Sample records for half-population issledovanie modeli

  1. Fast half-sibling population reconstruction: theory and algorithms.

    PubMed

    Dexter, Daniel; Brown, Daniel G

    2013-07-12

    Kinship inference is the task of identifying genealogically related individuals. Kinship information is important for determining mating structures, notably in endangered populations. Although many solutions exist for reconstructing full sibling relationships, few exist for half-siblings. We consider the problem of determining whether a proposed half-sibling population reconstruction is valid under Mendelian inheritance assumptions. We show that this problem is NP-complete and provide a 0/1 integer program that identifies the minimum number of individuals that must be removed from a population in order for the reconstruction to become valid. We also present SibJoin, a heuristic-based clustering approach based on Mendelian genetics, which is strikingly fast. The software is available at http://github.com/ddexter/SibJoin.git+. Our SibJoin algorithm is reasonably accurate and thousands of times faster than existing algorithms. The heuristic is used to infer a half-sibling structure for a population which was, until recently, too large to evaluate.

  2. Characterizing Atacama B-mode Search Detectors with a Half-Wave Plate

    NASA Astrophysics Data System (ADS)

    Simon, S. M.; Appel, J. W.; Campusano, L. E.; Choi, S. K.; Crowley, K. T.; Essinger-Hileman, T.; Gallardo, P.; Ho, S. P.; Kusaka, A.; Nati, F.; Palma, G. A.; Page, L. A.; Raghunathan, S.; Staggs, S. T.

    2016-08-01

    The Atacama B-Mode Search (ABS) instrument is a cryogenic (˜ 10 K) crossed-Dragone telescope located at an elevation of 5190 m in the Atacama Desert in Chile that observed for three seasons between February 2012 and October 2014. ABS observed the cosmic microwave background (CMB) at large angular scales (40<ℓ <500) to limit the B-mode polarization spectrum around the primordial B-mode peak from inflationary gravity waves at ℓ ˜ 100. The ABS focal plane consists of 480 transition-edge sensor (TES) bolometers. They are coupled to orthogonal polarizations from a planar ortho-mode transducer and observe at 145 GHz. ABS employs an ambient-temperature, rapidly rotating half-wave plate (HWP) to mitigate systematic effects and move the signal band away from atmospheric 1 / f noise, allowing for the recovery of large angular scales. We discuss how the signal at the second harmonic of the HWP rotation frequency can be used for data selection and for monitoring the detector responsivities.

  3. Open-ended half-mode substrate integrated waveguide sensor with ground flange for complex permittivity measurement

    USDA-ARS?s Scientific Manuscript database

    A novel open-ended half-mode substrate integrated waveguide (HMSIW) sensor with ground flange for measuring complex permittivity of liquids, semisolids, and granular and particulate materials is presented. The open-ended HMSIW is designed and fabricated on FR4 substrate. The ground flange was custo...

  4. Family losses following truncation selection in populations of half-sib families

    Treesearch

    J. H. Roberds; G. Namkoong; H. Kang

    1980-01-01

    Family losses during truncation selection may be sizable in populations of half-sib families. Substantial losses may occur even in populations containing little or no variation among families. Heavier losses will occur, however, under conditions of high heritability where there is considerable family variation. Standard deviations and therefore variances of family loss...

  5. A Characteristic Mode Analysis of Conductive Nanowires and Microwires Above a Lossy Dielectric Half-Space

    NASA Astrophysics Data System (ADS)

    Kiddle, Daniel S.

    Nanowires possess extraordinary mechanical, thermoelectric and electromagnetic properties which led to their incorporation in a wide variety of applications. The purpose of this study is to investigate the effect of material on the electromagnetic response of these nanowires. We used the Method of Moments (MOM) for Arbitrarily Thin Wire (ATW) formulation as an efficient computational technique for calculating the electromagnetic response of nanowires. To explain the calculated electromagnetic response, we evoked the Characteristic Mode Analysis (CMA) which decomposes the current on the wire into a superposition of fundamental current modes. These modes are weighted by two coefficients: (i) the relative importance of each mode at a certain frequency, termed Modal Significance, and (ii) the level of coupling between the incident field and the mode termed the Modal Excitation Coefficient. In this, work we study how the wire's material affect the Modal Significance and the Modal Excitation Coefficient of nanowires. Our results show that the material of the nanowire has a strong effect on the resonance frequency, the bandwidth, and the overlap of the modes showing that the material of the nanowire can be used as a tuning factor to develop sensors with desired radiation characteristics. Nanowires are commonly grown vertically on a substrate and, therefore, we also study the effect of the presence of a lossy dielectric half-space on their electromagnetic response. To efficiently account for this interface, we utilize a modified Green's function using the rigorous Sommerfeld integrals. Our results show that the relative permittivity of the substrate decreases the resonance frequencies of the nanowires and significantly alters their radiation patterns. Most importantly, we find that, if the nanowire is near the interface, its evanescent field's couple to the dielectric half space leading to the majority of the scattered power radiated into the substrate with high

  6. Population of collective modes in light scattering by many atoms

    NASA Astrophysics Data System (ADS)

    Guerin, William; Kaiser, Robin

    2017-05-01

    The interaction of light with an atomic sample containing a large number of particles gives rise to many collective (or cooperative) effects, such as multiple scattering, superradiance, and subradiance, even if the atomic density is low and the incident optical intensity weak (linear optics regime). Tracing over the degrees of freedom of the light field, the system can be well described by an effective atomic Hamiltonian, which contains the light-mediated dipole-dipole interaction between atoms. This long-range interaction is at the origin of the various collective effects, or of collective excitation modes of the system. Even though an analysis of the eigenvalues and eigenfunctions of these collective modes does allow distinguishing superradiant modes, for instance, from other collective modes, this is not sufficient to understand the dynamics of a driven system, as not all collective modes are significantly populated. Here, we study how the excitation parameters, i.e., the driving field, determines the population of the collective modes. We investigate in particular the role of the laser detuning from the atomic transition, and demonstrate a simple relation between the detuning and the steady-state population of the modes. This relation allows understanding several properties of cooperative scattering, such as why superradiance and subradiance become independent of the detuning at large enough detuning without vanishing, and why superradiance, but not subradiance, is suppressed near resonance. We also show that the spatial properties of the collective modes allow distinguishing diffusive modes, responsible for radiation trapping, from subradiant modes.

  7. Cross correlation in the two-mode laser

    NASA Astrophysics Data System (ADS)

    Kennedy, T. A. B.; Swain, S.

    1984-11-01

    Thomas et al. proposed the generation of cross correlation between two laser fields interacting with a three-level system as a means of reducing noise and subsequently exploited this property in the observation of very narrow Ramsey fringes. Cross correlation has been discussed theoretically by Dalton and Knight and shown to have interesting effects in population trapping. For such effects to be important, the cross correlation coefficient must be as large as possible. The degree of correlation between the two modes of a two-mode laser is discussed using the approach of Scully and Lamb, and it is shown that it can be large. The linewidths of the two laser modes are evaluated. It is found that if the laser parameters for the two modes are equal, the two-mode linewidth is one half the value of the linewidth of the corresponding single-mode laser, well above threshold.

  8. Effect of Interaction on the Majorana Zero Modes in the Kitaev Chain at Half Filling

    NASA Astrophysics Data System (ADS)

    Li, Zhidan; Han, Qiang

    2018-04-01

    The one dimension interacting Kitaev chain at half filling is studied. The symmetry of the Hamiltonian is examined by dual transformations and various physical quantities as functions of the fermion-fermion interaction $U$ are calculated systematically using the density matrix renormalization group method. A special value of interaction $U_p$ is revealed in the topological region of the phase diagram. We show that at $U_p$ the ground states are strictly two-fold degenerate even though the chain length is finite and the zero-energy peak due to the Majorana zero modes is maximally enhanced and exactly localized at the end sites. $U_p$ may be attractive or repulsive depending on other system parameters. We also give a qualitative understanding of the effect of interaction under the self-consistent mean field framework.

  9. Magneto-thermal reconnection processes, related mode momentum and formation of high energy particle populations

    DOE PAGES

    Coppi, B.; Basu, B.; Fletcher, A.

    2017-05-31

    In the context of a two-fluid theory of magnetic reconnection, when the longitudinal electron thermal conductivity is relatively large, the perturbed electron temperature tends to become singular in the presence of a reconnected field component and an electron temperature gradient. A finite transverse thermal diffusivity removes this singularity while a finite ‘inductivity’ can remove the singularity of the relevant plasma displacement. Then (i) a new ‘magneto-thermal’ reconnection producing mode, is found with characteristic widths of the reconnection layer remaining significant even when the macroscopic distances involved are very large; (ii) the mode phase velocities can be both in the directionmore » of the electron diamagnetic velocity as well in the opposite (ion) direction. A numerical solution of the complete set of equations has been carried out with a simplified analytical reformulation of the problem. A sequence of processes is analyzed to point out that high-energy particle populations can be produced as a result of reconnection events. These processes involve mode-particle resonances transferring energy of the reconnecting mode to a superthermal ion population and the excitation of lower hybrid waves that can lead to a significant superthermal electron population. The same modes excited in axisymmetric (e.g. toroidal) confinement configurations can extract angular momentum from the main body of the plasma column and thereby sustain a local ‘spontaneous rotation’ of it.« less

  10. Linear bunchers and half-frequency bunching method

    NASA Astrophysics Data System (ADS)

    Tang, J. Y.; Jiang, J. Z.; Shi, A. M.; Yin, Z. K.; Wang, Y. F.

    2000-12-01

    A new buncher system consisting of two bunchers has been designed and constructed for HIRFL injector cyclotron, working at the SFC acceleration modes of H=1 and H=3, respectively. The bunchers use saw-tooth RF waveform, but with double-gap drift tube electrodes and single-gap grid electrodes, respectively. The special merit of the design is introduction of the half-frequency bunching mode, utilizing half of the cyclotron RF frequency. With this method, a perfect longitudinal match between the injector SFC and the main cyclotron SSC has been reached theoretically, compared to the original efficiency of 50% for most cases. Detailed studies have been made concerning space charge effects, longitudinal dispersions through the yoke hole and the spiral inflector, and non-linearity in both the RF waveform and the stray electric field of electrodes.

  11. Feeding modes in stream salmonid population models: Is drift feeding the whole story?

    Treesearch

    Bret Harvey; Steve Railsback

    2014-01-01

    Drift-feeding models are essential components of broader models that link stream habitat to salmonid populations and community dynamics. But is an additional feeding mode needed for understanding and predicting salmonid population responses to streamflow and other environmental factors? We addressed this question by applying two versions of the individual-based model...

  12. Observation of roton mode population in a dipolar quantum gas

    NASA Astrophysics Data System (ADS)

    Chomaz, L.; van Bijnen, R. M. W.; Petter, D.; Faraoni, G.; Baier, S.; Becher, J. H.; Mark, M. J.; Wächtler, F.; Santos, L.; Ferlaino, F.

    2018-05-01

    The concept of a roton, a special kind of elementary excitation forming a minimum of energy at finite momentum, has been essential for the understanding of the properties of superfluid 4He (ref. 1). In quantum liquids, rotons arise from the strong interparticle interactions, whose microscopic description remains debated2. In the realm of highly controllable quantum gases, a roton mode has been predicted to emerge due to magnetic dipole-dipole interactions despite their weakly interacting character3. This prospect has raised considerable interest4-12; yet roton modes in dipolar quantum gases have remained elusive to observations. Here we report experimental and theoretical studies of the momentum distribution in Bose-Einstein condensates of highly magnetic erbium atoms, revealing the existence of the long-sought roton mode. Following an interaction quench, the roton mode manifests itself with the appearance of symmetric peaks at well-defined finite momentum. The roton momentum follows the predicted geometrical scaling with the inverse of the confinement length along the magnetization axis. From the growth of the roton population, we probe the roton softening of the excitation spectrum in time and extract the corresponding imaginary roton gap. Our results provide a further step in the quest towards supersolidity in dipolar quantum gases13.

  13. All half-lives are wrong, but some half-lives are useful.

    PubMed

    Wright, J G; Boddy, A V

    2001-01-01

    The half-life of a drug, which expresses a change in concentration in units of time, is perhaps the most easily understood pharmacokinetic parameter and provides a succinct description of many concentration-time profiles. The calculation of a half-life implies a linear, first-order, time-invariant process. No drug perfectly obeys such assumptions, although in practise this is often a valid approximation and provides invaluable quantitative information. Nevertheless, the physiological processes underlying half-life should not be forgotten. The concept of clearance facilitates the interpretation of factors affecting drug elimination, such as enzyme inhibition or renal impairment. Relating clearance to the observed concentration-time profile is not as naturally intuitive as is the case with half-life. As such, these 2 approaches to parameterising a linear pharmacokinetic model should be viewed as complementary rather than alternatives. The interpretation of pharmacokinetic parameters when there are multiple disposition phases is more challenging. Indeed, in any pharmacokinetic model, the half-lives are only one component of the parameters required to specify the concentration-time profile. Furthermore, pharmacokinetic parameters are of little use without a dose history. Other factors influencing the relevance of each disposition phase to clinical end-points must also be considered. In summarising the pharmacokinetics of a drug, statistical aspects of the estimation of a half-life are often overlooked. Half-lives are rarely reported with confidence intervals or measures of variability in the population, and some approaches to this problem are suggested. Half-life is an important summary statistic in pharmacokinetics, but care must be taken to employ it appropriately in the context of dose history and clinically relevant pharmacodynamic end-points.

  14. Frequency regularities of acoustic modes and multi-colour mode identification in rapidly rotating stars

    NASA Astrophysics Data System (ADS)

    Reese, D. R.; Lignières, F.; Ballot, J.; Dupret, M.-A.; Barban, C.; van't Veer-Menneret, C.; MacGregor, K. B.

    2017-05-01

    Context. Mode identification has remained a major obstacle in the interpretation of pulsation spectra in rapidly rotating stars. This has motivated recent work on calculating realistic multi-colour mode visibilities in this type of star. Aims: We would like to test mode identification methods and seismic diagnostics in rapidly rotating stars, using oscillation spectra that are based on these new theoretical predictions. Methods: We investigate the auto-correlation function and Fourier transform of theoretically calculated frequency spectra, in which modes are selected according to their visibilities. Given that intrinsic mode amplitudes are determined by non-linear saturation and cannot currently be theoretically predicted, we experimented with various ad-hoc prescriptions for setting the mode amplitudes, including using random values. Furthermore, we analyse the ratios between mode amplitudes observed in different photometric bands to see up to what extent they can identify modes. Results: When non-random intrinsic mode amplitudes are used, our results show that it is possible to extract a mean value for the large frequency separation or half its value and, sometimes, twice the rotation rate, from the auto-correlation of the frequency spectra. Furthermore, the Fourier transforms are mostly sensitive to the large frequency separation or half its value. The combination of the two methods may therefore measure and distinguish the two types of separations. When the intrinsic mode amplitudes include random factors, which seems more representative of real stars, the results are far less favourable. It is only when the large separation or half its value coincides with twice the rotation rate, that it might be possible to detect the signature of a frequency regularity. We also find that amplitude ratios are a good way of grouping together modes with similar characteristics. By analysing the frequencies of these groups, it is possible to constrain mode identification, as

  15. Detection and characterization of nonspecific, sparsely-populated binding modes in the early stages of complexation

    PubMed Central

    Cardone, A.; Bornstein, A.; Pant, H. C.; Brady, M.; Sriram, R.; Hassan, S. A.

    2015-01-01

    A method is proposed to study protein-ligand binding in a system governed by specific and non-specific interactions. Strong associations lead to narrow distributions in the proteins configuration space; weak and ultra-weak associations lead instead to broader distributions, a manifestation of non-specific, sparsely-populated binding modes with multiple interfaces. The method is based on the notion that a discrete set of preferential first-encounter modes are metastable states from which stable (pre-relaxation) complexes at equilibrium evolve. The method can be used to explore alternative pathways of complexation with statistical significance and can be integrated into a general algorithm to study protein interaction networks. The method is applied to a peptide-protein complex. The peptide adopts several low-population conformers and binds in a variety of modes with a broad range of affinities. The system is thus well suited to analyze general features of binding, including conformational selection, multiplicity of binding modes, and nonspecific interactions, and to illustrate how the method can be applied to study these problems systematically. The equilibrium distributions can be used to generate biasing functions for simulations of multiprotein systems from which bulk thermodynamic quantities can be calculated. PMID:25782918

  16. Abortion rate during the second half of gestation of cows undergoing surgery in lateral recumbency as compared with cows of a control population.

    PubMed

    Hirsbrunner, G; Knutti, B; Eicher, R

    1999-01-01

    In a retrospective study, we compared the abortion rates of 59 cows in the second half of gestation, admitted to the Clinic for Food Animals and Horses (1993-1996) with a strictly focal problem (head region, udder and teats, locomotor system) requiring surgery in lateral recumbency, to the abortion rate of a control cow population. Before surgery, a uterus relaxant was given in 42 cases, and 17 cows were untreated as to pregnancy. Cows included in the reproduction health program of the Department of Fertility and Reproduction were used as a control population. Data of 1,736 cows pregnant in the second half of gestation per year were available for the same time period (1993-1996). Abortion rate was 5.08% for the cows undergoing surgery in lateral recumbency as compared with 5.18% for the cows of the control population. There was no significant difference between the two populations (P > 0.05). Thus, the risk for abortion in the cows in question is not elevated as compared with the control population.

  17. Time-frequency analysis of neuronal populations with instantaneous resolution based on noise-assisted multivariate empirical mode decomposition.

    PubMed

    Alegre-Cortés, J; Soto-Sánchez, C; Pizá, Á G; Albarracín, A L; Farfán, F D; Felice, C J; Fernández, E

    2016-07-15

    Linear analysis has classically provided powerful tools for understanding the behavior of neural populations, but the neuron responses to real-world stimulation are nonlinear under some conditions, and many neuronal components demonstrate strong nonlinear behavior. In spite of this, temporal and frequency dynamics of neural populations to sensory stimulation have been usually analyzed with linear approaches. In this paper, we propose the use of Noise-Assisted Multivariate Empirical Mode Decomposition (NA-MEMD), a data-driven template-free algorithm, plus the Hilbert transform as a suitable tool for analyzing population oscillatory dynamics in a multi-dimensional space with instantaneous frequency (IF) resolution. The proposed approach was able to extract oscillatory information of neurophysiological data of deep vibrissal nerve and visual cortex multiunit recordings that were not evidenced using linear approaches with fixed bases such as the Fourier analysis. Texture discrimination analysis performance was increased when Noise-Assisted Multivariate Empirical Mode plus Hilbert transform was implemented, compared to linear techniques. Cortical oscillatory population activity was analyzed with precise time-frequency resolution. Similarly, NA-MEMD provided increased time-frequency resolution of cortical oscillatory population activity. Noise-Assisted Multivariate Empirical Mode Decomposition plus Hilbert transform is an improved method to analyze neuronal population oscillatory dynamics overcoming linear and stationary assumptions of classical methods. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Rayleigh-type waves in nonlocal micropolar solid half-space.

    PubMed

    Khurana, Aarti; Tomar, S K

    2017-01-01

    Propagation of Rayleigh type surface waves in nonlocal micropolar elastic solid half-space has been investigated. Two modes of Rayleigh-type waves are found to propagate under certain approximations. Frequency equations of these Rayleigh type modes and their conditions of existence have been derived. These frequency equations are found to be dispersive in character due to the presence of micropolarity and nonlocality parameters in the medium. One of the frequency equations is a counterpart of the classical Rayleigh waves and the other is new and has appeared due to micropolarity of the medium. Phase speeds of these waves are computed numerically for Magnesium crystal and their variation against wavenumber are presented graphically. Comparisons have been made between the phase speeds of Rayleigh type waves through nonlocal micropolar, local micropolar and elastic solid half-spaces. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Comparison of mode estimation methods and application in molecular clock analysis

    NASA Technical Reports Server (NTRS)

    Hedges, S. Blair; Shah, Prachi

    2003-01-01

    BACKGROUND: Distributions of time estimates in molecular clock studies are sometimes skewed or contain outliers. In those cases, the mode is a better estimator of the overall time of divergence than the mean or median. However, different methods are available for estimating the mode. We compared these methods in simulations to determine their strengths and weaknesses and further assessed their performance when applied to real data sets from a molecular clock study. RESULTS: We found that the half-range mode and robust parametric mode methods have a lower bias than other mode methods under a diversity of conditions. However, the half-range mode suffers from a relatively high variance and the robust parametric mode is more susceptible to bias by outliers. We determined that bootstrapping reduces the variance of both mode estimators. Application of the different methods to real data sets yielded results that were concordant with the simulations. CONCLUSION: Because the half-range mode is a simple and fast method, and produced less bias overall in our simulations, we recommend the bootstrapped version of it as a general-purpose mode estimator and suggest a bootstrap method for obtaining the standard error and 95% confidence interval of the mode.

  20. Mode Equivalence of Health Indicators Between Data Collection Modes and Mixed-Mode Survey Designs in Population-Based Health Interview Surveys for Children and Adolescents: Methodological Study

    PubMed Central

    Hoffmann, Robert; Houben, Robin; Krause, Laura; Kamtsiuris, Panagiotis; Gößwald, Antje

    2018-01-01

    Background The implementation of an Internet option in an existing public health interview survey using a mixed-mode design is attractive because of lower costs and faster data availability. Additionally, mixed-mode surveys can increase response rates and improve sample composition. However, mixed-mode designs can increase the risk of measurement error (mode effects). Objective This study aimed to determine whether the prevalence rates or mean values of self- and parent-reported health indicators for children and adolescents aged 0-17 years differ between self-administered paper-based questionnaires (SAQ-paper) and self-administered Web-based questionnaires (SAQ-Web), as well as between a single-mode control group and different mixed-mode groups. Methods Data were collected for a methodological pilot of the third wave of the "German Health Interview and Examination Survey for Children and Adolescents". Questionnaires were completed by parents or adolescents. A population-based sample of 11,140 children and adolescents aged 0-17 years was randomly allocated to 4 survey designs—a single-mode control group with paper-and-pencil questionnaires only (n=970 parents, n=343 adolescents)—and 3 mixed-mode designs, all of which offered Web-based questionnaire options. In the concurrent mixed-mode design, both questionnaires were offered at the same time (n=946 parents, n=290 adolescents); in the sequential mixed-mode design, the SAQ-Web was sent first, followed by the paper questionnaire along with a reminder (n=854 parents, n=269 adolescents); and in the preselect mixed-mode design, both options were offered and the respondents were asked to request the desired type of questionnaire (n=698 parents, n=292 adolescents). In total, 3468 questionnaires of parents of children aged 0-17 years (SAQ-Web: n=708; SAQ-paper: n=2760) and 1194 questionnaires of adolescents aged 11-17 years (SAQ-Web: n=299; SAQ-paper: n=895) were analyzed. Sociodemographic characteristics and a broad

  1. Mixing modes in a population-based interview survey: comparison of a sequential and a concurrent mixed-mode design for public health research.

    PubMed

    Mauz, Elvira; von der Lippe, Elena; Allen, Jennifer; Schilling, Ralph; Müters, Stephan; Hoebel, Jens; Schmich, Patrick; Wetzstein, Matthias; Kamtsiuris, Panagiotis; Lange, Cornelia

    2018-01-01

    Population-based surveys currently face the problem of decreasing response rates. Mixed-mode designs are now being implemented more often to account for this, to improve sample composition and to reduce overall costs. This study examines whether a concurrent or sequential mixed-mode design achieves better results on a number of indicators of survey quality. Data were obtained from a population-based health interview survey of adults in Germany that was conducted as a methodological pilot study as part of the German Health Update (GEDA). Participants were randomly allocated to one of two surveys; each of the surveys had a different design. In the concurrent mixed-mode design ( n  = 617) two types of self-administered questionnaires (SAQ-Web and SAQ-Paper) and computer-assisted telephone interviewing were offered simultaneously to the respondents along with the invitation to participate. In the sequential mixed-mode design ( n  = 561), SAQ-Web was initially provided, followed by SAQ-Paper, with an option for a telephone interview being sent out together with the reminders at a later date. Finally, this study compared the response rates, sample composition, health indicators, item non-response, the scope of fieldwork and the costs of both designs. No systematic differences were identified between the two mixed-mode designs in terms of response rates, the socio-demographic characteristics of the achieved samples, or the prevalence rates of the health indicators under study. The sequential design gained a higher rate of online respondents. Very few telephone interviews were conducted for either design. With regard to data quality, the sequential design (which had more online respondents) showed less item non-response. There were minor differences between the designs in terms of their costs. Postage and printing costs were lower in the concurrent design, but labour costs were lower in the sequential design. No differences in health indicators were found between

  2. Causality analysis of leading singular value decomposition modes identifies rotor as the dominant driving normal mode in fibrillation

    NASA Astrophysics Data System (ADS)

    Biton, Yaacov; Rabinovitch, Avinoam; Braunstein, Doron; Aviram, Ira; Campbell, Katherine; Mironov, Sergey; Herron, Todd; Jalife, José; Berenfeld, Omer

    2018-01-01

    Cardiac fibrillation is a major clinical and societal burden. Rotors may drive fibrillation in many cases, but their role and patterns are often masked by complex propagation. We used Singular Value Decomposition (SVD), which ranks patterns of activation hierarchically, together with Wiener-Granger causality analysis (WGCA), which analyses direction of information among observations, to investigate the role of rotors in cardiac fibrillation. We hypothesized that combining SVD analysis with WGCA should reveal whether rotor activity is the dominant driving force of fibrillation even in cases of high complexity. Optical mapping experiments were conducted in neonatal rat cardiomyocyte monolayers (diameter, 35 mm), which were genetically modified to overexpress the delayed rectifier K+ channel IKr only in one half of the monolayer. Such monolayers have been shown previously to sustain fast rotors confined to the IKr overexpressing half and driving fibrillatory-like activity in the other half. SVD analysis of the optical mapping movies revealed a hierarchical pattern in which the primary modes corresponded to rotor activity in the IKr overexpressing region and the secondary modes corresponded to fibrillatory activity elsewhere. We then applied WGCA to evaluate the directionality of influence between modes in the entire monolayer using clear and noisy movies of activity. We demonstrated that the rotor modes influence the secondary fibrillatory modes, but influence was detected also in the opposite direction. To more specifically delineate the role of the rotor in fibrillation, we decomposed separately the respective SVD modes of the rotor and fibrillatory domains. In this case, WGCA yielded more information from the rotor to the fibrillatory domains than in the opposite direction. In conclusion, SVD analysis reveals that rotors can be the dominant modes of an experimental model of fibrillation. Wiener-Granger causality on modes of the rotor domains confirms their

  3. Mode Equivalence of Health Indicators Between Data Collection Modes and Mixed-Mode Survey Designs in Population-Based Health Interview Surveys for Children and Adolescents: Methodological Study.

    PubMed

    Mauz, Elvira; Hoffmann, Robert; Houben, Robin; Krause, Laura; Kamtsiuris, Panagiotis; Gößwald, Antje

    2018-03-05

    The implementation of an Internet option in an existing public health interview survey using a mixed-mode design is attractive because of lower costs and faster data availability. Additionally, mixed-mode surveys can increase response rates and improve sample composition. However, mixed-mode designs can increase the risk of measurement error (mode effects). This study aimed to determine whether the prevalence rates or mean values of self- and parent-reported health indicators for children and adolescents aged 0-17 years differ between self-administered paper-based questionnaires (SAQ-paper) and self-administered Web-based questionnaires (SAQ-Web), as well as between a single-mode control group and different mixed-mode groups. Data were collected for a methodological pilot of the third wave of the "German Health Interview and Examination Survey for Children and Adolescents". Questionnaires were completed by parents or adolescents. A population-based sample of 11,140 children and adolescents aged 0-17 years was randomly allocated to 4 survey designs-a single-mode control group with paper-and-pencil questionnaires only (n=970 parents, n=343 adolescents)-and 3 mixed-mode designs, all of which offered Web-based questionnaire options. In the concurrent mixed-mode design, both questionnaires were offered at the same time (n=946 parents, n=290 adolescents); in the sequential mixed-mode design, the SAQ-Web was sent first, followed by the paper questionnaire along with a reminder (n=854 parents, n=269 adolescents); and in the preselect mixed-mode design, both options were offered and the respondents were asked to request the desired type of questionnaire (n=698 parents, n=292 adolescents). In total, 3468 questionnaires of parents of children aged 0-17 years (SAQ-Web: n=708; SAQ-paper: n=2760) and 1194 questionnaires of adolescents aged 11-17 years (SAQ-Web: n=299; SAQ-paper: n=895) were analyzed. Sociodemographic characteristics and a broad range of health indicators for

  4. Modulation of cosmic microwave background polarization with a warm rapidly rotating half-wave plate on the Atacama B-Mode Search instrument.

    PubMed

    Kusaka, A; Essinger-Hileman, T; Appel, J W; Gallardo, P; Irwin, K D; Jarosik, N; Nolta, M R; Page, L A; Parker, L P; Raghunathan, S; Sievers, J L; Simon, S M; Staggs, S T; Visnjic, K

    2014-02-01

    We evaluate the modulation of cosmic microwave background polarization using a rapidly rotating, half-wave plate (HWP) on the Atacama B-Mode Search. After demodulating the time-ordered-data (TOD), we find a significant reduction of atmospheric fluctuations. The demodulated TOD is stable on time scales of 500-1000 s, corresponding to frequencies of 1-2 mHz. This facilitates recovery of cosmological information at large angular scales, which are typically available only from balloon-borne or satellite experiments. This technique also achieves a sensitive measurement of celestial polarization without differencing the TOD of paired detectors sensitive to two orthogonal linear polarizations. This is the first demonstration of the ability to remove atmospheric contamination at these levels from a ground-based platform using a rapidly rotating HWP.

  5. Clumpak: a program for identifying clustering modes and packaging population structure inferences across K.

    PubMed

    Kopelman, Naama M; Mayzel, Jonathan; Jakobsson, Mattias; Rosenberg, Noah A; Mayrose, Itay

    2015-09-01

    The identification of the genetic structure of populations from multilocus genotype data has become a central component of modern population-genetic data analysis. Application of model-based clustering programs often entails a number of steps, in which the user considers different modelling assumptions, compares results across different predetermined values of the number of assumed clusters (a parameter typically denoted K), examines multiple independent runs for each fixed value of K, and distinguishes among runs belonging to substantially distinct clustering solutions. Here, we present Clumpak (Cluster Markov Packager Across K), a method that automates the postprocessing of results of model-based population structure analyses. For analysing multiple independent runs at a single K value, Clumpak identifies sets of highly similar runs, separating distinct groups of runs that represent distinct modes in the space of possible solutions. This procedure, which generates a consensus solution for each distinct mode, is performed by the use of a Markov clustering algorithm that relies on a similarity matrix between replicate runs, as computed by the software Clumpp. Next, Clumpak identifies an optimal alignment of inferred clusters across different values of K, extending a similar approach implemented for a fixed K in Clumpp and simplifying the comparison of clustering results across different K values. Clumpak incorporates additional features, such as implementations of methods for choosing K and comparing solutions obtained by different programs, models, or data subsets. Clumpak, available at http://clumpak.tau.ac.il, simplifies the use of model-based analyses of population structure in population genetics and molecular ecology. © 2015 John Wiley & Sons Ltd.

  6. Optimization of S/B in the detection of nuclear fission signatures via different accelerator pulsing modes

    NASA Astrophysics Data System (ADS)

    Brown, C.; Gozani, T.; Shaw, T.; Stevenson, J.

    2011-10-01

    In the search for concealed special nuclear materials (SNM) there are a number of fission specific signatures that can be measured. These include prompt and delayed neutron and gamma ray signatures. Here the focus will be on the delayed gamma signature with the assumption that a pulsed electron linac with a constant peak current will be used to generate bremsstrahlung radiation and induce photofission in 235U. In this case, the signal to background ratio (S/B) will depend on the choice of linac frequency, pulse mode, and "active" background due to linac activation products. The linac frequency is simply the rate at which it produces short bursts of radiation, typically 2-4 μs in duration. There are two pulse modes, micro-pulsing, and macro-pulsing. In the micro-pulsing mode, the linac runs continuously at its set frequency and data is collected between bursts. In the macro-pulsing mode, the linac is turned on for a given length of time, on the order of seconds, and then turned off for a period of time typically equal to the length of time it was turned on. Counting takes place during the time the linac is off and stops when the linac is turned on for another cycle. The time dependence of the delayed gamma population can be approximated by the use of 5 time groups with half-lives of 0.29, 1.7, 13, 100, and 940 s, respectively. Each group has its own relative population, which together with its half-life determines what time frame the group contributes most to the measured signal. For example, a group with a short half-life will contribute more signal to a short cycle macro pulsed measurement than it would to a macro pulse measurement with a very long cycle. An analytical expression can be derived that calculates the maximum obtainable signal (delayed gamma photons per fission gamma ray) in either a micro- or macro-pulsed measurement. Using this information along with the observed active background present in a given situation (which can constrain the micro

  7. Identification of g-Modes in a Sun with Mixed Core

    NASA Technical Reports Server (NTRS)

    Wolff, Charles L.

    2008-01-01

    The elusive g-mode oscillations mainly operate deep inside the Sun where the nuclear fires burn. They can modify the Sun's output on a cadence of months and years when coupled into groups. Scientists have failed to detect their oscillation periods because they were looking for periods much too short. This paper shows that if g-modes slowly mix the central 16% of the Sun on a million year time scale or less, then g-mode periods become two and a half times longer. These longer periods are identified in existing data from the orbiting GOLF and SOH0 experiments. This opens the door to measuring the Sun's central regions with g-modes just as helioseismology has used sound waves to probe its outer half.

  8. Recovering the negative mode for type B Coleman-de Luccia instantons

    NASA Astrophysics Data System (ADS)

    Yang, I.-Sheng

    2013-04-01

    The usual (type A) thin-wall Coleman—de Luccia instanton is made by a bigger-than-half sphere of the false vacuum and a smaller-than-half sphere of the true vacuum. It has the standard O(4) symmetric negative mode associated with changing the size of the true vacuum region. On the other hand, the type B instanton, made by two smaller-than-half spheres, was believed to have lost this negative mode. We argue that such a belief is misguided due to an overrestriction on the Euclidean path integral. We introduce the idea of a “purely geometric junction” to visualize why such a restriction could be removed, and then we explicitly construct this negative mode. We also show that type B and type A instantons have the same thermal interpretation for mediating tunnelings.

  9. LP01 to LP11 mode convertor based on side-polished small-core single-mode fiber

    NASA Astrophysics Data System (ADS)

    Liu, Yan; Li, Yang; Li, Wei-dong

    2018-03-01

    An all-fiber LP01-LP11 mode convertor based on side-polished small-core single-mode fibers (SMFs) is numerically demonstrated. The linearly polarized incident beam in one arm experiences π shift through a fiber half waveplate, and the side-polished parts merge into an equivalent twin-core fiber (TCF) which spatially shapes the incident LP01 modes to the LP11 mode supported by the step-index few-mode fiber (FMF). Optimum conditions for the highest conversion efficiency are investigated using the beam propagation method (BPM) with an approximate efficiency as high as 96.7%. The proposed scheme can operate within a wide wavelength range from 1.3 μm to1.7 μm with overall conversion efficiency greater than 95%. The effective mode area and coupling loss are also characterized in detail by finite element method (FEM).

  10. Helicon modes in uniform plasmas. I. Low m modes

    NASA Astrophysics Data System (ADS)

    Urrutia, J. M.; Stenzel, R. L.

    2015-09-01

    Helicons are whistler modes with azimuthal wave numbers. They arise in bounded gaseous and solid state plasmas, but the present work shows that very similar modes also exist in unbounded uniform plasmas. The antenna properties determine the mode structure. A simple antenna is a magnetic loop with dipole moment aligned either along or across the ambient background magnetic field B0. For such configurations, the wave magnetic field has been measured in space and time in a large and uniform laboratory plasma. The observed wave topology for a dipole along B0 is similar to that of an m = 0 helicon mode. It consists of a sequence of alternating whistler vortices. For a dipole across B0, an m = 1 mode is excited which can be considered as a transverse vortex which rotates around B0. In m = 0 modes, the field lines are confined to each half-wavelength vortex while for m = 1 modes they pass through the entire wave train. A subset of m = 1 field lines forms two nested helices which rotate in space and time like corkscrews. Depending on the type of the antenna, both m = + 1 and m = -1 modes can be excited. Helicons in unbounded plasmas also propagate transverse to B0. The transverse and parallel wave numbers are about equal and form oblique phase fronts as in whistler Gendrin modes. By superimposing small amplitude fields of several loop antennas, various antenna combinations have been created. These include rotating field antennas, helical antennas, and directional antennas. The radiation efficiency is quantified by the radiation resistance. Since helicons exist in unbounded laboratory plasmas, they can also arise in space plasmas.

  11. Half-and-Half Palatoplasty.

    PubMed

    Han, Hyun Ho; Kang, In Sook; Rhie, Jong Won

    2014-08-01

    A 14-month-old child was diagnosed with a Veau Class II cleft palate. Von Langenbeck palatoplasty was performed for the right palate, and V-Y pushback palatoplasty was performed for the left palate. The child did not have a special problem during the surgery, and the authors were able to elongate the cleft by 10 mm. Contrary to preoperative concerns regarding the hybrid use of palatoplasties, the uvula and midline incisions remained balanced in the middle. The authors named this combination method "half-and-half palatoplasty" and plan to conduct a long-term follow up study as a potential solution that minimizes the complications of palatoplasty.

  12. Half-and-Half Palatoplasty

    PubMed Central

    Han, Hyun Ho; Kang, In Sook

    2014-01-01

    A 14-month-old child was diagnosed with a Veau Class II cleft palate. Von Langenbeck palatoplasty was performed for the right palate, and V-Y pushback palatoplasty was performed for the left palate. The child did not have a special problem during the surgery, and the authors were able to elongate the cleft by 10 mm. Contrary to preoperative concerns regarding the hybrid use of palatoplasties, the uvula and midline incisions remained balanced in the middle. The authors named this combination method "half-and-half palatoplasty" and plan to conduct a long-term follow up study as a potential solution that minimizes the complications of palatoplasty. PMID:28913201

  13. The impact of new transportation modes on population distribution in Jing-Jin-Ji region of China

    PubMed Central

    Wang, Lizhe; Chen, Lajiao

    2018-01-01

    This paper conducts a novel study in China’s Jing-Jin-Ji region to investigate the determinants of population distribution and short-term migration based on a comprehensive dataset including traditional census data, earth observation data, and emerging Internet data. Our results show that due to the high level of urbanization in this region, natural conditions are no longer the strongest determinants of population distribution. New transportation modes, such as high-speed rail, have arisen as a significant determinant of population distribution and short-term migration, particularly in large cities. Socio-economic factors such as GDP, investment, urbanization level, and technology, which are traditionally assumed to govern population distribution and short-term migration, have less influence although education still remains an important factor affecting population distribution. These findings will contribute valuable information to regional planning decision-making in the Jing-Jin-Ji region. PMID:29360105

  14. Monoclonal antibody fragment removal mediated by mixed mode resins.

    PubMed

    O'Connor, Ellen; Aspelund, Matthew; Bartnik, Frank; Berge, Mark; Coughlin, Kelly; Kambarami, Mutsa; Spencer, David; Yan, Huiming; Wang, William

    2017-05-26

    Efforts to increase monoclonal antibody expression in cell culture can result in the presence of fragmented species requiring removal in downstream processing. Capto adhere, HEA Hypercel, and PPA Hypercel anion exchange/hydrophobic interaction mixed mode resins were evaluated for their fragment removal capabilities and found to separate large hinge IgG1 antibody fragment (LHF) from monomer. Removal of greater than 75% of LHF population occurred at pH 8 and low conductivity. The mechanism of fragment removal was investigated in two series of experiments. The first experimental series consisted of comparison to chromatographic behavior on corresponding single mode resins. Both single mode anion exchange and hydrophobic interaction resins failed to separate LHF. The second experimental series studied the impact of phase modifiers, ethylene glycol, urea, and arginine on the mixed mode mediated removal. The addition of ethylene glycol decreased LHF removal by half. Further decreases in LHF separation were seen upon incubation with urea and arginine. Therefore, it was discovered that the purification is the result of a mixed mode phenomena dominated by hydrophobic interaction and hydrogen bonding effects. The site of interaction between the LHF and mixed mode resin was determined by chemical labeling of lysine residues with sulfo-NHS acetate. The labeling identified the antibody hinge and light chain regions as mediating the fragment separation. Sequence analysis showed that under separation conditions, a hydrophobic proline patch and hydrogen bonding serine and threonine residues mediate the hinge interaction with the Capto adhere ligand. Additionally, a case study is presented detailing the optimization of fragment removal using Capto adhere resin to achieve purity and yield targets in a manufacturing facility. This study demonstrated that mixed mode resins can be readily integrated into commercial antibody platform processes when additional chromatographic abilities

  15. Mixed-mode oscillations and population bursting in the pre-Bötzinger complex

    PubMed Central

    Bacak, Bartholomew J; Kim, Taegyo; Smith, Jeffrey C; Rubin, Jonathan E; Rybak, Ilya A

    2016-01-01

    This study focuses on computational and theoretical investigations of neuronal activity arising in the pre-Bötzinger complex (pre-BötC), a medullary region generating the inspiratory phase of breathing in mammals. A progressive increase of neuronal excitability in medullary slices containing the pre-BötC produces mixed-mode oscillations (MMOs) characterized by large amplitude population bursts alternating with a series of small amplitude bursts. Using two different computational models, we demonstrate that MMOs emerge within a heterogeneous excitatory neural network because of progressive neuronal recruitment and synchronization. The MMO pattern depends on the distributed neuronal excitability, the density and weights of network interconnections, and the cellular properties underlying endogenous bursting. Critically, the latter should provide a reduction of spiking frequency within neuronal bursts with increasing burst frequency and a dependence of the after-burst recovery period on burst amplitude. Our study highlights a novel mechanism by which heterogeneity naturally leads to complex dynamics in rhythmic neuronal populations. DOI: http://dx.doi.org/10.7554/eLife.13403.001 PMID:26974345

  16. 21 CFR 131.180 - Half-and-half.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...). (ii) Natural and artificial food flavoring. (c) Methods of analysis. The milkfat content is determined... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Half-and-half. 131.180 Section 131.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

  17. 21 CFR 131.180 - Half-and-half.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...). (ii) Natural and artificial food flavoring. (c) Methods of analysis. The milkfat content is determined... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Half-and-half. 131.180 Section 131.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

  18. 21 CFR 131.180 - Half-and-half.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...). (ii) Natural and artificial food flavoring. (c) Methods of analysis. The milkfat content is determined... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Half-and-half. 131.180 Section 131.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

  19. 21 CFR 131.180 - Half-and-half.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...). (ii) Natural and artificial food flavoring. (c) Methods of analysis. The milkfat content is determined... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Half-and-half. 131.180 Section 131.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

  20. 21 CFR 131.180 - Half-and-half.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...). (ii) Natural and artificial food flavoring. (c) Methods of analysis. The milkfat content is determined... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Half-and-half. 131.180 Section 131.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

  1. Fused-fiber-based 3-dB mode insensitive power splitters for few-mode optical fiber networks

    NASA Astrophysics Data System (ADS)

    Ren, Fang; Huang, Xiaoshan; Wang, Jianping

    2017-11-01

    We propose a 3-dB mode insensitive power splitter (MIPS) capable of broadcasting and combining optical signals. It is fabricated with two identical few-mode fibers (FMFs) by a heating and pulling technique. The mode-dependent power transfer characteristic as a function of pulling length is investigated. For exploiting its application, we experimentally demonstrate both FMF-based transmissive and reflective star couplers consisting of multiple 3-dB mode insensitive power splitters, which perform broadcasting and routing signals in few-mode optical fiber networks such as mode-division multiplexing (MDM) local area networks using star topology. For experimental demonstration, optical on-off keying signals at 10 Gb/s carried on three spatial modes are successfully processed with open and clear eye diagrams. Measured bit error ratio results show reasonable power penalties. It is found that a reflective star coupler in MDM networks can reduce half of the total amount of required fibers comparing to that of a transmissive star coupler. This MIPS is more efficient, more reliable, more flexible, and more cost-effective for future expansion and application in few-mode optical fiber networks.

  2. Mode of Delivery and Long-Term Health-Related Quality-of-Life Outcomes: A Prospective Population-Based Study.

    PubMed

    Petrou, Stavros; Kim, Sung Wook; McParland, Penny; Boyle, Elaine M

    2017-06-01

    Relatively little is known about the effects of mode of delivery on long-term health-related quality-of-life outcomes. Furthermore, no previous study has expressed these outcomes in preference-based (utility) metrics. The study population comprised 2,161 mothers recruited from a prospective population-based study in the East Midlands of England encompassing live births and stillbirths between 32 +0 and 36 +6 weeks' gestation and a sample of term-born controls. Perinatal data were extracted from the mothers' maternity records. Health-related quality-of-life outcomes were assessed at 12 months postpartum, using the EuroQol Five Dimensions (EQ-5D) measure with responses to the EQ-5D descriptive system converted into health utility scores. Descriptive statistics and multivariable analyses were used to estimate the relationship between the mode of delivery and health-related quality-of-life outcomes. The overall health-related quality-of-life profile of the women in the study cohort mirrored that of the English adult population as revealed by national health surveys. A significantly higher proportion of women delivering by cesarean delivery reported some, moderate, severe, or extreme pain or discomfort at 12 months postpartum than women undergoing spontaneous vaginal delivery. Multivariable analyses, using the Ordinary Least Squares estimator revealed that, after controlling for maternal sociodemographic characteristics, cesarean delivery without maternal or fetal compromise was associated with a significant EQ-5D utility decrement in comparison to spontaneous vaginal delivery among all women (-0.026; p = 0.038) and among mothers of term-born infants (-0.062; p < 0.001). Among mothers of term-born infants, this result was replicated in models that controlled for all maternal and infant characteristics (utility decrement of -0.061; p < 0.001). The results were confirmed by sensitivity analyses that varied the categorization of the main exposure variable (mode of delivery

  3. Calculated half-lives and kinetic energies for spontaneous emission of heavy ions from nuclei

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

    Poenaru, D.N.; Greiner, W.; Depta, K.

    The most probable decays by spontaneous emission of heavy ions are listed for nuclides with Z = 47--106 and total half-lives>1 ..mu..sec. Partial half-lives, branching ratios relative to ..cap alpha.. decay, kinetic energies, and Q values are estimated by using the analytical superasymmetric fission model, a semiempirical formula for those ..cap alpha..-decay lifetimes which have not been measured, and the new Wapstra--Audi mass tables. Numerous ''stable'' nuclides with Z>40 are found to be metastable with respect to the new decay modes. The current experimental status is briefly reviewed.

  4. The Half Empty Question for Socio-Cognitive Interventions

    ERIC Educational Resources Information Center

    Schwartz, Daniel L.; Cheng, Katherine M.; Salehi, Shima; Wieman, Carl

    2016-01-01

    The studies in this special section of the "Journal of Educational Psychology" present a variety of social-psychological interventions across large numbers of classrooms and populations. They show notable benefits for many students at risk for low performance. This is the glass half-full interpretation, and we consider the strengths of…

  5. Detection of Rotational Sequences for Global Oscillation Modes inside the Sun

    NASA Technical Reports Server (NTRS)

    Wolff, Charles L.; Niemann, Hasso B. (Technical Monitor)

    2002-01-01

    A very simple mathematical sequence is detected in a half century of thermal radio flux from the Sun. Since the only known physical cause of the sequence is global oscillations trapped in the nonconvecting solar interior, g-modes and probably r-modes are active. If so, their rotation frequencies are detected and some previously reported difference frequencies are confirmed with high confidence. All angular harmonics for 2 less than or = l less than or = 7 are detected as well as some others up to the limit l less than or = 14 resolvable by the observations (a Fourier spectrum of the 10.7 cm flux time series). The mean sidereal rotation of the nonconvecting interior is 428.2 nHz as averaged by g-modes and 429.8 nHz by the r-modes, indicating that g-mode energy is a bit more centrally concentrated. Helioseismology measures such rotation rates near 0.36R (R = solar radius), so the global modes would have about half their kinetic energy above and below that level. This, and the known log(r) energy dependence of most modes implies that these oscillations are significantly reflected near 0.18R, the same level at which sound speed measurements display a maximum departure from theoretical models.

  6. Dynamics of a feline virus with two transmission modes within exponentially growing host populations.

    PubMed Central

    Berthier, K; Langlais, M; Auger, P; Pontier, D

    2000-01-01

    Feline panleucopenia virus (FPLV) was introduced in 1977 on Marion Island (in the southern Indian Ocean) with the aim of eradicating the cat population and provoked a huge decrease in the host population within six years. The virus can be transmitted either directly through contacts between infected and healthy cats or indirectly between a healthy cat and the contaminated environment: a specific feature of the virus is its high rate of survival outside the host. In this paper, a model was designed in order to take these two modes of transmission into account. The results showed that a mass-action incidence assumption was more appropriate than a proportionate mixing one in describing the dynamics of direct transmission. Under certain conditions the virus was able to control the host population at a low density. The indirect transmission acted as a reservoir supplying the host population with a low but sufficient density of infected individuals which allowed the virus to persist. The dynamics of the infection were more affected by the demographic parameters of the healthy hosts than by the epidemiological ones. Thus, demographic parameters should be precisely measured in field studies in order to obtain accurate predictions. The predicted results of our model were in good agreement with observations. PMID:11416908

  7. The Atacama B-mode Search: Status and Prospect

    NASA Astrophysics Data System (ADS)

    Kusaka, Akito

    2013-04-01

    The Atacama B-mode Search (ABS) experiment is a 145 GHz polarimeter designed to measure the B-mode polarization of the Cosmic Microwave Background (CMB) at degre angular scales. In January 2012, ABS has deployed 240 polarimeters employing transition-edge sensor (TES) bolometers. ABS has unique advantages for the measurement of B modes. This includes a continuously rotating half-wave plate that provides fast and clean modulation, as well as systematically clean optics that consist of a cryogenic side-fed Dragone telescope and feedhorn coupled TES polarimeters. In this talk, we will present the status and prospect of ABS.

  8. A calculation model to half-life estimate of two-proton radioactive decay process

    NASA Astrophysics Data System (ADS)

    Tavares, O. A. P.; Medeiros, E. L.

    2018-04-01

    Partial half-life of the radioactive decay by the two-proton emission mode has been estimated for proton-rich nuclei of mass number 18 < A < 68 by a model based on the quantum mechanical tunneling mechanism through a potential barrier. The Coulomb, centrifugal and overlapping contributions to the barrier have been considered within the spherical nucleus approximation. The present calculation method has been shown to be adequate in reproducing the existing experimental half-life data for 19Mg, 45Fe, 48Ni, and 54Zn 2p-emitter nuclides within a factor six. For 67Kr parent nucleus the calculated partial 2p-decay half-life has been found to be ten times greater than the recent, unique measured value at RIKEN Nishina Center. Prediction for new, yet unmeasured cases of two-proton radioactivity are also reported.

  9. Surface vibrational modes in disk-shaped resonators.

    PubMed

    Dmitriev, A V; Gritsenko, D S; Mitrofanov, V P

    2014-03-01

    The natural frequencies and distributions of displacement components for the surface vibrational modes in thin isotropic elastic disks are calculated. In particular, the research is focused on even solutions for low-lying resonant vibrations with large angular wave numbers. Several families of modes are found which are interpreted as modified surface modes of an infinitely long cylinder and Lamb modes of a plate. The results of calculation are compared with the results of the experimental measurements of vibrational modes generated by means of resonant excitation in duraluminum disk with radius of ≈90 mm and thickness of 16 mm in the frequency range of 130-200 kHz. An excellent agreement between the calculated and measured frequencies is found. Measurements of the structure of the resonant peaks show splitting of some modes. About a half of the measured modes has splitting Δfsplit/fmode at the level of the order of 10(-5). The Q-factors of all modes measured in vacuum lie in the interval (2…3)×10(5). This value is typical for duraluminum mechanical resonators in the ultrasonic frequency range. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Mode of delivery and the probability of subsequent childbearing: a population-based register study.

    PubMed

    Elvander, C; Dahlberg, J; Andersson, G; Cnattingius, S

    2015-11-01

    To investigate the relationship between mode of first delivery and probability of subsequent childbearing. Population-based study. Nationwide study in Sweden. A cohort of 771 690 women who delivered their first singleton infant in Sweden between 1992 and 2010. Using Cox's proportional-hazards regression models, risks of subsequent childbearing were compared across four modes of delivery. Hazard ratios (HRs) were calculated, using 95% confidence intervals (95% CIs). Probability of having a second and third child; interpregnancy interval. Compared with women who had a spontaneous vaginal first delivery, women who delivered by vacuum extraction were less likely to have a second pregnancy (HR 0.96, 95% CI 0.95-0.97), and the probabilities of a second childbirth were substantially lower among women with a previous emergency caesarean section (HR 0.85, 95% CI 0.84-0.86) or an elective caesarean section (HR 0.82, 95% CI 0.80-0.83). There were no clinically important differences in the median time between first and second pregnancy by mode of first delivery. Compared with women younger than 30 years of age, older women were more negatively affected by a vacuum extraction with respect to the probability of having a second child. A primary vacuum extraction decreased the probability of having a third child by 4%, but having two consecutive vacuum extraction deliveries did not further alter the probability. A first delivery by vacuum extraction does not reduce the probability of subsequent childbearing to the same extent as a first delivery by emergency or elective caesarean section. © 2014 Royal College of Obstetricians and Gynaecologists.

  11. Predictive Variables of Half-Marathon Performance for Male Runners

    PubMed Central

    Gómez-Molina, Josué; Ogueta-Alday, Ana; Camara, Jesus; Stickley, Christoper; Rodríguez-Marroyo, José A.; García-López, Juan

    2017-01-01

    The aims of this study were to establish and validate various predictive equations of half-marathon performance. Seventy-eight half-marathon male runners participated in two different phases. Phase 1 (n = 48) was used to establish the equations for estimating half-marathon performance, and Phase 2 (n = 30) to validate these equations. Apart from half-marathon performance, training-related and anthropometric variables were recorded, and an incremental test on a treadmill was performed, in which physiological (VO2max, speed at the anaerobic threshold, peak speed) and biomechanical variables (contact and flight times, step length and step rate) were registered. In Phase 1, half-marathon performance could be predicted to 90.3% by variables related to training and anthropometry (Equation 1), 94.9% by physiological variables (Equation 2), 93.7% by biomechanical parameters (Equation 3) and 96.2% by a general equation (Equation 4). Using these equations, in Phase 2 the predicted time was significantly correlated with performance (r = 0.78, 0.92, 0.90 and 0.95, respectively). The proposed equations and their validation showed a high prediction of half-marathon performance in long distance male runners, considered from different approaches. Furthermore, they improved the prediction performance of previous studies, which makes them a highly practical application in the field of training and performance. Key points The present study obtained four equations involving anthropometric, training, physiological and biomechanical variables to estimate half-marathon performance. These equations were validated in a different population, demonstrating narrows ranges of prediction than previous studies and also their consistency. As a novelty, some biomechanical variables (i.e. step length and step rate at RCT, and maximal step length) have been related to half-marathon performance. PMID:28630571

  12. Transverse single-mode edge-emitting lasers based on coupled waveguides.

    PubMed

    Gordeev, Nikita Yu; Payusov, Alexey S; Shernyakov, Yuri M; Mintairov, Sergey A; Kalyuzhnyy, Nikolay A; Kulagina, Marina M; Maximov, Mikhail V

    2015-05-01

    We report on the transverse single-mode emission from InGaAs/GaAs quantum well edge-emitting lasers with broadened waveguide. The lasers are based on coupled large optical cavity (CLOC) structures where high-order vertical modes of the broad active waveguide are suppressed due to their resonant tunneling into a coupled single-mode passive waveguide. The CLOC lasers have shown stable Gaussian-shaped vertical far-field profiles with a reduced divergence of ∼22° FWHM (full width at half-maximum) in CW (continuous-wave) operation.

  13. Cultural evolution of hinoeuma superstition controlling human mate choice: The role of half-believer.

    PubMed

    Hara, Makoto; Lee, Joung-Hun; Iwasa, Yoh

    2015-11-21

    In this study, we used a cultural dynamic model to explain the persistence of the hinoeuma superstition in traditional Japan. Men with this superstition avoid marrying women born in a hinoeuma year (or hinoeuma-women). Parents avoided childbirth during the last hinoeuma year out of the concern that their daughter would have trouble finding a husband in the future, and this resulted in a large drop in the number of babies born in 1966. A previous theoretical analysis of the hinoeuma superstition considered two alternative cultural factors: believers and nonbelievers. In the present study, we considered a third cultural factor, the half-believer. A man that is a half-believer accepts a hinoeuma-woman as his wife, but parents that are half-believers avoid childbirth during hinoeuma years. With these three cultural factors, there are two possible outcomes for the population. In the first outcome, [1] non-believers become extinct, with the population consisting of believers and half-believers; some men refuse hinoeuma-women as their mate choice, and most parents attempt to avoid childbirth during hinoeuma years. In the second outcome, [2] believers become extinct, and the remaining population consists of non-believers and half-believers; no man refuses hinoeuma-women, and some parents avoid childbirth in hinoeuma years to prevent potential harm to their daughters. If birth control fails at a steady rate, believers will become extinct eventually. The superstition is more likely to be maintained if the mother has a stronger influence on the beliefs of her children than the father. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. [The becoming of public medicine in the second half of XVIII-first half of XIX centuries. Report II. The development of public systems of training of medical manpower and charity provision to socially unprotected groups of population].

    PubMed

    Stochik, A M; Zatravkin, S N; Stochik, A A

    2013-01-01

    The present report considers the history of becoming of concept of medical police in second half of XVIII century. This concept became one of the most important instruments of public management in Austria, France, Prussia and Russia. Two directions of activity of public authorities in the area of implementation of medical police are discussed i.e. control of frauds and development of public systems of training of medical manpower and charity provision to socially unprotected groups of population. The historiographical data is presented concerning the development of public systems of training of medical manpower, reform of university medical education, implementation of hospital reform.

  15. Farm Population of the United States: 1977. Current Population Reports: Farm Population.

    ERIC Educational Resources Information Center

    Banks, Vera J.; DeAre, Diana

    The farm population has declined fairly steadily for more than half a century. By 1970 the proportion of the U.S. population residing on farms had fallen to about 5 per cent, and by 1977 had dropped to 3.6 per cent. About 1.4 per cent of the farm population was of Spanish origin (represented for the first time in this year's report), as compared…

  16. Does interview mode matter for food security measurement? Telephone versus in-person interviews in the Current Population Survey Food Security Supplement.

    PubMed

    Nord, Mark; Hopwood, Heather

    2007-12-01

    To assess whether interview mode (telephone vs. in-person) affects the results of surveys that measure food security. Responses given by households interviewed by telephone and in-person in recent US Current Population Survey Food Security Supplements (CPS-FSS) were compared. Statistical methods based on the Rasch measurement model were used to assess whether response patterns differed between the two interview modes. Multivariate logistic regression analysis was then used to gauge the effect of interview mode on the measured household prevalence rates of food insecurity and very low food security while controlling for income, employment, household structure, and other household characteristics that affect food security. Response patterns to the indicators that comprise the food security scale did not differ substantially between interview modes. Prevalence rates of food insecurity and very low food security estimated from the two interview modes differed by only small proportions after accounting for differences in the socio-economic characteristics of households. Findings suggest that effects of interview mode on food security measurement in the CPS-FSS are small, or at most modest. Prevalence estimates may be biased upwards somewhat for households interviewed in-person compared with those interviewed by telephone. The extent to which these results can be generalised may depend, to some extent, on survey characteristics other than interview mode, such as surveyor name recognition and respondents' trust and confidence in the surveyor.

  17. Lamb Shift in the Near Field of Hyperbolic Metamaterial Half Space

    NASA Astrophysics Data System (ADS)

    Deng, Nai Jing; Yu, Kin Wah

    2013-03-01

    Hyperbolic metamaterials give a large magnification of the density of states in a specific frequency ranges, and has motivated various applications in emission lifetime reduction, strong absorption, and extraordinary black body radiation, etc. The boost of vacuum energy, which is proportional to the density of states, is expected in hyperbolic metamaterial. We have studied the Lamb shift in vacuum-hyperbolic-metamterial half spaces and shown the non-trivial role of vacuum energy. In our calculation, the easy-fabricated multilayer structure is employed to generate a hyperbolic dispersion relation. The spectrum of hydrogen atoms is calculated with a perturbation method after quantizing the half spaces with a complete mode expansion. It appears that the shift of spectrum is mainly contributed by the terahertz response of materials, which has been well described and predicted in both theories and experiments. Work supported by the General Research Fund of the Hong Kong SAR Government

  18. Characterization of the Atacama B-mode Search

    NASA Astrophysics Data System (ADS)

    Simon, S. M.; Raghunathan, S.; Appel, J. W.; Becker, D. T.; Campusano, L. E.; Cho, H. M.; Essinger-Hileman, T.; Ho, S. P.; Irwin, K. D.; Jarosik, N.; Kusaka, A.; Niemack, M. D.; Nixon, G. W.; Nolta, M. R.; Page, L. A.; Palma, G. A.; Parker, L. P.; Sievers, J. L.; Staggs, S. T.; Visnjic, K.

    2014-07-01

    The Atacama B-mode Search (ABS), which began observations in February of 2012, is a crossed-Dragone telescope located at an elevation of 5190 m in the Atacama Desert in Chile. ABS is searching for the B-mode polarization spectrum of the cosmic microwave background (CMB) at large angular scales from multipole moments of ` ~ 50 ~ 500, a range that includes the primor- dial B-mode peak from inflationary gravity waves at ~ 100. The ABS focal plane consists of 240 pixels sensitive to 145 GHz, each containing two transition-edge sensor bolometers coupled to orthogonal polarizations with a planar ortho-mode transducer. An ambient-temperature con- tinuously rotating half-wave plate and 4 K optics make the ABS instrument unique. We discuss the characterization of the detector spectral responses with a Fourier transform spectrometer and demonstrate that the pointing model is adequate. We also present measurements of the beam from point sources and compare them with simulations.

  19. Centromere Locations in Brassica A and C Genomes Revealed Through Half-Tetrad Analysis

    PubMed Central

    Mason, Annaliese S.; Rousseau-Gueutin, Mathieu; Morice, Jérôme; Bayer, Philipp E.; Besharat, Naghmeh; Cousin, Anouska; Pradhan, Aneeta; Parkin, Isobel A. P.; Chèvre, Anne-Marie; Batley, Jacqueline; Nelson, Matthew N.

    2016-01-01

    Locating centromeres on genome sequences can be challenging. The high density of repetitive elements in these regions makes sequence assembly problematic, especially when using short-read sequencing technologies. It can also be difficult to distinguish between active and recently extinct centromeres through sequence analysis. An effective solution is to identify genetically active centromeres (functional in meiosis) by half-tetrad analysis. This genetic approach involves detecting heterozygosity along chromosomes in segregating populations derived from gametes (half-tetrads). Unreduced gametes produced by first division restitution mechanisms comprise complete sets of nonsister chromatids. Along these chromatids, heterozygosity is maximal at the centromeres, and homologous recombination events result in homozygosity toward the telomeres. We genotyped populations of half-tetrad-derived individuals (from Brassica interspecific hybrids) using a high-density array of physically anchored SNP markers (Illumina Brassica 60K Infinium array). Mapping the distribution of heterozygosity in these half-tetrad individuals allowed the genetic mapping of all 19 centromeres of the Brassica A and C genomes to the reference Brassica napus genome. Gene and transposable element density across the B. napus genome were also assessed and corresponded well to previously reported genetic map positions. Known centromere-specific sequences were located in the reference genome, but mostly matched unanchored sequences, suggesting that the core centromeric regions may not yet be assembled into the pseudochromosomes of the reference genome. The increasing availability of genetic markers physically anchored to reference genomes greatly simplifies the genetic and physical mapping of centromeres using half-tetrad analysis. We discuss possible applications of this approach, including in species where half-tetrads are currently difficult to isolate. PMID:26614742

  20. Centromere Locations in Brassica A and C Genomes Revealed Through Half-Tetrad Analysis.

    PubMed

    Mason, Annaliese S; Rousseau-Gueutin, Mathieu; Morice, Jérôme; Bayer, Philipp E; Besharat, Naghmeh; Cousin, Anouska; Pradhan, Aneeta; Parkin, Isobel A P; Chèvre, Anne-Marie; Batley, Jacqueline; Nelson, Matthew N

    2016-02-01

    Locating centromeres on genome sequences can be challenging. The high density of repetitive elements in these regions makes sequence assembly problematic, especially when using short-read sequencing technologies. It can also be difficult to distinguish between active and recently extinct centromeres through sequence analysis. An effective solution is to identify genetically active centromeres (functional in meiosis) by half-tetrad analysis. This genetic approach involves detecting heterozygosity along chromosomes in segregating populations derived from gametes (half-tetrads). Unreduced gametes produced by first division restitution mechanisms comprise complete sets of nonsister chromatids. Along these chromatids, heterozygosity is maximal at the centromeres, and homologous recombination events result in homozygosity toward the telomeres. We genotyped populations of half-tetrad-derived individuals (from Brassica interspecific hybrids) using a high-density array of physically anchored SNP markers (Illumina Brassica 60K Infinium array). Mapping the distribution of heterozygosity in these half-tetrad individuals allowed the genetic mapping of all 19 centromeres of the Brassica A and C genomes to the reference Brassica napus genome. Gene and transposable element density across the B. napus genome were also assessed and corresponded well to previously reported genetic map positions. Known centromere-specific sequences were located in the reference genome, but mostly matched unanchored sequences, suggesting that the core centromeric regions may not yet be assembled into the pseudochromosomes of the reference genome. The increasing availability of genetic markers physically anchored to reference genomes greatly simplifies the genetic and physical mapping of centromeres using half-tetrad analysis. We discuss possible applications of this approach, including in species where half-tetrads are currently difficult to isolate. Copyright © 2016 by the Genetics Society of America.

  1. Maximum likelihood estimation of linkage disequilibrium in half-sib families.

    PubMed

    Gomez-Raya, L

    2012-05-01

    Maximum likelihood methods for the estimation of linkage disequilibrium between biallelic DNA-markers in half-sib families (half-sib method) are developed for single and multifamily situations. Monte Carlo computer simulations were carried out for a variety of scenarios regarding sire genotypes, linkage disequilibrium, recombination fraction, family size, and number of families. A double heterozygote sire was simulated with recombination fraction of 0.00, linkage disequilibrium among dams of δ=0.10, and alleles at both markers segregating at intermediate frequencies for a family size of 500. The average estimates of δ were 0.17, 0.25, and 0.10 for Excoffier and Slatkin (1995), maternal informative haplotypes, and the half-sib method, respectively. A multifamily EM algorithm was tested at intermediate frequencies by computer simulation. The range of the absolute difference between estimated and simulated δ was between 0.000 and 0.008. A cattle half-sib family was genotyped with the Illumina 50K BeadChip. There were 314,730 SNP pairs for which the sire was a homo-heterozygote with average estimates of r2 of 0.115, 0.067, and 0.111 for half-sib, Excoffier and Slatkin (1995), and maternal informative haplotypes methods, respectively. There were 208,872 SNP pairs for which the sire was double heterozygote with average estimates of r2 across the genome of 0.100, 0.267, and 0.925 for half-sib, Excoffier and Slatkin (1995), and maternal informative haplotypes methods, respectively. Genome analyses for all possible sire genotypes with 829,042 tests showed that ignoring half-sib family structure leads to upward biased estimates of linkage disequilibrium. Published inferences on population structure and evolution of cattle should be revisited after accommodating existing half-sib family structure in the estimation of linkage disequilibrium.

  2. Maximum Likelihood Estimation of Linkage Disequilibrium in Half-Sib Families

    PubMed Central

    Gomez-Raya, L.

    2012-01-01

    Maximum likelihood methods for the estimation of linkage disequilibrium between biallelic DNA-markers in half-sib families (half-sib method) are developed for single and multifamily situations. Monte Carlo computer simulations were carried out for a variety of scenarios regarding sire genotypes, linkage disequilibrium, recombination fraction, family size, and number of families. A double heterozygote sire was simulated with recombination fraction of 0.00, linkage disequilibrium among dams of δ = 0.10, and alleles at both markers segregating at intermediate frequencies for a family size of 500. The average estimates of δ were 0.17, 0.25, and 0.10 for Excoffier and Slatkin (1995), maternal informative haplotypes, and the half-sib method, respectively. A multifamily EM algorithm was tested at intermediate frequencies by computer simulation. The range of the absolute difference between estimated and simulated δ was between 0.000 and 0.008. A cattle half-sib family was genotyped with the Illumina 50K BeadChip. There were 314,730 SNP pairs for which the sire was a homo-heterozygote with average estimates of r2 of 0.115, 0.067, and 0.111 for half-sib, Excoffier and Slatkin (1995), and maternal informative haplotypes methods, respectively. There were 208,872 SNP pairs for which the sire was double heterozygote with average estimates of r2 across the genome of 0.100, 0.267, and 0.925 for half-sib, Excoffier and Slatkin (1995), and maternal informative haplotypes methods, respectively. Genome analyses for all possible sire genotypes with 829,042 tests showed that ignoring half-sib family structure leads to upward biased estimates of linkage disequilibrium. Published inferences on population structure and evolution of cattle should be revisited after accommodating existing half-sib family structure in the estimation of linkage disequilibrium. PMID:22377635

  3. Use of the fractional Fourier transform in {pi}/2 converters of laser modes

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

    Malyutin, A A

    2004-02-28

    The possibility of using the fractional Fourier transform (FrFT) in optical schemes for astigmatic {pi}/2 converters of Hermite-Gaussian modes to donut Laguerre-Gaussian modes is considered. Several schemes of converters based on the FrFT of the half-integer and irrational orders are presented. The lowest FrFT order than can be used in astigmatic mode converters is found. The properties of converters based on the fractional and ordinary Fourier transforms are compared. (laser beams)

  4. Modeling of the response of the POLARBEAR bolometers with a continuously rotating half-wave plate

    NASA Astrophysics Data System (ADS)

    Takakura, Satoru; POLARBEAR Collaboration

    2018-01-01

    The curly pattern, the so-called B-mode, in the polarization anisotropy of the cosmic microwave background (CMB) is a powerful probe to measure primordial gravitational waves from the cosmic inflation, as well as the weak lensing due to the large scale structure of the Universe. At present, ground-based CMB experiments with a few arcminutes resolution such as POLARBEAR, SPTpol, and ACTPol have successfully measured the angular power spectrum of the B-mode only in sub-degree scales, though these experiments also have potential to measure the inflationary B-modes in degree scales in absence of the low-frequency noise (1/f noise). Thus, techniques of polarization signal modulation such as a continuously rotating half-wave plate (CRHWP) are widely investigated to suppress the 1/f noise and also to reduce instrumental systematic errors. In this study, we have implemented a CRHWP placed around the prime focus of the POLARBEAR telescope and operated at ambient temperatures. We construct a comprehensive model including half-wave plate synchronous signals, detector non-linearities, beam imperfections, and all noise sources. Using this model, we show that, in practice, the 1/f noise and instrumental systematics could remain even with the CRHWP. However, we also evaluate those effects from test observations using a prototype CRHWP on the POLARBEAR telescope and find that the residual 1/f noise is sufficiently small for POLARBEAR to probe the multipoles about 40. We will also discuss prospects for future CMB experiments with better sensitivities.

  5. Multiple harmonic frequencies resonant cavity design and half-scale prototype measurements for a fast kicker

    DOE PAGES

    Huang, Yulu; Wang, Haipeng; Wang, Shaoheng; ...

    2016-12-09

    Quarter wavelength resonator (QWR) based deflecting cavities with the capability of supporting multiple odd-harmonic modes have been developed for an ultrafast periodic kicker system in the proposed Jefferson Lab Electron Ion Collider (JLEIC, formerly MEIC). Previous work on the kicking pulse synthesis and the transverse beam dynamics tracking simulations show that a flat-top kicking pulse can be generated with minimal emittance growth during injection and circulation of the cooling electron bunches. This flat-top kicking pulse can be obtained when a DC component and 10 harmonic modes with appropriate amplitude and phase are combined together. To support 10 such harmonic modes,more » four QWR cavities are used with 5, 3, 1, and 1 modes, respectively. In the multiple-mode cavities, several slightly tapered segments of the inner conductor are introduced to tune the higher order deflecting modes to be harmonic, and stub tuners are used to fine tune each frequency to compensate for potential errors. In this paper, we summarize the electromagnetic design of the five-mode cavity, including the geometry optimization to get high transverse shunt impedance, the frequency tuning and sensitivity analysis, and the single loop coupler design for coupling to all of the harmonic modes. In particular we report on the design and fabrication of a half-scale copper prototype of this proof-of-principle five-odd-mode cavity, as well as the rf bench measurements. Lastly, we demonstrate mode superposition in this cavity experimentally, which illustrates the kicking pulse generation concept.« less

  6. A transportable 50 kA dual mode lightning simulator

    NASA Technical Reports Server (NTRS)

    Salisbury, K.; Lloyd, S.; Chen, Y. G.

    1991-01-01

    A transportable lightning simulator was designed, built and tested, which is capable of delivering more than 50 kA to an 8 micro-H test object. The simulator was designed to be a versatile device in the lightning laboratory while meeting the requirements of MIL-STD-1757A for component E current waveforms. The system is capable of operating in either a ringing mode with a Q greater than 5 and a nominal frequency of 160 kHz, or a unipolar mode with no hardware configuration changes. The ringing mode is obtained by the LCR series circuit formed by the pulse generator and test object. The unipolar mode is obtained by closing an electrically triggered crowbar switch at peak current. The simulator exceeds the peak current requirement and rate of rise requirements for MIL-STD-1757A in both the ringing and unipolar modes. The pulse half width in the unipolar mode is in excess of 50 microsec and the action is in excess of 10(exp 5) A(exp 2)s. The design, component values, and test results are presented.

  7. Optical preparation of H2 rovibrational levels with almost complete population transfer.

    PubMed

    Dong, Wenrui; Mukherjee, Nandini; Zare, Richard N

    2013-08-21

    Using stimulated Raman adiabatic passage (SARP), it is possible, in principle, to transfer all the population in a rovibrational level of an isolated diatomic molecule to an excited rovibrational level. We use an overlapping sequence of pump (532 nm) and dump (683 nm) single-mode laser pulses of unequal fluence to prepare isolated H2 molecules in a molecular beam. In a first series of experiments we were able to transfer more than half the population to an excited rovibrational level [N. Mukherjee, W. R. Dong, J. A. Harrison, and R. N. Zare, J. Chem. Phys. 138(5), 051101-1-051101-4 (2013)]. Since then, we have achieved almost complete transfer (97% ± 7%) of population from the H2 (v = 0, J = 0) ground rovibrational level to the H2 (v = 1, J = 0) excited rovibrational level. An explanation is presented of the SARP process and how these results are obtained.

  8. Optical preparation of H2 rovibrational levels with almost complete population transfer

    NASA Astrophysics Data System (ADS)

    Dong, Wenrui; Mukherjee, Nandini; Zare, Richard N.

    2013-08-01

    Using stimulated Raman adiabatic passage (SARP), it is possible, in principle, to transfer all the population in a rovibrational level of an isolated diatomic molecule to an excited rovibrational level. We use an overlapping sequence of pump (532 nm) and dump (683 nm) single-mode laser pulses of unequal fluence to prepare isolated H2 molecules in a molecular beam. In a first series of experiments we were able to transfer more than half the population to an excited rovibrational level [N. Mukherjee, W. R. Dong, J. A. Harrison, and R. N. Zare, J. Chem. Phys. 138(5), 051101-1051101-4 (2013)], 10.1063/1.4790402. Since then, we have achieved almost complete transfer (97% ± 7%) of population from the H2 (v = 0, J = 0) ground rovibrational level to the H2 (v = 1, J = 0) excited rovibrational level. An explanation is presented of the SARP process and how these results are obtained.

  9. Mode-based microparticle conveyor belt in air-filled hollow-core photonic crystal fiber.

    PubMed

    Schmidt, Oliver A; Euser, Tijmen G; Russell, Philip St J

    2013-12-02

    We show how microparticles can be moved over long distances and precisely positioned in a low-loss air-filled hollow-core photonic crystal fiber using a coherent superposition of two co-propagating spatial modes, balanced by a backward-propagating fundamental mode. This creates a series of trapping positions spaced by half the beat-length between the forward-propagating modes (typically a fraction of a millimeter). The system allows a trapped microparticle to be moved along the fiber by continuously tuning the relative phase between the two forward-propagating modes. This mode-based optical conveyor belt combines long-range transport of microparticles with a positional accuracy of 1 µm. The technique also has potential uses in waveguide-based optofluidic systems.

  10. [Mode of conception, acompanying medical disorders and complications in the second half of pregnancy in women over the age of 35].

    PubMed

    Dakov, T; Dimitrova, V; Maseva, A; Todorov, T

    2014-01-01

    To assess the impact of maternal age on the mode of conception, the incidence of accompanying medical disorders and past surgical procedures (gynecological and non-gynecological) and the complications in the second half of pregnancy (preeclampsia, placenta praevia, placental abruption, preterm delivery) in women ≥ 35 years, followed prospectively. Between 02/2012 - 02/2014 495 pregnant women of ≥ 12 weeks of gestation were enrolled in the study. The patients were admitted for different indications at the Fetal Medicine Clinic of the State University Hospital "Maichin Dom". They were divided in 3 age groups according to age: ≤ 34, 35-39 and ≥ 40 years. The information about pregnancy course and outcome was retrieved from the hospital records or obtained from the patents themselves by phone interviews. The following complications in the second half of pregnancy were analyzed: preeclampsia, placenta praevia, placental abruption, preterm delivery. The data were processed with SPSS 13.0. statistical package. Descriptive and comparative analysis was performed after grouping according to one or more characteristics; p values < 0.05 were considered as evidence of statistical significance for tested effects. The number of patients ≤ 34 years of age was 131/495 (26.5%), between 35-39 years--54/495 (51,.%) and >≥40 years --10/495 (22,.%). Conception by ART was significantly more frequent in women aged >3 5. Pregnancy occurred afterA RTi n 1,.% (2/131) of the women <3 4, in 8,.% (22/254) of those between 35-39 and in 10,.% (12/110) of those >≥ 0 years of age (p= O 0.08). The incidence of accompanying medical disorders (intemrnl, tumors, of the female genital system) was significantly higher in women of more advanced age (p< O 0.01). It was 36,.% (48/131) in those <3 4, 53,1% (135/254) --n the ones between 35-39 and 68,.% (75/110) --mong those >≥ 0 years of age. The increased incidence was mainly due to more frequent intemrnl (p= 0 ,.218) and female reproductive

  11. Predictions on the modes of decay of even Z superheavy isotopes within the range 104 ≤ Z ≤ 136

    NASA Astrophysics Data System (ADS)

    Santhosh, K. P.; Nithya, C.

    2018-01-01

    The decay modes and half lives of all the even Z isotopes of superheavy elements within the range 104 ≤ Z ≤ 136 have been predicted by comparing the alpha decay half-lives with the spontaneous fission half-lives. The Coulomb and proximity potential model for deformed nuclei (CPPMDN) and the shell-effect-dependent formula of Santhosh et al. are used to calculate the alpha half-lives and spontaneous fission half-lives respectively. For theoretical comparison the alpha decay half-lives are also calculated using Coulomb and proximity potential model (CPPM), the Viola-Seaborg-Sobiczewski semi-empirical (VSS) relation, the universal (UNIV) curve of Poenaru et al., the analytical formula of Royer and the universal decay law (UDL) of Qi et al. Another tool used for the evaluation of spontaneous fission half-lives is the semi-empirical formula of Xu et al. The nuclei with alpha decay half-lives less than spontaneous fission half-lives will survive fission and hence decay through alpha emission. The predicted half lives and decay modes are compared with the available experimental results. The one-proton and two-proton separation energies of all the isotopes are calculated to find nuclei which lie beyond the proton drip line. Among 1119 even Z nuclei within the range 104 ≤ Z ≤ 136, 164 nuclei show sequential alpha emission followed by subsequent spontaneous fission. Since the isotopes decay through alpha decay chain and the half-lives are in measurable range, these isotopes are predicted to be synthesized and detected in laboratory via alpha decay. 2 nuclei will decay by alpha decay followed by proton emission, 54 nuclei show full alpha chains, 642 nuclei will decay through spontaneous fission, 166 nuclei exhibit proton decay and 91 isotopes are found to be stable against alpha decay. All the isotopes are tabulated according to their decay modes. The study is intended to enhance further experimental investigations in superheavy region.

  12. Approximation to cutoffs of higher modes of Rayleigh waves for a layered earth model

    USGS Publications Warehouse

    Xu, Y.; Xia, J.; Miller, R.D.

    2009-01-01

    A cutoff defines the long-period termination of a Rayleigh-wave higher mode and, therefore is a key characteristic of higher mode energy relationship to several material properties of the subsurface. Cutoffs have been used to estimate the shear-wave velocity of an underlying half space of a layered earth model. In this study, we describe a method that replaces the multilayer earth model with a single surface layer overlying the half-space model, accomplished by harmonic averaging of velocities and arithmetic averaging of densities. Using numerical comparisons with theoretical models validates the single-layer approximation. Accuracy of this single-layer approximation is best defined by values of the calculated error in the frequency and phase velocity estimate at a cutoff. Our proposed method is intuitively explained using ray theory. Numerical results indicate that a cutoffs frequency is controlled by the averaged elastic properties within the passing depth of Rayleigh waves and the shear-wave velocity of the underlying half space. ?? Birkh??user Verlag, Basel 2009.

  13. Looking East at BottomHalf of Reactor Number One and TopHalf ...

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

    Looking East at Bottom-Half of Reactor Number One and Top-Half of Reactor Number 2 Including Weigh Hopper on Third Floor of Oxide Building - Hematite Fuel Fabrication Facility, Oxide Building & Oxide Loading Dock, 3300 State Road P, Festus, Jefferson County, MO

  14. Instantaneous normal mode analysis of the vibrational relaxation of the amide I mode of alanine dipeptide in water.

    PubMed

    Farag, Marwa H; Zúñiga, José; Requena, Alberto; Bastida, Adolfo

    2013-05-28

    Nonequilibrium Molecular Dynamics (MD) simulations coupled to instantaneous normal modes (INMs) analysis are used to study the vibrational relaxation of the acetyl and amino-end amide I modes of the alanine dipeptide (AlaD) molecule dissolved in water (D2O). The INMs are assigned in terms of the equilibrium normal modes using the Effective Atomic Min-Cost algorithm as adapted to make use of the outputs of standard MD packages, a method which is well suited for the description of flexible molecules. The relaxation energy curves of both amide I modes show multiexponential decays, in good agreement with the experimental findings. It is found that ~85%-90% of the energy relaxes through intramolecular vibrational redistribution. The main relaxation pathways are also identified. The rate at which energy is transferred into the solvent is similar for the acetyl-end and amino-end amide I modes. The conformational changes occurring during relaxation are investigated, showing that the populations of the alpha and beta region conformers are altered by energy transfer in such a way that it takes 15 ps for the equilibrium conformational populations to be recovered after the initial excitation of the AlaD molecule.

  15. Half-life measurements of isomeric states populated in projectile fragmentation

    NASA Astrophysics Data System (ADS)

    Bowry, M.; Podolyák, Zs.; Kurcewicz, J.; Pietri, S.; Bunce, M.; Regan, P. H.; Farinon, F.; Geissel, H.; Nociforo, C.; Prochazka, A.; Weick, H.; Allegro, P.; Benlliure, J.; Benzoni, G.; Boutachkov, P.; Gerl, J.; Gorska, M.; Gottardo, A.; Gregor, N.; Janik, R.; Knöbel, R.; Kojouharov, I.; Kubo, T.; Litvinov, Y. A.; Merchan, E.; Mukha, I.; Naqvi, F.; Pfeiffer, B.; Pfützner, M.; Plaß, W.; Pomorski, M.; Riese, B.; Ricciardi, M. V.; Schmidt, K.-H.; Schaffner, H.; Kurz, N.; Denis Bacelar, A. M.; Bruce, A. M.; Farrelly, G. F.; Alkhomashi, N.; Al-Dahan, N.; Scheidenberger, C.; Sitar, B.; Spiller, P.; Stadlmann, J.; Strmen, P.; Sun, B.; Takeda, H.; Tanihata, I.; Terashima, S.; Valiente Dobon, J. J.; Winfield, J. S.; Wollersheim, H.-J.; Woods, P. J.

    2012-10-01

    The half-lives of excited isomeric states observed in 195Au, 201Tl and 215Rn are reported for the first time. Delayed γ-rays were correlated with nuclei produced in the projectile fragmentation of relativistic 238U ions, unambiguously identified in terms of their atomic number (Z) and mass-to-charge ratio (A/Q) after traversing an in-flight separator. The observation of a long-lived isomeric state in 195Au with t1/2 = 16-4+8 μs is presented. Two shorter-lived isomeric states were detected in 201Tl and 215Rn with t1/2 = 95-21+39 and 57-12+21 ns respectively. In total 24 isomeric states were identified in different nuclei from Pt to Rn (A ˜ 200) during the current study, the majority of which were previously reported. The wealth of spectroscopic data provides the opportunity to determine the isomeric ratios over a wide range of Z, A and angular momentum (I ħ) of the reaction products. In particular, high-spin states with I ≳ 18 ħ provide a robust test of theoretical models of fragmentation.

  16. The distribution of new HIV infections by mode of exposure in Morocco

    PubMed Central

    Mumtaz, Ghina R; Kouyoumjian, Silva P; Hilmi, Nahla; Zidouh, Ahmed; Rhilani, Houssine El; Alami, Kamal; Bennani, Aziza; Gouws, Eleanor; Ghys, Peter Denis; Abu-Raddad, Laith J

    2013-01-01

    Objectives Building on a wealth of new empirical data, the objective of this study was to estimate the distribution of new HIV infections in Morocco by mode of exposure using the modes of transmission (MoT) mathematical model. Methods The MoT model was implemented within a collaboration with the Morocco Ministry of Health and the Joint United Nations Programme on HIV/AIDS. The model was parameterised through a comprehensive review and synthesis of HIV and risk behaviour data in Morocco, mainly through the Middle East and North Africa HIV/AIDS Synthesis Project. Uncertainty analyses were used to assess the reliability of and uncertainty around our calculated estimates. Results Female sex workers (FSWs), clients of FSWs, men who have sex with men (MSM) and injecting drug users (IDUs) contributed 14%, 24%, 14% and 7% of new HIV infections, respectively. Two-thirds (67%) of new HIV infections occurred among FSWs, clients of FSWs, MSM and IDUs, or among the stable sexual partners of these populations. Casual heterosexual sex contributed 7% of HIV infections. More than half (52%) of HIV incidence is among females, but 71% of these infections are due to an infected spouse. The vast majority of HIV infections among men (89%) are due to high-risk behaviour. A very small HIV incidence is predicted to arise from medical injections or blood transfusions (0.1%). Conclusions The HIV epidemic in Morocco is driven by HIV incidence in high-risk population groups, with commercial heterosexual sex being the largest contributor to incidence. There is a need to focus HIV response more on these populations, mainly through proactive and sustainable HIV surveillance, and the expansion and increased geographical coverage of services such as condom promotion among FSWs, voluntary counselling and testing, harm reduction and treatment. PMID:23413401

  17. Geo-Demography of HIV/AIDS in Japan from 1985 to 2011: Incidence and Transmission Mode under Influence of Population Size/Density.

    PubMed

    Yoshikura, Hiroshi

    2016-01-01

    A stable relation was found between number of HIV/AIDS patients (P) and population size (N) and between HIV/AIDS incidence (I) and population density (D). The relation could be expressed as P = kN(m) or I = hD(n), where k, h, m, and n are constants. For "AIDS"/"AIDS diagnosis", the constant m was 1.5 for Japan and 1.3 for the United States of America (USA); n was 0.38 for both Japan and the USA. These observations indicated that larger population sizes related to disproportionately larger numbers of HIV/AIDS patients, and denser populations had disproportionately higher incidences of HIV/AIDS. Considering the wide geo-demographic difference between the two countries, it was striking that the same equations with constants within a narrow range were applicable to both Japan and the USA. Modes of HIV transmission appeared to be variable among prefectures in Japan. Homosexual transmission was suggested as being more predominant in more populated prefectures.

  18. A population based evaluation of the mode of delivery in association with infertility treatment from 1990-2012.

    PubMed

    Reichelt, J; Kyvernitakis, I; Misselwitz, B; Hadji, P; Schmidt, S; Kalder, M

    2015-02-01

    This study refers to population based data and investigates the development of the mode of delivery associated with infertility treatment over the last 23 years. All 1 202,557 deliveries in Hesse, Germany, between 1990 and 2012 were assessed. 2.2% of the study population, 26,761, had a delivery subsequent to infertility treatment based on the Hessian Perinatal Registry (HEPE). An evaluation in this subgroup was performed investigating the associations between the mode of delivery and the gestational week and the mother's age. A continuous and significant (p<0.01) increase of cesarean section (CS) rates subsequent to infertility treatment (1990: 41,3%; 2012: 55,9%) as well as a conversely also significant (p<0.01) reduction of vaginal operative and spontaneous deliveries associated with infertility treatment between 1990 and 2012 was found. Furthermore, the preterm delivery rate and the proportion of deliveries of parturients older than 35 years of age in association with infertility treatment raised over the last years. Rates of full-term deliveries and deliveries of women younger than 35 years remained stable during the observation period. The rate of cesarean section is continuously rising over the last 23 years with regard to parturients subsequent to infertility treatment. The CS rate is significantly higher compared to women with a spontaneous pregnancy and in comparison to the data from 20 years ago. Most recently, the number of CS (51,2%) exceeded the number of vaginal deliveries (48,8%) in Hesse subsequent to infertility treatment for the first time. © Georg Thieme Verlag KG Stuttgart · New York.

  19. 2-D modeling of dual-mode acoustic phonon excitation of a triangular nanoplate

    NASA Astrophysics Data System (ADS)

    Tai, Po-Tse; Yu, Pyng; Tang, Jau

    2010-08-01

    In this theoretical work, we investigated coherent phonon excitation of a triangular nanoplate based on 2-D Fermi-Pasta-Ulam lattice model. Based on the two-temperature model commonly used in description of laser heating of metals, we considered two kinds of forces related to electronic and lattice stresses. Based on extensive simulation and analysis, we identified two major planar phonon modes, namely, a standing wave mode related to the triangle bisector and another mode corresponding to half of the side length. This work elucidates the roles of laser-induced electronic stress and lattice stress in controlling the initial phase and the amplitude ratio between these two phonon modes.

  20. Transverse Mode Dynamics of VCSELs Undergoing Current Modulation

    NASA Technical Reports Server (NTRS)

    Goorjian, Peter M.; Ning, C. Z.; Agrawal, Govind

    2000-01-01

    Transverse mode dynamics of a 20-micron-diameter vertical-cavity surface-emitting laser (VCSEL) undergoing gain switching by deep current modulation is studied numerically. The direct current (dc) level is set slightly below threshold and is modulated by a large alternating current (ac). The resulting optical pulse train and transverse-mode patterns are obtained numerically. The ac frequency is varied from 2.5 GHz to 10 GHz, and the ac amplitude is varied from one-half to four times that of the dc level. At high modulation frequencies, a regular pulse train is not generated unless the ac amplitude is large enough. At all modulation frequencies, the transverse spatial profile switches from single-mode to multiple-mode pattern as the ac pumping level is increased. Optical pulse widths vary in the range 5-30 ps. with the pulse width decreasing when either the frequency is increased or the ac amplitude is decreased. The numerical modeling uses an approximation form of the semiconductor Maxwell-Bloch equations. Temporal evolution of the spatial profiles of the laser (and of carrier density) is determined without any assumptions about the type or number of modes. Keywords: VCSELs, current modulation, gain switching, transverse mode dynamics, computational modeling

  1. Numerical Simulation of Dual-Mode Scramjet Combustors

    NASA Technical Reports Server (NTRS)

    Rodriguez, C. G.; Riggins, D. W.; Bittner, R. D.

    2000-01-01

    Results of a numerical investigation of a three-dimensional dual-mode scramjet isolator-combustor flow-field are presented. Specifically, the effect of wall cooling on upstream interaction and flow-structure is examined for a case assuming jet-to-jet symmetry within the combustor. Comparisons are made with available experimental wall pressures. The full half-duct for the isolator-combustor is then modeled in order to study the influence of side-walls. Large scale three-dimensionality is observed in the flow with massive separation forward on the side-walls of the duct. A brief review of convergence-acceleration techniques useful in dual-mode simulations is presented, followed by recommendations regarding the development of a reliable and unambiguous experimental data base for guiding CFD code assessments in this area.

  2. Exciting Reflectionless, Unidirectional Edge Mode in Bianisotropic Meta-waveguide Using Rotating Dipole Antenna

    NASA Astrophysics Data System (ADS)

    Xiao, Bo; Antonsen, Thomas; Ott, Edward; Anlage, Steven; Ma, Tzuhsuan; Shvets, Gennady

    Electronic chiral edge states in Quantum Hall Effect systems has attracted a lot of attention in recent years because of its unique directionality and robustness against scattering from disorder. Its electromagnetic counterpart can be found in photonic crystals, which is a material with periodic dielectric constant. Here we present the experimental results demonstrating the unidirectional edge mode inside a bi-anisotropic meta-waveguide (BMW) structure. It is a parallel plate waveguide with metal rods placed in a hexagonal lattice. Half of the rods are attached to the top plate while the other half are attached to the bottom plate creating a domain wall. The edge mode is excited by two loop antennas placed perpendicular to each other within one wavelength, generating a rotating magnetic dipole that couples to the left or right-going mode. The transmission measurement are taken along the BMW boundary and shows high transmission only around the edge, thus confirming the presence of an edge mode. We also demonstrated that very high directivity can be achieved when the input amplitude and phase of the two loop antennas are tuned properly This work is funded by the ONR under Grants No. N00014130474 and N000141512134, and the Center for Nanophysics and Advanced Materials (CNAM).

  3. Changes over time in population level transport satisfaction and mode of travel: A 13 year repeat cross-sectional study, UK.

    PubMed

    Olsen, Jonathan R; Macdonald, Laura; Ellaway, Anne

    2017-09-01

    The aim of the study was to examine changes over time in satisfaction with usual transport mode, explore individual and area level characteristics as mediators in the likelihood of transport satisfaction, and whether any changes in transport satisfaction varied by these factors over time. Adults from West Central Scotland, United Kingdom, who participated at both waves of the repeat cross-sectional 'Transport, Health and Well-being Study' conducted in 1997 (n=2735) and 2010 (n=2024) were assessed. Individuals completed a detailed postal questionnaire at both time points including self-rated satisfaction with usual transport mode (using a seven point scale subsequently dichotomised to a binary outcome of satisfied (1-2) and other (3-7)). Participants reported usual transport mode for travel to various destinations. A multilevel logistic regression model was used and individuals were nested within areas (c. 4000 population). At the 2010 sweep, two thirds (n=1345) of individuals were satisfied with their transport choice. Those with fair/poor health were less satisfied with their usual transport compared to those in better health (Odds Ratio (OR) 0.49, p<0.001). Access to a car was associated with overall transport satisfaction (OR 2.63, p<0.001) and the effect of deprivation on transport satisfaction was mitigated when adjusted by household car access. Transport satisfaction increased more from 1997 to 2010 for retired individuals compared to those in employment (OR 1.40, p=0.032), and for those who travelled by public transport (OR 2.39, p=0.005) and using multiple modes (OR 2.19, p<0.001) compared to those who travelled by car. The proportion of those who travelled using public transport, active modes or by multiple mode increased journey satisfaction over time at a greater rate than those who travelled by car, highlighting that continued efforts should be made to promote these more active transport modes which have potential to impact on health.

  4. 7 CFR 51.2295 - Half kernel.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Half kernel. 51.2295 Section 51.2295 Agriculture... Standards for Shelled English Walnuts (Juglans Regia) Definitions § 51.2295 Half kernel. Half kernel means the separated half of a kernel with not more than one-eighth broken off. ...

  5. Capillary reference half-cell

    DOEpatents

    Hall, Stephen H.

    1996-01-01

    The present invention is a reference half-cell electrode wherein intermingling of test fluid with reference fluid does not affect the performance of the reference half-cell over a long time. This intermingling reference half-cell may be used as a single or double junction submersible or surface reference electrode. The intermingling reference half-cell relies on a capillary tube having a first end open to reference fluid and a second end open to test fluid wherein the small diameter of the capillary tube limits free motion of fluid within the capillary to diffusion. The electrode is placed near the first end of the capillary in contact with the reference fluid. The method of operation of the present invention begins with filling the capillary tube with a reference solution. After closing the first end of the capillary, the capillary tube may be fully submerged or partially submerged with the second open end inserted into test fluid. Since the electrode is placed near the first end of the capillary, and since the test fluid may intermingle with the reference fluid through the second open end only by diffusion, this intermingling capillary reference half-cell provides a stable voltage potential for long time periods.

  6. Capillary reference half-cell

    DOEpatents

    Hall, S.H.

    1996-02-13

    The present invention is a reference half-cell electrode wherein intermingling of test fluid with reference fluid does not affect the performance of the reference half-cell over a long time. This intermingling reference half-cell may be used as a single or double junction submersible or surface reference electrode. The intermingling reference half-cell relies on a capillary tube having a first end open to reference fluid and a second end open to test fluid wherein the small diameter of the capillary tube limits free motion of fluid within the capillary to diffusion. The electrode is placed near the first end of the capillary in contact with the reference fluid. The method of operation of the present invention begins with filling the capillary tube with a reference solution. After closing the first end of the capillary, the capillary tube may be fully submerged or partially submerged with the second open end inserted into test fluid. Since the electrode is placed near the first end of the capillary, and since the test fluid may intermingle with the reference fluid through the second open end only by diffusion, this intermingling capillary reference half-cell provides a stable voltage potential for long time periods. 11 figs.

  7. Split-mode ultrasonic transducer.

    PubMed

    Ostrovskii, Igor; Cremaldi, Lucien

    2013-08-01

    A split-mode ultrasonic transducer is investigated in both theory and experiment. This transducer is a two-dimensional structure of periodically poled domains in a ferroelectric wafer with free surfaces. The acoustic vibrations are excited by a radio frequency electric current applied along the length of the wafer, which allows the basal-plane surfaces to be free of metal coatings and thus ready for further biomedical applications. A specific physical property of this transducer consists of the multiple acousto-electric resonances, which occur due to an acoustic mode split when the acoustic half-wavelength is equal to the domain length. Possible applications include ultrasonic generation and detection at the micro-scale, intravascular sonification and visualization, ultrasound therapy of localized small areas such as the eye, biomedical applications for cell cultures, and traditional nondestructive testing including bones and tissues. A potential use of a non-metallized wafer is a therapeutic application with double action that is both ultrasound itself and an electric field over the wafer. The experimental measurements and theoretical calculations are in good agreement.

  8. Damping system for torsion modes of mirror isolation filters in TAMA300

    NASA Astrophysics Data System (ADS)

    Arase, Y.; Takahashi, R.; Arai, K.; Tatsumi, D.; Fukushima, M.; Yamazaki, T.; Fujimoto, Masa-Katsu; Agatsuma, K.; Nakagawa, N.

    2008-07-01

    The seismic attenuation system (SAS) in TAMA300 consists of a three-legged inverted pendulum and mirror isolation filters in order to provide a high level of seismic isolation. However, the mirror isolation filters have torsion modes with long decay time which disturb the interferometer operation for about half an hour if they get excited. In order to damp the torsion modes of the filters, we constructed a digital damping system using reflective photosensors with a large linear range. This system was installed to all of four SASs. By damping of the target torsion modes, the effective quality factors of the torsion modes are reduced to less than 10 or to unmeasurable level. This system is expected to reduce the inoperative period by the torsion mode excitation, and thus will contribute to improve the duty time of the gravitational wave detector.

  9. The Disease that Infected Half the World: Mathematics, Biology, and History

    ERIC Educational Resources Information Center

    Miller, Sheila; Helms, Josh

    2010-01-01

    We detail a student project that incorporates the story of the 1918 Influenza Pandemic, which, between the summer of 1918 and the spring of 1919, infected one-fifth to one-half of the world's population and killed more U.S. soldiers fighting in World War I than the war itself. The project uses Susceptible, Infected, Recovered, and Dead (SIRD)…

  10. Campground marketing: the heavy-half strategy

    Treesearch

    Wilbur F. LaPage

    1969-01-01

    When we arrayed camping frequencies in order from the lowest to the highest number of days spent camping per year we found that half of the campers do much more than half of the camping. Campers in this heavy half consistently camp more, year after year, and are increasing their annual participation as well. Heavy-half campers have larger investments in camping...

  11. All-fiber bandpass filter based on asymmetrical modes exciting and coupling

    NASA Astrophysics Data System (ADS)

    Zhang, Qiang; Zhu, Tao; Shi, Leilei; Liu, Min

    2013-01-01

    A low cost all-fiber bandpass filter is demonstrated by fabricating an asymmetric long-period fiber grating (LPFG) in an off-set splicing fiber structure of two single mode fibers in this paper. The main principle of the filter is that the asymmetric LPFG written by single-side CO2 laser irradiation is used to couple the asymmetric cladding modes excited by the offset-coupling of the splicing point between the single mode fiber and the grating, and the left core mode of the splicing point cannot be coupled to the right fiber core, hence the interference effect is avoided. So the bandpass characteristics in the transmission spectrum are achieved. The designed filter exhibits a pass band at a central wavelength of 1565.0 nm with a full-width at half-maximum bandwidth of 12.3 nm.

  12. Kink modes and surface currents associated with vertical displacement events

    NASA Astrophysics Data System (ADS)

    Manickam, Janardhan; Boozer, Allen; Gerhardt, Stefan

    2012-08-01

    The fast termination phase of a vertical displacement event (VDE) in a tokamak is modeled as a sequence of shrinking equilibria, where the core current profile remains constant so that the safety-factor at the axis, qaxis, remains fixed and the qedge systematically decreases. At some point, the n = 1 kink mode is destabilized. Kink modes distort the magnetic field lines outside the plasma, and surface currents are required to nullify the normal component of the B-field at the plasma boundary and maintain equilibrium at finite pressure. If the plasma touches a conductor, the current can be transferred to the conductor, and may be measurable by the halo current monitors. This report describes a practical method to model the plasma as it evolves during a VDE, and determine the surface currents, needed to maintain equilibrium. The main results are that the onset conditions for the disruption are that the growth-rate of the n = 1 kink exceeds half the Alfven time and the associated surface current needed to maintain equilibrium exceeds one half of the core plasma current. This occurs when qedge drops below a low integer, usually 2. Application to NSTX provides favorable comparison with non-axisymmetric halo-current measurements. The model is also applied to ITER and shows that the 2/1 mode is projected to be the most likely cause of the final disruption.

  13. Influencing the Forgotten Half of the Population in Counterinsurgency Operations

    DTIC Science & Technology

    2008-03-01

    and the constant threat of violence , it is often left to women to gather any remaining family and seek safety, sustenance, and shelter. When the family...Counterinsurgency Operations FORMAT: Strategy Research Project DATE: 20 March 2008 WORD COUNT: 6,392 PAGES: 30 KEY TERMS: Women , Gender Concerns...contact with indigenous populations, it is critical for the Army to understand and appreciate the capabilities and potential of indigenous women as

  14. Multi-Generational Kinship, Multiple Mating, and Flexible Modes of Parental Care in a Breeding Population of the Veery (Catharus fuscescens), a Trans-Hemispheric Migratory Songbird

    PubMed Central

    Kalavacharla, Venugopal

    2016-01-01

    We discovered variable modes of parental care in a breeding population of color-banded Veeries (Catharus fuscescens), a Nearctic-Neotropical migratory songbird, long thought to be socially monogamous, and performed a multi-locus DNA microsatellite analysis to estimate parentage and kinship in a sample of 37 adults and 21 offspring. We detected multiple mating in both sexes, and four modes of parental care that varied in frequency within and between years including multiple male feeders at some nests, and males attending multiple nests in the same season, each with a different female. Unlike other polygynandrous systems, genetic evidence indicates that multi-generational patterns of kinship occur among adult Veeries at our study site, and this was corroborated by the capture of an adult male in 2013 that had been banded as a nestling in 2011 at a nest attended by multiple male feeders. All genotyped adults (n = 37) were related to at least one other bird in the sample at the cousin level or greater (r ≥ 0.125), and 81% were related to at least one other bird at the half-sibling level or greater (r ≥ 0.25, range 0.25–0.60). Although our sample size is small, it appears that the kin structure is maintained by natal philopatry in both sexes, and that Veeries avoid mating with close genetic kin. At nests where all adult feeders were genotyped (n = 9), the male(s) were unrelated to the female (mean r = -0.11 ± 0.15), whereas genetic data suggest close kinship (r = 0.254) between two male co-feeders at the nests of two females in 2011, and among three of four females that were mated to the same polygynous male in 2012. To our knowledge, this is the first evidence of polygynandry occurring among multiple generations of close genetic kin on the breeding ground of a Nearctic-Neotropical migratory songbird. PMID:27331399

  15. Exponential protection of zero modes in Majorana islands.

    PubMed

    Albrecht, S M; Higginbotham, A P; Madsen, M; Kuemmeth, F; Jespersen, T S; Nygård, J; Krogstrup, P; Marcus, C M

    2016-03-10

    Majorana zero modes are quasiparticle excitations in condensed matter systems that have been proposed as building blocks of fault-tolerant quantum computers. They are expected to exhibit non-Abelian particle statistics, in contrast to the usual statistics of fermions and bosons, enabling quantum operations to be performed by braiding isolated modes around one another. Quantum braiding operations are topologically protected insofar as these modes are pinned near zero energy, with the departure from zero expected to be exponentially small as the modes become spatially separated. Following theoretical proposals, several experiments have identified signatures of Majorana modes in nanowires with proximity-induced superconductivity and atomic chains, with small amounts of mode splitting potentially explained by hybridization of Majorana modes. Here, we use Coulomb-blockade spectroscopy in an InAs nanowire segment with epitaxial aluminium, which forms a proximity-induced superconducting Coulomb island (a 'Majorana island') that is isolated from normal-metal leads by tunnel barriers, to measure the splitting of near-zero-energy Majorana modes. We observe exponential suppression of energy splitting with increasing wire length. For short devices of a few hundred nanometres, sub-gap state energies oscillate as the magnetic field is varied, as is expected for hybridized Majorana modes. Splitting decreases by a factor of about ten for each half a micrometre of increased wire length. For devices longer than about one micrometre, transport in strong magnetic fields occurs through a zero-energy state that is energetically isolated from a continuum, yielding uniformly spaced Coulomb-blockade conductance peaks, consistent with teleportation via Majorana modes. Our results help to explain the trivial-to-topological transition in finite systems and to quantify the scaling of topological protection with end-mode separation.

  16. The Effects of Mode and Task Complexity on Second Language Production

    ERIC Educational Resources Information Center

    Vasylets, Olena; Gilabert, Roger; Manchón, Rosa M.

    2017-01-01

    Taking a psycholinguistic orientation within task-based language teaching scholarship, this study investigated the effects of mode (oral vs. written) and task complexity on second language (L2) performance. The participants were 78 Catalan/Spanish learners of English as a foreign language. Half of the participants performed the simple and complex…

  17. Phase control of entanglement and quantum steering in a three-mode optomechanical system

    NASA Astrophysics Data System (ADS)

    Sun, F. X.; Mao, D.; Dai, Y. T.; Ficek, Z.; He, Q. Y.; Gong, Q. H.

    2017-12-01

    The theory of phase control of coherence, entanglement and quantum steering is developed for an optomechanical system composed of a single mode cavity containing a partially transmitting dielectric membrane and driven by short laser pulses. The membrane divides the cavity into two mutually coupled optomechanical cavities resulting in an effective three-mode closed loop system, two field modes of the two cavities and a mechanical mode representing the oscillating membrane. The closed loop in the coupling creates interfering channels which depend on the relative phase of the coupling strengths of the field modes to the mechanical mode. Populations and correlations of the output modes are calculated analytically and show several interesting phase dependent effects such as reversible population transfer from one field mode to the other, creation of collective modes, and induced coherence without induced emission. We find that these effects result from perfect mutual coherence between the field modes which is preserved even if one of the modes is not populated. The inseparability criterion for the output modes is also investigated and we find that entanglement may occur only between the field modes and the mechanical mode. We show that depending on the phase, the field modes can act on the mechanical mode collectively or individually resulting, respectively, in tripartite or bipartite entanglement. In addition, we examine the phase sensitivity of quantum steering of the mechanical mode by the field modes. Deterministic phase transfer of the steering from bipartite to collective is predicted and optimum steering corresponding to perfect EPR state can be achieved. These different types of quantum steering can be distinguished experimentally by measuring the coincidence rate between two detectors adjusted to collect photons of the output cavity modes. In particular, we find that the minima of the interference pattern of the coincidence rate signal the bipartite steering

  18. A clinical comparison between a new dual-chamber pacing mode-AAIsafeR and DDD mode.

    PubMed

    Xue-Jun, Ren; Zhihong, Han; Ye, Wang; Huifeng, Du; Jinrong, Zhang; Fang, Chen; Jihong, Guo

    2010-02-01

    The aim of this study was to compare the cross-follow-up results in DDD or AAISafeR mode and to describe the safety and effectiveness of this pacing mode. The Symphony 2450/2550 cardiac pacemakers were implanted in 30 patients with sick sinus syndrome between February 2006 and September 2006. They were randomized to the DDD mode or AAISafeR mode for 3 months and then crossed over to the alternate pacing modality for an additional 3 months. No AAISafeR-related adverse event was observed. All documented episodes of paroxysmal atrial ventricular block caused the immediate switch of the pacing mode from AAI to DDD. The cumulative percent ventricular pacing was significantly reduced in the AAISafeR mode compared with the DDD mode (0.9% [0%-3%] versus 51.3% [2%-91%] P = 0.001; 2.94% [0%-18%] versus 41.18% [0%-65%] P = 0.0001). After 3 months in DDD mode, left atrial diameter, left ventricular enddiastolic diameter, and left ventricular end-systolic diameter increased significantly and left ventricular ejection fraction decreased. However, no obvious changes appeared in 3 months of AAISafeR mode. Switches to DDD occurred during follow-up in 21 patients due to different-degree atrial ventricular block. The AAISafeR mode substantially reduces the amount of unnecessary right ventricular pacing in the bradycardia population and effectively prevents the deleterious effects on cardiac performance. An international randomized study will further ascertain the efficacy of this new pacing mode specifically in the prevention of heart failure hospitalization and atrial fibrillation.

  19. Fragmentation modes and the evolution of life cycles.

    PubMed

    Pichugin, Yuriy; Peña, Jorge; Rainey, Paul B; Traulsen, Arne

    2017-11-01

    Reproduction is a defining feature of living systems. To reproduce, aggregates of biological units (e.g., multicellular organisms or colonial bacteria) must fragment into smaller parts. Fragmentation modes in nature range from binary fission in bacteria to collective-level fragmentation and the production of unicellular propagules in multicellular organisms. Despite this apparent ubiquity, the adaptive significance of fragmentation modes has received little attention. Here, we develop a model in which groups arise from the division of single cells that do not separate but stay together until the moment of group fragmentation. We allow for all possible fragmentation patterns and calculate the population growth rate of each associated life cycle. Fragmentation modes that maximise growth rate comprise a restrictive set of patterns that include production of unicellular propagules and division into two similar size groups. Life cycles marked by single-cell bottlenecks maximise population growth rate under a wide range of conditions. This surprising result offers a new evolutionary explanation for the widespread occurrence of this mode of reproduction. All in all, our model provides a framework for exploring the adaptive significance of fragmentation modes and their associated life cycles.

  20. Fragmentation modes and the evolution of life cycles

    PubMed Central

    Rainey, Paul B.

    2017-01-01

    Reproduction is a defining feature of living systems. To reproduce, aggregates of biological units (e.g., multicellular organisms or colonial bacteria) must fragment into smaller parts. Fragmentation modes in nature range from binary fission in bacteria to collective-level fragmentation and the production of unicellular propagules in multicellular organisms. Despite this apparent ubiquity, the adaptive significance of fragmentation modes has received little attention. Here, we develop a model in which groups arise from the division of single cells that do not separate but stay together until the moment of group fragmentation. We allow for all possible fragmentation patterns and calculate the population growth rate of each associated life cycle. Fragmentation modes that maximise growth rate comprise a restrictive set of patterns that include production of unicellular propagules and division into two similar size groups. Life cycles marked by single-cell bottlenecks maximise population growth rate under a wide range of conditions. This surprising result offers a new evolutionary explanation for the widespread occurrence of this mode of reproduction. All in all, our model provides a framework for exploring the adaptive significance of fragmentation modes and their associated life cycles. PMID:29166656

  1. All-dielectric reflective half-wave plate metasurface based on the anisotropic excitation of electric and magnetic dipole resonances.

    PubMed

    Ma, Zhijie; Hanham, Stephen M; Gong, Yandong; Hong, Minghui

    2018-02-15

    We present an all-dielectric metasurface that simultaneously supports electric and magnetic dipole resonances for orthogonal polarizations. At resonances, the metasurface reflects the incident light with nearly perfect efficiency and provides a phase difference of π in the two axes, making a low-loss half-wave plate in reflection mode. The polarization handedness of the incident circularly polarized light is preserved after reflection; this is different from either a pure electric mirror or magnetic mirror. With the features of high reflection and circular polarization conservation, the metamirror is an ideal platform for the geometric phase-based gradient metasurface functioning in reflection mode. Anomalous reflection with the planar meta-mirror is demonstrated as a proof of concept. The proposed meta-mirror can be a good alternative to plasmonic metasurfaces for future compact and high-efficiency metadevices for polarization and phase manipulation in reflection mode.

  2. Half-time strategies to enhance second-half performance in team-sports players: a review and recommendations.

    PubMed

    Russell, Mark; West, Daniel J; Harper, Liam D; Cook, Christian J; Kilduff, Liam P

    2015-03-01

    A number of intermittent team sports require that two consecutive periods of play (lasting for ~30-45 min) are separated by a 10-20 min half-time break. The half-time practices employed by team-sports players generally include returning to the changing rooms, temporarily relaxing from the cognitive and physical demands of the first half, rehydration and re-fuelling strategies, addressing injury or equipment concerns, and receiving tactical instruction and coach feedback. However, the typically passive nature of these actions has been associated with physiological changes that impair performance during the second half. Both physical and cognitive performances have been found to decline in the initial stages of subsequent exercise that follows half-time. An increased risk of injury has also been observed during this period. Therefore, half-time provides sports scientists and strength and conditioning coaches with an opportunity to optimise second-half performance. An overview of strategies thought to benefit team-sports athletes is presented; specifically, the efficacy of heat maintenance strategies (including passive and active methods), post-activation potentiation, hormonal priming, and modified hydro-nutritional practices are discussed. A theoretical model of applying these strategies in a manner that compliments current practice is also offered.

  3. Synchronous Half-Wave Rectifier

    NASA Technical Reports Server (NTRS)

    Rippel, Wally E.

    1989-01-01

    Synchronous rectifying circuit behaves like diode having unusually low voltage drop during forward-voltage half cycles. Circuit particularly useful in power supplies with potentials of 5 Vdc or less, where normal forward-voltage drops in ordinary diodes unacceptably large. Fabricated as monolithic assembly or as hybrid. Synchronous half-wave rectifier includes active circuits to attain low forward voltage drop and high rectification efficiency.

  4. Influence of scan mode (180°/360°) of the cone beam computed tomography for preoperative dental implant measurements.

    PubMed

    Neves, Frederico S; Vasconcelos, Taruska V; Campos, Paulo S F; Haiter-Neto, Francisco; Freitas, Deborah Q

    2014-02-01

    The aim of this study was to evaluate the effect of scan mode of the cone beam computed tomography (CBCT) in the preoperative dental implant measurements. Completely edentulous mandibles with entirely resorbed alveolar processes were selected for this study. Five regions were selected (incisor, canine, premolar, first molar, and second molar). The mandibles were scanned with Next Generation i-CAT CBCT unit (Imaging Sciences International, Inc, Hatfield, PA, USA) with half (180°) and full (360°) mode. Two oral radiologists performed vertical measurements in all selected regions; the measurements of half of the sample were repeated within an interval of 30 days. The mandibles were sectioned using an electrical saw in all evaluated regions to obtain the gold standard. The intraclass correlation coefficient was calculated for the intra- and interobserver agreement. Descriptive statistics were calculated as mean, median, and standard deviation. Wilcoxon signed rank test was used to determine the correlation between the measurements obtained in different scan mode with the gold standard. The significance level was 5%. The values of intra- and interobserver reproducibility indicated a strong agreement. In the dental implant measurements, except the bone height of the second molar region in full scan mode (P = 0.02), the Wilcoxon signed rank test did not show statistical significant difference with the gold standard (P > 0.05). Both modes provided real measures, necessary when performing implant planning; however, half scan mode uses smaller doses, following the principle of effectiveness. We believe that this method should be used because of the best dose-effect relationship and offer less risk to the patient. © 2012 John Wiley & Sons A/S.

  5. Human Milk Bacterial and Glycosylation Patterns Differ by Delivery Mode.

    PubMed

    Hoashi, Marina; Meche, Lawrence; Mahal, Lara K; Bakacs, Elizabeth; Nardella, Deanna; Naftolin, Frederick; Bar-Yam, Naomi; Dominguez-Bello, Maria G

    2016-07-01

    Mammals have evolved to nourish their offspring exclusively with maternal milk for around half of the lactation period, a crucial developmental window. In view of oral-breast contact during lactation and the differences in oral microbiota between cesarean section (C-section) and vaginally delivered infants, we expected differences in milk composition by delivery mode. We performed a cross-sectional study of banked human milk and found changes related to time since delivery in bacterial abundance and glycosylation patterns only in milk from women who delivered vaginally. The results warrant further research into the effects of delivery mode on milk microbes, milk glycosylation, and postpartum infant development. © The Author(s) 2015.

  6. Full-wave and half-wave rectification in second-order motion perception

    NASA Technical Reports Server (NTRS)

    Solomon, J. A.; Sperling, G.

    1994-01-01

    Microbalanced stimuli are dynamic displays which do not stimulate motion mechanisms that apply standard (Fourier-energy or autocorrelational) motion analysis directly to the visual signal. In order to extract motion information from microbalanced stimuli, Chubb and Sperling [(1988) Journal of the Optical Society of America, 5, 1986-2006] proposed that the human visual system performs a rectifying transformation on the visual signal prior to standard motion analysis. The current research employs two novel types of microbalanced stimuli: half-wave stimuli preserve motion information following half-wave rectification (with a threshold) but lose motion information following full-wave rectification; full-wave stimuli preserve motion information following full-wave rectification but lose motion information following half-wave rectification. Additionally, Fourier stimuli, ordinary square-wave gratings, were used to stimulate standard motion mechanisms. Psychometric functions (direction discrimination vs stimulus contrast) were obtained for each type of stimulus when presented alone, and when masked by each of the other stimuli (presented as moving masks and also as nonmoving, counterphase-flickering masks). RESULTS: given sufficient contrast, all three types of stimulus convey motion. However, only one-third of the population can perceive the motion of the half-wave stimulus. Observers are able to process the motion information contained in the Fourier stimulus slightly more efficiently than the information in the full-wave stimulus but are much less efficient in processing half-wave motion information. Moving masks are more effective than counterphase masks at hampering direction discrimination, indicating that some of the masking effect is interference between motion mechanisms, and some occurs at earlier stages. When either full-wave and Fourier or half-wave and Fourier gratings are presented simultaneously, there is a wide range of relative contrasts within which the

  7. Modal density function and number of propagating modes in ducts

    NASA Technical Reports Server (NTRS)

    Rice, E. J.

    1976-01-01

    The question of the number of propagating modes within a small range of mode cut off ratio was raised. The population density of modes were shown to be greatest near cut off and least for the well propagating modes. It was shown that modes of nearly the same cut off ratio behave nearly the same in a sound absorbing duct as well as in the way they propagate to the far. Handling all of the propagating modes individually, they can be grouped into several cut off ratio ranges. It is important to know the modal density function to estimate acoustic power distribution.

  8. History of the Rochester Epidemiology Project: Half a Century of Medical Records Linkage in a US Population

    PubMed Central

    Rocca, Walter A.; Yawn, Barbara P.; St. Sauver, Jennifer L.; Grossardt, Brandon R.; Melton, L. Joseph

    2012-01-01

    The Rochester Epidemiology Project (REP) has maintained a comprehensive medical records linkage system for nearly half a century for almost all persons residing in Olmsted County, Minnesota. Herein, we provide a brief history of the REP before and after 1966, the year in which the REP was officially established. The key protagonists before 1966 were Henry Plummer, Mabel Root, and Joseph Berkson, who developed a medical records linkage system at Mayo Clinic. In 1966, Leonard Kurland established collaborative agreements with other local health care providers (hospitals, physician groups, and clinics [primarily Olmsted Medical Center]) to develop a medical records linkage system that covered the entire population of Olmsted County, and he obtained funding from the National Institutes of Health to support the new system. In 1997, L. Joseph Melton III addressed emerging concerns about the confidentiality of medical record information by introducing a broad patient research authorization as per Minnesota state law. We describe how the key protagonists of the REP have responded to challenges posed by evolving medical knowledge, information technology, and public expectation and policy. In addition, we provide a general description of the system; discuss issues of data quality, reliability, and validity; describe the research team structure; provide information about funding; and compare the REP with other medical information systems. The REP can serve as a model for the development of similar research infrastructures in the United States and worldwide. PMID:23199802

  9. A mathematical model of avian influenza with half-saturated incidence.

    PubMed

    Chong, Nyuk Sian; Tchuenche, Jean Michel; Smith, Robert J

    2014-03-01

    The widespread impact of avian influenza viruses not only poses risks to birds, but also to humans. The viruses spread from birds to humans and from human to human In addition, mutation in the primary strain will increase the infectiousness of avian influenza. We developed a mathematical model of avian influenza for both bird and human populations. The effect of half-saturated incidence on transmission dynamics of the disease is investigated. The half-saturation constants determine the levels at which birds and humans contract avian influenza. To prevent the spread of avian influenza, the associated half-saturation constants must be increased, especially the half-saturation constant H m for humans with mutant strain. The quantity H m plays an essential role in determining the basic reproduction number of this model. Furthermore, by decreasing the rate β m at which human-to-human mutant influenza is contracted, an outbreak can be controlled more effectively. To combat the outbreak, we propose both pharmaceutical (vaccination) and non-pharmaceutical (personal protection and isolation) control methods to reduce the transmission of avian influenza. Vaccination and personal protection will decrease β m, while isolation will increase H m. Numerical simulations demonstrate that all proposed control strategies will lead to disease eradication; however, if we only employ vaccination, it will require slightly longer to eradicate the disease than only applying non-pharmaceutical or a combination of pharmaceutical and non-pharmaceutical control methods. In conclusion, it is important to adopt a combination of control methods to fight an avian influenza outbreak.

  10. Disorder-induced half-integer quantized conductance plateau in quantum anomalous Hall insulator-superconductor structures

    NASA Astrophysics Data System (ADS)

    Huang, Yingyi; Setiawan, F.; Sau, Jay D.

    2018-03-01

    A weak superconducting proximity effect in the vicinity of the topological transition of a quantum anomalous Hall system has been proposed as a venue to realize a topological superconductor (TSC) with chiral Majorana edge modes (CMEMs). A recent experiment [Science 357, 294 (2017), 10.1126/science.aag2792] claimed to have observed such CMEMs in the form of a half-integer quantized conductance plateau in the two-terminal transport measurement of a quantum anomalous Hall-superconductor junction. Although the presence of a superconducting proximity effect generically splits the quantum Hall transition into two phase transitions with a gapped TSC in between, in this Rapid Communication we propose that a nearly flat conductance plateau, similar to that expected from CMEMs, can also arise from the percolation of quantum Hall edges well before the onset of the TSC or at temperatures much above the TSC gap. Our Rapid Communication, therefore, suggests that, in order to confirm the TSC, it is necessary to supplement the observation of the half-quantized conductance plateau with a hard superconducting gap (which is unlikely for a disordered system) from the conductance measurements or the heat transport measurement of the transport gap. Alternatively, the half-quantized thermal conductance would also serve as a smoking-gun signature of the TSC.

  11. Plasmonic Photovoltaic Cells with Dual-Functional Gold, Silver, and Copper Half-Shell Arrays.

    PubMed

    Wu, Ling; Kim, Gyu Min; Nishi, Hiroyasu; Tatsuma, Tetsu

    2017-09-12

    Solid-state photovoltaic cells based on plasmon-induced charge separation (PICS) have attracted growing attention during the past decade. However, the power conversion efficiency (PCE) of the previously reported devices, which are generally loaded with dispersed metal nanoparticles as light absorbers, has not been sufficiently high. Here we report simpler plasmonic photovoltaic cells with interconnected Au, Ag, and Cu half-shell arrays deposited on SiO 2 @TiO 2 colloidal crystals, which serve both as a plasmonic light absorber and as a current collector. The well-controlled and easily prepared plasmonic structure allows precise comparison of the PICS efficiency between different plasmonic metal species. The cell with the Ag half-shell array has higher photovoltaic performance than the cells with Au and Cu half-shell arrays because of the high population of photogenerated energetic electrons, which gives a high electron injection efficiency and suppressed charge recombination probability, achieving the highest PCE among the solid-state PICS devices even without a hole transport layer.

  12. 7 CFR 51.1441 - Half-kernel.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Half-kernel. 51.1441 Section 51.1441 Agriculture... Standards for Grades of Shelled Pecans Definitions § 51.1441 Half-kernel. Half-kernel means one of the separated halves of an entire pecan kernel with not more than one-eighth of its original volume missing...

  13. On the half-life of luminescence signals in dosimetric applications: A unified presentation

    NASA Astrophysics Data System (ADS)

    Pagonis, V.; Kitis, G.; Polymeris, G. S.

    2018-06-01

    Luminescence signals from natural and man-made materials are widely used in dosimetric and dating applications. In general, there are two types of half-lives of luminescence signals which are of importance to experimental and modeling work in this research area. The first type of half-life is the time required for the population of the trapped charge in a single trap to decay to half its initial value. The second type of half-life is the time required for the luminescence intensity to drop to half of its initial value. While there a handful of analytical expressions available in the literature for the first type of half-life, there are no corresponding analytical expressions for the second type. In this work new analytical expressions are derived for the half-life of luminescence signals during continuous wave optical stimulation luminescence (CW-OSL) or isothermal luminescence (ITL) experiments. The analytical expressions are derived for several commonly used luminescence models which are based on delocalized transitions involving the conduction band: first and second order kinetics, empirical general order kinetics (GOK), mixed order kinetics (MOK) and the one-trap one-recombination center (OTOR) model. In addition, half-life expressions are derived for a different type of luminescence model, which is based on localized transitions in a random distribution of charges. The new half-life expressions contain two parts. The first part is inversely proportional to the thermal or optical excitation rate, and depends on the experimental conditions and on the cross section of the relevant luminescence process. The second part is characteristic of the optical and/or thermal properties of the material, as expressed by the parameters in the model. A new simple and quick method for analyzing luminescence signals is developed, and examples are given of applying the new method to a variety of dosimetric materials. The new test allows quick determination of whether a set of

  14. The Development of CyberLearning in Dual-Mode: Higher Education Institutions in Taiwan.

    ERIC Educational Resources Information Center

    Chen, Yau Jane

    2002-01-01

    Open and distance education in Taiwan has evolved into cyberlearning. Over half (56 percent) of the conventional universities and colleges have been upgraded to dual-mode institutions offering real-time multicast instructional systems using videoconferencing, cable television, virtual classrooms, and curriculum-on-demand systems. The Ministry of…

  15. 76 FR 37641 - Safety Zone; Independence Day Fireworks Celebration for the City of Half Moon Bay, Half Moon Bay, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-28

    ...-AA00 Safety Zone; Independence Day Fireworks Celebration for the City of Half Moon Bay, Half Moon Bay... temporary safety zone in the navigable waters of Half Moon Bay, off of Pillar Point Harbor beach, Half Moon Bay, CA in support of the Independence Day Fireworks Celebration for the City of Half Moon Bay...

  16. Preserving flying qubit in single-mode fiber with Knill Dynamical Decoupling (KDD)

    NASA Astrophysics Data System (ADS)

    Gupta, Manish; Navarro, Erik; Moulder, Todd; Mueller, Jason; Balouchi, Ashkan; Brown, Katherine; Lee, Hwang; Dowling, Jonathan

    2015-03-01

    The implementation of information-theoretic-crypto protocol is limited by decoherence caused by the birefringence of a single-mode fiber. We propose the Knill dynamical decoupling scheme, implemented using half-wave plates, to minimize decoherence and show that a fidelity greater than 96% can be achieved even in presence of rotation error.

  17. Metric half-span model support system

    NASA Technical Reports Server (NTRS)

    Jackson, C. M., Jr.; Dollyhigh, S. M.; Shaw, D. S. (Inventor)

    1982-01-01

    A model support system used to support a model in a wind tunnel test section is described. The model comprises a metric, or measured, half-span supported by a nonmetric, or nonmeasured half-span which is connected to a sting support. Moments and forces acting on the metric half-span are measured without interference from the support system during a wind tunnel test.

  18. Photoacoustic image reconstruction from ultrasound post-beamformed B-mode image

    NASA Astrophysics Data System (ADS)

    Zhang, Haichong K.; Guo, Xiaoyu; Kang, Hyun Jae; Boctor, Emad M.

    2016-03-01

    A requirement to reconstruct photoacoustic (PA) image is to have a synchronized channel data acquisition with laser firing. Unfortunately, most clinical ultrasound (US) systems don't offer an interface to obtain synchronized channel data. To broaden the impact of clinical PA imaging, we propose a PA image reconstruction algorithm utilizing US B-mode image, which is readily available from clinical scanners. US B-mode image involves a series of signal processing including beamforming, followed by envelope detection, and end with log compression. Yet, it will be defocused when PA signals are input due to incorrect delay function. Our approach is to reverse the order of image processing steps and recover the original US post-beamformed radio-frequency (RF) data, in which a synthetic aperture based PA rebeamforming algorithm can be further applied. Taking B-mode image as the input, we firstly recovered US postbeamformed RF data by applying log decompression and convoluting an acoustic impulse response to combine carrier frequency information. Then, the US post-beamformed RF data is utilized as pre-beamformed RF data for the adaptive PA beamforming algorithm, and the new delay function is applied by taking into account that the focus depth in US beamforming is at the half depth of the PA case. The feasibility of the proposed method was validated through simulation, and was experimentally demonstrated using an acoustic point source. The point source was successfully beamformed from a US B-mode image, and the full with at the half maximum of the point improved 3.97 times. Comparing this result to the ground-truth reconstruction using channel data, the FWHM was slightly degraded with 1.28 times caused by information loss during envelope detection and convolution of the RF information.

  19. Longitudinal mode selection in a delay-line homogeneously broadened oscillator with a fast saturable amplifier.

    PubMed

    Fleyer, Michael; Horowitz, Moshe

    2017-05-01

    Homogeneously broadened delay-line oscillators such as lasers or optoelectronic oscillators (OEOs) can potentially oscillate in a large number of cavity modes that are supported by their amplifier bandwidth. In a continuous wave operating mode, the oscillating mode is selected between one or few cavity modes that experience the highest small-signal gain. In this manuscript, we show that the oscillation mode of a homogeneously broadened oscillator can be selected from a large number of modes in a frequency region that can be broader than the full width at half maximum of the effective cavity filter. The mode is selected by a short-time injection of an external signal into the oscillator. After the external signal is turned off, the oscillation is maintained in the selected mode even if this mode has a significantly lower small-signal gain than that of other cavity modes. The stability of the oscillation is obtained due to nonlinear saturation effect in the oscillator amplifier. We demonstrate, experimentally and theoretically, mode selection in a long cavity OEO. We could select any desired mode between 400 cavity modes while maintaining ultra-low phase noise in the selected mode and in the non-oscillating modes. No mode-hopping was observed during our maximum measurement duration of about 24 hours.

  20. Excitation of half-integer up-shifted decay channel and quasi-mode in plasma edge for high power electron Bernstein wave heating scenario

    NASA Astrophysics Data System (ADS)

    Ali Asgarian, M.; Abbasi, M.

    2018-04-01

    Electron Bernstein waves (EBW) consist of promising tools in driving localized off-axis current needed for sustained operation as well as effective selective heating scenarios in advanced over dense fusion plasmas like spherical tori and stellarators by applying high power radio frequency waves within the range of Megawatts. Here some serious non-linear effects like parametric decay modes are highly expect-able which have been extensively studied theoretically and experimentally. In general, the decay of an EBW depends on the ratio of the incident frequency and electron cyclotron frequency. At ratios less than two, parametric decay leads to a lower hybrid wave (or an ion Bernstein wave) and EBWs at a lower frequency. For ratios more than two, the daughter waves constitute either an electron cyclotron quasi-mode and another EBW or an ion wave and EBW. However, in contrast with these decay patterns, the excitation of an unusual up-shifted frequency decay channel for the ratio less than two is demonstrated in this study which is totally different as to its generation and persistence. It is shown that this mode varies from the conventional parametric decay channels which necessarily satisfy the matching conditions in frequency and wave-vector. Moreover, the excitation of some less-known local non-propagating quasi-modes (virtual modes) through weak-turbulence theory and their contributions to energy leakage from conversion process leading the reduction in conversion efficiency is assessed.

  1. Electronic transport across a junction between armchair graphene nanotube and zigzag nanoribbon. Transmission in an armchair nanotube without a zigzag half-line of dimers

    NASA Astrophysics Data System (ADS)

    Sharma, Basant Lal

    2018-05-01

    Based on the well known nearest-neighbor tight-binding approximation for graphene, an exact expression for the electronic conductance across a zigzag nanoribbon/armchair nanotube junction is presented for non-interacting electrons. The junction results from the removal of a half-row of zigzag dimers in armchair nanotube, or equivalently by partial rolling of zigzag nanoribbon and insertion of a half-row of zigzag dimers in between. From the former point of view, a discrete form of Dirichlet condition is imposed on a zigzag half-line of dimers assuming the vanishing of wave function outside the physical structure. A closed form expression is provided for the reflection and transmission moduli for the outgoing wave modes for each given electronic wave mode incident from either side of the junction. It is demonstrated that such a contact junction between the nanotube and nanoribbon exhibits negligible backscattering, and the transmission has been found to be nearly ballistic. In contrast to the previously reported studies for partially unzipped carbon nanotubes (CNTs), using the same tight binding model, it is found that due to the "defect" there is certain amount of mixing between the electronic wave modes with even and odd reflection symmetries. But the junction remains a perfect valley filter for CNTs at certain energy ranges. Applications aside from the electronic case, include wave propagation in quasi-one-dimensional honeycomb structures of graphene-like constitution. The paper includes several numerical calculations, analytical derivations, and graphical results, which complement the provision of succinct closed form expressions.

  2. Half-Cell RF Gun Simulations with the Electromagnetic Particle-in-Cell Code VORPAL

    NASA Astrophysics Data System (ADS)

    Paul, K.; Dimitrov, D. A.; Busby, R.; Bruhwiler, D. L.; Smithe, D.; Cary, J. R.; Kewisch, J.; Kayran, D.; Calaga, R.; Ben-Zvi, I.

    2009-01-01

    We have simulated Brookhaven National Laboratory's half-cell superconducting RF gun design for a proposed high-current ERL using the three-dimensional, electromagnetic particle-in-cell code VORPAL. VORPAL computes the fully self-consistent electromagnetic fields produced by the electron bunches, meaning that it accurately models space-charge effects as well as bunch-to-bunch beam loading effects and the effects of higher-order cavity modes, though these are beyond the scope of this paper. We compare results from VORPAL to the well-established space-charge code PARMELA, using RF fields produced by SUPERFISH, as a benchmarking exercise in which the two codes should agree well.

  3. Combining BRITE and ground-based photometry for the β Cephei star ν Eridani: impact on photometric pulsation mode identification and detection of several g modes

    NASA Astrophysics Data System (ADS)

    Handler, G.; Rybicka, M.; Popowicz, A.; Pigulski, A.; Kuschnig, R.; Zocłońska, E.; Moffat, A. F. J.; Weiss, W. W.; Grant, C. C.; Pablo, H.; Whittaker, G. N.; Ruciński, S. M.; Ramiaramanantsoa, T.; Zwintz, K.; Wade, G. A.

    2017-01-01

    We report a simultaneous ground- and space-based photometric study of the β Cephei star ν Eridani. Half a year of observations have been obtained by four of the five satellites constituting BRITE-Constellation, supplemented with ground-based photoelectric photometry. We show that carefully combining the two data sets virtually eliminates the aliasing problem that often hampers time series analyses. We detect 40 periodic signals intrinsic to the star in the light curves. Despite a lower detection limit, we do not recover all the pressure and mixed modes previously reported in the literature, but we newly detect six additional gravity modes. This behaviour is a consequence of temporal changes in the pulsation amplitudes that we also detected for some of the p modes. We point out that the dependence of theoretically predicted pulsation amplitude on wavelength is steeper in visual passbands than those observationally measured, to the extent that three dominant pulsation modes of ν Eridani would be incorrectly identified using data in optical filters only. We discuss possible reasons for this discrepancy.

  4. Measurement of the double-{beta} decay half-life of {sup 150}Nd and search for neutrinoless decay modes with the NEMO-3 detector

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

    Argyriades, J.; Augier, C.; Bongrand, M.

    2009-09-15

    The half-life for double-{beta} decay of {sup 150}Nd has been measured by the NEMO-3 experiment at the Modane Underground Laboratory. Using 924.7 days of data recorded with 36.55 g of {sup 150}Nd, we measured the half-life for 2{nu}{beta}{beta} decay to be T{sub 1/2}{sup 2{nu}}=(9.11{sub -0.22}{sup +0.25}(stat.){+-}0.63(syst.))x10{sup 18} yr. The observed limit on the half-life for neutrinoless double-{beta} decay is found to be T{sub 1/2}{sup 0{nu}}>1.8x10{sup 22} yr at 90% confidence level. This translates into a limit on the effective Majorana neutrino mass of <4.0-6.3 eV if the nuclear deformation is taken into account. We also set limits on modelsmore » involving Majoron emission, right-handed currents, and transitions to excited states.« less

  5. Temporal genetic structure in a poecilogonous polychaete: the interplay of developmental mode and environmental stochasticity

    PubMed Central

    2014-01-01

    Background Temporal variation in the genetic structure of populations can be caused by multiple factors, including natural selection, stochastic environmental variation, migration, or genetic drift. In benthic marine species, the developmental mode of larvae may indicate a possibility for temporal genetic variation: species with dispersive planktonic larvae are expected to be more likely to show temporal genetic variation than species with benthic or brooded non-dispersive larvae, due to differences in larval mortality and dispersal ability. We examined temporal genetic structure in populations of Pygospio elegans, a poecilogonous polychaete with within-species variation in developmental mode. P. elegans produces either planktonic, benthic, or intermediate larvae, varying both among and within populations, providing a within-species test of the generality of a relationship between temporal genetic variation and larval developmental mode. Results In contrast to our expectations, our microsatellite analyses of P. elegans revealed temporal genetic stability in the UK population with planktonic larvae, whereas there was variation indicative of drift in temporal samples of the populations from the Baltic Sea, which have predominantly benthic and intermediate larvae. We also detected temporal variation in relatedness within these populations. A large temporal shift in genetic structure was detected in a population from the Netherlands, having multiple developmental modes. This shift could have been caused by local extiction due to extreme environmental conditions and (re)colonization by planktonic larvae from neighboring populations. Conclusions In our study of P. elegans, temporal genetic variation appears to be due to not only larval developmental mode, but also the stochastic environment of adults. Large temporal genetic shifts may be more likely in marine intertidal habitats (e.g. North Sea and Wadden Sea) which are more prone to environmental stochasticity than the

  6. Temporal genetic structure in a poecilogonous polychaete: the interplay of developmental mode and environmental stochasticity.

    PubMed

    Kesäniemi, Jenni E; Mustonen, Marina; Boström, Christoffer; Hansen, Benni W; Knott, K Emily

    2014-01-22

    Temporal variation in the genetic structure of populations can be caused by multiple factors, including natural selection, stochastic environmental variation, migration, or genetic drift. In benthic marine species, the developmental mode of larvae may indicate a possibility for temporal genetic variation: species with dispersive planktonic larvae are expected to be more likely to show temporal genetic variation than species with benthic or brooded non-dispersive larvae, due to differences in larval mortality and dispersal ability. We examined temporal genetic structure in populations of Pygospio elegans, a poecilogonous polychaete with within-species variation in developmental mode. P. elegans produces either planktonic, benthic, or intermediate larvae, varying both among and within populations, providing a within-species test of the generality of a relationship between temporal genetic variation and larval developmental mode. In contrast to our expectations, our microsatellite analyses of P. elegans revealed temporal genetic stability in the UK population with planktonic larvae, whereas there was variation indicative of drift in temporal samples of the populations from the Baltic Sea, which have predominantly benthic and intermediate larvae. We also detected temporal variation in relatedness within these populations. A large temporal shift in genetic structure was detected in a population from the Netherlands, having multiple developmental modes. This shift could have been caused by local extiction due to extreme environmental conditions and (re)colonization by planktonic larvae from neighboring populations. In our study of P. elegans, temporal genetic variation appears to be due to not only larval developmental mode, but also the stochastic environment of adults. Large temporal genetic shifts may be more likely in marine intertidal habitats (e.g. North Sea and Wadden Sea) which are more prone to environmental stochasticity than the sub-tidal Baltic habitats. Sub

  7. Photoinduced half-integer quantized conductance plateaus in topological-insulator/superconductor heterostructures

    NASA Astrophysics Data System (ADS)

    Yap, Han Hoe; Zhou, Longwen; Lee, Ching Hua; Gong, Jiangbin

    2018-04-01

    The past few years have witnessed increased attention to the quest for Majorana-like excitations in the condensed matter community. As a promising candidate in this race, the one-dimensional chiral Majorana edge mode (CMEM) in topological insulator-superconductor heterostructures has gathered renewed interests after an experimental breakthrough [Q. L. He et al., Science 357, 294 (2017), 10.1126/science.aag2792]. In this work, we study computationally the quantum transport of topological insulator-superconductor hybrid devices subject to time-periodic modulation. We report half-integer quantized conductance plateaus at 1/2 e/2h and 3/2 e/2h upon applying the so-called sum rule in the theory of quantum transport in Floquet topological matter. In particular, in a photoinduced topological superconductor sandwiched between two Floquet Chern insulators, it is found that for each Floquet sideband, the CMEM admits equal probability for normal transmission and local Andreev reflection over a wide range of parameter regimes, yielding half-integer quantized plateaus that resist static and time-periodic disorder. While it is well-established that periodic driving fields can simultaneously create and manipulate multiple pairs of Majorana bound states, their detection scheme remains elusive, in part due to their being neutral excitations. Therefore the 3/2 e/2h plateau indicates the possibility to verify the generation of multiple pairs of photoinduced CMEMs via transport measurements. The robust and half-quantized conductance plateaus due to CMEMs are both fascinating and subtle because they only emerge after a summation over contributions from all Floquet sidebands. Our work may add insights into the transport properties of Floquet topological systems and stimulate further studies on the optical control of topological superconductivity.

  8. [Evaluation of the 2.5 mg fentanyl patch, applied using the half-side application procedure in patients with cancer pain].

    PubMed

    Kokubun, Hideya; Matoba, Motohiro; Okazaki, Miyoko; Hoka, Sumio; Yago, Kazuo

    2008-03-01

    Occasionally, pain control with the fentanyl patch may lead to overdose at an initial dose of 2.5 mg, as well as during dose increase from 2.5 to 5.0 mg. Respiratory depression and other adverse drug reactions associated with fentanyl overdose have been observed in several of our patients. We developed a procedure for applying one-half of the fentanyl patch formulations and evaluated the new mode of application by examining the fentanyl concentration in 32 patients with cancer-related pain who had been using the fentanyl patch for pain control. While some patients were treated with the full-sized 2.5-, 5.0-, or 7.5-mg formulations, others were treated with the half-sized 2.5-mg formulation. The fentanyl patch was equally divided by drawing a line on the side on which the product name and dose were written. Tegaderm was applied to the patient's skin, and after detaching from the protective liner, half of the patch was applied to overlap Tegaderm along the line and the other half applied directly to the skin. Blood samples were collected 48-72 h after patch application. The mean serum concentration of fentanyl given in the half-sized 2.5-mg formulation was 0.286 ng/ml, which was approximately one-half of the concentration of the full-sized 2.5-mg formulation, 0.544 ng/ml. Therefore the 2.5-mg fentanyl patch, applied using the one-half procedure we developed, is clinically useful.

  9. Three distinct modes in a surface micro-discharge in atmospheric pressure He + N{sub 2} mixtures

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

    Li, Dong; Liu, Dingxin, E-mail: liudingxin@mail.xjtu.edu.cn; He, Tongtong

    2015-12-15

    A surface micro-discharge in atmospheric pressure He + N{sub 2} mixtures is studied in this paper with an emphasis on the discharge modes. With the N{sub 2} admixture increasing from 0.1% to 20%, the discharge evolves from a spatially diffuse mode to a filamentary mode during positive half-cycles of the applied voltage. However during the negative half-cycles, an additional patterned mode emerges between the diffuse and the filamentary modes, which has not been reported before to exist in surface micro-discharges. In the diffuse and patterned modes, the plasmas cover almost the entirety of the mesh area during one cycle after plasma ignitionmore » in all mesh elements, and the discharge power increases linearly with the applied voltage. In contrast, plasma coverage of the mesh area is only partial in the filamentary mode and the plasma is more unstable with the discharge power increasing exponentially with the applied voltage. As the surface micro-discharge evolves through the three modes, the density of excited species changes significantly, for instance, the density of N{sub 2}{sup +}(B) drops by ∼20-fold from [N{sub 2}] = 0.2% to 20%. The N{sub 2}{sup +}(B) is predicted to be generated mainly through successive processes of Penning ionization by helium metastables and electron-impact excitation of N{sub 2}{sup +}(X), the latter is most responsible for the density decrease of N{sub 2}{sup +}(B) because much more N{sub 2}{sup +}(X) is converted to N{sub 4}{sup +}(X) as the increase of N{sub 2} fraction. Also, the electron density and electron temperature decrease with the discharge mode transition.« less

  10. Modifications to JLab 12 GeV Refrigerator and Wide Range Mix Mode Performance Testing Results

    NASA Astrophysics Data System (ADS)

    Knudsen, P.; Ganni, V.; Hasan, N.; Dixon, K.; Norton, R.; Creel, J.

    2017-02-01

    Analysis of data obtained during the spring 2013 commissioning of the new 4.5 K refrigeration system at Jefferson Lab (JLab) for the 12 GeV upgrade indicated a wide capacity range with good efficiency and minimal operator interaction. Testing also showed that the refrigerator required higher liquid nitrogen (LN) consumption for its pre-cooler than anticipated by the design. This does not affect the capacity of the refrigerator, but it does result in an increased LN utility cost. During the summer of 2015 the modifications were implemented by the cold box manufacturer, according to a design similar to the JLab 12 GeV cold box specification. Subsequently, JLab recommissioned the cold box and performed extensive performance testing, ranging from 20% to 100% of the design maximum capacity, and in various modes of operation, ranging from pure refrigeration, pure liquefaction, half-and-half mix mode and at selected design modes using the Floating Pressure - Ganni Cycle. The testing demonstrated that the refrigerator system has a good and fairly constant performance over a wide capacity range and different modes of operation. It also demonstrated the modifications resulted in a LN consumption that met the design for the pure refrigeration mode (which is the most demanding) and was lower than the design for the nominal and maximum capacity modes. In addition, a pulsed-load test, similar to what is expected for cryogenic systems supporting fusion experiments, was conducted to observe the response using the Floating Pressure - Ganni Cycle, which was stable and robust. This paper will discuss the results and analysis of this testing pertaining to the LN consumption, the system efficiency over a wide range of capacity and different modes and the behaviour of the system to a pulsed load.

  11. History of the Rochester Epidemiology Project: half a century of medical records linkage in a US population.

    PubMed

    Rocca, Walter A; Yawn, Barbara P; St Sauver, Jennifer L; Grossardt, Brandon R; Melton, L Joseph

    2012-12-01

    The Rochester Epidemiology Project (REP) has maintained a comprehensive medical records linkage system for nearly half a century for almost all persons residing in Olmsted County, Minnesota. Herein, we provide a brief history of the REP before and after 1966, the year in which the REP was officially established. The key protagonists before 1966 were Henry Plummer, Mabel Root, and Joseph Berkson, who developed a medical records linkage system at Mayo Clinic. In 1966, Leonard Kurland established collaborative agreements with other local health care providers (hospitals, physician groups, and clinics [primarily Olmsted Medical Center]) to develop a medical records linkage system that covered the entire population of Olmsted County, and he obtained funding from the National Institutes of Health to support the new system. In 1997, L. Joseph Melton III addressed emerging concerns about the confidentiality of medical record information by introducing a broad patient research authorization as per Minnesota state law. We describe how the key protagonists of the REP have responded to challenges posed by evolving medical knowledge, information technology, and public expectation and policy. In addition, we provide a general description of the system; discuss issues of data quality, reliability, and validity; describe the research team structure; provide information about funding; and compare the REP with other medical information systems. The REP can serve as a model for the development of similar research infrastructures in the United States and worldwide. Copyright © 2012 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  12. A half-metallic half-Heusler alloy having the largest atomic-like magnetic moment at optimized lattice constant

    DOE PAGES

    Zhang, R. L.; Damewood, L.; Fong, C. Y.; ...

    2016-11-02

    For half-Heusler alloys, the general formula is XYZ, where X can be a transition or alkali metal element, Y is another transition metal element, typically Mn or Cr, and Z is a group IV element or a pnicitide. The atomic arrangements within a unit-cell show three configurations. Before this study, most of the predictions of half-metallic properties of half-Heusler alloys at the lattice constants differing from their optimized lattice constant. Based on the electropositivity of X and electronegativity of Z for half-Heusler alloys, we found that one of the configurations of LiCrS exhibits half-metallic properties at its optimized lattice constantmore » of 5.803Å, and has the maximum atomic-like magnetic moment of 5μ B. In conclusion, the challenges of its growth and the effects of the spin-orbit effect in this alloy will be discussed.« less

  13. The analysis of predictability of recent alpha decay formulae and the alpha partial half-lives of some exotic nuclei

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

    Dasgupta-Schubert, N.; Reyes, M. A.; Tamez, V. A.

    2009-04-20

    Alpha decay is one of the two main decay modes of the heaviest nuclei, (SHE), and constitutes one of the dominant decay modes of highly neutron deficient medium mass nuclei ('exotics'). Thus identifying and characterizing the alpha decay chains form a crucial part of the identification of SHE. We report the extension of the previously developed method for the detailed and systematic investigation of the reliability of the three main extant analytical formulae of alpha decay half-lives: the generalized liquid drop model based formula of Royer et al. (FR), the Sobiczewski modified semi-empirical Viola-Seaborg formula (VSS) and the recent phenomenologicalmore » formula of Sobiczewski and Parkhomenko (SP)« less

  14. Commuting mode and pulmonary function in Shanghai, China

    PubMed Central

    Gaffney, Adam W.; Hang, Jing-qing; Lee, Mi-Sun; Su, Li; Zhang, Fengying; Christiani, David C.

    2016-01-01

    Introduction Exposure to air pollution can be particularly high during commuting, and may depend on the mode of transportation. We investigated the impact of commuting mode on pulmonary function in Shanghai, China. Material and methods The Shanghai Putuo Study is a cross-sectional population-based study. Our primary outcomes were FEV1 and FVC percent predicted, and the secondary outcome was spirometric airflow obstruction. We tested the association between mode of transportation and these outcomes after adjusting for confounders. Results The study population consisted of 20,102 subjects. After adjusting for confounders, the FEV1 percent predicted was 2.15 lower (95% CI −2.88, −1.42) among walkers, 1.32 lower (95% CI −2.05, −0.59) among those taking buses without air-conditioning, 1.33 lower (95% CI −2.05, −0.61) among those taking buses with air-conditioning, and 2.83 lower (95% CI −5.56, −0.10) among subway-riders, as compared to cyclists (the reference group). The effects of mode on FVC percent predicted were in the same direction. Private car use had a significant protective effect on FVC percent predicted and the risk of airflow obstruction (defined by GOLD but not by LLN criteria). Conclusions Mode of transportation is associated with differences in lung function, which may reflect pollution levels in different transportation microenvironments. PMID:26541519

  15. Chirping and Sudden Excitation of Energetic-Particle-Driven Geodesic Acoustic Modes in a Large Helical Device Experiment

    NASA Astrophysics Data System (ADS)

    Wang, Hao; Todo, Yasushi; Ido, Takeshi; Suzuki, Yasuhiro

    2018-04-01

    Energetic-particle-driven geodesic acoustic modes (EGAMs) observed in a Large Helical Device experiment are investigated using a hybrid simulation code for energetic particles interacting with a magnetohydrodynamic (MHD) fluid. The frequency chirping of the primary mode and the sudden excitation of the half-frequency secondary mode are reproduced for the first time with the hybrid simulation using the realistic physical condition and the three-dimensional equilibrium. Both EGAMs have global spatial profiles which are consistent with the experimental measurements. For the secondary mode, the bulk pressure perturbation and the energetic particle pressure perturbation cancel each other out, and thus the frequency is lower than the primary mode. It is found that the excitation of the secondary mode does not depend on the nonlinear MHD coupling. The secondary mode is excited by energetic particles that satisfy the linear and nonlinear resonance conditions, respectively, for the primary and secondary modes.

  16. Chirping and Sudden Excitation of Energetic-Particle-Driven Geodesic Acoustic Modes in a Large Helical Device Experiment.

    PubMed

    Wang, Hao; Todo, Yasushi; Ido, Takeshi; Suzuki, Yasuhiro

    2018-04-27

    Energetic-particle-driven geodesic acoustic modes (EGAMs) observed in a Large Helical Device experiment are investigated using a hybrid simulation code for energetic particles interacting with a magnetohydrodynamic (MHD) fluid. The frequency chirping of the primary mode and the sudden excitation of the half-frequency secondary mode are reproduced for the first time with the hybrid simulation using the realistic physical condition and the three-dimensional equilibrium. Both EGAMs have global spatial profiles which are consistent with the experimental measurements. For the secondary mode, the bulk pressure perturbation and the energetic particle pressure perturbation cancel each other out, and thus the frequency is lower than the primary mode. It is found that the excitation of the secondary mode does not depend on the nonlinear MHD coupling. The secondary mode is excited by energetic particles that satisfy the linear and nonlinear resonance conditions, respectively, for the primary and secondary modes.

  17. Dual-fuel, dual-mode rocket engine

    NASA Technical Reports Server (NTRS)

    Martin, James A. (Inventor)

    1989-01-01

    The invention relates to a dual fuel, dual mode rocket engine designed to improve the performance of earth-to-orbit vehicles. For any vehicle that operates from the earth's surface to earth orbit, it is advantageous to use two different fuels during its ascent. A high density impulse fuel, such as kerosene, is most efficient during the first half of the trajectory. A high specific impulse fuel, such as hydrogen, is most efficient during the second half of the trajectory. The invention allows both fuels to be used with a single rocket engine. It does so by adding a minimum number of state-of-the-art components to baseline single made rocket engines, and is therefore relatively easy to develop for near term applications. The novelty of this invention resides in the mixing of fuels before exhaust nozzle cooling. This allows all of the engine fuel to cool the exhaust nozzle, and allows the ratio of fuels used throughout the flight depend solely on performance requirements, not cooling requirements.

  18. Prehension of Half-Full and Half-Empty Glasses: Time and History Effects on Multi-Digit Coordination

    PubMed Central

    Sun, Yao; Zatsiorsky, Vladimir M.; Latash, Mark L.

    2011-01-01

    We explored how digit forces and indices of digit coordination depend on the history of getting to a particular set of task parameters during static prehension tasks. The participants held in the right hand an instrumented handle with a light-weight container attached on top of the handle. At the beginning of each trial, the container could be empty, filled to the half with water (0.4 l) or filled to the top (0.8 l). The water was pumped in/out of the container at a constant, slow rate over 10 s. At the end of each trial, the participants always held a half-filled container that has just been filled (Empty-Half), emptied (Full-Half), or stayed half-filled throughout the trial (Half-Only). Indices of co-variation (synergy indices) of elemental variables (forces and moments of force produced by individual digits) stabilizing such performance variables as total normal force, total tangetial force, and total moment of force were computed at two levels of an assumed control hierarchy. At the upper level, the task is shared between the thumb and virtual finger (an imagined digit with the mechanical action equal to that of the four fingers), while at the lower level, action of the virtual finger is shared among the actual four fingers. Filling or emptying the container led to a drop in the safety margin (proportion of grip force over the slipping threshold) below the values observed in the Half-Only condition. Synergy indices at both levels of the hierarchy showed changes over the Full-Half and Empty-Half condition. These changes could be monotonic (typical of moment of force and normal force) or non-monotonic (typical of tangential force). For both normal and tangential forces, higher synergy indices at the higher level of the hierarchy corresponded to lower indices at the lower level. Significant differences in synergy indices across conditions were seen at the final steady-state showing that digit coordination during steady holding an object is history dependent. The

  19. Computing the Dynamic Response of a Stratified Elastic Half Space Using Diffuse Field Theory

    NASA Astrophysics Data System (ADS)

    Sanchez-Sesma, F. J.; Perton, M.; Molina Villegas, J. C.

    2015-12-01

    The analytical solution for the dynamic response of an elastic half-space for a normal point load at the free surface is due to Lamb (1904). For a tangential force, we have Chaós (1960) formulae. For an arbitrary load at any depth within a stratified elastic half space, the resulting elastic field can be given in the same fashion, by using an integral representation in the radial wavenumber domain. Typically, computations use discrete wave number (DWN) formalism and Fourier analysis allows for solution in space and time domain. Experimentally, these elastic Greeńs functions might be retrieved from ambient vibrations correlations when assuming a diffuse field. In fact, the field could not be totally diffuse and only parts of the Green's functions, associated to surface or body waves, are retrieved. In this communication, we explore the computation of Green functions for a layered media on top of a half-space using a set of equipartitioned elastic plane waves. Our formalism includes body and surface waves (Rayleigh and Love waves). These latter waves correspond to the classical representations in terms of normal modes in the asymptotic case of large separation distance between source and receiver. This approach allows computing Green's functions faster than DWN and separating the surface and body wave contributions in order to better represent Green's function experimentally retrieved.

  20. American Indian Population Statistics.

    ERIC Educational Resources Information Center

    Thomason, Timothy C., Ed.

    This report summarizes American Indian and Alaska Native (AI/AN) population statistics from the 1990 Census. In 1990 there were about 2 million persons who identified themselves as American Indians in the United States, a 38 percent increase over the 1980 census. More than half of the Indian population lived in six states, with Oklahoma having the…

  1. Arab gene geography: From population diversities to personalized medical genomics

    PubMed Central

    Tadmouri, Ghazi O.; Sastry, Konduru S.; Chouchane, Lotfi

    2014-01-01

    Genetic disorders are not equally distributed over the geography of the Arab region. While a number of disorders have a wide geographical presence encompassing 10 or more Arab countries, almost half of these disorders occur in a single Arab country or population. Nearly, one-third of the genetic disorders in Arabs result from congenital malformations and chromosomal abnormalities, which are also responsible for a significant proportion of neonatal and perinatal deaths in Arab populations. Strikingly, about two-thirds of these diseases in Arab patients follow an autosomal recessive mode of inheritance. High fertility rates together with increased consanguineous marriages, generally noticed in Arab populations, tend to increase the rates of genetic and congenital abnormalities. Many of the nearly 500 genes studied in Arab people revealed striking spectra of heterogeneity with many novel and rare mutations causing large arrays of clinical outcomes. In this review we provided an overview of Arab gene geography, and various genetic abnormalities in Arab populations, including disorders of blood, metabolic, circulatory and neoplasm, and also discussed their associated molecules or genes responsible for the cause of these disorders. Although studying Arab-specific genetic disorders resulted in a high value knowledge base, approximately 35% of genetic diseases in Arabs do not have a defined molecular etiology. This is a clear indication that comprehensive research is required in this area to understand the molecular pathologies causing diseases in Arab populations. PMID:25780794

  2. Geometric Effects on the Amplification of First Mode Instability Waves

    NASA Technical Reports Server (NTRS)

    Kirk, Lindsay C.; Candler, Graham V.

    2013-01-01

    The effects of geometric changes on the amplification of first mode instability waves in an external supersonic boundary layer were investigated using numerical techniques. Boundary layer stability was analyzed at Mach 6 conditions similar to freestream conditions obtained in quiet ground test facilities so that results obtained in this study may be applied to future test article design to measure first mode instability waves. The DAKOTA optimization software package was used to optimize an axisymmetric geometry to maximize the amplification of the waves at first mode frequencies as computed by the 2D STABL hypersonic boundary layer stability analysis tool. First, geometric parameters such as nose radius, cone half angle, vehicle length, and surface curvature were examined separately to determine the individual effects on the first mode amplification. Finally, all geometric parameters were allowed to vary to produce a shape optimized to maximize the amplification of first mode instability waves while minimizing the amplification of second mode instability waves. Since first mode waves are known to be most unstable in the form of oblique wave, the geometries were optimized using a broad range of wave frequencies as well as a wide range of oblique wave angles to determine the geometry that most amplifies the first mode waves. Since first mode waves are seen most often in flows with low Mach numbers at the edge of the boundary layer, the edge Mach number for each geometry was recorded to determine any relationship between edge Mach number and the stability of first mode waves. Results indicate that an axisymmetric cone with a sharp nose and a slight flare at the aft end under the Mach 6 freestream conditions used here will lower the Mach number at the edge of the boundary layer to less than 4, and the corresponding stability analysis showed maximum first mode N factors of 3.

  3. The Population of Optically Faint GEO Debris

    NASA Technical Reports Server (NTRS)

    Seitzer, Patrick; Barker, Ed; Buckalew, Brent; Burkhardt, Andrew; Cowardin, Heather; Frith, James; Gomez, Juan; Kaleida, Catherine; Lederer, Susan M.; Lee, Chris H.

    2016-01-01

    The 6.5-m Magellan telescope 'Walter Baade' at the Las Campanas Observatory in Chile has been used for spot surveys of the GEO orbital regime to study the population of optically faint GEO debris. The goal is to estimate the size of the population of GEO debris at sizes much smaller than can be studied with 1-meter class telescopes. Despite the small size of the field of view of the Magellan instrument (diameter 0.5-degree), a significant population of objects fainter than R = 19th magnitude have been found with angular rates consistent with circular orbits at GEO. We compare the size of this population with the numbers of GEO objects found at brighter magnitudes by smaller telescopes. The observed detections have a wide range in characteristics starting with those appearing as short uniform streaks. But there are a substantial number of detections with variations in brightness, flashers, during the 5-second exposure. The duration of each of these flashes can be extremely brief: sometimes less than half a second. This is characteristic of a rapidly tumbling object with a quite variable projected size times albedo. If the albedo is of the order of 0.2, then the largest projected size of these objects is around 10-cm. The data in this paper was collected over the last several years using Magellan's IMACS camera in f/2 mode. The analysis shows the brightness bins for the observed GEO population as well as the periodicity of the flashers. All objects presented are correlated with the catalog: the focus of the paper will be on the uncorrelated, optically faint, objects. The goal of this project is to better characterize the faint debris population in GEO that access to a 6.5-m optical telescope in a superb site can provide.

  4. A method for selective excitation of Ince-Gaussian modes in an end-pumped solid-state laser

    NASA Astrophysics Data System (ADS)

    Lei, J.; Hu, A.; Wang, Y.; Chen, P.

    2014-12-01

    A method for selective excitation of Ince-Gaussian modes is presented. The method is based on the spatial distributions of Ince-Gaussian modes as well as the transverse mode selection theory. Significant diffraction loss is introduced in a resonator by using opaque lines at zero-intensity positions, and this loss allows to excite a specific mode; we call this method "loss control." We study the method by means of numerical simulation of a half-symmetric laser resonator. The simulated field is represented by angular spectrum of the plane waves representation, and its changes are calculated by the two-dimensional fast Fourier transform algorithm when it passes through the optical elements and propagates back and forth in the resonator. The output lasing modes of our method have an overlap of over 90 % with the target Ince-Gaussian modes. The method will be beneficial to the further study of properties and potential applications of Ince-Gaussian modes.

  5. The novel benzopyran class of selective cyclooxygenase-2 inhibitors. Part 2: The second clinical candidate having a shorter and favorable human half-life

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

    Wang, Jane L.; Limburg, David; Graneto, Matthew J.

    2012-05-29

    In this Letter, we provide the structure-activity relationships, optimization of design, testing criteria, and human half-life data for a series of selective COX-2 inhibitors. During the course of our structure-based drug design efforts, we discovered two distinct binding modes within the COX-2 active site for differently substituted members of this class. The challenge of a undesirably long human half-life for the first clinical candidate 1t{sub 1/2} = 360 h was addressed by multiple strategies, leading to the discovery of 29b-(S) (SC-75416) with t{sub 1/2} = 34 h.

  6. Mode-specific vibrational excitation and energy redistribution after ultrafast intramolecular electron transfer

    NASA Astrophysics Data System (ADS)

    Hogiu, S.; Werncke, W.; Pfeiffer, M.; Dreyer, J.; Elsaesser, T.

    2000-07-01

    Vibrational relaxation in the electronic ground state initiated by intramolecular back-electron transfer (b-ET) of betaine-30 (B-30) is studied by picosecond time-resolved anti-Stokes Raman spectroscopy. Measurements were carried out with B-30 dissolved in slowly as well as in rapidly relaxing solvents. We observed a risetime of the Raman band with the highest frequency near 1600 cm-1 which is close to the b-ET time τb-ET of B-30. For B-30 dissolved in propylene carbonate (τb-ET˜1 ps), the population of this mode exhibits a rise time of 1 ps whereas vibrational populations between 400 and 1400 cm-1 increase substantially slower. In contrast, in glycerol triacetin (τb-ET˜3.5 ps) and in ethanol (τb-ET˜6 ps) rise times of all modes are close to the respective b-ET times. Within the first few picoseconds, direct vibrational excitation through b-ET is favored for modes with the highest frequencies and high Franck-Condon factors. Later on, indirect channels of population due to vibrational energy redistribution (IVR) become effective. Thermal equilibrium populations of the Raman active modes are established within 10 to 15 ps after optical excitation.

  7. Reflection and transmission of elastic waves through a couple-stress elastic slab sandwiched between two half-spaces

    NASA Astrophysics Data System (ADS)

    Wang, Changda; Chen, Xuejun; Wei, Peijun; Li, Yueqiu

    2017-12-01

    The reflection and transmission of elastic waves through a couple-stress elastic slab that is sandwiched between two couple-stress elastic half-spaces are studied in this paper. Because of the couple-stress effects, there are three types of elastic waves in the couple-stress elastic solid, two of which are dispersive. The interface conditions between two couple-stress solids involve the surface couple and rotation apart from the surface traction and displacement. The nontraditional interface conditions between the slab and two solid half-spaces are used to obtain the linear algebraic equation sets from which the amplitude ratios of reflection and transmission waves to the incident wave can be determined. Then, the energy fluxes carried by the various reflection and transmission waves are calculated numerically and the normal energy flux conservation is used to validate the numerical results. The special case, couple-stress elastic slab sandwiched by the classical elastic half-spaces, is also studied and compared with the situation that the classical elastic slab sandwiched by the classical elastic half-spaces. Incident longitudinal wave (P wave) and incident transverse wave (SV wave) are both considered. The influences of the couple-stress are mainly discussed based on the numerical results. It is found that the couple-stress mainly influences the transverse modes of elastic waves.

  8. Our Population Predicament: A New Look.

    ERIC Educational Resources Information Center

    van der Tak, Jean, Ed.; And Others

    1979-01-01

    This Bulletin updates the story of world population presented in 1971, "Man's Population Predicament." Estimated at half a billion in 1650, world population reached 2 billion in 1930, 4 billion in 1975, and is projected to be about 6 billion in 2000. Most of today's rapid growth is occurring among people living in less developed…

  9. Association Between Obstetric Mode of Delivery and Autism Spectrum Disorder: A Population-Based Sibling Design Study.

    PubMed

    Curran, Eileen A; Dalman, Christina; Kearney, Patricia M; Kenny, Louise C; Cryan, John F; Dinan, Timothy G; Khashan, Ali S

    2015-09-01

    Because the rates of cesarean section (CS) are increasing worldwide, it is becoming increasingly important to understand the long-term effects that mode of delivery may have on child development. To investigate the association between obstetric mode of delivery and autism spectrum disorder (ASD). Perinatal factors and ASD diagnoses based on the International Classification of Diseases, Ninth Revision (ICD-9),and the International Statistical Classification of Diseases, 10th Revision (ICD-10),were identified from the Swedish Medical Birth Register and the Swedish National Patient Register. We conducted stratified Cox proportional hazards regression analysis to examine the effect of mode of delivery on ASD. We then used conditional logistic regression to perform a sibling design study, which consisted of sibling pairs discordant on ASD status. Analyses were adjusted for year of birth (ie, partially adjusted) and then fully adjusted for various perinatal and sociodemographic factors. The population-based cohort study consisted of all singleton live births in Sweden from January 1, 1982, through December 31, 2010. Children were followed up until first diagnosis of ASD, death, migration, or December 31, 2011 (end of study period), whichever came first. The full cohort consisted of 2,697,315 children and 28,290 cases of ASD. Sibling control analysis consisted of 13,411 sibling pairs. Obstetric mode of delivery defined as unassisted vaginal delivery (VD), assisted VD, elective CS, and emergency CS (defined by before or after onset of labor). The ASD status as defined using codes from the ICD-9 (code 299) and ICD-10 (code F84). In adjusted Cox proportional hazards regression analysis, elective CS (hazard ratio, 1.21; 95% CI, 1.15-1.27) and emergency CS (hazard ratio, 1.15; 95% CI, 1.10-1.20) were associated with ASD when compared with unassisted VD. In the sibling control analysis, elective CS was not associated with ASD in partially (odds ratio [OR], 0.97; 95% CI, 0

  10. California State Waters Map Series: offshore of Half Moon Bay, California

    USGS Publications Warehouse

    Cochrane, Guy R.; Dartnell, Peter; Greene, H. Gary; Johnson, Samuel Y.; Golden, Nadine E.; Hartwell, Stephen R.; Dieter, Bryan E.; Manson, Michael W.; Sliter, Ray W.; Ross, Stephanie L.; Watt, Janet T.; Endris, Charles A.; Kvitek, Rikk G.; Phillips, Eleyne L.; Erdey, Mercedes D.; Chin, John L.; Bretz, Carrie K.

    2014-01-01

    In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpretation, and visualization of swath sonar data, acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the surficial seafloor geology and shallow (to about 100 m) subsurface geology. The Offshore of Half Moon Bay map area is located in northern California, on the Pacific coast of the San Francisco Peninsula about 40 kilometers south of the Golden Gate. The city of Half Moon Bay, which is situated on the east side of the Half Moon Bay embayment, is the nearest significant onshore cultural center in the map area, with a population of about 11,000. The Pillar Point Harbor at the north edge of Half Moon Bay offers a protected landing for boats and provides other marine infrastructure. The map area lies offshore of the Santa Cruz Mountains, part of the northwest-trending Coast Ranges that run roughly parallel to the San Andreas Fault Zone. The Santa Cruz Mountains lie between the San Andreas Fault Zone and the San Gregorio Fault system. The flat coastal area, which is the most recent of numerous marine terraces, was formed by wave erosion about 105 thousand years ago. The higher elevation of this same terrace west of the Half Moon Bay Airport is caused by uplift on the Seal Cove Fault, a splay of the San Gregorio Fault Zone. Although originally incised into the rising terrain horizontally, the ancient terrace surface has been gently folded into a northwest-plunging syncline by

  11. Chiral Majorana fermion modes in a quantum anomalous Hall insulator–superconductor structure

    DOE PAGES

    He, Qing Lin; Pan, Lei; Stern, Alexander L.; ...

    2017-07-21

    Majorana fermion is a hypothetical particle that is its own antiparticle. We report transport measurements that suggest the existence of one-dimensional chiral Majorana fermion modes in the hybrid system of a quantum anomalous Hall insulator thin film coupled with a superconductor. As the external magnetic field is swept, half-integer quantized conductance plateaus are observed at the locations of magnetization reversals, giving a distinct signature of the Majorana fermion modes. This transport signature is reproducible over many magnetic field sweeps and appears at different temperatures. This finding may open up an avenue to control Majorana fermions for implementing robust topological quantummore » computing.« less

  12. 7 CFR 51.2296 - Three-fourths half kernel.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Three-fourths half kernel. 51.2296 Section 51.2296 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards...-fourths half kernel. Three-fourths half kernel means a portion of a half of a kernel which has more than...

  13. Ducted whistler-mode signals received at two widely spaced locations

    NASA Astrophysics Data System (ADS)

    Clilverd, M. A.; Thomson, N. R.; Smith, A. J.

    1996-06-01

    Whistler-mode signals from a single VLF transmitter that have propagated in the same duct, have been observed simultaneously at Faraday, Antarctica (65°S, 64°W) and Dunedin, New Zealand (46°S, 171°E). The signals received have group-delay times that differ in the order of 10 ms, which can be explained by the differences in southern-hemisphere sub-ionospheric propagation time from duct exit region to receiver for the two sites. This difference has been used to determine the location of the duct exit region, with confirmation provided by arrival-bearing information from both sites. The whistler-mode signals typically occur one or two days after geomagnetic activity, with Kpgeq5. The sub-ionospheric-propagation model, LWPC, is used to estimate the whistler-mode power radiated from the duct exit region. These results are then combined with estimated loss values for ionospheric and ducted transmission to investigate the role of wave-particle amplification or absorption. On at least half of the events studied, plasmaspheric amplification of the signals appears to be needed to explain the observed whistler-mode signal strengths.

  14. Sexual violence and mode of delivery: a population-based cohort study.

    PubMed

    Henriksen, L; Schei, B; Vangen, S; Lukasse, M

    2014-09-01

    This study aimed to explore the association between sexual violence and mode of delivery. National cohort study. Women presenting for routine ultrasound examinations were recruited to the Norwegian Mother and Child Cohort Study between 1999 and 2008. A total of 74,059 pregnant women. Sexual violence was self-reported during pregnancy using postal questionnaires. Mode of delivery, other maternal birth outcomes and covariates were retrieved from the Medical Birth Registry of Norway. Risk estimations were performed using multivariable logistic regression analysis. Mode of delivery and selected maternal birth outcomes. Of 74,059 women, 18.4% reported a history of sexual violence. A total of 10% had an operative vaginal birth, 4.9% had elective caesarean section and 8.6% had an emergency caesarean section. Severe sexual violence (rape) was associated with elective caesarean section, adjusted odds ratio (AOR) 1.56 (95% CI 1.18-2.05) for nulliparous women and 1.37 (1.06-1.76) for multiparous women. Those exposed to moderate sexual violence had a higher risk of emergency caesarean section, AOR 1.31 (1.07-1.60) and 1.41 (1.08-1.84) for nulliparous and multiparous women, respectively. No association was found between sexual violence and operative vaginal birth, except for a lower risk among multiparous women reporting mild sexual violence, AOR 0.73 (0.60-0.89). Analysis of other maternal outcomes showed a reduced risk of episiotomy for women reporting rape and a higher frequency of induced labour. Women with a history of rape had higher odds of elective caesarean section and induction and significantly fewer episiotomies. © 2014 Royal College of Obstetricians and Gynaecologists.

  15. Are stepfathers' education levels associated with the intelligence of their stepsons? A register-based study of Norwegian half-brothers.

    PubMed

    Eriksen, Willy; Sundet, Jon M; Tambs, Kristian

    2013-05-01

    We examined the relationship between the parents' education levels and the adult intelligence of their children in a population-based, nationwide sample of Norwegian half-brothers with different fathers (2,016 pairs of half-brothers). In a family where the mother has two children with different men, the firstborn child usually lives with the younger child's father during a period of their childhood. This makes it possible to study the non-genetic effects of paternal education on children's development. Results showed that the education level of the younger half-brother's father was positively associated with the intelligence score of the older half-brother. The education level of the older half-brother's father was not associated with the intelligence score of the younger half-brother. Firstborn men whose half-brothers' fathers had high levels of education had intelligence scores that were 33% (95% confidence interval: 18-47%) of a standard deviation higher than those of firstborn men whose half-brothers' fathers had low levels of education, after adjustment for the biological fathers' education levels, mothers' education levels, and other background factors. These findings are compatible with the hypothesis that a child's family environment exerts an effect on the cognitive abilities of the child that lasts into adulthood. © 2012 The British Psychological Society.

  16. Factorial Structure and Preliminary Validation of the Schema Mode Inventory for Eating Disorders (SMI-ED)

    PubMed Central

    Simpson, Susan G.; Pietrabissa, Giada; Rossi, Alessandro; Seychell, Tahnee; Manzoni, Gian Mauro; Munro, Calum; Nesci, Julian B.; Castelnuovo, Gianluca

    2018-01-01

    Objective: The aim of this study was to examine the psychometric properties and factorial structure of the Schema Mode Inventory for Eating Disorders (SMI-ED) in a disordered eating population. Method: 573 participants with disordered eating patterns as measured by the Eating Disorder Examination Questionnaire (EDE-Q) completed the 190-item adapted version of the Schema Mode Inventory (SMI). The new SMI-ED was developed by clinicians/researchers specializing in the treatment of eating disorders, through combining items from the original SMI with a set of additional questions specifically representative of the eating disorder population. Psychometric testing included Confirmatory Factor Analysis (CFA) and internal consistency (Cronbach's α). Multivariate Analyses of Covariance (MANCOVA) was also run to test statistical differences between the EDE-Q subscales on the SMI-ED modes, while controlling for possible confounding variables. Results: Factorial analysis confirmed an acceptable 16-related-factors solution for the SMI-ED, thus providing preliminary evidence for the adequate validity of the new measure based on internal structure. Concurrent validity was also established through moderate to high correlations on the modes most relevant to eating disorders with EDE-Q subscales. This study represents the first step in creating a psychometrically sound instrument for measuring schema modes in eating disorders, and provides greater insight into the relevant schema modes within this population. Conclusion: This research represents an important preliminary step toward understanding and labeling the schema mode model for this clinical group. Findings from the psychometric evaluation of SMI-ED suggest that this is a useful tool which may further assist in the measurement and conceptualization of schema modes in this population. PMID:29740379

  17. Factorial Structure and Preliminary Validation of the Schema Mode Inventory for Eating Disorders (SMI-ED).

    PubMed

    Simpson, Susan G; Pietrabissa, Giada; Rossi, Alessandro; Seychell, Tahnee; Manzoni, Gian Mauro; Munro, Calum; Nesci, Julian B; Castelnuovo, Gianluca

    2018-01-01

    Objective: The aim of this study was to examine the psychometric properties and factorial structure of the Schema Mode Inventory for Eating Disorders (SMI-ED) in a disordered eating population. Method: 573 participants with disordered eating patterns as measured by the Eating Disorder Examination Questionnaire (EDE-Q) completed the 190-item adapted version of the Schema Mode Inventory (SMI). The new SMI-ED was developed by clinicians/researchers specializing in the treatment of eating disorders, through combining items from the original SMI with a set of additional questions specifically representative of the eating disorder population. Psychometric testing included Confirmatory Factor Analysis (CFA) and internal consistency (Cronbach's α). Multivariate Analyses of Covariance (MANCOVA) was also run to test statistical differences between the EDE-Q subscales on the SMI-ED modes, while controlling for possible confounding variables. Results: Factorial analysis confirmed an acceptable 16-related-factors solution for the SMI-ED, thus providing preliminary evidence for the adequate validity of the new measure based on internal structure. Concurrent validity was also established through moderate to high correlations on the modes most relevant to eating disorders with EDE-Q subscales. This study represents the first step in creating a psychometrically sound instrument for measuring schema modes in eating disorders, and provides greater insight into the relevant schema modes within this population. Conclusion: This research represents an important preliminary step toward understanding and labeling the schema mode model for this clinical group. Findings from the psychometric evaluation of SMI-ED suggest that this is a useful tool which may further assist in the measurement and conceptualization of schema modes in this population.

  18. Effect of sonic application mode on the resin-dentin bond strength and dentin permeability of self-etching systems.

    PubMed

    Mena-Serrano, Alexandra; Costa, Thays Regina Ferreira da; Patzlaff, Rafael Tiago; Loguercio, Alessandro Dourado; Reis, Alessandra

    2014-10-01

    To compare manual and sonic adhesive application modes in terms of the permeability and microtensile bond strength of a self-etching adhesive applied in the one-step or two-step protocol. Self-etching All Bond SE (Bisco) was applied as a one- or a two-step adhesive under manual or sonic vibration modes on flat occlusal dentin surfaces of 64 human molars. Half of the teeth were used to measure the hydraulic conductance of dentin at 200 cm H₂O hydrostatic pressure for 5 min immediately after the adhesive application. In the other half, composite buildups (Opallis) were constructed incrementally to create resin-dentin sticks with a cross-sectional area of 0.8 mm² to be tested in tension (0.5 mm/min) immediately after restoration placement. Data were analyzed using a two-way ANOVA and Tukey's test (α = 0.05). The fluid conductance of dentin was significantly reduced by the sonic vibration mode for both adhesives, but no effect on the bond strength values was observed for either adhesive. The sonic application mode at an oscillating frequency of 170 Hz can reduce the fluid conductance of the one- and two-step All Bond SE adhesive when applied on dentin.

  19. Predictions on the modes of decay of odd Z superheavy isotopes within the range 105 ≤ Z ≤ 135

    NASA Astrophysics Data System (ADS)

    Santhosh, K. P.; Nithya, C.

    2018-05-01

    The decay modes of 1051 odd Z superheavy nuclei within the range 105 ≤ Z ≤ 135, and their daughter nuclei are studied by comparing the alpha decay half-lives with the spontaneous fission half-lives. The alpha decay half-lives are calculated using the Coulomb and proximity potential model for deformed nuclei (CPPMDN) proposed by Santhosh et al. (2011) and the spontaneous fission half-lives are obtained with the shell-effect dependent formula of Santhosh et al. (Santhosh and Nithya, 2016). For a theoretical comparison, the alpha decay half-lives are also computed with the Coulomb and proximity potential model (CPPM), Viola-Seaborg-Sobiczewski semi-empirical relation (VSS), Universal curve of Poenaru et al. (UNIV), the analytical formula of Royer, and the Universal decay law of Qi et al. (UDL). The predicted decay modes and half-lives were compared with the available experimental results. The proton and neutron separation energies are calculated to identify those nuclei, which decay through proton and neutron emission. From the entire study of odd Z superheavy elements, it is seen that among 1051 nuclei, 233 nuclei exhibit proton emission and 18 nuclei exhibit neutron emission. 56 nuclei are stable against alpha decay with negative Q value for the decay. 92 nuclei show alpha decay followed by spontaneous fission and 9 nuclei show alpha decay followed by proton emission. 39 nuclei decay through full alpha chain and 595 nuclei decay through spontaneous fission. We hope that the study will be very useful for the future experimental investigations in this field.

  20. Detectors for the Atacama B-mode Search experiment

    NASA Astrophysics Data System (ADS)

    Appel, John William

    Inflation is the leading theory for explaining the initial conditions that brought about our homogeneous and isotropic Universe. It predicts the presence of gravitational waves in the early Universe, which implant a characteristic B-mode polarization pattern on the Cosmic Microwave Background (CMB). The Atacama B-mode Search (ABS) experiment is a polarimeter observing from Cerro Toco (located in the Atacama desert of Chile at an altitude of 5190 m), searching for the yet undetected B-mode signal. ABS carries 480 superconducting Transition Edge Sensor (TES) Bolometers that couple 150 GHz radiation via planar Ortho-Mode Transducers (OMTs) mounted at the output of corrugated feedhorns. The feedhorn beam is projected onto the sky through crossed Dragonian reflectors, a set of reflective and absorptive filters, and a rotating Half Wave Plate (HWP) that modulates any polarized sky signal at 10.2 Hz. The bolometers are cooled to 300 mK by a He3-He4 adsorption fridge system backed by pulse tubes. The reflectors are located within the 4 K cavity of the cryostat, while the HWP is mounted on frictionless air bearings above the cryostat window. This thesis discusses the development and construction of the ABS detector focal plane, and presents results of its performance in the field through August 2012. The ABS detector array sensitivity of 31 μKs 1/2, together with the experiment's unique set of systematic controls, and expected multi-year integration time, could detect a B-mode signal with tensor to scalar ratio r ˜ 0.1.

  1. The association between unequal parental treatment and the sibling relationship in Finland: The difference between full and half-siblings.

    PubMed

    Danielsbacka, Mirkka; Tanskanen, Antti O

    2015-06-24

    Studies have shown that unequal parental treatment is associated with relationship quality between siblings. However, it is unclear how it affects the relationship between full and half-siblings. Using data from the Generational Transmissions in Finland project (n = 1,537 younger adults), we study whether those who have half-siblings perceive more unequal parental treatment than those who have full siblings only. In addition, we study how unequal parental treatment is associated with sibling relationship between full, maternal, and paternal half-siblings. First, we found that individuals who have maternal and/or paternal half-siblings are more likely to have encountered unequal maternal treatment than individuals who have full siblings only. Second, we found that unequal parental treatment impairs full as well as maternal and paternal half-sibling relations in adulthood. Third, unequal parental treatment mediates the effect of genetic relatedness on sibling relations in the case of maternal half-siblings, but not in the case of paternal half-siblings. After controlling for unequal parental treatment, the quality of maternal half-sibling relationships did not differ from that of full siblings, whereas the quality of paternal half-sibling relationships still did. Fourth, the qualitative comments (n = 206) from the same population reveal that unequal parental treatment presents itself several ways, such as differential financial, emotional, or practical support.

  2. Anisotropy in layered half-metallic Heusler alloy superlattices

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

    Azadani, Javad G.; Munira, Kamaram; Sivakumar, Chockalingam

    2016-01-28

    We show that when two Heusler alloys are layered in the [001], [110], or [111] directions for various thicknesses to form a superlattice, the Slater-Pauling rule may still be satisfied and the resulting superlattice is often half-metallic with gaps comparable to or larger than those of its constituents. In addition, uniaxial magnetocrystalline anisotropy is induced because of the differences in the electronic structure of the two Heuslers in the superlattice. Various full-full, full-half, and half-half Heusler superlattices are studied, and potential half-metallic superlattices with perpendicular magnetocrystalline anisotropy are identified.

  3. Verification of quantum entanglement of two-mode squeezed light source towards quantum radar and imaging

    NASA Astrophysics Data System (ADS)

    Masada, Genta

    2017-08-01

    Two-mode squeezed light is an effective resource for quantum entanglement and shows a non-classical correlation between each optical mode. We are developing a two-mode squeezed light source to explore the possibility of quantum radar based on the quantum illumination theory. It is expected that the error probability for discrimination of target presence or absence is improved even in a lossy and noisy environment. We are also expecting to apply two-mode squeezed light source to quantum imaging. In this work we generated two-mode squeezed light and verify its quantum entanglement property towards quantum radar and imaging. Firstly we generated two independent single-mode squeezed light beams utilizing two sub-threshold optical parametric oscillators which include periodically-polled potassium titanyl phosphate crystals for the second order nonlinear interaction. Two single-mode squeezed light beams are combined using a half mirror with the relative optical phase of 90° between each optical field. Then entangled two-mode squeezed light beams can be generated. We observes correlation variances between quadrature phase amplitudes in entangled two-mode fields by balanced homodyne measurement. Finally we verified quantum entanglement property of two-mode squeezed light source based on Duan's and Simon's inseparability criterion.

  4. The detectability half-life in arthropod predator-prey research: what it is, why we need it, how to measure it, and how to use it.

    PubMed

    Greenstone, Matthew H; Payton, Mark E; Weber, Donald C; Simmons, Alvin M

    2014-08-01

    Molecular gut-content analysis enables detection of arthropod predation with minimal disruption of ecosystem processes. Most assays produce only qualitative results, with each predator testing either positive or negative for target prey remains. Nevertheless, they have yielded important insights into community processes. For example, they have confirmed the long-hypothesized role of generalist predators in retarding early-season build-up of pest populations prior to the arrival of more specialized predators and parasitoids and documented the ubiquity of secondary and intraguild predation. However, raw qualitative gut-content data cannot be used to assess the relative impact of different predator taxa on prey population dynamics: they must first be weighted by the relative detectability periods for molecular prey remains for each predator-prey combination. If this is not carried out, interpretations of predator impact will be biased towards those with the longest detectabilities. We review the challenges in determining detectability half-lives, including unstated assumptions that have often been ignored in the performance of feeding trials. We also show how detectability half-lives can be used to properly weight assay data to rank predators by their importance in prey population suppression, and how sets of half-lives can be used to test hypotheses concerning predator ecology and physiology. We use data from 32 publications, comprising 97 half-lives, to generate and test hypotheses on taxonomic differences in detectability half-lives and discuss the possible role of the detectability half-life in interpreting qPCR and next-generation sequencing data. © 2013 John Wiley & Sons Ltd.

  5. Theory of the mode stabilization mechanism in concave-micromirror-capped vertical-cavity surface-emitting lasers

    NASA Astrophysics Data System (ADS)

    Park, Si-Hyun; Park, Yeonsang; Jeon, Heonsu

    2003-08-01

    We have investigated theoretically the transverse mode stabilization mechanism in oxide-confined concave-micromirror-capped vertical-cavity surface-emitting lasers (CMC-VCSELs) as reported by Park et al. [Appl. Phys. Lett. 80, 183 (2002)]. From detailed numerical calculations on a model CMC-VCSEL structure, we found that mode discrimination factors appear to be periodic in the micromirror layer thickness with a periodicity of λ/2. We also found that there are two possible concave micromirror structures for the fundamental transverse mode laser operation. These structures can be grouped according to the thickness of the concave micromirror layer: whether it is an integer or a half-integer multiple of λ/2. The optimal micromirror curvature radius differs accordingly for each case. In an optimally designed CMC-VCSEL model structure, the fundamental transverse mode can be favored as much as 4, 8, and 13 times more strongly than the first, second, and third excited modes, respectively.

  6. Kinematic parameters of internal waves of the second mode in the South China Sea

    NASA Astrophysics Data System (ADS)

    Kurkina, Oxana; Talipova, Tatyana; Soomere, Tarmo; Giniyatullin, Ayrat; Kurkin, Andrey

    2017-10-01

    Spatial distributions of the main properties of the mode function and kinematic and non-linear parameters of internal waves of the second mode are derived for the South China Sea for typical summer conditions in July. The calculations are based on the Generalized Digital Environmental Model (GDEM) climatology of hydrological variables, from which the local stratification is evaluated. The focus is on the phase speed of long internal waves and the coefficients at the dispersive, quadratic and cubic terms of the weakly non-linear Gardner model. Spatial distributions of these parameters, except for the coefficient at the cubic term, are qualitatively similar for waves of both modes. The dispersive term of Gardner's equation and phase speed for internal waves of the second mode are about a quarter and half, respectively, of those for waves of the first mode. Similarly to the waves of the first mode, the coefficients at the quadratic and cubic terms of Gardner's equation are practically independent of water depth. In contrast to the waves of the first mode, for waves of the second mode the quadratic term is mostly negative. The results can serve as a basis for expressing estimates of the expected parameters of internal waves for the South China Sea.

  7. Divertor heat flux simulations in ELMy H-mode discharges of EAST

    NASA Astrophysics Data System (ADS)

    Xia, T. Y.; Xu, X. Q.; Wu, Y. B.; Huang, Y. Q.; Wang, L.; Zheng, Z.; Liu, J. B.; Zang, Q.; Li, Y. Y.; Zhao, D.; EAST Team

    2017-11-01

    This paper presents heat flux simulations for the ELMy H-mode on the Experimental Advanced Superconducting Tokamak (EAST) using a six-field two-fluid model in BOUT++. Three EAST ELMy H-mode discharges with different plasma currents I p and geometries are studied. The trend of the scrape-off layer width λq with I p is reproduced by the simulation. The simulated width is only half of that derived from the EAST scaling law, but agrees well with the international multi-machine scaling law. Note that there is no radio-frequency (RF) heating scheme in the simulations, and RF heating can change the boundary topology and increase the flux expansion. Anomalous electron transport is found to contribute to the divertor heat fluxes. A coherent mode is found in the edge region in simulations. The frequency and poloidal wave number kθ are in the range of the edge coherent mode in EAST. The magnetic fluctuations of the mode are smaller than the electric field fluctuations. Statistical analysis of the type of turbulence shows that the turbulence transport type (blobby or turbulent) does not influence the heat flux width scaling. The two-point model differs from the simulation results but the drift-based model shows good agreement with simulations.

  8. Half-marathoners are younger and slower than marathoners.

    PubMed

    Knechtle, Beat; Nikolaidis, Pantelis T; Zingg, Matthias A; Rosemann, Thomas; Rüst, Christoph A

    2016-01-01

    Age and performance trends of elite and recreational marathoners are well investigated, but not for half-marathoners. We analysed age and performance trends in 508,108 age group runners (125,894 female and 328,430 male half-marathoners and 10,205 female and 43,489 male marathoners) competing between 1999 and 2014 in all flat half-marathons and marathons held in Switzerland using single linear regression analyses, mixed-effects regression analyses and analyses of variance. The number of women and men increased across years in both half-marathons and marathons. There were 12.3 times more female half-marathoners than female marathoners and 7.5 times more male half-marathoners than male marathoners. For both half-marathons and marathons, most of the female and male finishers were recorded in age group 40-44 years. In half-marathons, women (10.29 ± 3.03 km/h) were running 0.07 ± 0.06 km/h faster (p < 0.001) than men (10.22 ± 3.06 km/h). Also in marathon, women (14.77 ± 4.13 km/h) were running 0.28 ± 0.16 km/h faster (p < 0.001) than men (14.48 ± 4.07 km/h). In marathon, women (42.18 ± 10.63 years) were at the same age than men (42.06 ± 10.45 years) (p > 0.05). Also in half-marathon, women (41.40 ± 10.63 years) were at the same age than men (41.31 ± 10.30 years) (p > 0.05). However, women and men marathon runners were older than their counterpart half-marathon runners (p < 0.001). In summary, (1) more athletes competed in half-marathons than in marathons, (2) women were running faster than men, (3) half-marathoners were running slower than marathoners, and (4) half-marathoners were younger than marathoners.

  9. Inferring the Mode of Selection from the Transient Response to Demographic Perturbations

    NASA Astrophysics Data System (ADS)

    Balick, Daniel; Do, Ron; Reich, David; Sunyaev, Shamil

    2014-03-01

    Despite substantial recent progress in theoretical population genetics, most models work under the assumption of a constant population size. Deviations from fixed population sizes are ubiquitous in natural populations, many of which experience population bottlenecks and re-expansions. The non-equilibrium dynamics introduced by a large perturbation in population size are generally viewed as a confounding factor. In the present work, we take advantage of the transient response to a population bottleneck to infer features of the mode of selection and the distribution of selective effects. We develop an analytic framework and a corresponding statistical test that qualitatively differentiates between alleles under additive and those under recessive or more general epistatic selection. This statistic can be used to bound the joint distribution of selective effects and dominance effects in any diploid sexual organism. We apply this technique to human population genetic data, and severely restrict the space of allowed selective coefficients in humans. Additionally, one can test a set of functionally or medically relevant alleles for the primary mode of selection, or determine the local regional variation in dominance coefficients along the genome.

  10. Fabrication and electro-optic characteristics of polymer-stabilized V-mode FLCD and intrinsic H-V-mode FLCD: their application to AM LCDs

    NASA Astrophysics Data System (ADS)

    Kobayashi, Shunsuke; Furuta, Hirokazu; Murakami, Yuji; Xu, Jun; Mochizuki, Akihiro

    2003-04-01

    Defect free polymer-stabilized (PS-)V-mode FLCDs and intrinsic half (H-)V-mode FLCDs have been fabricated; they exhibit high contrast ratio over 700:1 and high reliability for a temperature cycling test by using specially developed polyimide alignment materials, RN-1411 series, from Nissan Chem. Ind., and also by adopting special alignment technique such as appropriate rubbing technique, photoalignment, and ion beam irradiation techniques and also particularly developed polymer-stabilization technique. These FLCDs are shown to be useful for implementing a field sequential type full color (FS-FC) LCDs due to their fast response with the response time of τ = 100μs ~ 500μs that is 10 to 100 times faster that those of LCDs using NLCs. We have developed several prototype models of FS-FC LCDs having VGA specifications that exhibit good performance for displaying fast moving video rate images with wide color gamut.

  11. Analysis of a Generally Oriented Crack in a Functionally Graded Strip Sandwiched Between Two Homogeneous Half Planes

    NASA Technical Reports Server (NTRS)

    Shbeeb, N.; Binienda, W. K.; Kreider, K.

    1999-01-01

    The driving forces for a generally oriented crack embedded in a Functionally Graded strip sandwiched between two half planes are analyzed using singular integral equations with Cauchy kernels, and integrated using Lobatto-Chebyshev collocation. Mixed-mode Stress Intensity Factors (SIF) and Strain Energy Release Rates (SERR) are calculated. The Stress Intensity Factors are compared for accuracy with previously published results. Parametric studies are conducted for various nonhomogeneity ratios, crack lengths. crack orientation and thickness of the strip. It is shown that the SERR is more complete and should be used for crack propagation analysis.

  12. Calculation of pressure half-time.

    PubMed

    Oyama, Mark A; Weidman, Jess A; Cole, Steven G

    2008-06-01

    Doppler echocardiography is useful in assessing the severity of obstructive cardiac lesions, such as mitral valve stenosis. The Doppler study can be used to calculate pressure half-time (PHT), which is defined as the time required for the pressure gradient across an obstruction to decrease to half of its maximal value. Thus, PHT increases as the severity of stenosis increases. In this report, we describe the methodology involved in measuring PHT in a dog with mitral valve stenosis before and after balloon valvuloplasty.

  13. Three-mode mode-division-multiplexing passive optical network over 12-km low mode-crosstalk FMF using all-fiber mode MUX/DEMUX

    NASA Astrophysics Data System (ADS)

    Ren, Fang; Li, Juhao; Wu, Zhongying; Hu, Tao; Yu, Jinyi; Mo, Qi; He, Yongqi; Chen, Zhangyuan; Li, Zhengbin

    2017-01-01

    We propose three-mode mode-division-multiplexing passive optical network (MDM-PON) based on low mode-crosstalk few-mode fiber (FMF) and all-fiber mode multiplexer/demultiplexer (MUX/DEMUX). The FMF with step-index profile is designed and fabricated for effectively three-independent-spatial-mode transmission and low mode-crosstalk for MDM-PON transmission. The all-fiber mode MUX/DEMUX are composed of cascaded mode selective couplers (MSCs), which simultaneously multiplex or demultiplex multiple modes. Based on the low mode-crosstalk of the FMF and all-fiber mode MUX/DEMUX, each optical network unit (ONU) communicates with the optical line terminal (OLT) independently utilizing a different optical linearly polarized (LP) spatial mode in MDM-PON system. We experimentally demonstrate MDM-PON transmission of three independent-spatial-modes over 12-km FMF with 10-Gb/s optical on-off keying (OOK) signal and direct detection.

  14. A study of air breathing rockets. 3: Supersonic mode combustors

    NASA Astrophysics Data System (ADS)

    Masuya, G.; Chinzel, N.; Kudo, K.; Murakami, A.; Komuro, T.; Ishii, S.

    An experimental study was made on supersonic mode combustors of an air breathing rocket engine. Supersonic streams of room-temperature air and hot fuel-rich rocket exhaust were coaxially mixed and burned in a concially diverging duct of 2 deg half-angle. The effect of air inlet Mach number and excess air ratio was investigated. Axial wall pressure distribution was measured to calculate one dimensional change of Mach number and stagnation temperature. Calculated results showed that supersonic combustion occurred in the duct. At the exit of the duct, gas sampling and Pitot pressure measurement was made, from which radial distributions of various properties were deduced. The distribution of mass fraction of elements from rocket exhaust showed poor mixing performance in the supersonic mode combustors compared with the previously investigated cylindrical subsonic mode combustors. Secondary combustion efficiency correlated well with the centerline mixing parameter, but not with Annushkin's non-dimensional combustor length. No major effect of air inlet Mach number or excess air ratio was seen within the range of conditions under which the experiment was conducted.

  15. Multi-operational tuneable Q-switched mode-locking Er fibre laser

    NASA Astrophysics Data System (ADS)

    Qamar, F. Z.

    2018-01-01

    A wavelength-spacing tuneable, Q-switched mode-locking (QML) erbium-doped fibre laser based on non-linear polarization rotation controlled by four waveplates and a cube polarizer is proposed. A mode-locked pulse train using two quarter-wave plates and a half-wave plate (HWP) is obtained first, and then an extra HWP is inserted into the cavity to produce different operation regimes. The evolutions of temporal and spectral dynamics with different orientation angles of the extra HWP are investigated. A fully modulated stable QML pulse train is observed experimentally. This is, to the author’s best knowledge, the first experimental work reporting QML operation without adding an extra saturable absorber inside the laser cavity. Multi-wavelength pulse laser operation, multi-pulse train continuous-wave mode-locking operation and pulse-splitting operations are also reported at certain HWP angles. The observed operational dynamics are interpreted as a mutual interaction of dispersion, non-linear effect and insertion loss. This work provides a new mechanism for fabricating cheap tuneable multi-wavelength lasers with QML pulses.

  16. Amerciamysis bahia Stochastic Matrix Population Model for Laboratory Populations

    EPA Science Inventory

    The population model described here is a stochastic, density-independent matrix model for integrating the effects of toxicants on survival and reproduction of the marine invertebrate, Americamysis bahia. The model was constructed using Microsoft® Excel 2003. The focus of the mode...

  17. Waveguide resonance mode response of stacked structures of metallic sub-wavelength slit arrays

    NASA Astrophysics Data System (ADS)

    Tokuda, Yasunori; Takano, Keisuke; Sakaguchi, Koichiro; Kato, Kosaku; Nakajima, Makoto; Akiyama, Koichi

    2018-05-01

    Detailed measurements of the optical properties of two-tier systems composed of metallic plates perforated with periodic sub-wavelength slit patterns were carried out using terahertz time-domain spectroscopy. We demonstrate that the transmission properties observed experimentally for various configurations can be reproduced successfully by simulations based on the finite-differential time-domain method. Fabry-Perot-like waveguide resonance mode behaviors specific to this quasi-dielectric system were then investigated. For structures with no lateral displacement between the slit-array plates, mode disappearance phenomena, which are caused by destructive interference between the odd-order mode and the blue- or red-shifted even-order modes, were observed experimentally. The uncommon behavior of the even-order modes was examined precisely to explain the slit-width dependence. For structures with half-pitched displacement between the plates, extraordinarily strong transmission was observed experimentally, even when the optical paths were shut off. This result was interpreted in terms of the propagation of surface plasmon polaritons through very thin and labyrinthine spacings that inevitably exist between the metallic plates. Furthermore, the optical mode disappearance phenomena are revealed to be characterized by anticrossing of the two mixing modes formed by even- and odd-order modes. These experimental observations that are supported theoretically are indispensable to the practical use of this type of artificial dielectric and are expected to encourage interest in optical mode behaviors that are not typically observed in conventional dielectric systems.

  18. G-band harmonic multiplying gyrotron traveling-wave amplifier with a mode-selective circuit

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

    Yeh, Y. S.; Chen, Chang-Hong; Wang, Z. W.

    Harmonic multiplying gyrotron traveling-wave amplifiers (gyro-TWAs) permit for magnetic field reduction and frequency multiplication. A high-order-mode harmonic multiplying gyro-TWA with large circuit dimensions and low ohmic loss can achieve a high average power. By amplifying a fundamental harmonic TE{sub 01} drive wave, the second harmonic component of the beam current initiates a TE{sub 02} wave to be amplified. Wall losses can suppress some competing modes because they act as an effective sink of the energy of the modes. However, such wall losses do not suppress all competing modes as the fields are contracted in the copper section in the gyro-TWA.more » An improved mode-selective circuit, using circular waveguides with the specified radii, can provide the rejection points within the frequency range to suppress the competing modes. The simulated results reveal that the mode-selective circuit can provide an attenuation of more than 10 dB to suppress the competing modes (TE{sub 21}, TE{sub 51}, TE{sub 22}, and TE{sub 03}). A G-band second harmonic multiplying gyro-TWA with the mode-selective circuit is predicted to yield a peak output power of 50 kW at 198.8 GHz, corresponding to a saturated gain of 55 dB at an interaction efficiency of 10%. The full width at half maximum bandwidth is 5 GHz.« less

  19. Two-mode PLC-based mode multi/demultiplexer for mode and wavelength division multiplexed transmission.

    PubMed

    Hanzawa, Nobutomo; Saitoh, Kuimasa; Sakamoto, Taiji; Matsui, Takashi; Tsujikawa, Kyozo; Koshiba, Masanori; Yamamoto, Fumihiko

    2013-11-04

    We proposed a PLC-based mode multi/demultiplexer (MUX/DEMUX) with an asymmetric parallel waveguide for mode division multiplexed (MDM) transmission. The mode MUX/DEMUX including a mode conversion function with an asymmetric parallel waveguide can be realized by matching the effective indices of the LP(01) and LP(11) modes of two waveguides. We report the design of a mode MUX/DEMUX that can support C-band WDM-MDM transmission. The fabricated mode MUX/DEMUX realized a low insertion loss of less than 1.3 dB and high a mode extinction ratio that exceeded 15 dB. We used the fabricated mode MUX/DEMUX to achieve a successful 2 mode x 4 wavelength x 10 Gbps transmission over a 9 km two-mode fiber with a penalty of less than 1 dB.

  20. Optical notch filter with tunable bandwidth based on guided-mode resonant polarization-sensitive spectral feature.

    PubMed

    Qian, Linyong; Zhang, Dawei; Dai, Bo; Wang, Qi; Huang, Yuanshen; Zhuang, Songlin

    2015-07-13

    A novel bandwidth-tunable notch filter is proposed based on the guided-mode resonance effect. The notch is created due to the superposition spectra response of two guided-mode resonant filters. The compact, bandwidth tuning capability is realized by taking advantage the effect of spectra-to-polarization sensitivity in one-dimensional classical guided-mode resonance filter, and using a liquid crystal polarization rotator for precise and simple polarization control. The operation principle and the design of the device are presented, and we demonstrate it experimentally. The central wavelength is fixed at 766.4 nm with a relatively symmetric profile. The full width at half maximum bandwidth could be tuned from 8.6 nm to 18.2 nm by controlling the applied voltage in electrically-driving polarization rotator.

  1. Half-lives of 221Fr, 217At, 213Bi, 213Po and 209Pb from the 225Ac decay series.

    PubMed

    Suliman, G; Pommé, S; Marouli, M; Van Ammel, R; Stroh, H; Jobbágy, V; Paepen, J; Dirican, A; Bruchertseifer, F; Apostolidis, C; Morgenstern, A

    2013-07-01

    The half-lives of (221)Fr, (217)At, (213)Bi, (213)Po, and (209)Pb were measured by means of an ion-implanted planar Si detector for alpha and beta particles emitted from weak (225)Ac sources or from recoil sources, which were placed in a quasi-2π counting geometry. Recoil sources were prepared by collecting atoms from an open (225)Ac source onto a glass substrate. The (221)Fr and (213)Bi half-lives were determined by following the alpha particle emission rate of recoil sources as a function of time. Similarly, the (209)Pb half-life was determined from the beta particle count rate. The shorter half-lives of (217)At and (213)Po were deduced from delayed coincidence measurements on weak (225)Ac sources using digital data acquisition in list mode. The resulting values: T1/2((221)Fr)=4.806 (6) min, T1/2((217)At)=32.8 (3)ms, T1/2((213)Bi)=45.62 (6)min, T1/2((213)Po)=3.708 (8) μs, and T1/2((209)Pb)=3.232 (5)h were in agreement only with the best literature data. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Hairy black hole stability in AdS, quantum mechanics on the half-line and holography

    NASA Astrophysics Data System (ADS)

    Anabalón, Andrés; Astefanesei, Dumitru; Oliva, Julio

    2015-10-01

    We consider the linear stability of 4-dimensional hairy black holes with mixed boundary conditions in Anti-de Sitter spacetime. We focus on the mass of scalar fields around the maximally supersymmetric vacuum of the gauged N=8 supergravity in four dimensions, m 2 = -2 l -2. It is shown that the Schrödinger operator on the half-line, governing the S 2, H 2 or {{R}}^2 invariant mode around the hairy black hole, allows for non-trivial self-adjoint extensions and each of them corresponds to a class of mixed boundary conditions in the gravitational theory. Discarding the self-adjoint extensions with a negative mode impose a restriction on these boundary conditions. The restriction is given in terms of an integral of the potential in the Schrödinger operator resembling the estimate of Simon for Schrödinger operators on the real line. In the context of AdS/CFT duality, our result has a natural interpretation in terms of the field theory dual effective potential.

  3. Estimating biodegradation half-lives for use in chemical screening.

    PubMed

    Aronson, Dallas; Boethling, Robert; Howard, Philip; Stiteler, William

    2006-06-01

    Biodegradation half-lives are needed for many applications in chemical screening, but these data are not available for most chemicals. To address this, in phase one of this work we correlated the much more abundant ready and inherent biodegradation test data with measured half-lives for water and soil. In phase two, we explored the utility of the BIOWIN models (in EPI Suite) and molecular fragments for predicting half-lives. BIOWIN model output was correlated directly with measured half-lives, and new models were developed by re-regressing the BIOWIN fragments against the half-lives. All of these approaches gave the best results when used for binary (fast/slow) classification of half-lives, with accuracy generally in the 70-80% range. In the last phase, we used the collected half-life data to examine the default half-lives assigned by EPI Suite and the PBT Profiler for use as input to their level III multimedia models. It is concluded that estimated half-lives should not be used for purposes other than binning or prioritizing chemicals unless accuracy improves significantly.

  4. Mind the Mode: Differences in Paper vs. Web-Based Survey Modes Among Women With Cancer.

    PubMed

    Hagan, Teresa L; Belcher, Sarah M; Donovan, Heidi S

    2017-09-01

    Researchers administering surveys seek to balance data quality, sources of error, and practical concerns when selecting an administration mode. Rarely are decisions about survey administration based on the background of study participants, although socio-demographic characteristics like age, education, and race may contribute to participants' (non)responses. In this study, we describe differences in paper- and web-based surveys administered in a national cancer survivor study of women with a history of cancer to compare the ability of each survey administrative mode to provide quality, generalizable data. We compared paper- and web-based survey data by socio-demographic characteristics of respondents, missing data rates, scores on primary outcome measure, and administrative costs and time using descriptive statistics, tests of mean group differences, and linear regression. Our findings indicate that more potentially vulnerable patients preferred paper questionnaires and that data quality, responses, and costs significantly varied by mode and participants' demographic information. We provide targeted suggestions for researchers conducting survey research to reduce survey error and increase generalizability of study results to the patient population of interest. Researchers must carefully weigh the pros and cons of survey administration modes to ensure a representative sample and high-quality data. Copyright © 2017 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

  5. Treatment, Time, and Achievement: Do Searching Modes of Study Facilitate Learning?

    ERIC Educational Resources Information Center

    Rice, Marion J.

    This report is a synthesis of five research studies comparing the facilitative effects on learning of searching and reception modes of study. The following five studies are discussed: (1) J.R. Dale, the effects on achievement of using the forced inferential response mode in an intermediate grade population-geography unit; (2) D.D. Dumbleton, the…

  6. Fundamental-mode MMF transmission enabled by mode conversion

    NASA Astrophysics Data System (ADS)

    Wu, Zhongying; Li, Juhao; Tian, Yu; Ge, Dawei; Zhu, Jinglong; Ren, Fang; Mo, Qi; Yu, Jinyi; Li, Zhengbin; Chen, Zhangyuan; He, Yongqi

    2018-03-01

    Modal dispersion in conventional multi-mode fiber (MMF) will cause serious signal degradation and an effective solution is to restrict the signal transmission in the fundamental mode of MMF. In this paper, unlike previous methods by filtering out higher-order modes, we propose to adopt low-modal-crosstalk mode converters to realize fundamental-mode MMF transmission. We design and fabricate all-fiber mode-selective couplers (MSC), which perform mode conversion between the fundamental mode in single-mode fiber (SMF) and fundamental mode in MMF. The proposed scheme is experimentally compared with center launching method under different MMF links and then its wavelength division multiplexing (WDM) transmission performance is investigated. Experimental results indicate that the proposed mode conversion scheme could achieve better transmission performance and works well for the whole C-band.

  7. The "House" in Half Hollow Hills

    ERIC Educational Resources Information Center

    Karnilow, Sheldon

    2006-01-01

    In this article, the author relates how he initiated a systemic improvement to Half Hollow Hills school district when he became its superintendent. He relates that although he came to Half Hollow Hills with a deep understanding of the models of systemic change, he did not bring with him a specific prescriptive plan for improvement. His plan for…

  8. Beta Decay Half-Life of 84Mo

    NASA Astrophysics Data System (ADS)

    Stoker, J. B.; Mantica, P. F.; Bazin, D.; Bickley, A.; Becerril, A.; Crawford, H.; Cruse, K.; Estrade, A.; Mosby, M.; Guess, C. J.; Hitt, G. W.; Lorusso, G.; Matos, M.; Meharchand, R.; Minamisono, K.; Montes, F.; Pereira, J.; Perdikakis, G.; Pinter, J. S.; Schatz, H.; Vredevoogd, J.; Zegers, R. G. T.

    2008-10-01

    The β-decay half-life ^84Mo governs leakage out of the Zr-Nb cycle, a high temperature rp-process endpoint in x-ray binaries [1]. Treatment of the background and the poor statistics accumulated during the previous half-life measurement leave questions about statistical and systematic errors. We have remeasured the half-life of ^84Mo using a concerted setup of the NSCL β-Counting System [3] and 16 detectors from the Segmented Germanium Array [4]. We will report the half-life for ^84Mo, deduced using 40 times the previous sample size. The application of the NSCL RF Fragment Separator to remove unwanted isotopes, and hence reduce background for the half-life measurement, will also be discussed. [1] H. Schatz et al., Phys. Rep. 294, 167 1998 [2] P. Kienle et al., Prog. Part. Nuc. Phys. 46, 73 2001 [3] J. Prisciandaro et al., NIM A 505, 140 2003 [4] W. Mueller et al., NIM A 466, 492 2001 [5] D. Gorelov et al. PAC 2005, Knoxville, TN, May 16-20

  9. Half-lit Dione

    NASA Image and Video Library

    2017-10-16

    Saturn's moon Dione is captured in this view from NASA's Cassini spacecraft, half in shadow and half in light. Sinuous canyons carve interconnected paths across the moon's icy landscape. Subtle variations in brightness hint at differences in composition, as well as the size and shape of grains in Dione's surface material, or regolith. Cassini spent more than a decade at Saturn studying Dione (698 miles or 1,123 kilometers across) and the planet's many other moons as part of the quest to understand how the moons formed and evolved, and how they are connected. This view looks toward the side of Dione that faces away from Saturn. North is up and rotated 59 degrees to the right. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on June 22, 2017. The view was obtained at a distance of approximately 224,000 miles (360,000 kilometers) from Dione. Image scale is 1.4 mile (2.2 kilometers) per pixel. The Cassini spacecraft ended its mission on Sept. 15, 2017. https://photojournal.jpl.nasa.gov/catalog/PIA21349

  10. Historically Hottest Summers Projected to be the Norm for more than half of the World's Population by 2035

    NASA Astrophysics Data System (ADS)

    Mueller, B.; Zhang, X.; Zwiers, F. W.

    2015-12-01

    Global mean temperatures are projected to increase by 3K and 4.9K above pre-industrial levels by 2100 in a moderate stabilization and a high-emission scenario (RCP4.5 and RCP8.5 from CMIP5). However, warming rates are regionally different. In this presentation, we focus on the regions defined by the IPCC SREX report. We investigate the year in the future in which historically hottest summers are projected to become the norm, i.e. to occur at least every other year. Using results from a detection and attribution analysis, we provide probabilistic estimates based on RCP4.5 and RCP8.5 simulations constrained by observations during 1950-2012. We also estimate the fraction of attributable risk (FAR), i.e. the probability for hot summers that is attributable to past emissions of anthropogenic greenhouse gases and aerosols. We find that the FAR is larger than 0.9 in many regions. We project that under RCP4.5, more than half of the world's population will experience the historically hottest summer of the past 63 years with a probability of 50% and 90% by 2035 and 2050, respectively. Under the higher emission scenario RCP8.5, historically hottest summers are projected to be more wide-spread. The Mediterranean region, Western and Eastern Asia, Northern Eurasia and the Sahara are among the first regions for which such hot summers might become the norm. Even under RCP4.5, more than 90% of summers are projected to be hotter than the historically hottest summers by 2025 and 2035 for Sahara and the Mediterranean regions, respectively.

  11. RBC-/Cr-51/ half-life and albumin turnover in growing Beagle dogs during chronic radial acceleration

    NASA Technical Reports Server (NTRS)

    Beckman, D. A.; Evans, J. W.; Oyama, J.

    1979-01-01

    The effects of chronic centrifugation on growing Beagle dogs exposed to -2 or -2.6 Gx on albumin and RBC turnover rates, albumin concentration and space, and total blood volume were determined and compared with caged and run control of animals. Albumin-(I-125) and autologous RBC-(Cr-51) preparations were injected into all dogs at day 82 of the centrifugation periods, and the disappearance curves were determined by successive bleedings of the animals over the next 35 d, during which the centrifugation was continued. There were no differences in albumin turnover rates or space. Two populations of RBCs were found in both centrifugated groups, one with a normal half-life of 27 + or - 1 S.E.M. d, and one with a significantly (p less than 0.01) shorter half-life of 15 + or - 2 S.E.M. d. An absolute polycythemia was also observed in both centrifuged groups. The results suggest that chronic centrifugation acts through some as-yet unknown mechanism to affect RBC population kinetics.

  12. Half-life of Xe120

    NASA Astrophysics Data System (ADS)

    Phillips, A. A.; Andreoiu, C.; Ball, G. C.; Bandyopadhyay, D.; Behr, J. A.; Chupp, T. E.; Finlay, P.; Garrett, P. E.; Grinyer, G. F.; Hackman, G.; Hayden, M. E.; Hyland, B.; Nuss-Warren, S. R.; Pearson, M. R.; Schumaker, M. A.; Smith, M. B.; Svensson, C. E.; Tardiff, E. R.; Valiente-Dobón, J. J.; Warner, T.

    2006-08-01

    We have measured the half-life of Xe120 using a high-purity germanium (HPGe) detector to monitor the 176, 178, and 762 keV γ rays from Xe120 β+ decay. The result, 46±0.6 min, differs significantly from the value 40±1 min reported by Andersson [Ark. Fys. 28, 37 (1964)]. We have also measured the half-lives of Cs120 and I120 to be 60±0.7 s and 82.1±0.6 min, respectively, both of which are consistent with previous measurements.

  13. From individual spiking neurons to population behavior: Systematic elimination of short-wavelength spatial modes

    NASA Astrophysics Data System (ADS)

    Steyn-Ross, Moira L.; Steyn-Ross, D. A.

    2016-02-01

    Mean-field models of the brain approximate spiking dynamics by assuming that each neuron responds to its neighbors via a naive spatial average that neglects local fluctuations and correlations in firing activity. In this paper we address this issue by introducing a rigorous formalism to enable spatial coarse-graining of spiking dynamics, scaling from the microscopic level of a single type 1 (integrator) neuron to a macroscopic assembly of spiking neurons that are interconnected by chemical synapses and nearest-neighbor gap junctions. Spiking behavior at the single-neuron scale ℓ ≈10 μ m is described by Wilson's two-variable conductance-based equations [H. R. Wilson, J. Theor. Biol. 200, 375 (1999), 10.1006/jtbi.1999.1002], driven by fields of incoming neural activity from neighboring neurons. We map these equations to a coarser spatial resolution of grid length B ℓ , with B ≫1 being the blocking ratio linking micro and macro scales. Our method systematically eliminates high-frequency (short-wavelength) spatial modes q ⃗ in favor of low-frequency spatial modes Q ⃗ using an adiabatic elimination procedure that has been shown to be equivalent to the path-integral coarse graining applied to renormalization group theory of critical phenomena. This bottom-up neural regridding allows us to track the percolation of synaptic and ion-channel noise from the single neuron up to the scale of macroscopic population-average variables. Anticipated applications of neural regridding include extraction of the current-to-firing-rate transfer function, investigation of fluctuation criticality near phase-transition tipping points, determination of spatial scaling laws for avalanche events, and prediction of the spatial extent of self-organized macrocolumnar structures. As a first-order exemplar of the method, we recover nonlinear corrections for a coarse-grained Wilson spiking neuron embedded in a network of identical diffusively coupled neurons whose chemical synapses have

  14. PLC-based mode multi/demultiplexers for mode division multiplexing

    NASA Astrophysics Data System (ADS)

    Saitoh, Kunimasa; Hanzawa, Nobutomo; Sakamoto, Taiji; Fujisawa, Takeshi; Yamashita, Yoko; Matsui, Takashi; Tsujikawa, Kyozo; Nakajima, Kazuhide

    2017-02-01

    Recently developed PLC-based mode multi/demultiplexers (MUX/DEMUXs) for mode division multiplexing (MDM) transmission are reviewed. We firstly show the operation principle and basic characteristics of PLC-based MUX/DEMUXs with an asymmetric directional coupler (ADC). We then demonstrate the 3-mode (2LP-mode) multiplexing of the LP01, LP11a, and LP11b modes by using fabricated PLC-based mode MUX/DEMUX on one chip. In order to excite LP11b mode in the same plane, a PLC-based LP11 mode rotator is introduced. Finally, we show the PLC-based 6-mode (4LP-mode) MUX/DEMUX with a uniform height by using ADCs, LP11 mode rotators, and tapered waveguides. It is shown that the LP21a mode can be excited from the LP11b mode by using ADC, and the two nearly degenerated LP21b and LP02 modes can be (de)multiplexed separately by using tapered mode converter from E13 (E31) mode to LP21b (LP02) mode.

  15. Mate choice theory and the mode of selection in sexual populations.

    PubMed

    Carson, Hampton L

    2003-05-27

    Indirect new data imply that mate and/or gamete choice are major selective forces driving genetic change in sexual populations. The system dictates nonrandom mating, an evolutionary process requiring both revised genetic theory and new data on heritability of characters underlying Darwinian fitness. Successfully reproducing individuals represent rare selections from among vigorous, competing survivors of preadult natural selection. Nonrandom mating has correlated demographic effects: reduced effective population size, inbreeding, low gene flow, and emphasis on deme structure. Characters involved in choice behavior at reproduction appear based on quantitative trait loci. This variability serves selection for fitness within the population, having only an incidental relationship to the origin of genetically based reproductive isolation between populations. The claim that extensive hybridization experiments with Drosophila indicate that selection favors a gradual progression of "isolating mechanisms" is flawed, because intra-group random mating is assumed. Over deep time, local sexual populations are strong, independent genetic systems that use rich fields of variable polygenic components of fitness. The sexual reproduction system thus particularizes, in small subspecific populations, the genetic basis of the grand adaptive sweep of selective evolutionary change, much as Darwin proposed.

  16. Late recurrences of germ cell malignancies: a population-based experience over three decades

    PubMed Central

    Oldenburg, J; Alfsen, G C; Wæhre, H; Fosså, S D

    2006-01-01

    The purpose of this study was to explore the incidence of late relapse in patients with malignant germ cell tumour (MGCT) in a population-based series, with emphasis on the mode of detection, survival, and the relevance of histological findings. The clinical records from a population-based cohort of patients with seminoma (n=1123) or non-seminoma (n=826) were evaluated for late relapses. Twenty-five patients developed a late relapse. The cumulative 10-year incidence rate was 1.3%. All 10 seminoma patients, but only eight of 15 non-seminoma patients relapsed with vital malignant tumour (P=0.02). Teratoma or necrosis was found in seven of nine primarily chemotherapy-treated non-seminoma patients with normal tumour markers at late relapse. Six of nine patients operated with limited retroperitoneal lymph node dissection as part of the primary treatment had relapsed retroperitoneally outside the original operation field. The 10-year cause-specific survival was 68% in all patients, 50% in patients relapsing with vital malignant tumour and 100% in those with teratoma/ necrosis before or after salvage chemotherapy. The 10-year incidence rate of late relapses of 1.3% might reflect the true incidence rate in a population-based cohort of MGCT patients, with cure in at least half of them. PMID:16508636

  17. A fuzzy Petri-net-based mode identification algorithm for fault diagnosis of complex systems

    NASA Astrophysics Data System (ADS)

    Propes, Nicholas C.; Vachtsevanos, George

    2003-08-01

    Complex dynamical systems such as aircraft, manufacturing systems, chillers, motor vehicles, submarines, etc. exhibit continuous and event-driven dynamics. These systems undergo several discrete operating modes from startup to shutdown. For example, a certain shipboard system may be operating at half load or full load or may be at start-up or shutdown. Of particular interest are extreme or "shock" operating conditions, which tend to severely impact fault diagnosis or the progression of a fault leading to a failure. Fault conditions are strongly dependent on the operating mode. Therefore, it is essential that in any diagnostic/prognostic architecture, the operating mode be identified as accurately as possible so that such functions as feature extraction, diagnostics, prognostics, etc. can be correlated with the predominant operating conditions. This paper introduces a mode identification methodology that incorporates both time- and event-driven information about the process. A fuzzy Petri net is used to represent the possible successive mode transitions and to detect events from processed sensor signals signifying a mode change. The operating mode is initialized and verified by analysis of the time-driven dynamics through a fuzzy logic classifier. An evidence combiner module is used to combine the results from both the fuzzy Petri net and the fuzzy logic classifier to determine the mode. Unlike most event-driven mode identifiers, this architecture will provide automatic mode initialization through the fuzzy logic classifier and robustness through the combining of evidence of the two algorithms. The mode identification methodology is applied to an AC Plant typically found as a component of a shipboard system.

  18. Effect of survey mode on response patterns: comparison of face-to-face and self-administered modes in health surveys.

    PubMed

    Christensen, Anne Illemann; Ekholm, Ola; Glümer, Charlotte; Juel, Knud

    2014-04-01

    While face-to-face interviews are considered the gold standard of survey modes, self-administered questionnaires are often preferred for cost and convenience. This article examines response patterns in two general population health surveys carried out by face-to-face interview and self-administered questionnaire, respectively. Data derives from a health interview survey in the Region of Southern Denmark (face-to-face interview) and The Danish Health and Morbidity Survey 2010 (self-administered questionnaire). Identical questions were used in both surveys. Data on all individuals were obtained from administrative registers and linked to survey data at individual level. Multiple logistic regression analyses were used to examine the effect of survey mode on response patterns. The non-response rate was higher in the self-administered survey (37.9%) than in the face-to-face interview survey (23.7%). Marital status, ethnic background and highest completed education were associated with non-response in both modes. Furthermore, sex and age were associated with non-response in the self-administered mode. No significant mode effects were observed for indicators related to use of health services, but significant mode effects were observed for indicators related to self-reported health-related quality of life, health behaviour, social relations and morbidity (long-standing illness). The same factors were generally associated with non-response in both modes. Indicators based on factual questions with simple answers categories were overall more comparable according to mode than indicators based on questions that involved more subjective assessments. Other measures such as efficiency and cost-effectiveness of the mode should also be considered when determining the most appropriate form of data collection.

  19. Binding Modes of Ligands Using Enhanced Sampling (BLUES): Rapid Decorrelation of Ligand Binding Modes via Nonequilibrium Candidate Monte Carlo.

    PubMed

    Gill, Samuel C; Lim, Nathan M; Grinaway, Patrick B; Rustenburg, Ariën S; Fass, Josh; Ross, Gregory A; Chodera, John D; Mobley, David L

    2018-05-31

    Accurately predicting protein-ligand binding affinities and binding modes is a major goal in computational chemistry, but even the prediction of ligand binding modes in proteins poses major challenges. Here, we focus on solving the binding mode prediction problem for rigid fragments. That is, we focus on computing the dominant placement, conformation, and orientations of a relatively rigid, fragment-like ligand in a receptor, and the populations of the multiple binding modes which may be relevant. This problem is important in its own right, but is even more timely given the recent success of alchemical free energy calculations. Alchemical calculations are increasingly used to predict binding free energies of ligands to receptors. However, the accuracy of these calculations is dependent on proper sampling of the relevant ligand binding modes. Unfortunately, ligand binding modes may often be uncertain, hard to predict, and/or slow to interconvert on simulation time scales, so proper sampling with current techniques can require prohibitively long simulations. We need new methods which dramatically improve sampling of ligand binding modes. Here, we develop and apply a nonequilibrium candidate Monte Carlo (NCMC) method to improve sampling of ligand binding modes. In this technique, the ligand is rotated and subsequently allowed to relax in its new position through alchemical perturbation before accepting or rejecting the rotation and relaxation as a nonequilibrium Monte Carlo move. When applied to a T4 lysozyme model binding system, this NCMC method shows over 2 orders of magnitude improvement in binding mode sampling efficiency compared to a brute force molecular dynamics simulation. This is a first step toward applying this methodology to pharmaceutically relevant binding of fragments and, eventually, drug-like molecules. We are making this approach available via our new Binding modes of ligands using enhanced sampling (BLUES) package which is freely available on GitHub.

  20. Incidence and Classification of New-Onset Epilepsy and Epilepsy Syndromes in Children in Olmsted County, Minnesota from 1980–2004: A population-based study

    PubMed Central

    Wirrell, Elaine C.; Grossardt, Brandon R.; Wong-Kisiel, Lily C.-L.; Nickels, Katherine C.

    2012-01-01

    Purpose To determine the incidence and classification of new-onset epilepsy, as well as the distribution of epilepsy syndromes in a population-based group of children, using the newly proposed Report of the ILAE Commission on Classification and Terminology 2005–2009. Methods We identified all children residing in Olmsted County, MN, 1 month through 17 years with newly diagnosed epilepsy from 1980–2004. For each patient, epilepsy was classified into mode of onset, etiology, and syndrome or constellation (if present). Incidence rates were calculated overall and also separately for categories of mode of onset and etiology. Results The adjusted incidence rate of new-onset epilepsy in children was 44.5 cases per 100,000 persons per year. Incidence rates were highest in the first year of life and diminished with age. Mode of onset was focal in 68%, generalized/bilateral in 23%, spasms in 3% and unknown in 5%. Approximately half of children had an unknown etiology for their epilepsy, and of the remainder, 78 (22%) were genetic and 101 (28%) were structural/metabolic. A specific epilepsy syndrome could be defined at initial diagnosis in 99/359 (28%) children, but only 9/359 (3%) had a defined constellation. Conclusion Nearly half of childhood epilepsy is of “unknown” etiology. While a small proportion of this group met criteria for a known epilepsy syndrome, 41% of all childhood epilepsy is of “unknown” cause with no clear syndrome identified. Further work is needed to define more specific etiologies for this group. PMID:21482075

  1. Mode coupling at connectors in mode-division multiplexed transmission over few-mode fiber.

    PubMed

    Vuong, Jordi; Ramantanis, Petros; Frignac, Yann; Salsi, Massimiliano; Genevaux, Philippe; Bendimerad, Djalal F; Charlet, Gabriel

    2015-01-26

    In mode-division multiplexed (MDM) transmission systems, mode coupling is responsible for inter-modal crosstalk. We consider the transmission of modulated signals over a few-mode fiber (FMF) having low mode coupling and large differential mode group delay in the presence of a non-ideal fiber connection responsible for extra mode coupling. In this context, we first analytically derive the coupling matrix of the multimode connector and we numerically study the dependence of the matrix coefficients as a function of the butt-joint connection characteristics. The numerical results are then validated through an experiment with a five-mode setup. Finally, through numerical simulations, we assess the impact of the connector on the signal quality investigating different receiver digital signal processing (DSP) schemes.

  2. Impact of energetic-particle-driven geodesic acoustic modes on turbulence.

    PubMed

    Zarzoso, D; Sarazin, Y; Garbet, X; Dumont, R; Strugarek, A; Abiteboul, J; Cartier-Michaud, T; Dif-Pradalier, G; Ghendrih, Ph; Grandgirard, V; Latu, G; Passeron, C; Thomine, O

    2013-03-22

    The impact on turbulent transport of geodesic acoustic modes excited by energetic particles is evidenced for the first time in flux-driven 5D gyrokinetic simulations using the Gysela code. Energetic geodesic acoustic modes (EGAMs) are excited in a regime with a transport barrier in the outer radial region. The interaction between EGAMs and turbulence is such that turbulent transport can be enhanced in the presence of EGAMs, with the subsequent destruction of the transport barrier. This scenario could be particularly critical in those plasmas, such as burning plasmas, exhibiting a rich population of suprathermal particles capable of exciting energetic modes.

  3. Terraced-heterostructure large-optical-cavity AlGaAs diode laser - A new type of high-power CW single-mode device

    NASA Technical Reports Server (NTRS)

    Botez, D.; Connolly, J. C.

    1982-01-01

    A new terraced lateral wave confining structure is obtained by liquid phase epitaxy over channeled substrates misoriented perpendicular to the channels' direction. Single spatial and longitudinal mode CW operation is achieved to 50 mW from one facet, in large spot sizes (2 x 7.5 micron, 1/e squared points in intensity) and narrow beams (6 deg x 23 deg), full width half-power). At 70 C ambient temperature CW lasing is obtained to 15 mW from one facet. Weak mode confinement in an asymmetric lateral waveguides provides discrimination against high-order mode oscillation.

  4. High performance p-type half-Heusler thermoelectric materials

    NASA Astrophysics Data System (ADS)

    Yu, Junjie; Xia, Kaiyang; Zhao, Xinbing; Zhu, Tiejun

    2018-03-01

    Half-Heusler compounds, which possess robust mechanical strength, good high temperature thermal stability and multifaceted physical properties, have been verified as a class of promising thermoelectric materials. During the last two decades, great progress has been made in half-Heusler thermoelectrics. In this review, we summarize some representative work of p-type half-Heusler materials, the thermoelectric performance of which has been remarkably enhanced in recent years. We introduce the features of the crystal and electronic structures of half-Heusler compounds, and successful strategies for optimizing electrical and thermal transport in the p-type RFeSb (R  =  V, Nb, Ta) and MCoSb (M  =  Ti, Zr, Hf) based systems, including band engineering, the formation of solid solutions and hierarchical phonon scattering. The outlook for future research directions of half-Heusler thermoelectrics is also presented.

  5. Optimization of few-mode-fiber based mode converter for mode division multiplexing transmission

    NASA Astrophysics Data System (ADS)

    Xie, Yiwei; Fu, Songnian; Zhang, Minming; Tang, M.; Shum, P.; Liu, Deming

    2013-10-01

    Few-mode-fiber (FMF) based mode division multiplexing (MDM) is a promising technique to further increase the transmission capacity of single mode fibers. We propose and numerically investigate a fiber-optical mode converter (MC) using long period gratings (LPGs) fabricated on the FMF by point-by-point CO2 laser inscription technique. In order to precisely excite three modes (LP01, LP11, and LP02), both untilted LPG and tilted LPG are comprehensively optimized through the length, index modulation depth, and tilt angle of the LPG in order to achieve a mode contrast ratio (MCR) of more than 20 dB with less wavelength dependence. It is found that the proposed MCs have obvious advantages of high MCR, low mode crosstalk, easy fabrication and maintenance, and compact size.

  6. Constraining primordial vector mode from B-mode polarization

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

    Saga, Shohei; Ichiki, Kiyotomo; Shiraishi, Maresuke, E-mail: saga.shohei@nagoya-u.jp, E-mail: maresuke.shiraishi@pd.infn.it, E-mail: ichiki@a.phys.nagoya-u.ac.jp

    The B-mode polarization spectrum of the Cosmic Microwave Background (CMB) may be the smoking gun of not only the primordial tensor mode but also of the primordial vector mode. If there exist nonzero vector-mode metric perturbations in the early Universe, they are known to be supported by anisotropic stress fluctuations of free-streaming particles such as neutrinos, and to create characteristic signatures on both the CMB temperature, E-mode, and B-mode polarization anisotropies. We place constraints on the properties of the primordial vector mode characterized by the vector-to-scalar ratio r{sub v} and the spectral index n{sub v} of the vector-shear power spectrum,more » from the Planck and BICEP2 B-mode data. We find that, for scale-invariant initial spectra, the ΛCDM model including the vector mode fits the data better than the model including the tensor mode. The difference in χ{sup 2} between the vector and tensor models is Δχ{sup 2} = 3.294, because, on large scales the vector mode generates smaller temperature fluctuations than the tensor mode, which is preferred for the data. In contrast, the tensor mode can fit the data set equally well if we allow a significantly blue-tilted spectrum. We find that the best-fitting tensor mode has a large blue tilt and leads to an indistinct reionization bump on larger angular scales. The slightly red-tilted vector mode supported by the current data set can also create O(10{sup -22})-Gauss magnetic fields at cosmological recombination. Our constraints should motivate research that considers models of the early Universe that involve the vector mode.« less

  7. Effect of feedback mode and task difficulty on quality of timing decisions in a zero-sum game.

    PubMed

    Tikuisis, Peter; Vartanian, Oshin; Mandel, David R

    2014-09-01

    The objective was to investigate the interaction between the mode of performance outcome feedback and task difficulty on timing decisions (i.e., when to act). Feedback is widely acknowledged to affect task performance. However, the extent to which feedback display mode and its impact on timing decisions is moderated by task difficulty remains largely unknown. Participants repeatedly engaged a zero-sum game involving silent duels with a computerized opponent and were given visual performance feedback after each engagement. They were sequentially tested on three different levels of task difficulty (low, intermediate, and high) in counterbalanced order. Half received relatively simple "inside view" binary outcome feedback, and the other half received complex "outside view" hit rate probability feedback. The key dependent variables were response time (i.e., time taken to make a decision) and survival outcome. When task difficulty was low to moderate, participants were more likely to learn and perform better from hit rate probability feedback than binary outcome feedback. However, better performance with hit rate feedback exacted a higher cognitive cost manifested by higher decision response time. The beneficial effect of hit rate probability feedback on timing decisions is partially moderated by task difficulty. Performance feedback mode should be judiciously chosen in relation to task difficulty for optimal performance in tasks involving timing decisions.

  8. Passively mode-locked Yb fiber laser with PbSe colloidal quantum dots as saturable absorber.

    PubMed

    Wei, Kaihua; Fan, Shanhui; Chen, Qingguang; Lai, Xiaomin

    2017-10-16

    A passively mode-locked Yb fiber laser using PbSe colloidal quantum dots (CQDs) as saturable absorber (SA) is experimentally demonstrated. An all-fiber experimental scheme was designed to understand the SA property of PbSe CQDs. The non-saturable loss, modulation depth, and saturable intensity of SA measured were 23%, 7%, and 12 MW/cm 2 , respectively. The PbSe CQDs were sandwiched in a fiber connector, which was further inserted into the Yb fiber laser for mode-locking. As the pump power up to 110 mW, the self-starting mode-locking pulses were observed. Under the pump power of 285 mW, a maximum average laser power with fundamental mode-locking operation was obtained to be 21.3 mW. In this situation, the pulse full width at half maximum (FWHM), pulse repetition rate, and spectral FWHM were measured to be 70 ps, 8.3 MHz, and 4.5 nm, respectively.

  9. Effects of sputtering mode on the microstructure and ionic conductivity of yttria-stabilized zirconia films

    NASA Astrophysics Data System (ADS)

    Yeh, Tsung-Her; Lin, Ruei-De; Cherng, Bo-Ruei; Cherng, Jyh-Shiarn

    2018-05-01

    The microstructure and ionic conductivity of reactively sputtered yttria-stabilized zirconia (YSZ) films are systematically studied. Those films were reactively sputtered in various sputtering modes using a closed-loop controlled system with plasma emission monitoring. A transition-mode sputtering corresponding to 45% of target poisoning produces a microstructure with ultrafine crystallites embedded in an amorphous matrix, which undergoes an abnormal grain growth upon annealing at 800 °C. At 500 °C, the measured ionic conductivity of this annealed film is higher, by about a half order of magnitude, than those of its poisoned-mode counterparts, which are in turn significantly higher than that of the YSZ bulk by about two orders of magnitude. The abnormally-grown ultra-large grain size of the film deposited in the transition mode and then annealed is believed to be responsible for the former comparison due to the suppression of the grain boundary blocking effect, while the latter comparison can be attributed to the interface effect.

  10. Spatial-mode switchable ring fiber laser based on low mode-crosstalk all-fiber mode MUX/DEMUX

    NASA Astrophysics Data System (ADS)

    Ren, Fang; Yu, Jinyi; Wang, Jianping

    2018-05-01

    We report an all-fiber ring laser that emits linearly polarized (LP) modes based on the intracavity all-fiber mode multiplexer/demultiplexer (MUX/DEMUX). Multiple LP modes in ring fiber laser are generated by taking advantage of mode MUX/DEMUX. The all-fiber mode MUX/DEMUX are composed of cascaded mode-selective couplers (MSCs). The output lasing mode of the ring fiber laser can be switched among the three lowest-order LP modes by employing combination of a mode MUX and a simple N × 1 optical switch. The slope efficiencies, optical spectra and mode profiles are measured.

  11. Demonstration of a High-Order Mode Input Coupler for a 220-GHz Confocal Gyrotron Traveling Wave Tube

    NASA Astrophysics Data System (ADS)

    Guan, Xiaotong; Fu, Wenjie; Yan, Yang

    2018-02-01

    A design of high-order mode input coupler for 220-GHz confocal gyrotron travelling wave tube is proposed, simulated, and demonstrated by experimental tests. This input coupler is designed to excite confocal TE 06 mode from rectangle waveguide TE 10 mode over a broadband frequency range. Simulation results predict that the optimized conversion loss is about 2.72 dB with a mode purity excess of 99%. Considering of the gyrotron interaction theory, an effective bandwidth of 5 GHz is obtained, in which the beam-wave coupling efficiency is higher than half of maximum. The field pattern under low power demonstrates that TE 06 mode is successfully excited in confocal waveguide at 220 GHz. Cold test results from the vector network analyzer perform good agreements with simulation results. Both simulation and experimental results illustrate that the reflection at input port S11 is sensitive to the perpendicular separation of two mirrors. It provides an engineering possibility for estimating the assembly precision.

  12. Partition functions with spin in AdS2 via quasinormal mode methods

    DOE PAGES

    Keeler, Cynthia; Lisbão, Pedro; Ng, Gim Seng

    2016-10-12

    We extend the results of [1], computing one loop partition functions for massive fields with spin half in AdS 2 using the quasinormal mode method proposed by Denef, Hartnoll, and Sachdev [2]. We find the finite representations of SO(2,1) for spin zero and spin half, consisting of a highest weight state |hi and descendants with non-unitary values of h. These finite representations capture the poles and zeroes of the one loop determinants. Together with the asymptotic behavior of the partition functions (which can be easily computed using a large mass heat kernel expansion), these are sufficient to determine the fullmore » answer for the one loop determinants. We also discuss extensions to higher dimensional AdS 2n and higher spins.« less

  13. Long-term clinical effects of ventricular pacing reduction with a changeover mode to minimize ventricular pacing in a general pacemaker population

    PubMed Central

    Stockburger, Martin; Boveda, Serge; Moreno, Javier; Da Costa, Antoine; Hatala, Robert; Brachmann, Johannes; Butter, Christian; Garcia Seara, Javier; Rolando, Mara; Defaye, Pascal

    2015-01-01

    Aim Right ventricular pacing (VP) has been hypothesized to increase the risk in heart failure (HF) and atrial fibrillation (AF). The ANSWER study evaluated, whether an AAI-DDD changeover mode to minimize VP (SafeR) improves outcome compared with DDD in a general dual-chamber pacemaker population. Methods and results ANSWER was a randomized controlled multicentre trial assessing SafeR vs. standard DDD in sinus node disease (SND) or AV block (AVB) patients. After a 1-month run-in period, they were randomized (1 : 1) and followed for 3 years. Pre-specified co-primary end-points were VP and the composite of hospitalization for HF, AF, or cardioversion. Pre-specified secondary end-points were cardiac death or HF hospitalizations and cardiovascular hospitalizations. ANSWER enrolled 650 patients (52.0% SND, 48% AVB) at 43 European centres and randomized in SafeR (n = 314) or DDD (n = 318). The SafeR mode showed a significant decrease in VP compared with DDD (11.5 vs. 93.6%, P < 0.0001 at 3 years). Deaths and syncope did not differ between randomization arms. No significant difference between groups [HR = 0.78; 95% CI (0.48–1.25); P = 0.30] was found in the time to event of the co-primary composite of hospitalization for HF, AF, or cardioversion, nor in the individual components. SafeR showed a 51% risk reduction (RR) in experiencing cardiac death or HF hospitalization [HR = 0.49; 95% CI (0.27–0.90); P = 0.02] and 30% RR in experiencing cardiovascular hospitalizations [HR = 0.70; 95% CI (0.49–1.00); P = 0.05]. Conclusion SafeR safely and significantly reduced VP in a general pacemaker population though had no effect on hospitalization for HF, AF, or cardioversion, when compared with DDD. PMID:25179761

  14. 1.55-μm mode-locked quantum-dot lasers with 300 MHz frequency tuning range

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

    Sadeev, T., E-mail: tagir@mailbox.tu-berlin.de; Arsenijević, D.; Bimberg, D.

    2015-01-19

    Passive mode-locking of two-section quantum-dot mode-locked lasers grown by metalorganic vapor phase epitaxy on InP is reported. 1250-μm long lasers exhibit a wide tuning range of 300 MHz around the fundamental mode-locking frequency of 33.48 GHz. The frequency tuning is achieved by varying the reverse bias of the saturable absorber from 0 to −2.2 V and the gain section current from 90 to 280 mA. 3 dB optical spectra width of 6–7 nm leads to ex-facet optical pulses with full-width half-maximum down to 3.7 ps. Single-section quantum-dot mode-locked lasers show 0.8 ps broad optical pulses after external fiber-based compression. Injection current tuning from 70 tomore » 300 mA leads to 30 MHz frequency tuning.« less

  15. High power single-longitudinal-mode Ho:YLF unidirectional ring laser based on a composite structure of acousto-optic device and wave plate

    NASA Astrophysics Data System (ADS)

    Dai, T. Y.; Fan, Z. G.; Wu, J.; Ju, Y. L.; Yao, B. Q.; Zhang, Z. G.; Teng, K.; Xu, X. G.; Duan, X. M.

    2017-05-01

    We report a unidirectional single-longitudinal-mode Ho:YLF ring laser. An acousto-optic modulator and two half-wave plates were used to enforce the Ho:YLF ring laser in a unidirectional operation. The single-longitudinal-mode output power could reach 3.73 W successfully when the incident pump power was 16.4 W. The corresponding slope efficiency was 27.1%. The wavelength of the single-longitudinal-mode Ho:YLF ring laser was 2063.8 nm. The M2 factor was 1.12. The results illustrated that the single-longitudinal-mode output power could be further enhanced by increasing the radio frequency power of the acousto-optic modulator.

  16. Aboriginal population prospects.

    PubMed

    Gray, A; Tesfaghiorghis, H

    1993-11-01

    The authors examine data from the 1986 and 1991 Australian censuses to assess discrepancies between the census data and past projections of the size and structure of the Aboriginal population. They also "comment on ways in which determinants of Aboriginal population change are diverging from the parameters used for previous projections. We pay particular attention to mortality prospects.... We note the evidence for under-enumeration of the Aboriginal population in particular age groups in the 1991 Census as in previous censuses, and estimate the size of adjustments necessary to correct for some, but not all, of these deficiencies. The analysis shows that Aboriginal fertility increased in the second half of the 1980s." excerpt

  17. Investigation of energetic particle induced geodesic acoustic mode

    NASA Astrophysics Data System (ADS)

    Schneller, Mirjam; Fu, Guoyong; Chavdarovski, Ilija; Wang, Weixing; Lauber, Philipp; Lu, Zhixin

    2017-10-01

    Energetic particles are ubiquitous in present and future tokamaks due to heating systems and fusion reactions. Anisotropy in the distribution function of the energetic particle population is able to excite oscillations from the continuous spectrum of geodesic acoustic modes (GAMs), which cannot be driven by plasma pressure gradients due to their toroidally and nearly poloidally symmetric structures. These oscillations are known as energetic particle-induced geodesic acoustic modes (EGAMs) [G.Y. Fu'08] and have been observed in recent experiments [R. Nazikian'08]. EGAMs are particularly attractive in the framework of turbulence regulation, since they lead to an oscillatory radial electric shear which can potentially saturate the turbulence. For the presented work, the nonlinear gyrokinetic, electrostatic, particle-in-cell code GTS [W.X. Wang'06] has been extended to include an energetic particle population following either bump-on-tail Maxwellian or slowing-down [Stix'76] distribution function. With this new tool, we study growth rate, frequency and mode structure of the EGAM in an ASDEX Upgrade-like scenario. A detailed understanding of EGAM excitation reveals essential for future studies of EGAM interaction with micro-turbulence. Funded by the Max Planck Princeton Research Center. Computational resources of MPCDF and NERSC are greatefully acknowledged.

  18. Wave energy transfer in elastic half-spaces with soft interlayers.

    PubMed

    Glushkov, Evgeny; Glushkova, Natalia; Fomenko, Sergey

    2015-04-01

    The paper deals with guided waves generated by a surface load in a coated elastic half-space. The analysis is based on the explicit integral and asymptotic expressions derived in terms of Green's matrix and given loads for both laminate and functionally graded substrates. To perform the energy analysis, explicit expressions for the time-averaged amount of energy transferred in the time-harmonic wave field by every excited guided or body wave through horizontal planes and lateral cylindrical surfaces have been also derived. The study is focused on the peculiarities of wave energy transmission in substrates with soft interlayers that serve as internal channels for the excited guided waves. The notable features of the source energy partitioning in such media are the domination of a single emerging mode in each consecutive frequency subrange and the appearance of reverse energy fluxes at certain frequencies. These effects as well as modal and spatial distribution of the wave energy coming from the source into the substructure are numerically analyzed and discussed.

  19. Plasmodium falciparum Founder Populations in Western Cambodia Have Reduced Artemisinin Sensitivity In Vitro

    PubMed Central

    Amaratunga, Chanaki; Witkowski, Benoit; Dek, Dalin; Try, Vorleak; Khim, Nimol; Miotto, Olivo

    2014-01-01

    Reduced Plasmodium falciparum sensitivity to short-course artemisinin (ART) monotherapy manifests as a long parasite clearance half-life. We recently defined three parasite founder populations with long half-lives in Pursat, western Cambodia, where reduced ART sensitivity is prevalent. Using the ring-stage survival assay, we show that these founder populations have reduced ART sensitivity in vitro at the early ring stage of parasite development and that a genetically admixed population contains subsets of parasites with normal or reduced ART sensitivity. PMID:24867977

  20. Teaching Multiple Modes of Representation in Middle-School Science Classrooms: Impact on Student Learning and Multimodal Use

    ERIC Educational Resources Information Center

    Nixon, Ryan S.; Smith, Leigh K.; Wimmer, Jennifer J.

    2015-01-01

    This quasi-experimental study investigated how explicit instruction about multiple modes of representation (MMR) impacted grades 7 (n = 61) and 8 (n = 141) students' learning and multimodal use on end-of-unit assessments. Half of each teacher's (n = 3) students received an intervention consisting of explicit instruction on MMR in science…

  1. Mixed-mode oscillations and chaos in a prey-predator system with dormancy of predators.

    PubMed

    Kuwamura, Masataka; Chiba, Hayato

    2009-12-01

    It is shown that the dormancy of predators induces mixed-mode oscillations and chaos in the population dynamics of a prey-predator system under certain conditions. The mixed-mode oscillations and chaos are shown to bifurcate from a coexisting equilibrium by means of the theory of fast-slow systems. These results may help to find experimental conditions under which one can demonstrate chaotic population dynamics in a simple phytoplankton-zooplankton (-resting eggs) community in a microcosm with a short duration.

  2. When do star clusters become multiple star systems? II. Toward a half-life formalism with four bodies

    NASA Astrophysics Data System (ADS)

    Ibragimov, Timur; Leigh, Nathan W. C.; Ryu, Taeho; Panurach, Teresa; Perna, Rosalba

    2018-03-01

    We present a half-life formalism for describing the disruption of gravitationally-bound few-body systems, with a focus on binary-binary scattering. For negative total encounter energies, the four-body problem has three possible decay products in the point particle limit. For each decay product and a given set of initial conditions, we obtain directly from numerical scattering simulations the half-life for the distribution of disruption times. As in radioactive decay, the half-lives should provide a direct prediction for the relative fractions of each decay product. We test this prediction with simulated data and find good agreement with our hypothesis. We briefly discuss applications of this feature of the gravitational four-body problem to populations of black holes in globular clusters. This paper, the second in the series, builds on extending the remarkable similarity between gravitational chaos at the macroscopic scale and radioactive decay at the microscopic scale to larger-N systems.

  3. When do star clusters become multiple star systems? II. Towards a half-life formalism with four bodies

    NASA Astrophysics Data System (ADS)

    Ibragimov, Timur; Leigh, Nathan W. C.; Ryu, Taeho; Panurach, Teresa; Perna, Rosalba

    2018-07-01

    We present a half-life formalism for describing the disruption of gravitationally bound few-body systems, with a focus on binary-binary scattering. For negative total encounter energies, the four-body problem has three possible decay products in the point-particle limit. For each decay product and a given set of initial conditions, we obtain directly from numerical scattering simulations the half-life for the distribution of disruption times. As in radioactive decay, the half-lives should provide a direct prediction for the relative fractions of each decay product. We test this prediction with simulated data and find good agreement with our hypothesis. We briefly discuss applications of this feature of the gravitational four-body problem to populations of black holes in globular clusters. This paper, the second in the series, builds on extending the remarkable similarity between gravitational chaos at the macroscopic scale and radioactive decay at the microscopic scale to larger-N systems.

  4. Mitigating leakage errors due to cavity modes in a superconducting quantum computer

    NASA Astrophysics Data System (ADS)

    McConkey, T. G.; Béjanin, J. H.; Earnest, C. T.; McRae, C. R. H.; Pagel, Z.; Rinehart, J. R.; Mariantoni, M.

    2018-07-01

    A practical quantum computer requires quantum bit (qubit) operations with low error probabilities in extensible architectures. We study a packaging method that makes it possible to address hundreds of superconducting qubits by means of coaxial Pogo pins. A qubit chip is housed in a superconducting box, where both box and chip dimensions lead to unwanted modes that can interfere with qubit operations. We analyze these interference effects in the context of qubit coherent leakage and qubit decoherence induced by damped modes. We propose two methods, half-wave fencing and antinode pinning, to mitigate the resulting errors by detuning the resonance frequency of the modes from the qubit frequency. We perform electromagnetic field simulations indicating that the resonance frequency of the modes increases with the number of installed pins and can be engineered to be significantly higher than the highest qubit frequency. We estimate that the error probabilities and decoherence rates due to suitably shifted modes in realistic scenarios can be up to two orders of magnitude lower than the state-of-the-art superconducting qubit error and decoherence rates. Our methods can be extended to different types of packages that do not rely on Pogo pins. Conductive bump bonds, for example, can serve the same purpose in qubit architectures based on flip chip technology. Metalized vias, instead, can be used to mitigate modes due to the increasing size of the dielectric substrate on which qubit arrays are patterned.

  5. Core-protective half-metallicity in trilayer graphene nanoribbons

    NASA Astrophysics Data System (ADS)

    Jeon, Gi Wan; Lee, Kyu Won; Lee, Cheol Eui

    2017-07-01

    Half-metals, playing an important role in spintronics, can be described as materials that enable fully spin-polarized electrical current. Taking place in graphene-based materials, half-metallicity has been shown in zigzag-edged graphene nanoribbons (ZGNRs) under an electric field. Localized electron states on the edge carbons are a key to enabling half-metallicity in ZGNRs. Thus, modification of the localized electron states is instrumental to the carbon-based spintronics. Our simple model shows that in a trilayer ZGNRs (triZGNRs) only the middle layer may become half-metallic leaving the outer layers insulating in an electric field, as confirmed by our density functional theory (DFT) calculations. Due to the different circumstances of the edge carbons, the electron energies at the edge carbons are different near the Fermi level, leading to a layer-selective half-metallicity. We believe that triZGNRs can be the tiniest electric cable (nanocable) form and can open a route to graphene-based spintronics applications.

  6. Nonlinear instability of half-solitons on star graphs

    NASA Astrophysics Data System (ADS)

    Kairzhan, Adilbek; Pelinovsky, Dmitry E.

    2018-06-01

    We consider a half-soliton stationary state of the nonlinear Schrödinger equation with the power nonlinearity on a star graph consisting of N edges and a single vertex. For the subcritical power nonlinearity, the half-soliton state is a degenerate critical point of the action functional under the mass constraint such that the second variation is nonnegative. By using normal forms, we prove that the degenerate critical point is a saddle point, for which the small perturbations to the half-soliton state grow slowly in time resulting in the nonlinear instability of the half-soliton state. The result holds for any N ≥ 3 and arbitrary subcritical power nonlinearity. It gives a precise dynamical characterization of the previous result of Adami et al. (2012) [2], where the half-soliton state was shown to be a saddle point of the action functional under the mass constraint for N = 3 and for cubic nonlinearity.

  7. Elevation or Suppression? The Resolved Star Formation Main Sequence of Galaxies with Two Different Assembly Modes

    NASA Astrophysics Data System (ADS)

    Liu, Qing; Wang, Enci; Lin, Zesen; Gao, Yulong; Liu, Haiyang; Berhane Teklu, Berzaf; Kong, Xu

    2018-04-01

    We investigate the spatially resolved star formation main sequence in star-forming galaxies using Integral Field Spectroscopic observations from the Mapping Nearby Galaxies at the Apache Point Observatory survey. We demonstrate that the correlation between the stellar mass surface density (Σ*) and star formation rate surface density (ΣSFR) holds down to the sub-galactic scale, leading to the sub-galactic main sequence (SGMS). By dividing galaxies into two populations based on their recent mass assembly modes, we find the resolved main sequence in galaxies with the “outside-in” mode is steeper than that in galaxies with the “inside-out” mode. This is also confirmed on a galaxy-by-galaxy level, where we find the distributions of SGMS slopes for individual galaxies are clearly separated for the two populations. When normalizing and stacking the SGMS of individual galaxies on one panel for the two populations, we find that the inner regions of galaxies with the “inside-out” mode statistically exhibit a suppression in star formation, with a less significant trend in the outer regions of galaxies with the “outside-in” mode. In contrast, the inner regions of galaxies with “outside-in” mode and the outer regions of galaxies with “inside-out” mode follow a slightly sublinear scaling relation with a slope ∼0.9, which is in good agreement with previous findings, suggesting that they are experiencing a universal regulation without influences of additional physical processes.

  8. An analysis of the Hubble Space Telescope fine guidance sensor fine lock mode

    NASA Technical Reports Server (NTRS)

    Taff, L. G.

    1991-01-01

    There are two guiding modes of the Hubble Space Telescope (HST) used for the acquisition of astronomical data by one of its six scientific instruments. The more precise one is called Fine Lock. Command and control problems in the onboard electronics has limited Fine Lock to brighter stars, V less than 13.0 mag, instead of fulfilling its goal of V = 14.5 mag. Consequently, the less precise guiding mode of Coarse Track (approximately 40 milli-arc seconds) has to be used fairly frequently. Indeed, almost half of the scientific observations to have been made with the HST will be compromised. The only realistic or extensive simulations of the Fine Lock guidance mode are reported. The theoretical analysis underlying the Monte Carlo experiments and the numerical computations clearly show both that the control electronics are severely under-engineered and how to adjust the various control parameters to successfully extend Fine Lock guiding performance back to V = 14.0 mag and sometimes beyond.

  9. First Compilation and Evaluation of Beta-Delayed Neutron Emission Probabilities and Associated Half-Lives for A ≤72 Nuclei

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

    Birch, M.; Singh, B.; Abriola, D.

    2014-06-01

    After a comprehensive compilation and evaluation of beta-delayed neutron (β -n) emission probabilities, P n, and associated half-lives for A ≤ 72 nuclei has been performed for the first time. The recommended values have been used to analyze the systematics of β -nemission in this region. The ratio P n/T 1/2 is better correlated with the Q-value of the β -n decay mode than the previously proposed Kratz-Herrmann Formula (KHF). Moreover, the recommended values are also compared with theoretical quasi-particle random phase approximation (QRPA) calculations.

  10. An SMS (single mode - multi mode - single mode) fiber structure for vibration sensing

    NASA Astrophysics Data System (ADS)

    Waluyo, T. B.; Bayuwati, D.

    2017-04-01

    We describe an SMS (single mode - multi mode - single mode) fiber structure to be used in a vibration sensing system. The fiber structure was fabricated by splicing a section (about 300 mm in length) of a step index multi mode fiber between two single mode fibers obtained from a communication grade fiber patchcord. Interference between higher order modes occurs while light from a narrow band light source travels along the multi mode fiber. When the multi mode fiber vibrates, the refractive index profile is changed because of the photo-elastics effect and the amplitude of the interference pattern is changed accordingly. To simulate a vibrating structure we used a loudspeaker to vibrate a wooden table. By using a digital oscilloscope, we recorded and analysed the vibrating signals obtained from the SMS fiber structure as well as from a GS-32CT geophone for referencing. We observed that this SMS fiber structure was potential to be used in a vibration sensing system with a measurement range from 30 to 180 Hz with inherent optical fiber sensor advantages such as light weight, immune to electromagnetic interference, and no electricity in the sensing part.

  11. Dual comb generation from a mode-locked fiber laser with orthogonally polarized interlaced pulses.

    PubMed

    Akosman, Ahmet E; Sander, Michelle Y

    2017-08-07

    Ultra-high precision dual-comb spectroscopy traditionally requires two mode-locked, fully stabilized lasers with complex feedback electronics. We present a novel mode-locked operation regime in a thulium-holmium co-doped fiber laser, a frequency-halved state with orthogonally polarized interlaced pulses, for dual comb generation from a single source. In a linear fiber laser cavity, an ultrafast pulse train composed of co-generated, equal intensity and orthogonally polarized consecutive pulses at half of the fundamental repetition rate is demonstrated based on vector solitons. Upon optical interference of the orthogonally polarized pulse trains, two stable microwave RF beat combs are formed, effectively down-converting the optical properties into the microwave regime. These co-generated, dual polarization interlaced pulse trains, from one all-fiber laser configuration with common mode suppression, thus provide an attractive compact source for dual-comb spectroscopy, optical metrology and polarization entanglement measurements.

  12. Aetiology of congenital and paediatric cataract in an Australian population

    PubMed Central

    Wirth, M G; Russell-Eggitt, I M; Craig, J E; Elder, J E; Mackey, D A

    2002-01-01

    Background/aim: Paediatric cataract is a major cause of childhood blindness. Several genes associated with congenital and paediatric cataracts have been identified. The aim was to determine the incidence of cataract in a population, the proportion of hereditary cataracts, the mode of inheritance, and the clinical presentation. Methods: The Royal Children's Hospital and the Royal Victorian Eye and Ear Hospital have a referral base for almost all paediatric patients with cataracts in south eastern Australia. The database contains cases seen over the past 25 years. The medical histories of these patients were reviewed. Results: 421 patients with paediatric cataract were identified, which gives an estimated incidence of 2.2 per 10 000 births. Of the 342 affected individuals with a negative family history, 50% were diagnosed during the first year of life, and 56/342 (16%) were associated with a recognised systemic disease or syndrome. Unilateral cataract was identified in 178/342 (52%) of sporadic cases. 79 children (from 54 nuclear families) had a positive family history. Of these 54 families, 45 were recruited for clinical examination and DNA collection. Ten nuclear families were subsequently found to be related, resulting in four larger pedigrees. Thus, 39 families have been studied. The mode of inheritance was autosomal dominant in 30 families, X linked in four, autosomal recessive in two, and uncertain in three. In total, 178 affected family members were examined; of these 8% presented with unilateral cataracts and 43% were diagnosed within the first year of life. Conclusions: In the paediatric cataract population examined, approximately half of the patients were diagnosed in the first year of life. More than 18% had a positive family history of cataracts. Of patients with hereditary cataracts 8% presented with unilateral involvement. Identification of the genes that cause paediatric and congenital cataract should help clarify the aetiology of some sporadic and

  13. Chiral Majorana fermion modes in a quantum anomalous Hall insulator-superconductor structure.

    PubMed

    He, Qing Lin; Pan, Lei; Stern, Alexander L; Burks, Edward C; Che, Xiaoyu; Yin, Gen; Wang, Jing; Lian, Biao; Zhou, Quan; Choi, Eun Sang; Murata, Koichi; Kou, Xufeng; Chen, Zhijie; Nie, Tianxiao; Shao, Qiming; Fan, Yabin; Zhang, Shou-Cheng; Liu, Kai; Xia, Jing; Wang, Kang L

    2017-07-21

    Majorana fermion is a hypothetical particle that is its own antiparticle. We report transport measurements that suggest the existence of one-dimensional chiral Majorana fermion modes in the hybrid system of a quantum anomalous Hall insulator thin film coupled with a superconductor. As the external magnetic field is swept, half-integer quantized conductance plateaus are observed at the locations of magnetization reversals, giving a distinct signature of the Majorana fermion modes. This transport signature is reproducible over many magnetic field sweeps and appears at different temperatures. This finding may open up an avenue to control Majorana fermions for implementing robust topological quantum computing. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  14. Musical and linguistic listening modes in the speech-to-song illusion bias timing perception and absolute pitch memory.

    PubMed

    Graber, Emily; Simchy-Gross, Rhimmon; Margulis, Elizabeth Hellmuth

    2017-12-01

    The speech-to-song (STS) illusion is a phenomenon in which some spoken utterances perceptually transform to song after repetition [Deutsch, Henthorn, and Lapidis (2011). J. Acoust. Soc. Am. 129, 2245-2252]. Tierney, Dick, Deutsch, and Sereno [(2013). Cereb. Cortex. 23, 249-254] developed a set of stimuli where half tend to transform to perceived song with repetition and half do not. Those that transform and those that do not can be understood to induce a musical or linguistic mode of listening, respectively. By comparing performance on perceptual tasks related to transforming and non-transforming utterances, the current study examines whether the musical mode of listening entails higher sensitivity to temporal regularity and better absolute pitch (AP) memory compared to the linguistic mode. In experiment 1, inter-stimulus intervals within STS trials were steady, slightly variable, or highly variable. Participants reported how temporally regular utterance entrances were. In experiment 2, participants performed an AP memory task after a blocked STS exposure phase. Utterances identically matching those used in the exposure phase were targets among transposed distractors in the test phase. Results indicate that listeners exhibit heightened awareness of temporal manipulations but reduced awareness of AP manipulations to transforming utterances. This methodology establishes a framework for implicitly differentiating musical from linguistic perception.

  15. Passive mode-locking of 3.25μm GaSb-based type-I quantum-well cascade diode lasers

    NASA Astrophysics Data System (ADS)

    Feng, Tao; Shterengas, Leon; Kipshidze, Gela; Hosoda, Takashi; Wang, Meng; Belenky, Gregory

    2018-02-01

    Passively mode-locked type-I quantum well cascade diode lasers emitting in the methane absorption band near 3.25 μm were designed, fabricated and characterized. The deep etched 5.5-μm-wide single spatial mode ridge waveguide design utilizing split-contact architecture was implemented. The devices with absorber to gain section length ratios of 11% and 5.5% were studied. Lasers with the longer absorber section ( 300 μm) generated smooth bell-shape-like emission spectrum with about 30 lasing modes at full-width-at-half-maximum level. Devices with reverse biased absorber section demonstrated stable radio frequency beat with nearly perfect Lorentzian shape over four orders of magnitude of intensity. The estimated pulse-to-pulse timing jitter was about 110 fs/cycle. Laser generated average power of more than 1 mW in mode-locked regime.

  16. Outlier detection in a new half-circular distribution

    NASA Astrophysics Data System (ADS)

    Rambli, Adzhar; Mohamed, Ibrahim Bin; Shimizu, Kunio; Khalidin, Nurliza

    2015-10-01

    In this paper, we use a discordancy test based on spacing theory to detect outlier in a half-circular data. Up to now, numerous discordancy tests have been proposed to detect outlier in circular distributions which are defined in [0,2π). However, some circular data lie within just half of this range. Therefore, first we introduce a new half-circular distribution developed using the inverse stereographic projection technique on a gamma distributed variable. Then, we develop a new discordancy test to detect single or multiple outliers in the half-circular data based on the spacing theory. We show the practical value of the test by applying it to an eye data set obtained from a glaucoma clinic at the University of Malaya Medical Centre, Malaysia.

  17. Factors associated with mode of colorectal cancer detection and time to diagnosis: a population level study.

    PubMed

    Sikdar, Khokan C; Dickinson, James; Winget, Marcy

    2017-01-05

    Although it is well-known that early detection of colorectal cancer (CRC) is important for optimal patient survival, the relationship of patient and health system factors with delayed diagnosis are unclear. The purpose of this study was to identify the demographic, clinical and healthcare factors related to mode of CRC detection and length of the diagnostic interval. All residents of Alberta, Canada diagnosed with first-ever incident CRC in years 2004-2010 were identified from the Alberta Cancer Registry. Population-based administrative health datasets, including hospital discharge abstract, ambulatory care classification system and physician billing data, were used to identify healthcare services related to CRC diagnosis. The time to diagnosis was defined as the time from the first CRC-related healthcare visit to the date of CRC diagnosis. Mode of CRC detection was classified into three groups: urgent, screen-detected and symptomatic. Quantile regression was performed to assess factors associated with time to diagnosis. 9626 patients were included in the study; 25% of patients presented as urgent, 32% were screen-detected and 43% were symptomatic. The median time to diagnosis for urgent, screen-detected and symptomatic patients were 6 days (interquartile range (IQR) 2-14 days), 74 days (IQR 36-183 days), 84 days (IQR 39-223 days), respectively. Time to diagnosis was greater than 6 months for 27% of non-urgent patients. Healthcare factors had the largest impact on time to diagnosis: 3 or more visits to a GP increased the median by 140 days whereas 2 or more visits to a GI-specialist increased it by 108 days compared to 0-1 visits to a GP or GI-specialist, respectively. A large proportion of CRC patients required urgent work-up or had to wait more than 6 months for diagnosis. Actions are needed to reduce the frequency of urgent presentation as well as improve the timeliness of diagnosis. Findings suggest a need to improve coordination of care across multiple

  18. Half Sinful Words: Disguised Grief in "Ulysses."

    ERIC Educational Resources Information Center

    Hobbs, Michael

    As a shrewd technician of the language, A. L. Tennyson rightly understood that words are not controllable; they do not always obey rules. As Tennyson said, words "half reveal and half conceal the soul within." In "Ulysses," the title character's speech to his fellow mariners--where he attempts to explain why he has decided to…

  19. Precision Half-life Measurement of 25Al

    NASA Astrophysics Data System (ADS)

    Long, Jacob; Ahn, Tan; Allen, Jacob; Bardayan, Daniel; Becchetti, Fredrich; Blankstein, Drew; Brodeur, Maxime; Burdette, Daniel; Frentz, Bryce; Hall, Matthew; Kelly, James; Kolata, James; O'Malley, Patrick; Schultz, Bradley; Strauss, Sabrina; Valverde, Adrian; TwinSol Collaboration

    2017-09-01

    In recent years, precision measurements have led to considerable advances in several areas of physics, including fundamental symmetry. Precise determination of ft values for superallowed mixed transitions between mirror nuclides could provide an avenue to test the theoretical corrections used to extract the Vud matrix element from superallowed pure Fermi transitions. Calculation of the ft value requires the half-life, branching ratio, and Q value. 25Al decay is of particular interest as its half-life is derived from a series of conflicting measurements, and the largest uncertainty on the ft value stems from the half-life uncertainty. The life-time was determined by the β counting of implanted 25Al on a Ta foil that was removed from the beam for counting. The 25Al beam was produced by a transfer reaction and separated by the TwinSol facility of the Nuclear Science Laboratory of the University of Notre Dame. The 25Al results will be presented with preliminary results of more recent half-life measurements. The National Science Foundation.

  20. Computational Fluid Dynamics (CFD) Simulation of Hypersonic Turbine-Based Combined-Cycle (TBCC) Inlet Mode Transition

    NASA Technical Reports Server (NTRS)

    Slater, John W.; Saunders, John D.

    2010-01-01

    Methods of computational fluid dynamics were applied to simulate the aerodynamics within the turbine flowpath of a turbine-based combined-cycle propulsion system during inlet mode transition at Mach 4. Inlet mode transition involved the rotation of a splitter cowl to close the turbine flowpath to allow the full operation of a parallel dual-mode ramjet/scramjet flowpath. Steady-state simulations were performed at splitter cowl positions of 0deg, -2deg, -4deg, and -5.7deg, at which the turbine flowpath was closed half way. The simulations satisfied one objective of providing a greater understanding of the flow during inlet mode transition. Comparisons of the simulation results with wind-tunnel test data addressed another objective of assessing the applicability of the simulation methods for simulating inlet mode transition. The simulations showed that inlet mode transition could occur in a stable manner and that accurate modeling of the interactions among the shock waves, boundary layers, and porous bleed regions was critical for evaluating the inlet static and total pressures, bleed flow rates, and bleed plenum pressures. The simulations compared well with some of the wind-tunnel data, but uncertainties in both the windtunnel data and simulations prevented a formal evaluation of the accuracy of the simulation methods.

  1. Sometimes Getting There Is Half the Fun

    ERIC Educational Resources Information Center

    Hanlon, Kerri

    2008-01-01

    Vacations for exceptional families require flexibility, persistence, a sense of humor, and a view of the world as the glass being half full. In this article, the author shares her family's summer vacation experience. If "getting there is half the fun," the author's family has had more than their share of fun times. She has learned the…

  2. Discrete monotron oscillator having one-half wavelength coaxial resonator with one-quarter wavelength gap spacing

    DOEpatents

    Carlsten, B.E.; Haynes, W.B.

    1998-02-03

    A discrete monotron oscillator for use in a high power microwave device is formed with a microwave oscillator having a half-wavelength resonant coaxial microwave cavity operating in fundamental TEM mode for microwave oscillation with an inner conductor defining a drift tube for propagating an electron beam and an outer conductor coaxial with the inner conductor. The inner conductor defines a modulating gap and an extraction gap downstream of the modulating gap. The modulating gap and the extraction gap connect the coaxial microwave cavity with the drift tube so that energy for the microwave oscillation is extracted from the electron beam at the extraction gap and modulates the electron beam at the modulating gap. For high power operation, an annular electron beam is used. 8 figs.

  3. Discrete monotron oscillator having one-half wavelength coaxial resonator with one-quarter wavelength gap spacing

    DOEpatents

    Carlsten, Bruce E.; Haynes, William B.

    1998-01-01

    A discrete monotron oscillator for use in a high power microwave device is formed with a microwave oscillator having a half-wavelength resonant coaxial microwave cavity operating in fundamental TEM mode for microwave oscillation with an inner conductor defining a drift tube for propagating an electron beam and an outer conductor coaxial with the inner conductor. The inner conductor defines a modulating gap and an extraction gap downstream of the modulating gap. The modulating gap and the extraction gap connect the coaxial microwave cavity with the drift tube so that energy for the microwave oscillation is extracted from the electron beam at the extraction gap and modulates the electron beam at the modulating gap. For high power operation, an annular electron beam is used.

  4. Historically hottest summers projected to be the norm for more than half of the world’s population within 20 years

    NASA Astrophysics Data System (ADS)

    Mueller, Brigitte; Zhang, Xuebin; Zwiers, Francis W.

    2016-04-01

    We project that within the next two decades, half of the world’s population will regularly (every second summer on average) experience regional summer mean temperatures that exceed those of the historically hottest summer, even under the moderate RCP4.5 emissions pathway. This frequency threshold for hot temperatures over land, which have adverse effects on human health, society and economy, might be broached in little more than a decade under the RCP8.5 emissions pathway. These hot summer frequency projections are based on adjusted RCP4.5 and 8.5 temperature projections, where the adjustments are performed with scaling factors determined by regularized optimal fingerprinting analyzes that compare historical model simulations with observations over the period 1950-2012. A temperature reconstruction technique is then used to simulate a multitude of possible past and future temperature evolutions, from which the probability of a hot summer is determined for each region, with a hot summer being defined as the historically warmest summer on record in that region. Probabilities with and without external forcing show that hot summers are now about ten times more likely (fraction of attributable risk 0.9) in many regions of the world than they would have been in the absence of past greenhouse gas increases. The adjusted future projections suggest that the Mediterranean, Sahara, large parts of Asia and the Western US and Canada will be among the first regions for which hot summers will become the norm (i.e. occur on average every other year), and that this will occur within the next 1-2 decades.

  5. Mode evolution in polarization maintain few mode fibers and applications in mode-division-multiplexing systems

    NASA Astrophysics Data System (ADS)

    Li, Yan; Zeng, Xinglin; Mo, Qi; Li, Wei; Liu, Zhijian; Wu, Jian

    2016-10-01

    In few-mode polarization-maintaining-fiber (FM-PMF), the effective-index splitting exists not only between orthogonally polarization state but also between degenerated modes within a high-order mode group. Hence besides the polarization state evolution, the mode patterns in each LP set are need to be analyzed. In this letter, the completed firstorder mode (LP11 mode) evolution in PM-FMF is analyzed and represented by analogous Jones vector and Poincarésphere respectively. Furthermore, with Jones matrix analysis, the modal dynamics in FM-PMFs is conveniently analyzed. The conclusions are used to propose a PM-FMF based LP11 mode rotator and an PM-FMF based OAM generator. Both simulation and experiments are conducted to investigate performance of the two devices.

  6. Dual-cavity mode converter for a fundamental mode output in an over-moded relativistic backward-wave oscillator

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

    Li, Jiawei; Huang, Wenhua; Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an 710024

    2015-03-16

    A dual-cavity TM{sub 02}–TM{sub 01} mode converter is designed for a dual-mode operation over-moded relativistic backward-wave oscillator. With the converter, the fundamental mode output is achieved. Particle-in-cell simulation shows that the efficiency of beam-wave conversion was over 46% and a pureTM{sub 01} mode output was obtained. Effects of end reflection provided by the mode converter were studied. Adequate TM{sub 01} mode feedback provided by the converter enhances conversion efficiency. The distance between the mode converter and extraction cavity critically affect the generation of microwaves depending on the reflection phase of TM{sub 01} mode feedback.

  7. Two Populations of Sunspots: Differential Rotation

    NASA Astrophysics Data System (ADS)

    Nagovitsyn, Yu. A.; Pevtsov, A. A.; Osipova, A. A.

    2018-03-01

    To investigate the differential rotation of sunspot groups using the Greenwich data, we propose an approach based on a statistical analysis of the histograms of particular longitudinal velocities in different latitude intervals. The general statistical velocity distributions for all such intervals are shown to be described by two rather than one normal distribution, so that two fundamental rotation modes exist simultaneously: fast and slow. The differentiality of rotation for the modes is the same: the coefficient at sin2 in Faye's law is 2.87-2.88 deg/day, while the equatorial rotation rates differ significantly, 0.27 deg/day. On the other hand, an analysis of the longitudinal velocities for the previously revealed two differing populations of sunspot groups has shown that small short-lived groups (SSGs) are associated with the fast rotation mode, while large long-lived groups (LLGs) are associated with both fast and slow modes. The results obtained not only suggest a real physical difference between the two populations of sunspots but also give new empirical data for the development of a dynamo theory, in particular, for the theory of a spatially distributed dynamo.

  8. Half-life of 51Mn

    NASA Astrophysics Data System (ADS)

    Graves, Stephen A.; Ellison, Paul A.; Valdovinos, Hector F.; Barnhart, Todd E.; Nickles, Robert J.; Engle, Jonathan W.

    2017-07-01

    The half-life of 51Mn was measured by serial gamma spectrometry of the 511-keV annihilation photon following decay by β+ emission. Data were collected every 100 seconds for 100,000-230,000 seconds within each measurement (n =4 ). The 511-keV incidence rate was calculated from the 511-keV spectral peak area and count duration, corrected for detector dead time and radioactive decay. Least-squares regression analysis was used to determine the half-life of 51Mn while accounting for the presence of background contaminants, notably 55Co. The result was 45.59 ±0.07 min, which is the highest precision measurement to date and disagrees with the current Nuclear Data Sheets value by over 6 σ .

  9. Single-mode fiber laser based on core-cladding mode conversion.

    PubMed

    Suzuki, Shigeru; Schülzgen, Axel; Peyghambarian, N

    2008-02-15

    A single-mode fiber laser based on an intracavity core-cladding mode conversion is demonstrated. The fiber laser consists of an Er-doped active fiber and two fiber Bragg gratings. One Bragg grating is a core-cladding mode converter, and the other Bragg grating is a narrowband high reflector that selects the lasing wavelength. Coupling a single core mode and a single cladding mode by the grating mode converter, the laser operates as a hybrid single-mode laser. This approach for designing a laser cavity provides a much larger mode area than conventional large-mode-area step-index fibers.

  10. Scaling Fiber Lasers to Large Mode Area: An Investigation of Passive Mode-Locking Using a Multi-Mode Fiber

    PubMed Central

    Ding, Edwin; Lefrancois, Simon; Kutz, Jose Nathan; Wise, Frank W.

    2011-01-01

    The mode-locking of dissipative soliton fiber lasers using large mode area fiber supporting multiple transverse modes is studied experimentally and theoretically. The averaged mode-locking dynamics in a multi-mode fiber are studied using a distributed model. The co-propagation of multiple transverse modes is governed by a system of coupled Ginzburg–Landau equations. Simulations show that stable and robust mode-locked pulses can be produced. However, the mode-locking can be destabilized by excessive higher-order mode content. Experiments using large core step-index fiber, photonic crystal fiber, and chirally-coupled core fiber show that mode-locking can be significantly disturbed in the presence of higher-order modes, resulting in lower maximum single-pulse energies. In practice, spatial mode content must be carefully controlled to achieve full pulse energy scaling. This paper demonstrates that mode-locking performance is very sensitive to the presence of multiple waveguide modes when compared to systems such as amplifiers and continuous-wave lasers. PMID:21731106

  11. Scaling Fiber Lasers to Large Mode Area: An Investigation of Passive Mode-Locking Using a Multi-Mode Fiber.

    PubMed

    Ding, Edwin; Lefrancois, Simon; Kutz, Jose Nathan; Wise, Frank W

    2011-01-01

    The mode-locking of dissipative soliton fiber lasers using large mode area fiber supporting multiple transverse modes is studied experimentally and theoretically. The averaged mode-locking dynamics in a multi-mode fiber are studied using a distributed model. The co-propagation of multiple transverse modes is governed by a system of coupled Ginzburg-Landau equations. Simulations show that stable and robust mode-locked pulses can be produced. However, the mode-locking can be destabilized by excessive higher-order mode content. Experiments using large core step-index fiber, photonic crystal fiber, and chirally-coupled core fiber show that mode-locking can be significantly disturbed in the presence of higher-order modes, resulting in lower maximum single-pulse energies. In practice, spatial mode content must be carefully controlled to achieve full pulse energy scaling. This paper demonstrates that mode-locking performance is very sensitive to the presence of multiple waveguide modes when compared to systems such as amplifiers and continuous-wave lasers.

  12. Density and spin modes in imbalanced normal Fermi gases from collisionless to hydrodynamic regime

    NASA Astrophysics Data System (ADS)

    Narushima, Masato; Watabe, Shohei; Nikuni, Tetsuro

    2018-03-01

    We study the mass- and population-imbalance effect on density (in-phase) and spin (out-of-phase) collective modes in a two-component normal Fermi gas. By calculating the eigenmodes of the linearized Boltzmann equation as well as the density/spin dynamic structure factor, we show that mass- and population-imbalance effects offer a variety of collective mode crossover behaviors from collisionless to hydrodynamic regimes. The mass-imbalance effect shifts the crossover regime to the higher-temperature, and a significant peak of the spin dynamic structure factor emerges only in the collisionless regime. This is in contrast to the case of mass- and population-balanced normal Fermi gases, where the spin dynamic response is always absent. Although the population-imbalance effect does not shift the crossover regime, the spin dynamic structure factor survives both in the collisionless and hydrodynamic regimes.

  13. Improved half-metallic gap of zincblende half-metal superlattices with the Tran-Blaha modified Becke-Johnson density functional

    NASA Astrophysics Data System (ADS)

    Guo, San-Dong

    2016-08-01

    Binary transition-metal pnictides and chalcogenides half-metallic ferromagnetic materials with zincblende structure, being compatible with current semiconductor technology, can be used to make high-performance spintronic devices. Here, we investigate electronic structures and magnetic properties of composite structure ((CrX)2 /(YX)2 (X=As, Sb; Se, Te and Y=Ga; Zn) superlattices) of zincblende half-metallic ferromagnetism and semiconductor by using Tran and Blaha's modified Becke and Johnson (mBJ) exchange potential. Calculated results show that they all are half-metallic ferromagnets with both generalized gradient approximation (GGA) and mBJ, and the total magnetic moment per formula unit follows a Slater-Pauling-like "rule of 8". The key half-metallic gaps by using mBJ are enhanced with respect to GGA results, which is because mBJ makes the occupied minority-spin p-bands move toward lower energy, but toward higher energy for empty minority-spin Cr-d bands. When the spin-orbit coupling (SOC) is included, the spin polarization deviates from 100%, and a most reduced polarization of 98.3% for (CrSb)2 /(GaSb)2, which indicates that SOC has small effects, of the order of 1%, in the considered four kinds of superlattice.

  14. Dual mode operation, highly selective nanohole array-based plasmonic colour filters

    NASA Astrophysics Data System (ADS)

    Fouladi Mahani, Fatemeh; Mokhtari, Arash; Mehran, Mahdiyeh

    2017-09-01

    Taking advantage of nanostructured metal films as plasmonic colour filters (PCFs) has been evolved remarkably as an alternative to the conventional technologies of chemical colour filtering. However, most of the proposed PCFs depict a poor colour purity focusing on generating either the additive or subtractive colours. In this paper, we present dual mode operation PCFs employing an opaque aluminium film patterned with sub-wavelength holes. Subtractive colours like cyan, magenta, and yellow are the results of reflection mode of these filters yielding optical efficiencies as high as 70%-80% and full width at half maximum of the stop-bands up to 40-50 nm. The colour selectivity of the transmission mode for the additive colours is also significant due to their enhanced performance through the utilization of a relatively thick aluminium film in contact with a modified dielectric environment. These filters provide a simple design with one-step lithography in addition to compatibility with the conventional CMOS processes. Moreover, they are polarization insensitive due to their symmetric geometry. A complete palette of pure subtractive and additive colours has been realized with potential applications, such as multispectral imaging, CMOS image sensors, displays, and colour printing.

  15. Dual mode operation, highly selective nanohole array-based plasmonic colour filters.

    PubMed

    Mahani, Fatemeh Fouladi; Mokhtari, Arash; Mehran, Mahdiyeh

    2017-09-20

    Taking advantage of nanostructured metal films as plasmonic colour filters (PCFs) has been evolved remarkably as an alternative to the conventional technologies of chemical colour filtering. However, most of the proposed PCFs depict a poor colour purity focusing on generating either the additive or subtractive colours. In this paper, we present dual mode operation PCFs employing an opaque aluminium film patterned with sub-wavelength holes. Subtractive colours like cyan, magenta, and yellow are the results of reflection mode of these filters yielding optical efficiencies as high as 70%-80% and full width at half maximum of the stop-bands up to 40-50 nm. The colour selectivity of the transmission mode for the additive colours is also significant due to their enhanced performance through the utilization of a relatively thick aluminium film in contact with a modified dielectric environment. These filters provide a simple design with one-step lithography in addition to compatibility with the conventional CMOS processes. Moreover, they are polarization insensitive due to their symmetric geometry. A complete palette of pure subtractive and additive colours has been realized with potential applications, such as multispectral imaging, CMOS image sensors, displays, and colour printing.

  16. Early Results from the First Year of Observations by the Atacama B-mode Search (ABS)

    NASA Astrophysics Data System (ADS)

    Simon, Sara M.; ABS Collaboration

    2013-06-01

    The Atacama B-mode Search (ABS) instrument, which began observation in February of 2012, is a crossed-Dragone telescope located at an elevation of 5100 m in the Atacama Desert in Chile. The primary scientific goal of ABS is to measure the B-mode polarization spectrum of the Cosmic Microwave Background (CMB) from multipole moments of about l=50 to l=500, a range that includes the primordial B-mode peak. Unlike most current polarization experiments, ABS features a cryogenic telescope and a warm half-wave plate used to modulate the polarization of the incoming light. The ABS focal plane array consists of 240 pixels designed for observation at 150 GHz by the TRUCE collaboration. Each pixel has its own individual, single-moded feedhorn and contains two transition-edge sensor (TES) bolometers sensitive to orthogonal polarizations. The detectors are read out using time domain multiplexing so that the thermal loading of the readout electronics does not heat the focal plane. I will present early results from the first year of ABS data.

  17. ARSENIC MODE OF ACTION AND DEVELOPING A BBDR MODEL

    EPA Science Inventory

    The current USEPA cancer risk assessment for inorganic arsenic is based on a linear extrapolation of the epidemiological data from exposed populations in Taiwan. However, proposed key events in the mode of action (MoA) for arsenic-induced cancer (which may include altered DNA me...

  18. DecouplingModes: Passive modes amplitudes

    NASA Astrophysics Data System (ADS)

    Shaw, J. Richard; Lewis, Antony

    2018-01-01

    DecouplingModes calculates the amplitude of the passive modes, which requires solving the Einstein equations on superhorizon scales sourced by the anisotropic stress from the magnetic fields (prior to neutrino decoupling), and the magnetic and neutrino stress (after decoupling). The code is available as a Mathematica notebook.

  19. Low threshold L-band mode-locked ultrafast fiber laser assisted by microfiber-based carbon nanotube saturable absorber

    NASA Astrophysics Data System (ADS)

    Lau, K. Y.; Ng, E. K.; Abu Bakar, M. H.; Abas, A. F.; Alresheedi, M. T.; Yusoff, Z.; Mahdi, M. A.

    2018-04-01

    We demonstrate a passively mode-locked erbium-doped fiber laser in L-band wavelength region with low mode-locking threshold employing a 1425 nm pump wavelength. The mode-locking regime is generated by microfiber-based saturable absorber using carbon nanotube-polymer composite in a ring cavity. This carbon nanotube saturable absorber shows saturation intensity of 9 MW/cm2. In this work, mode-locking laser threshold is observed at 36.4 mW pump power. At the maximum pump power of 107.6 mW, we obtain pulse duration at full-width half-maximum point of 490 fs and time bandwidth product of 0.33, which corresponds to 3-dB spectral bandwidth of 5.8 nm. The pulse repetition rate remains constant throughout the experiment at 5.8 MHz due to fixed cavity length of 35.5 m. Average output power and pulse energy of 10.8 mW and 1.92 nJ are attained respectively through a 30% laser output extracted from the mode-locked cavity. This work highlights the feasibility of attaining a low threshold mode-locked laser source to be employed as seed laser in L-band wavelength region.

  20. The role of insect dispersal and migration in population processes

    NASA Technical Reports Server (NTRS)

    Rabb, R. L.; Stinner, R. E.

    1979-01-01

    Movement functions in the population dynamics of insects are discussed. Modes of movement, movement from a population view, and population patterns are described and predicted. A wide-area of spatial and temporal patterns are presented.

  1. Half-lives of 214Pb and 214Bi.

    PubMed

    Martz, D E; Langner, G H; Johnson, P R

    1991-10-01

    New measurements on chemically separated samples of 214Bi have yielded a mean half-life value of 19.71 +/- 0.02 min, where the error quoted is twice the standard deviation of the mean based on 23 decay runs. This result provides strong support for the historic 19.72 +/- 0.04 min half-life value and essentially excludes the 19.9-min value, both reported in previous studies. New measurements of the decay rate of 222Rn progeny activity initially in radioactive equilibrium have yielded a value of 26.89 +/- 0.03 min for the half-life of 214Pb, where the error quoted is twice the standard deviation of the mean based on 12 decay runs. This value is 0.1 min longer than the currently accepted 214Pb half-value of 26.8 min.

  2. Online Farsi digit recognition using their upper half structure

    NASA Astrophysics Data System (ADS)

    Ghods, Vahid; Sohrabi, Mohammad Karim

    2015-03-01

    In this paper, we investigated the efficiency of upper half Farsi numerical digit structure. In other words, half of data (upper half of the digit shapes) was exploited for the recognition of Farsi numerical digits. This method can be used for both offline and online recognition. Half of data is more effective in speed process, data transfer and in this application accuracy. Hidden Markov model (HMM) was used to classify online Farsi digits. Evaluation was performed by TMU dataset. This dataset contains more than 1200 samples of online handwritten Farsi digits. The proposed method yielded more accuracy in recognition rate.

  3. In quantum direct communication an undetectable eavesdropper can always tell Ψ from Φ Bell states in the message mode

    NASA Astrophysics Data System (ADS)

    Pavičić, Mladen

    2013-04-01

    We show that in any quantum direct communication protocol that is based on Ψ and Φ Bell states, an eavesdropper can always tell Ψ from Φ states without altering the transmission in any way in the message mode. This renders all protocols that make use of only one Ψ state and one Φ state completely insecure in the message mode. All four-Bell-state protocols require a revision and this might be of importance for new implementations of entanglement-based cryptographic protocols. The detection rate of an eavesdropper is 25% per control transmission, i.e., a half of the rate in the two-state (ping-pong) protocol. An eavesdropper can detect control probes with certainty in the standard control transmission without a photon in the Alice-to-Bob's travel mode and with near certainty in a transmission with a fake photon in the travel mode. Resending of measured control photons via the travel mode would make an eavesdropper completely invisible.

  4. The Mode of Professional Teaching Practice of FCS Teacher-Leaders and Non-Teacher-Leaders.

    ERIC Educational Resources Information Center

    Fox, Candace K.; Laster, Janet F.

    A study was conducted to determine which of the following modes of professional practice is the dominant mode used by Ohio family and consumer science (FCS) teachers when implementing a refined critical science based curriculum: technical-rational; reflective-ethical; and process-oriented. The target population consisted of 1,013 secondary…

  5. Maven Observations of Electron-Induced Whistler Mode Waves in the Martian Magnetosphere

    NASA Technical Reports Server (NTRS)

    Harada, Y.; Andersson, L.; Fowler, C. M.; Mitchell, D. L.; Halekas, J. S.; Mazelle, C.; Espley, J.; DiBraccio, G. A.; McFadden, J. P.; Brian, D. A.; hide

    2016-01-01

    We report on narrowband electromagnetic waves at frequencies between the local electron cyclotron and lower hybrid frequencies observed by the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft in the Martian induced magnetosphere. The peaked electric field wave spectra below the electron cyclotron frequency were first observed by Phobos-2 in the Martian magnetosphere, but the lack of magnetic field wave data prevented definitive identification of the wave mode and their generation mechanisms remain unclear. Analysis of electric and magnetic field wave spectra obtained by MAVEN demonstrates that the observed narrowband waves have properties consistent with the whistler mode. Linear growth rates computed from the measured electron velocity distributions suggest that these whistler mode waves can be generated by cyclotron resonance with anisotropic electrons. Large electron anisotropy in the Martian magnetosphere is caused by absorption of parallel electrons by the collisional atmosphere. The narrowband whistler mode waves and anisotropic electrons are observed on both open and closed field lines and have similar spatial distributions in MSO and planetary coordinates. Some of the waves on closed field lines exhibit complex frequency-time structures such as discrete elements of rising tones and two bands above and below half the electron cyclotron frequency. These MAVEN observations indicate that whistler mode waves driven by anisotropic electrons, which are commonly observed in intrinsic magnetospheres and at unmagnetized airless bodies, are also present at Mars. The wave-induced electron precipitation into the Martian atmosphere should be evaluated in future studies.

  6. Engineering half-Heusler thermoelectric materials using Zintl chemistry

    NASA Astrophysics Data System (ADS)

    Zeier, Wolfgang G.; Schmitt, Jennifer; Hautier, Geoffroy; Aydemir, Umut; Gibbs, Zachary M.; Felser, Claudia; Snyder, G. Jeffrey

    2016-06-01

    Half-Heusler compounds based on XNiSn and XCoSb (X = Ti, Zr or Hf) have rapidly become important thermoelectric materials for converting waste heat into electricity. In this Review, we provide an overview on the electronic properties of half-Heusler compounds in an attempt to understand their basic structural chemistry and physical properties, and to guide their further development. Half-Heusler compounds can exhibit semiconducting transport behaviour even though they are described as ‘intermetallic’ compounds. Therefore, it is most useful to consider these systems as rigid-band semiconductors within the framework of Zintl (or valence-precise) compounds. These considerations aid our understanding of their properties, such as the bandgap and low hole mobility because of interstitial Ni defects in XNiSn. Understanding the structural and bonding characteristics, including the presence of defects, will help to develop different strategies to improve and design better half-Heusler thermoelectric materials.

  7. The Causal Effect of Survey Mode on Students' Evaluations of Teaching: Empirical Evidence from Three Field Experiments

    ERIC Educational Resources Information Center

    Treischl, Edgar; Wolbring, Tobias

    2017-01-01

    In recent years many universities switched from paper- to online-based student evaluation of teaching (SET) without knowing the consequences for data quality. Based on a series of three consecutive field experiments--a split-half design, twin courses, and pre-post-measurements--this paper examines the effects of survey mode on SET. First, all…

  8. Plexciton Dirac points and topological modes

    DOE PAGES

    Yuen-Zhou, Joel; Saikin, Semion K.; Zhu, Tony; ...

    2016-06-09

    Plexcitons are polaritonic modes that result from the strong coupling between excitons and plasmons. Here, we consider plexcitons emerging from the interaction of excitons in an organic molecular layer with surface plasmons in a metallic film. We predict the emergence of Dirac cones in the two-dimensional band-structure of plexcitons due to the inherent alignment of the excitonic transitions in the organic layer. An external magnetic field opens a gap between the Dirac cones if the plexciton system is interfaced with a magneto-optical layer. The resulting energy gap becomes populated with topologically protected one-way modes, which travel at the interface ofmore » this plexcitonic system. Furthermore, our theoretical proposal suggests that plexcitons are a convenient and simple platform for the exploration of exotic phases of matter and for the control of energy flow at the nanoscale.« less

  9. A variable-mode stator consequent pole memory machine

    NASA Astrophysics Data System (ADS)

    Yang, Hui; Lyu, Shukang; Lin, Heyun; Zhu, Z. Q.

    2018-05-01

    In this paper, a variable-mode concept is proposed for the speed range extension of a stator-consequent-pole memory machine (SCPMM). An integrated permanent magnet (PM) and electrically excited control scheme is utilized to simplify the flux-weakening control instead of relatively complicated continuous PM magnetization control. Due to the nature of memory machine, the magnetization state of low coercive force (LCF) magnets can be easily changed by applying either a positive or negative current pulse. Therefore, the number of PM poles may be changed to satisfy the specific performance requirement under different speed ranges, i.e. the machine with all PM poles can offer high torque output while that with half PM poles provides wide constant power range. In addition, the SCPMM with non-magnetized PMs can be considered as a dual-three phase electrically excited reluctance machine, which can be fed by an open-winding based dual inverters that provide direct current (DC) bias excitation to further extend the speed range. The effectiveness of the proposed variable-mode operation for extending its operating region and improving the system reliability is verified by both finite element analysis (FEA) and experiments.

  10. The half-life of 218Po.

    PubMed

    Martz, D E; Harris, R T; Langner, G H

    1989-07-01

    Direct observation of the 218Po alpha-peak decay with a microcomputer-controlled alpha-spectrometer yielded a mean half-life value of 3.040 +/- 0.008 min, where the error quoted represents twice the standard deviation of the means from 38 separate decay measurements. The 1912 and 1924 218Po half-life measurements, which provided the 3.05-min value listed in nuclear tables for the past 60 y, are critically reviewed. Two more recent experiments, which yielded longer values of 3.11 min (Van Hise et al. 1982) and 3.093 min (Potapov and Soloshenkov 1986), are also discussed.

  11. LibHalfSpace: A C++ object-oriented library to study deformation and stress in elastic half-spaces

    NASA Astrophysics Data System (ADS)

    Ferrari, Claudio; Bonafede, Maurizio; Belardinelli, Maria Elina

    2016-11-01

    The study of deformation processes in elastic half-spaces is widely employed for many purposes (e.g. didactic, scientific investigation of real processes, inversion of geodetic data, etc.). We present a coherent programming interface containing a set of tools designed to make easier and faster the study of processes in an elastic half-space. LibHalfSpace is presented in the form of an object-oriented library. A set of well known and frequently used source models (Mogi source, penny shaped horizontal crack, inflating spheroid, Okada rectangular dislocation, etc.) are implemented to describe the potential usage and the versatility of the library. The common interface given to library tools enables us to switch easily among the effects produced by different deformation sources that can be monitored at the free surface. Furthermore, the library also offers an interface which simplifies the creation of new source models exploiting the features of object-oriented programming (OOP). These source models can be built as distributions of rectangular boundary elements. In order to better explain how new models can be deployed some examples are included in the library.

  12. Comparison of symmetric and asymmetric double quantum well extended-cavity diode lasers for broadband passive mode-locking at 780  nm.

    PubMed

    Christopher, Heike; Kovalchuk, Evgeny V; Wenzel, Hans; Bugge, Frank; Weyers, Markus; Wicht, Andreas; Peters, Achim; Tränkle, Günther

    2017-07-01

    We present a compact, mode-locked diode laser system designed to emit a frequency comb in the wavelength range around 780 nm. We compare the mode-locking performance of symmetric and asymmetric double quantum well ridge-waveguide diode laser chips in an extended-cavity diode laser configuration. By reverse biasing a short section of the diode laser chip, passive mode-locking at 3.4 GHz is achieved. Employing an asymmetric double quantum well allows for generation of a mode-locked optical spectrum spanning more than 15 nm (full width at -20  dB) while the symmetric double quantum well device only provides a bandwidth of ∼2.7  nm (full width at -20  dB). Analysis of the RF noise characteristics of the pulse repetition rate shows an RF linewidth of about 7 kHz (full width at half-maximum) and of at most 530 Hz (full width at half-maximum) for the asymmetric and symmetric double quantum well devices, respectively. Investigation of the frequency noise power spectral density at the pulse repetition rate shows a white noise floor of approximately 2100  Hz 2 /Hz and of at most 170  Hz 2 /Hz for the diode laser employing the asymmetric and symmetric double quantum well structures, respectively. The pulse width is less than 10 ps for both devices.

  13. Historically hottest summers projected to be the norm for more than half of the world’s population within 20 years

    DOE PAGES

    Mueller, Brigitte; Zhang, Xuebin; Zwiers, Francis W.

    2016-04-07

    We project that within the next two decades, half of the world's population will regularly (every second summer on average) experience regional summer mean temperatures that exceed those of the historically hottest summer, even under the moderate RCP4.5 emissions pathway. This frequency threshold for hot temperatures over land, which have adverse effects on human health, society and economy, might be broached in little more than a decade under the RCP8.5 emissions pathway. These hot summer frequency projections are based on adjusted RCP4.5 and 8.5 temperature projections, where the adjustments are performed with scaling factors determined by regularized optimal fingerprinting analyzesmore » that compare historical model simulations with observations over the period 1950-2012. A temperature reconstruction technique is then used to simulate a multitude of possible past and future temperature evolutions, from which the probability of a hot summer is determined for each region, with a hot summer being defined as the historically warmest summer on record in that region. Probabilities with and without external forcing show that hot summers are now about ten times more likely (fraction of attributable risk 0.9) in many regions of the world than they would have been in the absence of past greenhouse gas increases. In conclusion, the adjusted future projections suggest that the Mediterranean, Sahara, large parts of Asia and the Western US and Canada will be among the first regions for which hot summers will become the norm (i.e. occur on average every other year), and that this will occur within the next 1-2 decades.« less

  14. The mutation-drift balance in spatially structured populations.

    PubMed

    Schneider, David M; Martins, Ayana B; de Aguiar, Marcus A M

    2016-08-07

    In finite populations the action of neutral mutations is balanced by genetic drift, leading to a stationary distribution of alleles that displays a transition between two different behaviors. For small mutation rates most individuals will carry the same allele at equilibrium, whereas for high mutation rates of the alleles will be randomly distributed with frequencies close to one half for a biallelic gene. For well-mixed haploid populations the mutation threshold is μc=1/2N, where N is the population size. In this paper we study how spatial structure affects this mutation threshold. Specifically, we study the stationary allele distribution for populations placed on regular networks where connected nodes represent potential mating partners. We show that the mutation threshold is sensitive to spatial structure only if the number of potential mates is very small. In this limit, the mutation threshold decreases substantially, increasing the diversity of the population at considerably low mutation rates. Defining kc as the degree of the network for which the mutation threshold drops to half of its value in well-mixed populations we show that kc grows slowly as a function of the population size, following a power law. Our calculations and simulations are based on the Moran model and on a mapping between the Moran model with mutations and the voter model with opinion makers. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. PEPlife: A Repository of the Half-life of Peptides

    NASA Astrophysics Data System (ADS)

    Mathur, Deepika; Prakash, Satya; Anand, Priya; Kaur, Harpreet; Agrawal, Piyush; Mehta, Ayesha; Kumar, Rajesh; Singh, Sandeep; Raghava, Gajendra P. S.

    2016-11-01

    Short half-life is one of the key challenges in the field of therapeutic peptides. Various studies have reported enhancement in the stability of peptides using methods like chemical modifications, D-amino acid substitution, cyclization, replacement of labile aminos acids, etc. In order to study this scattered data, there is a pressing need for a repository dedicated to the half-life of peptides. To fill this lacuna, we have developed PEPlife (http://crdd.osdd.net/raghava/peplife), a manually curated resource of experimentally determined half-life of peptides. PEPlife contains 2229 entries covering 1193 unique peptides. Each entry provides detailed information of the peptide, like its name, sequence, half-life, modifications, the experimental assay for determining half-life, biological nature and activity of the peptide. We also maintain SMILES and structures of peptides. We have incorporated web-based modules to offer user-friendly data searching and browsing in the database. PEPlife integrates numerous tools to perform various types of analysis such as BLAST, Smith-Waterman algorithm, GGSEARCH, Jalview and MUSTANG. PEPlife would augment the understanding of different factors that affect the half-life of peptides like modifications, sequence, length, route of delivery of the peptide, etc. We anticipate that PEPlife will be useful for the researchers working in the area of peptide-based therapeutics.

  16. Predictive Variables of Half-Marathon Performance for Male Runners.

    PubMed

    Gómez-Molina, Josué; Ogueta-Alday, Ana; Camara, Jesus; Stickley, Christoper; Rodríguez-Marroyo, José A; García-López, Juan

    2017-06-01

    The aims of this study were to establish and validate various predictive equations of half-marathon performance. Seventy-eight half-marathon male runners participated in two different phases. Phase 1 (n = 48) was used to establish the equations for estimating half-marathon performance, and Phase 2 (n = 30) to validate these equations. Apart from half-marathon performance, training-related and anthropometric variables were recorded, and an incremental test on a treadmill was performed, in which physiological (VO 2max , speed at the anaerobic threshold, peak speed) and biomechanical variables (contact and flight times, step length and step rate) were registered. In Phase 1, half-marathon performance could be predicted to 90.3% by variables related to training and anthropometry (Equation 1), 94.9% by physiological variables (Equation 2), 93.7% by biomechanical parameters (Equation 3) and 96.2% by a general equation (Equation 4). Using these equations, in Phase 2 the predicted time was significantly correlated with performance (r = 0.78, 0.92, 0.90 and 0.95, respectively). The proposed equations and their validation showed a high prediction of half-marathon performance in long distance male runners, considered from different approaches. Furthermore, they improved the prediction performance of previous studies, which makes them a highly practical application in the field of training and performance.

  17. Flapping modes of three filaments placed side by side in a free stream

    NASA Astrophysics Data System (ADS)

    Tian, Fang-Bao; Luo, Haoxiang; Zhu, Luoding; Lu, Xi-Yun

    2010-11-01

    Flexible filaments flapping in a surrounding flow are useful models for understanding the flow-induced vibration and mimicking the schooling behavior of fish. In the present work, the coupled modes of three identical filaments in a side-by- side arrangement are studied using the linear stability analysis and also an immersed boundary--lattice Boltzmann method for low Reynolds numbers (Re on order of 100). The numerical simulations show that the system dynamics exhibits several patterns that depend on the spacing between the filaments. Among these patterns, three can be predicted by the linear analysis and have been reported before. These modes are: (1) the three filaments all flap in phase; (2) the two outer filaments are out of phase while the middle one is stable; (3) the two outer filaments are in phase while the middle one is out of phase. The simulations also identified two additional modes: (1) the outer two filaments are out of phase while the middle one flaps at a frequency reduced by half; (2) the outer two filaments are out of phase while the middle one flaps at a slightly different frequency. In addition to the vibratory modes, the drag force and the flapping amplitude are also computed, and the implication of the result will be discussed.

  18. Analysis and Design of Bridgeless Switched Mode Power Supply for Computers

    NASA Astrophysics Data System (ADS)

    Singh, S.; Bhuvaneswari, G.; Singh, B.

    2014-09-01

    Switched mode power supplies (SMPSs) used in computers need multiple isolated and stiffly regulated output dc voltages with different current ratings. These isolated multiple output dc voltages are obtained by using a multi-winding high frequency transformer (HFT). A half-bridge dc-dc converter is used here for obtaining different isolated and well regulated dc voltages. In the front end, non-isolated Single Ended Primary Inductance Converters (SEPICs) are added to improve the power quality in terms of low input current harmonics and high power factor (PF). Two non-isolated SEPICs are connected in a way to completely eliminate the need of single-phase diode-bridge rectifier at the front end. Output dc voltages at both the non-isolated and isolated stages are controlled and regulated separately for power quality improvement. A voltage mode control approach is used in the non-isolated SEPIC stage for simple and effective control whereas average current control is used in the second isolated stage.

  19. Computational investigation of half-Heusler compounds for spintronics applications

    NASA Astrophysics Data System (ADS)

    Ma, Jianhua; Hegde, Vinay I.; Munira, Kamaram; Xie, Yunkun; Keshavarz, Sahar; Mildebrath, David T.; Wolverton, C.; Ghosh, Avik W.; Butler, W. H.

    2017-01-01

    We present first-principles density functional calculations of the electronic structure, magnetism, and structural stability of 378 XYZ half-Heusler compounds (with X = Cr, Mn, Fe, Co, Ni, Ru, Rh; Y = Ti, V, Cr, Mn, Fe, Ni; Z = Al, Ga, In, Si, Ge, Sn, P, As, Sb). We find that a "Slater-Pauling gap" in the density of states (i.e., a gap or pseudogap after nine states in the three atom primitive cell) in at least one spin channel is a common feature in half-Heusler compounds. We find that the presence of such a gap at the Fermi energy in one or both spin channels contributes significantly to the stability of a half-Heusler compound. We calculate the formation energy of each compound and systematically investigate its stability against all other phases in the open quantum materials database (OQMD). We represent the thermodynamic phase stability of each compound as its distance from the convex hull of stable phases in the respective chemical space and show that the hull distance of a compound is a good measure of the likelihood of its experimental synthesis. We find low formation energies and mostly correspondingly low hull distances for compounds with X = Co, Rh, or Ni, Y = Ti or V, and Z = P, As, Sb, or Si. We identify 26 18-electron semiconductors, 45 half-metals, and 34 near half-metals with negative formation energy that follow the Slater-Pauling rule of three electrons per atom. Our calculations predict several new, as-yet unknown, thermodynamically stable phases, which merit further experimental exploration—RuVAs, CoVGe, FeVAs in the half-Heusler structure, and NiScAs, RuVP, RhTiP in the orthorhombic MgSrSi-type structure. Further, two interesting zero-moment half-metals, CrMnAs and MnCrAs, are calculated to have negative formation energy. In addition, our calculations predict a number of hitherto unreported semiconducting (e.g., CoVSn and RhVGe), half-metallic (e.g., RhVSb), and near half-metallic (e.g., CoFeSb and CoVP) half-Heusler compounds to lie close to

  20. Half-Lives of 101Rh and 108m Ag

    NASA Astrophysics Data System (ADS)

    Norman, Eric; Browne, Edgardo; Shugart, Howard

    2014-09-01

    Half-lives of short-lived nuclei can easily be measured by direct counting techniques, whereas those of long-lived naturally-occurring nuclei are usually determined by specific activity measurements. However, half-lives in the range of 1 - 1,000,000 years are notoriously difficult to determine. For example, published values for the half-life of 101Rh range from 3.0 +/- 0.4 years to 10 +/- 1 years, and for 108m Ag published values range from 127 +/- 21 years to 438 +/- 9 years. In order to resolve the issues of what the half-lives of these isotopes actually are, we set up two separate long-term gamma-ray counting experiments. Gamma-ray data were collected in time bins using high-purity Ge detectors and ORTEC PC-based data acquisition systems. We counted in this manner for a period of approximately 5 years for 101Rh and 3 years for 108mAg. In this talk we will describe the details of these experiments and will present the final results for the half-lives of 101Rh and 108mAg determined from these measurements. Half-lives of short-lived nuclei can easily be measured by direct counting techniques, whereas those of long-lived naturally-occurring nuclei are usually determined by specific activity measurements. However, half-lives in the range of 1 - 1,000,000 years are notoriously difficult to determine. For example, published values for the half-life of 101Rh range from 3.0 +/- 0.4 years to 10 +/- 1 years, and for 108m Ag published values range from 127 +/- 21 years to 438 +/- 9 years. In order to resolve the issues of what the half-lives of these isotopes actually are, we set up two separate long-term gamma-ray counting experiments. Gamma-ray data were collected in time bins using high-purity Ge detectors and ORTEC PC-based data acquisition systems. We counted in this manner for a period of approximately 5 years for 101Rh and 3 years for 108mAg. In this talk we will describe the details of these experiments and will present the final results for the half-lives of 101Rh

  1. [Study on the biological characteristic of Blastocystis hominis: morphology, mode of reproduction and the relation to bacteria].

    PubMed

    Qiao, Ji-ying; Zhang, Xu; Wei, Zhi-chao; Yang, Jun-hua; Li, Ya-qing; Zhang, Rong

    2006-11-01

    To observe the reproductive modes of Blastocystis hominis and study the relation between this protozoa and bacteria. Using the Iodine and Haematoxylin staining, the morphology of B. h from patients and RPMI 1640 medium were observed. The B. h positive mucous diarrheal specimens were cultured and identified any possible known pathogenic intestinal bacteria. B. h and colibacillus were co-cultured to observe the interaction between them. Four modes of reproduction for B. h were confirmed: binary fission, endodyogeny, multiple fission and budding. The fact that there was no other intestinal pathogens in half of the B. h positive specimens suggested B. h may cause disease independently. B. h and colibacillus were restrained each other. B. h reproduces in at least four modes. B. h could be a pathogen and its pathogenesis may be related to micro-ecological changes.

  2. Discovering modes of action for therapeutic compounds using a genome-wide screen of yeast heterozygotes.

    PubMed

    Lum, Pek Yee; Armour, Christopher D; Stepaniants, Sergey B; Cavet, Guy; Wolf, Maria K; Butler, J Scott; Hinshaw, Jerald C; Garnier, Philippe; Prestwich, Glenn D; Leonardson, Amy; Garrett-Engele, Philip; Rush, Christopher M; Bard, Martin; Schimmack, Greg; Phillips, John W; Roberts, Christopher J; Shoemaker, Daniel D

    2004-01-09

    Modern medicine faces the challenge of developing safer and more effective therapies to treat human diseases. Many drugs currently in use were discovered without knowledge of their underlying molecular mechanisms. Understanding their biological targets and modes of action will be essential to design improved second-generation compounds. Here, we describe the use of a genome-wide pool of tagged heterozygotes to assess the cellular effects of 78 compounds in Saccharomyces cerevisiae. Specifically, lanosterol synthase in the sterol biosynthetic pathway was identified as a target of the antianginal drug molsidomine, which may explain its cholesterol-lowering effects. Further, the rRNA processing exosome was identified as a potential target of the cell growth inhibitor 5-fluorouracil. This genome-wide screen validated previously characterized targets or helped identify potentially new modes of action for over half of the compounds tested, providing proof of this principle for analyzing the modes of action of clinically relevant compounds.

  3. Near elimination of ventricular pacing in SafeR mode compared to DDD modes: a randomized study of 422 patients.

    PubMed

    Davy, Jean-Marc; Hoffmann, Ellen; Frey, Axel; Jocham, Kurt; Rossi, Stefano; Dupuis, Jean-Marc; Frabetti, Lorenzo; Ducloux, Pascale; Prades, Emmanuel; Jauvert, Gaël

    2012-04-01

    SafeR performance versus DDD/automatic mode conversion (DDD/AMC) and DDD with a 250-ms atrioventricular (AV) delay (DDD/LD) modes was assessed toward ventricular pacing (Vp) reduction. After a 1-month run-in phase, recipients of dual-chamber pacemakers without persistent AV block and persistent atrial fibrillation (AF) were randomly assigned to SafeR, DDD/AMC, or DDD/LD in a 1:1:1 design. The main endpoint was the percentage of Vp (%Vp) at 2 months and 1 year after randomization, ascertained from device memories. Secondary endpoints include %Vp at 1 year according to pacing indication and 1-year AF incidence based on automatic mode switch device stored episodes. Among 422 randomized patients (73.2±10.6 years, 50% men, sinus node dysfunction 47.4%, paroxysmal AV block 30.3%, bradycardia-tachycardia syndrome 21.8%), 141 were assigned to SafeR versus 146 to DDD/AMC and 135 to DDD/LD modes. Mean %Vp at 2 months was 3.4±12.6% in SafeR versus 33.6±34.7% and 14.0±26.0% in DDD/AMC and DDD/LD modes, respectively (P<0.0001 for both). At 1 year, mean %Vp in SafeR was 4.5±15.3% versus 37.9±34.4% and 16.7±28.0% in DDD/AMC and DDD/LD modes, respectively (P<0.0001 for both). The proportion of patients in whom Vp was completely eliminated was significantly higher in SafeR (69%) versus DDD/AMC (15%) and DDD/LD (45%) modes (P<0.0001 for both), regardless of pacing indication. The absolute risk of developing permanent AF or of remaining in AF for >30% of the time was 5.4% lower in SafeR than in the DDD pacing group (ns). In this selected patient population, SafeR markedly suppressed unnecessary Vp compared with DDD modes. ©2012, The Authors. Journal compilation ©2012 Wiley Periodicals, Inc.

  4. Lommel modes

    NASA Astrophysics Data System (ADS)

    Kovalev, Alexey A.; Kotlyar, Victor V.

    2015-03-01

    We study a non-paraxial family of nondiffracting laser beams whose complex amplitude is proportional to an n-th order Lommel function of two variables. These beams are referred to as Lommel modes. Explicit analytical relations for the angular spectrum of plane waves and orbital angular momentum of the Lommel beams have been derived. The even (n=2p) and odd (n=2p+1) Lommel modes are mutually orthogonal, as are the Lommel modes characterized by different projections of the wave vector on the optical axis. At a definite parameter, the Lommel modes change to conventional Bessel beams. Asymmetry of the Lommel modes depends on a complex parameter с, with its modulus in the polar notation defining the intensity pattern in the beam‧s cross-section and the argument defining the angle of rotation of the intensity pattern about the optical axis. If the parameter с is real or purely imaginary, the transverse intensity component of the Lommel modes is specularly symmetric about the Cartesian coordinate axes. Besides, with the modulus of the с parameter increasing from 0 to 1, the orbital angular momentum of the Lommel modes increases from a finite value proportional to the topological charge n to infinity. The orbital angular momentum of the Lommel modes undergoes continuous variations, in contrast to its discrete changes in the Bessel modes.

  5. Functional neuroimaging with default mode network regions distinguishes PTSD from TBI in a military veteran population.

    PubMed

    Raji, Cyrus A; Willeumier, Kristen; Taylor, Derek; Tarzwell, Robert; Newberg, Andrew; Henderson, Theodore A; Amen, Daniel G

    2015-09-01

    PTSD and TBI are two common conditions in veteran populations that can be difficult to distinguish clinically. The default mode network (DMN) is abnormal in a multitude of neurological and psychiatric disorders. We hypothesize that brain perfusion SPECT can be applied to diagnostically separate PTSD from TBI reliably in a veteran cohort using DMN regions. A group of 196 veterans (36 with PTSD, 115 with TBI, 45 with PTSD/TBI) were selected from a large multi-site population cohort of individuals with psychiatric disease. Inclusion criteria were peacetime or wartime veterans regardless of branch of service and included those for whom the traumatic brain injury was not service related. SPECT imaging was performed on this group both at rest and during a concentration task. These measures, as well as the baseline-concentration difference, were then inputted from DMN regions into separate binary logistic regression models controlling for age, gender, race, clinic site, co-morbid psychiatric diseases, TBI severity, whether or not the TBI was service related, and branch of armed service. Predicted probabilities were then inputted into a receiver operating characteristic analysis to compute sensitivity, specificity, and accuracy. Compared to PSTD, persons with TBI were older, male, and had higher rates of bipolar and major depressive disorder (p < 0.05). Baseline quantitative regions with SPECT separated PTSD from TBI in the veterans with 92 % sensitivity, 85 % specificity, and 94 % accuracy. With concentration scans, there was 85 % sensitivity, 83 % specificity and 89 % accuracy. Baseline-concentration (the difference metric between the two scans) scans were 85 % sensitivity, 80 % specificity, and 87 % accuracy. In separating TBI from PTSD/TBI visual readings of baseline scans had 85 % sensitivity, 81 % specificity, and 83 % accuracy. Concentration scans had 80 % sensitivity, 65 % specificity, and 79 % accuracy. Baseline-concentration scans had 82

  6. Phase locking of multi-helicity neoclassical tearing modes in tokamak plasmas

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

    Fitzpatrick, Richard

    2015-04-15

    The attractive “hybrid” tokamak scenario combines comparatively high q{sub 95} operation with improved confinement compared with the conventional H{sub 98,y2} scaling law. Somewhat unusually, hybrid discharges often exhibit multiple neoclassical tearing modes (NTMs) possessing different mode numbers. The various NTMs are eventually observed to phase lock to one another, giving rise to a significant flattening, or even an inversion, of the core toroidal plasma rotation profile. This behavior is highly undesirable because the loss of core plasma rotation is known to have a deleterious effect on plasma stability. This paper presents a simple, single-fluid, cylindrical model of the phase lockingmore » of two NTMs with different poloidal and toroidal mode numbers in a tokamak plasma. Such locking takes place via a combination of nonlinear three-wave coupling and conventional toroidal coupling. In accordance with experimental observations, the model predicts that there is a bifurcation to a phase-locked state when the frequency mismatch between the modes is reduced to one half of its original value. In further accordance, the phase-locked state is characterized by the permanent alignment of one of the X-points of NTM island chains on the outboard mid-plane of the plasma, and a modified toroidal angular velocity profile, interior to the outermost coupled rational surface, which is such that the core rotation is flattened, or even inverted.« less

  7. Adiabatically tapered microstructured mode converter for selective excitation of the fundamental mode in a few mode fiber.

    PubMed

    Taher, Aymen Belhadj; Di Bin, Philippe; Bahloul, Faouzi; Tartaret-Josnière, Etienne; Jossent, Mathieu; Février, Sébastien; Attia, Rabah

    2016-01-25

    We propose a new technique to selectively excite the fundamental mode in a few mode fiber (FMF). This method of excitation is made from a single mode fiber (SMF) which is inserted facing the FMF into an air-silica microstructured cane before the assembly is adiabatically tapered. We study theoretically and numerically this method by calculating the effective indices of the propagated modes, their amplitudes along the taper and the adiabaticity criteria, showing the ability to achieve an excellent selective excitation of the fundamental mode in the FMF with negligible loss. We experimentally demonstrate that the proposed solution provides a successful mode conversion and allows an almost excellent fundamental mode excitation in the FMF (representing 99.8% of the total power).

  8. Experimental Study of Second-Mode Instabilities on a 7-Degree Cone at Mach 6

    NASA Technical Reports Server (NTRS)

    Rufer, Shann J.; Berridge, Dennis C.

    2011-01-01

    Experiments have been carried out in the NASA Langley Research Center 20-Inch Mach 6 Air Tunnel to measure the second-mode boundary-layer instability on a 7deg half-angle cone using high-frequency pressure sensors. Data were obtained with both blunt and sharp nosetips installed on the cone. The second-mode wave amplitudes were observed to saturate and then begin to decrease in the Langley tunnels, indicating wave breakdown. Pressure fluctuation measurements and thermocouple data indicated the location of transition along the cone at the different conditions tested. Comparisons between the power density spectra obtained during the current test and previous data from the Langley 15-Inch Mach 6 High Temperature Tunnel and the Boeing/AFOSR Mach 6 Quiet tunnel illustrate the effect of tunnel noise on instability growth and transition.

  9. Assessment of the Maximal Split-Half Coefficient to Estimate Reliability

    ERIC Educational Resources Information Center

    Thompson, Barry L.; Green, Samuel B.; Yang, Yanyun

    2010-01-01

    The maximal split-half coefficient is computed by calculating all possible split-half reliability estimates for a scale and then choosing the maximal value as the reliability estimate. Osburn compared the maximal split-half coefficient with 10 other internal consistency estimates of reliability and concluded that it yielded the most consistently…

  10. Investigation on the oscillation modes in a thermoacoustic Stirling prime mover: mode stability and mode transition

    NASA Astrophysics Data System (ADS)

    Yu, Z. B.; Li, Q.; Chen, X.; Guo, F. Z.; Xie, X. J.; Wu, J. H.

    2003-12-01

    The purpose of this paper is to investigate the stability of oscillation modes in a thermoacoustic Stirling prime mover, which is a combination of looped tube and resonator. Two modes, with oscillation frequencies of 76 and 528 Hz, have been observed, stabilities of which are widely different. The stability of the high frequency mode (HFM) is affected by low frequency mode (LFM) strongly. Once the LFM is excited when the HFM is present, the HFM will be gradually slaved and suppressed by the LFM. The details of the transition from HFM to LFM have been described. The two stability curves of the two modes have been measured. Mean pressure Pm is an important control parameter influencing the mode stability in the tested system.

  11. Half-State Readout In Vertical-Bloch-Line Memory

    NASA Technical Reports Server (NTRS)

    Katti, Romney R.; Wu, Jiin-Chuan; Stadler, Henry L.

    1994-01-01

    Potentially narrow margins of chirality-based chopping of magnetic stripes avoided. Half-state readout is experimental method of readout in Vertical-Bloch-Line (VBL) memory. Based on differential deflections of magnetic stripe domains in which data bits stored. To give meaning to explanation of half-state readout, see "Vertical-Bloch-Line Memory" (NPO-18467).

  12. Active vs. spectator modes in nonadiabatic photodissociation dynamics of the hydroxymethyl radical via the 22A(3s) Rydberg state

    NASA Astrophysics Data System (ADS)

    Xie, Changjian; Guo, Hua

    2018-01-01

    The choice of the active degrees of freedom (DOFs) is a pivotal issue in a reduced-dimensional model of quantum dynamics when a full-dimensional one is not feasible. Here, several five-dimensional (5D) models are used to investigate the nonadiabatic photodissociation dynamics of the hydroxymethyl (CH2OH) radical, which possesses nine internal DOFs, in its lowest absorption band. A normal-mode based scheme is used to identify the active and spectator modes, and its predictions are confirmed by 5D quantum dynamical calculations. Our results underscore the important role of the CO stretching mode in the photodissociation dynamics of CH2OH, originating from the photo-induced promotion of an electron from the half-occupied π*CO antibonding orbital to a carbon Rydberg orbital.

  13. A tunable comb filter using single-mode/multimode/polarization-maintaining-fiber-based Sagnac fiber loop

    NASA Astrophysics Data System (ADS)

    Ruan, Juan; Zhang, Wei-Gang; Zhang, Hao; Geng, Peng-Cheng; Bai, Zhi-Yong

    2013-06-01

    A novel tunable comb filter composed of a single-mode/multimode/polarization-maintaining-fiber-based Sagnac fiber loop is proposed and experimentally demonstrated. The filter tunability is achieved by rotating the polarization controller. The spectral shift is dependent on rotation direction and the position of the polarization controller. In addition, the adjustable range achieved by rotating the half-wave-plate polarization controller is twice higher than that of the quarter-wave-plate one.

  14. Multiple secondary islands formation in nonlinear evolution of double tearing mode simulations

    NASA Astrophysics Data System (ADS)

    Guo, W.; Ma, J.; Yu, Z.

    2017-03-01

    A new numerical code solving the conservative perturbed resistive magnetohydrodynamic (MHD) model is developed. Numerical tests of the ideal Kelvin-Helmholtz instability and the resistive double tearing mode (DTM) show its capability in solving linear and nonlinear MHD instabilities. The nonlinear DTM evolution in 2D geometry is numerically investigated with low guiding field B z 0 , short half-distance y 0 between the equilibrium current sheets, and small resistivity η. The interaction of islands on the two initial current sheets may generate an unstable flow driven current sheet with a high length-to-thickness aspect ratio (α), and multiple secondary islands can form. In general, the length-to-thickness aspect ratio α and the number of secondary islands increase with decreasing guide field B z 0 , decreasing half-distance y 0 , and increasing Lundquist number of the flow driven current sheet S L although the dependence may be non-monotonic. The reconnection rate dependence on S L , B z 0 , and y 0 is also investigated.

  15. Tempo and mode of genomic mutations unveil human evolutionary history.

    PubMed

    Hara, Yuichiro

    2015-01-01

    Mutations that have occurred in human genomes provide insight into various aspects of evolutionary history such as speciation events and degrees of natural selection. Comparing genome sequences between human and great apes or among humans is a feasible approach for inferring human evolutionary history. Recent advances in high-throughput or so-called 'next-generation' DNA sequencing technologies have enabled the sequencing of thousands of individual human genomes, as well as a variety of reference genomes of hominids, many of which are publicly available. These sequence data can help to unveil the detailed demographic history of the lineage leading to humans as well as the explosion of modern human population size in the last several thousand years. In addition, high-throughput sequencing illustrates the tempo and mode of de novo mutations, which are producing human genetic variation at this moment. Pedigree-based human genome sequencing has shown that mutation rates vary significantly across the human genome. These studies have also provided an improved timescale of human evolution, because the mutation rate estimated from pedigree analysis is half that estimated from traditional analyses based on molecular phylogeny. Because of the dramatic reduction in sequencing cost, sequencing on-demand samples designed for specific studies is now also becoming popular. To produce data of sufficient quality to meet the requirements of the study, it is necessary to set an explicit sequencing plan that includes the choice of sample collection methods, sequencing platforms, and number of sequence reads.

  16. Half-lives of 132La and 135La

    NASA Astrophysics Data System (ADS)

    Abel, E. P.; Clause, H. K.; Fonslet, J.; Nickles, R. J.; Severin, G. W.

    2018-03-01

    The half-lives of 135La and 132La were determined via serial gamma spectroscopy, and the half-life of 135La was further determined by a high-precision ionization-chamber measurement. The results are 18.91(2) hr for 135La and 4.59(4) hr for 132La compared with the previously compiled values of 19.5(2) hr and 4.8(2) hr, respectively. These lanthanum isotopes comprise a medically interesting system with positron emitter 132La and Auger-electron emitter 135La forming a theranostic pair for internal diagnostics and therapeutics. The precise half-lives are necessary for proper evaluation of their value in medicine and for a more representative tabulation of nuclear data.

  17. PLC-based LP₁₁ mode rotator for mode-division multiplexing transmission.

    PubMed

    Saitoh, Kunimasa; Uematsu, Takui; Hanzawa, Nobutomo; Ishizaka, Yuhei; Masumoto, Kohei; Sakamoto, Taiji; Matsui, Takashi; Tsujikawa, Kyozo; Yamamoto, Fumihiko

    2014-08-11

    A PLC-based LP11 mode rotator is proposed. The proposed mode rotator is composed of a waveguide with a trench that provides asymmetry of the waveguide. Numerical simulations show that converting LP11a (LP11b) mode to LP11b (LP11a) mode can be achieved with high conversion efficiency (more than 90%) and little polarization dependence over a wide wavelength range from 1450 nm to 1650 nm. In addition, we fabricate the proposed LP11 mode rotator using silica-based PLC. It is confirmed that the fabricated mode rotator can convert LP11a mode to LP11b mode over a wide wavelength range.

  18. Competition and evolution of dielectric waveguide mode and plasmonic waveguide mode

    NASA Astrophysics Data System (ADS)

    Yuan, Sheng-Nan; Fang, Yun-Tuan

    2017-10-01

    In order to study the coupling and evolution law of the waveguide mode and two plasmonic surface modes, we construct a line defect waveguide based on hexagonal honeycomb plasmonic photonic crystal. Through adjusting the radius of the edge dielectric rods, the competition and evolution behaviors occur between dielectric waveguide mode and plasmonic waveguide mode. There are three status: only plasmonic waveguide modes occur for rA < 0.09a; only dielectric waveguide modes occur for rA > 0.25a; two kinds of modes coexist for 0.09a < rA < 0.25a. The plasmonic waveguide mode has advantages in achieving slow light.

  19. HALO--a Java framework for precise transcript half-life determination.

    PubMed

    Friedel, Caroline C; Kaufmann, Stefanie; Dölken, Lars; Zimmer, Ralf

    2010-05-01

    Recent improvements in experimental technologies now allow measurements of de novo transcription and/or RNA decay at whole transcriptome level and determination of precise transcript half-lives. Such transcript half-lives provide important insights into the regulation of biological processes and the relative contributions of RNA decay and de novo transcription to differential gene expression. In this article, we present HALO (Half-life Organizer), the first software for the precise determination of transcript half-lives from measurements of RNA de novo transcription or decay determined with microarrays or RNA-seq. In addition, methods for quality control, filtering and normalization are supplied. HALO provides a graphical user interface, command-line tools and a well-documented Java application programming interface (API). Thus, it can be used both by biologists to determine transcript half-lives fast and reliably with the provided user interfaces as well as software developers integrating transcript half-life analysis into other gene expression profiling pipelines. Source code, executables and documentation are available at http://www.bio.ifi.lmu.de/software/halo.

  20. [Population and development].

    PubMed

    Castanon Romo, R; Sandoval Navarrete, J

    1996-01-01

    This broad survey of the debate concerning the relationship between population growth and economic development discusses the history and current status of world population growth, summarizes several influential theoretical positions on the topic, and proposes that redefinition of women's social role is indispensable if worldwide control of population growth is to be achieved. The introductory section discusses the acceleration of population growth in the second half of the 20th century and the increasing concentration of growth in the poor and developing countries. The positions of those who see in population control a means of promoting economic development and political stability are contrasted to the positions of those who believe that a large and growing population is the key to achieving economic and political progress. The international community, facing great uncertainty about the size, distribution, and well-being of the future world population, is increasingly concerned about the effect of growing numbers on the environment and natural resources. The second section summarizes the works of Malthus, Julian Simon, and the Club of Rome, and analyzes the propositions of demographic transition theory. The conclusion notes that despite uncertainty about the future of world population, development, and health, most of the poorest countries have become aware of the desirability of slowing population growth. A broad redefinition of the social role of women will inevitably accompany the worldwide demographic transition.

  1. Higher Education and Disability: Past and Future of Underrepresented Populations

    ERIC Educational Resources Information Center

    Leake, David W.; Stodden, Robert A.

    2014-01-01

    Over the past half century higher education in the United States has been challenged to develop and implement policies and practices that effectively promote the access, retention, and graduation of diverse underrepresented populations. One of these populations is comprised of individuals with disabilities, whose equal access to higher education…

  2. Sex- and age-related differences in half-marathon performance and competitiveness in the world's largest half-marathon - the GöteborgsVarvet.

    PubMed

    Knechtle, B; Nikolaidis, P T

    2018-01-01

    In road runners, the age-related performance decline has been well investigated for marathoners, but little is known for half-marathoners. We analysed data from 138,616 runners (48,148 women and 90,469 men) competing between 2014 and 2016 in GöteborgsVarvet, the world's largest half-marathon. The men-to-women ratio in participants increased with age, the fastest race times were observed in age groups ˂35 and 35-39 years in women and in age group 35-39 years in men, the main effect of sex and the sex × age group interaction on race time were trivial, and the competitiveness was denser in men and in the younger age groups. In summary, in half-marathon running in the largest half-marathon in the world, the GöteborgsVarvet, women achieved the fastest race time at an earlier age compared to men where the fastest race times were observed in women in age groups ˂35 and 35-39 years and in men in age group 35-39 years.

  3. Influence of driving frequency on discharge modes in a dielectric-barrier discharge with multiple current pulses

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

    Jiang, Weiman; Tang, Jie; Wang, Yishan

    2013-07-15

    A one-dimensional self-consistent fluid model was employed to investigate the effect of the driving frequency on the discharge modes in atmospheric-pressure argon discharge with multiple current pulses. The discharge mode was discussed in detail not only at current peaks but also between two adjacent peaks. The simulation results show that different transitions between the Townsend and glow modes during the discharge take place with the driving frequency increased. A complicated transition from the Townsend mode, through glow, Townsend, and glow, and finally back to the Townsend one is found in the discharge with the driving frequency of 8 kHz. Theremore » is a tendency of transition from the Townsend to glow mode for the discharge both at the current peaks and troughs with the increasing frequency. The discharge in the half period can all along operate in the glow mode with the driving frequency high enough. This is resulted from the preservation of more electrons in the gas gap and acquisition of more electron energy from the swiftly varying electric field with the increase in driving frequency. Comparison of the spatial and temporal evolutions of the electron density at different driving frequencies indicates that the increment of the driving frequency allows the plasma chemistry to be enhanced. This electrical characteristic is important for the applications, such as surface treatment and biomedical sterilization.« less

  4. Green’s functions for a volume source in an elastic half-space

    PubMed Central

    Zabolotskaya, Evgenia A.; Ilinskii, Yurii A.; Hay, Todd A.; Hamilton, Mark F.

    2012-01-01

    Green’s functions are derived for elastic waves generated by a volume source in a homogeneous isotropic half-space. The context is sources at shallow burial depths, for which surface (Rayleigh) and bulk waves, both longitudinal and transverse, can be generated with comparable magnitudes. Two approaches are followed. First, the Green’s function is expanded with respect to eigenmodes that correspond to Rayleigh waves. While bulk waves are thus ignored, this approximation is valid on the surface far from the source, where the Rayleigh wave modes dominate. The second approach employs an angular spectrum that accounts for the bulk waves and yields a solution that may be separated into two terms. One is associated with bulk waves, the other with Rayleigh waves. The latter is proved to be identical to the Green’s function obtained following the first approach. The Green’s function obtained via angular spectrum decomposition is analyzed numerically in the time domain for different burial depths and distances to the receiver, and for parameters relevant to seismo-acoustic detection of land mines and other buried objects. PMID:22423682

  5. Static and dynamic half-life and lifetime molecular turnover of enzymes.

    PubMed

    Miyawaki, Osato; Kanazawa, Tsukasa; Maruyama, Chika; Dozen, Michiko

    2017-01-01

    The static half-life of an enzyme is the half-life of a free enzyme not working without substrate and the dynamic half-life is that of an active enzyme working with plenty amount of substrate. These two half-lives were measured and compared for glucoamylase (GA) and β-galactosidase (BG). The dynamic half-life was much longer than the static half-life by one to three orders of magnitude for both enzymes. For BG, the half-life of the enzyme physically entrapped in a membrane reactor was also measured. In this case also, the half-life of BG in the membrane reactor was much longer than the free enzyme without substrate. These results suggest the large difference in stabilities between the free enzyme and the enzyme-substrate complex. This may be related to the natural enzyme metabolism. According to the difference in half-life, the lifetime molecular turnover (LMT), which is the number of product molecules produced by a single molecule of enzyme until it loses its activity completely, was much higher by one to four orders of magnitude for the active enzyme than the free enzyme. The concept of LMT, proposed here, will be important in bioreactor operations with or without immobilization. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  6. Displacement field for an edge dislocation in a layered half-space

    USGS Publications Warehouse

    Savage, J.C.

    1998-01-01

    The displacement field for an edge dislocation in an Earth model consisting of a layer welded to a half-space of different material is found in the form of a Fourier integral following the method given by Weeks et al. [1968]. There are four elementary solutions to be considered: the dislocation is either in the half-space or the layer and the Burgers vector is either parallel or perpendicular to the layer. A general two-dimensional solution for a dip-slip faulting or dike injection (arbitrary dip) can be constructed from a superposition of these elementary solutions. Surface deformations have been calculated for an edge dislocation located at the interface with Burgers vector inclined 0??, 30??, 60??, and 90?? to the interface for the case where the rigidity of the layer is half of that of the half-space and the Poisson ratios are the same. Those displacement fields have been compared to the displacement fields generated by similarly situated edge dislocations in a uniform half-space. The surface displacement field produced by the edge dislocation in the layered half-space is very similar to that produced by an edge dislocation at a different depth in a uniform half-space. In general, a low-modulus (high-modulus) layer causes the half-space equivalent dislocation to appear shallower (deeper) than the actual dislocation in the layered half-space.

  7. AAPM/RSNA physics tutorial for residents. Topics in US: B-mode US: basic concepts and new technology.

    PubMed

    Hangiandreou, Nicholas J

    2003-01-01

    Ultrasonography (US) has been used in medical imaging for over half a century. Current US scanners are based largely on the same basic principles used in the initial devices for human imaging. Modern equipment uses a pulse-echo approach with a brightness-mode (B-mode) display. Fundamental aspects of the B-mode imaging process include basic ultrasound physics, interactions of ultrasound with tissue, ultrasound pulse formation, scanning the ultrasound beam, and echo detection and signal processing. Recent technical innovations that have been developed to improve the performance of modern US equipment include the following: tissue harmonic imaging, spatial compound imaging, extended field of view imaging, coded pulse excitation, electronic section focusing, three-dimensional and four-dimensional imaging, and the general trend toward equipment miniaturization. US is a relatively inexpensive, portable, safe, and real-time modality, all of which make it one of the most widely used imaging modalities in medicine. Although B-mode US is sometimes referred to as a mature technology, this modality continues to experience a significant evolution in capability with even more exciting developments on the horizon. Copyright RSNA, 2003

  8. Single-Mode VCSELs

    NASA Astrophysics Data System (ADS)

    Larsson, Anders; Gustavsson, Johan S.

    The only active transverse mode in a truly single-mode VCSEL is the fundamental mode with a near Gaussian field distribution. A single-mode VCSEL produces a light beam of higher spectral purity, higher degree of coherence and lower divergence than a multimode VCSEL and the beam can be more precisely shaped and focused to a smaller spot. Such beam properties are required in many applications. In this chapter, after discussing applications of single-mode VCSELs, we introduce the basics of fields and modes in VCSELs and review designs implemented for single-mode emission from VCSELs in different materials and at different wavelengths. This includes VCSELs that are inherently single-mode as well as inherently multimode VCSELs where higher-order modes are suppressed by mode selective gain or loss. In each case we present the current state-of-the-art and discuss pros and cons. At the end, a specific example with experimental results is provided and, as a summary, the most promising designs based on current technologies are identified.

  9. Half-Unit Insulin Pens: Disease Management in Patients With Diabetes Who Are Sensitive to Insulin.

    PubMed

    Klonoff, David C; Nayberg, Irina; Stauder, Udo; Oualali, Hamid; Domenger, Catherine

    2017-05-01

    Insulin pens represent a significant technological advancement in diabetes management. While the vast majority have been designed with 1U-dosing increments, improved accuracy and precision facilitated by half-unit increments may be particularly significant in specific patients who are sensitive to insulin. These include patients with low insulin requirements and in those requiring more precise dose adjustments, such as the pediatric patient population. This review summarized functional characteristics of insulin half-unit pens (HUPs) and their effect on user experience. The literature search was restricted to articles published in English between January 1, 2000, and January 1, 2015. A total of 17 publications met the set criteria and were included in the review. Overall, studies outlined characteristics for 4 insulin HUPs. Based on their functionality, the pens were generally similar and all met the ISO 11608-1 criteria for accuracy. However, some had specific advantageous features in terms of size, weight, design, dialing torque, and injection force. Although limited, the currently available user preference studies in children and adolescents with diabetes and their carers suggest that the selection of an HUP is likely to be influenced by a combination of factors such as these, in addition to the prescribed insulin and dosing regimen. Insulin HUPs are likely to be a key diabetes management tool for patients who are sensitive to insulin; specific pen features may further advance diabetes management in these populations.

  10. Single mode, broad-waveguide ARROW-type semiconductor diode lasers

    NASA Astrophysics Data System (ADS)

    Al-Muhanna, Abdulrahman Ali

    A broad transverse waveguide (low confinement) concept is used to achieve a record-high spatially incoherent cw output power of 11W for InGaAs active devices (λ = 0.97 μm) from 100μm wide-stripe and 2mm-long devices with low internal loss, α1 = 1cm-1, and high characteristic temperatures, T0 = 210K, and T1 = 1800K. A detailed above-threshold analysis reveals that reduction in gain spatial hole burning (GSHB) is possible in ARROW-type structures by using a low transverse confinement factor; consequently, a wider ARROW-core can be utilized. By incorporating both a broad-waveguide concept as well as an asymmetric structure in the transverse direction, and an ARROW-type structure in the lateral direction, a novel single-spatial mode diode laser with improved performance is obtained. Devices with low transverse confinement factor (Γ ~ 1%) and a core-region width of 7.8 μm achieved 510mW single-spatial mode pulsed output power (λ = 0.946 μm) with a full- width at half-maximum (FWHM) of the lateral far-field pattern of 4.7°.

  11. Validation of Mode-S Meteorological Routine Air Report aircraft observations

    NASA Astrophysics Data System (ADS)

    Strajnar, B.

    2012-12-01

    The success of mesoscale data assimilation depends on the availability of three-dimensional observations with high spatial and temporal resolution. This paper describes an example of such observations, available through Mode-S air traffic control system composed of ground radar and transponders on board the aircraft. The meteorological information is provided by interrogation of a dedicated meteorological data register, called Meteorological Routine Air Report (MRAR). MRAR provides direct measurements of temperature and wind, but is only returned by a small fraction of aircraft. The quality of Mode-S MRAR data, collected at the Ljubljana Airport, Slovenia, is assessed by its comparison with AMDAR and high-resolution radiosonde data sets, which enable high- and low-level validation, respectively. The need for temporal smoothing of raw Mode-S MRAR data is also studied. The standard deviation of differences between smoothed Mode-S MRAR and AMDAR is 0.35°C for temperature, 0.8 m/s for wind speed and below 10 degrees for wind direction. The differences with respect to radiosondes are larger, with standard deviations of approximately 1.7°C, 3 m/s and 25 degrees for temperature, wind speed and wind direction, respectively. It is concluded that both wind and temperature observations from Mode-S MRAR are accurate and therefore potentially very useful for data assimilation in numerical weather prediction models.

  12. A reconstruction of sexual modes throughout animal evolution.

    PubMed

    Sasson, Daniel A; Ryan, Joseph F

    2017-12-06

    Although most extant animals have separate sexes, simultaneous hermaphrodites can be found in lineages throughout the animal kingdom. However, the sexual modes of key ancestral nodes including the last common ancestor (LCA) of all animals remain unclear. Without these data, it is difficult to infer the reproductive-state transitions that occurred early in animal evolution, and thus a broad understanding of the evolution of animal reproduction remains elusive. In this study, we use a composite phylogeny from four previously published studies, two alternative topologies (ctenophores or sponges as sister to the rest of animals), and multiple phylogenetic approaches to conduct the most extensive analysis to date of the evolution of animal sexual modes. Our analyses clarify the sexual mode of many ancestral animal nodes and allow for sound inferences of modal transitions that have occurred in animal history. Our results also indicate that the transition from separate sexes to hermaphroditism has been more common in animal history than the reverse. These results provide the most complete view of the evolution of animal sexual modes to date and provide a framework for future inquiries into the correlation of these transitions with genes, behaviors, and physiology. These results also suggest that mutations promoting hermaphroditism have historically been more likely to invade gonochoristic populations than vice versa.

  13. Measurement of the 20F half-life

    NASA Astrophysics Data System (ADS)

    Hughes, M.; George, E. A.; Naviliat-Cuncic, O.; Voytas, P. A.; Chandavar, S.; Gade, A.; Huyan, X.; Liddick, S. N.; Minamisono, K.; Paulauskas, S. V.; Weisshaar, D.

    2018-05-01

    The half-life of the 20F ground state was measured using a radioactive beam implanted in a plastic scintillator and recording β γ coincidences together with four CsI(Na) detectors. The result, T1 /2=11.0011 (69) stat(30) sys s, is at variance by 17 combined standard deviations with the two most precise results. The present value revives the poor consistency of results for this half-life and calls for a new measurement, with a technique having different sources of systematic effects, to clarify the discrepancy.

  14. Half wavelength dipole antennas over stratified media

    NASA Technical Reports Server (NTRS)

    Latorraca, G. A.

    1972-01-01

    Theoretical solutions of the fields induced by half-wavelength, horizontal, electric field dipoles (HEDS) are determined based on studies of infinitesimal, horizontal, electric field dipoles over low loss plane-stratified media. To determine these solutions, an approximation to the current distribution of a half-wavelength HED is derived and experimentally verified. Traverse and antenna measurements obtained on the Athabasca Glacier in the summer of 1971 are related to the characteristics of the transmitting antenna design, and the measurement techniques and field equipment used in the glacier trials are described and evaluated.

  15. Long-term effective population size dynamics of an intensively monitored vertebrate population

    PubMed Central

    Mueller, A-K; Chakarov, N; Krüger, O; Hoffman, J I

    2016-01-01

    Long-term genetic data from intensively monitored natural populations are important for understanding how effective population sizes (Ne) can vary over time. We therefore genotyped 1622 common buzzard (Buteo buteo) chicks sampled over 12 consecutive years (2002–2013 inclusive) at 15 microsatellite loci. This data set allowed us to both compare single-sample with temporal approaches and explore temporal patterns in the effective number of parents that produced each cohort in relation to the observed population dynamics. We found reasonable consistency between linkage disequilibrium-based single-sample and temporal estimators, particularly during the latter half of the study, but no clear relationship between annual Ne estimates () and census sizes. We also documented a 14-fold increase in between 2008 and 2011, a period during which the census size doubled, probably reflecting a combination of higher adult survival and immigration from further afield. Our study thus reveals appreciable temporal heterogeneity in the effective population size of a natural vertebrate population, confirms the need for long-term studies and cautions against drawing conclusions from a single sample. PMID:27553455

  16. Properties of a novel linear sulfur response mode in a multiple flame photometric detector.

    PubMed

    Clark, Adrian G; Thurbide, Kevin B

    2014-01-24

    A new linear sulfur response mode was established in the multiple flame photometric detector (mFPD) by monitoring HSO* emission in the red spectral region above 600nm. Optimal conditions for this mode were found by using a 750nm interference filter and oxygen flows to the worker flames of this device that were about 10mL/min larger than those used for monitoring quadratic S2* emission. By employing these parameters, this mode provided a linear response over about 4 orders of magnitude, with a detection limit near 5.8×10(-11)gS/s and a selectivity of sulfur over carbon of about 3.5×10(3). Specifically, the minimum detectable masses for 10 different sulfur analytes investigated ranged from 0.4 to 3.6ng for peak half-widths spanning 4-6s. The response toward ten different sulfur compounds was examined and produced an average reproducibility of 1.7% RSD (n=10) and an average equimolarity value of 1.0±0.1. In contrast to this, a conventional single flame S2* mode comparatively yielded respective values of 6.7% RSD (n=10) and 1.1±0.4. HSO* emission in the mFPD was also found to be relatively much less affected by response quenching due to hydrocarbons compared to a conventional single flame S2* emission mode. Results indicate that this new alternative linear mFPD response mode could be beneficial for sulfur monitoring applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. The Atacama B-Mode Search: CMB Polarimetry with Transition-Edge-Sensor Bolometers

    NASA Astrophysics Data System (ADS)

    Essinger-Hileman, T.; Appel, J. W.; Beal, J. A.; Cho, H. M.; Fowler, J.; Halpern, M.; Hasselfield, M.; Irwin, K. D.; Marriage, T. A.; Niemack, M. D.; Page, L.; Parker, L. P.; Pufu, S.; Staggs, S. T.; Stryzak, O.; Visnjic, C.; Yoon, K. W.; Zhao, Y.

    2009-12-01

    The Atacama B-mode Search (ABS) experiment is a 145 GHz polarimeter designed to measure the B-mode polarization of the Cosmic Microwave Background (CMB) at large angular scales. The ABS instrument will ship to the Atacama Desert of Chile fully tested and ready to observe in 2010. ABS will image large-angular-scale CMB polarization anisotropies onto a focal plane of 240 feedhorn-coupled, transition-edge sensor (TES) polarimeters, using a cryogenic crossed-Dragone design. The ABS detectors, which are fabricated at NIST, use orthomode transducers to couple orthogonal polarizations of incoming radiation onto separate TES bolometers. The incoming radiation is modulated by an ambient-temperature half-wave plate in front of the vacuum window at an aperture stop. Preliminary detector characterization indicates that the ABS detectors can achieve a sensitivity of 300 μK√s in the field. This paper describes the ABS optical design and detector readout scheme, including feedhorn design and performance, magnetic shielding, focal plane architecture, and cryogenic electronics.

  18. Linearly polarized vector modes: enabling MIMO-free mode-division multiplexing.

    PubMed

    Wang, Lixian; Nejad, Reza Mirzaei; Corsi, Alessandro; Lin, Jiachuan; Messaddeq, Younès; Rusch, Leslie; LaRochelle, Sophie

    2017-05-15

    We experimentally investigate mode-division multiplexing in an elliptical ring core fiber (ERCF) that supports linearly polarized vector modes (LPV). Characterization show that the ERCF exhibits good polarization maintaining properties over eight LPV modes with effective index difference larger than 1 × 10 -4 . The ERCF further displays stable mode power and polarization extinction ratio when subjected to external perturbations. Crosstalk between the LPV modes, after propagating through 0.9 km ERCF, is below -14 dB. By using six LPV modes as independent data channels, we achieved the transmission of 32 Gbaud QPSK over 0.9 km ERCF without any multiple-input-multiple-output (MIMO) or polarization-division multiplexing (PDM) signal processing.

  19. Half-Metallic Ferromagnetism and Stability of Transition Metal Pnictides and Chalcogenides

    NASA Astrophysics Data System (ADS)

    Liu, Bang-Gui

    It is highly desirable to explore robust half-metallic ferromagnetic materials compatible with important semiconductors for spintronic applications. A state-of-the-art full potential augmented plane wave method within the densityfunctional theory is reliable enough for this purpose. In this chapter we review theoretical research on half-metallic ferromagnetism and structural stability of transition metal pnictides and chalcogenides. We show that some zincblende transition metal pnictides are half-metallic and the half-metallic gap can be fairly wide, which is consistent with experiment. Systematic calculations reveal that zincblende phases of CrTe, CrSe, and VTe are excellent half-metallic ferromagnets. These three materials have wide half-metallic gaps, are low in total energy with respect to the corresponding ground-state phases, and, importantly, are structurally stable. Halfmetallic ferromagnetism is also found in wurtzite transition metal pnictides and chalcogenides and in transition-metal doped semiconductors as well as deformed structures. Some of these half-metallic materials could be grown epitaxially in the form of ultrathin .lms or layers suitable for real spintronic applications.

  20. Few-Mode Whispering-Gallery-Mode Resonators

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy; Strekalov, Dmitry; Matsko, Andrey; Iltchenko, Vladimir; Maleki, Lute

    2006-01-01

    Whispering-gallery-mode (WGM) optical resonators of a type now under development are designed to support few well-defined waveguide modes. In the simplest case, a resonator of this type would support one equatorial family of WGMs; in a more complex case, such a resonator would be made to support two, three, or some other specified finite number of modes. Such a resonator can be made of almost any transparent material commonly used in optics. The nature of the supported modes does not depend on which material is used, and the geometrical dispersion of this resonator is much smaller than that of a typical prior WGM resonator. Moreover, in principle, many such resonators could be fabricated as integral parts of a single chip. Basically, a resonator of this type consists of a rod, made of a suitable transparent material, from which protrudes a thin circumferential belt of the same material. The belt is integral with the rest of the rod (see figure) and acts as a circumferential waveguide. If the depth (d) and width (w) of the belt are made appropriately small, then the belt acts as though it were the core of a single-mode optical fiber: the belt and its adjacent supporting rod material support a single, circumferentially propagating mode or family of modes. It has been shown theoretically that the fiber-optic-like behavior of the belton- rod resonator structure can be summarized, in part, by the difference, Dn, between (1) an effective index of refraction of an imaginary fiber core and (2) the index of refraction (n) of the transparent rod/belt material. It has also been shown theoretically that for a given required value of Dn, the required depth of the belt can be estimated as d R Dn, where R is the radius of the rod. It must be emphasized that this estimated depth is independent of n and, hence, is independent of the choice of rod material. As in the cases of prior WGM resonators, input/output optical coupling involves utilization of evanescent fields. In the

  1. Comparing mode-crosstalk and mode-dependent loss of laterally displaced orbital angular momentum and Hermite-Gaussian modes for free-space optical communication.

    PubMed

    Ndagano, Bienvenu; Mphuthi, Nokwazi; Milione, Giovanni; Forbes, Andrew

    2017-10-15

    There is interest in using orbital angular momentum (OAM) modes to increase the data speed of free-space optical communication. A prevalent challenge is the mitigation of mode-crosstalk and mode-dependent loss that is caused by the modes' lateral displacement at the data receiver. Here, the mode-crosstalk and mode-dependent loss of laterally displaced OAM modes (LG 0,+1 , LG 0,-1 ) are experimentally compared to that of a Hermite-Gaussian (HG) mode subset (HG 0,1 , HG 1,0 ). It is shown, for an aperture larger than the modes' waist sizes, some of the HG modes can experience less mode-crosstalk and mode-dependent loss when laterally displaced along a symmetry axis. It is also shown, over a normal distribution of lateral displacements whose standard deviation is 2× the modes' waist sizes, on average, the HG modes experience 66% less mode-crosstalk and 17% less mode-dependent loss.

  2. Variable optical attenuator and dynamic mode group equalizer for few mode fibers.

    PubMed

    Blau, Miri; Weiss, Israel; Gerufi, Jonathan; Sinefeld, David; Bin-Nun, Moran; Lingle, Robert; Grüner-Nielsen, Lars; Marom, Dan M

    2014-12-15

    Variable optical attenuation (VOA) for three-mode fiber is experimentally presented, utilizing an amplitude spatial light modulator (SLM), achieving up to -28dB uniform attenuation for all modes. Using the ability to spatially vary the attenuation distribution with the SLM, we also achieve up to 10dB differential attenuation between the fiber's two supported mode group (LP₀₁ and LP₁₁). The spatially selective attenuation serves as the basis of a dynamic mode-group equalizer (DME), potentially gain-balancing mode dependent optical amplification. We extend the experimental three mode DME functionality with a performance analysis of a fiber supporting 6 spatial modes in four mode groups. The spatial modes' distribution and overlap limit the available dynamic range and performance of the DME in the higher mode count case.

  3. The dimerization of half-molecule fragments of transferrin.

    PubMed Central

    Williams, J; Moreton, K

    1988-01-01

    Partial proteolysis was used to prepare half-molecule fragments of hen ovotransferrin. N-Terminal and C-terminal fragments associate to form an N-terminal fragment-C-terminal fragment dimer. Variant forms of the N- and C-terminal fragments can be prepared in which a few amino acid residues are lacking from the C-terminal ends of the fragments. These variant fragments are partially or completely unable to associate; the suggestion that the molecular recognition sites are located in these C-terminal stretches of the N-terminal half-molecule (320-332) and of the C-terminal half-molecule (683-686) is in agreement with X-ray-crystallography data for human lactotransferrin [Anderson, Baker, Dodson, Norris, Rumball, Waters & Baker (1987) Proc. Natl. Acad. Sci. U.S.A. 84, 1769-1773]. PMID:3415649

  4. Using Whispering-Gallery-Mode Resonators for Refractometry

    NASA Technical Reports Server (NTRS)

    Matsko, Andrey; Savchenkov, Anatoliy; Strekalov, Dmitry; Iltchenko, Vladimir; Maleki, Lute

    2010-01-01

    A method of determining the refractive and absorptive properties of optically transparent materials involves a combination of theoretical and experimental analysis of electromagnetic responses of whispering-gallery-mode (WGM) resonator disks made of those materials. The method was conceived especially for use in studying transparent photorefractive materials, for which purpose this method affords unprecedented levels of sensitivity and accuracy. The method is expected to be particularly useful for measuring temporally varying refractive and absorptive properties of photorefractive materials at infrared wavelengths. Still more particularly, the method is expected to be useful for measuring drifts in these properties that are so slow that, heretofore, the properties were assumed to be constant. The basic idea of the method is to attempt to infer values of the photorefractive properties of a material by seeking to match (1) theoretical predictions of the spectral responses (or selected features thereof) of a WGM of known dimensions made of the material with (2) the actual spectral responses (or selected features thereof). Spectral features that are useful for this purpose include resonance frequencies, free spectral ranges (differences between resonance frequencies of adjacently numbered modes), and resonance quality factors (Q values). The method has been demonstrated in several experiments, one of which was performed on a WGM resonator made from a disk of LiNbO3 doped with 5 percent of MgO. The free spectral range of the resonator was approximately equal to 3.42 GHz at wavelengths in the vicinity of 780 nm, the smallest full width at half maximum of a mode was approximately equal to 50 MHz, and the thickness of the resonator in the area of mode localization was 30 microns. In the experiment, laser power of 9 mW was coupled into the resonator with an efficiency of 75 percent, and the laser was scanned over a frequency band 9 GHz wide at a nominal wavelength of

  5. Chiral topological superconductor and half-integer conductance plateau from quantum anomalous Hall plateau transition

    DOE PAGES

    Wang, Jing; Zhou, Quan; Lian, Biao; ...

    2015-08-31

    Here, we propose to realize a two-dimensional chiral topological superconducting (TSC) state from the quantum anomalous Hall plateau transition in a magnetic topological insulator thin film through the proximity effect to a conventional s -wave superconductor. This state has a full pairing gap in the bulk and a single chiral Majorana mode at the edge. The optimal condition for realizing such chiral TSC is to have inequivalent superconducting pairing amplitudes on top and bottom surfaces of the doped magnetic topological insulator. We further propose several transport experiments to detect the chiral TSC. One unique signature is that the conductance willmore » be quantized into a half-integer plateau at the coercive field in this hybrid system. In particular, with the point contact formed by a superconducting junction, the conductance oscillates between e 2 /2h and e2 /h with the frequency determined by the voltage across the junction. We close by discussing the feasibility of these experimental proposals.« less

  6. Chiral topological superconductor and half-integer conductance plateau from quantum anomalous Hall plateau transition

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

    Wang, Jing; Zhou, Quan; Lian, Biao

    Here, we propose to realize a two-dimensional chiral topological superconducting (TSC) state from the quantum anomalous Hall plateau transition in a magnetic topological insulator thin film through the proximity effect to a conventional s -wave superconductor. This state has a full pairing gap in the bulk and a single chiral Majorana mode at the edge. The optimal condition for realizing such chiral TSC is to have inequivalent superconducting pairing amplitudes on top and bottom surfaces of the doped magnetic topological insulator. We further propose several transport experiments to detect the chiral TSC. One unique signature is that the conductance willmore » be quantized into a half-integer plateau at the coercive field in this hybrid system. In particular, with the point contact formed by a superconducting junction, the conductance oscillates between e 2 /2h and e2 /h with the frequency determined by the voltage across the junction. We close by discussing the feasibility of these experimental proposals.« less

  7. Mode coupling in hybrid square-rectangular lasers for single mode operation

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

    Ma, Xiu-Wen; Huang, Yong-Zhen, E-mail: yzhuang@semi.ac.cn; Yang, Yue-De

    Mode coupling between a square microcavity and a Fabry-Pérot (FP) cavity is proposed and demonstrated for realizing single mode lasers. The modulations of the mode Q factor as simulation results are observed and single mode operation is obtained with a side mode suppression ratio of 46 dB and a single mode fiber coupling loss of 3.2 dB for an AlGaInAs/InP hybrid laser as a 300-μm-length and 1.5-μm-wide FP cavity connected to a vertex of a 10-μm-side square microcavity. Furthermore, tunable single mode operation is demonstrated with a continuous wavelength tuning range over 10 nm. The simple hybrid structure may shed light on practicalmore » applications of whispering-gallery mode microcavities in large-scale photonic integrated circuits and optical communication and interconnection.« less

  8. Data characteristics and preliminary results from the atacama b-mode search (ABS)

    NASA Astrophysics Data System (ADS)

    Visnjic, Catherine

    The Atacama B-Mode Search (ABS) is a 145 GHz polarimeter located at a high altitude site on Cerro Toco, in the Andes of northern Chile. Having deployed in early 2012, it is currently in its second year of operation, observing the polarization of the Cosmic Microwave Background (CMB). It seeks to probe the as yet undetected odd-parity B-modes of the polarization, which would have been created by the primordial gravitational wave background (GWB) predicted by theories of inflation. The magnitude of the B-mode signal is characterized by the tensor-to-scalar ratio, r. ABS features 60 cm cryogenic reflectors in the crossed-Dragone configuration, and a warm, continuously rotating sapphire half-wave plate to modulate the polarization of incoming radiation. The focal plane consists of 480 antenna-coupled transition edge sensor bolometers, arranged in orthogonal pairs for polarization sensitivity, and coupled to feedhorns in a hexagonal array. In this thesis we describe the ABS instrument in the state in which it is now operating, outline the first season of observations, and characterize the data obtained. Focusing on observations of the primary CMB field during a one month reference period, we detail the algorithms currently used to select the data suitable for making maps. This is the first pass at data cuts and provides a conservative estimate for the sensitivity of ABS to the polarization modes in the sky. We project that with one year total observation time of the primary CMB field, ABS should be able to detect the B-mode signal at roughly the level of r = 0.03.

  9. Fast Generation of Ensembles of Cosmological N-Body Simulations via Mode-Resampling

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

    Schneider, M D; Cole, S; Frenk, C S

    2011-02-14

    We present an algorithm for quickly generating multiple realizations of N-body simulations to be used, for example, for cosmological parameter estimation from surveys of large-scale structure. Our algorithm uses a new method to resample the large-scale (Gaussian-distributed) Fourier modes in a periodic N-body simulation box in a manner that properly accounts for the nonlinear mode-coupling between large and small scales. We find that our method for adding new large-scale mode realizations recovers the nonlinear power spectrum to sub-percent accuracy on scales larger than about half the Nyquist frequency of the simulation box. Using 20 N-body simulations, we obtain a powermore » spectrum covariance matrix estimate that matches the estimator from Takahashi et al. (from 5000 simulations) with < 20% errors in all matrix elements. Comparing the rates of convergence, we determine that our algorithm requires {approx}8 times fewer simulations to achieve a given error tolerance in estimates of the power spectrum covariance matrix. The degree of success of our algorithm indicates that we understand the main physical processes that give rise to the correlations in the matter power spectrum. Namely, the large-scale Fourier modes modulate both the degree of structure growth through the variation in the effective local matter density and also the spatial frequency of small-scale perturbations through large-scale displacements. We expect our algorithm to be useful for noise modeling when constraining cosmological parameters from weak lensing (cosmic shear) and galaxy surveys, rescaling summary statistics of N-body simulations for new cosmological parameter values, and any applications where the influence of Fourier modes larger than the simulation size must be accounted for.« less

  10. Precise half-life measurement of the superallowed emitter 30S

    NASA Astrophysics Data System (ADS)

    Iacob, V. E.; Hardy, J. C.; Chen, L.; Horvat, V.; Bencomo, M.; Nica, N.; Park, H. I.; Roeder, B. T.; Saastamoinen, A.

    2018-03-01

    We have measured the half-life of 30S, the parent of a superallowed 0+→0+β transition, to a high precision using very pure sources and a 4 π proportional gas counter to detect the decay positrons. Our result for the half-life is 1.179 92(34) s. As a by-product of this measurement, we determine the half-life of its daughter, 30P, to be 2.501(2) min.

  11. Edge-localized mode avoidance and pedestal structure in I-mode plasmasa)

    NASA Astrophysics Data System (ADS)

    Walk, J. R.; Hughes, J. W.; Hubbard, A. E.; Terry, J. L.; Whyte, D. G.; White, A. E.; Baek, S. G.; Reinke, M. L.; Theiler, C.; Churchill, R. M.; Rice, J. E.; Snyder, P. B.; Osborne, T.; Dominguez, A.; Cziegler, I.

    2014-05-01

    I-mode is a high-performance tokamak regime characterized by the formation of a temperature pedestal and enhanced energy confinement, without an accompanying density pedestal or drop in particle and impurity transport. I-mode operation appears to have naturally occurring suppression of large Edge-Localized Modes (ELMs) in addition to its highly favorable scalings of pedestal structure and overall performance. Extensive study of the ELMy H-mode has led to the development of the EPED model, which utilizes calculations of coupled peeling-ballooning MHD modes and kinetic-ballooning mode (KBM) stability limits to predict the pedestal structure preceding an ELM crash. We apply similar tools to the structure and ELM stability of I-mode pedestals. Analysis of I-mode discharges prepared with high-resolution pedestal data from the most recent C-Mod campaign reveals favorable pedestal scalings for extrapolation to large machines—pedestal temperature scales strongly with power per particle Pnet/n ¯e, and likewise pedestal pressure scales as the net heating power (consistent with weak degradation of confinement with heating power). Matched discharges in current, field, and shaping demonstrate the decoupling of energy and particle transport in I-mode, increasing fueling to span nearly a factor of two in density while maintaining matched temperature pedestals with consistent levels of Pnet/n ¯e. This is consistent with targets for increased performance in I-mode, elevating pedestal βp and global performance with matched increases in density and heating power. MHD calculations using the ELITE code indicate that I-mode pedestals are strongly stable to edge peeling-ballooning instabilities. Likewise, numerical modeling of the KBM turbulence onset, as well as scalings of the pedestal width with poloidal beta, indicates that I-mode pedestals are not limited by KBM turbulence—both features identified with the trigger for large ELMs, consistent with the observed suppression of

  12. The Global Mode-1 S2 Internal Tide

    NASA Astrophysics Data System (ADS)

    Zhao, Zhongxiang

    2017-11-01

    The global mode-1 S2 internal tide is observed using sea surface height (SSH) measurements from four satellite altimeters: TOPEX/Poseidon, Jason-1, Jason-2, and Geosat Follow-On. Plane wave analysis is employed to extract three mode-1 S2 internal tidal waves in any given 250 km by 250 km window, which are temporally coherent over a 20 year period from 1992 to 2012. Depth-integrated energy and flux of the S2 internal tide are calculated from the SSH amplitude and a conversion function built from climatological hydrographic profiles in the World Ocean Atlas 2013. The results show that the S2 and M2 internal tides have similar spatial patterns. Both S2 and M2 internal tides originate at major topographic features and propagate over long distances. The S2 internal tidal beams are generally shorter, likely because the relatively weaker S2 internal tide is easily overwhelmed by nontidal noise. The northbound S2 and M2 internal tides from the Hawaiian Ridge are observed to travel over 3500 km across the Northeast Pacific. The globally integrated energy of the mode-1 S2 internal tide is 7.8 PJ (1 PJ = 1015 J), about 20% that of M2 (36.4 PJ). The histogram of S2 to M2 SSH ratios peaks at 0.4, consistent with the square root of their energy ratio. In terms of SSH, S2 is greater than M2 in ≈10% of the global ocean and ≥50% of M2 in about half of the global ocean.

  13. Flexible Modes Control Using Sliding Mode Observers: Application to Ares I

    NASA Technical Reports Server (NTRS)

    Shtessel, Yuri B.; Hall, Charles E.; Baev, Simon; Orr, Jeb S.

    2010-01-01

    The launch vehicle dynamics affected by bending and sloshing modes are considered. Attitude measurement data that are corrupted by flexible modes could yield instability of the vehicle dynamics. Flexible body and sloshing modes are reconstructed by sliding mode observers. The resultant estimates are used to remove the undesirable dynamics from the measurements, and the direct effects of sloshing and bending modes on the launch vehicle are compensated by means of a controller that is designed without taking the bending and sloshing modes into account. A linearized mathematical model of Ares I launch vehicle was derived based on FRACTAL, a linear model developed by NASA/MSFC. The compensated vehicle dynamics with a simple PID controller were studied for the launch vehicle model that included two bending modes, two slosh modes and actuator dynamics. A simulation study demonstrated stable and accurate performance of the flight control system with the augmented simple PID controller without the use of traditional linear bending filters.

  14. Global dynamics of a nonlocal delayed reaction-diffusion equation on a half plane

    NASA Astrophysics Data System (ADS)

    Hu, Wenjie; Duan, Yueliang

    2018-04-01

    We consider a delayed reaction-diffusion equation with spatial nonlocality on a half plane that describes population dynamics of a two-stage species living in a semi-infinite environment. A Neumann boundary condition is imposed accounting for an isolated domain. To describe the global dynamics, we first establish some a priori estimate for nontrivial solutions after investigating asymptotic properties of the nonlocal delayed effect and the diffusion operator, which enables us to show the permanence of the equation with respect to the compact open topology. We then employ standard dynamical system arguments to establish the global attractivity of the nontrivial equilibrium. The main results are illustrated by the diffusive Nicholson's blowfly equation and the diffusive Mackey-Glass equation.

  15. Mode selection in square resonator microlasers for widely tunable single mode lasing.

    PubMed

    Tang, Ming-Ying; Sui, Shao-Shuai; Yang, Yue-De; Xiao, Jin-Long; Du, Yun; Huang, Yong-Zhen

    2015-10-19

    Mode selection in square resonator semiconductor microlasers is demonstrated by adjusting the width of the output waveguide coupled to the midpoint of one side. The simulation and experimental results reveal that widely tunable single mode lasing can be realized in square resonator microlasers. Through adjusting the width of the output waveguide, the mode interval of the high-Q modes can reach four times of the longitudinal mode interval. Therefore, mode hopping can be efficiently avoided and the lasing wavelength can be tuned continuously by tuning the injection current. For a 17.8-μm-side-length square microlaser with a 1.4-μm-width output waveguide, mode-hopping-free single-mode operation is achieved with a continuous tuning range of 9.2 nm. As a result, the control of the lasing mode is realized for the square microlasers.

  16. Adaptive variational mode decomposition method for signal processing based on mode characteristic

    NASA Astrophysics Data System (ADS)

    Lian, Jijian; Liu, Zhuo; Wang, Haijun; Dong, Xiaofeng

    2018-07-01

    Variational mode decomposition is a completely non-recursive decomposition model, where all the modes are extracted concurrently. However, the model requires a preset mode number, which limits the adaptability of the method since a large deviation in the number of mode set will cause the discard or mixing of the mode. Hence, a method called Adaptive Variational Mode Decomposition (AVMD) was proposed to automatically determine the mode number based on the characteristic of intrinsic mode function. The method was used to analyze the simulation signals and the measured signals in the hydropower plant. Comparisons have also been conducted to evaluate the performance by using VMD, EMD and EWT. It is indicated that the proposed method has strong adaptability and is robust to noise. It can determine the mode number appropriately without modulation even when the signal frequencies are relatively close.

  17. Mode division multiplexing using an orbital angular momentum mode sorter and MIMO-DSP over a graded-index few-mode optical fibre

    PubMed Central

    Huang, Hao; Milione, Giovanni; Lavery, Martin P. J.; Xie, Guodong; Ren, Yongxiong; Cao, Yinwen; Ahmed, Nisar; An Nguyen, Thien; Nolan, Daniel A.; Li, Ming-Jun; Tur, Moshe; Alfano, Robert R.; Willner, Alan E.

    2015-01-01

    Mode division multiplexing (MDM)– using a multimode optical fiber’s N spatial modes as data channels to transmit N independent data streams – has received interest as it can potentially increase optical fiber data transmission capacity N-times with respect to single mode optical fibers. Two challenges of MDM are (1) designing mode (de)multiplexers with high mode selectivity (2) designing mode (de)multiplexers without cascaded beam splitting’s 1/N insertion loss. One spatial mode basis that has received interest is that of orbital angular momentum (OAM) modes. In this paper, using a device referred to as an OAM mode sorter, we show that OAM modes can be (de)multiplexed over a multimode optical fiber with higher than −15 dB mode selectivity and without cascaded beam splitting’s 1/N insertion loss. As a proof of concept, the OAM modes of the LP11 mode group (OAM−1,0 and OAM+1,0), each carrying 20-Gbit/s polarization division multiplexed and quadrature phase shift keyed data streams, are transmitted 5km over a graded-index, few-mode optical fibre. Channel crosstalk is mitigated using 4 × 4 multiple-input-multiple-output digital-signal-processing with <1.5 dB power penalties at a bit-error-rate of 2 × 10−3. PMID:26450398

  18. Mode division multiplexing using an orbital angular momentum mode sorter and MIMO-DSP over a graded-index few-mode optical fibre.

    PubMed

    Huang, Hao; Milione, Giovanni; Lavery, Martin P J; Xie, Guodong; Ren, Yongxiong; Cao, Yinwen; Ahmed, Nisar; An Nguyen, Thien; Nolan, Daniel A; Li, Ming-Jun; Tur, Moshe; Alfano, Robert R; Willner, Alan E

    2015-10-09

    Mode division multiplexing (MDM)- using a multimode optical fiber's N spatial modes as data channels to transmit N independent data streams - has received interest as it can potentially increase optical fiber data transmission capacity N-times with respect to single mode optical fibers. Two challenges of MDM are (1) designing mode (de)multiplexers with high mode selectivity (2) designing mode (de)multiplexers without cascaded beam splitting's 1/N insertion loss. One spatial mode basis that has received interest is that of orbital angular momentum (OAM) modes. In this paper, using a device referred to as an OAM mode sorter, we show that OAM modes can be (de)multiplexed over a multimode optical fiber with higher than -15 dB mode selectivity and without cascaded beam splitting's 1/N insertion loss. As a proof of concept, the OAM modes of the LP11 mode group (OAM-1,0 and OAM+1,0), each carrying 20-Gbit/s polarization division multiplexed and quadrature phase shift keyed data streams, are transmitted 5km over a graded-index, few-mode optical fibre. Channel crosstalk is mitigated using 4 × 4 multiple-input-multiple-output digital-signal-processing with <1.5 dB power penalties at a bit-error-rate of 2 × 10(-3).

  19. Mode division multiplexing using an orbital angular momentum mode sorter and MIMO-DSP over a graded-index few-mode optical fibre

    NASA Astrophysics Data System (ADS)

    Huang, Hao; Milione, Giovanni; Lavery, Martin P. J.; Xie, Guodong; Ren, Yongxiong; Cao, Yinwen; Ahmed, Nisar; An Nguyen, Thien; Nolan, Daniel A.; Li, Ming-Jun; Tur, Moshe; Alfano, Robert R.; Willner, Alan E.

    2015-10-01

    Mode division multiplexing (MDM)- using a multimode optical fiber’s N spatial modes as data channels to transmit N independent data streams - has received interest as it can potentially increase optical fiber data transmission capacity N-times with respect to single mode optical fibers. Two challenges of MDM are (1) designing mode (de)multiplexers with high mode selectivity (2) designing mode (de)multiplexers without cascaded beam splitting’s 1/N insertion loss. One spatial mode basis that has received interest is that of orbital angular momentum (OAM) modes. In this paper, using a device referred to as an OAM mode sorter, we show that OAM modes can be (de)multiplexed over a multimode optical fiber with higher than -15 dB mode selectivity and without cascaded beam splitting’s 1/N insertion loss. As a proof of concept, the OAM modes of the LP11 mode group (OAM-1,0 and OAM+1,0), each carrying 20-Gbit/s polarization division multiplexed and quadrature phase shift keyed data streams, are transmitted 5km over a graded-index, few-mode optical fibre. Channel crosstalk is mitigated using 4 × 4 multiple-input-multiple-output digital-signal-processing with <1.5 dB power penalties at a bit-error-rate of 2 × 10-3.

  20. Mode perturbation method for optimal guided wave mode and frequency selection.

    PubMed

    Philtron, J H; Rose, J L

    2014-09-01

    With a thorough understanding of guided wave mechanics, researchers can predict which guided wave modes will have a high probability of success in a particular nondestructive evaluation application. However, work continues to find optimal mode and frequency selection for a given application. This "optimal" mode could give the highest sensitivity to defects or the greatest penetration power, increasing inspection efficiency. Since material properties used for modeling work may be estimates, in many cases guided wave mode and frequency selection can be adjusted for increased inspection efficiency in the field. In this paper, a novel mode and frequency perturbation method is described and used to identify optimal mode points based on quantifiable wave characteristics. The technique uses an ultrasonic phased array comb transducer to sweep in phase velocity and frequency space. It is demonstrated using guided interface waves for bond evaluation. After searching nearby mode points, an optimal mode and frequency can be selected which has the highest sensitivity to a defect, or gives the greatest penetration power. The optimal mode choice for a given application depends on the requirements of the inspection. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Research of the impact of coupling between unit cells on performance of linear-to-circular polarization conversion metamaterial with half transmission and half reflection

    NASA Astrophysics Data System (ADS)

    Guo, Mengchao; Zhou, Kan; Wang, Xiaokun; Zhuang, Haiyan; Tang, Dongming; Zhang, Baoshan; Yang, Yi

    2018-04-01

    In this paper, the impact of coupling between unit cells on the performance of linear-to-circular polarization conversion metamaterial with half transmission and half reflection is analyzed by changing the distance between the unit cells. An equivalent electrical circuit model is then built to explain it based on the analysis. The simulated results show that, when the distance between the unit cells is 23 mm, this metamaterial converts half of the incident linearly-polarized wave into reflected left-hand circularly-polarized wave and converts the other half of it into transmitted left-hand circularly-polarized wave at 4.4 GHz; when the distance is 28 mm, this metamaterial reflects all of the incident linearly-polarized wave at 4.4 GHz; and when the distance is 32 mm, this metamaterial converts half of the incident linearly-polarized wave into reflected right-hand circularly-polarized wave and converts the other half of it into transmitted right-hand circularly-polarized wave at 4.4 GHz. The tunability is realized successfully. The analysis shows that the changes of coupling between unit cells lead to the changes of performance of this metamaterial. The coupling between the unit cells is then considered when building the equivalent electrical circuit model. The built equivalent electrical circuit model can be used to perfectly explain the simulated results, which confirms the validity of it. It can also give help to the design of tunable polarization conversion metamaterials.

  2. Scattering of three-dimensional plane waves in a self-reinforced half-space lying over a triclinic half-space

    NASA Astrophysics Data System (ADS)

    Gupta, Shishir; Pramanik, Abhijit; Smita; Pramanik, Snehamoy

    2018-06-01

    The phenomenon of plane waves at the intersecting plane of a triclinic half-space and a self-reinforced half-space is discussed with possible applications during wave propagation. Analytical expressions of the phase velocities of reflection and refraction for quasi-compressional and quasi-shear waves under initial stress are discussed carefully. The closest form of amplitude proportions on reflection and refraction factors of three quasi-plane waves are developed mathematically by applying appropriate boundary conditions. Graphics are sketched to exhibit the consequences of initial stress in the three-dimensional plane wave on reflection and refraction coefficients. Some special cases that coincide with the fundamental properties of several layers are designed to express the reflection and refraction coefficients.

  3. Influence of curing mode with a LED unit on polymerization contraction kinetics and degree of conversion of dental resin-based materials.

    PubMed

    Mortier, Eric; Simon, Yorick; Dahoun, Abdelsellam; Gerdolle, David

    2009-01-01

    The purpose of this study was to evaluate the influence of photopolymerization mode with a light emitting diode (LED) lamp on the curing contraction kinetics and degree of conversion of 3 resin-based restorative materials. The curing contraction kinetics of Admira (ADM), Filtek P60 (P60), and Filtek Flow (FLO) were measured by the glass slide method. The materials were exposed to light from a 1,000 mW/cm-(2) power LED lamp (Elipar Freelight 2) in 3 modes: 2 continuous modes of 20 and 40 seconds (C20 and C40), and 1 exponential mode (E20; 5 seconds of exponential power increase followed by 15 seconds of maximum intensity). The degree of conversion (DC) was measured for each of the materials, and each of the modes by Fourier transformed infra-red spectrometry. P60 had the significantly lowest final contraction and FLO the highest among all light exposure modes. The C20 and C40 modes did not produce any difference in contraction or degree of conversion. The E20 mode led to a significant slowing of contraction speed combined with greater final contraction. Use of a LED lamp (1,000 mW/cm2) in continuous mode reduces the exposure time by half for identical curing shrinkage and degree of conversion.

  4. Effects of low and high mode number tearing modes in divertor tokamaks

    NASA Astrophysics Data System (ADS)

    Punjabi, Alkesh; Ali, Halima; Boozer, Allen; Evans, Todd

    2007-08-01

    The topological effects of magnetic perturbations on a divertor tokamak, such as DIII-D, are studied using field-line maps that were developed by Punjabi et al. [A. Punjabi, A. Verma, and A. Boozer, Phys. Rev. Lett. 69, 3322 (1992)]. The studies consider both long-wavelength perturbations, such as those of m =1, n =1 tearing modes, and localized perturbations, which are represented as a magnetic dipole. The parameters of the dipole map are set using DIII-D data from shot 115467 in which the C-coils were activated [J. L. Luxon and L. E. Davis, Fusion Technol. 8, 441 (1985)]. The long-wavelength perturbations alter the structure of the interception of magnetic field lines with the divertor plates, but the interception is in sharp lines. The dipole perturbations cause a spreading of the interception of the field lines with the divertor plates, which alleviates problems associated with heat deposition. Magnetic field lines are the trajectories of a one-and-a-half degree of freedom Hamiltonian, which strongly constrains the topological features of the lines. Although the field line maps that we use do not accurately represent the trajectories through ordinary space of individual field lines, they do represent their topological structure.

  5. SART-Type Half-Threshold Filtering Approach for CT Reconstruction

    PubMed Central

    YU, HENGYONG; WANG, GE

    2014-01-01

    The ℓ1 regularization problem has been widely used to solve the sparsity constrained problems. To enhance the sparsity constraint for better imaging performance, a promising direction is to use the ℓp norm (0 < p < 1) and solve the ℓp minimization problem. Very recently, Xu et al. developed an analytic solution for the ℓ1∕2 regularization via an iterative thresholding operation, which is also referred to as half-threshold filtering. In this paper, we design a simultaneous algebraic reconstruction technique (SART)-type half-threshold filtering framework to solve the computed tomography (CT) reconstruction problem. In the medical imaging filed, the discrete gradient transform (DGT) is widely used to define the sparsity. However, the DGT is noninvertible and it cannot be applied to half-threshold filtering for CT reconstruction. To demonstrate the utility of the proposed SART-type half-threshold filtering framework, an emphasis of this paper is to construct a pseudoinverse transforms for DGT. The proposed algorithms are evaluated with numerical and physical phantom data sets. Our results show that the SART-type half-threshold filtering algorithms have great potential to improve the reconstructed image quality from few and noisy projections. They are complementary to the counterparts of the state-of-the-art soft-threshold filtering and hard-threshold filtering. PMID:25530928

  6. SART-Type Half-Threshold Filtering Approach for CT Reconstruction.

    PubMed

    Yu, Hengyong; Wang, Ge

    2014-01-01

    The [Formula: see text] regularization problem has been widely used to solve the sparsity constrained problems. To enhance the sparsity constraint for better imaging performance, a promising direction is to use the [Formula: see text] norm (0 < p < 1) and solve the [Formula: see text] minimization problem. Very recently, Xu et al. developed an analytic solution for the [Formula: see text] regularization via an iterative thresholding operation, which is also referred to as half-threshold filtering. In this paper, we design a simultaneous algebraic reconstruction technique (SART)-type half-threshold filtering framework to solve the computed tomography (CT) reconstruction problem. In the medical imaging filed, the discrete gradient transform (DGT) is widely used to define the sparsity. However, the DGT is noninvertible and it cannot be applied to half-threshold filtering for CT reconstruction. To demonstrate the utility of the proposed SART-type half-threshold filtering framework, an emphasis of this paper is to construct a pseudoinverse transforms for DGT. The proposed algorithms are evaluated with numerical and physical phantom data sets. Our results show that the SART-type half-threshold filtering algorithms have great potential to improve the reconstructed image quality from few and noisy projections. They are complementary to the counterparts of the state-of-the-art soft-threshold filtering and hard-threshold filtering.

  7. Mode identification from spectroscopy of gravity-mode pulsators

    NASA Astrophysics Data System (ADS)

    Pollard, K. R.; Brunsden, E.; Cottrell, P. L.; Davie, M.; Greenwood, A.; Wright, D. J.; De Cat, P.

    2014-02-01

    The gravity modes present in γ Doradus stars probe the deep stellar interiors and are thus of particular interest in asteroseismology. For the MUSICIAN programme at the University of Canterbury, we obtain extensive high-resolution echelle spectra of γ Dor stars from the Mt John University Observatory in New Zealand. We analyze these to obtain the pulsational frequencies and identify these with the multiple pulsational modes excited in the star. A summary of recent results from our spectroscopic mode-identification programme is given.

  8. U.N.: AIDS likely to kill half of teens in worst-hit nations.

    PubMed

    In the report of the Joint UN Programme on HIV/AIDS (UNAIDS) released on June 27, 2000, it is projected that AIDS is expected to kill half of the teenagers in some African nations, devastating economies and societies. Moreover, the UNAIDS estimated that the virus has killed 19 million people worldwide; that more than 13 million children have been orphaned; that in 16 sub-Saharan countries more than one-tenth of the population aged 15-49 is infected with HIV; and that in 7 of these countries at least one-fifth of the population is infected. Peter Piot, head of UNAIDS believes that legacy apartheid and governmental disregard of the problem are reasons for the AIDS epidemic in southern Africa. In view of this, the report urgently underscores the need for government leaders to face the crisis head on, engaging all sectors of society in the battle against the epidemic. A number of prevention initiatives are discussed and studies are cited regarding success of such AIDS-preventive strategies.

  9. Characterizing the ``Higgs'' amplitude mode in a Spin-1 Bose Einstein Condensate

    NASA Astrophysics Data System (ADS)

    Hebbe Madhusudhana, Bharath; Boguslawski, Matthew; Anquez, Martin; Robbins, Bryce; Barrios, Maryrose; Hoang, Thai; Chapman, Michael

    2016-05-01

    Spontaneous symmetry breaking in a physical system is often characterized by massless Nambu-Goldstone modes and massive Anderson-Higgs modes. It occurs when a system crosses a quantum critical point (QCP) reaching a state does not share the symmetry of the underlying Hamiltonian. In a spin-1 Bose Einstein condensate, the transverse spin component can be considered as an order parameter. A quantum phase transition (QPT) of this system results in breaking of the symmetry group U(1) × SO(2) shared by the Hamiltonian. As a result, two massless coupled phonon-magnon modes are produced along with a single massive mode or a Higgs-like mode, in the form of amplitude excitations of the order parameter. Here we characterize the amplitude excitations experimentally by inducing coherent oscillation in the spin population. We further use the amplitude oscillations to measure the energy gap for different phases of the QPT. At the QCP, finite size effects lead to a non-zero gap, and our measurements are consistent with this prediction.

  10. Predictor variables for half marathon race time in recreational female runners.

    PubMed

    Knechtle, Beat; Knechtle, Patrizia; Barandun, Ursula; Rosemann, Thomas; Lepers, Romuald

    2011-01-01

    The relationship between skin-fold thickness and running performance has been investigated from 100 m to the marathon distance, except the half marathon distance. To investigate whether anthropometry characteristics or training practices were related to race time in 42 recreational female half marathoners to determine the predictor variables of half-marathon race time and to inform future novice female half marathoners. Observational field study at the 'Half Marathon Basel' in Switzerland. In the bivariate analysis, body mass (r = 0.60), body mass index (r = 0.48), body fat (r = 0.56), skin-fold at pectoral (r = 0.61), mid-axilla (r = 0.69), triceps (r = 0.49), subscapular (r = 0.61), abdominal (r = 0.59), suprailiac (r = 0.55) medial calf (r = 0.53) site, and speed of the training sessions (r = -0.68) correlated to race time. Mid-axilla skin-fold (p = 0.04) and speed of the training sessions (p = 0.0001) remained significant after multi-variate analysis. Race time in a half marathon might be predicted by the following equation (r² = 0.71): Race time (min) = 166.7 + 1.7x (mid-axilla skin-fold, mm) - 6.4x (speed in training, km/h). Running speed during training was related to skinfold thickness at mid-axilla (r = -0.31), subscapular (r = -0.38), abdominal (r = -0.44), suprailiacal (r = -0.41), the sum of eight skin-folds (r = -0.36) and percent body fat (r = -0.31). Anthropometric and training variables were related to half-marathon race time in recreational female runners. Skin-fold thicknesses at various upper body locations were related to training intensity. High running speed in training appears to be important for fast half-marathon race times and may reduce upper body skin-fold thicknesses in recreational female half marathoners.

  11. Parametric Oscillation, Frequency Mixing, and Injection Locking of Strongly Coupled Nanomechanical Resonator Modes.

    PubMed

    Seitner, Maximilian J; Abdi, Mehdi; Ridolfo, Alessandro; Hartmann, Michael J; Weig, Eva M

    2017-06-23

    We study locking phenomena of two strongly coupled, high quality factor nanomechanical resonator modes to a common parametric drive at a single drive frequency in different parametric driving regimes. By controlled dielectric gradient forces we tune the resonance frequencies of the flexural in-plane and out-of-plane oscillation of the high stress silicon nitride string through their mutual avoided crossing. For the case of the strong common parametric drive signal-idler generation via nondegenerate parametric two-mode oscillation is observed. Broadband frequency tuning of the very narrow linewidth signal and idler resonances is demonstrated. When the resonance frequencies of the signal and idler get closer to each other, partial injection locking, injection pulling, and complete injection locking to half of the drive frequency occurs depending on the pump strength. Furthermore, satellite resonances, symmetrically offset from the signal and idler by their beat note, are observed, which can be attributed to degenerate four-wave mixing in the highly nonlinear mechanical oscillations.

  12. Edge-localized mode avoidance and pedestal structure in I-mode plasmas

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

    Walk, J. R., E-mail: jrwalk@psfc.mit.edu; Hughes, J. W.; Hubbard, A. E.

    I-mode is a high-performance tokamak regime characterized by the formation of a temperature pedestal and enhanced energy confinement, without an accompanying density pedestal or drop in particle and impurity transport. I-mode operation appears to have naturally occurring suppression of large Edge-Localized Modes (ELMs) in addition to its highly favorable scalings of pedestal structure and overall performance. Extensive study of the ELMy H-mode has led to the development of the EPED model, which utilizes calculations of coupled peeling-ballooning MHD modes and kinetic-ballooning mode (KBM) stability limits to predict the pedestal structure preceding an ELM crash. We apply similar tools to themore » structure and ELM stability of I-mode pedestals. Analysis of I-mode discharges prepared with high-resolution pedestal data from the most recent C-Mod campaign reveals favorable pedestal scalings for extrapolation to large machines—pedestal temperature scales strongly with power per particle P{sub net}/n{sup ¯}{sub e}, and likewise pedestal pressure scales as the net heating power (consistent with weak degradation of confinement with heating power). Matched discharges in current, field, and shaping demonstrate the decoupling of energy and particle transport in I-mode, increasing fueling to span nearly a factor of two in density while maintaining matched temperature pedestals with consistent levels of P{sub net}/n{sup ¯}{sub e}. This is consistent with targets for increased performance in I-mode, elevating pedestal β{sub p} and global performance with matched increases in density and heating power. MHD calculations using the ELITE code indicate that I-mode pedestals are strongly stable to edge peeling-ballooning instabilities. Likewise, numerical modeling of the KBM turbulence onset, as well as scalings of the pedestal width with poloidal beta, indicates that I-mode pedestals are not limited by KBM turbulence—both features identified with the trigger for large ELMs

  13. Low-bending loss and single-mode operation in few-mode optical fiber

    NASA Astrophysics Data System (ADS)

    Yin, Ping; Wang, Hua; Chen, Ming-Yang; Wei, Jin; Cai, Zhi-Min; Li, Lu-Ming; Yang, Ji-Hai; Zhu, Yuan-Feng

    2016-10-01

    The technique of eliminating the higher-order modes in a few-mode optical fiber is proposed. The fiber is designed with a group of defect modes in the cladding. The higher-order modes in the fiber can be eliminated by bending the fiber to induce strong coupling between the defect modes and the higher-order modes. Numerical simulation shows the bending losses of the LP01 mode are lower than 1.5×10-4 dB/turn for the wavelength shorter than 1.625 μm. The proposed fiber can be bent multiple turns at small bending radius which are preferable for FTTH related applications.

  14. Half-life of the superallowed β+ emitter Ne18

    NASA Astrophysics Data System (ADS)

    Grinyer, G. F.; Smith, M. B.; Andreoiu, C.; Andreyev, A. N.; Ball, G. C.; Bricault, P.; Chakrawarthy, R. S.; Daoud, J. J.; Finlay, P.; Garrett, P. E.; Hackman, G.; Hyland, B.; Leslie, J. R.; Morton, A. C.; Pearson, C. J.; Phillips, A. A.; Schumaker, M. A.; Svensson, C. E.; Valiente-Dobón, J. J.; Williams, S. J.; Zganjar, E. F.

    2007-08-01

    The half-life of Ne18 has been determined by detecting 1042-keV γ rays in the daughter F18 following the superallowed-Fermi β+ decay of samples implanted at the center of the 8πγ-ray spectrometer, a spherical array of 20 HPGe detectors. Radioactive Ne18 beams were produced on-line, mass-separated, and ionized using an electron-cyclotron-resonance ionization source at the ISAC facility at TRIUMF in Vancouver, Canada. This is the first high-precision half-life measurement of a superallowed Fermi β decay to utilize both a large-scale HPGe spectrometer and the isotope separation on-line technique. The half-life of Ne18, 1.6656 ± 0.0019 s, deduced following a 1.4σ correction for detector pulse pile-up, is four times more precise than the previous world average. As part of an investigation into potential systematic effects, the half-life of the heavier isotope Ne23 was determined to be 37.11 ± 0.06 s, a factor of 2 improvement over the previous precision.

  15. Plasma Modes

    NASA Astrophysics Data System (ADS)

    Dubin, D. H. E.

    This chapter explores several aspects of the linear electrostatic normal modes of oscillation for a single-species non-neutral plasma in a Penning trap. Linearized fluid equations of motion are developed, assuming the plasma is cold but collisionless, which allow derivation of the cold plasma dielectric tensor and the electrostatic wave equation. Upper hybrid and magnetized plasma waves in an infinite uniform plasma are described. The effect of the plasma surface in a bounded plasma system is considered, and the properties of surface plasma waves are characterized. The normal modes of a cylindrical plasma column are discussed, and finally, modes of spheroidal plasmas, and finite temperature effects on the modes, are briefly described.

  16. A Cr4+:YAG passively Q-switched Nd:YVO4 microchip laser for controllable high-order Hermite-Gaussian modes

    NASA Astrophysics Data System (ADS)

    Dong, Jun; He, Yu; Bai, Sheng-Chuang; Ueda, Ken-ichi; Kaminskii, Alexander A.

    2016-09-01

    A nanosecond, high peak power, passively Q-switched laser for controllable Hermite-Gaussian (HG) modes has been achieved by manipulating the saturated inversion population inside the gain medium. The stable HG modes are generated in a Cr4+:YAG passively Q-switched Nd:YVO4 microchip laser by applying a tilted pump beam. The asymmetrical saturated inversion population distribution inside the Nd:YVO4 crystal for desirable HG modes is manipulated by choosing the proper pump beam diameter and varying pump power. A HG9,8 mode passively Q-switched Nd:YVO4 microchip laser with average output power of 265 mW has been obtained. Laser pulses with a pulse width of 7.3 ns and peak power of over 1.7 kW working at 21 kHz have been generated in the passively Q-switched Nd:YVO4 microchip laser.

  17. Structure of the Cell Wall of Bacillus stearothermophilus: Mode of Action of a Thermophilic Bacteriophage Lytic Enzyme

    PubMed Central

    Welker, N. E.

    1971-01-01

    The mode of action of a bacteriophage lytic enzyme on cell walls of Bacillus stearothermophilus (NCA 1503-4R) has been investigated. The enzyme is an endopeptidase which catalyzes the hydrolysis of the l-alanyl-d-glutamyl linkage in peptide subunits of the cell wall peptidoglycan. Preliminary studies on the soluble components in lytic cell wall digests indicate that the glycan moiety is composed of alternating glucosamine and muramic acid; one half of the muramic acid residues contain the tripeptide, l-alanyl-d-glutamyldiaminopimelic acid, and the remaining residues contain the tetrapeptide, l-alanyl-d-glutamyldiaminopimeyl-d-alanine. Almost one half of the peptide subunits are involved in cross-linkages of chemotype I. A structure for the cell wall peptidoglycan is proposed in the light of these findings. PMID:4255338

  18. A new 2 Kelvin Superconducting Half-Wave Cavity Cryomodule for PIP-II

    NASA Astrophysics Data System (ADS)

    Conway, Z. A.; Barcikowski, A.; Cherry, G. L.; Fischer, R. L.; Gerbick, S. M.; Jansma, W. G.; Kedzie, M. J.; Kelly, M. P.; Kim, S.-h.; Lebedev, V. A.; MacDonald, S. W. T.; Nicol, T. H.; Ostroumov, P. N.; Reid, T. C.; Shepard, K. W.; White, M. J.

    2015-12-01

    Argonne National Laboratory has developed and is implementing a novel 2 K superconducting cavity cryomodule operating at 162.5 MHz. This cryomodule is designed for the acceleration of 2 mA H-/proton beams from 2.1 to 10 MeV as part of the Fermilab Proton Improvement Project-II (PIP-II). This work is an evolution of techniques recently implemented in two previous heavy-ion accelerator cryomodules now operating at Argonne National Laboratory. The 2 K cryomodule is comprised of 8 half-wave cavities operated in the continuous wave mode with 8 superconducting magnets, one in front of each cavity. All of the solenoids and cavities operate off of a single gravity fed 2 K helium cryogenic system expected to provide up to 50 W of 2 K cooling. Here we review the mechanical design of the cavities and cryomodule which were developed using methods similar to those required in the ASME Boiler and Pressure Vessel Code. This will include an overview of the cryomodule layout, the alignment of the accelerator components via modifications of the cryomodule vacuum vessel and provide a status report on the cryomodule assembly.

  19. Dimensions of global population projections: what do we know about future population trends and structures?

    PubMed Central

    Lutz, Wolfgang; KC, Samir

    2010-01-01

    The total size of the world population is likely to increase from its current 7 billion to 8–10 billion by 2050. This uncertainty is because of unknown future fertility and mortality trends in different parts of the world. But the young age structure of the population and the fact that in much of Africa and Western Asia, fertility is still very high makes an increase by at least one more billion almost certain. Virtually, all the increase will happen in the developing world. For the second half of the century, population stabilization and the onset of a decline are likely. In addition to the future size of the population, its distribution by age, sex, level of educational attainment and place of residence are of specific importance for studying future food security. The paper provides a detailed discussion of different relevant dimensions in population projections and an evaluation of the methods and assumptions used in current global population projections and in particular those produced by the United Nations and by IIASA. PMID:20713384

  20. Half-Scale Starshade

    NASA Image and Video Library

    2016-08-09

    A deployed half-scale starshade with four petals at NASA's Jet Propulsion Laboratory, Pasadena, California, in 2014. The flower-like petals of the starshade are designed to diffract bright starlight away from telescopes seeking the dim light of exoplanets. The starshade was re-designed from earlier models to allow these petals to furl, or wrap around the spacecraft, for launch into space. Each petal is covered in a high-performance plastic film that resembles gold foil. On a starshade ready for launch, the thermal gold foil will only cover the side of the petals facing away from the telescope, with black on the other, so as not to reflect other light sources such as the Earth into its camera. http://photojournal.jpl.nasa.gov/catalog/PIA20904

  1. The Growth of Older Inmate Populations: How Population Aging Explains Rising Age at Admission.

    PubMed

    Luallen, Jeremy; Cutler, Christopher

    2017-09-01

    Older inmates are the fastest growing segment of the prison population; however, the reasons for this are not well understood. One explanation is that the general population is aging, driving prison age distributions to change. For this article, we study the role of population aging in prison growth by investigating how the baby boom phenomenon of post-World War II has contributed to the growth of older inmate populations. We identify the impact of population aging using simulation methods that explain prison growth as the combination of criminal justice processes. Overall, we find evidence that population aging has played a significant role in explaining the growth of older inmate populations, in particular among inmates aged between 50 and 64 years, contributing to as much as half of the observed increase in these groups since 2000. This finding stands in contrast to the notion that population aging has little explanatory power in describing the growth of prison populations and implies that older inmate groups are more sensitive to compositional changes in the general population. We argue that prediction-based modeling of prison growth should more seriously consider the impacts and consequences of demographic shifts among older prisoner populations. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Directional power absorption in helicon plasma sources excited by a half-helix antenna

    NASA Astrophysics Data System (ADS)

    Afsharmanesh, Mohsen; Habibi, Morteza

    2017-10-01

    This paper deals with the investigation of the power absorption in helicon plasma excited through a half-helix antenna driven at 13.56 {{MHz}}. The simulations were carried out by means of a code, HELIC. They were carried out by taking into account different inhomogeneous radial density profiles and for a wide range of plasma densities, from {10}11 {{{cm}}}-3 to {10}13 {{{cm}}}-3. The magnetic field was 200, 400, 600 and 1000 {{G}}. A three-parameter function was used for generating various density profiles with different volume gradients, edge gradients and density widths. The density profile had a large effect on the efficient Trivelpiece-Gould (TG) and helicon mode excitation and antenna coupling to the plasma. The fraction of power deposition via the TG mode was extremely dependent on the plasma density near the plasma boundary. Interestingly, the obtained efficient parallel helicon wavelength was close to the anticipated value for Gaussian radial density profile. Power deposition was considerably asymmetric when the \\tfrac{n}{{B}0} ratio was more than a specific value for a determined density width. The longitudinal power absorption was symmetric at approximately {n}0={10}11 {{{cm}}}-3, irrespective of the magnetic field supposed. The asymmetry became more pronounced when the plasma density was {10}12 {{{cm}}}-3. The ratio of density width to the magnetic field was an important parameter in the power coupling. At high magnetic fields, the maximum of the power absorption was reached at higher plasma density widths. There was at least one combination of the plasma density, magnetic field and density width for which the RF power deposition at both side of the tube reached its maximum value.

  3. 4 × 20 Gbit/s mode division multiplexing over free space using vector modes and a q-plate mode (de)multiplexer

    NASA Astrophysics Data System (ADS)

    Milione, Giovanni; Lavery, Martin P. J.; Huang, Hao; Ren, Yongxiong; Xie, Guodong; Nguyen, Thien An; Karimi, Ebrahim; Marrucci, Lorenzo; Nolan, Daniel A.; Alfano, Robert R.; Willner, Alan E.

    2015-05-01

    Vector modes are spatial modes that have spatially inhomogeneous states of polarization, such as, radial and azimuthal polarization. They can produce smaller spot sizes and stronger longitudinal polarization components upon focusing. As a result, they are used for many applications, including optical trapping and nanoscale imaging. In this work, vector modes are used to increase the information capacity of free space optical communication via the method of optical communication referred to as mode division multiplexing. A mode (de)multiplexer for vector modes based on a liquid crystal technology referred to as a q-plate is introduced. As a proof of principle, using the mode (de)multiplexer four vector modes each carrying a 20 Gbit/s quadrature phase shift keying signal on a single wavelength channel (~1550nm), comprising an aggregate 80 Gbit/s, were transmitted ~1m over the lab table with <-16.4 dB (<2%) mode crosstalk. Bit error rates for all vector modes were measured at the forward error correction threshold with power penalties < 3.41dB.

  4. A second look at the heavy half of the camping market

    Treesearch

    Wilbur R. LaPage; Dale P. Ragain; Dale P. Ragain

    1971-01-01

    A 1968 survey of campers revealed that one-half of the campers did more than three-fourths of all the reported camping. Campers in this heavy half of the camping market were found to differ significantly from light-half campers in their camping motivations, past experience, and investments in camping equipment (LdPage 1969). However, the 1968 survey identified heavy-...

  5. [Application of Multiple Genetic Markers in a Case of Determination of Half Sibling].

    PubMed

    Yang, Xue; Shi, Mei-sen; Yuan, Li; Lu, Di

    2016-02-01

    A case of half sibling was determined with multiple genetic markers, which could be potentially applied for determination of half sibling relationship from same father. Half sibling relationship was detected by 39 autosomal STR genetic markers, 23 Y-chromosomal STR genetic markers and 12 X -chromosomal STR genetic markers among ZHAO -1, ZHAO -2, ZHAO -3, ZHAO -4, and ZHAO-5. According to autosomal STR, Y-STR and X-STR genotyping results, it was determined that ZHAO-4 (alleged half sibling) was unrelated with ZHAO-1 and ZHAO-2; however, ZHAO-3 (alleged half sibling), ZHAO-5 (alleged half sibling) shared same genetic profile with ZHAO-1, and ZHAO-2 from same father. It is reliable to use multiple genetic markers and family gene reconstruction to determine half sibling relationship from same father, but it is difficult to determination by calculating half sibling index with ITO and discriminant functions.

  6. Mathematical models for the reflection coefficients of dielectric half-spaces

    NASA Technical Reports Server (NTRS)

    Evans, D. D.

    1973-01-01

    The reflection coefficients at normal incidence are found for a large class of one-dimensionally inhomogeneous or stratified half-spaces, which contain a homogeneous half-space. The formulation of the problem involves a combination of the classical boundary value technique, and the nonclassical principle of invariant imbedding. Solutions are in closed form and expressible in terms of Bessel functions. All results are given in terms of the ratio of the distance between free space and the homogeneous half-space to the wavelength in vacuo. One special case is that of an arbitrary number of layers lying on a homogeneous half-space where the dielectric constant of each layer has a constant gradient. A number of other special cases, limiting cases, and generalizations are developed including one in which the thickness of the top layer obeys a probability distribution.

  7. Femtosecond pulse inscription of a selective mode filter in large mode area fibers

    NASA Astrophysics Data System (ADS)

    Krämer, Ria G.; Voigtländer, Christian; Freier, Erik; Liem, Andreas; Thomas, Jens U.; Richter, Daniel; Schreiber, Thomas; Tünnermann, Andreas; Nolte, Stefan

    2013-02-01

    We present a selective mode filter inscribed with ultrashort pulses directly into a few mode large mode area (LMA) fiber. The mode filter consists of two refractive index modifications alongside the fiber core in the cladding. The refractive index modifications, which were of approximately the same order of magnitude as the refractive index difference between core and cladding have been inscribed by nonlinear absorption of femtosecond laser pulses (800 nm wavelength, 120 fs pulse duration). If light is guided in the core, it will interact with the inscribed modifications causing modes to be coupled out of the core. In order to characterize the mode filter, we used a femtosecond inscribed fiber Bragg grating (FBG), which acts as a wavelength and therefore mode selective element in the LMA fiber. Since each mode has different Bragg reflection wavelengths, an FBG in a multimode fiber will exhibit multiple Bragg reflection peaks. In our experiments, we first inscribed the FBG using the phase mask scanning technique. Then the mode filter was inscribed. The reflection spectrum of the FBG was measured in situ during the inscription process using a supercontinuum source. The reflectivities of the LP01 and LP11 modes show a dependency on the length of the mode filter. Two stages of the filter were obtained: one, in which the LP11 mode was reduced by 60% and one where the LP01 mode was reduced by 80%. The other mode respectively showed almost no losses. In conclusion, we could selectively filter either the fundamental or higher order modes.

  8. Ping-pong modes and higher-periodicity multipactor

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

    Kishek, R. A.

    Multipactor is a vacuum discharge driven by secondary electron emission. Multiple period multipactors have long been known to exist but have been studied less extensively. In a period-n multipactor, electrons undergo multiple impacts in one rf period, with the synchronous phase alternating periodically between multiple values. A novel resonant form is proposed that combines one- and two-surface impacts within a single period, provided the total transit time is an odd number of rf half-periods and the product of secondary yields exceeds unity. For low fD products, the simplest such mode is shown to significantly increase the upper electric field boundarymore » of the multipacting region and lead to overlap of higher-order bands. The results agree nicely with 3-D particle-in-cell code simulations. An alternative, map-based method is introduced for analyzing higher-periodicity multipactor. Practical implications of the findings are discussed, including consequences for multipactor suppression strategies using a dc magnetic field.« less

  9. Influence of ethacrynic acid on glutathione S-transferase pi transcript and protein half-lives in human colon cancer cells.

    PubMed

    Shen, H; Ranganathan, S; Kuzmich, S; Tew, K D

    1995-10-12

    Ethacrynic acid (EA) is a plant phenolic acid that is both an inhibitor and an inducer of glutathione S-transferase (GST) activity. To determine contributory factors in the increased GST activity caused by EA treatment, human colon carcinoma HT29 cells were compared with a cloned EA-resistant population (HT6-8) maintained in medium containing 72 microM EA. Several factors are involved in the increased expression of GST pi in HT6-8. For example, nuclear run-on experiments showed an approximately 2-fold increase in the rate of transcription of GST pi. In addition, the half-life of GST pi transcript was increased from 4.1 (wild type, HT29, HT4-1) to 8.4 hr. The half-life of GST pi protein was 1-2 hr in HT4-1 cells versus 8-9 hr in HT6-8 cells. When either human ovarian carcinoma cells (SKOV3) or human prostatic carcinoma cells (DU145) were treated with EA, the half-life of the GST pi transcript was also increased. The transcript half-lives of another thiol-metabolism enzyme, gamma-glutamylcysteine synthetase (gamma-GCS), and a phase II detoxification enzyme, dihydrodiol dehydrogenase (DDH), were also increased in HT6-8, SKOV3 and DU145 cells treated with EA. However, the half-lives of transcripts from "housekeeping genes," such as glyceraldehyde 3-phosphate dehydrogenase (G3PDH), beta-actin and beta-tubulin, were not changed in these cell lines following EA. Apparently, a number of coordinated factors are involved in EA-enhanced expression of GST pi and other detoxification enzymes.

  10. Inter-comb synchronization by mode-to-mode locking

    NASA Astrophysics Data System (ADS)

    Chun, Byung Jae; Kim, Young-Jin; Kim, Seung-Woo

    2016-08-01

    Two combs of fiber femtosecond lasers are synchronized through the optical frequency reference created by injection-locking of a diode laser to a single comb mode. Maintaining a mHz-level narrow linewidth, the optical frequency reference permits two combs to be stabilized by mode-to-mode locking with a relative stability of 1.52  ×  10-16 at 10 s with a frequency slip of 2.46 mHz. This inter-comb synchronization can be utilized for applications such as dual-comb spectroscopy or ultra-short pulse synthesis without extra narrow-linewidth lasers.

  11. Design of elliptical-core mode-selective photonic lanterns with six modes for MIMO-free mode division multiplexing systems.

    PubMed

    Sai, Xiaowei; Li, Yan; Yang, Chen; Li, Wei; Qiu, Jifang; Hong, Xiaobin; Zuo, Yong; Guo, Hongxiang; Tong, Weijun; Wu, Jian

    2017-11-01

    Elliptical-core few mode fiber (EC-FMF) is used in a mode division multiplexing (MDM) transmission system to release multiple-input-multiple-output (MIMO) digital-signal-processing, which reduces the cost and the complexity of the receiver. However, EC-FMF does not match with conventional multiplexers/de-multiplexers (MUXs/DeMUXs) such as a photonic lantern, leading to extra mode coupling loss and crosstalk. We design elliptical-core mode-selective photonic lanterns (EC-MSPLs) with six modes, which can match well with EC-FMF in MIMO-free MDM systems. Simulation of the EC-MSPL using the beam propagation method was demonstrated employing a combination of either step-index or graded-index fibers with six different sizes of cores, and the taper transition length of 8 cm or 4 cm. Through numerical simulations and optimizations, both types of photonic lanterns can realize low loss transmission and low crosstalk of below -20.0  dB for all modes.

  12. Predictor variables for half marathon race time in recreational female runners

    PubMed Central

    Knechtle, Beat; Knechtle, Patrizia; Barandun, Ursula; Rosemann, Thomas; Lepers, Romuald

    2011-01-01

    INTRODUCTION: The relationship between skin-fold thickness and running performance has been investigated from 100 m to the marathon distance, except the half marathon distance. OBJECTIVE: To investigate whether anthropometry characteristics or training practices were related to race time in 42 recreational female half marathoners to determine the predictor variables of half-marathon race time and to inform future novice female half marathoners. METHODS: Observational field study at the ‘Half Marathon Basel’ in Switzerland. RESULTS: In the bivariate analysis, body mass (r = 0.60), body mass index (r = 0.48), body fat (r = 0.56), skin-fold at pectoral (r = 0.61), mid-axilla (r = 0.69), triceps (r = 0.49), subscapular (r = 0.61), abdominal (r = 0.59), suprailiac (r = 0.55) medial calf (r = 0.53) site, and speed of the training sessions (r = -0.68) correlated to race time. Mid-axilla skin-fold (p = 0.04) and speed of the training sessions (p = 0.0001) remained significant after multi-variate analysis. Race time in a half marathon might be predicted by the following equation (r2 = 0.71): Race time (min)  =  166.7 + 1.7x (mid-axilla skin-fold, mm) - 6.4x (speed in training, km/h). Running speed during training was related to skin-fold thickness at mid-axilla (r = -0.31), subscapular (r = -0.38), abdominal (r = -0.44), suprailiacal (r = -0.41), the sum of eight skin-folds (r = -0.36) and percent body fat (r = -0.31). CONCLUSION: Anthropometric and training variables were related to half-marathon race time in recreational female runners. Skin-fold thicknesses at various upper body locations were related to training intensity. High running speed in training appears to be important for fast half-marathon race times and may reduce upper body skin-fold thicknesses in recreational female half marathoners. PMID:21484048

  13. Sensitivity to pulse phase duration in cochlear implant listeners: Effects of stimulation mode

    PubMed Central

    Chatterjee, Monita; Kulkarni, Aditya M.

    2014-01-01

    The objective of this study was to investigate charge-integration at threshold by cochlear implant listeners using pulse train stimuli in different stimulation modes (monopolar, bipolar, tripolar). The results partially confirmed and extended the findings of previous studies conducted in animal models showing that charge-integration depends on the stimulation mode. The primary overall finding was that threshold vs pulse phase duration functions had steeper slopes in monopolar mode and shallower slopes in more spatially restricted modes. While the result was clear-cut in eight users of the Cochlear CorporationTM device, the findings with the six user of the Advanced BionicsTM device who participated were less consistent. It is likely that different stimulation modes excite different neuronal populations and/or sites of excitation on the same neuron (e.g., peripheral process vs central axon). These differences may influence not only charge integration but possibly also temporal dynamics at suprathreshold levels and with more speech-relevant stimuli. Given the present interest in focused stimulation modes, these results have implications for cochlear implant speech processor design and protocols used to map acoustic amplitude to electric stimulation parameters. PMID:25096116

  14. Mode-coupling theory

    NASA Astrophysics Data System (ADS)

    Reichman, David R.; Charbonneau, Patrick

    2005-05-01

    In this set of lecture notes we review the mode-coupling theory of the glass transition from several perspectives. First, we derive mode-coupling equations for the description of density fluctuations from microscopic considerations with the use the Mori Zwanzig projection operator technique. We also derive schematic mode-coupling equations of a similar form from a field-theoretic perspective. We review the successes and failures of mode-coupling theory, and discuss recent advances in the applications of the theory.

  15. Robust, low-noise, polarization-maintaining mode-locked Er-fiber laser with a planar lightwave circuit (PLC) device as a multi-functional element.

    PubMed

    Kim, Chur; Kwon, Dohyeon; Kim, Dohyun; Choi, Sun Young; Cha, Sang Jun; Choi, Ki Sun; Yeom, Dong-Il; Rotermund, Fabian; Kim, Jungwon

    2017-04-15

    We demonstrate a new planar lightwave circuit (PLC)-based device, integrated with a 980/1550 wavelength division multiplexer, an evanescent-field-interaction-based saturable absorber, and an output tap coupler, which can be employed as a multi-functional element in mode-locked fiber lasers. Using this multi-functional PLC device, we demonstrate a simple, robust, low-noise, and polarization-maintaining mode-locked Er-fiber laser. The measured full-width at half-maximum bandwidth is 6 nm centered at 1555 nm, corresponding to 217 fs transform-limited pulse duration. The measured RIN and timing jitter are 0.22% [10 Hz-10 MHz] and 6.6 fs [10 kHz-1 MHz], respectively. Our results show that the non-gain section of mode-locked fiber lasers can be easily implemented as a single PLC chip that can be manufactured by a wafer-scale fabrication process. The use of PLC processes in mode-locked lasers has the potential for higher manufacturability of low-cost and robust fiber and waveguide lasers.

  16. Stable isotope turnover and half-life in animal tissues: a literature synthesis.

    PubMed

    Vander Zanden, M Jake; Clayton, Murray K; Moody, Eric K; Solomon, Christopher T; Weidel, Brian C

    2015-01-01

    Stable isotopes of carbon, nitrogen, and sulfur are used as ecological tracers for a variety of applications, such as studies of animal migrations, energy sources, and food web pathways. Yet uncertainty relating to the time period integrated by isotopic measurement of animal tissues can confound the interpretation of isotopic data. There have been a large number of experimental isotopic diet shift studies aimed at quantifying animal tissue isotopic turnover rate λ (%·day(-1), often expressed as isotopic half-life, ln(2)/λ, days). Yet no studies have evaluated or summarized the many individual half-life estimates in an effort to both seek broad-scale patterns and characterize the degree of variability. Here, we collect previously published half-life estimates, examine how half-life is related to body size, and test for tissue- and taxa-varying allometric relationships. Half-life generally increases with animal body mass, and is longer in muscle and blood compared to plasma and internal organs. Half-life was longest in ecotherms, followed by mammals, and finally birds. For ectotherms, different taxa-tissue combinations had similar allometric slopes that generally matched predictions of metabolic theory. Half-life for ectotherms can be approximated as: ln (half-life) = 0.22*ln (body mass) + group-specific intercept; n = 261, p<0.0001, r2 = 0.63. For endothermic groups, relationships with body mass were weak and model slopes and intercepts were heterogeneous. While isotopic half-life can be approximated using simple allometric relationships for some taxa and tissue types, there is also a high degree of unexplained variation in our models. Our study highlights several strong and general patterns, though accurate prediction of isotopic half-life from readily available variables such as animal body mass remains elusive.

  17. Systematics of Scissors Mode in Gd Nuclei from Experiments with the DANCE Detector

    NASA Astrophysics Data System (ADS)

    Kroll, J.; Agvaanluvsan, U.; Baramsai, B.; Becker, J. A.; Bečvář, F.; Bredeweg, T. A.; Chyzh, A.; Couture, A.; Dashdorj, D.; Haight, R. C.; Jandel, M.; Keksis, A. L.; Krtička, M.; Mitchell, G. E.; O'Donnell, J. M.; Parker, W.; Rundberg, R. S.; Ullmann, J. L.; Valenta, S.; Vieira, D. J.; Walker, C. L.; Wilhelmy, J. B.; Wouters, J. M.; Wu, C. Y.

    2014-05-01

    Multi-step cascade γ-ray spectra from neutron capture at isolated resonances of 152,154-158Gd nuclei were measured at the LANSCE/DANCE time-of-flight facility in Los Alamos National Laboratory. The main objective of these experiments was to obtain new information on photon strength functions with emphasis on the role of the M1 scissors mode vibration. An analysis of the data obtained shows that the scissors mode plays a significant role in the ground state transitions, as well as in the transitions populating all excited states of the studied nuclei. The estimates of the scissors mode strength indicate that for 157,159Gd this strength is significantly higher than in neighboring even-even nuclei 156,158Gd. The results are compared with the (γ,γ‧) data for the ground-state scissors mode and the results from 3He-induced reactions.

  18. Rayleigh wave effects in an elastic half-space.

    NASA Technical Reports Server (NTRS)

    Aggarwal, H. R.

    1972-01-01

    Consideration of Rayleigh wave effects in a homogeneous isotropic linearly elastic half-space subject to an impulsive uniform disk pressure loading. An approximate formula is obtained for the Rayleigh wave effects. It is shown that the Rayleigh waves near the center of loading arise from the portion of the dilatational and shear waves moving toward the axis, after they originate at the edge of the load disk. A study is made of the vertical displacement due to Rayleigh waves at points on the axis near the surface of the elastic half-space.

  19. Radiohalogenated half-antibodies and maleimide intermediate therefor

    DOEpatents

    Kassis, Amin I.; Khawli, Leslie A.

    1991-01-01

    N-(m-radiohalophenyl) maleimide can be conjugated with a reduced antibody having a mercapto group to provide a radiolabelled half-antibody having immunological specific binding characteristics of whole antibody.

  20. Population projections for three counties in Zhejiang Province.

    PubMed

    Zhuang, B; Huang, X

    1983-01-01

    Using population numbers and deaths in each age group in Yayao, Jiangshan, and Huangyan counties, China, in 1978, the authors analyze current population dynamics and project population trends for the next 20-60 years. The total population of the 3 counties is 2,314,566, with 33.2% 0-14 years old and 5.7% over 65 years old. The dependency ratio is 63.7%. 24.16% of the women are of childbearing age, 15-49 years old. The birth rate averages 15.39% and the mortality rate is 5.91%. Life expectancy is 68.94 for males and 71.94 for females. Males account for 51.6% of the population and females 48.4%, primarily due to the preferential treatment given to male babies. 3 constrictions in the age pyramid reflect conditions caused by the Japanese invasion of 1941-1945, economic policy blunders during the Great Leap Forward and natural disasters, and, most recently, the family planning program. The recent 1 child family policy aims to limit China's total population to 1.2 billion by the year 2000. Achieving this goal requires careful population planning based on actual local conditions. 3 forecasts--based on different combinations of 1 and 2 child families--estimate total birth rates of 1.46, 1.184, and 1.925. These assumptions produce natural increase rates of 5.66%, 7.83%, and 10.64%. All 3 forecasts produce an aging population, but the dependency ratio decreases. China's population policy must be based on the fact that the current population is 1 billion, 800 million of whom are peasants, and that China has too little arable land and is economically undeveloped. The authors consider forecast 1--in which couples have 2 children each from 1981-1985 and half have 1 and half have 2 child families from 1986-2000--the most desirable because 1) it will be acceptable to the peasant population, 2) it maintains a large labor force, 3) it produces a stable age pyramid, and 4) it remains a reasonable possibility.

  1. Cumulants, free cumulants and half-shuffles

    PubMed Central

    Ebrahimi-Fard, Kurusch; Patras, Frédéric

    2015-01-01

    Free cumulants were introduced as the proper analogue of classical cumulants in the theory of free probability. There is a mix of similarities and differences, when one considers the two families of cumulants. Whereas the combinatorics of classical cumulants is well expressed in terms of set partitions, that of free cumulants is described and often introduced in terms of non-crossing set partitions. The formal series approach to classical and free cumulants also largely differs. The purpose of this study is to put forward a different approach to these phenomena. Namely, we show that cumulants, whether classical or free, can be understood in terms of the algebra and combinatorics underlying commutative as well as non-commutative (half-)shuffles and (half-) unshuffles. As a corollary, cumulants and free cumulants can be characterized through linear fixed point equations. We study the exponential solutions of these linear fixed point equations, which display well the commutative, respectively non-commutative, character of classical and free cumulants. PMID:27547078

  2. Multiple Stellar Populations in Star Clusters

    NASA Astrophysics Data System (ADS)

    Piotto, G.

    2013-09-01

    For half a century it had been astronomical dogma that a globular cluster (GC) consists of stars born at the same time out of the same material, and this doctrine has borne rich fruits. In recent years, high resolution spectroscopy and high precision photometry (from space and ground-based observations) have shattered this paradigm, and the study of GC populations has acquired a new life that is now moving it in new directions. Evidence of multiple stellar populations have been identified in the color-magnitude diagrams of several Galactic and Magellanic Cloud GCs where they had never been imagined before.

  3. Comparison of two modes of delivery of an exercise prescription scheme.

    PubMed

    Foley, Louise; Maddison, Ralph; Jones, Zanta; Brown, Paul; Davys, Anne

    2011-07-08

    Green Prescription (GRx) referrals from health professionals have been shown to be effective for increasing the physical activity levels of patients. Little is known about which methods of delivering the programme represents the best value for money. The purpose of this paper was to compare the cost and outcomes of two modes of delivery of a GRx programme. One mode offered phone support involving monthly telephone calls over a 3-4 month period to encourage physical activity participation. A second mode offered community support via weekly face-to-face support group meetings in which physical activities were offered. The evaluation involved staff interviews, patient interviews and analysis of GRx records for the 2007 calendar year. There was a large rate of drop-out (68%) from GRx referral to registration. For those who registered, there was a clear preference for community support, and engagement of Maori and Pacific peoples was higher in this mode of delivery. The proportion (but not absolute number) of people who successfully completed their mode of delivery was higher with phone support. However, participants in community support self-reported a significantly greater number of days of exercise per week than those in phone support. The total expected cost per person for phone support was $102.07 and $108.15 for community support. A greater proportion of participants in community support were very satisfied overall with their mode of delivery. The two modes were comparable in cost and outcomes, though there was greater penetration of target ethnic populations in community support. Providing a choice of GRx mode of delivery allows participants to choose based on their personal and cultural needs.

  4. Comparing data quality and cost from three modes of on-board transit passenger surveys.

    DOT National Transportation Integrated Search

    2015-06-01

    This report presents the findings from a research project investigating the relative data quality and administration costs for three : different modes of surveying bus passengers that produce results generalizable to the full passenger population. Th...

  5. Altered Functional Connectivity of the Default Mode Network in Low-Empathy Subjects

    PubMed Central

    Kim, Seung Jun; Kim, Sung-Eun; Kim, Hyo Eun; Han, Kiwan; Jeong, Bumseok; Kim, Jae-Jin; Namkoong, Kee

    2017-01-01

    Empathy is the ability to identify with or make a vicariously experience of another person's feelings or thoughts based on memory and/or self-referential mental simulation. The default mode network in particular is related to self-referential empathy. In order to elucidate the possible neural mechanisms underlying empathy, we investigated the functional connectivity of the default mode network in subjects from a general population. Resting state functional magnetic resonance imaging data were acquired from 19 low-empathy subjects and 18 medium-empathy subjects. An independent component analysis was used to identify the default mode network, and differences in functional connectivity strength were compared between the two groups. The low-empathy group showed lower functional connectivity of the medial prefrontal cortex and anterior cingulate cortex (Brodmann areas 9 and 32) within the default mode network, compared to the medium-empathy group. The results of the present study suggest that empathy is related to functional connectivity of the medial prefrontal cortex/anterior cingulate cortex within the default mode network. Functional decreases in connectivity among low-empathy subjects may reflect an impairment of self-referential mental simulation. PMID:28792155

  6. Altered Functional Connectivity of the Default Mode Network in Low-Empathy Subjects.

    PubMed

    Kim, Seung Jun; Kim, Sung Eun; Kim, Hyo Eun; Han, Kiwan; Jeong, Bumseok; Kim, Jae Jin; Namkoong, Kee; Kim, Ji Woong

    2017-09-01

    Empathy is the ability to identify with or make a vicariously experience of another person's feelings or thoughts based on memory and/or self-referential mental simulation. The default mode network in particular is related to self-referential empathy. In order to elucidate the possible neural mechanisms underlying empathy, we investigated the functional connectivity of the default mode network in subjects from a general population. Resting state functional magnetic resonance imaging data were acquired from 19 low-empathy subjects and 18 medium-empathy subjects. An independent component analysis was used to identify the default mode network, and differences in functional connectivity strength were compared between the two groups. The low-empathy group showed lower functional connectivity of the medial prefrontal cortex and anterior cingulate cortex (Brodmann areas 9 and 32) within the default mode network, compared to the medium-empathy group. The results of the present study suggest that empathy is related to functional connectivity of the medial prefrontal cortex/anterior cingulate cortex within the default mode network. Functional decreases in connectivity among low-empathy subjects may reflect an impairment of self-referential mental simulation. © Copyright: Yonsei University College of Medicine 2017.

  7. 1.5  kW ytterbium-doped single-transverse-mode, linearly polarized monolithic fiber master oscillator power amplifier.

    PubMed

    Huang, Long; Ma, Pengfei; Tao, Rumao; Shi, Chen; Wang, Xiaolin; Zhou, Pu

    2015-04-01

    A linearly polarized monolithic fiber laser based on a master oscillator power amplifier structure with a master oscillator and a one-stage power amplifier is reported. We design a homemade oscillator based on the theory that, in the coiled gain fiber, the higher modes and the polarized mode of the fundamental mode along the fast axis are suppressed effectively because of their obviously higher bend loss than that of the polarized mode of the fundamental mode along the slow axis. The oscillator operates at 1080 nm, launching a 30 W seed laser with a high polarization extinction ratio of 19 dB into the power amplifier via a mode field adapter. The power amplifier utilizes Yb-doped polarization-maintaining fiber of 20/400  μm, which produces nearly diffraction-limited output power of about 1.5 kW with an optical-optical efficiency of 81.5% and a polarization extinction ratio of 13.8 dB. Both the M(x)² factor and the M(y)² factor of the collimated beam are measured to be about 1.2. The spectral width of the output power is broadened approximately linearly, and the full width at half maximum of the spectrum at the maximum output power is about 5.8 nm. It is known as the highest linearly polarized output power to the best of our knowledge.

  8. SIBLING CONFLICTS IN FULL- AND HALF-SIBLING HOUSEHOLDS IN THE UK.

    PubMed

    Tanskanen, Antti O; Danielsbacka, Mirkka; Jokela, Markus; Rotkirch, Anna

    2017-01-01

    Sibling relations are by nature ambivalent with high levels of both altruistic helping and competition. Higher relatedness is often assumed to reduce the occurrence of conflicts between siblings, but evidence of this has been scarce and mixed. Siblings typically compete over resources and parental attention, and parental constellations vary with sibship types. Since full-siblings compete over the same two biological parents, while half-siblings have only one shared biological parent and often a higher number of parents overall, it is hypothesized that conflicts are more common between full- than half-siblings. This study tested this assumption using the British Millennium Cohort Study (n=7527 children at age 11). Conflicts were measured as children's reports of how much siblings picked on and hurt each other. Households with full-siblings only, maternal half-siblings only, and both full- and maternal half-siblings were compared. The results show that children who were living with only their full-siblings were more likely to experience sibling conflicts compared with children living with their maternal half-siblings only. This was the case also after controlling for several potentially confounding variables. The results suggest that differential access to parental resources of available biological and step-parents may explain the higher amount of sibling conflict between full- compared with maternal half-siblings.

  9. Particle simulations of mode conversion between slow mode and fast mode in lower hybrid range of frequencies

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

    Jia, Guozhang; Xiang, Nong; Huang, Yueheng

    2016-01-15

    The propagation and mode conversion of lower hybrid waves in an inhomogeneous plasma are investigated by using the nonlinear δf algorithm in a two-dimensional particle-in-cell simulation code based on the gyrokinetic electron and fully kinetic ion (GeFi) scheme [Lin et al., Plasma Phys. Controlled Fusion 47, 657 (2005)]. The characteristics of the simulated waves, such as wavelength, frequency, phase, and group velocities, agree well with the linear theoretical analysis. It is shown that a significant reflection component emerges in the conversion process between the slow mode and the fast mode when the scale length of the density variation is comparablemore » to the local wavelength. The dependences of the reflection coefficient on the scale length of the density variation are compared with the results based on the linear full wave model for cold plasmas. It is indicated that the mode conversion for the waves with a frequency of 2.45 GHz (ω ∼ 3ω{sub LH}, where ω{sub LH} represents the lower hybrid resonance) and within Tokamak relevant amplitudes can be well described in the linear scheme. As the frequency decreases, the modification due to the nonlinear term becomes important. For the low-frequency waves (ω ∼ 1.3ω{sub LH}), the generations of the high harmonic modes and sidebands through nonlinear mode-mode coupling provide new power channels and thus could reduce the reflection significantly.« less

  10. Accurate mode characterization of two-mode optical fibers by in-fiber acousto-optics.

    PubMed

    Alcusa-Sáez, E; Díez, A; Andrés, M V

    2016-03-07

    Acousto-optic interaction in optical fibers is exploited for the accurate and broadband characterization of two-mode optical fibers. Coupling between LP 01 and LP 1m modes is produced in a broadband wavelength range. Difference in effective indices, group indices, and chromatic dispersions between the guided modes, are obtained from experimental measurements. Additionally, we show that the technique is suitable to investigate the fine modes structure of LP modes, and some other intriguing features related with modes' cut-off.

  11. Transient analysis mode participation for modal survey target mode selection using MSC/NASTRAN DMAP

    NASA Technical Reports Server (NTRS)

    Barnett, Alan R.; Ibrahim, Omar M.; Sullivan, Timothy L.; Goodnight, Thomas W.

    1994-01-01

    Many methods have been developed to aid analysts in identifying component modes which contribute significantly to component responses. These modes, typically targeted for dynamic model correlation via a modal survey, are known as target modes. Most methods used to identify target modes are based on component global dynamic behavior. It is sometimes unclear if these methods identify all modes contributing to responses important to the analyst. These responses are usually those in areas of hardware design concerns. One method used to check the completeness of target mode sets and identify modes contributing significantly to important component responses is mode participation. With this method, the participation of component modes in dynamic responses is quantified. Those modes which have high participation are likely modal survey target modes. Mode participation is most beneficial when it is used with responses from analyses simulating actual flight events. For spacecraft, these responses are generated via a structural dynamic coupled loads analysis. Using MSC/NASTRAN DMAP, a method has been developed for calculating mode participation based on transient coupled loads analysis results. The algorithm has been implemented to be compatible with an existing coupled loads methodology and has been used successfully to develop a set of modal survey target modes.

  12. Designing of peptides with desired half-life in intestine-like environment.

    PubMed

    Sharma, Arun; Singla, Deepak; Rashid, Mamoon; Raghava, Gajendra Pal Singh

    2014-08-20

    In past, a number of peptides have been reported to possess highly diverse properties ranging from cell penetrating, tumor homing, anticancer, anti-hypertensive, antiviral to antimicrobials. Owing to their excellent specificity, low-toxicity, rich chemical diversity and availability from natural sources, FDA has successfully approved a number of peptide-based drugs and several are in various stages of drug development. Though peptides are proven good drug candidates, their usage is still hindered mainly because of their high susceptibility towards proteases degradation. We have developed an in silico method to predict the half-life of peptides in intestine-like environment and to design better peptides having optimized physicochemical properties and half-life. In this study, we have used 10mer (HL10) and 16mer (HL16) peptides dataset to develop prediction models for peptide half-life in intestine-like environment. First, SVM based models were developed on HL10 dataset which achieved maximum correlation R/R2 of 0.57/0.32, 0.68/0.46, and 0.69/0.47 using amino acid, dipeptide and tripeptide composition, respectively. Secondly, models developed on HL16 dataset showed maximum R/R2 of 0.91/0.82, 0.90/0.39, and 0.90/0.31 using amino acid, dipeptide and tripeptide composition, respectively. Furthermore, models that were developed on selected features, achieved a correlation (R) of 0.70 and 0.98 on HL10 and HL16 dataset, respectively. Preliminary analysis suggests the role of charged residue and amino acid size in peptide half-life/stability. Based on above models, we have developed a web server named HLP (Half Life Prediction), for predicting and designing peptides with desired half-life. The web server provides three facilities; i) half-life prediction, ii) physicochemical properties calculation and iii) designing mutant peptides. In summary, this study describes a web server 'HLP' that has been developed for assisting scientific community for predicting intestinal half

  13. Polariton condensation, superradiance and difference combination parametric resonance in mode-locked laser

    NASA Astrophysics Data System (ADS)

    Bagayev, S. N.; Arkhipov, R. M.; Arkhipov, M. V.; Egorov, V. S.; Chekhonin, I. A.; Chekhonin, M. A.

    2017-11-01

    The generation of the ring mode-locked laser containing resonant absorption medium in the cavity was investigated. It is shown that near the strong resonant absorption lines a condensation of polaritons arises. Intensive radiation looks like as superradiance in a medium without population inversion. We studied theoretically the microscopic mechanism of these phenomena. It was shown that in this system in absorbing medium a strong self-induced difference combination parametric resonance exists. Superradiance on polaritonic modes in the absorbing medium are due to the emergence of light-induced resonant polarization as a result of fast periodic nonadiabatic quantum jumps in the absorber.

  14. Four Years of North Pacific Mode Water Evolution: A Fukushima Tracer Perspective

    NASA Astrophysics Data System (ADS)

    Macdonald, Alison M.; Yoshida, Sachiko; Pike, Steven; Buesseler, Ken O.; Rypina, Irina I.; Jayne, Steven

    2017-04-01

    Here we presents the results of a investigation which uses the tracer information provided by the 2011 direct ocean release of radio-isotopes, (137Cs, 30-year half-life and 134Cs, 2-year half-life) from the Fukushima Daiichi nuclear power plant to better understand the pathways, mixing and transport of water in the North Pacific Ocean. The main focus is the analysis of cesium observations obtained from the spring 2015 CLIVAR/GO-SHIP occupation of the P16N line in the eastern North Pacific. Nearly four hundred 20 L radionuclide samples were obtained on this cruise between 29 April and 26 June 2015 covering the 152°W line from 3°N to the Alaskan Shelf off Kodiak (56.4°N), crossing the Alaska Gyre at 55°N and making a short (200 nm) line extending from the outer edge of U.S. EEZ coming into Seattle, just to the south of the Canadian border and Line-P. Samples include both profiles from the surface to 1000 m and surface/subsurface pairs that provide an average 1° latitude spacing along 152°W. A clear Fukushima signal is apparent from the surface down to 400 m. The core signal lies at between 0-200 m at about 40°N where Subtropical Mode Water density water outcrops. The densest waters with Fukushima isotopes lie at 440 m in the bottom density range of Dense-Central Mode Water. There is a weak, but detectable signal in the Alaska Current to the north off both Kodiak and Sitka. The deepest detectable 137Cs (weapon's testing) signals are found at and to the north of 45°N at 900-1000 m. There is detectable, background level 137Cs as far south as 3°N, but as of spring 2015 the southernmost 134C signal was found above 200 m at 30°N. This horizontal and vertical pattern of Fukushima radionuclides traces the path of mode waters from their formation regions in the western North Pacific to their outcrop in eastern basin over the four years since their release.

  15. Intrinsically disordered segments and the evolution of protein half-life

    NASA Astrophysics Data System (ADS)

    Babu, M.

    2013-03-01

    Precise turnover of proteins is essential for cellular homeostasis and is primarily mediated by the proteasome. Thus, a fundamental question is: What features make a protein an efficient substrate for degradation? Here I will present results that proteins with a long terminal disordered segment or internal disordered segments have a significantly shorter half-life in yeast. This relationship appears to be evolutionarily conserved in mouse and human. Furthermore, upon gene duplication, divergence in the length of terminal disorder or variation in the number of internal disordered segments results in significant alteration of the half-life of yeast paralogs. Many proteins that exhibit such changes participate in signaling, where altered protein half-life will likely influence their activity. We suggest that variation in the length and number of disordered segments could serve as a remarkably simple means to evolve protein half-life and may serve as an underappreciated source of genetic variation with important phenotypic consequences. MMB acknowledges the Medical Research Council for funding his research program.

  16. Power converter for raindrop energy harvesting application: Half-wave rectifier

    NASA Astrophysics Data System (ADS)

    Izrin, Izhab Muhammad; Dahari, Zuraini

    2017-10-01

    Harvesting raindrop energy by capturing vibration from impact of raindrop have been explored extensively. Basically, raindrop energy is generated by converting the kinetic energy of raindrop into electrical energy by using polyvinylidene fluoride (PVDF) piezoelectric. In this paper, a power converter using half-wave rectifier for raindrop harvesting energy application is designed and proposed to convert damping alternating current (AC) generated by PVDF into direct current (DC). This research presents parameter analysis of raindrop simulation used in the experiment and resistive load effect on half-wave rectifier converter. The experiment is conducted by using artificial raindrop from the height of 1.3 m to simulate the effect of different resistive load on the output of half-wave rectifier converter. The results of the 0.68 MΩ resistive load showed the best performance of the half-wave rectifier converter used in raindrop harvesting energy system, which generated 3.18 Vaverage. The peak instantaneous output generated from this experiment is 15.36 µW.

  17. 77 FR 9850 - Safety Zone; 2012 Mavericks Invitational, Half Moon Bay, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-21

    ...-AA08 Safety Zone; 2012 Mavericks Invitational, Half Moon Bay, CA AGENCY: Coast Guard, DHS. ACTION... Pillar Point in the navigable waters of Half Moon Bay, California. The regulation will temporarily... the navigable waters of Half Moon Bay in vicinity of Pillar Point. The Coast Guard will enforce a...

  18. Radiohalogenated half-antibodies and maleimide intermediate therefor

    DOEpatents

    Kassis, A.I.; Khawli, L.A.

    1991-02-19

    N-(m-radiohalophenyl) maleimide can be conjugated with a reduced antibody having a mercapto group to provide a radiolabeled half-antibody having immunological specific binding characteristics of whole antibody. No Drawings

  19. A half-mile walk decreases visual acuity in active older people.

    PubMed

    De Oliveira Filho, Ciro Winckler; Dias, Roges Ghidini; Tavares, Graziela Morgana Silva; Santos, Gilmar Moraes; Mazo, Giovana Zarpellon

    2010-06-01

    The influence of a half-mile walk on the visual acuity of older people who engaged in physical activity was examined. 91 elderly people of both sexes (20 men, 71 women; M age = 69 yr., SD = 6) participated. All were assessed before and after the half-mile walking test for visual acuity (Snellen Optotype Scale) and heart rate. The data indicated a significant decrease in visual acuity as a result of the half-mile test.

  20. SU-D-207-07: Implementation of Full/half Bowtie Filter Model in a Commercial Treatment Planning System for Kilovoltage X-Ray Imaging Dose Estimation

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

    Kim, S; Alaei, P

    2015-06-15

    Purpose: To implement full/half bowtie filter models in a commercial treatment planning system (TPS) to calculate kilovoltage (kV) x-ray imaging dose of Varian On-Board Imager (OBI) cone beam CT (CBCT) system. Methods: Full/half bowtie filters of Varian OBI were created as compensator models in Pinnacle TPS (version 9.6) using Matlab software (version 2011a). The profiles of both bowtie filters were acquired from the manufacturer, imported into the Matlab system and hard coded in binary file format. A Pinnacle script was written to import each bowtie filter data into a Pinnacle treatment plan as a compensator. A kV x-ray beam modelmore » without including the compensator model was commissioned per each bowtie filter setting based on percent depth dose and lateral profile data acquired from Monte Carlo simulations. To validate the bowtie filter models, a rectangular water phantom was generated in the planning system and an anterior/posterior beam with each bowtie filter was created. Using the Pinnacle script, each bowtie filter compensator was added to the treatment plan. Lateral profile at the depth of 3cm and percent depth dose were measured using an ion chamber and compared with the data extracted from the treatment plans. Results: The kV x-ray beams for both full and half bowtie filter have been modeled in a commercial TPS. The difference of lateral and depth dose profiles between dose calculations and ion chamber measurements were within 6%. Conclusion: Both full/half bowtie filter models provide reasonable results in kV x-ray dose calculations in the water phantom. This study demonstrates the possibility of using a model-based treatment planning system to calculate the kV imaging dose for both full and half bowtie filter modes. Further study is to be performed to evaluate the models in clinical situations.« less

  1. Observation of 67 keV x-rays with a scintillation detector using proportional-mode silicon avalanche photodiode

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

    Inoue, Keisuke; Kishimoto, Shunji, E-mail: syunji.kishimoto@kek.jp; Inst. of Materials Structure Science, KEK, 1-1 Oho, Tsukuba, Ibaraki 305-0801

    2016-07-27

    We developed a scintillation X-ray detector using a proportional-mode silicon avalanche photodiode (Si-APD). We report a prototype detector using a lead-loaded plastic scintillator mounted on a proportional-mode Si-APD (active area size: 3 mm in diameter), which is operated at a low temperature. Using 67.41 keV X-rays, we could measure pulse-height spectra of scintillation light with a charge-sensitive preamplifier at 20, 0, and −35°C. Time spectra of the X-ray bunch structure were successfully recorded using a wideband and 60-dB-gain amplifier in hybrid-mode operation of the Photon Factory ring. We obtained a better time resolution of 0.51 ns (full width at half-maximum)more » for the single-bunch X-ray peak at −35°C. We were also able to observe a linear response of the scintillation pulses up to 8 Mcps for input photon rates up to 1.4 × 10{sup 8} photons/s.« less

  2. Determination of intrinsic mode and linear mode coupling in solar microwave bursts

    NASA Astrophysics Data System (ADS)

    Huang, Guangli; Song, Qiwu; Li, Jianping

    2013-05-01

    An explicit equation of the propagational angle of microwave emission between the line-of-sight and the local magnetic field is newly derived based on the approximated formulae of nonthermal gyrosynchrotron emission (Dulk and Marsh in Astrophys. J. 259, 350, 1982). The existence of the solution of propagational angle is clearly shown under a series of typical parameters in solar microwave observations. It could be used to determine the intrinsic mode and linear mode coupling in solar microwave bursts by three steps. (1) The mode coupling may happen only when the angle approximately equals to 90 degrees, i.e., when the emission propagates through the quasi-transverse region (Cohen in Astrophys. J. 131, 664, 1960). (2) The inversion of polarization sense due to the weakly mode coupling takes place only when the transition frequency defined by Cohen (1960) is larger than the frequency of microwave emission, and an observable criterion of the weakly mode coupling in flaring loops was indicated by the same polarization sense in the two footpoints of a flaring loop (Melrose and Robinson in Proc. Astron. Soc. Aust. 11, 16, 1994). (3) Finally, the intrinsic mode of microwave emission is determined by the observed polarization and the calculated direction of local magnetic field according to the general plasma dispersion relation, together with the mode coupling process. However, a 180-degree ambiguity still exists in the direction of longitudinal magnetic field, to produce an uncertainty of the intrinsic mode. One example is selected to check the feasibility of the method in the 2001 September 25 event with a loop-like structure nearby the central meridian passage observed by Nobeyama Radio Heliograph and Polarimeters. The calculated angle in one footpoint (FP) varied around 90∘ in two time intervals of the maximum phase, which gives a direct evidence of the emission propagating through a quasi-transverse region where the linear mode coupling took place, while, the angle

  3. Dual-Mode Combustor

    NASA Technical Reports Server (NTRS)

    Trefny, Charles J (Inventor); Dippold, Vance F (Inventor)

    2013-01-01

    A new dual-mode ramjet combustor used for operation over a wide flight Mach number range is described. Subsonic combustion mode is usable to lower flight Mach numbers than current dual-mode scramjets. High speed mode is characterized by supersonic combustion in a free-jet that traverses the subsonic combustion chamber to a variable nozzle throat. Although a variable combustor exit aperture is required, the need for fuel staging to accommodate the combustion process is eliminated. Local heating from shock-boundary-layer interactions on combustor walls is also eliminated.

  4. Prospective high thermoelectric performance of the heavily p -doped half-Heusler compound CoVSn

    DOE PAGES

    Shi, Hongliang; Ming, Wenmei; Parker, David S.; ...

    2017-05-11

    The electronic structure and transport properties of the half-Heusler compound CoVSn are studied in this paper systematically by combining first-principles electronic structure calculations and Boltzmann transport theory. The band structure at the valence-band edge is complex with multiple maxima derived from hybridized transition element d states. The result is a calculated thermopower larger than 200 μV /Κ within a wide range of doping concentrations and temperatures for heavily doped p-type CoVSn. The thermoelectric properties additionally benefit from the corrugated shapes of the hole pockets in our calculated isoenergy surfaces. Our calculated power factor S 2σ/τ (with respect to an averagemore » unknown scattering time) of CoVSn is comparable to that of FeNbSb. A smaller lattice thermal conductivity can be expected from the smaller group velocities of acoustical modes compared to FeNbSb. Finally, overall, good thermoelectric performance for CoVSn can be expected by considering the electronic transport and lattice thermal conductivity.« less

  5. Prospective high thermoelectric performance of the heavily p -doped half-Heusler compound CoVSn

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

    Shi, Hongliang; Ming, Wenmei; Parker, David S.

    The electronic structure and transport properties of the half-Heusler compound CoVSn are studied in this paper systematically by combining first-principles electronic structure calculations and Boltzmann transport theory. The band structure at the valence-band edge is complex with multiple maxima derived from hybridized transition element d states. The result is a calculated thermopower larger than 200 μV /Κ within a wide range of doping concentrations and temperatures for heavily doped p-type CoVSn. The thermoelectric properties additionally benefit from the corrugated shapes of the hole pockets in our calculated isoenergy surfaces. Our calculated power factor S 2σ/τ (with respect to an averagemore » unknown scattering time) of CoVSn is comparable to that of FeNbSb. A smaller lattice thermal conductivity can be expected from the smaller group velocities of acoustical modes compared to FeNbSb. Finally, overall, good thermoelectric performance for CoVSn can be expected by considering the electronic transport and lattice thermal conductivity.« less

  6. Penetration of diesel exhaust particles through commercially available dust half masks.

    PubMed

    Penconek, Agata; Drążyk, Paulina; Moskal, Arkadiusz

    2013-04-01

    Half masks are certified by the competent, national institutions--National Institute for Occupational Safety and Health (NIOSH) in the USA and the respective European national institutions applying common European regulations. However, certification testing is conducted with particles of NaCl, paraffin oil, or dioctyl phthalate (DOP) and at the constant flow rate, whereas particles commonly found in workplaces may differ in size, shape, and morphology from these particles. Therefore, the aim of this study was to investigate filtration efficiency of commercially available filtering facepiece half masks under the condition of exposure to diesel fumes. In this study, we focused on the particulate phase [diesel exhaust particles (DEP)] of three (petroleum diesel, ecodiesel, and biodiesel) diesel fuel combustion types. Two types of European standard-certified half masks, FFP2 and FFP - Filtering Facepiece, and three types of popular diesel fuels were tested. The study showed that the filtration efficiencies for each examined half mask and for each of diesel exhaust fumes were lower than the minimum filtration efficiency required for the standard test aerosols by the European standards. For FFP2 and FFP3 particulate half masks, standard minimum filtration efficiency is 94 and 99%, respectively, whereas 84-89% of mass of DEP from various fuels were filtered by the tested FFP2 and only 75-86% by the FFP3. The study indicated that DEP is more penetrating for these filters than the standard salt or paraffin oil test aerosols. The study also showed that the most penetrating DEP are probably in the 30- to 300-nm size range, regardless of the fuel type and the half-mask model. Finally, the pressure drops across both half masks during the 80-min tests remained below an acceptable maximum of breathing resistance-regardless of the fuel types. The respiratory system, during 40-min test exposures, may be exposed to 12-16mg of DEP if a FFP2 or FFP3 particulate half mask is used. To

  7. Half-Heusler Alloys as Promising Thermoelectric Materials

    NASA Astrophysics Data System (ADS)

    Page, Alexander A.

    This thesis describes Ph.D. research on the half-Heusler class of thermoelectric materials. Half-Heusler alloys are a versatile class of materials that have been studied for use in photovoltaics, phase change memory, and thermoelectric power generation. With respect to thermoelectric power generation, new approaches were recently developed in order to improve the thermoelectric figure of merit, ZT, of half-Heusler alloys. Two of the strategies discussed in this work are adding excess Ni within MNiSn (M = Ti, Zr, or Hf) compounds to form full-Heusler nanostructures and using isoelectronic substitution of Ti, Zr, and Hf in MNiSn compounds to create microscale grain boundaries. This work uses computational simulations based on density functional theory, combined with the cluster expansion method, to predict the stable phases of pseudo-binary and pseudo-ternary composition systems. Statistical mechanics methods were used to calculate temperature-composition phase diagrams that relate the equilibrium phases. It is shown that full-Heusler nanostructures are predicted to remain stable even at high temperatures, and the microscale grain boundaries observed in (Ti,Zr,Hf)NiSn materials are found to be thermodynamically unstable at equilibrium. A new strategy of combining MNiSn materials with ZrNiPb has also recently emerged, and theoretical and experimental work show that a solid solution of the two materials is stable.

  8. Dependence of L-mode confinement on the electron cyclotron power deposition profile in the TCV tokamak

    NASA Astrophysics Data System (ADS)

    Kirneva, N. A.; Razumova, K. A.; Pochelon, A.; Behn, R.; Coda, S.; Curchod, L.; Duval, B. P.; Goodman, T. P.; Labit, B.; Karpushov, A. N.; Rancic, M.; Sauter, O.; Silva, M.; TCV Team

    2012-01-01

    Scenarios with different electron cyclotron heating power profile distributions and widths were compared for the first time in experiments on the Tokamak à Configuration Variable (TCV). The heating profile was changed from shot to shot over a wide range from localized on-axis, with normalized minor radius half-width at half maximum σ1/2 ~ 0.1, up to a widely distributed heating power profile with σ1/2 ~ 0.4 and finally to a profile peaked far off-axis. The global confinement, MHD activity, density, temperature and electron pressure profile evolution were compared. In particular, the energy confinement properties of discharges with localized on-axis heating and distributed on-axis heating were very similar, with degradation close to that predicted by the ITER L-mode scaling; in the case of off-axis heating, on the other hand, the confinement degradation was even stronger.

  9. Streambed microstructure predicts evolution of development and life history mode in the plethodontid salamander Eurycea tynerensis

    PubMed Central

    Bonett, Ronald M; Chippindale, Paul T

    2006-01-01

    Background Habitat variation strongly influences the evolution of developmentally flexible traits, and may drive speciation and diversification. The plethodontid salamander Eurycea tynerensis is endemic to the geologically diverse Ozark Plateau of south-central North America, and comprises both strictly aquatic paedomorphic populations (achieving reproductive maturity while remaining in the larval form) and more terrestrial metamorphic populations. The switch between developmental modes has occurred many times, but populations typically exhibit a single life history mode. This unique system offers an opportunity to study the specific ecological circumstances under which alternate developmental and life history modes evolve. We use phylogenetic independent contrasts to test for relationships between a key microhabitat feature (streambed sediment) and this major life history polymorphism. Results We find streambed microstructure (sediment particle size, type and degree of sorting) to be highly correlated with life-history mode. Eurycea tynerensis is paedomorphic in streams containing large chert gravel, but metamorphoses in nearby streams containing poorly sorted, clastic material such as sandstone or siltstone. Conclusion Deposits of large chert gravel create loosely associated streambeds, which provide access to subsurface water during dry summer months. Conversely, streambeds composed of more densely packed sandstone and siltstone sediments leave no subterranean refuge when surface water dries, presumably necessitating metamorphosis and use of terrestrial habitats. This represents a clear example of the relationship between microhabitat structure and evolution of a major developmental and life history trait, and has broad implications for the role of localized ecological conditions on larger-scale evolutionary processes. PMID:16512919

  10. Zero-mode waveguides

    DOEpatents

    Levene, Michael J.; Korlach, Jonas; Turner, Stephen W.; Craighead, Harold G.; Webb, Watt W.

    2007-02-20

    The present invention is directed to a method and an apparatus for analysis of an analyte. The method involves providing a zero-mode waveguide which includes a cladding surrounding a core where the cladding is configured to preclude propagation of electromagnetic energy of a frequency less than a cutoff frequency longitudinally through the core of the zero-mode waveguide. The analyte is positioned in the core of the zero-mode waveguide and is then subjected, in the core of the zero-mode waveguide, to activating electromagnetic radiation of a frequency less than the cut-off frequency under conditions effective to permit analysis of the analyte in an effective observation volume which is more compact than if the analysis were carried out in the absence of the zero-mode waveguide.

  11. Retrieving atmospheric turbulence information from regular commercial aircraft using Mode-S and ADS-B

    NASA Astrophysics Data System (ADS)

    Kopeć, Jacek M.; Kwiatkowski, Kamil; de Haan, Siebren; Malinowski, Szymon P.

    2016-05-01

    Navigational information broadcast by commercial aircraft in the form of Mode-S EHS (Mode-S Enhanced Surveillance) and ADS-B (Automatic Dependent Surveillance-Broadcast) messages can be considered a new source of upper tropospheric and lower stratospheric turbulence estimates. A set of three processing methods is proposed and analysed using a quality record of turbulence encounters made by a research aircraft.The proposed methods are based on processing the vertical acceleration or the background wind into the eddy dissipation rate. Turbulence intensity can be estimated using the standard content of the Mode-S EHS/ADS-B.The results are based on a Mode-S EHS/ADS-B data set generated synthetically based on the transmissions from the research aircraft. This data set was validated using the overlapping record of the Mode-S EHS/ADS-B received from the same research aircraft. The turbulence intensity, meaning the eddy dissipation rate, obtained from the proposed methods based on the Mode-S EHS/ADS-B is compared with the value obtained using on-board accelerometer. The results of the comparison indicate the potential of the methods. The advantages and limitation of the presented approaches are discussed.

  12. Spatial Patterns of Sea Level Variability Associated with Natural Internal Climate Modes

    NASA Astrophysics Data System (ADS)

    Han, Weiqing; Meehl, Gerald A.; Stammer, Detlef; Hu, Aixue; Hamlington, Benjamin; Kenigson, Jessica; Palanisamy, Hindumathi; Thompson, Philip

    2017-01-01

    Sea level rise (SLR) can exert significant stress on highly populated coastal societies and low-lying island countries around the world. Because of this, there is huge societal demand for improved decadal predictions and future projections of SLR, particularly on a local scale along coastlines. Regionally, sea level variations can deviate considerably from the global mean due to various geophysical processes. These include changes of ocean circulations, which partially can be attributed to natural, internal modes of variability in the complex Earth's climate system. Anthropogenic influence may also contribute to regional sea level variations. Separating the effects of natural climate modes and anthropogenic forcing, however, remains a challenge and requires identification of the imprint of specific climate modes in observed sea level change patterns. In this paper, we review our current state of knowledge about spatial patterns of sea level variability associated with natural climate modes on interannual-to-multidecadal timescales, with particular focus on decadal-to-multidecadal variability. Relevant climate modes and our current state of understanding their associated sea level patterns and driving mechanisms are elaborated separately for the Pacific, the Indian, the Atlantic, and the Arctic and Southern Oceans. We also discuss the issues, challenges and future outlooks for understanding the regional sea level patterns associated with climate modes. Effects of these internal modes have to be taken into account in order to achieve more reliable near-term predictions and future projections of regional SLR.

  13. Self reported fear of childbirth and its association with women's birth experience and mode of delivery: a longitudinal population-based study.

    PubMed

    Nilsson, Christina; Lundgren, Ingela; Karlström, Annika; Hildingsson, Ingegerd

    2012-09-01

    To explore fear of childbirth (FOC) during pregnancy and one year after birth and its association to birth experience and mode of delivery. A longitudinal population-based study. Pregnant women who were listed for a routine ultrasound at three hospitals in the middle-north part of Sweden. Differences between women who reported FOC and who did not were calculated using risk ratios with a 95% confidence interval. In order to explain which factors were most strongly associated to suffer from FOC during pregnancy and one year after childbirth, multivariate logistic regression analyses were used. FOC during pregnancy in multiparous women was associated with a previous negative birth experience (RR 5.1, CI 2.5-10.4) and a previous emergency caesarean section (RR 2.5, CI 1.2-5.4). Associated factors for FOC one year after childbirth were: a negative birth experience (RR 10.3, CI 5.1-20.7), fear of childbirth during pregnancy (RR 7.1, CI 4.4-11.7), emergency caesarean section (RR 2.4, CI 1.2-4.5) and primiparity (RR 1.9, CI 1.2-3.1). FOC was associated with negative birth experiences. Women still perceived the birth experience as negative a year after the event. Women's perception of the overall birth experience as negative seems to be more important for explaining subsequent FOC than mode of delivery. Maternity care should focus on women's experiences of childbirth. Staff at antenatal clinics should ask multiparous women about their previous experience of childbirth. So that FOC is minimized, research on factors that create a positive birth experience for women is required. Copyright © 2011 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

  14. Multiphoton endoscopy based on a mode-filtered single-mode fiber

    NASA Astrophysics Data System (ADS)

    Moon, Sucbei; Liu, Gangjun; Chen, Zhongping

    2011-03-01

    We present a new low-nonlinearity fiber of mode-filtered large-core fiber for flexible beam delivery of intense pulsed light aiming at multi-photon endoscopy application. A multimode fiber of a large core diameter (20 μm) equips a mode filtering means in the middle of the fiber link to suppress the high-order modes selectively. A large effective core area of ~200 μm2 has been achieved at 0.8-μm and 1.0-μm bands. This is 8 times larger than the core area of a conventional SMF used for those spectral bands. Various advantages of our large-mode area fiber will be demonstrated and discussed in this report.

  15. Potential fitness benefits of the half-pounder life history in Klamath River steelhead

    USGS Publications Warehouse

    Hodge, Brian W.; Wilzbach, Peggy; Duffy, Walter G.

    2014-01-01

    Steelhead Oncorhynchus mykiss from several of the world's rivers display the half-pounder life history, a variant characterized by an amphidromous (and, less often, anadromous) return to freshwater in the year of initial ocean entry. We evaluated factors related to expression of the half-pounder life history in wild steelhead from the lower Klamath River basin, California. We also evaluated fitness consequences of the half-pounder phenotype using a simple life history model that was parameterized with our empirical data and outputs from a regional survival equation. The incidence of the half-pounder life history differed among subbasins of origin and smolt ages. Precocious maturation occurred in approximately 8% of half-pounders and was best predicted by individual length in freshwater preceding ocean entry. Adult steelhead of the half-pounder phenotype were smaller and less fecund at age than adult steelhead of the alternative (ocean contingent) phenotype. However, our data suggest that fish of the half-pounder phenotype are more likely to spawn repeatedly than are fish of the ocean contingent phenotype. Models predicted that if lifetime survivorship were equal between phenotypes, the fitness of the half-pounder phenotype would be 17–28% lower than that of the ocean contingent phenotype. To meet the condition of equal fitness between phenotypes would require that first-year ocean survival be 21–40% higher among half-pounders in freshwater than among their cohorts at sea. We concluded that continued expression of the half-pounder phenotype is favored by precocious maturation and increased survival relative to that of the ocean contingent phenotype.

  16. Tracking coherent population transfer and thermal population relaxation in condensed system by broad-band transient grating spectroscopy

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Liu, Xiaosong; Wu, Honglin; Song, Yunfei; Liu, Weilong; Yang, Yanqiang

    2018-04-01

    Broad-band transient grating (BB-TG) spectroscopy was proposed to track both coherent population transfer (CPT) and thermal population relaxation processes in a condensed system of solvated molecules in solution (Rhodamine101 in methanol). A broad band around 1500 cm‑1 and a relative narrow band near 2900 cm‑1 emerge in TG and transient absorption contour plots when pump and probe pulses overlap in the sample. The experimental results matched well with the vibrational modes of Rhodamine101 that were obtained by theoretical calculation. In addition, it was found that the population of CPT particles can be evaluated quantitatively through the intensity of the TG signal.

  17. Design of a high power TM01 mode launcher optimized for manufacturing by milling

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

    Dal Forno, Massimo

    2016-12-15

    Recent research on high-gradient rf acceleration found that hard metals, such as hard copper and hard copper-silver, have lower breakdown rate than soft metals. Traditional high-gradient accelerating structures are manufactured with parts joined by high-temperature brazing. The high temperature used in brazing makes the metal soft; therefore, this process cannot be used to manufacture structures out of hard metal alloys. In order to build the structure with hard metals, the components must be designed for joining without high-temperature brazing. One method is to build the accelerating structures out of two halves, and join them by using a low-temperature technique, atmore » the symmetry plane along the beam axis. The structure has input and output rf power couplers. We use a TM01 mode launcher as a rf power coupler, which was introduced during the Next Linear Collider (NLC) work. The part of the mode launcher will be built in each half of the structure. This paper presents a novel geometry of a mode launcher, optimized for manufacturing by milling. The coupler was designed for the CERN CLIC working frequency f = 11.9942 GHz; the same geometry can be scaled to any other frequency.« less

  18. The etiologic role of genetic and environmental factors in criminal behavior as determined from full- and half-sibling pairs: an evaluation of the validity of the twin method.

    PubMed

    Kendler, K S; Lönn, S L; Maes, H H; Sundquist, J; Sundquist, K

    2015-07-01

    Twin studies have shown that criminal behavior (CB) is influenced by both genetic and shared environmental factors. Could these results be replicated using full-siblings and half-siblings? In 911 009 full-siblings reared together (FSRT), 41 872 half-siblings reared together (HSRT) and 52 590 half-siblings reared apart (HSRA), CB was assessed from the Swedish Crime Register. Modeling, including testing for age differences and rearing status, was performed using the OpenMx package. Five sibling models were fitted examining FSRT and HSRT 0-2 years different in age, and both FSRT and HSRT, and FSRT, HSRT and HSRA 0-10 years different in age with and without a specified shared environment indexing age differences. Heritability estimates for CB ranged from 33 to 55% in females and 39 to 56% in males, similar to those found in our prior twin study on the same population. Estimates for the shared environment varied from 1 to 14% in females and 10 to 23% in males, lower than those estimated in the twin study. The specified shared environment indexed by sibling age differences was significant in all models tested. Heritability estimates for CB from full- and half-siblings closely approximated those found from twins in the same population, validating the twin method. Shared environmental estimates were lower, suggesting the presence of shared environmental factors for CB specific to twins. When rearing status can be assessed, full- and half-siblings offer an additional method for assessing the role of genetic and environmental factors in complex disorders. However, age differences in siblings may need to be included in the models.

  19. Multi-mode radio frequency device

    DOEpatents

    Gilbert, Ronald W [Morgan Hill, CA; Carrender, Curtis Lee [Morgan Hill, CA; Anderson, Gordon A [Benton City, WA; Steele, Kerry D [Kennewick, WA

    2007-02-13

    A transponder device having multiple modes of operation, such as an active mode and a passive mode, wherein the modes of operation are selected in response to the strength of a received radio frequency signal. A communication system is also provided having a transceiver configured to transmit a radio frequency signal and to receive a responsive signal, and a transponder configured to operate in a plurality of modes and to activate modes of operation in response to the radio frequency signal. Ideally, each mode of operation is activated and deactivated independent of the other modes, although two or more modes may be concurrently operational.

  20. All-fiber-based selective mode multiplexer and demultiplexer for weakly-coupled mode-division multiplexed systems

    NASA Astrophysics Data System (ADS)

    Igarashi, Koji; Park, Kyung Jun; Tsuritani, Takahiro; Morita, Itsuro; Kim, Byoung Yoon

    2018-02-01

    We show all-fiber-based selective mode multiplexers and demultiplexers for weakly-coupled mode-division multiplexed systems. We fabricate a set of six-mode multiplexer and demultiplexer based on fiber mode selective couplers, and experimentally evaluate the performance for the six-mode dual-polarization (DP) quadrature phase shift keying (QPSK) optical signals. In the mode multiplexer and demultiplexer, the mode couplings between the lower three modes and the higher three modes are suppressed to be less than -20 dB, which enables us to apply partial 6 ×6 MIMO equalizers even for the six-mode demultiplexing. For the six-mode DP-QPSK signals, the penalty of optical signal-to-noise ratio by replacing the full 12 ×12MIMO to the partial 6 ×6 MIMO is suppressed by less than 1 dB.

  1. Genetic association between the interleukin-2 receptor-alpha gene and mode of onset of type 1 diabetes in the Japanese population.

    PubMed

    Kawasaki, Eiji; Awata, Takuya; Ikegami, Hiroshi; Kobayashi, Tetsuro; Maruyama, Taro; Nakanishi, Koji; Shimada, Akira; Uga, Miho; Kurihara, Susumu; Kawabata, Yumiko; Tanaka, Shoichiro; Kanazawa, Yasuhiko; Eguchi, Katsumi

    2009-03-01

    The IL-2 receptor-alpha (IL2RA), also known as CD25, is expressed on the regulatory T cells, which play an important role in the control of immune responses and the maintenance of immune homeostasis. Our objective was to determine whether variants in the IL2RA gene are associated with type 1 diabetes in the Japanese population. We genotyped the four single-nucleotide polymorphisms (rs706778, rs3118470, ss52580101, and rs11594656) of the IL2RA in 885 patients with type 1 diabetes and 606 control subjects of Japanese origin. The allele and genotype frequencies were examined in the patient groups stratified by their mode of onset in a case-control study. We found evidence of association with acute-onset, but not slow-onset and fulminant, type 1 diabetes for two of the four single-nucleotide polymorphisms genotyped (rs706778 and rs3118470). The rs706778 A allele and the rs3118470 G allele were associated with an increased disease risk [odds ratio (OR) for rs706778 AA genotype 1.54, P = 4.2 x 10(-4) and OR for rs3118470 GG genotype 1.50, P = 0.0019, respectively]. Furthermore, the A-G haplotype was associated with increased type 1 diabetes risk in the acute-onset form (OR 1.30, P = 0.002). The present data confirm the type 1 diabetes association with IL2RA and provide evidence that the different contributions of the IL2RA in the susceptibility to acute-onset and other forms of type 1 diabetes in the Japanese population.

  2. Performance of a continuously rotating half-wave plate on the POLARBEAR telescope

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

    Takakura, Satoru; Aguilar, Mario; Akiba, Yoshiki

    A continuously rotating half-wave plate (CRHWP) is a promising tool to improve the sensitivity to large angular scales in cosmic microwave background (CMB) polarization measurements. With a CRHWP, single detectors can measure three of the Stokes parameters, I, Q and U, thereby avoiding the set of systematic errors that can be introduced by mismatches in the properties of orthogonal detector pairs. We focus on the implementation of CRHWPs in large aperture telescopes (i.e. the primary mirror is larger than the current maximum half-wave plate diameter of ~0.5 m), where the CRHWP can be placed between the primary mirror and focalmore » plane. In this configuration, one needs to address the intensity to polarization (I→P) leakage of the optics, which becomes a source of 1/f noise and also causes differential gain systematics that arise from CMB temperature fluctuations. In this paper, we present the performance of a CRHWP installed in the {\\scshape Polarbear} experiment, which employs a Gregorian telescope with a 2.5 m primary illumination pattern. The CRHWP is placed near the prime focus between the primary and secondary mirrors. We find that the I→P leakage is larger than the expectation from the physical properties of our primary mirror, resulting in a 1/f knee of 100 mHz. The excess leakage could be due to imperfections in the detector system, i.e. detector non-linearity in the responsivity and time-constant. We demonstrate, however, that by subtracting the leakage correlated with the intensity signal, the 1/f noise knee frequency is reduced to 32 mHz (ℓ ~ 39 for our scan strategy), which is very promising to probe the primordial B-mode signal. We also discuss methods for further noise subtraction in future projects where the precise temperature control of instrumental components and the leakage reduction will play a key role.« less

  3. Performance of a continuously rotating half-wave plate on the POLARBEAR telescope

    DOE PAGES

    Takakura, Satoru; Aguilar, Mario; Akiba, Yoshiki; ...

    2017-05-03

    A continuously rotating half-wave plate (CRHWP) is a promising tool to improve the sensitivity to large angular scales in cosmic microwave background (CMB) polarization measurements. With a CRHWP, single detectors can measure three of the Stokes parameters, I, Q and U, thereby avoiding the set of systematic errors that can be introduced by mismatches in the properties of orthogonal detector pairs. We focus on the implementation of CRHWPs in large aperture telescopes (i.e. the primary mirror is larger than the current maximum half-wave plate diameter of ~0.5 m), where the CRHWP can be placed between the primary mirror and focalmore » plane. In this configuration, one needs to address the intensity to polarization (I→P) leakage of the optics, which becomes a source of 1/f noise and also causes differential gain systematics that arise from CMB temperature fluctuations. In this paper, we present the performance of a CRHWP installed in the {\\scshape Polarbear} experiment, which employs a Gregorian telescope with a 2.5 m primary illumination pattern. The CRHWP is placed near the prime focus between the primary and secondary mirrors. We find that the I→P leakage is larger than the expectation from the physical properties of our primary mirror, resulting in a 1/f knee of 100 mHz. The excess leakage could be due to imperfections in the detector system, i.e. detector non-linearity in the responsivity and time-constant. We demonstrate, however, that by subtracting the leakage correlated with the intensity signal, the 1/f noise knee frequency is reduced to 32 mHz (ℓ ~ 39 for our scan strategy), which is very promising to probe the primordial B-mode signal. We also discuss methods for further noise subtraction in future projects where the precise temperature control of instrumental components and the leakage reduction will play a key role.« less

  4. Performance of a continuously rotating half-wave plate on the POLARBEAR telescope

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

    Takakura, Satoru; Aguilar, Mario; Akiba, Yoshiki

    A continuously rotating half-wave plate (CRHWP) is a promising tool to improve the sensitivity to large angular scales in cosmic microwave background (CMB) polarization measurements. With a CRHWP, single detectors can measure three of the Stokes parameters, I , Q and U , thereby avoiding the set of systematic errors that can be introduced by mismatches in the properties of orthogonal detector pairs. We focus on the implementation of CRHWPs in large aperture telescopes (i.e. the primary mirror is larger than the current maximum half-wave plate diameter of ∼0.5 m), where the CRHWP can be placed between the primary mirrormore » and focal plane. In this configuration, one needs to address the intensity to polarization ( I → P ) leakage of the optics, which becomes a source of 1/f noise and also causes differential gain systematics that arise from CMB temperature fluctuations. In this paper, we present the performance of a CRHWP installed in the (\\scshape Polarbear) experiment, which employs a Gregorian telescope with a 2.5 m primary illumination pattern. The CRHWP is placed near the prime focus between the primary and secondary mirrors. We find that the I → P leakage is larger than the expectation from the physical properties of our primary mirror, resulting in a 1/f knee of 100 mHz. The excess leakage could be due to imperfections in the detector system, i.e. detector non-linearity in the responsivity and time-constant. We demonstrate, however, that by subtracting the leakage correlated with the intensity signal, the 1/f noise knee frequency is reduced to 32 mHz (ℓ ∼ 39 for our scan strategy), which is very promising to probe the primordial B-mode signal. We also discuss methods for further noise subtraction in future projects where the precise temperature control of instrumental components and the leakage reduction will play a key role.« less

  5. Leadership in Higher Education and the Second Half of Life

    ERIC Educational Resources Information Center

    Mills, Roxanne

    2006-01-01

    Research indicates that little is understood about the impact of what has been called "the second half of life" on administrators in higher education, such as deans and department chairs. This study addresses this lack of knowledge by reviewing research on the second half of life phenomena, especially its possible impact on university/college…

  6. Recovery from forward masking in cochlear implant listeners depends on stimulation mode, level, and electrode location

    PubMed Central

    Chatterjee, Monita; Kulkarni, Aditya M.

    2017-01-01

    Psychophysical recovery from forward masking was measured in adult cochlear implant users of CochlearTM and Advanced BionicsTM devices, in monopolar and in focused (bipolar and tripolar) stimulation modes, at four electrode sites across the arrays, and at two levels (loudness balanced across modes and electrodes). Results indicated a steeper psychophysical recovery from forward masking in monopolar over bipolar and tripolar modes, modified by differential effects of electrode and level. The interactions between factors varied somewhat across devices. It is speculated that psychophysical recovery from forward masking may be driven by different populations of neurons in the different modes, with a broader stimulation pattern resulting in a greater likelihood of response by healthier and/or faster-recovering neurons within the stimulated population. If a more rapid recovery from prior stimulation reflects responses of neurons not necessarily close to the activating site, the spectral pattern of the incoming acoustic signal may be distorted. These results have implications for speech processor implementations using different degrees of focusing of the electric field. The primary differences in the shape of the recovery function were observed in the earlier portion (between 2 and 45 ms) of recovery, which is significant in terms of the speech envelope. PMID:28682084

  7. Burst-mode optical label processor with ultralow power consumption.

    PubMed

    Ibrahim, Salah; Nakahara, Tatsushi; Ishikawa, Hiroshi; Takahashi, Ryo

    2016-04-04

    A novel label processor subsystem for 100-Gbps (25-Gbps × 4λs) burst-mode optical packets is developed, in which a highly energy-efficient method is pursued for extracting and interfacing the ultrafast packet-label to a CMOS-based processor where label recognition takes place. The method involves performing serial-to-parallel conversion for the label bits on a bit-by-bit basis by using an optoelectronic converter that is operated with a set of optical triggers generated in a burst-mode manner upon packet arrival. Here we present three key achievements that enabled a significant reduction in the total power consumption and latency of the whole subsystem; 1) based on a novel operation mechanism for providing amplification with bit-level selectivity, an optical trigger pulse generator, that consumes power for a very short duration upon packet arrival, is proposed and experimentally demonstrated, 2) the energy of optical triggers needed by the optoelectronic serial-to-parallel converter is reduced by utilizing a negative-polarity signal while employing an enhanced conversion scheme entitled the discharge-or-hold scheme, 3) the necessary optical trigger energy is further cut down by half by coupling the triggers through the chip's backside, whereas a novel lens-free packaging method is developed to enable a low-cost alignment process that works with simple visual observation.

  8. List mode multichannel analyzer

    DOEpatents

    Archer, Daniel E [Livermore, CA; Luke, S John [Pleasanton, CA; Mauger, G Joseph [Livermore, CA; Riot, Vincent J [Berkeley, CA; Knapp, David A [Livermore, CA

    2007-08-07

    A digital list mode multichannel analyzer (MCA) built around a programmable FPGA device for onboard data analysis and on-the-fly modification of system detection/operating parameters, and capable of collecting and processing data in very small time bins (<1 millisecond) when used in histogramming mode, or in list mode as a list mode MCA.

  9. Image-driven Population Analysis through Mixture Modeling

    PubMed Central

    Sabuncu, Mert R.; Balci, Serdar K.; Shenton, Martha E.; Golland, Polina

    2009-01-01

    We present iCluster, a fast and efficient algorithm that clusters a set of images while co-registering them using a parameterized, nonlinear transformation model. The output of the algorithm is a small number of template images that represent different modes in a population. This is in contrast with traditional, hypothesis-driven computational anatomy approaches that assume a single template to construct an atlas. We derive the algorithm based on a generative model of an image population as a mixture of deformable template images. We validate and explore our method in four experiments. In the first experiment, we use synthetic data to explore the behavior of the algorithm and inform a design choice on parameter settings. In the second experiment, we demonstrate the utility of having multiple atlases for the application of localizing temporal lobe brain structures in a pool of subjects that contains healthy controls and schizophrenia patients. Next, we employ iCluster to partition a data set of 415 whole brain MR volumes of subjects aged 18 through 96 years into three anatomical subgroups. Our analysis suggests that these subgroups mainly correspond to age groups. The templates reveal significant structural differences across these age groups that confirm previous findings in aging research. In the final experiment, we run iCluster on a group of 15 patients with dementia and 15 age-matched healthy controls. The algorithm produces two modes, one of which contains dementia patients only. These results suggest that the algorithm can be used to discover sub-populations that correspond to interesting structural or functional “modes.” PMID:19336293

  10. Partially coherent surface plasmon modes

    NASA Astrophysics Data System (ADS)

    Niconoff, G. M.; Vara, P. M.; Munoz-Lopez, J.; Juárez-Morales, J. C.; Carbajal-Dominguez, A.

    2011-04-01

    Elementary long-range plasmon modes are described assuming an exponential dependence of the refractive index in the neighbourhood of the interface dielectric-metal thin film. The study is performed using coupling mode theory. The interference between two long-range plasmon modes generated that way allows the synthesis of surface sinusoidal plasmon modes, which can be considered as completely coherent generalized plasmon modes. These sinusoidal plasmon modes are used for the synthesis of new partially coherent surface plasmon modes, which are obtained by means of an incoherent superposition of sinusoidal plasmon modes where the period of each one is considered as a random variable. The kinds of surface modes generated have an easily tuneable profile controlled by means of the probability density function associated to the period. We show that partially coherent plasmon modes have the remarkable property to control the length of propagation which is a notable feature respect to the completely coherent surface plasmon mode. The numerical simulation for sinusoidal, Bessel, Gaussian and Dark Hollow plasmon modes are presented.

  11. Large area and deep sub-wavelength interference lithography employing odd surface plasmon modes.

    PubMed

    Liu, Liqin; Luo, Yunfei; Zhao, Zeyu; Zhang, Wei; Gao, Guohan; Zeng, Bo; Wang, Changtao; Luo, Xiangang

    2016-07-28

    In this paper, large area and deep sub-wavelength interference patterns are realized experimentally by using odd surface plasmon modes in the metal/insulator/metal structure. Theoretical investigation shows that the odd modes possesses much higher transversal wave vector and great inhibition of tangential electric field components, facilitating surface plasmon interference fringes with high resolution and contrast in the measure of electric field intensity. Interference resist patterns with 45 nm (∼λ/8) half-pitch, 50 nm depth, and area size up to 20 mm × 20 mm were obtained by using 20 nm Al/50 nm photo resist/50 nm Al films with greatly reduced surface roughness and 180 nm pitch exciting grating fabricated with conventional laser interference lithography. Much deeper resolution down to 19.5 nm is also feasible by decreasing the thickness of PR. Considering that no requirement of expensive EBL or FIB tools are employed, it provides a cost-effective way for large area and nano-scale fabrication.

  12. A general solution strategy of modified power method for higher mode solutions

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

    Zhang, Peng; Lee, Hyunsuk; Lee, Deokjung, E-mail: deokjung@unist.ac.kr

    2016-01-15

    A general solution strategy of the modified power iteration method for calculating higher eigenmodes has been developed and applied in continuous energy Monte Carlo simulation. The new approach adopts four features: 1) the eigen decomposition of transfer matrix, 2) weight cancellation for higher modes, 3) population control with higher mode weights, and 4) stabilization technique of statistical fluctuations using multi-cycle accumulations. The numerical tests of neutron transport eigenvalue problems successfully demonstrate that the new strategy can significantly accelerate the fission source convergence with stable convergence behavior while obtaining multiple higher eigenmodes at the same time. The advantages of the newmore » strategy can be summarized as 1) the replacement of the cumbersome solution step of high order polynomial equations required by Booth's original method with the simple matrix eigen decomposition, 2) faster fission source convergence in inactive cycles, 3) more stable behaviors in both inactive and active cycles, and 4) smaller variances in active cycles. Advantages 3 and 4 can be attributed to the lower sensitivity of the new strategy to statistical fluctuations due to the multi-cycle accumulations. The application of the modified power method to continuous energy Monte Carlo simulation and the higher eigenmodes up to 4th order are reported for the first time in this paper. -- Graphical abstract: -- Highlights: •Modified power method is applied to continuous energy Monte Carlo simulation. •Transfer matrix is introduced to generalize the modified power method. •All mode based population control is applied to get the higher eigenmodes. •Statistic fluctuation can be greatly reduced using accumulated tally results. •Fission source convergence is accelerated with higher mode solutions.« less

  13. Mode coupling in vortex beams

    NASA Astrophysics Data System (ADS)

    Eyyuboğlu, Halil T.

    2018-05-01

    We examine the mode coupling in vortex beams. Mode coupling also known as the crosstalk takes place due to turbulent characteristics of the atmospheric communication medium. This way, the transmitted intrinsic mode of the vortex beam leaks power to other extrinsic modes, thus preventing the correct detection of the transmitted symbol which is usually encoded into the mode index or the orbital angular momentum state of the vortex beam. Here we investigate the normalized power mode coupling ratios of several types of vortex beams, namely, Gaussian vortex beam, Bessel Gaussian beam, hypergeometric Gaussian beam and Laguerre Gaussian beam. It is found that smaller mode numbers lead to less mode coupling. The same is partially observed for increasing source sizes. Comparing the vortex beams amongst themselves, it is seen that hypergeometric Gaussian beam is the one retaining the most power in intrinsic mode during propagation, but only at lowest mode index of unity. At higher mode indices this advantage passes over to the Gaussian vortex beam.

  14. Improved measurement of the half-life of the J π = 8 - nuclear isomer 152m2 Eu

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

    Humby, Peter; Simon, Anna; Beausang, C. W.

    2015-02-23

    The standard γ-ray energy calibration source 152Eu is well known based on the 13.5 y decay of its ground state. Nevertheless, in addition to this decay 152Eu also has two relatively long-lived isomeric states: a 9 h J π=0 - state at E *=46 keV and a 96 min J π=8 - state at E *=148 keV. Here we report a new measurement of the half-lives of both of these isomeric states. Excited states in 152Eu were populated following the 154Sm (p,3n) reaction using a 25 MeV proton beam from the K-150 cyclotron at the Cyclotron Institute of Texas A&Mmore » University. Post irradiation, γ rays from the de-excitation of the long lived isomeric states were measured using the six BGO shielded high-purity germanium (HPGe) clover detectors that are part of the STARLiTeR array. The half-life of the J π=8 - isomer 152m2Eu was obtained by measuring the decrease in intensity of the 90 keV γ ray from the cascade to the ground state. The half-life of this state was measured to be 95.8(4) min which is in agreement with and significantly more precise than the previously measured value of 96(1) min. In a manner similar to the ground state the second long-lived isomer 151m1Eu, the J π=0 - state at 46 keV, β decays to excited states in 152Gd and 152Sm. Also, the half-life of this state was measured to be 9.39(7) h using five γ-ray transitions.« less

  15. Propagating annular modes

    NASA Astrophysics Data System (ADS)

    Sheshadri, A.; Plumb, R. A.

    2017-12-01

    The leading "annular mode", defined as the dominant EOF of surface pressure or of zonal mean zonal wind variability, appears as a dipolar structure straddling the mean midlatitude jet and thus seems to describe north-south wobbling of the jet latitude. However, extratropical zonal wind anomalies frequently tend to migrate poleward. This behavior can be described by the first two EOFs, the first (AM1) being the dipolar structure, and the second (AM2) having a tripolar structure centered on the mean jet. Taken in isolation, AM1 thus describes a north-south wobbling of the jet position, while AM2 describes a strengthening and narrowing of the jet. However, despite the fact that they are spatially orthogonal, and their corresponding time series temporally orthogonal, AM1 and AM2 are not independent, but show significant lag-correlations which reveal the propagation. The EOFs are not modes of the underlying dynamical system governing the zonal flow evolution. The true modes can be estimated using principal oscillation pattern (POP) analysis. In the troposphere, the leading POPs manifest themselves as a pair of complex conjugate structures with conjugate eigenvalues thus, in reality, constituting a single, complex, mode that describes propagating anomalies. Even though the principal components associated with the two leading EOFs decay at different rates, each decays faster than the true mode. These facts have implications for eddy feedback and the susceptibility of the mode to external perturbations. If one interprets the annular modes as the modes of the system, then simple theory predicts that the response to steady forcing will usually be dominated by AM1 (with the longest time scale). However, such arguments should really be applied to the true modes. Experiments with a simplified GCM show that climate response to perturbations do not necessarily have AM1 structures. Implications of these results for stratosphere-troposphere interactions are explored. The POP

  16. The phase-space dependence of fast-ion interaction with tearing modes

    DOE PAGES

    Heidbrink, William W.; Bardoczi, Laszlo; Collins, Cami S.; ...

    2018-03-19

    Modulation of various neutral beam sources probes the interaction of fast ions with tearing modes (TM) in the DIII-D tokamak. As measured by electron cyclotron emission, the (m,n) = (2,1) tearing modes have an island width of ~8 cm and change phase 180 at the q = 2 surface. (Here, m is the poloidal mode number and n is the toroidal mode number.) Deuterium neutral beam injection by six sources with differing injection geometries produces the fast ions. To study the interaction in different parts of phase space, on successive discharges, one of the six sources is modulated at 20more » Hz to populate different fast-ion orbits. The modulation only changes the island width by a few millimeters, implying that any fast-ion effect on mode stability is below detection limits. When compared to the expected signals in the absence of TM-induced transport, both the average and modulated neutron signals deviate, implying that fast-ion transport occurs in much of phase space. Fast-ion D-α (FIDA) measurements detect reductions in signal at wavelengths that are sensitive to counter-passing ions. Neutral particle analyzer data imply poor confinement of trapped fast ions. Lastly, calculations of the expected fast-ion transport that use measured TM properties successfully reproduce the data.« less

  17. The phase-space dependence of fast-ion interaction with tearing modes

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

    Heidbrink, William W.; Bardoczi, Laszlo; Collins, Cami S.

    Modulation of various neutral beam sources probes the interaction of fast ions with tearing modes (TM) in the DIII-D tokamak. As measured by electron cyclotron emission, the (m,n) = (2,1) tearing modes have an island width of ~8 cm and change phase 180 at the q = 2 surface. (Here, m is the poloidal mode number and n is the toroidal mode number.) Deuterium neutral beam injection by six sources with differing injection geometries produces the fast ions. To study the interaction in different parts of phase space, on successive discharges, one of the six sources is modulated at 20more » Hz to populate different fast-ion orbits. The modulation only changes the island width by a few millimeters, implying that any fast-ion effect on mode stability is below detection limits. When compared to the expected signals in the absence of TM-induced transport, both the average and modulated neutron signals deviate, implying that fast-ion transport occurs in much of phase space. Fast-ion D-α (FIDA) measurements detect reductions in signal at wavelengths that are sensitive to counter-passing ions. Neutral particle analyzer data imply poor confinement of trapped fast ions. Lastly, calculations of the expected fast-ion transport that use measured TM properties successfully reproduce the data.« less

  18. Personal birth preferences and actual mode of delivery outcomes of obstetricians and gynaecologists in South West England; with comparison to regional and national birth statistics.

    PubMed

    Lightly, Katie; Shaw, Elisabeth; Dailami, Narges; Bisson, Dina

    2014-10-01

    To determine personal birth preferences of obstetricians in various clinical scenarios, in particular elective caesarean section for maternal request. To determine actual rates of modes of deliveries amongst the same group. To compare the obstetrician's mode of delivery rates, to the general population. Following ethical approval, a piloted online survey link was sent via email to 242 current obstetricians and gynaecologists, (consultants and trainees) in South West England. Mode of delivery results were compared to regional and national population data, using Hospital Episode Statistics and subjected to statistical analysis. The response rate was 68%. 90% would hypothetically plan a vaginal delivery, 10% would consider a caesarean section in an otherwise uncomplicated primiparous pregnancy. Of the 94/165 (60%) respondents with children (201 children), mode of delivery for the first born child; normal vaginal delivery 48%, caesarean section 26.5% (elective 8.5%, emergency 18%), instrumental 24.5% and vaginal breech 1%. Only one chose an elective caesarean for maternal request. During 2006-2011 obstetricians have the same overall actual modes of birth as the population (p=0.9). Ten percent of obstetricians report they would consider requesting caesarean section for themselves/their partner, which is the lowest rate reported within UK studies. However only 1% actually had a caesarean solely for maternal choice. When compared to regional/national statistics obstetricians currently have modes of delivery that are not significantly different than the population and suggests that they choose non interventional delivery if possible. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  19. Subcritical crack growth in soda-lime glass in combined mode I and mode II loading

    NASA Technical Reports Server (NTRS)

    Singh, Dileep; Shetty, Dinesh K.

    1990-01-01

    Subcritical crack growth under mixed-mode loading was studied in soda-lime glass. Pure mode I, combined mode I and mode II, and pure mode II loadings were achieved in precracked disk specimens by loading in diametral compression at selected angles with respect to the symmetric radial crack. Crack growth was monitored by measuring the resistance changes in a microcircuit grid consisting of parallel, electrically conducting grid lines deposited on the surface of the disk specimens by photolithography. Subcritical crack growth rates in pure mode I, pure mode II, and combined mode I and mode II loading could be described by an exponential relationship between crack growth rate and an effective crack driving force derived from a mode I-mode II fracture toughness envelope. The effective crack driving force was based on an empirical representation of the noncoplanar strain energy release rate. Stress intensities for kinked cracks were assessed using the method of caustics and an initial decrease and a subsequent increase in the subcritical crack growth rates of kinked cracks were shown to correlate with the variations of the mode I and the mode II stress intensities.

  20. Half-metallic ferromagnetism in substitutionally doped boronitrene

    NASA Astrophysics Data System (ADS)

    Ukpong, A. M.; Chetty, N.

    2012-11-01

    We perform first-principles molecular dynamics simulations to investigate the magnetoelectronic response of substitutionally doped boronitrene to thermal excitation. We show that the local geometry, size, and edge termination of the substitutional complexes of boron, carbon, or nitrogen determine the thermodynamic stability of the monolayer. We find that hexagonal boron or triangular carbon clusters induce finite magnetic moments with 100% spin-polarized Fermi-level electrons in boronitrene. In such carbon substitutions, the spontaneous magnetic moment increases with the size of the embedded carbon cluster, and results in half-metallic ferrimagnetism above 750 K with a corresponding Curie point of 1250 K, above which the magnetization density vanishes. We predict an ultrahigh temperature half-metallic ferromagnetic phase in impurity-free boronitrene, when any three nearest-neighbor nitrogen atoms are substituted with boron, with unquenched magnetic moment up to its melting point.

  1. A high repetition rate passively Q-switched microchip laser for controllable transverse laser modes

    NASA Astrophysics Data System (ADS)

    Dong, Jun; Bai, Sheng-Chuang; Liu, Sheng-Hui; Ueda, Ken-Ichi; Kaminskii, Alexander A.

    2016-05-01

    A Cr4+:YAG passively Q-switched Nd:YVO4 microchip laser for versatile controllable transverse laser modes has been demonstrated by adjusting the position of the Nd:YVO4 crystal along the tilted pump beam direction. The pump beam diameter-dependent asymmetric saturated inversion population inside the Nd:YVO4 crystal governs the oscillation of various Laguerre-Gaussian, Ince-Gaussian and Hermite-Gaussian modes. Controllable transverse laser modes with repetition rates over 25 kHz and up to 183 kHz, depending on the position of the Nd:YVO4 crystal, have been achieved. The controllable transverse laser beams with a nanosecond pulse width and peak power over hundreds of watts have been obtained for potential applications in optical trapping and quantum computation.

  2. Mutiple Stellar Populations in Blanco DECam Bulge Survey Globular Clusters

    NASA Astrophysics Data System (ADS)

    Miller, Doryan; Pilachowski, C. A.; Johnson, C. I.; Rich, R. Michael; Clarkson, William I.; Young, M.; Michael, S.

    2018-01-01

    Preliminary SDSS ugrizY photometric observations of globular cluster stars included in the Blanco DECam Bulge Survey (BDBS) were examined to determine the suitability of these data to characterize stellar populations within clusters. The BDBS fields include around two dozen globular clusters, including the iron-complex cluster M22 and the pulsar-rich cluster Terzan 5. Many globular clusters show evidence for multiple stellar populations as a spread in the u-g color of stars in a given phase of stellar evolution, and in some clusters, the populations have different radial distributions. BDBS clusters with low and/or non-variable reddening and long dynamical mixing time scales were selected for study, and photometry for RGB and main sequence stars within two half-light radii from the center of each cluster was extracted from the BDBS preliminary catalog. Field contamination was reduced in each candidate cluster by removing all stars more than a tenth of a magnitude from the best-fit fiducial curves following the g-r vs r color-magnitude diagram. The remaining stars were split into separate populations based on u-g color, and effective cumulative distribution functions vs. half-light radius were compared to identify differences in the populations’ radial distributions.

  3. Mode of delivery is not associated with celiac disease.

    PubMed

    Dydensborg Sander, Stine; Hansen, Anne Vinkel; Størdal, Ketil; Andersen, Anne-Marie Nybo; Murray, Joseph A; Husby, Steffen

    2018-01-01

    The purpose of this study was to investigate the association between mode of delivery and the risk of celiac disease in two large population-based birth cohorts with different prevalence of diagnosed celiac disease. This is an observational register-based cohort study using two independent population cohorts. We used data from administrative registers and health administrative registers from Denmark and Norway and linked the data at the individual level. We included all children who were born in Denmark from January 1, 1995 to December 31, 2010 and all children who were born in Norway from January 1, 2004 to December 31, 2012. We included 1,051,028 children from Denmark. Cesarean sections were registered for 196,512 children (18.9%). Diagnosed celiac disease was registered for 1,395 children (0.13%). We included 537,457 children from Norway. Cesarean sections were registered for 90,128 children (16.8%). Diagnosed celiac disease was registered for 1,919 children (0.35%). We found no association between the mode of delivery and the risk of diagnosed celiac disease. The adjusted odds ratio for celiac disease for children delivered by any type of cesarean section compared to vaginal delivery was 1.11 (95% CI: 0.96-1.29) in the Danish cohort and 0.96 (95% CI: 0.84-1.09) in the Norwegian cohort. The adjusted odds ratio for celiac disease for children delivered by elective cesarean section compared to vaginal delivery was 1.20 (95% CI: 1.00-1.43) in the Danish cohort and 0.96 (95% CI: 0.79-1.17) in the Norwegian cohort. In this large registry-based study, mode of delivery was not associated with an increased risk of diagnosed celiac disease.

  4. Chromosomal changes during experimental evolution in laboratory populations of Escherichia coli.

    PubMed

    Bergthorsson, U; Ochman, H

    1999-02-01

    Short-term rates of chromosome evolution were analyzed in experimental populations of Escherichia coli B that had been propagated for 2,000 generations under four thermal regimens. Chromosome alterations were monitored in 24 independent populations by pulsed-field gel electrophoresis of DNA treated with five rare-cutting restriction enzymes. A total of 11 changes, 8 affecting chromosome size and 3 altering restriction sites, were observed in these populations, with none occurring in strains cultured at 37 degreesC. Considering the changes detected in these experimental populations, the rate of chromosome alteration of E. coli is estimated to be half of that observed in experimental populations of yeast.

  5. Broken symmetries, zero-energy modes, and quantum transport in disordered graphene: from supermetallic to insulating regimes.

    PubMed

    Cresti, Alessandro; Ortmann, Frank; Louvet, Thibaud; Van Tuan, Dinh; Roche, Stephan

    2013-05-10

    The role of defect-induced zero-energy modes on charge transport in graphene is investigated using Kubo and Landauer transport calculations. By tuning the density of random distributions of monovacancies either equally populating the two sublattices or exclusively located on a single sublattice, all conduction regimes are covered from direct tunneling through evanescent modes to mesoscopic transport in bulk disordered graphene. Depending on the transport measurement geometry, defect density, and broken sublattice symmetry, the Dirac-point conductivity is either exceptionally robust against disorder (supermetallic state) or suppressed through a gap opening or by algebraic localization of zero-energy modes, whereas weak localization and the Anderson insulating regime are obtained for higher energies. These findings clarify the contribution of zero-energy modes to transport at the Dirac point, hitherto controversial.

  6. ToF-SIMS Depth Profiling Of Insulating Samples, Interlaced Mode Or Non-interlaced Mode?

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

    Wang, Zhaoying; Jin, Ke; Zhang, Yanwen

    2014-11-01

    Dual beam depth profiling strategy has been widely adopted in ToF-SIMS depth profiling, in which two basic operation modes, interlaced mode and non-interlaced mode, are commonly used. Generally, interlaced mode is recommended for conductive or semi-conductive samples, whereas non-interlaced mode is recommended for insulating samples, where charge compensation can be an issue. Recent publications, however, show that the interlaced mode can be used effectively for glass depth profiling, despite the fact that glass is an insulator. In this study, we provide a simple guide for choosing between interlaced mode and non-interlaced mode for insulator depth profiling. Two representative cases aremore » presented: (1) depth profiling of a leached glass sample, and (2) depth profiling of a single crystal MgO sample. In brief, the interlaced mode should be attempted first, because (1) it may provide reasonable-quality data, and (2) it is time-saving for most cases, and (3) it introduces low H/C/O background. If data quality is the top priority and measurement time is flexible, non-interlaced mode is recommended because interlaced mode may suffer from low signal intensity and poor mass resolution. A big challenge is tracking trace H/C/O in a highly insulating sample (e.g., MgO), because non-interlaced mode may introduce strong H/C/O background but interlaced mode may suffer from low signal intensity. Meanwhile, a C or Au coating is found to be very effective to improve the signal intensity. Surprisingly, the best analyzing location is not on the C or Au coating, but at the edge (outside) of the coating.« less

  7. High-precision half-life determination for the superallowed β+ emitter Ga62

    NASA Astrophysics Data System (ADS)

    Grinyer, G. F.; Finlay, P.; Svensson, C. E.; Ball, G. C.; Leslie, J. R.; Austin, R. A. E.; Bandyopadhyay, D.; Chaffey, A.; Chakrawarthy, R. S.; Garrett, P. E.; Hackman, G.; Hyland, B.; Kanungo, R.; Leach, K. G.; Mattoon, C. M.; Morton, A. C.; Pearson, C. J.; Phillips, A. A.; Ressler, J. J.; Sarazin, F.; Savajols, H.; Schumaker, M. A.; Wong, J.

    2008-01-01

    The half-life of the superallowed β+ emitter Ga62 has been measured at TRIUMF's Isotope Separator and Accelerator facility using a fast-tape-transport system and 4π continuous-flow gas proportional counter to detect the positrons from the decay of Ga62 to the daughter Zn62. The result, T1/2=116.100±0.025 ms, represents the most precise measurement to date (0.022%) for any superallowed β-decay half-life. When combined with six previous measurements of the Ga62 half-life, a new world average of T1/2=116.121±0.021 ms is obtained. This new half-life measurement results in a 20% improvement in the precision of the Ga62 superallowed ft value while reducing its mean by 0.9σ to ft=3074.3(12) s. The impact of this half-life measurement on precision tests of the CVC hypothesis and isospin symmetry breaking corrections for A⩾62 superallowed decays is discussed.

  8. Half-metallicity and tetragonal distortion in semi-Heusler alloy FeCrSe

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

    Huang, H. M., E-mail: smilehhm@163.com; Luo, S. J.; Yao, K. L.

    2014-01-28

    Full-potential linearized augmented plane wave methods are carried out to investigate the electronic structures and magnetic properties in semi-Heusler alloy FeCrSe. Results show that FeCrSe is half-metallic ferromagnet with the half-metallic gap 0.31 eV at equilibrium lattice constant. Calculated total magnetic moment of 2.00μ{sub B} per formula unit follows the Slater-Pauling rule quite well. Two kinds of structural changes are used to investigate the sensitivity of half-metallicity. It is found that the half-metallicity can be retained when lattice constant is changed by −4.56% to 3.52%, and the results of tetragonal distortion indicate the half-metallicity can be kept at the range ofmore » c/a ratio from 0.85 to 1.20. The Curie temperature, cohesive energy, and heat of formations of FeCrSe are also discussed.« less

  9. A biomimetic approach for enhancing the in vivo half-life of peptides

    PubMed Central

    Penchala, Sravan C; Miller, Mark R; Pal, Arindom; Dong, Jin; Madadi, Nikhil R.; Xie, Jinghang; Joo, Hyun; Tsai, Jerry; Batoon, Patrick; Samoshin, Vyacheslav; Franz, Andreas; Cox, Trever; Miles, Jesse; Chan, William K; Park, Miki S; Alhamadsheh, Mamoun M

    2015-01-01

    The tremendous therapeutic potential of peptides has not yet been realized, mainly due to their short in vivo half-life. While conjugation to macromolecules has been a mainstay approach for enhancing the half-life of proteins, the steric hindrance of macromolecules often harms the binding of peptides to target receptors, compromising the in vivo efficacy. Here we report a new strategy for enhancing the in vivo half-life of peptides without compromising their potency. Our approach involves endowing peptides with a small-molecule that binds reversibly to the serum protein, transthyretin. Although there are few reversible albumin-binding molecules, we are unaware of designed small molecules that bind reversibly to other serum proteins and are used for half-life extension in vivo. We show here that our strategy was indeed effective in enhancing the half-life of an agonist for GnRH receptor while maintaining its binding affinity, which was translated into superior in vivo efficacy. PMID:26344696

  10. Relationship Between Locked Modes and Disruptions in the DIII-D Tokamak

    NASA Astrophysics Data System (ADS)

    Sweeney, Ryan

    cause a disruption or not, and does so up to hundreds of milliseconds before the disruption. Within 20 ms of the disruption, the shortest distance between the island separatrix and the unperturbed last closed flux surface, referred to as dedge, performs comparably to l i/q95 in its ability to discriminate disruptive locked modes, and it also correlates well with the duration of the locked mode. On average, and within errors, the n=1 perturbed field grows exponentially in the final 50 ms before a disruption, however, the island width cannot discern whether a LM will disrupt or not up to 20 ms before the disruption. A few discharges are selected to analyze the evolution of the electron temperature profile in the presence of multiple coexisting locked modes during partial and full thermal quenches. Partial thermal quenches are often an initial, distinct stage in the full thermal quench caused by radiation, conduction, or convection losses. Here we explore the fundamental mechanism that causes the partial quench. Near the onset of partial thermal quenches, locked islands are observed to align in a unique way, or island widths are observed to grow above a threshold. Energy analysis on one discharge suggests that about half of the energy is lost in the divertor region. In discharges with minimum values of the safety factor above ˜1.2, and with current profiles expected to be classically stable, locked modes are observed to self-stabilize by inducing a full thermal quench, possibly by double tearing modes that remove the pressure gradient across the island, thus removing the neoclassical drive.

  11. Assessment of Population and Microenvironmental Exposure to Fine Particulate Matter (PM2.5)

    NASA Astrophysics Data System (ADS)

    Jiao, Wan

    in exposure concentration, including ventilation air source, window status, fan setting, AC utilization, vehicle speed, road type, travel direction, and time of day. Another field data collection measured PM2.5 exposure concentrations on pre-selected routes across transportation modes of pedestrian, bus, and car to quantify the variability in the transportation mode concentration ratios, and identify factors affecting variability in traffic-related concentrations. In general, population daily average exposure to ambient PM2.5 is less than the ambient concentration by approximately half. The ratio of PM2.5 ambient exposure to ambient concentration (Ea/C) varies by individual, geographic area and season, as a result of regional differences in housing stock and seasonal differences in air exchange rates (ACH). For the indoor residence, the single-zone assumption is biased when any non-ambient source is presented. Bias correction factors are developed for cooking and smoking scenarios, separately, to improve the concentration estimates. Correction factors are most sensitive to changes in ACH but relatively insensitive to variations in source emission rate and duration. In a SHEDS-PM case study, the population daily average total exposure increased by 17% after applying correction factors. Transportation mode exposure concentrations are sensitive to mode, and are affected by factors such as vehicle ventilation and proximity to on-road emission sources. The in-vehicle to outside vehicle concentration (I/O) ratio is highly sensitive to whether windows are open or, for closed windows, to whether fresh air or recirculating air is used. Both model simulations and field studies are needed to inform better understanding of human exposure. Exposure, and not just concentration, should be considered in developing risk management strategies to reduce uncertainty in health effect estimates, and to identify highly exposed groups and possible exposure reduction strategies.

  12. Current steering with partial tripolar stimulation mode in cochlear implants.

    PubMed

    Wu, Ching-Chih; Luo, Xin

    2013-04-01

    The large spread of excitation is a major cause of poor spectral resolution for cochlear implant (CI) users. Partial tripolar (pTP) mode has been proposed to reduce current spread by returning an equally distributed fraction (0.5 × σ) of current to two flanking electrodes and the rest to an extra-cochlear ground. This study tested the efficacy of incorporating current steering into pTP mode to add spectral channels. Different proportions of current [α × σ and (1 - α) × σ] were returned to the basal and apical flanking electrodes respectively to shape the electric field. Loudness and pitch perception with α from 0 to 1 in steps of 0.1 was simulated with a computational model of CI stimulation and tested on the apical, middle, and basal electrodes of six CI subjects. The highest σ allowing for full loudness growth within the implant compliance limit was chosen for each main electrode. Pitch ranking was measured between pairs of loudness-balanced steered pTP stimuli with an α interval of 0.1 at the most comfortable level. Results demonstrated that steered pTP stimuli with α around 0.5 required more current to achieve equal loudness than those with α around 0 or 1, maybe due to more focused excitation patterns. Subjects usually perceived decreasing pitches as α increased from 0 to 1, somewhat consistent with the apical shift of the center of gravity of excitation pattern in the model. Pitch discrimination was not better with α around 0.5 than with α around 0 or 1, except for some subjects and electrodes. For three subjects with better pitch discrimination, about half of the pitch ranges of two adjacent main electrodes overlapped with each other in steered pTP mode. These results suggest that current steering with focused pTP mode may improve spectral resolution and pitch perception with CIs.

  13. Mode conversion efficiency to Laguerre-Gaussian OAM modes using spiral phase optics.

    PubMed

    Longman, Andrew; Fedosejevs, Robert

    2017-07-24

    An analytical model for the conversion efficiency from a TEM 00 mode to an arbitrary Laguerre-Gaussian (LG) mode with null radial index spiral phase optics is presented. We extend this model to include the effects of stepped spiral phase optics, spiral phase optics of non-integer topological charge, and the reduction in conversion efficiency due to broad laser bandwidth. We find that through optimization, an optimal beam waist ratio of the input and output modes exists and is dependent upon the output azimuthal mode number.

  14. New Measurement of the 60Fe Half-Life.

    PubMed

    Rugel, G; Faestermann, T; Knie, K; Korschinek, G; Poutivtsev, M; Schumann, D; Kivel, N; Günther-Leopold, I; Weinreich, R; Wohlmuther, M

    2009-08-14

    We have made a new determination of the half-life of the radioactive isotope 60Fe using high precision measurements of the number of 60Fe atoms and their activity in a sample containing over 10(15) 60Fe atoms. Our new value for the half-life of 60Fe is (2.62+/-0.04) x 10(6) yr, significantly above the previously reported value of (1.49+/-0.27) x 10(6) yr. Our new measurement for the lifetime of 60Fe has significant implications for interpretations of galactic nucleosynthesis, for determinations of formation time scales of solids in the early Solar System, and for the interpretation of live 60Fe measurements from supernova-ejecta deposits on Earth.

  15. Population catastrophe.

    PubMed

    Ankomah, B

    1990-07-01

    UNFPA estimates predict that Africa's population will be 1.5 billion by 2025. In the next 10 years the growth rate will be 3%, the highest for any region in human history. Nigeria is expected to have 301 million people in 35 years, making it the 3rd largest country behind India and China. Currently the economies of African countries can not provide enough jobs or food for the current population. What is going to happen in 35 years when the population will almost double? In 1950 Africa only made up 9% of the world population, but by 2025 it will be 18.4% of a global population of 8.4 billion. Currently half of Africa's population is under 15. This means that there is still time to affect change. There is time to convince this generation not to behave like their parents. A 2 child limit per family is an absolute limit if any progress is to be made that will actually have an effect. Many have suggested that the young people should go back to the land instead of living in poverty in the city. However, currently the land distribution is 0.4 hectares/rural person. This figure is going to drop to 0.29/rural person. Migration is simply not the solution. Many rural farmers want to have enough children to ensure that their land is inherited and stays in the family. The same goal can be achieved, with less children. According to the UNFPA 77% of married women who do not want to have more children do not use contraceptives. Only 14% of African women use contraceptives, so that by age 20 50% of African women have had 1 birth. The only way to seriously cut down the birth rate is to get the men of Africa involved in contraceptive use.

  16. The other half of the embodied mind.

    PubMed

    Parisi, Domenico

    2011-01-01

    Embodied theories of mind tend to be theories of the cognitive half of the mind and to ignore its emotional half while a complete theory of the mind should account for both halves. Robots are a new way of expressing theories of the mind which are less ambiguous and more capable to generate specific and non-controversial predictions than verbally expressed theories. We outline a simple robotic model of emotional states as states of a sub-part of the neural network controlling the robot's behavior which has specific properties and which allows the robot to make faster and more correct motivational decisions, and we describe possible extensions of the model to account for social emotional states and for the expression of emotions that, unlike those of current "emotional" robots, are really "felt" by the robot in that they play a well-identified functional role in the robot's behavior.

  17. Strategies to improve plasma half life time of peptide and protein drugs.

    PubMed

    Werle, M; Bernkop-Schnürch, A

    2006-06-01

    Due to the obvious advantages of long-acting peptide and protein drugs, strategies to prolong plasma half life time of such compounds are highly on demand. Short plasma half life times are commonly due to fast renal clearance as well as to enzymatic degradation occurring during systemic circulation. Modifications of the peptide/protein can lead to prolonged plasma half life times. By shortening the overall amino acid amount of somatostatin and replacing L: -analogue amino acids with D: -amino acids, plasma half life time of the derivate octreotide was 1.5 hours in comparison to only few minutes of somatostatin. A PEG(2,40 K) conjugate of INF-alpha-2b exhibited a 330-fold prolonged plasma half life time compared to the native protein. It was the aim of this review to provide an overview of possible strategies to prolong plasma half life time such as modification of N- and C-terminus or PEGylation as well as methods to evaluate the effectiveness of drug modifications. Furthermore, fundamental data about most important proteolytic enzymes of human blood, liver and kidney as well as their cleavage specificity and inhibitors for them are provided in order to predict enzymatic cleavage of peptide and protein drugs during systemic circulation.

  18. A Study of the Unstable Modes in High Mach Number Gaseous Jets and Shear Layers

    NASA Astrophysics Data System (ADS)

    Bassett, Gene Marcel

    1993-01-01

    Instabilities affecting the propagation of supersonic gaseous jets have been studied using high resolution computer simulations with the Piecewise-Parabolic-Method (PPM). These results are discussed in relation to jets from galactic nuclei. These studies involve a detailed treatment of a single section of a very long jet, approximating the dynamics by using periodic boundary conditions. Shear layer simulations have explored the effects of shear layers on the growth of nonlinear instabilities. Convergence of the numerical approximations has been tested by comparing jet simulations with different grid resolutions. The effects of initial conditions and geometry on the dominant disruptive instabilities have also been explored. Simulations of shear layers with a variety of thicknesses, Mach numbers and densities perturbed by incident sound waves imply that the time for the excited kink modes to grow large in amplitude and disrupt the shear layer is taug = (546 +/- 24) (M/4)^{1.7 } (Apert/0.02) ^{-0.4} delta/c, where M is the jet Mach number, delta is the half-width of the shear layer, and A_ {pert} is the perturbation amplitude. For simulations of periodic jets, the initial velocity perturbations set up zig-zag shock patterns inside the jet. In each case a single zig-zag shock pattern (an odd mode) or a double zig-zag shock pattern (an even mode) grows to dominate the flow. The dominant kink instability responsible for these shock patterns moves approximately at the linear resonance velocity, nu_ {mode} = cextnu_ {relative}/(cjet + c_ {ext}). For high resolution simulations (those with 150 or more computational zones across the jet width), the even mode dominates if the even penetration is higher in amplitude initially than the odd perturbation. For low resolution simulations, the odd mode dominates even for a stronger even mode perturbation. In high resolution simulations the jet boundary rolls up and large amounts of external gas are entrained into the jet. In low

  19. Prediction of a new class of half-metallic ferromagnets from first principles [A new class of half-metallic ferromagnets from first principles

    DOE PAGES

    Griffin, Sinead M.; Neaton, Jeffrey B.

    2017-09-12

    Half-metallic ferromagnetism (HMFM) occurs rarely in materials and yet offers great potential for spintronic devices. Recent experiments suggest a class of compounds with the `ThCrmore » $$_{2}$$Si$$_{2}$$' (122) structure -- isostructural and containing elements common with Fe pnictide-based superconductors -- can exhibit HMFM. Here we use $ab$ $initio$ density-functional theory calculations to understand the onset of half-metallicity in this family of materials and explain the appearance of ferromagnetism at a quantum critical point. We also predict new candidate materials with HMFM and high Curie temperatures through A-site alloying.« less

  20. Morphological variation and distribution of free neuromasts during half-smooth tongue sole Cynoglossus semilaevis ontogeny

    NASA Astrophysics Data System (ADS)

    Ma, Aijun; Shang, Xiaomei; Zhou, Zhou; Wang, Xin'an; Sun, Zhibin; Cui, Wenxiao; Xia, Dandan; Ma, Benhe

    2017-03-01

    This study was conducted to clarify the distribution and morphology of free neuromasts during the development of half-smooth tongue sole ( Cynoglossus semilaevis) using scanning electron microscopy. During development, (1) the apical surface of free neuromasts changed in shape from a circle to a four-point star; (2) the external structure changed from being level with the epidermis to papilla-like above the level of the epidermis; (3) the neuromast cupula changed from cylindrical to blade-shaped; (4) the free neuromasts went from occurring singly to being in clusters of a few single organs; (5) the arrangement changed from a linear array to no discernable pattern; (6) there was a significant increase in the number of free neuromasts after metamorphosis. In adult C. semilaevis, free neuromasts were only observed on the abocular side of the head. Thus, there were more free neuromasts located on the abocular side of the head with a higher concentration around the anterior nostril and mouth, which may have a mechanical sensory function to help locate food as an adaptation to a benthic mode of life.

  1. The cumulative MeHg and PCBs exposure and risk of tribal and US general population with SHEDS-multimedia

    EPA Science Inventory

    Studies have shown that the U.S. population continues to be exposed to methyl mercury (MeHg) and polychlorinated biphenyls (PCBs) due to the long half-life of those environmental contaminants. Fish intake of Tribal populations is much higher than the U.S. general population due t...

  2. Spatial Patterns of Sea Level Variability Associated with Natural Internal Climate Modes

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

    Han, Weiqing; Meehl, Gerald A.; Stammer, Detlef

    Sea level rise (SLR) can exert significant stress on highly populated coastal societies and low-lying island countries around the world. Because of this, there is huge societal demand for improved decadal predictions and future projections of SLR, particularly on a local scale along coastlines. Regionally, sea level variations can deviate considerably from the global mean due to various geophysical processes. These include changes of ocean circulations, which partially can be attributed to natural, internal modes of variability in the complex Earth’s climate system. Anthropogenic influence may also contribute to regional sea level variations. Separating the effects of natural climate modesmore » and anthropogenic forcing, however, remains a challenge and requires identification of the imprint of specific climate modes in observed sea level change patterns. In this article, we review our current state of knowledge about spatial patterns of sea level variability associated with natural climate modes on interannual-to-multidecadal timescales, with particular focus on decadal-to-multidecadal variability. Relevant climate modes and our current state of understanding their associated sea level patterns and driving mechanisms are elaborated separately for the Pacific, the Indian, the Atlantic, and the Arctic and Southern Oceans. We also discuss the issues, challenges and future outlooks for understanding the regional sea level patterns associated with climate modes. Effects of these internal modes have to be taken into account in order to achieve more reliable near-term predictions and future projections of regional SLR.« less

  3. Spatial Patterns of Sea Level Variability Associated with Natural Internal Climate Modes

    DOE PAGES

    Han, Weiqing; Meehl, Gerald A.; Stammer, Detlef; ...

    2016-10-04

    Sea level rise (SLR) can exert significant stress on highly populated coastal societies and low-lying island countries around the world. Because of this, there is huge societal demand for improved decadal predictions and future projections of SLR, particularly on a local scale along coastlines. Regionally, sea level variations can deviate considerably from the global mean due to various geophysical processes. These include changes of ocean circulations, which partially can be attributed to natural, internal modes of variability in the complex Earth’s climate system. Anthropogenic influence may also contribute to regional sea level variations. Separating the effects of natural climate modesmore » and anthropogenic forcing, however, remains a challenge and requires identification of the imprint of specific climate modes in observed sea level change patterns. In this article, we review our current state of knowledge about spatial patterns of sea level variability associated with natural climate modes on interannual-to-multidecadal timescales, with particular focus on decadal-to-multidecadal variability. Relevant climate modes and our current state of understanding their associated sea level patterns and driving mechanisms are elaborated separately for the Pacific, the Indian, the Atlantic, and the Arctic and Southern Oceans. We also discuss the issues, challenges and future outlooks for understanding the regional sea level patterns associated with climate modes. Effects of these internal modes have to be taken into account in order to achieve more reliable near-term predictions and future projections of regional SLR.« less

  4. Slow crack growth in glass in combined mode I and mode II loading

    NASA Technical Reports Server (NTRS)

    Shetty, D. K.; Rosenfield, A. R.

    1991-01-01

    Slow crack growth in soda-lime glass under combined mode I and mode II loading was investigated in precracked disk specimens in which pure mode I, pure mode II, and various combinations of mode I and mode II were achieved by loading in diametral compression at selected angles with respect to symmetric radial cracks. It is shown that slow crack growth under these conditions can be described by a simple exponential relationship with elastic strain energy release rate as the effective crack-driving force parameter. It is possible to interpret this equation in terms of theoretical models that treat subcritical crack growth as a thermally activated bond-rupture process with an activation energy dependent on the environment, and the elastic energy release rate as the crack-driving force parameter.

  5. Robust half-metallicity of hexagonal SrNiO{sub 3}

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

    Chen, Gao-Yuan; Ma, Chun-Lan, E-mail: machunlan@126.com; Chen, Da

    In the rich panorama of the electronic and magnetic properties of 3d transition metal oxides SrMO{sub 3} (M=Ti, V, Cr, Mn, Fe, Co, Ni, Cu), one member (SrNiO{sub 3}) is missing. In this paper we use GGA+U method based on density functional theory to examine its properties. It is found that SrNiO{sub 3} is a ferromagnetic half-metal. The charge density map shows a high degree of ionic bonding between Sr and other atoms. Meanwhile, a covalent-bonding Ni–O–Ni–O–Ni chain is observed. The spin density contour of SrNiO{sub 3} further indicates that the magnetic interaction between Ni atoms mediated by O ismore » semicovalent exchange. The density of states are examined to explore the unusual indirect magnetic-exchange mechanism. Corresponding to the total energies results, a robust half-metallic character is observed, suggesting a promising giant magneto-optical Kerr property of the material. The partial density of states are further examined to explore the origin of ferromagnetic half-metallicity. The O atoms are observed to have larger contribution at fermi level than Ni atoms to the spin-polarized states, demonstrating that O atoms play a critical role in ferromagnetic half-metallicity of SrNiO{sub 3}. Hydrostatic pressure effect is examined to evaluate how robust the half-metallic ferromagnetism is. - Graphical abstract: (a) The total energy as a function of the lattice constant a for hexagonal SrNiO3 with various magnetic phases. (b) The total electronic density of states for hexagonal SrNiO{sub 3} with FM configuration from GGA+U calculations. (c) Total electron-density distribution in the (110) plane. The colors gradually change from cyan (through pink) to yellow corresponding to charge density value from 0 to 4.0. (d) The magnetization density map in the (110) plane. The colors range from blue (through green) to red corresponding to magnetization density value from −0.15 to 0.45. Black and white contours stand for positive and negative values

  6. 76 FR 8651 - Special Local Regulation; Mavericks Surf Competition, Half Moon Bay, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-15

    ...-AA08 Special Local Regulation; Mavericks Surf Competition, Half Moon Bay, CA AGENCY: Coast Guard, DHS... regulation on certain navigable waters of Half Moon Bay in support of the Mavericks Surf Competition. This...,000 yard radius of Pillar Point in Half Moon Bay. The Mavericks Surf Competition will occur in the...

  7. Demand and supply-based operating modes--a framework for analyzing health care service production.

    PubMed

    Lillrank, Paul; Groop, P Johan; Malmström, Tomi J

    2010-12-01

    The structure of organizations that provide services should reflect the possibilities of and constraints on production that arise from the market segments they serve. Organizational segmentation in health care is based on urgency and severity as well as disease type, bodily function, principal method, or population subgroup. The result is conflicting priorities, goals, and performance metrics. A managerial perspective is needed to identify activities with similar requirements for integration, coordination, and control. The arguments in this article apply new reasoning to the previous literature. The method used in this article to classify health care provision distinguishes different types of health problems that share generic constraints of production. The analysis leads to seven different demand-supply combinations, each with its own operational logic. These are labeled demand and supply-based operating modes (DSO modes), and constitute the managerial building blocks of health care organizations. The modes are Prevention, Emergency, One visit, Project, Elective, Cure, and Care. As analytical categories the DSO modes can be used to understand current problems. Several operating modes in one unit create managerial problems of conflicting priorities, goals, and performance metrics. The DSO modes are constructed as managerially homogeneous categories or care platforms responding to general types of demand, and supply constraints. The DSO modes bring methods of industrial management to bear on efforts to improve health care. © 2010 Milbank Memorial Fund. Published by Wiley Periodicals Inc.

  8. Two species drag/diffusion model for energetic particle driven modes

    NASA Astrophysics Data System (ADS)

    Aslanyan, V.; Sharapov, S. E.; Spong, D. A.; Porkolab, M.

    2017-12-01

    A nonlinear bump-on-tail model for the growth and saturation of energetic particle driven plasma waves has been extended to include two populations of fast particles—one dominated by dynamical friction at the resonance and the other by velocity space diffusion. The resulting temporal evolution of the wave amplitude and frequency depends on the relative weight of the two populations. The two species model is applied to burning plasma with drag-dominated alpha particles and diffusion-dominated ICRH accelerated minority ions, showing the stabilization of bursting modes. The model also suggests an explanation for the recent observations on the TJ-II stellarator, where Alfvén Eigenmodes transition between steady state and bursting as the magnetic configuration varied.

  9. Sedentary and active: self-reported sitting time among marathon and half-marathon participants.

    PubMed

    Whitfield, Geoffrey; Pettee Gabriel, Kelley K; Kohl, Harold William

    2014-01-01

    Emerging evidence suggests that combined physical activity (PA) and inactivity may be more important for chronic disease risk than PA alone. A highly active yet highly sedentary population is needed to study this interaction. The present purpose is to describe the sitting habits of a group of recreational runners and determine if sitting varies with reported training duration or anticipated running velocity. Marathon and half-marathon participants completed the Multicontext Sitting Time Questionnaire and reported peak training duration, anticipated finishing time, and demographic information. Sitting time was described across 5 contexts for workdays and nonworkdays. Total sitting time was analyzed by tertiles of training duration and anticipated event running velocity. 218 participants took part in this study. Median reported training time was 6.5 hours per week. Median total sitting time was higher on workdays than nonworkdays (645 and 480 minutes, respectively, P < .0001). Total sitting time was not associated with training duration or anticipated event running velocity. These results suggest that recreational distance runners are simultaneously highly sedentary and highly active, supporting independence of sedentary behaviors and moderate- to vigorous-intensity PA. This population may provide the characteristics needed to study the joint effects of active and sedentary behaviors on health outcomes.

  10. Determination of the energy transitions and half-lives of Rubidium nuclei

    NASA Astrophysics Data System (ADS)

    Biçer, Ahmet; Manisa, Kaan; Engin Çalık, Abdullah; Erdoğan, Mehmet; Şen, Mürsel; Bircan, Hasan; Dapo, Haris; Boztosun, Ismail

    2018-03-01

    The photonuclear reactions, first extensively studied in the 1970's and performed using the gamma rays obtained via bremsstrahlung, are a standard nuclear physics experiment. In this study, a non-enriched Rubidium sample was irradiated with photons produced by a clinical linear electron accelerator (cLINACs) with energies up to 18 MeV with the aim of activating it through photonuclear reactions. The activated sample was measured with a high purity germanium detector (HPGe) with the aim of measuring the transition energies and half-lives. The spectroscopic analysis performed on the obtained data yielded high quality results for the transition energies with precision matching or surpassing the literature data. For the half-lives the results were consistent with the literature, most notably the half-life of 84mRb decay was determined as 20.28(2) m. The results for both energies and half-lives further show that the clinical linear accelerators can be successfully used as an efficient tool in experimental nuclear research endeavors.

  11. Comparison of detectability in step-and-shoot mode and continuous mode digital tomosynthesis systems

    NASA Astrophysics Data System (ADS)

    Lee, Changwoo; Han, Minah; Baek, Jongduk

    2017-03-01

    Digital tomosynthesis system has been widely used in chest, dental, and breast imaging. Since the digital tomosynthesis system provides volumetric images from multiple projection data, structural noise inherent in X-ray radiograph can be reduced, and thus signal detection performance is improved. Currently, tomosynthesis system uses two data acquisition modes: step-and-shoot mode and continuous mode. Several studies have been conducted to compare the system performance of two acquisition modes with respect to spatial resolution and contrast. In this work, we focus on signal detectability in step-and-shoot mode and continuous mode. For evaluation, uniform background is considered, and eight spherical objects with diameters of 0.5, 0.8, 1, 2, 3, 5, 8, 10 mm are used as signals. Projection data with and without spherical objects are acquired in step-and-shoot mode and continuous mode, respectively, and quantum noise are added. Then, noisy projection data are reconstructed by FDK algorithm. To compare the detection performance of two acquisition modes, we calculate task signal-to-noise ratio (SNR) of channelized Hotelling observer with Laguerre-Gauss channels for each spherical object. While the task-SNR values of two acquisition modes are similar for spherical objects larger than 1 mm diameter, step-and-shoot mode yields higher detectability for small signal sizes. The main reason of this behavior is that small signal is more affected by X-ray tube motion blur than large signal. Our results indicate that it is beneficial to use step-and-shoot data acquisition mode to improve the detectability of small signals (i.e., less than 1 mm diameter) in digital tomosynthesis systems.

  12. Processing mode during repetitive thinking in socially anxious individuals: evidence for a maladaptive experiential mode.

    PubMed

    Wong, Quincy J J; Moulds, Michelle L

    2012-12-01

    Evidence from the depression literature suggests that an analytical processing mode adopted during repetitive thinking leads to maladaptive outcomes relative to an experiential processing mode. To date, in socially anxious individuals, the impact of processing mode during repetitive thinking related to an actual social-evaluative situation has not been investigated. We thus tested whether an analytical processing mode would be maladaptive relative to an experiential processing mode during anticipatory processing and post-event rumination. High and low socially anxious participants were induced to engage in either an analytical or experiential processing mode during: (a) anticipatory processing before performing a speech (Experiment 1; N = 94), or (b) post-event rumination after performing a speech (Experiment 2; N = 74). Mood, cognition, and behavioural measures were employed to examine the effects of processing mode. For high socially anxious participants, the modes had a similar effect on self-reported anxiety during both anticipatory processing and post-event rumination. Unexpectedly, relative to the analytical mode, the experiential mode led to stronger high standard and conditional beliefs during anticipatory processing, and stronger unconditional beliefs during post-event rumination. These experiments are the first to investigate processing mode during anticipatory processing and post-event rumination. Hence, these results are novel and will need to be replicated. These findings suggest that an experiential processing mode is maladaptive relative to an analytical processing mode during repetitive thinking characteristic of socially anxious individuals. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Pad-mode-induced instantaneous mode instability for simple models of brake systems

    NASA Astrophysics Data System (ADS)

    Oberst, S.; Lai, J. C. S.

    2015-10-01

    Automotive disc brake squeal is fugitive, transient and remains difficult to predict. In particular, instantaneous mode squeal observed experimentally does not seem to be associated with mode coupling and its mechanism is not clear. The effects of contact pressures, friction coefficients as well as material properties (pressure and temperature dependency and anisotropy) for brake squeal propensity have not been systematically explored. By analysing a finite element model of an isotropic pad sliding on a plate similar to that of a previously reported experimental study, pad modes have been identified and found to be stable using conventional complex eigenvalue analysis. However, by subjecting the model to contact pressure harmonic excitation for a range of pressures and friction coefficients, a forced response analysis reveals that the dissipated energy for pad modes is negative and becomes more negative with increasing contact pressures and friction coefficients, indicating the potential for instabilities. The frequency of the pad mode in the sliding direction is within the range of squeal frequencies observed experimentally. Nonlinear time series analysis of the vibration velocity also confirms the evolution of instabilities induced by pad modes as the friction coefficient increases. By extending this analysis to a more realistic but simple brake model in the form of a pad-on-disc system, in-plane pad-modes, which a complex eigenvalue analysis predicts to be stable, have also been identified by negative dissipated energy for both isotropic and anisotropic pad material properties. The influence of contact pressures on potential instabilities has been found to be more dominant than changes in material properties owing to changes in pressure or temperature. Results here suggest that instantaneous mode squeal is likely caused by in-plane pad-mode instabilities.

  14. Delineation of separate brain regions used for scientific versus engineering modes of thinking

    NASA Astrophysics Data System (ADS)

    Patterson, Clair C.

    1994-08-01

    Powerful, latent abilities for extreme sophistication in abstract rationalization as potential biological adaptive behavioral responses were installed entirely through accident and inadvertence by biological evolution in the Homo sapiens sapiens species of brain. These potentials were never used, either in precursor species as factors in evolutionary increase in hominid brain mass, nor in less sophisticated forms within social environments characterized by Hss tribal brain population densities. Those latent abilities for unnatural biological adaptive behavior were forced to become manifest in various ways by growths in sophistication of communication interactions engendered by large growths in brain population densities brought on by developments in agriculture at the onset of the Holocene. It is proposed that differences probably exist between regions of the Hss brain involved in utilitarian, engineering types of problem conceptualization-solving versus regions of the brain involved in nonutilitarian, artistic-scientific types of problem conceptualization-solving. Populations isolated on separate continents from diffusive contact and influence on cultural developments, and selected for comparison of developments during equivalent stages of technological and social sophistication in matching 4000 year periods, show, at the ends of those periods, marked differences in aesthetic attributes expressed in cosmogonies, music, and writing (nonutilitarian thinking related to science and art). On the other hand the two cultures show virtually identical developments in three major stages of metallurgical technologies (utilitarian thinking related to engineering). Such archaeological data suggest that utilitarian modes of thought may utilize combinations of neuronal circuits in brain regions that are conserved among tribal populations territorially separated from each other for tens of thousands of years. Such conservation may not be true for neuronal circuits involved in

  15. Prediction of half-marathon race time in recreational female and male runners.

    PubMed

    Knechtle, Beat; Barandun, Ursula; Knechtle, Patrizia; Zingg, Matthias A; Rosemann, Thomas; Rüst, Christoph A

    2014-01-01

    Half-marathon running is of high popularity. Recent studies tried to find predictor variables for half-marathon race time for recreational female and male runners and to present equations to predict race time. The actual equations included running speed during training for both women and men as training variable but midaxillary skinfold for women and body mass index for men as anthropometric variable. An actual study found that percent body fat and running speed during training sessions were the best predictor variables for half-marathon race times in both women and men. The aim of the present study was to improve the existing equations to predict half-marathon race time in a larger sample of male and female half-marathoners by using percent body fat and running speed during training sessions as predictor variables. In a sample of 147 men and 83 women, multiple linear regression analysis including percent body fat and running speed during training units as independent variables and race time as dependent variable were performed and an equation was evolved to predict half-marathon race time. For men, half-marathon race time might be predicted by the equation (r(2) = 0.42, adjusted r(2) = 0.41, SE = 13.3) half-marathon race time (min) = 142.7 + 1.158 × percent body fat (%) - 5.223 × running speed during training (km/h). The predicted race time correlated highly significantly (r = 0.71, p < 0.0001) to the achieved race time. For women, half-marathon race time might be predicted by the equation (r(2) = 0.68, adjusted r(2) = 0.68, SE = 9.8) race time (min) = 168.7 + 1.077 × percent body fat (%) - 7.556 × running speed during training (km/h). The predicted race time correlated highly significantly (r = 0.89, p < 0.0001) to the achieved race time. The coefficients of determination of the models were slightly higher than for the existing equations. Future studies might include physiological

  16. A randomised trial and economic evaluation of the effect of response mode on response rate, response bias, and item non-response in a survey of doctors.

    PubMed

    Scott, Anthony; Jeon, Sung-Hee; Joyce, Catherine M; Humphreys, John S; Kalb, Guyonne; Witt, Julia; Leahy, Anne

    2011-09-05

    Surveys of doctors are an important data collection method in health services research. Ways to improve response rates, minimise survey response bias and item non-response, within a given budget, have not previously been addressed in the same study. The aim of this paper is to compare the effects and costs of three different modes of survey administration in a national survey of doctors. A stratified random sample of 4.9% (2,702/54,160) of doctors undertaking clinical practice was drawn from a national directory of all doctors in Australia. Stratification was by four doctor types: general practitioners, specialists, specialists-in-training, and hospital non-specialists, and by six rural/remote categories. A three-arm parallel trial design with equal randomisation across arms was used. Doctors were randomly allocated to: online questionnaire (902); simultaneous mixed mode (a paper questionnaire and login details sent together) (900); or, sequential mixed mode (online followed by a paper questionnaire with the reminder) (900). Analysis was by intention to treat, as within each primary mode, doctors could choose either paper or online. Primary outcome measures were response rate, survey response bias, item non-response, and cost. The online mode had a response rate 12.95%, followed by the simultaneous mixed mode with 19.7%, and the sequential mixed mode with 20.7%. After adjusting for observed differences between the groups, the online mode had a 7 percentage point lower response rate compared to the simultaneous mixed mode, and a 7.7 percentage point lower response rate compared to sequential mixed mode. The difference in response rate between the sequential and simultaneous modes was not statistically significant. Both mixed modes showed evidence of response bias, whilst the characteristics of online respondents were similar to the population. However, the online mode had a higher rate of item non-response compared to both mixed modes. The total cost of the online

  17. A randomised trial and economic evaluation of the effect of response mode on response rate, response bias, and item non-response in a survey of doctors

    PubMed Central

    2011-01-01

    Background Surveys of doctors are an important data collection method in health services research. Ways to improve response rates, minimise survey response bias and item non-response, within a given budget, have not previously been addressed in the same study. The aim of this paper is to compare the effects and costs of three different modes of survey administration in a national survey of doctors. Methods A stratified random sample of 4.9% (2,702/54,160) of doctors undertaking clinical practice was drawn from a national directory of all doctors in Australia. Stratification was by four doctor types: general practitioners, specialists, specialists-in-training, and hospital non-specialists, and by six rural/remote categories. A three-arm parallel trial design with equal randomisation across arms was used. Doctors were randomly allocated to: online questionnaire (902); simultaneous mixed mode (a paper questionnaire and login details sent together) (900); or, sequential mixed mode (online followed by a paper questionnaire with the reminder) (900). Analysis was by intention to treat, as within each primary mode, doctors could choose either paper or online. Primary outcome measures were response rate, survey response bias, item non-response, and cost. Results The online mode had a response rate 12.95%, followed by the simultaneous mixed mode with 19.7%, and the sequential mixed mode with 20.7%. After adjusting for observed differences between the groups, the online mode had a 7 percentage point lower response rate compared to the simultaneous mixed mode, and a 7.7 percentage point lower response rate compared to sequential mixed mode. The difference in response rate between the sequential and simultaneous modes was not statistically significant. Both mixed modes showed evidence of response bias, whilst the characteristics of online respondents were similar to the population. However, the online mode had a higher rate of item non-response compared to both mixed modes. The

  18. Psychosocial correlates of unintentional weight loss in the second half of life in the German general population

    PubMed Central

    König, Hans-Helmut

    2017-01-01

    Background Unintentional weight loss (UWL) is common in older age and associated with adverse outcomes including mortality. The aim of the present study was to determine psychosocial correlates of UWL. Methods Data were derived from a large, nationally representative study of community-dwelling individuals in the second half of life (40 years and over) in Germany in 2014 (n = 7,933). Data on UWL were assessed in face-to-face interviews as unintentional loss of more than 5kg (11 pounds) in weight in the past 12 months, and data on psychosocial factors were recorded in self-administered questionnaires. Results Multiple logistic regressions revealed that UWL was positively associated with depressive symptoms and positive affect, whereas it was negatively associated with self-esteem. Individuals with UWL were more likely to feel lonely and perceive themselves as socially excluded. Conclusion The findings of important psychosocial correlates of UWL may help to identify individuals at risk for UWL in older age. This is in particular important since interventions to treat this phenomenon in older age are available that reduce adverse consequences resulting from UWL. PMID:28968437

  19. The Integrated Mode Management Interface

    NASA Technical Reports Server (NTRS)

    Hutchins, Edwin

    1996-01-01

    Mode management is the processes of understanding the character and consequences of autoflight modes, planning and selecting the engagement, disengagement and transitions between modes, and anticipating automatic mode transitions made by the autoflight system itself. The state of the art is represented by the latest designs produced by each of the major airframe manufacturers, the Boeing 747-400, the Boeing 777, the McDonnell Douglas MD-11, and the Airbus A320/A340 family of airplanes. In these airplanes autoflight modes are selected by manipulating switches on the control panel. The state of the autoflight system is displayed on the flight mode annunciators. The integrated mode management interface (IMMI) is a graphical interface to autoflight mode management systems for aircraft equipped with flight management computer systems (FMCS). The interface consists of a vertical mode manager and a lateral mode manager. Autoflight modes are depicted by icons on a graphical display. Mode selection is accomplished by touching (or mousing) the appropriate icon. The IMMI provides flight crews with an integrated interface to autoflight systems for aircraft equipped with flight management computer systems (FMCS). The current version is modeled on the Boeing glass-cockpit airplanes (747-400, 757/767). It runs on the SGI Indigo workstation. A working prototype of this graphics-based crew interface to the autoflight mode management tasks of glass cockpit airplanes has been installed in the Advanced Concepts Flight Simulator of the CSSRF of NASA Ames Research Center. This IMMI replaces the devices in FMCS equipped airplanes currently known as mode control panel (Boeing), flight guidance control panel (McDonnell Douglas), and flight control unit (Airbus). It also augments the functions of the flight mode annunciators. All glass cockpit airplanes are sufficiently similar that the IMMI could be tailored to the mode management system of any modern cockpit. The IMMI does not replace the

  20. Impact of pacemaker mode in patients with atrioventricular conduction disturbance after trans-catheter aortic valve implantation.

    PubMed

    Takahashi, Masao; Badenco, Nicolas; Monteau, Jacques; Gandjbakhch, Estelle; Extramiana, Fabrice; Urena, Marina; Karam, Nicole; Marijon, Eloi; Algalarrondo, Vincent; Teiger, Emmanuel; Lellouche, Nicolas

    2018-03-14

    This study aimed to assess the impact of pacemaker mode programming on clinical outcomes in patients with high-degree atrioventricular conduction disturbance (AVCD) after transcatheter aortic valve implantation (TAVI). Although high-degree AVCD after TAVI can receive pacemaker, recovery of the AVCD is often observed. Specific pacemaker algorithms (AAI-DDD mode switch) are available which favor spontaneous atrioventricular conduction. Of 1,621 consecutive multi-center TAVI patients, 269 (16.4%) received pacemaker. We retrospectively included 91 patients with persistent high-degree AVCD at hospital discharge. Pacemaker dependency was defined as absence, inadequate intrinsic ventricular rhythm, or ventricular pacing time > 95% on pacemaker interrogation during follow-up. Comparison of heart failure hospitalization and death between conventional DDD (cDDD) and other modes was examined (AAI-DDD and VVI). During a mean follow-up duration of 13 months, the pacemaker dependency rate was 52.8%. Patients with cDDD mode (N = 36: 40.0%) had significantly more pacemaker dependency. Multivariate analysis showed that cDDD mode was independently associated with pacemaker dependency (odds ratio = 3.63, P = 0.03). Moreover, cDDD patients had a significant higher incidence of heart failure hospitalization (Hospitalization: cDDD vs. others = 45.4% vs. 18.2%, P = 0.03) and had a higher incidence of mortality (Death: cDDD vs. the others = 27.0% vs. 4.4%, P = 0.06). Up to half of patients implanted for high-degree AVCD after TAVI had conduction recovery. Patients with cDDD programming at hospital discharge had more pacemaker dependency and a worse cardiac prognosis. Thus, pacemaker mode should be systematically set to promote spontaneous atrioventricular conduction in patients with pacemaker implantation after TAVI. © 2018 Wiley Periodicals, Inc.

  1. Relating normal vibrational modes to local vibrational modes with the help of an adiabatic connection scheme

    NASA Astrophysics Data System (ADS)

    Zou, Wenli; Kalescky, Robert; Kraka, Elfi; Cremer, Dieter

    2012-08-01

    Information on the electronic structure of a molecule and its chemical bonds is encoded in the molecular normal vibrational modes. However, normal vibrational modes result from a coupling of local vibrational modes, which means that only the latter can provide detailed insight into bonding and other structural features. In this work, it is proven that the adiabatic internal coordinate vibrational modes of Konkoli and Cremer [Int. J. Quantum Chem. 67, 29 (1998)], 10.1002/(SICI)1097-461X(1998)67:1<29::AID-QUA3>3.0.CO;2-0 represent a unique set of local modes that is directly related to the normal vibrational modes. The missing link between these two sets of modes are the compliance constants of Decius, which turn out to be the reciprocals of the local mode force constants of Konkoli and Cremer. Using the compliance constants matrix, the local mode frequencies of any molecule can be converted into its normal mode frequencies with the help of an adiabatic connection scheme that defines the coupling of the local modes in terms of coupling frequencies and reveals how avoided crossings between the local modes lead to changes in the character of the normal modes.

  2. Dendritic Slow Dynamics Enables Localized Cortical Activity to Switch between Mobile and Immobile Modes with Noisy Background Input

    PubMed Central

    Kurashige, Hiroki; Câteau, Hideyuki

    2011-01-01

    Mounting lines of evidence suggest the significant computational ability of a single neuron empowered by active dendritic dynamics. This motivates us to study what functionality can be acquired by a network of such neurons. The present paper studies how such rich single-neuron dendritic dynamics affects the network dynamics, a question which has scarcely been specifically studied to date. We simulate neurons with active dendrites networked locally like cortical pyramidal neurons, and find that naturally arising localized activity – called a bump – can be in two distinct modes, mobile or immobile. The mode can be switched back and forth by transient input to the cortical network. Interestingly, this functionality arises only if each neuron is equipped with the observed slow dendritic dynamics and with in vivo-like noisy background input. If the bump activity is considered to indicate a point of attention in the sensory areas or to indicate a representation of memory in the storage areas of the cortex, this would imply that the flexible mode switching would be of great potential use for the brain as an information processing device. We derive these conclusions using a natural extension of the conventional field model, which is defined by combining two distinct fields, one representing the somatic population and the other representing the dendritic population. With this tool, we analyze the spatial distribution of the degree of after-spike adaptation and explain how we can understand the presence of the two distinct modes and switching between the modes. We also discuss the possible functional impact of this mode-switching ability. PMID:21931635

  3. Coupling analysis of non-circular-symmetric modes and design of orientation-insensitive few-mode fiber couplers

    NASA Astrophysics Data System (ADS)

    Li, Jiaxiong; Du, Jiangbing; Ma, Lin; Li, Ming-Jun; Jiang, Shoulin; Xu, Xiao; He, Zuyuan

    2017-01-01

    We study the coupling between two identical weakly-coupled few-mode fibers based on coupled-mode theory. The coupling behavior of non-circular-symmetric modes, such as LP11 and LP21, is investigated analytically and numerically. By carefully choosing the fiber core separation and coupler length, we can design orientation-insensitive fiber couplers for non-circular-symmetric modes at arbitrary coupling ratios. Based on the design method, we propose an orientation-insensitive two-mode fiber coupler at 850 nm working as a mode multiplexer/demultiplexer for two-mode transmission using standard single-mode fiber. Within the band from 845 to 855 nm, the insertion losses of LP01 and LP11 modes are less than 0.03 dB and 0.24 dB, respectively. When the two-mode fiber coupler is used as mode demultiplexer, the LP01/LP11 and LP11/LP01 extinction ratios in the separated branches are respectively above 12.6 dB and 21.2 dB. Our design method can be extended to two-mode communication or sensing systems at other wavelengths.

  4. Population Structure and History in Developing Core Sets in Wild Germplasm

    USDA-ARS?s Scientific Manuscript database

    Accurate inference of genetic discontinuities between populations is an essential component in studies of intraspecific biodiversity and evolution, as well as associative genetics. Multi-locus genotypes were amplified from 949 individuals representing seedling trees from 88 half-sib families from ei...

  5. Population Structure And History In Developing Core Sets In Wild Germplasm.

    USDA-ARS?s Scientific Manuscript database

    Accurate inference of genetic discontinuities between populations is an essential component in studies of intraspecific biodiversity and evolution, as well as associative genetics. Multi-locus genotypes were amplified from 949 individuals representing seedling trees from 88 half-sib families from ei...

  6. Moving target detection in flash mode against stroboscopic mode by active range-gated laser imaging

    NASA Astrophysics Data System (ADS)

    Zhang, Xuanyu; Wang, Xinwei; Sun, Liang; Fan, Songtao; Lei, Pingshun; Zhou, Yan; Liu, Yuliang

    2018-01-01

    Moving target detection is important for the application of target tracking and remote surveillance in active range-gated laser imaging. This technique has two operation modes based on the difference of the number of pulses per frame: stroboscopic mode with the accumulation of multiple laser pulses per frame and flash mode with a single shot of laser pulse per frame. In this paper, we have established a range-gated laser imaging system. In the system, two types of lasers with different frequency were chosen for the two modes. Electric fan and horizontal sliding track were selected as the moving targets to compare the moving blurring between two modes. Consequently, the system working in flash mode shows more excellent performance in motion blurring against stroboscopic mode. Furthermore, based on experiments and theoretical analysis, we presented the higher signal-to-noise ratio of image acquired by stroboscopic mode than flash mode in indoor and underwater environment.

  7. The Other Half of the Embodied Mind

    PubMed Central

    Parisi, Domenico

    2011-01-01

    Embodied theories of mind tend to be theories of the cognitive half of the mind and to ignore its emotional half while a complete theory of the mind should account for both halves. Robots are a new way of expressing theories of the mind which are less ambiguous and more capable to generate specific and non-controversial predictions than verbally expressed theories. We outline a simple robotic model of emotional states as states of a sub-part of the neural network controlling the robot's behavior which has specific properties and which allows the robot to make faster and more correct motivational decisions, and we describe possible extensions of the model to account for social emotional states and for the expression of emotions that, unlike those of current “emotional” robots, are really “felt” by the robot in that they play a well-identified functional role in the robot's behavior. PMID:21687441

  8. Population limitation and the wolves of Isle Royale

    USGS Publications Warehouse

    Peterson, Rolf O.; Thomas, Nancy J.; Thurber, Joanne M.; Vucetich, John A.; Waite, Thomas A.

    1998-01-01

    Population regulation for gray wolves in Isle Royale National Park, Michigan, was examined in 1987-1995 when wolves were in chronic decline following a crash of the population in 1981-1982. Canine parvovirus (CPV-2) was probably influential during the crash, but it disappeared by the late 1980s. High mortality abruptly ceased after 1988, but low recruitment in the absence of disease and obvious shortage of food prevented recovery of the wolf population. In 1983-1995, with a comparable number of moose '10 years old as potential prey, wolves were only half as numerous as in 1959-1980. A simulation of annual fluctuations in effective population size (Ne) for wolves on Isle Royale suggests that their genetic heterozygosity has declined ca. 13% with each generation and ca. 80% in the 50- year history of this population. Inbreeding depression and stochastic demographic variation both remain possible explanations for recent low recruitment.

  9. Slots in dielectric image line as mode launchers and circuit elements

    NASA Astrophysics Data System (ADS)

    Solbach, K.

    1981-01-01

    A planar resonator model is used to investigate slots in the ground plane of dielectric image lines. An equivalent circuit representation of the slot discontinuity is obtained, and the launching efficiency of the slot as a mode launcher is analyzed. Slots are also shown to be useful in the realization of dielectric image line array antennas. It is found that the slot discontinuity can be shown as a T-junction of the dielectric image line and a metal waveguide. The launching efficiency is found to increase with the dielectric constant of the dielectric image line, exhibiting a maximum value for guides whose height is slightly less than half a wavelength in the dielectric medium. The measured launching efficiencies of low permittivity dielectric image lines are found to be in good agreement with calculated values

  10. The Aerosol Coarse Mode Initiative

    NASA Astrophysics Data System (ADS)

    Arnott, W. P.; Adhikari, N.; Air, D.; Kassianov, E.; Barnard, J.

    2014-12-01

    Many areas of the world show an aerosol volume distribution with a significant coarse mode and sometimes a dominant coarse mode. The large coarse mode is usually due to dust, but sea salt aerosol can also play an important role. However, in many field campaigns, the coarse mode tends to be ignored, because it is difficult to measure. This lack of measurements leads directly to a concomitant "lack of analysis" of this mode. Because, coarse mode aerosols can have significant effects on radiative forcing, both in the shortwave and longwave spectrum, the coarse mode -- and these forcings -- should be accounted for in atmospheric models. Forcings based only on fine mode aerosols have the potential to be misleading. In this paper we describe examples of large coarse modes that occur in areas of large aerosol loading (Mexico City, Barnard et al., 2010) as well as small loadings (Sacramento, CA; Kassianov et al., 2012; and Reno, NV). We then demonstrate that: (1) the coarse mode can contribute significantly to radiative forcing, relative to the fine mode, and (2) neglecting the coarse mode may result in poor comparisons between measurements and models. Next we describe -- in general terms -- the limitations of instrumentation to measure the coarse mode. Finally, we suggest a new initiative aimed at examining coarse mode aerosol generation mechanisms; transport and deposition; chemical composition; visible and thermal IR refractive indices; morphology; microphysical behavior when deposited on snow and ice; and specific instrumentation needs. Barnard, J. C., J. D. Fast, G. Paredes-Miranda, W. P. Arnott, and A. Laskin, 2010: Technical Note: Evaluation of the WRF-Chem "Aerosol Chemical to Aerosol Optical Properties" Module using data from the MILAGRO campaign, Atmospheric Chemistry and Physics, 10, 7325-7340. Kassianov, E. I., M. S. Pekour, and J. C. Barnard, 2012: Aerosols in Central California: Unexpectedly large contribution of coarse mode to aerosol radiative forcing

  11. Structured light generation by magnetic metamaterial half-wave plates at visible wavelength

    NASA Astrophysics Data System (ADS)

    Zeng, Jinwei; Luk, Ting S.; Gao, Jie; Yang, Xiaodong

    2017-12-01

    Metamaterial or metasurface unit cells functioning as half-wave plates play an essential role for realizing ideal Pancharatnam-Berry phase optical elements capable of tailoring light phase and polarization as desired. Complex light beam manipulation through these metamaterials or metasurfaces unveils new dimensions of light-matter interactions for many advances in diffraction engineering, beam shaping, structuring light, and holography. However, the realization of metamaterial or metasurface half-wave plates in visible spectrum range is still challenging mainly due to its specific requirements of strong phase anisotropy with amplitude isotropy in subwavelength scale. Here, we propose magnetic metamaterial structures which can simultaneously exploit the electric field and magnetic field of light for achieving the nanoscale half-wave plates at visible wavelength. We design and demonstrate the magnetic metamaterial half-wave plates in linear grating patterns with high polarization conversion purity in a deep subwavelength thickness. Then, we characterize the equivalent magnetic metamaterial half-wave plates in cylindrical coordinate as concentric-ring grating patterns, which act like an azimuthal half-wave plate and accordingly exhibit spatially inhomogeneous polarization and phase manipulations including spin-to-orbital angular momentum conversion and vector beam generation. Our results show potentials for realizing on-chip beam converters, compact holograms, and many other metamaterial devices for structured light beam generation, polarization control, and wavefront manipulation.

  12. Predictor variables for a half marathon race time in recreational male runners

    PubMed Central

    Rüst, Christoph Alexander; Knechtle, Beat; Knechtle, Patrizia; Barandun, Ursula; Lepers, Romuald; Rosemann, Thomas

    2011-01-01

    The aim of this study was to investigate predictor variables of anthropometry, training, and previous experience in order to predict a half marathon race time for future novice recreational male half marathoners. Eighty-four male finishers in the ‘Half Marathon Basel’ completed the race distance within (mean and standard deviation, SD) 103.9 (16.5) min, running at a speed of 12.7 (1.9) km/h. After multivariate analysis of the anthropometric characteristics, body mass index (r = 0.56), suprailiacal (r = 0.36) and medial calf skin fold (r = 0.53) were related to race time. For the variables of training and previous experience, speed in running of the training sessions (r = −0.54) were associated with race time. After multivariate analysis of both the significant anthropometric and training variables, body mass index (P = 0.0150) and speed in running during training (P = 0.0045) were related to race time. Race time in a half marathon might be partially predicted by the following equation (r2 = 0.44): Race time (min) = 72.91 + 3.045 * (body mass index, kg/m2) −3.884 * (speed in running during training, km/h) for recreational male runners. To conclude, variables of both anthropometry and training were related to half marathon race time in recreational male half marathoners and cannot be reduced to one single predictor variable. PMID:24198577

  13. Predictor variables for a half marathon race time in recreational male runners.

    PubMed

    Rüst, Christoph Alexander; Knechtle, Beat; Knechtle, Patrizia; Barandun, Ursula; Lepers, Romuald; Rosemann, Thomas

    2011-01-01

    The aim of this study was to investigate predictor variables of anthropometry, training, and previous experience in order to predict a half marathon race time for future novice recreational male half marathoners. Eighty-four male finishers in the 'Half Marathon Basel' completed the race distance within (mean and standard deviation, SD) 103.9 (16.5) min, running at a speed of 12.7 (1.9) km/h. After multivariate analysis of the anthropometric characteristics, body mass index (r = 0.56), suprailiacal (r = 0.36) and medial calf skin fold (r = 0.53) were related to race time. For the variables of training and previous experience, speed in running of the training sessions (r = -0.54) were associated with race time. After multivariate analysis of both the significant anthropometric and training variables, body mass index (P = 0.0150) and speed in running during training (P = 0.0045) were related to race time. Race time in a half marathon might be partially predicted by the following equation (r(2) = 0.44): Race time (min) = 72.91 + 3.045 * (body mass index, kg/m(2)) -3.884 * (speed in running during training, km/h) for recreational male runners. To conclude, variables of both anthropometry and training were related to half marathon race time in recreational male half marathoners and cannot be reduced to one single predictor variable.

  14. Vibration mode and vibration shape under excitation of a three phase model transformer core

    NASA Astrophysics Data System (ADS)

    Okabe, Seiji; Ishigaki, Yusuke; Omura, Takeshi

    2018-04-01

    Structural vibration characteristics and vibration shapes under three-phase excitation of a archetype transformer core were investigated to consider their influences on transformer noise. Acoustic noise and vibration behavior were measured in a three-limb model transformer core. Experimental modal analysis by impact test was performed. The vibration shapes were measured by a laser scanning vibrometer at different exciting frequencies. Vibration amplitude of the core in out-of-plane direction were relatively larger than those in other two in-plane directions. It was consistent with the result that the frequency response function of the core in out-of-plane direction was larger by about 20 dB or more than those in in-plane directions. There were many vibration modes having bending deformation of limbs in out-of-plane direction. The vibration shapes of the core when excited at 50 Hz and 60 Hz were almost the same because the fundamental frequencies of the vibration were not close to the resonance frequencies. When excitation frequency was 69 Hz which was half of one of the resonance frequencies, the vibration shape changed to the one similar to the resonance vibration mode. Existence of many vibration modes in out-of-plane direction of the core was presumed to be a reason why frequency characteristics of magnetostriction and transformer noise do not coincide.

  15. An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm.

    PubMed

    Dinerstein, Eric; Olson, David; Joshi, Anup; Vynne, Carly; Burgess, Neil D; Wikramanayake, Eric; Hahn, Nathan; Palminteri, Suzanne; Hedao, Prashant; Noss, Reed; Hansen, Matt; Locke, Harvey; Ellis, Erle C; Jones, Benjamin; Barber, Charles Victor; Hayes, Randy; Kormos, Cyril; Martin, Vance; Crist, Eileen; Sechrest, Wes; Price, Lori; Baillie, Jonathan E M; Weeden, Don; Suckling, Kierán; Davis, Crystal; Sizer, Nigel; Moore, Rebecca; Thau, David; Birch, Tanya; Potapov, Peter; Turubanova, Svetlana; Tyukavina, Alexandra; de Souza, Nadia; Pintea, Lilian; Brito, José C; Llewellyn, Othman A; Miller, Anthony G; Patzelt, Annette; Ghazanfar, Shahina A; Timberlake, Jonathan; Klöser, Heinz; Shennan-Farpón, Yara; Kindt, Roeland; Lillesø, Jens-Peter Barnekow; van Breugel, Paulo; Graudal, Lars; Voge, Maianna; Al-Shammari, Khalaf F; Saleem, Muhammad

    2017-06-01

    We assess progress toward the protection of 50% of the terrestrial biosphere to address the species-extinction crisis and conserve a global ecological heritage for future generations. Using a map of Earth's 846 terrestrial ecoregions, we show that 98 ecoregions (12%) exceed Half Protected; 313 ecoregions (37%) fall short of Half Protected but have sufficient unaltered habitat remaining to reach the target; and 207 ecoregions (24%) are in peril, where an average of only 4% of natural habitat remains. We propose a Global Deal for Nature-a companion to the Paris Climate Deal-to promote increased habitat protection and restoration, national- and ecoregion-scale conservation strategies, and the empowerment of indigenous peoples to protect their sovereign lands. The goal of such an accord would be to protect half the terrestrial realm by 2050 to halt the extinction crisis while sustaining human livelihoods.

  16. On the stability of nongyrotropic ion populations - A first (analytic and simulation) assessment

    NASA Technical Reports Server (NTRS)

    Brinca, A. L.; Borda De Agua, L.; Winske, D.

    1993-01-01

    The wave and dispersion equations for perturbations propagating parallel to an ambient magnetic field in magnetoplasmas with nongyrotropic ion populations show, in general, the occurrence of coupling between the parallel (left- and right-hand circularly polarized electromagnetic and longitudinal electrostatic) eigenmodes of the associated gyrotropic medium. These interactions provide a means to driving linearly one mode with free-energy sources of other modes in homogeneous media. Different types of nongyrotropy bring about distinct classes of coupling. The stability of a hydrogen magnetoplasma with anisotropic, nongyrotropic protons that only couple the electromagnetic modes to each other is investigated analytically (via solution of the derived dispersion equation) and numerically (via simulation with a hybrid code). Nongyrotropy enhances growth and enlarges the unstable spectral range relative to the corresponding gyrotropic situation. The relevance of the properties of nongyrotropic populations to space plasma environments is also discussed.

  17. Variation in absorption and half-life of hydrocortisone influence plasma cortisol concentrations.

    PubMed

    Hindmarsh, Peter C; Charmandari, Evangelia

    2015-04-01

    Hydrocortisone therapy should be individualized in congenital adrenal hyperplasia (CAH) patients to avoid over and under replacement. We have assessed how differences in absorption and half-life of cortisol influence glucocorticoid exposure. Forty-eight patients (21 M) aged between 6·1 and 20·3 years with CAH due to CYP21A2 deficiency were studied. Each patient underwent a 24-h plasma cortisol profile with the morning dose used to calculate absorption parameters along with an intravenous (IV) hydrocortisone (15 mg/m(2) body surface area) bolus assessment of half-life. Parameters derived were maximum plasma concentration (Cmax ), time of maximum plasma concentration (tmax ), time to attaining plasma cortisol concentration <100 nmol/l and half-life of cortisol. Mean half-life was 76·5 ± 5·2 (range 40-225·3) min, Cmax 780·7 ± 61·6 nmol/l and tmax 66·7 (range 20-118) min. Time taken to a plasma cortisol concentration less than 100 nmol/l was 289 (range 140-540) min. Those with a fast half-life and slow tmax took longest to reach a plasma cortisol concentration less than 100 nmol/l (380 ± 34·6 min), compared to those with a slow half-life and fast tmax (298 ± 34·8 min) and those with a fast half-life and fast tmax (249·5 ± 14·4 min) (One-way anovaF = 4·52; P = 0·009). Both rate of absorption and half-life of cortisol in the circulation play important roles in determining overall exposure to oral glucocorticoid. Dose regimens need to incorporate estimates of these parameters into determining the optimum dosing schedule for individuals. © 2014 John Wiley & Sons Ltd.

  18. Sociodemographic Differences by Survey Mode in a Respondent-Driven Sampling Study of Transgender People in Ontario, Canada.

    PubMed

    Scheim, Ayden I; Bauer, Greta R; Coleman, Todd A

    2016-10-01

    To describe survey mode uptake and sociodemographic differences by mode among respondents to a respondent-driven sampling survey of transgender people in Ontario, Canada. Survey mode was left to participant choice. Data were collected from 433 transgender Ontarians in 2009-2010 through a self-administered questionnaire, available online, by paper copy, or by telephone with language interpretation. Paper respondents (9.5%) were significantly more likely to be Aboriginal or persons of color, underhoused, sex workers, and unemployed or receiving disability benefits. In Canada and similar high-income countries, sampling transgender populations that are diverse with respect to social determinants of health may be best carried out with multimode surveys.

  19. Evaluation of the 129I Half-Life Value Through Analyses of Primitive Meteorites

    NASA Astrophysics Data System (ADS)

    Pravdivtseva, Olga; Meshik, Alex; Hohenberg, Charles M.

    The preserved record of decay of now-extinct 129I into 129Xe forms the basis of the I-Xe chronometer. Comparison of the high precision I-Xe and Pb-Pb ages of chondrules and pure mineral phases separated from eight meteorites suggests the 17.5 ÷ 14.6 Ma range for the 129I half-life, assuming that the 235U and 238U half-lives are correct. The mean value of 16 Ma indicates that the 15.7 Ma half-life of 129I used here for the I-Xe age calculations is most probably correct. Since the 129I half-life value only affects the relative I-Xe ages, the few Ma relative to the Shallowater standard, the absolute I-Xe ages are almost immune to this uncertainty in the 129I half-life.

  20. Half-life of Si-32 from tandem-accelerator mass spectrometry

    NASA Technical Reports Server (NTRS)

    Elmore, D.; Anantaraman, N.; Fulbright, H. W.; Gove, H. E.; Nishiizumi, K.; Murrell, M. T.; Honda, M.; Hans, H. S.

    1980-01-01

    A newly developed mass-spectrometry technique employing a tandem Van de Graaff accelerator together with a special beam-transport system and heavy-ion detector has been used to determine the half-life of Si-32. The result obtained, 108 plus or minus 18 yr, disagrees with the accepted value of 330 plus or minus 40 yr. The implications of the new half-life of Si-32, which is used for dating studies, are discussed.