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Sample records for affect numerous aspects

  1. Affective and Cognitive Aspects of Bilingualism.

    ERIC Educational Resources Information Center

    Herrell, Ileana Collado; Herrell, James M.

    1980-01-01

    A study showing that lexically equivalent words in two languages have different affective meanings, that affective intensity of dominant language words is greater than for second language equivalents, and that the difference is greatest for words with high affective meaning demonstrates that affective meaning is an important component of…

  2. Numerical Investigation of Finite Aspect-Ratio Flapping Foils

    NASA Astrophysics Data System (ADS)

    Mittal, R.; Najjar, F.; Bozkurttas, M.

    2003-11-01

    Most wings and fins found in nature tend to be of low aspect-ratio. However, despite this preponderence of low aspect-ratio foils in nature, most experimental and numerical studies in this area of bio-hydrodynamics have focussed on examining infinite aspect-ratio flapping foils. Here we have used numerical simulations to investigate the flow associated with finite aspect-ratio foils. Particular focus of the study is on examining the effect of aspect-ratio on the thrust chracteristics and the wake topology of the foil. The simulations employ a newly developed Cartesian grid method which allows us to simulate flows with complex three-dimensional bodies on fixed Cartesian grids. The simulations indicate that the wake topology of these relatively low aspect-ratio foils is significantly different from that observed for infinite-aspect-ratio foils. The simulations also allow us to assess the advantage/disadvantage that the lower aspect ratio might confer on the performance of a flapping foil. Results from this study will be presented.

  3. STRUCTURAL AND AFFECTIVE ASPECTS OF CLASSROOM CLIMATE.

    ERIC Educational Resources Information Center

    WALBERG, HERBERT J.

    USING THE CLASSROOM AS THE UNIT OF ANALYSIS A 25 PERCENT RANDOM SAMPLE OF STUDENTS IN 72 CLASSES FROM ALL PARTS OF THE COUNTRY TOOK THE CLASSROOM CLIMATE QUESTIONNAIRE IN ORDER TO INVESTIGATE THE RELATIONSHIP BETWEEN STRUCTURAL (ORGANIZATIONAL) AND AFFECTIVE (PERSONAL INTERACTION BETWEEN GROUP MEMBERS) DIMENSIONS OF GROUP CLIMATE. REGRESSION AND…

  4. Numerical aspects of searching convective/absolute instability transition

    NASA Astrophysics Data System (ADS)

    Suslov, Sergey A.

    2006-02-01

    An overview of various numerical techniques used to determine the spatio-temporal character of instabilities in fluid flows is given. The advantageous features of various previously known individual techniques are discussed and a practical procedure combining them is suggested for a specific task of determining the complete boundary between linearly convectively and absolutely unstable regimes in a multi-parameter space in problems with a fully numerical dispersion relation. Special attention is paid to aspects of automatization of computations as this is a crucial condition for their efficiency. The suggested procedure is successfully used and is shown to provide a high degree of automatism in the physical example of non-Boussinesq mixed convection in a vertical channel. This example comprises most of the major numerical difficulties found in various spatio-temporal instability studies of two-dimensional fluid flows which previously could not be handled without frequent human intervention and visual inspection of intermediate results. This paper focuses on the general numerical aspects of the computations leaving the detailed discussion of the obtained physical results for a separate publication.

  5. Aspects of Manual Wheelchair Configuration Affecting Mobility: A Review

    PubMed Central

    Medola, Fausto Orsi; Elui, Valeria Meirelles Carril; Santana, Carla da Silva; Fortulan, Carlos Alberto

    2014-01-01

    Many aspects relating to equipment configuration affect users’ actions in a manual wheelchair, determining the overall mobility performance. Since the equipment components and configuration determine both stability and mobility efficiency, configuring the wheelchair with the most appropriate set-up for individual users’ needs is a difficult task. Several studies have shown the importance of seat/backrest assembly and the relative position of the rear wheels to the user in terms of the kinetics and kinematics of manual propulsion. More recently, new studies have brought to light evidence on the inertial properties of different wheelchair configurations. Further new studies have highlighted the handrim as a key component of wheelchair assembly, since it is the interface through which the user drives the chair. In light of the new evidence on wheelchair mechanics and propulsion kinetics and kinematics, this article presents a review of the most important aspects of wheelchair configuration that affect the users’ actions and mobility. PMID:24648656

  6. Teachers’ perceptions of aspects affecting seminar learning: a qualitative study

    PubMed Central

    2013-01-01

    Background Many medical schools have embraced small group learning methods in their undergraduate curricula. Given increasing financial constraints on universities, active learning groups like seminars (with 25 students a group) are gaining popularity. To enhance the understanding of seminar learning and to determine how seminar learning can be optimised it is important to investigate stakeholders’ views. In this study, we qualitatively explored the views of teachers on aspects affecting seminar learning. Methods Twenty-four teachers with experience in facilitating seminars in a three-year bachelor curriculum participated in semi-structured focus group interviews. Three focus groups met twice with an interval of two weeks led by one moderator. Sessions were audio taped, transcribed verbatim and independently coded by two researchers using thematic analysis. An iterative process of data reduction resulted in emerging aspects that influence seminar learning. Results Teachers identified seven key aspects affecting seminar learning: the seminar teacher, students, preparation, group functioning, seminar goals and content, course coherence and schedule and facilities. Important components of these aspects were: the teachers’ role in developing seminars (‘ownership’), the amount and quality of preparation materials, a non-threatening learning climate, continuity of group composition, suitability of subjects for seminar teaching, the number and quality of seminar questions, and alignment of different course activities. Conclusions The results of this study contribute to the unravelling of the ‘the black box’ of seminar learning. Suggestions for ways to optimise active learning in seminars are made regarding curriculum development, seminar content, quality assurance and faculty development. PMID:23399475

  7. Knowledge Engineering Aspects of Affective Bi-Modal Educational Applications

    NASA Astrophysics Data System (ADS)

    Alepis, Efthymios; Virvou, Maria; Kabassi, Katerina

    This paper analyses the knowledge and software engineering aspects of educational applications that provide affective bi-modal human-computer interaction. For this purpose, a system that provides affective interaction based on evidence from two different modes has been developed. More specifically, the system's inferences about students' emotions are based on user input evidence from the keyboard and the microphone. Evidence from these two modes is combined by a user modelling component that incorporates user stereotypes as well as a multi criteria decision making theory. The mechanism that integrates the inferences from the two modes has been based on the results of two empirical studies that were conducted in the context of knowledge engineering of the system. The evaluation of the developed system showed significant improvements in the recognition of the emotional states of users.

  8. Vortical flow aerodynamics - Physical aspects and numerical simulation

    NASA Technical Reports Server (NTRS)

    Newsome, Richard W.; Kandil, Osama A.

    1987-01-01

    Progress in the numerical simulation of vortical flow due to three-dimensional flow separation about flight vehicles at high angles of attack and quasi-steady flight conditions is surveyed. Primary emphasis is placed on Euler and Reynolds-averaged Navier-Stokes methods where the vortices are 'captured' as a solution to the governing equations. A discussion of the relevant flow physics provides a perspective from which to assess numerical solutions. Current numerical prediction capabilities and their evolutionary development are surveyed. Future trends and challenges are identified and discussed.

  9. Taking Perspective: Personal Pronouns Affect Experiential Aspects of Literary Reading.

    PubMed

    Hartung, Franziska; Burke, Michael; Hagoort, Peter; Willems, Roel M

    2016-01-01

    Personal pronouns have been shown to influence cognitive perspective taking during comprehension. Studies using single sentences found that 3rd person pronouns facilitate the construction of a mental model from an observer's perspective, whereas 2nd person pronouns support an actor's perspective. The direction of the effect for 1st person pronouns seems to depend on the situational context. In the present study, we investigated how personal pronouns influence discourse comprehension when people read fiction stories and if this has consequences for affective components like emotion during reading or appreciation of the story. We wanted to find out if personal pronouns affect immersion and arousal, as well as appreciation of fiction. In a natural reading paradigm, we measured electrodermal activity and story immersion, while participants read literary stories with 1st and 3rd person pronouns referring to the protagonist. In addition, participants rated and ranked the stories for appreciation. Our results show that stories with 1st person pronouns lead to higher immersion. Two factors-transportation into the story world and mental imagery during reading-in particular showed higher scores for 1st person as compared to 3rd person pronoun stories. In contrast, arousal as measured by electrodermal activity seemed tentatively higher for 3rd person pronoun stories. The two measures of appreciation were not affected by the pronoun manipulation. Our findings underscore the importance of perspective for language processing, and additionally show which aspects of the narrative experience are influenced by a change in perspective. PMID:27192060

  10. Taking Perspective: Personal Pronouns Affect Experiential Aspects of Literary Reading

    PubMed Central

    Burke, Michael; Hagoort, Peter; Willems, Roel M.

    2016-01-01

    Personal pronouns have been shown to influence cognitive perspective taking during comprehension. Studies using single sentences found that 3rd person pronouns facilitate the construction of a mental model from an observer’s perspective, whereas 2nd person pronouns support an actor’s perspective. The direction of the effect for 1st person pronouns seems to depend on the situational context. In the present study, we investigated how personal pronouns influence discourse comprehension when people read fiction stories and if this has consequences for affective components like emotion during reading or appreciation of the story. We wanted to find out if personal pronouns affect immersion and arousal, as well as appreciation of fiction. In a natural reading paradigm, we measured electrodermal activity and story immersion, while participants read literary stories with 1st and 3rd person pronouns referring to the protagonist. In addition, participants rated and ranked the stories for appreciation. Our results show that stories with 1st person pronouns lead to higher immersion. Two factors—transportation into the story world and mental imagery during reading—in particular showed higher scores for 1st person as compared to 3rd person pronoun stories. In contrast, arousal as measured by electrodermal activity seemed tentatively higher for 3rd person pronoun stories. The two measures of appreciation were not affected by the pronoun manipulation. Our findings underscore the importance of perspective for language processing, and additionally show which aspects of the narrative experience are influenced by a change in perspective. PMID:27192060

  11. Aspects of Numerical Simulation of Circulation Control Airfoils

    NASA Technical Reports Server (NTRS)

    Swanson, R. C.; Rumsey, C. L.; Anders, S. G.

    2005-01-01

    The mass-averaged compressible Navier-Stokes equations are solved for circulation control airfoils. Numerical solutions are computed with a multigrid method that uses an implicit approximate factorization smoother. The effects of flow conditions (e.g., free-stream Mach number, angle of attack, momentum coefficient) and mesh on the prediction of circulation control airfoil flows are considered. In addition, the impact of turbulence modeling, including curvature effects and modifications to reduce eddy viscosity levels in the wall jet (i.e., Coanda flow), is discussed. Computed pressure distributions are compared with available experimental data.

  12. Numerical aspects of spectral segmentation on polygonal grids

    SciTech Connect

    Matsekh, Anna; Skurikhin, Alexei; Prasad, Lakshman; Rosten, Edward

    2010-01-01

    The authors analyze numerical behavior of the spectral graph partitioning problem arising in the Normalized Cuts formulation of the image segmentation problem on polygonal grids. They make an observation that in the presence of rounding errors the eigenvector corresponding to the k-th smallest eigenvalue of the generalized graph Laplacian should contain more than k nodal domains that represent coherent segments in the image. As the result, the eigenvector corresponding to the trivial solution carries a wealth of information about the nodal domains in the image and can be used as an initial guess for the Krylov subspace eigensolver, while the computed eigenvector subspace, corresponding to just a few of the lowest eigenvalues of the graph Laplacian, will contain sufficient information for obtaining meaningful segmentation.

  13. [THE MANIC DEPRESSIVE DISEASE: PSYCHODYNAMICS ASPECTS AND AFFECTIVE SYNTONY].

    PubMed

    Widakowich, Christian

    2015-01-01

    In a time when manic-depressive disease became bipolar disorder, and it is conceptualized and treated almost as a fully medical illness, such as epilepsy, we found worth returning to some psychodynamic aspects underlying this condition. Conventionally, we depart from the concept of melancholy, to introduce in a second time, the mania, as a liberating solution of the depression. To Abraham (1912), mania is the liberation from suffering imposed by the reality principle For Freud (1915), mania becomes a leak from the ego face a tyrannical superego (the encounter of ego and the ego ideal). Klein (1934) explains that the mania serves to counter the depressive position and thus avoid the guilt inside of ego. For Racamier (1979), mania is clearly a frantic negation of the anguish and emotional suffering. Today, some authors as Chabot and Husain try to define the manic depression organization, with the help of projective tests. This personality structure would be between psychosis and borderline. An axial element of this structure is the research for an affective symbiosis with each other. These concept, strongly resemble the "syntony", from Bleuler. We trace the evolution of manic depression from a psychodynamic and structural point of view, with particular interesting in the concept of syntony. PMID:26323110

  14. Some aspects of powerplant airframe integration affecting fuel conservation

    NASA Technical Reports Server (NTRS)

    Farbridge, J. E.

    1978-01-01

    The performance criteria for STOL transport aircraft place many constraints on engineering design, which, in turn, may have a direct bearing on fuel efficiency: these constraints become even more severe with the introduction of powered-lift for turbofan aircraft. Consideration is given to some aspects of performance and design which arise as a result of powerplant/airframe integration and an attempt is made to assess these factors in terms of transport fuel efficiency. The drag polars of various powered lift concepts are analyzed to determine the installed thrust/weight required and a simple method of relating this to fuel efficiency is suggested. Some other factors have been identified as being important to this aspect of design and these are discussed in more general terms. Finally, special consideration is given to recent Canadian research in the realm of supercritical airfoil technology as applied to an multi-foil section which could be utilized both for the STOL regime of flight and for cruise at transonic speeds.

  15. Numerical studies of the reversed-field pinch at high aspect ratio

    NASA Astrophysics Data System (ADS)

    Sätherblom, H.-E.; Drake, J. R.

    1998-10-01

    The reversed field pinch (RFP) configuration at an aspect ratio of 8.8 is studied numerically by means of the three-dimensional magnetohydrodynamic code DEBS [D. D. Schnack et al., J. Comput. Phys. 70, 330 (1987)]. This aspect ratio is equal to that of the Extrap T1 experiment [S. Mazur et al., Nucl. Fusion 34, 427 (1994)]. A numerical study of a RFP with this level of aspect ratio requires extensive computer achievements and has hitherto not been performed. The results are compared with previous studies [Y. L. Ho et al., Phys. Plasmas 2, 3407 (1995)] of lower aspect ratio RFP configurations. In particular, an evaluation of the extrapolation to the aspect ratio of 8.8 made in this previous study shows that the extrapolation of the spectral spread, as well as most of the other findings, are confirmed. An important exception, however, is the magnetic diffusion coefficient, which is found to decrease with aspect ratio. Furthermore, an aspect ratio dependence of the magnetic energy and of the helicity of the RFP is found.

  16. New aspects on patients affected by dysferlin deficient muscular dystrophy

    PubMed Central

    Klinge, Lars; Aboumousa, Ahmed; Eagle, Michelle; Hudson, Judith; Sarkozy, Anna; Vita, Gianluca; Charlton, Richard; Roberts, Mark; Straub, Volker; Barresi, Rita; Lochmüller, Hanns

    2009-01-01

    Mutations in the dysferlin gene lead to limb girdle muscular dystrophy 2B, Miyoshi myopathy and distal anterior compartment myopathy. A cohort of 36 patients affected by dysferlinopathy is described, in the first UK study of clinical, genetic, pathological and biochemical data. The diagnosis was established by reduction of dysferlin in the muscle biopsy and subsequent mutational analysis of the dysferlin gene. Seventeen mutations were novel; the majority of mutations were small deletions/insertions, and no mutational hotspots were identified. Sixty-one per cent of patients (22 patients) initially presented with limb girdle muscular dystrophy 2B, 31% (11 patients) with a Miyoshi phenotype, one patient with proximodistal mode of onset, one patient with muscle stiffness after exercise and one patient as a symptomatic carrier. A wider range of age of onset was noted than previously reported, with 25% of patients having first symptoms before the age of 13 years. Independent of the initial mode of presentation, in our cohort of patients the gastrocnemius muscle was the most severely affected muscle leading to an inability to stand on tiptoes, and lower limbs were affected more severely than upper limbs. As previous anecdotal evidence on patients affected by dysferlinopathy suggests good muscle prowess before onset of symptoms, we also investigated pre-symptomatic fitness levels of the patients. Fifty-three per cent of the patients were very active and sporty before the onset of symptoms which makes the clinical course of dysferlinopathy unusual within the different forms of muscular dystrophy and provides a challenge to understanding the underlying pathomechanisms in this disease. PMID:19528035

  17. Morphopathological aspects of healthy nails and nails affected by onychomycosis.

    PubMed

    Zaikovska, Olga; Pilmane, Mara; Kisis, Janis

    2014-09-01

    Patients of onychomycosis are common in the dermatology practice. Contemporary morphology creates opportunities to study the functional units of the nail when such infections occur from morphopathological point of view. There were 22 nails biopsies from onychomycosis patients taken for the research of morphopathological changes in the thickened nail plate affected by onychomycosis. Samples of cadaverous' nails were used as a control material. The material was stained with haematoxylin and eosin and immunohistochemical methods. Terminal deoxynucleotidyl transferase dUTP nick end labelling reaction and periodic acid-Schiff reaction were also performed. We found patchy hypertrophy in the granulose layer of the epidermis, with focal acanthosis. In the horn layer, we identified nests of parakeratosis of various sizes, with incorporations of homogenous and eosinophil masses. We found high levels of interleukin 6 and interleukin 10 positive cells in the nail bed and in the bloodstream. Interleukin 1, however, was not a part of any of the functional units of any of the nails. Significant amount of fibres containing human beta defensin-2 were found in the bed and plate of the nail. Therefore one can conclude that as regards the nails affected by onychomycosis, the most effective morphopathogenical processes include cytokine and defensin excretion occurrence in the nail bed.

  18. Numerical Investigation of the Performance of Finite Aspect-Ratio Flapping Foils

    NASA Astrophysics Data System (ADS)

    Dong, Haibo; Mittal, Rajat; Bozkurttas, Meliha; Najjar, Fady

    2004-11-01

    Most wings and fins found in nature tend to be of low aspect-ratio. However, most experimental and numerical studies in this area of bio-hydrodynamics have focused on examining infinite aspect-ratio flapping foils. In the current study, an efficient finite-difference based solver for computing flows with moving immersed solid three-dimensional boundaries on fixed Cartesian grids has been developed. This solver has been used to explore the wake structure and the hydrodynamic performance of different kind of finite aspect-ratio flapping foils undergoing a combined pitch-and-heave motion. Simulations have been performed for different Reynolds numbers and different Strouhal numbers respectively. The Lagrangian dynamic SGS model is also employed for high Reynolds number cases. The simulations indicate that the wake topology of these relatively low aspect-ratio foils is significantly different from that observed for infinite-aspect-ratio foils. In particular, inverse Karman vortex street is not observed even at aspect-ratio 4.0. The implications of the wake topology on thrust performance are also examined in this study.

  19. The Fifth Symposium on Numerical and Physical Aspects of Aerodynamic Flows

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This volume contains the papers presented at the Fifth Symposium on Numerical and Physical Aspects of Aerodynamic Flows, held at the California State University, Long Beach, from 13 to 15 January 1992. The symposium, like its immediate predecessors, considers the calculation of flows of relevance to aircraft, ships, and missiles with emphasis on the solution of two-dimensional unsteady and three-dimensional equations.

  20. Numerical investigation of flow on NACA4412 aerofoil with different aspect ratios

    NASA Astrophysics Data System (ADS)

    Demir, Hacımurat; Özden, Mustafa; Genç, Mustafa Serdar; Çağdaş, Mücahit

    2016-03-01

    In this study, the flow over NACA4412 was investigated both numerically and experimentally at a different Reynolds numbers. The experiments were carried out in a low speed wind tunnel with various angles of attack and different Reynolds numbers (25000 and 50000). Airfoil was manufactured using 3D printer with a various aspect ratios (AR = 1 and AR = 3). Smoke-wire and oil flow visualization methods were used to visualize the surface flow patterns. NACA4412 aerofoil was designed by using SOLIDWORKS. The structural grid of numerical model was constructed by ANSYS ICEM CFD meshing software. Furthermore, ANSYS FLUENT™ software was used to perform numerical calculations. The numerical results were compared with experimental results. Bubble formation was shown in CFD streamlines and smoke-wire experiments at z / c = 0.4. Furthermore, bubble shrunk at z / c = 0.2 by reason of the effects of tip vortices in both numerical and experimental studies. Consequently, it was seen that there was a good agreement between numerical and experimental results.

  1. Some numerical aspects of the training problem for feed-forward neural nets.

    PubMed

    Hall, Gary; Stella, Fabio; J McKeown, John

    1997-11-01

    This paper considers the feed-forward training problem from the numerical point of view, in particular the conditioning of the problem. It is well known that the feed-forward training problem is often ill-conditioned; this affects the behaviour of training algorithms, the choice of such algorithms and the quality of the solutions achieved. A geometric interpretation of ill-conditioning is explored and an example of function approximation is analysed in detail.

  2. Numerical analysis of the turbulent fluid flow through valves. Geometrical aspects influence at different positions

    NASA Astrophysics Data System (ADS)

    Rigola, J.; Aljure, D.; Lehmkuhl, O.; Pérez-Segarra, C. D.; Oliva, A.

    2015-08-01

    The aim of this paper is to carry out a group of numerical experiments over the fluid flow through a valve reed, using the CFD&HT code TermoFluids, an unstructured and parallel object-oriented CFD code for accurate and reliable solving of industrial flows. Turbulent flow and its solution is a very complex problem due to there is a non-lineal interaction between viscous and inertial effects further complicated by their rotational nature, together with the three-dimensionality inherent in these types of flow and the non-steady state solutions. In this work, different meshes, geometrical conditions and LES turbulence models (WALE, VMS, QR and SIGMA) are tested and results compared. On the other hand, the fluid flow boundary conditions are obtained by means of the numerical simulation model of hermetic reciprocating compressors tool, NEST-compressor code. The numerical results presented are based on a specific geometry, where the valve gap opening percentage is 11% of hole diameter and Reynolds numbers given by the one-dimensional model is 4.22 × 105, with density meshes of approximately 8 million CVs. Geometrical aspects related with the orifice's shape and its influence on fluid flow behaviour and pressure drop are analysed in detail, furthermore, flow results for different valve openings are also studied.

  3. Understanding the Emotional Aspects of Escalation of Commitment: The Role of Negative Affect

    ERIC Educational Resources Information Center

    Wong, Kin Fai Ellick; Yik, Michelle; Kwong, Jessica Y. Y.

    2006-01-01

    Despite the importance of understanding the emotional aspects of organizational decision making, prior research has paid scant attention to the role of emotion in escalation of commitment. This article attempts to fill this gap by examining the relationship between negative affect and escalation of commitment. Results showed that regardless of…

  4. A numerical scheme and some theoretical aspects for the cylindrically and spherically symmetric sine-Gordon equations

    NASA Astrophysics Data System (ADS)

    Nguyen, Lu Trong Khiem

    2016-07-01

    A finite difference formula based on the predictor-corrector technique is presented to integrate the cylindrically and spherically symmetric sine-Gordon equations numerically. Based on various numerical observations, one property of the waves of kink type is conjectured and used to explain their returning effect. Several numerical experiments are carried out and they are in excellent agreement with the existing results. In addition, the corresponding modulation solution for the two-dimensional ring-shaped kink is extended to that in three-dimension. Both numerical and theoretical aspects are utilized to verify the reliability of the proposed numerical scheme and thus the analytical modulation solutions.

  5. Numerical simulation of the tip vortex off a low-aspect-ratio wing at transonic speed

    NASA Technical Reports Server (NTRS)

    Mansour, N. N.

    1984-01-01

    The viscous transonic flow around a low aspect ratio wing was computed by an implicit, three dimensional, thin-layer Navier-Stokes solver. The grid around the geometry of interest is obtained numerically as a solution to a Dirichlet problem for the cube. A low aspect ratio wing with large sweep, twist, taper, and camber is the chosen geometry. The topology chosen to wrap the mesh around the wing with good tip resolution is a C-O type mesh. The flow around the wing was computed for a free stream Mach number of 0.82 at an angle of attack of 5 deg. At this Mach number, an oblique shock forms on the upper surface of the wing, and a tip vortex and three dimensional flow separation off the wind surface are observed. Particle path lines indicate that the three dimensional flow separation on the wing surface is part of the roots of the tip vortex formation. The lifting of the tip vortex before the wing trailing edge is observed by following the trajectory of particles release around the wing tip.

  6. Numerical simulation of the tip vortex off a low-aspect-ratio wing at transonic speed

    NASA Technical Reports Server (NTRS)

    Mansour, N. N.

    1984-01-01

    The viscous transonic flow around a low-aspect-ratio wing has been computed using an implicit, three-dimensional, 'thin-layer' Navier-Stokes solver. The grid around the geometry of interest is obtained numerically as a solution to a Dirichlet problem for the cube. The geometry chosen for this study is a low-aspect-ratio wing with large sweep, twist, taper, and camber. The topology chosen to wrap the mesh around the wing with good tip resolution is a C-O type mesh. Using this grid, the flow around the wing was computed for a free-stream Mach number of 0.82 at an angle of attack of 5 deg. At this Mach number, an oblique shock forms on the upper surface of the wing, and a tip vortex and three-dimensional flow separation off the wing surface are observed. Particle path lines indicate that the three-dimensional flow separation on the wing surface is part of the roots of the tip-vortex formation. The lifting of the tip vortex before the wing trailing edge is clearly observed by following the trajectory of particles released around the wing tip.

  7. An investigation of the information propagation and entropy transport aspects of Stirling machine numerical simulation

    NASA Technical Reports Server (NTRS)

    Goldberg, Louis F.

    1992-01-01

    Aspects of the information propagation modeling behavior of integral machine computer simulation programs are investigated in terms of a transmission line. In particular, the effects of pressure-linking and temporal integration algorithms on the amplitude ratio and phase angle predictions are compared against experimental and closed-form analytic data. It is concluded that the discretized, first order conservation balances may not be adequate for modeling information propagation effects at characteristic numbers less than about 24. An entropy transport equation suitable for generalized use in Stirling machine simulation is developed. The equation is evaluated by including it in a simulation of an incompressible oscillating flow apparatus designed to demonstrate the effect of flow oscillations on the enhancement of thermal diffusion. Numerical false diffusion is found to be a major factor inhibiting validation of the simulation predictions with experimental and closed-form analytic data. A generalized false diffusion correction algorithm is developed which allows the numerical results to match their analytic counterparts. Under these conditions, the simulation yields entropy predictions which satisfy Clausius' inequality.

  8. Impact of vegetation on stability of slopes subjected to rainfall - numerical aspect

    NASA Astrophysics Data System (ADS)

    Switala, Barbara Maria; Tamagnini, Roberto; Sudan Acharya, Madhu; Wu, Wei

    2015-04-01

    Recent years brought a significant development of soil bioengineering methods, considered as an ecological and economically effective measure for slope stabilization. This work aims to show the advantages of the soil bioengineering solutions for a slope subjected to a heavy rainfall, with the help of a numerical model, which integrates most of the significant plant and slope features. There are basically two different ways in which vegetation can affect stability of a slope: root reinforcement (mechanical impact) and root water uptake (evapotranspiration). In the numerical model, the first factor is modelled using the Cam-Clay model extended for unsaturated conditions by Tamagnini (2004). The original formulation of a constitutive model is modified by introducing an additional constitutive parameter, which causes an expansion of the yield surface as a consequence of an increase in root mass in a representative soil element. The second factor is the root water uptake, which is defined as a volumetric sink term in the continuity equation of groundwater flow. Water removal from the soil mass causes an increase in suction in the vicinity of the root zone, which leads to an increase in the soil cohesion and provides additional strength to the soil-root composite. The developed numerical model takes into account the above mentioned effects of plants and thus considers the multi-phase nature of the soil-plant-water relationship. Using the developed method, stability of some vegetated and non-vegetated slopes subjected to rainfall are investigated. The performance of each slope is evaluated by the time at which slope failure occurs. Different slope geometries and soil mechanical and hydrological properties are considered. Comparison of the results obtained from the analyses of vegetated and non-vegetated slopes leads to the conclusion, that the use of soil bioengineering methods for slope stabilization can be effective and can significantly delay the occurrence of a

  9. Unconscious Desire: The Affective and Motivational Aspects of Subliminal Sexual Priming.

    PubMed

    Gillath, Omri; Collins, Tara

    2016-01-01

    Sexual arousal is thought to be the result of the processing of sexual cues at two levels: conscious and unconscious. Whereas numerous studies have examined the affective and motivational responses to supraliminal (consciously processed) sexual cues, much less is known regarding the responses to subliminal (processed outside of one's awareness) sexual cues. Five studies examined responses to subliminal sexual cues. Studies 1–3 demonstrated increases in adults' positive affect following exposure to subliminal sexual cues compared to control cues. Study 4 demonstrated that the positive affect resulting from exposure to subliminal sexual cues increased motivation to further engage in a neutral task. Study 5 provided evidence suggesting that the affect and motivation found in Studies 1–4 were associated with motivation to engage in sex specifically, rather than a general approach motivation. The implications of these findings for the processing of subliminal sexual cues and for human sexuality are discussed. PMID:26494359

  10. Numerical modeling on air quality in an urban environment with changes of the aspect ratio and wind direction.

    PubMed

    Yassin, Mohamed F

    2013-06-01

    Due to heavy traffic emissions within an urban environment, air quality during the last decade becomes worse year by year and hazard to public health. In the present work, numerical modeling of flow and dispersion of gaseous emissions from vehicle exhaust in a street canyon were investigated under changes of the aspect ratio and wind direction. The three-dimensional flow and dispersion of gaseous pollutants were modeled using a computational fluid dynamics (CFD) model which was numerically solved using Reynolds-averaged Navier-Stokes (RANS) equations. The diffusion flow field in the atmospheric boundary layer within the street canyon was studied for different aspect ratios (W/H=1/2, 3/4, and 1) and wind directions (θ=90°, 112.5°, 135°, and 157.5°). The numerical models were validated against wind tunnel results to optimize the turbulence model. The numerical results agreed well with the wind tunnel results. The simulation demonstrated that the minimum concentration at the human respiration height within the street canyon was on the windward side for aspect ratios W/H=1/2 and 1 and wind directions θ=112.5°, 135°, and 157.5°. The pollutant concentration level decreases as the wind direction and aspect ratio increase. The wind velocity and turbulence intensity increase as the aspect ratio and wind direction increase.

  11. Software Aspects of IEEE Floating-Point Computations for Numerical Applications in High Energy Physics

    ScienceCinema

    None

    2016-07-12

    Floating-point computations are at the heart of much of the computing done in high energy physics. The correctness, speed and accuracy of these computations are of paramount importance. The lack of any of these characteristics can mean the difference between new, exciting physics and an embarrassing correction. This talk will examine practical aspects of IEEE 754-2008 floating-point arithmetic as encountered in HEP applications. After describing the basic features of IEEE floating-point arithmetic, the presentation will cover: common hardware implementations (SSE, x87) techniques for improving the accuracy of summation, multiplication and data interchange compiler options for gcc and icc affecting floating-point operations hazards to be avoided About the speaker Jeffrey M Arnold is a Senior Software Engineer in the Intel Compiler and Languages group at Intel Corporation. He has been part of the Digital->Compaq->Intel compiler organization for nearly 20 years; part of that time, he worked on both low- and high-level math libraries. Prior to that, he was in the VMS Engineering organization at Digital Equipment Corporation. In the late 1980s, Jeff spent 2½ years at CERN as part of the CERN/Digital Joint Project. In 2008, he returned to CERN to spent 10 weeks working with CERN/openlab. Since that time, he has returned to CERN multiple times to teach at openlab workshops and consult with various LHC experiments. Jeff received his Ph.D. in physics from Case Western Reserve University.

  12. Software Aspects of IEEE Floating-Point Computations for Numerical Applications in High Energy Physics

    SciTech Connect

    2010-05-11

    Floating-point computations are at the heart of much of the computing done in high energy physics. The correctness, speed and accuracy of these computations are of paramount importance. The lack of any of these characteristics can mean the difference between new, exciting physics and an embarrassing correction. This talk will examine practical aspects of IEEE 754-2008 floating-point arithmetic as encountered in HEP applications. After describing the basic features of IEEE floating-point arithmetic, the presentation will cover: common hardware implementations (SSE, x87) techniques for improving the accuracy of summation, multiplication and data interchange compiler options for gcc and icc affecting floating-point operations hazards to be avoided About the speaker Jeffrey M Arnold is a Senior Software Engineer in the Intel Compiler and Languages group at Intel Corporation. He has been part of the Digital->Compaq->Intel compiler organization for nearly 20 years; part of that time, he worked on both low- and high-level math libraries. Prior to that, he was in the VMS Engineering organization at Digital Equipment Corporation. In the late 1980s, Jeff spent 2½ years at CERN as part of the CERN/Digital Joint Project. In 2008, he returned to CERN to spent 10 weeks working with CERN/openlab. Since that time, he has returned to CERN multiple times to teach at openlab workshops and consult with various LHC experiments. Jeff received his Ph.D. in physics from Case Western Reserve University.

  13. Understanding the emotional aspects of escalation of commitment: the role of negative affect.

    PubMed

    Wong, Kin Fai Ellick; Yik, Michelle; Kwong, Jessica Y Y

    2006-03-01

    Despite the importance of understanding the emotional aspects of organizational decision making, prior research has paid scant attention to the role of emotion in escalation of commitment. This article attempts to fill this gap by examining the relationship between negative affect and escalation of commitment. Results showed that regardless of whether negative affect was measured as a dispositional trait (Neuroticism) in Studies 1 and 2 or as a transient mood state in Study 3, it was negatively correlated with escalation tendency when one was personally responsible for a prior decision. This pattern of results is consistent with the predictions derived from the coping perspective, suggesting that people seek to escape from the unpleasant emotions that are associated with escalation situations.

  14. Chronic Loss of Melanin-Concentrating Hormone Affects Motivational Aspects of Feeding in the Rat

    PubMed Central

    Mul, Joram D.; la Fleur, Susanne E.; Toonen, Pim W.; Afrasiab-Middelman, Anthonieke; Binnekade, Rob; Schetters, Dustin; Verheij, Michel M. M.; Sears, Robert M.; Homberg, Judith R.; Schoffelmeer, Anton N. M.; Adan, Roger A. H.; DiLeone, Ralph J.; De Vries, Taco J.; Cuppen, Edwin

    2011-01-01

    Current epidemic obesity levels apply great medical and financial pressure to the strenuous economy of obesity-prone cultures, and neuropeptides involved in body weight regulation are regarded as attractive targets for a possible treatment of obesity in humans. The lateral hypothalamus and the nucleus accumbens shell (AcbSh) form a hypothalamic-limbic neuropeptide feeding circuit mediated by Melanin-Concentrating Hormone (MCH). MCH promotes feeding behavior via MCH receptor-1 (MCH1R) in the AcbSh, although this relationship has not been fully characterized. Given the AcbSh mediates reinforcing properties of food, we hypothesized that MCH modulates motivational aspects of feeding. Here we show that chronic loss of the rat MCH-precursor Pmch decreased food intake predominantly via a reduction in meal size during rat development and reduced high-fat food-reinforced operant responding in adult rats. Moreover, acute AcbSh administration of Neuropeptide-GE and Neuropeptide-EI (NEI), both additional neuropeptides derived from Pmch, or chronic intracerebroventricular infusion of NEI, did not affect feeding behavior in adult pmch+/+ or pmch−/− rats. However, acute administration of MCH to the AcbSh of adult pmch−/− rats elevated feeding behavior towards wild type levels. Finally, adult pmch−/− rats showed increased ex vivo electrically evoked dopamine release and increased limbic dopamine transporter levels, indicating that chronic loss of Pmch in the rat affects the limbic dopamine system. Our findings support the MCH-MCH1R system as an amplifier of consummatory behavior, confirming this system as a possible target for the treatment of obesity. We propose that MCH-mediated signaling in the AcbSh positively mediates motivational aspects of feeding behavior. Thereby it provides a crucial signal by which hypothalamic neural circuits control energy balance and guide limbic brain areas to enhance motivational or incentive-related aspects of food consumption. PMID

  15. Numerical Study of the Effect of the Sample Aspect Ratio on the Ductility of Bulk Metallic Glasses (BMGs) Under Compression

    NASA Astrophysics Data System (ADS)

    Jiang, Yunpeng

    2016-05-01

    In this article, a systematic numerical study was conducted to study the detailed shear banding evolution in bulk metallic glasses (BMGs) with various sample aspect ratios under uniaxial compression, and whereby the effect of the sample aspect ratio on the compressive ductility was elucidated. A finite strain viscoelastic model was employed to describe the shear banding nucleation, growth, and coalescence in BMG samples with the help of Anand and Su's theory, which was incorporated into the ABAQUS finite element method code as a user material subroutine VUMAT. The present numerical method was first verified by comparing with the corresponding experimental results, and then parameter analysis was performed to discuss the impact of microstructure parameters on the predicted results. The present modeling will shed some light on enhancing the toughness of BMG structures in the engineering applications.

  16. Epidemiological aspects of rheumatoid arthritis patients affected by oral bisphosphonate-related osteonecrosis of the jaws

    PubMed Central

    2012-01-01

    This literature review aims to evaluate the epidemiologic profile of patients with rheumatoid arthritis (RA) that developed a bisphosphonate-related osteonecrosis that affect the jaws (BRONJ), including demographic aspects, as well as clinical and therapeutic issues. A search of PUBMED/MEDLINE, Scopus, and Cochrane databases from January 2003 to September 2011 was conducted with the objective of identifying publications that contained case reports regarding oral BRONJ in RA patients. Patients with RA who develop oral BRONJ are usually women above 60 years taking steroids and long-term alendronate. Most of them have osteoporosis, and lesions, triggered by dental procedures, are usually detected at stage II in the mandible. Although there is no accepted treatment protocol, these patients seem to have better outcomes with conservative approaches that include antibiotic therapy, chlorhexidine, and drug discontinuation. PMID:22376948

  17. Simulation and investigation of factors affecting high aspect ratio UV embossing.

    PubMed

    Chan-Park, Mary B; Lam, Y C; Laulia, P; Joshi, S C

    2005-03-01

    UV embossing is a replication method whereby an UV-curable polymer is pressed against a patterned mold and cured with UV irradiation, resulting in a patterned polymeric substrate. High aspect ratio UV embossing will find diverse applications in tissue engineering, micro-optics, display technologies, and sensors. Demolding of an UV-embossed polymer pattern with aspect ratio of 5 from the mold has previously been demonstrated experimentally. In this paper, parameters that affect the demolding process have been identified and investigated. They include cross-linking shrinkage during curing by UV irradiation, modulus of cured polymer, interfacial fracture strength and toughness, and loading method during demolding. Shrinkage is an important parameter, and an optimum level of shrinkage to avoid breakage of the embossing during demolding was found to exist. This optimum level is that at which the maximum stress (sigma(1)max) experienced by the polymer during demolding is minimized. The micromechanics of demolding was found to be different for shrinkage values lower or larger than the optimum value. PMID:15723501

  18. Nonlinear evolution of cylindrical gravitational waves: Numerical method and physical aspects

    NASA Astrophysics Data System (ADS)

    Celestino, Juliana; de Oliveira, H. P.; Rodrigues, E. L.

    2016-05-01

    General cylindrical waves are the simplest axisymmetrical gravitational waves that contain both + and × modes of polarization. In this paper, we have studied the evolution of general cylindrical gravitational waves in the realm of the characteristic scheme with a numerical code based on the Galerkin-Collocation method. The investigation consists of the numerical realization of concepts such as Bondi mass and the news functions adapted to cylindrical symmetry. The Bondi mass decays due to the presence of the news functions associated with both polarization modes. We have interpreted each polarization mode as channels from which mass is extracted. Under this perspective, we have presented the enhancement effect of the polarization mode + due to the nonlinear interaction with the mode ×. After discussing the role of matter in cylindrical symmetry, we have extended the numerical code to include electromagnetic fields.

  19. The Role of a Steepness Parameter in the Exponential Stability of a Model Problem. Numerical Aspects

    NASA Astrophysics Data System (ADS)

    Todorovic, N.

    2011-06-01

    The Nekhoroshev theorem considers quasi integrable Hamiltonians providing stability of actions in exponentially long times. One of the hypothesis required by the theorem is a mathematical condition called steepness. Nekhoroshev conjectured that different steepness properties should imply numerically observable differences in the stability times. After a recent study on this problem (Guzzo et al. 2011, Todorovic et al. 2011) we show some additional numerical results on the change of resonances and the diffusion laws produced by the increasing effect of steepness. The experiments are performed on a 4-dimensional steep symplectic map designed in a way that a parameter smoothly regulates the steepness properties in the model.

  20. STN1 OB Fold Mutation Alters DNA Binding and Affects Selective Aspects of CST Function

    PubMed Central

    Bhattacharjee, Anukana; Stewart, Jason; Chaiken, Mary; Price, Carolyn M.

    2016-01-01

    Mammalian CST (CTC1-STN1-TEN1) participates in multiple aspects of telomere replication and genome-wide recovery from replication stress. CST resembles Replication Protein A (RPA) in that it binds ssDNA and STN1 and TEN1 are structurally similar to RPA2 and RPA3. Conservation between CTC1 and RPA1 is less apparent. Currently the mechanism underlying CST action is largely unknown. Here we address CST mechanism by using a DNA-binding mutant, (STN1 OB-fold mutant, STN1-OBM) to examine the relationship between DNA binding and CST function. In vivo, STN1-OBM affects resolution of endogenous replication stress and telomere duplex replication but telomeric C-strand fill-in and new origin firing after exogenous replication stress are unaffected. These selective effects indicate mechanistic differences in CST action during resolution of different replication problems. In vitro binding studies show that STN1 directly engages both short and long ssDNA oligonucleotides, however STN1-OBM preferentially destabilizes binding to short substrates. The finding that STN1-OBM affects binding to only certain substrates starts to explain the in vivo separation of function observed in STN1-OBM expressing cells. CST is expected to engage DNA substrates of varied length and structure as it acts to resolve different replication problems. Since STN1-OBM will alter CST binding to only some of these substrates, the mutant should affect resolution of only a subset of replication problems, as was observed in the STN1-OBM cells. The in vitro studies also provide insight into CST binding mechanism. Like RPA, CST likely contacts DNA via multiple OB folds. However, the importance of STN1 for binding short substrates indicates differences in the architecture of CST and RPA DNA-protein complexes. Based on our results, we propose a dynamic DNA binding model that provides a general mechanism for CST action at diverse forms of replication stress. PMID:27690379

  1. Cognitive and Affective Aspects of Creative Option Generation in Everyday Life Situations

    PubMed Central

    Schweizer, T. Sophie; Schmalenberger, Katja M.; Eisenlohr-Moul, Tory A.; Mojzisch, Andreas; Kaiser, Stefan; Funke, Joachim

    2016-01-01

    Which factors influence a human being’s ability to develop new perspectives and be creative? This ability is pivotal for any context in which new cognitions are required, such as innovative endeavors in science and art, or psychotherapeutic settings. In this article, we seek to bring together two research programs investigating the generation of creative options: On the one hand, research on option generation in the decision-making literature and, on the other hand, cognitive and clinical creativity research. Previous decision-making research has largely neglected the topic of generating creative options. Experiments typically provided participants with a clear set of options to choose from, but everyday life situations are less structured and allow countless ways to react. Before choosing an option, agents have to self-generate a set of options to choose from. Such option generation processes have only recently moved to the center of attention. The present study examines the creative quality of self-generated options in daily life situations. A student sample (N = 48) generated options for action in 70 briefly described everyday life scenarios. We rated the quality of the options on three dimensions of creativity- originality, feasibility, and divergence -and linked these qualities to option generation fluency (speed and number of generated options), situational features like the familiarity and the affective valence of the situation in which the options were generated, and trait measures of cognitive performance. We found that when situations were familiar to the participant, greater negative affective valence of the situation was associated with more originality and divergence of generated options. We also found that a higher option generation fluency was associated with a greater maximal originality of options. We complete our article with a joint research agenda for researchers in the decision-making field focusing on option generation and, on the other hand

  2. Single locus affects embryonic segment polarity and multiple aspects of an adult evolutionary novelty

    PubMed Central

    2010-01-01

    Background The characterization of the molecular changes that underlie the origin and diversification of morphological novelties is a key challenge in evolutionary developmental biology. The evolution of such traits is thought to rely largely on co-option of a toolkit of conserved developmental genes that typically perform multiple functions. Mutations that affect both a universal developmental process and the formation of a novelty might shed light onto the genetics of traits not represented in model systems. Here we describe three pleiotropic mutations with large effects on a novel trait, butterfly eyespots, and on a conserved stage of embryogenesis, segment polarity. Results We show that three mutations affecting eyespot size and/or colour composition in Bicyclus anynana butterflies occurred in the same locus, and that two of them are embryonic recessive lethal. Using surgical manipulations and analysis of gene expression patterns in developing wings, we demonstrate that the effects on eyespot morphology are due to changes in the epidermal response component of eyespot induction. Our analysis of morphology and of gene expression in mutant embryos shows that they have a typical segment polarity phenotype, consistent with the mutant locus encoding a negative regulator of Wingless signalling. Conclusions This study characterizes the segregation and developmental effects of alleles at a single locus that controls the morphology of a lineage-specific trait (butterfly eyespots) and a conserved process (embryonic segment polarity and, specifically, the regulation of Wingless signalling). Because no gene with such function was found in the orthologous, highly syntenic genomic regions of two other lepidopterans, we hypothesize that our locus is a yet undescribed, possibly lineage-specific, negative regulator of the conserved Wnt/Wg pathway. Moreover, the fact that this locus interferes with multiple aspects of eyespot morphology and maps to a genomic region containing

  3. Cognitive and Affective Aspects of Creative Option Generation in Everyday Life Situations.

    PubMed

    Schweizer, T Sophie; Schmalenberger, Katja M; Eisenlohr-Moul, Tory A; Mojzisch, Andreas; Kaiser, Stefan; Funke, Joachim

    2016-01-01

    Which factors influence a human being's ability to develop new perspectives and be creative? This ability is pivotal for any context in which new cognitions are required, such as innovative endeavors in science and art, or psychotherapeutic settings. In this article, we seek to bring together two research programs investigating the generation of creative options: On the one hand, research on option generation in the decision-making literature and, on the other hand, cognitive and clinical creativity research. Previous decision-making research has largely neglected the topic of generating creative options. Experiments typically provided participants with a clear set of options to choose from, but everyday life situations are less structured and allow countless ways to react. Before choosing an option, agents have to self-generate a set of options to choose from. Such option generation processes have only recently moved to the center of attention. The present study examines the creative quality of self-generated options in daily life situations. A student sample (N = 48) generated options for action in 70 briefly described everyday life scenarios. We rated the quality of the options on three dimensions of creativity- originality, feasibility, and divergence -and linked these qualities to option generation fluency (speed and number of generated options), situational features like the familiarity and the affective valence of the situation in which the options were generated, and trait measures of cognitive performance. We found that when situations were familiar to the participant, greater negative affective valence of the situation was associated with more originality and divergence of generated options. We also found that a higher option generation fluency was associated with a greater maximal originality of options. We complete our article with a joint research agenda for researchers in the decision-making field focusing on option generation and, on the other hand

  4. RESONANT ABSORPTION OF TRANSVERSE OSCILLATIONS AND ASSOCIATED HEATING IN A SOLAR PROMINENCE. II. NUMERICAL ASPECTS

    SciTech Connect

    Antolin, P.; Okamoto, T. J.; Doorsselaere, T. Van; Yokoyama, T.

    2015-08-10

    Transverse magnetohydrodynamic (MHD) waves are ubiquitous in the solar atmosphere and may be responsible for generating the Sun’s million-degree outer atmosphere. However, direct evidence of the dissipation process and heating from these waves remains elusive. Through advanced numerical simulations combined with appropriate forward modeling of a prominence flux tube, we provide the observational signatures of transverse MHD waves in prominence plasmas. We show that these signatures are characterized by a thread-like substructure, strong transverse dynamical coherence, an out-of-phase difference between plane-of-the-sky motions and line-of-sight velocities, and enhanced line broadening and heating around most of the flux tube. A complex combination between resonant absorption and Kelvin–Helmholtz instabilities (KHIs) takes place in which the KHI extracts the energy from the resonant layer and dissipates it through vortices and current sheets, which rapidly degenerate into turbulence. An inward enlargement of the boundary is produced in which the turbulent flows conserve the characteristic dynamics from the resonance, therefore guaranteeing detectability of the resonance imprints. We show that the features described in the accompanying paper through coordinated Hinode and Interface Region Imaging Spectrograph observations match the numerical results well.

  5. Natural selection affects multiple aspects of genetic variation at putatively neutral sites across the human genome.

    PubMed

    Lohmueller, Kirk E; Albrechtsen, Anders; Li, Yingrui; Kim, Su Yeon; Korneliussen, Thorfinn; Vinckenbosch, Nicolas; Tian, Geng; Huerta-Sanchez, Emilia; Feder, Alison F; Grarup, Niels; Jørgensen, Torben; Jiang, Tao; Witte, Daniel R; Sandbæk, Annelli; Hellmann, Ines; Lauritzen, Torsten; Hansen, Torben; Pedersen, Oluf; Wang, Jun; Nielsen, Rasmus

    2011-10-01

    A major question in evolutionary biology is how natural selection has shaped patterns of genetic variation across the human genome. Previous work has documented a reduction in genetic diversity in regions of the genome with low recombination rates. However, it is unclear whether other summaries of genetic variation, like allele frequencies, are also correlated with recombination rate and whether these correlations can be explained solely by negative selection against deleterious mutations or whether positive selection acting on favorable alleles is also required. Here we attempt to address these questions by analyzing three different genome-wide resequencing datasets from European individuals. We document several significant correlations between different genomic features. In particular, we find that average minor allele frequency and diversity are reduced in regions of low recombination and that human diversity, human-chimp divergence, and average minor allele frequency are reduced near genes. Population genetic simulations show that either positive natural selection acting on favorable mutations or negative natural selection acting against deleterious mutations can explain these correlations. However, models with strong positive selection on nonsynonymous mutations and little negative selection predict a stronger negative correlation between neutral diversity and nonsynonymous divergence than observed in the actual data, supporting the importance of negative, rather than positive, selection throughout the genome. Further, we show that the widespread presence of weakly deleterious alleles, rather than a small number of strongly positively selected mutations, is responsible for the correlation between neutral genetic diversity and recombination rate. This work suggests that natural selection has affected multiple aspects of linked neutral variation throughout the human genome and that positive selection is not required to explain these observations.

  6. Percolation in sign-symmetric random fields: topological aspects and numerical modeling

    PubMed

    Milovanov; Zimbardo

    2000-07-01

    The topology of percolation in random scalar fields psi(x) with sign symmetry [i.e., that the statistical properties of the functions psi(x) and -psi(x) are identical] is analyzed. Based on methods of general topology, we show that the zero set psi(x)=0 of the n-dimensional (n>/=2) sign-symmetric random field psi(x) contains a (connected) percolating subset under the condition |nablapsi(x)| not equal0 everywhere except in domains of negligible measure. The fractal geometry of percolation is analyzed in more detail in the particular case of the two-dimensional (n=2) fields psi(x). The improved Alexander-Orbach conjecture [Phys. Rev. E 56, 2437 (1997)] is applied analytically to obtain estimates of the main fractal characteristics of the percolating fractal sets generated by the horizontal "cuts," psi(x)=h, of the field psi(x). These characteristics are the Hausdorff fractal dimension of the set, D, and the index of connectivity, straight theta. We advocate an unconventional approach to studying the geometric properties of fractals, which involves methods of homotopic topology. It is shown that the index of connectivity, straight theta, of a fractal set is the topological invariant of this set, i.e., it remains unchanged under the homeomorphic deformations of the fractal. This issue is explicitly used in our study to find the Hausdorff fractal dimension of the single isolevels of the field psi(x), as well as the related geometric quantities. The results obtained are analyzed numerically in the particular case when the random field psi(x) is given by a fractional Brownian surface whose topological properties recover well the main assumptions of our consideration.

  7. Neural substrates for the processing of cognitive and affective aspects of taste in the brain.

    PubMed

    Yamamoto, Takashi

    2006-12-01

    Taste is unique among the sensory systems in that, besides its recognition of quality, it is innately associated with hedonic aspects of reward and aversion. This review of the literature will show how taste information is conveyed through the central gustatory pathways to the cortical gustatory area and is processed in terms of qualitative and quantitative aspects. Taste information is also sent to the reward system and feeding center via several brain sites including the prefrontal cortex, insular cortex, and amygdala. The reward system contains the ventral tegmental area, nucleus accumbens, and ventral pallidum; it finally sends information to the lateral hypothalamic area, the feeding center. The dopamine system originating from the ventral tegmental area mediates the motivation to consume palatable food. The actual ingestive behavior is promoted by the orexigenic neuropeptides from the hypothalamus. In the last section, the neural substrate of learning and memory of taste is introduced and the biological mechanisms are elucidated. PMID:17287579

  8. Structural Aspects of Railway Truss Bridges Affecting Transverse Shear Forces in Steel-Concrete Composite Decks

    NASA Astrophysics Data System (ADS)

    Siekierski, Wojciech

    2015-03-01

    At the steel-concrete interface, the horizontal shear forces that are transverse to cross beams occur due to joint action of the steel-concrete composite deck and the truss girders. Numerical analysis showed that values of the forces are big in comparison to the longitudinal shear forces. In both cases extreme force values occur near side edges of a slab. The paper studies possibilities of reduction of these shear forces by structural alterations of the following: rigidity of a concrete slab, arrangement of a wind bracing, arrangement of concrete slab expansion joints. An existing railway truss bridge span has been analysed. Numerical analysis shows that it is possible to reduce the values of shear forces transverse to cross beams. It may reach 20% near the side edges of slabs and 23% in the centre of slab width.

  9. Factors affecting air sparging remediation systems using field data and numerical simulations.

    PubMed

    Benner, Michael L; Mohtar, Rabi H; Lee, Linda S

    2002-12-01

    Field data from five air sparging sites were used to assess the effect of several soil, contaminant, and air sparging system factors on the removal time and associated costs required to reach specified clean-up criteria. Numerical simulations were also performed to better assess the field data and to expand the data sets beyond the five field sites. Ten factors were selected and evaluated individually over a range of values based on information from practitioners and the literature. Trends in removal time and removal cost to reach a specified clean-up criterion were analyzed to ascertain the conditions controlling contaminant removal with variations in each factors' value. A linear sensitivity equation was used to quantify system dynamics controlling the observed contaminant removal trends for each factor. Factors found most critical across all field sites in terms of removal time and/or cost were contaminant type, sparge pulsing schedule, number of wells, maximum biodecay rate, total soil porosity, and aquifer organic carbon content. Factors showing moderate to low effect included the depth of the sparge point below the water table, air injection rate/pressure, horizontal air conductivity, and anisotropy ratio. At each field site, subsurface coverage of sparged air, sparged air residence time, contaminant equilibrium in the system, contaminant phase distribution, oxygen availability to microbes, and contaminant volatility seem to control the system responses and were affected by one or more of the 10 factors evaluated.

  10. Psychological aspects in children affected by duchenne de boulogne muscular dystrophy.

    PubMed

    Filippo, Teresa Di; Parisi, Lucia; Roccella, Michele

    2012-07-26

    Impairment of intelligence in Duchenne muscular dystrophy (DMD) patients was described by Duchenne de Boulogne himself in 1868. Further studies report intelligence disorders with mayor impairment of memory. The aim of the present study was to assess the presence of affective and personality disorders in a group of children affected by DMD. Twenty six male DMD patients, mean age eleven and four months years old, were assessed for their affective and personality disorder. Only eight subjects had a total IQ below average with major difficulties in verbal and visual-spatial memory, comprehension, arithmetic and vocabulary. All the subjects presented some disorders: tendency to marginalization and isolation, self-depreciation, sense of insecurity, hypochondriac thoughts and marked state of anxiety. These disorders are often a dynamic prolongation of a psychological process which starts when the diagnosis is made and continues, in a slow and latent fashion, throughout the evolution of the disease. PMID:25478112

  11. Psychological Aspects in Children Affected by Duchenne De Boulogne Muscular Dystrophy

    PubMed Central

    Parisi, Lucia; Roccella, Michele

    2014-01-01

    Impairment of intelligence in Duchenne muscular dystrophy (DMD) patients was described by Duchenne de Boulogne himself in 1868. Further studies report intelligence disorders with mayor impairment of memory. The aim of the present study was to assess the presence of affective and personality disorders in a group of children affected by DMD. Twenty six male DMD patients, mean age eleven and four months years old, were assessed for their affective and personality disorder. Only eight subjects had a total IQ below average with major difficulties in verbal and visual-spatial memory, comprehension, arithmetic and vocabulary. All the subjects presented some disorders: tendency to marginalization and isolation, self-depreciation, sense of insecurity, hypochondriac thoughts and marked state of anxiety. These disorders are often a dynamic prolongation of a psychological process which starts when the diagnosis is made and continues, in a slow and latent fashion, throughout the evolution of the disease. PMID:25478112

  12. ALE meta‐analysis reveals dissociable networks for affective and discriminative aspects of touch

    PubMed Central

    2016-01-01

    Abstract Emotionally‐laden tactile stimulation—such as a caress on the skin or the feel of velvet—may represent a functionally distinct domain of touch, underpinned by specific cortical pathways. In order to determine whether, and to what extent, cortical functional neuroanatomy supports a distinction between affective and discriminative touch, an activation likelihood estimate (ALE) meta‐analysis was performed. This meta‐analysis statistically mapped reported functional magnetic resonance imaging (fMRI) activations from 17 published affective touch studies in which tactile stimulation was associated with positive subjective evaluation (n = 291, 34 experimental contrasts). A separate ALE meta‐analysis mapped regions most likely to be activated by tactile stimulation during detection and discrimination tasks (n = 1,075, 91 experimental contrasts). These meta‐analyses revealed dissociable regions for affective and discriminative touch, with posterior insula (PI) more likely to be activated for affective touch, and primary somatosensory cortices (SI) more likely to be activated for discriminative touch. Secondary somatosensory cortex had a high likelihood of engagement by both affective and discriminative touch. Further, meta‐analytic connectivity (MCAM) analyses investigated network‐level co‐activation likelihoods independent of task or stimulus, across a range of domains and paradigms. Affective‐related PI and discriminative‐related SI regions co‐activated with different networks, implicated in dissociable functions, but sharing somatosensory co‐activations. Taken together, these meta‐analytic findings suggest that affective and discriminative touch are dissociable both on the regional and network levels. However, their degree of shared activation likelihood in somatosensory cortices indicates that this dissociation reflects functional biases within tactile processing networks, rather than functionally and anatomically distinct

  13. Slope aspect affects geomorphic dynamics of coal mining spoil heaps in Belgium

    NASA Astrophysics Data System (ADS)

    Nyssen, Jan; Vermeersch, Dominiek

    2010-11-01

    After the abandonment of coal mining in Belgium in the 1960s-1980s, many coal tips have been left to themselves. Increasingly, these coal tips are regarded as socio-cultural heritage and protected for their environmental value. This research analyses the spatial distribution of the main geomorphic processes (sheet and rill erosion, landsliding, rock fragment movement and root throw) occurring on coal tips in Belgium, through mapping of the processes and their causal factors. Five spoil heaps spread over the major coal basins were studied in detail. The spoil heaps were subdivided in homogeneous land units, especially with regard to slope gradient, vegetation cover and slope aspect. Qualitative and quantitative observations were done on processes and potential causal factors. Regressions showed that generally, the expression of slope processes on the studied coal tips is (1) strongly dependent on westerly aspect of the slopes, (2) independent of slope gradient (which presents a narrow range), (3) impeded by grass cover, and (4) not fully predictable due to variability in type and age of dumped mine spoil.

  14. Affective Aspects on Mathematics Conceptualization: From Dichotomies to an Integrated Approach

    ERIC Educational Resources Information Center

    Araujo, Claudia Roberta; Andrade, Fernanda; Hazin, Izabel; Falcao, Jorge Tarcisio da Rocha; do Nascimento, Jorge Costa; Lessa, Monica Maria Lins

    2003-01-01

    The present paper aims to propose a theoretical reflection in order to overcome a strong tradition in psychology concerning the analysis of cognition and affectivity as dichotomic processes explaining human behaviours. A general theory of the human subject is presented to discussion, followed by the proposition of a new unit of analysis for the…

  15. Aspects on antidote therapy in acute poisoning affecting the nervous system.

    PubMed

    Persson, H

    1984-01-01

    The number of toxic substances affecting the nervous system through acute or chronic exposure is overwhelming. This survey will elucidate the possibilities of antidote therapy in some acute cases of poisoning, caused by nervous system toxicants. Antidotes exert their therapeutic effects through a variety of mechanisms: Adsorption, formation of inert complexes, inhibited conversion to toxic metabolites, enhancement of endogenous detoxification, interference at receptor sites, and physiological antagonism. The application of these principles in treating some poisonings caused by important nervous system toxicants will be considered. This survey is by no means comprehensive, but rather gives some relevant examples and deals only with acute poisoning.

  16. Do increases in selected fitness parameters affect the aesthetic aspects of classical ballet performance?

    PubMed

    Twitchett, Emily A; Angioi, Manuela; Koutedakis, Yiannis; Wyon, Matthew

    2011-03-01

    Research has indicated that classical ballet dancers tend to have lower fitness levels and increased injury rates compared to other athletes with similar workloads. The aim of the current study was to examine the effects of a specifically tailored fitness training programme on the incidence of injury and the aesthetic quality of performance of classical ballet dancers compared to a control group. Proficiency in performance was evaluated at the beginning and end of the intervention period for both groups through a 4-min dance sequence using previously ratified marking criteria. The intervention group (n = 8) partook in a weekly 1-hr training session that included aerobic interval training, circuit training, and whole body vibration. All dancers' performance proficiency scores increased from pre-intervention testing to post-intervention. The intervention group's overall performance scores demonstrated a significantly greater increase (p = 0.03) than the equivalent for the control group. It was concluded that supplementary fitness training has a positive effect on aspects related to aesthetic dance performance as studied herein; further research is recommended on a larger and more varied sample. Practical applications from this study suggest that supplemental training should be part of a ballet dancer's regime, and minimal intervention time is required to have observable effects.

  17. Aspects of social cognition in anorexia nervosa: affective and cognitive theory of mind.

    PubMed

    Russell, Tamara Anne; Schmidt, Ulrike; Doherty, Liz; Young, Vicky; Tchanturia, Kate

    2009-08-15

    Although social functioning is clearly impaired in anorexia nervosa (AN), there has been limited empirical assessment of this domain in this illness. This study assesses social cognition in AN by examining performance on two 'theory of mind' (ToM) tasks; Baron-Cohen's "Reading the mind in the Eyes" task (RME) and Happé's cartoon task. These tasks probe affective and cognitive ToM, respectively. Forty-four female participants were recruited (AN N=22; healthy controls N=22) and completed both tasks, with concurrent clinical and intellectual functioning assessment. Compared with healthy controls, AN performed significantly worse on both the RME and the Cartoon task (both conditions). The mental state condition did not facilitate performance in the AN group, as it did in the healthy controls. The findings broadly replicate limited previous work [Tchanturia, K., Happé, F., Godley, J., Bara-Carill, N., Treasure, J., Schmidt, U., 2004. Theory of mind in AN. European Eating Disorders Review 12, 361-366] but in addition demonstrate abnormalities on a task requiring affective ToM interpretation. More detailed information about the components of ToM and the ToM difficulties demonstrated in AN sufferers may inform our understanding of the disorder as well as future social-cognitive based treatments.

  18. Numerical investigation of non-Newtonian fluids in annular ducts with finite aspect ratio using lattice Boltzmann method

    NASA Astrophysics Data System (ADS)

    Khali, S.; Nebbali, R.; Ameziani, D. E.; Bouhadef, K.

    2013-05-01

    In this work the instability of the Taylor-Couette flow for Newtonian and non-Newtonian fluids (dilatant and pseudoplastic fluids) is investigated for cases of finite aspect ratios. The study is conducted numerically using the lattice Boltzmann method (LBM). In many industrial applications, the apparatuses and installations drift away from the idealized case of an annulus of infinite length, and thus the end caps effect can no longer be ignored. The inner cylinder is rotating while the outer one and the end walls are maintained at rest. The lattice two-dimensional nine-velocity (D2Q9) Boltzmann model developed from the Bhatnagar-Gross-Krook approximation is used to obtain the flow field for fluids obeying the power-law model. The combined effects of the Reynolds number, the radius ratio, and the power-law index n on the flow characteristics are analyzed for an annular space of finite aspect ratio. Two flow modes are obtained: a primary Couette flow (CF) mode and a secondary Taylor vortex flow (TVF) mode. The flow structures so obtained are different from one mode to another. The critical Reynolds number Rec for the passage from the primary to the secondary mode exhibits the lowest value for the pseudoplastic fluids and the highest value for the dilatant fluids. The findings are useful for studies of the swirling flow of non-Newtonians fluids in axisymmetric geometries using LBM. The flow changes from the CF to TVF and its structure switches from the two-cells to four-cells regime for both Newtonian and dilatant fluids. Contrariwise for pseudoplastic fluids, the flow exhibits 2-4-2 structure passing from two-cells to four cells and switches again to the two-cells configuration. Furthermore, the critical Reynolds number presents a monotonic increase with the power-law index n of the non-Newtonian fluid, and as the radius ratio grows, the transition flow regimes tend to appear for higher critical Reynolds numbers.

  19. Numerical investigation of non-Newtonian fluids in annular ducts with finite aspect ratio using lattice Boltzmann method.

    PubMed

    Khali, S; Nebbali, R; Ameziani, D E; Bouhadef, K

    2013-05-01

    In this work the instability of the Taylor-Couette flow for Newtonian and non-Newtonian fluids (dilatant and pseudoplastic fluids) is investigated for cases of finite aspect ratios. The study is conducted numerically using the lattice Boltzmann method (LBM). In many industrial applications, the apparatuses and installations drift away from the idealized case of an annulus of infinite length, and thus the end caps effect can no longer be ignored. The inner cylinder is rotating while the outer one and the end walls are maintained at rest. The lattice two-dimensional nine-velocity (D2Q9) Boltzmann model developed from the Bhatnagar-Gross-Krook approximation is used to obtain the flow field for fluids obeying the power-law model. The combined effects of the Reynolds number, the radius ratio, and the power-law index n on the flow characteristics are analyzed for an annular space of finite aspect ratio. Two flow modes are obtained: a primary Couette flow (CF) mode and a secondary Taylor vortex flow (TVF) mode. The flow structures so obtained are different from one mode to another. The critical Reynolds number Re(c) for the passage from the primary to the secondary mode exhibits the lowest value for the pseudoplastic fluids and the highest value for the dilatant fluids. The findings are useful for studies of the swirling flow of non-Newtonians fluids in axisymmetric geometries using LBM. The flow changes from the CF to TVF and its structure switches from the two-cells to four-cells regime for both Newtonian and dilatant fluids. Contrariwise for pseudoplastic fluids, the flow exhibits 2-4-2 structure passing from two-cells to four cells and switches again to the two-cells configuration. Furthermore, the critical Reynolds number presents a monotonic increase with the power-law index n of the non-Newtonian fluid, and as the radius ratio grows, the transition flow regimes tend to appear for higher critical Reynolds numbers.

  20. Numerical investigation of non-Newtonian fluids in annular ducts with finite aspect ratio using lattice Boltzmann method.

    PubMed

    Khali, S; Nebbali, R; Ameziani, D E; Bouhadef, K

    2013-05-01

    In this work the instability of the Taylor-Couette flow for Newtonian and non-Newtonian fluids (dilatant and pseudoplastic fluids) is investigated for cases of finite aspect ratios. The study is conducted numerically using the lattice Boltzmann method (LBM). In many industrial applications, the apparatuses and installations drift away from the idealized case of an annulus of infinite length, and thus the end caps effect can no longer be ignored. The inner cylinder is rotating while the outer one and the end walls are maintained at rest. The lattice two-dimensional nine-velocity (D2Q9) Boltzmann model developed from the Bhatnagar-Gross-Krook approximation is used to obtain the flow field for fluids obeying the power-law model. The combined effects of the Reynolds number, the radius ratio, and the power-law index n on the flow characteristics are analyzed for an annular space of finite aspect ratio. Two flow modes are obtained: a primary Couette flow (CF) mode and a secondary Taylor vortex flow (TVF) mode. The flow structures so obtained are different from one mode to another. The critical Reynolds number Re(c) for the passage from the primary to the secondary mode exhibits the lowest value for the pseudoplastic fluids and the highest value for the dilatant fluids. The findings are useful for studies of the swirling flow of non-Newtonians fluids in axisymmetric geometries using LBM. The flow changes from the CF to TVF and its structure switches from the two-cells to four-cells regime for both Newtonian and dilatant fluids. Contrariwise for pseudoplastic fluids, the flow exhibits 2-4-2 structure passing from two-cells to four cells and switches again to the two-cells configuration. Furthermore, the critical Reynolds number presents a monotonic increase with the power-law index n of the non-Newtonian fluid, and as the radius ratio grows, the transition flow regimes tend to appear for higher critical Reynolds numbers. PMID:23767615

  1. Long-range forces affecting equilibrium inertial focusing behavior in straight high aspect ratio microfluidic channels

    NASA Astrophysics Data System (ADS)

    Reece, Amy E.; Oakey, John

    2016-04-01

    The controlled and directed focusing of particles within flowing fluids is a problem of fundamental and technological significance. Microfluidic inertial focusing provides passive and precise lateral and longitudinal alignment of small particles without the need for external actuation or sheath fluid. The benefits of inertial focusing have quickly enabled the development of miniaturized flow cytometers, size-selective sorting devices, and other high-throughput particle screening tools. Straight channel inertial focusing device design requires knowledge of fluid properties and particle-channel size ratio. Equilibrium behavior of inertially focused particles has been extensively characterized and the constitutive phenomena described by scaling relationships for straight channels of square and rectangular cross section. In concentrated particle suspensions, however, long-range hydrodynamic repulsions give rise to complex particle ordering that, while interesting and potentially useful, can also dramatically diminish the technique's effectiveness for high-throughput particle handling applications. We have empirically investigated particle focusing behavior within channels of increasing aspect ratio and have identified three scaling regimes that produce varying degrees of geometrical ordering between focused particles. To explore the limits of inertial particle focusing and identify the origins of these long-range interparticle forces, we have explored equilibrium focusing behavior as a function of channel geometry and particle concentration. Experimental results for highly concentrated particle solutions identify equilibrium thresholds for focusing that scale weakly with concentration and strongly with channel geometry. Balancing geometry mediated inertial forces with estimates for interparticle repulsive forces now provide a complete picture of pattern formation among concentrated inertially focused particles and enhance our understanding of the fundamental limits of

  2. Adrenocorticotrophic hormone and dexamethasone failed to affect milk yield in dairy goats: comparative aspects.

    PubMed

    Shamay; Mabjeesh; Shapiro; Silanikove

    2000-11-01

    The ability of adrenocorticotrophic hormone (ACTH; single i.v. injection of 2.5IU/kg BW) and dexamethasone (single i.m. injection of 36mg/kg BW) to affect milk production was studied in mid-lactating Israeli Saanen goats. None of these treatments produced changes in milk yield and composition of the goats. The effects of ACTH on blood cortisol levels, and the effects of ACTH and dexamethasone on blood plasma concentrations of glucose, however, were consistent with previous reports in goats and cows. These responses suggest that ACTH and dexamethasone treatments produced their expected glucocorticoid effects. It is suggested that obstructing the axis: stress-ACTH-glucocorticoid-down regulation of milk yield, which was demonstrated in dairy cows, reflects the adaptation of goats to harsh conditions, and the selection pressure to produce milk under conditions which are considered stressful for other ruminants. PMID:11024343

  3. Quality and safety aspects of meat products as affected by various physical manipulations of packaging materials.

    PubMed

    Lee, Keun Taik

    2010-09-01

    This article explores the effects of physically manipulated packaging materials on the quality and safety of meat products. Recently, innovative measures for improving quality and extending the shelf-life of packaged meat products have been developed, utilizing technologies including barrier film, active packaging, nanotechnology, microperforation, irradiation, plasma and far-infrared ray (FIR) treatments. Despite these developments, each technology has peculiar drawbacks which will need to be addressed by meat scientists in the future. To develop successful meat packaging systems, key product characteristics affecting stability, environmental conditions during storage until consumption, and consumers' packaging expectations must all be taken into consideration. Furthermore, the safety issues related to packaging materials must also be taken into account when processing, packaging and storing meat products.

  4. Targeting the affective and cognitive aspects of chronic neuropathic pain using basal forebrain neuromodulation: rationale, review and proposal.

    PubMed

    Oluigbo, Chima O; Salma, Asem; Rezai, Ali R

    2012-09-01

    Chronic pain is a major health problem in developed countries where it may affect as much as 20% of the adult population. There have been no significant clinical breakthroughs in therapeutic options for persons with chronic neuropathic pain. These limitations underscore the importance of developing new therapies for this disabling pain syndrome. We have reviewed the limitations of the present treatment strategies for chronic pain, neurophysiology of somatosensory transmission and nociception, mechanisms of neuropathic pain, the concept of a "pain matrix" and the "top-down" modulation of pain, and the cognitive affective role in processing of the pain experience. We found that affective and cognitive aspects of pain constitute important considerations in achieving improvements in the outcomes of pain neuromodulation in patients with chronic neuropathic pain. Based on our review, we propose that future novel neuromodulatory therapeutic strategies should be directed at areas in the brain that are involved in the neural mechanisms of reward valuation and appetitive motivation such as nucleus accumbens, ventral tegmental area, and prefrontal cortex.

  5. Theoretical, numerical and experimental study of geometrical parameters that affect anisotropy measurements in polarization-resolved SHG microscopy.

    PubMed

    Teulon, Claire; Gusachenko, Ivan; Latour, Gaël; Schanne-Klein, Marie-Claire

    2015-04-01

    Polarization-resolved second harmonic generation (P-SHG) microscopy is an efficient imaging modality for in situ observation of biopolymers structure in tissues, providing information about their mean in-plane orientation and their molecular structure and 3D distribution. Nevertheless, P-SHG signal build-up in a strongly focused regime is not throroughly understood yet, preventing reliable and reproducible measurements. In this study, theoretical analysis, vectorial numerical simulations and experiments are performed to understand how geometrical parameters, such as excitation and collection numerical apertures and detection direction, affect P-SHG imaging in homogeneous collagen tissues. A good agreement is obtained in tendon and cornea, showing that detection geometry significantly affects the SHG anisotropy measurements, but not the measurements of collagen in-plane orientation. PMID:25968762

  6. The impact of cognitive and affective aspects of cognitive conflict on learners' conceptual change about floating and sinking

    NASA Astrophysics Data System (ADS)

    Hadjiachilleos, Stella; Valanides, Nicos; Angeli, Charoula

    2013-07-01

    Background: Cognitive conflict has been identified as an important factor for bringing about students' conceptual change. Researchers draw attention to the need to study not only cognitive factors related to cognitive conflict but affective factors as well. Purpose: The purpose of this study was to investigate the contribution of cognitive and non-cognitive aspects involved in cognitive conflict on students' conceptual change. Sample: Fifteen students, five from each of fourth, sixth and eighth grades, participated in the study. Seven students were male, and the rest were female. All students had high academic performance and were good at explaining their reasoning. Design and method: The study focused on gaining in-depth information, using semi-structured clinical interviews, about students' thinking when they were engaged in an inquiry process, which incorporated cognitive conflict using a scenario about floating and sinking. Students' initial conceptions related to the phenomenon of floating and sinking were first diagnosed and, subsequently, discrepant events were presented to challenge their initial conceptions. The 15 interviews were qualitatively analyzed using the constant comparative analysis method. Results: The results of this study showed that students' conceptual change was directly related to both cognitive and affective aspects of cognitive conflict. The results also showed that some students showed persistence on alternative frameworks even after their exposure to cognitive conflict. Conclusions: Cognitive conflict is an idiosyncratic, or personal event, that may not be experienced by all learners in the same way. Thus, the effect of cognitive conflict on learners' conceptual change is directly related to learners' ability to experience and feel the conflict when it is presented to them.

  7. Passive solar in Milton Keynes, England. A description of some of the more numerical aspects of the design of an estate of low energy houses

    NASA Astrophysics Data System (ADS)

    Everett, R.

    1980-07-01

    The numerical aspects of the design of low energy consumption houses using passive solar energy collection and high levels of insulation are described. Two housing energy conservation projects were begun, one involving the construction of 177 low energy houses on a cost-effective basis, and the other involving the detailed monitoring of eight highly insulated passive solar houses. Both experimental data and theoretical analysis are presented, and the relative effectiveness of the various design alternatives are discussed.

  8. Flow around an individual morphologically complex plant: investigating the role of plant aspect in the numerical prediction of complex river flow

    NASA Astrophysics Data System (ADS)

    Boothroyd, R.; Hardy, R. J.; Warburton, J.; Marjoribanks, T.

    2015-12-01

    Aquatic vegetation has a significant influence on the hydraulic functioning of river systems. Plant morphology has previously been shown to alter the mean and turbulent properties of flow, influenced by the spatial distribution of branches and foliage, and these effects can be further investigated through numerical models. We report on a novel method for the measurement and incorporation of complex plant morphologies into a computational fluid dynamics (CFD) model. The morphological complexity of Prunus laurocerasus is captured under foliated and defoliated states through terrestrial laser scanning (TLS). Point clouds are characterised by a voxelised representation and incorporated into a CFD scheme using a mass flux scaling algorithm, allowing the numerical prediction of flows around individual plants. Here we examine the sensitivity of plant aspect, i.e. the positioning of the plant relative to the primary flow direction, by rotating the voxelised plant representation through 15° increments (24 rotations) about the vertical axis. This enables the impact of plant aspect to be quantified upon the velocity and pressure fields, and in particular how this effects species-specific drag forces and drag coefficients. Plant aspect is shown to considerably influence the flow field response, producing spatially heterogeneous downstream velocity fields with both symmetric and asymmetric wake shapes, and point of reattachments that extend up to seven plant lengths downstream. For the same plant, changes in aspect are shown to account for a maximum variation in drag force of 168%, which equates to a 65% difference in the drag coefficient. An explicit consideration of plant aspect is therefore important in studies concerning flow-vegetation interactions, especially when reducing the uncertainty in parameterising the effect of vegetation in numerical models.

  9. Internal energy flows of coma-affected singular beams in low-numerical-aperture systems.

    PubMed

    Bahl, Monika; Singh, Brijesh Kumar; Singh, Rakesh Kumar; Senthilkumaran, P

    2015-04-01

    The circulating phase gradient component of a singular beam gets modified when focused by a low-numerical-aperature system suffering from coma aberration. The gradient due to this coma aberration splits the higher charge vortex into elementary vortices and distributes them spatially. This splitting depends on the charge and polarity of the incident singular beam as well as the sign and magnitude of the aberration coefficient. The transverse component of the Poynting vector field distribution at the focal plane is decomposed into the curl or solenoidal component and divergence or irrotational component using the Helmholtz-Hodge decomposition technique. The solenoidal component that relates to the orbital angular momentum carries the circulating energy, while the irrotational component shows the sources and sinks of the energy. Intriguing results of the study of energy flow around the edge dislocations apart from the point phase defects in the irrotational components are also presented.

  10. Landfast ice affects the stability of the Arctic halocline: Evidence from a numerical model

    NASA Astrophysics Data System (ADS)

    Itkin, Polona; Losch, Martin; Gerdes, Rüdiger

    2015-04-01

    Landfast ice covers large surface areas of the winter Siberian Seas. The immobile landfast ice cover inhibits divergent and convergent motion, hence dynamical sea ice growth and redistribution, decouples winter river plumes in coastal seas from the atmosphere, and positions polynyas at the landfast ice edge offshore. In spite of the potentially large effects, state-of-the-art numerical models usually do not represent landfast ice in its correct extent. A simple parametrization of landfast ice based on bathymetry and internal sea ice strength is introduced and its effects on the simulated Arctic Ocean are demonstrated. The simulations suggest that the Siberian landfast ice impacts the Arctic halocline stability through enhanced brine production in polynyas located closer to the shelf break and by redirecting river water to the Canadian Basin. These processes strengthen the halocline in the Canadian Basin, but erode its stability in the Makarov and Eurasian Basins.

  11. Numerical modeling of multiple nitrate sources affecting the groundwater quality of private wells

    NASA Astrophysics Data System (ADS)

    Ballard, J.; Lefebvre, R.; Paradis, D.; Savard, M.

    2009-05-01

    The use of hydraulic data alone has proven to be insufficient to constrain transient simulations of mass transport. Recent developments in analytical methods, especially in the measurement of stable isotopes in water, have opened new possibilities to interpret transient groundwater flow and mass transport mechanisms. In that perspective, a numerical model was developed to represent the transient transport of nitrates in the Wilmot River watershed in Prince Edwards Island. This area is characterized by intensive agricultural land use, especially potato crops using large quantities of chemical fertilizers. The groundwater quality in many wells in the watershed has been deteriorating over the years, with the average nitrate concentration now reaching 7 mg/L, while some individual wells are above the maximum concentration limit of 10 mg/L. To evaluate the contribution of different nitrate sources to groundwater, seasonal concentrations of nitrate ion isotopes were measured in groundwater (N-15 and O-18). The dual isotope analysis allows the quantification of the proportions of nitrate species in groundwater, providing a geochemical mixing model of the different nitrate sources. The isotopic results obtained from the domestic wells within the watershed were used to develop and constrain a 3D groundwater flow and transport regional numerical model. Conceptually, the model reproduces the flow and transport conditions of the fractured upper 20 m of the aquifer. Since this part of the aquifer contains most the water available for domestic use, simulation results demonstrate that this groundwater is highly vulnerable to surface contamination and responds rapidly to changes in contaminant input.

  12. Numerical aspects of drift kinetic turbulence: ill-posedness, regularization and a priori estimates of sub-grid-scale terms

    NASA Astrophysics Data System (ADS)

    Samtaney, Ravi

    2012-01-01

    We present a numerical method based on an Eulerian approach to solve the Vlasov-Poisson system for 4D drift kinetic turbulence. Our numerical approach uses a conservative formulation with high-order (fourth and higher) evaluation of the numerical fluxes coupled with a fourth-order accurate Poisson solver. The fluxes are computed using a low-dissipation high-order upwind differencing method or a tuned high-resolution finite difference method with no numerical dissipation. Numerical results are presented for the case of imposed ion temperature and density gradients. Different forms of controlled regularization to achieve a well-posed system are used to obtain convergent resolved simulations. The regularization of the equations is achieved by means of a simple collisional model, by inclusion of an ad-hoc hyperviscosity or artificial viscosity term or by implicit dissipation in upwind schemes. Comparisons between the various methods and regularizations are presented. We apply a filtering formalism to the Vlasov equation and derive sub-grid-scale (SGS) terms analogous to the Reynolds stress terms in hydrodynamic turbulence. We present a priori quantifications of these SGS terms in resolved simulations of drift-kinetic turbulence by applying a sharp filter.

  13. Self-cleaning in an estuarine area formerly affected by 226Ra anthropogenic enhancements: numerical simulations.

    PubMed

    Periáñez, R; Absi, A; Villa, M; Moreno, H P; Manjón, G

    2005-03-01

    A numerical model of the Odiel-Tinto estuary (Spain) has been developed to study the self-cleaning process that was evidenced from 226Ra measurements in water and sediments collected in the period 1999-2002, after direct releases from a fertilizer complex ceased (in 1998). The hydrodynamic model is first calibrated, and standard tidal analysis is carried out to calculate tidal constants required by the dispersion code to determine instantaneous water currents and elevations over the estuary. In this way, long-term simulations may be carried out. The dispersion code includes advective/diffusive transport of radionuclides plus exchanges with bottom sediments described through a kinetic approach. The dispersion model is first tested by comparing computed and measured 226Ra concentrations over the estuary resulting after releases in the Odiel and Tinto rivers. Next, it is applied to simulate the self-cleaning process of the estuary. The time evolution of radium concentrations in bed sediments is in generally good agreement with observations. The computed sediment halving time of the estuary is 510 days, which also is in good agreement with that estimated from measurements.

  14. Plaque components affect wall stress in stented human carotid artery: A numerical study

    NASA Astrophysics Data System (ADS)

    Fan, Zhen-Min; Liu, Xiao; Du, Cheng-Fei; Sun, An-Qiang; Zhang, Nan; Fan, Zhan-Ming; Fan, Yu-Bo; Deng, Xiao-Yan

    2016-09-01

    Carotid artery stenting presents challenges of in-stent restenosis and late thrombosis, which are caused primarily by alterations in the mechanical environment of the artery after stent implantation. The present study constructed patient-specific carotid arterial bifurcation models with lipid pools and calcified components based on magnetic resonance imaging. We numerically analyzed the effects of multicomponent plaques on the distributions of von Mises stresses (VMSs) in the patient-specific models after stenting. The results showed that when a stent was deployed, the large soft lipid pool in atherosclerotic plaques cushioned the host artery and reduced the stress within the arterial wall; however, this resulted in a sharp increase of VMS in the fibrous cap. When compared with the lipid pool, the presence of the calcified components led to slightly increased stresses on the luminal surface. However, when a calcification was located close to the luminal surface of the host artery and the stenosis, the local VMS was elevated. Overall, compared with calcified components, large lipid pools severely damaged the host artery after stenting. Furthermore, damage due to the calcified component may depend on location.

  15. Numerous Numerals.

    ERIC Educational Resources Information Center

    Henle, James M.

    This pamphlet consists of 17 brief chapters, each containing a discussion of a numeration system and a set of problems on the use of that system. The numeration systems used include Egyptian fractions, ordinary continued fractions and variants of that method, and systems using positive and negative bases. The book is informal and addressed to…

  16. Numerical design of X-ray tabletop Talbot interferometer using polycapillary optics as two-dimensional gratings with high aspect ratio

    NASA Astrophysics Data System (ADS)

    Sun, Weiyuan; Liu, Zhiguo; Sun, Tianxi; Sun, Xuepeng; Li, Fangzuo; Jiang, Bowen; Ding, Xunliang

    2015-12-01

    The polycapillary optics was proposed to be used as two-dimensional X-ray gratings with high aspect ratios for high energy X-rays. The X-ray Talbot interferometer was designed numerically using the polycapillary X-ray gratings and a conventional X-ray source. The simulation showed that it was available to get a high-aspect-ratio pattern of the polycapillary X-ray gratings for higher energies than 60 keV. Moreover, this design of polycapillary gratings decreased the requirement for high power of the X-ray source. The polycapillary X-ray gratings had potential applications in X-ray imaging technology for medical fields, industrial nondestructive tests, public security, physical science, chemical analysis, life science, nanoscience biology and energy science.

  17. Does Grammatical Aspect Affect Motion Event Cognition? A Cross-Linguistic Comparison of English and Swedish Speakers

    ERIC Educational Resources Information Center

    Athanasopoulos, Panos; Bylund, Emanuel

    2013-01-01

    In this article, we explore whether cross-linguistic differences in grammatical aspect encoding may give rise to differences in memory and cognition. We compared native speakers of two languages that encode aspect differently (English and Swedish) in four tasks that examined verbal descriptions of stimuli, online triads matching, and memory-based…

  18. Experimental and Numerical Investigation on the Phase Separation Affected by Cooling Rates and Marangoni Convection in Cu-Cr Alloys

    NASA Astrophysics Data System (ADS)

    Wang, Fei; von Klinski-Wetzel, Katharina; Mukherjee, Rajdip; Nestler, Britta; Heilmaier, Martin

    2015-04-01

    In this work, we study the microstructures upon rapid solidification from the melt which occurs in Cu-Cr electrical contacts after switching operations. As the local cooling rates are difficult to be determined experimentally, we numerically compute the mean radius of Cr-particles from phase separation as a function of the cooling rate by utilizing a convective Cahn-Hilliard model. Based on the computationally derived correlation and on the metallographically observed microstructure, we are able to extract back the local cooling rates during heat treatment. We further examine the effect of Marangoni convection on the phase separation structure in a particularly composed simulation study. We obtain the cooling rate for a given particle size affected by the solutal Marangoni convection.

  19. Numerical power balance and free energy loss analysis for solar cells including optical, thermodynamic, and electrical aspects

    SciTech Connect

    Greulich, Johannes Höffler, Hannes; Würfel, Uli; Rein, Stefan

    2013-11-28

    A method for analyzing the power losses of solar cells is presented, supplying a complete balance of the incident power, the optical, thermodynamic, and electrical power losses and the electrical output power. The involved quantities have the dimension of a power density (units: W/m{sup 2}), which permits their direct comparison. In order to avoid the over-representation of losses arising from the ultraviolet part of the solar spectrum, a method for the analysis of the electrical free energy losses is extended to include optical losses. This extended analysis does not focus on the incident solar power of, e.g., 1000 W/m{sup 2} and does not explicitly include the thermalization losses and losses due to the generation of entropy. Instead, the usable power, i.e., the free energy or electro-chemical potential of the electron-hole pairs is set as reference value, thereby, overcoming the ambiguities of the power balance. Both methods, the power balance and the free energy loss analysis, are carried out exemplarily for a monocrystalline p-type silicon metal wrap through solar cell with passivated emitter and rear (MWT-PERC) based on optical and electrical measurements and numerical modeling. The methods give interesting insights in photovoltaic (PV) energy conversion, provide quantitative analyses of all loss mechanisms, and supply the basis for the systematic technological improvement of the device.

  20. Numerical power balance and free energy loss analysis for solar cells including optical, thermodynamic, and electrical aspects

    NASA Astrophysics Data System (ADS)

    Greulich, Johannes; Höffler, Hannes; Würfel, Uli; Rein, Stefan

    2013-11-01

    A method for analyzing the power losses of solar cells is presented, supplying a complete balance of the incident power, the optical, thermodynamic, and electrical power losses and the electrical output power. The involved quantities have the dimension of a power density (units: W/m2), which permits their direct comparison. In order to avoid the over-representation of losses arising from the ultraviolet part of the solar spectrum, a method for the analysis of the electrical free energy losses is extended to include optical losses. This extended analysis does not focus on the incident solar power of, e.g., 1000 W/m2 and does not explicitly include the thermalization losses and losses due to the generation of entropy. Instead, the usable power, i.e., the free energy or electro-chemical potential of the electron-hole pairs is set as reference value, thereby, overcoming the ambiguities of the power balance. Both methods, the power balance and the free energy loss analysis, are carried out exemplarily for a monocrystalline p-type silicon metal wrap through solar cell with passivated emitter and rear (MWT-PERC) based on optical and electrical measurements and numerical modeling. The methods give interesting insights in photovoltaic (PV) energy conversion, provide quantitative analyses of all loss mechanisms, and supply the basis for the systematic technological improvement of the device.

  1. Numerical and Experimental Aspects of Data Acquisition and Processing in Application to Temperature Resolved 3-D Sub-Millimeter Spectroscopy for Astrophysics and Spectral Assignment.

    NASA Astrophysics Data System (ADS)

    Medvedev, Ivan R.; Fortman, Sarah M.; Neese, Christopher F.; De Lucia, Frank C.

    2009-06-01

    Experimental determination of the lower state energy for every transition in molecular spectra, made possible by temperature resolved 3-D spectroscopy, opens new frontiers in our ability to predict molecular spectra over a wide range of temperatures and to assign rotational spectra in many vibrational states. Our improved collisional cooling cell design extends temperature coverage of this technique to 77 K. This enhances our ability to simulate molecular spectra at temperatures of astronomical relevance. We are reporting on experimental and numerical aspects of dealing with exceptionally high information content of these spectra. New data reduction algorithms allow us to process this data in timely fashion in an attempt to make them available to astronomical community.

  2. How the spatial position of individuals affects their influence on swarms: a numerical comparison of two popular swarm dynamics models.

    PubMed

    Kolpas, Allison; Busch, Michael; Li, Hong; Couzin, Iain D; Petzold, Linda; Moehlis, Jeff

    2013-01-01

    Schools of fish and flocks of birds are examples of self-organized animal groups that arise through social interactions among individuals. We numerically study two individual-based models, which recent empirical studies have suggested to explain self-organized group animal behavior: (i) a zone-based model where the group communication topology is determined by finite interacting zones of repulsion, attraction, and orientation among individuals; and (ii) a model where the communication topology is described by Delaunay triangulation, which is defined by each individual's Voronoi neighbors. The models include a tunable parameter that controls an individual's relative weighting of attraction and alignment. We perform computational experiments to investigate how effectively simulated groups transfer information in the form of velocity when an individual is perturbed. A cross-correlation function is used to measure the sensitivity of groups to sudden perturbations in the heading of individual members. The results show how relative weighting of attraction and alignment, location of the perturbed individual, population size, and the communication topology affect group structure and response to perturbation. We find that in the Delaunay-based model an individual who is perturbed is capable of triggering a cascade of responses, ultimately leading to the group changing direction. This phenomenon has been seen in self-organized animal groups in both experiments and nature. PMID:23555585

  3. Does fluid infiltration affect the motion of sediment grains? - A 3-D numerical modelling approach using SPH

    NASA Astrophysics Data System (ADS)

    Bartzke, Gerhard; Rogers, Benedict D.; Fourtakas, Georgios; Mokos, Athanasios; Huhn, Katrin

    2016-04-01

    The processes that cause the creation of a variety of sediment morphological features, e.g. laminated beds, ripples, or dunes, are based on the initial motion of individual sediment grains. However, with experimental techniques it is difficult to measure the flow characteristics, i.e., the velocity of the pore water flow in sediments, at a sufficient resolution and in a non-intrusive way. As a result, the role of fluid infiltration at the surface and in the interior affecting the initiation of motion of a sediment bed is not yet fully understood. Consequently, there is a strong need for numerical models, since these are capable of quantifying fluid driven sediment transport processes of complex sediment beds composed of irregular shapes. The numerical method Smoothed Particle Hydrodynamics (SPH) satisfies this need. As a meshless and Lagrangian technique, SPH is ideally suited to simulating flows in sediment beds composed of various grain shapes, but also flow around single grains at a high temporal and spatial resolution. The solver chosen is DualSPHysics (www.dual.sphysics.org) since this is validated for a range of flow conditions. For the present investigation a 3-D numerical flume model was generated using SPH with a length of 4.0 cm, a width of 0.05 cm and a height of 0.2 cm where mobile sediment particles were deposited in a recess. An experimental setup was designed to test sediment configurations composed of irregular grain shapes (grain diameter, D50=1000 μm). Each bed consisted of 3500 mobile objects. After the bed generation process, the entire domain was flooded with 18 million fluid particles. To drive the flow, an oscillating motion perpendicular to the bed was applied to the fluid, reaching a peak value of 0.3 cm/s, simulating 4 seconds of real time. The model results showed that flow speeds decreased logarithmically from the top of the domain towards the surface of the beds, indicating a fully developed boundary layer. Analysis of the fluid

  4. The Affect of Realistic Geologic Heterogeneity on Local and Regional P/S Amplitude Ratios Based on Numerical Simulations

    SciTech Connect

    Myers, S C; Wagoner, J L; Preston, L; Smith, K; Larsen, S C

    2005-07-11

    Regional seismic discriminants based on high-frequency P/S ratios reliably distinguish between earthquakes and explosions. However, P/S discriminants in the 0.5 to 3 Hz band (where SNR can be highest) rarely perform well, with similar ratios for earthquake and explosion populations. Variability in discriminant performance has spawned numerous investigations into the generation of S-waves from explosions. Several viable mechanisms for the generation of S-waves from explosions have been forwarded, but most of these mechanisms do not explain observations of frequency-dependant S-wave generation. Recent studies have focused on the affect of near-source scattering to explain the frequency-dependence of both S-wave generation and P/S discriminant performance. In this study we investigate near-source scatter through numerical simulation with a realistic geological model We have constructed a realistic, 3-dimensional earth model of the southern Basin and Range. This regional model includes detailed constraints at the Nevada Test Site (NTS) based on extensive geologic and geophysical studies. Gross structure of the crust and upper mantle is taken from regional surface-wave studies. Variations in crustal thickness are based on receiver function analysis and a compilation of reflection/refraction studies. Upper-crustal constraints are derived from geologic maps and detailed studies of sedimentary basin geometry throughout the study area. The free surface is based on a 10-meter digital elevation model (DEM) at NTS, and a 60-meter DEM elsewhere. The model extends to a depth of 150km, making it suitable for simulations at local and regional distances. Our simulation source is based on the 1993 Non-Proliferation Experiment explosion at the NTS. This shot was well recorded, offering ample validation data. Our validation tests include measures of long-period waveform fit and relative amplitude measurements for P and S phases. Our primary conclusion is that near-source topography

  5. Childhood depression and conduct disorder: I. Behavioral, affective, and cognitive aspects of family problem-solving interactions.

    PubMed

    Sanders, M R; Dadds, M R; Johnston, B M; Cash, R

    1992-08-01

    We assessed the family interactions of depressed, conduct-disordered, mixed depressed-conduct-disordered, and nonclinic children, ages 7-14 years, during a standardized family problem-solving discussion in the clinic. The child's and the mother's problem-solving proficiency, aversive behavior, and associated affective behavior (depressed and angry-hostile) were observed. The child and mother also rated each other's affect during the interaction for the dimensions sad, angry, critical, and happy on Likert-type scales. The child's and mother's cognitive constructions about the interaction were assessed using video-mediated recall. Although all clinic groups had lower levels of effective problem solving than did nonclinic children, their deficiencies were somewhat different. Mixed and depressed children displayed high levels of depressed affect and low levels of angry affect, whereas conduct-disordered children displayed both angry and depressed affect. In addition, conduct-disordered children had lower levels of positive problem solving and higher levels of aversive content than did non-conduct-disordered children. Depressed and conduct-disordered children had higher levels of self-referent negative cognitions than did mixed and comparison children, and depressed children also had higher other-referent negative cognitions than did all other groups. The study provides support for theories and treatment that stress the importance of family problem-solving and conflict resolution skills in child psychopathology.

  6. Numerical aspects and implementation of a two-layer zonal wall model for LES of compressible turbulent flows on unstructured meshes

    NASA Astrophysics Data System (ADS)

    Park, George Ilhwan; Moin, Parviz

    2016-01-01

    This paper focuses on numerical and practical aspects associated with a parallel implementation of a two-layer zonal wall model for large-eddy simulation (LES) of compressible wall-bounded turbulent flows on unstructured meshes. A zonal wall model based on the solution of unsteady three-dimensional Reynolds-averaged Navier-Stokes (RANS) equations on a separate near-wall grid is implemented in an unstructured, cell-centered finite-volume LES solver. The main challenge in its implementation is to couple two parallel, unstructured flow solvers for efficient boundary data communication and simultaneous time integrations. A coupling strategy with good load balancing and low processors underutilization is identified. Face mapping and interpolation procedures at the coupling interface are explained in detail. The method of manufactured solution is used for verifying the correct implementation of solver coupling, and parallel performance of the combined wall-modeled LES (WMLES) solver is investigated. The method has successfully been applied to several attached and separated flows, including a transitional flow over a flat plate and a separated flow over an airfoil at an angle of attack.

  7. Numerical Development

    ERIC Educational Resources Information Center

    Siegler, Robert S.; Braithwaite, David W.

    2016-01-01

    In this review, we attempt to integrate two crucial aspects of numerical development: learning the magnitudes of individual numbers and learning arithmetic. Numerical magnitude development involves gaining increasingly precise knowledge of increasing ranges and types of numbers: from non-symbolic to small symbolic numbers, from smaller to larger…

  8. [Caring for a person affected by Alzheimer's disease: specific aspects of grief in family caregivers and their social support].

    PubMed

    Malaquin-Pavan, Evelyne; Pierrot, Marylène

    2007-06-01

    Alzheimer's disease (DTA) leads to some behavioural, physical and psychic modifications in the patient that the natural helper (family-spouse-child) will have to face throughout the course of the disease. The authors have tried to identify the nature of losses experienced by helpers so as to bring out some preventive and curative support tracks. This preparatory research-action was conducted with 27 families through semi-directive conversations which enabled to reveal their difficulties (somatic-emotional-affective-organizational), their reactions of adaptation in echo with the losses of the patient along the course of the DTA as well as the elements enabling to maintain or not the ill person's family/close relation link. The analysis of obtained results is proposed according to the concepts of adaptation, affection and separation, systemic approach and coping. The comments and behaviours of helpers are put in relation with the symptoms of mourning as well as with the medical interactions, helper or not. Five chronological times were identified (before diagnosis-moment of the diagnosis-keeping at home-admission in institution-life in institution). The period of white mourning (connected to the loss of the recognition of his/her close relations by the patient) is mainly felt as a vector of suffering. As part of the dynamics of social support, the proposed tracks of nursing interventions mainly target the admission and life in institution; their aim is to offer an adapted support to natural helpers, whether they make the choice or not to support their close patients throughout the institutionalization. In appendices, all the key ideas helping to track down the elements contributing to maintain the ill person's helper/close relation link or accelerating his/her breaking down.

  9. Vitamin D depletion does not affect key aspects of the preeclamptic phenotype in a transgenic rodent model for preeclampsia.

    PubMed

    Andersen, Louise Bjørkholt; Golic, Michaela; Przybyl, Lukasz; Sorensen, Grith Lykke; Jørgensen, Jan Stener; Fruekilde, Palle; von Versen-Höynck, Frauke; Herse, Florian; Højskov, Carsten Schriver; Dechend, Ralf; Christesen, Henrik Thybo; Haase, Nadine

    2016-07-01

    Maternal vitamin D deficiency is proposed as a risk factor for preeclampsia in humans. We tested the hypothesis that vitamin D depletion aggravates and high supplementation ameliorates the preeclampsia phenotype in an established transgenic rat model of human renin-angiotensin system-mediated preeclampsia. Adult rat dams, transgenic for human angiotensinogen (hAGT) and mated with male rats transgenic for human renin (hREN), were fed either vitamin D-depleted chow (VDd) or enriched chow (VDh) 2 weeks before mating and during pregnancy. Mean blood pressure was recorded by tail-cuff, and 24-hour urine samples were collected in metabolic cages at days 6 and 18 of gestation. Rats were sacrificed at day 21 of gestation. Depleted dams (VDd) had negligible serum 25-hydroxyvitamin D2+3 levels (mean ± SEM; 2.95 ± 0.45 nmol/l vs. VDh 26.20 ± 2.88 nmol/l, P = .01), but in both groups, levels of 1,25(OH)2D3 remained below detection level of 25 pmol/l. Dietary vitamin D depletion did not aggravate hypertension (mean ± SEM BP, day 20 of gestation: 151.38 ± 5.65 mmHg VDd vs. 152.00 ± 4.10 mmHg VDh) or proteinuria. Fetal anthropometrics were similar between the groups, whereas VDd displayed lower placental:fetal weight ratios (0.15 vs. 0.16 g/g, P = .01) and increased sFlt-1/PlGF ratio. Expression of hREN was lower in placenta of VDd dams (0.82 ± 0.44 AU vs. 1.52 ± 0.15 AU, P = .04). Expression of key vitamin D metabolizing enzymes was unchanged. Dietary vitamin D intervention did not alter key aspects of the preeclampsia phenotype using the transgenic rodent model of human renin-angiotensin system-mediated pre-eclampsia, plausibly due to altered vitamin D metabolism or excretion in the transgenic rats. PMID:27450577

  10. How the negative and positive aspects of partner relationships affect the mental health of young married people.

    PubMed

    Horwitz, A V; McLaughlin, J; White, H R

    1998-06-01

    The relationship between marriage and positive mental health is one of the most established findings in the stress literature. Few studies, however, examine the problematic as well as the supportive impacts of marriage on mental health. This paper uses a cohort of young adults who were sampled at 18, 21, or 24 years of age and resampled seven years later when they were married at 25, 28, or 31. It examines what factors are associated with the quality of marital relationships, the relative impact of and balance between negative and positive partner relationships on mental health, and sex differences in the determinants and outcomes of marital quality. The results indicate that the structural strains of parenthood and financial need and their interaction predict problematic and supportive spousal relationships and the difference in the levels of these two relationships. Problematic relationships with spouses have considerably stronger impacts than supportive relationships on depression. However, the difference between the amounts of supportive and problematic relationships with spouses has a greater impact on mental health than levels of either considered separately. Finally, relational quality has a greater impact on the mental health of wives than husbands. These findings indicate the importance of considering how marriage affects mental health in complex, rather than in straightforward, ways.

  11. Verbal versus Numerical Probabilities: Does Format Presentation of Probabilistic Information regarding Breast Cancer Screening Affect Women's Comprehension?

    ERIC Educational Resources Information Center

    Vahabi, Mandana

    2010-01-01

    Objective: To test whether the format in which women receive probabilistic information about breast cancer and mammography affects their comprehension. Methods: A convenience sample of 180 women received pre-assembled randomized packages containing a breast health information brochure, with probabilities presented in either verbal or numeric…

  12. The Vasto Landslide (Adriatic coast, central Italy): geomorphological constraints and numerical modelling to reconstruct the evolution of a large instability affecting a coastal slope

    NASA Astrophysics Data System (ADS)

    Della Seta, M.; Martino, S.; Scarascia Mugnozza, G.

    2012-04-01

    The Vasto town (Abruzzi, central Italy) raises 143 m a.s.l., on the top of an uplifted Quaternary regressive sequence. The coastal slope is affected by large slope instability (Vasto Landslide) with evidence of present activity, as suggested by several geomorphic features. Well documented historical disruptive events affected the town and the coastal slope in 1816, 1942 and 1956, with deformation locally reaching the near offshore. Field morpho-stratigraphic evidences suggest that sea cliff retreat must have removed considerable volumes of rock before the first activation of the large slope instability. Thus, a morpho-evolutive model of the Vasto Landslide is proposed here, which takes into account the present landforms, the field geological evidences as well as borehole stratigraphy and the combined effect of Quaternary uplift and eustatic oscillations on the coastal slope, since the area started emerging (early Middle Pleistocene) and up to present. Some significant steps were identified, given the tectono-eustatic constraints, and slope stability was analysed with the method of slices (Fellenius) for the different steps. The analysis confirms the kinematic consistency of the first activation of two major roto-translational surfaces in the Middle Pleistocene, after considerable sea cliff retreat. Finite difference stress-strain numerical modelling (FDM) of the Vasto Landslide was then performed in order to output: 1) the landslide mechanism; 2) the style of activity of the landslide; 3) the cumulative deformations occurred during the morpho-evolutive steps. The numerical modelling was calibrated by considering the present landforms as well as the effects recorded during the historical events. The results obtained here confirm that the Vasto Lanslide was first activated in the Middle Pleistocene (~200 ka B.P.), as a consequence of wave cut erosion and progressive emersion of the coastal slope. Moreover, the landslide evolved as a retrogressive, single

  13. Role of α7- and β4-containing nicotinic acetylcholine receptors in the affective and somatic aspects of nicotine withdrawal: studies in knockout mice.

    PubMed

    Stoker, Astrid K; Olivier, Berend; Markou, Athina

    2012-05-01

    To assess which nicotinic acetylcholine receptors (nAChRs) are involved in the aversive aspects of nicotine withdrawal, brain reward function and the somatic signs of nicotine withdrawal were assessed in mice that lack α7 and β4 nAChR subunits. Brain reward function was assessed with the intracranial self-stimulation (ICSS) procedure, in which elevations in ICSS thresholds reflect an anhedonic mood state. At 3-6 h of spontaneous nicotine/saline withdrawal, thresholds were elevated in nicotine-withdrawing α7(+/+) and β4(+/+), but not α7(-/-) or β4(-/-), mice compared with saline-withdrawing mice, indicating a delay in the onset of withdrawal in the knockout mice. From 8 to 100 h of withdrawal, thresholds in α7(+/+) and α7(-/-) mice were equally elevated, whereas thresholds in β4(+/+) and β4(-/-) mice returned to baseline levels. Somatic signs were attenuated in nicotine-withdrawing β4(-/-), but not α7(-/-), mice. Administration of a low dose of the nAChR antagonist mecamylamine induced threshold elevations in α7(-/-), but not α7(+/+), mice, whereas the highest dose tested only elevated thresholds in α7(+/+) mice. Mecamylamine-induced threshold elevations were similar in β4(-/-) and β4(+/+) mice. In conclusion, null mutation of the α7 and β4 nAChR subunits resulted in a delayed onset of the anhedonic aspects of the spontaneous nicotine withdrawal syndrome. Previous findings of attenuated somatic signs of nicotine withdrawal in β4(-/-), but not α7(-/-), mice were confirmed in the present study, indicating an important role for β4-containing nAChRs in the somatic signs of nicotine withdrawal. The mecamylamine-precipitated withdrawal data suggest that compensatory adaptations may occur in constitutive α7(-/-) mice or that mecamylamine may interact with other receptors besides nAChRs in these mice. In summary, the present results indicate an important role for α7 and β4-containing nAChRs in the anhedonic or somatic signs of nicotine withdrawal.

  14. [The pathogenic aspects of fat acids metabolism with short chain and production of cytokines in target affected areas of skin under psoriasis].

    PubMed

    fal'ko, E V; Khyshiktuev, B S; Karavaeva, T M; Tereshkov, P P; Gomboeva, A Ts

    2012-01-01

    The article deals with the results of analysis of specters of short-chained fat acids and cytokines in affected skin of patients with psoriasis. The study revealed the significant decrease of short-chained fat acids level, the shift of cytokine profile in the direction of anti-inflammatory factors (interleukins 1L-1beta, IL-8, tumor necrosis factor TNF-alpha, interferon IFN-alpha) and mytogenetic factors (EGF) on the background of stable values of anti-inflammatory cytokine IL-4. The direct pathogenically significant correlation relationships are established between the IL-4 level and the amount of most analyzed short-chained fat acids. The negative correlation relationships were established between content of C2 and IL-1beta.

  15. Frequency-dependent numerical dynamics in mosquitofish.

    PubMed Central

    Horth, Lisa; Travis, Joseph

    2002-01-01

    Altering the genetic composition of a population can alter several aspects of its numerical dynamics. Whether natural populations routinely contain the genetic variation capable of affecting the stability of those dynamics is less clear. Here we report a study of experimental populations of mosquitofish (Gambusia holbrooki), designed to examine this issue. The experiment examined the numerical effects of varying the initial relative frequency of a rare male genotype. A higher relative frequency of the rare, melanic genotype produced higher mortality rates in melanic males, higher mortality rates in females, higher juvenile abundance, and fewer fluctuations in the numbers of females across time. This work demonstrates that a natural population can harbour genetic variants in a single gender that are capable of inducing qualitative differences in the numerical dynamics of the opposite gender, through the effects of negative frequency-dependent selection. PMID:12427317

  16. [Pulmonary Echinococcosis: Surgical Aspects].

    PubMed

    Eichhorn, M E; Hoffmann, H; Dienemann, H

    2015-10-01

    Pulmonary cystic echinococcosis is a very rare disease in Germany. It is caused by the larvae of the dog tapeworm (echinococcus granulosus). The liver is the most affected organ, followed by the lungs. Surgery remains the main therapeutic approach for pulmonary CE. Whenever possible, parenchyma-preserving lung surgery should be preferred over anatomic lung resections. To ensure best therapeutic results, surgery needs to be performed under precise consideration of important infectiological aspects and patients should be treated in specialised centres based on interdisciplinary consensus. In addition to surgical aspects, this review summarises special infectiological features of this disease, which are crucial to the surgical approach. PMID:26351761

  17. How does gully recharge affect sediment transfers by debris flows? A numerical modelling study in steep mountainous terrain, coastal British Columbia

    NASA Astrophysics Data System (ADS)

    Martin, Y. E.; Johnson, E. A.; Chaikina, O.

    2014-12-01

    Debris flows are a major process responsible for transferring sediment from high mountain locations to more downstream fluvial reaches. This sediment transfer begins on mountain hillslopes where various mass wasting processes move sediment from hillslopes to uppermost reaches of the channel system (these reaches are herein referred to as gullies and only experience water flow during high intensity precipitation events). Sediment recharge into gullies, which has received minimal attention in the scientific literature, refers to the transfer of sediment and other debris from surrounding hillslopes into gullies (Jakob and Oden, 2005). Debris flow occurrence and debris flow volumes depend on some precipitation threshold as well as volumes of material contained in the particular gully. For example, if one debris flow has removed all of the accumulated material from the gully, then any subsequent debris flow will be smaller if enough time has not yet passed for notable sediment recharge. Herein, we utilize the numerical model of landscape development, LandMod (Martin, 1998; Dadson and Church, 2005; Martin, 2007), to explore connections between hillslope processes, gully recharge rates, and transfer of sediment to downstream channel reaches in the Haida Gwaii, British Columbia. Hillslope processes in the model include shallow landsliding, bedrock failures and weathering. The updated debris flow algorithm is based on extensive field data available for debris flows in Haida Gwaii (e.g., Rood, 1984; Oden, 1994; Jakob and Oden, 2005), as well as theoretical considerations based on debris flow studies. The most significant model extension is the calculation of gully recharge rates; for each gully, the total accumulated sediment in gullies at each time step is determined using a power-law relation for area-normalized recharge rate versus elapsed time since the last debris flow. Thus, when the stochastic driver for debris flow occurrence triggers an event, the amount of stored

  18. Geometrical aspects of entanglement

    SciTech Connect

    Leinaas, Jon Magne; Myrheim, Jan; Ovrum, Eirik

    2006-07-15

    We study geometrical aspects of entanglement, with the Hilbert-Schmidt norm defining the metric on the set of density matrices. We focus first on the simplest case of two two-level systems and show that a 'relativistic' formulation leads to a complete analysis of the question of separability. Our approach is based on Schmidt decomposition of density matrices for a composite system and nonunitary transformations to a standard form. The positivity of the density matrices is crucial for the method to work. A similar approach works to some extent in higher dimensions, but is a less powerful tool. We further present a numerical method for examining separability and illustrate the method by a numerical study of bound entanglement in a composite system of two three-level systems.

  19. Regulatory aspects

    NASA Astrophysics Data System (ADS)

    Stern, Arthur M.

    1986-07-01

    At this time, there is no US legislation that is specifically aimed at regulating the environmental release of genetically engineered organisms or their modified components, either during the research and development stage or during application. There are some statutes, administered by several federal agencies, whose language is broad enough to allow the extension of intended coverage to include certain aspects of biotechnology. The one possible exception is FIFRA, which has already brought about the registration of several natural microbial pesticides but which also has provision for requiring the registration of “strain improved” microbial pesticides. Nevertheless, there may be gaps in coverage even if all pertinent statutes were to be actively applied to the control of environmental release of genetically modified substances. The decision to regulate biotechnology under TSCA was justified, in part, on the basis of its intended role as a gap-filling piece of environmental legislation. The advantage of regulating biotechnology under TSCA is that this statute, unlike others, is concerned with all media of exposure (air, water, soil, sediment, biota) that may pose health and environmental hazards. Experience may show that extending existing legislation to regulate biotechnology is a poor compromise compared to the promulgation of new legislation specifically designed for this purpose. It appears that many other countries are ultimately going to take the latter course to regulate biotechnology.

  20. Numerical nebulae

    NASA Astrophysics Data System (ADS)

    Rijkhorst, Erik-Jan

    2005-12-01

    The late stages of evolution of stars like our Sun are dominated by several episodes of violent mass loss. Space based observations of the resulting objects, known as Planetary Nebulae, show a bewildering array of highly symmetric shapes. The interplay between gasdynamics and radiative processes determines the morphological outcome of these objects, and numerical models for astrophysical gasdynamics have to incorporate these effects. This thesis presents new numerical techniques for carrying out high-resolution three-dimensional radiation hydrodynamical simulations. Such calculations require parallelization of computer codes, and the use of state-of-the-art supercomputer technology. Numerical models in the context of the shaping of Planetary Nebulae are presented, providing insight into their origin and fate.

  1. Numerical Relativity

    NASA Technical Reports Server (NTRS)

    Baker, John G.

    2009-01-01

    Recent advances in numerical relativity have fueled an explosion of progress in understanding the predictions of Einstein's theory of gravity, General Relativity, for the strong field dynamics, the gravitational radiation wave forms, and consequently the state of the remnant produced from the merger of compact binary objects. I will review recent results from the field, focusing on mergers of two black holes.

  2. Numerical Integration

    ERIC Educational Resources Information Center

    Sozio, Gerry

    2009-01-01

    Senior secondary students cover numerical integration techniques in their mathematics courses. In particular, students would be familiar with the "midpoint rule," the elementary "trapezoidal rule" and "Simpson's rule." This article derives these techniques by methods which secondary students may not be familiar with and an approach that…

  3. Symmetry aspects in stability investigations for thin membranes

    NASA Astrophysics Data System (ADS)

    Eriksson, Anders; Nordmark, Arne

    2016-08-01

    Modelling of structural instability problems is considered for thin square membranes subjected to hydrostatic pressure, with a focus on the effects from symmetry conditions considered or neglected in the model. An analysis is performed through group-theoretical concepts of the symmetry aspects present in a flat membrane with one-sided pressure loading. The response of the membrane is described by its inherent differential eigensolutions, which are shown to be of five different types with respect to symmetry. A discussion is given on how boundary conditions must be introduced in order to catch all types of eigensolutions when modelling only a subdomain of the whole. Lacking symmetry in a FEM model of the whole domain is seen as a perturbation to the problem, and is shown to affect the calculated instability response, hiding or modifying instability modes. Numerical simulations verify and illustrate the analytical results, and further show the convergence with mesh fineness of different aspects of instability results.

  4. Approaches to Numerical Relativity

    NASA Astrophysics Data System (ADS)

    d'Inverno, Ray

    2005-07-01

    Introduction Ray d'Inverno; Preface C. J. S. Clarke; Part I. Theoretical Approaches: 1. Numerical relativity on a transputer array Ray d'Inverno; 2. Some aspects of the characteristic initial value problem in numerical relativity Nigel Bishop; 3. The characteristic initial value problem in general relativity J. M. Stewart; 4. Algebraic approachs to the characteristic initial value problem in general relativity Jõrg Frauendiener; 5. On hyperboidal hypersurfaces Helmut Friedrich; 6. The initial value problem on null cones J. A. Vickers; 7. Introduction to dual-null dynamics S. A. Hayward; 8. On colliding plane wave space-times J. B. Griffiths; 9. Boundary conditions for the momentum constraint Niall O Murchadha; 10. On the choice of matter model in general relativity A. D. Rendall; 11. A mathematical approach to numerical relativity J. W. Barrett; 12. Making sense of the effects of rotation in general relativity J. C. Miller; 13. Stability of charged boson stars and catastrophe theory Franz E. Schunck, Fjodor V. Kusmartsev and Eckehard W. Mielke; Part II. Practical Approaches: 14. Numerical asymptotics R. Gómez and J. Winicour; 15. Instabilities in rapidly rotating polytropes Scott C. Smith and Joan M. Centrella; 16. Gravitational radiation from coalescing binary neutron stars Ken-Ichi Oohara and Takashi Nakamura; 17. 'Critical' behaviour in massless scalar field collapse M. W. Choptuik; 18. Goudunov-type methods applied to general relativistic gravitational collapse José Ma. Ibánez, José Ma. Martí, Juan A. Miralles and J. V. Romero; 19. Astrophysical sources of gravitational waves and neutrinos Silvano Bonazzola, Eric Gourgoulhon, Pawel Haensel and Jean-Alain Marck; 20. Gravitational radiation from triaxial core collapse Jean-Alain Marck and Silvano Bonazzola; 21. A vacuum fully relativistic 3D numerical code C. Bona and J. Massó; 22. Solution of elliptic equations in numerical relativity using multiquadrics M. R. Dubal, S. R. Oliveira and R. A. Matzner; 23

  5. Measuring Aspects of Morality

    ERIC Educational Resources Information Center

    Ziv, Avner

    1976-01-01

    A group test measuring five aspects of morality in children is presented. The aspects are: resistance to temptation, stage of moral judgment, confession after transgression, reaction of fear or guilt, and severity of punishment for transgression. (Editor)

  6. Perceptual aspects of singing.

    PubMed

    Sundberg, J

    1994-06-01

    The relations between acoustic and perceived characteristics of vowel sounds are demonstrated with respect to timbre, loudness, pitch, and expressive time patterns. The conditions for perceiving an ensemble of sine tones as one tone or several tones are reviewed. There are two aspects of timbre of voice sounds: vowel quality and voice quality. Although vowel quality depends mainly on the frequencies of the lowest two formants. In particular, the center frequency of the so-called singer's formant seems perceptually relevant. Vocal loudness, generally assumed to correspond closely to the sound pressure level, depends rather on the amplitude balance between the lower and the higher spectrum partials. The perceived pitch corresponds to the fundamental frequency, or for vibrato tones, the mean of this frequency. In rapid passages, such as coloratura singing, special patterns are used. Pitch and duration differences are categorically perceived in music. This means that small variations in tuning or duration do not affect the musical interval and the note value perceived. Categorical perception is used extensively in music performance for the purpose of musical expression because without violating the score, the singer may sharpen or flatten and lengthen or shorten the tones, thereby creating musical expression. PMID:8061767

  7. NUCLEAR PORE ANCHOR, the Arabidopsis Homolog of Tpr/Mlp1/Mlp2/Megator, Is Involved in mRNA Export and SUMO Homeostasis and Affects Diverse Aspects of Plant Development[W

    PubMed Central

    Xu, Xianfeng Morgan; Rose, Annkatrin; Muthuswamy, Sivaramakrishnan; Jeong, Sun Yong; Venkatakrishnan, Sowmya; Zhao, Qiao; Meier, Iris

    2007-01-01

    Vertebrate Tpr and its yeast homologs Mlp1/Mlp2, long coiled-coil proteins of nuclear pore inner basket filaments, are involved in mRNA export, telomere organization, spindle pole assembly, and unspliced RNA retention. We identified Arabidopsis thaliana NUCLEAR PORE ANCHOR (NUA) encoding a 237-kD protein with similarity to Tpr. NUA is located at the inner surface of the nuclear envelope in interphase and in the vicinity of the spindle in prometaphase. Four T-DNA insertion lines were characterized, which comprise an allelic series of increasing severity for several correlating phenotypes, such as early flowering under short days and long days, increased abundance of SUMO conjugates, altered expression of several flowering regulators, and nuclear accumulation of poly(A)+ RNA. nua mutants phenocopy mutants of EARLY IN SHORT DAYS4 (ESD4), an Arabidopsis SUMO protease concentrated at the nuclear periphery. nua esd4 double mutants resemble nua and esd4 single mutants, suggesting that the two proteins act in the same pathway or complex, supported by yeast two-hybrid interaction. Our data indicate that NUA is a component of nuclear pore-associated steps of sumoylation and mRNA export in plants and that defects in these processes affect the signaling events of flowering time regulation and additional developmental processes. PMID:17513499

  8. Dynamical aspects of an adiabatic piston.

    PubMed

    Munakata, T; Ogawa, H

    2001-09-01

    Dynamical aspects of an adiabatic piston are investigated, based on the mass ratio expansion of the master equation for the piston velocity distribution function. Simple theory for piston motion and relaxation of an ideal gas in a cylinder turns out to reproduce our numerical experiments quantitatively.

  9. Dynamical aspects of an adiabatic piston

    NASA Astrophysics Data System (ADS)

    Munakata, Toyonori; Ogawa, Hideki

    2001-09-01

    Dynamical aspects of an adiabatic piston are investigated, based on the mass ratio expansion of the master equation for the piston velocity distribution function. Simple theory for piston motion and relaxation of an ideal gas in a cylinder turns out to reproduce our numerical experiments quantitatively.

  10. Genetic aspects of arteriosclerosis.

    PubMed

    Goldbourt, U; Neufeld, H N

    1986-01-01

    This review discusses the genetic factors in the development of arteriosclerosis and coronary heart disease (CHD). In several studies, multivariate analysis of prospective mortality/morbidity data and angiographic findings have indicated that a family history of CHD contributed to CHD risk independently of the established risk factors. In addition, ethnic groups that differ in the prevalence and incidence of CHD also markedly differ in blood groups and protein-enzymatic markers. These or other genetic differences may affect CHD rates. Data from fraternal and identical twins, the source of some early genetic CHD findings, are reviewed. Genetic disorders of lipoprotein metabolism and transport, such as familial hypercholesterolemia, as well as other monogenic disorders are discussed. The role of apoprotein E polymorphism i other monogenic disorders are discussed. The role of apoprotein E polymorphism in determining plasma LDL variability among individuals is considered. Recombinant DNA technology, molecular cloning, and the identification of restriction fragment length polymorphisms are new tools for investigators who assess DNA polymorphism. Recent advances in that domain include: DNA polymorphisms affecting blood levels of apo A-I and A-II, association of a DNA insertion on chromosome 19 with severe premature atherosclerosis, and information concerning linkage of the genes for various apolipoproteins. In addition, the evidence for a major genetic component in diabetes mellitus and research into the genetic aspects of hypertension are reviewed. The male/female ratio in pathologically and epidemiologically assessed atherosclerosis may provide clues to the role of genetics. Early structural changes in the coronary artery intima are compatible with the ethnic and gender predilection. A key question in understanding underlying mechanisms in atherosclerosis is why coronary arteries are occluded in individuals whose other arterial systems are largely unaffected. The

  11. Power Quality Aspects in a Wind Power Plant: Preprint

    SciTech Connect

    Muljadi, E.; Butterfield, C. P.; Chacon, J.; Romanowitz, H.

    2006-01-01

    Although many operational aspects affect wind power plant operation, this paper focuses on power quality. Because a wind power plant is connected to the grid, it is very important to understand the sources of disturbances that affect the power quality.

  12. Understanding How Grammatical Aspect Influences Legal Judgment.

    PubMed

    Sherrill, Andrew M; Eerland, Anita; Zwaan, Rolf A; Magliano, Joseph P

    2015-01-01

    Recent evidence suggests that grammatical aspect can bias how individuals perceive criminal intentionality during discourse comprehension. Given that criminal intentionality is a common criterion for legal definitions (e.g., first-degree murder), the present study explored whether grammatical aspect may also impact legal judgments. In a series of four experiments participants were provided with a legal definition and a description of a crime in which the grammatical aspect of provocation and murder events were manipulated. Participants were asked to make a decision (first- vs. second-degree murder) and then indicate factors that impacted their decision. Findings suggest that legal judgments can be affected by grammatical aspect but the most robust effects were limited to temporal dynamics (i.e., imperfective aspect results in more murder actions than perfective aspect), which may in turn influence other representational systems (i.e., number of murder actions positively predicts perceived intentionality). In addition, findings demonstrate that the influence of grammatical aspect on situation model construction and evaluation is dependent upon the larger linguistic and semantic context. Together, the results suggest grammatical aspect has indirect influences on legal judgments to the extent that variability in aspect changes the features of the situation model that align with criteria for making legal judgments. PMID:26496364

  13. Understanding How Grammatical Aspect Influences Legal Judgment.

    PubMed

    Sherrill, Andrew M; Eerland, Anita; Zwaan, Rolf A; Magliano, Joseph P

    2015-01-01

    Recent evidence suggests that grammatical aspect can bias how individuals perceive criminal intentionality during discourse comprehension. Given that criminal intentionality is a common criterion for legal definitions (e.g., first-degree murder), the present study explored whether grammatical aspect may also impact legal judgments. In a series of four experiments participants were provided with a legal definition and a description of a crime in which the grammatical aspect of provocation and murder events were manipulated. Participants were asked to make a decision (first- vs. second-degree murder) and then indicate factors that impacted their decision. Findings suggest that legal judgments can be affected by grammatical aspect but the most robust effects were limited to temporal dynamics (i.e., imperfective aspect results in more murder actions than perfective aspect), which may in turn influence other representational systems (i.e., number of murder actions positively predicts perceived intentionality). In addition, findings demonstrate that the influence of grammatical aspect on situation model construction and evaluation is dependent upon the larger linguistic and semantic context. Together, the results suggest grammatical aspect has indirect influences on legal judgments to the extent that variability in aspect changes the features of the situation model that align with criteria for making legal judgments.

  14. Low-aspect-ratio optimization studies for ATF-II

    SciTech Connect

    Hirshman, S.P.; Morris, R.N.; Hedrick, C.L.; Lyon, J.F.; Rome, J.A.; Painter, S.L.; Van Rij, W.I.

    1989-01-01

    A numerical procedure for optimizing stellarator MHD and transport properties at finite ..beta.. is described. This method is applied to finding a low-aspect-ratio ATF-II configuration. 4 refs., 6 figs.

  15. Affect and Self-Regulation

    ERIC Educational Resources Information Center

    Malmivuori, Marja-Liisa

    2006-01-01

    This paper presents affect as an essential aspect of students' self-reflection and self-regulation. The introduced concepts of self-system and self-system process stress the importance of self-appraisals of personal competence and agency in affective responses and self-regulation in problem solving. Students are viewed as agents who constantly…

  16. Aspects of Language

    ERIC Educational Resources Information Center

    Ullmann, Stephen

    1974-01-01

    Several aspects of language--code, relation of structure to meaning, creativity, capacity to influence thought--are discussed, as well as reasons for including foreign language study in school and university. (RM)

  17. Environmental colour affects aspects of single-species population dynamics.

    PubMed

    Petchey, O L

    2000-04-22

    Single-species populations of ciliates (Colpidium and Paramecium) experienced constant temperature or white or reddened temperature fluctuations in aquatic microcosms in order to test three hypotheses about how environmental colour influences population dynamics. (i) Models predict that the colour of population dynamics is tinged by the colour of the environmental variability. However, environmental colour had no effect on the colour of population dynamics. All population dynamics in this experiment were reddened, regardless of environmental colour. (ii) Models predict that populations will track reddened environmental variability more closely than white environmental variability and that populations with a higher intrinsic growth rate (r) will track environmental variability more closely than populations with a low r. The experimental populations behaved as predicted. (iii) Models predict that population variability is determined by interaction between r and the environmental variability. The experimental populations behaved as predicted. These results show that (i) reddened population dynamics may need no special explanation, such as reddened environments, spatial subdivision or interspecific interactions, and (ii) and (iii) that population dynamics are sensitive to environmental colour, in agreement with population models. Correct specification of the colour of the environmental variability in models is required for accurate predictions. Further work is needed to study the effects of environmental colour on communities and ecosystems.

  18. Numerical ability predicts mortgage default.

    PubMed

    Gerardi, Kristopher; Goette, Lorenz; Meier, Stephan

    2013-07-01

    Unprecedented levels of US subprime mortgage defaults precipitated a severe global financial crisis in late 2008, plunging much of the industrialized world into a deep recession. However, the fundamental reasons for why US mortgages defaulted at such spectacular rates remain largely unknown. This paper presents empirical evidence showing that the ability to perform basic mathematical calculations is negatively associated with the propensity to default on one's mortgage. We measure several aspects of financial literacy and cognitive ability in a survey of subprime mortgage borrowers who took out loans in 2006 and 2007, and match them to objective, detailed administrative data on mortgage characteristics and payment histories. The relationship between numerical ability and mortgage default is robust to controlling for a broad set of sociodemographic variables, and is not driven by other aspects of cognitive ability. We find no support for the hypothesis that numerical ability impacts mortgage outcomes through the choice of the mortgage contract. Rather, our results suggest that individuals with limited numerical ability default on their mortgage due to behavior unrelated to the initial choice of their mortgage.

  19. Numerical ability predicts mortgage default.

    PubMed

    Gerardi, Kristopher; Goette, Lorenz; Meier, Stephan

    2013-07-01

    Unprecedented levels of US subprime mortgage defaults precipitated a severe global financial crisis in late 2008, plunging much of the industrialized world into a deep recession. However, the fundamental reasons for why US mortgages defaulted at such spectacular rates remain largely unknown. This paper presents empirical evidence showing that the ability to perform basic mathematical calculations is negatively associated with the propensity to default on one's mortgage. We measure several aspects of financial literacy and cognitive ability in a survey of subprime mortgage borrowers who took out loans in 2006 and 2007, and match them to objective, detailed administrative data on mortgage characteristics and payment histories. The relationship between numerical ability and mortgage default is robust to controlling for a broad set of sociodemographic variables, and is not driven by other aspects of cognitive ability. We find no support for the hypothesis that numerical ability impacts mortgage outcomes through the choice of the mortgage contract. Rather, our results suggest that individuals with limited numerical ability default on their mortgage due to behavior unrelated to the initial choice of their mortgage. PMID:23798401

  20. Numerical ability predicts mortgage default

    PubMed Central

    Gerardi, Kristopher; Goette, Lorenz; Meier, Stephan

    2013-01-01

    Unprecedented levels of US subprime mortgage defaults precipitated a severe global financial crisis in late 2008, plunging much of the industrialized world into a deep recession. However, the fundamental reasons for why US mortgages defaulted at such spectacular rates remain largely unknown. This paper presents empirical evidence showing that the ability to perform basic mathematical calculations is negatively associated with the propensity to default on one’s mortgage. We measure several aspects of financial literacy and cognitive ability in a survey of subprime mortgage borrowers who took out loans in 2006 and 2007, and match them to objective, detailed administrative data on mortgage characteristics and payment histories. The relationship between numerical ability and mortgage default is robust to controlling for a broad set of sociodemographic variables, and is not driven by other aspects of cognitive ability. We find no support for the hypothesis that numerical ability impacts mortgage outcomes through the choice of the mortgage contract. Rather, our results suggest that individuals with limited numerical ability default on their mortgage due to behavior unrelated to the initial choice of their mortgage. PMID:23798401

  1. Cognitive aspects of color

    NASA Astrophysics Data System (ADS)

    Derefeldt, Gunilla A. M.; Menu, Jean-Pierre; Swartling, Tiina

    1995-04-01

    This report surveys cognitive aspects of color in terms of behavioral, neuropsychological, and neurophysiological data. Color is usually defined as psychophysical color or as perceived color. Behavioral data on categorical color perception, absolute judgement of colors, color coding, visual search, and visual awareness refer to the more cognitive aspects of color. These are of major importance in visual synthesis and spatial organization, as already shown by the Gestalt psychologists. Neuropsychological and neurophysiological findings provide evidence for an interrelation between cognitive color and spatial organization. Color also enhances planning strategies, as has been shown by studies on color and eye movements. Memory colors and the color- language connections in the brain also belong among the cognitive aspects of color.

  2. Superovulation in cattle: practical aspects of gonadotropin treatment and insemination.

    PubMed

    Kanitz, Wilhelm; Becker, Frank; Schneider, Falk; Kanitz, Ellen; Leiding, Claus; Nohner, Hans-Peter; Pöhland, Ralf

    2002-01-01

    Embryo transfer (ET) in cattle has been used for the realisation of breeding programmes world-wide for more than 20 years. The efficiency of breeding technology, i.e. the breeding progress and costs, depends to a large extent on the results of superovulatory treatment and artificial insemination (A.I.). The results of this step are characterised by a high degree of variation. Numerous attempts have been undertaken to explain the reason(s) for this. Numerous attempts have also been made to clarify the importance of different factors affecting the results. Undoubtedly, the applied hormones and the scheme of insemination itself are main factors, which influence the number and the portion of transferable embryos. Therefore this paper is focused on the following aspects of superovulatory treatment with FSH: dose-response relations, bioactivity of the glycoprotein, FSH/LH ratio, ovulation time and time-oriented insemination, frequency of gonadotropin administration and follicular population at the time of gonadotropin application. PMID:12625423

  3. Medical Aspects of Surfing.

    ERIC Educational Resources Information Center

    Renneker, Mark

    1987-01-01

    The medical aspects of surfing include ear and eye injuries and sprains and strains of the lower back and neck, as well as skin cancer from exposure to the sun. Treatment, rehabilitation, and prevention of these problems are discussed. Surfing is recommended as part of an exercise program for reasonably healthy people. (Author/MT)

  4. Global aspects of monsoons

    NASA Technical Reports Server (NTRS)

    Murakami, T.

    1985-01-01

    Recent developments are studied in three areas of monsoon research: (1) global aspects of the monsoon onset, (2) the orographic influence of the Tibetan Plateau on the summer monsoon circulations, and (3) tropical 40 to 50 day oscillations. Reference was made only to those studies that are primarily based on FGGE Level IIIb data. A brief summary is given.

  5. Sociological Aspects of Deafness.

    ERIC Educational Resources Information Center

    World Federation of the Deaf, Rome (Italy).

    Nine conference papers treat the sociological aspects of deafness. Included are "Individuals Being Deaf and Blind and Living with a Well Hearing Society" by A. Marx (German Federal Republic), "A Deaf Man's Experiences in a Hearing World" by A. B. Simon(U.S.A.), "Problem of Text Books and School Appliances for Vocational Education of Deaf Adults"…

  6. Aspects of Marine Ecology.

    ERIC Educational Resources Information Center

    Awkerman, Gary L.

    This publication is designed for use in standard science curricula to develop oceanologic manifestations of certain science topics. Included are teacher guides, student activities, and demonstrations to impart ocean science understanding, specifically, aspects of marine ecology, to high school students. The course objectives include the ability of…

  7. Numerical study of forced convective heat transfer around airships

    NASA Astrophysics Data System (ADS)

    Dai, Qiumin; Fang, Xiande

    2016-02-01

    Forced convective heat transfer is an important factor that affects the thermal characteristics of airships. In this paper, the steady state forced convective heat transfer around an ellipsoid is numerically investigated. The numerical simulation is carried out by commercial computational fluid dynamic (CFD) software over the extended Re range from 20 to 108 and the aspect ratio from 2 to 4. Based on the regression and optimization with software, a new piecewise correlation of the Nusselt number at constant wall temperature for ellipsoid is proposed, which is suitable for applications to airships and other ellipse shaped bodies such as elliptical balloons. The thermal characteristics of a stratospheric airship in midsummer located in the north hemisphere are numerical studied. The helium temperature predicated using the new correlation is compared to those predicted by correlations applicable for spheres and flat plates. The results show that the helium temperature obtained using the new correlation at noon is about 5.4 K lower than that using the correlation of spheres and about 2.1 K higher than that of flat plates.

  8. Numerical investigation of the cylinder movement in granular matter.

    PubMed

    Zhang, Xue; Sheng, Daichao; Kouretzis, George P; Krabbenhoft, Kristian; Sloan, Scott W

    2015-02-01

    We investigate numerically the mechanisms governing horizontal dragging of a rigid cylinder buried inside granular matter, with particular emphasis on enumerating drag and lift forces that resist cylinder movement. The recently proposed particle finite element method is employed, which combines the robustness of classical continuum mechanics formulations in terms of representing complex aspects of the material constitutive behavior, with the effectiveness of discrete element methods in simulating ultralarge deformation problems. The investigation focuses on the effect of embedment depth, cylinder roughness, granular matter macromechanical properties, and of the magnitude of the cylinder's horizontal displacement on the amplitude of the resisting forces, which are discussed in light of published experimental data. Interpretation of the results provides insight on how the material flow around the cylinder affects the developing resistance, and a mechanism is proposed to describe the development of a steady-state drag force at large horizontal movements of the cylinder. PMID:25768495

  9. Behavioural aspects of terrorism.

    PubMed

    Leistedt, Samuel J

    2013-05-10

    Behavioural and social sciences are useful in collecting and analysing intelligence data, understanding terrorism, and developing strategies to combat terrorism. This article aims to examine the psychopathological concepts of terrorism and discusses the developing roles for behavioural scientists. A systematic review was conducted of studies investigating behavioural aspects of terrorism. These studies were identified by a systematic search of databases, textbooks, and a supplementary manual search of references. Several fundamental concepts were identified that continue to influence the motives and the majority of the behaviours of those who support or engage in this kind of specific violence. Regardless of the psychological aspects and new roles for psychiatrists, the behavioural sciences will continue to be called upon to assist in developing better methods to gather and analyse intelligence, to understand terrorism, and perhaps to stem the radicalisation process.

  10. Psychosocial Aspects of Obesity.

    PubMed

    Beck, Amy R

    2016-01-01

    This article is the sixth in a series of the comorbidities of childhood obesity and reviews psychosocial aspects with a focus on weight-based victimization and discrimination stemming from weight bias and stigma. Outcomes from these bullying and discriminatory experiences are pervasive and impact youth across all settings, including school. Lastly, this article provides recommendations on how to reduce bias and stigma to better serve these students in the school environment. PMID:26739931

  11. Aspects of B physics

    SciTech Connect

    Gaillard, M.K.

    1987-10-14

    Various aspects of weak decays are commented on. Probing of the standard model and of phenomena beyond the standard model are discussed, followed by a theoretical view of B mesons and some experimental observations on B mesons. The point is made that any data on B decay would be interesting in that it would provide powerful new constraints in analyses of the standard model and extensions thereof. (LEW)

  12. Numerical simulation of small perturbation transonic flows

    NASA Technical Reports Server (NTRS)

    Seebass, A. R.; Yu, N. J.

    1976-01-01

    The results of a systematic study of small perturbation transonic flows are presented. Both the flow over thin airfoils and the flow over wedges were investigated. Various numerical schemes were employed in the study. The prime goal of the research was to determine the efficiency of various numerical procedures by accurately evaluating the wave drag, both by computing the pressure integral around the body and by integrating the momentum loss across the shock. Numerical errors involved in the computations that affect the accuracy of drag evaluations were analyzed. The factors that effect numerical stability and the rate of convergence of the iterative schemes were also systematically studied.

  13. Numerical errors in the presence of steep topography: analysis and alternatives

    SciTech Connect

    Lundquist, K A; Chow, F K; Lundquist, J K

    2010-04-15

    It is well known in computational fluid dynamics that grid quality affects the accuracy of numerical solutions. When assessing grid quality, properties such as aspect ratio, orthogonality of coordinate surfaces, and cell volume are considered. Mesoscale atmospheric models generally use terrain-following coordinates with large aspect ratios near the surface. As high resolution numerical simulations are increasingly used to study topographically forced flows, a high degree of non-orthogonality is introduced, especially in the vicinity of steep terrain slopes. Numerical errors associated with the use of terrainfollowing coordinates can adversely effect the accuracy of the solution in steep terrain. Inaccuracies from the coordinate transformation are present in each spatially discretized term of the Navier-Stokes equations, as well as in the conservation equations for scalars. In particular, errors in the computation of horizontal pressure gradients, diffusion, and horizontal advection terms have been noted in the presence of sloping coordinate surfaces and steep topography. In this work we study the effects of these spatial discretization errors on the flow solution for three canonical cases: scalar advection over a mountain, an atmosphere at rest over a hill, and forced advection over a hill. This study is completed using the Weather Research and Forecasting (WRF) model. Simulations with terrain-following coordinates are compared to those using a flat coordinate, where terrain is represented with the immersed boundary method. The immersed boundary method is used as a tool which allows us to eliminate the terrain-following coordinate transformation, and quantify numerical errors through a direct comparison of the two solutions. Additionally, the effects of related issues such as the steepness of terrain slope and grid aspect ratio are studied in an effort to gain an understanding of numerical domains where terrain-following coordinates can successfully be used and

  14. Affective Learning.

    ERIC Educational Resources Information Center

    Brown, Charles T.

    This paper addresses itself to the question, "What does feeling have to do with knowing?" Two movements in affective education are discussed which have come into focus in recent years and which attempt to define the relationship between knowing and feeling. The first, a conscious application of the role of arousal in learning, emphasizes arousal…

  15. Numerical Boundary Condition Procedures

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Topics include numerical procedures for treating inflow and outflow boundaries, steady and unsteady discontinuous surfaces, far field boundaries, and multiblock grids. In addition, the effects of numerical boundary approximations on stability, accuracy, and convergence rate of the numerical solution are discussed.

  16. Global Aspects of Radiation Memory

    NASA Astrophysics Data System (ADS)

    Winicour, Jeffrey

    2015-04-01

    The gravitational radiation memory effect produces a net displacement of test particles. The proposed sources lead to E mode memory, as characterized by an even parity polarization pattern. Although odd parity, or B mode, radiation memory is mathematically possible, no physically realistic source has been identified. There is an electromagnetic counterpart to radiation memory which produces a net momentum ``kick'' of charged test particles. A global null cone treatment shows that electromagnetic E mode memory requires unbounded charges and no physically realistic source produces B mode memory. A compelling theoretical aspect of E mode gravitational radiation memory is related to the supertranslations in the Bondi-Metzner-Sachs (BMS) asymptotic symmetry group. For a stationary system, supertranslations can be eliminated and the BMS group reduced to the Poincare group, for which angular momentum is well-defined. However, for a stationary to stationary transition, the two Poincare groups obtained at early and late times differ by a supertranslation if the gravitational radiation has nonzero E mode memory. This suggests a distinctly general relativistic mechanism for angular momentum loss and presents a ripe problem for the numerical simulation of high spin black hole binaries. Supported by NSF grant PHY-1201276 to the University of Pittsburgh.

  17. Affect, Behavioural Schemas and the Proving Process

    ERIC Educational Resources Information Center

    Selden, Annie; McKee, Kerry; Selden, John

    2010-01-01

    In this largely theoretical article, we discuss the relation between a kind of affect, behavioural schemas and aspects of the proving process. We begin with affect as described in the mathematics education literature, but soon narrow our focus to a particular kind of affect--nonemotional cognitive feelings. We then mention the position of feelings…

  18. Ceramics with decorative aspect

    NASA Astrophysics Data System (ADS)

    Voica, Cezara

    2009-08-01

    The last decades brought the development of bone china techniques used for producing the decorative articles. These products can be glazed with a transparent and thin glaze layer, even with more special (decorative) ones which gives new aesthetic aspect. The present article presents the results obtained after the studies performed for matte glazes for decorative bone china. As microcrystalization agent were used zinc oxide; the content of this oxide bring some changes of the basic glaze thus the chemical composition must be adjusted as the fluxes would present the desired properties after the heating process.

  19. Theoretical aspects of immunity.

    PubMed

    Deem, Michael W; Hejazi, Pooya

    2010-01-01

    The immune system recognizes a myriad of invading pathogens and their toxic products. It does so with a finite repertoire of antibodies and T cell receptors. We here describe theories that quantify the dynamics of the immune system. We describe how the immune system recognizes antigens by searching the large space of receptor molecules. We consider in some detail the theories that quantify the immune response to influenza and dengue fever. We review theoretical descriptions of the complementary evolution of pathogens that occurs in response to immune system pressure. Methods including bioinformatics, molecular simulation, random energy models, and quantum field theory contribute to a theoretical understanding of aspects of immunity.

  20. [The physiotherapic aspect of omeral epicondilitis (author's transl)].

    PubMed

    Marenghi, P; Tella, G C

    1976-01-01

    The Authors describe history, etiopatogenesis, clinic, therapy of omeral epicondilitis, very frequent affection. Physiotherapic aspects are studied by different methods. The indications are different compared to clinical aspect, pain modality, relapse eventuality. They conclude with personal considerations based on what observed in Orthopedic Clinica of Parma University.

  1. 25 CFR 87.9 - Programming aspects of plans.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Programming aspects of plans. 87.9 Section 87.9 Indians... JUDGMENT FUNDS § 87.9 Programming aspects of plans. In assessing any tribal programming proposal the... such reservation residents; the nature of recent programming affecting the subject tribe or group...

  2. 25 CFR 87.9 - Programming aspects of plans.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Programming aspects of plans. 87.9 Section 87.9 Indians... JUDGMENT FUNDS § 87.9 Programming aspects of plans. In assessing any tribal programming proposal the... such reservation residents; the nature of recent programming affecting the subject tribe or group...

  3. 25 CFR 87.9 - Programming aspects of plans.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Programming aspects of plans. 87.9 Section 87.9 Indians... JUDGMENT FUNDS § 87.9 Programming aspects of plans. In assessing any tribal programming proposal the... such reservation residents; the nature of recent programming affecting the subject tribe or group...

  4. 25 CFR 87.9 - Programming aspects of plans.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Programming aspects of plans. 87.9 Section 87.9 Indians... JUDGMENT FUNDS § 87.9 Programming aspects of plans. In assessing any tribal programming proposal the... such reservation residents; the nature of recent programming affecting the subject tribe or group...

  5. 25 CFR 87.9 - Programming aspects of plans.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Programming aspects of plans. 87.9 Section 87.9 Indians... JUDGMENT FUNDS § 87.9 Programming aspects of plans. In assessing any tribal programming proposal the... such reservation residents; the nature of recent programming affecting the subject tribe or group...

  6. Diabetic patients: Psychological aspects.

    PubMed

    Adili, Fatemeh; Larijani, Bagher; Haghighatpanah, Mohammadreza

    2006-11-01

    This study was undertaken to consider the psychological aspect of diabetes with regard to improving clinical outcomes. The review was limited to literature reports on the causes, solutions, and treatments of some common psychological problems known to complicate diabetes management. A literature search was undertaken using Pub-Med, CINAHL, Proquest, Elsevier, Blackwell Synergy, Ovid, Ebsco, Rose net, and Google websites, including studies published in English journals between 1995 and 2006. Therefore about 88 articles were selected based on the inclusion criteria. In earlier studies, relatively little empirical research was found to substantiate the effect of psychological counseling in complicated diabetes. The greatest deficits were seen in areas of mental health, self-esteem parent impact, and family cohesion. There were some different factors, which influence the psychological aspect of diabetic patients, such as age, gender, place of living, familial and social support, motivation, energy, life satisfaction, and lifestyle. There are various types of solutions for coping with the psychological problems in diabetic clients. The most essential solution lies in educating the patients and healthcare providers on the subject. Before initiating each educational intervention, a thorough assessment would be crucial. Treatment plans may benefit from cognitive behavior therapy (CBT), behavior family therapy, improving family communication, problem-solving skills, and providing motivation for diabetic patients. Moreover, it seems that the close collaboration between diabetologists and psychologists would be fruitful.

  7. Regulatory aspects on nanomedicines.

    PubMed

    Sainz, Vanessa; Conniot, João; Matos, Ana I; Peres, Carina; Zupancic, Eva; Moura, Liane; Silva, Liana C; Florindo, Helena F; Gaspar, Rogério S

    2015-12-18

    Nanomedicines have been in the forefront of pharmaceutical research in the last decades, creating new challenges for research community, industry, and regulators. There is a strong demand for the fast development of scientific and technological tools to address unmet medical needs, thus improving human health care and life quality. Tremendous advances in the biomaterials and nanotechnology fields have prompted their use as promising tools to overcome important drawbacks, mostly associated to the non-specific effects of conventional therapeutic approaches. However, the wide range of application of nanomedicines demands a profound knowledge and characterization of these complex products. Their properties need to be extensively understood to avoid unpredicted effects on patients, such as potential immune reactivity. Research policy and alliances have been bringing together scientists, regulators, industry, and, more frequently in recent years, patient representatives and patient advocacy institutions. In order to successfully enhance the development of new technologies, improved strategies for research-based corporate organizations, more integrated research tools dealing with appropriate translational requirements aiming at clinical development, and proactive regulatory policies are essential in the near future. This review focuses on the most important aspects currently recognized as key factors for the regulation of nanomedicines, discussing the efforts under development by industry and regulatory agencies to promote their translation into the market. Regulatory Science aspects driving a faster and safer development of nanomedicines will be a central issue for the next years.

  8. Effect of aspect ratio on the energy extraction efficiency of three-dimensional flapping foils

    NASA Astrophysics Data System (ADS)

    Deng, Jian; Caulfield, C. P.; Shao, Xueming

    2014-04-01

    Numerical simulations are used to investigate the effect of variation of the aspect ratio and the structure of pitching motions on the energy extraction efficiency and wake topology of flapping foils. The central aim is to predict the energy extraction performance and efficiency of a flapping-foil-based energy harvesting system (EHS) in realistic working conditions with finite aspect ratios. A sinusoidal heaving motion is imposed upon the foil, as well as both a sinusoidal pitching motion and a variety of trapezoidal-like periodic pitching motions. The simulations employ a finite-volume method with body-fitted moving grids, allowing the capture of flow structure near the foil surface. A detailed analysis of the hydrodynamic performance shows two peaks per periodic cycle in the lift force time histories or equivalently, the energy extraction time histories. The first primary peak corresponds to an effective angle of attack around 15.4°, indicating good attachment of the flow on the foil surface without significant flow separation. The secondary peak corresponds to a leading edge vortex (LEV) travelling on the foil surface. The shape of the LEV is altered markedly as the aspect ratio varies, and consequently the secondary peak in the lift force time history is strongly affected by the effects of three-dimensionality for foils with smaller aspect ratios. By examining the relationship between energy extraction efficiency and aspect ratio, a critical aspect ratio of AR = 4 is identified for sinusoidal pitching motions, below which the three-dimensional low-aspect-ratio characteristics dominate the flow evolution. Therefore, the compromise between higher energy extraction efficiency and lower costs of manufacturing and installation suggests that an aspect ratio around AR = 4 is the most appropriate choice for a real EHS. Furthermore, although trapezoidal-like pitching motions are known to improve the efficiency in flows restricted to two dimensions, particularly for non

  9. Research on numerical algorithms for large space structures

    NASA Technical Reports Server (NTRS)

    Denman, E. D.

    1982-01-01

    Numerical algorithms for large space structures were investigated with particular emphasis on decoupling method for analysis and design. Numerous aspects of the analysis of large systems ranging from the algebraic theory to lambda matrices to identification algorithms were considered. A general treatment of the algebraic theory of lambda matrices is presented and the theory is applied to second order lambda matrices.

  10. Psychological aspects of von Recklinghausen neurofibromatosis (NF1)

    PubMed Central

    Mouridsen, S E; Sørensen, S A

    1995-01-01

    Neurofibromatosis is a devasting autosomal dominant disease which is extremely variable in its symptomatology, intensity, and progression. There have been numerous reports published about the physical aspects of neurofibromatosis, while psychological issues have been given little attention so far. The present article presents a review of the current knowledge concerning psychological aspects of neurofibromatosis. Information is provided relating to physical appearance, intellectual impairment, neuropsychological findings, learning disability, and psychiatric disorders. PMID:8825915

  11. Current aspects of occupational chemical carcinogenesis

    NASA Technical Reports Server (NTRS)

    Lassiter, D.

    1975-01-01

    The history of measures to control occupational exposure to carcinogenic substances is reviewed. Health hazards associated with exposure to a certain chemical substance must be considered not only from the aspects of its acute or chronic toxicity, but also from its potential to produce tumors (latent effect). There can be no clear distinction between classic toxicity and oncogenesis until the mechanisms of both are completely understood for a given chemical substance. The assessment of carcinogenic potential for a specific substance must include the consideration of published information, monitoring and control data from the affected industry, and the in-depth epidemiologic experience of affected employees.

  12. Aspects of Plant Intelligence

    PubMed Central

    TREWAVAS, ANTHONY

    2003-01-01

    Intelligence is not a term commonly used when plants are discussed. However, I believe that this is an omission based not on a true assessment of the ability of plants to compute complex aspects of their environment, but solely a reflection of a sessile lifestyle. This article, which is admittedly controversial, attempts to raise many issues that surround this area. To commence use of the term intelligence with regard to plant behaviour will lead to a better understanding of the complexity of plant signal transduction and the discrimination and sensitivity with which plants construct images of their environment, and raises critical questions concerning how plants compute responses at the whole‐plant level. Approaches to investigating learning and memory in plants will also be considered. PMID:12740212

  13. Aspects, Wrappers and Events

    NASA Technical Reports Server (NTRS)

    Filman, Robert E.

    2003-01-01

    This viewgraph presentation provides information on Object Infrastructure Framework (OIF), an Aspect-Oriented Programming (AOP) system. The presentation begins with an introduction to the difficulties and requirements of distributed computing, including functional and non-functional requirements (ilities). The architecture of Distributed Object Technology includes stubs, proxies for implementation objects, and skeletons, proxies for client applications. The key OIF ideas (injecting behavior, annotated communications, thread contexts, and pragma) are discussed. OIF is an AOP mechanism; AOP is centered on: 1) Separate expression of crosscutting concerns; 2) Mechanisms to weave the separate expressions into a unified system. AOP is software engineering technology for separately expressing systematic properties while nevertheless producing running systems that embody these properties.

  14. On virial analysis at low aspect ratio

    DOE PAGES

    Bongard, Michael W.; Barr, Jayson L.; Fonck, Raymond J.; Reusch, Joshua A.; Thome, Kathreen E.

    2016-07-28

    The validity of virial analysis to infer global MHD equilibrium poloidal beta βp and internal inductance ℓi from external magnetics measurements is examined for low aspect ratio configurations with A < 2. Numerical equilibrium studies at varied aspect ratio are utilized to validate the technique at finite aspect ratio. The effect of applying high-A approximations to low-A experimental data is quantified and demonstrates significant over-estimation of stored energy (factors of 2–10) in spherical tokamak geometry. Experimental approximations to equilibrium-dependent volume integral terms in the analysis are evaluated at low-A. Highly paramagnetic configurations are found to be inadequately represented through themore » virial mean radius parameter RT. Alternate formulations for inferring βp and ℓi that are independent of RT to avoid this difficulty are presented for the static isotropic limit. Lastly, these formulations are suitable for fast estimation of tokamak stored energy components at low aspect ratio using virial analysis.« less

  15. Environmental aspects of wastewater reclamation.

    PubMed

    Sharma, Sunil; Choudhary, Mahendra Pratap

    2007-07-01

    The population is increasing rapidly and the demand for water by cities, industries and agriculture has tended to grow even faster than the population. Wastewater reclamation consists of a combination of conventional and advanced treatment processes employed to return a wastewater to nearly original quality, reclaiming the water. The environmental health aspects associated with reclamation of wastewater include quality aspects and public health aspects. An attempt has been made in the present paper to describe these aspects and to suggest appropriate solutions.

  16. [Affective dependency].

    PubMed

    Scantamburlo, G; Pitchot, W; Ansseau, M

    2013-01-01

    Affective dependency is characterized by emotional distress (insecure attachment) and dependency to another person with a low self-esteem and reassurance need. The paper proposes a reflection on the definition of emotional dependency and the confusion caused by various denominations. Overprotective and authoritarian parenting, cultural and socio-environmental factors may contribute to the development of dependent personality. Psychological epigenetic factors, such as early socio-emotional trauma could on neuronal circuits in prefronto-limbic regions that are essential for emotional behaviour.We also focus on the interrelations between dependent personality, domestic violence and addictions. The objective for the clinician is to propose a restoration of self-esteem and therapeutic strategies focused on autonomy.

  17. [Affective dependency].

    PubMed

    Scantamburlo, G; Pitchot, W; Ansseau, M

    2013-01-01

    Affective dependency is characterized by emotional distress (insecure attachment) and dependency to another person with a low self-esteem and reassurance need. The paper proposes a reflection on the definition of emotional dependency and the confusion caused by various denominations. Overprotective and authoritarian parenting, cultural and socio-environmental factors may contribute to the development of dependent personality. Psychological epigenetic factors, such as early socio-emotional trauma could on neuronal circuits in prefronto-limbic regions that are essential for emotional behaviour.We also focus on the interrelations between dependent personality, domestic violence and addictions. The objective for the clinician is to propose a restoration of self-esteem and therapeutic strategies focused on autonomy. PMID:23888587

  18. Comprehensive numerical modelling of tokamaks

    SciTech Connect

    Cohen, R.H.; Cohen, B.I.; Dubois, P.F.

    1991-01-03

    We outline a plan for the development of a comprehensive numerical model of tokamaks. The model would consist of a suite of independent, communicating packages describing the various aspects of tokamak performance (core and edge transport coefficients and profiles, heating, fueling, magnetic configuration, etc.) as well as extensive diagnostics. These codes, which may run on different computers, would be flexibly linked by a user-friendly shell which would allow run-time specification of packages and generation of pre- and post-processing functions, including workstation-based visualization of output. One package in particular, the calculation of core transport coefficients via gyrokinetic particle simulation, will become practical on the scale required for comprehensive modelling only with the advent of teraFLOP computers. Incremental effort at LLNL would be focused on gyrokinetic simulation and development of the shell.

  19. Numerical orbit generators of artificial earth satellites

    NASA Astrophysics Data System (ADS)

    Kugar, H. K.; Dasilva, W. C. C.

    1984-04-01

    A numerical orbit integrator containing updatings and improvements relative to the previous ones that are being utilized by the Departmento de Mecanica Espacial e Controle (DMC), of INPE, besides incorporating newer modellings resulting from the skill acquired along the time is presented. Flexibility and modularity were taken into account in order to allow future extensions and modifications. Characteristics of numerical accuracy, processing quickness, memory saving as well as utilization aspects were also considered. User's handbook, whole program listing and qualitative analysis of accuracy, processing time and orbit perturbation effects were included as well.

  20. Emerging therapeutic aspects in oncology

    PubMed Central

    MacEwan, David J

    2013-01-01

    Cancer remains a peculiarly stubborn disease to treat. Some forms of cancer have seen tremendous advances in the effectiveness of their treatments, whereas other forms have remained resistant to pharmacological control. This lack of hope for success is in part due to the types of drugs that are used in the clinic, and the targeted biological system being based purely on cellular growth rates. However, recent drugs designed to affect specific signalling pathways or proteins have been showing much success. Thanks to the ingenuity of pharmacologists in understanding and targeting these processes, there have been real improvements in treatment. Here we are presented with some of the research into such critical systems that have to be understood, so that they can be conquered. We will also look at the challenges facing cancer pharmacologists and what the field may present to us all in the future. Linked Articles This article is part of a themed section on Emerging Therapeutic Aspects in Oncology. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.169.issue-8 PMID:23889318

  1. [Legal aspects of ritual circumcision].

    PubMed

    Schreiber, M; Schott, G E; Rascher, W; Bender, A W

    2009-12-01

    Female circumcision (genital mutilation) is a criminal violation of human rights under German law. Even with consent of the person to be circumcised and/or her legal representative this procedure must not be carried out since a consent to female circumcision is unethical and therefore void. As much consent as there is on female circumcision the legal situation with ritual male circumcision is very unclear. In practice and unnoticed by the public male circumcision is carried out - be it for medical or ritual reasons - without deeper-going reflexions on the clearness of the medical indication or the legal situation with ritual circumcision. From the medical aspect there are big differences between female and male circumcision but also certain parallels. Various reasons, partly founded in prejudice and misinformation, make people refrain from regarding circumcision of boys also as illegal. Contrary to the prevailing opinion male circumcision also represents a bodily harm which a doctor can only carry out after a preoperative interview and with the consent of the affected person. Since ritual male circumcision does not serve the wellbeing of a child it is not possible for the parents to give their consent to the circumcision in lieu of the child. Male circumcision is only permitted if the child has given his consent and is thus only legally permitted if the child has reached an age at which he is mature enough to understand the meaning and extent of such an action which is hardly the case before he has completed his 16 (th) year.

  2. Applied aspects of chronoergohygiene.

    PubMed

    Gaffuri, E; Costa, G

    1986-01-01

    Chronoergohygiene defines a field of study set on optimizing the work timing compared to the desiderata of human physiology in order to improve the working conditions. Production systems follow their own laws with a timing resulting from economic, technological and natural factors; this timing could contrast with che chronological variables of the person 'involved'. Important aspects to be considered in this regard concern: a energy expense and nutrition, in relation to the mechanization and automation of the working tasks, sociocultural models, individual behaviors in eating habits; b. work performance, with particular reference to the modifications during the life-span and the rhythmic variations in the circadian period; c. toxicologic risks, considering problems of chronokinetics of the toxic agent and of 'chronoesthesia' of the body functions and apparatuses; d. work and social organization, with special reference to shift work, work pace and commuting. The research for a dynamic evaluation of the human-machine interaction in time and into forms of chronological compatibility between man and work organization should optimize industrial hygiene.

  3. Strategic Aspects of Communication

    NASA Astrophysics Data System (ADS)

    Hagen, Edward; Hammerstein, Peter; Hess, Nicole

    Rarely do human behavioral scientists and scholars study language, music, and other forms of communication as strategies—a means to some end. Some even deny that communication is the primary function of these phenomena. Here we draw upon selections of our earlier work to briefly define the strategy concept and sketch how decision theory, developed to explain the behavior of rational actors, is applied to evolved agents. Communication can then be interpreted as a strategy that advances the "fitness interests" of such agents. When this perspective is applied to agents with conflicts of interest, deception emerges as an important aspect of communication. We briefly review costly signaling, one solution to the problem of honest communication among agents with conflicts of interest. We also explore the subversion of cooperative signals by parasites and by plants defending themselves against herbivores, and we touch on biases in human gossip. Experiments with artificial embodied and communicating agents confirm that when there are conflicts of interest among agents, deception readily evolves. Finally, we consider signaling among super-organisms and the possible implications for understanding human music and language.

  4. Psychosocial aspects of abortion

    PubMed Central

    Illsley, Raymond; Hall, Marion H.

    1976-01-01

    The literature on psychosocial aspects of abortion is confusing. Individual publications must be interpreted in the context of cultural, religious, and legal constraints obtaining in a particular society at a given time, with due attention to the status and availability of alternatives to abortion that might be chosen by a woman with an “unwanted” pregnancy. A review of the literature shows that, where careful pre- and post-abortion assessments are made, the evidence is that psychological benefit commonly results, and serious adverse emotional sequelae are rare. The outcome of refused abortion seems less satisfactory, with regrets and distress frequently occurring. Research on the administration of abortion services suggests that counselling is often of value, that distress is frequently caused by delays in deciding upon and in carrying out abortions, and by unsympathetic attitudes of service providers. The phenomenon of repeated abortion seeking should be seen in the context of the availability and cost of contraception and sterilization. The place of sterilization with abortion requires careful study. A recommendation is made for observational descriptive research on populations of women with potentially unwanted pregnancies in different cultures, with comparisons of management systems and an evaluation of their impact on service users. PMID:1085671

  5. Electrical aspects of rainout

    SciTech Connect

    Rosenkilde, C.E.

    1981-11-23

    Rainout commonly denotes the aggregate of phenomena associated with precipitation scavenging of radioactivity from a cloud of nuclear debris that is within a natural rain cloud. (In contrast, the term, washout, is applicable when the nuclear cloud is below the rain cloud and the term, fallout, commonly denotes the direct gravitational settling of contaminated solid material from a nuclear cloud.) Nuclear debris aerosols may be scavenged within natural clouds by a variety of different physical processes which may involve diffusion, convection, impaction, nucleation, phoresis, turbulence, and/or electricity among others. Processes which involve electrical aspects are scrutinized for their susceptibility to the intimate presence of the radioactive-cloud environment. This particular choice of electrical processes is not accidental. Nearly all of the listed processes were examined earlier by Williams. His rough estimates suggested that electrical effects, and to a lesser extent turbulence, could enhance the scavenging of those submicron aerosols which reside in the size-range that bridges the minimum in the scavenging rate coefficient which is commonly called the Greenfield gap. This minimum in the scavenging-rate coefficient is created by the simultaneous reduction of scavenging via diffusion and the reduction of scavenging via inertial impaction. However, Williams omitted the specific influence of a radioactive environment. This report aims to remedy this omission.

  6. Cultural aspects of suicide.

    PubMed

    Maharajh, Hari D; Abdool, Petal S

    2005-09-01

    Undefined cultural factors cannot be dismissed and significantly contribute to the worldwide incidence of death by suicide. Culture is an all embracing term and defines the relationship of an individual to his environment. This study seeks to investigate the effect of culture on suicide both regionally and internationally. Culture-bound syndrome with suicidal behaviours specific to a particular culture or geographical region are discussed. Opinions are divided as to the status of religious martyrs. The law itself is silent on many aspects of suicidal behaviour and despite decriminalization of suicide as self-murder, the latter remains on the statutes of many developing countries. The Caribbean region is of concern due to its steady rise in mean suicide rate, especially in Trinidad and Tobago where socio-cultural factors are instrumental in influencing suicidal behaviour. These include transgenerational cultural conflicts, psycho-social problems, media exposure, unemployment, social distress, religion and family structure. The methods used are attributed to accessibility and lethality. Ingestion of poisonous substances is most popular followed by hanging. The gender differences seen with regard to suicidality can also be attributed to gender related psychopathology and psychosocial differences in help-seeking behaviour. These are influenced by the cultural environment to which the individual is exposed. Culture provides coping strategies to individuals; as civilization advances many of these coping mechanisms are lost unclothing the genetic predisposition of vulnerable groups. In the management of suicidal behaviour, a system of therapeutic re-culturation is needed with an emphasis on relevant culture- based therapies.

  7. Perinatal aspects of haemophilia.

    PubMed

    Economou, Marina; Banov, Laura; Ljung, Rolf

    2014-08-01

    Haemophilia is an X-linked recessive genetic disease of haemostasis. Women carriers may present with a bleeding tendency similar to milder forms of the disease. Haemophilic newborns present risk factors and patterns of bleeding that are challenging. Identification of carriers and genetic counselling before conception is considered optimal to help decide on available conception options and during pregnancy to help minimise bleeding risks for both carrier mother and affected baby. Preimplantation genetic diagnosis is attractive to many couples at risk of having a child with haemophilia and relevant technology is becoming more available although it has both practical and ethical limitations. Pregnancy in carriers should be managed by a multidisciplinary team in a comprehensive treatment centre. The optimal mode of delivery for carriers expecting a baby known to have or being at risk of haemophilia is an issue of great debate. The general consensus among authors is avoidance of instrumental delivery, foetal scalp electrodes and blood sampling in pregnancies at risk of carrying an affected foetus, as well as early recourse to Caesarean section as guided by obstetric indications. Intracranial haemorrhage, although infrequent, is one the most devastating types of bleeding in haemophilic newborns and can occur regardless of the mode of delivery or the severity of haemophilia. Early screening is proposed for all infants with severe or moderate haemophilia who have had traumatic delivery and/or have evidence of extracranial haemorrhage. Women with postpartum haemorrhage should have a bleeding work-up. PMID:24957104

  8. Neuropsychiatric aspects of dementia.

    PubMed

    Ford, Andrew H

    2014-10-01

    Dementia affects approximately 6.5% of people over the age of 65. Whilst cognitive impairment is central to the dementia concept, neuropsychiatric symptoms are invariably present at some stage of the illness. Neuropsychiatric symptoms result in a number of negative outcomes for the individual and their caregivers and are associated with higher rates of institutionalization and mortality. A number of factors have been associated with neuropsychiatric symptoms including neurobiological changes, dementia type, and illness severity and duration. Specific patient, caregiver and environmental factors are also important. Neuropsychiatric symptoms can be broadly divided into four clusters: psychotic symptoms, mood/affective symptoms, apathy, and agitation/aggression. Neuropsychiatric symptoms tend to persist over time although differing symptom profiles exist at various stages of the illness. Assessment should take into account the presenting symptoms together with an appreciation of the myriad of likely underlying causes for the symptoms. A structured assessment/rating tool can be helpful. Management should focus on non-pharmacological measures initially with pharmacological approaches reserved for more troubling symptoms. Pharmacological approaches should target specific symptoms although the evidence-base for pharmacological management is quite modest. Any medication trial should include an adequate appreciation of the risk-benefit profile in individual patients and discussion of these with both the individual and their caregiver.

  9. Nutritional aspects of selenium

    SciTech Connect

    Choe, M.

    1987-01-01

    The overall objective of this project was to investigate the effect of protein and/or dietary fiber supplementation on selenium absorption and metabolism. These relationships might be of importance in determining either minimum selenium nutritional requirements or levels of intake at which this mineral becomes toxic. Three studies compose the project. The first study involved the controlled feeding of fifteen young adults mice. Subjects were fed a laboratory-controlled diet with and without supplements of selenium or selenium plus guar gum. Selenium supplementation resulted in increased selenium excretion in urine and feces. Supplementation of guar gum, as a dietary fiber, tended to increase fecal selenium excretion and to decrease selenium balance and glutathione peroxidase (GSH-Px) activity regardless of dietary selenium levels. In study II, seventy two weanling mice were fed varied levels of dietary selenium and protein. Numerically, urinary selenium excretion increased and fecal selenium excretion and selenium balance decreased with increased dietary protein level within the same level of dietary selenium; however, selenium absorption rate tended to decrease with increased dietary protein level. Whole blood and brain tissue glutathione peroxidase activities were higher in animals fed moderate protein level than those fed the other two protein levels. In study III, a survey was conducted to investigate the correlation between dietary fiber or protein intake and urinary selenium excretion. There was a negative correlation between dietary fiber and urinary selenium excretion levels while dietary protein and urinary selenium excretion were positively correlated.

  10. International trade. Multinational aspects.

    PubMed

    Ozawa, Y

    2000-01-01

    Of numerous regional economic agreements, the European Union (EU), the North American Free Trade Agreement (NAFTA), South American Common Market (MERCOSUR), the Association of Southeast Asian Nations (ASEAN), the South Asian Association for Regional Cooperation (SAARC) and the Australia-New Zealand Closer Economic Relations Agreement are examples that are actively pursuing regional integration for freer trade of animals and animal products. The World Trade Organization (WTO) believes that regional and multinational integration initiatives are complements rather than alternatives in the pursuit of more open trade. In the efforts to harmonize SPS standards among multilateral trading nations, it is recommended that national requirements meet the standards developed by the OIE and the FAO/WHO Codex Alimentarius Commission as the minimum requirements rather than adopting the standards of the lowest common denominator. Regional grouping may hinder multilateral or bilateral trade between the countries of a group and those of the other groups. How to eliminate such non-tariff barriers as traditional trade custom remains to be examined. Ongoing activities of VICH (Harmonisation of Technical Requirements for Registration of Veterinary Medical Products) may pave the way for more open trade in pharmaceutical products between multilateral regional groups.

  11. Sociological aspects of rhinoplasty.

    PubMed

    Babuccu, Orhan; Latifoğlu, Osman; Atabay, Kenan; Oral, Nursen; Coşan, Behçet

    2003-01-01

    Although the psychological aspect of the rhinoplasty operation has been a subject of interest for a long time, with the exception of a few studies, sociological factors have been almost totally ignored. In this prospective study the personality characteristics and socioeconomic backgrounds of 216 rhinoplasty patients were evaluated. Between 1994 and 2000, a questionnaire and the Minnesota Multiphasic Personality Inventory (MMPI) were given preoperatively to 157 females and 59 males. The MMPI was also given to age-matched people as a control. Six months after surgery, patients were called on the telephone and asked to rate their satisfaction. According to questionnaire, a great majority of the rhinoplasty patients were young, unmarried women with high education levels. In the rhinoplasty group, one or more scales of the inventory were not in the normal ranges in 45% of the patients, whereas this proportion in the control group was 28% (p < 0.01). When MMPI results are considered, female patients of this study could be described as egocentric, childish, highly active, impulsive, competitive, reactive, perfectionistic about themselves, talkative, and emotionally superficial. Male patients could be described as rigid, stubborn, over-sensitive, suspicious, perfectionistic, pessimistic, over-reactive, and having somatizations. Tension and anxiety with feelings of inferiority were found to be characteristics of the male patients. The satisfaction rate after six months was reported as 72%. There was no significant correlation between MMPI results and demographic variables, nor satisfaction rate. In conclusion, the rhinoplasty patients in our study are young people at the very beginning of their careers. It could be that their personalities and socioeconomic backgrounds combine to make aesthetic surgery rewarding enough, both socially and personally, to encourage them to follow through.

  12. [Urogenital tuberculosis. Diagnostic aspects].

    PubMed

    Bennani, S; Hafiani, M; Debbagh, A; el Mrini, M; Benjelloun, S

    1995-01-01

    Urogenital tuberculosis still represents a major urologic problem in the northern part of Africa, and it is a serious disease because its diagnosis is usually late. Furthermore, the affection is frequently bilateral, which may cause the renal failure. 86 cases of urogenital tuberculosis have been reviewed. Our patients were young adults (average age: 34 year old). Cystitis is the most frequent sign (74%), hematuria, lumbar pain, genital signs and nephrologic signs are not rare. Urine was negative in 46 patients, and amicrobial leucocyturia was present in 24 cases. Diagnosis relies on a range of signs, especially intravenous pyelography that has an important place. Endoscopic biopsy did confirm the diagnosis of tuberculosis in 12 patients. Generally, definitive diagnosis was based on the histologic study of the operative specimen. PMID:8558041

  13. Omniclassical Diffusion in Low Aspect Ratio Tokamaks

    SciTech Connect

    H.E. Mynick; R.B. White; D.A. Gates

    2004-03-19

    Recently reported numerical results for axisymmetric devices with low aspect ratio A found radial transport enhanced over the expected neoclassical value by a factor of 2 to 3. In this paper, we provide an explanation for this enhancement. Transport theory in toroidal devices usually assumes large A, and that the ratio B{sub p}/B{sub t} of the poloidal to the toroidal magnetic field is small. These assumptions result in transport which, in the low collision limit, is dominated by banana orbits, giving the largest collisionless excursion of a particle from an initial flux surface. However in a small aspect ratio device one may have B{sub p}/B{sub t} {approx} 1, and the gyroradius may be larger than the banana excursion. Here, we develop an approximate analytic transport theory valid for devices with arbitrary A. For low A, we find that the enhanced transport, referred to as omniclassical, is a combination of neoclassical and properly generalized classical effects, which become dominant in the low-A, B{sub p}/B{sub t} {approx} 1 regime. Good agreement of the analytic theory with numerical simulations is obtained.

  14. Numerical predictions in acoustics

    NASA Technical Reports Server (NTRS)

    Hardin, Jay C.

    1992-01-01

    Computational Aeroacoustics (CAA) involves the calculation of the sound produced by a flow as well as the underlying flowfield itself from first principles. This paper describes the numerical challenges of CAA and recent research efforts to overcome these challenges. In addition, it includes the benefits of CAA in removing restrictions of linearity, single frequency, constant parameters, low Mach numbers, etc. found in standard acoustic analyses as well as means for evaluating the validity of these numerical approaches. Finally, numerous applications of CAA to both classical as well as modern problems of concern to the aerospace industry are presented.

  15. Numerical predictions in acoustics

    NASA Astrophysics Data System (ADS)

    Hardin, Jay C.

    Computational Aeroacoustics (CAA) involves the calculation of the sound produced by a flow as well as the underlying flowfield itself from first principles. This paper describes the numerical challenges of CAA and recent research efforts to overcome these challenges. In addition, it includes the benefits of CAA in removing restrictions of linearity, single frequency, constant parameters, low Mach numbers, etc. found in standard acoustic analyses as well as means for evaluating the validity of these numerical approaches. Finally, numerous applications of CAA to both classical as well as modern problems of concern to the aerospace industry are presented.

  16. Myocardial Na,K-ATPase: Clinical aspects

    PubMed Central

    Kjeldsen, Keld

    2003-01-01

    The specific binding of digitalis glycosides to Na,K-ATPase is used as a tool for Na,K-ATPase quantification with high accuracy and precision. In myocardial biopsies from patients with heart failure, total Na,K-ATPase concentration is decreased by around 40%; a correlation exists between a decrease in heart function and a decrease in Na,K-ATPase concentration. During digitalization, around 30% of remaining pumps are occupied by digoxin. Myocardial Na,K-ATPase is also influenced by other drugs used for the treatment of heart failure. Thus, potassium loss during diuretic therapy has been found to reduce myocardial Na,K-ATPase, whereas angiotensin-converting enzyme inhibitors may stimulate Na,K pump activity. Furthermore, hyperaldosteronism induced by heart failure has been found to decrease Na,K-ATPase activity. Accordingly, treatment with the aldosterone antagonist, spironolactone, may also influence Na,K-ATPase activity. The importance of Na,K pump modulation with heart disease, inhibition in digitalization and other effects of medication should be considered in the context of sodium, potassium and calcium regulation. It is recommended that digoxin be administered to heart failure patients who, after institution of mortality-reducing therapy, still have heart failure symptoms, and that the therapy be continued if symptoms are revealed or reduced. Digitalis glycosides are the only safe inotropic drugs for oral use that improve hemodynamics in heart failure. An important aspect of myocardial Na,K pump affection in heart disease is its influence on extracellular potassium (Ke) homeostasis. Two important aspects should be considered: potassium handling among myocytes, and effects of potassium entering the extracellular space of the heart via the bloodstream. It should be noted that both of these aspects of Ke homeostasis are affected by regulatory aspects, eg, regulation of the Na,K pump by physiological and pathophysiological conditions, as well as by medical

  17. Stability Affects of Artificial Viscosity in Detonation Modeling

    SciTech Connect

    Vitello, P; Souers, P C

    2002-06-03

    Accurate multi-dimensional modeling of detonation waves in solid HE materials is a difficult task. To treat applied problems which contain detonation waves one must consider reacting flow with a wide range of length-scales, non-linear equations of state (EOS), and material interfaces at which the detonation wave interacts with other materials. To be useful numerical models of detonation waves must be accurate, stable, and insensitive to details of the modeling such as the mesh spacing, and mesh aspect ratio for multi-dimensional simulations. Studies we have performed show that numerical simulations of detonation waves can be very sensitive to the form of the artificial viscosity term used. The artificial viscosity term is included in our ALE hydrocode to treat shock discontinuities. We show that a monotonic, second order artificial viscosity model derived from an approximate Riemann solver scheme can strongly damp unphysical oscillations in the detonation wave reaction zone, improving the detonation wave boundary wall interaction. These issues are demonstrated in 2D model simulations presented of the 'Bigplate' test. Results using LX-I 7 explosives are compared with numerical simulation results to demonstrate the affects of the artificial viscosity model.

  18. Aspects of flux compactification

    NASA Astrophysics Data System (ADS)

    Liu, Tao

    In this thesis, we study three main aspects of flux compactifications: (1) classify supergravity solutions from flux compactification; (2) construct flux-deformed geometry and 4D low-energy theory to describe these flux vacua; and (3) study 4D particle phenomenology and cosmology of flux vacua. In the first part, we review G-structure, the basic tool to study supersymmetric flux solutions, and some typical solutions obtained in heterotic, type IIA and type IIB string theories. Then we present a comprehensive classification of supersymmetric vacua of M-theory compactification on 7D manifolds with general four-form fluxes. We analyze the cases where the resulting four-dimensional vacua have N = 1, 2, 3, 4 supersymmetry and the internal space allows for SU(2)-, SU(3)- or G 2-structures. In particular, we find for N = 2 supersymmetry, that the external space-time is Minkowski and the base manifold of the internal space is conformally Kahler for SU(2) structures, while for SU(3) structures the internal space has to be Einstein-Sasaki and no internal fluxes are allowed. Moreover, we provide a new vacuum with N = 1 supersymmetry and SU(3) structure, where all fluxes are non-zero and the first order differential equations are solved. In the second part, we simply review the methods used to construct one subclass of fluxed-deformed geometry or the so-called "twisted manifold", and the associated 4D effective theory describing these flux vacua. Then by employing (generalized) Scherk-Schwarz reduction, we construct the geometric twisting for Calabi-Yau manifolds of Voisin-Borcea type (K 3 x T2)/ Z2 and study the superpotential in a type IIA orientifold based on this geometry. The twists modify the direct product by fibering the K 3 over T2 while preserving the Z2 involution. As an important application, the Voisin-Borcea class contains T6/( Z2 x Z2 ), the usual setting for intersecting D6 brane model building. Past work in this context considered only those twists inherited

  19. [Medical aspects of fasting].

    PubMed

    Gavrankapetanović, F

    1997-01-01

    Fasting (arabic-savm) was proclaimed through islam, and thus it is an obligation for Holly Prophet Muhammad s.a.v.s.-Peace be to Him-in the second year after Hijra (in 624 after Milad-born of Isa a.s.). There is a month of fasting-Ramadan-each lunar (hijra) year. So, it was 1415th fasting this year. Former Prophets have brought obligative messages on fasting to their people; so there are also certain forms of fasting with other religions i.e. with Catholics, Jews, Orthodox. These kinds of fasting above differ from muslim fasting, but they also appear obligative. All revelations have brought fasting as obligative. From medical point of view, fasting has two basical components: psychical and physical. Psychical sphere correlate closely with its fundamental ideological message. Allah dz.s. says in Quran: "... Fasting is obligative for you, as it was obligative to your precedents, as to avoid sins; during very few days (II, II, 183 & 184)." Will strength, control of passions, effort and self-discipline makes a pure faithfull person, who purify its mind and body through fasting. Thinking about The Creator is more intensive, character is more solid; and spirit and will get stronger. We will mention the hadith saying: "Essaihune humus saimun!" That means: "Travellers at the Earth are fasters (of my ummet)." The commentary of this hadith, in the Collection of 1001 hadiths (Bin bir hadis), number 485, says: "There are no travelling dervishs or monks in islam; thus there is no such a kind of relligousity in islam. In stead, it is changed by fasting and constant attending of mosque. That was proclaimed as obligation, although there were few cases of travelling in the name of relligousity, like travelling dervishs and sheichs." In this paper, the author discusses medical aspects of fasting and its positive characteristics in the respect of healthy life style and prevention of many sicks. The author mentions positive influence of fasting to certain system and organs of human

  20. Numerical simulations of plasmas

    SciTech Connect

    Dnestrovskii, Y.N.; Kostomarov, D.P.

    1986-01-01

    This book presents a modern, consistent, and systematic development of numerical computer simulation of plasmas in controlled thermonuclear fusion. The authors focus on recent Soviet research in mathematical modeling of Tokomak plasmas and present kinetic hydrodynamic and transport models.

  1. Rocket engine numerical simulator

    NASA Technical Reports Server (NTRS)

    Davidian, Ken

    1993-01-01

    The topics are presented in viewgraph form and include the following: a rocket engine numerical simulator (RENS) definition; objectives; justification; approach; potential applications; potential users; RENS work flowchart; RENS prototype; and conclusion.

  2. Rocket engine numerical simulation

    NASA Technical Reports Server (NTRS)

    Davidian, Ken

    1993-01-01

    The topics are presented in view graph form and include the following: a definition of the rocket engine numerical simulator (RENS); objectives; justification; approach; potential applications; potential users; RENS work flowchart; RENS prototype; and conclusions.

  3. Numerical Techniques in Acoustics

    NASA Technical Reports Server (NTRS)

    Baumeister, K. J. (Compiler)

    1985-01-01

    This is the compilation of abstracts of the Numerical Techniques in Acoustics Forum held at the ASME's Winter Annual Meeting. This forum was for informal presentation and information exchange of ongoing acoustic work in finite elements, finite difference, boundary elements and other numerical approaches. As part of this forum, it was intended to allow the participants time to raise questions on unresolved problems and to generate discussions on possible approaches and methods of solution.

  4. Immunological Aspects of Bagassosis

    PubMed Central

    Hearn, C. E. D.; Holford-Strevens, Valerie

    1968-01-01

    Immunological investigations of 37 patients with bagassosis, 92 unaffected bagasse workers, and 150 non-exposed controls showed that precipitins against extracts of bagasse could be demonstrated just as frequently in the unaffected and the non-exposed as in the affected. However, there was a general tendency for the precipitin levels of patients with bagassosis to fall slightly with increasing time after recovery from the clinical episode. The presence of the precipitins so far demonstrated in the sera of bagasse workers therefore appears to be of no clinical significance. Inhalation tests with an extract of bagasse, in a group of 16 patients who had had bagassosis, produced late, systemic reactions in 15 similar to those described in farmer's lung and bird fancier's lung, so supporting the hypothesis that a similar type of hypersensitivity is the cause of bagassosis. Inhalation of extracts of Thermoactinomyces vulgaris also produced typical, late reactions in 12 out of 15 subjects, whereas extracts of Micropolyspora faeni failed to produce reactions in any of 16 subjects. The specific reactions to inhalation tests with Thermoactinomyces vulgaris were typical of a precipitin-mediated type of hypersensitivity reaction and support the view that this actinomycete may be important in the aetiology of bagassosis. PMID:4972748

  5. [Arteriosclerosis--selected aspects].

    PubMed

    Kucharska, Ewa

    2014-01-01

    The article summarizes the current knowledge concerning the diagnosis of atherosclerosis and therapeutic objectives. Atherosclerosis is one of the most common medical problems. It affects adults as well as children. It leads to clinically overt cardiovascular diseases (CVD), which are the cause of premature deaths. During its course, the formation of atherosclerotic plaque takes place, along with local inflammations artery walls. Gradually growing plaque does not cause clinical symptoms until the stenosis does not exceed 70-80% of the coronary vessel diameter, causing a marked reduction in blood flow to the heart muscle. The prevention of atherosclerosis and its complications requires an individual assessment of cardiovascular risk. In people without CVD symptoms, it is recommended to use SCORE risk card for Polish population, assessing the 10-year risk of cardiac death. A key element in combating atherosclerosis is to eliminate its risk factors by both implementing pro-health policies, as well as working with individual patients. An important objective is the proper control of blood pressure. It should not exceed 140/90 mmHg. A very important role is played by correct approach to patients with moderate or unusual cardiovascular risk. Despite knowing many facts about the mechanisms of atherosclerosis and its treatment, many issues still remain to be clarified. Finding methods to influence ongoing immune processes within arteries is of particular interest, which will soon make way to new therapeutic possibilities. PMID:25338337

  6. Forensic aspects of starvation.

    PubMed

    Madea, Burkhard; Ortmann, Jan; Doberentz, Elke

    2016-09-01

    Fatal starvation is a rare cause of death in industrialized countries. However, it may have major medicolegal importance if death results from the deliberate withholding of food, especially from infants. In such cases, the task of the forensic pathologist and the medical examiner, respectively, is to clarify the cause of death and give an expert opinion on the degree and duration of starvation. Several classification systems have been developed to estimate protein-energy malnutrition in developing countries. Simpler classifications, such as the Gomez classification, use the weight expected for the respective age group as the standard. However, smaller infants will be lighter, and therefore the classification may not be accurate in this case. Following the Waterlow classification, the extent of stunted growth (referring to growth retardation in cases of chronic malnutrition) is calculated using the ratio of the measured body height to that expected for the age. Using such classification systems, grading of stunting and wasting can be achieved and may greatly help in the assessment of a given child's nutritional status in legal cases. The application of the Waterlow classification to the authors' case material and previously published cases in the literature is herein demonstrated. The Waterlow classification is not only of importance for grading the final stage of fatal starvation, but also for the chronological development of the nutritional status if anthropometrical data have been repeatedly recorded from the affected individual in vivo. PMID:27145935

  7. [Arteriosclerosis--selected aspects].

    PubMed

    Kucharska, Ewa

    2014-01-01

    The article summarizes the current knowledge concerning the diagnosis of atherosclerosis and therapeutic objectives. Atherosclerosis is one of the most common medical problems. It affects adults as well as children. It leads to clinically overt cardiovascular diseases (CVD), which are the cause of premature deaths. During its course, the formation of atherosclerotic plaque takes place, along with local inflammations artery walls. Gradually growing plaque does not cause clinical symptoms until the stenosis does not exceed 70-80% of the coronary vessel diameter, causing a marked reduction in blood flow to the heart muscle. The prevention of atherosclerosis and its complications requires an individual assessment of cardiovascular risk. In people without CVD symptoms, it is recommended to use SCORE risk card for Polish population, assessing the 10-year risk of cardiac death. A key element in combating atherosclerosis is to eliminate its risk factors by both implementing pro-health policies, as well as working with individual patients. An important objective is the proper control of blood pressure. It should not exceed 140/90 mmHg. A very important role is played by correct approach to patients with moderate or unusual cardiovascular risk. Despite knowing many facts about the mechanisms of atherosclerosis and its treatment, many issues still remain to be clarified. Finding methods to influence ongoing immune processes within arteries is of particular interest, which will soon make way to new therapeutic possibilities.

  8. Pharmacotherapeutic Aspects of Space Medicine

    NASA Technical Reports Server (NTRS)

    Putcha, Lakshmi

    2004-01-01

    produced by any drug depend upon rates of absorption, distribution, metabolism, and elimination of the drug; space flight-induced changes in blood flow and the function of the gastrointestinal (GI) tract, liver, or kidneys may alter these processes. Another important aspect of clinical efficacy of medications in space is the stability of pharmaceuticals. As the U.S. space program is moving toward extended Space Shuttle flights and beyond, to space station missions and planetary explorations, understanding how space flight affects organ systems and clinical pharmacology is necessary to optimize pharmacotherapeutics in space and ensure adequate safety and health of crewmembers.

  9. Frontiers in Numerical Relativity

    NASA Astrophysics Data System (ADS)

    Evans, Charles R.; Finn, Lee S.; Hobill, David W.

    2011-06-01

    Preface; Participants; Introduction; 1. Supercomputing and numerical relativity: a look at the past, present and future David W. Hobill and Larry L. Smarr; 2. Computational relativity in two and three dimensions Stuart L. Shapiro and Saul A. Teukolsky; 3. Slowly moving maximally charged black holes Robert C. Ferrell and Douglas M. Eardley; 4. Kepler's third law in general relativity Steven Detweiler; 5. Black hole spacetimes: testing numerical relativity David H. Bernstein, David W. Hobill and Larry L. Smarr; 6. Three dimensional initial data of numerical relativity Ken-ichi Oohara and Takashi Nakamura; 7. Initial data for collisions of black holes and other gravitational miscellany James W. York, Jr.; 8. Analytic-numerical matching for gravitational waveform extraction Andrew M. Abrahams; 9. Supernovae, gravitational radiation and the quadrupole formula L. S. Finn; 10. Gravitational radiation from perturbations of stellar core collapse models Edward Seidel and Thomas Moore; 11. General relativistic implicit radiation hydrodynamics in polar sliced space-time Paul J. Schinder; 12. General relativistic radiation hydrodynamics in spherically symmetric spacetimes A. Mezzacappa and R. A. Matzner; 13. Constraint preserving transport for magnetohydrodynamics John F. Hawley and Charles R. Evans; 14. Enforcing the momentum constraints during axisymmetric spacelike simulations Charles R. Evans; 15. Experiences with an adaptive mesh refinement algorithm in numerical relativity Matthew W. Choptuik; 16. The multigrid technique Gregory B. Cook; 17. Finite element methods in numerical relativity P. J. Mann; 18. Pseudo-spectral methods applied to gravitational collapse Silvano Bonazzola and Jean-Alain Marck; 19. Methods in 3D numerical relativity Takashi Nakamura and Ken-ichi Oohara; 20. Nonaxisymmetric rotating gravitational collapse and gravitational radiation Richard F. Stark; 21. Nonaxisymmetric neutron star collisions: initial results using smooth particle hydrodynamics

  10. Clinical aspects of telemedicine

    NASA Technical Reports Server (NTRS)

    Merrell, Ronald C.

    1991-01-01

    Communication among physicians is an essential in order to combine our experiences for the elucidation and application of new knowledge and for the accurate and uniform application of established medical practice. This communication requires an adequate understanding of the culture of the patient and the social context of disease and indeed the culture of the physician. Malnutrition in Bangladesh means caloric insufficiency, and a program to lower cholesterol would be impertinent, while a program to enhance the nutrition of patients in Texas by an international effort to import more grain would be ludicrous. In the same vein a public health effort to combat alcoholic cirrhosis in Mecca would be as silly as a program to increase fiber in the diet of the Bantu. Clinical communication must acknowledge the culture of the issue at hand and the differences in the experiential base of the physicians. Not only do geography and culture affect the potential differences in the experiential bases, but the world utilizes very different traditions of education and science in training physicians. We are influenced by the diseases we treat, and learn to look for the expected at least as much as we are attentive to the unexpected. A physician in Siberia would be much more likely to recognize frostbite than one from Buenos Aires, and the Argentine doctor would much more likely consider Chaga's Disease to explain abdominal pain than a colleague in Zurich. Beyond these obvious issues in communication among physicians we must deal with the many languages and idioms used in the world. An overview of using Telemedicine SpaceBridge after the earthquake in the Republic of Armenia in 1988 is presented.

  11. Emotional processing affects movement speed.

    PubMed

    Hälbig, Thomas D; Borod, Joan C; Frisina, Pasquale G; Tse, Winona; Voustianiouk, Andrei; Olanow, C Warren; Gracies, Jean-Michel

    2011-09-01

    Emotions can affect various aspects of human behavior. The impact of emotions on behavior is traditionally thought to occur at central, cognitive and motor preparation stages. Using EMG to measure the effects of emotion on movement, we found that emotional stimuli differing in valence and arousal elicited highly specific effects on peripheral movement time. This result has conceptual implications for the emotion-motion link and potentially practical implications for neurorehabilitation and professional environments where fast motor reactions are critical.

  12. Numerical and experimental approaches to simulate soil clogging in porous media

    NASA Astrophysics Data System (ADS)

    Kanarska, Yuliya; LLNL Team

    2012-11-01

    Failure of a dam by erosion ranks among the most serious accidents in civil engineering. The best way to prevent internal erosion is using adequate granular filters in the transition areas where important hydraulic gradients can appear. In case of cracking and erosion, if the filter is capable of retaining the eroded particles, the crack will seal and the dam safety will be ensured. A finite element numerical solution of the Navier-Stokes equations for fluid flow together with Lagrange multiplier technique for solid particles was applied to the simulation of soil filtration. The numerical approach was validated through comparison of numerical simulations with the experimental results of base soil particle clogging in the filter layers performed at ERDC. The numerical simulation correctly predicted flow and pressure decay due to particle clogging. The base soil particle distribution was almost identical to those measured in the laboratory experiment. To get more precise understanding of the soil transport in granular filters we investigated sensitivity of particle clogging mechanisms to various aspects such as particle size ration, the amplitude of hydraulic gradient, particle concentration and contact properties. By averaging the results derived from the grain-scale simulations, we investigated how those factors affect the semi-empirical multiphase model parameters in the large-scale simulation tool. The Department of Homeland Security Science and Technology Directorate provided funding for this research.

  13. Robots in Space -Psychological Aspects

    NASA Technical Reports Server (NTRS)

    Sipes, Walter E.

    2006-01-01

    A viewgraph presentation on the psychological aspects of developing robots to perform routine operations associated with monitoring, inspection, maintenance and repair in space is shown. The topics include: 1) Purpose; 2) Vision; 3) Current Robots in Space; 4) Ground Based Robots; 5) AERCam; 6) Rotating Bladder Robot (ROBLR); 7) DART; 8) Robonaut; 9) Full Immersion Telepresence Testbed; 10) ERA; and 11) Psychological Aspects

  14. Magnitude knowledge: the common core of numerical development.

    PubMed

    Siegler, Robert S

    2016-05-01

    The integrated theory of numerical development posits that a central theme of numerical development from infancy to adulthood is progressive broadening of the types and ranges of numbers whose magnitudes are accurately represented. The process includes four overlapping trends: (1) representing increasingly precisely the magnitudes of non-symbolic numbers, (2) connecting small symbolic numbers to their non-symbolic referents, (3) extending understanding from smaller to larger whole numbers, and (4) accurately representing the magnitudes of rational numbers. The present review identifies substantial commonalities, as well as differences, in these four aspects of numerical development. With both whole and rational numbers, numerical magnitude knowledge is concurrently correlated with, longitudinally predictive of, and causally related to multiple aspects of mathematical understanding, including arithmetic and overall math achievement. Moreover, interventions focused on increasing numerical magnitude knowledge often generalize to other aspects of mathematics. The cognitive processes of association and analogy seem to play especially large roles in this development. Thus, acquisition of numerical magnitude knowledge can be seen as the common core of numerical development.

  15. Magnitude knowledge: the common core of numerical development.

    PubMed

    Siegler, Robert S

    2016-05-01

    The integrated theory of numerical development posits that a central theme of numerical development from infancy to adulthood is progressive broadening of the types and ranges of numbers whose magnitudes are accurately represented. The process includes four overlapping trends: (1) representing increasingly precisely the magnitudes of non-symbolic numbers, (2) connecting small symbolic numbers to their non-symbolic referents, (3) extending understanding from smaller to larger whole numbers, and (4) accurately representing the magnitudes of rational numbers. The present review identifies substantial commonalities, as well as differences, in these four aspects of numerical development. With both whole and rational numbers, numerical magnitude knowledge is concurrently correlated with, longitudinally predictive of, and causally related to multiple aspects of mathematical understanding, including arithmetic and overall math achievement. Moreover, interventions focused on increasing numerical magnitude knowledge often generalize to other aspects of mathematics. The cognitive processes of association and analogy seem to play especially large roles in this development. Thus, acquisition of numerical magnitude knowledge can be seen as the common core of numerical development. PMID:27074723

  16. Toward Scientific Numerical Modeling

    NASA Technical Reports Server (NTRS)

    Kleb, Bil

    2007-01-01

    Ultimately, scientific numerical models need quantified output uncertainties so that modeling can evolve to better match reality. Documenting model input uncertainties and verifying that numerical models are translated into code correctly, however, are necessary first steps toward that goal. Without known input parameter uncertainties, model sensitivities are all one can determine, and without code verification, output uncertainties are simply not reliable. To address these two shortcomings, two proposals are offered: (1) an unobtrusive mechanism to document input parameter uncertainties in situ and (2) an adaptation of the Scientific Method to numerical model development and deployment. Because these two steps require changes in the computational simulation community to bear fruit, they are presented in terms of the Beckhard-Harris-Gleicher change model.

  17. Entropy Splitting and Numerical Dissipation

    NASA Technical Reports Server (NTRS)

    Yee, H. C.; Vinokur, M.; Djomehri, M. J.

    1999-01-01

    A rigorous stability estimate for arbitrary order of accuracy of spatial central difference schemes for initial-boundary value problems of nonlinear symmetrizable systems of hyperbolic conservation laws was established recently by Olsson and Oliger (1994) and Olsson (1995) and was applied to the two-dimensional compressible Euler equations for a perfect gas by Gerritsen and Olsson (1996) and Gerritsen (1996). The basic building block in developing the stability estimate is a generalized energy approach based on a special splitting of the flux derivative via a convex entropy function and certain homogeneous properties. Due to some of the unique properties of the compressible Euler equations for a perfect gas, the splitting resulted in the sum of a conservative portion and a non-conservative portion of the flux derivative. hereafter referred to as the "Entropy Splitting." There are several potential desirable attributes and side benefits of the entropy splitting for the compressible Euler equations that were not fully explored in Gerritsen and Olsson. The paper has several objectives. The first is to investigate the choice of the arbitrary parameter that determines the amount of splitting and its dependence on the type of physics of current interest to computational fluid dynamics. The second is to investigate in what manner the splitting affects the nonlinear stability of the central schemes for long time integrations of unsteady flows such as in nonlinear aeroacoustics and turbulence dynamics. If numerical dissipation indeed is needed to stabilize the central scheme, can the splitting help minimize the numerical dissipation compared to its un-split cousin? Extensive numerical study on the vortex preservation capability of the splitting in conjunction with central schemes for long time integrations will be presented. The third is to study the effect of the non-conservative proportion of splitting in obtaining the correct shock location for high speed complex shock

  18. Cognitive and Representational Cues for Assigning Weight to Numerical Information in Decision-Making

    ERIC Educational Resources Information Center

    Rinne, Luke Frederick

    2010-01-01

    Incorporating relevant numerical information into decision-making is a fundamental and important aspect of numeracy. However, the process through which weight is assigned to particular numerical values is not well understood. The central theory proposed in this dissertation is that the weight assigned to numerical information may be conceptualized…

  19. Protostellar Jets: Numerical Simulations

    NASA Astrophysics Data System (ADS)

    Vitorino, B. F.; Jatenco-Pereira, V.; Opher, R.

    1998-11-01

    Numerical simulations of astrophysical jets have been made in order to study their collimation and internal structure. Recently Ouyed & Pudritz (1997) did numerical simulations of axi-simetric magnetocentrifugal jets from a keplerian acretion disk employing the eulerian finite difference code Zeus-2D. During their simulation, it was raised a steady state jet confirming a lot of results of the MHD winds steady state theory. Following this scenario we did tridimensional numerial simulations of this model allowing the jet, after a perturbation, evolve into a not steady state producing the helical features observed in some protostellar jets.

  20. Numerical multi-loop integrals and applications

    NASA Astrophysics Data System (ADS)

    Freitas, A.

    2016-09-01

    Higher-order radiative corrections play an important role in precision studies of the electroweak and Higgs sector, as well as for the detailed understanding of large backgrounds to new physics searches. For corrections beyond the one-loop level and involving many independent mass and momentum scales, it is in general not possible to find analytic results, so that one needs to resort to numerical methods instead. This article presents an overview of a variety of numerical loop integration techniques, highlighting their range of applicability, suitability for automatization, and numerical precision and stability. In a second part of this article, the application of numerical loop integration methods in the area of electroweak precision tests is illustrated. Numerical methods were essential for obtaining full two-loop predictions for the most important precision observables within the Standard Model. The theoretical foundations for these corrections will be described in some detail, including aspects of the renormalization, resummation of leading log contributions, and the evaluation of the theory uncertainty from missing higher orders.

  1. Aspect-Oriented Design with Reusable Aspect Models

    NASA Astrophysics Data System (ADS)

    Kienzle, Jörg; Al Abed, Wisam; Fleurey, Franck; Jézéquel, Jean-Marc; Klein, Jacques

    The idea behind Aspect-Oriented Modeling (AOM) is to apply aspect-oriented techniques to (software) models with the aim of modularizing crosscutting concerns. This can be done within different modeling notations, at different levels of abstraction, and at different moments during the software development process. This paper demonstrates the applicability of AOM during the software design phase by presenting parts of an aspect-oriented design of a crisis management system. The design solution proposed in this paper is based on the Reusable Aspect Models (RAM) approach, which allows a modeler to express the structure and behavior of a complex system using class, state and sequence diagrams encapsulated in several aspect models. The paper describes how the model of the "create mission" functionality of the server backend can be decomposed into 23 inter-dependent aspect models. The presentation of the design is followed by a discussion on the lessons learned from the case study. Next, RAM is compared to 8 other AOM approaches according to 6 criteria: language, concern composition, asymmetric and symmetric composition, maturity, and tool support. To conclude the paper, a discussion section points out the features of RAM that specifically support reuse.

  2. Insights into numerical cognition: considering eye-fixations in number processing and arithmetic.

    PubMed

    Mock, J; Huber, S; Klein, E; Moeller, K

    2016-05-01

    Considering eye-fixation behavior is standard in reading research to investigate underlying cognitive processes. However, in numerical cognition research eye-tracking is used less often and less systematically. Nevertheless, we identified over 40 studies on this topic from the last 40 years with an increase of eye-tracking studies on numerical cognition during the last decade. Here, we review and discuss these empirical studies to evaluate the added value of eye-tracking for the investigation of number processing. Our literature review revealed that the way eye-fixation behavior is considered in numerical cognition research ranges from investigating basic perceptual aspects of processing non-symbolic and symbolic numbers, over assessing the common representational space of numbers and space, to evaluating the influence of characteristics of the base-10 place-value structure of Arabic numbers and executive control on number processing. Apart from basic results such as reading times of numbers increasing with their magnitude, studies revealed that number processing can influence domain-general processes such as attention shifting-but also the other way round. Domain-general processes such as cognitive control were found to affect number processing. In summary, eye-fixation behavior allows for new insights into both domain-specific and domain-general processes involved in number processing. Based thereon, a processing model of the temporal dynamics of numerical cognition is postulated, which distinguishes an early stage of stimulus-driven bottom-up processing from later more top-down controlled stages. Furthermore, perspectives for eye-tracking research in numerical cognition are discussed to emphasize the potential of this methodology for advancing our understanding of numerical cognition. PMID:26847336

  3. Numerical Estimation in Preschoolers

    ERIC Educational Resources Information Center

    Berteletti, Ilaria; Lucangeli, Daniela; Piazza, Manuela; Dehaene, Stanislas; Zorzi, Marco

    2010-01-01

    Children's sense of numbers before formal education is thought to rely on an approximate number system based on logarithmically compressed analog magnitudes that increases in resolution throughout childhood. School-age children performing a numerical estimation task have been shown to increasingly rely on a formally appropriate, linear…

  4. Collapse of a Liquid Column: Numerical Simulation and Experimental Validation

    NASA Astrophysics Data System (ADS)

    Cruchaga, Marcela A.; Celentano, Diego J.; Tezduyar, Tayfun E.

    2007-03-01

    This paper is focused on the numerical and experimental analyses of the collapse of a liquid column. The measurements of the interface position in a set of experiments carried out with shampoo and water for two different initial column aspect ratios are presented together with the corresponding numerical predictions. The experimental procedure was found to provide acceptable recurrence in the observation of the interface evolution. Basic models describing some of the relevant physical aspects, e.g. wall friction and turbulence, are included in the simulations. Numerical experiments are conducted to evaluate the influence of the parameters involved in the modeling by comparing the results with the data from the measurements. The numerical predictions reasonably describe the physical trends.

  5. Linguistic Influence on Numerical Development.

    ERIC Educational Resources Information Center

    Park, Mangoo

    2000-01-01

    Discusses linguistic influence on children's numerical development. Describes and reviews recent papers that address the relationship between number naming systems and children's numerical concepts. (Contains 20 references.) (ASK)

  6. Colloidal aspects of texture perception.

    PubMed

    van Vliet, Ton; van Aken, George A; de Jongh, Harmen H J; Hamer, Rob J

    2009-08-30

    Recently, considerable attention has been given to the understanding of texture attributes that cannot directly be related to physical properties of food, such as creamy, crumbly and watery. The perception of these attributes is strongly related to the way the food is processed during food intake, mastication, swallowing of it and during the cleaning of the mouth after swallowing. Moreover, their perception is modulated by the interaction with other basic attributes, such as taste and aroma attributes (e.g. sourness and vanilla). To be able to link the composition and structure of food products to more complicated texture attributes, their initial physical/colloid chemical properties and the oral processing of these products must be well understood. Understanding of the processes in the mouth at colloidal length scales turned out to be essential to grasp the interplay between perception, oral physiology and food properties. In view of the huge differences in physical chemical properties between food products, it is practical to make a distinction between solid, semi-solid, and liquid food products. The latter ones are often liquid dispersions of emulsion droplets or particles in general. For liquid food products for instance flow behaviour and colloidal stability of dispersed particles play a main role in determining their textural properties. For most solid products stiffness and fracture behaviour in relation to water content are essential while for semi-solids a much larger range of mechanical properties will play a role. Examples of colloidal aspects of texture perception will be discussed for these three categories of products based on selected sensory attributes and/or relevant colloidal processes. For solid products some main factors determining crispness will be discussed. For crispiness of dry cellular solid products these are water content and the architecture of the product at mesoscopic length scales (20-1000 microm). In addition the distribution of

  7. Topological Aspects of Information Retrieval.

    ERIC Educational Resources Information Center

    Egghe, Leo; Rousseau, Ronald

    1998-01-01

    Discusses topological aspects of theoretical information retrieval, including retrieval topology; similarity topology; pseudo-metric topology; document spaces as topological spaces; Boolean information retrieval as a subsystem of any topological system; and proofs of theorems. (LRW)

  8. International Aspects of School Psychology

    ERIC Educational Resources Information Center

    Ziv, Avner

    1974-01-01

    This paper is concerned with various aspects of the philosophy and training of school psychologists in several countries around the world and offers some thoughts about the possible implications of the different approaches. (Author)

  9. Administrative Aspects of Human Experimentation.

    ERIC Educational Resources Information Center

    Irvine, George W.

    1992-01-01

    The following administrative aspects of scientific experimentation with human subjects are discussed: the definition of human experimentation; the distinction between experimentation and treatment; investigator responsibility; documentation; the elements and principles of informed consent; and the administrator's role in establishing and…

  10. A Digital Solar Aspect Sensor

    NASA Technical Reports Server (NTRS)

    Albus, James S.

    1961-01-01

    The solar aspect sensor described herein performs the analog-to-digital conversion of data optically. To accomplish this, it uses a binary "Gray code" light mask to produce a digital indication, in vehicle-fixed coordinates, of the elevation and azimuth angles of incident light from the sun. This digital solar aspect sensor system, in Explorer X, provided measurements of both elevation and azimuth angles to +/- 2 degrees at a distance of over 140,000 statute miles.

  11. Reciprocal Modulation of Cognitive and Emotional Aspects in Pianistic Performances

    PubMed Central

    Higuchi, Marcia K. Kodama; Fornari, José; Del Ben, Cristina M.; Graeff, Frederico G.; Leite, João Pereira

    2011-01-01

    Background High level piano performance requires complex integration of perceptual, motor, cognitive and emotive skills. Observations in psychology and neuroscience studies have suggested reciprocal inhibitory modulation of the cognition by emotion and emotion by cognition. However, it is still unclear how cognitive states may influence the pianistic performance. The aim of the present study is to verify the influence of cognitive and affective attention in the piano performances. Methods and Findings Nine pianists were instructed to play the same piece of music, firstly focusing only on cognitive aspects of musical structure (cognitive performances), and secondly, paying attention solely on affective aspects (affective performances). Audio files from pianistic performances were examined using a computational model that retrieves nine specific musical features (descriptors) – loudness, articulation, brightness, harmonic complexity, event detection, key clarity, mode detection, pulse clarity and repetition. In addition, the number of volunteers' errors in the recording sessions was counted. Comments from pianists about their thoughts during performances were also evaluated. The analyses of audio files throughout musical descriptors indicated that the affective performances have more: agogics, legatos, pianos phrasing, and less perception of event density when compared to the cognitive ones. Error analysis demonstrated that volunteers misplayed more left hand notes in the cognitive performances than in the affective ones. Volunteers also played more wrong notes in affective than in cognitive performances. These results correspond to the volunteers' comments that in the affective performances, the cognitive aspects of piano execution are inhibited, whereas in the cognitive performances, the expressiveness is inhibited. Conclusions Therefore, the present results indicate that attention to the emotional aspects of performance enhances expressiveness, but constrains

  12. Aspect Ratio Dependence in Magnetorotational Instability Shearing Box Simulations

    NASA Astrophysics Data System (ADS)

    Mignone, Andrea; Ferrari, Attilio; Bodo, Gianluigi; Rossi, Paola; Cattaneo, Fausto

    Three-dimensional numerical simulations of the magnetorotational instability in the shearing box approximation with a nonzero net flux are presented. By changing the size of the computational domain in the radial direction relative to the vertical box height, we find, in agreement with previous studies, that transport of angular momentum (associated with the so-called "channel solution") is strongly intermittent and maximized for boxes of unit aspect ratio. On the other hand, in boxes with larger aspect ratio the intermittent behavior disappears and angular momentum transport is inhibited.

  13. Two often disregarded aspects of Foucaultʼs pendulum

    NASA Astrophysics Data System (ADS)

    Pérez, José-Philippe; Pujol, Olivier

    2015-01-01

    This paper revisits the famous Foucault's pendulum by highlighting two often-disregarded aspects in mechanics courses. The first one concerns the existence of a local accelerated reference frame to express the law of dynamics without the Coriolis force. The second aspect deals with the geometrical phase that appears in pendulum dynamics. This last point, which could appear banal, should be related to analogous consideration in quantum physics. It is also linked to vectorial parallel transport of the pendulum angular momentum eigenvector. Numerical simulations with MATLAB are proposed.

  14. Psychiatric aspects of pain in cancer patients.

    PubMed

    Ozkan, Sedat

    2010-01-01

    The goal of this review is to discuss the psychiatric aspects of pain in cancer patients from a biopsychosocial approach. Pain in cancer patients is considered as a complex reaction causing severe suffering and involves many psychological aspects. It has many dimensions such as personality, affect, cognition and social relations. The pain experience may also be influenced by some psychological factors such as anxiety, depression and the meaning of pain. Therefore, a successful management of cancer pain requires a multidisciplinary approach. Since cancer pain is generally treated medically, the psychological impact of pain is often underestimated. However, cancer pain is usually related to high levels of psychological distress. Culture, as an important factor affecting cancer pain, will also be discussed during this review. It is crucial to understand cultural diversity in the treatment of cancer patients with pain. Research shows that a minority patients of various ethnicities have less control of their pain because of the miscommunication problem within the medical setting. By paying attention to patients' cultural diversities, problems such as miscommunication causing inadequate control of pain can be eliminated. In order to manage pain in cancer patients, cognitive-behavioral interventions may be integrated with pharmacotherapy. The main goal of these strategies is to provide a sense of control and better coping skills to deal with cancer. Patients' maladaptive thoughts or behaviors may cause physical and emotional stress. Main behavioral strategies include biofeedback, relaxation training, and hypnosis. Cognitive strategies include guided imagery, distraction, thought monitoring and problem solving. By discussing all of these aspects of cancer pain, the multidimensional characteristic of pain and the relation between cancer pain and psychiatric factors will be clarified. PMID:20590361

  15. Numerical Prediction of Dust. Chapter 10

    NASA Technical Reports Server (NTRS)

    Benedetti, Angela; Baldasano, J. M.; Basart, S.; Benincasa, F.; Boucher, O.; Brooks, M.; Chen, J. P.; Colarco, P. R.; Gong, S.; Huneeus, N.; Jones, L; Lu, S.; Menut, L.; Mulcahy, J.; Nickovic, S.; Morcrette, J.-J.; Perez, C.; Reid, J. S.; Sekiyama, T. T.; Tanaka, T.; Terradellas, E.; Westphal, D. L.; Zhang, X.-Y.; Zhou, C.-H.

    2013-01-01

    Covers the whole breadth of mineral dust research, from a scientific perspective Presents interdisciplinary work including results from field campaigns, satellite observations, laboratory studies, computer modelling and theoretical studies Explores the role of dust as a player and recorder of environmental change This volume presents state-of-the-art research about mineral dust, including results from field campaigns, satellite observations, laboratory studies, computer modelling and theoretical studies. Dust research is a new, dynamic and fast-growing area of science and due to its multiple roles in the Earth system, dust has become a fascinating topic for many scientific disciplines. Aspects of dust research covered in this book reach from timescales of minutes (as with dust devils, cloud processes, and radiation) to millennia (as with loess formation and oceanic sediments), making dust both a player and recorder of environmental change. The book is structured in four main parts that explore characteristics of dust, the global dust cycle, impacts of dust on the Earth system, and dust as a climate indicator. The chapters in these parts provide a comprehensive, detailed overview of this highly interdisciplinary subject. The contributions presented here cover dust from source to sink and describe all the processes dust particles undergo while travelling through the atmosphere. Chapters explore how dust is lifted and transported, how it affects radiation, clouds, regional circulations, precipitation and chemical processes in the atmosphere, and how it deteriorates air quality. The book explores how dust is removed from the atmosphere by gravitational settling, turbulence or precipitation, how iron contained in dust fertilizes terrestrial and marine ecosystems, and about the role that dust plays in human health. We learn how dust is observed, simulated using computer models and forecast. The book also details the role of dust deposits for climate reconstructions

  16. Hybrid undulator numerical optimization

    SciTech Connect

    Hairetdinov, A.H.; Zukov, A.A.

    1995-12-31

    3D properties of the hybrid undulator scheme arc studied numerically using PANDIRA code. It is shown that there exist two well defined sets of undulator parameters which provide either maximum on-axis field amplitude or minimal higher harmonics amplitude of the basic undulator field. Thus the alternative between higher field amplitude or pure sinusoidal field exists. The behavior of the undulator field amplitude and harmonics structure for a large set of (undulator gap)/(undulator wavelength) values is demonstrated.

  17. Numerical simulations in combustion

    NASA Technical Reports Server (NTRS)

    Chung, T. J.

    1989-01-01

    This paper reviews numerical simulations in reacting flows in general and combustion phenomena in particular. It is shown that use of implicit schemes and/or adaptive mesh strategies can improve convergence, stability, and accuracy of the solution. Difficulties increase as turbulence and multidimensions are considered, particularly when finite-rate chemistry governs the given combustion problem. Particular attention is given to the areas of solid-propellant combustion dynamics, turbulent diffusion flames, and spray droplet vaporization.

  18. Surface Similarity and Label Knowledge Impact Early Numerical Comparisons

    ERIC Educational Resources Information Center

    Mix, Kelly S.

    2008-01-01

    Previous research has reported that children's numerical equivalence judgments are affected by surface similarity and counting ability (e.g. Mix, Huttenlocher, & Levine, 1996; Siegel, 1973), a pattern that suggests categorization processes play a role in numerical development. However, because these studies involved memory for sets, large set…

  19. [Medical-social aspects of multiple sclerosis].

    PubMed

    Vermersch, P; Marissal, J P

    2001-09-01

    On a daily basis the quality of life of patients suffering from multiple sclerosis (MS) partially depends on social measures. These are not specific to MS. Patients often need to be helped by hospital or town social services for the numerous and complicated administrative steps to be taken. The information given to a patient is of prime importance concerning his rights, particularly his occupational rights. Many organisations have to be contacted to obtain financial and material aids, even if the latter are considered insufficient in many fields especially for improvements in accommodation. An invalidity card may entitle its holder to certain tax reductions. The competences of the COTOREP are wide-ranging and include the recognition of the handicapped worker, his training and his regarding at work, his orientation and admission into a specialised structure, the degree of his invalidity rate and should his handicap justify it, benefits such as the handicapped adults allowance and the compensatory third person's allowance. It is essential to adopt a multidisciplinary way when dealing with MS in order to provide a better care, experiments in specialised structures and networks are being undertaken. Numerous partners are taking part in these new approaches and patient associations may find their place there. Social aspects have to be taken into account as well in the way the cost of the disease is evaluated in terms of money and humanity. PMID:11787351

  20. Numerical wave interaction with tetrapods breakwater

    NASA Astrophysics Data System (ADS)

    Dentale, Fabio; Donnarumma, Giovanna; Carratelli, Eugenio Pugliese

    2014-12-01

    The paper provides some results of a new procedure to analyze the hydrodynamic aspects of the interactions between maritime emerged breakwaters and waves by integrating CAD and CFD. The structure is modeled in the numerical domain by overlapping individual three-dimensional elements (Tetrapods), very much like the real world or physical laboratory testing. Flow of the fluid within the interstices among concrete blocks is evaluated by integrating the RANS equations. The aim is to investigate the reliability of this approach as a design tool. Therefore, for the results' validation, the numerical run-up and reflection effects on virtual breakwater were compared with some empirical formulae and some similar laboratory tests. Here are presented the results of a first simple validation procedure. The validation shows that, at present, this innovative approach can be used in the breakwater design phase for comparison between several design solutions with a significant minor cost.

  1. Affect Consciousness in children with internalizing problems: Assessment of affect integration.

    PubMed

    Taarvig, Eva; Solbakken, Ole André; Grova, Bjørg; Monsen, Jon T

    2015-10-01

    Affect integration was operationalized through the Affect Consciousness (AC) construct as degrees of awareness, tolerance, nonverbal expression and conceptual expression of 11 affects. These aspects are assessed through a semi-structured Affect Consciousness Interview (ACI) and separate rating scales (Affect Consciousness Scales (ACSs)) developed for use in research and clinical work with adults with psychopathological disorders. Age-adjusted changes were made in the interview and rating system. This study explored the applicability of the adjusted ACI to a sample of 11-year-old children with internalizing problems through examining inter-rater reliability of the adjusted ACI, along with relationships between the AC aspects and aspects of mental health as symptoms of depression, symptoms of anxiety, social competence, besides general intelligence. Satisfactory inter-rater reliability was found, as well as consistent relationships between the AC aspects and the various aspects of mental health, a finding which coincides with previous research. The finding indicates that the attainment of the capacity to deal adaptively with affect is probably an important contributor to the development of adequate social competence and maybe in the prevention of psychopathology in children. The results indicate that the adjusted ACI and rating scales are useful tools in treatment planning with children at least from the age of 11 years.

  2. Community structure affects behavior.

    PubMed

    Jaenson, C

    1991-06-01

    AID's prevention efforts can benefit from taking into account 5 main aspects (KEPRA) of community structure identified by anthropologists: 1) kinship patterns, 2) economics, 3) politics, 4) religion, and 5) associations. For example, in Uganda among the Basoga and paternal aunt or senga is responsible for female sex education. Such culturally determined patterns need to be targeted in order to enhance education and effectiveness. Economics can reflect differing systems of family support through sexual means. The example given involves a poor family with a teenager in Thailand who exchanges a water buffalo or basic necessity for this daughter's prostitution. Politics must be considered because every society identifies people who have the power to persuade, influence, exchange resources, coerce, or in some way get people to do what is wanted. Utilizing these resources whether its ministers of health, factory owners, or peers is exemplified in the Monterey, Mexico factor floor supervisor and canteen worker introducing to workers the hows and whys of a new AID's education program. His peer status will command more respect than the director with direct authority. Religious beliefs have explanations for causes of sickness or disease, or provide instruction in sex practices. The example given is of a health workers in Uganda discussing AIDS with rural women by saying that we all know that disease and deaths are caused by spells. "But not AIDS - slim. AIDS is different." Associations can help provide educational, economic, and emotional assistance to the AID's effort or families affected.

  3. Fluid mechanics aspects of magnetic drug targeting.

    PubMed

    Odenbach, Stefan

    2015-10-01

    Experiments and numerical simulations using a flow phantom for magnetic drug targeting have been undertaken. The flow phantom is a half y-branched tube configuration where the main tube represents an artery from which a tumour-supplying artery, which is simulated by the side branch of the flow phantom, branches off. In the experiments a quantification of the amount of magnetic particles targeted towards the branch by a magnetic field applied via a permanent magnet is achieved by impedance measurement using sensor coils. Measuring the targeting efficiency, i.e. the relative amount of particles targeted to the side branch, for different field configurations one obtains targeting maps which combine the targeting efficiency with the magnetic force densities in characteristic points in the flow phantom. It could be shown that targeting efficiency depends strongly on the magnetic field configuration. A corresponding numerical model has been set up, which allows the simulation of targeting efficiency for variable field configuration. With this simulation good agreement of targeting efficiency with experimental data has been found. Thus, the basis has been laid for future calculations of optimal field configurations in clinical applications of magnetic drug targeting. Moreover, the numerical model allows the variation of additional parameters of the drug targeting process and thus an estimation of the influence, e.g. of the fluid properties on the targeting efficiency. Corresponding calculations have shown that the non-Newtonian behaviour of the fluid will significantly influence the targeting process, an aspect which has to be taken into account, especially recalling the fact that the viscosity of magnetic suspensions depends strongly on the magnetic field strength and the mechanical load. PMID:26415215

  4. Fluid mechanics aspects of magnetic drug targeting.

    PubMed

    Odenbach, Stefan

    2015-10-01

    Experiments and numerical simulations using a flow phantom for magnetic drug targeting have been undertaken. The flow phantom is a half y-branched tube configuration where the main tube represents an artery from which a tumour-supplying artery, which is simulated by the side branch of the flow phantom, branches off. In the experiments a quantification of the amount of magnetic particles targeted towards the branch by a magnetic field applied via a permanent magnet is achieved by impedance measurement using sensor coils. Measuring the targeting efficiency, i.e. the relative amount of particles targeted to the side branch, for different field configurations one obtains targeting maps which combine the targeting efficiency with the magnetic force densities in characteristic points in the flow phantom. It could be shown that targeting efficiency depends strongly on the magnetic field configuration. A corresponding numerical model has been set up, which allows the simulation of targeting efficiency for variable field configuration. With this simulation good agreement of targeting efficiency with experimental data has been found. Thus, the basis has been laid for future calculations of optimal field configurations in clinical applications of magnetic drug targeting. Moreover, the numerical model allows the variation of additional parameters of the drug targeting process and thus an estimation of the influence, e.g. of the fluid properties on the targeting efficiency. Corresponding calculations have shown that the non-Newtonian behaviour of the fluid will significantly influence the targeting process, an aspect which has to be taken into account, especially recalling the fact that the viscosity of magnetic suspensions depends strongly on the magnetic field strength and the mechanical load.

  5. Misperception of aspect ratio in binocularly viewed surfaces.

    PubMed

    Hibbard, Paul B; Goutcher, Ross; O'Kane, Lisa M; Scarfe, Peter

    2012-10-01

    The horizontal-vertical illusion, in which the vertical dimension is overestimated relative to the horizontal direction, has been explained in terms of the statistical relationship between the lengths of lines in the world, and the lengths of their projections onto the retina (Howe & Purves, 2002). The current study shows that this illusion affects the apparent aspect ratio of shapes, and investigates how it interacts with binocular cues to surface slant. One way in which statistical information could give rise to the horizontal-vertical illusion would be through prior assumptions about the distribution of slant. This prior would then be expected to interact with retinal cues to slant. We determined the aspect ratio of stereoscopically viewed ellipses that appeared circular. We show that observers' judgements of aspect ratio were affected by surface slant, but that the largest image vertical:horizontal aspect ratio that was considered to be a surface with a circular profile was always found for surfaces close to fronto-parallel. This is not consistent with a Bayesian model in which the horizontal-vertical illusion arises from a non-uniform prior probability distribution for slant. Rather, we suggest that assumptions about the slant of surfaces affect apparent aspect ratio in a manner that is more heuristic, and partially dissociated from apparent slant. PMID:22925917

  6. Predicting polarization performance of high-numerical aperture inspection lenses

    NASA Astrophysics Data System (ADS)

    Fahr, Stephan; Werschnik, Jan; Bening, Matthias; Uhlendorf, Kristina

    2015-09-01

    Along the course of increasing through-put and improving signal to noise ratio in optical wafer and mask inspection, demands on wave front aberrations and polarization characteristics are ever increasing. The system engineers and optical designers involved in the development of such optical systems will be responsible for specifying the quality of the optical material and the mechanical tolerances. Among optical designers it is well established how to estimate the wave front error of assembled and adjusted optical devices via sensitivity or Monte-Carlo analysis. However, when compared with the scalar problem of wave front estimation, the field of polarization control deems to pose a more complex problem due to its vectorial nature. Here we show our latest results in how to model polarization affecting aspects. In the realm of high numerical aperture (NA) inspection optics we will focus on the impact of coatings, stress induced birefringence due to non-perfect lens mounting, and finally the birefringence of the optical material. With all these tools at hand, we have a more complete understanding of the optical performance of our assembled optical systems. Moreover, we are able to coherently develop optical systems meeting demanding wave front criteria as well as high end polarization specifications.

  7. Numerical Analysis Objects

    NASA Astrophysics Data System (ADS)

    Henderson, Michael

    1997-08-01

    The Numerical Analysis Objects project (NAO) is a project in the Mathematics Department of IBM's TJ Watson Research Center. While there are plenty of numerical tools available today, it is not an easy task to combine them into a custom application. NAO is directed at the dual problems of building applications from a set of tools, and creating those tools. There are several "reuse" projects, which focus on the problems of identifying and cataloging tools. NAO is directed at the specific context of scientific computing. Because the type of tools is restricted, problems such as tools with incompatible data structures for input and output, and dissimilar interfaces to tools which solve similar problems can be addressed. The approach we've taken is to define interfaces to those objects used in numerical analysis, such as geometries, functions and operators, and to start collecting (and building) a set of tools which use these interfaces. We have written a class library (a set of abstract classes and implementations) in C++ which demonstrates the approach. Besides the classes, the class library includes "stub" routines which allow the library to be used from C or Fortran, and an interface to a Visual Programming Language. The library has been used to build a simulator for petroleum reservoirs, using a set of tools for discretizing nonlinear differential equations that we have written, and includes "wrapped" versions of packages from the Netlib repository. Documentation can be found on the Web at "http://www.research.ibm.com/nao". I will describe the objects and their interfaces, and give examples ranging from mesh generation to solving differential equations.

  8. Games, Gaming, and Gamification: Some Aspects of Motivation

    ERIC Educational Resources Information Center

    Hanson-Smith, Elizabeth

    2016-01-01

    Unsupported claims have been made for the use of games in education and the gamification (game-like aspects, such as scores and point goals) of various learning elements. This brief article examines what may be the motivational basis of gaming and how it can affect students' behavior and ultimate success.

  9. Multilingual Aspects of Fluency Disorders. Communication Disorders across Languages

    ERIC Educational Resources Information Center

    Howell, Peter; Van Borsel, John

    2011-01-01

    This book contains contributions by scholars working on diverse aspects of speech who bring their findings to bear on the practical issue of how to treat stuttering in different language groups and in multilingual speakers. The book considers classic issues in speech production research, as well as whether regions of the brain that are affected in…

  10. A numerical methodology for the Painlevé equations

    NASA Astrophysics Data System (ADS)

    Fornberg, Bengt; Weideman, J. A. C.

    2011-07-01

    The six Painlevé transcendents PI - PVI have both applications and analytic properties that make them stand out from most other classes of special functions. Although they have been the subject of extensive theoretical investigations for about a century, they still have a reputation for being numerically challenging. In particular, their extensive pole fields in the complex plane have often been perceived as 'numerical mine fields'. In the present work, we note that the Painlevé property in fact provides the opportunity for very fast and accurate numerical solutions throughout such fields. When combining a Taylor/Padé-based ODE initial value solver for the pole fields with a boundary value solver for smooth regions, numerical solutions become available across the full complex plane. We focus here on the numerical methodology, and illustrate it for the PI equation. In later studies, we will concentrate on mathematical aspects of both the PI and the higher Painlevé transcendents.

  11. Numerical modeling of suspended sediment due to deep-sea mining

    NASA Astrophysics Data System (ADS)

    Jankowski, J. A.; Malcherek, A.; Zielke, W.

    1996-02-01

    A numerical model was developed in order to estimate the residence time of a sediment plume generated by potential deep-sea mining activities, with special attention to discharges in the bottom boundary layer. The site of the Disturbance and Recolonization Experiment (DISCOL) in the Peru Basin in the southeast Pacific Ocean was chosen as a case study. The model includes the actual bathymetry, as well as the characteristic flow patterns of this region. Various aspects affecting the transport and sedimentation of the plume, such as stratification, flocculation in a sediment-laden water column, and the hydrodynamics are discussed in conjunction with field data and studied with the overall aim of providing a reliable risk assessment of deep-sea mining environmental impacts.

  12. Numerical Propulsion System Simulation

    NASA Technical Reports Server (NTRS)

    Naiman, Cynthia

    2006-01-01

    The NASA Glenn Research Center, in partnership with the aerospace industry, other government agencies, and academia, is leading the effort to develop an advanced multidisciplinary analysis environment for aerospace propulsion systems called the Numerical Propulsion System Simulation (NPSS). NPSS is a framework for performing analysis of complex systems. The initial development of NPSS focused on the analysis and design of airbreathing aircraft engines, but the resulting NPSS framework may be applied to any system, for example: aerospace, rockets, hypersonics, power and propulsion, fuel cells, ground based power, and even human system modeling. NPSS provides increased flexibility for the user, which reduces the total development time and cost. It is currently being extended to support the NASA Aeronautics Research Mission Directorate Fundamental Aeronautics Program and the Advanced Virtual Engine Test Cell (AVETeC). NPSS focuses on the integration of multiple disciplines such as aerodynamics, structure, and heat transfer with numerical zooming on component codes. Zooming is the coupling of analyses at various levels of detail. NPSS development includes capabilities to facilitate collaborative engineering. The NPSS will provide improved tools to develop custom components and to use capability for zooming to higher fidelity codes, coupling to multidiscipline codes, transmitting secure data, and distributing simulations across different platforms. These powerful capabilities extend NPSS from a zero-dimensional simulation tool to a multi-fidelity, multidiscipline system-level simulation tool for the full development life cycle.

  13. Confidence in Numerical Simulations

    SciTech Connect

    Hemez, Francois M.

    2015-02-23

    This PowerPoint presentation offers a high-level discussion of uncertainty, confidence and credibility in scientific Modeling and Simulation (M&S). It begins by briefly evoking M&S trends in computational physics and engineering. The first thrust of the discussion is to emphasize that the role of M&S in decision-making is either to support reasoning by similarity or to “forecast,” that is, make predictions about the future or extrapolate to settings or environments that cannot be tested experimentally. The second thrust is to explain that M&S-aided decision-making is an exercise in uncertainty management. The three broad classes of uncertainty in computational physics and engineering are variability and randomness, numerical uncertainty and model-form uncertainty. The last part of the discussion addresses how scientists “think.” This thought process parallels the scientific method where by a hypothesis is formulated, often accompanied by simplifying assumptions, then, physical experiments and numerical simulations are performed to confirm or reject the hypothesis. “Confidence” derives, not just from the levels of training and experience of analysts, but also from the rigor with which these assessments are performed, documented and peer-reviewed.

  14. Gender Aspects of Human Security

    ERIC Educational Resources Information Center

    Moussa, Ghada

    2008-01-01

    The chapter deals with the gender dimensions in human security through focusing on the relationship between gender and human security, first manifested in international declarations and conventions, and subsequently evolving in world women conferences. It aims at analysing the various gender aspects in its relation to different human security…

  15. Aspects of Spirituality in Adolescents

    ERIC Educational Resources Information Center

    Bussing, Arndt; Foller-Mancini, Axel; Gidley, Jennifer; Heusser, Peter

    2010-01-01

    This paper analyses which aspects of spirituality are valued by adolescents, and how they are interconnected with youths' life satisfaction and "self-centeredness". The participants were 254 adolescents (11th grade) of four different high schools from west Germany. After re-validation of the 6-factorial student's version of the ASP questionnaire…

  16. Computational aspects of multibody dynamics

    NASA Technical Reports Server (NTRS)

    Park, K. C.

    1989-01-01

    Computational aspects are addressed which impact the requirements for developing a next generation software system for flexible multibody dynamics simulation which include: criteria for selecting candidate formulation, pairing of formulations with appropriate solution procedures, need for concurrent algorithms to utilize computer hardware advances, and provisions for allowing open-ended yet modular analysis modules.

  17. Legal Aspects of Pupil Transportation.

    ERIC Educational Resources Information Center

    Mawdsley, Ralph D.

    The legal aspects of pupil transportation are examined, including the liability of various factions for transportation decisions and the duty of school districts to provide adequate transportation. Discussed are court decisions dealing with such complex topics as transportation of special education students, transportation for purpose of…

  18. Behavioral Aspects of Marijuana Use.

    ERIC Educational Resources Information Center

    Paulson, Patricia

    This paper examines the behavioral aspects of marijuana use. The focus of the study was to investigate the attitudes and practices toward drugs by users and non-users and the relationship of these attitudes and practices to selected psychosocial factors. A survey instrument in the form of an anonymous questionnaire was developed and administered…

  19. Legal Aspects of the Web.

    ERIC Educational Resources Information Center

    Borrull, Alexandre Lopez; Oppenheim, Charles

    2004-01-01

    Presents a literature review that covers the following topics related to legal aspects of the Web: copyright; domain names and trademarks; linking, framing, caching, and spamdexing; patents; pornography and censorship on the Internet; defamation; liability; conflict of laws and jurisdiction; legal deposit; and spam, i.e., unsolicited mails.…

  20. Pragmatic Aspects of Scalar Modifiers

    ERIC Educational Resources Information Center

    Sawada, Osamu

    2010-01-01

    This dissertation investigates the pragmatic aspects of scalar modifiers from the standpoint of the interface between semantics and pragmatics, focusing on (i) the (non) parallelism between the truth-conditional scalar modifiers and the non-truth-conditional scalar modifiers, (ii) the compositionality and dimensionality of non-truth-conditional…

  1. Psychological Aspects of Chronic Pain

    PubMed Central

    Jacobs, Rosevelt

    1983-01-01

    Since its inception in June 1979, over 500 patients have been treated at the King/Drew Pain Center in Los Angeles. Based upon the treatment and observations of this patient group, this paper describes the psychologic aspects in patients suffering from chronic abdominal pain, low back pain, phantom limb pain, chest pain, and arthritic pain. PMID:6864816

  2. The Maya Project: Numerical Simulations of Black Hole Collisions

    NASA Astrophysics Data System (ADS)

    Smith, Kenneth; Calabrese, Gioel; Garrison, David; Kelly, Bernard; Laguna, Pablo; Lockitch, Keith; Pullin, Jorge; Shoemaker, Deirdre; Tiglio, Manuel

    2001-04-01

    The main objective of the MAYA project is the development of a numerical code to solve the vacuum Einstein's field equations for spacetimes containing multiple black hole singularities. Incorporating knowledge gained from previous similar efforts (Binary Black Holes Alliance and the AGAVE project) as well as one-dimensional numerical studies, MAYA has been built from the ground up within the architecture of Cactus 4.0, with particular attention paid to the software engineering aspects of code development. The goal of this new effort is to ultimately have a robust, efficient, readable, and stable numerical code for black hole evolution. This poster presents an overview of the project, focusing on the innovative aspects of the project as well as its current development status.

  3. Affect, Albert Ellis, and Rational-Emotive Therapy.

    ERIC Educational Resources Information Center

    Morris, G. Barry

    1989-01-01

    Contends affect is integral component of Rational Emotive Therapy model. Reviews affective aspect of the model in terms of theoretical constructs and therapeutic techniques. Makes references to author-observed interactions of Albert Ellis and describes his life-style to permit inferences regarding the role of affect. Includes commentary by Ellis…

  4. Institutional and socioeconomic aspects of water supply

    NASA Astrophysics Data System (ADS)

    Rauchenschwandtner, H.; Pachel, M.

    2012-04-01

    Institutional and socioeconomic aspects of water supply Within the project CC-WaterS the participating researchers of the Vienna University of Economics and B.A. have been responsible for the analysis of the socioeconomic aspects related to water supply and climate change, the assessment of future water demands in the City of Vienna, as well as an estimation of economic consequences of possible water shortages and possible scope for the introduction of new legal guidelines. The institutional and socioeconomic dimensions of drinking water and sanitation systems are being examined by utilisation of different prognostic scenarios in order to assess future costs of water provisioning and future demands of main water users, thus providing an information basis and recommendations for policy and decision makers in the water sector. These dimensions, for example, include EU legislation - especially the Water Framework Directive -, national legislations and strategies targeted at achieving sustainability in water usage, best practices and different forms of regulating water markets, and an analysis of the implications of demographic change. As a basis this task encompasses research of given institutional, social, and legal-political structures in the area of water supply. In this course we provide an analysis of the structural characteristics of water markets, the role of water prices, the increasing perception of water as an economic good as well as implications thereof, the public awareness in regard to climate change and water resources, as well as related legal aspects and involved actors from regional to international level; and show how water resources and the different systems of water provisioning are affected by (ideological) conflicts on various levels. Furthermore, and in order to provide a solid basis for management recommendations related to climate change and water supply, an analytical risk-assessment framework based on the concepts of new institutional

  5. Rythmos Numerical Integration Package

    2006-09-01

    Rythmos numerically integrates transient differential equations. The differential equations can be explicit or implicit ordinary differential equations ofr formulated as fully implicit differential-algebraic equations. Methods include backward Euler, forward Euler, explicit Runge-Kutta, and implicit BDF at this time. Native support for operator split methods and strict modularity are strong design goals. Forward sensitivity computations will be included in the first release with adjoint sensitivities coming in the near future. Rythmos heavily relies on Thyra formore » linear algebra and nonlinear solver interfaces to AztecOO, Amesos, IFPack, and NOX in Tilinos. Rythmos is specially suited for stiff differential equations and thos applictions where operator split methods have a big advantage, e.g. Computational fluid dynamics, convection-diffusion equations, etc.« less

  6. Learning numerical progressions.

    PubMed

    Vitz, P C; Hazan, D N

    1974-01-01

    Learning of simple numerical progressions and compound progressions formed by combining two or three simple progressions is investigated. In two experiments, time to solution was greater for compound vs simple progressions; greater the higher the progression's solution level; and greater if the progression consisted of large vs small numbers. A set of strategies is proposed to account for progression learning based on the assumption S computes differences between integers, differences between differences, etc., in a hierarchical fashion. Two measures of progression difficulty, each a summary of the strategies, are proposed; C1 is a count of the number of differences needed to solve a progression; C2 is the same count with higher level differences given more weight. The measures accurately predict in both experiments the mean time to solve 16 different progressions with C2 being somewhat superior. The measures also predict the learning difficulty of 10 other progressions reported by Bjork (1968).

  7. Rythmos Numerical Integration Package

    SciTech Connect

    Coffey, Todd S.; Bartlett, Roscoe A.

    2006-09-01

    Rythmos numerically integrates transient differential equations. The differential equations can be explicit or implicit ordinary differential equations ofr formulated as fully implicit differential-algebraic equations. Methods include backward Euler, forward Euler, explicit Runge-Kutta, and implicit BDF at this time. Native support for operator split methods and strict modularity are strong design goals. Forward sensitivity computations will be included in the first release with adjoint sensitivities coming in the near future. Rythmos heavily relies on Thyra for linear algebra and nonlinear solver interfaces to AztecOO, Amesos, IFPack, and NOX in Tilinos. Rythmos is specially suited for stiff differential equations and thos applictions where operator split methods have a big advantage, e.g. Computational fluid dynamics, convection-diffusion equations, etc.

  8. Psychological Aspects of Chronic Musculoskeletal Pain

    PubMed Central

    Crofford, Leslie J.

    2015-01-01

    Chronic musculoskeletal pain, by its very nature, will be associated with negative emotions and psychological distress. There are individual differences in personality, coping skills, behavioral adaptation, and social support that dramatically alter the psychological outcomes of patients with chronic pain. Patients that have an aspect of central pain amplification associated with mechanical or inflammatory pain and patients with fibromyalgia (FM) are likely to exhibit higher levels of psychological distress and illness behaviors. This manuscript will discuss several different constructs for the association between chronic pain, central pain amplification, and psychological distress. The first key question addresses mechanisms shared in common between chronic pain and mood disorders, including the individual factors that influence psychological comorbidity. Second, how pain affects mood and vice versa. Finally, the utility of cognitive behavioral approaches to the management of chronic pain symptoms will be discussed. PMID:26267008

  9. Quality aspects of digital radiography in general dental practice.

    PubMed

    Hellén-Halme, Kristina

    2007-01-01

    The number of dentists who have converted from conventional film radiography to digital radiography continues to grow. A digital system has numerous advantages, but there are also many new aspects to consider. The overall aim of this thesis was to study how digital radiography was used in general dental practices. The specific aims were to study how different factors affected image quality. To determine whether there were any differences in image quality between conventional film radiographs and digital radiographs, 4863 images (540 cases) were evaluated. The cases had been sent to the Swedish Dental Insurance Office for prior treatment approval. The image quality of digital radiographs was found to be significantly lower than that of film radiographs. This result led to a questionnaire study of dentists experienced in digital radiography. In 2003, a questionnaire was sent to the 139 general practice dentists who worked with digital radiography in Skine, Sweden; the response rate was 94%. Many general practice dentists had experienced several problems (65%), and less than half of the digital systems (40%) underwent some kind of quality control. One of the weaker links in the technical chain of digital radiography appeared to be the monitor. A field study to 19 dentists at their clinics found that the brightness and contrast settings of the monitors had to be adjusted to obtain the subjectively best image quality. The ambient light in the evaluation room was also found to affect the diagnostic outcome of low-contrast patterns in radiographs. To evaluate the effects of ambient light and technical adjustments of the monitor, a study using standardised set-ups was designed. Seven observers evaluated radiographs of 100 extracted human teeth for approximal caries under five different combinations of brightness and contrast settings on two different occasions with high and low ambient light levels in the evaluation room. The ability to diagnose carious lesions was found

  10. Developmental Change in Numerical Estimation

    ERIC Educational Resources Information Center

    Slusser, Emily B.; Santiago, Rachel T.; Barth, Hilary C.

    2013-01-01

    Mental representations of numerical magnitude are commonly thought to undergo discontinuous change over development in the form of a "representational shift." This idea stems from an apparent categorical shift from logarithmic to linear patterns of numerical estimation on tasks that involve translating between numerical magnitudes and spatial…

  11. Personality aspects in multiple sclerosis.

    PubMed

    Diana, R; Grosz, A; Mancini, E

    1985-12-01

    To test the claim that peculiar personality bias is detectable in multiple sclerosis (MS) we used the Szondi test to investigate the psychodynamic aspects of 110 MS patients in comparison with 200 healthy subjects. MS patients appeared to have a greater need for love in a passive form than normal people, rigid defense mechanisms, difficulty in resolving their inner conflicts either by sublimation or by internalization of satisfactory new emotional experiences, feelings of autoaggressiveness, and many symptoms of depression. Some of these aspects correlate with the severity of the disease, others seem to date back to early childhood as peculiar personality patterns. An investigation of childhood events in 110 controls confirmed that MS patients had had many more unhappy experiences in childhood than might commonly be expected. Further, the oft-reported psychiatric troubles preceding MS clinical onset suggest that at least in some MS patients there are specific gaps in personality structure dating back to early phases of their development. PMID:4086262

  12. Liposarcome dorsal: aspect clinique rare

    PubMed Central

    Agbessi, Odry; Arrob, Adil; Fiqhi, Kamal; Khalfi, Lahcen; Nassih, Mohammed; El Khatib, Karim

    2015-01-01

    Décrit la première fois par Virchow en 1860, le liposarcome est une tumeur mésenchymateuse rare. Cette rareté est relative car les liposarcomes représentent quand même 14 à 18% de l'ensemble des tumeurs malignes des parties molles et ils constituent le plus fréquent des sarcomes des parties molles. Pour la majorité des auteurs, il ne se développerait jamais sur un lipome ou une lipomatose préexistant. Nous rapportons un cas de volumineux liposarcome de la face dorsale du tronc. L'histoire de la maladie, l'aspect clinique inhabituel « de tumeur dans tumeur », l'aspect de la pièce opératoire nous fait évoquer la possibilité de la transformation maligne d'un lipome bénin préexistant. PMID:26113914

  13. Tularaemia: clinical aspects in Europe.

    PubMed

    Maurin, Max; Gyuranecz, Miklós

    2016-01-01

    Tularaemia is a zoonotic disease caused by Francisella tularensis, a Gram-negative, facultative intracellular bacterium. Typically, human and animal infections are caused by F tularensis subspecies tularensis (type A) strains mainly in Canada and USA, and F tularensis subspecies holarctica (type B) strains throughout the northern hemisphere, including Europe. In the past, the epidemiological, clinical, therapeutic, and prognostic aspects of tularaemia reported in the English medical literature were mainly those that had been reported in the USA, where the disease was first described. Tularaemia has markedly changed in the past decade, and a large number of studies have provided novel data for the disease characteristics in Europe. In this Review we aim to emphasise the specific and variable aspects of tularaemia in different European countries. In particular, two natural lifecycles of F tularensis have been described in this continent, although not fully characterised, which are associated with different modes of transmission, clinical features, and public health burdens of tularaemia.

  14. Numerical and experimental predictions of fine-soil erosion, transport and trapping in embankment dam

    NASA Astrophysics Data System (ADS)

    Kanarska, Y.; Lomov, I.; Ezzedine, S. M.; Antoun, T. H.; Glascoe, L. G.

    2011-12-01

    A determination of the safety of dam structures requires the characterization of fine-soil erosion processes and the ability of filter layers to capture fine-soil particles to prevent dam failure. We investigated numerically and experimentally different aspects of this problem at a grain scale. The numerical method was based on Lagrange multiplier technique (Kanarska et al., 2011). The particle-particle interactions were implemented using explicit force-displacement interactions for frictional inelastic particles similar to the distinct element method (DEM) (Cundall and Strack, 1979), with some modifications using the volume of the overlapping region as the input to the contact forces. The first set of numerical tests was performed to describe the response of a granular bed to forcing by a fluid, which flows over the crack surface. We investigated how particle properties, such as size and shape, affect threshold values for critical shear stresses and mean velocities. A good agreement between numerical results and experiments was found. A general constitutive erosion law, critical shear stresses, and erosion velocities were derived and validated against the available experimental range of conditions for different particle sizes, particle shapes, and flow conditions. We confirmed that a linear relationship between particle mass fluxes and shear stresses well describes soil behavior. A second set of numerical and experimental tests to investigate sediment trapping in the filter layers was also performed. The laboratory experiments on soil transport and trapping in granular media were conducted in constant-head flow chamber filled with filter media. We investigated how particle properties and amplitude of the applied hydraulic gradient affect clogging criteria and changes in hydraulic conductivity of the medium. The numerical results were validated against available experimental data. We started with spherical particles. In the future, we are planning to investigate

  15. Practical aspects of corrosion fundamentals

    SciTech Connect

    Isaacs, H.S.

    1994-08-01

    Aspects important in corrosion have been introduced. They are: (a) ``Pourbaix Diagrams`` which consider thermodynamic stability of metals as a function of electrical potential and water pH; (b) the anodic interfacial reaction rates which depend on potential and accumulation of reaction products; (c) the prediction of polarization curves based on the kinetics and thermodynamics; and (d) localized corrosion models, as this form of corrosion is a major cause of corrosion failures.

  16. Legal aspects of satellite teleconferencing

    NASA Technical Reports Server (NTRS)

    Smith, D. D.

    1971-01-01

    The application of satellite communications for teleconferencing purposes is discussed. The legal framework within which such a system or series of systems could be developed is considered. The analysis is based on: (1) satellite teleconferencing regulation, (2) the options available for such a system, (3) regulatory alternatives, and (4) ownership and management aspects. The system is designed to provide a capability for professional education, remote medical diagnosis, business conferences, and computer techniques.

  17. Precision digital solar aspect sensor

    NASA Technical Reports Server (NTRS)

    Scherer, H. P.

    1972-01-01

    The development of a digital solar aspect sensor with a resolution of approximately 14 arc-seconds is discussed. An interpolation technique was used to generate the fine angle measurements. The sensor and its mode of operation are described. The electronic and mechanical design of the sensor were completed, and two flight units, one for the OAO 4 and the other for determining the attitude of a spinning spacecraft, are being fabricated.

  18. Extreme Low Aspect Ratio Stellarators

    NASA Astrophysics Data System (ADS)

    Moroz, Paul

    1997-11-01

    Recently proposed Spherical Stellarator (SS) concept [1] includes the devices with stellarator features and low aspect ratio, A <= 3.5, which is very unusual for stellarators (typical stellarators have A ≈ 7-10 or above). Strong bootstrap current and high-β equilibria are two distinguished elements of the SS concept leading to compact, steady-state, and efficient fusion reactor. Different coil configurations advantageous for the SS have been identified and analyzed [1-6]. In this report, we will present results on novel stellarator configurations which are unusual even for the SS approach. These are the extreme-low-aspect-ratio-stellarators (ELARS), with the aspect ratio A ≈ 1. We succeeded in finding ELARS configurations with extremely compact, modular, and simple design compatible with significant rotational transform (ι ≈ 0.1 - 0.15), large plasma volume, and good particle transport characteristics. [1] P.E. Moroz, Phys. Rev. Lett. 77, 651 (1996); [2] P.E. Moroz, Phys. Plasmas 3, 3055 (1996); [3] P.E. Moroz, D.B. Batchelor et al., Fusion Tech. 30, 1347 (1996); [4] P.E. Moroz, Stellarator News 48, 2 (1996); [5] P.E. Moroz, Plasma Phys. Reports 23, 502 (1997); [6] P.E. Moroz, Nucl. Fusion 37, No. 8 (1997). *Supported by DOE Grant No. DE-FG02-97ER54395.

  19. Thermodynamic Aspects of Tropical Cyclone Formation

    NASA Astrophysics Data System (ADS)

    Wang, Z.

    2012-12-01

    The thermodynamic aspects of tropical cyclone (TC) formation near the center of the wave pouch, a region of approximately closed Lagrangian circulation within the wave critical layer, are examined through diagnoses of a high-resolution numerical simulation and dropsonde data from a recent field campaign. It is found that the meso-β area near the pouch center is characterized by high saturation fraction, small difference in equivalent potential temperature (θe) between the surface and the middle troposphere, and a short incubation time scale. Updrafts tend to be more vigorous in this region, presumably due to reduced dry air entrainment, while downdrafts are not suppressed. The thermodynamic conditions near the pouch center are thus critically important for TC formation. The balanced responses to convective and stratiform heating at the pre-genesis stage are examined using the Sawyer-Eliassen equation. Deep convection is concentrated near the pouch center. The strong radial and vertical gradients of latent heat release effectively force the transverse circulation and spin up a surface proto-vortex near the pouch center. Stratiform heating induces modest mid-level inflow and very weak low-level outflow, which contributes to the mid-level spin-up without substantially spinning down the low-level circulation. The analysis of dropsonde data shows that the mid-level θe increases significantly near the pouch center one to two days prior to genesis but changes little away from the pouch center. This may indicate convective organization and the impending TC genesis. It also suggests that the critical information of TC genesis near the pouch center may be masked out if a spatial average is taken over the pouch scale. Time-radius plots of (a) saturation fraction (SF; units: %), (b) θe difference between 950 mb and 700 mb (950 mb "minus" 700 hPa; units: K), and (c) χm in the numerical model simulation of Felix.

  20. Guide to good practices for operations aspects of unique processes

    SciTech Connect

    1998-12-01

    This Guide to Good Practices is written to enhance understanding of, and provide direction for, Operations Aspects of Facility Chemistry and Unique Processes, Chapter XIII of Department of Energy (DOE) Order 5480.19, Conduct of Operations Requirements for DOE Facilities. The practices in this guide should be considered when planning or reviewing employee training and facility management programs. Contractors are advised to adopt procedures that meet the intent of DOE Order 5480.19. Operations Aspects of Unique Processes is an element of an effective Conduct of Operations program. The complexity and array of activities performed in DOE facilities dictate the necessity for all personnel to coordinate interrelated activities affecting unique processes.

  1. Numerical Relativity and Astrophysics

    NASA Astrophysics Data System (ADS)

    Lehner, Luis; Pretorius, Frans

    2014-08-01

    Throughout the Universe many powerful events are driven by strong gravitational effects that require general relativity to fully describe them. These include compact binary mergers, black hole accretion, and stellar collapse, where velocities can approach the speed of light and extreme gravitational fields (ΦNewt/c2≃1) mediate the interactions. Many of these processes trigger emission across a broad range of the electromagnetic spectrum. Compact binaries further source strong gravitational wave emission that could directly be detected in the near future. This feat will open up a gravitational wave window into our Universe and revolutionize our understanding of it. Describing these phenomena requires general relativity, and—where dynamical effects strongly modify gravitational fields—the full Einstein equations coupled to matter sources. Numerical relativity is a field within general relativity concerned with studying such scenarios that cannot be accurately modeled via perturbative or analytical calculations. In this review, we examine results obtained within this discipline, with a focus on its impact in astrophysics.

  2. How Coriolis meter design affects field performance

    SciTech Connect

    Levien, A.; Dudiak, A.

    1995-12-31

    Although many possibilities exist for the design of Coriolis flowmeters, a common set of fundamental physical principles affect practical meter design. Design criteria such as tube geometry, alloy section, operating frequencies, stress levels, and tubing wall thickness have varying impacts on meter performance. Additionally, field conditions such as changing temperature, pressure, pipeline stress and vibration affect measurement performance. The challenge created in Coriolis flow meter design is to maximize the sensitivity of the meter Coriolis forces, while minimizing the impact of outside environmental influences. Data are presented on the physical principles that affect Coriolis flowmeters, and how the various aspects of meter design influence field performance.

  3. Macroscopic aspects of interfacial reactions

    NASA Technical Reports Server (NTRS)

    Heckel, R. W.

    1976-01-01

    The extent of interdiffusion and formation of new phases is determined by the constitution diagram of the alloy system, the interdiffusion coefficients of the phases present, and the thermal conditions (temperature and time) associated with the bonding process and/or subsequent use of the bonded structure. In many instance, the kinetics of interdiffusion and phase formation can be predicted from known parameters using numerical methods and computer techniques. Predictions are compared with experimentally determined parameters for a variety of metallurgical alloy systems.

  4. A numerical simulation of finite-length Taylor-Couette flow

    NASA Technical Reports Server (NTRS)

    Streett, C. L.; Hussaini, M. Y.

    1988-01-01

    Results from numerical simulations of finite-length Taylor-Couette flow are presented. Included are time-accurate and steady-state studies of the change in the nature of the symmetric two-cell/asymmetric one-cell bifurcation with varying aspect ratio and of the Reynolds number/aspect ratio locus of the two-cell/four-cell bifurcation. Preliminary results from wavy-vortex simulations at low aspect ratios are also presented.

  5. Micromechanical aspects of granular ratcheting

    NASA Astrophysics Data System (ADS)

    Alonso-Marroquín, Fernando; Galindo-Torres, Sergio-Andres; Wang, Yucang

    2009-06-01

    The existence of granular ratcheting as a long-time behavior in granular materials is still under discussion in the scientific and engineering community. This behavior refers to the constant accumulation of permanent deformation per cycle, when the granular sample is subjected to loading-unloading stress cycles with amplitudes well bellow the yield limit. Ratcheting regimes are observed in both numerical and physical experiments. There is no controversy about the existence of ratcheting when the stress amplitudes reach the yield criterion. However, it is not clear whether this effect persists for loading amplitudes well bellow the yield limit, or whether there is a certain regime where no accumulation of deformation occurs. Early numerical simulations suggested that ratcheting may persist for extremely small loading amplitudes (Alonso-Marroquin and H. J. Herrmann, Rev. Lett. 92 5 (2004) 054301). More recent investigations drive to the conclusion that ratcheting at low stress amplitudes may be strongly influenced by the selection of the contact force (McNamara et al.. Phys. Rev. E 77 (3) (2008) 31304). Here we present a numerical investigation of the dependence of granular ratcheting on contact force in a packing of spheres using the Cundall-Strack model and the McNamara correction to the contact force. We conclude that ratcheting for spherical particles is strongly influenced by the McNamara correction. The question of the existence of genuine ratcheting for small cycles for non-spherical particles is still unsolved.

  6. Test aspects of the JPL Viterbi decoder

    NASA Technical Reports Server (NTRS)

    Breuer, M. A.

    1989-01-01

    The generation of test vectors and design-for-test aspects of the Jet Propulsion Laboratory (JPL) Very Large Scale Integration (VLSI) Viterbi decoder chip is discussed. Each processor integrated circuit (IC) contains over 20,000 gates. To achieve a high degree of testability, a scan architecture is employed. The logic has been partitioned so that very few test vectors are required to test the entire chip. In addition, since several blocks of logic are replicated numerous times on this chip, test vectors need only be generated for each block, rather than for the entire circuit. These unique blocks of logic have been identified and test sets generated for them. The approach employed for testing was to use pseudo-exhaustive test vectors whenever feasible. That is, each cone of logid is tested exhaustively. Using this approach, no detailed logic design or fault model is required. All faults which modify the function of a block of combinational logic are detected, such as all irredundant single and multiple stuck-at faults.

  7. On Numerical Aspects of Bayesian Model Selection in High and Ultrahigh-dimensional Settings

    PubMed Central

    Johnson, Valen E.

    2014-01-01

    This article examines the convergence properties of a Bayesian model selection procedure based on a non-local prior density in ultrahigh-dimensional settings. The performance of the model selection procedure is also compared to popular penalized likelihood methods. Coupling diagnostics are used to bound the total variation distance between iterates in an Markov chain Monte Carlo (MCMC) algorithm and the posterior distribution on the model space. In several simulation scenarios in which the number of observations exceeds 100, rapid convergence and high accuracy of the Bayesian procedure is demonstrated. Conversely, the coupling diagnostics are successful in diagnosing lack of convergence in several scenarios for which the number of observations is less than 100. The accuracy of the Bayesian model selection procedure in identifying high probability models is shown to be comparable to commonly used penalized likelihood methods, including extensions of smoothly clipped absolute deviations (SCAD) and least absolute shrinkage and selection operator (LASSO) procedures. PMID:24683431

  8. Computational and numerical aspects of using the integral equation method for adhesive layer fracture mechanics analysis

    SciTech Connect

    Giurgiutiu, V.; Ionita, A.; Dillard, D.A.; Graffeo, J.K.

    1996-12-31

    Fracture mechanics analysis of adhesively bonded joints has attracted considerable attention in recent years. A possible approach to the analysis of adhesive layer cracks is to study a brittle adhesive between 2 elastic half-planes representing the substrates. A 2-material 3-region elasticity problem is set up and has to be solved. A modeling technique based on the work of Fleck, Hutchinson, and Suo is used. Two complex potential problems using Muskelishvili`s formulation are set up for the 3-region, 2-material model: (a) a distribution of edge dislocations is employed to simulate the crack and its near field; and (b) a crack-free problem is used to simulate the effect of the external loading applied in the far field. Superposition of the two problems is followed by matching tractions and displacements at the bimaterial boundaries. The Cauchy principal value integral is used to treat the singularities. Imposing the traction-free boundary conditions over the entire crack length yielded a linear system of two integral equations. The parameters of the problem are Dundurs` elastic mismatch coefficients, {alpha} and {beta}, and the ratio c/H representing the geometric position of the crack in the adhesive layer.

  9. Numerical Aspects of Nonhydrostatic Implementations Applied to a Parallel Finite Element Tsunami Model

    NASA Astrophysics Data System (ADS)

    Fuchs, A.; Androsov, A.; Harig, S.; Hiller, W.; Rakowsky, N.

    2012-04-01

    Based on the jeopardy of devastating tsunamis and the unpredictability of such events, tsunami modelling as part of warning systems is still a contemporary topic. The tsunami group of Alfred Wegener Institute developed the simulation tool TsunAWI as contribution to the Early Warning System in Indonesia. Although the precomputed scenarios for this purpose qualify for satisfying deliverables, the study of further improvements continues. While TsunAWI is governed by the Shallow Water Equations, an extension of the model is based on a nonhydrostatic approach. At the arrival of a tsunami wave in coastal regions with rough bathymetry, the term containing the nonhydrostatic part of pressure, that is neglected in the original hydrostatic model, gains in importance. In consideration of this term, a better approximation of the wave is expected. Differences of hydrostatic and nonhydrostatic model results are contrasted in the standard benchmark problem of a solitary wave runup on a plane beach. The observation data provided by Titov and Synolakis (1995) serves as reference. The nonhydrostatic approach implies a set of equations that are similar to the Shallow Water Equations, so the variation of the code can be implemented on top. However, this additional routines cause a lot of issues you have to cope with. So far the computations of the model were purely explicit. In the nonhydrostatic version the determination of an additional unknown and the solution of a large sparse system of linear equations is necessary. The latter constitutes the lion's share of computing time and memory requirement. Since the corresponding matrix is only symmetric in structure and not in values, an iterative Krylov Subspace Method is used, in particular the restarted Generalized Minimal Residual Algorithm GMRES(m). With regard to optimization, we present a comparison of several combinations of sequential and parallel preconditioning techniques respective number of iterations and setup/application time. Since the used software package pARMS 3.2, that provides solving and preconditioning techniques, works via MPI parallelism, in an auxiliary branch we adapted TsunAWI and switched from OpenMP to MPI with attached importance to internal partition management.

  10. Numerical aspects in modeling high Deborah number flow and elastic instability

    NASA Astrophysics Data System (ADS)

    Kwon, Youngdon

    2014-05-01

    Investigating highly nonlinear viscoelastic flow in 2D domain, we explore problem as well as property possibly inherent in the streamline upwinding technique (SUPG) and then present various results of elastic instability. The mathematically stable Leonov model written in tensor-logarithmic formulation is employed in the framework of finite element method for spatial discretization of several representative problem domains. For enhancement of computation speed, decoupled integration scheme is applied for shear thinning and Boger-type fluids. From the analysis of 4:1 contraction flow at low and moderate values of the Deborah number (De) the solution with SUPG method does not show noticeable difference from the one by the computation without upwinding. On the other hand, in the flow regime of high De, especially in the state of elastic instability the SUPG significantly distorts the flow field and the result differs considerably from the solution acquired straightforwardly. When the strength of elastic flow and thus the nonlinearity further increase, the computational scheme with upwinding fails to converge and evolutionary solution does not become available any more. All this result suggests that extreme care has to be taken on occasions where upwinding is applied, and one has to first of all prove validity of this algorithm in the case of high nonlinearity. On the contrary, the straightforward computation with no upwinding can efficiently model representative phenomena of elastic instability in such benchmark problems as 4:1 contraction flow, flow over a circular cylinder and flow over asymmetric array of cylinders. Asymmetry of the flow field occurring in the symmetric domain, enhanced spatial and temporal fluctuation of dynamic variables and flow effects caused by extension hardening are properly described in this study.

  11. Methods and numerical aspects of nanoscopic contact area estimation in atomistic tribological simulations

    NASA Astrophysics Data System (ADS)

    Eder, S.; Vernes, A.; Betz, G.

    2014-01-01

    We show how data obtained from molecular dynamics (MD) simulations of nanoscale friction should be treated for producing constitutive system parameters with a proper error estimation. A visualisation scheme for discrete atomistic geometries based on the smooth particle method (SPM) was parametrised and validated to yield an accurate and computationally robust estimation of the contact area between two touching nanoscopic asperities. We present some thoughts on the error estimation of the contact forces occurring due to the load and the shearing motion. The variance in the friction force constitutes the main source of error for the fitting of the constitutive system parameters. The dependence of the constitutive system parameters on the number of available data points was also studied. It was shown that an equal spacing (by load) of the data points can result in better values for the system parameters than the convergence trend suggests.

  12. Aspects of spirituality concerning illness.

    PubMed

    van Leeuwen, René; Tiesinga, Lucas J; Jochemsen, Henk; Jochemasen, Henk; Post, Doeke

    2007-12-01

    The spiritual dimension of illness, health and care may be seen as a unique aspect in addition to the physical, mental and social dimension. This contribution describes experiences of patients, nurses and hospital chaplains in relation to the spiritual aspects of being ill. Qualitative research was performed with the design of a focus group study, consisting of 13 focus groups with a total of 67 participants. A purposive sample was used comprising patients, nurses and hospital chaplains working in oncology, cardiology and neurology in different institutions and regions in the Netherlands. The qualitative analysis consisted of open coding and the determining of topics, followed by the subsequent attachment of substantial dimensions and characteristic fragments. Data were analysed by using the computer program KWALITAN. Spirituality play various roles in patients lives during their illness. There is a wide range of topics that may have an individual effect on patients. Despite differences in emphasis, the topics play a role in different patient categories. Although the spiritual topics seem to manifest themselves more clearly in long-term care relationships, they may also play a role during brief admittance periods (such as treatment decisions). The spiritual topics that arise from this study offer caregivers a framework for signalling the spiritual needs of patients. The question is not whether spirituality is a relevant focus area in care, but how and to what degree it plays a role with individual patients. Follow up research should aim at further exploration of spiritual aspects in care, the relationship between spirituality and health and at effective training of caregivers.

  13. [Psychotherapeutic aspects in forensic evaluation].

    PubMed

    Schorsch, E

    1983-09-01

    Splitting up of psychiatry into a forensic and a psychotherapeutic branch is unjustified as far as the scope of these branches is concerned, and entails a disadvantage at the expense of the delinquents, since nobody feels he is therapeutically responsible. Therapeutic aspects in expertising are worked out, and the specific difficulties and conflicts between forensic and therapeutic problems are demonstrated. Anyone who believes that therapeutic identity cannot be reconciled with legislation concerned with culpability, suffers from the prejudice induced by a "blind spot" in his mental eye.

  14. Medical aspects of scuba diving.

    PubMed

    Suke, R

    1985-11-01

    Scuba divers may encounter dangerous levels of stress, due to increased ambient pressures and hostile environments. Divers therefore require a high level of mental and cardiorespiratory fitness. They must be informed of specific contraindications to diving. Family physicians with a basic knowledge of the medical aspects of scuba diving are in a very good position to examine and advise sports divers. Screening mainly involves an assessment of emotional stability and cardiorespiratory fitness, and an ear, nose and throat examination. Common problems suffered by scuba divers are discussed, as are temporary and permanent contraindications to diving.

  15. Nutritional aspects related to endometriosis.

    PubMed

    Halpern, Gabriela; Schor, Eduardo; Kopelman, Alexander

    2015-01-01

    This literature review analyzed the evidence on nutritional aspects related to the pathogenesis and progression of endometriosis. Diets deficient in nutrients result in changes in lipid metabolism, oxidative stress and promote epigenetic abnormalities, that may be involved in the genesis and progression of the disease. Foods rich in omega 3 with anti-inflammatory effects, supplementation with N-acetylcysteine, vitamin D and resveratrol, in addition to the increased consumption of fruits, vegetables (preferably organic) and whole grains exert a protective effect, reducing the risk of development and possible regression of disease. Dietary re-education seems to be a promising tool in the prevention and treatment of endometriosis. PMID:26841161

  16. Medical Aspects of Scuba Diving

    PubMed Central

    Suke, Ralph

    1985-01-01

    Scuba divers may encounter dangerous levels of stress, due to increased ambient pressures and hostile environments. Divers therefore require a high level of mental and cardiorespiratory fitness. They must be informed of specific contraindications to diving. Family physicians with a basic knowledge of the medical aspects of scuba diving are in a very good position to examine and advise sports divers. Screening mainly involves an assessment of emotional stability and cardiorespiratory fitness, and an ear, nose and throat examination. Common problems suffered by scuba divers are discussed, as are temporary and permanent contraindications to diving. PMID:21274131

  17. Mechanical engineering aspects of TFTR

    SciTech Connect

    Citrolo, J.C.

    1983-04-01

    This paper briefly presents the principles which characterize a tokamak and discusses the mechanical aspects of TFTR, particularly the toroidal field coils and the vacuum chamber, in the context of being key components common to all tokamaks. The mechanical loads on these items as well as other design requirements are considered and the solutions to these requirements as executed in TFTR are presented. Future technological developments beyond the scope of TFTR, which are necessary to bring the tokamak concept to a full fusion-power system, are also presented. Additional methods of plasma heating, current drive, and first wall designs are examples of items in this category.

  18. Psychological aspects of endocrine disease.

    PubMed

    Sonino, N; Guidi, J; Fava, G A

    2015-03-01

    This review illustrates how an innovative psychoneuroendocrine approach to endocrine patients may improve their management. Important psychological issues pertain to all the different phases of an endocrine disorder. Before disease onset, stressful life events may play a pathogenetic role and, together with chronic stress, may contribute to a cumulative burden also called allostatic load; psychological and psychiatric symptoms are common both in the prodromal and in the active phase of illness; after cure or remission, there could be residual symptoms and impaired quality of life that deserve attention. All these aspects should be taken into consideration and introduced in current endocrine care and practice.

  19. Potential and limits of numerical modelling for supporting the development of HTS devices

    NASA Astrophysics Data System (ADS)

    Sirois, Frédéric; Grilli, Francesco

    2015-04-01

    In this paper, we present a general review of the status of numerical modelling applied to the design of high temperature superconductor devices. The importance of this tool is emphasized at the beginning of the paper, followed by formal definitions of the notions of models, numerical methods and numerical models. The state-of-the-art models are listed, and the main limitations of existing numerical models are reported. Those limitations are shown to concern two aspects: on the one hand, the numerical performance (i.e. speed) of the methods themselves is not good enough yet; on the other hand, the availability of model file templates, material data and benchmark problems is clearly insufficient. Paths for improving those elements are indicated in the paper. Besides the technical aspects of the research to be further pursued, for instance in adaptive numerical methods, most recommendations command for an increased collective effort for sharing files, data, codes and their documentation.

  20. Numerical investigation of the Taylor-Couette and Batchelor flows with heat transfer: physics and numerical modelling

    NASA Astrophysics Data System (ADS)

    Kiełczewski, K.; Tuliszka-Sznitko, E.; Bontoux, P.

    2014-08-01

    In the paper the authors present the results obtained during a numerical investigation (Direct Numerical Simulation/Spectral Vanishing Viscosity method - DNS/SVV) of a flow with heat transfer in rotating cavities (i.e. the flow between two concentric disks and two concentric cylinders). These model flows are useful from numerical and experimental point of view among others because of the simplicity of their geometry. Simultaneously, the flows in rotating cavities appear in numerous industrial installations and machines in the field of mechanics and chemistry, e.g., in ventilation installations, desalination tanks and waste water tanks, in cooling system, in gas turbines and axial compressors. In the paper attention is focused on the laminar-turbulent region in the configuration of the large aspect ratio i.e. Taylor-Couette flow (a Batchelor flow case of small aspect ratio Γ = 0.04 is also presented for comparison). The main purpose of computations is to investigate the influence of different parameters (the aspect ratio, the end-wall boundary conditions and temperature gradient) on the flow structure and flow characteristics. For the non-isothermal flow cases the Nusselt number distributions along cylinders are presented and are correlated with the flow structures. The λ2 method has been used for visualization.

  1. Exploring the Educational Benefits of Introducing Aspect-Oriented Programming Into a Programming Course

    ERIC Educational Resources Information Center

    Boticki, I.; Katic, M.; Martin,S.

    2013-01-01

    This paper explores the educational benefits of introducing the aspect-oriented programming paradigm into a programming course in a study on a sample of 75 undergraduate software engineering students. It discusses how using the aspect-oriented paradigm, in addition to the object-oriented programming paradigm, affects students' programs, their…

  2. Numerical simulation of platelet margination in microcirculation

    NASA Astrophysics Data System (ADS)

    Zhao, Hong; Shaqfeh, Eric

    2009-11-01

    The adhesion of platelets to vascular walls is the first step in clotting. This process critically depends on the preferential concentration of platelets near walls. The presence of red blood cells, which are the predominant blood constituents, is known to affect the steady state platelet concentration and the dynamic platelet margination, but the underlying mechanism is not well understood to-day. We use a direct numerical simulation to study the platelet margination process, with particular emphasis on the Stokesian hydrodynamic interactions among red cells, platelets, and vessel walls. Well-known mechanical models are used for the shearing and bending stiffness of red cell membranes, and the stiffer platelets are modeled as rigid discoids. A boundary integral formulation is used to solve the flow field, where the numerical solution procedure is accelerated by a parallel O(N N) smooth particle-mesh Ewald method. The effects of red cell hematocrit and deformability will be discussed.

  3. Terminological aspects of data elements

    SciTech Connect

    Strehlow, R.A. ); Kenworthey, W.H. Jr. ); Schuldt, R.E. )

    1991-01-01

    The creation and display of data comprise a process that involves a sequence of steps requiring both semantic and systems analysis. An essential early step in this process is the choice, definition, and naming of data element concepts and is followed by the specification of other needed data element concept attributes. The attributes and the values of data element concept remain associated with them from their birth as a concept to a generic data element that serves as a template for final application. Terminology is, therefore, centrally important to the entire data creation process. Smooth mapping from natural language to a database is a critical aspect of database, and consequently, it requires terminology standardization from the outset of database work. In this paper the semantic aspects of data elements are analyzed and discussed. Seven kinds of data element concept information are considered and those that require terminological development and standardization are identified. The four terminological components of a data element are the hierarchical type of a concept, functional dependencies, schematas showing conceptual structures, and definition statements. These constitute the conventional role of terminology in database design. 12 refs., 8 figs., 1 tab.

  4. Investigating legal aspects of cyberbullying.

    PubMed

    Paul, Simone; Smith, Peter K; Blumberg, Herbert H

    2012-11-01

    In the UK schools are required by law to protect students from bullying; the responsibility of teachers to govern such behaviour has been extended outside the school setting to include cyberbullying. In this investigation, cyberbullying in secondary education is explored from the student perspective using a qualitative method of enquiry. Reported awareness and understanding about the legal aspects of cyberbullying are investigated; consideration is given to legislation, cybercrime, children's rights, school sanctions and safeguarding responsibilities. A total of 197 male and female students aged between 11 and 14 years old participated. Despite the availability of information on guidelines and legislation at national, local, and school level, this does not appear to have reached ground level of the individual student. There is a considerable gap between what students should know and what they report to be aware of with regard to legal aspects of cyberbullying. To address concerns of keeping up with the pace of change in cyberbullying, a collaborative approach is required with young people and adults sharing expertise.

  5. Investigating legal aspects of cyberbullying.

    PubMed

    Paul, Simone; Smith, Peter K; Blumberg, Herbert H

    2012-11-01

    In the UK schools are required by law to protect students from bullying; the responsibility of teachers to govern such behaviour has been extended outside the school setting to include cyberbullying. In this investigation, cyberbullying in secondary education is explored from the student perspective using a qualitative method of enquiry. Reported awareness and understanding about the legal aspects of cyberbullying are investigated; consideration is given to legislation, cybercrime, children's rights, school sanctions and safeguarding responsibilities. A total of 197 male and female students aged between 11 and 14 years old participated. Despite the availability of information on guidelines and legislation at national, local, and school level, this does not appear to have reached ground level of the individual student. There is a considerable gap between what students should know and what they report to be aware of with regard to legal aspects of cyberbullying. To address concerns of keeping up with the pace of change in cyberbullying, a collaborative approach is required with young people and adults sharing expertise. PMID:23079364

  6. Clustering aspects in nuclear structure functions

    SciTech Connect

    Hirai, M.; Saito, K.; Watanabe, T.; Kumano, S.

    2011-03-15

    For understanding an anomalous nuclear effect experimentally observed for the beryllium-9 nucleus at the Thomas Jefferson National Accelerator Facility, clustering aspects are studied in structure functions of deep inelastic lepton-nucleus scattering by using momentum distributions calculated in antisymmetrized (or fermionic) molecular dynamics (AMD) and also in a simple shell model for comparison. According to AMD, the {sup 9}Be nucleus consists of two {alpha}-like clusters with a surrounding neutron. The clustering produces high-momentum components in nuclear wave functions, which affects nuclear modifications of the structure functions. We investigated whether clustering features could appear in the structure function F{sub 2} of {sup 9}Be along with studies for other light nuclei. We found that nuclear modifications of F{sub 2} are similar in both AMD and shell models within our simple convolution description although there are slight differences in {sup 9}Be. It indicates that the anomalous {sup 9}Be result should be explained by a different mechanism from the nuclear binding and Fermi motion. If nuclear-modification slopes d(F{sub 2}{sup A}/F{sub 2}{sup D})/dx are shown by the maximum local densities, the {sup 9}Be anomaly can be explained by the AMD picture, namely by the clustering structure, whereas it certainly cannot be described in the simple shell model. This fact suggests that the large nuclear modification in {sup 9}Be should be explained by large densities in the clusters. For example, internal nucleon structure could be modified in the high-density clusters. The clustering aspect of nuclear structure functions is an unexplored topic which is interesting for future investigations.

  7. Numerical Study of Tip Vortex Flows

    NASA Technical Reports Server (NTRS)

    Dacles-Mariani, Jennifer; Hafez, Mohamed

    1998-01-01

    This paper presents an overview and summary of the many different research work related to tip vortex flows and wake/trailing vortices as applied to practical engineering problems. As a literature survey paper, it outlines relevant analytical, theoretical, experimental and computational study found in literature. It also discusses in brief some of the fundamental aspects of the physics and its complexities. An appendix is also included. The topics included in this paper are: 1) Analytical Vortices; 2) Experimental Studies; 3) Computational Studies; 4) Wake Vortex Control and Management; 5) Wake Modeling; 6) High-Lift Systems; 7) Issues in Numerical Studies; 8) Instabilities; 9) Related Topics; 10) Visualization Tools for Vertical Flows; 11) Further Work Needed; 12) Acknowledgements; 13) References; and 14) Appendix.

  8. Numerical simulations of the QUELL experiment in SULTAN

    SciTech Connect

    Marinucci, C.

    1995-03-01

    The QUench Experiment on Long Length (QUELL) in the SULTAN Facility is planned to investigate the quench propagation and detection of a conductor with ITER relevant geometry and scaled performance. The objective of this study is to show the ability of QUELL to provide quench conditions relevant for ITER and to simulate the system performance, dealing in particular with the design aspects of the power supply, cryogenic system and heaters. The numerical analysis was performed with GANDALF - a 1-D code to analyze Dual Channel Cable-in-Conduit Conductors. A numerical convergence test and a comparison with another code and with analytical results have confirmed the validity of the simulations.

  9. Numerical and experimental modelling of the radial compressor stage

    NASA Astrophysics Data System (ADS)

    Syka, Tomáš; Matas, Richard; LuÅáček, Ondřej

    2016-06-01

    This article deals with the description of the numerical and experimental model of the new compressor stage designed for process centrifugal compressors. It's the first member of the new stages family developed to achieve the state of the art thermodynamic parameters. This stage (named RTK01) is designed for high flow coefficient with 3D shaped impeller blades. Some interesting findings were gained during its development. The article is focused mainly on some interesting aspects of the development methodology and numerical simulations improvement, not on the specific stage properties. Conditions and experimental equipment, measured results and their comparison with ANSYS CFX and NUMECA FINE/Turbo CFD simulations are described.

  10. Numerical Asymptotic Solutions Of Differential Equations

    NASA Technical Reports Server (NTRS)

    Thurston, Gaylen A.

    1992-01-01

    Numerical algorithms derived and compared with classical analytical methods. In method, expansions replaced with integrals evaluated numerically. Resulting numerical solutions retain linear independence, main advantage of asymptotic solutions.

  11. Aerodynamics of high-lift, low-aspect-ratio unswept wings

    NASA Technical Reports Server (NTRS)

    Katz, Joseph

    1989-01-01

    It is presently demonstrated that highly cambered, low aspect ratio airfoil configurations can be neither experimentally nor numerically developed on the basis of two-dimensional methods; the strong dependency of airfoil shape on aspect ratio requires the definition of a planform to be conducted first, in order to serve as input for three-dimensional optimization methods. It is found that even the simplified three-dimensional computational method presently employed can accelerate a multielement-airfoil wing development.

  12. Nutritional aspect of pediatric inflammatory bowel disease: its clinical importance.

    PubMed

    Kim, Seung; Koh, Hong

    2015-10-01

    Inflammatory bowel disease (IBD) is a chronic inflammatory disease mainly affecting the gastrointestinal tract. The incidence of the disease is rapidly increasing worldwide, and a number of patients are diagnosed during their childhood or adolescence. Aside from controlling the gastrointestinal symptoms, nutritional aspects such as growth, bone mineral density, anemia, micronutrient deficiency, hair loss, and diet should also be closely monitored and managed by the pediatric IBD team especially since the patients are in the development phase.

  13. Nutritional aspect of pediatric inflammatory bowel disease: its clinical importance

    PubMed Central

    Kim, Seung

    2015-01-01

    Inflammatory bowel disease (IBD) is a chronic inflammatory disease mainly affecting the gastrointestinal tract. The incidence of the disease is rapidly increasing worldwide, and a number of patients are diagnosed during their childhood or adolescence. Aside from controlling the gastrointestinal symptoms, nutritional aspects such as growth, bone mineral density, anemia, micronutrient deficiency, hair loss, and diet should also be closely monitored and managed by the pediatric IBD team especially since the patients are in the development phase. PMID:26576179

  14. Ergonomical aspects of anaesthetic practice

    PubMed Central

    Raghavendra Rao, RS

    2016-01-01

    Anaesthesiologist's service begins as a general physician, goes on as an investigator cum data analyser leading to the architectural planning of a forthcoming surgical event, but only after articulately convincing the subject along with his kith and kin. In the era of rapid developments in the field of medicine which includes relevant developments in anaesthetic care, an adequate work environment has to be provided to the anaesthesia team so that all anaesthetic procedures can be carried out safely and efficiently and an optimal workflow can be established in the operating room environment. Such ecological state demands an updated knowledge and ergonomics to aid him. Unfortunately, ergonomics is an area of anaesthesia that has received little attention and should be addressed through more education and training for workplace well-ness. Hence, an attempt is made to discuss few aspects on ergonomics for the interface between anaesthesiologist-machine-patient systems regarded as human-machine-system. PMID:27212716

  15. Epidemiological aspects of heart diseases

    PubMed Central

    Shi, Aimin; Tao, Ziqi; Wei, Peng; Zhao, Jing

    2016-01-01

    Cardiovascular diseases (CVDs) are the leading cause of mortality worldwide. Coronary heart disease (CHD) is the main cause of mortality in heart patients following stroke, rheumatic heart disease and myocardial infarctions. Approximately 80% of individuals succumb to CVDs, due to poor living conditions in low and middle income families and malnutrition. Infectious diseases, human immunodeficiency, tuberculosis, malaria, high blood pressure or hypertension, obesity and overweight, and nutritional disorders including smoking, excessive alcohol consumption, high salt and sugar intake, as well as other factors are responsible for CVDs and CHDs in young as well as elderly individuals. The focus of the present review are recent epidemiological aspects of CVD and CHD as well as the usefulness of a Mediterranean diet for heart patients and the prevention of heart diseases. PMID:27602082

  16. Immune Aspects of Female Infertility

    PubMed Central

    Brazdova, Andrea; Senechal, Helene; Peltre, Gabriel; Poncet, Pascal

    2016-01-01

    Immune infertility, in terms of reproductive failure, has become a serious health issue involving approximately 1 out of 5 couples at reproductive age. Semen that is defined as a complex fluid containing sperm, cellular vesicles and other cells and components, could sensitize the female genital tract. The immune rejection of male semen in the female reproductive tract is explained as the failure of natural tolerance leading to local and/or systemic immune response. Present active immune mechanism may induce high levels of anti-seminal/sperm antibodies. It has already been proven that iso-immunization is associated with infertility. Comprehensive studies with regards to the identification of antibody-targets and the determination of specific antibody class contribute to the development of effective immuno-therapy and, on the other hand, potential immuno-contraception, and then of course to complex patient diagnosis. This review summarizes the aspects of female immune infertility. PMID:27123194

  17. Sensory aspects of movement disorders

    PubMed Central

    Patel, Neepa; Jankovic, Joseph; Hallett, Mark

    2016-01-01

    Movement disorders, which include disorders such as Parkinson’s disease, dystonia, Tourette’s syndrome, restless legs syndrome, and akathisia, have traditionally been considered to be disorders of impaired motor control resulting predominantly from dysfunction of the basal ganglia. This notion has been revised largely because of increasing recognition of associated behavioural, psychiatric, autonomic, and other non-motor symptoms. The sensory aspects of movement disorders include intrinsic sensory abnormalities and the effects of external sensory input on the underlying motor abnormality. The basal ganglia, cerebellum, thalamus, and their connections, coupled with altered sensory input, seem to play a key part in abnormal sensorimotor integration. However, more investigation into the phenomenology and physiological basis of sensory abnormalities, and about the role of the basal ganglia, cerebellum, and related structures in somatosensory processing, and its effect on motor control, is needed. PMID:24331796

  18. [Modern psychosomatic aspects of dermatology].

    PubMed

    Jovanović, M; Duran, V; Poljacki, M; Misić-Pavkov, G; Matović, L; Subotić, M; Golub, R

    1994-01-01

    Concerning their origin most diseases are multifactorial and that goes for skin diseases too. Emphasizing just one must not exclude further research and other aspects of etiopathogenetic mechanisms. It has been known for along time that psychological factors have a certain influence on the start, aggravation and maintenance on skin changes and that cosmetic defects of this kind disturb the psychological peace of the sick person and his capacity of establishing satisfactory social relations. Psychosomatic approach in dermatology cannot be reduced to investigation of specific etiology in the field of psyche without physical or social spheres. It unites all of them and in that way the old question what cause and what the consequence is has no importance, because there is no time or distance limit among them. They act simultaneously, holistically. PMID:7739438

  19. [Clinical aspects of witchcraft delusions].

    PubMed

    Pashkovskiĭ, V E

    2005-01-01

    To distinguish clinical variants and to specify nosologic entity of witchcraft delusions, 69 patients (10 males, aged 15-72 years) have been examined. It was found that witchcraft delusions exist in passive and active forms. In a passive form, the patient is sure that unknown (mystic) power damaged him/her; in an active form the patient, possessing a gift for unusual abilities, can influence the others (bewitches, heals, etc). Five clinical syndromes, in the structure of which the above delusions were found, namely, paranoiac-hypochondriac, hallucination-paranoid, depressive-paranoid, paraphrenic and delirious, were identified. Psychoses of schizophrenia spectrum were diagnosed in 52 patients, organic--in 8, alcoholic--in 7 and recurrent depressive disorder--in 2. Clinical significance of witchcraft delusions is closely related to its social aspect. Being combined with ideas of persecution, poisoning and damage, it results in the brutal forms of delusions defense and may be considered as an unfavorable prognostic trait.

  20. Epidemiological aspects of heart diseases

    PubMed Central

    Shi, Aimin; Tao, Ziqi; Wei, Peng; Zhao, Jing

    2016-01-01

    Cardiovascular diseases (CVDs) are the leading cause of mortality worldwide. Coronary heart disease (CHD) is the main cause of mortality in heart patients following stroke, rheumatic heart disease and myocardial infarctions. Approximately 80% of individuals succumb to CVDs, due to poor living conditions in low and middle income families and malnutrition. Infectious diseases, human immunodeficiency, tuberculosis, malaria, high blood pressure or hypertension, obesity and overweight, and nutritional disorders including smoking, excessive alcohol consumption, high salt and sugar intake, as well as other factors are responsible for CVDs and CHDs in young as well as elderly individuals. The focus of the present review are recent epidemiological aspects of CVD and CHD as well as the usefulness of a Mediterranean diet for heart patients and the prevention of heart diseases.

  1. Ergonomical aspects of anaesthetic practice.

    PubMed

    Raghavendra Rao, R S

    2016-05-01

    Anaesthesiologist's service begins as a general physician, goes on as an investigator cum data analyser leading to the architectural planning of a forthcoming surgical event, but only after articulately convincing the subject along with his kith and kin. In the era of rapid developments in the field of medicine which includes relevant developments in anaesthetic care, an adequate work environment has to be provided to the anaesthesia team so that all anaesthetic procedures can be carried out safely and efficiently and an optimal workflow can be established in the operating room environment. Such ecological state demands an updated knowledge and ergonomics to aid him. Unfortunately, ergonomics is an area of anaesthesia that has received little attention and should be addressed through more education and training for workplace well-ness. Hence, an attempt is made to discuss few aspects on ergonomics for the interface between anaesthesiologist-machine-patient systems regarded as human-machine-system. PMID:27212716

  2. Psychiatric Aspects of Organ Transplantation

    PubMed Central

    Kalra, G.; Desousa, A.

    2011-01-01

    Surgical transplantation of human organs from deceased as well as living donors to sick and dying patients began after the Second World War. Over the past 50 years the transplantation of human organs, tissues and cells has become a worldwide practice which has extended, and greatly enhanced the quality of hundreds of thousands of lives. The field of transplantation medicine provides an important chance for liaison between psychiatric professionals and other transplant physicians and surgeons. The discrepancy between the ever-increasing demand for organs but the decreasing supply makes it important to evaluate and prioritize individuals who are in dire need of the organ. However, this also gives rise to certain ethical questions. The following paper discusses various psychiatric aspects of organ transplantation in general. PMID:25013589

  3. Clinical aspects of cervical insufficiency.

    PubMed

    Lotgering, Frederik K

    2007-06-01

    Fetal loss is a painful experience. A history of second or early third trimester fetal loss, after painless dilatation of the cervix, prolapse or rupture of the membranes, and expulsion of a live fetus despite minimal uterine activity, is characteristic for cervical insufficiency. In such cases the risk of recurrence is high, and a policy of prophylactic cerclage may be safer than one of serial cervical length measurements followed by cerclage, tocolysis and bed rest in case of cervical shortening or dilatation. In low risk cases, however, prophylactic cerclage is not useful. There is a need for more basic knowledge of cervical ripening, objective assessment of cervical visco-elastic properties, and randomized controlled trials of technical aspects of cervical cerclage (e.g. suturing technique).

  4. Key aspects of coronal heating

    NASA Astrophysics Data System (ADS)

    Klimchuk, James A.

    2015-04-01

    We highlight 10 key aspects of coronal heating that must be understood before we can consider the problem to be solved. (1) All coronal heating is impulsive. (2) The details of coronal heating matter. (3) The corona is filled with elemental magnetic stands. (4) The corona is densely populated with current sheets. (5) The strands must reconnect to prevent an infinite build-up of stress. (6) Nanoflares repeat with different frequencies. (7) What is the characteristic magnitude of energy release? (8) What causes the collective behaviour responsible for loops? (9) What are the onset conditions for energy release? (10) Chromospheric nanoflares are not a primary source of coronal plasma. Significant progress in solving the coronal heating problem will require coordination of approaches: observational studies, field-aligned hydrodynamic simulations, large-scale and localized three-dimensional magnetohydrodynamic simulations, and possibly also kinetic simulations. There is a unique value to each of these approaches, and the community must strive to coordinate better.

  5. Key Aspects of Coronal Heating

    NASA Astrophysics Data System (ADS)

    Klimchuk, James A.

    2015-04-01

    We highlight ten key aspects of coronal heating that must be understood before we can consider the problem to be solved. (1) All coronal heating is impulsive. (2) The details of coronal heating matter. (3) The corona is filled with elemental magnetic stands. (4) The corona is densely populated with current sheets. (5) The strands must reconnect to prevent an infinite buildup of stress. (6) Nanoflares repeat with different frequencies. (7) What is the characteristic magnitude of energy release? (8) What causes the collective behavior responsible for loops? (9) What are the onset conditions for energy release? (10) Chromospheric nanoflares are not a primary source of coronal plasma. Significant progress in solving the coronal heating problem will require a coordination of approaches: observational studies, field-aligned hydrodynamic simulations, large-scale and localized 3D MHD simulations, and possibly also kinetic simulations. There is a unique value to each of these approaches, and the community must strive to coordinate better.

  6. Nutritional aspects of stone disease.

    PubMed

    Hess, Bernhard

    2002-12-01

    Kidney stones can form during a state of urinary supersaturation. Because urine often is supersaturated with respect to various salts, crystal formation is very common in nonstone formers and stone formers alike, and it may even be absent in kidney stone formers. Thus, uncomplicated crystalluria does not distinguish between stone formers and healthy people. Landmark clinical studies, however, have shown that under identical conditions of dietary and fluid intake, healthy controls almost exclusively excrete single calcium oxalate crystals 3 to 4 microns in diameter, whereas recurrent calcium stone formers pass larger crystals, 10 to 12 microns in diameter, often fused into polycrystalline aggregates 20 to 300 microns in diameter. Thus, those who form stones appear to be more "sensitive" to a given diet than nonstone formers. It is in these subjects that "bad dietary habits" induce nephrolithiasis, making nutritional aspects important. This article reviews the current evidence-based knowledge of the impact of nutrition on the recurrence of a kidney stone.

  7. The molecular aspects of chordoma.

    PubMed

    Gulluoglu, Sukru; Turksoy, Ozlem; Kuskucu, Aysegul; Ture, Ugur; Bayrak, Omer Faruk

    2016-04-01

    Chordomas are one of the rarest bone tumors, and they originate from remnants of embryonic notochord along the spine, more frequently at the skull base and sacrum. Although they are relatively slow growing and low grade, chordomas are highly recurrent, aggressive, locally invasive, and prone to metastasize to the lungs, bone, and the liver. Chordomas highly and generally show a dual epithelial-mesenchymal differentiation. These tumors resist chemotherapy and radiotherapy; therefore, radical surgery and high-dose radiation are the most used treatments, although there is no standard way to treat the disease. The molecular biology process behind the initiation and progression of a chordoma needs to be revealed for a better understanding of the disease and to develop more effective therapies. Efforts to discover the mysteries of these molecular aspects have delineated several molecular and genetic alterations in this tumor. Here, we review and describe the emerging insights into the molecular landscape of chordomas.

  8. Evolution of cooling-channel properties for varying aspect ratio

    NASA Astrophysics Data System (ADS)

    Pizzarelli, M.; Nasuti, F.; Onofri, M.

    2016-07-01

    A trade-off analysis is performed on a cooling channel system representative of liquid rocket engine cooling systems. This analysis requires multiple cooling channel flow calculations which are performed by means of a proper numerical approach, referred to as quasi-two-dimensional (2D) model. This model, which is suited to high-aspect-ratio cooling channels (HARCC), permits to have a fast prediction of both the coolant flow evolution and the temperature distribution along the whole cooling channel structure. Before using the quasi-2D model for the trade-off analysis, its validation by comparison with computational fluid dynamics (CFD) results is presented and discussed. The results show that the pump power required to overcome losses in the cooling circuit can be minimized selecting a channel shaped with a suitably high aspect ratio.

  9. Taylor vortices in annular spherical flow at large aspect ratios

    NASA Astrophysics Data System (ADS)

    Loukopoulos, Vassilios C.; Karahalios, George T.

    2004-07-01

    Motivated by recent theoretical and experimental work, we numerically investigate spherical Couette flow with a view to obtaining for the first time Taylor vortices at large aspect ratios σ such as 0.38, 0.42, and 0.48. It is found that Taylor vortices can exist, stable or time-dependent, in a range of Reynolds numbers [Re1, Re2] and their formation depends on the aspect ratio, on the imposition of various rotationary conditions on the boundaries, on the history of the flow and on the rate at which energy is transferred into the fluid to its final value. With increasing σ the range [Re1, Re2] manifests a clear tendency to shorten.

  10. Aerodynamic design using numerical optimization

    NASA Technical Reports Server (NTRS)

    Murman, E. M.; Chapman, G. T.

    1983-01-01

    The procedure of using numerical optimization methods coupled with computational fluid dynamic (CFD) codes for the development of an aerodynamic design is examined. Several approaches that replace wind tunnel tests, develop pressure distributions and derive designs, or fulfill preset design criteria are presented. The method of Aerodynamic Design by Numerical Optimization (ADNO) is described and illustrated with examples.

  11. A Vocabulary for Numerical Control.

    ERIC Educational Resources Information Center

    Campbell, Clifton Paul

    This glossary presents a standardized nomenclature for numerical control. It defines and describes some 286 technical words, terms, abbreviations, and acronyms which form a specialized vocabulary. The aim of this glossary is to provide a means for arriving at some common understanding of terminology for numerical control technology. Numerous…

  12. Note on symmetric BCJ numerator

    NASA Astrophysics Data System (ADS)

    Fu, Chih-Hao; Du, Yi-Jian; Feng, Bo

    2014-08-01

    We present an algorithm that leads to BCJ numerators satisfying manifestly the three properties proposed by Broedel and Carrasco in [42]. We explicitly calculate the numerators at 4, 5 and 6-points and show that the relabeling property is generically satisfied.

  13. Numerical simulation of dusty plasmas

    SciTech Connect

    Winske, D.

    1995-09-01

    The numerical simulation of physical processes in dusty plasmas is reviewed, with emphasis on recent results and unresolved issues. Three areas of research are discussed: grain charging, weak dust-plasma interactions, and strong dust-plasma interactions. For each area, we review the basic concepts that are tested by simulations, present some appropriate examples, and examine numerical issues associated with extending present work.

  14. Numerical Optimization of converging diverging miniature cavitating nozzles

    NASA Astrophysics Data System (ADS)

    Chavan, Kanchan; Bhingole, B.; Raut, J.; Pandit, A. B.

    2015-12-01

    The work focuses on the numerical optimization of converging diverging cavitating nozzles through nozzle dimensions and wall shape. The objective is to develop design rules for the geometry of cavitating nozzles for desired end-use. Two main aspects of nozzle design which affects the cavitation have been studied i.e. end dimensions of the geometry (i.e. angle and/or curvature of the inlet, outlet and the throat and the lengths of the converging and diverging sections) and wall curvatures(concave or convex). Angle of convergence at the inlet was found to control the cavity growth whereas angle of divergence of the exit controls the collapse of cavity. CFD simulations were carried out for the straight line converging and diverging sections by varying converging and diverging angles to study its effect on the collapse pressure generated by the cavity. Optimized geometry configurations were obtained on the basis of maximum Cavitational Efficacy Ratio (CER)i.e. cavity collapse pressure generated for a given permanent pressure drop across the system. With increasing capabilities in machining and fabrication, it is possible to exploit the effect of wall curvature to create nozzles with further increase in the CER. Effect of wall curvature has been studied for the straight, concave and convex shapes. Curvature has been varied and effect of concave and convex wall curvatures vis-à-vis straight walls studied for fixed converging and diverging angles.It is concluded that concave converging-diverging nozzles with converging angle of 20° and diverging angle of 5° with the radius of curvature 0.03 m and 0.1530 m respectively gives maximum CER. Preliminary experiments using optimized geometry are indicating similar trends and are currently being carried out. Refinements of the CFD technique using two phase flow simulations are planned.

  15. Representing Cloud Processing of Aerosol in Numerical Models

    SciTech Connect

    Mechem, D.B.; Kogan, Y.L.

    2005-03-18

    The satellite imagery in Figure 1 provides dramatic examples of how aerosol influences the cloud field. Aerosol from ship exhaust can serve as nucleation centers in otherwise cloud-free regions, forming ship tracks (top image), or can enhance the reflectance/albedo in already cloudy regions. This image is a demonstration of the first indirect effect, in which changes in aerosol modulate cloud droplet radius and concentration, which influences albedo. It is thought that, through the effects it has on precipitation (drizzle), aerosol can also affect the structure and persistence of planetary boundary layer (PBL) clouds. Regions of cellular convection, or open pockets of cloudiness (bottom image) are thought to be remnants of strongly drizzling PBL clouds. Pockets of Open Cloudiness (POCs) (Stevens et al. 2005) or Albrecht's ''rifts'' are low cloud fraction regions characterized by anomalously low aerosol concentrations, implying they result from precipitation. These features may in fact be a demonstration of the second indirect effect. To accurately represent these clouds in numerical models, we have to treat the coupled cloud-aerosol system. We present the following series of mesoscale and large eddy simulation (LES) experiments to evaluate the important aspects of treating the coupled cloud-aerosol problem. 1. Drizzling and nondrizzling simulations demonstrate the effect of drizzle on a mesoscale forecast off the California coast. 2. LES experiments with explicit (bin) microphysics gauge the relative importance of the shape of the aerosol spectrum on the 3D dynamics and cloud structure. 3. Idealized mesoscale model simulations evaluate the relative roles of various processes, sources, and sinks.

  16. Numerical Simulation of a Tornado Generating Supercell

    NASA Technical Reports Server (NTRS)

    Proctor, Fred H.; Ahmad, Nashat N.; LimonDuparcmeur, Fanny M.

    2012-01-01

    The development of tornadoes from a tornado generating supercell is investigated with a large eddy simulation weather model. Numerical simulations are initialized with a sounding representing the environment of a tornado producing supercell that affected North Carolina and Virginia during the Spring of 2011. The structure of the simulated storm was very similar to that of a classic supercell, and compared favorably to the storm that affected the vicinity of Raleigh, North Carolina. The presence of mid-level moisture was found to be important in determining whether a supercell would generate tornadoes. The simulations generated multiple tornadoes, including cyclonic-anticyclonic pairs. The structure and the evolution of these tornadoes are examined during their lifecycle.

  17. Biological Aspects of Computer Virology

    NASA Astrophysics Data System (ADS)

    Vlachos, Vasileios; Spinellis, Diomidis; Androutsellis-Theotokis, Stefanos

    Recent malware epidemics proved beyond any doubt that frightful predictions of fast-spreading worms have been well founded. While we can identify and neutralize many types of malicious code, often we are not able to do that in a timely enough manner to suppress its uncontrolled propagation. In this paper we discuss the decisive factors that affect the propagation of a worm and evaluate their effectiveness.

  18. Congenital myotonic dystrophy in Britain. I. Clinical aspects.

    PubMed Central

    Harper, P S

    1975-01-01

    A clinical and genetic study of congenital myotonic dystrophy in Britain has been carried out in 70 patients from 54 sibships. The clinical aspects are analysed here, and the existence of a syndrome clinically distinct from myotonic dystrophy of later onset is confirmed. Characteristic features included neonatal hypotonia, motor and mental retardation, and facial diplegia. A high incidence of talipes occurs at birth together with hydramnios and reduced fetal movements during pregnancy, factors suggesting prenatal onset of the disorder in many cases. Prolonged survival is the rule after infancy, but the occurrence of numerous neonatal deaths in the sibships suggests the existence of unrecognized cases dying in the neonatal period. PMID:1101835

  19. Affective Dynamics in Psychopathology

    PubMed Central

    Trull, Timothy J.; Lane, Sean P.; Koval, Peter; Ebner-Priemer, Ulrich W.

    2016-01-01

    We discuss three varieties of affective dynamics (affective instability, emotional inertia, and emotional differentiation). In each case, we suggest how these affective dynamics should be operationalized and measured in daily life using time-intensive methods, like ecological momentary assessment or ambulatory assessment, and recommend time-sensitive analyses that take into account not only the variability but also the temporal dependency of reports. Studies that explore how these affective dynamics are associated with psychological disorders and symptoms are reviewed, and we emphasize that these affective processes are within a nexus of other components of emotion regulation.

  20. Environmental aspects of arsenic toxicity.

    PubMed

    Peters, G R; McCurdy, R F; Hindmarsh, J T

    1996-01-01

    The toxicity of arsenic and its long history of use in human culture has resulted in widespread concern about the natural and anthropogenic levels of arsenic in our environment. In this article, an overview of the current environmental status of arsenic is presented. A brief history of the usage of this element is followed by a discussion of the current applications. Both natural as well as anthropogenic sources of input are described and discussed in terms of their relative impact on the Earth's environment. Numerous control mechanisms for arsenic exist in the environment, and the major processes involved (physical, chemical, and biological) are highlighted. Natural cycling of this element through the various environmental compartments (air, water, soil, and biota) are described as well as some current methods for the removal of arsenic from natural and industrial waters. Finally, a brief overview of the most common methods for the analysis of arsenic in environmental samples is presented.

  1. Nonperturbative aspects of ABJM theory

    NASA Astrophysics Data System (ADS)

    Drukker, Nadav; Mariño, Marcos; Putrov, Pavel

    2011-11-01

    Using the matrix model which calculates the exact free energy of ABJM theory on {mathbb{S}^3} we study non-perturbative effects in the large N expansion of this model, i.e., in the genus expansion of type IIA string theory on AdS4 × mathbb{C}{mathbb{P}^3} . We propose a general prescription to extract spacetime instanton actions from general matrix models, in terms of period integrals of the spectral curve, and we use it to determine them explicitly in the ABJM matrix model, as exact functions of the 't Hooft coupling. We confirm numerically that these instantons control the asymptotic growth of the genus expansion. Furthermore, we find that the dominant instanton action at strong coupling determined in this way exactly matches the action of an Euclidean D2-brane instanton wrapping mathbb{R}{mathbb{P}^3}.

  2. The Beam Break-Up Numerical Simulator

    SciTech Connect

    Travish, G.A.

    1989-11-01

    Beam Break-Up (BBU) is a severe constraint in accelerator design, limiting beam current and quality. The control of BBU has become the focus of much research in the design of the next generation collider, recirculating and linear induction accelerators and advanced accelerators. Determining the effect on BBU of modifications to cavities, the focusing elements or the beam is frequently beyond the ability of current analytic models. A computer code was written to address this problem. The Beam Break-Up Numerical Simulator (BBUNS) was designed to numerically solve for beam break-up (BBU) due to an arbitrary transverse wakefield. BBUNS was developed to be as user friendly as possible on the Cray computer series. The user is able to control all aspects of input and output by using a single command file. In addition, the wakefield is specified by the user and read in as a table. The program can model energy variations along and within the beam, focusing magnetic field profiles can be specified, and the graphical output can be tailored. In this note we discuss BBUNS, its structure and application. Included are detailed instructions, examples and a sample session of BBUNS. This program is available for distribution. 50 refs., 18 figs., 5 tabs.

  3. Direct Numerical Simulation of Automobile Cavity Tones

    NASA Technical Reports Server (NTRS)

    Kurbatskii, Konstantin; Tam, Christopher K. W.

    2000-01-01

    The Navier Stokes equation is solved computationally by the Dispersion-Relation-Preserving (DRP) scheme for the flow and acoustic fields associated with a laminar boundary layer flow over an automobile door cavity. In this work, the flow Reynolds number is restricted to R(sub delta*) < 3400; the range of Reynolds number for which laminar flow may be maintained. This investigation focuses on two aspects of the problem, namely, the effect of boundary layer thickness on the cavity tone frequency and intensity and the effect of the size of the computation domain on the accuracy of the numerical simulation. It is found that the tone frequency decreases with an increase in boundary layer thickness. When the boundary layer is thicker than a certain critical value, depending on the flow speed, no tone is emitted by the cavity. Computationally, solutions of aeroacoustics problems are known to be sensitive to the size of the computation domain. Numerical experiments indicate that the use of a small domain could result in normal mode type acoustic oscillations in the entire computation domain leading to an increase in tone frequency and intensity. When the computation domain is expanded so that the boundaries are at least one wavelength away from the noise source, the computed tone frequency and intensity are found to be computation domain size independent.

  4. Thermal aspects of grinding for surface integrity

    NASA Astrophysics Data System (ADS)

    Ju, Yongqing

    Thermal aspects of grinding are analyzed in detail since it is argued that temperature controls the effect of grinding on workpiece surface integrity. Transient and steady state heat partition in sliding contact is discussed in detail. This leads to a complete thermal model for heat partition and temperatures in surface grinding. Numerical predictions of the model are shown to agree with experimental results available in the literature. Effects of grinding conditions including real contact area ratio, thermal properties, feeds and speeds, and type of cut (down or up grinding) on heat partition and workpiece temperature are studied systematically. It is shown that the presence of the fluid inside the grinding zone can reduce the heat flux into the workpiece and workpiece temperature significantly. It is also found that some ratios of workpiece velocity to wheel velocity result in high temperatures and therefore should be avoided. This result provides a basis for the difference between conventional and creep-feed grinding regions. After obtaining temperature, an efficient and robust FFT approach is developed to obtain the thermal stress field induced by moving heat sources. Study of the 'hot spot' problem shows that the effect of hot spots on surface displacement and stress is small suggesting that grinding thermal stress is induced by the global temperature while local temperature controls metallurgical phase transformations. It is also shown that thermal stress is dominant on the global scale while the global scale mechanical stress is insignificant. Thus, the superior thermal properties of CBN compared to Alsb2Osb3 leads to low temperature and less deleterious residual stresses. Finally, spectral analysis is performed to evaluate contact behavior of the finished surface. This analysis shows that a good grinding process improves not only the magnitude of the surface roughness but the frequency content as well.

  5. Ricin Toxicity: Clinical and Molecular Aspects

    PubMed Central

    Moshiri, Mohammad; Hamid, Fatemeh; Etemad, Leila

    2016-01-01

    Seeds of the castor bean plant Ricinuscommunis L (CB) contain ricin toxin (RT), one of the most poisonous naturally-occurring substances known. Ricin toxin, a water-soluble glycoprotein that does not partition into the oil extract, is a ribosome-inactivating toxin composed of two chains, labeled A and B. Severity of the toxicity varies depending on the route of exposure to the toxin. Inhalational is the most toxic route, followed by oral ingestion. Orally-ingested RT accumulates in the liver and spleen but other cells are also affected. The main clinical manifestations are also related to the administration route. Oral ingestion of CB or RT results in abdominal pain, vomiting, diarrhea, and various types of gastrointestinal bleeding that leading to volume depletion, hypovolemic shock, and renal failure. Inhalation of the toxin presents with non-cardiogenic pulmonary edema, diffuse necrotizing pneumonia, interstitial and alveolar inflammation, and edema. Local injection of RT induces indurations at the injection site, swelling of regional lymph nodes, hypotension, and death. An enzyme-linked immunosorbent assay (ELISA) has been developed to detect RT in animal tissues and fluids. Ricinine, an alkaloid of CB, can be detected in rat urine within 48 h of RT exposure. Supportive care is the basic treatment and standard biowarfare decontamination protocols are used for RT intoxication. Dexamethasone and difluoromethylornithine might be effective treatments. This review examines the clinical and molecular aspects of ricin toxicity. PMID:27536698

  6. Ricin Toxicity: Clinical and Molecular Aspects.

    PubMed

    Moshiri, Mohammad; Hamid, Fatemeh; Etemad, Leila

    2016-04-01

    Seeds of the castor bean plant Ricinuscommunis L (CB) contain ricin toxin (RT), one of the most poisonous naturally-occurring substances known. Ricin toxin, a water-soluble glycoprotein that does not partition into the oil extract, is a ribosome-inactivating toxin composed of two chains, labeled A and B. Severity of the toxicity varies depending on the route of exposure to the toxin. Inhalational is the most toxic route, followed by oral ingestion. Orally-ingested RT accumulates in the liver and spleen but other cells are also affected. The main clinical manifestations are also related to the administration route. Oral ingestion of CB or RT results in abdominal pain, vomiting, diarrhea, and various types of gastrointestinal bleeding that leading to volume depletion, hypovolemic shock, and renal failure. Inhalation of the toxin presents with non-cardiogenic pulmonary edema, diffuse necrotizing pneumonia, interstitial and alveolar inflammation, and edema. Local injection of RT induces indurations at the injection site, swelling of regional lymph nodes, hypotension, and death. An enzyme-linked immunosorbent assay (ELISA) has been developed to detect RT in animal tissues and fluids. Ricinine, an alkaloid of CB, can be detected in rat urine within 48 h of RT exposure. Supportive care is the basic treatment and standard biowarfare decontamination protocols are used for RT intoxication. Dexamethasone and difluoromethylornithine might be effective treatments. This review examines the clinical and molecular aspects of ricin toxicity. PMID:27536698

  7. An experimental and numerical study of the modifications of mixed-layer structure by inhomogeneous surface fluxes and secondary circulations

    SciTech Connect

    Zhong, S.; Doran, J.C.

    1994-07-01

    The problem of scale interactions in the planetary boundary layer (PBL), i.e., how forcing mechanisms of differing spatial and temporal scales affect the properties of the PBL, has been a subject of considerable interest for some time. One aspect of this problem that has received increasing attention in recent years is the representation, in mesoscale and general circulation models. of the effects of subgrid-scale inhomogeneities in surface properties. Differences in sensible and latent heat fluxes between adjacent areas can result in secondary circulations. modifications to the boundary layer structure, and the transport of heat and moisture from one area to another. Despite their potential included on local PBL properties, such effects can not be resolved by numerical models whose scale is too coarse; thus, suitable parameterizations that account for these phenomena are needed. In this paper the authors present some results of wind and temperature measurements over an area with significant variations in surface fluxes on scales of O(10 km). They then use fine resolution numerical simulations to show how synoptic, topographical, and thermal forcing combine to affect the properties of the PBL in the region. Specifically, they consider the relative importance of topography and land-use differences on the generation of secondary circulations and on the depth of the mixed layer, and they show how these effects are modified by synoptic wind fields. Implications for coarser resolution models are also discussed.

  8. [Clinical aspects of Marfan syndrome].

    PubMed

    Belsing, Tina Zimmermann; Lund, Allan Meldgaard; Søndergaard, Lars; Friis-Hansen, Lennart; Abildstrøm, Steen Zabell

    2011-01-31

    Marfan syndrome (MFS) and MFS-related diseases are inherited connective tissue disorders involving several organ systems. The diagnosis of MFS is difficult as the many symptoms overlap with those of other systemic connective tissue diseases. The phenotype is progressive. Effective surgical therapy and standardized follow-up programs have led to an improved lifespan for the affected individuals. Selective angiotensin II, type 1 (AT1) blockers may improve several manifestations of MFS, but the outcome of clinical trials is presently unknown. This review describes the importance of a coordinated strategy for diagnosis, treatment and follow-up. PMID:21276396

  9. Numerical and Experimental Approaches Toward Understanding Lava Flow Heat Transfer

    NASA Astrophysics Data System (ADS)

    Rumpf, M.; Fagents, S. A.; Hamilton, C.; Crawford, I. A.

    2013-12-01

    We have performed numerical modeling and experimental studies to quantify the heat transfer from a lava flow into an underlying particulate substrate. This project was initially motivated by a desire to understand the transfer of heat from a lava flow into the lunar regolith. Ancient regolith deposits that have been protected by a lava flow may contain ancient solar wind, solar flare, and galactic cosmic ray products that can give insight into the history of our solar system, provided the records were not heated and destroyed by the overlying lava flow. In addition, lava-substrate interaction is an important aspect of lava fluid dynamics that requires consideration in lava emplacement models Our numerical model determines the depth to which the heat pulse will penetrate beneath a lava flow into the underlying substrate. Rigorous treatment of the temperature dependence of lava and substrate thermal conductivity and specific heat capacity, density, and latent heat release are imperative to an accurate model. Experiments were conducted to verify the numerical model. Experimental containers with interior dimensions of 20 x 20 x 25 cm were constructed from 1 inch thick calcium silicate sheeting. For initial experiments, boxes were packed with lunar regolith simulant (GSC-1) to a depth of 15 cm with thermocouples embedded at regular intervals. Basalt collected at Kilauea Volcano, HI, was melted in a gas forge and poured directly onto the simulant. Initial lava temperatures ranged from ~1200 to 1300 °C. The system was allowed to cool while internal temperatures were monitored by a thermocouple array and external temperatures were monitored by a Forward Looking Infrared (FLIR) video camera. Numerical simulations of the experiments elucidate the details of lava latent heat release and constrain the temperature-dependence of the thermal conductivity of the particulate substrate. The temperature-dependence of thermal conductivity of particulate material is not well known

  10. Cosmological aspects of spontaneous baryogenesis

    NASA Astrophysics Data System (ADS)

    De Simone, Andrea; Kobayashi, Takeshi

    2016-08-01

    We investigate cosmological aspects of spontaneous baryogenesis driven by a scalar field, and present general constraints that are independent of the particle physics model. The relevant constraints are obtained by studying the backreaction of the produced baryons on the scalar field, the cosmological expansion history after baryogenesis, and the baryon isocurvature perturbations. We show that cosmological considerations alone provide powerful constraints, especially for the minimal scenario with a quadratic scalar potential. Intriguingly, we find that for a given inflation scale, the other parameters including the reheat temperature, decoupling temperature of the baryon violating interactions, and the mass and decay constant of the scalar are restricted to lie within ranges of at most a few orders of magnitude. We also discuss possible extensions to the minimal setup, and propose two ideas for evading constraints on isocurvature perturbations: one is to suppress the baryon isocurvature with nonquadratic scalar potentials, another is to compensate the baryon isocurvature with cold dark matter isocurvature by making the scalar survive until the present.

  11. Educational aspects of molecular simulation

    NASA Astrophysics Data System (ADS)

    Allen, Michael P.

    This article addresses some aspects of teaching simulation methods to undergraduates and graduate students. Simulation is increasingly a cross-disciplinary activity, which means that the students who need to learn about simulation methods may have widely differing backgrounds. Also, they may have a wide range of views on what constitutes an interesting application of simulation methods. Almost always, a successful simulation course includes an element of practical, hands-on activity: a balance always needs to be struck between treating the simulation software as a 'black box', and becoming bogged down in programming issues. With notebook computers becoming widely available, students often wish to take away the programs to run themselves, and access to raw computer power is not the limiting factor that it once was; on the other hand, the software should be portable and, if possible, free. Examples will be drawn from the author's experience in three different contexts. (1) An annual simulation summer school for graduate students, run by the UK CCP5 organization, in which practical sessions are combined with an intensive programme of lectures describing the methodology. (2) A molecular modelling module, given as part of a doctoral training centre in the Life Sciences at Warwick, for students who might not have a first degree in the physical sciences. (3) An undergraduate module in Physics at Warwick, also taken by students from other disciplines, teaching high performance computing, visualization, and scripting in the context of a physical application such as Monte Carlo simulation.

  12. [Genetic aspects of fertility disorders].

    PubMed

    Wieacker, P

    2013-12-01

    Genetic disorders of fertility can occur at the level of gonadal differentiation or function, germ cell production or function, and the genital ducts. In gonadal dysgenesis, the differentiation of testes or ovaries is impaired. Gonadal dysgenesis can be caused by chromosome aberrations or monogenetic defects in XY or XX gonadal dysgenesis. For the biosynthesis of sexual hormones, a normal development of the gonads and an intact hypothalamic-pituitary-gonadal axis is necessary. Disorders of steroid hormone synthesis are associated with an increased or diminished production of sexual hormones. Clinical and genetic aspects of adrenogenital syndrome are discussed here. Mutations of the androgen receptor cause a spectrum of androgen insensitivity ranging from women with female external genitalia through patients with genital ambiguity to men with infertility. Disturbed spermatogenesis is heterogeneous and can be the result of chromosome aberrations such as Klinefelter syndrome or structural aberrations as translocations and microdeletions of the Y chromosome. Premature ovarian failure is characterized by amenorrhea and hypergonadotropic hypogonadism before 40 years of age. Beside nongenetic factors, premature ovarian failure can be caused by chromosome aberrations or monogenetic defects. Disorders of the genital ducts such as anomalies of the müllerian ducts in females and of the wolffian ducts in males can be associated with sterility or infertility.

  13. Biological aspects of gender disorders.

    PubMed

    Corsello, S M; Di Donna, V; Senes, P; Luotto, V; Ricciato, M P; Paragliola, R M; Pontecorvi, A

    2011-12-01

    The scientific community is very interested in the biological aspects of gender disorders and sexual orientation. There are different levels to define an individual's sex: chromosomal, gonadic, and phenotypic sex. Concerning the psychological sex, men and women are different by virtue of their own gender identity, which means they recognize themselves as belonging to a determinate sex. They are different also as a result of their own role identity, a set of behaviors, tendencies, and cognitive and emotional attitudes, commonly defined as "male" and "female". Transsexuality is a disorder characterized by the development of a gender identity opposed to phenotypic sex, whereas homosexuality is not a disturbance of gender identity but only of sexual attraction, expressing sexual orientation towards people of the same sex. We started from a critical review of literature on genetic and hormonal mechanisms involved in sexual differentiation. We re-examined the neuro-anatomic and functional differences between men and women, with special reference to their role in psychosexual differentiation and to their possible implication in the genesis of homosexuality and identity gender disorders. Homosexuality and transsexuality are conditions without a well defined etiology. Although the influence of educational and environmental factors in humans is undeniable, it seems that organic neurohormonal prenatal and postnatal factors might contribute in a determinant way in the development of these two conditions. This "organicistic neurohormal theory" might find support in the study of particular situations in which the human fetus is exposed to an abnormal hormonal environment in utero.

  14. [Histological aspects of posttraumatic regeneration].

    PubMed

    Truupyl'd Aiu

    1976-02-01

    A number of histological aspects (regeneration capacity, origins of regeneration, means of reparation) are discussed on the example of the reparative regeneration of the adrenal cortex. The adrenal cortex is found to possess high regeneration capacity after a traumatic injury of the organ. Realization of this capacity is dependent on general and local conditions, the character and the volume of the injury and the degree of involvment of cambial zones being of substantial significance. Among these zones are the glomerular zone and the external part of the bundle zone, whose proliferating cells are the source of the reparative regeneration of the cortical substance. The reparation of the functioning mass of the adrenal cortex is performed by the type of regenerative hypertrophy or the reparative regeneration depending on the character of the trauma. After the first type, the division of cells and their differentiation occur within the limits of the available structural elements, after the second type- of the newly formed ones. Both types are evolutionally conditioned and are definitely similar eather to postnatal growth and physiological regeneration (regenerative hypertrophy), or to the embryonic histogenesis of the definitive adrenal cortex (reparative regeneration).

  15. Technical aspects of MR perfusion.

    PubMed

    Sourbron, Steven

    2010-12-01

    The most common methods for measuring perfusion with MRI are arterial spin labelling (ASL), dynamic susceptibility contrast (DSC-MRI), and T(1)-weighted dynamic contrast enhancement (DCE-MRI). This review focuses on the latter approach, which is by far the most common in the body and produces measures of capillary permeability as well. The aim is to present a concise but complete overview of the technical issues involved in DCE-MRI data acquisition and analysis. For details the reader is referred to the references. The presentation of the topic is essentially generic and focuses on technical aspects that are common to all DCE-MRI measurements. For organ-specific problems and illustrations, we refer to the other papers in this issue. In Section 1 "Theory" the basic quantities are defined, and the physical mechanisms are presented that provide a relation between the hemodynamic parameters and the DCE-MRI signal. Section 2 "Data acquisition" discusses the issues involved in the design of an optimal measurement protocol. Section 3 "Data analysis" summarizes the steps that need to be taken to determine the hemodynamic parameters from the measured data. PMID:20363574

  16. Hemodynamic aspects of Alzheimer's disease.

    PubMed

    Nagata, Ken; Sato, Mika; Satoh, Yuichi; Watahiki, Yasuhito; Kondoh, Yasushi; Sugawara, Maki; Box, Georgia; Wright, David; Leung, Sumie; Yuya, Hiromichi; Shimosegawa, Eku

    2002-11-01

    Neuroradiological functional imaging techniques demonstrate the patterns of hypoperfusion and hypometabolism that are thought to be useful in the differential diagnosis of Alzheimer's disease (AD) from other dementing disorders. Besides the distribution patterns of perfusion or energy metabolism, vascular transit time (VTT), vascular reactivity (VR), and oxygen extraction fraction (OEF), which can be measured with positron emission tomography (PET), provide hemodynamic aspects of brain pathophysiology. In order to evaluate the hemodynamic features of AD, PET studies were carried out in 20 patients with probable AD and 20 patients with vascular dementia (VaD). The PET findings were not included in their diagnostic process of AD. Using oxygen-15-labeled compounds, cerebral blood flow (CBF), cerebral metabolic rate of oxygen (CMRO(2)), OEF, cerebral blood volume, and VTT were measured quantitatively during resting state. To evaluate VR, CBF was also measured during CO(2) inhalation. There was a significant increase in OEF in and around the parietotemporal cortices, but both VTT and VR were well preserved in patients with AD. By contrast, VR was markedly depressed and VTT was mildly prolonged in patients with VaD. Thus, from the hemodynamic point of view, the preservation of vascular reserve may be a distinct difference between AD and VaD. Furthermore, this indicates a hemodynamic integrity of the vasculature in the level of arterioles in AD.

  17. Breast Cancer 2012 - New Aspects.

    PubMed

    Kolberg, H-C; Lüftner, D; Lux, M P; Maass, N; Schütz, F; Fasching, P A; Fehm, T; Janni, W; Kümmel, S

    2012-07-01

    Treatment options as well as the characteristics for therapeutic decisions in patients with primary and advanced breast cancer are increasing in number and variety. New targeted therapies in combination with established chemotherapy schemes are broadening the spectrum, however potentially promising combinations do not always achieve a better result. New data from the field of pharmacogenomics point to prognostic and predictive factors that take not only the properties of the tumour but also inherited genetic properties of the patient into consideration. Current therapeutic decision-making is thus based on a combination of classical clinical and modern molecular biomarkers. Also health-economic aspects are more frequently being taken into consideration so that health-economic considerations may also play a part. This review is based on information from the recent annual congresses. The latest of these are the 34th San Antonio Breast Cancer Symposium 2011 and the ASCO Annual Meeting 2012. Among their highlights are the clinically significant results from the CLEOPATRA, BOLERO-2, EMILIA and SWOG S0226 trials on the therapy for metastatic breast cancer as well as further state-of-the-art data on the adjuvant use of bisphosphonates within the framework of the ABCSG-12, ZO-FAST, NSABP-B34 and GAIN trials.

  18. Key aspects of coronal heating.

    PubMed

    Klimchuk, James A

    2015-05-28

    We highlight 10 key aspects of coronal heating that must be understood before we can consider the problem to be solved. (1) All coronal heating is impulsive. (2) The details of coronal heating matter. (3) The corona is filled with elemental magnetic stands. (4) The corona is densely populated with current sheets. (5) The strands must reconnect to prevent an infinite build-up of stress. (6) Nanoflares repeat with different frequencies. (7) What is the characteristic magnitude of energy release? (8) What causes the collective behaviour responsible for loops? (9) What are the onset conditions for energy release? (10) Chromospheric nanoflares are not a primary source of coronal plasma. Significant progress in solving the coronal heating problem will require coordination of approaches: observational studies, field-aligned hydrodynamic simulations, large-scale and localized three-dimensional magnetohydrodynamic simulations, and possibly also kinetic simulations. There is a unique value to each of these approaches, and the community must strive to coordinate better. PMID:25897094

  19. General aspects of metal toxicity.

    PubMed

    Kozlowski, H; Kolkowska, P; Watly, J; Krzywoszynska, K; Potocki, S

    2014-01-01

    This review is focused on the general mechanisms of metal toxicity in humans. The possible and mainly confirmed mechanisms of their action are discussed. The metals are divided into four groups due to their toxic effects. First group comprises of metal ions acting as Fenton reaction catalyst mainly iron and copper. These types of metal ions participate in generation of the reactive oxygen species. Metals such as nickel, cadmium and chromium are considered as carcinogenic agents. Aluminum, lead and tin are involved in neurotoxicity. The representative of the last group is mercury, which may be considered as a generally toxic metal. Fenton reaction is a naturally occurring process producing most active oxygen species, hydroxyl radical: Fe(2+) + He2O2 ↔ Fe(3+) + OH(-) + OH(•) It is able to oxidize most of the biomolecules including DNA, proteins, lipids etc. The effect of toxicity depends on the damage of molecules i.e. production site of the hydroxyl radical. Chromium toxicity depends critically on its oxidation state. The most hazardous seems to be Cr(6+) (chromates) which are one of the strongest inorganic carcinogenic agents. Cr(6+) species act also as oxidative agents damaging among other nucleic acids. Redox inactive Al(3+), Cd(2+) or Hg(2+) may interfere with biology of other metal ions e.g. by occupying metal binding sites in biomolecules. All these aspects will be discussed in the review. PMID:25039781

  20. Psychological aspects of peacekeeping operations

    PubMed Central

    Raju, M. S. V. K.

    2014-01-01

    Peacekeeping operations are but one aspect of the systems of peace that have evolved over the past seven decades in a world that is riven with violence of all kinds. With the end of cold war in the late eighties of the last century we have come to see much intrastate violence, in addition to usual interstate hostilities and war, arising out of religious, political, ethnic and economic differences between people. In the changed scenario peacekeeping operations have become complex politico-military-humanitarian efforts. A soldier, trained for conventional military operations, is obliged to participate in the unconventional operations of waging peace in alien lands often in volatile and violent situations and in the process he stands to get exposed to widely variable demands for adjustment that have the potential to bring to the fore many maladaptive responses. Peacekeeping operations also have the potential to offer opportunities for growth and resilience. India is a major player in peacekeeping activities for well over sixty years all over the world. It is necessary for the commanders and mental health professionals to understand the multifarious factors that impinge on the peacekeeping soldier's mind and the emerging patterns of responses thereof for effective management trained manpower and fulfillment of mission objectives PMID:25788805

  1. Key aspects of coronal heating

    PubMed Central

    Klimchuk, James A.

    2015-01-01

    We highlight 10 key aspects of coronal heating that must be understood before we can consider the problem to be solved. (1) All coronal heating is impulsive. (2) The details of coronal heating matter. (3) The corona is filled with elemental magnetic stands. (4) The corona is densely populated with current sheets. (5) The strands must reconnect to prevent an infinite build-up of stress. (6) Nanoflares repeat with different frequencies. (7) What is the characteristic magnitude of energy release? (8) What causes the collective behaviour responsible for loops? (9) What are the onset conditions for energy release? (10) Chromospheric nanoflares are not a primary source of coronal plasma. Significant progress in solving the coronal heating problem will require coordination of approaches: observational studies, field-aligned hydrodynamic simulations, large-scale and localized three-dimensional magnetohydrodynamic simulations, and possibly also kinetic simulations. There is a unique value to each of these approaches, and the community must strive to coordinate better. PMID:25897094

  2. Metabolic aspects of bacterial persisters

    PubMed Central

    Prax, Marcel; Bertram, Ralph

    2014-01-01

    Persister cells form a multi-drug tolerant subpopulation within an isogenic culture of bacteria that are genetically susceptible to antibiotics. Studies with different Gram negative and Gram positive bacteria have identified a large number of genes associated with the persister state. In contrast, the revelation of persister metabolism has only been addressed recently. We here summarize metabolic aspects of persisters, which includes an overview about the bifunctional role of selected carbohydrates as both triggers for the exit from the drug tolerant state and metabolites which persisters feed on. Also alarmones as indicators for starvation have been shown to influence persister levels via different signaling cascades involving the activation of toxin-antitoxin systems and other regulatory factors. Finally, recent data obtained by 13C-isotopolog profiling demonstrated an active amino acid anabolism in Staphylococcus aureus cultures challenged with high drug concentrations. Understanding the metabolism of persister cells poses challenges but also paves the way for the development of anti-persister compounds. PMID:25374846

  3. Aspects of fluency in writing.

    PubMed

    Uppstad, Per Henning; Solheim, Oddny Judith

    2007-03-01

    The notion of 'fluency' is most often associated with spoken-language phenomena such as stuttering. The present article investigates the relevance of considering fluency in writing. The basic argument for raising this question is empirical-it follows from a focus on difficulties in written and spoken language as manifestations of different problems which should be investigated separately on the basis of their symptoms. Key-logging instruments provide new possibilities for the study of writing. The obvious use of this new technology is to study writing as it unfolds in real time, instead of focusing only on aspects of the end product. A more sophisticated application is to exploit the key-logging instrument in order to test basic assumptions of contemporary theories of spelling. The present study is a dictation task involving words and non-words, intended to investigate spelling in nine-year-old pupils with regard to their mastery of the doubling of consonants in Norwegian. In this study, we report on differences with regard to temporal measures between a group of strong writers and a group of poor ones. On the basis of these pupils' writing behavior, the relevance of the concept of 'fluency' in writing is highlighted. The interpretation of the results questions basic assumptions of the cognitive hypothesis about spelling; the article concludes by hypothesizing a different conception of spelling.

  4. Psychological aspects of peacekeeping operations.

    PubMed

    Raju, M S V K

    2014-01-01

    Peacekeeping operations are but one aspect of the systems of peace that have evolved over the past seven decades in a world that is riven with violence of all kinds. With the end of cold war in the late eighties of the last century we have come to see much intrastate violence, in addition to usual interstate hostilities and war, arising out of religious, political, ethnic and economic differences between people. In the changed scenario peacekeeping operations have become complex politico-military-humanitarian efforts. A soldier, trained for conventional military operations, is obliged to participate in the unconventional operations of waging peace in alien lands often in volatile and violent situations and in the process he stands to get exposed to widely variable demands for adjustment that have the potential to bring to the fore many maladaptive responses. Peacekeeping operations also have the potential to offer opportunities for growth and resilience. India is a major player in peacekeeping activities for well over sixty years all over the world. It is necessary for the commanders and mental health professionals to understand the multifarious factors that impinge on the peacekeeping soldier's mind and the emerging patterns of responses thereof for effective management trained manpower and fulfillment of mission objectives. PMID:25788805

  5. Numerical integration of analytic functions

    NASA Astrophysics Data System (ADS)

    Milovanović, Gradimir V.; Tošić, Dobrilo ð.; Albijanić, Miloljub

    2012-09-01

    A weighted generalized N-point Birkhoff-Young quadrature of interpolatory type for numerical integration of analytic functions is considered. Special cases of such quadratures with respect to the generalized Gegenbauer weight function are derived.

  6. Numerical Simulation of Nix's Rotation

    NASA Video Gallery

    This is a numerical simulation of the orientation of Nix as seen from the center of the Pluto system. It has been sped up so that one orbit of Nix around Pluto takes 2 seconds instead of 25 days. L...

  7. Aspects of the Solar Tachocline

    NASA Technical Reports Server (NTRS)

    Elliott, J. R.

    1997-01-01

    The splitting of the frequencies of p-mode multiplets enables information to be gained about the internal rotation of the sun. Such data have revealed a transition at the base of the convection zone from differential rotation similar to that observed at the surface to almost solid-body rotation in the radiative interior. This transition region, known as the tachocline, has been found to be relatively narrow and centered below the base of the convection zone. In this paper, the evolution of the transition region is investigated numerically. Without a large anisotropic viscosity, the depth to which it would spread in one solar age, under the assumption of a constant prescribed differential rotation at the base of the convection zone, is found to be greater than its extent as inferred from helioseismology. In the second part of the paper a highly anisotropic turbulent viscosity with a large horizontal component, as suggested by Spiegel & Zahn (1992), is assumed. In this case, a steady tachocline is formed in which the advection of angular momentum balances the Reynolds stresses. The horizontal component of turbulent viscosity required to match the thickness of the tachocline to that obtained by helioseismology, is estimated to be 5 x 1O sq cm/s The transport of helium is studied in this case and is found to yield a sound-speed increase similar to that required by helioseismology.

  8. Recent Laboratory and Numerical Trailing Vortex Studies

    NASA Technical Reports Server (NTRS)

    Delisi, Donald P.; Greene, George C.; Robins, Robert E.; Singh, Raminder

    1996-01-01

    Results from two laboratory studies and two numerical studies are presented. In the first laboratory study, measurements of the strength of vortices from a three-dimensional (3-D) model wing are presented. The measurements follow the vortices as they evolve in time from a two-dimensional (2-D) line vortex pair to the development and migration of 3-D vortex rings. It is shown that the resulting vortex rings can contain up to 40 percent of the initial vortex circulation. Thus, the formation of vortex rings may not necessarily signal the end of the wake hazard to following aircraft. In the second laboratory study, we present the results of an experiment which shows how the spanwise drag distribution affects wake-vortex evolution. In this experiment, we modified the spanwise drag distribution on a model wing while keeping the total lift and drag constant. The results show that adding drag on or near the centerline of the wing has a larger effect than adding drag at or near the wingtips. These measurements complement the results of NASA studies in the 1970s. In the first numerical study, results of 3-D numerical calculations are presented which show that the vortex Reynolds number has a significant influence on the evolution and migration of wake vortices. When the Reynolds number is large, 3-D vortex rings evolve from the initially 2-D line vortex pairs. These vortex rings then migrate vertically. When the Reynolds number is lower, the transition of vorticity from 2-D to 3-D is delayed. When the Reynolds number is very low, the vortices never transition to 3-D, and the vertical migration is significantly reduced. It is suggested that this effect may have been important in previous laboratory wake-evolution studies. A second numerical study shows the influence that vertical wind shear can have on trailing vortex evolution.

  9. Numerical Optimization Using Computer Experiments

    NASA Technical Reports Server (NTRS)

    Trosset, Michael W.; Torczon, Virginia

    1997-01-01

    Engineering design optimization often gives rise to problems in which expensive objective functions are minimized by derivative-free methods. We propose a method for solving such problems that synthesizes ideas from the numerical optimization and computer experiment literatures. Our approach relies on kriging known function values to construct a sequence of surrogate models of the objective function that are used to guide a grid search for a minimizer. Results from numerical experiments on a standard test problem are presented.

  10. Electrical Aspects of Impinging Flames

    NASA Astrophysics Data System (ADS)

    Chien, Yu-Chien

    This dissertation examines the use of electric fields as one mechanism for controlling combustion as flames are partially extinguished when impinging on nearby surfaces. Electrical aspects of flames, specifically, the production of chemi-ions in hydrocarbon flames and the use of convective flows driven by these ions, have been investigated in a wide range of applications in prior work but despite this fairly comprehensive effort to study electrical aspects of combustion, relatively little research has focused on electrical phenomena near flame extinguishment, nor for flames near impingement surfaces. Electrical impinging flames have complex properties under global influences of ion-driven winds and flow field disturbances from the impingement surface. Challenges of measurements when an electric field is applied in the system have limited an understanding of changes to the flame behavior and species concentrations caused by the field. This research initially characterizes the ability of high voltage power supplies to respond on sufficiently short time scales to permit real time electrical flame actuation. The study then characterizes the influence of an electric field on the impinging flame shape, ion current and flow field of the thermal plume associated with the flame. The more significant further examinations can be separated into two parts: 1) the potential for using electric fields to control the release of carbon monoxide (CO) from surface-impinging flames, and 2) an investigation of controlling electrically the heat transfer to a plate on which the flame impinges. Carbon monoxide (CO) results from the incomplete oxidation of hydrocarbon fuels and, while CO can be desirable in some syngas processes, it is usually a dangerous emission from forest fires, gas heaters, gas stoves, or furnaces where insufficient oxygen in the core reaction does not fully oxidize the fuel to carbon dioxide and water. Determining how carbon monoxide is released and how heat transfer

  11. Bidirectional Modulation of Numerical Magnitude.

    PubMed

    Arshad, Qadeer; Nigmatullina, Yuliya; Nigmatullin, Ramil; Asavarut, Paladd; Goga, Usman; Khan, Sarah; Sander, Kaija; Siddiqui, Shuaib; Roberts, R E; Cohen Kadosh, Roi; Bronstein, Adolfo M; Malhotra, Paresh A

    2016-05-01

    Numerical cognition is critical for modern life; however, the precise neural mechanisms underpinning numerical magnitude allocation in humans remain obscure. Based upon previous reports demonstrating the close behavioral and neuro-anatomical relationship between number allocation and spatial attention, we hypothesized that these systems would be subject to similar control mechanisms, namely dynamic interhemispheric competition. We employed a physiological paradigm, combining visual and vestibular stimulation, to induce interhemispheric conflict and subsequent unihemispheric inhibition, as confirmed by transcranial direct current stimulation (tDCS). This allowed us to demonstrate the first systematic bidirectional modulation of numerical magnitude toward either higher or lower numbers, independently of either eye movements or spatial attention mediated biases. We incorporated both our findings and those from the most widely accepted theoretical framework for numerical cognition to present a novel unifying computational model that describes how numerical magnitude allocation is subject to dynamic interhemispheric competition. That is, numerical allocation is continually updated in a contextual manner based upon relative magnitude, with the right hemisphere responsible for smaller magnitudes and the left hemisphere for larger magnitudes.

  12. Bidirectional Modulation of Numerical Magnitude.

    PubMed

    Arshad, Qadeer; Nigmatullina, Yuliya; Nigmatullin, Ramil; Asavarut, Paladd; Goga, Usman; Khan, Sarah; Sander, Kaija; Siddiqui, Shuaib; Roberts, R E; Cohen Kadosh, Roi; Bronstein, Adolfo M; Malhotra, Paresh A

    2016-05-01

    Numerical cognition is critical for modern life; however, the precise neural mechanisms underpinning numerical magnitude allocation in humans remain obscure. Based upon previous reports demonstrating the close behavioral and neuro-anatomical relationship between number allocation and spatial attention, we hypothesized that these systems would be subject to similar control mechanisms, namely dynamic interhemispheric competition. We employed a physiological paradigm, combining visual and vestibular stimulation, to induce interhemispheric conflict and subsequent unihemispheric inhibition, as confirmed by transcranial direct current stimulation (tDCS). This allowed us to demonstrate the first systematic bidirectional modulation of numerical magnitude toward either higher or lower numbers, independently of either eye movements or spatial attention mediated biases. We incorporated both our findings and those from the most widely accepted theoretical framework for numerical cognition to present a novel unifying computational model that describes how numerical magnitude allocation is subject to dynamic interhemispheric competition. That is, numerical allocation is continually updated in a contextual manner based upon relative magnitude, with the right hemisphere responsible for smaller magnitudes and the left hemisphere for larger magnitudes. PMID:26879093

  13. Bidirectional Modulation of Numerical Magnitude

    PubMed Central

    Arshad, Qadeer; Nigmatullina, Yuliya; Nigmatullin, Ramil; Asavarut, Paladd; Goga, Usman; Khan, Sarah; Sander, Kaija; Siddiqui, Shuaib; Roberts, R. E.; Cohen Kadosh, Roi; Bronstein, Adolfo M.; Malhotra, Paresh A.

    2016-01-01

    Numerical cognition is critical for modern life; however, the precise neural mechanisms underpinning numerical magnitude allocation in humans remain obscure. Based upon previous reports demonstrating the close behavioral and neuro-anatomical relationship between number allocation and spatial attention, we hypothesized that these systems would be subject to similar control mechanisms, namely dynamic interhemispheric competition. We employed a physiological paradigm, combining visual and vestibular stimulation, to induce interhemispheric conflict and subsequent unihemispheric inhibition, as confirmed by transcranial direct current stimulation (tDCS). This allowed us to demonstrate the first systematic bidirectional modulation of numerical magnitude toward either higher or lower numbers, independently of either eye movements or spatial attention mediated biases. We incorporated both our findings and those from the most widely accepted theoretical framework for numerical cognition to present a novel unifying computational model that describes how numerical magnitude allocation is subject to dynamic interhemispheric competition. That is, numerical allocation is continually updated in a contextual manner based upon relative magnitude, with the right hemisphere responsible for smaller magnitudes and the left hemisphere for larger magnitudes. PMID:26879093

  14. Forensic aspects of alcohol abuse and homicide.

    PubMed

    Palijan, Tija Zarković; Kovacević, Drazen; Radeljak, Sanja; Kovac, Marina; Mustapić, Jelena

    2009-09-01

    Numerous investigations indicate a close link between violent behavior, homicide (murder) and alcohol intoxication. With increased frequency of drinking and the chronic consummation of alcohol, the risk of the fatal outcome or homicide and victimization caused by violence is more likely to occur. Studies conducted on convicted murderers suggested that about half of them were under the heavy influence of alcohol at the time of perpetration of murder. The sample in this survey consisted of 177 male offenders which committed criminal act of murder in Croatia from the year of 1990 until 2007 (capital murder and attempted murder). All were assigned for the forensic psychiatric evaluation by the Criminal Justice System (Court of Law) at the Department of Forensic Psychiatry, Neuropsychiatric Hospital, Popovaca, Croatia. For the purpose of this work the sample is divided in two groups of subjects: 1) offenders which were intoxicated at the time of murder and committed offence on intoxicated victim 2) offenders who were sober and committed offence on sober victims. Groups are compared according to the variables of crime and history of alcohol abuse. On the basis of obtained results we can conclude that there are significant differences in relation to the variables and modalities of criminal offence between two groups of offenders and victims. We could conclude that alcohol intoxication in offenders and victims at the time of murder could strongly affect the modalities of murder.

  15. Sickle cell disease: selected aspects of pathophysiology.

    PubMed

    Alexy, T; Sangkatumvong, S; Connes, P; Pais, E; Tripette, J; Barthelemy, J C; Fisher, T C; Meiselman, H J; Khoo, M C; Coates, T D

    2010-01-01

    Sickle cell disease (SCD), a genetically-determined pathology due to an amino acid substitution (i.e., valine for glutamic acid) on the beta-chain of hemoglobin, is characterized by abnormal blood rheology and periods of painful vascular occlusive crises. Sickle cell trait (SCT) is a typically benign variant in which only one beta chain is affected by the mutation. Although both SCD and SCT have been the subject of numerous studies, information related to neurological function and transfusion therapy is still incomplete: an overview of these areas is presented. An initial section provides pertinent background information on the pathology and clinical significance of these diseases. The roles of three factors in the clinical manifestations of the diseases are then discussed: hypoxia, autonomic nervous system regulation and blood rheology. The possibility of a causal relationship between these three factors and sudden death is also examined. It is concluded that further studies in these specific areas are warranted. It is anticipated that the outcome of such research is likely to provide valuable insights into the pathophysiology of SCD and SCT and will lead to improved clinical management and enhanced quality of life. PMID:20364061

  16. Psychiatric aspects of therapeutic abortion.

    PubMed

    Doane, B K; Quigley, B G

    1981-09-01

    A search of the literature on the psychiatric aspects of abortion revealed poor study design, a lack of clear criteria for decisions for or against abortion, poor definition of psychologic symptoms experienced by patients, absence of control groups in clinical studies, and indecisiveness and uncritical attitudes in writers from various disciplines. A review of the sequelae of therapeutic abortion revealed that although the data are vague, symptoms of depression were reported most frequently, whereas those of psychosis were rare. Positive emotional responses and a favourable attitude toward therapeutic abortion were often reported, although again the statistical bases for these reports were inadequate. There was a lack of evidence that the reported effects were due to having an abortion rather than to other variables.Other areas dealt with inadequately in most of the articles reviewed included analyses of symptoms and of the evidence on the duration of sequelae, descriptions of the criteria for approving abortions, investigation of the psychiatric histories of the patients, presentation of data on the effects of refusing abortion requests, systematic study of a number of epidemiologic factors, and analyses of the circumstances leading to pregnancy in patients having abortions. The evidence was found to be sparse on the effects of supportive relationships, different abortion techniques and the length of gestation on the psychologic status of patients. Little attention was paid to the consequences of psychiatric labelling of patients, or to the effect of having an abortion on factors that may influence future pregnancies.The potential roles of health care professionals appear to deserve more study, and little research seems to have been done to compare the psychologic factors associated with abortion and those associated with live birth. As well, there is little evidence that differences in abortion legislation account for significant differences in the psychologic

  17. Psychiatric aspects of Parkinson's disease

    PubMed Central

    Grover, Sandeep; Somaiya, Mansi; Kumar, Santhosh; Avasthi, Ajit

    2015-01-01

    Parkinson's disease (PD) is essentially characterized by the motor symptoms in the form of resting tremor, rigidity and bradykinesia. However, over the years it has been recognized that motor symptoms are just the “tip of the iceberg” of clinical manifestations of PD. Besides motor symptoms, PD characterized by many non-motor symptoms, which include cognitive decline, psychiatric disturbances (depression, psychosis and impulse control), sleep difficulties, autonomic failures (gastrointestinal, cardiovascular, urinary, thermoregulation) and pain syndrome. This review evaluates the various aspects of psychiatric disorders including cognitive decline and sleep disturbances in patients with PD. The prevalence rate of various psychiatric disorders is high in patients with PD. In terms of risk factors, various demographic, clinical and treatment-related variables have been shown to be associated with higher risk of development of psychiatric morbidity. Evidence also suggests that the presence of psychiatric morbidity is associated with poorer outcome. Randomized controlled trials, evaluating the various pharmacological and non-pharmacological treatments for management of psychiatric morbidity in patients with PD are meager. Available evidence suggests that tricyclic antidepressants like desipramine and nortriptyline are efficacious for management of depression. Among the antipsychotics, clozapine is considered to be the best choice for management of psychosis in patients with PD. Among the various cognitive enhancers, evidence suggest efficacy of rivastigmine in management of dementia in patients with PD. To conclude, this review suggests that psychiatric morbidity is highly prevalent in patients with PD. Hence, a multidisciplinary approach must be followed to improve the overall outcome of PD. Further studies are required to evaluate the efficacy of various other measures for management of psychiatric morbidity in patients with PD. PMID:25552854

  18. New biochemical aspects of sweeteners.

    PubMed

    Mäkinen, K K

    1985-03-01

    It has been customary to explain the dentally beneficial effects of xylitol and certain other polyols in terms of microbiological effects only. The almost complete nonfermentability of xylitol in human dental plaque does contribute to the promising clinical findings that have been obtained both in human and animal trials. The nonfermentability or very low fermentability of xylitol by dental plaque leads to a number of consequential phenomena of possible significance in oral biology. The following are associated with the consumption of xylitol: a decrease in the production of lactic acid; the formation of soluble extracellular polysaccharides which make plaque less adhesive; an increase in the general nitrogen metabolism of dental plaque, this resulting in increased transamination and proteolysis with enhancement of the pool of free amino acids and the possibility of ammonia formation. When these effects are combined with the saliva-stimulating properties of xylitol (common to all sweet carbohydrates), the mechanism of the xylitol effect may be more adequately explained. A number of physicochemical facts have, however, received very little attention. They include the following: xylitol and other polyols strongly protect proteins and enzymes from denaturation; xylitol and other polyols seem to govern the precipitation reactions that occur in saliva or in saturated calcium phosphate solutions. The former reactions may play a role in carbohydrate-induced wound healing and the maintenance of the integrity of the oral defence mechanisms. The latter reactions may manifest themselves in the inhibition of spontaneous precipitation of calcium phosphate; thus these polyols may mimic the function of innate inhibitors, statherin, for example. The total explanation of the xylitol effect may thus comprise aspects that are related both to microbiology and to physical chemistry.

  19. Biotechnology patents and ethical aspects.

    PubMed

    Terragni, F

    1993-01-01

    Should we set any limits on patenting? More specifically, must we set any limits on patenting in the field of biotechnology? There should be general agreement on the exclusion of humans from patentability. The European Parliament voted unanimously on an amendment to the Community Directive regarding patenting stating that the human body and its parts are not patentable as such. Patenting of humans indeed would be against fundamental human rights; against the shared principles of freedom, autonomy, and dignity of each single human being. The same reasons apply to requests to reject the "commercialization of the human body." However, much more difficult is reaching a consensus on what are the parts of humans that should not be marketed--organs, tissues, cells, genes, smaller DNA fragments? Probably there is no consensus on where to draw the line when we deal with parts of the human body. Nevertheless, an ethical component is very strong in raising opposition to patenting human DNA. Whatever our personal view on the issue, we cannot deny that ethical aspects must be considered in granting patents on human DNA. With reference to animals, the fears raised are that the patenting of transgenic animals could amplify the instrumental use (reification) and the neglect of their sentient nonobjectual nature: patenting could motivate, instead, the tendency to consider animals as the standard of things invented and as new consumer products. Moreover, animal patenting increases production and thus brings about the great suffering of animals. In regard to plants, the ethical implications of patenting have more to do with their socioeconomic effects, in particular on Third World countries, than for the organisms involved.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. New Aspects of Plasma Physics

    NASA Astrophysics Data System (ADS)

    Schukla, Padma K.; Stenflo, Lennart; Eliasson, Bengt

    2008-03-01

    Nonlinear collective processes in very dense plasmas / P. K. Shukla, B. Eliasson and D. Shaikh -- Quantum, spin and QED effects in plasmas / G. Brodin and M. Marklund -- Spin quantum plasmas - new aspects of collective dynamics / M. Marklund and G. Brodin -- Revised quantum electrodynamics with fundamental applications / B. Lehnert -- Quantum methodologies in beam, fluid and plasma physics / R. Fedele -- Plasma effects in cold atom physics / J. T. Mendonca ... [et al.] -- General properties of the Rayleigh-Taylor instability in different plasma configurations: the plasma foil model / F. Pegoraro and S. V. Bulanov -- The Rayleigh-Taylor instability of a plasma foil accelerated by the radiation pressure of an ultra intense laser pulse / F. Pegoraro and S. V. Bulanov -- Generation of galactic seed magnetic fields / H. Saleem -- Nonlinear dynamics of mirror waves in non-Maxwellian plasmas / O. A. Pokhotelov et al. -- Formation of mirror structures near instability threshold / E. A. Kuznetsov, T. Passot and P. L. Sulem -- Nonlinear dispersive Alfvén waves in magnetoplasmas / P. K. Shukla ... [et al.] -- Properties of drift and Alfvén waves in collisional plasmas / J. Vranjes, S. Poedts and B. P. Pandey -- Current driven acoustic perturbations in partially ionized collisional plasmas / J. Vranjes ... [et al.] -- Multifluid theory of solitons / F. Verheest -- Nonlinear wavepackets in pair-ion and electron-positron-ion plasmas / I. Kourakis et al. -- Electro-acoustic solitary waves in dusty plasmas / A. A. Mamun and P. K. Shukla -- Physics of dust in magnetic fusion devices / Z. Wang et al. -- Short wavelength ballooning mode in Tokamaks / A. Hirose and N. Joiner -- Effects of perpendicular shear superposition and hybrid ions intruduction on parallel shear driven plasma instabilities / T. Kaneko and R. Hatakeyama.

  1. Regulatory aspects of clinical xenotransplantation.

    PubMed

    Schuurman, Henk-Jan

    2015-11-01

    Xenotransplantation attracted interest from regulatory authorities, particularly after the demonstration of pig-to-human transmission of porcine endogenous retrovirus (1996). This added to the risk of a product, resulting in a Guidance of the US Food and Drug Administration (2003). This addresses the full flow chart in product manufacturing, starting with the designated pathogen-free status of the source animal; and special aspects regarding the recipient like informed consent and monitoring for infectious pathogens. Also archiving of records from the donor and recipient, as well as storage of samples is described. The European Medicines Agency issued a Guideline on xenogeneic cell therapy products (2009). Cell-based medicinal products are subject to specific regulations and directives, which apply also to xenogeneic products: the xenotransplant guidances/guidelines are an addition to these regulations. Noteworthy, acellular products like heart valves and decellularized cornea are not considered a cell therapy product, but rather a medical device with its own regulation. WHO issued relevant documents, especially about safety, and the International Xenotransplantation Association published consensus documents, a.o., addressing preclinical efficacy requirements before entering clinical trials. This manuscript presents an overview of the regulatory framework, with special focus on cell therapy products necause these are expected to reach the market first (i.e., pancreatic islets, hepatocytes and cellularized cornea); major illustrations are from the European situation. Albeit being complex, the regulation of xenotransplant products does not form a block in product development, but rather supports the introduction of efficacious and safe products to meet the medical need.

  2. Comparative aspects of rodent and nonrodent animal models for mechanistic and translational diabetes research.

    PubMed

    Renner, Simone; Dobenecker, Britta; Blutke, Andreas; Zöls, Susanne; Wanke, Rüdiger; Ritzmann, Mathias; Wolf, Eckhard

    2016-07-01

    The prevalence of diabetes mellitus, which currently affects 387 million people worldwide, is permanently rising in both adults and adolescents. Despite numerous treatment options, diabetes mellitus is a progressive disease with severe comorbidities, such as nephropathy, neuropathy, and retinopathy, as well as cardiovascular disease. Therefore, animal models predictive of the efficacy and safety of novel compounds in humans are of great value to address the unmet need for improved therapeutics. Although rodent models provide important mechanistic insights, their predictive value for therapeutic outcomes in humans is limited. In recent years, the pig has gained importance for biomedical research because of its close similarity to human anatomy, physiology, size, and, in contrast to non-human primates, better ethical acceptance. In this review, anatomic, biochemical, physiological, and morphologic aspects relevant to diabetes research will be compared between different animal species, that is, mouse, rat, rabbit, pig, and non-human primates. The value of the pig as a model organism for diabetes research will be highlighted, and (dis)advantages of the currently available approaches for the generation of pig models exhibiting characteristics of metabolic syndrome or type 2 diabetes mellitus will be discussed. PMID:27180329

  3. A model for roll stall and the inherent stability modes of low aspect ratio wings at low Reynolds numbers

    NASA Astrophysics Data System (ADS)

    Shields, Matt

    The development of Micro Aerial Vehicles has been hindered by the poor understanding of the aerodynamic loading and stability and control properties of the low Reynolds number regime in which the inherent low aspect ratio (LAR) wings operate. This thesis experimentally evaluates the static and damping aerodynamic stability derivatives to provide a complete aerodynamic model for canonical flat plate wings of aspect ratios near unity at Reynolds numbers under 1 x 105. This permits the complete functionality of the aerodynamic forces and moments to be expressed and the equations of motion to solved, thereby identifying the inherent stability properties of the wing. This provides a basis for characterizing the stability of full vehicles. The influence of the tip vortices during sideslip perturbations is found to induce a loading condition referred to as roll stall, a significant roll moment created by the spanwise induced velocity asymmetry related to the displacement of the vortex cores relative to the wing. Roll stall is manifested by a linearly increasing roll moment with low to moderate angles of attack and a subsequent stall event similar to a lift polar; this behavior is not experienced by conventional (high aspect ratio) wings. The resulting large magnitude of the roll stability derivative, Cl,beta and lack of roll damping, Cl ,rho, create significant modal responses of the lateral state variables; a linear model used to evaluate these modes is shown to accurately reflect the solution obtained by numerically integrating the nonlinear equations. An unstable Dutch roll mode dominates the behavior of the wing for small perturbations from equilibrium, and in the presence of angle of attack oscillations a previously unconsidered coupled mode, referred to as roll resonance, is seen develop and drive the bank angle? away from equilibrium. Roll resonance requires a linear time variant (LTV) model to capture the behavior of the bank angle, which is attributed to the

  4. General aspects of colorectal cancer.

    PubMed

    Centelles, Josep J

    2012-01-01

    Colorectal cancer (CRC) is one of the main causes of death. Cancer is initiated by several DNA damages, affecting proto-oncogenes, tumour suppressor genes, and DNA repairing genes. The molecular origins of CRC are chromosome instability (CIN), microsatellite instability (MSI), and CpG island methylator phenotype (CIMP). A brief description of types of CRC cancer is presented, including sporadic CRC, hereditary nonpolyposis colorectal cancer (HNPCC) or Lynch syndromes, familiar adenomatous polyposis (FAP), MYH-associated polyposis (MAP), Peutz-Jeghers syndrome (PJS), and juvenile polyposis syndrome (JPS). Some signalling systems for CRC are also described, including Wnt-β-catenin pathway, tyrosine kinase receptors pathway, TGF-β pathway, and Hedgehog pathway. Finally, this paper describes also some CRC treatments.

  5. Evolutionary aspects of anxiety disorders

    PubMed Central

    Price, John S.

    2003-01-01

    Danger and harm are avoided by strategic decisions made at all three levels of the triune forebrain: rational (neomammalian), emotional (paleomammalian), and instinctive (reptilian). This applies also to potential harm from conspecifics, which leads to a choice between escalating and de-escalating strategies. Anxiety is a component of de-escalating strategies mediated by the paleomammalian and reptilian forebrains. When the neomammalian (rational) brain fails to deal with the threat of conspecific danger, these more primitive de-escalating strategies may be activated and may present as anxiety disorders. The capacity for concealment of anxiety and other forms of negative affect has also evolved, and excessive concealment may lead to psychopaihology by breaking the negative feedback loop of excessive motivation, leading to impaired performance, leading to signals of distress, and leading to reduced exhortation to succeed on the part of parents and teachers; this situation is illustrated by a model based on the Yerkes-Dodson law. PMID:22033473

  6. Affectional Patterns of Adolescents.

    ERIC Educational Resources Information Center

    O'Donnell, William J.

    1979-01-01

    This study sought to determine if there is a shift with age in affection (1) from parents to friends, (2) from one parent to the other, and (3) from same-sex to opposite-sex friends. Subjects, eighth graders and eleventh graders, completed the Measurement of Family Affective Structure. (Author)

  7. Affective Involvement Instrument.

    ERIC Educational Resources Information Center

    Lemlech, Johanna K.

    1970-01-01

    The Affective Involvement Instrument (AII) describes and classifies affective involvement in the process of decision-making as it occurs during classroom activities such as role-playing or group discussions. The thirty-celled instrument behaviorizes the six processes involved in decision-making and combines them with the taxonomic levels of the…

  8. Static friction, differential algebraic systems and numerical stability

    NASA Astrophysics Data System (ADS)

    Chen, Jian; Schinner, Alexander; Matuttis, Hans-Georg

    We show how Differential Algebraic Systems (Ordinary Differential Equations with algebraic constraints) in mechanics are affected by stability issues and we implement Lubich's projection method to reduce the error to practically zero. Then, we explain how the "numerically exact" implementation for static friction by Differential Algebraic Systems can be stabilized. We conclude by comparing the corresponding steps in the "Contact mechanics" introduced by Moreau.

  9. The Effects of Physical Manipulatives on Children's Numerical Strategies

    ERIC Educational Resources Information Center

    Manches, Andrew; O'Malley, Claire

    2016-01-01

    This article focuses on how the representational properties of manipulatives affect the strategies children employ in problem solving. Two studies examined the effect of physical materials on 4-7-year-old children's problem solving strategies in a numerical (i.e., additive composition) task. The first study showed how children not only identified…

  10. Local structure of numerically generated worm hole spacetime.

    NASA Astrophysics Data System (ADS)

    Siino, M.

    The author investigates the evolution of the apparent horizons in a numerically gererated worm hole spacetime. The behavior of the apparent horizons is affected by the dynamics of the matter field. By using the local mass of the system, he interprets the evolution of the worm hole structure.

  11. Linguistic-Numeric Presentation Mode Effects on Risky Option Preferences

    PubMed

    Dusenbury; Fennema

    1996-11-01

    In this study, we examine preferences between lotteries with chances presented either numerically or linguistically. Presentation mode is predicted to affect preferences due to the perception of linguistic chance as skewed distributions of risk. Based upon weighting functions incorporating risk/uncertainty aversion from ambiguity theory and cumulative prospect theory, we predict that presentation mode effects on risky choices will be detectable in very small risks and in large risks. In two experiments, subjects chose between both gain and loss lotteries with constant payoffs and equivalent numeric and linguistic chances. Presentation mode affected choices when chances were above 50%, where lotteries with numeric chances were more frequently preferred in gains while lotteries with linguistic chances were more often preferred in losses. The effect of presentation mode for low-chance lotteries (5% and less) also affected choices such that numeric choices were generally preferred more frequently in losses and linguistically expressed choices were generally preferred more often in gains. Overall, these results suggest that theories of the effects of second order uncertainty on risky choice may be used to model decisions involving linguistic risk. They also suggest that the study of the perception of linguistic risk assessments can provide insight into the cognitive processing behind the weighting functions proposed to depict decision under risk and uncertainty. Finally, the results have practical implications since information providers can affect decision makers' choices by controlling presentation mode in such a way as to alter the relative attractiveness of uncertain events.

  12. Exploring New Dimensions of Mathematics-Related Affect: Embodied and Social Theories

    ERIC Educational Resources Information Center

    Hannula, Markku S.

    2012-01-01

    This paper will review theoretical approaches for research on mathematics-related affect from the 1990s until today. In order to organise this field, a metatheory of the affective domain is developed, based on distinctions along three dimensions: 1) cognitive, motivational and emotional aspects of affect; 2) rapidly changing affective states…

  13. Incorporating Knowledge of Legal and Ethical Aspects into Computing Curricula of South African Universities

    ERIC Educational Resources Information Center

    Wayman, Ian; Kyobe, Michael

    2012-01-01

    As students in computing disciplines are introduced to modern information technologies, numerous unethical practices also escalate. With the increase in stringent legislations on use of IT, users of technology could easily be held liable for violation of this legislation. There is however lack of understanding of social aspects of computing, and…

  14. Working session 5: Operational aspects and risk analysis

    SciTech Connect

    Cizelj, L.; Donoghue, J.

    1997-02-01

    A general observation is that both operational aspects and risk analysis cannot be adequately discussed without information presented in other sessions. Some overlap of conclusions and recommendations is therefore to be expected. Further, it was assumed that recommendations concerning improvements in some related topics were generated by other sessions and are not repeated here. These include: (1) Knowledge on degradation mechanisms (initiation, progression, and failure). (2) Modeling of degradation (initiation, progression, and failure). (3) Capabilities of NDE methods. (4) Preventive maintenance and repair. One should note here, however, that all of these directly affect both operational and risk aspects of affected plants. A list of conclusions and recommendations is based on available presentations and discussions addressing risk and operational experience. The authors aimed at reaching as broad a consensus as possible. It should be noted here that there is no strict delineation between operational and safety aspects of degradation of steam generator tubes. This is caused by different risk perceptions in different countries/societies. The conclusions and recommendations were divided into four broad groups: human reliability; leakage monitoring; risk impact; and consequence assessment.

  15. The technical aspects of computers.

    PubMed

    Richards, B

    1990-12-01

    This chapter is concerned with the technical aspects of computers. It is therefore concerned with how computers came about in the way they did, and who were the people who pioneered their development--what they were like in the early years, what they are like now, and what are likely to be the future developments. The emphasis is always on giving information to the readers so that they may know what questions to ask of the experts and, equally important, which experts to spend time with. In consequence of this last statement it becomes necessary to present a panorama showing the range of computers both size-wise and cost-wise; such scenario will therefore cover the vista from large main-frames (which must inevitably be needed in District Health Authorities and District General Hospitals) to the desk-top personal computers which all clinicians of the future will find essential. Because readers will be experiencing the impact and, hopefully, the benefits of the computer at the lower end of the size and price scale, considerable space has been devoted to explaining the various items (disc drives, monitors, printers) that pervade the microcomputer scene. New terminology must be introduced to readers if they are to discuss intelligently their computer needs to the providers of such facilities. Just as an automobile is no use without oil, petrol, water and a competent user, so the computer hardware needs computer software and a competent user. The chapter therefore continued with some considerable space being devoted to software (operating systems, programming languages, utilities and expert systems) so that the user will have clear guidance as to which path to follow in order to become a competent user of the present and future technology. Because of the rapid advances in data storage, in networking and in computer programs, the clinicians of tomorrow will have vast sources of information at their disposal. This latter will include not only patient records, but also

  16. Effect of particle aspect ratio in magnetorheology

    NASA Astrophysics Data System (ADS)

    Morillas, Jose R.; Carreón-González, Elizabeth; de Vicente, Juan

    2015-12-01

    We investigate the influence of the aspect ratio of the dispersed particles in magnetorheology. Two systems are studied: conventional magnetorheological fluids prepared by dispersion of nickel nanowires, and inverse ferrofluids prepared by dispersion of glass fibers in a ferrofluid. In both cases the apparent yield stress is found to increase with aspect ratio in contradiction to available models in the literature. Experimental observations demonstrate that the particle volume fraction within the aggregates initially increases with increasing the aspect ratio of the dispersed particles. When the aspect ratio is further raised, a gel-like percolating structure forms inhibiting the formation of elongated clusters in the field direction.

  17. Systemic lupus erythematosus: Clinical and experimental aspects

    SciTech Connect

    Smolen, J.S.

    1987-01-01

    This text covers questions related to the history, etiology, pathogenesis, clinical aspects and therapy of systematic lupus erythematosus (SLE). Both animal models and human SLE are considered. With regard to basic science, concise information on cellular immunology, autoantibodies, viral aspects and molecular biology in SLE is provided. Clinical topics then deal with medical, dermatologic, neurologic, radiologic, pathologic, and therapeutic aspects. The book not only presents the most recent information on clinical and experimental insights, but also looks at future aspects related to the diagnosis and therapy of SLE.

  18. Numerical and experimental approaches to study soil transport and clogging in granular filters

    NASA Astrophysics Data System (ADS)

    Kanarska, Y.; Smith, J. J.; Ezzedine, S. M.; Lomov, I.; Glascoe, L. G.

    2012-12-01

    the soil transport in granular filters we investigated sensitivity of particle clogging mechanisms to various aspects such as particle size ration, the amplitude of hydraulic gradient, particle concentration and contact properties. By averaging the results derived from the grain-scale simulations, we investigated how those factors affect the semi-empirical multiphase model parameters in the large-scale simulation tool. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. The Department of Homeland Security Science and Technology Directorate provided funding for this research.

  19. Numerical Modelling of the Mining Induced Horizontal Displacement

    NASA Astrophysics Data System (ADS)

    Tajduś, Krzysztof

    2015-12-01

    The paper presents results of numerical calculations and modeling of mining-induced surface deformation based on Finite Element Method (FEM). Applying the numerical method discussed to calculations allows us to assume a larger number of factors, such as rock mass structure, fracture network, rock properties, etc., which essentially affect the results obtained. On the basis of an elastic transversely isotropic model, an analysis of horizontal displacement distribution and surface subsidence was carried out for two sample regions of mines. The results of numerical calculations were later compared with the measured values. Such an analysis proved that the applied numerical model properly described distribution and values of subsidence and slope of subsidence trough, though there were serious differences in the values of calculated horizontal displacement, especially in areas of far influence range. In order to improve the matching, the influence of boundary conditions of the model on the value of calculated horizontal displacement was analyzed. The results are presented in graphs.

  20. [Disease and contraception. Recent aspects].

    PubMed

    Rozenbaum, H

    1985-01-01

    copper IUDs do not have the bactericidal power formerly attributed to them. Numerous in vitro studies and statistical comparisons of the effect of spermicides in vivo have demonstrated that local methods provide protection against sexually transmitted diseases. OCs may favor vaginal infection, but some recent studies have indicated that they offer protection against pelvic infections. The protective effect of the condom against sexually transmitted diseases is well known. It has been estimated that, relative to non-users of OCs, each 100,000 users will have 235 fewer cases of benign breast disease, 35 fewer of ovarian cysts, 320 fewer of iron deficiency anemia, 600 fewer of pelivc infection, 117 fewer of extrauterine pregnancy, 32 fewer of rheumatoid arthritis, 1 fewer of endometrial cancer, and 3 fewer of ovarian cancer.

  1. [Affect and mimetic behavior].

    PubMed

    Zepf, S; Ullrich, B; Hartmann, S

    1998-05-01

    The relationship between facial expression and experienced affect presents many problems. The two diametrically opposed positions proposing solutions to this problem are exemplified using the conceptions of Mandler u. Izard. The underlying premises of both conceptions still prevail in various forms. The authors reject the concepts according to which facial expression is merely correlated to the affects (see Mandler 1975) as well as the view that facial expression controls the affects (see Izard 1977). The relationship between affect and facial expression is reexamined, subjecting it to a semiotic, essentially semantic analysis similar to the Ogden and Richards' language and meaning approach. This analysis involves a critical discussion of Scherer's attempt of a purely communicational interpretation using Bühler's organon model. In the author's approach, facial expression is seen not simply as a system of signals, but as a system of representative signs which signify the affects and refer to the emotive meaning of things for the subject. The authors develop the thesis that human beings are not born simply with the ability to speak, but also with the abstract possibility of performing facial expressions. This ability develops by way of coordinating patterns of expressions, which are presumably phylogenetically determined, with affects that take on a socially determined individual form, similar to language acquisition during socialisation. The authors discuss the methodological implications arising for studies investigating the affective meaning of facial expressions. PMID:9632951

  2. [Immunogenetic aspects of autism. Review].

    PubMed

    Pardo-Govea, Tatiana; Solís-Añez, Ernesto

    2009-09-01

    Autism is a generalized or pervasive developmental disorder that affects about five in ten thousand children worldwide (5/10.000). In Maracaibo the incidence is 1.1/1000, with a ratio of male/female, 4:1. The autistic disorder is defined entirely based on the impairment in three areas: 1) Impairment of social interaction, 2) Impairment in communication and 3) Stereotyped and repetitive behavior. Autism is a disorder with a large genetic component and a oligogenic inheritance model has been proposed. Quantitative and qualitative disturbances of certain components of the immune system in patients with autism have been used as endophenotype, one of the strategies used to identify candidate genes for susceptibility to autism. On the other hand the hypersensitivity to specific groups of foods such as casein and gluten has become clear, which has led to the postulation of immunogenetics theories in autism, which mainly involve genes of the histocompatibility major complex. Although it has not been confirmed that immunogenetics factors could be involved in the etiopathogenesis of autism, several studies have shown the influence of the complex Human Leucocyte Antigen (HLA) HLA DR4, DR13, DR11, A2 and others genes in the clinical status, risk and therapeutic response of some psychiatric disorders. The lack of literature demands a greater number of studies related to different ethnic groups and the participation of HLA, as well as the importance of this complex in the pathogenesis of psychiatric illness. PMID:19961061

  3. [Down syndrome--2. Orofacial aspects].

    PubMed

    Reuland-Bosma, W

    1995-01-01

    Because of the higher life expectancy and the ambulant care facilities, the general dentist will be more and more confronted with patients suffering from Down's syndrome. Of major importance are the associated heart and vascular diseases and hypothyroidism, accentuating even more the retarded growth. These patients also show a decrease in resistance, which frequently (50%) results into periodontal disease. Apart from the typical bone "growth" changes, the hypotonicity of the masticatory musculature and the tongue are key factors determining the typical expression. The eruption time and, to a lesser extent, the age of the final teeth is slowed down. When in addition hypothyroidism is observed, this results in a typical radiographic image of the mandible (apices against bottom corticalis). When merely considering the microdontics, the agenesis and the more favourable composition of saliva, caries should be less frequent. However, for techno-hygienic reasons this is often not the case. When the gingiva is affected by a rapidly progressing periodontal disease, it should be frequently cleaned, supported by a chemical plaque treatment. The author emphasizes that on no account prevention can be left to the patient. The patients always need to be helped. Finally the logopaedic purpose of the Castillo-Moralis palatal plate, as well as the functional use of the surgical tongue reduction, are discussed.

  4. Numeral Incorporation in Japanese Sign Language

    ERIC Educational Resources Information Center

    Ktejik, Mish

    2013-01-01

    This article explores the morphological process of numeral incorporation in Japanese Sign Language. Numeral incorporation is defined and the available research on numeral incorporation in signed language is discussed. The numeral signs in Japanese Sign Language are then introduced and followed by an explanation of the numeral morphemes which are…

  5. Genus Paracoccidioides: Species Recognition and Biogeographic Aspects

    PubMed Central

    Theodoro, Raquel Cordeiro; Teixeira, Marcus de Melo; Felipe, Maria Sueli Soares; Paduan, Karina dos Santos; Ribolla, Paulo Martins; San-Blas, Gioconda; Bagagli, Eduardo

    2012-01-01

    Background Paracoccidioidomycosis is a systemic mycosis caused by Paracoccidioides brasiliensis (species S1, PS2, PS3), and Paracoccidioides lutzii. This work aimed to differentiate species within the genus Paracoccidioides, without applying multilocus sequencing, as well as to obtain knowledge of the possible speciation processes. Methodology/Principal Findings Single nucleotide polymorphism analysis on GP43, ARF and PRP8 intein genes successfully distinguished isolates into four different species. Morphological evaluation indicated that elongated conidia were observed exclusively in P. lutzii isolates, while all other species (S1, PS2 and PS3) were indistinguishable. To evaluate the biogeographic events that led to the current geographic distribution of Paracoccidioides species and their sister species, Nested Clade and Likelihood Analysis of Geographic Range Evolution (LAGRANGE) analyses were applied. The radiation of Paracoccidioides started in northwest South America, around 11–32 million years ago, as calculated on the basis of ARF substitution rate, in the BEAST program. Vicariance was responsible for the divergence among S1, PS2 and P. lutzii and a recent dispersal generated the PS3 species, restricted to Colombia. Taking into account the ancestral areas revealed by the LAGRANGE analysis and the major geographic distribution of L. loboi in the Amazon basin, a region strongly affected by the Andes uplift and marine incursions in the Cenozoic era, we also speculate about the effect of these geological events on the vicariance between Paracoccidioides and L. loboi. Conclusions/Significance The use of at least 3 SNPs, but not morphological criteria, as markers allows us to distinguish among the four cryptic species of the genus Paracoccidioides. The work also presents a biogeographic study speculating on how these species might have diverged in South America, thus contributing to elucidating evolutionary aspects of the genus Paracoccidioides. PMID:22666382

  6. Subjective Aspects of Cognitive Control at Different Stages of Processing

    PubMed Central

    Morsella, Ezequiel; Wilson, Lilian E.; Berger, Christopher C.; Honhongva, Mikaela; Gazzaley, Adam; Bargh, John A.

    2009-01-01

    While research on cognitive control has addressed the effects that different forms of cognitive interference have on behavior and the activities of certain brain regions, until recently scientific approaches have been silent regarding the effects of interference on subjective experience. We demonstrate that, at the level of the individual trial, participants can reliably introspect the subjective aspects (e.g., perceptions of difficulty, competition, and control) of responding in interference paradigms. Similar subjective effects were obtained for both expressed and unexpressed (subvocalized) actions. Few participants discerned the source of these effects. These basic findings illuminate aspects of cognitive control and cognitive effort. In addition, these data have implications for the study of response interference in affect and self-control, and they begin to address theories regarding the function of consciousness. PMID:19933564

  7. Numerical Package in Computer Supported Numeric Analysis Teaching

    ERIC Educational Resources Information Center

    Tezer, Murat

    2007-01-01

    At universities in the faculties of Engineering, Sciences, Business and Economics together with higher education in Computing, it is stated that because of the difficulty, calculators and computers can be used in Numerical Analysis (NA). In this study, the learning computer supported NA will be discussed together with important usage of the…

  8. Double-diffusive convection in narrow-aspect cylinders -- experimental data and CFD simulations

    NASA Astrophysics Data System (ADS)

    Webb, Stephen; Dimitrova, Reneta; Pol, Suhas; Fernando, H. J. S.

    2009-11-01

    An experimental and numerical investigation has been conducted on the evolution of double-diffusive convection in a narrow-aspect cylinder in the diffusive regime in which the cylinder is subjected to bottom and side-wall heating. The laboratory experiments included filling of a narrow aspect ratio tank with linearly stratified salt-water solution. This fluid of known stratification was heated from the side and the bottom to form multiple mixed layers of fluid separated by diffusive interfaces. A micro conductivity and temperature probe was used to obtain the measurements of salinity and temperature and to discern the location of the interfaces. These results are compared to the case of bottom heating only. The numerical simulations have been performed with the FLUENT computational fluid dynamics (CFD) code. Laminar and turbulent simulations have been conducted for one of the experiments. Comparison of laboratory and numerical results shows reasonable agreement.

  9. Novel animal models of affective disorders.

    PubMed

    Redei, E E; Ahmadiyeh, N; Baum, A E; Sasso, D A; Slone, J L; Solberg, L C; Will, C C; Volenec, A

    2001-01-01

    Is there an appropriate animal model for human affective disorders? The traditional difficulties in accepting animal models for psychopathology stem from the argument that there is no evidence for concluding that what occurs in the brain of the animal is equivalent to what occurs in the brain of a human. However, if one models any or some core aspects of affective disorder, this model can become an invaluable tool in the analysis of the multitude of causes, genetic, environmental, or pharmacological, that can bring about symptoms homologous to those of patients with affective disorders. Animal models can also allow the study of the mechanisms of specific behaviors, their pathophysiology, and can aid in developing and predicting therapeutic responses to pharmacologic agents. Although animals exhibit complex and varied social and emotional behaviors for which well-validated and standardized measures exist, an understanding that a precise replica of human affective disorders cannot be expected in a single animal model is crucial. Instead, a good animal model of a human disorder should fulfill as many of the four main criteria as possible: (1) strong behavioral similarities, (2) common cause, (3) similar pathophysiology, and (4) common treatment. An animal model fulfilling any or most of these criteria can be used to elucidate the mechanisms of the specific aspect of the model that is homologous to the human disorder. A wide range of animal models of affective disorders, primarily depression, has been developed to date. They include models in which "depressive behavior" is the result of genetic selection or manipulation, environmental stressors during development or in adulthood, or pharmacologic treatments. The assessment of these animal models is based either on behavioral tests measuring traits that are homologous to symptoms of the human disorder they model, or behavioral tests responsive to appropriate pharmacologic treatments. The goal of this review is to focus

  10. Behavioural aspects of patients with Autism Spectrum Disorders (ASD) that affect their dental management

    PubMed Central

    Limeres-Posse, Jacobo; Castaño-Novoa, Patricia; Abeleira-Pazos, Maite; Ramos-Barbosa, Isabel

    2014-01-01

    Dental treatment in patients with Autism Spectrum Disorders (ASD) can be complicated due to the presence of behavioral alterations. In this group, there are no specific behavioral profiles that allow dentist to anticipate the attitude that a patient will show during a visit. Thus, behavioral attitudes have been described that vary from total permissiveness and collaboration during even bloody procedures, to the absolute impossibility in conducting a simple oral examination. There is no effective behavioral management technique for all ASD patients. Prior information, such as the type of ASD or the presence of certain concurrent pathologies can help predict the patient’s likely behavior. Therefore, gathering all the information in a preliminary interview with the parents/guardians of the patient is recommended. Knowing these factors will allow individualized behavioral management strategies to be designed and facilitates the planning of dental treatment. Key words:Dentistry, autism, ASD, behavior management. PMID:24608219

  11. Identifying Aspects of Parental Involvement that Affect the Academic Achievement of High School Students

    ERIC Educational Resources Information Center

    Roulette-McIntyre, Ovella; Bagaka's, Joshua G.; Drake, Daniel D.

    2005-01-01

    This study identified parental practices that relate positively to high school students' academic performance. Parents of 643 high school students participated in the study. Data analysis, using a multiple linear regression model, shows parent-school connection, student gender, and race are significant predictors of student academic performance.…

  12. How Temporal and Spatial Aspects of Presenting Visualizations Affect Learning about Locomotion Patterns

    ERIC Educational Resources Information Center

    Imhof, Birgit; Scheiter, Katharina; Edelmann, Jorg; Gerjets, Peter

    2012-01-01

    Two studies investigated the effectiveness of dynamic and static visualizations for a perceptual learning task (locomotion pattern classification). In Study 1, seventy-five students viewed either dynamic, static-sequential, or static-simultaneous visualizations. For tasks of intermediate difficulty, dynamic visualizations led to better…

  13. Reproductive physiology in Zebu cattle. Unique reproductive aspects that affect their performance.

    PubMed

    Galina, C S; Orihuela, A; Duchateau, A

    1987-11-01

    This article describes the reproductive physiology of Zebu cattle and specific strategies that, when used in concert with an understanding of the physiologic differences between Zebu and other cattle, can improve reproductive performance. PMID:3319088

  14. Measuring One Aspect of Teachers' Affective States: Development of the Science Teachers' Pedagogical Discontentment Scale

    ERIC Educational Resources Information Center

    Southerland, Sherry A.; Nadelson, Louis; Sowell, Scot; Saka, Yavuz; Kahveci, Murat; Granger, Ellen M.

    2012-01-01

    The aim of this research is to describe the development of the Science Teachers' Pedagogical Discontentment Scale, an instrument that measures the discontentment that arises in teachers as they recognize a mismatch between their own pedagogical beliefs and goals and their actual classroom practices. From a conceptual change perspective, we explore…

  15. High Rayleigh number convection numerical experiments

    NASA Astrophysics Data System (ADS)

    Verzicco, Roberto

    2002-03-01

    Numerical experiments on the flow developing in a cylindrical cell of aspect ratio Γ = 1/2 heated from below and cooled from above, are conducted for Rayleigh numbers (Ra) ranging from 2 x 10^6 up to 2 x 10^11. The aim of the present study is to numerically replicate the experiments by Roche et al. (2001) and Niemela et al. (2000) performed using gaseous helium close to the critical point as working fluid (Pr = 0.7). The numerical simulation permitted us to generate a large data base which was validated by the experimental results and, on the other hand, provided physical insights which are missed by the experimental approaches usually limited to pointwise temperature and global heat exchange measurements. Attention is focussed on the presence of large-scale structures whose characterization is important owing to the introduction of constant `winds' sweeping the plates and generating viscous and thermal boundary layers. The analysis of instantaneous snapshots clearly indicates that the topology of the recirculating large scale structures is quite different with respect to what is commonly observed in Γ = 1 cells where a unique large scale recirculation structure completely fills the fluid volume (e.g. Verzicco & Camussi, 1999). It is shown that a transition occurs at about Ra = 10^9; at lower Ra the flow is characterized by the presence of two counter-rotating toroidal rings attached to the horizontal plates. At larger Ra, in contrast, the most intense structure consists of two counter-rotating rolls of unitary aspect ratio. The two types of flow, which co-exists in the range 10^9 < Ra < 10^10, determine different properties of both the thermal and the viscous boundary layers. Indeed, even if the limited range of Ra analyzed in the present simulation does not allow the presence of a transition to be clearly observed in the Nu vs Ra diagram, the proposed scenario is confirmed by the direct analysis of the boundary layer thicknesses and of the kinetic energy and

  16. Numerical integration of subtraction terms

    NASA Astrophysics Data System (ADS)

    Seth, Satyajit; Weinzierl, Stefan

    2016-06-01

    Numerical approaches to higher-order calculations often employ subtraction terms, both for the real emission and the virtual corrections. These subtraction terms have to be added back. In this paper we show that at NLO the real subtraction terms, the virtual subtraction terms, the integral representations of the field renormalization constants and—in the case of initial-state partons—the integral representation for the collinear counterterm can be grouped together to give finite integrals, which can be evaluated numerically. This is useful for an extension towards next-to-next-to-leading order.

  17. Numerical Modelling of Gelating Aerosols

    SciTech Connect

    Babovsky, Hans

    2008-09-01

    The numerical simulation of the gel phase transition of an aerosol system is an interesting and demanding task. Here, we follow an approach first discussed in [6, 8] which turns out as a useful numerical tool. We investigate several improvements and generalizations. In the center of interest are coagulation diffusion systems, where the aerosol dynamics is supplemented with diffusive spreading in physical space. This leads to a variety of scenarios (depending on the coagulation kernel and the diffusion model) for the spatial evolution of the gelation area.

  18. Compounds affecting cholesterol absorption

    NASA Technical Reports Server (NTRS)

    Hua, Duy H. (Inventor); Koo, Sung I. (Inventor); Noh, Sang K. (Inventor)

    2004-01-01

    A class of novel compounds is described for use in affecting lymphatic absorption of cholesterol. Compounds of particular interest are defined by Formula I: ##STR1## or a pharmaceutically acceptable salt thereof.

  19. Key Aspects of Providing Healthcare Services in Disaster Response Stage

    PubMed Central

    POURHOSSEINI, Samira Sadat; ARDALAN, Ali; MEHROLHASSANI, Mohammad Hossien

    2015-01-01

    Abstract Background Health care management in disasters is one of the main parts of disaster management. Health in disasters is affected by performance of various sectors, and has an interactive impact on various aspects of disaster management. The aim of this study was to identify the most important themes affecting the healthcare management in disaster. Method In this qualitative study with a content analysis approach, in-depth interviews in two steps with 30 disaster experts and managers were conducted to collect the data. Results Eleven themes affecting healthcare management in disasters were identified. These themes were related to human resources management, resources management, victims’ management transfer, environmental hygiene monitoring, nutrition management, mental health control, inter-agency coordination, training, technology management, information and communication management, and budget management. Conclusion Providing effective health care service in disasters requires a comprehensive look at the various aspects of disaster management. Effective factors on the success of healthcare in disaster are not limited to the scope of healthcare. There should be a close relationship and interaction between different sectors of disaster management. PMID:26060782

  20. Gravity as an emergent phenomenon: Conceptual aspects

    NASA Astrophysics Data System (ADS)

    Padmanabhan, T.

    2012-07-01

    I describe several conceptual aspects involved in a particular approach which treats gravity as an emergent phenomenon. These aspects are related to the features of classical gravitational theorieswhich defy explanationwithin the conventional perspective. The alternative paradigm throws light on these features and could provide better insights into possible description of quantum structure of spacetime.

  1. [Legal aspects of psychiatry in Soviet legislation].

    PubMed

    Babayan, E A

    1977-01-01

    The Author examines and describes in detail the normative and organizational aspects of forensic-psychiatric services in the URSS. Both criminal expert opinions and civil aspects are described. The problem of civil rights of mentally ill persons are discussed together with education and training of the experts employed in institutions and by the courts.

  2. Some medical aspects of radionuclide intakes

    SciTech Connect

    Poda, G A

    1983-01-01

    In the field of medicine, particularly industrial medicine, the radiation aspect of the practice probably takes about 1/10 of 1% of our time. All the health physicist's tools of principles of internal dosimetry, lung models, mathematics, chemistry, etc. have little meaning until applied to an individual who has had an intake. This article discusses some of the medical aspects of internal dosimetry.

  3. Numerical modelling of river morphodynamics: Latest developments and remaining challenges

    NASA Astrophysics Data System (ADS)

    Siviglia, Annunziato; Crosato, Alessandra

    2016-07-01

    Numerical morphodynamic models provide scientific frameworks for advancing our understanding of river systems. The research on involved topics is an important and socially relevant undertaking regarding our environment. Nowadays numerical models are used for different purposes, from answering questions about basic morphodynamic research to managing complex river engineering problems. Due to increasing computer power and the development of advanced numerical techniques, morphodynamic models are now more and more used to predict the bed patterns evolution to a broad spectrum of spatial and temporal scales. The development and the success of application of such models are based upon a wide range of disciplines from applied mathematics for the numerical solution of the equations to geomorphology for the physical interpretation of the results. In this light we organized this special issue (SI) soliciting multidisciplinary contributions which encompass any aspect needed for the development and applications of such models. Most of the papers in the SI stem from contributions to session HS9.5/GM7.11 on numerical modelling and experiments in river morphodynamics at the European Geosciences Union (EGU) General Assembly held in Vienna, April 27th to May 2nd 2014.

  4. Numerical Modeling of Large-Scale Rocky Coastline Evolution

    NASA Astrophysics Data System (ADS)

    Limber, P.; Murray, A. B.; Littlewood, R.; Valvo, L.

    2008-12-01

    Seventy-five percent of the world's ocean coastline is rocky. On large scales (i.e. greater than a kilometer), many intertwined processes drive rocky coastline evolution, including coastal erosion and sediment transport, tectonics, antecedent topography, and variations in sea cliff lithology. In areas such as California, an additional aspect of rocky coastline evolution involves submarine canyons that cut across the continental shelf and extend into the nearshore zone. These types of canyons intercept alongshore sediment transport and flush sand to abyssal depths during periodic turbidity currents, thereby delineating coastal sediment transport pathways and affecting shoreline evolution over large spatial and time scales. How tectonic, sediment transport, and canyon processes interact with inherited topographic and lithologic settings to shape rocky coastlines remains an unanswered, and largely unexplored, question. We will present numerical model results of rocky coastline evolution that starts with an immature fractal coastline. The initial shape is modified by headland erosion, wave-driven alongshore sediment transport, and submarine canyon placement. Our previous model results have shown that, as expected, an initial sediment-free irregularly shaped rocky coastline with homogeneous lithology will undergo smoothing in response to wave attack; headlands erode and mobile sediment is swept into bays, forming isolated pocket beaches. As this diffusive process continues, pocket beaches coalesce, and a continuous sediment transport pathway results. However, when a randomly placed submarine canyon is introduced to the system as a sediment sink, the end results are wholly different: sediment cover is reduced, which in turn increases weathering and erosion rates and causes the entire shoreline to move landward more rapidly. The canyon's alongshore position also affects coastline morphology. When placed offshore of a headland, the submarine canyon captures local sediment

  5. Comparing numerical and analytic approximate gravitational waveforms

    NASA Astrophysics Data System (ADS)

    Afshari, Nousha; Lovelace, Geoffrey; SXS Collaboration

    2016-03-01

    A direct observation of gravitational waves will test Einstein's theory of general relativity under the most extreme conditions. The Laser Interferometer Gravitational-Wave Observatory, or LIGO, began searching for gravitational waves in September 2015 with three times the sensitivity of initial LIGO. To help Advanced LIGO detect as many gravitational waves as possible, a major research effort is underway to accurately predict the expected waves. In this poster, I will explore how the gravitational waveform produced by a long binary-black-hole inspiral, merger, and ringdown is affected by how fast the larger black hole spins. In particular, I will present results from simulations of merging black holes, completed using the Spectral Einstein Code (black-holes.org/SpEC.html), including some new, long simulations designed to mimic black hole-neutron star mergers. I will present comparisons of the numerical waveforms with analytic approximations.

  6. Conditional Convergence of Numerical Series

    ERIC Educational Resources Information Center

    Gomez, E.; Plaza, A.

    2002-01-01

    One of the most astonishing properties when studying numerical series is that the sum is not commutative, that is the sum may change when the order of its elements is altered. In this note an example is given of such a series. A well-known mathematical proof is given and a MATLAB[C] program used for different rearrangements of the series…

  7. Numerical calculations of flow fields

    NASA Technical Reports Server (NTRS)

    Anderson, D.; Vogel, J. M.

    1973-01-01

    Numerical calculations were made of flow fields generated by various aerodynamic configurations. Data cover flow fields generated by a finitely thick lifting three dimensional wing with subsonic tips moving at supersonic speeds, cross flow instability associated with lifting delta wing configurations such as space shuttles, and flow fields produced by a lifting elliptic cone. Finite difference techniques were used to determine elliptic cone flow.

  8. The Origin of Roman Numerals

    ERIC Educational Resources Information Center

    Dapre, P. A.

    1977-01-01

    A theory on the origin of Roman numerals proposes that the principal numbers can be stylized in terms of a square. It is speculated that the abacus or its equivalents, such as the counter or chequer-board, was used to count before the alphabet became common. (SW)

  9. Metrics for Numerical Control Operators.

    ERIC Educational Resources Information Center

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of students preparing to be numerical control operators, this instructional package is one of eight for the manufacturing occupations cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational…

  10. Numerical Studies of Doped Iron Pnictides

    NASA Astrophysics Data System (ADS)

    Bishop, Christopher; Liang, Shuhua; Moreo, Adriana; Dagotto, Elbio

    The phase diagram of electron-doped pnictides is studied varying the temperature, electronic density, and isotropic disorder strength and dilution via numerical studies of a three-orbital spin-fermion model with lattice degrees of freedom. Doping introduces disorder but in theoretical studies the effect of the randomly located dopants is difficult to address. Numerically the effects of electronic doping, regulated by a chemical potential, and impurity disorder at randomly selected sites can be independently controlled. It was found that the reduction with doping of the Neel and the structural transition temperatures, and the stabilization of a nematic state, is mainly controlled by the magnetic dilution due to the disorder. Fermi surface changes due to doping affect only slightly both critical temperatures. Our findings are compatible with neutron scattering and STM results, unveiling a patchy network of locally magnetically ordered anisotropic clusters, despite the isotropic disorder. The fragile tendency to nematicity intrinsic of translational invariant electronic systems needs to be supplemented by disorder and dilution to stabilize the robust nematic phase experimentally found in electron-doped 122 pnictides. National Science Foundation Grant No. DMR-1404375.

  11. Flow visualization study in high aspect ratio cooling channels for rocket engines

    NASA Astrophysics Data System (ADS)

    Meyer, Michael L.; Giuliani, James E.

    1993-11-01

    geometry. The fluid dynamic and conjugate heat transfer problem of high aspect ratio rocket engine coolant channels are being investigated numerically, but these efforts have been hampered by a lack of validating data. Wall temperature data is available for the conjugate problem for channels without curvature and aspect ratio = 5.0, and unheated fluid dynamic data are available for square and circular cross section channels with curvature at Reynold's numbers up to 40,000. But the effects of aspect ratio on secondary flow development have not been experimentally studied. To provide some insight into the effects of channel aspect ratio on secondary flow and to qualitatively provide anchoring for the numerical codes, a flow visualization experiment was initiated at the NASA Lewis Research Center.

  12. Flow visualization study in high aspect ratio cooling channels for rocket engines

    NASA Technical Reports Server (NTRS)

    Meyer, Michael L.; Giuliani, James E.

    1993-01-01

    geometry. The fluid dynamic and conjugate heat transfer problem of high aspect ratio rocket engine coolant channels are being investigated numerically, but these efforts have been hampered by a lack of validating data. Wall temperature data is available for the conjugate problem for channels without curvature and aspect ratio = 5.0, and unheated fluid dynamic data are available for square and circular cross section channels with curvature at Reynold's numbers up to 40,000. But the effects of aspect ratio on secondary flow development have not been experimentally studied. To provide some insight into the effects of channel aspect ratio on secondary flow and to qualitatively provide anchoring for the numerical codes, a flow visualization experiment was initiated at the NASA Lewis Research Center.

  13. Large eddy simulation of a high aspect ratio combustor

    NASA Astrophysics Data System (ADS)

    Kirtas, Mehmet

    The present research investigates the details of mixture preparation and combustion in a two-stroke, small-scale research engine with a numerical methodology based on large eddy simulation (LES) technique. A major motivation to study such small-scale engines is their potential use in applications requiring portable power sources with high power density. The investigated research engine has a rectangular planform with a thickness very close to quenching limits of typical hydrocarbon fuels. As such, the combustor has a high aspect ratio (defined as the ratio of surface area to volume) that makes it different than the conventional engines which typically have small aspect ratios to avoid intense heat losses from the combustor in the bulk flame propagation period. In most other aspects, this engine involves all the main characteristics of traditional reciprocating engines. A previous experimental work has identified some major design problems and demonstrated the feasibility of cyclic combustion in the high aspect ratio combustor. Because of the difficulty of carrying out experimental studies in such small devices, resolving all flow structures and completely characterizing the flame propagation have been an enormously challenging task. The numerical methodology developed in this work attempts to complement these previous studies by providing a complete evolution of flow variables. Results of the present study demonstrated strengths of the proposed methodology in revealing physical processes occuring in a typical operation of the high aspect ratio combustor. For example, in the scavenging phase, the dominant flow structure is a tumble vortex that forms due to the high velocity reactant jet (premixed) interacting with the walls of the combustor. Since the scavenging phase is a long process (about three quarters of the whole cycle), the impact of the vortex is substantial on mixture preparation for the next combustion phase. LES gives the complete evolution of this flow

  14. Affective responses to dance.

    PubMed

    Christensen, Julia F; Pollick, Frank E; Lambrechts, Anna; Gomila, Antoni

    2016-07-01

    The objective of the present work was the characterization of mechanisms by which affective experiences are elicited in observers when watching dance movements. A total of 203 dance stimuli from a normed stimuli library were used in a series of independent experiments. The following measures were obtained: (i) subjective measures of 97 dance-naïve participants' affective responses (Likert scale ratings, interviews); and (ii) objective measures of the physical parameters of the stimuli (motion energy, luminance), and of the movements represented in the stimuli (roundedness, impressiveness). Results showed that (i) participants' ratings of felt and perceived affect differed, (ii) felt and perceived valence but not arousal ratings correlated with physical parameters of the stimuli (motion energy and luminance), (iii) roundedness in posture shape was related to the experience of more positive emotion than edgy shapes (1 of 3 assessed rounded shapes showed a clear effect on positiveness ratings while a second reached trend level significance), (iv) more impressive movements resulted in more positive affective responses, (v) dance triggered affective experiences through the imagery and autobiographical memories it elicited in some people, and (vi) the physical parameters of the video stimuli correlated only weakly and negatively with the aesthetics ratings of beauty, liking and interest. The novelty of the present approach was twofold; (i) the assessment of multiple affect-inducing mechanisms, and (ii) the use of one single normed stimulus set. The results from this approach lend support to both previous and present findings. Results are discussed with regards to current literature in the field of empirical aesthetics and affective neuroscience.

  15. Affective responses to dance.

    PubMed

    Christensen, Julia F; Pollick, Frank E; Lambrechts, Anna; Gomila, Antoni

    2016-07-01

    The objective of the present work was the characterization of mechanisms by which affective experiences are elicited in observers when watching dance movements. A total of 203 dance stimuli from a normed stimuli library were used in a series of independent experiments. The following measures were obtained: (i) subjective measures of 97 dance-naïve participants' affective responses (Likert scale ratings, interviews); and (ii) objective measures of the physical parameters of the stimuli (motion energy, luminance), and of the movements represented in the stimuli (roundedness, impressiveness). Results showed that (i) participants' ratings of felt and perceived affect differed, (ii) felt and perceived valence but not arousal ratings correlated with physical parameters of the stimuli (motion energy and luminance), (iii) roundedness in posture shape was related to the experience of more positive emotion than edgy shapes (1 of 3 assessed rounded shapes showed a clear effect on positiveness ratings while a second reached trend level significance), (iv) more impressive movements resulted in more positive affective responses, (v) dance triggered affective experiences through the imagery and autobiographical memories it elicited in some people, and (vi) the physical parameters of the video stimuli correlated only weakly and negatively with the aesthetics ratings of beauty, liking and interest. The novelty of the present approach was twofold; (i) the assessment of multiple affect-inducing mechanisms, and (ii) the use of one single normed stimulus set. The results from this approach lend support to both previous and present findings. Results are discussed with regards to current literature in the field of empirical aesthetics and affective neuroscience. PMID:27235953

  16. Minnowbrook IV: 2003 Workshop on Transition and Unsteady Aspects of Turbomachinery Flows

    NASA Technical Reports Server (NTRS)

    LaGraff, John E. (Editor); Ashpis, David E.

    2004-01-01

    This Minnowbrook IV 2003 workshop on Transition and Unsteady Aspects of Turbomachinery Flows includes the following topics: 1) Current Issues in Unsteady Turbomachinery Flows; 2) Global Instability and Control of Low-Pressure Turbine Flows; 3) Influence of End Wall Leakage on Secondary Flow Development in Axial Turbines; 4) Active and Passive Flow Control on Low Pressure Turbine Airfoils; 5) Experimental and Numerical Investigation of Transitional Flows as Affected by Passing Wakes; 6) Effects of Freestream Turbulence on Turbine Blade Heat Transfer; 7) Bypass Transition Via Continuous Modes and Unsteady Effects on Film Cooling; 8) High Frequency Surface Heat Flux Imaging of Bypass Transition; 9) Skin Friction and Heat Flux Oscillations in Upstream Moving Wave Packets; 10) Transition Mechanisms and Use of Surface Roughness to Enhance the Benefits of Wake Passing in LP Turbines; 11) Transient Growth Approach to Roughness-Induced Transition; 12) Roughness- and Freestream-Turbulence-Induced Transient Growth as a Bypass Transition Mechanism; 13) Receptivity Calculations as a Means to Predicting Transition; 14) On Streamwise Vortices in a Curved Wall Jet and Their Effect on the Mean Flow; 15) Plasma Actuators for Separation Control of Low Pressure Turbine Blades; 16) Boundary-Layer Separation Control Under Low-Pressure-Turbine Conditions Using Glow-Discharge Plasma Actuators; 17) Control of Separation for Low Pressure Turbine Blades: Numerical Simulation; 18) Effects of Elevated Free-Stream Turbulence on Active Control of a Separation Bubble; 19) Wakes, Calming and Transition Under Strong Adverse Pressure Gradients; 20) Transitional Bubble in Periodic Flow Phase Shift; 21) Modelling Spots: The Calmed Region, Pressure Gradient Effects and Background; 22) Modeling of Unsteady Transitional Flow on Axial Compressor Blades; 23) Challenges in Predicting Component Efficiencies in Turbomachines With Low Reynolds Number Blading; 24) Observations on the Causal Relationship Between

  17. Numerical Simulation of Air Bubble Characteristics in Stationary Water

    NASA Astrophysics Data System (ADS)

    Zhang, C. X.; Wang, Y. X.

    The motion of air bubble in water plays a key role in such diverse aspects as air bubble curtain breakwater, air curtain drag reduction, air cushion isolation, weakening the shock wave in water by air bubble screen, etc. At present, the research on air bubble behaviors can be subdivided into several processes: air bubble formation from submerged orifices; interaction and coalescence during the ascending. The work presented in this paper focuses on numerical simulation of air bubble characteristics in stationary water, for example, air bubble formation, the ascending speed, the departing period, and so on. A series of models to simulate the characteristics of air bubble are developed by the VOF method in the two phase flow module of FLUENT. The numerical simulation results are consistent with the theoretical characteristics of air bubble in many aspects. So it is concluded that numerical simulation of air bubble characteristics in stationary water based on FLUENT is feasible. Due to the fact that the characteristics of air bubble are complicated questions, it is important that study on the air bubble behaviors in stationary water should be conducted on deeply.

  18. Feeling worse to feel better: pain-offset relief simultaneously stimulates positive affect and reduces negative affect.

    PubMed

    Franklin, Joseph C; Lee, Kent M; Hanna, Eleanor K; Prinstein, Mitchell J

    2013-04-01

    Although pain itself induces negative affect, the removal (or offset) of pain induces a powerful state of relief. Despite being implicated in a wide range of psychological and behavioral phenomena, relief remains a poorly understood emotion. In particular, some theorists associate relief with increased positive affect, whereas others associate relief with diminished negative affect. In the present study, we examined the affective nature of relief in a pain-offset paradigm with psychophysiological measures that were specific to negative valence (startle eyeblink reactivity) and positive valence (startle postauricular reactivity). Results revealed that pain offset simultaneously stimulates positive affect and diminishes negative affect for at least several seconds. Results also indicated that pain intensity differentially affects the positive and negative valence aspects of relief. These findings clarify the affective nature of relief and provide insight into why people engage in both normal and abnormal behaviors associated with relief.

  19. [Affective disorders: endocrine and metabolic comorbidities].

    PubMed

    Cermolacce, M; Belzeaux, R; Adida, M; Azorin, J-M

    2014-12-01

    Links between affective and endocrine-metabolic disorders are numerous and complex. In this review, we explore most frequent endocrine-metabolic comorbidities. On the one hand, these comorbidities imply numerous iatrogenic effects from antipsychotics (metabolic side-effects) or from lithium (endocrine side-effects). On the other hand, these comorbidities are also associated with affective disorders independently from medication. We will successively examine metabolic syndrome, glycemic disturbances, obesity and thyroid disorders among patients with affective disorders. Endocrinemetabolic comorbidities can be individually encountered, but can also be associated. Therefore, they substantially impact morbidity and mortality by increasing cardiovascular risk factors. Two distinct approaches give an account of processes involved in these comorbidities: common environmental factors (iatrogenic effects, lifestyle), and/or shared physiological vulnerabilities. In conclusion, we provide a synthesis of important results and recommendations related to endocrine-metabolic comorbidities in affective disorders : heavy influence on morbidity and mortality, undertreatment of somatic diseases, importance of endocrine and metabolic side effects from main mood stabilizers, impact from sex and age on the prevalence of comorbidities, influence from previous depressive episodes in bipolar disorders, and relevance of systematic screening for subclinical (biological) disturbances. PMID:25550238

  20. GPU Accelerated Numerical Simulation of Viscous Flow Down a Slope

    NASA Astrophysics Data System (ADS)

    Gygax, Remo; Räss, Ludovic; Omlin, Samuel; Podladchikov, Yuri; Jaboyedoff, Michel

    2014-05-01

    Numerical simulations are an effective tool in natural risk analysis. They are useful to determine the propagation and the runout distance of gravity driven movements such as debris flows or landslides. To evaluate these processes an approach on analogue laboratory experiments and a GPU accelerated numerical simulation of the flow of a viscous liquid down an inclined slope is considered. The physical processes underlying large gravity driven flows share certain aspects with the propagation of debris mass in a rockslide and the spreading of water waves. Several studies have shown that the numerical implementation of the physical processes of viscous flow produce a good fit with the observation of experiments in laboratory in both a quantitative and a qualitative way. When considering a process that is this far explored we can concentrate on its numerical transcription and the application of the code in a GPU accelerated environment to obtain a 3D simulation. The objective of providing a numerical solution in high resolution by NVIDIA-CUDA GPU parallel processing is to increase the speed of the simulation and the accuracy on the prediction. The main goal is to write an easily adaptable and as short as possible code on the widely used platform MATLAB, which will be translated to C-CUDA to achieve higher resolution and processing speed while running on a NVIDIA graphics card cluster. The numerical model, based on the finite difference scheme, is compared to analogue laboratory experiments. This way our numerical model parameters are adjusted to reproduce the effective movements observed by high-speed camera acquisitions during the laboratory experiments.

  1. [Intercultural aspects of the health system reform in Bolivia].

    PubMed

    Ramírez Hita, Susana

    2014-01-01

    This article is a reflection on how interculturality, understood as the way to improve the health of the Bolivian population and coupled with the concept of living well, is not contributing to improving the quality of life and health of the most vulnerable populations in the country. The discourse is coupled with the intention of saving lives in its broadest sense; however, for this it is necessary to make decisions about environmental health and extractivist policies that are not taken into account in the health issues affecting indigenous communities, a population targeted by the intercultural aspects of the health reform. PMID:25597731

  2. [Intercultural aspects of the health system reform in Bolivia].

    PubMed

    Ramírez Hita, Susana

    2014-01-01

    This article is a reflection on how interculturality, understood as the way to improve the health of the Bolivian population and coupled with the concept of living well, is not contributing to improving the quality of life and health of the most vulnerable populations in the country. The discourse is coupled with the intention of saving lives in its broadest sense; however, for this it is necessary to make decisions about environmental health and extractivist policies that are not taken into account in the health issues affecting indigenous communities, a population targeted by the intercultural aspects of the health reform.

  3. Astrophysical Aspects of the Contents of the Input Catalogue

    NASA Astrophysics Data System (ADS)

    Egret, D.; Gómez, E.

    1985-08-01

    The authors illustrate some aspects of the astrophysical contents of the HIPPARCOS Input Catalogue through the comparison of the complete merged file L3 with the file L3/SIM obtained as a result from the first simulation. The following astrophysical topics are considered: the upper part of the HR diagram; the red nearby stars; the distance scale; some problems of galactic structure; old population stars; binary stars with known orbit. The analysis shows, besides a general satisfactory percentage of inclusion for most important programs, an important limitation affecting the faintest red stars, good candidate for parallaxes, but penalized by the observing strategy.

  4. Using anxiolytics in epilepsy: neurobiological, neuropharmacological and clinical aspects.

    PubMed

    Mula, Marco

    2016-09-01

    Anxiety disorders represent a common psychiatric comorbidity in patients with epilepsy, affecting prognosis and quality of life. However, they are still underdiagnosed and undertreated. In clinical practice, a number of compounds are currently used as anxiolytics, with benzodiazepines being the most popular. Other drug classes, especially antiepileptic drugs, are increasingly prescribed for the treatment of anxiety. This article discusses the neurobiological targets and basic neuropharmacological aspects of anxiolytics in order to give the reader clear insight into their activity and mechanism of action. Clinical data regarding the treatment of anxiety in both adults and children with epilepsy are also summarised, emphasising the need for further studies. PMID:27435111

  5. Mycorrhizal aspects in slope stabilisation

    NASA Astrophysics Data System (ADS)

    Graf, Frank

    2016-04-01

    In order to re-colonise and stabilise slopes affected by superficial soil failure with plants essential requirements have to be met: the plants must grow the plants must survive sustainably plant succession must start and continuously develop These requirements, however, are anything but easy given, particularly under the often hostile environmental conditions dominating on bare and steep slopes. Mycorrhizal fungi, the symbiotic partners of almost all plants used in eco-engineering, are said to improve the plants' ability to overcome periods governed by strongly (growth) limiting factors. Subsequently, results of investigations are presented of mycorrhizal effects on different plant and soil functions related to eco-engineering in general and soil and slope stabilisation in particular. Generally, inoculation yielded higher biomass of the host plants above as well as below ground. Furthermore, the survival rate was higher for mycorrhized compared to non-mycorrhized plants, particularly under extreme environmental conditions. However, the scale of the mycorrhizal impact may be species specific of both the plant host as well as the fungal partner(s) and often becomes evident only after a certain time lag. Depending on the plant-fungus combination the root length per soil volume was found to be between 0 and 2.5 times higher for inoculated compared to non-inoculated specimens. On an alpine graded ski slope the survival of inoculated compared to non-treated Salix herbacea cuttings was significant after one vegetation period only for one of the three added mycorrhizal fungus species. However, after three years all of the inoculated plantlets performed significantly better than the non-inoculated controls. The analysis of the potential for producing and stabilising soil aggregates of five different ectomycorrhizal fungi showed high variation and, for the species Inocybe lacera, no significant difference compared to untreated soil. Furthermore, inoculation of Salix

  6. Numerical wave modelling with WAVEWATCH III: numerics and parameterizations for the coastal ocean

    NASA Astrophysics Data System (ADS)

    Ardhuin, F.; Roland, A.; Dutour, M.; Leckler, F.

    2014-12-01

    The development of numerical wave models for coastal applications, including coupling with ocean circulation models, has spurred an on-going effort on theoretical foundations, numerical techniques and physical parameterizations. Some important aspects of this effort are reviewed here, and results are shown in different settings including the French Atlantic, Hawaii and U.S. West Coast, using version 4.18 of the WAVEWATCH III® modelling framework. Compared to previous results, the model errors have been strongly reduced thanks to, among other things, the introduction of currents, coastal reflection, and bottom sediment types. This last item allowed unprecedented accuracy at some sites along the French Atlantic coast. The adequate resolution, necessary to represent strong gradients in tidal currents, was made possible by the efficiency brought by unstructured grids. A further increase in resolution, necessary to resolve surf zones and still cover vast regions is now made possible by the use of implicit schemes. First results with that scheme are presented here and should be made available in a future version 5.xx of WAVEWATCH III.

  7. Aspect ratio dependent fluorescence quenching of eosin Y by gold nanorods.

    PubMed

    Weng, Guojun; Li, Jianjun; Zhang, Li; Zhao, Junwu

    2014-06-01

    Gold nanorods of different aspect ratios had been synthesized using seed mediated growth method. The formed gold nanorods had been characterized by the absorption and transmission electron microscopy (TEM) measurements. The obtained gold nanorods were used to study the quenched effect on fluorescence of Eosin Y. Experimental results revealed that Eosin Y molecules adsorbed on the metallic surfaces, suffering strong quenching of their fluorescence and the quenching efficiency was different for different aspect ratio. Using dielectric coated gold nanorods model, the probable mechanism of aspect ratio dependent quenching efficiency was obtained by numerical calculation based on fluorescence resonance energy transfer and quasi-static theory. The calculation results showed that the non-monotonic changing of fluorescence quenching was attributed to competing effects of aspect ratio and the dielectric constant of coated shell on surface plasmon resonance.

  8. Aspect ratio dependent fluorescence quenching of eosin Y by gold nanorods.

    PubMed

    Weng, Guojun; Li, Jianjun; Zhang, Li; Zhao, Junwu

    2014-06-01

    Gold nanorods of different aspect ratios had been synthesized using seed mediated growth method. The formed gold nanorods had been characterized by the absorption and transmission electron microscopy (TEM) measurements. The obtained gold nanorods were used to study the quenched effect on fluorescence of Eosin Y. Experimental results revealed that Eosin Y molecules adsorbed on the metallic surfaces, suffering strong quenching of their fluorescence and the quenching efficiency was different for different aspect ratio. Using dielectric coated gold nanorods model, the probable mechanism of aspect ratio dependent quenching efficiency was obtained by numerical calculation based on fluorescence resonance energy transfer and quasi-static theory. The calculation results showed that the non-monotonic changing of fluorescence quenching was attributed to competing effects of aspect ratio and the dielectric constant of coated shell on surface plasmon resonance. PMID:24738353

  9. Comparing Happiness and Hypomania Risk: A Study of Extraversion and Neuroticism Aspects.

    PubMed

    Kirkland, Tabitha; Gruber, June; Cunningham, William A

    2015-01-01

    Positive affect has long been considered a hallmark of subjective happiness. Yet, high levels of positive affect have also been linked with hypomania risk: a set of cognitive, affective, and behavioral characteristics that constitute a dispositional risk for future episodes of hypomania and mania. At a personality level, two powerful predictors of affective experience are extraversion and neuroticism: extraversion has been linked to positive affect, and neuroticism to negative affect. As such, a single personality trait--extraversion--has been linked to both beneficial and harmful outcomes associated with positivity. It is clear that positive affect, in different forms, has divergent consequences for well-being, but previous research has struggled to articulate the nature of these differences. We suggest that the relationship between affect and well-being needs to be situated within the psychological context of the individual--both in terms of more specific forms of extraversion and neuroticism, but also in terms of interactions among personality aspects. Consistent with this idea, we found that two aspects of extraversion (enthusiasm and assertiveness) differentially predicted subjective happiness from hypomania risk and two aspects of neuroticism (volatility and withdrawal) interacted to predict hypomania risk: the highest levels of hypomania risk were associated with the combination of high volatility and low withdrawal. These findings underscore the importance of examining personality at the right level of resolution to understand well-being and dysfunction.

  10. Comparing Happiness and Hypomania Risk: A Study of Extraversion and Neuroticism Aspects.

    PubMed

    Kirkland, Tabitha; Gruber, June; Cunningham, William A

    2015-01-01

    Positive affect has long been considered a hallmark of subjective happiness. Yet, high levels of positive affect have also been linked with hypomania risk: a set of cognitive, affective, and behavioral characteristics that constitute a dispositional risk for future episodes of hypomania and mania. At a personality level, two powerful predictors of affective experience are extraversion and neuroticism: extraversion has been linked to positive affect, and neuroticism to negative affect. As such, a single personality trait--extraversion--has been linked to both beneficial and harmful outcomes associated with positivity. It is clear that positive affect, in different forms, has divergent consequences for well-being, but previous research has struggled to articulate the nature of these differences. We suggest that the relationship between affect and well-being needs to be situated within the psychological context of the individual--both in terms of more specific forms of extraversion and neuroticism, but also in terms of interactions among personality aspects. Consistent with this idea, we found that two aspects of extraversion (enthusiasm and assertiveness) differentially predicted subjective happiness from hypomania risk and two aspects of neuroticism (volatility and withdrawal) interacted to predict hypomania risk: the highest levels of hypomania risk were associated with the combination of high volatility and low withdrawal. These findings underscore the importance of examining personality at the right level of resolution to understand well-being and dysfunction. PMID:26161562

  11. Comparing Happiness and Hypomania Risk: A Study of Extraversion and Neuroticism Aspects

    PubMed Central

    Kirkland, Tabitha; Gruber, June; Cunningham, William A.

    2015-01-01

    Positive affect has long been considered a hallmark of subjective happiness. Yet, high levels of positive affect have also been linked with hypomania risk: a set of cognitive, affective, and behavioral characteristics that constitute a dispositional risk for future episodes of hypomania and mania. At a personality level, two powerful predictors of affective experience are extraversion and neuroticism: extraversion has been linked to positive affect, and neuroticism to negative affect. As such, a single personality trait – extraversion – has been linked to both beneficial and harmful outcomes associated with positivity. It is clear that positive affect, in different forms, has divergent consequences for well-being, but previous research has struggled to articulate the nature of these differences. We suggest that the relationship between affect and well-being needs to be situated within the psychological context of the individual – both in terms of more specific forms of extraversion and neuroticism, but also in terms of interactions among personality aspects. Consistent with this idea, we found that two aspects of extraversion (enthusiasm and assertiveness) differentially predicted subjective happiness from hypomania risk and two aspects of neuroticism (volatility and withdrawal) interacted to predict hypomania risk: the highest levels of hypomania risk were associated with the combination of high volatility and low withdrawal. These findings underscore the importance of examining personality at the right level of resolution to understand well-being and dysfunction. PMID:26161562

  12. Multicomputer approach to non-numeric computation

    SciTech Connect

    Baru, C.K.

    1985-01-01

    The architecture of a dynamically partitionable multicomputer system with switchable main memory modules (SM3) for non-numeric computations is studied. The architecture supports efficient execution of parallel algorithms for database processing by (i) allowing the sharing of switchable main memory modules between computers, (ii) supporting network partitioning, and (iii) employing global control lines to efficiently support interprocessor communication. The data transfer time is reduced to memory switching time by allowing some main memory modules to be switched between processors. Network partitioning gives a common bus network system to the capability of an MIMD machine while performing global operations. The global control lines establish a quick and efficient hig-level protocol in the system. The network is supervised by a control computer which oversees network partitioning and other functions. A simulation study of some commonly used database operations, using discrete-event simulation techniques, was carried out, and results of the study are presented. Certain aspects of the system architecture were modified on the basis of simulation results. The general-purpose nature of the SM3 system allows the implementation of a variety of parallel algorithms for database processing.

  13. Numerical simulation of solar coronal magnetic fields

    NASA Technical Reports Server (NTRS)

    Dahlburg, Russell B.; Antiochos, Spiro K.; Zang, T. A.

    1990-01-01

    Many aspects of solar activity are believed to be due to the stressing of the coronal magnetic field by footpoint motions at the photosphere. The results are presented of a fully spectral numerical simulation which is the first 3-D time dependent simulation of footpoint stressing in a geometry appropriate for the corona. An arcade is considered that is initially current-free and impose a smooth footpoint motion that produces a twist in the field of approx 2 pi. The footprints were fixed and the evolution was followed until the field relaxes to another current-free state. No evidence was seen for any instability, either ideal or resistive and no evidence for current sheet formation. The most striking feature of the evolution is that in response to photospheric motions, the field expands rapidly upward to minimize the stress. The expansion has two important effects. First, it suppresses the development of dips in the field that could support dense, cool material. For the motions assumed, the magnetic field does not develop a geometry suitable for prominence formation. Second, the expansion inhibits ideal instabilities such as kinking. The results indicate that simple stearing of a single arcade is unlikely to lead to solar activity such as flares or prominences. Effects are discussed that might possibly lead to such activity.

  14. CBV_ASPECTS Improvement over CT_ASPECTS on Determining Irreversible Ischemic Lesion Decreases over Time

    PubMed Central

    Padroni, Marina; Boned, Sandra; Ribó, Marc; Muchada, Marian; Rodriguez-Luna, David; Coscojuela, Pilar; Tomasello, Alejandro; Cabero, Jordi; Pagola, Jorge; Rodriguez-Villatoro, Noelia; Juega, Jesus M.; Sanjuan, Estela; Molina, Carlos A.; Rubiera, Marta

    2016-01-01

    The Alberta Stroke Program Early CT Score (ASPECTS) is a useful scoring system for assessing early ischemic signs on noncontrast computed tomography (CT). Cerebral blood volume (CBV) on CT perfusion defines the core lesion assumed to be irreversibly damaged. We aim to explore the advantages of CBV_ASPECTS over CT_ASPECTS in the prediction of final infarct volume according to time. Methods Consecutive patients with anterior circulation stroke who underwent endovascular reperfusion according to initial CT_ASPECTS ≥7 were studied. CBV_ASPECTS was assessed blindly later on. Recanalization was defined as thrombolysis in cerebral ischemia score 2b-3. Final infarct volumes were measured on follow-up imaging. We compared ASPECTS on CBV and CT images, and defined ASPECTS agreement as: CT_ASPECTS - CBV_ASPECTS ≤1. Results Sixty-five patients, with a mean age of 67 ± 14 years and a median National Institutes of Health Stroke Scale score of 16 (range 10–20), were studied. The recanalization rate was 78.5%. The median CT_ASPECTS was 9 (range 8–10), and the CBV_ASPECTS was 8 (range 8–10). The mean time from symptoms to CT was 219 ± 143 min. Fifty patients (76.9%) showed ASPECTS agreement. The ASPECTS difference was inversely correlated to the time from symptoms to CT (r = −0.36, p < 0.01). A ROC curve defined 120 min as the best cutoff point after which the ASPECTS difference becomes more frequently ≤1. After 120 min, 89.5% of the patients showed ASPECTS agreement (as compared with 37.5% for <120 min, p < 0.01). CBV_ASPECTS but not CT_ASPECTS correlated with final infarct (r = −0.33, p < 0.01). However, if CT was done >2 h after symptom onset, CT_ASPECTS also correlated to final infarct (r = −0.39, p = 0.01). Conclusions In acute stroke, CBV_ASPECTS correlates with the final infarct volume. However, when CT is performed after 120 min from symptom onset, CBV_ASPECTS does not add relevant information to CT_ASPECTS. PMID:27781042

  15. Effect of tip vortices on membrane vibration of flexible wings with different aspect ratios

    NASA Astrophysics Data System (ADS)

    Genç, Mustafa Serdar; Hakan Açikel, Halil; Demir, Hacımurat; Özden, Mustafa; Çağdaş, Mücahit; Isabekov, Iliasbek

    2016-03-01

    In this study, the effect of the aspect ratio on the aerodynamics characteristic of flexible membrane wings with different aspect ratios (AR = 1 and AR = 3) is experimentally investigated at Reynolds number of 25000. Time accurate measurements of membrane deformation using Digital Image Correlation system (DIC) is carried out while normal forces of the wing will be measured by helping a load-cell system and flow on the wing was visualized by means of smoke wire technic. The characteristics of high aspect ratio wings are shown to be affected by leading edge separation bubbles at low Reynolds number. It is concluded that the camber of membrane wing excites the separated shear layer and this situation increases the lift coefficient relatively more as compared to rigid wings. In membrane wings with low aspect ratio, unsteadiness included tip vortices and vortex shedding, and the combination of tip vortices and vortex shedding causes complex unsteady deformations of these membrane wings. The characteristic of high aspect ratio wings was shown to be affected by leading edge separation bubbles at low Reynolds numbers whereas the deformations of flexible wing with low aspect ratio affected by tip vortices and leading edge separation bubbles.

  16. A new clinical tool for assessing numerical abilities in neurological diseases: numerical activities of daily living.

    PubMed

    Semenza, Carlo; Meneghello, Francesca; Arcara, Giorgio; Burgio, Francesca; Gnoato, Francesca; Facchini, Silvia; Benavides-Varela, Silvia; Clementi, Maurizio; Butterworth, Brian

    2014-01-01

    The aim of this study was to build an instrument, the numerical activities of daily living (NADL), designed to identify the specific impairments in numerical functions that may cause problems in everyday life. These impairments go beyond what can be inferred from the available scales evaluating activities of daily living in general, and are not adequately captured by measures of the general deterioration of cognitive functions as assessed by standard clinical instruments like the MMSE and MoCA. We assessed a control group (n = 148) and a patient group affected by a wide variety of neurological conditions (n = 175), with NADL along with IADL, MMSE, and MoCA. The NADL battery was found to have satisfactory construct validity and reliability, across a wide age range. This enabled us to calculate appropriate criteria for impairment that took into account age and education. It was found that neurological patients tended to overestimate their abilities as compared to the judgment made by their caregivers, assessed with objective tests of numerical abilities. PMID:25126077

  17. A new clinical tool for assessing numerical abilities in neurological diseases: numerical activities of daily living

    PubMed Central

    Semenza, Carlo; Meneghello, Francesca; Arcara, Giorgio; Burgio, Francesca; Gnoato, Francesca; Facchini, Silvia; Benavides-Varela, Silvia; Clementi, Maurizio; Butterworth, Brian

    2014-01-01

    The aim of this study was to build an instrument, the numerical activities of daily living (NADL), designed to identify the specific impairments in numerical functions that may cause problems in everyday life. These impairments go beyond what can be inferred from the available scales evaluating activities of daily living in general, and are not adequately captured by measures of the general deterioration of cognitive functions as assessed by standard clinical instruments like the MMSE and MoCA. We assessed a control group (n = 148) and a patient group affected by a wide variety of neurological conditions (n = 175), with NADL along with IADL, MMSE, and MoCA. The NADL battery was found to have satisfactory construct validity and reliability, across a wide age range. This enabled us to calculate appropriate criteria for impairment that took into account age and education. It was found that neurological patients tended to overestimate their abilities as compared to the judgment made by their caregivers, assessed with objective tests of numerical abilities. PMID:25126077

  18. A new clinical tool for assessing numerical abilities in neurological diseases: numerical activities of daily living.

    PubMed

    Semenza, Carlo; Meneghello, Francesca; Arcara, Giorgio; Burgio, Francesca; Gnoato, Francesca; Facchini, Silvia; Benavides-Varela, Silvia; Clementi, Maurizio; Butterworth, Brian

    2014-01-01

    The aim of this study was to build an instrument, the numerical activities of daily living (NADL), designed to identify the specific impairments in numerical functions that may cause problems in everyday life. These impairments go beyond what can be inferred from the available scales evaluating activities of daily living in general, and are not adequately captured by measures of the general deterioration of cognitive functions as assessed by standard clinical instruments like the MMSE and MoCA. We assessed a control group (n = 148) and a patient group affected by a wide variety of neurological conditions (n = 175), with NADL along with IADL, MMSE, and MoCA. The NADL battery was found to have satisfactory construct validity and reliability, across a wide age range. This enabled us to calculate appropriate criteria for impairment that took into account age and education. It was found that neurological patients tended to overestimate their abilities as compared to the judgment made by their caregivers, assessed with objective tests of numerical abilities.

  19. Environmental Aspects, Objectives and Targets Identification Process

    SciTech Connect

    R. Green

    2002-07-29

    The purpose of this report is to document the environmental aspects and associated environmental impacts of the Bechtel SAIC Company (BSC) scope of work, evaluate the significance of those environmental aspects based on established criteria, and establish environmental objectives and targets for specific environmental aspects. This report is intended to be used by environmental staff in the evaluation of BSC work packages during the annual risk-based planning process. This report shall be fully reviewed and revised annually during the annual work planning process to reflect changes in BSC operations, facilities, and scope of work. Planned BSC work will be evaluated to determine if the work is covered by a previously defined activity, product or service (see Table 2); if work activities require redefinition or addition of a new activity; and if the significant evaluation for each environment aspect is still valid based on scope of planned work. New workscope initiated during the fiscal year through the Baseline Change Proposal process (i.e., not as part of the annual work plan) also will be reviewed for new environmental aspects and determination of whether the new workscope would change the significance rating of any environmental aspect. If a new environmental aspect is identified in a new work activity, product, or service but the aspect is not determined to be significant (see Section 4), then this report can be changed through an interim change notice (ICN). This report can be changed five times through an ICN before a full revision is required. However, if new workscope causes an environmental aspect to be graded as significant using the evaluation process in Section 4, this report shall be revised though a full review and revision.

  20. The histological aspects of fillers complications.

    PubMed

    Zimmermann, Ute S; Clerici, Thierry J

    2004-12-01

    The histological aspects of resorbable heterologous fillers (bovine collagen, acid hyaluronique), autologous fillers (lipofilling, dermis-fat graft), biodegradable fillers (New-Fill), and permanent fillers (silicone, Artecoll, Evolution, Aquamid, DermaLive, DermaDeep, Bioplastique, Paraffin) are described. This article relates the morphological aspect of these materials, the normal tissue reaction after injection, and its chronological evolution as the morphological aspects from the different side effects, more frequently observed for the permanent fillers. They mainly consist of granulomatous reactions which may appear long after injection.

  1. Job satisfaction and importance of work aspects related to predominant values and reactivity.

    PubMed

    Zalewska, A M

    1999-01-01

    The aim of the study is to answer whether 2 predominant values--achievement or social relations--and reactivity influence (a) the importance of work aspects, (b) satisfaction with them and overall job satisfaction, (c) connections between overall job satisfaction and satisfaction with work aspects. Bank employees were investigated with the Strelau Temperament Inventory-Revised by Strelau, Angleitner, Bantelman, and Ruch (1990, reactivity), Orientation to Work Values Inventory by Seifert and Bergmann (1983, values), and Work Description Inventory by Neuberger and Allerbeck (1978; importance and satisfaction with work aspects, overall job satisfaction). Predominant values, reactivity, and their interaction influence the importance of work aspects. The values affect overall job satisfaction and satisfaction with Conditions. Reactivity does not affect overall job satisfaction, but it strongly influences the structure of satisfaction with work aspects, and low-reactives compared to high-reactives are more satisfied with 4 out of the 7 considered aspects. Among the high-reactives, connections between overall job satisfaction and satisfaction with work aspects depend on their predominant values. It was concluded that reactivity can modify regulative functions of personal values towards overall job satisfaction: The values have a rather declarative character for low-reactives, but meeting aspirations connected with their values is very important for high-reactives' job satisfaction. PMID:10657923

  2. Numerical weather forecasting with anelastic model

    NASA Astrophysics Data System (ADS)

    Wójcik, Damian; Kurowski, Marcin; Piotrowski, Zbigniew; Rosa, Bogdan; Ziemiański, Michał

    2013-04-01

    Research conducted at Polish Institute of Meteorology and Water Management, National Research Institute, in collaboration with Consortium for Small Scale Modeling (COSMO) are aimed at developing new conservative dynamical core for next generation operational weather prediction model. Within the frames of the project a new prototype model has been developed. The dynamical core of the model is based on anelastic set of equation and numerics adopted from the EULAG model. An employment of EULAG allowed to profit from its desirable conservative properties and numerical robustness confirmed in number of benchmark tests and widely documented in scientific literature. The first stage of the project has been already successfully completed. Its main achievement is a hybrid model capable to compute weather forecast. The model consists of EULAG dynamical core implemented into the software environment of the operational COSMO model and basic COSMO physical parameterizations involving turbulence, friction, radiation, moist processes and surface fluxes (COSMO-EULAG). The presentation shows the case studies comparing results of 24-hour forecasts calculated via the hybrid model with analogous results obtained with the Runge-Kutta dynamical core standard for the COSMO operational applications. The experiments are performed with 2.2 km resolution over Alpine domain of operational MeteoSwiss numerical forecasts. The results demonstrate that the short-term forecasts employing different dynamical cores are qualitatively and quantitatively similar, especially in the middle and upper troposphere. Near the surface the COSMO-EULAG results, while similar to the Runge-Kutta ones, show more small-scale variability. It is seen that the anelastic approximation does not impose measurable adverse affects on the forecast. The presentation shows also results of another class of experiments. They involve 24-hour forecast with COSMO-EULAG over realistic Alpine domain with the horizontal resolutions of

  3. Numerical assessment of the stiffness index.

    PubMed

    Epstein, Sally; Vergnaud, Anne-Claire; Elliott, Paul; Chowienczyk, Phil; Alastruey, Jordi

    2014-01-01

    Elevated systemic vascular stiffness is associated with increased risk of cardiovascular disease. It has been suggested that the time difference between the two characteristic peaks of the digital volume pulse (DVP) measured at the finger using photoplethysmography is related to the stiffness of the arterial tree, and inversely proportional to the stiffness index (SI). However, the precise physical meaning of the SI and its relation to aortic pulse wave velocity (aPWV) is yet to be ascertained. In this study we investigated numerically the effect of changes in arterial wall stiffness, peripheral resistances, peripheral compliances or peripheral wave reflections on the SI and aPWV. The SI was calculated from the digital area waveform simulated using a nonlinear one-dimensional model of pulse wave propagation in a 75-artery network, which includes the larger arteries of the hand. Our results show that aPWV is affected by changes in aortic stiffness, but the SI is primarily affected by changes in the stiffness of all conduit vessels. Thus, the SI is not a direct substitute for aPWV. Moreover, our results suggest that peripheral reflections in the upper body delay the time of arrival of the first peak in the DVP. The second peak is predominantly caused by the impedance mismatch within the 75 arterial segments, rather than by peripheral reflections.

  4. A numerical study of separation on a spheroid at incidence

    NASA Technical Reports Server (NTRS)

    Rosenfeld, M.; Israeli, M.; Wolfshtein, M.

    1986-01-01

    The three-dimensional incompressible, steady and laminar flow field around a prolate spheroid at incidence is considered. The parabolized Navier-Stokes equations are solved numerically. The method can handle vortex types as well as bubble type flow separation because the pressure is one of the dependent variables. Here, the distribution of the skin friction is reported for two test cases. The first test case is a prolate spheroid of aspect ratio of 4:1 at 6 degrees incidence and Reynolds number of 1 million (based on half the major axis). The second case is a spheroid with a 6:1 aspect ratio at 10 degrees incidence and Reynolds number of 0.8 x 1 million. The properties of the flow field near the body are discussed on the basis of the pattern of the skin friction lines, and the shape of the separation lines. Favorable agreement with experimental results is obtained.

  5. Numerical simulation of electrochemical desalination

    NASA Astrophysics Data System (ADS)

    Hlushkou, D.; Knust, K. N.; Crooks, R. M.; Tallarek, U.

    2016-05-01

    We present an effective numerical approach to simulate electrochemically mediated desalination of seawater. This new membraneless, energy efficient desalination method relies on the oxidation of chloride ions, which generates an ion depletion zone and local electric field gradient near the junction of a microchannel branch to redirect sea salt into the brine stream, consequently producing desalted water. The proposed numerical model is based on resolution of the 3D coupled Navier-Stokes, Nernst-Planck, and Poisson equations at non-uniform spatial grids. The model is implemented as a parallel code and can be employed to simulate mass-charge transport coupled with surface or volume reactions in 3D systems showing an arbitrarily complex geometrical configuration.

  6. Numerical Modeling of LCROSS experiment

    NASA Astrophysics Data System (ADS)

    Sultanov, V. G.; Kim, V. V.; Matveichev, A. V.; Zhukov, B. G.; Lomonosov, I. V.

    2009-06-01

    The mission objectives of the Lunar Crater Observation and Sensing Satellite (LCROSS) include confirming the presence or absence of water ice in a permanently shadowed crater in the Moon's polar regions. In this research we present results of numerical modeling of forthcoming LCROSS experiment. The parallel FPIC3D gas dynamic code with implemented realistic equations of state (EOS) and constitutive relations [1] was used. New wide--range EOS for lunar ground was developed. We carried out calculations of impact of model body on the lunar surface at different angels. Situations of impact on dry and water ice--contained lunar ground were also taken into account. Modeling results are given for crater's shape and size along with amount of ejecta. [4pt] [1] V.E. Fortov, V.V. Kim, I.V. Lomonosov, A.V. Matveichev, A.V. Ostrik. Numerical modeling of hypervelocity impacts, Intern J Impact Engeneering, 33, 244-253 (2006)

  7. Numerical simulation of heat exchanger

    SciTech Connect

    Sha, W.T.

    1985-01-01

    Accurate and detailed knowledge of the fluid flow field and thermal distribution inside a heat exchanger becomes invaluable as a large, efficient, and reliable unit is sought. This information is needed to provide proper evaluation of the thermal and structural performance characteristics of a heat exchanger. It is to be noted that an analytical prediction method, when properly validated, will greatly reduce the need for model testing, facilitate interpolating and extrapolating test data, aid in optimizing heat-exchanger design and performance, and provide scaling capability. Thus tremendous savings of cost and time are realized. With the advent of large digital computers and advances in the development of computational fluid mechanics, it has become possible to predict analytically, through numerical solution, the conservation equations of mass, momentum, and energy for both the shellside and tubeside fluids. The numerical modeling technique will be a valuable, cost-effective design tool for development of advanced heat exchangers.

  8. Numerical simulation of electrochemical desalination.

    PubMed

    Hlushkou, D; Knust, K N; Crooks, R M; Tallarek, U

    2016-05-18

    We present an effective numerical approach to simulate electrochemically mediated desalination of seawater. This new membraneless, energy efficient desalination method relies on the oxidation of chloride ions, which generates an ion depletion zone and local electric field gradient near the junction of a microchannel branch to redirect sea salt into the brine stream, consequently producing desalted water. The proposed numerical model is based on resolution of the 3D coupled Navier-Stokes, Nernst-Planck, and Poisson equations at non-uniform spatial grids. The model is implemented as a parallel code and can be employed to simulate mass-charge transport coupled with surface or volume reactions in 3D systems showing an arbitrarily complex geometrical configuration.

  9. Numerical modeling of Waianae Harbor

    SciTech Connect

    Mader, C.L.; Lucas, S.

    1985-01-01

    The Waianae harbor problem is an example of the use of numerical modeling techniques available at JTRE of the University of Hawaii to assist in the evaluation of oceanographic fluid dynamic flow problems. The numerical techniques are available to assist in the modeling of many problems of interest to the Hawaii Ocean Experiment. One application that has received considerable effort is the formation, propagation, and run-up of tsunami waves. The interaction of tsunami waves with the island chain is an important problem that needs more study. The models can be used to study storm surge interaction with the Hawaii islands and current and circulation around and through the islands. It is important that the modeling not be limited to the usual nonlinear shallow-water models, since they are inappropriate for many of the problems of interest to the Hawaii Ocean Experiment. 6 references, 5 figures.

  10. Numerical simulation of electrochemical desalination.

    PubMed

    Hlushkou, D; Knust, K N; Crooks, R M; Tallarek, U

    2016-05-18

    We present an effective numerical approach to simulate electrochemically mediated desalination of seawater. This new membraneless, energy efficient desalination method relies on the oxidation of chloride ions, which generates an ion depletion zone and local electric field gradient near the junction of a microchannel branch to redirect sea salt into the brine stream, consequently producing desalted water. The proposed numerical model is based on resolution of the 3D coupled Navier-Stokes, Nernst-Planck, and Poisson equations at non-uniform spatial grids. The model is implemented as a parallel code and can be employed to simulate mass-charge transport coupled with surface or volume reactions in 3D systems showing an arbitrarily complex geometrical configuration. PMID:27089841

  11. Cuba: Multidimensional numerical integration library

    NASA Astrophysics Data System (ADS)

    Hahn, Thomas

    2016-08-01

    The Cuba library offers four independent routines for multidimensional numerical integration: Vegas, Suave, Divonne, and Cuhre. The four algorithms work by very different methods, and can integrate vector integrands and have very similar Fortran, C/C++, and Mathematica interfaces. Their invocation is very similar, making it easy to cross-check by substituting one method by another. For further safeguarding, the output is supplemented by a chi-square probability which quantifies the reliability of the error estimate.

  12. Elements affecting runway traction

    NASA Technical Reports Server (NTRS)

    Horne, W. B.

    1974-01-01

    The five basic elements affecting runway traction for jet transport aircraft operation are identified and described in terms of pilot, aircraft system, atmospheric, tire, and pavement performance factors or parameters. Where possible, research results are summarized, and means for restoring or improving runway traction for these different conditions are discussed.

  13. What Variables Affect Solubility?

    ERIC Educational Resources Information Center

    Baker, William P.; Leyva, Kathryn

    2003-01-01

    Helps middle school students understand the concept of solubility through hands-on experience with a variety of liquids and solids. As they explore factors that affect solubility and saturation, students gain content mastery and an understanding of the inquiry process. Also enables teachers to authentically assess student performance on several…

  14. How Body Affects Brain.

    PubMed

    Suzuki, Wendy A

    2016-08-01

    Studies show that physical exercise can affect a range of brain and cognitive functions. However, little is known about the peripheral signals that initiate these central changes. Moon et al. (2016) provide exciting new evidence that a novel myokine, cathepsin B (CTSB), released with exercise is associated with improved memory. PMID:27508865

  15. Food Affects Human Behavior.

    ERIC Educational Resources Information Center

    Kolata, Gina

    1982-01-01

    A conference on whether food and nutrients affect human behavior was held on November 9, 1982 at the Massachusetts Institute of Technology. Various research studies on this topic are reviewed, including the effects of food on brain biochemistry (particularly sleep) and effects of tryptophane as a pain reducer. (JN)

  16. Factors affecting soil cohesion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil erodibility is a measure of a soil’s resistance against erosive forces and is affected by both intrinsic (or inherent) soil property and the extrinsic condition at the time erodibility measurement is made. Since soil erodibility is usually calculated from results obtained from erosion experimen...

  17. Affective antecedents of revenge.

    PubMed

    O'Connor, Kieran; Adams, Gabrielle S

    2013-02-01

    We propose that revenge responses are often influenced more by affective reactions than by deliberate decision making as McCullough et al. suggest. We review social psychological evidence suggesting that justice judgments and reactions may be determined more by emotions than by cognitions.

  18. Requirements definition by numerical simulation

    NASA Astrophysics Data System (ADS)

    Hickman, James J.; Kostas, Chris; Tsang, Kang T.

    1994-10-01

    We are investigating the issues involved in requirements definition for narcotics interdiction: how much of a particular signature is possible, how does this amount change for different conditions, and what is the temporal relationship in various scenarios. Our approach has been to simulate numerically the conditions that arise during vapor or particulate transport. The advantages of this approach are that (1) a broad range of scenarios can be rapidly and inexpensively analyzed by simulation, and (2) simulations can display quantities that are difficult or impossible to measure. The drawback of this approach is that simulations cannot include all of the phenomena present in a real measurement, and therefore the fidelity of the simulation results is always an issue. To address this limitation, we will ultimately combine the results of numerical simulations with measurements of physical parameters for inclusion in the simulation. In this paper, we discuss these issues and how they apply to the current problems in narcotics interdictions, especially cargo containers. We also show the results of 1D and 3D numerical simulations, and compare these results with analytical solutions. The results indicate that this approach is viable. We also present data from 3D simulations of vapor transport in a loaded cargo container and some of the issues present in this ongoing work.

  19. In Praise of Numerical Computation

    NASA Astrophysics Data System (ADS)

    Yap, Chee K.

    Theoretical Computer Science has developed an almost exclusively discrete/algebraic persona. We have effectively shut ourselves off from half of the world of computing: a host of problems in Computational Science & Engineering (CS&E) are defined on the continuum, and, for them, the discrete viewpoint is inadequate. The computational techniques in such problems are well-known to numerical analysis and applied mathematics, but are rarely discussed in theoretical algorithms: iteration, subdivision and approximation. By various case studies, I will indicate how our discrete/algebraic view of computing has many shortcomings in CS&E. We want embrace the continuous/analytic view, but in a new synthesis with the discrete/algebraic view. I will suggest a pathway, by way of an exact numerical model of computation, that allows us to incorporate iteration and approximation into our algorithms’ design. Some recent results give a peek into how this view of algorithmic development might look like, and its distinctive form suggests the name “numerical computational geometry” for such activities.

  20. Numerical simulation of conservation laws

    NASA Technical Reports Server (NTRS)

    Chang, Sin-Chung; To, Wai-Ming

    1992-01-01

    A new numerical framework for solving conservation laws is being developed. This new approach differs substantially from the well established methods, i.e., finite difference, finite volume, finite element and spectral methods, in both concept and methodology. The key features of the current scheme include: (1) direct discretization of the integral forms of conservation laws, (2) treating space and time on the same footing, (3) flux conservation in space and time, and (4) unified treatment of the convection and diffusion fluxes. The model equation considered in the initial study is the standard one dimensional unsteady constant-coefficient convection-diffusion equation. In a stability study, it is shown that the principal and spurious amplification factors of the current scheme, respectively, are structurally similar to those of the leapfrog/DuFort-Frankel scheme. As a result, the current scheme has no numerical diffusion in the special case of pure convection and is unconditionally stable in the special case of pure diffusion. Assuming smooth initial data, it will be shown theoretically and numerically that, by using an easily determined optimal time step, the accuracy of the current scheme may reach a level which is several orders of magnitude higher than that of the MacCormack scheme, with virtually identical operation count.

  1. Blepharospasm: Update on Epidemiology, Clinical Aspects, and Pathophysiology

    PubMed Central

    Valls-Sole, Josep; Defazio, Giovanni

    2016-01-01

    Blepharospasm (BSP) is a rather distressing form of focal dystonia. Although many aspects of its pathophysiological mechanisms are already known, we lack fundamental evidence on etiology, prevention, and treatment. To advance in our knowledge, we need to review what is already known in various aspects of the disorder and use these bases to find future lines of interest. Some of the signs observed in BSP are cause, while others are consequence of the disorder. Non-motor symptoms and signs may be a cue for understanding better the disease. Various cerebral sites have been shown to be functionally abnormal in BSP, including the basal ganglia, the cortex, and the cerebellum. However, we still do not know if the dysfunction or structural change affecting these brain regions is cause or consequence of BSP. Further advances in neurophysiology and neuroimaging may eventually clarify the pathophysiological mechanisms implicated. In this manuscript, we aim to update what is known regarding epidemiology, clinical aspects, and pathophysiology of the disorder and speculate on the directions of research worth pursuing in the near future. PMID:27064462

  2. Psychosocial aspects of fertility behavior: an overview.

    PubMed

    David, H P

    1981-06-01

    Selected aspects of decision making in fertility behavior are reviewed. Attention is directed to assessing motivational determinants, the value of children, the concept of "wantedness," delayed childbearing, and adolescent fertility. A woman's decision to use or not to use a birth control method is heavily influenced by partner interaction. The perception of the partner's attitudes and degree of control in the couple relationship are likely to affect the type of method used, the consistency of contraceptive practice, and the resolution of eventual pregnancies. The present generation in many countries is the 1st to be involved in the conscious process of deciding when and how many children to have and to discontinue contraception. The psychosocial model of fertility behaviour emphasizes the subjective assessment of the environment by the individual and the importance of the 2 partners in a couple influencing each other's perceptions and choice behavior. A key feature of successful couple planning behavior is their joint ability to anticipate future outcomes, plan ahead, and develop contingency alternatives. The history of attempts to explain and delineate motivational determinants of fertility behavior is long and filled with testimonials regarding the complexity of the task. It has been well documented in cross-national studies and commentaries that the pleasures which parents experience in raising their children are highly valued. The gradual transition in the perceived economic value of children probably reflects changing parental attitudes accompanying the secular decline in fertility rates. Reducing the number of unwanted pregnancies has been and continues to be one of the major objectives of international planned parenthood and responsible parenthood movements. No published evidence exists, however, that the unexpected, unplanned, or even unwanted pregnancy is always "bad" or that a planned pregnancy more often produces a psychologically healthy child. To date

  3. Psychosocial aspects of fertility behavior: an overview.

    PubMed

    David, H P

    1981-06-01

    Selected aspects of decision making in fertility behavior are reviewed. Attention is directed to assessing motivational determinants, the value of children, the concept of "wantedness," delayed childbearing, and adolescent fertility. A woman's decision to use or not to use a birth control method is heavily influenced by partner interaction. The perception of the partner's attitudes and degree of control in the couple relationship are likely to affect the type of method used, the consistency of contraceptive practice, and the resolution of eventual pregnancies. The present generation in many countries is the 1st to be involved in the conscious process of deciding when and how many children to have and to discontinue contraception. The psychosocial model of fertility behaviour emphasizes the subjective assessment of the environment by the individual and the importance of the 2 partners in a couple influencing each other's perceptions and choice behavior. A key feature of successful couple planning behavior is their joint ability to anticipate future outcomes, plan ahead, and develop contingency alternatives. The history of attempts to explain and delineate motivational determinants of fertility behavior is long and filled with testimonials regarding the complexity of the task. It has been well documented in cross-national studies and commentaries that the pleasures which parents experience in raising their children are highly valued. The gradual transition in the perceived economic value of children probably reflects changing parental attitudes accompanying the secular decline in fertility rates. Reducing the number of unwanted pregnancies has been and continues to be one of the major objectives of international planned parenthood and responsible parenthood movements. No published evidence exists, however, that the unexpected, unplanned, or even unwanted pregnancy is always "bad" or that a planned pregnancy more often produces a psychologically healthy child. To date

  4. Aspects of prehistoric astronomy in India

    NASA Astrophysics Data System (ADS)

    Rao, N. Kameswara

    2005-12-01

    Some archeoastronomical aspects regarding the development of observational astronomy in India during prehistoric times are described. A plea is made for the preservation of megalithic monuments of possible astronomical significance.

  5. Multiple sclerosis: Experimental and clinical aspects

    SciTech Connect

    Scheinberg, L.; Raine, C.S.

    1984-01-01

    This book discusses the experimental and clinical aspects of multiple sclerosis. Specifically discussed are - Association of Epstein Barr Virus with pathology of central nervous system; immunology of viruses; and immunosuppression.

  6. Some Legal Aspects of Higher Education

    ERIC Educational Resources Information Center

    Kowalski, Casimir J.; And Others

    1977-01-01

    This article explores some legal aspects of public and private education, as well as several Amendments to the Constitution and their relationships to higher education: the First, Fourth, Fifth, Sixth, and Fourteenth Amendments. (Author)

  7. [Communication in health care - legal aspects].

    PubMed

    Mina, András

    2016-04-24

    This paper is focusing on the legal aspects of communication in health care, especially on doctor-patient relationship, responsibility for information, communication of adverse events, and legal declarations. PMID:27084442

  8. Herbal-caffeinated chewing gum, but not bubble gum, improves aspects of memory.

    PubMed

    Davidson, Matthew G

    2011-08-01

    Research has shown that standard chewing gum can affect aspects of both attention and memory. The present study examined the effects of Think Gum®, a caffeinated-herbal chewing gum, on both concentration and memory using a series of paper-based and online testing. Compared to standard chewing gum and a no-gum control, chewing caffeinated-herbal gum during testing improved aspects of memory, but did not affect concentration. The findings suggest that caffeinated-herbal chewing gum is an effective memory aid.

  9. Herbal-caffeinated chewing gum, but not bubble gum, improves aspects of memory.

    PubMed

    Davidson, Matthew G

    2011-08-01

    Research has shown that standard chewing gum can affect aspects of both attention and memory. The present study examined the effects of Think Gum®, a caffeinated-herbal chewing gum, on both concentration and memory using a series of paper-based and online testing. Compared to standard chewing gum and a no-gum control, chewing caffeinated-herbal gum during testing improved aspects of memory, but did not affect concentration. The findings suggest that caffeinated-herbal chewing gum is an effective memory aid. PMID:21570431

  10. [A current and global review of sweeteners. Regulatory aspects].

    PubMed

    García-Almeida, J M; Casado Fdez, Gracia M; García Alemán, J

    2013-07-01

    In this chapter we review the role and potential benefits of non-caloric sweeteners, as part of the diet. After appearing and interest in the beneficial effects attributed to them, face different situations and conditions (obesity, diabetes...), more and more numerous studies, show their ineffective use. In conclusion, further research and results are needed to provide convincing evidence of their long-term effectiveness and the absence of negative effects from their use. The interest of the chapter lies in examining the distinctive aspects of sweeteners compared with sugar, measured as the standard of comparison. We will focus then on the other substances that are commonly used to sweeten foods instead of sugar.

  11. Aspect-ratio dependence of thermodynamic Casimir forces

    NASA Astrophysics Data System (ADS)

    Hucht, Alfred; Grueneberg, Daniel; Schmidt, Felix M.

    2012-02-01

    We consider the three-dimensional Ising model in a LxLxL cuboid geometry with finite aspect ratio ρ=L/L and periodic boundary conditions along all directions. For this model the finite-size scaling functions of the excess free energy and thermodynamic Casimir force are evaluated numerically by means of Monte Carlo simulations [1]. The Monte Carlo results compare well with recent field theoretical results for the Ising universality class at temperatures above and slightly below the bulk critical temperature Tc. Furthermore, the excess free energy and Casimir force scaling functions of the two-dimensional Ising model are calculated exactly for arbitrary ρ and compared to the three-dimensional case. We give a general argument that the Casimir force vanishes at the critical point for ρ=1 and becomes repulsive in periodic systems for ρ>1. [4pt] [1] Alfred Hucht, Daniel Gr"uneberg, and Felix M. Schmidt, Phys. Rev. E 83, 051101 (2011)

  12. Feasibility study for a numerical aerodynamic simulation facility: Summary

    NASA Technical Reports Server (NTRS)

    Lincoln, N. R.

    1979-01-01

    The Ames Research Center of NASA is engaged in the development and investigation of numerical methods and computer technologies to be employed in conjunction with physical experiments, particularly utilizing wind tunnels in the furtherance of the field of aircraft and aerodynamic body design. Several studies, aimed primarily at the areas of development and production of extremely high-speed computing facilities, were conducted. The studies focused on evaluating the aspects of feasibility, reliability, costs, and practicability of designing, constructing, and bringing into effect production of a special-purpose system. An executive summary of the activities for this project is presented in this volume.

  13. Definition of sanitary boundaries to prevent ISAv spread between salmon farms in southern Chile based on numerical simulations of currents

    NASA Astrophysics Data System (ADS)

    Olivares, Gonzalo; Sepúlveda, H. H.; Yannicelli, B.

    2015-06-01

    The infectious Salmon Anemia virus (ISAv) is a pathogen that mainly affects the Atlantic Salmon (Salmo salar). It was detected in Norway in 1984 and in June 2007 appeared in Chile, producing a drop of more than 30% in the country's production level. It is expected that with certain regularity, outbreaks will continue to appear in Chile without the need of reintroducing the virus from foreign countries. We present a numerical study of the influence of winds and tides in the dispersion of lagrangian particles to simulate the transport of ISAv in the Aysen region, in southern Chile. This study combines the use of numerical models of the ocean and atmosphere, lagrangian tracking and biological aspects of ISAv infections. As in previous results, a wider dispersion of ISAv was observed during spring tides. Temporal changes in wind significantly modified the transport of viral particles from an infected center. Under similar forcing conditions, the areas of risk associated to culture sites separated by a few kilometers could be very different. Our main results remark the importance of the use of a detailed knowledge of hydrographic and atmospheric circulation in the definition of boundaries for sanitary management areas. We suggest that a methodology similar to the one presented in this study should be considered to define sanitary strategies to minimize the occurrence of native outbreaks of ISAv.

  14. Approaches to high aspect ratio triangulations

    NASA Technical Reports Server (NTRS)

    Posenau, M.-A.

    1993-01-01

    In aerospace computational fluid dynamics calculations, high aspect ratio, or stretched, triangulations are necessary to adequately resolve the features of a viscous flow around bodies. In this paper, we explore alternatives to the Delaunay triangulation which can be used to generate high aspect ratio triangulations of point sets. The method is based on a variation of the lifting map concept which derives Delaunay triangulations from convex hull calculations.

  15. Technical aspects of ileoanal pouch surgery.

    PubMed

    Carne, Peter W G; Pemberton, John H

    2004-02-01

    Ileal pouch-anal anastomosis has become the surgical procedure of choice for chronic ulcerative colitis. Since the initial description of the technique, various modifications have facilitated its evolution into a safe operation with excellent long-term outcomes. However, some aspects of the operation remain contentious. Our aim is to describe the technical aspects of ileal pouch-anal anastomosis and review the current literature in the areas of controversy.

  16. Practical aspects of telehealth: financial considerations.

    PubMed

    Loh, P K; Sabesan, S; Allen, D; Caldwell, P; Mozer, R; Komesaroff, P A; Talman, P; Williams, M; Shaheen, N; Grabinski, O; Withnall, D

    2013-07-01

    The second in a series of articles about the practical aspects of telehealth, this paper includes information and a case history on the cost-benefits for patients and practitioners using telehealth. The case history demonstrates that telehealth can save travel time for patients, carers and specialists, and can reduce out-of-pocket expenses. The practical aspects of telehealth article series considers the contextual, clinical, technical and ethical components of online video consultations.

  17. A Comparison of Metamodeling Techniques via Numerical Experiments

    NASA Technical Reports Server (NTRS)

    Crespo, Luis G.; Kenny, Sean P.; Giesy, Daniel P.

    2016-01-01

    This paper presents a comparative analysis of a few metamodeling techniques using numerical experiments for the single input-single output case. These experiments enable comparing the models' predictions with the phenomenon they are aiming to describe as more data is made available. These techniques include (i) prediction intervals associated with a least squares parameter estimate, (ii) Bayesian credible intervals, (iii) Gaussian process models, and (iv) interval predictor models. Aspects being compared are computational complexity, accuracy (i.e., the degree to which the resulting prediction conforms to the actual Data Generating Mechanism), reliability (i.e., the probability that new observations will fall inside the predicted interval), sensitivity to outliers, extrapolation properties, ease of use, and asymptotic behavior. The numerical experiments describe typical application scenarios that challenge the underlying assumptions supporting most metamodeling techniques.

  18. Numerical Relativity Simulations for Black Hole Merger Astrophysics

    NASA Technical Reports Server (NTRS)

    Baker, John G.

    2010-01-01

    Massive black hole mergers are perhaps the most energetic astronomical events, establishing their importance as gravitational wave sources for LISA, and also possibly leading to observable influences on their local environments. Advances in numerical relativity over the last five years have fueled the development of a rich physical understanding of general relativity's predictions for these events. Z will overview the understanding of these event emerging from numerical simulation studies. These simulations elucidate the pre-merger dynamics of the black hole binaries, the consequent gravitational waveform signatures ' and the resulting state, including its kick velocity, for the final black hole produced by the merger. Scenarios are now being considered for observing each of these aspects of the merger, involving both gravitational-wave and electromagnetic astronomy.

  19. SToRM: A numerical model for environmental surface flows

    USGS Publications Warehouse

    Simoes, Francisco J.

    2009-01-01

    SToRM (System for Transport and River Modeling) is a numerical model developed to simulate free surface flows in complex environmental domains. It is based on the depth-averaged St. Venant equations, which are discretized using unstructured upwind finite volume methods, and contains both steady and unsteady solution techniques. This article provides a brief description of the numerical approach selected to discretize the governing equations in space and time, including important aspects of solving natural environmental flows, such as the wetting and drying algorithm. The presentation is illustrated with several application examples, covering both laboratory and natural river flow cases, which show the model’s ability to solve complex flow phenomena.

  20. Centrifugal pump inlet pressure site affects measurement.

    PubMed

    Augustin, Simon; Horton, Alison; Butt, Warwick; Bennett, Martin; Horton, Stephen

    2010-09-01

    During extracorporeal life support (ECLS), blood is exposed to a myriad of unphysiological factors that can affect outcome. One aspect of this is the sub-atmospheric pressure generated by the ECLS pump and imparted to blood elements along the pump inlet line. This pressure can be measured on the inlet line close to the pump head by adding a connector, or at the venous cannula connection site. We compared the two measurement sites located at both points; between the venous cannula-inlet tubing and inlet tubing-pump, with a range of cannulae and flows. We also investigated the effects on inlet pressure from pump afterload and increasing inlet tubing length.

  1. Dynamic Synchronization of Teacher-Students Affection in Affective Instruction

    ERIC Educational Resources Information Center

    Zhang, Wenhai; Lu, Jiamei

    2011-01-01

    Based on Bower's affective network theory, the article links the dynamic analysis of affective factors in affective instruction, and presents affective instruction strategic of dynamic synchronization between teacher and students to implement the best ideal mood that promotes students' cognition and affection together. In the process of teaching,…

  2. Dynamic musical communication of core affect

    PubMed Central

    Flaig, Nicole K.; Large, Edward W.

    2013-01-01

    Is there something special about the way music communicates feelings? Theorists since Meyer (1956) have attempted to explain how music could stimulate varied and subtle affective experiences by violating learned expectancies, or by mimicking other forms of social interaction. Our proposal is that music speaks to the brain in its own language; it need not imitate any other form of communication. We review recent theoretical and empirical literature, which suggests that all conscious processes consist of dynamic neural events, produced by spatially dispersed processes in the physical brain. Intentional thought and affective experience arise as dynamical aspects of neural events taking place in multiple brain areas simultaneously. At any given moment, this content comprises a unified “scene” that is integrated into a dynamic core through synchrony of neuronal oscillations. We propose that (1) neurodynamic synchrony with musical stimuli gives rise to musical qualia including tonal and temporal expectancies, and that (2) music-synchronous responses couple into core neurodynamics, enabling music to directly modulate core affect. Expressive music performance, for example, may recruit rhythm-synchronous neural responses to support affective communication. We suggest that the dynamic relationship between musical expression and the experience of affect presents a unique opportunity for the study of emotional experience. This may help elucidate the neural mechanisms underlying arousal and valence, and offer a new approach to exploring the complex dynamics of the how and why of emotional experience. PMID:24672492

  3. Dynamic musical communication of core affect.

    PubMed

    Flaig, Nicole K; Large, Edward W

    2014-01-01

    Is there something special about the way music communicates feelings? Theorists since Meyer (1956) have attempted to explain how music could stimulate varied and subtle affective experiences by violating learned expectancies, or by mimicking other forms of social interaction. Our proposal is that music speaks to the brain in its own language; it need not imitate any other form of communication. We review recent theoretical and empirical literature, which suggests that all conscious processes consist of dynamic neural events, produced by spatially dispersed processes in the physical brain. Intentional thought and affective experience arise as dynamical aspects of neural events taking place in multiple brain areas simultaneously. At any given moment, this content comprises a unified "scene" that is integrated into a dynamic core through synchrony of neuronal oscillations. We propose that (1) neurodynamic synchrony with musical stimuli gives rise to musical qualia including tonal and temporal expectancies, and that (2) music-synchronous responses couple into core neurodynamics, enabling music to directly modulate core affect. Expressive music performance, for example, may recruit rhythm-synchronous neural responses to support affective communication. We suggest that the dynamic relationship between musical expression and the experience of affect presents a unique opportunity for the study of emotional experience. This may help elucidate the neural mechanisms underlying arousal and valence, and offer a new approach to exploring the complex dynamics of the how and why of emotional experience. PMID:24672492

  4. The Thomas–Fermi quark model: Non-relativistic aspects

    SciTech Connect

    Liu, Quan Wilcox, Walter

    2014-02-15

    The first numerical investigation of non-relativistic aspects of the Thomas–Fermi (TF) statistical multi-quark model is given. We begin with a review of the traditional TF model without an explicit spin interaction and find that the spin splittings are too small in this approach. An explicit spin interaction is then introduced which entails the definition of a generalized spin “flavor”. We investigate baryonic states in this approach which can be described with two inequivalent wave functions; such states can however apply to multiple degenerate flavors. We find that the model requires a spatial separation of quark flavors, even if completely degenerate. Although the TF model is designed to investigate the possibility of many-quark states, we find surprisingly that it may be used to fit the low energy spectrum of almost all ground state octet and decuplet baryons. The charge radii of such states are determined and compared with lattice calculations and other models. The low energy fit obtained allows us to extrapolate to the six-quark doubly strange H-dibaryon state, flavor symmetric strange states of higher quark content and possible six quark nucleon–nucleon resonances. The emphasis here is on the systematics revealed in this approach. We view our model as a versatile and convenient tool for quickly assessing the characteristics of new, possibly bound, particle states of higher quark number content. -- Highlights: • First application of the statistical Thomas–Fermi quark model to baryonic systems. • Novel aspects: spin as generalized flavor; spatial separation of quark flavor phases. • The model is statistical, but the low energy baryonic spectrum is successfully fit. • Numerical applications include the H-dibaryon, strange states and nucleon resonances. • The statistical point of view does not encourage the idea of bound many-quark baryons.

  5. Numerical approaches to combustion modeling

    SciTech Connect

    Oran, E.S.; Boris, J.P. )

    1991-01-01

    This book presents a series of topics ranging from microscopic combustion physics to several aspects of macroscopic reactive-flow modeling. As the reader progresses into the book, the successive chapters generally include a wider range of physical and chemical processes in the mathematical model. Including more processes, however, usually means that they will be represented phenomenologically at a cruder level. In practice the detailed microscopic models and simulations are often used to develop and calibrate the phenomenologies used in the macroscopic models. The book first describes computations of the most microscopic chemical processes, then considers laminar flames and detonation modeling, and ends with computations of complex, multiphase combustion systems.

  6. High Rayleigh number convection in rectangular enclosures with differentially heated vertical walls and aspect ratios between zero and unity

    NASA Technical Reports Server (NTRS)

    Kassemi, Siavash A.

    1988-01-01

    High Rayleigh number convection in a rectangular cavity with insulated horizontal surfaces and differentially heated vertical walls was analyzed for an arbitrary aspect ratio smaller than or equal to unity. Unlike previous analytical studies, a systematic method of solution based on linearization technique and analytical iteration procedure was developed to obtain approximate closed-form solutions for a wide range of aspect ratios. The predicted velocity and temperature fields are shown to be in excellent agreement with available experimental and numerical data.

  7. Granular Flow Dynamics on Earth, Moon, and Mars from analytical, numerical and field analysis

    NASA Astrophysics Data System (ADS)

    Lucas, A.; Mangeney, A.; Mhge, D.

    2010-12-01

    Prediction of landslides dynamics remains difficult in spite of a considerable body of work. A number of previous studies have been based on runout analysis in relation to mean dissipation calibration via the friction coefficient. However, the shape of the initial scar is generally unknown in real cases, which weakens landslide material spreading predictions and has alters calibration parameters of numerical models. We study numerically the effects of scar geometry on flow and distribution of the deposits and show that the initial shape of the scar, independent of the friction coefficient, does not affect the runout distance. In contrast, 3D tests show that the shape of the final deposits is a function of the scar geometry, and hence information on initial scar geometry and initial volume involved in the mass spreading may be retrieved from analysis of final deposit morphology. From an analytical solution we show here why the classical mobility (defined as the ratio between total height and runout distance) decreases when the volume increases, as is generally observed in geological data. We thus introduce analytically a new mobility variable obtained from geomorphic measurements reflecting the intrinsic dissipation independent of the aspect ratio, of the volume of the granular mass involved, of the underlying topography, and of the initial scar geometry. Comparison between experimental results, terrestrial, Lunar and Martian cases highlights a larger new mobility measure of natural granular flows compared to dry mass spreading simulated in the laboratory. In addition, landslides in a similar geological context give a single value showing the robustness of this new parameter. Finally, the new mobility provides a first order estimate of the effective friction required in models to reproduce the extent of the deposits in a given geological context. This enables a feedback analysis method for retrieving the volume and shape of the initial landslide material and then

  8. On current aspects of finite element computational fluid mechanics for turbulent flows

    NASA Technical Reports Server (NTRS)

    Baker, A. J.

    1982-01-01

    A set of nonlinear partial differential equations suitable for the description of a class of turbulent three-dimensional flow fields in select geometries is identified. On the basis of the concept of enforcing a penalty constraint to ensure accurate accounting of ordering effects, a finite element numerical solution algorithm is established for the equation set and the theoretical aspects of accuracy, convergence and stability are identified and quantized. Hypermatrix constructions are used to formulate the reduction of the computational aspects of the theory to practice. The robustness of the algorithm, and the computer program embodiment, have been verified for pertinent flow configurations.

  9. A hierarchical view of grounded, embodied, and situated numerical cognition.

    PubMed

    Fischer, Martin H

    2012-08-01

    There is much recent interest in the idea that we represent our knowledge together with the sensory and motor features that were activated during its acquisition. This paper reviews the evidence for such "embodiment" in the domain of numerical cognition, a traditional stronghold of abstract theories of knowledge representation. The focus is on spatial-numerical associations, such as the SNARC effect (small numbers are associated with left space, larger numbers with right space). Using empirical evidence from behavioral research, I first describe sensory and motor biases induced by SNARC, thus identifying numbers as embodied concepts. Next, I propose a hierarchical relationship between grounded, embodied, and situated aspects of number knowledge. This hierarchical conceptualization helps to understand the variety of SNARC-related findings and yields testable predictions about numerical cognition. I report several such tests, ranging from cross-cultural comparisons of horizontal and vertical SNARC effects (Shaki and Fischer in J Exp Psychol Hum Percept Perform 38(3):804-809, 2012) to motor cortical activation studies in adults with left- and right-hand counting preferences (Tschentscher et al. in NeuroImage 59:3139-3148, 2012). It is concluded that the diagnostic features for each level of the proposed hierarchical knowledge representation, together with the spatial associations of numbers, make the domain of numerical knowledge an ideal testing ground for embodied cognition research.

  10. An experimental and numerical study of boundary layer structure over areas of inhomogeneous sensible heat fluxes

    SciTech Connect

    Zhong, S.; Doran, J.C.

    1994-03-01

    In June of 1992 a boundary-layer experiment was carried out near Boardman, Oregon. The campaigns were part of a program of studies under the auspices of the US Department of Energy`s Atmospheric Radiation Measurement (ARM) program, whose goal is to improve the treatment of radiative transfer, particularly as affected by clouds, in general circulation models (GCMs) used for climate studies. One aspect of this program is concerned with the determination of appropriate lower boundary conditions for such models and the representation of subgrid-scale variability in regions where the surface conditions are not uniform. To study this problem, boundary-layer and surface properties were measured over a region of two sharply contrasting land types: a large, dry, sagebrush steppe area and irrigated farmland that formed the east, northeast, and western borders of the steppe. A combination of surface flux instrumentation, airsondes, sodars, and near-surface wind and temperature sensors was used. Measurements were carried out over the eastern portion of this region, which featured a well-defined boundary between the dry and irrigated areas. In this paper, the authors present some results from those observations and from a set of numerical simulations that address the effects of inhomogeneous surface fluxes on boundary-layer structure.

  11. A participatory modelling approach to developing a numerical sediment dynamics model

    NASA Astrophysics Data System (ADS)

    Jones, Nicholas; McEwen, Lindsey; Parker, Chris; Staddon, Chad

    2016-04-01

    Fluvial geomorphology is recognised as an important consideration in policy and legislation in the management of river catchments. Despite this recognition, limited knowledge exchange occurs between scientific researchers and river management practitioners. An example of this can be found within the limited uptake of numerical models of sediment dynamics by river management practitioners in the United Kingdom. The uptake of these models amongst the applied community is important as they have the potential to articulate how, at the catchment-scale, the impacts of management strategies of land-use change affect sediment dynamics and resulting channel quality. This paper describes and evaluates a new approach which involves river management stakeholders in an iterative and reflexive participatory modelling process. The aim of this approach was to create an environment for knowledge exchange between the stakeholders and the research team in the process of co-constructing a model. This process adopted a multiple case study approach, involving four groups of river catchment stakeholders in the United Kingdom. These stakeholder groups were involved in several stages of the participatory modelling process including: requirements analysis, model design, model development, and model evaluation. Stakeholders have provided input into a number of aspects of the modelling process, such as: data requirements, user interface, modelled processes, model assumptions, model applications, and model outputs. This paper will reflect on this process, in particular: the innovative methods used, data generated, and lessons learnt.

  12. Numerical and experimental study of strata behavior and land subsidence in an underground coal gasification project

    NASA Astrophysics Data System (ADS)

    Sirdesai, N. N.; Singh, R.; Singh, T. N.; Ranjith, P. G.

    2015-11-01

    Underground Coal Gasification, with enhanced knowledge of hydrogeological, geomechanical and environmental aspects, can be an alternative technique to exploit the existing unmineable reserves of coal. During the gasification process, petro-physical and geomechanical properties undergo a drastic change due to heating to elevated temperatures. These changes, caused due to the thermal anisotropy of various minerals, result in the generation of thermal stresses; thereby developing new fracture pattern. These fractures cause the overhead rock strata to cave and fill the gasification chamber thereby causing subsidence. The degree of subsidence, change in fluid transport and geomechanical properties of the rock strata, in and around the subsidence zone, can affect the groundwater flow. This study aims to predict the thermo-geomechanical response of the strata during UCG. Petro-physical and geomechanical properties are incorporated in the numerical modelling software COMSOL Multiphysics and an analytical strength model is developed to validate and further study the mechanical response and heat conduction of the host rock around the gasification chamber. Once the problems are investigated and solved, the enhanced efficiency and the economic exploitation of gasification process would help meet country's energy demand.

  13. A modified pseudoisochromatic ishihara colour vision test based on eastern arabic numerals.

    PubMed

    Heidary, Fatemeh; Gharebaghi, Reza

    2013-01-01

    Congenital colour vision defects affect about 8% and 0.5% of the male and female population, respectively. Pseudoisochromatic Ishihara plates have shown to be successful in an early diagnosis of colour vision defects. This commonly used colour vision test was initially intended to identify those who suffered from red-green aspect of congenital colour blindness; however, it may be of use to reveal acquired colour vision defects as well. Despite the Ishihara plates' value, there are a number of shortcomings in their current layout. We proposing a new colour plate modified from original Ishihara test. To best assist illiterates who are not able to read English, standard Ishihara plates have been translated to Eastern Arabic numerals, which are used in most parts of the Middle East, Central Asia and Africa populations. The purpose of the present modification was to present the new plates to these regions, but more research and study is required to work on the validity, reliability, and repeatability of these new plates.

  14. Numerical Study on plumes and thermochemical piles in plate-mode convection

    NASA Astrophysics Data System (ADS)

    Stein, C.; Brannaschke, K.; Hansen, U.

    2010-12-01

    Plates and plumes are two important aspects of mantle convection that both have large impact on the structure and dynamics of the Earth's mantle. Tectonic plates shield the interior from effective cooling and the movement of plates and subduction processes affect the dynamics of the interior. Thermal plumes and thermochemical piles forming at the core-mantle boundary play a further role in the mixing and evolution of the mantle. We apply a 2D numerical code to investigate the structure and evolution of the mantle in thermal and thermochemical convection. In our model plates form in a self-consistent manner, so that we can study the effect of plate-mode convection. During periods of subduction, we observe the formation of plume clusters. In cases where we apply a strong pressure-dependent viscosity, we find a few, stable Superplumes. In thermochemical convection dense material is viscously trapped by the flow and piled up beneath plumes. We will here discuss the effect of plates on plumes and piles and compare the signals they leave at the surface and core-mantle boundary.

  15. Design of motorcycle rider protection systems using numerical techniques.

    PubMed

    Miralbes, R

    2013-10-01

    The goal of this paper is the development of a design methodology, based on the use of finite elements numerical tools and dummies in order to study the damages and injuries that appear during a motorcyclist collision against a motorcyclist protection system (MPS). According to the existing regulation, a Hybrid III dummy FEM model has been used as a starting point and some modifications have been included. For instance a new finite element helmet model has been developed and later added to the dummy model. Moreover, some structural elements affecting the simulation results such as the connecting bolts or the ground have been adequately modeled. Finally there have been analyzed diverse types of current motorcyclists protection systems, for which it has been made a comparative numerical-experiment analysis to validate the numerical results and the methodology used.

  16. Design of motorcycle rider protection systems using numerical techniques.

    PubMed

    Miralbes, R

    2013-10-01

    The goal of this paper is the development of a design methodology, based on the use of finite elements numerical tools and dummies in order to study the damages and injuries that appear during a motorcyclist collision against a motorcyclist protection system (MPS). According to the existing regulation, a Hybrid III dummy FEM model has been used as a starting point and some modifications have been included. For instance a new finite element helmet model has been developed and later added to the dummy model. Moreover, some structural elements affecting the simulation results such as the connecting bolts or the ground have been adequately modeled. Finally there have been analyzed diverse types of current motorcyclists protection systems, for which it has been made a comparative numerical-experiment analysis to validate the numerical results and the methodology used. PMID:23792610

  17. Aspects concerning the quality of aeration for environmental friendly turbines

    NASA Astrophysics Data System (ADS)

    Bunea, F.; Houde, S.; Ciocan, G. D.; Oprina, G.; Baran, G.; Pincovschi, I.

    2010-08-01

    The hydro renewable energy provides a reliable power source; it does not pollute the air or land but affects the aquatic habitat due to low dissolved oxygen (DO) level in the water discharged from turbines. Hydro-turbines intake generally withdraws water from the bottom layer of the reservoirs with low DO level. In the different methods used for improving DO downstream the hydropower plants the volume of air is considered to be the main parameter of the injection. The energetic consumption is affected, in terms of loss of turbine efficiency due to air injection. The authors propose a study to show the importance of the quality of air injection, meaning bubble size, pressure loss on the aeration device etc. Different types of fine bubble aeration systems have been tested and compared. The capacity to predict the aeration by numerical simulation is analysed.

  18. Computational Aspects of Data Assimilation and the ESMF

    NASA Technical Reports Server (NTRS)

    daSilva, A.

    2003-01-01

    The scientific challenge of developing advanced data assimilation applications is a daunting task. Independently developed components may have incompatible interfaces or may be written in different computer languages. The high-performance computer (HPC) platforms required by numerically intensive Earth system applications are complex, varied, rapidly evolving and multi-part systems themselves. Since the market for high-end platforms is relatively small, there is little robust middleware available to buffer the modeler from the difficulties of HPC programming. To complicate matters further, the collaborations required to develop large Earth system applications often span initiatives, institutions and agencies, involve geoscience, software engineering, and computer science communities, and cross national borders.The Earth System Modeling Framework (ESMF) project is a concerted response to these challenges. Its goal is to increase software reuse, interoperability, ease of use and performance in Earth system models through the use of a common software framework, developed in an open manner by leaders in the modeling community. The ESMF addresses the technical and to some extent the cultural - aspects of Earth system modeling, laying the groundwork for addressing the more difficult scientific aspects, such as the physical compatibility of components, in the future. In this talk we will discuss the general philosophy and architecture of the ESMF, focussing on those capabilities useful for developing advanced data assimilation applications.

  19. Evaluation of environmental aspects significance in ISO 14001.

    PubMed

    Põder, Tõnis

    2006-05-01

    The methodological framework set by standards ISO 14001 and ISO 14004 gives only general principles for environmental aspects assessment, which is regarded as one of the most critical stages of implementing environmental management system. In Estonia, about 100 organizations have been certified to the ISO 14001. Experience obtained from numerous companies has demonstrated that limited transparency and reproducibility of the assessment process serves as a common shortcoming. Despite rather complicated assessment schemes sometimes used, the evaluation procedures have been largely based on subjective judgments because of ill-defined and inadequate assessment criteria. A comparison with some similar studies in other countries indicates a general nature of observed inconsistencies. The diversity of approaches to the aspects' assessment in concept literature and to the related problems has been discussed. The general structure of basic assessment criteria, compatible with environmental impact assessment and environmental risk analysis has also been outlined. Based on this general structure, the article presents a tiered approach to help organize the assessment in a more consistent manner.

  20. Drama and the Representation of Affect--Structures of Feeling and Signs of Learning

    ERIC Educational Resources Information Center

    Franks, Anton

    2014-01-01

    The way in which school students represent affective aspects of human relationships in drama and what this reveals about learning in drama is the focus of this paper. Such an enquiry traverses the borders between affect, intellect, and physicality. Affect and its representation in drama have been themes in the history of drama and theatre and is a…