase I and phase II titers could be reexamined as a surveillance criterion. Prospective analyses of culture-negative endocarditis are needed to better assess the clinical spectrum and magnitude of Q fever endocarditis in the United States. Published by Oxford University Press for the Infectious Diseases Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  12. Routine Sub-hepatic Drainage versus No Drainage after Laparoscopic Cholecystectomy: Open, Randomized, Clinical Trial.

    PubMed

    Shamim, Muhammad

    2013-02-01

    Surgeons are still following the old habit of routine subhepatic drainage following laparoscopic cholecystectomy (LC). This study aims to compare the outcome of subhepatic drainage with no drainage after LC. This prospective study was conducted in two phases. Phase I was open, randomized controlled trial (RCT), conducted in Civil Hospital Karachi, from August 2004 to June 2005. Phase II was descriptive case series, conducted in author's practice hospitals of Karachi, from July 2005 to December 2009. In phase I, 170 patients with chronic calculous cholecystitis underwent LC. Patients were divided into two groups, subhepatic drainage (group A: 79 patients) or no drainage (group B: 76 patients). The rest 15 patients were excluded either due to conversion or elective subhepatic drainage. In phase II, 218 consecutive patients were enrolled, who underwent LC with no subhepatic drainage. Duration of operation, character, and amount of drain fluid (if placed), postoperative ultrasound for subhepatic collection, postoperative chest X-ray for the measurement of subdiaphragmatic air, postoperative pain, postoperative nausea/vomiting, duration of hospital stay, and preoperative or postoperative complications were noted and analyzed. Duration of operation and hospital stay was slightly longer in group A patients (P values 0.002 and 0.029, respectively); postoperative pain perception, nausea/vomiting, and postoperative complications were nearly same in both groups (P value 0.064, 0.078, and 0.003, respectively). Subhepatic fluid collection was more in group A (P = 0.002), whereas subdiaphragmatic air collection was more in group B (P = 0.003). Phase II results were nearly similar to group B patients in phase I. Routine subhepatic drainage after LC is not necessary in uncomplicated cases.

  13. Limited utility of MRA for acute bowel ischemia after portal venous phase CT.

    PubMed

    Shetty, Anup S; Mellnick, Vincent M; Raptis, Constantine; Loch, Ronald; Owen, Joseph; Bhalla, Sanjeev

    2015-10-01

    Mesenteric ischemia and ischemic colitis are uncommon but potentially life-threatening causes of acute abdominal pain. Portal venous phase computed tomography (CT) is routinely ordered in the emergency room setting for abdominal pain, but subsequent MR angiography may be requested for additional evaluation of the mesenteric vasculature. We compare the concordance of CT and magnetic resonance angiography (MRA) for acute bowel ischemia. Thirty-two patients who underwent contrast-enhanced MRA for bowel ischemia after having undergone CT evaluation within the preceding 2 weeks were identified. A retrospective review of imaging, treatment history, surgical, and pathology reports was conducted. Two radiologists each reviewed the imaging studies in a blinded fashion. Ten cases of bowel ischemia were confirmed by endoscopy and/or surgical pathology. CT correctly identified bowel findings in all cases. Intraobserver agreement between CT and MRA for all vessels was 0.68 and 0.63, highest for the superior mesenteric artery. Interobserver agreement was 0.74 for MRA and 0.78 for CT. Vascular findings were only directly mentioned in 10 of 32 CT reports (and 7 of 10 cases with confirmed bowel ischemia). MRA only detected two additional or alternative diagnoses. Portal venous phase CT and MRA demonstrate a high degree of concordance for vascular evaluation. Reviewed CT examinations were sufficient to assess the patency of the mesenteric vasculature, but vascular findings were not reported in most cases. A direct description within the report may have obviated the request for further MR imaging. MRA adds little value after portal venous CT in assessing bowel ischemia.

  14. Space Station Freedom environmental control and life support system phase 3 simplified integrated test detailed report

    NASA Technical Reports Server (NTRS)

    Roberts, B. C.; Carrasquillo, R. L.; Dubiel, M. Y.; Ogle, K. Y.; Perry, J. L.; Whitley, K. M.

    1990-01-01

    A description of the phase 3 simplified integrated test (SIT) conducted at the Marshall Space Flight Center (MSFC) Core Module Integration Facility (CMIF) in 1989 is presented. This was the first test in the phase 3 series integrated environmental control and life support systems (ECLSS) tests. The basic goal of the SIT was to achieve full integration of the baseline air revitalization (AR) subsystems for Space Station Freedom. Included is a description of the SIT configuration, a performance analysis of each subsystem, results from air and water sampling, and a discussion of lessons learned from the test. Also included is a full description of the preprototype ECLSS hardware used in the test.

  15. Canine noninflammatory alopecia: a comprehensive evaluation of common and distinguishing histological characteristics.

    PubMed

    Müntener, Tabitha; Schuepbach-Regula, Gertraud; Frank, Linda; Rüfenacht, Silvia; Welle, Monika M

    2012-06-01

    Noninflammatory alopecia is a frequent problem in dogs, and the pathogenesis is still unclear. The objective of this study was a comparative histological description of skin biopsies from dogs with different alopecic disorders and control dogs matched for coat type, season and disease duration. Twenty-one cases of alopecia X in plush-coated dogs, 12 cases of recurrent flank alopecia, three cases of hyperestrogenism, 15 cases of hyperadrenocorticism, 12 cases of hypothyroidism and 12 cases of primary alopecic disorders of unknown cause were evaluated. The controls were biopsies from 38 dogs of different coat types. We evaluated five serial sections of each biopsy histologically and immunohistologically to compare the histological findings within the disease groups and with the control. All the dogs with hair cycle disorders had a significant increase in the number of hairless hair follicles, which we assigned to kenogen. In addition, dogs with alopecia X had the lowest percentage of anagen follicles and the highest percentage of telogen follicles. The marked increase in kenogen follicles is a strong indication that the induction of the new anagen phase is impaired in hair cycle disorders. The findings in dogs with alopecia X further suggest that premature catagen is also involved in the pathogenesis. Further work to investigate the stem cell compartment and possible initiating factors for the different cycle phases is required to elucidate the exact pathogenesis. © 2012 The Authors. Veterinary Dermatology. © 2012 ESVD and ACVD.

  16. System engineering toolbox for design-oriented engineers

    NASA Technical Reports Server (NTRS)

    Goldberg, B. E.; Everhart, K.; Stevens, R.; Babbitt, N., III; Clemens, P.; Stout, L.

    1994-01-01

    This system engineering toolbox is designed to provide tools and methodologies to the design-oriented systems engineer. A tool is defined as a set of procedures to accomplish a specific function. A methodology is defined as a collection of tools, rules, and postulates to accomplish a purpose. For each concept addressed in the toolbox, the following information is provided: (1) description, (2) application, (3) procedures, (4) examples, if practical, (5) advantages, (6) limitations, and (7) bibliography and/or references. The scope of the document includes concept development tools, system safety and reliability tools, design-related analytical tools, graphical data interpretation tools, a brief description of common statistical tools and methodologies, so-called total quality management tools, and trend analysis tools. Both relationship to project phase and primary functional usage of the tools are also delineated. The toolbox also includes a case study for illustrative purposes. Fifty-five tools are delineated in the text.

  17. A two-phase theory for non-Newtonian suspensions

    NASA Astrophysics Data System (ADS)

    Varsakelis, Christos

    In this talk, a continuum and thermodynamically consistent theory for macroscopic particles immersed in a non-Newtonian fluid is presented. According to the employed methodology, each phase of the mixture is treated as a thermodynamic system, endowed with its own set of thermodynamic and kinetic variables, and is required to separately satisfy the equations for the balance of mass, momentum and energy. As both constituents of the mixture are not simple fluids, additional degrees of freedom are introduced for the proper description of their thermodynamic state. A subsequent exploitation of the entropy inequality asserts that the accommodation of the complicated rheological characteristics of both phases requires a departure from a linear current-force relationship. For this reason, a subtle nonlinear representation of the stress tensors is employed. Importantly, the inclusion of additional degrees of freedom allows us to obtain a rate equation for the evolution of the volume fraction of the particulate phase. Following a delineation of the fundamentals of the proposed theory, the talk concludes with the presentation of some limiting cases that also serve as preliminary, sanity tests.

  18. Green Function Calculations of Properties for the Magnetocaloric Layered Structures Based Upon FeMnAsP

    NASA Astrophysics Data System (ADS)

    Schilling, Osvaldo F.

    2016-11-01

    The alternating Fe-Mn layered structures of the compounds FeMnAsxP1-x display properties which have been demonstrated experimentally as very promising as far as commercial applications of the magnetocaloric effect are concerned. However, the theoretical literature on this and other families of magnetocaloric compounds still adopts simple molecular-field models in the description of important statistical mechanical properties like the entropy variation that accompanies applied isothermal magnetic field cycling, as well as the temperature variation following adiabatic magnetic field cycles. In the present paper, a random phase approximation Green function theoretical treatment is applied to such structures. The advantages of such approach are well known since the details of the crystal structure are easily incorporated in the model, as well as a precise description of correlations between neighbor spins can be obtained. We focus on a simple one-exchange parameter Heisenberg model, and the observed first-order phase transitions are reproduced by the introduction of a biquadratic term in the Hamiltonian whose origin is related both to the magnetoelastic coupling with the phonon spectrum in these compounds as well as with the values of spins in the Fe and Mn ions. The calculations are compared with experimental magnetocaloric data for the FeMnAsxP1-x compounds. In particular, the magnetic field dependence for the entropy variation at the transition temperature predicted from the Landau theory of continuous phase transitions is reproduced even in the case of discontinuous transitions.

  19. Job Aids: Descriptive Authoring Flowcharts for Phase II--DESIGN of the Instructional Systems Development Model.

    ERIC Educational Resources Information Center

    Schulz, Russel E.; Farrell, Jean R.

    This resource guide for the use of job aids ("how-to-do-it" guidance) for activities identified in the second phase of the Instructional Systems Development Model (ISD) contains an introduction to the use of job aids, as well as descriptive authoring flowcharts for Blocks II.1 through II.4. The introduction includes definitions;…

  20. Job Aids: Descriptive Authoring Flowcharts for Phase I--ANALYZE of the Instructional Systems Development Model.

    ERIC Educational Resources Information Center

    Schulz, Russel E.; Farrell, Jean R.

    This resource guide for the use of job aids ("how-to-do-it" guidance) for activities identified in the first phase of the Instructional Systems Development Model (ISD) contains an introduction to the use of job aids, as well as descriptive authoring flowcharts for Blocks I.2 through I.5. The introduction includes definitions;…

  1. Job Aids: Descriptive Authoring Flowcharts for Phase III--DEVELOP of the Instructional Systems Development Model.

    ERIC Educational Resources Information Center

    Schulz, Russel E.; Farrell, Jean R.

    This resource guide for the use of job aids ("how-to-do-it" guidance) for activities identified in the third phase of the Instructional Systems Development Model (ISD) contains an introduction to the use of job aids, as well as descriptive authoring flowcharts for Blocks III.1 through III.5. The introduction includes definitions;…

  2. Supervised segmentation of phenotype descriptions for the human skeletal phenome using hybrid methods.

    PubMed

    Groza, Tudor; Hunter, Jane; Zankl, Andreas

    2012-10-15

    Over the course of the last few years there has been a significant amount of research performed on ontology-based formalization of phenotype descriptions. In order to fully capture the intrinsic value and knowledge expressed within them, we need to take advantage of their inner structure, which implicitly combines qualities and anatomical entities. The first step in this process is the segmentation of the phenotype descriptions into their atomic elements. We present a two-phase hybrid segmentation method that combines a series individual classifiers using different aggregation schemes (set operations and simple majority voting). The approach is tested on a corpus comprised of skeletal phenotype descriptions emerged from the Human Phenotype Ontology. Experimental results show that the best hybrid method achieves an F-Score of 97.05% in the first phase and F-Scores of 97.16% / 94.50% in the second phase. The performance of the initial segmentation of anatomical entities and qualities (phase I) is not affected by the presence / absence of external resources, such as domain dictionaries. From a generic perspective, hybrid methods may not always improve the segmentation accuracy as they are heavily dependent on the goal and data characteristics.

  3. Particle Interactions Mediated by Dynamical Networks: Assessment of Macroscopic Descriptions

    NASA Astrophysics Data System (ADS)

    Barré, J.; Carrillo, J. A.; Degond, P.; Peurichard, D.; Zatorska, E.

    2018-02-01

    We provide a numerical study of the macroscopic model of Barré et al. (Multiscale Model Simul, 2017, to appear) derived from an agent-based model for a system of particles interacting through a dynamical network of links. Assuming that the network remodeling process is very fast, the macroscopic model takes the form of a single aggregation-diffusion equation for the density of particles. The theoretical study of the macroscopic model gives precise criteria for the phase transitions of the steady states, and in the one-dimensional case, we show numerically that the stationary solutions of the microscopic model undergo the same phase transitions and bifurcation types as the macroscopic model. In the two-dimensional case, we show that the numerical simulations of the macroscopic model are in excellent agreement with the predicted theoretical values. This study provides a partial validation of the formal derivation of the macroscopic model from a microscopic formulation and shows that the former is a consistent approximation of an underlying particle dynamics, making it a powerful tool for the modeling of dynamical networks at a large scale.

  4. Particle Interactions Mediated by Dynamical Networks: Assessment of Macroscopic Descriptions.

    PubMed

    Barré, J; Carrillo, J A; Degond, P; Peurichard, D; Zatorska, E

    2018-01-01

    We provide a numerical study of the macroscopic model of Barré et al. (Multiscale Model Simul, 2017, to appear) derived from an agent-based model for a system of particles interacting through a dynamical network of links. Assuming that the network remodeling process is very fast, the macroscopic model takes the form of a single aggregation-diffusion equation for the density of particles. The theoretical study of the macroscopic model gives precise criteria for the phase transitions of the steady states, and in the one-dimensional case, we show numerically that the stationary solutions of the microscopic model undergo the same phase transitions and bifurcation types as the macroscopic model. In the two-dimensional case, we show that the numerical simulations of the macroscopic model are in excellent agreement with the predicted theoretical values. This study provides a partial validation of the formal derivation of the macroscopic model from a microscopic formulation and shows that the former is a consistent approximation of an underlying particle dynamics, making it a powerful tool for the modeling of dynamical networks at a large scale.

  5. Why the Heyd-Scuseria-Ernzerhof hybrid functional description of VO2 phases is not correct

    NASA Astrophysics Data System (ADS)

    Grau-Crespo, Ricardo; Wang, Hao; Schwingenschlögl, Udo

    2012-08-01

    In contrast with recent claims that the Heyd-Scuseria-Ernzerhof (HSE) screened hybrid functional can provide a good description of the electronic and magnetic structures of VO2 phases [Eyert, Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.107.016401 107, 016401 (2011)], we show here that the HSE lowest-energy solutions for both the low-temperature monoclinic (M1) phase and the high-temperature rutile (R) phase, which are obtained upon inclusion of spin polarization, are at odds with experimental observations. For the M1 phase the ground state is (but should not be) magnetic, while the ground state of the R phase, which is also spin polarized, is not (but should be) metallic. The energy difference between the low-temperature and high-temperature phases has strong discrepancies with the experimental latent heat.

  6. Non-stoquastic Hamiltonians in quantum annealing via geometric phases

    NASA Astrophysics Data System (ADS)

    Vinci, Walter; Lidar, Daniel A.

    2017-09-01

    We argue that a complete description of quantum annealing implemented with continuous variables must take into account the non-adiabatic Aharonov-Anandan geometric phase that arises when the system Hamiltonian changes during the anneal. We show that this geometric effect leads to the appearance of non-stoquasticity in the effective quantum Ising Hamiltonians that are typically used to describe quantum annealing with flux qubits. We explicitly demonstrate the effect of this geometric non-stoquasticity when quantum annealing is performed with a system of one and two coupled flux qubits. The realization of non-stoquastic Hamiltonians has important implications from a computational complexity perspective, since it is believed that in many cases quantum annealing with stoquastic Hamiltonians can be efficiently simulated via classical algorithms such as Quantum Monte Carlo. It is well known that the direct implementation of non-stoquastic Hamiltonians with flux qubits is particularly challenging. Our results suggest an alternative path for the implementation of non-stoquasticity via geometric phases that can be exploited for computational purposes.

  7. Implementation of science process skills using ICT-based approach to facilitate student life skills

    NASA Astrophysics Data System (ADS)

    Rahayu, Y. S.; Yuliani; Wijaya, B. R.

    2018-01-01

    The purpose of this study is to describe the results of the implementation of a teaching-learning package in Plant Physiology courses to improve the student’s life skills using the science process skills-based approach ICT. This research used 15 students of Biology Education of Undergraduate International Class who are in the Plant Physiology course. This study consists of two phases items, namely the development phase and implementation phase by using a one-shot case study design. Research parameters were the feasibility of lesson plans, student achievement, Including academic skills, thinking skills, and social skills. Data were descriptively Analyzed According to the characteristics of the existing data. The result shows that the feasibility of a lesson plan is very satisfied and can be improvements in student’s life skills, especially with regards to student’s thinking skills and scientific thinking skills. The results indicate that the science process skills using ICT-based approach can be effective methods to improve student’s life skills.

  8. 7 CFR 3403.4 - Three-phase program.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AGRICULTURE SMALL BUSINESS INNOVATION RESEARCH GRANTS PROGRAM Program Description § 3403.4 Three-phase program. The Small Business Innovation Research Grants Program is carried out in three separate phases...

  9. 7 CFR 3403.4 - Three-phase program.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGRICULTURE SMALL BUSINESS INNOVATION RESEARCH GRANTS PROGRAM Program Description § 3403.4 Three-phase program. The Small Business Innovation Research Grants Program is carried out in three separate phases...

  10. 7 CFR 3403.4 - Three-phase program.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AGRICULTURE SMALL BUSINESS INNOVATION RESEARCH GRANTS PROGRAM Program Description § 3403.4 Three-phase program. The Small Business Innovation Research Grants Program is carried out in three separate phases...

  11. Generalized thermodynamics of phase equilibria in scalar active matter

    NASA Astrophysics Data System (ADS)

    Solon, Alexandre P.; Stenhammar, Joakim; Cates, Michael E.; Kafri, Yariv; Tailleur, Julien

    2018-02-01

    Motility-induced phase separation (MIPS) arises generically in fluids of self-propelled particles when interactions lead to a kinetic slowdown at high densities. Starting from a continuum description of scalar active matter akin to a generalized Cahn-Hilliard equation, we give a general prescription for the mean densities of coexisting phases in flux-free steady states that amounts, at a hydrodynamics scale, to extremizing an effective free energy. We illustrate our approach on two well-known models: self-propelled particles interacting either through a density-dependent propulsion speed or via direct pairwise forces. Our theory accounts quantitatively for their phase diagrams, providing a unified description of MIPS.

  12. Transport dynamics of molecular motors that switch between an active and inactive state

    NASA Astrophysics Data System (ADS)

    Pinkoviezky, I.; Gov, N. S.

    2013-08-01

    Molecular motors are involved in key transport processes in the cell. Many of these motors can switch from an active to a nonactive state, either spontaneously or depending on their interaction with other molecules. When active, the motors move processively along the filaments, while when inactive they are stationary. We treat here the simple case of spontaneously switching motors, between the active and inactive states, along an open linear track. We use our recent analogy with vehicular traffic, where we go beyond the mean-field description. We map the phase diagram of this system, and find that it clearly breaks the symmetry between the different phases, as compared to the standard total asymmetric exclusion process. We make several predictions that may be testable using molecular motors in vitro and in living cells.

  13. van der Waals criticality in AdS black holes: A phenomenological study

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Krishnakanta; Majhi, Bibhas Ranjan; Samanta, Saurav

    2017-10-01

    Anti-de Sitter black holes exhibit van der Waals-type phase transition. In the extended phase-space formalism, the critical exponents for any spacetime metric are identical to the standard ones. Motivated by this fact, we give a general expression for the Helmholtz free energy near the critical point, which correctly reproduces these exponents. The idea is similar to the Landau model, which gives a phenomenological description of the usual second-order phase transition. Here, two main inputs are taken into account for the analysis: (a) black holes should have van der Waals-like isotherms, and (b) free energy can be expressed solely as a function of thermodynamic volume and horizon temperature. Resulting analysis shows that the form of Helmholtz free energy correctly encapsulates the features of the Landau function. We also discuss the isolated critical point accompanied by nonstandard values of critical exponents. The whole formalism is then extended to two other criticalities, namely, Y -X and T -S (based on the standard; i.e., nonextended phase space), where X and Y are generalized force and displacement, whereas T and S are the horizon temperature and entropy. We observe that in the former case Gibbs free energy plays the role of Landau function, whereas in the later case, that role is played by the internal energy (here, it is the black hole mass). Our analysis shows that, although the existence of a van der Waals phase transition depends on the explicit form of the black hole metric, the values of the critical exponents are universal in nature.

  14. Preface: Special Topic on Nuclear Quantum Effects

    NASA Astrophysics Data System (ADS)

    Tuckerman, Mark; Ceperley, David

    2018-03-01

    Although the observable universe strictly obeys the laws of quantum mechanics, in many instances, a classical description that either ignores quantum effects entirely or accounts for them at a very crude level is sufficient to describe a wide variety of phenomena. However, when this approximation breaks down, as is often the case for processes involving light nuclei, a full quantum treatment becomes indispensable. This Special Topic in The Journal of Chemical Physics showcases recent advances in our understanding of nuclear quantum effects in condensed phases as well as novel algorithmic developments and applications that have enhanced the capability to study these effects.

  15. Fluid dynamic and thermodynamic analysis of a model pertaining to cryogenic fluid management in low gravity environments for a system with dynamically induced settling

    NASA Technical Reports Server (NTRS)

    Rios, J.

    1982-01-01

    The settling behavior of the liquid and gaseous phases of a fluid in a propellant and in a zero-g environment, when such settling is induced through the use of a dynamic device, in this particular case, a helical screw was studied. Particular emphasis was given to: (1) the description of a fluid mechanics model which seems applicable to the system under consideration, (2) a First Law of Thermodynamics analysis of the system, and (3) a discussion of applicable scaling rules.

  16. All Internal Segmental Bone Transport and Optional Lengthening With a Newly Developed Universal Cylinder-Kombi-Tube Module for Motorized Nails-Description of a Surgical Technique.

    PubMed

    Krettek, Christian; El Naga, Ashraf

    2017-10-01

    Segmental transport is an effective method of treatment for segmental defects, but the need for external fixation during the transport phase is a disadvantage. To avoid external fixation, we have developed a Cylinder-Kombi-Tube Segmental Transport (CKTST) module for combination with a commercially available motorized lengthening nail. This CKTST module allows for an all-internal segmental bone transport and also allows for optional lengthening if needed. The concept and surgical technique of CKTST are described and illustrated with a clinical case.

  17. Preface: Special Topic on Nuclear Quantum Effects.

    PubMed

    Tuckerman, Mark; Ceperley, David

    2018-03-14

    Although the observable universe strictly obeys the laws of quantum mechanics, in many instances, a classical description that either ignores quantum effects entirely or accounts for them at a very crude level is sufficient to describe a wide variety of phenomena. However, when this approximation breaks down, as is often the case for processes involving light nuclei, a full quantum treatment becomes indispensable. This Special Topic in The Journal of Chemical Physics showcases recent advances in our understanding of nuclear quantum effects in condensed phases as well as novel algorithmic developments and applications that have enhanced the capability to study these effects.

  18. Periodic neutropenia and monocytopenia

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

    Adams, W.H.; Liu, Y.K.

    A patient with periodic neutropenia exhibited simultaneous monocytopenia, and epinephrine infusion revealed no monocytes in the marginating pool during neutropenia. Lymphocytes, eosinophils, and platelets also fluctuated periodically, but serial bone marrow studies and epinephrine infusion data indicate these fluctuations could have represented epiphenomena rather than a more global form of periodic hematopoiesis. Bone marrow descriptions of most cases of periodic neutropenia have indicated a ''maturation arrest'' at the promyelocyte or myelocyte stage prior to development of neutropenia; peripheral blood monocytes are usually normal or fluctuate out of phase with neutrophils. In the present case, ''maturation arrest'' occurred at the myeloblastmore » stage, and neutrophils and monocytes cycled together. Morphologically normal eosinophilopoiesis with a mean eosinophil to erythroid ratio in the marrow of 0.27 +/- 0.10 (SD) persisted despite a sustained disappearance of promyelocytes.« less

  19. Microscopic description of pair transfer between two superfluid Fermi systems: Combining phase-space averaging and combinatorial techniques

    NASA Astrophysics Data System (ADS)

    Regnier, David; Lacroix, Denis; Scamps, Guillaume; Hashimoto, Yukio

    2018-03-01

    In a mean-field description of superfluidity, particle number and gauge angle are treated as quasiclassical conjugated variables. This level of description was recently used to describe nuclear reactions around the Coulomb barrier. Important effects of the relative gauge angle between two identical superfluid nuclei (symmetric collisions) on transfer probabilities and fusion barrier have been uncovered. A theory making contact with experiments should at least average over different initial relative gauge-angles. In the present work, we propose a new approach to obtain the multiple pair transfer probabilities between superfluid systems. This method, called phase-space combinatorial (PSC) technique, relies both on phase-space averaging and combinatorial arguments to infer the full pair transfer probability distribution at the cost of multiple mean-field calculations only. After benchmarking this approach in a schematic model, we apply it to the collision 20O+20O at various energies below the Coulomb barrier. The predictions for one pair transfer are similar to results obtained with an approximated projection method, whereas significant differences are found for two pairs transfer. Finally, we investigated the applicability of the PSC method to the contact between nonidentical superfluid systems. A generalization of the method is proposed and applied to the schematic model showing that the pair transfer probabilities are reasonably reproduced. The applicability of the PSC method to asymmetric nuclear collisions is investigated for the 14O+20O collision and it turns out that unrealistically small single- and multiple pair transfer probabilities are obtained. This is explained by the fact that relative gauge angle play in this case a minor role in the particle transfer process compared to other mechanisms, such as equilibration of the charge/mass ratio. We conclude that the best ground for probing gauge-angle effects in nuclear reaction and/or for applying the proposed PSC approach on pair transfer is the collisions of identical open-shell spherical nuclei.

  20. Design of Training Systems, Phase II Report, Volume III; Model Program Descriptions and Operating Procedures. TAEG Report No. 12-2.

    ERIC Educational Resources Information Center

    Naval Training Equipment Center, Orlando, FL. Training Analysis and Evaluation Group.

    The Design of Training Systems (DOTS) project was initiated by the Department of Defense (DOD) to develop tools for the effective management of military training organizations. Volume 3 contains the model and data base program descriptions and operating procedures designed for phase 2 of the project. Flow charts and program listings for the…

  1. Generalized Finsler geometric continuum physics with applications in fracture and phase transformations

    NASA Astrophysics Data System (ADS)

    Clayton, J. D.

    2017-02-01

    A theory of deformation of continuous media based on concepts from Finsler differential geometry is presented. The general theory accounts for finite deformations, nonlinear elasticity, and changes in internal state of the material, the latter represented by elements of a state vector of generalized Finsler space whose entries consist of one or more order parameter(s). Two descriptive representations of the deformation gradient are considered. The first invokes an additive decomposition and is applied to problems involving localized inelastic deformation mechanisms such as fracture. The second invokes a multiplicative decomposition and is applied to problems involving distributed deformation mechanisms such as phase transformations or twinning. Appropriate free energy functions are posited for each case, and Euler-Lagrange equations of equilibrium are derived. Solutions are obtained for specific problems of tensile fracture of an elastic cylinder and for amorphization of a crystal under spherical and uniaxial compression. The Finsler-based approach is demonstrated to be more general and potentially more physically descriptive than existing hyperelasticity models couched in Riemannian geometry or Euclidean space, without incorporation of supplementary ad hoc equations or spurious fitting parameters. Predictions for single crystals of boron carbide ceramic agree qualitatively, and in many instances quantitatively, with results from physical experiments and atomic simulations involving structural collapse and failure of the crystal along its c-axis.

  2. Descriptive studies: what they can and cannot do.

    PubMed

    Grimes, David A; Schulz, Kenneth F

    2002-01-12

    Descriptive studies often represent the first scientific toe in the water in new areas of inquiry. A fundamental element of descriptive reporting is a clear, specific, and measurable definition of the disease or condition in question. Like newspapers, good descriptive reporting answers the five basic W questions: who, what, why, when, where. and a sixth: so what? Case reports, case-series reports, cross-sectional studies, and surveillance studies deal with individuals, whereas ecological correlational studies examine populations. The case report is the least-publishable unit in medical literature. Case-series reports aggregate individual cases in one publication. Clustering of unusual cases in a short period often heralds a new epidemic, as happened with AIDS. Cross-sectional (prevalence) studies describe the health of populations. Surveillance can be thought of as watchfulness over a community; feedback to those who need to know is an integral component of surveillance. Ecological correlational studies look for associations between exposures and outcomes in populations-eg, per capita cigarette sales and rates of coronary artery disease-rather than in individuals. Three important uses of descriptive studies include trend analysis, health-care planning, and hypothesis generation. A frequent error in reports of descriptive studies is overstepping the data: studies without a comparison group allow no inferences to be drawn about associations, causal or otherwise. Hypotheses about causation from descriptive studies are often tested in rigorous analytical studies.

  3. From phase space to integrable representations and level-rank duality

    NASA Astrophysics Data System (ADS)

    Chattopadhyay, Arghya; Dutta, Parikshit; Dutta, Suvankar

    2018-05-01

    We explicitly find representations for different large N phases of Chern-Simons matter theory on S 2 × S 1. These representations are characterised by Young diagrams. We show that no-gap and lower-gap phase of Chern-Simons-matter theory correspond to integrable representations of SU( N) k affine Lie algebra, where as upper-cap phase corresponds to integrable representations of SU( k - N) k affine Lie algebra. We use phase space description of [1] to obtain these representations and argue how putting a cap on eigenvalue distribution forces corresponding representations to be integrable. We also prove that the Young diagrams corresponding to lower-gap and upper-cap representations are related to each other by transposition under level-rank duality. Finally we draw phase space droplets for these phases and show how information about eigenvalue and Young diagram descriptions can be captured in topologies of these droplets in a unified way.

  4. Multi-phase-field modeling of anisotropic crack propagation for polycrystalline materials

    NASA Astrophysics Data System (ADS)

    Nguyen, Thanh-Tung; Réthoré, Julien; Yvonnet, Julien; Baietto, Marie-Christine

    2017-08-01

    A new multi-phase-field method is developed for modeling the fracture of polycrystals at the microstructural level. Inter and transgranular cracking, as well as anisotropic effects of both elasticity and preferential cleavage directions within each randomly oriented crystal are taken into account. For this purpose, the proposed phase field formulation includes: (a) a smeared description of grain boundaries as cohesive zones avoiding defining an additional phase for grains; (b) an anisotropic phase field model; (c) a multi-phase field formulation where each preferential cleavage direction is associated with a damage (phase field) variable. The obtained framework allows modeling interactions and competition between grains and grain boundary cracks, as well as their effects on the effective response of the material. The proposed model is illustrated through several numerical examples involving a full description of complex crack initiation and propagation within 2D and 3D models of polycrystals.

  5. 30 CFR 250.413 - What must my description of well drilling design criteria address?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... design criteria address? 250.413 Section 250.413 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... must my description of well drilling design criteria address? Your description of well drilling design... drilling and the completion phases, including the anticipated surface pressure used for designing the...

  6. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR CODING: DESCRIPTIVE QUESTIONNAIRE (UA-D-6.0)

    EPA Science Inventory

    This purpose of this SOP is to define the coding strategy for the Descriptive Questionnaire. This questionnaire was developed for use in the Arizona NHEXAS project and the "Border" study. Keywords: data; coding; descriptive questionnaire.

    The National Human Exposure Assessment...

  7. The Molybdenum titanium Phase Diagram Evaluated from Ab initio Calculations

    DTIC Science & Technology

    2016-10-07

    thermodynamic properties of this binary system are not well known and two conflicting descriptions of the β-phase stability have been presented in the...computational thermodynamics CALPHAD approach [13] and the Thermo-Calc software [14]. These studies led to two conflicting descriptions of the stability of...energy calculations, with an energy cutoff separating core and valence states of -6 Ry. 2.2. Thermodynamic modeling The formation enthalpy of a

  8. Performance/Design Requirements and Detailed Technical Description for a Computer-Directed Training Subsystem for Integration into the Air Force Phase II Base Level System.

    ERIC Educational Resources Information Center

    Butler, A. K.; And Others

    The performance/design requirements and a detailed technical description for a Computer-Directed Training Subsystem to be integrated into the Air Force Phase II Base Level System are described. The subsystem may be used for computer-assisted lesson construction and has presentation capability for on-the-job training for data automation, staff, and…

  9. Application of computational thermodynamics in the study of magnsium alloys and bulk metallic glasses

    NASA Astrophysics Data System (ADS)

    Cao, Hongbo

    In this thesis, the application of the computational thermodynamics has been explored on two subjects, the study of magnesium alloys (Chapter 1-5) and bulk metallic glasses (BMGs) (Chapter 6-9). For the former case, a strategy of experiments coupled with the CALPHAD approach was employed to establish a thermodynamic description of the quaternary system Mg-Al-Ca-Sr focusing on the Mg-rich phase equilibria. Multicomponent Mg-rich alloys based on the MgAl-Ca-Sr system are one of the most promising candidates for the high temperature applications in the transportation industry. The Mg-Al-Ca-Sr quaternary consists of four ternaries and six binaries. Thermodynamic descriptions of all constituent binaries are available in the literature. Thermodynamic descriptions of the two key ternaries, Mg-Al-Sr and Mg-Al-Ca, were obtained by an efficient and reliable methodology, combining computational thermodynamics with key experiments. The obtained thermodynamic descriptions were validated by performing extensive comparisons between the calculations and experimental information. Thermodynamic descriptions of the other two ternaries, MgCa-Sr and Al-Ca-Sr, were obtained by extrapolation. For the later case, a computational thermodynamic strategy was formulated to obtain a minor but optimum amount of additional element into a base alloy to improve its glass forming ability (GFA). This was done through thermodynamically calculating the maximum liquidus depressions caused by various alloying addition (or replacement) schemes. The success of this approach has been examined in two multicomponent systems, Zr-based Zr-Cu-Ni-Al-Ti and Cu-rich Cu-Zr-Ti-Y. For both cases, experimental results showed conclusively that the GFA increases more than 100% from the base alloy to the one with minor but optimal elemental addition. Furthermore, a thermodynamic computational approach was employed to identify the compositions of Zr-Ti-Ni-Cu-Al alloys exhibiting low-lying liquidus surfaces, which tend to favor the BMG formation. Guided by these calculations, several series of new Zr-based alloys with excellent GFA were synthesized. The approach using the thermodynamically calculated liquidus temperatures was proved to be robust in locating BMGs and can be considered as a universal method to predict novel BMGs not only of scientific interest but also potential technological applications.

  10. Descriptive Linear modeling of steady-state visual evoked response

    NASA Technical Reports Server (NTRS)

    Levison, W. H.; Junker, A. M.; Kenner, K.

    1986-01-01

    A study is being conducted to explore use of the steady state visual-evoke electrocortical response as an indicator of cognitive task loading. Application of linear descriptive modeling to steady state Visual Evoked Response (VER) data is summarized. Two aspects of linear modeling are reviewed: (1) unwrapping the phase-shift portion of the frequency response, and (2) parsimonious characterization of task-loading effects in terms of changes in model parameters. Model-based phase unwrapping appears to be most reliable in applications, such as manual control, where theoretical models are available. Linear descriptive modeling of the VER has not yet been shown to provide consistent and readily interpretable results.

  11. Objective coding of content and techniques in workplace-based supervision of an EBT in public mental health.

    PubMed

    Dorsey, Shannon; Kerns, Suzanne E U; Lucid, Leah; Pullmann, Michael D; Harrison, Julie P; Berliner, Lucy; Thompson, Kelly; Deblinger, Esther

    2018-01-24

    Workplace-based clinical supervision as an implementation strategy to support evidence-based treatment (EBT) in public mental health has received limited research attention. A commonly provided infrastructure support, it may offer a relatively cost-neutral implementation strategy for organizations. However, research has not objectively examined workplace-based supervision of EBT and specifically how it might differ from EBT supervision provided in efficacy and effectiveness trials. Data come from a descriptive study of supervision in the context of a state-funded EBT implementation effort. Verbal interactions from audio recordings of 438 supervision sessions between 28 supervisors and 70 clinicians from 17 public mental health organizations (in 23 offices) were objectively coded for presence and intensity coverage of 29 supervision strategies (16 content and 13 technique items), duration, and temporal focus. Random effects mixed models estimated proportion of variance in content and techniques attributable to the supervisor and clinician levels. Interrater reliability among coders was excellent. EBT cases averaged 12.4 min of supervision per session. Intensity of coverage for EBT content varied, with some discussed frequently at medium or high intensity (exposure) and others infrequently discussed or discussed only at low intensity (behavior management; assigning/reviewing client homework). Other than fidelity assessment, supervision techniques common in treatment trials (e.g., reviewing actual practice, behavioral rehearsal) were used rarely or primarily at low intensity. In general, EBT content clustered more at the clinician level; different techniques clustered at either the clinician or supervisor level. Workplace-based clinical supervision may be a feasible implementation strategy for supporting EBT implementation, yet it differs from supervision in treatment trials. Time allotted per case is limited, compressing time for EBT coverage. Techniques that involve observation of clinician skills are rarely used. Workplace-based supervision content appears to be tailored to individual clinicians and driven to some degree by the individual supervisor. Our findings point to areas for intervention to enhance the potential of workplace-based supervision for implementation effectiveness. NCT01800266 , Clinical Trials, Retrospectively Registered (for this descriptive study; registration prior to any intervention [part of phase II RCT, this manuscript is only phase I descriptive results]).

  12. A pilot study to determine whether combinations of objectively measured activity parameters can be used to differentiate between mixed states, mania, and bipolar depression.

    PubMed

    Scott, Jan; Vaaler, Arne E; Fasmer, Ole Bernt; Morken, Gunnar; Krane-Gartiser, Karoline

    2017-12-01

    Until recently, actigraphy studies in bipolar disorders focused on sleep rather than daytime activity in mania or depression, and have failed to analyse mixed episodes separately. Furthermore, even those studies that assessed activity parameters reported only mean levels rather than complexity or predictability of activity. We identified cases presenting in one of three acute phases of bipolar disorder and examined whether the application of non-linear dynamic models to the description of objectively measured activity can be used to predict case classification. The sample comprised 34 adults who were hospitalized with an acute episode of mania (n = 16), bipolar depression (n = 12), or a mixed state (n = 6), who agreed to wear an actiwatch for a continuous period of 24 h. Mean level, variability, regularity, entropy, and predictability of activity were recorded for a defined 64-min active morning and active evening period. Discriminant function analysis was used to determine the combination of variables that best classified cases based on phase of illness. The model identified two discriminant functions: the first was statistically significant and correlated with intra-individual fluctuation in activity and regularity of activity (sample entropy) in the active morning period; the second correlated with several measures of activity from the evening period (e.g. Fourier analysis, autocorrelation, sample entropy). A classification table generated from both functions correctly classified 79% of all cases based on phase of illness (χ 2  = 36.21; df 4; p = 0.001). However, 42% of bipolar depression cases were misclassified as being in manic phase. The findings should be treated with caution as this was a small-scale pilot study and we did not control for prescribed treatments, medication adherence, etc. However, the insights gained should encourage more widespread adoption of statistical approaches to the classification of cases alongside the application of more sophisticated modelling of activity patterns. The difficulty of accurately classifying cases of bipolar depression requires further research, as it is unclear whether the lower prediction rate reflects weaknesses in a model based only on actigraphy data, or if it reflects clinical reality i.e. the possibility that there may be more than one subtype of bipolar depression.

  13. IDC Reengineering Phase 2 Project Scope.

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

    Harris, James M.

    This report provides a brief description of the scope of the IDC Reengineering Phase 2 project. It describes the goals and objectives of reengineering, the system definition, and the technical scope of the system. REVISIONS Version Date Author/Team Revision Description Authorized by 1.0 9/25/2014 SNL IDC Reengineering Team Unlimited Release for I2 M. Harris 1.1 28/01/2015 IDC Reengineering Team Align with previous IDC scope document E. Tomuta.

  14. Effect of the substrate on the insulator-metal transition of vanadium dioxide films

    NASA Astrophysics Data System (ADS)

    Kovács, György J.; Bürger, Danilo; Skorupa, Ilona; Reuther, Helfried; Heller, René; Schmidt, Heidemarie

    2011-03-01

    Single-phase vanadium dioxide films grown on (0001) sapphire and (001) silicon substrates show a very different insulator-metal electronic transition. A detailed description of the growth mechanisms and the substrate-film interaction is given, and the characteristics of the electronic transition are described by the morphology and grain boundary structure. (Tri-)epitaxy-stabilized columnar growth of VO2 takes place on the sapphire substrate, whereas on silicon the expected Zone II growth is identified. We have found that in the case of the Si substrate the reasons for the broader hysteresis and the lower switching amplitude are the formation of an amorphous insulating VOx (x > 2.6) phase coexisting with VO2 and the high vanadium vacancy concentration of the VO2. These phenomena are the result of the excess oxygen during the growth and the interaction between the silicon substrate and the growing film.

  15. A first proposal for a general description model of forensic traces

    NASA Astrophysics Data System (ADS)

    Lindauer, Ina; Schäler, Martin; Vielhauer, Claus; Saake, Gunter; Hildebrandt, Mario

    2012-06-01

    In recent years, the amount of digitally captured traces at crime scenes increased rapidly. There are various kinds of such traces, like pick marks on locks, latent fingerprints on various surfaces as well as different micro traces. Those traces are different from each other not only in kind but also in which information they provide. Every kind of trace has its own properties (e.g., minutiae for fingerprints, or raking traces for locks) but there are also large amounts of metadata which all traces have in common like location, time and other additional information in relation to crime scenes. For selected types of crime scene traces, type-specific databases already exist, such as the ViCLAS for sexual offences, the IBIS for ballistic forensics or the AFIS for fingerprints. These existing forensic databases strongly differ in the trace description models. For forensic experts it would be beneficial to work with only one database capable of handling all possible forensic traces acquired at a crime scene. This is especially the case when different kinds of traces are interrelated (e.g., fingerprints and ballistic marks on a bullet casing). Unfortunately, current research on interrelated traces as well as general forensic data models and structures is not mature enough to build such an encompassing forensic database. Nevertheless, recent advances in the field of contact-less scanning make it possible to acquire different kinds of traces with the same device. Therefore the data of these traces is structured similarly what simplifies the design of a general forensic data model for different kinds of traces. In this paper we introduce a first common description model for different forensic trace types. Furthermore, we apply for selected trace types from the well established database schema development process the phases of transferring expert knowledge in the corresponding forensic fields into an extendible, database-driven, generalised forensic description model. The trace types considered here are fingerprint traces, traces at locks, micro traces and ballistic traces. Based on these basic trace types, also combined traces (multiple or overlapped fingerprints, fingerprints on bullet casings, etc) and partial traces are considered.

  16. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR CLEANING: DESCRIPTIVE QUESTIONNAIRES (UA-D-17.0)

    EPA Science Inventory

    The purpose of this SOP is to define the steps involved in cleaning the electronic data generated from data entry of the Descriptive Questionnaire. It applies to electronic data corresponding to the Descriptive Questionnaire that was scanned and verified by the Data Staff during...

  17. PWR PRELIMINARY DESIGN FOR PL-3

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

    Humphries, G. E.

    1962-02-28

    The pressurized water reactor preliminary design, the preferred design developed under Phase I of the PL-3 contract, is presented. Plant design criteria, summary of plant selection, plant description, reactor and primary system description, thermal and hydraulic analysis, nuclear analysis, control and instrumentatlon description, shielding description, auxiliary systems, power plant equipment, waste dispusal, buildings and tunnels, services, operation and maintenance, logistics, erection, cost information, and a training program outline are given. (auth)

  18. Confocal Raman microscope mapping as a tool to describe different mineral and organic phases at high spatial resolution within marine biogenic carbonates: case study on Nerita undata (Gastropoda, Neritopsina)

    NASA Astrophysics Data System (ADS)

    Nehrke, G.; Nouet, J.

    2011-12-01

    Marine biogenic carbonates formed by invertebrates (e.g. corals and mollusks) represent complex composites of one or more mineral phases and organic molecules. This complexity ranges from the macroscopic structures observed with the naked eye down to sub micrometric structures only revealed by micro analytical techniques. Understanding to what extent and how organisms can control the formation of these structures requires that the mineral and organic phases can be identified and their spatial distribution related. Here we demonstrate the capability of confocal Raman microscopy applied to cross sections of a shell of Nerita undata to describe the distribution of calcite and aragonite including their crystallographic orientation with high lateral resolution (~300 nm). Moreover, spatial distribution of functional groups of organic compounds can be simultaneously acquired, allowing to specifically relate them to the observed microstructures. The data presented in this case study highlights the possible new contributions of this method to the description of modalities of Nerita undata shell formation, and what could be expected of its application to other marine biogenic carbonates. Localization of areas of interest would also allow further investigations using more localized methods, such as TEM that would provide complementary information on the relation between organic molecules and crystal lattice.

  19. Confocal Raman microscopy as a tool to describe different mineral and organic phases at high spatial resolution within marine biogenic carbonates: case study on Nerita undata (Gastropoda, Neritopsina)

    NASA Astrophysics Data System (ADS)

    Nehrke, G.; Nouet, J.

    2011-06-01

    Marine biogenic carbonates formed by invertebrates (e.g. corals and mollusk shells) represent complex composites of one or more mineral phases and organic molecules. This complexity ranges from the macroscopic structures observed with the naked eye down to sub micrometric structures only revealed by micro analytical techniques. Understanding to what extent and how organisms can control the formation of these structures requires that the mineral and organic phases can be identified and their spatial distribution related. Here we demonstrate the capability of confocal Raman microscopy applied to cross sections of a shell of Nerita undata to describe the distribution of calcite and aragonite including their crystallographic orientation with high lateral resolution (∼300 nm). Moreover, spatial distribution of functional groups of organic compounds can be simultaneously acquired, allowing to specifically relate them to the observed microstructures. The data presented in this case study highlights the possible new contributions of this method to the description of modalities of Nerita undata shell formation, and what could be expected of its application to other marine biogenic carbonates. Localization of areas of interest would also allow further investigations using more localized methods, such as TEM that would provide complementary information on the relation between organic molecules and crystallographic lattice.

  20. Reliability of the one-crossing approximation in describing the Mott transition

    NASA Astrophysics Data System (ADS)

    Vildosola, V.; Pourovskii, L. V.; Manuel, L. O.; Roura-Bas, P.

    2015-12-01

    We assess the reliability of the one-crossing approximation (OCA) approach in a quantitative description of the Mott transition in the framework of the dynamical mean field theory (DMFT). The OCA approach has been applied in conjunction with DMFT to a number of heavy-fermion, actinide, transition metal compounds and nanoscale systems. However, several recent studies in the framework of impurity models pointed out serious deficiencies of OCA and raised questions regarding its reliability. Here we consider a single band Hubbard model on the Bethe lattice at finite temperatures and compare the results of OCA to those of a numerically exact quantum Monte Carlo (QMC) method. The temperature-local repulsion U phase diagram for the particle-hole symmetric case obtained by OCA is in good agreement with that of QMC, with the metal-insulator transition captured very well. We find, however, that the insulator to metal transition is shifted to higher values of U and, simultaneously, correlations in the metallic phase are significantly overestimated. This counter-intuitive behaviour is due to simultaneous underestimations of the Kondo scale in the metallic phase and the size of the insulating gap. We trace the underestimation of the insulating gap to that of the second moment of the high-frequency expansion of the impurity spectral density. Calculations of the system away from the particle-hole symmetric case are also presented and discussed.

  1. The effect of multiplicity of stellar encounters and the diffusion coefficients in a locally homogeneous three-dimensional stellar medium: Removing the classical divergence

    NASA Astrophysics Data System (ADS)

    Rastorguev, A. S.; Utkin, N. D.; Chumak, O. V.

    2017-08-01

    Agekyan's λ-factor that allows for the effect of multiplicity of stellar encounters with large impact parameters has been used for the first time to directly calculate the diffusion coefficients in the phase space of a stellar system. Simple estimates show that the cumulative effect, i.e., the total contribution of distant encounters to the change in the velocity of a test star, given the multiplicity of stellar encounters, is finite, and the logarithmic divergence inherent in the classical description of diffusion is removed, as was shown previously byKandrup using a different, more complex approach. In this case, the expressions for the diffusion coefficients, as in the classical description, contain the logarithm of the ratio of two independent quantities: the mean interparticle distance and the impact parameter of a close encounter. However, the physical meaning of this logarithmic factor changes radically: it reflects not the divergence but the presence of two characteristic length scales inherent in the stellar medium.

  2. Interfacial profiles in fluid/liquid systems: a description based on the storing of elastic energy.

    PubMed

    Castellanos-Suárez, Aly J; Toro-Mendoza, Jhoan; García-Sucre, Máximo

    2011-06-01

    An analytical expression for the interfacial energy is found by solving a Poisson equation and assuming a Boltzmann distribution of volume elements forming the fluid/liquid system. Interfacial phenomena are treated as a result of the response of a liquid when it makes contact with other fluid phase, in order to reach thermal and mechanical equilibrium. This model gives a quantitative description of the interface, obtaining values for its molar, force and energy density profiles. Also, our model allows the determination of the proportion of the fluids present in the interfacial zone, the values of interfacial tension and thickness. In the case of water+n-alkanes systems, the tensions are in agreement with the behavior shown by the experimental data. Finally, the values for interfacial thickness predicted from molar density profiles are lower than the range of influence of the elastic energy and elastic field. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. Equilibrium Contact Angle and Adsorption Layer Properties with Surfactants.

    PubMed

    Thiele, Uwe; Snoeijer, Jacco H; Trinschek, Sarah; John, Karin

    2018-06-19

    The three-phase contact line of a droplet on a smooth surface can be characterized by the Young equation. It relates the interfacial energies to the macroscopic contact angle θ e . On the mesoscale, wettability is modeled by a film-height-dependent wetting energy f( h). Macro- and mesoscale descriptions are consistent if γ cos θ e = γ + f( h a ), where γ and h a are the liquid-gas interface energy and the thickness of the equilibrium liquid adsorption layer, respectively. Here, we derive a similar consistency condition for the case of a liquid covered by an insoluble surfactant. At equilibrium, the surfactant is spatially inhomogeneously distributed, implying a nontrivial dependence of θ e on surfactant concentration. We derive macroscopic and mesoscopic descriptions of a contact line at equilibrium and show that they are consistent only if a particular dependence of the wetting energy on the surfactant concentration is imposed. This is illustrated by a simple example of dilute surfactants, for which we show excellent agreement between theory and time-dependent numerical simulations.

  4. Co-creating possibilities for patients in palliative care to reach vital goals--a multiple case study of home-care nursing encounters.

    PubMed

    Bergdahl, Elisabeth; Benzein, Eva; Ternestedt, Britt-Marie; Elmberger, Eva; Andershed, Birgitta

    2013-12-01

    The patient's home is a common setting for palliative care. This means that we need to understand current palliative care philosophy and how its goals can be realized in home-care nursing encounters (HCNEs) between the nurse, patient and patient's relatives. The existing research on this topic describes both a negative and a positive perspective. There has, however, been a reliance on interview and descriptive methods in this context. The aim of this study was to explore planned HCNEs in palliative care. The design was a multiple case study based on observations. The analysis includes a descriptive and an explanation building phase. The results show that planned palliative HCNEs can be described as a process of co-creating possibilities for the patient to reach vital goals through shared knowledge in a warm and caring atmosphere, based on good caring relations. However, in some HCNEs, co-creation did not occur: Wishes and needs were discouraged or made impossible and vital goals were not reached for the patients or their relatives. Further research is needed to understand why. The co-creative process presented in this article can be seen as a concretization of the palliative care ideal of working with a person-centered approach. © 2013 John Wiley & Sons Ltd.

  5. Active Brownian particles with velocity-alignment and active fluctuations

    NASA Astrophysics Data System (ADS)

    Großmann, R.; Schimansky-Geier, L.; Romanczuk, P.

    2012-07-01

    We consider a model of active Brownian particles (ABPs) with velocity alignment in two spatial dimensions with passive and active fluctuations. Here, active fluctuations refers to purely non-equilibrium stochastic forces correlated with the heading of an individual active particle. In the simplest case studied here, they are assumed to be independent stochastic forces parallel (speed noise) and perpendicular (angular noise) to the velocity of the particle. On the other hand, passive fluctuations are defined by a noise vector independent of the direction of motion of a particle, and may account, for example, for thermal fluctuations. We derive a macroscopic description of the ABP gas with velocity-alignment interaction. Here, we start from the individual-based description in terms of stochastic differential equations (Langevin equations) and derive equations of motion for the coarse-grained kinetic variables (density, velocity and temperature) via a moment expansion of the corresponding probability density function. We focus here on the different impact of active and passive fluctuations on onset of collective motion and show how active fluctuations in the active Brownian dynamics can change the phase-transition behaviour of the system. In particular, we show that active angular fluctuations lead to an earlier breakdown of collective motion and to the emergence of a new bistable regime in the mean-field case.

  6. Framework Programmable Platform for the Advanced Software Development Workstation (FPP/ASDW). Demonstration framework document. Volume 1: Concepts and activity descriptions

    NASA Technical Reports Server (NTRS)

    Mayer, Richard J.; Blinn, Thomas M.; Dewitte, Paul S.; Crump, John W.; Ackley, Keith A.

    1992-01-01

    The Framework Programmable Software Development Platform (FPP) is a project aimed at effectively combining tool and data integration mechanisms with a model of the software development process to provide an intelligent integrated software development environment. Guided by the model, this system development framework will take advantage of an integrated operating environment to automate effectively the management of the software development process so that costly mistakes during the development phase can be eliminated. The Advanced Software Development Workstation (ASDW) program is conducting research into development of advanced technologies for Computer Aided Software Engineering (CASE).

  7. Robust Feature Matching in Terrestrial Image Sequences

    NASA Astrophysics Data System (ADS)

    Abbas, A.; Ghuffar, S.

    2018-04-01

    From the last decade, the feature detection, description and matching techniques are most commonly exploited in various photogrammetric and computer vision applications, which includes: 3D reconstruction of scenes, image stitching for panoramic creation, image classification, or object recognition etc. However, in terrestrial imagery of urban scenes contains various issues, which include duplicate and identical structures (i.e. repeated windows and doors) that cause the problem in feature matching phase and ultimately lead to failure of results specially in case of camera pose and scene structure estimation. In this paper, we will address the issue related to ambiguous feature matching in urban environment due to repeating patterns.

  8. Finite-deformation phase-field chemomechanics for multiphase, multicomponent solids

    NASA Astrophysics Data System (ADS)

    Svendsen, Bob; Shanthraj, Pratheek; Raabe, Dierk

    2018-03-01

    The purpose of this work is the development of a framework for the formulation of geometrically non-linear inelastic chemomechanical models for a mixture of multiple chemical components diffusing among multiple transforming solid phases. The focus here is on general model formulation. No specific model or application is pursued in this work. To this end, basic balance and constitutive relations from non-equilibrium thermodynamics and continuum mixture theory are combined with a phase-field-based description of multicomponent solid phases and their interfaces. Solid phase modeling is based in particular on a chemomechanical free energy and stress relaxation via the evolution of phase-specific concentration fields, order-parameter fields (e.g., related to chemical ordering, structural ordering, or defects), and local internal variables. At the mixture level, differences or contrasts in phase composition and phase local deformation in phase interface regions are treated as mixture internal variables. In this context, various phase interface models are considered. In the equilibrium limit, phase contrasts in composition and local deformation in the phase interface region are determined via bulk energy minimization. On the chemical side, the equilibrium limit of the current model formulation reduces to a multicomponent, multiphase, generalization of existing two-phase binary alloy interface equilibrium conditions (e.g., KKS). On the mechanical side, the equilibrium limit of one interface model considered represents a multiphase generalization of Reuss-Sachs conditions from mechanical homogenization theory. Analogously, other interface models considered represent generalizations of interface equilibrium conditions consistent with laminate and sharp-interface theory. In the last part of the work, selected existing models are formulated within the current framework as special cases and discussed in detail.

  9. Classical and quantum fold catastrophe in the presence of axial symmetry

    NASA Astrophysics Data System (ADS)

    Dhont, G.; Zhilinskií, B. I.

    2008-11-01

    We introduce a family of Hamiltonians with two degrees of freedom, axial symmetry and complete integrability. The potential function depends on coordinates and one control parameter. A fold catastrophe typically occurs in such a family of potentials and its consequences on the global dynamics are investigated through the energy-momentum map which defines the singular fibration of the four-dimensional phase space. The two inequivalent local canonical forms of the catastrophe are presented: the first case corresponds to the appearance of a second sheet in the image of the energy-momentum map while the second case is associated with the breaking of an already existing second sheet. A special effort is placed on the description of the singularities. In particular, the existence of cuspidal tori is related to a second-order contact point between the energy level set and the reduced phase space. The quantum mechanical aspects of the changes induced by the fold catastrophe are investigated with the quantum eigenstates computed for an octic potential and are interpreted through the quantum-classical correspondence. We note that the singularity exposed in this paper is not an obstruction to a global definition of action-angle variables.

  10. Fall incidents unraveled: a series of 26 video-based real-life fall events in three frail older persons

    PubMed Central

    2013-01-01

    Background For prevention and detection of falls, it is essential to unravel the way in which older people fall. This study aims to provide a description of video-based real-life fall events and to examine real-life falls using the classification system by Noury and colleagues, which divides a fall into four phases (the prefall, critical, postfall and recovery phase). Methods Observational study of three older persons at high risk for falls, residing in assisted living or residential care facilities: a camera system was installed in each participant’s room covering all areas, using a centralized PC platform in combination with standard Internet Protocol (IP) cameras. After a fall, two independent researchers analyzed recorded images using the camera position with the clearest viewpoint. Results A total of 30 falls occurred of which 26 were recorded on camera over 17 months. Most falls happened in the morning or evening (62%), when no other persons were present (88%). Participants mainly fell backward (initial fall direction and landing configuration) on the pelvis or torso and none could get up unaided. In cases where a call alarm was used (54%), an average of 70 seconds (SD=64; range 15–224) was needed to call for help. Staff responded to the call after an average of eight minutes (SD=8.4; range 2–33). Mean time on the ground was 28 minutes (SD=25.4; range 2–59) without using a call alarm compared to 11 minutes (SD=9.2; range 3–38) when using a call alarm (p=0.445). The real life falls were comparable with the prefall and recovery phase of Noury’s classification system. The critical phase, however, showed a prolonged duration in all falls. We suggest distinguishing two separate phases: a prolonged loss of balance phase and the actual descending phase after failure to recover balance, resulting in the impact of the body on the ground. In contrast to the theoretical description, the postfall phase was not typically characterized by inactivity; this depended on the individual. Conclusions This study contributes to a better understanding of the fall process in private areas of assisted living and residential care settings in older persons at high risk for falls. PMID:24090211

  11. Determination of relative phase permeabilities in stochastic model of pore channel distribution by diameter

    NASA Astrophysics Data System (ADS)

    Zemenkova, M. Y.; Shabarov, A.; Shatalov, A.; Puldas, L.

    2018-05-01

    The problem of the pore space description and the calculation of relative phase permeabilities (RPP) for two-phase filtration is considered. A technique for constructing a pore-network structure for constant and variable channel diameters is proposed. A description of the design model of RPP based on the capillary pressure curves is presented taking into account the variability of diameters along the length of pore channels. By the example of the calculation analysis for the core samples of the Urnenskoye and Verkhnechonskoye deposits, the possibilities of calculating RPP are shown when using the stochastic distribution of pores by diameters and medium-flow diameters.

  12. Motion of vortices in inhomogeneous Bose-Einstein condensates

    NASA Astrophysics Data System (ADS)

    Groszek, Andrew J.; Paganin, David M.; Helmerson, Kristian; Simula, Tapio P.

    2018-02-01

    We derive a general and exact equation of motion for a quantized vortex in an inhomogeneous two-dimensional Bose-Einstein condensate. This equation expresses the velocity of a vortex as a sum of local ambient density and phase gradients in the vicinity of the vortex. We perform Gross-Pitaevskii simulations of single-vortex dynamics in both harmonic and hard-walled disk-shaped traps, and find excellent agreement in both cases with our analytical prediction. The simulations reveal that, in a harmonic trap, the main contribution to the vortex velocity is an induced ambient phase gradient, a finding that contradicts the commonly quoted result that the local density gradient is the only relevant effect in this scenario. We use our analytical vortex velocity formula to derive a point-vortex model that accounts for both density and phase contributions to the vortex velocity, suitable for use in inhomogeneous condensates. Although good agreement is obtained between Gross-Pitaevskii and point-vortex simulations for specific few-vortex configurations, the effects of nonuniform condensate density are in general highly nontrivial, and are thus difficult to efficiently and accurately model using a simplified point-vortex description.

  13. Crystalline phases involved in the hydration of calcium silicate-based cements: Semi-quantitative Rietveld X-ray diffraction analysis.

    PubMed

    Grazziotin-Soares, Renata; Nekoofar, Mohammad H; Davies, Thomas; Hübler, Roberto; Meraji, Naghmeh; Dummer, Paul M H

    2017-08-30

    Chemical comparisons of powder and hydrated forms of calcium silicate cements (CSCs) and calculation of alterations in tricalcium silicate (Ca 3 SiO 5 ) calcium hydroxide (Ca(OH) 2 ) are essential for understanding their hydration processes. This study aimed to evaluate and compare these changes in ProRoot MTA, Biodentine and CEM cement. Powder and hydrated forms of tooth coloured ProRoot MTA, Biodentine and CEM cement were subjected to X-ray diffraction (XRD) analysis with Rietveld refinement to semi-quantitatively identify and quantify the main phases involved in their hydration process. Data were reported descriptively. Reduction in Ca 3 SiO 5 and formation of Ca(OH) 2 were seen after the hydration of ProRoot MTA and Biodentine; however, in the case of CEM cement, no reduction of Ca 3 SiO 5 and no formation of Ca(OH) 2 were detected. The highest percentages of amorphous phases were seen in Biodentine samples. Ettringite was detected in the hydrated forms of ProRoot MTA and CEM cement but not in Biodentine. © 2017 Australian Society of Endodontology Inc.

  14. 78 FR 21353 - Combined Notice of Filings #1

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-10

    ... Company. Description: Mississippi Power Company submits 2011 MRA Rate Case Compliance Filing to be...: Mississippi Power Company. Description: Mississippi Power Company submits MRA 24 Rate Case Filing to be...

  15. World Perspective Case Descriptions on Educational Programs for Adults: Chile.

    ERIC Educational Resources Information Center

    Donoso, Patricio; Gajardo, Marcela

    This document contains two case studies of adult education programs in Chile. Both case studies begin with a "face sheet" on which is recorded basic information about the program and the description. The first case study, prepared by Patricio Donoso, reports on Centro El Canelo de Nos, an inservice center for educators who work with…

  16. Identifying cases of undiagnosed, clinically significant COPD in primary care: qualitative insight from patients in the target population

    PubMed Central

    Leidy, Nancy K; Kim, Katherine; Bacci, Elizabeth D; Yawn, Barbara P; Mannino, David M; Thomashow, Byron M; Barr, R Graham; Rennard, Stephen I; Houfek, Julia F; Han, Meilan K; Meldrum, Catherine A; Make, Barry J; Bowler, Russ P; Steenrod, Anna W; Murray, Lindsey T; Walsh, John W; Martinez, Fernando

    2015-01-01

    Background: Many cases of chronic obstructive pulmonary disease (COPD) are diagnosed only after significant loss of lung function or during exacerbations. Aims: This study is part of a multi-method approach to develop a new screening instrument for identifying undiagnosed, clinically significant COPD in primary care. Methods: Subjects with varied histories of COPD diagnosis, risk factors and history of exacerbations were recruited through five US clinics (four pulmonary, one primary care). Phase I: Eight focus groups and six telephone interviews were conducted to elicit descriptions of risk factors for COPD, recent or historical acute respiratory events, and symptoms to inform the development of candidate items for the new questionnaire. Phase II: A new cohort of subjects participated in cognitive interviews to assess and modify candidate items. Two peak expiratory flow (PEF) devices (electronic, manual) were assessed for use in screening. Results: Of 77 subjects, 50 participated in Phase I and 27 in Phase II. Six themes informed item development: exposure (smoking, second-hand smoke); health history (family history of lung problems, recurrent chest infections); recent history of respiratory events (clinic visits, hospitalisations); symptoms (respiratory, non-respiratory); impact (activity limitations); and attribution (age, obesity). PEF devices were rated easy to use; electronic values were significantly higher than manual (P<0.0001). Revisions were made to the draft items on the basis of cognitive interviews. Conclusions: Forty-eight candidate items are ready for quantitative testing to select the best, smallest set of questions that, together with PEF, can efficiently identify patients in need of diagnostic evaluation for clinically significant COPD. PMID:26028486

  17. Proper Orthogonal Decomposition on Experimental Multi-phase Flow in a Pipe

    NASA Astrophysics Data System (ADS)

    Viggiano, Bianca; Tutkun, Murat; Cal, Raúl Bayoán

    2016-11-01

    Multi-phase flow in a 10 cm diameter pipe is analyzed using proper orthogonal decomposition. The data were obtained using X-ray computed tomography in the Well Flow Loop at the Institute for Energy Technology in Kjeller, Norway. The system consists of two sources and two detectors; one camera records the vertical beams and one camera records the horizontal beams. The X-ray system allows measurement of phase holdup, cross-sectional phase distributions and gas-liquid interface characteristics within the pipe. The mathematical framework in the context of multi-phase flows is developed. Phase fractions of a two-phase (gas-liquid) flow are analyzed and a reduced order description of the flow is generated. Experimental data deepens the complexity of the analysis with limited known quantities for reconstruction. Comparison between the reconstructed fields and the full data set allows observation of the important features. The mathematical description obtained from the decomposition will deepen the understanding of multi-phase flow characteristics and is applicable to fluidized beds, hydroelectric power and nuclear processes to name a few.

  18. Universalities of thermodynamic signatures in topological phases

    PubMed Central

    Kempkes, S. N.; Quelle, A.; Smith, C. Morais

    2016-01-01

    Topological insulators (superconductors) are materials that host symmetry-protected metallic edge states in an insulating (superconducting) bulk. Although they are well understood, a thermodynamic description of these materials remained elusive, firstly because the edges yield a non-extensive contribution to the thermodynamic potential, and secondly because topological field theories involve non-local order parameters, and cannot be captured by the Ginzburg-Landau formalism. Recently, this challenge has been overcome: by using Hill thermodynamics to describe the Bernevig-Hughes-Zhang model in two dimensions, it was shown that at the topological phase transition the thermodynamic potential does not scale extensively due to boundary effects. Here, we extend this approach to different topological models in various dimensions (the Kitaev chain and Su-Schrieffer-Heeger model in one dimension, the Kane-Mele model in two dimensions and the Bernevig-Hughes-Zhang model in three dimensions) at zero temperature. Surprisingly, all models exhibit the same universal behavior in the order of the topological-phase transition, depending on the dimension. Moreover, we derive the topological phase diagram at finite temperature using this thermodynamic description, and show that it displays a good agreement with the one calculated from the Uhlmann phase. Our work reveals unexpected universalities and opens the path to a thermodynamic description of systems with a non-local order parameter. PMID:27929041

  19. Universalities of thermodynamic signatures in topological phases.

    PubMed

    Kempkes, S N; Quelle, A; Smith, C Morais

    2016-12-08

    Topological insulators (superconductors) are materials that host symmetry-protected metallic edge states in an insulating (superconducting) bulk. Although they are well understood, a thermodynamic description of these materials remained elusive, firstly because the edges yield a non-extensive contribution to the thermodynamic potential, and secondly because topological field theories involve non-local order parameters, and cannot be captured by the Ginzburg-Landau formalism. Recently, this challenge has been overcome: by using Hill thermodynamics to describe the Bernevig-Hughes-Zhang model in two dimensions, it was shown that at the topological phase transition the thermodynamic potential does not scale extensively due to boundary effects. Here, we extend this approach to different topological models in various dimensions (the Kitaev chain and Su-Schrieffer-Heeger model in one dimension, the Kane-Mele model in two dimensions and the Bernevig-Hughes-Zhang model in three dimensions) at zero temperature. Surprisingly, all models exhibit the same universal behavior in the order of the topological-phase transition, depending on the dimension. Moreover, we derive the topological phase diagram at finite temperature using this thermodynamic description, and show that it displays a good agreement with the one calculated from the Uhlmann phase. Our work reveals unexpected universalities and opens the path to a thermodynamic description of systems with a non-local order parameter.

  20. Long-wavelength instabilities in a system of interacting active particles

    NASA Astrophysics Data System (ADS)

    Fazli, Zahra; Najafi, Ali

    2018-02-01

    Based on a microscopic model, we develop a continuum description for a suspension of microscopic self-propelled particles. With this continuum description we study the role of long-range interactions in destabilizing macroscopic ordered phases that are developed by short-range interactions. Long-wavelength fluctuations can destabilize both isotropic and symmetry-broken polar phases in a suspension of dipolar particles. The instabilities in a suspension of pullers (pushers) arise from splay (bend) fluctuations. Such instabilities are not seen in a suspension of quadrupolar particles.

  1. Control of gel swelling and phase separation of weakly charged thermoreversible gels by salt addition

    PubMed Central

    Solis, Francisco J.; Vernon, Brent

    2009-01-01

    Doping of thermoreversible polymer gels with charged monomers provides a way to control phase separation and gelation conditions by coupling the properties of the gel with a tunable ionic environment. We analyze the dependence of the gelation and phase separation conditions on the amount of salt present using a mean field model of weakly charged associative polymers. The ions and co-ions present are explicitly considered at the mean field level, and we determine their concentrations in the different equilibrium phases when the system undergoes phase separation. For weak polymer charge, the entropic contributions of the ions to the free energy of the system play a central role in the determination of the location of phase equilibrium. In the simplest case, when the associative interaction responsible for gel formation is independent of the electrostatic interaction, the addition of salt changes the polymer equilibrium concentrations and indirectly changes the measurable swelling of the gel. We construct phase diagrams of these systems showing the location of the coexistence region, the gel-sol boundary and the location of the tie-lines. We determine the swelling of the gel within the co-existence region. Our main result is that the description of the effect of the salt on the properties of the weakly charged gel can be described through an extra contribution to the effective immiscibility parameter χ proportional to the square of the doping degree f2 and to the inverse square of the added salt concentration s−2. PMID:19759854

  2. The diffusion of the distance Entomology Master's Degree Program at the University of Nebraska Lincoln: A descriptive case study

    NASA Astrophysics Data System (ADS)

    Hubbell, Jody M.

    This study explored three selected phases of Rogers' (1995) Diffusion of Innovations Theory to examine the diffusion process of the distance Entomology Master's Degree program at the University of Nebraska, Lincoln. A qualitative descriptive case study approach incorporated semi-structured interviews with individuals involved in one or more of the three stages: Development, Implementation, and Institutionalization. Documents and archival evidence were used to triangulate findings. This research analyzed descriptions of the program as it moved from the Development, to the Implementation, and finally, the Institutionalization stages of diffusion. Each respective stage was examined through open and axial coding. Process coding identified themes common to two or more diffusion stages, and explored the evolution of themes from one diffusion stage to the next. At a time of significant budget constraints, many departments were faced with the possibility of merger or dissolution. The Entomology Master's Degree Program evolved from being an entrepreneurial means to prevent departmental dissolution to eventually being viewed as a model for the development of similar programs across this university and other institutions of higher education. During this evolution, the program was reinvented to meet the broader needs of industry and a global student market. One finding not consistent with Rogers' model was that smaller, rather than larger, departmental size contributed to the success of the program. Within this small department, faculty members were able to share their experiences and knowledge with each other on a regular basis, which promoted greater acceptance of the distance program. How quality and rigor may be defined and measured was a key issue in each respective stage. In this specific case, quality and rigor was initially a comparison of on-campus and distance course content and then moved to program-based assessment and measures of student outcomes such as job placement rates.

  3. Geophysical aspects of underground fluid dynamics and mineral transformation process

    NASA Astrophysics Data System (ADS)

    Khramchenkov, Maxim; Khramchenkov, Eduard

    2014-05-01

    The description of processes of mass exchange between fluid and poly-minerals material in porous media from various kinds of rocks (primarily, sedimentary rocks) have been examined. It was shown that in some important cases there is a storage equation of non-linear diffusion equation type. In addition, process of filtration in un-swelling soils, swelling porous rocks and coupled process of consolidation and chemical interaction between fluid and particles material were considered. In the latter case equations of physical-chemical mechanics of conservation of mass for fluid and particles material were used. As it is well known, the mechanics of porous media is theoretical basis of such branches of science as rock mechanics, soil physics and so on. But at the same moment some complex processes in the geosystems lacks full theoretical description. The example of such processes is metamorphosis of rocks and correspondent variations of stress-strain state. In such processes chemical transformation of solid and fluid components, heat release and absorption, phase transitions, rock destruction occurs. Extensive usage of computational resources in limits of traditional models of the mechanics of porous media cannot guarantee full correctness of obtained models and results. The process of rocks consolidation which happens due to filtration of underground fluids is described from the position of rock mechanics. As an additional impact, let us consider the porous media consolidating under the weight of overlying rock with coupled complex geological processes, as a continuous porous medium of variable mass. Problems of obtaining of correct storage equations for coupled processes of consolidation and mass exchange between underground fluid and skeleton material are often met in catagenesi processes description. The example of such processes is metamorphosis of rocks and correspondent variations of stress-strain state. In such processes chemical transformation of solid and fluid components, heat release and absorption, phase transitions, rock destruction occurs. Extensive usage of computational resources in limits of traditional models of the mechanics of porous media cannot guarantee full correctness of obtained models and results. The present work is dedicated to the retrieval of new ways to formulate and construct such models. It was shown that in some important cases there is a governing equation of non-linear diffusion equation type (well-known Fisher equation). In addition, some geophysical aspects of filtration process in usual non-swelling soils, swelling porous rocks and coupled process of consolidation and chemical interaction between fluid and skeleton material, including earth quakes, are considered.

  4. The two Faces of Equipartition

    NASA Astrophysics Data System (ADS)

    Sanchez-Sesma, F. J.; Perton, M.; Rodriguez-Castellanos, A.; Campillo, M.; Weaver, R. L.; Rodriguez, M.; Prieto, G.; Luzon, F.; McGarr, A.

    2008-12-01

    Equipartition is good. Beyond its philosophical implications, in many instances of statistical physics it implies that the available kinetic and potential elastic energy, in phase space, is distributed in the same fixed proportions among the possible "states". There are at least two distinct and complementary descriptions of such states in a diffuse elastic wave field u(r,t). One asserts that u may be represented as an incoherent isotropic superposition of incident plane waves of different polarizations. Each type of wave has an appropriate share of the available energy. This definition introduced by Weaver is similar to the room acoustics notion of a diffuse field, and it suffices to permit prediction of field correlations. The other description assumes that the degrees of freedom of the system, in this case, the kinetic energy densities, are all incoherently excited with equal expected amplitude. This definition, introduced by Maxwell, is also familiar from room acoustics using the normal modes of vibration within an arbitrarily large body. Usually, to establish if an elastic field is diffuse and equipartitioned only the first description has been applied, which requires the separation of dilatational and shear waves using carefully designed experiments. When the medium is bounded by an interface, waves of other modes, for example Rayleigh waves, complicate the measurement of these energies. As a consequence, it can be advantageous to use the second description. Moreover, each spatial component of the energy densities is linked, when an elastic field is diffuse and equipartitioned, to the component of the imaginary part of the Green function at the source. Accordingly, one can use the second description to retrieve the Green function and obtain more information about the medium. The equivalence between the two descriptions of equipartition are given for an infinite space and extended to the case of a half-space. These two descriptiosn are equivalent thanks to the relationship of average autocorrelations with the imaginary part of Green function at the source. Preliminary results are displayed in data sets from Chilpancingo, Mexico, and the Tautona Gold Mine, South Africa, that strongly suggest that equipartition, that guarantees the diffuse nature of seismic fields, has more than one face. Acknowledgements. Partial supports from DGAPA-UNAM, Project IN114706, Mexico; from Proyect MCyT CGL2005-05500-C02/BTE, Spain; from project DyETI of INSU-CNRS, France, and from the Instituto Mexicano del Petróleo are greatly appreciated.

  5. Experimental investigation of the phase equilibria and thermodynamic assessment in the U-Ga and U-Al-Ga systems

    NASA Astrophysics Data System (ADS)

    Moussa, Chantal; Berche, Alexandre; Barbosa, José; Pasturel, Mathieu; Stepnik, Bertrand; Tougait, Olivier

    2018-02-01

    The phase relations in the binary U-Ga and ternary U-Al-Ga systems were established as an isopleth section and two isothermal sections at 900 K and 1150 K for the whole concentration range, respectively. They were experimentally determined by means of powder and single crystal XRD, SEM-EDS analyses on both as-cast and heat-treated samples and DTA measurements. Both systems were thermodynamically assessed using the Calphad method based on the available data, i.e. phase relations and thermodynamic properties. The new description of the U-Ga phase diagram improves the composition-temperature description for most of invariant reactions. The U-Al-Ga system is characterized by large ternary extensions of the binary phases and the absence of ternary intermediate phase at both 900 K and 1150 K. These experimental results are nicely reproduced by the Calphad assessment, allowing to extract the thermodynamic parameters further used to calculate the liquidus projection and the invariant reactions along with their temperature.

  6. Interactomes to Biological Phase Space: a call to begin thinking at a new level in computational biology.

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

    Davidson, George S.; Brown, William Michael

    2007-09-01

    Techniques for high throughput determinations of interactomes, together with high resolution protein collocalizations maps within organelles and through membranes will soon create a vast resource. With these data, biological descriptions, akin to the high dimensional phase spaces familiar to physicists, will become possible. These descriptions will capture sufficient information to make possible realistic, system-level models of cells. The descriptions and the computational models they enable will require powerful computing techniques. This report is offered as a call to the computational biology community to begin thinking at this scale and as a challenge to develop the required algorithms and codes tomore » make use of the new data.3« less

  7. Driving for successful change processes in healthcare by putting staff at the wheel.

    PubMed

    Erlingsdottir, Gudbjörg; Ersson, Anders; Borell, Jonas; Rydenfält, Christofer

    2018-03-19

    Purpose The purpose of this paper is to describe five salient factors that emerge in two successful change processes in healthcare. Organizational changes in healthcare are often characterized by problems and solutions that have been formulated by higher levels of management. This top-down management approach has not been well received by the professional community. As a result, improvement processes are frequently abandoned, resulting in disrupted and dysfunctional organizations. This paper presents two successful change processes where managerial leadership was used to coach the change processes by distributing mandates and resources. After being managerially initiated, both processes were driven by local agency, decisions, planning and engagement. Design/methodology/approach The data in the paper derive from two qualitative case studies. Data were collected through in-depth interviews, observations and document studies. The cases are presented as process descriptions covering the different phases of the change processes. The focus in the studies is on the roles and interactions of the actors involved, the type of leadership and the distribution of agency. Findings Five factors emerged as paramount to the successful change processes in the two cases: local ownership of problems; a coached process where management initiates the change process and the problem recognition, and then lets the staff define the problems, formulate solutions and drive necessary changes; distributed leadership directed at enabling and supporting the staff's intentions and long-term self-leadership; mutually formulated norms and values that serve as a unifying force for the staff; and generous time allocation and planning, which allows the process to take time, and creates room for reevaluation. The authors also noted that in both cases, reorganization into multi-professional teams lent stability and endurance to the completed changes. Originality/value The research shows how management can initiate and support successful change processes that are staff driven and characterized by local agency, decisions, planning and engagement. Empirical descriptions of successful change processes are rare, which is why the description of such processes in this research increases the value of the paper.

  8. Phase transitions in Yang-Mills theories and their gravity duals

    NASA Astrophysics Data System (ADS)

    Marsano, Joseph Daniel

    This thesis is a study of the thermal phase structure of systems that admit dual gauge theory and string theory descriptions. In a pair of examples, we explore the connection between perturbative Yang-Mills and gravitational thermodynamics which arises from the fact that these descriptions probe different corners of a single phase diagram. The structure that emerges from a detailed study of these isolated regions generally suggests a natural conjecture how they may be connected to one another within the full phase diagram. This permits the identification of interesting phenomena in the gauge and gravity regimes under a continuous change in parameters. We begin by studying the AdS5/CFT 4 system which, when the supergravity description is valid, exhibits a first order Hawking-Page phase transition as a function of temperature from a thermal gas of gravitons to a large black hole. In the perturbative Yang-Mills regime, we find that the free theory exhibits a weakly first order deconfinement transition whose precise nature at small nonzero coupling depends on the result of a nontrivial perturbative computation. It is conjectured that this deconfinement transition is continuously connected in the full phase diagram to the Hawking-Page transition at strong coupling, with the confined phase identified with the graviton gas and the deconfined phase identified with the black hole. We then turn to the study of Gregory-Laflamme (GL) black hole/black string transitions in supergravity and their realization in a setup that admits a dual description via the maximally supersymmetric Yang-Mills theory on T2. The thermodynamics of Yang-Mills theories on low dimensional tori is studied in detail revealing an intricate structure of which the GL transition at strong coupling is a small piece. We are led to conjecture that GL physics is continuously connected to deconfinement in maximally supersymmetric 0 + 1-dimensional gauged matrix quantum mechanics. This identification will then permit us to probe GL transitions from the gauge theory point of view and comment on some puzzles regarding their precise nature.

  9. Space station integrated propulsion and fluid systems study. Space station program fluid management systems databook

    NASA Technical Reports Server (NTRS)

    Bicknell, B.; Wilson, S.; Dennis, M.; Lydon, M.

    1988-01-01

    Commonality and integration of propulsion and fluid systems associated with the Space Station elements are being evaluated. The Space Station elements consist of the core station, which includes habitation and laboratory modules, nodes, airlocks, and trusswork; and associated vehicles, platforms, experiments, and payloads. The program is being performed as two discrete tasks. Task 1 investigated the components of the Space Station architecture to determine the feasibility and practicality of commonality and integration among the various propulsion elements. This task was completed. Task 2 is examining integration and commonality among fluid systems which were identified by the Phase B Space Station contractors as being part of the initial operating capability (IOC) and growth Space Station architectures. Requirements and descriptions for reference fluid systems were compiled from Space Station documentation and other sources. The fluid systems being examined are: an experiment gas supply system, an oxygen/hydrogen supply system, an integrated water system, the integrated nitrogen system, and the integrated waste fluids system. Definitions and descriptions of alternate systems were developed, along with analyses and discussions of their benefits and detriments. This databook includes fluid systems descriptions, requirements, schematic diagrams, component lists, and discussions of the fluid systems. In addition, cost comparison are used in some cases to determine the optimum system for a specific task.

  10. A Case Study of Measuring Process Risk for Early Insights into Software Safety

    NASA Technical Reports Server (NTRS)

    Layman, Lucas; Basili, Victor; Zelkowitz, Marvin V.; Fisher, Karen L.

    2011-01-01

    In this case study, we examine software safety risk in three flight hardware systems in NASA's Constellation spaceflight program. We applied our Technical and Process Risk Measurement (TPRM) methodology to the Constellation hazard analysis process to quantify the technical and process risks involving software safety in the early design phase of these projects. We analyzed 154 hazard reports and collected metrics to measure the prevalence of software in hazards and the specificity of descriptions of software causes of hazardous conditions. We found that 49-70% of 154 hazardous conditions could be caused by software or software was involved in the prevention of the hazardous condition. We also found that 12-17% of the 2013 hazard causes involved software, and that 23-29% of all causes had a software control. The application of the TPRM methodology identified process risks in the application of the hazard analysis process itself that may lead to software safety risk.

  11. Injector Design Tool Improvements: User's manual for FDNS V.4.5

    NASA Technical Reports Server (NTRS)

    Chen, Yen-Sen; Shang, Huan-Min; Wei, Hong; Liu, Jiwen

    1998-01-01

    The major emphasis of the current effort is in the development and validation of an efficient parallel machine computational model, based on the FDNS code, to analyze the fluid dynamics of a wide variety of liquid jet configurations for general liquid rocket engine injection system applications. This model includes physical models for droplet atomization, breakup/coalescence, evaporation, turbulence mixing and gas-phase combustion. Benchmark validation cases for liquid rocket engine chamber combustion conditions will be performed for model validation purpose. Test cases may include shear coaxial, swirl coaxial and impinging injection systems with combinations LOXIH2 or LOXISP-1 propellant injector elements used in rocket engine designs. As a final goal of this project, a well tested parallel CFD performance methodology together with a user's operation description in a final technical report will be reported at the end of the proposed research effort.

  12. Melting and Freezing of Metal Clusters

    NASA Astrophysics Data System (ADS)

    Aguado, Andrés; Jarrold, Martin F.

    2011-05-01

    Recent developments allow heat capacities to be measured for size-selected clusters isolated in the gas phase. For clusters with tens to hundreds of atoms, the heat capacities determined as a function of temperature usually have a single peak attributed to a melting transition. The melting temperatures and latent heats show large size-dependent fluctuations. In some cases, the melting temperatures change by hundreds of degrees with the addition of a single atom. Theory has played a critical role in understanding the origin of the size-dependent fluctuations, and in understanding the properties of the liquid-like and solid-like states. In some cases, the heat capacities have extra features (an additional peak or a dip) that reveal a more complex behavior than simple melting. In this article we provide a description of the methods used to measure the heat capacities and provide an overview of the experimental and theoretical results obtained for sodium and aluminum clusters.

  13. Evaluating statistical and clinical significance of intervention effects in single-case experimental designs: an SPSS method to analyze univariate data.

    PubMed

    Maric, Marija; de Haan, Else; Hogendoorn, Sanne M; Wolters, Lidewij H; Huizenga, Hilde M

    2015-03-01

    Single-case experimental designs are useful methods in clinical research practice to investigate individual client progress. Their proliferation might have been hampered by methodological challenges such as the difficulty applying existing statistical procedures. In this article, we describe a data-analytic method to analyze univariate (i.e., one symptom) single-case data using the common package SPSS. This method can help the clinical researcher to investigate whether an intervention works as compared with a baseline period or another intervention type, and to determine whether symptom improvement is clinically significant. First, we describe the statistical method in a conceptual way and show how it can be implemented in SPSS. Simulation studies were performed to determine the number of observation points required per intervention phase. Second, to illustrate this method and its implications, we present a case study of an adolescent with anxiety disorders treated with cognitive-behavioral therapy techniques in an outpatient psychotherapy clinic, whose symptoms were regularly assessed before each session. We provide a description of the data analyses and results of this case study. Finally, we discuss the advantages and shortcomings of the proposed method. Copyright © 2014. Published by Elsevier Ltd.

  14. A model for a transition from a quasicrystalline to a microcrystalline state

    NASA Astrophysics Data System (ADS)

    Coddens, G.; Launois, P.

    1991-07-01

    We propose a monoatomic model for a quasicrystal transition as observed recently in systems with icosahedral [3] and decagonal [5] symmetry. It is developed here for the case of decagonal symmetry and is inspired by the experimental results on the system Al-Cu-Co-Si [5,6]. The model goes beyond the purely geometrical description by an important physical aspect: the transition mediates through a single atomic jump distance such that only one unique double-well potential has to be invoked to describe it; in conformity with the symmetry there are 10 jump vectors. In the framework of the model, the microcrystalline state is energetically more favourable than a monocrystalline approximant phase. Nous proposons un modèle mono-atomique pour une transition quasicristal-microcristal du type de celles observées récemment dans des systèmes à symétrie icosaédrique [3] et décagonale [5]. Il est développé ici pour la symétrie décagonale et est inspiré par des résultats expérimentaux concernant l'alliage Al-Cu-Co-Si [5,6]. Le modèle va au-delà d'une description purement géometrique par un aspect physique important : la transition se fait via une seule distance de saut inter-atomique de telle sorte q'un seul double-puits de potentiel doit être pris en compte ; conformément à la symétrie, il y a 10 directions de saut. Dans le cadre du modèle, la phase microcristalline est énergétiquement favorisée par rapport à une phase approximante monocristalline.

  15. TASS Model Application for Testing the TDWAP Model

    NASA Technical Reports Server (NTRS)

    Switzer, George F.

    2009-01-01

    One of the operational modes of the Terminal Area Simulation System (TASS) model simulates the three-dimensional interaction of wake vortices within turbulent domains in the presence of thermal stratification. The model allows the investigation of turbulence and stratification on vortex transport and decay. The model simulations for this work all assumed fully-periodic boundary conditions to remove the effects from any surface interaction. During the Base Period of this contract, NWRA completed generation of these datasets but only presented analysis for the neutral stratification runs of that set (Task 3.4.1). Phase 1 work began with the analysis of the remaining stratification datasets, and in the analysis we discovered discrepancies with the vortex time to link predictions. This finding necessitated investigating the source of the anomaly, and we found a problem with the background turbulence. Using the most up to date version TASS with some important defect fixes, we regenerated a larger turbulence domain, and verified the vortex time to link with a few cases before proceeding to regenerate the entire 25 case set (Task 3.4.2). The effort of Phase 2 (Task 3.4.3) concentrated on analysis of several scenarios investigating the effects of closely spaced aircraft. The objective was to quantify the minimum aircraft separations necessary to avoid vortex interactions between neighboring aircraft. The results consist of spreadsheets of wake data and presentation figures prepared for NASA technical exchanges. For these formation cases, NASA carried out the actual TASS simulations and NWRA performed the analysis of the results by making animations, line plots, and other presentation figures. This report contains the description of the work performed during this final phase of the contract, the analysis procedures adopted, and sample plots of the results from the analysis performed.

  16. [In defence of the diagnosis of simple schizophrenia: reflections on a case presentation].

    PubMed

    Martínez Serrano, José; Medina Garrido, María L; Consuegra Sánchez, Rosario; Del Cerro Oñate, Matias; López-Mesa, José L; González Matás, Juana

    2012-01-01

    Since the first case descriptions of dementia praecox (Diem, 1903), the diagnosis of simple schizophrenia has continued to be controversial. The questioning of its descriptive validity and its reliability, as well as its infrequent use, has led to it being eliminated as a sub-type of schizophrenia in the DSM-III. Criteria for the diagnosis of «simple deteriorative disorder» are currently included in the DSM-IV-TR as a disorder requiring more studies for its possible inclusion. An attempt is made, using a clinical case, to perform a historical review of the concept of simple schizophrenia, and at the same what has led to the reflection on the possible reasons for the controversy, and a potential route to resolve it. Using a controversial clinical case, which meets ICD-10 clinical criteria for simple schizophrenia (and those of the DSM-IV-TR for the simple deteriorative disorder), we reflect on the symptoms and diagnostic difficulties. A literature review and update on the subjects was also performed. Our patient highlights, by the absence in the clinical picture of the most obvious positive psychotic symptoms, the tendency by psychiatrists to identify the diagnosis of schizophrenia with the presence of the same, at least at some time during its evolution. The use of neuroimaging tests was useful to assess the level of deterioration and prognosis of the patient. Considering simple schizophrenia in the differential diagnosis of other chronic deteriorative disorders could increase its recognition in the initial phases. The use of neuropsychological function tests, and looking for typical deteriorative patterns of the schizophrenia spectrum, could help to increase the reliability of the diagnosis. Copyright © 2011 SEP y SEPB. Published by Elsevier Espana. All rights reserved.

  17. Description of congenital hand anomalies: a personal view.

    PubMed

    Tonkin, M A

    2006-10-01

    A series of four congenital hand cases exhibiting central clefting are presented. The cases are morphologically similar and exhibit characteristics of both symbrachydactyly and central longitudinal deficiency. The cases demonstrate difficulties in classification by either the IFSSH classification system or the JSSH modification of it. An alternative descriptive approach to classification is suggested.

  18. Microscopic Description of Thermodynamics of Lipid Membrane at Liquid-Gel Phase Transition

    NASA Astrophysics Data System (ADS)

    Kheyfets, B.; Galimzyanov, T.; Mukhin, S.

    2018-05-01

    A microscopic model of the lipid membrane is constructed that provides analytically tractable description of the physical mechanism of the first order liquid-gel phase transition. We demonstrate that liquid-gel phase transition is cooperative effect of the three major interactions: inter-lipid van der Waals attraction, steric repulsion and hydrophobic tension. The model explicitly shows that temperature-dependent inter-lipid steric repulsion switches the system from liquid to gel phase when the temperature decreases. The switching manifests itself in the increase of lateral compressibility of the lipids as the temperature decreases, making phase with smaller area more preferable below the transition temperature. The model gives qualitatively correct picture of abrupt change at transition temperature of the area per lipid, membrane thickness and volume per hydrocarbon group in the lipid chains. The calculated dependence of phase transition temperature on lipid chain length is in quantitative agreement with experimental data. Steric repulsion between the lipid molecules is shown to be the only driver of the phase transition, as van der Waals attraction and hydrophobic tension are weakly temperature dependent.

  19. Pseudochaos and anomalous transport: A study on saw-tooth map

    NASA Astrophysics Data System (ADS)

    Fan, Rong

    The observation of chaotic dynamics in digital filter in late 1980s propelled the interest in piecewise linear map beyond the border of theoretical electrical engineering. Also, during last two decades, various physical models and phenomena, such as stochastic web and sticky orbits, not only broadened our knowledge of chaos but also urged us to further our understanding of meaning of chaos and randomness. In this dissertation, a piecewise linear kicked oscillator model: saw-tooth map, is studied as an example of pseudochaos. Physically, kicked oscillator model describes one-dimensional harmonic oscillator effected by delta-like kicks from external force source at certain fixed frequency. Starting from a special case of global periodicity, numerical investigations were carefully carried out in two cases that deviate from global periodicity. We observe the appearance of stochastic web structure and accompanying erratic dynamical behavior in the system that can't be fully explained by the classical Kolmogorov-Arnold-Moser theorem. Also anomalous transport occurs in both cases. We perform accurate analysis of Poincare recurrences and reconstruct the probability density function of Poincare recurrence times, which suggests a relation between the transport and the Poincare recurrence exponents. Saw-tooth map has non-uniform phase space, in which domains of regular dynamics and domains of chaotic dynamics are intertwined. The large-scale dynamics of the system is hugely impacted by the heterogeneity of the phase space, especially by the existence of hierarchy of periodic islands. We carefully study the characteristics of phase space and numerically compute fractal dimensions of the so-called exceptional set Delta in both cases. Our results suggest that the fractal dimension is strictly less than 2 and that the fractal structures are unifractal rather than multifractal. We present a phenomenological theoretical framework of Fractional Kinetic Equation (FKE) and Renormalization Group of Kinetics (RGK). FKE, which is fractional generalization of the Fokker-Planck-Kolmogorov equation, adopts the fractality of time and space and serves probabilistic description of chaos in Hamiltonian systems. RGK bridges the self-similar structure in phase space and large-scale behavior of the dynamics, and establishes relationships among fractality, transport and Poincare recurrences.

  20. Hypothetical Case and Scenario Description for International Transportation of Spent Nuclear Fuel.

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

    Williams, Adam David; Osborn, Douglas; Jones, Katherine A.

    To support more rigorous analysis on global security issues at Sandia National Laboratories (SNL), there is a need to develop realistic data sets without using "real" data or identifying "real" vulnerabilities, hazards or geopolitically embarrassing shortcomings. In response, an interdisciplinary team led by subject matter experts in SNL's Center for Global Security and Cooperation (CGSC) developed a hypothetical case description. This hypothetical case description assigns various attributes related to international SNF transportation that are representative, illustrative and indicative of "real" characteristics of "real" countries. There is no intent to identify any particular country and any similarity with specific real-world eventsmore » is purely coincidental. To support the goal of this report to provide a case description (and set of scenarios of concern) for international SNF transportation inclusive of as much "real-world" complexity as possible -- without crossing over into politically sensitive or classified information -- this SAND report provides a subject matter expert-validated (and detailed) description of both technical and political influences on the international transportation of spent nuclear fuel. [PAGE INTENTIONALLY LEFT BLANK]« less

  1. Low-noise phase of a two-dimensional active nematic system

    NASA Astrophysics Data System (ADS)

    Shankar, Suraj; Ramaswamy, Sriram; Marchetti, M. Cristina

    2018-01-01

    We consider a collection of self-driven apolar particles on a substrate that organize into an active nematic phase at sufficiently high density or low noise. Using the dynamical renormalization group, we systematically study the two-dimensional fluctuating ordered phase in a coarse-grained hydrodynamic description involving both the nematic director and the conserved density field. In the presence of noise, we show that the system always displays only quasi-long-ranged orientational order beyond a crossover scale. A careful analysis of the nonlinearities permitted by symmetry reveals that activity is dangerously irrelevant over the linearized description, allowing giant number fluctuations to persist although now with strong finite-size effects and a nonuniversal scaling exponent. Nonlinear effects from the active currents lead to power-law correlations in the density field, thereby preventing macroscopic phase separation in the thermodynamic limit.

  2. A New Shape Description Method Using Angular Radial Transform

    NASA Astrophysics Data System (ADS)

    Lee, Jong-Min; Kim, Whoi-Yul

    Shape is one of the primary low-level image features in content-based image retrieval. In this paper we propose a new shape description method that consists of a rotationally invariant angular radial transform descriptor (IARTD). The IARTD is a feature vector that combines the magnitude and aligned phases of the angular radial transform (ART) coefficients. A phase correction scheme is employed to produce the aligned phase so that the IARTD is invariant to rotation. The distance between two IARTDs is defined by combining differences in the magnitudes and aligned phases. In an experiment using the MPEG-7 shape dataset, the proposed method outperforms existing methods; the average BEP of the proposed method is 57.69%, while the average BEPs of the invariant Zernike moments descriptor and the traditional ART are 41.64% and 36.51%, respectively.

  3. Atomistic simulation of cubic and tetragonal phases of U-Mo alloy: Structure and thermodynamic properties

    NASA Astrophysics Data System (ADS)

    Starikov, S. V.; Kolotova, L. N.; Kuksin, A. Yu.; Smirnova, D. E.; Tseplyaev, V. I.

    2018-02-01

    We studied structure and thermodynamic properties of cubic and tetragonal phases of pure uranium and U-Mo alloys using atomistic simulations: molecular dynamics and density functional theory. The main attention was paid to the metastable γ0 -phase that is formed in U-Mo alloys at low temperature. Structure of γ0 -phase is similar to body-centered tetragonal (bct) lattice with displacement of a central atom in the basic cell along [ 001 ] direction. Such displacements have opposite orientations for part of the neighbouring basic cells. In this case, such ordering of the displacements can be designated as antiferro-displacement. Formation of such complex structure may be interpreted through forming of short U-U bonds. At heating, the tetragonal structure transforms into cubic γs -phase, still showing ordering of central atom displacements. With rise in temperature, γs -phase transforms to γ-phase with a quasi body-centered cubic (q-bcc) lattice. The local positions of uranium atoms in γ-phase correspond to γs -phase, however, orientations of the central atom displacements become disordered. Transition from γ0 to γ can be considered as antiferro-to paraelastic transition of order-disorder type. This approach to the structure description of uranium alloy allows to explain a number of unusual features found in the experiments: anisotropy of lattice at low temperature; remarkably high self-diffusion mobility in γ-phase; decreasing of electrical resistivity at heating for some alloys. In addition, important part of this work is the development of new interatomic potential for U-Mo system made with taking into account details of studied structures.

  4. Guidelines for the formulation of Lagrangian stochastic models for particle simulations of single-phase and dispersed two-phase turbulent flows

    NASA Astrophysics Data System (ADS)

    Minier, Jean-Pierre; Chibbaro, Sergio; Pope, Stephen B.

    2014-11-01

    In this paper, we establish a set of criteria which are applied to discuss various formulations under which Lagrangian stochastic models can be found. These models are used for the simulation of fluid particles in single-phase turbulence as well as for the fluid seen by discrete particles in dispersed turbulent two-phase flows. The purpose of the present work is to provide guidelines, useful for experts and non-experts alike, which are shown to be helpful to clarify issues related to the form of Lagrangian stochastic models. A central issue is to put forward reliable requirements which must be met by Lagrangian stochastic models and a new element brought by the present analysis is to address the single- and two-phase flow situations from a unified point of view. For that purpose, we consider first the single-phase flow case and check whether models are fully consistent with the structure of the Reynolds-stress models. In the two-phase flow situation, coming up with clear-cut criteria is more difficult and the present choice is to require that the single-phase situation be well-retrieved in the fluid-limit case, elementary predictive abilities be respected and that some simple statistical features of homogeneous fluid turbulence be correctly reproduced. This analysis does not address the question of the relative predictive capacities of different models but concentrates on their formulation since advantages and disadvantages of different formulations are not always clear. Indeed, hidden in the changes from one structure to another are some possible pitfalls which can lead to flaws in the construction of practical models and to physically unsound numerical calculations. A first interest of the present approach is illustrated by considering some models proposed in the literature and by showing that these criteria help to assess whether these Lagrangian stochastic models can be regarded as acceptable descriptions. A second interest is to indicate how future developments can be safely built, which is also relevant for stochastic subgrid models for particle-laden flows in the context of Large Eddy Simulations.

  5. Guidelines for the formulation of Lagrangian stochastic models for particle simulations of single-phase and dispersed two-phase turbulent flows

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

    Minier, Jean-Pierre, E-mail: Jean-Pierre.Minier@edf.fr; Chibbaro, Sergio; Pope, Stephen B.

    In this paper, we establish a set of criteria which are applied to discuss various formulations under which Lagrangian stochastic models can be found. These models are used for the simulation of fluid particles in single-phase turbulence as well as for the fluid seen by discrete particles in dispersed turbulent two-phase flows. The purpose of the present work is to provide guidelines, useful for experts and non-experts alike, which are shown to be helpful to clarify issues related to the form of Lagrangian stochastic models. A central issue is to put forward reliable requirements which must be met by Lagrangianmore » stochastic models and a new element brought by the present analysis is to address the single- and two-phase flow situations from a unified point of view. For that purpose, we consider first the single-phase flow case and check whether models are fully consistent with the structure of the Reynolds-stress models. In the two-phase flow situation, coming up with clear-cut criteria is more difficult and the present choice is to require that the single-phase situation be well-retrieved in the fluid-limit case, elementary predictive abilities be respected and that some simple statistical features of homogeneous fluid turbulence be correctly reproduced. This analysis does not address the question of the relative predictive capacities of different models but concentrates on their formulation since advantages and disadvantages of different formulations are not always clear. Indeed, hidden in the changes from one structure to another are some possible pitfalls which can lead to flaws in the construction of practical models and to physically unsound numerical calculations. A first interest of the present approach is illustrated by considering some models proposed in the literature and by showing that these criteria help to assess whether these Lagrangian stochastic models can be regarded as acceptable descriptions. A second interest is to indicate how future developments can be safely built, which is also relevant for stochastic subgrid models for particle-laden flows in the context of Large Eddy Simulations.« less

  6. Semiempirical models for description of shear modulus in wide ranges of temperatures and pressures of shock compression

    NASA Astrophysics Data System (ADS)

    El'Kin, V. M.; Mikhailov, V. N.; Mikhailova, T. Yu.

    2011-12-01

    In this paper, we discuss the potentials of the Steinberg-Cochran-Guinan (SCG) and Burakovsky-Preston (BP) models for the description of the shear-modulus behavior at temperatures and pressures that arise behind the shock-wave front. A modernized variant of the SCG model is suggested, which reduces to the introduction of a free parameter and the representation of the model in the volume-temperature coordinates (( V, T) model). A systematic comparison is performed of all three models of shear modulus with experimental data and data of ab initio calculations for metals such as Al, Be, Cu, K, Na, Mg, Mo, W, and Ta in a wide range of pressures. In addition, for Al, Cu, Mo, W, and Ta there is performed a comparison with the known temperature dependences of the shear modulus and with the results of measurements of the velocities of longitudinal sound behind the shock-wave front. It is shown that in the original form the SCG and BP models give overestimated values of the shear modulus as compared to the data of ab initio calculations and shock-wave experiments. The ( V, T) model, due to the use of a free parameter, makes it possible to optimally describe the totality of experimental and calculated data. The same result is achieved in the case of the BP model after a redefining of its initial parameters. The adequate description of the shear modulus in the range of high intermediate pressures characteristic of the solid-phase states behind the shock-wave front is accompanied in both cases by the violation of the correct asymptotic behavior of the shear modulus at ultrahigh compressions which is originally laid into the SCG and BP models.

  7. 47 CFR 90.743 - Renewal expectancy.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... showing must include: (1) A description of its current service in terms of geographic coverage and... relate to any matter described in this paragraph. (c) Phase I non-nationwide licensees have license terms... authorization in order to receive a renewal expectancy. Phase I nationwide licensees and all Phase II licensees...

  8. 47 CFR 90.743 - Renewal expectancy.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... showing must include: (1) A description of its current service in terms of geographic coverage and... relate to any matter described in this paragraph. (c) Phase I non-nationwide licensees have license terms... authorization in order to receive a renewal expectancy. Phase I nationwide licensees and all Phase II licensees...

  9. An Introduction to Phase-Sensitive Amplifiers: An Inexpensive Student Instrument

    ERIC Educational Resources Information Center

    Temple, Paul A.

    1975-01-01

    Discusses the principle of operation of phase-sensitive amplifiers. Gives three examples, suitable for undergraduate laboratory use, of the use of phase-sensitive, or "lock-in" amplifiers. Concludes with a description of an inexpensive lock-in amplifier which has an overall voltage gain of 1000. (Author/MLH)

  10. Circumstances of Trauma and Accidents in Children: A Thesaurus-based Survey

    PubMed

    Séjourné, Claire; Philbois, Olivier; Vercherin, Paul; Patural, Hugues

    2016-11-25

    Introduction : Injuries and accidents are major causes of morbidity and mortality in children in France. Identification and description of the mechanisms of accidents are essential to develop adapted prevention methods. For this purpose, a specific thesaurus of ICD-10 codes relating to the circumstances of trauma and accidents in children was created in the French Loire department. The objective of this study was to evaluate the relevance and acceptability of the thesaurus in the pediatric emergency unit of Saint-Etienne university hospital.Material and Methods : This study was conducted in two phases. The first, longitudinal phase was conducted over three periods between May and October 2014 to compare codings by emergency room physicians before using the thesaurus with those defined on the basis of the thesaurus. The second phase retrospectively compared coding in July and August 2014 before introduction of the thesaurus with thesaurus-based coding in July and August 2015.Results : The first phase showed a loss of more than half of the information without the thesaurus. The circumstances of trauma can be described by an appropriate code in more than 90% of cases. The second phase showed a 13% increase in coding of the circumstances of trauma, which nevertheless remains insufficient.Discussion : The thesaurus facilitates coding and generally meets the coding physician’s expectations and should be used in large-scale epidemiological surveys.

  11. The second-order theory of electromagnetic hot ion beam instabilities. [in interplanetary magnetic field

    NASA Technical Reports Server (NTRS)

    Gary, S. P.; Tokar, R. L.

    1985-01-01

    The present investigation is concerned with the application of a second-order theory for electromagnetic instabilities in a collisionless plasma to two modes which resonate with hot ion beams. The application of the theory is strictly limited to the linear growth phase. However, the application of the theory may be extended to obtain a description of the beam at postsaturation if the wave-beam resonance is sufficiently broad in velocity space. Under the considered limitations, it is shown that, as in the cold beam case, the fluctuating fields do not gain appreciable momentum and that the primary exchange of momentum is between the beam and main component.

  12. On the topology of the inflaton field in minimal supergravity models

    NASA Astrophysics Data System (ADS)

    Ferrara, Sergio; Fré, Pietro; Sorin, Alexander S.

    2014-04-01

    We consider global issues in minimal supergravity models where a single field inflaton potential emerges. In a particular case we reproduce the Starobinsky model and its description dual to a certain formulation of R + R 2 supergravity. For definiteness we confine our analysis to spaces at constant curvature, either vanishing or negative. Five distinct models arise, two flat models with respectively a quadratic and a quartic potential and three based on the space where its distinct isometries, elliptic, hyperbolic and parabolic are gauged. Fayet-Iliopoulos terms are introduced in a geometric way and they turn out to be a crucial ingredient in order to describe the de Sitter inflationary phase of the Starobinsky model.

  13. [Imaging origins and characteristics analysis of acute and chronic aspiration pneumonia].

    PubMed

    Wang, Kang; Li, Ming; Wang, Xiongbiao; Qin, Jianmin; Wang, Zhi; Zhao, Zehua; Qin, Le; Hua, Yanqing

    2014-11-11

    To discuss about the pathologic and imaging origins and characteristics of CT scaning and X-ray radiography for acute and chronic aspiration pneumonia. Imaging data from 30 patients with aspiration pneumonia were retrospectively analyzed, CT scaning was performed in 27 patients, which PMVR reconstruction was performed in 21 cases;3 exammed by X-ray with 2 used by esophagography. Opaque bodies were detected in trachea by CT scaning in 12 patients.7 patients in acute phase rapidly developed into acute respiratory distress syndrome(ARDS). CT signs of 30 patients with acute and chronic aspiration pneumonia included: centrilobular nodules were detected in 2 cases with acute phase, 4 cases with subacute phase and 4 cases with chronic phase; the imaging of ground glass opacity were detected in 9 cases with acute phase, 2 cases with subacute phase and 3 cases with chronic phase; the imaging of bronchiectasis was detected in 8 cases with chronic phase, which mucilage embolism was detected in 3 of 8 cases; the imaging of atelectasis was detected in 6 cases with chronic phase; the imaging of sheeted consolidation was detected in 5 cases with chronic phase, 8 case with acute phase; the imaging of interstitial fibrosis was detected in 3 cases with chronic phase. Lesions of inferior lobe of right lung were detected in 9 cases with chronic phase, 4 cases with subacute phase, 11 case with acute phase;lesions of inferior lobe of left lung were detected in 6 cases with chronic phase and 3 cases with subacute group, 11 case with acute phase. The imaging features of acute and chronic aspiration pneumonia overlap with GGO and centrilobular nodules in every group. While the imaging features of atelectasis, bronchiectasis or mucilage embolism are found in chronic phase. The chest CT scaning may accurately evaluate the dynamic change of aspiration pneumonia.

  14. Application of the string method to the study of critical nuclei in capillary condensation.

    PubMed

    Qiu, Chunyin; Qian, Tiezheng; Ren, Weiqing

    2008-10-21

    We adopt a continuum description for liquid-vapor phase transition in the framework of mean-field theory and use the string method to numerically investigate the critical nuclei for capillary condensation in a slit pore. This numerical approach allows us to determine the critical nuclei corresponding to saddle points of the grand potential function in which the chemical potential is given in the beginning. The string method locates the minimal energy path (MEP), which is the most probable transition pathway connecting two metastable/stable states in configuration space. From the MEP, the saddle point is determined and the corresponding energy barrier also obtained (for grand potential). Moreover, the MEP shows how the new phase (liquid) grows out of the old phase (vapor) along the most probable transition pathway, from the birth of a critical nucleus to its consequent expansion. Our calculations run from partial wetting to complete wetting with a variable strength of attractive wall potential. In the latter case, the string method presents a unified way for computing the critical nuclei, from film formation at solid surface to bulk condensation via liquid bridge. The present application of the string method to the numerical study of capillary condensation shows the great power of this method in evaluating the critical nuclei in various liquid-vapor phase transitions.

  15. From containment to community: Trigger points from the London pandemic (H1N1) 2009 influenza incident response.

    PubMed

    Balasegaram, S; Glasswell, A; Cleary, V; Turbitt, D; McCloskey, B

    2011-02-01

    In the UK, during the first wave of pandemic (H1N1) 2009 influenza, a national 'containment' strategy was employed from 25 April to 2 July 2009, with case finding, treatment of cases, contact tracing and prophylaxis of close contacts. The aim of the strategy was to delay the introduction and spread of pandemic flu in the UK, provide a better understanding of the course of the novel disease, and thereby allow more time for the development of treatment and vaccination options. Descriptive study of the management of the containment phase of pandemic (H1N1) 2009 influenza. Analysis of data reported to the London Flu Response Centre (LFRC). The average number of telephone calls and faxes per day from health professionals before 15 June 2009 was 188, but this started to rise from 363 on 12 June, to 674 on 15 June, and peaked on 22 June at 2206 calls. The number of cases confirmed [by pandemic (H1N1) 2009 influenza specific H1 and N1 polymerase chain reaction] in London rose to a peak of 200 cases per day. There were widespread school outbreaks reporting large numbers of absences with influenza-like illnesses. Activity in the LFRC intensified to a point where London was declared a 'hot spot' for pandemic (H1N1) 2009 influenza on 19 June 2009 because of sustained community transmission. The local incident response was modified to the 'outbreak management phase' of the containment phase. The sharp rise in the number of telephone calls and the rise in school outbreaks appeared to be trigger points for community transmission. These indicators should inform decisions on modifying public health strategy in pandemic situations. Copyright © 2010 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  16. Issues in reflection and debriefing: how nurse educators structure experiential activities.

    PubMed

    Brackenreg, Jenni

    2004-12-01

    Experiential learning is particularly useful in vocational education programs where theory needs to be linked to practice. Although experiential learning is often advocated in nursing education and the importance of debriefing and reflection is almost always espoused, the focus in the literature has tended to be on detailed descriptions of the action phase with little close analysis of how the reflective phase is facilitated. The Lewinian model described by Kolb [Experiential Learning. Experience as Source of Learning and Development, Prentice-Hall, New Jersey, 1984] and the structuring approach suggested by Thiagarajan [Experiential Learning Packages, Prentice-Hall, Englewood Cliffs, NJ, 1980] have been used as the theoretical context for an exploration of how nurse teachers describe their facilitation of the debriefing and reflective phases of experiential learning activities. Explication of the entire planned experiential learning experience is important for increasing the chances of the student being able to close the experiential learning loop. The more covert reflective phases for facilitating experiential learning are crucial and if neglected, or inexpertly and insensitively handled, may at best lead to poor learning outcomes or at worst lead to emotional damage and ;unfinished business' for the student. Interviews with eight experienced university educators elicited descriptions of how they constructed experiential activities with special reference to their descriptions of how the debriefing or reflective phases were structured.

  17. Thermodynamic Description of the Quaternary Ag-Bi-Cu-Sn System

    NASA Astrophysics Data System (ADS)

    Gierlotka, Wojciech

    2018-01-01

    Lead-free soldering is an important part of electronic devices production. New lead-free solders that replace classical Sn-37Pb solder are still under development. Thermodynamic modeling makes the development process faster, cheaper and more environmentally friendly due to predictions of phases stabilities and phases transformations. In this work, the thermodynamic description of quaternary Ag-Bi-Cu-Sn system is presented. The thermodynamic assessment of promising lead-free quaternary solder was prepared using the Calphad approach. A good agreement between available experimental data and calculation was found.

  18. Flow induced vibrations in the SSME injector heads

    NASA Technical Reports Server (NTRS)

    Lepore, Frank A.

    1991-01-01

    A description is given of the flowfield in the Space Shuttle Main Engine (SSME) powerhead, the mechanisms which control flow-induced vibrations, and previous experimental work. An in-depth description is given of the development phase of the program , which includes the analysis, design, and fabrication of liquid oxygen (LOX) posts models used in the experimental phase, as well as test facilities, equipment, and procedures used. Also covered is the experimental data analysis, which includes overall steady state powerhead flowfield as well as the high frequency response of the LOX posts.

  19. The development of novel simulation methodologies and intermolecular potential models for real fluids

    NASA Astrophysics Data System (ADS)

    Errington, Jeffrey Richard

    This work focuses on the development of intermolecular potential models for real fluids. United-atom models have been developed for both non-polar and polar fluids. The models have been optimized to the vapor-liquid coexistence properties. Histogram reweighting techniques were used to calculate phase behavior. The Hamiltonian scaling grand canonical Monte Carlo method was developed to enable the determination of thermodynamic properties of several related Hamiltonians from a single simulation. With this method, the phase behavior of variations of the Buckingham exponential-6 potential was determined. Reservoir grand canonical Monte Carlo simulations were developed to simulate molecules with complex architectures and/or stiff intramolecular constraints. The scheme is based on the creation of a reservoir of ideal chains from which structures are selected for insertion during a simulation. New intermolecular potential models have been developed for water, the n-alkane homologous series, benzene, cyclohexane, carbon dioxide, ammonia and methanol. The models utilize the Buckingham exponential-6 potential to model non-polar interactions and point charges to describe polar interactions. With the exception of water, the new models reproduce experimental saturated densities, vapor pressures and critical parameters to within a few percent. In the case of water, we found a set of parameters that describes the phase behavior better than other available point charge models while giving a reasonable description of the liquid structure. The mixture behavior of water-hydrocarbon mixtures has also been examined. The Henry's law constants of methane, ethane, benzene and cyclohexane in water were determined using Widom insertion and expanded ensemble techniques. In addition the high-pressure phase behavior of water-methane and water-ethane systems was studied using the Gibbs ensemble method. The results from this study indicate that it is possible to obtain a good description of the phase behavior of pure components using united-atom models. The mixture behavior of non-polar systems, including highly asymmetric components, was in good agreement with experiment. The calculations for the highly non-ideal water-hydrocarbon mixtures reproduced experimental behavior with varying degrees of success. The results indicate that multibody effects, such as polarizability, must be taken into account when modeling mixtures of polar and non-polar components.

  20. Innovative technology: Slurry-phase biodegradation. Fact sheet (Final)

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

    Not Available

    1989-11-01

    The fact sheet provides technology description, site characteristics affecting treatment feasibility, technology considerations, and technology status for Slurry Phase Biodegradation (SPB). The sheet describes how SPB is potentially effective in treating various organic contaminants.

  1. High cost sharing and specialty drug initiation under Medicare Part D: a case study in patients with newly diagnosed chronic myeloid leukemia.

    PubMed

    Doshi, Jalpa A; Li, Pengxiang; Huo, Hairong; Pettit, Amy R; Kumar, Rishab; Weiss, Brenda M; Huntington, Scott F

    2016-03-01

    Specialty drugs often offer medical advances but are frequently subject to high cost sharing. This is particularly true with Medicare Part D, where after meeting a deductible, patients without low-income subsidies (non-LIS) typically face 25% to 33% coinsurance (initial coverage phase with "specialty tier" cost sharing), followed by ~50% coinsurance (coverage gap phase), and then 5% coinsurance (catastrophic phase). Yet, no studies have examined the impact of such high cost sharing on specialty drug initiation under Part D. Oral tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of chronic myeloid leukemia (CML), making it an apt case study. A retrospective claims-based analysis utilizing 2011 to 2013 100% Medicare claims. TKI initiation rates and time to initiation were compared between fee-for-service non-LIS Part D patients newly diagnosed with CML and their LIS counterparts who faced nominal cost sharing of ≤ $5. The first 30-day TKI fill "straddled" benefit phases, for a mean out-of-pocket cost of $2600 or more for non-LIS patients. Non-LIS patients were less likely than LIS patients to have a TKI claim within 6 months of diagnosis (45.3% vs 66.9%; P < .001) and those initiating a TKI took twice as long to fill it (mean = 50.9 vs 23.7 days; P < .001). Cox regressions controlling for sociodemographic, clinical, and plan characteristics confirmed descriptive findings (hazard ratio, 0.59; 95% CI, 0.45-0.76). Extensive sensitivity analyses confirmed the robustness of our findings. High cost sharing was associated with reduced and/or delayed initiation of TKIs. We discuss policy strategies to reduce current financial barriers that adversely impact access to critical therapies under Medicare Part D.

  2. Perforation and mortality after cleansing enema for acute constipation are not rare but are preventable.

    PubMed

    Niv, Galia; Grinberg, Tamar; Dickman, Ram; Wasserberg, Nir; Niv, Yaron

    2013-01-01

    Constipation is a common complaint, frequently treated with cleansing enema. Enemas can be very effective but may cause serious adverse events, such as perforation or metabolic derangement. Our aim was to evaluate the outcome of the use of cleansing enema for acute constipation and to assess adverse events within 30 days of therapy. We performed a two-phase study: an initial retrospective and descriptive study in 2010, followed by a prospective study after intervention, in 2011. According to the results of the first phase we established guidelines for the treatment of constipation in the Emergency Department and then used these in the second phase. There were 269 and 286 cases of severe constipation in the first and second periods of the study, respectively. In the first study period, only Fleet® Enema was used, and in the second, this was changed to Easy Go enema (free of sodium phosphate). There was a 19.2% decrease in the total use of enema, in the second period of the study (P < 0.0001). Adverse events and especially, the perforation rate and the 30-day mortality in patients with constipation decreased significantly in the second phase: 3 (1.4%) versus 0 (P = 0.0001) and 8 (3.9%) versus 2 (0.7%) (P = 0.0001), for perforation and death in the first and second period of the study, respectively. Enema for the treatment of acute constipation is not without adverse events, especially in the elderly, and should be applied carefully. Perforation, hyperphosphatemia (after Fleet Enema), and sepsis may cause death in up to 4% of cases. Guidelines for the treatment of acute constipation and for enema administration are urgently needed.

  3. Perforation and mortality after cleansing enema for acute constipation are not rare but are preventable

    PubMed Central

    Niv, Galia; Grinberg, Tamar; Dickman, Ram; Wasserberg, Nir; Niv, Yaron

    2013-01-01

    Objectives Constipation is a common complaint, frequently treated with cleansing enema. Enemas can be very effective but may cause serious adverse events, such as perforation or metabolic derangement. Our aim was to evaluate the outcome of the use of cleansing enema for acute constipation and to assess adverse events within 30 days of therapy. Methods We performed a two-phase study: an initial retrospective and descriptive study in 2010, followed by a prospective study after intervention, in 2011. According to the results of the first phase we established guidelines for the treatment of constipation in the Emergency Department and then used these in the second phase. Results There were 269 and 286 cases of severe constipation in the first and second periods of the study, respectively. In the first study period, only Fleet® Enema was used, and in the second, this was changed to Easy Go enema (free of sodium phosphate). There was a 19.2% decrease in the total use of enema, in the second period of the study (P < 0.0001). Adverse events and especially, the perforation rate and the 30-day mortality in patients with constipation decreased significantly in the second phase: 3 (1.4%) versus 0 (P = 0.0001) and 8 (3.9%) versus 2 (0.7%) (P = 0.0001), for perforation and death in the first and second period of the study, respectively. Conclusion Enema for the treatment of acute constipation is not without adverse events, especially in the elderly, and should be applied carefully. Perforation, hyperphosphatemia (after Fleet Enema), and sepsis may cause death in up to 4% of cases. Guidelines for the treatment of acute constipation and for enema administration are urgently needed. PMID:23658492

  4. Branch point reconstructors for discontinuous light phase functions

    NASA Astrophysics Data System (ADS)

    Le Bigot, Eric O.; Wild, Walter J.; Kibblewhite, Edward J.

    1998-09-01

    The study of phase discontinuities caused by atmospheric turbulence is a recent research topic; their study might yield significant improvements in high-quality adaptive optics systems, laser weapons and laser communication. We present in this paper an introduction to discontinuities in the light phase. We also provide a geometrical description of phase discontinuities, a study of their effect on Hartmann-Shack sensor measurements, as well as algorithms for measuring discontinuous light phases and the position of phase discontinuities.

  5. FINAL PROJECT REPORT - EVALUATION AND TESTING OF HTGR REACTOR BUILDING RESPONSE TO DEPRESSURIZATION ACCIDENTS

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

    ALLIANCE LIMITED, NGNP INDUSTRY

    This report provides a description of the project, summarizes each phase of the project, and ends with project conclusions. In addition, the report contains a descriptive index of the technical reports generated during the course of the project.

  6. Phase shifts in the Fourier spectra of phase gratings and phase grids: an application for one-shot phase-shifting interferometry.

    PubMed

    Toto-Arellano, Noel-Ivan; Rodriguez-Zurita, Gustavo; Meneses-Fabian, Cruz; Vazquez-Castillo, Jose F

    2008-11-10

    Among several techniques, phase shifting interferometry can be implemented with a grating used as a beam divider to attain several interference patterns around each diffraction order. Because each pattern has to show a different phase-shift, a suitable shifting technique must be employed. Phase gratings are attractive to perform the former task due to their higher diffraction efficiencies. But as is very well known, the Fourier coefficients of only-phase gratings are integer order Bessel functions of the first kind. The values of these real-valued functions oscillate around zero, so they can adopt negative values, thereby introducing phase shifts of pi at certain diffraction orders. Because this almost trivial fact seems to have been overlooked in the literature regarding its practical implications, in this communication such phase shifts are stressed in the description of interference patterns obtained with grating interferometers. These patterns are obtained by placing two windows in the object plane of a 4f system with a sinusoidal grating/grid in the Fourier plane. It is shown that the corresponding experimental observations of the fringe modulation, as well as the corresponding phase measurements, are all in agreement with the proposed description. A one-shot phase shifting interferometer is finally proposed taking into account these properties after proper incorporation of modulation of polarization.

  7. Retrospective study of sonographic findings in bone involvement associated with rotator cuff calcific tendinopathy: preliminary results of a case series*

    PubMed Central

    Nogueira-Barbosa, Marcello H.; Gregio-Junior, Everaldo; Lorenzato, Mario Muller

    2015-01-01

    Objective The present study was aimed at investigating bone involvement secondary to rotator cuff calcific tendonitis at ultrasonography. Materials and Methods Retrospective study of a case series. The authors reviewed shoulder ultrasonography reports of 141 patients diagnosed with rotator cuff calcific tendonitis, collected from the computer-based data records of their institution over a four-year period. Imaging findings were retrospectively and consensually analyzed by two experienced musculoskeletal radiologists looking for bone involvement associated with calcific tendonitis. Only the cases confirmed by computed tomography were considered for descriptive analysis. Results Sonographic findings of calcific tendinopathy with bone involvement were observed in 7/141 (~ 5%) patients (mean age, 50.9 years; age range, 42-58 years; 42% female). Cortical bone erosion adjacent to tendon calcification was the most common finding, observed in 7/7 cases. Signs of intraosseous migration were found in 3/7 cases, and subcortical cysts in 2/7 cases. The findings were confirmed by computed tomography. Calcifications associated with bone abnormalities showed no acoustic shadowing at ultrasonography, favoring the hypothesis of resorption phase of the disease. Conclusion Preliminary results of the present study suggest that ultrasonography can identify bone abnormalities secondary to rotator cuff calcific tendinopathy, particularly the presence of cortical bone erosion. PMID:26811551

  8. WINCLR: a Computer Code for Heat Transfer and Clearance Calculation in a Compressor

    NASA Technical Reports Server (NTRS)

    Bose, T. K.; Murthy, S. N. B.

    1994-01-01

    One of the concerns during inclement weather operation of aircraft in rain and hail storm conditions is the nature and extent of changes in compressor casing clearance. An increase in clearance affects efficiency while a decrease may cause blade rubbing with the casing. The change in clearance is the result of geometrical dimensional changes in the blades, the casing and the rotor due to heat transfer between those parts and the two-phase working fluid. The heat transfer interacts nonlinearly with the performance of the compressor, and, therefore, the determination of clearance changes necessitates a simultaneous determination of change in performance of the compressor. A computer code the WINCLR has been designed for the determination of casing clearance, that is operated interactively with the PURDU-WINCOF I code designed previously for determining the performance of a compressor. A detailed description of the WINCLR code is provided in a companion report. The current report provides details of the code with an illustrative example of application to the case of a multistage compressor. It is found in the example case that under given ingestion and operational conditions, it is possible for a compressor to undergo changes in performance in the front stages and rubbing in the back stages.

  9. Retrospective study of sonographic findings in bone involvement associated with rotator cuff calcific tendinopathy: preliminary results of a case series.

    PubMed

    Nogueira-Barbosa, Marcello H; Gregio-Junior, Everaldo; Lorenzato, Mario Muller

    2015-01-01

    The present study was aimed at investigating bone involvement secondary to rotator cuff calcific tendonitis at ultrasonography. Retrospective study of a case series. The authors reviewed shoulder ultrasonography reports of 141 patients diagnosed with rotator cuff calcific tendonitis, collected from the computer-based data records of their institution over a four-year period. Imaging findings were retrospectively and consensually analyzed by two experienced musculoskeletal radiologists looking for bone involvement associated with calcific tendonitis. Only the cases confirmed by computed tomography were considered for descriptive analysis. Sonographic findings of calcific tendinopathy with bone involvement were observed in 7/141 (~ 5%) patients (mean age, 50.9 years; age range, 42-58 years; 42% female). Cortical bone erosion adjacent to tendon calcification was the most common finding, observed in 7/7 cases. Signs of intraosseous migration were found in 3/7 cases, and subcortical cysts in 2/7 cases. The findings were confirmed by computed tomography. Calcifications associated with bone abnormalities showed no acoustic shadowing at ultrasonography, favoring the hypothesis of resorption phase of the disease. Preliminary results of the present study suggest that ultrasonography can identify bone abnormalities secondary to rotator cuff calcific tendinopathy, particularly the presence of cortical bone erosion.

  10. Phases and phase transition in insoluble and adsorbed monolayers of amide amphiphiles: Specific characteristics of the condensed phases.

    PubMed

    Vollhardt, D

    2015-08-01

    For understanding the role of amide containing amphiphiles in inherently complex biological processes, monolayers at the air-water interface are used as simple biomimetic model systems. The specific characteristics of the condensed phases and phase transition in insoluble and adsorbed monolayers of amide amphiphiles are surveyed to highlight the effect of the chemical structure of the amide amphiphiles on the interfacial interactions in model monolayers. The mesoscopic topography and/or two-dimensional lattice structures of selected amino acid amphiphiles, amphiphilic N-alkylaldonamide, amide amphiphiles with specific tailored headgroups, such as amide amphiphiles based on derivatized ethanolamine, e.g. acylethanolamines (NAEs) and N-,O-diacylethanolamines (DAEs) are presented. Special attention is devoted the dominance of N,O-diacylated ethanolamine in mixed amphiphilic acid amide monolayers. The evidence that a first order phase transition can occur in adsorption layers and that condensed phase domains of mesoscopic scale can be formed in adsorption layers was first obtained on the basis of the experimental characteristics of a tailored amide amphiphile. New thermodynamic and kinetic concepts for the theoretical description of the characteristics of amide amphiphile's monolayers were developed. In particular, the equation of state for Langmuir monolayers generalized for the case that one, two or more phase transitions occur, and the new theory for phase transition in adsorbed monolayers are experimentally confirmed at first by amide amphiphile monolayers. Despite the significant progress made towards the understanding the model systems, these model studies are still limited to transfer the gained knowledge to biological systems where the fundamental physical principles are operative in the same way. The study of biomimetic systems, as described in this review, is only a first step in this direction. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. A DMPA Langmuir monolayer study: from gas to solid phase. An atomistic description by molecular dynamics Simulation.

    PubMed

    Giner-Casares, J J; Camacho, L; Martín-Romero, M T; Cascales, J J López

    2008-03-04

    In this work, a DMPA Langmuir monolayer at the air/water interface was studied by molecular dynamics simulations. Thus, an atomistic picture of a Langmuir monolayer was drawn from its expanded gas phase to its final solid condensed one. In this sense, some properties of monolayers that were traditionally poorly or even not reproduced in computer simulations, such as lipid domain formation or pressure-area per lipid isotherm, were properly reproduced in this work. Thus, the physical laws that control the lipid domain formation in the gas phase and the structure of lipid monolayers from the gas to solid condensed phase were studied. Thanks to the atomistic information provided by the molecular dynamics simulations, we were able to add valuable information to the experimental description of these processes and to access experimental data related to the lipid monolayers in their expanded phase, which is difficult or inaccessible to study by experimental techniques. In this sense, properties such as lipids head hydration and lipid structure were studied.

  12. Continuum theory for cluster morphologies of soft colloids.

    PubMed

    Kosmrlj, A; Pauschenwein, G J; Kahl, G; Ziherl, P

    2011-06-09

    We introduce a continuum description of the thermodynamics of colloids with a core-corona architecture. In the case of thick coronas, their overlap can be treated approximately by replacing the exact one-particle density distribution by a suitably shaped step profile, which provides a convenient way of modeling the spherical, columnar, lamellar, and inverted cluster morphologies predicted by numerical simulations and the more involved theories. We use the model to study monodisperse particles with the hard-core/square-shoulder pair interaction as the simplest representatives of the core-corona class. We derive approximate analytical expressions for the enthalpies of the cluster morphologies which offer a clear insight into the mechanisms at work, and we calculate the lattice spacing and the cluster size for all morphologies of the phase sequence as well as the phase-transition pressures. By comparing the results with the exact crystalline minimum-enthalpy configurations, we show that the accuracy of the theory increases with shoulder width. We discuss possible extensions of the theory that could account for the finite-temperature effects.

  13. New type of synchronization of oscillators with hard excitation

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

    Kovaleva, M. A., E-mail: margo.kovaleva@gmail.com; Manevich, L. I., E-mail: manevichleonid3@gmail.com; Pilipchuk, V. N.

    2013-08-15

    It is shown that stable limiting cycles corresponding to nonlinear beats with complete energy exchange between oscillators can exist in a system of two weakly coupled active oscillators (generators). The oscillatory regime of this type, which implements a new type of synchronization in an active system, is an alternative to the well-studied synchronization in a regime close to a nonlinear normal mode. In this case, the ranges of dissipative parameters corresponding to different types of synchronization do not intersect. The analytic description of attractors revealed in analysis is based on the concept of limiting phase trajectories, which was developed earliermore » by one of the authors for conservative systems. A transition (in the parametric space) from the complete energy exchange between oscillators to predominant localization of energy in one of the oscillators can be naturally described using this concept. The localized normal mode is an attractor in the range of parameters in which neither the limiting phase trajectory nor any of the collective normal modes is an attractor.« less

  14. A Model for Displacements Between Parallel Plates That Shows Change of Type from Hyperbolic to Elliptic

    NASA Astrophysics Data System (ADS)

    Shariati, Maryam; Yortsos, Yannis; Talon, Laurent; Martin, Jerome; Rakotomalala, Nicole; Salin, Dominique

    2003-11-01

    We consider miscible displacement between parallel plates, where the viscosity is a function of the concentration. By selecting a piece-wise representation, the problem can be considered as ``three-phase'' flow. Assuming a lubrication-type approximation, the mathematical description is in terms of two quasi-linear hyperbolic equations. When the mobility of the middle phase is smaller than its neighbors, the system is genuinely hyperbolic and can be solved analytically. However, when it is larger, an elliptic region develops. This change-of-type behavior is for the first time proved here based on sound physical principles. Numerical solutions with a small diffusion are presented. Good agreement is obtained outside the elliptic region, but not inside, where the numerical results show unstable behavior. We conjecture that for the solution of the real problem in the mixed-type case, the full higher-dimensionality problem must be considered inside the elliptic region, in which the lubrication (parallel-flow) approximation is no longer appropriate. This is discussed in a companion presentation.

  15. [An epidemiological study of the distinct histological types of cutaneous melanoma in relation to other variables of the disease].

    PubMed

    Morales Suárez-Varela, M M; Llopis González, A; Lacasaña Navarro, M; Agudo Ferrándiz, J; Segarra Castelló, L

    1992-03-01

    A retrospective descriptive study is carried out from the whole of malignant cutaneous melanomas diagnosed at the Dermatology Service of the General University Hospital of Valencia (HGUV), during the period 1977-1987, in which the 80% of the whole of the cases in the province of Valencia are diagnosed, specifically 247 patients are studied. The ones located on the leg stand out 21%, followed by posterior thorax 14% and face 12%. Likewise, differences statistically significant p less than 0.001 are observed among the distinct histological types of cutaneous malignant melanoma (CMM) with regard to the depth of the tumours invasion (measured in Clark levels and millimetres of depth), mitosis/area, mitosis index and prognosis index. Being the lentigo of malignant melanoma (LMM) the histological type diagnosed in earlier phases, hence it is the most capable variant of curative treatment, just the opposite that happens to the nodular malignant melanoma (NMM), that is normally diagnosed in more advanced phases of the illness.

  16. Design of a case management model for people with chronic disease (Heart Failure and COPD). Phase I: modeling and identification of the main components of the intervention through their actors: patients and professionals (DELTA-icE-PRO Study).

    PubMed

    Morales-Asencio, Jose M; Martin-Santos, Francisco J; Morilla-Herrera, Juan C; Fernández-Gallego, Magdalena Cuevas; Celdrán-Mañas, Miriam; Navarro-Moya, Francisco J; Rodríguez-Salvador, Maria M; Muñoz-Ronda, Francisco J; Gonzalo-Jiménez, Elena; Carrasco, Almudena Millán

    2010-12-02

    Chronic diseases account for nearly 60% of deaths around the world. The extent of this silent epidemic has not met determined responses in governments, policies or professionals in order to transform old Health Care Systems, configured for acute diseases. There is a large list of research about alternative models for people with chronic conditions, many of them with an advanced practice nurse as a key provider, as case management. But some methodological concerns raise, above all, the design of the intervention (intensity, frequency, components, etc). General: To develop the first and second phases (theorization and modeling) for designing a multifaceted case-management intervention in people with chronic conditions (COPD and heart failure) and their caregivers. 1) To identify key events in people living with chronic disease and their relation with the Health Care System, from their point of view. 2) To know the coping mechanisms developed by patients and their caregivers along the story with the disease. 3) To know the information processing and its utilization in their interactions with health care providers. 4) To detect potential unmet needs and the ways deployed by patients and their caregivers to resolve them. 5) To obtain a description from patients and caregivers, about their itineraries along the Health Care System, in terms of continuity, accessibility and comprehensiveness of care. 6) To build up a list of promising case-management interventions in patients with Heart Failure and COPD with this information in order to frame it into theoretical models for its reproducibility and conceptualization. 7) To undergo this list to expert judgment to assess its feasibility and pertinence in the Andalusian Health Care. Qualitative research with two phases: For the first five objectives, a qualitative technique with biographic stories will be developed and, for the remaining objectives, an expert consensus through Delphi technique, on the possible interventions yielded from the first phase. The study will be developed in the provinces of Almería, Málaga and Granada in the Southern Spain, from patients included in the Andalusian Health Care Service database with the diagnosis of COPD or Heart Failure, with the collaboration of case manager nurses and general practitioners for the assessment of their suitability to inclusion criteria. Patients and caregivers will be interviewed in their homes or their Health Centers, with their family or their case manager nurse as mediator. First of a series of studies intended to design a case-management service for people with heart failure and COPD, in the Andalusian Health Care System, where case management has been implemented since 2002. Accordingly with the steps of a theoretical model for complex interventions, in this study, theorization and intervention modeling phases will be developed.

  17. Tutorial for Thermophysics Universal Research Framework

    DTIC Science & Technology

    2017-07-30

    DS1V are compared in Section 3.4.5. 3.4.2 Description of the Example Problem In a fluid, disturbance information is communicated within a medium at the...Universal Research Framework development (TURF-DEV) package on a case-by-case basis. Brief descriptions of the operations are provided in Tables 4.1 and...of additional experimental (E) and research (R) operations included in TURF-DEV. Module Operation Description DSMC SPDistDirectDSMCCellMergeOp (R

  18. Development of a test and flight engineering oriented language. Phase 3: Presentation

    NASA Technical Reports Server (NTRS)

    Kamsler, W. F.; Case, C. W.; Kinney, E. L.; Gyure, J.

    1970-01-01

    The format material used in an oral presentation of the phase 3 study effort is given. The material includes a description of the language ALOFT and a terminology comparison with other test languages.

  19. X-ray phase-contrast imaging: the quantum perspective

    NASA Astrophysics Data System (ADS)

    Slowik, J. M.; Santra, R.

    2013-08-01

    Time-resolved phase-contrast imaging using ultrafast x-ray sources is an emerging method to investigate ultrafast dynamical processes in matter. Schemes to generate attosecond x-ray pulses have been proposed, bringing electronic timescales into reach and emphasizing the demand for a quantum description. In this paper, we present a method to describe propagation-based x-ray phase-contrast imaging in nonrelativistic quantum electrodynamics. We explain why the standard scattering treatment via Fermi’s golden rule cannot be applied. Instead, the quantum electrodynamical treatment of phase-contrast imaging must be based on a different approach. It turns out that it is essential to select a suitable observable. Here, we choose the quantum-mechanical Poynting operator. We determine the expectation value of our observable and demonstrate that the leading order term describes phase-contrast imaging. It recovers the classical expression of phase-contrast imaging. Thus, it makes the instantaneous electron density of non-stationary electronic states accessible to time-resolved imaging. Interestingly, inelastic (Compton) scattering does automatically not contribute in leading order, explaining the success of the semiclassical description.

  20. [Triage duration times: a prospective descriptive study in a level 1° emergency department].

    PubMed

    Bambi, Stefano; Ruggeri, Marco

    2017-01-01

    Triage is the most important tool for clinical risk management in emergency departments (ED). The timing measurement of its phases is fundamental to establish indicators and standards for the optimization of the system. To evaluate the duration time of the phases of triage; to evaluate some variables exerting influence on nurses' performance. prospective descriptive study performed in the ED of Careggi Teaching Hospital in Florence. 14 nurses enrolled by stratified randomization proportion (1/3 of the whole staff ), according to classes of length of service. Triage processes on 150 adult patients were recorded. The mean age of nurses was 39.7 years (SD ± 5.2, range 29-50); the average length of service was 10.3 years (SD ± 4.4, range 3-18); average of triage experience was 8.6 years (SD ± 4.3, range 2-13). The median time from patient's arrival to the end of the triage process was 04': 04" (range 00':47"- 18':08"); the median duration of triage was 01':11" (range 00':07" -11':27"). The length of service and triage experience did not influence the medians of recorded intervals of time, but there were some limitations due to the low sample size. Interruptions were observed 111 (74%) of triage cases. the recorded triage time intervals were similar to those reported in international literature. Actions are needed to reduce the impact of interruptions on triage process' times.

  1. Topological BF field theory description of topological insulators

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

    Cho, Gil Young; Moore, Joel E., E-mail: jemoore@berkeley.edu; Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720

    2011-06-15

    Research Highlights: > We show that a BF theory is the effective theory of 2D and 3D topological insulators. > The non-gauge-invariance of the bulk theory yields surface terms for a bosonized Dirac fermion. > The 'axion' term in electromagnetism is correctly obtained from gapped surfaces. > Generalizations to possible fractional phases are discussed in closing. - Abstract: Topological phases of matter are described universally by topological field theories in the same way that symmetry-breaking phases of matter are described by Landau-Ginzburg field theories. We propose that topological insulators in two and three dimensions are described by a version ofmore » abelian BF theory. For the two-dimensional topological insulator or quantum spin Hall state, this description is essentially equivalent to a pair of Chern-Simons theories, consistent with the realization of this phase as paired integer quantum Hall effect states. The BF description can be motivated from the local excitations produced when a {pi} flux is threaded through this state. For the three-dimensional topological insulator, the BF description is less obvious but quite versatile: it contains a gapless surface Dirac fermion when time-reversal-symmetry is preserved and yields 'axion electrodynamics', i.e., an electromagnetic E . B term, when time-reversal symmetry is broken and the surfaces are gapped. Just as changing the coefficients and charges of 2D Chern-Simons theory allows one to obtain fractional quantum Hall states starting from integer states, BF theory could also describe (at a macroscopic level) fractional 3D topological insulators with fractional statistics of point-like and line-like objects.« less

  2. Phase Relations in Ternary Systems in the Subsolidus Region: Methods to Formulate Solid Solution Equations and to Find Particular Compositions

    ERIC Educational Resources Information Center

    Alvarez-Montan~o, Victor E.; Farías, Mario H.; Brown, Francisco; Mun~oz-Palma, Iliana C.; Cubillas, Fernando; Castillon-Barraza, Felipe F.

    2017-01-01

    A good understanding of ternary phase diagrams is required to advance and/or to reproduce experimental research in solid-state and materials chemistry. The aim of this paper is to describe the solutions to problems that appear when studying or determining ternary phase diagrams. A brief description of the principal features shown in phase diagrams…

  3. [Giant coronary aneurysms in infants with Kawasaki disease].

    PubMed

    Sánchez Andrés, Antonio; Salvador Mercader, Inmaculada; Seller Moya, Julia; Carrasco Moreno, José Ignacio

    2017-08-01

    Kawasaki disease (KD) is an acute vasculitis of unknown origin and predominant in males. The long-term effects of the disease depend on whether there are coronary lesions, particularly aneurysms. The prognosis of patients with giant aneurysms is very poor due to their natural progression to coronary thrombosis or severe obstructive lesions. A series of 8 cases is presented where the epidemiology and diagnostic methods are described. The treatment of the acute and long-term cardiovascular sequelae is also reviewed. A descriptive analysis was conducted on patients admitted to the Paediatric Cardiology Unit of La Fe University Hospital (Valencia) with KD and a coronary lesion. More than one artery was involved in all patients. Although early diagnosis was established in only two cases, none of the patients had severe impairment of ventricular function during the acute phase. Treatment included intravenous gammaglobulin and acetylsalicylic acid at anti-inflammatory doses during the acute phase. A combination of dual antiplatelet therapy and corticosteroids was given in cases of coronary thrombosis. The silent aneurysms continue to persist. KD is the most common cause of acquired heart disease in children. The delay in diagnosis is associated with a greater likelihood of coronary lesions that could increase the risk of cardiovascular events in adulthood. Thus, this subgroup requires close clinical monitoring for a better control of cardiovascular risk factors over time. Copyright © 2016 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Centrosomes are autocatalytic droplets of pericentriolar material organized by centrioles.

    PubMed

    Zwicker, David; Decker, Markus; Jaensch, Steffen; Hyman, Anthony A; Jülicher, Frank

    2014-07-01

    Centrosomes are highly dynamic, spherical organelles without a membrane. Their physical nature and their assembly are not understood. Using the concept of phase separation, we propose a theoretical description of centrosomes as liquid droplets. In our model, centrosome material occurs in a form soluble in the cytosol and a form that tends to undergo phase separation from the cytosol. We show that an autocatalytic chemical transition between these forms accounts for the temporal evolution observed in experiments. Interestingly, the nucleation of centrosomes can be controlled by an enzymatic activity of the centrioles, which are present at the core of all centrosomes. This nonequilibrium feature also allows for multiple stable centrosomes, a situation that is unstable in equilibrium phase separation. Our theory explains the growth dynamics of centrosomes for all cell sizes down to the eight-cell stage of the Caenorhabditis elegans embryo, and it also accounts for data acquired in experiments with aberrant numbers of centrosomes and altered cell volumes. Furthermore, the model can describe unequal centrosome sizes observed in cells with perturbed centrioles. We also propose an interpretation of the molecular details of the involved proteins in the case of C. elegans. Our example suggests a general picture of the organization of membraneless organelles.

  5. Effective transient behaviour of inclusions in diffusion problems

    NASA Astrophysics Data System (ADS)

    Brassart, Laurence; Stainier, Laurent

    2018-06-01

    This paper is concerned with the effective transport properties of heterogeneous media in which there is a high contrast between the phase diffusivities. In this case the transient response of the slow phase induces a memory effect at the macroscopic scale, which needs to be included in a macroscopic continuum description. This paper focuses on the slow phase, which we take as a dispersion of inclusions of arbitrary shape. We revisit the linear diffusion problem in such inclusions in order to identify the structure of the effective (average) inclusion response to a chemical load applied on the inclusion boundary. We identify a chemical creep function (similar to the creep function of viscoelasticity), from which we construct estimates with a reduced number of relaxation modes. The proposed estimates admit an equivalent representation based on a finite number of internal variables. These estimates allow us to predict the average inclusion response under arbitrary time-varying boundary conditions at very low computational cost. A heuristic generalisation to concentration-dependent diffusion coefficient is also presented. The proposed estimates for the effective transient response of an inclusion can serve as a building block for the formulation of multi-inclusion homogenisation schemes.

  6. Bonding structure in amorphous carbon nitride: A spectroscopic and nuclear magnetic resonance study

    NASA Astrophysics Data System (ADS)

    Sánchez-López, J. C.; Donnet, C.; Lefèbvre, F.; Fernández-Ramos, C.; Fernández, A.

    2001-07-01

    Since the prediction of Liu and Cohen [Science 245, 841 (1989)] of the potential extraordinary mechanical properties of crystalline β-C3N4, many authors have attempted its synthesis. However, in most cases, the obtained materials are amorphous phases with a complex bonding structure. Their characterization is complicated due to the absence of a reference compound, the lack of long-range order, and the poor knowledge about their bonding structure. In this article, we present 1H, 13C, and 15N solid-state nuclear magnetic resonance (NMR) measurements for the determination of the bonding types in amorphous CNx films. NMR measurements do not require long-range order and are able to clearly identify the signals from the sp2- and sp3-bonded phases. The analysis of the data obtained by other characterization techniques, such as infrared spectroscopy, x-ray photoelectron spectroscopy, electron energy-loss spectroscopy, and x-ray absorption near-edge spectroscopy on the same sample, based on the information acquired by NMR, enables the description of a structure model for the studied amorphous-CNx phase prepared by dc-magnetron sputtering and to revise the interpretation found in the literature.

  7. Software engineering standards and practices

    NASA Technical Reports Server (NTRS)

    Durachka, R. W.

    1981-01-01

    Guidelines are presented for the preparation of a software development plan. The various phases of a software development project are discussed throughout its life cycle including a general description of the software engineering standards and practices to be followed during each phase.

  8. 30 CFR 250.413 - What must my description of well drilling design criteria address?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... design criteria address? 250.413 Section 250.413 Mineral Resources MINERALS MANAGEMENT SERVICE... drilling design criteria address? Your description of well drilling design criteria must address: (a) Pore... phases, including the anticipated surface pressure used for designing the production string; (g) A single...

  9. 30 CFR 250.413 - What must my description of well drilling design criteria address?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... design criteria address? 250.413 Section 250.413 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL... of well drilling design criteria address? Your description of well drilling design criteria must... the completion phases, including the anticipated surface pressure used for designing the production...

  10. 30 CFR 250.413 - What must my description of well drilling design criteria address?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... design criteria address? 250.413 Section 250.413 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL... of well drilling design criteria address? Your description of well drilling design criteria must... the completion phases, including the anticipated surface pressure used for designing the production...

  11. 30 CFR 250.413 - What must my description of well drilling design criteria address?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... design criteria address? 250.413 Section 250.413 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL... of well drilling design criteria address? Your description of well drilling design criteria must... the completion phases, including the anticipated surface pressure used for designing the production...

  12. 76 FR 4100 - Combined Notice of Filings #1

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-24

    ..., Rolling Thunder I Power Partners, LLC, Goshen Phase II LLC, Cedar Creek II, LLC. Description: Supplemental Information of Rolling Thunder I Power Partners, LLC. Filed Date: 01/12/2011. Accession Number: 20110112-5154...: Rolling Thunder I Power Partners, LLC. Description: Rolling Thunder I Power Partners, LLC submits tariff...

  13. First principles numerical model of avalanche-induced arc discharges in electron-irradiated dielectrics

    NASA Technical Reports Server (NTRS)

    Beers, B. L.; Pine, V. W.; Hwang, H. C.; Bloomberg, H. W.; Lin, D. L.; Schmidt, M. J.; Strickland, D. J.

    1979-01-01

    The model consists of four phases: single electron dynamics, single electron avalanche, negative streamer development, and tree formation. Numerical algorithms and computer code implementations are presented for the first three phases. An approach to developing a code description of fourth phase is discussed. Numerical results are presented for a crude material model of Teflon.

  14. Content Aggregations for Reading Skills and Mathematics for the Comparative Study of Phase IV of the IGE Evaluation Project. Phase IV, Project Paper 80-3.

    ERIC Educational Resources Information Center

    Nerenz, Anne G.; Webb, Norman L.

    This is one of a series of reports which provide definitions of and descriptive data on the variables used in the Comparative Study of Phase IV of the Individually Guided Education (IEG) Evaluation Project. Phase IV investigated three curriculum programs specifically designed to be compatible with instructional programming for the individual…

  15. PHYSICAL EFFECTS OCCURRING DURING GENERATION AND AMPLIFICATION OF LASER RADIATION: Reversal of the contrast of optical radiation in round-trip amplifiers with a phase conjugation mirror

    NASA Astrophysics Data System (ADS)

    Afanas'ev, Anatolii A.; Samson, B. A.

    1989-02-01

    A description is given of a method for inversion of the contrast of optical radiation in a round-trip amplifier with a phase conjugation mirror and a phase nonreciprocal element. The system can be used to achieve high powers of contrast-reversed radiation because of compensation of phase distortions introduced by amplification.

  16. Advanced Traffic Signal Control Algorithms Phase II

    DOT National Transportation Integrated Search

    2015-12-15

    The goal of the project was to design and implement an in-vehicle system that calculates and provide speed advice to the driver of the vehicle, using Signal Phase and Timing (SPaT) and Geometric Information Description (GID) information of the signal...

  17. The Thai Anesthesia Incidents Study (THAI Study) of anesthetic outcomes: I. Description of methods and populations.

    PubMed

    Charuluxananan, Somrat; Suraseranivongse, Suwannee; Punjasawadwong, Yodying; Somboonviboon, Wanna; Nipitsukarn, Thana; Sothikarnmanee, Thepakorn; Vasinanukorn, Mayuree; Werawatganon, Thewarug; Tanudsintum, Surasak; Lekprasert, Varinee; Hintong, Thanoo

    2005-11-01

    Since anesthesia, unlike medical or surgical specialties, does not constitute treatment, The Royal College of Anesthesiologists of Thailand host the Thai Anesthesia Incidents Study (THAI Study) of anesthetic outcomes to determine factors related to anesthesia related adverse events. A prospective descriptive study of occurrence screening was conducted in 20 hospitals comprised of 7 university, 4 general and 4 district hospitals across Thailand. Anesthesia personnels were required to fill up patient-related, surgical-related, anesthesia-related variables and adverse outcomes on a strutured data entry form. The data included preanesthetic evaluation intraoperative period and 24 hr postoperative period. Adverse events specific form was recorded when adverse events occurred. All data were keyed in data management unit with double entry technique and descriptive statistics was used in the first phase of this study. A total of 163403 consecutive cases were recorded in one year. The mean (S.D.) of age, weight and height of patients were 38.6(2.3) yrs, 53.9(17.7) kgs and 153.4(22.7) cm respectively. There were more female (52.9%) than male (47. 1%) patients with ASA PS 1, 2, 3, 4, 5 = 50.8%, 36.3%, 10.7%, 2.0%, 0.2% respectively. Hypertension (11.6%), anemia (7.7%) and diabetes melitus (6.8%) were the three most common abnormalities in preanesthetic history taking. Mallampati score of 111870 patients grade 1, 2, 3, 4 were 54.0%, 39.7%, 5.6%, 0.7% and laryngoscopic grade 1, 2, 3, 4 of 74888 patients were 81.0%, 15.5%, 3.0% and 0.5% respectively. The first phase of THAI study epidemiological project can represent both the anesthesia and surgical profiles in Thailand. The collected data available should be useful for the improvement of the quality of anesthesia, guidelines for clinical practices, medical education and for further research.

  18. Towards driving mantle convection by mineral physics

    NASA Astrophysics Data System (ADS)

    Piazzoni, A. S.; Bunge, H.; Steinle-Neumann, G.

    2005-12-01

    Models of mantle convection have become increasingly sophisticated over the past decade, accounting, for example, for 3 D spherical geometry, and changes in mantle rheology due to variations in temperature and stress. In light of such advances it is surprising that growing constraints on mantle structure derived from mineral physics have not yet been fully brought to bear on mantle convection models. In fact, despite much progress in our understanding of mantle mineralogy a partial description of the equation of state is often used to relate density changes to pressure and temperature alone, without taking into account compositional and mineralogical models of the mantle. Similarly, for phase transitions an incomplete description of thermodynamic constraints is often used, resulting in significant uncertainties in model behavior. While a number of thermodynamic models (some with limited scope) have been constructed recently, some lack the rigor in thermodynamics - for example with respect to the treatment of solid solution - that is needed to make predictions about mantle structure. Here we have constructed a new thermodynamic database for the mantle and have coupled the resulting density dynamically with mantle convection models. The database is build on a self-consistent Gibb's free energy minimization of the system MgO-FeO-SiO2-CaO-Al2O3 that is appropriate for standard (dry) chemical models of the Earth's mantle for relevant high pressure and temperature phases. We have interfaced the database with a high-resolution 2-D convection code (2DTERRA), dynamically coupling the thermodynamic model (density) with the conservation equations of mantle flow. The coupled model is run for different parameterizations of viscosity, initial temperature conditions, and varying the internal vs. external heating. We compare the resulting flow and temperature fields to cases with the Boussinesq approximation and other classical descriptions of the equation of state in mantle dynamics to assess the influence of realistic mineralogical density on mantle convection.

  19. Faculty Perceptions of Teaching Nontraditional College Students: A Qualitative Single Descriptive Case Study

    ERIC Educational Resources Information Center

    Spedding, Lindsey

    2016-01-01

    Nontraditional students bring to the classroom diversity in age, culture, experience, knowledge, and preparedness. The risk factors that circumstantially define nontraditional students outside the classroom result in transferrable challenges within the classroom. The purpose of this single descriptive case study was to explore and understand…

  20. Implementing case study methodology in critical care nursing: a discourse analysis.

    PubMed

    Henning, John E; Nielsen, Lynn E; Hauschildt, James A

    2006-01-01

    The authors provide a description of the classroom interactions as one nursing education professor transformed his teaching from a lecture format to a case study approach. This description serves as a road map for nursing educators who are interested in making the transition to a case study approach by showing how, when, and to what degree they can maximize both student participation and content acquisition.

  1. Linker-mediated assembly of gold nanoparticles into multimeric motifs

    NASA Astrophysics Data System (ADS)

    Sikora, Mateusz; Szymczak, Piotr; Thompson, Damien; Cieplak, Marek

    2011-11-01

    We present a theoretical description of linker-mediated self-assembly of gold nanoparticles (Au-NP). Using mesoscale simulations with a coarse-grained model for the Au NPs and dirhenium-based linker molecules, we investigate the conditions under which large clusters can grow and construct a phase diagram that identifies favorable growth conditions in terms of floating and bound linker concentrations. The findings can be considered as generic, as we expect other NP-linker systems to behave in a qualitatively similar way. In particular, we also discuss the case of antibody-functionalised Au NPs connected by the C-reactive proteins (CRPs). We extract some general rules for NP linking that may aid the production of size- and shape-specific NP clusters for technology applications.

  2. Star-type oscillatory networks with generic Kuramoto-type coupling: A model for "Japanese drums synchrony"

    NASA Astrophysics Data System (ADS)

    Vlasov, Vladimir; Pikovsky, Arkady; Macau, Elbert E. N.

    2015-12-01

    We analyze star-type networks of phase oscillators by virtue of two methods. For identical oscillators we adopt the Watanabe-Strogatz approach, which gives full analytical description of states, rotating with constant frequency. For nonidentical oscillators, such states can be obtained by virtue of the self-consistent approach in a parametric form. In this case stability analysis cannot be performed, however with the help of direct numerical simulations we show which solutions are stable and which not. We consider this system as a model for a drum orchestra, where we assume that the drummers follow the signal of the leader without listening to each other and the coupling parameters are determined by a geometrical organization of the orchestra.

  3. A complete analytical solution of the Fokker-Planck and balance equations for nucleation and growth of crystals

    NASA Astrophysics Data System (ADS)

    Makoveeva, Eugenya V.; Alexandrov, Dmitri V.

    2018-01-01

    This article is concerned with a new analytical description of nucleation and growth of crystals in a metastable mushy layer (supercooled liquid or supersaturated solution) at the intermediate stage of phase transition. The model under consideration consisting of the non-stationary integro-differential system of governing equations for the distribution function and metastability level is analytically solved by means of the saddle-point technique for the Laplace-type integral in the case of arbitrary nucleation kinetics and time-dependent heat or mass sources in the balance equation. We demonstrate that the time-dependent distribution function approaches the stationary profile in course of time. This article is part of the theme issue `From atomistic interfaces to dendritic patterns'.

  4. Ising versus XY anisotropy in frustrated R(2)Ti(2)O(7) compounds as "Seen" by Polarized Neutrons.

    PubMed

    Cao, H; Gukasov, A; Mirebeau, I; Bonville, P; Decorse, C; Dhalenne, G

    2009-07-31

    We studied the field induced magnetic order in R(2)Ti(2)O(7) pyrochlore compounds with either uniaxial (R=Ho, Tb) or planar (R=Er, Yb) anisotropy, by polarized neutron diffraction. The determination of the local susceptibility tensor {chi(parallel to),chi(perpendicular)} provides a universal description of the field induced structures in the paramagnetic phase (2-270 K), whatever the field value (1-7 T) and direction. Comparison of the thermal variations of chi(parallel to) and chi(perpendicular) with calculations using the rare earth crystal field shows that exchange and dipolar interactions must be taken into account. We determine the molecular field tensor in each case and show that it can be strongly anisotropic.

  5. Creating Entrustable Professional Activities to Assess Internal Medicine Residents in Training: A Mixed-Methods Approach.

    PubMed

    Taylor, David R; Park, Yoon Soo; Smith, Christopher A; Karpinski, Jolanta; Coke, William; Tekian, Ara

    2018-05-15

    Competency-based medical education has not advanced residency training as much as many observers expected. Some medical educators now advocate reorienting competency-based approaches to focus on a resident's ability to do authentic clinical work. To develop descriptions of clinical work for which internal medicine residents must gain proficiency to deliver meaningful patient care (for example, "Admit and manage a medical inpatient with a new acute problem"). A modified Delphi process involving clinical experts followed by a conference of educational experts. The Royal College of Physicians and Surgeons of Canada. In phase 1 of the project, members of the Specialty Committee for Internal Medicine participated in a modified Delphi process to identify activities in internal medicine that represent the scope of the specialty. In phase 2 of the project, 5 experts who were scholars and leaders in competency-based medical education reviewed the results. Phase 1 identified important activities, revised descriptions to improve accuracy and avoid overlap, and assigned activities to stages of training. Phase 2 compared proposed activity descriptions with published guidelines for their development and application in medical education. The project identified 29 activities that qualify as entrustable professional activities. The project also produced a detailed description of each activity and guidelines for using them to assess residents. These activities reflect the practice patterns of the developers and may not fully represent internal medicine practice in Canada. Identification of these activities is expected to facilitate modification of training and assessment programs for medical residents so that programs focus less on isolated skills and more on integrated tasks. Southeastern Ontario Academic Medical Organization Endowed Scholarship and Education Fund and Queen's University Department of Medicine Innovation Fund.

  6. Assessing ConnDOT's portland cement concrete testing methods phase II : field trials and implementation.

    DOT National Transportation Integrated Search

    2012-04-01

    This paper presents a description of efforts to disseminate findings from the Phase I study (SPR-2244), provides examples of applied maturity testing and temperature monitoring in Connecticut, reviews several State Highway Agency protocols for using ...

  7. Analytic Description of Critical Point Nuclei in a Spherical-Axially Deformed Shape Phase Transition

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

    Iachello, F.

    2001-07-30

    An approximate solution at the critical point of the spherical to axially deformed shape phase transition in nuclei is presented. The eigenvalues of the Hamiltonian are expressed in terms of zeros of Bessel functions of irrational order.

  8. Software Engineering Laboratory (SEL) programmer workbench phase 1 evaluation

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Phase 1 of the SEL programmer workbench consists of the design of the following three components: communications link, command language processor, and collection of software aids. A brief description, and evaluation, and recommendations are presented for each of these three components.

  9. 78 FR 27372 - Combined Notice of Filings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-10

    ... Number: 20130501-5062. Comments Due: 5 p.m. ET 5/13/13. Docket Numbers: RP13-863-000. Applicants: Big...: Transcontinental Gas Pipe Line Company. Description: Mid-South Expansion Project Phase 2 Rates to be effective 6/1... Numbers: RP13-872-000. Applicants: TC Offshore LLC. Description: Cashout Surcharge 2013 to be effective 6...

  10. 78 FR 76383 - Notice of Passenger Facility Charge (PFC) Approvals and Disapprovals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-17

    ...: LGA runways 4 and 31 runway safety area planning, environmental, and engineering. Brief Description of... Collection at EWR and Use at JFK at a $3.00 PFC Level: JFK taxiway P rehabilitation planning and engineering... delay reduction phase II--planning and engineering. Brief Description of Project Approved for Collection...

  11. Generalization of the Bogoliubov-Zubarev Theorem for Dynamic Pressure to the Case of Compressibility

    NASA Astrophysics Data System (ADS)

    Rudoi, Yu. G.

    2018-01-01

    We present the motivation, formulation, and modified proof of the Bogoliubov-Zubarev theorem connecting the pressure of a dynamical object with its energy within the framework of a classical description and obtain a generalization of this theorem to the case of dynamical compressibility. In both cases, we introduce the volume of the object into consideration using a singular addition to the Hamiltonian function of the physical object, which allows using the concept of the Bogoliubov quasiaverage explicitly already on a dynamical level of description. We also discuss the relation to the same result known as the Hellmann-Feynman theorem in the framework of the quantum description of a physical object.

  12. Discovery of a metastable Al20Sm4 phase

    NASA Astrophysics Data System (ADS)

    Ye, Z.; Zhang, F.; Sun, Y.; Mendelev, M. I.; Ott, R. T.; Park, E.; Besser, M. F.; Kramer, M. J.; Ding, Z.; Wang, C.-Z.; Ho, K.-M.

    2015-03-01

    We present an efficient genetic algorithm, integrated with experimental diffraction data, to solve a nanoscale metastable Al20Sm4 phase that evolves during crystallization of an amorphous magnetron sputtered Al90Sm10 alloy. The excellent match between calculated and experimental X-ray diffraction patterns confirms an accurate description of this metastable phase. Molecular dynamic simulations of crystal growth from the liquid phase predict the formation of disordered defects in the devitrified crystal.

  13. Analytical description of the ternary melt and solution crystallization with a non-linear phase diagram

    NASA Astrophysics Data System (ADS)

    Toropova, L. V.; Alexandrov, D. V.

    2018-05-01

    The directional solidification of a ternary system with an extended phase transition region is theoretically studied. A mathematical model is developed to describe quasi-stationary solidification, and its analytical solution is constructed with allowance for a nonlinear liquids line equation. We demonstrate that the phase diagram nonlinearity leads to substantial changes of analytical solutions.

  14. Functional description of signal processing in the Rogue GPS receiver

    NASA Technical Reports Server (NTRS)

    Thomas, J. B.

    1988-01-01

    Over the past year, two Rogue GPS prototype receivers have been assembled and successfully subjected to a variety of laboratory and field tests. A functional description is presented of signal processing in the Rogue receiver, tracing the signal from RF input to the output values of group delay, phase, and data bits. The receiver can track up to eight satellites, without time multiplexing among satellites or channels, simultaneously measuring both group delay and phase for each of three channels (L1-C/A, L1-P, L2-P). The Rogue signal processing described requires generation of the code for all three channels. Receiver functional design, which emphasized accuracy, reliability, flexibility, and dynamic capability, is summarized. A detailed functional description of signal processing is presented, including C/A-channel and P-channel processing, carrier-aided averaging of group delays, checks for cycle slips, acquistion, and distinctive features.

  15. Inheritance on processes, exemplified on distributed termination detection

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

    Thomsen, K.S.

    1987-02-01

    A multiple inheritance mechanism on processes is designed and presented within the framework of a small object oriented language. Processes are described in classes, and the different action parts of a process inherited from different classes are executed in a coroutine-like style called alternation. The inheritance mechanism is a useful tool for factorizing the description of common aspects of processes. This is demonstrated within the domain of distributed programming by using the inheritance mechanism to factorize the description of distributed termination detection algorithms from the description of the distributed main computations for which termination is to be detected. A clearmore » separation of concerns is obtained, and arbitrary combinations of terminations detection algorithms and main computations can be formed. The same termination detection classes can also be used for more general purposes within distributed programming, such as detecting termination of each phase in a multi-phase main computation.« less

  16. Sweeping as a multistep enrichment process in micellar electrokinetic chromatography: the retention factor gradient effect.

    PubMed

    El-Awady, Mohamed; Pyell, Ute

    2013-07-05

    The application of a new method developed for the assessment of sweeping efficiency in MEKC under homogeneous and inhomogeneous electric field conditions is extended to the general case, in which the distribution coefficient and the electric conductivity of the analyte in the sample zone and in the separation compartment are varied. As test analytes p-hydroxybenzoates (parabens), benzamide and some aromatic amines are studied under MEKC conditions with SDS as anionic surfactant. We show that in the general case - in contrast to the classical description - the obtainable enrichment factor is not only dependent on the retention factor of the analyte in the sample zone but also dependent on the retention factor in the background electrolyte (BGE). It is shown that in the general case sweeping is inherently a multistep focusing process. We describe an additional focusing/defocusing step (the retention factor gradient effect, RFGE) quantitatively by extending the classical equation employed for the description of the sweeping process with an additional focusing/defocusing factor. The validity of this equation is demonstrated experimentally (and theoretically) under variation of the organic solvent content (in the sample and/or the BGE), the type of organic solvent (in the sample and/or the BGE), the electric conductivity (in the sample), the pH (in the sample), and the concentration of surfactant (in the BGE). It is shown that very high enrichment factors can be obtained, if the pH in the sample zone makes possible to convert the analyte into a charged species that has a high distribution coefficient with respect to an oppositely charged micellar phase, while the pH in the BGE enables separation of the neutral species under moderate retention factor conditions. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Study of Thermodynamics of Liquid Noble-Metals Alloys Through a Pseudopotential Theory

    NASA Astrophysics Data System (ADS)

    Vora, Aditya M.

    2010-09-01

    The Gibbs-Bogoliubov (GB) inequality is applied to investigate the thermodynamic properties of some equiatomic noble metal alloys in liquid phase such as Au-Cu, Ag-Cu, and Ag-Au using well recognized pseudopotential formalism. For description of the structure, well known Percus-Yevick (PY) hard sphere model is used as a reference system. By applying a variation method the best hard core diameters have been found which correspond to minimum free energy. With this procedure the thermodynamic properties such as entropy and heat of mixing have been computed. The influence of local field correction function viz; Hartree (H), Taylor (T), Ichimaru-Utsumi (IU), Farid et al. (F), and Sarkar et al. (S) is also investigated. The computed results of the excess entropy compares favourably in the case of liquid alloys while the agreement with experiment is poor in the case of heats of mixing. This may be due to the sensitivity of the heats of mixing with the potential parameters and the dielectric function.

  18. A COMBINED TREATMENT APPROACH EMPHASIZING IMPAIRMENT-BASED MANUAL THERAPY AND EXERCISE FOR HIP-RELATED COMPENSATORY INJURY IN ELITE ATHLETES: A CASE SERIES

    PubMed Central

    Short, Gretchen; Strack, Donald; Anloague, Philip; Brewster, Brian

    2017-01-01

    Background/Purpose: Athletes experiencing hip, groin, and low back pain often exhibit similar clinical characteristics. Individuals with hip, groin and low back pain may have the presence of multiple concurrent pathoanatomical diagnoses. Regardless, similar regional characteristics and dysfunction may contribute to the patient's chief complaint, potentially creating a sub-group of individuals that may be defined by lumbopelvic and hip mobility limitations, motor control impairments, and other shared clinical findings. The purpose of this case series is to describe the conservative management of elite athletes, within the identified aforementioned sub-group, that emphasized regional manual therapy interventions, and therapeutic exercise designed to improve lumbopelvic and hip mobility, stability and motor control. Case Descriptions: Five elite athletes were clinically diagnosed by a physical therapist with primary pathologies including adductor-related groin pain (ARGP), femoral acetabular impingement (FAI) with acetabular labral lesion and acute, mechanical low back pain (LBP). Similar subjective, objective findings and overall clinical profiles were identified among all subjects. Common findings aside from the chief complaint included, but were not limited to, decreased hip range of motion (ROM), impaired lumbopelvic motor control and strength, lumbar hypomobility in at least one segment, and a positive hip flexion-adduction-internal rotation (FADIR) special test. A three-phase impairment-based physical therapy program was implemented to resolve the primary complaints and return the subjects to their desired level of function. Acute phase rehabilitation consisted of manual therapy and fundamental motor control exercises. Progression to the sub-acute and terminal phases was based on improved subjective pain reports and progress with functional impairments. As the subjects progress through the rehabilitation phases, the delivery of physical therapy interventions were defined by decreased manual therapies and an increased emphasis and priority on graded exercise. Outcomes: Significant reductions in reported pain (>2 points Numeric Pain Rating Scale), improved reported function via functional outcome measures (Hip and Groin Outcome Score), and continued participation in sport occurred in all five cases without the need for surgical intervention. Discussion: The athletes described in this case series make up a common clinical sub-group defined by hip and lumbopelvic mobility restrictions, lumbopelvic and lower extremity motor control impairments and potentially other shared clinical findings. Despite differences in pathoanatomic findings, similar objective findings were identified and similar treatment plans were applied, potentially affecting the movement system as a whole. Subjects were conservatively managed allowing continued participation in sport within their competitive seasons. Conclusion: Comprehensive conservative treatment of the athletes with shared impairments, as described in this case series, may be of clinical importance when managing athletes with hip, groin, and low back pain. Level of Evidence: Therapy, Level 4, Case Series PMID:29158960

  19. Exploring the Causes of Underachievement of African American Boys: A Qualitative Descriptive Case Study

    ERIC Educational Resources Information Center

    Ennis, Rosetta

    2017-01-01

    The qualitative descriptive case study explores the underachievement phenomenon of fourth-grade African American boys in New York City public elementary schools. Numerous studies have been conducted at the middle school through college levels. However, very little is known about the underachievement phenomenon of fourth-grade African American…

  20. Yergason's Test: Discrepancies in Description and Implications for Diagnosing Biceps Subluxation

    ERIC Educational Resources Information Center

    Pettitt, Robert W.; Sailor, Scott R.; Lentell, Gary; Tanner, Cary; Murray, Steven R.

    2008-01-01

    Yergason described the case of a woman with bicipital pain that was confirmed with isolated forearm supination. Since publication of this respective case report in 1931, orthopedic assessment textbooks have provided a wide range of descriptions for Yergason's Test and what a positive sign implicates. Vast differences in hand placement, along with…

  1. The Characteristics of a Community of Practice in a National Writing Project Invitational Summer Institute

    ERIC Educational Resources Information Center

    Pearce, Terisa Ronette

    2010-01-01

    This qualitative naturalistic descriptive case study provides an understanding of the characteristics of a community of practice within a National Writing Project invitational summer institute. This study utilized naturalistic, descriptive case study methodology to answer the research question: What characteristics of a community of practice are…

  2. Impact of Single-Case Pupil Descriptions on Student Teacher Attitudes towards Inclusive Education

    ERIC Educational Resources Information Center

    Röhm, Alexander; Schnöring, Annika; Hastall, Matthias R.

    2018-01-01

    Institutional and individual stigmatization are still major barriers for children with disabilities to access education. Teacher attitudes towards inclusive education play a crucial role in this regard, and are shaped by single-case descriptions from mass media or other sources. Building on exemplification theory and priming, two experiments with…

  3. World Perspective Case Descriptions on Educational Programs for Adults: Portugal.

    ERIC Educational Resources Information Center

    Soares de Melo, Alvaro; Cristovao, Artur F. A. C.

    The case descriptions of two adult education programs in Portual contained in this document are part of a set that reflects a cooperative effort by adult educators to increase international understanding of various educational programs for adults in their societal context. A face sheet for each program provides this information: name,…

  4. Baseline Description and Analysis of the Operations Related to Warehouse Controlled Documents at the Navy Publications and Forms Center, Philadelphia, Pennsylvania. Volume I. Phase I.

    DTIC Science & Technology

    1980-03-06

    performing the present NPFC tasks. Potential automation technologies may include order processing mechanization, demand printing from micrographic or...effort and documented in this volume included the following: a. Functional description of the order processing activities as they currently operate. b...covered under each analysis area. i It is obvious from the exhibit that the functional description of order processing operations was to include COG I

  5. The 30/20 GHz flight experiment system, phase 2. Volume 2: Experiment system description

    NASA Technical Reports Server (NTRS)

    Bronstein, L.; Kawamoto, Y.; Ribarich, J. J.; Scope, J. R.; Forman, B. J.; Bergman, S. G.; Reisenfeld, S.

    1981-01-01

    A detailed technical description of the 30/20 GHz flight experiment system is presented. The overall communication system is described with performance analyses, communication operations, and experiment plans. Hardware descriptions of the payload are given with the tradeoff studies that led to the final design. The spacecraft bus which carries the payload is discussed and its interface with the launch vehicle system is described. Finally, the hardwares and the operations of the terrestrial segment are presented.

  6. 77 FR 19660 - Combined Notice of Filings #1

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-02

    .... Applicants: Goshen Phase II LLC, Ridgeline Alternative Energy, LLC. Description: Joint Application for Authorization under Section 203 of the Federal Power Act of Goshen Phase II and Ridgeline Alternative Energy... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 1 Take notice...

  7. 7 CFR 3403.4 - Three-phase program.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., AND EXTENSION SERVICE, DEPARTMENT OF AGRICULTURE SMALL BUSINESS INNOVATION RESEARCH GRANTS PROGRAM Program Description § 3403.4 Three-phase program. The Small Business Innovation Research Grants Program is... technical merit and feasibility of the proposed effort and the quality of performance of the small business...

  8. Qualitative task analysis to enhance sports characterization: a surfing case study.

    PubMed

    Moreira, Miguel; Peixoto, César

    2014-09-29

    The aim of this study was to develop a Matrix of Analysis for Sports Tasks (MAST), regardless of the sports activity, based on practice classification and task analysis. Being this a qualitative research our main question was: in assessing sports' structure is it possible to make the characterization of any discipline through context and individuals' behaviours? The sample was within a surf discipline in a competition flowing having 5 of the top 16 Portuguese surfers training together. Based on a qualitative method, studying the surf as the main activity was an interpretative study case. The MAST was applied in four phases: taxonomy; tasks and context description; task analysis; teaching and performance strategies. Its application allowed the activities' characterization through the observation, surfer's opinions and bibliographical support. The triangulation of the data was used as an information data treatment. The elements were classified by the challenges proposed to the practitioners and the taxonomy was constituted by the sport activities, group, modality and discipline. Surf is a discipline of surfing which is a sliding sport modality, therefore, a nature sport. In the context description, we had the wave's components and constraints and the surfboards' qualities. Through task analysis we obtained a taxonomy of surf manoeuvres. The structural and functional analysis allowed finding solutions for learning of surf techniques with trampoline and skateboards because these fit in sliding sports. MAST makes possible the development of strategies that benefit teaching and performance intervention.

  9. Qualitative Task Analysis to Enhance Sports Characterization: A Surfing Case Study

    PubMed Central

    Moreira, Miguel; Peixoto, César

    2014-01-01

    The aim of this study was to develop a Matrix of Analysis for Sports Tasks (MAST), regardless of the sports activity, based on practice classification and task analysis. Being this a qualitative research our main question was: in assessing sports’ structure is it possible to make the characterization of any discipline through context and individuals’ behaviours? The sample was within a surf discipline in a competition flowing having 5 of the top 16 Portuguese surfers training together. Based on a qualitative method, studying the surf as the main activity was an interpretative study case. The MAST was applied in four phases: taxonomy; tasks and context description; task analysis; teaching and performance strategies. Its application allowed the activities’ characterization through the observation, surfer’s opinions and bibliographical support. The triangulation of the data was used as an information data treatment. The elements were classified by the challenges proposed to the practitioners and the taxonomy was constituted by the sport activities, group, modality and discipline. Surf is a discipline of surfing which is a sliding sport modality, therefore, a nature sport. In the context description, we had the wave’s components and constraints and the surfboards’ qualities. Through task analysis we obtained a taxonomy of surf manoeuvres. The structural and functional analysis allowed finding solutions for learning of surf techniques with trampoline and skateboards because these fit in sliding sports. MAST makes possible the development of strategies that benefit teaching and performance intervention. PMID:25414757

  10. Identifying Inconsistencies and Reporting Deficits in Therapeutic Massage and Bodywork (TMB) Case Reports Authored by TMB Practitioners: a TMB-Adapted CAse REport (CARE) Guidelines Audit Through 2014.

    PubMed

    Munk, Niki; Shue, Sarah; Freeland, Emilee; Ralston, Rick; Boulanger, Karen T

    2016-09-01

    Case reports are a fundamental tool through which therapeutic massage and bodywork (TMB) practitioners can inform research and impact their field by detailing the presentation, treatment, and follow-up of a single individual encountered in practice. Inconsistencies in case reporting limit their impact as fundamental sources of clinical evidence. Using the TMB-adapted CAse REport (CARE) guidelines, the current study sought to provide a rich description regarding the reporting quality of TMB practitioner authored TMB case reports in the literature. 1) Systematic identification of published, peer-reviewed TMB case reports authored by TMB practitioners following PRISMA recommendations; 2) audit development based on TMB-adapted CARE guidelines; 3) audit implementation; and 4) descriptive analysis of audit scores. Our search identified 977 articles and 35 met study inclusion criteria. On average, TMB case reports included approximately 58% of the total items identified as necessary by the TMB-adapted CARE guidelines. Introduction sections of case reports had the best item reporting (80% on average), while Case Presentation (54%) and Results (52%) sections scored moderately overall, with only 20% of necessary Practitioner Description items included on average. Audit scores revealed inconsistent abstract reporting and few audited case reports including client race (20%), perspective (26%), and occupation/activities (40%); practitioner practice setting (12%), training (12%), scope-of-practice (29%), and credentialing (20%); adverse events or lack thereof (17%); and some aspect of informed consent (34%). Treatment descriptor item reporting varied from high to low. Various implications of concern are discussed. The current audit and descriptive analysis highlight several reporting inconsistencies in TMB case reports prior to 2015. Reporting guidelines for case reports are important if standards for, and impact of, TMB case reports are desired. Adherence to reporting specifications outlined by the TMB-adapted CARE guidelines could improve the impact and usability of TMB case reports in research, education, and practice.

  11. Identifying Inconsistencies and Reporting Deficits in Therapeutic Massage and Bodywork (TMB) Case Reports Authored by TMB Practitioners: a TMB-Adapted CAse REport (CARE) Guidelines Audit Through 2014†

    PubMed Central

    Munk, Niki; Shue, Sarah; Freeland, Emilee; Ralston, Rick; Boulanger, Karen T.

    2016-01-01

    Introduction Case reports are a fundamental tool through which therapeutic massage and bodywork (TMB) practitioners can inform research and impact their field by detailing the presentation, treatment, and follow-up of a single individual encountered in practice. Inconsistencies in case reporting limit their impact as fundamental sources of clinical evidence. Using the TMB-adapted CAse REport (CARE) guidelines, the current study sought to provide a rich description regarding the reporting quality of TMB practitioner authored TMB case reports in the literature. Methods 1) Systematic identification of published, peer-reviewed TMB case reports authored by TMB practitioners following PRISMA recommendations; 2) audit development based on TMB-adapted CARE guidelines; 3) audit implementation; and 4) descriptive analysis of audit scores. Results Our search identified 977 articles and 35 met study inclusion criteria. On average, TMB case reports included approximately 58% of the total items identified as necessary by the TMB-adapted CARE guidelines. Introduction sections of case reports had the best item reporting (80% on average), while Case Presentation (54%) and Results (52%) sections scored moderately overall, with only 20% of necessary Practitioner Description items included on average. Audit scores revealed inconsistent abstract reporting and few audited case reports including client race (20%), perspective (26%), and occupation/activities (40%); practitioner practice setting (12%), training (12%), scope-of-practice (29%), and credentialing (20%); adverse events or lack thereof (17%); and some aspect of informed consent (34%). Treatment descriptor item reporting varied from high to low. Various implications of concern are discussed. Conclusion The current audit and descriptive analysis highlight several reporting inconsistencies in TMB case reports prior to 2015. Reporting guidelines for case reports are important if standards for, and impact of, TMB case reports are desired. Adherence to reporting specifications outlined by the TMB-adapted CARE guidelines could improve the impact and usability of TMB case reports in research, education, and practice. PMID:27648108

  12. Systematic and Automated Development of Quantum Mechanically Derived Force Fields: The Challenging Case of Halogenated Hydrocarbons.

    PubMed

    Prampolini, Giacomo; Campetella, Marco; De Mitri, Nicola; Livotto, Paolo Roberto; Cacelli, Ivo

    2016-11-08

    A robust and automated protocol for the derivation of sound force field parameters, suitable for condensed-phase classical simulations, is here tested and validated on several halogenated hydrocarbons, a class of compounds for which standard force fields have often been reported to deliver rather inaccurate performances. The major strength of the proposed protocol is that all of the parameters are derived only from first principles because all of the information required is retrieved from quantum mechanical data, purposely computed for the investigated molecule. This a priori parametrization is carried out separately for the intra- and intermolecular contributions to the force fields, respectively exploiting the Joyce and Picky programs, previously developed in our group. To avoid high computational costs, all quantum mechanical calculations were performed exploiting the density functional theory. Because the choice of the functional is known to be crucial for the description of the intermolecular interactions, a specific procedure is proposed, which allows for a reliable benchmark of different functionals against higher-level data. The intramolecular and intermolecular contribution are eventually joined together, and the resulting quantum mechanically derived force field is thereafter employed in lengthy molecular dynamics simulations to compute several thermodynamic properties that characterize the resulting bulk phase. The accuracy of the proposed parametrization protocol is finally validated by comparing the computed macroscopic observables with the available experimental counterparts. It is found that, on average, the proposed approach is capable of yielding a consistent description of the investigated set, often outperforming the literature standard force fields, or at least delivering results of similar accuracy.

  13. The Zond Victory Garden Phase 4 windfarm: A planning, installation, and performance case study. Final report

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

    Chapman, J.

    1994-07-01

    This is one of a series of reports that document the steps taken to plan and install a utility-scale windfarm and follow its energy production performance. The reports are intended to help utility planners and others better understand the issues involved in installing and operating a windfarm. This report describes the Zond Victory Garden Phase IV (VGIV) windfarm in the Tehachapi mountain region, 100 miles north of Los Angeles. The Victory Garden series of windfarms were planned and installed and are operated by Zond Systems, Inc. of Tehachapi, California. The VGIV installation, which became operational in stages from January throughmore » June 1990, consists of 98 Vestas V27--225 wind turbines. The total rated capacity is 22 MW with a projected annual average net energy production of 54.3 million kWh/yr, equivalent to an annual capacity factor of 0.28. This energy projection, based on extensive wind resource measurements and an average wind turbine availability of 97%, includes the effects of a number of operational loss factors. The report includes descriptions of the windfarm layout, the wind turbine component, and the electrical layout. Particular attention is paid to one of the most important issues in implementing a windfarm, namely, the wind resource assessment and its use in projecting and updating the expected annual-average energy production of the facility. Also included are details of the planning, construction, and commissioning of the windfarm along with a description of the operations and maintenance procedures employed.« less

  14. Inferring processes of cultural transmission: the critical role of rare variants in distinguishing neutrality from novelty biases.

    PubMed

    O'Dwyer, James P; Kandler, Anne

    2017-12-05

    Neutral evolution assumes that there are no selective forces distinguishing different variants in a population. Despite this striking assumption, many recent studies have sought to assess whether neutrality can provide a good description of different episodes of cultural change. One approach has been to test whether neutral predictions are consistent with observed progeny distributions, recording the number of variants that have produced a given number of new instances within a specified time interval: a classic example is the distribution of baby names. Using an overlapping generations model, we show that these distributions consist of two phases: a power-law phase with a constant exponent of [Formula: see text], followed by an exponential cut-off for variants with very large numbers of progeny. Maximum-likelihood estimations of the model parameters provide a direct way to establish whether observed empirical patterns are consistent with neutral evolution. We apply our approach to a complete dataset of baby names from Australia. Crucially, we show that analyses based on only the most popular variants, as is often the case in studies of cultural evolution, can provide misleading evidence for underlying transmission hypotheses. While neutrality provides a plausible description of progeny distributions of abundant variants, rare variants deviate from neutrality. Further, we develop a simulation framework that allows the detection of alternative cultural transmission processes. We show that anti-novelty bias is able to replicate the complete progeny distribution of the Australian dataset.This article is part of the themed issue 'Process and pattern in innovations from cells to societies'. © 2017 The Author(s).

  15. Supportive Training for Inexperienced and New Teachers (STINT). Part I.

    ERIC Educational Resources Information Center

    Fox, David J.; And Others

    This document is an evaluative description of the program conducted by the New York City Board of Education during the 1968-69 school year. Opening chapters describe the two-phase evaluation design (descriptive and qualitative) and outline the program in which an initial group of 152 master teachers plus 100 more added in Febraury were assigned as…

  16. Solar power satellite system definition study, phase 2. Volume 2: Reference system description

    NASA Technical Reports Server (NTRS)

    1979-01-01

    System descriptions and cost estimates for the reference system of the solar power satellite program are presented. The reference system is divided into five principal elements: the solar power satellites; space construction and support; space and ground transportation; ground receiving stations; and operations control. The program scenario and non-recurring costs are briefly described.

  17. Hermes phasing GNC functions

    NASA Astrophysics Data System (ADS)

    Legenne, J.; Broca, R.; Alby, F.

    1992-08-01

    A review is presented of the French Guidance, Navigation and Control Simulator (GNC) developed to analyze and validate the global phasing strategy of the Hermes spaceplane. The phasing strategy, the events management, and the requirements for simulation are described, and a functional description of the simulator is given. The simulator will be able to assess the performance of the strategy in terms of fuel consumption and duration (mean values, standard deviations).

  18. NASA Physical Sciences - Presentation to Annual Two Phase Heat Transfer International Topical Team Meeting

    NASA Technical Reports Server (NTRS)

    Chiaramonte, Francis; Motil, Brian; McQuillen, John

    2014-01-01

    The Two-phase Heat Transfer International Topical Team consists of researchers and members from various space agencies including ESA, JAXA, CSA, and RSA. This presentation included descriptions various fluid experiments either being conducted by or planned by NASA for the International Space Station in the areas of two-phase flow, flow boiling, capillary flow, and crygenic fluid storage.

  19. Pressure-induced orientational glass phase in molecular para-hydrogen.

    PubMed

    Schelkacheva, T I; Tareyeva, E E; Chtchelkatchev, N M

    2009-02-01

    We propose a theoretical description of a possible orientational glass transition in solid molecular para-hydrogen and ortho-deuterium under pressure supposing that they are mixtures of J=0 and J=2 states of molecules. The theory uses the basic concepts and methods of standard spin-glass theory. We expect our orientational glass to correspond to the II' phase of the high-pressure hydrogen phase diagram.

  20. Secondary School Senior Capstone Projects: A Descriptive and Interpretive Case Study on Post-Secondary Students' Perspectives of Learning Transfer

    ERIC Educational Resources Information Center

    Yasuda, Vanessa Applbaum

    2017-01-01

    This descriptive and interpretive case study investigates how 12 undergraduate college students perceived participation in their high school Senior Capstone Project (SCP) impacted their college academic experience. Learning transfer was explored from the learner's perspective. Data was collected using qualitative methods in three sequential phases…

  1. Art Therapy for an Individual with Late Stage Dementia: A Clinical Case Description

    ERIC Educational Resources Information Center

    Tucknott-Cohen, Tisah; Ehresman, Crystal

    2016-01-01

    This article describes the healing benefits of art therapy for an individual with dementia of the Alzheimer's type. In this clinical case description, a woman diagnosed with Alzheimer's disease received individual art therapy for 17 weeks. The treatment concerns that arose, altered view of reality, agitation, and retrogenesis provide insight on…

  2. The Efficacy of Multicultural Education Training in Teacher-Credentialing Programs: A Descriptive Case Study

    ERIC Educational Resources Information Center

    Delk, Tricia

    2017-01-01

    The purpose of the qualitative descriptive embedded single case study research was to explore how multicultural curriculum and instruction in a teacher-credentialing program prepared pre-service teachers to work with diverse students. The problem was the inadequacy on the part of teacher-credentialing programs to train pre-service teachers to make…

  3. Classroom Management for Kids Who Won't Sit Still and Other "Bad Apples"

    ERIC Educational Resources Information Center

    Cahill, Susan M.

    2006-01-01

    This article presents a case description of collaboration between an occupational therapist and a general education teacher to develop an effective classroom management system. The classroom management system described here was based on the Alert Program for Self-regulation: How Does Your Engine Run? In addition, the case description provides a…

  4. Teacher Perceptions and Use of the Internet in the Classroom: A Descriptive Case Study

    ERIC Educational Resources Information Center

    Garcia, Steven Michael

    2010-01-01

    The purpose of this descriptive qualitative case study was to explore teacher perceptions and use of the Internet as a tool for constructivist learning. Based on a review of the literature, some researchers concluded that the Internet may be a catalyst for an instructional paradigm towards constructivism (Collins, 1991; Sheingold, 1991; Hadley &…

  5. Innovative Methods for Collecting and Analyzing Qualitative Data: Vignettes and Pre-Structured Cases.

    ERIC Educational Resources Information Center

    Miles, Matthew B.

    Two innovative methods for collecting and analyzing qualitative data are vignettes and pre-structured cases. Vignettes are descriptions of situations or problems written by a professional, with a suggested outline and comments provided by a researcher. Advantages of this method are strength of impact of the written descriptions and efficiency of…

  6. Adapting Rational Unified Process (RUP) approach in designing a secure e-Tendering model

    NASA Astrophysics Data System (ADS)

    Mohd, Haslina; Robie, Muhammad Afdhal Muhammad; Baharom, Fauziah; Darus, Norida Muhd; Saip, Mohamed Ali; Yasin, Azman

    2016-08-01

    e-Tendering is an electronic processing of the tender document via internet and allow tenderer to publish, communicate, access, receive and submit all tender related information and documentation via internet. This study aims to design the e-Tendering system using Rational Unified Process approach. RUP provides a disciplined approach on how to assign tasks and responsibilities within the software development process. RUP has four phases that can assist researchers to adjust the requirements of various projects with different scope, problem and the size of projects. RUP is characterized as a use case driven, architecture centered, iterative and incremental process model. However the scope of this study only focusing on Inception and Elaboration phases as step to develop the model and perform only three of nine workflows (business modeling, requirements, analysis and design). RUP has a strong focus on documents and the activities in the inception and elaboration phases mainly concern the creation of diagrams and writing of textual descriptions. The UML notation and the software program, Star UML are used to support the design of e-Tendering. The e-Tendering design based on the RUP approach can contribute to e-Tendering developers and researchers in e-Tendering domain. In addition, this study also shows that the RUP is one of the best system development methodology that can be used as one of the research methodology in Software Engineering domain related to secured design of any observed application. This methodology has been tested in various studies in certain domains, such as in Simulation-based Decision Support, Security Requirement Engineering, Business Modeling and Secure System Requirement, and so forth. As a conclusion, these studies showed that the RUP one of a good research methodology that can be adapted in any Software Engineering (SE) research domain that required a few artifacts to be generated such as use case modeling, misuse case modeling, activity diagram, and initial class diagram from a list of requirements as identified earlier by the SE researchers

  7. Polarizable six-point water models from computational and empirical optimization.

    PubMed

    Tröster, Philipp; Lorenzen, Konstantin; Tavan, Paul

    2014-02-13

    Tröster et al. (J. Phys. Chem B 2013, 117, 9486-9500) recently suggested a mixed computational and empirical approach to the optimization of polarizable molecular mechanics (PMM) water models. In the empirical part the parameters of Buckingham potentials are optimized by PMM molecular dynamics (MD) simulations. The computational part applies hybrid calculations, which combine the quantum mechanical description of a H2O molecule by density functional theory (DFT) with a PMM model of its liquid phase environment generated by MD. While the static dipole moments and polarizabilities of the PMM water models are fixed at the experimental gas phase values, the DFT/PMM calculations are employed to optimize the remaining electrostatic properties. These properties cover the width of a Gaussian inducible dipole positioned at the oxygen and the locations of massless negative charge points within the molecule (the positive charges are attached to the hydrogens). The authors considered the cases of one and two negative charges rendering the PMM four- and five-point models TL4P and TL5P. Here we extend their approach to three negative charges, thus suggesting the PMM six-point model TL6P. As compared to the predecessors and to other PMM models, which also exhibit partial charges at fixed positions, TL6P turned out to predict all studied properties of liquid water at p0 = 1 bar and T0 = 300 K with a remarkable accuracy. These properties cover, for instance, the diffusion constant, viscosity, isobaric heat capacity, isothermal compressibility, dielectric constant, density, and the isobaric thermal expansion coefficient. This success concurrently provides a microscopic physical explanation of corresponding shortcomings of previous models. It uniquely assigns the failures of previous models to substantial inaccuracies in the description of the higher electrostatic multipole moments of liquid phase water molecules. Resulting favorable properties concerning the transferability to other temperatures and conditions like the melting of ice are also discussed.

  8. Centrosomes are autocatalytic droplets of pericentriolar material organized by centrioles

    PubMed Central

    Zwicker, David; Decker, Markus; Jaensch, Steffen; Hyman, Anthony A.; Jülicher, Frank

    2014-01-01

    Centrosomes are highly dynamic, spherical organelles without a membrane. Their physical nature and their assembly are not understood. Using the concept of phase separation, we propose a theoretical description of centrosomes as liquid droplets. In our model, centrosome material occurs in a form soluble in the cytosol and a form that tends to undergo phase separation from the cytosol. We show that an autocatalytic chemical transition between these forms accounts for the temporal evolution observed in experiments. Interestingly, the nucleation of centrosomes can be controlled by an enzymatic activity of the centrioles, which are present at the core of all centrosomes. This nonequilibrium feature also allows for multiple stable centrosomes, a situation that is unstable in equilibrium phase separation. Our theory explains the growth dynamics of centrosomes for all cell sizes down to the eight-cell stage of the Caenorhabditis elegans embryo, and it also accounts for data acquired in experiments with aberrant numbers of centrosomes and altered cell volumes. Furthermore, the model can describe unequal centrosome sizes observed in cells with perturbed centrioles. We also propose an interpretation of the molecular details of the involved proteins in the case of C. elegans. Our example suggests a general picture of the organization of membraneless organelles. PMID:24979791

  9. Improving flow distribution in influent channels using computational fluid dynamics.

    PubMed

    Park, No-Suk; Yoon, Sukmin; Jeong, Woochang; Lee, Seungjae

    2016-10-01

    Although the flow distribution in an influent channel where the inflow is split into each treatment process in a wastewater treatment plant greatly affects the efficiency of the process, and a weir is the typical structure for the flow distribution, to the authors' knowledge, there is a paucity of research on the flow distribution in an open channel with a weir. In this study, the influent channel of a real-scale wastewater treatment plant was used, installing a suppressed rectangular weir that has a horizontal crest to cross the full channel width. The flow distribution in the influent channel was analyzed using a validated computational fluid dynamics model to investigate (1) the comparison of single-phase and two-phase simulation, (2) the improved procedure of the prototype channel, and (3) the effect of the inflow rate on flow distribution. The results show that two-phase simulation is more reliable due to the description of the free-surface fluctuations. It should first be considered for improving flow distribution to prevent a short-circuit flow, and the difference in the kinetic energy with the inflow rate makes flow distribution trends different. The authors believe that this case study is helpful for improving flow distribution in an influent channel.

  10. First-order curvature corrections to the surface tension of multicomponent systems.

    PubMed

    Boltachev, Grey Sh; Baidakov, Vladimir G; Schmelzer, Jürn W P

    2003-08-01

    The dependence of surface tension on curvature is investigated for the case of an equilibrium phase coexistence in multicomponent systems. Employing Gibbs's method of description of heterogeneous systems, an equation is derived to determine the dependence of surface tension on curvature for widely arbitrary paths of variation of the independent thermodynamic parameters. It is supposed hereby merely that the temperature is kept constant and that the variations of the different molar fractions are such that the radius of the dividing surface varies monotonically in dependence on the change of the state parameters of the ambient phase along any of the chosen paths. In the analysis, an approach developed by Blokhuis and Bedeaux for one-component systems is utilized. It relies on the expansion of the surface free energy on curvature of the dividing surface. An equation is derived that connects the first-order correction term in the expansion with the interaction potential of the particles in the multicomponent solution and with the two-particle distribution functions in the planar interfacial layer between the two phases coexisting in equilibrium at planar interfaces. The connection of the first-order curvature correction to the surface tension and the first moment of the pressure tensor at a planar interface is analyzed as well.

  11. Dynamically flavored description of holographic QCD in the presence of a magnetic field

    NASA Astrophysics Data System (ADS)

    Li, Si-wen; Jia, Tuo

    2017-09-01

    We construct the gravitational solution of the Witten-Sakai-Sugimoto model by introducing a magnetic field on the flavor brane. Taking into account their backreaction, we re-solve type IIA supergravity in the presence of a magnetic field. Our calculation shows that the gravitational solutions are magnetically dependent and analytic both in the bubble (confined) and black brane (deconfined) case. We study the dual field theory at the leading order in the ratio of the number of flavors and colors, and also in the Veneziano limit. Some physical properties related to the hadronic physics in an external magnetic field are discussed by using our confined backreaction solution holographically. We also investigate the thermodynamics and holographic renormalization of this model in both phases by our solution. Since the backreaction of the magnetic field is considered in our gravitational solution, it allows us to study the Hawking-Page transition with flavors and colors of this model in the presence of the magnetic field. Finally we therefore obtain the holographic phase diagram with the contributions from the flavors and the magnetic field. Our holographic phase diagram is in qualitative agreement with the lattice QCD result, which thus can be interpreted as the inhibition of confinement or chirally broken symmetry by the magnetic field.

  12. Particle merging algorithm for PIC codes

    NASA Astrophysics Data System (ADS)

    Vranic, M.; Grismayer, T.; Martins, J. L.; Fonseca, R. A.; Silva, L. O.

    2015-06-01

    Particle-in-cell merging algorithms aim to resample dynamically the six-dimensional phase space occupied by particles without distorting substantially the physical description of the system. Whereas various approaches have been proposed in previous works, none of them seemed to be able to conserve fully charge, momentum, energy and their associated distributions. We describe here an alternative algorithm based on the coalescence of N massive or massless particles, considered to be close enough in phase space, into two new macro-particles. The local conservation of charge, momentum and energy are ensured by the resolution of a system of scalar equations. Various simulation comparisons have been carried out with and without the merging algorithm, from classical plasma physics problems to extreme scenarios where quantum electrodynamics is taken into account, showing in addition to the conservation of local quantities, the good reproducibility of the particle distributions. In case where the number of particles ought to increase exponentially in the simulation box, the dynamical merging permits a considerable speedup, and significant memory savings that otherwise would make the simulations impossible to perform.

  13. Experimental and Numerical Modeling of Fluid Flow Processes in Continuous Casting: Results from the LIMMCAST-Project

    NASA Astrophysics Data System (ADS)

    Timmel, K.; Kratzsch, C.; Asad, A.; Schurmann, D.; Schwarze, R.; Eckert, S.

    2017-07-01

    The present paper reports about numerical simulations and model experiments concerned with the fluid flow in the continuous casting process of steel. This work was carried out in the LIMMCAST project in the framework of the Helmholtz alliance LIMTECH. A brief description of the LIMMCAST facilities used for the experimental modeling at HZDR is given here. Ultrasonic and inductive techniques and the X-ray radioscopy were employed for flow measurements or visualizations of two-phase flow regimes occurring in the submerged entry nozzle and the mold. Corresponding numerical simulations were performed at TUBAF taking into account the dimensions and properties of the model experiments. Numerical models were successfully validated using the experimental data base. The reasonable and in many cases excellent agreement of numerical with experimental data allows to extrapolate the models to real casting configurations. Exemplary results will be presented here showing the effect of electromagnetic brakes or electromagnetic stirrers on the flow in the mold or illustrating the properties of two-phase flows resulting from an Ar injection through the stopper rod.

  14. A group contribution method for associating chain molecules based on the statistical associating fluid theory (SAFT-γ)

    NASA Astrophysics Data System (ADS)

    Lymperiadis, Alexandros; Adjiman, Claire S.; Galindo, Amparo; Jackson, George

    2007-12-01

    A predictive group-contribution statistical associating fluid theory (SAFT-γ) is developed by extending the molecular-based SAFT-VR equation of state [A. Gil-Villegas et al. J. Chem. Phys. 106, 4168 (1997)] to treat heteronuclear molecules which are formed from fused segments of different types. Our models are thus a heteronuclear generalization of the standard models used within SAFT, comparable to the optimized potentials for the liquid state OPLS models commonly used in molecular simulation; an advantage of our SAFT-γ over simulation is that an algebraic description for the thermodynamic properties of the model molecules can be developed. In our SAFT-γ approach, each functional group in the molecule is modeled as a united-atom spherical (square-well) segment. The different groups are thus characterized by size (diameter), energy (well depth) and range parameters representing the dispersive interaction, and by shape factor parameters (which denote the extent to which each group contributes to the overall molecular properties). For associating groups a number of bonding sites are included on the segment: in this case the site types, the number of sites of each type, and the appropriate association energy and range parameters also have to be specified. A number of chemical families (n-alkanes, branched alkanes, n-alkylbenzenes, mono- and diunsaturated hydrocarbons, and n-alkan-1-ols) are treated in order to assess the quality of the SAFT-γ description of the vapor-liquid equilibria and to estimate the parameters of various functional groups. The group parameters for the functional groups present in these compounds (CH3, CH2, CH3CH, ACH, ACCH2, CH2, CH , and OH) together with the unlike energy parameters between groups of different types are obtained from an optimal description of the pure component phase equilibria. The approach is found to describe accurately the vapor-liquid equilibria with an overall %AAD of 3.60% for the vapor pressure and 0.86% for the saturated liquid density. The fluid phase equilibria of some larger compounds comprising these groups, which are not included in the optimization database and some binary mixtures are examined to confirm the predictive capability of the SAFT-γ approach. A key advantage of our method is that the binary interaction parameters between groups can be estimated directly from an examination of pure components alone. This means that as a first approximation the fluid-phase equilibria of mixtures of compounds comprising the groups considered can be predicted without the need for any adjustment of the binary interaction parameters (which is common in other approaches). The special case of molecular models comprising tangentially bonded (all-atom and united-atom) segments is considered separately; we comment on the adequacy of such models in representing the properties of real molecules.

  15. A group contribution method for associating chain molecules based on the statistical associating fluid theory (SAFT-gamma).

    PubMed

    Lymperiadis, Alexandros; Adjiman, Claire S; Galindo, Amparo; Jackson, George

    2007-12-21

    A predictive group-contribution statistical associating fluid theory (SAFT-gamma) is developed by extending the molecular-based SAFT-VR equation of state [A. Gil-Villegas et al. J. Chem. Phys. 106, 4168 (1997)] to treat heteronuclear molecules which are formed from fused segments of different types. Our models are thus a heteronuclear generalization of the standard models used within SAFT, comparable to the optimized potentials for the liquid state OPLS models commonly used in molecular simulation; an advantage of our SAFT-gamma over simulation is that an algebraic description for the thermodynamic properties of the model molecules can be developed. In our SAFT-gamma approach, each functional group in the molecule is modeled as a united-atom spherical (square-well) segment. The different groups are thus characterized by size (diameter), energy (well depth) and range parameters representing the dispersive interaction, and by shape factor parameters (which denote the extent to which each group contributes to the overall molecular properties). For associating groups a number of bonding sites are included on the segment: in this case the site types, the number of sites of each type, and the appropriate association energy and range parameters also have to be specified. A number of chemical families (n-alkanes, branched alkanes, n-alkylbenzenes, mono- and diunsaturated hydrocarbons, and n-alkan-1-ols) are treated in order to assess the quality of the SAFT-gamma description of the vapor-liquid equilibria and to estimate the parameters of various functional groups. The group parameters for the functional groups present in these compounds (CH(3), CH(2), CH(3)CH, ACH, ACCH(2), CH(2)=, CH=, and OH) together with the unlike energy parameters between groups of different types are obtained from an optimal description of the pure component phase equilibria. The approach is found to describe accurately the vapor-liquid equilibria with an overall %AAD of 3.60% for the vapor pressure and 0.86% for the saturated liquid density. The fluid phase equilibria of some larger compounds comprising these groups, which are not included in the optimization database and some binary mixtures are examined to confirm the predictive capability of the SAFT-gamma approach. A key advantage of our method is that the binary interaction parameters between groups can be estimated directly from an examination of pure components alone. This means that as a first approximation the fluid-phase equilibria of mixtures of compounds comprising the groups considered can be predicted without the need for any adjustment of the binary interaction parameters (which is common in other approaches). The special case of molecular models comprising tangentially bonded (all-atom and united-atom) segments is considered separately; we comment on the adequacy of such models in representing the properties of real molecules.

  16. Job Aid Manuals for Phase II--DESIGN of the Instructional Systems Development Model.

    ERIC Educational Resources Information Center

    Schulz, Russel E.; Farrell, Jean R.

    Designed to supplement the descriptive authoring flowcharts presented in a companion volume, this manual includes specific guidance, examples, and other information referred to in the flowcharts for the implementation of the second phase of the Instructional Systems Development Model (ISD). The introductory section includes definitions;…

  17. Florida Schoolhouse Systems Project. First Phase Report.

    ERIC Educational Resources Information Center

    Florida State Dept. of Education, Tallahassee.

    A description is presented of the first phase of the Florida Schoolhouse Systems Project. Following a presentation of the background and objectives of the SSP, the development of integrated building systems is considered with regard to--(1) stimulation of research and development, (2) performance specifications and competitive bidding, and (3)…

  18. Tilesetting. Pre-Apprenticeship Phase 2 Training. Instructor's Guide.

    ERIC Educational Resources Information Center

    Ausland, Greg

    This instructor's guide accompanies the self-paced student training modules on tilesetting, available separately as CE 031 564. Introductory materials include a description of the components of the pre-apprenticeship project, discussion of teacher's role in students' completion of the modules, and scope and contents of Phase 2 training. Each of…

  19. Survival Skills. Pre-Apprenticeship Phase 2 Training. Instructors Guide

    ERIC Educational Resources Information Center

    Lane Community Coll., Eugene, OR.

    This instructor's guide contains the 43 Survival Skills modules developed for Pre-Apprenticeship Phase 2 Training. Introductory materials include a description of components of the pre-apprenticeship project, recommendations for module implementation, and synopses of the modules that were developed to prompt social skills development. Each module…

  20. Consumer Fraud: An Empirical Perspective. Summary.

    ERIC Educational Resources Information Center

    Schubert, Jane G.; And Others

    The American Institutes for Research (AIR) and the National Consumer Law Center (NCLC) studied consumer fraud and assessed possible intervention. Phase I produced an AIR description of the nature, scope, and characteristics of consumer fraud and an NCLC compilation of the laws and regulations which control it. In Phase II AIR developed…

  1. On the Decision-Making Process in Music Education.

    ERIC Educational Resources Information Center

    Jorgensen, Estelle R.

    1985-01-01

    Sketches a conceptual framework for the systematic description of decision-making processes in music education. Refers to existing formulations in education, management, marketing, and economics. Lists decision-making phases in music education, each exhibiting the characteristics of a social system. Offers a historical example of each phase. (AYC)

  2. Job Aid Manuals for Phase III--DEVELOP of the Instructional Systems Development Model.

    ERIC Educational Resources Information Center

    Schulz, Russel E.; Farrell, Jean R.

    Designed to supplement the descriptive authoring flowcharts presented in a companion volume, this manual includes specific guidance, examples, and other information referred to in the flowcharts for the implementation of the third phase of the Instructional Systems Development Model (ISD). The introductory section includes definitions;…

  3. Low pressure bottom-up synthesis of metal@oxide and oxide nanoparticles: control of structure and functional properties

    NASA Astrophysics Data System (ADS)

    D'Addato, Sergio; Chiara Spadaro, Maria

    2018-03-01

    Experimental activity on core@shell, metal@oxide, and oxide nanoparticles (NPs) grown with physical synthesis, and more specifically by low pressure gas aggregation sources (LPGAS) is reviewed, through a selection of examples encompassing some potential applications in nanotechnology. After an introduction to the applications of NPs, a brief description of the main characteristics of the growth process of clusters and NPs in LPGAS is given. Thereafter, some relevant case studies are reported: • Formation of native oxide shells around the metal cores in core@shell NPs. • Experimental efforts to obtain magnetic stabilization in magnetic core@shell NPs by controlling their structure and morphology. • Recent advancements in NP source design and new techniques of co-deposition, with relevant results in the realization of NPs with a greater variety of functionalities. • Recent results on reducible oxide NPs, with potentialities in nanocatalysis, energy storage, and other applications. Although this list is far from being exhaustive, the aim of the authors is to provide the reader a descriptive glimpse into the physics behind the growth and studies of low pressure gas-phase synthesized NPs, with their ever-growing potentialities for the rational design of new functional materials.

  4. A descriptive model of preventability in maternal morbidity and mortality.

    PubMed

    Geller, S E; Cox, S M; Kilpatrick, S J

    2006-02-01

    To develop a descriptive model of preventability for maternal morbidity and mortality that can be used in quality assurance and morbidity and mortality review processes. This descriptive study was part of a larger case-control study conducted at the University of Illinois at Chicago in which maternal deaths were cases and women with severe maternal morbidity served as controls. Morbidities and mortalities were classified by a team of clinicians as preventable or not preventable. Qualitative analysis of data was conducted to identify and categorize different types of preventable events. Of 237 women, there were 79 women with preventable events attributable to provider or system factors. The most common types of preventable events were inadequate diagnosis/recognition of high-risk (54.4%), treatment (38.0%), and documentation (30.7%). A descriptive model was illustrated that can be used to categorize preventable events in maternal morbidity and mortality and can be incorporated into quality assurance and clinical case review to enhance the monitoring of hospital-based obstetric care and to decrease medical error.

  5. Acromegaly and gigantism in the medical literature. Case descriptions in the era before and the early years after the initial publication of Pierre Marie (1886).

    PubMed

    de Herder, Wouter W

    2009-01-01

    In 1886 Pierre Marie used the term "acromegaly" for the first time and gave a full description of the characteristic clinical picture. However several others had already given clear clinical descriptions before him and sometimes had given the disease other names. After 1886, it gradually became clear that pituitary enlargement (caused by a pituitary adenoma) was the cause and not the consequence of acromegaly, as initially thought. Pituitary adenomas could be found in the great majority of cases. It also became clear that acromegaly and gigantism were the same disease but occurring at different stages of life and not different diseases as initially thought. At the end of the 19th and beginning of the 20th century most information was derived from case descriptions and post-mortem examinations of patients with acromegaly or (famous) patients with gigantism. The stage was set for further research into the pathogenesis, diagnosis and therapy of acromegaly and gigantism.

  6. Distribution of causes of maternal mortality during delivery and post-partum: results of an African multicentre hospital-based study.

    PubMed

    Thonneau, Patrick F; Matsudai, Tomohiro; Alihonou, Eusèbe; De Souza, Jose; Faye, Ousseynou; Moreau, Jean-Charles; Djanhan, Yao; Welffens-Ekra, Christiane; Goyaux, Nathalie

    2004-06-15

    To assess the maternal mortality ratio in maternity units of reference hospitals in large west African cities, and to describe the distribution of complications and causes of maternal deaths. Prospective descriptive study in twelve reference maternities located in three African countries (Benin, Ivory Coast, Senegal). Data (clinical findings at hospital entry, medical history, complications, type of surgery, vital status of the women at discharge) were collected from obstetrical and surgical files and from admission hospital registers. All cases of maternal deaths were systematically reviewed by African and European staff. Of a total of 10,515 women, 1495 presented a major obstetric complication with dystocia or inappropriate management of the labour phase as the leading cause. Eighty-five maternal deaths were reported, giving a global hospital-based maternal mortality ratio of 800/100,000. Hypertensive disorders were involved in 25/85 cases (29%) and post-partum haemorrhage in 13/85 cases (15%). Relatively few cases (14) of major sepsis were reported, leading to three maternal deaths. The results of this multicentre study confirm the high rates of maternal mortality in maternity units of reference hospitals in large African cities, and in addition to dystocia the contribution of hypertensive disorders and post-partum haemorrhage to maternal deaths.

  7. Regional Military Integration in West Africa: A Case Study of the Multi-National Joint Task Force in the Fight against Boko Haram

    DTIC Science & Technology

    2016-06-10

    detailed description of issues surrounding a subject matter. The use of case studies provides the experimental foundation for qualitative analysis. As...The chapter provided a description of the case studies -based QCA methodology, highlighted how the Charles Ragin QCA will be used for data analysis...world. Against this backdrop, a study assessing the challenges and prospects of sub- regional post -conflict peacebuilding efforts will not only be

  8. Relativistic Quark Model Based Description of Low Energy NN Scattering

    NASA Astrophysics Data System (ADS)

    Antalik, R.; Lyubovitskij, V. E.

    A model describing the NN scattering phase shifts is developed. Two nucleon interactions induced by meson exchange forces are constructed starting from π, η, η‧ pseudoscalar-, the ρ, ϕ, ω vector-, and the ɛ(600), a0, f0(1400) scalar — meson-nucleon coupling constants, which we obtained within a relativistic quantum field theory based quark model. Working within the Blankenbecler-Sugar-Logunov-Tavkhelidze quasipotential dynamics, we describe the NN phase shifts in a relativistically invariant way. In this procedure we use phenomenological form factor cutoff masses and effective ɛ and ω meson-nucleon coupling constants, only. Resulting NN phase shifts are in a good agreement with both, the empirical data, and the entirely phenomenological Bonn OBEP model fit. While the quality of our description, evaluated as a ratio of our results to the Bonn OBEP model χ2 ones is about 1.2, other existing (semi)microscopic results gave qualitative results only.

  9. Case-based ethics instruction: the influence of contextual and individual factors in case content on ethical decision-making.

    PubMed

    Bagdasarov, Zhanna; Thiel, Chase E; Johnson, James F; Connelly, Shane; Harkrider, Lauren N; Devenport, Lynn D; Mumford, Michael D

    2013-09-01

    Cases have been employed across multiple disciplines, including ethics education, as effective pedagogical tools. However, the benefit of case-based learning in the ethics domain varies across cases, suggesting that not all cases are equal in terms of pedagogical value. Indeed, case content appears to influence the extent to which cases promote learning and transfer. Consistent with this argument, the current study explored the influences of contextual and personal factors embedded in case content on ethical decision-making. Cases were manipulated to include a clear description of the social context and the goals of the characters involved. Results indicated that social context, specifically the description of an autonomy-supportive environment, facilitated execution of sense making processes and resulted in greater decision ethicality. Implications for designing optimal cases and case-based training programs are discussed.

  10. Ice Growth Measurements from Image Data to Support Ice Crystal and Mixed-Phase Accretion Testing

    NASA Technical Reports Server (NTRS)

    Struk, Peter M.; Lynch, Christopher J.

    2012-01-01

    This paper describes the imaging techniques as well as the analysis methods used to measure the ice thickness and growth rate in support of ice-crystal icing tests performed at the National Research Council of Canada (NRC) Research Altitude Test Facility (RATFac). A detailed description of the camera setup, which involves both still and video cameras, as well as the analysis methods using the NASA Spotlight software, are presented. Two cases, one from two different test entries, showing significant ice growth are analyzed in detail describing the ice thickness and growth rate which is generally linear. Estimates of the bias uncertainty are presented for all measurements. Finally some of the challenges related to the imaging and analysis methods are discussed as well as methods used to overcome them.

  11. Ice Growth Measurements from Image Data to Support Ice-Crystal and Mixed-Phase Accretion Testing

    NASA Technical Reports Server (NTRS)

    Struk, Peter, M; Lynch, Christopher, J.

    2012-01-01

    This paper describes the imaging techniques as well as the analysis methods used to measure the ice thickness and growth rate in support of ice-crystal icing tests performed at the National Research Council of Canada (NRC) Research Altitude Test Facility (RATFac). A detailed description of the camera setup, which involves both still and video cameras, as well as the analysis methods using the NASA Spotlight software, are presented. Two cases, one from two different test entries, showing significant ice growth are analyzed in detail describing the ice thickness and growth rate which is generally linear. Estimates of the bias uncertainty are presented for all measurements. Finally some of the challenges related to the imaging and analysis methods are discussed as well as methods used to overcome them.

  12. A Case Study on Teaching of Energy as a Subject for 9th Graders

    ERIC Educational Resources Information Center

    Bezen, Sevim; Bayrak, Celal; Aykutlu, Isil

    2017-01-01

    This study aims to describe how energy subject is taught in 9th grades. The study is designed as a descriptive case study with the participation of 3 physics teachers and 85 students. Data were obtained through observation, interviews, and documents, and they were analyzed through descriptive analysis method. In the observations made at the…

  13. A Qualitative Descriptive Case Study of the Requirements of the IT Industry for Entry-Level IT Positions

    ERIC Educational Resources Information Center

    Feuerherm, Todd Michael

    2009-01-01

    This qualitative descriptive case study explored the requirements of the IT industry for education, IT certification, and work experience for entry-level IT professionals. Research has shown a growing problem where IT graduates were not able to meet the requirements for entry-level IT jobs. IT enrollment has decreased considerably over the past…

  14. An Investigation of a Virtual School Program in One Public School District in Texas: A Descriptive Case Study

    ERIC Educational Resources Information Center

    Quadri, Rizvan

    2012-01-01

    This qualitative, descriptive case study employed the use of narrative to investigate a virtual school program in a public school district in Texas. A focus group interviewing process was used to interview the participants. Findings from this study conclude that with continued support from district leaders, along with having the appropriate…

  15. Incorporating Descriptive Assessment Results into the Design of a Functional Analysis: A Case Example Involving a Preschooler's Hand Mouthing

    ERIC Educational Resources Information Center

    Tiger, Jeffrey H.; Hanley, Gregory P.; Bessette, Kimberly K.

    2006-01-01

    Functional analysis methodology has become the hallmark of behavioral assessment, yielding a determination of behavioral function in roughly 96% of the cases published (Hanley, Iwata, & McCord, 2003). Some authors have suggested that incorporating the results of a descriptive assessment into the design of a functional analysis may be useful in…

  16. Generic Argillite/Shale Disposal Reference Case

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

    Zheng, Liange; Colon, Carlos Jové; Bianchi, Marco

    Radioactive waste disposal in a deep subsurface repository hosted in clay/shale/argillite is a subject of widespread interest given the desirable isolation properties, geochemically reduced conditions, and widespread geologic occurrence of this rock type (Hansen 2010; Bianchi et al. 2013). Bianchi et al. (2013) provides a description of diffusion in a clay-hosted repository based on single-phase flow and full saturation using parametric data from documented studies in Europe (e.g., ANDRA 2005). The predominance of diffusive transport and sorption phenomena in this clay media are key attributes to impede radionuclide mobility making clay rock formations target sites for disposal of high-level radioactivemore » waste. The reports by Hansen et al. (2010) and those from numerous studies in clay-hosted underground research laboratories (URLs) in Belgium, France and Switzerland outline the extensive scientific knowledge obtained to assess long-term clay/shale/argillite repository isolation performance of nuclear waste. In the past several years under the UFDC, various kinds of models have been developed for argillite repository to demonstrate the model capability, understand the spatial and temporal alteration of the repository, and evaluate different scenarios. These models include the coupled Thermal-Hydrological-Mechanical (THM) and Thermal-Hydrological-Mechanical-Chemical (THMC) models (e.g. Liu et al. 2013; Rutqvist et al. 2014a, Zheng et al. 2014a) that focus on THMC processes in the Engineered Barrier System (EBS) bentonite and argillite host hock, the large scale hydrogeologic model (Bianchi et al. 2014) that investigates the hydraulic connection between an emplacement drift and surrounding hydrogeological units, and Disposal Systems Evaluation Framework (DSEF) models (Greenberg et al. 2013) that evaluate thermal evolution in the host rock approximated as a thermal conduction process to facilitate the analysis of design options. However, the assumptions and the properties (parameters) used in these models are different, which not only make inter-model comparisons difficult, but also compromise the applicability of the lessons learned from one model to another model. The establishment of a reference case would therefore be helpful to set up a baseline for model development. A generic salt repository reference case was developed in Freeze et al. (2013) and the generic argillite repository reference case is presented in this report. The definition of a reference case requires the characterization of the waste inventory, waste form, waste package, repository layout, EBS backfill, host rock, and biosphere. This report mainly documents the processes in EBS bentonite and host rock that are potentially important for performance assessment and properties that are needed to describe these processes, with brief description other components such as waste inventory, waste form, waste package, repository layout, aquifer, and biosphere. A thorough description of the generic argillite repository reference case will be given in Jové Colon et al. (2014).« less

  17. DRFM Cordic Processor and Sea Clutter Modeling for Enhancing Structured False Target Synthesis

    DTIC Science & Technology

    2017-09-01

    was implemented using the Verilog hardware description language. The second investigation concerns generating sea clutter to impose on the false target...to achieve accuracy at 5.625o. The resulting design was implemented using the Verilog hardware description language. The second investigation...33 3. Initialization of the Angle Accumulator ....................................34 4. Design Methodology for I/Q Phase

  18. Sorption Equilibria of Vapor Phase Organic Pollutants on Unsaturated Soils and Soil Minerals

    DTIC Science & Technology

    1990-04-01

    Sorbent Characterization .. ........ .......... 6 a. Description of Inorganic Solids and Soils. .... ........ 6 b. Moisture Content...compounds (TCE and toluene) is compared for a cored depth profile obtained from an unsaturated soil and for simulated profiles using inorganic solids. The...Sorbent Characterization a. Description of Inorganic Solids and Soils Inorganic solids were used for initial sorption studies to develop experimental

  19. Extraarticular variants of the long head of the biceps brachii: a reminder of embryology.

    PubMed

    Audenaert, Emmanuel A; Barbaix, Erik J; Van Hoonacker, Petrus; Berghs, Bart M

    2008-01-01

    Developmental anomalies of the long head of the biceps tendon are rare and have been described in the literature mainly dealing with anatomy and embryology. Because most basic embryologic research on this topic was conducted before 1966, a literature search was performed from archived anatomy textbooks and manuscript references. These data were compared with the scarce case descriptions of developmental anomalies of the long head of the biceps tendon. An additional case illustration from our own experience was provided. From the literature, it appears that during the embryologic phase of development, a staged migration of the long head of the biceps tendon occurs from a position between the fibrous capsule and synovial layer to an intraarticular position. Recent anatomic and arthroscopic case reports have shown that interruption of this migration can occur in any of these stages. Given the recent increase in arthroscopic shoulder surgery, anomalies of the long head of the biceps tendon will be encountered more frequently. Knowledge of their existence and origin can help in evaluating unexpected anatomic variations or the absence of the biceps tendon in preoperative medical imaging or during an arthroscopic procedure.

  20. The cleanroom case study in the Software Engineering Laboratory: Project description and early analysis

    NASA Technical Reports Server (NTRS)

    Green, Scott; Kouchakdjian, Ara; Basili, Victor; Weidow, David

    1990-01-01

    This case study analyzes the application of the cleanroom software development methodology to the development of production software at the NASA/Goddard Space Flight Center. The cleanroom methodology emphasizes human discipline in program verification to produce reliable software products that are right the first time. Preliminary analysis of the cleanroom case study shows that the method can be applied successfully in the FDD environment and may increase staff productivity and product quality. Compared to typical Software Engineering Laboratory (SEL) activities, there is evidence of lower failure rates, a more complete and consistent set of inline code documentation, a different distribution of phase effort activity, and a different growth profile in terms of lines of code developed. The major goals of the study were to: (1) assess the process used in the SEL cleanroom model with respect to team structure, team activities, and effort distribution; (2) analyze the products of the SEL cleanroom model and determine the impact on measures of interest, including reliability, productivity, overall life-cycle cost, and software quality; and (3) analyze the residual products in the application of the SEL cleanroom model, such as fault distribution, error characteristics, system growth, and computer usage.

  1. Beginning Teacher Evaluation Study: Phase II, 1973-74, Final Report: Volume III.2. Reading and Mathematics Observation System: Description and Analysis of Time Expenditures.

    ERIC Educational Resources Information Center

    Calfee, Robert; Calfee, Kathryn Hoover

    The Beginning Teacher Evaluation Study (BTES), Phase II, was a research project on effective teaching behavior--what teachers do that significantly affects what and how pupils learn. The purposes of Phase II were to (1) develop an assessment system for measuring teacher and pupil behaviors and other factors which could influence each of them and…

  2. Functional Description for the Department of the Army Movements Management System. Redesign Phase 1 (DAMMS-R1). Volume 2.

    DTIC Science & Technology

    1987-12-31

    Spot--Limit-Cal Print-Spot-Limit-Cal PART OF: MNar-t-Origri-Frt-Data 111-780 Syste-, < fvii -Hy-Asset-Forecast-Inp> -Operator 7’-4 :11-781 ADSM 18-LZ4-AKM...DEFINE PROCESS Maint-SpotFactor-Tbl DESCRIPTION; Maintain Spot Factor Table. This is an interactive process that receives SpotFactorCd(s) and...PROCESS Update-SpotFactor-Tbi DESCRIPTION; Update Spot Factor Table. This is a batch process that creates records or changes existing records in the

  3. A comparison of Redlich-Kister polynomial and cubic spline representations of the chemical potential in phase field computations

    DOE PAGES

    Teichert, Gregory H.; Gunda, N. S. Harsha; Rudraraju, Shiva; ...

    2016-12-18

    Free energies play a central role in many descriptions of equilibrium and non-equilibrium properties of solids. Continuum partial differential equations (PDEs) of atomic transport, phase transformations and mechanics often rely on first and second derivatives of a free energy function. The stability, accuracy and robustness of numerical methods to solve these PDEs are sensitive to the particular functional representations of the free energy. In this communication we investigate the influence of different representations of thermodynamic data on phase field computations of diffusion and two-phase reactions in the solid state. First-principles statistical mechanics methods were used to generate realistic free energymore » data for HCP titanium with interstitially dissolved oxygen. While Redlich-Kister polynomials have formed the mainstay of thermodynamic descriptions of multi-component solids, they require high order terms to fit oscillations in chemical potentials around phase transitions. Here, we demonstrate that high fidelity fits to rapidly fluctuating free energy functions are obtained with spline functions. As a result, spline functions that are many degrees lower than Redlich-Kister polynomials provide equal or superior fits to chemical potential data and, when used in phase field computations, result in solution times approaching an order of magnitude speed up relative to the use of Redlich-Kister polynomials.« less

  4. Combustion mechanism of double-base propellant containing nitrogen heterocyclic nitroamines (II): The temperature distribution of the flame and its chemical structure

    NASA Astrophysics Data System (ADS)

    Yan, Qi-Long; Song, Zhen-Wei; Shi, Xiao-Bing; Yang, Zhi-Yuan; Zhang, Xiao-Hong

    2009-03-01

    In order to evaluate the actual pros and cons in the use of new nitroamines for solid rocket applications, the combustion properties of double-base propellants containing nitrogen heterocyclic nitroamines such as RDX, TNAD, HMX and DNP are investigated by means of high-speed photography technique, Non-contact wavelet-based measurement of flame temperature distribution. The chemical reactions in different combustion zone which control the burning characteristics of the double-base propellant containing nitrogen heterocyclic nitroamines were systematically investigated and descriptions of the detailed thermal decomposition mechanisms from solid phase to liquid phase or to gas phase are also included. It was indicated that the thermodynamic phase transition consisting of both evaporation and condensation of NC+NG, HMX, TNAD, RDX and DNP, are considered to provide a complete description of the mass transfer process in the combustion of these double-base propellants, and the combustion mechanisms of them are mainly involved with the oxidation mechanism of the NO 2, formaldehyde (CH 2O) and hydrogen cyanide (HCN). The entire oxidation reaction rate might be dependent on the pressure of the combustion chamber and temperature of the gas phase.

  5. Theoretical model for the discrete flexoelectric effect and a description for the sequence of intermediate smectic phases with increasing periodicity.

    PubMed

    Emelyanenko, A V; Osipov, M A

    2003-11-01

    A general phenomenological description and a simple molecular model is proposed for the "discrete" flexoelectric effect in tilted smectic liquid crystal phases. This effect defines a polarization in a smectic layer induced by a difference of director orientations in the two smectic layers adjacent to it. It is shown that the "discrete" flexoelectric effect is determined by electrostatic dipole-quadrupole interaction between positionally correlated molecules located in adjacent smectic layers, while the corresponding dipole-dipole interaction is responsible for a coupling between polarization vectors in neighboring layers. It is shown that a simple phenomenological model of a ferrielectric smectic liquid crystal, which has recently been proposed in the literature, can be used to describe the whole sequence of intermediate chiral smectic C* phases with increasing periods, and to determine the nonplanar structure of each phase without additional assumptions. In this sequence the phases with three- and four-layer periodicities have the same structure, as observed in the experiment. The theory predicts also the structure of intermediate phases with longer periods that have not been studied experimentally so far. The structures of intermediate phases with periodicities of up to nine layers are presented together with the phase diagrams, and a relationship between molecular chirality and the three-dimensional structure of intermediate phases is discussed. It is considered also how the coupling between the spontaneous polarization determined by molecular chirality and the induced polarization determined by the discrete flexoelectric effect stabilizes the nonplanar structure of intermediate phases.

  6. Interfacial crowding of nanoplatelets in co-continuous polymer blends: assembly, elasticity and structure of the interfacial nanoparticle network.

    PubMed

    Altobelli, R; Salzano de Luna, M; Filippone, G

    2017-09-27

    The sequence of events which leads to the interfacial crowding of plate-like nanoparticles in co-continuous polymer blends is investigated through a combination of morphological and rheological analyses. Very low amounts (∼0.2 vol%) of organo-modified clay are sufficient to suppress phase coarsening in a co-continuous polystyrene/poly(methyl methacrylate) blend, while lower particle loading allows for a tuning of the characteristic size of the polymer phases at the μm-scale. In any case, an interfacial network of nanoparticles eventually forms, which is driven by the preferred polymer-polymer interface. The elastic features and stress-bearing ability of this peculiar nanoparticle assembly are studied in detail by means of a descriptive two-phase viscoelastic model, which allows isolation of the contribution of the filler network. The role of the co-continuous matrix in driving the space arrangement of the nanoparticles is emphasized by means of comparative analysis with systems based on the same polymers and nanoparticles, but in which the matrix is either a pure polymer or a blend with drop-in-matrix morphology. The relaxation dynamics of the interfacial network was found not to depend on the matrix microstructure, which instead substantially affects the assembly of the nanoplatelets. When the host medium is co-continuous, the particles align along the preferred polymer-polymer interface, percolating at a very low amount (∼0.17 vol%) and prevalently interacting edge-to-edge. The stress bearing ability of such a network is much higher than that in the case of matrix based on a homogeneous polymer or a drop-in-matrix blend, but its elasticity shows low sensitivity to the filler content.

  7. Phase walk analysis of leptokurtic time series.

    PubMed

    Schreiber, Korbinian; Modest, Heike I; Räth, Christoph

    2018-06-01

    The Fourier phase information play a key role for the quantified description of nonlinear data. We present a novel tool for time series analysis that identifies nonlinearities by sensitively detecting correlations among the Fourier phases. The method, being called phase walk analysis, is based on well established measures from random walk analysis, which are now applied to the unwrapped Fourier phases of time series. We provide an analytical description of its functionality and demonstrate its capabilities on systematically controlled leptokurtic noise. Hereby, we investigate the properties of leptokurtic time series and their influence on the Fourier phases of time series. The phase walk analysis is applied to measured and simulated intermittent time series, whose probability density distribution is approximated by power laws. We use the day-to-day returns of the Dow-Jones industrial average, a synthetic time series with tailored nonlinearities mimicing the power law behavior of the Dow-Jones and the acceleration of the wind at an Atlantic offshore site. Testing for nonlinearities by means of surrogates shows that the new method yields strong significances for nonlinear behavior. Due to the drastically decreased computing time as compared to embedding space methods, the number of surrogate realizations can be increased by orders of magnitude. Thereby, the probability distribution of the test statistics can very accurately be derived and parameterized, which allows for much more precise tests on nonlinearities.

  8. Predicate Argument Structure Analysis for Use Case Description Modeling

    NASA Astrophysics Data System (ADS)

    Takeuchi, Hironori; Nakamura, Taiga; Yamaguchi, Takahira

    In a large software system development project, many documents are prepared and updated frequently. In such a situation, support is needed for looking through these documents easily to identify inconsistencies and to maintain traceability. In this research, we focus on the requirements documents such as use cases and consider how to create models from the use case descriptions in unformatted text. In the model construction, we propose a few semantic constraints based on the features of the use cases and use them for a predicate argument structure analysis to assign semantic labels to actors and actions. With this approach, we show that we can assign semantic labels without enhancing any existing general lexical resources such as case frame dictionaries and design a less language-dependent model construction architecture. By using the constructed model, we consider a system for quality analysis of the use cases and automated test case generation to keep the traceability between document sets. We evaluated the reuse of the existing use cases and generated test case steps automatically with the proposed prototype system from real-world use cases in the development of a system using a packaged application. Based on the evaluation, we show how to construct models with high precision from English and Japanese use case data. Also, we could generate good test cases for about 90% of the real use cases through the manual improvement of the descriptions based on the feedback from the quality analysis system.

  9. Cold fission description with constant and varying mass asymmetries

    NASA Astrophysics Data System (ADS)

    Duarte, S. B.; Rodríguez, O.; Tavares, O. A. P.; Gonçalves, M.; García, F.; Guzmán, F.

    1998-05-01

    Different descriptions for varying the mass asymmetry in the fragmentation process are used to calculate the cold fission barrier penetrability. The relevance of the appropriate choice for both the description of the prescission phase and inertia coefficient to unify alpha decay, cluster radioactivity, and spontaneous cold fission processes in the same theoretical framework is explicitly shown. We calculate the half-life of all possible partition modes of nuclei of A>200 following the most recent Mass Table by Audi and Wapstra. It is shown that if one uses the description in which the mass asymmetry is maintained constant during the fragmentation process, the experimental half-life values and mass yield of 234U cold fission are satisfactorily reproduced.

  10. Intervention description is not enough: evidence from an in-depth multiple case study on the untold role and impact of context in randomised controlled trials of seven complex interventions

    PubMed Central

    2012-01-01

    Background A number of single case reports have suggested that the context within which intervention studies take place may challenge the assumptions that underpin randomised controlled trials (RCTs). However, the diverse ways in which context may challenge the central tenets of the RCT, and the degree to which this information is known to researchers or subsequently reported, has received much less attention. In this paper, we explore these issues by focusing on seven RCTs of interventions varying in type and degree of complexity, and across diverse contexts. Methods This in-depth multiple case study using interviews, focus groups and documentary analysis was conducted in two phases. In phase one, a RCT of a nurse-led intervention provided a single exploratory case and informed the design, sampling and data collection within the main study. Phase two consisted of a multiple explanatory case study covering a spectrum of trials of different types of complex intervention. A total of eighty-four data sources across the seven trials were accessed. Results We present consistent empirical evidence across all trials to indicate that four key elements of context (personal, organisational, trial and problem context) are crucial to understanding how a complex intervention works and to enable both assessments of internal validity and likely generalisability to other settings. The ways in which context challenged trial operation was often complex, idiosyncratic, and subtle; often falling outside of current trial reporting formats. However, information on such issues appeared to be available via first hand ‘insider accounts’ of each trial suggesting that improved reporting on the role of context is possible. Conclusions Sufficient detail about context needs to be understood and reported in RCTs of complex interventions, in order for the transferability of complex interventions to be assessed. Improved reporting formats that require and encourage the clarification of both general and project-specific threats to the likely internal and external validity need to be developed. In addition, a cultural change is required in which the open and honest reporting of such issues is seen as an indicator of study strength and researcher integrity, rather than a symbol of a poor quality study or investigator ability. PMID:22742939

  11. Nonsingular bouncing cosmology: Consistency of the effective description

    NASA Astrophysics Data System (ADS)

    Koehn, Michael; Lehners, Jean-Luc; Ovrut, Burt

    2016-05-01

    We explicitly confirm that spatially flat nonsingular bouncing cosmologies make sense as effective theories. The presence of a nonsingular bounce in a spatially flat universe implies a temporary violation of the null energy condition, which can be achieved through a phase of ghost condensation. We calculate the scale of strong coupling and demonstrate that the ghost-condensate bounce remains trustworthy throughout, and that all perturbation modes within the regime of validity of the effective description remain under control. For this purpose we require the perturbed action up to third order in perturbations, which we calculate in both flat and co-moving gauge—since these two gauges allow us to highlight different physical aspects. Our conclusion is that there exist healthy descriptions of nonsingular bouncing cosmologies providing a viable resolution of the big-bang singularities in cosmological models. Our results also suggest a variant of ekpyrotic cosmology, in which entropy perturbations are generated during the contracting phase, but are only converted into curvature perturbations after the bounce.

  12. Polymorphous band structure model of gapping in the antiferromagnetic and paramagnetic phases of the Mott insulators MnO, FeO, CoO, and NiO

    NASA Astrophysics Data System (ADS)

    Trimarchi, Giancarlo; Wang, Zhi; Zunger, Alex

    2018-01-01

    The existence of band gaps in both the antiferromagnetic (AFM) and paramagnetic (PM) phases of the classic NaCl-structure Mott insulators MnO, FeO, CoO, and NiO is traditionally viewed and taught as a manifestation of strong correlation whereby insulation results from electrons moving across the lattice forming states with doubly occupied d orbitals on certain atomic sites and empty d orbitals on other sites. Within such theories, the gap of the AFM and PM phases of these oxides emerges even in the absence of spatial symmetry breaking. The need for such a correlated picture is partially based on the known failure of the commonly used band models for the PM phase that assume for such a spin disordered state the macroscopically averaged NaCl structure, where all transition metal (TM) sites are symmetry-equivalent (a monomorphous description), producing a gapless PM state with zero magnetic moments, in sharp conflict with experiment. Here, we seek to understand the minimum theoretical description needed to capture the leading descriptors of ground state Mott insulation in the classic, 3 d monoxide Mott systems—gapping and moment formation in the AFM and PM phase. As noted by previous authors, the spin-ordered AFM phase in these materials already shows in band theory a significant band gap when one doubles the NaCl unit cell by permitting different potentials for transition-metal atoms with different spins. For the spin-disordered PM phase, we allow analogously larger NaCl-type supercells where each TM site can have different spin direction and local bonding environments (i.e., disordered), yet the total spin is zero. Such a polymorphous description has the flexibility to acquire symmetry-breaking energy-lowering patterns that can lift the degeneracy of the d orbitals and develop large on-site magnetic moments without violating the global, averaged NaCl symmetry. Electrons are exchanged between spin-up and spin-down bands to create closed-shell insulating configurations that lend themselves to a single determinental description. It turns out that such a polymorphous description of the structure within the single-determinant, mean-field, Bloch periodic band structure approach (based on DFT +U ) allows large on-site magnetic moments to develop spontaneously, leading to significant (1-3 eV) band gaps and large local moments in the AFM and PM phases of the classic NaCl-structure Mott insulators MnO, FeO, CoO, and NiO in agreement with experiment. We adapt to the spin disordered polymorphous configurations the "special quasirandom structure" (SQS) construct known from the theory of disordered substitutional alloys whereby supercell approximants which represent the best random configuration average (not individual snapshots) for finite (64, 216 atoms, or larger) supercells of a given lattice symmetry are constructed. We conclude that the basic features of these paradigmatic Mott insulators can be approximated by the physics included in energy-lowering symmetry broken DFT.

  13. Drywall. Pre-Apprenticeship Phase 2 Training. Instructor's Guide.

    ERIC Educational Resources Information Center

    Moore, Doug

    This instructor's guide accompanies the self-paced student training modules on drywall available separately as CE 031 574. Introductory materials include a description of the components of the pre-apprenticeship project, discussion of teacher's role in students' completion of the modules, and scope and contents of Phase 2 training. Each of the 18…

  14. Drywall. Pre-Apprenticeship Phase 1 Training. Instructor's Guide.

    ERIC Educational Resources Information Center

    Lane Community Coll., Eugene, OR.

    This instructor's guide accompanies the self-paced student training modules on drywall, one of which is available separately as CE 032 887. Introductory materials include a description of the components of the pre-apprenticeship project, a discussion of the teacher's role in conducting the course, and scope and content of the four phases of…

  15. Bricklaying. Pre-Apprenticeship Phase 2 Training. Instructor's Guide.

    ERIC Educational Resources Information Center

    Cholewinski, Scott

    This instructor's guide accompanies the self-paced student training modules on bricklaying available separately as CE 031 568. Introductory materials include a description of the components of the pre-apprenticeship project, discussion of teacher's role in students' completion of the modules, and scope and contents of Phase 2 training. Each of the…

  16. The Forest Inventory and Analysis Database Version 4.0: Database Description and Users Manual for Phase 3

    Treesearch

    Christopher W. Woodall; Barbara L. Conkling; Michael C. Amacher; John W. Coulston; Sarah Jovan; Charles H. Perry; Beth Schulz; Gretchen C. Smith; Susan Will Wolf

    2010-01-01

    Describes the structure of the Forest Inventory and Analysis Database (FIADB) 4.0 for phase 3 indicators. The FIADB structure provides a consistent framework for storing forest health monitoring data across all ownerships for the entire United States. These data are available to the public.

  17. Good Moments in Gestalt Therapy: A Descriptive Analysis of Two Perls Sessions.

    ERIC Educational Resources Information Center

    Boulet, Donald; And Others

    1993-01-01

    Analyzed two Gestalt therapy sessions conducted by Fritz Perls using category system for identifying in-session client behaviors valued by Gestalt therapists. Four judges independently rated 210 client statements. Found common pattern of therapeutic movement: initial phase dominated by building block good moments and second phase characterized by…

  18. Parts Counter. Pre-Apprenticeship Phase 2 Training. Instructor's Guide.

    ERIC Educational Resources Information Center

    Snyder, James A.

    This instructor's guide accompanies the self-paced student training modules on parts counter, available separately as CE 031 572. Introductory materials include a description of the components of the pre-apprenticeship project, discussion of teacher's role in students' completion of the modules, and scope and contents of Phase 2 training. Each of…

  19. From the Mountains to the Valleys: Theorizing Gender in Sport through McIntosh's Interactive Phases.

    ERIC Educational Resources Information Center

    Fairchild, David L.

    1994-01-01

    This paper uses Peggy McIntosh's (1983) interactive phase typology as a descriptive model within which to characterize contemporary sport with respect to certain gender issues, accepting gender as dynamically and culturally constituted. The paper discusses possibilities for transforming sport by enhancing the appreciation of sport and enriching…

  20. The Prevention of Teacher Burnout Through Stress Management.

    ERIC Educational Resources Information Center

    Matthews, Doris B.

    The physical and emotional manifestations of burnout are described. A five-phase model is outlined for preventing extensive stress leading to teacher burnout. Phase One is predicated upon the notion that a professional cannot manage stress without the ability to identify it. Descriptions are given of the signs of physiological, psychological, and…

  1. AAAS: Automated Affirmative Action System. General Description, Phase 1.

    ERIC Educational Resources Information Center

    Institute for Services to Education, Inc., Washington, DC. TACTICS Management Information Systems Directorate.

    This document describes phase 1 of the Automated Affirmative Action System (AAAS) of the Tuskegee Institute, which was designed to organize an inventory of any patterns of job classification and assignment identifiable by sex or minority group; any job classification or organizational unit where women and minorities are not employed or are…

  2. A Typology for Observing Children's Engagement with eBooks at Preschool

    ERIC Educational Resources Information Center

    Roskos, Kathleen; Burstein, Karen; You, Byeong-Keun

    2012-01-01

    This research reports a two-phase descriptive study of young children's engagement with ebooks conducted in Head Start classrooms. Phase 1 focused on the development of a typology as an analytic framework for observing engagement with ebooks in different formats (shared book; independent book browsing) and across devices (stationary touch screen;…

  3. Spectral weight of excitations in Bose Hubbard model

    NASA Astrophysics Data System (ADS)

    Alavani, Bhargav K.; Pai, Ramesh V.

    2017-05-01

    We obtain excitation spectra in the superfluid and the Mott Insulator phases of Bose Hubbard model near unit filling within Random Phase Approximation (RPA) and calculate its spectral weight. This gives a transparent description of contribution of each excitation towards the total Density of States (DOS) which we calculate from these spectral weights.

  4. Cement Finishing. Pre-Apprenticeship Phase 2 Training. Instructor's Guide.

    ERIC Educational Resources Information Center

    Nama, Joe

    This instructor's guide accompanies the self-paced student training modules on cement finishing, available separately as CE 031 576. Introductory materials include a description of the components of the pre-apprenticeship project, discussion of teacher's role in students' completion of the modules, and scope and contents of Phase 2 training. Each…

  5. Commercial Contract Training, Marine Corps Area VOTEC Support Center (AVSC) Guidelines. Final Report.

    ERIC Educational Resources Information Center

    Copeland, D. R.; And Others

    The report provides a description of the Phase II findings of a two-phase study to determine if certain Marine Corps skill training requirements could be satisfied through contract with qualified commercial sources. It demonstrates the utility of the commercial contract training concept and contains information useful to Area VOTEC…

  6. Beyond Sex: The Influence of Gender Perceptions on Hiring Decisions.

    ERIC Educational Resources Information Center

    Horn, Jennifer L.; Gaeddert, William P.

    Recently, the concept of gender has been introduced as a possible influence on hiring bias. To examine the relationship between gender perception and bias in hiring, a two-part study was conducted. In the initial phase, 99 college students developed descriptions of applicants that reflected gender characteristics. In the second phase, 63 college…

  7. Order in dense hydrogen at low temperatures

    PubMed Central

    Edwards, B.; Ashcroft, N. W.

    2004-01-01

    By increase in density, impelled by pressure, the electronic energy bands in dense hydrogen attain significant widths. Nevertheless, arguments can be advanced suggesting that a physically consistent description of the general consequences of this electronic structure can still be constructed from interacting but state-dependent multipoles. These reflect, in fact self-consistently, a disorder-induced localization of electron states partially manifesting the effects of proton dynamics; they retain very considerable spatial inhomogeneity (as they certainly do in the molecular limit). This description, which is valid provided that an overall energy gap has not closed, leads at a mean-field level to the expected quadrupolar coupling, but also for certain structures to the eventual emergence of dipolar terms and their coupling when a state of broken charge symmetry is developed. A simple Hamiltonian incorporating these basic features then leads to a high-density, low-temperature phase diagram that appears to be in substantial agreement with experiment. In particular, it accounts for the fact that whereas the phase I–II phase boundary has a significant isotope dependence, the phase II–III boundary has very little. PMID:15028839

  8. Communicating Experimental Findings in Single Case Design Research: How to Use Celeration Values and Celeration Multipliers to Measure Direction, Magnitude, and Change of Slope

    ERIC Educational Resources Information Center

    Datchuk, Shawn M.; Kubina, Richard M., Jr.

    2011-01-01

    The accumulation of scientific knowledge greatly depends upon the critical review of experimental findings by ones peers. In single case design research, experimenters present findings with graphical displays of data and narrative description of a visual analysis. To aid in efficient and accurate description of experimental findings, the research…

  9. Linear system theory

    NASA Technical Reports Server (NTRS)

    Callier, Frank M.; Desoer, Charles A.

    1991-01-01

    The aim of this book is to provide a systematic and rigorous access to the main topics of linear state-space system theory in both the continuous-time case and the discrete-time case; and the I/O description of linear systems. The main thrusts of the work are the analysis of system descriptions and derivations of their properties, LQ-optimal control, state feedback and state estimation, and MIMO unity-feedback systems.

  10. The WINCOF-I code: Detailed description

    NASA Technical Reports Server (NTRS)

    Murthy, S. N. B.; Mullican, A.

    1993-01-01

    The performance of an axial-flow fan-compressor unit is basically unsteady when there is ingestion of water along with the gas phase. The gas phase is a mixture of air and water vapor in the case of a bypass fan engine that provides thrust power to an aircraft. The liquid water may be in the form of droplets and film at entry to the fan. The unsteadiness is then associated with the relative motion between the gas phase and water, at entry and within the machine, while the water undergoes impact on material surfaces, centrifuging, heat and mass transfer processes, and reingestion in blade wakes, following peal off from blade surfaces. The unsteadiness may be caused by changes in atmospheric conditions and at entry into and exit from rain storms while the aircraft is in flight. In a multi-stage machine, with an uneven distribution of blade tip clearance, the combined effect of various processes in the presence of steady or time-dependent ingestion is such as to make the performance of a fan and a compressor unit time-dependent from the start of ingestion up to a short time following termination of ingestion. The original WINCOF code was developed without accounting for the relative motion between gas and liquid phases in the ingested fluid. A modification of the WINCOF code was developed and named WINCOF-1. The WINCOF-1 code can provide the transient performance of a fan-compressor unit under a variety of input conditions.

  11. Health care and social service professionals' perceptions of a home-visit program for young, first-time mothers.

    PubMed

    Li, S A; Jack, S M; Gonzalez, A; Duku, E; MacMillan, H L

    2015-01-01

    Little is known about health care and social service professionals' perspective on the acceptability of long-term home-visit programs serving low-income, first-time mothers. This study describes the experiences and perspectives of these community care providers involved with program referrals or service delivery to mothers who participated in the Nurse-Family Partnership (NFP), a targeted nurse home-visit program. The study included two phases. Phase I was a secondary qualitative data analysis used to analyze a purposeful sample of 24 individual interviews of community care providers. This was part of a larger case study examining adaptations required to increase acceptability of the NFP in Hamilton, Ontario, Canada. In Phase II (n = 4), themes identified from Phase I were further explored through individual, semi-structured interviews with community health care and social service providers, giving qualitative description. Overall, the NFP was viewed as addressing an important service gap for first-time mothers. Providers suggested that frequent communication between the NFP and community agencies serving these mothers could help improve the referral process, avoid service duplication, and streamline the flow of service access. The findings can help determine key components required to enhance the success of integrating a home-visit program into an existing network of community services. The function of home-visit programs should not be viewed in isolation. Rather, their potential can be maximized when they collaborate and share information with other agencies to provide better services for first-time mothers.

  12. General description of circularly symmetric Bessel beams of arbitrary order

    NASA Astrophysics Data System (ADS)

    Wang, Jia Jie; Wriedt, Thomas; Lock, James A.; Mädler, Lutz

    2016-11-01

    A general description of circularly symmetric Bessel beams of arbitrary order is derived in this paper. This is achieved by analyzing the relationship between different descriptions of polarized Bessel beams obtained using different approaches. It is shown that a class of circularly symmetric Davis Bessel beams derived using the Hertz vector potentials possesses the same general functional dependence as the aplanatic Bessel beams generated using the angular spectrum representation (ASR). This result bridges the gap between different descriptions of Bessel beams and leads to a general description of circularly symmetric Bessel beams, such that the Davis Bessel beams and the aplanatic Bessel beams are merely the two simplest cases of an infinite number of possible circularly symmetric Bessel beams. Additionally, magnitude profiles of the electric and magnetic fields, the energy density and the Poynting vector are displayed for Bessel beams in both paraxial and nonparaxial cases. The results presented in this paper provide a fresh perspective on the description of Bessel beams and cast some insights into the light scattering and light-matter interactions problems in practice.

  13. The Influence of Disease Severity of Preceding Clinical Cases on Pathologists' Medical Decision Making.

    PubMed

    Frederick, Paul D; Nelson, Heidi D; Carney, Patricia A; Brunyé, Tad T; Allison, Kimberly H; Weaver, Donald L; Elmore, Joann G

    2017-01-01

    Medical decision making may be influenced by contextual factors. We evaluated whether pathologists are influenced by disease severity of recently observed cases. Pathologists independently interpreted 60 breast biopsy specimens (one slide per case; 240 total cases in the study) in a prospective randomized observational study. Pathologists interpreted the same cases in 2 phases, separated by a washout period of >6 months. Participants were not informed that the cases were identical in each phase, and the sequence was reordered randomly for each pathologist and between phases. A consensus reference diagnosis was established for each case by 3 experienced breast pathologists. Ordered logit models examined the effect the pathologists' diagnoses on the preceding case or the 5 preceding cases had on their diagnosis for the subsequent index case. Among 152 pathologists, 49 provided interpretive data in both phases I and II, 66 from only phase I, and 37 from phase II only. In phase I, pathologists were more likely to indicate a more severe diagnosis than the reference diagnosis when the preceding case was diagnosed as ductal carcinoma in situ (DCIS) or invasive cancer (proportional odds ratio [POR], 1.28; 95% confidence interval [CI], 1.15-1.42). Results were similar when considering the preceding 5 cases and for the pathologists in phase II who interpreted the same cases in a different order compared with phase I (POR, 1.17; 95% CI, 1.05-1.31). Physicians appear to be influenced by the severity of previously interpreted test cases. Understanding types and sources of diagnostic bias may lead to improved assessment of accuracy and better patient care. © The Author(s) 2016.

  14. Interferometry theory for the block 2 processor

    NASA Technical Reports Server (NTRS)

    Thomas, J. B.

    1987-01-01

    Presented is the interferometry theory for the Block 2 processor, including a high-level functional description and a discussion of data structure. The analysis covers the major processing steps: cross-correlation, fringe counter-rotation, transformation to the frequency domain, phase calibration, bandwidth synthesis, and extraction of the observables of amplitude, phase, phase rate, and delay. Also included are analyses for fractional bitshift correction, station clock error, ionosphere correction, and effective frequencies for the observables.

  15. Dislocation Transport in Continuum Crystal Plasticity Simulations (First-year Report)

    DTIC Science & Technology

    2011-12-01

    plasticity model are taken from an existing implementation in ALE3D (Becker, 2004). A brief description is given below. An idealized, two...fluxes are determined on element faces during a first phase , and the deformation due to those fluxes is applied in the subsequent phase . This is...this first phase are averaged on the faces, giving values denoted as , where the superscript refers to the face number associated with the element

  16. Description of the last instar larva and new contributions to the knowledge of the pupa of Dasyhelea mediomunda Minaya (Diptera, Culicomorpha, Ceratopogonidae).

    PubMed

    Díaz, Florentina; Anjos-Santos, Danielle; Funes, Amparo; Ronderos, María M

    2016-01-01

    The fourth instar larva of Dasyhelea mediomunda Minaya is described for the first time and a complete description of the pupa is provided, through use of phase-contrast microscope and scanning electron microscope. Studied specimens were collected in a pond connected to a small wetland "mallin" on the Patagonian steppe, Chubut province, Argentina.

  17. Hypothenar hammer syndrome: a case and brief review.

    PubMed

    Swanson, Keith E; Bartholomew, John R; Paulson, Rolf

    2012-04-01

    Hypothenar hammer syndrome is an uncommon cause of upper-extremity ischemia that is often overlooked in the absence of a thorough occupational and recreational history. Importantly, it is a reversible cause of hand ischemia that, if missed, can lead to significant morbidity and even amputation. The occupational ramifications and quality of life of those affected can be significant. Its relative rarity, set against the ubiquitous use of the hand as a 'hammer' is noteworthy. Several other causes of hand ischemia can present similarly; therefore, consideration of other etiologies must be thoroughly investigated. Key distinguishing clinical features, in addition to a detailed occupational and recreational history, may include characteristic sparing of the thumb, the absence of a hyperemic phase in 'Raynaud's phenomenon', and a positive Allen's sign. Both non-invasive and invasive diagnostic studies, including bilateral upper-limb segmental pulse volume recordings (PVR), arterial duplex examination, and upper-extremity angiography, are complementary to a thorough history and physical examination. Optimal management strategies are not well defined because of its rarity and resultant lack of quality, evidence-based data. Though most cases can be successfully managed non-operatively, micrographic arterial reconstruction may be limb saving in severe or recalcitrant cases. Newer, experimental strategies including selective sympathetic blockage using botulinum toxin A have been reported in a few recalcitrant cases. The brief case description illustrates the typical presentation and potential treatment strategies employed in a difficult case. A review of relevant literature is also presented.

  18. Anharmonic quantum mechanical systems do not feature phase space trajectories

    NASA Astrophysics Data System (ADS)

    Oliva, Maxime; Kakofengitis, Dimitris; Steuernagel, Ole

    2018-07-01

    Phase space dynamics in classical mechanics is described by transport along trajectories. Anharmonic quantum mechanical systems do not allow for a trajectory-based description of their phase space dynamics. This invalidates some approaches to quantum phase space studies. We first demonstrate the absence of trajectories in general terms. We then give an explicit proof for all quantum phase space distributions with negative values: we show that the generation of coherences in anharmonic quantum mechanical systems is responsible for the occurrence of singularities in their phase space velocity fields, and vice versa. This explains numerical problems repeatedly reported in the literature, and provides deeper insight into the nature of quantum phase space dynamics.

  19. The phase diagrams of iron-based superconductors: Theory and experiments

    NASA Astrophysics Data System (ADS)

    Martinelli, Alberto; Bernardini, Fabio; Massidda, Sandro

    2016-01-01

    Phase diagrams play a primary role in the understanding of materials properties. For iron-based superconductors (Fe-SC), the correct definition of their phase diagrams is crucial because of the close interplay between their crystallochemical and magnetic properties, on one side, and the possible coexistence of magnetism and superconductivity, on the other. The two most difficult issues for understanding the Fe-SC phase diagrams are: 1) the origin of the structural transformation taking place during cooling and its relationship with magnetism; 2) the correct description of the region where a crossover between the magnetic and superconducting electronic ground states takes place. Hence a proper and accurate definition of the structural, magnetic and electronic phase boundaries provides an extremely powerful tool for material scientists. For this reason, an exact definition of the thermodynamic phase fields characterizing the different structural and physical properties involved is needed, although it is not easy to obtain in many cases. Moreover, physical properties can often be strongly dependent on the occurrence of micro-structural and other local-scale features (lattice micro-strain, chemical fluctuations, domain walls, grain boundaries, defects), which, as a rule, are not described in a structural phase diagram. In this review, we critically summarize the results for the most studied 11-, 122- and 1111-type compound systems, providing a correlation between experimental evidence and theory. Les deux difficultés principales pour la compréhension des diagrammes de phase Fe-SC sont : 1) l'origine de la transformation structurelle ayant lieu pendant le refroidissement et sa relation avec le magnétisme ; 2) la description correcte de la région où survient un recouvrement entre les états fondamentaux électroniques, magnétiques et supraconducteur électronique survient. De ce fait, une définition appropriée et précise des frontières des phases structurelle, magnétique et électronique fournit un outil extrêmement puissant pour les scientifiques du domaine des matériaux. Pour cette raison, une définition exacte des champs de phases thermodynamiques caractérisant les différentes propriétés structurelles et physiques impliquées est nécessaire, bien qu'elle ne soit pas aisée à obtenir dans de nombreux cas. De plus, les propriétés physiques peuvent souvent dépendre fortement de la survenue de caractéristiques micro-structurelles ou autres à l'échelle locale (micro-contraintes dans le réseau, fluctuations chimiques, parois de domaines, joints de grains, défauts), qui, d'ordinaire, ne sont pas décrites dans un diagramme de phases structurelles. Dans cette revue, nous résumons de manière critique les résultats obtenus pour les systèmes composites le plus étudiés de types 11, 122 et 1111, qui établissent une corrélation entre les preuves expérimentales et la théorie.

  20. Phenotypic Description of the Spanish Multicentre Genetic Glaucoma Group Cohort

    PubMed Central

    Gamundi, Maria José; Duch, Susana; Rios, Jose; Carballo, Miguel; Study Group, EMEIGG

    2017-01-01

    Introduction The aim of the study was to make a phenotypic description of the Spanish multicentre glaucoma group cohort of patients. Design Retrospective, observational, multicentre, cohort study. Material and Methods The clinical charts of 152 patients with hereditary glaucoma from18 Spanish eye centres were reviewed in order to make an epidemiologic description of the type of glaucoma and associated factors. True hereditary cases were compared with familiar cases according to the Gong et al. criteria. Results 61% were true hereditary cases and 39% familiar cases. Ocular comorbidity, optic disc damage, and visual field mean defect were significantly more severe in hereditary patients, who required significantly more first-line hypotensive drugs and surgical interventions to control intraocular pressure than familiar patients. Conclusions The strength of the hereditary component of glaucoma seems to worsen the clinical course, causing more structural and functional damage and requiring more intense glaucoma treatment. The family history of glaucoma should be carefully investigated and taken into consideration when making treatment decisions or intensifying previous treatment. PMID:29082038

  1. A digitally implemented phase-locked loop detection scheme for analysis of the phase and power stability of a calibration tone

    NASA Technical Reports Server (NTRS)

    Densmore, A. C.

    1988-01-01

    A digital phase-locked loop (PLL) scheme is described which detects the phase and power of a high SNR calibration tone. The digital PLL is implemented in software directly from the given description. It was used to evaluate the stability of the Goldstone Deep Space Station open loop receivers for Radio Science. Included is a derivative of the Allan variance sensitivity of the PLL imposed by additive white Gaussian noise; a lower limit is placed on the carrier frequency.

  2. Warm ''pasta'' phase in the Thomas-Fermi approximation

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

    Avancini, Sidney S.; Menezes, Debora P.; Chiacchiera, Silvia

    In the present article, the 'pasta' phase is studied at finite temperatures within a Thomas-Fermi (TF) approach. Relativistic mean-field models, both with constant and density-dependent couplings, are used to describe this frustrated system. We compare the present results with previous ones obtained within a phase-coexistence description and conclude that the TF approximation gives rise to a richer inner ''pasta'' phase structure and the homogeneous matter appears at higher densities. Finally, the transition density calculated within TF is compared with the results for this quantity obtained with other methods.

  3. Glassy phases and driven response of the phase-field-crystal model with random pinning.

    PubMed

    Granato, E; Ramos, J A P; Achim, C V; Lehikoinen, J; Ying, S C; Ala-Nissila, T; Elder, K R

    2011-09-01

    We study the structural correlations and the nonlinear response to a driving force of a two-dimensional phase-field-crystal model with random pinning. The model provides an effective continuous description of lattice systems in the presence of disordered external pinning centers, allowing for both elastic and plastic deformations. We find that the phase-field crystal with disorder assumes an amorphous glassy ground state, with only short-ranged positional and orientational correlations, even in the limit of weak disorder. Under increasing driving force, the pinned amorphous-glass phase evolves into a moving plastic-flow phase and then, finally, a moving smectic phase. The transverse response of the moving smectic phase shows a vanishing transverse critical force for increasing system sizes.

  4. A Comparison of Outcomes from Descriptive and Functional Analyses of Problem Behavior

    PubMed Central

    Thompson, Rachel H; Iwata, Brian A

    2007-01-01

    We compared results of descriptive and functional analyses of problem behavior for 12 participants whose descriptive data have been reported previously (Thompson & Iwata, 2001). Results indicated that in only 3 of the 12 cases was problem behavior maintained by the consequence observed most frequently during the descriptive analysis. Attention was the most common consequence for problem behavior during descriptive analyses for 8 of the 12 participants; however, maintenance of problem behavior by attention was evident for only 2 of these 8 participants. PMID:17624074

  5. Context retrieval and description benefits for recognition of unfamiliar faces.

    PubMed

    Jones, Todd C; Robinson, Kealagh; Steel, Brenna C

    2018-04-19

    Describing unfamiliar faces during or immediately after their presentation in a study phase can produce better recognition memory performance compared with a view-only control condition. We treated descriptions as elaborative information that is part of the study context and investigated how context retrieval influences recognition memory. Following general dual-process theories, we hypothesized that recollection would be used to recall descriptions and that description recall would influence recognition decisions, including the level of recognition confidence. In four experiments description conditions produced higher hit rates and higher levels of recognition confidence than control conditions. Participants recalled descriptive content on some trials, and this context retrieval was linked to an increase in the recognition confidence level. Repeating study faces in description conditions increased recognition scores, recognition confidence level, and context retrieval. Estimates of recollection from Yonelinas' (1994) dual-process signal detection ROCs were, on average, very close to the measures of context recall. Description conditions also produced higher estimates of familiarity. Finally, we found evidence that participants engaged in description activity in some ostensibly view-only trials. An emphasis on the information participants use in making their recognition decisions can advance understanding on description effects when descriptions are part of the study trial context. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  6. Weekly Time Course of Neuro-Muscular Adaptation to Intensive Strength Training.

    PubMed

    Brown, Niklas; Bubeck, Dieter; Haeufle, Daniel F B; Weickenmeier, Johannes; Kuhl, Ellen; Alt, Wilfried; Schmitt, Syn

    2017-01-01

    Detailed description of the time course of muscular adaptation is rarely found in literature. Thus, models of muscular adaptation are difficult to validate since no detailed data of adaptation are available. In this article, as an initial step toward a detailed description and analysis of muscular adaptation, we provide a case report of 8 weeks of intense strength training with two active, male participants. Muscular adaptations were analyzed on a morphological level with MRI scans of the right quadriceps muscle and the calculation of muscle volume, on a voluntary strength level by isometric voluntary contractions with doublet stimulation (interpolated twitch technique) and on a non-voluntary level by resting twitch torques. Further, training volume and isokinetic power were closely monitored during the training phase. Data were analyzed weekly for 1 week prior to training, pre-training, 8 weeks of training and 2 weeks of detraining (no strength training). Results show a very individual adaptation to the intense strength training protocol. While training volume and isokinetic power increased linearly during the training phase, resting twitch parameters decreased for both participants after the first week of training and stayed below baseline until de-training. Voluntary activation level showed an increase in the first 4 weeks of training, while maximum voluntary contraction showed only little increase compared to baseline. Muscle volume increased for both subjects. Especially training status seemed to influence the acute reaction to intense strength training. Fatigue had a major influence on performance and could only be overcome by one participant. The results give a first detailed insight into muscular adaptation to intense strength training on various levels, providing a basis of data for a validation of muscle fatigue and adaptation models.

  7. Luminescent MOFs comprising mixed tritopic linkers and Cd(II)/Zn(II) nodes for selective detection of organic nitro compounds and iodine capture

    NASA Astrophysics Data System (ADS)

    Rachuri, Yadagiri; Bisht, Kamal Kumar; Parmar, Bhavesh; Suresh, Eringathodi

    2015-03-01

    Two CPs {[Cd3(BTC)2(TIB)2(H2O)4].(H2O)2}n (1) and {[Zn3(BTC)2(TIB)2].(H2O)6}n (2) composed of tripodal linkers BTC (1,3,5-benzenetricarboxylate) and TIB (1,3,5-tris(imidazol-1-ylmethyl)benzene) were synthesized via solvothermal route and structurally characterized. Single crystal structural analysis reveals 1 possesses a novel 3D framework structure, whereas 2 represents a previously established compound. Owing to the d10 configuration of metal nodes and robust 3D frameworks, 1 and 2 exhibit excellent fluorescence properties which have been exploited to sense organic nitro compounds in vapor phase. Compound 1 demonstrates selective sensing of nitromethane over structurally similar methanol with ca. 70 and 43% fluorescence quenching in case of former and later. Similarly, 58% fluorescence quenching was observed in case of nitrobenzene over the structurally resembling toluene for which 30% quenching was observed. Compound 2 did not show any preference for nitro compounds and exhibited comparable fluorescence quenching when exposed to the vapors of nitro or other geometrically resembling organic molecules. Furthermore, adsorption experiments revealed that 1 and 2 can uptake 2.74 and 14.14 wt% molecular iodine respectively in vapor phase which can be released in organic solvents such as hexane and acetonitrile. The maximal iodine uptake in case of 1 and 2 corresponds to 0.15 and 0.80 molecules of iodine per formula unit of respective frameworks. Comprehensive structural description, thermal stability and luminescence behavior for both CPs has also been presented.

  8. GPS Receivers Use-Case Information : GPS Adjacent Band Compatibility Assessment Workshop

    DOT National Transportation Integrated Search

    2014-09-18

    Topics 1. Background. 2. Use Case Template. 3. Description of Submitted UseCases from DOT Extended Pos/Nav Working Group. 4. Utilization of UseCase Information. 5. Request of Information for Additional UseCases from GPS Receiver Manufacturer...

  9. What's in a Name? The Incorrect Use of Case Series as a Study Design Label in Studies Involving Dogs and Cats.

    PubMed

    Sargeant, J M; O'Connor, A M; Cullen, J N; Makielski, K M; Jones-Bitton, A

    2017-07-01

    Study design labels are used to identify relevant literature to address specific clinical and research questions and to aid in evaluating the evidentiary value of research. Evidence from the human healthcare literature indicates that the label "case series" may be used inconsistently and inappropriately. Our primary objective was to determine the proportion of studies in the canine and feline veterinary literature labeled as case series that actually corresponded to descriptive cohort studies, population-based cohort studies, or other study designs. Our secondary objective was to identify the proportion of case series in which potentially inappropriate inferential statements were made. Descriptive evaluation of published literature. One-hundred published studies (from 19 journals) labeled as case series. Studies were identified by a structured literature search, with random selection of 100 studies from the relevant citations. Two reviewers independently characterized each study, with disagreements resolved by consensus. Of the 100 studies, 16 were case series. The remaining studies were descriptive cohort studies (35), population-based cohort studies (36), or other observational or experimental study designs (13). Almost half (48.8%) of the case series or descriptive cohort studies, with no control group and no formal statistical analysis, included inferential statements about the efficacy of treatment or statistical significance of potential risk factors. Authors, peer-reviewers, and editors should carefully consider the design elements of a study to accurately identify and label the study design. Doing so will facilitate an understanding of the evidentiary value of the results. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  10. Comparative Analysis of the Relative Validity for Subjective Time Rating Scales. Final Report.

    ERIC Educational Resources Information Center

    Carpenter, James B.; And Others

    Since the accuracy and validity of occupational data may vary according to the rating scale format employed, the first phase of the research described in the report employed hypothetical job descriptions from which accurate criterion data could be generated. The second phase of the research required developing an occupational survey instrument…

  11. Social Indicators for Rural Development: Descriptive Social Reporting. Final Report, Sociology Report No. 141.

    ERIC Educational Resources Information Center

    Carter, Keith A.; And Others

    Project 2142 was a multi-phase effort to discover and mobilize for dissemination to rural decision-makers various information and findings pertaining to the quality of life experienced by rural people. The initial research phases involved design of a conceptual framework that placed some parameters on the variety of social phenomena studied.…

  12. Workplace Mathematics Research: Reflections on Personal Practical Experiences

    ERIC Educational Resources Information Center

    Naresh, Nirmala; Chahine, Iman

    2013-01-01

    This article describes our transitions through three phases of a reflective cycle as a journey from the past to the future. In the descriptive phase, we delve into our past research experiences and address questions such as: What is the role of mathematics at work? In doing so, we uncovered additional venues for exploration that called for a new…

  13. Development of an instrument measuring the perceived attributes of implementing a healthy diet innovation in the Lower Mississippi Delta

    USDA-ARS?s Scientific Manuscript database

    The purpose of this research was to develop a valid and reliable instrument to assess individuals' perceived attributes of implementing a healthy diet. Using the Diffusion of Innovations (DOI) theory as a conceptual framework, this descriptive study consisted of three phases. Phase 1 included group ...

  14. Reflections on the Status of Women Faculty: Part-Timers in Baccalaureate Nursing Programs.

    ERIC Educational Resources Information Center

    Hawkins, Joellen W.; And Others

    The use of part-time faculty in baccalaureate nursing programs and the views of part-timers about part-time employment were studies in two phases. The first phase was a descriptive exploration of the use of part-time faculty conducted in 1979 using questionnaires completed by administrative officers. Responses from administrators of 91…

  15. Evaluation of Vocational Technical Education. Phase II. A Skeletal Model with Suggested Research and Development Activities.

    ERIC Educational Resources Information Center

    New Educational Directions, Crawfordsville, IN.

    Phase 2 of this project presents a skeletal model for evaluating vocational education programs which can be applied to secondary, post-secondary, and adult education programs. The model addresses 13 main components of the vocational education system: descriptive information, demonstration of need, student recruitment and selection, curriculum,…

  16. An Approach to Using Toxicogenomic Data in US EPA Human ...

    EPA Pesticide Factsheets

    This draft report is a description of an approach to evaluate genomic data for use in risk assessment and a case study to illustrate the approach. The dibutyl phthalate (DBP) case study example focuses on male reproductive developmental effects and the qualitative application of the available genomic data. The case study presented in this draft document is a separate activity from any of the ongoing IRIS human health assessments for the phthalates. This draft report is a description of an approach to evaluate genomic data for use in risk assessment and a case study to illustrate the approach. The dibutyl phthalate (DBP) case study example focuses on male reproductive developmental effects and the qualitative application of the available genomic data.

  17. Sequencing sit-to-stand and upright posture for mobility limitation assessment: determination of the timing of the task phases from force platform data.

    PubMed

    Mazzà, Claudia; Zok, Mounir; Della Croce, Ugo

    2005-06-01

    The identification of quantitative tools to assess an individual's mobility limitation is a complex and challenging task. Several motor tasks have been designated as potential indicators of mobility limitation. In this study, a multiple motor task obtained by sequencing sit-to-stand and upright posture was used. Algorithms based on data obtained exclusively from a single force platform were developed to detect the timing of the motor task phases (sit-to-stand, preparation to the upright posture and upright posture). To test these algorithms, an experimental protocol inducing predictable changes in the acquired signals was designed. Twenty-two young, able-bodied subjects performed the task in four different conditions: self-selected natural and high speed with feet kept together, and self-selected natural and high speed with feet pelvis-width apart. The proposed algorithms effectively detected the timing of the task phases, the duration of which was sensitive to the four different experimental conditions. As expected, the duration of the sit-to-stand was sensitive to the speed of the task and not to the foot position, while the duration of the preparation to the upright posture was sensitive to foot position but not to speed. In addition to providing a simple and effective description of the execution of the motor task, the correct timing of the studied multiple task could facilitate the accurate determination of variables descriptive of the single isolated phases, allowing for a more thorough description of the motor task and therefore could contribute to the development of effective quantitative functional evaluation tests.

  18. Drive-induced delocalization in the Aubry-André model

    NASA Astrophysics Data System (ADS)

    Ray, S.; Ghosh, A.; Sinha, S.

    2018-01-01

    Motivated by the recent experiment by Bordia et al. [Nat. Phys. 13, 460 (2017), 10.1038/nphys4020], we study the single particle delocalization phenomena of the Aubry-André (AA) model subjected to periodic drives. In two distinct cases we construct an equivalent classical description to illustrate that the drive-induced delocalization phenomena stems from an instability and the onset of chaos in the underlying dynamics. In the first case we analyze the delocalization and the thermalization in a time modulated AA potential with respect to driving frequency and demonstrate that there exists a threshold value of the amplitude of the drive. In the next example, we show that the periodic modulation of the phase of the hopping amplitude induced by a gauge field leads to an unusual effect on delocalization with a nonmonotonic dependence on the driving frequency. Within a window of such a driving frequency a delocalized Floquet band with a mobility edge appears, exhibiting multifractality in the spectrum as well as in the Floquet eigenfunctions. Finally, we explore the effect of interaction and discuss how the results of the present analysis can be tested experimentally.

  19. A statistical method to estimate low-energy hadronic cross sections

    NASA Astrophysics Data System (ADS)

    Balassa, Gábor; Kovács, Péter; Wolf, György

    2018-02-01

    In this article we propose a model based on the Statistical Bootstrap approach to estimate the cross sections of different hadronic reactions up to a few GeV in c.m.s. energy. The method is based on the idea, when two particles collide a so-called fireball is formed, which after a short time period decays statistically into a specific final state. To calculate the probabilities we use a phase space description extended with quark combinatorial factors and the possibility of more than one fireball formation. In a few simple cases the probability of a specific final state can be calculated analytically, where we show that the model is able to reproduce the ratios of the considered cross sections. We also show that the model is able to describe proton-antiproton annihilation at rest. In the latter case we used a numerical method to calculate the more complicated final state probabilities. Additionally, we examined the formation of strange and charmed mesons as well, where we used existing data to fit the relevant model parameters.

  20. Entropy in bimolecular simulations: A comprehensive review of atomic fluctuations-based methods.

    PubMed

    Kassem, Summer; Ahmed, Marawan; El-Sheikh, Salah; Barakat, Khaled H

    2015-11-01

    Entropy of binding constitutes a major, and in many cases a detrimental, component of the binding affinity in biomolecular interactions. While the enthalpic part of the binding free energy is easier to calculate, estimating the entropy of binding is further more complicated. A precise evaluation of entropy requires a comprehensive exploration of the complete phase space of the interacting entities. As this task is extremely hard to accomplish in the context of conventional molecular simulations, calculating entropy has involved many approximations. Most of these golden standard methods focused on developing a reliable estimation of the conformational part of the entropy. Here, we review these methods with a particular emphasis on the different techniques that extract entropy from atomic fluctuations. The theoretical formalisms behind each method is explained highlighting its strengths as well as its limitations, followed by a description of a number of case studies for each method. We hope that this brief, yet comprehensive, review provides a useful tool to understand these methods and realize the practical issues that may arise in such calculations. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Generation of Stationary Non-Gaussian Time Histories with a Specified Cross-spectral Density

    DOE PAGES

    Smallwood, David O.

    1997-01-01

    The paper reviews several methods for the generation of stationary realizations of sampled time histories with non-Gaussian distributions and introduces a new method which can be used to control the cross-spectral density matrix and the probability density functions (pdfs) of the multiple input problem. Discussed first are two methods for the specialized case of matching the auto (power) spectrum, the skewness, and kurtosis using generalized shot noise and using polynomial functions. It is then shown that the skewness and kurtosis can also be controlled by the phase of a complex frequency domain description of the random process. The general casemore » of matching a target probability density function using a zero memory nonlinear (ZMNL) function is then covered. Next methods for generating vectors of random variables with a specified covariance matrix for a class of spherically invariant random vectors (SIRV) are discussed. Finally the general case of matching the cross-spectral density matrix of a vector of inputs with non-Gaussian marginal distributions is presented.« less

  2. Adaptation of a Motivational Interviewing Intervention to Improve Antidepressant Adherence among Latinos

    PubMed Central

    Interian, Alejandro; Martinez, Igda; Rios, Lisbeth Iglesias; Krejci, Jonathan; Guarnaccia, Peter J.

    2009-01-01

    Poor antidepressant adherence is a significant issue in depression treatment that adversely affects treatment outcomes. While being a common problem, it tends to be more common among Latinos. To address this problem, the current study adapted a Motivational Interviewing (MI) intervention to improve adherence among Latinos with depression. The adaptation process included six focus groups that elicited participants’ perspectives (N = 30), applying the intervention with test cases (N = 7) to fine tune the intervention, and eliciting feedback on the intervention (N = 5). The findings generated from these adaptation phases are described, along with a case example. Examples of adaptations to the MI included reframing antidepressant adherence as a way to luchar (struggle) against problems, focusing on motivation for improving depression and not just medication, refining methods for imparting antidepressant information, and inclusion of personalized visual feedback on dose-taking. The findings provide a description of the antidepressant issues experienced by a group of Latinos, as well as considerations for applying MI with this population. The intervention remained grounded in MI principles, but was contextualized for this Latino group. PMID:20438160

  3. The modeler's influence on calculated solubilities for performance assessments at the Aspo Hard-rock Laboratory

    USGS Publications Warehouse

    Ernren, A.T.; Arthur, R.; Glynn, P.D.; McMurry, J.

    1999-01-01

    Four researchers were asked to provide independent modeled estimates of the solubility of a radionuclide solid phase, specifically Pu(OH)4, under five specified sets of conditions. The objectives of the study were to assess the variability in the results obtained and to determine the primary causes for this variability.In the exercise, modelers were supplied with the composition, pH and redox properties of the water and with a description of the mineralogy of the surrounding fracture system A standard thermodynamic data base was provided to all modelers. Each modeler was encouraged to use other data bases in addition to the standard data base and to try different approaches to solving the problem.In all, about fifty approaches were used, some of which included a large number of solubility calculations. For each of the five test cases, the calculated solubilities from different approaches covered several orders of magnitude. The variability resulting from the use of different thermodynamic data bases was in most cases, far smaller than that resulting from the use of different approaches to solving the problem.

  4. New approach to effective diffusion coefficient evaluation in the nanostructured two-phase media

    NASA Astrophysics Data System (ADS)

    Lyashenko, Yu. O.; Liashenko, O. Y.; Morozovich, V. V.

    2018-03-01

    Most widely used basic and combined models for evaluation of the effective diffusion parameters of inhomogeneous two-phase zone are reviewed. A new combined model of effective medium is analyzed for the description of diffusion processes in the two-phase zones. In this model the effective diffusivity depends on the growth kinetic coefficients of each phase, the volume fractions of phases and on the additional parameter that generally characterizes the structure type of the two-phase zone. Our combined model describes two-phase zone evolution in the binary systems based on consideration of the diffusion fluxes through both phases. The Lattice Monte Carlo method was used to test the validity of different phenomenological models for evaluation of the effective diffusivity in nanostructured two-phase zones with different structural morphology.

  5. Mathematical modeling heat and mass transfer processes in porous media

    NASA Astrophysics Data System (ADS)

    Akhmed-Zaki, Darkhan

    2013-11-01

    On late development stages of oil-fields appears a complex problem of oil-recovery reduction. One of solution approaches is injecting of surfactant together with water in the form of active impurities into the productive layer - for decreasing oil viscosity and capillary forces between ``oil-water'' phases system. In fluids flow the surfactant can be in three states: dissolved in water, dissolved in oil and adsorbed on pore channels' walls. The surfactant's invasion into the reservoir is tracked by its diffusion with reservoir liquid and mass-exchange with two phase (liquid and solid) components of porous structure. Additionally, in this case heat exchange between fluids (injected, residual) and framework of porous medium has practical importance for evaluating of temperature influences on enhancing oil recovery. Now, the problem of designing an adequate mathematical model for describing a simultaneous flowing heat and mass transfer processes in anisotropic heterogeneous porous medium -surfactant injection during at various temperature regimes has not been fully researched. In this work is presents a 2D mathematical model of surfactant injections into the oil reservoir. Description of heat- and mass transfer processes in a porous media is done through differential and kinetic equations. For designing a computational algorithm is used modify version of IMPES method. The sequential and parallel computational algorithms are developed using an adaptive curvilinear meshes which into account heterogeneous porous structures. In this case we can evaluate the boundaries of our process flows - fronts (``invasion'', ``heat'' and ``mass'' transfers), according to the pressure, temperature, and concentration gradient changes.

  6. Yang-Mills correlators across the deconfinement phase transition

    NASA Astrophysics Data System (ADS)

    Reinosa, U.; Serreau, J.; Tissier, M.; Tresmontant, A.

    2017-02-01

    We compute the finite temperature ghost and gluon propagators of Yang-Mills theory in the Landau-DeWitt gauge. The background field that enters the definition of the latter is intimately related with the (gauge-invariant) Polyakov loop and serves as an equivalent order parameter for the deconfinement transition. We use an effective gauge-fixed description where the nonperturbative infrared dynamics of the theory is parametrized by a gluon mass which, as argued elsewhere, may originate from the Gribov ambiguity. In this scheme, one can perform consistent perturbative calculations down to infrared momenta, which have been shown to correctly describe the phase diagram of Yang-Mills theories in four dimensions as well as the zero-temperature correlators computed in lattice simulations. In this article, we provide the one-loop expressions of the finite temperature Landau-DeWitt ghost and gluon propagators for a large class of gauge groups and present explicit results for the SU(2) case. These are substantially different from those previously obtained in the Landau gauge, which corresponds to a vanishing background field. The nonanalyticity of the order parameter across the transition is directly imprinted onto the propagators in the various color modes. In the SU(2) case, this leads, for instance, to a cusp in the electric and magnetic gluon susceptibilities as well as similar signatures in the ghost sector. We mention the possibility that such distinctive features of the transition could be measured in lattice simulations in the background field gauge studied here.

  7. Phase and amplitude wave front sensing and reconstruction with a modified plenoptic camera

    NASA Astrophysics Data System (ADS)

    Wu, Chensheng; Ko, Jonathan; Nelson, William; Davis, Christopher C.

    2014-10-01

    A plenoptic camera is a camera that can retrieve the direction and intensity distribution of light rays collected by the camera and allows for multiple reconstruction functions such as: refocusing at a different depth, and for 3D microscopy. Its principle is to add a micro-lens array to a traditional high-resolution camera to form a semi-camera array that preserves redundant intensity distributions of the light field and facilitates back-tracing of rays through geometric knowledge of its optical components. Though designed to process incoherent images, we found that the plenoptic camera shows high potential in solving coherent illumination cases such as sensing both the amplitude and phase information of a distorted laser beam. Based on our earlier introduction of a prototype modified plenoptic camera, we have developed the complete algorithm to reconstruct the wavefront of the incident light field. In this paper the algorithm and experimental results will be demonstrated, and an improved version of this modified plenoptic camera will be discussed. As a result, our modified plenoptic camera can serve as an advanced wavefront sensor compared with traditional Shack- Hartmann sensors in handling complicated cases such as coherent illumination in strong turbulence where interference and discontinuity of wavefronts is common. Especially in wave propagation through atmospheric turbulence, this camera should provide a much more precise description of the light field, which would guide systems in adaptive optics to make intelligent analysis and corrections.

  8. Simulation of semi-explicit mechanisms of SOA formation from glyoxal in a 3D model

    NASA Astrophysics Data System (ADS)

    Knote, C. J.; Hodzic, A.; Jimenez, J. L.; Volkamer, R.; Orlando, J. J.; Baidar, S.; Brioude, J. F.; Fast, J. D.; Gentner, D. R.; Goldstein, A. H.; Hayes, P. L.; Knighton, W. B.; Oetjen, H.; Setyan, A.; Stark, H.; Thalman, R. M.; Tyndall, G. S.; Washenfelder, R. A.; Waxman, E.; Zhang, Q.

    2013-12-01

    Formation of secondary organic aerosols (SOA) through multi-phase processing of glyoxal has been proposed recently as a relevant contributor to SOA mass. Glyoxal has both anthropogenic and biogenic sources, and readily partitions into the aqueous-phase of cloud droplets and aerosols. Both reversible and irreversible chemistry in the liquid-phase has been observed. A recent laboratory study indicates that the presence of salts in the liquid-phase strongly enhances the Henry';s law constant of glyoxal, allowing for much more effective multi-phase processing. In our work we investigate the contribution of glyoxal to SOA formation on the regional scale. We employ the regional chemistry transport model WRF-chem with MOZART gas-phase chemistry and MOSAIC aerosols, which we both extended to improve the description of glyoxal formation in the gas-phase, and its interactions with aerosols. The detailed description of aerosols in our setup allows us to compare very simple (uptake coefficient) parameterizations of SOA formation from glyoxal, as has been used in previous modeling studies, with much more detailed descriptions of the various pathways postulated based on laboratory studies. Measurements taken during the CARES and CalNex campaigns in California in summer 2010 allowed us to constrain the model, including the major direct precursors of glyoxal. Simulations at convection-permitting resolution over a 2 week period in June 2010 have been conducted to assess the effect of the different ways to parameterize SOA formation from glyoxal and investigate its regional variability. We find that depending on the parameterization used the contribution of glyoxal to SOA is between 1 and 15% in the LA basin during this period, and that simple parameterizations based on uptake coefficients derived from box model studies lead to higher contributions (15%) than parameterizations based on lab experiments (1%). A kinetic limitation found in experiments hinders substantial contribution of volume-based pathways to total SOA formation from glyoxal. Once removed, 5% of total SOA can be formed from glyoxal through these channels. Results from a year-long simulation over the continental US will give a broader picture of the contribution of glyoxal to SOA formation.

  9. INTEGRATED PROTECTIVE FABRIC SYSTEM (IPFS) PHASE III PROGRAM: AEROSOL PROTECTION REPORT

    DTIC Science & Technology

    2017-08-16

    one layer control. It was observed that aerosol swatch measurements showed no correlation to aerosol system test performance for the materials and...the BRHA model employed. It was observed that aerosol swatch measurements showed no correlation to aerosol system test performance for the...Testing” (McVeety et al., 2015). This report includes a description of the materials and material controls, a description of the IPFS configurations

  10. Developing the DESCARTE Model: The Design of Case Study Research in Health Care.

    PubMed

    Carolan, Clare M; Forbat, Liz; Smith, Annetta

    2016-04-01

    Case study is a long-established research tradition which predates the recent surge in mixed-methods research. Although a myriad of nuanced definitions of case study exist, seminal case study authors agree that the use of multiple data sources typify this research approach. The expansive case study literature demonstrates a lack of clarity and guidance in designing and reporting this approach to research. Informed by two reviews of the current health care literature, we posit that methodological description in case studies principally focuses on description of case study typology, which impedes the construction of methodologically clear and rigorous case studies. We draw from the case study and mixed-methods literature to develop the DESCARTE model as an innovative approach to the design, conduct, and reporting of case studies in health care. We examine how case study fits within the overall enterprise of qualitatively driven mixed-methods research, and the potential strengths of the model are considered. © The Author(s) 2015.

  11. The generalised isodamping approach for robust fractional PID controllers design

    NASA Astrophysics Data System (ADS)

    Beschi, M.; Padula, F.; Visioli, A.

    2017-06-01

    In this paper, we present a novel methodology to design fractional-order proportional-integral-derivative controllers. Based on the description of the controlled system by means of a family of linear models parameterised with respect to a free variable that describes the real process operating point, we design the controller by solving a constrained min-max optimisation problem where the maximum sensitivity has to be minimised. Among the imposed constraints, the most important one is the new generalised isodamping condition, that defines the invariancy of the phase margin with respect to the free parameter variations. It is also shown that the well-known classical isodamping condition is a special case of the new technique proposed in this paper. Simulation results show the effectiveness of the proposed technique and the superiority of the fractional-order controller compared to its integer counterpart.

  12. Hydrodynamics and Heat Transfer in the Case of Combined Flow in a Annular Channel of Small Cross Section

    NASA Astrophysics Data System (ADS)

    Komov, A. T.; Varava, A. N.; Dedov, A. V.; Zakharenkov, A. V.; Boltenko, É. A.

    2017-01-01

    The present work is a continuation of experimental investigations conducted at the Moscow Power Engineering Institute (MPEI) on heat-transfer intensification. Brief descriptions of the working section and structure of intensifiers are given and their basic geometric parameters are enumerated. New systematized experimental data on the coefficients of hydraulic resistance and heat transfer in the regime of single-phase convection are given in an extended range of regime parameters and geometric characteristics of the intensifiers. Considerable increase in the heat-transfer coefficient as a function of the geometric characteristics of the intensifier has been established experimentally. The values of the relative fin height, at which these are the maxima of heat transfer and hydraulic resistance, have been established. Calculated dependences for the coefficient of hydraulic resistance and heat transfer have been obtained.

  13. Establishing an academic neurology specialty program: experiences over a five-year period.

    PubMed

    Packer, Rebecca A; Lambrechts, Nicolaas E; Bentley, R Timothy

    2012-01-01

    Veterinary neurology is an expanding specialty field. At the time of this writing, 13 out of 33 (40%) US and Canadian veterinary colleges, and many more veterinary colleges outside of North America, had no active clinical neurology service. New academic programs will likely be established to fill this need, often starting with a single neurologist. Establishing a neurology service with one founding faculty member can be accomplished by developing the program in phases and creating a support network that optimizes faculty strengths and interests. Such an approach allows for the gradual expansion of services and staffing in a manageable way to ultimately provide a full-service program. A description of this development process at Purdue University School of Veterinary Medicine is presented as a case study and model for the establishment of other neurology or specialty services.

  14. Optimal use of human and machine resources for Space Station assembly operations

    NASA Technical Reports Server (NTRS)

    Parrish, Joseph C.

    1988-01-01

    This paper investigates the issues involved in determining the best mix of human and machine resources for assembly of the Space Station. It presents the current Station assembly sequence, along with descriptions of the available assembly resources. A number of methodologies for optimizing the human/machine tradeoff problem have been developed, but the Space Station assembly offers some unique issues that have not yet been addressed. These include a strong constraint on available EVA time for early flights and a phased deployment of assembly resources over time. A methodology for incorporating the previously developed decision methods to the special case of the Space Station is presented. This methodology emphasizes an application of multiple qualitative and quantitative techniques, including simulation and decision analysis, for producing an objective, robust solution to the tradeoff problem.

  15. Gas-phase geometry optimization of biological molecules as a reasonable alternative to a continuum environment description: fact, myth, or fiction?

    PubMed

    Sousa, Sérgio Filipe; Fernandes, Pedro Alexandrino; Ramos, Maria João

    2009-12-31

    Gas-phase optimization of single biological molecules and of small active-site biological models has become a standard approach in first principles computational enzymology. The important role played by the surrounding environment (solvent, enzyme, both) is normally only accounted for through higher-level single point energy calculations performed using a polarizable continuum model (PCM) and an appropriate dielectric constant with the gas-phase-optimized geometries. In this study we analyze this widely used approximation, by comparing gas-phase-optimized geometries with geometries optimized with different PCM approaches (and considering different dielectric constants) for a representative data set of 20 very important biological molecules--the 20 natural amino acids. A total of 323 chemical bonds and 469 angles present in standard amino acid residues were evaluated. The results show that the use of gas-phase-optimized geometries can in fact be quite a reasonable alternative to the use of the more computationally intensive continuum optimizations, providing a good description of bond lengths and angles for typical biological molecules, even for charged amino acids, such as Asp, Glu, Lys, and Arg. This approximation is particularly successful if the protonation state of the biological molecule could be reasonably described in vacuum, a requirement that was already necessary in first principles computational enzymology.

  16. Modelling the structure of Zr-rich Pb(Zr1-xTix)O3, x = 0.4 by a multiphase approach.

    PubMed

    Bogdanov, Alexander; Mysovsky, Andrey; Pickard, Chris J; Kimmel, Anna V

    2016-10-12

    Solid solution perovskite Pb(Zr 1-x Ti x )O 3 (PZT) is an industrially important material. Despite the long history of experimental and theoretical studies, the structure of this material is still under intensive discussion. In this work, we have applied structure searching coupled with density functional theory methods to provide a multiphase description of this material at x = 0.4. We demonstrate that the permutational freedom of B-site cations leads to the stabilisation of a variety of local phases reflecting a relatively flat energy landscape of PZT. Using a set of predicted local phases we reproduce the experimental pair distribution function (PDF) profile with high accuracy. We introduce a complex multiphase picture of the structure of PZT and show that additional monoclinic and rhombohedral phases account for a better description of the experimental PDF profile. We propose that such a multiphase picture reflects the entropy reached in the sample during the preparation process.

  17. Teaching and Learning in Two iPad-Infused Classrooms: A Descriptive Case Study of A Dual Classroom, School-Based Pilot Project

    ERIC Educational Resources Information Center

    Maich, Kimberly; Hall, Carmen L.; van Rhijn, Tricia Marie; Henning, Megan

    2017-01-01

    This multi-methods, descriptive case study examines attitudes and practices of classroom-based iPad use. The site is one inner-city, urban, publicly funded school, focused on two iPad-infused classrooms (Grade 2/3 and Grade 4/5). Data were collected from 5 educators and 35 students to investigate two research questions: How are iPads being…

  18. Dynamical Vertex Approximation for the Hubbard Model

    NASA Astrophysics Data System (ADS)

    Toschi, Alessandro

    A full understanding of correlated electron systems in the physically relevant situations of three and two dimensions represents a challenge for the contemporary condensed matter theory. However, in the last years considerable progress has been achieved by means of increasingly more powerful quantum many-body algorithms, applied to the basic model for correlated electrons, the Hubbard Hamiltonian. Here, I will review the physics emerging from studies performed with the dynamical vertex approximation, which includes diagrammatic corrections to the local description of the dynamical mean field theory (DMFT). In particular, I will first discuss the phase diagram in three dimensions with a special focus on the commensurate and incommensurate magnetic phases, their (quantum) critical properties, and the impact of fluctuations on electronic lifetimes and spectral functions. In two dimensions, the effects of non-local fluctuations beyond DMFT grow enormously, determining the appearance of a low-temperature insulating behavior for all values of the interaction in the unfrustrated model: Here the prototypical features of the Mott-Hubbard metal-insulator transition, as well as the existence of magnetically ordered phases, are completely overwhelmed by antiferromagnetic fluctuations of exponentially large extension, in accordance with the Mermin-Wagner theorem. Eventually, by a fluctuation diagnostics analysis of cluster DMFT self-energies, the same magnetic fluctuations are identified as responsible for the pseudogap regime in the holed-doped frustrated case, with important implications for the theoretical modeling of the cuprate physics.

  19. Diagnostic, design and implementation of an integrated model of care in France: a bottom-up process with a continuous leadership

    PubMed Central

    de Stampa, Matthieu; Vedel, Isabelle; Mauriat, Claire; Bagaragaza, Emmanuel; Routelous, Christelle; Bergman, Howard; Lapointe, Liette; Cassou, Bernard; Ankri, Joel; Henrard, Jean-Claude

    2010-01-01

    Purpose To present an innovative bottom-up and pragmatic strategy used to implement a new integrated care model in France for community-dwelling elderly people with complex needs. Context Sustaining integrated care is difficult, in large part because of problems encountered securing the participation of health care and social service professionals and, in particular, general practitioners (GPs). Case description In the first step, a diagnostic study was conducted with face-to-face interviews to gather data on current practices from a sample of health and social stakeholders working with elderly people. In the second step, an integrated care model called Coordination Personnes Agées (COPA) was designed by the same major stakeholders in order to define its detailed characteristics based on the local context. In the third step, the model was implemented in two phases: adoption and maintenance. This strategy was carried out by a continuous and flexible leadership throughout the process, initially with a mixed leadership (clinician and researcher) followed by a double one (clinician and managers of services) in the implementation phase. Conclusions The implementation of this bottom-up and pragmatic strategy relied on establishing a collaborative dynamic among health and social stakeholders. This enhanced their involvement throughout the implementation phase, particularly among the GPs, and allowed them to support the change practices and services arrangements.

  20. Crystal growth within a phase change memory cell.

    PubMed

    Sebastian, Abu; Le Gallo, Manuel; Krebs, Daniel

    2014-07-07

    In spite of the prominent role played by phase change materials in information technology, a detailed understanding of the central property of such materials, namely the phase change mechanism, is still lacking mostly because of difficulties associated with experimental measurements. Here, we measure the crystal growth velocity of a phase change material at both the nanometre length and the nanosecond timescale using phase-change memory cells. The material is studied in the technologically relevant melt-quenched phase and directly in the environment in which the phase change material is going to be used in the application. We present a consistent description of the temperature dependence of the crystal growth velocity in the glass and the super-cooled liquid up to the melting temperature.

  1. Deterministic quantum controlled-PHASE gates based on non-Markovian environments

    NASA Astrophysics Data System (ADS)

    Zhang, Rui; Chen, Tian; Wang, Xiang-Bin

    2017-12-01

    We study the realization of the quantum controlled-PHASE gate in an atom-cavity system beyond the Markovian approximation. The general description of the dynamics for the atom-cavity system without any approximation is presented. When the spectral density of the reservoir has the Lorentz form, by making use of the memory backflow from the reservoir, we can always construct the deterministic quantum controlled-PHASE gate between a photon and an atom, no matter the atom-cavity coupling strength is weak or strong. While, the phase shift in the output pulse hinders the implementation of quantum controlled-PHASE gates in the sub-Ohmic, Ohmic or super-Ohmic reservoirs.

  2. Conjunctivitis induced by a red bodied mite, Neotrombicula autumnalis

    PubMed Central

    Parcell, Benjamin J.; Sharpe, Graeme; Jones, Brian; Alexander, Claire L.

    2013-01-01

    This is a description of an unusual case of conjunctivitis caused by a trombiculid red mite, Neotrombicula autumnalis. The patient’s condition improved only after its removal and with application of carbomer gel eye drops. There have been reports of increasing numbers of severe cases of trombiculosis over the last 15 years particularly in Germany and a number of cases have also been reported in the United Kingdom. Cases where trombiculid larvae feed on any region of the head or face of humans are unknown. In addition it is most likely the patient acquired the infection from her pet cat and this is the first description of acquisition from this animal. PMID:23823162

  3. Edgar Allan Poe: a case description of the Marfan syndrome in an obscure short story.

    PubMed

    Battle, Robert W

    2011-07-01

    In the obscure short story “A Tale of the Ragged Mountains,” Edgar Allen Poe meticulously described a character with features remarkably consistent with the Marfan syndrome. This description appeared in fiction >50 years before the celebrated index description in the published medical research by Professor Antoine Marfan in Paris in 1896.

  4. Characterization of B-H agostic compounds involved in the dehydrogenation of amine-boranes by group 4 metallocenes.

    PubMed

    Zhu, Jingwen; Zins, Emilie-Laure; Alikhani, Mohammad Esmaïl

    2016-12-01

    For over a decade, amine-borane has been considered as a potential chemical hydrogen vector in the context of a search for cleaner energy sources. When catalyzed by organometallic complexes, the reaction mechanisms currently considered involve the formation of β-BH agostic intermediates. A thorough understanding of these intermediates may constitute a crucial step toward the identification of ideal catalysts. Topological approaches such as QTAIM and ELF revealed to be particularly suitable for the description of β-agostic interactions. When studying model catalysts, accurate theoretical calculations may be carried out. However, for a comparison with experimental data, calculations should also be carried out on large organo-metallic species, often including transition metals belonging to the second or the third row. In such a case, DFT methods are particularly attractive. Unfortunately, triple-ζ all electrons basis sets are not easily available for heavy transition metal elements. Thus, a subtle balance should be reached between the affordable level of calculations and the required accuracy of the electronic description of the systems. Herein we propose the use of B3LYP functional in combination with the LanL2DZ pseudopotential for the metal atom and 6-311++G(2d,2p) basis set for the other atoms, followed by a single point using the DKH2 relativistic Hamiltonian in combination with the B3LYP/DZP-DKH level, as a "minimum level of theory" leading to a consistent topological description of the interaction within the ELF and QTAIM framework, in the context of isolated (gas-phase) group 4 metallocene catalysts.

  5. Towards system-wide implementation of the International Classification of Functioning, Disability and Health (ICF) in routine practice: Developing simple, intuitive descriptions of ICF categories in the ICF Generic and Rehabilitation Set.

    PubMed

    Prodinger, Birgit; Reinhardt, Jan D; Selb, Melissa; Stucki, Gerold; Yan, Tiebin; Zhang, Xia; Li, Jianan

    2016-06-13

    A national, multi-phase, consensus process to develop simple, intuitive descriptions of International Classification of Functioning, Disability and Health (ICF) categories contained in the ICF Generic and Rehabilitation Sets, with the aim of enhancing the utility of the ICF in routine clinical practice, is presented in this study. A multi-stage, national, consensus process was conducted. The consensus process involved 3 expert groups and consisted of a preparatory phase, a consensus conference with consecutive working groups and 3 voting rounds (votes A, B and C), followed by an implementation phase. In the consensus conference, participants first voted on whether they agreed that an initially developed proposal for simple, intuitive descriptions of an ICF category was in fact simple and intuitive. The consensus conference was held in August 2014 in mainland China. Twenty-one people with a background in physical medicine and rehabilitation participated in the consensus process. Four ICF categories achieved consensus in vote A, 16 in vote B, and 8 in vote C. This process can be seen as part of a larger effort towards the system-wide implementation of the ICF in routine clinical and rehabilitation practice to allow for the regular and comprehensive evaluation of health outcomes most relevant for the monitoring of quality of care.

  6. PRINCEPS: A computer-based approach to the structural description and recognition of trends within structural databases, and its application to the Ce-Ni-Si System

    DOE PAGES

    Guo, Yiming; Fredrickson, Daniel C.

    2016-04-01

    Intermetallic crystal structures offer an enormous structural diversity, with an endless array of structural motifs whose connection to stability and physical properties are often mysterious. Making sense of the often complex crystal structures that arise here, developing a clear structural description, and identifying connections to other phases can be laborious and require an encyclopedic knowledge of structure types. In this Article, we present PRINCEPS, an algorithm based on a new coordination environment projection scheme that facilitates the structural analysis and comparison of such crystal structures. We demonstrate the potential of this approach by applying it to the complex Ce-Ni-Si ternarymore » system, whose 17 binary and 21 ternary phases would present a daunting challenge to one seeking to understand the system by manual inspection (but has nonetheless been well-described through the heroic efforts of previous researchers). With the help of PRINCEPS, most of the ternary phases in this system can be rationalized as intergrowths of simple structural fragments, and grouped into a handful of structural series (with some outliers). Lastly, these results illustrate how the PRINCEPS approach can be used to organize a vast collection of crystal structures into structurally meaningful families, and guide the description of complex atomic arrangements.« less

  7. Dengue fever in Czech travellers: A 10-year retrospective study in a tertiary care centre.

    PubMed

    Trojánek, Milan; Maixner, Jan; Sojková, Naděžda; Kynčl, Jan; Roháčová, Hana; Marešová, Vilma; Stejskal, František

    2016-01-01

    Dengue fever is a frequent cause of morbidity in travellers. The objective was to describe the epidemiological and clinical characteristics of dengue fever in Czech travellers. This descriptive study includes patients with acute dengue fever diagnosed at Hospital Na Bulovce during 2004-2013. Data were collected and analysed retrospectively. A total of 132 patients (83 males and 49 females) of median age 33 years (IQR 29-40) were included. Diagnosis was established by NS1 antigen detection in 87/107 cases (81.3%) and/or RT-PCR in 50/72 (69.4%) and by serology in 25 cases (18.9%). Dengue was acquired in South-East Asia in 69 cases (52.3%), followed by South Asia (48 cases; 36.3%), Latin America (14; 10.6%) and Sub-Saharan Africa (1; 0.8%). The most frequent symptoms included fever, rash and headache. Initial leukocyte and lymphocyte counts were lower in patients who presented in the early phase (0-4 days), however, platelet count was lower and AST, ALT and LDH activity higher in patients with a longer symptoms duration (≥5 days). The clinical course was mostly uncomplicated. Dengue fever is becoming a frequent cause of fever in Czech travellers. Clinicians should be familiar with the typical clinical findings and novel diagnostic methods. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Trial Courts - Alaska Court System

    Science.gov Websites

    Search Court Cases Search Case Information Through the CourtView Public Access Website Court Calendars & Case Dispositions Description Adult Change of Name Cases Filed * Lists adult change of name cases filed in the prior month Adult Change of Name Cases Granted * Lists adult change of name cases granted

  9. Phases of match-play in professional Australian Football: Descriptive analysis and reliability assessment.

    PubMed

    Rennie, Michael J; Watsford, Mark L; Spurrs, Robert W; Kelly, Stephen J; Pine, Matthew J

    2018-06-01

    To examine the frequency and time spent in the phases of Australian Football (AF) match-play and to assess the intra-assessor reliability of coding these phases of match-play. Observational, intra-reliability assessment. Video footage of 10 random quarters of AF match-play were coded by a single researcher. Phases of offence, defence, contested play, umpire stoppage, set shot and goal reset were coded using a set of operational definitions. Descriptive statistics were provided for all phases of match-play. Following a 6-month washout period, intra-coder reliability was assessed using typical error of measurement (TEM) and intra-class correlation coefficients (ICC). A quarter of AF match-play involved 128±20 different phases of match-play. The highest proportion of match-play involved contested play (25%), followed by offence (18%), defence (18%) and umpire stoppages (18%). The mean duration of offence, defence, contested play, umpire stoppage, set shot and goal reset were 14, 14, 10, 11, 28 and 47s, respectively. No differences were found between the two coding assessments (p>0.05). ICCs for coding the phases of play demonstrated very high reliability (r=0.902-0.992). TEM of the total time spent in each phase of play represented moderate to good reliability (TEM=1.8-9.3%). Coding of offence, defence and contested play tended to display slightly poorer TEMs than umpire stoppages, set shots and goal resets (TEM=8.1 vs 4.5%). Researchers can reliably code the phases of AF match-play which may permit the analysis of specific elements of competition. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  10. Environmental Technology Verification (ETV) Program Case Studies: Demonstrating Program Outcomes, Volume III

    EPA Science Inventory

    This booklet, ETV Program Case Studies: Demonstrating Program Outcomes, Volume III contains two case studies, addressing verified environmental technologies for decentalized wastewater treatment and converting animal waste to energy. Each case study contains a brief description ...

  11. Stochastic modelling of microstructure formation in solidification processes

    NASA Astrophysics Data System (ADS)

    Nastac, Laurentiu; Stefanescu, Doru M.

    1997-07-01

    To relax many of the assumptions used in continuum approaches, a general stochastic model has been developed. The stochastic model can be used not only for an accurate description of the fraction of solid evolution, and therefore accurate cooling curves, but also for simulation of microstructure formation in castings. The advantage of using the stochastic approach is to give a time- and space-dependent description of solidification processes. Time- and space-dependent processes can also be described by partial differential equations. Unlike a differential formulation which, in most cases, has to be transformed into a difference equation and solved numerically, the stochastic approach is essentially a direct numerical algorithm. The stochastic model is comprehensive, since the competition between various phases is considered. Furthermore, grain impingement is directly included through the structure of the model. In the present research, all grain morphologies are simulated with this procedure. The relevance of the stochastic approach is that the simulated microstructures can be directly compared with microstructures obtained from experiments. The computer becomes a `dynamic metallographic microscope'. A comparison between deterministic and stochastic approaches has been performed. An important objective of this research was to answer the following general questions: (1) `Would fully deterministic approaches continue to be useful in solidification modelling?' and (2) `Would stochastic algorithms be capable of entirely replacing purely deterministic models?'

  12. A hybrid method for solutes in complex solvents: Density functional theory combined with empirical force fields

    NASA Astrophysics Data System (ADS)

    Eichinger, M.; Tavan, P.; Hutter, J.; Parrinello, M.

    1999-06-01

    We present a hybrid method for molecular dynamics simulations of solutes in complex solvents as represented, for example, by substrates within enzymes. The method combines a quantum mechanical (QM) description of the solute with a molecular mechanics (MM) approach for the solvent. The QM fragment of a simulation system is treated by ab initio density functional theory (DFT) based on plane-wave expansions. Long-range Coulomb interactions within the MM fragment and between the QM and the MM fragment are treated by a computationally efficient fast multipole method. For the description of covalent bonds between the two fragments, we introduce the scaled position link atom method (SPLAM), which removes the shortcomings of related procedures. The various aspects of the hybrid method are scrutinized through test calculations on liquid water, the water dimer, ethane and a small molecule related to the retinal Schiff base. In particular, the extent to which vibrational spectra obtained by DFT for the solute can be spoiled by the lower quality force field of the solvent is checked, including cases in which the two fragments are covalently joined. The results demonstrate that our QM/MM hybrid method is especially well suited for the vibrational analysis of molecules in condensed phase.

  13. Theoretical study of the kinetics of chlorine atom abstraction from chloromethanes by atomic chlorine.

    PubMed

    Brudnik, Katarzyna; Twarda, Maria; Sarzyński, Dariusz; Jodkowski, Jerzy T

    2013-10-01

    Ab initio calculations at the G3 level were used in a theoretical description of the kinetics and mechanism of the chlorine abstraction reactions from mono-, di-, tri- and tetra-chloromethane by chlorine atoms. The calculated profiles of the potential energy surface of the reaction systems show that the mechanism of the studied reactions is complex and the Cl-abstraction proceeds via the formation of intermediate complexes. The multi-step reaction mechanism consists of two elementary steps in the case of CCl4 + Cl, and three for the other reactions. Rate constants were calculated using the theoretical method based on the RRKM theory and the simplified version of the statistical adiabatic channel model. The temperature dependencies of the calculated rate constants can be expressed, in temperature range of 200-3,000 K as [Formula: see text]. The rate constants for the reverse reactions CH3/CH2Cl/CHCl2/CCl3 + Cl2 were calculated via the equilibrium constants derived theoretically. The kinetic equations [Formula: see text] allow a very good description of the reaction kinetics. The derived expressions are a substantial supplement to the kinetic data necessary to describe and model the complex gas-phase reactions of importance in combustion and atmospheric chemistry.

  14. Reading and Mathematics Observation System: Description and Measurement of Time Usage in the Classroom.

    ERIC Educational Resources Information Center

    Calfee, Robert C.; Calfee, Kathryn Hoover

    The Beginning Teacher Evaluation Study, Phase II, was a research project on effective teaching behavior--what teachers do that significantly affects what and how pupils learn. The purposes of Phase II were to (1) develop an assessment system for measuring teacher and student behaviors and other factors which could influence each of them and their…

  15. Basic Skills Resource Center. Part 2

    DTIC Science & Technology

    1985-05-01

    side if neceseary and Identify by block number) Basic Skills Education Curriculum Development Learning Strategies Reading Comprehension Motivational ... Motivational Skills Training for Military Technical Training Students ...... Barbara L. McCombs 25 Problem 27 Purpose 27 Approach 28 - Phase 1 28 - Phase...and Learning ...... John J. Hedl , Jr. 53 Purpose of Project 55 Description of Work 55 V Products 56 Virtual Videodisc Software Requirements ...... J.D

  16. Observable phase factors and symmetry of electric and magnetic charges

    NASA Technical Reports Server (NTRS)

    Hsu, J. P.

    1978-01-01

    The observable phase factor is taken as a basic concept for the description of electromagnetism. Generalization of this concept to SU(2) and SU(2) x U(1) groups is carried out in such a way that the monopoles with quantized charges appear naturally and that the symmetry between the electric and magnetic phenomena is preserved. Some physical implications are discussed.

  17. Testing the kibble-zurek scenario with annular josephson tunnel junctions

    PubMed

    Kavoussanaki; Monaco; Rivers

    2000-10-16

    In parallel with Kibble's description of the onset of phase transitions in the early Universe, Zurek has provided a simple picture for the onset of phase transitions in condensed matter systems, supported by agreement with experiments in 3He and superconductors. We show how experiments with annular Josephson tunnel junctions can, and do, provide further support for this scenario.

  18. The Forest Inventory and Analysis Database: Database description and users manual version 4.0 for Phase 2

    Treesearch

    Sharon W. Woudenberg; Barbara L. Conkling; Barbara M. O' Connell; Elizabeth B. LaPoint; Jeffery A. Turner; Karen L. Waddell

    2010-01-01

    This document is based on previous documentation of the nationally standardized Forest Inventory and Analysis database (Hansen and others 1992; Woudenberg and Farrenkopf 1995; Miles and others 2001). Documentation of the structure of the Forest Inventory and Analysis database (FIADB) for Phase 2 data, as well as codes and definitions, is provided. Examples for...

  19. Control of small phased-array antennas

    NASA Technical Reports Server (NTRS)

    Doland, G. D.

    1978-01-01

    Series of reports, patent descriptions, calculator programs, and other literature describes antenna control and steering apparatus for seven-element phased array. Though series contains information specific to particular system, it illustrates methods that can be applied to antennas with greater or fewer numbers of elements. Included are programs for calculating beam parameters and design functions and information to interfacing digital controller to beam-steering apparatus.

  20. Hysteresis in the phase transition of chocolate

    NASA Astrophysics Data System (ADS)

    Ren, Ruilong; Lu, Qunfeng; Lin, Sihua; Dong, Xiaoyan; Fu, Hao; Wu, Shaoyi; Wu, Minghe; Teng, Baohua

    2016-01-01

    We designed an experiment to reproduce the hysteresis phenomenon of chocolate appearing in the heating and cooling process, and then established a model to relate the solidification degree to the order parameter. Based on the Landau-Devonshire theory, our model gave a description of the hysteresis phenomenon in chocolate, which lays the foundations for the study of the phase transition behavior of chocolate.

  1. Description of 103 Cases of Hypobaric Sickness from NASA-sponsored Research

    NASA Technical Reports Server (NTRS)

    Conkin, Johnny; Klein, Jill S.; Acock, Keena E.

    2003-01-01

    One hundred and three cases of hypobaric decompression sickness (DCS) are documented, with 6 classified as Type II DCS. The presence and grade of venous gas emboli (VGE) are part of the case descriptions. Cases were diagnosed from 731 exposures in 5 different altitude chambers from 4 different laboratories between the years 1982 and 1999. Research was funded by NASA to develop operational prebreathe (PB) procedures that would permit safe extravehicular activity from the Space Shuttle and International Space Station using an extravehicular mobility unit (spacesuit) operated at 4.3 psia. Both vehicles operate at 14.7 psia with an "air" atmosphere, so a PB procedure is required to reduce nitrogen partial pressure in the tissues to an acceptable level prior to depressurization to 4.3 psia. Thirty-two additional descriptions of symptoms that were not diagnosed as DCS together with VGE information are also included. The information for each case resides in logbooks from 32 different tests. Additional information is stored in the NASA Decompression Sickness Database and the Prebreathe Reduction Protocol Database, both maintained by the Environmental Physiology Laboratory at the Johnson Space Center. Both sources were reviewed to provide the narratives that follow.

  2. Phase 111A Crew Interface Specifications Development for Inflight Maintenance and Stowage Functions

    NASA Technical Reports Server (NTRS)

    Carl, John G.

    1973-01-01

    This report presents the findings and data products developed during the Phase IIIA Crew Interface Specification Study for Inflight Maintenance and Stowage Functions, performed by General Electric for the NASA, Johnson Space Center with a set of documentation that can be used as definitive guidelines to improve the present process of defining, controlling and managing flight crew interface requirements that are related to inflight maintenance (including assembly and servicing) and stowage functions. During the Phase IIIA contract period, the following data products were developed: 1) Projected NASA Crew Procedures/Flight Data File Development Process. 2) Inflight Maintenance Management Process Description. 3) Preliminary Draft, General Specification, Inflight Maintenance Management Requirements. 4) Inflight Maintenance Operational Process Description. 5) Preliminary Draft, General Specification, Inflight Maintenance Task and Support Requirements Analysis. 6) Suggested IFM Data Processing Reports for Logistics Management The above Inflight Maintenance data products have been developed during the Phase IIIA study after review of Space Shuttle Program Documentation, including the Level II Integrated Logistics Requirements and other DOD and NASA data relative to Payloads Accommodations and Satellite On-Orbit Servicing. These Inflight Maintenance data products were developed to be in consonance with Space Shuttle Program technical and management requirements.

  3. Levodopa enhances explicit new-word learning in healthy adults: a preliminary study.

    PubMed

    Shellshear, Leanne; MacDonald, Anna D; Mahoney, Jeffrey; Finch, Emma; McMahon, Katie; Silburn, Peter; Nathan, Pradeep J; Copland, David A

    2015-09-01

    While the role of dopamine in modulating executive function, working memory and associative learning has been established; its role in word learning and language processing more generally is not clear. This preliminary study investigated the impact of increased synaptic dopamine levels on new-word learning ability in healthy young adults using an explicit learning paradigm. A double-blind, placebo-controlled, between-groups design was used. Participants completed five learning sessions over 1 week with levodopa or placebo administered at each session (five doses, 100 mg). Each session involved a study phase followed by a test phase. Test phases involved recall and recognition tests of the new (non-word) names previously paired with unfamiliar objects (half with semantic descriptions) during the study phase. The levodopa group showed superior recall accuracy for new words over five learning sessions compared with the placebo group and better recognition accuracy at a 1-month follow-up for words learnt with a semantic description. These findings suggest that dopamine boosts initial lexical acquisition and enhances longer-term consolidation of words learnt with semantic information, consistent with dopaminergic enhancement of semantic salience. Copyright © 2015 John Wiley & Sons, Ltd.

  4. Computer Simulations of Polytetrafluoroethylene in the Solid State

    NASA Astrophysics Data System (ADS)

    Holt, D. B.; Farmer, B. L.; Eby, R. K.; Macturk, K. S.

    1996-03-01

    Force field parameters (Set I) for fluoropolymers were previously derived from MOPAC AM1 semiempirical data on model molecules. A second set (Set II) was derived from the AM1 results augmented by ab initio calculations. Both sets yield reasonable helical and phase II packing structures for polytetrafluoroethylene (PTFE) chains. However, Set I and Set II differ in the strength of van der Waals interactions, with Set II having deeper potential wells (order of magnitude). To differentiate which parameter set provides a better description of PTFE behavior, molecular dynamics simulations have been performed with Biosym Discover on clusters of PTFE chains which begin in a phase II packing environment. Added to the model are artificial constraints which allow the simulation of thermal expansion without having to define periodic boundary conditions for each specific temperature of interest. The preliminary dynamics simulations indicate that the intra- and intermolecular interactions provided by Set I are too weak. The degree of helical disorder and chain motion are high even at temperatures well below the phase II-phase IV transition temperature (19 C). Set II appears to yield a better description of PTFE in the solid state.

  5. Emergent geometric description for a topological phase transition in the Kitaev superconductor model

    NASA Astrophysics Data System (ADS)

    Kim, Ki-Seok; Park, Miok; Cho, Jaeyoon; Park, Chanyong

    2017-10-01

    Resorting to Wilsonian renormalization group (RG) transformations, we propose an emergent geometric description for a topological phase transition in the Kitaev superconductor model. An effective field theory consists of an emergent bulk action with an extra dimension, an ultraviolet (UV) boundary condition for an initial value of a coupling function, and an infrared (IR) effective action with a fully renormalized coupling function. The bulk action describes the evolution of the coupling function along the direction of the extra dimension, where the extra dimension is identified with an RG scale and the resulting equation of motion is nothing but a β function. In particular, the IR effective field theory turns out to be consistent with a Callan-Symanzik equation which takes into account both the bulk and IR boundary contributions. This derived Callan-Symanzik equation gives rise to a metric structure. Based on this emergent metric tensor, we uncover the equivalence of the entanglement entropy between the emergent geometric description and the quantum field theory in the vicinity of the quantum critical point.

  6. Manipulating topological-insulator properties using quantum confinement

    NASA Astrophysics Data System (ADS)

    Kotulla, M.; Zülicke, U.

    2017-07-01

    Recent discoveries have spurred the theoretical prediction and experimental realization of novel materials that have topological properties arising from band inversion. Such topological insulators are insulating in the bulk but have conductive surface or edge states. Topological materials show various unusual physical properties and are surmised to enable the creation of exotic Majorana-fermion quasiparticles. How the signatures of topological behavior evolve when the system size is reduced is interesting from both a fundamental and an application-oriented point of view, as such understanding may form the basis for tailoring systems to be in specific topological phases. This work considers the specific case of quantum-well confinement defining two-dimensional layers. Based on the effective-Hamiltonian description of bulk topological insulators, and using a harmonic-oscillator potential as an example for a softer-than-hard-wall confinement, we have studied the interplay of band inversion and size quantization. Our model system provides a useful platform for systematic study of the transition between the normal and topological phases, including the development of band inversion and the formation of massless-Dirac-fermion surface states. The effects of bare size quantization, two-dimensional-subband mixing, and electron-hole asymmetry are disentangled and their respective physical consequences elucidated.

  7. Multipartite entangled states in particle mixing

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

    Blasone, M.; INFN Sezione di Napoli, Gruppo collegato di Salerno, Baronissi; Dell'Anno, F.

    2008-05-01

    In the physics of flavor mixing, the flavor states are given by superpositions of mass eigenstates. By using the occupation number to define a multiqubit space, the flavor states can be interpreted as multipartite mode-entangled states. By exploiting a suitable global measure of entanglement, based on the entropies related to all possible bipartitions of the system, we analyze the correlation properties of such states in the instances of three- and four-flavor mixing. Depending on the mixing parameters, and, in particular, on the values taken by the free phases, responsible for the CP-violation, entanglement concentrates in certain bipartitions. We quantify inmore » detail the amount and the distribution of entanglement in the physically relevant cases of flavor mixing in quark and neutrino systems. By using the wave packet description for localized particles, we use the global measure of entanglement, suitably adapted for the instance of multipartite mixed states, to analyze the decoherence, induced by the free evolution dynamics, on the quantum correlations of stationary neutrino beams. We define a decoherence length as the distance associated with the vanishing of the coherent interference effects among massive neutrino states. We investigate the role of the CP-violating phase in the decoherence process.« less

  8. Intelligent process control of fiber chemical vapor deposition

    NASA Astrophysics Data System (ADS)

    Jones, John Gregory

    Chemical Vapor Deposition (CVD) is a widely used process for the application of thin films. In this case, CVD is being used to apply a thin film interface coating to single crystal monofilament sapphire (Alsb2Osb3) fibers for use in Ceramic Matrix Composites (CMC's). The hot-wall reactor operates at near atmospheric pressure which is maintained using a venturi pump system. Inert gas seals obviate the need for a sealed system. A liquid precursor delivery system has been implemented to provide precise stoichiometry control. Neural networks have been implemented to create real-time process description models trained using data generated based on a Navier-Stokes finite difference model of the process. Automation of the process to include full computer control and data logging capability is also presented. In situ sensors including a quadrupole mass spectrometer, thermocouples, laser scanner, and Raman spectrometer have been implemented to determine the gas phase reactants and coating quality. A fuzzy logic controller has been developed to regulate either the gas phase or the in situ temperature of the reactor using oxygen flow rate as an actuator. Scanning electron microscope (SEM) images of various samples are shown. A hierarchical control structure upon which the control structure is based is also presented.

  9. A Framework for Performing V&V within Reuse-Based Software Engineering

    NASA Technical Reports Server (NTRS)

    Addy, Edward A.

    1996-01-01

    Verification and validation (V&V) is performed during application development for many systems, especially safety-critical and mission-critical systems. The V&V process is intended to discover errors, especially errors related to critical processing, as early as possible during the development process. Early discovery is important in order to minimize the cost and other impacts of correcting these errors. In order to provide early detection of errors, V&V is conducted in parallel with system development, often beginning with the concept phase. In reuse-based software engineering, however, decisions on the requirements, design and even implementation of domain assets can be made prior to beginning development of a specific system. In this case, V&V must be performed during domain engineering in order to have an impact on system development. This paper describes a framework for performing V&V within architecture-centric, reuse-based software engineering. This framework includes the activities of traditional application-level V&V, and extends these activities into domain engineering and into the transition between domain engineering and application engineering. The framework includes descriptions of the types of activities to be performed during each of the life-cycle phases, and provides motivation for the activities.

  10. [Demographic and clinical aspects of hepatic fascioliasis between 2013-2010 in National Hospital Cayetano Heredia, Lima, Peru].

    PubMed

    Chang Wong, Millie Rocío; Pinto Elera, Jesús Omar Andrés; Guzman Rojas, Patricia; Terashima Iwashita, Angélica; Samalvides Cuba, Frine

    2016-01-01

    To describe the demographic and clinical aspects of hepatic fascioliasis as well as the complications and associations between various factors and the disease in a reference hospital. This is a descriptive and retrospective case series study; we included all patients who had a recent diagnosis of hepatic fascioliasis from 2003 to 2010 in the Hospital Nacional Cayetano Heredia. Demographic and clinical variables were analyzed including complications and treatment received. 68 medical records were found eligible for the study. The mean age was 36 years. Ancash department was the most frequent place of origin and residence. Most of them were diagnosed in the chronic phase, the most common symptom was abdominal pain and eight patients had complications: 3 hepatic abscess, 1 subcapsular hematoma, 1 cholangitis and 1 cholangitis plus cholecystitis. There were the following associations: Age under 15 years with chronic phase and hyporexia, being a student with a positive stool analysis; and between being born in an endemic area with the absence of complications. Hepatic fascioliasis has unspecific clinical presentation so the epidemiological or dietary history and specially eosinophilia should guide the diagnosis.

  11. Application of the anisotropic phase-field crystal model to investigate the lattice systems of different anisotropic parameters and orientations

    NASA Astrophysics Data System (ADS)

    Kundin, Julia; Ajmal Choudhary, Muhammad

    2017-07-01

    In this article, we present the recent advances in the development of the anisotropic phase-field crystal (APFC) model. These advances are important in basic researches for multiferroic and thermoelectric materials with anisotropic crystal lattices and in thin-film applications. We start by providing a general description of the model derived in our previous studies based on the crystal symmetry and the microscopic dynamical density functional theory for anisotropic interactions and show that there exist only two possible degrees of freedom for the anisotropic lattices which are described by two independent parameters. New findings concerning the applications of the APFC model for the estimation of the elastic modules of anisotropic systems including sheared and stretched lattices as well as for the investigation of the heterogeneous thin film growth are described. The simulation results demonstrate the strong dependency of the misfit dislocation formation during the film growth on the anisotropy and reveal the asymmetric behavior in the cases of positive and negative misfits. We also present the development of the amplitude representation for the full APFC model of two orientation variants and show the relationship between the wave vectors and the base angles of the anisotropic lattices.

  12. Making the case for evidence-based design in healthcare: a descriptive case study of organizational decision making.

    PubMed

    Shoemaker, Lorie K; Kazley, Abby Swanson; White, Andrea

    2010-01-01

    The aim of this study was to describe the organizational decision-making process used in the selection of evidence-based design (EBD) concepts, the criteria used to make these decisions, and the extent to which leadership style may have influenced the decision-making process. Five research questions were formulated to frame the direction of this study, including: (1) How did healthcare leaders learn of innovations in design? (2) How did healthcare leaders make decisions in the selection of healthcare design concepts? (3) What criteria did healthcare leaders use in the decision-making process? (4) How did healthcare leaders consider input from the staff in design decisions? and (5) To what extent did the leadership style of administrators affect the outcomes of the decision-making process? Current issues affecting healthcare in the community led the principal investigator's organization to undertake an ambitious facilities expansion project. As part of its planning process, the organization learned of EBD principles that seemingly had a positive impact on patient care and safety and staff working conditions. Although promising, a paucity of empirical research addressed the cost/benefit of incorporating many EBD concepts into one hospital setting, and there was no research that articulated the organizational decision-making process used by healthcare administrators when considering the use of EBD in expansion projects. A mixed-method, descriptive, qualitative, single-case study and quantitative design were used to address the five research questions. The Systems Research Organizing Model provided the theoretical framework. A variety of data collection methods was used, including interviews of key respondents, the review of documentary evidence, and the Multifactor Leadership Questionnaire. A participatory process was used throughout the design decision phases, involving staff at all levels of the organization. The Internet and architects facilitated learning about EBD. Financial considerations were a factor in decision making. The prevalence of the transformational leadership style among the organization's administrators exceeded the U.S. mean.

  13. An investigation of wing buffeting response at subsonic and transonic speeds: Phase 1: F-111A flight data analysis. Volume 1: Summary of technical approach, results and conclusions

    NASA Technical Reports Server (NTRS)

    Benepe, D. B.; Cunningham, A. M., Jr.; Dunmyer, W. D.

    1978-01-01

    The structural response to aerodynamic buffet during moderate to high-g maneuvers at subsonic and transonic speeds was investigated. The investigation is reported in three volumes. This volume presents a summary of the investigation with a complete description of the technical approach, description of the aircraft, its instrumentation, the data reduction procedures, results and conclusion.

  14. Operation and Maintenance Manual, TECS 18.

    DTIC Science & Technology

    1978-11-01

    width modulated variable output voltage and frequency using a three-phase transistor bridge circuit . Reduced power line electromagnetic interference...Description 3-1 Section II. Circuit Fundamentals 3-1 Section III. System Description 3-2 CHAPTER 4. Protection and Maintenance 4-1 Section I. Internal...Number I-la TECS 18 Electronic Module Location-Evaporator Side 1-3 1-lb TECS 18 Electronic Module Location-Condenser Side 1-4 1-2 Remote Control Panel 1-5

  15. Tracking and data systems support for the Helios project. Volume 1: Project development through end of mission, phase 2

    NASA Technical Reports Server (NTRS)

    Goodwin, P. S.; Traxler, M. R.; Meeks, W. G.; Flanagan, F. M.

    1976-01-01

    The overall evolution of the Helios Project is summarized from its conception through to the completion of the Helios-1 mission phase 2. Beginning with the project objectives and concluding with the Helios-1 spacecraft entering its first superior conjunction (end of mission phase 2), descriptions of the project, the mission and its phases, international management and interfaces, and Deep Space Network-spacecraft engineering development in telemetry, tracking, and command systems to ensure compatibility between the U.S. Deep Space Network and the German-built spacecraft are included.

  16. Study of anyon condensation and topological phase transitions from a Z4 topological phase using the projected entangled pair states approach

    NASA Astrophysics Data System (ADS)

    Iqbal, Mohsin; Duivenvoorden, Kasper; Schuch, Norbert

    2018-05-01

    We use projected entangled pair states (PEPS) to study topological quantum phase transitions. The local description of topological order in the PEPS formalism allows us to set up order parameters which measure condensation and deconfinement of anyons and serve as substitutes for conventional order parameters. We apply these order parameters, together with anyon-anyon correlation functions and some further probes, to characterize topological phases and phase transitions within a family of models based on a Z4 symmetry, which contains Z4 quantum double, toric code, double semion, and trivial phases. We find a diverse phase diagram which exhibits a variety of different phase transitions of both first and second order which we comprehensively characterize, including direct transitions between the toric code and the double semion phase.

  17. Overcoming Fear of Eating: A Case Study of a Novel Use of Exposure and Response Prevention

    PubMed Central

    Glasofer, Deborah R.; Albano, Anne Marie; Simpson, H. Blair; Steinglass, Joanna E.

    2016-01-01

    Even after successful weight restoration, many patients with anorexia nervosa (AN) continue to exhibit maladaptive eating including repetitive behaviors (i.e., food rituals) used to decrease anxiety about food, and to describe fears related to food content its effect on shape and weight. While there are important differences between eating disorders and anxiety disorders, the shared clinical phenomena suggest potentially useful overlap in treatment strategies. This case study will describe treatment of a woman with AN using Exposure and Response Prevention for Anorexia Nervosa (AN-EXRP) as an adjunct to concurrent inpatient treatment. This is a novel use of a treatment approach with established efficacy in the treatment of anxiety disorders. AN-EXRP specifically targets eating-related anxiety with the intent to improve the restrictive eating patterns that persist after acute weight restoration. The case study described includes descriptions of (1) the treatment rationale and its phases of implementation, (2) illustrative sample dialogue between the patient and therapist, (3) pre- and post-treatment data on outcome measures of interest (e.g., food intake at a laboratory meal, self-report anxiety ratings, self-report eating-related rituals and preoccupations), and (4) therapist considerations (e.g., maintaining alliance, adhering to treatment frame). PMID:27267508

  18. Vibrational spectroscopy via the Caldeira-Leggett model with anharmonic system potentials

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

    Gottwald, Fabian; Ivanov, Sergei D., E-mail: sergei.ivanov@uni-rostock.de; Kühn, Oliver

    2016-04-28

    The Caldeira-Leggett (CL) model, which describes a system bi-linearly coupled to a harmonic bath, has enjoyed popularity in condensed phase spectroscopy owing to its utmost simplicity. However, the applicability of the model to cases with anharmonic system potentials, as it is required for the description of realistic systems in solution, is questionable due to the presence of the invertibility problem [F. Gottwald et al., J. Phys. Chem. Lett. 6, 2722 (2015)] unless the system itself resembles the CL model form. This might well be the case at surfaces or in the solid regime, which we here confirm for a particularmore » example of an iodine molecule in the atomic argon environment under high pressure. For this purpose we extend the recently proposed Fourier method for parameterizing linear generalized Langevin dynamics [F. Gottwald et al., J. Chem. Phys. 142, 244110 (2015)] to the non-linear case based on the CL model and perform an extensive error analysis. In order to judge on the applicability of this model in advance, we give practical empirical criteria and discuss the effect of the potential renormalization term. The obtained results provide evidence that the CL model can be used for describing a potentially broad class of systems.« less

  19. Practice Report / Bericht aus der Praxis: An exploration of peer tutor roles and recruitment at German medical schools.

    PubMed

    Alvarez, Simone; Schultz, Jobst-Hendrik

    2017-11-01

    Almost all medical faculties in Germany actively employ peer tutors. However, little is known about the roles these tutors play from a faculty point of view. Also, there are only few descriptions of the tutor recruitment and selection processes. 32 of the medical faculties in Germany, where tutors are used in the training of medical students, were asked to provide information on the role and recruitment of tutors by means of a partially standardized questionnaire. At the surveyed faculties (return rate 28%), tutors are mostly employed for the purpose of teaching staff support. Even though desired in individual cases, tutors rarely play an active role in curriculum- or faculty development. The way tutor recruitment is handled strongly depends on the capabilities of the individual faculties and the way tutors are utilized. In many cases this process is structured, consisting of written and oral application phases, in other cases recruitment takes place without formal application procedures. The selection criteria, however, were found to be very similar at most faculties. The role of tutors from the faculties' point of view depends strongly on the respective nature of the tutorials, which are just as diverse as the approaches to tutor recruitment. Copyright © 2017. Published by Elsevier GmbH.

  20. Overcoming fear of eating: A case study of a novel use of exposure and response prevention.

    PubMed

    Glasofer, Deborah R; Albano, Anne Marie; Simpson, H Blair; Steinglass, Joanna E

    2016-06-01

    Even after successful weight restoration, many patients with anorexia nervosa (AN) continue to exhibit maladaptive eating including repetitive behaviors (i.e., food rituals) used to decrease anxiety about food, and to describe fears related to food content, including its effect on shape and weight. Although there are important differences between eating disorders and anxiety disorders, the shared clinical phenomena suggest potentially useful overlap in treatment strategies. This case study will describe treatment of a woman with AN using Exposure and Response Prevention for Anorexia Nervosa (AN-EXRP) as an adjunct to concurrent inpatient treatment. This is a novel use of a treatment approach with established efficacy in the treatment of anxiety disorders. AN-EXRP specifically targets eating-related anxiety with the intent to improve the restrictive eating patterns that persist after acute weight restoration. The case study described includes descriptions of (a) the treatment rationale and its phases of implementation, (b) illustrative sample dialogue between the patient and therapist, (c) pre- and posttreatment data on outcome measures of interest (e.g., food intake at a laboratory meal, self-report anxiety ratings, self-report eating-related rituals, and preoccupations), and (d) therapist considerations (e.g., maintaining alliance, adhering to treatment frame). (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  1. [Orthopedic and trauma surgery in the German DRG system. Recent developments].

    PubMed

    Franz, D; Schemmann, F; Selter, D D; Wirtz, D C; Roeder, N; Siebert, H; Mahlke, L

    2012-07-01

    Orthopedics and trauma surgery are subject to continuous medical advancement. The correct and performance-based case allocation by German diagnosis-related groups (G-DRG) is a major challenge. This article analyzes and assesses current developments in orthopedics and trauma surgery in the areas of coding of diagnoses and medical procedures and the development of the 2012 G-DRG system. The relevant diagnoses, medical procedures and G-DRGs in the versions 2011 and 2012 were analyzed based on the publications of the German DRG Institute (InEK) and the German Institute of Medical Documentation and Information (DIMDI). Changes were made for the International Classification of Diseases (ICD) coding of complex cases with medical complications, the procedure coding for spinal surgery and for hand and foot surgery. The G-DRG structures were modified for endoprosthetic surgery on ankle, shoulder and elbow joints. The definition of modular structured endoprostheses was clarified. The G-DRG system for orthopedic and trauma surgery appears to be largely consolidated. The current phase of the evolution of the G-DRG system is primarily aimed at developing most exact descriptions and definitions of the content and mutual delimitation of operation and procedures coding (OPS). This is an essential prerequisite for a correct and performance-based case allocation in the G-DRG system.

  2. Atomic collisions in the presence of laser radiation - Time dependence and the asymptotic wave function

    NASA Technical Reports Server (NTRS)

    Devries, P. L.; George, T. F.

    1982-01-01

    A time-dependent, wave-packet description of atomic collisions in the presence of laser radiation is extracted from the more conventional time-independent, stationary-state description. This approach resolves certain difficulties of interpretation in the time-independent approach which arise in the case of asymptotic near resonance. In the two-state model investigated, the approach predicts the existence of three spherically scattered waves in this asymptotically near-resonant case.

  3. Space Station automated systems testing/verification and the Galileo Orbiter fault protection design/verification

    NASA Technical Reports Server (NTRS)

    Landano, M. R.; Easter, R. W.

    1984-01-01

    Aspects of Space Station automated systems testing and verification are discussed, taking into account several program requirements. It is found that these requirements lead to a number of issues of uncertainties which require study and resolution during the Space Station definition phase. Most, if not all, of the considered uncertainties have implications for the overall testing and verification strategy adopted by the Space Station Program. A description is given of the Galileo Orbiter fault protection design/verification approach. Attention is given to a mission description, an Orbiter description, the design approach and process, the fault protection design verification approach/process, and problems of 'stress' testing.

  4. Relationship between mandibular second molar calcification stages and cervical vertebrae maturity in Italian children and young adults.

    PubMed

    Cossellu, G; Biagi, R; Pisani, L; Barbieri, V; Farronato, G

    2014-12-01

    The aim of this study was to investigate the relationship between the stages of calcification of the mandibular second molar and the stages of skeletal maturity among Italian children and young adults. Cross-sectional descriptive study. The samples were derived from panoramic radiographs and lateral cephalograms of 500 Italian subjects aged from 10 to 20 years. Dental maturity index (DM) was assessed by calcification stages of the mandibular second molars according to the Demirjian method; skeletal maturity was evaluated with cervical vertebrae maturation index (CVM) according to Hassel and Farman. The Pearson r coefficient and Spearman rank correlation coefficient were estimated to determine the relationship between DM and CVM. Skeletal maturation stages occurred earlier in females (about 6 months). A highly significant correlation between CVM and DM (0.78-0.86 cor according to Pearson test and 0.81-0.85 rho according to Spearman test) was found. DM stage E corresponds to phase CVM 1 and 2 (the phase prior to the growth spurt), DM stage F corresponds to the phase of pubertal growth spurt, stages CVM 2 and CVM 3; DM stage G is indicator of the growth spurt underway (CVM 3-4), but it can still be found during CVM 5 in females. The second mandibular molars can be considered reliable indicators for the evaluation of the growth phases. In case of females the end of the growth spurt it is not clearly associated with a dental maturity stage and needs to be stated with further parameters such as CVM.

  5. Antiferromagnetism, charge density wave, and d-wave superconductivity in the extended t-J-U model: role of intersite Coulomb interaction and a critical overview of renormalized mean field theory.

    PubMed

    Abram, M; Zegrodnik, M; Spałek, J

    2017-09-13

    In the first part of the paper, we study the stability of antiferromagnetic (AF), charge density wave (CDW), and superconducting (SC) states within the t-J-U-V model of strongly correlated electrons by using the statistically consistent Gutzwiller approximation (SGA). We concentrate on the role of the intersite Coulomb interaction term V in stabilizing the CDW phase. In particular, we show that the charge ordering appears only above a critical value of V in a limited hole-doping range δ. The effect of the V term on SC and AF phases is that a strong interaction suppresses SC, whereas the AF order is not significantly influenced by its presence. In the second part, separate calculations for the case of a pure SC phase have been carried out within an extended approach (the diagrammatic expansion for the Gutzwiller wave function, DE-GWF) in order to analyze the influence of the intersite Coulomb repulsion on the SC phase with the higher-order corrections included beyond the SGA method. The upper concentration for the SC disappearance decreases with increasing V, bringing the results closer to experiment. In appendices A and B we discuss the ambiguity connected with the choice of the Gutzwiller renormalization factors within the renormalized mean filed theory when either AF or CDW orders are considered. At the end, we overview briefly the possible extensions of the current models to put descriptions of the SC, AF, and CDW states on equal footing.

  6. Molecular Modeling of Thermodynamic and Transport Properties for CO 2 and Aqueous Brines

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

    Jiang, Hao; Economou, Ioannis G.; Panagiotopoulos, Athanassios Z.

    Molecular simulation techniques using classical force-fields occupy the space between ab initio quantum mechanical methods and phenomenological correlations. In particular, Monte Carlo and molecular dynamics algorithms can be used to provide quantitative predictions of thermodynamic and transport properties of fluids relevant for geologic carbon sequestration at conditions for which experimental data are uncertain or not available. These methods can cover time and length scales far exceeding those of quantum chemical methods, while maintaining transferability and predictive power lacking from phenomenological correlations. The accuracy of predictions depends sensitively on the quality of the molecular models used. Many existing fixed-point-charge models formore » water and aqueous mixtures fail to represent accurately these fluid properties, especially when descriptions covering broad ranges of thermodynamic conditions are needed. Recent work on development of accurate models for water, CO 2, and dissolved salts, as well as their mixtures, is summarized in this Account. Polarizable models that can respond to the different dielectric environments in aqueous versus nonaqueous phases are necessary for predictions of properties over extended ranges of temperatures and pressures. Phase compositions and densities, activity coefficients of the dissolved salts, interfacial tensions, viscosities and diffusivities can be obtained in near-quantitative agreement to available experimental data, using relatively modest computational resources. In some cases, for example, for the composition of the CO 2-rich phase in coexistence with an aqueous phase, recent results from molecular simulations have helped discriminate among conflicting experimental data sets. The sensitivity of properties on the quality of the intermolecular interaction model varies significantly. Properties such as the phase compositions or electrolyte activity coefficients are much more sensitive than phase densities, viscosities, or component diffusivities. Strong confinement effects on physical properties in nanoscale media can also be directly obtained from molecular simulations. Future work on molecular modeling for CO 2 and aqueous brines is likely to be focused on more systematic generation of interaction models by utilizing quantum chemical as well as direct experimental measurements. New ion models need to be developed for use with the current generation of polarizable water models, including ion–ion interactions that will allow for accurate description of dense, mixed brines. Methods will need to be devised that go beyond the use of effective potentials for incorporation of quantum effects known to be important for water, and reactive force fields developed that can handle bond creation and breaking in systems with carbonate and silicate minerals. Lastly, another area of potential future work is the integration of molecular simulation methods in multiscale models for the chemical reactions leading to mineral dissolution and flow within the porous media in underground formations.« less

  7. Molecular Modeling of Thermodynamic and Transport Properties for CO2 and Aqueous Brines.

    PubMed

    Jiang, Hao; Economou, Ioannis G; Panagiotopoulos, Athanassios Z

    2017-04-18

    Molecular simulation techniques using classical force-fields occupy the space between ab initio quantum mechanical methods and phenomenological correlations. In particular, Monte Carlo and molecular dynamics algorithms can be used to provide quantitative predictions of thermodynamic and transport properties of fluids relevant for geologic carbon sequestration at conditions for which experimental data are uncertain or not available. These methods can cover time and length scales far exceeding those of quantum chemical methods, while maintaining transferability and predictive power lacking from phenomenological correlations. The accuracy of predictions depends sensitively on the quality of the molecular models used. Many existing fixed-point-charge models for water and aqueous mixtures fail to represent accurately these fluid properties, especially when descriptions covering broad ranges of thermodynamic conditions are needed. Recent work on development of accurate models for water, CO 2 , and dissolved salts, as well as their mixtures, is summarized in this Account. Polarizable models that can respond to the different dielectric environments in aqueous versus nonaqueous phases are necessary for predictions of properties over extended ranges of temperatures and pressures. Phase compositions and densities, activity coefficients of the dissolved salts, interfacial tensions, viscosities and diffusivities can be obtained in near-quantitative agreement to available experimental data, using relatively modest computational resources. In some cases, for example, for the composition of the CO 2 -rich phase in coexistence with an aqueous phase, recent results from molecular simulations have helped discriminate among conflicting experimental data sets. The sensitivity of properties on the quality of the intermolecular interaction model varies significantly. Properties such as the phase compositions or electrolyte activity coefficients are much more sensitive than phase densities, viscosities, or component diffusivities. Strong confinement effects on physical properties in nanoscale media can also be directly obtained from molecular simulations. Future work on molecular modeling for CO 2 and aqueous brines is likely to be focused on more systematic generation of interaction models by utilizing quantum chemical as well as direct experimental measurements. New ion models need to be developed for use with the current generation of polarizable water models, including ion-ion interactions that will allow for accurate description of dense, mixed brines. Methods will need to be devised that go beyond the use of effective potentials for incorporation of quantum effects known to be important for water, and reactive force fields developed that can handle bond creation and breaking in systems with carbonate and silicate minerals. Another area of potential future work is the integration of molecular simulation methods in multiscale models for the chemical reactions leading to mineral dissolution and flow within the porous media in underground formations.

  8. Molecular Modeling of Thermodynamic and Transport Properties for CO 2 and Aqueous Brines

    DOE PAGES

    Jiang, Hao; Economou, Ioannis G.; Panagiotopoulos, Athanassios Z.

    2017-02-24

    Molecular simulation techniques using classical force-fields occupy the space between ab initio quantum mechanical methods and phenomenological correlations. In particular, Monte Carlo and molecular dynamics algorithms can be used to provide quantitative predictions of thermodynamic and transport properties of fluids relevant for geologic carbon sequestration at conditions for which experimental data are uncertain or not available. These methods can cover time and length scales far exceeding those of quantum chemical methods, while maintaining transferability and predictive power lacking from phenomenological correlations. The accuracy of predictions depends sensitively on the quality of the molecular models used. Many existing fixed-point-charge models formore » water and aqueous mixtures fail to represent accurately these fluid properties, especially when descriptions covering broad ranges of thermodynamic conditions are needed. Recent work on development of accurate models for water, CO 2, and dissolved salts, as well as their mixtures, is summarized in this Account. Polarizable models that can respond to the different dielectric environments in aqueous versus nonaqueous phases are necessary for predictions of properties over extended ranges of temperatures and pressures. Phase compositions and densities, activity coefficients of the dissolved salts, interfacial tensions, viscosities and diffusivities can be obtained in near-quantitative agreement to available experimental data, using relatively modest computational resources. In some cases, for example, for the composition of the CO 2-rich phase in coexistence with an aqueous phase, recent results from molecular simulations have helped discriminate among conflicting experimental data sets. The sensitivity of properties on the quality of the intermolecular interaction model varies significantly. Properties such as the phase compositions or electrolyte activity coefficients are much more sensitive than phase densities, viscosities, or component diffusivities. Strong confinement effects on physical properties in nanoscale media can also be directly obtained from molecular simulations. Future work on molecular modeling for CO 2 and aqueous brines is likely to be focused on more systematic generation of interaction models by utilizing quantum chemical as well as direct experimental measurements. New ion models need to be developed for use with the current generation of polarizable water models, including ion–ion interactions that will allow for accurate description of dense, mixed brines. Methods will need to be devised that go beyond the use of effective potentials for incorporation of quantum effects known to be important for water, and reactive force fields developed that can handle bond creation and breaking in systems with carbonate and silicate minerals. Lastly, another area of potential future work is the integration of molecular simulation methods in multiscale models for the chemical reactions leading to mineral dissolution and flow within the porous media in underground formations.« less

  9. HAL/S-FC and HAL/S-360 compiler system program description

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The compiler is a large multi-phase design and can be broken into four phases: Phase 1 inputs the source language and does a syntactic and semantic analysis generating the source listing, a file of instructions in an internal format (HALMAT) and a collection of tables to be used in subsequent phases. Phase 1.5 massages the code produced by Phase 1, performing machine independent optimization. Phase 2 inputs the HALMAT produced by Phase 1 and outputs machine language object modules in a form suitable for the OS-360 or FCOS linkage editor. Phase 3 produces the SDF tables. The four phases described are written in XPL, a language specifically designed for compiler implementation. In addition to the compiler, there is a large library containing all the routines that can be explicitly called by the source language programmer plus a large collection of routines for implementing various facilities of the language.

  10. Security Quality Requirements Engineering (SQUARE): Case Study Phase III

    DTIC Science & Technology

    2006-05-01

    Security Quality Requirements Engineering (SQUARE): Case Study Phase III Lydia Chung Frank Hung Eric Hough Don Ojoko-Adams Advisor...Engineering (SQUARE): Case Study Phase III CMU/SEI-2006-SR-003 Lydia Chung Frank Hung Eric Hough Don Ojoko-Adams Advisor Nancy R. Mead...1 1.1 The SQUARE Process ............................................................................... 1 1.2 Case Study Clients

  11. Relationships between Descriptive Sensory Attributes and Physicochemical Analysis of Broiler and Taiwan Native Chicken Breast Meat

    PubMed Central

    Chumngoen, Wanwisa; Tan, Fa-Jui

    2015-01-01

    Unique organoleptic characteristics such as rich flavors and chewy texture contribute to the higher popularity of native chicken in many Asian areas, while the commercial broilers are well-accepted due to their fast-growing and higher yields of meat. Sensory attributes of foods are often used to evaluate food eating quality and serve as references during the selection of foods. In this study, a three-phase descriptive sensory study was conducted to evaluate the sensory attributes of commercial broiler (BR) and Taiwan native chicken (TNC) breast meat, and investigate correlations between these sensory attributes and instrumental measurements. The results showed that for the first bite (phase 1), TNC meat had significantly higher moisture release, hardness, springiness, and cohesiveness than BR meat. After chewing for 10 to 12 bites (phase 2), TNC meat presented significantly higher chewdown hardness and meat particle size, whereas BR meat had significantly higher cohesiveness of mass. After swallowing (phase 3), TNC meat had higher chewiness and oily mouthcoat and lower residual loose particles than BR meat. TNC meat also provided more intense chicken flavors. This study clearly demonstrates that descriptive sensory analysis provides more detailed and more objectively information about the sensory attributes of meats from various chicken breeds. Additionally, sensory textural attributes vary between BR and TNC meat, and are highly correlated to the shear force value and collagen content which influence meat eating qualities greatly. The poultry industry and scientists should be able to recognize the sensory characteristics of different chicken meats more clearly. Accordingly, based on the meat’s unique sensory and physicochemical characteristics, future work might address how meat from various breeds could best satisfy consumer needs using various cooking methods. PMID:26104409

  12. Relationships between Descriptive Sensory Attributes and Physicochemical Analysis of Broiler and Taiwan Native Chicken Breast Meat.

    PubMed

    Chumngoen, Wanwisa; Tan, Fa-Jui

    2015-07-01

    Unique organoleptic characteristics such as rich flavors and chewy texture contribute to the higher popularity of native chicken in many Asian areas, while the commercial broilers are well-accepted due to their fast-growing and higher yields of meat. Sensory attributes of foods are often used to evaluate food eating quality and serve as references during the selection of foods. In this study, a three-phase descriptive sensory study was conducted to evaluate the sensory attributes of commercial broiler (BR) and Taiwan native chicken (TNC) breast meat, and investigate correlations between these sensory attributes and instrumental measurements. The results showed that for the first bite (phase 1), TNC meat had significantly higher moisture release, hardness, springiness, and cohesiveness than BR meat. After chewing for 10 to 12 bites (phase 2), TNC meat presented significantly higher chewdown hardness and meat particle size, whereas BR meat had significantly higher cohesiveness of mass. After swallowing (phase 3), TNC meat had higher chewiness and oily mouthcoat and lower residual loose particles than BR meat. TNC meat also provided more intense chicken flavors. This study clearly demonstrates that descriptive sensory analysis provides more detailed and more objectively information about the sensory attributes of meats from various chicken breeds. Additionally, sensory textural attributes vary between BR and TNC meat, and are highly correlated to the shear force value and collagen content which influence meat eating qualities greatly. The poultry industry and scientists should be able to recognize the sensory characteristics of different chicken meats more clearly. Accordingly, based on the meat's unique sensory and physicochemical characteristics, future work might address how meat from various breeds could best satisfy consumer needs using various cooking methods.

  13. NASA SBIR product catalog, 1990

    NASA Technical Reports Server (NTRS)

    Schwenk, F. Carl; Gilman, J. A.

    1990-01-01

    Since 1983 the NASA Small Business Innovation Research (SBIR) program has benefitted both the agency and the high technology small business community. By making it possible for more small businesses to participate in NASA's research and development, SBIR also provides opportunities for these entrepreneurs to develop products which may also have significant commercial markets. Structured in three phases, the SBIR program uses Phase 1 to assess the technical feasibility of novel ideas proposed by small companies and Phase 2 to conduct research and development on the best concepts. Phase 3, not funded by SBIR, is the utilization and/or commercialization phase. A partial list of products of NASA SBIR projects which have advanced to some degree into Phase 3 are provided with a brief description.

  14. Energetics of a two-phase model of lithospheric damage, shear localization and plate-boundary formation

    NASA Astrophysics Data System (ADS)

    Bercovici, David; Ricard, Yanick

    2003-03-01

    The two-phase theory for compaction and damage proposed by Bercovici et al. (2001a, J. Geophys. Res.,106, 8887-8906) employs a nonequilibrium relation between interfacial surface energy, pressure and viscous deformation, thereby providing a model for damage (void generation and microcracking) and a continuum description of weakening, failure and shear localization. Here we examine further variations of the model which consider (1) how interfacial surface energy, when averaged over the mixture, appears to be partitioned between phases; (2) how variability in deformational-work partitioning greatly facilitates localization; and (3) how damage and localization are manifested in heat output and bulk energy exchange. Microphysical considerations of molecular bonding and activation energy suggest that the apparent partitioning of surface energy between phases goes as the viscosity of the phases. When such partitioning is used in the two-phase theory, it captures the melt-compaction theory of McKenzie (1984, J. Petrol.,25, 713-765) exactly, as well as the void-damage theory proposed in a companion paper (Ricard & Bercovici, submitted). Calculations of 1-D shear localization with this variation of the theory still show at least three possible regimes of damage and localization: at low stress is weak localization with diffuse slowly evolving shear bands; at higher stress strong localization with narrow rapidly growing bands exists; and at yet higher shear stress it is possible for the system to undergo broadly distributed damage and no localization. However, the intensity of localization is strongly controlled by the variability of the deformational-work partitioning with dilation rate, represented by the parameter γ. For γ>> 1, extreme localization is allowed, with sharp profiles in porosity (weak zones), nearly discontinuous separation velocities and effectively singular dilation rates. Finally, the bulk heat output is examined for the 1-D system to discern how much deformational work is effectively stored as surface energy. In the high-stress, distributed-damage cases, heat output is reduced as more interfacial surface energy is created. Yet, in either the weak or strong localizing cases, the system always releases surface energy, regardless of the presence of damage or not, and thus slightly more heat is in fact released than energy is input through external work. Moreover, increased levels of damage (represented by the maximum work-partitioning f*) make the localizing system release surface energy faster as damage enhances phase separation and focusing of the porosity field, thus yielding more rapid loss of net interfacial surface area. However, when cases with different levels of damage are compared at similar stages of development (say, the peak porosity of the localization) it is apparent that increased damage causes smaller relative heat release and retards loss of net interfacial surface energy. The energetics and energy partitioning of this damage and shear-localization model are applied to estimating the energy costs of forming plate boundaries and generating plates from mantle convection.

  15. Definition of infection after fracture fixation: A systematic review of randomized controlled trials to evaluate current practice.

    PubMed

    Metsemakers, W J; Kortram, K; Morgenstern, M; Moriarty, T F; Meex, I; Kuehl, R; Nijs, S; Richards, R G; Raschke, M; Borens, O; Kates, S L; Zalavras, C; Giannoudis, P V; Verhofstad, M H J

    2018-03-01

    One of the most challenging musculoskeletal complications in modern trauma surgery is infection after fracture fixation (IAFF). Although infections are clinically obvious in many cases, a clear definition of the term IAFF is crucial, not only for the evaluation of published research data but also for the establishment of uniform treatment concepts. The aim of this systematic review was to identify the definitions used in the scientific literature to describe infectious complications after internal fixation of fractures. The hypothesis of this study was that the majority of fracture-related literature do not define IAFF. A comprehensive search was performed in Embase, Cochrane, Google Scholar, Medline (OvidSP), PubMed publisher and Web-of-Science for randomized controlled trials (RCTs) on fracture fixation. Data were collected on the definition of infectious complications after fracture fixation used in each study. Study selection was accomplished through two phases. During the first phase, titles and abstracts were reviewed for relevance, and the full texts of relevant articles were obtained. During the second phase, full-text articles were reviewed. All definitions were literally extracted and collected in a database. Then, a classification was designed to rate the quality of the description of IAFF. A total of 100 RCT's were identified in the search. Of 100 studies, only two (2%) cited a validated definition to describe IAFF. In 28 (28%) RCTs, the authors used a self-designed definition. In the other 70 RCTs, (70%) there was no description of a definition in the Methods section, although all of the articles described infections as an outcome parameter in the Results section. This systematic review shows that IAFF is not defined in a large majority of the fracture-related literature. To our knowledge, this is the first study conducted with the objective to explore this important issue. The lack of a consensus definition remains a problem in current orthopedic trauma research and treatment and this void should be addressed in the near future. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. A Longitudinal Assessment of Sleep Timing, Circadian Phase, and Phase Angle of Entrainment across Human Adolescence

    PubMed Central

    Crowley, Stephanie J.; Van Reen, Eliza; LeBourgeois, Monique K.; Acebo, Christine; Tarokh, Leila; Seifer, Ronald; Barker, David H.; Carskadon, Mary A.

    2014-01-01

    The aim of this descriptive analysis was to examine sleep timing, circadian phase, and phase angle of entrainment across adolescence in a longitudinal study design. Ninety-four adolescents participated; 38 (21 boys) were 9–10 years (“younger cohort”) and 56 (30 boys) were 15–16 years (“older cohort”) at the baseline assessment. Participants completed a baseline and then follow-up assessments approximately every six months for 2.5 years. At each assessment, participants wore a wrist actigraph for at least one week at home to measure self-selected sleep timing before salivary dim light melatonin onset (DLMO) phase – a marker of the circadian timing system – was measured in the laboratory. Weekday and weekend sleep onset and offset and weekend-weekday differences were derived from actigraphy. Phase angles were the time durations from DLMO to weekday sleep onset and offset times. Each cohort showed later sleep onset (weekend and weekday), later weekend sleep offset, and later DLMO with age. Weekday sleep offset shifted earlier with age in the younger cohort and later in the older cohort after age 17. Weekend-weekday sleep offset differences increased with age in the younger cohort and decreased in the older cohort after age 17. DLMO to sleep offset phase angle narrowed with age in the younger cohort and became broader in the older cohort. The older cohort had a wider sleep onset phase angle compared to the younger cohort; however, an age-related phase angle increase was seen in the younger cohort only. Individual differences were seen in these developmental trajectories. This descriptive study indicated that circadian phase and self-selected sleep delayed across adolescence, though school-day sleep offset advanced until no longer in high school, whereupon offset was later. Phase angle changes are described as an interaction of developmental changes in sleep regulation interacting with psychosocial factors (e.g., bedtime autonomy). PMID:25380248

  17. A Descriptive Analysis of Tactical Casualty Care Interventions Performed by Law Enforcement Personnel in the State of Wisconsin, 2010-2015.

    PubMed

    Stiles, Chad M; Cook, Christopher; Sztajnkrycer, Matthew D

    2017-06-01

    Introduction Based upon military experience, law enforcement has developed guidelines for medical care during high-threat conditions. The purpose of the current study was to provide a descriptive analysis of reported outcomes of law enforcement medical interventions. This was a descriptive analysis of a convenience sample of cases submitted to the Wisconsin Tactical Medicine Initiative (Wisconsin USA), after the provision of successful patient care, between January 2010 and December 2015. The study was reviewed by the Mayo Foundation Institutional Review Board (Rochester, Minnesota USA) and deemed exempt. Nineteen agencies submitted information during the study period. Of the 56 episodes of care reported, four (7.1%) cases involved care provided to injured officers while 52 (92.9%) involved care to injured civilians, including suspects. In at least two cases, on-going threats existed during the provision of medical care to an injured civilian. Law enforcement rendered care prior to Emergency Medical Services (EMS) arrival in all but two cases. The current case series demonstrates the life-saving potential for law enforcement personnel trained and equipped under current Tactical Combat Casualty Care (TCCC)/ Committee on Tactical Emergency Casualty Care (C-TECC) tactical casualty care guidelines. Although originally developed to save the lives of wounded combat personnel, in the civilian sector, the training appears more likely to save victims rather than law enforcement personnel. Stiles CM , Cook C , Sztajnkrycer MD . A descriptive analysis of tactical casualty care interventions performed by law enforcement personnel in the State of Wisconsin, 2010-2015. Prehosp Disaster Med. 2017;32(3):284-288.

  18. Pore-scale Evaluation of Immiscible Fluid Characteristics and Displacements: Comparison Between Ambient- and Supercritical-Condition Experimental Studies

    NASA Astrophysics Data System (ADS)

    Herring, A. L.; Wildenschild, D.; Andersson, L.; Harper, E.; Sheppard, A.

    2015-12-01

    The transport of immiscible fluids within porous media is a topic of great importance for a wide range of subsurface processes; e.g. oil recovery, geologic sequestration of CO2, gas-water mass transfer in the vadose zone, and remediation of non-aqueous phase liquids (NAPLs) from groundwater. In particular, the trapping and mobilization of nonwetting phase fluids (e.g. oil, CO2, gas, or NAPL in water-wet media) is of significant concern; and has been well documented to be a function of both wetting and nonwetting fluid properties, morphological characteristics of the porous medium, and system history. However, generalization of empirical trends and results for application between different fluid-fluid-medium systems requires careful consideration and characterization of the relevant system properties. We present a comprehensive and cohesive description of nonwetting phase behaviour as observed via a suite of three dimensional x-ray microtomography imaging experiments investigating immiscible fluid flow, trapping, and interfacial interactions of wetting (brine) and nonwetting (air, oil, and supercritical CO2) phase in sandstones and synthetic media. Microtomographic images, acquired for drainage and imbibition flow processes, allow for precise and extensive characterization of nonwetting phase fluid saturation, topology, and connectivity; imaging results are paired with externally measured capillary pressure data to provide a comprehensive description of fluid states. Fluid flow and nonwetting phase trapping behaviour is investigated as a function of system history, morphological metrics of the geologic media, and nonwetting phase fluid characteristics; and particular emphasis is devoted to the differences between ambient condition (air-brine) and reservoir condition (supercritical CO2-brine) studies. Preliminary results provide insight into the applicability of using ambient condition experiments to explore reservoir condition processes, and also elucidate the underlying physics of trapping and mobilization of nonwetting phase fluids.

  19. Terahertz disorder-localized rotational modes and lattice vibrational modes in the orientationally-disordered and ordered phases of camphor.

    PubMed

    Nickel, Daniel V; Ruggiero, Michael T; Korter, Timothy M; Mittleman, Daniel M

    2015-03-14

    The temperature-dependent terahertz spectra of the partially-disordered and ordered phases of camphor (C10H16O) are measured using terahertz time-domain spectroscopy. In its partially-disordered phases, a low-intensity, extremely broad resonance is found and is characterized using both a phenomenological approach and an approach based on ab initio solid-state DFT simulations. These two descriptions are consistent and stem from the same molecular origin for the broad resonance: the disorder-localized rotational correlations of the camphor molecules. In its completely ordered phase(s), multiple lattice phonon modes are measured and are found to be consistent with those predicted using solid-state DFT simulations.

  20. Phase Coexistence in Insect Swarms

    NASA Astrophysics Data System (ADS)

    Sinhuber, Michael; Ouellette, Nicholas T.

    2017-10-01

    Animal aggregations are visually striking, and as such are popular examples of collective behavior in the natural world. Quantitatively demonstrating the collective nature of such groups, however, remains surprisingly difficult. Inspired by thermodynamics, we applied topological data analysis to laboratory insect swarms and found evidence for emergent, material-like states. We show that the swarms consist of a core "condensed" phase surrounded by a dilute "vapor" phase. These two phases coexist in equilibrium, and maintain their distinct macroscopic properties even though individual insects pass freely between them. We further define a pressure and chemical potential to describe these phases, extending theories of active matter to aggregations of macroscopic animals and laying the groundwork for a thermodynamic description of collective animal groups.

  1. Two-phase turbine engines. [using gas-liquid mixture accelerated in nozzles

    NASA Technical Reports Server (NTRS)

    Elliott, D. G.; Hays, L. G.

    1976-01-01

    A description is given of a two-phase turbine which utilizes a uniform mixture of gas and liquid accelerated in nozzles of the types reported by Elliott and Weinberg (1968). The mixture acts directly on an axial flow or tangential impulse turbine or is separated into gas and liquid streams which operate separately on a gas turbine and a hydraulic turbine. The basic two-phase cycles are examined, taking into account working fluids, aspects of nozzle expansion, details of turbine cycle operation, and the effect of mixture ratio variation. Attention is also given to two-phase nozzle efficiency, two-phase turbine operating characteristics and efficiencies, separator turbines, and impulse turbine experiments.

  2. Atmosphere, Magnetosphere and Plasmas in Space (AMPS). Spacelab payload definition study. Volume 7, book 2: AMPS phase C/D analysis and planning document

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The results are presented of the AMPS Phase C/D (Design, Development, and Operations) program analysis and planning effort. Cost and schedule estimates are included. Although the AMPS program has been specifically addressed, these task descriptions are basically adaptable to a broader-based program incorporating additional or different Spacelab/orbiter payloads.

  3. Kindergarten Teachers' Perceptions of the Relationship between Oral Language and Reading Achievement of Kindergarten Students and the Impact of State Standards and Educational Policy

    ERIC Educational Resources Information Center

    Costantino-Lane, Tina

    2013-01-01

    This mixed-method phenomenological study was conducted in 2 concurrent phases. The quantitative phase consisted of a researcher designed questionnaire conducted with 103 public school kindergarten teachers in California. Thirty-five close-ended and 2 open-ended questions were included. Descriptive and inferential statistics were utilized to find…

  4. Design Recovery for Software Library Population

    DTIC Science & Technology

    1992-12-01

    increase understandability, efficiency, and maintainability of the software and the design. A good representation choice will also aid in...required for a reengineering project. It details the analysis and planning phase and gives good criteria for determining the need for a reengineering...because it deals with all of these issues. With his complete description of the analysis and planning phase, Byrne has a good foundation for

  5. An investigation of wing buffeting response at subsonic and transonic speeds. Phase 2: F-111A flight data analysis. Volume 2: Plotted power spectra

    NASA Technical Reports Server (NTRS)

    Benepe, D. B.; Cunningham, A. M., Jr.; Traylor, S., Jr.; Dunmyer, W. D.

    1978-01-01

    Plotted power spectra for all of the flight points examined during the Phase 2 flight data analysis are presented. Detailed descriptions of the aircraft, the flight instrumentation and the analysis techniques are given. Measured and calculated vibration mode frequencies are also presented to assist in further interpretation of the PSD data.

  6. On The Validity of the Assumed PDF Method for Modeling Binary Mixing/Reaction of Evaporated Vapor in GAS/Liquid-Droplet Turbulent Shear Flow

    NASA Technical Reports Server (NTRS)

    Miller, R. S.; Bellan, J.

    1997-01-01

    An Investigation of the statistical description of binary mixing and/or reaction between a carrier gas and an evaporated vapor species in two-phase gas-liquid turbulent flows is perfomed through both theroetical analysis and comparisons with results from direct numerical simulations (DNS) of a two-phase mixing layer.

  7. Fourth ventricle neurocysticercosis: Rigid endoscopic management. Description of direct transcerebellar approach

    PubMed Central

    Ceja-Espinosa, A.; Franco-Jiménez, J. A.; Sosa-Nájera, A.; Gutiérrez-Aceves, G. A.; Ruiz-Flores, M. I.

    2017-01-01

    Background: Endoscopy has gained a crucial role in high specialty neurosurgery during the last decades. At present, there are well-defined flexible neuroendoscopic procedures to treat ventricular and subarachnoid space pathologies. Neurocysticercosis is recognized as a common cause of neurologic disease in developing countries and the United States. Surgical intervention, especially cerebrospinal fluid diversion, is the key for management of hydrocephalus. In 2002, a consensus suggested that ventricular forms should be treated with endoscopy as the first option. Case Description: Here, we present the case of a 51-year-old right-handed male, from Estado de México. Two days before admission he experienced holocraneal headache 7/10 on the visual analogue scale which was intermittent, with no response to any medication, sudden worsening of pain to 10/10, nausea, and vomit. On physical examination, he presented with 14 points in the Glasgow coma scale (M6, O4, V4), pupils were 3 mm, there was adequate light-reflex response, and bilateral papilledema. The cranial nerves did not have other pathological responses, extremities had adequate strength of 5/5, and normal reflexes (++/++) were noted. Neuroimaging studies showed dilatation of the four ventricles as well as a cystic lesion in the fourth ventricle. Surgical position was Concorde, and the approach through a suboccipital burr hole was planned preoperatively with craneometric points. A rigid Karl Storz Hopkins II® endoscope was inserted directly through the cerebellum and the cystic lesion was extracted entirely. Conclusion: This article presents a useful technique with low morbidity and mortality. Further investigation is needed, especially in our Mexico, where neuroendoscopical techniques are still in the development phase. PMID:29026668

  8. Rocketdyne Safety Algorithm: Space Shuttle Main Engine Fault Detection

    NASA Technical Reports Server (NTRS)

    Norman, Arnold M., Jr.

    1994-01-01

    The Rocketdyne Safety Algorithm (RSA) has been developed to the point of use on the TTBE at MSFC on Task 4 of LeRC contract NAS3-25884. This document contains a description of the work performed, the results of the nominal test of the major anomaly test cases and a table of the resulting cutoff times, a plot of the RSA value vs. time for each anomaly case, a logic flow description of the algorithm, the algorithm code, and a development plan for future efforts.

  9. Radiation from quantum weakly dynamical horizons in loop quantum gravity.

    PubMed

    Pranzetti, Daniele

    2012-07-06

    We provide a statistical mechanical analysis of quantum horizons near equilibrium in the grand canonical ensemble. By matching the description of the nonequilibrium phase in terms of weakly dynamical horizons with a local statistical framework, we implement loop quantum gravity dynamics near the boundary. The resulting radiation process provides a quantum gravity description of the horizon evaporation. For large black holes, the spectrum we derive presents a discrete structure which could be potentially observable.

  10. Liquid crystalline phase behavior in systems of hard-sphere chains

    NASA Astrophysics Data System (ADS)

    Williamson, Dave C.; Jackson, George

    1998-06-01

    A study of the liquid crystalline phase transitions in a system of hard-sphere chains is presented. The chains comprise m=7 tangentially bonded hard-sphere segments in a linear conformation (LHSC). The isothermal-isobaric Monte Carlo simulation technique is used to obtain the equation of state of the system both by compressing the isotropic (I) liquid and by expanding the solid (K). As well as the usual isotropic and solid phases, nematic and smectic-A liquid crystalline states are seen. A large degree of hysteresis is found in the neighborhood of the I-N transition. The results for the rigid LHSC system were compared with existing data for the corresponding semiflexible hard-sphere chains (FHSC): the flexibility has a large destabilizing effect on the nematic phase and consequently it postpones the I-N transition. The results of the simulations are also compared with rescaled Onsager theories for the I-N transition. It is rather surprising to find that the Parsons approach, which has been so successful for other hard-core models such as spherocylinders and ellipsoids, gives very poor results. The related approach of Vega and Lago gives a good description of the I-N phase transition. The procedure of Vega and Lago, as with all two-body resummations of the Onsager theory, only gives a qualitative description of the nematic order.

  11. Detailed validation of the bidirectional effect in various Case I and Case II waters.

    PubMed

    Gleason, Arthur C R; Voss, Kenneth J; Gordon, Howard R; Twardowski, Michael; Sullivan, James; Trees, Charles; Weidemann, Alan; Berthon, Jean-François; Clark, Dennis; Lee, Zhong-Ping

    2012-03-26

    Simulated bidirectional reflectance distribution functions (BRDF) were compared with measurements made just beneath the water's surface. In Case I water, the set of simulations that varied the particle scattering phase function depending on chlorophyll concentration agreed more closely with the data than other models. In Case II water, however, the simulations using fixed phase functions agreed well with the data and were nearly indistinguishable from each other, on average. The results suggest that BRDF corrections in Case II water are feasible using single, average, particle scattering phase functions, but that the existing approach using variable particle scattering phase functions is still warranted in Case I water.

  12. Fostering Entrepreneurship through Business Incubation: The Role and Prospects of Postsecondary Vocational-Technical Education. Report 2: Case Studies.

    ERIC Educational Resources Information Center

    Hernandez-Gantes, Victor M.; And Others

    This report presents nine case studies featuring efforts to foster community development through business incubation and entrepreneurial programs at two-year colleges. A background section discusses case description, and organization and format of case studies. The second section describes the case study design. Each case study is introduced with…

  13. Reconstruction of phase maps from the configuration of phase singularities in two-dimensional manifolds.

    PubMed

    Herlin, Antoine; Jacquemet, Vincent

    2012-05-01

    Phase singularity analysis provides a quantitative description of spiral wave patterns observed in chemical or biological excitable media. The configuration of phase singularities (locations and directions of rotation) is easily derived from phase maps in two-dimensional manifolds. The question arises whether one can construct a phase map with a given configuration of phase singularities. The existence of such a phase map is guaranteed provided that the phase singularity configuration satisfies a certain constraint associated with the topology of the supporting medium. This paper presents a constructive mathematical approach to numerically solve this problem in the plane and on the sphere as well as in more general geometries relevant to atrial anatomy including holes and a septal wall. This tool can notably be used to create initial conditions with a controllable spiral wave configuration for cardiac propagation models and thus help in the design of computer experiments in atrial electrophysiology.

  14. Comprehensive modeling of a liquid rocket combustion chamber

    NASA Technical Reports Server (NTRS)

    Liang, P.-Y.; Fisher, S.; Chang, Y. M.

    1985-01-01

    An analytical model for the simulation of detailed three-phase combustion flows inside a liquid rocket combustion chamber is presented. The three phases involved are: a multispecies gaseous phase, an incompressible liquid phase, and a particulate droplet phase. The gas and liquid phases are continuum described in an Eulerian fashion. A two-phase solution capability for these continuum media is obtained through a marriage of the Implicit Continuous Eulerian (ICE) technique and the fractional Volume of Fluid (VOF) free surface description method. On the other hand, the particulate phase is given a discrete treatment and described in a Lagrangian fashion. All three phases are hence treated rigorously. Semi-empirical physical models are used to describe all interphase coupling terms as well as the chemistry among gaseous components. Sample calculations using the model are given. The results show promising application to truly comprehensive modeling of complex liquid-fueled engine systems.

  15. A new experimental method to determine the sorption isotherm of a liquid in a porous medium.

    PubMed

    Ouoba, Samuel; Cherblanc, Fabien; Cousin, Bruno; Bénet, Jean-Claude

    2010-08-01

    Sorption from the vapor phase is an important factor controlling the transport of volatile organic compounds (VOCs) in the vadose zone. Therefore, an accurate description of sorption behavior is essential to predict the ultimate fate of contaminants. Several measurement techniques are available in the case of water, however, when dealing with VOCs, the determination of sorption characteristics generally relies on gas chromatography. To avoid some drawbacks associated with this technology, we propose a new method to determine the sorption isotherm of any liquid compounds adsorbed in a soil. This method is based on standard and costless transducers (gas pressure, temperature) leading to a simple and transportable experimental device. A numerical estimation underlines the good accuracy and this technique is validated on two examples. Finally, this method is applied to determine the sorption isotherm of three liquid compounds (water, heptane, and trichloroethylene) in a clayey soil.

  16. Analytical solutions for coagulation and condensation kinetics of composite particles

    NASA Astrophysics Data System (ADS)

    Piskunov, Vladimir N.

    2013-04-01

    The processes of composite particles formation consisting of a mixture of different materials are essential for many practical problems: for analysis of the consequences of accidental releases in atmosphere; for simulation of precipitation formation in clouds; for description of multi-phase processes in chemical reactors and industrial facilities. Computer codes developed for numerical simulation of these processes require optimization of computational methods and verification of numerical programs. Kinetic equations of composite particle formation are given in this work in a concise form (impurity integrated). Coagulation, condensation and external sources associated with nucleation are taken into account. Analytical solutions were obtained in a number of model cases. The general laws for fraction redistribution of impurities were defined. The results can be applied to develop numerical algorithms considerably reducing the simulation effort, as well as to verify the numerical programs for calculation of the formation kinetics of composite particles in the problems of practical importance.

  17. Programmable Self-assembly of Hydrocarbon-capped Nanoparticles: Role of Chain Conformations

    NASA Astrophysics Data System (ADS)

    Waltmann, Curt; Horst, Nathan; Travesset, Alex

    Nanoparticle superlattices (NPS), i.e. crystalline arrangements of nanoparticles, are materials with fascinating structures, which in many cases are not possible to attain from simple atoms or molecules. They also span a wide range of possible applications such as metamaterials, new energy sources, catalysis, and many others. In this talk, we present a theoretical and computational description of the self-assembly of nanoparticles with hydrocarbons as capping ligands. Usually, these systems have been described with hard sphere packing models. In this talk, we show that the conformations of the hydrocarbon chains play a fundamental role in determining the equilibrium phases, including and especially in binary systems. The work of CW was supported by a DOE-SULI internship from May-December 2016, and by NSF, DMR-CMMT 1606336 CDS&E: Design Principles for Ordering Nanoparticles into Super-crystals after January 1st.

  18. Removal of central obscuration and spider arm effects with beam-shaping coronagraphy

    NASA Astrophysics Data System (ADS)

    Abe, L.; Murakami, N.; Nishikawa, J.; Tamura, M.

    2006-05-01

    This paper describes a method for removing the effect of a centrally obscured aperture with additional spider arms in arbitrary geometrical configurations. The proposed method is based on a two-stage process where the light beam is first shaped to remove the central obscuration and spider arms, in order to feed a second, highly efficient coronagraph. The beam-shaping stage is a combination of a diffraction mask in the first focal plane and a complex amplitude filter located in the conjugate pupil. This paper specifically describes the case of using Lyot occulting masks and circular phase-shifting masks as diffracting components. The basic principle of the method is given along with an analytical description and numerical simulations. Substantial improvement in the performance of high-contrast coronagraphs can be obtained with this method, even if the beam-shaping filter is not perfectly manufactured.

  19. Investigation the evaporation-condensation problem by means of the joint numerical solution of the Boltzmann kinetic equation and interface modelling

    NASA Astrophysics Data System (ADS)

    Shiskova, I. N.; Kryukov, A. P.; Levashov, V. Yu

    2017-11-01

    The paper is devoted to research of the heat and mass transfer processes in liquid and vapor phase on the basis of the uniform approach assuming the through description of liquid, interface and vapor. Multiparticles interactions in liquid will be taken into account. The problem is studied when temperature in the depth of liquid differs from temperature in the vapor region. In this case there are both mass flux and heat flux. The study of influence of the correlations resulting from interactions of molecules set in thin near-surface liquid layers and an interface on intensity of evaporation is made. As a result of calculations the equilibrium line of the liquid-vapor saturation is obtained, which corresponds good enough with experimental data. Distributions of density, temperature, pressure, heat and mass fluxes, both in a liquid and in vapor are also presented.

  20. An exploration of function analysis and function allocation in the commercial flight domain

    NASA Technical Reports Server (NTRS)

    Mcguire, James C.; Zich, John A.; Goins, Richard T.; Erickson, Jeffery B.; Dwyer, John P.; Cody, William J.; Rouse, William B.

    1991-01-01

    The applicability is explored of functional analysis methods to support cockpit design. Specifically, alternative techniques are studied for ensuring an effective division of responsibility between the flight crew and automation. A functional decomposition is performed of the commercial flight domain to provide the information necessary to support allocation decisions and demonstrate methodology for allocating functions to flight crew or to automation. The function analysis employed 'bottom up' and 'top down' analyses and demonstrated the comparability of identified functions, using the 'lift off' segment of the 'take off' phase as a test case. The normal flight mission and selected contingencies were addressed. Two alternative methods for using the functional description in the allocation of functions between man and machine were investigated. The two methods were compared in order to ascertain their relative strengths and weaknesses. Finally, conclusions were drawn regarding the practical utility of function analysis methods.

  1. Equatorial radar system

    NASA Technical Reports Server (NTRS)

    Rukao, S.; Tsuda, T.; Sato, T.; Kato, S.

    1989-01-01

    A large clear air radar with the sensitivity of an incoherent scatter radar for observing the whole equatorial atmosphere up to 1000 km altitude is now being designed in Japan. The radar, called the Equatorial Radar, will be built in Pontianak, Kalimantan Island, Indonesia (0.03 N, 109.3 E). The system is a 47 MHz monostatic Doppler radar with an active phased array configuration similar to that of the MU radar in Japan, which has been in successful operation since 1983. It will have a PA product of more than 5 x 10(9) sq. Wm (P = average transmitter power, A = effective antenna aperture) with sensitivity more than 10 times that of the MU radar. This system configuration enables pulse-to-pulse beam steering within 25 deg from the zenith. As is the case of the MU radar, a variety of sophisticated operations will be made feasible under the supervision of the radar controller. A brief description of the system configuration is presented.

  2. Using peer-mediated instruction to support communication involving a student with autism during mathematics activities: A case study.

    PubMed

    Tan, Paulo; Alant, Erna

    2018-01-01

    This study employed an A-B singled subject design to explore the extent to which a peer-mediated intervention supported a first-grade student with autism's usage both in purpose and frequency of a speech-generating device (SGD) during mathematics activities. The intervention involved teaching a peer without a disability to encourage the student with autism to use the SGD during partnered mathematics activities. Our analysis involved visual and descriptive examination of trends and patterns over time, and comparison of means between and within phases. We found during the course of this study that (1) the student with autism's level of overall communication, which included the relevancy of these communicative behaviors, increased; (2) the student with autism's level of spontaneous communication acts increased; and (3) the peer became more independent with supporting the student with autism's communication. Implications for future research and practice are provided.

  3. The Harmony of Physics, Mathematics, and Music: A discovery in mathematical music theory is found to apply in physics

    NASA Astrophysics Data System (ADS)

    Krantz, Richard; Douthett, Jack

    2009-05-01

    Although it is common practice to borrow tools from mathematics to apply to physics or music, it is unusual to use tools developed in music theory to mathematically describe physical phenomena. So called ``Maximally Even Set'' theory fits this unusual case. In this poster, we summarize, by example, the theory of Maximally Even (ME) sets and show how this formalism leads to the distribution of black and white keys on the piano keyboard. We then show how ME sets lead to a generalization of the well-known ``Cycle-of-Fifths'' in music theory. Subsequently, we describe ordering in one-dimensional spin-1/2 anti-ferromagnets using ME sets showing that this description leads to a fractal ``Devil's Staircase'' magnetic phase diagram. Finally, we examine an extension of ME sets, ``Iterated Maximally Even Sets'' that describes chord structure in music.

  4. The Harmony of Physics, Mathematics, and Music: A discovery in mathematical music theory is found to apply in physics

    NASA Astrophysics Data System (ADS)

    Krantz, Richard; Douthett, Jack

    2009-10-01

    Although it is common practice to borrow tools from mathematics to apply to physics or music, it is unusual to use tools developed in music theory to mathematically describe physical phenomena. So called ``Maximally Even Set'' theory fits this unusual case. In this poster, we summarize, by example, the theory of Maximally Even (ME) sets and show how this formalism leads to the distribution of black and white keys on the piano keyboard. We then show how ME sets lead to a generalization of the well-known ``Cycle-of-Fifths'' in music theory. Subsequently, we describe ordering in one-dimensional spin-1/2 anti-ferromagnets using ME sets showing that this description leads to a fractal ``Devil's Staircase'' magnetic phase diagram. Finally, we examine an extension of ME sets, ``Iterated Maximally Even'' sets that describes chord structure in music.

  5. Fluidized bed combustor modeling

    NASA Technical Reports Server (NTRS)

    Horio, M.; Rengarajan, P.; Krishnan, R.; Wen, C. Y.

    1977-01-01

    A general mathematical model for the prediction of performance of a fluidized bed coal combustor (FBC) is developed. The basic elements of the model consist of: (1) hydrodynamics of gas and solids in the combustor; (2) description of gas and solids contacting pattern; (3) kinetics of combustion; and (4) absorption of SO2 by limestone in the bed. The model is capable of calculating the combustion efficiency, axial bed temperature profile, carbon hold-up in the bed, oxygen and SO2 concentrations in the bubble and emulsion phases, sulfur retention efficiency and particulate carry over by elutriation. The effects of bed geometry, excess air, location of heat transfer coils in the bed, calcium to sulfur ratio in the feeds, etc. are examined. The calculated results are compared with experimental data. Agreement between the calculated results and the observed data are satisfactory in most cases. Recommendations to enhance the accuracy of prediction of the model are suggested.

  6. Multi-frequency tapping-mode atomic force microscopy beyond three eigenmodes in ambient air

    PubMed Central

    An, Sangmin; Long, Christian J

    2014-01-01

    Summary We present an exploratory study of multimodal tapping-mode atomic force microscopy driving more than three cantilever eigenmodes. We present tetramodal (4-eigenmode) imaging experiments conducted on a thin polytetrafluoroethylene (PTFE) film and computational simulations of pentamodal (5-eigenmode) cantilever dynamics and spectroscopy, focusing on the case of large amplitude ratios between the fundamental eigenmode and the higher eigenmodes. We discuss the dynamic complexities of the tip response in time and frequency space, as well as the average amplitude and phase response. We also illustrate typical images and spectroscopy curves and provide a very brief description of the observed contrast. Overall, our findings are promising in that they help to open the door to increasing sophistication and greater versatility in multi-frequency AFM through the incorporation of a larger number of driven eigenmodes, and in highlighting specific future research opportunities. PMID:25383276

  7. Case Studies.

    ERIC Educational Resources Information Center

    Emerson, Allen; And Others

    1994-01-01

    Three cases of use of collaborative learning techniques in the college classroom are described: a developmental mathematics course, a graduate-level writing project, and college science instruction. Each case includes description of specific class activities and assignments, results, and teacher concerns and comments. (MSE)

  8. Slave finite element for non-linear analysis of engine structures. Volume 2: Programmer's manual and user's manual

    NASA Technical Reports Server (NTRS)

    Witkop, D. L.; Dale, B. J.; Gellin, S.

    1991-01-01

    The programming aspects of SFENES are described in the User's Manual. The information presented is provided for the installation programmer. It is sufficient to fully describe the general program logic and required peripheral storage. All element generated data is stored externally to reduce required memory allocation. A separate section is devoted to the description of these files thereby permitting the optimization of Input/Output (I/O) time through efficient buffer descriptions. Individual subroutine descriptions are presented along with the complete Fortran source listings. A short description of the major control, computation, and I/O phases is included to aid in obtaining an overall familiarity with the program's components. Finally, a discussion of the suggested overlay structure which allows the program to execute with a reasonable amount of memory allocation is presented.

  9. Collective effects in models for interacting molecular motors and motor-microtubule mixtures

    NASA Astrophysics Data System (ADS)

    Menon, Gautam I.

    2006-12-01

    Three problems in the statistical mechanics of models for an assembly of molecular motors interacting with cytoskeletal filaments are reviewed. First, a description of the hydrodynamical behaviour of density-density correlations in fluctuating ratchet models for interacting molecular motors is outlined. Numerical evidence indicates that the scaling properties of dynamical behaviour in such models belong to the KPZ universality class. Second, the generalization of such models to include boundary injection and removal of motors is provided. In common with known results for the asymmetric exclusion processes, simulations indicate that such models exhibit sharp boundary driven phase transitions in the thermodynamic limit. In the third part of this paper, recent progress towards a continuum description of pattern formation in mixtures of motors and microtubules is described, and a non-equilibrium “phase-diagram” for such systems discussed.

  10. Phases of five-dimensional theories, monopole walls, and melting crystals

    NASA Astrophysics Data System (ADS)

    Cherkis, Sergey A.

    2014-06-01

    Moduli spaces of doubly periodic monopoles, also called monopole walls or monowalls, are hyperkähler; thus, when four-dimensional, they are self-dual gravitational instantons. We find all monowalls with lowest number of moduli. Their moduli spaces can be identified, on the one hand, with Coulomb branches of five-dimensional supersymmetric quantum field theories on 3 × T 2 and, on the other hand, with moduli spaces of local Calabi-Yau metrics on the canonical bundle of a del Pezzo surface. We explore the asymptotic metric of these moduli spaces and compare our results with Seiberg's low energy description of the five-dimensional quantum theories. We also give a natural description of the phase structure of general monowall moduli spaces in terms of triangulations of Newton polygons, secondary polyhedra, and associahedral projections of secondary fans.

  11. Ordering phase transition in the one-dimensional Axelrod model

    NASA Astrophysics Data System (ADS)

    Vilone, D.; Vespignani, A.; Castellano, C.

    2002-12-01

    We study the one-dimensional behavior of a cellular automaton aimed at the description of the formation and evolution of cultural domains. The model exhibits a non-equilibrium transition between a phase with all the system sharing the same culture and a disordered phase of coexisting regions with different cultural features. Depending on the initial distribution of the disorder the transition occurs at different values of the model parameters. This phenomenology is qualitatively captured by a mean-field approach, which maps the dynamics into a multi-species reaction-diffusion problem.

  12. Review of Development Survey of Phase Change Material Models in Building Applications

    PubMed Central

    Akeiber, Hussein J.; Wahid, Mazlan A.; Hussen, Hasanen M.; Mohammad, Abdulrahman Th.

    2014-01-01

    The application of phase change materials (PCMs) in green buildings has been increasing rapidly. PCM applications in green buildings include several development models. This paper briefly surveys the recent research and development activities of PCM technology in building applications. Firstly, a basic description of phase change and their principles is provided; the classification and applications of PCMs are also included. Secondly, PCM models in buildings are reviewed and discussed according to the wall, roof, floor, and cooling systems. Finally, conclusions are presented based on the collected data. PMID:25313367

  13. Rocket injector anomalies study. Volume 1: Description of the mathematical model and solution procedure

    NASA Technical Reports Server (NTRS)

    Przekwas, A. J.; Singhal, A. K.; Tam, L. T.

    1984-01-01

    The capability of simulating three dimensional two phase reactive flows with combustion in the liquid fuelled rocket engines is demonstrated. This was accomplished by modifying an existing three dimensional computer program (REFLAN3D) with Eulerian Lagrangian approach to simulate two phase spray flow, evaporation and combustion. The modified code is referred as REFLAN3D-SPRAY. The mathematical formulation of the fluid flow, heat transfer, combustion and two phase flow interaction of the numerical solution procedure, boundary conditions and their treatment are described.

  14. Equilibrium Phase Behavior of a Continuous-Space Microphase Former.

    PubMed

    Zhuang, Yuan; Zhang, Kai; Charbonneau, Patrick

    2016-03-04

    Periodic microphases universally emerge in systems for which short-range interparticle attraction is frustrated by long-range repulsion. The morphological richness of these phases makes them desirable material targets, but our relatively coarse understanding of even simple models hinders controlling their assembly. We report here the solution of the equilibrium phase behavior of a microscopic microphase former through specialized Monte Carlo simulations. The results for cluster crystal, cylindrical, double gyroid, and lamellar ordering qualitatively agree with a Landau-type free energy description and reveal the nontrivial interplay between cluster, gel, and microphase formation.

  15. Effect of Coatings and Processing on Failure Mechanisms of Polycarbonate Material. Phase 1

    DTIC Science & Technology

    1991-11-01

    PHASE I By R.D. Eisler A.K. Chatterjee G. Burghart A.H. Koivu C.D. Newlander S.F. Stone Mission Research Corporation Costa Mesa, CA 92626 and...PHASE I ’ 6. AUTHOR(S) DAAK60-89- C-0011 R.D. EISLER , A.K. CHATTERJEE, G. BURGHART, A.H. KOIVU, C.D. NEWLANDER, S.F. STONE, E. HEALY* : 7...response to Department of Defense solicitation 88.1 dated 8 January 1987 , SBIR Topic ABB-140. The published description of SBIR topic A88-140 is included

  16. Computerized lateral-shear interferometer

    NASA Astrophysics Data System (ADS)

    Hasegan, Sorin A.; Jianu, Angela; Vlad, Valentin I.

    1998-07-01

    A lateral-shear interferometer, coupled with a computer for laser wavefront analysis, is described. A CCD camera is used to transfer the fringe images through a frame-grabber into a PC. 3D phase maps are obtained by fringe pattern processing using a new algorithm for direct spatial reconstruction of the optical phase. The program describes phase maps by Zernike polynomials yielding an analytical description of the wavefront aberration. A compact lateral-shear interferometer has been built using a laser diode as light source, a CCD camera and a rechargeable battery supply, which allows measurements in-situ, if necessary.

  17. A study of nonlinear dynamics of single- and two-phase flow oscillations

    NASA Astrophysics Data System (ADS)

    Mawasha, Phetolo Ruby

    The dynamics of single- and two-phase flows in channels can be contingent on nonlinearities which are not clearly understood. These nonlinearities could be interfacial forces between the flowing fluid and its walls, variations in fluid properties, growth of voids, etc. The understanding of nonlinear dynamics of fluid flow is critical in physical systems which can undergo undesirable system operating scenarios such an oscillatory behavior which may lead to component failure. A nonlinear lumped mathematical model of a surge tank with a constant inlet flow into the tank and an outlet flow through a channel is derived from first principles. The model is used to demonstrate that surge tanks with inlet and outlet flows contribute to oscillatory behavior in laminar, turbulent, single-phase, and two-phase flow systems. Some oscillations are underdamped while others are self-sustaining. The mechanisms that are active in single-phase oscillations with no heating are presented using specific cases of simplified models. Also, it is demonstrated how an external mechanism such as boiling contributes to the oscillations observed in two-phase flow and gives rise to sustained oscillations (or pressure drop oscillations). A description of the pressure drop oscillation mechanism is presented using the steady state pressure drop versus mass flow rate characteristic curve of the heated channel, available steady state pressure drop versus mass flow rate from the surge tank, and the transient pressure drop versus mass flow rate limit cycle. Parametric studies are used to verify the theoretical pressure drop oscillations model using experimental data by Yuncu's (1990). The following contributions are unique: (1) comparisons of nonlinear pressure drop oscillation models with and without the effect of the wall thermal heat capacity and (2) comparisons of linearized pressure drop oscillation models with and without the effect of the wall thermal heat capacity to identify stability boundaries.

  18. Molecular quantum control landscapes in von Neumann time-frequency phase space

    NASA Astrophysics Data System (ADS)

    Ruetzel, Stefan; Stolzenberger, Christoph; Fechner, Susanne; Dimler, Frank; Brixner, Tobias; Tannor, David J.

    2010-10-01

    Recently we introduced the von Neumann representation as a joint time-frequency description for femtosecond laser pulses and suggested its use as a basis for pulse shaping experiments. Here we use the von Neumann basis to represent multidimensional molecular control landscapes, providing insight into the molecular dynamics. We present three kinds of time-frequency phase space scanning procedures based on the von Neumann formalism: variation of intensity, time-frequency phase space position, and/or the relative phase of single subpulses. The shaped pulses produced are characterized via Fourier-transform spectral interferometry. Quantum control is demonstrated on the laser dye IR140 elucidating a time-frequency pump-dump mechanism.

  19. Molecular quantum control landscapes in von Neumann time-frequency phase space.

    PubMed

    Ruetzel, Stefan; Stolzenberger, Christoph; Fechner, Susanne; Dimler, Frank; Brixner, Tobias; Tannor, David J

    2010-10-28

    Recently we introduced the von Neumann representation as a joint time-frequency description for femtosecond laser pulses and suggested its use as a basis for pulse shaping experiments. Here we use the von Neumann basis to represent multidimensional molecular control landscapes, providing insight into the molecular dynamics. We present three kinds of time-frequency phase space scanning procedures based on the von Neumann formalism: variation of intensity, time-frequency phase space position, and/or the relative phase of single subpulses. The shaped pulses produced are characterized via Fourier-transform spectral interferometry. Quantum control is demonstrated on the laser dye IR140 elucidating a time-frequency pump-dump mechanism.

  20. Langley's CSI evolutionary model: Phase O

    NASA Technical Reports Server (NTRS)

    Belvin, W. Keith; Elliott, Kenny B.; Horta, Lucas G.; Bailey, Jim P.; Bruner, Anne M.; Sulla, Jeffrey L.; Won, John; Ugoletti, Roberto M.

    1991-01-01

    A testbed for the development of Controls Structures Interaction (CSI) technology to improve space science platform pointing is described. The evolutionary nature of the testbed will permit the study of global line-of-sight pointing in phases 0 and 1, whereas, multipayload pointing systems will be studied beginning with phase 2. The design, capabilities, and typical dynamic behavior of the phase 0 version of the CSI evolutionary model (CEM) is documented for investigator both internal and external to NASA. The model description includes line-of-sight pointing measurement, testbed structure, actuators, sensors, and real time computers, as well as finite element and state space models of major components.

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