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Sample records for beta strength distribution

  1. On Gamow-Teller strength distributions for $\\beta\\beta$-decaying nuclei within continuum-QRPA

    CERN Document Server

    Igashov, S Yu; Faessler, Amand; Urin, M H

    2010-01-01

    An isospin-selfconsistent pn-continuum-QRPA approach is formulated and applied to describe the Gamow-Teller strength distributions for $\\beta\\beta$-decaying open-shell nuclei. The calculation results obtained for the pairs of nuclei $^{76}$Ge-Se, $^{100}$Mo-Ru, $^{116}$Cd-Sn, and $^{130}$Te-Xe are compared with available experimental data.

  2. Gamow-Teller strength distributions for double-beta-decaying nuclei within continuum-QRPA

    OpenAIRE

    Igashov, S. Yu.; Rodin, V. A.; Urin, M.H.; Faessler, A.

    2007-01-01

    A version of the pn-continuum-QRPA is outlined and applied to describe the Gamow-Teller strength distributions for $\\beta\\beta$-decaying open-shell nuclei. The calculation results obtained for the pairs of nuclei $^{116}$Cd-Sn and $^{130}$Te-Xe are compared with available experimental data.

  3. $\\beta$- decay of $^{58}$Zn. A critical test for the charge-exchange reaction as a probe for the $\\beta$- decay strength distribution

    CERN Multimedia

    2002-01-01

    % IS353 \\\\ \\\\ Due to its importance in fundamental physics and astrophysics, a great effort both theoretically and experimentally is devoted to study Gamow Teller (GT)-strength. The GT-strength and its distribution play a key role in late stellar evolution. During the pre-supernova core-collapse of massive stars, the electron capture and nuclear $\\beta$ -decay determine the electron-to-baryon ratio, which influences the infall dynamics and the mass of the final core. The cross-section of the charge-exchange reaction at forward angles with energies above 100~MeV is expected to be proportional to the squares of Fermi and GT matrix elements. This proportionality should provide a Q-value free method to probe the weak interaction strength and renormalization effects in nuclei. Thus charge-exchange reactions are often used to determine the experimental GT-strength. However, the connection between the GT-strength and the cross-section of the charge-exchange reaction is partially model-dependent and the question aris...

  4. Sizeable beta-strength in 31Ar (beta 3p) decay

    DEFF Research Database (Denmark)

    T. Koldste, G.; Blank, B.; J. G. Borge, M.;

    2014-01-01

    We present for the first time precise spectroscopic information on the recently discovered decay mode beta-delayed 3p-emission. The detection of the 3p events gives an increased sensitivity to the high energy part of the Gamow-Teller strength distribution from the decay of 31Ar revealing that as...... much as 30% of the strength resides in the beta-3p decay mode. A simplified description of how the main decay modes evolve as the excitation energy increases in 31Cl is provided....

  5. Constructions for a bivariate beta distribution

    OpenAIRE

    Olkin, Ingram; Trikalinos, Thomas A.

    2014-01-01

    The beta distribution is a basic distribution serving several purposes. It is used to model data, and also, as a more flexible version of the uniform distribution, it serves as a prior distribution for a binomial probability. The bivariate beta distribution plays a similar role for two probabilities that have a bivariate binomial distribution. We provide a new multivariate distribution with beta marginal distributions, positive probability over the unit square, and correlations over the full ...

  6. Reliability for some bivariate beta distributions

    Directory of Open Access Journals (Sweden)

    Nadarajah Saralees

    2005-01-01

    Full Text Available In the area of stress-strength models there has been a large amount of work as regards estimation of the reliability R=Pr( Xdistributions when X and Y are independent random variables belonging to the same univariate family. In this paper, we consider forms of R when ( X,Y follows a bivariate distribution with dependence between X and Y . In particular, we derive explicit expressions for R when the joint distribution is bivariate beta. The calculations involve the use of special functions.

  7. Parametrizing the exoplanet eccentricity distribution with the Beta distribution

    OpenAIRE

    Kipping, David M.

    2013-01-01

    It is suggested that the distribution of orbital eccentricities for extrasolar planets is well-described by the Beta distribution. Several properties of the Beta distribution make it a powerful tool for this purpose. For example, the Beta distribution can reproduce a diverse range of probability density functions (PDFs) using just two shape parameters (a and b). We argue that this makes it ideal for serving as a parametric model in Bayesian comparative population analysis. The Beta distributi...

  8. The beta strength function structure in \\beta + decay of lutecium, thulium and cesium isotopes

    CERN Document Server

    Alkhazov, G D; Naumov, Yu V; Orlov, S Yu; Vitman, V D

    1981-01-01

    The spectra of total gamma -absorption in the decays of some lutetium, thulium and cesium isotopes have been measured. The probabilities for level population in the decay of the isotopes have been determined. The deduced beta strength functions reveal pronounced structure. Calculations of the strength functions using the Saxon-Woods potential and the residual Gamow-Teller interaction are presented. It is shown that in beta /sup +/ decay of light thulium and cesium isotopes the strength function comprises more than 70% of the Gamow-Teller excitations with mu /sub tau /=+1. This result is the first direct observation of the Gamov-Teller resonance in beta /sup +/ decay of nuclei with T/sub z/>0. (21 refs).

  9. Strength Distribution Analysis of Typical Staple Fibers

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The strength of staple fiber is an important property for yarns and fabrics. Usually there are variations in individual fiber strength, and this will affect the final strength of yarns and fabrics. In this study, Weibull distribution function is used to analyze the strength distribution of various staplefibers. The strengths of wool, silk, cotton, flax, acrylic, polyester, glass, aramid and carbon fiber are tested. It isfound that the strengths of cotton, polyester, glass, aramid and carbon fiber fit well with the two-factor Weibulldistribution, while those of wool and silk with the threefactir Weibull distribution. However, the strength distributionof flax cannot be expressed by either two- or three-factor Weibull distribution convincingly.

  10. High strength beta titanium alloys: New design approach

    International Nuclear Information System (INIS)

    A novel approach for development of high strength and ductile beta titanium alloys was proposed and successfully applied. The microstructure of the designed alloys is fully composed of a bcc β-Ti phase exhibiting dendritic morphology. The new Ti68.8Nb13.6Cr5.1Co6Al6.5 (at%) alloy (BETAtough alloy) exhibits a maximum tensile strength of 1290±50 MPa along with 21±3% of fracture strain. The specific energy absorption value upon mechanical deformation of the BETAtough alloy exceeds that of Ti-based metallic glass composites and commercial high strength Ti-based alloys. The deformation behavior of the new alloys was correlated with their microstructure by means of in-situ studies of the microstructure evolution upon tensile loading in a scanning electron microscope

  11. Dipole strength distributions from HIGS Experiments

    Science.gov (United States)

    Werner, V.; Cooper, N.; Goddard, P. M.; Humby, P.; Ilieva, R. S.; Rusev, G.; Beller, J.; Bernards, C.; Crider, B. P.; Isaak, J.; Kelley, J. H.; Kwan, E.; Löher, B.; Peters, E. E.; Pietralla, N.; Romig, C.; Savran, D.; Scheck, M.; Tonchev, A. P.; Tornow, W.; Yates, S. W.; Zweidinger, M.

    2015-05-01

    A series of photon scattering experiments has been performed on the double-beta decay partners 76Ge and 76Se, in order to investigate their dipole response up to the neutron separation threshold. Gamma-ray beams from bremsstrahlung at the S-DALINAC and from Compton-backscattering at HIGS have been used to measure absolute cross sections and parities of dipole excited states, respectively. The HIGS data allows for indirect measurement of averaged branching ratios, which leads to significant corrections in the observed excitation cross sections. Results are compared to statistical calculations, to test photon strength functions and the Axel-Brink hypothesis

  12. Distribution of crushing strength of tablets

    DEFF Research Database (Denmark)

    Sonnergaard, Jørn

    2002-01-01

    The distribution of a given set of data is important since most parametric statistical tests are based on the assumption that the studied data are normal distributed. In analysis of fracture mechanics the Weibull distribution is widely used and the derived Weibull modulus is interpreted as a mate...... data from nine model tablet formulations and four commercial tablets are shown to follow the normal distribution. The importance of proper cleaning of the crushing strength apparatus is demonstrated. Copyright © 2002 Elsevier Science B.V.......The distribution of a given set of data is important since most parametric statistical tests are based on the assumption that the studied data are normal distributed. In analysis of fracture mechanics the Weibull distribution is widely used and the derived Weibull modulus is interpreted as a...... material constant. However, the estimation of this parameter is laborious and subject to estimation problems. It is shown that the Weibull modulus is inherently connected to the coefficient of variation and that the information obtained from the modulus is unclear. The distribution of crushing strength...

  13. Multipole strength distribution in 112Cd

    International Nuclear Information System (INIS)

    Low-lying excited states of 112Cd have been investigated by means of the inelastic scattering of 30.7 and 60.0 MeV protons with an overall energy resolution of approximately 3x10-4. Most of the known levels, and several others observed for the first time, appear well resolved in final spectra up to about 4 MeV excitation energy. Spin assignments are proposed by comparing measured angular distributions with coupled-channels calculations. A large fragmentation of the hexadecapole strength is found. This is in contrast with the behaviour of the quadrupole and octupole strengths which are mostly concentrated in the first 2+ and 3- levels, respectively. The deduced multipole transition strengths are compared with the predictions of the interacting boson model in the sd, sdf, and sdg boson schemes. (orig.)

  14. Reliability for some bivariate beta distributions

    OpenAIRE

    Nadarajah Saralees

    2005-01-01

    In the area of stress-strength models there has been a large amount of work as regards estimation of the reliability R=Pr( Xdistributions when X and Y are independent random variables belonging to the same univariate family. In this paper, we consider forms of R when ( X,Y ) follows a bivariate distribution with dependence between X and ...

  15. Beta-hypergeometric probability distribution on symmetric matrices

    OpenAIRE

    Hassairi, Abdelhamid; Masmoudi, Mouna

    2012-01-01

    Some remarkable properties of the beta distribution are based on relations involving independence between beta random variables such that a parameter of one among them is the sum of the parameters of an other (see (1.1) et (1.2) below). Asci, Letac and Piccioni \\cite{6} have used the real beta-hypergeometric distribution on $ \\reel$ to give a general version of these properties without the condition on the parameters. In the present paper, we extend the properties of the real beta to the beta...

  16. Free infinite divisibility for beta distributions and related ones

    OpenAIRE

    Hasebe, Takahiro

    2013-01-01

    We prove that many of beta, beta prime, gamma, inverse gamma, Student t- and ultraspherical distributions are freely infinitely divisible, but some of them are not. The latter negative result follows from a local property of probability density functions. Moreover, we show that the Gaussian, many of ultraspherical and Student t-distributions have free divisibility indicator 1.

  17. Free infinite divisibility for beta distributions and related ones

    OpenAIRE

    Hasebe, Takahiro

    2013-01-01

    We prove that many of beta, beta prime, gamma, inverse gamma, Student t- and ultraspherical distributions are freely infinitely divisible, but some of them are not. The latter negative result follows from a local property of probability density functions. Moreover, we show that the Gaussian, ultraspherical and many of Student t-distributions have free divisibility indicator 1.

  18. Library Book Circulation and the Beta-Binomial Distribution.

    Science.gov (United States)

    Gelman, E.; Sichel, H. S.

    1987-01-01

    Argues that library book circulation is a binomial rather than a Poisson process, and that individual book popularities are continuous beta distributions. Three examples demonstrate the superiority of beta over negative binomial distribution, and it is suggested that a bivariate-binomial process would be helpful in predicting future book…

  19. Closed-form expressions for moments of a class of beta generalized distributions

    OpenAIRE

    Cordeiro, Gauss M.; Nadarajah, Saralees

    2011-01-01

    For the first time, we derive explicit closed-form expressions for moments of some beta generalized distributions including the beta gamma, beta normal, beta beta, beta Student t and beta F distributions. These expressions are given as infinite weighted sums of well-known special functions for which numerical routines for computation are available.

  20. Ultra high strength beta titanium alloy for fasteners

    International Nuclear Information System (INIS)

    A new high strength titanium alloy has been developed primarily intended for fastener applications. While Ti-6Al-4V is used extensively as a fastener alloy in the aerospace industry, its shear strength allowable is limited to 655 MPa (95 ksi). For higher shear strength requirements, various steels or nickel-based alloys are used (up to 860 MPa (125 ksi)), but with the attendant density penalty. This new alloy is intended to provide the 860 MPa shear strength at roughly a 40% weight savings. After screening various alloy systems, the optimum chemistry has been selected as follows: Ti-6.0V-6.2Mo-5.7Fe-3Al. In light of its 125 ksi shear strength goal, the alloy has been designated TIMETAL reg-sign 125

  1. Strength distribution in commercial silicon carbide materials

    Science.gov (United States)

    Dutta, Sunil

    1988-01-01

    Four-point flexural strength testing has been conducted in order to establish the baseline strength and reliability of four different commercial SiC types, in conjunction with reliable Weibull modulus values. Average strength of the samples ranged from 380 to 482 MPa at room temperature and 307 to 470 MPa at 1370 C. The strength scatter reflects the effect of flaw variability, which must be minimized to improve reliability in sintered SiC.

  2. Distribution of beta-amyloid in the canine brain.

    Science.gov (United States)

    Hou, Y; White, R G; Bobik, M; Marks, J S; Russell, M J

    1997-03-01

    The distribution of amyloid-beta protein (A beta) in the canine brain was demonstrated by immunochemistry on serially sectioned tissues from 10 aged mixed breed dogs. Summation of quantitative data and relegation to anatomical sites for the 10 dogs showed A beta to be widely distributed in the cortex and hippocampus while completely absent in the brain stem and cerebellum. The highest density of A beta was in the dentate gyrus of the hippocampus. Cortical areas exhibiting the greatest A beta deposition were the posterior and medial suprasylvius gyrus and the proreus gyrus of the frontal lobe. Unlike humans the canine entorhinal cortex, amygdala, basal ganglia and olfactory bulbs were rarely affected. This suggested that the highly developed olfactory pathways of the canine are generally spared from A beta deposition. PMID:9141082

  3. The inverse Lindley distribution: A stress-strength reliability model

    OpenAIRE

    Sharma, Vikas Kumar; Singh, Sanjay Kumar; Singh, Umesh; Agiwal, Varun

    2014-01-01

    In this article, we proposed an inverse Lindley distribution and studied its fundamental properties such as quantiles, mode, stochastic ordering and entropy measure. The proposed distribution is observed to be a heavy-tailed distribution and has a upside-down bathtub shape for its failure rate. Further, we proposed its applicability as a stress-strength reliability model for survival data analysis. The estimation of stress-strength parameters and $R=P[X>Y]$, the stress-strength reliability ha...

  4. A study of the role of Lyman {\\beta} fluorescence on OI line strengths in Be stars

    CERN Document Server

    Mathew, Blesson; Subramaniam, Annapurni; Ashok, N M

    2012-01-01

    The possibility of the Ly{\\beta} fluorescence mechanism being operational in classical Be stars and thereby contributing to the strength of the OI 8446 {\\AA} line has been recognized for long. However this supposition needs to be quantified by comparing observed and predicted OI line ratios. In the present work, optical and near-infrared spectra of classical Be stars are presented. We analyse the observed strengths of the OI 7774, 8446, 11287 and 13165 {\\AA} lines which have been theoretically proposed as diagnostics for identifying the excitation mechanism. We have considered and examined the effects of Ly{\\beta} fluorescence, collisional excitation, recombination and continuum fluorescence on these OI line strengths. From our analysis it appears that the Ly{\\beta} fluorescence process is indeed operative in Be stars.

  5. Estimation of Parameters of the Beta-Extreme Value Distribution

    Directory of Open Access Journals (Sweden)

    Zafar Iqbal

    2008-09-01

    Full Text Available In this research paper The Beta Extreme Value Type (III distribution which is developed by Zafar and Aleem (2007 is considered and parameters are estimated by using moments of the Beta-Extreme Value (Type III Distribution when the parameters ‘m’ & ‘n’ are real and moments of the Beta-Extreme Value (Type III Distribution when the parameters ‘m��� & ‘n’ are integers and then a Comparison between rth moments about origin when parameters are ‘m’ & ‘n’ are real and when parameters are ‘m’ & ‘n’ are integers. At the end second method, method of Maximum Likelihood is used to estimate the unknown parameters of the Beta Extreme Value Type (III distribution.

  6. Resonance structure of strength functions for first-forbidden {beta}{sup +}/EC transitions

    Energy Technology Data Exchange (ETDEWEB)

    Izosimov, I. N., E-mail: izosimov@jinr.ru; Kalinnikov, V. G.; Solnyshkin, A. A. [Joint Institute for Nuclear Research (Russian Federation)

    2012-11-15

    Experimental data obtained by measuring the fine structure of the strength function S{sub {beta}}(E) in spherical and deformed nuclei were analyzed. The use of modern nuclear-spectroscopy methods made it possible to reveal the nuclear-deformation-induced splitting of peaks in S{sub {beta}} (E) for transitions of the Gamow-Teller type. For first-forbidden transitions, the resonance nature of S{sub {beta}} (E) was proven experimentally both for spherical and for deformed nuclei. It is shown that, at some values of the excitation energy, the intensity of first-forbidden transitions in nuclei can be commensurate with the intensity of Gamow-Teller transitions.

  7. Dipole strength distributions from HIGS Experiments

    Directory of Open Access Journals (Sweden)

    Werner V.

    2015-01-01

    76Ge and 76Se, in order to investigate their dipole response up to the neutron separation threshold. Gamma-ray beams from bremsstrahlung at the S-DALINAC and from Compton-backscattering at HIGS have been used to measure absolute cross sections and parities of dipole excited states, respectively. The HIGS data allows for indirect measurement of averaged branching ratios, which leads to significant corrections in the observed excitation cross sections. Results are compared to statistical calculations, to test photon strength functions and the Axel-Brink hypothesis

  8. Beta Distribution of Surface Elevation of Random Waves

    Institute of Scientific and Technical Information of China (English)

    张军; 徐德伦

    2001-01-01

    A probability density function (PDF) is derived of beta distribution with both λ3 (skewness) and λ4 (kurtosis) as parameters for weakly nonlinear wave surface elevation by use of a method recently proposed by Srokosz. This PDF not only has a simpler form than the well-known Gram-Charlier Series PDF derived by Longuet-Higgins, but also overcomes an obvious shortcoming of the latter that when the series is unsuitably truncated, the resulting PDF is locally negative. To test the derived beta PDF, laboratorial experiments of wind waves are conducted. The experimental data indicate that the theoretical requirements of the parameters in the beta PDF are fulfilled. The experimental results show that the present PDF is in better agreement with the measured data than the beta PDF only including parameter λ3, and also than the Gram-Charlier Series PDF truncated up to the term of H6.

  9. Optimum strength distribution for seismic design of tall buildings

    OpenAIRE

    Moghaddam, H.; Hajirasouliha, I.

    2007-01-01

    This paper examines the effects of strength distribution pattern on seismic response of tall buildings. It is shown that in general for an MDOF structure there exists a specific pattern for height-wise distribution of strength and stiffness that results in a better seismic performance in comparison with all other feasible patterns. This paper presents a new optimization technique for optimum seismic design of structures. In this approach, the structural properties are modified so that ineffic...

  10. New method to study the photon strength function using the beta-decay of unstable nuclei

    Science.gov (United States)

    Liddick, Sean

    2015-10-01

    The photon strength function is a fundamental property of the atomic nucleus that can be linked with many different areas of nuclear science. In particular, a knowledge of the photon strength function can be applied in statistical-model reaction calculations to constrain neutron capture rates useful for nuclear astrophysics and other applications. A new method has been developed which takes advantage of beta-decay to populate high-energy states in a daughter nucleus. This preparation is combined with a total absorption spectrometer to record the subsequent gamma-ray cascade and the overall technique is the so-called beta-Oslo method. The technique is applicable to very low production rates (~1 pps) and, thus, can be used to look at trends across a wide range of neutron and proton numbers. A description of the technique, and preliminary results on neutron-rich nuclei near Z = 28 and N = 40 will be presented.

  11. Effect of symmetry breaking on transition strength distributions

    International Nuclear Information System (INIS)

    The quantum numbers of over 100 states in 30P have been determined from the ground state to 8 MeV. Previous measurements had provided complete spectroscopy in 26Al. For these N=Z=odd nuclei, states of isospin T=0 and T=1 coexist at all energies. These spectra provide a unique opportunity to test the effect of symmetry breaking (of the approximate symmetry isospin) on the level statistics and on the transition strength distributions. The level statistics are strongly affected by the small symmetry breaking and the transition strength distributions differ from the Porter-Thomas distribution

  12. The Relationship among the Inspiratory Muscle Strength, the Perception of Dyspnea and Inhaled Beta2-Agonists in Patients with Asthma

    Directory of Open Access Journals (Sweden)

    Paltiel Weiner

    2002-01-01

    Full Text Available BACKGROUND: It is well documented that the perception of dyspnea (POD, subjectively reported by patients, is related to the activity and strength of the inspiratory muscles, and influences the use of 'as needed' beta2-agonists.

  13. How Ionic Strength Affects the Conformational Behavior of Human and Rat Beta Amyloids - A Computational Study

    OpenAIRE

    Kriz Z.; Klusak J.; Kristofikova Z.; Koca J.

    2016-01-01

    Progressive cerebral deposition of amyloid beta occurs in Alzheimeŕs disease and during the aging of certain mammals (human, monkey, dog, bear, cow, cat) but not others (rat, mouse). It is possibly due to different amino acid sequences at positions 5, 10 and 13. To address this issue, we performed series of 100 ns long trajectories (each trajectory was run twice with different initial velocity distribution) on amyloid beta (1–42) with the human and rat amino acid sequence in three different e...

  14. Interleaving distribution of multifractal strength of 16-channel EEG signals

    Institute of Scientific and Technical Information of China (English)

    WANG Wei; NING Xinbao; WANG Jun; ZHANG Sheng; CHEN Jie; LI Lejia

    2003-01-01

    Multifractal characteristics of 16-channel human electroencephalogram (EEG) signals under eye-closed rest are analyzed for the first time. The result shows that the EEGs from the different sites on the scalp have different multifractal characteristics and the multifractal strength value Δα exhibits a kind of interleaving and left-right opposite distribution on scalp. This distribution rule is consistent with the localization of function and the lateralization theory in physiology. SoΔα can become an effective parameter to describe the brain potential character. And such a Δα stable distribution rule on sites of the scalp means a classic cerebral cortex active state.

  15. A COMPOUND OF ZERO TRUNCATED GENERALIZED NEGATIVE BINOMIAL DISTRIBUTION WITH GENERALIZED BETA DISTRIBUTION

    OpenAIRE

    Adil Rashid; Tariq .R. Jan

    2013-01-01

    In this paper, we provide a chronological overview of the recent developments in thecompounding of distributions. An attempt has been made to obtain a compound of zero truncatedgeneralized negative binomial distribution (Ztgnbd) with that of Generalized Beta Distribution(GBD). Factorial and ordinary crude moments of some zero truncated compound distributionshave also been discussed. The compound is then specialized by varying the value of β in((Ztgnbd)).

  16. A COMPOUND OF ZERO TRUNCATED GENERALIZED NEGATIVE BINOMIAL DISTRIBUTION WITH GENERALIZED BETA DISTRIBUTION

    Directory of Open Access Journals (Sweden)

    Adil Rashid

    2013-01-01

    Full Text Available In this paper, we provide a chronological overview of the recent developments in thecompounding of distributions. An attempt has been made to obtain a compound of zero truncatedgeneralized negative binomial distribution (Ztgnbd with that of Generalized Beta Distribution(GBD. Factorial and ordinary crude moments of some zero truncated compound distributionshave also been discussed. The compound is then specialized by varying the value of β in((Ztgnbd.

  17. Certain Family of Some Beta Distributions Arising from Distribution of Randomly Weighted Average

    OpenAIRE

    Roozegar, Rasool

    2015-01-01

    We give the exact distribution of the average of n independent beta random variables weighted by the selected cuts of (0, 1) by the order statistics of a random sample of size n-1 from the uniform distribution U(0,1), for each n. A new integral transformation that is similar to generalized Stieltjes transform is given with various properties. The result of Soltani and Roozegar [On distribution of randomly ordered uniform incremental weighted averages: Divided difference approach. Statist Prob...

  18. Ionic strength independence of charge distributions in solvation of biomolecules

    OpenAIRE

    Virtanen, J. J.; Sosnick, T. R.; Freed, K. F.

    2014-01-01

    Electrostatic forces enormously impact the structure, interactions, and function of biomolecules. We perform all-atom molecular dynamics simulations for 5 proteins and 5 RNAs to determine the dependence on ionic strength of the ion and water charge distributions surrounding the biomolecules, as well as the contributions of ions to the electrostatic free energy of interaction between the biomolecule and the surrounding salt solution (for a total of 40 different biomolecule/solvent combinations...

  19. Sizeable beta-strength in {sup 31}Ar (β3p) decay

    Energy Technology Data Exchange (ETDEWEB)

    Koldste, G.T. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Blank, B. [Centre d' Études Nucléaire de Bordeaux-Gradignan, CNRS/IN2P3 – Université Bordeaux I, F-33175 Gradignan Cedex (France); Borge, M.J.G.; Briz, J.A.; Carmona-Gallardo, M. [Instituto de Estructura de la Materia, CSIC, E-28006 Madrid (Spain); Fraile, L.M. [Grupo de Física Nuclear, Universidad Complutense, CEI Moncloa, E-28040 Madrid (Spain); Fynbo, H.O.U. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Giovinazzo, J. [Centre d' Études Nucléaire de Bordeaux-Gradignan, CNRS/IN2P3 – Université Bordeaux I, F-33175 Gradignan Cedex (France); Johansen, J.G. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Jokinen, A. [Department of Physics, University of Jyväskylä, FIN-40351 Jyväskylä (Finland); Jonson, B. [Fundamental Fysik, Chalmers Tekniska Högskola, S-41296 Göteborg (Sweden); Kurturkian-Nieto, T. [Centre d' Études Nucléaire de Bordeaux-Gradignan, CNRS/IN2P3 – Université Bordeaux I, F-33175 Gradignan Cedex (France); Nilsson, T. [Fundamental Fysik, Chalmers Tekniska Högskola, S-41296 Göteborg (Sweden); Perea, A.; Pesudo, V. [Instituto de Estructura de la Materia, CSIC, E-28006 Madrid (Spain); and others

    2014-10-07

    We present for the first time precise spectroscopic information on the recently discovered decay mode β-delayed 3p-emission. The detection of the 3p events gives an increased sensitivity to the high energy part of the Gamow–Teller strength distribution from the decay of {sup 31}Ar revealing that as much as 30% of the strength resides in the β3p-decay mode. A simplified description of how the main decay modes evolve as the excitation energy increases in {sup 31}Cl is provided.

  20. A Low-Cost Hierarchical Nanostructured Beta-Titanium Alloy with High Strength

    Energy Technology Data Exchange (ETDEWEB)

    Devaraj, Arun; Joshi, Vineet V.; Srivastava, Ankit; Manandhar, Sandeep; Moxson, Vladimir S.; Duz, Volodymr; Lavender, Curt A.

    2016-04-09

    Lightweighting of automobiles by use of novel low-cost, high strength-to-weight ratio structural materials can reduce the consumption of fossil fuels and in turn CO2 emission. Working towards this goal we achieved high strength in a low cost β-titanium alloy, Ti-1Al-8V-5Fe (Ti185), by hierarchical nanostructure consisting of homogenous distribution of micron-scale and nanoscale α-phase precipitates within the β-phase matrix. The sequence of phase transformation leading to this hierarchical nanostructure is explored using electron microscopy and atom probe tomography. Our results suggest that the high number density of nanoscale α-phase precipitates in the β-phase matrix is due to ω assisted nucleation of α resulting in high tensile strength, greater than any current commercial titanium alloy. Thus hierarchical nanostructured Ti185 serves as an excellent candidate for replacing costlier titanium alloys and other structural alloys for cost-effective lightweighting applications.

  1. A low-cost hierarchical nanostructured beta-titanium alloy with high strength

    Science.gov (United States)

    Devaraj, Arun; Joshi, Vineet V.; Srivastava, Ankit; Manandhar, Sandeep; Moxson, Vladimir; Duz, Volodymyr A.; Lavender, Curt

    2016-04-01

    Lightweighting of automobiles by use of novel low-cost, high strength-to-weight ratio structural materials can reduce the consumption of fossil fuels and in turn CO2 emission. Working towards this goal we achieved high strength in a low cost β-titanium alloy, Ti-1Al-8V-5Fe (Ti185), by hierarchical nanostructure consisting of homogenous distribution of micron-scale and nanoscale α-phase precipitates within the β-phase matrix. The sequence of phase transformation leading to this hierarchical nanostructure is explored using electron microscopy and atom probe tomography. Our results suggest that the high number density of nanoscale α-phase precipitates in the β-phase matrix is due to ω assisted nucleation of α resulting in high tensile strength, greater than any current commercial titanium alloy. Thus hierarchical nanostructured Ti185 serves as an excellent candidate for replacing costlier titanium alloys and other structural alloys for cost-effective lightweighting applications.

  2. A Model of the Fatigue Life Distribution of Composite Laminates Based on Their Static Strength Distribution

    Institute of Scientific and Technical Information of China (English)

    Wu Fuqiang; Yao Weixing

    2008-01-01

    The reasons of the static strength dispersion and the fatigue life dispersion of composite laminates are analyzed in this article.It is concluded that the inner original defects,which derived from the manufacturing process of composite laminates,are the common and major reason of causing the random distributions of the static strength and the fatigue life.And there is a correlative relation between the two distributions.With the study of statistical relationship between the fatigue loading and the fatigue life in the uniform confidence level and the same survival rate S-N curves of material,the relationship between the static strength distribution and the fatigue life distribution through a material S-N curve model has been obtained.And then the model which is used to describe the distributions of fatigue life of composites,based on their distributions of static strength,is set up.This model reasonably reflects the effects of the inner original defects on the static strength dispersion and on the fatigue life dispersion of composite laminates.The experimental data of three kinds of composite laminates are employed to verify this model,and the results show that this model can predict the random distributions of fatigue life for composites under any fatigue loads fairly well.

  3. Strength distribution of γ-transitions deexciting superdeformed rotational bands

    International Nuclear Information System (INIS)

    The strength distribution of the γ rays in the decay-out from superdeformed (SD) states is investigated by applying the maximum likelihood method, with special emphasis on the influence of the lower threshold given by experimental conditions. Clear graphical solutions are found, and a careful estimation of the dispersion in the values of the number of degrees of freedom and of the average strength of the most likely χ2 distribution is carried out. For the 194Hg nucleus, 41 primary transitions from the decay-out of SD states are identified above 2600 keV. It is concluded that they represent the strongest 10% of the transitions selected stochastically from a Porter-Thomas distribution. This would support the scenario of a statistical decay of SD states via coupling to a compound state at normal deformation. However, the occurrence of several very strong direct one-step transitions as previously observed in 194Hg has a very small probability of the order of 10-4. This may indicate special selection rules governing the decay. However, based on the absence of strong primary transitions from SD states in adjacent nuclei, the situation in 194Hg is viewed as a very lucky incidence

  4. Spatial distribution of strength and displacement demands for Romanian earthquakes

    International Nuclear Information System (INIS)

    The paper presents part of the results of an extensive study performed on strong earthquakes (moment magnitude larger than 6.0) recorded in Romania in the last 30 years. The study involved the mapping of peak ground motion ordinates as well as of linear and nonlinear spectral ordinates for four seismic events recorded in 1986, 1990 and 2004. A distinct part of the study focused on the mapping and analysis of spectral ordinates for linear and nonlinear acceleration and displacement. Based on the maps, generated for different values of period and ductility, conclusions were drawn on the spatial distribution of strength and displacement demands for the concerned seismic event. (authors)

  5. Bone response and mechanical strength of rabbit femoral defects filled with injectable CaP cements containing TGF-beta 1 loaded gelatin microparticles.

    NARCIS (Netherlands)

    Link, D.P.; Dolder, J. van den; Beucken, J.J.J.P van den; Wolke, J.G.C.; Mikos, A.G.; Jansen, J.A.

    2008-01-01

    This study focused at the potential of transforming growth factor beta 1 (TGF-beta 1) loaded gelatin microparticles to enhance the bone response and mechanical strength of rabbit femoral defects filled with injectable calcium phosphate (CaP)/gelatin microparticle composites. Therefore, TGF-beta1 loa

  6. Ionic strength independence of charge distributions in solvation of biomolecules.

    Science.gov (United States)

    Virtanen, J J; Sosnick, T R; Freed, K F

    2014-12-14

    Electrostatic forces enormously impact the structure, interactions, and function of biomolecules. We perform all-atom molecular dynamics simulations for 5 proteins and 5 RNAs to determine the dependence on ionic strength of the ion and water charge distributions surrounding the biomolecules, as well as the contributions of ions to the electrostatic free energy of interaction between the biomolecule and the surrounding salt solution (for a total of 40 different biomolecule/solvent combinations). Although water provides the dominant contribution to the charge density distribution and to the electrostatic potential even in 1M NaCl solutions, the contributions of water molecules and of ions to the total electrostatic interaction free energy with the solvated biomolecule are comparable. The electrostatic biomolecule/solvent interaction energies and the total charge distribution exhibit a remarkable insensitivity to salt concentrations over a huge range of salt concentrations (20 mM to 1M NaCl). The electrostatic potentials near the biomolecule's surface obtained from the MD simulations differ markedly, as expected, from the potentials predicted by continuum dielectric models, even though the total electrostatic interaction free energies are within 11% of each other. PMID:25494774

  7. A low-cost hierarchical nanostructured beta-titanium alloy with high strength.

    Science.gov (United States)

    Devaraj, Arun; Joshi, Vineet V; Srivastava, Ankit; Manandhar, Sandeep; Moxson, Vladimir; Duz, Volodymyr A; Lavender, Curt

    2016-01-01

    Lightweighting of automobiles by use of novel low-cost, high strength-to-weight ratio structural materials can reduce the consumption of fossil fuels and in turn CO2 emission. Working towards this goal we achieved high strength in a low cost β-titanium alloy, Ti-1Al-8V-5Fe (Ti185), by hierarchical nanostructure consisting of homogenous distribution of micron-scale and nanoscale α-phase precipitates within the β-phase matrix. The sequence of phase transformation leading to this hierarchical nanostructure is explored using electron microscopy and atom probe tomography. Our results suggest that the high number density of nanoscale α-phase precipitates in the β-phase matrix is due to ω assisted nucleation of α resulting in high tensile strength, greater than any current commercial titanium alloy. Thus hierarchical nanostructured Ti185 serves as an excellent candidate for replacing costlier titanium alloys and other structural alloys for cost-effective lightweighting applications. PMID:27034109

  8. Photon strength distributions in stable even-even molybdenum isotopes

    CERN Document Server

    Wagner, A; Erhard, M; Grosse, E; Junghans, A R; Klug, J; Kosev, K; Nair, C; Nankov, N; Rusev, G; Schilling, K D; Schwengner, R

    2007-01-01

    Electromagnetic dipole-strength distributions up to the particle separation energies are studied for the stable even-even nuclides $^{92,94,96,98,100}$Mo in photon scattering experiments at the superconducting electron accelerator ELBE of the Forschungszentrum Dresden-Rossendorf. The influence of inelastic transitions to low-lying excited states has been corrected by a simulation of $\\gamma$ cascades using a statistical model. After corrections for branching ratios of ground-state transitions, the photon-scattering cross-sections smoothly connect to data obtained from $(\\gamma,n)$-reactions. With the newly determined electromagnetic dipole response of nuclei well below the particle separation energies the parametrisation of the isovector giant-dipole resonance is done with improved precision.

  9. Dust Distribution in the beta Pictoris Circumstellar Disks

    CERN Document Server

    Ahmic, Mirza; Artymowicz, Pawel

    2009-01-01

    We present 3-D models of dust distribution around beta Pictoris that produce the best fits to the Hubble Space Telescope Advanced Camera for Surveys' (HST/ACS) images obtained by Golimowski and co-workers. We allow for the presence of either one or two separate axisymmetric dust disks. The density models are analytical, radial two-power-laws joined smoothly at a cross-over radius with density exponentially decreasing away from the mid-plane of the disks. Two-disk models match the data best, yielding a reduced chi^2 of ~1.2. Our two-disk model reproduces many of the asymmetries reported in the literature and suggests that it is the secondary (tilted) disk which is largely responsible for them. Our model suggests that the secondary disk is not constrained to the inner regions of the system (extending out to at least 250 AU) and that it has a slightly larger total area of dust than the primary, as a result of slower fall-off of density with radius and height. This surprising result raises many questions about th...

  10. Investigation of the beta strength function at high energy: Gamma-ray spectroscopy of the decay of 5.3-s 84As to 84Se

    International Nuclear Information System (INIS)

    We have investigated the beta strength function up to approximately 8.6 MeV for the system 84As(β-)84Se. We find that it is not possible to satisfactorily describe Ssub(β) by a statistical model. From the 84As decay scheme we deduce an experimental beta strength function. Additional information on the beta transition intensity is obtained from the gross coincidence spectra of individual gamma rays. In total these data suggest that the experimental beta strength function above 6.8 MeV is significantly lower than that calculated using a statistical model. Features in the gross coincidence spectra also suggest that a significant bump appears in the experimental beta strength function at approximately 6.5 MeV. (orig.)

  11. Determination of the K shell oscillator strengths and the imaginary form factors of atoms using a weak beta source

    Energy Technology Data Exchange (ETDEWEB)

    Hosur, Savita B; Badiger, N M; Naik, L R [Department of Physics, Karnatak University, Dharwad-580 003 (India)], E-mail: nagappa123@yahoo.co.in

    2008-05-14

    The K shell oscillator strengths and the imaginary form factors of Gd, Hf and Ta atoms have been determined using a novel method. In this method, bremsstrahlung photons produced by beta particles from a weak beta source of {sup 90}Sr-{sup 90}Y in a nickel foil are incident on an elemental target and the transmitted spectrum of photons emerging from the target is measured using an ORTEC make HPGe detector coupled to 8 K multichannel analyser. The recorded spectrum shows a sudden drop at the K shell binding energy of the target atom and an exponential decrease in the intensity above the K shell binding energy. These portions have been used to determine the K shell binding energy, photoelectric cross-section at the K edge, the K shell oscillator strength and the imaginary form factor of the elements Gd, Hf and Ta. Good agreement between the experimental and the theoretical values is observed.

  12. Determination of the K shell oscillator strengths and the imaginary form factors of atoms using a weak beta source

    International Nuclear Information System (INIS)

    The K shell oscillator strengths and the imaginary form factors of Gd, Hf and Ta atoms have been determined using a novel method. In this method, bremsstrahlung photons produced by beta particles from a weak beta source of 90Sr-90Y in a nickel foil are incident on an elemental target and the transmitted spectrum of photons emerging from the target is measured using an ORTEC make HPGe detector coupled to 8 K multichannel analyser. The recorded spectrum shows a sudden drop at the K shell binding energy of the target atom and an exponential decrease in the intensity above the K shell binding energy. These portions have been used to determine the K shell binding energy, photoelectric cross-section at the K edge, the K shell oscillator strength and the imaginary form factor of the elements Gd, Hf and Ta. Good agreement between the experimental and the theoretical values is observed

  13. The statistical properties of the angular distribution of beta delayed protons from oriented nuclei

    CERN Document Server

    Stone, N J; Wöhr, A

    2000-01-01

    Statistical model of beta -delayed proton emission is briefly reviewed. Theory of angular distribution of beta -delayed proton emission from nuclear states oriented at low temperatures is discussed and the design of the first trial experiment using /sup 118 /Cs oriented at low temperature at the ISOLDE/NICOLE facility at CERN is described. (14 refs).

  14. Gamow-Teller strength distributions and neutrino energy loss rates due to chromium isotopes in stellar matter

    CERN Document Server

    Nabi, Jameel-Un; Fayaz, Muhammad

    2016-01-01

    Gamow-Teller transitions in isotopes of chromium play a consequential role in the presupernova evolution of massive stars. $\\beta$-decay and electron capture rates on chromium isotopes significantly affect the time rate of change of lepton fraction ($\\dot{Y_{e}}$). Fine-tuning of this parameter is one of the key for simulating a successful supernova explosion. The (anti)neutrinos produced as a result of electron capture and $\\beta$-decay are transparent to stellar matter during presupernova phases. They carry away energy and this result in cooling the stellar core. In this paper we present the calculations of Gamow-Teller strength distributions and (anti)neutrino energy loss rates due to weak interactions on chromium isotopes of astrophysical importance. We compare our results with measured data and previous calculations wherever available.

  15. Newly developed Ti-Nb-Zr-Ta-Si-Fe biomedical beta titanium alloys with increased strength and enhanced biocompatibility.

    Science.gov (United States)

    Kopova, Ivana; Stráský, Josef; Harcuba, Petr; Landa, Michal; Janeček, Miloš; Bačákova, Lucie

    2016-03-01

    Beta titanium alloys are promising materials for load-bearing orthopaedic implants due to their excellent corrosion resistance and biocompatibility, low elastic modulus and moderate strength. Metastable beta-Ti alloys can be hardened via precipitation of the alpha phase; however, this has an adverse effect on the elastic modulus. Small amounts of Fe (0-2 wt.%) and Si (0-1 wt.%) were added to Ti-35Nb-7Zr-6Ta (TNZT) biocompatible alloy to increase its strength in beta solution treated condition. Fe and Si additions were shown to cause a significant increase in tensile strength and also in the elastic modulus (from 65 GPa to 85 GPa). However, the elastic modulus of TNZT alloy with Fe and Si additions is still much lower than that of widely used Ti-6Al-4V alloy (115 GPa), and thus closer to that of the bone (10-30 GPa). Si decreases the elongation to failure, whereas Fe increases the uniform elongation thanks to increased work hardening. Primary human osteoblasts cultivated for 21 days on TNZT with 0.5Si+2Fe (wt.%) reached a significantly higher cell population density and significantly higher collagen I production than cells cultured on the standard Ti-6Al-4V alloy. In conclusion, the Ti-35Nb-7Zr-6Ta-2Fe-0.5Si alloy proves to be the best combination of elastic modulus, strength and also biological properties, which makes it a viable candidate for use in load-bearing implants. PMID:26706526

  16. Uniform Asymptotic Normality of the Matrix-variate Beta-distribution

    Institute of Scientific and Technical Information of China (English)

    Kai Can LI; He TANG

    2012-01-01

    With the upper bound of Kullback-Leibler distance between a matrix variate Beta-distribution and a normal distribution,this paper gives the conditions under which a matrix-variate Betadistribution will approach uniformly and asymptotically a normal distribution.

  17. On k-Gamma and k-Beta Distributions and Moment Generating Functions

    Directory of Open Access Journals (Sweden)

    Gauhar Rahman

    2014-01-01

    Full Text Available The main objective of the present paper is to define k-gamma and k-beta distributions and moments generating function for the said distributions in terms of a new parameter k>0. Also, the authors prove some properties of these newly defined distributions.

  18. The pharmacokinetics, distribution and degradation of human recombinant interleukin 1 beta in normal rats

    DEFF Research Database (Denmark)

    Reimers, J; Wogensen, L D; Welinder, B;

    1991-01-01

    distribution (T1/2 alpha) and elimination phases (T1/2 beta) of human recombinant interleukin 1 beta (rIL-1 beta), and its tissue distribution and cellular localization by means of mono-labelled, biologically active 125I-rIL-1 beta. After intravenous (i.v.) injection, 125I-rIL-1 beta was eliminated from the......Based upon in vivo rat experiments it was recently suggested that interleukin 1 in the circulation may be implicated in the initial events of beta-cell destruction leading to insulin-dependent diabetes mellitus (IDDM) in humans. The aim of the present study was to estimate half-lives of...... circulation with a T1/2 alpha of 2.9 min and a T1/2 beta of 41.1 min. The central and peripheral volume of distribution was 20.7 and 19.1 ml/rat, respectively, and the metabolic clearance rate was 16.9 ml/min/kg. The kidney and liver showed the highest accumulation of tracer, and autoradiography demonstrated...

  19. The statistical distribution of magnetic field strength in G-band bright points

    CERN Document Server

    Criscuoli, Serena

    2013-01-01

    G-band bright points are small-sized features characterized by high photometric contrast. Theoretical investigations indicate that these features have associated magnetic field strengths between 1-2 kG. Results from observations instead lead to contradictory results, indicating magnetic fields of only kG strength in some and including hG strengths in others. In order to understand the differences between measurements reported in the literature, and to reconcile them with results from theory, we analyze the distribution of magnetic field strength of G-band bright features identified on synthetic images of the solar photosphere, and its sensitivity to observational and methodological effects. We investigate the dependence of magnetic field strength distributions of G-band bright points identified in 3D magnetohydrodynamic simulations on feature selection method, data sampling, alignment and spatial resolution. The distribution of magnetic field strength of G-band bright features shows two peaks, one at about 1....

  20. On the increasing of adhesive strength of nanotube layers on beta titanium alloys for medical applications

    Science.gov (United States)

    Fojt, Jaroslav; Filip, Vladimir; Joska, Ludek

    2015-11-01

    The nanostructuring of titanium and its alloys surfaces is used inter alia for increasing the medical implants osseointegration. Many papers about this topic were published. However, in most cases there were no informations about nanostructures adhesion to the surface, which is crucial from the application point of view. The aim of this study was to prepare nanostructures on titanium beta alloy and optimized its adhesion to the alloy surface. Nanotubes were formed by anodic polarization in electrolyte containing fluoride ions. The composition of the nanotubes was described by X-ray photoelectron spectroscopy. Nanostructures adhesion was tested by pull-of method. The nanotubes on the Ti-36Nb-6Ta beta alloy surface were prepared by anodization. The nanostructures properties were modified by electrochemical process parameters. The adhesion of the nanotubes prepared in this work was satisfactory for implantological applications.

  1. Chromosome aberration analysis based on a beta-binomial distribution

    International Nuclear Information System (INIS)

    Analyses carried out here generalized on earlier studies of chromosomal aberrations in the populations of Hiroshima and Nagasaki, by allowing extra-binomial variation in aberrant cell counts corresponding to within-subject correlations in cell aberrations. Strong within-subject correlations were detected with corresponding standard errors for the average number of aberrant cells that were often substantially larger than was previously assumed. The extra-binomial variation is accomodated in the analysis in the present report, as described in the section on dose-response models, by using a beta-binomial (B-B) variance structure. It is emphasized that we have generally satisfactory agreement between the observed and the B-B fitted frequencies by city-dose category. The chromosomal aberration data considered here are not extensive enough to allow a precise discrimination between competing dose-response models. A quadratic gamma ray and linear neutron model, however, most closely fits the chromosome data. (author)

  2. The effects of 12 weeks of beta-hydroxy-beta-methylbutyrate free acid supplementation on muscle mass, strength, and power in resistance-trained individuals: a randomized, double-blind, placebo-controlled study

    OpenAIRE

    Wilson, Jacob M.; Lowery, Ryan P; Joy, Jordan M; Andersen, J.C.; Wilson, Stephanie M. C.; Stout, Jeffrey R; Duncan, Nevine; Fuller, John C; Baier, Shawn M; Naimo, Marshall A.; Rathmacher, John

    2014-01-01

    Introduction Studies utilizing beta-hydroxy-beta-methylbutyrate (HMB) supplementation in trained populations are limited. No long-term studies utilizing HMB free acid (HMB-FA) have been conducted. Therefore, we investigated the effects of 12 weeks of HMB-FA supplementation on skeletal muscle hypertrophy, body composition, strength, and power in trained individuals. We also determined the effects of HMB-FA on muscle damage and performance during an overreaching cycle. Methods A three-phase dou...

  3. The prediction of fatigue strength for teeth root in gear mechanism by weibull distribution

    International Nuclear Information System (INIS)

    The prediction of fatigue strength for teeth root in gear mechanism, so far, has been calculated by normal distribution with 50% reliability consideration. In this study, the results of teeth root break in evaluated in more realistic sense based on Weibull distribution approach in the region of finite life. By this approach the so called fatigue strength diagrams were obtained with specified reliability level. (author)

  4. ESTIMATION OF RELIABILITY FOR MULTICOMPONENT SYSTEMS USING EXPONENTIAL, GAMMA AND LINDLEY STRESS-STRENGTH DISTRIBUTIONS

    Directory of Open Access Journals (Sweden)

    J. Gogoi

    2012-01-01

    Full Text Available This paper deals with the stress vs. strength problem incorporating multi-componentsystems viz. standby redundancy. The models developed have been illustrated assuming that allthe components in the system for both stress and strength are independent and follow differentprobability distributions viz. Exponential, Gamma and Lindley. Four different conditions forstress and strength have been considered for this investigation. Under these assumptions thereliabilities of the system have been obtained with the help of the particular forms of densityfunctions of n-standby system when all stress-strengths are random variables. The expressions forthe marginal reliabilities R(1, R(2, R(3 etc. have been derived based on its stress- strengthmodels. Then the corresponding system reliabilities Rn have been computed numerically andpresented in tabular forms for different stress-strength distributions with different values of theirparameters. Here we consider n  3 for estimating the system reliability R3.

  5. Spectral distribution Method for neutrinoless double beta decay: Results for $^{82}$Se and $^{76}$Ge

    CERN Document Server

    Kota, V K B

    2016-01-01

    Statistical spectral distribution method based on shell model and random matrix theory is developed for calculating neutrinoless double beta decay nuclear transition matrix elements. First results obtained for $^{82}$Se and $^{76}$Ge using the spectral method are close to the available shell model results.

  6. Directional distributions of beta-rays emitted from oriented nuclei

    International Nuclear Information System (INIS)

    A unique ultralow-temperature nuclear orientation facility was developed with which the directional distributions of β-rays emitted from statically polarized nuclei can be observed, for the first time, at many angles with respect to the polarization axis. Nuclei can be polarized in bulk by imbedding them in an appropriate ferromagnetic host, which is cooled to near absolute zero temperature and is magnetized to saturation with an externally applied field. The polarization axis is defined by the direction of this applied field. The two distinguishing features of the new system are the following: the necessary temperature of about 0.010K can be maintained very accurately for as long as is necessary by a 3He/4He dilution refrigerator; and the polarization axis can be rotated, while the source and the detector are kept stationary, by varying the external fields applied by intersecting magnetic loops. These loops leak a negligible amount of magnetic flux into the region traversed by the β rays, and thus leave β-ray trajectories essentially unaltered. In the first experiment performed on the facility, the angular dependence of the parity-violating term in the directional distribution function for β rays emitted from polarized 60Co nuclei was directly measured for the first time. The results were found to be consistent with the accepted theories of nuclear β decay. Additional fundamental experiments possible with this new facility involving parity violation, isospin nonconservation, and time-reversal invariance are discussed

  7. Molecular mass distribution and epitopes of the beta lactoglobulin submitted to hydrolysis pre-transglutaminase treatment

    Energy Technology Data Exchange (ETDEWEB)

    Villas-Boas, M.B.; Zollner, R.L.; Netto, F.M. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil); Paes Leme, A.F. [Laboratorio Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Benede, S.; Molina, E. [Universidad Autonoma de Madrid (Spain)

    2012-07-01

    Full text: The {beta}-Lactoglobulin ({beta}-Lg) is a whey protein with important nutritional proper ties but very resistant to pepsin digestion and consequently highly antigenic. This protein can be modified by transglutaminase (TG) although it is required a pretreatment to increase their susceptibility to the TG action. In the present study the hydrolysis pre-TG treatment was used to improve the TG accessibility on {beta}-Lg and the MM distribution and antigenic fragments were evaluated. For pre-TG treatment, the {beta}-Lg (Davisco Inc.) was hydrolyzed with bromelain (3% of {beta}-Lg w/w in distilled water; 25 U enzyme g{sup 1} of substrate, pH 7.5, 240 min) and then polymerized by TG (7% hydrolysate, 10U TG g{sup 1} protein, 50 C/180 min). The samples were evaluated by SDS-PAGE/tricine and by RP-nanoUPLC (nanoAcquity UPLC, Waters) coupled with nano-electrospray tandem mass spectrometry on a Q-Tof Ultima API mass spectrometer (MicroMass/Waters) at LNBio. The products were also submitted to pepsin digestion and the peptide identification was performed by RP-HPLC-tandem mass spectrometry (RP-HPLC-MS/MS, Brucker) with support from CIAL. The {beta}-Lg hydrolysed by bromelain and polymerized by TG had a broad MM distribution. The intact mass analysis indicated that the non modified {beta}Lg -A showed 18.362 Da and the non modified {beta}Lg -B 18.274 Da, which is in agreement with the theoretical corresponding masses. The use of bromelain pre-TG treatment resulted in polymers with MM from 61.052 to 67.654 Da, although some non modified protein was still present. In addition, the non modified {beta}-Lg showed fragments that present high antigenicity (such as Leu{sub 95} - Leu{sub 104}, Asp{sub 95} - Phe{sub 105}, Tyr{sub 42} - Leu{sub 54}, lle{sub 29} - Val{sub 41}), previously identified as IgE-binding epitopes. After hydrolysis following by TG treatment the fragment Tyr{sub 42} - Leu{sub 54} was still present, however the other fragments that were observed in the non

  8. THE STRENGTH OF THE DISSOLVED OXYGEN MAXIMUM IN THE VERTICAL DISTRIBUTION OF NANSHA ISLANDS WATERS

    Institute of Scientific and Technical Information of China (English)

    林洪瑛; 程赛伟; 韩舞鹰

    2002-01-01

    Observation data from a cruise in the Nansha Islands, in May to June 1990, December, 1993, September to October 1994, and July, 1999, respectively, were used to develop the method presented here to indicate the existing strength of the dissolved oxygen maximum in the vertical distribution of Nansha Islands waters. Its seasonal variation and regional distribution are discussed in this paper. Analysis results showed that the distribution of the strength of dissolved oxygen maximum (DOmax-DOsur) was closely related to the upper layer circulation and the bioactivity of Nansha Islands seawater.

  9. THE STRENGTH OF THE DISSOLVED OXYGEN MAXIMUM IN THE VERTICAL DISTRIBUTION OF N ANSHA ISLANDS WATERS

    Institute of Scientific and Technical Information of China (English)

    林洪瑛; 程赛伟; 韩舞鹰

    2002-01-01

    Observation data from a cruise in the Nansha Islands, in May to June 1990, Decem ber, 1993, September to October 1994, and July, 1999, respectively, were used to develop the method presented here to indicate the existing strength of the diss ol ved oxygen maximum in the vertical distribution of Nansha Islands waters. Its se asonal variation and regional distribution are discussed in this paper. Analysis results showed that the distribution of the strength of dissolved oxygen maximum (Domax-Dosur) was closely related to the upper layer circulation and the bioactivity of Nansha Islands seawater.

  10. Tail universalities in rank distributions as an algebraic problem: the beta-like function

    CERN Document Server

    Naumis, Gerardo G

    2007-01-01

    Although power laws of the Zipf type have been used by many workers to fit rank distributions in different fields like in economy, geophysics, genetics, soft-matter, networks etc., these fits usually fail at the tails. Some distributions have been proposed to solve the problem, but unfortunately they do not fit at the same time both ending tails. We show that many different data in rank laws, like in granular materials, codons, author impact in scientific journal, etc. are very well fitted by a beta-like function. Then we propose that such universality is due to the fact that a system made from many subsystems or choices, imply stretched exponential frequency-rank functions which qualitatively and quantitatively can be fitted with the proposed beta-like function distribution in the limit of many random variables. We prove this by transforming the problem into an algebraic one: finding the rank of successive products of a given set of numbers.

  11. Developments for a measurement of the beta -- nu correlation and determination of the recoil charge-state distribution in 6He beta decay

    Science.gov (United States)

    Hong, Ran

    The beta-nu of a pure Gamow-Teller beta decay such as the 6He decay is sensitive to tensor-type weak currents predicted by theories beyond the Standard Model. An experiment is developed at University of Washington aiming at measuring the coefficient a_{beta-nu} of 6He decays to the 0.1% level and looking for its deviation from the Standard-Model prediction -1/3 using laser-trapped 6He atoms. The beta particle is detected by a scintillator and a multi-wire proportional chamber, and the recoil ion is detected by a microchannel plate with delay-line anodes for position readouts. a_{beta-nu} is extracted by fitting the measured time-of-flight spectrum of the recoil ions to templates generated by Monte Carlo simulations. This dissertation describes the developments of this experiment for the intermediate goal of a 1% level a_{beta-nu} measurement, such as the detector design, Monte Carlo simulation software, and data analysis frame work. Particularly, detector calibrations are described in detail. The analysis of a 2% level proof-of-principle run in October 2015 is presented as well. Shake-off probabilities for decays of trapped 6He atoms matter for the high-precision a_{beta-nu} measurement. The charge state distribution of recoil ions is obtained by analyzing their time-of-flight distribution using the same experimental setups for the a_{beta-nu} measurement. An analysis approach that is independent of the beta-nu correlation is developed. The measured upper limit of the double shake-off probability is 2x10. {-4} at 90% confidence level. This result is 100 times lower than the most recent calculation by Schulhoff and Drake. This disagreement is significant for the a_{beta-nu} measurement and needs to be addressed by improved atomic theory calculations.

  12. Beta decay of 31Ar

    International Nuclear Information System (INIS)

    A complete study of 31Ar beta decay has been made by high-resolution charged-particle and gamma-ray spectroscopy. Beta-delayed radiation was detected by an array of three charged-particle detectors and a large-volume germanium detector. Fifteen new energy levels were discovered in 31Cl. The beta-strength distribution, measured to 14.5 MeV, is compared with a shell-model calculation in the full sd space. The quenching of the Gamow-Teller strength and the isospin impurity of the IAS in 31Cl are discussed. (orig.)

  13. Size effect on strength and lifetime probability distributions of quasibrittle structures

    Indian Academy of Sciences (India)

    Zdeněk P Bažant; Jia-Liang Le

    2012-02-01

    Engineering structures such as aircraft, bridges, dams, nuclear containments and ships, as well as computer circuits, chips and MEMS, should be designed for failure probability < $10^{-6}-10^{-7}$ per lifetime. The safety factors required to ensure it are still determined empirically, even though they represent much larger and much more uncertain corrections to deterministic calculations than do the typical errors of modern computer analysis of structures. The empirical approach is sufficient for perfectly brittle and perfectly ductile structures since the cumulative distribution function (cdf) of random strength is known, making it possible to extrapolate to the tail from the mean and variance. However, the empirical approach does not apply to structures consisting of quasibrittle materials, which are brittle materials with inhomogeneities that are not negligible compared to structure size. This paper presents a refined theory on the strength distribution of quasibrittle structures, which is based on the fracture mechanics of nanocracks propagating by activation energy controlled small jumps through the atomic lattice and an analytical model for the multi-scale transition of strength statistics. Based on the power law for creep crack growth rate and the cdf of material strength, the lifetime distribution of quasibrittle structures under constant load is derived. Both the strength and lifetime cdfs are shown to be sizeand geometry-dependent. The theory predicts intricate size effects on both the mean structural strength and lifetime, the latter being much stronger. The theory is shown to match the experimentally observed systematic deviations of strength and lifetime histograms of industrial ceramics from the Weibull distribution.

  14. Recoil ion charge state distribution following the beta(sup +) decay of {sup 21}Na

    Energy Technology Data Exchange (ETDEWEB)

    Scielzo, Nicholas D.; Freedman, Stuart J.; Fujikawa, Brian K.; Vetter, Paul A.

    2003-01-03

    The charge state distribution following the positron decay of 21Na has been measured, with a larger than expected fraction of the daughter 21Ne in positive charge states. No dependence on either the positron or recoil nucleus energy is observed. The data is compared to a simple model based on the sudden approximation. Calculations suggest a small but important contribution from recoil ionization has important consequences for precision beta decay correlation experiments detecting recoil ions.

  15. Recoil ion charge state distribution following the beta(sup +) decay of 21Na

    International Nuclear Information System (INIS)

    The charge state distribution following the positron decay of 21Na has been measured, with a larger than expected fraction of the daughter 21Ne in positive charge states. No dependence on either the positron or recoil nucleus energy is observed. The data is compared to a simple model based on the sudden approximation. Calculations suggest a small but important contribution from recoil ionization has important consequences for precision beta decay correlation experiments detecting recoil ions

  16. A joint finite mixture model for clustering genes from independent Gaussian and beta distributed data

    Directory of Open Access Journals (Sweden)

    Yli-Harja Olli

    2009-05-01

    Full Text Available Abstract Background Cluster analysis has become a standard computational method for gene function discovery as well as for more general explanatory data analysis. A number of different approaches have been proposed for that purpose, out of which different mixture models provide a principled probabilistic framework. Cluster analysis is increasingly often supplemented with multiple data sources nowadays, and these heterogeneous information sources should be made as efficient use of as possible. Results This paper presents a novel Beta-Gaussian mixture model (BGMM for clustering genes based on Gaussian distributed and beta distributed data. The proposed BGMM can be viewed as a natural extension of the beta mixture model (BMM and the Gaussian mixture model (GMM. The proposed BGMM method differs from other mixture model based methods in its integration of two different data types into a single and unified probabilistic modeling framework, which provides a more efficient use of multiple data sources than methods that analyze different data sources separately. Moreover, BGMM provides an exceedingly flexible modeling framework since many data sources can be modeled as Gaussian or beta distributed random variables, and it can also be extended to integrate data that have other parametric distributions as well, which adds even more flexibility to this model-based clustering framework. We developed three types of estimation algorithms for BGMM, the standard expectation maximization (EM algorithm, an approximated EM and a hybrid EM, and propose to tackle the model selection problem by well-known model selection criteria, for which we test the Akaike information criterion (AIC, a modified AIC (AIC3, the Bayesian information criterion (BIC, and the integrated classification likelihood-BIC (ICL-BIC. Conclusion Performance tests with simulated data show that combining two different data sources into a single mixture joint model greatly improves the clustering

  17. The effects of 10 weeks of resistance training combined with beta-alanine supplementation on whole body strength, force production, muscular endurance and body composition.

    Science.gov (United States)

    Kendrick, Iain P; Harris, Roger C; Kim, Hyo Jeong; Kim, Chang Keun; Dang, Viet H; Lam, Thanh Q; Bui, Toai T; Smith, Marcus; Wise, John A

    2008-05-01

    Carnosine (Carn) occurs in high concentrations in skeletal muscle is a potent physico-chemical buffer of H+ over the physiological range. Recent research has demonstrated that 6.4 g x day(-1) of beta-alanine (beta-ala) can significantly increase skeletal muscle Carn concentrations (M-[Carn]) whilst the resultant change in buffering capacity has been shown to be paralleled by significant improvements in anaerobic and aerobic measures of exercise performance. Muscle carnosine increase has also been linked to increased work done during resistance training. Prior research has suggested that strength training may also increase M-[Carn] although this is disputed by other studies. The aim of this investigation is to assess the effect of 10 weeks resistance training on M-[Carn], and, secondly, to investigate if increased M-[Carn] brought about through beta-ala supplementation had a positive effect on training responses. Twenty-six Vietnamese sports science students completed the study. The subjects completed a 10-week resistance-training program whilst consuming 6.4 g x day(-1) of beta-ala (beta-ALG) or a matched dose of a placebo (PLG). Subjects were assessed prior to and after training for whole body strength, isokinetic force production, muscular endurance, body composition. beta-Alanine supplemented subjects increased M-[Carn] by 12.81 +/- 7.97 mmol x kg(-1) dry muscle whilst there was no change in PLG subjects. There was no significant effect of beta-ala supplementation on any of the exercise parameters measured, mass or % body fat. In conclusion, 10 weeks of resistance training alone did not change M-[Carn]. PMID:18175046

  18. Effects of Horizontal Density Distribution on Internal Bond Strength of Flakeboard

    Institute of Scientific and Technical Information of China (English)

    MEIChangtong; DAIChunping; ZHOUDingguo

    2005-01-01

    Horizontal density variation is a structural phenomenon of non-veneer wood composites. The variation and distribution characteristics of horizontal density have impacts on the products properties. In this study, veneer strip simulated flake boards with 4 kinds of density distribution were made using a mat model. The density variation of the modeled mats was discussed, as well as the relationship between sample size and density variation. The effects of density and density distribution of non-veneer composites on the internal bond strength were analyzed. Result shows that the horizontal density of random formed particleboard follows normal distribution. Density has remarkable influence on internal bond strength (IB). Increasing density helps to improve IB at lower density stage, but has negative impacts on IB at higher density stage.Density variation between testing specimens depends on their sizes. Properly increasing specimen size can decrease the variation of the IBs.

  19. The pharmacokinetics, distribution and degradation of human recombinant interleukin 1 beta in normal rats

    DEFF Research Database (Denmark)

    Wogensen, L D; Welinder, B; Hejnaes, K R;

    1991-01-01

    circulation with a T1/2 alpha of 2.9 min and a T1/2 beta of 41.1 min. The central and peripheral volume of distribution was 20.7 and 19.1 ml/rat, respectively, and the metabolic clearance rate was 16.9 ml/min/kg. The kidney and liver showed the highest accumulation of tracer, and autoradiography demonstrated...... that 125I-rIL-1 beta was localized to the proximal tubules in the kidney and to the hepatocytes in the liver. Furthermore, grains were localized to the islets of Langerhans in the pancreas. Tracer-bound proteins corresponding to intact 125I-rIL-1 beta were found in the circulation after i.......v., intraperitoneal (i.p.) and subcutaneous (s.c.) injections, as demonstrated by high performance size exclusion chromatography, trichloracetic acid precipitation and SDS-PAGE until 5 h after tracer injection. Pre-treatment with 'cold' rIL-1 beta enhanced degradation of a subsequent injection of tracer. The route of...

  20. Carbon fiber/carbon nanotube reinforced hierarchical composites: Effect of CNT distribution on shearing strength

    DEFF Research Database (Denmark)

    Zhou, H. W.; Mishnaevsky, Leon; Yi, H. Y.;

    2016-01-01

    The strength and fracture behavior of carbon fiber reinforced polymer composites with carbon nanotube (CNT) secondary reinforcement are investigated experimentally and numerically. Short Beam Shearing tests have been carried out, with SEM observations of the damage evolution in the composites. 3D...... multiscale computational (FE) models of the carbon/polymer composite with varied CNT distributions have been developed and employed to study the effect of the secondary CNT reinforcement, its distribution and content on the strength and fracture behavior of the composites. It is shown that adding secondary...... CNT nanoreinforcement into the matrix and/or the sizing of carbon fiber/reinforced composites ensures strong increase of the composite strength. The effect of secondary CNTs reinforcement is strongest when some small addition of CNTs in the polymer matrix is complemented by the fiber sizing with high...

  1. A simple model for the distribution of quiet Sun magnetic field strengths

    CERN Document Server

    Almeida, J S

    2006-01-01

    We derive a first order linear differential equation describing the shape of the probability density function of magnetic field strengths in the quiet Sun (PDF). The modeling is very schematic. It considers convective motions which continuously supply and withdraw magnetic structures. In addition, a magnetic amplification mechanism increases the field strength up to a threshold that cannot be exceeded. These three basic ingredients provide PDFs in good agreement with the PDFs produced by realistic numerical simulations of magneto convection, as well as with quiet Sun PDFs inferred from observations. In particular, the distribution is approximately lognormal, and it produces an excess of magnetic fields (i.e., a 'hump' in the distribution) right before the maximum field strength. The success of this simple model may indicate that only a few basic ingredients shape the quiet Sun PDF. Our approach provides a concise parametric representation of the PDF, as required to develop automatic methods of diagnostics.

  2. News on $\\beta$-delayed particle emission from $^{14}$Be

    CERN Document Server

    Jeppesen, H; Borge, M J G; Cederkäll, J; Fynbo, H O U; Fedoseyev, V N; Hansper, V Y; Jonson, B; Markenroth, K; Mishin, V I; Nilsson, T; Nyman, G; Riisager, K; Tengblad, O; Wilhelmsen Rolander, K

    2002-01-01

    $\\beta$-delayed charged particles from $^{14}$Be have been measured and give an upper limit on $\\beta$-delayed $\\alpha$-particles of B($\\beta\\alpha$) < $\\,6.7\\times\\!10^{-5}$ and a tentative branching ratio on $\\beta$-delayed tritons of $7.5\\times\\!10^{-5}$ < B($\\beta$t) < $\\,3.9\\times\\!10^{-4}$. We combine the knowledge on $\\beta$-delayed particles from $^{14}$Be to deduce information on the $\\beta$-strength distribution.

  3. Online learning of a Dirichlet process mixture of Beta-Liouville distributions via variational inference.

    Science.gov (United States)

    Fan, Wentao; Bouguila, Nizar

    2013-11-01

    A large class of problems can be formulated in terms of the clustering process. Mixture models are an increasingly important tool in statistical pattern recognition and for analyzing and clustering complex data. Two challenging aspects that should be addressed when considering mixture models are how to choose between a set of plausible models and how to estimate the model's parameters. In this paper, we address both problems simultaneously within a unified online nonparametric Bayesian framework that we develop to learn a Dirichlet process mixture of Beta-Liouville distributions (i.e., an infinite Beta-Liouville mixture model). The proposed infinite model is used for the online modeling and clustering of proportional data for which the Beta-Liouville mixture has been shown to be effective. We propose a principled approach for approximating the intractable model's posterior distribution by a tractable one-which we develop-such that all the involved mixture's parameters can be estimated simultaneously and effectively in a closed form. This is done through variational inference that enjoys important advantages, such as handling of unobserved attributes and preventing under or overfitting; we explain that in detail. The effectiveness of the proposed work is evaluated on three challenging real applications, namely facial expression recognition, behavior modeling and recognition, and dynamic textures clustering. PMID:24808617

  4. Distribution of estrogens, 17{beta}-estradiol and estrone, in Canadian municipal wastewater treatment plants

    Energy Technology Data Exchange (ETDEWEB)

    Servos, M.R.; Bennie, D.T.; Burnison, B.K.; Jurkovic, A.; McInnis, R.; Neheli, T.; Schnell, A.; Seto, P.; Smyth, S.A.; Ternes, T.A

    2005-01-05

    The distribution of female hormones, 17{beta}-estradiol and estrone, was determined in effluents of 18 selected municipal treatment plants across Canada. Replicate 24-h composite samples were collected from the influent and final effluent of each treatment plant, and the removal efficiency compared to the operational characteristics of the plants. In conventional activated sludge and lagoon treatment systems, the mean concentrations of 17{beta}-estradiol and estrone in influent were 15.6 ng/l (range 2.4-26 ng/l) and 49 ng/l (19-78 ng/l). In final effluents, the mean concentrations of both 17{beta}-estradiol and estrone were reduced to 1.8 ng/l (0.2-14.7 ng/l) and 17 ng/l (1-96 ng/l), respectively. 17{beta}-estradiol was removed effectively, >75% and as high as 98%, in most of the conventional mechanical treatment systems with secondary treatment. The removal of estrone was much more complex with removal varying from 98% to situations where the concentrations in the effluent were elevated above that detected in the influent. The estrogenicity, measured using a transfected estrogen receptor in yeast (YES) assay, was also variable, ranging from high removal to elevations of estrogenicity in final effluent. Although the apparent removals were not statistically correlated with either hydraulic (HRT) or solid (SRT) retention times, plants or lagoons with high SRT were very effective at reducing the levels of hormones. Well-operated plants that achieved nitrification also tended to have higher removal of hormones than those that did not nitrify. Laboratory aerobic reactor experiments confirmed the rapid removal of 17{beta}-estradiol, estrone, and estrogenicity when exposed to sewage slurries.

  5. The progression and topographic distribution of interleukin-1beta expression after permanent middle cerebral artery occlusion in the rat.

    Science.gov (United States)

    Davies, C A; Loddick, S A; Toulmond, S; Stroemer, R P; Hunt, J; Rothwell, N J

    1999-01-01

    The cytokine interleukin-1 (IL-1) has been implicated in the exacerbation of ischemic damage in the brains of rodents. This study has ascertained the cellular localization and chronologic and topographic distribution of pro/mature interleukin-1beta (IL-1beta) protein 0.5, 1, 2, 6, 24, and 48 hours after ischemia by subjecting rats to permanent unilateral occlusion of the middle cerebral artery. Interleukin-1beta was localized immunocytochemically in vibratome sections of perfusion-fixed brains. The cells that expressed IL-1beta had the morphologic features of microglia and macrophages. Interleukin-1beta was first detected 1 hour after occlusion in ipsilateral meningeal macrophage-like cells. By 6 hours, pro/mature IL-1beta-immunoreactive (IL-1(beta)ir) putative microglia were present in the ischemic cerebral cortex, corpus callosum, caudoputamen, and surrounding tissue. By 24 and 48 hours after ischemia, the number and spread of IL-1(beta)ir cells increased greatly, including those resembling activated microglia and macrophages, as the core of the infarct became infiltrated. Interleukin-1(beta)ir cells also were present in apparently undamaged tissue, adjacent to the lesion ipsilaterally, and contralaterally in the cerebral cortex, dorsal corpus callosum, dorsal caudoputamen, and hippocampus. These results support the functional role of IL-1 in ischemic brain damage and reveal a distinct temporal and spatial expression of IL-1beta protein in cells believed to be microglia and macrophages. PMID:9886359

  6. Distributional Assumptions in Educational Assessments Analysis: Normal Distributions versus Generalized Beta Distribution in Modeling the Phenomenon of Learning

    Science.gov (United States)

    Campos, Jose Alejandro Gonzalez; Moraga, Paulina Saavedra; Del Pozo, Manuel Freire

    2013-01-01

    This paper introduces the generalized beta (GB) model as a new modeling tool in the educational assessment area and evaluation analysis, specifically. Unlike normal model, GB model allows us to capture some real characteristics of data and it is an important tool for understanding the phenomenon of learning. This paper develops a contrast with the…

  7. Effects of the Component and Fiber Gradient Distributions on the Strength of Cement-based Composite Materials

    Institute of Scientific and Technical Information of China (English)

    YANG Jiu-jun; HAI Ran; DONG Yan-ling; WU Ke-ru

    2003-01-01

    The effects of the component gradient distribution at interface and the fiber gradient distribution on the strength of cement-based materials were studied.The results show that the flexural strength and compressive strength of the mortar and concrete with interface component and fiber gradient distributions are obviously improved.The strengthes of the fiber gradient distributed mortar and concrete (FGDM/C) are higher than those of fiber homogeneously distributed mortar and concrete (FHDM/C).To obtain the same strength,therefore,a smaller fiber volume content in FGDM/C is needed than that in FHDM/C.The results also show that the component gradient distribution of the concrete can be obtained by means of multi-layer vibrating formation.

  8. MCNP(TM) Release 6.1.1 beta: Creating and Testing the Code Distribution

    Energy Technology Data Exchange (ETDEWEB)

    Cox, Lawrence J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Casswell, Laura [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-06-12

    This report documents the preparations for and testing of the production release of MCNP6™1.1 beta through RSICC at ORNL. It addresses tests on supported operating systems (Linux, MacOSX, Windows) with the supported compilers (Intel, Portland Group and gfortran). Verification and Validation test results are documented elsewhere. This report does not address in detail the overall packaging of the distribution. Specifically, it does not address the nuclear and atomic data collection, the other included software packages (MCNP5, MCNPX and MCNP6) and the collection of reference documents.

  9. Neutron diffraction analysis of residual strain/stress distribution in the vicinity of high strength welds

    Directory of Open Access Journals (Sweden)

    Hamák I.

    2010-06-01

    Full Text Available Residual stresses resulting from non homogeneous heat distribution during welding process belong to most significant factor influencing behavior of welded structures. These stresses are responsible for defect occurrence during welding and they are also responsible for crack initiation and propagation at the either static or dynamic load. The significant effect of weld metal chemical composition as well as the effect of fatigue load and local plastic deformation on residual stress distribution and fatigue life have been recognized for high strength steels welds. The changes in residual stress distribution have then positive effect on cold cracking behavior and also on fatigue properties of the welds [1-3]. Several experimental methods, both destructive and non-destructive, such as hole drilling method, X-ray diffraction, neutron diffraction and others, have been used to examine residual stress distribution in all three significant orientations in the vicinity of the welds. The present contribution summarizes the results of neutron diffraction measurements of residual stress distribution in the vicinity of single-pass high-strength-steel welds having different chemical composition as well as the influence of fatigue load and local plastic deformation. It has been observed that the chemical composition of the weld metal has a significant influence on the stress distribution around the weld. Similarly, by aplying both cyclic load or pre-stress load on the specimens, stress relaxation was observed even in the region of approximately 40 mm far from the weld toe.

  10. Hexadecapole strength distributions of vibrational nuclei in the A=100 mass region

    International Nuclear Information System (INIS)

    Proton and deuteron inelastic scattering data taken in a high-energy resolution measurement have been used to study Jπ=4+ states of some vibrational and transitional nuclei with mass between 94 and 112. Most of the levels up to about 4 MeV excitation energy have been resolved and several new 4+ assignments are proposed by comparing measured angular distributions with coupled-channels calculations. The hexadecapole strength is found to be highly fragmented and tends to concentrate in a cluster of levels around 2.5-3 MeV in approaching the more collective nuclei in an isotopic series. This is in contrast with the behaviour of the quadrupole and octupole strengths in the same nuclei which are mostly concentrated in the first 2+ and 3- levels, respectively. The hexadecapole distributions are compared with IBM-1 calculations in the sdg boson scheme. (orig.)

  11. An assessment of burst strength distribution data for monitoring quality of condom stocks in developing countries.

    Science.gov (United States)

    Free, M J; Hutchings, J; Lubis, F; Natakusumah, R

    1986-03-01

    Laboratory tests were conducted on condoms to examine the changes that occur over time in indicators of condom burst strength, and to determine the relationship between laboratory-assessed condom burst strength and breakage during use in a developing country setting. Three groups of unaged condoms purchased directly from the manufacturer were used: one group exposed to UV light for 10 hours; one group exposed for five hours; and one group unexposed. A sample of each of these groups was tested according to ISO condom air burst test protocols. The remaining condoms were individually packaged in coded polyethylene bags for shipment to the developing country study site. Also used in the study was a group of condoms that had been aged for over 40 months under field conditions in a tropical climate; a sample from this group was tested by the ISO air burst test protocol and the remainder distributed to the study site. One-hundred-thirty Indonesian urban males participated in the double-blind study. Volunteers were not relying on the condom for contraceptive purposes. Each volunteer was given one individually packaged untreated condom, one condom from each treatment group, and four condoms aged in the field. Study participants were instructed to return all used condoms. Each condom that was returned after use was examined for breakage, and the unbroken condoms were subjected to an air inflation test to determine volume and pressure at burst. A comparison of the air burst volume data for a sample of unused and used condoms from the same treatment group indicates that most of the condoms that broke during use had air burst volumes below 11 liters. Therefore, a significant downward shift in the burst strength distribution as measured in the laboratory is likely to result in an increased breakage rate during use. A Condom Deterioration Index calculated from regular periodic testing of stored condom stocks is a convenient and sensitive means of monitoring trends in the

  12. Strength distribution at interface of rotary-friction-welded aluminum to nodular cast iron

    Institute of Scientific and Technical Information of China (English)

    SONG Yu-lai; LIU Yao-hui; ZHU Xian-yong; YU Si-rong; ZHANG Ying-bo

    2008-01-01

    The morphology, size and composition of intermetallic compound at the interface of Al 1050 and nodular cast iron were studied by electron microprobe analysis(EMPA) and scan electron microscopy (SEM), respectively. The bond strength of the interface was measured by the tensile tests and the morphology of the fracture surface was observed by SEM. The observation of the interface reveals that there are two distinct morphologies: no intermetallic compound exists in the central area at the interface; while numbers of intermetallic compounds (FexAly) are formed in the peripheral area due to the overfull heat input. The tensile tests indicate that the distribution of strength in radial direction at the interface is inhomogeneous, and the central area of the interface performs greater bond strength than the peripheral area, which proves directly that the FexAly intermetallic compounds have a negative effect on the integration of interface. The morphology on the fracture surface shows that the facture in the central area at the interface has characteristic of the ductile micro-void facture. So it is important to restrain the form of the intermetallic compound to increase the bond strength of the Al 1050 and nodular cast iron by optimizing welding parameters and the geometry of components.

  13. Adhesively bonded joints composed of pultruded adherends: Considerations at the upper tail of the material strength statistical distribution

    Energy Technology Data Exchange (ETDEWEB)

    Vallee, T.; Keller, Th. [Ecole Polytech Fed Lausanne, CCLab, CH-1015 Lausanne, (Switzerland); Fourestey, G. [Ecole Polytech Fed Lausanne, IACS, Chair Modeling and Sci Comp, CH-1015 Lausanne, (Switzerland); Fournier, B. [CEA SACLAY ENSMP, DEN, DANS, DMN, SRMA, LC2M, F-91191 Gif Sur Yvette, (France); Correia, J.R. [Univ Tecn Lisbon, Inst Super Tecn, Civil Engn and Architecture Dept, P-1049001 Lisbon, (Portugal)

    2009-07-01

    The Weibull distribution, used to describe the scaling of strength of materials, has been verified on a wide range of materials and geometries: however, the quality of the fitting tended to be less good towards the upper tail. Based on a previously developed probabilistic strength prediction method for adhesively bonded joints composed of pultruded glass fiber-reinforced polymer (GFRP) adherends, where it was verified that a two-parameter Weibull probabilistic distribution was not able to model accurately the upper tail of a material strength distribution, different improved probabilistic distributions were compared to enhance the quality of strength predictions. The following probabilistic distributions were examined: a two-parameter Weibull (as a reference), m-fold Weibull, a Grafted Distribution, a Birnbaum-Saunders Distribution and a Generalized Lambda Distribution. The Generalized Lambda Distribution turned out to be the best analytical approximation for the strength data, providing a good fit to the experimental data, and leading to more accurate joint strength predictions than the original two-parameter Weibull distribution. It was found that a proper modeling of the upper tail leads to a noticeable increase of the quality of the predictions. (authors)

  14. Modeling the material strength and equations of state of beta-HMX from both first-principles calculations and molecular dynamics simulations

    Science.gov (United States)

    Peng, Qing; Wang, Guangyu; Liu, G. R.; de, Suvranu

    2015-06-01

    We investigate the elastic constants and equations of state (EOS) of the β-polymorph of cyclotetramethylene tetranitramine (HMX) energetic molecular crystal using density functional theory (DFT) calculations. The combination of vdW-DF2 van der Waals functionals and PBE exchange-correlation functionals gives optimized results. The DFT results are used to optimize the Reactive Force Field (ReaxFF). The material strength and EOS of beta-HMX at finite temperatures are then predicted from ReaxFF molecular dynamics simulations. Our results suggest that the optimized ReaxFF predicts the mechanics and EOS of beta-HMX well. The authors would like to acknowledge the generous financial support from the Defense Threat Reduction Agency (DTRA) Grant # HDTRA1-13-1-0025.

  15. Curve fitting of the corporate recovery rates: the comparison of Beta distribution estimation and kernel density estimation.

    Directory of Open Access Journals (Sweden)

    Rongda Chen

    Full Text Available Recovery rate is essential to the estimation of the portfolio's loss and economic capital. Neglecting the randomness of the distribution of recovery rate may underestimate the risk. The study introduces two kinds of models of distribution, Beta distribution estimation and kernel density distribution estimation, to simulate the distribution of recovery rates of corporate loans and bonds. As is known, models based on Beta distribution are common in daily usage, such as CreditMetrics by J.P. Morgan, Portfolio Manager by KMV and Losscalc by Moody's. However, it has a fatal defect that it can't fit the bimodal or multimodal distributions such as recovery rates of corporate loans and bonds as Moody's new data show. In order to overcome this flaw, the kernel density estimation is introduced and we compare the simulation results by histogram, Beta distribution estimation and kernel density estimation to reach the conclusion that the Gaussian kernel density distribution really better imitates the distribution of the bimodal or multimodal data samples of corporate loans and bonds. Finally, a Chi-square test of the Gaussian kernel density estimation proves that it can fit the curve of recovery rates of loans and bonds. So using the kernel density distribution to precisely delineate the bimodal recovery rates of bonds is optimal in credit risk management.

  16. Pore size distribution, strength, and microstructure of portland cement paste containing metal hydroxide waste

    Energy Technology Data Exchange (ETDEWEB)

    Majid, Z.A.; Mahmud, H.; Shaaban, M.G.

    1996-12-31

    Stabilization/solidification of hazardous wastes is used to convert hazardous metal hydroxide waste sludge into a solid mass with better handling properties. This study investigated the pore size development of ordinary portland cement pastes containing metal hydroxide waste sludge and rice husk ash using mercury intrusion porosimetry. The effects of acre and the addition of rice husk ash on pore size development and strength were studied. It was found that the pore structures of mixes changed significantly with curing acre. The pore size shifted from 1,204 to 324 {angstrom} for 3-day old cement paste, and from 956 to 263 {angstrom} for a 7-day old sample. A reduction in pore size distribution for different curing ages was also observed in the other mixtures. From this limited study, no conclusion could be made as to any correlation between strength development and porosity. 10 refs., 6 figs., 3 tabs.

  17. A Bayesian beta distribution model for estimating rainfall IDF curves in a changing climate

    Science.gov (United States)

    Lima, Carlos H. R.; Kwon, Hyun-Han; Kim, Jin-Young

    2016-09-01

    The estimation of intensity-duration-frequency (IDF) curves for rainfall data comprises a classical task in hydrology studies to support a variety of water resources projects, including urban drainage and the design of flood control structures. In a changing climate, however, traditional approaches based on historical records of rainfall and on the stationary assumption can be inadequate and lead to poor estimates of rainfall intensity quantiles. Climate change scenarios built on General Circulation Models offer a way to access and estimate future changes in spatial and temporal rainfall patterns at the daily scale at the utmost, which is not as fine temporal resolution as required (e.g. hours) to directly estimate IDF curves. In this paper we propose a novel methodology based on a four-parameter beta distribution to estimate IDF curves conditioned on the observed (or simulated) daily rainfall, which becomes the time-varying upper bound of the updated nonstationary beta distribution. The inference is conducted in a Bayesian framework that provides a better way to take into account the uncertainty in the model parameters when building the IDF curves. The proposed model is tested using rainfall data from four stations located in South Korea and projected climate change Representative Concentration Pathways (RCPs) scenarios 6 and 8.5 from the Met Office Hadley Centre HadGEM3-RA model. The results show that the developed model fits the historical data as good as the traditional Generalized Extreme Value (GEV) distribution but is able to produce future IDF curves that significantly differ from the historically based IDF curves. The proposed model predicts for the stations and RCPs scenarios analysed in this work an increase in the intensity of extreme rainfalls of short duration with long return periods.

  18. Strength distributions in neodymium isotopes: a test of collective nuclear models

    International Nuclear Information System (INIS)

    Excited states in even Nd isotopes, up to excitation energies of 3-4 MeV, were investigated in proton- and deuteron-scattering experiments performed with high-energy resolution. More than 300 transitions were studied. For several new excited states spin and parity assignments have been suggested. Reduced transition probabilities were extracted for natural-parity states from 0+ up to 6+. The experimental strength distributions have been compared with the predictions of the interacting boson model (IBM) and of the quasi-particle-phonon model (QPM). The octupole transition probabilities are well described in both models as produced by the fragmentation of the f-boson or of E3 phonons. IBM-sdf calculations seem to account also for the transitions to the low-lying 1-states. Quadrupole and hexadecapole distributions are well described in the QPM. The leading configurations are due to 6-8 low-lying one-phonon states. The two- and three-phonon states play an important role especially in 146Nd. The failure of IBM quadrupole and hexadecapole calculations clearly points out the need of introducing additional bosons lying at high excitation energies. QPM evaluations account also for other features of the experimental data, as the E5 and E6 strength distributions and the isovector components. The limits of the two models are discussed. (orig.)

  19. Gamow-Teller strength distributions for neutron-rich nitrogen, oxygen and fluorine isotopes

    Science.gov (United States)

    Zhang, Yu-Mei

    2016-08-01

    Gamow-Teller transition properties for neutron-rich nitrogen, oxygen and fluorine isotopes are studied in integrated energy. The structures of these nuclei are described by means of nuclear shell model with the WBT interaction in the p-sd shell space. Calculations of the Gamow-Teller strength distribution reproduce the experimental data reasonably in the low-energy region. For the dripline nucleus 24O, a super Gamow-Teller transition to a single state at excitation energy of 14.72 MeV in 24F is predicted. β-decay half-lives for these nuclei are calculated and compared with the available experimental data.

  20. Interval Estimation of Stress-Strength Reliability Based on Lower Record Values from Inverse Rayleigh Distribution

    Directory of Open Access Journals (Sweden)

    Bahman Tarvirdizade

    2014-01-01

    Full Text Available We consider the estimation of stress-strength reliability based on lower record values when X and Y are independently but not identically inverse Rayleigh distributed random variables. The maximum likelihood, Bayes, and empirical Bayes estimators of R are obtained and their properties are studied. Confidence intervals, exact and approximate, as well as the Bayesian credible sets for R are obtained. A real example is presented in order to illustrate the inferences discussed in the previous sections. A simulation study is conducted to investigate and compare the performance of the intervals presented in this paper and some bootstrap intervals.

  1. Span-Dependent Distributions of the Bending Strength of Spruce Timber

    DEFF Research Database (Denmark)

    Ditlevsen, Ove; Källsner, Bo

    2005-01-01

    of the large test series is that unintentionally the data became randomly censored upwards. This censoring of the data rules out both the moment estimation method and the maximum likelihood method. Instead valid parameter estimates can be obtained by maximizing the posterior density defined as the...... likelihood function multiplied by a suitably chosen non-informative prior density (MP-method). Subsequently using bias factors assessed by simulation ensures that the corrected MP-estimates are unbiased. A closed form analytical expression for the distribution function of the bending strength of a beam with...

  2. On the Fermi and Gamow-Teller strength distribution in medium-heavy mass nuclei

    CERN Document Server

    Rodin, V A

    2003-01-01

    The BCS model is incorporated in the Continuum-Random-Phase-Approximation (CRPA) method to formulate a version of the partially self-consistent pn-quasiparticle CRPA (QCRPA) approach. Within the approach the Fermi and Gamow-Teller strength distributions in single- and double- closed-shell nuclei are calculated for a wide excitation energy interval, including the region of the isovector monopole and spin-monopole giant resonances. The isospin and configurational splittings of the Gamow-Teller resonance are also analyzed. The results obtained for $^{90}$Nb, the Sb isotopes and $^{208}$Bi are compared with available experimental data.

  3. A preliminary optical and electron microscopic study of the beta(1) integrin distribution pattern of human osteosarcoma-derived cells.

    Science.gov (United States)

    Banai, Kiarash; Brady, Ken; McDonald, Fraser

    2004-07-01

    Immunogold labelling was used to study the organisation of the beta(1) integrins on osteosarcoma-derived osteoblasts (Saos-2 and MG-63). Monolayers of cells were prepared in multiwell culture plates on both uncovered and collagen-covered coverslips, and beta(1) integrins were primarily labelled using mouse monoclonal antibodies to beta(1) integrins. Indirect immunofluorescence labels using an anti-mouse fluorescein-conjugated goat antibody showed an even distribution of the beta(1) integrins on the cell membranes of all cell types used. A concentration of 2 microg/ml of the primary antibodies and a 1:100 dilution of the secondary antibodies were determined as the optimal concentration for labelling to use with indirect localisation of the primary antibodies gold conjugated to goat anti-mouse antibodies and viewed under an electron microscope. Ten nanometre gold particles were used for transmission electron microscopy (TEM) and 40 nm gold particles for scanning electron microscopy. TEM showed that beta(1) integrins were mainly clustered on the cell membrane processes with less labelling on the cell membranes themselves. The distribution of beta(1) integrins on osteosarcoma cells supports the concept that integrins may function by forming focal adhesions at the site of the cytoplasmic membrane processes. PMID:15241608

  4. Gamow-Teller (GT$\\pm$) strength distributions of $^{56}Ni$ for ground and excited states

    CERN Document Server

    Nabi, Jameel-Un; Sajjad, Muhammad

    2016-01-01

    Gamow-Teller (GT) transitions play an important and consequential role in many astrophysical phenomena. These include, but are not limited to, electron and positron capture rates which determine the fate of massive stars and play an intricate role in the dynamics of core collapse. These $GT_{\\pm}$ transitions rates are the significant inputs in the description of supernova explosions. $GT_{\\pm}$ strength function values are sensitive to the $^{56}Ni$ core excitation in the middle \\textit{pf}-shell region and to the size of the model space as well. We used the pn-QRPA theory for extracting the GT strength for ground and excited states of $^{56}Ni$. We then used these GT strength distributions to calculate the electron \\textit{and} positron capture rates which show differences with the earlier calculations. One curious finding of this paper is our enhanced electron capture rates on $^{56}Ni$ at presupernova temperatures. These differences need to be taken into account for the modeling of the early stages of Typ...

  5. Gamow-Teller strength distributions at finite temperatures and electron capture in stellar environments

    CERN Document Server

    Dzhioev, Alan A; Ponomarev, V Yu; Wambach, J; Langanke, K; Martínez-Pinedo, G

    2009-01-01

    We propose a new method to calculate stellar weak-interaction rates. It is based on the Thermo-Field-Dynamics formalism and allows the calculation of the weak-interaction response of nuclei at finite temperatures. The thermal evolution of the GT$_+$ distributions is presented for the sample nuclei $^{54, 56}$Fe and ~$^{76,78,80}$Ge. For Ge we also calculate the strength distribution of first-forbidden transitions. We show that thermal effects shift the GT$_+$ centroid to lower excitation energies and make possible negative- and low-energy transitions. In our model we demonstrate that the unblocking effect for GT$_+$ transitions in neutron-rich nuclei is sensitive to increasing temperature. The results are used to calculate electron capture rates and are compared to those obtained from the shell model.

  6. Distribution of spin dipole transition strength in the 15N(n,p)15C reaction

    International Nuclear Information System (INIS)

    The reaction 15N(n,p)15C was studied at a neutron energy of 288 MeV using the TRIUMF (n,p) charge exchange facility and a high pressure gas target. The angular distributions for spin dipole (ΔL=1) transitions to the states in 15C at energies 0 MeV and 0.740 MeV, as well as for higher excitation energies, were measured and the results were compared with DWIA calculations. The measured distribution of the spin dipole strength agrees well with shell model predictions, indicating that a rather simple model provides a satisfactory description of the 15N ground state, and of positive parity states in 15C up to about 18 MeV excitation. The magnitude of the peak cross sections (at ≅ 7 degrees) is described well by the calculations when the theoretical cross section is renormalized by a factor 0.7. The calculated cross sections near zero degrees are generally smaller than experimental data. It this is a general feature of ΔL=1 transitions, it suggests that estimates of GT strength based on a multipole decomposition of measured cross sections may be too high. (Author) (41 refs., 3 tabs., 14 figs.)

  7. Assessing the gluten content in wheat as an expression of the nutrition deficit, through beta distribution

    Science.gov (United States)

    Pîslea, Daniela; Boldea, Marius; Sala, Florin

    2013-10-01

    The laboratory analysis of the gluten content of wheat in relation to the doses of nitrogen, phosphorus and potassium used for fertilizing the soil reveals positive correlation between the two variables. The gluten content in wheat grains is an extremely important quality index in bread manufacturing. One of the farmers' objectives is to obtain high values of this index. The quality of bread manufacturing products is very sensitive to any changes in the percentage share of this indicator. The minimum limit of gluten accepted for bread manufacturing is 26%; even a small variation, of one percentage, of gluten, over this limit, changes the quality of the wheat yield, with considerable effects on the quality of bread. Therefore, farmers are interested in using crop technologies and especially fertilization in order to obtain wheat with high gluten content. Of the nutritive macronutrients, nitrogen plays a significant role in ensuring high gluten content. The definition domain of the measurements is (0;1). This ratio is not constant, but it has a tendency towards a certain medium value, depending on the chemical fertilizers, on fertilization. It follows that the statistic distribution which evaluates the phenomenon is the beta distribution.

  8. Influence of reprocessing on fibre length distribution, tensile strength and impact strength of injection moulded cellulose fibre-reinforced polylactide (PLA composites

    Directory of Open Access Journals (Sweden)

    N. Graupner

    2016-08-01

    Full Text Available The present study focuses on the reprocessing behaviour of recycled injection moulded polylactide (PLA composites. The composites are reinforced with regenerated cellulose fibres (lyocell of variable fineness and a fibre mass content of 30%. They were reprocessed up to three times. The influence of reprocessing on the fibre length distribution and the resulting composite mechanical properties (tensile and impact strength was analysed. While the first reprocessing cycle does not affect the mechanical characteristics of the neat PLA matrix, the strength of the composites decreases significantly due to a decreasing fibre aspect ratio. It was shown that fibres having a larger cross-sectional area display a lower aspect ratio than finer fibres, after reprocessing. This phenomenon leads to a larger decrease in tensile strength of composites reinforced with coarser fibres when compared to composites reinforced with finer fibres. A comparison of virgin composites and threefold reprocessed composites with a similar fibre length distribution resulted in a significantly higher tensile strength compared to the virgin sample. This result leads to the conclusion that not only the fibre length is drastically reduced by reprocessing but also that the fibres and the matrix were damaged.

  9. Coexistence of beta 1- and beta 2-adrenoceptors in the rabbit heart: quantitative analysis of the regional distribution by (-)-3H-dihydroalprenolol binding

    International Nuclear Information System (INIS)

    We determined the amount of beta 1- and beta 2-adrenoceptors in right and left atria and ventricles of rabbits. For this purpose inhibition of specific (-)-3H-dihydroalprenolol [(-)-3H-DHA] binding (5 nM) by beta 1-selective (practolol, metoprolol) and beta 2-selective (zinterol, IPS 339) adrenergic drugs was determined and analyzed by pseudo-Scatchard (Hofstee) plots. For both atria, inhibition of binding by the four selective beta-adrenergic drugs resulted in non-linear Hofstee plots, suggesting the coexistence of both beta-adrenoceptor subtypes. From these plots we calculated a beta 1:beta 2-adrenoceptor ratio of 72:28 for the right atrium and of 82:18 for the left. In contrast, only a very small amount of beta 2-adrenoceptors (approximately 5-7% of the total beta-adrenoceptor population) could be detected in the ventricles. For comparison we analyzed the inhibition of specific (-)-3H-DHA binding in tissues with homogeneous population of beta-adrenoceptors (beta 1:guinea pig left ventricle; beta 2: cerebellum of mature rats). For both tissues the four selective beta-adrenergic drugs showed linear Hofstee plots, demonstrating that in tissues with homogeneous beta-receptor population interaction of each drug with the receptor followed simple mass-action kinetics. We conclude that beta 1- and beta 2-adrenoceptors coexist in rabbit atria while the ventricles are predominantly endowed the beta 1-adrenoceptors

  10. Coexistence of beta 1- and beta 2-adrenoceptors in the rabbit heart: quantitative analysis of the regional distribution by (-)-/sup 3/H-dihydroalprenolol binding

    Energy Technology Data Exchange (ETDEWEB)

    Brodde, O.E.; Leifert, F.J.; Krehl, H.J.

    1982-01-01

    We determined the amount of beta 1- and beta 2-adrenoceptors in right and left atria and ventricles of rabbits. For this purpose inhibition of specific (-)-/sup 3/H-dihydroalprenolol ((-)-/sup 3/H-DHA) binding (5 nM) by beta 1-selective (practolol, metoprolol) and beta 2-selective (zinterol, IPS 339) adrenergic drugs was determined and analyzed by pseudo-Scatchard (Hofstee) plots. For both atria, inhibition of binding by the four selective beta-adrenergic drugs resulted in non-linear Hofstee plots, suggesting the coexistence of both beta-adrenoceptor subtypes. From these plots we calculated a beta 1:beta 2-adrenoceptor ratio of 72:28 for the right atrium and of 82:18 for the left. In contrast, only a very small amount of beta 2-adrenoceptors (approximately 5-7% of the total beta-adrenoceptor population) could be detected in the ventricles. For comparison we analyzed the inhibition of specific (-)-/sup 3/H-DHA binding in tissues with homogeneous population of beta-adrenoceptors (beta 1:guinea pig left ventricle; beta 2: cerebellum of mature rats). For both tissues the four selective beta-adrenergic drugs showed linear Hofstee plots, demonstrating that in tissues with homogeneous beta-receptor population interaction of each drug with the receptor followed simple mass-action kinetics. We conclude that beta 1- and beta 2-adrenoceptors coexist in rabbit atria while the ventricles are predominantly endowed the beta 1-adrenoceptors.

  11. Habitat heterogeneity drives the geographical distribution of beta diversity: the case of New Zealand stream invertebrates

    OpenAIRE

    Astorga, Anna; Death, Russell; Death, Fiona; Paavola, Riku; Chakraborty, Manas; Muotka, Timo

    2014-01-01

    To define whether the beta diversity of stream invertebrate communities in New Zealand exhibits geographical variation unexplained by variation in gamma diversity and, if so, what mechanisms (productivity, habitat heterogeneity, dispersal limitation, disturbance) best explain the observed broad-scale beta diversity patterns. We sampled 120 streams across eight regions (stream catchments), spanning a north–south gradient of 12° of latitude, and calculated beta diversity (with both species rich...

  12. Impact of Blending on Strength Distribution of Ambient Cured Metakaolin and Palm Oil Fuel Ash Based Geopolymer Mortar

    Directory of Open Access Journals (Sweden)

    Taliat Ola Yusuf

    2014-01-01

    Full Text Available This paper investigates the influence of blending of metakaolin with silica rich palm oil fuel ash (POFA on the strength distribution of geopolymer mortar. The broadness of strength distribution of quasi-brittle to brittle materials depends strongly on the existence of flaws such as voids, microcracks, and impurities in the material. Blending of materials containing alumina and silica with the objective of improving the performance of geopolymer makes comprehensive characterization necessary. The Weibull distribution is used to study the strength distribution and the reliability of geopolymer mortar specimens prepared from 100% metakaolin, 50% and 70% palm and cured under ambient condition. Mortar prisms and cubes were used to test the materials in flexure and compression, respectively, at 28 days and the results were analyzed using Weibull distribution. In flexure, Weibull modulus increased with POFA replacement, indicating reduced broadness of strength distribution from an increased homogeneity of the material. Modulus, however, decreased with increase in replacement of POFA in the specimens tested under compression. It is concluded that Weibull distribution is suitable for analyses of the blended geopolymer system. While porous microstructure is mainly responsible for flexural failure, heterogeneity of reaction relics is responsible for the compression failure.

  13. The astrophysical r-process and its dependence on properties of nuclei far from stability: Beta strength functions and neutron capture rates

    International Nuclear Information System (INIS)

    The question of the astrophysical site of the rapid neutron capture (r-) process which is believed to be responsible for the production of the heavy elements in the universe has been a problem in astrophysics for more than two decades. The solution of this problem is not only dependent on the development of realistic astrophysical supernova models, i.e. correct treatment of the hydrodynamics of gravitational collapse and supernova explosion and the equation of state of hot and dense matter, but is shown in this paper to be very sensitive also to 'standard' nuclear physics properties of nuclei far from stability such as beta decay properties and neutron capture rates. For both of the latter, strongly oversimplifying assumptions, not applying the development in nuclear physics during the last decade, have been made in almost all r-process calculations performed up to now. A critical discussion of the state of the art of such calculations seems therefore to be indicated. In this paper procedures are described which allow one to obtain: 1) β-decay properties (decay rates, β-delayed neutron emissions and fission rates); 2) neutron capture rates for neutron-rich nuclei considerably improved over what has been used up to now. The beta strength functions are calculated for approx. equal to6000 nuclei between beta stability line and neutron drip line. By hydrodynamical supernova explosion calculations using realistic stellar models it is shown that as a consequence of the improved β-rates explosive He burning is a convincing alternative site to the 'classical' r-process whose existence still is questionable. The new β-rates will be important also for the investigation of further astrophysical sites producing heavy elements such as the r(n)-processes in explosive C or Ne burning. (orig.)

  14. Non-destructive residual stress distribution measurement in nano-structured ultrahigh-strength gear steels

    International Nuclear Information System (INIS)

    The well-established enhanced fatigue performance associated with beneficial compressive residual stresses has been broadly applied in the development of new engineering materials, particularly gear and bearing steels. Residual stress enhancement processes, such as shot/laser peening, have also been investigated to maximize their benefits on fatigue strength. However, the measurement of residual stress distributions still heavily relies on the conventional X-ray technique, involving destructive material removal, tedious data correction and time-consuming data collection, which slows new material design and process optimization. To overcome this problem, we employ novel, non-destructive synchrotron techniques with high-energy x-rays to measure the distribution of residual strain/stress in a laser-peened, ultrahigh-strength gear steel. This study will assist in process optimization, to achieve the desired residual stresses for selected applications. X-ray measurements were performed at the 1-ID beamline at the Advanced Photon Source (APS), Argonne National Laboratory. An x-ray energy of 76 keV and conical slit were used to create a diffraction volume of ∼ 20 x 20 x 150(micro)m3. An area detector was placed after the conical slit to collect diffraction over a plane encompassing (nearly) the axial and normal strain directions. Cylindrical specimens (76 mm long, 9.525 mm diameter) were rotated during the measurement to ensure a sufficiently large number of grains were irradiated. The steel, FerriumC67(regsign), was designed utilizing thermodynamics-based strengthening models to achieve a new level of case hardness (67 HRc) and good core toughness, employing a 3nm M2C carbide dispersion. After heat treatment, C67 was laser peened and subject to rolling contact fatigue (RCF) screening tests under the extreme Hertzian contact stress of 5.4 GPa. Both regions away from ('untested') and under wear tracks were studied for comparison. Four BCC reflections from martensite

  15. Presumption of the energy-spectrum of high-energy electron beam based on the beta-distribution model

    International Nuclear Information System (INIS)

    The energy spectra of high-energy electron beams used in radiotherapy are the most important data for evaluating absorbed doses and/or dose distributions in the body of a patient. However, it is impossible to measure the actual spectra of a high-energy electron beam. In this study, we suggest a method to presume the spectra of high-energy electron beams by use of the beta distribution model. The procedure of this method is as follows: (1) the spectrum of the high-energy electron beam was assumed to have a maximum energy Emax, and α, β parameters of the beta probability density function. (2) The percentage depth dose (PDD) based on the assumed spectrum was calculated by a Monte Carlo simulation. (3) The best matching energy spectrum was searched in comparison with the experimental PDD curves. Finally, the optimal energy spectrum of the electron beam was estimated after reiterating the process from (1) to (3). With our method, the measured PDD curves were optimally simulated following the experimental data. It appeared that the assumed spectra approximated well to the actual spectra. However, the error between the assumed and experimental data was observed in the region under the incident surface. We believe this was due to the influence of low-energy electrons scattered at installed collimators, etc. In order to simulate PDDs in this region accurately, a further correction process is required for a spectrum based on the beta distribution model. (author)

  16. Credible Intervals for Precision and Recall Based on a K-Fold Cross-Validated Beta Distribution.

    Science.gov (United States)

    Wang, Yu; Li, Jihong

    2016-08-01

    In typical machine learning applications such as information retrieval, precision and recall are two commonly used measures for assessing an algorithm's performance. Symmetrical confidence intervals based on K-fold cross-validated t distributions are widely used for the inference of precision and recall measures. As we confirmed through simulated experiments, however, these confidence intervals often exhibit lower degrees of confidence, which may easily lead to liberal inference results. Thus, it is crucial to construct faithful confidence (credible) intervals for precision and recall with a high degree of confidence and a short interval length. In this study, we propose two posterior credible intervals for precision and recall based on K-fold cross-validated beta distributions. The first credible interval for precision (or recall) is constructed based on the beta posterior distribution inferred by all K data sets corresponding to K confusion matrices from a K-fold cross-validation. Second, considering that each data set corresponding to a confusion matrix from a K-fold cross-validation can be used to infer a beta posterior distribution of precision (or recall), the second proposed credible interval for precision (or recall) is constructed based on the average of K beta posterior distributions. Experimental results on simulated and real data sets demonstrate that the first credible interval proposed in this study almost always resulted in degrees of confidence greater than 95%. With an acceptable degree of confidence, both of our two proposed credible intervals have shorter interval lengths than those based on a corrected K-fold cross-validated t distribution. Meanwhile, the average ranks of these two credible intervals are superior to that of the confidence interval based on a K-fold cross-validated t distribution for the degree of confidence and are superior to that of the confidence interval based on a corrected K-fold cross-validated t distribution for the

  17. Permeability and pore size distribution in medium strength self-compacting concrete

    OpenAIRE

    Fernández Cánovas, M.; Gálvez, J. C.; Moragues, A.; Bermejo, E. B.

    2010-01-01

    The use of self-compacting concrete (SCC) has been on the rise in recent years. Research on this type of concrete has focused primarily on determining optimal dosage, while durability, particularly for medium strength SCC, has received much less attention. The present study explored the permeability of a number of medium strength (characteristic strength, 30 MPa) self-compacting concretes, including SCCs made with common cement, in pursuit of a balance between performance and cost....

  18. Structure effects in the calculation of beta strength functions and half lives of Rb and Br isotopes

    International Nuclear Information System (INIS)

    The properties of beda delayed neutron emission of the precursors around mass 95 are investigated using spherical Shell Model plus pairing. The objective of this work is to find out the important parameters that effect these properties. The strength functions and half lives of both even and odd Rb and Br precursors are calculated in BCS quasi-particle theory as well as in Seniority Truncated Exact Diagonalization (STED) scheme. The calculated half lives from the two schemes are in close agreement with each other. STED gave much smoother overall trend which is in better agreement with experimental values. The calculations reveal that the so called 'odd decays' which depend in an essential way on the parent ground state configuration are of crucial importance in determining both half life, t/sub 1/2/ and delayed neutron emission probability, P/sub n/. Furthermore, it is shown that it is not possible to choose apriori global set for the single particle Shell model basis to predict the correct ground state configurations for both the odd and even nuclei. Instead, it is necessary to examine available experimental evidence in order to construct a more valid global set for single particle basis. The significant variations of the predicted half lives according to the different parent ground-state configuration choices, reveal the importance of nuclear structure effects in these isotopes. The calculated t/sub 1/2/ and P/sub n/ of Rb and Br precursors are presented, discussed and compared with experimental values

  19. Existence of a threshold for brittle grains crushing strength: two-versus three- parameter Weibull distribution fitting

    OpenAIRE

    Stefanou, Ioannis; Sulem, Jean

    2015-01-01

    International audience Grain crushing plays an important role in the mechanical behavior of granular media, in chemo-hydro-thermo-mechanical couplings, in instabilities related to strain localization such as shear bands and compaction bands, in geophysical and geotechnical processes, in reservoir and petroleum engineering and in many other domains. The strength of brittle particles seems to be quite well described by a two-parameter Weibull distribution. Nevertheless, such a distribution p...

  20. The hyperbolic effect of density and strength of inter beta-cell coupling on islet bursting: a theoretical investigation

    Directory of Open Access Journals (Sweden)

    Wang Xujing

    2008-08-01

    Full Text Available Abstract Background Insulin, the principal regulating hormone of blood glucose, is released through the bursting of the pancreatic islets. Increasing evidence indicates the importance of islet morphostructure in its function, and the need of a quantitative investigation. Recently we have studied this problem from the perspective of islet bursting of insulin, utilizing a new 3D hexagonal closest packing (HCP model of islet structure that we have developed. Quantitative non-linear dependence of islet function on its structure was found. In this study, we further investigate two key structural measures: the number of neighboring cells that each β-cell is coupled to, nc, and the coupling strength, gc. Results β-cell clusters of different sizes with number of β-cells nβ ranging from 1–343, nc from 0–12, and gc from 0–1000 pS, were simulated. Three functional measures of islet bursting characteristics – fraction of bursting β-cells fb, synchronization index λ, and bursting period Tb, were quantified. The results revealed a hyperbolic dependence on the combined effect of nc and gc. From this we propose to define a dimensionless cluster coupling index or CCI, as a composite measure for islet morphostructural integrity. We show that the robustness of islet oscillatory bursting depends on CCI, with all three functional measures fb, λ and Tb increasing monotonically with CCI when it is small, and plateau around CCI = 1. Conclusion CCI is a good islet function predictor. It has the potential of linking islet structure and function, and providing insight to identify therapeutic targets for the preservation and restoration of islet β-cell mass and function.

  1. Dynamics and spatial distribution of beta-lactamase expression in Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Bagge, N.; Hentzer, Morten; Andersen, Jens Bo; Ciofu, O.; Givskov, Michael Christian; Høiby, N.

    2004-01-01

    The development of resistance to beta-lactam antibiotics is a problem in the treatment of chronic Pseudomonas aeruginosa infection in the lungs of patients with cystic fibrosis. The main resistance mechanism is high-level expression of the chromosomally encoded AmpC beta-lactamase of P. aeruginosa...... cells growing in biofilms. Several genes have been shown to influence the level of ampC expression, but little is known about the regulation of ampC expression in P. aeruginosa biofilms. To study the expression of ampC in P. aeruginosa biofilms, we constructed a reporter that consisted of the fusion of...... the ampC promoter to gfp(ASV) encoding an unstable version of the green fluorescent protein. In vitro biofilms of P. aeruginosa were exposed to the beta-lactam antibiotics imipenem and ceftazidime. Sub-MICs of imipenem significantly induced the monitor system of the biofilm bacteria in the peripheries...

  2. Analytical approximation of the dose distribution from point beta-sources

    International Nuclear Information System (INIS)

    A new method for analytical calculation of the beta-ray dose from point sources which accounts for the total beta-spectrum shape are presented and the results are compared to calculations of Loevinger and the Monte-Carlo groups. The most important feature is that it can be used for the resultant sum of several spectra and also for distorted or experimentally measured spectra. The method uses tabulated values for the specific energy lost and calculated or measured values for the shape of the total spectrum from nuclide or mixture of nuclides. The approach have been tested with isotopes with different beta-ray shapes(90Sr, 90Y) and in the presence of conversion electrons - 137Cs. 106Rh is included because of high Emax = 3.54 MeV. The agreement of the proposed method with the Monte-Carlo simulations is very good. The chosen spectra are with very different initial shape, which confirms the applicability of the approach. The major deviation is for the large distances due to the limited accuracy of the Loevinger method. The approach can be used for the soft biological tissue and for other than point sources. For the skin contamination it is necessary the backscattering electrons to be taken into account. An initial version of the approach has been used for calculations of beta-ray doses due to hot particles after the Chernobyl accident

  3. Giant dipole resonance in $^{88}$Mo from phonon damping model's strength functions averaged over temperature and angular momentum distributions

    CERN Document Server

    Dang, N Dinh; Kmiecik, M; Maj, A

    2013-01-01

    The line shapes of giant dipole resonance (GDR) in the decay of the compound nucleus $^{88}$Mo, which is formed after the fusion-evaporation reaction $^{48}$Ti + $^{40}$Ca at various excitation energies $E^{*}$ from 58 to 308 MeV, are generated by averaging the GDR strength functions predicted within the phonon damping model (PDM) using the empirical probabilities for temperature and angular momentum. The average strength functions are compared with the PDM strength functions calculated at the mean temperature and mean angular momentum, which are obtained by averaging the values of temperature and angular momentum using the same temperature and angular-momentum probability distributions, respectively. It is seen that these two ways of generating the GDR linear line shape yield very similar results. It is also shown that the GDR width approaches a saturation at angular momentum $J\\geq$ 50$\\hbar$ at $T=$ 4 MeV and at $J\\geq$ 70$\\hbar$ at any $T$.

  4. Measurement of beta-radioactivity distribution in soil by use of fiber-type radiophotoluminescence glass dosimeter

    International Nuclear Information System (INIS)

    Fiber-type radiophotoluminescence (RPL) glass dosimeters were satisfactorily made from reagent-grade powders of NaPO3, Al(PO3)3 and AgCl for the measurement of beta-radioactivity distribution in soil. The fiber-type glass dosimeters were covered with thin polyethylene film for the protection of the glass dosimeters against direct contact to soil particles. The RPL intensity of fiber-type glass dosimeters was successfully measured with a confocal microscope together with an ultraviolet pulsed laser. Depth-directional radioactive-cesium distribution in soil at Fukushima was well measured with the fiber-type RPL glass dosimeters and the confocal microscope system. -- Highlights: ► Fiber-type radiophotoluminescence (RPL) glass dosimeters were satisfactorily made. ► The RPL intensity of a glass dosimeter was well measured with a laser microscope. ► Radioactive-cesium distribution in soil was well measured with glass dosimeters

  5. Beta Test Plan for Advanced Inverters Interconnecting Distributed Resources with Electric Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Hoke, A.; Chakraborty, S.; Basso, T.; Coddington, M.

    2014-01-01

    This document provides a preliminary (beta) test plan for grid interconnection systems of advanced inverter-based DERs. It follows the format and methodology/approach established by IEEE Std 1547.1, while incorporating: 1. Upgraded tests for responses to abnormal voltage and frequency, and also including ride-through. 2. A newly developed test for voltage regulation, including dynamic response testing. 3. Modified tests for unintentional islanding, open phase, and harmonics to include testing with the advanced voltage and frequency response functions enabled. Two advanced inverters, one single-phase and one three-phase, were tested under the beta test plan. These tests confirmed the importance of including tests for inverter dynamic response, which varies widely from one inverter to the next.

  6. Small-area fiber-coupled scintillation camera for imaging beta-ray distributions intraoperatively

    Science.gov (United States)

    MacDonald, L. R.; Tornai, Martin P.; Levin, C. S.; Park, J.; Atac, Muzaffer; Cline, David B.; Hoffman, Eric G.

    1995-09-01

    A small area, imaging, scintillation probe is being developed for locating small amounts of radio-labeled malignant tissue during surgery. Preliminary in brain surgery, avoiding the removal of excess tissue is a priority. It is possible to locate the main body of a brain tumor both before and during surgery, but once the bulk of the tumor is excised the identification of residual malignant tissue is difficult. A probe that covers an area of 1-2 cm(superscript 2) with an intrinsic resolution of 1-2 mm could locate small tumor masses that pose a threat of recurrence of the disease, and prevent removal of healthy tissue. A pre-operative injection of tumor seeking, beta emitting radiopharmaceutical (e.g. (superscript 18)fluorodeoxyuridine-FDUR-) will label the tumor. The limited range of beta-rays ensures proximity upon successful detection. Plastic scintillators are used for beta detection, and visible light photon counters (VLPCs) detect the scintillation light. For maneuverability in and around the surgical cavity, the scintillators are coupled to the VLPCs via 2 m of optical fiber. An imaging device can cover the tissue bed in a time compatible with surgery, as opposed to a single element detector on the order of 1-2 mm in size with comparable resolution. An imager also distinguishes high background rates (such as from annihilation gammas in FDUR) and concentrations of activity.

  7. Unit-Sphere Anisotropic Multiaxial Stochastic-Strength Model Probability Density Distribution for the Orientation of Critical Flaws

    Science.gov (United States)

    Nemeth, Noel

    2013-01-01

    Models that predict the failure probability of monolithic glass and ceramic components under multiaxial loading have been developed by authors such as Batdorf, Evans, and Matsuo. These "unit-sphere" failure models assume that the strength-controlling flaws are randomly oriented, noninteracting planar microcracks of specified geometry but of variable size. This report develops a formulation to describe the probability density distribution of the orientation of critical strength-controlling flaws that results from an applied load. This distribution is a function of the multiaxial stress state, the shear sensitivity of the flaws, the Weibull modulus, and the strength anisotropy. Examples are provided showing the predicted response on the unit sphere for various stress states for isotropic and transversely isotropic (anisotropic) materials--including the most probable orientation of critical flaws for offset uniaxial loads with strength anisotropy. The author anticipates that this information could be used to determine anisotropic stiffness degradation or anisotropic damage evolution for individual brittle (or quasi-brittle) composite material constituents within finite element or micromechanics-based software

  8. Assessment of ocular beta radiation dose distribution due to 106Ru/106Rh brachytherapy applicators using MCNPX Monte Carlo code

    Directory of Open Access Journals (Sweden)

    Nilseia Aparecida Barbosa

    2014-08-01

    Full Text Available Purpose: Melanoma at the choroid region is the most common primary cancer that affects the eye in adult patients. Concave ophthalmic applicators with 106Ru/106Rh beta sources are the more used for treatment of these eye lesions, mainly lesions with small and medium dimensions. The available treatment planning system for 106Ru applicators is based on dose distributions on a homogeneous water sphere eye model, resulting in a lack of data in the literature of dose distributions in the eye radiosensitive structures, information that may be crucial to improve the treatment planning process, aiming the maintenance of visual acuity. Methods: The Monte Carlo code MCNPX was used to calculate the dose distribution in a complete mathematical model of the human eye containing a choroid melanoma; considering the eye actual dimensions and its various component structures, due to an ophthalmic brachytherapy treatment, using 106Ru/106Rh beta-ray sources. Two possibilities were analyzed; a simple water eye and a heterogeneous eye considering all its structures. Two concave applicators, CCA and CCB manufactured by BEBIG and a complete mathematical model of the human eye were modeled using the MCNPX code. Results and Conclusion: For both eye models, namely water model and heterogeneous model, mean dose values simulated for the same eye regions are, in general, very similar, excepting for regions very distant from the applicator, where mean dose values are very low, uncertainties are higher and relative differences may reach 20.4%. For the tumor base and the eye structures closest to the applicator, such as sclera, choroid and retina, the maximum difference observed was 4%, presenting the heterogeneous model higher mean dose values. For the other eye regions, the higher doses were obtained when the homogeneous water eye model is taken into consideration. Mean dose distributions determined for the homogeneous water eye model are similar to those obtained for the

  9. Residue strength, water absorption and pore size distributions of recycled aggregate concrete after exposure to elevated temperatures

    OpenAIRE

    Kou, Shi-Cong; Poon, Chi-Sun; Etxeberria Larrañaga, Miren

    2014-01-01

    In this paper, the effects of high temperature exposure of recycled aggregate concretes in terms of residual strengths, capillary water absorption capacity and pore size distribution are discussed. Two mineral admixtures, fly ash (FA) and ground granulated blast furnace (GGBS) were used in the experiment to partially replace ordinary Portland cement for concrete production. The water to cementitious materials ratio was maintained at 0.50 for all the concrete mixes. The replacement levels of n...

  10. Effective oscillator strength distributions of spherically symmetric atoms for calculating polarizabilities and long-range atom–atom interactions

    International Nuclear Information System (INIS)

    Effective oscillator strength distributions are systematically generated and tabulated for the alkali atoms, the alkaline-earth atoms, the alkaline-earth ions, the rare gases and some miscellaneous atoms. These effective distributions are used to compute the dipole, quadrupole and octupole static polarizabilities, and are then applied to the calculation of the dynamic polarizabilities at imaginary frequencies. These polarizabilities can be used to determine the long-range C6, C8 and C10 atom–atom interactions for the dimers formed from any of these atoms and ions, and we present tables covering all of these combinations

  11. Effective oscillator strength distributions of spherically symmetric atoms for calculating polarizabilities and long-range atom–atom interactions

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Jun, E-mail: phyjiang@yeah.net [Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); School of Engineering, Charles Darwin University, Darwin, Northern Territory, 0909 (Australia); Mitroy, J. [School of Engineering, Charles Darwin University, Darwin, Northern Territory, 0909 (Australia); Cheng, Yongjun, E-mail: cyj83mail@gmail.com [School of Engineering, Charles Darwin University, Darwin, Northern Territory, 0909 (Australia); Academy of Fundamental and Interdisciplinary Science, Harbin Institute of Technology, Harbin 150080 (China); Bromley, M.W.J., E-mail: brom@physics.uq.edu.au [School of Mathematics and Physics, The University of Queensland, Brisbane, Queensland 4075 (Australia)

    2015-01-15

    Effective oscillator strength distributions are systematically generated and tabulated for the alkali atoms, the alkaline-earth atoms, the alkaline-earth ions, the rare gases and some miscellaneous atoms. These effective distributions are used to compute the dipole, quadrupole and octupole static polarizabilities, and are then applied to the calculation of the dynamic polarizabilities at imaginary frequencies. These polarizabilities can be used to determine the long-range C{sub 6}, C{sub 8} and C{sub 10} atom–atom interactions for the dimers formed from any of these atoms and ions, and we present tables covering all of these combinations.

  12. Effective oscillator strength distributions of spherically symmetric atoms for calculating polarizabilities and long-range atom-atom interactions

    CERN Document Server

    Jiang, Jun; Cheng, Yongjun; Bromley, M W J

    2014-01-01

    Effective oscillator strength distributions are systematically generated and tabulated for the alkali atoms, the alkaline-earth atoms, the alkaline-earth ions, the rare gases and some miscellaneous atoms. These effective distributions are used to compute the dipole, quadrupole and octupole static polarizabilities, and are then applied to the calculation of the dynamic polarizabilities at imaginary frequencies. These polarizabilities can be used to determine the long-range $C_6$, $C_8$ and $C_{10}$ atom-atom interactions for the dimers formed from any of these atoms and ions, and we present tables covering all of these combinations.

  13. Distribution of Partial Neutron Widths for Nuclei close to a Maximum of the Neutron Strength Function

    OpenAIRE

    WeidenmÜller, H.

    2010-01-01

    For nuclei near a maximum of the neutron strength function, the secular dependence on energy E of s-wave partial neutron widths differs from the canonical form given by the square root of E. We derive the universal form of that dependence and show that it is expected to significantly influence the analysis of neutron resonance data.

  14. Distribution of beta-adrenergic receptors in failing human myocardium. Implications for mechanisms of down-regulation

    International Nuclear Information System (INIS)

    The density of beta-adrenergic receptors is reduced in crude membranes prepared from failing human myocardium. We used quantitative autoradiography of radioligand binding sites in intact tissue slices to determine whether the total tissue content of receptors is reduced and to characterize the transmural distribution of receptors in cardiac myocytes and the coronary vasculature in hearts obtained from nine cardiac transplant patients with severe congestive failure. Binding of [125Iodo]cyanopindolol to transmural slices of human myocardium was rapid, saturable, stereoselective, and displaceable by agonists and antagonists with an appropriate rank order of potency. Binding isotherms in four normal and nine failing ventricles showed a significant reduction in the total tissue content of beta-receptors in failing myocardium (38.3 +/- 2.0 fmol/mg protein) compared with normal tissue (52.4 +/- 1.7 fmol/mg protein, p = 0.038). In the normal ventricles, the greatest receptor density was observed autoradiographically in myocytic regions of the subendocardium. Receptor density of the coronary arterioles was approximately 70% of that in adjacent myocytic regions. The density of binding sites in both myocytic regions and arterioles was diminished in all regions of the failing ventricles, but down-regulation was due primarily to a selective reduction of beta-receptors of subendocardial myocytes (63 +/- 5% of subepicardial receptor density vs. 115 +/- 6% in controls, p less than 0.0001). These observations indicate that down-regulation occurs nonuniformly in the transmural distribution and thus is likely not related simply to elevated circulating catecholamine levels

  15. High-resolution study of the Gamow-Teller strength distribution in the light nuclei 9B and 13N using the (3He,t) charge-exchange reaction at 420 MeV beam energy

    International Nuclear Information System (INIS)

    Excited states in the light nuclei 9B and 13C were studied using the (3He,t) charge-exchange reaction on 9Be and 13C targets. The measurements were performed at the research center for nuclear physics (RCNP) in Osaka, Japan, using the magnetic spectrometer Grand Raiden and the dispersive WS course. The 3He beam with an energy of 420 MeV was accelerated by the RCNP Ring Cyclotron. The Grand Raiden spectrometer and the WS course allow to study the (3He,t) charge-exchange reaction with an energy resolution of around 30 keV, which is one order of magnitude better than measurements with the (p,n) charge-exchange reaction. The high resolution allows to better separate individual states and to determine weak excitation strengths because of low background in the spectra. A total of 19 states in 13N were studied, and a total of 20 states were observed in 9B. Of these, 9 states in 13C and 10 states in 9B were identified as being excited by a Gamow-Teller transition. Charge-exchange reactions are related to beta-decay, and at zero momentum transfer a simple proportionality exists between the cross-section of the charge-exchange experiment and the Fermi (F) or Gamow-Teller (GT) beta-decay strength. While the Fermi strength B(F) is concentrated in the transition to the isobaric analog state, the Gamow-Teller strength B(GT) is scattered among the excited states. The main aim of the present study is to determine the B(GT) strengths in the nuclei 9B and 13N. The only charge-exchange study of 9B was made 30 years ago with the (p,n) reaction and a resolution of around 300-400 keV. Many states, especially at high excitation energy, could not be resolved by that study. The present work was able to separate many weakly excited states with small decay width at high excitation energies (12-19 MeV) in 9B and determine the B(GT) strength distribution by using recent high-precision beta-decay data. The results point to a strong difference in spatial structure between the low-lying levels of

  16. High-resolution study of the Gamow-Teller strength distribution in the light nuclei {sup 9}B and {sup 13}N using the ({sup 3}He,t) charge-exchange reaction at 420 MeV beam energy

    Energy Technology Data Exchange (ETDEWEB)

    Scholl, Clemens

    2010-07-07

    Excited states in the light nuclei {sup 9}B and {sup 13}C were studied using the ({sup 3}He,t) charge-exchange reaction on {sup 9}Be and {sup 13}C targets. The measurements were performed at the research center for nuclear physics (RCNP) in Osaka, Japan, using the magnetic spectrometer Grand Raiden and the dispersive WS course. The {sup 3}He beam with an energy of 420 MeV was accelerated by the RCNP Ring Cyclotron. The Grand Raiden spectrometer and the WS course allow to study the ({sup 3}He,t) charge-exchange reaction with an energy resolution of around 30 keV, which is one order of magnitude better than measurements with the (p,n) charge-exchange reaction. The high resolution allows to better separate individual states and to determine weak excitation strengths because of low background in the spectra. A total of 19 states in {sup 13}N were studied, and a total of 20 states were observed in {sup 9}B. Of these, 9 states in {sup 13}C and 10 states in {sup 9}B were identified as being excited by a Gamow-Teller transition. Charge-exchange reactions are related to beta-decay, and at zero momentum transfer a simple proportionality exists between the cross-section of the charge-exchange experiment and the Fermi (F) or Gamow-Teller (GT) beta-decay strength. While the Fermi strength B(F) is concentrated in the transition to the isobaric analog state, the Gamow-Teller strength B(GT) is scattered among the excited states. The main aim of the present study is to determine the B(GT) strengths in the nuclei {sup 9}B and {sup 13}N. The only charge-exchange study of {sup 9}B was made 30 years ago with the (p,n) reaction and a resolution of around 300-400 keV. Many states, especially at high excitation energy, could not be resolved by that study. The present work was able to separate many weakly excited states with small decay width at high excitation energies (12-19 MeV) in {sup 9}B and determine the B(GT) strength distribution by using recent high-precision beta-decay data. The

  17. Insulin resistance and beta-cell function in different ethnic groups in Kenya: the role of abdominal fat distribution.

    Science.gov (United States)

    Christensen, D L; Faurholt-Jepsen, D; Faerch, K; Mwaniki, D L; Boit, M K; Kilonzo, B; Tetens, I; Friis, H; Borch-Johnsen, K

    2014-02-01

    Little is known about the pathophysiology of diabetes in Africans. Thus, we assessed whether insulin resistance and beta-cell function differed by ethnicity in Kenya and whether differences were modified by abdominal fat distribution. A cross-sectional study in 1,087 rural Luo (n = 361), Kamba (n = 378), and Maasai (n = 348) was conducted. All participants had a standard 75-g oral glucose tolerance test (OGTT). Venous blood samples were collected at 0, 30, and 120 min. Serum insulin was analysed at 0 and 30 min. From the OGTT, we assessed the homoeostasis model assessment of insulin resistance by computer model, early phase insulin secretion, and disposition index (DI) dividing insulin secretion by insulin resistance. Abdominal subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) thickness were carried out by ultrasonography. Linear regression analyses were done to assess ethnic differences in insulin indices. The Maasai had 32 and 17% higher insulin resistance than the Luo and Kamba, respectively (p Maasai compared to the Luo (p Maasai compared to the Luo and Kamba, respectively. Adjustments of SAT (range 0.1-7.1 cm) and VAT (range 1.5-14.2 cm) largely explained these inter-group differences with the Maasai having the highest combined abdominal fat accumulation. The Maasai had the highest insulin resistance and secretion, but the lowest relative beta-cell function compared to the Luo and Kamba. These differences were primarily explained by abdominal fat distribution. PMID:23563691

  18. Non-parametric asymptotic statistics for the Palm mark distribution of \\beta-mixing marked point processes

    CERN Document Server

    Heinrich, Lothar; Schmidt, Volker

    2012-01-01

    We consider spatially homogeneous marked point patterns in an unboundedly expanding convex sampling window. Our main objective is to identify the distribution of the typical mark by constructing an asymptotic \\chi^2-goodness-of-fit test. The corresponding test statistic is based on a natural empirical version of the Palm mark distribution and a smoothed covariance estimator which turns out to be mean-square consistent. Our approach does not require independent marks and allows dependences between the mark field and the point pattern. Instead we impose a suitable \\beta-mixing condition on the underlying stationary marked point process which can be checked for a number of Poisson-based models and, in particular, in the case of geostatistical marking. Our method needs a central limit theorem for \\beta-mixing random fields which is proved by extending Bernstein's blocking technique to non-cubic index sets and seems to be of interest in its own right. By large-scale model-based simulations the performance of our t...

  19. Muscle Strength and Mass Distribution Identification Toward Subject-Specific Musculoskeletal Modeling

    OpenAIRE

    Hayashibe, Mitsuhiro; Venture, Gentiane; Ayusawa, Ko; Nakamura, Yoshihiko

    2011-01-01

    In current biomechanics approach, the assumptions are commonly used in body-segment parameters and muscle strength parameters due to the difficulty in accessing those subject-specific values. Especially in the rehabilitation and sports science where each subject can easily have quite different anthropometry and muscle condition due to disease, age or training history, it would be important to identify those parameters to take benefits correctly from the recent advances in computational muscul...

  20. The effect of oxide particles on the strength and ductility of bulk iron with a bimodal grain size distribution

    Energy Technology Data Exchange (ETDEWEB)

    Casas, C.; Tejedor, R. [Department of Materials Science and Metallurgical Engineering, ETSEIB, Universitat Politècnica de Catalunya, Av. Diagonal 647, 08028 Barcelona (Spain); Rodríguez-baracaldo, R. [Department of Mechanical Engineering, Universidad Nacional de Colombia, Bogotá. Colombia (Colombia); Benito, J.A., E-mail: Josep.a.benito@upc.edu [Department of Materials Science and Metallurgical Engineering, EUETIB, Universitat Politècnica de Catalunya, Comte d' Urgell 187, 08036 Barcelona (Spain); Fundació CTM Centre Tecnològic de Manresa, Plaça de la Ciencia, 2, 08243 Manresa (Spain); Cabrera, J.M. [Department of Materials Science and Metallurgical Engineering, ETSEIB, Universitat Politècnica de Catalunya, Av. Diagonal 647, 08028 Barcelona (Spain); Fundació CTM Centre Tecnològic de Manresa, Plaça de la Ciencia, 2, 08243 Manresa (Spain)

    2015-03-11

    The strength and ductility of bulk nanostructured and ultrafine-grained iron containing 0.39% oxygen by weight was determined by tensile tests. Samples were obtained by consolidation of milled iron powder at 500 °C. Heat treatments were designed to cover a wide range of grain sizes spanning from 100 to 2000 nm with different percentages of coarse and nanostructured grain areas, which was defined as a bimodal grain size distribution. Transmission electron microscopy was used to determine the diameter, volume fraction and location of oxides in the microstructure. The strength was analysed following two approaches. The first one was based on the strong effect of oxides and involved the use of a mixed particle-grain boundary strengthening model, and the second one was based on simple grain boundary strengthening. The mixed model underestimated the strength of nanostructured samples, whereas the simple grain boundary model worked better. However, for specimens with a bimodal grain size, the fitting of the mixed model was better. In this case, the more effective particle strengthening was related to the dispersion of oxides inside the large ferrite grains. In addition, the bimodal samples showed an acceptable combination of strength and ductility. Again, the ferrite grains containing oxides promoted strain hardening due to the increase in dislocation activity.

  1. The effect of oxide particles on the strength and ductility of bulk iron with a bimodal grain size distribution

    International Nuclear Information System (INIS)

    The strength and ductility of bulk nanostructured and ultrafine-grained iron containing 0.39% oxygen by weight was determined by tensile tests. Samples were obtained by consolidation of milled iron powder at 500 °C. Heat treatments were designed to cover a wide range of grain sizes spanning from 100 to 2000 nm with different percentages of coarse and nanostructured grain areas, which was defined as a bimodal grain size distribution. Transmission electron microscopy was used to determine the diameter, volume fraction and location of oxides in the microstructure. The strength was analysed following two approaches. The first one was based on the strong effect of oxides and involved the use of a mixed particle-grain boundary strengthening model, and the second one was based on simple grain boundary strengthening. The mixed model underestimated the strength of nanostructured samples, whereas the simple grain boundary model worked better. However, for specimens with a bimodal grain size, the fitting of the mixed model was better. In this case, the more effective particle strengthening was related to the dispersion of oxides inside the large ferrite grains. In addition, the bimodal samples showed an acceptable combination of strength and ductility. Again, the ferrite grains containing oxides promoted strain hardening due to the increase in dislocation activity

  2. Characterization of fracture and deformation mechanism in a high strength beta titanium alloy Ti-10-2-3 using EBSD technique

    International Nuclear Information System (INIS)

    In the present study, fracture toughness tested specimens in longitudinal (LT) and transverse loading (TL) directions of beta titanium alloy have been investigated using Electron Back Scattered Diffraction (EBSD) technique. The orientation images captured at three different locations i.e. machine notch, fatigue pre-crack and final fracture have been compared. The LT sample exhibits with more facets than TL sample. The faceted aspect of the crack is generally associated with quasi-cleavage mechanism. The EBSD analysis clearly points out that in the LT specimen, the hexagonal orientation has moved towards near basal during the test. This may be the reason for the observance of facets in the LT specimen. The cracking in TL specimen might have been taken over by the bcc phase as it is oriented with harder planes of cubic {001} planes. Further, the Schmid factor has also been computed based on the defined loading conditions. Significant variation has been observed in the slip plane orientations and distributions at these three locations. The Schmid analysis has highlighted the significant contribution of different slip systems towards deformation and cracking in LT and TL specimens

  3. Effects of 17beta-estradiol on distribution of primordial germ cell migration in male chicks

    Institute of Scientific and Technical Information of China (English)

    Xiu-Mei Jin; Yi-Xiang Zhang; Zan-Dong Li

    2008-01-01

    Aim: To assess whether exogenous estradiol has any effect on migration of primordial germ cells (PGCs) in the chick. Methods: Fertilized eggs were treated with 17beta-estradiol (Ez) (80 lag/egg) at stage X (day 0 of incubation),stages 8-10 (incubation 30 h) and 13-15 (incubation 55 h). Controls received vehicle (emulsion) only. Changes in PGC number were measured on different days according to developmental stages. Results: In male right gonads,but not in female left gonads, at stages 28-30 (incubation 132 h) significant decreases in the mean number of PGCs aggregating were observed compared with the controls (P 0.05). Conclusion: The present study provides evidence that E2 has significant effects on the localization of PGCs in male fight, but not female left, gonads of chicken embryos at stages28-30, compared with controls.

  4. Permeability and pore size distribution in medium strength self-compacting concrete

    Directory of Open Access Journals (Sweden)

    Fernández Cánovas, M.

    2010-09-01

    Full Text Available The use of self-compacting concrete (SCC has been on the rise in recent years. Research on this type of concrete has focused primarily on determining optimal dosage, while durability, particularly for medium strength SCC, has received much less attention. The present study explored the permeability of a number of medium strength (characteristic strength, 30 MPa self-compacting concretes, including SCCs made with common cement, in pursuit of a balance between performance and cost. Pressurised water and mercury intrusion porosimetry tests were conducted to determine concrete behaviour when exposed to aggressive agents. The findings showed that the capillary networks of these concretes are essentially impermeable to aggressive agents.

    El hormigón autocompactante ha experimentado un amplio desarrollo en los últimos años. Los estudios sobre este hormigón se han centrado en obtener dosificaciones óptimas, mientras los relativos a su durabilidad son escasos, especialmente en el caso de hormigones de resistencia moderada. Este trabajo se centra en el estudio de la permeabilidad de distintos hormigones autocompactantes de resistencia moderada (resistencia característica 30 MPa. El estudio incluye hormigones fabricados con cementos comunes, en los que se ha buscado un equilibrio entre prestaciones y precio. Con el fin de estudiar su comportamiento frente a la penetración de agentes agresivos, se han realizado los ensayos de permeabilidad al agua bajo presión y estudio de la porosimetría por intrusión de mercurio. Los resultados de los ensayos ponen de manifiesto el buen comportamiento de estos hormigones frente a la posible penetración de agentes agresivos por la red capilar.

  5. ON ESTIMATION OF STRESS STRENGTH MODEL FOR GENERALIZED INVERTED EXPONENTIAL DISTRIBUTION

    Directory of Open Access Journals (Sweden)

    Mohamed A. Hussian

    2013-12-01

    Full Text Available his paper, the estimation of R =Pr(Y < Y, when X and Y are two generalized inverted exponential distributions with different p arameters is considered. The maximum likelihood estimator (MLE of R and its asymptotic distribution are obtained. Exac t and asymptotic confidence intervals of R are constructed using both exact and asymptotic distributions. Assuming that the common scale param eter is known, MLE, Bayes estimators and confidence intervals of R are investigated. Bayes estimators are based on inf ormative and non- informative priors of the unknown parameters. Monte Carlo simulations are performed to compare and to validate the different proposed esti mators.

  6. Oscillator-strength distributions for oxygen, carbon dioxide, water, methyl chloride, and carbon tetrachloride

    International Nuclear Information System (INIS)

    New measurements of photoabsorption give oscillator-strength values for the following gases and energy regions: O2, 7.34 to 11.79 eV; CO2, 7.34 to 11.77 eV; H2O, 6.62 to 11.80 eV; CH3CL, 6.14 to 11.25 eV; and CCl4, 6.14 to 11.49 eV. Comparisons are made with some values from the literature

  7. Effects of uneven moisture distribution on the strength of and wave velocity in concrete.

    Science.gov (United States)

    Popovics, Sandor

    2005-05-01

    Earlier findings showed that the effects of moisture (liquid or free water) in hardened concrete on its behavior, especially the lesser known effects ofuneven moisture distribution, can (a) be significant, and (b) vary from property to property. This distribution, for instance whether or not the surface layer is drier than the overall average moisture content, can be characterized by the difference between the velocity of the longitudinal wave (pulse velocity) measured in the standard through-thickness manner, and the velocity of the longitudinal wave propagating on the concrete surface. The summary of earlier findings on the effects of moisture distribution is followed by a recent investigation on pulse velocity in the special case, occurring frequently in practice, when the distribution is uneven because the liquid is concentrated in cracks in the concrete. PMID:15823317

  8. Beta delayed alpha emission from the neutron deficient rare earth isotopes 152Tm and 150Ho

    International Nuclear Information System (INIS)

    The study of beta-delayed proton emission is a well known method to aid the determination of the beta strength distribution in nuclei far from the stability line. At the neutron deficient side of the nuclear chart the process of proton or alpha emission from excited states is energetically allowed when one goes far enough from stability. However, beta-delayed alphas have seldom been measured for nuclei heavier than A = 20. Here we present a study of the beta-delayed alpha-particle emission from 152Tm and 150Ho and their importance in the full B(GT) distribution.

  9. Calculation of beta-ray dose distributions from ophthalmic applicators and comparison with measurements in a model eye

    International Nuclear Information System (INIS)

    Dose distributions throughout the eye, from three types of beta-ray ophthalmic applicators, were calculated using the EGS4, ACCEPT 3.0, and other Monte Carlo codes. The applicators were those for which doses were measured in a recent international intercomparison [Med. Phys. 28, 1373 (2001)], planar applicators of 106Ru-106Rh and 90Sr-90Y and a concave 106Ru-106Rh applicator. The main purpose was to compare the results of the various codes with average experimental values. For the planar applicators, calculated and measured doses on the source axis agreed within the experimental errors (106Ru-106Rh and 5 mm for 90Sr-90Y. At greater distances the measured values are larger than those calculated. For the concave 106Ru-106Rh applicator, there was poor agreement among available calculations and only those calculated by ACCEPT 3.0 agreed with measured values. In the past, attempts have been made to derive such dose distributions simply, by integrating the appropriate point-source dose function over the source. Here, we investigated the accuracy of this procedure for encapsulated sources, by comparing such results with values calculated by Monte Carlo. An attempt was made to allow for the effects of the silver source window but no corrections were made for scattering from the source backing. In these circumstances, at 6 mm depth, the difference in the results of the two calculations was 14%-18% for a planar 106Ru-106Rh applicator and up to 30% for the concave applicator. It becomes worse at greater depths. These errors are probably caused mainly by differences between the spectrum of beta particles transmitted by the silver window and those transmitted by a thickness of water having the same attenuation properties

  10. Hydroxyalkylation of phenol to bisphenol F over heteropolyacid catalysts: The effect of catalyst acid strength on isomer distribution and kinetics.

    Science.gov (United States)

    Wu, Xianzhang; Liu, Yutang; Liu, Ran; Wang, Longlu; Lu, Yanbing; Xia, Xinnian

    2016-11-01

    Hydroxyalkylation of phenol with formaldehyde to bisphenol F over heteropolyacid impregnated on clay was investigated. These catalysts displayed excellent catalytic performance for this reaction, especially that the effects of acid sites on the isomer distribution are obvious. Various solid catalysts were prepared by impregnating heteropolyacid on different kind of clay matrices, and their chemical compositions, textural properties, and acid strength of the heteropolyacid catalysts were characterized by EDX, BET, NH3-TPD, XRD, and FT-IR. Moreover, the effects of acid sites and reaction temperature on the yield and 4,4'-isomer distribution were launched by comparing the data obtained from the two kinds of catalysts. Furthermore, the kinetics of the hydroxyalkylation of phenol to BPF was established. PMID:27451037

  11. Study of the strength distribution of primary γ-transitions in the decay from superdeformed states in 194Hg

    International Nuclear Information System (INIS)

    The strength distribution of the primary γ rays in the decay from superdeformed (SD) states is investigated by applying the maximum likelihood method. For the 194Hg nucleus, 41 primary transitions are identified above 2600 keV. It is concluded that they represent the strongest 10% of the transitions selected stochastically from a Porter-Thomas distribution. This would support the scenario of a statistical decay of SD states via coupling to a compound state at normal deformation. However, the occurrence of several very strong 'one-step linking' transitions is found to have a very small probability. Based on the absence of strong primary transitions from SD states in adjacent nuclei, the situation in 194Hg is viewed as a very lucky incidence

  12. On the theories of angular distribution and correlation of beta and gamma radiation

    NARCIS (Netherlands)

    Groot, S.R. de

    1952-01-01

    In both phenomena of angular distribution and angular correlation, one has nuclear radiation from ensembles of nuclei with an unequal population of the magnetic sub-levels. This population is described by appropriate “orientation parameters”. On this basis the theories of the directional as well as

  13. Mixed and Mixture Regression Models for Continuous Bounded Responses Using the Beta Distribution

    Science.gov (United States)

    Verkuilen, Jay; Smithson, Michael

    2012-01-01

    Doubly bounded continuous data are common in the social and behavioral sciences. Examples include judged probabilities, confidence ratings, derived proportions such as percent time on task, and bounded scale scores. Dependent variables of this kind are often difficult to analyze using normal theory models because their distributions may be quite…

  14. A prediction scheme of the static fracture strength of MEMS structures based on the characterization of damage distribution on a processed surface

    International Nuclear Information System (INIS)

    This paper presents a scheme for predicting the strength of MEMS structures patterned into arbitrary shapes by deep reactive ion etching of a silicon wafer. The scheme is based on the inhomogeneous defect distribution on the etched surfaces. Single-crystal silicon specimens with different shapes were subjected to four-point bending tests with monotonically increasing load. The distributions of the fracture strength were described using two-parameter Weibull statistics, where the two parameters are defined as functions of the etching depth representing the inhomogeneity of the damage on the etched surface in the direction perpendicular to the wafer. In order to estimate the distribution of the local strength determined by the local level of damage, the etched surfaces of specimens without a notch were tested in three different bending directions corresponding to three different stress distributions, and three different strength levels were given due to surface roughness conditions caused by the non-uniformity of the etching process. The estimated values of the parameters were used to estimate the fracture strength of four types of notched specimens with different notch tip radii. The results of comparison between the distributions of predicted strengths and experimental data showed that the fracture strength of arbitrarily shaped structures is predictable on the basis of the information obtained from specimens without notch, by taking into account the characteristics of etched surface, i.e. the inhomogeneous damage. (paper)

  15. Dipole-strength distributions below the giant dipole resonance in 92Mo, 98Mo and 100Mo

    International Nuclear Information System (INIS)

    Investigations of the dipole-strength distributions in 92Mo, 98Mo and 100Mo were carried out by means of the method of nuclear resonance fluorescence. The low-lying excitations in the nuclides 92Mo, 98Mo and 100Mo have been studied in photon-scattering experiments at an electron energy of 6 MeV at the ELBE accelerator and at electron energies from 3.2 to 3.8 MeV at the Dynamitron accelerator. Five levels were observed in 92Mo. Five levels in 98Mo and 14 in 100Mo were identified for the first time in the energy range from 2 to 4 MeV. Dipole-strength distributions up to the neutron-separation energies in the nuclides 92Mo, 98Mo and 100Mo have been investigated at the ELBE accelerator. Because of the possible observation of transitions in the neighboring nuclei produced via (γ,n) reaction, additional measurements at electron energies of 8.4 and 7.8 MeV, below the neutron-separation energy, were performed on 98Mo and 100Mo, respectively. The number of transitions assigned to 92Mo, 98Mo and 100Mo is 340, 485 and 499, respectively, the main part of them being dipole transitions. Statistical properties of the observed transitions are obtained. The continuum contains the ground-state transitions as well as the branching transitions to the low-lying levels and the subsequent deexcitations of these levels. (orig.)

  16. Fracture strength and stress distributions of pulpless premolars restored with fiber posts.

    Science.gov (United States)

    Furuya, Yu; Huang, Shih-Hao; Takeda, Yuko; Fok, Alex; Hayashi, Mikako

    2014-01-01

    This study examined the effect of glass fiber posts on increasing the fracture resistance of endodontically treated teeth. Extracted upper premolars with two canals in a root were divided into three groups according to the number of posts they were restored with: none, one, or two. All teeth were endodontically treated, crown-sectioned, and restored with a composite core and a metallic crown. A static oblique load was applied to the restored tooth until fracture, and the fracture pattern was recorded. Stress distributions were examined by finite element analysis (FEA). Teeth with glass fiber post(s) showed significantly higher fracture loads compared with those without posts. In the premolars without posts, von Mises and maximum principal stresses were found on the root surface alone; in premolars restored with posts, stresses were distributed on both root and post surfaces. Risk of root dentin fracture was significantly lowest in teeth restored with two posts. PMID:25483385

  17. Neutron diffraction analysis of residual strain/stress distribution in the vicinity of high strength welds

    OpenAIRE

    Hamák I.; Karlsson L.; Mráz L.; Vrána M.; Mikula P.

    2010-01-01

    Residual stresses resulting from non homogeneous heat distribution during welding process belong to most significant factor influencing behavior of welded structures. These stresses are responsible for defect occurrence during welding and they are also responsible for crack initiation and propagation at the either static or dynamic load. The significant effect of weld metal chemical composition as well as the effect of fatigue load and local plastic deformation on residual stress distri...

  18. Spatial scale modulates the strength of ecological processes driving disease distributions.

    Science.gov (United States)

    Cohen, Jeremy M; Civitello, David J; Brace, Amber J; Feichtinger, Erin M; Ortega, C Nicole; Richardson, Jason C; Sauer, Erin L; Liu, Xuan; Rohr, Jason R

    2016-06-14

    Humans are altering the distribution of species by changing the climate and disrupting biotic interactions and dispersal. A fundamental hypothesis in spatial ecology suggests that these effects are scale dependent; biotic interactions should shape distributions at local scales, whereas climate should dominate at regional scales. If so, common single-scale analyses might misestimate the impacts of anthropogenic modifications on biodiversity and the environment. However, large-scale datasets necessary to test these hypotheses have not been available until recently. Here we conduct a cross-continental, cross-scale (almost five orders of magnitude) analysis of the influence of biotic and abiotic processes and human population density on the distribution of three emerging pathogens: the amphibian chytrid fungus implicated in worldwide amphibian declines and West Nile virus and the bacterium that causes Lyme disease (Borrelia burgdorferi), which are responsible for ongoing human health crises. In all three systems, we show that biotic factors were significant predictors of pathogen distributions in multiple regression models only at local scales (∼10(2)-10(3) km(2)), whereas climate and human population density always were significant only at relatively larger, regional scales (usually >10(4) km(2)). Spatial autocorrelation analyses revealed that biotic factors were more variable at smaller scales, whereas climatic factors were more variable at larger scales, as is consistent with the prediction that factors should be important at the scales at which they vary the most. Finally, no single scale could detect the importance of all three categories of processes. These results highlight that common single-scale analyses can misrepresent the true impact of anthropogenic modifications on biodiversity and the environment. PMID:27247398

  19. Embedded NMR Sensor to Monitor Compressive Strength Development and Pore Size Distribution in Hydrating Concrete

    Directory of Open Access Journals (Sweden)

    Floriberto Díaz-Díaz

    2013-11-01

    Full Text Available In cement-based materials porosity plays an important role in determining their mechanical and transport properties. This paper describes an improved low–cost embeddable miniature NMR sensor capable of non-destructively measuring evaporable water loss and porosity refinement in low and high water-to-cement ratio cement-based materials. The sensor consists of two NdFeB magnets having their North and South poles facing each other, separated by 7 mm to allow space for a Faraday cage containing a Teflon tube and an ellipsoidal RF coil. To account for magnetic field changes due to temperature variations, and/or the presence of steel rebars, or frequency variation due to sample impedance, an external tuning circuit was employed. The sensor performance was evaluated by analyzing the transverse magnetization decay obtained with a CPMG measurement from different materials, such as a polymer phantom, fresh white and grey cement pastes with different w/c ratios and concrete with low (0.30 and high (0.6 w/c ratios. The results indicated that the sensor is capable of detecting changes in water content in fresh cement pastes and porosity refinement caused by cement hydration in hardened materials, even if they are prepared with a low w/c ratio (w/c = 0.30. The short lifetime component of the transverse relaxation rate is directly proportional to the compressive strength of concrete determined by destructive testing. The r2 (0.97 from the linear relationship observed is similar to that obtained using T2 data from a commercial Oxford Instruments 12.9 MHz spectrometer.

  20. Regional and ethnic distribution of beta thalassemia mutations and effect of consanguinity in patients referred for prenatal diagnosis

    International Nuclear Information System (INIS)

    To determine the regional and ethnic distribution of beta thalassemia mutation and the effect of consanguinity in patients referred for prenatal diagnosis of beta b-thalassemia and to target the high risk population for screening. A total of 499 couples were referred to Gentec Lab., Lahore, from all over Pakistan for prenatal diagnosis of b-thalassemia. After counseling, chorionic villus sampling was done between 10-16 weeks of gestation. DNA analysis was done by Amplification Refractory Mutation System (ARMS) for type of mutation in the Armed Forces Institute of Pathology, Rawalpindi. Ethnicity, race and consanguineous relationship of parents was determined.b-thalassemia was prevalent in Punjabis (60.7%) followed by Saraikees (25.5%). Castewise it was most frequent in Rajputs followed by Jatts, Arain, Sheikhs and Pathans. 56.7% of the couples were first cousins and 19.8% were relatives. The commonest mutations were Frameshift 8-9 (Fr8-9) 33.5%, Intervening Sequence 1-5 (IVS 1-5) 17.2%, Fr4142 - 8%, IVS 1-1 - 5.2%, Deletion 619 (Del 619) 4.2% and Codon 5 (Cd 5) - 4.2%. In samples sent for analysis, 53.1% turned out to be carriers (trait), 25.3% were diseased (thalassemia major) and 21.6% were normal. P-value of all results was less than 0.001. In this series, the highest frequency was found in Punjabi Rajputs. The commonest mutation was Fr 8-9. Most parents were first cousins. Premarital thalassemia carrier testing can effectively reduce the disease. (author)

  1. Co-beta Zeolite Highly Active in Propane-SCR-NOx in the Presence of Water Vapor: Effect of Zeolite Preparation and Al Distribution in the Framework

    Czech Academy of Sciences Publication Activity Database

    Čapek, Libor; Dědeček, Jiří; Wichterlová, Blanka

    2004-01-01

    Roč. 227, č. 2 (2004), s. 352-366. ISSN 0021-9517 R&D Projects: GA MŠk 1P04OCD15.20 Institutional research plan: CEZ:AV0Z4040901 Keywords : Co-beta * SCR -NOx * Al distribution in zeolites Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 4.063, year: 2004

  2. Strength evaluation of a steam distribution device in the Ignalina NPP accident localisation system

    International Nuclear Information System (INIS)

    The Ignalina NPP has a pressure suppression type of confinement, which is referred to as the accident localization system (ALS). The ALS prevents the release of the radioactive material from the NPP to the environment during a loss-of-coolant accident (LOCA). Ten water pools are located in the two ALS towers (five pools in each tower), which separate the dry well from the wet well. These water pools condense the accident-generated steam and prevent high overpressures in the compartments. The steam distribution device (SDD), with the vertical vent pipes (nozzles) that are inserted under the water of the condensing pools, connects the dry well and the wet well. In case of an accident, these components must be capable of withstanding the dynamic loads generated by a LOCA for successful pressure suppression function. This paper presents the transient analysis of the SDD and their connections to the vertical steam corridors following a LOCA. A thermo-hydraulic analysis of the SDD was performed using the state-of-the-art COCOSYS code to determine pressure and temperature histories resulting from a LOCA. The finite element code NEPTUNE was used to evaluate the structural integrity of the SDD and its supporting reinforced concrete wall. Results show that, although portions of the SDD undergo plastic response and the outside surface of the vertical steam corridor reinforced concrete wall cracks, the structural integrity of the SDD and wall are maintained during a LOCA

  3. Compressive Strength, Pore Size Distribution and Chloride-ion Penetration of Recycled Aggregate Concrete Incorporating Class-F Fly Ash

    Institute of Scientific and Technical Information of China (English)

    KOU Shicong; C S Poon

    2006-01-01

    The effects of fly ash on the compressive strength, pore size distribution ard chloride-ion penetration of recycled aggregate concrete were investigated. Two series of concrete mixtures were prepared. The concrete mixtures in series I had a water-to-binder ratio and a cement content of 0.55 and 410 kg/m3 , respectively. The concrete mixtures in series Ⅱ had a water-to-binder ratio and a cement content of 0.45 and 400 kg/m3 respectively. Recycled aggregate was used as 20% , 50% , and 100% replacements of natural coarse aggregate in the concrete mixtures in both series. In addition, fly ash was used as 0% , 25% and 35% by weight replacements of cement. The results show that the compressive strengths of the concrete decreased as the recycled aggregate and the fly ash contents increased. The total porosity and average porosity diameter of the concrete increased as the recycled aggregate content increased. Furthermore, an increase in the recycled aggregate content decreased the resistance to chloride ion penetration. Nevertheless, the replacement of cement by 25% fly ash improved the resistance to chloride ion penetration and pore diameters and reduced the total porosity of the recycled aggregate concrete.

  4. Estimation of distribution coefficient of natural radionuclides in soil around uranium mines and its effect with ionic strength of water.

    Science.gov (United States)

    Mishra, S; Maity, S; Pandit, G G

    2012-11-01

    The distribution coefficient, K(d) in soil is an important parameter to predict the migration of contaminants. In this study, uranium (U) and its decay products thorium (Th), radium (Ra), bismuth (Bi), lead (Pb) and polonium (Po), which may contaminate the soil and ground water around uranium mining areas, have been considered. Soil and ground water samples were collected from a proposed uranium mining site in India. The soil samples were characterised for different parameters affecting the K(d) values. The batch sorption method was employed to measure the K(d) of different radionuclides. The important factors affecting the batch method for K(d) estimation were identified and optimised. The variation of K(d) was observed with different ionic strength water samples. Results showed high K(d) values for Th(IV), Po(IV) and Pb(II) (log K(d) ∼4) and low K(d) (log K(d) ∼2-3) for U(VI), Ra(II) and Bi(III) in all three types of water with different ionic strength. PMID:22927651

  5. Estimation of distribution coefficient of natural radionuclides in soil around uranium mines and its effect with ionic strength of water

    International Nuclear Information System (INIS)

    The distribution coefficient, Kd in soil is an important parameter to predict the migration of contaminants. In this study, uranium (U) and its decay products thorium (Th), radium (Ra), bismuth (Bi), lead (Pb) and polonium (Po), which may contaminate the soil and ground water around uranium mining areas, have been considered. Soil and ground water samples were collected from a proposed uranium mining site in India. The soil samples were characterised for different parameters affecting the Kd values. The batch sorption method was employed to measure the Kd of different radionuclides. The important factors affecting the batch method for Kd estimation were identified and optimised. The variation of Kd was observed with different ionic strength water samples. Results showed high Kd values for Th(IV), Po(IV) and Pb(II) (log Kd ∼4) and low Kd (log Kd ∼2-3) for U(VI), Ra(II) and Bi(III) in all three types of water with different ionic strength. (authors)

  6. BETA-S, Multi-Group Beta-Ray Spectra

    International Nuclear Information System (INIS)

    1 - Description of program or function: BETA-S calculates beta-decay source terms and energy spectra in multigroup format for time-dependent radionuclide inventories of actinides, fission products, and activation products. Multigroup spectra may be calculated in any arbitrary energy-group structure. The code also calculates the total beta energy release rate from the sum of the average beta-ray energies as determined from the spectral distributions. BETA-S also provides users with an option to determine principal beta-decaying radionuclides contributing to each energy group. The CCC-545/SCALE 4.3 (or SCALE4.2) code system must be installed on the computer before installing BETA-S, which requires the SCALE subroutine library and nuclide-inventory generation from the ORIGEN-S code. 2 - Methods:Well-established models for beta-energy distributions are used to explicitly represent allowed, and 1., 2. - and 3. -forbidden transition types. Forbidden non-unique transitions are assumed to have a spectral shape of allowed transitions. The multigroup energy spectra are calculated by numerically integrating the energy distribution functions using an adaptive Simpson's Rule algorithm. Nuclide inventories are obtained from a binary interface produced by the ORIGEN-S code. BETA-S calculates the spectra for all isotopes on the binary interface that have associated beta-decay transition data in the ENSDF-95 library, developed for the BETA-S code. This library was generated from ENSDF data and contains 715 materials, representing approximately 8500 individual beta transition branches. 3 - Restrictions on the complexity of the problem: The algorithms do not treat positron decay transitions or internal conversion electrons. The neglect of positron transitions in inconsequential for most applications involving aggregate fission products, since most of the decay modes are via electrons. The neglect of internal conversion electrons may impact on the accuracy of the spectrum in the low

  7. Gamow-Teller strength distributions and neutrino energy loss rates due to chromium isotopes in stellar matter

    Science.gov (United States)

    Nabi, Jameel-Un; Shehzadi, Ramoona; Fayaz, Muhammad

    2016-03-01

    Gamow-Teller transitions in isotopes of chromium play a consequential role in the presupernova evolution of massive stars. β-decay and electron capture rates on chromium isotopes significantly affect the time rate of change of lepton fraction (dot{Ye}). Fine-tuning of this parameter is one of the key for simulating a successful supernova explosion. The (anti)neutrinos produced as a result of electron capture and β-decay are transparent to stellar matter during presupernova phases. They carry away energy and this result in cooling the stellar core. In this paper we present the calculations of Gamow-Teller strength distributions and (anti)neutrino energy loss rates due to weak interactions on chromium isotopes of astrophysical importance. We compare our results with measured data and previous calculations wherever available.

  8. Molecular mass distribution and epitopes of the beta lactoglobulin submitted to hydrolysis pre-transglutaminase treatment

    International Nuclear Information System (INIS)

    Full text: The β-Lactoglobulin (β-Lg) is a whey protein with important nutritional proper ties but very resistant to pepsin digestion and consequently highly antigenic. This protein can be modified by transglutaminase (TG) although it is required a pretreatment to increase their susceptibility to the TG action. In the present study the hydrolysis pre-TG treatment was used to improve the TG accessibility on β-Lg and the MM distribution and antigenic fragments were evaluated. For pre-TG treatment, the β-Lg (Davisco Inc.) was hydrolyzed with bromelain (3% of β-Lg w/w in distilled water; 25 U enzyme g1 of substrate, pH 7.5, 240 min) and then polymerized by TG (7% hydrolysate, 10U TG g1 protein, 50 C/180 min). The samples were evaluated by SDS-PAGE/tricine and by RP-nanoUPLC (nanoAcquity UPLC, Waters) coupled with nano-electrospray tandem mass spectrometry on a Q-Tof Ultima API mass spectrometer (MicroMass/Waters) at LNBio. The products were also submitted to pepsin digestion and the peptide identification was performed by RP-HPLC-tandem mass spectrometry (RP-HPLC-MS/MS, Brucker) with support from CIAL. The β-Lg hydrolysed by bromelain and polymerized by TG had a broad MM distribution. The intact mass analysis indicated that the non modified βLg -A showed 18.362 Da and the non modified βLg -B 18.274 Da, which is in agreement with the theoretical corresponding masses. The use of bromelain pre-TG treatment resulted in polymers with MM from 61.052 to 67.654 Da, although some non modified protein was still present. In addition, the non modified β-Lg showed fragments that present high antigenicity (such as Leu95 - Leu104, Asp95 - Phe105, Tyr42 - Leu54, lle29 - Val41), previously identified as IgE-binding epitopes. After hydrolysis following by TG treatment the fragment Tyr42 - Leu54 was still present, however the other fragments that were observed in the non modified β-Lg were not detected by LC-MS/MS, suggesting that structural change occurred in the protein after

  9. Dipole strength distribution below the giant dipole resonance in {sup 92}Mo, {sup 98}Mo and {sup 100}Mo

    Energy Technology Data Exchange (ETDEWEB)

    Rusev, G.Y.

    2006-07-01

    Investigations of the dipole-strength distributions in {sup 92}Mo, {sup 98}Mo and {sup 100}Mo were carried out by means of the method of nuclear resonance fluorescence. The low-lying excitations in the nuclides {sup 92}Mo, {sup 98}Mo and {sup 100}Mo have been studied in photon-scattering experiments at an electron energy of 6 MeV at the ELBE accelerator and at electron energies from 3.2 to 3.8 MeV at the Dynamitron accelerator. Five levels were observed in {sup 92}Mo. Five levels in {sup 98}Mo and 14 in {sup 100}Mo were identified for the first time in the energy range from 2 to 4 MeV. Dipole-strength distributions up to the neutron-separation energies in the nuclides {sup 92}Mo, {sup 98}Mo and {sup 100}Mo have been investigated at the ELBE accelerator. Because of the possible observation of transitions in the neighboring nuclei produced via ({gamma},n) reaction, additional measurements at electron energies of 8.4 and 7.8 MeV, below the neutron-separation energy, were performed on {sup 98}Mo and {sup 100}Mo, respectively. The number of transitions assigned to {sup 92}Mo, {sup 98}Mo and {sup 100}Mo is 340, 485 and 499, respectively, the main part of them being dipole transitions. Statistical properties of the observed transitions are obtained. The continuum contains the ground-state transitions as well as the branching transitions to the low-lying levels and the subsequent deexcitations of these levels. (orig.)

  10. Distributions of chlorophyll a and carbon fixed strength of phytoplankton in autumn of the southern Huanghai Sea waters

    Institute of Scientific and Technical Information of China (English)

    ZHENG Guoxia; SONG Jinming; DAI Jicui; WANG Yiming

    2006-01-01

    Chlorophyll a (Chl a) concentration and primary productivity (PP), namely, carbon fixed strength of phytoplankton along four transects in the southern Huanghai Sea (SHS) were studied for their distribution features and controlling mechanisms based on the investigations from 17 October to 3 November 2005. The Chl a concentration in the study waters dynamically changed spatially.Surface Chl a concentrations ranged from 0.11 to 2.38 mg/m3 with higher and lower values observed in the nutrient-laden inshore waters and central part of the SHS occupied by oligotrophic current, respectively. The vertical distribution of Chl a concentration showed a predominant pattern of subsurface concentration maximum profile. It followed the previous result of the deep dissolved oxygen concentration maximum profile, which was significantly correlated with phytoplankton and regional water mass. The primapecially phosphate concentration in seawater and hydrological condition. Furthermore, associating the present study results together with previous studies, the annual value of carbon fixed production of phytoplankton in the entire marginal seas of East China(including the Bohai Sea, the Huanghai Sea and the East China Sea) was estimated to be 222 Mt, which accounted for 2% of that in the global margins. Besides, it was as 16.2 times as the annual value of apparent carbon sink strength ( 13.96 Mt) in the marginal seas of East China. This multiple was different in different sea areas (3.0 in the Bohai Sea, 6.7 in the Huanghai Sea and 81.6 in the East China Sea).

  11. Distribution of beta-globin haplotypes among the tribes of southern Gujarat, India.

    Science.gov (United States)

    Aggarwal, Aastha; Khurana, Priyanka; Mitra, Siuli; Raicha, Bhavesh; Saraswathy, K N; Italia, Yazdi M; Kshatriya, Gautam K

    2013-06-01

    The present study was carried out in Indo-European speaking tribal population groups of southern Gujarat (India) to elucidate the allelic and haplotypic content of β-globin system in individuals with HbAA genotypes. 6 neutral restriction sites of the β-globin system were analysed and various statistical parameters were estimated to draw meaningful interpretations. All the 6 sites were found to be polymorphic and most were in Hardy-Weinberg Equilibrium in the studied group. Haplotypes were constructed using two different combinations of the 6 restriction sites analysed. Analysis of the 5 sites revealed a set of three predominant haplotypes, '+----', '-++-+' and '-+-++'; and haplotypes '+--', '++-' and '+++' were found to be the most frequent when the 3 sites were used to construct the haplotypes. Haplotypic heterozygosity levels (>83%) observed in the present study group were comparable to those observed in African and Afro-American populations and greater than other world populations. All the ancestral haplotypes, +-----, -++-+, -+-++ and ----+ were found in the study group. The distribution pattern of various haplotypes was consistent with the global pattern. The paucity of comparable data from other Indian populations restricted one from making interpretations about the study group's relationships with other Indian populations but the results were indicative of older population histories or experience of gene flow by the study group and their affinities with populations of southern India. PMID:23500448

  12. Radiation synthesis of gelatin/CM-chitosan/{beta}-tricalcium phosphate composite scaffold for bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Ying [College of Engineering, Peking University, Beijing 100871 (China); Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); Xu Ling, E-mail: lingxu@pku.edu.cn [College of Engineering, Peking University, Beijing 100871 (China); Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); Zhang Xiangmei; Zhao Yinghui [Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); Wei Shicheng, E-mail: sc-wei@pku.edu.cn [Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); Department of Oral and Maxillofacial Surgery, School and Hospital of Stomatology, Peking University, Beijing 100081 (China); Zhai Maolin [Beijing National Laboratory for Molecular Sciences, Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China)

    2012-05-01

    A series of biodegradable composite scaffolds was fabricated from an aqueous solution of gelatin, carboxymethyl chitosan (CM-chitosan) and {beta}-tricalcium phosphate ({beta}-TCP) by radiation-induced crosslinking at ambient temperature. Ultrasonic treatment on the polymer solutions significantly influenced the distribution of {beta}-TCP particles. An ultrasonic time of 20 min, followed by 30 kGy irradiation induced a crosslinked scaffold with homogeneous distribution of {beta}-TCP particles, interconnected porous structure, sound swelling capacity and mechanical strength. Fourier Transform Infrared Spectroscopy and X-ray Diffraction analysis indicated that {beta}-TCP successfully incorporated with the network of gelatin and CM-chitosan. In vivo implantation of the scaffold into the mandible of beagle dog revealed that the scaffolds had excellent biocompatibility and the presence of {beta}-TCP can accelerate bone regeneration. The comprehensive results of this study paved way for the application of gelatin/CM-chitosan/{beta}-TCP composite scaffolds as candidate of bone tissue engineering material. - Highlights: Black-Right-Pointing-Pointer Radiation induced a crosslinked scaffold with interconnected porous structure. Black-Right-Pointing-Pointer Ultrasonic time of 20 min led to homogenerously distribution of {beta}-TCP. Black-Right-Pointing-Pointer Increasing amount of {beta}-TCP would restrict the swelling properties. Black-Right-Pointing-Pointer Proper fraction of {beta}-TCP will promote the mechanical properties of the scaffolds. Black-Right-Pointing-Pointer Hybrid of {beta}-TCP promoted the bone regeneration of the mandibles of beagle dogs.

  13. Phylogenetic sequence analysis, recombinant expression, and tissue distribution of a channel catfish estrogen receptor beta

    Science.gov (United States)

    Xia, Zhenfang; Gale, William L.; Chang, Xiaotian; Langenau, David; Patino, Reynaldo; Maule, Alec G.; Densmore, Llewellyn D.

    2000-01-01

    An estrogen receptor β (ERβ) cDNA fragment was amplified by RT-PCR of total RNAextracted from liver and ovary of immature channel catfish. This cDNA fragment was used to screen an ovarian cDNA library made from an immature female fish. A clone was obtained that contained an open reading frame encoding a 575-amino-acid protein with a deduced molecular weight of 63.9 kDa. Maximum parsimony and Neighbor Joining analyses were used to generate a phylogenetic classification of channel catfish ERβ on the basis of 25 full-length teleost and tetrapod ER sequences. The consensus tree obtained indicated the existence of two major vertebrate ER subtypes, α and β. Within each subtype, and in accordance with established phylogenetic relationships, teleost and tetrapod ER were monophyletic confirming the results of a previous analysis (Z. Xiaet al., 1999, Gen. Comp. Endocrinol. 113, 360–368). Extracts of COS-7 cells transfectedwith channel catfish ERβ cDNA bound estrogen with high affinity (Kd = 0.21 nM) and specificity. The affinity of channel catfish ERβ for estrogen was higher than previously reported for channel catfish ERα. As determined by qualitative RT-PCR, the tissue distributions of ERα and ERβ were similar but not identical. Both ER subtypes were present in ovary and testis. ERα was found in all other tissues examined from juvenile and mature fish of both sexes. ERβ was also found in most tissues except, in most cases, whole blood and head kidney. Interestingly, the pattern of expression of ER subtypes in head kidney always corresponded to the pattern in whole blood. In conclusion, we isolated a channel catfish ERβ with ligand-binding affinity and tissue expression patterns different from ERα. Also, we confirmed the validity of our previously proposed general classification scheme for vertebrate ER into α and β subtypes and within each subtype, into teleost and tetrapod clades.

  14. Color threshold and ratio of S100 beta, MAP5, NF68/200, GABA & GAD. I. Distribution in inner ear afferents

    Science.gov (United States)

    Fermin, C. D.; Martin, D. S.; Hara, H.

    1997-01-01

    Afferents of chick embryos (Gallus domesticus) VIIIth nerve were examined at E3, E6, E9, E13, El7, and hatching (NH) for anti-S100 beta, anti-MAP5, anti-GABA, anti-GAD and anti-NF68/200 stain. Different ages were processed together to determine if the distribution of these antibodies changed during synaptogenesis and myelination. Color thresholding showed that saturation of pixels changed for S100 beta only 5%, for NF68/200 10%, and for MAP5, 10%, between E9-NH. Color ratio of NF68/200 over MAP5 was 1.00 at E13 and 0.25 at E16 and NH. S100 beta, GABA and GAD were co-expressed on nerve endings at the edge of the maculae and center of the cristae, whereas hair cells in the center of the maculae expressed either S100 beta or GABA, but not both. S100 beta/NF68/200 shared antigenic sites on the chalices, but NF68/200 expression was higher than S100 beta in the chalices at hatching. MAP5 was expressed in more neurons than NF68/200 at E11, whereas NF68/200 was more abundant than MAP5 at hatching. The results suggest that: 1) the immunoexpression of these neuronal proteins is modulated concomitantly with the establishment of afferent synapses and myelination; 2) S100 beta may serve a neurotrophic function in the chalices where it is co-expressed with the neurotransmitter GABA and its synthesizing enzyme GAD.

  15. Pharmacokinetics, tissue distribution, excretion, and metabolite profiling of PEGylated rFIX (nonacog beta pegol, N9-GP) in rats.

    Science.gov (United States)

    Sternebring, Ola; Christensen, Jesper Kammersgaard; Bjørnsdottir, Inga

    2016-09-20

    Nonacog beta pegol (N9-GP) is a novel recombinant factor IX conjugated with a 40-kDa branched polyethylene glycol (PEG) to extend plasma half-life (t½) compared with native FIX, developed for the treatment of haemophilia B. This is the first time distribution, metabolism, and excretion data of N9-GP have been presented. ADME studies were performed using single i.v. doses of radiolabelled N9-GP administered to rats, focussing on the biological fate of the 40-kDa PEG. Results indicated that N9-GP-related radioactivity was distributed throughout the body, being most abundant in highly vascularised tissues, and with lowest levels seen in the central nervous system. N9-GP was cleared from plasma within 1week after dosing, while total radioactivity was eliminated more slowly, in a more pronounced biphasic manner. N9-GP seems to be cleared via receptor-mediated uptake (e.g., in the liver) or via the reticuloendothelial system with subsequent proteolysis. PEG is thereafter either cleared alongside the protein or released back into circulation. Furthermore, N9-GP-related radioactivity was excreted in both faeces and urine as 40kDa PEG and degradation products. Some PEG-related radioactivity (not in any particular organ) was present in the carcass 12weeks postdose, consistent with the long terminal elimination t½ of plasma radioactivity. As shown here for N9-GP, and previously for other protein-PEG conjugate products, disposition kinetics of conjugates and individual constituents appears to be compound specific. In addition to the size/structure of the PEG and protein moieties, protein-specific clearance pathways may contribute to the disposition of intact conjugate and PEG moiety. PMID:27378188

  16. Further analysis of target strength measurements of Antarctic krill at 38 and 120 kHz: Comparison with deformed cylinder model and inference of orientation distribution

    OpenAIRE

    Chu, Dezhang; Foote, Kenneth G.; Stanton, Timothy K.

    1993-01-01

    Data collected during the krill target strength experiment [J. Acoust. Soc. Am. 87, 16–24 (1990)] are examined in the light of a recent zooplankton scattering model where the elongated animals are modeled as deformed finite cylinders [J. Acoust. Soc. Am. 86, 691–705 (1989)]. Exercise of the model under assumption of an orientation distribution allows absolute predictions of target strength to be made at each frequency. By requiring that the difference between predicted and measured target str...

  17. Extraction of Gamow-Teller strength distributions from 56Ni and 55Co via the (p,n) reaction in inverse kinematics

    Science.gov (United States)

    Sasano, M.; Perdikakis, G.; Zegers, R. G. T.; Austin, Sam M.; Bazin, D.; Brown, B. A.; Caesar, C.; Cole, A. L.; Deaven, J. M.; Ferrante, N.; Guess, C. J.; Hitt, G. W.; Honma, M.; Meharchand, R.; Montes, F.; Palardy, J.; Prinke, A.; Riley, L. A.; Sakai, H.; Scott, M.; Stolz, A.; Suzuki, T.; Valdez, L.; Yako, K.

    2012-09-01

    Background: Gamow-Teller (GT) transition strength distributions in stable and unstable pf-shell isotopes are key inputs for estimating electron-capture rates important for stellar evolution. Charge-exchange experiments at intermediate beam energies have long been used to test theoretical predictions for GT strengths, but previous experiments were largely restricted to stable nuclei. Since a large fraction of the nuclei relevant for astrophysical applications (including key nuclei such as 56Ni) are unstable, new methods are needed to perform charge-exchange experiments in inverse kinematics with unstable isotopes.Purpose: The 56Ni(p,n) and 55Co(p,n) reactions were measured in inverse kinematics in order to extract GT strengths for transitions to 56Cu and 55Ni, respectively. The extracted strength distributions were compared with shell-model predictions in the pf shell using the KB3G and GXPF1J interactions. By invoking isospin symmetry, these strength distributions are relevant for electron captures on the ground states of 56Ni and 55Ni to final states in 56Co and 55Co, respectively.Method: Differential cross sections and excitation energy spectra for the 56Ni(p,n) and 55Co(p,n) reactions were determined by measuring neutrons recoiling from a liquid hydrogen target into the Low Energy Neutron Detector Array. GT contributions to the spectra were extracted by using a multipole decomposition analysis and were converted to strengths by employing the proportionality between GT strength and differential cross section at zero linear momentum transfer.Results: GT strengths from 56Ni and 55Co were extracted up to excitation energies of 8 and 15 MeV, respectively. Shell-model calculations performed in the pf shell with the GXPF1J interaction reproduced the experimental GT strength distributions better than calculations with the KB3G interaction.Conclusions: A new technique for measuring (p,n) charge-exchange reactions on unstable nuclei was successfully developed. It can be

  18. The possibilities of autoradiographic imaging of the distribution of beta-emitting substances in dynamic processes by means of a gamma scintillation camera

    International Nuclear Information System (INIS)

    Possibilities of imaging the distribution of beta-emitting substances by means of a gamma scintillation camera are described. The sensitivity and the resolving power of the gamma scintillation camera was tested by means of a 140 KeV-high resolution collimator and a newly developed lead collimator with smaller hole diameter and hole distance. As an example for tests of imaging dynamic processes the transportation of 32P-labelled defoliant in a tomato plant is examined. (author)

  19. The Peculiar Shape of the Beta_(app)-z Distribution Seen in Radio Loud AGN Jets Is Explained Simply and Naturally In the Local Quasar Model

    CERN Document Server

    Bell, M B

    2008-01-01

    Recently, it was argued that the log(z)-m_{v} plot of 106,000 AGN galaxies could be interpreted as an evolutionary path followed by local AGN galaxies as they age. It was suggested that these objects are born as quasars with a high intrinsic redshift component that decreases with time. When the intrinsic component is large it causes them to be pushed above the standard candle line for brightest radio galaxies on a log(z)-m_{v} plot. In the jets of radio loud AGN galaxies, Beta_(app) is the apparent transverse velocity of the ejected material relative to the speed of light. In the cosmological redshift (CR) model the Beta_(app) vs z distribution has a peculiar shape, and there have been several attempts to explain it. In agreement with the model proposed to explain the log(z)-m_{v} plot, it is shown here that the peculiar shape of the Beta_(app)-z distribution in the CR model is exactly what is expected if the sources are local but their large intrinsic redshifts are assumed to be cosmological in the calculati...

  20. Beta Thalassemia

    Science.gov (United States)

    ... South Asian (Indian, Pakistani, etc.), Southeast Asian and Chinese descent. 1 Beta Thalassemia ßß Normal beta globin ... then there is a 25% chance with each pregnancy that their child will inherit two abnormal beta ...

  1. Tests of Hadronic Probes of GT Strength

    CERN Multimedia

    2002-01-01

    There are many important problems where one wishes to know the distribution of Gamow-Teller (GT) strength in circumstances where it cannot be measured directly (for example, because of energy-release limitations). Then one must rely on hadronic probes to infer the GT strength. It is therefore essential to test these probes as extensively as possible. The isospin-analog transitions in $^{37}$Ca $\\beta^{+}$ -decay and $^{37}$Cl$(p, n)$ provide an excellent ground for such a test. Recent $^{37}$Cl$ (p, n) $ studies, while qualitatively in agreement with our previous ISOLDE work on $^{37}$Ca $\\beta^{+} $ -decay, show quantitative discrepancies that appear to grow as the excitation energy in the residual nuclei increases. Because of the bulk of the GT strengh appears at these high excitation energies, it is important to extend the $\\beta$-decay data to even higher excitation energies where, because of rapidly diminishing phase-space, strong GT transitions correspond to very weak $\\beta$ -branches. We propose to do...

  2. Beta-decay properties of $^{25}$Si and $^{26}$P

    CERN Document Server

    Thomas, J C; Äystö, J; Béraud, R; Blank, B; Canchel, G; Czajkowski, S; Dendooven, P; Ensallem, A; Giovinazzo, J; Guillet, N; Honkanen, J; Jokinen, A; Laird, A M; Lewitowicz, M; Longour, C; De Santos, F O; Peräjärvi, K; democrite-00023307, ccsd

    2004-01-01

    The $\\beta$-decay properties of the neutron-deficient nuclei $^{25}$Si and $^{26}$P have been investigated at the GANIL/LISE3 facility by means of charged-particle and $\\gamma$-ray spectroscopy. The decay schemes obtained and the Gamow-Teller strength distributions are compared to shell-model calculations based on the USD interaction. B(GT) values derived from the absolute measurement of the $\\beta$-decay branching ratios give rise to a quenching factor of the Gamow-Teller strength of 0.6. A precise half-life of 43.7 (6) ms was determined for $^{26}$P, the $\\beta$- (2)p decay mode of which is described.

  3. Distribution of endogenous retinoids, retinoid binding proteins (RBP, CRABPI) and nuclear retinoid X receptor $\\beta$ (RXR$\\beta$) in the porcine embryo

    OpenAIRE

    Schweigert, Florian; Siegling, Christiane; Tzimas, Georg; Seeger, Johannes; Nau, Heinz

    2002-01-01

    International audience Retinoids are important signalling molecules in the development of limbs and in the determination of the anterior-posterior orientation of the embryo. The present study examined the content and distribution of retinoic acid, retinol and retinyl esters in porcine embryos during early gestation (gestation days 22-30) macroscopically and microscopically by its autofluorescence and by HPLC. Macroscopically, the yellowish-greenish autofluorescence characteristic of vitami...

  4. Beta-decay properties of Zr and Mo neutron-rich isotopes

    OpenAIRE

    Sarriguren, P.; Pereira, J

    2010-01-01

    Gamow-Teller strength distributions, beta-decay half-lives, and beta-delayed neutron emission are investigated in neutron-rich Zr and Mo isotopes within a deformed quasiparticle random-phase approximation. The approach is based on a self-consistent Skyrme Hartree-Fock mean field with pairing correlations and residual separable particle-hole and particle-particle forces. Comparison with recent measurements of half-lives stresses the important role that nuclear deformation plays in the descript...

  5. Numerical analysis of stress distribution in Cu-stabilized GdBCO CC tapes during anvil tests for the evaluation of transverse delamination strength

    International Nuclear Information System (INIS)

    Rare-earth–Ba–Cu–O (REBCO) based coated conductors (CCs) are now being used for electric device applications. For coil-based applications such as motors, generators and magnets, the CC tape needs to have robust mechanical strength along both the longitudinal and transverse directions. The CC tape in these coils is subjected to transverse tensile stresses during cool-down and operation, which results in delamination within and between constituent layers. In this study, in order to explain the behaviour observed in the evaluation of c-axis delamination strength in Cu-stabilized GdBCO CC tapes by anvil tests, numerical analysis of the mechanical stress distribution within the CC tape has been performed. The upper anvil size was varied in the analysis to understand the effect of anvil size on stress distribution within the multilayered CC tape, which is closely related to the delamination strength, delamination mode and delamination sites that were experimentally observed. The numerical simulation results showed that, when an anvil size covering the whole tape width was used, the REBCO coating film was subjected to the largest stress, which could result in low mechanical delamination and electromechanical delamination strengths. Meanwhile, when smaller-sized anvils were used, the copper stabilizer layer would experience the largest stress among all the constituent layers of the CC tape, which could result in higher mechanical and electromechanical delamination strengths, as well as high scattering of both of these delamination strengths. As a whole, the numerical simulation results could explain the damage evolution observed in CC tapes tested under transverse tensile stress, as well as the transverse tensile stress response of the critical current, Ic. (paper)

  6. Frequency distribution of sickle cell anemia, sickle cell trait and sickle/beta-thalassemia among anemic patients in Saudi Arabia

    OpenAIRE

    Elsayid, Mohieldin; Al-Shehri, Mohammed Jahman; Alkulaibi, Yasser Abdullah; Alanazi, Abdullah; Qureshi, Shoeb

    2015-01-01

    Background: Notwithstanding, the growing incidence of sickle cell hemoglobinopathies (SCH) such as sickle cell anemia (SCA) or sickle cell disease, sickle/beta-thalassemia; the exact prevalence remains obscure in Saudi Arabia. Hence, this study is an attempt to determine the frequency of SCA and sickle cell trait (SCT) among all anemic patients with SCH treated at the King Abdul-Aziz Medical City (KAMC), Riyadh, Saudi Arabia. Furthermore, the hemoglobin (Hb) S and other Hb patterns (Hb AS and...

  7. Bivariate distributions in statistical spectroscopy studies. Pt. 3. Non interacting particle strength densities for one-body transition operators

    International Nuclear Information System (INIS)

    In statistical spectroscopy, it was shown by French et al. (Ann. Phys., N.Y. 181, 235 (1988)) that the bivariate strength densities take a convolution form with the non interacting particle (NIP) strength density being convoluted with a spreading bivariate Gaussian due to interactions. Leaving aside the question of determining the parameters of the spreading bivariate Gaussian, one needs good methods for constructing the NIP bivariate strength densities IhO(E, E') (h is a one-body hamiltonian and O is a transition operator) in large shell model spaces. A formalism for constructing IhO is developed for one-body transition operators by using spherical orbits and spherical configurations. For rapid construction and also for applying the statistical theory in large shell model spaces IhO is decomposed into partial densities defined by unitary orbit configurations (unitary orbit is a set of spherical orbits). Trace propagation formulas for the bivariate moments Mrs with r + s ≤ 2 of the partial NIP strength densities, which will determine the Gaussian representation, are derived. In a large space numerical example with Gamow-Teller β- transition operator, the superposition of unitary orbit partial bivariate Gaussian densities is shown to give a good representation of the exact NIP strength densities. Trace propagation formulas for Mrs with r + s ≤ 4 are also derived in m-particle scalar spaces which are useful for many purposes. (orig.)

  8. The effect of strength and endurance training on insulin sensitivity and fat distribution in human immunodeficiency virus-infected patients with lipodystrophy

    DEFF Research Database (Denmark)

    Lindegaard, B; Hansen, T; Hvid, T;

    2008-01-01

    strength and endurance training on insulin sensitivity and fat distribution in HIV-infected patients with lipodystrophy. SUBJECTS AND METHODS: Twenty sedentary HIV-infected men with lipodystrophy were randomly assigned to supervised strength or endurance training three times a week for 16 wk. The primary...... increased with both endurance training (55.7 +/- 11 to 63.0 +/- 11 micromol glucose/kg lean mass.min, P = 0.02) and strength training (49.0 +/- 12 to 57.8 +/- 18 micromol glucose/kg lean mass.min, P = 0.005), irrespective of training modality (P = 0.24). Only strength training increased total lean mass 2.......1 kg [95% confidence interval (CI), 0.8-3.3], decreased total fat 3.3 kg (95% CI, -4.6 to -2.0), trunk fat 2.5 kg (95% CI, -3.5 to -1.5), and limb fat 0.75 kg (95% CI, -1.1 to -0.4). Strength training significantly decreased total and limb fat mass to a larger extent than endurance training (P < 0...

  9. First magnetic field models for recently discovered magnetic beta Cephei and slowly pulsating B stars

    CERN Document Server

    Hubrig, S; Schoeller, M; Briquet, M; Morel, T; De Cat, P

    2011-01-01

    In spite of recent detections of magnetic fields in a number of beta Cephei and slowly pulsating B (SPB) stars, their impact on stellar rotation, pulsations, and element diffusion is not sufficiently studied yet. The reason for this is the lack of knowledge of rotation periods, the magnetic field strength distribution and temporal variability, and the field geometry. New longitudinal field measurements of four beta Cephei and candidate beta Cephei stars, and two SPB stars were acquired with FORS2 at the VLT. These measurements allowed us to carry out a search for rotation periods and to constrain the magnetic field geometry for four stars in our sample.

  10. First measurement of several $\\beta$-delayed neutron emitting isotopes beyond N=126

    CERN Document Server

    Caballero-Folch, R; Agramunt, J; Algora, A; Ameil, F; Arcones, A; Ayyad, Y; Benlliure, J; Borzov, I N; Bowry, M; Calvino, F; Cano-Ott, D; Cortés, G; Davinson, T; Dillmann, I; Estrade, A; Evdokimov, A; Faestermann, T; Farinon, F; Galaviz, D; García, A R; Geissel, H; Gelletly, W; Gernhäuser, R; Gómez-Hornillos, M B; Guerrero, C; Heil, M; Hinke, C; Knöbel, R; Kojouharov, I; Kurcewicz, J; Kurz, N; Litvinov, Y; Maier, L; Marganiec, J; Marketin, T; Marta, M; Martínez, T; Martínez-Pinedo, G; Montes, F; Mukha, I; Napoli, D R; Nociforo, C; Paradela, C; Pietri, S; Podolyák, Zs; Prochazka, A; Rice, S; Riego, A; Rubio, B; Schaffner, H; Scheidenberger, Ch; Smith, K; Sokol, E; Steiger, K; Sun, B; Taín, J L; Takechi, M; Testov, D; Weick, H; Wilson, E; Winfield, J S; Wood, R; Woods, P; Yeremin, A

    2015-01-01

    The $\\beta$-delayed neutron emission probabilities of neutron rich Hg and Tl nuclei have been measured together with $\\beta$-decay half-lives for 20 isotopes of Au, Hg, Tl, Pb and Bi in the mass region N$\\gtrsim$126. These are the heaviest species where neutron emission has been observed so far. These measurements provide key information to evaluate the performance of nuclear microscopic and phenomenological models in reproducing the high-energy part of the $\\beta$-decay strength distribution. In doing so, it provides important constraints to global theoretical models currently used in $r$-process nucleosynthesis.

  11. Beta-decay properties of Zr and Mo neutron-rich isotopes

    CERN Document Server

    Sarriguren, P

    2010-01-01

    Gamow-Teller strength distributions, beta-decay half-lives, and beta-delayed neutron emission are investigated in neutron-rich Zr and Mo isotopes within a deformed quasiparticle random-phase approximation. The approach is based on a self-consistent Skyrme Hartree-Fock mean field with pairing correlations and residual separable particle-hole and particle-particle forces. Comparison with recent measurements of half-lives stresses the important role that nuclear deformation plays in the description of beta-decay properties in this mass region.

  12. An atlas of selected beta-ray spectra and depth-dose distributions in lithium fluoride and soft tissue generated by a fast Monte-Carlo-based sampling method

    Science.gov (United States)

    Samei, Ehsan; Kearfott, Kimberlee J.; Gillespie, Timothy J.; Chris Wang, C.-K.

    1996-12-01

    A method to generate depth-dose distributions due to beta radiation in LiF and soft tissue is proposed. In this method, the EGS4 Monte Carlo radiation transport code is initially used to generate a library of monoenergetic electron depth-dose distributions in the material for electron energies in the range of 10 keV to 5 MeV in 10 keV increments. A polynomial least-squares fit is applied to each distribution. In addition, a theoretical model is developed to generate beta-ray energy spectra of selected radionuclides. A standard Monte Carlo random sampling technique is then employed to sample the spectra and generate the depth-dose distributions in LiF and soft tissue. The proposed method has an advantage over more traditional methods in that the actual radiation transport in the media is performed only once for a set of monoenergetic cases and the beta depth-dose distributions are easily generated by sampling this previously-acquired database in a matter of minutes. This method therefore reduces the demand on computer resources and time. The method can be used to calculate depth-dose distribution due to any beta-emitting nuclide or combination of nuclides with up to ten beta components.

  13. Dosimetry analysis of distributions radials dose profiles of 90Sr + 90Y beta therapy applicators using the MCNP-4C code and radio chromium films

    International Nuclear Information System (INIS)

    Although they are no longer manufactured, the applicators of 90Sr + 90Y acquired in the decades of 1990 are still in use, by having half-life of 28.5 years. These applicators have calibration certificate given by their manufacturers, where few have been re calibrated. Thus it becomes necessary to accomplish thorough dosimetry of these applicators. This paper presents a dosimetric analysis distribution radial dose profiles for emitted by an 90Sr + 90Y beta therapy applicator, using the MCNP-4C code to simulate the distribution radial dose profiles and radio chromium films to get them experimentally . The results with the simulated values were compared with the results of experimental measurements, where both curves show similar behavior, which may validate the use of MCNP-4C and radio chromium films for this type of dosimetry. (author)

  14. Dosimetry analysis of distribution radial dose profiles of 90Sr + 90Y beta therapy applicators using the MCNP-4C code and radio chromium films

    International Nuclear Information System (INIS)

    Although they are no longer manufactured, the applicators of 90Sr +90Y acquired in the decades of 1990 are still in use, by having half-life of 28.5 years. These applicators have calibration certificate given by their manufacturers, where few have been recalibrated. Thus it becomes necessary to accomplish thorough dosimetry of these applicators. This paper presents a dosimetric analysis distribution radial dose profiles for emitted by an 90Sr+90Y beta therapy applicator, using the MCNP-4C code to simulate the distribution radial dose profiles and radiochromium films to get them experimentally . The results with the simulated values were compared with the results of experimental measurements, where both curves show similar behavior, which may validate the use of MCNP-4C and radiochromium films for this type of dosimetry. (author)

  15. Comparative study of Gamow-Teller strength distributions in the odd-odd nucleus 50V and its impact on electron capture rates in astrophysical environments

    CERN Document Server

    Nabi, Jameel-Un; 10.1103/PhysRevC.76.055803

    2011-01-01

    Gamow-Teller (GT) strength transitions are an ideal probe for testing nuclear structure models. In addition to nuclear structure, GT transitions in nuclei directly affect the early phases of Type Ia and Type-II supernovae core collapse since the electron capture rates are partly determined by these GT transitions. In astrophysics, GT transitions provide an important input for model calculations and element formation during the explosive phase of a massive star at the end of its life-time. Recent nucleosynthesis calculations show that odd-odd and odd-A nuclei cause the largest contribution in the rate of change of lepton-to-baryon ratio. In the present manuscript, we have calculated the GT strength distributions and electron capture rates for odd-odd nucleus 50V by using the pn-QRPA theory. At present 50V is the first experimentally available odd-odd nucleus in fp-shell nuclei. We also compare our GT strength distribution with the recently measured results of a 50V(d,2He)50Ti experiment, with the earlier work ...

  16. Relative band strengths from the study of intensity distribution in the A-X system of CrO

    Science.gov (United States)

    Bagare, S. P.; Murthy, N. Sreedhara

    1984-08-01

    Relative integrated intensities are measured for ten bands in the vibrational structure of the astrophysically significant A 5π-X 5π system of CrO by the technique of photographic photometry. Vibrational transition probabilities are computed using the revised molecular constants of the electronic states. Using these results, the variation of electronic transition moment with the internuclear separation is found to be Re( r) = const. × (1-0.398 r) in the range 1.60 Å < r < 1.72 Å. A smoothed array of band strengths is presented.

  17. Determination of the electromagnetic dipole strength distribution in medium-heavy atomic nuclei by means of nuclear resonance fluorescence

    International Nuclear Information System (INIS)

    During the last hundred years several models were developed to describe the configuration of nuclei. These models have to make predictions, which should be comparable with experiments. As a standard type of experiment the nuclear resonance fluorescence was established. A nucleus is excited by irradiation with photons. By emitting one or more photons the nucleus decays back to the ground state. With this method it is possible to measure energy levels and to determine the strength of their excitation. A continuum of unresolved peaks gives additional strength. The existing setup at the linear electron accelerator ELBE of the Forschungszentrum Dresden-Rossendorf uses bremsstrahlung, produced as a secondary beam in a thin Niobium foil. During the years 2008/09 experiments on the nuclei of 86Kr and 136Ba took place there. In this work they will be analyzed. Photon flux and efficiency determination have been done as well as simulations on detector response and non-nuclear scattered background events. For this purpose the GEANT4 package was used. Finally the resulting cross sections were corrected for branching and feeding.

  18. Non-parametric asymptotic statistics for the Palm mark distribution of \\beta-mixing marked point processes

    OpenAIRE

    Heinrich, Lothar; Lück, Sebastian; Schmidt, Volker

    2012-01-01

    We consider spatially homogeneous marked point patterns in an unboundedly expanding convex sampling window. Our main objective is to identify the distribution of the typical mark by constructing an asymptotic \\chi^2-goodness-of-fit test. The corresponding test statistic is based on a natural empirical version of the Palm mark distribution and a smoothed covariance estimator which turns out to be mean-square consistent. Our approach does not require independent marks and allows dependences bet...

  19. Strength, decay branching ratios, and angular distribution of the 0.987 MeV resonance in the {sup 14}N(p,{gamma}){sup 15}O reaction

    Energy Technology Data Exchange (ETDEWEB)

    Marta, Michele; Bemmerer, Daniel; Beyer, Roland; Erhard, Martin; Grosse, Eckart; Hannaske, Roland; Junghans, Arnd Rudolf; Nair, Chithra; Schwengner, R.; Trompler, Erik; Wagner, Andreas; Yakorev, Dmitry [Forschungszentrum Dresden-Rossendorf (FZD), Dresden (Germany); Broggini, Carlo; Caciolli, Antonio; Menegazzo, Roberto [INFN Sezione di Padova, Padova (Italy); Fueloep, Zsolt; Gyuerky, Gyoergy; Szuecs, Tamas [Atomki, Debrecen (Hungary)

    2009-07-01

    The {sup 14}N(p,{gamma}){sup 15}O reaction controls the rate of the hydrogen burning CNO cycle. This reaction has recently been re-studied at E<500 keV at different facilities, including LUNA. However, also data at higher energy play a role in determining the extrapolated cross section in the R-matrix framework. Here we report on a new measurement of the absolute strength, decay branching ratio, and angular distribution of the E=0.987 MeV (E{sub x} = 8.284 MeV) resonance carried out at the high-current FZD Tandetron.

  20. Irreversible volume growth in polymer-bonded powder systems: effects of crystalline anisotropy, particle size distribution, and binder strength

    Energy Technology Data Exchange (ETDEWEB)

    Maiti, A; Gee, R H; Hoffman, D; Fried, L E

    2007-08-22

    Pressed-powdered crystallites of intrinsically anisotropic materials have been shown to undergo irreversible volume expansion when subjected to repeated cycles of heating and cooling. We develop a coarse-grained (micron-scale) interaction Hamiltonian for this system and perform molecular dynamics simulations, which quantitatively reproduce the experimentally observed irreversible growth. The functional form and values of the interaction parameters at the coarse-grained level are motivated by our knowledge at the atomic/molecular scale, and allows a simple way to incorporate the effect of polymeric binder. We demonstrate that irreversible growth happens only in the presence of intrinsic crystalline anisotropy of the powder material, is mediated by particles much smaller than the average crystallite size, and can be significantly reduced in the presence of high-strength polymeric binder with elevated glass transition temperatures.

  1. Investigation on the temperature distribution and strength of flat steel ribbon wound cryogenic high-pressure vessel

    Institute of Scientific and Technical Information of China (English)

    CUI Xiao-long; CHEN Guang-ming

    2007-01-01

    By analyzing heat transfer on the wall of flat steel ribbon wound vessel (FSRWV), a numerical model of temperature distribution on the entire wall (including inner core wall, flat steel ribbons, outside cylinder of jacket and insulating layer) was established by the authors. With the model, the temperature distribution and the length change in the vessel walls and flat steel ribbons in low temperature are calculated and analyzed. The results show that the flat steel ribbon wound cryogenic high-pressure vessel is simpler in structure, safer and easier to manufacture than those of conventional ones.

  2. Distribution of Refugees Very Uneven among EU Member States - Even When Accounting for Economic Strength and Total Population

    OpenAIRE

    Karl Brenke

    2015-01-01

    The European Union is currently experiencing its largest influx of asylum seekers in years. Yet the distribution of these refugees across the member states is highly uneven: Large countries such as the United Kingdom, France, Italy, and Spain, as well as the Eastern European countries (apart from Hungary), have received relatively few asylum seekers. Far more refugees are headed to Central Europe, Sweden, and the small countries on the outskirts of the EU (Malta, Cyprus, and Bulgaria). German...

  3. Distribution of refugees very uneven among EU member states - even when accounting for economic strength and total population

    OpenAIRE

    Brenke, Karl

    2015-01-01

    The European Union is currently experiencing its largest influx of asylum seekers in years. Yet the distribution of these refugees across the member states is highly uneven: Large countries such as the United Kingdom, France, Italy, and Spain, as well as the Eastern European countries (apart from Hungary), have received relatively few asylum seekers. Far more refugees are headed to Central Europe, Sweden, and the small countries on the outskirts of the EU (Malta, Cyprus, and Bulgaria). German...

  4. Resistance training & beta-hydroxy-beta-methylbutyrate supplementation on hormones

    OpenAIRE

    Hamid Arazi; Hadi Rohani; Ahmad Ghiasi; Nasrin Abdi Keikanloo

    2015-01-01

    RESUMOIntroduction:In recent years, there was an increased interest on the effects of beta-hydroxy-beta-methylbutyrate (HMB) supplementation on skeletal muscle due to its anti-catabolic effects.Objectives:To investigate the effect of HMB supplementation on body composition, muscular strength and anabolic-catabolic hormones after resistance training.Methods:Twenty amateur male athletes were randomly assigned to supplement and control groups in a double-blind crossover design and participated i...

  5. Distribution of serum lipids and lipoproteins in patients with beta thalassaemia major; an epidemiological study in young adults from Greece

    Directory of Open Access Journals (Sweden)

    Barbetseas John

    2004-03-01

    Full Text Available Abstract Background Beta-thalassaemia major (b-TM has been defined as a combination of chronic hemolytic anemia, iron storage disease and myocarditis, and it has been associated with premature death especially due to heart failure. To the best of our knowledge the status of blood lipids in these patients has rarely been investigated. Thus, we assessed the levels of lipids and lipoproteins in a sample of cardiovascular disease free adult men and women with b-TM. Methods During 2003 we enrolled 192 consecutive patients with b-TM that visited our Institution for routine examinations. The Institution is considered the major reference center for b-TM in Greece. Of the 192 patients, 88 were men (25 ± 6 years old and 104 women (26 ± 6 years old. Fasting blood lipid levels were measured in all participants. Results Data analysis revealed that 4% of men and 2% of women had total serum cholesterol levels > 200 mg/dl, and 11% of men and 17% of women had triglyceride levels > 150 mg/dl. In addition, mean HDL cholesterol levels were 32 ± 11 mg/dl in men and 38 ± 10 mg/dl in women, lipoprotein-a levels were 8.3 ± 9 mg/dl in men and 8.8 ± 9 mg/dl in women, apolipoprotein-A1 levels were 111 ± 17 mg/dl in men and 123 ± 29 mg/dl in women, and apolipoprotein-B levels were 60 ± 20 mg/dl in men and 59 ± 14 mg/dl in women. Total-to-HDL cholesterol ratios were 3.7 ± 1.2 and 3.8 ± 1.5 in men and women, respectively. Conclusions The majority of the patients had blood lipid levels (by the exception of HDL-cholesterol within the normal range, and consequently the prevalence of lipid and lipoprotein abnormalities was much lower as compared to the general population of the same age. Interestingly, is that the total – to HDL cholesterol ratio was high in our patients, and may underline the importance of this index for the prognosis of future cardiac events in these patients.

  6. Distribution and dynamics of branchial ionocytes in houndshark reared in full-strength and diluted seawater environments.

    Science.gov (United States)

    Takabe, Souichirou; Inokuchi, Mayu; Yamaguchi, Yoko; Hyodo, Susumu

    2016-08-01

    In teleost fishes, it is well-established that the gill serves as an important ionoregulatory organ in addition to its primary function of respiratory gas exchange. In elasmobranchs, however, the ionoregulatory function of the gills is still incompletely understood. Although two types of ionocytes, Na(+)/K(+)-ATPase (NKA)-rich (type-A) cell and vacuolar-type H(+)-ATPase (V-ATPase)-rich (type-B) cell, have been found in elasmobranch fishes, these cells were considered to function primarily in acid-base regulation. In the present study, we examined ion-transporting proteins expressed in ionocytes of Japanese-banded houndshark, Triakis scyllium, reared in full-strength seawater (SW) and transferred to diluted (30%) SW. In addition to the upregulation of NKA and Na(+)/H(+) exchanger type 3 (NHE3) mRNAs in the type-A ionocytes, we found that Na(+), Cl(-) cotransporter (NCC, Slc12a3) is expressed in a subpopulation of the type-B ionocytes, and that the expression level of NCC mRNA was enhanced in houndsharks transferred to a low-salinity environment. These results suggest that elasmobranch gill ionocytes contribute to NaCl uptake in addition to the already described function of acid-base regulation, and that NCC is most probably one of the key molecules for hyper-osmoregulatory function of elasmobranch gills. The existence of two types of ionocytes (NHE3- and NCC-expressing cells) that are responsible for NaCl absorption seems to be a common feature in both teleosts and elasmobranchs for adaptation to a low salinity environment. A possible driving mechanism for NCC in type-B ionocytes is discussed. PMID:27040185

  7. 基于β-二项分布的结构易损性分析%Structural fragility estimation with beta-binomial distribution

    Institute of Scientific and Technical Information of China (English)

    刘骁骁; 吴子燕; 王其昂

    2014-01-01

    易损性曲线建立过程中受激励不确定性和结构参数不确定性的影响,会引起结构或构件观测结果的统计相关性。为此,本文提出基于β-二项分布的结构易损性分析方法。该方法根据性能量化指标阈值和 Monte Carlo模拟确定震后观测结果,采用β-二项分布探讨震后观测值的统计相关性;结合对数回归模型,推导了改进β-二项分布的累积分布函数,计算结构失效概率;通过累积对数正态分布拟合易损性曲线,比较了观测失效样本数与观测失效概率统计相关性对易损性的影响,并与未考虑统计相关性的传统易损性曲线作对比。某8层钢筋混凝土框架-剪力墙结构的算例表明,考虑统计相关性的易损性较传统易损性偏大,且结构遭受8度以上地震作用时,考虑失效样本数统计相关性的易损性使预测结果更为保守,利于工程安全。%The uncertainty of seismic excitation and structural parameters in the process of establishing fragility curves leads to statistical dependence among observations,which has been neglected in past applications.In this paper,a new methodology based on beta-binomial distribution to calculate structural fragility is presented.Observations indicating the states (failure or survival)are confirmed via quantita-tive indicators threshold as well as Monte Carlo after each earthquake.Beta-Binomial distribution is ad-dressed to discuss the statistical dependence among observations.Improved cumulative beta-binomial dis-tribution function is derivation to calculate failure probability combined with logistic regression model. Seismic vulnerability curve can be fitted by means of cumulative lognormal distribution,which is com-pared with traditional fragility that of neglecting statistical dependence among observations and fragility curve considering statistical dependence among observed failure rates.A seat eight floors reinforced con

  8. Combination of digital autoradiography and alpha track analysis to reveal the distribution of definite alpha- and beta-emitting nuclides in contaminated samples

    International Nuclear Information System (INIS)

    Digital autoradiography using Imaging Plate is commonly employed for searching 'hot' particles in the contaminated soil, sediment and aerosol probes. However digital radiography images combined with Alpha Track radiography data could provide much more information about micro-distribution of different alpha- and beta- nuclides. The discrimination method to estimate the distribution of radionuclides that are the main contributors to the total radioactivity (90Sr/90Y, 137Cs, 241Am) has been developed on the case of artificial reservoir V-17 (PA 'Mayak'). The bottom sediments and hydrobionts probes collected from V-17 along with the standards of 137Cs, 90Sr/90Y and 241Am have been exposed for a short time (15 min) using a stack of 3 Imaging Plates (Cyclone Plus Storage Phosphor System, Perkin Elmer). The attenuation of photostimulated luminescence (PSL) intensity from layer to layer of the Imaging Plates depends on the type and energy of radiation. Integrated approach using PSL attenuation in the samples and standards (digital radiography) along with Alpha Track radiography and gamma-spectroscopy of the preparation was used to estimate the contribution of the main nuclides in specific parts of contaminated samples. The observation of the 90Sr/90Y and 137Cs activity maxima could help to find the phases which are responsible for preferential sorption of the nuclides. Document available in abstract form only. (authors)

  9. Distributions and size scalings for strength in a one-dimensional random lattice with load redistribution to nearest and next-nearest neighbors

    International Nuclear Information System (INIS)

    Lattice and network models with elements that have random strength are useful tools in explaining various statistical features of failure in heterogeneous materials, including the evolution of failure clusters and overall strength distributions and size effects. Models have included random fuse and spring networks where Monte Carlo simulation coupled to scaling analysis from percolation theory has been a common approach. Unfortunately, severe computational demands have limited the network sizes that can be treated. To gain insight at large size scales, interest has returned to idealized fiber bundle models in one dimension. Many models can be solved exactly or asymptotically in increasing size n, but at the expense of major simplification of the local stress redistribution mechanism. Models have typically assumed either equal load-sharing among nonfailed elements, or nearest-neighbor, local load-sharing (LLS) where a failed element redistributes its load onto its two nearest flanking survivors. The present work considers a one-dimensional fiber bundle model under tapered load sharing (TLS), which assumes load redistribution to both the nearest and next-nearest neighbors in a two-to-one ratio. This rule reflects features found in a discrete mechanics model for load transfer in two-dimensional fiber composites and planar lattices. We assume that elements have strength 1 or 0, with probability p and q=1-p, respectively. We determine the structure and probabilities for critical configurations of broken fibers, which lead to bundle failure under a given load. We obtain rigorous asymptotic results for the strength distribution and size effect, as n→∞, with precisely determined constants and exponents. The results are a nontrivial extension of those under LLS in that failure clusters are combinatorially much more complicated and contain many bridging fibers. Consequently, certain probabilities are eigenvalues from recursive equations arising from the structure of TLS

  10. Strength Training

    Science.gov (United States)

    ... person's own weight to build muscles and strength. Olympic lifting, or powerlifting, which people often think of ... in the group effectively. Here are some basic rules to follow in strength training: Start with body ...

  11. Long-tailed distribution of synaptic strength reveals origin and functional roles of ongoing fluctuation in cortical circuit

    Science.gov (United States)

    Teramae, Jun-nosuke

    2016-06-01

    Neurons in the cortical circuit continuous to generate irregular spike firing with extremely low firing rate (about 1-2 Hz) even when animals neither receive any external stimuli nor they do not show any significant motor movement. The ongoing activity is often called neuronal noise because measured spike trains are often highly irregular and also spike timings are highly asynchronous among neurons. Many experiments imply that neural networks themselves must generate the noisy activity as an intrinsic property of cortical circuit. However, how a network of neurons sustains the irregular spike firings with low firing rate remains unclear. Recently, by focusing on long-tailed distribution of amplitude of synaptic connections or EPSP (Excitatory Post-Synaptic Potential), we successfully revealed that due to coexistence of a few extremely strong synaptic connections and majority of weak synapses, nonlinear dynamics of population of spiking neurons can have a nontrivial stable state that corresponding to the intrinsic ongoing fluctuation of the cortical circuit. We also found that due to the fluctuation fidelity of spike transmission between neurons are optimized. Here, we report our recent findings of the ongoing fluctuation from viewpoints of mathematical and computational side.

  12. The Grilled Effect of Particle's Distribution of Calsine Coke's at 900oC Temperature upon the Electric Resistivity, Hardness and CompressiveStrength Analysis

    International Nuclear Information System (INIS)

    Investigation of Calsine Coke's particle's distribution by grilledtreatment at 900 oC temperature upon the electric resistivity, hardness andcompressive strength analysis had been done. The Calsine Coke's were crushedand sieved to get a particle size about 63; 90; 106 μm, then mixed thevariety size particle with 33 % tar pitch 125 μm, be heated, shaped andpressed to be pellet. The pellets were grilled at 900 oC temperature during30 minutes and then these were analyzed. The whole analysis using 2-b mixedwas the best, particle ratio were 63:106 = 1:2 and pointed the electricresistivity 2.63 Ωm, the hardness 5.9 kg/mm2 and the compressivestrength 1600 N. (author)

  13. Heart rate distribution and predictors of resting heart rate after initiation of beta-blocker treatment in patients with coronary artery disease: REsults of Sympathetic Evaluation And Research of China(RESEARCH) study

    Institute of Scientific and Technical Information of China (English)

    ZHAO Ying-xin; LI Yue-ping; GAO Fei; MA Han-ying; WANG Zhi-jian; HAN Hong-ya; SHEN Hua

    2013-01-01

    Background The importance of heart rate as secondary prevention strategies for patients with coronary artery disease (CAD) is emphasized by multiple guidelines.However,limited information is available on the heart rate distribution and the change patterns of resting heart rate when initiating beta-blocker therapy among Chinese patients with CAD.Methods The REsults of Sympathetic Evaluation And Research of China (RESEARCH) study is a multi-centre,prospective,observational study involving 147 centers in 23 cities across China.All eligible beta-blocker naive patients were prescribed with metroprolol succinate.Initial dosage and target heart rate were selected at the discretion of their physicians in charge according to their usual institutional practice.The heart rate distribution and the change patterns of resting heart rate after initiation of beta-blocker therapy were observed.Results The majority of patients (63.6%) were prescribed with 47.5 mg metroprolol succinate.At baseline,there were only 17.4% of patients whose heart rate was less than 70 beats per minute,and the proportion reached 42.5% and 79.1%,one month and two months after initiation of beta-blockers,respectively.Multivariate linear regression analysis showed that baseline heart rate (B=0.900,SE=0.006,t=141.787,P<0.0001) and the dosage (B=-0.007,SE=0.002,t=-3.242,P=0.001) were independent predictors of resting heart rate 2 months after beta-blocker therapy.Conclusions Resting heart rate is not optimally controlled in a broadly representative cohort of Chinese outpatients with CAD even after initiation of β-blocker therapy,and baseline heart rate and the dosage of beta-blocker are both independent predictors of resting heart rate after β-blocker therapy.

  14. Human type 2 17beta-hydroxysteroid dehydrogenase mRNA and protein distribution in placental villi at mid and term pregnancy

    Directory of Open Access Journals (Sweden)

    Plante Julie

    2007-07-01

    Full Text Available Abstract Background During human pregnancy, the placental villi produces high amounts of estradiol. This steroid is secreted by the syncytium, which is directly in contact with maternal blood. Estradiol has to cross placental foetal vessels to reach foetal circulation. The enzyme 17beta-hydroxysteroid dehydrogenase type 2 (17beta-HSD2 was detected in placental endothelial cells of foetal vessels inside the villi. This enzyme catalyzes the conversion of estradiol to estrone, and of testosterone to androstenedione. It was proposed that estradiol level into foetal circulation could be regulated by 17beta-HSD2. Methods We obtained placentas from 10 to 26 6/7 weeks of pregnancy from women undergoing voluntary termination of pregnancy, term placentas were collected after normal spontaneous vaginal deliveries. We quantified 17beta-HSD2 mRNA levels in mid-gestation and term human placenta by RT-QPCR. We produced a new anti-17beta-HSD2 antibody to study its spatio-temporal expression by immunohistochemistry. We also compared steroid levels (testosterone, estrone and estradiol and 17beta-HSD2 mRNA and protein levels between term placenta and endometrium. Results High 17beta-HSD2 mRNA and protein levels were found in both mid-gestation and term placentas. However, we showed that 17beta-HSD2 mRNA levels increase by 2.27 fold between mid-gestation and term. This period coincides with a transitional phase in the development of the villous vasculature. In mid-gestation placenta, high levels of 17beta-HSD2 were found in mesenchymal villi and immature intermediate villi, more precisely in endothelial cells of the stromal channel. At term, high levels of 17beta-HSD2 were found in the numerous sinusoidal capillaries of terminal villi. 17beta-HSD2 mRNA and protein levels in term placentas were respectively 25.4 fold and 30 to 60 fold higher than in the endometrium. Steroid levels were also significantly higher in term placenta than in the endometrium. Conclusion

  15. The decisive role of the distribution of Al in the framework of beta zeolites on the structure and activity of Co ion species in propane-SCR-NOx in the presence of water vapour

    Czech Academy of Sciences Publication Activity Database

    Čapek, Libor; Dědeček, Jiří; Sazama, Petr; Wichterlová, Blanka

    2010-01-01

    Roč. 272, č. 1 (2010), s. 44-54. ISSN 0021-9517 R&D Projects: GA AV ČR KAN100400702; GA AV ČR IAA400400904 Grant ostatní: EU Network of Excellence IDECAT(XE) NMP 3-CT-2005-011730 Institutional research plan: CEZ:AV0Z40400503 Keywords : Co-beta zeolites * Al distribution * SCR -NOx Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 5.415, year: 2010

  16. Effect of precipitation on strength and ductility in a Mg-Zn-Y alloy

    Energy Technology Data Exchange (ETDEWEB)

    Rosalie, Julian M. [Microstructure Design Group, Structural Materials Unit, National Institute for Materials Science (NIMS), Sengen 1-2-1, Tsukuba, Ibaraki 305-0047 (Japan); Somekawa, Hidetoshi [Toughness Design Group, Structural Materials Unit, National Institute for Materials Science (NIMS), Sengen 1-2-1, Tsukuba, Ibaraki 305-0047 (Japan); Singh, Alok, E-mail: alok.singh@nims.go.jp [Microstructure Design Group, Structural Materials Unit, National Institute for Materials Science (NIMS), Sengen 1-2-1, Tsukuba, Ibaraki 305-0047 (Japan); Mukai, Toshiji [Dept. Mechanical Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe City 657-8501 (Japan)

    2013-02-15

    Highlights: Black-Right-Pointing-Pointer Strain and ageing used to control {beta}{sub 1}{sup Prime} precipitate size and distribution. Black-Right-Pointing-Pointer Precipitate size and distribution are correlated with strength and ductility. Black-Right-Pointing-Pointer Larger volume fraction of {beta}{sub 1}{sup Prime} precipitates introduced by solute re-partitioning. Black-Right-Pointing-Pointer 32% increase in yield strength achieved by 5% pre-ageing deformation. - Abstract: The effect of pre-ageing deformation on the size and distribution of {beta}{sub 1}{sup Prime} precipitates and subsequently on the resulting strength and ductility have been measured in a Mg-3.0at.%Zn-0.5at.%Y alloy. The alloy was extruded and then subjected to a T8 heat treatment comprised of a solution-treatment, cold-work and artificial ageing. Extrusion was used to introduce texture, ensuring that deformation occurred via slip rather than twinning. Samples were subjected to controlled uniaxial deformation and then isothermally aged to peak hardness. Precipitate length, diameter and number density were measured and evaluated in terms of the strength and ductility of the alloy. The nucleation of the {beta}{sub 1}{sup Prime} precipitates in peak-aged condition without pre-ageing deformation (i.e. T6 treatment) was poor, with only 0.5% volume fraction, compared to approximately 3.5% in T6 treated binary Mg-3.0at.%Zn alloy. The microstructure of the Mg-Zn-Y alloy was less refined, with larger diameter precipitates and lower {beta}{sub 1}{sup Prime} number densities than a binary Mg-3.0at.%Zn alloy. Deformation to 5% plastic strain increased the volume fraction of {beta}{sub 1}{sup Prime} precipitates to approximately 2.3% and refined the {beta}{sub 1}{sup Prime} precipitate length and diameter. The combination of these effects increased the yield strength after isothermal ageing from 217 MPa (0% cold-work) to 287 MPa (5% cold-work). The yield stress increased linearly with reciprocal

  17. Distribution of beta-endorphin and substance P in the shoulder joint of the dog before and after a low impact exercise programme.

    Science.gov (United States)

    Karahan, S; Kincaid, S A; Baird, A N; Kammermann, J R

    2002-04-01

    Beta-endorphin and substance P were immunolocalized in the articular cartilage, synovial membrane and fibrous joint capsule of dogs. Twelve adult greyhounds were randomly assigned to one of three groups: control, limited exercise, or regimented exercise. On day 0, biopsies of articular cartilage and joint capsule were obtained from the left shoulder joints of dogs receiving limited and regimented exercise. On day 72, biopsies of joint capsule from right and left shoulders and articular cartilage from the right shoulder joint were analysed for the presence of glycosaminoglycans (GAG) and for immunolocalization of substance P and beta-endorphin. Regimented exercise increased the presence of GAGs and immunolocalization of substance P and beta-endorphin in articular cartilage and synovial membrane compared to day 0 biopsies and untreated controls. Localization of beta-endorphin became prominent in and around the chondrocytes. Substance P was increased in chondrocytes and extracellular matrix. Concomitant changes in localization of beta-endorphin and substance P may have a role in the modulation of the microphysiological environment, metabolism, or function of joint tissues in response to low-impact exercise. PMID:12047242

  18. In vitro susceptibility and distribution of beta-lactamases in Enterobacteriaceae causing intra-abdominal infections in North America 2010-2011.

    Science.gov (United States)

    Hoban, Daryl J; Badal, Robert; Bouchillon, Sam; Hackel, Meredith; Kazmierczak, Krystyna; Lascols, Christine; Hawser, Stephen

    2014-07-01

    The Study for Monitoring Antimicrobial Resistance Trends has been monitoring the activity of antimicrobials indicated for the treatment of intra-abdominal infections since 2004. This report documents the in vitro activity of several recommended antimicrobials against 3449 gram-negative bacilli isolated from the 30 and 25 participating sites in North America in 2010-2011, respectively, and characterizes the extended-spectrum beta-lactamases (ESBL) identified in ESBL-positive and ertapenem-non-susceptible isolates of Enterobacteriaceae. Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Proteus mirabilis, Klebsiella oxytoca, Citrobacter freundii, Enterobacter aerogenes, Serratia marcescens, and Morganella morgannii were the most common species isolated. The incidence of beta-lactamase production was 8.8% and 8.9% for E. coli and K. pneumoniae, respectively. Overall the most active antimicrobials were amikacin, piperacillin-tazobactam, imipenem, and ertapenem, although beta-lactamase production reduced the activity of most agents. Characterization of beta-lactamase genes determined that bla(SHV), bla(CTX-M), bla(AmpC), and bla(KPC) were commonly found in most beta-lactamase-positive isolates. PMID:24813688

  19. Study of the time and space distribution of {beta}{sup +} emitters from 80MeV/u carbon ion beam irradiation on PMMA

    Energy Technology Data Exchange (ETDEWEB)

    Agodi, C. [Laboratori Nazionali del Sud dell' INFN, Catania (Italy); Bellini, F. [Dipartimento di Fisica, Sapienza Universita di Roma, Roma (Italy); INFN Sezione di Roma, Roma (Italy); Cirrone, G.A.P. [Laboratori Nazionali del Sud dell' INFN, Catania (Italy); Collamati, F. [Dipartimento di Fisica, Sapienza Universita di Roma, Roma (Italy); INFN Sezione di Roma, Roma (Italy); Cuttone, G. [Laboratori Nazionali del Sud dell' INFN, Catania (Italy); De Lucia, E. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); De Napoli, M. [Laboratori Nazionali del Sud dell' INFN, Catania (Italy); Di Domenico, A.; Faccini, R.; Ferroni, F. [Dipartimento di Fisica, Sapienza Universita di Roma, Roma (Italy); INFN Sezione di Roma, Roma (Italy); Fiore, S. [Dipartimento di Fisica, Sapienza Universita di Roma, Roma (Italy); Gauzzi, P. [Dipartimento di Fisica, Sapienza Universita di Roma, Roma (Italy); INFN Sezione di Roma, Roma (Italy); Iarocci, E. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); Dipartimento di Scienze di Base e Applicate per l' Ingegneria, Sapienza Universita di Roma, Roma (Italy); Marafini, M., E-mail: michela.marafini@roma1.infn.it [Museo Storico della Fisica e Centro Studi e Ricerche ' E. Fermi' , Roma (Italy); Mattei, I. [Dipartimento di Fisica, Roma Tre Universita di Roma, Roma (Italy); Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); Paoloni, A. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); and others

    2012-07-15

    Proton and carbon ion therapy is an emerging technique used for the treatment of solid cancers. The monitoring of the dose delivered during such treatments and the on-line knowledge of the Bragg peak position is still a matter of research. A possible technique exploits the collinear 511keV photons produced by positrons annihilation from {beta}{sup +} emitters created by the beam. This paper reports rate measurements of the 511keV photons emitted after the interactions of a 80MeV/u fully stripped carbon ion beam at the Laboratori Nazionali del Sud (LNS) of INFN, with a poly-methyl methacrylate target. The time evolution of the {beta}{sup +} rate was parametrized and the dominance of {sup 11}C emitters over the other species ({sup 13}N, {sup 15}O, {sup 14}O) was observed, measuring the fraction of carbon ions activating {beta}{sup +} emitters to be (10.3{+-}0.7) Multiplication-Sign 10{sup -3}. The average depth in the PMMA of the positron annihilation from {beta}{sup +} emitters was also measured, D{sub {beta}{sup +}}=5.3{+-}1.1mm, to be compared to the expected Bragg peak depth D{sub Bragg}=11.0{+-}0.5mm obtained from simulations.

  20. Study of the time and space distribution of $\\beta^+$ emitters from $80\\ \\mega\\electronvolt/$u carbon ion beam irradiation on PMMA

    CERN Document Server

    Agodi, C; Cirrone, G A P; Collamati, F; Cuttone, G; De Lucia, E; De Napoli, M; Di Domenico, A; Faccini, R; Ferroni, F; Fiore, S; Gauzzi, P; Iarocci, E; Marafini, M; Mattei, I; Paoloni, A; Patera, V; Piersanti, L; Romano, F; Sarti, A; Sciubba, A; Voena, C

    2012-01-01

    Proton and carbon ion therapy is an emerging technique used for the treatment of solid cancers. The monitoring of the dose delivered during such treatments and the on-line knowledge of the Bragg peak position is still a matter of research. A possible technique exploits the collinear $511\\ \\kilo\\electronvolt$ photons produced by positrons annihilation from $\\beta^+$ emitters created by the beam. This paper reports rate measurements of the $511\\ \\kilo\\electronvolt$ photons emitted after the interactions of a $80\\ \\mega\\electronvolt / u$ fully stripped carbon ion beam at the Laboratori Nazionali del Sud (LNS) of INFN, with a Poly-methyl methacrylate target. The time evolution of the $\\beta^+$ rate was parametrized and the dominance of $^{11}C$ emitters over the other species ($^{13}N$, $^{15}O$, $^{14}O$) was observed, measuring the fraction of carbon ions activating $\\beta^+$ emitters $A_0=(10.3\\pm0.7)\\cdot10^{-3}$. The average depth in the PMMA of the positron annihilation from $\\beta^+$ emitters was also meas...

  1. Resistance training & beta-hydroxy-beta-methylbutyrate supplementation on hormones

    Directory of Open Access Journals (Sweden)

    Hamid Arazi

    2015-10-01

    Full Text Available RESUMOIntroduction:In recent years, there was an increased interest on the effects of beta-hydroxy-beta-methylbutyrate (HMB supplementation on skeletal muscle due to its anti-catabolic effects.Objectives:To investigate the effect of HMB supplementation on body composition, muscular strength and anabolic-catabolic hormones after resistance training.Methods:Twenty amateur male athletes were randomly assigned to supplement and control groups in a double-blind crossover design and participated in four weeks resistance training. Before and after the test period fasting blood samples were obtained to determine anabolic (the growth hormone and testosterone and catabolic (cortisol hormones, and fat mass, lean body mass (LBM and muscular strength were measured. Dependent and independent t-tests were used to analyze data.Results:After the training period, there were no significant differen-ces between the groups with respect to fat mass, LBM and anabolic-catabolic hormones. HMB supplementation resulted in a significantly greater strength gain (p≤0.05.Conclusion:Greater increase in strength for HMB group was not accompanied by body composition and basal circulating anabolic-catabolic hormonal changes. It seems that HMB supplementation may have beneficial effects on neurological adaptations of strength gain.

  2. Abstraction Mechanisms in the BETA Programming Language

    DEFF Research Database (Denmark)

    Kristensen, Bent Bruun; Madsen, Ole Lehrmann; Møller-Pedersen, Birger;

    1983-01-01

    The BETA programming language is developed as part of the BETA project. The purpose of this project is to develop concepts, constructs and tools in the field of programming and programming languages. BETA has been developed from 1975 on and the various stages of the language are documented in [BETA...... a]. The application area of BETA is programming of embedded as well as distributed computing systems. For this reason a major goal has been to develop constructs that may be efficiently implemented. Furthermore the BETA language is intended to have a few number of basic but general constructs...... to SMALLTALK, BETA is a language in the ALGOL 60 ([ALGOL]) family. SIMULA 67 is a system description and a programming language. The DELTA language ([DELTA]) is a system description language only, allowing description of full concurrency, continuous change and component interaction, developed from a SIMULA...

  3. In trangenic rice, alpha- and beta-tubulin regulatory sequences control GUS amount and distribution through intron mediated enhancement and intron dependent spatial expression.

    Science.gov (United States)

    Gianì, Silvia; Altana, Andrea; Campanoni, Prisca; Morello, Laura; Breviario, Diego

    2009-04-01

    The genomic upstream sequence of the rice tubulin gene OsTub6 has been cloned, sequenced and characterized. The 5'UTR sequence is interrupted by a 446 bp long leader intron. This feature is shared with two other rice beta-tubulin genes (OsTub4 and OsTub1) that, together with OsTub6, group in the same clade in the evolutionary phylogenetic tree of plant beta-tubulins. Similarly to OsTub4, the leader intron of OsTub6 is capable of sustaining intron mediated enhancement (IME) of gene expression, in transient expression assays. A general picture is drawn for three rice alpha-tubulin and two rice beta-tubulin genes in which the first intron of the coding sequence for the formers and the intron present in the 5'UTR for the latters, are important elements for controlling gene expression. We used OsTua2:GUS, OsTua3:GUS, OsTub4:GUS and OsTub6:GUS chimeric constructs to investigate the in vivo pattern of beta-glucuronidase (GUS) expression in transgenic rice plants. The influence of the regulatory introns on expression patterns was evaluated for two of them, OsTua2 and OsTub4. We have thus characterized distinct patterns of expression attributable to each tubulin isotype and we have shown that the presence of the regulatory intron can greatly influence both the amount and the actual site of expression. We propose the term Intron Dependent Spatial Expression (IDSE) to highlight this latter effect. PMID:18668337

  4. Beta-N-methylamino-L-alanine (BMAA) and isomers : distribution in different food web compartments of Thau lagoon, French Mediterranean Sea

    OpenAIRE

    Reveillon, D.; Abadie, E; Sechet, V.; Masseret, Estelle; Hess, P.; Amzil, Z.

    2015-01-01

    The neurotoxin BMAA (beta-N-methylamino-L-alanine) and its isomer DAB (2,4-diaminobutyric acid) have been detected in seafood worldwide, including in Thau lagoon (French Mediterranean Sea). A cluster of amyotrophic lateral sclerosis (ALS), a neurodegenerative disease associated with BMAA, has also been observed in this region. Mussels, periphyton (i.e. biofilms attached to mussels) and plankton were sampled between July 2013 and October 2014, and analyzed using HILIC-MS/MS. BMAA, DAB and AEG ...

  5. Histochemical studies on genetical control of hormonal enzyme inducibility in the mouse. III. Beta-glucuronidase distribution pattern of epididymis in different genotypes

    DEFF Research Database (Denmark)

    Blecher, S R; Kirkeby, S

    1979-01-01

    correlated with previous data for alpha-naphthyl acetate esterase. Differences between sites of granular and diffuse reaction product for these two enzymes are recorded. Possible interpretations of these findings in terms of intracellular localization of enzymes are discussed. Studies on different strains...... reveal regular differences in histochemical organization between mice of various genotypes. Histochemical data which imply androgen inducibility of beta-glucuronidase in mouse epididymis are preliminary noted....

  6. Effect of Sertraline on Current-Source Distribution of the High Beta Frequency Band: Analysis of Electroencephalography under Audiovisual Erotic Stimuli in Healthy, Right-Handed Males

    OpenAIRE

    Lee, Seung Hyun; Hyun, Jae Seog; Kwon, Oh-Young

    2010-01-01

    Purpose The purpose of this study was to examine the cerebral changes in high beta frequency oscillations (22-30 Hz) induced by sertraline and by audiovisual erotic stimuli in healthy adult males. Materials and Methods Scalp electroencephalographies (EEGs) were conducted twice in 11 healthy, right-handed males, once before sertraline intake and again 4 hours thereafter. The EEGs included four sessions recorded sequentially while the subjects were resting, watching a music video, resting, and ...

  7. Powder processing for the fabrication of Si3N4 ceramics. 1: Influence of spray-dried granule strength on pore size distribution in green compacts

    International Nuclear Information System (INIS)

    The effect of spray-dried granule strength on the microstructure of green compacts obtained by isostatic pressing was quantitatively analyzed. The fracture strength of single granules of Si3N4 powder made with ultrafine Al2O3 and Y2O3 powders was measured directly by diametral compression. It was found that fracture strength increased notably with the increasing relative density of the granule and the decreasing size of agglomerates in suspension before spray-drying. Even when green bodies were prepared at an isostatic pressure of 200 MPa, intergranular pores, which negatively affected densification of the sintered bodies, occurred between unfractured granules. The volume and size of these pores in the green compacts increased with the increasing fracture strength of the granules. In the case of closely packed granules, an isostatic pressure of 800 MPa was required to completely collapse the intergranular pores. A simple equation was derived to calculate the isostatic pressure necessary for complete collapse of intergranular pores in the green compacts, and it was determined that granule strength must be kept as low as possible to obtain uniform green compacts

  8. Reliability for Beta Models

    OpenAIRE

    Nadarajah, Saralees

    2002-01-01

    In the area of stress-strength models there has been a large amount of work as regards estimation of the reliability R = Pr(X2 < X1 ) when X1 and X2 are independent random variables belonging to the same univariate family of distributions. The algebraic form for R = Pr(X2 < X1 ) has been worked out for the majority of the well-known distributions including Normal, uniform, exponential, gamma, weibull and pareto. However, there are still many other distributions for which th...

  9. C3 polymorphism in beta-thalassemia.

    Science.gov (United States)

    Germenis, A; Kalantzi, M; Karamerou, A; Politi, C; Fertakis, A

    1984-01-01

    The distribution of phenotypes and gene frequencies of the third component of complement (C3) were studied in 106 beta-thalassemic patients and in 112 carriers of the beta-thalassemia trait. A statistically significant association was found between the C3F gene and homozygous beta-thalassemia. It can be suggested that this association may be related with the high incidence of infections encountered in these patients. PMID:6419525

  10. Catalytic conversion of chloromethane to methanol and dimethyl ether over two catalytic beds: a study of acid strength

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, D.R.; Leite, T.C.M.; Mota, C.J.A. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Quimica], e-mail: cmota@iq.ufrj.br

    2010-07-15

    The catalytic hydrolysis of chloromethane to methanol and dimethyl ether (DME) was studied over metal-exchanged Beta and Mordenite zeolites, acidic MCM-22 and SAPO-5. The use of a second catalytic bed with HZSM-5 zeolite increased the selectivity to DME, due to methanol dehydration on the acid sites. The effect was more significant on catalysts presenting medium and weak acid site distribution, showing that dehydration of methanol to DME is accomplished over sites of higher acid strength. (author)

  11. RAVEN Beta Release

    Energy Technology Data Exchange (ETDEWEB)

    Rabiti, Cristian [Idaho National Lab. (INL), Idaho Falls, ID (United States); Alfonsi, Andrea [Idaho National Lab. (INL), Idaho Falls, ID (United States); Cogliati, Joshua Joseph [Idaho National Lab. (INL), Idaho Falls, ID (United States); Mandelli, Diego [Idaho National Lab. (INL), Idaho Falls, ID (United States); Kinoshita, Robert Arthur [Idaho National Lab. (INL), Idaho Falls, ID (United States); Wang, Congjian [Idaho National Lab. (INL), Idaho Falls, ID (United States); Maljovec, Daniel Patrick [Idaho National Lab. (INL), Idaho Falls, ID (United States); Talbot, Paul William [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-02-01

    This documents the release of the Risk Analysis Virtual Environment (RAVEN) code. A description of the RAVEN code is provided, and discussion of the release process for the M2LW-16IN0704045 milestone. The RAVEN code is a generic software framework to perform parametric and probabilistic analysis based on the response of complex system codes. RAVEN is capable of investigating the system response as well as the input space using Monte Carlo, Grid, or Latin Hyper Cube sampling schemes, but its strength is focused toward system feature discovery, such as limit surfaces, separating regions of the input space leading to system failure, using dynamic supervised learning techniques. RAVEN has now increased in maturity enough for the Beta 1.0 release.

  12. RAVEN Beta Release

    International Nuclear Information System (INIS)

    This documents the release of the Risk Analysis Virtual Environment (RAVEN) code. A description of the RAVEN code is provided, and discussion of the release process for the M2LW-16IN0704045 milestone. The RAVEN code is a generic software framework to perform parametric and probabilistic analysis based on the response of complex system codes. RAVEN is capable of investigating the system response as well as the input space using Monte Carlo, Grid, or Latin Hyper Cube sampling schemes, but its strength is focused toward system feature discovery, such as limit surfaces, separating regions of the input space leading to system failure, using dynamic supervised learning techniques. RAVEN has now increased in maturity enough for the Beta 1.0 release.

  13. Effects of deformation on the beta-decay patterns of light even-even and odd-mass Hg and Pt isotopes

    CERN Document Server

    Boillos, J M

    2015-01-01

    Bulk and decay properties, including deformation energy curves, charge mean square radii, Gamow-Teller (GT) strength distributions, and beta-decay half-lives, are studied in neutron-deficient even-even and odd-A Hg and Pt isotopes. The nuclear structure is described microscopically from deformed quasiparticle random-phase approximation calculations with residual interactions in both particle-hole and particle-particle channels, performed on top of a self-consistent deformed quasiparticle Skyrme Hartree-Fock basis. The observed sensitivity of the, not yet measured, GT strength distributions to deformation is proposed as an additional complementary signature of the nuclear shape. The $\\beta$-decay half-lives resulting from these distributions are compared to experiment to demonstrate the ability of the method.

  14. Effect of 17 beta-oestradiol on growth curves and flow cytometric DNA distribution of two human breast carcinomas grown in nude mice

    DEFF Research Database (Denmark)

    Brünner, N; Spang-Thomsen, M; Vindeløv, L;

    1983-01-01

    The effect of 17 beta-oestradiol on a "receptor positive" and on a "receptor negative" human breast carcinoma grown in nude mice was studied. Experimental growth data were used to determine the effect on tumour growth. Flow cytometric DNA analysis (FCM) performed on tumour tissue obtained by...... sequential fine-needle aspirations was used to estimate the effect on the cell cycle. In the receptor-positive breast carcinoma, oestradiol induced complete tumour regression and characteristic cell cycle changes. In the receptor-negative breast carcinoma, no changes in tumour growth and cell cycle...

  15. Computational methods for analyzing the transmission characteristics of a beta particle magnetic analysis system

    Science.gov (United States)

    Singh, J. J.

    1979-01-01

    Computational methods were developed to study the trajectories of beta particles (positrons) through a magnetic analysis system as a function of the spatial distribution of the radionuclides in the beta source, size and shape of the source collimator, and the strength of the analyzer magnetic field. On the basis of these methods, the particle flux, their energy spectrum, and source-to-target transit times have been calculated for Na-22 positrons as a function of the analyzer magnetic field and the size and location of the target. These data are in studies requiring parallel beams of positrons of uniform energy such as measurement of the moisture distribution in composite materials. Computer programs for obtaining various trajectories are included.

  16. Bivariate distributions in statistical spectroscopy studies. Pt. 4. Interacting particle Gamow-Teller strength densities and β-decay rate of fp-shell nuclei for presupernova stars

    International Nuclear Information System (INIS)

    A method to calculate temperature dependent β-decay rates is developed by writing the expression for the rates explicitly in terms of bivariate GT strength densities (IHO(GT)) for a given hamiltonian H = h + V and state densities of the parent nucleus besides having the usual phase space factors. The theory developed in the preceding paper (III) for constructing NIP strength densities is applied for generating IhO(GT) and then IHO(GT) is constructed using the bivariate convolution form IHO(GT) ΣSIh,SO(GT) x ρV,SO(GT);BIV-G. The spreading bivariate Gaussian ρVO(GT);BIV-G, for fp-shell nuclei, is constructed by assuming that the marginal centroids are zero, the marginal variances are same as the corresponding state density variances and fixing the bivariate correlation coefficient anti ζ using experimental β-decay half lifes. With the deduced values of anti ζ anti ζ ∼ 0.67, β-decay rates for 61,62Fe and 62-64Co isotopes are calculated at presupernova matter densities ρ = 107-109 gm/cc, temperatures T = (3 - 5) x 109 K and electron fractions Ye = 0.43 - 0.5. The convolution form for IHO(GT) led to a simple expression for calculating GT non-energy weighted sum rule strength and it describes (within 10%) the shell model results of fp-shell nuclei. (orig.)

  17. Gamow-Teller strength functions and neutrino problems

    International Nuclear Information System (INIS)

    A quantitative understanding of spin strengths in nuclei is of vital importance in studies of nuclear double beta decay and in solar neutrino spectroscopy. The current status of these problems is outlined

  18. A stochastic prediction of in situ stress magnitudes from the distributions of rock strength and breakout width at IODP Hole C0002A in Nankai accretionary prism, SW Japan

    Science.gov (United States)

    Song, Insun; Chang, Chandong; Lee, Hikweon

    2015-04-01

    Most continuum theories in rock mechanics are based on a postulate of existence of a representative elementary volume (REV), over which a single number is chosen as an effective rock property. Such deterministic prediction of rock property without clear account of microstructural randomness over the REV excludes a rational discussion on risk assessment and uncertainty analysis. If the rock property is scale-dependent or severely heterogeneous, its distribution may provide more valuable information than its average does. Borehole wall images and sonic logging data obtained from IODP Hole C0002A near the Nankai Trough show a wide distribution of breakout widths and rock strengths even at a short interval of depth. The small-scale but frequent variation in breakout width in a short section of borehole wall is due to heterogeneous rock strength rather than a correspondingly frequent change in far-field stress. In this paper we consider the distribution of rock strengths and breakout widths in a given length of wellbore, which is large enough to analyze the logging data in a statistical manner but small enough to make sure that the far-field stresses are to be uniform, in order to determine the magnitudes of the stresses. Assuming the normal distribution of uniaxial compressive strength (UCS), which is estimated empirically from sonic velocity logs (Chang et al., 2006, JPSE; 2010, G3), we calculated the probability distribution of breakout width for given sets of the maximum and the minimum horizontal principal stresses (SHmax and Shmin, respectively) for every 20m depth interval. The same procedure was repeated for various combinations of the two horizontal principal stress magnitudes. Then the objective function with two variables, SHmax and Shmin, was obtained from the total misfits between the observed and the calculated occurrence distributions of breakout width. Finally we were able to determine the best solution of SHmax and Shmin with the minimum total misfit

  19. Beta cell count instead of beta cell mass to assess and localize growth in beta cell population following pancreatic duct ligation in mice.

    Directory of Open Access Journals (Sweden)

    Marie Chintinne

    Full Text Available BACKGROUND: Pancreatic-tail duct ligation (PDL in adult rodents has been reported to induce beta cell generation and increase beta cell mass but increases in beta cell number have not been demonstrated. This study examines whether PDL increases beta cell number and whether this is caused by neogenesis of small clusters and/or their growth to larger aggregates. METHODOLOGY: Total beta cell number and its distribution over small (100 µm clusters was determined in pancreatic tails of 10-week-old mice, 2 weeks after PDL or sham. PRINCIPAL FINDINGS: PDL increased total beta cell mass but not total beta cell number. It induced neogenesis of small beta cell clusters (2.2-fold higher number which contained a higher percent proliferating beta cells (1.9% Ki67+cells than sham tails (<0.2%; their higher beta cell number represented <5% of total beta cell number and was associated with a similar increase in alpha cell number. It is unknown whether the regenerative process is causally related to the inflammatory infiltration in PDL-tails. Human pancreases with inflammatory infiltration also exhibited activation of proliferation in small beta cell clusters. CONCLUSIONS/SIGNIFICANCE: The PDL model illustrates the advantage of direct beta cell counts over beta cell mass measurements when assessing and localizing beta cell regeneration in the pancreas. It demonstrates the ability of the adult mouse pancreas for neogenesis of small beta cell clusters with activated beta cell proliferation. Further studies should investigate conditions under which neoformed small beta cell clusters grow to larger aggregates and hence to higher total beta cell numbers.

  20. N-cadherin mediated distribution of beta-catenin alters MAP kinase and BMP-2 signaling on chondrogenesis-related gene expression.

    Science.gov (United States)

    Modarresi, Rozbeh; Lafond, Toulouse; Roman-Blas, Jorge A; Danielson, Keith G; Tuan, Rocky S; Seghatoleslami, M Reza

    2005-05-01

    We have examined the effect of calcium-dependent adhesion, mediated by N-cadherin, on cell signaling during chondrogenesis of multipotential embryonic mouse C3H10T1/2 cells. The activity of chondrogenic genes, type II collagen, aggrecan, and Sox9 were examined in monolayer (non-chondrogenic), and micromass (chondrogenic) cultures of parental C3H10T1/2 cells and altered C3H10T1/2 cell lines that express a dominant negative form of N-cadherin (delta390-T1/2) or overexpress normal N-cadherin (MNCD2-T1/2). Our findings show that missexpression or inhibition of N-cadherin in C3H10T1/2 cells results in temporal and spatial changes in expression of the chondrogenic genes Sox9, aggrecan, and collagen type II. We have also analyzed activity of the serum response factor (SRF), a nuclear target of MAP kinase signaling implicated in chondrogenesis. In semi-confluent monolayer cultures (minimum cell-cell contact) of C3H10T1/2, MNCD2-T1/2, or delta390-T1/2 cells, there was no significant change in the pattern of MAP kinase or bone morphogenetic protein-2 (BMP-2) regulation of SRF. However, in micromass cultures, the effect of MAP kinase and BMP-2 on SRF activity was proportional to the nuclear localization of beta-catenin, a Wnt stabilized cytoplasmic factor that can associate with lymphoid enhancer-binding factor (LEF) to serve as a transcription factor. Our findings suggest that the extent of adherens junction formation mediated by N-cadherin can modulate the potential Wnt-induced nuclear activity of beta-catenin. PMID:15723280

  1. Determination of the electromagnetic dipole strength distribution in medium-heavy atomic nuclei by means of nuclear resonance fluorescence; Bestimmung der elektromagnetischen Dipolstaerkeverteilung in mittelschweren Atomkernen mittels Kernresonanzfluoreszenz

    Energy Technology Data Exchange (ETDEWEB)

    Massarczyk, Ralph Jens

    2011-01-17

    During the last hundred years several models were developed to describe the configuration of nuclei. These models have to make predictions, which should be comparable with experiments. As a standard type of experiment the nuclear resonance fluorescence was established. A nucleus is excited by irradiation with photons. By emitting one or more photons the nucleus decays back to the ground state. With this method it is possible to measure energy levels and to determine the strength of their excitation. A continuum of unresolved peaks gives additional strength. The existing setup at the linear electron accelerator ELBE of the Forschungszentrum Dresden-Rossendorf uses bremsstrahlung, produced as a secondary beam in a thin Niobium foil. During the years 2008/09 experiments on the nuclei of {sup 86}Kr and {sup 136}Ba took place there. In this work they will be analyzed. Photon flux and efficiency determination have been done as well as simulations on detector response and non-nuclear scattered background events. For this purpose the GEANT4 package was used. Finally the resulting cross sections were corrected for branching and feeding.

  2. Strength dynamics of weighted evolving networks

    Institute of Scientific and Technical Information of China (English)

    Wu Jian-Jun; Gao Zi-You; Sun Hui-Jun

    2007-01-01

    In this paper, a simple model for the strength dynamics of weighted evolving networks is proposed to characterize the weighted networks. By considering the congestion effects, this approach can yield power law strength distribution appeared on the many real weighted networks, such as traffic networks, internet networks. Besides, the relationship between strength and degree is given. Numerical simulations indicate that the strength distribution is strongly related to the strength dynamics decline. The model also provides us with a better description of the real weighted networks.

  3. [Survey of the antibiotic sensitivity of Pseudomonas aeruginosa in France and the distribution of beta-lactam resistance mechanisms: the GERPB 1999 study].

    Science.gov (United States)

    Cavallo, J D; Leblanc, F; Fabre, R; Fourticq-Esqueöute, A

    2001-09-01

    A prospective survey was carried out in october 1999 in 15 french teaching hospitals. Average susceptibility rates, determined by minimal inhibitory concentrations, for the 738 non-repetitive strains of P. aeruginosa isolated were: ticarcillin, 58%, ticarcillin + clavulanic acid, 56%, piperacillin, 73%, piperacillin + tazobactam, 82%, ceftazidime, 76%, cefepime, 53%, cefpirome, 36%, aztreonam, 58%, imipenem, 81%, amikacin, 62%, tobramycine, 71% and, ciprofloxacin, 60%. Among the 75% serotypable strains, the most frequent serotypes were: O:6 (15.3%), O:11 (14.5%), O:1 (10.4%), O:3 (7.9%), O:4 (6.1%) and O:12 (6.1%). The serotype O:12 was the most resistant to antibiotics. Forty-two percent of the strains were resistant or presented an intermediate susceptibility to ticarcillin. Mechanisms were as follow: 14.5% non enzymatic mechanism, 12.5% overproduction of the constitutive cephalosporinase, 7.1% transferable betalactamase and, 6.9% combination of these mechanisms. Among the 67 transferable betalactamases: 48 (71.6%) were PSE-1, 12 (19.4%) TEM-2 and 6 (7.5%) oxacillinases. One extended spectrum betalactamase was characterized. Among the cephalosporines tested, cefepime was less affected by the overproduction of constitutive cephalosporinase. Ceftazidime, remained the best cephalosporin except against the strains overexpressing the chromosomal type 1 beta-lactamase. Resistance to tobramycin was mainly due to enzymatic mechanisms with a high level of resistance. Decreased susceptibility was more frequent for amikacin than for tobramycin. This was probably related with non enzymatic mechanisms. PMID:11642015

  4. A modeling study on the controlling factors of seismic source distribution and their strength index——Practical analyses of the seismic environmental factors of the Honghe fault

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A model, in which various seismic environmental factors areinvolved, has been developed in the paper on the bases of relevant data. The environmental factors include the crust structure, lithological conditions, fault plan attitude, the crust stress state, pore-fluid pressure and geothermal conditions, etc. The effect of each of the factors on the tectonic movement energy index has been analyzed. The model calculation results indicate that shear fractu-re energy of a fault generally increases with depth; it reached a peak value at a certain depth, then turns gradually attenuated. Of all the factors, the effects of pore-fluid pressure and geothermal conditions on the energy index are of prominence. High pore-fluid pressure and high temperature circumstance may result in decline of the peak value of the shear fracture energy curve, making the depths of the peak value and of the bell-waist value deepened. Such effects restrict strong seismic events, but suitable for micro-seismic activity and/or fault creep. The lower limit of focal depth under such an environment is relatively deep. Contrarily, low pore-fluid pressure and low geothermal temperature circumstance result in increase of the peak value of the shear fracture energy curve, and the curve becoming steep. The later circumstance is favorable to the formation of locked segment where possesses high strength and high-energy accumulation. If these two kind of segments are arranged interactively along a fault zone, such arrangement would boost the energy transition among the segments, forming mechanical circumstance of energy highly accumulated in one segment with adjacent segment(s) less-locked. Such contrast of the strength and energy would provide conditions for strong earthquakes with high stress drop. An analysis of the northwest seg-ment of the Honghe fault has provided some evidence for the modeling results.

  5. Shape effects in the vicinity of the Z=82 line: study of the $\\beta$-decay of $^{182,184,186}$Hg

    CERN Multimedia

    This proposal is aimed at the study of the $\\beta$-decay of the neutron-­deficient $^{182,184,186}$Hg nuclei using the total absorption technique. Recent theoretical results show that, from measurements of the Gamow-­Teller strength distribution, the shapes of the ground states of the decaying Hg nuclei can be inferred. This study offers an independent way to study the phenomenon of shape coexistence in a region of particular interest.

  6. Beta-delayed proton emission in neutron-deficient lanthanide isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Wilmarth, P.A.

    1988-09-30

    Forty-two ..beta..-delayed proton precursors with 56less than or equal toZless than or equal to71 and 63less than or equal toNless than or equal to83 were produced in heavy-ion reactions at the Lawrence Berkeley Laboratory SuperHILAC and their radioactive decay properties studied at the on-line mass separation facility OASIS. Twenty-five isotopes and eight delayed proton branches were identified for the first time. Delayed proton energy spectra and proton coincident ..gamma..-ray and x-ray spectra were measured for all precursors. In a few cases, proton branching ratios were also determined. The precursor mass numbers were determined by the separator, while the proton coincident x-ray energies provided unambiguous Z identifications. The proton coincident ..gamma..-ray intensities were used to extract final state branching ratios. Proton emission from ground and isomeric states was observed in many cases. The majority of the delayed proton spectra exhibited the smooth bell-shaped distribution expected for heavy mass precursors. The experimental results were compared to statistical model calculations using standard parameter sets. Calculations using Nilsson model/RPA ..beta..-strength functions were found to reproduce the spectral shapes and branching ratios better than calculations using either constant or gross theory ..beta..-strength functions. Precursor half-life predictions from the Nilsson model/RPA ..beta..-strength functions were also in better agreement with the measured half-lives than were gross theory predictions. The ratios of positron coincident proton intensities to total proton intensities were used to determine Q/sub EC/-B/sub p/ values for several precursors near N=82. The statistical model calculations were not able to reproduce the experimental results for N=81 precursors. 154 refs., 82 figs., 19 tabs.

  7. The Beta-MANOVA Ensemble with General Covariance

    OpenAIRE

    Dubbs, Alexander; Edelman, Alan

    2013-01-01

    We find the joint generalized singular value distribution and largest generalized singular value distributions of the $\\beta$-MANOVA ensemble with positive diagonal covariance, which is general. This has been done for the continuous $\\beta > 0$ case for identity covariance (in eigenvalue form), and by setting the covariance to $I$ in our model we get another version. For the diagonal covariance case, it has only been done for $\\beta = 1,2,4$ cases (real, complex, and quaternion matrix entries...

  8. Characterization of footprint-scale surface soil moisture variability using Gaussian and beta distribution functions during the Southern Great Plains 1997 (SGP97) hydrology experiment

    OpenAIRE

    Ryu, Dongryeol; Famiglietti, James S.

    2005-01-01

    The behavior of satellite footprint-scale surface soil moisture probability density functions (PDF) was analyzed using 50-km-scale samples taken from soil moisture images collected during the Southern Great Plains 1997 (SGP97) hydrology experiment. Under the observed wetness conditions, soil moisture variability generally peaked in the midrange of mean soil moisture content and decreased toward the wet and dry ends, while in the midrange it was more widely distributed. High variability in the...

  9. Levered and unlevered Beta

    OpenAIRE

    Fernandez, Pablo

    2003-01-01

    We prove that in a world without leverage cost the relationship between the levered beta ( L) and the unlevered beta ( u) is the No-costs-of-leverage formula: L = u + ( u - d) D (1 - T) / E. We also analyze 6 alternative valuation theories proposed in the literature to estimate the relationship between the levered beta and the unlevered beta (Harris and Pringle (1985), Modigliani and Miller (1963), Damodaran (1994), Myers (1974), Miles and Ezzell (1980), and practitioners) and prove that all ...

  10. Neutron-gamma competition for $\\beta$-delayed neutron emission

    CERN Document Server

    Mumpower, Matthew; Moller, Peter

    2016-01-01

    We present a coupled Quasi-particle Random Phase Approximation and Hauser-Feshbach (QRPA+HF) model for calculating delayed particle emission. This approach uses microscopic nuclear structure information which starts with Gamow-Teller strength distributions in the daughter nucleus, and then follows the statistical decay until the initial available excitation energy is exhausted. Explicitly included at each particle emission stage is $\\gamma$-ray competition. We explore this model in the context of neutron emission of neutron-rich nuclei and find that neutron-gamma competition can lead to both increases and decreases in neutron emission probabilities, depending on the system considered. A second consequence of this formalism is a prediction of more neutrons on average being emitted after $\\beta$-decay for nuclei near the neutron dripline compared to models that do not consider the statistical decay.

  11. Betting Against Beta

    DEFF Research Database (Denmark)

    Frazzini, Andrea; Heje Pedersen, Lasse

    .S. equities, 20 international equity markets, Treasury bonds, corporate bonds, and futures; (2) A betting-against-beta (BAB) factor, which is long leveraged low beta assets and short high-beta assets, produces significant positive risk-adjusted returns; (3) When funding constraints tighten, the return of the...

  12. Forward-Looking Betas

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Jacobs, Kris; Vainberg, Gregory

    Few issues are more important for finance practice than the computation of market betas. Existing approaches compute market betas using historical data. While these approaches differ in terms of statistical sophistication and the modeling of the time-variation in the betas, they are all backward-...

  13. Regional differences in islet distribution in the human pancreas--preferential beta-cell loss in the head region in patients with type 2 diabetes.

    Directory of Open Access Journals (Sweden)

    Xiaojun Wang

    Full Text Available While regional heterogeneity in islet distribution has been well studied in rodents, less is known about human pancreatic histology. To fill gaps in our understanding, regional differences in the adult human pancreas were quantitatively analyzed including the pathogenesis of type 2 diabetes (T2D. Cadaveric pancreas specimens were collected from the head, body and tail regions of each donor, including subjects with no history of diabetes or pancreatic diseases (n = 23 as well as patients with T2D (n = 12. The study further included individuals from whom islets were isolated (n = 7 to study islet yield and function in a clinical setting of islet transplantation. The whole pancreatic sections were examined using an innovative large-scale image capture and unbiased detailed quantitative analyses of the characteristics of islets from each individual (architecture, size, shape and distribution. Islet distribution/density is similar between the head and body regions, but is >2-fold higher in the tail region. In contrast to rodents, islet cellular composition and architecture were similar throughout the pancreas and there was no difference in glucose-stimulated insulin secretion in islets isolated from different regions of the pancreas. Further studies revealed preferential loss of large islets in the head region in patients with T2D. The present study has demonstrated distinct characteristics of the human pancreas, which should provide a baseline for the future studies integrating existing research in the field and helping to advance bi-directional research between humans and preclinical models.

  14. Acoustical study of the spatial distribution of plankton on Georges Bank and the relationship between volume backscattering strength and the taxonomic composition of the plankton

    Science.gov (United States)

    Wiebe, P. H.; Mountain, D. G.; Stanton, T. K.; Greene, C. H.; Lough, G.; Kaartvedt, S.; Dawson, J.; Copley, N.

    significant only for pteropods and euphausiid larvae. The abundances of copepods, chaetognaths, fish larvae, and amphipods were not significantly correlated with volume scattering. When taxon-specific model predictions of acoustic backscattering cross-section, developed by Stanton et al. ( ICES Journal of Marine Science, 51(1994) 505-512), were used with field collected individual size and abundance data to predict measured volume backscattering data, good agreement was found between observed and predicted volume backscattering strengths.

  15. ASSESSMENTOF BETA PARTICLE FLUX FROM SURFACE CONTAMINATION AS A RELATIVE INDICATOR FOR RADIONUCLIDE DISTRIBUTION ON EXTERNAL SURFACES OF A MULTI-STORY BUILDING IN PRIPYAT

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, E.

    2009-11-17

    How would we recover if a Radiological Dispersion Device (e.g., dirty bomb) or Improvised Nuclear Device were to detonate in a large city? In order to assess the feasibility of remediation following such an event, several issues would have to be considered, including the levels and characteristics of the radioactive contamination, the availability of the required resources to accomplish decontamination, and the planned future use of the city's structures and buildings. Presently little is known about the distribution, redistribution, and migration of radionuclides in an urban environment. However, Pripyat, a city substantially contaminated by the Chernobyl Nuclear Power Plant accident, may provide some answers. The main objective of this study was to determine the radionuclide distribution on a Pripyat multi-story building, which had not been previously decontaminated and therefore could reflect the initial fallout and its further natural redistribution on external surfaces. The 7-story building selected was surveyed from the ground floor to the roof on horizontal and vertical surfaces along seven ground-to-roof transections. Some of the results from this study indicate that the upper floors of the building had higher contamination levels than the lower floors. The authors consequently recommend that existing decontamination procedures for tall structures be re-examined and modified accordingly.

  16. Assessment of beta particle flux from surface contamination as a relative indicator for radionuclide distribution on external surfaces of a multistory building in Pripyat.

    Science.gov (United States)

    Farfán, Eduardo B; Gaschak, Sergii P; Maksymenko, Andriy M; Jannik, G Tim; Marra, James C; Bondarkov, Mikhail D; Donnelly, Elizabeth H

    2011-02-01

    Several issues should be considered when assessing the feasibility of remediation following the detonation of a radiological dispersion device (e.g., dirty bomb) or improvised nuclear device in a large city. These issues include the levels and characteristics of the radioactive contamination, the availability of resources required for decontamination, and the planned future use of the city's structures and buildings. Presently, little is known about the distribution, redistribution, and migration of radionuclides in an urban environment. However, Pripyat, a city substantially contaminated by the Chernobyl Nuclear Power Plant accident in April 1986, may provide some answers. The main objective of this study was to determine the radionuclide distribution on a Pripyat multistory building that had not been decontaminated and, therefore, could reflect the initial fallout and its further natural redistribution on external surfaces over 23 y. The seven-story building selected was surveyed from the ground floor to the roof on horizontal and vertical surfaces along seven ground-to-roof transections. Some results from this study indicate that the upper floors of the building had higher contamination levels than the lower floors. Consequently, the authors recommend that thorough decontamination should be considered for all the floors of tall buildings (not just lower floors). PMID:21399438

  17. Distribution of alpha and beta thalassaemia genotypes in childbearing age people in Shanwei%汕尾市育龄人群中α、β地中海贫血基因型的分布调查

    Institute of Scientific and Technical Information of China (English)

    孙妙婷; 董响波; 黄琦玲

    2014-01-01

    objective To understand the distribution of alpha and beta thalassaemia genotypes in childbearing age people in Shanwei.Methods Pregnant woment and their spouses 1200 cases were chosen from the hospitals of each area from January 1st to December 1st 2013 as study objects using cluster sampling method.Alpha beta thalassaemia were investigated respectively.Results Among the 1200 blood samples,6 kinds of alpha thalassaemia genotypes were detected,with a total of 62 cases,63 alleles.The alpha thalassaemia gene carrying rate was 5.25% (63/1200).The genotype composition:31-a3.7/aa,49.21% of the total; 18-aSEA/aa,28.57% of the total; 7-a4.2/aa,11.11% of the total; 2-aTHAI/aa,3.17% of the total; 3--SEA/--SEA,4.76% of the total; 2-aCSa/aa,3.17% of the total.13 cases were detected with beta thalassemia gene,with a beta thalassemia gene carrying rate of 1.08%.There were five genetic types of beta thalassemia gene including IVS-2-654 (C → T) and-28 (A → G) (both accounted for 23.08%),CD41/42 (-TCTT) (30.77%),CD17 (A → T) (15.38%),and beta ECD26 (C → A) (7.69%).Conclusions The alpha thalassaemia gene carrying rate and beta thalassaemia carrying rate of Shanwei are relatively lower among the whole province.However,but the analysis of the data showed that the carrying rate was high,thalassaemia genes were carried mainly by people,most of which are natives,in regions with complex genetic background.%目的 了解汕尾市育龄人群中α、β地中海贫血基因型的分布情况.方法 采用整群抽样方法选择2013年1月1日至2013年12月31日各地区部分住院分娩和引产的孕产妇、配偶共计1200例作为研究对象,分别进行α-地中海贫血和β-地中海贫血调查.结果 在1200份血液标本中共计检测出6种α-地中海贫血基因型,共计62例,63个等位基因,α-地中海贫血基因携带率为5.25%(63/1200).其基因型构成比:-a3.7/aa 31个,占总数的49.21%;-aSEA/aa 18个,占总数的28.57

  18. Fission product migration in intact fuel rods. S176 experiments 1-5: Gamma spectrometric and beta autoradiography results on radial fission product distribution

    International Nuclear Information System (INIS)

    This report is the third of a group which present the results obtained during the first 5 experiments in the S176 series of irradiation experiments. The aim of this series is to provide information on the distribution of fission products in intact irradiated fuel rods, both within the UO2, fuel and on the inside of the Zircaloy clad. Fuel rods, previously irradiated to appreciable burnups in the Aagesta R3 reactor, after cooling, are reirradiated in the Studsvik R2 test reactor for short periods to build up significant inventories of short-lived fission products of interest. The irradiation conditions are well defined. Examination of sections of fuel and clad within a short time after removal from the reactor is performed by means of high-resolution Ge(Li) gamma spectrometry. The fuel sections are also examined metallographically to determine fuel structure, and by β autoradiography

  19. Beta-globin gene haplotypes among cameroonians and review of the global distribution: is there a case for a single sickle mutation origin in Africa?

    Science.gov (United States)

    Bitoungui, Valentina J Ngo; Pule, Gift D; Hanchard, Neil; Ngogang, Jeanne; Wonkam, Ambroise

    2015-03-01

    Studies of hemoglobin S haplotypes in African subpopulations have potential implications for patient care and our understanding of genetic factors that have shaped the prevalence of sickle cell disease (SCD). We evaluated HBB gene cluster haplotypes in SCD patients from Cameroon, and reviewed the literature for a global distribution. We reviewed medical records to obtain pertinent socio-demographic and clinical features for 610 Cameroonian SCD patients, including hemoglobin electrophoresis and full blood counts. RFLP-PCR was used to determine the HBB gene haplotype on 1082 chromosomes. A systematic review of the current literature was undertaken to catalogue HBB haplotype frequencies in SCD populations around the world. Benin (74%; n = 799) and Cameroon (19%; n = 207) were the most prevalent haplotypes observed among Cameroonian patients. There was no significant association between HBB haplotypes and clinical life events, anthropometric measures, hematological parameters, or fetal hemoglobin (HbF) levels. The literature review of the global haplotype distributions was consistent with known historical migrations of the people of Africa. Previously reported data from Sudan showed a distinctly unusual pattern; all four classical haplotypes were reported, with an exceptionally high proportion of the Senegal, Cameroon, and atypical haplotypes. We did not observe any significant associations between HBB haplotype and SCD disease course in this cohort. Taken together, the data from Cameroon and from the wider literature suggest that a careful reassessment of African HBB haplotypes may shed further light on the evolutionary dynamics of the sickle allele, which could suggest a single origin of the sickle mutation. PMID:25748438

  20. A physical model to describe the distribution of adhesion strength in MEMS, or why one MEMS device sticks and another ‘identical’ one does not

    International Nuclear Information System (INIS)

    In this paper a model is presented that describes the distribution of adhesion values typically experimentally observed for different MEMS devices that have been fabricated in the same way. This spread is attributed to the fact that different devices differ in the details of their surface roughness, even if these surface roughnesses are modeled as coming from the same ‘parent’ stochastic process. Using Monte Carlo simulations, the effect of surface roughness and relative humidity has been evaluated in detail, both on the expected mean value of the surface interaction energy between the MEMS surfaces, and the expected spread on this value from device to device. By comparing the new model to existing literature reporting this experimentally observed spread, we have found excellent agreement between the experimental spread observed, and the spread calculated with the theoretical model using Monte Carlo simulations. This work paves the way to detailed adhesion failure predictive modeling. It may be used to assess the reliability of MEMS designs that rely on contacting surfaces for their operation, but have a limited restoring force available to separate the surfaces when in contact. (paper)

  1. Characterization of the papilionoid-Burkholderia interaction in the Fynbos biome: The diversity and distribution of beta-rhizobia nodulating Podalyria calyptrata (Fabaceae, Podalyrieae).

    Science.gov (United States)

    Lemaire, Benny; Van Cauwenberghe, Jannick; Verstraete, Brecht; Chimphango, Samson; Stirton, Charles; Honnay, Olivier; Smets, Erik; Sprent, Janet; James, Euan K; Muasya, A Muthama

    2016-02-01

    The South African Fynbos soils are renowned for nitrogen-fixing Burkholderia associated with diverse papilionoid legumes of the tribes Crotalarieae, Hypocalypteae, Indigofereae, Phaseoleae and Podalyrieae. However, despite numerous rhizobial studies in the region, the symbiotic diversity of Burkholderia has not been investigated in relation to a specific host legume and its geographical provenance. This study analyzed the diversity of nodulating strains of Burkholderia from the legume species Podalyria calyptrata. Diverse lineages were detected that proved to be closely related to Burkholderia taxa, originating from hosts in other legume tribes. By analyzing the genetic variation of chromosomal (recA) and nodulation (nodA) sequence data in relation to the sampling sites we assessed the geographical distribution patterns of the P. calyptrata symbionts. Although we found a degree of genetically differentiated rhizobial populations, a correlation between genetic (recA and nodA) and geographic distances among populations was not observed, suggesting high rates of dispersal and rhizobial colonization within Fynbos soils. PMID:26689612

  2. Beta-decay in odd-A and even-even proton-rich Kr isotopes

    CERN Document Server

    Sarriguren, P; Escuderos, A

    2001-01-01

    Beta-decay properties of proton-rich odd-A and even-even Krypton isotopes are studied in the framework of a deformed selfconsistent Hartree-Fock calculation with density-dependent Skyrme forces, including pairing correlations between like nucleons in BCS approximation. Residual spin-isospin interactions are consistently included in the particle-hole and particle-particle channels and treated in Quasiparticle Random Phase Approximation. The similarities and differences in the treatment of even-even and odd-A nuclei are stressed. Comparison to available experimental information is done for Gamow-Teller strength distributions, summed strengths, and half-lives. The dependence of these observables on deformation is particularly emphasized in a search for signatures of the shape of the parent nucleus.

  3. Sensitive behavior of 2{nu}{beta}{beta}-decay amplitude within QRPA and broken SU(4) symmetry in nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Rodin, Vadim A. [Institut fuer Theoretische Physik der Universitaet Tuebingen, Auf der Morgenstelle 14, D-72076 Tuebingen (Germany)]. E-mail: vadim.rodin@uni-tuebingen.de; Urin, Michael H. [Department of Theoretical Nuclear Physics, Moscow State Engineering and Physics Institute, 115409 Moscow (Russian Federation); Kernfysisch Versneller Institute, NL-9747AA Groningen (Netherlands); Faessler, Amand [Institut fuer Theoretische Physik der Universitaet Tuebingen, Auf der Morgenstelle 14, D-72076 Tuebingen (Germany)

    2005-01-24

    Making use of an identity transformation independent of a nuclear model, we represent the 2{nu}{beta}{beta}-amplitude as a sum of two terms. One term accounts for most of the sensitivity of the original 2{nu}{beta}{beta}-amplitude to gpp' for realistic gpp'{approx}1 (with gpp' being the ratio of the triplet and singlet p-p interaction strengths) and is determined by a specific energy-weighted sum rule. The sum rule depends only on the particle-particle residual interaction (being linear function of gpp' in the QRPA) and passes through zero at the point gpp'=1 where the Wigner SU(4) symmetry is restored in the p-p sector of the Hamiltonian. The second term in the decomposition of the 2{nu}{beta}{beta}-amplitude is demonstrated within the QRPA to be a much smoother function for the realistic values of gpp' than the original 2{nu}{beta}{beta}-amplitude. This term is mainly determined by the intensity of the spin-orbit interaction of the nuclear mean field. Thus, the analysis of the present work reveals the reasons for the sensitivity of the 2{nu}{beta}{beta}-amplitude to different components of the nuclear Hamiltonian and thereby can help in constraining nuclear model uncertainties in calculations of the amplitude.

  4. MHD turbulence and distributed chaos

    CERN Document Server

    Bershadskii, A

    2016-01-01

    It is shown, using results of recent direct numerical simulations, that spectral properties of distributed chaos in MHD turbulence with zero mean magnetic field are similar to those of hydrodynamic turbulence. An exception is MHD spontaneous breaking of space translational symmetry, when the stretched exponential spectrum $\\exp(-k/k_{\\beta})^{\\beta}$ has $\\beta=4/7$.

  5. Koedam {beta} factors revisited

    Energy Technology Data Exchange (ETDEWEB)

    Lawler, J.E. [Physics Department, University of Wisconsin, Madison, WI (United States); Doughty, D.A. [Perkin-Elmer Optoelectronics, Santa Clara, CA (United States); Lister, G.G. [OSRAM SYLVANIA Inc., Beverly, MA (United States)

    2002-07-21

    A Koedam {beta} factor makes it possible to compute the total output power in line radiation from a positive column discharge using a single radiance measurement normal to an aperture in the wall. The results of analytic derivations of {beta} factors are presented for columns with uniform ({beta}=1.0) and parabolic ({beta}=0.75) excitation rates per unit volume and with negligible opacity. A Monte Carlo code for simulating radiation trapping with a spatially uniform density of absorbing atoms is then used to determine {beta} factors as a function of opacity. The code includes partial frequency redistribution and a Voigt line shape with radiative broadening, resonance collisional broadening, and Doppler broadening. The resulting {beta} factors are found to be nearly independent of opacity over a wide range of column radii for spectral line shapes dominated by Doppler broadening or by resonance collisional broadening. Additional Monte Carlo simulations are used to study {beta} factors as a function of a non-uniform density of absorbing atoms from radial cataphoresis with line shapes dominated by Doppler broadening, foreign gas broadening, and resonance collisional broadening. Radial cataphoresis is found to increase {beta} factors in all cases. Geometrical effects, refraction, and imperfect transmission at the glass wall are studied and found to decrease {beta} factors. (author)

  6. Beta-energy averaging and beta spectra

    International Nuclear Information System (INIS)

    A simple yet highly accurate method for approximately calculating spectrum-averaged beta energies and beta spectra for radioactive nuclei is presented. This method should prove useful for users who wish to obtain accurate answers without complicated calculations of Fermi functions, complex gamma functions, and time-consuming numerical integrations as required by the more exact theoretical expressions. Therefore, this method should be a good time-saving alternative for investigators who need to make calculations involving large numbers of nuclei (e.g., fission products) as well as for occasional users interested in restricted number of nuclides. The average beta-energy values calculated by this method differ from those calculated by ''exact'' methods by no more than 1 percent for nuclides with atomic numbers in the 20 to 100 range and which emit betas of energies up to approximately 8 MeV. These include all fission products and the actinides. The beta-energy spectra calculated by the present method are also of the same quality

  7. Experimental Study on the Milling of a Ti Beta 21S

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Ti Beta 21S (Ti-15Mo-2.7Nb-3Al-0.2Si) was devel op ed by TIMET in 1989. It is a metastable beta titanium alloy that offers subs tantial weight reductions over other engineering materials. Compared with common beta Ti alloys, it offers the high specific strength, good cold formability, im proved oxidation resistance, elevated temperature strength, creep resistance, an d thermal stability. Besides the common characters of titanium alloy, such as po or heat diffusivity, low elastic modulus, Ti Beta 21S has ...

  8. MECHANICAL STRENGTH OF HIGHLY POROUS CERAMICS

    NARCIS (Netherlands)

    VANDENBORN, IC; SANTEN, A; HOEKSTRA, HD; DEHOSSON, JTM; Born, I.C. van den

    1991-01-01

    This paper reports on the mechanical strength of highly porous ceramics in terms of the Weibull and Duxbury-Leath distributions. More than 1000 side-crushing strength tests on silica-catalyst carriers of various particle sizes have been performed in series. Within a series, preparation conditions we

  9. Measurement of the beta asymmetry in neutron beta decay

    International Nuclear Information System (INIS)

    Neutron beta decay is the simplest semi-leptonic weak decay and described accurately by the standard model using the first CKM-matrix element and the ratio of vector and axial vector couplings, λ. With more than a dozen observables it is a sensitive probe for investigating the nature of weak interaction and to search for physics beyond the standard model. In the past, measuring the beta asymmetry A in polarized neutron decay has been the most precise way of determining λ and nowadays it allows - together with other observables - to derive limits on non-standard model interactions, such as scalar and tensor couplings. The neutron decay spectrometer Perkeo III was installed at the PF1B cold neutron beam site at the Institut Laue-Langevin to measure the beta asymmetry. By using a pulsed beam combined with an improved detector design a significant reduction of several systematic uncertainties has been achieved compared to the predecessor, Perkeo II. In this talk recent results of the measurements with Perkeo III will be presented. In particular, we show the energy distribution of the electrons together with the calibration tools for the detectors.

  10. Double beta decay experiments

    OpenAIRE

    Barabash, A. S.

    2011-01-01

    The present status of double beta decay experiments is reviewed. The results of the most sensitive experiments are discussed. Proposals for future double beta decay experiments with a sensitivity to the $$ at the level of (0.01--0.1) eV are considered.

  11. Negative Beta Encoder

    CERN Document Server

    Kohda, Tohru; Aihara, Kazuyuki

    2008-01-01

    A new class of analog-digital (A/D), digital-analog (D/A) converters as an alternative to conventional ones, called $\\beta$-encoder, has been shown to have exponential accuracy in the bit rates while possessing self-correction property for fluctuations of amplifier factor $\\beta$ and quantizer threshold $\

  12. Betting against Beta

    DEFF Research Database (Denmark)

    Frazzini, Andrea; Heje Pedersen, Lasse

    2014-01-01

    We present a model with leverage and margin constraints that vary across investors and time. We find evidence consistent with each of the model's five central predictions: (1) Because constrained investors bid up high-beta assets, high beta is associated with low alpha, as we find empirically for...

  13. International society of sports nutrition position stand: Beta-Alanine.

    Science.gov (United States)

    Trexler, Eric T; Smith-Ryan, Abbie E; Stout, Jeffrey R; Hoffman, Jay R; Wilborn, Colin D; Sale, Craig; Kreider, Richard B; Jäger, Ralf; Earnest, Conrad P; Bannock, Laurent; Campbell, Bill; Kalman, Douglas; Ziegenfuss, Tim N; Antonio, Jose

    2015-01-01

    The International Society of Sports Nutrition (ISSN) provides an objective and critical review of the mechanisms and use of beta-alanine supplementation. Based on the current available literature, the conclusions of the ISSN are as follows: 1) Four weeks of beta-alanine supplementation (4-6 g daily) significantly augments muscle carnosine concentrations, thereby acting as an intracellular pH buffer; 2) Beta-alanine supplementation currently appears to be safe in healthy populations at recommended doses; 3) The only reported side effect is paraesthesia (tingling), but studies indicate this can be attenuated by using divided lower doses (1.6 g) or using a sustained-release formula; 4) Daily supplementation with 4 to 6 g of beta-alanine for at least 2 to 4 weeks has been shown to improve exercise performance, with more pronounced effects in open end-point tasks/time trials lasting 1 to 4 min in duration; 5) Beta-alanine attenuates neuromuscular fatigue, particularly in older subjects, and preliminary evidence indicates that beta-alanine may improve tactical performance; 6) Combining beta-alanine with other single or multi-ingredient supplements may be advantageous when supplementation of beta-alanine is high enough (4-6 g daily) and long enough (minimum 4 weeks); 7) More research is needed to determine the effects of beta-alanine on strength, endurance performance beyond 25 min in duration, and other health-related benefits associated with carnosine. PMID:26175657

  14. Statistical Analysis of Data for Timber Strengths

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Hoffmeyer, P.

    Statistical analyses are performed for material strength parameters from approximately 6700 specimens of structural timber. Non-parametric statistical analyses and fits to the following distributions types have been investigated: Normal, Lognormal, 2 parameter Weibull and 3-parameter Weibull. The...

  15. Rapid synthesis of beta zeolites

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Wei; Chang, Chun -Chih; Dornath, Paul; Wang, Zhuopeng

    2015-08-18

    The invention provides methods for rapidly synthesizing heteroatom containing zeolites including Sn-Beta, Si-Beta, Ti-Beta, Zr-Beta and Fe-Beta. The methods for synthesizing heteroatom zeolites include using well-crystalline zeolite crystals as seeds and using a fluoride-free, caustic medium in a seeded dry-gel conversion method. The Beta zeolite catalysts made by the methods of the invention catalyze both isomerization and dehydration reactions.

  16. Beta decay of {sup 97}Ag: evidence for the Gamow-Teller resonance near {sup 100}Sn

    Energy Technology Data Exchange (ETDEWEB)

    Hu Zhiqiang

    1999-03-01

    In two complementary measurements, a cube like array of 6 Euroball-Cluster germanium detectors and a total-absorption {gamma}-spectrometer were used to investigate the {beta} decay of {sup 97}Ag, a three proton-hole nucleus with respect to the {sup 100}Sn core. The half-life and Q{sub EC} value of the decay of the 9/2{sup +} ground-state of {sup 97}Ag were determined to be 25.9(4) s and 6.98(11) MeV respectively. A total of 603 {gamma} rays (578 new) was observed, and 151 levels (132 new) in {sup 97}Pd have been identified. An interesting {beta}-delayed {gamma} cascade was observed, which comprises 6 {gamma}-transitions with a de-excitation pattern involving an initial increase of the level spin. The Gamow-Teller (GT) {beta}-decay strength distributions from the two measurements reveal a large GT resonance around 4 MeV with a width of about 1.8 MeV. The hindrance factor for the total GT strength summed from the ground-state up to 6 MeV excitation energy in {sup 97}Pd, amounts to 4.3(6) with reference to a shell-model prediction. This factor is discussed in comparison with a core-polarization and a Monte-Carlo shell-model calculation. (orig.)

  17. Association behavior of native beta-lactoglobulin

    DEFF Research Database (Denmark)

    Verheul, M.; Pedersen, J.S.; Roefs, S.P.F.M.;

    1999-01-01

    The association behavior of beta-lactoglobulin has been studied by small-angle neutron scattering as a function of protein concentration, temperature, pH, and NaCl concentration of the solution. By indirect Fourier transformation of the spectra, pair-distance distribution functions for the various...

  18. Strength analysis of laser welded lap joint for ultra high strength steel

    Science.gov (United States)

    Jeong, Young Cheol; Kim, Cheol Hee; Cho, Young Tae; Jung, Yoon Gyo

    2013-12-01

    Several industries including the automotive industry have recently applied the process of welding high strength steel. High strength steel is steel that is harder than normal high strength steel, making it much stronger and stiffer. HSS can be formed in pieces that can be up to 10 to 15 percent thinner than normal steel without sacrificing strength, which enables weight reduction and improved fuel economy. Furthermore, HSS can be formed into complex shapes that can be welded into structural areas. This study is based on previous experiments and is aimed at establishing the stress distribution for laser welded high strength steel. Research on the stress distribution for laser welded high strength steel is conducted by using Solid Works, a program that analyzes the stress of a virtual model. In conclusion, we found that the stress distribution is changed depending on the shape of welded lap joint. In addition, the Influence of the stress distribution on welded high strength steel can be used to standard for high energy welding of high strength steel, and we can also predict the region in welded high strength steel that may cracked.

  19. Imperfect World of beta beta-decay Nuclear Data Sets

    Energy Technology Data Exchange (ETDEWEB)

    Pritychenko, B. [Brookhaven National Lab. (BNL), Upton, NY (United States). NNDC

    2015-01-03

    The precision of double-beta ββ-decay experimental half lives and their uncertainties is reanalyzed. The method of Benford's distributions has been applied to nuclear reaction, structure and decay data sets. First-digit distribution trend for ββ-decay T2v1/2 is consistent with large nuclear reaction and structure data sets and provides validation of experimental half-lives. A complementary analysis of the decay uncertainties indicates deficiencies due to small size of statistical samples, and incomplete collection of experimental information. Further experimental and theoretical efforts would lead toward more precise values of-decay half-lives and nuclear matrix elements.

  20. Beta-decay rate and beta-delayed neutron emission probability of improved gross theory

    Science.gov (United States)

    Koura, Hiroyuki

    2014-09-01

    A theoretical study has been carried out on beta-decay rate and beta-delayed neutron emission probability. The gross theory of the beta decay is based on an idea of the sum rule of the beta-decay strength function, and has succeeded in describing beta-decay half-lives of nuclei overall nuclear mass region. The gross theory includes not only the allowed transition as the Fermi and the Gamow-Teller, but also the first-forbidden transition. In this work, some improvements are introduced as the nuclear shell correction on nuclear level densities and the nuclear deformation for nuclear strength functions, those effects were not included in the original gross theory. The shell energy and the nuclear deformation for unmeasured nuclei are adopted from the KTUY nuclear mass formula, which is based on the spherical-basis method. Considering the properties of the integrated Fermi function, we can roughly categorized energy region of excited-state of a daughter nucleus into three regions: a highly-excited energy region, which fully affect a delayed neutron probability, a middle energy region, which is estimated to contribute the decay heat, and a region neighboring the ground-state, which determines the beta-decay rate. Some results will be given in the presentation. A theoretical study has been carried out on beta-decay rate and beta-delayed neutron emission probability. The gross theory of the beta decay is based on an idea of the sum rule of the beta-decay strength function, and has succeeded in describing beta-decay half-lives of nuclei overall nuclear mass region. The gross theory includes not only the allowed transition as the Fermi and the Gamow-Teller, but also the first-forbidden transition. In this work, some improvements are introduced as the nuclear shell correction on nuclear level densities and the nuclear deformation for nuclear strength functions, those effects were not included in the original gross theory. The shell energy and the nuclear deformation for

  1. $\\beta$-delayed neutrons from oriented $^{137,139}$I and $^{87,89}$Br nuclei

    CERN Document Server

    Grzywacz, Robert; Stone, Nicholas; Köster, Ulli; Singh, Barlaj; Bingham, Carrol; Gaulard, S; Kolos, Karolina; Madurga, Miguel; Nikolov, J; Otsubo, T; Roccia, S; Veskovic, Miroslav; Walker, Phil; Walters, William

    2013-01-01

    We propose a world-­‐first measurement of the angular distribution of $\\beta$-­‐delayed n and $\\gamma$- radiation from oriented $^{137, 139}$I and $^{87,89}$Br nuclei, polarised at low temperature at the NICOLE facility. $\\beta$-­‐delayed neutron emission is an increasingly important decay mechanism as the drip line is approached and its detailed understanding is essential to phenomena as fundamental as the r‐process and practical as the safe operation of nuclear power reactors. The experiments offer sensitive tests of theoretical input concerning the allowed and first-­‐forbidden $\\beta$‐decay strength, the spin-­‐density of neutron emitting states and the partial wave barrier penetration as a function of nuclear deformation. In $^{137}$I and $^{87}$Br the decay feeds predominantly the ground state of the daughters $^{136}$Xe and $^{86}$Kr whereas in $^{139}$I and $^{89}$Br we will explore the use of n-$\\gamma$- coincidence to study neutron transitions to the first and second excited state...

  2. $\\beta$-delayed neutrons from oriented $^{137,139}$I and $^{87,89}$Br nuclei

    CERN Multimedia

    We propose a world-first measurement of the angular distribution of $\\beta$‐delayed n and $\\gamma$-radiation from oriented $^{137, 139}$I and $^{87,89}$Br nuclei, polarised at low temperature at the NICOLE facility. $\\beta$­-delayed neutron emission is an increasingly important decay mechanism as the drip line is approached and its detailed understanding is essential to phenomena as fundamental as the r‐process and practical as the safe operation of nuclear power reactors. The experiments offer sensitive tests of theoretical input concerning the allowed and first­‐forbidden $\\beta$‐decay strength, the spin-density of neutron emitting states and the partial wave barrier penetration as a function of nuclear deformation. In $^{137}$I and $^{87}$Br the decay feeds predominantly the ground state of the daughters $^{136}$Xe and $^{86}$Kr whereas in $^{139}$I and $^{89}$Br we will explore the use of n-$\\gamma$- coincidence to study neutron transitions to the first and second excited states in the daughters...

  3. Beta-carotene

    Science.gov (United States)

    ... and deterioration of the lining of the mouth (oral mucositis). Taking beta-carotene by mouth doesn’t appear to prevent the development of oral mucositis during radiation therapy or chemotherapy. Pancreatic cancer. Taking ...

  4. Neutrinoless double beta decay

    International Nuclear Information System (INIS)

    The physics potential of neutrinoless double beta decay is discussed. Furthermore, experimental considerations as well as the current status of experiments are presented. Finally, an outlook towards the future, work on nuclear matrix elements and alternative processes is given. (author)

  5. Neutrinoless double beta decay

    Indian Academy of Sciences (India)

    Kai Zuber

    2012-10-01

    The physics potential of neutrinoless double beta decay is discussed. Furthermore, experimental considerations as well as the current status of experiments are presented. Finally, an outlook towards the future, work on nuclear matrix elements and alternative processes is given.

  6. Charge exchange nuclear excitations and beta decay within the self consistent deformed QRPA

    International Nuclear Information System (INIS)

    Spin-isospin nuclear excitations play a crucial role in astrophysics where they govern beta-decay, electron and neutrino capture processes, hence stellar evolution and nucleosynthesis. These excitations are studied here within the fully self-consistent proton-neutron quasiparticle random-phase approximation using the finite-range Gogny interaction. Axially symmetric deformations are consistently taken into account, both in the description of the ground states and spin-isospin excitations. We focus in particular on the Gamow-Teller excitations. A comparison of the predicted strength distributions to the existing experimental data is presented and the role of nuclear deformation analyzed. The Gamow-Teller strength is used to estimate the beta-decay half-life of nuclei for which experimental data exist. A satisfactory agreement with experimental half-lives is found and justifies the additional study of the exotic neutron-rich N=82, 126 and 184 isotonic chains of relevance for the r-process nucleosynthesis. We also show the comparison between our theoretical predictions and the experimental half-lives for the much studied isotopic chains of Kr, Sr, Zr and Mo which are strongly deformed. (author)

  7. [High beta tokamak research

    International Nuclear Information System (INIS)

    Our activities on High Beta Tokamak Research during the past 20 months of the present grant period can be divided into six areas: reconstruction and modeling of high beta equilibria in HBT; measurement and analysis of MHD instabilities observed in HBT; measurements of impurity transport; diagnostic development on HBT; numerical parameterization of the second stability regime; and conceptual design and assembly of HBT-EP. Each of these is described in some detail in the sections of this progress report

  8. High beta multipoles

    International Nuclear Information System (INIS)

    Multipoles are being employed as devices to study fusion issues and plasma phenomena at high values of beta (plasma pressure/magnetic pressure) in a controlled manner. Due to their large volume, low magnetic field (low synchrotron radiation) region, they are also under consideration as potential steady state advanced fuel (low neutron yield) reactors. Present experiments are investigating neoclassical (bootstrap and Pfirsch-Schlueter) currents and plasma stability at extremely high beta

  9. Autoregressive conditional beta

    OpenAIRE

    Yunmi Kim

    2012-01-01

    The capital asset pricing model provides various predictions about equilibrium expected returns on risky assets. One key prediction is that the risk premium on a risky asset is proportional to the nondiversifiable market risk measured by the asset's beta coefficient. This paper proposes a new method for estimating and drawing inferences from a time-varying capital asset pricing model. The proposed method, which can be considered a vector autoregressive model for multiple beta coefficients, is...

  10. Beta decay properties from a statistical model

    International Nuclear Information System (INIS)

    The present work assumes that any intrinsic structure in the nuclei involved is not important. Only spin, parity, and energy are considered. Quantities such as half-life, average beta energy, or average gamma energy can be obtained by integrals over the beta strength function weighted by kinematic and other factors. The beta strength function is proportional to the level density multiplied by a reduced transition probability. Delayed neutron emission is calculated by assuming that the daughter is a compound nucleus which then statistically decays as in the Hauser-Feshbach approach. Using the ENDF/B-V fission product file which contains 877 nuclei, energy-dependent reduced transition probabilities were found for allowed 0+ → 1+ transitions (50 cases) and for other allowed transitions (over 600 cases), corresponding to log ft values of 4.3 and 5.6 respectively. No dependence on either transition energy or on mass was found. A reduced transition probability corresponding to log ft of 7.1 was used for first forbidden transitions. Some results are presented and discussed

  11. Large-scale calculations of the beta-decay rates and r-process nucleosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Borzov, I.N.; Goriely, S. [Inst. d`Astronomie et d`Astrophysique, Univ. Libre de Bruxelles, Campus Plaine, Bruxelles (Belgium); Pearson, J.M. [Inst. d`Astronomie et d`Astrophysique, Univ. Libre de Bruxelles, Campus Plaine, Bruxelles (Belgium)]|[Lab. de Physique Nucleaire, Univ. de Montreal, Montreal (Canada)

    1998-06-01

    An approximation to a self-consistent model of the ground state and {beta}-decay properties of neutron-rich nuclei is outlined. The structure of the {beta}-strength functions in stable and short-lived nuclei is discussed. The results of large-scale calculations of the {beta}-decay rates for spherical and slightly deformed nuclides of relevance to the r-process are analysed and compared with the results of existing global calculations and recent experimental data. (orig.)

  12. Applications of TAGS data in beta decay energies and decay heat calculations

    OpenAIRE

    Pham, N. S.; 片倉 純一

    2007-01-01

    The recent data of beta-decay intensity measured by using the total absorption gamma-ray spectrometer (TAGS), for several fission products (FP), has been applied for calculations of the average energies and spectra, and decay heat summations. The calculations were performed based on the Gross theory of beta decay, in which the beta strength functions were experimentally derived from TAGS data. The deviations of decay heat power predictions from the original decay data of JENDL Decay Data File...

  13. High-resolution studies of beta-delayed proton emitters at IGISOL facility

    NARCIS (Netherlands)

    Jokinen, A; Aysto, J; Dendooven, P; Hankonen, S; Honkanen, A; Huikari, J; Lhersonneau, G; Lipas, PO; Penttila, H; Perajarvi, K; Oinonen, M; Nieminen, A; Siiskonen, T; Wang, JC

    1998-01-01

    Beta-decays of Al-23 and Ti-41 have been studied by applying ion guide techniques, gamma detection and a gas-Si telescope for charged-particle detection. The experimental beta-decay strength of Ti-41 was found to be quenched by a factor of q(2) = 0.64 compared to our shell model calculations below 8

  14. Beta-secretase-cleaved amyloid precursor protein in Alzheimer brain: a morphologic study

    DEFF Research Database (Denmark)

    Sennvik, Kristina; Bogdanovic, N; Volkmann, Inga; Fastbom, J; Benedikz, Eirikur

    2004-01-01

    (beta-sAPP) in brain tissue sections from the frontal, temporal and occipital lobe. Strong granular beta-sAPP staining was found throughout the gray matter of all three areas, while white matter staining was considerably weaker. beta-sAPP was found to be localized in astrocytes and in axons. We found...... the beta-sAPP immunostaining to be stronger and more extensive in gray matter in Alzheimer disease (AD) cases than controls. The axonal beta-sAPP staining was patchy and unevenly distributed for the AD cases, indicating impaired axonal transport. beta-sAPP was also found surrounding senile plaques and......beta-amyloid (Abeta) is the main constituent of senile plaques seen in Alzheimer's disease. Abeta is derived from the amyloid precursor protein (APP) via proteolytic cleavage by proteases beta- and gamma-secretase. In this study, we examined content and localization of beta-secretase-cleaved APP...

  15. Shell model description of Gamow-Teller strengths for $^{42}$Ti, $^{46}$Cr, $^{50}$Fe and $^{54}$Ni

    CERN Document Server

    Kumar, Vikas; Hirsch, Jorge G

    2015-01-01

    A systematic shell model description of the experimental Gamow-Teller transition strength distributions in $^{42}$Ti, $^{46}$Cr, $^{50}$Fe and $^{54}$Ni is presented. These transitions have been recently measured via $\\beta$ decay of these $T_z$=-1 nuclei, produced in fragmentation reactions at GSI and also with ($^3${He},$t$) charge-exchange (CE) reactions corresponding to $T_z = + 1$ to $T_z = 0$ carried out at RCNP-Osaka. The calculations are performed in the $pf$ model space, using the GXPF1a and KB3G effective interactions. Qualitative agreement is obtained for the individual transitions, while the calculated summed transition strengths closely reproduce the observed ones.

  16. ON STRAIN RATE SENSITIVITY OF BETA-TITANIUM ALLOYS

    OpenAIRE

    Kobayashi, A.; Takeda, N.; Ogihara, S.; Li, Y.

    1991-01-01

    Ti-15V-3Cr-3A1-3Sn beta-titanium alloys are subjected to 103/s tensile strain rate by the one bar method to investigate strain rate sensitivity. It is found that the ultimate strength, the total elongation and the absorbed energy, all increase with the increase in strain rate. Dynamical stress-strain curves are also obtained.

  17. Extrasynaptic location of laminin beta 2 chain in developing and adult human skeletal muscle.

    OpenAIRE

    Wewer, U M; Thornell, L. E.; Loechel, F; Zhang, X.; Durkin, M. E.; Amano, S; Burgeson, R. E.; Engvall, E; Albrechtsen, R.; Virtanen, I.

    1997-01-01

    We have investigated the distribution of the laminin beta 2 chain (previously s-laminin) in human fetal and adult skeletal muscle and compared it to the distribution of laminin beta 1. Immunoblotting and transfection assays were used to characterize a panel of monoclonal and polyclonal antibodies to the laminin beta 2 chain. We found that laminin beta 1 chain was detected at all times during development from 10 weeks of gestation. Laminin beta 2 chain was first detected in 15 to 22-week-old f...

  18. High strength ferritic alloy

    International Nuclear Information System (INIS)

    A high strength ferritic steel is specified in which the major alloying elements are chromium and molybdenum, with smaller quantities of niobium, vanadium, silicon, manganese and carbon. The maximum swelling is specified for various irradiation conditions. Rupture strength is also specified. (U.K.)

  19. Improvement of Cement Strength by Induction Method

    Institute of Scientific and Technical Information of China (English)

    YANG Li-yuan; LIN Zong-shou

    2004-01-01

    The induction method of improving the strength of Portland cement by adding fine slag powder,high aluminate component and hydrated paste was investigated through determining the physical properties,hydration heat and pore size distribution,and its mechanism was discussed.The experimental results reveal that a certain content of high aluminate component,fine slag powder and hydrated paste can improve remarkably the strength of Portland cement.

  20. High-beta plasma blobs in the morningside plasma sheet

    Directory of Open Access Journals (Sweden)

    G. Haerendel

    Full Text Available Equator-S frequently encountered, i.e. on 30% of the orbits between 1 March and 17 April 1998, strong variations of the magnetic field strength of typically 5–15-min duration outside about 9RE during the late-night/early-morning hours. Very high-plasma beta values were found, varying between 1 and 10 or more. Close conjunctions between Equator-S and Geotail revealed the spatial structure of these "plasma blobs" and their lifetime. They are typically 5–10° wide in longitude and have an antisymmetric plasma or magnetic pressure distribution with respect to the equator, while being altogether low-latitude phenomena 
    (≤ 15°. They drift slowly sunward, exchange plasma across the equator and have a lifetime of at least 15–30 min. While their spatial structure may be due to some sort of mirror instability, little is known about the origin of the high-beta plasma. It is speculated that the morningside boundary layer somewhat further tailward may be the source of this plasma. This would be consistent with the preference of the plasma blobs to occur during quiet conditions, although they are also found during substorm periods. The relation to auroral phenomena in the morningside oval is uncertain. The energy deposition may be mostly too weak to generate a visible signature. However, patchy aurora remains a candidate for more disturbed periods.

    Key words. Magnetospheric physics (plasma convection; plasma sheet; plasma waves and instabilities

  1. Double beta decay experiments

    International Nuclear Information System (INIS)

    The great sensitivity of double beta decay to neutrino mass and right handed currents has motivated many new and exciting attempts to observe this elusive nuclear phenomenon directly. Experiments in operation and other coming on line in the next one or two years are expected to result in order-of-magnitude improvements in detectable half lives for both the two-neutrino and no-neutrino modes. A brief history of double beta decay experiments is presented together with a discussion of current experimental efforts, including a gas filled time projection chamber being used to study selenium-82. (author)

  2. Plasma beta HCG determination

    International Nuclear Information System (INIS)

    There are three important indications for the early diagnosis of pregnancy through the determination of the beta sub-unit of chorionic gonadotrophin using radioimmunoassay: 1) some patient's or doctor's anxiety to discover the problem; 2) when it will be necessary to employ diagnostic or treatment procedures susceptible to affect the ovum; and 3) in the differential diagnosis of amenorrhoea, uterine hemorrhage and abdominal tumors. Other user's are the diagnosis of missed absortion, and the diagnosis and follow-up of chrorioncarcinoma. The AA. studied 200 determinations of plasma beta-HCG, considering the main difficulties occuring in the clinical use of this relevant laboratory tool in actual Obstetrics. (author)

  3. Beta and Gamma Gradients

    DEFF Research Database (Denmark)

    Løvborg, Leif; Gaffney, C. F.; Clark, P. A.;

    1985-01-01

    Experimental and/or theoretical estimates are presented concerning, (i) attenuation within the sample of beta and gamma radiation from the soil, (ii) the gamma dose within the sample due to its own radioactivity, and (iii) the soil gamma dose in the proximity of boundaries between regions of...... differing radioactivity. It is confirmed that removal of the outer 2 mm of sample is adequate to remove influence from soil beta dose and estimates are made of the error introduced by non-removal. Other evaluations include variation of the soil gamma dose near the ground surface and it appears that the...

  4. Weak interaction studies from nuclear beta decay

    International Nuclear Information System (INIS)

    The studies performed at the theoretical nuclear physics division of the Laboratory of Nuclear Studies, Osaka University, are reported. Electron spin density and internal conversion process, nuclear excitation by electron transition, beta decay, weak charged current, and beta-ray angular distributions in oriented nuclei have been studied. The relative intensity of internal conversion electrons for the case in which the radial wave functions of orbital electrons are different for electron spin up and down was calculated. The calculated value was in good agreement with the experimental one. The nuclear excitation following the transition of orbital electrons was studied. The calculated probability of the nuclear excitation of Os189 was 1.4 x 10-7 in conformity with the experimental value 1.7 x 10-7. The second class current and other problems on beta-decay have been extensively studied, and described elsewhere. Concerning weak charged current, the effects of all induced terms, the time component of main axial vector, all partial waves of leptons, Coulomb correction for the electrons in finite size nuclei, and radiative correction were studied. The beta-ray angular distribution for the 1+ -- 0+ transition in oriented B12 and N12 was investigated. In this connection, investigation on the weak magnetism to include all higher order corrections for the evaluation of the spectral shape factors was performed. Other works carried out by the author and his collaborators are also explained. (Kato, T.)

  5. Strength functions for fragmented doorway states

    International Nuclear Information System (INIS)

    Coupling a strongly excited ''doorway state'' to weak ''hallway states'' distributes its strength into micro-resonances seen in differential cross sections taken with very good energy resolution. The distribution of strength is shown to be revealed by reduced widths of the K-matrix rather than by the imaginary part of poles of the S-matrix. Different strength functions (SF) constructed by averaging the K-matrix widths are then investigated to determine their dependences on energy and on parameters related to averages of microscopic matrix elements. A new sum rule on the integrated strength of these SF is derived and used to show that different averaging procedures actually distribute the strength differently. Finally, it is shown that the discontinuous summed strength defines spreading parameters for the doorway state only in strong coupling, where it approximates the idefinite integral of the continuous SF of MacDonald-Mekjian-Kerman-De Toledo Piza. A new method of ''parametric continuation'' is used to relate a discontinuous sliding box-average, or a finite sum, of discrete terms to a continous function

  6. Beta-decay of the N=Z nucleus 72Kr

    International Nuclear Information System (INIS)

    The beta-decay of the N = Z, even-even nucleus 72Kr has been studied at the ISOLDE PSB facility at CERN. Measurements of βγ and βγγ coincidences have enriched the decay scheme of the daughter nucleus 72Br with 27 new low spin levels. A more precise half-life of T1/2 = 17.1(2) s has been determined. Strong feeding to the 72Br ground state is established yielding an unambiguous Jπ = 1+ assignment for this state. Candidates for the 72Br g.s. wave function are discussed in the framework of a self-consistent deformed mean-field calculation with SG2 Skyrme force and pairing correlations. A search for beta-delayed particle emission was made and an upper limit of 10-6 for this decay branch obtained. The cumulated experimental level density of 1+ states has been fitted with the constant temperature formula. The comparison indicates that most likely all 1+ levels up to 1.2 MeV have been observed in this investigation. The corresponding nearest-neighbour level spacing does not follow a Poisson distribution. The Gamow-Teller strength distribution is compared, in terms of nuclear deformation, with different calculations made in the framework of the quasiparticle random phase approximation. (orig.)

  7. Electromagnetic Transition Strengths in Heavy Nuclei

    CERN Document Server

    Buck, B; Perez, S M

    2012-01-01

    We calculate reduced B(E2) and B(M1) electromagnetic transition strengths within and between K-bands in support of a recently proposed model for the structure of heavy nuclei. Previously, only spectra and a rough indication of the largest B(E2) strengths were reported. The present more detailed calculations should aid the experimental identification of the predicted $0^+$, $1^+$ and $2^+$ bands and, in particular, act to confirm or refute the suggestion that the model $0^+$ and $2^+$ bands correspond to the well known and widespread beta and gamma bands. Furthermore they pinpoint transitions which can indicate the presence of a so far elusive $1^+$ band by feeding relatively strongly into or out of it. Some of these transitions may already have been measured in $^{230}$Th, $^{232}$Th and $^{238}$U.

  8. Evaluation of neutrino masses from $m_{\\beta\\beta}$ values

    CERN Document Server

    Khrushchov, V V

    2008-01-01

    A neutrino mass matrix is considered under conditions of the CP invariance and the negligible reactor mixing $\\theta_{13}$ angle. Absolute mass values for three neutrinos are evaluated in normal and inverted hierarchy spectra on the ground of data for oscillation mixing neutrino parameters and effective neutrino mass entering into a probability of neutrinoless two beta decay $m_{\\beta\\beta}$ values.

  9. Shape effects along the Z=82 line: study of the $\\beta$- decay of $^{188,190,192}$Pb using total absorption spectroscopy

    CERN Multimedia

    Caballero ontanaya, L; Garcia borge, M J; Malbrunot, S

    2002-01-01

    This proposal is aimed at the study of the $\\beta$- decay of the neutron-deficient $^{188,190,192}$Pb nuclei. The main motivation of the proposed experiment is to determine the Gamow-Teller strength distribution in the daughter nuclei using the Total Absorption Spectrometer "Lucrecia". Recent theoretical results show that from this measurement the shapes of the ground states of the decaying Pb nuclei can be inferred. This study offers an independent way to study the phenomenon of shape co-existence in a region of particular interest.

  10. Studies of the $\\beta$-decay of Kr and Sr nuclei on and near the N=Z line with a Total Absorption $\\gamma$-ray Spectrometer

    CERN Multimedia

    2002-01-01

    It is proposed to measure the Gamow-Teller strength distribution in the decays of $^{71-75}$Kr and $^{75,76}$Sr using a Total Absorption Gamma-ray Spectrometer (TAGS) based on a large NaI(TI) detector. The $\\gamma$-rays emitted in these decays will be detected in the TAGS in coincidence with positrons and X-rays from electron capture. Measurements of $\\beta$-delayed particles will also be performed in coincidence with the TAGS. Comparison with theoretical calculations based on the mean field approach, Tamm-Dancoff and QRPA method should allow a determination of the shapes of the ground states of these nuclei.

  11. Off-momentum beta-beat correction in the RHIC proton run

    Energy Technology Data Exchange (ETDEWEB)

    Luo Y.; Bai, M.; Fischer, W.; Marusic, A.; Mernick, K.; White, S.

    2012-05-20

    In this article, we will review the techniques to measure the off-momentum {beta}-beat and the correction algorithms with the chromatic arc sextupoles in RHIC. We will focus on the measurement and correction of the off-momentum {beta}*-beat at the interaction points. The off-momentum {beta}* is measured with the quadrupole strength change and a high resolution phase lock loop tune meter. The results of off-momentum {beta}* correction performed in a dedicated beam experiment in the 2012 RHIC 250 GeV polarized proton run are presented.

  12. Failure of the gross theory of beta decay in neutron deficient nuclei

    International Nuclear Information System (INIS)

    The neutron deficient isotopes 117-121Xe, 117-124Cs, and 122-124Ba were produced by a beam of 28Si from the LBNL SuperHILAC on a target of natMo. The isotopes were mass separated and their beta decay schemes were measured with a Total Absorption Spectrometer (TAS). The beta strengths derived from these data decreased dramatically to levels above ≈1 MeV for the even-even decays; 3–4 MeV for even-Z, odd-N decays; 4–5 MeV for the odd-Z, even-N decays; and 7–8 MeV for the odd-Z, odd-N decays. The decreasing strength to higher excitation energies in the daughters contradicts the predictions of the Gross Theory of Beta Decay. The integrated beta strengths are instead found to be consistent with shell model predictions where the single-particle beta strengths are divided amoung many low-lying levels. The experimental beta strengths determined here have been used calculate the half-lives of 143 neutron deficient nuclei with Z=51–64 to a precision of 20% with respect to the measured values

  13. Low-beta structures

    OpenAIRE

    M. Vretenar(CERN, Geneva, Switzerland)

    2012-01-01

    'Low-beta' radio-frequency accelerating structures are used in the sections of a linear accelerator where the velocity of the particle beam increases with energy. The requirement for space periodicity to match the increasing particle velocity led to the development of a large variety of structures, both normal and superconducting, which are described in this lecture.

  14. Applied Beta Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Rich, B.L.

    1986-01-01

    Measurements of beta and/or nonpenetrating exposure results is complicated and past techniques and capabilities have resulted in significant inaccuracies in recorded results. Current developments have resulted in increased capabilities which make the results more accurate and should result in less total exposure to the work force. Continued development of works in progress should provide equivalent future improvements.

  15. Roughing up Beta

    DEFF Research Database (Denmark)

    Bollerslev, Tim; Li, Sophia Zhengzi; Todorov, Viktor

    Motivated by the implications from a stylized equilibrium pricing framework, we investigate empirically how individual equity prices respond to continuous, or \\smooth," and jumpy, or \\rough," market price moves, and how these different market price risks, or betas, are priced in the cross-section...

  16. Neutrinoless Double Beta Decay

    CERN Document Server

    Päs, Heinrich

    2015-01-01

    We review the potential to probe new physics with neutrinoless double beta decay $(A,Z) \\to (A,Z+2) + 2 e^-$. Both the standard long-range light neutrino mechanism as well as short-range mechanisms mediated by heavy particles are discussed. We also stress aspects of the connection to lepton number violation at colliders and the implications for baryogenesis.

  17. Applied Beta Dosimetry

    International Nuclear Information System (INIS)

    Measurements of beta and/or nonpenetrating exposure results is complicated and past techniques and capabilities have resulted in significant inaccuracies in recorded results. Current developments have resulted in increased capabilities which make the results more accurate and should result in less total exposure to the work force. Continued development of works in progress should provide equivalent future improvements

  18. Gamow-Teller and First-Forbidden Transition Strengths in Astrophysical Processes

    International Nuclear Information System (INIS)

    Gamow-Teller (GT) and first-forbidden (FF) transitions in nuclei and their possible consequences on astrophysical processes in stars are discussed. GT transition strengths in fp-shell nuclei are studied by shell model calculations with the use of new shell model Hamiltonians, GXPF1. Neutrino-nucleus reaction cross sections are re-evaluated and compared with previous investigations. Proton emission cross sections on 56Ni are pointed out to be enhanced and lead to the enhancement of the production yields of 55Mn and 59Co in population III supernovae. Next, electron capture reactions on Ni and Fe isotopes in steller environments are studied. The capture rates depend sensitively on the distributions of the GT strengths. Capture rates on 58Ni and 60Ni obtained by GXPF1 are found to reproduce rather well those obtained from experimental GT strengths. Finally, beta decays of the N = 126 isotones are studied by shell model calculations taking into account both the GT and FF transitions. The FF transitions are found to be important to reduce the half-lives by twice to several times of those by the GT contributions only. Possible implications on the short half-lives of the waiting point nuclei on the r-process nucleosynthesis are discussed for certain astrophysical conditions.

  19. Interferon Beta-1b Injection

    Science.gov (United States)

    Interferon beta-1b injection is used to reduce episodes of symptoms in patients with relapsing-remitting (course ... and problems with vision, speech, and bladder control). Interferon beta-1b is in a class of medications ...

  20. Genetics Home Reference: beta thalassemia

    Science.gov (United States)

    ... for Disease Control and Prevention Centre for Genetics Education (Australia) Cold Spring Harbor Laboratory: Your Genes Your Health Disease InfoSearch: Beta Thalassemia Genomics Education Programme (UK) MalaCards: dominant beta-thalassemia Merck Manual ...

  1. Source preparations for alpha and beta measurements

    Energy Technology Data Exchange (ETDEWEB)

    Holm, E. [Risoe National Lab., Roskilde (Denmark)

    2001-01-01

    Regarding alpha particle emitters subject for environmental studies, electrodeposition or co-precipitation as fluorides are the most common methods. For electro deposition stainless steel is generally used as cathode material but also other metals such as Ni, Ag, and Cu showed promising results. The use of other anode material than platinum, such as graphite should be investigated. For other purposes such as optimal resolution other more sophisticated methods are used but often resulting in poorer recovery. For beta particle emitters the type of detection system will decide the source preparation. Similar methods as for alpha particle emitters, electrodeposition or precipitation techniques can be used. Due to the continuous energy distribution of the beta pulse height distribution a high resolution is not required. Thicker sources from the precipitates or a stable isotopic carrier can be accepted but correction for absorption in the source must be done. (au)

  2. Source preparations for alpha and beta measurements

    International Nuclear Information System (INIS)

    Regarding alpha particle emitters subject for environmental studies, electrodeposition or co-precipitation as fluorides are the most common methods. For electro deposition stainless steel is generally used as cathode material but also other metals such as Ni, Ag, and Cu showed promising results. The use of other anode material than platinum, such as graphite should be investigated. For other purposes such as optimal resolution other more sophisticated methods are used but often resulting in poorer recovery. For beta particle emitters the type of detection system will decide the source preparation. Similar methods as for alpha particle emitters, electrodeposition or precipitation techniques can be used. Due to the continuous energy distribution of the beta pulse height distribution a high resolution is not required. Thicker sources from the precipitates or a stable isotopic carrier can be accepted but correction for absorption in the source must be done. (au)

  3. Beta gets better with age

    OpenAIRE

    Tomunen, Tuomas

    2015-01-01

    The objective of my thesis is to study the cause for the low beta anomaly, which is an observation that the high beta stocks perform poorly relative to the low beta stocks. Based on earlier findings, I hypothesize that if a stock has high investor attention, its price overreacts to market-wide shocks, which results in a positive measurement error in its beta. Simultaneously, high attention causes overpricing, because the stock overreacts more often to positive shocks than to negat...

  4. Evidence for the presence of beta 3-adrenergic receptor mRNA in the human brain.

    Science.gov (United States)

    Rodriguez, M; Carillon, C; Coquerel, A; Le Fur, G; Ferrara, P; Caput, D; Shire, D

    1995-04-01

    The beta 3-adrenergic receptor (AR) is widely distributed in peripheral tissues, but up to now it has not been detected in the central nervous system. By using the polymerase chain reaction (PCR) technique, we found the beta 3-AR mRNA to be present in all the regions of the human brain we investigated. The quantities found were very low compared to those of the beta 1-AR and beta 2-AR mRNAs, being hardly detectable in adult brain. In contrast, the brain of very young infants contained about 100 times more beta 3-AR mRNA than the adult brain, whereas the amounts of beta 1-AR and beta 2-AR transcripts were essentially the same. In addition, using PCR we have cloned a central beta 3-AR coding region from a human frontal cortex cDNA library and have found it to be identical to the corresponding peripheral sequence. PMID:7609625

  5. Extrasynaptic location of laminin beta 2 chain in developing and adult human skeletal muscle

    DEFF Research Database (Denmark)

    Wewer, U M; Thornell, L E; Loechel, F; Zhang, X; Durkin, M E; Amano, S; Burgeson, R E; Engvall, E; Albrechtsen, R; Virtanen, I

    1997-01-01

    to the laminin beta 2 chain. We found that laminin beta 1 chain was detected at all times during development from 10 weeks of gestation. Laminin beta 2 chain was first detected in 15 to 22-week-old fetal skeletal muscle as distinct focal immunoreactivity in the sarcolemmal basement membrane area of...... some myofibers. In the adult skeletal muscle, laminin beta 2 chain immunoreactivity was found along the entire perimeter of each of the individual myofibers in a large series of different muscles studied. Laminin beta 2 chain was similarly found in the skeletal muscle basement membranes in patients......We have investigated the distribution of the laminin beta 2 chain (previously s-laminin) in human fetal and adult skeletal muscle and compared it to the distribution of laminin beta 1. Immunoblotting and transfection assays were used to characterize a panel of monoclonal and polyclonal antibodies...

  6. Misleading Betas: An Educational Example

    Science.gov (United States)

    Chong, James; Halcoussis, Dennis; Phillips, G. Michael

    2012-01-01

    The dual-beta model is a generalization of the CAPM model. In the dual-beta model, separate beta estimates are provided for up-market and down-market days. This paper uses the historical "Anscombe quartet" results which illustrated how very different datasets can produce the same regression coefficients to motivate a discussion of the…

  7. Effect of bootstrap current on MHD equilibrium beta limit in heliotron plasmas

    International Nuclear Information System (INIS)

    The effect of bootstrap current on the beta limit of MHD equilibria is studied systematically by an iterative calculation of MHD equilibrium and the consistent bootstrap current in high beta heliotron plasmas. The LHD machine is treated as a standard configuration heliotron with an L=2 planar axis. The effects of vacuum magnetic configurations, pressure profiles and the vertical field control method are studied. The equilibrium beta limit with consistent bootstrap current is quite sensitive to the magnetic axis location for finite beta, compared with the currentless cases. For a vacuum configuration with the magnetic axis shifted inwards in the torus, even in the high beta regimes, the bootstrap current flows to increase the rotational transform, leading to an increase in the equilibrium beta limit. On the contrary, for a vacuum configuration with the magnetic axis shifted outwards in the torus, even in the low beta regimes, the bootstrap current flows so as to reduce the rotational transform; therefore, there is an acceleration of the Shafranov shift increase as beta increases, leading to a decrease in the equilibrium beta limit. The pressure profiles and vertical field control methods influence the equilibrium beta limit through the location of the magnetic axis for finite beta. These characteristics are independent of both device parameters, such as magnetic field strength, and device size in the low collisional regime. (author)

  8. First observation of $\\beta$-delayed $\\gamma$-proton decay in the $T_z$ = -2, $^{56}$Zn nucleus

    CERN Document Server

    Orrigo, S E A; Fujita, Y; Blank, B; Gelletly, W; Agramunt, J; Algora, A; Ascher, P; Bilgier, B; Cáceres, L; Cakirli, R B; Fujita, H; Ganioğlu, E; Gerbaux, M; Giovinazzo, J; Grévy, S; Kamalou, O; Kozer, H C; Kucuk, L; Kurtukian-Nieto, T; Molina, F; Popescu, L; Rogers, A M; Susoy, G; Stodel, C; Suzuki, T; Tamii, A; Thomas, J C

    2014-01-01

    We report on the first experimental observation of a very exotic decay mode at the proton drip-line, the $\\beta$-delayed $\\gamma$-proton decay, clearly seen in the $\\beta$ decay of the $T_z$ = -2, $^{56}$Zn nucleus. The $^{56}$Zn half-life and decay scheme have been determined. The decay proceeds by $\\beta$-delayed proton emission and $\\beta$-delayed $\\gamma$ de-excitation. The exotic $\\beta$-delayed $\\gamma$-proton emission was also detected in three cases. It affects the usual determination of the Gamow-Teller (GT) strength. Absolute Fermi and GT strengths have been deduced. Evidence for fragmentation of the Fermi strength due to isospin mixing is found.

  9. Beta-thalassemia

    Directory of Open Access Journals (Sweden)

    Origa Raffaella

    2010-05-01

    Full Text Available Abstract Beta-thalassemias are a group of hereditary blood disorders characterized by anomalies in the synthesis of the beta chains of hemoglobin resulting in variable phenotypes ranging from severe anemia to clinically asymptomatic individuals. The total annual incidence of symptomatic individuals is estimated at 1 in 100,000 throughout the world and 1 in 10,000 people in the European Union. Three main forms have been described: thalassemia major, thalassemia intermedia and thalassemia minor. Individuals with thalassemia major usually present within the first two years of life with severe anemia, requiring regular red blood cell (RBC transfusions. Findings in untreated or poorly transfused individuals with thalassemia major, as seen in some developing countries, are growth retardation, pallor, jaundice, poor musculature, hepatosplenomegaly, leg ulcers, development of masses from extramedullary hematopoiesis, and skeletal changes that result from expansion of the bone marrow. Regular transfusion therapy leads to iron overload-related complications including endocrine complication (growth retardation, failure of sexual maturation, diabetes mellitus, and insufficiency of the parathyroid, thyroid, pituitary, and less commonly, adrenal glands, dilated myocardiopathy, liver fibrosis and cirrhosis. Patients with thalassemia intermedia present later in life with moderate anemia and do not require regular transfusions. Main clinical features in these patients are hypertrophy of erythroid marrow with medullary and extramedullary hematopoiesis and its complications (osteoporosis, masses of erythropoietic tissue that primarily affect the spleen, liver, lymph nodes, chest and spine, and bone deformities and typical facial changes, gallstones, painful leg ulcers and increased predisposition to thrombosis. Thalassemia minor is clinically asymptomatic but some subjects may have moderate anemia. Beta-thalassemias are caused by point mutations or, more rarely

  10. Beta and muon decays

    International Nuclear Information System (INIS)

    These notes represent a series of lectures delivered by the authors in the Junta de Energia Nuclear, during the Spring term of 1965. They were devoted to graduate students interested in the Theory of Elementary Particles. Special emphasis was focussed into the computational problems. Chapter I is a review of basic principles (Dirac equation, transition probabilities, final state interactions.) which will be needed later. In Chapter II the four-fermion punctual Interaction is discussed, Chapter III is devoted to the study of beta-decay; the main emphasis is given to the deduction of the formulae corresponding to electron-antineutrino correlation, electron energy spectrum, lifetimes, asymmetry of electrons emitted from polarized nuclei, electron and neutrino polarization and time reversal invariance in beta decay. In Chapter IV we deal with the decay of polarized muons with radiative corrections. Chapter V is devoted to an introduction to C.V.C. theory. (Author)

  11. Integration of BETA with Eclipse

    DEFF Research Database (Denmark)

    Andersen, Peter; Madsen, Ole Lehrmann; Enevoldsen, Mads Brøgger

    2004-01-01

    This paper presents language interoperability issues appearing in order to implement support for the BETA language in the Java-based Eclipse integrated development environment. One of the challenges is to implement plug-ins in BETA and be able to load them in Eclipse. In order to do this, some form...... of language interoperability between Java and BETA is required. The first approach is to use the Java Native Interface and use C to bridge between Java and BETA. This results in a workable, but complicated solution. The second approach is to let the BETA compiler generate Java class files. With this...... approach it is possible to implement plug-ins in BETA and even inherit from Java classes. In the paper the two approaches are described together with part of the mapping from BETA to Java class files. http://www.sciencedirect.com/science/journal/15710661...

  12. COM Support in BETA

    DEFF Research Database (Denmark)

    Madsen, Ole Lehrmann

    1999-01-01

    Component technologies based on binary units of independent production are some of the most important contributions to software architecture and reuse during recent years. Especially the COM technologies and the CORBA standard from the Object Management Group have contributed new and interesting ...... principles for software architecture, and proven to be useful in parctice. In this paper ongoing work with component support in the BETA language is described....

  13. Beta decay for pedestrians

    CERN Document Server

    Lipkin, Harry Jeannot

    1962-01-01

    The ""pedestrian approach"" was developed to describe some essentially simple experimental results and their theoretical implications in plain language. In this graduate-level text, Harry J. Lipkin presents simply, but without oversimplification, the aspects of beta decay that can be understood without reference to the formal theory; that is, the reactions that follow directly from conservation laws and elementary quantum mechanics.The pedestrian treatment is neither a substitute for a complete treatment nor a watered-down version.

  14. Structure and diversity of the T cell antigen receptor beta-chain in a teleost fish.

    Science.gov (United States)

    Partula, S; de Guerra, A; Fellah, J S; Charlemagne, J

    1995-07-15

    Cell-mediated immunity (e.g., allograft rejection) is found in all vertebrates, and these reactions are known to depend on thymus-derived cells in amphibian, avian, and mammalian species. The participation of peripheral T cell-like lymphocytes subpopulations to fish immunity is now well documented, but the developmental origin, migration, and peripheral tissue distribution of these cells remain practically unknown. This is mainly due to the difficulty of efficiently thymectomizing fish at an early stage of development and to the lack of Ab strictly specific for thymocytes and T cell surface Ag. One strategy for analyzing T cell biology in fish would be to characterize the genes encoding polypeptides homologous to the TCR molecules. This report describes cDNA clones from the rainbow trout (Oncorhynchus mykiss) that have sequences very similar to amphibian, avian, and mammalian TCR beta-chains. Three complete trout V beta segments belonging to different families were analyzed; one of them had limited amino acid sequence similarity to the human V beta 20 family. The 10 trout beta-chain-joining segments all retain the invariant mammalian J beta residues, and comparison of 66 V beta-J beta junctions led to the identification of a D beta-like sequence (GGACAGGG) that is shorter than but very similar to the chicken D beta and mammalian D beta 1 sequences. There is considerable diversity at the V beta-D beta and D beta-J beta junctions, suggesting the presence of N-nucleotides. The trout C beta extracellular domain is shorter than mammalian C beta, and the hinge region has no cysteine residue. The transmembrane C beta domain contains a lysine residue that in mammals is thought to be involved in charged interactions with members of the CD3 complex. PMID:7608547

  15. STRENGTH DETERMINATION OF ALUMINIUM AT DIFFERENT TEMPRATURES

    Directory of Open Access Journals (Sweden)

    Deepak Sharma

    2011-08-01

    Full Text Available The necking of specimen is specifically related to thedecrease in cross section when specimen is subjected totensile strength greater than ultimate tensile strength(UTS. The strain distribution no longer hold uniformalong the gauge length. As the tensile load is applied, dueto which length of specimen increases but there is decreasein cross section.The present work laid stress on determining the tensileproperties from stress strain curve by tensile testing ofaluminium (specimen at different range of hightemperature The tensile testing is carried out on INSTRONstatic series 600 KN. The specimens were tested atdifferent range of high temperature (Room Temperature -325 degree Celsius. True Stress and strain is calculatedusing the engineering equation. Using the values of truestress and true strain the true stress strain curve wasplotted. The polynomial equation is obtained from eachspecimen curve. The graph is plotted between temperatureand ultimate tensile strength (UTS which indicates thatthe ultimate tensile strength decreases with the increase intemperature.

  16. An Investigation into Node Strength Connectivity Correlation

    Institute of Scientific and Technical Information of China (English)

    SHI Jian-Jun; WANG Yong-Li; HE Da-Ren

    2009-01-01

    We propose investigating the node strength connectivity correlation by a resource-allocation method and the traditional multiple edge method, respectively. A rough analysis suggests that the resource-allocation node strength connectivity correlation is always negative, which is different from the connectivity correlation of the traditional multiple edge node strength (it can show either positive, negative or no correlation). As examples,empirical investigation results for two real world cooperation-competition networks (the 2004 Athens Olympic Games network and the mixed drink network) are presented. We believe that the resource-allocation node strength connectivity correlation can serve as a description of the relative crackajack distribution, which is a complementarity of the traditional multiple edge one.

  17. Dosimetry analysis of distribution radial dose profiles of {sup 90}Sr + {sup 90}Y beta therapy applicators using the MCNP-4C code and radio chromium films; Analise dosimetrica de perfis de distribuicoes radiais de doses relativas de um aplicador de betaterapia de {sup 90}Sr + {sup 90}Y utilizando o codigo MCNP-4C e filmes radiocromicos

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, T.S.; Yoriyaz, H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Fernandes, M.A.R. [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Fac. de Medicina. Servico de Radioterapia; Louzada, M.J.Q. [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Aracatuba, SP (Brazil). Curso de Medicina Veterinaria

    2010-07-01

    Although they are no longer manufactured, the applicators of {sup 90}Sr +{sup 90}Y acquired in the decades of 1990 are still in use, by having half-life of 28.5 years. These applicators have calibration certificate given by their manufacturers, where few have been recalibrated. Thus it becomes necessary to accomplish thorough dosimetry of these applicators. This paper presents a dosimetric analysis distribution radial dose profiles for emitted by an {sup 90}Sr+{sup 90}Y beta therapy applicator, using the MCNP-4C code to simulate the distribution radial dose profiles and radiochromium films to get them experimentally . The results with the simulated values were compared with the results of experimental measurements, where both curves show similar behavior, which may validate the use of MCNP-4C and radiochromium films for this type of dosimetry. (author)

  18. Dosimetry analysis of distributions radials dose profiles of {sup 90}Sr + {sup 90}Y beta therapy applicators using the MCNP-4C code and radio chromium films; Analise dosimetrica de perfis de distribuicoes radias de doses relativas de um aplicador de betaterapia de {sup 90}Sr + {sup 90}Y utilizando o codigo MCNP-4C e filmes radiocromicos

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, Talita S.; Yoriyaz, Helio [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Fernandes, Marco A.R., E-mail: tasallesc@gmail.co [UNESP, Botucatu, SP (Brazil). Faculdade de Medicina. Servico de Radioterapia; Louzada, Mario J.Q. [UNESP, Aracatuba, SP (Brazil). Curso de Medicina Veterinaria

    2011-07-01

    Although they are no longer manufactured, the applicators of {sup 90}Sr + {sup 90}Y acquired in the decades of 1990 are still in use, by having half-life of 28.5 years. These applicators have calibration certificate given by their manufacturers, where few have been re calibrated. Thus it becomes necessary to accomplish thorough dosimetry of these applicators. This paper presents a dosimetric analysis distribution radial dose profiles for emitted by an {sup 90}Sr + {sup 90}Y beta therapy applicator, using the MCNP-4C code to simulate the distribution radial dose profiles and radio chromium films to get them experimentally . The results with the simulated values were compared with the results of experimental measurements, where both curves show similar behavior, which may validate the use of MCNP-4C and radio chromium films for this type of dosimetry. (author)

  19. LHCb: $2\\beta_s$ measurement at LHCb

    CERN Multimedia

    Conti, G

    2009-01-01

    A measurement of $2\\beta_s$, the phase of the $B_s-\\bar{B_s}$ oscillation amplitude with respect to that of the ${\\rm b} \\rightarrow {\\rm c^{+}}{\\rm W^{-}}$ tree decay amplitude, is one of the key goals of the LHCb experiment with first data. In the Standard Model (SM), $2\\beta_s$ is predicted to be $0.0360^{+0.0020}_{-0.0016} \\rm rad$. The current constraints from the Tevatron are: $2\\beta_{s}\\in[0.32 ; 2.82]$ at 68$\\%$CL from the CDF experiment and $2\\beta_{s}=0.57^{+0.24}_{-0.30}$ from the D$\\oslash$ experiment. Although the statistical uncertainties are large, these results hint at the possible contribution of New Physics in the $B_s-\\bar{B_s}$ box diagram. After one year of data taking at LHCb at an average luminosity of $\\mathcal{L}\\sim2\\cdot10^{32}\\rm cm^{-2} \\rm s^{-1}$ (integrated luminosity $\\mathcal{L}_{\\rm int}\\sim 2 \\rm fb^{-1}$), the expected statistical uncertainty on the measurement is $\\sigma(2\\beta_s)\\simeq 0.03$. This uncertainty is similar to the $2\\beta_s$ value predicted by the SM.

  20. Residual Tensile Strength of Plain Concrete Under Tensile Fatigue Loading

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The functional relation between the residual tensile strength of plain concrete and number of cycles was determined. 99 tappered prism specimens of plain concrete were tested under uniaxial tensile fatigue loading. Based on the probability distribution of the residual tensile strength, the empirical expressions of the residual tensile strength corresponding to the number of cycles were obtained. The residual tensile strength attenuating curves can be used to predict the residual fatigue life of the specimen under variable-amplitude fatigue loading. There is a good correlation between residual tensile strength and residual secant elastic modulus.The relationship between the residual secant elastic modulus and number of cycles was also established.

  1. On the spectrum of secondary electrons emitted during nuclear $\\beta^{-}$-decay in few-electron atoms

    CERN Document Server

    Frolov, Alexei M

    2015-01-01

    Ionization of light atoms and ions during nuclear $\\beta^{-}$-decay is considered. We determine the velocity/momentum spectrum of secondary electrons emitted during nuclear $\\beta^{-}$-decay in one-electron tritium atom. The same method can be applied to describe velocity/momentum distributions of secondary electrons emitted from $\\beta^{-}$-decaying few-electron atoms and molecules.

  2. High strength alloys

    Energy Technology Data Exchange (ETDEWEB)

    Maziasz, Phillip James; Shingledecker, John Paul; Santella, Michael Leonard; Schneibel, Joachim Hugo; Sikka, Vinod Kumar; Vinegar, Harold J.; John, Randy Carl; Kim, Dong Sub

    2012-06-05

    High strength metal alloys are described herein. At least one composition of a metal alloy includes chromium, nickel, copper, manganese, silicon, niobium, tungsten and iron. System, methods, and heaters that include the high strength metal alloys are described herein. At least one heater system may include a canister at least partially made from material containing at least one of the metal alloys. At least one system for heating a subterranean formation may include a tublar that is at least partially made from a material containing at least one of the metal alloys.

  3. High strength alloys

    Energy Technology Data Exchange (ETDEWEB)

    Maziasz, Phillip James [Oak Ridge, TN; Shingledecker, John Paul [Knoxville, TN; Santella, Michael Leonard [Knoxville, TN; Schneibel, Joachim Hugo [Knoxville, TN; Sikka, Vinod Kumar [Oak Ridge, TN; Vinegar, Harold J [Bellaire, TX; John, Randy Carl [Houston, TX; Kim, Dong Sub [Sugar Land, TX

    2010-08-31

    High strength metal alloys are described herein. At least one composition of a metal alloy includes chromium, nickel, copper, manganese, silicon, niobium, tungsten and iron. System, methods, and heaters that include the high strength metal alloys are described herein. At least one heater system may include a canister at least partially made from material containing at least one of the metal alloys. At least one system for heating a subterranean formation may include a tubular that is at least partially made from a material containing at least one of the metal alloys.

  4. Power output and efficiency of beta-emitting microspheres

    International Nuclear Information System (INIS)

    Current standard methods to calculate the dose of radiation emitted during medical applications by beta-minus emitting microspheres rely on an over-simplistic formalism. This formalism is a function of the average activity of the radioisotope used and the physiological dimensions of the patient only. It neglects the variation in energy of the emitted beta particle due to self-attenuation, or self-absorption, effects related to the finite size of the sphere. Here it is assumed the sphere is comprised of a pure radioisotope with beta particles being emitted isotropically throughout the material. The full initial possible kinetic energy distribution of a beta particle is taken into account as well as the energy losses due to scattering by other atoms in the microsphere and bremsstrahlung radiation. By combining Longmire’s theory of the mean forward range of charged particles and the Rayleigh distribution to take into account the statistical nature of scattering and energy straggling, the linear attenuation, or self-absorption, coefficient for beta-emitting radioisotopes has been deduced. By analogy with gamma radiation transport in spheres, this result was used to calculate the rate of energy emitted by a beta-emitting microsphere and its efficiency. Comparisons to standard point dose kernel formulations generated using Monte Carlo data show the efficacy of the proposed method. Yttrium-90 is used as a specific example throughout, as a medically significant radioisotope, frequently used in radiation therapy for treating cancer. - Highlights: • Range-energy relationship for the beta particles in yttrium-90 is calculated. • Formalism for the semi-analytical calculation of self-absorption coefficients. • Energy-dependent self-absorption coefficient calculated for yttrium-90. • Flux rate of beta particles from a self-attenuating radioactive sphere is shown. • The efficiency of beta particle emitting radioactive microspheres is calculated

  5. Statistical Analysis of Data for Timber Strengths

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2003-01-01

    Statistical analyses are performed for material strength parameters from a large number of specimens of structural timber. Non-parametric statistical analysis and fits have been investigated for the following distribution types: Normal, Lognormal, 2 parameter Weibull and 3-parameter Weibull. The...

  6. Atualizações sobre beta-hidroxi-beta-metilbutirato: suplementação e efeitos sobre o catabolismo de proteínas New findings on beta-hydroxy-beta-methylbutyirate: supplementation and effects on the protein catabolism

    Directory of Open Access Journals (Sweden)

    Everson Araújo Nunes

    2008-04-01

    Full Text Available O beta-hidroxi-beta-metilbutirato, metabólito do aminoácido leucina, vem sendo utilizado como suplemento alimentar, em situações específicas, com o intuito de aumentar ou manter a massa isenta de gordura. Os relatos dos efeitos do beta-hidroxi-beta-metilbutirato em estudos recentes fizeram crescer as expectativas sobre sua utilização em casos patológicos. Também foram demonstrados melhores resultados, quando da sua ingestão, no treinamento de força em indivíduos iniciantes e em idosos. Em humanos o beta-hidroxi-beta-metilbutirato tem sido usado como agente anti-catabólico, e em modelos animais foi demonstrado ser eficaz em inibir a atividade de vias proteolíticas em células musculares de indivíduos caquéticos in vitro e in vivo. Os mecanismos participantes desses processos envolvem: a inibição da atividade do sistema ubiquitina proteossoma ATP-dependente, a inibição de vias de sinalização com participação da proteína quinase C-alfa e a diminuição da concentração citoplasmática do fator nuclear - kappa B livre, eventos relacionados ao decréscimo da proteólise em células musculares.The leucine metabolite beta-hydroxy-beta-methylbutyrate has been used as a nutritional supplement in specific situations to prevent losing or to increase lean mass. Recent studies showed interesting results of beta-hydroxy-beta-methylbutyrate supplementation in certain disease states. Better results have also been demonstrated when it is taken by starters or old individuals doing strength training. In humans, beta-hydroxy-beta-methylbutyrate has been used as an anticatabolic agent and in animal models it has been demonstrated to be effective in inhibiting the activity of the proteolytic pathways in muscle cells of extremely weak individuals in vivo and in vitro. The mechanisms that participate in this process involve: inhibition of the ATP-ubiquitin-proteasome pathway, inhibition of the signalization pathways involving protein kinase C

  7. The Strength of Varying Tie Strength

    CERN Document Server

    Bruggeman, Jeroen

    2012-01-01

    "The Strength of Weak Ties" argument (Granovetter 1973) says that the most valuable information is best collected through bridging ties with other social circles than one's own, and that those ties tend to be weak. Aral and Van Alstyne (2011) added that to access complex information, actors need strong ties ("high bandwidth") instead. These insights I generalize by pointing at actors' interest to avoid spending large resources on low value information. Weak ties are well-suited for relatively simple information at low transmission and tie maintenance costs, whereas for complex information, the best outcomes are expected for those actors who vary their bandwidths along with the value of information accessed. To support my claim I use all patents in the USA (two million) over the period 1975-1999. I also show that in rationalized fields, such as technology, bandwidth correlates highly with the value of information, which provides support for using this proxy if value can't be measured directly. Finally, I show ...

  8. Gamow-Teller strength in deformed nuclei within the self-consistent charge-exchange quasi-particle random-phase approximation with the Gogny force

    CERN Document Server

    Martini, M; Goriely, S

    2014-01-01

    The charge-exchange excitations in nuclei are studied within the fully self-consistent proton-neutron quasiparticle random-phase approximation using the finite-range Gogny interaction. No additional parameters beyond those included in the effective nuclear force are included. Axially symmetric deformations are consistently taken into account, both in the description of the ground states and spin-isospin excitations. We focus on the isobaric analog and Gamow-Teller resonances. A comparison of the predicted strength distributions to the existing experimental data is presented and the role of nuclear deformation analyzed. The Gamow-Teller strength is used to estimate the beta-decay half-life of nuclei for which experimental data exist. A satisfactory agreement with experimental half-lives is found and justifies the additional study of the exotic neutron-rich N=82, 126 and 184 isotonic chains of relevance for the r-process nucleosynthesis.

  9. Effect of chord can length on strength of T joints

    Energy Technology Data Exchange (ETDEWEB)

    Madros, M.S.Z.; Zettlemoyer, N.; Healy, B.E.

    1995-12-01

    A study has been conducted to examine the influence of can length on the static strength of compression loaded T-joints. Finite Element models of the T-joints are developed and analyzed using the SESAM/Pretube, PATRAN{reg_sign}, and ABAQUS{trademark} computer programs. The ultimate loads from the analyses are compared with recommended values in API (1993) and other codes. In general, it appears that the API recommended ultimate strength values for T joints with low {beta} should be modified. Also, the API derating equation for X joints with short cans is conservative for T joints. However, a derating equation is required for T joints.

  10. Development of transparent polycrystalline beta-silicon carbide

    Science.gov (United States)

    Bayya, Shyam S.; Villalobos, Guillermo R.; Hunt, Michael P.; Sanghera, Jasbinder S.; Sadowski, Bryan M.; Aggarwal, Ishwar D.; Cinibulk, Michael; Carney, Carmen; Keller, Kristin

    2013-09-01

    Transparent beta-SiC is of great interest because its high strength, low coefficient of thermal expansion, very high thermal conductivity, and cubic crystal structure give it a very high thermal shock resistance. A transparent, polycrystalline beta-SiC window will find applications in armor, hypersonic missiles, and thermal control for thin disc lasers. SiC is currently available as either small transparent vapor grown disks or larger opaque shapes. Neither of which are useful in window applications. We are developing sintering technology to enable transparent SiC ceramics. This involves developing procedures to make high purity powders and studying their densification behavior. We have been successful in demonstrating transparency in thin sections using Field Assisted Sintering Technology (FAST). This paper will discuss the reaction mechanisms in the formation of beta-SiC powder and its sintering behavior in producing transparent ceramics.

  11. The complexation of lanthanides by azo-. beta. -diketones stability constants

    Energy Technology Data Exchange (ETDEWEB)

    Zabra, A.M.; Ramadian, A.A.I.; El-Shetary, B.A.; Abdel-Moez, M.S.

    1982-03-01

    In the present investigation the overall stability constants of an interest tridentate organic ligands and tervalent lanthanide ions have been measured potentiometrically. The stability constants of the complexes between the trivalent lanthanide series of cations and series of azo-..beta..-diketone ligands are reported. The measurements were conducted at 30/sup 0/ at an ionic strength of zero, in 100% methanol. The relation between the overall stability constant (log ..beta../sub 2/) and atomic number of the lanthanide elements, shows a buffer zone at the gadolinium area. The relation between (log ..beta../sub 2/) and the basicity of the studied ligands (..sigma..pK's) are also, discussed. The overall stability values obtained reflected a great affinity of the organic ligands for chelation with lanthanide ions.

  12. Kernel Oriented Generator Distribution

    OpenAIRE

    Bekker, A.; Arashi, M.

    2014-01-01

    Matrix variate beta (MVB) distributions are used in different fields of hypothesis testing, multivariate correlation analysis, zero regression, canonical correlation analysis and etc. In this approach a unified methodology is proposed to generate matrix variate distributions by combining the kernel of MVB distributions of different types with an unknown Borel measurable function of trace operator over matrix space, called generator component. The latter component is a principal element of the...

  13. Xeroradiography in. beta. -thalassaemia

    Energy Technology Data Exchange (ETDEWEB)

    Scutellari, P.N.; Orzincolo, C.; Tamarozzi, R.

    1985-01-01

    Xeroradiographic investigations of the skull, hand, and elbow were performed on 27 patients with homozygous ..beta..-thalassaemia. The results were compared with plain radiographic examinations. Xeroradiography, because of its technical properties (i.e. edge contrast enhancement and wide latitude), was shown to demonstrate cortical thinning of long bones, swelling of the diploic space in the skull, and reticulated patterns in the elbow better than standard radiography. Moreover, the use of 'positive' mode imaging was shown to have advantages in the study of the skull and extremities.

  14. Realized Beta GARCH

    DEFF Research Database (Denmark)

    Hansen, Peter Reinhard; Lunde, Asger; Voev, Valeri Radkov

    2014-01-01

    particularly useful for modeling financial returns during periods of rapid changes in the underlying covariance structure. When applied to market returns in conjunction with returns on an individual asset, the model yields a dynamic model specification of the conditional regression coefficient that is known as...... conditional beta series during the financial crises.......We introduce a multivariate generalized autoregressive conditional heteroskedasticity (GARCH) model that incorporates realized measures of variances and covariances. Realized measures extract information about the current levels of volatilities and correlations from high-frequency data, which is...

  15. Clenbuterol, a beta(2)-agonist, retards atrophy in denervated muscles

    Science.gov (United States)

    Zeman, Richard J.; Ludemann, Robert; Etlinger, Joseph D.

    1987-01-01

    The effects of a beta(2) agonist, clenbuterol, on the protein content as well as on the contractile strength and the muscle fiber cross-sectional area of various denervated muscles from rats were investigated. It was found that denervated soleus, anterior tibialis, and gastrocnemius muscles, but not the extensor digitorum longus, of rats treated for 2-3 weeks with clenbuterol contained 95-110 percent more protein than denervated controls. The twofold difference in the protein content of denervated solei was paralleled by similar changes in contractile strength and muscle fiber cross-sectional area.

  16. Dynamic force spectroscopy to probe adhesion strength of living cells

    OpenAIRE

    Prechtel, K.; Bausch, A. R.; Marchi-Artzner, V.; Kantlehner, M.; Kessler, H; Merkel, R

    2002-01-01

    We studied the mechanical strength of the adhesion of living cells to model membranes. The latter contained a RGD lipopeptide which is a high affinity binding site for a cell adhesion molecule (integrin alpha(V)beta(3)). Cells adhered specifically to the vesicles. We used micropipette aspiration for breaking this adhesion with well defined forces. Systematic variation of the rate of force application revealed pronounced kinetic effects. The dependence of the detachment forces on the loading r...

  17. Beta particle dose rates to micro-organisms in soil

    International Nuclear Information System (INIS)

    Studies were made to estimate the beta-particle dose rates to micro-organisms of various sizes in soil. The small insects and organisms living in soil are constantly exposed to beta-radiation arising from naturally occuring radionuclides in soil as in this case no overlying tissue shields them. The technique of measuring beta-particle dose rate consisted of using of a thin plastic scintillator to measure the pulse height distribution as the beta particle traverses the scintillator. The integrated response was determined by the number and size of the photomultiplier pulses. From the data of soil analyses it was estimated that typically about 29% of the beta particles emitted per gm. of soil were contributed by the U/Ra series, 21% by the Th series and about 50% by potassium. By combining the individual spectra of these three radionuclides in the proportion found in a typical soil, a resultant spectrum was computed representing the energy distribution of the beta particles. The dose rate received by micro-organisms of different shape and size in soil was derived from the equilibrium dose rates combined with a 'Geometrical Factor' of the organisms. For small organisms, the dose rates did not vary between the spherical and cylindrical types, but in the case of larger organisms, the dose rates were found to be greater for the spherical types of the same diameter. (auth.)

  18. Power output and efficiency of beta-emitting microspheres

    Science.gov (United States)

    Cheneler, David; Ward, Michael

    2015-01-01

    Current standard methods to calculate the dose of radiation emitted during medical applications by beta-minus emitting microspheres rely on an over-simplistic formalism. This formalism is a function of the average activity of the radioisotope used and the physiological dimensions of the patient only. It neglects the variation in energy of the emitted beta particle due to self-attenuation, or self-absorption, effects related to the finite size of the sphere. Here it is assumed the sphere is comprised of a pure radioisotope with beta particles being emitted isotropically throughout the material. The full initial possible kinetic energy distribution of a beta particle is taken into account as well as the energy losses due to scattering by other atoms in the microsphere and bremsstrahlung radiation. By combining Longmire's theory of the mean forward range of charged particles and the Rayleigh distribution to take into account the statistical nature of scattering and energy straggling, the linear attenuation, or self-absorption, coefficient for beta-emitting radioisotopes has been deduced. By analogy with gamma radiation transport in spheres, this result was used to calculate the rate of energy emitted by a beta-emitting microsphere and its efficiency. Comparisons to standard point dose kernel formulations generated using Monte Carlo data show the efficacy of the proposed method. Yttrium-90 is used as a specific example throughout, as a medically significant radioisotope, frequently used in radiation therapy for treating cancer.

  19. Double beta decay: present status

    OpenAIRE

    Barabash, A. S.

    2008-01-01

    The present status of double beta decay experiments (including the search for $2\\beta^{+}$, EC$\\beta^{+}$ and ECEC processes) are reviewed. The results of the most sensitive experiments are discussed. Average and recommended half-life values for two-neutrino double beta decay are presented. Conservative upper limits on effective Majorana neutrino mass and the coupling constant of the Majoron to the neutrino are established as $ < 0.75$ eV and $ < 1.9 \\cdot 10^{-4}$, respectively. Proposals fo...

  20. Simultaneous beta and gamma spectroscopy

    Science.gov (United States)

    Farsoni, Abdollah T.; Hamby, David M.

    2010-03-23

    A phoswich radiation detector for simultaneous spectroscopy of beta rays and gamma rays includes three scintillators with different decay time characteristics. Two of the three scintillators are used for beta detection and the third scintillator is used for gamma detection. A pulse induced by an interaction of radiation with the detector is digitally analyzed to classify the type of event as beta, gamma, or unknown. A pulse is classified as a beta event if the pulse originated from just the first scintillator alone or from just the first and the second scintillator. A pulse from just the third scintillator is recorded as gamma event. Other pulses are rejected as unknown events.

  1. The Standard Model and the neutron beta-decay

    CERN Document Server

    Abele, H

    2000-01-01

    This article reviews the relationship between the observables in neutron beta-decay and the accepted modern theory of particle physics known as the Standard Model. Recent neutron-decay measurements of various mixed American-British-French-German-Russian collaborations try to shed light on the following topics: the coupling strength of charged weak currents, the universality of the electroweak interaction and the origin of parity violation.

  2. Scintillator based beta batteries

    Science.gov (United States)

    Rensing, Noa M.; Tiernan, Timothy C.; Shirwadkar, Urmila; O'Dougherty, Patrick; Freed, Sara; Hawrami, Rastgo; Squillante, Michael R.

    2013-05-01

    Some long-term, remote applications do not have access to conventional harvestable energy in the form of solar radiation (or other ambient light), wind, environmental vibration, or wave motion. Radiation Monitoring Devices, Inc. (RMD) is carrying out research to address the most challenging applications that need power for many months or years and which have undependable or no access to environmental energy. Radioisotopes are an attractive candidate for this energy source, as they can offer a very high energy density combined with a long lifetime. Both large scale nuclear power plants and radiothermal generators are based on converting nuclear energy to heat, but do not scale well to small sizes. Furthermore, thermo-mechanical power plants depend on moving parts, and RTG's suffer from low efficiency. To address the need for compact nuclear power devices, RMD is developing a novel beta battery, in which the beta emissions from a radioisotope are converted to visible light in a scintillator and then the visible light is converted to electrical power in a photodiode. By incorporating 90Sr into the scintillator SrI2 and coupling the material to a wavelength-matched solar cell, we will create a scalable, compact power source capable of supplying milliwatts to several watts of power over a period of up to 30 years. We will present the latest results of radiation damage studies and materials processing development efforts, and discuss how these factors interact to set the operating life and energy density of the device.

  3. Strength and tempo of directional selection in the wild

    OpenAIRE

    Hoekstra, H. E.; Hoekstra, J.M.; Berrigan, D.; Vignieri, S. N.; Hoang, A.; Hill, C. E.; Beerli, P; Kingsolver, J. G.

    2001-01-01

    Directional selection is a major force driving adaptation and evolutionary change. However, the distribution, strength, and tempo of phenotypic selection acting on quantitative traits in natural populations remain unclear across different study systems. We reviewed the literature (1984–1997) that reported the strength of directional selection as indexed by standardized linear selection gradients (β). We asked how strong are viability and sexual selection, and whether strength of selection is ...

  4. Hand grip strength

    DEFF Research Database (Denmark)

    Frederiksen, Henrik; Gaist, David; Petersen, Hans Christian;

    2002-01-01

    in life is a major problem in terms of prevalence, morbidity, functional limitations, and quality of life. It is therefore of interest to find a phenotype reflecting physical functioning which has a relatively high heritability and which can be measured in large samples. Hand grip strength is known......Physical functioning late in life has been shown to be affected by genetic factors. Only a few genetic variants have been suggested to be associated with physical functioning, and this only in selected populations (e.g., young healthy males and elite athletes). Declining physical functioning late......-55%). A powerful design to detect genes associated with a phenotype is obtained using the extreme discordant and concordant sib pairs, of whom 28 and 77 dizygotic twin pairs, respectively, were found in this study. Hence grip strength is a suitable phenotype for identifying genetic variants of importance...

  5. Gaussian Discriminating Strength

    OpenAIRE

    Rigovacca, Luca; Farace, Alessandro; De Pasquale, Antonella; Giovannetti, Vittorio

    2015-01-01

    We present a quantifier of non-classical correlations for bipartite, multi-mode Gaussian states. It is derived from the Discriminating Strength measure, introduced for finite dimensional systems in A. Farace et al., New. J. Phys. 16, 073010 (2014). As the latter the new measure exploits the Quantum Chernoff Bound to gauge the susceptibility of the composite system with respect to local perturbations induced by unitary gates extracted from a suitable set of allowed transformations (the latter ...

  6. Strength Pada Amalgam

    OpenAIRE

    Sri Handayani

    2008-01-01

    Amalgam didefinisikan sebagai campuran dari dua atau beberapa logam (alloy) yang salah satunya adalali merkuri. Dental amalgam sendiri merupakan campuran dari merkuri (Hg), perak (Ag), timah (Sn), tembaga (Cu) dan bahan-bahan lain yang memiliki fungsinya masing-masing, dimana sebagian diantaranya akan saling mengatasi kekurangan yang ditimbulkan logam lain, jika logam tersebut dikombinasikan dengan perbandingan yang tepat. Amalgam mempunyai strength (kekuatan) yang cukup besar sehingga dap...

  7. Nonthermally Dominated Electron Acceleration during Magnetic Reconnection in a Low-beta Plasma

    OpenAIRE

    Li, Xiaocan; Guo, Fan; Hui LI; Li, Gang

    2015-01-01

    By means of fully kinetic simulations, we investigate electron acceleration during magnetic reconnection in a nonrelativistic proton--electron plasma with conditions similar to solar corona and flares. We demonstrate that reconnection leads to a nonthermally dominated electron acceleration with a power-law energy distribution in the nonrelativistic low-$\\beta$ regime but not in the high-$\\beta$ regime, where $\\beta$ is the ratio of the plasma thermal pressure and the magnetic pressure. The ac...

  8. Total absorption γ-ray spectroscopy of beta delayed neutron emitters

    Science.gov (United States)

    Valencia, E.; Algora, A.; Tain, J. L.; Rice, S.; Agramunt, J.; Zakari-Issoufou, A.-A.; Porta, A.; Fallot, M.; Jordan, M. D.; Molina, F.; Estevez, E.; Bowry, M.; Bui, V. M.; Caballero-Folch, R.; Cano-Ott, D.; Eloma, V.; Eronen, T.; Garcia, A.; Gomez-Hornillos, M. B.; Gorlychev, V.; Hakala, J.; Jokinen, A.; Kondev, F. G.; Martinez, T.; Moore, I.; Rissanen, J.; Ńystö, J.; Penttilä, H.; Kankainen, A.; Rubio, B.; Gelletly, W.; Perez, A.; Podolyak, Zs.; Regan, P. H.; Farrelly, G. F.; Weber, C.; Mendoza, E.; Igisol People

    2013-06-01

    Preliminary results of the data analysis of the beta decay of 94Rb using a novel - segmented- total absorption spectrometer are shown in this contribution. This result is part of a systematic study of important contributors to the decay heat problem in nuclear reactors. In this particular case the goal is to determine the beta intensity distribution below the neutron separation energy and the gamma/beta competition above.

  9. High beta-Lactamase Levels Change the Pharmacodynamics of beta-Lactam Antibiotics in Pseudomonas aeruginosa Biofilms

    DEFF Research Database (Denmark)

    Wang, Hengzhuang; Ciofu, Oana; Yang, Liang;

    2013-01-01

    , microtiter plates, and on alginate beads were treated with different concentrations of ceftazidime and imipenem. The kinetics of antibiotics on the biofilms was investigated in vitro by time-kill methods. Time-dependent killing of ceftazidime was observed in PAO1 biofilms, but concentration-dependent killing......Resistance to beta-lactam antibiotics is a frequent problem in Pseudomonas aeruginosa lung infection of cystic fibrosis (CF) patients. This resistance is mainly due to the hyperproduction of chromosomally encoded beta-lactamase and biofilm formation. The purpose of this study was to investigate the...... activity of ceftazidime was observed for beta-lactamase-overproducing biofilms of P. aeruginosa in all three models. Ceftazidime showed time-dependent killing on planktonic PAO1 and PA Delta DDh2Dh3. This difference is probably due to the special distribution and accumulation in the biofilm matrix of beta...

  10. An Extended Pareto Distribution

    Directory of Open Access Journals (Sweden)

    Mohamad Mead

    2014-10-01

    Full Text Available For the first time, a new continuous distribution, called the generalized beta exponentiated Pareto type I (GBEP [McDonald exponentiated Pareto] distribution, is defined and investigated. The new distribution contains as special sub-models some well-known and not known distributions, such as the generalized beta Pareto (GBP [McDonald Pareto], the Kumaraswamy exponentiated Pareto (KEP, Kumaraswamy Pareto (KP, beta exponentiated Pareto (BEP, beta Pareto (BP, exponentiated Pareto (EP and Pareto, among several others. Various structural properties of the new distribution are derived, including explicit expressions for the moments, moment generating function, incomplete moments, quantile function, mean deviations and Rényi entropy. Lorenz, Bonferroni and Zenga curves are derived. The method of maximum likelihood is proposed for estimating the model parameters. We obtain the observed information matrix. The usefulness of the new model is illustrated by means of two real data sets. We hope that this generalization may attract wider applications in reliability, biology and lifetime data analysis.

  11. Synthesis of plastic scintillation microspheres: Alpha/beta discrimination

    International Nuclear Information System (INIS)

    Plastic scintillation microspheres (PSm) have been developed as an alternative for liquid scintillation cocktails due to their ability to avoid the mixed waste, besides other strengths in which the possibility for alpha/beta discrimination is included. The aim of this work was to evaluate the capability of PSm containing two combinations of fluorescence solutes (PPO/POPOP and pT/Bis-MSB) and variable amounts of a second organic solvent (naphthalene) to enhance the alpha/beta discrimination. Two commercial detectors with different Pulse Shape Discrimination performances (Quantulus and Triathler) were used to evaluate the alpha/beta discrimination. An optimal discrimination of alpha/beta particles was reached, with very low misclassification values (2% for beta particles and 0.5% for alpha particles), when PSm containing PPO/POPOP and between 0.6 and 2.0 g of naphthalene were evaluated using Triathler and the appropriate programme for data processing. - Highlights: • Plastic scintillation microspheres for α/β discrimination have been synthesised. • The energy transfer process in PSm with different compositions has been investigated. • The α/β discrimination capabilities of two commercial detectors have been evaluated. • 2% and 0.5% of misclassifications for β and α radionuclides have been achieved respectively

  12. A stochastic model of wealth distribution

    CERN Document Server

    Bose, I; Bose, Indrani; Banerjee, Subhasis

    2005-01-01

    We propose a stochastic model of evolution of wealth in a society of economic agents. In the model, an agent can be in two states: inactive and active. Transitions between the states occur at random time intervals. In the active state, the rate at which wealth increases is greater than that in the inactive state. In both the states, wealth diminishes at a rate proportional to the current wealth. The probability density function describing the wealth distribution in the steady state is found to have the form of a beta distribution. Wealth distributions for the poor, middle and the rich classes are obtained separately. In economic literature, beta distribution and its generalisations, namely, the generalised beta distribution functions have been proposed to describe the income distributions of different economic societies. Our stochastic model provides a simple basis for the appearance of beta-type distributions.

  13. BETA SPECTRA. I. Negatrons spectra

    International Nuclear Information System (INIS)

    Using the Fermi theory of beta decay, the beta spectra for 62 negatrons emitters have been computed introducing a correction factor for unique forbidden transitions. These spectra are plotted vs. energy, once normal i sed, and tabulated with the related Fermi functions. The average and median energies are calculated. (Author)

  14. The best-beta CAPM

    NARCIS (Netherlands)

    L. Zou

    2006-01-01

    The issue of 'best-beta' arises as soon as potential errors in the Sharpe-Lintner-Black capital asset pricing model (CAPM) are acknowledged. By incorporating a target variable into the investor preferences, this study derives a best-beta CAPM (BCAPM) that maintains the CAPM's theoretical appeal and

  15. Beta-delayed fission probabilities of transfermium nuclei, involved in the r-process

    Science.gov (United States)

    Panov, I.; Lutostansky, Yu; Thielemann, F.-K.

    2016-01-01

    For the nucleosynthesis of heavy and superheavy nuclei fission becomes very important when the r-process runs in a very high neutron density environment. In part, fission is responsible for the formation of heavy nuclei due to the inclusion of fission products as new seed nuclei (fission cycling). More than that, beta-delayed fission, along with spontaneous fission, is responsible in the late stages of the r-process for the suppression of superheavy element yields. For beta-delayed fission probability calculations a model description of the beta-strength- functions is required. Extended theoretical predictions for astro-physical applications were provided long ago, and new predictions also for superheavy nuclei with uptodate nuclear input are needed. For the further extension of data to heavier transactinides the models of strength- functions should be modified, taking into account more complicated level schemes. In our present calculations the strength-function model is based on the quasi-particle approximation of Finite Fermi Systems Theory. The probabilities of beta-delayed fission and beta-delayed neutron emission are calculated for some transfermium neutron-rich nuclei, and the influence of beta-delayed fission upon superheavy element formation is discussed.

  16. Stress-strength models for system reliability

    International Nuclear Information System (INIS)

    Modeling and statistical inference for the reliability of a system consisting of several components where the operating environment interferes with the performance of the system is examined. Specifically, the situation is considered where a k-component system functions when at least s(1 less than or equal to s less than or equal to k) of the components survive a shock of a random magnitude that comes into play. Under the ''equal component'' model, the strengths of the components are assumed to be independent and identically distributed random variables with c.d.f. G(x) and the common stress is a random variable having the c.d.f. F(y). The reliability of such a system is then a functional of the pair (F,G). The study includes a presentation of the uniformly minimum variance unbiased estimator of reliability under a nonparametric setting, associated large sample theory and followed by an evaluation of asymptotic relative efficiency. The model formulation is then extended to allow nonidentical strength distributions for the components and methods of estimation of reliability are also investigated in this context. Finally, another formulation is treated where each component has its own strength distribution and each is subjected to an independent stress from possibly different stress distributions. The relation to system reliability studies using binomial data is elucidated

  17. A cartography of K{beta} resonant inelastic X-ray scattering for lifetime-broadening-suppressed spin-selected XANES of {alpha}-Fe{sub 2}O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Hisashi [Department of Chemical and Biological Sciences, Faculty of Science, Japan Women' s University, 2-8-1 Mejirodai, Bunkyo, Tokyo 112-8681 (Japan)], E-mail: hayashih@fc.jwu.ac.jp; Azumi, Tomofumi; Sato, Atsushi; Udagawa, Yasuo [IMRAM, Tohoku University, Katahira 2-1-1, Aoba, Sendai 980-8577 (Japan)

    2008-12-15

    A series of K{beta} resonant inelastic X-ray scattering (RIXS) spectra of {alpha}-Fe{sub 2}O{sub 3} is presented as two-dimensional RIXS maps and analyzed in terms of the Kramers-Heisenberg equation. Genuine lifetime-broadening-suppressed (LBS) spin-selected oscillator strength distributions, which are consistent with Hund's rule, are deduced. It is shown that 2D maps can highlight implications of RIXS results to reveal existences and characteristics of electronic states which are hidden in absorption spectra.

  18. Beta Beams Implementation at CERN

    CERN Document Server

    Hansen, Christian

    2011-01-01

    Beta Beam,the concept of generating a pure and intense (anti) neutrino beam by letting accelerated radioactive ions beta decay in a storage ring, called Decay Ring (DR), is the base of one of the proposed next generation neutrino oscillation facilities, necessary for a complete study of the neutrino oscillation parameter space. Sensitivities of the unknown neutrino oscillation parameters depend on the Decay Ring's ion intensity and of it's duty factor (the filled ratio of the ring). Therefore efficient ion production, stripping, bunching, acceleration and storing are crucial sub-projects under study and development within the Beta Beam collaboration. Specifically the feasibility of these tasks as parts of a Beta Beam implementation at CERN will be discussed in this report. The positive impact of the large {\\theta}13 indications from T2K on the Beta Beam performance will also be discussed.

  19. The (t,3He) and (3He,t) reactions as probes of Gamow-Teller strength

    CERN Document Server

    Zegers, R G T; Austin, S M; Bazin, D; Berg, G P A; Brown, B A; Cole, A L; Daito, I; Fujita, Y; Fujiwara, M; Galès, Sydney; Harakeh, M N; Hashimoto, H; Hayami, R; Hitt, G W; Howard, M E; Itoh, M; Jänecke, J; Kawabata, T; Kawase, K; Kinoshita, M; Nakamura, T; Nakanishi, K; Nakayama, S; Okamura, S; Richter, W A; Roberts, D A; Sherrill, B M; Shimbara, Y; Steiner, M; Uchida, M; Ueno, H; Van den Berg, A M; Yamagata, T; Yosoi, M; Austin, Sam M.

    2006-01-01

    Charge-exchange reactions are an important tool for determining weak-interaction rates. They provide stringent tests for nuclear structure models necessary for modeling astrophysical environments such as neutron stars and core-collapse supernovae. In this paper we demonstrate via a study of 26Mg(t,3He) that the (t,3He) reaction at 115 MeV/nucleon is an accurate probe for extracting Gamow-Teller strengths. This study is complemented by 26Mg(3He,t) data taken at 140 MeV/nucleon which allows for a comparison of T=2 analog states excited via the mirror reactions. A good correspondence is found between Gamow-Teller distributions measured via the 26Mg(3He,t) and 26Mg(p,n) experiments, indicating probe-independence of the strength extraction. Results from 26Mg(t,3He) and 26Mg(d,2He) also display good correspondence, showing that with the (t,3He) reaction a new tool has become available for studying Gamow-Teller strengths in the beta+ direction. Furthermore, we test shell-model calculations using the new USD-05B inte...

  20. Intuitionistic Fuzzy Generalized Beta Closed Mappings

    OpenAIRE

    D. Jayanthi

    2014-01-01

    In this paper we introduce intuitionistic fuzzy generalized beta closed mappings and intuitionistic fuzzy generalized beta open mappings. We investigate some of their properties. We also introduce intuitionistic fuzzy M-generalized beta closed mappings as well as intuitionistic fuzzy M-generalized beta open mappings. We provide the relation between intuitionistic fuzzy M-generalized beta closed mappings and intuitionistic fuzzy generalized beta closed mappings.

  1. Derivatives of the Incomplete Beta Function

    Directory of Open Access Journals (Sweden)

    Robert J. Boik

    1998-03-01

    Full Text Available The incomplete beta function is defined as where Beta(p, q is the beta function. Dutka (1981 gave a history of the development and numerical evaluation of this function. In this article, an algorithm for computing first and second derivatives of Ix,p,q with respect to p and q is described. The algorithm is useful, for example, when fitting parameters to a censored beta, truncated beta, or a truncated beta-binomial model.

  2. Derivatives of the Incomplete Beta Function

    OpenAIRE

    Robison-Cox, James F.; Robert J. Boik

    1998-01-01

    The incomplete beta function is defined as where Beta(p, q) is the beta function. Dutka (1981) gave a history of the development and numerical evaluation of this function. In this article, an algorithm for computing first and second derivatives of Ix,p,q with respect to p and q is described. The algorithm is useful, for example, when fitting parameters to a censored beta, truncated beta, or a truncated beta-binomial model.

  3. Relation of isospin-symmetry breaking correction for superallowed beta decay to energy of charge-exchange giant monopole resonance

    CERN Document Server

    Rodin, Vadim

    2012-01-01

    Having applied an analytical transformation, a new exact representation for the nuclear isospin-symmetry breaking correction $\\delta_C$ to superallowed beta decay is obtained. The correction is shown to be essentially reciprocal to the square of an energy parameter $\\Omega_M$ which characterizes charge-exchange monopole strength distribution. The proportionality coefficient in this relation is determined by basic properties of the ground state of the even-even mother nucleus, and should be reliably calculated in any realistic nuclear model. Therefore, the single parameter $\\Omega_M$ contains all the information about the properties of excited $0^+$ states needed to describe $\\delta_C$. This parameter can possibly be determined experimentally by charge-exchange reactions. Basic quantities of interest are calculated within the isospin-consistent continuum random phase approximation, and the values of $\\delta_C$ are compared with the corresponding results by other approaches.

  4. Laser heating of thermoluminescent films: Dose mapping applied to beta dosimetry

    DEFF Research Database (Denmark)

    Setzkorn, R.; Prévost, H.; Gasiot, J.; Christensen, P.

    This work addresses radiation dose mapping based on scanning of laser heated thermoluminescent foils used for dose distribution analyses of beta radiation fields. Results are presented from dose homogeneity measurements, determination of depth-dose profile in tissue and studies of energy and...... suitable as extremity dosemeters for monitoring in beta radiation fields....

  5. Changes of laminin beta 2 chain expression in congenital muscular dystrophy

    DEFF Research Database (Denmark)

    Cohn, R D; Herrmann, R; Wewer, U M;

    1997-01-01

    We studied the distribution of laminin beta 2 chain in the skeletal muscle basement membrane of 16 patients with congenital muscular dystrophy (CMD) by immunohistochemistry. A dramatic reduction in the laminin beta 2 staining was observed in four patients with classical merosin-negative CMD. A...

  6. Spatial Double Generalized Beta Regression Models: Extensions and Application to Study Quality of Education in Colombia

    Science.gov (United States)

    Cepeda-Cuervo, Edilberto; Núñez-Antón, Vicente

    2013-01-01

    In this article, a proposed Bayesian extension of the generalized beta spatial regression models is applied to the analysis of the quality of education in Colombia. We briefly revise the beta distribution and describe the joint modeling approach for the mean and dispersion parameters in the spatial regression models' setting. Finally, we…

  7. An atomistic modeling survey of the shear strength of twist grain boundaries in aluminum

    International Nuclear Information System (INIS)

    A computational survey of the shear strength of 343 unique grain boundaries was performed. For each boundary, the strength was surveyed as a function of shear direction. The results suggest that: (1) the shear strength cannot be comprehensively predicted by common grain boundary descriptors, (2) the shear strength depends significantly and simply on shear direction due to the faceted geometry of boundary planes, and (3) grain boundary shear strengths in an ordinary material can be represented by a simple statistical distribution

  8. Optimization of the strength of SOFC anode supports

    DEFF Research Database (Denmark)

    Frandsen, Henrik Lund; Ramos, Tania; Faes, A.;

    2012-01-01

    , such as powder milling and sintering temperature. The strength was measured with the ball-on-ring method, and analyzed with a large displacement finite element model. Weibull statistics were used to describe the distribution of strengths. The influence on the Weibull strength of the many different...... processing parameters was found to be quantifiable in terms of cell porosity to a large extent. The results were validated with an independent set of measurements of strength and stiffness by uniaxial tension and the impulse excitation technique, respectively. For application of the finding in relation to...

  9. Granular dynamic shear strength and its influencing factors

    Institute of Scientific and Technical Information of China (English)

    吴爱祥; 孙业志

    2002-01-01

    The granular dynamic shear strength is the same as that of the static one in nature, as found from numerous experiments and investigations. The shear strength is equal to the sum of the internal frictional force and the cohesive force. The influences of type, shape, size distribution, pore ratio, moisture content and variation of vibration velocity on the dynamic shear strength of granules were studied. Based on numerous vibration shear experiments, the authors investigate the mechanism of dynamic shear strength in granules in terms of the fundamental principle and the relevant theory of modern tribology.

  10. High Temperature Stability of Potassium Beta Alumina

    Science.gov (United States)

    Williams, R. M.; Kisor, A.; Ryan, M. A.

    1996-01-01

    None. From Objectives section: Evaluate the stability of potassium beta alumina under potassium AMTEC operating conditions. Evaluate the stability regime in which potassium beta alumina can be fabricated.

  11. Neutron-spectroscopic strength in Ru isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, J.L.M.; Borello-Lewin, T.; Horodynski-Matsushigue, L.B. (Instituto de Fisica da Univrsidade de Sao Paulo, Sao Paulo (Brazil))

    1994-08-01

    A systematic, high resolution (6--8 keV) study of ([ital d],[ital t]) reactions on [sup 100,102,104]Ru is reported. Spectroscopic factors were extracted by comparison of experimental angular distributions with distorted wave Born approximation predictions. All of the information for [sup 99]Ru and, for excitation energies above 0.9 MeV, for [sup 103]Ru is new. Most of the strength expected for the 50--82 neutron shell was found. The strength distributions are discussed, also in comparison with the corresponding stripping reactions. Special attention is focused on extremely low and relatively intense [ital l]=3 excitations and on the [ital l]=4 transfer pattern observed.

  12. A semiconductor beta ray spectrometer

    International Nuclear Information System (INIS)

    Measurement of energy spectra of beta particles emitted from nuclei in beta-decay processes provides information concerning the mass difference of these nuclei between initial and final state. Moreover, experimental beta spectra yield information on the feeding of the levels in the daughter nucleus. Such data are valuable in the construction and checking of the level schemes. This thesis describes the design, construction, testing and usage of a detector for the accurate measurement of the mentioned spectra. In ch. 2 the design and construction of the beta spectrometer, which uses a hyper-pure germanium crystal for energy determination, is described. A simple wire chamber is used to discriminate beta particles from gamma radiation. Disadvantages arise from the large amounts of scattered beta particles deforming the continua. A method is described to minimize the scattering. In ch. 3 some theoretical aspects of data analysis are described and the results of Monte-Carlo simulations of the summation of annihilation radiation are compared with experiments. Ch. 4 comprises the results of the measurements of the beta decay energies of 103-108In. 87 refs.; 34 figs.; 7 tabs

  13. Measuring Tgv Source Strength with Syntacan

    Science.gov (United States)

    van der Toorn, J. D.; Hendriks, H.; van den Dool, T. C.

    1996-05-01

    A 10 m high, vertical synthetic acoustic antenna (Syntacan) has been used to measure the acoustic source strength and the vertical source distribution of a French TGV as a function of the speed of the train, the frequency of the sound and the coach type (passenger coach, power car). The results are intended as input for calculation schemes and reduced scale models that are used to predict sound exposure levels of high speed passenger trains in built-up areas.

  14. Beta Regression Finite Mixture Models of Polarization and Priming

    Science.gov (United States)

    Smithson, Michael; Merkle, Edgar C.; Verkuilen, Jay

    2011-01-01

    This paper describes the application of finite-mixture general linear models based on the beta distribution to modeling response styles, polarization, anchoring, and priming effects in probability judgments. These models, in turn, enhance our capacity for explicitly testing models and theories regarding the aforementioned phenomena. The mixture…

  15. P53 and Beta-Catenin Activity during Estrogen treatment of Osteoblasts

    Directory of Open Access Journals (Sweden)

    Kolman Kevin

    2005-07-01

    Full Text Available Abstract Background This study was undertaken to examine the relationship between the tumor suppressor gene p53 and the nuclear signaling protein beta-catenin during bone differentiation. Cross talk between p53 and beta-catenin pathways has been demonstrated and is important during tumorigenesis and DNA damage, where deregulation of beta catenin activates p53. In this study, we used estrogen treatment of osteoblasts as a paradigm to study the relationship between the two proteins during osteoblast differentiation. Results We exposed osteoblast-like ROS17/2.8 cells to 17-beta estradiol (E2, in a short term assay, and studied the cellular distribution and expression of beta-catenin. We found beta-catenin to be up regulated several fold following E2 treatment. Levels of p53 and its functional activity mirrored the quantitative changes seen in beta-catenin. Alkaline phosphatase, an early marker of osteoblast differentiation, was increased in a manner similar to beta-catenin and p53. In order to determine if there was a direct relationship between alkaline phosphatase expression and beta-catenin, we used two different approaches. In the first approach, treatment with LiCl, which is known to activate beta-catenin, caused a several fold increase in alkaline phosphatase activity. In the second approach, transient transfection of wild type beta-catenin into osteoblasts increased alkaline phosphatase activity two fold over basal levels, showing that beta catenin expression can directly affect alkaline phosphatase expression. However increase in beta catenin activity was not associated with an increase in its signaling activity through TCF/LEF mediated transcription. Immunofluorescence analyses of p53 and beta-catenin localization showed that E2 first caused an increase in cytosolic beta-catenin followed by the accumulation of beta-catenin in the nucleus. Nuclear p53 localization was detected in several cells. Expression of p53 was accompanied by

  16. Effect of beta blockade and beta stimulation on stage fright.

    Science.gov (United States)

    Brantigan, C O; Brantigan, T A; Joseph, N

    1982-01-01

    Stage fright, physiologically the "fight or flight" reaction, is a disabling condition to the professional musician. Because it is mediated by the sympathetic nervous system, we have investigated the effects of beta blockade on musical performance with propranolol in a double blind fashion and the effects of beta stimulation using terbutaline. Stage fright symptoms were evaluated in two trials, which included a total of 29 subjects, by questionnaire and by the State Trai Anxiety Inventory. Quality of musical performance was evaluated by experienced music critics. Beta blockade eliminates the physical impediments to performance caused by stage fright and even eliminates the dry mouth so frequently encountered. The quality of musical performance as judged by experienced music critics is significantly improved. This effect is achieved without tranquilization. Beta stimulating drugs increase stage fright problems, and should be used in performing musicians only after consideration of the detrimental effects which they may have on musical performance. PMID:6120650

  17. The Age of Beta Pic

    OpenAIRE

    Navascues, D. Barrado y; Stauffer, J. R.; Song, I.; Caillault, J-P.

    1999-01-01

    We have reanalyzed data for the proposed moving group associated with beta Pic in order to determine if the group (or part of it) is real, and, if so, to derive an improved age estimate for beta Pic. By using new, more accurate proper motions from PPM and Hipparcos and a few new radial velocities, we conclude that on kinematic grounds, two M dwarfs have space motions that coincide with that of beta Pic to within 1 km/s with small error bars. Based on a CM diagram derived from accurate photome...

  18. Smart Beta or Smart Alpha

    DEFF Research Database (Denmark)

    Winther, Kenneth Lillelund; Steenstrup, Søren Resen

    2016-01-01

    that smart beta investing probably will do better than passive market capitalization investing over time, we believe many are coming to a conclusion too quickly regarding active managers. Institutional investors are able to guide managers through benchmarks and risk frameworks toward the same well...... only superior to the common capitalization weighted index but also to their smart beta benchmark, even after cost for value, size, and low volatility funds. We encourage investors to increase the use of smart beta as benchmarks while still obtaining extra performance through active management—a concept...

  19. Experiments on double beta decay

    Energy Technology Data Exchange (ETDEWEB)

    Busto, J. [Neuchatel Univ. (Switzerland). Inst. de Physique

    1996-11-01

    The Double Beta Decay, and especially ({beta}{beta}){sub 0{nu}} mode, is an excellent test of Standard Model as well as of neutrino physics. From experimental point of view, a very large number of different techniques are or have been used increasing the sensitivity of this experiments quite a lot (the factor of 10{sup 4} in the last 20 years). In future, in spite of several difficulties, the sensitivity would be increased further, keeping the interest of this very important process. (author) 4 figs., 5 tabs., 21 refs.

  20. Dosimetry of {beta} extensive sources; Dosimetria de fuentes {beta} extensas

    Energy Technology Data Exchange (ETDEWEB)

    Rojas C, E.L.; Lallena R, A.M. [Departamento de Fisica Moderna, Universidad de Granada, E-18071 Granada (Spain)

    2002-07-01

    In this work, we have been studied, making use of the Penelope Monte Carlo simulation code, the dosimetry of {beta} extensive sources in situations of spherical geometry including interfaces. These configurations are of interest in the treatment of the called cranealfaringyomes of some synovia leisure of knee and other problems of interest in medical physics. Therefore, its application can be extended toward problems of another areas with similar geometric situation and beta sources. (Author)

  1. Beet necrotic yellow vein virus accumulates inside resting spores and zoosporangia of its vector Polymyxa betae BNYVV infects P. betae

    Directory of Open Access Journals (Sweden)

    Payton Mark

    2007-04-01

    Full Text Available Abstract Background Plasmodiophorids and chytrids are zoosporic parasites of algae and land plant and are distributed worldwide. There are 35 species belonging to the order Plasmodiophorales and three species, Polymyxa betae, P. graminis, and Spongospora subterranea, are plant viral vectors. Plasmodiophorid transmitted viruses are positive strand RNA viruses belonging to five genera. Beet necrotic yellow vein virus (BNYVV and its vector, P. betae, are the causal agents for rhizomania. Results Evidence of BNYVV replication and movement proteins associating with P. betae resting spores was initially obtained using immunofluorescence labeling and well characterized antisera to each of the BNYVV proteins. Root cross sections were further examined using immunogold labeling and electron microscopy. BNYVV proteins translated from each of the four genomic and subgenomic RNAs accumulate inside P. betae resting spores and zoospores. Statistical analysis was used to determine if immunolabelling detected viral proteins in specific subcellular domains and at a level greater than in control samples. Conclusion Virus-like particles were detected in zoosporangia. Association of BNYVV replication and movement proteins with sporangial and sporogenic stages of P. betae suggest that BNYVV resides inside its vector during more than one life cycle stage. These data suggest that P. betae might be a host as well as a vector for BNYVV

  2. Gaussian discriminating strength

    Science.gov (United States)

    Rigovacca, L.; Farace, A.; De Pasquale, A.; Giovannetti, V.

    2015-10-01

    We present a quantifier of nonclassical correlations for bipartite, multimode Gaussian states. It is derived from the Discriminating Strength measure, introduced for finite dimensional systems in Farace et al., [New J. Phys. 16, 073010 (2014), 10.1088/1367-2630/16/7/073010]. As the latter the new measure exploits the quantum Chernoff bound to gauge the susceptibility of the composite system with respect to local perturbations induced by unitary gates extracted from a suitable set of allowed transformations (the latter being identified by posing some general requirements). Closed expressions are provided for the case of two-mode Gaussian states obtained by squeezing or by linearly mixing via a beam splitter a factorized two-mode thermal state. For these density matrices, we study how nonclassical correlations are related with the entanglement present in the system and with its total photon number.

  3. Water's Hydrogen Bond Strength

    CERN Document Server

    Chaplin, Martin

    2007-01-01

    Water is necessary both for the evolution of life and its continuance. It possesses particular properties that cannot be found in other materials and that are required for life-giving processes. These properties are brought about by the hydrogen bonded environment particularly evident in liquid water. Each liquid water molecule is involved in about four hydrogen bonds with strengths considerably less than covalent bonds but considerably greater than the natural thermal energy. These hydrogen bonds are roughly tetrahedrally arranged such that when strongly formed the local clustering expands, decreasing the density. Such low density structuring naturally occurs at low and supercooled temperatures and gives rise to many physical and chemical properties that evidence the particular uniqueness of liquid water. If aqueous hydrogen bonds were actually somewhat stronger then water would behave similar to a glass, whereas if they were weaker then water would be a gas and only exist as a liquid at sub-zero temperature...

  4. Characterization of a beta-catenin nuclear localization defect in MCF-7 breast cancer cells.

    Science.gov (United States)

    Jamieson, Cara; Mills, Kate M; Lui, Christina; Semaan, Crystal; Molloy, Mark P; Sharma, Manisha; Forwood, Jade K; Henderson, Beric R

    2016-02-15

    Beta-catenin plays a key role in transducing Wnt signals from the plasma membrane to the nucleus. Here we characterize an unusual subcellular distribution of beta-catenin in MCF-7 breast cancer cells, wherein beta-catenin localizes to the cytoplasm and membrane but atypically did not relocate to the nucleus after Wnt treatment. The inability of Wnt or the Wnt agonist LiCl to induce nuclear localization of beta-catenin was not due to defective nuclear transport, as the transport machinery was intact and ectopic GFP-beta-catenin displayed rapid nuclear entry in living cells. The mislocalization is explained by a shift in the retention of beta-catenin from nucleus to cytoplasm. The reduced nuclear retention is caused by unusually low expression of lymphoid enhancer factor/T-cell factor (LEF/TCF) transcription factors. The reconstitution of LEF-1 or TCF4 expression rescued nuclear localization of beta-catenin in Wnt treated cells. In the cytoplasm, beta-catenin accumulated in recycling endosomes, golgi and beta-COP-positive coatomer complexes. The peripheral association with endosomes diminished after Wnt treatment, potentially releasing β-catenin into the cytoplasm for nuclear entry. We propose that in MCF-7 and perhaps other breast cancer cells, beta-catenin may contribute to cytoplasmic functions such as ER-golgi transport, in addition to its transactivation role in the nucleus. PMID:26844628

  5. Beta particle monitor for surfaces

    International Nuclear Information System (INIS)

    A beta radiation detector which is capable of reliably detecting beta radiation emitted from a surface. An electrically conductive signal collector is adjustably mounted inside an electrically conductive enclosure which may define a single large opening for placing against a surface. The adjustable mounting of the electrically conductive signal collector can be based on the distance from the surface or on the expected beta energy range. A voltage source is connected to the signal collector through an electrometer or other display means for creating an electric field between the signal collector and the enclosure. Air ions created by the beta radiation are collected and the current produced is indicated on the electrometer or other display means. 2 figs

  6. Peginterferon Beta-1a Injection

    Science.gov (United States)

    ... symptoms such as headaches, bone or muscle aches, fever, chills, and tiredness during your treatment with peginterferon beta- ... not go away: headache muscle or joint pain fever chills weakness Some side effects can be serious. If ...

  7. Beta-gamma discriminator circuit

    International Nuclear Information System (INIS)

    The major difficulty encountered in the determination of beta-ray dose in field conditions is generally the presence of a relatively high gamma-ray component. Conventional dosimetry instruments use a shield on the detector to estimate the gamma-ray component in comparison with the beta-ray component. More accurate dosimetry information can be obtained from the measured beta spectrum itself. At Los Alamos, a detector and discriminator circuit suitable for use in a portable spectrometer have been developed. This instrument will discriminate between gammas and betas in a mixed field. The portable package includes a 256-channel MCA which can be programmed to give a variety of outputs, including a spectral display, and may be programmed to read dose directly

  8. Understanding college students' fruit consumption. Integrating habit strength in the theory of planned behaviour.

    Science.gov (United States)

    de Bruijn, Gert-Jan

    2010-02-01

    The additive and interactive effect of habit strength in the explanation of young adults' fruit consumption was studied within the context of the theory of planned behaviour (TPB). Additionally, behavioural and control beliefs were modelled as predictors of profile membership based on current fruit consumption, motivation and habit strength towards fruit consumption. Cross-sectional data were available from undergraduate students (n=538; mean age=21.19; S.D.=2.57) who completed measures of fruit consumption, habit strength, TPB-concepts, and behavioural and control beliefs. Data were analyzed using stepwise regression analysis, simple slope analysis, and discriminant function analysis. Results showed that, based on a significant intention x habit interaction (beta=.13), the intention-fruit consumption relationship was more than twice as strong at low levels of habit strength (beta=.39) than at high levels of habit strength (beta=.16). Furthermore, beliefs regarding health and weight management were relatively unable to distinguish profiles created from motivation, habit strength and current fruit consumption. Rather, beliefs about controllability of fruit consumption were amongst the most consistent discriminating beliefs. Findings suggest that stronger fruit consumption habits make fruit consumption less intentional and that interventions aiming to increase fruit consumption may need to develop persuasive messages focusing on situational beliefs, rather than emphasizing health outcomes. PMID:19712718

  9. Statistical effects in beta-delayed neutron emission from fission product nuclides

    International Nuclear Information System (INIS)

    The delayed neutron spectra for the precursors Rb-93, 94, 95, 96, 97 and Cs-145 were measured by use of the on-line isotope separator facility TRISTAN and a time-of-flight (TOF) spectrometer. Flight paths were used that provided, for energies below 70 keV, a FWHM energy resolution between 2 and 4 percent. Each spectrum showed discrete neutron peaks below 156 keV, with as many as 26 in the Rb-95 spectra. Level densities near the neutron binding energy in the neutron-emitting nuclide were deduced using a missing-level indicator based on a Porter-Thomas distribution of neutron peak intensities. The resulting level density data were compared to the predictions of the Gilbert and Cameron formulism and to those of Dilg, Schantl, Vonach and Uhl. Comparisons were made between the empirically-based level parameter a and the values predicted by each model for Sr-93, 94, 95, 97 and Ba-145. The two models appear, within the uncertainties, to be equally capable of describing these neutron-rich nuclides and equally as capable for them as they are for nuclides in the valley of beta stability. Measurements of the neutron strength function are sometimes possible with the present TOF system for neutron decays with competing neutron branches to levels in the grandchild nucleus. A value for the d-wave strength function of Sr-96 is found to be (4.2 +- 1.1)/104. Improvements in the TOF system, allowing the measurement of the neutron strength function for the more general case, are discussed. 72 refs., 56 figs., 16 tabs

  10. Recent double beta decay results

    Energy Technology Data Exchange (ETDEWEB)

    Balysh, A. (Kurchatov Institute, 123 182 Moscow (Russian Federation)); Beck, M. (Max-Planck-Institut fuer Kernphysik, W-6900 Heidelberg (Germany)); Belyaev, S.T. (Kurchatov Institute, 123 182 Moscow (Russian Federation)); Bensch, F.; Bockholt, J. (Max-Planck-Institut fuer Kernphysik, W-6900 Heidelberg (Germany)); Demehin, A.; Gurov, A. (Kurchatov Institute, 123 182 Moscow (Russian Federation)); Heusser, G.; Hirsch, M.; Klapdor-Kleingrothaus, H.V. (Max-Planck-Institut fuer Kernphysik, W-6900 Heidelberg (Germany)); Kondratenko, I.; Lebedev, V.I. (Kurchatov Institute, 123 182 Moscow (Russian Federation)); Maier, B. (Max-Planck-Institut fuer Kernphysik, W-6900 Heidelberg (Germany)); Mueller, A. (Istituto Nazionale di Fisica Nucleare LNGS, 67010 Assergi (Italy)); Petry, F.; Piepke, A.; Strecker, H.; Voellinger, M.; Zuber, K. (Max-Planck-Institut fuer Kernphysik, W-6900 Heidelberg (Germany))

    1992-02-01

    The status and recent results of second generation [beta][beta]-experiments using isotopically enriched source materials are described. These experiments are at present the most sensitive tools to distinguish Dirac from Majorana neutrinos. The at present most advanced experimental techniques, namely the use of high-resolution calorimetric detectors and of time projection chambers are compared. New limits on the Majorana neutrino mass as well as for the Majoron-neutrino coupling are presented.

  11. Apollo applications of beta fiber glass

    Science.gov (United States)

    Naimer, J.

    1971-01-01

    The physical characteristics of Beta fiber glass are discussed. The application of Beta fiber glass for fireproofing the interior of spacecraft compartments is described. Tests to determine the flammability of Beta fiber glass are presented. The application of Beta fiber glass for commercial purposes is examined.

  12. Synthesis of Beta Pyridyl Carbinol Tartrate

    Directory of Open Access Journals (Sweden)

    S. K. Shukla

    1968-04-01

    Full Text Available A process for the synthesis of Beta pyridine carboxylic acid ethy1 ester starting from quinoline has been developed. Beta-pyridine carboxylic acid ethy1 ester on reduction with lithium aluminium hydride gave Beta-pyridy1 carbinol which on treatment tartaric acid yielded Beta-pyridy1 carbinol tartrate, a vaso dilator known in trade as "Ronicoltartrate".

  13. Index distribution of gaussian random matrices.

    Science.gov (United States)

    Majumdar, Satya N; Nadal, Céline; Scardicchio, Antonello; Vivo, Pierpaolo

    2009-11-27

    We compute analytically, for large N, the probability distribution of the number of positive eigenvalues (the index N+) of a random N x N matrix belonging to Gaussian orthogonal (beta=1), unitary (beta=2) or symplectic (beta=4) ensembles. The distribution of the fraction of positive eigenvalues c=N+/N scales, for large N, as P(c,N) approximately = exp[-betaN(2)Phi(c)] where the rate function Phi(c), symmetric around c=1/2 and universal (independent of beta), is calculated exactly. The distribution has non-Gaussian tails, but even near its peak at c=1/2 it is not strictly Gaussian due to an unusual logarithmic singularity in the rate function. PMID:20366083

  14. PET imaging of dopamine transporters in the human brain using [{sup 11}C]-{beta}-CPPIT, a cocaine derivative lacking the 2{beta}-ester function

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbaechler, Roland D.; Gucker, Pascale M.; Arigoni, Michele; Kneifel, Stefan; Vollenweider, Franz X.; Buck, Alfred; Burger, Cyrill; Berthold, Thomas; Bruehlmeier, Matthias; Schubiger, P. August; Ametamey, Simon M. E-mail: simon-mensah.ametamey@psi.ch

    2002-01-01

    The compound 3{beta}-(4'-chlorophenyl)-2{beta}-(3'-phenylisoxazol-5'-yl)tropane (CPPIT or RTI 177) is a 2{beta}-heterocyclic substituted cocaine congener with high in vitro selectivity and affinity for the dopamine transporter relative to serotonin and norepinephrine transporters. The aim of the present study was to evaluate the in vivo selectivity of [{sup 11}C]-{beta}-CPPIT and to determine whether [{sup 11}C]-{beta}-CPPIT may be a suitable alternative to existing DAT PET radioligands. [{sup 11}C]-{beta}-CPPIT was prepared by N-alkylation of the free amine with [{sup 11}C]methyl iodide. In mouse brain, the striatal binding of [{sup 11}C]-{beta}-CPPIT was reduced significantly by preinjecting the dopamine reuptake antagonist GBR 12909 (5 mg/kg). By contrast, radioactivity uptake in the brain was not affected significantly by the preinjection of citalopram (5 mg/kg) and desipramine (5 mg/kg), inhibitors for the serotonin and norepinephrine transporters, respectively. No effect was also observed by pretreatment with ketanserin (2.5 mg/kg) a compound with high affinity for the 5-HT{sub 2A}-receptor and the vesicular monoamine transporter. In a PET study with six healthy volunteers high striatal uptake was observed. The distribution pattern of [{sup 11}C]-{beta}-CPPIT was similar to the known distribution of the dopamine transporter in the human brain. Compared to {sup 123}I labeled {beta}-CIT, the rate of metabolic degradation of [{sup 11}C]-{beta}-CPPIT was almost twofold slower suggesting that bioisosteric heterocyclic substitution of the ester group at the 2{beta}-position of the tropane ring does have an influence on the rate of metabolism of [{sup 11}C]-{beta}-CPPIT. The rank order of the distribution volumes obtained via the one-tissue compartment model is also similar to the reported distribution of DAT. These preliminary results suggest that [{sup 11}C]-{beta}-CPPIT may be a useful PET radioligand for the visualization and quantification of

  15. Saturated fat consumption and the Theory of Planned Behaviour: exploring additive and interactive effects of habit strength.

    Science.gov (United States)

    de Bruijn, Gert-Jan; Kroeze, Willemieke; Oenema, Anke; Brug, Johannes

    2008-09-01

    The additive and interactive effects of habit strength in the explanation of saturated fat intake were explored within the framework of the Theory of Planned Behaviour (TPB). Cross-sectional data were gathered in a Dutch adult sample (n=764) using self-administered questionnaires and analyzed using hierarchical regression analyses and simple slope analyses. Results showed that habit strength was a significant correlate of fat intake (beta=-0.11) and significantly increased the amount of explained variance in fat intake (R(2-change)=0.01). Furthermore, based on a significant interaction effect (beta=0.11), simple slope analyses revealed that intention was a significant correlate of fat intake for low levels (beta=-0.29) and medium levels (beta=-0.19) of habit strength, but a weaker and non-significant correlate for high levels (beta=-0.07) of habit strength. Higher habit strength may thus make limiting fat intake a non-intentional behaviour. Implications for information and motivation-based interventions are discussed. PMID:18471932

  16. Character strengths and virtues

    Directory of Open Access Journals (Sweden)

    Mariana Gancedo

    2015-09-01

    Full Text Available The target of this work is to carry out a critical analysis about some of the underlying epistemological assumptions in Peterson and Seligman’s book Character Strengths and Virtues. A handbook and classifications (2004. This is a theoretical investigation that belongs to the epistemology of psychology field. According to the theory proposed by Serroni Copello (2003, a critic progress rational criterion is methodologically applied. The analysis points out some epistemological weakness that leads to incongruences in the statements and conclusions of the investigations, such as: the absence of a unified theory, a candid search of objectivity, and the superposition of implicit paradigms. It also takes notice of a causal and elementary logic -which goes against today’s scientific paradigm-, and the strong American culture zeitgeist present in the principles of Positive Psychology. Finally, some ethic problems are displayed, in particular the step taken from a descriptive attitude –characteristic of science- toward a prescriptive attitude –characteristic of moral codes-. 

  17. The effect of elementary fibre variability on bamboo fibre strength

    International Nuclear Information System (INIS)

    Highlights: • Fibre diameter was found to have a significant effect on bamboo fibre strength. • The average fibre strength decreases with increasing quantity of elementary fibres. • A new model can be used for predicting fibre strength at different fibre diameters. - Abstract: Tensile strength of brittle fibres exhibits statistical distribution and size dependence. In this work, the average strength of bamboo fibre is found to decrease from 568 to 483 MPa as mean diameter increases from 196.6 to 584.3 μm. The morphologies of bamboo fibres with increasing diameters were investigated through Scanning Electron Microscopy (SEM) to demonstrate variations in the quantity of elementary fibres. The influence of elementary fibre distributions on the fibre strength was also studied. A modified Weibull model based on number of elementary fibres is proposed to perform scaling predictions for the fracture strength of the fibres at different between-fibre diameters. It was shown that the predicted results are in reasonable agreement with experimental data, highlighting the adequacies of the new analytical model for describing the diameter dependence of tensile strength

  18. Numerical calculation of relative dose rates from spherical 106Ru beta sources used in ophthalmic brachytherapy

    Directory of Open Access Journals (Sweden)

    Eduardo de Paiva

    2015-01-01

    Full Text Available Concave beta sources of 106Ru/106Rh are used in radiotherapy to treat ophthalmic tumors. However, a problem that arises is the difficult determination of absorbed dose distributions around such sources mainly because of the small range of the electrons and the steep dose gradients. In this sense, numerical methods have been developed to calculate the dose distributions around the beta applicators. In this work a simple code in Fortran language is developed to estimate the dose rates along the central axis of 106Ru/106Rh curved plaques by numerical integration of the beta point source function and results are compared with other calculated data.

  19. Numerical calculation of relative dose rates from spherical 106Ru beta sources used in ophthalmic brachytherapy

    Science.gov (United States)

    de Paiva, Eduardo

    Concave beta sources of 106Ru/106Rh are used in radiotherapy to treat ophthalmic tumors. However, a problem that arises is the difficult determination of absorbed dose distributions around such sources mainly because of the small range of the electrons and the steep dose gradients. In this sense, numerical methods have been developed to calculate the dose distributions around the beta applicators. In this work a simple code in Fortran language is developed to estimate the dose rates along the central axis of 106Ru/106Rh curved plaques by numerical integration of the beta point source function and results are compared with other calculated data.

  20. Vasodilatory mechanisms of beta receptor blockade.

    OpenAIRE

    Rath, Géraldine; Balligand, Jean-Luc; Dessy, Chantal

    2012-01-01

    Beta-blockers are widely prescribed for the treatment of a variety of cardiovascular pathologies. Compared to traditional beta-adrenergic antagonists, beta-blockers of the new generation exhibit ancillary properties such as vasodilation through different mechanisms. This translates into a more favorable hemodynamic profile. The relative affinities of beta-adrenoreceptor antagonists towards the three beta-adrenoreceptor isotypes matter for predicting their functional impact on vasomotor contro...

  1. Tables of double beta decay data

    Energy Technology Data Exchange (ETDEWEB)

    Tretyak, V.I. [AN Ukrainskoj SSR, Kiev (Ukraine)]|[Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; Zdesenko, Y.G. [AN Ukrainskoj SSR, Kiev (Ukraine)

    1995-12-31

    A compilation of experimental data on double beta decay is presented. The tables contain the most stringent known experimental limits or positive results of 2{beta} transitions of 69 natural nuclides to ground and excited states of daughter nuclei for different channels (2{beta}{sup -}; 2{beta}{sup +}; {epsilon}{beta}{sup +}; 2{epsilon}) and modes (0{nu}; 2{nu}; 0{nu}M) of decay. (authors). 189 refs., 9 figs., 3 tabs.

  2. THE EFFECT OF MOISTURE SORPTION ON THE STRENGTH AND INTERNAL SURFACE-AREA OF LACTOSE TABLETS

    NARCIS (Netherlands)

    RIEPMA, KA; DEKKER, BG; LERK, CF

    1992-01-01

    Tablets compacted from alpha-lactose monohydrate and from roller dried beta-lactose both show time-dependent moisture uptake when exposed to an ambient humid atmosphere. Moisture sorption tends to reach a plateau within 10 min and is accompanied by a decrease in both crushing strength and specific B

  3. Commitee III.1 Ultimate Strength

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher

    1997-01-01

    This report addresses the subject of ductile collapse of ships and offshore structures and their components due to buckling and excessive yielding under overload conditions. Consideration is given to load-deflection predictions for components with fabrication imperfections and in-service damage a...... to the ultimate strength and post-ultimate behaviour of structural systems in order to identify the reserve strength. The effect of uncertainties in the modelling on the strength predictions is highlighted in two design examples....

  4. Beta contamination monitor energy response

    International Nuclear Information System (INIS)

    Beta contamination is monitored at Los Alamos National Laboratory (LANL) with portable handheld probes and their associated counters, smear counters, air-breathing continuous air monitors (CAM), personnel contamination monitors (PCM), and hand and foot monitors (HFM). The response of these monitors was measured using a set of anodized-aluminum beta sources for the five isotopes: Carbon-14, Technetium-99, Cesium-137, Chlorine-36 and Strontium/Yttrium-90. The surface emission rates of the sources are traceable to the National Institute of Standards and Technology (NIST) with a precision of one relative standard deviation equal to 1.7%. All measurements were made in reproducible geometry, mostly using aluminum source holders. All counts, significantly above background, were collected to a precision of 1% or better. The study of the hand-held probes included measurements of six air gaps from 0.76 to 26.2 mm. The energy response of the detectors is well-parameterized as a function of the average beta energy of the isotopes (C14=50 keV, Tc99=85, Cs137=188, C136=246, and Sr/Y90=934). The authors conclude that Chlorine-36 is a suitable beta emitter for routine calibration. They recommend that a pancake Geiger-Mueller (GM) or gas-proportional counter be used for primarily beta contamination surveys with an air gap not to exceed 6 mm. Energy response varies about 30% from Tc99 to Sr/Y90 for the pancake GM detector. Dual alpha/beta probes have poor to negligible efficiency for low-energy betas. The rugged anodized sources represent partially imbedded contamination found in the field and they are provided with precise, NIST-traceable, emission rates for reliable calibration

  5. Beta beat correction and improvement in Indus-2 storage ring performance

    International Nuclear Information System (INIS)

    The periodicity restoration or the beta beat correction is an important step to enhance the operational performance of any storage ring in terms of the better injection efficiency and improved beam lifetime etc. A method of linear beam optics from closed orbit has been used for the beta beat correction in Indus-2 store ring, where 26 power supplies driving the 72 quadrupoles are used as a degree of freedoms. In this method, the measured response matrix is fitted to the theoretical orbit response matrix and deviations of the quadrupole strengths are determined. Correction of these deviation in strengths are applied in the operating machine through the power supplies driving the quadrupoles. We will discuss the method used for the beta beat correction in Indus-2 storage ring and will present the effects of the correction on the injection efficiency and beam lifetime. (author)

  6. Neutrinoless Double Beta Decay and High-Scale Baryogenesis

    CERN Document Server

    Graf, Lukas; Huang, Wei-Chih

    2015-01-01

    The constraints on baryogenesis models obtained from an observation of neutrinoless double beta decay are discussed. The lepton number violating processes, which can underlie neutrinoless double beta decay, would together with sphaleron processes, which are effective in a wide range of energies, wash out any primordial baryon asymmetry of the universe. Typically, if a mechanism of neutrinoless double beta decay other than the standard light neutrino exchange is observed, typical scenarios of high-scale baryogenesis will be excluded. This can be achieved by different methods, e.g. through the observation in multiple isotopes or the measurement of the decay distribution. In addition, we will also highlight the connection with low energy lepton flavour violation and lepton number violation at the LHC.

  7. Magnetic fields in beta Cep, SPB, and Be stars

    CERN Document Server

    Schoeller, M; Briquet, M; Ilyin, I

    2013-01-01

    Recent observational and theoretical results emphasize the potential significance of magnetic fields for structure, evolution, and environment of massive stars. Depending on their spectral and photometric behavior, the upper main-sequence B-type stars are assigned to different groups, such as beta Cep stars and slowly pulsating B (SPB) stars, He-rich and He-deficient Bp stars, Be stars, BpSi stars, HgMn stars, or normal B-type stars. All these groups are characterized by different magnetic field geometry and strength, from fields below the detection limit of a few Gauss up to tens of kG. Our collaboration was the first to systematically study the magnetic fields in representative samples of different types of main-sequence B stars. In this article, we give an overview about what we have learned during the last years about magnetic fields in beta Cep, SPB, and Be stars.

  8. ACCELERATORS: A GUI tool for beta function measurement using MATLAB

    Science.gov (United States)

    Chen, Guang-Ling; Tian, Shun-Qiang; Jiang, Bo-Cheng; Liu, Gui-Min

    2009-04-01

    The beta function measurement is used to detect the shift in the betatron tune as the strength of an individual quadrupole magnet is varied. A GUI (graphic user interface) tool for the beta function measurement is developed using the MATLAB program language in the Linux environment, which facilitates the commissioning of the Shanghai Synchrotron Radiation Facility (SSRF) storage ring. In this paper, we describe the design of the application and give some measuring results and discussions about the definition of the measurement. The program has been optimized to solve some restrictions of the AT tracking code. After the correction with LOCO (linear optics from closed orbits), the horizontal and the vertical root mean square values (rms values) can be reduced to 0.12 and 0.10.

  9. Beta titanium alloys and their role in the titanium industry

    Science.gov (United States)

    Bania, Paul J.

    1994-07-01

    The class of titanium alloys generically referred to as the beta alloys is arguably the most versatile in the titanium family. Since these alloys offer the highest strength-to-weight ratios and deepest hardenability of all titanium alloys, one might expect them to compete favorably for a variety of aerospace applications. To the contrary, however, except for one very successful application (Ti-13V-11Cr-3Al on the SR-71), the beta alloys have remained a very small segment of the industry. As a perspective on this situation, this article reviews some past and present applications of titanium alloys. It also descibes some unique new alloys and applications that promise to reverse historical trends.

  10. Grain boundary strength as point defect sink strength

    International Nuclear Information System (INIS)

    Sink strength of spherical grain boundary as an absolutely absorbing surface and as finite thickness wall consisting of the edge dislocations are considered. The values of the grain boundary sink strength are shown to be critically dependent on the point defect recombination degree

  11. Overview to Strength Development and Strength Trainings in Children

    Directory of Open Access Journals (Sweden)

    Mesut Hekim

    2015-08-01

    Full Text Available There are some important phases within psychomotor development process in children. Periods of movements related to sport appear in this phases. In this phase which contains 7-12 age period in children, a significant increment occurs in the physical and motoric development levels of children. Physical and motoric developments are supported by directing children in this age group to sport. In a plenty of studies, it was stated that participating to sports in children supports motoric features and physical development. Strength is one of the most important motoric features which develop via participating to sports. Children strength development is effected at positive direction by adaptation exercise made to support strength development. Psychomotor development basis are considered to obtain the best efficiency from workouts aimed strength development in children and to remove risks to be generate any injury/disability. In this research, strength development, contributions of participating in sports to strength development, strength training in children and children responses to strength training were all emphasized.

  12. Airborne field strength monitoring

    Directory of Open Access Journals (Sweden)

    J. Bredemeyer

    2007-06-01

    Full Text Available In civil and military aviation, ground based navigation aids (NAVAIDS are still crucial for flight guidance even though the acceptance of satellite based systems (GNSS increases. Part of the calibration process for NAVAIDS (ILS, DME, VOR is to perform a flight inspection according to specified methods as stated in a document (DOC8071, 2000 by the International Civil Aviation Organization (ICAO. One major task is to determine the coverage, or, in other words, the true signal-in-space field strength of a ground transmitter. This has always been a challenge to flight inspection up to now, since, especially in the L-band (DME, 1GHz, the antenna installed performance was known with an uncertainty of 10 dB or even more. In order to meet ICAO's required accuracy of ±3 dB it is necessary to have a precise 3-D antenna factor of the receiving antenna operating on the airborne platform including all losses and impedance mismatching. Introducing precise, effective antenna factors to flight inspection to achieve the required accuracy is new and not published in relevant papers yet. The authors try to establish a new balanced procedure between simulation and validation by airborne and ground measurements. This involves the interpretation of measured scattering parameters gained both on the ground and airborne in comparison with numerical results obtained by the multilevel fast multipole algorithm (MLFMA accelerated method of moments (MoM using a complex geometric model of the aircraft. First results will be presented in this paper.

  13. In-trap decay spectroscopy for {beta}{beta} decays

    Energy Technology Data Exchange (ETDEWEB)

    Brunner, Thomas

    2011-01-18

    The presented work describes the implementation of a new technique to measure electron-capture (EC) branching ratios (BRs) of intermediate nuclei in {beta}{beta} decays. This technique has been developed at TRIUMF in Vancouver, Canada. It facilitates one of TRIUMF's Ion Traps for Atomic and Nuclear science (TITAN), the Electron Beam Ion Trap (EBIT) that is used as a spectroscopy Penning trap. Radioactive ions, produced at the radioactive isotope facility ISAC, are injected and stored in the spectroscopy Penning trap while their decays are observed. A key feature of this technique is the use of a strong magnetic field, required for trapping. It radially confines electrons from {beta} decays along the trap axis while X-rays, following an EC, are emitted isotropically. This provides spatial separation of X-ray and {beta} detection with almost no {beta}-induced background at the X-ray detector, allowing weak EC branches to be measured. Furthermore, the combination of several traps allows one to isobarically clean the sample prior to the in-trap decay spectroscopy measurement. This technique has been developed to measure ECBRs of transition nuclei in {beta}{beta} decays. Detailed knowledge of these electron capture branches is crucial for a better understanding of the underlying nuclear physics in {beta}{beta} decays. These branches are typically of the order of 10{sup -5} and therefore difficult to measure. Conventional measurements suffer from isobaric contamination and a dominating {beta} background at theX-ray detector. Additionally, X-rays are attenuated by the material where the radioactive sample is implanted. To overcome these limitations, the technique of in-trap decay spectroscopy has been developed. In this work, the EBIT was connected to the TITAN beam line and has been commissioned. Using the developed beam diagnostics, ions were injected into the Penning trap and systematic studies on injection and storage optimization were performed. Furthermore, Ge

  14. Balance Discriminant and Development Design of Distribution Status on Competitive Strength of Summer Olympic Events%夏季奥运会设赛项目竞技实力国际分布状态平衡度判别及发展对策设计

    Institute of Scientific and Technical Information of China (English)

    陈丹

    2011-01-01

    The change process of Olympics event's international competitive strength is a trend from a balance to imbalance and even crisis,and to a balance again.The distribution status on competitive strength of Summer Olympics events is divided into the relativel%奥运会设赛项目竞技实力国际分布状态变化过程就是一个从均衡走向失衡甚至危机再到均衡的过程,三种状态交替出现符合事物发展的基本现象。采用三元等级判别法确定相对均衡态、失衡态和危机态三种分布状态的测度指标及其组合方式,完成对夏季奥运会31个设赛项目的竞技实力国际分布状态等级判定,期望为夏季奥运会设赛项目的平衡设置及世界、国家奥运项目部署提供切实可行的依据和对策。

  15. Cardiac glycoside-like structure and function of 5 beta,14 beta-pregnanes

    International Nuclear Information System (INIS)

    5 beta-Reduction and 14 beta-substitution convert the planar progesterone molecule to the cardiac glycoside configuration--A and D rings of the steroid moiety are bent toward the alpha-face relative to the B and C rings. Potency of the 5 beta,14 beta-derivative in a [3H]ouabain binding assay or its ability to inhibit the sodium pump in red blood cells is enhanced by 3 beta-hydroxylation, 20 beta-hydroxylation, and 3 beta-glycosidation. Synthesis of 14,20 beta-dihydroxy-3 beta-(beta-D-glucopyranosyloxy)- 5 beta,14 beta-pregnane from digitoxin is described. The glucoside is 1/20 as potent as ouabain and elicits prominent, sustained, positive inotropy in isolated cardiac muscle

  16. On some corrections to beta spectra measured by toroidal inron-free beta spectrometer

    International Nuclear Information System (INIS)

    In the investigations of the features of neutron-deficient isotopes to study low-intensity branches of positron decay ST-2 the iron-free beta spectrometer with toroidal magnetic field (light intensity approximately 20%, resolution ability approximately 1%) is used. The influence of the factors distorting β-spectra in case of the ST-2 spectrometer has been studied. In using the sources without the carriers the source thickness at Esub(β) > 100 keV doesn't distort the spectrum. The investigation of the dependence of 22Na positron counting at different energies on theckness of the substrate made it possible to determine the paremeters of backscattering. It was shown that the backgroud of the spectrometer in positron measuring regime at energies Esub(β) > 100 keV didn't depend on the energy. The measurements at the energies higher than maximum positron energy give directly the background value. According to experimental distribution of the lines of conversion electrons the analytical kind of response function of the spectrometer has been obtained. Spectral distribution of monochromatic electrons consists of the peak, described by Gauss distribution, and exponential ''tail'' in the direction of small energies. The investigations showed that with the help of the ST-2 beta spectrometer the decay positron btanches with the intensity up to 0.01% per decay may be determined with the accuracy 2-3 keV. There is principal possibility to study form factors of β-spectra

  17. Report on the U.S. Geological Survey's evaluation program for standard reference samples distributed in October 1993 : T-127 (trace constituents), M-128 (major constituents), N-40 (nutrients), N-41 (nutrients), P-21 (low ionic strength), Hg-17 (mercury), AMW-3 (acid mine water), and WW-1 (whole water)

    Science.gov (United States)

    Long, H.K.; Farrar, J.W.

    1994-01-01

    This report presents the results of the U.S. Geological Survey's analytical evaluation program for eight standard reference samples--T-127 (trace constituents), M-128 (major constituents), N-40 (nutrients), N-41 (nutrients), P-21 (low ionic strength), Hg-17 (mercury), AMW-3 (acid mine water), and WW-1 (whole water)--that were distributed in October 1993 to 158 laboratories registered in the U.S. Geological Survey sponsored interlaboratory testing program. Analytical data that were received from 145 of the laboratories were evaluated with respect to: overall laboratory performance and relative laboratory performance for each analyte in the eight reference samples. Results of these evaluations are presented in tabular form. Also presented are tables and graphs summarizing the analytical data provided by each laboratory for each analyte in the eight standard reference samples. The most probable value for each analyte was determined using nonparametric statistics.

  18. The relevance of dose for low-energy beta emitters

    International Nuclear Information System (INIS)

    Specific issues in risk assessment for low-energy beta emitters include specification of the radiation weighting factor, values of relative biological effectiveness for specific or accurate risk estimates, non-uniformities of dose within tissues and cells, and use of standard tissue weighting factors for non-uniform situations. Unusual features of low-energy beta emitters include: increased average ionisation density on subcellular (and cellular) scales; short ranges of the beta electrons; non-uniformity of the absorbed dose over subcellular, cellular, and tissue dimensions; reduced hit frequencies; nuclear transmutations; different chemical forms, influencing biokinetics and dose distributions; and large isotopic mass differences, particularly in the case of tritium and hydrogen. Many of these features are not included explicitly in conventional radiation protection dosimetry, although they may be partly included in experimental determinations of relative biological effectiveness. Theoretical and experimental studies have shown low-energy electrons to be particularly efficient in producing double-strand breaks in DNA, including complex double-strand breaks. Hence, on fundamental grounds, tritium beta particles should be expected to have greater biological effectiveness per unit absorbed dose than 60Co gamma-rays or orthovoltage x-rays. For practical purposes, and in view of the paucity of epidemiological estimates of risk from low-energy electrons, consideration should be given to applying a raised relative biological effectiveness, say of value 2, to all low-energy internal emitters, including beta particles and soft x-ray emissions.

  19. Estimating the magnetic field strength from magnetograms

    CERN Document Server

    Ramos, A Asensio; Sainz, R Manso

    2015-01-01

    A properly calibrated longitudinal magnetograph is an instrument that measures circular polarization and gives an estimation of the magnetic flux density in each observed resolution element. This usually constitutes a lower bound of the field strength in the resolution element, given that it can be made arbitrarily large as long as it occupies a proportionally smaller area of the resolution element and/or becomes more transversal to the observer and still produce the same magnetic signal. Yet, we know that arbitrarily stronger fields are less likely --hG fields are more probable than kG fields, with fields above several kG virtually absent-- and we may even have partial information about its angular distribution. Based on a set of sensible considerations, we derive simple formulae based on a Bayesian analysis to give an improved estimation of the magnetic field strength for magnetographs.

  20. Methodology to determine the efficiency of a beta emitter gases monitor; Metodologia para determinacao da eficiencia de um monitor de gases emissores de particulas beta

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Marcos Rodrigues de

    1995-07-01

    This work presents a methodology developed to determinate the efficiency of air monitors used to measure the concentration of beta emitters noble gases in nuclear power stations. Efficiency values, obtained by means of theoretical computation are compared with experimental values. The experimental part of the work was performed using three different point beta source, to simulate small amounts of gas uniformly distributed in small volume. The comparison shows that theoretical an experimental values agree within 4,2 % for {sup 90}Sr + {sup 90}Y, {sup 204}Tl and {sup 45}Ca beta sources. (author)

  1. Bone strength and material properties of the glenoid

    DEFF Research Database (Denmark)

    Frich, Lars Henrik; Jensen, N.C.; Odgaard, A.; Pedersen, C.M.; Sjøbjerg, J.O.; Dalstra, M.

    1997-01-01

    models were all based on assumptions that the material properties of the glenoid were similar to those of the tibial plateau. The osteopenetrometer was used to assess the topographic strength distribution at the glenoid. Strength at the proximal subchondral level of the glenoid averaged 66.9 MPa. Higher...... of the cortical bone to the total glenoid strength was assessed by compression tests of pristine and cancellous-free glenoid specimens. Strength decreased by an average of 31% after the cancellous bone was removed. The material properties of the glenoid cancellous bone were determined by axial......The quality of the glenoid bone is important to a successful total shoulder replacement. Finite element models have been used to model the response of the glenoid bone to an implanted prosthesis. Because very little is known about the bone strength and the material properties at the glenoid, these...

  2. Loading Conditions and Longitudinal Strength

    DEFF Research Database (Denmark)

    Sørensen, Herman

    1995-01-01

    Methods for the calculation of the lightweight of the ship.Loading conditions satisfying draught, trim and intact stability requirements and analysis of the corresponding stillwater longitudinal strength.......Methods for the calculation of the lightweight of the ship.Loading conditions satisfying draught, trim and intact stability requirements and analysis of the corresponding stillwater longitudinal strength....

  3. Ultimate Strength, Committee III.1

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup; Estefan, S.; Fasano, E.;

    2003-01-01

    Concern for the ductile of ships and offshore structures and their structural components under ultimate conditions. Attention shall be given to the influence of fabrication imperfections and inservice damage and degradation on reserve strength. Uncertainties in strength models for design shall be...

  4. Metabolic clearance rate and urinary clearance of purified beta-core

    International Nuclear Information System (INIS)

    We injected a highly purified preparation of the beta-core molecule, a fragment of hCG beta excreted in pregnancy urine, into five men and three women to determine its kinetic parameters, MCR, and urinary clearance. The beta-core molecule was distributed in an initial volume [1950 +/- 156 (mean +/- SEM) mL/m2 body surface area] approximately equal to the estimated plasma volume. Its disappearance was multiexponential on a semilogarithmic plot, with a rapid phase t1/2 of 3.5 +/- 0.7 min and a slow phase t1/2 of 22.4 +/- 4.2 min. The transit time (the mean time spent by a molecule of beta-core in transit) was 20.6 +/- 2.1 min. The MCR was 192.0 +/- 8.0 mL/min.m2 body surface area. About 5% of the injected dose of beta-core was excreted into the urine in the first 30 min after injection, and low levels of excretion persisted for up to 7 days. The urinary clearance rate of beta-core was 13.7 +/- 1.4 mL/min.m2, accounting for about 8% of the elimination of beta-core from the plasma. The beta-core immunoreactivity in serum and urine was characterized by gel filtration and three independent RIA systems to show that its properties were indistinguishable from those of the injected beta-core. Serum levels of beta-core in pregnant women were less than 0.2 ng/mL, while the amounts excreted in their urine were as much as 5 mg/day. Based on these clearance parameters of beta-core in normal subjects, less than 0.2% of the beta-core excreted in pregnancy urine is derived by urinary clearance of plasma beta-core. Therefore, more than 99% of the beta-core excreted in pregnancy urine is derived from beta-core in a compartment separate from plasma. In particular, these data indicate that there is relatively little placental secretion of beta-core into plasma and that placental secretion does not account for the vast majority of beta-core in pregnancy urine

  5. 50 years forward: beta cells.

    Science.gov (United States)

    Halban, Philippe A

    2015-08-01

    Our understanding of beta cell development and function has increased substantially these past 50 years but much remains to be learned before this knowledge can be put to clinical use. A comprehensive business plan will be necessary to develop a detailed molecular and functional blueprint of the beta cell in health and disease based on an integrated approach involving all necessary research disciplines. This blueprint will provide a platform for the development of novel therapeutic strategies for the treatment of both major forms of diabetes, foremost among them beta cell replacement therapy. This is one of a series of commentaries under the banner '50 years forward', giving personal opinions on future perspectives in diabetes, to celebrate the 50th anniversary of Diabetologia (1965-2015). PMID:25957776

  6. Predicting Neutrinoless Double Beta Decay

    CERN Document Server

    Hirsch, M; Valle, J W F; Moral, A V; Ma, Ernest

    2005-01-01

    We give predictions for the neutrinoless double beta decay rate in a simple variant of the A_4 family symmetry model. We show that there is a lower bound for the neutrinoless double beta decay amplitude even in the case of normal hierarchical neutrino masses, corresponding to an effective mass parameter |m_{ee}| >= 0.17 \\sqrt{\\Delta m^2_{ATM}}. This result holds both for the CP conserving and CP violating cases. In the latter case we show explicitly that the lower bound on |m_{ee}| is sensitive to the value of the Majorana phase. We conclude therefore that in our scheme, neutrinoless double beta decay may be accessible to the next generation of high sensitivity experiments.

  7. Muscle strength in myasthenia gravis

    DEFF Research Database (Denmark)

    Cejvanovic, S; Vissing, J

    2014-01-01

    related to disease duration or gender. The aim of this study was to quantify the strength of patients with MG and investigate whether it is related to disease duration. METHODS: Eight muscle groups were tested by manual muscle testing and with a hand-held dynamometer in 38 patients with generalized MG and...... 37 healthy age- and gender-matched controls. The disease duration was recorded and compared with strength measures. RESULTS: On average, muscle strength was decreased by 28% compared with controls (P<0.01). Repeated strength measures in individual patients did not differ, suggesting that the muscle...... force reported was not subject to fatigue, but reflected fixed weakness. The male patients showed a greater reduction in muscle force in all eight muscle groups than women with MG (60% vs 77% of normal, P<0.05). In both men and women with MG, strength in shoulder abductors was most affected (51% vs 62...

  8. Remolded Undrained Strength of Soils

    Institute of Scientific and Technical Information of China (English)

    HONG Zhen-shun(洪振舜); LIU Han-long(刘汉龙); NEGAMI Takehito

    2003-01-01

    Extensive data of undrained shear strength for various remolded soils are compiled to normalize the remolded undrained strength. Remolded soils have a wide spectrum of liquid limits ranging from 25% to 412%. It is found that the remolded undrained strength is a function of water content and liquid limit. Furthermore, a simple index designated as normalized water content w* is introduced for normalizing remolded undrained strength for various soils. The normalized water content w* is the ratio of water content to liquid limit. The relationship between the remolded undrained strength and the normalized water content can be expressed by a simple equation. The new simple equation is not only valuable theoretically for helping in assessing the in-situ mechanical behavior, but also useful to ocean engineering practice.

  9. Superfluid (quantum) turbulence and distributed chaos

    CERN Document Server

    Bershadskii, A

    2016-01-01

    Properties of distributed chaos in superfluid (quantum) turbulence have been studied using the data of recent direct numerical simulations (HVBK two-fluid model for He II, and a moving grid in the frames of Gross-Pitaevskii model of the Bose-Einstein condensates at low temperatures). It is found that for the viscous (normal) component of the velocity field in He II the viscosity dominates the distributed chaos with the stretched exponential spectrum $\\exp(-k/k_{\\beta})^{\\beta}$ and $\\beta = 2/3$. For the superfluid component the distributed chaos is dominated by the vorticity correlation integral with $\\beta =1/2$ (the soft spontaneous breaking of the space translational symmetry - homogeneity). For very low temperature the distributed chaos is tuned to the large-scale coherent motions: the viscous (normal) component is tuned to the fundamental mode, whereas the superfluid component is subharmonically tuned. For the Gross-Pitaevskii superfluid turbulence incompressible part of the energy spectrum (containing ...

  10. Spectra of fluorinated rare earth. beta. -diketonates with added ligands

    Energy Technology Data Exchange (ETDEWEB)

    Khomenko, V.S.; Lozinskij, M.O.; Fialkov, Yu.A.; Rasshinina, T.A.; Krasovskaya, L.I. (AN Belorusskoj SSR, Minsk. Inst. Fiziki; AN Ukrainskoj SSR, Kiev. Inst. Organicheskoj Khimii)

    1984-01-01

    Different-ligand rare earth complexes are synthesized. Fluorated ..beta..-diketones, triethylphosphine oxide and trifluoracetic acid are used as active ligands. Mass-spectra of low and high resolution are taken at the energy of ionizing electrons of 70 eV, as well as luminescence spectra of complexes. Fragmentation ways of complexes decomposition under electron shock are studied. A series of changing the bound strength of additional ligands with europium in mixed complexes is determined. It is shown that the introduction of additional ligands can purposefully change physical and chemical properties of complexes.

  11. Mechanism of inactivation of alanine racemase by beta, beta, beta-trifluoroalanine

    International Nuclear Information System (INIS)

    The alanine racemases are a group of PLP-dependent bacterial enzymes that catalyze the racemization of alanine, providing D-alanine for cell wall synthesis. Inactivation of the alanine racemases from the Gram-negative organism Salmonella typhimurium and Gram-positive organism Bacillus stearothermophilus with beta, beta, beta-trifluoroalanine has been studied. The inactivation occurs with the same rate constant as that for formation of a broad 460-490-nm chromophore. Loss of two fluoride ions per mole of inactivated enzyme and retention of [1-14C]trifluoroalanine label accompany inhibition, suggesting a monofluoro enzyme adduct. Partial denaturation (1 M guanidine) leads to rapid return of the initial 420-nm chromophore, followed by a slower (t1/2 approximately 30 min-1 h) loss of the fluoride ion and 14CO2 release. At this point, reduction by NaB3H4 and tryptic digestion yield a single radiolabeled peptide. Purification and sequencing of the peptide reveals that lysine-38 is covalently attached to the PLP cofactor. A mechanism for enzyme inactivation by trifluoroalanine is proposed and contrasted with earlier results on monohaloalanines, in which nucleophilic attack of released aminoacrylate on the PLP aldimine leads to enzyme inactivation. For trifluoroalanine inactivation, nucleophilic attack of lysine-38 on the electrophilic beta-difluoro-alpha, beta-unsaturated imine provides an alternative mode of inhibition for these enzymes

  12. Beta-ray dose assessment from skin contamination using a point kernel method

    International Nuclear Information System (INIS)

    In this study, a point kernel method to calculate beta-ray dose rate from skin contamination was introduced. The beta-ray doses rates were computed by performing numerical integration of the radial dose distribution around an isotropic point source of monoenergetic electrons called as point kernel. In this study, in-house code, based on MATLAB version 7.0.4 was developed to perform a numerical integration. The code generated dose distributions for beta-ray emitters from interpolated point kernel, and beta-ray dose rates from skin contamination were calculated by numerical integration. Generated dose distributions for selected beta-ray emitters agreed with those calculated by Cross et al within 20%, except at a longer distance where there are differences up to more than 100%. For a point source, calculated beta-ray doses were agreed well with those derived from Monte Carlo simulation. For a disk source, the differences were up to 17% at a deep region. Point kernel method underestimated beta-ray doses than Monte Carlo simulation. The code will be improved to deal with a three-dimensional source, shielding by cover material, air gap and contribution of photon to skin dose. For the sake of user's convenience, the code will be equipped with graphic user interface. (author)

  13. Beta-delayed gamma decay of 26P: Possible evidence of a proton halo

    CERN Document Server

    Pérez-Loureiro, D; Bennett, M B; Liddick, S N; Bowe, A; Brown, B A; Chen, A A; Chipps, K A; Cooper, N; Irvine, D; McNeice, E; Montes, F; Naqvi, F; Ortez, R; Pain, S D; Pereira, J; Prokop, C J; Quaglia, J; Quinn, S J; Sakstrup, J; Santia, M; Schwartz, S B; Shanab, S; Simon, A; Spyrou, A; Thiagalingam, E

    2016-01-01

    Background: Measurements of $\\beta$ decay provide important nuclear structure information that can be used to probe isospin asymmetries and inform nuclear astrophysics studies. Purpose: To measure the $\\beta$-delayed $\\gamma$ decay of $^{26}$P and compare the results with previous experimental results and shell-model calculations. Method: A $^{26}$P fast beam produced using nuclear fragmentation was implanted into a planar germanium detector. Its $\\beta$-delayed $\\gamma$-ray emission was measured with an array of 16 high-purity germanium detectors. Positrons emitted in the decay were detected in coincidence to reduce the background. Results: The absolute intensities of $^{26}$P $\\beta$-delayed $\\gamma$-rays were determined. A total of six new $\\beta$-decay branches and 15 new $\\gamma$-ray lines have been observed for the first time in $^{26}$P $\\beta$-decay. A complete $\\beta$-decay scheme was built for the allowed transitions to bound excited states of $^{26}$Si. $ft$ values and Gamow-Teller strengths were a...

  14. Buoyancy driven turbulence and distributed chaos

    CERN Document Server

    Bershadskii, A

    2016-01-01

    It is shown, using results of recent direct numerical simulations, laboratory experiments and atmospheric measurements, that buoyancy driven turbulence exhibits a broad diversity of the types of distributed chaos with its stretched exponential spectrum $\\exp(-k/k_{\\beta})^{\\beta}$. The distributed chaos with $\\beta = 1/3$ (determined by the helicity correlation integral) is the most common feature of the stably stratified turbulence (due to the strong helical waves presence). These waves mostly dominate spectral properties of the vertical component of velocity field, while the horizontal component is dominated by the diffusive processes both for the weak and strong stable stratification ($\\beta =2/3$). For the last case influence of the low boundary can overcome the wave effects and result in $\\beta =1/2$ for the vertical component of the velocity field (the spontaneous breaking of the space translational symmetry - homogeneity). For the unstably stratified turbulence in the Rayleigh-Taylor mixing zone the di...

  15. G×E Interaction Influences Trajectories of Hand Grip Strength

    DEFF Research Database (Denmark)

    Petersen, Inge; Pedersen, Nancy L; Rantanen, Taina;

    2016-01-01

    Age-related decline in grip strength predicts later life disability, frailty, lower well-being and cognitive change. While grip strength is heritable, genetic influence on change in grip strength has been relatively ignored, with non-shared environmental influence identified as the primary...... Environment across Multiple Studies consortium. Growth curve parameters were estimated for same-sex pairs, aged 34-99 (N = 10,681). Fisher's test for mixture distribution of within-monozygotic twin-pair differences (N = 1724) was performed on growth curve parameters. We observed significant gene...

  16. Evaluation of statistical strength of bamboo fiber and mechanical properties of fiber reinforced green composites

    Institute of Scientific and Technical Information of China (English)

    曹勇; 吴义强

    2008-01-01

    Green composites made from bamboo fibers and biodegradable resins were fabricated with press molding.On the basis of the Weibull distribution and the weakest-link theory,the statistical strength and distribution of bamboo fiber were analyzed,and the tensile strength of green composites was also investigated.The result confirms that the tensile statistical strength of fiber fits well with two-parameter Weibull distribution.In addition,the tensile strength of bamboo fiber reinforced composites is about 330 MPa with the fiber volume fraction of 70%.This value is close to or higher than that of other natural fiber reinforced green composites.

  17. Generalized Parton Distributions and their Singularities

    Energy Technology Data Exchange (ETDEWEB)

    Anatoly Radyushkin

    2011-04-01

    A new approach to building models of generalized parton distributions (GPDs) is discussed that is based on the factorized DD (double distribution) Ansatz within the single-DD formalism. The latter was not used before, because reconstructing GPDs from the forward limit one should start in this case with a very singular function $f(\\beta)/\\beta$ rather than with the usual parton density $f(\\beta)$. This results in a non-integrable singularity at $\\beta=0$ exaggerated by the fact that $f(\\beta)$'s, on their own, have a singular $\\beta^{-a}$ Regge behavior for small $\\beta$. It is shown that the singularity is regulated within the GPD model of Szczepaniak et al., in which the Regge behavior is implanted through a subtracted dispersion relation for the hadron-parton scattering amplitude. It is demonstrated that using proper softening of the quark-hadron vertices in the regions of large parton virtualities results in model GPDs $H(x,\\xi)$ that are finite and continuous at the "border point'' $x=\\xi$. Using a simple input forward distribution, we illustrate the implementation of the new approach for explicit construction of model GPDs. As a further development, a more general method of regulating the $\\beta=0$ singularities is proposed that is based on the separation of the initial single DD $f(\\beta, \\alpha)$ into the "plus'' part $[f(\\beta,\\alpha)]_{+}$ and the $D$-term. It is demonstrated that the "DD+D'' separation method allows to (re)derive GPD sum rules that relate the difference between the forward distribution $f(x)=H(x,0)$ and the border function $H(x,x)$ with the $D$-term function $D(\\alpha)$.

  18. Constraining neutrinoless double beta decay

    International Nuclear Information System (INIS)

    A class of discrete flavor-symmetry-based models predicts constrained neutrino mass matrix schemes that lead to specific neutrino mass sum-rules (MSR). We show how these theories may constrain the absolute scale of neutrino mass, leading in most of the cases to a lower bound on the neutrinoless double beta decay effective amplitude.

  19. *608440 LACTAMASE, BETA; LACTB [OMIM

    Lifescience Database Archive (English)

    Full Text Available FIELD NO 608440 FIELD TI 608440 LACTAMASE, BETA; LACTB ;;MITOCHONDRIAL RIBOSOMAL PROTEIN L56; MR ... Chen et al. (2008) recorded weight, fat mass, and lean ... mass for Lpl heterozygous null mice, Lactb transge ... ifferent from those of controls, with the fat mass/lean ... mass ratio difference generally increasing over ti ...

  20. Nuclear $\\beta^+$/EC decays in covariant density functional theory and the impact of isoscalar proton-neutron pairing

    CERN Document Server

    Niu, Z M; Liu, Q; Liang, H Z; Guo, J Y

    2013-01-01

    Self-consistent proton-neutron quasiparticle random phase approximation based on the spherical nonlinear point-coupling relativistic Hartree-Bogoliubov theory is established and used to investigate the $\\beta^+$/EC-decay half-lives of neutron-deficient Ar, Ca, Ti, Fe, Ni, Zn, Cd, and Sn isotopes. The isoscalar proton-neutron pairing is found to play an important role in reducing the decay half-lives, which is consistent with the same mechanism in the $\\beta$ decays of neutron-rich nuclei. The experimental $\\beta^+$/EC-decay half-lives can be well reproduced by a universal isoscalar proton-neutron pairing strength.

  1. The Strength of Rubble Pile Asteroids

    Science.gov (United States)

    Scheeres, D. J.; Sanchez, P.

    2012-12-01

    The rubble pile hypothesis for small asteroids in the Near Earth and Main Belt populations have been driven by several factors, including the observed high porosity of those bodies whose mass have been measured, the evident limitation on spin rate of asteroids larger than ~500 meters, and direct observation of the surface morphology of these bodies. Given these observations, it has been presumed that small asteroids should evolve as if they were cohesionless collections of grains. Detailed geophysical analysis of these bodies by Holsapple (Icarus 2010) show that cohesionless bodies will evolve under the addition of angular momentum by the YORP effect into more distended and, paradoxically, more slowly rotating bodies. Additional analysis in Holsapple (Icarus 2007) has shown that cohesional strength within a rubble pile could strengthen a collection of grains to the point where they could sustain rapid rotation. In our current talk we use the above as a starting point and incorporate new observations of the asteroid morphology driven by recent analysis of asteroid Itokawa by the Hayabusa science team and research on the mechanics of grains in the space environment (Scheeres et al. 2010). Analysis of images of Itokawa determined a measured size distribution of 1/d^3 for larger grains on asteroid Itokawa (Michikami et al., Earth Planets Space, 60, 13-20, 2008). Analysis of the sample shows the presence of micron sized dust on that asteroid's surface (Tsuchiyama et al., Science 333, 1125, 2011). Combining these observations provides a global indication of grain distribution within rubble piles. Even assuming a less steep distribution of 1/d^2 for dust grains smaller than 1 mm in size, the interior of Itokawa should still be dominated by the finest dust grains, with the mean grain size equal to ~ twice the smallest grain in the distribution. One implication of this result is that fines are present on the surface of the rubble pile Itokawa and thus should be distributed

  2. Monitor for alpha beta contamination of hands

    International Nuclear Information System (INIS)

    The following specifications of hands alpha beta contamination monitor are presented: the position of the hands, the detection and separation of alpha and beta, the information processing, the programming, the results presentation and general characteristics. (A.L.B.)

  3. How Do Beta Blocker Drugs Affect Exercise?

    Science.gov (United States)

    ... Stroke More How do beta blocker drugs affect exercise? Updated:Aug 5,2015 Beta blockers are a ... about them: Do they affect your ability to exercise? The answer can vary a great deal, depending ...

  4. Interferon Beta-1a Intramuscular Injection

    Science.gov (United States)

    Interferon beta-1a intramuscular injection is used to reduce the number of episodes of symptoms and slow ... and problems with vision, speech, and bladder control). Interferon beta-1a is in a class of medications ...

  5. Interferon Beta-1a Subcutaneous Injection

    Science.gov (United States)

    Interferon beta-1a subcutaneous injection is used to reduce episodes of symptoms and slow the development of ... and problems with vision, speech, and bladder control). Interferon beta-1a is in a class of medications ...

  6. The beta subunit of casein kinase II

    DEFF Research Database (Denmark)

    Boldyreff, B; Piontek, K; Schmidt-Spaniol, I; Issinger, O G

    1991-01-01

    cDNAs encoding the beta subunit of pig and mouse CKII were isolated. The porcine cDNA was expressed as a fusion protein in Escherichia coli and used for the production of anti-CKII-beta subunit specific antibodies.......cDNAs encoding the beta subunit of pig and mouse CKII were isolated. The porcine cDNA was expressed as a fusion protein in Escherichia coli and used for the production of anti-CKII-beta subunit specific antibodies....

  7. Beta adrenergic receptors in pigmented ciliary processes.

    OpenAIRE

    Trope, G. E.; Clark, B.

    1982-01-01

    Beta adrenergic receptors from membrane fragments of pigmented sheep eyes were studied and characterised by ligand binding techniques after the removal of melanin. In a representative experiment the beta max (total number of beta receptors) was 394.9 fmol/mg protein. The receptor affinity (Ka) was 440 pM. The potency series of drugs to displace 125I-HYP from the receptors was timolol = (-) propranolol greater than (+) propranolol greater than salbutamol greater than practolol. beta 1 Recepto...

  8. Pygmy dipole strength in 90Zr

    CERN Document Server

    Schwengner, R; Tsoneva, N; Benouaret, N; Beyer, R; Erhard, M; Grosse, E; Junghans, A R; Klug, J; Kosev, K; Lenske, H; Nair, C; Schilling, K D; Wagner, A

    2008-01-01

    The dipole response of the N=50 nucleus 90Zr was studied in photon-scattering experiments at the electron linear accelerator ELBE with bremsstrahlung produced at kinetic electron energies of 7.9, 9.0, and 13.2 MeV. We identified 189 levels up to an excitation energy of 12.9 MeV. Statistical methods were applied to estimate intensities of inelastic transitions and to correct the intensities of the ground-state transitions for their branching ratios. In this way we derived the photoabsorption cross section up to the neutron-separation energy. This cross section matches well the photoabsorption cross section obtained from (gamma,n) data and thus provides information about the extension of the dipole-strength distribution toward energies below the neutron-separation energy. An enhancement of E1 strength has been found in the range of 6 MeV to 11 MeV. Calculations within the framework of the quasiparticle-phonon model ascribe this strength to a vibration of the excessive neutrons against the N = Z neutron-proton c...

  9. Buoyancy storms in a zonal stream on the polar beta-plane: experiments with altimetry

    CERN Document Server

    Sui, Yi

    2013-01-01

    Results from a new series of experiments on flows generated by localized heating in the presence of a background zonal current on the polar beta-plane are presented. The flow induced by a heater without the background zonal flow is in the form of a beta-plume. Zonal jets of alternating directions are formed within the plume. The westward transport velocity in the plume is proportional to the upwelling velocity above the heater in agreement with linear theory. When the background flow in the form of the eastward zonal current is present, the beta-plume can be overwhelmed by the eastward current. The main control parameters of the experiment are the strength of the heater and strength of the sink which is used to create the background flow. The regime diagram shows the area where a beta-plume can exist in the parameter space. The critical value of the velocity of the zonal flow below which the beta-plume can exist is obtained by considering barotropic Rossby waves emitted by the baroclinic eddies in the heated ...

  10. Theory of high-beta tokamaks

    International Nuclear Information System (INIS)

    The theoretical researches on high beta tokamak are reviewed. The ballooning mode instability is thought to be the most serious problem for the high beta tokamaks, and the theoretical results on the ballooning mode instability are discussed in detail. The experimental results in high beta belt pinch devices are also discussed. (author)

  11. Interferon Beta-1a Intramuscular Injection

    Science.gov (United States)

    Interferon beta-1a intramuscular injection is used to reduce the number of episodes of symptoms and slow the development of disability in patients ... Interferon beta-1a intramuscular injection comes as a powder in vials to be mixed into a solution for injection. Interferon beta-1a intramuscular ...

  12. Beta measurements at Department of Energy facilities

    International Nuclear Information System (INIS)

    Pacific Northwest Laboratory performed a two-step process to characterize the current beta measurement practices at DOE facilities. PNL issued a survey questionnaire on beta measurement practices to DOE facilities and reported the results. PNL measured beta doses and spectra at seven selected DOE facilities and compared selected measurement techniques in the facility environment. This report documents the results of the radiation field measurements and the comparison of measurement techniques at the seven facilities. Data collected included beta dose and spectral measurements at seven DOE facilities that had high beta-to-gamma ratios (using a silicon surface barrier spectrometer, a plastic scintillator spectrometer, and a multielement beta dosimeter). Other dosimeters and survey meters representative of those used at DOE facilities or under development were also used for comparison. Field spectra were obtained under two distinct conditions. Silicon- and scintillation-based spectrometer systems were used under laboratory conditions where high beta-to-gamma dose ratios made the beta spectra easier to observe and analyze. In the second case, beta spectrometers were taken into actual production and maintenance areas of DOE facilities. Analyses of beta and gamma spectra showed that 234Th- /sup 234m/Pa, 231Th, 137Cs, and 90Sr/90Y were the major nuclides contributing to beta doses at the facilities visited. Beta doses from other fission products and 60Co were also measured, but the potential for exposure was less significant. 21 refs., 64 figs., 18 tabs

  13. Strength Degradation of Gfrp Bars

    OpenAIRE

    Bhise, Vikrant Sudhakar

    2002-01-01

    The primary objective of this research was to examine the strength degradation of Glass Fiber Reinforced Polymer (GFRP) bars at high temperature and alkalinity and determine if an Arrhenius type relationship can be used as a means of projecting life. The work done includes a thorough literature review, experiments and development of strength prediction models. The experimental work involves exposure of GFRP bars incased in cement mortar to lime-water solution at 30, 45 and 57°C. Overall 100 ...

  14. Impact strength of reactor graphite

    International Nuclear Information System (INIS)

    Dose dependences of impact strength of reactor graphite irradiated with neutrons at 340-360, 420-460 and 620-800 K by the fluence of up to 1.3x1022 cm-2 are plotted. It is pointed out that for the temperature range and fluence studied impact strength, as well as crack resistance, of reactor graphite exceed the same parameters of graphite before irradiation

  15. Combinatorial clustering and the beta negative binomial process

    OpenAIRE

    Broderick, Tamara; Mackey, Lester; Paisley, John; Jordan, Michael I

    2011-01-01

    We develop a Bayesian nonparametric approach to a general family of latent class problems in which individuals can belong simultaneously to multiple classes and where each class can be exhibited multiple times by an individual. We introduce a combinatorial stochastic process known as the negative binomial process (NBP) as an infinite-dimensional prior appropriate for such problems. We show that the NBP is conjugate to the beta process, and we characterize the posterior distribution under the ...

  16. Beta-adrenergic agonists as additive in beef cattle

    OpenAIRE

    Marcelo Vedovatto; Camila Celeste Brandão Ferreira Ítavo; João Artêmio Marin Beltrame; Ricardo Carneiro Brumatti; Gumercindo Loriano Franco

    2014-01-01

    The agonists receptor beta-adrenergic (β-AA) are present in virtually all types of mammalian cells and are stimulated by catecholamines (epinephrine and norepinephrine) produced by the organism itself. The β-AA agonists are synthetic substances with similar structure to these amines. When provided in the diet they alter the body composition of animals, affecting the distribution of nutrients toward to protein deposition, and decreasing lipogenesis. Although the mechanisms of action are not fu...

  17. Characteristics of structural loess strength and preliminary framework for joint strength formula

    OpenAIRE

    Rong-jian LI; Jun-ding LIU; Yan, Rui; Zheng, Wen; Sheng-jun SHAO

    2014-01-01

    The strength of structural loess consists of the shear strength and tensile strength. In this study, the stress path, the failure envelope of principal stress ( line), and the strength failure envelope of structurally intact loess and remolded loess were analyzed through three kinds of tests: the tensile strength test, the uniaxial compressive strength test, and the conventional triaxial shear strength test. Then, in order to describe the tensile strength and shear strength of structural loes...

  18. Ex vivo evaluation of N-(3-[{sup 18}F]fluoropropyl)-2{beta}-carbomethoxy-3{beta}-(4-fluorophenyl)nortrop ane in rats

    Energy Technology Data Exchange (ETDEWEB)

    Koivula, Teija [Laboratory of Radiochemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki (Finland); Marjamaeki, Paeivi; Haaparanta, Merja; Fagerholm, Veronica; Groenroos, Tove [MediCity PET Laboratory, Turku PET Centre, Tykistoekatu 6 A, FI-20520 Turku (Finland); Lipponen, Tiina; Perhola, Outi [Laboratory of Radiochemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki (Finland); Vepsaelaeinen, Jouko [Department of Chemistry, University of Kuopio, P.O. Box 1627, FI-70210 Kuopio (Finland); Solin, Olof [Laboratory of Radiochemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki (Finland); MediCity PET Laboratory, Turku PET Centre, Tykistoekatu 6 A, FI-20520 Turku (Finland)], E-mail: olof.solin@abo.fi

    2008-02-15

    Introduction: The dopamine transporter (DAT) ligand N-(3-fluoropropyl)-2{beta}-carbomethoxy-3{beta}-(4-fluorophenyl)nortropane ({beta}-CFT-FP) was labeled with fluorine-18, and its biodistribution was evaluated in rats ex vivo. Methods: The distribution of {sup 18}F radioactivity in the brain and peripheral organs and tissues was determined at several time points 5-120 min after intravenous injection of [{sup 18}F]{beta}-CFT-FP. Results: The highest brain uptake of [{sup 18}F]{beta}-CFT-FP was localized in the striatum; limbic structures also exhibited high uptake. Low uptake was found in the cerebellum. The highest ratio of striatum-to-cerebellum uptake, already reached within 5 min, was 3.1. Pretreatment with the selective DAT inhibitor GBR12909 significantly decreased [{sup 18}F]{beta}-CFT-FP uptake in the striatum. In most peripheral tissues, the highest uptake was found at 5 min, indicating fast washout of the radioligand. Some accumulation of {sup 18}F radioactivity was seen in bone as a function of time, reflecting defluorination of the radioligand. Conclusion: The results indicate that [{sup 18}F]{beta}-CFT-FP is a potential radioligand for studying DAT in vivo with positron emission tomography.

  19. Shear adhesion strength of aligned electrospun nanofibers.

    Science.gov (United States)

    Najem, Johnny F; Wong, Shing-Chung; Ji, Guang

    2014-09-01

    Inspiration from nature such as insects' foot hairs motivates scientists to fabricate nanoscale cylindrical solids that allow tens of millions of contact points per unit area with material substrates. In this paper, we present a simple yet robust method for fabricating directionally sensitive shear adhesive laminates. By using aligned electrospun nylon-6, we create dry adhesives, as a succession of our previous work on measuring adhesion energies between two single free-standing electrospun polymer fibers in cross-cylinder geometry, randomly oriented membranes and substrate, and peel forces between aligned fibers and substrate. The synthetic aligned cylindrical solids in this study are electrically insulating and show a maximal Mode II shear adhesion strength of 27 N/cm(2) on a glass slide. This measured value, for the purpose of comparison, is 270% of that reported from gecko feet. The Mode II shear adhesion strength, based on a commonly known "dead-weight" test, is 97-fold greater than the Mode I (normal) adhesion strength of the same. The data indicate a strong shear binding on and easy normal lifting off. Anisotropic adhesion (Mode II/Mode I) is pronounced. The size and surface boundary effects, crystallinity, and bending stiffness of fibers are used to understand these electrospun nanofibers, which vastly differ from otherwise known adhesive technologies. The anisotropic strength distribution is attributed to a decreasing fiber diameter and an optimized laminate thickness, which, in turn, influences the bending stiffness and solid-state "wettability" of points of contact between nanofibers and surface asperities. PMID:25105533

  20. Methodology to determine the efficiency of a beta emitter gases monitor

    International Nuclear Information System (INIS)

    This work presents a methodology developed to determinate the efficiency of air monitors used to measure the concentration of beta emitters noble gases in nuclear power stations. Efficiency values, obtained by means of theoretical computation are compared with experimental values. The experimental part of the work was performed using three different point beta source, to simulate small amounts of gas uniformly distributed in small volume. The comparison shows that theoretical an experimental values agree within 4,2 % for 90Sr + 90Y, 204Tl and 45Ca beta sources. (author)

  1. Myocardial uptake of radioiodinated fatty acids under influence of beta-adrenoceptor antagonists in the dog

    International Nuclear Information System (INIS)

    The metabolic effects of Pindolol and Metoprolol on myocardial uptake and distribution of radioiodinated free fatty acids (131I-heptadecanoic acid) in the normal and acutely ischemic dog heart, are investigated. The study shows a decrease in uptake of 131I-heptadecanoic acid in the myocardium after administration of beta-blocking agents, which could have major implications: 1) for the administration of beta-blocking agents in the acute stage of myocardial infarction in clinical practice and 2) for the use of 131I-heptadecanoic acid as cardiac imaging agent in patients with or suspect for coronary artery disease whom are on beta-blocker therapy

  2. Fluctuation properties of strength function phenomena: A model study

    International Nuclear Information System (INIS)

    We study fluctuation properties of strength function phenomena by employing a quantum mechanical model where a single parent state couples with a large number of background states. The background system is devised in such a way that the classical dynamics of the system may show a regular, an irregular, or a chaotic character as a function of a single parameter. The coupling of the parent state to the background states produces a fragmentation of the parent state, giving rise to a strength function phenomenon. We study various measures of the strength function that characterize its bulk structure or fluctuation properties. They include energy moments, strength distribution, fractal dimensions of the strength function, and Fourier transform of the autocorrelation function. Some of these measures, such as strength distribution or Fourier transform of the autocorrelation function, reflect characteristic aspects of the dynamics of the background system, i.e., if they have a regular or a chaotic character, while measures such as energy moments or fractal dimensions are rather insensitive to the dynamics. copyright 1997 The American Physical Society

  3. Weibull Probability Model for Fracture Strength of Aluminium (1101)-Alumina Particle Reinforced Metal Matrix Composite

    Institute of Scientific and Technical Information of China (English)

    A.Suresh Babu; V.Jayabalan

    2009-01-01

    In recent times, conventional materials are replaced by metal matrix composites (MMCs) due to their high specific strength and modulus.Strength reliability, one of the key factors restricting wider use of composite materials in various applications, is commonly characterized by Weibull strength distribution function.In the present work, statistical analysis of the strength data of 15% volume alumina particle (mean size 15 μm)reinforced in aluminum alloy (1101 grade alloy) fabricated by stir casting method was carried out using Weibull probability model.Twelve tension tests were performed according to ASTM B577 standards and the test data, the corresponding Weibull distribution was obtained.Finally the reliability of the composite behavior in terms of its fracture strength was presented to ensure the reliability of composites for suitable applications.An important implication of the present study is that the Weibull distribution describes the experimentally measured strength data more appropriately.

  4. Beta thalassaemia mutations in Turkish Cypriots.

    OpenAIRE

    Sozuoz, A; Berkalp, A; A. Figus; Loi, A; Pirastu, M.; Cao, A

    1988-01-01

    Using oligonucleotide hybridisation or restriction endonuclease analysis, we have characterised the molecular defect in 94 patients with thalassaemia major and four with thalassaemia intermedia of Turkish Cypriot descent. We found that four mutations, namely beta+ IVS-1 nt 110, beta zero IVS-1 nt, beta+ IVS-1 nt 6, and beta+ IVS-2 nt 745 were prevalent, accounting for 69.9%, 11.7%, 8.7%, and 5.6% respectively of the beta thalassaemia chromosomes. This information may help in the organisation ...

  5. Fouling of Heat Transfer Surfaces Related to beta-Lactoglobulin Denaturation During Heat Processing of Milk.

    Science.gov (United States)

    Lalande, M; Tissier, J P

    1985-06-01

    Denaturation of beta-lactoglobulin during heating of milk in a plate heat exchanger has been investigated as an important factor in fouling the heat transfer surface. Using, on one hand, data on chemical composition of deposits obtained from biochemical analysis technics and, on the other hand, kinetic data of beta-Iactoglobulin denaturation, the distribution profile of deposits along the surface and the experimental fouling curves can be adequately predicted. PMID:20568150

  6. Symmetric Key Structural Residues in Symmetric Proteins with Beta-Trefoil Fold

    OpenAIRE

    Feng, Jianhui; Li, Mingfeng; Huang, Yanzhao; Xiao, Yi

    2010-01-01

    To understand how symmetric structures of many proteins are formed from asymmetric sequences, the proteins with two repeated beta-trefoil domains in Plant Cytotoxin B-chain family and all presently known beta-trefoil proteins are analyzed by structure-based multi-sequence alignments. The results show that all these proteins have similar key structural residues that are distributed symmetrically in their structures. These symmetric key structural residues are further analyzed in terms of inter...

  7. Probing New Physics Models of Neutrinoless Double Beta Decay with SuperNEMO

    CERN Document Server

    Arnold, R; Baker, J; Barabash, A S; Basharina-Freshville, A; Bongrand, M; Brudanin, V; Caffrey, A J; Cebrián, S; Chapon, A; Chauveau, E; Dafni, Th; Deppisch, F F; Diaz, J; Durand, D; Egorov, V; Evans, J J; Flack, R; Fushima, K-I; Irastorza, I García; Garrido, X; Gómez, H; Guillon, B; Holin, A; Holy, K; Horkey, J J; Hubert, Ph; Hugon, C; Iguaz, F J; Ishihara, N; Jackson, C M; Jullian, S; Kauer, M; Kochetov, O; Konovalov, S I; Kovalenko, V; Lamhamdi, T; Lang, K; Lutter, G; Luzón, G; Mamedov, F; Marquet, Ch; Mauger, F; Monrabal, F; Nachab, A; Nasteva, I; Nemchenok, I; Nguyen, C H; Nomachi, M; Nova, F; Ohsumi, H; Pahlka, R B; Perrot, F; Piquemal, F; Povinec, P P; Richards, B; Ricol, J S; Riddle, C L; Rodríguez, A; Saakyan, R; Sarazin, X; Sedgbeer, J K; Serra, L; Shitov, Yu; Simard, L; Šimkovic, F; Söldner-Rembold, S; Štekl, I; Sutton, C S; Tamagawa, Y; Thomas, J; Timkin, V; Tretyak, V; Tretyak, Vl I; Umatov, V I; Vanyushin, I A; Vasiliev, R; Vasiliev, V; Vorobel, V; Waters, D; Yahlali, N; Žukauskas, A

    2010-01-01

    The possibility to probe new physics scenarios of light Majorana neutrino exchange and right-handed currents at the planned next generation neutrinoless double beta decay experiment SuperNEMO is discussed. Its ability to study different isotopes and track the outgoing electrons provides the means to discriminate different underlying mechanisms for the neutrinoless double beta decay by measuring the decay half-life and the electron angular and energy distributions.

  8. A note on the estimation of asset pricing models using simple regression betas

    OpenAIRE

    Kan, Raymond; Robotti, Cesare

    2009-01-01

    Since Black, Jensen, and Scholes (1972) and Fama and MacBeth (1973), the two-pass cross-sectional regression (CSR) methodology has become the most popular tool for estimating and testing beta asset pricing models. In this paper, we focus on the case in which simple regression betas are used as regressors in the second-pass CSR. Under general distributional assumptions, we derive asymptotic standard errors of the risk premia estimates that are robust to model misspecification. When testing whe...

  9. Beta-Negative Binomial Process and Exchangeable Random Partitions for Mixed-Membership Modeling

    OpenAIRE

    Zhou, Mingyuan

    2014-01-01

    The beta-negative binomial process (BNBP), an integer-valued stochastic process, is employed to partition a count vector into a latent random count matrix. As the marginal probability distribution of the BNBP that governs the exchangeable random partitions of grouped data has not yet been developed, current inference for the BNBP has to truncate the number of atoms of the beta process. This paper introduces an exchangeable partition probability function to explicitly describe how the BNBP clu...

  10. Colloidal gold immunolabeling of immunoglobulin-binding sites and beta antigen in group B streptococci.

    OpenAIRE

    Coleman, S E; Brady, L. J.; Boyle, M D

    1990-01-01

    We have characterized the immunoglobulin A (IgA)-Fc-binding properties and beta-antigen expression of several strains of group B streptococci by using ultrastructural immunocytochemistry. Colloidal gold-labeled tracers were used with intact and sectioned bacteria in order to gain information regarding the location and distribution of cell surface and cytoplasmic IgA-Fc-binding molecules and beta antigen. Colloidal gold (5- or 15-nm particles) was conjugated to IgA to characterize IgA-binding ...

  11. CRFR1 is expressed on pancreatic beta cells, promotes beta cell proliferation, and potentiates insulin secretion in a glucose-dependent manner

    DEFF Research Database (Denmark)

    Huising, Mark O; van der Meulen, Talitha; Vaughan, Joan M;

    2009-01-01

    Corticotropin-releasing factor (CRF), originally characterized as the principal neuroregulator of the hypothalamus-pituitary-adrenal axis, has broad central and peripheral distribution and actions. We demonstrate the presence of CRF receptor type 1 (CRFR1) on primary beta cells and show that...... MIN6 insulinoma line and primary rat islets with CRF also activates the MAPK signaling cascade leading to rapid phosphorylation of Erk1/2 in response to CRFR1-selective ligands, which induce proliferation in primary rat neonatal beta cells. Importantly, CRFR1 stimulates insulin secretion only during......1 on beta cells adds another layer of complexity to the intricate network of paracrine and autocrine factors and their cognate receptors whose coordinated efforts can dictate islet hormone output and regulate beta cell proliferation....

  12. Plan beta: Core or Cusp?

    CERN Document Server

    Richardson, Thomas; Lehnert, Matt

    2013-01-01

    The inner profile of Dark Matter (DM) halos remains one of the central problems in small-scale cosmology. At present, the problem can not be resolved in dwarf spheroidal galaxies due to a degeneracy between the DM profile and the velocity anisotropy beta of the stellar population. We discuss a method which can break the degeneracy by exploiting 3D positions and 1D line-of-sight (LOS) velocities. With the full 3D spatial information, we can determine precisely what fraction of each stars LOS motion is in the radial and tangential direction. This enables us to infer the anisotropy parameter beta directly from the data. The method is particularly effective if the galaxy is highly anisotropic. Finally, we argue that such a test could be applied to Sagittarius and potentially other dwarfs with RR Lyrae providing the necessary depth information.

  13. Beta spectrum of 185W

    International Nuclear Information System (INIS)

    The measurement of the shape of the first forbidden beta transition of 185W is interesting from the point of view of the fact that this nucleus belongs to the deformed region 150185W is carried out employing an optimized Siegbahn-Slatis beta ray spectrometer and the result is compared with the theoretical shape factor incorporating Nilsson's wavefunctions using Simms formalism. The experimental shape factor is fitted to the correction factor C(W)=k(1+aW) with α=0.0026+-0.0432. The theoretical shape factor computed following the matrix elements due to Nilsson model is in good agreement with the present experimental shape factor. The value Λ(2.358) computed in the present measurement in the light of Nilsson model matrix elements of 185W is in agreement with the predicted value (2.4) of J.J. Fujita. (author)

  14. Bootstrap method for characterizing the effect of uncertainty in shear strength parameters on slope reliability

    International Nuclear Information System (INIS)

    This paper aims to propose a bootstrap method for characterizing the effect of uncertainty in shear strength parameters on slope reliability. The procedure for a traditional slope reliability analysis with fixed distributions of shear strength parameters is presented first. Then, the variations of the mean and standard deviation of shear strength parameters and the Akaike Information Criterion values associated with various distributions are studied to characterize the uncertainties in distribution parameters and types of shear strength parameters. The reliability of an infinite slope is presented to demonstrate the validity of the proposed method. The results indicate that the bootstrap method can effectively model the uncertain probability distributions of shear strength parameters. The uncertain distributions of shear strength parameters have a significant influence on slope reliability. With the bootstrap method, the slope reliability index is represented by a confidence interval instead of a single fixed index. The confidence interval increases with increasing factor of slope safety. Considering both the uncertainties in distribution parameters and distribution types of shear strength parameters leads to a higher variation and a wider confidence interval of reliability index. - Highlights: • A bootstrap method is proposed to characterize effect of uncertainty on reliability. • An infinite slope is studied to demonstrate validity of bootstrap method. • The bootstrap method can effectively model uncertain probability distributions. • Slope reliability index is a confidence interval instead of a single fixed index. • Confidence interval of reliability index increases with increasing factor of safety

  15. The Mechanism of $\\beta$-Delayed Two-Proton Emission

    CERN Multimedia

    2002-01-01

    The nucleus $^{31}$Ar seems to be the most prolific ${\\beta}$-2p precursor known to date and is at the same time the one with the largest production yields at ISOLDE, where the most sensitive experiments can be done. Our purpose with this experiment is to study the ${\\beta}$-2p branches in detail, search for ${\\beta}$-3p events, place them in the decay scheme and obtain information on the decay mechanism for ${\\beta}$-2p via the energy distribution and the angular correlation between the two protons. As a by product we shall also resolve existing inconsistencies in the level scheme.\\\\ \\\\ The nucleus $^{31}$Ar, produced in a cold plasma ion source unit by the impact of a 1 GeV proton beam of 0.5 Hz frequency, had an average yield over one week of 1.5 $^{31}$Ar atoms/s. The beam passed through the central hole of an annular Si detector ($\\Omega$ = 4.3~\\%) and stopped in a thin carbon foil tilted 45$^o$ with respect to the beam direction. A 70~\\% coaxial HPGe-detector ($\\Omega$~=~7.4~\\%) was located opposite to ...

  16. An ISPA-camera for $\\beta$-radiography

    CERN Document Server

    Puertolas, D; Leutz, H; Gys, Thierry; D'Ambrosio, C

    1996-01-01

    We have developed a new type of beta-camera based on an Imaging Silicon Pixel Array (ISPA)-tube combined with planar plastic scintillators or with SiY2O5(Ce)-scintillating powder. The ISPA-tube consists of a photocathode viewed at 3 cm distance by a silicon anode divided into 1024 rectangular (75 microm x 500 microm) detector pixels, each bump-bonded to its equally-sized electronic pixel. Depending on the beta-detector thickness we achieved spatial resolutions (FWHM) between 105 microm (63Ni source and 30 microm thick plastic scintillator) and 240 microm (90Sr-90Y source and 120 microm thick plastic scintillator) by covering the detectors with brass templates. With their four 60 microm wide slits oriented parallel to the long pixel edges we simulated small sized beta-strips. The impact of detector thickness is explained by multiple scattering, angular aperture of the template slits and scintillating light distribution at the ISPA-photocathode. Beta detection sensitivities were measured with calibrated...

  17. Beta emitters and radiation protection

    DEFF Research Database (Denmark)

    Jødal, Lars

    2009-01-01

    , and 90Y, using data from a freely available database. Bremsstrahlung yields were calculated for 90Y shielded by lead, aluminium, or perspex. Bremsstrahlung spectrum from 90Y shielded by perspex was measured, and attenuation of spectrum by lead was calculated. Whole-body and finger doses to persons...... the outside of the primary shielding material. If suitable shielding is used and larger numbers of handlings are divided among several persons, then handling of beta emitters can be a safe procedure....

  18. Review of double beta experiments

    OpenAIRE

    Sarazin, X.

    2012-01-01

    C13-10-22.1 International audience This paper gives a review of the double beta experimental techniques and projects, in the search for the Majorana neutrino. The purpose of this review is to detail, for each technique, the different origins of background, how they can be identified, and how they can be reduced. Advantages and limitations of the different techniques are discussed. 1. Introduction The neutrino is one of the most puzzling elementary particle with very unique properties. I...

  19. Electrolytic hydrogen in beta titanium

    International Nuclear Information System (INIS)

    Permeation of electrolytic hydrogen through beta titanium foils with palladium coated surfaces was studied using Ti--11.5 Mo--6 Zr--4.5 Sn. Ion bombardment etching followed by thin film vapor deposition of palladium were used to produce oxide-free titanium specimens for electrochemical hydrogen permeation and embrittlement studies. A thin metallic foil is cathodically charged with hydrogen on one side while the other side is maintained at a sufficiently anodic potential so that all the diffusing hydrogen is oxidized and turned into an equivalent current. The current is analyzed to determine diffusivity and solubility of hydrogen. X-ray diffraction was also used to determine the effects of hydrogen on the lattice parameter. Permeation experiments conducted with basic cyanide solutions exhibited simple diffusion behavior. The diffusivity at 210C for hydrogen through the beta alloy was 5.60 (+-1.92) x 10-7 cm2/s. Anomalous permeation occurred with hydrogen chemical potentials in acidic and basic solutions without cyanide during the later stages of the approach to steady state in the charging. This behavior is consistent with the trapping model of hydrogen in metals of McNabb and Foster. Plastic deformation and spontaneous cracking at the wetted portion of the specimen were observed under extreme conditions during this anomalous behavior. Part of the deformation is found to be reversible. In the mandrel bend experiments on the embrittlement phenomenon, the transgranular cleavage mode of fracture occurred. Interstitially dissolved hydrogen expanded the bcc lattice of the beta titanium with accompanying diffraction line broadening. The lattice contracted upon removal of the hydrogen. The satisfactory performance of the beta alloy Ti--11.5 Mo--6 Zr--4.5 Sn, in moderate electrochemical environments results principally from the protective oxide film

  20. Neutrinoless Double Beta Decay Experiments

    OpenAIRE

    Zuber, K.

    2014-01-01

    Neutrinoless double beta decay is the only process known so far able to test the neutrino intrinsic nature: its experimental observation would imply that the lepton number is violated by two units and prove that neutrinos have a Majorana mass components, being their own anti-particle. While several experiments searching for such a rare decay have been performed in the past, a new generation of experiments using different isotopes and techniques have recently released their results or are taki...