Sample records for beta sources

  1. 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)


    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)

  2. Source preparations for alpha and beta measurements

    Energy Technology Data Exchange (ETDEWEB)

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


    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. Studies to confirm the source of 11 beta-hydroxyandrostenedione. (United States)

    Holownia, P; Owen, E J; Conway, G S; Round, J; Honour, J W


    In a longitudinal study of 82 children we found a gradual rise in median plasma concentrations of 11 beta-hydroxyandrostenedione (11 beta-OH-A4) from 2.5 to 6.4 nmol/l during childhood which was similar in both sexes. This could reflect changes in adrenal function during the adrenarche and sexual maturation. Plasma concentrations of 11 beta-OH-A4 in adults follow the patterns of cortisol secretion. In patients with diseases of the adrenal cortex, the plasma concentrations of 11 beta-OH-A4 were consistent with the pathology of each condition. In women with polycystic ovaries (PCO) undergoing gonadotrophic stimulation for in vitro fertilization and embryo transfer, 11 beta-OH-A4 (median = 3.8 nmol/l), testosterone and androstenedione, were raised when compared to women with normal ovaries (11 beta-OH-A4 median = 2.6 nmol/l). Follicular fluid has concentrations of 11 beta-OH-A4 six to twelve times greater than plasma levels and in women with PCO, 11 beta-OH-A4 concentrations were lower than in women with normal ovaries, which is consistent with an inhibition of ovarian 11 beta-hydroxylase. Granulosa cells in vitro demonstrated the production of 11 beta-OH-A4 by side chain cleavage of cortisol. These data support an adrenal source for 11 beta-OH-A4 but the raised plasma concentrations in women with polycystic ovary syndrome (PCOS) may reflect the excess androgen output from the ovary. 11 beta-OH-A4 may therefore be an additional marker for ovarian dysfunction.

  4. The genus Rhodosporidium: a potential source of beta-carotene. (United States)

    de Miguel, T; Calo, P; Díaz, A; Villa, T G


    Four wild-type species of the genus Rhodosporidium have been studied as as possible sources for the industrial production of beta-carotene. HPLC-based studies showed that their carotenoid composition consisted of almost pure beta-carotene at concentrations ranging from 226 to 685 micrograms/g of dried yeast biomass. These results are consistent with those obtained by spectrophotometry at 480 nm.

  5. A new irradiated quartz for beta source calibration

    DEFF Research Database (Denmark)

    Hansen, Vicki; Murray, Andrew Sean; Buylaert, Jan-Pieter;


    laboratories have used the various different batches of Risø calibration quartz for the calibration of beta and X-ray sources, but these have been largely undescribed. Here we describe in detail the preparation and luminescence characteristics of a new quartz standard, based on a North Sea beach sand collected...

  6. Elaboration of supports for beta emitting sources (with vyns); Elaboracion de soportes para fuentes emisoras beta (con vyns)

    Energy Technology Data Exchange (ETDEWEB)

    Cortes P, A.; Torre O, J. De la; Tejera R, A.; Becerril V, A.; Bribiesca S, L


    The Laboratory of Radioactive patterns account with a 4 {pi}{beta}-{gamma} coincidence system of recent acquisition with which absolute measures of radioactive activity with uncertainties of the order of 0.1% can be made. Since the coincidence method for the activity measure consists on detecting to the particle and the photon corresponding to oneself nuclear disintegration, it is necessary to elaborate special radioactive sources on thin supports, in order to allowing the maximum possible fluence of {beta} particles ({approx} 100%). This work a technique for the elaboration of these sources and for the measure of the thickness of the walls of the support is presented. (Author)

  7. 2$\\pi$ proportional counting chamber for large-area-coated $\\beta$ sources

    Indian Academy of Sciences (India)



    Detection system for measuring absolute emission rate from large-area-coated $\\beta$ sources has been indigenously developed. The system consists of a multiwire-based proportional counter with gas flow and a source mounted within the sensitive volume of the detector. Design of the counter enables efficient counting of emissions in $2\\pi$ solid angle.A provision is made for change ofthe source and immediate measurement of source activity. These sources are used to calibrate the efficiency of contamination monitors at radiological facilities. Sensitive area of the detector covers 165◦ solid angle nearing $2\\pi$ of emission from the source of size $100 \\times 150$ mm. Performance of the chamber is tested using collimated $^{55}$Fe X-ray source and $^{90}$Sr / $^{90}$Y coated $\\beta$ sources of various activities. The activity measurement system is established as a national primary standard for calibration of coated $\\beta$ sources at Radiological Laboratory at BARC. Design and performanceof the chamber are presented.

  8. Beta4 tubulin identifies a primitive cell source for oligodendrocytes in the mammalian brain. (United States)

    Wu, Chuanshen; Chang, Ansi; Smith, Maria C; Won, Roy; Yin, Xinghua; Staugaitis, Susan M; Agamanolis, Dimitri; Kidd, Grahame J; Miller, Robert H; Trapp, Bruce D


    We have identified a novel population of cells in the subventricular zone (SVZ) of the mammalian brain that expresses beta4 tubulin (betaT4) and has properties of primitive neuroectodermal cells. betaT4 cells are scattered throughout the SVZ of the lateral ventricles in adult human brain and are significantly increased in the SVZs bordering demyelinated white matter in multiple sclerosis brains. In human fetal brain, betaT4 cell densities peak during the latter stages of gliogenesis, which occurs in the SVZ of the lateral ventricles. betaT4 cells represent 95% of cells in neurospheres treated with the anti-mitotic agent Ara C. betaT4 cells produce oligodendrocytes, neurons, and astrocytes in vitro. We compared the myelinating potential of betaT4-positive cells with A2B5-positive oligodendrocyte progenitor cells after transplantation (25,000 cells) into postnatal day 3 (P3) myelin-deficient rat brains. At P20, the progeny of betaT4 cells myelinated up to 4 mm of the external capsule, which significantly exceeded that of transplanted A2B5-positive progenitor cells. Such extensive and rapid mature CNS cell generation by a relatively small number of transplanted cells provides in vivo support for the therapeutic potential of betaT4 cells. We propose that betaT4 cells are an endogenous cell source that can be recruited to promote neural repair in the adult telencephalon.

  9. Gross-beta activity in ground water: natural sources and artifacts of sampling and laboratory analysis (United States)

    Welch, Alan H.


    Gross-beta activity has been used as an indicator of beta-emitting isotopes in water since at least the early 1950s. Originally designed for detection of radioactive releases from nuclear facilities and weapons tests, analysis of gross-beta activity is widely used in studies of naturally occurring radioactivity in ground water. Analyses of about 800 samples from 5 ground-water regions of the United States provide a basis for evaluating the utility of this measurement. The data suggest that measured gross-beta activities are due to (1) long-lived radionuclides in ground water, and (2) ingrowth of beta-emitting radionuclides during holding times between collection of samples and laboratory measurements.Although40K and228Ra appear to be the primary sources of beta activity in ground water, the sum of40K plus228Ra appears to be less than the measured gross-beta activity in most ground-water samples. The difference between the contribution from these radionuclides and gross-beta activity is most pronounced in ground water with gross-beta activities > 10 pCi/L, where these 2 radionuclides account for less than one-half the measured ross-beta activity. One exception is groundwater from the Coastal Plain of New Jersey, where40K plus228Ra generally contribute most of the gross-beta activity. In contrast,40K and228Ra generally contribute most of beta activity in ground water with gross-beta activities measure all beta activity in ground water. Although3H contributes beta activity to some ground water, it is driven from the sample before counting and therefore is not detected by gross-beta measurements. Beta-emitting radionuclides with half-lives shorter than a few days can decay to low values between sampling and counting. Although little is known about concentrations of most short-lived beta-emitting radionuclides in environmental ground water (water unaffected by direct releases from nuclear facilities and weapons tests), their activities are expected to be low.Ingrowth of

  10. Evaluation of the beta energy spectrum from a distributed uranium mill tailings source. (United States)

    Reif, R H; Martz, D E; Carlson, D S; Turner, J B


    The beta energy spectra from uranium mill tailings, 90Sr with different absorber thicknesses, and a uranium metal slab were measured and compared to select an appropriate beta source for calibrating a personal dosimeter to measure shallow dose equivalent when exposed to uranium mill tailings. The measured beta energy spectrum from the 90Sr source, with a 111 mg cm-2 cover thickness, was selected as a possible calibration source for a personnel dosimeter. The dose equivalent rate to the skin at 1 cm from a distributed tailings source of infinite thickness, with a 226Ra activity of 56 Bq g-1 (1.5 x 10(3) pCi g-1), was measured to be 0.024 mSv h-1 (2.4 mrem h-1).

  11. Factors affecting quality for beta dose rate measurements using ISO 6980 series I reference sources

    Energy Technology Data Exchange (ETDEWEB)

    Burns, R.E. Jr.; O`Brien, J.M. Jr. [Atlan-Tech, Rosewll, GA (United States)


    Atlan-Tech, Inc. has performed several calibrations of ISO 6980 Series 1 reference beta sources over the past two to three years. There were many problems encountered in attempting to compare the results of these calibrations with those from other laboratories, indicating the need for more standardization in the methodology employed for the measurement of the absorbed dose rate from ISO 6980 Series 1 reference beta sources. This document describes some of the problems encountered in attempting to intercompare results of beta dose-rate measurements. It proposes some solutions in an attempt to open a dialogue among facilities using reference beta standards for the purpose of promoting better measurement quality assurance through data intercomparison.

  12. Investigation of the effect of beta source and phosphors on photovoltaic cells (United States)

    Yürük, Reyyan Kavak; Tütüncüler, Hayriye


    In this study, conversion of kinetic energy from the decay of a radioactive isotope to electricity is investigated by using the direct and the indirect conversion methods. In this context, simple nuclear battery models are designed. Analysis for the effect of low-activity radiation from Pm147 and Sr90 beta sources on photovoltaic Si solar cell is presented. Beta radioluminescence nuclear battery models consist of a beta source, a phosphor layer and a solar cell. Phosphor layers with different mass thicknesses are prepared from ZnS:CuCl and SrAl2O4:Eu2+,Dy3+ phosphors. Both the influence of beta sources and the phosphor layers on battery performance is analyzed separately. Effect of beta sources, phosphors are observed on solar cell by measuring the short circuit current and open circuit voltage. The efficiency of the battery models is determined with the obtained results. Furthermore, short circuit current values are analyzed at various times during the irradiation.

  13. Stem cells to pancreatic beta-cells: new sources for diabetes cell therapy. (United States)

    Guo, Tingxia; Hebrok, Matthias


    The number of patients worldwide suffering from the chronic disease diabetes mellitus is growing at an alarming rate. Insulin-secreting beta-cells in the islet of Langerhans are damaged to different extents in diabetic patients, either through an autoimmune reaction present in type 1 diabetic patients or through inherent changes within beta-cells that affect their function in patients suffering from type 2 diabetes. Cell replacement strategies via islet transplantation offer potential therapeutic options for diabetic patients. However, the discrepancy between the limited number of donor islets and the high number of patients who could benefit from such a treatment reflects the dire need for renewable sources of high-quality beta-cells. Human embryonic stem cells (hESCs) are capable of self-renewal and can differentiate into components of all three germ layers, including all pancreatic lineages. The ability to differentiate hESCs into beta-cells highlights a promising strategy to meet the shortage of beta-cells. Here, we review the different approaches that have been used to direct differentiation of hESCs into pancreatic and beta-cells. We will focus on recent progress in the understanding of signaling pathways and transcription factors during embryonic pancreas development and how this knowledge has helped to improve the methodology for high-efficiency beta-cell differentiation in vitro.

  14. Developing a beta source based setup for pixel sensor characterization

    CERN Document Server

    Schouwenberg, Jeroen


    The main goal of this project is to provide mono-energetic minimum ionizing electrons from a $^{90}$Sr source using a magnetic monochromator, and thus provide a useful tool for in-lab sensor characterization. The monochromator is calibrated using a setup, with a heavy inorganic scintillator and a PMT, which has been calibrated with a $^{22}$Na gamma source. The average energy of the electrons as a function of the current in the monochromator coil is found to be $1.38\\pm0.01$ keV/mA, taking into consideration the effect of the magnetic field on the signal of the PMT. For integration into the pixel sensor test bench, scintillator-counters (a plastic scintillator connected to a PMT) are used. Their response to the electron energies is observed to follow a saturation curve, which leads to a more identical response for high energetic electrons. A preliminary pixel sensor test bench has been set up and properties such as voltage and discriminator settings have been studied as well as count rates for coincidence cou...

  15. Procedure for the elaboration of extended sources beta and/or gamma emitting; Procedimiento para la elaboracion de fuentes extendidas emisoras beta y/o gamma

    Energy Technology Data Exchange (ETDEWEB)

    Tejera R, A.; Cortes P, A.; Becerril V, A


    In the laboratory of radioactive standards they have been come manufacturing punctual sources gauged gamma emitting during several years. Before the demand of extended radioactive homogeneous sources of beta particles emitting, in particular with nuclides that are simultaneously gamma and beta emitting, it was designed a procedure for it elaboration based on the one that we use at the moment for the elaboration of the punctual gamma sources. This procedure consists on the integration of a compact group of this type of sources on a single extended support, sealed one of its faces with a film of transparent material in satisfactory grade to the beta particles. In this work this procedure is described and it is applied in the elaboration of two sources that its were requested by the Laguna Verde Central (CFE), one with area of 20 cm{sup 2} and the other one of 100 cm{sup 2}. The homogeneity, measure as the dispersion of the activities of the aliquot ones distributed in the active surfaces was inside 2%. The percentage of attenuation of the beta particles was also measured by the film (window) with the one that the sources were sealed. (Author)

  16. Radioactivity determination of sealed pure beta-sources by surface dose measurements and Monte Carlo simulations

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chang Heon [Interdisciplinary Program in Radiation Applied Life Science, Seoul National University College of Medicine, Seoul (Korea, Republic of); Jung, Seongmoon [Program in Biomedical Radiation Sciences, Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul (Korea, Republic of); Choi, Kanghyuk; Son, Kwang-Jae; Lee, Jun Sig [Hanaro Applications Research, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Ye, Sung-Joon, E-mail: [Interdisciplinary Program in Radiation Applied Life Science, Seoul National University College of Medicine, Seoul (Korea, Republic of); Program in Biomedical Radiation Sciences, Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul (Korea, Republic of); Center for Convergence Research on Robotics, Advance Institutes of Convergence Technology, Seoul National University, Suwon (Korea, Republic of)


    This study aims to determine the activity of a sealed pure beta-source by measuring the surface dose rate using an extrapolation chamber. A conversion factor (cGy s{sup −1} Bq{sup −1}), which was defined as the ratio of surface dose rate to activity, can be calculated by Monte Carlo simulations of the extrapolation chamber measurement. To validate this hypothesis the certified activities of two standard pure beta-sources of Sr/Y-90 and Si/P-32 were compared with those determined by this method. In addition, a sealed test source of Sr/Y-90 was manufactured by the HANARO reactor group of KAERI (Korea Atomic Energy Research Institute) and used to further validate this method. The measured surface dose rates of the Sr/Y-90 and Si/P-32 standard sources were 4.615×10{sup −5} cGy s{sup −1} and 2.259×10{sup −5} cGy s{sup −1}, respectively. The calculated conversion factors of the two sources were 1.213×10{sup −8} cGy s{sup −1} Bq{sup −1} and 1.071×10{sup −8} cGy s{sup −1} Bq{sup −1}, respectively. Therefore, the activity of the standard Sr/Y-90 source was determined to be 3.995 kBq, which was 2.0% less than the certified value (4.077 kBq). For Si/P-32 the determined activity was 2.102 kBq, which was 6.6% larger than the certified activity (1.971 kBq). The activity of the Sr/Y-90 test source was determined to be 4.166 kBq, while the apparent activity reported by KAERI was 5.803 kBq. This large difference might be due to evaporation and diffusion of the source liquid during preparation and uncertainty in the amount of weighed aliquot of source liquid. The overall uncertainty involved in this method was determined to be 7.3%. We demonstrated that the activity of a sealed pure beta-source could be conveniently determined by complementary combination of measuring the surface dose rate and Monte Carlo simulations.

  17. Development of A phantom for ophthalmic beta source applicator quality control using TL dosimetry (United States)

    Barbosa, N. A.; da Rosa, L. A. R.; Braz, D.


    Concave eye applicators with 90Sr/90Y and 106Ru/106Rh beta ray sources are usually used in brachytherapy for the treatment of superficial intraocular tumors as uveal melanoma with thickness up to 5 mm. The calculation of the dose delivered to the eye is carried out based on the data present in the beta source calibration certificate. Therefore, it would be interesting to have a system that could evaluate that dose. In this work, an eye phantom to be used with 106Ru/106Rh betatherapy applicators was developed in solid water. This phantom can hold nine micro-cube thermoluminescent (TL) dosimeters, TLD-100. The characteristics of the TL response of the dosimeters, namely reproducibility and individual sensitivity, were determined for a 60Co source. Using Monte Carlo code MCNPX, the dose to a water eye was determined at different depths. Exposing the eye phantom with TL dosimeters to the 106Ru/106Rh applicator, it is possible to assess calibration factors using the dose values obtained by Monte Carlo simulation to each depth. Using mean calibration factors, dose values obtained by TL dosimetry were compared to the data present in the applicators certificate. Mean differences for both applicators were lower than ±10%, maximum value 17% and minimum value 0.08%. Considering that the certificate values present an uncertainty of ±20%, the calibration procedure and the developed phantom are validated and can be applied.

  18. Response-surface models for deterministic effects of localized irradiation of the skin by discrete {beta}/{gamma} -emitting sources

    Energy Technology Data Exchange (ETDEWEB)

    Scott, B.R.


    Individuals who work at nuclear reactor facilities can be at risk for deterministic effects in the skin from exposure to discrete {Beta}- and {gamma}-emitting ({Beta}{gamma}E) sources (e.g., {Beta}{gamma}E hot particles) on the skin or clothing. Deterministic effects are non-cancer effects that have a threshold and increase in severity as dose increases (e.g., ulcer in skin). Hot {Beta}{gamma}E particles are {sup 60}Co- or nuclear fuel-derived particles with diameters > 10 {mu}m and < 3 mm and contain at least 3.7 kBq (0.1 {mu}Ci) of radioactivity. For such {Beta}{gamma}E sources on the skin, it is the beta component of the dose that is most important. To develop exposure limitation systems that adequately control exposure of workers to discrete {Beta}{gamma}E sources, models are needed for systems that adequately control exposure of workers to discrete {Beta}{gamma}E sources, models are needed for evaluating the risk of deterministic effects of localized {Beta} irradiation of the skin. The purpose of this study was to develop dose-rate and irradiated-area dependent, response-surface models for evaluating risks of significant deterministic effects of localized irradiation of the skin by discrete {Beta}{gamma}E sources and to use modeling results to recommend approaches to limiting occupational exposure to such sources. The significance of the research results as follows: (1) response-surface models are now available for evaluating the risk of specific deterministic effects of localized irradiation of the skin; (2) modeling results have been used to recommend approaches to limiting occupational exposure of workers to {Beta} radiation from {Beta}{gamma}E sources on the skin or on clothing; and (3) the generic irradiated-volume, weighting-factor approach to limiting exposure can be applied to other organs including the eye, the ear, and organs of the respiratory or gastrointestinal tract and can be used for both deterministic and stochastic effects.

  19. Electrodeposition Techniques for the Preparation of Beta-Sprectroscopy Sources of Rare-Earth Elements

    DEFF Research Database (Denmark)

    Hansen, P. Gregers; Høgh, J.; Nielsen, H. L.


    Thin, uniform radioactive deposits of rare earths and related elements can be prepared by cathodic electrodeposition of their hydroxides. The main theoretical and experimental features of this process are reviewed and plating cell design and the choice of conditions are described together...... with the associated radio-chemical methods. The use of copper-backed nickel films is shown to allow the preparation of beta sources on quite thin (down to 45 μg cm−2) backings, if the copper layer is etched selectively after the radioactivity has been plated onto the nickel....

  20. Beta-globin haplotype analysis suggests that a major source of Malagasy ancestry is derived from Bantu-speaking Negroids.


    Hewitt, R.; Krause, A.; Goldman, A; Campbell, G.; Jenkins, T


    The origins of the inhabitants of Madagascar have not been fully resolved. Anthropological studies and preliminary genetic data point to two main sources of ancestry of the Malagasy, namely, Indonesian and African, with additional contributions from India and Arabia. The sickle-cell (beta s) mutation is found in populations of African and Indian origin. The frequency of the beta s-globin gene, derived from 1,425 Malagasy individuals, varies from 0 in some highland populations to .25 in some c...

  1. Tests of MVD prototype pad detector with a beta sup - source

    CERN Document Server

    Yeol-Kim, S; SuRyu, S; Hwan-Kang, J; Simon-Gillo, J; Sullivan, J P; Heck, H W V; Xu Guang Hu


    The MVD group has been testing two versions of silicon pad detectors. One design uses a single metal layer for readout trace routing. The second type uses two layers of metal, allowing for greatly simplified signal routing. However, because the readout traces for the pads pass over the other pads in the same column (separated by an oxide layer), the double-metal design introduces crosstalk into the system. A simple test stand using a sup 9 sup 0 Sr beta sup - source with scintillator triggers was made to estimate the crosstalk. The crosstalk between pads in the same column of the pad detector was 1.6-3.1%. The values measured between pads in different columns were very close to zero. The measured crosstalk was below our maximum allowed value of 7.8%.

  2. Beta-globin haplotype analysis suggests that a major source of Malagasy ancestry is derived from Bantu-speaking Negroids. (United States)

    Hewitt, R; Krause, A; Goldman, A; Campbell, G; Jenkins, T


    The origins of the inhabitants of Madagascar have not been fully resolved. Anthropological studies and preliminary genetic data point to two main sources of ancestry of the Malagasy, namely, Indonesian and African, with additional contributions from India and Arabia. The sickle-cell (beta s) mutation is found in populations of African and Indian origin. The frequency of the beta s-globin gene, derived from 1,425 Malagasy individuals, varies from 0 in some highland populations to .25 in some coastal populations. The beta s mutation is thought to have arisen at least five times, on the basis of the presence of five distinct beta s-associated haplotypes, each found in a separate geographic area. Twenty-five of the 35 Malagasy beta s haplotypes were of the typical "Bantu" type, 1 "Senegal" haplotype was found, and 2 rare or atypical haplotypes were observed; the remaining 7 haplotypes were consistent with the Bantu haplotype. The Bantu beta s mutation is thought to have been introduced into Madagascar by Bantu-speaking immigrants (colonists or slaves) from central or east Africa. The Senegal beta s mutation may have been introduced to the island via Portuguese naval explorers. This study provides the first definitive biological evidence that a major component of Malagasy ancestry is derived from African populations, in particular, Bantu-speaking Negroids. beta A haplotypes are also consistent with the claim for a significant African contribution to Malagasy ancestry but are also suggestive of Asian/Oceanic and Caucasoid admixture within the Malagasy population.

  3. Effects of carbon source and Vitreoscilla hemoglobin (VHb) on the production of beta-galactosidase in Enterobacter aerogenes. (United States)

    Khleifat, Khaled M; Abboud, Muayad M; Al-Mustafa, Ahmed H; Al-Sharafa, Khalid Y


    At fixed concentration (0.5%), lactose and galactose acted as inducers while glucose and other tested carbon sugars showed repression effects on beta-galactosidase production in Enterobacter aerogenes strain. The expression of Vitreoscilla hemoglobin gene (vgb) in this bacterial strain managed to overcome the repression effects as well as improving the induction of beta-galactosidase formation by carbon sources. In parallel, the bacterial O(2) consumption was increased correspondingly to the vgb induction of beta-galactosidase synthesis. When Enterobacter aerogenes strains were grown at the incubation temperature 42 degrees C, about 5-fold higher enzyme productivity was obtained than with a similar incubation at 37 degrees C. The bacterial growth expressed as biomass yield had a different optimum temperature and was not influenced to the same extent by variations in the carbon sources. These data are discussed in terms of proposed enhancement in beta-galactosidase productivity by vgb expression as well as its significance to improve the technology of whey processing.

  4. The influence of precursor source and thermal parameters upon the formation of beta-phase molybdenum nitride

    Energy Technology Data Exchange (ETDEWEB)

    Cairns, A.G.; Gallagher, J.G. [WestCHEM, Department of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Hargreaves, J.S.J. [WestCHEM, Department of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom)], E-mail:; Mckay, D.; Morrison, E. [WestCHEM, Department of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Rico, J.L. [Laboratorio de Catalisis, Facultad de Ingenieria Quimica, Universidad Michoacana, Edificio E, CU, Morelia Mich, C.P. 58060 (Mexico)], E-mail:; Wilson, K. [WestCHEM, Department of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom)


    In the present paper the effect of the MoO{sub 3} precursor and procedure on the synthesis of beta-phase molybdenum nitride is reported. Two different sources of MoO{sub 3} were used, and treated under a flow of gas N{sub 2}/H{sub 2} at 700 or 750 deg. C employing various heating ramp rates. All samples were characterized by XRD, SEM and their textural properties were determined by application of the BET method. The results show that, depending on the precursor, markedly different morphologies were observed, whereas both the molybdenum source and the thermal treatment, strongly influence the incorporation of nitrogen.

  5. Determination of half-value thickness of aluminum foils for different beta sources by using fractional calculus

    Energy Technology Data Exchange (ETDEWEB)

    Şen, Mürsel, E-mail: [Department of Physics, Institute of Science and Technology, Dumlupınar University, Kütahya 43100 (Turkey); Çalık, Abdullah Engin, E-mail: [Department of Physics, Arts and Sciences Faculty, Dumlupınar University, Kütahya 43100 (Turkey); Ertik, Hüseyin, E-mail: [Department of Mathematics Education, Alanya Faculty of Education, Akdeniz University, Alanya, Antalya 07425 (Turkey)


    Reduction of beta-ray intensity with respect to thickness of absorber material exhibits a non-exponential behavior due to the different types of the energy loss processes and many different fractal-like paths followed by beta particles in material. According to Caputo formalism of fractional calculus, the reduction process of beta-ray intensity is governed by using a simple fractional differential equation of order α ≈ 0.31. The solution is obtained in terms of Mittag–Leffler function which depends on a mass attenuation coefficient μ{sub m} and a fractional order α that can be considered as a measure of fractality of absorbing material. In the experimental part of the study, {sup 99}Tc, {sup 36}Cl, {sup 14}C, {sup 210}Pb and {sup 147}Pm radioisotopes have been used as beta sources. In the framework of fractional calculus approach, the experimental and calculated half-value thicknesses of all samples have been obtained in agreement with each other.

  6. Microglia and macrophages are major sources of locally produced transforming growth factor-beta1 after transient middle cerebral artery occlusion in rats

    DEFF Research Database (Denmark)

    Lehrmann, E; Kiefer, R; Christensen, Thomas


    source of TGF-beta1 mRNA following experimental focal cerebral ischemia. Consequently, TGF-beta1-mediated functions may be exerted by microglia both in the early degenerative phase, and later in combination with blood-borne macrophages, in the remodeling and healing phase after focal cerebral ischemia....

  7. Laser and beta source setup characterization of 3D-DDTC detectors fabricated at FBK-irst

    Energy Technology Data Exchange (ETDEWEB)

    Zoboli, A. [INFN, Sezione di Padova (Gruppo Collegato di Trento), and Dipartimento di Ingegneria e Scienza dell' Informazione, Universita di Trento, Via Sommarive, 14, I-38050 Povo (Trento) (Italy)], E-mail:; Dalla Betta, G.-F. [INFN, Sezione di Padova (Gruppo Collegato di Trento), and Dipartimento di Ingegneria e Scienza dell' Informazione, Universita di Trento, Via Sommarive, 14, I-38050 Povo (Trento) (Italy); Boscardin, M. [Fondazione Bruno Kessler, Centro per i Materiali e i Microsistemi, Via Sommarive, 18, I-38050 Povo (Trento) (Italy); Bosisio, L. [Dip. di Fisica e INFN, Universita di Trieste, I-34127, Trieste (Italy); Eckert, S.; Kuehn, S.; Parzefall, U. [Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg (Germany); Piemonte, C.; Ronchin, S.; Zorzi, N. [Fondazione Bruno Kessler, Centro per i Materiali e i Microsistemi, Via Sommarive, 18, I-38050 Povo (Trento) (Italy)


    We report on the functional characterization of the first batch of 3D Double-Sided Double Type Column (3D-DDTC) detectors fabricated at FBK, Trento. This detector concept represents the evolution of the previous 3D-STC detectors towards full 3D detectors, and is expected to achieve a performance which is comparable to standard 3D detectors, but with a simpler fabrication process. Measurements were performed on detectors in the microstrip configuration coupled to the ATLAS ABCD3T binary readout. This paper reports spatially resolved signal efficiency tests made with a pulsed infrared laser setup and charge collection efficiency tests made with a Beta source.

  8. Source analysis of beta-synchronisation and cortico-muscular coherence after movement termination based on high resolution electroencephalography.

    Directory of Open Access Journals (Sweden)

    Muthuraman Muthuraman

    Full Text Available We hypothesized that post-movement beta synchronization (PMBS and cortico-muscular coherence (CMC during movement termination relate to each other and have similar role in sensorimotor integration. We calculated the parameters and estimated the sources of these phenomena.We measured 64-channel EEG simultaneously with surface EMG of the right first dorsal interosseus muscle in 11 healthy volunteers. In Task1, subjects kept a medium-strength contraction continuously; in Task2, superimposed on this movement, they performed repetitive self-paced short contractions. In Task3 short contractions were executed alone. Time-frequency analysis of the EEG and CMC was performed with respect to the offset of brisk movements and averaged in each subject. Sources of PMBS and CMC were also calculated.High beta power in Task1, PMBS in Task2-3, and CMC in Task1-2 could be observed in the same individual frequency bands. While beta synchronization in Task1 and PMBS in Task2-3 appeared bilateral with contralateral predominance, CMC in Task1-2 was strictly a unilateral phenomenon; their main sources did not differ contralateral to the movement in the primary sensorimotor cortex in 7 of 11 subjects in Task1, and in 6 of 9 subjects in Task2. In Task2, CMC and PMBS had the same latency but their amplitudes did not correlate with each other. In Task2, weaker PMBS source was found bilaterally within the secondary sensory cortex, while the second source of CMC was detected in the premotor cortex, contralateral to the movement. In Task3, weaker sources of PMBS could be estimated in bilateral supplementary motor cortex and in the thalamus. PMBS and CMC appear simultaneously at the end of a phasic movement possibly suggesting similar antikinetic effects, but they may be separate processes with different active functions. Whereas PMBS seems to reset the supraspinal sensorimotor network, cortico-muscular coherence may represent the recalibration of cortico-motoneuronal and

  9. Pairwise beta diversity resolves an underappreciated source of confusion in calculating species turnover. (United States)

    Marion, Zachary H; Fordyce, James A; Fitzpatrick, Benjamin M


    Beta diversity is an important metric in ecology quantifying differentiation or disparity in composition among communities, ecosystems, or phenotypes. To compare systems with different sizes (N, number of units within a system), beta diversity is often converted to related indices such as turnover or local/regional differentiation. Here we use simulations to demonstrate that these naive measures of dissimilarity depend on sample size and design. We show that when N is the number of sampled units (e.g., quadrats) rather than the "true" number of communities in the system (if such exists), these differentiation measures are biased estimators. We propose using average pairwise dissimilarity as an intuitive solution. That is, instead of attempting to estimate an N-community measure, we advocate estimating the expected dissimilarity between any random pairs of communities (or sampling units)-especially when the "true" N is unknown or undefined. Fortunately, measures of pairwise dissimilarity or overlap have been used in ecology for decades, and their properties are well known. Using the same simulations, we show that average pairwise metrics give consistent and unbiased estimates regardless of the number of survey units sampled. We advocate pairwise dissimilarity as a general standardization to ensure commensurability of different study systems. This article is protected by copyright. All rights reserved.

  10. Sources of alpha-, beta-, gamma-, delta- and epsilon-carotenes: a twentieth century review Fontes de alfa-, beta-, gama-, delta-, e epsilon-carotenos: uma revisão do século XX


    José M. Barbosa-Filho; Adriana A. Alencar; Nunes,Xirley P.; Anna C. de Andrade Tomaz; José G. Sena-Filho; Athayde-Filho, Petrônio F.; Silva, Marcelo S.; Maria F. Vanderlei de Souza; Emidio V. Leitão da-Cunha


    Since humans cannot synthesize carotenoids, they depend upon the diet exclusively for the source of these micronutrients. It has claimed that they may alleviate chronic diseases such as cancers. The present communication constitutes a global review of the scientific literature on plants and others organisms that biosynthesize carotenoids, which include the series alpha-, beta-, gamma-, delta- and epsilon-carotenes. The results of the literature survey lists more than five hundred sources.Uma ...

  11. Interlaboratory beta source calibration using TL and OSL on natural quartz

    DEFF Research Database (Denmark)

    Goksu. H.Y.; Bailiff, I.K.; Bøtter-Jensen, L.


    Laboratory at GSF using a Go-60 source as well as the in situ measurements with an ionization chamber, calibrated to the primary standards of PTB Braunschweig. Irradiated and unirradiated quartz was distributed to the five laboratories and although different procedures were used for thermoluminescence...

  12. Determination of the dose rapidity of a {sup 90} Sr beta radiation source using thermoluminescent dosemeters; Determinacion de la rapidez de dosis de una fuente de radiacion beta de {sup 90}Sr usando dosimetros termoluminiscentes

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez M, P.R.; Azorin N, J.; Rivera M, T. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)


    The thermoluminescent dosemeters developed in Mexico, have been used efficiently in environmental and personal dosimetry. When the dose rate of some source is not known can be estimated with the use of thermoluminescent dosemeters taking in account the geometrical array used in the irradiations for reproducibility of the results in posterior irradiations. In this work it was estimated the dose rate of a {sup 90} Sr-{sup 90} Y beta radiation source which is property of the Nuclear Sciences Institute, UNAM, therefore it was l ended to the Metropolitan Autonomous University- Iztapalapa Unit for the characterization of new Tl materials, taking account of the institutional collaboration agreements. (Author)

  13. Low dose beta-emitter source induces sexual reproduction instead of fragmentation in an earthworm, Enchytraeus japonensis. (United States)

    Miyachi, Yukihisa; Kanao, Tomoko; Okamoto, Takehito


    We examined whether background radiation, or radiation at a slightly higher level, plays a role in the reproduction of a terrestrial earthworm. Enchytraeus japonensis a recently described terrestrial oligochaete, reproduces asexually by fragmentation and subsequent regeneration. Following radiation exposure in which the worms were subjected to a 32P beta-emitter source at 15 times the background dose rate (4.5 microGy/h), a statistically significant decrease in the number of fragmentations was observed as compared with the sham controls. At that time, in a stained preparation with haematoxylin and eosin (HE), sexual reproduction occurred instead of asexual fragmentation, and mature oocytes were observed in the body of grown worms. However, increasing the radiation dose rate by 30 microGy/h resulted in the complete disappearance of the radiation-induced effects, i.e., fragmentation again occurred after 14 h. The results of this study indicate that a lower dose of radiation may be essential to achieve sexual reproduction, inducing an inhibition of fragmentation (asexual reproduction), but at higher, more cytotoxic doses of radiation these effects are negated.

  14. Low dose {beta}-emitter source induces sexual reproduction instead of fragmentation in an earthworm, Enchytraeus japonensis

    Energy Technology Data Exchange (ETDEWEB)

    Miyachi, Yukihisa E-mail:; Kanao, Tomoko; Okamoto, Takehito


    We examined whether background radiation, or radiation at a slightly higher level, plays a role in the reproduction of a terrestrial earthworm. Enchytraeus japonensis a recently described terrestrial oligochaete, reproduces asexually by fragmentation and subsequent regeneration. Following radiation exposure in which the worms were subjected to a {sup 32}P {beta}-emitter source at 15 times the background dose rate (4.5 {mu}Gy/h), a statistically significant decrease in the number of fragmentations was observed as compared with the sham controls. At that time, in a stained preparation with haematoxylin and eosin (HE), sexual reproduction occurred instead of asexual fragmentation, and mature oocytes were observed in the body of grown worms. However, increasing the radiation dose rate by 30 {mu}Gy/h resulted in the complete disappearance of the radiation-induced effects, i.e., fragmentation again occurred after 14 h. The results of this study indicate that a lower dose of radiation may be essential to achieve sexual reproduction, inducing an inhibition of fragmentation (asexual reproduction), but at higher, more cytotoxic doses of radiation these effects are negated.

  15. Chromosomal integration of a cephalosporinase gene from Acinetobacter baumannii into Oligella urethralis as a source of acquired resistance to beta-lactams. (United States)

    Mammeri, Hedi; Poirel, Laurent; Mangeney, Nicole; Nordmann, Patrice


    Clinical Oligella urethralis isolate COH-1, which was uncommonly resistant to penicillins and narrow-spectrum cephalosporins, was recovered from a 55-year-old patient with a urinary tract infection. Shotgun cloning into Escherichia coli and expression experiments gave recombinant clones expressing either an AmpC beta-lactamase-type phenotype of resistance or a carbenicillin-hydrolyzing beta-lactamase-type phenotype of resistance. The AmpC beta-lactamase identified (ABA-1), which had a pI value of 8.2, had 98% amino acid identity with a chromosomally encoded cephalosporinase of Acinetobacter baumannii. A 820-bp insertion sequence element, ISOur1, belonging to the IS6 family of insertion sequence elements, was identified immediately upstream of bla(ABA-1), providing a -35 promoter sequence and likely giving rise to a hybrid promoter region. The carbenicillin-hydrolyzing beta-lactamase identified (CARB-8), which had a pI value of 6.4, differed from CARB-5 by two amino acid substitutions. Hybridization of CeuI fragment I-restricted DNA fragments of O. urethralis COH-1 with bla(ABA-1)-, bla(CARB-8)-, and 16S rRNA-specific probes indicated the chromosomal integration of the beta-lactamase genes. PCR and hybridization experiments failed to detect bla(CARB-8)- and bla(ABA-1)-like genes in three O. urethralis reference strains, indicating that the beta-lactamase genes identified were the source of acquired resistance in O. urethralis COH-1. This is one of the few examples of the interspecies transfer and the chromosomal integration of a gene encoding a naturally occurring beta-lactamase.

  16. Extended-Spectrum beta (β)-Lactamases and Antibiogram in Enterobacteriaceae from Clinical and Drinking Water Sources from Bahir Dar City, Ethiopia


    Abera, Bayeh; Kibret, Mulugeta; Mulu, Wondemagegn


    Background The spread of Extended-Spectrum beta (β)-Lactamases (ESBL)-producing Enterobacteriaceae has become a serious global problem. ESBL-producing Enterobacteriaceae vary based on differences in antibiotic use, nature of patients and hospital settings. This study was aimed at determining ESBL and antibiogram in Enterobacteriaceae isolates from clinical and drinking water sources in Bahir Dar City, Northwest Ethiopia. Methods Enterobacteriaceae species were isolated from clinical materials...

  17. Monte Carlo-based Spencer-Attix and Bragg-Gray tissue-to-air stopping power ratios for ISO beta sources. (United States)

    Selvam, T Palani; Vandana, S; Bakshi, A K; Babu, D A R


    Spencer-Attix (SA) and Bragg-Gray (BG) mass-collision-stopping-power ratios of tissue-to-air are calculated using a modified version of EGSnrc-based SPRRZnrc user-code for the International Organization for Standardization (ISO) beta sources such as (147)Pm, (85)Kr, (90)Sr/(90)Y and (106)Ru/(106)Rh. The ratios are calculated at 5 and 70 µm depths along the central axis of the unit density ICRU-4-element tissue phantom as a function of air-cavity lengths of the extrapolation chamber l = 0.025-0.25 cm. The study shows that the BG values are independent of l and agree well with the ISO-reported values for the above sources. The overall variation in the SA values is ∼0.3% for all the investigated sources, when l is varied from 0.025 to 0.25 cm. As energy of the beta increases the SA stopping-power ratio for a given cavity length decreases. For example, SA values of (147)Pm are higher by ∼2% when compared with the corresponding values of (106)Ru/(106)Rh source. SA stopping-power ratios are higher than the BG stopping-power ratios and the degree of variation depends on type of source and the value of l. For example, the difference is up to 0.7 % at l = 0.025 cm for the (90)Sr/(90)Y source.

  18. Sources of alpha-, beta-, gamma-, delta- and epsilon-carotenes: a twentieth century review Fontes de alfa-, beta-, gama-, delta-, e epsilon-carotenos: uma revisão do século XX

    Directory of Open Access Journals (Sweden)

    José M. Barbosa-Filho


    Full Text Available Since humans cannot synthesize carotenoids, they depend upon the diet exclusively for the source of these micronutrients. It has claimed that they may alleviate chronic diseases such as cancers. The present communication constitutes a global review of the scientific literature on plants and others organisms that biosynthesize carotenoids, which include the series alpha-, beta-, gamma-, delta- and epsilon-carotenes. The results of the literature survey lists more than five hundred sources.Uma vez que os humanos não podem sintetizar carotenóides, dependem exclusivamente da dieta como fonte desses micronutrientes. Tem sido afirmado que eles podem aliviar doenças crônicas, tais como cânceres. O presente artigo constitui uma revisão global da literatura científica sobre plantas e outros organismos que biossintetizam carotenóides, que incluem as séries alfa-, beta-, gama-, delta-, e epsilon-carotenos. Os resultados das listas de pesquisa da literatura mostram mais de quinhentas fontes.

  19. Beta cell dynamics: beta cell replenishment, beta cell compensation and diabetes. (United States)

    Cerf, Marlon E


    Type 2 diabetes, characterized by persistent hyperglycemia, arises mostly from beta cell dysfunction and insulin resistance and remains a highly complex metabolic disease due to various stages in its pathogenesis. Glucose homeostasis is primarily regulated by insulin secretion from the beta cells in response to prevailing glycemia. Beta cell populations are dynamic as they respond to fluctuating insulin demand. Beta cell replenishment and death primarily regulate beta cell populations. Beta cells, pancreatic cells, and extra-pancreatic cells represent the three tiers for replenishing beta cells. In rodents, beta cell self-replenishment appears to be the dominant source for new beta cells supported by pancreatic cells (non-beta islet cells, acinar cells, and duct cells) and extra-pancreatic cells (liver, neural, and stem/progenitor cells). In humans, beta cell neogenesis from non-beta cells appears to be the dominant source of beta cell replenishment as limited beta cell self-replenishment occurs particularly in adulthood. Metabolic states of increased insulin demand trigger increased insulin synthesis and secretion from beta cells. Beta cells, therefore, adapt to support their physiology. Maintaining physiological beta cell populations is a strategy for targeting metabolic states of persistently increased insulin demand as in diabetes.

  20. Elaboration of Co-60 sources on gilding vyns, with beta efficiencies 80 % or better and its activity measure by the coincidences method; Elaboracion de fuentes de Co-60 sobre vyns dorado, con eficiencias beta del 80 % o mejor y su medida de actividad por el metodo de coincidencias

    Energy Technology Data Exchange (ETDEWEB)

    Cortes P, A.; Tejera R, A.; Becerril V, A.; Ortiz C, A


    The measuring technique of radioactive activity by the coincidences method 4 {pi} {beta}{sup -} {gamma} it requires of the elaboration of radioactive sources on thin supports in order to flows the biggest percentage of beta particles, those of the order of the 80 % or but. In this work a procedure for the elaboration of this type of sources, with gilding Vyns is reported. (Author)

  1. {beta}-decay data requirements for reactor decay heat calculations: study of the possible source of the gamma-ray discrepancy in reactor heat summation calculations

    Energy Technology Data Exchange (ETDEWEB)

    Algora, A.; Tain, J.L.; Perez-Cerdan, A.B.; Rubio, B.; Agramunt, J.; Caballero, L.; Nacher, E.; Jordan, D.; Molina, F. [Valencia Univ., IFIC (Spain); Algora, A.; Krasznahorkay, A.; Hunyadi, M.D.; Gulyas, J.; Vitez, A.; Csatlos, M.; Csige, L. [Institute of Nuclear Research, Debrecen (Hungary); Aysto, J.; Penttila, H.; Rinta-Antila, S.; Moore, I.; Eronen, T.; Jokinen, A.; Nieminen, A.; Hakala, J.; Karvonen, P.; Kankainen, A.; Hager, U.; Sonoda, T.; Saastamoinen, A.; Rissanen, J.; Kessler, T.; Weber, C.; Ronkainen, J.; Rahaman, S.; Elomaa, V. [Jyvaskyla Univ. (Finland); Burkard, K.; Huller, W. [GSI, Darmstadt (Germany); Batist, L. [PNPI, Gatchina (Russian Federation); Gelletly, W. [Surrey Univ., Guildford (United Kingdom); Yoshida, T. [Mushashi Institute of Technology (Japan); Nichols, A.L. [IAEA Nuclear Data Section, Vienna (Austria); Sonzogni, A. [National Nuclear Data Center, Brookhaven National Laboratory, Upton, NY (United States); Perajarvi, K. [STUK, Helsinki (Finland)


    The decay heat of fission products plays an important role in predictions of the heat up of nuclear fuel in reactors. The released energy is calculated as the summation of the activities of all fission products P(t) equals {sigma}(E{sub i}*{lambda}{sub i}*N{sub i}(t)), where E{sub i} is the decay energy of nuclide i (gamma and beta component), {lambda}{sub i} is the decay constant of nuclide i and N{sub i}(t) is the number of nuclide i at cooling time t. Even though the reproduction of the measured decay heat has improved in recent years, there is still a long standing discrepancy in the t about 1000 s cooling time for some fuels. A possible explanation to this improper description has been found in the work of Yoshida et al., where it has been shown that the incomplete knowledge of the {beta}-decay of some T{sub c} isotopes can be the source of the systematic discrepancy. We have recently measured the {beta}-decay process of some Tc isotopes using a total absorption spectrometer at the IGISOL facility in Jyvaskyla (Finland). The results of the measurements as well as the their consequences on summation calculations are discussed. (authors)

  2. Procedure to carry out leakage test in beta radiation sealed sources emitters of {sup 90}Sr/{sup 90}Y; Procedimiento para realizar prueba de fuga en fuentes selladas de radiacion beta emisoras de {sup 90}Sr/{sup 90}Y

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez R, J. T., E-mail: trinidad.alvarez@inin.gob.m [ININ, Departamento de Metrologia de Radiaciones Ionizantes, Laboratorio Secundario de Calibracion Dosimetrica, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)


    In the alpha-beta room of the Secondary Laboratory of Dosimetric Calibration of the Metrology Department of Ionizing Radiations ophthalmic applicators are calibrated in absorbed dose terms in water D{sub w}; these applicators, basically are emitter sealed sources of pure beta radiation of {sup 90}Sr / {sup 90}Y. Concretely, the laboratory quality system indicates to use the established procedure for the calibration of these sources, which establishes the requirement of to carry out a leakage test, before to calibrate the source. However, in the Laboratory leakage test certificates sent by specialized companies in radiological protection services have been received, in which are used gamma spectrometry equipment s for beta radiation leakage tests, since it is not reliable to detect pure beta radiation with a scintillating detector with NaI crystal, (because it could detect the braking radiation produced in the detector). Therefore the Laboratory has had to verify the results of the tests with a correct technique, with the purpose of determining the presence of sources with their altered integrity and radioactive material leakage. The objective of this work is to describe a technique for beta activity measurement - of the standard ISO 7503, part 1 (1988) - and its application with a detector Gm plane (type pankage) in the realization of leakage tests in emitter sources of pure beta radiation, inside the mark of quality assurance indicated by the report ICRU 76. (Author)

  3. Beta Thalassemia (United States)

    Beta thalassemia is found in people of Mediterranean, Middle Eastern, African, South Asian (Indian, Pakistani, etc.), Southeast Asian and Chinese descent. 1 Beta Thalassemia ßß Normal beta globin genes found on chromosomes ...

  4. Special Analysis for the Disposal of the Lawrence Livermore National Laboratory Low Activity Beta/Gamma Sources Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Shott, Gregory J. [National Security Technologies, LLC


    This special analysis (SA) evaluates whether the Lawrence Livermore National Laboratory (LLNL) Low Activity Beta/Gamma Sources waste stream (BCLALADOEOSRP, Revision 0) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The LLNL Low Activity Beta/Gamma Sources waste stream consists of sealed sources that are no longer needed. The LLNL Low Activity Beta/Gamma Sources waste stream required a special analysis because cobalt-60 (60Co), strontium-90 (90Sr), cesium-137 (137Cs), and radium-226 (226Ra) exceeded the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office [NNSA/NFO] 2015). The results indicate that all performance objectives can be met with disposal of the LLNL Low Activity Beta/Gamma Sources in a SLB trench. The LLNL Low Activity Beta/Gamma Sources waste stream is suitable for disposal by SLB at the Area 5 RWMS. However, the activity concentration of 226Ra listed on the waste profile sheet significantly exceeds the action level. Approval of the waste profile sheet could potentially allow the disposal of high activity 226Ra sources. To ensure that the generator does not include large 226Ra sources in this waste stream without additional evaluation, a control is need on the maximum 226Ra inventory. A limit based on the generator’s estimate of the total 226Ra inventory is recommended. The waste stream is recommended for approval with the control that the total 226Ra inventory disposed shall not exceed 5.5E10 Bq (1.5 Ci).

  5. Feasibility of photoelectron sources for testing the energy scale stablity of the KATRIN beta-ray spectrometer

    CERN Document Server

    Dragoun, O; Kaspar, J; Bonn, J; Kovalik, A; Otten, E W; Venos, D; Weinheimer, Ch


    Photoabsorption of nuclear gamma-rays in thin metallic convertors was examined with the aim to produce monoenergetic photoelectrons of kinetic energy around 18.6 keV and natural width of about 1 eV. Calculations were carried out for commercial photon sources of 241Am (1.1 GBq) and 119mSn (0.5 GBq) irradiating Co and Ti convertors. Photoelectrons ejected by 241Am gamma- and X-rays from Co convertors of various thickness were measured with two electrostatic spectrometers.

  6. Development of a low-energy and high-current pulsed neutral beam injector with a washer-gun plasma source for high-beta plasma experiments. (United States)

    Ii, Toru; Gi, Keii; Umezawa, Toshiyuki; Asai, Tomohiko; Inomoto, Michiaki; Ono, Yasushi


    We have developed a novel and economical neutral-beam injection system by employing a washer-gun plasma source. It provides a low-cost and maintenance-free ion beam, thus eliminating the need for the filaments and water-cooling systems employed conventionally. In our primary experiments, the washer gun produced a source plasma with an electron temperature of approximately 5 eV and an electron density of 5 × 10(17) m(-3), i.e., conditions suitable for ion-beam extraction. The dependence of the extracted beam current on the acceleration voltage is consistent with space-charge current limitation, because the observed current density is almost proportional to the 3/2 power of the acceleration voltage below approximately 8 kV. By optimizing plasma formation, we successfully achieved beam extraction of up to 40 A at 15 kV and a pulse length in excess of 0.25 ms. Its low-voltage and high-current pulsed-beam properties enable us to apply this high-power neutral beam injection into a high-beta compact torus plasma characterized by a low magnetic field.

  7. A mini X-ray generator as an alternative to a 90Sr/90Y beta source in luminescence dating

    DEFF Research Database (Denmark)

    Andersen, C.E.; Bøtter-Jensen, L.; Murray, A.S.


    We have carried out an investigation to test whether mini X-ray generators are a suitable alternative to radioactive sources in luminescence dating. The study has mainly been motivated by the need for high dose rates (similar to 1 Gy/s) to make dating of older samples using regeneration protocols...... more practical. Furthermore, X-ray generators are more suited for field work and work in countries where regulations restrict the use of radioactive sources. The system tested here (a 50 kV I mA Varian VF-50J tube with tungsten target and a matched Spellman high-voltage power supply) was found...... to provide: (i) excellent linearity between tube current (as set by the user on the control computer) and dose rate, (ii) a wide dynamic range: 2-30 mGy/s at 10 kV and 10-2000 mGy/s at 50 kV, (iii) short-term stability better than 0.2%, and (iv) a highly uniform irradiation of the sample area. Tests...

  8. $\\beta$-decay study of very neutron-rich Cd isotopes with a chemically selective laser ion source

    CERN Multimedia


    Following our test measurements of N=82-84 Cd isotopes with a specifically developed laser ion source (CERN/ISC 97-16, ISC/I 22), we now propose detailed spectroscopic studies of the decay of $^{130}$Cd to $\\,^{132}\\!$Cd, and at least the determination of some gross properties of the new N=85-86 nuclides $^{133}\\!$Cd and $\\,^{134}\\!$Cd. The main nuclear-structure objective of this experiment is the identification of the energies of the single-hole (SH) proton states in $^{131}$In. Nearly all of the other single-nucleon shell-model basis energies around doubly magic $^{132}$Sn are known by now, except those $\\pi$SH in Z=49 $\\,^{131}$In. Theoretical agreement on these values has not been achieved so far. Of particular interest is the depth of the $\\pi$f$_{5/3}$ hole and the p$_{3/2}$ - p$_{1/2}$ spin-orbit splitting. A second important goal is the determination of the position of the lowest-energy 1$^+\\,$ level in $^{130}$In predominantly populated in the Gamow-Teller (GT) decay of N=82 $^{130}\\!$Cd. Apart from...

  9. Status and Performance of New Silicon Stripixel Detector for the PHENIX Experiment at RHIC Beta Source, Cosmic-rays and Proton Beam at 120 GeV

    CERN Document Server

    Nouicer, Rachid


    We are constructing a Silicon Vertex Tracker detector (VTX) for the PHENIX experiment at RHIC. Our main motivation is to enable measurements of heavy flavor production (charm and beauty) in p+p, p+d and A+A collisions. Such data will illuminate the properties of the matter created in high-energy heavy-ion collisions. The measurements also will reveal the distribution of gluons in protons from p+p collisions. The VTX detector consists of four layers of barrel detectors and covers |eta|< 1.2, and almost a 2pi in azimuth. The inner two silicon barrels consist of silicon pixel sensors; their technology accords with that of the ALICE1LHCB sensor-readout hybrid. The outer two barrels are silicon stripixel detectors with a new "spiral" design, and a single-sided sensor with 2-dimensional (X, U) readout. In this paper, we describe the silicon stripixel detector and discuss its performance, including its response to electrons from a beta source (90Sr), muons from cosmic-rays, and a 120 GeV proton beam. The results ...

  10. Functional characterisation and cell specificity of BvSUT1, the transporter that loads sucrose into the phloem of sugar beet (Beta vulgaris L.) source leaves. (United States)

    Nieberl, P; Ehrl, C; Pommerrenig, B; Graus, D; Marten, I; Jung, B; Ludewig, F; Koch, W; Harms, K; Flügge, U-I; Neuhaus, H E; Hedrich, R; Sauer, N


    Sugar beet (Beta vulgaris L.) is one of the most important sugar-producing plants worldwide and provides about one third of the sugar consumed by humans. Here we report on molecular characterisation of the BvSUT1 gene and on the functional characterisation of the encoded transporter. In contrast to the recently identified tonoplast-localised sucrose transporter BvTST2.1 from sugar beet taproots, which evolved within the monosaccharide transporter (MST) superfamily, BvSUT1 represents a classical sucrose transporter and is a typical member of the disaccharide transporter (DST) superfamily. Transgenic Arabidopsis plants expressing the β-GLUCURONIDASE (GUS) reporter gene under control of the BvSUT1-promoter showed GUS histochemical staining of their phloem; an anti-BvSUT1-antiserum identified the BvSUT1 transporter specifically in phloem companion cells. After expression of BvSUT1 cDNA in bakers' yeasts (Saccharomyces cerevisiae) uptake characteristics of the BvSUT1 protein were studied. Moreover, the sugar beet transporter was characterised as a proton-coupled sucrose symporter in Xenopus laevis oocytes. Our findings indicate that BvSUT1 is the sucrose transporter that is responsible for loading of sucrose into the phloem of sugar beet source leaves delivering sucrose to the storage tissue in sugar beet taproot sinks.

  11. Extended-Spectrum beta (β)-Lactamases and Antibiogram in Enterobacteriaceae from Clinical and Drinking Water Sources from Bahir Dar City, Ethiopia (United States)

    Abera, Bayeh; Kibret, Mulugeta; Mulu, Wondemagegn


    Background The spread of Extended-Spectrum beta (β)-Lactamases (ESBL)-producing Enterobacteriaceae has become a serious global problem. ESBL-producing Enterobacteriaceae vary based on differences in antibiotic use, nature of patients and hospital settings. This study was aimed at determining ESBL and antibiogram in Enterobacteriaceae isolates from clinical and drinking water sources in Bahir Dar City, Northwest Ethiopia. Methods Enterobacteriaceae species were isolated from clinical materials and tap water using standard culturing procedures from September 2013 to March 2015. ESBL-producing-Enterobacteriaceae were detected using double-disk method by E-test Cefotaxim/cefotaxim+ clavulanic acid and Ceftazidime/ceftazidime+ clavulanic acid (BioMerieux SA, France) on Mueller Hinton agar (Oxoid, UK). Results Overall, 274 Enterobacteriaceae were isolated. Of these, 210 (44%) were from patients and 64 (17.1%) were from drinking water. The median age of the patients was 28 years. Urinary tract infection and blood stream infection accounted for 60% and 21.9% of Enterobacteriaceae isolates, respectively. Klebsiella pneumoniae was isolated from 9 (75%) of neonatal sepsis. The overall prevalence of ESBL-producing Enterobacteriaceae in clinical and drinking water samples were 57.6% and 9.4%, respectively. The predominant ESBL-producers were K. pneumoniae 34 (69.4%) and Escherichia coli 71 (58.2%). Statistically significant associations were noted between ESBL-producing and non- producing Enterobacteriaceae with regard to age of patients, infected body sites and patient settings (P = 0.001). ESBL-producing Enterobacteriaceae showed higher levels of resistance against chloramphenicol, ciprofloxacin and cotrimoxazole than non-ESBL producers (P = 0.001) Conclusions ESBL-producing Enterobacteriaceae coupled with high levels of other antimicrobials become a major concern for treatment of patients with invasive infections such as blood stream infections, neonatal sepsis and urinary

  12. Study of the background of the neutrinoless double {beta} decay with the detector NEMO 2: contribution arising from the radon diffusion and internal pollution of the source {sup 214}Bi have been estimated; Etude du bruit de fond de la double-desintegration {beta} sans emission de neutrino dans le detecteur NEMO 2: contribution du radon ambiant et mesure de la pollution interne de la source en {sup 214}Bi

    Energy Technology Data Exchange (ETDEWEB)

    Mauger, F.


    The NEMO experiment is designed to understand the nature of the neutrino by studying the double beta decay of Mo-100 which is related to the Majorana neutrino effective mass. In this kind of experiment a good understanding of the different sources of background is crucial as only few events are expected per year at the required level of sensitivity. In this thesis we present the main theoretical and experimental aspects of the measurement of the neutrinoless double beta decay of Mo-100 with the prototype detector NEMO2. The goal of this study is to obtain a realistic interpretation of the few events detected at high energy in the two-electron channel as a background to neutrinoless double beta decay. In particular, the contribution arising from Bi-214 has been investigated. These events have been selected and analysed by means of the beta-alpha decays of Bi-214 into Pb-210. The events are characterized by a delayed track in the wire chamber and the corresponding signal is rather clean. The study has demonstrated the diffusion of Rn-222 into the detector and its contribution to Bi-214 pollution has been estimated. A measurement of the Bi-214 internal contamination of the source has been made as well as an estimation of the Bi-214 deposit due to Rn-222. As a result of this study it appears that, under the conditions of the NEMO2 experiment, the Bi and Rn contributions are of the same order of magnitude as the background induced at high energy by two-neutrino double beta decay. In conclusion, the backgrounds of the neutrinoless double beta decay of Mo-100 are well understood in the NEMO2 experiment leading to an extrapolation for the NEMO3 experiment. (authors).

  13. Spectral parameters modulation and source localization of blink-related alpha and low-beta oscillations differentiate minimally conscious state from vegetative state/unresponsive wakefulness syndrome.

    Directory of Open Access Journals (Sweden)

    Luca Bonfiglio

    Full Text Available Recently, the cortical source of blink-related delta oscillations (delta BROs in resting healthy subjects has been localized in the posterior cingulate cortex/precuneus (PCC/PCu, one of the main core-hubs of the default-mode network. This has been interpreted as the electrophysiological signature of the automatic monitoring of the surrounding environment while subjects are immersed in self-reflecting mental activities. Although delta BROs were directly correlated to the degree of consciousness impairment in patients with disorders of consciousness, they failed to differentiate vegetative state/unresponsive wakefulness syndrome (VS/UWS from minimally conscious state (MCS. In the present study, we have extended the analysis of BROs to frequency bands other than delta in the attempt to find a biological marker that could support the differential diagnosis between VS/UWS and MCS. Four patients with VS/UWS, 5 patients with MCS, and 12 healthy matched controls (CTRL underwent standard 19-channels EEG recordings during resting conditions. Three-second-lasting EEG epochs centred on each blink instance were submitted to time-frequency analyses in order to extract the normalized Blink-Related Synchronization/Desynchronization (nBRS/BRD of three bands of interest (low-alpha, high-alpha and low-beta in the time-window of 50-550 ms after the blink-peak and to estimate the corresponding cortical sources of electrical activity. VS/UWS nBRS/BRD levels of all three bands were lower than those related to both CTRL and MCS, thus enabling the differential diagnosis between MCS and VS/UWS. Furthermore, MCS showed an intermediate signal intensity on PCC/PCu between CTRL and VS/UWS and a higher signal intensity on the left temporo-parieto-occipital junction and inferior occipito-temporal regions when compared to VS/UWS. This peculiar pattern of activation leads us to hypothesize that resting MCS patients have a bottom-up driven activation of the task positive network

  14. Spectral Parameters Modulation and Source Localization of Blink-Related Alpha and Low-Beta Oscillations Differentiate Minimally Conscious State from Vegetative State/Unresponsive Wakefulness Syndrome (United States)

    Bonfiglio, Luca; Piarulli, Andrea; Olcese, Umberto; Andre, Paolo; Arrighi, Pieranna; Frisoli, Antonio; Rossi, Bruno; Bergamasco, Massimo; Carboncini, Maria Chiara


    Recently, the cortical source of blink-related delta oscillations (delta BROs) in resting healthy subjects has been localized in the posterior cingulate cortex/precuneus (PCC/PCu), one of the main core-hubs of the default-mode network. This has been interpreted as the electrophysiological signature of the automatic monitoring of the surrounding environment while subjects are immersed in self-reflecting mental activities. Although delta BROs were directly correlated to the degree of consciousness impairment in patients with disorders of consciousness, they failed to differentiate vegetative state/unresponsive wakefulness syndrome (VS/UWS) from minimally conscious state (MCS). In the present study, we have extended the analysis of BROs to frequency bands other than delta in the attempt to find a biological marker that could support the differential diagnosis between VS/UWS and MCS. Four patients with VS/UWS, 5 patients with MCS, and 12 healthy matched controls (CTRL) underwent standard 19-channels EEG recordings during resting conditions. Three-second-lasting EEG epochs centred on each blink instance were submitted to time-frequency analyses in order to extract the normalized Blink-Related Synchronization/Desynchronization (nBRS/BRD) of three bands of interest (low-alpha, high-alpha and low-beta) in the time-window of 50–550 ms after the blink-peak and to estimate the corresponding cortical sources of electrical activity. VS/UWS nBRS/BRD levels of all three bands were lower than those related to both CTRL and MCS, thus enabling the differential diagnosis between MCS and VS/UWS. Furthermore, MCS showed an intermediate signal intensity on PCC/PCu between CTRL and VS/UWS and a higher signal intensity on the left temporo-parieto-occipital junction and inferior occipito-temporal regions when compared to VS/UWS. This peculiar pattern of activation leads us to hypothesize that resting MCS patients have a bottom-up driven activation of the task positive network and thus

  15. sources

    Directory of Open Access Journals (Sweden)

    Shu-Yin Chiang


    Full Text Available In this paper, we study the simplified models of the ATM (Asynchronous Transfer Mode multiplexer network with Bernoulli random traffic sources. Based on the model, the performance measures are analyzed by the different output service schemes.

  16. Sources



    SOURCES MANUSCRITES Archives nationales Rôles de taille 1768/71 Z1G-344/18 Aulnay Z1G-343a/02 Gennevilliers Z1G-340/01 Ivry Z1G-340/05 Orly Z1G-334c/09 Saint-Remy-lès-Chevreuse Z1G-344/18 Sevran Z1G-340/05 Thiais 1779/80 Z1G-391a/18 Aulnay Z1G-380/02 Gennevilliers Z1G-385/01 Ivry Z1G-387b/05 Orly Z1G-388a/09 Saint-Remy-lès-Chevreuse Z1G-391a/18 Sevran Z1G-387b/05 Thiais 1788/89 Z1G-451/18 Aulnay Z1G-452/21 Chennevières Z1G-443b/02 Gennevilliers Z1G-440a/01 Ivry Z1G-452/17 Noiseau Z1G-445b/05 ...

  17. Oxalate content of silver beet leaves (Beta vulgaris var. cicla) at different stages of maturation and the effect of cooking with different milk sources. (United States)

    Simpson, Thomas S; Savage, Geoffrey P; Sherlock, Robert; Vanhanen, Leo P


    The work presented here indicates that people who have a tendency to develop kidney stones should avoid consuming regrowth and developed silver beet (Beta vulgaris var. cicla) leaves. Soluble oxalate contents of leaves range from 58% of the total oxalate for the mature leaves up to 89% for the regrowth tissue, with regrowth tissue containing the highest levels of soluble oxalate at 7267+/-307 mg/100 g of dry matter (DM). Leaves cooked in milk contained significantly (pbeet, a low fat milk cooking medium with neutral pH should be utilized.

  18. Study of influence of plastic scintillators thicknesses to detect Beta particles and Gamma radiation by means of spectral analysis of {sup 90}Sr, {sup 90}Y and {sup 137}Cs sources

    Energy Technology Data Exchange (ETDEWEB)

    Cardenas, Jose Patricio Nahuel; Filho, Tufic Madi; Pereira, Maria da Conceicao Costa; Santos, Brianna B. dos; Correa, Eduardo de L.; Santos, Lucas Rodrigues dos; Lopes, Anderson Figueredo; Silva, Alexandre F.P. da; Santos, Diogo F. dos; Camilo, Douglas de S.; Purgato, Rafael T.; Aredes, Vitor O.G. [Nuclear and Energy Research Institute, IPEN-CNEN/SP, Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP, Av. Prof. Lineu Prestes 2242 Cid Universitaria CEP: 05508-000- Sao Paulo-SP (Brazil)


    The Nuclear and Energy Research Institute - IPEN, offers post-graduate programs, namely: Nuclear Technology - Applications (TNA), Nuclear Technology - Materials (TNM), Nuclear Technology - Reactors (TNR). The Institute programs mission is to form expert technicians, physicists and engineers with a strong knowledge in their discipline to work in the nuclear area. The course: 'Theoretical Fundamentals and Practices of the Instrumentation used in Nuclear Data Acquisition' covers the use of laboratory nuclear instrumentation and the accomplishment of experiments to obtain nuclear parameters. One of these experimental exercises is object of this work: 'Study of influence of plastic scintillators to detect Beta particles and Gamma radiation by means of spectral analysis of {sup 90}Sr, {sup 90}Y and {sup 137}Cs sources'. The use of scintillators plastic for the detection has the advantage of low cost, high mechanical strength, is not hygroscopic and can be manufactured in large volumes. This work aims to present the analysis of relative efficiency of detection of plastic scintillators of various thicknesses for beta particles and gamma radiation by the spectrum of {sup 137}Cs and {sup 90}Sr. Due to lack of resolution of the detectors plastic scintillators we worked with relative efficiency. The evaluation was done by reading deposited energy, using the software MAESTRO, for each detector thickness. For beta particles was observed an ideal thickness around 3 mm and the better photon efficiency was observed with increasing the thickness of the detector. The present experiment does not intend to establish a new technique for this subject: it solely aims student's practical exercises in nuclear properties of elements and detectors being part of the nuclear experimental course. (authors)

  19. Shielding for beta-gamma radiation. (United States)

    Fletcher, J J


    The build-up factor, B, for lead was expressed as a polynominal cubic function of the relaxation length, mu x, and incorporated in a "general beta-gamma shielding equation." A computer program was written to determine shielding thickness for polyenergetic beta-gamma sources without resorting to the conventional "add-one-HVL" method.

  20. Development of a multi-electrode extrapolation chamber as a prototype of a primary standard for the realization of the unit of the absorbed dose to water for beta brachytherapy sources

    CERN Document Server

    Bambynek, M


    The prototype of a primary standard has been developed, built and tested, which enables the realization of the unit of the absorbed dose to water for beta brachytherapy sources. In the course of the development of the prototype, the recommendations of the American Association of Physicists in Medicine (AAPM) Task Group 60 (TG60) and the Deutsche Gesellschaft fuer Medizinische Physik (DGMP) Arbeitskreis 18 (AK18) were taken into account. The prototype is based on a new multi-electrode extrapolation chamber (MEC) which meets, in particular, the requirements on high spatial resolution and small uncertainty. The central part of the MEC is a segmented collecting electrode which was manufactured in the clean room center of PTB by means of electron beam lithography on a wafer. A precise displacement device consisting of three piezoelectric macrotranslators has been incorporated to move the wafer collecting electrode against the entrance window. For adjustment of the wafer collecting electrode parallel to the entranc...

  1. The GERDA experiment on 0{nu}{beta}{beta} decay

    Energy Technology Data Exchange (ETDEWEB)

    Freund, Kai [Eberhard Karls Universitaet Tuebingen (Germany); Collaboration: GERDA-Collaboration


    The Gerda (Germanium Detector Array) collaboration searches for the neutrinoless double beta decay (0{nu}{beta}{beta}) of {sup 76}Ge. The existence of this decay would give rise to the assumption that the neutrino is a Majorana particle, i.e. its own antiparticle. A measured half-life could be used to determine the effective neutrino mass and hence resolve the neutrino mass hierarchy problem. Germanium diodes, isotopically enriched in {sup 76}Ge, are used as both source and detector. Due to the low rate of this decay (T{sub 1/2}>10{sup 25} y), the experimental background must be reduced to a level of 10{sup -2}counts/(kg y keV) or better in the region around Q{sub {beta}{beta}}. To minimize background from cosmogenically produced secondary particles, a low Z shielding is employed. Thus, the naked diodes are operated in a liquid argon cryostat, which is surrounded by a water tank acting as both passive shield and active muon Cherenkov veto. Gerda started the commissioning runs in 2010 and in November 2011, the first phase of data taking with enriched detectors has begun. In this talk, the first year of the experiment is summarized.

  2. Étude du détecteur de traces de l'expérience NEMO3. Simulation de la mesure de l'ultra-faible radioactivité en ${208}^TL$ des sources de l'expérience NEMO3 candidates à la double désintégration $\\beta$ sans émission de neutrino

    CERN Document Server

    Errahmane, K


    Étude du détecteur de traces de l'expérience NEMO3. Simulation de la mesure de l'ultra-faible radioactivité en ${208}^TL$ des sources de l'expérience NEMO3 candidates à la double désintégration $\\beta$ sans émission de neutrino

  3. Beta-carotene (United States)

    ... patches on the tongue and mouth called oral leukoplakia. Taking beta-carotene by mouth for up to 12 months seems to decrease symptoms of oral leukoplakia. Osteoarthritis. Beta-carotene taken by mouth may prevent ...

  4. Dosimetry of low-energy beta radiation

    Energy Technology Data Exchange (ETDEWEB)

    Borg, J.


    Useful techniques and procedures for determination of absorbed doses from exposure in a low-energy {beta} radiation field were studied and evaluated in this project. The four different techniques included were {beta} spectrometry, extrapolation chamber dosimetry, Monte Carlo (MC) calculations, and exoelectron dosimetry. As a typical low-energy {beta} radiation field a moderated spectrum from a {sup 14}C source (E{sub {beta}},{sub max} =156 keV) was chosen for the study. The measured response of a Si(Li) detector to photons (bremsstrahlung) showed fine agreement with the MC calculated photon response, whereas the difference between measured and MC calculated responses to electrons indicates an additional dead layer thickness of about 12 {mu}m in the Si(Li) detector. The depth-dose profiles measured with extrapolation chambers at two laboratories agreed very well, and it was confirmed that the fitting procedure previously reported for {sup 147}Pm depth-dose profiles is also suitable for {beta} radiation from {sup 14}C. An increasing difference between measured and MC calculated dose rates for increasing absorber thickness was found, which is explained by limitations of the EGS4 code for transport of very low-energy electrons (below 10-20 keV). Finally a study of the thermally stimulated exoelectron emission (TSEE) response of BeO thin film dosemeters to {beta} radiation for radiation fields with maximum {beta} energies ranging from 67 keV to 2.27 MeV is reported. For maximum {beta} energies below approximately 500 keV, a decrease in the response amounting to about 20% was observed. It is thus concluded that a {beta} dose higher than about 10 {mu}Gy can be measured with these dosemeters to within 0 to -20% independently of the {beta}energy for E{sub {beta}},{sub max} values down to 67 keV. (au) 12 tabs., 38 ills., 71 refs.

  5. Dosimetry of Low-Energy Beta Radiation

    DEFF Research Database (Denmark)

    Borg, Jette

    Useful techniques and procedures for derermination of absorbed doses from exposure in a low-energy beta radiation were studied and evaluated. The four techniques included were beta spectrometry, extrapolation chamber dosimetry, Monte Carlo (MC) calculations, and exoelectron dosimetry. As a typical...... low-energy beta radiation field a moderated spectrum from a carbon-14 source was used. The measured responce of a Si(Li) detector to photons (bremsstrahlung) showed fine agreemant with the MC calculated photon response, whereas the difference between measured and MC calculated response to electrons...

  6. 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......-looking. This paper introduces a radically different approach to estimating market betas. Using the tools in Bakshi and Madan (2000) and Bakshi, Kapadia and Madan (2003) we employ the information embedded in the prices of individual stock options and index options to compute our forward-looking market beta...

  7. Beta Beams for Precision Measurements of Neutrino Oscillation Parameters

    CERN Document Server

    Wildner, E; Hansen, C; De Melo Mendonca, T; Stora, T; Damjanovic, S; Payet, J; Chancé, A; Zorin, V; Izotov, I; Rasin, S; Sidorov, A; Skalyga, V; De Angelis, G; Prete, G; Cinausero, M; Kravchuk, V; Gramegna, F; Marchi, T; Collazuol, G; Mezzetto, M; Delbar, T; Loiselet, M; Keutgen, T; Mitrofanov, S; Burt, G; Dexter, A; Lamy, T; Latrasse, L; Marie-Jeanne, M; Sortais, P; Thuillier, T; Debray, F; Trophime, C; Hass, M; Hirsh, T; Berkovits, D; Stahl, A; Vardaci, E; Di Nitto, A; Brondi, A; La Rana, G; Moro, R; De Rosa, G; Palladino, V


    Neutrino oscillations have implications for the Standard Model of particle physics. The CERN Beta Beam has outstanding capabilities to contribute to precision measurements of the parameters governing neutrino oscillations. The FP7 collaboration EUROnu (2008-2012) is a design study that will review three facilities (Super-Beams, Beta Beams and Neutrino Factories) and perform a cost assessment that, coupled with the physics performance, will give means to the European research authorities to make decisions on future European neutrino oscillation facilities. ”Beta Beams” produce collimated pure electron (anti)neutrinos by accelerating beta active ions to high energies and having them decay in a storage ring. Using existing machines and infrastructure is an advantage for the cost evaluation; however, this choice is also constraining the Beta Beams. Recent work to make the Beta Beam facility a solid option will be described: production of Beta Beam isotopes, the 60 GHz pulsed ECR source development, integratio...

  8. Betting against Beta

    DEFF Research Database (Denmark)

    Frazzini, Andrea; Heje Pedersen, Lasse


    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......, the return of the BAB factor is low. (4) Increased funding liquidity risk compresses betas toward one. (5) More constrained investors hold riskier assets....... for US 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...

  9. Betting Against Beta

    DEFF Research Database (Denmark)

    Frazzini, Andrea; Heje Pedersen, Lasse

    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) Since constrained investors bid up high-beta assets, high beta is associated with low alpha, as we find empirically for U...... of the BAB factor is low; (4) Increased funding liquidity risk compresses betas toward one; (5) More constrained investors hold riskier assets........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...

  10. Imperfect World of $\\beta\\beta$-decay Nuclear Data Sets

    CERN Document Server

    Pritychenko, B


    The precision of double-beta ($\\beta\\beta$) 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 $\\beta\\beta$-decay T$_{1/2}^{2\

  11. Negative Beta Encoder

    CERN Document Server

    Kohda, Tohru; Aihara, Kazuyuki


    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. Double beta decay experiments

    CERN Document Server

    Barabash, A S


    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.

  13. Genetics Home Reference: beta thalassemia (United States)

    ... Understand Genetics Home Health Conditions beta thalassemia beta thalassemia Enable Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Beta thalassemia is a blood disorder that reduces the production ...

  14. Rapid synthesis of beta zeolites (United States)

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


    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.

  15. Beta adrenergic receptors in human cavernous tissue

    Energy Technology Data Exchange (ETDEWEB)

    Dhabuwala, C.B.; Ramakrishna, C.V.; Anderson, G.F.


    Beta adrenergic receptor binding was performed with /sup 125/I iodocyanopindolol on human cavernous tissue membrane fractions from normal tissue and transsexual procedures obtained postoperatively, as well as from postmortem sources. Isotherm binding studies on normal fresh tissues indicated that the receptor density was 9.1 fmoles/mg. with a KD of 23 pM. Tissue stored at room temperature for 4 to 6 hours, then at 4C in saline solution for 19 to 20 hours before freezing showed no significant changes in receptor density or affinity, and provided evidence for the stability of postmortem tissue obtained within the same time period. Beta receptor density of 2 cavernous preparations from transsexual procedures was not significantly different from normal control tissues, and showed that high concentrations of estrogen received by these patients had no effect on beta adrenergic receptor density. Displacement of /sup 125/iodocyanopindolol by 5 beta adrenergic agents demonstrated that 1-propranolol had the greatest affinity followed by ICI 118,551, zinterol, metoprolol and practolol. When the results of these displacement studies were subjected to Scatfit, non- linear regression line analysis, a single binding site was described. Based on the relative potency of the selective beta adrenergic agents it appears that these receptors were of the beta 2 subtype.

  16. Purification and properties of beta-galactosidase from Aspergillus nidulans. (United States)

    Díaz, M; Pedregosa, A M; de Lucas, J R; Torralba, S; Monistrol, I F; Laborda, F


    Beta-Galactosidase from mycelial extract of Aspergillus nidulans has been purified by substrate affinity chromatography and used to obtain anti-beta-galactosidase polyclonal antibodies. A. nidulans growing in lactose as carbon source synthesizes one active form of beta-galactosidase which seems to be a multimeric enzyme of 450 kDa composed of monomers with 120 and 97 kDa. Although the enzyme was not released to the culture medium, some enzymatic activity was detected in a cell-wall extract, thus suggesting that it can be an extracellular enzyme. Beta-Galactosidase of A. nidulans is a very unstable enzyme with an optimum pH value of 7.5 and an optimum temperature of 30 degrees C. It was only active against beta-galactoside substrates like lactose and p-nitrophenyl-beta-D-galactoside (PNPG).

  17. Conversion of rice husk ash to zeolite beta. (United States)

    Prasetyoko, Didik; Ramli, Zainab; Endud, Salasiah; Hamdan, Halimaton; Sulikowski, Bogdan


    White rice husk ash (RHA), an agriculture waste containing crystalline tridymite and alpha-cristobalite, was used as a silica source for zeolite Beta synthesis. The crystallization of zeolite Beta from RHA at 150 degrees C in the presence of tetraethylammonium hydroxide was monitored by XRD, FTIR and (29)Si MAS NMR techniques. It was found that zeolite Beta started to form after 12h and the complete crystallization of zeolite Beta phase was achieved after 2d. XRD, (29)Si MAS NMR and solid yield studies indicate that the transformation mechanism of silica present in RHA to zeolite Beta involves dissolution of the ash, formation of an amorphous aluminosilicate after 6h of crystallization, followed by dissolution in the mother liquor and final transformation to pure zeolite Beta crystals.

  18. Neutrinoless double beta decay

    Indian Academy of Sciences (India)

    Kai Zuber


    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.

  19. Population screening for beta-thalassaemia. (United States)

    Flatz, S D; Flatz, G


    The graphic recording of time to 50% haemolysis in a glycerine-saline solution is a simple, reproducible method of determining erythrocyte osmotic fragility. Studies on a normal population yielded an upper limit of normal of 90 s. In 250 healthy males from Northern Thailand all 19 with beta-thalassaemia minor had abnormal osmotic indices, and the value of the test was confirmed in beta-thalassaemia heterozygotes in Europe. Of 23 patients with iron deficiency 18 had abnormal osmotic indices. However, this is not thought likely to be a significant source of false positives in the screening of populations at risk of haemoglobinopathies but in whom iron deficiency is rare.

  20. Detecting Double Beta Decays Using Nuclear Emulsions

    CERN Document Server

    Dracos, Marcos


    Neutrino nature and absolute mass scale are major questions in particle physics which cannot be addressed by the present neutrino oscillation program. To answer these two questions, several neutrinoless double beta decay experiments are underway or planed for the near future. These experiments, mainly use bolometric techniques or gaseous counters coupled with scintillator detectors. The energy resolution is better in bolometric experiments but experiments coupling tracking with calorimetry have the advantage of observing the two electron tracks and remove many background sources. Here, we present a proposal of using nuclear emulsions to observe double beta decays. This technique has the advantage of precise tracking and vertexing even for low energy electrons.

  1. Beta-decay of {sup 56}Cu

    Energy Technology Data Exchange (ETDEWEB)

    Ramdhane, M.; Baumann, P.; Knipper, A.; Walter, G. [Institute de Recherches Subatomiques, 67 - Strasbourg (France); Janas, Z.; Plochocki, A. [Warsaw Univ. (Poland). Inst. of Experimental Physics; Aeystoe, J.; Dendooven, P.; Jokinen, A.; Oinonen, M.; Pentilae, H. [Jyvaeskylae Univ. (Finland); Liu, W.; Grawe, H.; Hu, Z.; Kirchner, R.; Klepper, O.; Roeckl, E. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Gorska, M. [Warsaw Univ. (Poland). Inst. of Experimental Physics]|[Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Fujita, Y. [Osaka Univ. (Japan); Brown, B.A. [Michigan State Univ., East Lansing, MI (United States)


    By measuring positrons and {beta}-delayed {gamma}-rays emitted from mass-separated sources, the decay of {sup 56}Cu(4{sup +},T{sub z}=-1,T=1) to states in the doubly-magic nucleus {sup 56}Ni was studied for the first time. The half-life of {sup 56}Cu was measured to be 78(15) ms, and four {beta}-delayed {gamma}-rays were assigned to its decay. The resulting experimental data on Fermi and Gamow-Teller strength are compared with shell-model predictions. (orig.)

  2. Alpha and Beta Determinations

    CERN Document Server

    Dunietz, Isard


    Because the Bd -> J/psi Ks asymmetry determines only sin(2 beta), a discrete ambiguity in the true value of beta remains. This note reviews how the ambiguity can be removed. Extractions of the CKM angle alpha are discussed next. Some of the methods require very large data samples and will not be feasible in the near future. In the near future, semi-inclusive CP-violating searches could be undertaken, which are reviewed last.

  3. A Novel Dimeric Inhibitor Targeting Beta2GPI in Beta2GPI/Antibody Complexes Implicated in Antiphospholipid Syndrome

    Energy Technology Data Exchange (ETDEWEB)

    A Kolyada; C Lee; A De Biasio; N Beglova


    {beta}2GPI is a major antigen for autoantibodies associated with antiphospholipid syndrome (APS), an autoimmune disease characterized by thrombosis and recurrent pregnancy loss. Only the dimeric form of {beta}2GPI generated by anti-{beta}2GPI antibodies is pathologically important, in contrast to monomeric {beta}2GPI which is abundant in plasma. We created a dimeric inhibitor, A1-A1, to selectively target {beta}2GPI in {beta}2GPI/antibody complexes. To make this inhibitor, we isolated the first ligand-binding module from ApoER2 (A1) and connected two A1 modules with a flexible linker. A1-A1 interferes with two pathologically important interactions in APS, the binding of {beta}2GPI/antibody complexes with anionic phospholipids and ApoER2. We compared the efficiency of A1-A1 to monomeric A1 for inhibition of the binding of {beta}2GPI/antibody complexes to anionic phospholipids. We tested the inhibition of {beta}2GPI present in human serum, {beta}2GPI purified from human plasma and the individual domain V of {beta}2GPI. We demonstrated that when {beta}2GPI/antibody complexes are formed, A1-A1 is much more effective than A1 in inhibition of the binding of {beta}2GPI to cardiolipin, regardless of the source of {beta}2GPI. Similarly, A1-A1 strongly inhibits the binding of dimerized domain V of {beta}2GPI to cardiolipin compared to the monomeric A1 inhibitor. In the absence of anti-{beta}2GPI antibodies, both A1-A1 and A1 only weakly inhibit the binding of pathologically inactive monomeric {beta}2GPI to cardiolipin. Our results suggest that the approach of using a dimeric inhibitor to block {beta}2GPI in the pathological multivalent {beta}2GPI/antibody complexes holds significant promise. The novel inhibitor A1-A1 may be a starting point in the development of an effective therapeutic for antiphospholipid syndrome.

  4. {beta} - amyloid imaging probes

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Jae Min [Seoul National University College of Medicine, Seoul (Korea, Republic of)


    Imaging distribution of {beta} - amyloid plaques in Alzheimer's disease is very important for early and accurate diagnosis. Early trial of the {beta} -amyloid plaques includes using radiolabeled peptides which can be only applied for peripheral {beta} - amyloid plaques due to limited penetration through the blood brain barrier (BBB). Congo red or Chrysamine G derivatives were labeled with Tc-99m for imaging {beta} - amyloid plaques of Alzheimer patient's brain without success due to problem with BBB penetration. Thioflavin T derivatives gave breakthrough for {beta} - amyloid imaging in vivo, and a benzothiazole derivative [C-11]6-OH-BTA-1 brought a great success. Many other benzothiazole, benzoxazole, benzofuran, imidazopyridine, and styrylbenzene derivatives have been labeled with F-18 and I-123 to improve the imaging quality. However, [C-11]6-OH-BTA-1 still remains as the best. However, short half-life of C-11 is a limitation of wide distribution of this agent. So, it is still required to develop an Tc-99m, F-18 or I-123 labeled agent for {beta} - amyloid imaging agent.

  5. New precision measurements of free neutron beta decay with cold neutrons

    CERN Document Server

    Baeßler, S; Penttilä, S; Počanić, D


    Precision measurements in free neutron beta decay serve to determine the coupling constants of beta decay, and offer several stringent tests of the Standard Model. This paper describes the free neutron beta decay program planned for the Fundamental Physics Beamline at the Spallation Neutron Source at Oak Ridge National Laboratory, and puts it into the context of other recent and planned measurements of neutron beta decay observables.

  6. Estimating beta-mixing coefficients via histograms

    CERN Document Server

    McDonald, Daniel J; Schervish, Mark


    The literature on statistical learning for time series often assumes asymptotic independence or "mixing" of data sources. Beta-mixing has long been important in establishing the central limit theorem and invariance principle for stochastic processes; recent work has identified it as crucial to extending results from empirical processes and statistical learning theory to dependent data, with quantitative risk bounds involving the actual beta coefficients. There is, however, presently no way to actually estimate those coefficients from data; while general functional forms are known for some common classes of processes (Markov processes, ARMA models, etc.), specific coefficients are generally beyond calculation. We present an l1-risk consistent estimator for the beta-mixing coefficients, based on a single stationary sample path. Since mixing coefficients involve infinite-order dependence, we use an order-d Markov approximation. We prove high-probability concentration results for the Markov approximation and show...

  7. Response of ionization chamber based pocket dosimeter to beta radiation. (United States)

    Kumar, Munish; Gupta, Anil; Pradhan, S M; Bakshi, A K; Chougaonkar, M P; Babu, D A R


    Quantitative estimate of the response of ionization chamber based pocket dosimeters (DRDs) to various beta sources was performed. It has been established that the ionization chamber based pocket dosimeters do not respond to beta particles having energy (Emax)1 MeV, the DRDs exhibit measureable response and the values are ~8%, ~14% and ~27% per mSv for natural uranium, (90)Sr/(90)Y and (106)Ru/(106)Rh beta sources respectively. As the energy of the beta particles increases, the response also increases. The response of DRDs to beta particles having energy>1 MeV arises due to the fact that the thickness of the chamber walls is less than the maximum range of beta particles. This may also be one of the reasons for disparity between doses measured with passive/legal dosimeters (TLDs) and DRDs in those situations in which radiation workers are exposed to mixed field of gamma photons and beta particles especially at uranium processing plants, nuclear (power and research) reactors, waste management facilities and fuel reprocessing plants etc. The paper provides the reason (technical) for disparity between the doses recorded by TLDs and DRDs in mixed field of photons and beta particles.

  8. Boosted beta regression.

    Directory of Open Access Journals (Sweden)

    Matthias Schmid

    Full Text Available Regression analysis with a bounded outcome is a common problem in applied statistics. Typical examples include regression models for percentage outcomes and the analysis of ratings that are measured on a bounded scale. In this paper, we consider beta regression, which is a generalization of logit models to situations where the response is continuous on the interval (0,1. Consequently, beta regression is a convenient tool for analyzing percentage responses. The classical approach to fit a beta regression model is to use maximum likelihood estimation with subsequent AIC-based variable selection. As an alternative to this established - yet unstable - approach, we propose a new estimation technique called boosted beta regression. With boosted beta regression estimation and variable selection can be carried out simultaneously in a highly efficient way. Additionally, both the mean and the variance of a percentage response can be modeled using flexible nonlinear covariate effects. As a consequence, the new method accounts for common problems such as overdispersion and non-binomial variance structures.

  9. Beta and Gamma Gradients

    DEFF Research Database (Denmark)

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


    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...

  10. Applied Beta Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Rich, B.L.


    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.

  11. Beta Thalassemia (For Parents) (United States)

    ... had their spleens removed. Slower growth rates. The anemia resulting from beta thalassemia can cause children to grow more slowly and also can lead ... boost production of new red blood cells. Some children with moderate anemia may require an occasional blood transfusion , particularly after ...

  12. Trichoderma .beta.-glucosidase (United States)

    Dunn-Coleman, Nigel; Goedegebuur, Frits; Ward, Michael; Yao, Jian


    The present invention provides a novel .beta.-glucosidase nucleic acid sequence, designated bgl3, and the corresponding BGL3 amino acid sequence. The invention also provides expression vectors and host cells comprising a nucleic acid sequence encoding BGL3, recombinant BGL3 proteins and methods for producing the same.

  13. 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...

  14. Eukaryotic beta-alanine synthases are functionally related but have a high degree of structural diversity

    DEFF Research Database (Denmark)

    Gojkovic, Zoran; Sandrini, Michael; Piskur, Jure


    beta -Alanine synthase (EC, which catalyzes the final step of pyrimidine catabolism, has only been characterized in mammals. A Saccharomyces kluyveri pyd3 mutant that is unable to grow on N-carbamy-beta -alanine as the sole nitrogen source and exhibits diminished beta -alanine synthase...... no pyrimidine catabolic pathway, it enabled growth on N-carbamyl- beta -alanine as the sole nitrogen source. The D. discoideum and D. melanogaster PYD3 gene products are similar to mammalian beta -alanine synthases. In contrast, the S. kluyveri protein is quite different from these and more similar to bacterial...... N- carbamyl amidohydrolases. All three beta -alanine synthases are to some degree related to various aspartate transcarbamylases, which catalyze the second step of the de novo pyrimidine biosynthetic pathway. PYD3 expression in yeast seems to be inducible by dihydrouracil and N-carbamyl-beta...

  15. Beta-decay of Cu-56

    NARCIS (Netherlands)

    Ramdhane, M; Baumann, P; Knipper, A; Walter, G; Janas, Z; Plochocki, A; Aysto, J; Dendooven, P; Jokinen, A; Oinonen, M; Pentila, H; Liu, W; Gorska, M; Grawe, H; Hu, Z; Kirchner, R; Klepper, O; Roeckl, E; Fujita, Y; Brown, BA


    By measuring positrons and P-delayed gamma-rays emitted from mass-separated sources, the decay of Cu-56 (4(+),T-z = -1,T = 1) to states in the doubly-magic nucleus Ni-56 was Studied for the first time. The half-life of Cu-56 was measured to be 78(15) ms, and four beta-delayed gamma-rays were assigne

  16. Precision mass measurements utilizing beta endpoints

    CERN Document Server

    Moltz, D M; Kern, B D; Noma, H; Ritchie, B G; Toth, K S


    A technique for precise determination of beta endpoints with an intrinsic germanium detector has been developed. The energy calibration is derived from gamma -ray photopeak measurements. This analysis procedure has been checked with a /sup 27/Si source produced in a (p, n) reaction on a /sup 27/Al target and subsequently applied to mass separated samples of /sup 76/Rb, /sup 77/Rb and /sup 78/Rb. Results indicate errors <50 keV are obtainable. (29 refs).

  17. TGF-beta and osteoarthritis.

    NARCIS (Netherlands)

    Blaney Davidson, E.N.; Kraan, P.M. van der; Berg, W.B. van den


    OBJECTIVE: Cartilage damage is a major problem in osteoarthritis (OA). Growth factors like transforming growth factor-beta (TGF-beta) have great potential in cartilage repair. In this review, we will focus on the potential therapeutic intervention in OA with TGF-beta, application of the growth facto

  18. High energy beta rays and vectors of Bilharzia and Fasciola

    Energy Technology Data Exchange (ETDEWEB)

    Fletcher, J.J.; Akpa, T.C.; Dim, L.A.; Ogunsusi, R.


    Preliminary investigations of the effects of high energy beta rays on Lymnea natalensis, the snail vector of Schistosoma haematobium have been conducted. Results show that in both stream and tap water, about 70% of the snails die when irradiated for up to 18 hours using a 15m Ci Sr-90 beta source. The rest of the snails die without further irradiation in 24 hours. It may then be possible to control the vectors of Bilharzia and Fasciola by using both the direct and indirect effects of high energy betas.

  19. Transforming growth factor-beta: possible roles in carcinogenesis.


    Roberts, A B; Thompson, N L; Heine, U.; Flanders, C.; Sporn, M B


    TGF-beta is the prototype of a large family of multifunctional regulatory proteins. The principal sources of the peptide, platelets and bone, suggest that it plays a role in healing and remodeling processes. In vitro, TGF-beta is chemotactic for monocytes and fibroblasts and can greatly enhance accumulation of extracellular matrix components by fibroblasts. Its ability to stimulate the formation of granulation tissue locally and the demonstration of specific time- and tissue-dependent express...


    Mangini, Colby D; Hamby, David M


    Scaling of dose-point kernel (DPK) values for beta particles transmitted by high-Z sources will overestimate dose at shallow depths while underestimating dose at greater depths due to spectral hardening. A new model has been developed based on a determination of the amount of monoenergetic electron absorption that occurs in a given source thickness through the use of EGSnrc (Electron Gamma Shower) Monte Carlo simulations. Integration over a particular beta spectrum provides the beta-particle DPK following self-absorption as a function of source thickness and radial depth in water, thereby accounting for spectral hardening that may occur in higher-Z materials. Beta spectra of varying spectral shapes and endpoint energies were used to test the model for select source materials with 7.42 ≤ Z ≤ 94. The results demonstrate that significant improvements can be made to DPK-based dosimetry models when dealing with high-Z volumetric sources. This new scaling model is currently being used to improve the accuracy of the beta-dosimetry calculations in VARSKIN 5.

  1. Differential regulation of chemoattractant-stimulated beta 2, beta 3, and beta 7 integrin activity. (United States)

    Sadhu, C; Masinovsky, B; Staunton, D E


    Leukocyte adhesion to endothelium and extravasation are dynamic processes that require activation of integrins. Chemoattractants such as IL-8 and FMLP are potent activators of leukocyte integrins. To compare the chemoattractant-stimulated activation of three integrins, alpha 4 beta 7, alpha L beta 2, and alpha V beta 3, in the same cellular context, we expressed an IL-8 receptor (IL-8RA) and FMLP receptor (FPR) in the lymphoid cell line JY. Chemoattractants induced a rapid increase in alpha L beta 2- and alpha V beta 3-dependent JY adhesion within 5 min, and it was sustained for 30 min. In contrast, stimulation of alpha 4 beta 7-dependent adhesion was transient, returning to basal levels by 30 min. The activation profiles of the integrins were similar regardless of whether IL-8 or FMLP was used for induction. We also demonstrate that alpha 4 beta 7-dependent adhesion was uniquely responsive to the F actin-disrupting agent cytochalasin D and the protein kinase C (PKC) inhibitor chelerythrin. While alpha V beta 3- and alpha L beta 2-mediated cell adhesion was significantly reduced by cytochalasin D, alpha 4 beta 7-mediated adhesion was enhanced. Chelerythrin inhibited both the IL-8 and PMA activation of alpha L beta 2 and alpha V beta 3. In contrast, inducible alpha 4 beta 7 activity was unaffected, and basal activity was increased. These findings demonstrate that the mechanism of alpha 4 beta 7 regulation by chemoattractants is different from that of alpha L beta 2 and alpha V beta 3 and that it appears to involve distinct cytoskeletal and PKC dependencies. In addition, PKC activity may be a positive or negative regulator of integrin-dependent adhesion.

  2. Beta-thalassemia

    Directory of Open Access Journals (Sweden)

    Origa Raffaella


    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

  3. Beta-thalassemia. (United States)

    Galanello, Renzo; Origa, Raffaella


    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, deletions in the beta

  4. Beta and muon decays

    Energy Technology Data Exchange (ETDEWEB)

    Galindo, A.; Pascual, P.


    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)

  5. Realized Beta GARCH

    DEFF Research Database (Denmark)

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


    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 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 the beta. We apply the model to a large set of assets and find the conditional betas to be far more variable than usually found with rolling-window regressions based exclusively on daily returns. In the empirical part of the paper, we examine the cross-sectional as well as the time variation...

  6. Coroutine Sequencing in BETA

    DEFF Research Database (Denmark)

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

    In object-oriented programming, a program execution is viewed as a physical model of some real or imaginary part of the world. A language supporting object-oriented programming must therefore contain comprehensive facilities for modeling phenomena and concepts form the application domain. Many ap...... applications in the real world consist of objects carrying out sequential processes. Coroutines may be used for modeling objects that alternate between a number of sequential processes. The authors describe coroutines in BETA...

  7. Magic Baseline Beta Beam

    CERN Document Server

    Agarwalla, Sanjib Kumar; Raychaudhuri, Amitava


    We study the physics reach of an experiment where neutrinos produced in a beta-beam facility at CERN are observed in a large magnetized iron calorimeter (ICAL) at the India-based Neutrino Observatory (INO). The CERN-INO distance is close to the so-called "magic" baseline which helps evade some of the parameter degeneracies and allows for a better measurement of the neutrino mass hierarchy and $\\theta_{13}$.

  8. Beta cell adaptation in pregnancy

    DEFF Research Database (Denmark)

    Nielsen, Jens Høiriis


    Pregnancy is associated with a compensatory increase in beta cell mass. It is well established that somatolactogenic hormones contribute to the expansion both indirectly by their insulin antagonistic effects and directly by their mitogenic effects on the beta cells via receptors for prolactin...... and growth hormone expressed in rodent beta cells. However, the beta cell expansion in human pregnancy seems to occur by neogenesis of beta cells from putative progenitor cells rather than by proliferation of existing beta cells. Claes Hellerström has pioneered the research on beta cell growth for decades......, but the mechanisms involved are still not clarified. In this review the information obtained in previous studies is recapitulated together with some of the current attempts to resolve the controversy in the field: identification of the putative progenitor cells, identification of the factors involved...

  9. Regulation of beta cell replication

    DEFF Research Database (Denmark)

    Lee, Ying C; Nielsen, Jens Høiriis


    Beta cell mass, at any given time, is governed by cell differentiation, neogenesis, increased or decreased cell size (cell hypertrophy or atrophy), cell death (apoptosis), and beta cell proliferation. Nutrients, hormones and growth factors coupled with their signalling intermediates have been...... suggested to play a role in beta cell mass regulation. In addition, genetic mouse model studies have indicated that cyclins and cyclin-dependent kinases that determine cell cycle progression are involved in beta cell replication, and more recently, menin in association with cyclin-dependent kinase...... inhibitors has been demonstrated to be important in beta cell growth. In this review, we consider and highlight some aspects of cell cycle regulation in relation to beta cell replication. The role of cell cycle regulation in beta cell replication is mostly from studies in rodent models, but whether...

  10. Wind-Forced Baroclinic Beta-Plumes (United States)

    Belmadani, A.; Maximenko, N. A.; Melnichenko, O.; Schneider, N.; Di Lorenzo, E.


    A planetary beta-plume is a classical example of oceanic circulation induced by a localized vorticity source or sink that allows an analytical description in simplistic cases. Its barotropic structure is a zonally-elongated, gyre-like cell governed by the Sverdrup circulation on the beta-plane. The dominant zonal currents, found west of the source/sink, are often referred to as zonal jets. This simple picture describes the depth-integrated flow. Previous studies have investigated beta-plumes in a reduced-gravity framework or using other simple models with a small number of vertical layers, thereby lacking representation of the vertical structure. In addition, most previous studies use a purely linear regime without considering the role of eddies. However, these jets are often associated with strong lateral shear that makes them unstable under increased forcing. The circulation in such a nonlinear regime may involve eddy-mean flow interactions, which modify the time-averaged circulation. Here, the baroclinic structures of linear and nonlinear wind-forced beta-plumes are studied using a continuously-stratified, primitive equation, eddy-permitting ocean model (ROMS). The model is configured in an idealized rectangular domain for the subtropical ocean with a flat bottom. The surface wind forcing is a steady anticyclonic Gaussian wind vortex, which provides a localized vorticity source in the center of the domain. The associated wind stress curl and Ekman pumping comprise downwelling in the vortex center surrounded by a ring of weaker upwelling. Under weak forcing, the simulated steady-state circulation corresponds well with a theoretical linear beta-plume. While its depth-integrated transport exhibits a set of zonal jets, consistent with Sverdrup theory, the baroclinic structure of the plume is remarkably complex. Relatively fast westward decay of the surface currents occurs simultaneously with the deepening of the lower boundary of the plume. This deepening suggests

  11. Effect of mixing rate on Beta-carotene production and extraction by dunaliella salina in two-phase bioreactors

    NARCIS (Netherlands)

    Hejazi, M.; Andrysiewicz, E.; Tramper, J.; Wijffels, R.H.


    beta-Carotene has many applications in the food, cosmetic, and pharmaceutical industries; Dunaliella salina is currently the main source for natural beta-carotene. We have investigated the effect of mixing rate and whether it leads to the facilitated release of beta-carotene from the cells of Dunali

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

    CERN Multimedia

    Conti, G


    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.

  13. Generation of Transplantable Beta Cells for Patient-Specific Cell Therapy

    Directory of Open Access Journals (Sweden)

    Xiaojie Wang


    Full Text Available Islet cell transplantation offers a potential cure for type 1 diabetes, but it is challenged by insufficient donor tissue and side effects of current immunosuppressive drugs. Therefore, alternative sources of insulin-producing cells and isletfriendly immunosuppression are required to increase the efficiency and safety of this procedure. Beta cells can be transdifferentiated from precursors or another heterologous (non-beta-cell source. Recent advances in beta cell regeneration from somatic cells such as fibroblasts could circumvent the usage of immunosuppressive drugs. Therefore, generation of patient-specific beta cells provides the potential of an evolutionary treatment for patients with diabetes.

  14. Current and future searches for neutrinoless double beta decay (United States)

    Dolinski, Michelle J.


    With the discovery of neutrino oscillations and neutrino mass, it has become a pressing question whether neutrinos have distinct antiparticle states. The most practical experimental approach to answering this question is the search for neutrinoless double beta decay, a version of a rare nuclear process that would violate lepton number conservation. The observation of neutrinoless double beta decay would prove that neutrinos are their own antiparticles. Neutrinoless double beta decay experiments deploy large source masses consisting of a select few (usually enriched) isotopes of interest. Detectors must achieve extremely low levels of radioactive background to detect this rare decay. I will report on recent searches for neutrinoless double beta decay and discuss the technical challenges that the next generation of experiments will overcome.

  15. Simultaneous beta and gamma spectroscopy (United States)

    Farsoni, Abdollah T.; Hamby, David M.


    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.

  16. Beta section Beta: biogeographical patterns of variation and taxonomy.

    NARCIS (Netherlands)

    Letschert, J.P.W.


    In Chapter 1 an account is given of the historical subdivision of the genus Beta and its sections, and the relations of the sections are discussed. Emphasis is given to the taxonomic treatment of wild section Beta by various authors. The Linnaean names B. vulgaris L. and B. maritima L. are lectotypi

  17. The replication of beta cells in normal physiology, in disease and for therapy. (United States)

    Butler, Peter C; Meier, Juris J; Butler, Alexandra E; Bhushan, Anil


    Replication of beta cells is an important source of beta-cell expansion in early childhood. The recent linkage of type 2 diabetes with several transcription factors involved in cell cycle regulation implies that growth of the beta-cell mass in early childhood might be an important determinant of risk for type 2 diabetes. Under some circumstances, including obesity and pregnancy, the beta-cell mass is adaptively increased in adult humans. The mechanisms by which this adaptive growth occurs and the relative contributions of beta-cell replication or of mechanisms independent of beta-cell replication are unknown. Also, although there is interest in the potential for beta-cell regeneration as a therapeutic approach in both type 1 and 2 diabetes, little is yet known about the potential sources of new beta cells in adult humans. In common with other cell types, replicating beta cells have an increased vulnerability to apoptosis, which is likely to limit the therapeutic value of inducing beta-cell replication in the proapoptotic environment of type 1 and 2 diabetes unless applied in conjunction with a strategy to suppress increased apoptosis.

  18. Cyclic modular beta-sheets. (United States)

    Woods, R Jeremy; Brower, Justin O; Castellanos, Elena; Hashemzadeh, Mehrnoosh; Khakshoor, Omid; Russu, Wade A; Nowick, James S


    The development of peptide beta-hairpins is problematic, because folding depends on the amino acid sequence and changes to the sequence can significantly decrease folding. Robust beta-hairpins that can tolerate such changes are attractive tools for studying interactions involving protein beta-sheets and developing inhibitors of these interactions. This paper introduces a new class of peptide models of protein beta-sheets that addresses the problem of separating folding from the sequence. These model beta-sheets are macrocyclic peptides that fold in water to present a pentapeptide beta-strand along one edge; the other edge contains the tripeptide beta-strand mimic Hao [JACS 2000, 122, 7654] and two additional amino acids. The pentapeptide and Hao-containing peptide strands are connected by two delta-linked ornithine (deltaOrn) turns [JACS 2003, 125, 876]. Each deltaOrn turn contains a free alpha-amino group that permits the linking of individual modules to form divalent beta-sheets. These "cyclic modular beta-sheets" are synthesized by standard solid-phase peptide synthesis of a linear precursor followed by solution-phase cyclization. Eight cyclic modular beta-sheets 1a-1h containing sequences based on beta-amyloid and macrophage inflammatory protein 2 were synthesized and characterized by 1H NMR. Linked cyclic modular beta-sheet 2, which contains two modules of 1b, was also synthesized and characterized. 1H NMR studies show downfield alpha-proton chemical shifts, deltaOrn delta-proton magnetic anisotropy, and NOE cross-peaks that establish all compounds but 1c and 1g to be moderately or well folded into a conformation that resembles a beta-sheet. Pulsed-field gradient NMR diffusion experiments show little or no self-association at low (

  19. 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


    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)

  20. Integration of BETA with Eclipse

    DEFF Research Database (Denmark)

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


    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...

  1. Measurements of sin 2 $\\beta$

    CERN Document Server

    Tricomi, A


    A review of the most recent measurements of the CP violating parameter sin 2 beta from LEP and CDF is reported. These yield an average value of sin 2 beta =0.91+or-0.35, giving a confidence level that CP violation in the B system has been observed of almost 99%. (10 refs).

  2. Beta decay of Cu-56

    NARCIS (Netherlands)

    Borcea, R; Aysto, J; Caurier, E; Dendooven, P; Doring, J; Gierlik, M; Gorska, M; Grawe, H; Hellstrom, M; Janas, Z; Jokinen, A; Karny, M; Kirchner, R; La Commara, M; Langanke, K; Martinez-Pinedo, G; Mayet, P; Nieminen, A; Nowacki, F; Penttila, H; Plochocki, A; Rejmund, M; Roeckl, E; Schlegel, C; Schmidt, K; Schwengner, R; Sawicka, M


    The proton-rich isotope Cu-56 was produced at the GSI On-Line Mass Separator by means of the Si-28(S-32, p3n) fusion-evaporation reaction. Its beta -decay properties were studied by detecting beta -delayed gamma rays and protons. A half-Life of 93 +/- 3 ms was determined for Cu-56. Compared to the p

  3. Beta Function and Anomalous Dimensions

    DEFF Research Database (Denmark)

    Pica, Claudio; Sannino, Francesco


    We demonstrate that it is possible to determine the coefficients of an all-order beta function linear in the anomalous dimensions using as data the two-loop coefficients together with the first one of the anomalous dimensions which are universal. The beta function allows to determine the anomalou...

  4. Scintillation spectroscopy for beta ray dose measurements

    Energy Technology Data Exchange (ETDEWEB)

    Vapirev, E.I.; Jordanov, T.; Amin, S.; Stoilov, N.; Georgieva, K. [Sofia Univ. (Bulgaria). Fizicheski Fakultet


    Two methods have been developed and tested for the measurement of beta ray dose with a scintillation probe. According to the first method the energy absorbed in plastic filters is calculated from the difference between the energy E of the incident and filtered beta spectrum with an expression of the type E {approx} c{Sigma}iN(i)/{Delta}m, where c is a calibration constant (keV per channel), i is the channel number, N(i) is the detected beta spectrum, and {Delta}m is the filter thickness. According to the second `dE/dx` method the energy deposited in the surface layer of the scintillator is calculated by E {approx} c{Sigma}dE/dx(i)N(i), where dE/dx is the specific energy loss for tissue-equivalent media. The methods were tested for the cases of normally incident electrons and surface contamination. The scintillation probe used is stillbene and the test sources are thin {sup 90}Sr/{sup 90}Y and {sup 137}Cs. The results are close to the expected doses as calculated by Monte Carlo simulations. (Author).

  5. 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)


    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.

  6. A comparison of the activities of three beta-galactosidases in aqueous-organic solvent mixtures

    NARCIS (Netherlands)

    Yoon, JH; Mckenzie, D


    The hydrolytic activities of beta-galactosidases from three different sources have been determined in various 50% (v/v) organic solvent-buffer mixtures with a view to finding solvent systems of reduced water content suitable for the synthesis of glycosides and oligosaccharides. K. fragilis beta-gala

  7. [Serum beta 2 microglobulin (beta 2M) following renal transplantation]. (United States)

    Pacheco-Silva, A; Nishida, S K; Silva, M S; Ramos, O L; Azjen, H; Pereira, A B


    Although there was an important improvement in graft and patient survival the last 10 years, graft rejection continues to be a major barrier to the success of renal transplantation. Identification of a laboratory test that could help to diagnose graft rejection would facilitate the management of renal transplanted patients. PURPOSE--To evaluate the utility of monitoring serum beta 2M in recently transplanted patients. METHODS--We daily determined serum beta 2M levels in 20 receptors of renal grafts (10 from living related and 10 from cadaveric donors) and compared them to their clinical and laboratory evolution. RESULTS--Eight patients who presented immediate good renal function following grafting and did not have rejection had a mean serum beta 2M of 3.7 mg/L on the 4th day post transplant. The sensitivity of the test for the diagnosis of acute rejection was 87.5%, but the specificity was only 46%. Patients who presented acute tubular necrosis (ATN) without rejection had a progressive decrease in their serum levels of beta 2M, while their serum creatinine changed as they were dialyzed. In contrast, patients with ATN and concomitance of acute rejection or CSA nephrotoxicity presented elevated beta 2M and creatinine serum levels. CONCLUSION--Daily monitoring of serum beta 2M does not improve the ability to diagnose acute rejection in patients with good renal function. However, serum beta 2M levels seemed to be useful in diagnosing acute rejection or CSA nephrotoxicity in patients with ATN.

  8. Absorption of Beta Particles in Different Materials: An Undergraduate Experiment (United States)

    La Rocca, Paola; Riggi, Francesco


    The absorption of beta rays from a radioactive source in different materials was investigated by the use of a simple setup based on a Geiger counter and a set of absorber sheets. The number of electrons traversing the material was measured as a function of its thickness. Detailed GEANT simulations were carried out to reproduce the obtained…

  9. Intravenous glucose preparation as the source of an outbreak of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae infections in the neonatal unit of a regional hospital in KwaZulu-Natal. (United States)

    Moodley, Prashini; Coovadia, Yacoob M; Sturm, A Willem


    In the last week of May 2005, staff at Mahatma Gandhi Memorial Hospital in KwaZulu-Natal realised that many babies in the high-care nursery ward had bloodstream infections involving Klebsiella pneumoniae bacteria. Attempts to identify a common source of infection failed. The ward was therefore closed and new babies needing high care were admitted to another empty ward. Despite this, babies still became infected. This resulted in a request for assistance from the Department of Medical Microbiology of the Nelson R Mandela School of Medicine. A search for common factors through case history studies of the 26 infected babies showed that blood cultures of the babies remained positive despite the administration of appropriate antibiotics. Different options that could explain this were investigated. The organism was found in intravenous glucose preparations used for multiple dosing. Unopened vials of the same medication were sterile. The nursery was found to lack proper hand-wash facilities and to be overcrowded and understaffed. Reinforcement of hand hygiene and a ban on the multiple dosing of medicines stopped the outbreak. In conclusion, this outbreak resulted from a combination of factors among which lack of hand hygiene and multiple dosing of an intravenous glucose preparation were most significant.

  10. Detailed transcriptome atlas of the pancreatic beta cell

    Directory of Open Access Journals (Sweden)

    Eizirik Decio L


    Full Text Available Abstract Background Gene expression patterns provide a detailed view of cellular functions. Comparison of profiles in disease vs normal conditions provides insights into the processes underlying disease progression. However, availability and integration of public gene expression datasets remains a major challenge. The aim of the present study was to explore the transcriptome of pancreatic islets and, based on this information, to prepare a comprehensive and open access inventory of insulin-producing beta cell gene expression, the Beta Cell Gene Atlas (BCGA. Methods We performed Massively Parallel Signature Sequencing (MPSS analysis of human pancreatic islet samples and microarray analyses of purified rat beta cells, alpha cells and INS-1 cells, and compared the information with available array data in the literature. Results MPSS analysis detected around 7600 mRNA transcripts, of which around a third were of low abundance. We identified 2000 and 1400 transcripts that are enriched/depleted in beta cells compared to alpha cells and INS-1 cells, respectively. Microarray analysis identified around 200 transcription factors that are differentially expressed in either beta or alpha cells. We reanalyzed publicly available gene expression data and integrated these results with the new data from this study to build the BCGA. The BCGA contains basal (untreated conditions gene expression level estimates in beta cells as well as in different cell types in human, rat and mouse pancreas. Hierarchical clustering of expression profile estimates classify cell types based on species while beta cells were clustered together. Conclusion Our gene atlas is a valuable source for detailed information on the gene expression distribution in beta cells and pancreatic islets along with insulin producing cell lines. The BCGA tool, as well as the data and code used to generate the Atlas are available at the T1Dbase website (

  11. Experiments on double beta decay

    Energy Technology Data Exchange (ETDEWEB)

    Busto, J. [Neuchatel Univ. (Switzerland). Inst. de Physique


    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.

  12. An essay on Bion's beta function. (United States)

    Oliner, Marion M


    Among the major theorists studying the effect of the external world on the individual, none had a more ambiguous relationship to the psychic manifestations of the environment than Wilfred Bion. On the one hand his theory of the mind contained a new concept, beta elements, to depict the intrusion of the material world into the mental sphere, while on the other he radically opposed the use of sensory perception as a source for clinical insight. The author examines this dichotomy as an outgrowth of her interest in the place of external reality in psychoanalytic theory. As a result, this essay is an attempt to clarify the source for Bion's theorizing, in order to be more specific about the applicability of his concepts and his precepts.

  13. Evolution of outer membrane beta-barrels from an ancestral beta beta hairpin. (United States)

    Remmert, M; Biegert, A; Linke, D; Lupas, A N; Söding, J


    Outer membrane beta-barrels (OMBBs) are the major class of outer membrane proteins from Gram-negative bacteria, mitochondria, and plastids. Their transmembrane domains consist of 8-24 beta-strands forming a closed, barrel-shaped beta-sheet around a central pore. Despite their obvious structural regularity, evidence for an origin by duplication or for a common ancestry has not been found. We use three complementary approaches to show that all OMBBs from Gram-negative bacteria evolved from a single, ancestral beta beta hairpin. First, we link almost all families of known single-chain bacterial OMBBs with each other through transitive profile searches. Second, we identify a clear repeat signature in the sequences of many OMBBs in which the repeating sequence unit coincides with the structural beta beta hairpin repeat. Third, we show that the observed sequence similarity between OMBB hairpins cannot be explained by structural or membrane constraints on their sequences. The third approach addresses a longstanding problem in protein evolution: how to distinguish between a very remotely homologous relationship and the opposing scenario of "sequence convergence." The origin of a diverse group of proteins from a single hairpin module supports the hypothesis that, around the time of transition from the RNA to the protein world, proteins arose by amplification and recombination of short peptide modules that had previously evolved as cofactors of RNAs.

  14. Questions Students Ask: Beta Decay. (United States)

    Koss, Jordan; Hartt, Kenneth


    Answers a student's question about the emission of a positron from a nucleus. Discusses the problem from the aspects of the uncertainty principle, beta decay, the Fermi Theory, and modern physics. (YP)

  15. Formation and Degradation of Beta-casomorphins in Dairy Processing


    Nguyen, Duc Doan; Johnson, Stuart Keith; Busetti, Francesco; Solah, Vicky Ann


    Milk proteins including casein are sources of peptides with bioactivity. One of these peptides is beta-casomorphin (BCM) which belongs to a group of opioid peptides formed from β-casein variants. Beta-casomorphin 7 (BCM7) has been demonstrated to be enzymatically released from the A1 or B β-casein variant. Epidemiological evidence suggests the peptide BCM 7 is a risk factor for development of human diseases, including increased risk of type 1 diabetes and cardiovascular diseases but this has ...

  16. Spectrochemical studies with {beta}-emitting radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Chesta, Miguel A.; Plivelic, Tomas S.; Mainardi, Raul T. [Cordoba Univ. Nacional (Argentina). Facultad de Matematica, Atronomia y Fisica


    Electrons emitted by {sup 90} Sr radioactive source and positrons from a {sup 22} Na source were used to produce ionizations in the constituents of a sample. The sources have similar energy spectra and this allowed us to compare the characteristic radiation emission efficiencies. The new proposed experimental set up for radioisotope excited x-ray fluorescence analysis (XRFA) is of a transparent source type and provides at least a ten times increase in the intensity of characteristic x-rays emitted by the sample as compared with a standard set up in XRFA. It is shown that this fact, together with the relatively high energy of the beta particles, make it possible to carry out a mirror elemental analysis in a few minutes using low intensity radioactive sources (no special handling license). Preliminary experimental results are shown using both electrons and positrons impinging on pure and composed samples and simple analytical expressions are provided for the characteristic radiation intensity as detected by an HPGe detector. (author). 7 refs., 4 figs.

  17. Beta Function and Anomalous Dimensions

    CERN Document Server

    Pica, Claudio


    We demonstrate that it is possible to determine the coefficients of an all-order beta function linear in the anomalous dimensions using as data the two-loop coefficients together with the first one of the anomalous dimensions which are universal. The beta function allows to determine the anomalous dimension of the fermion masses at the infrared fixed point, and the resulting values compare well with the lattice determinations.

  18. Polypeptides having beta-glucosidase activity, beta-xylosidase activity, or beta-glucosidase and beta-xylosidase activity and polynucleotides encoding same

    Energy Technology Data Exchange (ETDEWEB)

    Morant, Marc


    The present invention relates to isolated polypeptides having beta-glucosidase activity, beta-xylosidase activity, or beta-glucosidase and beta-xylosidase activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

  19. The Majorana Neutrinoless Double-Beta Decay Experiment

    CERN Document Server

    Guiseppe, V E


    Neutrinoless double-beta decay searches play a major role in determining the nature of neutrinos, the existence of a lepton violating process, and the effective Majorana neutrino mass. The Majorana Collaboration proposes to assemble an array of HPGe detectors to search for neutrinoless double-beta decay in Ge-76. Our proposed method uses the well-established technique of searching for neutrinoless double-beta decay in high purity Ge-diode radiation detectors that play both roles of source and detector. The technique is augmented with recent improvements in signal processing and detector design, and advances in controlling intrinsic and external backgrounds. Initially, Majorana aims to construct a prototype module containing 60 kg of Ge detectors to demonstrate the potential of a future 1-tonne experiment. The design and potential reach of this prototype Demonstrator module will be presented. This paper will also discuss detector optimization and low-background requirements, such as material purity, background...

  20. (Depth-dose curves of the beta reference fields (147)Pm, (85)Kr and (90)Sr/(90)Y produced by the beta secondary standard BSS2. (United States)

    Brunzendorf, Jens


    The most common reference fields in beta dosimetry are the ISO 6980 series 1 radiation fields produced by the beta secondary standard BSS2 and its predecessor BSS. These reference fields require sealed beta radiation sources ((147)Pm, (85)Kr or (90)Sr/(90)Y) in combination with a source-specific beam-flattening filter, and are defined only at a given distance from the source. Every radiation sources shipped with the BSS2 is sold with a calibration certificate of the Physikalisch-Technische Bundesanstalt. The calibration workflow also comprises regular depth-dose measurements. This work publishes complete depth-dose curves of the series 1 sources (147)Pm, (85)Kr and (90)Sr/(90)Y in ICRU tissue up to a depth of 11 mm,when all electrons are stopped. For this purpose, the individual depth-dose curves of all BSS2 sources calibrated so far have been determined, i.e. the complete datasets of all BSS2 beta sources have been re-evaluated. It includes 191 depth-dose curves of 116 different sources comprising more than 2200 data points in total. Appropriate analytical representations of the nuclide-specific depth-dose curves are provided for the first time.

  1. In-trap decay spectroscopy for {beta}{beta} decays

    Energy Technology Data Exchange (ETDEWEB)

    Brunner, Thomas


    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

  2. Analysis of betaS and betaA genes in a Mexican population with African roots. (United States)

    Magaña, María Teresa; Ongay, Zoyla; Tagle, Juan; Bentura, Gilberto; Cobián, José G; Perea, F Javier; Casas-Castañeda, Maricela; Sánchez-López, Yoaly J; Ibarra, Bertha


    To investigate the origin of the beta(A) and beta(S) genes in a Mexican population with African roots and a high frequency of hemoglobin S, we analyzed 467 individuals (288 unrelated) from different towns in the states of Guerrero and Oaxaca in the Costa Chica region. The frequency of the sickle-cell trait was 12.8%, which may represent a public health problem. The frequencies of the beta-haplotypes were determined from 350 nonrelated chromosomes (313 beta(A) and 37 beta(S)). We observed 15 different beta(A) haplotypes, the most common of which were haplotypes 1 (48.9%), 2 (13.4%), and 3 (13.4%). The calculation of pairwise distributions and Nei's genetic distance analysis using 32 worldwide populations showed that the beta(A) genes are more closely related to those of Mexican Mestizos and North Africans. Bantu and Benin haplotypes and haplotype 9 were related to the beta(S) genes, with frequencies of 78.8, 18.2, and 3.0%, respectively. Comparison of these haplotypes with 17 other populations revealed a high similitude with the population of the Central African Republic. These data suggest distinct origins for the beta(A) and beta(S) genes in Mexican individuals from the Costa Chica region.

  3. beta (+)-Thalassaemia in the Po river delta region (northern Italy): genotype and beta globin synthesis. (United States)

    Del Senno, L; Pirastu, M; Barbieri, R; Bernardi, F; Buzzoni, D; Marchetti, G; Perrotta, C; Vullo, C; Kan, Y W; Conconi, F


    Six beta(+)-thalassaemic patients from the Po river delta region have been studied. Using synthetic oligonucleotides as specific hybridisation probes, the beta(+) IVS I mutation (G----A at position 108) was demonstrated. This lesion and the enzyme polymorphism pattern in the subjects examined are the same as have been described for other Mediterranean beta(+)-thalassaemias. Antenatal diagnosis through DNA analysis of beta(+)-thalassaemia is therefore possible. The production of beta globin in a beta(+), homozygote and in a beta (+), beta(0) 39 (nonsense mutation at codon 39) double heterozygote is approximately 20% and 10% respectively of total non-alpha globin synthesis. Despite some overlapping of the results, similar beta globin synthesis levels have been obtained in 43 beta(+)-thalassaemia patients. This suggests that in the Po river delta region the most common thalassaemic genes are beta(0) 39 and beta(+) IVS I. Images PMID:2580095

  4. Beta-carotene from cassava (Manihot esculenta Crantz) leaves improves vitamin A status in rats. (United States)

    Siqueira, Egle Machado de Almeida; Arruda, Sandra Fernandes; de Vargas, Rodrigo Martins; de Souza, Elizabeth Maria Talá


    The bioavailability of beta-carotene from cassava (Manihot esculenta Crantz) leaves was assayed in vitamin A deficient Wistar rats (Rattus norvegicus). Rats were separated into three groups and fed with a modified AIN-93G--vitamin A deficient--diet. Deficient rat received this diet without any additional vitamin A source. Controls received the diet with 7200 microg of synthetic beta-carotene (control), while experimentals (test) received 19.5 g of cassava leaves powder per kg of diet. The cassava leaves with beta-carotene promotes similar growth and tissue weight in rats to the synthetic beta-carotene. The relative bioavailability, estimated as the Retinol Accumulation Factor (RAF), was 16.5 and 27.5 for control and test groups, respectively, indicating that control and test rats should have an intake of 16.5 microg or 27.5 microg of beta-carotene from synthetic form or cassava leaves powder for each 1 microg of hepatic retinol stored, respectively. The cassava leaves beta-carotene bioavailability was lower than the synthetic beta-carotene probably because the beta-carotene from the leaf matrix may be bounded to protein complex or inside organelles, which impair carotenoid absorption. Our findings showed that beside the hepatic retinol recovery, cassava leaf beta-carotene could maintain rat growth and avoid vitamin A deficient symptoms.

  5. Remote Sensing of Alpha and Beta Sources - Modeling Summary

    Energy Technology Data Exchange (ETDEWEB)

    Dignon, J; Frank, M; Cherepy, N


    Evaluating the potential for optical detection of the products of interactions of energetic electrons or other particles with the background atmosphere depends on predictions of change in atmospheric concentrations of species which would generate detectable spectral signals within the range of observation. The solar blind region of the spectrum, in the ultra violet, would be the logical band for outdoor detection (see Figure 1). The chemistry relevant to these processes is composed of ion-molecule reactions involving the initially created N{sub 2}{sup +} and O{sub 2}{sup +} ions, and their subsequent interactions with ambient trace atmospheric constituents. Effective modeling of the atmospheric chemical system acted upon by energetic particles requires knowledge of the dominant mechanism that exchange charge and associate it with atmospheric constituents, kinetic parameters of the individual processes (see e.g. Brasseur and Solomon, 1995), and a solver for the coupled differential equations that is accurate for the very stiff set of time constants involved. The LLNL box model, VOLVO, simulates the diel cycle of trace constituent photochemistry for any point on the globe over the wide range of time scales present using a stiff Gear-type ODE solver, i.e. LSODE. It has been applied to problems such as tropospheric and stratospheric nitrogen oxides, stratospheric ozone production and loss, and tropospheric hydrocarbon oxidation. For this study we have included the appropriate ion flux.

  6. Platelets possess functional TGF-beta receptors and Smad2 protein. (United States)

    Lev, P R; Salim, J P; Marta, R F; Osorio, M J Mela; Goette, N P; Molinas, F C


    TGF-beta1 plays a main role in tissue repair by regulating extracellular matrix production and tissue granulation. Platelets are one of the main sources of this cytokine in the circulation. The aim of this study was to evaluate the presence of the TGF-beta receptors on platelets, the effect of TGF-beta1 on platelet aggregation and the underlying intracellular mechanisms. TGF-beta receptors on platelets were studied by flow cytometry and their mRNA by PCR. Platelet aggregation was assessed by turbidimetric methods and intracellular pathways by Western blot. TGF-beta receptor type II and mRNA codifying for TbetaRI and TbetaRII were found in platelets. We demonstrated that TGF-beta1 did not trigger platelet aggregation by itself but had a modulating effect on ADP-induced platelet aggregation. Either inhibition or increase in platelet aggregation, depending on the exposure time to TGF-beta1 and the ADP concentration used, were shown. We found that platelets possess Smad2 protein and that its phosphorylation state is increased after exposure to TGF-beta1. Besides, TGF-beta1 modified the pattern of ADP-induced tyrosine phosphorylation. Increased phosphorylation levels of 64-, 80- and 125-kDa proteins during short time incubation with TGF-beta1 and increased phosphorylation of 64- and 125-kDa proteins after longer incubation were observed. The modulating effect of TGF-beta1 on platelet aggregation could play a role during pathological states in which circulating TGF-beta1 levels are increased and intravascular platelet activation is present, such as myeloproliferative disorders. In vascular injury, in which platelet activation followed by granule release generates high local ADP concentrations, it could function as a physiological mechanism of platelet activation control.

  7. Smart Beta or Smart Alpha

    DEFF Research Database (Denmark)

    Winther, Kenneth Lillelund; Steenstrup, Søren Resen


    Smart beta has become the flavor of the decade in the investment world with its low fees, easy access to rewarded risk premiums, and appearance of providing good investment results relative to both traditional passive benchmarks and actively managed funds. Although we consider it well documented...... 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......-documented smart beta risk premiums and still motivate active managers to avoid value traps, too highly priced small caps, defensives, etc. By constructing the equity portfolios of active managers that resemble the most widely used risk premiums, we show that the returns and risk-adjusted returns measures...

  8. The microbial oxidation of (-)-beta-pinene by Botrytis cinerea. (United States)

    Farooq, Afgan; Choudhary, M Iqbal; Tahara, Satoshi; Rahman, Atta-ur; Başer, K Hüsnü Can; Demirci, Fatih


    (-)-beta-pinene, a flavor and fragrance monoterpene is an important constituent of essential oils of many aromatic plants. It was oxidized by a plant-pathogenic fungus, Botrytis cinerea to afford four metabolites characterized as (-)-6a-hydroxy-beta-pinene, (-)-4beta,5beta-dihydroxy-beta-pinene, (-)-2beta,3beta-dihydroxypinane, and (-)-4beta-hydroxy-beta-pinene-6-one by detailed spectroscopic studies along with other known metabolites.

  9. Neutrinoless double beta decay experiments

    CERN Document Server

    Zuber, K


    The study of neutrinoless double beta decay is of outmost importance for neutrino physics. It is considered to be the gold plated channel to probe the fundamental character of neutrinos and to determine the neutrino mass. From the experimental point about nine different isotopes are explored for the search. After a general introduction follows a short discussion on nuclear matrix element calculations and supportive measurements. The current experimental status of double beta searches is presented followed by a short discussion of the ideas and proposals for large scale experiments.

  10. A {beta} - {gamma} coincidence; Metodo de coincidencias {beta} - {gamma}

    Energy Technology Data Exchange (ETDEWEB)

    Agullo, F.


    A {beta} - {gamma} coincidence method for absolute counting is given. The fundamental principles are revised and the experimental part is detailed. The results from {sup 1}98 Au irradiated in the JEN 1 Swimming pool reactor are given. The maximal accuracy is 1 per cent. (Author) 11 refs.

  11. Beta thalassaemia mutations in Turkish Cypriots. (United States)

    Sozuoz, A; Berkalp, A; Figus, A; Loi, A; Pirastu, M; Cao, A


    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 of a large scale prevention programme based on fetal diagnosis of beta thalassaemia by DNA analysis in the Turkish population. PMID:3236356

  12. Measurement of the 2{nu}{beta}{beta} decay of {sup 100}Mo to the excited 0{sub 1}{sup +} state in the NEMO3 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Vala, L


    The NEMO3 detector was designed for the study of double beta decay and in particular to search for the neutrinoless double beta decay process (0{nu}{beta}{beta}). The intended sensitivity in terms of a half-life limit for the 0{nu}{beta}{beta} decay is of the order of 10{sup 25} y which corresponds to an effective neutrino mass m{sub {nu}} on the level of (0.3 - 0.1) eV. The 0{nu}{beta}{beta} process is today the most promising test of the Majorana nature of the neutrino. The detector was constructed in the Modane Underground Laboratory (LSM) in France by an international collaboration including France, Russia, the Czech Republic, the USA, the UK, Finland, and Japan. The experiment has been taking data since May 2002. The quantity of {sup 100}Mo in the detector (7 kg) allows an efficient measurement of the two-neutrino double beta decay (2{nu}{beta}{beta}) of {sup 100}Mo to the excited 0{sub 1}{sup +} state (eeN{gamma} channel). Monte-Carlo simulations of the effect and of all the relative sources of background have been produced in order to define a set of appropriate selection criteria. Both Monte-Carlo simulations and special runs with sources of {sup 208}Tl and {sup 214}Bi showed that the only significant background in the eeN{gamma} channel comes from radon that penetrated inside the wire chamber of NEMO3. The experimental data acquired from May 2002 to May 2003 have been analysed in order to determine the signal from the 2{nu}{beta}{beta} decay of {sup 100}Mo to the excited 0{sub 1}{sup +} state and the corresponding background level. The physical result, which was obtained at the level of four standard deviations, is given in the form of an interval of half-life values at 95% confidence level: [5.84*10{sup 20}, 2.26*10{sup 21}] y for method A and [5.83*10{sup 20}, 1.71*10{sup 21}] y for method B. (author)

  13. Implications of alpha-amylase production and beta-glucuronidase expression in Escherichia coli strains. (United States)

    Caldini, G; Strappini, C; Trotta, F; Cenci, G


    Two Escherichia coli strains in which alpha-amylase production differed were used to study in depth some characteristics related to beta-glucuronidase induction by starch. The beta-glucuronidase background activity in Luria broth medium was comparable for the two isolates, but only amylase positive S1 was able to grow on starch molecules supplied as the sole carbon source. In this case growth resulted at higher beta-glucuronidase levels (p beta-glucuronidase activity of amylase negative M94 remained unchanged during starvation on starch medium, but an induced response was observed with methylumbelliferyl-glucuronide. These results further support the hypothesis that starch metabolism is involved in the complex beta-glucuronidase regulation of E. coli strains. This is relevant not only for basic research but also to investigating gut microbial enzymology.

  14. Effect of Addition of Cereal Based Beta-glucan on Technological and Functional Properties of Foods

    Directory of Open Access Journals (Sweden)

    Nihal Şimşekli


    Full Text Available Nowadays usage of dietary fibers in foods has been increasing duo to revealing of health benefits. Beta-glucans found especially in oats and barley, are polysaccharide and source of water-soluble dietary fiber. Positive effects of beta-glucans like healing coronary-heart disease, lowering blood cholesterol level, balancing blood sugar level and preventing obesity, made beta-glucans widespread functional food components for producing various foods. In addition to beneficial physiological effects of beta-glucans, they texturize, gelatinize, emulsify and stabilize the foods. They increase viscosity, replace fat and enhance rheological properties in cereal, meat and dairy products. They are also used to produce packing material depending on their mechanical properties and molecular weights. In this review, effects of addition of cereal based beta-glucans on technological and functional properties of various foods are revealed based on previous studies.

  15. Screening of beta-glucan contents in commercially cultivated and wild growing mushrooms. (United States)

    Sari, Miriam; Prange, Alexander; Lelley, Jan I; Hambitzer, Reinhard


    Mushrooms have unique sensory properties and nutritional values as well as health benefits due to their bioactive compounds, especially beta-glucans. Well-known edible and medicinal mushroom species as well as uncommon or unknown species representing interesting sources of bioactive beta-glucans have been widely studied. Commercially cultivated and wild growing mushrooms were analysed for their beta-glucan contents. Enzymatic determinations of all glucans, alpha-glucans and beta-glucans in 39 mushrooms species were performed, leading to very remarkable results. Many wild growing species present high beta-glucan contents, especially Bracket fungi. The well-known cultivated species Agaricus bisporus, Lentinula edodes and Cantharellus cibarius as well as most screened wild growing species show higher glucan contents in their stipes than caps.

  16. Intermediate γ beta beams with a cluster of detectors (United States)

    Meloni, D.; Mena, O.; Orme, C.; Palomares-Ruiz, S.; Pascoli, S.


    The acceleration of radionuclides in a beta beam provides an alternative experimental design to superbeam and neutrino factory long baseline neutrino oscillation experiments. Only single baseline beta beam scenarios have been considered thus far although a storage ring could source at least two baselines. The multitude of possible detector sites in Europe potentially allows for numerous baselines for future long baseline experiments sourced at CERN. Here, we will consider an example taking the CERN-Canfranc and CERN-Boulby baselines. We present results that indicate good sensitivity to the mass hierarchy for values of sin2 2θ13 as small as 10-3 and CP-violation discovery for sin2 2θ13 down to 10-4. These results are achieved with a single helicity since the second baseline provides the synergies usually associated with an anti-neutrino run.

  17. Beta-carotene and the application of transcriptomics in risk-benefit evaluation of natural dietary components

    NARCIS (Netherlands)

    Keijer, J.; Bunschoten, J.E.; Palou, A.; Franssen-Hal, van N.L.W.


    Beta-carotene is a natural food component that is present in fruits and vegetables and is also used as a food colorant and a supplement. Beta-carotene is an anti-oxidant and a source of vitamin A. It is endowed with health beneficial properties, but a number of studies showed that with high intakes

  18. Beta Cell Workshop 2013 Kyoto

    DEFF Research Database (Denmark)

    Heller, R Scott; Madsen, Ole D; Nielsen, Jens Høiriis


    The very modern Kyoto International Conference Center provided the site for the 8th workshop on Beta cells on April 23-26, 2013. The preceding workshops were held in Boston, USA (1991); Kyoto, Japan (1994); Helsingør, Denmark (1997); Helsinki, Finland (2003); El Perello, Spain (2006); Peebles...

  19. Estimating $\\beta$-mixing coefficients

    CERN Document Server

    McDonald, Daniel J; Schervish, Mark


    The literature on statistical learning for time series assumes the asymptotic independence or ``mixing' of the data-generating process. These mixing assumptions are never tested, nor are there methods for estimating mixing rates from data. We give an estimator for the $\\beta$-mixing rate based on a single stationary sample path and show it is $L_1$-risk consistent.

  20. Beta-carotene as antioxidant

    NARCIS (Netherlands)

    Bast, A.; Plas, R.M. van der; Berg, H. van den; Haenen, G.R.M.M.


    Objective: Beta-carotene has been shown to exhibit a good radical-trapping antioxidant activity in vitro. We were interested to see if dietary β-carotene in combination with various intake levels for vitamin A would also inhibit lipid peroxidation. Design: Sixty male Wistar rats received vitamin A (

  1. Neutron Beta Decay Studies with Nab

    CERN Document Server

    Baeßler, S; Alonzi, L P; Balascuta, S; Barrón-Palos, L; Bowman, J D; Bychkov, M A; Byrne, J; Calarco, J R; Chupp, T; Vianciolo, T V; Crawford, C; Frlež, E; Gericke, M T; Glück, F; Greene, G L; Grzywacz, R K; Gudkov, V; Harrison, D; Hersman, F W; Ito, T; Makela, M; Martin, J; McGaughey, P L; McGovern, S; Page, S; Penttilä, S I; Počanić, D; Rykaczewski, K P; Salas-Bacci, A; Tompkins, Z; Wagner, D; Wilburn, W S; Young, A R


    Precision measurements in neutron beta decay serve to determine the coupling constants of beta decay and allow for several stringent tests of the standard model. This paper discusses the design and the expected performance of the Nab spectrometer.

  2. The beta-decay of Al-22

    NARCIS (Netherlands)

    Achouri, NL; Santos, FDO; Lewitowicz, M; Blank, B; Aysto, J; Canchel, G; Czajkowski, S; Dendooven, P; Emsallem, A; Giovinazzo, J; Guillet, N; Jokinen, A; Larid, AM; Longour, C; Perajarvi, K; Smirnova, N; Stanoiu, M


    In an experiment performed at the LISE3 facility of GANIL, we studied the decay of Al-22 produced by the fragmentation of a Ar-36 primary beam. A beta-decay half-life of T-1/2 = 91.1 +/- 0.5ms was measured. The beta-delayed one- and two-proton emission as well as beta-alpha and beta-delayed gamma-de

  3. Traumatic Brain Injury, Microglia, and Beta Amyloid


    Mannix, Rebekah C.; Whalen, Michael J


    Recently, there has been growing interest in the association between traumatic brain injury (TBI) and Alzheimer's Disease (AD). TBI and AD share many pathologic features including chronic inflammation and the accumulation of beta amyloid (A\\(\\beta\\)). Data from both AD and TBI studies suggest that microglia play a central role in A\\(\\beta\\) accumulation after TBI. This paper focuses on the current research on the role of microglia response to A\\(\\beta\\) after TBI.

  4. Síntesis y caracterización de la zeolita Beta

    Directory of Open Access Journals (Sweden)

    Mahiceth Quintero


    Full Text Available Beta zeolite is normally obtained with Si/Al 5 and infinity ratios, using tetraethylammonium (TEA as templante. Important parameters in the TEA-Beta synthesis are alkali cation concentration, the type of cation used, the concentration of hydroxide, and the amount of templante, the temperature and the source of silica used. The synthesis with ratios Si:Al above 80 are generally quite difficult to achieve, but have recently been reported with all silica synthesis using TEA as templante. Their main applications are in the catalytic processes of hydrocarbon transformation (alkylation, in the inorganic membrane preparation and like “seed” in the synthesis of other zeolites. It is a microporous solid, with a unique system of channels and characteristic a chemical composition. In this work Beta zeolite was synthesized with aluminum sulfate like aluminum source. The phase identified in the pattern of X-ray diffraction obtained, coincides with the structure of the zeolite Beta.

  5. Beta- and gamma-range human lower limb corticomuscular coherence

    Directory of Open Access Journals (Sweden)

    Joseph T Gwin


    Full Text Available Coherence between electroencephalography (EEG recorded on the scalp above the motor cortex and electromyography (EMG recorded on the skin of the limbs is thought to reflect corticospinal coupling between motor cortex and muscle motor units. Beta-range (13-30 Hz corticomuscular coherence has been extensively documented during static force output while gamma-range (31-45 Hz coherence has been linked to dynamic force output. However, the explanation for this beta-to-gamma coherence shift remains unclear. We recorded 264-channel EEG and 8-channel lower limb electromyography (EMG while 8 healthy subjects performed isometric and isotonic, knee and ankle exercises. Adaptive mixture independent component analysis (AMICA parsed EEG into models of underlying source signals. We computed magnitude squared coherence between electrocortical source signals and EMG. Significant coherence between contralateral motor cortex electrocortical signals and lower limb EMG was observed in the beta- and gamma-range for all exercise types. Gamma-range coherence was significantly greater for isotonic exercises than for isometric exercises. We conclude that active muscle movement modulates the speed of corticospinal oscillations. Specifically, isotonic contractions shift corticospinal oscillations towards the gamma-range while isometric contractions favor beta-range oscillations. Prior research has suggested that tasks requiring increased integration of visual and somatosensory information may shift corticomuscular coherence to the gamma-range. The isometric and isotonic tasks studied here likely required similar amounts of visual and somatosensory integration. This suggests that muscle dynamics, including the amount and type of proprioception, may play a role in the beta-to-gamma shift.

  6. Beta and low-energy photon irradiation of several commercial phosphors

    Energy Technology Data Exchange (ETDEWEB)

    Fix, J.J.; Holbrook, K.L.; Soldat, K.L.


    Several commercially available thermoluminescent phosphors were evaluated with respect to their observed response to selected beta sources and K-fluorescent x rays. Phosphor responses were determined for in-air and on-phantom irradiations. Similar irradiations were done using a /sup 137/Cs source. Phosphor glow curves were recorded using a Harshaw Model 2080 TL Picoprocessor.

  7. Beta and low-energy photon irradiation of several commercial phosphors (United States)

    Fix, J. J.; Holbrook, K. L.; Soldat, K. L.


    Several commercially available thermoluminescent phosphors were evaluated with respect to their observed response to selected beta sources and K-fluorescent X rays. Phosphor responses were determined for in-air and on-phantom irradiations. Similar irradiations were done using a 137Cs source. Phosphor glow curves were recorded using a Harshaw Model 2080 TL Picoprocessor.

  8. Purification and characterisation of an extracellular fructan beta-fructosidase from a Lactobacillus pentosus strain isolated from fermented fish

    DEFF Research Database (Denmark)

    Paludan-Müller, Christine; Gram, Lone; Rattray, F.P.


    Lactobacillus pentosus B235, which was isolated as part of the dominant microflora from a garlic containing fermented fish product, was grown in a chemically defined medium With inulin as the sole carbohydrate source. An extracellular fructan beta- fructosidase was purified to homogeneity from...... fructan), but also hydrolysed garlic extract, (a beta(2-->1)-linked fructan with beta(2-->6)-linked fructosyl sidechains), 1,1,1-kestose, 1,1-kestose, 1-kestose, inulin (beta(2-->1)-linked fructans) and Sucrose at 60, 45, 39, 12, 9 and 3%, respectively, of the activity observed for levan. Melezitose...

  9. Purification and characterisation of an extracellular fructan beta-fructosidase from a Lactobacillus pentosus strain isolated from fermented fish

    DEFF Research Database (Denmark)

    Paludan-Müller, Christine; Gram, Lone; Rattray, Fergal P


    Lactobacillus pentosus B235, which was isolated as part of the dominant microflora from a garlic containing fermented fish product, was grown in a chemically defined medium with inulin as the sole carbohydrate source. An extracellular fructan beta-fructosidase was purified to homogeneity from...... fructan), but also hydrolysed garlic extract, (a beta(2-->1)-linked fructan with beta(2-->6)-linked fructosyl sidechains), 1,1,1-kestose, 1,1-kestose, 1-kestose, inulin (beta(2-->1)-linked fructans) and sucrose at 60, 45, 39, 12, 9 and 3%, respectively, of the activity observed for levan. Melezitose...


    NARCIS (Netherlands)



    We have identified a new protein fold-the alpha/beta-hydrolase fold-that is common to several hydrolytic enzymes of widely differing phylogenetic origin and catalytic function. The core of each enzyme is similar: an alpha/beta-sheet, not barrel, of eight beta-sheets connected by alpha-helices. These

  11. Beta-lactamases in Enterobacteriaceae in broilers

    NARCIS (Netherlands)

    Dierikx, C.M.


    Resistance to cephalosprins due to the production of extended spectrum beta-lactamases (ESBLs) or plasmid mediated AmpC beta-lactamases is increasingly found in infections in humans outside the hospital. The genes encoding for these beta-lactamases are located on mobile DNA (plasmids), which can be

  12. Higher-Order Beta Matching with Solutions in Long Beta-Eta Normal Form

    DEFF Research Database (Denmark)

    Støvring, Kristian


    up to beta-eta equivalence is a long-standing open problem.We show that higher-order matching up to beta-eta equivalence is decidable if and only if a restricted form of higher-order matching up to beta equivalence is decidable: the restriction is that solutions must be in long beta-eta normal form....

  13. Measurements of $L_{31}, L_{3}\\alpha, L_{3}\\beta, L_{2}\\beta, L_{2} \\gamma, L_{1}\\beta, L_{1}\\gamma, L_{\\beta}, L_{\\gamma}, L_{1x}, L_{2x}$ and $L_{3x}$ X-ray production cross sections and L subshell fluorescence

    CERN Document Server

    Ertugrul, M


    The L/sub 3l/, L/sub 3 alpha /, L/sub 3 beta /, L/sub 2 beta /, L/sub 2 gamma /, L/sub 1 beta /, L/sub 1 gamma /, L/sub beta /, L/sub gamma /, L/sub 1x/, L/sub 2x/ and L/sub 3x/ X-ray production cross sections in Re, W and Ta have been measured using the 59.5 keV incident photon energy. The measurements were performed using an Am-241 radioisotope as the photon source and a Si(Li) detector. The L X-rays are resolved with a new analytical method. The obtained L/sub l/, L/sub alpha /, L /sub 3 beta /, L/sub 2 beta /, L/sub 2 gamma /, L/sub 1 beta /, L/sub 1 gamma /, L/sub beta /, L/sub gamma /, L/sub 1x/, L/sub 2x/ and L /sub 3x/ X-rays are compared with the theoretical calculations using the most reliable theoretical values of L/sub i/ (i=1, 2, 3) subshell photoionization cross sections, fluorescence yields, X-ray emission rates and Coster-Kronig transition probabilities. The results in the present paper are found to be in good agreement with the calculated values. (23 refs).

  14. Effects of beta-glucan addition to a probiotic containing yogurt. (United States)

    Vasiljevic, T; Kealy, T; Mishra, V K


    This study investigated the effects of addition of beta-glucan from 2 different cereal sources (oat and barley) on growth and metabolic activity of Bifidobacterium animalis ssp. lactis (Bb-12) as determined by plating on a selective medium in yogurt during prolonged cold storage. These yogurt batches were compared to unsupplemented and inulin supplemented controls. All batches were also assessed for syneresis. Oat beta-glucan addition resulted in improved probiotic viability and stability comparable to that of inulin. It also enhanced lactic and propionic acid production. The barley beta-glucan addition suppressed proteolytic activity more than that from oat. These improvements were hindered by greater syneresis caused likely by thermodynamic incompatibility. Small amplitude oscillatory measurements of acidified model mixture of beta-glucan/skim milk solids showed formation of casein gel within the beta-glucan network. Binary mixtures of beta-glucan and skim milk solids had apparent pseudoplastic and non-Newtonian behavior governed mainly by beta-glucan contribution. Above critical concentrations, the mixtures underwent phase separation with the lower phase rich in protein. The phase diagram also showed that the addition of beta-glucan may be possible at or below 0.24 w/w%.

  15. Isozymes of beta-N-Acetylhexosaminidase from Pea Seeds (Pisum sativum L.). (United States)

    Harley, S M; Beevers, L


    Four isozymes of beta-N-acetylhexosaminidase (beta-NAHA) from pea seeds (Pisum sativum L.) have been separated, with one, designated beta-NAHA-II, purified to apparent homogeneity by means of an affinity column constructed by ligating p-aminophenyl-N-acetyl-beta-d-thioglucosaminide to Affi-Gel 202. The other three isozymes have been separated and purified 500- to 1750-fold by chromatography on Concanavalin A-Sepharose, Zn(2+) charged immobilized metal affinity chromatography, hydrophobic chromatography, and ion exchange chromatography on CM-Sephadex. All four isozymes are located in the protein bodies of the cotyledons. The molecular weight of each isozyme is 210,000. beta-NAHA-II is composed of two heterogenous subunits. The subunits are not held together by disulfide bonds, but sulfhydryl groups are important for catalysis. All four isozymes release p-nitrophenol from both p-nitrophenyl-N-acetyl-beta-d-glucosaminide and p-nitrophenyl-N-acetyl-beta-d-galactosaminide. The ratio of activity for hydrolysis of the two substrates is pH dependent. The K(m) value for the two substrates and pH optima of the isozymes are comparable to beta-NAHAs from other plant sources.

  16. The change of transforming growth factor {beta} 1 (TGF- {beta} 1) expression by melatonin in irradiated lung

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Seong Soon; Choi, Ihl Bohng [College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)


    The changed expressions of TGF- {beta} 1, as a key cytokine in the fibrotic process, due to melatonin with potent antioxidative effects, were investigated in the irradiated lung using fibrosis-sensitive C57BL/6 mice. Female C57BL/6 mice were divided into control irradiation-only, and melatonin (300 mg/kg i.p. 1 hr before irradiation) pretreatment groups. The thoraces of the mice were irradiated with a single dose of 12 Gy. The mRNA expressions of TGF-{beta} 1 in the lung tissue 2 and 4 weeks after irradiation were quantified using semiquantitive RT-PCR, and the cellular origin and expression levels of TGF- {beta} 1 protein were identified using immunohistochemical staining. The relative mRNA expression levels in the irradiation-only and melatonin pretreatment group 2 and 4 weeks after irradiation were 1.92- and 1.80-fold ({rho} = 0.064) and 2.38- and 1.94-fold ({rho} = 0.004) increased, respectively compared to those in the control group. Increased expressions of TGF- {beta} 1 protein were prominently detected in regions of histopathological radiation injury, with alveolar macrophages and septal epithelial cells serving as important sources of TGF- {beta} 1 expression. At 2 and 4 weeks after irradiation, the expression levels of protein were 15.8% vs. 16.9% ({rho} = 0.565) and 36.1% vs. 25.7% ({rho} = 0.009), respectively. The mRNA and protein expressions of TGF- {beta} 1 in the lung tissue following thoracic irradiation with 12 Gy were significantly decreased by melatonin pretreatment at 4 weeks. These results indicate that melatonin may have a possible application as an antifibrotic agent in radiation-induced lung injury.

  17. Performance of a parallel plate ionization chamber in beta radiation dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, Patricia L.; Caldas, Linda V.E., E-mail: patrilan@ipen.b, E-mail: lcaldas@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)


    A homemade parallel plate ionization chamber with graphite collecting electrode, and developed for use in mammography beams, was tested in relation to its usefulness in beta radiation dosimetry at the Calibration Laboratory of IPEN. Characterization tests of this ionization chamber were performed, using the Sr-90 + Y-90, Kr-85 and Pm-147 sources of a beta secondary standard system. The results of saturation, leakage current, stabilization time, response stability, linearity, angular dependence, and calibration coefficients are within the recommended limits of international recommendations that indicate that this chamber may be used for beta radiation dosimetry. (author)

  18. beta (+)-Thalassaemia in the Po river delta region (northern Italy): genotype and beta globin synthesis.


    del Senno, L; Pirastu, M; Barbieri, R.; De Bernardi, F.; Buzzoni, D; Marchetti, G.; Perrotta, C; Vullo, C; Kan, Y W; Conconi, F


    Six beta(+)-thalassaemic patients from the Po river delta region have been studied. Using synthetic oligonucleotides as specific hybridisation probes, the beta(+) IVS I mutation (G----A at position 108) was demonstrated. This lesion and the enzyme polymorphism pattern in the subjects examined are the same as have been described for other Mediterranean beta(+)-thalassaemias. Antenatal diagnosis through DNA analysis of beta(+)-thalassaemia is therefore possible. The production of beta globin in...

  19. The Mechanism of $\\beta$-Delayed Two-Proton Emission

    CERN Multimedia


    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 ...

  20. Specific Triazine Herbicides Induce Amyloid-beta(42) Production

    NARCIS (Netherlands)

    Portelius, Erik; Durieu, Emilie; Bodin, Marion; Cam, Morgane; Pannee, Josef; Leuxe, Charlotte; Mabondzo, Aloise; Oumata, Nassima; Galons, Herve; Lee, Jung Yeol; Chang, Young-Tae; Stuber, Kathrin; Koch, Philipp; Fontaine, Gaelle; Potier, Marie-Claude; Manousopoulou, Antigoni; Garbis, Spiros D.; Covaci, Adrian; Van Dam, Debby; De Deyn, Peter; Karg, Frank; Flajolet, Marc; Omori, Chiori; Hata, Saori; Suzuki, Toshiharu; Blennow, Kaj; Zetterberg, Henrik; Meijer, Laurent


    Proteolytic cleavage of the amyloid-beta protein precursor (A beta PP) ecretases leads to extracellular release of amyloid-beta (A beta) peptides. Increased production of A beta(42) over A beta(40) and aggregation into oligomers and plaques constitute an Alzheimer's disease (AD) hallmark. Identifyin

  1. Future double beta decay experiments

    Energy Technology Data Exchange (ETDEWEB)

    Piquemal, F. [Laboratoire Souterrain de Modane, Modane (France); Centre d' Etudes Nucleaire, Bordeaux-Gradignan (France)


    The search of neutrinoless double beta decay is very challenging because of the expected half-life of the process and the backgrounds from the natural radioactivity. Many projects exist to try to reach a sensitivity of ∼50 meV on the effective neutrino mass corresponding to a mass of isotopes of ∼100 kg. In this article some of the futur projects are presented.

  2. Myokardinfarkt und Beta-Blocker

    Directory of Open Access Journals (Sweden)

    Stühlinger H-G


    Full Text Available Im Rahmen eines akuten koronaren Syndroms (akuter Herzinfarkt, Angina pectoris kommt es, aufgrund eines Ungleichgewichtes zwischen Angebot und Bedarf, zu einem akuten Mangel an Sauerstoff im Herzmuskel. Ursache ist eine reduzierte Sauerstoffzufuhr durch verengte bzw. verschlossene Gefäße. Bis zur Behebung der Ursache vergehen oft mehrere Stunden. In dieser Phase muß - durch Verminderung des Sauerstoffbedarfs im Herzmuskel - eine Verlangsamung der Nekroseentwicklung erreicht werden. Das Ausmaß der Nekrose wird reduziert, somit die für die Langzeitprognose wichtige Linksventrikelfunktion verbessert. Eine Verminderung des Sauerstoffbedarfs erreicht man durch kontrollierte Frequenzsenkung mittels intravenöser Beta-Blockade. In optimaler Weise wird diese Methode durch die Anwendung eines kardioselektiven Beta-Blockers mit kurzer Halbwertszeit durchgeführt. Beta-Blocker haben nicht nur auf die Nekroseentwicklung, sondern auch auf die Inzidenz von Rhythmusstörungen - besonders in der Akutphase - Auswirkungen. Vor allem die mit dieser therapeutischen Maßnahme verbundene Reduktion von Kammerflimmern ist von großer Bedeutung.

  3. Role of ROS-mediated TGF beta activation in laser photobiomodulation (United States)

    Arany, Praveen R.; Chen, Aaron Chih-Hao; Hunt, Tristan; Mooney, David J.; Hamblin, Michael


    The ability of laser light to modulate specific biological processes has been well documented but the precise mechanism mediating these photobiological interactions remains an area of intense investigation. We recently published the results of our clinical trial with 30 patients in an oral tooth-extraction wound healing model using a 904nm GaAs laser (Oralaser 1010, Oralia, Konstnaz, Germany), assessing healing parameters using routine histopathology and immunostaining (Arany et al Wound Rep Regen 2007, 15, 866). We observed a better organized healing response in laser irradiated oral tissues that correlated with an increased expression of TGF-beta1 immediately post laser irradiation. Our data suggested the source of latent TGF-beta1 might be from the degranulating platelets in the serum, an abundant source of in vivo latent TGF-beta, in the freshly wounded tissues. Further, we also demonstrated the ability of the low power near-infrared laser irradiation to activate the latent TGF-beta complexes in vitro at varying fluences from 10sec (0.1 J/cm2) to 600secs (6 J/cm2). Using serum we observed two isoforms, namely TGF-beta1 and TGF-beta3, were capable of being activated by laser irradiation using an isoform-specific ELISA and a reporter based (p3TP) assay system. We are presently pursuing the precise photomolecular mechanisms focusing on potential chromophores, wavelength and fluence parameters affecting the Latent TGF-beta activation process in serum. As ROS mediated TGF-beta activation has been previously demonstrated and we are also exploring the role of Laser generated-ROS in this activation process. In summary, we present evidence of a potential molecular mechanism for laser photobiomodulation in its ability to activate latent TGF-beta complexes.

  4. $\\beta$-particle energy-summing correction for $\\beta$-delayed proton emission measurements

    CERN Document Server

    Meisel, Z; Crawford, H L; Cyburt, R H; Grinyer, G F; Langer, C; Montes, F; Schatz, H; Smith, K


    A common approach to studying $\\beta$-delayed proton emission is to measure the energy of the emitted proton and corresponding nuclear recoil in a double-sided silicon-strip detector (DSSD) after implanting the $\\beta$-delayed proton emitting ($\\beta$p) nucleus. However, in order to extract the proton-decay energy, the measured energy must be corrected for the additional energy implanted in the DSSD by the $\\beta$-particle emitted from the $\\beta$p nucleus, an effect referred to here as $\\beta$-summing. We present an approach to determine an accurate correction for $\\beta$-summing. Our method relies on the determination of the mean implantation depth of the $\\beta$p nucleus within the DSSD by analyzing the shape of the total (proton + recoil + $\\beta$) decay energy distribution shape. We validate this approach with other mean implantation depth measurement techniques that take advantage of energy deposition within DSSDs upstream and downstream of the implantation DSSD.

  5. Alpha and beta dose gradients in tooth enamel

    Energy Technology Data Exchange (ETDEWEB)

    Brennan, B.J. E-mail:; Prestwich, W.V.; Rink, W.J.; Marsh, R.E.; Schwarcz, H.P


    New results describing gradients in effective alpha and beta doses within a layer of tooth enamel in planar geometry are presented. The alpha (track) dose to an enamel layer is calculated using an algorithm similar to that of Aitken (Aitken, M.J., 1987. Alpha dose to a thin layer. Ancient TL 5, 1-3.). The code for ROSY version 1.4 incorporates this algorithm. The approach allows for variation of the alpha track dose near the edges of the enamel, and we describe the gradient of the alpha track dose within 40 {mu}m of each edge of the enamel for natural sources. In ESR or luminescence dating of naturally thin layers, for which stripping of the surface layer containing the alpha dose gradients may not be feasible, age estimates may change by as much as 5-10% when the detailed alpha dose calculation is included. Modern Monte Carlo-based results for the variation of beta dose for depths up to 2 mm are compared with ROSY results. For external irradiation by different sources, the attenuation of the ROSY dose estimate with depth is usually less rapid than that of the Monte Carlo-based estimate. The ROSY estimate of average beta dose to a layer in this case is between 5 and 18% higher than the Monte Carlo estimate.

  6. Precision Study of the $\\beta$-decay of $^{62}$Ga

    CERN Multimedia


    It is proposed to perform a precision study of the $\\beta$-decay of $\\,^{62}$Ga taking advantage of recent developments of the ISOLDE Laser Ion Source. The goal is to eventually extend the high-precision knowledge of superallowed $\\beta$-decays beyond the nine decays that presently are used for extracting the V$_{ud}$ quark mixing matrix element of the CKM matrix. The scientific motivations are the current deviation of more than 2$\\sigma$ of the unitary condition of this matrix, which could be an indication of non-standard-model physics, and a test of the theoretical corrections applied to the experimental data. The experiment will utilise the Total Absorption $\\gamma$-ray (TAG) spectrometer in order to determine weak branchings to excited states in $^{62}$Zn and the ISOLDE spectroscopy station to perform half-life measurements and detailed spectroscopy of this nucleus.

  7. Dynamic Hysteresis Probes High-{\\beta} Nanolaser Emission Regimes

    CERN Document Server

    Pan, Si Hui; Amili, Abdelkrim El; Vallini, Felipe; Fainman, Yeshaiahu


    The quest for an integrated light source that promises high energy efficiency and fast modulation for high-performance photonic circuits has led to the development of room-temperature telecom-wavelength nanoscale laser with high spontaneous emission factors, \\beta. The coherence characterization of this type of lasers is inherently difficult with the conventional measurement of output light intensity versus input pump intensity due to the diminishing kink in the measurement curve. We demonstrate the transition from chaotic to coherent emission of a high-{\\beta} pulse-pump metallo-dielectric nanolaser can be determined by examining the width of a second order intensity correlation peak, which shrinks below and broadens above threshold. Photon fluctuation study, first one ever reported for this type of nanolaser, confirms the validity of this measurement technique. Additionally, we show that the width variation above threshold results from the delayed threshold phenomenon, providing the first indirect observati...

  8. Field tests of a tissue-equivalent beta survey meter

    Energy Technology Data Exchange (ETDEWEB)

    Martz, D.E.; Johnson, L.O.; Rich, B.L.; Daniel, S.H.


    A tissue-equivalent survey meter for monitoring the (dD/dt)(0.07) and (dD/dt)(10) dose rates produced by betas and photons has been designed and tested. The very thin tissue-equivalent plastic scintillator closely simulates the critical skin tissue layer between 4 -2/ and 9 -2/. The meter is calibrated to read the (dD/dt)(0.07) dose rate directly, and the (dD/dt)(10) dose rate behind a filter. Laboratory measurements of calibrated sources and field tests have demonstrated tissue-equivalent response of the survey meter to betas between 70 keV and 2500 keV and to photons with energies greater than about 30 keV.

  9. Beta Function Measurement in the Tevatron Using Quadrupole Gradient Modulation

    CERN Document Server

    Jansson, Andreas; Volk, James T


    Early in Run2, there was an effort to compare the different emittance measurements in the Tevatron (flying wires and synchtotron light) and understand the origin of the observed differences. To measure the beta function at a few key locations near the instruments, air-core quadrupoles were installed. By modulating the gradient of these magents and measuring the effect on the tune, the lattice parameters can be extracted. Initially, the results seem to disagree with with other methods. At the time, the lattice was strongly coupled due to a skew component in the main dipoles, caused by sagging of the cryostat. After a large fraction of the superconducting magnets were shimmed to remove a strong skew quadrupole component, the results now agree with expectations, confirming that the beta function is not the major error source of discrepancy in the emittance measurement.

  10. Transradial coronary brachytherapy with the Novoste Beta-Rail system. (United States)

    Bertrand, Olivier F; De Larochellière, Robert; Gleeton, Onil; Plante, Sylvain; Tessier, Michel; Guimond, Jean


    We report our initial experience in 10 consecutive patients who underwent transradial coronary brachytherapy for in-stent restenosis using a 90Sr/Y source and the Novoste Beta-Rail system. In all patients, procedures were successfully completed using a right transradial approach. We performed the procedures with the Beta-Rail catheter using 7 Fr (Zuma II, Medtronic, MN; n = 5) or 8 Fr (Cordis, Miami, FL; n = 5) guiding catheters. All lesions were successfully dilated and no additional stent was inserted. We used a 40 mm source (n = 3) or a 60 mm source (n = 7) with manual stepping in four cases. In three cases, we did one stepping, and in one case, we did three steppings. The mean dwell time was 195 plus minus 44 sec. The mean delivered dose was 23 +/- 3 Gy at 2 mm distance from the source. No radiation treatment was interrupted. Mean fluoroscopy time was 26 +/- 13 min. Procedural success was achieved in all patients. Three patients had mild CK elevations (< 3 times upper normal limit). All patients were pretreated with clopidogrel (300 mg) and combined treatment with aspirin + clopidogrel is to be continued for at least 1 year. Clinical follow-up up to 3 months has not yielded any complication and all patients have remained free from angina.

  11. Optical Spectroscopy of Four Young Radio Sources

    CERN Document Server

    Fan, Xu-Liang; Hu, Chen; Wang, Jian-Guo


    We report the optical spectroscopy of four young radio sources which are observed with the Lijiang 2.4m telescope. The Eddington ratios of these sources are similar with those of narrow-line Seyfert 1 galaxies (NLS1s). Their Fe {\\sc ii} emission is strong while [O {\\sc iii}] strength is weak. These results confirm the NLS1 features of young radio sources, except that the width of broad H$\\beta$ of young radio sources is larger than that of NLS1s. We thus suggest that the young radio sources are the high black hole mass counterparts of steep-spectrum radio-loud NLS1s. In addition, the broad H$\\beta$ component of \\astrobj{4C 12.50} is the blue wing of the narrow component, but not from the broad line region.

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

    Directory of Open Access Journals (Sweden)

    Hamid Arazi


    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.

  13. Ser2 is the autophosphorylation site in the beta subunit from bicistronically expressed human casein kinase-2 and from native rat liver casein kinase-2 beta

    DEFF Research Database (Denmark)

    Boldyreff, B; James, P; Staudenmann, W;


    Human casein kinase-2 (CK-2) subunits alpha and beta were bicistronically expressed in bacteria. The recombinant holoenzyme shared all investigated properties with the native CK-2 from mammalian sources (rat liver, Krebs II mouse ascites tumour cells). Contrary to recombinant human CK-2 produced...

  14. Asymmetrically acting lycopene beta-cyclases (CrtLm) from non-photosynthetic bacteria. (United States)

    Tao, L; Picataggio, S; Rouvière, P E; Cheng, Q


    Carotenoids have important functions in photosynthesis, nutrition, and protection against oxidative damage. Some natural carotenoids are asymmetrical molecules that are difficult to produce chemically. Biological production of carotenoids using specific enzymes is a potential alternative to extraction from natural sources. Here we report the isolation of lycopene beta-cyclases that selectively cyclize only one end of lycopene or neurosporene. The crtLm genes encoding the asymmetrically acting lycopene beta-cyclases were isolated from non-photosynthetic bacteria that produced monocyclic carotenoids. Co-expression of these crtLm genes with the crtEIB genes from Pantoea stewartii (responsible for lycopene synthesis) resulted in the production of monocyclic gamma-carotene in Escherichia coli. The asymmetric cyclization activity of CrtLm could be inhibited by the lycopene beta-cyclase inhibitor 2-(4-chlorophenylthio)-triethylamine (CPTA). Phylogenetic analysis suggested that bacterial CrtL-type lycopene beta-cyclases might represent an evolutionary link between the common bacterial CrtY-type of lycopene beta-cyclases and plant lycopene beta- and epsilon-cyclases. These lycopene beta-cyclases may be used for efficient production of high-value asymmetrically cyclized carotenoids.

  15. Neuronal injury induces the release of pro-interleukin-1beta from activated microglia in vitro. (United States)

    Wang, Penglian; Rothwell, Nancy J; Pinteaux, Emmanuel; Brough, David


    Microglia activated after brain injury, are a major source of the pro-inflammatory cytokine interleukin-1 (IL-1), which is known to further exacerbate damage. However, the mechanisms that control IL-1 release in acute neuronal injury are unknown and the purpose of this study was to test the hypothesis that neuronal injury induces IL-1beta release from microglial cells. Here we report that lipopolysaccharide (LPS)-activated rat microglia co-cultured with healthy rat neurons express pro-IL-1beta, which in the absence of cell death accumulates in the cells. Treatment of co-cultures with the excitotoxin N-methyl-D-aspartate (NMDA) induced neuronal cell death leading to the appearance of pro-IL-1beta in the culture supernatant. This effect was reversed by the NMDA receptor antagonist MK-801, and was neuron-dependent, since NMDA had no effect on cell death or pro-IL-1beta release in mixed glial cell cultures. In addition, we show that pro-IL-1beta release from LPS-treated mixed glia or LPS-treated microglia is significantly reduced in the presence of conditioned medium from healthy co-cultures or neuronal cultures respectively. These results demonstrate that injured neurons promote the release of pro-IL-1beta from microglia, possibly by regulating microglial cell viability, and suggest an important alternative mechanism of IL-1beta release that occurs in response to neuronal injury.

  16. Abstraction Mechanisms in the BETA Programming Language

    DEFF Research Database (Denmark)

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


    ]) --- covering both data, procedural and control abstractions, substituting constructs like class, procedure, function and type. Correspondingly objects, procedure activation records and variables are all regarded as special cases of the basic building block of program executions: the entity. A pattern thus......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...

  17. In vivo evaluation of expression of TGF{beta}1 in the irradiated heart; Expressao da proteina TGF{beta}1 em coracao irradiado in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Affonso Junior, Renato Jose [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil). Escola Paulista de Medicina. Dept. Diagnostico por Imagem; Oshima, Celina Tizuko Fujiyama; Silva, Maria Regina Regis [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil). Escola Paulista de Medicina. Setor de Anatomia Patologica; Kimura, Edna Teruko [Sao Paulo Univ., SP (Brazil). Inst. de Ciencias Biomedicas. Dept. de Histologia; Egami, Mizue Imoto [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil). Escola Paulista de Medicina. Dept. de Morfologia; Segreto, Roberto Araujo; Segreto, Helena Regina Comodo [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil). Escola Paulista de Medicina. Setor de Radioterapia]. E-mail:


    The objectives of this study were to assess the latent and active TGF{beta}1 localization in the heart, to evaluate whether or not radiation induces latent TGF{beta}1 activation, and to study the distribution of collagen fibers in the irradiated heart. Thirty-two C 57 BL mice were randomly assigned in two groups: GI (non irradiated animals) and GII (irradiated animals). The mice from G II received a single whole-body radiation dose of 7 Gy, using a {sup 60}Co source at a dose rate of 0.97 Gy/min. The animals were sacrificed by cervical dislocation at 1, 14, 30 and 90 days after irradiation. The irradiated hearts showed: nuclear changes and muscle cells with decreased striations; significant increase in the collagen deposition 90 days after irradiation; latent TGF{beta}1 activation in the cardio myocytes and connective tissue cells after irradiation. Our results show the importance of TGF{beta}1 protein in the process of radiation-induced heart fibrosis and suggest that cardio myocytes and connective cells may play a role in this mechanism acting as cellular sources of active TGF{beta}1. (author)

  18. Production and some characteristics of beta-glucosidase in Diaporthe (Phomopsis) helianthi. (United States)

    Pericin, D; Jarak, M


    Diaporthe (Phomopsis) helianthi Munt.-Cvet. et al. is an important phytopathogenic fungus which causes stem canker of sunflower. When grown in submerged cultures in the presence of milled wheat chaff as a carbon source this phytopathogen produced extracellular and intracellular beta-glucosidases. The optimum pH of these enzymes was 4.8. The temperature of crude intracellular beta-glucosidase activity was at 60 degrees C, whereas the optimum activity of crude extracellular beta-glucosidase was observed in a wide range of temperature between 40 and 70 degrees C. Although, extracellular and intracellular beta-glucosidase activities had identical pH and similar temperature optima, the thermal stability of the intracellular enzyme was significantly higher.

  19. Optimization of plastic scintillator thicknesses for online beta/gamma detection

    Directory of Open Access Journals (Sweden)

    Pourtangestani K.


    Full Text Available For efficient beta detection in a mixed beta gamma field, Monte Carlo simulation models have been built to optimize the thickness of a plastic scintillator, used in a whole body monitor. The simulation has been performed using the MCNP/X code for different thicknesses of plastic scintillator from 150 μm to 600 μm. The relationship between the thickness of the scintillator and the efficiency of the detector has been analyzed. For 150 μm thickness, an experimental investigation has been conducted with different beta sources at different positions on the scintillator and the counting efficiency of the unit has been measured. Evaluated data along with experimental ones have been discussed. A thickness of 300 μm to 500 μm has been found to be the optimum thickness for high efficiency beta detection in the presence of low energy gamma-rays.

  20. Is Transforming Stem Cells to Pancreatic Beta Cells Still the Holy Grail for Type 2 Diabetes? (United States)

    Kahraman, Sevim; Okawa, Erin R; Kulkarni, Rohit N


    Diabetes is a progressive disease affecting millions of people worldwide. There are several medications and treatment options to improve the life quality of people with diabetes. One of the strategies for the treatment of diabetes could be the use of human pluripotent stem cells or induced pluripotent stem cells. The recent advances in differentiation of stem cells into insulin-secreting beta-like cells in vitro make the transplantation of the stem cell-derived beta-like cells an attractive approach for treatment of type 1 and type 2 diabetes. While stem cell-derived beta-like cells provide an unlimited cell source for beta cell replacement therapies, these cells can also be used as a platform for drug screening or modeling diseases.

  1. Search for non Standard Model physics in nuclear-$\\beta$ decay with the WITCH experiment

    CERN Document Server

    Coeck, Sam

    In this work the WITCH experiment, which primarily aims for precision measurements of the beta-neutrino-angular correlation coefficient, is presented in detail. First a theoretical description of the beta-decay process is presented and it was shown how measurements of correlation coefficients can reveal the exact nature of the weak interaction. Although many experiments have already been conducted in this field, there is still considerable room for additional phenomena that are not included in the Standard Model. At WITCH the beta-neutrino-angular correlation coefficient will be obtained from precision measurements of the energy spectrum of the nuclei that recoil after beta-decay, thus avoiding the need to observe the neutrino. To enable a measurement of the recoiling ions, the setup uses a combination of two electromagnetic Penning traps and a retardation spectrometer. This allows one to construct the scattering free radioactive source that is needed as the recoiling ions have only a very small kinetic energ...

  2. Biodisponibilidade do beta-caroteno da folha desidratada de mandioca (Manihot esculenta Crantz Bioavailability of beta-carotene in dehydrated cassava leaves (manihot esculenta Crantz

    Directory of Open Access Journals (Sweden)

    Claudia Isabel Ortega-Flores


    Full Text Available Com o objetivo de verificar a biodisponibilidade do beta-caroteno da folha de mandioca (Manihot esculenta Crantz foi realizado um ensaio biológico baseado no modelo de esgotamento das reservas hepáticas de vitamina A em ratos. Um grupo de ratos depletados de vitamina A hepática recebeu folha desidratada de mandioca como fonte beta-caroteno durante 25 dias, e foram comparados com um grupo que recebeu ração com vitamina A, outro grupo com ração sem vitamina A e um último grupo com beta-caroteno. O grupo Zero foi constituído de 8 animais que receberam durante 15 dias ração à base de caseína, deficiente de vitamina A. Ao final do experimento todos os animais foram sacrificados e seus fígados e plasmas analisados por Cromatografia Líquida de Alta Eficiência (CLAE, sendo verificado que a biodisponibilidade do beta-caroteno da folha desidratada de mandioca foi baixa.The biological availability of beta-carotene in cassava leaves (Manihot esculenta Crantz, was verified by means of an assay based on the hepatic depletion of vitamin A reserves model in rats. Rats depleted of hepatic vitamin A received dehydrated cassava leaves as beta-carotene source for 25 days and were compared to groups that received diets with vitamin A, beta-carotene and without vitamin A. The Zero group was formed of 8 animals that received a diet based on casein, lacking vitamin A, during 15 days. At the end of the experiment, all animals were killed and their livers, serum and feces were analyzed by high performance liquid chromatography (HPLC, and it was verified that the bioavailability of beta-carotene of dehydrated cassava leaves was lower.

  3. Milk Intolerance, Beta-Casein and Lactose. (United States)

    Pal, Sebely; Woodford, Keith; Kukuljan, Sonja; Ho, Suleen


    True lactose intolerance (symptoms stemming from lactose malabsorption) is less common than is widely perceived, and should be viewed as just one potential cause of cows' milk intolerance. There is increasing evidence that A1 beta-casein, a protein produced by a major proportion of European-origin cattle but not purebred Asian or African cattle, is also associated with cows' milk intolerance. In humans, digestion of bovine A1 beta-casein, but not the alternative A2 beta-casein, releases beta-casomorphin-7, which activates μ-opioid receptors expressed throughout the gastrointestinal tract and body. Studies in rodents show that milk containing A1 beta-casein significantly increases gastrointestinal transit time, production of dipeptidyl peptidase-4 and the inflammatory marker myeloperoxidase compared with milk containing A2 beta-casein. Co-administration of the opioid receptor antagonist naloxone blocks the myeloperoxidase and gastrointestinal motility effects, indicating opioid signaling pathway involvement. In humans, a double-blind, randomized cross-over study showed that participants consuming A1 beta-casein type cows' milk experienced statistically significantly higher Bristol stool values compared with those receiving A2 beta-casein milk. Additionally, a statistically significant positive association between abdominal pain and stool consistency was observed when participants consumed the A1 but not the A2 diet. Further studies of the role of A1 beta-casein in milk intolerance are needed.

  4. Sawtooth crashes at high beta on JET

    Energy Technology Data Exchange (ETDEWEB)

    Alper, B.; Huysmans, G.T.A.; Sips, A.C.C. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Nave, M.F.F. [Universidade Tecnica, Lisbon (Portugal). Inst. Superior Tecnico


    The sawtooth crashes on JET display features which depend on beta. The main observation is a transient bulging of flux surfaces (duration inferior to 30 microsec.), which is predominantly on the low field side and extends to larger radii as beta increases. This phenomenon reaches the plasma boundary when beta{sub N} exceeds 0.5 and in these cases is followed by an ELM within 50 microsec. These sawtooth/ELM events limit plasma performance. Modelling of mode coupling shows qualitative agreement between observations of the structure of the sawtooth precursor and the calculated internal kink mode at high beta. (authors). 6 refs., 5 figs.

  5. Milk Intolerance, Beta-Casein and Lactose

    Directory of Open Access Journals (Sweden)

    Sebely Pal


    Full Text Available True lactose intolerance (symptoms stemming from lactose malabsorption is less common than is widely perceived, and should be viewed as just one potential cause of cows’ milk intolerance. There is increasing evidence that A1 beta-casein, a protein produced by a major proportion of European-origin cattle but not purebred Asian or African cattle, is also associated with cows’ milk intolerance. In humans, digestion of bovine A1 beta-casein, but not the alternative A2 beta-casein, releases beta-casomorphin-7, which activates μ-opioid receptors expressed throughout the gastrointestinal tract and body. Studies in rodents show that milk containing A1 beta-casein significantly increases gastrointestinal transit time, production of dipeptidyl peptidase-4 and the inflammatory marker myeloperoxidase compared with milk containing A2 beta-casein. Co-administration of the opioid receptor antagonist naloxone blocks the myeloperoxidase and gastrointestinal motility effects, indicating opioid signaling pathway involvement. In humans, a double-blind, randomized cross-over study showed that participants consuming A1 beta-casein type cows’ milk experienced statistically significantly higher Bristol stool values compared with those receiving A2 beta-casein milk. Additionally, a statistically significant positive association between abdominal pain and stool consistency was observed when participants consumed the A1 but not the A2 diet. Further studies of the role of A1 beta-casein in milk intolerance are needed.

  6. Challenges in Double Beta Decay

    Directory of Open Access Journals (Sweden)

    Oliviero Cremonesi


    Full Text Available In the past ten years, neutrino oscillation experiments have provided the incontrovertible evidence that neutrinos mix and have finite masses. These results represent the strongest demonstration that the electroweak Standard Model is incomplete and that new Physics beyond it must exist. In this scenario, a unique role is played by the Neutrinoless Double Beta Decay searches which can probe lepton number conservation and investigate the Dirac/Majorana nature of the neutrinos and their absolute mass scale (hierarchy problem with unprecedented sensitivity. Today Neutrinoless Double Beta Decay faces a new era where large-scale experiments with a sensitivity approaching the so-called degenerate-hierarchy region are nearly ready to start and where the challenge for the next future is the construction of detectors characterized by a tonne-scale size and an incredibly low background. A number of new proposed projects took up this challenge. These are based either on large expansions of the present experiments or on new ideas to improve the technical performance and/or reduce the background contributions. In this paper, a review of the most relevant ongoing experiments is given. The most relevant parameters contributing to the experimental sensitivity are discussed and a critical comparison of the future projects is proposed.

  7. The pharmacokinetics of beta-cyclodextrin and hydroxypropyl-beta-cyclodextrin in the rat

    NARCIS (Netherlands)

    Frijlink, H W; Visser, J; Hefting, N R; Oosting, R; Meijer, D K; Lerk, C F


    Hydroxypropyl-beta-cyclodextrin was analyzed by HPLC using postcolumn complexation with phenolphthalein and negative colorimetric detection, with a detection limit of 20 micrograms/ml. The pharmacokinetics of beta-cyclodextrin and of hydroxypropyl-beta-cyclodextrin were studied after intravenous adm

  8. The impact of beta-elemene on beta-tubulin of human hepatoma hepg2 cells

    Institute of Scientific and Technical Information of China (English)

    Yuqiu Mao; Liying Ban; Jielin Zhang; Li Hou; Xiaonan Cui


    Objective:The aim of this study was to investigate the impact of beta-elemene injection on the growth and beta-tubulin of human hepatocarcinoma HepG2 cells. Methods:cellproliferation was assessed by MTT assay. cellcycle distribution was detected by flow cytometry (FCM). The mRNA expression of beta-tubulin was measured by RT-PCR. West-ern blot analysis was used to determine protein expression of beta-tubulin and the polymerization of beta-tubulin. Results:Beta-elemene injection inhibited HepG2 cells proliferation in a dose-and time-dependent manner;FCM analysis indicated beta-elemene injection induced cellcycle arrested at S phase. RT-PCR and western-blot analysis showed that beta-elemene injection down-regulated beta-tubulin expression at both mRNA and protein levels, presenting a dose-dependent manner. Moreover, beta-elemene injection reduced the polymerization of microtubules in a dose-dependent manner. Conclusion:Beta-elemene injection can inhibit the proliferation of hepatoma HepG2 cells, the mechanism might be partly related to the down-regulation of beta-tubulin and inhibition of microtubular polymerization.

  9. Expressions of GSK-3beta, Beta-Catenin and PPAR-Gamma in Medulloblastoma

    Institute of Scientific and Technical Information of China (English)

    Xiong Zhang; Lu Si; Yu Li; Can Mi


    Objective: To investigate the expressions of GSK-3beta, Beta-catenin and PPAR-gamma, and their relationship in medulloblastoma, and to explore their value in clinic application.Methods: Immunohistochemical staining with SP method was conducted to determine the expressions of GSK-3beta, Beta-catenin and PPAR-gamma in 48 cases of medulloblastoma and 10 normal cerebellar tissues.Results: The rate of abnormal expressions of beta-catenin and PPAR-gamma in MB was higher than that in normal. Conversely, GSK-3beta in MB was lower than that in the normal (P<0.05). Furthermore, in medulloblastoma, beta-catenin and GSK-3beta showed a negative correlation, PPAR-gamma and beta-catenin had a positive correlation.Conclusion: Abnormal expression of beta-catenin plays a crucial role in the development of medulloblastoma. Meanwhile, PPAR-gamma and GSK-3beta which are tightly related with beta-catenin are both involved in the genesis and development of medulloblastoma.

  10. Radiation-induced polymerization of {beta}(+)-pinene and synthesis of optically active {beta}(+)/{beta}(-)pinene polymers and copolymers

    Energy Technology Data Exchange (ETDEWEB)

    Cataldo, Franco, E-mail: franco.cataldo@fastwebnet.i [Lupi Chemical Research, Via Casilina 1626/A, 00133 Rome (Italy); Lilla, Edo; Ursini, Ornella [Institute of Chemical Methodologies, CNR, Via Salaria Km. 29300, Monterotondo Stazione 00016, Rome (Italy)


    Poly-{beta}(+)-pinene (pB(+)p) was synthesized with {gamma} irradiation of the monomer {beta}(+)-pinene in bulk under vacuum at 1181 kGy. Also scalemic mixtures of {beta}(+)-pinene and {beta}(-)-pinene were irradiated at 1181 kGy to obtain synthetic copolymers of pB(+)/B(-)p. For comparison also {beta}(-)-pinene was converted into poly-{beta}(-)-pinene (pB(-)p) under the identical conditions adopted for its enantiomer. Furthermore pB(+)p and pB(-)p were also synthesized by thermal processing under the action of a chemical free radical initiator. The optical rotatory dispersion (ORD) of all pBp resins synthesized were accurately studied in the spectral range comprised between 375 and 625 nm and a curious asymmetry in the ORD of pB(+)p versus the ORD of pB(-)p is reported. Furthermore, it is shown that (+)-p-menth-1-ene and (-)-p-menth-1-ene are useful as a model compounds for the pBp resins and for the explanation of the amplification of the optical activity of the {beta}(+)-pinene and {beta}(-)-pinene after their ring-opening polymerization to pB(+)p and pB(-)p. The pBp resins were studied also by FT-IR spectroscopy and by thermal analysis (TGA and DTG).

  11. 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


    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.

  12. Neutrinoless double beta decay and neutrino mass (United States)

    Vergados, J. D.; Ejiri, H.; Šimkovic, F.


    The observation of neutrinoless double beta decay (DBD) will have important consequences. First it will signal that lepton number is not conserved and the neutrinos are Majorana particles. Second, it represents our best hope for determining the absolute neutrino mass scale at the level of a few tens of meV. To achieve the last goal, however, certain hurdles have to be overcome involving particle, nuclear and experimental physics. Particle physics is important since it provides the mechanisms for neutrinoless DBD. In this review, we emphasize the light neutrino mass mechanism. Nuclear physics is important for extracting the useful information from the data. One must accurately evaluate the relevant nuclear matrix elements (NMEs), a formidable task. To this end, we review the recently developed sophisticated nuclear structure approaches, employing different methods and techniques of calculation. We also examine the question of quenching of the axial vector coupling constant, which may have important consequences on the size of the NMEs. From an experimental point of view it is challenging, since the life times are extremely long and one has to fight against formidable backgrounds. One needs large isotopically enriched sources and detectors with good energy resolution and very low background.

  13. Optimizing the greenfield Beta-beam

    CERN Document Server

    Agarwalla, Sanjib Kumar; Raychaudhuri, Amitava; Winter, Walter


    We perform a comprehensive and detailed comparison of the physics reach of Beta-beam experiments between two pairs of plausible source ions, (8B, 8Li) and (18Ne, 6He). We study the optimal choices for the baseline, boost factor, and luminosity. We take a 50 kton iron calorimeter, a la ICAL@INO, as the far detector. We follow two complementary approaches for our study: (i) Fixing the number of useful ion decays and boost factor of the beam, and optimizing for the sensitivity reach between the two pairs of ions as a function of the baseline. (ii) Matching the shape of the spectrum between the two pairs of ions, and studying the requirements for baseline, boost factor, and luminosity. We find that for each pair of ions there are two baselines with very good sensitivity reaches: a short baseline with $L [km]/ \\gamma \\simeq 2.6$ (8B+8Li) and $L [km]/\\gamma \\simeq 0.8$ (18Ne+6He), respectively, and a long ``magic'' baseline. For $\\gamma \\sim 500$, one would optimally use 6He and 18Ne at the short baseline for CP vi...

  14. Beta-glucosidase I variants with improved properties

    Energy Technology Data Exchange (ETDEWEB)

    Bott, Richard R.; Kaper, Thijs; Kelemen, Bradley; Goedegebuur, Frits; Hommes, Ronaldus Wilhelmus; Kralj, Slavko; Kruithof, Paulien; Nikolaev, Igor; Van Der Kley, Wilhelmus Antonious Hendricus; Van Lieshout, Johannes Franciscus Thomas; Van Stigt Thans, Sander


    The present disclosure is generally directed to enzymes and in particular beta-glucosidase variants. Also described are nucleic acids encoding beta-glucosidase variants, compositions comprising beta-glucosidase variants, methods of using beta-glucosidase variants, and methods of identifying additional useful beta-glucosidase variants.

  15. Signaling from beta1- and beta2-adrenergic receptors is defined by differential interactions with PDE4

    DEFF Research Database (Denmark)

    Richter, Wito; Day, Peter; Agrawal, Rani


    Beta1- and beta2-adrenergic receptors (betaARs) are highly homologous, yet they play clearly distinct roles in cardiac physiology and pathology. Myocyte contraction, for instance, is readily stimulated by beta1AR but not beta2AR signaling, and chronic stimulation of the two receptors has opposing...

  16. Localization of thymosin beta-4 in tumors

    DEFF Research Database (Denmark)

    Larsson, L. -I.; Holck, Susanne


    Overexpression of thymosin beta-4 has been linked to malignant progression but the localization of this polypeptide within tumors is incompletely known. We therefore examined breast cancers for thymosin beta-4 using immunofluorescence. Reactive cells were identified with monoclonal cell marker...... in the tumor microenvironment may modulate tumor behavior....

  17. Nebivolol : third-generation beta-blockade

    NARCIS (Netherlands)

    de Boer, Rudolf A.; Voors, Adriaan A.; van Veldhuisen, Dirk J.


    Nebivolol is a third generation beta-blocker. It is highly selective for the beta 1-adrenoceptor, and has additional nitric oxide-mediated vasodilating and antioxidant properties, along with a favourable metabolic profile. Nebivolol is well tolerated by patients with hypertension and heart failure.

  18. The beta subunit of casein kinase II

    DEFF Research Database (Denmark)

    Boldyreff, B; Piontek, K; Schmidt-Spaniol, I;


    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....

  19. Venus: Geology of Beta Regio rift system (United States)

    Nikishin, A. M.; Borozdin, V. K.; Bobina, N. N.


    Beta Regio is characterized by the existence of rift structures. We compiled new geologic maps of Beta Regio according to Magellan data. There are many large uplifted tesserae on beta upland. These tesserae are partly buried by younger volcanic cover. We can conclude, using these observations, that Beta upland formed mainly due to lithospheric tectonic uplifting and was only partly constructed by volcanism. Theia Mons is the center of the Beta rift system. Many rift belts are distributed radially to Theia Mons. Typical widths of rifts are 40-160 km. Rift valleys are structurally represented by crustal grabens or half-grabens. There are symmetrical and asymmetrical rifts. Many rifts have shoulder uplifts up to 0.5-1 km high and 40-60 km wide. Preliminary analysis for rift valley structural cross sections lead to the conclusion that rifts originated due to 5-10 percent crustal extension. Many rifts traverse Beta upland and spread to the surrounding lowlands. We can assume because of these data that Beta rift system has an active-passive origin. It formed due to regional tectonic lithospheric extension. Rifting was accelerated by upper-mantle hot spot origination under the center of passive extension (under the Beta Regio).

  20. Beta-agonists and animal welfare (United States)

    The use of beta-agonists in animal feed is a high profile topic within the U.S. as consumers and activist groups continue to question its safety. The only beta-agonist currently available for use in swine is ractopamine hydrochloride (RAC). This is available as Paylean™ (Elanco Animal Health – FDA a...

  1. High-$\\gamma$ Beta Beams within the LAGUNA design study

    CERN Document Server

    Orme, Christopher


    Within the LAGUNA design study, seven candidate sites are being assessed for their feasibility to host a next-generation, very large neutrino observatory. Such a detector will be expected to feature within a future European accelerator neutrino programme (Superbeam or Beta Beam), and hence the distance from CERN is of critical importance. In this article, the focus is a $^{18}$Ne and $^{6}$He Beta Beam sourced at CERN and directed towards a 50 kton Liquid Argon detector located at the LAGUNA sites: Slanic (L=1570 km) and Pyh\\"{a}salmi (L=2300 km). To improve sensitivity to the neutrino mass ordering, these baselines are then combined with a concurrent run with the same flux directed towards a large Water \\v{C}erenkov detector located at Canfranc (L=650 km). This degeneracy breaking combination is shown to provide comparable physics reach to the conservative Magic Baseline Beta Beam proposals. For $^{18}$Ne ions boosted to $\\gamma=570$ and $^{6}$He ions boosted to $\\gamma=350$, the correct mass ordering can be...

  2. Measurement of dose speed absorbed in depth imparted by sources external secondary patterns of beta radiation. Part 1 Measurement of dose speed absorbed in the surface of soft fabric for isotopes of {sup 90}Sr/{sup 90}Y, {sup 147}Pm and {sup 204}TI; Medicion de rapidez de dosis absorbida en profundidad impartida por fuentes patrones secundarios de radiacion beta externos. Parte 1. Medicion de rapidez de dosis absorbida en la superficie de tejido blando para isotopos de {sup 90}Sr/{sup 90}Y, {sup 147}Pm y {sup 204}TI

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez R, J.T. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)


    The dose speed was measured absorbed for depth zero, (superficial) in soft equivalent fabric, for the secondary pattern{sup s} four sources of beta radiation, (Nr. 86): {sup 90}Sr/{sup 90}Y, (1850 MBq and 74 MBq respectively); {sup 147}Pm, (518 MBq) and {sup 204}TI, (18.5 MBq). The measurement is carried out to different distances of source-detecting separation, (11.0, 30.0 and 50.0 cm for the source of 1850 MBq, 30.0 cm for that of 74 MBq; 11.00 cm for the source of {sup 147}Pmand to contact for all the sources); maintaining the radiation sheaf aligned the one axis of symmetry of the detector, ({alpha} 0 degrees). The detector employed was a extrapolation chambers of variable electrodes and electrode fixed collector, (30 mm of diameter). In accordance with the principle of Bragg-Gray the volume of the chambers is varied and they register the variations of the current of collected ionization, correcting until for a maximum of thirteen correction factors that take into account the deviation to the suppositions that it establishes this principle. The certain values of the speed of superficial absorbed dose are in the following intervals: {sup 90}Sr/{sup 90}Y, (1850 MBq, 0.0, 11.0, 30.0 and 50.0 cm): 43.164 mGy S-t, 0.544 mGy s-1 ,0.075 mGy s{sup -1} and 0.027 mGy s{sup -1}, respectively, with a Global Analysis of the order of 1.17%, 1.17%, 1.14% and 1.66%, K J; {sup 90}Sr / {sup 90}Y, (74 MBq, 0.0 and 30 cm): 1.536 mGy s{sup -1} and 0.002 mGy s{sup -1}, with Global Analysis of 1.19.0% and 5.22%, (K = 1) respectively, for the {sup 147}Pm, (0.0 and 11.0 in the interval of: 0.36 {mu}Gy s{sup -1} and 0.43 {mu}Gy s{sup -1}, with one Global Analysis of 1 .42% and 4.28%, (K = 1), respectively; and finally for the {sup 204}TI, (0.0 cm) in the interval of 0.10 {mu}Gy s{sup -1} with a Global Analysis of 1.27%. He calculates of the Global Analysis one carries out of agreement with those recommendations of the BIPM. In all the cases of source-detecting arrangement with

  3. The GERDA Neutrinoless Double Beta-Decay Experiment


    Majorovits, Bela; HULT MIKAEL; MARISSENS GERD; GASPARRO JOEL; Altmann, M; Bakalyarov, A.; Balata, M.; Barabanov, I.; Bauer, C; Bellotti, E.(Dipartimento di Fisica, Università Milano Bicocca, Milan, Italy); Belogurov, S.; Belyaev, S. T.(National Research Centre “Kurchatov Institute”, Moscow, Russia); BERNABE-HEIDER M.; Bettini, A.; Bezrukov, L.(Institute for Nuclear Research of the Russian Academy of Sciences, Moscow, Russia)


    Neutrinoless double beta-decay is the key process to gain understanding of the nature of neutrinos. The GErmanium Detector Array (GERDA) is designed to search for this decay of the isotope Ge-76. Germanium crystals enriched in Ge-76, acting as source and detector simultaneously, will be submerged directly into an ultra pure cooling medium that also serves as a radiation shield. This concept will allow for a reduction of the background by up to two orders of magnitudes with respect to earlier ...

  4. Values of the phase space factors for double beta decay

    Energy Technology Data Exchange (ETDEWEB)

    Stoica, Sabin, E-mail:; Mirea, Mihai [Horia Hulubei Foundation, 407, Atomistilor street, P.O. Box MG12, 077125 Magurele (Romania); Horia Hulubei National Institute of Physics and Nuclear Engineering, 30 Reactorului street, P.O. Box MG6, Magurele (Romania)


    We report an up-date list of the experimentally most interesting phase space factors for double beta decay (DBD). The electron/positron wave functions are obtained by solving the Dirac equations with a Coulomb potential derived from a realistic proton density distribution in nucleus and with inclusion of the finite nuclear size (FNS) and electron screening (ES) effects. We build up new numerical routines which allow us a good control of the accuracy of calculations. We found several notable differences as compared with previous results reported in literature and possible sources of these discrepancies are discussed.

  5. Search for $\\beta$-delayed protons from $^{11}$Be

    CERN Multimedia

    $\\beta$-delayed proton emission from $^{11}$Be will be a very rare process. It is believed to decay directly into continuum states. This would imply that it will be a sensitive probe of the halo structure of the one-neutron halo nucleus $^{11}$Be. We propose to improve existing (unpublished) limits on this decay mode by two orders of magnitude. Our earlier experience at ISOLDE indicates that the required intensity and purity of the source can be obtained. The branching ratio will be measured by counting the number of $^{10}$Be atoms produced via accelerator mass spectrometry.

  6. Beta-glucuronidase in physiology and disease. (United States)

    Basińska, Agnieszka; Floriańczyk, Bolesław


    beta-glucoronidase (EC is a lysosomal enzyme catylysing the decomposition of beta-D-glucoronides--compounds arising as a result of the combination of beta-D-glucoronic acid and a number of compounds both exo- and endogenous, containing hydroxylic, carboxylic, amine, imine or thiol groups. The most common test evaluating the activity of the enzyme is that using phenolphtalein glucoronide as a biosynthetic substrate. The freed aglycons are colorimetrically assayed. The activity of beta-glucoronidase increases in many pathological conditions: liver infammations, cirrhosis of the liver, inflammations of other organs, cholestatic jaundice, tuberculosis, sarcoidosis and also in neoplasms. Many authors point to beta-glucoronidase as a sensitive indicator signalling cell damage.

  7. Precision measurements in 20F beta decay (United States)

    Hughes, Maximilian; Naviliat-Cuncic, Oscar; Voytas, Paul; George, Elizabeth; Paulauskas, Stan; Huyan, Xueying


    Precision measurements of the shape of the beta particle energy spectrum provide a sensitive window to search for new interactions beyond the standard model. The decay of 20F offers an attractive system due to the simple decay scheme for a coincidence measurement. A beam of 20F ions, produced at the National Superconducting Cyclotron Laboratory, was implanted into a beta-detector. A gamma-ray detection system surrounded the beta detector to detect the beta-delayed gammas in coincidence to reduce the background. Preliminary analysis of these data focus on the half-life of 20F due to the statistical inconsistency of previous work. Monte Carlo simulations are ongoing to analyze the shape of the beta energy spectrum. Results of the analysis of the half-life will be presented. Supported by National Science Foundation Grant PHY-1102511.

  8. Ranking Beta Sheet Topologies of Proteins

    DEFF Research Database (Denmark)

    Fonseca, Rasmus; Helles, Glennie; Winter, Pawel


    One of the challenges of protein structure prediction is to identify long-range interactions between amino acids.  To reliably predict such interactions, we enumerate, score and rank all beta-topologies (partitions of beta-strands into sheets, orderings of strands within sheets and orientations...... of paired strands) of a given protein.  We show that the beta-topology corresponding to the native structure is, with high probability, among the top-ranked. Since full enumeration is very time-consuming, we also suggest a method to deal with proteins with many beta-strands. The results reported...... in this paper are highly relevant for ab initio protein structure prediction methods based on decoy generation. The top-ranked beta-topologies can be used to find initial conformations from which conformational searches can be started. They can also be used to filter decoys by removing those with poorly...

  9. The search for neutrinoless double beta decay

    CERN Document Server

    Gomez-Cadenas, J J; Mezzetto, M; Monrabal, F; Sorel, M


    In the last few years the search for neutrinoless double beta decay has evolved from being almost a marginal activity in neutrino physics to one of the highest priorities for understanding neutrinos and the origin of mass. There are two main reasons for this paradigm shift: the discovery of neutrino oscillations, which clearly established the existence of massive neutrinos; and the existence of an unconfirmed, but not refuted, claim of evidence for neutrinoless double decay in 76Ge. As a consequence, a new generation of experiments, employing different detection techniques and {\\beta}{\\beta} isotopes, is being actively promoted by experimental groups across the world. In addition, nuclear theorists are making remarkable progress in the calculation of the neutrinoless double beta decay nuclear matrix elements, thus eliminating a substantial part of the theoretical uncertainties affecting the particle physics interpretation of this process. In this report, we review the main aspects of the double beta decay pro...

  10. Experimental beta-alaninuria induced by (aminooxyacetate.

    Directory of Open Access Journals (Sweden)

    Kurozumi Y


    Full Text Available Experimental beta-alaninuria was induced in rats by injection of (aminooxyacetate (AOA, a potent inhibitor of aminotransferases, in order to elucidate the pathogenesis of hyper-beta-alaninemia. A 27-fold increase of beta-alanine (BALA excretion was induced by subcutaneous injection of 1 5 mg of AOA per kg of body weight. A 13-fold and a 9-fold increase of beta-aminoisobutyric acid (BAIBA and gamma-aminobutyric acid (GABA, respectively, were also induced simultaneously by the AOA injection. Identification of BALA and BAIBA isolated from the rat urine was performed by chromatographic and mass spectrometric analyses. The effects of AOA injection on the tissue levels of these amino acids were also studied. Contents of BALA in the liver and kidney and GABA in the brain increased significantly in response to AOA injection. The present study indicates that BALA transaminase is involved in hyper-beta-alaninemia.

  11. Complement activation by the amyloid proteins A beta peptide and beta 2-microglobulin

    DEFF Research Database (Denmark)

    Nybo, Mads; Nielsen, E H; Svehag, S E


    Complement activation (CA) has been reported to play a role in the pathogenesis of Alzheimer's disease (AD). To investigate whether CA may contribute to amyloidogenesis in general, the CA potential of different amyloid fibril proteins was tested. CA induced by A beta preparations containing soluble...... protein, protofilaments and some fibrils or only fibrils in a solid phase system (ELISA) was modest with a slow kinetics compared to the positive delta IgG control. Soluble A beta induced no detectable CA in a liquid phase system (complement consumption assay) while fibrillar A beta caused CA at 200 mg....../ml and higher concentrations. Soluble beta 2-microglobulin (beta 2M) purified from peritoneal dialysates was found to be as potent a complement activator as A beta in both solid and liquid phase systems while beta 2M purified from urine exhibited lower activity, a difference which may be explained...

  12. Clusters of conserved beta cell marker genes for assessment of beta cell phenotype

    DEFF Research Database (Denmark)

    Martens, Geert A; Jiang, Lei; Hellemans, Karine H;


    The aim of this study was to establish a gene expression blueprint of pancreatic beta cells conserved from rodents to humans and to evaluate its applicability to assess shifts in the beta cell differentiated state. Genome-wide mRNA expression profiles of isolated beta cells were compared to those...... of a large panel of other tissue and cell types, and transcripts with beta cell-abundant and -selective expression were identified. Iteration of this analysis in mouse, rat and human tissues generated a panel of conserved beta cell biomarkers. This panel was then used to compare isolated versus laser capture...... microdissected beta cells, monitor adaptations of the beta cell phenotype to fasting, and retrieve possible conserved transcriptional regulators....

  13. Painlev\\'e representation of Tracy-Widom$_\\beta$ distribution for $\\beta = 6$

    CERN Document Server

    Rumanov, Igor


    In \\cite{betaFP1}, we found explicit Lax pairs for the soft edge of beta ensembles with even integer values of $\\beta$. Using this general result, the case $\\beta=6$ is further considered here. This is the smallest even $\\beta$, when the corresponding Lax pair and its relation to Painlev\\'e II (PII) have not been known before, unlike cases $\\beta=2$ and $4$. It turns out that again everything can be expressed in terms of the Hastings-McLeod solution of PII. In particular, a second order nonlinear ODE for the logarithmic derivative of Tracy-Widom distribution for $\\beta=6$ involving the PII function in the coefficients, is found, which allows one to compute asymptotics for the distribution function. The ODE is a consequence of a linear system of three ODEs for which the local Painlev\\'e analysis yields series solutions with exponents in the set $4/3$, $1/3$ and $-2/3$.

  14. Source Water Protection Contaminant Sources (United States)

    Iowa State University GIS Support and Research Facility — Simplified aggregation of potential contaminant sources used for Source Water Assessment and Protection. The data is derived from IDNR, IDALS, and US EPA program...

  15. Expression of TGF-beta1, TGF-beta2, TGF-beta3 and the receptors TGF-betaRI and TGF-betaRII in placentomes of artificially inseminated and nuclear transfer derived bovine pregnancies. (United States)

    Ravelich, S R; Shelling, A N; Wells, D N; Peterson, A J; Lee, R S F; Ramachandran, A; Keelan, J A


    Bovine nuclear transfer pregnancies are characterized by a high incidence of placental abnormalities, notably, increased placentome size and deficiencies in trophoblast cell function and establishment of placental vasculature. Alterations in gene expression during placental growth and development may contribute to the appearance of large placentomes in pregnancies derived from nuclear transfer. The placenta synthesizes a number of cytokines and growth factors, including the transforming growth factor-betas (TGF-betas) that are involved in the establishment, maintenance and/or regulation of pregnancy. All forms of TGF-beta and their receptors are present at the fetal-maternal interface of the bovine placentome, where they are thought to play an important role in regulating growth, differentiation, and function of the placenta. Using real-time RT-PCR, we have examined the expression of TGF-beta1, TGF-beta2, TGF-beta3 and the receptors TGF-betaRI and TGF-betaRII in placentomes of artificially inseminated (AI) and nuclear transfer (NT)-derived bovine pregnancies at days 50, 100 and 150 of gestation. TGF-beta1, TGF-beta2 and TGF-beta3 mRNA expression increased by 2.0-2.8-fold, while TGF-betaRI and TGF-betaRII mRNA expression decreased by 1.7-2.0-fold in NT placentomes compared to AI controls at all gestational ages examined. These findings indicate that NT placentomes may be resistant to the growth suppressive effects of TGF-betas and could contribute to the placental proliferative abnormalities observed in NT-derived placentas. Alternatively, deficiencies in placentation may provide a mechanism whereby TGF-betas are dysregulated in NT pregnancies.

  16. Hanford beta-gamma personnel dosimeter prototypes and evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Fix, J.J.; Holbrook, K.L.; Soldat, K.L.


    Upgraded and modified Hanford dosimeter prototypes were evaluated for possible use at Hanford as a primary beta-gamma dosimeter. All prototypes were compatible with the current dosimeter card and holder design, as well as processing with the automated Hanford readers. Shallow- and deep-dose response was determined for selected prototypes using several beta sources, K-fluorescent x rays and filtered x-ray techniques. All prototypes included a neutron sensitive chip. A progressive evaluation of the performance of each of the upgrades to the current dosimeter is described. In general, the performance of the current dosimeter can be upgraded using individual chip sensitivity factors to improve precision and an improved algorithm to minimize bias. The performance of this dosimeter would be adequate to pass all categories of the ANSI N13.11 performance criteria for dosimeter procesors, provided calibration techniques compatible with irradiations adopted in the standard were conducted. The existing neutron capability of the dosimeter could be retained. Better dosimeter performance to beta-gamma radiation can be achieved by modifying the Hanford dosimeter so that four of the five chip positions are devoted to calculating these doses instead of the currently used two chip positions. A neutron sensitive chip was used in the 5th chip position, but all modified dosimeter prototypes would be incapable of discriminating between thermal and epithermal neutrons. An improved low energy beta response can be achieved for the current dosimeter and all prototypes considered by eliminating the security credential. Further improvement can be obtained by incorporating the 15-mil thick TLD-700 chips.

  17. Collective search by mobile robots using alpha-beta coordination

    Energy Technology Data Exchange (ETDEWEB)

    Goldsmith, S.Y.; Robinett, R. III


    One important application of mobile robots is searching a geographical region to locate the origin of a specific sensible phenomenon. Mapping mine fields, extraterrestrial and undersea exploration, the location of chemical and biological weapons, and the location of explosive devices are just a few potential applications. Teams of robotic bloodhounds have a simple common goal; to converge on the location of the source phenomenon, confirm its intensity, and to remain aggregated around it until directed to take some other action. In cases where human intervention through teleoperation is not possible, the robot team must be deployed in a territory without supervision, requiring an autonomous decentralized coordination strategy. This paper presents the alpha beta coordination strategy, a family of collective search algorithms that are based on dynamic partitioning of the robotic team into two complementary social roles according to a sensor based status measure. Robots in the alpha role are risk takers, motivated to improve their status by exploring new regions of the search space. Robots in the beta role are motivated to improve but are conservative, and tend to remain aggregated and stationary until the alpha robots have identified better regions of the search space. Roles are determined dynamically by each member of the team based on the status of the individual robot relative to the current state of the collective. Partitioning the robot team into alpha and beta roles results in a balance between exploration and exploitation, and can yield collective energy savings and improved resistance to sensor noise and defectors. Alpha robots waste energy exploring new territory, and are more sensitive to the effects of ambient noise and to defectors reporting inflated status. Beta robots conserve energy by moving in a direct path to regions of confirmed high status.

  18. Problems with packaged sources in foreign countries

    Energy Technology Data Exchange (ETDEWEB)

    Abeyta, Cristy L [Los Alamos National Laboratory; Matzke, James L [Los Alamos National Laboratory; Zarling, John [Los Alamos National Laboratory; Tompkin, J. Andrew [Los Alamos National Laboratory


    The Global Threat Reduction Initiative's (GTRI) Off-Site Source Recovery Project (OSRP), which is administered by the Los Alamos National Laboratory (LANL), removes excess, unwanted, abandoned, or orphan radioactive sealed sources that pose a potential threat to national security, public health, and safety. In total, GTRI/OSRP has been able to recover more than 25,000 excess and unwanted sealed sources from over 825 sites. In addition to transuranic sources, the GTRI/OSRP mission now includes recovery of beta/gamma emitting sources, which are of concern to both the U.S. government and the International Atomic Energy Agency (IAEA). This paper provides a synopsis of cooperative efforts in foreign countries to remove excess and unwanted sealed sources by discussing three topical areas: (1) The Regional Partnership with the International Atomic Energy Agency; (2) Challenges in repatriating sealed sources; and (3) Options for repatriating sealed sources.

  19. Metrological characteristics of the new BSS2 beta secondary standard system; Caracteristicas metrologicas do novo sistema padrao secundario beta - BSS2

    Energy Technology Data Exchange (ETDEWEB)

    Reynaldo, Sibele R. [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear; Floresta, Denise L.; Soares, Carlos M. de A.; Silva, Teogenes A. da [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)


    Due to the increased interest and the importance of beta radiation dosimetry for radiation protection purposes, the Centro de Desenvolvimento da Tecnologia Nuclear. MG, Brazil, acquired the newest Beta Secondary Standard system (BSS2) in order to replace the old BSS1 model, with the goal of implement a beta radiation metrology laboratory and provide the corresponding reference radiation. The new system BSS2, unique in Latin America, requires operational testing and metrological characterization for reliability purposes. For this, some comparative investigations of the two systems were made. The influence of opening and closing the shutter in the final dose of radiation was identified as the highest in the BSS2 in relation to the one founded in BSS1, justified by the structural difference of the shutters of the systems and the reproducibility of source-detector geometry was better in BSS2, because of the robustness of the same.

  20. A possible origin of the endpoint anomaly in tritium $\\beta$-spectrum

    CERN Document Server

    Rizek, J; Dragoun, O; Rysavy, M; Spalek, A


    The influence of the residual T atoms appearing after the decay of T_2 molecule on the beta-spectrum shape is considered. Recent experiments performed in Mainz, Troitsk, and Livermore are briefly reviewed from this viewpoint. Aspects connected with the possible time dependent change of the tritium source composition are discussed.

  1. Laser ionization in {beta} decay studies of Zn and Mn nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Oinonen, M.; Jading, Y.; Koester, U.; Lettry, J.; Ravn, H.; Aystoe, J. [CERN, EP Division/ISOLDE (Switzerland); Dendooven, P.; Huikari, J.; Jokinen, A.; Lipas, P.O.; Nieminen, A.; Peraejaervi, K.; Siiskonen, T. [University of Jyvaeskylae, Department of Physics (Finland); Baumann, P.; Huck, A.; Knipper, A.; Ramdhane, M.; Walter, G. [Institut de Recherches Subatomiques (France); Didierjean, F. [Eurisys Measures (France); Fedoseyev, V.N. [Russian Academy of Sciences, Institute of Spectroscopy (Russian Federation)] (and others)


    Resonance ionization laser ion source (RILIS) technique has been used in the {beta}-decay studies of {sup 59}Mn and {sup 58}Zn. The importance of the RILIS for production of these elements is discussed. The properties of the low-lying levels of the studied nuclei are discussed.

  2. Synthesis of zeolite beta with pretreated rice husk silica and its transformation to ZSM-12

    Energy Technology Data Exchange (ETDEWEB)

    Loiha, Sirinuch [Material Chemistry Research Unit, School of Chemistry, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima 30000 (Thailand); Synchrotron Light Research Institute (Public Organization), Nakhon Ratchasima 30000 (Thailand); Prayoonpokarach, Sanchai [Material Chemistry Research Unit, School of Chemistry, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima 30000 (Thailand); Songsiriritthigun, Prayoon [Synchrotron Light Research Institute (Public Organization), Nakhon Ratchasima 30000 (Thailand); Wittayakun, Jatuporn, E-mail: [Material Chemistry Research Unit, School of Chemistry, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima 30000 (Thailand); Center of Environmental and Hazardous Waste Management (EHWM), Thammasat University, Pathumtani 12120 (Thailand)


    Silica with 98% purity was prepared from rice husk by acid leaching and used as a silica source for the syntheses of zeolite beta (Beta) under hydrothermal conditions with gel Si/Al ratios of 8, 13, 15, 20, 50, 100, 150, and 200. Based on powder X-ray diffraction patterns, samples with gel Si/Al ratios of 8-20 contained only the pure phase of Beta and the highest relative crystallinity was observed in the Beta with gel Si/Al ratio of 13. This sample was further characterized by scanning electron microscopy, particle size analyzer and N{sub 2} adsorption analysis. The Beta particles were sphere shaped with the average particle size of 1.5 {mu}m and a surface area of 670 m{sup 2} g{sup -1}. The samples with gel Si/Al ratios ranging from 50 to 200 showed mixed phases of Beta and ZSM-12, and the latter phase was more dominant as the Si/Al ratio increased.

  3. Field tests of a portable tissue equivalent survey meter for monitoring mixed beta/gamma radiation fields

    Energy Technology Data Exchange (ETDEWEB)

    Martz, D.E.; Rich, B.L.; Johnson, L.O.; Daniel, S.H. III


    A portable radiation survey meter that provides a tissue equivalent response to photons and beta particles has been designed and field tested. The detector is a very thin plastic scintillator that closely simulates the actual geometry and scattering properties of the relevant skin tissues. The meter reads out the D(0.07) dose rate directly, and indicates the tissue dose rates at other depths with the use of tissue equivalent filters of appropriate thicknesses. Data are presented which compare the D(0.07) and D(10) dose rates recorded by the Tissue Equivalent (TE) survey meter with dose rates recorded by two commercial ion chamber meters for a number of laboratory and field sources. Most commercial ion chamber meters fail to respond adequately to the extreme off-axis beta particles from extended beta sources, and hence require the application of large beta correction factors to change the instrument reading to the true D(0.07) dose rate. The tissue equivalent survey meter exhibits an angular response to beta particles that is very similar to the angular response of an extrapolation chamber. Consequently, there is close agreement between the TE meter and extrapolation chamber readings for a wide variety of beta and mixed beta-gamma rdiation fields. D(0.07), D(3), and D(10) dose rates, measured with the INEL TE meter at a number of typical work stations, are presented.

  4. Synthesis and characterization of {beta}-Ni(OH){sub 2} up grown nanoflakes by SILAR method

    Energy Technology Data Exchange (ETDEWEB)

    Kulkarni, S.B.; Jamadade, V.S.; Dhawale, D.S. [Thin Film Physics Laboratory, Department of Physics, Shivaji University, Kolhapur 416 004, M.S. (India); Lokhande, C.D., E-mail: [Thin Film Physics Laboratory, Department of Physics, Shivaji University, Kolhapur 416 004, M.S. (India)


    In this paper we report a 'bottom up' approach to synthesize {beta}-Ni(OH){sub 2} nanoflakes using novel successive ionic layer adsorption and reaction (SILAR) method. Ni(OH){sub 2} thin films have been deposited on glass substrate using aqueous alkaline nickel chloride as nickel ion source and double distilled water maintained at 353 K temperature as hydroxyl ion source. The structural, surface morphological, optical and electrical properties of films are examined. The nanocrystallinity and {beta}-phase of Ni(OH){sub 2} are confirmed by X-ray diffraction and FT-IR studies. Scanning electron microscope study revealed microporous and random distribution of well up grown interlocked nanoflakes. Optical absorption studies show wide optical band gap of 3.26 eV for {beta}-Ni(OH){sub 2}. The electrical properties revealed that {beta}-Ni(OH){sub 2} has negative temperature coefficient of resistance with p-type semiconducting behaviour. The electrochemical property studied by cyclic voltametry in 2 M KOH electrolyte solution revealed pseudo capacitive behaviour, when {beta}-Ni(OH){sub 2} thin film employed as working electrode in three electrode electrochemical cell with platinum as counter electrode and saturated calomel as reference electrode. The specific capacitance of 350 F g{sup -1} is obtained with nanoflake like morphology.

  5. Clusters of conserved beta cell marker genes for assessment of beta cell phenotype

    DEFF Research Database (Denmark)

    Martens, Geert A; Jiang, Lei; Hellemans, Karine H;


    The aim of this study was to establish a gene expression blueprint of pancreatic beta cells conserved from rodents to humans and to evaluate its applicability to assess shifts in the beta cell differentiated state. Genome-wide mRNA expression profiles of isolated beta cells were compared to those...... microdissected beta cells, monitor adaptations of the beta cell phenotype to fasting, and retrieve possible conserved transcriptional regulators.......The aim of this study was to establish a gene expression blueprint of pancreatic beta cells conserved from rodents to humans and to evaluate its applicability to assess shifts in the beta cell differentiated state. Genome-wide mRNA expression profiles of isolated beta cells were compared to those...... of a large panel of other tissue and cell types, and transcripts with beta cell-abundant and -selective expression were identified. Iteration of this analysis in mouse, rat and human tissues generated a panel of conserved beta cell biomarkers. This panel was then used to compare isolated versus laser capture...

  6. Ellagic acid promotes A{beta}42 fibrillization and inhibits A{beta}42-induced neurotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Ying [Department of Histology and Embryology, College of Basic Medical Science, China Medical University, Shenyang 110001 (China); Tsinghua University School of Medicine, Haidian District, Beijing 100084 (China); Yang, Shi-gao; Du, Xue-ting; Zhang, Xi; Sun, Xiao-xia; Zhao, Min [Tsinghua University School of Medicine, Haidian District, Beijing 100084 (China); Sun, Gui-yuan, E-mail: [Department of Histology and Embryology, College of Basic Medical Science, China Medical University, Shenyang 110001 (China); Liu, Rui-tian, E-mail: [Tsinghua University School of Medicine, Haidian District, Beijing 100084 (China)


    Smaller, soluble oligomers of {beta}-amyloid (A{beta}) play a critical role in the pathogenesis of Alzheimer's disease (AD). Selective inhibition of A{beta} oligomer formation provides an optimum target for AD therapy. Some polyphenols have potent anti-amyloidogenic activities and protect against A{beta} neurotoxicity. Here, we tested the effects of ellagic acid (EA), a polyphenolic compound, on A{beta}42 aggregation and neurotoxicity in vitro. EA promoted A{beta} fibril formation and significant oligomer loss, contrary to previous results that polyphenols inhibited A{beta} aggregation. The results of transmission electron microscopy (TEM) and Western blot displayed more fibrils in A{beta}42 samples co-incubated with EA in earlier phases of aggregation. Consistent with the hypothesis that plaque formation may represent a protective mechanism in which the body sequesters toxic A{beta} aggregates to render them harmless, our MTT results showed that EA could significantly reduce A{beta}42-induced neurotoxicity toward SH-SY5Y cells. Taken together, our results suggest that EA, an active ingredient in many fruits and nuts, may have therapeutic potential in AD.

  7. Evidence for Novel [beta]-Sheet Structures in Iowa Mutant [beta]-Amyloid Fibrils

    Energy Technology Data Exchange (ETDEWEB)

    Tycko, Robert; Sciarretta, Kimberly L.; Orgel, Joseph P.R.O.; Meredith, Stephen C.; (IIT); (NIH); (UC)


    Asp23-to-Asn mutation within the coding sequence of {beta}-amyloid, called the Iowa mutation, is associated with early onset, familial Alzheimer's disease and cerebral amyloid angiopathy, in which patients develop neuritic plaques and massive vascular deposition predominantly of the mutant peptide. We examined the mutant peptide, D23N-A{beta}40, by electron microscopy, X-ray diffraction, and solid-state NMR spectroscopy. D23N-A{beta}40 forms fibrils considerably faster than the wild-type peptide (k = 3.77 x 10{sup -3} min{sup -1} and 1.07 x 10{sup -4} min{sup -1} for D23N-A{beta}40 and the wild-type peptide WT-A{beta}40, respectively) and without a lag phase. Electron microscopy shows that D23N-A{beta}40 forms fibrils with multiple morphologies. X-ray fiber diffraction shows a cross-{beta} pattern, with a sharp reflection at 4.7 {angstrom} and a broad reflection at 9.4 {angstrom}, which is notably smaller than the value for WT-A{beta}40 fibrils (10.4 {angstrom}). Solid-state NMR measurements indicate molecular level polymorphism of the fibrils, with only a minority of D23N-A{beta}40 fibrils containing the in-register, parallel {beta}-sheet structure commonly found in WT-A{beta}40 fibrils and most other amyloid fibrils. Antiparallel {beta}-sheet structures in the majority of fibrils are indicated by measurements of intermolecular distances through 13C-13C and 15N-13C dipole-dipole couplings. An intriguing possibility exists that there is a relationship between the aberrant structure of D23N-A{beta}40 fibrils and the unusual vasculotropic clinical picture in these patients.

  8. Scintillating bolometers for Double Beta Decay search

    CERN Document Server

    Gironi, Luca


    In the field of Double Beta Decay (DBD) searches, the use of high resolution detectors in which background can be actively discriminated is very appealing. Scintillating bolometers containing a Double Beta Decay emitter can largely fulfill this very interesting possibility. In this paper we present the latest results obtained with CdWO4 and CaMoO4 crystals. Moreover we report, for the first time, a very interesting feature of CaMoO4 bolometers: the possibility to discriminate beta-gamma events from those induced by alpha particles thanks to different thermal pulse shape.

  9. Beta-2-mikroglobulin ved medicinske sygdomme

    DEFF Research Database (Denmark)

    Hansen, P B; Olsen, Niels Vidiendal


    -interstitial nephropathy, increased quantities of beta 2M are excreted in the urine. If the rate of glomerular filtration is reduced, serum-beta 2M is increased and this is also the case in persons with increased cell division despite normal renal function. Serum-beta 2M is, therefore, raised in numerous malignant...... must be presumed to be of value not only in the diagnosis of cerebral AIDS and other (latent) CNS infections but also to demonstrate complicating cerebral malignant lymphomata at an early stage....

  10. Silent ischemia and beta-blockade

    DEFF Research Database (Denmark)

    Egstrup, K


    and should also be directed at the other coronary artery risk factors of the patients. The effects of beta-blockers, which reduce the duration and frequency of silent ischemic episodes, is well described. The effect is most pronounced in the morning, when the frequency of ischemia is highest......, and the mechanism of action seems mainly mediated through a reduction in myocardial oxygen demand. beta-Blockers have shown effectiveness in both effort-induced angina and mixed angina, and increased anti-ischemic potency may be achieved by combination therapy with a calcium antagonist. Abrupt withdrawal of beta-blockers...

  11. Dopamine beta-hydroxylase deficiency

    Directory of Open Access Journals (Sweden)

    Senard Jean-Michel


    Full Text Available Abstract Dopamine beta-hydroxylase (DβH deficiency is a very rare form of primary autonomic failure characterized by a complete absence of noradrenaline and adrenaline in plasma together with increased dopamine plasma levels. The prevalence of DβH deficiency is unknown. Only a limited number of cases with this disease have been reported. DβH deficiency is mainly characterized by cardiovascular disorders and severe orthostatic hypotension. First symptoms often start during a complicated perinatal period with hypotension, muscle hypotonia, hypothermia and hypoglycemia. Children with DβH deficiency exhibit reduced ability to exercise because of blood pressure inadaptation with exertion and syncope. Symptoms usually worsen progressively during late adolescence and early adulthood with severe orthostatic hypotension, eyelid ptosis, nasal stuffiness and sexual disorders. Limitation in standing tolerance, limited ability to exercise and traumatic morbidity related to falls and syncope may represent later evolution. The syndrome is caused by heterogeneous molecular alterations of the DBH gene and is inherited in an autosomal recessive manner. Restoration of plasma noradrenaline to the normal range can be achieved by therapy with the synthetic precursor of noradrenaline, L-threo-dihydroxyphenylserine (DOPS. Oral administration of 100 to 500 mg DOPS, twice or three times daily, increases blood pressure and reverses the orthostatic intolerance.

  12. Systematic risk variations (beta convertible debenture brazilian companies

    Directory of Open Access Journals (Sweden)

    Renata Drumond Pinto Coelho Antonino


    Full Text Available purpose of this article is to analyze the impact of issuing convertible debentures on the systematic risk of Brazilian companies. Some applied researches in the U.S. capital market (STEIN, 1992; LEWIS et al, 2002; RAI, 2005 indicate that convertible debentures may be used as an alternative financing source when adverse selection problem makes stock issuing unattractive financing source. The analysis of Brazilian companies that issued convertible debentures recorded in the period from 1998 to 2006 and that presented liquidity on the market indicated that variation in beta, on average, is positive. These results are coherent with the signaling hypothesis and with the absence of convertible debenture issuing in 2005 and 2006 on the Brazilian market. They also may be related to the precarious financial situation of issuing companies, observed by the analysis of some financial indicators in year of issue and in two pre- e post-issuing years.

  13. Energetic, Structural, and Antimicrobial Analyses of [beta]-Lactam Side Chain Recognition by [beta]-Lactamases

    Energy Technology Data Exchange (ETDEWEB)

    Caselli, E.; Powers, R.A.; Blaszczak, L.C.; Wu, C.Y.E.; Prati, F.; Shoichet, B.K. (NWU)


    Penicillins and cephalosporins are among the most widely used and successful antibiotics. The emergence of resistance to these {beta}-lactams, most often through bacterial expression of {beta}-lactamases, threatens public health. To understand how {beta}-lactamases recognize their substrates, it would be helpful to know their binding energies. Unfortunately, these have been difficult to measure because {beta}-lactams form covalent adducts with {beta}-lactamases. This has complicated functional analyses and inhibitor design. To investigate the contribution to interaction energy of the key amide (R1) side chain of {beta}-lactam antibiotics, eight acylglycineboronic acids that bear the side chains of characteristic penicillins and cephalosporins, as well as four other analogs, were synthesized. These transition-state analogs form reversible adducts with serine {beta}-lactamases. Therefore, binding energies can be calculated directly from K{sub i} values. The K{sub i} values measured span four orders of magnitude against the Group I {beta}-lactamase AmpC and three orders of magnitude against the Group II {beta}-lactamase TEM-1. The acylglycineboronic acids have K{sub i} values as low as 20 nM against AmpC and as low as 390 nM against TEM-1. The inhibitors showed little activity against serine proteases, such as chymotrypsin. R1 side chains characteristic of {beta}-lactam inhibitors did not have better affinity for AmpC than did side chains characteristic of {beta}-lactam substrates. Two of the inhibitors reversed the resistance of pathogenic bacteria to {beta}-lactams in cell culture. Structures of two inhibitors in their complexes with AmpC were determined by X-ray crystallography to 1.90 {angstrom} and 1.75 {angstrom} resolution; these structures suggest interactions that are important to the affinity of the inhibitors. Acylglycineboronic acids allow us to begin to dissect interaction energies between {beta}-lactam side chains and {beta}-lactamases. Surprisingly

  14. Optimizing the greenfield Beta-beam

    Energy Technology Data Exchange (ETDEWEB)

    Agarwalla, Sanjib Kumar; Choubey, Sandhya; Raychaudhuri, Amitava [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211019 (India); Winter, Walter [Institut fuer Theoretische Physik und Astrophysik, Universitaet Wuerzburg, Am Hubland, D-97074 Wuerzburg (Germany)], E-mail:


    A comprehensive and detailed comparison of the physics reach of Beta-beam experiments between two pairs of plausible source ions, ({sup 8}B, {sup 8}Li) and ({sup 18}Ne, {sup 6}He) is performed. We study the optimal choices for the baseline, boost factor, and luminosity. We take a 50 kton iron calorimeter, a la ICAL-INO, as the far detector. We follow two complementary approaches for our study: (i) Fixing the number of useful ion decays and boost factor of the beam, and optimizing for the sensitivity reach between the two pairs of ions as a function of the baseline, (ii) Matching the shape of the spectrum between the two pairs of ions, and studying the requirements for baseline, boost factor, and luminosity. We find that for each pair of ions there are two baselines with very good sensitivity reaches: a short baseline with L [km]/{gamma} {approx_equal} 2.6 ({sup 8}B+{sup 8}Li) and L [km]/{gamma} {approx_equal} 0.8 ({sup 18}Ne+{sup 6}He), respectively, and a long 'magic' baseline. For {gamma} {approx} 500, one would optimally use {sup 6}He and {sup 18}Ne at the short baseline for CP violation, {sup 8}B and {sup 8}Li at the magic baseline for the mass hierarchy, and either {sup 6}He and {sup 18}Ne at the short baseline or {sup 8}B and {sup 8}Li at the magic baseline for the sin{sup 2} 2{theta}{sub 13} discovery.

  15. Adenoviruses Expressing PDX-1, BETA2/NeuroD and MafA Induces the Transdifferentiation of Porcine Neonatal Pancreas Cell Clusters and Adult Pig Pancreatic Cells into Beta-Cells

    Directory of Open Access Journals (Sweden)

    Young-Hye You


    Full Text Available BackgroundA limitation in the number of insulin-producing pancreatic beta-cells is a special feature of diabetes. The identification of alternative sources for the induction of insulin-producing surrogate beta-cells is a matter of profound importance. PDX-1/VP16, BETA2/NeuroD, and MafA overexpression have been shown to influence the differentiation and proliferation of pancreatic stem cells. However, few studies have been conducted using adult animal pancreatic stem cells.MethodsAdult pig pancreatic cells were prepared from the non-endocrine fraction of adult pig pancreata. Porcine neonatal pancreas cell clusters (NPCCs were prepared from neonatal pigs aged 1-2 days. The dispersed pancreatic cells were infected with PDX-1/VP16, BETA2/NeuroD, and MafA adenoviruses. After infection, these cells were transplanted under the kidney capsules of normoglycemic nude mice.ResultsThe adenovirus-mediated overexpression of PDX-1, BETA2/NeuroD and MafA induced insulin gene expression in NPCCs, but not in adult pig pancreatic cells. Immunocytochemistry revealed that the number of insulin-positive cells in NPCCs and adult pig pancreatic cells was approximately 2.6- and 1.1-fold greater than those in the green fluorescent protein control group, respectively. At four weeks after transplantation, the relative volume of insulin-positive cells in the grafts increased in the NPCCs, but not in the adult porcine pancreatic cells.ConclusionThese data indicate that PDX-1, BETA2/NeuroD, and MafA facilitate the beta-cell differentiation of NPCCs, but not adult pig pancreatic cells. Therefore PDX-1, BETA2/NeuroD, and MafA-induced NPCCs can be considered good sources for the induction of pancreatic beta-cells, and may also have some utility in the treatment of diabetes.

  16. Systematic Risk on Istanbul Stock Exchange: Traditional Beta Coefficient Versus Downside Beta Coefficient

    Directory of Open Access Journals (Sweden)

    Gülfen TUNA


    Full Text Available The aim of this study is to test the validity of Downside Capital Asset Pricing Model (D-CAPM on the ISE. At the same time, the explanatory power of CAPM's traditional beta and D-CAPM's downside beta on the changes in the average return values are examined comparatively. In this context, the monthly data for seventy three stocks that are continuously traded on the ISE for the period 1991-2009 is used. Regression analysis is applied in this study. The research results have shown that D-CAPM is valid on the ISE. In addition, it is obtained that the power of downside beta coefficient is higher than traditional beta coefficient on explaining the return changes. Therefore, it can be said that the downside beta is superior to traditional beta in the ISE for chosen period.

  17. Synthesis of mesoporous Beta and Sn-Beta zeolites and their catalytic performances. (United States)

    Jin, Junjiang; Ye, Xinxin; Li, Yongsheng; Wang, Yanqin; Li, Liang; Gu, Jinlou; Zhao, Wenru; Shi, Jianlin


    Mesoporous Beta zeolite has been successfully prepared through hydrothermal synthesis in the presence of cationic ammonium-modified chitosan as the meso-template. Through a subsequent solid-gas reaction between highly dealuminated mesoporous Beta zeolite and SnCl4 steam at an elevated temperature, mesoporous Sn-Beta has been facilely obtained. It was revealed that the addition of cationic chitosan induced the nanocrystal aggregation to particle sizes of ∼300 nm, giving rise to the intercrystalline/interparticle mesoporosity. In the Sn-implanting procedure, Sn species were demonstrated to be doped into the framework of the resulting mesoporous Beta zeolite in a tetrahedral environment without structural collapse. Due to the micro/mesoporous structures, both mesoporous Beta and Sn-Beta exhibited superior performances in α-pinene isomerization, Baeyer-Villiger oxidation of 2-adamantanone by hydrogen peroxide and the isomerization of glucose in water, respectively.

  18. Expression of transforming growth factor beta (TGF beta) receptors and expression of TGF beta 1, TGF beta 2 and TGF beta 3 in human small cell lung cancer cell lines

    DEFF Research Database (Denmark)

    Damstrup, L; Rygaard, K; Spang-Thomsen, M;


    A panel of 21 small cell lung cancer cell (SCLC) lines were examined for the presence of Transforming growth factor beta receptors (TGF beta-r) and the expression of TGF beta mRNAs. By the radioreceptor assay we found high affinity receptors to be expressed in six cell lines. scatchard analysis...... of the binding data demonstrated that the cells bound between 4.5 and 27.5 fmol mg-1 protein with a KD ranging from 16 to 40 pM. TGF beta 1 binding to the receptors was confirmed by cross-linking TGF beta 1 to the TGF beta-r. Three classes of TGF beta-r were demonstrated, type I and type II receptors with M......(r) = 65,000 and 90,000 and the betaglycan (type III) with M(r) = 280,000. Northern blotting showed expression of TGF beta 1 mRNA in ten, TGF beta 2 mRNA in two and TGF beta 3 mRNA in seven cell lines. Our results provide, for the first time, evidence that a large proportion of a broad panel of SCLC cell...

  19. Beta-2 Microglobulin Kidney Disease Test (United States)

    ... Beta 2 Microglobulin, Serum or Urine Related tests: Albumin , Creatinine , BUN , Heavy Metals Were you looking for ... monitor persons with end-stage renal disease (ESRD) Excess B2M can accumulate in joint spaces ( synovitis ) in ...

  20. Probing neutrinoless double beta decay with SNO+

    CERN Document Server

    Arushanova, Evelina


    Probing neutrinoless double beta decay is one of the primary goals for SNO+, SNOLAB's multi-purpose neutrino detector. In order to achieve this goal the SNO detector has been adapted so that it can be filled with Te-loaded liquid scintillator. During the initial double beta phase the target loading is 0.3% natural Te, which equates to $\\sim790$ kg of double beta isotope. Estimating the sensitivity to neutrinoless double beta decay requires a well understood background model. For SNO+ this is provided by a comprehensive study considering all possible background contributions, whether they originate from within the liquid scintillator cocktail, the surrounding parts of the detector or other irreducible backgrounds. Given these considerations, for five years running in the initial phase, the expected sensitivity is $T_{1/2}^{0\

  1. Neutrino potential for neutrinoless double beta decay

    CERN Document Server

    Iwata, Yoritaka


    Neutrino potential for neutrinoless double beta decay is studied with focusing on its statistical property. The statistics provide a gross view of understanding amplitude of constitutional components of the nuclear matrix element.

  2. Beta cell proliferation and growth factors

    DEFF Research Database (Denmark)

    Nielsen, Jens Høiriis; Svensson, C; Møldrup, Annette


    Formation of new beta cells can take place by two pathways: replication of already differentiated beta cells or neogenesis from putative islet stem cells. Under physiological conditions both processes are most pronounced during the fetal and neonatal development of the pancreas. In adulthood little...... increase in the beta cell number seems to occur. In pregnancy, however, a marked hyperplasia of the beta cells is observed both in rodents and man. Increased mitotic activity has been seen both in vivo and in vitro in islets exposed to placental lactogen (PL), prolactin (PRL) and growth hormone (GH......). Receptors for both GH and PRL are expressed in islet cells and are upregulated during pregnancy. By mutational analysis we have identified different functional domains of the cytoplasmic part of the GH receptor. Thus the mitotic signaling only requires the membrane proximal part of the receptor...

  3. Phenomenology of neutrinoless double beta decay

    CERN Document Server

    Gómez-Cadenas, J J


    This paper reviews the current status and future outlook of neutrinoless double beta decay searches, which try to provide an answer to the fundamental question of whether neutrinos are Dirac or Majorana particles.

  4. Literature in Focus Beta Beams: Neutrino Beams

    CERN Multimedia


    By Mats Lindroos (CERN) and Mauro Mezzetto (INFN Padova, Italy) Imperial Press, 2009 The beta-beam concept for the generation of electron neutrino beams was first proposed by Piero Zucchelli in 2002. The idea created quite a stir, challenging the idea that intense neutrino beams only could be produced from the decay of pions or muons in classical neutrino beams facilities or in future neutrino factories. The concept initially struggled to make an impact but the hard work by many machine physicists, phenomenologists and theoreticians over the last five years has won the beta-beam a well-earned position as one of the frontrunners for a possible future world laboratory for high intensity neutrino oscillation physics. This is the first complete monograph on the beta-beam concept. The book describes both technical aspects and experimental aspects of the beta-beam, providing students and scientists with an insight into the possibilities o...

  5. [Beta 3 adrenergic receptor polymorphism and obesity]. (United States)

    Yoshida, T; Umekawa, T


    The beta 3-adrenoceptor plays a significant role in the control of lipolysis and thermogenesis in the brown adipose tissue of rodents and humans. In human beta 3-adrenoceptor, a Trp to Arg replacement has recently been discovered. This change which occurs at position 64, in the first coding exon, has been correlated with increased weight gain, difficulty in losing weight, insulin resistance syndrome, and worsened diabetic situation. Higher percentages of this mutation are observed in Pima Indians (over 30%) and Japanese (20%). The possible functional mechanism of Trp54Arg is reported using human HEK293 cell line stably expressing the wild type and the [Arg64] beta 3-adrenoceptor type. Beta 3-adrenoceptor agonists available for humans are been also developing. In this paper we describe these points up-to-date.

  6. [Allergy to beta-lactam antibiotics]. (United States)

    Comte, D; Petitpierre, S; Spertini, F; Bart, P-A


    Beta-lactam antibiotics allergies are common. Up to 10% of the population describe a former allergy to penicillins. However only 10 to 15% of these individuals are actually allergic. In most cases, beta-lactam antibiotics will be avoided and replaced by other antibiotics such as quinolones. This fear of a serious allergic reaction has an economic impact and may lead to the emergence of antibiotic resistance. A thorough allergic work-up can accurately determine true allergic patients. Most of the patients with a proven allergy will be able to tolerate other antibiotics belonging to the beta-lactam family. This article focuses on the management of beta-lactam allergic patients.

  7. Metabolic response to various beta-adrenoceptor agonists in beta3-adrenoceptor knockout mice: evidence for a new beta-adrenergic receptor in brown adipose tissue. (United States)

    Preitner, F; Muzzin, P; Revelli, J P; Seydoux, J; Galitzky, J; Berlan, M; Lafontan, M; Giacobino, J P


    The beta3-adrenoceptor plays an important role in the adrenergic response of brown and white adipose tissues (BAT and WAT). In this study, in vitro metabolic responses to beta-adrenoceptor stimulation were compared in adipose tissues of beta3-adrenoceptor knockout and wild type mice. The measured parameters were BAT fragment oxygen uptake (MO2) and isolated white adipocyte lipolysis. In BAT of wild type mice (-)-norepinephrine maximally stimulated MO2 4.1+/-0.8 fold. Similar maximal stimulations were obtained with beta1-, beta2- or beta3-adrenoceptor selective agonists (dobutamine 5.1+/-0.3, terbutaline 5.3+/-0.3 and CL 316,243 4.8+/-0.9 fold, respectively); in BAT of beta3-adrenoceptor knockout mice, the beta1- and beta2-responses were fully conserved. In BAT of wild type mice, the beta1/beta2-antagonist and beta3-partial agonist CGP 12177 elicited a maximal MO2 response (4.7+/-0.4 fold). In beta3-adrenoceptor knockout BAT, this response was fully conserved despite an absence of response to CL 316,243. This unexpected result suggests that an atypical beta-adrenoceptor, distinct from the beta1-, beta2- and beta3-subtypes and referred to as a putative beta4-adrenoceptor is present in BAT and that it can mediate in vitro a maximal MO2 stimulation. In isolated white adipocytes of wild type mice, (-)-epinephrine maximally stimulated lipolysis 12.1+/-2.6 fold. Similar maximal stimulations were obtained with beta1-, beta2- or beta3-adrenoceptor selective agonists (TO509 12+/-2, procaterol 11+/-3, CL 316,243 11+/-3 fold, respectively) or with CGP 12177 (7.1+/-1.5 fold). In isolated white adipocytes of beta3-adrenoceptor knockout mice, the lipolytic responses to (-)epinephrine, to the beta1-, beta2-, beta3-adrenoceptor selective agonists and to CGP 12177 were almost or totally depressed, whereas those to ACTH, forskolin and dibutyryl cyclic AMP were conserved.

  8. Status of the Argonne heavy-ion-fusion low-beta linac

    Energy Technology Data Exchange (ETDEWEB)

    Watson, J.M.; Bogaty, J.M.; Moretti, A.; Sacks, R.A.; Sesol, N.Q.; Wright, A.J.


    The primary goal of the experimental program in heavy-ion fusion (HIF) at Argonne National Laboratory (ANL) during the next few years is to demonstrate many of the requirements of a RF linac driver for inertial-fusion power plants. So far, most of the construction effort has been applied to the front end. The ANL program has developed a high-intensity xenon source, a 1.5-MV preaccelerator, and the initial cavities of the low-beta linac. The design, initial tests, and status of the low-beta linac are described.

  9. Status of the Argonne heavy ion fusion low-beta linac

    Energy Technology Data Exchange (ETDEWEB)

    Watson, J.M.; Bogaty, J.M.; Moretti, A.; Sacks, R.A.; Sesol, N.Q.; Wright, A.J.


    The primary goal of the experimental program in heavy ion fusion (HIF) at Argonne National Laboratory (ANL) during the next few years is to demonstrate many of the requirements of a RF linac driver for inertial fusion power plants. So far, most of the construction effort has been applied to the front end. The ANL program has developed a high intensity xenon source, a 1.5 MV preaccelerator, and the initial cavities of the low-beta linac. The design, initial tests and status of the low-beta linac are described. 8 refs.

  10. Measurement of the electron antineutrino mass from the beta spectrum of gaseous tritium

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, D.A.


    A measurement has been made of the mass of the electron antineutrino using the beta spectrum from a source of gaseous molecular tritium, and an upper limit of 36 eV/c/sup 2/ has been set on this mass. This measurement is the first upper limit on neutrino mass that does not rely on assumptions about the atomic configuration after the beta decay, and it has significantly smaller systematic errors associated with it than do previous measurements. 130 refs., 83 figs., 8 tabs.

  11. Isotope Effects in the Bonds of beta-CrOOH and beta-CrOOD

    DEFF Research Database (Denmark)

    Nørlund Christensen, A.; Hansen, P.; Lehmann, M. S.


    Samples of orthorhombic chromium oxide hydroxide, beta -CrOOH, and the deuterated compound, beta -CrOOD, were prepared hydrothermally. The crystal structures were determined by powder profile refinement technique using neutron diffraction data. Unit cells are: beta -CrOOH: a equals 4. 862(2) A, b...... equals 4. 298(a) A, c equals 2. 995(1) A; beta -CrOOD: a equals 4. 873(5) A, b equals 4. 332(7) A, c equals 2. 963(2) A, with Z equals 2. The space group is P2//1nm or Pnnm....

  12. AE activity during transient beta drops in high poloidal beta discharges (United States)

    Huang, J.; Gong, X. Z.; Ren, Q. L.; Ding, S. Y.; Qian, J. P.; Pan, C. K.; Li, G. Q.; Heidbrink, W. W.; Garofalo, A. M.; McClenaghan, J.


    Enhanced AE activity has been observed during transient beta drops in high poloidal beta DIII-D discharges with internal transport barriers (ITBs). These drops in beta are believed to be caused by n=1 external kink modes. In some discharges, beta recovers within 200 ms but, in others, beta stays suppressed. A typical discharge has βP 3, qmin 3, and q95 12. The drop in beta affects both fast ions and thermal particles, and a drop is also observed in the density and rotation. The enhanced AE activity follows the instability that causes the beta drop, is largest at the lowest beta, and subsides as beta recovers. MHD stability analysis is planned. A database study of the plasma conditions associated with the collapse will be also presented. Supported in part by the US Department of Energy under DE-FC02-04ER54698, DE-AC05-06OR23100, and by the National Natural Science Foundation of China 11575249, and the National Magnetic Confinement Fusion Program of China No. 2015GB110005.

  13. Estimating Security Betas Using Prior Information Based on Firm Fundamentals

    NARCIS (Netherlands)

    Cosemans, Mathijs; Frehen, Rik; Schotman, Peter; Bauer, Rob


    We propose a hybrid approach for estimating beta that shrinks rolling window estimates toward firm-specific priors motivated by economic theory. Our method yields superior forecasts of beta that have important practical implications. First, unlike standard rolling window betas, hybrid betas carry a

  14. beta(2)-Glycoprotein I : evolution, structure and function

    NARCIS (Netherlands)

    de Groot, P. G.; Meijers, J. C. M.


    beta(2)-Glycoprotein I (beta(2)-GPI) is a protein that circulates in blood at high concentrations. The function of beta(2)-GPI has long been an enigma. More than 20 years ago, it was discovered that beta(2)-GPI is the major antigen for the circulating antibodies in the antiphospholipid syndrome. How

  15. 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


    $\\beta$-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.

  16. Continuous and Jump Betas: Implications for Portfolio Diversification

    Directory of Open Access Journals (Sweden)

    Vitali Alexeev


    Full Text Available Using high-frequency data, we decompose the time-varying beta for stocks into beta for continuous systematic risk and beta for discontinuous systematic risk. Estimated discontinuous betas for S&P500 constituents between 2003 and 2011 generally exceed the corresponding continuous betas. We demonstrate how continuous and discontinuous betas decrease with portfolio diversification. Using an equiweighted broad market index, we assess the speed of convergence of continuous and discontinuous betas in portfolios of stocks as the number of holdings increase. We show that discontinuous risk dissipates faster with fewer stocks in a portfolio compared to its continuous counterpart.

  17. DMPD: Immunoreceptor-like signaling by beta 2 and beta 3 integrins. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17913496 Immunoreceptor-like signaling by beta 2 and beta 3 integrins. Jakus Z, Fod...or S, Abram CL, Lowell CA, Mocsai A. Trends Cell Biol. 2007 Oct;17(10):493-501. (.png) (.svg) (.html) (.csml) Show Immunore...ceptor-like signaling by beta 2 and beta 3 integrins. PubmedID 17913496 Title Immunoreceptor-

  18. Des-Lys58-beta 2m and native beta 2m in rheumatoid arthritis serum and synovial fluid

    DEFF Research Database (Denmark)

    Williams, R C; Malone, C C; Nissen, Mogens Holst;


    OBJECTIVE. Levels of beta 2-microglobulin and modified beta 2-microglobulin (Des-Lys58-beta 2m) were measured in serum and synovial fluids from patients with rheumatoid arthritis (RA) and other inflammatory joint disorders using rabbit antisera prepared against the beta 2m peptide VEHSDLSFS...

  19. Characterization of beta-R1, a gene that is selectively induced by interferon beta (IFN-beta) compared with IFN-alpha. (United States)

    Rani, M R; Foster, G R; Leung, S; Leaman, D; Stark, G R; Ransohoff, R M


    We report preliminary characterization of a gene designated beta-R1, which is selectively expressed in response to interferon beta (IFN-beta) compared with IFN-alpha. In human astrocytoma cells, beta-R1 was induced to an equivalent extent by 10 IU/mL IFN-beta or 2500 IU/mL IFN-alpha2. To address the mechanism of this differential response, we analyzed induction of the beta-R1 gene in fibrosarcoma cells and derivative mutant cells lacking components required for signaling by type I IFNs. beta-R1 was readily induced by IFN-beta in the parental 2fTGH cell line, but not by recombinant IFN-alpha2, IFN-alpha Con1, or a mixture of IFN-alpha subtypes. IFN-alpha8 induced beta-R1 weakly. beta-R1 was not induced by IFN-beta in mutant cell lines U2A, U3A, U4A, and U6A, which lack, respectively, p48, STAT1, JAK1, and STAT2. U5A cells, which lack the Ifnar 2.2 component of the IFN-alpha and -beta receptor, also failed to express beta-R1. U1A cells are partially responsive to IFN-beta and IFN-alpha8 but lacked beta-R1 expression, indicating that TYK2 protein is essential for induction of this gene. Taken together, these results suggest that the expression of beta-R1 in response to type I IFN requires IFN-stimulated gene factor 3 plus an additional component, which is more efficiently formed on induction by IFN-beta compared with IFN-alpha.

  20. Incorporation of tin affects crystallization, morphology, and crystal composition of Sn-Beta

    DEFF Research Database (Denmark)

    Tolborg, Søren; Katerinopoulou, A.; Falcone, D. D.;


    The crystallization of Sn-Beta in fl uoride medium is greatly in fl uenced by the amount and type of tin source present in the synthesis gel. By varying the amount of tin in the form of tin( IV ) chloride pentahydrate, the time required for crystallization was studied. It was found that tin...... not only drastically a ff ects the time required for crystallization, but also that the presence of tin changes the morphology of the formed Sn-Beta crystals. For low amounts of tin (Si/Sn ¼ 400) crystallization occurs within four days and the Sn-Beta crystals are capped bipyramidal in shape, whereas...... to the minimum time required for obtaining full crystallinity. At excessive crystallization times, the catalytic activity decreased, presumably due to Ostwald ripening...

  1. Amyloid Beta as a Modulator of Synaptic Plasticity


    Parihar, Mordhwaj S.; Gregory J. Brewer


    Alzheimer’s disease is associated with synapse loss, memory dysfunction and pathological accumulation of amyloid beta in plaques. However, an exclusively pathological role for amyloid beta is being challenged by new evidence for an essential function of amyloid beta at the synapse. Amyloid beta protein exists in different assembly states in the central nervous system and plays distinct roles ranging from synapse and memory formation to memory loss and neuronal cell death. Amyloid beta is pres...

  2. Beta-adrenoceptors in obstetrics and gynecology. (United States)

    Modzelewska, Beata


    One hundred and twenty years after the description of extracts from the adrenal medulla, the use of beta-blockers and beta-agonists evolved from antianginal drugs and tocolytics to ligand-directed signaling. Beta-blockers in the fields of obstetrics and gynecology have so far been limited to the consideration of continuing treatment of disorders of the cardiovascular system and other dysfunctions that started before pregnancy. Studies in recent years have shown that beta-adrenoceptor signaling might be crucial in carcinogenesis and metastasis, apoptosis and anoikis. On the other hand, the use of beta-adrenoceptor agonists in tocolysis is, as yet, the primary method for inhibiting premature uterine contractions. Unfortunately, the efficacy of current pharmacological treatment for the management of preterm labor is regularly questioned. Moreover, studies related to non-pregnant myometrium performed to date indicate that the rhythmic contractions of the uterus are required for menstruation and have an important role in human reproduction. In turn, abnormal uterine contractility has been linked to dysmenorrhea, a condition associated with painful uterine cramping. The benefits of the use of beta2-adrenoceptor agonists in dysmenorrhea are still unclear and should be balanced against a wide range of adverse effects recognized with this class of medication. The ideal tocolytic agent is one which is effective for the pregnant or non-pregnant woman but has no side effects on either the woman or the baby. Looking to the future with both caution and hope, the potential metamorphosis of beta3-adrenoceptor agonists from experimental tools into therapeutic drugs for tocolysis warrants attention.

  3. Beta Gyres in Global Analysis Fields

    Institute of Scientific and Technical Information of China (English)



    A three-component decomposition is applied to global analysis data to show the existence of a beta gyre,which causes Tropical Cyclone (TC) to drift from a large-scale environmental steering current.Analyses from the Global Data Assimilation and Prediction System (GDAPS) of the Korea Meteorological Administration (KMA),the Global Forecast System (GFS) of NCEP,and the Navy Operational Global Atmospheric Prediction System (NOGAPS) are used in this study.The structure of the beta gyre obtained in our analyses is in good agreement with the theoretical structure,with a cyclonic circulation to the southwest of the TC center,an anticyclonic circulation to the northeast,and a ventilation flow directed northwestward near the center.The circulation of the beta gyre is strongest at the 850-hPa level where the cyclonically swirling primary circulation is strongest,and decreases with height,in a pyramid shape similar to the primary circulation.The individual structure of the beta gyre is case- and model-dependent.At a certain analysis time,one model may clearly reveal a well-defined beta gyre,but the other models may not.Within one model,the beta gyre may be well defined at some analysis times,but not at other times.The structure of the beta gyre in the analysis field is determined by the nature of the vortex initialization scheme and the model behavior during the 6-h forecast in the operational data assimilation cycle.

  4. [Transforming growth factor-beta controls pathogenesis of Crohn disease]. (United States)

    Friess, H; di Mola, F F; Egger, B; Scheuren, A; Kleeff, J; Zimmermann, A; Büchler, M W


    The pathogenetic mechanisms which contribute to the progression of Crohn's disease are still not known. Transforming growth factor-beta (TGF-beta) and its subtypes are multifunctional polypeptides which regulate immunological processes as well as the synthesis of the extracellular matrix and fibrogenesis. In the present study, Crohn's disease tissue samples of 18 patients undergoing intestinal resection were analyzed by Northern blot analysis, in situ hybridization and immunostaining for TGF-beta 1-3 and the TGF-beta receptors type I-III (T beta R-I, T beta R-II, T beta R-III). There was a marked overexpression of TGF-beta 1, TGF-beta 3 and T beta R-II in 94% of the Crohn's disease tissue samples. TGF-beta 2 and T beta R-I ALK5 and T beta R-III were enhanced in 72%, 72% and 82% of the Crohn tissue samples, respectively. In situ hybridization and immunostaining revealed that there was frequent coexpression of TGF-beta with its signaling receptors. Our data indicate that TGF-beta and their receptors seem to be involved in the pathogenesis of Crohn's disease. Their enhanced expression might contribute to the increase in extracellular matrix resulting in fibrosis and subsequently in intestinal obstruction.

  5. Hydrothermal synthesis of alpha- and beta-HgS nanostructures (United States)

    Galain, Isabel; María, Pérez Barthaburu; Ivana, Aguiar; Laura, Fornaro


    We synthesized HgS nanostructures by the hydrothermal method in order to use them as electron acceptors in hybrid organic-inorganic solar cells. We employed different mercury sources (HgO and Hg(CH3COO)2) and polyvinylpyrrolidone (PVP) or hexadecanethiol (HDT) as stabilizing/capping agent for controlling size, crystallinity, morphology and stability of the obtained nanostructures. We also used thiourea as sulfur source, and a temperature of 180 °C during 6 h. Synthesized nanostructures were characterized by powder X-Ray Diffraction, Diffuse Reflectance Infrared Fourier Transform and Transmission Electron Microscopy. When PVP acts as stabilizing agent, the mercury source has influence on the size -but not in morphology- of the beta-HgS obtained nansostructures. HDT has control over nanostructures' size and depending on the relation Hg:HDT, we obtained a mixture of alpha and beta HgS which can be advantageous in the application in solar cells, due their absorption in different spectral regions. The smallest nanostructures obtained have a mean diameter of 20 nm when using HDT as capping agent. Also, we deposited the aforementioned nanostructures onto flat glass substrates by the spin coating technique as a first approach of an active layer of a solar cell. The depositions were characterized by atomic force microscopy. We obtained smaller particle deposition and higher particle density -but a lower area coverage (5%) - in samples with HDT as capping agent. This work presents promising results on nanostructures for future application on hybrid solar cells. Further efforts will be focused on the deposition of organic-inorganic layers.

  6. In vitro reprogramming of pancreatic alpha cells towards a beta cell phenotype following ectopic HNF4α expression. (United States)

    Sangan, Caroline B; Jover, Ramiro; Heimberg, Harry; Tosh, David


    There is currently a shortage of organ donors available for pancreatic beta cell transplantation into diabetic patients. An alternative source of beta cells is pre-existing pancreatic cells. While we know that beta cells can arise directly from alpha cells during pancreatic regeneration we do not understand the molecular basis for the switch in phenotype. The aim of the present study was to investigate if hepatocyte nuclear factor 4 alpha (HNF4α), a transcription factor essential for a normal beta cell phenotype, could induce the reprogramming of alpha cells towards potential beta cells. We utilised an in vitro model of pancreatic alpha cells, the murine αTC1-9 cell line. We initially characterised the αTC1-9 cell line before and following adenovirus-mediated ectopic expression of HNF4α. We analysed the phenotype at transcript and protein level and assessed its glucose-responsiveness. Ectopic HNF4α expression in the αTC1-9 cell line induced a change in morphology (1.7-fold increase in size), suppressed glucagon expression, induced key beta cell-specific markers (insulin, C-peptide, glucokinase, GLUT2 and Pax4) and pancreatic polypeptide (PP) and enabled the cells to secrete insulin in a glucose-regulated manner. In conclusion, HNF4α reprograms alpha cells to beta-like cells.

  7. Synchronized Beta-Band Oscillations in a Model of the Globus Pallidus-Subthalamic Nucleus Network under External Input (United States)

    Ahn, Sungwoo; Zauber, S. Elizabeth; Worth, Robert M.; Rubchinsky, Leonid L.


    Hypokinetic symptoms of Parkinson's disease are usually associated with excessively strong oscillations and synchrony in the beta frequency band. The origin of this synchronized oscillatory dynamics is being debated. Cortical circuits may be a critical source of excessive beta in Parkinson's disease. However, subthalamo-pallidal circuits were also suggested to be a substantial component in generation and/or maintenance of Parkinsonian beta activity. Here we study how the subthalamo-pallidal circuits interact with input signals in the beta frequency band, representing cortical input. We use conductance-based models of the subthalamo-pallidal network and two types of input signals: artificially-generated inputs and input signals obtained from recordings in Parkinsonian patients. The resulting model network dynamics is compared with the dynamics of the experimental recordings from patient's basal ganglia. Our results indicate that the subthalamo-pallidal model network exhibits multiple resonances in response to inputs in the beta band. For a relatively broad range of network parameters, there is always a certain input strength, which will induce patterns of synchrony similar to the experimentally observed ones. This ability of the subthalamo-pallidal network to exhibit realistic patterns of synchronous oscillatory activity under broad conditions may indicate that these basal ganglia circuits are directly involved in the expression of Parkinsonian synchronized beta oscillations. Thus, Parkinsonian synchronized beta oscillations may be promoted by the simultaneous action of both cortical (or some other) and subthalamo-pallidal network mechanisms. Hence, these mechanisms are not necessarily mutually exclusive. PMID:28066222

  8. Detrimental effects of beta-blockers in COPD - A concern for nonselective beta-blockers

    NARCIS (Netherlands)

    van der Woude, HJ; Zaagsma, J; Postma, DS; Winter, TH; van Hulst, M; Aalbers, R


    Introduction: beta-Blockers are known to worsen FEV1 and airway hyperresponsiveness (AHR) in patients with asthma. Both characteristics determine the outcome of COPD, a disease with frequent cardiac comorbidity requiring beta-blocker treatment. Design: A double-blind, placebo-controlled, randomized,

  9. Beta decay of the M{sub T}=-1 nucleus {sup 58}Zn studied by selective laser ionization

    Energy Technology Data Exchange (ETDEWEB)

    Jokinen, A.; Aeystoe, J. [Jyvaeskylae Univ. (Finland). Dept. of Physics; Oinonen, M. [Jyvaeskylae Univ. (Finland). Dept. of Physics]|[EP Division, CERN, CH-1211 Geneve 23 (Switzerland)] [and others; ISOLDE Collaboration


    Beta decay of {sup 58}Zn has been studied for the first time. A new laser ion-source concept has been used to produce mass-separated sources for beta and gamma spectroscopy. The half-life of {sup 58}Zn was determined to be 86(18) ms. Comparisons are made with previous data from charge-exchange reactions. Our Gamow-Teller strength to the 1{sup +} state at 1051 keV excitation in {sup 58}Cu agrees well with the value extracted from a recent ({sup 3}He,t) study. Extensive shell-model calculations are presented. (orig.) With 7 figs., 2 tabs., 33 refs.

  10. Betavoltaic Prediction using Ni-63 beta radioisotope and Semiconductor

    Energy Technology Data Exchange (ETDEWEB)

    Jung, H. K.; Lee, N. H.; Joo, Y. S.; Cheong, Y. M. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)


    Micro-electromechanical Systems (MEMS) comprise a rapidly expanding research field with potential applications varying from sensors to more recent optical applications. Depending on the application, these devices often require an onboard power source for remote operation, especially in medical cases requiring operation for an extended period of time. Suggested power sources include fuel cells and solar energy, but nuclear power sources may provide significant advantages for certain applications. Hence, the objective of this study is to establish the feasibility of nuclear sources (beta and alpha particles) for supplying a power to realistic MEMS devices. The betavoltaic effect is the generation of potential due to net positive charge flow of the electron-induced electron-hole production (EHP). When EHPs diffuse into the depletion region of the semiconductor pn-junction, the electrical field of the depletion region sweeps them across the depletion region. Because the resulting current is from n-type to p-type semiconductor, net power can be extracted.

  11. Field transportable beta spectrometer. Innovative technology summary report

    Energy Technology Data Exchange (ETDEWEB)



    The objective of the Large-Scale Demonstration Project (LSDP) is to select and demonstrate potentially beneficial technologies at the Argonne National Laboratory-East (ANL) Chicago Pile-5 Test Reactor (CP-5). The purpose of the LSDP is to demonstrate that by using innovative and improved deactivation and decommissioning (D and D) technologies from various sources, significant benefits can be achieved when compared to baseline D and D technologies. One such capability being addressed by the D and D Focus Area is rapid characterization for facility contaminants. The technology was field demonstrated during the period January 7 through January 9, 1997, and offers several potential benefits, including faster turn-around time, cost reduction, and reduction in secondary waste. This report describes a PC controlled, field-transportable beta counter-spectrometer which uses solid scintillation coincident counting and low-noise photomultiplier tubes to count element-selective filters and other solid media. The dry scintillation counter used in combination with an element-selective technology eliminates the mess and disposal costs of liquid scintillation cocktails. Software in the instrument provides real-time spectral analysis. The instrument can detect and measure Tc-99, Sr-90, and other beta emitters reaching detection limits in the 20 pCi range (with shielding). Full analysis can be achieved in 30 minutes. The potential advantages of a field-portable beta counter-spectrometer include the savings gained from field generated results. The basis for decision-making is provided with a rapid turnaround analysis in the field. This technology would be competitive with the radiometric analysis done in fixed laboratories and the associated chain of custody operations.

  12. Measurement of the beta-neutrino correlation in laser trapped {sup 21}Na

    Energy Technology Data Exchange (ETDEWEB)

    Scielzo, Nicholas David


    Trapped radioactive atoms are an appealing source for precise measurements of the beta-neutrino correlation coefficient, a, since the momentum of the neutrino can be inferred from the detection of the unperturbed low-energy recoil daughter nucleus. Sodium-21 is produced on-line at the 88'' cyclotron at Lawrence Berkeley National Laboratory, and 8e5 atoms have been maintained in a magneto-optical trap. A static electric field draws daughter Neon-21 ions to a microchannel plate detector and betas are detected in coincidence with a plastic scintillator beta detector. The Neon-21 time-of-flight distribution determines the beta neutrino correlation coefficient, a. The resulting charge-state distribution is compared to a simple model based on the sudden approximation which suggests a small but important contribution from nuclear recoil-induced ionization. A larger than expected fraction of the daughters are detected in positive charge-states, but no dependence on either the beta or recoil nucleus energy was observed. We find a = 0.5243 plus or minus 0.0092, which is in 3.6 sigma disagreement with the Standard Model prediction of a = 0.559 plus or minus 0.003. Aside from a deviation from the Standard Model, a possible explanation for the discrepancy is that the branching ratio to the first excited state is in error.

  13. Decreased beta-band activity is correlated with disambiguation of hidden figures. (United States)

    Minami, Tetsuto; Noritake, Yosuke; Nakauchi, Shigeki


    Insight is commonly described as sudden comprehension, sometimes called an "Aha! moment." In everyday life, we apply the process of insight to problems that are difficult to solve at first glance or that we perceive as ambiguous; however the brain dynamics underlying the disambiguation process remains elusive. Beta-band oscillatory brain activity has been hypothesized to reflect the transition of cognitive states. To elucidate the neural mechanism of insight, we recorded electroencephalograms while subjects were presented with hidden figures followed by unambiguous, gray images. We identified oscillatory activity to detect temporal changes, and compared brain activity that occurred during a perceptual transition with activity that occurred when no perceptual transition occurred. Statistical comparison confirmed stronger beta-power decrease during perceptual transition. Source analysis indicated that the beta-power decrease was around the parietal-posterior regions, mainly in the precuneus. We propose that beta-band desynchronization in the parietal-posterior regions reflects the disambiguation process, and our findings provide additional support for the theory that beta-band activity is related to the transition of cognitive state.

  14. Mechanical design and analysis for a low beta squeezed half-wave resonator

    CERN Document Server

    He, Shoubo; Zhang, Shenghu; Yue, Weiming; Zhang, Cong; Wang, Zhijun; Wang, Ruoxu; Xu, Mengxin; Huang, Shichun; Huang, Yulu; Jiang, Tiancai; Wang, Fengfeng; Zhang, Shengxue; Zhao, Hongwei


    A superconducting half-wave resonator (HWR) of frequency=162.5 MHz and {\\beta}=0.09 has been developed at Institute of Modern Physics. Mechanical stability of the low beta HWR cavity is a big challenge in cavity design and optimization. The mechanical deformations of a radio frequency superconducting cavity could be a source of instability, both in continues wave(CW) operation or in pulsed mode. Generally, the lower beta cavities have stronger Lorentz force detuning than that of the higher beta cavities. In this paper, a basic design consideration in the stiffening structure for the detuning effect caused by helium pressure and Lorentz force has been presented. The mechanical modal analysis has been investigated with finite element method(FEM). Based on these considerations, a new stiffening structure has been promoted for the HWR cavity. The computation results concerning the frequency shift show that the low beta HWR cavity with new stiffening structure has low frequency sensitivity coefficient, Lorentz for...

  15. Measurement of the beta-neutrino correlation in laser trapped 21Na

    Energy Technology Data Exchange (ETDEWEB)

    Scielzo, Nicholas David [Univ. of California, Berkeley, CA (United States)


    Trapped radioactive atoms are an appealing source for precise measurements of the beta-neutrino correlation coefficient, a, since the momentum of the neutrino can be inferred from the detection of the unperturbed low-energy recoil daughter nucleus. Sodium-21 is produced on-line at the 88'' cyclotron at Lawrence Berkeley National Laboratory, and 8e5 atoms have been maintained in a magneto-optical trap. A static electric field draws daughter Neon-21 ions to a microchannel plate detector and betas are detected in coincidence with a plastic scintillator beta detector. The Neon-21 time-of-flight distribution determines the beta neutrino correlation coefficient, a. The resulting charge-state distribution is compared to a simple model based on the sudden approximation which suggests a small but important contribution from nuclear recoil-induced ionization. A larger than expected fraction of the daughters are detected in positive charge-states, but no dependence on either the beta or recoil nucleus energy was observed. We find a = 0.5243 plus or minus 0.0092, which is in 3.6 sigma disagreement with the Standard Model prediction of a = 0.559 plus or minus 0.003. Aside from a deviation from the Standard Model, a possible explanation for the discrepancy is that the branching ratio to the first excited state is in error.

  16. Characterization of large area ZnS(Ag) detector for gross alpha and beta activity measurements in tap water plants

    Energy Technology Data Exchange (ETDEWEB)

    Lunardon, M.; Cester, D.; Mistura, G.; Moretto, S.; Stevanato, L.; Viesti, G. [Department of Physics and Astronomy ' Galileo Galilei' , University of Padova, (Italy); Schotanus, P.; Bodewits, E. [SCIONIX Holland BV, (Netherlands)


    In this work we present the characterization of a large area 200 x 200 mm{sup 2} EJ-444 scintillation detector to be used for monitoring gross alpha and beta activity in tap water plants. Specific tests were performed to determine the best setup to readout the light from the detector side in order to have the possibility to stack many detectors and get a compact device with total active area of the order of 1 m{sup 2}. Alpha/Beta discrimination, efficiency and homogeneity tests were carried out with alpha and beta sources. Background from ambient radioactivity was measured as well. Alpha/beta real-time monitoring in drinking water is a goal of the EU project TAWARA{sub R}TM. (authors)

  17. NADPH-dependent glutamate dehydrogenase in Penicillium chrysogenum is involved in regulation of beta-lactam production

    DEFF Research Database (Denmark)

    Thykær, Jette; Kildegaard, Kanchana Rueksomtawin; Noorman, H.


    The interactions between the ammonium assimilatory pathways and beta-lactam production were investigated by disruption of the NADPH-dependent glutamate dehydrogenase gene (gdhA) in two industrial beta-lactam-producing strains of Penicillium chrysogenum. The strains used were an adipoyl-7-ADCA......- and a penicillin-producing strain. The gdhA gene disruption caused a decrease in maximum specific growth rate of 26 % and 35 % for the adipoyl-7-ADCA-producing strain and the penicillin-producing strain, respectively, compared to the corresponding reference strains. Interestingly, no beta-lactam production...... was detected in either of the Delta gdhA strains. Supplementation with glutamate restored growth but no beta-lactam production was detected for the constructed strains. Cultures with high ammonium concentrations (repressing conditions) and with proline as nitrogen source (de-repressed conditions) showed...

  18. Patterns of alpha, beta and gamma diversity of the herpetofauna in Mexico’s Pacific lowlands and adjacent interior valleys

    Directory of Open Access Journals (Sweden)

    García, A.


    Full Text Available The latitudinal distribution patterns of alpha, beta and gamma diversity of reptiles, amphibians and herpetofauna were analyzed using individual binary models of potential distribution for 301 species predicted by ecological modelling for a grid of 9,932 quadrants of ~25 km2 each. We arranged quadrants in 312 latitudinal bands in which alpha, beta and gamma values were determined. Latitudinal trends of all scales of diversity were similar in all groups. Alpha and gamma responded inversely to latitude whereas beta showed a high latitudinal fluctuation due to the high number of endemic species. Alpha and gamma showed a strong correlation in all groups. Beta diversity is an important component of the herpetofauna distribution patterns as a continuous source of species diversity throughout the region.

  19. Beta decay of {sup 103}Sn

    Energy Technology Data Exchange (ETDEWEB)

    Kavatsyuk, O.; Kavatsyuk, M. [GSI, Darmstadt (Germany); National Taras Shevcjenko Univ. of Kyiv (Australia); Batist, L. [St. Petersburg Nuclear Physics Inst. (Russian Federation); Univ. di Napoli (Italy); INFN, Napoli (Italy); Banu, A.; Becker, F.; Bruechle, W.; Doering, J.; Gorska, M.; Grawe, H.; Kirchner, R.; Mandal, S.; Mazzocchi, C.; Plettner, C.; Roeckl, E.; Schaedel, M. [GSI, Darmstadt (Germany); Blazhev, A. [GSI, Darmstadt (Germany); Univ. Sofia (Bulgaria); Faestermann, T. [Technische Universitaet Muenchen (Germany); Janas, Z.; Karny, M.; Plochocki, A.; Zylicz, J. [University of Warsaw (Poland); Jungclaus, A. [Universidad Autonoma de Madrid, Departamento de Fisica Teorica (Spain); La Commara, M.; Romoli, M. [INFN, Napoli (Italy); Mukha, I. [GSI, Darmstadt (Germany); Kurchatov Inst. Moscow (Russian Federation); Muralithar, S. [GSI, Darmstadt (Germany); Forschungszentrum Rossendorf (Germany); Schwengner, R. [Forschungszentrum Rossendorf (Germany)


    The {beta} decay of {sup 103}Sn, a three-neutron-particle nucleus with respect to the {sup 100}Sn core, was investigated at the GSI on-line mass separator using an array of 17 germanium crystals and a total absorption spectrometer. A total of 31 {beta}-delayed {gamma}-rays (29 new) of the {sup 103}Sn{yields}{sup 103}In decay were observed and, on the basis of {beta}-{gamma}-{gamma} coincidences, the {sup 103}Sn decay scheme was established for the first time. By means of total absorption spectroscopy, {beta} intensities, the Gamow-Teller strength distribution and the summed Gamow-Teller strength value of 3.5{+-}0.5 were determined for this decay. Its half-life and Q{sub EC} value were found to be 7.0{+-}0.2 s and 7.64{+-}0.7 MeV, respectively. The {beta}-delayed proton branching ratio was measured to be 1.2{+-}0.1%. The results are discussed in comparison with shell-model predictions based on realistic and empirical interactions. (orig.)

  20. Crowd Sourcing. (United States)

    Baum, Neil


    The Internet has contributed new words and slang to our daily vernacular. A few terms, such as tweeting, texting, sexting, blogging, and googling, have become common in most vocabularies and in many languages, and are now included in the dictionary. A new buzzword making the rounds in industry is crowd sourcing, which involves outsourcing an activity, task, or problem by sending it to people or groups outside a business or a practice. Crowd sourcing allows doctors and practices to tap the wisdom of many instead of relying only on the few members of their close-knit group. This article defines "crowd sourcing," offers examples, and explains how to get started with this approach that can increase your ability to finish a task or solve problems that you don't have the time or expertise to accomplish.

  1. Beta-thalassemia and beta[A] globin gene haplotypes in Mexican mestizos. (United States)

    Villalobos-Arámbula, A R; Bustos, R; Casas-Castañeda, M; Gutiérrez, E; Perea, F J; Thein, S L; Ibarra, B


    B-globin haplotypes of 20 beta-thalassemia (beta-thal) and 87 beta(A) Mexican mestizo chromosomes were analyzed to ascertain the origin of the beta-thal alleles and the frequencies and distribution of the beta(A) haplotypes among northwestern Mexican mestizos. Sixteen beta-thal chromosomes carried six Mediterranean alleles [five codon 39 C-->T; two IVS1:1 G-->A; two IVS1:5 G-->A; three IVS1:110 G(A; one codon 11 (-T) and three (deltabeta)zero-thal]; the remaining four were linked to three rare alleles (two -28 A-->C and one each: -87 C-->T and initiation codon ATG-->GTG). Among the 87 beta(A) chromosomes, 17 different 5' haplotypes with frequencies for 1, 3, 2 and 5 of 39.0%, 17. 2%, 9.2% and 6.9%, respectively, were observed. The beta-haplotype analysis showed that 13 out of 16 Mediterranean chromosomes could easily be explained by gene migration; however, one codon 39 associated with haplotype 4 (----+ +-), one IVS1:1 with haplotype 1(+----++) and one IVS1:5 G-->A, may represent separate mutational events. Analysis of the rare alleles showed that the -28 A-->C mutation was associated with the commonest beta(A) haplotype in Mexican mestizos, Mediterraneans and the total world population; therefore an independent origin cannot be ruled out. The -87 C-->T and initiation codon ATG-->GTG were found with beta-haplotypes different from the reported ones, suggesting an indigenous origin.

  2. Determination of differential dose rates in a mixed beta and gamma field using shielded Al2O3:C : Results of Monte Carlo modelling

    DEFF Research Database (Denmark)

    Aznar, M.C.; Nathan, R.; Murray, A.S.


    Mixed beta and gamma heterogeneous radiation fields are found in many circumstances, ranging from retrospective dosimetry to medical therapy treatments. It can be very important to provide a direct measurement of the contribution to dose rate from beta particles and gamma rays separately, especia...... the sensitivity of the response to the different beta and gamma contributions from uranium, thorium and potassium sources. (C) 2003 Elsevier Science Ltd. All rights reserved....

  3. Absolute measurement of {beta} emitters with a 4 {pi} counter; Mesure absolue des emetteurs {beta} au compteur 4 {pi}

    Energy Technology Data Exchange (ETDEWEB)

    Le Gallic, Y. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires


    The object of this work is to investigate the conditions under which the activity of {beta}-emitting radionuclides may be measured with a maximum of precision, and as a result to study the relevant corrections. The various problems relating to activity measurements with a 4 {pi} counter have been examined successively: - comparison of 4 {pi}, GM and proportional counters; - study of the preparation of sources; - corrections on the counting of sources; - self-absorption; - correction for absorption. The precision obtained on these measurements varies from 1.2 to 3 per cent, with the result that the 4 {pi} counter can be considered a very satisfactory calibration instrument. (author) [French] Le but de ce travail est de rechercher les conditions permettant d'obtenir avec le maximum de precision, la mesure de l'activite des radionuclides se desintegrant par emission et par consequent d'etudier les corrections qui s'y rapportent. Nous avons examine successivement les differents problemes se rapportant aux mesures d'activite au compteur 4 {pi}: - Comparaison des compteurs 4 {pi}, GM et proportionnel; - etude de la preparation des sources; - corrections sur la numeration des sources; - auto-absorption; - correction d'absorption. La precision obtenue dans ces mesures, variant de 1,2 a 3 pour cent, on peut donc considerer le compteur 4 {pi} comme un instrument d'etalonnage tres satisfaisant. (auteur)

  4. Beta-decay, Bremsstrahlen, and the origin of molecular chirality (United States)

    Bonner, W. A.; Yi, L.


    A brief review is presented of the Vester-Ulbricht beta-decay Bremsstrahlen hypothesis for the origin of optical activity, and of subsequent experiments designed to test it. Certain experiments along these lines, begun in 1974 and involving the irradiation of racemic and optically active amino acids in a 61.7 KCi Sr-90-Y-90 Bremsstrahlen source, have now been completed and are described. After 10.89 years of irradiation with a total Bremsstrahlen dose of 2.5 x 10 to the 9th rads, crystalline DL-leucine, norleucine, and norvaline suffered 47.2, 33.6, and 27.4 percent radiolysis, respectively, but showed no evidence whatsoever of asymmetric degradation. Dand L-Leucine underwent about 48 percent radiolysis and showed 2.4-2.9 percent radioracemization. Other samples in solution were too severely degraded to analyze. Probable intrinsic reasons for the failure of the Vester-Ulbricht mechanism to afford asymmetric radiolysis in the present and related experiments involving beta-decay Bremsstrahlen are enumerated.

  5. Reduced beta band connectivity during number estimation in autism

    Directory of Open Access Journals (Sweden)

    Katrin A. Bangel


    Full Text Available Recent evidence suggests that disruption of integrative processes in sensation and perception may play a critical role in cognitive and behavioural atypicalities characteristic of ASD. In line with this, ASD is associated with altered structural and functional brain connectivity and atypical patterns of inter-regional communication which have been proposed to contribute to cognitive difficulties prevalent in this group. The present MEG study used atlas-guided source space analysis of inter-regional phase synchronization in ASD participants, as well as matched typically developing controls, during a dot number estimation task. This task included stimuli with globally integrated forms (animal shapes as well as randomly-shaped stimuli which lacked a coherent global pattern. Early task-dependent increases in inter-regional phase synchrony in theta, alpha and beta frequency bands were observed. Reduced long-range beta-band phase synchronization was found in participants with ASD at 70–145 ms during presentation of globally coherent dot patterns. This early reduction in task-dependent inter-regional connectivity encompassed numerous areas including occipital, parietal, temporal, and frontal lobe regions. These results provide the first evidence for inter-regional phase synchronization during numerosity estimation, as well as its alteration in ASD, and suggest that problems with communication among brain areas may contribute to difficulties with integrative processes relevant to extraction of meaningful ‘Gestalt’ features in this population.

  6. Reduced beta band connectivity during number estimation in autism. (United States)

    Bangel, Katrin A; Batty, Magali; Ye, Annette X; Meaux, Emilie; Taylor, Margot J; Doesburg, Sam M


    Recent evidence suggests that disruption of integrative processes in sensation and perception may play a critical role in cognitive and behavioural atypicalities characteristic of ASD. In line with this, ASD is associated with altered structural and functional brain connectivity and atypical patterns of inter-regional communication which have been proposed to contribute to cognitive difficulties prevalent in this group. The present MEG study used atlas-guided source space analysis of inter-regional phase synchronization in ASD participants, as well as matched typically developing controls, during a dot number estimation task. This task included stimuli with globally integrated forms (animal shapes) as well as randomly-shaped stimuli which lacked a coherent global pattern. Early task-dependent increases in inter-regional phase synchrony in theta, alpha and beta frequency bands were observed. Reduced long-range beta-band phase synchronization was found in participants with ASD at 70-145 ms during presentation of globally coherent dot patterns. This early reduction in task-dependent inter-regional connectivity encompassed numerous areas including occipital, parietal, temporal, and frontal lobe regions. These results provide the first evidence for inter-regional phase synchronization during numerosity estimation, as well as its alteration in ASD, and suggest that problems with communication among brain areas may contribute to difficulties with integrative processes relevant to extraction of meaningful 'Gestalt' features in this population.

  7. Gestalt perception is associated with reduced parietal beta oscillations. (United States)

    Zaretskaya, Natalia; Bartels, Andreas


    The ability to perceive composite objects as a whole is fundamental for visual perception in a complex and cluttered natural environment. This ability may be mediated by increased communication between neural representations of distinct object elements, and has been linked to increased synchronization of oscillatory brain activity in the gamma band. Previous studies of perceptual grouping either guided attention between local and global aspects of a given stimulus or manipulated its physical properties to achieve grouped and ungrouped perceptual conditions. In contrast to those studies, we fully matched the physical properties underlying global and local percepts using a bistable stimulus that causes the viewer to perceive either local motion of multiple elements or global motion of two illusory shapes without any external change. To test the synchronization hypothesis we recorded brain activity with EEG, while human participants viewed the stimulus and reported changes in their perception. In contrast to previous findings we show that power of the beta-band was lower during perception of global Gestalt than during that of local elements. Source localization places these differences in the posterior parietal cortex, overlapping with a site previously associated with both attention and Gestalt perception. These findings reveal a role of parietal beta-band activity in internally, rather than externally or attention-driven processes of Gestalt perception. They also add to the growing evidence for shared neural substrates of attention and Gestalt perception, both being linked to parietal cortex.

  8. 2MTF V. Cosmography, Beta, and the residual bulk flow

    CERN Document Server

    Springob, Christopher M; Staveley-Smith, Lister; Masters, Karen L; Macri, Lucas M; Koribalski, Baerbel S; Jones, D Heath; Jarrett, Tom H; Magoulas, Christina; Erdogdu, Pirin


    Using the Tully-Fisher relation, we derive peculiar velocities for the 2MASS Tully-Fisher Survey and describe the velocity field of the nearby Universe. We use adaptive kernel smoothing to map the velocity field, and compare it to reconstructions based on the redshift space galaxy distributions of the 2MASS Redshift Survey (2MRS) and the IRAS Point Source Catalog Redshift Survey (PSCz). With a standard $\\chi^2$ minimization fit to the models, we find that the PSCz model provides a better fit to the 2MTF velocity field data than does the 2MRS model, and provides a value of $\\beta$ in greater agreement with literature values. However, when we subtract away the monopole deviation in the velocity zeropoint between data and model, the 2MRS model also produces a value of $\\beta$ in agreement with literature values. We also calculate the `residual bulk flow': the component of the bulk flow not accounted for by the models. This is $\\sim 250$ km/s when performing the standard fit, but drops to $\\sim 150$ km/s for both...

  9. Beta-asymmetry studies on polarized {sup 82}Rb atoms in a TOP trap

    Energy Technology Data Exchange (ETDEWEB)

    Hausmann, M. [Isotope and Nuclear Chemistry, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)]. E-mail: hausmann@LANL.GOV; Vieira, D.J. [Isotope and Nuclear Chemistry, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Wu, J. [Isotope and Nuclear Chemistry, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Zhao, X. [Isotope and Nuclear Chemistry, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Boulay, M.G. [Neutron Science and Technology, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Hime, A. [Neutron Science and Technology, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)


    Atoms of {sup 82}Rb (t{sub 1/2} = 76 s) confined in a time-orbiting-potential (TOP) magnetic trap make a favorable source for {beta}-asymmetry studies by providing an essentially massless source of highly polarized atoms. An offline mass separator is coupled to a double magneto-optical trap (MOT) and TOP trap system. Once in the TOP trap the magnetic trap's rotating bias field defines the polarization axis and allows one to measure the correlation between the nuclear spin direction and the {beta} emission direction using a single positron detector. A proof-of-principle experiment using this method has demonstrated that the parity violating ({beta}->-bar J->) correlation can be studied. Here we outline improvements to the experiment with the goal of a 1% measurement of the {beta}-asymmetry correlation parameter A in the Gamow-Teller decay of {sup 82}Rb which in the semi-leptonic sector would pose a competitive test of the Standard Model.

  10. Alpha and beta particle induced scintillations in liquid and solid neon

    CERN Document Server

    Michniak, R A; McKinsey, D N; Doyle, J M


    Scintillations induced by alpha and beta particles in liquid and solid neon are studied and their light yield measured. Charged particle scintillation in neon is primarily in the extreme ultraviolet (EUV). We detect this EUV light by converting it to blue using a wavelength shifting fluor and detecting the blue light with a photomultiplier tube. It is observed that liquid neon is a somewhat less-efficient scintillator than liquid helium for both alpha and beta radiation while the light yield in solid neon is greater than in liquid helium. Based on our measurements of the relative light yields of liquid and solid neon to liquid helium whose absolute light yield has previously been determined, we find that an alpha source in liquid neon produces up to 5900 photons per MeV while a beta source produces up to 7400 photons per MeV. In solid neon, we find that an alpha particle produces up to 9300 photons per MeV while a beta particle produces up to 17,000 photons per MeV. We observe a significant dependence of the ...

  11. Beta decay of {sup 61}Ga

    Energy Technology Data Exchange (ETDEWEB)

    Oinonen, M.; Dendooven, P.; Jokinen, A.; Penttilae, H.; Aeystoe, J. [Jyvaeskylae Univ. (Finland). Dept. of Physics; Baumann, P.; Knipper, A.; Ramdhane, M.; Walter, G. [Institut de Recherches Subatomiques, F-67037 Strasbourg (France); Fujita, Y. [Department of Physics, Osaka University, Toyonaka, Osaka 560-0043 (Japan); Gorska, M.; Grawe, H.; Hu, Z.; Kirchner, R.; Klepper, O.; Liu, W.; Roeckl, E. [Gesellschaft fuer Schwerionenforschung, Postfach 110552, D-64220 Darmstadt (Germany); Janas, Z.; Plochocki, A. [Institute of Experimental Physics, Warsaw University, PL-00681 Warsaw (Poland)


    The {beta} decay of {sup 61}Ga to its mirror nucleus {sup 61}Zn has been measured for the first time by using on-line mass separation and {beta}-delayed gamma-ray spectroscopy. The observed decay strength to the ground state implies superallowed character in accordance with the systematics of the mirror decays in the sd and fp shell. The {beta} feedings observed to four excited states in {sup 61}Zn are consistent with earlier spin-parity assignments based on in-beam experiments. The ground-state spin and parity for {sup 61}Ga were determined to be 3/2{sup -}. (orig.) With 3 figs., 2 tabs., 37 refs.

  12. Neutrinoless double beta decay from lattice QCD

    CERN Document Server

    Nicholson, Amy; Chang, Chia Cheng; Clark, M A; Joo, Balint; Kurth, Thorsten; Rinaldi, Enrico; Tiburzi, Brian; Vranas, Pavlos; Walker-Loud, Andre


    While the discovery of non-zero neutrino masses is one of the most important accomplishments by physicists in the past century, it is still unknown how and in what form these masses arise. Lepton number-violating neutrinoless double beta decay is a natural consequence of Majorana neutrinos and many BSM theories, and many experimental efforts are involved in the search for these processes. Understanding how neutrinoless double beta decay would manifest in nuclear environments is key for understanding any observed signals. In these proceedings we present an overview of a set of one- and two-body matrix elements relevant for experimental searches for neutrinoless double beta decay, describe the role of lattice QCD calculations, and present preliminary lattice QCD results.

  13. Fracture source

    Directory of Open Access Journals (Sweden)


    Full Text Available The fracture properties of many different types of fibers are covered in a timely new book that will prove to be a tremendous source of information and references for researchers in the wide and diverse field of fibers and composites, says Bill Clegg.

  14. BETASCAN: probable beta-amyloids identified by pairwise probabilistic analysis.

    Directory of Open Access Journals (Sweden)

    Allen W Bryan


    Full Text Available Amyloids and prion proteins are clinically and biologically important beta-structures, whose supersecondary structures are difficult to determine by standard experimental or computational means. In addition, significant conformational heterogeneity is known or suspected to exist in many amyloid fibrils. Recent work has indicated the utility of pairwise probabilistic statistics in beta-structure prediction. We develop here a new strategy for beta-structure prediction, emphasizing the determination of beta-strands and pairs of beta-strands as fundamental units of beta-structure. Our program, BETASCAN, calculates likelihood scores for potential beta-strands and strand-pairs based on correlations observed in parallel beta-sheets. The program then determines the strands and pairs with the greatest local likelihood for all of the sequence's potential beta-structures. BETASCAN suggests multiple alternate folding patterns and assigns relative a priori probabilities based solely on amino acid sequence, probability tables, and pre-chosen parameters. The algorithm compares favorably with the results of previous algorithms (BETAPRO, PASTA, SALSA, TANGO, and Zyggregator in beta-structure prediction and amyloid propensity prediction. Accurate prediction is demonstrated for experimentally determined amyloid beta-structures, for a set of known beta-aggregates, and for the parallel beta-strands of beta-helices, amyloid-like globular proteins. BETASCAN is able both to detect beta-strands with higher sensitivity and to detect the edges of beta-strands in a richly beta-like sequence. For two proteins (Abeta and Het-s, there exist multiple sets of experimental data implying contradictory structures; BETASCAN is able to detect each competing structure as a potential structure variant. The ability to correlate multiple alternate beta-structures to experiment opens the possibility of computational investigation of prion strains and structural heterogeneity of amyloid

  15. Synthesis of {beta}-haloacids by radiation

    Energy Technology Data Exchange (ETDEWEB)

    Albarran, G.; Negron-Mendoza, A. [Instituto de Ciencias y Artes, Chiapas (Mexico). Escuela de Biologia


    Hydrogen halides add to alkenes yielding the corresponding haloalkane. The addition of HX ordinally follows the course of Markownikoff`s rule. In this paper we analyze the HBr addition reaction to unsaturated carboxylic acids. The course of the addition is anti-Markownikoff. This implies that the reaction goes through free radical mechanism and the haloacid formed is in the {beta}-position. The acids under study are fumaric, itaconic, citraconic acids and the methyl ester of fumaric acid. The {beta}-haloacids formed are easily purified from the bulk solutions. (author).

  16. Volume Effects in Discrete beta functions

    CERN Document Server

    Liu, Yuzhi; Zou, Haiyuan


    We calculate discrete beta functions corresponding to the two-lattice matching for the 2D O(N) models and Dyson's hierarchical model. We describe and explain finite-size effects such as the appearance of a nontrivial infrared fixed point that goes to infinity at infinite volume or the merging of an infrared and an ultraviolet fixed point. We present extensions of the RG flows to the complex coupling plane. We discuss the possibility of constructing a continuous beta function from the discrete one by using functional conjugation methods. We briefly discuss the relevance of these findings for the search of nontrivial fixed points in multiflavor lattice gauge theory models.

  17. American ginseng modulates pancreatic beta cell activities

    Directory of Open Access Journals (Sweden)

    Luo Luguang


    Full Text Available Abstract The mechanism of the beneficial effects of Panax quinquefolius (Xiyangshen, American ginseng on diabetes is yet to be elucidated. Recent studies show that Panax quinquefolius increases insulin production and reduces the death of pancreatic beta cells. Mechanism studies indicate that Panax quinquefolius improves cell's immuno-reactivity and mitochondrial function through various factors. Clinical studies show that Panax quinquefolius improves postprandial glycemia in type 2 diabetic patients. Further studies to identify the component(s of Panax quinquefolius linked with pancreatic islets/beta cells in vitro and in vivo are warranted for better understanding of the full effects of Panax quinquefolius.

  18. The NEXT double beta decay experiment (United States)

    Laing, A.; NEXT Collaboration


    NEXT (Neutrino Experiment with a Xenon TPC) is a neutrinoless double-beta (ββ0v) decay experiment at Laboratorio Subterraneo de Canfranc (LSC). It is an electroluminescent Time Projection Chamber filled with high pressure 136Xe gas with separated function capabilities for calorimetry and tracking. Energy resolution and background suppression are the two key features of any neutrinoless double beta decay experiment. NEXT has both good energy resolution (review NEXT R&D results, the status of detector commissioning at LSC and the NEXT physics case.

  19. Helicity and nuclear $\\beta$ decay correlations

    CERN Document Server

    Hong, Ran; García, Alejandro


    We present simple derivations of nuclear $\\beta$-decay correlations with an emphasis on the special role of helicity. This provides a good opportunity to teach students about helicity and chirality in particle physics through exercises using simple aspects of quantum mechanics. In addition, this paper serves as an introduction to nuclear $\\beta$-decay correlations from both a theoretical and experimental vantage. This article can be used to introduce students to ongoing experiments searching for hints of new physics in the low-energy precision frontier.

  20. Simulated progress in double-beta decay

    Energy Technology Data Exchange (ETDEWEB)

    Miley, H.S. (Pacific Northwest Laboratory, Battelle Blvd., Richland, WA 99352 (United States)); Arthur, R.J. (Pacific Northwest Laboratory, Battelle Blvd., Richland, WA 99352 (United States)); Avignone, F.T. (University of South Carolina, Columbia, SC 29208 (United States)); Barabash, A.S. (Institute for Theoretical and Experimental Physics, 117 259 Moscow (Russian Federation)); Brodzinski, R.L. (Pacific Northwest Laboratory, Battelle Blvd., Richland, WA 99352 (United States)); Collar, J.I. (University of South Carolina, Columbia, SC 29208 (United States)); Courant, H. (University of Minnesota, Minneapolis, MN 55455 (United States)); Garcia, E. (University of Zaragoza, Zaragoza (Spain)); Guerard, C.K. (University of South Carolina, Columbia, SC 29208 (United States)); Hensley, W.K. (Pacific Northwest Laboratory, Battelle Blvd., Richland, WA 99352 (United States)); Kirpichnikov, I.V. (Institute for Theoretical and Experimental Physics, 117 259 Moscow (Russian Federation)); Kl


    A Monte Carlo code has been developed to accurately simulate double-beta decay measurements. Coincident gamma rays, beta spectra, and angular correlations have been added to adequately simulate a complete [sup 100]Mo nuclear decay and provide corrections to experimentally determined detector efficiencies. This code has been used to strip certain low-background spectra obtained in the Homestake gold mine in Lead, SD, for the purpose of extremely sensitive materials assay for the construction of new, large, enriched germanium detectors. Assays as low as 9[mu]Bq/g of [sup 210]Pb in lead shielding were obtained. ((orig.))

  1. Simulated progress in double-beta decay (United States)

    Miley, H. S.; Arthur, R. J.; Avignone, F. T.; Barabash, A. S.; Brodzinski, R. L.; Collar, J. J.; Courant, H.; Garcia, E.; Guerard, C. K.; Hensley, W. K.; Kirpichnikov, I. V.; Klimenko, A. A.; Morales, A.; Morales, J.; Nunez-Lagos, R.; Osetrov, S. B.; Pogosov, V. S.; Puimedon, J.; Reeves, J. H.; Ruddick, K.; Saenz, C.; Salinas, A.; Sarsa, M. L.; Smolnikov, A. A.; Starostin, A. S.; Tamanyan, A. G.; Umatov, V. I.; Vasiliev, S. I.; Villar, J. A.


    A Monte Carlo code has been developed to accurately simulate double-beta decay measurements. Coincident gamma rays, beta spectra, and angular correlations have been added to adequately simulate a complete 100Mo nuclear decay and provide corrections to experimentally determined detector efficiencies. This code has been used to strip certain low-background spectra obtained in the Homestake gold mine in Lead, SD, for the purpose of extremely sensitive materials assay for the construction of new, large, enriched germanium detectors. Assays as low as 9 μBq/g of 210Pb in lead shielding were obtained.

  2. Atypical beta(s) haplotypes are generated by diverse genetic mechanisms. (United States)

    Zago, M A; Silva, W A; Dalle, B; Gualandro, S; Hutz, M H; Lapoumeroulie, C; Tavella, M H; Araujo, A G; Krieger, J E; Elion, J; Krishnamoorthy, R


    The majority of the chromosomes with the beta(S) gene have one of the five common haplotypes, designated as Benin, Bantu, Senegal, Cameroon, and Arab-Indian haplotypes. However, in every large series of sickle cell patients, 5-10% of the chromosomes have less common haplotypes, usually referred to as "atypical" haplotypes. In order to explore the genetic mechanisms that could generate these atypical haplotypes, we extended our analysis to other rarely studied polymorphic markers of the beta(S)-gene cluster, in a total of 40 chromosomes with uncommon haplotypes from Brazil and Cameroon. The following polymorphisms were examined: seven restriction site polymorphisms of the epsilongammadeltabeta-cluster, the pre-(G)gamma framework sequence including the 6-bp deletion/insertion pattern, HS-2 LCR (AT)xR(AT)y and pre-beta (AT)xTy repeat motifs, the GC/TT polymorphism at -1105-1106 of (G)gamma-globin gene, the C/T polymorphism at -551 of the beta-globin gene, and the intragenic beta-globin gene framework. Among the Brazilian subjects, the most common atypical structure (7/16) was a Bantu 3'-subhaplotype associated with different 5'-sequences, while in two chromosomes a Benin 3'-subhaplotype was associated with two different 5'-subhaplotypes. A hybrid Benin/Bantu configuration was also observed. In three chromosomes, the atypical haplotype differed from the typical one by the change of a single restriction site. In 2/134 chromosomes identified as having a typical Bantu RFLP-haplotype, a discrepant LCR repeat sequence was observed, probably owing to a crossover 5' to the epsilon-gene. Among 80 beta(S) chromosomes from Cameroon, 22 were associated with an atypical haplotype. The most common structure was represented by a Benin haplotype (from the LCR to the beta-gene) with a non-Benin segment 3' to the beta-globin gene. In two cases a Bantu LCR was associated with a Benin haplotype and a non-Benin segment 3' to the beta-globin gene. In three other cases, a more complex

  3. Therapeutic haemoglobin synthesis in beta-thalassaemic mice expressing lentivirus-encoded human beta-globin. (United States)

    May, C; Rivella, S; Callegari, J; Heller, G; Gaensler, K M; Luzzatto, L; Sadelain, M


    The stable introduction of a functional beta-globin gene in haematopoietic stem cells could be a powerful approach to treat beta-thalassaemia and sickle-cell disease. Genetic approaches aiming to increase normal beta-globin expression in the progeny of autologous haematopoietic stem cells might circumvent the limitations and risks of allogeneic cell transplants. However, low-level expression, position effects and transcriptional silencing hampered the effectiveness of viral transduction of the human beta-globin gene when it was linked to minimal regulatory sequences. Here we show that the use of recombinant lentiviruses enables efficient transfer and faithful integration of the human beta-globin gene together with large segments of its locus control region. In long-term recipients of unselected transduced bone marrow cells, tetramers of two murine alpha-globin and two human betaA-globin molecules account for up to 13% of total haemoglobin in mature red cells of normal mice. In beta-thalassaemic heterozygous mice higher percentages are obtained (17% to 24%), which are sufficient to ameliorate anaemia and red cell morphology. Such levels should be of therapeutic benefit in patients with severe defects in haemoglobin production.

  4. Nuclear Matrix Elements for the $\\beta\\beta$ Decay of the $^{76}$Ge

    CERN Document Server

    Brown, B A; Horoi, M


    The nuclear matrix elements for two-neutrino double-beta (2 n$\\beta\\beta$ ) and zero-neutrino double-beta (0 n$\\beta\\beta$) decay of 76 Ge are evaluated in terms of the configuration interaction (CI), quasiparticle random phase approximation (QRPA) and interacting boson model (IBM) methods. We show that the decomposition of the matrix elements in terms of interemediate states in 74 Ge is dominated by ground state of this nucleus. We consider corrections to the CI results that arise from configurations admixtures involving orbitals out-side of the CI configuration space by using results from QRPA, many-body-perturbation theory, and the connections to related observables. The CI two-neutrino matrix element is reduced due to the inclusion of spin-orbit partners, and to many-body correlations connected with Gamow-Teller beta decay. The CI zero-neutrino matrix element for the heavy neutrino is enhanced due to particle-particle correlations that are connected with the odd-even oscillations in the nuclear masse...

  5. Transforming growth factor-beta (TGF-beta) and programmed cell death in the vertebrate retina. (United States)

    Duenker, Nicole


    Programmed cell death (PCD) is a precisely regulated phenomenon essential for the homeostasis of multicellular organisms. Developmental systems, particularly the nervous system, have provided key observations supporting the physiological role of PCD. We have recently shown that transforming growth factor-beta (TGF-beta) plays an important role in mediating ontogenetic PCD in the nervous system. As part of the central nervous system the developing retina serves as an ideal model system for investigating apoptotic processes during neurogenesis in vivo as it is easily accessible experimentally and less complex due to its limited number of different neurons. This review summarizes data indicating a pivotal role of TGF-beta in mediating PCD in the vertebrate retina. The following topics are discussed: expression of TGF-beta isoforms and receptors in the vertebrate retina, the TGF-beta signaling pathway, functions and molecular mechanisms of PCD in the nervous system, TGF-beta-mediated retinal apoptosis in vitro and in vivo, and interactions of TGF-beta with other pro- and anti-apoptotic factors.

  6. Characterization of beta radiation fields using radiochromic films; Caracterizacao de campos de radiacao beta utilizando filmes radiocromicos

    Energy Technology Data Exchange (ETDEWEB)

    Benavente, Jhonny A.; Silva, Teogenes A. da, E-mail: jabc@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Programa de Pos-Graduacao em Ciencia e Tecnologia das Radiacoes, Minerais e Materiais; Meira-Belo, Luiz C.; Reynaldo, Sibele R. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)


    The objective of this work was to study the response of radiochromic films for beta radiation fields in terms of absorbed dose. The reliability of the EBT model Gafchromic radiochromic film was studied. A 9800 XL model Microtek, transmission scanner, a 369 model X-Rite optical densitometer and a Mini 1240 Shimadzu UV spectrophotometer were used for measurement comparisons. Calibration of the three systems was done with irradiated samples of radiochromic films with 0.1; 0.3; 0.5; 0.8; 1.0; 1.5; 2.0; 2.5; 3.0; 3.5; 4.5 e 5.0 Gy in beta radiation field from a Sr-90/Y-90 source. Calibration was performed by establishing a correlation between the absorbed dose values and the corresponding radiochromic responses. Results showed significant differences in the absorbed dose values obtained with the three methods. Absorbed dose values showed errors from 0.6 to 4.4%, 0.3 to 31.8% and 0.2 to 47.3% for the Microtek scanner, the X-Rite Densitometer and the Shimadzu spectrophotometer, respectively. Due to the easy acquisition and use for absorbed dose measurements, the densitometer and the spectrophotometer showed to be suitable techniques to evaluate radiation dose in relatively homogeneous fields. In the case of inhomogeneous fields or for a two dimension mapping of radiation fields to identify anisotropies, the scanner technique is the most recommended. (author)

  7. Macrocyclic beta-sheet peptides that mimic protein quaternary structure through intermolecular beta-sheet interactions. (United States)

    Khakshoor, Omid; Demeler, Borries; Nowick, James S


    This paper reports the design, synthesis, and characterization of a family of cyclic peptides that mimic protein quaternary structure through beta-sheet interactions. These peptides are 54-membered-ring macrocycles comprising an extended heptapeptide beta-strand, two Hao beta-strand mimics [JACS 2000, 122, 7654] joined by one additional alpha-amino acid, and two delta-linked ornithine beta-turn mimics [JACS 2003, 125, 876]. Peptide 3a, as the representative of these cyclic peptides, contains a heptapeptide sequence (TSFTYTS) adapted from the dimerization interface of protein NuG2 [PDB ID: 1mio]. 1H NMR studies of aqueous solutions of peptide 3a show a partially folded monomer in slow exchange with a strongly folded oligomer. NOE studies clearly show that the peptide self-associates through edge-to-edge beta-sheet dimerization. Pulsed-field gradient (PFG) NMR diffusion coefficient measurements and analytical ultracentrifugation (AUC) studies establish that the oligomer is a tetramer. Collectively, these experiments suggest a model in which cyclic peptide 3a oligomerizes to form a dimer of beta-sheet dimers. In this tetrameric beta-sheet sandwich, the macrocyclic peptide 3a is folded to form a beta-sheet, the beta-sheet is dimerized through edge-to-edge interactions, and this dimer is further dimerized through hydrophobic face-to-face interactions involving the Phe and Tyr groups. Further studies of peptides 3b-3n, which are homologues of peptide 3a with 1-6 variations in the heptapeptide sequence, elucidate the importance of the heptapeptide sequence in the folding and oligomerization of this family of cyclic peptides. Studies of peptides 3b-3g show that aromatic residues across from Hao improve folding of the peptide, while studies of peptides 3h-3n indicate that hydrophobic residues at positions R3 and R5 of the heptapeptide sequence are important in oligomerization.

  8. Improved estimate of the cross section for inverse beta decay

    CERN Document Server

    Ankowski, Artur M


    The hypothesis of the conserved vector current, relating the vector weak and isovector electromagnetic currents, plays a fundamental role in quantitative description of neutrino interactions. Despite being experimentally confirmed with great precision, it is not fully implemented in existing calculations of the cross section for inverse beta decay, the dominant mechanism of antineutrino scattering at energies below a few tens of MeV. In this article, I estimate the corresponding cross section and its uncertainty, ensuring conservation of the vector current. While converging to previous calculations at energies of several MeV, the obtained result is appreciably lower and predicts more directional positron production near the reaction threshold. These findings suggest that in the current estimate of the flux of geologically produced antineutrinos the 232Th and 238U components may be underestimated by 6.1 and 3.7%, respectively. The proposed search for light sterile neutrinos using a 144Ce--144Pr source is predi...

  9. beta-Scission of C-3 (beta-carbon) alkoxyl radicals on peptides and proteins

    DEFF Research Database (Denmark)

    Headlam, H A; Mortimer, A; Easton, C J


    of new reactive groups, including hydroperoxides. These processes can result in the loss of structural or enzymatic activity. Backbone fragmentation is known to occur via a number of mechanisms, most of which involve hydrogen abstraction from the alpha-carbon site on the backbone. In this study, we...... demonstrate that initial attack at a side chain site, the beta-position (C-3), can give rise to formation of alpha-carbon radicals, and hence backbone cleavage, via the formation and subsequent beta-scission of C-3 alkoxyl radicals. This beta-scission reaction is rapid (k estimated to be >10(7) s(-)(1)) even...

  10. Spectroscopy with {beta}2p and {beta}-{nu} recoil shifts

    Energy Technology Data Exchange (ETDEWEB)

    Fynbo, H.O.U. E-mail:; Axelsson, L.; Aeystoe, J.; Bergmann, U.C.; Borge, M.J.G.; Fraile, L.M.; Honkanen, A.; Hornshoej, P.; Jading, Y.; Jokinen, A.; Jonson, B.; Martel, I.; Mukha, I.; Nilsson, T.; Nyman, G.; Oinonen, M.; Riisager, K.; Siiskonen, T.; Smedberg, M.H.; Thaysen, J.; Tengblad, O.; Wenander, F


    The beta-delayed proton emission from the lightest Ar-isotopes has been measured with a high-granularity, large solid-angle Si-detector setup. Although designed for the detection of beta-delayed two-proton and three-proton events, the setup also permitted measurement of proton energy shifts due to the beta-neutrino recoil. We discuss how spectroscopic information can be extracted from such measurements, even at the drip line. For the case of {sup 31}Ar, the ground-state spin could be determined as 5/2.

  11. National pattern for the realization of the unit of the dose speed absorbed in air for beta radiation. (Method: Ionometer, cavity of Bragg-Gray implemented in an extrapolation chamber with electrodes of variable separation, exposed to a field of beta radiation of {sup 90}Sr/{sup 90}Y); Patron Nacional para la realizacion de la unidad de la rapidez de dosis absorbida en aire para radiacion beta. (Metodo: Ionometrico, cavidad de Bragg-Gray implementada en una camara de extrapolacion con electrodos de separacion variable, expuesta a un campo de radiacion beta de {sup 90}Sr/{sup 90}Y)

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez R, M. T.; Morales P, J. R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)


    From the year of 1987 the Department of Metrology of the ININ, in their Secondary Laboratory of Calibration Dosimetric, has a patron group of sources of radiation beta and an extrapolation chamber of electrodes of variable separation.Their objective is to carry out of the unit of the dose speed absorbed in air for radiation beta. It uses the ionometric method, cavity Bragg-Gray in the extrapolation chamber with which it counts. The services that offers are: i) it Calibration : Radioactive Fuentes of radiation beta, isotopes: {sup 90}Sr/{sup 90}Y; Ophthalmic applicators {sup 9}0{sup S}r/{sup 90}Y; Instruments for detection of beta radiation with to the radiological protection: Ionization chambers, Geiger-Muller, etc.; Personal Dosemeters. ii) Irradiation with beta radiation of materials to the investigation. (Author)

  12. Cell therapies for pancreatic beta-cell replenishment. (United States)

    Okere, Bernard; Lucaccioni, Laura; Dominici, Massimo; Iughetti, Lorenzo


    The current treatment approach for type 1 diabetes is based on daily insulin injections, combined with blood glucose monitoring. However, administration of exogenous insulin fails to mimic the physiological activity of the islet, therefore diabetes often progresses with the development of serious complications such as kidney failure, retinopathy and vascular disease. Whole pancreas transplantation is associated with risks of major invasive surgery along with side effects of immunosuppressive therapy to avoid organ rejection. Replacement of pancreatic beta-cells would represent an ideal treatment that could overcome the above mentioned therapeutic hurdles. In this context, transplantation of islets of Langerhans is considered a less invasive procedure although long-term outcomes showed that only 10 % of the patients remained insulin independent five years after the transplant. Moreover, due to shortage of organs and the inability of islet to be expanded ex vivo, this therapy can be offered to a very limited number of patients. Over the past decade, cellular therapies have emerged as the new frontier of treatment of several diseases. Furthermore the advent of stem cells as renewable source of cell-substitutes to replenish the beta cell population, has blurred the hype on islet transplantation. Breakthrough cellular approaches aim to generate stem-cell-derived insulin producing cells, which could make diabetes cellular therapy available to millions. However, to date, stem cell therapy for diabetes is still in its early experimental stages. This review describes the most reliable sources of stem cells that have been developed to produce insulin and their most relevant experimental applications for the cure of diabetes.

  13. Latin American food sources of carotenoids. (United States)

    Rodriguez-Amaya, D B


    Latin America has a wide variety of carotenogenic foods, notable for the diversity and high levels of carotenoids. A part of this natural wealth has been analyzed. Carrot, red palm oil and some cultivars of squash and pumpkin are sources of both beta-carotene and alpha-carotene. beta-carotene is the principal carotenoid of the palm fruits burití, tucumã and bocaiuva, other fruits such as loquat, marolo and West Indian cherry, and sweet potato. Buriti also has high amounts of alpha-carotene and gamma-carotene. beta-Cryptoxanthin is the major carotenoid in caja, nectarine, orange-fleshed papaya, orange, peach, tangerine and the tree tomato. Lycopene predominates in tomato, red-fleshed papaya, guava, pitanga and watermelon. Pitanga also has substantial amounts of beta-cryptoxanthin, gamma-carotene and rubixanthin. Zeaxanthin, principal carotenoid of corn, is also predominant only in piquí. delta-Carotene is the main carotenoid of the peach palm and zeta-carotene of passion fruit. Lutein and beta-carotene, in high concentrations, are encountered in the numerous leafy vegetables of the region, as well as in other green vegetables and in some varieties of squash and pumpkin. Violaxanthin is the principal carotenoid of mango and mamey and is also found in appreciable amounts in green vegetables. Quantitative, in some cases also qualitative, differences exist among cultivars of the same food. Generally, carotenoids are in greater concentrations in the peel than in the pulp, increase considerably during ripening and are in higher levels in foods produced in hot places. Other Latin America indigenous carotenogenic foods must be investigated before they are supplanted by introduced crops, which are often poorer sources of carotenoids.

  14. Strain-dependent differences in sensitivity of rat beta-cells to interleukin 1 beta in vitro and in vivo

    DEFF Research Database (Denmark)

    Reimers, J I; Andersen, H U; Mauricio, D


    The aim of this study was to investigate whether strain-dependent differences in beta-cell sensitivity to interleukin (IL) 1 beta exist in vitro and in vivo and if so, whether these differences correlate to variations in IL-1 beta-induced islet inducible nitric oxide synthase (iNOS) mRNA expression....../kg) or vehicle for 5 days. All the strains investigated were susceptible to IL-1 beta-induced changes in body weight, food intake, temperature, and plasma glucagon and corticosterone. However, IL-1 beta induced hyperglycemia and impairment of beta-cell glucose responsiveness in WK/Mol and LS/Mol rats...

  15. Latest results of NEXT-DEMO, the prototype of the NEXT 100 double beta decay experiment

    CERN Document Server

    Serra, L; Martin-Albo, J; Sorel, M; Gomez-Cadenas, J J


    NEXT-DEMO is a 1:4.5 scale prototype of the NEXT100 detector, a high-pressure xenon gas TPC that will search for the neutrinoless double beta decay of $^{136}$Xe. X-ray energy depositions produced by the de-excitation of Xenon atoms after the interaction of gamma rays from radioactive sources have been used to characterize the response of the detector obtaining the spatial calibration needed for close-to-optimal energy resolution. Our result, 5.5% FWHM at 30 keV, extrapolates to 0.6% FWHM at the Q value of $^{136}$Xe. Additionally, alpha decays from radon have been used to measure several detection properties and parameters of xenon gas such as electron-ion recombination, electron drift velocity, diffusion and primary scintillation light yield. Alpha spectroscopy is also used to quantify the activity of radon inside the detector, a potential source of background for most double beta decay experiments.

  16. Optimized Two-Baseline Beta-Beam Experiment

    CERN Document Server

    Choubey, Sandhya; Donini, Andrea; Fernandez-Martinez, Enrique


    We propose a realistic Beta-Beam experiment with four source ions and two baselines for the best possible sensitivity to theta_{13}, CP violation and mass hierarchy. Neutrinos from 18Ne and 6He with Lorentz boost gamma=350 are detected in a 500 kton water Cerenkov detector at a distance L=650 km (first oscillation peak) from the source. Neutrinos from 8B and 8Li are detected in a 50 kton magnetized iron detector at a distance L=7000 km (magic baseline) from the source. Since the decay ring requires a tilt angle of 34.5 degrees to send the beam to the magic baseline, the far end of the ring has a maximum depth of d=2132 m for magnetic field strength of 8.3 T, if one demands that the fraction of ions that decay along the straight sections of the racetrack geometry decay ring (called livetime) is 0.3. We alleviate this problem by proposing to trade reduction of the livetime of the decay ring with the increase in the boost factor of the ions, such that the number of events at the detector remains almost the same....

  17. Hereditary and sporadic beta-amyloidoses. (United States)

    Di Fede, Giuseppe; Giaccone, Giorgio; Tagliavini, Fabrizio


    Cerebral amyloidoses are chronic, progressive neurodegenerative diseases that are caused by the aggregation and deposition of misfolded proteins in the central nervous system, and lead to cognitive deficits, stroke, and focal neurological dysfunction including cerebellar and extrapyramidal signs. Among them, beta-amyloidoses are a heterogenous set of conditions characterised by the deposition of beta-amyloid protein in brain parenchyma and/or vessel walls that lead to the development of two main clinico-pathological entities: Alzheimer's disease and cerebral amyloid angiopathy, which may be sporadic or familial, and may also co-exist in the same patient. The aim of this review is to describe the most important differences in the pathways leading to parenchymal and cerebrovascular beta-amyloidoses, and the main clinical, neuropathological and biochemical characteristics of the two conditions. It also discusses the phenotypes associated with a series of familial and sporadic beta-amyloidoses in more detail in order to highlight the clinical and neuropathological features that may help to distinguish the different forms of disease.

  18. beta-decay of O-13

    NARCIS (Netherlands)

    Knudsen, HH; Fynbo, HOU; Borge, MJG; Boutami, R; Dendooven, P; Diget, CA; Eronen, T; Fox, S; Fraile, LM; Fulton, B; Huikary, J; Jeppesen, HB; Jokinen, AS; Jonson, B; Kankainen, A; Moore, [No Value; Nieminen, A; Nyman, G; Penttila, H; Riisager, K; Rinta-Antila, S; Tengblad, O; Wang, Y; Wilhelmsen, K; Aysto, J


    The beta decay of O-13 has been studied at the IGISOL facility of the Jyvaskyla accelerator centre (Finland). By developing a low-energy isotope-separated beam of O-13 and using a modern segmented charged-particle detector array an improved measurement of the delayed proton spectrum was possible. Pr

  19. Characterization of a Commercial Silicon Beta Cell

    Energy Technology Data Exchange (ETDEWEB)

    Foxe, Michael P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hayes, James C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mayer, Michael F. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McIntyre, Justin I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sivels, Ciara B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Suarez, Rey [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)


    Silicon detectors are of interest for the verification of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) due to their enhanced energy resolution compared to plastic scintillators beta cells. Previous work developing a figure-of-merit (FOM) for comparison of beta cells suggests that the minimum detectable activity (MDA) could be reduced by a factor of two to three with the use of silicon detectors. Silicon beta cells have been developed by CEA (France) and Lares Ltd. (Russia), with the PIPSBox developed by CEA being commercially available from Canberra for approximately $35k, but there is still uncertainty about the reproducibility of the capabilities in the field. PNNL is developing a high-resolution beta-gamma detector system in the shallow underground laboratory, which will utilize and characterize the operation of the PIPSBox detector. Throughout this report, we examine the capabilities of the PIPSBox as developed by CEA. The lessons learned through the testing and use of the PIPSBox will allow PNNL to strategically develop a silicon detector optimized to better suit the communities needs in the future.

  20. Association behavior of native beta-lactoglobulin

    DEFF Research Database (Denmark)

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


    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 variou...

  1. Poster: The EURISOL Beta-beam facility

    CERN Document Server

    The beta-beam concept for the generation of an electron (anti-)neutrino beam was proposed by Piero Zucchelli (CERN) in 2002. A first study of the possibility of using the existing CERN machines for the acceleration for radioactive ions to a relativistic gamma of roughly 100, for later storage in a new decay ring of approximately the size of SPS, was made in 2002. The results from this very first short study were very encouraging.In 2004 it was decided to incorporate a design study for the beta-beam within the EURISOL DS proposal. EURISOL is a project name for a next-generation radioactive beam facility based on the ISOL method for the production of intense radioactive beams for nuclear physics, astrophysics and other applications. The proposal was accepted with the beta-beam task as an integral part. The design study officially started 1 February 2005 and will run for 4 years resulting in a conceptual design report for a beta-beam facility.

  2. Graphene oxide strongly inhibits amyloid beta fibrillation

    NARCIS (Netherlands)

    Mahmoudi, Morteza; Akhavan, Omid; Ghavami, Mahdi; Rezaee, Farhad; Ghiasi, Seyyed Mohammad Amin


    Since amyloid beta fibrillation (AbF) plays an important role in the development of neurodegenerative diseases, we investigated the effect of graphene oxide (GO) and their protein-coated surfaces on the kinetics of Ab fibrillation in the aqueous solution. We showed that GO and their protein-covered

  3. Topical beta-Blockers and Mortality

    NARCIS (Netherlands)

    Muskens, Rogier P. H. M.; Wolfs, Roger C. W.; Wittenian, Jacqueline C. M.; Hofman, Albert; de Jong, Paulus T. V. M.; Stricker, Bruno H. C.; Jansonius, Nomdo M.


    Purpose: To study the associations between long-term and short-term use of topical beta-blockers and mortality. Design: Prospective population-based cohort study. Participants: To examine long-term effects, 3842 participants aged 55 years and older were recruited. To examine short-term effects, 484

  4. Tests of fundamental symmetries with beta decay

    NARCIS (Netherlands)

    vanKlinken, J


    Since the fall of parity in electroweak interactions the discrete transformations of parity, charge conjugation and time reversal are under close scrutiny for any sign of deviation from maximality where symmetry breaking seems to be complete (like P violation in beta decay) and for any sign of symme

  5. Beta Bremsstrahlung dose in concrete shielding (United States)

    Manjunatha, H. C.; Chandrika, B. M.; Rudraswamy, B.; Sankarshan, B. M.


    In a nuclear reactor, beta nuclides are released during nuclear reactions. These betas interact with shielding concrete and produces external Bremsstrahlung (EB) radiation. To estimate Bremsstrahlung dose and shield efficiency in concrete, it is essential to know Bremsstrahlung distribution or spectra. The present work formulated a new method to evaluate the EB spectrum and hence Bremsstrahlung dose of beta nuclides (32P, 89Sr, 90Sr-90Y, 90Y, 91Y, 208Tl, 210Bi, 234Pa and 40K) in concrete. The Bremsstrahlung yield of these beta nuclides in concrete is also estimated. The Bremsstrahlung yield in concrete due to 90Sr-90Y is higher than those of other given nuclides. This estimated spectrum is accurate because it is based on more accurate modified atomic number (Zmod) and Seltzer's data, where an electron-electron interaction is also included. Presented data in concrete provide a quick and convenient reference for radiation protection. The present methodology can be used to calculate the Bremsstrahlung dose in nuclear shielding materials. It can be quickly employed to give a first pass dose estimate prior to a more detailed experimental study.

  6. Alpha and Beta at the B Factories

    Energy Technology Data Exchange (ETDEWEB)

    Finocchiaro, Giuseppe; /Frascati


    We review recent experimental results on time-dependent CP asymmetries in the B system from the BABAR and Belle experiments. Measurements of the {alpha} and {beta} angles of the Unitarity Triangle of the CKM matrix are discussed. These measurements constitute stringent tests of the Standard Model, and are also used to search for new physics.

  7. A multipurpose tunable source of monochromatic X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Chesta, M.A.; Plivelic, T.S.; Mainardi, R.T. E-mail:


    The emission of characteristic X-rays from any chemical element induced by beta particles of high energy (10{sup 5}-10{sup 6} eV) is much higher than photon excitation, with the possible exception of selective excitation. This work describes the properties of a variable energy X-ray generator that uses {sup 90}Sr as a source of beta particles and a multitarget array in a transparent source geometry. This compact device provides, through suitable selection of the target material, over 30 monoenergetic lines spread uniformly in the energy range of between 6 and 100 keV. The X-ray photon flux thus generated has an intensity of between 10{sup 2}-10{sup 3} s{sup -1} sr{sup -1} per MBq of the beta source activity. With this single beta source, the X-ray yield is higher as compared with generators using {sup 241}Am or other X- or gamma-ray sources with the same activity, and the line's intensity changes by less than a factor of three over the whole energy range.

  8. Solvent-dependent diastereoselectivities in reductions of beta-hydroxyketones by SmI2. (United States)

    Chopade, Pramod R; Davis, Todd A; Prasad, Edamana; Flowers, Robert A


    The reductions of a series of beta-hydroxyketones by SmI(2) were examined in THF, DME, and CH(3)CN using methanol as a proton source. Reductions in THF and DME typically lead to the syn diastereomer with DME providing higher diastereoselectivities. Reductions in CH(3)CN provided the anti diastereomer predominantly. This study reveals that solvation plays an important role in substrate reduction by SmI(2). [reaction: see text

  9. Search for $\\beta^+$EC and ECEC processes in $^{112}$Sn

    CERN Document Server

    Barabash, A S; Nachab, A; Konovalov, S I; Umatov, V


    Limits on $\\beta^+$EC (here EC denotes electron capture) and ECEC processes in $^{112}$Sn have been obtained using a 380 cm$^3$ HPGe detector and an external source consisting of 53.355 g enriched tin (94.32% of $^{112}$Sn). A limit with 90% C.L. on the $^{112}$Sn half-life of $4.7\\times 10^{20}$ y for the ECEC(0$\

  10. Dry-boxes for manipulation of high-energy {beta} emitters; Bottes pour manipulation d'emetteurs {beta} energiques

    Energy Technology Data Exchange (ETDEWEB)

    Boclet, K.; Laurent, H. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires


    Because of the thinners of latex or neoprene gloves and the high intensity of Bremsstrahlung radiation, manipulation of pure high-energy {beta}{sup -} emitters is impossible in ordinary dry-boxes. There are many types of box equipped with heavy lead or steel protection, but their use for radioelements such as {sup 32}P, {sup 90}Sr, {sup 90}Y is not justified. We have devised units known as 'tong boxes' which, while retaining much of the flexibility of operation found in dry-boxes, provide adequate protection. 1 curie of {sup 32}P placed in the centre of the enclosure gives about 15 mR/ 8 h. at the part of the wall closest to the source. (author) [French] La faible epaisseur des gants de latex ou de neoprene et l'importance du rayonnement de freinage rendent impossible la manipulation des emetteurs {beta}{sup -} purs energiques dans des boites a gants normales. Il existe de nombreux types d'enceintes dotees d'une forte protection de plomb ou d'acier dont l'emploi n'est pas justifie pour des radioelements tels que {sup 32}P, {sup 90}Sr, {sup 90}Y. Nous avons realise des ensembles appeles 'Boites a Pinces', qui tout en conservant une grande partie de la souplesse d'utilisation des boites a gants sont dotees d'une protection suffisante. 1 curie de {sup 32}P place au centre de l'enceinte donne environ 15 mR/ 8 h au contact de la paroi la plus rapprochee de la source. (auteur)

  11. Universality in Chiral Random Matrix Theory at $\\beta =1$ and $\\beta =4$

    CERN Document Server

    Sener, M K


    In this paper the kernel for spectral correlation functions of the invariant chiral random matrix ensembles with real ($\\beta =1$) and quaternion real ($\\beta = 4$) matrix elements is expressed in terms of the kernel of the corresponding complex Hermitean random matrix ensembles ($\\beta=2$). Such identities are exact in case of a Gaussian probability distribution and, under certain smoothness assumptions, they are shown to be valid asymptotically for an arbitrary finite polynomial potential. They are proved by means of a construction proposed by Brézin and Neuberger. Microscopic universality for all three chiral ensembles then follows from universal behavior for $\\beta =2$ both at the hard edge (shown by Akemann, Damgaard, Magnea and Nishigaki) and at the soft edge of the spectrum (shown by Kanzieper and Freilikher).


    Directory of Open Access Journals (Sweden)

    Ante Perković


    Full Text Available The capital asset pricing model (CAPM is one of the most important models in financial economics and it has a long history of theoretical and empirical investigations. The main underlying concept of the CAPM model is that assets with a high risk (high beta should earn a higher return than assets with a low risk (low beta and vice versa. The implication which can be drawn out of this is that all assets with a beta above zero bear some risk and therefore their expected return is above the return of the risk-free rate. In this research observation on monthly stock prices on Croatian stock market from January 1st 2005 until December 31st 2009 is used to form our sample. CROBEX index is used as proxy of the market portfolio. The results demonstrate that beta can not be trusted in making investment decisions and rejects the validity of the whole CAPM model on Croatian stock market.

  13. Conformation, molecular packing and field effect mobility of regioregular beta,beta'-dihexylsexithiophiophene

    DEFF Research Database (Denmark)

    Kiriy, N.; Kiriy, A.; Bocharova, V.


    by the pulse-radiolysis time-resolved microwave conductivity (PR-TRMC) technique was found to be Sigmamu(min) = 3.9 x 10(-3) cm(2) V-1 s(-1), which is comparable with the PR-TRMC mobility found for alpha,omega-DH6T. The field-effect mobility (FEM) of beta,beta'-DH6T was found to be on the order of 10(-5) cm(2......) V-1 s(-1), which is considerably less than the FEM of alpha,omega-DH6T. To understand the reason for such poor macroscopic electrical properties, the conformation and the molecular packing of beta,beta'-DH6T were systematically studied by means of UV-vis spectroscopy, scanning electron microscopy...

  14. Interleukin-1 beta (IL-1 beta) induces thrombocytosis in mice: Possible implication of IL-6

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, H.; Ishibashi, T.; Shikama, Y.; Okano, A.; Akiyama, Y.; Uchida, T.; Maruyama, Y. (Fukushima Medical College (Japan))


    We administered recombinant human interleukin-1 beta (IL-1 beta), the common mediator of inflammation process, to C57B1/6 male mice (0.5 microgram, every 12 hours over five times) intraperitoneally and consequently induced a remarkable thrombocytosis. Day 1 was designated as the following day of the last injection in the morning. A significant thrombocytosis was observed on days 1 through 5 with a peak on day 2 (162 +/- 9 x 10(4)/mm3) compared with the control mice injected with heated IL-1 beta (101 +/- 11 x 10(4)/mm3). A striking increase in mean size of marrow megakaryocytes was noted on days 1 and 2. The incorporation of 75Se-selenomethionine into circulating platelets as a measure of platelet production was about 2.3 times higher in IL-1 beta-treated mice than in control mice. To determine which factor(s) is responsible for elicited thrombocytosis, the in vitro studies and bioassays for several hematopoietic factors were performed. IL-1 beta by itself did not stimulate megakaryocytopoiesis in vitro, suggesting that the thrombocytosis is attributed to other factor(s) via IL-1 beta stimulation. Serum colony-stimulating factor (CSF) activity after a single IL-1 beta (0.5 microgram) injection, monitored by colony assay with 10% tested serum, peaked at 3 hours. Formed colonies were mostly granulocyte (G) and granulocyte-macrophage (GM)-types, and studies using rabbit anti-mouse GM-CSF serum or using human marrow as target cells showed that the CSF activity of the tested serum consisted of, at least, GM-CSF and G-CSF. Addition of IL-3 concomitantly with the tested serum gave rise to a greater number of megakaryocytic colonies. Serum IL-3, monitored by IL-3-dependent cell line 32D clone 5, and erythropoietin activities were not detected at serum level in IL-1 beta-treated mice.

  15. Construction of a {gamma}-{gamma} and {beta}-{gamma} coincidence measurement system for precise determination of nuclear data

    Energy Technology Data Exchange (ETDEWEB)

    Furutaka, Kazuyoshi; Nakamura, Shoji; Harada, Hideo; Katoh, Toshio [Japan Nuclear Cycle Development Institute, Tokai Works, Tokai, Ibaraki (Japan)


    A {gamma}-{gamma} and {beta}-{gamma} coincidence measurement system was constructed for the precise determination of nuclear data, such as thermal neutron capture cross sections and {gamma}-ray emission probabilities. The validity of the system was tested by a {gamma}-{gamma} coincidence measurement with a {sup 60}Co standard source. (author)

  16. [Measurement of C14 beta-radioactivity of stable natural origin taurine (2-aminoethanesulfonic acid) in bovine bile]. (United States)

    Gaetano, G; Bisegna, F; Bisio, V; Parenti, M


    Taurine from natural sources has gained great importance as essential nutrient in milk for formula-fed infants. There is a strong request for a method capable of determining the natural origin of taurine. The measure of beta-radioactivity of 14C of taurine by means of liquid scintillation counting proved the most reliable. A simple method is reported.

  17. Effects of flour and milling debris on efficacy of beta-cyfluthrin for control of Tribolium castaneum (United States)

    Laboratory and field studies were conducted to determine if accumulation of a flour food source or milling debris affected residual efficacy of beta-cyfluthrin for control of Tribolium castaneum (Herbst), the red flour beetle. In the laboratory study, the high label rate of 20 mg active ingredient (...

  18. Monte Carlo investigation of single cell beta dosimetry for intraperitoneal radionuclide therapy

    Energy Technology Data Exchange (ETDEWEB)

    Syme, A M [Department of Physics, University of Alberta, 412 Avadh Bhatia Physics Laboratory, Edmonton, Alberta, T6G 2J1 (Canada); Kirkby, C [Department of Physics, University of Alberta, 412 Avadh Bhatia Physics Laboratory, Edmonton, Alberta, T6G 2J1 (Canada); Riauka, T A [Department of Medical Physics, Cross Cancer Institute, University of Alberta, 11560 University Avenue, Edmonton, Alberta, T6G 1Z2 (Canada); Fallone, B G [Department of Physics, University of Alberta, 412 Avadh Bhatia Physics Laboratory, Edmonton, Alberta, T6G 2J1 (Canada); McQuarrie, S A [Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, 3118 Dentistry/Pharmacy Centre, Edmonton, Alberta, T6G 2N8 (Canada)


    Single event spectra for five beta-emitting radionuclides (Lu-177, Cu-67, Re-186, Re-188, Y-90) were calculated for single cells from two source geometries. The first was a surface-bound isotropically emitting point source and the second was a bath of free radioactivity in which the cell was submerged. Together these represent a targeted intraperitoneal radionuclide therapy. Monoenergetic single event spectra were calculated over an energy range of 11 keV to 2500 keV using the EGSnrc Monte Carlo system. Radionuclide single event spectra were constructed by weighting monoenergetic single event spectra according to radionuclide spectra appropriate for each source geometry. In the case of surface-bound radioactivity, these were radionuclide beta decay spectra. For the free radioactivity, a continuous slowing down approximation spectrum was used that was calculated based on the radionuclide decay spectra. The frequency mean specific energy per event increased as the energy of the beta emitter decreased. This is because, at these energies, the stopping power of the electrons decreases with increasing energy. The free radioactivity produced a higher frequency mean specific energy per event than the corresponding surface-bound value. This was primarily due to the longer mean path length through the target for this geometry. This information differentiates the radionuclides in terms of the physical process of energy deposition and could be of use in the radionuclide selection procedure for this type of therapy.

  19. Source rock


    Abubakr F. Makky; Mohamed I. El Sayed; Ahmed S. Abu El-Ata; Ibrahim M. Abd El-Gaied; Mohamed I. Abdel-Fattah; Zakaria M. Abd-Allah


    West Beni Suef Concession is located at the western part of Beni Suef Basin which is a relatively under-explored basin and lies about 150 km south of Cairo. The major goal of this study is to evaluate the source rock by using different techniques as Rock-Eval pyrolysis, Vitrinite reflectance (%Ro), and well log data of some Cretaceous sequences including Abu Roash (E, F and G members), Kharita and Betty formations. The BasinMod 1D program is used in this study to construct the burial history ...

  20. Effect of heating rate on temperature of titanium alloy (. cap alpha. +. beta. ). -->. beta. transformaton

    Energy Technology Data Exchange (ETDEWEB)

    Gridnev, V.N.; Ivasishin, O.M.; Markovskij, P.E. (AN Ukrainskoj SSR, Kiev. Inst. Metallofiziki)


    The effect of doping of two-phase titaniums alloys and morphology of initial structure on the Tsub(t) temperature shift value of (..cap alpha..+..beta..)..--> beta.. transformation depending on heating rate is investigated. It has been found that the Tsub(t) shift occurs in the strictly determined temperature range depending on chemical alloy composition. The Tsub(t) shift is directly proportional to the Ksub(..beta..) coefficient applied as a quantitative alloying characteristic as well as a dimensional factor equal either to the plate thickness or the ..cap alpha..-phase globule diameter depending on the type of initial structure. In the limits of this temperature range the (..cap alpha..+..beta..)..--> beta..-transformation occurs completely according to the diffusion mechanism. The critical heating rate at which maximum permissible Tsub(t) value is attained and above which its stabilization is observed is determined by the same parameters - the alloy doping degree characterized by the Ksub(..beta..) coefficient and the ..cap alpha..-phase crystal dimensions in the initial structure.

  1. TGF-beta and BMP in breast cancer cell invasion

    NARCIS (Netherlands)

    Naber, Hildegonda Petronella Henriëtte


    TGF-beta and BMPs are members of the TGF-beta superfamily of cytokines which play an important role in a multitude of processes. In cancer, TGF-beta is known for its dual role: in early stages it inhibits cancer cell proliferation, whereas in later stages it promotes invasion and metastasis. In this

  2. First forbidden beta decay of some strongly deformed nuclei

    NARCIS (Netherlands)

    Werf, Siebren Ysbrand van der


    In this thesis we present measurements of the shape factors of the first forbidden beta decays of the nuclei Tm^170, Re^186, Re^188 and Lu^176m. For Lu^176m, also the beta gamma directionalcorrelation was measured. In chapter I formulas for the observable quantities in first forbidden beta decay and

  3. Partial beta-amylolysis retards starch retrogradation in rice products. (United States)

    Yao, Yuan; Zhang, Jingmin; Ding, Xiaolin


    Starch retrogradation is the main cause of quality deterioration of starch-containing foods during storage. The current work investigated the effect of partial beta-amylolysis on the retrogradation of rice starch and the potential of beta-amylase in preparing rice products with extended shelf life. Isolated amylopectin, whole rice starch, and rice flour from a regular rice cultivar were partially hydrolyzed by either reagent-grade or food-grade beta-amylase. The degree of beta-amylolysis was expressed as average external chain length () for isolated amylopectin or the degree of hydrolysis (%) for other starch systems. Pulsed nuclear magnetic resonance was used to monitor starch retrogradation during storage at 4 degrees C. The results indicated that partial beta-amylolysis using reagent-grade beta-amylase retarded amylopectin retrogradation by shortening the of amylopectin. When was below DP 11.6, the amylopectin retrogradation was essentially inhibited. Partial beta-amylolysis had a similar effect on the amylopectin retrogradation in the whole starch system. The maltose produced in beta-amylolysis might slightly attenuate the retrogradation-retarding effect of partial beta-amylolysis. The effect of food-grade beta-amylase on starch retrogradation was also evident, although less effective than that of reagent-grade beta-amylase. The retrogradation-retarding effect of food-grade beta-amylase was also demonstrated in rice flour system, indicating a potential method for controlling the starch retrogradation of rice products.

  4. Estimating security betas using prior information based on firm fundamentals

    NARCIS (Netherlands)

    Cosemans, Mathijs; Frehen, Rik; Schotman, Peter; Bauer, Rob


    We propose a hybrid approach for estimating beta that shrinks rolling window estimates towards firm-specific priors motivated by economic theory. Our method yields superior forecasts of beta that have important practical implications. First, hybrid betas carry a significant price of risk in the cros

  5. Mechanisms of beta-amyloid neurotoxicity : Perspectives of pharmacotherapy

    NARCIS (Netherlands)

    Harkany, T; Abraham, [No Value; Konya, C; Nyakas, C; Zarandi, M; Penke, B; Luiten, PGM


    One of the characteristic neuropathological hallmarks of Alzheimer's disease (AD) is the extracellular accumulation of beta -amyloid peptides (A beta) in neuritic plaques, Experimental data indicate that different molecular forms of A beta affect a wide array of neuronal and glial functions and ther

  6. Comparative seric TGF({beta}1, {beta}2) levels and platelets count response in total body irradiated baboons; Evolution comparee des taux seriques des TGF ({beta}1, {beta}2) et de la numeration plaquettaire chez le babouin irradie globalement

    Energy Technology Data Exchange (ETDEWEB)

    Mestries, J.C.; Veyret, J.; Agay, D.; Van Uye, A.; Caterini, R.; Herodin, F.; Mathieu, J.; Chancerelle, Y.


    Total body irradiation associated or not with r-hIL-6 treatment a relation between TGF-{beta}1 and TGF-{beta}2 blood levels and platelets count. During radio-induced thrombocytopenia, by decreasing its ability to inhibit proliferation of stem cells and megakaryocytopoiesis, the TGF-{beta} falling induced a favorable condition for hematopoietic recovery. (author). 5 refs.

  7. Induction of beta-lactamase production in Pseudomonas aeruginosa biofilm

    DEFF Research Database (Denmark)

    Giwercman, B; Jensen, E T; Høiby, N;


    Imipenem induced high levels of beta-lactamase production in Pseudomonas aeruginosa biofilms. Piperacillin also induced beta-lactamase production in these biofilms but to a lesser degree. The combination of beta-lactamase production with other protective properties of the biofilm mode of growth...

  8. Isolation and characterization of chicken and turkey beta 2-microglobulin

    DEFF Research Database (Denmark)

    Skjødt, K; Welinder, K G; Crone, M


    Chicken and turkey beta 2-m were isolated from citrated plasma in sequential use of three chromatographic steps: affinity chromatography, gel filtration chromatography and anion-exchange chromatography. The purified protein was identified as beta 2-m by reaction with a beta 2-m specific monoclonal...

  9. Stereoselective synthesis of nicotinamide beta-riboside and nucleoside analogs. (United States)

    Franchetti, Palmarisa; Pasqualini, Michela; Petrelli, Riccardo; Ricciutelli, Massimo; Vita, Patrizia; Cappellacci, Loredana


    The beta-anomers of N-ribofuranosylnicotine-3-carboxamide (beta-NAR) and its nicotinic acid analog (beta-NaR) were obtained by stereoselective synthesis via glycosylation of the presilylated bases under Vorbruggen's protocol. A NAR analog, methylated in position 3 of the ribosylic moiety, is also reported.

  10. Right tail expansion of Tracy-Widom beta laws

    CERN Document Server

    Borot, Gaëtan


    Using loop equations, we compute the large deviation function of the maximum eigenvalue to the right of the spectrum in the Gaussian beta matrix ensembles, to all orders in 1/N. We then give a physical derivation of the all order asymptotic expansion of the right tail Tracy-Widom beta laws, for all positive beta, by studying the double scaling limit.

  11. Studies of {beta}-delayed proton decays of N{approx_equal}Z nuclei around {sup 100}Sn at the GSI-ISOL facility

    Energy Technology Data Exchange (ETDEWEB)

    Mukha, I. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); Batist, L. [St. Petersburg Nuclear Physics Institute, Gatchina (Russian Federation); Universita ' Federico II' and INFN Napoli, Naples (Italy); Becker, F. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); Blazhev, A. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); University of Sofia, Sofia (Bulgaria); Bruechle, A. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); Doering, J. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); Gorska, M. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); Grawe, H. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); Faestermann, T. [Technical University, Munich (Germany); Hoffman, C. [Florida State University, Tallahassee, FL (United States); Janas, Z. [Warsaw University, Warsaw (Poland); Jungclaus, A. [Universidad Autonoma de Madrid (Spain); Karny, M. [Warsaw University, Warsaw (Poland); Kavatsyuk, M. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); National T. Shevchenko University, Kiev (Ukraine); Kavatsyuk, O. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); Kirchner, R. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); La Commara, M. [Universita ' Federico II' and INFN Napoli, Naples (Italy); Mazzocchi, C. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); Plettner, C. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); Plochocki, A. [Warsaw University, Warsaw (Poland); Roeckl, E. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); Romoli, M. [Universita ' Federico II' and INFN Napoli, Naples (Italy); Schaedel, M. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); Schwengner, R. [Inst. fuer Kern und Hadronenphysik, Forschungzentrum Rossendorf, Dresden (Germany)] [and others


    Beta decays of {sup 94,96}Ag and {sup 103}Sn nuclei into proton channels have been studied in the recent experiments at the GSI-ISOL facility. New efficient and chemically selective ion sources provided the highest yields of light silver and tin isotopes. Large arrays of germanium {gamma}-ray and silicon charged-particle detectors, as well as a total absorption spectrometer (TAS) were used to measure {beta}-proton, proton-{gamma}, {beta}-proton-{gamma} and proton-{gamma}-{gamma} spectra. For the decay of {sup 94}Ag, we observed high-spin states in {sup 93}Rh populated by proton emission following {beta} decay, whose largest spin value ({>=}39/2) yields an experimental proof for the existence of a second high-spin isomer in {sup 94}Ag with I{>=}17. Its {beta}-decay energy is at least 16.8 MeV, corresponding to an excitation energy {>=}5.5 MeV. For {sup 103}Sn, the {gamma} rays measured in coincidence with {beta}-delayed protons allowed us to establish the {beta}-decay properties of this isotope. In particular, a Q{sup EC} value of 7.5(6) MeV is derived from the intensity ratio of protons that are preceded either by EC or by {beta}{sup +} decays and populate the 2{sup +} state in {sup 102}Cd.

  12. Involvement of the serine/threonine p70S6 kinase in TGF-beta1-induced ADAM12 expression in cultured human hepatic stellate cells

    DEFF Research Database (Denmark)

    Le Pabic, Hélène; L'Helgoualc'h, Annie; Coutant, Alexandre;


    In chronic liver injury, quiescent hepatic stellate cells change into proliferative myofibroblast-like cells, which are a main source of fibrosis. We have recently reported that these cells synthesize ADAM12, a disintegrin and metalloprotease whose expression is up-regulated by TGF-beta1 in liver...... cancers. Here, we studied the role of the serine/threonine p70S6 kinase (p70S6K) in regulating TGF-beta1-induced ADAM12 expression....

  13. Meiotic recombination in the beta globin gene cluster causing an error in prenatal diagnosis of beta thalassaemia.


    Camaschella, C.; Serra, A.; Saglio, G; Bertero, M T; Mazza, U; Terzoli, S; Brambati, B; Cremonesi, L.; Travi, M; Ferrari, M


    In the course of a prenatal diagnosis for beta thalassaemia by linkage analysis of restriction fragment length polymorphisms, a homozygous beta thalassaemia fetus was misdiagnosed as beta thalassaemia trait. Extensive studies of the polymorphic sites within the beta globin gene cluster in all the members of the family resulted in the conclusion that the paternal chromosome 11 of the newborn was different from that expected. Paternity was confirmed by HLA typing and blood group studies. The an...

  14. The role of enhanced cutaneous IL-1beta signaling in a rat tibia fracture model of complex regional pain syndrome. (United States)

    Li, Wen-Wu; Sabsovich, Ilya; Guo, Tian-Zhi; Zhao, Rong; Kingery, Wade S; Clark, J David


    Tibia fracture in rats initiates a syndrome resembling the complex regional pain syndrome type I. Accumulating evidence indicates that IL-1beta is involved in the modulation of nociceptive information and it acts as an intermediate inflammatory mediator via up-regulation of NGF. We hypothesized that IL-1beta signaling might mediate the development of the CRPS-like changes after tibial fracture, either directly or by stimulating NGF expression. Rats underwent distal tibia fracture and casting for 4 weeks and were chronically treated with an IL-1 receptor antagonist (IL-1ra). Nociceptive testing and assessment of edema and hindpaw warmth were performed at baseline and after cast removal. Bone microarchitecture was evaluated by micro-computed tomography. Confocal immunofluorescence and in situ hybridization techniques were used to evaluate changes in the cutaneous expression of IL-1beta at 4 weeks post-fracture. The nociceptive and vascular effects of intraplantar IL-1beta injections were evaluated in intact rats at different time points after injection. We found that: (1) IL-1ra reduced fracture-induced nociceptive sensitization, but did not decrease hindpaw edema or warmth, (2) fracture chronically up-regulated IL-1beta mRNA and protein expression in hindpaw skin keratinocytes, (3) IL-1beta intraplantar injection induced mechanical allodynia in a dose-dependent manner and stimulated keratinocyte NGF expression in the hindpaw skin, and (4) intraplantar injection of NGF-induced nociceptive sensitization. Collectively, these results indicate that cutaneous IL-1beta signaling can contribute to chronic regional nociceptive sensitization after fracture, possibly by stimulating NGF over-expression in keratinocytes. Our data also highlight the importance of the keratinocyte as the primary source of post-traumatic IL-1beta over-expression.

  15. Distinct down-regulation of cardiac beta 1- and beta 2-adrenoceptors in different human heart diseases. (United States)

    Steinfath, M; Geertz, B; Schmitz, W; Scholz, H; Haverich, A; Breil, I; Hanrath, P; Reupcke, C; Sigmund, M; Lo, H B


    Cardiac beta-adrenoceptor density and beta 1- and beta 2-subtype distribution were examined in human left ventricular myocardium from transplant donors serving as controls and from patients with mitral valve stenosis, aortic valve stenosis, idiopathic dilated cardiomyopathy, and ischaemic cardiomyopathy respectively. The total beta-adrenoceptor density was similar in transplant donors and patients with moderate heart failure (NYHA II-III) due to mitral valve stenosis, but was markedly reduced in all forms of severe heart failure (NYHA III-IV) studied. A reduction of both beta 1- and beta 2-adrenoceptors was found in patients with severe heart failure due to mitral valve stenosis or ischaemic cardiomyopathy. In contrast, a selective down-regulation of beta 1-adrenoceptors with unchanged beta 2-adrenoceptors and hence a relative increase in the latter was observed in idiopathic dilated cardiomyopathy and aortic valve stenosis. It is concluded that the extent of total beta-adrenoceptor down-regulation is related to the degree of heart failure. Selective loss of beta 1-adrenoceptors is not specific for idiopathic dilated cardiomyopathy but also occurs in aortic valve stenosis. Changes in beta 1- and beta 2-subtype distribution are rather related to the aetiology than to the clinical degree of heart failure.

  16. Rheumatoid factors from patients with rheumatoid arthritis react with Des-Lys58-beta 2m, modified beta 2-microglobulin

    DEFF Research Database (Denmark)

    Williams, R C; Nissen, Mogens Holst; Malone, C C


    Ten polyclonal IgM rheumatoid factor (RF) preparations, affinity-purified from IgG columns, from patients with rheumatoid arthritis were studied for their ELISA reactivity with native beta 2m in parallel with Lys58-cleaved beta 2m and Des-Lys58-beta 2m, the latter representing cleavage products...

  17. Effect of environmental estrogens on IL-1beta promoter activity in a macrophage cell line. (United States)

    Ruh, M F; Bi, Y; Cox, L; Berk, D; Howlett, A C; Bellone, C J


    Environmental estrogens or estrogen disrupters have recently received a great deal of attention because of their potential health impact on reproductive tissues. Few, if any, studies have been made on the impact of these compounds on the immune system. We sought to determine the activities of various environmental estrogens on the modulation of the interleukin-1beta (IL-1beta) gene in a model monocytic cell line, hER + IL-1beta-CAT+. This cell line stably transfected with the human estrogen receptor, and an IL-1beta promoter construct fused to the CAT reporter gene allows us to monitor the effect of estrogenic compounds on IL-1beta promoter activity. 17beta-estradiol (E2) markedly enhanced lipopolysaccharide- (LPS) induced IL-1beta promoter-driven CAT activity in a dose-dependent manner. The mycotoxins alpha-zearalenol and zearalenone both exhibited full agonist activity, but at lower potencies, with EC50 values of 1.8 and 54 nM, respectively, compared with E2 at 0.5 nM. In addition, genistein was a very low-potency agonist, having an EC50 of 1.5 microM. Similar to the E2 response, the slope factors for alpha-zearalenol, zearalenone, and genistein were close to 3.0, suggesting positive cooperativity in the estrogenic response. The activity of the mycotoxins appeared to be mediated through the estrogen receptor, since both the antiestrogens H1285 and ICI 182,780 effectively inhibited their agonist activity in a dose-dependent manner. Representative environmental estrogenic compounds both from plant and industrial sources were also tested. Unlike the mycoestrogens, none of the compounds, with the exception of genistein, synergized with LPS to enhance IL-1beta promoter activity. When tested for antiestrogenic activity, the industrial compound 4-octylphenol was able to antagonize the response to E2; however, the response was three orders of magnitude less potent than H 1285. Naringenin, a plant flavonoid, showed little or no ability to antagonize the response to E2

  18. Amylase,. beta. -glucanase and protease activities from a mutant of Bacillus subtilis

    Energy Technology Data Exchange (ETDEWEB)

    Yin, X.S.; Li, Y.X. (Wuxi Inst. of Light Industry, JS (China). Dept. of Fermentation Technology); Stark, J.R. (International Centre for Brewing and Distilling, Edinburgh (UK))


    Enzymes in the shake culture of a mutant of Bacillus subtilis developed mainly during the stationary phase of growth. Extracellular {alpha}-amylase and protease activities increased and then declined to relatively low levels after 48 h of incubation while the {beta}-glucanase activity remained high. The production of extracellular proteolytic activity commenced only when the low molecular weight nitrogen source in the medium was completely consumed. Enzymes were fractionated by ion-exchange chromatography and the molecular weights of {beta}-glucanase, {alpha}-amylase, protease I and protease II were estimated by gel filtration to be 1.3x10{sup 4}, 3.2x10{sup 4}, 6.3x10{sup 3} and 2.0x10{sup 4}, respectively. The {beta}-glucanase and {alpha}-amylase showed maximum activities at around pH 7, but the two proteases had different pH optima (pH 6-7 and 8.5, respectivelty). The presence of proteolytic activity in the enzyme preparation had a significant effect on the stability of the {beta}-glucanase and the {alpha}-amylase at 65deg C. (orig.).

  19. A fitness cost associated with the antibiotic resistance enzyme SME-1 beta-lactamase. (United States)

    Marciano, David C; Karkouti, Omid Y; Palzkill, Timothy


    The bla(TEM-1) beta-lactamase gene has become widespread due to the selective pressure of beta-lactam use and its stable maintenance on transferable DNA elements. In contrast, bla(SME-1) is rarely isolated and is confined to the chromosome of carbapenem-resistant Serratia marcescens strains. Dissemination of bla(SME-1) via transfer to a mobile DNA element could hinder the use of carbapenems. In this study, bla(SME-1) was determined to impart a fitness cost upon Escherichia coli in multiple genetic contexts and assays. Genetic screens and designed SME-1 mutants were utilized to identify the source of this fitness cost. These experiments established that the SME-1 protein was required for the fitness cost but also that the enzyme activity of SME-1 was not associated with the fitness cost. The genetic screens suggested that the SME-1 signal sequence was involved in the fitness cost. Consistent with these findings, exchange of the SME-1 signal sequence for the TEM-1 signal sequence alleviated the fitness cost while replacing the TEM-1 signal sequence with the SME-1 signal sequence imparted a fitness cost to TEM-1 beta-lactamase. Taken together, these results suggest that fitness costs associated with some beta-lactamases may limit their dissemination.

  20. First observation of a reactor-status effect on the beta+ decay rate of 22Na

    CERN Document Server

    de Meijer, Robert; Stegenga, Jan; Steyn, Steph; Lindsay, Robbie; van Rooy, Milton


    In the search for an electron antineutrino detection method with sensitivity below the 1.8 MeV threshold for the inverse beta decay reaction, beta-decay counting experiments with ca. 3 kBq 22Na and 60Co sources were conducted at unit #1 (2.775 GWth) of the Koeberg Nuclear Power Station in South Africa. The goal was to determine if the rate of decay is measurably influenced by a change between the ON-OFF status of such a reactor. The experimental setup consisted of a single NaI crystal to measure de-excitation and annihilation photons associated with beta-decay. Its volume and well shape were purposely chosen to use coincidence summing in the interval 170-2452 keV to differentiate between electron capture and beta+ emission in 22Na. The Pb-shielded setup was placed in the seismic vault underneath the containment building, thereby shielded from the reactor core by 8 m of uninterrupted concrete. For 22Na two measurement series were made, each covering an ON-OFF-ON cycle of the reactor. The following fractional c...

  1. Characterization and regulation of. beta. /sub 2/-adrenergic receptors in rat vas deferens

    Energy Technology Data Exchange (ETDEWEB)

    May, J.M.


    ..beta../sub 2/-Adrenergic receptors in rat vas deferens were examined by measuring the binding of /sup 125/I-pindolol (/sup 125/IPIN) to membrane preparations and the inhibition of evoked contractions in intact tissues. /sup 125/IPIN labeled a single class of binding sites with mass action kinetics. Affinity constants for ..beta..-adrenergic receptor antagonists calculated from both binding and functional experiments agreed well, suggesting that /sup 125/IPIN labels the functional ..beta../sub 2/-adrenergic receptor. n-Bromoacetylalprenololmenthane (BAAM) was used to decrease receptor density so that agonist affinity constants could be determined functionally. Treatment of tissues with BAAM decreased the functional potencies of agonists. Higher concentrations of BAAM decreased the maximum tissue response. Affinity constants for agonists calculated after BAAM treatment were compared to affinity constants determined from binding studies done under conditions designed to promote high or low affinity agonist binding. Functional affinity constants for isoproterenol and salbutamol agreed with the low affinity binding constants, suggesting that the low affinity form of the receptor initiates the functional response. Because acute denervation of vasa deferentia did not alter the density of /sup 125/IPIN binding sites, the sites are probably post-junctional. Chronic infusion of isoproterenol reduced the potency of isoproterenol, the maximum tissue response, and the receptor density. These results suggest that ..beta..-adrenergic receptor density and responsiveness in rat vas deferens are not affected by removing catecholamine sources, but receptor density and responsiveness can be decreased by increasing agonist concentration at the receptor.

  2. A Further Measurement of the beta-Delayed alpha-Particle Emission of 16N

    CERN Document Server

    III, R H F; McDonald, J E; Wilds, E L


    We measured the beta-delayed alpha-particle emission spectrum of 16N with a sensitivity for beta-decay branching ratios of the order of 10-10. The 16N nuclei were produced using the d(15N,16N)p reaction with 70 MeV 15N beams and a deuterium gas target 7.5 cm long at a pressure of 1250 torr. The 16N nuclei were collected (over 10 s) using a thin aluminum foil with an areal density of 180 mu g/cm2 tilted at 7 Deg with respect to the beam. The activity was transferred to the counting area by means of a stepping motor in less than 3 s with the counting carried out over 8 s. The beta-delayed alpha-particles were measured using a time of flight method to achieve a sufficiently low background. Standard calibration sources (148Gd, 241Am, 208,209Po, and 227Ac) as well as alpha-particles and 7Li from the 10B(n,alpha)7Li reaction were used for an accurate energy calibration. The energy resolution of the catcher foil (180-220 keV) was calculated and the time of flight resolution (3-10 nsec) was measured using the beta-de...

  3. Beta-delayed neutron spectroscopy of spherical and deformed neutron emitters with VANDLE (United States)

    King, Thomas; Gross, C. J.; Grzywacz, R. K.; Paulauskas, S. V.; Rykaczewski, K. P.; Stracener, D. W.,; Taylor, S. Z.; Vandle Collaboration


    For many neutron-rich isotopes, the main decay mode is through beta-delayed neutron and gamma emission. Neutron and gamma coincidences provide information necessary to extract the beta-strength distribution. These distributions are inputs to test nuclear models needed for r-process modeling. The detailed data on beta decay feeding to neutron-unbound states are used to calculate reactor decay heat and understand the antineutrino spectrum. A series of measurements with selective ion sources was performed at the On-Line Test Facility (OLTF) at Oak Ridge National Laboratory with the Versatile Array of Neutron Detectors at Low Energy (VANDLE). These experiments revisited decays of spherical and deformed isotopes produced in proton induced fission of 238U, which included beta delayed precursors of bromine, rubidium, cesium, and iodine. Unique data sets with neutron and gamma ray coincidences were collected. Achieving high coincidence efficiency required the addition of high-efficiency gamma-ray detectors consisting of 16 LaBr3 crystals (HAGRiD) and a large volume set of NaI detectors to VANDLE. Preliminary results will be presented. This research was sponsored by DOE under Contracts DE-FG52-08NA2855, DE-AC05-00OR22725 and DE-FG02-96ER40983.

  4. Development of Simultaneous Beta-and-Coincidence-Gamma Imager for Plant Imaging Research

    Energy Technology Data Exchange (ETDEWEB)

    Tai, Yuan-Chuan [Washington Univ., St. Louis, MO (United States). School of Medicine


    The goal of this project is to develop a novel imaging system that can simultaneously acquire beta and coincidence gamma images of positron sources in thin objects such as leaves of plants. This hybrid imager can be used to measure carbon assimilation in plants quantitatively and in real-time after C-11 labeled carbon-dioxide is administered. A better understanding of carbon assimilation, particularly under the increasingly elevated atmospheric CO2 level, is extremely critical for plant scientists who study food crop and biofuel production. Phase 1 of this project is focused on the technology development with 3 specific aims: (1) develop a hybrid detector that can detect beta and gamma rays simultaneously; (2) develop an imaging system that can differentiate these two types of radiation and acquire beta and coincidence gamma images in real-time; (3) develop techniques to quantify radiotracer distribution using beta and gamma images. Phase 2 of this project is to apply technologies developed in phase 1 to study plants using positron-emitting radionuclide such as 11C to study carbon assimilation in biofuel plants.

  5. Beta-lactamases of Mycobacterium tuberculosis and Mycobacterium kansasii. (United States)

    Segura, C; Salvadó, M


    Re-emergence of infectious diseases caused by mycobacteria as well as the emergence of multiresistant strains of Mycobacterium has promoted the research on the use of beta-lactames in the treatment of such diseases. Mycobacteria produce beta-lactamases: M. tuberculosis produces a wide-spectrum beta-lactamase whose behaviour mimicks those of Gram-negative bacteria. M. kansasii produces also beta-lactamase which can be inhibited by clavulanic acid. An overview on beta-lactamases from both species is reported.

  6. Anxiolytics not acting at the benzodiazepine receptor: beta blockers. (United States)

    Tyrer, P


    1. Although there is clear evidence for many controlled trials in the past 25 years that beta blockers are effective in anxiety disorders clear indications for their use are lacking. 2. The balance of evidence suggests that the mechanism of action of beta-blocking drugs is through peripheral blockade of beta-mediated symptoms. 3. Most evidence to the efficacy of beta-blockers comes from study of their use in generalized anxiety and in acute stress. 4. Because beta-blockers carry no risks of pharmacological dependence they may be preferred to many other anti-anxiety drugs.

  7. Probing the N = Z Line via {beta} Decay

    Energy Technology Data Exchange (ETDEWEB)

    Markku Oinonen


    This contribution reports several beta-decay studies performed at ISOLDE On-Line Mass Separator at CERN recently for nuclei close to N = Z line. Beta decay of {sup 58}Zn provides a possibility to compare Gamow-Teller strength extracted from complementary beta-decay studies and charge-exchange reactions. Measurement on beta-decay half-life of {sup 70}Kr shows importance of experimental information in modeling the path of the astrophysical rp process. Decay of {sup 71}Kr is an example of a mirror beta decay and extends the systematics of these particular decays towards highly deformed region close to A = 80.

  8. Factors affecting drug adsorption on beta zeolites. (United States)

    Pasti, Luisa; Sarti, Elena; Cavazzini, Alberto; Marchetti, Nicola; Dondi, Francesco; Martucci, Annalisa


    The adsorption behaviour of three commonly used drugs, namely ketoprofen, hydrochlorothiazide and atenolol, from diluted aqueous solutions on beta zeolites with different SiO2/Al2O3 ratio (i.e. 25, 38 and 360) was investigated by changing the ionic strength and the pH, before and after thermal treatment of the adsorbents. The selective adsorption of drugs was confirmed by thermogravimetry and X-ray diffraction. The adsorption capacity of beta zeolites was strongly dependent on both the solution pH and the alumina content of the adsorbent. Such a remarkable difference was interpreted as a function of the interactions between drug molecules and zeolite surface functional groups. Atenolol was readily adsorbed on the less hydrophobic zeolite, under pH conditions in which electrostatic interactions were predominant. On the other hand, ketoprofen adsorption was mainly driven by hydrophobic interactions. For undissociated molecules the adsorption capability increased with the increase of hydrophobicity.

  9. Beta-haemolytic streptococci in acute pharyngitis. (United States)

    Boukadida, J; Hannechi, N; Boukadida, N; Ben Said, H; Elmherbech, H; Errai, S


    To determine the role and importance of beta-haemolytic streptococci in acute pharyngitis and its relative susceptibility to antibiotics, we cultured samples from 143 patients (age range: 3-72 years) who presented over a 5-month period in 2001 at three primary health care centres in Sousse, Tunisia. The cultures yielded 80 beta-haemolytic streptococci (59 group A streptococci and 21 non-group A streptococci). All strains were susceptible to benzylpenicillin, amoxicillin, chloramphenicol, rifampicin and pristinamycin. Susceptibility was variable in erythromycin, tetracycline, fosfomycin, telithromycin and levofloxacin. Minimum inhibitory concentrations were determined by E-test for penicillin, erythromycin and levofloxacin. Our results confirm that penicillin is still the reference treatment for acute pharyngitis. However, to minimize the potential for complications arising from its use, continued vigilance is required.

  10. The 8Li Calibration Source for the Sudbury Neutrino Obervatory

    CERN Document Server

    Tagg, N J; Sur, B; Earle, E D; Helmer, R L; Jonkmans, G; Moffat, B A; Simpson, J J


    A calibration source employing 8Li (t_1/2 = 0.838s) has been developed for use with the Sudbury Neutrino Observatory (SNO). This source creates a spectrum of beta particles with an energy range similar to that of the SNO 8B solar neutrino signal. The source is used to test the SNO detector's energy response, position reconstruction and data reduction algorithms. The 8Li isotope is created using a deuterium-tritium neutron generator in conjunction with a 11B target, and is carried to a decay chamber using a gas/aerosol transport system. The decay chamber detects prompt alpha particles by gas scintillation in coincidence with the beta particles which exit through a thin stainless steel wall. A description is given of the production, transport, and tagging techniques along with a discussion of the performance and application of the source.

  11. Autoradiographic localization of beta-adrenoreceptors in rat uterus

    Energy Technology Data Exchange (ETDEWEB)

    Tolszczuk, M.; Pelletier, G.


    The inhibitory effects of catecholamines on uterine smooth muscle are known to be mediated through beta-adrenergic receptors. To investigate further the distribution of these receptors in the rat uterus, we utilized in vitro autoradiography using ( SVI)-cyanopindolol (CYP), a specific beta-receptor ligand that has equal activity for both beta 1- and beta 2-receptor subtypes. The specificity of the labeling and the characterization of receptor subtypes in different cell types were achieved by displacement of radioligand with increasing concentrations of zinterol, a beta-adrenergic agonist with preferential affinity for the beta 2-adrenoreceptor subtype, and practolol, a beta-adrenergic antagonist that binds preferentially to the beta 1-subtype. Quantitative estimation of ligand binding was performed by densitometry. It was shown that the vast majority of beta-adrenoreceptors were of the beta 2-subtype and were found in high concentration not only in the myometrium but also in the endometrial and serosal epithelia. Specific labeling was also observed in glandular elements. These results suggest that beta-adrenoreceptors might be involved in different functions in the uterus.

  12. Beta Testing of Persistent Passive Acoustic Monitors (United States)


    solution. This translates into longer deployments on platforms such as gliders with limited hotel load. 2. the DMON is specifically designed for low...filter or filter bank may improve performance • Glider and Profiler motors and pumps are noisy , however duty cycle of noise is low. Therefore they are...power making it ideal for low hotel load autonomous vehicles like gliders. The format shown here was provided to beta-test clients working on gliders and

  13. SPL and Beta Beams to the Frejus

    CERN Document Server

    Mezzetto, M


    Physics potential of a conventional neutrino beam generated by the 2.2 GeV, 4MW, Superconducting Proton Linac and of a Beta Beam fired to a gigantic water Ccaronerenkov detector hosted below Frejus, 130 km away from CERN, are briefly summarized. theta/sub 13/ sensitivity could be improved by up to 3 orders of magnitude with respect to the present experimental limit and a first sensitive search for leptonic CP violation could be performed.

  14. A background free double beta decay experiment


    Giomataris, Ioannis


    We present a new detection scheme for rejecting backgrounds in neutrino less double beta decay experiments. It relies on the detection of Cherenkov light emitted by electrons in the MeV region. The momentum threshold is tuned to reach a good discrimination between background and good events. We consider many detector concepts and a range of target materials. The most promising is a high-pressure 136Xe emitter for which the required energy threshold is easily adjusted. Combination of this conc...

  15. Alpha-beta bidirectional associative memories


    María Elena Acevedo Mosqueda; Cornelio Yáñez Márquez


    Most models of Bidirectional associative memories intend to achieve that all trained pattern correspond to stable states; however, this has not been possible. Also, none of the former models has been able to recall all the trained patterns. In this work we introduce a new model of bidirectional associative memory which is not iterative and has no stability problems. It is based on the Alpha-Beta associative memories. This model allows perfect recall of all trained patterns, with no ambiguity ...

  16. High-{beta} disruption in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Park, W.; Fredrickson, E.D.; Janos, A. [and others


    Three dimensional MHD simulations of high-{beta} plasmas show that toroidally localized high-n ballooning modes can be driven unstable by the local pressure steepening which arises from the evolution of low-n modes. Nonlinearly, the high-n mode becomes even more localized and produces a strong local pressure bulge which destroys the flux surfaces resulting in a thermal quench. The flux surfaces then recover temporarily but now contain large magnetic islands. This scenario is supported by experimental data.

  17. Inhibition of human and rat 11beta-hydroxysteroid dehydrogenase type 1 by 18beta-glycyrrhetinic acid derivatives. (United States)

    Su, Xiangdong; Vicker, Nigel; Lawrence, Harshani; Smith, Andrew; Purohit, Atul; Reed, Michael J; Potter, Barry V L


    11beta-Hydroxysteroid dehydrogenase type 1 (11beta-HSD1) plays an important role in regulating the cortisol availability to bind to corticosteroid receptors within specific tissue. Recent advances in understanding the molecular mechanisms of metabolic syndrome indicate that elevation of cortisol levels within specific tissues through the action of 11beta-HSD1 could contribute to the pathogenesis of this disease. Therefore, selective inhibitors of 11beta-HSD1 have been investigated as potential treatments for metabolic diseases, such as diabetes mellitus type 2 or obesity. Here we report the discovery and synthesis of some 18beta-glycyrrhetinic acid (18beta-GA) derivatives (2-5) and their inhibitory activities against rat hepatic11beta-HSD1 and rat renal 11beta-HSD2. Once the selectivity over the rat type 2 enzyme was established, these compounds' ability to inhibit human 11beta-HSD1 was also evaluated using both radioimmunoassay (RIA) and homogeneous time resolved fluorescence (HTRF) methods. The 11-modified 18beta-GA derivatives 2 and 3 with apparent selectivity for rat 11beta-HSD1 showed a high percentage inhibition for human microsomal 11beta-HSD1 at 10 microM and exhibited IC50 values of 400 and 1100 nM, respectively. The side chain modified 18beta-GA derivatives 4 and 5, although showing selectivity for rat 11beta-HSD1 inhibited human microsomal 11beta-HSD1 with IC50 values in the low micromolar range.

  18. Serum beta2-microglobulin in cadmium exposed workers. (United States)

    Piscator, M


    In cadmium exposed workers with renal tubular dysfunction the determination of beta2m in urine is an important diagnostic test. Cadmium exposure's influence on serum beta2m levels and its relationship to urinary excretion of beta2m were studied in 24 cadmium exposed workers with normal serum creatinine levels (less than 10 mg/l)) and no obvious tubular dysfunction. With increasing blood levels of cadmium beta2m was found to increase in serum. There was no concomitant increase in the urinary excretion of beta2m. Serum beta2m was not dependent on serum creatinine within the range studied. The results suggest that for evaluating renal glomerular function in cadmium exposed workers, it might be better to use the serum creatinine level, creatinine clearance or inulin clearance since beta2m might give some false positive results.

  19. Reinvestigation of the beta-decay of {sup 110}Mo

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J.C.; Dendooven, P.; Hankonen, S.; Huikari, J.; Jokinen, A.; Kolhinen, V.S.; Lhersonneau, G.; Nieminen, A.; Peraejaervi, K.; Rinta-Antila, S.; Aeystoe, J. [Department of Physics, University of Jyvaeskylae, FIN-40351, Jyvaeskylae (Finland)


    The beta-decay of the neutron-rich nucleus {sup 110}Mo, separated by the IGISOL on-line mass separator from other fission products, has been investigated by using beta-gamma and gamma-gamma coincidence techniques. The decay scheme of {sup 110}Mo has been revised, including 3 new excited states and 7 new {gamma} transitions in {sup 110}Tc. The {beta}-feedings were measured and log ft values and B(GT) values were deduced based on a Q{sub {beta}}-value from systematics. Three excited 1{sup +} states in {sup 110}Tc fed by spin-flip allowed-unhindered beta transitions were identified. The deduced beta-decay strengths are compared with the Gamow-Teller strength distribution obtained from a macroscopic-microscopic calculation. The role of the asymptotic quantum numbers in the context of the allowed beta-decay is discussed. (orig.)

  20. Genetic analysis of beta1 integrin "activation motifs" in mice

    DEFF Research Database (Denmark)

    Czuchra, Aleksandra; Meyer, Hannelore; Legate, Kyle R


    tails, leading to tail separation and integrin activation. We analyzed mice in which we mutated the tyrosines of the beta1 tail and the membrane-proximal aspartic acid required for the salt bridge. Tyrosine-to-alanine substitutions abolished beta1 integrin functions and led to a beta1 integrin......-null phenotype in vivo. Surprisingly, neither the substitution of the tyrosines with phenylalanine nor the aspartic acid with alanine resulted in an obvious defect. These data suggest that the NPXY motifs of the beta1 integrin tail are essential for beta1 integrin function, whereas tyrosine phosphorylation......Akey feature of integrins is their ability to regulate the affinity for ligands, a process termed integrin activation. The final step in integrin activation is talin binding to the NPXY motif of the integrin beta cytoplasmic domains. Talin binding disrupts the salt bridge between the alpha/beta...

  1. The Dust and Gas Around beta Pictoris

    CERN Document Server

    Chen, C H; Bohac, C; Kim, K H; Watson, D M; van Cleve, J; Houck, J; Stapelfeldt, K; Werner, M W; Rieke, G; Su, K; Marengo, M; Backman, D; Beichman, C; Fazio, G


    We have obtained Spitzer IRS 5.5 - 35 micron spectroscopy of the debris disk around beta Pictoris. In addition to the 10 micron silicate emission feature originally observed from the ground, we also detect the crystalline silicate emission bands at 28 micron and 33.5 micron. This is the first time that the silicate bands at wavelengths longer than 10 micron have ever been seen in the beta Pictoris disk. The observed dust emission is well reproduced by a dust model consisting of fluffy cometary and crystalline olivine aggregates. We searched for line emission from molecular hydrogen and atomic [S I], Fe II, and Si II gas but detected none. We place a 3 sigma upper limit of <17 Earth masses on the H2 S(1) gas mass, assuming an excitation temperature of Tex = 100 K. This suggests that there is less gas in this system than is required to form the envelope of Jupiter. We hypothesize that some of the atomic Na I gas observed in Keplerian rotation around beta Pictoris may be produced by photon-stimulated desorpti...

  2. Beta decay of {sup 101}Sn

    Energy Technology Data Exchange (ETDEWEB)

    Kavatsyuk, O.; Kavatsyuk, M. [Gesellschaft fuer Schwerionenforschung, Damrstadt (Germany); National Taras Shevchenko Univ. of Kyiv (Ukraine); Mazzocchi, C. [Gesellschaft fuer Schwerionenforschung, Damrstadt (Germany); Univ. of Tennessee, Knoxville (United States); Janas, Z.; Karny, M.; Miernik, K.; Plochocki, A.; Zylicz, J. [University of Warsaw (Poland); Banu, A.; Becker, F.; Bruechle, W.; Doering, J.; Gorska, M.; Grawe, H.; Klepper, O.; Kirchner, R.; Plettner, C.; Roeckl, E.; Schaedel, M. [Gesellschaft fuer Schwerionenforschung, Darmstadt, Darmstadt (Germany); Batist, L. [St. Petersburg Nuclear Physics Institute (Russian Federation); Blazhev, A. [Gesellschaft fuer Schwerionenforschung, Damrstadt (Germany); Univ. of Sofia (Bulgaria); Faestermann, T. [Technische Universitaet Muenchen (Germany); Jungclaus, A. [Instituto Estructura de la Materia, CSIC (Spain); Departamento de Fisica Teorica, UAM, Madrid (Spain); La Commara, M.; Romoli, M. [Universita ' ' Federico II' ' , Napoli (Italy); INFN, Napoli (Italy); Mukha, I. [Gesellschaft fuer Schwerionenforschung, Damrstadt (Germany); Kurchatov Inst., Moscow (Russian Federation); Rykaczewski, K. [Oak Ridge National Laboratory, Oak Ridge (United States); Schmidt, K. [Continental Teves AG and Co., Frankfurt am Main (Germany); Schwengner, R. [Institut fuer Kern- und Hadronenphysik, Forschungszentrum Rossendorf, Dresden (Germany)


    The {beta} decay of the very neutron-deficient isotope {sup 101}Sn was studied at the GSI on-line mass separator using silicon detectors for recording charged particles and germanium detectors for {gamma}-ray spectroscopy. Based on the {beta}-delayed proton data the production cross-section of {sup 101}Sn in the {sup 50}Cr+{sup 58}Ni fusion-evaporation reaction was determined to be about 60nb. The half-life of {sup 101}Sn was measured to be 1.9(3)s. For the first time {beta}-delayed {gamma}-rays of {sup 101}Sn were tentatively identified, yielding weak evidence for a cascade of 352 and 1065keV transitions in {sup 101}In. The results for the {sup 101}Sn decay as well as those from previous work on the {sup 103}Sn decay are discussed by comparing them to predictions obtained from shell model calculations employing a new interaction in the {sup 88}Sr to {sup 132}Sn model space. (orig.)

  3. 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

  4. Beta-carotene and the application of transcriptomics in risk-benefit evaluation of natural dietary components



    Beta-carotene is a natural food component that is present in fruits and vegetables and is also used as a food colorant and a supplement. Beta-carotene is an anti-oxidant and a source of vitamin A. It is endowed with health beneficial properties, but a number of studies showed that with high intakes it may increase the risk for lung cancer in at risk individuals (heavy smokers, asbestos workers and alcohol users). To establish the window of benefit, it is necessary to identify early markers of...

  5. Open Source

    Institute of Scientific and Technical Information of China (English)


    一场秋雨一场凉,开源社区的气温却丝毫没有降。刚在北京闭幕的“2006中国开源世界高峰论坛”足以让世界侧目。国际大师云集是最大的亮点,很多熟悉的名字:Andrew Morton(Linux内核开发大师及2.6版本监护人)、Brian Behlendorf(Apache创始人)、David Axmark(MySQL创始人)、Marc Fleury(JBoss创始人)、Larry Augustin(Source Forge创始人)等;其次是中国政府、学术界的支持,包括国家信产部陈英司长和中国工程院倪光南院士、沈昌祥院士等;当然.少不了诸多跨国公司和国内知名企业的参与。

  6. Sources manuscrites



    I. SOURCES CONSULTÉES AUX ARCHIVES NATIONALES Série E 1. Minutes d’arrêts du Conseil, arrêts simples en finances 1602 : E 4a, E 4b. 1605 : E 8a, E 8b, E 8c-9a, E 9b, E 9c. 1608 : E 16a, E 16b, E 18a, E 18b, E 19a, E 19b. 1620 : E 63a E 63b, E 64a, E 64b-65a, E 65b. 1689 : E 579a, E 579b, E 580, E 581, E 582, E 583, E 584a, E 584b, E 585a, E 585b, E 586a, E 586b 1750 : E 1260a E 1260b, E 1261a E 1261b, E 1262a, E 1262b, E 1262e, E 1263a, E 1263b, E 1264a, E 1264b, E 1265a, E 1265b, E 1266a, E ...

  7. Effects of calcium impurity on phase relationship, ionic conductivity and microstructure of Na$^{+}$-$\\beta/beta"$-alumina solid electrolyte

    Indian Academy of Sciences (India)



    Ca-doped Na$^{+}$-$\\beta/beta"$-alumina was synthesized using a solid-state reaction. The changes in the properties of Na$^{+}$-$\\beta/beta"$-alumina resulting from the presence of Ca impurity were studied. Ca (0–5 wt%) was added to the respective samples, which were then sintered. The specimens were characterized using X-ray diffraction, scanningelectron microscopy, densimetry and impedance analysis. In the sintered specimens, the $\\beta"$-alumina phase fraction decreased as Ca content increased, whereas the relative sintered density increased. The surface morphology of Cadoped Na$^{+}$-$\\beta/beta"$-alumina specimens showed a Ca-rich layer, which was the main cause of increase in the specificresistance.

  8. Beta-blockers and heart failure. (United States)

    Cruickshank, John M


    The life-time risk of developing HF is about 20% (40% if hypertension present). With increasing longevity in the developed world the burden of HF (hospitalisation) is set to increase over the next 10-20 years. CAD and hypertension are the two main causes of HF; CAD (and obesity) in the case of systolic HF and hypertension in the case of diastolic HF (mainly in the elderly). BB have become the corner-stone (alongside ACE-inhibitors) in the treatment of systolic HF. Bisoprolol, metoprolol and carvedilol (on an ACE-inhibitor background) have reduced all-cause death by 34-5%. The presence of intrinsic sympathomemetic activity (xamoterol, bucindolol, nebivolol) diminishes efficacy in the treatment of systolic HF. First-line bisoprolol has proved "non-inferior" to first-line enalapril in reducing all-cause death and is probably superior in reducing sudden death. The main mode of action of BB in treating systolic HF is inhibition of chronic beta-1 stimulation-induced myocardial apoptosis/necrosis/inflammation. The combination of pure beta-1 blockade (low-dose bisoprolol) and pure beta-2 blockade (clenbuterol) may prove invaluable in the treatment of end-stage systolic HF (thus avoiding cardiac transplantation). The appropriate treatment of diastolic HF has yet to be determined. Beta-blockade is effective in the prevention of HF i) in the post-MI period and ii) as first-line agents in the treatment of young/middle-aged hypertension and as second-line agents (to first-line diuretics) in the treatment of elderly systolic hypertension. BB are highly effective in reversing LVH in young/middle-aged hypertensives (LVH pre-disposes to HF in young/middle-aged hypertension) and are (bisoprolol) at least as good as ACE-inhibitors. Choice of BB is important as benefit is not a class-effect. ISA (xamoterol, bucindolol, nebivolol) markedly diminishes efficacy. The choice is between bisoprolol, metoprolol succinate and carvedilol for optimal efficacy. Adverse reactions are associated

  9. Utilization of UF-permeate for production of beta-galactosidase by lactic acid bacteria. (United States)

    Murad, H A; Refaea, R I; Aly, E M


    Four lactobacilli strains (Lactobacillus bulgaricus, Lactobacillus acidophilus, Lactobacilus casei and Lactobacillus reuteri) were grown in MRS broth and three lactococci strains (Streptococcus thermophilus, Lactococcus lactis subsp. Lactis and Lactococcus lactis subsp. lactis biovar. diacetilactis) were grown in M17 broth. L. reuteri and S. thermophilus were chosen on the basis of the best mean beta-galactosidase activity of 10.44 and 10.01 U/ml respectively, for further studies on permeate-based medium. The maximum production of beta-galactosidase by L. reuteri was achieved at lactose concentration of 6%, initial pH 5.0-7.5, ammonium phosphate as nitrogen source at a concentration of 0.66 g N/L and incubation temperature at 30 degrees C/24 hrs to give 6.31 U/ml. While in case of S. thermophilus, maximum beta-galactosidase production was achieved at 10% lactose concentration of permeate medium, supplemented with phosphate buffer ratio of 0.5:0.5 (KH2PO4:K2HPO4, g/L), at initial pH 6.0-6.5, ammonium phosphate (0.66g N/L) as nitrogen source and incubation temperature 35 degrees C for 24 hrs to give 7.85 U/ml.

  10. Orbital Constraints on the (beta) Pic Inner Planet Candidate with Keck Adaptive Optics

    Energy Technology Data Exchange (ETDEWEB)

    Fitzgerald, M P; Kalas, P G; Graham, J R


    A point source observed 8AU in projection from {beta} Pictoris in L{prime} (3.8 {micro}m) imaging in 2003 has been recently presented as a planet candidate. Here we show the results of L{prime}-band adaptive optics imaging obtained at Keck Observatory in 2008. We do not detect {beta} Pic b beyond a limiting radius of 0.29-inch, or 5.5AU in projection, from the star. If {beta} Pic b is an orbiting planet, then it has moved {ge} 0.12-inch (2.4AU in projection) closer to the star in the five years separating the two epochs of observation. We examine the range of orbital parameters consistent with the observations, including likely bounds from the locations of previously inferred planetesimal belts. We find a family of low-eccentricity orbits with semimajor axes {approx} 8-9AU that are completely allowed, as well as a broad region of orbits with e {approx}< 0.2, a {approx}> 10AU that are allowed if the apparent motion of the planet was towards the star in 2003. We compare this allowed space with predictions of the planetary orbital elements from the literature. Additionally, we show how similar observations in the next several years can further constrain the space of allowed orbits. Non-detections of the source through 2013 will exclude the interpretation of the candidate as a planet orbiting between the 6.4 and 16AU planetesimal belts.

  11. A new dedicated {beta}-NMR/{beta}-NQR setup for LISE-GANIL

    Energy Technology Data Exchange (ETDEWEB)

    De Rydt, M., E-mail: marieke.derydt@fys.kuleuven.b [Instituut voor Kern- en Stralingsfysica, K.U. Leuven, Celestijnenlaan 200D, B-3001 Leuven (Belgium); Lozeva, R.; Vermeulen, N. [Instituut voor Kern- en Stralingsfysica, K.U. Leuven, Celestijnenlaan 200D, B-3001 Leuven (Belgium); Oliveira Santos, F. de; Grevy, S. [Grand Accelerateur National d' Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, B.P. 55027, F-14076 Caen Cedex 5 (France); Himpe, P. [Instituut voor Kern- en Stralingsfysica, K.U. Leuven, Celestijnenlaan 200D, B-3001 Leuven (Belgium); Stoedel, C.; Thomas, J.C. [Grand Accelerateur National d' Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, B.P. 55027, F-14076 Caen Cedex 5 (France); Vingerhoets, P.; Neyens, G. [Instituut voor Kern- en Stralingsfysica, K.U. Leuven, Celestijnenlaan 200D, B-3001 Leuven (Belgium)


    A new {beta}-NMR/{beta}-NQR setup is developed to study nuclear magnetic dipole moments and electric quadrupole moments at the LISE fragment separator at GANIL. Two key elements make the new design very powerful: the homogeneous magnet and the strong radio-frequency amplifier. The combination of both makes it possible to examine a broad spectrum of magnetic dipole and electric quadrupole moments. Several factors have an influence on the detection efficiency and on the sensitivity of the setup to observe a resonant change in the {beta}-asymmetry: the thickness and the tilting angle of the implantation crystal, the material in the vacuum chamber, the applied magnetic field and the Q{sub b}eta-value of the decaying nuclei. A detailed study of these effects is made using a dedicated GEANT4 Monte Carlo simulation code.

  12. Beta-decay rate and beta-delayed neutron emission probability of improved gross theory (United States)

    Koura, Hiroyuki


    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

  13. In vitro proliferation of adult human beta-cells.

    Directory of Open Access Journals (Sweden)

    Sabine Rutti

    Full Text Available A decrease in functional beta-cell mass is a key feature of type 2 diabetes. Glucagon-like peptide 1 (GLP-1 analogues induce proliferation of rodent beta-cells. However, the proliferative capacity of human beta-cells and its modulation by GLP-1 analogues remain to be fully investigated. We therefore sought to quantify adult human beta-cell proliferation in vitro and whether this is affected by the GLP-1 analogue liraglutide.Human islets from 7 adult cadaveric organ donors were dispersed into single cells. Beta-cells were purified by FACS. Non-sorted cells and the beta-cell enriched ("beta-cells" population were plated on extracellular matrix from rat (804G and human bladder carcinoma cells (HTB9 or bovine corneal endothelial ECM (BCEC. Cells were maintained in culture+/-liraglutide for 4 days in the presence of BrdU.Rare human beta-cell proliferation could be observed either in the purified beta-cell population (0.051±0.020%; 22 beta-cells proliferating out of 84'283 beta-cells counted or in the non-sorted cell population (0.055±0.011%; 104 proliferating beta-cells out of 232'826 beta-cells counted, independently of the matrix or the culture conditions. Liraglutide increased human beta-cell proliferation on BCEC in the non-sorted cell population (0.082±0.034% proliferating beta-cells vs. 0.017±0.008% in control, p<0.05.These results indicate that adult human beta-cell proliferation can occur in vitro but remains an extremely rare event with these donors and particular culture conditions. Liraglutide increases beta-cell proliferation only in the non-sorted cell population and only on BCEC. However, it cannot be excluded that human beta-cells may proliferate to a greater extent in situ in response to natural stimuli.

  14. Thymosin Beta 4 and Thymosin Beta 10 Expression in Hepatocellular Carcinoma (United States)

    Theunissen, W.; Fanni, D.; Nemolato, S.; Di Felice, E.; Cabras, T.; Gerosa, C.; Van Eyken, P.; Messana, I.; Castagnola, M.; Faa, G.


    Thymosin beta 4 (Tβ4) and thymosin beta 10 (Tβ10) are two members of the beta-thymosin family involved in many cellular processes such as cellular motility, angiogenesis, inflammation, cell survival and wound healing. Recently, a role for beta-thymosins has been proposed in the process of carcinogenesis as both peptides were detected in several types of cancer. The aim of the present study was to investigate the expression pattern of Tβ4 and Tβ10 in hepatocellular carcinoma (HCC). To this end, the expression pattern of both peptides was analyzed in liver samples obtained from 23 subjects diagnosed with HCC. Routinely formalin-fixed and paraffin-embedded liver samples were immunostained by indirect immunohistochemistry with polyclonal antibodies to Tβ4 and Tβ10. Immunoreactivity for Tβ4 and Tβ10 was detected in the liver parenchyma of the surrounding tumor area. Both peptides showed an increase in granular reactivity from the periportal to the periterminal hepatocytes. Regarding HCC, Tβ4 reactivity was detected in 7/23 cases (30%) and Tβ10 reactivity in 22/23 (96%) cases analyzed, adding HCC to human cancers that express these beta-thymosins. Intriguing finding was seen looking at the reactivity of both peptides in tumor cells infiltrating the surrounding liver. Where Tβ10 showed a strong homogeneous expression, was Tβ4 completely absent in cells undergoing stromal invasion. The current study shows expression of both beta-thymosins in HCC with marked differences in their degree of expression and frequency of immunoreactivity. The higher incidence of Tβ10 expression and its higher reactivity in tumor cells involved in stromal invasion indicate a possible major role for Tβ10 in HCC progression. PMID:24704991

  15. Thymosin beta 4 and thymosin beta 10 expression in hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    W. Theunissen


    Full Text Available Thymosin beta 4 (Tβ4 and thymosin beta 10 (Tβ10 are two members of the beta-thymosin family involved in many cellular processes such as cellular motility, angiogenesis, inflammation, cell survival and wound healing. Recently, a role for beta-thymosins has been proposed in the process of carcinogenesis as both peptides were detected in several types of cancer. The aim of the present study was to investigate the expression pattern of Tβ4 and Tβ10 in hepatocellular carcinoma (HCC. To this end, the expression pattern of both peptides was analyzed in liver samples obtained from 23 subjects diagnosed with HCC. Routinely formalin-fixed and paraffin-embedded liver samples were immunostained by indirect immunohistochemistry with polyclonal antibodies to Tβ4 and Tβ10. Immunoreactivity for Tβ4 and Tβ10 was detected in the liver parenchyma of the surrounding tumor area. Both peptides showed an increase in granular reactivity from the periportal to the periterminal hepatocytes. Regarding HCC, Tβ4 reactivity was detected in 7/23 cases (30% and Tβ10 reactivity in 22/23 (97% cases analyzed, adding HCC to human cancers that express these beta-thymosins. Intriguing finding was seen looking at the reactivity of both peptides in tumor cells infiltrating the surrounding liver. Where Tβ10 showed a strong homogeneous expression, was Tβ4 completely absent in cells undergoing stromal invasion. The current study shows expression of both beta-thymosins in HCC with marked differences in their degree of expression and frequency of immunoreactivity. The higher incidence of Tβ10 expression and its higher reactivity in tumor cells involved in stromal invasion indicate a possible major role for Tβ10 in HCC progression.

  16. 21beta-Hydroxy-oleanane-type triterpenes from Hippocratea excelsa. (United States)

    Cáceres-Castillo, David; Mena-Rejón, Gonzalo J; Cedillo-Rivera, Roberto; Quijano, Leovigildo


    Stem bark of Hippocratea excelsa afforded six pentacyclic triterpenes, five oleanane and one ursane types. They were identified as 11beta,21beta-dihydroxy-olean-12-ene-3-one (2), 3alpha,11alpha,21beta-trihydroxy-olean-12-ene (3), 3alpha,21beta-dihydroxy-11alpha-methoxy-olean-12-ene (4), 3alpha,21beta-dihydroxy-olean-9(11),12-diene (5), 3alpha,21beta-dihydroxy-olean-12-ene (6) and 3alpha,21beta-dihydroxy-11alpha-methoxy-urs-12-ene, isolated as its diacetate derivative (7), as well as 3alpha,21beta-dihydroxy-olean-12-ene (1) previously isolated from the root bark. The known alpha- and beta-amyrin, oleanoic and ursolic acids, trans-polyisoprene, and the ubiquitous beta-sitosterol were also isolated. Structures were elucidated on the basis of spectroscopic analyses, including homo- and heteronuclear correlation NMR experiments (COSY, ROESY, HSQC and HMBC) and comparison with literature data. The antigiardial activity of compounds 2-5 was not significant.

  17. Metabolic Stress and Compromised Identity of Pancreatic Beta Cells (United States)

    Swisa, Avital; Glaser, Benjamin; Dor, Yuval


    Beta cell failure is a central feature of type 2 diabetes (T2D), but the molecular underpinnings of the process remain only partly understood. It has been suggested that beta cell failure in T2D involves massive cell death. Other studies ascribe beta cell failure to cell exhaustion, due to chronic oxidative or endoplasmic reticulum stress leading to cellular dysfunction. More recently it was proposed that beta cells in T2D may lose their differentiated identity, possibly even gaining features of other islet cell types. The loss of beta cell identity appears to be driven by glucotoxicity inhibiting the activity of key beta cell transcription factors including Pdx1, Nkx6.1, MafA and Pax6, thereby silencing beta cell genes and derepressing alternative islet cell genes. The loss of beta cell identity is at least partly reversible upon normalization of glycemia, with implications for the reversibility of T2D, although it is not known if beta cell failure reaches eventually a point of no return. In this review we discuss current evidence for metabolism-driven compromised beta cell identity, key knowledge gaps and opportunities for utility in the treatment of T2D.

  18. Comprehensive identification of single nucleotide polymorphisms associated with beta-lactam resistance within pneumococcal mosaic genes.

    Directory of Open Access Journals (Sweden)

    Claire Chewapreecha


    Full Text Available Traditional genetic association studies are very difficult in bacteria, as the generally limited recombination leads to large linked haplotype blocks, confounding the identification of causative variants. Beta-lactam antibiotic resistance in Streptococcus pneumoniae arises readily as the bacteria can quickly incorporate DNA fragments encompassing variants that make the transformed strains resistant. However, the causative mutations themselves are embedded within larger recombined blocks, and previous studies have only analysed a limited number of isolates, leading to the description of "mosaic genes" as being responsible for resistance. By comparing a large number of genomes of beta-lactam susceptible and non-susceptible strains, the high frequency of recombination should break up these haplotype blocks and allow the use of genetic association approaches to identify individual causative variants. Here, we performed a genome-wide association study to identify single nucleotide polymorphisms (SNPs and indels that could confer beta-lactam non-susceptibility using 3,085 Thai and 616 USA pneumococcal isolates as independent datasets for the variant discovery. The large sample sizes allowed us to narrow the source of beta-lactam non-susceptibility from long recombinant fragments down to much smaller loci comprised of discrete or linked SNPs. While some loci appear to be universal resistance determinants, contributing equally to non-susceptibility for at least two classes of beta-lactam antibiotics, some play a larger role in resistance to particular antibiotics. All of the identified loci have a highly non-uniform distribution in the populations. They are enriched not only in vaccine-targeted, but also non-vaccine-targeted lineages, which may raise clinical concerns. Identification of single nucleotide polymorphisms underlying resistance will be essential for future use of genome sequencing to predict antibiotic sensitivity in clinical microbiology.

  19. BETA. A code for {beta}{sub eff} measurement and analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Yuichi; Okajima, Shigeaki; Sakurai, Takeshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment


    The code BETA has been developed to calculate the following reactor physics parameters which are used for the {beta}{sub eff} measurement and analysis; Diven factor, Spatial correction factor (g-factor) for neutron correlation experiment, Adjoint weighted g-factor, Fission rate integrated in whole reactor and Adjoint weighted fission rate integrated in whole reactor: The code also calculates the effective delayed neutron fraction with different evaluated delayed neutron data. These parameters are calculated with using the forward and adjoint fluxes given by SLAROM, POPLARS or TWOTRAN-II. This report describes the input data and job control statements instructions, file requirements and sample input output data. (author)

  20. beta. -. gamma. directional correlations in the. beta. -decay of /sup 208/Tl

    Energy Technology Data Exchange (ETDEWEB)

    Rosso, O.A.; Krmpotic, F.; Szybisz, L.


    The relevance of the quenching effects induced by charge-exchange collective fields and excitations is discussed in the case of the ..beta..-..gamma.. angular correlations in the decay of /sup 208/Tl to the 5/sup -//sub 1/, 4/sup -//sub 1/ and 5/sup -//sub 2/ levels in /sup 208/Pb. It is found that, although these effects give rise to a large hindrance of the ..beta..-moments, they influence the anisotropy factor only very weakly. Satisfactory agreement between theoretical predictions and experimental data is obtained for all the transitions.

  1. Production of beta-xylanase and beta-xylosidase by the extremely halophilic archaeon Halorhabdus utahensis

    DEFF Research Database (Denmark)

    Wainø, M.; Ingvorsen, K.


    The extremely halophilic archaeon, Halorhabdus utahensis, isolated from the Great Salt Lake, Utah, produced beta-xylanase and beta-xylosidase activities. Both enzymes were active over a broad NaCl range from near zero to 30% NaCl when tested with culture broth. A broad NaCl optimum was observed......-xylosidase activity was optimal at 65degreesC. SDS-PAGE and zymogram techniques revealed the presence of two xylan-degrading proteins of approximately 45 and 67 kDa in culture supernatants. To our knowledge, this paper is the first report on hemicellulose-degrading enzymes produced by an extremely halophilic archaeon....

  2. A revised model for AMP-activated protein kinase structure: The alpha-subunit binds to both the beta- and gamma-subunits although there is no direct binding between the beta- and gamma-subunits. (United States)

    Wong, Kelly A; Lodish, Harvey F


    The 5'-AMP-activated protein kinase (AMPK) is a master sensor for cellular metabolic energy state. It is activated by a high AMP/ATP ratio and leads to metabolic changes that conserve energy and utilize alternative cellular fuel sources. The kinase is composed of a heterotrimeric protein complex containing a catalytic alpha-subunit, an AMP-binding gamma-subunit, and a scaffolding beta-subunit thought to bind directly both the alpha- and gamma-subunits. Here, we use coimmunoprecipitation of proteins in transiently transfected cells to show that the alpha2-subunit binds directly not only to the beta-subunit, confirming previous work, but also to the gamma1-subunit. Deletion analysis of the alpha2-subunit reveals that the C-terminal 386-552 residues are sufficient to bind to the beta-subunit. The gamma1-subunit binds directly to the alpha2-subunit at two interaction sites, one within the catalytic domain consisting of alpha2 amino acids 1-312 and a second within residues 386-552. Binding of the alpha2 and the gamma1-subunits was not affected by 400 mum AMP or ATP. Furthermore, we show that the beta-subunit C terminus is essential for binding to the alpha2-subunit but, in contrast to previous work, the beta-subunit does not bind directly to the gamma1-subunit. Taken together, this study presents a new model for AMPK heterotrimer structure where through its C terminus the beta-subunit binds to the alpha-subunit that, in turn, binds to the gamma-subunit. There is no direct interaction between the beta- and gamma-subunits.

  3. $\\beta$-delayed fission, laser spectroscopy and shape-coexistence studies with radioactive At beams

    CERN Multimedia

    We propose to study the $\\beta$-delayed fission, laser spectroscopy and radioactive decay of the newly available pure beams of neutron-deficient and neutron-rich astatine (Z=85) isotopes. The fission probability and the fission fragment distribution of the even-even isotopes $^{194,196}$Po following the $\\beta$-decay of the isotopes $^{194,196}$At will be studied with the Windmill setup. In-source laser spectroscopy will be performed on the entire astatine isotopic chain, using a combination of the Windmill setup, ISOLTRAP MR-ToF and ISOLDE Faraday. Radioactive decay data will be acquired at the Windmill setup throughout those studies and contribute to the global understanding of the phenomenon of shape coexistence in the neutron-deficient lead region.

  4. Physical aspects of the angle-beta concept in electron arc therapy

    Energy Technology Data Exchange (ETDEWEB)

    Pla, M.; Podgorsak, E.B.; Pla, C.; Freeman, C.R.; Souhami, L.; Guerra, J. (Department of Radiation Oncology, McGill University, Montreal, Quebec (Canada))


    A technique for the determination of treatment parameters that are required to achieve a desired depth dose distribution in electron arc therapy is discussed and a method for calculating isodose distributions is presented. Both the treatment technique and the dose calculation method rely on the angle beta concept, which uniquely describes the dependence of the radial percentage depth doses in electron arc therapy on the nominal field width, isocenter depth, and virtual source-axis distance. The angle beta concept is discussed in detail and the electron pseudo-arc therapy technique used at McGill is described. Also presented is the method used to achieve dose homogeneity in target volumes treated with the pseudo-arc technique.

  5. Vitamin E and Beta Carotene Composition in Four Different Vegetable Oils

    Directory of Open Access Journals (Sweden)

    Ab. G.M. Top


    Full Text Available Problem statement: Some vegetable oils contains natural antioxidants such as beta carotene and vitamin E namely tocopherol and tocotrienol. Different vegetable oils contained different amount of vitamin E and β-carotene. Approach: Study was carried out to investigate the natural antioxidants (vitamin E and beta carotene composition in four different vegetable oils [Red Palm Olein (RPO, palm plein (PO, Corn Oil (CO and Coconut Oil (COC]. Results: The results showed that RPO contained the highest amount of vitamin E and β-carotene compared to the other three types of vegetable oils studied. Conclusion: The RPO can be considered as a good source of natural antioxidant (tocopherol, tocotrienol and β-carotene.

  6. Neutrino mass hierarchy and {theta}{sub 13} with a magic baseline beta-beam experiment

    Energy Technology Data Exchange (ETDEWEB)

    Agarwalla, Sanjib Kumar [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211019 (India) and Department of Physics, University of Calcutta, 92 Acharya Prafulla Chandra Road, Kolkata 700009 (India)]. E-mail:; Choubey, Sandhya [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211019 (India)]. E-mail:; Raychaudhuri, Amitava [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211019 (India) and Department of Physics, University of Calcutta, 92 Acharya Prafulla Chandra Road, Kolkata 700009 (India)]. E-mail:


    We underscore the physics advantage of an experiment where neutrinos produced in a beta-beam facility at CERN are observed in a large magnetized iron calorimeter (ICAL) at the India-based Neutrino Observatory (INO). The CERN-INO distance is close to the so-called 'magic' baseline which helps evade some of the parameter degeneracies and allows for a better measurement of the neutrino mass hierarchy and {theta}{sub 13}. We expound the possibility of using radioactive {sup 8}B and {sup 8}Li as the source isotopes for the {nu}{sub e} and {nu}-bar{sub e} beta-beam, respectively, and show that very good sensitivity to both the mass hierarchy and {theta}{sub 13} is possible with a boost {gamma} in the 250-500 ballpark.

  7. A prototype low-background multiwire proportional chamber for measuring alphas and low-energy betas

    CERN Document Server

    Ahmed, Z; Bunker, R; Golwala, S R; Grant, D R; Kos, M; Nelson, R H; Rider, A; Schnee, R W; Sotolongo, D; Wang, B; Zahn, A


    A prototype low-background multiwire proportional chamber (MWPC) was developed to demonstrate the feasibility of constructing a radiopure MWPC to assay materials for alpha- and beta-emitting surface contaminants for future rare-event-search experiments, as well as other scientific fields. We discuss the design features and assembly techniques used to achieve the energy and position resolution for for efficient rejection of both intrinsic and external backgrounds. Results from a test setup using a 5.89\\,keV x-ray source indicate excellent operational stability and a near-ideal energy resolution of 15.8% FWHM. This detector technology promises significant advances in both alpha and low-energy (<200 keV) beta screening.

  8. Measurement of parameters in Indus-2 synchrotron radiation source. (United States)

    Ghodke, A D; Husain, Riyasat; Kumar, Pradeep; Yadav, Surendra; Puntambekar, T A


    The paper presents the measurement of optics parameters in Indus-2 synchrotron radiation source, which include betatron tune, beta function, dispersion function, natural chromaticity, corrected chromaticity, central RF frequency, momentum compaction factor, and linear betatron coupling. Two methods were used for beta function measurement; a conventional quadrupole scan method and a method using the fitting of the orbit response matrix. A robust Levenberg-Marquardt algorithm was used for nonlinear least square fitting of the orbit response matrix. In this paper, detailed methods for the parameter measurements are described. The measured results are discussed and compared with the theoretical values obtained using accelerator simulation code Accelerator Toolbox in MATLAB.

  9. Beta activity in the premotor cortex is increased during stabilized as compared to normal walking

    Directory of Open Access Journals (Sweden)

    Sjoerd M. Bruijn


    Full Text Available Walking on two legs is inherently unstable. Still, we humans perform remarkable well at it, mostly without falling. To gain more understanding of the role of the brain in controlling gait stability we measured brain activity using electro-encephalography (EEG during stabilized and normal walking.Subjects walked on a treadmill in two conditions, each lasting 10 minutes; normal, and while being laterally stabilized by elastic cords. Kinematics of trunk and feet, electro-myography (EMG of neck muscles, as well as 64-channel EEG were recorded. To assess gait stability the local divergence exponent, step width, and trunk range of motion were calculated from the kinematic data. We used independent component analysis to remove movement, EMG, and eyeblink artifacts from the EEG, after which dynamic imaging of coherent sources beamformers were determined to identify cortical sources that showed a significant difference between conditions. Stabilized walking led to a significant increase in gait stability, i.e. lower local divergence exponents. Beamforming analysis of the beta band activity revealed significant sources in bilateral pre-motor cortices. Projection of sensor data on these sources showed a significant difference only in the left premotor area, with higher beta power during stabilized walking, specifically around push-off, although only significant around contralateral push-off. It appears that even during steady gait the cortex is involved in the control of stability.

  10. Characteristic X-rays induced by electrons and positrons from {beta}-emitting radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Chesta, M.A.; Mainardi, R.T. [Facultad de Matematica, Astronomia y Fisica, Universidad Nacional de Cordoba, Ciudad Universitaria, 5010 Cordoba (Argentina); Plivelic, T.S. [Consejo de Investigaciones Cientificas y Tecnicas (CONICET), 1033 Buenos Aires (Argentina)


    We have investigated the use of energetic electrons and positrons from low intensity {sup 90}Sr and {sup 22}Na radioactive sources respectively to produce characteristic radiation and compare the emission efficiencies of each kind of particle. A new proposed experimental set-up for radioisotope-excited X-ray fluorescence analysis is of the transparent source type and provides at least a ten-time increase in the intensity of characteristic X-rays emitted by the sample as compared to a standard radioactive source arrangement. Theoretically derived expressions for {beta}-particle penetration, transport and emission processes in a sample are presented, and experimental results of absolute characteristic X-ray yields induced by electrons and positrons from 31 pure chemical elements, from titanium to lead, have been included. The advantages of energetic {beta}-particles in comparison with other radiation sources are also discussed, in fact, a remarkable feature observed being that radiation yield changes by less than an order of magnitude across the whole range of the target atomic numbers herein considered. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  11. Climate, history and neutrality as drivers of mammal beta diversity in Europe: insights from multiscale deconstruction. (United States)

    Svenning, Jens-Christian; Fløjgaard, Camilla; Baselga, Andrés


    1. Environmental sorting, historical factors and neutral dynamics may all drive beta diversity (change in species composition across space), but their relative importance remains unresolved. In the case of European mammals, key potential drivers of large-scale beta diversity include current climate, neutral dynamics and two historical factors: Pleistocene glaciations and peninsular dynamics (immigration from extra-regional eastern faunal source areas and inter-linked relictual survival and evolutionary differentiation in isolated areas). 2. We assessed the relative importance of these drivers using a novel analytical framework to deconstruct beta diversity of non-volant mammals in Europe (138 species) into its turnover (change in species composition because of species replacements) and nestedness components (change in species composition because of species richness differences) at continental and regional (250,000 km(2) ) scales. 3. We found continental-scale mammal beta diversity to be mainly caused by spatial turnover (99·9%), with only a small contribution (0·1%) from nestedness. 4. Current climate emerged as an important driver of beta diversity, given the strong continental-scale turnover, particularly in north-south direction, i.e., in line with the latitudinal climate gradient, and, more directly, the strong correlation of climate with spatial turnover at both continental and regional scales. 5. However, there was also evidence for the importance of non-climatic drivers. Notably, the compositional variation purely accounted for by space was greater than that purely accounted for by environment for both the turnover and the nestedness component of beta diversity. Furthermore, the strong longitudinal turnover within Southern Europe is in accordance with the region's long-term climatic stability having allowed multiple refugia and local evolutionary diversification. As expected from peninsular dynamics, there was increasing dissimilarity with

  12. The effects of beta-carotene and vitamin E on erythrocytes lipid peroxidation in beta-thalassemia patients

    Directory of Open Access Journals (Sweden)

    Soleiman Mahjoub


    Full Text Available BACKGROUND: Thalassemia is the most common hereditary disease in the world. Thalassemic erythrocytes are exposed to higher oxidative stress and lipid peroxidation. The aim of this study was to investigate the effects of beta-carotene and vitamin E on erythrocytes lipid peroxidation in beta-thalassemia patients.
    METHODS: A prospective double-blind, placebo-controlled study of the effect of beta-carotene and vitamin E on lipid peroxidation in erythrocytes membranes was performed on 120 beta-thalassemia major patients in four groups. The patients were supplemented for 4 weeks as follows: group 1 with beta-carotene (13 mg/day, group 2 with vitamin E (550 mg/day, group 3 with beta-carotene plus vitamin E and group 4 with placebo. We prepared all capsules for 4 roups in the same shape and color. Measurements of serum beta-carotene and vitamin E were performed by high performance
    liquid chromatography. After preparation of ghost cells from blood specimens, malondialdehyde (MDA was determined as index of lipid peroxidation in erythrocytes membranes before and after treatment. RESULTS: The levels of serum beta-carotene and vitamin E were significantly lower and MDA concentrations in erythrocytes membranes were significantly higher in beta-thalassemia patients compared to controls (P<0.001. In groups that treated with vitamin supplements for 4-weeks, lipid peroxidation rates were significantly reduced after treatment (P<0.001, but in placebo group there was not significant difference (P>0.05.
    CONCLUSIONS: Our findings provide evidence that an oral treatment with beta-carotene and vitamin E can significantly reduce lipid peroxidation of erythrocytes membranes and could be useful in management of beta-thalassemia major patients. KEYWORDS: Beta-thalassemia major, beta-carotene, vitamin E, malondialdehyde, lipid peroxidation.

  13. Role of beta-adrenoceptors in memory consolidation: beta3-adrenoceptors act on glucose uptake and beta2-adrenoceptors on glycogenolysis. (United States)

    Gibbs, Marie E; Hutchinson, Dana S; Summers, Roger J


    Noradrenaline, acting via beta(2)- and beta(3)-adrenoceptors (AR), enhances memory formation in single trial-discriminated avoidance learning in day-old chicks by mechanisms involving changes in metabolism of glucose and/or glycogen. Earlier studies of memory consolidation in chicks implicated beta(3)- rather than beta(2)-ARs in enhancement of memory consolidation by glucose, but did not elucidate whether stimulation of glucose uptake or of glycolysis was responsible. This study examines the role of glucose transport in memory formation using central injection of the nonselective facilitative glucose transporter (GLUT) inhibitor cytochalasin B, the endothelial/astrocytic GLUT-1 inhibitor phloretin and the Na(+)/energy-dependent endothelial glucose transporter (SGLT) inhibitor phlorizin. Cytochalasin B inhibited memory when injected into the mesopallium (avian cortex) either close to or between 25 and 45 min after training, whereas phloretin and phlorizin only inhibited memory at 30 min. This suggested that astrocytic/endothelial (GLUT-1) transport is critical at the time of consolidation, whereas a different transporter, probably the neuronal glucose transporter (GLUT-3), is important at the time of training. Inhibition of glucose transport by cytochalasin B, phloretin, or phlorizin also interfered with beta(3)-AR-mediated memory enhancement 20 min posttraining, whereas inhibition of glycogenolysis interfered with beta(2)-AR agonist enhancement of memory. We conclude that in astrocytes (1) activities of both GLUT-1 and SGLT are essential for memory consolidation 30 min posttraining; (2) neuronal GLUT-3 is essential at the time of training; and (3) beta(2)- and beta(3)-ARs consolidate memory by different mechanisms; beta(3)-ARs stimulate central glucose transport, whereas beta(2)-ARs stimulate central glycogenolysis.

  14. Microbial degradation of poly-beta-hydroxyalkanoates. (United States)

    Mas-Castellà, J; Lafuente, R; Urmeneta, J; Goodwin, S; Guerrero, R


    The search for new materials that are not hazardous to the environment has become a major issue in our society, engaged as it is in the attainment of sustainable development. Poly-beta-hydroxyalkanoates (PHA), produced exclusively by prokaryotes, can be used as thermoplastics and are fully biodegradable and innocuous to the environment. Biodegradability testing has quantified the capacity of microorganisms to degrade such new chemical compounds, particularly polyhydroxyalkanoates. Standardized tests may also discover new microorganisms and environmental conditions that accelerate biodegradation. We evaluate various techniques used to assess the biodegradability of PHA, and which may also be applied to test other kinds of polymers.

  15. Intracranial Extramedullary Hematopoiesis in Beta-Thalassemia

    Energy Technology Data Exchange (ETDEWEB)

    Karki, Bivek; Xu, Yi Kai; Wu, Yuan Kui [Nan fang Hospital, Southern Medical University, Guangzhou (China); Tamrakar, Karuna [Zhujiang Hospital, Southern Medical University, Guangzhou (China)


    Extramedullary hematopoiesis (EMH) represents tumor-like proliferation of hemopoietic tissue which complicates chronic hemoglobinopathy. Intracranial EMH is an extremely rare occurrence. Magnetic resonance imaging (MRI) offers a precise diagnosis. It is essential to distinguish EMH from other extradural central nervous system tumors, because treatment and prognosis are totally different. Herein, we report the imaging findings of beta-thalassemia in a 13-year-old boy complaining of weakness of left side of the body and gait disturbance; CT and MRI revealed an extradural mass in the right temporoparietal region.

  16. Perioperative Beta Blockade - A Case Report

    Directory of Open Access Journals (Sweden)

    Sunitha K. Zachariah


    Full Text Available Continuation of antihypertensives preoperatively and their influence on intraoperative hemodynamics is a big concern among anesthesiologists. The Peri Operative Ischaemia Study Evaluation (POISE trial showed a significant reduction of myocardial infarction, need for coronary revascularization and the incidence of atrial fibrillation with metoprolol started 2-4 hours prior to surgery but a significant increase in total mortality and clinically significant hypotension and bradycardia. This is a case report of intraoperative severe bradycardia in a young patient on recently started beta blocker.

  17. Imaging the Beta-cell mass: why and how

    DEFF Research Database (Denmark)

    Saudek, Frantisek; Brogren, Carl-Henrik; Manohar, Srirang


    of the native beta-cell mass is still limited to autopsy studies. Endeavors to find a biological structure specific for beta-cells led to the discovery of potential candidates that have been tested for noninvasive imaging. Among them are the ligand to the vesicular monoamine transporter type 2 (VMAT-2), which......Diabetes is a disorder characterized by beta-cell loss or exhaustion and insulin deficiency. At present, knowledge is lacking on the underlying causes and for the therapeutic recovery of the beta-cell mass. A better understanding of diabetes pathogenesis could be obtained through exact monitoring...... of the fate of beta-cells under disease and therapy conditions. This could pave the way for a new era of intervention by islet replacement and regeneration regimens. Monitoring the beta-cell mass requires a reliable method for noninvasive in vivo imaging. Such a method is not available at present due...

  18. Studies on the metabolism of beta-hydroxy- aspartic acid

    Directory of Open Access Journals (Sweden)



    Full Text Available The content of beta-hydroxyaspartic acid was measured in the urine of man and several species of animals. The configuration of urinary beta-hydroxyaspartic acid was deduced to be L-erythro in form by chromatographic comparisons with authentic samples. An increased excretion of urinary beta-hydroxyaspartic acid was observed in cats when serine or thiamine was administered with glycine. Glycine-1-14C administered to rats was incorporated into the urinary beta-hydroxyaspartic acid. The formation of beta-hydroxyaspartic acid in pig-liver homogenate increased in the presence of glutamate and thiamine pyrophosphate. These results were discussed in relation to the author's working hypothesis on the biosynthesis of beta-hydroxyaspartic acid.

  19. Fracture risk in perimenopausal women treated with beta-blockers

    DEFF Research Database (Denmark)

    Rejnmark, Lars; Vestergaard, Peter; Kassem, Moustapha


    beta2-Adrenergic receptors have been identified on human osteoblastic and osteoclastic cells, raising the question of a sympathetic regulation of bone metabolism. We investigated effects of treatment with beta-adrenergic receptor antagonists (beta-blockers) on bone turnover, bone mineral density...... (BMD), and fracture risk. Within the Danish Osteoporosis Prevention Study (DOPS) a population based, comprehensive cohort study of 2016 perimenopausal women, associations between treatment with beta-blockers and bone turnover and BMD were assessed in a cross-sectional design at the start of study....... Moreover, in a nested case-control design, fracture risk during the subsequent 5 years was assessed in relation to treatment with beta-blockers at baseline. Multiple regression- and logistic regression-analyses were performed. Treatment with beta-blockers was associated with a threefold increased fracture...

  20. Dopaminergic and beta-adrenergic effects on gastric antral motility

    DEFF Research Database (Denmark)

    Bech, K; Hovendal, C P; Gottrup, F


    of bethanechol or pentagastrin inducing motor activity patterns as in the phase III of the MMC and the digestive state respectively. The stimulated antral motility was dose-dependently inhibited by dopamine. The effect was significantly blocked by specifically acting dopaminergic blockers, while alpha- and beta......-adrenergic blockers were without any significant effects. Dose-response experiments with bethanechol and dopamine showed inhibition of a non-competitive type. Isoprenaline was used alone and in conjunction with selective blockade of beta 1- and beta 2-receptors during infusion of bethanechol which induces a pattern...... similar to phase III in the migrating myoelectric complex. The stimulated antral motility was dose-dependently inhibited by isoprenaline. The effect could be significantly blocked by propranolol (beta 1 + beta 2-adrenoceptor blocker) and by using in conjunction the beta 1-adrenoceptor blocker practolol...

  1. Threonine 788 in integrin subunit beta1 regulates integrin activation

    DEFF Research Database (Denmark)

    Nilsson, Stina; Kaniowska, Dorota; Brakebusch, Cord


    was identified as a site with major influence on integrin function. The mutation to A788 strongly reduced beta1-dependent cell attachment and exposure of the extracellular 9EG7 epitope, whereas replacement of T789 with alanine did not interfere with the ligand-binding ability. Talin has been shown to mediate......In the present study, the functional role of suggested phosphorylation of the conserved threonines in the cytoplasmic domain of integrin subunit beta1 was investigated. Mutants mimicking phosphorylated and unphosphorylated forms of beta1 were expressed in beta1 deficient GD25 cells. T788 in beta1...... integrin activation, but the talin head domain bound equally well to the wild-type beta1 and the mutants indicating that the T788A mutation caused defect integrin activation by another mechanism. The phosphorylation-mimicking mutation T788D was fully active in promoting cell adhesion. GD25 cells expressing...

  2. 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.


    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.

  3. Antibodies against Pseudomonas aeruginosa chromosomal beta-lactamase inpatients with cystic fibrosis are markers of the development of resistance of P. aeruginosa to beta-lactams

    DEFF Research Database (Denmark)

    Ciofu, O; Giwercman, B; Walter-Rasmussen, J


    Chromosomal beta-lactamase production is considered to be the most important resistance mechanism of Pseudomonas aeruginosa against beta-lactams. Recently we have detected serum and sputum antibodies against P. aeruginosa chromosomal beta-lactamase (a beta ab), using immunoblotting techniques...... infection and was significantly higher (P beta-lactam courses. A 14 fold increase in a beta ab...... levels occurred during the 14 year period covered by the longitudinal study. The results of this study show that a beta ab to P. aeruginosa is a specific marker for resistance development of P. aeruginosa to beta-lactams....

  4. Secretion of beta-human chorionic gonadotropin by non-small cell lung cancer: a case report

    Directory of Open Access Journals (Sweden)

    Varma Seema


    Full Text Available Abstract Introduction We describe a case of non-small cell lung cancer that was found to stain positive for beta-human chorionic gonadotropin on immunohistochemistry. Only a few case reports have described lung cancers that secrete beta-human chorionic gonadotropin. Case presentation A 68-year-old Caucasian man presented with symptoms of weakness, fatigue and weight loss for the past two months. On examination, he was found to have generalized lymphadenopathy, and radiologic workup revealed numerous metastases in the lungs, liver and kidneys. Biopsy of the supraclavicular lymph node revealed metastatic large cell lung cancer with beta-human chorionic gonadotropin hormone positivity. The serum beta-human chorionic gonadotropin level was 11,286 mIU/ml (upper limit of normal, 0.5 mIU/ml in non-pregnant females. He was diagnosed with stage 4 lung non-small cell lung cancer. The patient refused chemotherapy. He was discharged home with hospice care. Conclusion The markedly elevated serum values of beta-human chorionic gonadotropin initially prompted the medical team to investigate germinal tumors. In the presence of a negative testicular ultrasound, workup was performed to find an extratesticular source of the tumor. Finally, the diagnosis was made with a tissue biopsy. This case illustrates that atypical markers can be seen in many cancers, emphasizing the role of immunohistochemistry and tissue biopsy in establishing the diagnosis.

  5. Simultaneous biological removal of endosulfan (alpha+beta) and nitrates from drinking waters using wheat straw as substrate. (United States)

    Aslan, Sükrü; Türkman, Ayşen


    Nitrate and endosulfan (alpha+beta) removal was studied in an upflow biological denitrification reactor packed with wheat straw as carbon source and support particles for microorganisms. While almost complete nitrate elimination and between 65% and 70% endosulfan (alpha+beta) elimination occurred when the temperature was higher than 20 degrees C; below that value, nitrate removal efficiency decreased to about 10%. Nitrate, dissolved organic carbon (DOC), and endosulfan (alpha+beta) removal efficiencies decreased considerably at 1500 microg/l endosulfan concentration in the batch experiments. Although a high removal efficiency was observed for endosulfan (alpha+beta) and nitrate in the biological denitrification continuous reactor, the effluent water could not be used for drinking purpose because of the unacceptable levels of endosulfan (alpha+beta), colour and dissolved organic content. During the continuous study, 23.4% of the initial weight of wheat straw was lost and 24 g was consumed per gram of nitrogen removed. The results of the continuous study showed that 21.3% of the endosulfan removal was achieved by adsorption onto the wheat straw and 68.2% of the endosulfan removal occurred by biological activity and the remaining portion was detected in the effluent water.

  6. Factors Influencing Beta-Thalassemia Awareness in Western India


    Ashwin P Patel; Prakash H Parmar; Rupesh B Patel; Nikhil M Trivedi; Nileshkumar A Bhartiya


    "Context: Beta-thalassemia is highly prevalent in western India. Our organization runs a screening and prevention program to create awareness and reduce the incidence of homozygous beta-thalassemia cases. Aims: The study was designed to evaluate factors influencing awareness about Beta-thalassemia. Methodology: This cross sectional survey was conducted at six colleges, two medical clinics, and a thalassemia transfusion centre. It involved 398 adults ( and #8805;18 years).The survey form...

  7. New exotics in the double beta decay contributions zoo

    CERN Document Server

    Klapdor-Kleingrothaus, H V; Sarkar, U


    We discuss the potential of neutrinoless double beta decay for testingLorentz invariance and the weak equivalence principle as well as contributionsfrom dilaton exchange gravity in the neutrino sector. While neutrinooscillation bounds constrain the region of large mixing of the weak andgravitational eigenstates, we obtain new constraints on violations of Lorentzinvariance and the equivalence principle from neutrinoless double beta decay,applying even in the case of no mixing. Double beta decay thus probes a totallyunconstrained region in the parameter space.

  8. Proceedings of the Department of Energy workshop on beta measurements

    Energy Technology Data Exchange (ETDEWEB)

    Swinth, K.L.; Vallario, E.J.


    Participants discussed current practices, efforts to upgrade the quality of beta measurements, and initiatives necessary to improve the measurement and control of beta doses. This proceedings includes papers presented at the workshop, transcripts of panel and open discussions, and documentation of question and answer sessions. The information exchange resulting from this meeting is expected to provide a clearer focus on the problems of beta measurements.

  9. Influence of. beta. -phase unhomogeneity on titanium martensite structure

    Energy Technology Data Exchange (ETDEWEB)

    Gridnev, V.N.; Ivasishin, O.M.; Markovskij, P.E.; Oshkaderov, S.P.; Svechnikov, V.L. (AN Ukrainskoj SSR, Kiev. Inst. Metallofiziki)

    Martensite structure is studied, formed by the hardening of unhomogeneous ..beta..-solid solution, its concentration unhomogeneity being formed under accelerated heating while hardening. It is established that changes in morphology and crystal geometry of martensite are observed with hardening temperature increasing. The concentration unhomogeneity of ..beta..-phase may lead to the simultaneous existence of various types of martensite together with the increased quantity of the residual ..beta..-phase.

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

    DEFF Research Database (Denmark)

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


    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 ...

  11. Shape-coexistence and shape-evolution studies for bismuth isotopes by insource laser spectroscopy and $\\beta$-delayed fission in $^{188}$Bi

    CERN Multimedia

    The proposal aims at the two main goals: \\\\ \\\\1) the studies of shape-coexistence and shape-evolution phenomena in the long chain of bismuth isotopes (Z=83) by in-source laser spectroscopy measurements of isotopic shifts (IS) and hyperfine structures (hfs), and \\\\ 2) $\\beta$-delayed fission ($\\beta$DF) of two isomeric states in $^{188}$Bi. \\\\ \\\\Isomer-selective $\\beta$DF studies for $^{188m1, 188m2}$Bi isomers will enable us for the first time to investigate the spin-dependence of the $\\beta$DF process and to check theoretical predictions of asymmetrical fission fragment mass-distribution in this region of nuclei. The measurements will be performed with the well-proven Windmill and MR-TOF MS/Penning Trap techniques.

  12. Noncovalent Interaction Energies in Covalent Complexes: TEM-1 beta-Lactamase and beta-Lactams

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaojun; Minasov, George; Shoichet, Brian K. (NWU)


    The class A {beta}-lactamase TEM-1 is a key bacterial resistance enzyme against {beta}-lactam antibiotics, but little is known about the energetic bases for complementarity between TEM-1 and its inhibitors. Most inhibitors form a covalent adduct with the catalytic Ser70, making the measurement of equilibriumconstants, and hence interaction energies, technically difficult. This study evaluates noncovalent interactions withincovalent complexes by examining the differential stability of TEM-1 and its inhibitor adducts. The thermal denaturation of TEM-1 follows a two-state, reversible model with a melting temperature (T{sub m}) of 51.6 C and a van't Hoff enthalpy of unfolding ({Delta}H{sub VH}) of 146.2 kcal/mol at pH 7.0. The stability of the enzyme changes on forming an inhibitor adduct. As expected, some inhibitors stabilize TEM-1; transition-state analogues increase the T{sub m} by up to 3.7 C(1.7 kcal/mol). Surprisingly, all {beta}-lactam covalent acyl-enzyme complexes tested destabilize TEM-1 significantly relative to the apoenzyme. For instance, the clinically used inhibitor clavulanic acid and the {beta}-lactamase-resistant {beta}-lactams moxalactam and imipenem destabilize TEM-1 by over 2.6 C (1.2 kcal/mol) in their covalent adducts. Based on the structure of the TEM-1/imipenem complex (Maveyraud et al., J Am Chem Soc 1998;120:9748-52), destabilization by moxalactam and imipenem is thought to be caused by a steric clash between the side-chain of Asn132 and the 6(7)-{alpha} group of these {beta}-lactams. To test this hypothesis, the mutant enzyme N132A was made. In contrast with wild-type, the covalent complexes between N132A and both imipenem and moxalactam stabilize the enzyme, consistent with the hypothesis. To investigate the structural bases of this dramatic change instability, the structure of N132A/imipenem was determined by X-ray crystallography. In the complex with N132A, imipenemadopts a very different conformation from that observed in the wild

  13. Latency and activation in the control of TGF-beta (United States)

    Barcellos-Hoff, M. H.; Chatterjee, A. (Principal Investigator)


    The biological activity of the transforming growth factor-beta's (TGF-beta)3 is tightly controlled by their persistence in the extracellular compartment as latent complexes. Each of the three mammalian isoform genes encodes a product that is cleaved intracellularly to form two polypeptides, each of which dimerizes. Mature TGF-beta, a 24 kD homodimer, is noncovalently associated with the 80 kD latency-associated peptide (LAP). LAP is a fundamental component of TGF-beta that is required for its efficient secretion, prevents it from binding to ubiquitous cell surface receptors, and maintains its availability in a large extracellular reservoir that is readily accessed by activation. This latent TGF-beta complex (LTGF-beta) is secreted by all cells and is abundant both in circulating forms and bound to the extracellular matrix. Activation describes the collective events leading to the release of TGF-beta. Despite the importance of TGF-beta regulation of growth and differentiation in physiological and malignant tissue processes, remarkably little is known about the mechanisms of activation in situ. Recent studies of irradiated mammary gland reveal certain features of TGF-beta 1 activation that may shed light on its regulation and potential roles in the normal and neoplastic mammary gland.

  14. Ubuntu 6.10 Edgy Beta 1发布

    Institute of Scientific and Technical Information of China (English)


    近日,Ubuntu项目发布Ubuntu 6.10 Edgy Eft Beta 1版本,Edgy Eft Beta 1包含新的2.6.17版本内核、Xorg 7.1、GNOME 2.16正式版、新的Firefox浏览器Firefox2.0 Beta2、OpenOffice.org2.0.4RC2版本、聊天软件Gaim的新版本2.0 Beta3.1和新的init系统。

  15. Management of pregnancy in a patient with beta thalassaemia major. (United States)

    Butwick, A; Findley, I; Wonke, B


    beta thalassaemia is one of the world's most wide-spread monogenetic disorders. Advances in the management of beta thalassaemia major by extensive blood transfusions and chelation therapy have improved survival of patients into adult life. Due to the prolonged life expectancy and improvements in quality of life, pregnancy has now become an important issue for patients and clinicians. We report a case of a pregnant patient with beta thalassaemia major who underwent a successful caesarean section under spinal anaesthesia. The multidisciplinary approach to management of beta thalassaemia major and pregnancy is discussed.

  16. A new ultrasensitive bioluminogenic enzyme substrate for beta-galactosidase. (United States)

    Geiger, R; Schneider, E; Wallenfels, K; Miska, W


    A derivative of D-luciferin, D-luciferin-O-beta-galactoside, was synthesized and used as highly sensitive substrate for beta-galactosidase. The substrate was physicochemically characterized. Enzymatic cleavage of the new compound by beta-galactosidase was demonstrated and kinetic constants Km, Vmax, kcat and kcat/Km have been determined. The compound has been proved to be a highly sensitive substrate for beta-galactosidase, permitting a limit of detection of 3.7 x 10(-19) mol of enzyme per assay.

  17. Interaction between {beta}-Lapachone and Ionizing Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Eun Kyung; Song, Si Yeol; Shin, Seong Soo; Lee, Sang Wook; Ahn, Seung Do; Kim, Jong Hoon [College of Medicine, University of Ulsan, Seoul (Korea, Republic of); Park, Heon Joo [College of Medicine, Inha University, Incheon (Korea, Republic of); Song, Chang Won [University of Minnesota Medical School, Minneapolis (United States)


    {beta}-Lapachone (3,4-dihydro-2,2-dimethyl-2Hnaphtho[ 1,2-b]pyran-5,6-dione)({beta}-lap) was originally isolated from the bark of the Lapacho tree growing in South America (1). This drug has attracted considerable interest in recent years because of its potent cytotoxicity against various cancer cell lines through a mechanism that works independent of the cell cycle of p53 status. Interestingly, {beta}-lap has been reported to react synergistically with Taxol, mitomycin C, genistein, and ionizing radiation (IR) (2-3) in vitro against cultured cancer cells. It has also been reported that {beta}-lap inhibits the repair of potentially lethal radiation damage by converting repairable single-stranded DNA breaks into repair-resistant, double-stranded DNA breaks. Thus {beta}- lap has been thought to act as a radiation sensitizer by inhibiting DNA damage repair. In the present study, we observed that IR sensitizes cancer cells to {beta}-lap. It thus appeared that the synergistic interaction of IR and {beta}-lap in killing cancer cells was due to an increase in cellular susceptibility to {beta}-lap, probably in addition to {beta}-lap. induced radiosensitization.

  18. Aluminium, beta-amyloid and non-enzymatic glycosylation. (United States)

    Exley, C; Schley, L; Murray, S; Hackney, C M; Birchall, J D


    The non-enzymatic glycosylation of beta-amyloid is implicated in the aetiology of Alzheimer's disease. However, controversy surrounds the nature of any involvement and a potential mechanism has not been fully elucidated. We present evidence of an aluminium-induced aggregation of the A beta P(25-35) peptide and speculate that the mechanism of formation of our ordered beta-amyloid aggregates might involve non-enzymatic glycosylation and/or site-specific crosslinking of beta-amyloid fibrils by atomic aluminium.

  19. Beta 2-Microglobulin clearance as measured by radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Woo, J.; Floyd, M.; Longley, M.A.; Cannon, D.C.


    We describe a radioimmunoassay for beta 2-microglobulin (beta 2 mu) in serum and urine. We incubated aliquots of diluted samples at room temperature for 1 h with /sup 125/I-labeled beta 2 mu and a rabbit antiserum monospecific for human beta 2 mu, and separated the phases by the double-antibody technique. The logit-log transformed dose-response curve was linear in the range 2 to 64 ng, equivalent to 0.5 to 16 mg/L of serum and 0.5 to 320 mg/L of urine. Assay sensitivity was 2.4 ng of beta 2 mu. Validation studies included tests of precision, accuracy, antibody specificity, and parallelism of the dose-response curves for standard and unknown. In a study of 25 normal individuals, serum and urine beta 2 mu ranged from 1.1 to 2.3 mg/L and 40 to 360 micrograms/24 h; the clearance of beta 2 mu was 8 to 130 microL/min. In 21 renal allograft recipients tested one to five weeks after transplantation, serum and urine beta 2 mu ranged from 3.9 to 15.6 mg/L and 7.2 to 611 mg/24 h; beta 2 mu clearance was 0.60 to 33.3 mL/min. Values for both serum and urine correlated well with severity of allograft rejection.

  20. 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


    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 role of beta-lactamase in the pharmacokinetics (PK) and pharmacodynamics (PD) of ceftazidime and imipenem on P. aeruginosa biofilms. P. aeruginosa PAO1 and its corresponding beta-lactamase-overproducing mutant, PA Delta DDh2Dh3, were used in this study. Biofilms of these two strains in flow chambers...... 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...

  1. Design, synthesis, and evaluation of 2 beta-alkenyl penam sulfone acids as inhibitors of beta-lactamases. (United States)

    Richter, H G; Angehrn, P; Hubschwerlen, C; Kania, M; Page, M G; Specklin, J L; Winkler, F K


    A general method for synthesis of 2 beta-alkenyl penam sulfones has been developed. The new compounds inhibited most of the common types of beta-lactamase. The level of activity depended very strongly on the nature of the substituent in the 2 beta-alkenyl group. The inhibited species formed with the beta-lactamase from Citrobacter freundii 1205 was sufficiently stable for X-ray crystallographic studies. These, together with UV absorption spectroscopy and studies of chemical degradation, suggested a novel reaction mechanism for the new inhibitors that might account for their broad spectrum of action. The (Z)-2 beta-acrylonitrile penam sulfone Ro 48-1220 was the most active inhibitor from this class of compound. The inhibitor enhanced the action of, for example, ceftriaxone against a broad selection of organisms producing beta-lactamases. The organisms included strains of Enterobacteriaceae that produce cephalosporinases, which is an exceptional activity for penam sulfones.

  2. Vaccinia virus recombinants expressing an 11-kilodalton beta-galactosidase fusion protein incorporate active beta-galactosidase in virus particles. (United States)

    Huang, C; Samsonoff, W A; Grzelecki, A


    Recombinant plasmids in which vaccinia virus transcriptional regulatory sequences were fused to the Escherichia coli lacZ gene were constructed for insertion of the lacZ gene into the vaccinia virus genome. beta-Galactosidase (beta-gal) was found in some purified recombinant vaccinia virions. By enzyme activity, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and microscopic techniques, the evidence suggested that beta-gal accounted for 5% of the total protein in the virion. These recombinant viruses were constructed so that a portion of the coding sequences of a late vaccinia virus structural polypeptide was fused to the amino terminus of beta-gal to produce the fusion protein. Removal of the coding sequences resulted in the complete loss of beta-gal activity. This demonstrated that a vaccinia virus DNA segment from a late structural gene is responsible for the incorporation of beta-gal into the virion.

  3. Intravenous desensitization to beta-lactam antibiotics. (United States)

    Borish, L; Tamir, R; Rosenwasser, L J


    Patients allergic to penicillin (PCN) often require treatment with beta-lactam antibiotics for life-threatening bacterial infections. In this article, we review our experience with rapid intravenous desensitization for patients who gave a history of PCN allergy and who had hypersensitivity demonstrated by skin tests. Skin testing was performed with both prick and intradermal techniques and with the recommended antibiotic as well as PCN G, penicilloyl polylysine, and a minor determinant mixture. Patients were transferred to the intensive care unit, and desensitization was performed with a buret technique that required minimal preparation and was easily applied to any antibiotic. Fifteen desensitizations in 12 patients were associated with no immediate reactions. One patient developed a delayed reaction consisting of a pruritic rash and angioedema. A second patient developed a more serious delayed serum sickness-like illness with fever, rash, eosinophilia, abnormal liver function tests, and urinary abnormalities. These reactions did not necessitate stopping the antibiotic, although the latter patient required corticosteroids to suppress his symptoms. Rapid intravenous desensitization is a rapid, safe, and effective technique for patients demonstrating hypersensitivity to beta-lactam antibiotics who require therapy with these medications.

  4. Apoptosis of beta cells in diabetes mellitus. (United States)

    Anuradha, Rachakatla; Saraswati, Mudigonda; Kumar, Kishore G; Rani, Surekha H


    Diabetes mellitus is a multifactorial metabolic disorder characterized by hyperglycemia. Apoptosis in beta cells has been observed in response to diverse stimuli, such as glucose, cytokines, free fatty acids, leptin, and sulfonylureas, leading to the activation of polyol, hexosamine, and diacylglycerol/protein kinase-C (DAG/PKC) pathways that mediate oxidative and nitrosative stress causing the release of different cytokines. Cytokines induce the expression of Fas and tumor necrosis factor-alpha (TNF-α) by activating the transcription factor, nuclear factor-κb, and signal transducer and activator of transcription 1 (STAT-1) in the β cells in the extrinsic pathway of apoptosis. Cytokines produced in beta cells also induce proapoptotic members of the intrinsic pathway of apoptosis. The genetic alterations in apoptosis signaling machinery and the pathogenesis of diabetes include Fas, FasL, Akt, caspases, calpain-10, and phosphatase and tensin homolog (Pten). The other gene products that are involved in diabetes are nitric oxide synthase-2 (NOS2), small ubiquitin-like modifier (SUMO), apolipoprotein CIII (ApoCIII), forkhead box protein O1 (FOXO1), and Kruppel-like zinc finger protein Gli-similar 3 (GLIS3). The gene products having antiapoptotic nature are Bcl-2 and Bcl-XL. Epigenetic mechanisms play an important role in type I and type II diabetes. Further studies on the apoptotic genes and gene products in diabetics may be helpful in pharmacogenomics and individualized treatment along with antioxidants targeting apoptosis in diabetes.

  5. Oscillations in Beta UMi - Observations with SMEI

    CERN Document Server

    Tarrant, N J; Elsworth, Y; Spreckley, S A; Stevens, I R


    Aims: From observations of the K4III star Beta UMi we attempt to determine whether oscillations or any other form of variability is present. Methods: A high-quality photometric time series of approximately 1000 days in length obtained from the SMEI instrument on the Coriolis satellite is analysed. Various statistical tests were performed to determine the significance of features seen in the power density spectrum of the light curve. Results: Two oscillations with frequencies 2.44 and 2.92 microhertz have been identified. We interpret these oscillations as consecutive overtones of an acoustic spectrum, implying a large frequency spacing of 0.48 microhertz. Using derived asteroseismic parameters in combination with known astrophysical parameters, we estimate the mass of Beta UMi to be 1.3 +/- 0.3 solar masses. Peaks of the oscillations in the power density spectrum show width, implying that modes are stochastically excited and damped by convection. The mode lifetime is estimated at 18 +/- 9 days.

  6. Neutrinoless double beta decay search with SNO+

    Directory of Open Access Journals (Sweden)

    Lozza V.


    Full Text Available The SNO+ experiment is the follow up of SNO. The detector is located 2 km underground in the Vale Canada Ltd.’s Creighton Mine near Sudbury, Ontario, Canada. The active volume of the detector consists of 780 tonnes of Linear Alkyl Benzene (LAB in an acrylic vessel of 12 m diameter, surrounded by about 9500 PMTs. The main goal of the SNO+ experiment is the search for neutrinoless double beta decay of 130Te. With an initial loading of 0.3% of natural tellurium (nearly 800 kg of 130Te, it is expected to reach a sensitivity on the effective Majorana neutrino mass of about 100 meV after several years of data taking. Designed as a general purpose neutrino experiment, other exciting physical goals can be explored, like the measurement of reactor neutrino oscillations and geo-neutrinos in a geologically-interesting location, watch of supernova neutrinos and studies of solar neutrinos. A first commissioning phase with water filled detector will start at the end of 2013, while the double beta decay phase will start in 2015.

  7. A background free double beta decay experiment (United States)

    Giomataris, I.


    We present a new detection scheme for rejecting backgrounds in neutrino-less double beta decay experiments. It relies on the detection of Cherenkov light emitted by electrons in the MeV region. The momentum threshold is tuned to reach a good discrimination between background and good events. We consider many detector concepts and a range of target materials. The most promising is the high-pressure 136Xe emitter where the required energy threshold is easily adjusted. Combination of this concept and a high pressure Time Projection Chamber could provide an optimal solution. A simple and low cost effective solution is the use of the Spherical Proportional Counter that provides, using a single read-out channel, two delayed signals from ionization and Cherenkov light. In solid-state double beta decay emitters, because of its higher density, the considered process is out of energy range. An escape will be the fabrication of double decay emitters having lower density by using for instance the aerogel technique. It is surprising that a technology used for particle identification in high-energy physics becomes a powerful tool for rejecting backgrounds in such low-energy experiments.

  8. A background free double beta decay experiment

    CERN Document Server

    Giomataris, Ioannis


    We present a new detection scheme for rejecting backgrounds in neutrino less double beta decay experiments. It relies on the detection of Cherenkov light emitted by electrons in the MeV region. The momentum threshold is tuned to reach a good discrimination between background and good events. We consider many detector concepts and a range of target materials. The most promising is a high-pressure 136Xe emitter for which the required energy threshold is easily adjusted. Combination of this concept and a high pressure Time Projection Chamber could provide an optimal solution. A simple and low cost effective solution is to use the Spherical Proportional Counter that provides two delayed signals from ionization and Cherenkov light. In solid-state double beta decay emitters, because of their higher density, the considered process is out of energy range. An alternative solution could be the development of double decay emitters with lower density by using for instance the aerogel technique. It is surprising that a te...

  9. 1-(beta-D-Erythrofuranosyl)adenosine. (United States)

    Kline, Paul C; Zhao, Hongqiu; Noll, Bruce C; Oliver, Allen G; Serianni, Anthony S


    The title compound, also known as beta-erythroadenosine, C(9)H(11)N(5)O(3), (I), a derivative of beta-adenosine, (II), that lacks the C5' exocyclic hydroxymethyl (-CH(2)OH) substituent, crystallizes from hot ethanol with two independent molecules having different conformations, denoted (IA) and (IB). In (IA), the furanose conformation is (O)T(1)-E(1) (C1'-exo, east), with pseudorotational parameters P and tau(m) of 114.4 and 42 degrees, respectively. In contrast, the P and tau(m) values are 170.1 and 46 degrees, respectively, in (IB), consistent with a (2)E-(2)T(3) (C2'-endo, south) conformation. The N-glycoside conformation is syn (+sc) in (IA) and anti (-ac) in (IB). The crystal structure, determined to a resolution of 2.0 A, of a cocrystal of (I) bound to the enzyme 5'-fluorodeoxyadenosine synthase from Streptomyces cattleya shows the furanose ring in a near-ideal (O)E (east) conformation (P = 90 degrees and tau(m) = 42 degrees) and the base in an anti (-ac) conformation.

  10. Synthesis of electroplated {sup 63}Ni source and betavoltaic battery

    Energy Technology Data Exchange (ETDEWEB)

    Uhm, Young Rang; Yoo, Kwon Mo; Choi, Sang Mu; Kim, Jin Joo; Son, Kwang Jae [Radioisotope Research Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)


    Radioisotope (Nuclear) battery using {sup 63}Ni was prepared as beta cell. The electroplated {sup 63}Ni on Ni foil is fabricated, and beta cell and photovoltaic hybrid battery was designed to use at both day and night in space project. A Ni-plating solution is prepared by dissolving metal particles including {sup 62}Ni and {sup 63}Ni from neutron irradiation of (n,γ). Electroplating solution of a chloride bath consists on nickel ions in HCl, H{sub 3}BO{sub 3}, and KOH. The deposition was carried out at current density of 10 mA cm{sup -2}. The prepared beta source was attached on a PN junction and measured I-V properties. The power output at activity of 0.07 mCi and 0.45 mCi were 0.55 pW and 2.69 nW, respectively.

  11. Room-temperature LINAC structures for the spallation neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Billen, J. H. (James H.); Young, L. M. (Lloyd M.); Kurennoy, S. (Sergey); Crandall, K. R. (Kenneth R.)


    Los Alamos National Laboratory is building room-temperature rf accelerating structures for the Spallation Neutron Source (SNS). These structures, for H{sup -} ions, consist of six 402.5-MHz, 2-MW drift-tube linac (DTL) tanks from 2.5 to 87 MeV followed by four 805-MHz, 4-MW coupled-cavity linac (CCL) modules to 186 MeV. The DTL uses permanent magnet quadrupoles inside the drift tubes arranged in a 6{beta}{lambda} FFODDO lattice with every third drift tube available for diagnostics and steering. The CCL uses a 13{beta}{lambda} FODO electromagnetic quadrupole lattice. Diagnostics and magnets occupy the 2.5{beta}{lambda} spaces between 8-cavity segments. This paper discusses design of the rf cavities and low-power modeling work.

  12. Silencing of beta-carotene hydroxylase increases total carotenoid and beta-carotene levels in potato tubers

    Directory of Open Access Journals (Sweden)

    Pizzichini Daniele


    Full Text Available Abstract Background Beta-carotene is the main dietary precursor of vitamin A. Potato tubers contain low levels of carotenoids, composed mainly of the xanthophylls lutein (in the beta-epsilon branch and violaxanthin (in the beta-beta branch. None of these carotenoids have provitamin A activity. We have previously shown that tuber-specific silencing of the first step in the epsilon-beta branch, LCY-e, redirects metabolic flux towards beta-beta carotenoids, increases total carotenoids up to 2.5-fold and beta-carotene up to 14-fold. Results In this work, we silenced the non-heme beta-carotene hydroxylases CHY1 and CHY2 in the tuber. Real Time RT-PCR measurements confirmed the tuber-specific silencing of both genes . CHY silenced tubers showed more dramatic changes in carotenoid content than LCY-e silenced tubers, with beta-carotene increasing up to 38-fold and total carotenoids up to 4.5-fold. These changes were accompanied by a decrease in the immediate product of beta-carotene hydroxylation, zeaxanthin, but not of the downstream xanthophylls, viola- and neoxanthin. Changes in endogenous gene expression were extensive and partially overlapping with those of LCY-e silenced tubers: CrtISO, LCY-b and ZEP were induced in both cases, indicating that they may respond to the balance between individual carotenoid species. Conclusion Together with epsilon-cyclization of lycopene, beta-carotene hydroxylation is another regulatory step in potato tuber carotenogenesis. The data are consistent with a prevalent role of CHY2, which is highly expressed in tubers, in the control of this step. Combination of different engineering strategies holds good promise for the manipulation of tuber carotenoid content.

  13. Effects of the perfusion of beta-, beta2-, or beta3-adrenergic agonists or epinephrine on in situ adipose tissue lipolysis measured by microdialysis in underfed ewes. (United States)

    Ferlay, A; Charret, C; Galitzky, J; Berlan, M; Chilliard, Y


    The effects of isoproterenol (ISO, a non-selective beta-agonist), terbutaline (TER, a selective beta2-agonist), CL316243 (CL, a selective beta3-agonist), and epinephrine (EPI, beta- and alpha2-agonist) on in situ lipolytic response of s.c. adipose tissue were investigated in vivo, using a microdialysis method to measure glycerol release, in 12 adult nonlactating and ovariectomized, underfed Lacaune ewes. All the adrenergic compounds were perfused for 120 min at 10(-6), 10(-5), and 10(-4) M. They had no lipolytic effect at 10(-6) M. Isoproterenol and EPI at 10(-5) and 10(-4) M enhanced, in the same way, maximal response and area under the concentration curve (AUC) of dialysate glycerol, thus suggesting that involvement of alpha2-adrenoceptors in the control of in situ lipolysis is of minor importance in underfed ewes. Terbutaline had only a slight lipolytic effect at 10(-5) M. This low effect could be due to a lower affinity of TER than of ISO for the beta2-adrenoceptors. The beta3-agonist, CL, had no lipolytic effect whatever the concentration perfused. Further studies are needed to prove the putative presence of beta3-adrenoceptors and their possible role in the ovine adipose tissue.

  14. Endocrine expression of the active form of TGF-beta1 in the TGF-beta1 null mice fails to ameliorate lethal phenotype. (United States)

    Longenecker, Glenn; Thyagarajan, Tamizchelvi; Nagineni, Chandrasekharam N; Flanders, Kathleen C; Factor, Valentina; Miller, Georgina; Ward, Jerrold M; Nalca, Aysegul; Rangnekar, Vivek M; Thorgeirsson, Snorri; Kulkarni, Ashok B


    TGF-beta1 null mice die by 3 to 4 weeks of age due to a severe autoimmune-mediated multifocal inflammation resulting in multi-organ failure. To assess the therapeutic potential of circulating levels of active TGF-beta1, we generated mice with endocrine expression of active TGF-beta1 on a TGF-beta1 null background (TGF-beta1 (-/-/TG)) by crossing TGF-beta1(+/-) mice with transgenic mice (TG) that express recombinant TGF-beta1 specifically in the liver and secrete it in the blood. The TGF-beta1 (-/-/TG) mice exhibit a survival profile similar to the TGF-beta1 (-/-) mice indicating a failure to rescue the lethal phenotype. However, serum TGF-beta1 levels in the TGF-beta1 (-/-/TG) mice were restored to near normal levels with expression in all the tissues, notably in the kidney and spleen. Histopathology showed reduced inflammation in the target tissues, especially in the heart. Interestingly, unlike TGF-beta1 (-/-) mice, the TGF-beta1 (-/-/TG) mice have glomerulonephritis in their kidneys similar to the TG mice. Thus, the phenotype of TGF-beta1 (-/-/TG) animal model indicates the potential role of circulating active-TGF-beta1 in reducing inflammation, but its failure to rescue lethality in TGF-beta1 null mice indicates a critical autocrine role of TGF-beta1.

  15. Molecular analysis of the beta-globin gene cluster in the Niokholo Mandenka population reveals a recent origin of the beta(S) Senegal mutation. (United States)

    Currat, Mathias; Trabuchet, Guy; Rees, David; Perrin, Pascale; Harding, Rosalind M; Clegg, John B; Langaney, André; Excoffier, Laurent


    A large and ethnically well-defined Mandenka sample from eastern Senegal was analyzed for the polymorphism of the beta-globin gene cluster on chromosome 11. Five RFLP sites of the 5' region were investigated in 193 individuals revealing the presence of 10 different haplotypes. The frequency of the sickle-cell anemia causing mutation (beta(S)) in the Mandenka estimated from this sample is 11.7%. This mutation was found strictly associated with the single Senegal haplotype. Approximately 600 bp of the upstream region of the beta-globin gene were sequenced for a subset of 94 chromosomes, showing the presence of four transversions, five transitions, and a composite microsatellite polymorphism. The sequence of 22 beta(S) chromosomes was also identical to the previously defined Senegal haplotype, suggesting that this mutation is very recent. Monte Carlo simulations (allowing for a specific balancing selection model, a logistic growth of the population, and variable initial frequencies of the Senegal haplotype) were used to estimate the age of the beta(S) mutation. Resulting maximum-likelihood estimates are 45-70 generations (1,350-2,100 years) for very different demographic scenarios. Smallest confidence intervals (25-690 generations) are obtained under the hypothesis that the Mandenka population is large (N(e) >5,000) and stationary or that it has undergone a rapid demographic expansion to a current size of >5,000 reproducing individuals, which is quite likely in view of the great diversity found on beta(A) chromosomes.

  16. Micellisation and immunoreactivities of dimeric beta-caseins. (United States)

    Yousefi, Reza; Gaudin, Jean-Charles; Chobert, Jean-Marc; Pourpak, Zahra; Moin, Mostafa; Moosavi-Movahedi, Ali Akbar; Haertle, Thomas


    Bovine beta-casein (beta-CN) is a highly amphiphilic micellising phospho-protein showing chaperone-like activity in vitro. Recently, existence of multiple sequential epitopes on beta-CN polypeptide chain in both hydrophilic-polar (psi) and hydrophobic-apolar domains (phi) has been evidenced. In order to clarify specific contribution of polar and apolar domains in micellisation process and in shaping immunoreactivity of beta-CN, its dimeric/bi-amphiphilic "quasi palindromic" forms covalently connected by a disulfide bond linking either N-terminal (C4 beta-CND) or C-terminal domain (C208 beta-CND) were produced and studied. Depending on the C- or N-terminal position of inserted cysteine, each dimeric beta-CN contains one polar/apolar region at the centre and two external hydrophobic/hydrophilic ends. Consequently, such casein dimers have radically different polarities/hydrophobicities on their outside surfaces. Dynamic light scattering (DLS) measurements indicate that these dimeric casein molecules form micelles of different sizes depending on arrangement of polar fragments of the beta-CN mutants in their constrained dimers. Non-aggregated dimers have different hydrodynamic diameters that could be explained by their different geometries. Measurements of fluorescence showed more hydrophobic environment of Trp residues of C208 beta-CND, while in similar experimental conditions Trp residues of C4 beta-CND and native beta-CN were more exposed to the polar medium. Both fluorescence and DLS studies showed greater propensity for micellisation of the dimeric beta-CNs, suggesting that the factors inducing the formation of micelles are stronger in the bi-amphiphilic dimers. 1-anilino-naphthalene-8-sulfonate (ANS) binding studies showed different binding of ANS by these dimers as well as different exposition of ANS binding (hydrophobic) regions in the micellar states. The differences in fluorescence resonance energy transfer (FRET) profiles of C4 beta-CND and C208 beta-CND can

  17. Resonant antineutrino induced electron capture with low energy bound-beta beams

    CERN Document Server

    Oldeman, R G C; Saitta, B


    Antineutrino induced electron capture is a resonant process that can have a larg e cross-section for beams of monochromatic antineutrinos. We calculate the cross-section of this process and investigate an experimental setup where monochromatic antineutrinos are produced from the bound-beta decay of fully ionized radioactive atoms in a storage ring. If the energy between the source and the target is well matched, the cross-sections can be significantly larger than the cross-sections of commonly used non-resonant processes. The rate that can be achieved at a small distance between the source and two targets of $10^3$ kg is up to one interaction per $8 .3\\cdot10^{18}$ decaying atoms. For a source-target distance corresponding to the first atmospheric neutrino osc illation maximum, the largest rate is one interaction per $3.2\\cdot10^{21}$ decaying atoms.

  18. Expression in Escherichia coli of cDNA encoding barley beta-amylase and properties of recombinant beta-amylase. (United States)

    Yoshigi, N; Okada, Y; Sahara, H; Koshino, S


    To express the cloned beta-amylase cDNA in Escherichia coli under control of the tac promoter, a plasmid pBETA92 was constructed. The plasmid consisted of 6312 bp. An extract of E. coli JM109 harboring pBETA92 had beta-amylase activity that produced beta-maltose from soluble starch. The enzyme production started in the logarithmic phase, increased linearly, and reached a maximum after 12 h. The recombinant barley beta-amylase gave two major (pI 5.43 and 5.63) and four minor (pI 5.20, 5.36, 5.80, and 6.13) activity bands on isoelectric focusing, and their pIs didn't change throughout the incubation. But Western blot analysis found that one beta-amylase having a molecular weight of about 56,000 was synthesized. The recombinant beta-amylase was purified from the cells by consecutive column chromatography. The purified enzyme gave a single band of protein on SDS-PAGE but showed heterogeneity on isoelectric focusing. The N-terminal amino acid sequence showed that the recombinant beta-amylase lacked four amino acids at positions 2-5 (Glu-Val-Asn-Val) when compared with the presumed amino acid sequence of barley beta-amylase. Therefore, the recombinant beta-amylase consisted of 531 amino acids, and its molecular weight was calculated to be 59,169. The N-terminal amino acid sequence of the recombinant beta-amylase and the nucleotide sequence of the junction position in plasmid pBETA92 indicated that GTG (Val-5 in the case of barley beta-amylase) at positions 27-29 from the SD sequence (AGGA) was the translation initiation codon. The properties of the recombinant beta-amylase were almost the same as those of barley beta-amylase except for the pI and the Km values for maltohexaose and maltoheptaose.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. The Promiscuity of [beta]-Strand Pairing Allows for Rational Design of [beta]-Sheet Face Inversion

    Energy Technology Data Exchange (ETDEWEB)

    Makabe, Koki; Koide, Shohei (UC)


    Recent studies suggest the dominant role of main-chain H-bond formation in specifying {beta}-sheet topology. Its essentially sequence-independent nature implies a large degree of freedom in designing {beta}-sheet-based nanomaterials. Here we show rational design of {beta}-sheet face inversions by incremental deletions of {beta}-strands from the single-layer {beta}-sheet of Borrelia outer surface protein A. We show that a {beta}-sheet structure can be maintained when a large number of native contacts are removed and that one can design large-scale conformational transitions of a {beta}-sheet such as face inversion by exploiting the promiscuity of strand-strand interactions. High-resolution X-ray crystal structures confirmed the success of the design and supported the importance of main-chain H-bonds in determining {beta}-sheet topology. This work suggests a simple but effective strategy for designing and controlling nanomaterials based on {beta}-rich peptide self-assemblies.

  20. Molecular analysis of beta-globin gene mutations among Thai beta-thalassemia children: results from a single center study

    Directory of Open Access Journals (Sweden)

    Boonyawat B


    Full Text Available Boonchai Boonyawat,1 Chalinee Monsereenusorn,2 Chanchai Traivaree2 1Division of Genetics, Department of Pediatrics, Phramongkutklao Hospital and College of Medicine, Bangkok, Thailand; 2Division of Hematology/Oncology, Department of Pediatrics, Phramongkutklao Hospital and College of Medicine, Bangkok, Thailand Background: Beta-thalassemia is one of the most common genetic disorders in Thailand. Clinical phenotype ranges from silent carrier to clinically manifested conditions including severe beta-thalassemia major and mild beta-thalassemia intermedia. Objective: This study aimed to characterize the spectrum of beta-globin gene mutations in pediatric patients who were followed-up in Phramongkutklao Hospital. Patients and methods: Eighty unrelated beta-thalassemia patients were enrolled in this study including 57 with beta-thalassemia/hemoglobin E, eight with homozygous beta-thalassemia, and 15 with heterozygous beta-thalassemia. Mutation analysis was performed by multiplex amplification refractory mutation system (M-ARMS, direct DNA sequencing of beta-globin gene, and gap polymerase chain reaction for 3.4 kb deletion detection, respectively. Results: A total of 13 different beta-thalassemia mutations were identified among 88 alleles. The most common mutation was codon 41/42 (-TCTT (37.5%, followed by codon 17 (A>T (26.1%, IVS-I-5 (G>C (8%, IVS-II-654 (C>T (6.8%, IVS-I-1 (G>T (4.5%, and codon 71/72 (+A (2.3%, and all these six common mutations (85.2% were detected by M-ARMS. Six uncommon mutations (10.2% were identified by DNA sequencing including 4.5% for codon 35 (C>A and 1.1% initiation codon mutation (ATG>AGG, codon 15 (G>A, codon 19 (A>G, codon 27/28 (+C, and codon 123/124/125 (-ACCCCACC, respectively. The 3.4 kb deletion was detected at 4.5%. The most common genotype of beta-thalassemia major patients was codon 41/42 (-TCTT/codon 26 (G>A or betaE accounting for 40%. Conclusion: All of the beta-thalassemia alleles have been characterized by

  1. Double side electroplating for applying beta voltaic with sandwich structure

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Sang Moo; Uhm, Young Rang; Son, Kwang Jae; Kim, Jong Bum; Kim, Jin Joo; Park, Jong Han [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)


    As a result, a variety of nuclear-based small-scale power sources have been developed with varying degrees of success and maturity. A nuclear battery with diode junction is a device that converts nuclear radiation directly to electric power. The mechanism of a nuclear battery is same as the P-N junction diode for solar cell application. The photovoltaic is operated by converted photons to electrical energy in the junction. In betavoltaic battery, beta particles are collected and converted to electrical energy as similar principle as photovoltaic. A very low current, order of nano or micro amperes, is generated in devices. The difference of the short circuit current between the pre-deposition and post deposition of Ni-63 was found to be 5 nA. This value is very low to apply device junction. To fabricate betavoltaic, Ni-63 should be coated on the double side of substrate. The bath was primarily composed of 0.2 M Ni ions, prepared by dissolving Ni metal particles in HCl. The prototype for electroplating radioactive Ni-63 on double side has been established.

  2. Loss management in the beta-beam decay ring

    CERN Document Server

    Chancé, Antoine


    The aim of the beta-beams is to produce pure electron neutrino and anti-neutrino highly energetic beams, coming from β-decay of the 18Ne10+ and 6He2+, both at γ = 100, directed towards experimental halls situated in the Fréjus tunnel [1], [2]. The high intensity ion beams are stored in a ring, until the ions decay. Consequently, all the injected particles will be lost anywhere around the ring generating a high level of irradiation. In order to keep a constant neutrino flux, the losses due to the decay of the radioactive ions are compensated with regular injections. The new ion beam is then merged with the stored beam with a specific RF program [3]. We have to consider two sources of losses: – The β-decay products: their magnetic rigidity being different from the reference one, they are bent differently and lost. – The losses during the injection merging process. The first one needs a particular ring design in order to insert appropriate beam stoppers at the right place. The second one needs a specific...

  3. The IRX-$\\beta$ relation: Insights from simulations

    CERN Document Server

    Safarzadeh, Mohammadtaher; Ferguson, Henry C


    We study the relationship between the UV continuum slope and infrared excess (IRX$\\equiv L_{\\rm IR}/L_{\\rm FUV}$) predicted by performing dust radiative transfer on a suite of hydrodynamical simulations of galaxies. Our suite includes both isolated disk galaxies and mergers intended to be representative of galaxies at both $z \\sim 0$ and $z \\sim 2-3$. Our low-redshift isolated disks and mergers often populate a region around the the locally calibrated \\citet[][M99]{M99} relation but move well above the relation during merger-induced starbursts. Our high-redshift simulated galaxies are blue and IR-luminous, which makes them lie above the M99 relation. The value of UV continuum slope strongly depends on the dust type used in the radiative transfer calculations: Milky Way-type dust leads to significantly more negative (bluer) slopes compared with Small Magellanic Cloud-type dust. The effect on $\\beta$ due to variations in the dust composition with galaxy properties or redshift can dominate over other sources of ...

  4. Considerations of beta and electron transport in internal dose calculations

    Energy Technology Data Exchange (ETDEWEB)

    Bolch, W.E.; Poston, J.W. Sr.


    Ionizing radiation has broad uses in modern science and medicine. These uses often require the calculation of energy deposition in the irradiated media and, usually, the medium of interest is the human body. Energy deposition from radioactive sources within the human body and the effects of such deposition are considered in the field of internal dosimetry. In July of 1988, a three-year research project was initiated by the Nuclear Engineering Department at Texas A M University under the sponsorship of the US Department of Energy. The main thrust of the research was to consider, for the first time, the detailed spatial transport of electron and beta particles in the estimation of average organ doses under the Medical Internal Radiation Dose (MIRD) schema. At the present time (December of 1990), research activities are continuing within five areas. Several are new initiatives begun within the second or third year of the current contract period. They include: (1) development of small-scale dosimetry; (2) development of a differential volume phantom; (3) development of a dosimetric bone model; (4) assessment of the new ICRP lung model; and (5) studies into the mechanisms of DNA damage. A progress report is given for each of these tasks within the Comprehensive Report. In each case, preliminary results are very encouraging and plans for further research are detailed within this document.

  5. Beowulf - Beta-Gamma Detector Calibration Graphical User Interface

    Energy Technology Data Exchange (ETDEWEB)

    McIntyre, Justin I.; Schrom, Brian T.; Cooper, Matthew W.; Haas, Derek A.; Hayes, James C.


    Pacific Northwest National Laboratory (PNNL) has demonstrated significant advancement in using beta-gamma coincidence detectors to detect a wide range of radioxenon isotopes. To obtain accurate activities with the detector it must be properly calibrated by measuring a series of calibration gas samples. The data is analyzed to create the calibration block used in the International Monitoring System file format. Doing the calibration manually has proven to be tedious and prone to errors, requiring a high degree of expertise. The Beowulf graphical user interface (GUI) is a software application that encompasses several components of the calibration task and generates a calibration block, as well as, a detailed report describing the specific calibration process used. This additional document can be used as a Quality assurance certificate to assist in auditing the calibration. This paper consists of two sections. Section 1 will describe the capabilities of Beowulf and section 2 will be a representative report generated or the 137Cs calibration and quality assurance source.

  6. Baseline ion production dedicated to beta-beams

    CERN Document Server

    Stora, Thierry


    Beta-beams, a concept introduced in 1991, require a large facility that produces and accelerates to high energy electron neutrino and antineutrino beams for oscillation experiments. They are produced by b decay of radioactive ion beams in a dedicated ring directed towards underground detectors. This article addresses the production of the 6He and 18Ne baseline ions. Part of the results were obtained within EURISOL-DS, a design study for the next generation OnLine Isotope Separation facility for nuclear physics in Europe. 200 kW, 2 GeV protons on a solid neutron spallation source surrounded by a thick beryllium oxide target produce the required 6He rates, while 18Ne production falls short by more than an order of magnitude. A first alternative might fulfil the objectives with a 30 MeV 3He primary beam onto large solid oxide target disks at several MW. A second 18Ne production alternative is based on a 700 kW proton beam at medium energy (70-160 MeV) and a target made of a circulating molten salt loop.

  7. Effects of amphetamine and beta-endorphin fragments on maze performance in rats

    NARCIS (Netherlands)

    Bohus, B; de Boer, S.F.


    Fragments of beta-endorphin and amphetamine cause similar effects in some tests of maze behavior in rats. The present study served to compare the influence of amphetamine and two beta-endorphin fragments [beta-endorphin (beta E)-(2-9) and beta E-(2-16)] on maze behavior in more detail. In Experiment

  8. Interactions of protein kinase CK2beta subunit within the holoenzyme and with other proteins

    DEFF Research Database (Denmark)

    Kusk, M; Ahmed, R; Thomsen, B;


    in alpha-beta and beta-beta interactions. We also detected an intramolecular beta interaction within the amino acid stretch 132-165. Using CK2beta as a bait in a two-hybrid library screening several new putative cellular partners have been identified, among them the S6 kinase p90rsk, the putative tumor...

  9. Blood flow measurements in the irradiated pig skin using {beta} emitters radionuclides; Mesure de la circulation sanguine cutanee chez le porc irradie a l`aide de radioisotopes emetteurs {beta}

    Energy Technology Data Exchange (ETDEWEB)

    Daburon, F.; Lefaix, J.L.; Leplat, J.J.; Fayart, G.; Delacroix, D.; Le Thanh, P.


    Non invasive methods of study of the skin blood flow are numerous, but generally do not give any indication on the cutaneous micro-circulatory flow, except for cutaneous laser Doppler. The isotopic exploration of the skin with injected {gamma} radionuclides, even of weak energy, doe snot allow to characterize the skin blood flow, because of the important contribution of the subcutaneous tissues. The use of {beta} emitters energy spectrum, analyzed by different quantitative methods, are proportional to the thickness of the screen localized between the radioactive source and detector. Using simple and complex phantoms composed of tissue equivalent screens, with {sup 32}P sources placed at different depths, it was possible to study the degradation of {beta} spectra, simulating respectively the sub-epidermis and sub-dermis vascular levels. A modelization and an experimental study in-vivo are proposed in this work, with {sup 32}P phosphate administered intravenously in pigs. (author).

  10. Primary and scattering contributions to beta scaled dose point kernels by means of Monte Carlo simulations; Contribuicoes primaria e espalhada para dosimetria beta calculadas pelo dose point kernels empregando simulacoes pelo Metodo Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Valente, Mauro [CONICET - Consejo Nacional de Investigaciones Cientificas y Tecnicas de La Republica Argentina (Conicet), Buenos Aires, AR (Brazil); Botta, Francesca; Pedroli, Guido [European Institute of Oncology, Milan (Italy). Medical Physics Department; Perez, Pedro, E-mail: [Universidad Nacional de Cordoba, Cordoba (Argentina). Fac. de Matematica, Astronomia y Fisica (FaMAF)


    Beta-emitters have proved to be appropriate for radioimmunotherapy. The dosimetric characterization of each radionuclide has to be carefully investigated. One usual and practical dosimetric approach is the calculation of dose distribution from a unit point source emitting particles according to any radionuclide of interest, which is known as dose point kernel. Absorbed dose distributions are due to primary and radiation scattering contributions. This work presented a method capable of performing dose distributions for nuclear medicine dosimetry by means of Monte Carlo methods. Dedicated subroutines have been developed in order to separately compute primary and scattering contributions to the total absorbed dose, performing particle transport up to 1 keV or least. Preliminarily, the suitability of the calculation method has been satisfactory, being tested for monoenergetic sources, and it was further applied to the characterization of different beta-minus radionuclides of nuclear medicine interests for radioimmunotherapy. (author)

  11. Responses of different dosemeters in beta dosimetry of {sup 106}Ru/{sup 106}Rh ophthalmic applicators;Respostas de diferentes dosimetros termoluminescentes na dosimetria beta de aplicadores oftalmicos de {sup 106}Ru/{sup 106}Rh

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, D.F.P.; Daros, K.A.C.; Segreto, R.A.; Medeiros, R.B. [Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, SP (Brazil)


    This work presents the TL response of three kinds of dosimeters from different manufacturing characteristics under irradiation of 106 Ru / 106 Rh sealed sources used in ophthalmic brachytherapy. They are: Ca SO{sub 4}:Dy + teflon (D- Ca SO{sub 4}:Dy -0,4), LiF:Mg, Ti (TLD-100) and Ca SO{sub 4}:Dy (TLD-900). Some of reports accepted by scientific community (NCS report 14 e ICRU report 72) as reference in the quality control of beta applicators dosimetry recommend that the absorbed dose standard uncertainties can be kept below 20%. The TLD Ca SO{sub 4}:Dy + teflon presented proper sensibility and high precision comparing with the others. Considering the similar dimensions of ophthalmic tumors and aside critical structures it is relevant to reduce undesirable effects due to the irradiation of these structures. Therefore, the quality control in the beta dosimetry using this kind of source is a constant challenge. (author)

  12. Tandem beta-enamino ester formation and cyclization with o-alkynyl anilines catalyzed by InBr3: efficient synthesis of beta-(N-indolyl)-alpha,beta-unsaturated esters. (United States)

    Murai, Kenichi; Hayashi, Shoko; Takaichi, Nobuhiro; Kita, Yasuyuki; Fujioka, Hiromichi


    A tandem reaction providing beta-(N-indolyl)-alpha,beta-unsaturated esters from beta-keto esters and o-alkynyl anilines was developed. Z-Alkenes were selectively formed due to the stability of the beta-enamino ester as an intermediate of the reaction. This reaction includes the intermolecular beta-enamino ester formation and intramolecular cyclization catalyzed by InBr(3).

  13. beta-delayed fission from sup 2 sup 3 sup 0 Ac

    CERN Document Server

    Yang Wei Fan; Xu Yan Bing; Xong Bing; Pan Qiang Yan; He Jian Jun; Xiao Yong Hou; Li Yi


    ThO sub 2 is irradiated with 60 MeV/u sup 1 sup 8 O beams. sup 2 sup 3 sup 0 Ra is produced via the multi-nucleon transfer and dissipative fragmentation reactions of the target. sup 2 sup 3 sup 0 Ra is radio-chemical separated from ThO sub 2 and the other reaction products. The thin Ra sources are prepared. The mica fission track detectors are exposed to the Ra sources. gamma-rays of Ra decay in the sources are measured by a HPGe detector. The mica foil is etched in HF solution. The etched mica foil is scanned with an optical microscope. The fission tracks that should come from beta-delayed fission of sup 2 sup 3 sup 0 Ac are observed. The beta-delayed fission probability of sup 2 sup 3 sup 0 Ac is determined to be (1.19 +- 0.85) x 10 sup - sup 8

  14. TL glow curve analysis of UV, beta and gamma induced limestone collected from Amarnath holy cave

    Directory of Open Access Journals (Sweden)

    Vikas Dubey


    Full Text Available The paper reports themoluminescence glow curve analysis of UV (ultraviolet, β (beta and γ (gamma induced limestone collected from Amarnath holy cave. The collected natural sample was characterized by X-ray diffraction (XRD technique and crystallite size calculated by Scherer's formula. Surface morphology and particle size was calculated by transmission electron microscopy (TEM study. Effect of annealing temperature on collected lime stone examined by TL glow curve study. The limestone was irradiated by UV radiation (254 nm source and the TL glow curve recorded for different UV exposure time. For beta irradiation Sr90 source was used and is shows intense peak at 256 °C with a shoulder peak at higher temperature range. For gamma radiation Co60 source and TL glow curve recorded for different doses of gamma. The kinetic parameters calculation was performed for different glow curve by computerized glow curve deconvolution (CGCD technique. The chemical composition of natural limestone was analyzed by energy dispersive X-ray spectroscopy (EDXS.

  15. Plasma transforming growth factor beta levels in breast cancer patients

    NARCIS (Netherlands)

    Sminia, P; Barten, AD; Van Waarde, MAWH; Vujaskovic, Z; Van Tienhoven, G


    We investigated whether the concentration of circulating transforming growth factor beta (TGF beta) yields diagnostic value in breast cancer. Blood was collected from twenty stage I and II breast cancer patients both prior to treatment and after surgical excision of the tumour. Both latent and activ

  16. Genetics Home Reference: mucolipidosis II alpha/beta (United States)

    ... lysosomes, including mucolipidosis II alpha/beta , are called lysosomal storage disorders. The signs and symptoms of mucolipidosis II alpha/beta are most likely caused by the lack of digestive enzymes within lysosomes and the effects these enzymes have outside the cell. Mutations in ...

  17. Beta-agonisten : stand van zaken en prognoses

    NARCIS (Netherlands)

    Schilt, R.; Haasnoot, W.; Huf, F.A.


    Op dit moment zijn de Beta-agonisten clenbuterol, mabuterol, salbutamol, cimalerol en terbutaline zowel met een multi-screeningsmethode als met een multi-bevestigingsmethode te bepalen. Op korte termijn is te verwachten dat de Beta-agonisten bamethaan, orciprenaline (= metaproterenol) en isoproteren

  18. Monitoring of beta-receptor sensitivity in cardiac surgery

    DEFF Research Database (Denmark)

    Yndgaard, S; Lippert, F K; Bigler, Dennis Richard


    To determine the repeatability of the hemodynamic response to repeated isoproterenol challenge doses to validate the standardized isoproterenol sensitivity test as an index of cardiovascular beta-receptor function.......To determine the repeatability of the hemodynamic response to repeated isoproterenol challenge doses to validate the standardized isoproterenol sensitivity test as an index of cardiovascular beta-receptor function....

  19. AGS vertical beta function measurements for Run 15

    Energy Technology Data Exchange (ETDEWEB)

    Harper, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ahrens, L. [Brookhaven National Lab. (BNL), Upton, NY (United States); Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Schoefer, V. [Brookhaven National Lab. (BNL), Upton, NY (United States)


    One key parameter for running the AGS efficiently is by maintaining a low emittance. To measure emittance, one needs to measure the beta function throughout the cycle. This can be done by measuring the beta function at the ionization profile monitors (IPM) in the AGS. This tech note delves into the motivation, the measurement, and some strides that were made throughout Run15.

  20. Synthesis of conformationally restricted beta-turn mimics

    NARCIS (Netherlands)

    IJsselstijn, Maarten


    This thesis aims at developing methods for introducing conformational restriction in Beta-turns, the turn elements present in Beta-sheets. A conformationally restricted peptide might either be formed via incorporation of a bridging diamino acids in a growing peptide chain, or via covalent bond formi