Science.gov

Sample records for magnetica funcional rmf

  1. Selecting RMF Controls for National Security Systems

    SciTech Connect

    Witzke, Edward L.

    2015-08-01

    In 2014, the United States Department of Defense started tra nsitioning the way it performs risk management and accreditation of informatio n systems to a process entitled Risk Management Framework for DoD Information Technology or RMF for DoD IT. There are many more security and privacy contro ls (and control enhancements) from which to select in RMF, than there w ere in the previous Information Assurance process. This report is an attempt t o clarify the way security controls and enhancements are selected. After a brief overview and comparison of RMF for DoD I T with the previously used process, this report looks at the determination of systems as National Security Systems (NSS). Once deemed to be an NSS, this report addr esses the categorization of the information system with respect to impact level s of the various security objectives and the selection of an initial baseline o f controls. Next, the report describes tailoring the controls through the use of overl ays and scoping considerations. Finally, the report discusses organizatio n-defined values for tuning the security controls to the needs of the information system.

  2. Description of C isotopes within RMF+BCS approach

    NASA Astrophysics Data System (ADS)

    Saxena, G.; Singh, D.; Kaushik, M.

    2013-06-01

    In the present investigations we have employed relativistic mean-field plus BCS (RMF + BCS) approach to carry out a systematic study for the ground state properties of even-even C Isotopes. One of the prime reason of this study has been to look into the role of low lying states in neutron rich reason near neutron drip line. It is found that irrespective of whether any resonant state exists or not, the occupancy of weakly bound neutron single particle states having low orbital angular momentum, (l = 0 or 1), with a well spread wave function due to the absence or very small strength of centrifugal barrier, helps to cause the occurrence of nuclei with widely extended neutron density. Such nuclei are found to have characteristically very small two-neutron separation energy and large neutron rms radius akin to that observed in weakly bound systems.

  3. Description of C isotopes within RMF+BCS approach

    SciTech Connect

    Saxena, G.; Singh, D.; Kaushik, M.

    2013-06-03

    In the present investigations we have employed relativistic mean-field plus BCS (RMF + BCS) approach to carry out a systematic study for the ground state properties of even-even C Isotopes. One of the prime reason of this study has been to look into the role of low lying states in neutron rich reason near neutron drip line. It is found that irrespective of whether any resonant state exists or not, the occupancy of weakly bound neutron single particle states having low orbital angular momentum, (l = 0 or 1), with a well spread wave function due to the absence or very small strength of centrifugal barrier, helps to cause the occurrence of nuclei with widely extended neutron density. Such nuclei are found to have characteristically very small two-neutron separation energy and large neutron rms radius akin to that observed in weakly bound systems.

  4. Actividad funcional cerebral en estado de reposo: REDES EN CONEXIÓN

    PubMed Central

    Proal, Erika; Alvarez-Segura, Mar; de la Iglesia-Vayá, Maria; Martí-Bonmatí, Luis; Castellanos, F. Xavier

    2015-01-01

    Resumen El análisis de la conectividad funcional mediante resonancia magnética funcional (RMf) puede llevarse a cabo durante la realización de una tarea, la percepción de un estímulo o en estado de reposo. Estos análisis han demostrado su fiabilidad y reproducibilidad con diferentes enfoques (matemáticos, estadísticos, físicos) para seleccionar los vóxeles activados. El estudio de la señal de baja frecuencia en la actividad cerebral a través del contraste BOLD en estado de reposo ha revelado patrones de actividad cortical sincronizados, permitiendo describir la arquitectura funcional intrínseca del cerebro humano. La comunidad científica internacional dispone de recursos compartidos que contribuirán mediante este análisis de RMf en estado de reposo a la obtención de diagnósticos y tratamientos más precisos y avanzados en el campo de las neurociencias. PMID:21365601

  5. RMF concept: a rotating-magnetic-field technique for driving steady plasma currents in compact toroid devices

    SciTech Connect

    McKenna, K.F.

    1980-09-01

    The generation and/or sustaining of a Compact Toroid (CT) configuration using the RMF technique is a relatively new and unknown concept. In this report the basic principles, historical development, and current theoretical understanding of this concept are reviewed. Significant experimental and theoretical results, potential problem areas, and recommendations for the direction of future work are discussed. An illustrative analysis of the application of the RMF technique to a CT reactor is presented. The results of a recent experiment, the Rotamak, in which a Spheromak-like CT plasma was produced using the RMF technique, are presented.

  6. A fixed-grid method for transient simulations of dopant segregation in VGF-RMF growth

    NASA Astrophysics Data System (ADS)

    Nikrityuk, Petr A.; Pätzold, Olf; Stelter, Michael

    2012-01-01

    In this work a fixed-grid, virtual-front tracking model originally developed for modeling dendritic growth has been adopted for transient simulations of dopant segregation in vertical gradient freeze (VGF) melt growth of Ga-doped germanium under the influence of a rotating magnetic field (RMF). The interfacial Stefan conditions for temperature and solute are formulated in volumetric terms in energy and solute conservation equations, which allow the interface to be tracked implicitly with no need to calculate the growth velocity. The model and the code are validated against an analytical solution for the transient solidification of a binary alloy at constant velocity. The numerical results show the strong relationship between the melt flow pattern and the dopant concentration in the crystal grown. The better melt mixing during growth under the influence of RMF is found to have a significant impact on the axial and radial macrosegregation of dopants. Simulation results are in good qualitative agreement with previous experimental observations of the dopant segregation in VGF-RMF growth, which now are seen ass a direct consequence of the mixing state of the melt.

  7. How Hibernation Factors RMF, HPF, and YfiA Turn Off Protein Synthesis

    SciTech Connect

    Polikanov, Yury S.; Blaha, Gregor M.; Steitz, Thomas A.

    2013-04-08

    Eubacteria inactivate their ribosomes as 100S dimers or 70S monomers upon entry into stationary phase. In Escherichia coli, 100S dimer formation is mediated by ribosome modulation factor (RMF) and hibernation promoting factor (HPF), or alternatively, the YfiA protein inactivates ribosomes as 70S monomers. Here, we present high-resolution crystal structures of the Thermus thermophilus 70S ribosome in complex with each of these stationary-phase factors. The binding site of RMF overlaps with that of the messenger RNA (mRNA) Shine-Dalgarno sequence, which prevents the interaction between the mRNA and the 16S ribosomal RNA. The nearly identical binding sites of HPF and YfiA overlap with those of the mRNA, transfer RNA, and initiation factors, which prevents translation initiation. The binding of RMF and HPF, but not YfiA, to the ribosome induces a conformational change of the 30S head domain that promotes 100S dimer formation.

  8. Application of photo-detection to art and archaeology at the C2RMF

    NASA Astrophysics Data System (ADS)

    Calligaro, T.; Dran, J.-C.; Klein, M.

    2003-05-01

    The Centre for research and restoration of the museums of France (C2RMF), located in the Louvre palace in Paris routinely uses photodetector-based techniques for the study of objects of cultural heritage. Among these methods, the ion beam analysis techniques (IBA) provided by the 2-MV electrostatic accelerator "AGLAE" installed in the C2RMF have the specific qualities required for the study of these valuable objects. Indeed, PIXE and PIGE are non-destructive, non-invasive, rapid and sensitive tools for the determination of the chemical composition. Their use enables to answer three major questions in the field of Art and Archaeology: (1) identification of the material, (2) determination of the provenance, and (3) study of surface modification (ageing, alteration). Applications of radiation detectors are exemplified through case studies performed at the Centre: the identification of the pigments used on an Egyptian papyrus, the provenance of gemstones set on ancient jewels and the indirect dating of archaeological flints. New trends in the use of photo-detectors in Art and Archaeology are presented.

  9. Preliminary Results on a Low-Energy RMF-FRC Experiment with Water

    NASA Astrophysics Data System (ADS)

    Uchizono, Nolan; Hill, Carrie; Holmes, Michael

    2015-11-01

    The U.S. Air Force Research Laboratory-Edwards has developed a new Field-Reversed Configuration (FRC) test cell for researching low-energy (<15J) FRC formation physics. This test cell is currently outfitted with a cylindrical Rotating Magnetic Field (RMF) FRC plasma source. FRC's are compatible with a variety of propellants - including complex propellants, like water and CO2. Water was the propellant of choice for this experiment. The input conditions of the test cell were varied to study their effects on FRC formation and plasma content. FRC formation was studied using a suite of diagnostics, including voltage and current probes, and excluded-flux measurements. Plasma species composition was studied using a residual gas analyzer, and optical emission spectroscopy. The propellant decomposition and ionization stage used in this experiment is presented in companion work at this conference.

  10. Experimental investigation and numerical simulation of triggered vacuum arc behavior under TMF/RMF-AMF contact

    NASA Astrophysics Data System (ADS)

    Wang, Lijun; Deng, Jie; Qin, Kang; Zhang, Xiao; Jia, Shenli

    2016-06-01

    A series of triggering experiments was carried out to investigate the characteristics of vacuum arc controlled by TMF/RMF-AMF contacts. During all the experiments, the current ranged from 5–20 kA (rms) and both the arc appearance and behavior of cathode spots were captured by high-speed camera with corresponding arc current and arc voltage. A 3D steady magnetohydrodynamics (MHD) model was built to simulate and analyze the vacuum arc behavior under TMF/RMF-AMF contacts, and arc plasma parameters were calculated based on the above model. The experimental results showed that arc deflection was visible under both low and high current. Under high current, arc core formed, which meant the arc contracted significantly. In addition, the anode became much more active under high current. The behavior of the cathode spots showed that they split themselves into other new cathode spots. Under high current, the bulk of the spots rotated along a clockwise direction on a transverse magnetic field (TMF) plate, which caused much noise and oscillation in the arc voltage. The simulation results show that ions are likely to gather on the branches of the TMF plate on the anode plane, as a result of the effects between the electromagnetic force and pressure gradient of the arc plasma. The current contracts in the center of the TMF plate on the cathode which was due to the thin connecting rod there. The anode contraction of the current is caused by the Hall effect. Ions move along a clockwise direction on the TMF plate, which is driven by Ampere force. The current contraction resulted in significant melting in the center of the cathode surface while the other region suffered from uniform melting. The melting caused by the anode contraction is more significant than that of the cathode.

  11. Effect of Rotating Magnetic Field (RMF) on Segregation of Solute Elements in CuNi10Fe1Mn Alloy Hollow Billet

    NASA Astrophysics Data System (ADS)

    Yan, Zhiming; Jin, Wenzhong; Li, Tingju

    2012-09-01

    The effect of rotating magnetic field (RMF) on macro/microsegregation of solute elements is investigated experimentally, and a comprehensive three-dimensional mathematical model is built, and the finite element package ANSYS® is employed to calculate the distribution of temperature and liquid fraction along the radial direction in horizontal continuous casting of CuNi10Fe1Mn alloy hollow billet. The results show that RMF makes the temperature field and liquid fraction uniform. The original inhomogeneous columnar grain macrostructure turns into homogeneous equiaxed grain structure, and the macro/microsegregation of Ni, Fe, and Mn elements are restrained effectively with the application of RMF. Moreover, the action mechanism of RMF is discussed to explain its effect on improving the distribution of solute elements.

  12. Ion heating in the field-reversed configuration (FRC) by rotating magnetic fields (RMF) near cyclotron resonance

    SciTech Connect

    Samuel A. Cohen; Alan H. Glasser

    2000-07-20

    The trajectories of ions confined in a Solovev FRC equilibrium magnetic geometry and heated with a small-amplitude, odd-parity rotating magnetic field, have been studied with a Hamiltonian computer code. When the RMF frequency is in the ion-cyclotron range, explosive heating occurs. Higher-energy ions are found to have betatron-type orbits, preferentially localized near the FRC midplane. These results are relevant to a compact magnetic-fusion-reactor design.

  13. Preliminary Results on a low-energy RMF-FRC Plasma Translation Experiment for Space Propulsion

    NASA Astrophysics Data System (ADS)

    Hill, Carrie; Uchizono, Nolan; Holmes, Michael

    2015-11-01

    The U.S. Air Force Research Laboratory-Edwards has developed a new experimental test cell to study the translation physics of Field-Reversed-Configurations (FRC) formed at low-energy (<15 J/pulse). The test-cell is currently equipped with a conical Rotating Magnetic Field (RMF) source, capable of producing a burst of 10 plasmoids at 5 J/pulse. This source has been characterized at full energy with a xenon propellant at a range of flow rates (5-70 sccm), bias fields up to 500 G, and antenna phasing. Data from a suite of diagnostics has been analyzed to track plasmoid formation and axial motion. These diagnostics include voltage and current probes, axial magnetic field probes, magnetic flux loops, and Langmuir probes. A time-of-flight array measures the plasmoid's exit velocity. Emission spectroscopy using streak-imaging is also implemented. A basic global energy balance from these diagnostics is used to estimate the efficiency of the translation process and determine how it scales with magnetic field, flow rate, and antenna phasing.

  14. ?`Es necesario calcular detalladamente funciones de partición atómicas?

    NASA Astrophysics Data System (ADS)

    Milone, L. A.; Merlo, D. C.

    Basándonos en extensos y precisos cómputos de funciones de partición realizados por nosotros para distintos átomos, se muestra que en el cálculo u obtención de ciertas magnitudes (notablemente la presión electrónica, la abundancia de un elemento deducida a partir de un estado fuertemente ionizado, etc.) el error porcentual que se comete es pequeño (inferior a 1 %) si se adopta, como valor de la función de partición, el peso estadístico del término correspondiente al estado fundamental del átomo. Esta notable simplificación acelera el cálculo, por ejemplo, de un modelo de atmósfera estelar, sin disminuir la precisión de los resultados.

  15. Funciones de partición atómicas: Fuentes confiables de datos

    NASA Astrophysics Data System (ADS)

    Merlo, D. C.; Milone, L. A.

    Se llevó a cabo una revisión minuciosa del cálculo de funciones de partición atómicas de átomos livianos, en estados neutro y una vez ionizados, partiendo del Hidrógeno y llegando al Sodio, incluyendo también al K I y el Ca II. Al respecto, se realizó una investigación exhaustiva de referencias bibliográficas existentes hasta el presente, las cuales fueron cotejadas con cálculos propios llevados a cabo mediante el procedimiento de depresión del contínuo (0.001 a 0.5 eV). Nuestros resultados muestran un muy buen acuerdo con las expresiones interpolatorias de Traving et al (1966), al presente, la referencia más completa en cuanto a especies atómicas consideradas. Puntualizamos, además, ciertas deficiencias de estas relaciones de ajuste para decrementos del potencial de ionización altos (Δ χ >= 0.5) eV).

  16. Familiares a cargo de pacientes de cáncer: funciones y desafíos (PDQ®)—Versión para profesionales de salud

    Cancer.gov

    Sumario informativo revisado por expertos acerca de los desafíos que enfrentan los familiares a cargo de los pacientes con cáncer. Este resumen se centra en las funciones típicas y las inquietudes de las personas a cargo del paciente y en las intervenciones útiles para esas personas.

  17. Endogenous retrovirus and radiation-induced leukemia in the RMF mouse

    SciTech Connect

    Tennant, R.W.; Boone, L.R.; Lalley, P.; Yang, W.K.

    1982-01-01

    The induction of myeloid leukemia in irradiated RFM/Un mice has been associated with retrovirus infection. However, two characteristics of this strain complicate efforts to define the role of the virus. This strain possesses only one inducible host range class of endogenous virus and a unique gene, in addition to the Fv-1/sup n/ locus, which specifically restricts exogenous infection by endogenous viruses. These characteristics possibly account for absence of recombinant viruses in this strain, even though virus is amply expressed during most of the animal's life span. We have examined further the distribution of retrovirus sequences and the chromosomal locus of the inducible virus in this strain. This report describes evidence for additional viral sequences in cells of a radiation-induced myeloid leukemia line and discusses the possible origin of these added copies.

  18. Conditioning of In-Situ Propellants for RMF-FRC Plasma Thrusters

    NASA Astrophysics Data System (ADS)

    Holmes, Michael; Hill, Carrie; Uchizono, Nolan

    2015-11-01

    Current ion thrusters use noble gases to limit chemical attack of thruster components. However, thrusters based on Field Reversed Configuration (FRC) plasmas need not directly contact propellants so that reactive propellants such as ammonia, methane, butane, water, or combination of these are possible. The practical need to convert liquid propellant to a gaseous partially ionized state is what drives our research. A decomposition device was built to transition from liquid to gas to partially ionized plasma. Pressure is maintained high enough so that all chemical components have residence times sufficiently long to complete phase change and to reach chemical equilibrium at high temperature so the gas consists of primarily of H2O, H2, N2, O2, CO, and CO2. This gas is then fed to an inductive discharge that further breaks down molecules and brings the propellant to the proper ionization configuration for the FRC. We will be measuring chemical state, ionization state, and uniformity as propellant enters the discharge region. A parallel FRC thruster effort is underway.

  19. Declinazione magnetica: storia delle prime misure e misura con l'azimut del Sole

    NASA Astrophysics Data System (ADS)

    Sigismondi, Costantino

    2016-05-01

    The magnetic declination is the compass deviation from astronomical North. Georg Hartmann in 1510 in Rome firstly measured it as 6° East. Using accurate solar ephemerides and a UTC synchronized watch, the shadow of a vertical pole is astronomically referenced. The angles of a 10m size triangle including the direction of this shadow, the solar azimuth, and the magnetic North give the magnetic declination with an accuracy of 2 arcmin.

  20. Regulación del flujo sanguíneo uterino. II. Funciones de estrógeno y receptores estrogénicos α/β en acciones genómicas y no-genómicas del endotelio uterino *

    PubMed Central

    Mayra, Pastore R.; Rosalina, Villalón L.; López, Gladys; Iruretagoyena, Jesús; Magness, Ronald

    2015-01-01

    Resumen El embarazo está marcado por cambios y adaptaciones cardiovasculares que son importantes para el crecimiento y mantenimiento de la placenta y el feto. Durante este periodo, las adaptaciones vasculares uterinas manifiestan cambios clasificados como de corto o largo plazo los cuales están relacionados con adaptaciones vasodilatadoras, angiogénicas o de remodelación. El estrógeno y los receptores estrogénicos clásicos (REs), RE-α y RE-β, han demostrado ser parcialmente responsables por facilitar el incremento dramático en el fluido sanguíneo uterino necesario durante el embarazo. En ésta revisión bibliográfica se discuten la base estructural para la diversidad y selectividad funcional de los REs por el estrógeno, el papel de los REs sobre los efectos genómicos y no-genómicos en células endoteliales de arterias uterinas (CEAU). Estos temas integran el conocimiento científico sobre la regulación molecular de CEAU para mantener el incremento fisiológico en la perfusión útero-placentaria observada durante un embarazo normal. PMID:26113751

  1. Neurotrophins, cytokines, oxidative parameters and funcionality in Progressive Muscular Dystrophies.

    PubMed

    Comim, Clarissa M; Mathia, Gisiane B; Hoepers, Andreza; Tuon, Lisiane; Kapczinski, Flávio; Dal-Pizzol, Felipe; Quevedo, João; Rosa, Maria I

    2015-09-01

    We investigated the levels of brain derived-neurotrophic factor (BDNF), cytokines and oxidative parameters in serum and tried to correlate them with the age and functionality of patients with Progressive Muscle Dystrophies (PMD). The patients were separated into six groups (case and controls pared by age and gender), as follows: Duchenne Muscular Dystrophy (DMD); Steinert Myotonic Dystrophy (SMD); and Limb-girdle Muscular Dystrophy type-2A (LGMD2A). DMD patients (± 17.9 years old) had a decrease of functionality, an increase in the IL-1β and TNF-α levels and a decrease of IL-10 levels and superoxide dismutase activity in serum. SMD patients (± 25.8 years old) had a decrease of BDNF and IL-10 levels and superoxide dismutase activity and an increase of IL-1β levels in serum. LGMD2A patients (± 27.7 years old) had an decrease only in serum levels of IL-10. This research showed the first evidence of BDNF involvement in the SMD patients and a possible unbalance between pro-inflammatory and anti-inflammatory cytokine levels, along with decreased superoxide dismutase activity in serum of DMD and SMD patients. PMID:25910175

  2. [Funcion sparing surgery in uro-oncology: germ cell tumors of the testis].

    PubMed

    Catanzaro, Mario; Piva, Luigi; Torelli, Tullio; Biasoni, Davide; Stagni, Silvia; Milani, Angelo; Necchi, Andrea; Giannatempo, Patrizia; Nicolai, A; Salvioni, Roberto

    2012-01-01

    Surgery in germ cell tumors of the testis (TGT) may result in andrological disorders, both after orchiectomy and after retroperitoneal lymphadenectomy (RPLND). Bilateral orchiectomy suppresses both testicular functions: exocrine and endocrine. In selected cases with bilateral TGT (metachronous/synchronous), or in the case of TGT in monorchid patients, partial orchiectomy (enucleation of the tumor) can preserve both functions with a low risk of relapse in residual testicular parenchyma, in the absence of intraepithelial neoplasia (TIN). In cases of TIN and normal testosterone levels (80%), the fertility is maintained in 50% of patients. In these cases the use of radiotherapy on the residual testicular parenchyma can prevent the future development of invasive cancer, though compromising the hormonal function. The RPLND (open or laparoscopic) can produce major side effects, such as retrograde ejaculation. Knowledge of the adrenergic fiber retroperitoneal neuroanatomy enables to implement a "nerve sparing" surgery with an almost total reduction of this serious side effect, but that option is only available in few centers of excellence. Semen cryopreservation has become a common practice performed before any treatment that might impact on the andrological function of patients. PMID:23371266

  3. Espanol para el hispanohablante. Funcion y nocion (Spanish for the Spanish Speaker. Function and Notion).

    ERIC Educational Resources Information Center

    Blanco, George M.; And Others

    A guide to the development of Spanish-language curricula for Spanish-speaking secondary students is intended to help teachers and administrators design programs building on students' existing language strengths. The recommended instructional approach is functional-notional, and local districts are encouraged to use it to adapt their textbooks and…

  4. Mecanismos de plasticidad (funcional y dependiente de actividad) en el cerebro auditivo adulto y en desarrollo

    PubMed Central

    Izquierdo, M.A.; Oliver, D.L.; Malmierca, M.S.

    2010-01-01

    Summary Introduction and development Sensory systems show a topographic representation of the sensory epithelium in the central nervous system. In the auditory system this representation originates tonotopic maps. For the last four decades these changes in tonotopic maps have been widely studied either after peripheral mechanical lesions or by exposing animals to an augmented acoustic environment. These sensory manipulations induce plastic reorganizations in the tonotopic map of the auditory cortex. By contrast, acoustic trauma does not seem to induce functional plasticity at subcortical nuclei. Mechanisms that generate these changes differ in their molecular basis and temporal course and we can distinguish two different mechanisms: those involving an active reorganization process, and those that show a simple reflection of the loss of peripheral afferences. Only the former involve a genuine process of plastic reorganization. Neuronal plasticity is critical for the normal development and function of the adult auditory system, as well as for the rehabilitation needed after the implantation of auditory prostheses. However, development of plasticity can also generate abnormal sensation like tinnitus. Recently, a new concept in neurobiology so-called ‘neuronal stability’ has emerged and its implications and conceptual basis could help to improve the treatments of hearing loss. Conclusion A combination of neuronal plasticity and stability is suggested as a powerful and promising future strategy in the design of new treatments of hearing loss. PMID:19340783

  5. Modification of bacterial cellulose through exposure to the rotating magnetic field.

    PubMed

    Fijałkowski, Karol; Żywicka, Anna; Drozd, Radosław; Niemczyk, Agata; Junka, Adam Feliks; Peitler, Dorota; Kordas, Marian; Konopacki, Maciej; Szymczyk, Patrycja; Fray, Mirosława El; Rakoczy, Rafał

    2015-11-20

    The aim of the study was to assess the influence of rotating magnetic field (RMF) on production rate and quality parameters of bacterial cellulose synthetized by Glucanacetobacter xylinus. Bacterial cultures were exposed to RMF (frequency f=50Hz, magnetic induction B=34mT) for 72h at 28°C. The study revealed that cellulose obtained under RMF influence displayed higher water absorption, lower density and less interassociated microfibrils comparing to unexposed control. The application of RMF significantly increased the amount of obtained wet cellulose pellicles but decreased the weight and thickness of dry cellulose. Summarizing, the exposure of cellulose-synthesizing G. xylinus to RMF alters cellulose biogenesis and may offer a new biotechnological tool to control this process. As RMF-modified cellulose displays better absorbing properties comparing to non-modified cellulose, our finding, if developed, may find application in the production of dressings for highly exudative wounds. PMID:26344254

  6. Application of a rotating magnetic field to semiconductor crystal growth in Space

    NASA Astrophysics Data System (ADS)

    Senchenkov, A. S.; Barmin, I. V.

    2003-12-01

    To eliminate the tremendous influence of the residual accelerations on homogeneity of the crystal growing in a space experiment, a rotating magnetic field (RMF) is used. A number of the experiments have been performed in space within the RMF both in the frame of the Russian national program and together with European scientists. In the paper some theoretical and experimental results illustrating the effectiveness of RMF application to crystal growth under microgravity conditions are presented. Tables 2, Figs 5, Refs 8.

  7. The filtration of molten 1XXX series aluminum alloys with rigid media tube filter

    SciTech Connect

    Hoshino, K.; Nishizaka, T.; Kakimoto, K.; Yoshida, T.

    1996-10-01

    Recently it has been increasing that molten 1XXX series aluminum alloys are filtered by Rigid Media Tube Filters (RMF). In that case, it occasionally happens that the pressure drop across the RMF rapidly increases in its relatively early stage of use. The authors have investigated inclusions captured in the RMF and conducted some model tests to define the cause. Consequently the mechanism of the rapid increase of pressure drop is given.

  8. Educacion Ambiental en las Escuelas: Creando una Programa que Funcione! (Environmental Education in the Schools: Creating a Program That Works!).

    ERIC Educational Resources Information Center

    Braus, Judy A.; Wood, David

    This book is a manual that enables teachers to formulate an effective program of environmental education across multiple grade levels and cultural settings. A section provides tips for using the book, followed by nine chapters dealing with different aspects of developing and implementing an environmental education program. Chapter 1 presents a…

  9. Evaluación de funciones de distribución de pares condicionales para objetos no interactuantes

    NASA Astrophysics Data System (ADS)

    Zurbriggen, E.; Rohrmann, R. D.

    Spatial distributions of objects are ubiquous in astronomy (e.g., particles in a gas, stars in a cluster, galaxies in the Universe). Here, we introduce a novel function for the analysis of the spatial structures: a pair distribution function conditioned by information in which each object has a nearest neighbour to a specific distance. We show its application to randomly distributed, non- interacting objects. FULL TEXT IN SPANISH

  10. Masculinos y femeninos en funcion diminutiva y aumentativa (Masculine and Feminine Genders Used in Diminutive and Augmentative Functions)

    ERIC Educational Resources Information Center

    Carnicer, Ramon

    1975-01-01

    Some Spanish nouns designating non-animate things may have either feminine or masculine gender. The reasons given for the choice of gender are many and varied. It is put forward that in some cases the masculine acts as a diminutive and the feminine as an augmentative. (Text is in Spanish.) (TL)

  11. Moderate-intensity rotating magnetic fields do not affect bone quality and bone remodeling in hindlimb suspended rats.

    PubMed

    Jing, Da; Cai, Jing; Wu, Yan; Shen, Guanghao; Zhai, Mingming; Tong, Shichao; Xu, Qiaoling; Xie, Kangning; Wu, Xiaoming; Tang, Chi; Xu, Xinmin; Liu, Juan; Guo, Wei; Jiang, Maogang; Luo, Erping

    2014-01-01

    Abundant evidence has substantiated the positive effects of pulsed electromagnetic fields (PEMF) and static magnetic fields (SMF) on inhibiting osteopenia and promoting fracture healing. However, the osteogenic potential of rotating magnetic fields (RMF), another common electromagnetic application modality, remains poorly characterized thus far, although numerous commercial RMF treatment devices have been available on the market. Herein the impacts of RMF on osteoporotic bone microarchitecture, bone strength and bone metabolism were systematically investigated in hindlimb-unloaded (HU) rats. Thirty two 3-month-old male Sprague-Dawley rats were randomly assigned to the Control (n = 10), HU (n = 10) and HU with RMF exposure (HU+RMF, n = 12) groups. Rats in the HU+RMF group were subjected to daily 2-hour exposure to moderate-intensity RMF (ranging from 0.60 T to 0.38 T) at 7 Hz for 4 weeks. HU caused significant decreases in body mass and soleus muscle mass of rats, which were not obviously altered by RMF. Three-point bending test showed that the mechanical properties of femurs in HU rats, including maximum load, stiffness, energy absorption and elastic modulus were not markedly affected by RMF. µCT analysis demonstrated that 4-week RMF did not significantly prevent HU-induced deterioration of femoral trabecular and cortical bone microarchitecture. Serum biochemical analysis showed that RMF did not significantly change HU-induced decrease in serum bone formation markers and increase in bone resorption markers. Bone histomorphometric analysis further confirmed that RMF showed no impacts on bone remodeling in HU rats, as evidenced by unchanged mineral apposition rate, bone formation rate, osteoblast numbers and osteoclast numbers in cancellous bone. Together, our findings reveal that RMF do not significantly affect bone microstructure, bone mechanical strength and bone remodeling in HU-induced disuse osteoporotic rats. Our study indicates potentially

  12. Moderate-Intensity Rotating Magnetic Fields Do Not Affect Bone Quality and Bone Remodeling in Hindlimb Suspended Rats

    PubMed Central

    Shen, Guanghao; Zhai, Mingming; Tong, Shichao; Xu, Qiaoling; Xie, Kangning; Wu, Xiaoming; Tang, Chi; Xu, Xinmin; Liu, Juan; Guo, Wei; Jiang, Maogang; Luo, Erping

    2014-01-01

    Abundant evidence has substantiated the positive effects of pulsed electromagnetic fields (PEMF) and static magnetic fields (SMF) on inhibiting osteopenia and promoting fracture healing. However, the osteogenic potential of rotating magnetic fields (RMF), another common electromagnetic application modality, remains poorly characterized thus far, although numerous commercial RMF treatment devices have been available on the market. Herein the impacts of RMF on osteoporotic bone microarchitecture, bone strength and bone metabolism were systematically investigated in hindlimb-unloaded (HU) rats. Thirty two 3-month-old male Sprague-Dawley rats were randomly assigned to the Control (n = 10), HU (n = 10) and HU with RMF exposure (HU+RMF, n = 12) groups. Rats in the HU+RMF group were subjected to daily 2-hour exposure to moderate-intensity RMF (ranging from 0.60 T to 0.38 T) at 7 Hz for 4 weeks. HU caused significant decreases in body mass and soleus muscle mass of rats, which were not obviously altered by RMF. Three-point bending test showed that the mechanical properties of femurs in HU rats, including maximum load, stiffness, energy absorption and elastic modulus were not markedly affected by RMF. µCT analysis demonstrated that 4-week RMF did not significantly prevent HU-induced deterioration of femoral trabecular and cortical bone microarchitecture. Serum biochemical analysis showed that RMF did not significantly change HU-induced decrease in serum bone formation markers and increase in bone resorption markers. Bone histomorphometric analysis further confirmed that RMF showed no impacts on bone remodeling in HU rats, as evidenced by unchanged mineral apposition rate, bone formation rate, osteoblast numbers and osteoclast numbers in cancellous bone. Together, our findings reveal that RMF do not significantly affect bone microstructure, bone mechanical strength and bone remodeling in HU-induced disuse osteoporotic rats. Our study indicates potentially

  13. Ribosome Modulation Factor, an Important Protein for Cell Viability Encoded by the Polyamine Modulon*

    PubMed Central

    Terui, Yusuke; Tabei, Yuzuru; Akiyama, Mariko; Higashi, Kyohei; Tomitori, Hideyuki; Yamamoto, Kaneyoshi; Ishihama, Akira; Igarashi, Kazuei; Kashiwagi, Keiko

    2010-01-01

    We searched for proteins whose synthesis is enhanced by polyamines at the stationary phase of cell growth using an Escherichia coli polyamine-requiring mutant in which cell viability is greatly decreased by polyamine deficiency. The synthesis of ribosome modulation factor (RMF) was strongly enhanced by polyamines at the level of translation at the stationary phase of cell growth. In rmf mRNA, a Shine-Dalgarno (SD) sequence is located 11 nucleotides upstream of the initiation codon AUG. When the SD sequence was moved to the more common position 8 nucleotides upstream of the initiation codon, the degree of polyamine stimulation was reduced, although the level of RMF synthesis was markedly increased. Polyamine stimulation of RMF synthesis was found to be caused by a selective structural change of the bulged-out region of the initiation site of rmf mRNA. The decrease in cell viability caused by polyamine deficiency was prevented by the addition of a modified rmf gene whose synthesis is not influenced by polyamines. The results indicate that polyamines enhance cell viability of E. coli at least in part by enhancing RMF synthesis. PMID:20628056

  14. Spin-orbit and orbit-orbit strengths for the radioactive neutron-rich doubly magic nucleus {sup 132}Sn in relativistic mean-field theory

    SciTech Connect

    Liang Haozhao; Zhao Pengwei; Li Lulu; Meng Jie

    2011-01-15

    Relativistic mean-field (RMF) theory is applied to investigate the properties of the radioactive neutron-rich doubly magic nucleus {sup 132}Sn and the corresponding isotopes and isotones. The two-neutron and two-proton separation energies are well reproduced by the RMF theory. In particular, the RMF results agree with the experimental single-particle spectrum in {sup 132}Sn as well as the Nilsson spin-orbit parameter C and orbit-orbit parameter D thus extracted, but remarkably differ from the traditional Nilsson parameters. Furthermore, the present results provide a guideline for the isospin dependence of the Nilsson parameters.

  15. Bridgman Growth of Germanium Crystals in a Rotating Magnetic Field

    NASA Technical Reports Server (NTRS)

    Volz, M. P.; Szofran, F. R.; Cobb, S. D.; Schweizer, M.; Walker, J. S.

    2005-01-01

    A series of (100)-oriented gallium-doped germanium crystals has been grown by the vertical Bridgman method and under the influence of a rotating magnetic field (RMF). Time-dependent flow instabilities occur when the critical magnetic Taylor number (Tm(sup c)) is exceeded, and this can be observed by noting the appearance of striations in the grown crystals. Tm(sup c) decreases as the aspect ratio of the melt increases, and approaches the theoretical limit expected for an infinite cylinder. Intentional interface demarcations are introduced by pulsing the RMF on and off The RMF has a marked affect on the interface shape, changing it from concave to nearly flat as the RMF strength is increased.

  16. Bridgman Growth of Germanium Crystals in a Rotating Magnetic Field

    NASA Technical Reports Server (NTRS)

    Volz, M. P.; Walker, J. S.; Schweizer, M.; Cobb, S. D.; Szofran, F. R.

    2004-01-01

    A series of (100)-oriented gallium-doped germanium crystals have been grown by the Bridgman method and under the influence of a rotating magnetic field (RMF). Time-dependent flow instabilities occur when the critical magnetic Taylor number (Tm(sup c) is exceeded, and this can be observed by noting the appearance of striations in the grown crystals. The experimental data indicate that Tm(sup c) increases as the aspect ratio of the melt decreases. Modeling calculations predicting Tm(sup c) as a function of aspect ratio are in reasonable agreement with the experimental data. The RMF has a marked affect on the interface shape, changing it from concave to nearly flat as the RMF strength is increased. Also, by pulsing the RMF on and off, it is shown that intentional interface demarcations can be introduced.

  17. Convection Induced by High Frequency Rotating Magnetic Field in Ionic Aqueous Solutions

    NASA Technical Reports Server (NTRS)

    Volz, Martin P.; Mazuruk, Konstantin

    2000-01-01

    Rotating magnetic fields (RMF) have found applications in modern metallurgy. Examples are casting and semiconductor crystal growth technology. Rotating convective flows can also be induced in ionic fluids. Due to optical transparency, these fluids offer a great opportunity to visualize convection. In this work, we investigate the dynamics of convection induced by a high frequency (100 kHz range) RMF. A dye injected into a cylindrical column of salty water serves as an indicator of the flow. The developed technique has been used to study mixing phenomena induced by a RMF both when the direc'tion of the field rotation is constant and when it is alternated. Optical recording has been used to analyze this process. A numerical model describing RMF mixing in the laminar regime will also be presented.

  18. La intimidacion en el comienzo de la adolescencia: La funcion del grupo social (Bullying in Early Adolescence: The Role of the Peer Group). ERIC Digest.

    ERIC Educational Resources Information Center

    Espelage, Dorothy L.

    One notable gap in the evolving literature on bullying and victimization during early adolescence is the role that peers play in promoting such behavior by either reinforcing the aggressor, failing to intervene to stop the victimization, or affiliating with students who bully. This Spanish-language Digest looks at the limited research available on…

  19. Personal de enfermería asume diversas funciones con expansión de programas de gestión para pacientes

    Cancer.gov

    Artículo sobre los profesionales de enfermería oncológica que ayudan a los pacientes durante todas las etapas de la atención oncológica, desde los exámenes de detección y el diagnóstico, hasta el tratamiento y la supervivencia.

  20. Funcion del "Vulgo" en la Preception Dramatica de la Edad de Oro (The Function of the "Masses" in the Didactic Drama of the [Spanish] Golden Age).

    ERIC Educational Resources Information Center

    Porqueras Mayo, A.; Sanchez Escribano, F.

    1967-01-01

    A concept of the masses, or populace, conveyed a positive connotation in both Biblical and Renaissance literature. During Spain's Golden Age (seventeenth century) writers, especially didactic dramatists, tended to register negative and prejudiced attitudes toward the common folk and to regard them as "masa inculta" or uncultured masses. Primarily,…

  1. The Influence of a Rotating Magnetic Field on Solidification from a Traveling Solvent Zone

    NASA Technical Reports Server (NTRS)

    Gillies, Donald C.

    1997-01-01

    Application of a high frequency rotating magnetic field (50-400Hz) (RMF) with a strength of the order of 1 mT can be used to influence the fluid flow in an electrically conductive melt. The advantage of the RMF during the traveling solvent zone method for growth of semiconductor materials will be discussed. Preliminary modeling results for cadmium telluride growth from a tellurium solvent zone will be discussed.

  2. Controls for orbital assembly of large space structures

    NASA Technical Reports Server (NTRS)

    Balas, Mark J.; Davidson, Roger; Gooyabadi, Ali A.; Quan, Ralph; Reisenauer, Brian; Robertson, L.; Mohl, James; Good, Philip; Vredevoogd, Loren; Galvez, Jose

    1991-01-01

    The topics covered are presented in viewgraph form and include the following: flexible structure control; decentralized control for flexible multi-body systems; control of structures during assembly; decentralized control using structural partitioning; reduced-orded model-based controller design; ROM/residual mode filters (RMF) control of large flexible structures;RMF in a distributed parameter system (DPS); LSS active control simulation; 3-D truss beam; mobile transporter with RMS; and flexible robot manipulator.

  3. Observations of improved confinement in field reversed configurations sustained by antisymmetric rotating magnetic fields

    SciTech Connect

    Guo, H.Y.; Hoffman, A.L.; Steinhauer, L.C.

    2005-06-15

    Rotating magnetic fields (RMF) have been employed to both form and sustain currents in field reversed configurations (FRC). A major concern about this method has been the fear of opening up magnetic field lines with even small ratios of vacuum RMF B{sub {omega}} to external confinement field B{sub e}. A recently proposed innovation was to use an antisymmetric arrangement of RMF, but vacuum calculations with full RMF penetration showed that very low values of B{sub {omega}}/B{sub e} would still be required to provide field-line closure. Recent comparisons of symmetric and antisymmetric RMF drive on the translation, confinement, and sustainment (TCS) facility [A. L. Hoffman, H. Y. Guo, J. T. Slough et al., Fusion Sci. Technol. 41, 92 (2002)] have shown strong improvements in the basic confinement properties of the FRCs when using antisymmetric drive, even with ratios of B{sub {omega}}/B{sub e} as high as 0.3. This is due to normal standard operation with only partial penetration of the RMF beyond the FRC separatrix. The uniform transverse RMF in vacuum is shielded by the conducting plasma, resulting in a mostly azimuthal field near the FRC separatrix with a very small radial component. Simple numerical calculations using analytical solutions for the partially penetrated antisymmetric RMF, superimposed on Grad-Shafranov solutions for the poloidal FRC fields, show good field-line closure for the TCS experimental conditions. The antisymmetric arrangement also leads to more efficient current drive and improved stabilization of rotational modes.

  4. Generation of Whistler Wave by a Rotating Magnetic Field Source

    NASA Astrophysics Data System (ADS)

    Karavaev, A.; Papadopoulos, K.; Shao, X.; Sharma, A. S.; Gigliotti, A.; Gekelman, W.; Pribyl, P.; Vincena, S.

    2008-12-01

    The interaction of Rotating Magnetic Fields (RMF) with plasmas is a fundamental plasma physics problem with implications to fusion related Field-Reversed Configurations (FRC), space propulsion, astronaut protection from cosmic rays in long interstellar travel, control of the energetic population in the radiation belts and near zone processes in pulsar magnetospheres. In this paper we report recent experiments on the generation of whistler waves with a new type RMF-based antenna. The experiments were conducted on UCLA's Large Plasma Device (LAPD). The Rotating Magnetic Field (RMF) is created using poly-phased loop antennas. A number of parameter combinations, e.g. plasma density, background magnetic field, and driving current, were used. It was found that RMF created by a two phase-delayed loop antenna drives significant currents along the ambient magnetic field. The measured amplitude of induced wave field was proportional to the square-root of the plasma density. The spatial decay rate for the wave perturbation across the background magnetic field was found to scale with the plasma skin depth. A small amplitude second harmonic was also measured. The paper will also present analytic and simulation results that account for the experimental results; in particular, the scaling of the induced magnetic field as a function of the RMF and plasma parameters and the spatial decay rate of magnetic field. Applications of RMF as an efficient radiation source of plasma waves in space plasmas will be discussed. This work was sponsored by ONR MURI Grant 5-28828

  5. BACKPRESSURE TESTING OF ROTARY MICROFILTER DISKS

    SciTech Connect

    Fowley, M.; Herman, D.

    2011-04-14

    The Savannah River National Laboratory (SRNL), under the Department of Energy (DOE) Office of Environmental Management (EM), is modifying and testing the SpinTek{trademark} rotary microfilter (RMF) for radioactive filtration service in the Department of Energy (DOE) complex. The RMF has been shown to improve filtration throughput when compared to other conventional methods such as cross-flow filtration. A concern with the RMF was that backpressure, or reverse flow through the disk, would damage the filter membranes. Reverse flow might happen as a result of an inadvertent valve alignment during flushing. Testing was completed in the Engineering Development Laboratory (EDL) located in SRNL to study the physical effects of backpressure as well as to determine the maximum allowable back-pressure for RMF disks. The RMF disks tested at the EDL were manufactured by SpinTek{trademark} Filtration and used a Pall Corporation PMM050 filter membrane (0.5 micron nominal pore size) made from 316L stainless steel. Early versions of the RMF disks were made from synthetic materials that were incompatible with caustic solutions and radioactive service as well as being susceptible to delaminating when subjected to backpressure. Figure 1-1 shows the essential components of the RMF; 3 rotating disks and 3 stationary turbulence promoters (or shear elements) are shown. Figure 1-2 show the assembly view of a 25 disk RMF proposed for use at the Savannah River Site (SRS) and at the Hanford Facility. The purpose of the testing discussed in this report was to determine the allowable backpressure for RMF disks as well as study the physical effects of backpressure on RMF disks made with the Pall PMM050 membrane. This was accomplished by pressurizing the disks in the reverse flow direction (backpressure) until the test limit was reached or until membrane failure occurred. Backpressure was applied to the disks with air while submerged in deionized (DI) water. This method provided a visual

  6. SU-E-T-47: Application of the Repair-Misrepair-Fixation RBE Model to Describe the Results of High Resolution Proton Irradiation Cell Survival Experiments

    SciTech Connect

    Peeler, C; Bronk, L; Taleei, R; Guan, F; Grosshans, D; Mirkovic, D; Titt, U; Mohan, R

    2014-06-01

    Purpose: To develop a system to rapidly and accurately calculate RBE with the repair-misrepair-fixation (RMF) model for proton therapy data sets and to evaluate its effectiveness in modeling RBE for cell survival experiments performed with the H460 cell line for a range of proton LET. Methods: A system for using the Monte Carlo Damage Simulation (MCDS) software with high performance computing was developed. Input for the MCDS software for a range of proton energies in increments of 0.1 MeV was generated and simulated. The output data were then used to determine doseaveraged quantities for the RMF model based on equivalently binned proton energy spectra. The method was applied to calculate RBE at 50% survival for experimental cell survival data. Experimental data were obtained using a system which allowed for the accumulation of cell survival data at known values of dose-averaged proton LETs at a range of doses. RBE was calculated based directly on a Cs-137 reference experiment and, additionally, according to fitted values of the θ and κ terms of the RMF model. Results: Dose-averaged RMF model quantities were calculated using the HPC system. Compared to experimental RBE determined using a Cs-137 irradiation as a reference, the RBE from the model differed by at most 49%. RBE based on the fitted values of θ and κ differed by at most 18% for the highest LET. Conclusion: A system for rapidly generating data necessary to calculate RBE with the RMF model has been developed. For the H460 cell line, the RMF model could not reproduce the experimentally determined RBE based solely on the photon reference data. Fitting of the θ and κ terms of the RMF model indicates that their values increase for proton LET exceeding approximately 10 keV/µm. NIH Program Project Grant P01CA021239.

  7. Pitch Angle Scattering of Energetic Particles by Waves Generated from a Rotating Magnetic Field Source

    NASA Astrophysics Data System (ADS)

    Shao, X.; Karavaev, A. V.; Sharma, A. S.; Papadopoulos, K.; Gumerov, N.; Gigliotti, A. F.; Gekelman, W. N.

    2009-12-01

    Injection of whistler waves into Earth's inner radiation belt to enhance precipitation of energetic electrons has been an active research area, and is referred to as RB Remediation (RBR). Most mechanisms of pitch angle scattering of energetic particles are based on gyro-resonant wave-particle interaction. Recent experiments and simulations show that Rotating Magnetic Field (RMF) antennas in plasmas can be efficient radiation sources of MHD and whistler waves. In experiments conducted in the Large Plasma Device (LAPD) at UCLA, poly-phased current loops drove the RMF antenna. These experiments, as well as simulations show that 75-85% of the radiation generated by the RMF antenna is in guided propagation. The whistler and MHD waves have non-local magnetic field gradients in the transverse direction and these provide ways to break the adiabatic invariants of electrons and precipitate them via a non-resonant scattering. In this paper simulations of non-resonant pitch angle scattering of energetic particles by waves generated by RMF sources are presented. Three-dimensional EMHD simulations are used to model whistlers and the resultant 3D electromagnetic fields are used in particle tracing codes to study pitch angle scattering. The simulations are carried out for a wide range of magnetic fields produced by RMF sources, including fields much larger than the ambient magnetic field in space plasma environments. This work was sponsored by ONR MURI Grant 5-28828

  8. Rotating magnetic field current drive of high-temperature field reversed configurations with high {zeta} scaling

    SciTech Connect

    Guo, H. Y.; Hoffman, A. L.; Milroy, R. D.

    2007-11-15

    Greatly reduced recycling and impurity ingestion in the Translation, Confinement, and Sustainment--Upgrade (TCSU) device has allowed much higher plasma temperatures to be achieved in the field reversed configurations (FRC) under rotating magnetic field (RMF) formation and sustainment. The hotter plasmas have higher magnetic fields and much higher diamagnetic electron rotation rates so that the important ratio of average electron rotation frequency to RMF frequency, called {zeta}, approaches unity, for the first time, in TCSU. A large fraction of the RMF power is absorbed by an as yet unexplained (anomalous) mechanism directly proportional to the square of the RMF magnitude. It becomes of relatively lesser significance as the FRC current increases, and simple resistive heating begins to dominate, but the anomalous absorption is useful for initial plasma heating. Measurements of total absorbed power, and comparisons of applied RMF torque to torque on the electrons due to electron-ion friction under high-{zeta} operation, over a range of temperatures and fields, have allowed the separation of the classical Ohmic and anomalous heating to be inferred, and cross-field plasma resistivities to be calculated.

  9. Dynamic Magnetic Field Applications for Materials Processing

    NASA Technical Reports Server (NTRS)

    Mazuruk, K.; Grugel, Richard N.; Motakef, S.; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    Magnetic fields, variable in time and space, can be used to control convection in electrically conducting melts. Flow induced by these fields has been found to be beneficial for crystal growth applications. It allows increased crystal growth rates, and improves homogeneity and quality. Particularly beneficial is the natural convection damping capability of alternating magnetic fields. One well-known example is the rotating magnetic field (RMF) configuration. RMF induces liquid motion consisting of a swirling basic flow and a meridional secondary flow. In addition to crystal growth applications, RMF can also be used for mixing non-homogeneous melts in continuous metal castings. These applied aspects have stimulated increasing research on RMF-induced fluid dynamics. A novel type of magnetic field configuration consisting of an axisymmetric magnetostatic wave, designated the traveling magnetic field (TMF), has been recently proposed. It induces a basic flow in the form of a single vortex. TMF may find use in crystal growth techniques such as the vertical Bridgman (VB), float zone (FZ), and the traveling heater method. In this review, both methods, RMF and TMF are presented. Our recent theoretical and experimental results include such topics as localized TMF, natural convection dumping using TMF in a vertical Bridgman configuration, the traveling heater method, and the Lorentz force induced by TMF as a function of frequency. Experimentally, alloy mixing results, with and without applied TMF, will be presented. Finally, advantages of the traveling magnetic field, in comparison to the more mature rotating magnetic field method, will be discussed.

  10. The effect of rotating magnetic field on the microstructure of in situ TiB2/Cu composites

    NASA Astrophysics Data System (ADS)

    Zou, C.; Kang, H.; Li, R.; Li, M.; Wang, W.; Chen, Z.; Wang, T.

    2016-03-01

    Nano ceramic particulate reinforced metal matrix composites are confronted with the problem of particle aggregation emerging in the process of solidification. It sharply deteriorates the mechanical properties of the composites. In order to improve the microstructure and particle distribution, in situ TiB2/Cu composites were prepared using Ti and Cu-B master alloys in a vacuum medium frequency induction furnace equipped with a rotating magnetic field (RMF). The effect of RMF magnetic field intensity employed on the microstructure and particles distribution of the TiB2/Cu composites were investigated. The results show that with the applied RMF, TiB2 particles are homogeneously distributed in the copper matrix, which significantly improves the mechanical properties of TiB2/Cu composites. The mechanism of RMF may be ascribed to the following two aspects. On the one hand, the electromagnetic body force generated by appropriate RMF drives forced convection in the equatorial plane of composite melt during solidification. On the other hand, a secondary flow in the meridional plane is engendered by a radial pressure gradient, thus making a strong agitation in the melt. These two effects result in a homogenous dispersion of TiB2 particles in the copper matrix, and hence excellent properties of TiB2/Cu composites were obtained.

  11. Numerical Simulation of THM Growth of CdTe in Presence of Rotating Magnetic Fields

    NASA Technical Reports Server (NTRS)

    Ghaddar, Chahid K.; Lee, Cheo K.; Motakef, Sharihar; Gillies, Donald

    1998-01-01

    The influence of rotating magnetic fields (RMF) on the flow pattern and compositional uniformity in the solution zone of a traveling heater method (THM) system for growth of CdTe is numerically investigated. The analysis is conducted at the 10(exp -6) and 10(exp -1) g(sub 0) as representative of space and ground processing conditions. It is shown that under microgravity conditions, application of RMF can be used to overwhelm residual buoyancy-induced convection and to control the uniformity of solution-zone composition at the growth front without appreciable modification of the growth interface shape. At high gravity levels, RMF is found not to be able to completely dominate buoyancy-induced convection. In this regime, for the range of field strengths studied, RMF is found to result in a) complex flow structures in the solution zone, b) enhancement of compositional non-uniformities at the growth front, and c) increased convexity of the growth interface. A scaling analysis of convection in the solution zone is used to generate a non-dimensional map delineating the RMF- and gravity-dominated flow regimes.

  12. Application of Rotating Magnetic Fields to THM Growth Process: Te-CdTe

    NASA Technical Reports Server (NTRS)

    LeClair, Mark; Worlikar, Ani; Motakef, Shariar; Gillies, Donald C.

    1998-01-01

    The numerical simulation of ongoing traveling heater method (THM) solution growth experiments of CdTe from Te solvent and the influence of a Rotating Magnetic Field (RMF) on control of convection in the solution zone is presented. The application of RMF is pursued as a means to actively control thermo-solutal convection in the solution zone which otherwise would be dominated by buoyancy forces. Numerical simulation and scaling analysis are used to generate a flow-regime map demarcating the boundary separating the buoyancy- and RMF-driven convection in the solution zone. Results indicate that whereas at low gravity levels the application of RMF can completely overwhelm buoyancy-induced convection, at normal gravity levels the successful control of convection by RMF requires use of fairly thin solvent zones. Simulation results also indicate that field strengths required to dominate natural convection on earth may lead to instabilities and transition to turbulence, and an associated deleterious effect on the quality of grown crystals. These and other simulations results are discussed in reference to experimental evidence.

  13. Resurrection of Rhynchoplax Stimpson, 1858, with the description of two new species from Japan and Australia (Crustacea: Decapoda: Brachyura: Hymenosomatidae).

    PubMed

    Komai, Tomoyuki; Poore, Gary C B

    2016-01-01

    Rhynchoplax Stimpson, 1858, is resurrected from synonymy with Halicarcinus White, 1846. Rhynchoplax hondai Takeda & Miyake, 1971, a species based on an immature female, is rediagnosed and two new species, R. magnetica n. sp. from northeastern Australia and R. minutula n. sp. from the Ryukyu Islands, Japan, are described. They differ from R. hondai in the shape of the rostrum, form of the subhepatic region and the armature of the pereopodal meri. All differ from the type species R. messor Stimpson, 1858, in having a longer and simple rostrum without supraocular pseudorostral spines and the absence of a postocular spine. PMID:27394510

  14. Stochastic Ion Heating in a Field-reversed Configuration Geometry by Rotating Magnetic Fields

    SciTech Connect

    S.A. Cohen, A.S. Landsman, and A.H. Glasser

    2007-06-25

    Ion heating by application of rotating magnetic fields (RMF) to a prolate field-reversed configuration(FRC) is explored by analytical and numerical techniques. For odd-parity RMF (RMFo), perturbation analysis shows ions in figure-8 orbits gain energy at resonances of the RMFo frequency, ωR, with the figure-8 orbital frequency, ω. Since figure-8 orbits tend to gain the most energy from the RMF and are unlikely to escape in the cusp region (where most losses occur), they are optimal candidates for rapid stochastic heating, as compared to cyclotron and betatron orbits. Comparisons are made between heating caused by even- and odd-parity RMFs and between heating in currently operating and in reactor-scale FRC devices.

  15. Nuclear reaction cross sections of exotic nuclei in the Glauber model for relativistic mean field densities

    SciTech Connect

    Patra, S. K.; Panda, R. N.; Arumugam, P.; Gupta, Raj K.

    2009-12-15

    We have calculated the total nuclear reaction cross sections of exotic nuclei in the framework of the Glauber model, using as inputs the standard relativistic mean field (RMF) densities and the densities obtained from the more recently developed effective-field-theory-motivated RMF (the E-RMF). Both light and heavy nuclei are taken as the representative targets, and the light neutron-rich nuclei as projectiles. We found the total nuclear reaction cross section to increase as a function of the mass number, for both the target and projectile nuclei. The differential nuclear elastic scattering cross sections are evaluated for some selected systems at various incident energies. We found a large dependence of the differential elastic scattering cross section on incident energy. Finally, we have applied the same formalism to calculate both the total nuclear reaction cross section and the differential nuclear elastic scattering cross section for the recently discussed superheavy nucleus with atomic number Z=122.

  16. Could non-destructive methodologies enhance the microbiologically influenced corrosion (MIC) in pipeline systems?

    NASA Astrophysics Data System (ADS)

    Al-Abbas, F.; Kakpovbia, A.; Mishra, B.; Olson, D.; Spear, J.

    2013-01-01

    Stringent corrosion management programs are being deployed by oil and gas industry to ensure the integrity of pipeline systems. Parts of this program are the corrosion protection systems and inspection detection methods included non-destructive techniques. Those measures induce remnant magnetic field (RMF) in the pipeline steel. Potentially the RMF could affect the corrosion process in the pipeline including microbiologically influenced corrosion (MIC). Microorganisms in pipelines have surface charges and produce a wide variety of metabolic products. Consequently, when they are exposed to RMF generated at the linepipe steel surface by the aforementioned sources there will be potential effects. This sequentially will increase the likelihood of biofilm formation and hence enhance/promote MIC. This study investigates the potential effects of RFM on the MIC by sulfate reducing bacteria (SRB).

  17. Superscaling Predictions for Neutral Current Quasielastic Neutrino-Nucleus Scattering

    SciTech Connect

    Martinez, M. C.; Udias, J. M.; Caballero, J. A.; Donnelly, T. W.

    2008-02-08

    The application of superscaling ideas to predict neutral-current (NC) quasielastic (QE) neutrino cross sections is investigated. The relativistic impulse approximation (RIA) using the same relativistic mean field potential (RMF) for both initial and final nucleons -- a model that reproduces the experimental (e,e{sup '}) scaling function -- is used to illustrate our findings. While NC reactions are apparently not well suited for scaling analyses, to a large extent, the RIA-RMF predictions do exhibit superscaling. Independence of the scaled response on the nuclear species is very well fulfilled. The RIA-RMF NC superscaling function is in good agreement with the experimental (e,e{sup '}) one. The idea that electroweak processes can be described with a universal scaling function, provided that mild restrictions on the kinematics are assumed, is shown to be valid.

  18. Bridgman Growth of Germanium Crystals in a Rotating Magnetic Field

    NASA Technical Reports Server (NTRS)

    Volz, M. P.; Schweizer, M.; Cobb, S. D.; Walker, J. S.; Szofran, F. R.; Curreri, Peter A. (Technical Monitor)

    2002-01-01

    A series of (100)-oriented gallium-doped germanium crystals have been grown by the Bridgman method and under the influence of a rotating magnetic field (RMF). The RMF has a marked affect on the interface shape, changing it from concave to nearly flat. The onset of time-dependent flow instabilities occurs when the critical magnetic Taylor number is exceeded, and this can be observed by noting the appearance of striations in the grown crystals. The critical magnetic Taylor number is a sensitive function of the aspect ratio and, as the crystal grows under a constant applied magnetic field, the induced striations change from nonperiodic to periodic, undergo a period-doubling transition, and then cease to exist. Also, by pulsing the RMF on and off, it is shown that intentional interface demarcations can be introduced.

  19. Shot noise of charge current in a quantum dot responded by rotating and oscillating magnetic fields

    SciTech Connect

    Zhao, Hong-Kang Zou, Wei-Ke; Chen, Qiao

    2014-09-07

    We have investigated the shot noise and Fano factor of the dynamic spin-polarized quantum dot under the perturbations of a rotating magnetic field (RMF), and an oscillating magnetic field (OMF) by employing the non-equilibrium Green's function approach. The shot noise is enhanced from sub-Poissonian to super-Poissonian due to the application of RMF and OMF, and it is controlled sensitively by the tilt angle θ of RMF. The magnitude of shot noise increases as the photon energy ℏω of OMF increases, and its valley eventually is reversed to peaks as the photon energy is large enough. Double-peak structure of Fano factor is exhibited as the frequency of OMF increases to cover a large regime. The Zeeman energy μ{sub 0}B{sub 0} acts as an effective gate bias to exhibit resonant behavior, and novel peak emerges associated with the applied OMF.

  20. Shot noise of charge current in a quantum dot responded by rotating and oscillating magnetic fields

    NASA Astrophysics Data System (ADS)

    Zhao, Hong-Kang; Zou, Wei-Ke; Chen, Qiao

    2014-09-01

    We have investigated the shot noise and Fano factor of the dynamic spin-polarized quantum dot under the perturbations of a rotating magnetic field (RMF), and an oscillating magnetic field (OMF) by employing the non-equilibrium Green's function approach. The shot noise is enhanced from sub-Poissonian to super-Poissonian due to the application of RMF and OMF, and it is controlled sensitively by the tilt angle θ of RMF. The magnitude of shot noise increases as the photon energy ℏω of OMF increases, and its valley eventually is reversed to peaks as the photon energy is large enough. Double-peak structure of Fano factor is exhibited as the frequency of OMF increases to cover a large regime. The Zeeman energy μ0B0 acts as an effective gate bias to exhibit resonant behavior, and novel peak emerges associated with the applied OMF.

  1. Controller-structure interaction compensation using adaptive residual mode filters

    NASA Technical Reports Server (NTRS)

    Davidson, Roger A.; Balas, Mark J.

    1990-01-01

    It is not feasible to construct controllers for large space structures or large scale systems (LSS's) which are of the same order as the structures. The complexity of the dynamics of these systems is such that full knowledge of its behavior cannot by processed by today's controller design methods. The controller for system performance of such a system is therefore based on a much smaller reduced-order model (ROM). Unfortunately, the interaction between the LSS and the ROM-based controller can produce instabilities in the closed-loop system due to the unmodeled dynamics of the LSS. Residual mode filters (RMF's) allow the systematic removal of these instabilities in a matter which does not require a redesign of the controller. In addition RMF's have a strong theoretical basis. As simple first- or second-order filters, the RMF CSI compensation technique is at once modular, simple and highly effective. RMF compensation requires knowledge of the dynamics of the system modes which resulted in the previous closed-loop instabilities (the residual modes), but this information is sometimes known imperfectly. An adaptive, self-tuning RMF design, which compensates for uncertainty in the frequency of the residual mode, has been simulated using continuous-time and discrete-time models of a flexible robot manipulator. Work has also been completed on the discrete-time experimental implementation on the Martin Marietta flexible robot manipulator experiment. This paper will present the results of that work on adaptive, self-tuning RMF's, and will clearly show the advantage of this adaptive compensation technique for controller-structure interaction (CSI) instabilities in actively-controlled LSS's.

  2. Principal physics of rotating magnetic-field current drive of field reversed configurations

    SciTech Connect

    Hoffman, A.L.; Guo, H.Y.; Miller, K.E.; Milroy, R.D.

    2006-01-15

    After extensive experimentation on the Translation, Confinement, and Sustainment rotating magnetic-field (RMF)-driven field reversed configuration (FRC) device [A. L. Hoffman et al., Fusion Sci. Technol. 41, 92 (2002)], the principal physics of RMF formation and sustainment of standard prolate FRCs inside a flux conserver is reasonably well understood. If the RMF magnitude B{sub {omega}} at a given frequency {omega} is high enough compared to other experimental parameters, it will drive the outer electrons of a plasma column into near synchronous rotation, allowing the RMF to penetrate into the plasma. If the resultant azimuthal current is strong enough to reverse an initial axial bias field B{sub o} a FRC will be formed. A balance between the RMF applied torque and electron-ion friction will determine the peak plasma density n{sub m}{proportional_to}B{sub {omega}}/{eta}{sup 1/2}{omega}{sup 1/2}r{sub s}, where r{sub s} is the FRC separatrix radius and {eta} is an effective weighted plasma resistivity. The plasma total temperature T{sub t} is free to be any value allowed by power balance as long as the ratio of FRC diamagnetic current, I{sup '}{sub dia}{approx_equal}2B{sub e}/{mu}{sub o}, is less than the maximum possible synchronous current, I{sup '}{sub sync}=e{omega}r{sub s}{sup 2}/2. The RMF will self-consistently penetrate a distance {delta}{sup *} governed by the ratio {zeta}=I{sup '}{sub dia}/I{sup '}{sub sync}. Since the FRC is a diamagnetic entity, its peak pressure p{sub m}=n{sub m}kT{sub t} determines its external magnetic field B{sub e}{approx_equal}(2{mu}{sub o}p{sub m}){sup 1/2}. Higher FRC currents, magnetic fields, and poloidal fluxes can thus be obtained, with the same RMF parameters, simply by raising the plasma temperature. Higher temperatures have also been noted to reduce the effective plasma resistivity, so that these higher currents can be supported with surprisingly little increase in absorbed RMF power.

  3. Effects of triaxial deformation and pairing correlation on the proton emitter {sup 145}Tm

    SciTech Connect

    Yao, J. M.; Sun, B.; Woods, P. J.; Meng, J.

    2008-02-15

    The ground-state properties of the recent reported proton emitter {sup 145}Tm have been studied within the axially or triaxially deformed relativistic mean field (RMF) approaches, in which the pairing correlation is taken into account by the BCS-method with a constant pairing gap. It is found that triaxiality and pairing correlations play important roles in reproducing the experimental one proton separation energy. The single-particle level, the proton emission orbit, the deformation parameters {beta}=0.22 and {gamma}=28.98 deg. and the corresponding spectroscopic factor for {sup 145}Tm in the triaxial RMF calculation are given as well.

  4. Proton and neutron skins of light nuclei within the relativistic mean field theory

    NASA Astrophysics Data System (ADS)

    Geng, L. S.; Toki, H.; Ozawa, A.; Meng, J.

    2004-01-01

    The relativistic mean field (RMF) theory is applied to the analysis of ground-state properties of Ne, Na, Cl and Ar isotopes. In particular, we study the recently established proton skin in Ar isotopes and neutron skin in Na isotopes as a function of the difference between the proton and the neutron separation energy. We use the TMA effective interaction in the RMF Lagrangian, and describe pairing correlation by the density-independent delta-function interaction. We calculate single neutron and proton separation energies, quadrupole deformations, nuclear matter radii and differences between proton radii and neutron radii, and compare these results with the recent experimental data.

  5. La Hipotesis Funcional y la Aparicion de Sujeto no Nominal: El Espanol de Puerto Rico (The Functional Hypothesis and the Appearance of a Non-Nominative Subject: The Spanish of Puerto Rico).

    ERIC Educational Resources Information Center

    Morales, Amparo

    1997-01-01

    Discusses the Puerto Rican dialect and its peculiar placement of subject pronouns. Notes the linguistic variety in the dialect as well as its use of verbs connotating mental and communicative activity and constructions of relativity. These distinctions give rise to the functional hypothesis to account for the peculiarities of Spanish in the…

  6. Systemic Functional Linguistics and Discourse Analysis as Alternatives When Dealing with Texts (La lingüística sistémica funcional y el análisis del discurso como alternativas para trabajar con textos)

    ERIC Educational Resources Information Center

    García Montes, Paula Andrea; Sagre Barboza, Ana María; Lacharme Olascoaga, Alba Isabel

    2014-01-01

    This article presents a case study research with aims to find out which activities, methodological and textual aspects used in a reading strategies course were causing a group of students difficulties when analyzing critically written information. We conducted the study at Universidad de Córdoba (Colombia) with seventh semester students from the…

  7. Regulación del flujo sanguíneo uterino. I. Funciones de estrógeno y receptores estrogénicos α/β en el endotelio vascular uterino durante el embarazo

    PubMed Central

    Mayra, Pastore R.; Rosalina, Villalón L.; López, Gladys; Iruretagoyena, Jesús; Magness, Ronald

    2015-01-01

    Resumen El estrógeno y los receptores estrogénicos clásicos (REs), RE-α y RE-β, han demostrado ser parcialmente responsable por las adaptaciones endoteliales uterinas durante el embarazo al corto y largo plazo. Las diferencias moleculares y estructurales, junto con los diferentes efectos causados por estos receptores en las células y los tejidos, sugieren que su función varía dependiendo de la manera en la cual el estrógeno se comunica con sus receptores. En ésta revisión bibliográfica se discuten la función del estrógeno y sus receptores clásicos en las adaptaciones cardiovasculares durante el embarazo y la expresión de los Res in vivo e in vitro en el endotelio de la arteria uterina durante el ciclo ovárico y el embarazo, a la vez comparado con la expresión en endotelio arterial de tejidos reproductivos y no reproductivos. Estos temas integran el conocimiento actual de este amplio campo científico con interpretaciones e hipótesis diversas relacionadas con los efectos estrogénicos mediados bien sea por uno o los dos REs. Esta revisión también incluye la relación con las adaptaciones vasodilatadoras y angiogénicas requeridas para modular el dramático incremento fisiológico en la perfusión útero-placentaria observada durante un embarazo normal. PMID:26113750

  8. Hidden sketches by Leonardo da Vinci revealed

    NASA Astrophysics Data System (ADS)

    Dumé, Belle

    2009-02-01

    Three drawings on the back of Leonardo da Vinci's The Virgin and Child with St Anne (circa 1508) have been discovered by researchers led by Michel Menu from the Centre de Recherche et de Restauration des Musées de France (C2RMF) and the Louvre Museum in Paris.

  9. Temporal Variations of Magnetic Field Associated with Seismic Activity at Cerro Machin Volcano, Colombia

    NASA Astrophysics Data System (ADS)

    Londono, J. M.; Serna, J. P.; Guzman, J.

    2011-12-01

    A study of magnetic variations was carried out at Cerro Machin Volcano, Colombia for the period 2009 -2010, with two permanent magnetometers located at South and North of the central dome, separated about 2.5 km each other. After corrections, we found that there is no clear correlation between volcanic seismicity and temporal changes of magnetic field for each magnetometer station, if they are analyzed individually. On the contrary, when we calculated the residual Magnetic field (RMF), for each magnetometer, and then we made the subtraction between them, and plot it vs time, we found a clear correlation of changes in local magnetic field with the occurrence of volcanic seismicity (ML >1.6). We found a change in the RMF between 1584 nT and 1608 nT, each time that a volcano-tectonic earthquake occurred. The máximum lapse time between the previous change in RMF and the further occurrence of the earthquake is 24 days, with an average of 11 days. This pattern occurred more than 9 times during the studied period. Based on the results, we believed that the simple methodology proposed here, is a good tool for monitoring changes in seismicity associated with activity at Cerro Machín volcano. We suggest that the temporal changes of RMF at Cerro Machín Volcano, are associated with piezo-magnetic effects, due to changes in strain-stress inside the volcano, produced by the interaction between local faulting and magma movement.

  10. Growth of II-VI Solid Solutions in the Presence of a Rotating Magnetic Field

    NASA Technical Reports Server (NTRS)

    Gillies, D. C; Motakef, S.; Dudley, M.; Matyi, R.; Volz, H.

    1999-01-01

    The application of a rotating magnetic field (RMF)in the frequency range 60-400 Hz and field strength of the order of 2-8 mT to crystal growth has received increasing attention in recent years. To take full advantage of the control of fluid flow by the forces applied by the field, the liquid column must be electrically conducting. Also, the application of RMF to the directional solidification of a column of liquid can result in complete mixing in the resultant solid. Thus, the technique of RMF is suited to solvent zones and float zones where the composition of the liquid is more readily controlled. In the work we report on, numerical modeling has been applied to II-VI systems, particularly tellurium based traveling heater techniques (THM). Results for a spectrum of field strengths and acceleration levels will be presented. These show clearly the effects of competing buoyancy forces and electromagnetic stirring. Crystals of cadmium zinc telluride and mercury cadmium telluride have been grown terrestrially from a tellurium solvent zone. The effects of the RMF during these experiments will be demonstrated with micrographs showing etch pits, white beam x-ray synchrotron topographs and triple axis x-ray diffraction.

  11. Condensed-to-atoms hardness kernel from the response of molecular fragment approach

    NASA Astrophysics Data System (ADS)

    Miranda-Quintana, Ramón Alain

    2016-08-01

    Condensed reactivity descriptors obtained from the response of molecular fragment (RMF) approach are analyzed within the variational formulation of conceptual density functional theory. It is shown that this approach can serve as the basis of a coherent formulation of the hardness kernel.

  12. Acceptance Factors Influencing Adoption of National Institute of Standards and Technology Information Security Standards: A Quantitative Study

    ERIC Educational Resources Information Center

    Kiriakou, Charles M.

    2012-01-01

    Adoption of a comprehensive information security governance model and security controls is the best option organizations may have to protect their information assets and comply with regulatory requirements. Understanding acceptance factors of the National Institute of Standards and Technology (NIST) Risk Management Framework (RMF) comprehensive…

  13. Adaptation in tunably rugged fitness landscapes: the rough Mount Fuji model.

    PubMed

    Neidhart, Johannes; Szendro, Ivan G; Krug, Joachim

    2014-10-01

    Much of the current theory of adaptation is based on Gillespie's mutational landscape model (MLM), which assumes that the fitness values of genotypes linked by single mutational steps are independent random variables. On the other hand, a growing body of empirical evidence shows that real fitness landscapes, while possessing a considerable amount of ruggedness, are smoother than predicted by the MLM. In the present article we propose and analyze a simple fitness landscape model with tunable ruggedness based on the rough Mount Fuji (RMF) model originally introduced by Aita et al. in the context of protein evolution. We provide a comprehensive collection of results pertaining to the topographical structure of RMF landscapes, including explicit formulas for the expected number of local fitness maxima, the location of the global peak, and the fitness correlation function. The statistics of single and multiple adaptive steps on the RMF landscape are explored mainly through simulations, and the results are compared to the known behavior in the MLM model. Finally, we show that the RMF model can explain the large number of second-step mutations observed on a highly fit first-step background in a recent evolution experiment with a microvirid bacteriophage. PMID:25123507

  14. Adaptation in Tunably Rugged Fitness Landscapes: The Rough Mount Fuji Model

    PubMed Central

    Neidhart, Johannes; Szendro, Ivan G.; Krug, Joachim

    2014-01-01

    Much of the current theory of adaptation is based on Gillespie’s mutational landscape model (MLM), which assumes that the fitness values of genotypes linked by single mutational steps are independent random variables. On the other hand, a growing body of empirical evidence shows that real fitness landscapes, while possessing a considerable amount of ruggedness, are smoother than predicted by the MLM. In the present article we propose and analyze a simple fitness landscape model with tunable ruggedness based on the rough Mount Fuji (RMF) model originally introduced by Aita et al. in the context of protein evolution. We provide a comprehensive collection of results pertaining to the topographical structure of RMF landscapes, including explicit formulas for the expected number of local fitness maxima, the location of the global peak, and the fitness correlation function. The statistics of single and multiple adaptive steps on the RMF landscape are explored mainly through simulations, and the results are compared to the known behavior in the MLM model. Finally, we show that the RMF model can explain the large number of second-step mutations observed on a highly fit first-step background in a recent evolution experiment with a microvirid bacteriophage. PMID:25123507

  15. Residual mode filters and adaptive control in large space structures

    NASA Technical Reports Server (NTRS)

    Davidson, Roger A.; Balas, Mark J.

    1989-01-01

    One of the most difficult problems in controlling large systems and structures is compensating for the destructive interaction which can occur between the reduced-order model (ROM) of the plant, which is used by the controller, and the unmodeled dynamics of the plant, often called the residual modes. The problem is more significant in the case of large space structures because their naturally light damping and high performance requirements lead to more frequent, destructive residual mode interaction (RMI). Using the design/compensation technique of residual mode filters (RMF's), effective compensation of RMI can be accomplished in a straightforward manner when using linear controllers. The use of RMF's has been shown to be effective for a variety of large structures, including a space-based laser and infinite dimensional systems. However, the dynamics of space structures is often uncertain and may even change over time due to on-orbit erosion from space debris and corrosive chemicals in the upper atmosphere. In this case, adaptive control can be extremely beneficial in meeting the performance requirements of the structure. Adaptive control for large structures is also based on ROM's and so destructive RMI may occur. Unfortunately, adaptive control is inherently nonlinear, and therefore the known results of RMF's cannot be applied. The purpose is to present the results of new research showing the effects of RMI when using adaptive control and the work which will hopefully lead to RMF compensation of this problem.

  16. SNAP/SHOT Your Ability to Support That Next Application.

    ERIC Educational Resources Information Center

    Jones, Ernest L.

    SNAP/SHOT (System Network Analysis Program-Simulated Host Overview Technique) is a discrete simulation of a network and/or host model available through IBM at the Raleigh System Center. The simulator provides an analysis of a total IBM Communications System. Input data must be obtained from RMF, SMF, and the CICS Analyzer to determine the existing…

  17. Radial current density effects on rotating magnetic field current drive in field-reversed configurations

    SciTech Connect

    Clemente, R. A.; Gilli, M.; Farengo, R.

    2008-10-15

    Steady state solutions, suitable for field-reversed configurations (FRCs) sustained by rotating magnetic fields (RMFs) are obtained by properly including three-dimensional effects, in the limit of large FRC elongation, and the radial component of Ohm's law. The steady electrostatic potential, necessary to satisfy Ohm's law, is considered to be a surface function. The problem is analyzed at the midplane of the configuration and it is reduced to the solution of two coupled nonlinear differential equations for the real and imaginary parts of the phasor associated to the longitudinal component of the vector potential. Additional constraints are obtained by requesting that the steady radial current density and poloidal magnetic flux vanish at the plasma boundary which is set at the time-averaged separatrix. The results are presented in terms of the degree of synchronism of the electrons with the RMF and compared with those obtained when radial current effects are neglected. Three important differences are observed when compared with the case without radial current density. First, at low penetration of the RMF into the plasma there is a significant increase in the driven azimuthal current. Second, the RMF amplitude necessary to access the high synchronism regime, starting from low synchronism, is larger and the difference appears to increase as the separatrix to classical skin depth ratio increases. Third, the minimum RMF amplitude necessary to sustain almost full synchronism is reduced.

  18. The structural and decay properties of Francium isotopes

    NASA Astrophysics Data System (ADS)

    Bhuyan, M.; Mahapatro, S.; Singh, S. K.; Patra, S. K.

    2015-04-01

    We study the bulk properties such as binding energy (BE), root-mean-square (RMS) charge radius, quadrupole deformation etc. for Francium (Fr) isotopes having mass number A = 180-240 within the framework of relativistic mean field (RMF) theory. Systematic comparisons are made between the calculated results from RMF theory, Finite Range Droplet Model (FRDM) and the experimental data. Most of the nuclei in the isotopic chain shows prolate configuration in their ground state. The α-decay properties like α-decay energy and the decay half-life are also estimated for three different chains of 198Fr, 199Fr and 200Fr. The calculation for the decay half-life are carried out by taking two different empirical formulae and the results are compared with the experimental data.

  19. Measurements accounting for the impediment of ion spin-up in rotating magnetic field driven field reversed configurations

    NASA Astrophysics Data System (ADS)

    Deards, C. L.; Hoffman, A. L.; Steinhauer, L. C.

    2011-11-01

    Improved vacuum hygiene, wall conditioning, and reduced recycling in the rotating magnetic field (RMF) driven translation, confinement, and sustainment-upgrade (TCSU) field reversed configuration experiment have made possible a more accurate assessment of the forces affecting ion spin-up. This issue is critical in plasmas sustained by RMFs, such as TCSU since ion spin-up can substantially reduce or cancel the RMF current drive effect. Several diagnostics are brought to bear, including a 3-axis translatable magnetic probe allowing the first experimental measurement of the end shorting effect. These results show that the ion rotation is determined by a balance between electron-ion friction, the end shorting effect, and ion drag against neutrals.

  20. Covariant density functional theory: The role of the pion

    SciTech Connect

    Lalazissis, G. A.; Karatzikos, S.; Serra, M.; Otsuka, T.; Ring, P.

    2009-10-15

    We investigate the role of the pion in covariant density functional theory. Starting from conventional relativistic mean field (RMF) theory with a nonlinear coupling of the {sigma} meson and without exchange terms we add pions with a pseudovector coupling to the nucleons in relativistic Hartree-Fock approximation. In order to take into account the change of the pion field in the nuclear medium the effective coupling constant of the pion is treated as a free parameter. It is found that the inclusion of the pion to this sort of density functionals does not destroy the overall description of the bulk properties by RMF. On the other hand, the noncentral contribution of the pion (tensor coupling) does have effects on single particle energies and on binding energies of certain nuclei.

  1. Dynamic spin-flip shot noise of mesoscopic transport through a toroidal carbon nanotube

    NASA Astrophysics Data System (ADS)

    Zhao, H. K.; Zhang, J.; Wang, J.

    2015-01-01

    The shot noise in a toroidal carbon nanotube (TCN) interferometer under the perturbation of a rotating magnetic field (RMF) has been investigated. A general shot noise formula has been derived by calculating the current correlation. It was found that photon absorption and emission induce novel features of dynamic shot noise. The oscillatory behavior of shot noise and Fano factor vary with the Aharonov-Bohm (AB) magnetic flux, and they are sensitively dependent on the Zeeman energy, frequency of RMF, and source-drain bias. By adjusting the Zeeman energy, the AB oscillation structures of shot noise and Fano factor show valley-to-peak transformation. The shot noise increases nonlinearly with increasing the Zeeman energy and photon energy. The enhancement and asymmetry of shot noise can be attributed to the spin-flip effect.

  2. Single-core magnetic markers in rotating magnetic field based homogeneous bioassays and the law of mass action

    NASA Astrophysics Data System (ADS)

    Dieckhoff, Jan; Schrittwieser, Stefan; Schotter, Joerg; Remmer, Hilke; Schilling, Meinhard; Ludwig, Frank

    2015-04-01

    In this work, we report on the effect of the magnetic nanoparticle (MNP) concentration on the quantitative detection of proteins in solution with a rotating magnetic field (RMF) based homogeneous bioassay. Here, the phase lag between 30 nm iron oxide single-core particles and the RMF is analyzed with a fluxgate-based measurement system. As a test analyte anti-human IgG is applied which binds to the protein G functionalized MNP shell and causes a change of the phase lag. The measured phase lag changes for a fixed MNP and a varying analyte concentration are modeled with logistic functions. A change of the MNP concentration results in a nonlinear shift of the logistic function with the analyte concentration. This effect results from the law of mass action. Furthermore, the bioassay results are used to determine the association constant of the binding reaction.

  3. Construction of the PFRC-2 Device

    NASA Astrophysics Data System (ADS)

    Cohen, S. A.; Berlinger, B.; Brooks, A.; Brunkhorst, C.; Edwards, M.; Gumbas, J.; Myers, C.

    2011-10-01

    Upgrades to the PFRC device are being made, under an ARRA grant, to enable exploration of FRC plasmas heated by odd-parity rotating magnetic fields (RMF) to keV electron and ion temperatures. The new 84-cm-long, 22.7-cm-ID vacuum vessel is made of polycarbonate, with 87 penetrations for diagnostics, feedthroughs, and pumps. Eight internal high-temperature-superconductor flux conservers with BN shields are installed to allow extension of the plasma duration to over 0.1 s. The RMF power capability has been increased from 20 to 200 kW of 0.1 s duration. PFRC-2 operations are scheduled to begin in December 2011. Supported by USDOE contract No. DE-AC02-76-CHO-3073.

  4. Superdeformation of Ar hypernuclei

    NASA Astrophysics Data System (ADS)

    Isaka, Masahiro; Kimura, Masaaki; Hiyama, Emiko; Sagawa, Hiroyuki

    2015-10-01

    We investigate the differences in the Λ separation energies (S_Λ ) of the ground and superdeformed (SD) states in {}^{37}_Λ Ar, ^{39}_Λ Ar, and ^{41}_Λ Ar within the framework of antisymmetrized molecular dynamics (AMD). In this study, we find that the calculated S_Λ values in the SD states are much smaller than those in the ground states, unlike the result using the relativistic mean-field (RMF) calculation [B.-N. Lu et al., Phys. Rev. C, 89, 044307 (2014)]. One of the reasons for this difference between the present work and the RMF calculation is the difference in the density profile of the SD states in the core nuclei. We also find that the property of the Λ N odd-parity interaction affects the S_Λ trend between the ground and SD states.

  5. Measurements accounting for the impediment of ion spin-up in rotating magnetic field driven field reversed configurations

    SciTech Connect

    Deards, C. L.; Hoffman, A. L.; Steinhauer, L. C.

    2011-11-15

    Improved vacuum hygiene, wall conditioning, and reduced recycling in the rotating magnetic field (RMF) driven translation, confinement, and sustainment-upgrade (TCSU) field reversed configuration experiment have made possible a more accurate assessment of the forces affecting ion spin-up. This issue is critical in plasmas sustained by RMFs, such as TCSU since ion spin-up can substantially reduce or cancel the RMF current drive effect. Several diagnostics are brought to bear, including a 3-axis translatable magnetic probe allowing the first experimental measurement of the end shorting effect. These results show that the ion rotation is determined by a balance between electron-ion friction, the end shorting effect, and ion drag against neutrals.

  6. Green's Function of the Dirac Equation with Complex Energy and Non-singular Central Nuclear Potential

    SciTech Connect

    Svinarenko, A. A.; Loboda, A. V.; Sukharev, D. E.; Dubrovskaya, Yu. V.; Mudraya, N. V.; Serga, I. N.; Glushkov, A. V.

    2010-05-04

    We report the further development of an effective approach to construction of the electron Green's function (GF) for the Dirac equation with a complex energy and non-singular central nuclear potential. The nuclear charge distribution and the corresponding nuclear potential are received within the relativistic mean field (RMF) model. The Green's function is usually represented as a combination of two fundamental solutions of the Dirac equation. In the numerical procedure we use the Ivanov-Ivanova effective numerical algorithm and reduce a definition of the Dirac equation fundamental solutions to solving the system of differential equations, which includes the differential equations for the RMF nuclear potential too. As an application, we estimate the self-energy shift correction to atomic levels energies within the Mohr covariant procedure and presented GF approach and calculate the transitions energies for some heavy Li-like multi-charged ions within the QED many-body perturbation theory formalism.

  7. Relativistic impulse approximation analysis of elastic proton scattering from He isotopes

    NASA Astrophysics Data System (ADS)

    Kaki, Kaori

    2014-01-01

    Recent relativistic mean field (RMF) calculations have provided nuclear distributions of some isotopes whose mass numbers are much larger than atomic numbers. For helium isotopes, the RMF calculation seems to be inappropriate because of the small mass numbers; however, applicable results are obtained for 6,8He nuclei. The author calculates observables of proton elastic scattering from the helium isotopes and discusses relations between observables and nuclear distributions of the isotopes by comparison of the calculated results with experimental data. The calculations are based on relativistic impulse approximation (RIA) at incident proton energy: 71 MeV for 4,6,8He, 300 and 500 MeV for 4He, and 0.7 GeV for 6He. Scattering observables are predicted for 6,8He at 200 MeV.

  8. Possibility of an s-wave pion condensate in neutron stars reexamined

    SciTech Connect

    Ohnishi, A.; Jido, D.; Sekihara, T.; Tsubakihara, K.

    2009-09-15

    We examine possibilities of pion condensation with zero momentum (s-wave condensation) in neutron stars by using the pion-nucleus optical potential U and the relativistic mean field (RMF) models. We use low-density phenomenological optical potentials parametrized to fit deeply bound pionic atoms or pion-nucleus elastic scatterings. The proton fraction (Y{sub p}) and electron chemical potential ({mu}{sub e}) in neutron star matter are evaluated in RMF models. We find that the s-wave pion condensation hardly takes place in neutron stars and especially has no chance if hyperons appear in neutron star matter and/or the b{sub 1} parameter in U has density dependence.

  9. Investigating a suitable equation of state for an infinite system of nucleons

    NASA Astrophysics Data System (ADS)

    Zoghi-Foumani, Niloufar; Shojaei, Mohammad Reza

    2016-08-01

    In this paper, the average energy variation with respect to the density of a system of nucleons is theoretically studied. A new formula is proposed for the nuclear equation of state. This formula is related to an infinite system of protons and neutrons with relatively small thermal excitation. It is shown that the presented formulation for the nuclear equation of state reproduces the results obtained in the Skyrme-Hartree-Fock (SHF) and Relativistic Mean-Field (RMF) models of nuclear matter. It should be realized that the consistency of the obtained results for nuclear matter with the predictions of the well-known SHF and RMF models for symmetric and asymmetric system of nucleons indicates the reliability of this formulation for various types of nuclear matter in large scales such as neutron stars.

  10. Effects of NN potentials on p Nuclides in the A ˜100-120 region

    NASA Astrophysics Data System (ADS)

    Lahiri, C.; Biswal, S. K.; Patra, S. K.

    2016-02-01

    Microscopic optical potentials for low-energy proton reactions have been obtained by folding density dependent M3Y (DDM3Y) interaction derived from nuclear matter calculation with densities from mean field approach to study astrophysically important proton rich nuclei in mass 100-120 region. We compare S factors for low-energy (p,γ) reactions with available experimental data and further calculate astrophysical reaction rates for (p,γ) and (p,n) reactions. Again, we choose some nonlinear R3Y (NR3Y) interactions from relativistic mean field (RMF) calculation and folded them with corresponding RMF densities to reproduce experimental S-factor values in this mass region. Finally, the effect of nonlinearity on our result is discussed.

  11. Convective Power Loss Measurements in a Field Reversed Configuration with Rotating Magnetic Field Current Drive

    NASA Astrophysics Data System (ADS)

    Melnik, Paul

    The Translation, Confinement, and Sustainment Upgrade (TCSU) experiment achieves direct formation and sustainment of a field reversed configuration (FRC) plasma through rotating magnetic fields (RMF). The pre-ionized gas necessary for FRC formation is supplied by a magnetized cascade arc source that has been developed for TCSU. To ensure ideal FRC performance, the condition of the vacuum chamber prior to RMF start-up has been characterized with the use of a fast response ion gauge. A circuit capable of gating the puff valves with initial high voltage for quick response and then indefinite operational voltage was also designed. A fully translatable combination Langmuir / Mach probe was also built to measure the electron temperature, electron density, and ion velocity of the FRC. These measurements were also successfully completed in the FRC exhaust jets allowing for an accurate analysis of the FRC power loss through convection.

  12. Hubble, bubble, toil and trouble: A reduced-order model based saga of the Hubble Space Telescope. [pointing control performance

    NASA Technical Reports Server (NTRS)

    Balas, Mark; Robertson, L. R.; Lee, Yung Jae; Mohl, James; Garzella, Rebecca

    1993-01-01

    Low-order control of the Hubble Space Telescope (HST) to improve pointing performance in the presence of flexible solar array disturbances is demonstarted in this paper. Our controller is a disturbance accommodating controller (DAC) based on a reduced-order model (ROM) controller with a disturbance estimator and a residual mode filter (RMF). We achieve the performance goals with a very low-order multichannel controller as compared to the various Solar Array Gain Augmentation (SAGA) schemes used at present.

  13. Superheavy nuclei and fission barriers

    NASA Astrophysics Data System (ADS)

    Lu, Bing-Nan; Zhao, Jie; Zhao, En-Guang; Zhou, Shan-Gui

    In this chapter, we will present relativistic mean field (RMF) description of heavy and superheavy nuclei (SHN). We will discuss the shell structure and magic numbers in the mass region of SHN, binding energies and α decay Q values, shapes of ground states and potential energy surfaces and fission barriers. We particularly focus on the multidimensionally-constrained covariant density functional theories (CDFT) and the applications of CDFT to the study of exotic nuclear shapes and fission barriers.

  14. Rotating magnetic quadrupole current drive for field-reversed configurations

    SciTech Connect

    Milroy, Richard D.; Guo, H.Y.

    2005-07-15

    In the translation, confinement, and sustainment experiment [A. L. Hoffman, H. Y. Guo, J. T. Slough, S. J. Tobin, L. S. Schrank, W. A. Reass, and G. A. Wurden, Fusion Sci. Technol. 41, 92 (2002)], field-reversed configurations (FRCs) are created and sustained using a rotating magnetic field (RMF). The RMF is usually in the form of a rotating dipole, which in vacuum penetrates uniformly to the axis of symmetry. However, plasma conditions in the FRC normally adjust so that the RMF only partially penetrates the plasma column. We have investigated the possibility of using a rotating quadrupole rather than a rotating dipole magnetic field. The vacuum field from a quadrupole is proportional to radius and cannot penetrate to the axis of symmetry; however, this is not a disadvantage if the current drive is confined to the outer region of the FRC. It was found that the quadrupole drive efficiency is comparable to that of a dipole, but the rotating dipole is more effective at stabilizing the n=2 rotational instability. A strong internal oscillation in B{sub {theta}} is often observed in FRCs sustained by a quadrupole field. The spectral content of the signals indicates that an internal n=1 magnetic structure forms and corotates with the electrons. Similar but much lower amplitude structures can form when a rotating dipole is employed (edge-driven mode)

  15. Estimation of individual dust exposure by magnetopneumography in stainless steel production.

    PubMed

    Huvinen, M; Oksanen, L; Kalliomäki, K; Kalliomäki, P L; Moilanen, M

    1997-06-20

    The objectives of the study were to measure the magnetic dust lung burden of workers in stainless steel production by magnetopneumography (MPG) and to investigate the relationship of the results with air-borne concentrations of dust, total and hexavalent chromium as well as urinary excretion of chromium. There were 128 workers from the chromite mine, sintering plant, ferrochrome smelter, stainless steel smelting shop, cold rolling mill and welding shop in the exposed groups and five persons from the office staff in the control group. The remanent magnetic field (RMF) in the lungs was slightly elevated among workers in the ferrochromium and steel smelting shops; the levels were, however, lower than those reported for welders earlier and those observed in the welding/repair shop. Workers in the mine, concentrator and sintering plants and in the cold rolling mill exhibited remanent magnetic fields comparable to the referents. There was a relationship between the RMF and the actual urinary chromium concentration. Miners and concentrator and sintering plant workers showed retarded relaxation rate (ReR) of the remanent magnetic field. However, the RMF of the first two of these groups were low (< 0.1 nT) and this made it difficult to measure the ReR accurately. The duration of exposure correlated weakly but significantly with the relaxation rate, while smoking was not related to it. PMID:9200856

  16. Probe measurements of the three-dimensional magnetic field structure in a rotating magnetic field sustained field-reversed configuration

    SciTech Connect

    Velas, K. M.; Milroy, R. D.

    2014-01-15

    A translatable three-axis probe was constructed and installed on the translation, confinement, and sustainment upgrade (TCSU) experiment. With ninety windings, the probe can simultaneously measure B{sub r}, B{sub θ}, and B{sub z} at 30 radial positions, and can be placed at any desired axial position within the field reversed configuration (FRC) confinement chamber. Positioning the probe at multiple axial positions and taking multiple repeatable shots allows for a full r-z map of the magnetic field. Measurements were made for odd-parity rotating magnetic field (RMF) antennas and even-parity RMF. The steady state data from applying a 10 kHz low pass filter used in conjunction with data at the RMF frequency yields a map of the full 3D rotating field structure. Comparisons will be made to the 3D magnetic structure predicted by NIMROD simulations, with parameters adjusted to match that of the TCSU experiments. The probe provides sufficient data to utilize a Maxwell stress tensor approach to directly measure the torque applied to the FRC's electrons, which combined with a resistive torque model, yields an estimate of the average FRC resistivity.

  17. A stochastic analysis of the influence of soil and climatic variability on the estimate of pesticide ground water polution potential

    NASA Astrophysics Data System (ADS)

    Jury, William A.; Gruber, Joachim

    1989-12-01

    Soil and climatic variability contribute in an unknown manner to the leaching of pesticides below the surface soil zone where degradation occurs at maximum levels. In this paper we couple the climatic variability model of Eagleson (1978) to the soil variability transport model of Jury (1982) to produce a probability density distribution of residual mass fraction (RMF) remaining after leaching below the surface degradation zone. Estimates of the RMF distribution are shown to be much more sensitive to soil variability than climatic variability, except when the residence time of the chemical is shorter than one year. When soil variability dominates climatic variability, the applied water distribution may be replaced by a constant average water application rate without serious error. Simulations of leaching are run with 10 pesticides in two climates and in two representative soil types with a range of soil variability. Variability in soil or climate act to produce a nonnegligible probability of survival of a small value of residual mass even for relatively immobile compounds which are predicted to degrade completely by a simple model which neglects variability. However, the simpler model may still be useful for screening pesticides for groundwater pollution potential if somewhat larger residual masses of a given compound are tolerated. Monte Carlo simulations of the RMF distribution agreed well with model predictions over a wide range of pesticide properties.

  18. Separating Effect of a Novel Combined Magnetic Field on Inclusions in Molten Aluminum Alloy

    NASA Astrophysics Data System (ADS)

    He, Yanjie; Li, Qiulin; Liu, Wei

    2012-10-01

    The feasibility and effectiveness of a novel combined magnetic field (CMF) on the removal of inclusions with a density smaller than the surrounding melt were investigated. The experiment of the separating effect of CMF was conducted on a laboratory-scale apparatus by the simultaneous application of a rotating magnetic field (RMF) and a downward traveling magnetic field (TMF). Primary silicon particles precipitating from the solidification process of Al-Si-Cu alloy were regarded as the inclusions in a molten aluminum alloy. It was found that a CMF consisting of both a RMF and a downward TMF was able to separate silicon particles from the molten Al-Si-Cu alloy by making these particles migrate vertically toward the upper part of the samples. Compared with downward TMF or RMF, CMF improved the separating effectiveness substantially. It was proposed that this type of CMF was approved to be highly effective at eliminating the inclusions with a density smaller than the surrounding molten alloy. A tentative mechanism for the high separating effect of CMF was discussed.

  19. Separation and purification of Si from solidification of hypereutectic Al-Si melt under rotating magnetic field

    NASA Astrophysics Data System (ADS)

    Jie, J. C.; Zou, Q. C.; Wang, H. W.; Sun, J. L.; Lu, Y. P.; Wang, T. M.; Li, T. J.

    2014-08-01

    A low-cost and high-efficiency method to purify Si directly from cheap MG-Si at low temperature was proposed and demonstrated in this paper, which used power frequency rotating magnetic field (RMF) to separate the primary Si from a hypereutectic Al-Si alloy and was followed by the acid peeling. The separation mechanism was based on the flow characteristic of melt under RMF and the cooling condition of the liquid metal. A Si-rich layer with Si content of 65-59 wt% was formed in the periphery of alloy, while the inner microstructure of the alloy was mainly the Al-Si eutectic structure. The refined silicon was collected after aqua regia leaching, and had much fewer typical impurities (Fe, Ti, Ca, B, P) than those in MG-Si, and the metallic impurities besides Al had removal fraction higher than 98%, which is mainly ascribed to the segregation effect of Al-30Si alloy during solidification under RMF.

  20. Adaptive Control of Flexible Structures Using Residual Mode Filters

    NASA Technical Reports Server (NTRS)

    Balas, Mark J.; Frost, Susan

    2010-01-01

    Flexible structures containing a large number of modes can benefit from adaptive control techniques which are well suited to applications that have unknown modeling parameters and poorly known operating conditions. In this paper, we focus on a direct adaptive control approach that has been extended to handle adaptive rejection of persistent disturbances. We extend our adaptive control theory to accommodate troublesome modal subsystems of a plant that might inhibit the adaptive controller. In some cases the plant does not satisfy the requirements of Almost Strict Positive Realness. Instead, there maybe be a modal subsystem that inhibits this property. This section will present new results for our adaptive control theory. We will modify the adaptive controller with a Residual Mode Filter (RMF) to compensate for the troublesome modal subsystem, or the Q modes. Here we present the theory for adaptive controllers modified by RMFs, with attention to the issue of disturbances propagating through the Q modes. We apply the theoretical results to a flexible structure example to illustrate the behavior with and without the residual mode filter. We have proposed a modified adaptive controller with a residual mode filter. The RMF is used to accommodate troublesome modes in the system that might otherwise inhibit the adaptive controller, in particular the ASPR condition. This new theory accounts for leakage of the disturbance term into the Q modes. A simple three-mode example shows that the RMF can restore stability to an otherwise unstable adaptively controlled system. This is done without modifying the adaptive controller design.

  1. COMPENDIUM OF COMPLETED TESTING IN SUPPORT OF ROTARY MICROFILTRATION AT SAVANNAH RIVER SITE AND HANFORD

    SciTech Connect

    HUBER HJ

    2011-05-24

    This report presents a chronological summary of previous technology development efforts concerning the rotary microfiltration (RMF) unit from SpinTek{trademark}. Rotary microfiltration has been developed for high radiation application over the last decades as one of the optional filtration techniques for supplemental treatment. Supplemental treatment includes a near- or in-tank solids separation and subsequent cesium removal unit, followed by an immobilization technique; this includes options such as steam reforming, bulk vitrification or cast stone (grout). The main difference between RMF and standard cross flow filtration (CFF) is the disconnection of filtrate flux from feed velocity; i.e., filtrate flux is only dependent on transmembrane pressure, filter fouling and temperature. These efforts have been supported by the U.S. Department of Energy (DOE), Office of Cleanup Technologies since the 1990s by their Environmental Management Program (currently EM-31). In order to appropriately address future testing needs, a compilation of the relevant previous testing reports was essential. This compendium does not intend to cover all of the presentations/reports that were produced over the last decades but focuses on those of relevance for developing an RMF unit fit for deployment at the Hanford site. The report is split into three parts: (1) an introductory overview, (2) Figure 1 graphically covering the main development steps and its key players and (3) a more detailed table of the citations and brief descriptions of results and recommendations.

  2. High resource-capture and -use efficiency, and effective antioxidant protection contribute to the invasiveness of Alnus formosana plants.

    PubMed

    Liu, Shiliang; Luo, Yiming; Yang, Rongjie; He, Chengxiang; Cheng, Qingsu; Tao, Jianjun; Ren, Bo; Wang, Maohua; Ma, Mingdong

    2015-11-01

    To investigate the traits contributing to the invasiveness of Alnus formosana and the mechanisms underlying its invasiveness, we compared A. formosana with its native congener (Alnus cremastogyne) under three light treatments (13%, 56%, and 100%). The consistently higher plant height, total leaf area, light-saturated photosynthetic rate (A(max)), light saturation point (LSP), light compensation point (LCP), respiration efficiency (RE), and non-photochemical quenching coefficient (NPQ) but lower root mass fraction (RMF) and specific leaf area (SLA) of the invader than of its native congener contributed to the higher RGR and total biomass of A. formosana across light regimes. The total biomass and RGR of the invader increased markedly with increased RMF, A(max), LSP, LCP, RE, stomatal conductance (G(s)) and total leaf area. Furthermore, compared with the native species, the higher plasticity index in plant height, RMF, leaf mass fraction (LMF), SMF, SLA, A(max) and dark respiration rate (R(d)) within the range of total light contributed to the higher performance of the invader. In addition, the activities of antioxidant enzymes were higher in the invader compared to the native, contributing to its invasion success under high/low light via photoprotection. With a decrease in light level, superoxide dismutase (SOD) and catalase (CAT) activities increased significantly, whereas total carotenoid (Car) and total chlorophyll (Chl) decreased; ascorbate peroxidase (APX) and glutathione reductase (GR) activities remained unchanged. These responses may help the invader to spread and invade a wide range of habitats and form dense monocultures, displacing native plant species. The results suggest that both resource capture-related traits (morphological and photosynthetic) and adaptation-related traits (antioxidant protection) contribute to the competitive advantage of the invader. PMID:26433486

  3. Spins and parities of the odd-A P isotopes within a relativistic mean-field model and elastic magnetic electron-scattering theory

    NASA Astrophysics Data System (ADS)

    Wang, Zaijun; Ren, Zhongzhou; Dong, Tiekuang; Xu, Chang

    2014-08-01

    The ground-state spins and parities of the odd-A phosphorus isotopes 25-47P are studied with the relativistic mean-field (RMF) model and relativistic elastic magnetic electron-scattering theory (REMES). Results of the RMF model with the NL-SH, TM2, and NL3 parameters show that the 2s1/2 and 1d3/2 proton level inversion may occur for the neutron-rich isotopes 37-47P, and, consequently, the possible spin-parity values of 37-47P may be 3/2+, which, except for P47, differs from those given by the NUBASE2012 nuclear data table by Audi et al. Calculations of the elastic magnetic electron scattering of 37-47P with the single valence proton in the 2s1/2 and 1d3/2 state show that the form factors have significant differences. The results imply that elastic magnetic electron scattering can be a possible way to study the 2s1/2 and 1d3/2 level inversion and the spin-parity values of 37-47P. The results can also provide new tests as to what extent the RMF model, along with its various parameter sets, is valid for describing the nuclear structures. In addition, the contributions of the upper and lower components of the Dirac four-spinors to the form factors and the isotopic shifts of the magnetic form factors are discussed.

  4. Second relativistic mean field and virial equation of state for astrophysical simulations

    SciTech Connect

    Shen, G.; Horowitz, C. J.; O'Connor, E.

    2011-06-15

    We generate a second equation of state (EOS) of nuclear matter for a wide range of temperatures, densities, and proton fractions for use in supernovae, neutron star mergers, and black hole formation simulations. We employ full relativistic mean field (RMF) calculations for matter at intermediate density and high density, and the virial expansion of a nonideal gas for matter at low density. For this EOS we use the RMF effective interaction FSUGold, whereas our earlier EOS was based on the RMF effective interaction NL3. The FSUGold interaction has a lower pressure at high densities compared to the NL3 interaction. We calculate the resulting EOS at over 100 000 grid points in the temperature range T=0 to 80 MeV, the density range n{sub B}=10{sup -8} to 1.6 fm{sup -3}, and the proton fraction range Y{sub p}=0 to 0.56. We then interpolate these data points using a suitable scheme to generate a thermodynamically consistent equation of state table on a finer grid. We discuss differences between this EOS, our NL3-based EOS, and previous EOSs by Lattimer-Swesty and H. Shen et al. for the thermodynamic properties, composition, and neutron star structure. The original FSUGold interaction produces an EOS, which we call FSU1.7, that has a maximum neutron star mass of 1.7 solar masses. A modification in the high-density EOS is introduced to increase the maximum neutron star mass to 2.1 solar masses and results in a slightly different EOS that we call FSU2.1. The EOS tables for FSU1.7 and FSU2.1 are available for download.

  5. NEW EQUATIONS OF STATE IN SIMULATIONS OF CORE-COLLAPSE SUPERNOVAE

    SciTech Connect

    Hempel, M.; Liebendoerfer, M.; Fischer, T.; Schaffner-Bielich, J.

    2012-03-20

    We discuss three new equations of state (EOS) in core-collapse supernova simulations. The new EOS are based on the nuclear statistical equilibrium model of Hempel and Schaffner-Bielich (HS), which includes excluded volume effects and relativistic mean-field (RMF) interactions. We consider the RMF parameterizations TM1, TMA, and FSUgold. These EOS are implemented into our spherically symmetric core-collapse supernova model, which is based on general relativistic radiation hydrodynamics and three-flavor Boltzmann neutrino transport. The results obtained for the new EOS are compared with the widely used EOS of H. Shen et al. and Lattimer and Swesty. The systematic comparison shows that the model description of inhomogeneous nuclear matter is as important as the parameterization of the nuclear interactions for the supernova dynamics and the neutrino signal. Furthermore, several new aspects of nuclear physics are investigated: the HS EOS contains distributions of nuclei, including nuclear shell effects. The appearance of light nuclei, e.g., deuterium and tritium, is also explored, which can become as abundant as alphas and free protons. In addition, we investigate the black hole formation in failed core-collapse supernovae, which is mainly determined by the high-density EOS. We find that temperature effects lead to a systematically faster collapse for the non-relativistic LS EOS in comparison with the RMF EOS. We deduce a new correlation for the time until black hole formation, which allows the determination of the maximum mass of proto-neutron stars, if the neutrino signal from such a failed supernova would be measured in the future. This would give a constraint for the nuclear EOS at finite entropy, complementary to observations of cold neutron stars.

  6. Shell closures, loosely bound structures, and halos in exotic nuclei

    SciTech Connect

    Saxena, G.; Singh, D.

    2013-04-15

    Inspired by the recent experiments indicating doubly magic nuclei that lie near the drip-line and encouraged by the success of our relativistic mean-field (RMF) plus state-dependent BCS approach to the description of the ground-state properties of drip-line nuclei, we develop this approach further, across the entire periodic table, to explore magic nuclei, loosely bound structures, and halo formation in exotic nuclei. In our RMF+BCS approach, the single-particle continuum corresponding to the RMF is replaced by a set of discrete positive-energy states for the calculations of pairing energy. Detailed analysis of the single-particle spectrum, pairing energies, and densities of the nuclei predict the unusual proton shell closures at proton numbers Z = 6, 14, 16, 34, and unusual neutron shell closures at neutron numbers N = 6, 14, 16, 34, 40, 70, 112. Further, in several nuclei like the neutron-rich isotopes of Ca, Zr, Mo, etc., the gradual filling of lowlying single-particle resonant state together with weakly bound single-particle states lying close to the continuum threshold helps accommodate more neutrons but with an extremely small increase in the binding energy. This gives rise to the occurrence of loosely bound systems of neutron-rich nuclei with a large neutron-to-proton ratio. In general, the halo-like formation, irrespective of the existence of any resonant state, is seen to be due to the large spatial extension of the wave functions for the weakly bound single-particle states with low orbital angular momentum having very small or no centrifugal barriers.

  7. Influence of rotating magnetic fields on THM growth of CdZnTe crystals under microgravity and ground conditions

    NASA Astrophysics Data System (ADS)

    Stelian, Carmen; Duffar, Thierry

    2015-11-01

    The influence of rotating magnetic fields (RMF) on species transport and interface stability during the growth of Cd0.96Zn0.04Te:In crystals by using the traveling heater method (THM), under microgravity and terrestrial conditions, is numerically investigated. The numerical results are compared to ground and space experiments. The modeling of THM under ground conditions shows very deleterious effects of the natural convection on the morphological stability of the growth interface. The vertical flow transports the liquid of low Te concentration from the dissolution interface to the growth interface, which is consequently destabilized. The suppression of this flow, in low-gravity conditions, results in higher morphological stability of the growth interface. Application of RMF induces a two flow cell pattern, which has a destabilizing effect on the growth interface. Simulations performed by varying the magnetic field induction in the range of 1 - 3 mT show optimal conditions for the growth with a stable interface at low strength of the magnetic field (B = 1 mT). Computations of indium distribution show a better homogeneity of crystals grown under purely diffusive conditions. Rotating magnetic fields of B = 1 mT induce low intensity convection, which generates concentration gradients near the growth interface. These numerical results are in agreement with experiments performed during the FOTON M4 space mission, showing good structural quality of Cd0.96Zn0.04Te crystals grown at very low gravity level. Applying low intensity rotating magnetic fields in ground experiments has no significant influence on the flow pattern and solute distribution. At high intensity of RMF (B = 50 mT), the buoyancy convection is damped near the growth front, resulting in a more stable advancing interface. However, convection is strengthening in the upper part of the liquid zone, where the flow becomes unsteady. The multi-cellular unsteady flow generates temperature oscillations, having

  8. Salt effects on functional traits in model and in economically important Lotus species.

    PubMed

    Uchiya, P; Escaray, F J; Bilenca, D; Pieckenstain, F; Ruiz, O A; Menéndez, A B

    2016-07-01

    A common stress on plants is NaCl-derived soil salinity. Genus Lotus comprises model and economically important species, which have been studied regarding physiological responses to salinity. Leaf area ratio (LAR), root length ratio (RLR) and their components, specific leaf area (SLA) and leaf mass fraction (LMF) and specific root length (SRL) and root mass fraction (RMF) might be affected by high soil salinity. We characterised L. tenuis, L. corniculatus, L. filicaulis, L. creticus, L. burtii and L. japonicus grown under different salt concentrations (0, 50, 100 and 150 mm NaCl) on the basis of SLA, LMF, SRL and RMF using PCA. We also assessed effects of different salt concentrations on LAR and RLR in each species, and explored whether changes in these traits provide fitness benefit. Salinity (150 mm NaCl) increased LAR in L. burtii and L. corniculatus, but not in the remaining species. The highest salt concentration caused a decrease of RLR in L. japonicus Gifu, but not in the remaining species. Changes in LAR and RLR would not be adaptive, according to adaptiveness analysis, with the exception of SLA changes in L. corniculatus. PCA revealed that under favourable conditions plants optimise surfaces for light and nutrient acquisition (SLA and SRL), whereas at higher salt concentrations they favour carbon allocation to leaves and roots (LMF and RMF) in detriment to their surfaces. PCA also showed that L. creticus subjected to saline treatment was distinguished from the remaining Lotus species. We suggest that augmented carbon partitioning to leaves and roots could constitute a salt-alleviating mechanism through toxic ion dilution. PMID:27007305

  9. IBA investigations of loose garnets from Pietroasa, Apahida and Cluj-Someşeni treasures (5th century AD)

    NASA Astrophysics Data System (ADS)

    Bugoi, R.; Oanţă-Marghitu, R.; Calligaro, T.

    2016-03-01

    This paper reports the archaeometric investigations of 418 loose garnets from Pietroasa and Cluj-Someşeni treasures and Apahida II and III princely grave inventories (5th century AD). The chemical composition of the gems was determined by external beam micro-PIXE technique at the AGLAE accelerator of C2RMF, Paris, France. Complementary observations made by Optical Microscopy revealed details on the gemstones cutting and polishing and permitted to identify certain mineral inclusions. The compositional results evidenced several types of garnets from the pyralspite series, suggesting distinct provenances for these Early Medieval gems.

  10. A portable X-ray diffraction apparatus for in situ analyses of masters' paintings

    NASA Astrophysics Data System (ADS)

    Eveno, Myriam; Duran, Adrian; Castaing, Jacques

    2010-09-01

    It is rare that the analyses of materials in paintings can be carried out by taking micro-samples. Valuable works of art are best studied in situ by non-invasive techniques. For that purpose, a portable X-ray diffraction and fluorescence apparatus has been designed and constructed at the C2RMF. This apparatus has been used for paintings of Rembrandt, Leonardo da Vinci, Van Gogh, Mantegna, etc. Results are given to illustrate the performance of X-ray diffraction, especially when X-ray fluorescence does not bring sufficient information to conclude.

  11. Remote Field Eddy Current Probes for the Detection of Stress Corrosion in Transmission Pipelines

    SciTech Connect

    Plamen Alexandroz Ivanov

    2002-08-27

    Magnetic flux leakage (MFL) is a technique used widely in non-destructive testing (NDT) of natural gas and petroleum transmission pipelines. This inspection method relies on magnetizing the pipe-wall in axial direction. The MFL inspection tool is equipped with an array of Hall sensors located around the circumference of the pipe, which registers the flux leakage caused by any defects present in the pipe-wall. Currently, the tool magnetizes the pipewall in axial direction making it largely insensitive to axially oriented defects. One type of defect, which is of a growing concern in the gas and petroleum industry is the stress corrosion crack (SCC). The SCCs are a result of aging, corrosion, fatigue and thermal stresses. SCCs are predominantly axially oriented and are extremely tight, which makes them impossible to be detected using current inspection technology. A possible solution to this problem is to utilize the remote field eddy current (RFEC) effect to detect axially oriented defects. The RFEC method has been widely used in industry in the inspection of tubular products. The method uses a pair of excitation and pick-up coils. The pick-up coil located in the remote field region, usually two, three pipe-diameters away from the excitation coil. With RFEC the presence of defects is detected by the disturbance in the phase of the signal measured by the pick-up coil relative to that of the excitation coil. Unlike conventional eddy current testing the RFEC method is sensitive to defects on the exterior of the inspected product, which makes it a good candidate for the development of in-line inspection technology. This work focuses on the development of non-destructive testing technique, which uses remote field eddy currents induced by rotating magnetic field (RMF). A major advantage of the RMF is that it makes possible to not only detect a defect but also localize its position in circumferential direction. Also, it could potentially allow detection of defects

  12. Interaction radii of proton-rich radioactive nuclei at A=60-80

    SciTech Connect

    Lima, G. F.; Lepine-Szily, A.; Lichtenthaler, R.; Villari, A. C. C.; Mittig, W.; Casandjian, J. M.; Lewitowicz, M.; Chartier, M.; Hirata, D.; Angelique, J. C.; Orr, N. A.; Audi, G.; Cunsolo, A.; Foti, A.; Donzeaud, C.; MacCormick, M.; Stephan, C.; Suomijarvi, T.; Tassan-Got, L.; Gillibert, A.

    1998-12-21

    The interaction radii of proton-rich, radioactive {sub 31}Ga, {sub 32}Ge, {sub 33}As, {sub 34}Se, {sub 35}Br isotopes were measured using the direct method. The secondary beams were produced using a {sup 78}Kr primary beam of 73 MeV/nucleon in conjunction with SISSI and the SPEG spectrometers at GANIL. Most elements show reduced radii which vary with N, with a minimum around N=36-38. The experimental reduced radii are compared to theoretical values obtained from Glauber reaction cross-section calculations based on Relativistic Mean Field (RMF) nuclear densities.

  13. Transient Torque Technique for Viscosity and Electrical Conductivity Determination of Semiconducting Liquids

    NASA Technical Reports Server (NTRS)

    Li, C.; Scripa, R. N.; Ban, H.; Lin, B.; Su, C.-H.; Lehoczky, S. L.; Feth, S.; Zhu, S.; Curreri, Peter A. (Technical Monitor)

    2002-01-01

    A novel apparatus based on transient torque technique is constructed in MSFC/NASA. The apparatus uses a 125um diameter quartz fiber as torsion wire. A high sensitive angular detector is implemented to measure the deflection angle of the crucible containing the liquid. A rotating magnetic field (RMF) is used to induce a rotating flow of a conducting or semiconducting melts. By measuring the magnitude and transient behavior of the induced deflection angle, the electrical conductivity and viscosity of the melt can be measured simultaneously. High purity elements namely Hg, Ga, Zn and Te are tested at room temperature and high temperature up to 900 C.

  14. Thermal diffusivity of Zn1-xBexSe crystals and it's correlation with electrical conductivity and optical absorption spectra

    NASA Astrophysics Data System (ADS)

    Bodzenta, J.; Firszt, F.; Kaźmierczak-Bałata, A.; Pyka, M.; Szperlich, P.; Szydłowski, M.; Zakrzewski, J.

    2008-01-01

    This article presents results obtained for mixed crystal of Zn{1-x}Be{x}Se. Samples with different Be contents were examined to determine their thermal, optical and electrical properties. The influence of composition of investigated mixed crystals on the value of thermal diffusivity, electrical resistivity and energy gap was checked. An interesting problem is a correlation between thermal properties and other physical parameters. In this work possible correlations between the thermal diffusivity and either the optical band gap determined from photothermal spectra or electrical conductivity are studied. The current investigation is a part of research projects: BK-269/RMF-1/2006 and 1 P03B 092 27.

  15. Relativistic Mean Field description of exotic nuclei

    NASA Astrophysics Data System (ADS)

    Gambhir, Y. K.

    1994-03-01

    The Relativistic Mean Field (RMF) approach which essentially is an extension of the original σ — ω model of Walecka, has been applied to exotic nuclei as an illustration. We consider nuclei near Z = 34 in the very interesting 2p-1f region. The calculated binding energies, root mean square radii, deformations and other observables are very satisfactory and are in accordance with the experiment (where available) and also with the available empirical studies. Large deformations and shape co-existence are obtained for several cases.

  16. Exotic structures near the drip lines

    SciTech Connect

    Sharma, M. M.; Saldanha, A. A.; Sharma, J. K.

    2011-10-28

    In our recent study of the isotope shifts of Kr isotopes near rp-process path in the framework of the RMF theory, we have found that due to large shell gaps in the deformed space, several N = Z nuclei exhibit the double magicity of protons and neutrons. These nuclei are known to contribute to large abundances in the rp-process nucleosynthesis and have been shown to be the waiting-point nuclei. In another study of the shell effects at N = 126 near the neutron drip line, we have found that nuclei exhibit additional stability beyond the neutron drip line.

  17. The Effect of the Traveling Magnetic Field (TMF) on the Buoyancy-Induced Convection in the Vertical Bridgman growth of Germanium

    NASA Technical Reports Server (NTRS)

    Yesilyurt, S.; Motakef, S.; Grugel, R.; Mazuruk, K.

    2003-01-01

    A traveling magnetic field (TMF) is created by means of applying out-of-phase currents to a number of coils. When applied to a conducting melt inside a cylindrical container, the TMF induces a Lorentz force that acts in the meridional directions (radial and axial), unlike the application of a rotating magnetic field (RMF), which creates a force in the azimuthal direction. In this work, we present a computational study of the TMF and its application to the Bridgman growth of the Ge. To quantify the effect of the TMF on the solid-melt interface, we use the maximum (magnitude-wise) tangential shear at the interface.

  18. Solidification of II-VI Compounds in a Rotating Magnetic Field

    NASA Technical Reports Server (NTRS)

    Gillies, D. C.; Volz, M. P.; Mazuruk, K.; Motakef, S.; Dudley, M.; Matyi, R.

    1999-01-01

    This project is aimed at using a rotating magnetic field (RMF) to control fluid flow and transport during directional solidification of elemental and compound melts. Microgravity experiments have demonstrated that small amounts of residual acceleration of less than a micro-g can initiate and prolong fluid flow, particularly when there is a static component of the field perpendicular to the liquid solid interface. Thus a true diffusion boundary layer is not formed, and it becomes difficult to verify theories of solidification or to achieve diffusion controlled solidification. The RMF superimposes a stirring effect on an electrically conducting liquid, and with appropriate field strengths and frequencies, controlled transport of material through a liquid column can be obtained. As diffusion conditions are precluded and complete mixing conditions prevail, the technique is appropriate for traveling solvent zone or float zone growth methods in which the overall composition of the liquid can be maintained throughout the growth experiment. Crystals grown by RMF techniques in microgravity in previous, unrelated missions have shown exceptional properties. The objective of the project is two-fold, namely (1) using numerical modeling to simulate the behavior of a solvent zone with applied thermal boundary conditions and demonstrate the effects of decreasing gravity levels, or an increasing applied RMF, or both, and (2) to grow elements and II-VI compounds from traveling solvent zones both with and without applied RMFs, and to determine objectively how well the modeling predicts solidification parameters. Numerical modeling has demonstrated that, in the growth of CdTe from a tellurium solution, a rotating magnetic field can advantageously modify the shape of the liquid solid interface such that the interface is convex as seen from the liquid. Under such circumstances, the defect structure is reduced as any defects which are formed tend to grow out and not propagate. The flow

  19. Modes of decay in neutron-rich nuclei

    NASA Astrophysics Data System (ADS)

    Kumar, B.; Biswal, S. K.; Singh, S. K.; Lahiri, C.; Patra, S. K.

    2016-03-01

    We calculate the ground, first intrinsic excited states and density distribution for neutron-rich thorium and uranium isotopes, within the framework of relativistic mean field (RMF) approach using axially deformed basis. The total nucleon densities are calculated, from which the cluster-structures inside the parent nuclei are determined. The possible modes of decay, like α-decay and β-decay are analyzed. We find the neutron-rich isotopes are stable against α-decay, however they are very much unstable against β-decay. The life time of these nuclei predicted to be tens of second against β-decay.

  20. High-flying public information maneuvers or It's all up in the air

    SciTech Connect

    McKlveen, J.W.

    1989-01-01

    Two major public information programs have been developed by the Radiation Measurements Facility (RMF) at Arizona State University. One is associated with a nuclear power station and the other involves uranium mining in the Grand Canyon. Public information for both situations involved the usual speeches to schools and civic groups. However, a unique strategy was developed to accommodate the media. The laboratory has gained respect and a reputation for being caring, helpful, and honest-a place where one can go to get straight answers.

  1. One-pion exchange current effects on magnetic form factor in the relativistic formalism

    NASA Astrophysics Data System (ADS)

    Zhang, Cun; Liu, Jian; Ren, Zhongzhou

    2016-08-01

    One-pion exchange current effects on the magnetic form factors of some odd nuclei are studied in the relativistic formalism. The Dirac wave functions of nucleons are calculated from the relativistic mean-field theory. After fitting to experimental data by quenching factors, it is found that taking the one-pion exchange currents into account gives a better description of the magnetic form factor. The root-mean-square radii of the valance nucleon orbits are also calculated in RMF model, which coincide with experimental radii extracted with meson exchange current corrections.

  2. Turning research into results, final report

    SciTech Connect

    Not Available

    1993-05-01

    In September 1989, the ACEC Research and Management Foundation (ACEC/RMF) submitted a proposal to the US Department of Energy (DOE) in response to the Existing Buildings Efficiency Program`s Solicitation Number DE-PS01-89CE21034. On May 15, 1990, DOE informed ACEC/RMF that it had been selected for a grant award; the final agreement was signed on July 23, 1990. The purpose of the effort was to develop an information package showing engineering firms that energy services can be sold to owners and developers successfully and profitably, that not every design that goes beyond code results in a lawsuit, that owners can be shown the value of paying for the additional design analysis that energy efficiency design requires. The package was envisioned to include examples of buildings that succeed in terms of energy, cost, and design team benefits. It was further conceptualized as both a technical and marketing resource to provide helpful facts, references to relevant documents, graphic materials to be used during client presentations, and guidance on the latest in useful research results.

  3. Possible ambiguities in the equation of state for neutron stars

    SciTech Connect

    Cheoun, Myung-Ki; Miyatsu, Tsuyoshi; Ryu, C. Y.; Deliduman, Cemsinan; Güngör, Can; Keleş, Vildan; Kajino, Toshitaka; Mathews, Grant J.

    2014-05-02

    We addressed possible ambiguities on the properties of neutron stars (NSs) estimated in theoretical sides. First, roles of hyperons inside the NS are discussed through various relativistic mean field (RMF) theories. In particular, the extension of SU(6) spin-flavor symmetry to SU(3) flavor symmetry is shown to give rise to the increase of hyperon threshold density, similarly to the Fock term effects in RMF theories. As a result, about 2.0 solar mass is obtained with the hyperons. Second, the effect by the modified f(R) gravity, which leaves a room for the dark energy in the Einstein equation to be taken into account, is discussed for the NS in a strong magnetic field (MF). Our results show that the modified gravity with the Kaluza-Klein electro-magnetism theory expanded in terms of a length scale parameter may reasonably describe the NS in strong MF, so called magnetar. Even the super-soft equation of state is shown to be revived by the modified f(R) gravity.

  4. Influence of glutathione on the bioactivity of subcutaneously or orally administered insulin to rats.

    PubMed

    Al-Kurdi, Zakieh I; Chowdhry, Babur Z; Leharne, Stephen A; Qinna, Nidal A; Al-Omari, Mahmoud M H; Badwan, Adnan A

    2015-01-01

    The effect of reduced (GSH) and oxidized (GSSG) glutathione on the bioactivity of insulin was studied. A polyelectrolyte complex (PEC) of insulin with low molecular weight chitosan (13 kDa) was prepared and characterized. The PEC was then solubilized, in the presence and absence of GSH and GSSG, in a reverse micelle consisting of oleic acid and two surfactants (PEG-8 caprylic/capric glycerides and polyglycerol-6-dioleate). The in vitro and in vivo performances of the reverse micelle formulations (RMFs) were evaluated in rats. At pH 6.5 the association efficiency of the PEC was 76.2%. In vitro insulin release from the RMs was negligible at pH 1.2 and was markedly increased at pH 6.8. The hypoglycemic activity of insulin in the PEC was reduced when administered via the subcutaneous route, regardless of the GSH content. On the other hand, the presence of GSSG significantly enhanced hypoglycemia. When the RMF was administered via the oral route, the presence of GSH had no effect on the hypoglycemic activity of insulin compared with the GSH free system. However, the presence of GSSG in the oral preparation increased the hypoglycemic activity of insulin; probably by inhibiting insulin degradation, thereby prolonging its effect. Thus, incorporation of GSSG in the RMF reduces blood glucose levels in rats and protects insulin from degradation. PMID:25896162

  5. Methods of Viscosity Measurements in Sealed Ampoules

    NASA Technical Reports Server (NTRS)

    Mazuruk, Konstantin

    1999-01-01

    Viscosity of semiconductor and metallic melts is usually measured by oscillating cup method. This method utilizes the melts contained in vacuum sealed silica ampoules, thus the problems related to volatility, contamination, and high temperature and pressure can be alleviated. In a typical design, the time required for a single measurement is of the order of one hour. In order to reduce this time to a minute range, a high resolution (0.05 arc.sec) angular detection system is implemented in our design of the viscometer. Furthermore, an electromagnet generating a rotational magnetic field (RMF) is incorporated into the apparatus. This magnetic field can be used to remotely and non intrusively measure the electrical conductivity of the melt. It can also be used to induce a well controlled rotational flow in the system. The transient behavior of this flow can potentially yield the viscosity of the fluid. Based on RMF implementation, two novel viscometry methods are proposed in this work: a) the transient torque method, b) the resonance method. A unified theoretical approach to the three methods (oscillating cup, transient torque, and resonance) is presented along with the initial test results of the constructed apparatus. Advantages of each of the method are discussed.

  6. Superfluidity of {Lambda} hyperons in neutron stars

    SciTech Connect

    Wang, Y. N.; Shen, H.

    2010-02-15

    We study the {sup 1}S{sub 0} superfluidity of {Lambda} hyperons in neutron star matter and neutron stars. We use the relativistic mean field (RMF) theory to calculate the properties of neutron star matter. In the RMF approach, the meson-hyperon couplings are constrained by reasonable hyperon potentials that include the updated information from recent developments in hypernuclear physics. To examine the {sup 1}S{sub 0} pairing gap of {Lambda} hyperons, we employ several {Lambda}{Lambda} interactions based on the Nijmegen models and used in double-{Lambda} hypernuclei studies. It is found that the maximal pairing gap obtained is a few tenths of a MeV. The magnitude and the density region of the pairing gap are dependent on the {Lambda}{Lambda} interaction and the treatment of neutron star matter. We calculate neutron star properties and find that whether the {sup 1}S{sub 0} superfluidity of {Lambda} hyperons exists in the core of neutron stars mainly depends on the {Lambda}{Lambda} interaction used.

  7. Mycoplasma hyopneumoniae and Mycoplasma flocculare differential domains from orthologous surface proteins induce distinct cellular immune responses in mice.

    PubMed

    Leal, Fernanda Munhoz Dos Anjos; Virginio, Veridiana Gomes; Martello, Carolina Lumertz; Paes, Jéssica Andrade; Borges, Thiago J; Jaeger, Natália; Bonorino, Cristina; Ferreira, Henrique Bunselmeyer

    2016-07-15

    Mycoplasma hyopneumoniae and Mycoplasma flocculare are two genetically close species found in the swine respiratory tract. Despite their similarities, while M. hyopneumoniae is the causative agent of porcine enzootic pneumonia, M. flocculare is a commensal bacterium. Genomic and transcriptional comparative analyses so far failed to explain the difference in pathogenicity between these two species. We then hypothesized that such difference might be, at least in part, explained by amino acid sequence and immunological or functional differences between ortholog surface proteins. In line with that, it was verified that approximately 85% of the ortholog surface proteins from M. hyopneumoniae 7448 and M. flocculare present one or more differential domains. To experimentally assess possible immunological implications of this kind of difference, the extracellular differential domains from one pair of orthologous surface proteins (MHP7448_0612, from M. hyopneumoniae, and MF_00357, from M. flocculare) were expressed in E. coli and used to immunize mice. The recombinant polypeptides (rMHP61267-169 and rMF35767-196, respectively) induced distinct cellular immune responses. While, rMHP61267-169 induced both Th1 and Th2 responses, rMF35767-196 induced just an early pro-inflammatory response. These results indicate that immunological properties determined by differential domains in orthologous surface protein might play a role in pathogenicity, contributing to elicit specific and differential immune responses against each species. PMID:27283856

  8. Superdeformed states in hypernuclei with antisymmetrized molecular dynamics

    NASA Astrophysics Data System (ADS)

    Isaka, Masahiro; Kimura, Masaaki; Hiyama, Emiko; Sagawa, Hiroyuki

    2014-09-01

    One of the main purposes of hypernuclear physics is to reveal the responses to the addition of a Λ particle in (hyper)nuclei. Recently, as an example of such responses, several authors investigated the difference of BΛ between the spherical (ground) and largely deformed (superdeformed) states. For example, the relativistic mean-field (RMF) calculations predicted the large BΛ in the superdeformed states in several Λ hypernuclei such as Λ37Ar and Λ39Ar. On the other hand, in Λ41Ca and Λ46Sc, it was discussed that BΛ in the spherical states is larger than that in the superdeformed states based on the antisymmetrized molecular dynamics (AMD). In the present study, we have applied the AMD to Ar Λ hypernuclei to reveal the difference of BΛ between the spherical and superdeformed states. Especially, we will focus on Λ39Ar as well as Λ37Ar, because it would be possible to produce Λ39Ar by the JLab experiments. In this talk, we will show the difference of BΛ in Ar hypernuclei and compare it with the previous AMD results and RMF predictions. Furthermore, we will predict the changes of the excitation spectra in Λ39Ar due to the difference of BΛ.

  9. Neutron density distribution and the halo structure of {sup 22}C

    SciTech Connect

    Sharma, Manjari; Khan, Z. A.; Haider, W.; Bhagwat, A.; Gambhir, Y. K.

    2011-03-15

    The recently measured reaction cross sections for the neutron-rich carbon isotopes ({sup 19}C, {sup 20}C, and {sup 22}C) on a proton target at 40 A MeV are analyzed using the finite range Glauber model (FRGM) and the microscopic optical potential calculated within the Brueckner-Hartree-Fock formalism (BHF). In FRGM nucleon-nucleon cross sections are used, while in the latter (BHF), Hamada-Johnston, Urbana v-14, and the Argonne v-18 internucleon potentials are employed to calculate the microscopic optical potential. The required nucleon density distributions are calculated within the relativistic mean-field (RMF) framework. To test the halo structure, the extended neutron density distribution for {sup 22}C is also used. The analysis reveals that the BHF results of all three internucleon potentials are very close to each other, and also agree with the corresponding results of the FRGM. Our results, using RMF densities, are in agreement with the experimental data for all isotopes of carbon except {sup 22}C, for which we require extended neutron density distribution, indicating a halo structure.

  10. Tornado-like flows driven by magnetic body forces

    NASA Astrophysics Data System (ADS)

    Gerbeth, Gunter; Grants, Ilmars; Vogt, Tobias; Eckert, Sven

    2014-11-01

    Alternating magnetic fields produce well-defined flow-independent body forces in electrically conducting media. This property is used to construct a laboratory analogue of the Fiedler chamber with a room-temperature liquid metal as working fluid. A continuously applied rotating magnetic field (RMF) provides the source of the angular momentum. A pulse of a much stronger travelling magnetic field drives a converging flow at the metal surface, which focuses this angular momentum towards the axis of the container. The resulting vortex is studied experimentally and numerically. In a certain range of the ratio of both driving actions the axial velocity changes its direction in the vortex core, resembling the subsidence in an eye of a tropical cyclone or a large tornado. During the initial deterministic spin-up stage the vortex is well described by axisymmetric direct numerical simulation. Being strong enough the flow develops a funnel-shaped surface depression that enables visual observation of the vortex structure. As the RMF strength is increased the eyewall diameter grows until it breaks down to multiple vortices. A number of further observed similarities to tornado-like vortices will be discussed. The work is supported by the German Helmholtz Association in frame of the LIMTECH alliance.

  11. Release measurements for materials out of controlled areas

    PubMed

    Auler; Neukater; Franz; Krebs

    2000-07-01

    Large amounts of dismantled materials from nuclear power plants show such a weak level of radioactivity that they could be released after decision measurements. Till some years ago, the decision measurements taken for the release were based only on determining the mass-specific activity of samples by means of gamma spectrometry and/or manual sequential measurements of the surface activity with large area gas flow counters. The choice of an appropriate measuring method, the layout of the release measurement facility (RMF), the way of preparing the material and the development of smart release procedures are very important for a large throughput and an economic performance of the release process. NIS and RADOS have developed RMF based on gross gamma activity. The NIS-RMFs have been applied for the last 10 years for decision measurements in different operated but also in dismantled nuclear power plants. Together with RMFs from RADOS, more than 12,000 Mg of various types of materials have been measured up to now with this method in Germany. PMID:10879881

  12. Relativistic mean-field models and nuclear matter constraints

    SciTech Connect

    Dutra, M.; Lourenco, O.; Carlson, B. V.; Delfino, A.; Menezes, D. P.; Avancini, S. S.; Stone, J. R.; Providencia, C.; Typel, S.

    2013-05-06

    This work presents a preliminary study of 147 relativistic mean-field (RMF) hadronic models used in the literature, regarding their behavior in the nuclear matter regime. We analyze here different kinds of such models, namely: (i) linear models, (ii) nonlinear {sigma}{sup 3}+{sigma}{sup 4} models, (iii) {sigma}{sup 3}+{sigma}{sup 4}+{omega}{sup 4} models, (iv) models containing mixing terms in the fields {sigma} and {omega}, (v) density dependent models, and (vi) point-coupling ones. In the finite range models, the attractive (repulsive) interaction is described in the Lagrangian density by the {sigma} ({omega}) field. The isospin dependence of the interaction is modeled by the {rho} meson field. We submit these sets of RMF models to eleven macroscopic (experimental and empirical) constraints, used in a recent study in which 240 Skyrme parametrizations were analyzed. Such constraints cover a wide range of properties related to symmetric nuclear matter (SNM), pure neutron matter (PNM), and both SNM and PNM.

  13. EVALUATION OF ALTERNATIVE FILTER MEDIA FOR THE ROTARY MICROFILTER, PHASE 2

    SciTech Connect

    Fowley, M.

    2012-07-31

    Testing was conducted at the Savannah River National Laboratory (SRNL) to investigate filter membrane performance in an effort to increase rotary microfilter (RMF) throughput. Membranes were tested in the SpinTek Filtration, Inc. Static Test Cell (STC), which permitted quick and easy testing of several different membranes. Testing consisted of 100 hours tests with two different slurry feeds, based on recommendations from the phase 1 testing. One feed contained Monosodium Titanate (MST) solids in a simulated salt solution. The other feed contained simulated sludge batch 6 (SB6) solids in a simulated salt solution. Five membranes were tested, one each from filter manufactures Pall and Porvair and three from the Oak Ridge National Laboratory (ORNL). The membrane from Pall is the current membrane used on the latest generation RMF. The Porvair membrane performed well in previous STC tests as well as one of the ORNL membranes. The other two membranes from ORNL were recently developed and not available for the previous STC test. The results indicate that the Porvair filter performed best with the MST slurry and the ORNL SVB6-1B filter performed best with the SB6 slurry. Difficulty was encountered with the ORNL filters due to their dimensional thickness, which was greater than the recommended filter thickness for the STC. The STC equipment was modified to complete the testing of the ORNL filters.

  14. Multi-K nuclei and kaon condensation

    SciTech Connect

    Gazda, D.; Mares, J.; Friedman, E.; Gal, A.

    2008-04-15

    We extend previous relativistic mean-field (RMF) calculations of multi-K nuclei, using vector boson fields with SU(3) PPV coupling constants and scalar boson fields constrained phenomenologically. For a given core nucleus, the resulting K separation energy B{sub K}, as well as the associated nuclear and K-meson densities, saturate with the number {kappa} of K mesons for {kappa}>{kappa}{sub sat}{approx}10. Saturation appears robust against a wide range of variations, including the RMF nuclear model used and the type of boson fields mediating the strong interactions. Because B{sub K} generally does not exceed 200 MeV, it is argued that multi-K nuclei do not compete with multihyperonic nuclei in providing the ground state of strange hadronic configurations and that kaon condensation is unlikely to occur in strong-interaction self-bound strange hadronic matter. Last, we explore possibly self-bound strange systems made of neutrons and K{sup 0} mesons, or protons and K{sup -} mesons, and study their properties.

  15. Antidiarrhoeal activity of the methanol extract of the barks of Xylocarpus moluccensis in castor oil- and magnesium sulphate-induced diarrhoea models in mice.

    PubMed

    Uddin, S J; Shilpi, J A; Alam, S M S; Alamgir, M; Rahman, M T; Sarker, S D

    2005-10-01

    The methanol (MeOH) extract of the barks of Xylocarpus moluccensis, and different fractions of this extract were studied for antidiarrhoeal activity using castor oil- and magnesium sulphate-induced diarrhoea models in mice. At the doses of 250 and 500 mg/kg, the MeOH extract showed significant antidiarrhoeal activity in both models. The EtOAc fraction (EAF) and the residual MeOH fraction (RMF) exhibited similar activity using a dose of 250 mg/kg in both models. No antidiarrhoeal activity was observed with the chloroform fraction (CHF) at the test doses. When tested for antibacterial effect, the MeOH extract displayed moderate inhibitory activity against Escherichia coli, Vibrio cholera, Staphylococcus aureus, Staphylococcus epidermis, Shigella dysentery, Staphylococcus pyogenes, Salmonella typhi, Pseudomonas aeruginosa and Enterobacter aerogenes. While the CHF inhibited the growth of Escherichia coli, Vibrio cholerae, Shigella dysenteriae, Shigella sonnei, Staphylococcus epidermis, Staphylococcus pyogenes and Pseudomonas aeruginosa, the EAF was active against all test organisms except Vibrio cholera and Staphylococcus epidermis. The RMF inhibited the growth of all the test organisms with moderate zone of inhibition. On the basis of these findings, it can be assumed that Xylocarpus moluccensis could be a potential source for novel 'lead' discovery for antidiarrhoeal drug development. PMID:15905054

  16. Lifetime measurements in 166Re: Collective versus magnetic rotation

    NASA Astrophysics Data System (ADS)

    Li, H. J.; Cederwall, B.; Doncel, M.; Peng, J.; Chen, Q. B.; Zhang, S. Q.; Zhao, P. W.; Meng, J.; Bäck, T.; Jakobsson, U.; Auranen, K.; Bönig, S.; Drummond, M.; Grahn, T.; Greenlees, P.; HerzáÅ, A.; Joss, D. T.; Julin, R.; Juutinen, S.; Konki, J.; Kröll, T.; Leino, M.; McPeake, C.; O'Donnell, D.; Page, R. D.; Pakarinen, J.; Partanen, J.; Peura, P.; Rahkila, P.; Ruotsalainen, P.; Sandzelius, M.; Sarén, J.; Sayǧı, B.; Scholey, C.; Sorri, J.; Stolze, S.; Taylor, M. J.; Thornthwaite, A.; Uusitalo, J.; Xiao, Z. G.

    2016-03-01

    Lifetimes of excited states in the neutron-deficient odd-odd nucleus 166Re have been measured for the first time using the recoil distance Doppler-shift method. The measured lifetime for the (8-) state; τ =480 (80) ps, enabled an assessment of the multipolarities of the γ rays depopulating this state. Information on electromagnetic transition strengths were deduced for the γ -ray transitions from the (9-),(10-), and (11-) states, and in the case of the (10-) and (11-) states limits on the B (M 1 ) and B (E 2 ) strengths were estimated. The results are compared with total Routhian surface predictions and semiclassical calculations. Tilted-axis cranking calculations based on a relativistic mean-field approach (TAC-RMF) have also been performed in order to test the possibility of magnetic rotation in the 166Re nucleus. While the TAC-RMF calculations predict a quadrupole-deformed nuclear shape with similar β2 deformation as obtained by using the TRS model, it was found that the experimental electromagnetic transition rates are in better agreement with a collective-rotational description.

  17. Determination of hadron-quark phase transition line from lattice QCD and two-solar-mass neutron star observations

    NASA Astrophysics Data System (ADS)

    Sugano, Junpei; Kouno, Hiroaki; Yahiro, Masanobu

    2016-07-01

    We aim at drawing the hadron-quark phase transition line in the QCD phase diagram by using the two-phase model (TPM) in which the entanglement Polyakov-loop extended Nambu-Jona-Lasinio (EPNJL) model with the vector-type four-quark interaction is used for the quark phase and the relativistic mean field (RMF) model is used for the hadron phase. A reasonable TPM is constructed by using lattice QCD data and neutron star observations as reliable constraints. For the EPNJL model, we determine the strength of vector-type four-quark interaction at zero quark chemical potential from lattice QCD data on quark number density normalized by its Stefan-Boltzmann limit. For the hadron phase, we consider three RMF models: NL3; TM1; and the model proposed by Maruyama, Tatsumi, Endo, and Chiba (MTEC). We find that MTEC is most consistent with the neutron star observations and TM1 is the second best. Assuming that the hadron-quark phase transition occurs in the core of a neutron star, we explore the density dependence of vector-type four-quark interaction. Particularly for the critical baryon chemical potential μBc at zero temperature, we determine a range of μBc for the quark phase to occur in the core of a neutron star. The values of μBc lie in the range 1560 MeV ≤μBc≤1910 MeV .

  18. Twenty-channel bolometer array for studying impurity radiation and transport in the TCS field-reversed configuration

    NASA Astrophysics Data System (ADS)

    Kostora, M. R.; Hsu, S. C.; Wurden, G. A.

    2006-10-01

    A bolometer array diagnostic has been developed for the University of Washington Translation, Confinement, and Sustainment (TCS) field-reversed configuration (FRC) experiment in order to measure radially resolved total radiated power per unit length of the FRC. This will provide radiation energy loss information, useful in power balance and impurity studies. The 20-element photodiode bolometer will be mounted at the midplane of the TCS cylindrical vacuum chamber to view the rotating magnetic field (RMF) generated FRC plasma. Key features of this new bolometer array are (1) extensive electrical shielding against the RMF, (2) robust electrical isolation, (3) trans-impedance amplifiers using a microcoax interface at the array and a fiber optic interface to the screen room, and (4) a custom glass-on-metal socket for the 20-element photodiode chip to ensure high vacuum compatibility. The bolometer array can be retracted behind a gate valve using a stepper motor to protect it during vacuum chamber bakeout. The slit assembly housing is interchangeable to provide flexibility for the viewing sightlines.

  19. Comparative study of nuclear masses in the relativistic mean-field model

    NASA Astrophysics Data System (ADS)

    Hua, XueMin; Heng, TaiHua; Niu, ZhongMing; Sun, BaoHua; Guo, JianYou

    2012-12-01

    With experimental masses updated from AME11, the predictive power of relativistic mean-field (RMF) mass model is carefully examined and compared with HFB-17, FRDM, WS*, and DZ28 mass models. In the relativistic mean-field model, the calculation with the PC-PK1 has improved significantly in describing masses compared to the TMA, especially for the neutron-deficient nuclei. The corresponding rms deviation with respect to the known masses falls to 1.4 MeV. Furthermore, it is found that the RMF mass model better describes the nuclei with large deformations. The rms deviation for nuclei with the absolute value of quadrupole deformation parameter greater than 0.25 falls to 0.93, crossing the 1 MeV accuracy threshold for the PC-PK1, which may indicate the new model is more suitable for those largely-deformed nuclei. In addition, the necessity of new high-precision experimental data to evaluate and develop the nuclear mass models is emphasized as well.

  20. Adaptive Control of Non-Minimum Phase Modal Systems Using Residual Mode Filters2. Parts 1 and 2

    NASA Technical Reports Server (NTRS)

    Balas, Mark J.; Frost, Susan

    2011-01-01

    Many dynamic systems containing a large number of modes can benefit from adaptive control techniques, which are well suited to applications that have unknown parameters and poorly known operating conditions. In this paper, we focus on a direct adaptive control approach that has been extended to handle adaptive rejection of persistent disturbances. We extend this adaptive control theory to accommodate problematic modal subsystems of a plant that inhibit the adaptive controller by causing the open-loop plant to be non-minimum phase. We will modify the adaptive controller with a Residual Mode Filter (RMF) to compensate for problematic modal subsystems, thereby allowing the system to satisfy the requirements for the adaptive controller to have guaranteed convergence and bounded gains. This paper will be divided into two parts. Here in Part I we will review the basic adaptive control approach and introduce the primary ideas. In Part II, we will present the RMF methodology and complete the proofs of all our results. Also, we will apply the above theoretical results to a simple flexible structure example to illustrate the behavior with and without the residual mode filter.

  1. Relativistic mean-field hadronic models under nuclear matter constraints

    NASA Astrophysics Data System (ADS)

    Dutra, M.; Lourenço, O.; Avancini, S. S.; Carlson, B. V.; Delfino, A.; Menezes, D. P.; Providência, C.; Typel, S.; Stone, J. R.

    2014-11-01

    Background: The microscopic composition and properties of infinite hadronic matter at a wide range of densities and temperatures have been subjects of intense investigation for decades. The equation of state (EoS) relating pressure, energy density, and temperature at a given particle number density is essential for modeling compact astrophysical objects such as neutron stars, core-collapse supernovae, and related phenomena, including the creation of chemical elements in the universe. The EoS depends not only on the particles present in the matter, but, more importantly, also on the forces acting among them. Because a realistic and quantitative description of infinite hadronic matter and nuclei from first principles in not available at present, a large variety of phenomenological models has been developed in the past several decades, but the scarcity of experimental and observational data does not allow a unique determination of the adjustable parameters. Purpose: It is essential for further development of the field to determine the most realistic parameter sets and to use them consistently. Recently, a set of constraints on properties of nuclear matter was formed and the performance of 240 nonrelativistic Skyrme parametrizations was assessed [M. Dutra et al., Phys. Rev. C 85, 035201 (2012), 10.1103/PhysRevC.85.035201] in describing nuclear matter up to about three times nuclear saturation density. In the present work we examine 263 relativistic-mean-field (RMF) models in a comparable approach. These models have been widely used because of several important aspects not always present in nonrelativistic models, such as intrinsic Lorentz covariance, automatic inclusion of spin, appropriate saturation mechanism for nuclear matter, causality, and, therefore, no problems related to superluminal speed of sound in medium. Method: Three different sets of constraints related to symmetric nuclear matter, pure neutron matter, symmetry energy, and its derivatives were used. The

  2. Strength of nuclear shell effects at N=126 in the r-process region

    SciTech Connect

    Farhan, A.R.; Sharma, M.M.

    2006-04-15

    We have investigated nuclear-shell effects across the magic number N=126 in the region of the r-process path. Microscopic calculations have been performed using the relativistic Hartree-Bogoliubov approach within the framework of the relativistic mean-field (RMF) theory for isotopic chains of rare-earth nuclei in the r-process region. The Lagrangian model NL-SV1 with the inclusion of the vector self-coupling of {omega} meson has been employed. The RMF results show that the shell effects at N=126 remain strong and exhibit only a slight reduction in the strength in going from the r-process path to the neutron drip line. This is in striking contrast to a systematic weakening of the shell effects at N=82 in the r-process region predicted earlier in the similar approach. In comparison the shell effects with microscopic-macroscopic mass formulas show a near constancy of shell gaps leading to strong shell effects in the region of r-process path to the drip line. A recent analysis of solar-system r-process abundances in a prompt supernova explosion model using various mass formulas, including the recently introduced mass tables based on Hartree-Fock-Bogoliubov method shows that although mass formulas with weak shell effects at N=126 give rise to a spread and an overproduction of nuclides near the third abundance peak at A{approx}190, mass tables with droplet models showing stronger shell effects are able to reproduce the abundance features near the third peak appropriately. In comparison, several analyses of the second r-process peak at A{approx}130 have required weakened (quenched) shell effects at N=82. Our predictions in the RMF theory with NL-SV1, which exhibit weaker shell effects at N=82 and correspondingly stronger shell effects at N=126 in the r-process region, support the conjecture that a different nature of the shell effects at the magic numbers may be at play in r-process nucleosynthesis of heavy nuclei.

  3. Land-Cover Change Within the Peatlands Along the Rocky Mountain Front, Montana: 1937-2009

    NASA Astrophysics Data System (ADS)

    Klene, A. E.; Milbrath, J. T.; Shelly, J. S.

    2013-12-01

    While peatlands are globally abundant, the fens of the Rocky Mountain Front (RMF), are the eastern-most, rich, peatlands in Montana, and are unique wetland habitats in this region of semi-arid continental climate. The peatlands provide critical riparian connectivity between the mountains and the plains and are habitat for grizzly bears, wolves, and within just the 450 ha Pine Butte Fen at least 93 species of vascular plants, including seven of Montana's Plant Species of Concern. Aerial photographs of the nine peatlands along the RMF in Montana were analyzed in a GIS. The boundary of each wetland was hand-digitized and the area within was classified into land-cover types: total area, open fen, open water, woody vegetation, and non-wetland/agriculture. Changes in wetland extent and land-cover categories were evaluated from the earliest available imagery in 1937 to the last available imagery in 2009. Images prior to 1995 were orthorectified, and all georectified. Climate change, wildlife, and agriculture were examined as potential drivers of land-cover change at these sites. Results indicate little change in overall peatland area between 1937 and 2009 despite increasing air temperatures in the region. Approximately 16% of these peatlands is 'open fen' and that proportion remained stable over the last seventy years. Area of open water quadrupled and the number of ponds which could be delineated tripled over the study period, reflecting a recovering beaver population. The non-wetland/agricultural area halved over the course of the study, primarily due to declines in agriculture within the three largest remaining peatlands: Pine Butte Fen, McDonald Swamp, and the Blackleaf Creek wetland complex. Most of the first two fens were purchased outright by the Nature Conservancy (TNC) and they hold a conservation easement on the third (as well as two other fens), all of which have been been put in place since the late 1970s. One fen is owned by the State of Montana and another

  4. Semiconductor Crystal Growth in Static and Rotating Magnetic fields

    NASA Technical Reports Server (NTRS)

    Volz, Martin

    2004-01-01

    Magnetic fields have been applied during the growth of bulk semiconductor crystals to control the convective flow behavior of the melt. A static magnetic field established Lorentz forces which tend to reduce the convective intensity in the melt. At sufficiently high magnetic field strengths, a boundary layer is established ahead of the solid-liquid interface where mass transport is dominated by diffusion. This can have a significant effect on segregation behavior and can eliminate striations in grown crystals resulting from convective instabilities. Experiments on dilute (Ge:Ga) and solid solution (Ge-Si) semiconductor systems show a transition from a completely mixed convective state to a diffusion-controlled state between 0 and 5 Tesla. In HgCdTe, radial segregation approached the diffusion limited regime and the curvature of the solid-liquid interface was reduced by a factor of 3 during growth in magnetic fields in excess of 0.5 Tesla. Convection can also be controlled during growth at reduced gravitational levels. However, the direction of the residual steady-state acceleration vector can compromise this effect if it cannot be controlled. A magnetic field in reduced gravity can suppress disturbances caused by residual transverse accelerations and by random non-steady accelerations. Indeed, a joint program between NASA and the NHMFL resulted in the construction of a prototype spaceflight magnet for crystal growth applications. An alternative to the suppression of convection by static magnetic fields and reduced gravity is the imposition of controlled steady flow generated by rotating magnetic fields (RMF)'s. The potential benefits of an RMF include homogenization of the melt temperature and concentration distribution, and control of the solid-liquid interface shape. Adjusting the strength and frequency of the applied magnetic field allows tailoring of the resultant flow field. A limitation of RMF's is that they introduce deleterious instabilities above a

  5. Interaction radii of proton-rich radioactive nuclei at A=60{endash}80

    SciTech Connect

    Lima, G.F.; Lepine-Szily, A.; Villari, A.C.; Lichtenthaler, R.; Villari, A.C.; Mittig, W.; Chartier, M.; Casandjian, J.M.; Lewitowicz, M.; Ostrowski, A.N.; Hirata, D.; Angelique, J.C.; Orr, N.A.; Audi, G.; Cunsolo, A.; Foti, A.; Donzeaud, C.; MacCormick, M.; Stephan, C.; Suomijarvi, T.; Tassan-Got, L.; Gillibert, A.; Chartier, M.; Morrissey, D.J.; Sherrill, B.M.; Ostrowski, A.N.; Vieira, D.J.; Wouters, J.M.

    1998-12-01

    The interaction radii of proton-rich, radioactive {sub 31}Ga,thinsp{sub 32}Ge,thinsp{sub 33}As,thinsp{sub 34}Se,thinsp{sub 35}Br isotopes were measured using the direct method. The secondary beams were produced using a {sup 78}Kr primary beam of 73 MeV/nucleon in conjunction with SISSI and the SPEG spectrometers at GANIL. Most elements show reduced radii which vary with N, with a minimum around N=36{endash}38. The experimental reduced radii are compared to theoretical values obtained from Glauber reaction cross-section calculations based on Relativistic Mean Field (RMF) nuclear densities. {copyright} {ital 1998 American Institute of Physics.}

  6. Superdeformed and hyperdeformed states in Z=122 isotopes

    SciTech Connect

    Patra, S. K.; Bhuyan, M.; Mehta, M. S.; Gupta, Raj K.

    2009-09-15

    We calculate the binding energy, root-mean-square radius, and quadrupole deformation parameter for the recent, possibly discovered superheavy element Z=122, using the axially deformed relativistic mean-field (RMF) and nonrelativistic Skyrme Hartree-Fock (SHF) formalisms. The calculation is extended to include various isotopes of Z=122 element, starting from A=282 to A=320. We predict highly deformed structures in the ground state for all the isotopes. A shape transition appears at about A=290 from a highly oblate to a large prolate shape, which may be considered as the superdeformed and hyperdeformed structures of the Z=122 nucleus in the mean-field approaches. The most stable isotope (largest binding energy per nucleon) is found to be {sup 302}122, instead of the experimentally observed {sup 292}122.

  7. Application of relativistic mean field and effective field theory densities to scattering observables for Ca isotopes

    NASA Astrophysics Data System (ADS)

    Bhuyan, M.; Panda, R. N.; Routray, T. R.; Patra, S. K.

    2010-12-01

    In the framework of relativistic mean field (RMF) theory, we have calculated the density distribution of protons and neutrons for Ca40,42,44,48 with NL3 and G2 parameter sets. The microscopic proton-nucleus optical potentials for p+Ca40,42,44,48 systems are evaluated from the Dirac nucleon-nucleon scattering amplitude and the density of the target nucleus using relativistic-Love-Franey and McNeil-Ray-Wallace parametrizations. We have estimated the scattering observables, such as the elastic differential scattering cross section, analyzing power and the spin observables with the relativistic impulse approximation (RIA). The results have been compared with the experimental data for a few selective cases and we find that the use of density as well as the scattering matrix parametrizations are crucial for the theoretical prediction.

  8. Application of relativistic mean field and effective field theory densities to scattering observables for Ca isotopes

    SciTech Connect

    Bhuyan, M.; Panda, R. N.; Routray, T. R.; Patra, S. K.

    2010-12-15

    In the framework of relativistic mean field (RMF) theory, we have calculated the density distribution of protons and neutrons for {sup 40,42,44,48}Ca with NL3 and G2 parameter sets. The microscopic proton-nucleus optical potentials for p+{sup 40,42,44,48}Ca systems are evaluated from the Dirac nucleon-nucleon scattering amplitude and the density of the target nucleus using relativistic-Love-Franey and McNeil-Ray-Wallace parametrizations. We have estimated the scattering observables, such as the elastic differential scattering cross section, analyzing power and the spin observables with the relativistic impulse approximation (RIA). The results have been compared with the experimental data for a few selective cases and we find that the use of density as well as the scattering matrix parametrizations are crucial for the theoretical prediction.

  9. Adaptation of the projection-slice theorem for stock valuation estimation using random Markov fields

    NASA Astrophysics Data System (ADS)

    Riasati, Vahid R.

    2009-04-01

    The Projection-Slice Synthetic Discriminant function filter is utilized with Random Markov Fields, RMF to estimate trends that may be used as prediction for stock valuation through the representation of the market behavior as a hidden Markov Model, HMM. In this work, we utilize a set of progressive and contiguous time segments of a given stock, and treat the set as a two dimensional object that has been represented by its one-d projections. The abstract two-D object is thus an incarnation of N-temporal projections. The HMM is then utilized to generate N+1 projections that maximizes the two-dimensional correlation peak between the data and the HMM-generated stochastic processes. This application of the PSDF provides a method of stock valuation prediction via the market stochastic behavior utilized in the filter.

  10. Search for multiple chiral doublets in rhodium isotopes

    SciTech Connect

    Peng, J.; Sagawa, H.; Zhang, S. Q.; Yao, J. M.; Zhang, Y.; Meng, J.

    2008-02-15

    The deformation in rhodium isotopes is investigated using adiabatic and configuration-fixed constrained triaxial relativistic mean field (RMF) approaches. The triaxial deformations are found in the ground states of {sup 102,104,106,108,110}Rh, which is consistent with triaxial Skyrme Hartree-Fock calculations. Several minima with triaxial deformation in {sup 104,106,108,110}Rh are obtained by the configuration-fixed constrained calculations. The corresponding configurations are characterized by the quantum numbers |nljm> obtained by transforming wave functions from a Cartesian basis to a spherical basis. The possible existence of multiple chiral doublets (M{chi}D) is demonstrated in {sup 104,106,108,110}Rh isotopes, based on different particle-hole configurations and triaxial deformations.

  11. Computer program for the relativistic mean field description of the ground state properties of even-even axially deformed nuclei

    NASA Astrophysics Data System (ADS)

    Ring, P.; Gambhir, Y. K.; Lalazissis, G. A.

    1997-09-01

    We present a Fortran program for the calculation of the ground state properties of axially deformed even-even nuclei in the framework of Relativistic Mean Field Theory (RMF). In this approach a set of coupled partial differentials has to be solved self-consistently: the Dirac equation for the nucleons moving in self-consistent fields and the Klein-Gordon equations for the meson fields and the electromagnetic field, whose sources are scalar and vector densities determined of the nucleons. For this purpose the Dirac spinors as well as the meson fields are expanded in terms of anisotropic oscillator wave functions in cylindrical coordinates. This requires a matrix diagonalization for the solution of the Dirac equations and the solution of an inhomogeneous matrix equation for the meson fields. For the determination of the Coulomb field the Greens function method is used.

  12. Relativistic mean-field study of the properties of Z=117 nuclei and the decay chains of the {sup 293,294}117 isotopes

    SciTech Connect

    Bhuyan, M.; Patra, S. K.; Gupta, Raj K.

    2011-07-15

    We have calculated the binding energy, root-mean-square radius, and quadrupole deformation parameter for the recently synthesized superheavy element Z=117, using the axially deformed relativistic mean-field (RMF) model. The calculation is extended to various isotopes of the Z=117 element, starting from A=286 till A=310. We predict almost spherical structures in the ground state for almost all the isotopes. A shape transition appears at about A=292 from a prolate to an oblate shape structure of the Z=117 nucleus in our mean-field approach. The most stable isotope (largest binding energy per nucleon) is found to be the {sup 288}117 nucleus. Also, the Q{sub {alpha}} values and the half-life T{sub 1/2}{sup {alpha}} for the {alpha}-decay chains of {sup 293}117 and {sup 294}117 are calculated, supporting the magic numbers at N=172 and/or 184.

  13. Tools reference manual for a Requirements Specification Language (RSL), version 2.0

    NASA Technical Reports Server (NTRS)

    Fisher, Gene L.; Cohen, Gerald C.

    1993-01-01

    This report describes a general-purpose Requirements Specification Language, RSL. The purpose of RSL is to specify precisely the external structure of a mechanized system and to define requirements that the system must meet. A system can be comprised of a mixture of hardware, software, and human processing elements. RSL is a hybrid of features found in several popular requirements specification languages, such as SADT (Structured Analysis and Design Technique), PSL (Problem Statement Language), and RMF (Requirements Modeling Framework). While languages such as these have useful features for structuring a specification, they generally lack formality. To overcome the deficiencies of informal requirements languages, RSL has constructs for formal mathematical specification. These constructs are similar to those found in formal specification languages such as EHDM (Enhanced Hierarchical Development Methodology), Larch, and OBJ3.

  14. Adaptive Control Using Residual Mode Filters Applied to Wind Turbines

    NASA Technical Reports Server (NTRS)

    Frost, Susan A.; Balas, Mark J.

    2011-01-01

    Many dynamic systems containing a large number of modes can benefit from adaptive control techniques, which are well suited to applications that have unknown parameters and poorly known operating conditions. In this paper, we focus on a model reference direct adaptive control approach that has been extended to handle adaptive rejection of persistent disturbances. We extend this adaptive control theory to accommodate problematic modal subsystems of a plant that inhibit the adaptive controller by causing the open-loop plant to be non-minimum phase. We will augment the adaptive controller using a Residual Mode Filter (RMF) to compensate for problematic modal subsystems, thereby allowing the system to satisfy the requirements for the adaptive controller to have guaranteed convergence and bounded gains. We apply these theoretical results to design an adaptive collective pitch controller for a high-fidelity simulation of a utility-scale, variable-speed wind turbine that has minimum phase zeros.

  15. Single-proton resonant states and the isospin dependence investigated by Green’s function relativistic mean field theory

    NASA Astrophysics Data System (ADS)

    Sun, T. T.; Niu, Z. M.; Zhang, S. Q.

    2016-08-01

    The relativistic mean field theory formulated with Green’s function method (RMF-GF) is applied to investigate single-proton resonant states and isospin dependence. The calculated energies and widths for the single-proton resonant states in {}120{{Sn}} are in good agreement with previous investigations. The single-proton resonant states of the Sn isotopes and the N = 82 isotones are systematically studied and it is shown that the calculated energies and widths decrease monotonically with the increase of neutron number while increase monotonically with the increase of proton number. To further examine the evolutions of the single-proton resonant states, their dependence on the depth, radius and diffuseness of nuclear potential is investigated with the help of an analytic Woods-Saxon potential, and it is found that the increase of radius plays the most important role in the cross phenomenon appearing in the single-proton resonant states of the Sn isotopes.

  16. Arsenic mobility in the amended mine tailings and its impact on soil enzyme activity.

    PubMed

    Koo, Namin; Lee, Sang-Hwan; Kim, Jeong-Gyu

    2012-06-01

    The objectives of this study were to elucidate the effects of soil amendments [Ferrous sulfate (Fe(II)), red mud, Fe(II) with calcium carbonate (Fe(II)/L) or red mud (RM/F), zero-valent iron (ZVI), furnace slag, spent mushroom waste and by-product fertilizer] on arsenic (As) stabilization and to establish relationships between soil properties, As fractions and soil enzyme activities in amended As-rich gold mine tailings (Kangwon and Keumkey). Following the application of amendments, a sequential extraction test and evaluation of the soil enzyme activities (dehydrogenase and β-glucosidase) were conducted. Weak and negative relationships were observed between water-soluble As fractions (As(WS)) and oxalate extractable iron, while As(WS) was mainly affected by dissolved organic carbon in alkaline tailings sample (Kangwon) and by soil pH in acidic tailings sample (Keumkey). The soil enzyme activities in both tailings were mainly associated with As(WS). Principal component and multiple regression analyses confirmed that As(WS) was the most important factor to soil enzyme activities. However, with some of the treatments in Keumkey, contrary results were observed due to increased water-soluble heavy metals and carbon sources. In conclusion, our results suggest that to simultaneously achieve decreased As(WS) and increased soil enzyme activities, Kangwon tailings should be amended with Fe(II), Fe(II)/L or ZVI, while only ZVI or RM/F would be suitable for Keumkey tailings. Despite the limitations of specific soil samples, this result can be expected to provide useful information on developing a successful remediation strategy of As-contaminated soils. PMID:21850414

  17. Cluster radioactive decay within the preformed cluster model using relativistic mean-field theory densities

    SciTech Connect

    Singh, BirBikram; Patra, S. K.; Gupta, Raj K.

    2010-07-15

    We have studied the (ground-state) cluster radioactive decays within the preformed cluster model (PCM) of Gupta and collaborators [R. K. Gupta, in Proceedings of the 5th International Conference on Nuclear Reaction Mechanisms, Varenna, edited by E. Gadioli (Ricerca Scientifica ed Educazione Permanente, Milano, 1988), p. 416; S. S. Malik and R. K. Gupta, Phys. Rev. C 39, 1992 (1989)]. The relativistic mean-field (RMF) theory is used to obtain the nuclear matter densities for the double folding procedure used to construct the cluster-daughter potential with M3Y nucleon-nucleon interaction including exchange effects. Following the PCM approach, we have deduced empirically the preformation probability P{sub 0}{sup emp} from the experimental data on both the alpha- and exotic cluster-decays, specifically of parents in the trans-lead region having doubly magic {sup 208}Pb or its neighboring nuclei as daughters. Interestingly, the RMF-densities-based nuclear potential supports the concept of preformation for both the alpha and heavier clusters in radioactive nuclei. P{sub 0}{sup a}lpha{sup (emp)} for alpha decays is almost constant (approx10{sup -2}-10{sup -3}) for all the parent nuclei considered here, and P{sub 0}{sup c(emp)} for cluster decays of the same parents decrease with the size of clusters emitted from different parents. The results obtained for P{sub 0}{sup c(emp)} are reasonable and are within two to three orders of magnitude of the well-accepted phenomenological model of Blendowske-Walliser for light clusters.

  18. Validation of OMI UV measurements against ground-based measurements at a station in Kampala, Uganda

    NASA Astrophysics Data System (ADS)

    Muyimbwa, Dennis; Dahlback, Arne; Stamnes, Jakob; Hamre, Børge; Frette, Øyvind; Ssenyonga, Taddeo; Chen, Yi-Chun

    2015-04-01

    We present solar ultraviolet (UV) irradiance data measured with a NILU-UV instrument at a ground site in Kampala (0.31°N, 32.58°E), Uganda for the period 2005-2014. The data were analyzed and compared with UV irradiances inferred from the Ozone Monitoring Instrument (OMI) for the same period. Kampala is located on the shores of lake Victoria, Africa's largest fresh water lake, which may influence the climate and weather conditions of the region. Also, there is an excessive use of worn cars, which may contribute to a high anthropogenic loading of absorbing aerosols. The OMI surface UV algorithm does not account for absorbing aerosols, which may lead to systematic overestimation of surface UV irradiances inferred from OMI satellite data. We retrieved UV index values from OMI UV irradiances and validated them against the ground-based UV index values obtained from NILU-UV measurements. The UV index values were found to follow a seasonal pattern similar to that of the clouds and the rainfall. OMI inferred UV index values were overestimated with a mean bias of about 28% under all-sky conditions, but the mean bias was reduced to about 8% under clear-sky conditions when only days with radiation modification factor (RMF) greater than 65% were considered. However, when days with RMF greater than 70, 75, and 80% were considered, OMI inferred UV index values were found to agree with the ground-based UV index values to within 5, 3, and 1%, respectively. In the validation we identified clouds/aerosols, which were present in 88% of the measurements, as the main cause of OMI inferred overestimation of the UV index.

  19. Origin and dynamics of dissolved and particulate nutrients in a minimally disturbed Mediterranean river with intermittent flow

    NASA Astrophysics Data System (ADS)

    Skoulikidis, Nikolaos; Amaxidis, Yorgos

    2009-06-01

    SummaryHydrological pathways, speciation, and in-stream spatio-temporal variations (including initial flood pulses), along with soil/sediment characteristics, pointed out to the most probable factors and processes driving the origin, levels and dynamics of nutrients in a minimally disturbed Greek temporal river. Nitrogen and phosphorus were predominately found in the organic form and, despite the high suspended sediment transport, in the dissolved phase. Forest soil leaching and erosion fuelled the river with organic nutrients both in the dissolved and particulate phase, especially at the upstream portion of the basin. This part of the basin exhibited "pristine" dissolved nutrient levels (e.g. 30 μg/l DIN, 1.04 μg/l P-PO 4), despite substantial transport through precipitation and subsurface flow, suggesting that certain biogeochemical processes acting in the watershed and in-stream effectively reduce riverine dissolved nutrient concentrations. Intense erosion caused a significant downstream increase of suspended sediments and associated nutrient concentrations. Flushing processes, that were detected even in a monthly base in particular river stretches, enhanced dissolved and particulate nutrient concentrations. Initial flood pulses created "hot moments" chiefly for suspended sediments (RMF during initial flood events reached up to 7) and associated nutrients (e.g. RMF of POC during initial flood events reached up to 32), although flood event sediments presented lower nutrient portions compared to usual sediment transport. Flush peaks of ammonia (max 19 mg/l NH 4) and nitrite (max 42 μg/l NO 2), that surpassed aquatic quality standards, were attributed to rapid mineralization of organic matter upon rewetting and subsequent nitrification. River bed sediments were characterized by organic carbon and nitrogen losses, due to leaching and mineralization processes, and phosphorus retention, thus affecting nutrient ratios and hence photosynthesis in receiving waters.

  20. Therapeutic Efficacy of an Fc-Enhanced TCR-Like Antibody to the Intracellular WT1 Oncoprotein

    PubMed Central

    Veomett, Nicholas; Dao, Tao; Liu, Hong; Xiang, Jingyi; Pankov, Dmitry; Dubrovsky, Leonid; Whitten, Joseph A.; Park, Sun-Mi; Korontsvit, Tatyana; Zakhaleva, Victoria; Casey, Emily; Curcio, Michael; Kharas, Michael G.; O’Reilly, Richard J.; Liu, Cheng; Scheinberg, David A.

    2014-01-01

    Purpose RMFPNAPYL (RMF), a WT1-derived CD8 T cell epitope presented by HLA-A*02:01, is a validated target for T-cell-based immunotherapy. We previously reported ESK1, a high avidity (Kd < 0.2nM), fully-human monoclonal antibody (mAb) specific for the WT1 RMF peptide/HLA-A*02:01 complex, which selectively bound and killed WT1+ and HLA-A*02:01+ leukemia and solid tumor cell lines. Experimental Design We engineered a second-generation mAb, ESKM, to have enhanced antibody dependent cell-mediated cytotoxicity (ADCC) function due to altered Fc glycosylation. ESKM was compared to native ESK1 in binding assays, in vitro ADCC assays, and mesothelioma and leukemia therapeutic models and pharmacokinetic studies in mice. ESKM toxicity was assessed in HLA-A*02:01+ transgenic mice. Results ESK antibodies mediated ADCC against hematopoietic and solid tumor cells at concentrations below 1µg/ml, but ESKM was about 5–10 fold more potent in vitro against multiple cancer cell lines. ESKM was more potent in vivo against JMN mesothelioma, and effective against SET2 AML and fresh ALL xenografts. ESKM had a shortened half-life (4.9 vs 6.5 days), but an identical biodistribution pattern in C57BL6/J mice. At therapeutic doses of ESKM, there was no difference in half-life or biodistribution in HLA-A*02:01+ transgenic mice compared to the parent strain. Importantly, therapeutic doses of ESKM in these mice caused no depletion of total WBCs or hematopoetic stem cells, or pathologic tissue damage. Conclusions The data provide proof of concept that an Fc-enhanced mAb can improve efficacy against a low-density, tumor-specific, peptide/MHC target, and support further development of this mAb against an important intracellular oncogenic protein. PMID:24850840

  1. A Mechanism-Based Approach to Predict the Relative Biological Effectiveness of Protons and Carbon Ions in Radiation Therapy

    SciTech Connect

    Frese, Malte C.; Yu, Victor K.; Stewart, Robert D.; Carlson, David J.

    2012-05-01

    Purpose: The physical and potential biological advantages of proton and carbon ions have not been fully exploited in radiation therapy for the treatment of cancer. In this work, an approach to predict proton and carbon ion relative biological effectiveness (RBE) in a representative spread-out Bragg peak (SOBP) is derived using the repair-misrepair-fixation (RMF) model. Methods and Materials: Formulas linking dose-averaged linear-quadratic parameters to DSB induction and processing are derived from the RMF model. The Monte Carlo Damage Simulation (MCDS) software is used to quantify the effects of radiation quality on the induction of DNA double-strand breaks (DSB). Trends in parameters {alpha} and {beta} for clinically relevant proton and carbon ion kinetic energies are determined. Results: Proton and carbon ion RBE are shown to increase as particle energy, dose, and tissue {alpha}/{beta} ratios decrease. Entrance RBE is {approx}1.0 and {approx}1.3 for protons and carbon ions, respectively. For doses in the range of 0.5 to 10 Gy, proton RBE ranges from 1.02 (proximal edge) to 1.4 (distal edge). Over the same dose range, the RBE for carbon ions ranges from 1.5 on the proximal edge to 6.7 on the distal edge. Conclusions: The proposed approach is advantageous because the RBE for clinically relevant particle distributions is guided by well-established physical and biological (track structure) considerations. The use of an independently tested Monte Carlo model to predict the effects of radiation quality on DSB induction also minimizes the number of ad hoc biological parameters that must be determined to predict RBE. Large variations in predicted RBE across an SOBP may produce undesirable biological hot and cold spots. These results highlight the potential for the optimization of physical dose for a uniform biological effect.

  2. Control of Meridional Flow by a Non-Uniform Rotational Magnetic Field

    NASA Technical Reports Server (NTRS)

    Mazuruk, Konstantin; Ramachandran, Narayanan

    1999-01-01

    The diffusive mass transfer of species during crystal growth in vertical ampoules is significantly affected by fluid flow in the liquid mother phase (melt). For electrically conductive melts, an elegant way of remotely inducing and controlling this flow is by utilizing a uniform rotational magnetic field (RMF) in the transverse direction. It induces an azimuthal flow which tends to homogenize the thermal and solutal fields. The rotating field also reduces the diffusion boundary layer, stabilizes temperature fluctuations, and promotes better overall crystal growth. For moderate strengths of the applied magnetic field (2-20 m Tesla) with frequencies of up to 400 Hz, the induced secondary meridional flow becomes significant. It typically consists of one roll at the bottom of the liquid column and a second roll (vortex) at the top. The flow along the centerline (ampoule axis) is directed from the growing solid (interface) towards the liquid (melt). In case of convex interfaces (e.g. in floating zone crystal growth) such flow behavior is beneficial since it suppresses diffusion at the center. However, for concave interfaces (e.g. vertical Bridgman crystal growth) such a flow tends to exacerbate the situation in making the interface shape more concave. It would be beneficial to have some control of this meridional flow- for example, a single recirculating cell with controllable direction and flow magnitude will make this technique even more attractive for crystal growth. Such flow control is a possibility if a non-uniform PNE field is utilized for this purpose. Although this idea has been proposed earlier, it has not been conclusively demonstrated so far. In this work, we derive the governing equations for the fluid dynamics for such a system and obtain solutions for a few important cases. Results from parallel experimental measurements of fluid flow in a mercury column subjected to non-uniform RMF will also be presented.

  3. Development of a versatile XRF scanner for the elemental imaging of paintworks

    NASA Astrophysics Data System (ADS)

    Ravaud, E.; Pichon, L.; Laval, E.; Gonzalez, V.; Eveno, M.; Calligaro, T.

    2016-01-01

    Scanning XRF is a powerful elemental imaging technique introduced at the synchrotron that has recently been transposed to laboratory. The growing interest in this technique stems from its ability to collect images reflecting pigment distribution within large areas on artworks by means of their elemental signature. In that sense, scanning XRF appears highly complementary to standard imaging techniques (Visible, UV, IR photography and X-ray radiography). The versatile XRF scanner presented here has been designed and built at the C2RMF in response to specific constraints: transportability, cost-effectiveness and ability to scan large areas within a single working day. The instrument is based on a standard X-ray generator with sub-millimetre collimated beam and a SDD-based spectrometer to collected X-ray spectra. The instrument head is scanned in front of the painting by means of motorised movements to cover an area up to 300 × 300 mm2 with a resolution of 0.5 mm (600 × 600 pixels). The 15-kg head is mounted on a stable photo stand for rapid positioning on paintworks and maintains a free side-access for safety; it can also be attached to a lighter tripod for field measurements. Alignment is achieved with a laser pointer and a micro-camera. With a scanning speed of 5 mm/s and 0.1 s/point, elemental maps are collected in 10 h, i.e. a working day. The X-ray spectra of all pixels are rapidly processed using an open source program to derive elemental maps. To illustrate the capabilities of this instrument, this contribution presents the results obtained on the Belle Ferronnière painted by Leonardo da Vinci (1452-1519) and conserved in the Musée du Louvre, prior to its restoration at the C2RMF.

  4. Dual-plane ultrasound flow measurements in liquid metals

    NASA Astrophysics Data System (ADS)

    Büttner, Lars; Nauber, Richard; Burger, Markus; Räbiger, Dirk; Franke, Sven; Eckert, Sven; Czarske, Jürgen

    2013-05-01

    An ultrasound measurement system for dual-plane, two-component flow velocity measurements especially in opaque liquids is presented. Present-day techniques for measuring local flow structures in opaque liquids disclose considerable drawbacks concerning line-wise measurement of single ultrasound probes. For studying time-varying flow patterns, conventional ultrasound techniques are either limited by time-consuming mechanical traversing or by the sequential operation of single probes. The measurement system presented within this paper employs four transducer arrays with a total of 100 single elements which allows for flow mapping without mechanical traversing. A high frame rate of several 10 Hz has been achieved due to an efficient parallelization scheme using time-division multiplexing realized by a microcontroller-based electronic switching matrix. The functionality and capability of the measurement system are demonstrated on a liquid metal flow at room temperature inside a cube driven by a rotating magnetic field (RMF). For the first time, the primary and the secondary flow have been studied in detail and simultaneously using a configuration with two crossed measurement planes. The experimental data confirm predictions made by numeric simulation. After a sudden switching on of the RMF, inertial oscillations of the secondary flow were observed by means of a time-resolved measurement with a frame rate of 3.4 Hz. The experiments demonstrate that the presented measurement system is able to investigate complex and transient flow structures in opaque liquids. Due to its ability to study the temporal evolution of local flow structures, the measurement system could provide considerable progress for fluid dynamics research, in particular for applications in the food industry or liquid metal technologies.

  5. Nucleon-nucleon momentum-correlation function as a probe of the density distribution of valence neutrons in neutron-rich nuclei

    NASA Astrophysics Data System (ADS)

    Cao, X. G.; Cai, X. Z.; Ma, Y. G.; Fang, D. Q.; Zhang, G. Q.; Guo, W.; Chen, J. G.; Wang, J. S.

    2012-10-01

    Proton-neutron, neutron-neutron, and proton-proton momentum-correlation functions (Cpn,Cnn, and Cpp) are systematically investigated for 15C and other C-isotope-induced collisions at different entrance channel conditions within the framework of the isospin-dependent quantum-molecular-dynamics model complemented by the correlation after burner (crab) computation code. 15C is a prime exotic nucleus candidate due to the weakly bound valence neutron coupling with closed-neutron-shell nucleus 14C. To study density dependence of the correlation function by removing the isospin effect, the initialized 15C projectiles are sampled from two kinds of density distribution from the relativistic mean-field (RMF) model in which the valence neutron of 15C is populated in both 1d5/2 and 2s1/2 states, respectively. The results show that the density distributions of the valence neutron significantly influence the nucleon-nucleon momentum-correlation function at large impact parameters and high incident energies. The extended density distribution of the valence neutron largely weakens the strength of the correlation function. The size of the emission source is extracted by fitting the correlation function by using the Gaussian source method. The emission source size as well as the size of the final-state phase space are larger for projectile samplings from more extended density distributions of the valence neutron, which corresponds to the 2s1/2 state in the RMF model. Therefore, the nucleon-nucleon momentum-correlation function can be considered as a potentially valuable tool to diagnose exotic nuclear structures, such as the skin and halo.

  6. Neuropatía persistente aumenta el riesgo de caídas entre supervivientes de cáncer

    Cancer.gov

    Muchas mujeres supervivientes de cáncer tienen problemas de movilidad y de otras funciones físicas como resultado de la neuropatía periférica persistente causada por el tratamiento de quimioterapia, según un estudio nuevo.

  7. Familiares a cargo de pacientes de cáncer (PDQ®)—Versión para pacientes

    Cancer.gov

    Sumario informativo revisado por expertos acerca de los desafíos que enfrentan los familiares a cargo de los pacientes con cáncer. Este resumen se centra en las funciones típicas y las inquietudes de las personas a cargo del paciente y en las intervenciones útiles para esas personas.

  8. ROTARY FILTER FINES TESTING FOR SMALL COLUMN ION EXCHANGE

    SciTech Connect

    Herman, D.

    2011-08-03

    SRNL was requested to quantify the amount of 'fines passage' through the 0.5 micron membranes currently used for the rotary microfilter (RMF). Testing was also completed to determine if there is any additional benefit to utilizing a 0.1 micron filter to reduce the amount of fines that could pass through the filter. Quantifying of the amount of fines that passed through the two sets of membranes that were tested was accomplished by analyzing the filtrate by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) for titanium. Even with preparations to isolate the titanium, all samples returned results of less than the instrument's detection limit of 0.184 mg/L. Test results show that the 0.5 micron filters produced a significantly higher flux while showing a negligible difference in filtrate clarity measured by turbidity. The first targeted deployment of the RMF is with the Small Column Ion Exchange (SCIX) at the Savannah River Site (SRS). SCIX uses crystalline silicotitanate (CST) to sorb cesium to decontaminate a clarified salt solution. The passage of fine particles through the filter membranes in sufficient quantities has the potential to impact the downstream facilities. To determine the amount of fines passage, a contract was established with SpinTek Filtration to operate a 3-disk pilot scale unit with prototypic filter disk and various feeds and two different filter disk membranes. SpinTek evaluated a set of the baseline 0.5 micron filter disks as well as a set of 0.1 micron filter disks to determine the amount of fine particles that would pass the membrane and to determine the flux each set produced. The membrane on both disk sets is manufactured by the Pall Corporation (PMM 050). Each set of disks was run with three feed combinations: prototypically ground CST, CST plus monosodium titanate (MST), and CST, MST, plus Sludge Batch 6 (SB6) simulant. Throughout the testing, samples of the filtrate were collected, measured for turbidity, and sent back

  9. Biologically optimized helium ion plans: calculation approach and its in vitro validation

    NASA Astrophysics Data System (ADS)

    Mairani, A.; Dokic, I.; Magro, G.; Tessonnier, T.; Kamp, F.; Carlson, D. J.; Ciocca, M.; Cerutti, F.; Sala, P. R.; Ferrari, A.; Böhlen, T. T.; Jäkel, O.; Parodi, K.; Debus, J.; Abdollahi, A.; Haberer, T.

    2016-06-01

    Treatment planning studies on the biological effect of raster-scanned helium ion beams should be performed, together with their experimental verification, before their clinical application at the Heidelberg Ion Beam Therapy Center (HIT). For this purpose, we introduce a novel calculation approach based on integrating data-driven biological models in our Monte Carlo treatment planning (MCTP) tool. Dealing with a mixed radiation field, the biological effect of the primary 4He ion beams, of the secondary 3He and 4He (Z  =  2) fragments and of the produced protons, deuterons and tritons (Z  =  1) has to be taken into account. A spread-out Bragg peak (SOBP) in water, representative of a clinically-relevant scenario, has been biologically optimized with the MCTP and then delivered at HIT. Predictions of cell survival and RBE for a tumor cell line, characterized by {{(α /β )}\\text{ph}}=5.4 Gy, have been successfully compared against measured clonogenic survival data. The mean absolute survival variation ({μΔ \\text{S}} ) between model predictions and experimental data was 5.3%  ±  0.9%. A sensitivity study, i.e. quantifying the variation of the estimations for the studied plan as a function of the applied phenomenological modelling approach, has been performed. The feasibility of a simpler biological modelling based on dose-averaged LET (linear energy transfer) has been tested. Moreover, comparisons with biophysical models such as the local effect model (LEM) and the repair-misrepair-fixation (RMF) model were performed. {μΔ \\text{S}} values for the LEM and the RMF model were, respectively, 4.5%  ±  0.8% and 5.8%  ±  1.1%. The satisfactorily agreement found in this work for the studied SOBP, representative of clinically-relevant scenario, suggests that the introduced approach could be applied for an accurate estimation of the biological effect for helium ion radiotherapy.

  10. Biologically optimized helium ion plans: calculation approach and its in vitro validation.

    PubMed

    Mairani, A; Dokic, I; Magro, G; Tessonnier, T; Kamp, F; Carlson, D J; Ciocca, M; Cerutti, F; Sala, P R; Ferrari, A; Böhlen, T T; Jäkel, O; Parodi, K; Debus, J; Abdollahi, A; Haberer, T

    2016-06-01

    Treatment planning studies on the biological effect of raster-scanned helium ion beams should be performed, together with their experimental verification, before their clinical application at the Heidelberg Ion Beam Therapy Center (HIT). For this purpose, we introduce a novel calculation approach based on integrating data-driven biological models in our Monte Carlo treatment planning (MCTP) tool. Dealing with a mixed radiation field, the biological effect of the primary (4)He ion beams, of the secondary (3)He and (4)He (Z  =  2) fragments and of the produced protons, deuterons and tritons (Z  =  1) has to be taken into account. A spread-out Bragg peak (SOBP) in water, representative of a clinically-relevant scenario, has been biologically optimized with the MCTP and then delivered at HIT. Predictions of cell survival and RBE for a tumor cell line, characterized by [Formula: see text] Gy, have been successfully compared against measured clonogenic survival data. The mean absolute survival variation ([Formula: see text]) between model predictions and experimental data was 5.3%  ±  0.9%. A sensitivity study, i.e. quantifying the variation of the estimations for the studied plan as a function of the applied phenomenological modelling approach, has been performed. The feasibility of a simpler biological modelling based on dose-averaged LET (linear energy transfer) has been tested. Moreover, comparisons with biophysical models such as the local effect model (LEM) and the repair-misrepair-fixation (RMF) model were performed. [Formula: see text] values for the LEM and the RMF model were, respectively, 4.5%  ±  0.8% and 5.8%  ±  1.1%. The satisfactorily agreement found in this work for the studied SOBP, representative of clinically-relevant scenario, suggests that the introduced approach could be applied for an accurate estimation of the biological effect for helium ion radiotherapy. PMID:27203864

  11. Triaxially deformed relativistic point-coupling model for Λ hypernuclei: A quantitative analysis of the hyperon impurity effect on nuclear collective properties

    NASA Astrophysics Data System (ADS)

    Xue, W. X.; Yao, J. M.; Hagino, K.; Li, Z. P.; Mei, H.; Tanimura, Y.

    2015-02-01

    Background: The impurity effect of hyperons on atomic nuclei has received a renewed interest in nuclear physics since the first experimental observation of appreciable reduction of E 2 transition strength in low-lying states of the hypernucleus Λ7Li . Many more data on low-lying states of Λ hypernuclei will be measured soon for s d -shell nuclei, providing good opportunities to study the Λ impurity effect on nuclear low-energy excitations. Purpose: We carry out a quantitative analysis of the Λ hyperon impurity effect on the low-lying states of s d -shell nuclei at the beyond-mean-field level based on a relativistic point-coupling energy density functional (EDF), considering that the Λ hyperon is injected into the lowest positive-parity (Λs) and negative-parity (Λp) states. Method: We adopt a triaxially deformed relativistic mean-field (RMF) approach for hypernuclei and calculate the Λ binding energies of hypernuclei as well as the potential-energy surfaces (PESs) in the (β ,γ ) deformation plane. We also calculate the PESs for the Λ hypernuclei with good quantum numbers by using a microscopic particle rotor model (PRM) with the same relativistic EDF. The triaxially deformed RMF approach is further applied in order to determine the parameters of a five-dimensional collective Hamiltonian (5DCH) for the collective excitations of triaxially deformed core nuclei. Taking 25,27Mg Λ and Si31Λ as examples, we analyze the impurity effects of Λs and Λp on the low-lying states of the core nuclei. Results: We show that Λs increases the excitation energy of the 21+ state and decreases the E 2 transition strength from this state to the ground state by 12 %to17 % . On the other hand, Λp tends to develop pronounced energy minima with larger deformation, although it modifies the collective parameters in such a way that the collectivity of the core nucleus can be either increased or decreased. Conclusions: The quadrupole deformation significantly affects the

  12. Controls for space structures

    NASA Technical Reports Server (NTRS)

    Balas, Mark

    1991-01-01

    Assembly and operation of large space structures (LSS) in orbit will require robot-assisted docking and berthing of partially-assembled structures. These operations require new solutions to the problems of controls. This is true because of large transient and persistent disturbances, controller-structure interaction with unmodeled modes, poorly known structure parameters, slow actuator/sensor dynamical behavior, and excitation of nonlinear structure vibrations during control and assembly. For on-orbit assembly, controllers must start with finite element models of LSS and adapt on line to the best operating points, without compromising stability. This is not easy to do, since there are often unmodeled dynamic interactions between the controller and the structure. The indirect adaptive controllers are based on parameter estimation. Due to the large number of modes in LSS, this approach leads to very high-order control schemes with consequent poor stability and performance. In contrast, direct model reference adaptive controllers operate to force the LSS to track the desirable behavior of a chosen model. These schemes produce simple control algorithms which are easy to implement on line. One problem with their use for LSS has been that the model must be the same dimension as the LSS - i.e., quite large. A control theory based on the command generator tracker (CGT) ideas of Sobel, Mabins, Kaufman and Wen, Balas to obtain very low-order models based on adaptive algorithms was developed. Closed-loop stability for both finite element models and distributed parameter models of LSS was proved. In addition, successful numerical simulations on several LSS databases were obtained. An adaptive controller based on our theory was also implemented on a flexible robotic manipulator at Martin Marietta Astronautics. Computation schemes for controller-structure interaction with unmodeled modes, the residual mode filters or RMF, were developed. The RMF theory was modified to compensate

  13. Crates: High-Level I/O Interface for Scripting Languages

    NASA Astrophysics Data System (ADS)

    Cresitello-Dittmar, M.; Burke, D.; Doe, S.; Evans, I.; Evans, J.; Germain, G.; Lyn, J.

    2007-10-01

    Crates is a new software package being developed by the Chandra X-Ray Center (CXC) to provide a high level I/O interface for use within various scripting environments. It consists of a set of classes and methods which allow a user to easily access and manipulate general data files as well as specialized classes for specific data products (PHA Type I & II, RMF, ARF, etc.). CRATES also provides convenient access to metadata information, such as WCS transforms and DM subspace information which may be associated with a table column or image. The core library is written in C++ and utilizes the CXC DataModel (DM) library, which provides I/O support for the Chandra Data Analysis software, and is designed to be extensible to multiple scripting environments. We provide a set of Python wrappers and functionality from within the SLang environment via PySL. The interface has a common look and feel with the CIAO application packages Sherpa, a general purpose fitting and modeling application, and ChIPS, the Chandra Imaging and Plotting System.

  14. The bacterial translation stress response

    PubMed Central

    Starosta, Agata L.; Lassak, Jürgen; Jung, Kirsten; Wilson, Daniel N.

    2014-01-01

    Throughout their life, bacteria need to sense and respond to environmental stress. Thus, such stress responses can require dramatic cellular reprogramming, both at the transcriptional as well as the translational level. This review focuses on the protein factors that interact with the bacterial translational apparatus in order to respond to and cope with different types of environmental stress. For example, the stringent factor RelA interacts with the ribosome to generate ppGpp under nutrient deprivation, whereas a variety of factors have been identified that bind to the ribosome under unfavorable growth conditions to shut-down (RelE, pY, RMF, HPF and EttA) or re-program (MazF, EF4 and BipA) translation. Additional factors have been identified that rescue ribosomes stalled due to stress-induced mRNA truncation (tmRNA, ArfA, ArfB), translation of unfavorable protein sequences (EF-P), heat shock induced subunit dissociation (Hsp15) or antibiotic inhibition (TetM, FusB). Understanding the mechanism of how the bacterial cell responds to stress will not only provide fundamental insight into translation regulation, but will also be an important step to identifying new targets for the development of novel antimicrobial agents. PMID:25135187

  15. Kaon Condensation and Lambda-Nucleon Loop in the Relativistic Mean-Field Approach

    SciTech Connect

    Tomoyuki Maruyama; Takumi Muto; Toshitaka Tatsumi; Kazuo Tsushima; Anthony W. Thomas

    2005-02-24

    The possibility of kaon condensation in high-density symmetric nuclear matter is investigated including both s- and p-wave kaon-baryon interactions within the relativistic mean-field (RMF) theory. Above a certain density, we have a collective K{sub s} state carrying the same quantum numbers as the antikaon. The appearance of the K{sub s} state is caused by the time component of the axial-vector interaction between kaons and baryons. It is shown that the system becomes unstable with respect to condensation of K-Kbar{sub s} pairs. We consider how the effective baryon masses affect the kaon self-energy coming from the time component of the axial-vector interaction. Also, the role of the spatial component of the axial-vector interaction on the possible existence of the collective kaonic states is discussed in connection with Lambda-mixing effects in the ground state of high-density matter. Implications of K-Kbar{sub s} condensation for high-energy heavy-ion collisions are briefly mentioned.

  16. Food control from farm to fork: implementing the standards of Codex and the OIE.

    PubMed

    Hathaway, S C

    2013-08-01

    The Codex Alimentarius (Codex) international food standards help to ensure food safety and promote fair practices in the international food trade. Implementing these standards using a risk management framework (RMF) approach to decision-making is an increasingly common aspect of the food control programmes of national governments. The Codex Alimentarius Commission (CAC) provides guidance at both the system and food commodity levels. In the case of zoonoses, similarities in the risk analysis methodologies used to underpin standard setting by the CAC and the World Organisation for Animal Health (OIE) are highly enabling of integrated food control systems. The CAC and the OIE are increasingly working together to develop their respective standards for foodborne zoonoses and other hazards so that they are non-duplicative, cohesive and utilise the whole food chain. There is a clear need for effective integration of food safety and animal health monitoring and surveillance information to better control foodborne zoonoses. This is increasingly supported by Codex and OIE standards working together in a variety of ways and realisation of benefits is highly dependent on coordination and sharing of information between Competent Authorities and other food safety stakeholders at the national level. PMID:24547651

  17. Diminished organelle motion in murine Kupffer cells during the erythrocytic stage of malaria

    PubMed Central

    Bellows, Charles F.; Molina, Ramon M.; Brain, Joseph D.

    2011-01-01

    Parasitized erythrocytes are ingested by murine hepatic macrophages during malaria infection. We non-invasively monitored how this altered the motion of intracellular phagosomes in Kupffer cells using magnetometry. Submicrometric γFe2O3 particles were injected prior to malaria infection. They were cleared from the blood, primarily by Kupffer cells, and retained within their phagosomes. The mice were periodically magnetized. After removing this external magnet, the aligned iron particles created a remnant magnetic field (RMF) which then decayed (relaxation), reflecting the motion of particle-containing phagosomes. After baseline measurements of relaxation, the mice were injected intravenously with Plasmodium chabaudi-parasitized or normal murine red blood cells (RBCs). During the next 15 days, relaxation measurements, parasitaemia and haematocrit values were monitored. At 6 days post injection with 3 × 107 parasitized RBCs, relaxation rates had decreased. At this time, all mice had parasitaemias greater than 58 per cent and haematocrits less than 20 per cent. At day 7, while the parasitaemias were declining, the rate of relaxation continued to decrease. Throughout the experiment, relaxation remained constant in animals injected with normal RBCs. Electron microscopy revealed Kupffer cells filled with damaged and parasitized erythrocytes, and haemoglobin degradation pigment. We conclude that ingestion and metabolism of parasitized erythrocytes by liver macrophages during malaria infection decreases their organelle motion with likely consequences of compromised host defences. PMID:21068031

  18. Package for Interactive Analysis of Line Emission (Analysis of UV-X-Ray High-Resolution Emission Spectra)

    NASA Technical Reports Server (NTRS)

    Kashyap, Vinay; Hunter, Paul (Technical Monitor)

    2003-01-01

    PINTofALE is an IDL based package to analyze high-resolution grating spectra. The first version was made available to the public on 3 February 2001. Since then we have carried out numerous changes, and the current release is version 1.5, released on 9 October 2002. The changes include upgrades to handle higher versions of IDL, the new version of the CHIANTI database (v4), major enhancements in user-friendliness, improved handling of response matrices, the ability to handle 24-bit color, access to the Atomic Plasma Emission Database (APED), and beta releases of Markov Chain Monte Carlo (MCMC) based DEM fitting routines. Plans for the future include: inclusion of MCMC techniques in the fitting programs, enhanced graphics capabilities, an overhaul of the line and continuum database structure, and bug fixes. In September 2002, we hired a data analyst (LiWei Lin) to work on PINTofALE. Mr.Lin is concentrating on incorporating MCMC as well as simpler Monte-Carlo techniques, fast RMF convolution, etc., into the code base, as well as reviewing the existing documentation and searching for bugs. A detailed description of the package, together with fairly detailed documentation, example walks-throughs, and downloadable tar files, are available on-line from http://hea-www. harvard.edu/PINTofALE/

  19. Calculations on decay rates of various proton emissions

    NASA Astrophysics Data System (ADS)

    Qian, Yibin; Ren, Zhongzhou

    2016-03-01

    Proton radioactivity of neutron-deficient nuclei around the dripline has been systematically studied within the deformed density-dependent model. The crucial proton-nucleus potential is constructed via the single-folding integral of the density distribution of daughter nuclei and the effective M3Y nucleon-nucleon interaction or the proton-proton Coulomb interaction. After the decay width is obtained by the modified two-potential approach, the final decay half-lives can be achieved by involving the spectroscopic factors from the relativistic mean-field (RMF) theory combined with the BCS method. Moreover, a simple formula along with only one adjusted parameter is tentatively proposed to evaluate the half-lives of proton emitters, where the introduction of nuclear deformation is somewhat discussed as well. It is found that the calculated results are in satisfactory agreement with the experimental values and consistent with other theoretical studies, indicating that the present approach can be applied to the case of proton emission. Predictions on half-lives are made for possible proton emitters, which may be useful for future experiments.

  20. Ribosome Hibernation Facilitates Tolerance of Stationary-Phase Bacteria to Aminoglycosides

    PubMed Central

    McKay, Susannah L.

    2015-01-01

    Upon entry into stationary phase, bacteria dimerize 70S ribosomes into translationally inactive 100S particles by a process called ribosome hibernation. Previously, we reported that the hibernation-promoting factor (HPF) of Listeria monocytogenes is required for 100S particle formation and facilitates adaptation to a number of stresses. Here, we demonstrate that HPF is required for the high tolerance of stationary-phase cultures to aminoglycosides but not to beta-lactam or quinolone antibiotics. The sensitivity of a Δhpf mutant to gentamicin was suppressed by the bacteriostatic antibiotics chloramphenicol and rifampin, which inhibit translation and transcription, respectively. Disruption of the proton motive force by the ionophore carbonyl cyanide m-chlorophenylhydrazone or mutation of genes involved in respiration also suppressed the sensitivity of the Δhpf mutant. Accordingly, Δhpf mutants had aberrantly high levels of ATP and reducing equivalents during prolonged stationary phase. Analysis of bacterial uptake of fluorescently labeled gentamicin demonstrated that the Δhpf mutant harbored increased intracellular levels of the drug. Finally, deletion of the main ribosome hibernation factor of Escherichia coli, ribosome modulation factor (rmf), rendered these bacteria susceptible to gentamicin. Taken together, these data suggest that HPF-mediated ribosome hibernation results in repression of the metabolic activity that underlies aminoglycoside tolerance. HPF is conserved in nearly every bacterial pathogen, and the role of ribosome hibernation in antibiotic tolerance may have clinical implications. PMID:26324267

  1. Relativistic mean field model based on realistic nuclear forces

    SciTech Connect

    Hirose, S.; Serra, M.; Ring, P.; Otsuka, T.; Akaishi, Y.

    2007-02-15

    In order to predict properties of asymmetric nuclear matter, we construct a relativistic mean field (RMF) model consisting of one-meson exchange (OME) terms and point coupling (PC) terms. In order to determine the density dependent parameters of this model, we use properties of isospin symmetric nuclear matter in combination with the information on nucleon-nucleon scattering data, which are given in the form of the density dependent G-matrix derived from Brueckner calculations based on the Tamagaki potential. We show that the medium- and long-range components of this G-matrix can be described reasonably well by our effective OME interaction. In order to take into account the short-range part of the nucleon-nucleon interaction, which cannot be described well in this manner, a point coupling term is added. Its analytical form is taken from a model based on chiral perturbation theory. It contains only one additional parameter, which does not depend on the density. It is, together with the parameters of the OME potentials adjusted to the equation of state of symmetric nuclear matter. We apply this model for the investigation of asymmetric nuclear matter and find that the results for the symmetry energy as well as for the equation of state of pure neutron matter are in good agreement with either experimental data or with presently adopted theoretical predictions. In order to test the model at higher density, we use its equation of state for an investigation of properties of neutron stars.

  2. Selection in a fluctuating environment and the evolution of sexual dimorphism in the seed beetle Callosobruchus maculatus.

    PubMed

    Hallsson, L R; Björklund, M

    2012-08-01

    Temperature changes in the environment, which realistically include environmental fluctuations, can create both plastic and evolutionary responses of traits. Sexes might differ in either or both of these responses for homologous traits, which in turn has consequences for sexual dimorphism and its evolution. Here, we investigate both immediate changes in and the evolution of sexual dimorphism in response to a changing environment (with and without fluctuations) using the seed beetle Callosobruchus maculatus. We investigate sex differences in plasticity and also the genetic architecture of body mass and developmental time dimorphism to test two existing hypotheses on sex differences in plasticity (adaptive canalization hypothesis and condition dependence hypothesis). We found a decreased sexual size dimorphism in higher temperature and that females responded more plastically than males, supporting the condition dependence hypothesis. However, selection in a fluctuating environment altered sex-specific patterns of genetic and environmental variation, indicating support for the adaptive canalization hypothesis. Genetic correlations between sexes (r(MF) ) were affected by fluctuating selection, suggesting facilitated independent evolution of the sexes. Thus, the selective past of a population is highly important for the understanding of the evolutionary dynamics of sexual dimorphism. PMID:22594940

  3. Halo or skin in the excited states of some light mirror nuclei

    NASA Astrophysics Data System (ADS)

    Chen, J. G.; Cai, X. Z.; Shen, W. Q.; Ma, Y. G.; Ren, Z. Z.; Zhang, H. Y.; Jiang, W. Z.; Zhong, C.; Wei, Y. B.; Guo, W.; Zhou, X. F.; Wang, K.; Ma, G. L.

    2005-01-01

    The properties of three pairs of mirror nuclei 13N- 13C, 15N- 15O and 21Na- 21Ne (these mirror nuclei are all made of a good inert core plus an unpaired valence nucleon) are investigated by using the nonlinear relativistic mean-field (RMF) theory. It is found that the calculated binding energies with two different parameter sets are very close to the experimental ones for both the ground states and the excited states except for the large deformed nuclei. The calculations show that the 2 s1/2 excited states of 15N and of 21Na are both weakly bound with a proton halo and a proton skin (or a pigmy proton skin), respectively. In addition, the 1 d5/2 excited state of 13C and the 2 s1/2 excited state of 15O are also weakly bound with a neutron skin, respectively. The ratio of the valence nucleon radius to matter radius is deduced and it can be regarded as an additional criterion for the existence of exotic structure. The unbound 2 s1/2 and 1 d5/2 excited states of 13N are also discussed.

  4. Influence of pions on the hadron-quark phase transition

    SciTech Connect

    Lourenco, O.; Dutra, M.; Frederico, T.; Malheiro, M.; Delfino, A.

    2013-05-06

    In this work we present the features of the hadron-quark phase transition diagrams in which the pions are included in the system. To construct such diagrams we use two different models in the description of the hadronic and quark sectors. At the quark level, we consider two distinct parametrizations of the Polyakov-Nambu-Jona-Lasinio (PNJL) models. In the hadronic side, we use a well known relativistic mean-field (RMF) nonlinear Walecka model. We show that the effect of the pions on the hadron-quark phase diagrams is to move the critical end point (CEP) of the transitions lines. Such an effect also depends on the value of the critical temperature (T{sub 0}) in the pure gauge sector used to parametrize the PNJL models. Here we treat the phase transitions using two values for T{sub 0}, namely, T{sub 0}= 270 MeV and T{sub 0}= 190 MeV. The last value is used to reproduce lattice QCD data for the transition temperature at zero chemical potential.

  5. Influence of Entropy on Composition and Structure of Massive Protoneutron Stars

    NASA Astrophysics Data System (ADS)

    Hong, Bin; Jia, Huan-Yu; Mu, Xue-Ling; Zhou, Xia

    2016-08-01

    Adjusting the suitable coupling constants in relativistic mean Geld (RMF) theory and focusing on thermal effect of an entropy per baryon (S) from 0 to 3, we investigate the composition and structure of massive protoneutron stars corresponding PSR J1614-2230 and PSR J0348+0432. It is found that massive protoneutron stars (PNSs) have more hyperons than cold neutron stars. The entropy per baryon will stiffen the equation of state, and the influence on the pressure is more obvious at low density than high density, while the influence on the energy density is more obvious at high density than low density. It is found that higher entropy will give higher maximum mass, higher central temperature and lower central density. The entropy per baryon changes from 0 to 3, the radius of a PNS corresponding PSR J0348+0432 will increase from 12.86 km to 19.31 km and PSR J1612-2230 will increase from 13.03 km to 19.93 km. The entropy per baryon will raise the central temperature of massive PNSs in higher entropy per baryon, but the central temperature of massive PNSs maybe keep unchanged in lower entropy per baryon. The entropy per baryon will increase the moment of inertia of a massive protoneutron star, while decrease gravitational redshift of a massive neutron star. Supported by National Natural Science Foundation of China under Grant No. 11175147

  6. MAVEN Information Security Governance, Risk Management, and Compliance (GRC): Lessons Learned

    NASA Technical Reports Server (NTRS)

    Takamura, Eduardo; Gomez-Rosa, Carlos A.; Mangum, Kevin; Wasiak, Fran

    2014-01-01

    As the first interplanetary mission managed by the NASA Goddard Space Flight Center, the Mars Atmosphere and Volatile EvolutioN (MAVEN) had three IT security goals for its ground system: COMPLIANCE, (IT) RISK REDUCTION, and COST REDUCTION. In a multiorganizational environment in which government, industry and academia work together in support of the ground system and mission operations, information security governance, risk management, and compliance (GRC) becomes a challenge as each component of the ground system has and follows its own set of IT security requirements. These requirements are not necessarily the same or even similar to each other's, making the auditing of the ground system security a challenging feat. A combination of standards-based information security management based on the National Institute of Standards and Technology (NIST) Risk Management Framework (RMF), due diligence by the Mission's leadership, and effective collaboration among all elements of the ground system enabled MAVEN to successfully meet NASA's requirements for IT security, and therefore meet Federal Information Security Management Act (FISMA) mandate on the Agency. Throughout the implementation of GRC on MAVEN during the early stages of the mission development, the Project faced many challenges some of which have been identified in this paper. The purpose of this paper is to document these challenges, and provide a brief analysis of the lessons MAVEN learned. The historical information documented herein, derived from an internal pre-launch lessons learned analysis, can be used by current and future missions and organizations implementing and auditing GRC.

  7. Public Release of a One Dimensional Version of the Photon Clean Method (PCM1D)

    NASA Astrophysics Data System (ADS)

    Carpenter, Matthew H.; Jernigan, J. G.

    2006-09-01

    We announce the public release of a one dimensional version of the Photon Clean Method (PCM1D). This code is in the general class of "inverse Monte Carlo" methods and is specifically designed to interoperate with the public analysis tools available from the Chandra Science Center and the HEASARC. The tool produces models of event based data on a photon by photon basis. The instrument models are based on the standard ARF and RMF fits files. The resulting models have a high number of degrees of freedom of order the number of photons detected providing an alternative analysis compared to the usual method of fitting models with only a few parameters. The original work on this method is described in ADASS 1996 (Jernigan and Vezie). We thank H. Tananbaum and J. McDowell of the Chandra Science Center, S. Kahn, the RGS/XMM-Newton US team leader, and W. Craig and S. Labov of the I Division of LLNL for their support for the development of the PCM concept. We thank P. Beiersdorfer and the EBIT team for the support to develop the first public version of PCM1D.

  8. Neutron density distributions analyzed in terms of relativistic impulse approximation for nickel isotopes

    NASA Astrophysics Data System (ADS)

    Kaki, Kaori

    2015-03-01

    Observables of proton elastic scattering from nickel isotopes (48-82Ni) are calculated based on relativistic impulse approximation (RIA), and nuclear density distributions are provided by relativistic mean-field (RMF) calculations. Contributions of a medium effect and multiple scattering to observables are evaluated and shown to be small at incident proton energies from 200 MeV through 500 MeV so that it is confirmed to perform a model analysis based on the fundamental RIA calculation. For 58,60,62,64Ni isotopes, are considered proton distributions which are obtained by means of unfolding the charge form factor of proton from charge densities determined by the experiments of electron scattering. Through comparisons between results for the different proton densities, contributions of proton form factor to proton distributions and to elastic scattering observables at 300 MeV are discussed. It is shown that the neutron distribution is determined from the restricted observables, reaction cross-section and the first dip of differential cross-section, based on a model analysis of Woods-Saxon distribution in the case of 64Ni target at 300 MeV. Contributions of tensor density and empirical proton density are shown to obtaining the neutron distribution with the model analysis. Compared with the similar studies for 40,60Ca and 208Pb, problems of the model analysis, which arise out of errors in observables, are discussed.

  9. In-plane resistivity anisotropy in underdoped cuprates due to scattering by charge and spin fluctuations

    NASA Astrophysics Data System (ADS)

    Schütt, Michael; Fernandes, Rafael M.

    2015-03-01

    The existence of strong in-plane electronic anisotropies in underdoped cuprates has been reported by a variety of experimental probes, such as transport measurements, scanning tunneling microscopy, and x-ray and neutron scattering. Understanding the origin of these anisotropies and their interplay is fundamental to elucidate the role played by electronic nematicity in the phase diagram of the cuprates. Here we employ a Boltzmann equation approach to investigate the resistivity anisotropy due to scattering by anisotropic spin and charge fluctuations. We show that while spin fluctuations give rise to larger resistivity along the a direction, charge fluctuations promote larger resistivity along the b direction. Because anisotropic charge and spin fluctuations compete, these behaviors give rise to a particular dependence of the resistivity anisotropy with doping, which is consistent with transport experiments performed in YBa2Cu3O7. We discuss the important role played by the CuO chains in YBCO to select the observed type of nematic domains, and propose transport measurements in strained HgBa2CuO4 and Bi2Sr2CaCu2O8 to shed light on the interplay between anisotropic fluctuations and anisotropic resistivity. MS acknowledges the support from the Humboldt Foundation. RMF is supported by the Department of Energy under Award Number DE-SC0012336.

  10. In-plane Resistivity Anisotropy in Mechanically De- twinned Single Crystals FeSe

    NASA Astrophysics Data System (ADS)

    Timmons, Erik; Tanatar, Makariy; Bohmer, Anna; Drachuck, Gil; Taufour, Valentin; Bud'Ko, Sergey; Canfield, Paul; Prozorov, Ruslan; Schuett, Michael; Fernandes, Rafael; Ruslan Prozorov Group Team; Paul Canfield Group Team; Rafael Fernandes Group Team

    The in-plane resistivity anisotropy was studied in stress-detwinned vapor transport grown single crystals of FeSe, which exhibit the tetragonal-orthorhombic structural transition temperature at Ts ~ 90 K in unstrained samples, but no long-range magnetic order. Direct transport and elastoresistivity measurements show a significant in-plane resistivity anisotropy above Ts induced by a very moderate mechanical stress. This anisotropy peaks slightly below Ts and decreases to nearly zero on cooling to base temperature, while the degree of orthorhombic distortion grows monotonically before saturating at low temperatures. We explain the non-monotonic temperature dependence of the resistivity anisotropy as a result of the inelastic scattering of electrons by anisotropic spin fluctuations. Experimental work was supported by the U.S. DOE/OS/MSED and was performed at the Ames Laboratory, Iowa State University under contract DE-AC02-07CH11358. M.S. acknowledges the support from the Humboldt Foundation. R.M.F. is supported by the U.S. DOE, Office of Science, Basic Energy Sciences, under Award No. DE-SC0012336.

  11. Adaptive Control of Linear Modal Systems Using Residual Mode Filters and a Simple Disturbance Estimator

    NASA Technical Reports Server (NTRS)

    Balas, Mark; Frost, Susan

    2012-01-01

    Flexible structures containing a large number of modes can benefit from adaptive control techniques which are well suited to applications that have unknown modeling parameters and poorly known operating conditions. In this paper, we focus on a direct adaptive control approach that has been extended to handle adaptive rejection of persistent disturbances. We extend our adaptive control theory to accommodate troublesome modal subsystems of a plant that might inhibit the adaptive controller. In some cases the plant does not satisfy the requirements of Almost Strict Positive Realness. Instead, there maybe be a modal subsystem that inhibits this property. This section will present new results for our adaptive control theory. We will modify the adaptive controller with a Residual Mode Filter (RMF) to compensate for the troublesome modal subsystem, or the Q modes. Here we present the theory for adaptive controllers modified by RMFs, with attention to the issue of disturbances propagating through the Q modes. We apply the theoretical results to a flexible structure example to illustrate the behavior with and without the residual mode filter.

  12. Stability against {alpha} decay of some recently observed superheavy elements

    SciTech Connect

    Roy Chowdhury, Partha; Gangopadhyay, G.; Bhattacharyya, Abhijit

    2011-02-15

    The probability of {alpha}-particle emission for some recently observed superheavy nuclei (SHN) are investigated. The {alpha}-decay half-lives of SHN are calculated in a quantum tunneling model with density-dependent M3Y (DDM3Y) effective nuclear interaction using theoretical and measured Q{sub {alpha}} values. We determine the density distribution of {alpha} and daughter nuclei from the relativistic mean-field (RMF) theory using FSUGold force, NL3, and TM1 parameter sets. The double-folded nuclear potential is numerically calculated in a more microscopic manner using these density distributions. The estimated values of {alpha}-decay half-lives are in good agreement with the recent data. We compare our results with recently detected {alpha}-decay chains from a new element with atomic number Z=117 reported by the Joint Institute for Nuclear Research, Dubna. Finally, we determine the half-lives of superheavy elements with Z=108-120 and neutron number N=152-190 to explore the long-standing predictions of the existence of an 'island of stability' due to possible spherical proton (Z{approx}114) and neutron (N{approx}184) shell closures.

  13. Properties of Z = 120 Nuclei and the α-DECAY Chains of the 292, 304120 Isotopes Using Relativistic and Nonrelativistic Formalisms

    NASA Astrophysics Data System (ADS)

    Ahmad, Shakeb; Bhuyan, M.; Patra, S. K.

    2012-11-01

    The ground state and first intrinsic excited state of superheavy nuclei with Z = 120 and N = 160-204 are investigated using both nonrelativistic Skyrme-Hartree-Fock (SHF) and the axially deformed relativistic mean field (RMF) formalisms. We employ a simple BCS pairing approach for calculating the energy contribution from pairing interaction. The results for isotopic chain of binding energy (BE), quadrupole deformation parameter, two neutron separation energies and some other observables are compared with the finite range droplet model (FRDM) and some recent macroscopic-microscopic calculations. We predict superdeformed ground state solutions for almost all the isotopes. Considering the possibility of magic neutron number, two different modes of α-decay chains 292120 and 304120 are also studied within these frameworks. The Qα-values and the half-life T1/2α for these two different modes of decay chains are compared with FRDM and recent macroscopic-microscopic calculations. The calculation is extended for the α-decay chains of 292120 and 304120 from their excited state configuration to respective configuration, which predicts long half-life T1/2α (in seconds).

  14. Hyperon matter at low densities

    SciTech Connect

    Sulaksono, A.

    2014-09-25

    It was reported recently that hyperons can be present inside PSRJ1614-2230 compact star. This can be realized only if the strength of the ω-hyperons and φ-hyperons coupling of conventional hyperons coupling constant on the extended relativistic mean field (ERMF) model increase by a factor of 1.5 to 3. In the present work, the mass and radius relation of the neutron star that is calculated by using BSR28 parameter set of ERMF model augmented with maximal coupling strength of the ω-hyperons and φ-hyperons (X=1), is compared to the mass and radius relation of the neutron star that is predicted by the same RMF parameter set but by assuming that hyperons do not exist in the matter (No. Hyp) as well as those by assuming the hyperons coupling constant fulfilled the conventional SU(6) and SU(3) symmetry. The consequences of implementing X=1 prescription are also discussed. The potential depths of hyperons in symmetric nuclear matter (SNM), pure neutron matter (PNM) and pure lambda matter (PLM) based on this parameter set are also calculated by using the X=1, SU (6) and SU (3) prescriptions. The results are compared to those obtained from microscopic models, quark meson coupling model (χ QMM) and the QCD sum rule for finite density (QCD SM) result.

  15. Nonlinear oscillations of compact stars in the vicinity of the maximum mass configuration

    NASA Astrophysics Data System (ADS)

    Brillante, A.; Mishustin, I. N.

    2015-07-01

    We solve the dynamical GR equations for the spherically symmetric evolution of compact stars in the vicinity of the maximum mass, for which instability sets in according to linear perturbation theory. The calculations are done with the analytical Zeldovich-like EOS P=a≤ft(ρ-ρ_0\\right) and with the TM1 parametrisation of the RMF model. The initial configurations for the dynamical calculations are represented by spherical stars with equilibrium density profile, which are perturbed by either i) an artificially added inward velocity field proportional to the radial coordinate, or ii) a rarefaction corresponding to a static and expanded star. These configurations are evolved using a one-dimensional GR hydro code for ideal and barotropic fluids. Depending on the initial conditions we obtain either stable oscillations or the collapse to a black hole. The minimal amplitude of the perturbation, needed to trigger gravitational collapse is evaluated. The approximate independence of this energy on the type of perturbation is pointed out. At the threshold we find type-I critical behaviour for all stellar models considered and discuss the dependence of the time scaling exponent on the baryon mass and EOS.

  16. Non-invasive quantitative micro-PIXE-RBS/EBS/EBS imaging reveals the lost polychromy and gilding of the Neo-Assyrian ivories from the Louvre collection.

    PubMed

    Albéric, Marie; Müller, Katharina; Pichon, Laurent; Lemasson, Quentin; Moignard, Brice; Pacheco, Claire; Fontan, Elisabeth; Reiche, Ina

    2015-05-01

    Antique objects are known to have been brightly colored. However, the appearance of these objects has changed over time and paint traces are rarely preserved. The surface of ivory objects (8th century B.C., Syria) from the Louvre museum collection (Paris) have been non-invasively studied by simultaneous particle-induced X-ray emission (PIXE) and Rutherford and elastic backscattering spectrometry (RBS/EBS) micro-imaging at the AGLAE facility (C2RMF, Paris). Qualitative 2D chemical images of elements ranging from Na to Pb on the surface of the ancient ivory carvings provide evidence of lost polychromy and gilding. Quantitative PIXE data of specific areas allow discrimination between traces of sediments and former polychromy. Different shades of blue can be differentiated from particular Pb/Cu ratios. The characterization of gilding based on RBS data demonstrates the exceptional technological skills of the Phoenician craftsmen supposed to have carved the Arslan Tash ivories. More precise reconstructions of the original polychromy compared to previous studies and a criterion for the authentication of ancient gilded ivory object are proposed. PMID:25770612

  17. Crates and Transform: Python Interfaces for Data Analysis

    NASA Astrophysics Data System (ADS)

    Lyn, J.; Cresitello-Dittmar, M.; Evans, I.; Evans, J. D.

    2014-05-01

    With its flexible design and ease-of-use, Crates and Transform have been incorporated into the Chandra X-Ray Center's (CXC) data visualization and fitting tools and data processing scripts to facilitate a wide variety of tasks. Chandra's fitting and modeling application, called Sherpa, uses Crates as an underlying data access module, taking advantage of its ability to interpret standard Flexible Image Transport System (FITS) files, such as Redistribution Matrix Files (RMF), Auxiliary Response Files(ARF), and both types of Pulse Height Analysis (PHA) files. The Chandra Imaging and Plotting System (ChIPS) tool utilizes the associated Transform module for visualizing data in different World Coordinate Systems (WCS). By using the CXC DataModel (DM) as a backend, Crates can perform advanced filtering and binning techniques on data. This capability, combined with its simple Application Programming Interface, make it ideal for incorporation into our data analysis scripts, aiding with operations from simple keyword manipulation to creating and writing multiple Header Definition Unit (HDU) files. Crates and Transform are available respectively as the pycrates and pytransform modules within the Chandra Interactive Analysis of Observations (CIAO) environment to assist users with their own analysis threads. In this paper, we will illustrate the capabilities of the Crates and Transform modules and how they are being used within the CXC for analysis.

  18. Interaction of antiprotons with nuclei

    NASA Astrophysics Data System (ADS)

    Hrtánková, Jaroslava; Mareš, Jiří

    2016-01-01

    We performed fully self-consistent calculations of p bar -nuclear bound states using a complex p bar -nucleus potential accounting for p bar -atom data. While the real part of the potential is constructed within the relativistic mean-field (RMF) model, the p bar annihilation in the nuclear medium is described by a phenomenological optical potential. We confirm large polarization effects of the nuclear core caused by the presence of the antiproton. The p bar annihilation is treated dynamically, taking into account explicitly the reduced phase space for annihilation from deeply bound states as well as the compressed nuclear density due to the antiproton. The energy available for the products of p bar annihilation in the nuclear medium is evaluated self-consistently, considering the additional energy shift due to transformation from the p bar N system to p bar -nucleus system. Corresponding p bar widths in the medium are significantly suppressed, however, they still remain considerable for the p bar potential consistent with experimental data.

  19. CHIRAL MODEL FOR DENSE, HOT AND STRANGE HADRONIC MATTER

    SciTech Connect

    ZSCHIESCHE,D.; PAPAZOGLOU,P.; BECKMANN,C.W.; SCHRAMM,S.; SCHAFFNER-BIELICH,J.; STOCKER,H.; GREINER,W.

    1999-06-10

    Until now it is not possible to determine the equation of state (EOS) of hadronic matter from QCD. One successfully applied alternative way to describe the hadronic world at high densities and temperatures are effective models like the RMF-models, where the relevant degrees of freedom are baryons and mesons instead of quarks and gluons. Since approximate chiral symmetry is an essential feature of QCD, it should be a useful concept for building and restricting effective models. It has been shown that effective {sigma}-{omega}-models including SU(2) chiral symmetry are able to obtain a reasonable description of nuclear matter and finite nuclei. Recently [4] the authors have shown that an extended SU(3) x SU(3) chiral {sigma}-{omega} model is able to describe nuclear matter ground state properties, vacuum properties and finite nuclei satisfactorily. This model includes the lowest SU(3) multiplets of the baryons (octet and decuplet), the spin-0 and the spin-1 mesons as the relevant degrees of freedom. Here they discuss the predictions of this model for dense, hot, and strange hadronic matter.

  20. Non-destructive provenance differentiation of prehistoric pigments by external PIXE

    NASA Astrophysics Data System (ADS)

    Beck, L.; Salomon, H.; Lahlil, S.; Lebon, M.; Odin, G. P.; Coquinot, Y.; Pichon, L.

    2012-02-01

    The elemental analysis of minerals/rocks has been often used for the determination of their geological origin. When these natural rocks were exploited by prehistoric civilizations as objects, weapons, or pigments, the composition of the minerals can provide information on the mobility, the exchanges and the interaction between groups of population. In this paper, we will present results obtained from archaeological samples of prehistoric pigments, mainly iron and manganese oxides. PIXE analysis has been applied to samples of the prehistoric cave "La grotte du Renne" in Arcy-sur-Cure, France (Chatelperronian, 38,000-34,000 BP). Because most of the archaeological objects are decorated or display some use marks, it is not possible to take samples. Consequently, we have used a non-destructive technique thanks to the external beam of AGLAE (C2RMF, Paris). In order to improve the limits of detection (LOD less than 10 ppm from Cu to Sb), a metal absorber has been placed on the X-ray detector to preferentially filter the Fe-K or Mn-K lines. Based on the quantitative analysis of major and trace elements, we have obtained groups of compositions corresponding to different geological sources. We demonstrate in this study that it is possible to extend PIXE analysis to the characterization of prehistoric pigments such as iron and manganese oxides for differentiating potential sources of pigments in archaeological contexts.

  1. [Not Available].

    PubMed

    Martínez de Victoria, Emilio

    2016-01-01

    El calcio (Ca) es el elemento mineral más abundante en nuestro organismo, ya que forma parte importante del esqueleto y los dientes. Supone alrededor del 2% del peso corporal. Las funciones del calcio son: a) funciones esqueléticas y b) funciones reguladoras. El hueso está formado por una matriz proteica que se mineraliza de forma mayoritaria con calcio (el más abundante), fosfato y magnesio; para ello es imprescindible un correcto aporte dietético de Ca, fósforo y vitamina D. El Ca iónico (Ca2+) es un componente celular imprescindible para mantener y/o realizar las diferentes funciones especializadas de prácticamente todas las células del organismo. Debido a sus importantes funciones, el Ca2+ debe estar estrechamente regulado, manteniéndose sus concentraciones plasmáticas dentro de unos rangos estrechos. Para ello existe una respuesta precisa frente a la hipocalcemia o la hipercalcemia, en la que intervienen la parathormona, el calcitriol, la calcitonina y la vitamina K. Las ingestas de Ca en la población española son bajas en un porcentaje significativo de la población, especialmente en adultos mayores, sobre todo en las mujeres. La principal fuente de Ca en la dieta son la leche y todos sus derivados. Las verduras de hoja verde, frutas y legumbres pueden tener importancia como fuentes de Ca en un patrón alimentario mediterráneo. La biodisponibilidad del Ca de la dieta depende de factores fisiológicos y dietéticos. Los fisiológicos incluyen la edad, situación fisiológica (gestación y lactación), el estatus de Ca y vitamina D y la enfermedad. Diversos estudios relacionan la ingesta de Ca en la dieta y distintas enfermedades, como osteoporosis, cáncer, enfermedades cardiovasculares y obesidad. PMID:27571860

  2. Nanoparticulas basadas en complejos de Fe(II) con transicion de espin: sintesis, caracterizacion y aplicaciones en electronica molecular

    NASA Astrophysics Data System (ADS)

    Monrabal Capilla, Maria

    Esta tesis doctoral esta organizada en 5 capitulos y esta destinada al estudio de sistemas de Fe (II) que presentan el fenomeno de la transicion de espin a escala nanometrica. El capitulo 1 contiene una introduccion general sobre materiales moleculares multifuncionales, destacando aquellos ejemplos mas importantes. Por otro lado, se explicara el fenomeno de la transicion de espin, tratando aspectos conceptuales, los antecedentes mas importantes y la situacion actual. En el capitulo 2 se describen los diferentes procesos existentes para la obtencion de diferentes tipos de nanoparticulas. Ademas, se presenta la sintesis y caracterizacion de nanoparticulas del polimero de coordinacion unidimensional [Fe(Htrz)2(trz)]BF4, obtenidas mediante el metodo de micelas inversas. Estas nanoparticulas, con una estrecha distribucion de tamanos centrada alrededor de los 11 nm, presentan una transicion de espin muy abrupta, con un ancho ciclo de histeresis termica de unos 40K. En el capitulo 3 se describe el proceso de modificacion del tamano de las nanoparticulas descritas en el capitulo anterior, llevado a cabo variando la proporcion de surfactante/H2O en el medio. Ademas, con el objetivo de modificar las propiedades magneticas de las nanoparticulas obtenidas en el capitulo 2, se lleva a cabo la sintesis de nanoparticulas de polimeros de la misma familia del [Fe(Htrz)2(trz)]BF4. En concreto se sintetizaron 3 nuevos tipos de nanoparticulas basadas en el polimero [Fe(Htrz)1-x(NH2trz)x](ClO4)2, siendo x = 0.05, 0.15 y 0.3, en cada caso. Estas nanoparticulas siguen presentando una estrecha distribucion de tamanos y una transicion de espin muy abrupta y con un ancho ciclo de histeresis. Ademas, se observa que este ciclo se desplaza a temperaturas mas proximas a la temperatura ambiente a medida que se aumenta el porcentaje de 4-amino-1, 2, 4- triazol en la muestra. Pero al mismo tiempo se produce una disminucion de la anchura de este ciclo. Por ultimo, en este capitulo se presenta la

  3. Introduzione Nuove tecnologie in urologia.

    PubMed

    Bianchi, Giampaolo

    2011-03-30

    emergenti (LESS e NOTES), poco è riportato in letteratura. Altri robot esistono nel mondo urologico che si stanno sviluppando e miniaturizzando (nanotecnologia), questi avranno una maggiore indipendenza nell'esecuzione di alcune manovre chirurgiche. Chirurgia computer assistita Il primo realizzato è stato PAKY, da allora il laboratorio di "urobotica", diretto dall'Ing. Dan Stoianovici, ha sviluppato nuovi prototipi di robot controllati mediante TAC o risonanza magnetica. Con questa tecnologia si programma l'intervento sulla base dell'"imaging" preoperatorio ed il robot esegue autonomamente biopsie ed altri interventi. Oggi sono molti i laboratori di ingegneria-urologica che lavorano nella realizzazione di altri robot (Probot, Acubot, Mr-Bot, Pneu-Step) dedicati all'Image-Guided System (IGS). Realtà virtuale Avanzati sistemi di computer grafica affiancati alle nuove ricostruzioni tridimensionali di TAC e RM, riescono a creare filmati dell'anatomia interna dei pazienti, in particolare degli organi cavi. Con la realtà virtuale si possono assistere tutte le manovre endoscopiche, migliorando notevolmente l'accuratezza della diagnosi delle patologie urologiche. A questo punto il passaggio al "Tissue Navigation System" è automatico, usato da alcuni anni con successo da neurochirurghi e cardiochirurghi. Alcuni recenti studi vengono dalla Cleveland Clinic Fondation (I. Gill), che lo utilizza per assistere interventi di laparoscopia ed endoscopia urologica. I risultati sono entusiasmanti: precisione millimetrica nel rispetto dei margini oncologici, delle strutture neuro-vascolari e linfonodali. Questi sistemi di navigazione abbattono la lunga "learning curve" delle metodiche endoscopiche, riducendo il tempo operatorio ed il rischio di complicanze chirurgiche. PMID:21452158

  4. A Possible Origin of the H-H Objects in Young Stellar Outflows

    NASA Astrophysics Data System (ADS)

    de Gouveia dal Pino, E.; Opher, R.

    1990-11-01

    RESUMEN. La presencIa de flujos coljmados asocjados con objetos estelares j6venes es un fen6meno comun en reglones de formacI6n estelar. Estos chorros frecuentemente muestran una cadena de reglones de lineas de emjsI6n, a varIas de las cuales se les conoce desde bace mucho tlempo objetos HerbIg-Haro (HAl). En el presente trabajo examjnamos la poslbIlI dad de que estos nudos sean condensaciones producIdas por inestabilidad termica en un plasma que se se expande sujeto a `bremsstrahlung' reco - binaci6n y perdida por radjacj5n en lineas de emjsj6n. Nostramos que el valor minimo de = P0/PN0 bajo condjcjones Isobaricas para el crecimien to de la inestabilidad termica es = (6/5) [9/(STc\\)e) - 3/2]; en donde P0 es la presi6n de particulas, PM0 la presi6n magnetica, `)e la tasa de expansI5n y Tc el tiempo de enfriatniento radiativo en el flujo (3eI plasma ambiente. Haciendo calculos no lineales, encontratnos que l9s flujos colitnados de temperatura K, tasas de perdida de masa `4 = 10-6 - lO 8 Ne y velocidades de flujo VJ = 100-400 km/s, resultan favorables para la formacl6n de condensaciones por inestabilidad termica con contrastes de densidad Pp/ .3 -2.0 creados en intervalos de tiempo mas cortos que el tiempo estirnado de expansl6n en los chorros, en donde Pp(Po) es la densidad en la regi5n (ambiente) perturbada. ABSTRACT. The presence of collimated outflows associated with young stellar objects is a common phenomenon in star-fortning regions. These jets frequently show a chain of emission-line regions several of which have long been known as Herbig-Haro (H-H) objects. In this paper we examine the possibility that these knots are condensations produced by thermal instability in an expanding plasma , recombination and emission-line radiation losses. We show that the minimum value of = P /PNo under isobaric conditions for the growth of a thermal instability 0is = (6/5)1 [9/(STcN)e) - 3/2]; where P0 is the particle pressure, NQ tWe magnetic pressure, N) the expansion rate

  5. TESTING OF THE DUAL ROTARY FILTER SYSTEM

    SciTech Connect

    Herman, D.; Fowley, M.; Stefanko, D.

    2011-08-29

    The Savannah River National Laboratory (SRNL) installed and tested two hydraulically connected SpinTek rotary microfilter (RMF) units to determine the behavior of a multiple filter system. Both units were successfully controlled by a control scheme written in DELTA-V architecture by Savannah River Remediation (SRR) Process Control Engineering personnel. The control system was tuned to provide satisfactory response to changing conditions during the operation of the multi-filter system. Stability was maintained through the startup and shutdown of one of the filter units while the second was still in operation. The installation configuration originally proposed by the Small Colum Ion Exchange (SCIX) project of independent filter and motor mountings may be susceptible to vibration. Significant stiffening of the filter and motor mounts was required to minimize the vibration. Alignment of the motor to the filter was a challenge in this test configuration. The deployment configuration must be easy to manipulate and allow for fine adjustment. An analysis of the vibration signature of the test system identified critical speeds. Whether it corresponds to the resonance frequency of a rotor radial vibration mode that was excited by rotor unbalance is uncertain based upon the measurements. A relative motion series should be completed on the filter with the final shaft configuration to determine if the resonances exist in the final filter design. The instrumentation selected for deployment, including the concentrate discharge control valve and flow meters, performed well. Automation of the valve control integrated well with the control scheme and when used in concert with the other control variables, allowed automated control of the dual RMF system. The one area of concern with the instrumentation was the condition resulting when the filtrate flow meter operated with less than three gpm. This low flow was at the lower range of performance for the flow meter. This should not be

  6. Dirac-Hartree-Bogoliubov calculation for spherical and deformed hot nuclei: Temperature dependence of the pairing energy and gaps, nuclear deformation, nuclear radii, excitation energy, and entropy

    NASA Astrophysics Data System (ADS)

    Lisboa, R.; Malheiro, M.; Carlson, B. V.

    2016-02-01

    Background: Unbound single-particle states become important in determining the properties of a hot nucleus as its temperature increases. We present relativistic mean field (RMF) for hot nuclei considering not only the self-consistent temperature and density dependence of the self-consistent relativistic mean fields but also the vapor phase that takes into account the unbound nucleon states. Purpose: The temperature dependence of the pairing gaps, nuclear deformation, radii, binding energies, entropy, and caloric curves of spherical and deformed nuclei are obtained in self-consistent RMF calculations up to the limit of existence of the nucleus. Method: We perform Dirac-Hartree-Bogoliubov (DHB) calculations for hot nuclei using a zero-range approximation to the relativistic pairing interaction to calculate proton-proton and neutron-neutron pairing energies and gaps. A vapor subtraction procedure is used to account for unbound states and to remove long range Coulomb repulsion between the hot nucleus and the gas as well as the contribution of the external nucleon gas. Results: We show that p -p and n -n pairing gaps in the S10 channel vanish for low critical temperatures in the range Tcp≈0.6 -1.1 MeV for spherical nuclei such as 90Zr, 124Sn, and 140Ce and for both deformed nuclei 150Sm and 168Er. We found that superconducting phase transition occurs at Tcp=1.03 Δp p(0 ) for 90Zr, Tcp=1.16 Δp p(0 ) for 140Ce, Tcp=0.92 Δp p(0 ) for 150Sm, and Tcp=0.97 Δp p(0 ) for 168Er. The superfluidity phase transition occurs at Tcp=0.72 Δn n(0 ) for 124Sn, Tcp=1.22 Δn n(0 ) for 150Sm, and Tcp=1.13 Δn n(0 ) for 168Er. Thus, the nuclear superfluidity phase—at least for this channel—can only survive at very low nuclear temperatures and this phase transition (when the neutron gap vanishes) always occurs before the superconducting one, where the proton gap is zero. For deformed nuclei the nuclear deformation disappear at temperatures of about Tcs=2.0 -4.0 MeV , well above the

  7. Information display and interaction in real-time environments

    NASA Technical Reports Server (NTRS)

    Bocast, A. K.

    1983-01-01

    The available information bandwidth as a funcion of system's complexity and time constraints in a real time control environment were examined. Modern interactive graphics techniques provide very high bandwidth data displays. In real time control environments, effective information interaction rates are a function not only of machine data technologies but of human information processing capabilities and the four dimensional resolution of available interaction techniques. The available information bandwidth as a function of system's complexity and time constraints in a real time control environment were examined.

  8. DESIGN OF A MOLECULAR BEAM SURFACE SCATTERING APPARATUS FOR VELOCITY AND ANGULAR DISTRIBUTION MEASUREMENTS

    SciTech Connect

    Ceyer, S. T.; Siekhaus, W. J.; Somorjai, G. A.

    1980-11-01

    A molecular beam surface scattering apparatus designed for the study of corrosion and catalyticsurfacereactions is described. The apparatus incorporates two molecular or atomic beams aimed at a surface characterized by low energy electron diffraction (LEED) and Auger electron spectroscopy (AES), a rotatable, differentially pumped quadrupole mass spectrometer, and a versatile manipulator. Angular distributions and energy distributions as a funcion of angle and independent of the surface residence time can be measured. Typical data for the oxidation of deuterium to D{sub 2}O on a Pt(lll) crystal surface are presented.

  9. Unusual Application Of Ion Beam Analysis For The Study Of Surface Layers On Materials Relevant To Cultural Heritage

    NASA Astrophysics Data System (ADS)

    Mathis, F.; Salomon, J.; Trocellier, P.; Aucouturier, M.

    2006-12-01

    Recently a new thematic of research — intentional patinas on antic copper-base objects — lead the AGLAE (Accélérateur Grand Louvre pour l'Analyse Elémentaire) team of the C2RMF (Centre de Recherche et de Restauration des Musées de France) to improve its methods of analyzing thin surface layers both in their elemental composition and in-depth elemental distribution. A new beam extraction set-up containing a particle detector has been developed in order to use a 6 MeV alpha beam both in PIXE and RBS mode and to monitor precisely the ion dose received by the sample. Both RBS and ionization cross sections were assessed in order to make sure that the analysis can be quantitative. This set up allows great progresses in the understanding of both nature and structure of this very particular oxide layer obtained in the antiquity by chemical treatment on copper alloys, containing gold and/or silver and presenting very interesting properties of color and stability. Besides the non destructive properties of the IBA in external beam mode, this method of analyzing allows the study of samples in interaction with its environment. This was used to study the high temperature oxidation of Cu-Sn alloys using a furnace developed in order to heat a sample and analyze it in RBS mode at the same time. This new way of studying the growth of oxide layers permits to understand the oxidation mechanism of this system and to propose an experimental model for the identification of oxide layers due to an exposition to a high temperature, model needed for a long time by curators in charge of the study and the conservation of archaeological bronzes.

  10. The Listeria monocytogenes hibernation-promoting factor is required for the formation of 100S ribosomes, optimal fitness, and pathogenesis.

    PubMed

    Kline, Benjamin C; McKay, Susannah L; Tang, William W; Portnoy, Daniel A

    2015-02-01

    During exposure to certain stresses, bacteria dimerize pairs of 70S ribosomes into translationally silent 100S particles in a process called ribosome hibernation. Although the biological roles of ribosome hibernation are not completely understood, this process appears to represent a conserved and adaptive response that contributes to optimal survival during stress and post-exponential-phase growth. Hibernating ribosomes are formed by the activity of one or more highly conserved proteins; gammaproteobacteria produce two relevant proteins, ribosome modulation factor (RMF) and hibernation promoting factor (HPF), while most Gram-positive bacteria produce a single, longer HPF protein. Here, we report the formation of 100S ribosomes by an HPF homolog in Listeria monocytogenes. L. monocytogenes 100S ribosomes were observed by sucrose density gradient centrifugation of bacterial extracts during mid-logarithmic phase, peaked at the transition to stationary phase, and persisted at lower levels during post-exponential-phase growth. 100S ribosomes were undetectable in bacteria carrying an hpf::Himar1 transposon insertion, indicating that HPF is required for ribosome hibernation in L. monocytogenes. Additionally, epitope-tagged HPF cosedimented with 100S ribosomes, supporting its previously described direct role in 100S formation. We examined hpf mRNA by quantitative PCR (qPCR) and identified several conditions that upregulated its expression, including carbon starvation, heat shock, and exposure to high concentrations of salt or ethanol. Survival of HPF-deficient bacteria was impaired under certain conditions both in vitro and during animal infection, providing evidence for the biological relevance of 100S ribosome formation. PMID:25422304

  11. A new light on a first example of lustred majolica in Italy

    NASA Astrophysics Data System (ADS)

    Padeletti, G.; Fermo, P.; Bouquillon, A.; Aucouturier, M.; Barbe, F.

    2010-09-01

    A study has been realised to elucidate the first step of lustre production in Italy. With this aim in mind, an investigation was carried out on an emblematic lustred object: Baglioni’s albarello. It is conserved at Louvre museum and it is considered as one of the very first examples of lustred object produced in Italy. The characteristics of the lustred film have been determined, identifying interesting aspects that may be used to scientifically confirm the origin of this object. This study was completed by the investigation of other objects: a not lustred albarello, still decorated with the coat of arms of Baglioni’s family and a lustred plate with the coat of arms of the Montefeltro family. The two Baglioni’s albarelli are stylistically and historically considered as produced in one of the numerous workshops of Deruta. The origin of the Montefeltro’s plate, although from central Italy, is not precisely attested. In order to acquire more information, clarifying the origin and place of production of these objects, a comparison of their physico-chemical characteristics with results obtained and already published on different well-attested productions, such as Islamic, Hispano-Moresque and Italian, was carried out. For what concerns the museum objects, the use of non-destructive investigation techniques was mandatory. For this reason, ion beam techniques as PIXE and RBS have been used at AGLAE facility, as well as a new X-ray micro-diffraction equipment, at C2RMF. Moreover, the results were compared with data obtained on shards of certain production origin, by means of chemometric techniques. Some hypothesis concerning the place of production of the examined objects have been formulated.

  12. TH-A-19A-05: Modeling Physics Properties and Biologic Effects Induced by Proton and Helium Ions

    SciTech Connect

    Taleei, R; Titt, U; Peeler, C; Guan, F; Mirkovic, D; Grosshans, D; Mohan, R

    2014-06-15

    Purpose: Currently, proton and carbon ions are used for cancer treatment. More recently, other light ions including helium ions have shown interesting physical and biological properties. The purpose of this work is to study the biological and physical properties of helium ions (He-3) in comparison to protons. Methods: Monte Carlo simulations with FLUKA, GEANT4 and MCNPX were used to calculate proton and He-3 dose distributions in water phantoms. The energy spectra of proton and He-3 beams were calculated with high resolution for use in biological models. The repair-misrepairfixation (RMF) model was subsequently used to calculate the RBE. Results: The proton Bragg curve calculations show good agreement between the three general purpose Monte Carlo codes. In contrast, the He-3 Bragg curve calculations show disagreement (for the magnitude of the Bragg peak) between FLUKA and the other two Monte Carlo codes. The differences in the magnitude of the Bragg peak are mainly due to the discrepancy in the secondary fragmentation cross sections used by the codes. The RBE for V79 cell lines is about 0.96 and 0.98 at the entrance of proton and He-3 ions depth dose respectively. The RBE increases to 1.06 and 1.59 at the Bragg peak of proton and He-3 ions. The results demonstrated that LET, microdosimetric parameters (such as dose-mean lineal energy) and RBE are nearly constant along the plateau region of Bragg curve, while all parameters increase within the Bragg peak and at the distal edge for both proton and He-3 ions. Conclusion: The Monte Carlo codes should revise the fragmentation cross sections to more accurately simulate the physical properties of He-3 ions. The increase in RBE for He-3 ions is higher than for proton beams at the Bragg peak.

  13. Eleven-year descriptive analysis of closed court verdicts on medical errors in Spain and Massachusetts

    PubMed Central

    Giraldo, Priscila; Sato, Luke; Martínez-Sánchez, Jose M; Comas, Mercè; Dwyer, Kathy; Sala, Maria; Castells, Xavier

    2016-01-01

    Objectives To evaluate and compare the characteristics of court verdicts on medical errors allegedly harming patients in Spain and Massachusetts from 2002 to 2012. Design, setting and participants We reviewed 1041 closed court verdicts obtained from data on litigation in the Thomson Reuters Aranzadi Westlaw databases in Spain (Europe), and 370 closed court verdicts obtained from the Controlled Risk and Risk Management Foundation of Harvard Medical Institutions (CRICO/RMF) in Massachusetts (USA). We included closed court verdicts on medical errors. The definition of medical errors was based on that of the Institute of Medicine (USA). We excluded any agreements between parties before a judgement. Results Medical errors were involved in 25.9% of court verdicts in Spain and in 74% of those in Massachusetts. The most frequent cause of medical errors was a diagnosis-related problem (25.1%; 95% CI 20.7% to 31.1% in Spain; 35%; 95% CI 29.4% to 40.7% in Massachusetts). The proportion of medical errors classified as high severity was 34% higher in Spain than in Massachusetts (p=0.001). The most frequent factors contributing to medical errors in Spain were surgical and medical treatment (p=0.001). In Spain, 98.5% of medical errors resulted in compensation awards compared with only 6.9% in Massachusetts. Conclusions This study reveals wide differences in litigation rates and the award of indemnity payments in Spain and Massachusetts; however, common features of both locations are the high rates of diagnosis-related problems and the long time interval until resolution. PMID:27577585

  14. Microscopic Self-consistent Study of Neon Halos with Resonant Contributions

    SciTech Connect

    Zhang, Shisheng; Smith, Michael Scott; Kang, Zhong-Shu; Zhao, Jie

    2014-01-01

    Recent reaction measurements have been interpreted as evidence of a halo structure in the exotic neutron-rich isotopes 29,31Ne. While theoretical studies of 31Ne generally agree on its halo nature, they differ significantly in their predictions of its properties and underlying cause (e.g., that 31Ne lies in an "island of inversion'"). We have made a systematic theoretical analysis of possible Neon halo signatures -- the first using a fully microscopic, relativistic mean field approach that properly treats positive energy orbitals (such as the valence neutron in 31Ne) self-consistently with bound levels, and that includes the pairing effect that keeps the nucleus loosely bound with negative Fermi energy. Our model is the analytical continuation of the coupling constant (ACCC) method based on a relativistic mean field (RMF) theory with Bardeen-Cooper-Schrieffer (BCS) pairing approximation. We calculate neutron- and matter-radii, one-neutron separation energies, p- and f-orbital energies and occupation probabilities, and neutron densities for single-particle resonant orbitals in 27-31Ne. We analyze these results for evidence of neutron halo formation in 29,31Ne. Our model predicts a p-orbit 1n halo structure for 31Ne, based on a radius increase from 30Ne that is 7 - 8 times larger than the increase from 29Ne to 30Ne, as well as a decrease in the neutron separation energy by a factor of ~ 10 compared to that of 27-30Ne. In contrast to other studies, our inclusion of resonances yields an inverted ordering of p and f orbitals for small deformations. Furthermore, we find no evidence of an s-orbit 1n halo in 29Ne as recently claimed in the literature.

  15. PIXE analysis of historical paintings: Is the gain worth the risk?

    NASA Astrophysics Data System (ADS)

    Calligaro, T.; Gonzalez, V.; Pichon, L.

    2015-11-01

    The PIXE analysis of easel paintings constitutes a challenging task. Despite recognized merits and a few emblematic applications, PIXE has never been routinely applied to these fragile, complex and precious targets. The present work discusses the place of PIXE in the study of easel paintings and opens up perspectives for a more systematic usage of this analytical technique. Progress achieved since decades in the implementation of PIXE to study such fragile cultural heritage artefacts is reviewed, notably at the LABEC laboratory in Italy and at the AGLAE facility of the C2RMF in France. Two specific techniques developed for paintings are detailed and exemplified on Renaissance painting masterpieces: differential PIXE for paint layers depth profiling and multi-scale elemental mapping for the imaging of pigment distribution. Beam-induced damage, a major concern, notably depends on the employed beam fluence in particle/cm2 or μC/cm2. After recalling previous works on damage induced in chemical products comparable to pigments, we present the behaviour under different fluences of protons of a few MeV (1-300 μC/cm2) of targets having high resemblance to historical easel paintings: pellets of specially synthesized lead white pigments, layers of lead white mixed with linseed oil and areas containing lead white of two 19th century paintworks. The results shed new lights on the behaviour of paintworks under the beam and pave the way to strategies for damage mitigation. In particular, the lowering of PIXE performance induced by the decrease of the beam fluence sets a trade-off between risk of damage and gained information which also impacts the PIXE scanning protocol for paintings. As an illustration of an adequate adjustment of this balance, we report the exploratory application of PIXE mapping to a large area of a 19th century easel painting without damage. The recorded elemental maps are compared to elemental maps collected on the same area using laboratory-based scanning

  16. Microscopic self-consistent study of neon halos with resonant contributions

    NASA Astrophysics Data System (ADS)

    Zhang, Shi-Sheng; Smith, Michael S.; Kang, Zhong-Shu; Zhao, Jie

    2014-03-01

    Recent reaction measurements have been interpreted as evidence of a halo structure in the exotic neutron-rich isotopes 29,31Ne. While theoretical studies of 31Ne generally agree on its halo nature, they differ significantly in their predictions of its properties and underlying cause (e.g., that 31Ne has an inverted ordering of p-f orbitals). We have made a systematic theoretical analysis of possible Neon halo signatures - the first using a fully microscopic, relativistic mean field approach that properly treats positive energy orbitals (such as the valence neutron in 31Ne) self-consistently with bound levels, as well as the pairing effect that keeps the nucleus loosely bound with negative Fermi energy. Our model is the analytical continuation of the coupling constant (ACCC) method based on a relativistic mean field (RMF) theory with Bardeen-Cooper-Schrieffer (BCS) pairing approximation. We calculate neutron- and matter-radii, one-neutron separation energies, p- and f-orbital energies and occupation probabilities, and neutron densities for single-particle resonant orbitals in 27-31Ne. We analyze these results for evidence of neutron halo formation in 29,31Ne. Our model predicts a p-orbit 1n halo structure for 31Ne, based on a radius increase from 30Ne that is 7-8 times larger than the increase from 29Ne to 30Ne, as well as a decrease in the neutron separation energy by a factor of ∼10 compared to that of 27-30Ne. In contrast to some other studies, our inclusion of resonances yields an inverted ordering of p and f orbitals for spherical and slightly deformed nuclei. Furthermore, we find no evidence of an s-orbit 1n halo in 29Ne as recently claimed in the literature.

  17. SU-E-T-547: Modeling Biological Response to Proton Irradiation and Evaluating Its Potential Clinical Consequences

    SciTech Connect

    Taleei, R; Peeler, C; Guan, F; Patel, D; Titt, U; Mirkovic, D; Grosshans, D; Mohan, R

    2015-06-15

    Purpose: In addition to physical uncertainties, proton therapy may also be associated with biologic uncertainties. Currently a generic RBE value of 1.1 is used for treatment planning. In this work the effects of variable RBE, in comparison to a fixed RBE, were evaluated by calculating the effective dose for proton treatments. Methods: The repair misrepair fixation (RMF) model was used to calculate variable proton RBEs. The RBE weighted spread-out Bragg peak (SOBP) dose in water phantom was calculated using Monte Carlo simulation and compared to 1.1 weighted SOBP dose. A head and neck proton treatment was used to evaluate the potential effects, by comparing the head and neck treatment plan computed with a commercial treatment planning system that incorporates fixed RBE of 1.1 and a Monte Carlo treatment planning system that incorporates variable RBE. Results: RBE calculations along the depth of SOBP showed that the RBE at the entrance is approximately 1 and reaches 1.1 near the center of the SOBP. However, in distal regions the RBE rises to higher values (up to 3.5 depending on the cell type). Comparison of commercial treatment plans using a fixed RBE of 1.1 and Monte Carlo using variable RBE showed noticeable differences in the effective dose distributions. Conclusion: The comparison of the treatment planning with fixed and variable RBE shows that using commercial treatment planning systems that incorporate fixed RBE (1.1) could Result in overestimation of the effective dose to part of head and neck target volumes, while underestimating the effective dose to the normal tissue beyond the tumor. The accurate variable RBE as a function of proton beam energy in patient should be incorporated in treatment planning to improve the accuracy of effective dose calculation.

  18. Cold Uniform Matter and Neutron Stars in the Quark-Meson-Coupling Model

    SciTech Connect

    J.R. Stone; P.A.M. Guichon; H.H. Matevosyan; A.W. Thomas

    2007-08-01

    A new density dependent effective baryon-baryon interaction has been recently derived from the quark-meson-coupling (QMC) model, offering impressive results in application to finite nuclei and dense baryon matter. This self-consistent, relativistic quark-level approach is used to construct the Equation of State (EoS) and to calculate key properties of high density matter and cold, slowly rotating neutron stars. The results include predictions for the maximum mass of neutron star models, together with the corresponding radius and central density, as well the properties of neutron stars with mass of order 1.4 M{sub {circle_dot}}. The cooling mechanism allowed by the QMC EoS is explored and the parameters relevant to slow rotation, namely the moment of inertia and the period of rotation investigated. The results of the calculation, which are found to be in good agreement with available observational data, are compared with the predictions of more traditional EoS, based on the A18+{delta}v+UIX* and modified Reid soft core potentials, the Skyrme SkM* interaction and two relativistic mean field (RMF) models for a hybrid stars including quark matter. The QMC EoS provides cold neutron star models with maximum mass 1.9-2.1 M{sub {circle_dot}}, with central density less than 6 times nuclear saturation density (n{sub 0} = 0.16 fm{sup -3}) and offers a consistent description of the stellar mass up to this density limit. In contrast with other models, QMC predicts no hyperon contribution at densities lower than 3n{sub 0}, for matter in {beta}-equilibrium. At higher densities, {Xi}{sup -,0} and {Lambda} hyperons are present. The absence of lighter {Sigma}{sup {+-},0} hyperons is understood as a consequence of antisymmetrization, together with the implementation of the color hyperfine interaction in the response of the quark bag to the nuclear scalar field.

  19. Unusual Application Of Ion Beam Analysis For The Study Of Surface Layers On Materials Relevant To Cultural Heritage

    SciTech Connect

    Mathis, F.; Salomon, J.; Aucouturier, M.; Trocellier, P.

    2006-12-01

    Recently a new thematic of research -- intentional patinas on antic copper-base objects -- lead the AGLAE (Accelerateur Grand Louvre pour l'Analyse Elementaire) team of the C2RMF (Centre de Recherche et de Restauration des Musees de France) to improve its methods of analyzing thin surface layers both in their elemental composition and in-depth elemental distribution. A new beam extraction set-up containing a particle detector has been developed in order to use a 6 MeV alpha beam both in PIXE and RBS mode and to monitor precisely the ion dose received by the sample. Both RBS and ionization cross sections were assessed in order to make sure that the analysis can be quantitative. This set up allows great progresses in the understanding of both nature and structure of this very particular oxide layer obtained in the antiquity by chemical treatment on copper alloys, containing gold and/or silver and presenting very interesting properties of color and stability.Besides the non destructive properties of the IBA in external beam mode, this method of analyzing allows the study of samples in interaction with its environment. This was used to study the high temperature oxidation of Cu-Sn alloys using a furnace developed in order to heat a sample and analyze it in RBS mode at the same time. This new way of studying the growth of oxide layers permits to understand the oxidation mechanism of this system and to propose an experimental model for the identification of oxide layers due to an exposition to a high temperature, model needed for a long time by curators in charge of the study and the conservation of archaeological bronzes.

  20. Multidimensionally-constrained relativistic mean-field study of spontaneous fission: Coupling between shape and pairing degrees of freedom

    NASA Astrophysics Data System (ADS)

    Zhao, Jie; Lu, Bing-Nan; Nikšić, Tamara; Vretenar, Dario; Zhou, Shan-Gui

    2016-04-01

    Background: Studies of fission dynamics, based on nuclear energy density functionals, have shown that the coupling between shape and pairing degrees of freedom has a pronounced effect on the nonperturbative collective inertia and, therefore, on dynamic (least-action) spontaneous fission paths and half-lives. Purpose: The aim is to analyze the effects of particle-number fluctuation degrees of freedom on symmetric and asymmetric spontaneous fission (SF) dynamics, and to compare the findings with the results of recent studies based on the self-consistent Hartree-Fock-Bogoliubov (HFB) method. Methods: Collective potentials and nonperturbative cranking collective inertia tensors are calculated using the multidimensionally-constrained relativistic-mean-field (MDC-RMF) model. Pairing correlations are treated in the BCS approximation using a separable pairing force of finite range. Pairing fluctuations are included as a collective variable using a constraint on particle-number dispersion. Fission paths are determined with the dynamic programming method by minimizing the action in multidimensional collective spaces. Results: The dynamics of spontaneous fission of 264Fm and 250Fm are explored. Fission paths, action integrals, and corresponding half-lives computed in the three-dimensional collective space of shape and pairing coordinates, using the relativistic functional DD-PC1 and a separable pairing force of finite range, are compared with results obtained without pairing fluctuations. Results for 264Fm are also discussed in relation with those recently obtained using the HFB model. Conclusions: The inclusion of pairing correlations in the space of collective coordinates favors axially symmetric shapes along the dynamic path of the fissioning system, amplifies pairing as the path traverses the fission barriers, significantly reduces the action integral, and shortens the

  1. Interactions effectives, théories de champ moyen masses et rayons nucléaires

    NASA Astrophysics Data System (ADS)

    Meyer, J.

    2003-05-01

    Effective interactions, mean field theories, masses and nuclear radii A review of effective interactions used in mean field theories for the description of properties of atomic nuclei is presented. Relativistic as well as non relativistic theories are discussed with a special attention to the cases where their results are very different. We will concentrate on the effective forces built up to investigate the nuclear medium in extreme conditions. Masses and r.m.s. radii along long chain of isotopes will be discussed. Large deformations, as observed in the fission of heavy nuclei, and exotic neutron rich nuclei will be taken as examples of these extreme conditions. Le principal propos de cet ouvrage est : (i) de passer en revue les outils théoriques utilisés sous le sigle ”théories microscopiques de champ moyen ”. Sans entrer dans le détail des formalismes (le lecteur sera systématiquement renvoyé ”pour en savoir plus ” à des cours plus complets qui ont déjà été donnés dans le passé à l'École Joliot-Curie) il s'agira surtout de préciser le contexte, les hypothèses et les approximations qui se cachent sous les sigles : Hartree-Fock (HF), Hartree-Fock-Bogoliubov (HFB), Approximation BCS (HFBCS), Champ Moyen Relativiste (RMF), Approximations Hartree (RH), Hartree-Fock (RHF) et Hartree-Bogoliubov (RHB) Relativistes, ... ; (ii) de présenter la procédure générale et les ingrédients qui entrent dans la construction d'une interaction effective, élément de base de ces théories dont l'intérêt majeur est de livrer des résultats comparables à l'expérience sans paramètre ajustable ; (iii) de discuter des effets des différentes approximations ou interactions effectives sur des résultats expérimentaux pris dans diverses zones de noyaux. Ces discussions seront surtout centrées sur les masses et les rayons des noyaux mais aussi sur certaines quantités plus significatives que l'on peut en extraire : énergies de séparation de deux neutrons

  2. Small Column Ion Exchange Design and Safety Strategy

    SciTech Connect

    Huff, T.; Rios-Armstrong, M.; Edwards, R.; Herman, D.

    2011-02-07

    Small Column Ion Exchange (SCIX) is a transformational technology originally developed by the Department of Energy (DOE) Environmental Management (EM-30) office and is now being deployed at the Savannah River Site (SRS) to significantly increase overall salt processing capacity and accelerate the Liquid Waste System life-cycle. The process combines strontium and actinide removal using Monosodium Titanate (MST), Rotary Microfiltration, and cesium removal using Crystalline Silicotitanate (CST, specifically UOP IONSIV{reg_sign}IE-911 ion exchanger) to create a low level waste stream to be disposed in grout and a high level waste stream to be vitrified. The process also includes preparation of the streams for disposal, e.g., grinding of the loaded CST material. These waste processing components are technically mature and flowsheet integration studies are being performed including glass formulations studies, application specific thermal modeling, and mixing studies. The deployment program includes design and fabrication of the Rotary Microfilter (RMF) assembly, ion-exchange columns (IXCs), and grinder module, utilizing an integrated system safety design approach. The design concept is to install the process inside an existing waste tank, Tank 41H. The process consists of a feed pump with a set of four RMFs, two IXCs, a media grinder, three Submersible Mixer Pumps (SMPs), and all supporting infrastructure including media receipt and preparation facilities. The design addresses MST mixing to achieve the required strontium and actinide removal and to prevent future retrieval problems. CST achieves very high cesium loadings (up to 1,100 curies per gallon (Ci/gal) bed volume). The design addresses the hazards associated with this material including heat management (in column and in-tank), as detailed in the thermal modeling. The CST must be size reduced for compatibility with downstream processes. The design addresses material transport into and out of the grinder and

  3. EVALUATION OF SUPPLEMENTAL PRE-TREATMENT DEVELOPMENT REQUIREMENTS TO MEET TRL 6 ROTARY MICROFILTRATION

    SciTech Connect

    HUBER HJ

    2011-10-03

    In spring 2011, the Technology Maturation Plan (TMP) for the Supplemental Treatment Project (RPP-PLAN-49827, Rev. 0), Technology Maturation Plan for the Treatment Project (T4S01) was developed. This plan contains all identified actions required to reach technical maturity for a field-deployable waste feed pretreatment system. The supplemental pretreatment system has a filtration and a Cs-removal component. Subsequent to issuance of the TMP, rotary microfiltration (RMF) has been identified as the prime filtration technology for this application. The prime Cs-removal technology is small column ion exchange (ScIX) using spherical resorcinol formaldehyde (sRF) as the exchange resin. During fiscal year 2011 (FY2011) some of the tasks identified in the TMP have been completed. As of September 2011, the conceptual design package has been submitted to DOE as part of the critical decision (CD-1) process. This document describes the remaining tasks identified in the TMP to reach technical maturity and evaluates the validity of the proposed tests to fill the gaps as previously identified in the TMP. The potential vulnerabilities are presented and the completed list of criteria for the DOE guide DOE G 413.3-4 different technology readiness levels are added in an attachment. This evaluation has been conducted from a technology development perspective - all programmatic and manufacturing aspects were excluded from this exercise. Compliance with the DOE G 413.3-4 programmatic and manufacturing requirements will be addressed directly by the Treatment Project during the course of engineering design. The results of this evaluation show that completion of the proposed development tasks in the TMP are sufficient to reach TRL 6 from a technological point of view. The tasks involve actual waste tests using the current baseline configuration (2nd generation disks, 40 psi differential pressure, 30 C feed temperature) and three different simulants - the PEP, an AP-Farm and an S

  4. Multidimensionally constrained relativistic mean-field study of triple-humped barriers in actinides

    NASA Astrophysics Data System (ADS)

    Zhao, Jie; Lu, Bing-Nan; Vretenar, Dario; Zhao, En-Guang; Zhou, Shan-Gui

    2015-01-01

    Background: Potential energy surfaces (PES's) of actinide nuclei are characterized by a two-humped barrier structure. At large deformations beyond the second barrier, the occurrence of a third barrier was predicted by macroscopic-microscopic model calculations in the 1970s, but contradictory results were later reported by a number of studies that used different methods. Purpose: Triple-humped barriers in actinide nuclei are investigated in the framework of covariant density functional theory (CDFT). Methods: Calculations are performed using the multidimensionally constrained relativistic mean field (MDC-RMF) model, with the nonlinear point-coupling functional PC-PK1 and the density-dependent meson exchange functional DD-ME2 in the particle-hole channel. Pairing correlations are treated in the BCS approximation with a separable pairing force of finite range. Results: Two-dimensional PES's of 226,228,230,232Th and 232,235,236,238U are mapped and the third minima on these surfaces are located. Then one-dimensional potential energy curves along the fission path are analyzed in detail and the energies of the second barrier, the third minimum, and the third barrier are determined. The functional DD-ME2 predicts the occurrence of a third barrier in all Th nuclei and 238U . The third minima in 230 ,232Th are very shallow, whereas those in 226 ,228Th and 238U are quite prominent. With the functional PC-PK1 a third barrier is found only in 226 ,228 ,230Th . Single-nucleon levels around the Fermi surface are analyzed in 226Th, and it is found that the formation of the third minimum is mainly due to the Z =90 proton energy gap at β20≈1.5 and β30≈0.7 . Conclusions: The possible occurrence of a third barrier on the PES's of actinide nuclei depends on the effective interaction used in multidimensional CDFT calculations. More pronounced minima are predicted by the DD-ME2 functional, as compared to the functional PC-PK1. The depth of the third well in Th isotopes decreases

  5. Active faulting Vs other surface displacing complex geomorphic phenomena. Case studies from a tectonically active area, Abruzzi Region, central Apennines, Italy

    NASA Astrophysics Data System (ADS)

    Lo Sardo, Lorenzo; Gori, Stefano; Falcucci, Emanuela; Saroli, Michele; Moro, Marco; Galadini, Fabrizio; Lancia, Michele; Fubelli, Giandomenico; Pezzo, Giuseppe

    2016-04-01

    could be possible to infer the genesis of the scarps as due to complex tectono-karstic phenomena. As for case (ii), our ongoing analyses are aimed to analyze the tectonic "significance" of some closed depressions, up to 4 km long and to 0,5-1 km large, that occur along the south-western slope of the Gran Sasso Range. All these small depression are NW-SE trending. As already described by Bosi et al. (1989), Galadini and Giuliani (1993), D'Agostino et al. (1998), Falcucci et al. (2015), these closed depressions are bounded by scarps carved onto the carbonate bedrock and, subordinately, onto early Quaternary slope deposits, reaching height of up to 5 m. These scarps are preferentially NE dipping, even if in few cases some SW dipping scarp are also present . The field work has permitted to attest that these scarps are related to shear planes that that displaced two subsequent of Early Pleistocene breccias formations (the Valle Valiano Fm. and Fonte Vedice Fm.; Bosi e Bertini, 1993; D'agostino et al., 1997). A paleoseismological trench was also performed across one of these scarps, attesting the activity of these shear planes also in recent times, providing indications result about the deformation style. Reference Bertini, T., & Bosi, C. (1993). La tettonica quaternaria della conca di Fossa (L'Aquila). Il Quaternario, 6(2), 293-314. Bertini, T., Bosi, C., & Galadini, F. (1989). La conca di Fossa-S. Demetrio dei Vestini. CNR, Centro di Studio per la Geologia Tecnica, ENEA, PAS in Elementi di tettonica pliocenicoquaternaria ed indizi di sismicita olocenica nell'Appennino laziale-abruzzese, Societa Geologica Italiana, L'Aquila, 26-58. Bosi, C., & Bertini, T. (1970). Geologia della media valle dell'Aterno. Memorie Società Geologica Italiana, 9(4), 719-777. D'Agostino, N., F. Speranza, & R. Funiciello., (1997) "Le Brecce Mortadella dell'Appennino Centrale: primi risultati di stratigrafia magnetica." Il Quaternario10.2: 385-388. D'Agostino, N., Chamot-Rooke, N., Funiciello, R

  6. Active faulting Vs other surface displacing complex geomorphic phenomena. Case studies from a tectonically active area, Abruzzi Region, central Apennines, Italy

    NASA Astrophysics Data System (ADS)

    Lo Sardo, Lorenzo; Gori, Stefano; Falcucci, Emanuela; Saroli, Michele; Moro, Marco; Galadini, Fabrizio; Lancia, Michele; Fubelli, Giandomenico; Pezzo, Giuseppe

    2016-04-01

    could be possible to infer the genesis of the scarps as due to complex tectono-karstic phenomena. As for case (ii), our ongoing analyses are aimed to analyze the tectonic "significance" of some closed depressions, up to 4 km long and to 0,5-1 km large, that occur along the south-western slope of the Gran Sasso Range. All these small depression are NW-SE trending. As already described by Bosi et al. (1989), Galadini and Giuliani (1993), D'Agostino et al. (1998), Falcucci et al. (2015), these closed depressions are bounded by scarps carved onto the carbonate bedrock and, subordinately, onto early Quaternary slope deposits, reaching height of up to 5 m. These scarps are preferentially NE dipping, even if in few cases some SW dipping scarp are also present . The field work has permitted to attest that these scarps are related to shear planes that that displaced two subsequent of Early Pleistocene breccias formations (the Valle Valiano Fm. and Fonte Vedice Fm.; Bosi e Bertini, 1993; D'agostino et al., 1997). A paleoseismological trench was also performed across one of these scarps, attesting the activity of these shear planes also in recent times, providing indications result about the deformation style. Reference Bertini, T., & Bosi, C. (1993). La tettonica quaternaria della conca di Fossa (L'Aquila). Il Quaternario, 6(2), 293-314. Bertini, T., Bosi, C., & Galadini, F. (1989). La conca di Fossa-S. Demetrio dei Vestini. CNR, Centro di Studio per la Geologia Tecnica, ENEA, PAS in Elementi di tettonica pliocenicoquaternaria ed indizi di sismicita olocenica nell'Appennino laziale-abruzzese, Societa Geologica Italiana, L'Aquila, 26-58. Bosi, C., & Bertini, T. (1970). Geologia della media valle dell'Aterno. Memorie Società Geologica Italiana, 9(4), 719-777. D'Agostino, N., F. Speranza, & R. Funiciello., (1997) "Le Brecce Mortadella dell'Appennino Centrale: primi risultati di stratigrafia magnetica." Il Quaternario10.2: 385-388. D'Agostino, N., Chamot-Rooke, N., Funiciello, R

  7. Estudio teórico de la desorción de Na y K de SiO2 estimulada por la acción de fotones o electrones

    NASA Astrophysics Data System (ADS)

    Domínguez Ariza, D.; López, N.; Illas, F.; Pacchioni, G.; Madey, T. E.

    Se ha estudiado el mecanismo de generación de sodio y potasio atómico a partir de muestras de SiO2 utilizando cálculos basados tanto en la teoría del funcional de la densidad como en métodos post-Hartree Fock, así como en el método de cluster para modelar el sólido. Como consecuencia del estudio se han propuesto distintos caminos posibles para la desorción, estimulada por la acción de fotones o electrones, de sodio y potasio desde el óxido de silicio, proporcionando por lo tanto una explicación a la atmósfera tenue de sodio y potasio de La Luna.

  8. Functional Phylogeny: the Use of the Sensitivity of Ribosomes to Protein Synthesis Inhibitors as a Tool to Study the Evolution of Organisms

    NASA Astrophysics Data System (ADS)

    Briones, Carlos; Koroutchev, Kostadin; Amils, Ricardo

    1998-10-01

    In order to study the functional phylogeny of organisms, forty different protein synthesis inhibitors with diverse domain and funcional specificities have been used to analyze forty archaeal, bacterial and eukaryotic translational systems. The inhibition curves generated with the different ribosome-antibiotic pairs have shown very interesting similarities among organisms belonging to the same phylogenetic group, confirming the feasibility of using such information in the development of evolutionary studies. A new method to extract most of the information contained in the inhibition curves is presented. Using a statistical treatment based on the principal components analysis of the data, we have defined coordinates for the organisms which have allowed us to perform a functional clustering of them. The phenograms obtained are very similar to those generated by 16/18S rRNA sequence comparison. These results prove the phylogenetic value of our functional analysis and suggest an interesting intersection between genotypic and phenotypic (functional) information.

  9. Designing and Supporting Cooperative and Ubiquitous Learning Systems for People with Special Needs

    NASA Astrophysics Data System (ADS)

    Fernández López, Álvaro; Rodríguez Fórtiz, María José; Noguera García, Manuel

    Cooperative work in schools helps students to learn behaviour norms, tolerate their partners and educators, and make decisions or accept the decisions from other people. In case of students with cognitive disabilities, cooperative work contributes to the socialization of the students by improving the communication and the integration in the classroom. New technologies foster guided and cooperative learning through didactic exercises and educational activities that adapt the educative context to user's needs and abilities. For this objective, the design must take into account non-funcional requirements for provide a future adaptation. This paper presents the design of one of such systems and the main decisions made in order to improve usability, adaptation, flexibility, and accessibility in ubiquitous spaces of it. The general architecture of the system and the platform that supports the development process of its software for educational activities are described in a real case study.

  10. Mejoras en el apuntado del telescopio de 2,15 mts de CASLEO

    NASA Astrophysics Data System (ADS)

    Aballay, J. L.; Casagrande, A. R.; Pereyra, P. F.; Marún, A. H.

    Con el objeto de optimizar el funcionamiento del telescopio de 2,15 mts. de CASLEO, se están eliminando los motores de calar, de guía y mecánica asociada. Para ésto, se están diseñando dos electrónicas que gobernarán, solamente, el motor de slew y el de tracking. Con el control del motor de slew se realizarán las funciones de slew y calar, controlando desde una PC la placa que maneja las rampas de velocidad. De este modo, el movimiento será programado y por lo tanto, más suave y preciso. Con el control del motor de tracking, a través de un generador de frecuencias programable desde una PC, se proveerá los movimientos necesarios para el tracking y guía.

  11. Analisis del contenido curricular de los Documentos Normativos del Programa de Ciencias en el area de biologia para la escuela superior del sistema de educacion publica de Puerto Rico: 1993-2012

    NASA Astrophysics Data System (ADS)

    Davila Montanez, Melissa

    Esta investigacion de naturaleza cualitativa se ocupo de realizar un analisis de contenido documental de los Documentos Normativos del Programa de Ciencias en el area de biologia de la escuela superior del sistema de educacion publica de Puerto Rico del periodo 1993-2012. Los documentos analizados fueron: Guia Curricular, 1995; Marco Curricular, 2003; Estandares de Excelencia, 1996, 2000 y Estandares de Contenido y Expectativas de Grado, 2007. Se indago si hubo cambios en significados en los Componentes Estructurales: Naturaleza de la ciencia, Paradigmas para la ensenanza de la ciencia, Funcion del curriculo formal, Mision de la ensenanza de la ciencia; Contenidos, destrezas y competencias, Estrategias de ensenanza y Evaluacion/Assessment del aprendizaje. El analisis sugiere que no hubo cambios sustanciales en los significados de los Componentes Estructurales. Los documentos estudiados muestran mayormente caracteristicas similares, aunque los documentos mas recientes eran mas descriptivos, explicativos y especificos.

  12. Fotometría UBVI en NGC 6231

    NASA Astrophysics Data System (ADS)

    Baume, G. L.; Vázquez, R. A.; Feinstein, A.

    Se ha realizado fotometría CCD UBVI en la zona del cúmulo abierto NGC 6231, habiéndose observado 1062 estrellas hasta una magnitud V≈ 19. Esto posibilita tener una imagen clara de la parte inferior de la secuencia principal del cúmulo. Combinando nuestros datos con tipos espectrales tomados de la literatura pudimos re-derivar la ley de absorción en dirección a este cúmulo y encontrar que los valores de R muestran variaciones de estrella a estrella. La secuencia principal inferior muestra también algunos rasgos intrigantes: hay un codo notorio en V≈ 13.5 seguido por un gran ``spread'' de magnitudes a color constante entre las estrellas débiles y una inusualmente alta densidad de estrellas a lo largo de una banda que se extiende 1.5 mag encima de la ZAMS. Los cálculos indican que el número esperado de estrellas de campo en dirección al cúmulo debería ser menor que el observado. Una re-evaluación de las funciones de luminosidad y masa dentro de los límites -7.5 < MV < 1.5 mag y 2 Msolar < M arroja pendientes planas para ambas funciones, lo que parece ser típico de cúmulos muy jóvenes. Todos estos rasgos son congruentes con un escenario joven donde las estrellas en fase de contracción están arribando a la secuencia principal.

  13. "Estudio tribologico de aceros para moldes. Aplicacion al moldeo por inyeccion de polibutilentereftalato reforzado con fibra de vidrio"

    NASA Astrophysics Data System (ADS)

    Martinez Mateo, Isidoro Jose

    fabricacion del molde, tienen una gran influencia sobre su comportamiento en servicio a lo largo de la vida util del molde. En la primera parte del presente estudio, a partir de ensayos punzon sobre disco, se ha determinado la relacion entre la resistencia al desgaste y la dureza de aceros para moldes obtenidos a partir de bloques de gran espesor, estudiando los principales mecanismos de desgaste que tienen lugar. A continuacion, con el fin de determinar el dano superficial que sufren los aceros para moldes en condiciones reales de inyeccion, se han estudiado distintos tipos de aceros utilizados comercialmente en moldes de inyeccion de polimeros y materiales compuestos, seleccionando las condiciones de operacion para determinar la variacion de la rugosidad superficial del acero en funcion del material inyectado, del numero de operaciones sucesivas de inyeccion y de la orientacion del flujo de inyeccion, mediante tecnicas de perfilometria optica y microscopia electronica de barrido. Ademas del dano superficial sufrido por el acero con el numero de piezas inyectadas, tambien se ha determinado la evolucion de la rugosidad superficial de los materiales inyectados, polibutilentereftalato (PBT) puro y materiales compuestos derivados de PBT por adicion de un 20 o un 50% en peso de fibra de vidrio. En el caso de las piezas inyectadas, se ha caracterizado su microestructura en funcion del flujo de inyeccion y de la densidad de fibra, se han determinado sus propiedades termicas y dinamico-mecanicas, asi como la variacion de la rugosidad superficial de las piezas inyectadas con el numero de operaciones de inyeccion y con la geometria de las distintas secciones de las piezas. Finalmente, se ha evaluado la resistencia a la abrasion de PBT reforzado con un 50% de fibra, en funcion del numero de piezas inyectadas y de la direccion de rayado con respecto a la orientacion del flujo de inyeccion.

  14. 2-D Hartee-Fock-Bogoliubov Calculations For Exotic Deformed Nuclei

    NASA Astrophysics Data System (ADS)

    Blazkiewicz, Artur; Oberacker, Volker E.; Umar, Sait A.; Teran, Edgar

    2003-10-01

    We solve the Hartree-Fock-Bogoliubov (HFB) equations in coordinate space; the computational method has been specifically designed to study ground state properties of nuclei near the neutron and proton drip lines teref1. The unique feature of our code is that it takes into account the strong coupling to high-energy continuum states, up to an equivalent single-particle energy of 60 MeV or higher. We solve the HFB equations for deformed, axially symmetric even-even nuclei in coordinate space on a 2-D lattice with Basis-Spline methods. For the p-h channel, the Skyrme (SLy4) effective N-N interaction is utilized, and for the p-p and h-h channel we use a delta interaction. Results teref2,ref3 are presented for binding energies, deformations, normal densities and pairing densities, Fermi levels, and pairing gaps. In particular, we calculate the properties of two light isotope chains up to the two-neutron dripline: oxygen (^22-28O) and sulfur (^40-52S). For some of the sulfur isotopes we found the "shape coexistence" what was also confirmed by RMF calculations of P. Ring and G.A. Lalazissis teref4. Furthermore, we study the strongly deformed heavy systems zirconium (^102,104Zr), cerium (^152Ce), and samarium (^158Sm).We are also planning to study other isotopes by running our new parallel MPI version of HFB code. Comparison with relativistic mean field theory and with experimental data is given whenever available. This work has been supported by the U.S. Department of Energy under grant No. DE-FG02-96ER40963 with Vanderbilt University. The numerical calculations were carried out on the IBM-RS/6000 SP supercomputer at NERSC in Berkeley and on our local "Beowulf" Vampire computer at Vanderbilt University. 99 ref1 Axially Symmetric Hartee-Fock-Bogoliubov calculations for nuclei near the drip lines,E. Teran, V.E. Oberacker and A.S. Umar, Phys. Rev. C 67, (June 2003) ref2 Half lives of isomeric states from SF of ^252Cf and large deformations in ^104Zr and ^158Sm, J.K. Hwang, A

  15. EVALUATION OF AP-FARM SIMULANT COMPOSITION FOR ROTARY MICROFILTER TESTING

    SciTech Connect

    HUBER HJ

    2011-09-19

    This document identifies the feed composition of a Hanford AP tank farm simulant for rotary microfiltration testing. The composition is based on an Hanford Tank Waste Operations Simulator (HTWOS) model run in combination with Tank Waste Information Network (TWINS) data and mineralogical studies of actual waste solids. The feed simulant is intended to be used in test runs at SRNL. The simulant will be prepared in two parts: (1) A supernate, composed of water-soluble salts and (2) The undissolved (actually, undissolvable) solids. Test slurries with distinct solids concentrations (e.g., 0.5, 5 and 10 wt%) are then prepared as needed. The base for the composition of supernate and solids is the modeled feed sequence for a deployment scenario of the Supplemental Pretreatment units within AP-farm. These units comprise a filtration part, the RMF, and a Cesium-removal part, a Small Column Ion Exchange. The primary use of this simulant is for filtration testing - however, in case that it is also used for ion-exchange tests, the amount of Cs-137 that would need to be added is available in Table 1 and Attachment 3. A modified model run (MMR-049) of the Hanford Tank Waste Operations Simulator (HTWOS) system plan 6 case 3 was performed to identify the feed sequence. Case 3 assumed supplemental treatment besides the low activity waste (LAW) melter with supplemental pretreatment supporting the pretreatment facility. The MMR did not cap the duration of supplemental pretreatment to 15 months, but rather used it throughout the entire treatment mission as an add-on option to the pretreatment facility at the Waste Treatment and Immobilization Plant (WTP). Tank 241-AP-105 (AP-105) was chosen as the feed tank to the filtration unit. Other parameters included a fixed minimum of 0.5 wt% solids in the feed and a maximum Na-concentration of 5M in the supernate. The solids rejection from the filtration unit was set to 99.99% and the maximum allowed amount of solids within tank AP-105 was set

  16. [In Process Citation].

    PubMed

    Petter da Silva, Fhaira; Beatriz Dallepiane, Loiva; Ramos Kirsten, Vanessa; Maria Kirchner, Rosane

    2016-01-01

    Introducción: la esperanza de vida está aumentando y convirtiéndose en un fenómeno característico de los países desarrollados y, cada vez más, de los países en desarrollo, como Brasil. El proceso de envejecimiento produce cambios en algunas funciones fisiológicas, como la pérdida del olfato o gusto o pérdida de apetito, entre otros, que terminan alterando la ingesta de alimentos de estos individuos.Objetivos: este estudio tuvo como objetivo evaluar el consumo de alimentos de los ancianos y de los ancianos más longevos en una ciudad del sur de Brasil.Métodos: un estudio transversal realizado mediante visitas a domicilio en Palmeira das Missões - RS, Brasil. Los datos sociodemográficos, antropométricos y dietéticos fueron recogidos a través de cuestionarios y recordatorio de 24 horas. La adecuación de nutrientes se evaluó de acuerdo con las ingestas de referencia en la dieta. Los datos fueron analizados utilizando el software SPSS 18.0.Resultados: el estudio incluyó a 424 adultos mayores, el 84.4% (n = 358) de ellos menores de 80 años y el 15.6% (n = 66) con más de 80 años. La ingesta de energía y proteínas fue insuficiente tanto para jóvenes adultos como para los más ancianos. El consumo de vitaminas y minerales ha sido insuficiente en todos los adultos mayores a excepción del hierro, que presentaba una ingesta excesiva. Hubo una diferencia estadísticamente significativa entre las personas de edad y mayores sólo en cuanto al consumo de lípidos y vitamina B12. Conclusión: la mayoría de los estudios con personas mayores corrobora los resultados obtenidos en este artículo. Una ingesta inadecuada de nutrientes puede dar lugar a deficiencias nutricionales y, por lo tanto, a cambios fisiológicos y patológicos que pondrían en peligro la capacidad funcional de los ancianos. El consumo de energía y de macronutrientes resultó insuficiente tanto para los ancianos como para los ancianos más longevos. Además, el consumo de vitaminas y

  17. Las ideologias, las ciencias naturales y sus implicaciones en la educacion cientifica

    NASA Astrophysics Data System (ADS)

    Lozada Roldan, Sandra

    Este estudio ausculto las concepciones epistemologicas de los docentes de ciencia del nivel secundario con relacion a las ideologias y las ciencias naturales. Tambien examino las posiciones de los docentes ante asuntos publicos relacionados a la ciencia. Para propositos de este estudio se diseno y se valido el cuestionario con el cual se obtuvieron los resultados. La investigacion es de tipo cuantitativa y se utilizo como diseno la encuesta. El cuestionario se administro en varias actividades de desarrollo profesional para maestros de ciencia. Un total de 78 maestros del nivel secundario respondieron el cuestionario. Para analizar los datos obtenidos se utilizaron estadisticas descriptivas como la distribucion de frecuencia y el porciento. Ademas se establecieron codigos y categorias para describir las posiciones de los maestros ante asuntos publicos relacionados a la ciencia. Los analisis demostraron que entre los docentes participantes de este estudio prevalecen ciertas concepciones epistemologicas adecuadas acerca de las ciencias naturales, a la luz de la literatura consultada. Entre estas concepciones se destacan las siguientes: a) la filosofia materialista de las ciencias naturales, b) la naturaleza tentativa y constructivista del conocimiento cientifico, c) el uso de una metodologia que garantiza cierto grado de objetividad y con el que se justifican y validan los enunciados cientificos y d) la funcion instrumental del conocimiento cientifico. Sin embargo, entre los docentes participantes de este estudio prevalecen ciertas concepciones epistemologicas erroneas acerca de las ciencias naturales, a la luz de la literatura consultada. Entre estas concepciones se destacan las siguientes: a) tendencia inductivista en el que las teorias cientificas comienzan con observaciones que establecen generalizaciones, b) secuencia jerarquica de la metodologia cientifica. Ademas, entre los docentes participantes de este estudio prevalecen concepciones epistemologicas adecuadas

  18. Evidence for dose-additive effects of a type II pyrethroid mixture. In vitro assessment.

    PubMed

    Romero, A; Ares, I; Ramos, E; Castellano, V; Martínez, M; Martínez-Larrañaga, M R; Anadón, A; Martínez, M A

    2015-04-01

    Despite the widespread use of pyrethroid insecticides that led to common exposure in the population, few studies have been conducted to quantitatively assess dose-additive effects of pyrethroids using a funcional measure involved in the common toxic mode of action. The aim of this study was to evaluate the potency and efficacy of 6 Type II pyretroids (α-cypermethrin, cyfluthrin, λ-cyhalothrin, deltamethrin, cyphenothrin and esfenvalerate) to evoke induction of both nitric oxide and lipid peroxides levels measured as malondialdehyde in three in vitro models (SH-SY5Y, HepG2 and Caco-2 human cells) as well as to test the hypothesis of dose additivity for mixtures of these same 6 pyrethroids. Concentration-responses for 6 pyrethroids were determined as well as the response to mixtures of all 6 pyrethroids. Additivity was tested assuming a dose-additive model. The human neuroblastoma SH-SY5Y cell line was the most sensitive in vitro model. The rank order of potency for cell SH-SY5Y viability MTT assay was deltamethrin>cyphenothrin>λ-cyhalothrin>cyfluthrin>esfenvalerate>α-cypermethrin. When 6 pyrethroids were present in the mixture at an equitoxic mixing ratio, the action on nitric oxide (NO) and lipid peroxides measured as malondialdehyde (MDA) production was consistent with a dose-additive model. The results of the present study are consistent with previous reports of additivity of pyrethroids in vivo e in vitro. PMID:25688004

  19. Research Progress on the Role of ABC Transporters in the Drug Resistance Mechanism of Intractable Epilepsy

    PubMed Central

    Xiong, Jie; Mao, Ding-an; Liu, Li-qun

    2015-01-01

    The pathogenesis of intractable epilepsy is not fully clear. In recent years, both animal and clinical trials have shown that the expression of ATP-binding cassette (ABC) transporters is increased in patients with intractable epilepsy; additionally, epileptic seizures can lead to an increase in the number of sites that express ABC transporters. These findings suggest that ABC transporters play an important role in the drug resistance mechanism of epilepsy. ABC transporters can perform the funcions of a drug efflux pump, which can reduce the effective drug concentration at epilepsy lesions by reducing the permeability of the blood brain barrier to antiepileptic drugs, thus causing resistance to antiepileptic drugs. Given the important role of ABC transporters in refractory epilepsy drug resistance, antiepileptic drugs that are not substrates of ABC transporters were used to obtain ABC transporter inhibitors with strong specificity, high safety, and few side effects, making them suitable for long-term use; therefore, these drugs can be used for future clinical treatment of intractable epilepsy. PMID:26491660

  20. [Not Available].

    PubMed

    Ortega, Rosa M

    2016-01-01

    El artículo de San Mauro y cols. profundiza en un tema de interés prioritario como es el estudio de los hábitos de ingesta de fluidos en personas de cuatro países: España, Portugal, México y Uruguay, para analizar si se cumplen (y si se conocen) las pautas de hidratación marcadas como adecuadas por organismos oficiales y, en concreto, por la EFSA. Es indudable la importancia de una correcta hidratación pues mientras que se puede vivir meses, o años, con una alimentación incorrecta, la deshidratación puede llevar a la muerte en un escaso periodo de tiempo. Por otra parte, un aporte ligeramente insuficiente de fluidos perjudica la salud, capacidad funcional y calidad de vida del individuo, por lo que debe ser evitada. Incluso algunos estudios encuentran hábitos y estilo de vida menos saludables en individuos con menor consumo de fluidos y pautas de hidratación más incorrectas. PMID:27571645

  1. Neurobiología de la impulsividad y los trastornos de la conducta alimentaria*

    PubMed Central

    Orozco-Cabal, Luis Felipe; Herin, David

    2009-01-01

    Resumen Introducción La impulsividad es un rasgo de personalidad multidimensional relacionado con el control del comportamiento y las emociones. Está presente de manera diversa en los trastornos de la conducta alimentaria, particularmente, en la bulimia nerviosa (BN). Aunque la relación entre la impulsividad y BN ha sido objeto de numerosas investigaciones, en la actualidad se desconocen los sustratos neurobiológicos de esta relación. Objetivos Discutir críticamente la evidencia que sugiere que las alteraciones en los sistemas neuronales relacio-nados con las funciones ejecutivas, con la formación de preferencias y con la regulación de los estados emocionales sirven como base para el rasgo de personalidad impulsiva, así como su estado en subgrupos de pacientes con BN. Métodos Búsqueda selectiva de la literatura relevante. Resultados y conclusiones Esta discusión ilustra la complejidad de la relación entre la impulsividad y BN, donde la impulsividad actúa como un factor de vulnerabilidad que puede sensibilizar al sujeto con BN a estados emocionales negativos, durante los cuales modifica el impacto de estímulos internos y externos sobre el comportamiento y su regulación, favoreciendo así patrones de comportamiento maladaptativos e inflexibles. PMID:19838321

  2. Bases para la elaboracion de unidades didacticas de calidad en el area de ciencias (Fisica y Quimica 3 deg ESO)

    NASA Astrophysics Data System (ADS)

    Maccioni, Elena Lucia

    Este Trabajo Fin de Master tiene como objeto, el estudio previo de la educacion de la ciencia en la actualidad y mas destacable, del diseno de las unidades didacticas segun las metodologias mas frecuentes aplicadas por los diferentes sistemas educativos en el area de las Ciencias teniendo en cuenta la importancia y el efecto de la psicologia del alumnado y todo ello como no puede ser de otro modo bajo el corse de la Legislacion aplicable, Estatal, Autonomica y europea. Con estos antecedentes, se extrae cuales son las preguntas que deben contestarse en la elaboracion de una unidad didactica de calidad en el contexto, generacional (edad y sexo), del Proyecto Educativo de Centro, y de la Programacion del Departamento, discutiendo y justificando cada uno de los apartados en que estructuradamente dividiremos dicha Unidad, con un formato manejable, util, y dinamico en el tiempo que sea un verdadero instrumento educativo de aula. Teniendo en cuenta estas premisas, se procede a hacer una recopilacion de una misma unidad didactica publicada por diferentes editoriales, elegidas no al azar, sino en funcion de su penetracion editorial en nuestros centros de ESO, siendo las elegidas (SM y Oxford). Las diferentes unidades seleccionadas son analizadas de forma critica, atendiendo a los criterios generales de calidad bajo parametros cientificos y normativos, concluyendo con la aportacion final que es la redaccion de unas pautas cientifico-pedagogicas, para redactar unidades didacticas de calidad en el area de la Ciencias, en concreto en la Asignatura de Fisica y Quimica de 3º de ESO.

  3. Telecommunications, computers and other complementary communication means on behalf of the disabled.

    PubMed

    Puig de la Bellacasa, R

    1980-01-01

    It took the author eleven months (1-3-1979 to 31-1-1980) to carry out the first part of a study and coordinate a number of working sessions in which he examined the state of the arts and put forward a program for the application of telecommunications, computers and other complementary communication means to the welfare of the disabled. The five areas of study are described in the present article: blindness, deaf-blindness and visual impairment; disability in the family; home-boundness due to disability, chronic illness or advanced age; speech impairments due to non-auditory causes; mental illness and related disorders. The study was carried out as a part of the activities of the "Foundation for the Development of the Social Function of Communications" (Fundacion para el Desarrollo de la Funcion Social de las Comunicaciones) and tries to open up a new perspective in Spain on technological applications for the handicapped. The main feature of the study is the proposal of Rehabilitation Engineering and Technical Aids Centre for the Disabled which starting from the telecommunications area, intends to make available to the handicapped the possibilities offered by technology. PMID:6161092

  4. Distribución espacial de órbitas con diferentes grados de caoticidad en modelos autoconsistentes de satélites galácticos

    NASA Astrophysics Data System (ADS)

    Muzzio, J. C.; Mosquera, M.

    En trabajos anteriores (Carpintero et al., Cel. Mech. Dynam. Astron. 85, 247, 2003), mostramos que las órbitas caóticas son muy importantes en los satélites galácticos. Sin embargo, los únicos modelos autoconsistentes de los que se disponía para ellos eran los de Heggie-Ramamani, cuya función de distribución depende sólo de la energía por lo que no mostraban diferencias entre las distribuciones de sus órbitas regulares y caóticas. Ahora, mediante una aproximación cuadrupolar, hemos logrado construir modelos autoconsistentes de satélites galácticos con distribuciones de velocidades anisotrópicas (lo que indica que sus funciones de distribución no dependen sólo de la energía) y hemos logrado revelar las diferencias entre las estructuras espaciales de las órbitas de distinta caoticidad.

  5. Investigating the influence of the interface in thiol-functionalized silver-gold nanoshells over lipase activity.

    PubMed

    Kisukuri, Camila M; Macedo, Alexandra; Oliveira, Caio C S; Camargo, Pedro H C; Andrade, Leandro H

    2013-12-23

    We employed thiol-funcionalized AgAu nanoshells (AgAu NSs) as supports for the covalent attachment of lipases (BCL, Burkholderia cepacia lipase; PPL, pancreatic porcine lipase). Specifically, we were interested in investigating the effect of the nature/size of the spacer in AgAu NSs-functionalized organic thiols over the covalent attachment of lipases. The catalytic performance of AgAu-lipase systems was measured in the kinetic resolution of (R,S)-1-(phenyl)ethanol via a transesterification reaction. In comparison to free BCL, the lipase attached to AgAu NSs using a small spacer such as cysteamine or mercaptoacetic acid, with the largest spacer mercaptoundecanoic acid, had the fastest conversion rate. The recycling potential for BCL was investigated. After three reaction cycles, the enzyme activity was kept at around 90% of the initial value. The results described herein show that the size of the spacer plays an important role in optimizing lipase activities in metallic nanoshells as solid supports. PMID:24313296

  6. Characterization and bioactivity study of nanohydroxyapatite on superhydrophilic vertically aligned carbon nanotubes using optical techniques

    NASA Astrophysics Data System (ADS)

    Ferreira Irineu, Joao Anderson; Marsi, Teresa C.; Santos, Tiago G.; Santo, Ana Maria E.; Rangel, Joao L.; Mengui, Ursula A.; Martin, Airton A.; Corat, Evaldo J.; Marciano, Fernanda R.; Lobo, Anderson O.

    2012-03-01

    Vertically-aligned multi-walled carbon nanotubes (VACNT) is of particular interest in regenerative medicine. Templateinduced hydroxyapatite (HA) has broad prospects in applied fields of bone regenerative medicine. Thus, it becomes very attractive a combination these two excellent materials to bone tissue engineering applications. In this study the HA/VACNT nanocomposites were used as scaffolds to Human osteoblast cells culture. Superhydrophilic VACNT films were obtained by CVD method and funcionalized by oxygen plasma. The fabrication of HA/VACNT nanocomposites was performed with a direct electrodeposition of the thin HA films on the VACNT films. The bioactivity and biomineralization in vitro process of superhydrophilic HA/VACNT nanocomposites were investigated using simulated body fluid (SBF) and optical techniques. The characterization of of HA/VACNT nanocomposites was performed before and after soaking 21 days in SBF and compared to superydrophilic VACNT films. Fourier transform infrared spectroscopy, micro X-ray fluorescence spectrometer by energy-dispersive and X-ray difractogram were employed to investigate the structural and chemical properties. The morphology was investigated by FEG-SEM analysis. After 21 days was identified that others biological apatites were formed only on HA/VACNT nanocomposites. Optical techniques showing a powerful tool to characterizated and investigated the bioactivity in vitro process. These findings were very atractive to application of this new nanocomposite to bone tissue regeneration.

  7. Ependimoma myxopapilar sacro gigante con osteolisis

    PubMed Central

    Ajler, Pablo; Landriel, Federico; Goldschmidt, Ezequiel; Campero, Álvaro; Yampolsky, Claudio

    2014-01-01

    Objetivo: la presentación de un caso de una paciente con un ependimoma sacro con extensa infiltración y destrucción ósea local. Descripción del caso: una mujer de 53 años acudió a la consulta por dolor lumbosacro y alteraciones sensitivas perineales y esfinterianas. La imágenes por Resonancia Magnética (IRM) y la Tomografía Axial Computada (TAC) mostraron una lesión expansiva gigante a nivel S2-S4 con extensa osteólisis e invasión de tejidos adyacentes. Se realizó una exéresis tumoral completa con mejoría del estatus funcional. La anatomía patológica informó ependimoma mixopapilar. Discusión: la extensión de la resección quirúrgica es el mejor predictor de buen pronóstico. El tratamiento radiante se reserva como opción adyuvante para las resecciones incompletas y recidiva tumoral. La quimioterapia sólo debería utilizarse en casos en que la cirugía y la radioterapia estén contraindicadas. Conclusión: Los ependimomas mixopapilares sacros con destrucción ósea y presentación intra y extradural son muy infrecuentes y deben ser tenidos en cuenta entre los diagnósticos diferenciales preoperatorios. Su resección total, siempre que sea posible, es la mejor alternativa terapéutica. PMID:25165615

  8. Teorí­as de primer y segundo orden sobre el potencial de ciertas figuras de equilibrio de cuerpos celestes

    NASA Astrophysics Data System (ADS)

    Gumbau, Manuel Forner

    2010-11-01

    Uno de los problemas que aborda la Mecánica Celeste es la determinación de las figuras de equilibrio de los cuerpos celestes. Para investigar su solución mediante métodos directos, se precisa evaluar el potencial generado por su autogravitación, el generado por su fuerza centrí­fuga y el generado por la fuerza de atracción entre los cuerpos. Los métodos clásicos de Finlay y Kopal que afrontan estos problemas, para determinar el potencial autogravitatorio en las configuraciones de equilibrio, emplean desarrollos en serie de los potenciales interior y exterior del potencial autogravitatorio. Estos métodos incurren en el error de suponer la convergencia en capas donde resulta cuestionable dicha convergencia para estos desarrollos en serie. En este trabajo se han elaborado unos algoritmos que contemplan toda la casuí&stica y que permiten una manipulación efic iente del producto de polinomios de Legendre, del producto de funciones asociada s de Legendre y del producto de armónicos esféricos como combinacióon lineal de ellos mismos, respectivamente. Se han obtenido, para primer y segundo orden en las amplitudes, los desarrollos correctos para los potencial es interior y exterior del potencial autogravitatorio para configuraciones de equilibrio aisladas, y , en primer orden de amplitudes, los mismos potenciales para los sistemas binarios próximos. Se ha elaborado un método analítico, en primer orden respecto de las amplitudes, para la determinación del potencial de marea en sistemas binarios próximos en el cual se manifiesta la forma de la componente secundaria del sistema

  9. Systems biology analysis of the proteomic alterations induced by MPP+, a Parkinson's disease-related mitochondrial toxin

    PubMed Central

    Monti, Chiara; Bondi, Heather; Urbani, Andrea; Fasano, Mauro; Alberio, Tiziana

    2015-01-01

    Parkinson's disease (PD) is a complex neurodegenerative disease whose etiology has not been completely characterized. Many cellular processes have been proposed to play a role in the neuronal damage and loss: defects in the proteosomal activity, altered protein processing, increased reactive oxygen species burden. Among them, the involvement of a decreased activity and an altered disposal of mitochondria is becoming more and more evident. The mitochondrial toxin 1-methyl-4-phenylpyridinium (MPP+), an inhibitor of complex I, has been widely used to reproduce biochemical alterations linked to PD in vitro and its precursor, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP), to induce a Parkinson-like syndrome in vivo. Therefore, we performed a meta-analysis of the literature of all the proteomic investigations of neuronal alterations due to MPP+ treatment and compared it with our results obtained with a mitochondrial proteomic analysis of SH-SY5Y cells treated with MPP+. By using open-source bioinformatics tools, we identified the biochemical pathways and the molecular functions mostly affected by MPP+, i.e., ATP production, the mitochondrial unfolded stress response, apoptosis, autophagy, and, most importantly, the synapse funcionality. Eventually, we generated protein networks, based on physical or functional interactions, to highlight the relationships among the molecular actors involved. In particular, we identified the mitochondrial protein HSP60 as the central hub in the protein-protein interaction network. As a whole, this analysis clarified the cellular responses to MPP+, the specific mitochondrial proteome alterations induced and how this toxic model can recapitulate some pathogenetic events of PD. PMID:25698928

  10. Neurobiología del autismo y TDAH mediante técnicas de neuroimagen: divergencias y convergencias

    PubMed Central

    Proal, Erika; Olvera, Jorge González; Blancas, Aurea S.; Chalita, Pablo J.; Castellanos, F. Xavier

    2013-01-01

    En el área clínica algunos síntomas del trastorno por déficit de atención e hiperactividad (TDAH), se presentan en los pacientes con trastorno del espectro autista (TEA). Se ha demostrado que existen alteraciones en circuitos cerebrales que impactan en fallas cognitivas y de comportamiento específicas de cada uno de estos trastornos. Sin embargo, han sido poco estudiados los correlatos cerebrales que hay detrás tanto de las similitudes como de las diferencias sintomatológicas. En la presente revisión se analizaron los estudios meta-analíticos existentes estructurales y funcionales en TDAH y TEA. Por un lado, se observaron convergencias en circuitos como el dorsal atencional, de funciones ejecutivas, visual, somatomotor y circuito de activación por defecto. Estas similitudes posiblemente explican las manifestaciones comórbidas entre los trastornos como la falla en la integración de información, motricidad fina y procesos atencionales específicos. Por otro lado, específicamente en el TDAH se observan déficits en el circuito de recompensa y ventral atencional, sistemas involucrados en la medición de efectos de reforzamiento y monitoreo atencional. En TEA los circuitos más afectados fueron los implicados en procesos de cognición social y lenguaje. En conclusión, existen correlatos neuronales en TEA que explican las manifestaciones clínicas tanto convergentes como divergentes presentes en TDAH. PMID:23897144